
NAME

        O-Saft - OWASP SSL advanced forensic tool
                 OWASP SSL audit for testers


SYNOPSIS

        o-saft.pl [COMMANDS ..] [OPTIONS ..] target [target target ...]

        where  [COMMANDS]  and  [OPTIONS]  are described below  and target is
        a hostname either as full qualified domain name or an IP address.
        Multiple commands and targets may be combined.

        All  commands  and  options  can also be specified in a  rc-file, see
        RC-FILE  below.

        I.g. all commands start with a  '+'  character and options start with
        '-'  or  '--'  characters. Anything else is treated as target name.

        Arguments (commands, options and targets) can be used in any order.
        If options are given multiple times,  or when they configure the same
        behaviour (for example toggles like --tlsv2 and --no-tlsv2), the last
        given one wins.

        Arguments are read from following sources in that sequence:
          1. rc-file  if not disabled with --no-rc
             for details, please see section  RC-FILE  below
          2. environment variable OSAFT_OPTIONS
          3. command-line


DESCRIPTION

        This tool lists  information  about remote target's  SSL certificate,
        and tests the remote target according given list of ciphers.

        Note:  Throughout this description  `$0'  is used as an alias for the
        program name  'o-saft.pl'.


QUICKSTART

        Before going into  a detailed description  of the  purpose and usage,
        here are some examples of the most common use cases:

        * Show supported (enabled) ciphers of target:
          o-saft.pl +cipher --enabled example.tld

        * Show details of certificate and connection of target:
          o-saft.pl +info example.tld

        * Check certificate, ciphers and SSL connection of target:
          o-saft.pl +check example.tld

        * Check connection to target for vulnerabilities:
          o-saft.pl +vulns example.tld

        * Get the certificate's Common Name for a bunch of servers:
          o-saft.pl +cn example.tld some.tld other.tld

        * List more usage examples
          o-saft.pl --help=examples

        * List all available commands:
          o-saft.pl --help=commands

        * Get table of contents for complete help
          o-saft.pl --help=toc

        * Show just one section, for example SECURITY, from help
          o-saft.pl --help=SECURITY

        * Show all  --help=*  commands
          o-saft.pl --help=HELP

        * Search for text in O-Saft's help and show with context
          o-saft --help=your-text

        * Start the simple GUI
          o-saft.tcl 

        * Start the simple GUI which uses o-saft.pl in a Docker image
          o-saft.tcl --docker

        For more specialised test cases, refer to the sections  COMMANDS  and
        OPTIONS  below. For more examples please refer to  EXAMPLES  section.

        For more details, please see  Requirements  and  INSTALLATION  below.


WHY?

        Why a new tool for checking SSL security and configuration when there
        are already a dozen or more such good tools in existence (in 2012)?

        Unique features:
          * working in closed environments, i.e. without internet connection
          * checking availability of ciphers independent of installed library
          * checking for all possible ciphers (up to 65535 per SSL protocol)
          * mainly same results on all platforms.

        Currently available tools suffer from some or all of following issues:
          * lack of tests of unusual SSL certificate configurations
          * may return different results for the same checks on given target
          * missing tests for modern SSL/TLS functionality
          * missing tests for specific, known SSL/TLS vulnerabilities
          * no support for newer, advanced, features e.g. CRL, OCSP, EV
          * limited capability to create your own customised tests

        Other  reasons or problems  are that other tools are either binary or
        use additional binaries and hence are not portable to other platforms.

        In contrast to (all?) most other tools, including "openssl(1)", it can
        be used to "ask simple questions" like "does target support STS" just
        by calling:
          o-saft.pl +hsts_sts example.tld

        For more, please see  EXAMPLES  section below.
        If it should run on systems with old software (perl or Perl modules),
        please see  DEBUG  section below.


SECURITY

        This tool is designed to be used by people doing security or forensic
        analyses. Hence no malicious input is expected.

        There are no special security checks implemented. Some parameters are
        roughly sanitised according unwanted characters.  In particular there
        are no checks according any kind of code injection.

        Care should be taken, when additional tools and modules are installed
        as described in  INSTALLATION  below. In particular it is recommended
        to do these installations into directoies  specially prepared for use
        with  o-saft.pl .
        No other tools of your system  should use  these additional installed
        tools, for example by accident or because environment variables point
        to them.

        Note that compilation and installation of  additional tools (openssl,
        Net::SSLeay, etc.) uses known insecure configurations and features!
        This is essential to make  o-saft.pl  able to check for such insecurities.

        It is  highly recommended to do these installations and use the tools
        on a separate testing system.

        DO NOT USE THESE INSTALLATIONS ON PRODUCTIVE SYSTEMS.


CONCEPTS

        The purpose of  O-Saft  is to do the work,  not to force the user  to
        learn a new tool or to install "newer" software first.
        However, the user "should do something" if necessary depending on the
        reported results.

        Developers may read more details on the concept in  doc/concepts.txt.

    This help text

        The sequence of the sections in the help text doesn't strictly follow
        the common guidlines for UNIX-style man pages.  This is because it is
        important to understand the concepts of the tool and what options and
        commands are in context of the tool. In particular the  DESCRIPTION  
        section contains only a very brief description. The  OPTIONS  section
        follows the  COMMANDS  section.

    Results

        Results of checks are marked  'yes'  or 'no'.  This leaves the proper
        interpretation, if the result is "good" or "bad", to the user.
        Background:  it is not always possible to rate a result as  "good" or
        "bad" or "insecure" or whatever. That's why  O-Saft  can not give the
        "the best" or "proper" recommendation.  In practice it depends on the
        context what a recommendation or countermeasure should be. That's why
        results are marked  'yes'  or  'no'  if considered "questionable", or
        "not good" (for example according other checks).

        For more details please see  RESULTS  below.


TECHNICAL INFORMATION

        It is important to understand, which provided information is based on
        data returned by underlaying (used) libraries and the information
        computed directly.

    Version 23.11.23 and later

        Starting with version 23.11.23 all checks for ciphers are done by our
        own plain Perl code, just the SSL/TLS-related checks and informations
        use "Net::SSLeay(3pm)" and openssl.
        Since version 23.12.23 OpenSSL 3.0.x is supported also.

        Beside  new and removed funtionality  in OpenSSL (details see below),
        OpenSSL also changed some texts in its responses. Again this makes it
        hard to parse openssl's output properly. Therfore checking for cipher
        is now done without openssl.  Using openssl for checking ciphers must
        be requested explicitly with the  --ciphermode=openssl  option.

        Keep in mind that it is not possible  to check if the target supports
        ancient ciphers with openssl 3.x. There even does not exist a patched
        version, as we used before, to do it. However, any openssl 1.x can be
        be used if specified with the  --openssl=  option.

        Following changes in OpenSSL have been observed (incomplete list):
           # our command/option| OpenSSL 1.x           | OpenSSL 3.0.x
           #-------------------+-----------------------+---------------------
            -ssl2 -no_ssl2     | -ssl2 -no_ssl2        | <<not supported>>
            -ssl3 -no_ssl3     | -ssl3 -no_ssl3        | <<not supported>>
            -tls1_3 -no_tls1_3 | <<not supported>>     | -tls1_3 -no_tls1_3
            -dtls1  -dtls1_2   | <<not supported>>     | -dtls1  -dtls1_2
                               | <<not supported>>     | -legacy_renegotiation
                               | <<not supported>>     | -prioritize_chacha
            +selfsigned        | self signed           | num=18:self-signed
            +sslversion        | TLSv1.2               | TLSv12
            +renegotiation     | renegotiation info" (id=65281), len=1
                               |         Secure Renegotiation IS NOT supported
            +sigkey_len        | 2048                  | 2104
            +sigkey_value      | hexhex                | Signature Value hexhex
            +dh_parameter      | ECDH, P-256, 256 bits | X25519, 253 bits
            +cipher-selected   | New, TLSv1/SSLv3, ... | New, TLSv1.3, ...
           #-------------------+-----------------------+---------------------

        As the purpose of this tool is to check for any cipher,  wether known
        or not, using modern OpenSSL 3.x is not feasible because it is simply
        not possible. This restriction may apply to other tools which rely on
        openssl or the underlying libssl too.

        Beyond this limitation, checking old protocols and ciphers on targets
        which use modern libraries, may result in a bunch of warnings.  If it
        happens, following can be done to get a better overview:

          o-saft.pl target --header +cipher
          o-saft.pl target --header +cipher --nossl2 --nossl3 --notls1
          o-saft.pl target --header +cipher --no-warnings
          o-saft.pl target --header +cipher --nossl2 --nossl3 --notls1 --no-warnings
          o-saft.pl target --header +cipher --ciphermode=openssl --openssl=/path/openssl

    Version 19.11.19 and later

        Starting with version 19.11.19 the  +cipher  command does not use any
        external library. Checking for ciphers is done using plain Perl code.
        Only other collected SSL/TLS related information requires an external
        library, in general libssl.
        The description about OpenSSL and libssl below applies only if any of
        the options  --ciphermode=openssl  or  --ciphermode=ssleay  are given
        with the  +cipher  command.

        Therefore following commands and options changed:
           # VERSION < 19.11.19       |  change ...
           #--------------------------+---------------------------------
            * +cipher                 | uses internal method
            * +cipherall              | command obsolete, !!Hint is printed
            * +cipherraw              | command obsolete, !!Hint is printed
            * --force-openssl         | 
            * --openssl-ciphers       | changed to  --ciphermode=openssl
            * --openssl=TOOL          | TOOL only used for  +cipher  --ciphermode=openssl
            * --legacy=owasp          | option obsolete
           #--------------------------+---------------------------------

        The historic commands  +cipherall  and  +cipherraw should be replaced
        with the new syntax, as follows:

           # VERSION < 19.11.19       |  VERSION > 19.11.19
           #--------------------------+---------------------------------
            * +cipher                 |  +cipher  --ciphermode=ssleay
            * +cipher --force-openssl |  +cipher  --ciphermode=openssl
            * +cipherall              |  +cipher
            * +cipherraw              |  +cipher  --ciphermode=intern
           #--------------------------+---------------------------------

    Version before 19.11.19

        Up to version 19.11.19 the default behaviour for the  +cipher command
        was to use libssl. The commands  +cipherall  and  +cipherraw  did not
        use any other library as described below.

    OpenSSL, libssl, libcrypto

        In general the tool uses Perl's "Net::SSLeay(3pm)" module which itself
        is based on libssl and/or libssleay library of the operating system.
        It's possible to use other versions of these libraries, see options:
          * --exe-path=PATH  --exe=PATH
          * --lib-path=PATH  --lib=PATH
          * --envlibvar=NAME

        The external "openssl(1)"  is called to extract  some information from
        its output. The version of  openssl  can be controlled with following
        options:
          * --openssl=TOOL
          * --no-openssl
          * --openssl-ciphers   --force-openssl
          * --exe-path=PATH     --exe=PATH
          * --openssl-cnf=PATH
          * --openssl-s_client  --s_client

        OpenSSL is recommended to be used for libssl and libcrypto.  Versions
        0.9.8k to 1.0.2e (Jan. 2016) are known to work. However, versions be-
        for 1.0.0 may not provide all information.
        Some functionality (checks) of  O-Saft  may be missing or fail,  when
        openssl versions 1.1.x are used (because functionality was removed).
        LibreSSL  is not recommended, because  some functionality  considered
        insecure, has been removed.
        For more details, please see  INSTALLATION  below.


    Certificates and CA

        All checks according the validity of the certificate chain  are based
        on the root CAs installed on the system.  Note that "Net::SSLeay(3pm)"
        and "openssl(1)"  may have their own rules where to find the root CAs.
        Please refer to the documentation on your system for these tools.
        However, there are folloing options to tweak these rules:
          * --ca-file=FILE
          * --ca-path=DIR
          * --ca-depth=INT

    Commands and options

        All arguments  starting with  '+'  are considered  COMMANDS  for this
        tool. All arguments starting with  '--'  are considered  OPTIONS  for
        this tool.

        Reading any data from STDIN or here-documents is not yet supported.
        It's reserved for future use.

    Environment variables

        Please see  ENVIRONMENT  .

    Requirements

        For  +info  and  +check  (and all related) commands,  perl (5.x) with
        following modules (minimal version) is recommended:

          * IO               1.25 (2011)
          * IO::Socket::INET 1.37 (2011)
          * IO::Socket::SSL  1.90 (2013)
          * Net::DNS         0.66 (2011)
          * Net::SSLeay      1.49 (2012)

        However, it is recommended to use the most recent version of the mod-
        ules which then gives more accurate results and less warnings. If the
        modules are missing, they can be installed for example with:

              cpan Net::SSLeay

        Note: if you want to use advanced features of openssl or Net::SSLeay,
        please see  INSTALLATION section how to compile and install the tools
        fully customised. Requirements for  OpenSSL  are described there.

        Also an openssl executable should be available, but is not mandatory.

        For checking DH parameters of ciphers, openssl 1.0.2  or newer should
        be available. If an older version of openssl is found, we try hard to
        extract the  DH parameters  from the data returned by the server, see
        +cipher-dh  command.

        If you need to run on systems with older perl or Perl module versions
        please refer to the  DEBUG  section for more information.

    External tools

        For building and/or viewing the documentation, any of following tools
        should be available:

          * aha              0.5-1
          * perldoc          v3.2801
          * pod2man
          * pod2usage
          * podviewer        v0.18
          * tkpod
          * tput
          * stty


COMMANDS

        There are commands for various tests according the  SSL connection to
        the target, the targets certificate and the used ciphers.

        All commands are prepended by a  '+'  character to easily distinguish
        from other arguments and options. However, some --OPTIONS options are
        treated as commands for historical reason or compatibility with other
        programs.

        The most important commands are (in alphabetical order):
          +check +cipher +info +http +list +quick +sni +sni_check +version

        A list of all available commands will be printed with:
          o-saft.pl --help=cmds

        The description of all other commands will be printed with:
          o-saft.pl --header --help=commands

        The summary and internal commands return requested information or the
        results of checks. These are described below.

        Note that some commands may be a combination of other commands, see:
          o-saft.pl --header --help=intern

        The following sub-sections only describe the commands,  which do more
        than giving a simple information from the target.  All other commands
        can be listed with:
          o-saft.pl --header --help=commands

        The final sub-sections  Notes about commands  describes some notes
        about special commands and related commands.


    Commands for information about this tool

        All these commands will exit after execution (cannot be used together
        with other commands).

      +ciphers

          Show known ciphers in format like "openssl ciphers".
          It also accepts the  -v  and  -V  option (like openssl).
          Use  +list  command for more information according ciphers.

      +list

          Show all ciphers supported by this tool. This includes cryptogrphic
          details of the cipher and some internal details.

          Different output formats are used for the  --legacy=*  option:
            * --legacy=simple   - simple space-separated output
            * --legacy=full     - TAB-separated output with more data
            * --legacy=owasp    - simple output sorted according OWASP scoring
            * --legacy=openssl  - output same as with  +ciphers  command
            * --legacy=ssltest  - output like "ssltest --list"


      +VERSION

          Just show version and exit.

      +version

          Show version information for both the program and the  Perl modules
          that it uses, then exit.

          Use  --v  option to show more details.

      +libversion

          Show version of openssl.

      +quit

          Show internal data and exit, used for testing and debugging only.
          Please see  TESTING  below.

    Commands to check SSL details

        Following (summary and internal) commands are simply a shortcut for a
        list of other commands. For details of the list use:
              o-saft.pl --help=intern

      +check

          Check the SSL connection for security issues. Implies  +cipher .

      +host

          Print details about the targets hostname, DNS, etc.
          These details are usually printed only for the  +check  and  +info
          command, but not for any individual command.

      +http

          Perform HTTP checks (like STS, redirects etc.).

      +info

          Overview of most important details of the SSL connection.

          Use  --v  option to show details also, which span multiple lines.

      +quick

          Quick overview of checks. Implies  --enabled  and  --label=short.

      +pfs

          Check if servers offers ciphers with prefect forward secrecy (PFS).

      +protocols

          Check for protocols supported by target.

      +vulns

          Check for various vulnerabilities.

      +sts
      +hsts

          Various checks according STS HTTP header.
          This option implies  --http,  means that  --no-http is ignored.

      +sni

          Check for Server Name Indication (SNI) usage.

      +sni_check
      +check_sni

          Check for Server Name Indication (SNI) usage  and  validity  of all
          names (CN, subjectAltName, FQDN, etc.).

      +bsi

          Various checks according BSI TR-02102-2 and TR-03116-4 compliance.

      +ev

          Various checks according certificate's extended Validation (EV).

          Hint: use option  --v  --v  to get information about failed checks.

      +sizes

          Check length, size and count of some values in the certificate.

      +s_client

          Dump data retrieved from  "openssl s_client ..."  call. This should
          be used for debugging only.
          It can be used just like openssl itself, for example:
              openssl s_client -connect host:443 -no_sslv2

      +dump

          Dumps internal data for SSL connection and target certificate. This
          is mainly for debugging and  should not be used together with other
          commands (except  +cipher).
          Each key-value pair is enclosed in  '#{'  and  '#}' .

          Using  --trace  --trace  dumps data of  lib/SSLinfo  too.

      +exec

          Command used internally when requested to use other libraries.
          This command should not be used directly.


    Commands to test ciphers provided by target

          Beside the description of the commands itself here, please see also
          Notes about commands  below.

      +cipher

          Check target for ciphers,  either all ciphers, or ciphers specified
          with  --cipher=CIPHER  option.

          Use  --v  option to see all ciphers being checked.

      +cipher-default

          Lists the cipher selected by the server for each protocol sometimes
          referred to as "default cipher".

          For each protocol the two selected ciphers are shown,  one returned
          by the server if the cipher list in the  ClientHello is sorted with
          the strongest cipher first, and one returned  if the cipher list in
          the ClientHello is sorted with strongest cipher last.
          See  Notes about commands  for details.

      +cipher-dh

          Checked target for ciphers. All ciphers supported by the server are
          printed with their DH or ECDH paramaters (if available).
          ciphers.

      +null
      +cipher-null

          Check if target accepts NULL ciphers.

      +adh
      +cipher-adh

          Check if target accepts ciphers with anonymous key exchange.

      +export
      +cipher-exp

          Check if target accepts EXPORT ciphers.

      +cbc
      +cipher-cbc

          Check if target accepts CBC ciphers.

      +des
      +cipher-des

          Check if target accepts DES ciphers.

      +cipher-rc4

          Check if target accepts RC4 ciphers.

      +edh
      +cipher-edh

          Check if target supports ephemeral ciphers.

      +cipher-pfs

          Check if target supports ciphers with PFS.

      +cipher-strong

          Check if target selects strongest cipher.

      +cipher-weak

          Check if target selects weak cipher (oposite of  +cipher-strong).

    Discrete commands to test SSL connection and certificate details

        Discrete commands, please see:
          o-saft.pl --help=commands

    Notes about commands

      +cipher vs. +cipher-dh

          While  +cipher  prints checked ciphers,  +cipher-dh  prints ciphers
          with their DH or ECDH paramaters (if available)  only for supported
          ciphers.

      +cipher vs. +cipher-default

          Both commands show the default cipher foreach protocol.

          +cipher  lists a summary of ciphers selected by the server for each
          protocol requested by the user (for example by using options like:
          --sslv3  --tlsv1 etc.). When the  --v  option is used, all selected
          ciphers for all known protocols are listed. This summary focuses on
          counts for various ciphers.

          +cipher-default  lists the  cipher selected  by the server for each
          protocol.

      +cipher-selected vs. +cipher-default

          +selected  lists the cipher selected by the server if no particular
          protocol was specified and the system's default cipher list is send
          in the ClientHello to the server.

          +cipher-default  lists the  cipher selected  by the server for each
          protocol.

      +cipher-strong vs. +cipher-default

          +strong-cipher  shows the result of the check if strong ciphers are
          preferred by the server. It is a check command.

          +cipher-default  lists the  cipher selected  by the server for each
          protocol. It is a information command.

          It is not possible to check if a server uses 'SSLHonorCipherOrder'.
          Even if it is used (switched on),  it is not possible to  check the
          specified order of the ciphers.

          I. g. it is expected that the order is according the cipher suite's
          strength, meaning the most strongest first, and the weakest last.
          It doesn't make sense to use an order where a weak cipher preceds a
          stronger one. Such a (mis-)configuration should be detected.

          Having this in mind, the algorithm to detect a  proper cipher order
          is as simply as follows:
            1. pass sorted cipher list with strongest cipher first
            2. pass sorted cipher list with strongest cipher last
          if the server returns the same cipher for both checks, it's assumed
          that it prefers to use the most strongest cipher. In this case it's
          obvious that 'SSLHonorCipherOrder' is set (exceptions see below).

          Exceptions:
          If either, the server or the client,  uses only one cipher suite in
          the list, SSLHonorCipherOrder cannot be detected at all.
          The same happens, if only one cipher in the client's list matches a
          cipher in the server's list.

      +tlsextdebug

      +tlsextensions

      +extensions vs. +tlsextensions

          "Certificate extensions" are shown with  +extensions  while the TLS
          protocol extensions are shown with  +tlsextensions.
          Use  +tlsextdebug  to show more information about the  TLS protocol
          extensions.

      +http2 +spdy +spdy3 +spdy31 +spdy4 +prots

          These commands are just an alias for the  +protocols  command.

      +wildcard

      +hostname vs. +wildhost vs. +altname vs. +rfc_2818

          The commands  +cn  and  +altname  print the  information stored  in
          the certificate.
          The command  +hostname  checks if the given hostname matches the CN
          value in the certificate.  Note that wildcard names in the CN, only
          allow to contain one '*'.
          The command  +wildcard  checks if the given hostname does not match
          any name specified in the certificate's "subjectAltname". This check
          is useful  if the certificate and the configuration  must comply to
          RFC 6125 or EV certificates.


OPTIONS

        All options are written in lowercase. Words written in all capital in
        the description here is text provided by the user.

    Options for help and documentation

      --h

          Brief documentation of  --help*  options/commands.

      --help

          Complete user documentation.

      --help*

      --help=cmds

          Show available commands; short form.

      --help=commands

          Show available commands with short description.

      --help=opt

          Show available options; short form.

      --help=options

          Show available options with their description.

      --help=checks

          Show available checks.

      --help=tools

          Description of tools around O-Saft, when, where and how to use.

      --help=cmd

          Show additional and user specified commands.

      --help=cfg-cmd

          Show additional and user specified commands.  Output can be used in
          rc-file or as option.

      --help=check-cfg
      --help=cfg-check

          Show texts used as labels in output for checks (see  +check)  ready
          for use in rc-file or as option.

      --help=data

          Show available information.

      --help=data-cfg
      --help=cfg-data
      --help=cfg-info

          Show texts used  as labels in output for  data  (see  +info)  ready
          for use in rc-file or as option.

      --help=hint

          Show texts used in hint messages.

      --help=hint-cfg
      --help=cfg-hint

          Show texts used in hint messages ready for use in the rc-file or as
          option.

      --help=text

          Show texts used in various messages.

      --help=text-cfg
      --help=cfg-text

          Show texts used in various messages ready for use in the rc-file or
          as option.

      --help=legacy

          Show possible legacy formats (used as value in  --legacy=TOOL).

      --help=compliance

          Show available compliance checks.

      --help=intern

          Show internal commands.

      --help=alias

          Show alias for commands and options.

      --help=pattern

          Show list of cipher pattern (used for  --cipher=CIPHER).

      --help=range

          Show list of cipherranges (see  --cipherrange=RANGE).

      --help=toc
      --help=content

          Show headlines from help text. Useful to get an overview.

      --help=SECTION

          Show  'SECTION'  from documentation, see  --help=toc  for a list.
          Example:
              o-saft.pl --help=EXAMPLES

      --help=ourstr

          Show regular expressions to match our own strings used in output.

      --help=regex

          Show regular expressions used internally.

      --help=gen-html

          Print documentation in HTML format.

      --help=gen-pod

          Print documentation in POD format.

      --help=gen-wiki

          Print documentation in mediawiki format.

      --help=gen-cgi

          Print HTML form to be used for CGI.

      --help=error
      --help=problem

          Show  KNOWN PROBLEMS  section with  description of known  error and
          warning messages.

      --help=faq

          Show  KNOWN PROBLEMS  and  LIMITATIONS  section.

      --help=glossary

          Show common abbreviation used in the world of security.

      --help=links

          Show list of URLs related to SSL/TLS.

      --help=rfc

          Show list of RFC related to SSL/TLS.

      --help=todo

          Show known problems and bugs.

      --help=exit

          Show possible  --exit=KEY  options. Used for debugging only.

      --help=warnings

          Show warning messages defined in code.

      --help=program.code

          For developers.

    Options for all commands (general)

      --dns

          Do DNS lookups to map given hostname to IP, do a reverse lookup.

      --no-dns

          Do not make DNS lookups.
          Note  that the corresponding IP and reverse hostname may be missing
          in some messages then.

      --host=HOST

          Specify HOST as target to be checked. Legacy option.

      --port=PORT

          Specify PORT of target to be used. Legacy option.

      --host=HOST --port=PORT HOST:PORT HOST

          When giving more than one HOST argument,  the sequence of the given
          HOST argument and the given  --port=PORT and the given  --host=HOST
          options are important.
          The rule how ports and hosts are mapped is as follows:

            * HOST:PORT arguments are used as is (connection to HOST on PORT)
            * only HOST is given, then previous specified PORT is used

          Note that URLs are treated as HOST:PORT, if they contain a port.
          Example:
              o-saft.pl +cmd host-1 --port 23 host-2 host-3:42 host-4

          will connect to:
            * host-1:443
            * host-2:23
            * host-3:42
            * host-4:23

      --proxyhost=PROXYHOST --proxy=PROXYHOST:PROXYPORT

          Make all connection to target using PROXYHOST.

          Also possible is: --proxy=PROXYUSER:PROXYPASS@PROXYHOST:PROXYPORT

      --proxyport=PROXYPORT

          Make all connection to target using PROXYHOST:PROXYPORT.

      --proxyuser=PROXYUSER

          Specify username for proxy authentication.

      --proxypass=PROXYPASS

          Specify password for proxy authentication.

      --starttls

          Use 'STARTTLS' command to start a TLS connection via SMTP.
          This option is a shortcut for  --starttls=SMTP .

      --starttls=SMTP
      --starttls=PROT

          Use 'STARTTLS' command to start a TLS connection via protocol.
          'PROT' may be any of:  'SMTP', 'IMAP', 'IMAP2', 'POP3', 'FTPS',
          'RDP', 'LDAP' or 'XMPP' .

          For  --starttls=SMTP  see  --dns-mx  also to use MX records instead
          of host

      --starttls-delay=SEC

          Number of seconds to wait before sending a packet, to slow down the
          'STARTTLS' requests. Default is 0.
          This may prevent blocking of requests by the target due to too much
          or too fast connections.
          Note:  In this case there is an automatic suspension and retry with
          a longer delay.

      --cgi
      --cgi-exec

          Internal use for CGI mode only.

    Options for SSL tool

      --rc

          Read rc-file if exists, from directory where program was found.

      --no-rc

          Do not read rc-file.

      --rc=FILE

          Use FILE instead of the default rc-file '.o-saft.pl'.

      --exitcode

          The exit status code will be greater 0, if any of following applies:
          * any check returns  'no', except if  'no (<<...>>)'
          * insecure protocols are available
          * insecure ciphers are supported
          * ciphers without PFS are supported, disable with  --exitcode-cipher

          In particular, the status code will be the total count of all these
          checks. The status code will also be printed at end, like:
              # EXIT 23

          Parts of these checks can be diasabled,  see  --exitcode-*  options
          below.

          Use  --v or --exitcode-v  to see details about the performed checks.

          Functionality implemented experimental, may change in future.

      --exitcode-v

          Print information about performed checks.

      --exitcode-quiet

          Do not print status code at end, like '# EXIT 23'.

      --exitcode-no-checks

          Do not count checks with result 'no' for  --exitcode .

      --exitcode-no-low  --exitcode-no-weak  --exitcode-no-medium

          Do not count LOW, WEAK or MEDIUM security ciphers for  --exitcode .

      --exitcode-no-ciphers

          Do not count any ciphers for  --exitcode .

      --exitcode-no-pfs

          Do not count ciphers without PFS for  --exitcode .

      --openssl-s_client --s_client

          Use  "openssl s_slient ..."  call to retrieve more information from
          the SSL connection.  This is disabled by default on Windows because
          of performance problems. Without this option (default on Windows !)
          following information are missing:
              compression, expansion, renegotiation, resumption,
              selfsigned, verify, chain, protocols, DH parameters

          See  lib/SSLinfo  for details.

          If used together with  --trace, s_client  data will also be printed
          in debug output of  lib/SSLinfo.

      --no-openssl

          Do not use external "openssl"  tool to retrieve information. Use of
          "openssl" is disabled by default on Windows.
          Note that this results in some missing information, see above.

      --openssl=TOOL

          'TOOL'        can be a path to openssl executable; default: openssl

      --openssl-cnf=FILE --openssl-conf=FILE

          'FILE'        path of directory or full path of openssl.cnf

          If set, environment variable OPENSSL_CONF will be set to given path
          (or file) when "openssl(1)" is started. Please see openssl's man page
          for details about specifying alternate  openssl.cnf  files.

      --openssl-ciphers --force-openssl

          Options are obsolete. Please use  --ciphermode=openssl  instead.

          Use openssl to check for supported ciphers; default: "IO::Socket(3pm)"

          This option forces to use  "openssl s_slient -connect CIPHER .." to
          check if a cipher is supported by the remote target. This is useful
          if the  --lib=PATH  option doesn't work (for example due to changes
          of the API or other incompatibilities).

      --exe-path=PATH
      --exe=PATH

          'PATH'        is a full path where to find openssl.

      --lib-path=PATH
      --lib=PATH

          'PATH'        is a full path where to find libssl.so, libcrypto.so.

          See  HACKER's INFO  below for a detailed description how it works.

      --envlibvar=NAME

          'NAME'  is the name of a environment variable containing additional
          paths for searching dynamic shared libraries.
          Default is LD_LIBRARY_PATH.

          Check your system for the proper name, for example:
              DYLD_LIBRARY_PATH, LIBPATH, RPATH, SHLIB_PATH.

      --inc=PATH

          'PATH'        is a full path where to find additional Perl modules

          This option is not avaliable as "--inc PATH".

      --no-inc=REGEX

          'REGEX'       all paths matching this RegEx are removed from @INC

          This option is not avaliable as "--no-inc REGEX".
          See  HACKER's INFO  below for a detailed description.

      --ssl-error

          The connection to  a target may fail, or even block, due to various
          reasons for example lost network at all, blocking at firewall, etc.
          In particular when checking ciphers with  +cipher , this may result
          in long delays until results are printed.
          Using this option stops trying to do more connections to the target
          when  --ssl-error-max=CNT  consecutive errors occoured, or when the
          total amount of errors increases  --ssl-error-total=CNT.

          Note that this may result in loss of information and/or checks.

      --ssl-error-max=CNT

          Max. amount of consecutive errors (default: 5).

      --ssl-error-timeout=SEC

          Timeout in seconds when a failed connection is treated as error and
          then counted (default: 1).

      --ssl-error-total=CNT

          Max. total amount of errors (default: 10).

      --ssl-lazy

          I.g. this tools tries to identify available functionality according
          SSL versions from the underlaying libraries.  Unsupported  versions
          are then disables and a warning is shown.
          Unfortunately some libraries have  not implemented all functions to
          check availability of a specific SSL version, which then results in
          a compile error.

          This option disables the strict check of availability.
          If the underlaying library doesn't support the required SSL version
          at all, following error may occour:
              Can't locate auto/Net/SSLeay/CTX_v2_new.al in @INC ...

          See Note on SSL versions  for a general note about SSL versions.
          A more detailled description of the problem and how Net::SSLeay be-
          haves, can be found in the source of  o-saft.pl ,
          see section starting at
              #| check for supported SSL versions

      --timeout=SEC

          Timeout in seconds when connecting to the target (default: 2).


      --call=METHOD

          'METHOD'      method to be used for specific functionality

          Available methods:
            * 'info-socket'    - use internal socket to retrieve information
            * 'info-openssl'   - use external openssl to retrieve information
            * 'info-user'      - use usr_getinfo() to retrieve information
            * 'cipher-socket'  - use internal socket to ckeck for ciphers
            * 'cipher-openssl' - use external openssl to ckeck for ciphers
            * 'cipher-user'    - use usr_getciphers() to ckeck for ciphers

          Method names starting with:
          * 'info-'
            are responsible to retrieve information  about the SSL connection
            and the target certificate (i.e. what the +info command provides)
          * 'cipher-'
            are responsible to connect to the target  and test if it supports
            the specified ciphers  (i.e. what the  +cipher  command provides)
          * 'check-'
            are responsible for performing the checks (i.e. what's shown with
            the  +check  command)
          * 'score-'
            are responsible to compute  the score based on check results

          The second part of the name denotes which kind of method to call:
            * 'socket'      - the internal functionality with sockets is used
            * 'openssl'     - the exteranl openssl executable is used
            * 'user'        - the external special function,  as specified in
                              user's  lib/OUsr.pm,  is used.

          Example:
              --call=cipher-openssl

          will use the external "openssl(1)" executable to check the target for
          supported ciphers.

          Default settings are:
              --call=info-socket --call=cipher-socket --call=check-socket

          Just for curiosity, instead of using:
              o-saft.pl --call=info-user --call=cipher-user --call=check-user --call=score-user ...

          consider to use your own script like:
              #!/usr/bin/env perl
              usr_getinfo();usr_getciphers();usr_checkciphers();usr_score();

          :-))

      -v

          Print list of ciphers in style like: "openssl ciphers -v".
          Option used with  +ciphers  command only.

      -V

          Print list of ciphers in style like: "openssl ciphers -V".
          Option used with  +ciphers  command only.

    Options for SSL connection to target

      --ciphermode=intern
      --ciphermode=openssl
      --ciphermode=ssleay
      --ciphermode=MODE

          Following 'MODE's are supported:
          * 'intern'    - scan for ciphers using internal method; (default)
          * 'openssl'   - scan for ciphers using external openssl executable
          * 'ssleay'    - scan for ciphers using  IO::Socket and  Net::SSLeay
          * 'dump'      - same as 'intern' but print  all cipher information,
                          useful when postprocessed by usr/* tools

      --socket-reuse

          TCP socket will be reused for  next connection attempt  even if SSL
          connection failed.

      --no-socket-reuse

          Close TCP socket and then reopen for next connection attempt if SSL
          connection failed.

          This is useful for some servers which may return an "TLS alert"  if
          the connection fails and then fail again on the same socket.

      --ignore-no-connect

          A simple check if the target can be connected  will be performed by
          default.  If this check fails, the target will be ignored, means no
          more requested checks will be done.  As this connection check some-
          times fails due to various reasons, the check can be disabled using
          this option.

      --no-md5-cipher

          Do not use *-MD5 ciphers for other protocols than SSLv2.
          This option is only effective with  +cipher  command.

          The purpose is to avoid warnings from "IO::Socket::SSL(3pm)"  like:
              Use of uninitialized value in subroutine entry at lib/IO/Socket/SSL.pm line 430.

          which occours with some versions of "IO::Socket::SSL(3pm)"  when a
          *-MD5  ciphers will be used with other protocols than SSLv2.

          Note that these ciphers will be checked for SSLv2 only.


      --sslv2
      --sslv3
      --tlsv1
      --tlsv11
      --tlsv12
      --tlsv13
      --dtlsv09
      --dtlsv1
      --dtlsv11
      --dtlsv12
      --dtlsv13
      --SSL, --protocol SSL

      --no-sslv2
      --no-sslv3
      --no-tlsv1
      --no-tlsv11
      --no-tlsv12
      --no-tlsv13
      --no-dtlsv09
      --no-dtlsv1
      --no-dtlsv11
      --no-dtlsv12
      --no-dtlsv13
      --no-SSL

          * 'SSL'       can be any of:
            ssl, ssl2, ssl3, sslv2, sslv3, tls1, tls1, tls11, tls1.1, tls1-1,
            tlsv1, tlsv11, tlsv1.1, tlsv1-1 (and similar variants for tlsv1.2
            and tlsv1.3), dtls1, dtls12, dtls13.
          For example:  --tls1  --tlsv1  --tlsv1_1  are all the same.

          (--SSL variants):    Test ciphers for this SSL/TLS version.
          (--no-SSL variants): Don't test ciphers for this SSL/TLS version.

      --no-tcp
      --no-tls

          Shortcut for:
          --no-sslv2 --no-sslv3 --no-tlsv1 --no-tlsv11 --no-tlsv12 --no-tlsv13

      --tcp
      --tls

          Shortcut for:  --sslv2 --sslv3 --tlsv1 --tlsv11 --tlsv12 --tlsv13

      --no-udp
      --no-dtls

          Shortcut for:
          --no-dtlsv09 --no-dtlsv1 --no-dtlsv11 --no-dtlsv12 --no-dtlsv13

      --udp
      --dtls

          Shortcut for:  --dtlsv09 --dtlsv1 --dtlsv11 --dtlsv12 --dtlsv13

      --nullsslv2

          This option  forces  to assume that  SSLv2  is enabled  even if the
          target does not accept any ciphers.

          The target server may accept connections with  SSLv2  but not allow
          any cipher. Some checks verify if  SSLv2  is enabled at all,  which
          then would result in a failed test.
          The default behaviour is to assume that  SSLv2 is not enabled if no
          ciphers are accepted.

      --http

          Make a HTTP request if cipher is supported.

          If used twice debugging will be enabled using  environment variable
          'HTTPS_DEBUG'.

      --no-http

          Do not make HTTP request.

      --http-user-agent=UA

          Use 'UA' for HTTP header "User-Agent:" in HTTP(s) requests.

      --sni

          Make SSL connection in SNI mode.

      --no-sni

          Do not make SSL connection in SNI mode (default: SNI mode).

      --sni-toggle
      --toggle-sni

          Test with and witout SNI mode.

      --force-sni

          Do not check if SNI seems to be supported by "Net::SSLeay(3pm)".
          Older versions of openssl and its libries do not support SNI or the
          SNI support is implemented buggy. By default it's checked if SNI is
          properly supported. With this option this check can be disabled.

          Be warned that this may result in improper results.

      --servername=NAME
      --sni-name=NAME

          If SNI mode is active, see  --sni  above, 'NAME' is used instead of
          hostname for connections to the target.  If SNI mode is not active,
          see  --no-sni  above, 'NAME' is not used. The default is undefined,
          which forces to use the given FQDN.

          This is useful, for example when an IP instead of a FQDN was given,
          where a correct hostname (i.g. a FQDN) needs to be specified.

          Note: i.g. there is no need to use this option,  as a correct value
          for the SNI name will be choosen automatically (except for IPs).
          However, it is kind of fuzzing ... even setting to an  empty string
          is possible.

          Limitation:  the same 'NAME' is used for all targets,  if more than
          one target was specified.

      --no-cert

          Do not get data from target's certificate, return empty string.

      --no-cert --no-cert

          Do not get data from  target's certificate,  return  default string
          of lib/SSLinfo (see  --no-cert-text=TEXT  option).

      --no-cert-text=TEXT

          Set 'TEXT' to be returned from  lib/SSLinfo  if no certificate data
          is collected due to use of  --no-cert.

      --ca-depth=INT

          Check certificate chain to depth 'INT' (like openssl's -verify).

      --ca-file=FILE

          Use 'FILE' with bundle of CAs to verify target's certificate chain.

      --ca-path=DIR

          Use 'DIR' where to find CA certificates in PEM format.

      --ca-force
      --force-ca

        NOT YET IMPLEMENTED
          I. g. openssl uses default settings where to find certificate files.
          When  --ca-file=FILE  and/or  --ca-path=DIR  was used,  this default
          will be overwritten by appropriate options passed to openssl. If the
          default does not work as expected,  --force-ca  can be used to force
          setting of proper values according well known common defaults. See:
              o-saft.pl +version
              o-saft.pl +version --force-ca

          to see the used settings.

      --alpn

          Use  -alpn  option for openssl.

      --no-alpn

          Do not use  -alpn  option for openssl.

      --no-npn
      --no-nextprotoneg

          Do not use  -nextprotoneg  option for openssl.

      --proto-alpn=NAME

          Name of protocol to be added to list of  applcation layer protocols
          (ALPN), which is used for any connection to the targets.
          See  --cipher-alpn=NAME  also.

      --proto-npn=NAME

          Name of protocol to be added to list of  next protocol negotiations
          (NPN), which is used for any connection to the targets.
          See  --cipher-npn=NAME  also.

      --ssl-compression --compression

          Use SSL option "compression" for connection.

      --no-ssl-compression --no-compression

          Use SSL option "no compression" for connection (default: don't use)

      --no-reconnect

          Do not use  -reconnect  option for openssl.

      --no-tlsextdebug

          Do not use  -tlsextdebug  option for openssl.

      --sclient-opt=VALUE

          Argument or option passed to openssl's  s_client  command.

    Options for  +cipher  command

      --connect-delay=SEC

          Additional delay in seconds  after each connect for a cipher check.
          This is useful when connecting to servers which have IPS in place,
          or are slow in accepting new connections or requests.

      --cipher=CIPHER

          Only check for 'CIPHER' instead of using ciphers from internal list
          (default). Multiple options can be specified.

          'CIPHER' can be any cipher suite name or (internal) hex key, see:

             o-saft.pl +list

          for known, valid keys and cipher names.

          'CIPHER' can also be any of the internal defined patterns, see:

             o-saft.pl --header --help=cipherpattern

          If 'CIPHER' does not match a hex key, i.e. '0x03000035', it is used
          as pattern (RegEx) to match cipher suite names. For example:
          'AES256-SHA' matches 28 cipher suites,  while 'AES256-SHA$' matches
          14 ciphers, see:
              lib/Ciphers.pm find-names=AES256-SHA
              lib/Ciphers.pm find-names=AES256-SHA$

          To be sure that exactly one cipher suite matches, use for example:
              --cipher=^AES256-SHA$
              --cipher=0x03000035

          Hex keys must be specified with a leading '0x'  followed by exactly
          8 uper case hex characters '[0-9A-F]'.

          The pattern can be common RegEx like 'GCM|CHACHA'.  Simple OpenSSL-
          style pattern are also accepted, for example: 'AES:ECDH'.

          When  --ciphermode=openssl or --ciphermode=ssleay is used, 'CIPHER'
          can only be any string or a hex key accepted by openssl. Examples:
            * --cipher=DHE_DSS_WITH_RC4_128_SHA
            * --cipher=0x03000066

          will be mapped to  'DHE-DSS-RC4-SHA'

          'CIPHER' can also be any pattern accepted by openssl, for example:
            * --cipher='!DES:!ADH:!aNULL'

          Default is 'ALL:NULL:eNULL:aNULL:LOW:EXP' as specified in lib/SSLinfo.

          See  LIMITATIONS  also.

      --cipher-alpn=NAME

          Name of protocol to be added to list of  applcation layer protocols
          (ALPN), which is used for cipher checks.

          * --cipher-alpn=,     - sets empty list.
          * --cipher-alpn=,,    - sets list to empty element "".

      --cipher-npn=NAME

          Name of protocol to be added to list of  next protocol negotiations
          (NPN), which is used for cipher checks.

          * --cipher-npn=,      - sets empty list.
          * --cipher-npn=,,     - sets list to empty element "".

          Note:  setting empty list or element most likely does not work with
          openssl executable (for example  --force-openssl).

      --cipher-curve=NAME

          Name of ecliptic curve to be added to list of ecliptic curves (EC),
          which is used for cipher checks.

          * --cipher-curve=,    - sets empty list.
          * --cipher-curve=,,   - sets list to empty element "".

          Note:  setting empty list or element most likely does not work with
          openssl executable (for example  --force-openssl).

      --range=RANGE
      --cipherrange=RANGE

          Specify range of cipher constants to be tested with  +cipher  .
          Following 'RANGE's are supported:
          * 'rfc'             - all ciphers defined in various RFCs; default
          * 'shifted'         - 'rfc' + some shifted by 64 bytes to the right
          * 'intern'          - 'rfc' + 'shifted'
          * 'long'            - like 'rfc' but more lazy list of constants
          * 'huge'            - all constants  0x03000000 .. 0x0300FFFF
          * 'safe'            - all constants  0x03000000 .. 0x032FFFFF
          * 'full'            - all constants  0x03000000 .. 0x03FFFFFF
          * 'SSLv2'           - all ciphers according RFC for SSLv2
          * 'SSLv2_long'      - more lazy list of constants for SSLv2
          * 'SSLv3'           - all ciphers according RFC for SSLv3
          * 'SSLv3_SSLv2'     - all ciphers for SSLv3 with SSLv2
          * 'TLSv12'          - all ciphers according RFC for TLSv12
          * 'TLSv13'          - all ciphers according RFC for TLSv13
          * 'GREASE'          - all GREASE ciphers according RFC
          * 'c0xx'            - ECC ciphers, constants 0x0300C000 .. 0x0300C0FF
          * 'ccxx'            - ECC ciphers, constants 0x0300CC00 .. 0x0300CCFF
          * 'ecc'             - all constants for ciphers using ECC

          Note: 'SSLv2' is the internal list used for testing SSLv2 ciphers.
          It does not make sense to use it for other protocols; however ...

          For the full list and details about the ranges, please see:

              o-saft.pl --header --help=range

          If any  --cipher=CIPHER  is used,  --cipherrange=RANGE  is ignored.
          See  LIMITATIONS  also.

      --slow-server-delay=SEC

          Additional delay in seconds  after the server is connected  using a
          proxy or before starting 'STARTTLS'.
          This is useful when connecting via  slow proxy chains or connecting
          to slow servers before sending the 'STARTTLS' sequence.

      --ssl-maxciphers=CNT

          Maximal number of ciphers sent in a sslhello (default: 32).

      --ssl-double-reneg

          Send SSL extension  'reneg_info'  even if list of ciphers includes
          'TLS_EMPTY_RENEGOTIATION_INFO_SCSV' (default: do not include)

      --ssl-nodata-nocipher

          Some servers do not answer  (i.g. they disconnect) if  none of  the
          offered ciphers is supported by the server.

          Continue testing with next ciphers  when the target  disconnects or
          does not send data within specified timeout (see  --timeout).
          Useful for TLS intolerant servers.

      --no-ssl-nodata-nocipher

          Abort testing with next ciphers when the target disconnects.

      --ssl-use-ecc

          Use supported elliptic curves.  Default on.

      --ssl-use-ec-point

          Use TLS 'ec_point_formats' extension.  Default on.

      --ssl-use-reneg

          Test for ciphers with "secure renegotiation" flag set.
          Default: don't set "secure renegotiation" flag.

      --ssl-retry=CNT

          Number of retries when connection timed-out (default: 2).

      --ssl-timeout=SEC

          Number of seconds to wait until connection is qualified as timeout.

      --dns-mx
      --mx

          Get DNS MX records for given target and check the returned targets.
          (only useful with  --starttls=SMTP).

    Options for checks and results

        Options used for  +check  command:

      --enabled

          Only print result for ciphers accepted by target.

      --disabled

          Only print result for ciphers not accepted by target.

      --https_body

          Prints HTTP response body of the target also, if requested with
          +https_body  , which is disabled by default (because it may be huge
          amount of data not related to SSL/TLS).

      --ignorecase

          Checks are done case-insensitive.

      --no-ignorecase

          Checks are done case-sensitive. Default: case-insensitive.
          Currently only checks according CN, alternate names in the target's
          certificate compared to the given hostname are effected.

      --ignore-no-reply

          When checking for the TLS "heartbeat" extension, the server may not
          respond at all, which would result in a  "no reply"  message.  This
          marks the check for  +heartbleed  as 'no'.
          I.g.  a server is  not vulnerable to the  heartbleed attack  if the
          TLS "heartbeat" extension is disabled. Hence the check result  'no'
          may be mis-leading.  This option  treats the  "no reply"  result as
          "not vulnerable" and returns  'yes'  then.

          Note: if the server does not respond for this check,  does not mean
          that the "heartbeat" extension is switched off.  If unsure, disable
          this lazy check with  --no-ignore-no-reply .

    Options for output format

      --label=TYPE

          Defines the format of the descriptive text (label) for  +check  and
          +info  command.

          Following 'TYPE's are supported:

      --label=long

          Prints full text for labels:

              Certificate Common Name:  some.tld

      --label=short

          Prints short less descriptive text for labels:

              Common Name:              some.tld

      --label=key

          Internal format: print name of key instead of text as label. Key is
          Prints name of key instead of text as label. The key is that of the
          internal data structure(s).

              [cn]                      some.tld

          For ciphers and protocols, the corresponding  hex value  is used as
          key. Note that these values are unique.

      --legacy=*

      --legacy=TOOL

          For compatibility with other tools,  the output format used for the
          result of the  +cipher  command can be adjusted to mimic the format
          of other SSL testing tools.

          The argument to the  --legacy=TOOL  option  is the name of the tool
          who's format of output is to be simulated.

          Following 'TOOL's are supported:
          * 'sslaudit'          - similar to  sslaudit
          * 'sslcipher'         - similar to  ssl-cipher-check
          * 'ssldiagnos'        - similar to  ssldiagnos
          * 'sslscan'           - similar to  sslscan
          * 'ssltest'           - similar to  ssltest
          * 'ssltestg'          - similar to  ssltest -g
          * 'ssltest-g'         - similar to  ssltest -g
          * 'sslyze'            - similar to  sslyze
          * 'ssl-cipher-check'  - same as sslcipher
          * 'ssl-cert-check'    - similar to  ssl-cert-check
          * 'testsslserver'     - similar to  TestSSLServer.jar
          * 'thcsslcHeck'       - similar to  THCSSLCheck

          Note that these legacy formats only apply to  output of the checked
          ciphers. Other texts like headers and footers are adapted slightly.

          When using ths option, please do not expect identical output as the
          'TOOL'. It is a best guess and should be parsable in a very similar
          way.

      --legacy=TYPE
      --legacy=compact

          Internal format: mainly avoid tabs and spaces format is as follows:
              Some Label:<-- anything right of colon is data

      --legacy=full

          Internal format: pretty print each label in its own line,  followed
          by data prepended by tab character (useful for  +info  only).

      --legacy=owasp

          Results for cipher checks use rating from OWASP Cipher Cheat Sheet.

      --legacy=quick

          Internal format: use tab as separator; ciphers are printed with bit
          length (implies  --tab).

      --legacy=simple

          Internal default format.

      --format=0x
      --format=\x
      --format=/x
      --format=hex
      --format=raw

          This option is used to specify the format of the result lines. This
          covers the value of the result line only.

          * 'raw'       - Print raw data as passed from  lib/SSLinfo.
            Note:  all data will be printed as is,  without  additional label
            or formatting. It's recommended to use the  option in conjunction
            with exactly one command.  Otherwise the user needs  to know  how
            to "read" the printed data.

          * 'hex'       - Convert some data to hex: 2 bytes separated by ':'.
          * '0x'        - Convert some data with hex values:
                          2 bytes prepended by '0x' and separated by a space.
          * '/x'        - Same as  --format=\x
          * '\x'        - Convert some data with hex values:
                          2 bytes prepended by '\x' and no separating char.

      --tty
      --format-tty

          Get the screen width and then adapt  output of documentation to fit
          to that width. If the environment variable 'COLUMNS' is not set the
          command 'tput' or 'stty' of system is used to get the screen width.

          It's a very simple approach to make texts better readable on narrow
          devices like tablets. For more details, please see:

              perdoc o-saft.pl   # the section Note:tty  there

      --format-width=NN

          Set the screen width to 'NN' characters (see  --format-tty  also).
          Default will be calculated automatically.

      --format-ident=NN

          Set the amount of spaces used for identation (see  --tty  also).
          Default is 2.

      --format-arrow=CHR

          Set the additional chacacter when lines are split. Default: ↲

      --header

          Print formatting header.  Default for  +check,  +info,  +quick  and
          and  +cipher  only.

      --no-header

          Do not print formatting header.
          Usefull if raw output should be passed to other programs.

          Note: must be used on command-line to inhibit all header lines.

      --ignore-cmd=CMD
      --ignore-output=CMD
      --no-cmd=CMD
      --no-output=CMD

          Do not print output (data or check result) for command 'CMD'. 'CMD'
          is any valid command, see  COMMANDS ,  without leading '+'.
          Option can be used multiple times.

          --ignore-out=,    sets empty list.

      --score

          Print scoring results. Default for  +check.

      --no-score

          Do not print scoring results.

      --separator=CHAR
      --sep=CHAR

          'CHAR'    will be used as separator between  label and value of the
                    printed results. Default is  ':'.

      --tab

          'TAB' character (0x09, \t)  will be used as separator between label
          and value of the printed results.
          As label and value are already separated by a  TAB  character, this
          options is only useful in conjunction with the  --legacy=compact
          option.

      --showhost

          Prefix each printed line with the given hostname (target).
          The hostname will be followed by the separator character.


      --std-format=*

      --std-format=utf8
      --std-format=crlf
      --std-format=raw
      --std-format=unix
      --std-format=CHARSET

          This option is used to specify the general output format for STDOUT
          and STDERR. All results are written to STDOUT,  errors and warnings
          may also be written to STDERR .  The default is ':unix:utf8', which
          is the perlish definition used internally.

          Following values are supported:

          * 'raw'
          * 'unix'      - Print raw data, binary in bytes without conversion.
            Note:  binary here just means characters (as all output is text).

          * 'utf8'      - Convert all characters to UTF-8.
          * 'crlf'      - Use CR LF as end of line.

          * 'CHARSET'   - can be any of the local installed  character sets,
                          like UTF-8, UTF-16LE, CP1252, iso-8859-7, etc..
                          This conversion may print its own warnings.

          The option can be used multiple times with different values.
          To reset the  default behaviour, either  'raw'  or  'unix'  must be
          used. Obviously, they must be used first. All other values are used
          additionally.
          Note:  'utf8' just defines the format of the characters, it does no
          further checks on the converted characters. In contrast, 'UTF-8' is
          used as real encoding and does some checks.

          For more details, please see  "perldoc -f binmode" .

          Currently (Jan. 2018), these options must be used before any --help
          option.

      --win-CR

          Obsolete, please use  --std-format=crlf .

    Options for compatibility with other programs

        Please see other programs for detailed description (if not obvious:).
        Note that often only the long form options are accepted as most short
        form options are ambiguous.
        If other programs use the same option,but with a different behaviour,
        then thes other options are not supported.
        For a list of supported options, please see:

          o-saft.pl --help=alias

        Following list contains only those options not shown with:

          o-saft.pl --help=alias

            # Tool's Option         | (Tool)          o-saft.pl Option
            #-----------------------+--------------+------------------------
            * --checks CMD          | (TLS-Check.pl)  same as  +CMD
            * -h, -h=HOST           | (various tools) same as  --host HOST
            * -p, -p=PORT           | (various tools) same as  --port PORT
            * -t HOST               | (ssldiagnos)    same as  --host HOST
            * --UDP                 | (ssldiagnos)    same as  --udp
            * --timeout, --grep     | (ssltest.pl)    ignored
            * -r,  -s,  -t,  -x     | (ssltest.pl)    ignored
            * --insecure            | (cnark.pl)      ignored
            * --nopct --nocolor     | (ssldiagnos)    ignored
            * -connect, -H, -u, -url, -U            ignored
            * -noSSL                |                 same as  --no-SSL
            * -no_SSL               |                 same as  --no-SSL
            #-----------------------+--------------+------------------------

        For definition of  'SSL'  see  --SSL  and  --no-SSL  above.

    Options for customisation

      --cfg-CFG

          Option for customisation have the general from:  --cfg-CFG=KEY=TEXT
          For general descriptions please see  CUSTOMISATION  section below.

      --cfg-cmd=CMD=LIST

          Redefine list of commands. Sets  '%cfg{cmd-CMD}'  to  'LIST'.
          Commands can be written without the leading  '+'.
          If  CMD  is any of the known internal commands, it will be redifned.
          If  CMD  is a unknown command, it will be created.

          Example:
              --cfg-cmd=sni="sni hostname"
          An example  +preload  can be found in  '.o-saft.pl' .

          To get a list of commands and their settings, use:
              o-saft.pl --help=intern

          Main purpose is to reduce list of commands or to print them sorted.

      --cfg-checks=KEY=TEXT
      --cfg-data=KEY=TEXT

          Redefine texts used for labels in output. Sets '%data{KEY}{txt}'  or
          '%checks{KEY}{txt}'  to  'TEXT'.

          To get a list of preconfigured labels, use:
              o-saft.pl --help=cfg-checks
              o-saft.pl --help=cfg-data

      --cfg-cipher=CIPHER=value

          Redefine the security value (i.e. HIGH) in the cipher description.
          Example:
              --cfg-cipher=NULL-MD5=no-security-at-all

      --cfg-text=KEY=TEXT

          Redefine general texts used in output. Sets '%text{KEY}'  to  'TEXT'.

          To get a list of preconfigured texts, use:
              o-saft.pl --help=cfg-text

          Note that \n, \r and \t are replaced by the corresponding character
          when read from rc-file.

      --cfg-text=FILE

          Read definitions for  '%text{KEY}="my text"' from file  'FILE'.

      --cfg-hint=KEY=TEXT

          Redefine texts used for hints. Sets  '%cfg{hints}{KEY}'  to  'TEXT'.

          To get a list of preconfigured texts, use:
              o-saft.pl --help=cfg-hint

      --cfg-init=KEY=VALUE

          Set the internal  '%cfg' hash. This options is intended for testing
          and debugging only. Please see  TESTING  below.

      --call=METHOD

          See  Options for SSL tool.

      --usr
      --user

          Execute functions defined in  lib/OUsr.pm.

      --usr-*
      --user-*

          Options ignored, but stored as is internal in  $cfg{usr-args} .
          These options can be used in  lib/OUsr.pm  or  lib/OTrace.pm.

      --experimental

          Use experimental functionality.
          Some functionality of this tool is  under development and only used
          when this option is given.

    Options for tracing and debugging

          The terms "trace" and "debug" are used interchangeable herein.  The
          functionality enabled by the options described below is more likely
          considered "tracing".

      --n

          Do not execute, just show commands (only useful in conjunction with
          using openssl).

      Difference --trace vs. --v

          --v  prints more information what actually is done. --trace  prints
          more information about internal data such as procedure names and/or
          variable names with their values.

      --v

      --verbose

          Print more information about checks.

          Note that  --v  is different from  -v  (see above).

      --v-cipher
      --cipher-v

          Print each cipher being checked (with  --ciphermode=openssl  only).

      --trace

          Print debugging messages, function names, variable names or values.

      --trace --trace

          Print more debugging messages and pass 'trace=2' to Net::SSLeay and
          lib/SSLinfo.

      --trace --trace --trace

          Print more debugging messages and pass 'trace=3' to Net::SSLeay and
          lib/SSLinfo.

      --trace --trace --trace --trace

          Print processing of all command-line arguments.

      --trace-cli

          Print complete command-line first. Used for internal testing.

      --trace-arg
      --trace--

          Print command-line argument processing.


      --trace-cmd

          Option obsolete since Version 23.11.23. Please use  --v  instead.

      --trace-key
      --trace@

          Print some internal variable names in output texts (labels).
          Variable names are prefixed to printed line and enclosed in  # .
          Example without  --trace-key :
              Certificate Serial Number:          deadbeef

          Example with     --trace-key :
              #serial#          Certificate Serial Number:          deadbeef

      --trace-time

          Prints trace output with timestamps.

      --trace=VALUE

          Alias for  --trace-VALUE  options (see above).

            # Trace Option      | Alias Option
            #-------------------+-----------------------------
            * --trace=1         | same as  --trace
            * --trace=2         | same as  --trace  --trace
            * --trace=arg       | same as  --trace-arg
            * --trace=cli       | same as  --trace-cli
            * --trace=key       | same as  --trace-key
            * --trace=time      | same as  --trace-time
            #-------------------+-----------------------------

      --hint

          Print hint messages (!!Hint:).

      --no-hint

          Do not print hint messages (!!Hint:).

      --warning

          Print warning messages (**WARNING:).

      --no-warning

          Do not print warning messages (**WARNING:).

      --warnings-dups
      --no-warnings-no-dups

          Do not suppress duplicate warning messages (**WARNING:).
          Warning messages not printed multiple times by default: 303 304 412

      --warning-ignore=NNN
      --ignore-warning=NNN

          Supress printing of warning messages with number NNN (**WARNING:).
          Mainly used for internal testing.

      --quiet
      --silent

          Shortcut for:  --no-warning --no-hint .

      --exit=KEY

          Terminate  o-saft.pl  at specified 'KEY'. Please see  TESTING  below.

    Options vs. Commands

        For compatibility with other programs and lazy users,  some arguments
        looking like options are silently taken as commands.  This means that
        --THIS  becomes  +THIS  then. These options are:
          * --help
          * --abbr
          * --todo
          * --chain
          * --default
          * --fingerprint
          * --list
          * --version

        Take care that this behaviour may be removed in future versions as it
        conflicts with those options and commands which actually exist, like:

        --sni  vs.  +sni


LAZY SYNOPSIS

    Commands

        Following strings are treated as a command instead of target names:
          * ciphers
          * s_client
          * version

        A warning will be printed.

    Options

        We support following options, which are all identical, for lazy users
        and for compatibility with other programs.

      Option variants

          * --port PORT
          * --port=PORT

        This applies to most such options,  --port  is just an example.  When
        used in the rc-file, the  --OPTION=VALUE  variant must be used.

      Option names

        Dash '-', dot '.' and/or underscore '_' in option names are optional,
        all following are the same:
          * --no.dns
          * --no-dns
          * --no_dns
          * --nodns

        This applies to all such options,  --no-dns  is just an example.

    Targets

        Following syntax is supported also:
              o-saft.pl http://some.tld other.tld:3889/some/path?a=b

        Note that only the hostname and the port are used from an URL.

    Options vs. Commands

        See  Options vs. Commands  in  OPTIONS  section above


RESULTS

        All output is designed to be easily parsed by postprocessors.  Please
        see  OUTPUT  section below for details.

        For the results,  we have to distinguish  those  returned by  +cipher
        command  and those from  all other tests and checks like   +check  or
        +info  command.

      +cipher

          The cipher checks will return  one line for each  tested cipher. It
          contains at least the cipher name,  'yes'  or  'no'  whether  it is
          supported or not, and a security qualification. It may look like:
              AES256-SHA       yes    HIGH
              NULL-SHA         no     weak

          Depending on the used  --legacy=*  option the format may differ and
          also contain more information.  For details see  --legacy=*  option
          below.

          The text for security qualifications are (mainly) those returned by
          openssl (version 1.0.1): LOW, MEDIUM, HIGH and WEAK.
          The same texts, but with all lower case characters, are used if the
          qualification was adapted herein. Following rules for adjusting the
          qualification were used:

            * weak:
              ** all *NULL* ciphers
              ** all *RC2* and *RC4* ciphers
              ** all *EXPORT*  ciphers
              ** all *anon* (a.k.a ADH a.k.a DHA) ciphers
              ** all *CBC* and *CBC3* (a.k.a 3DES, EDE-CBC) and DES ciphers
            * low:
            * medium:
              ** all *PSK* ciphers using CBC (assumes that the PSK is secure)
            * high:
              ** all *DHE*AES(128|256)* ciphers
              ** all *CHACHA* ciphers
              ** all *PSK* ciphers (except those using

      +check

          These tests return a line with  a label  describing the test  and a
          test result for it. The  idea is to report  'yes'  if the result is
          considered "secure"  otherwise report  'no'  followed by the reason
          why it's considered insecure. Example of a check considered secure:
              Label of the performed check:           yes

          Example of a check considered insecure:
              Label of the performed check:           no (reason why)

          Note  that there are tests where the results  appear confusing when
          first viewed, like for www.wi.ld:
              Certificate is valid according given hostname:  no (*.wi.ld)
              Certificate's wildcard does not match hostname: yes

          This can for example occur with:
              Certificate Common Name:                *.wi.ld
              Certificate Subject's Alternate Names:  DNS:www.wi.ld

          Please check the result with the  +info  command also to  verify if
          the check sounds reasonable.

      +info

          The test result contains detailed information. The labels there are
          mainly the same as for the  +check  command.

CHECKS

        All SSL related check performed by the tool will be described here.

    General checks

        Lookup the IP of the given hostname (FQDN), and then tries to reverse
        resolve the FQDN again.

    SSL ciphers

        Check which ciphers are supported by target. Please see  RESULTS  for
        details of this check.

    SSL connection

      heartbeat

        Check if "heartbeat" extension is supported by target.

      poodle

        Check if target is vulnerable to POODLE attack (SSLv3 enabled).

      robot

        Check if target is vulnerable to ROBOT attack (server offers ciphers
        with RSA encryption).

      sloth

        Check if target is vulnerable to SLOTH attack  (server offers RSA-MD5
        or ECDSA-MD5 ciphers).

      sweet32

        Check if target is vulnerable to Sweet32 attack (server offers CBC or
        CBC3 or DES or 3DES ciphers).

        Note that FIPS-140 compliance requires 3DES ciphers, hence compliant
        systems are then vulnerable to Sweet32 attacks.

      ALPN

        Check if target supports ALPN. Following messages are evaluated:
              ALPN protocol: h2-14
              No ALPN negotiated

        Please see also  CHECKS  ALPN and NPN  below.

    SSL vulnerabilities

      ADH

        Check if ciphers for anonymous key exchange are supported: ADH|DHA.
        Such key exchanges can be sniffed.

      EDH

        Check if ephemeral ciphers are supported: DHE|EDH.
        They are necessary to support Perfect Forward Secrecy (PFS).

      BEAST

        Check if ciphers with CBC for protocol SSLv1, SSLv3 or TLSv1 are used.
        TLSv1.2 checks are not yet implemented.

      CRIME

        Connection is vulnerable if target supports SSL-level compression, or
        supports SPDY/3 (because SPDY/3 uses compression).
        See http://zoompf.com/2012/09/explaining-the-crime-weakness-in-spdy-and-ssl

        Note: SPDY/3 is only possible if the client explicitely asks for this
        alternate protocol (for example  "openssl ... -nextprotoneg spdy/3").

      DROWN

        Connection is vulnerable if target supports SSLv2.

      FREAK

        Attack against SSL/TLS to downgrade to EXPORT ciphers.
        Currently (2018) a simple check is used:   SSLv3 enabled and EXPORT
        ciphers supported by server.
        See CVE-2015-0204 and https://freakattack.com/ .

      HEARTBLEED

        Check if target is vulnerable to heartbleed attack, see CVE-2014-0160
        and http://heartbleed.com/ .

      HEIST

        Not implemented.

        There are no checks for the HEIST attack implemented, because this is
        an attack on TCP/IP rather than SSL/TLS on top of TCP/IP.

      KCI

        To perform a MiTM attack with Key Compromise Impersonation, the atta-
        cker needs to engage the victim to install and use a client certificate.
        This is considered a low risk and hence not tested here.

      Logjam

        Check if target is vulenerable to Logjam attack.
        Check if target suports  EXPORT ciphers  and/or  DH Parameter is less
        than 2048 bits. ECDH must be greater to 511 bits.

      Lucky13

        Check if CBC ciphers are offered.
        Note the recommendation  to be safe against  Lucky13  was to use  RC4
        ciphers. But they are also subject to attacks (see below).  Hence the
        check is only for CBC ciphers.

      RC4

        Check if RC4 ciphers are supported.
        They are assumed to be broken.
        Note that  +rc4  reports the vulnerabilitiy to the  RC4 Attack, while
        +cipher-rc4  simply reports if  RC4 ciphers are offered.  However the
        check, and hence the result, is the same.

      PFS

        Check if DHE ciphers are used.  Checks also if the TLS session ticket
        is random or not used at all.
        TLSv1.2 checks are not yet implemented.

      POODLE

        Check if target is vulnerable to  POODLE attack (just check if  SSLv3
        is enabled).

      Practical Invalid Curve Attack

        This attack allows an attacker to read the servers private key if the
        server does not check properly the passed points for a ecliptic curve
        when EDH ciphers are used.

        This check will not send multiple invalid points,  but only checks if
        the server closes the connection or responds with no matching cipher.

      ROBOT

        Bleichebacher's Oracle attack against SSL/TLS ciphers.

        Not implemented.
        https://robotattack.org/


      SLOTH

        Currently (2016) we check for ciphers with  ECDSA, RSA-MD5.
        Checking the TLS extension 'tls-unique' is not yet implemented.

      Sweet32

        Currently (2016) we check for ciphers with CBC or CBC3 or DES or 3DES.

      Ticketbleed

        NOT YET IMPLEMENTED
        Check if target is vulnerable to ticketbleed, means that it returns
        up to 31 random bytes from memory as Session Ticket, see CVE-2016-9244
        and https://filippo.io/Ticketbleed/ .

    Target (server) configuration and support

      BEAST, BREACH, CRIME, DROWN, FREAK, Logjam, Lucky13, POODLE, RC4, ROBOT,
      SLOTH, Sweet32

        See above.

      Renegotiation

        Check if the server allows client-side initiated renegotiation.

      Version rollback attacks

        NOT YET IMPLEMENTED
        Check if the server allows changing the protocol.

      DH parameter

        Check if target's DH Parameter is less 512 or 2048 bits.

      SSTP

        Check if target supports SSTP by accepting method SSTP_DUPLEX_POST.

        The check does not send other methods (like CONNECT) to verify if the
        protocol is fully supported.

        Supporting SSTP is considered insecure, because SSTP allows to tunnel
        other, probably insecure, protocols.

    Target (server) certificate

      Certificate Hashes

        Check that fingerprint is not MD5.
        Check that certificate private key signature is SHA2 or better.

      Root CA

        Provided certificate by target should not be a Root CA.

      Self-signed certificate

        Certificate should not be self-signed.

      FQDN is listed in subjectAltname (RFC2818)

        The FQDN must be listed in the certificates subjectAltname.
        The check command  +rfc_2818_names  is based on the info command
        +verify_hostname . The check was added in 05/2017 because browsers
        started to complain if the FQDN is not part of the subjectAltname.

      IP in CommonName or subjectAltname (RFC6125)

        NOT YET IMPLEMENTED

      Basic Constraints

        Certificate extension Basic Constraints should be CA:FALSE.

      OCSP, CRL, CPS

        Certificate should contain URL for OCSP and CRL.

      Private Key encyption

        Certificates signature key supports encryption.

      Private Key encyption well known

        Certificates signature key encryption algorithm is well known.

      Public Key encyption

        Certificates public key supports encryption.

      Public Key encyption well known

        Certificates public key encryption algorithm is well known.


      Public Key Modulus Exponent size

        The modulus exponent should be = 65537 as it is a prime number and an
        easy to calculate exponent.
        If the exponent is less than 65537, "Boradcast" attacks are possible.

        However, some (mainly historic) SSL implementations may have problems
        to connect because they are not able to do the crypt mathematics with
        exponenents larger than 65536.

        If ecliptic curves are used, the result for these checks is always
        'no (<<N/A ...)'.

      Sizes and Lengths of Certificate Settings

        Serial Number <= 20 octets (RFC5280, 4.1.2.2.  Serial Number)

        ...

      DV-SSL - Domain Validation Certificate

        The Certificate must provide:
          * Common Name '/CN=' field
          * Common Name '/CN=' in 'subject' or 'subjectAltname' field
          * Domain name in 'commonName' or 'altname' field

      EV-SSL - Extended Validation Certificate

        This check is performed according the requirements defined by the CA/
        Browser Forum  https://www.cabforum.org/contents.html .
        The certificate must provide:
          * DV - Domain Validation Certificate (see above)
          * Organization name '/O=' or 'subject' field
          * Organization name must be less to 64 characters
          * Business Category '/businessCategory=' in 'subject' field
          * Registration Number '/serialNumber=' in 'subject' field
          * Address of Place of Business in 'subject' field

        Required are: '/C=', '/ST=', '/L='

        Optional are: '/street=', '/postalCode='

          * Validation period does not exceed 27 month

        See  LIMITATIONS  also.

    Target (server) HTTP(S) support

      STS header (see RFC 6797)

        Using STS is no perfect security.  While the very first request using
        http: is always prone to a MiTM attack, MiTM is possible to following
        requests again, if STS is not well implemented on the server.
          * Request with http: should be redirected to https:
          * Redirects should use status code 301 (even others will work)
          * Redirect's Location header must contain schema https:
          * Redirect's Location header must redirect to same FQDN
          * Redirect may use Refresh instead of Location header (not RFC6797)
          * Redirects from HTTP must not contain STS header
          * Answer from redirected page (HTTPS) must contain STS header
          * Answer from redirected page for IP must not contain STS header
          * STS header must contain includeSubDirectoy directive
          * STS header max-age should be less than 1 month
          * STS must not be set in http-equiv attribute of a meta TAG

      STS header preload attribute (+preload)

        To satisfy the requirements on  https://hstspreload.appspot.com/  the
        HSTS header must:
          * have the max-age with at least 18 weeks (10886400 seconds)
          * have the includeSubDomains attribute
          * have the preload attribute
          * redirect to https first, then to sub-domains (if redirected)
          * have an HSTS header in each redirect to https.

        Additionally, the site must have:
          * a valid certificate
          * serve all subdomains over https.

        Except the last requirement,  +preload  will do the checks.
        Note that  +preload  is defined in  '.o-saft.pl'  only.

      Public Key Pins header
        TBD - to be described ...

    Sizes

        Mainly in the certificate various counts, lengths and sizes of values
        are checked and reported. All commands for these checks start with
        '+cnt_'  or  '+len_'.  Up to now, there is no  'yes'  or  'no'  value
        for these checks.

        Following commands will check the value to be in  a specific range to
        become  'yes'  or  'no':
          * +sts_maxage1d       - 'yes' if HSTS maxage < 1 day
          * +sts_maxage1m       - 'yes' if HSTS maxage < 1 month
          * +sts_maxage1y       - 'yes' if HSTS maxage < 1 year
          * +sts_maxage18       - 'yes' if HSTS maxage < 18 weeks (5 months)
          * +sts_maxagexy       - 'yes' if HSTS maxage > 1 year
          * +modulus_exp_1      - Public Key Modulus Exponent <>1
          * +modulus_exp_65537  - Public Key Modulus Exponent =65537
          * +modulus_exp_oldssl - Public Key Modulus Exponent <65537
          * +modulus_size_oldssl - Public Key Modulus <16385 bits

        For some details of these checks, please see the description above at
          Public Key Modulus Exponent size

        The recommendations for  DH parameters (RSA and ecliptice curve)  are
        are checked as follows:
          * +dh_512             - DH Parameter >= 512 bits
          * +dh_2048            - DH Parameter >= 2048 bits
          * +ecdh_256           - DH Parameter >= 256 bits (ECDH)
          * +ecdh_512           - DH Parameter >= 512 bits (ECDH)
        Note that only one of the checks  '+dh_*'  and  '+ecdh_*'  can return
        'yes'.

    ALPN and NPN

        The commands for the checks to report  'yes'  or  'no', are  +hasalpn
        and  +hasnpn.

        Both, the Application Layer Protocol Negotiation (ALPN) and the  Next
        Protocol Negotiation (NPN) will be tested. The commands for that are:
          * +alpns
          * +npns

        Each, ALPN and NPN, is tested separately with all known protocols.
        The test sets only one protocol,  tries to make a connection and then
        checks if the protocol was accepted by the server. The collected list
        of protocols will be printed with the aforementioned commands, or the
        +info  command. Note the difference for the commands  +next_protocols
        and  +alpns, where  +next_protocols  simply reports  what  the server
        itself advertises, while  +alpns  reports what the server supports if
        asked for.

    Compliances

        Note that it is not possible to satisfy all following compliances.
        Best match is: 'PSF' and 'ISM' and 'PCI' and 'lazy BSI TR-02102-2'.
        In general it is difficult to satisfy all conditions of a compliance,
        and it is also difficult to check  all these conditions.  That is why
        some compliance checks are not completely implemented.
        For details see below please.

        Also note that in the  rc-file  the output of results for some checks
        is disabled by default. A  '!!Hint:'  message will be printed, if any
        of these checks are used.

          * FIPS-140
          * ISM
          * PCI
          * BSI TR-02102-2 (2016-01)
          * BSI TR-03116-4
          * RFC 2818
          * RFC 6125
          * RFC 6797
          * RFC 7525

      BSI TR-02102-2 (+tr-02102+ +tr-02102- +bsi)
        Checks if connection and ciphers are compliant according TR-02102-2,
        see https://www.bsi.bund.de/SharedDocs/Downloads/DE/BSI/Publikationen
        /TechnischeRichtlinien/TR02102/BSI-TR-02102-2_pdf.pdf?__blob=publicationFile

        (following headlines are taken from TR-02102-2 Version 2016-01)

        3.1.3 Schlüssellängen bei EC-Verfahren
die EC-Verfahren ...  und weitere Erläuterungen siehe Bemerkung 4 in Kapitel 3 in [TR-02102-1] .

        3.2   SSL/TLS_Versionen

          Only TLSv1.2 allowed (except for  +tr-02102-  which also allows
          TLSv1.1)

        3.3.1 Empfohlene Cipher Suites

          Allows only *DHE-*-SHA256, *DHE-*-SHA384, *DH-*-SHA256 and
          *DH-*-SHA384 ciphers and PSK ciphers with ephermeral keys.
          For  +tr-02102+  they must be AES-GCM,  +tr02102- also allows
          AES-CBC.

        3.3.2 Übergangsregelungen

          SHA1 temporary allowed. SHA256 and SHA384 recommended.
          RC4 not reocmmended.
          Use of SHA1 will only be checked for  +tr-02102+

        3.4.1 Session Renegotation

          Only server-side (secure) renegotiation allowed (see RFC 5746).

        3.4.2 Verkürzung der HMAC-Ausgabe

          Truncated HMAC according RFC 6066 not recommended.

        3.4.3 TLS-Kompression und der CRIME-Angriff

          No TLS compression.

        3.4.4 Der Lucky13-Angriff
        3.4.5 Die "Encrypt-then-MAC"-Erweiterung

          Use of AES-GCM ciphers only.
          Use of Encrypt-then-MAC according RFC 7366 cannot be checked.

        3.4.6 Die Heartbeat-Erweiterung

          Target must not support the heartbeat extension.

        3.4.7 Die Extended Master Secret Extension

          Use of Extended Master Secret Extension according RFC 7627 cannot
          be checked.

        3.5 Authentisierung der Kommunikationspartner

          Not checked as only applicable for VPN connections.

        3.6 Domainparameter und Schlüssellängen

          Check if signature key is > 2048 bits.


        3.6.1 Verwendung von elliptischen Kurven

          **NOT YET IMPLEMENTED**

          Use only following curves according RFC 5639 and RFC 7027:
          brainpoolP256r1, brainpoolP384r1, brainpoolP512r1

          Use of secp256r1 and secp384r1  temporary allowed.

        4.1 Schlüsselspeicherung

          This requirement is not testable from remote.

        4.2 Umgang mit Ephemeralschlüsseln

          This requirement is not testable from remote.

        4.3 Zufallszahlen

          This requirement is not testable from remote.

      BSI TR-03116-4 (+tr-03116+ +tr-03116- +bsi)
        Checks if connection and ciphers are compliant according TR-03116-4,
        see https://www.bsi.bund.de/SharedDocs/Downloads/DE/BSI/Publikationen
        /TechnischeRichtlinien/TR03116/BSI-TR-03116-4.pdf?__blob=publicationFile

        (following headlines are taken from there)

        2.1.1 TLS-Versionen und Sessions

          Allows only TLS 1.2.

        2.1.2 Cipher Suites

          Cipher suites must be ECDHE-ECDSA or -RSA with AES128 and SHA265.
          For curiosity, stronger cipher suites with AES256 and/or SHA384 are
          not not allowed. To follow this curiosity the  +tr-03116-  (lazy)
          check allows the stronger cipher suites ;-)

        2.1.1 TLS-Versionen und Sessions

          The TLS session lifetime must not exceed 2 days.

        2.1.4.2 Encrypt-then-MAC-Extension

        2.1.4.3 OCSP-Stapling

          MUST have 'OCSP Stapling URL'.

        4.1.1 Zertifizierungsstellen/Vertrauensanker

          Certificate must provide all root CAs. (NOT YET IMPLEMENTED).

          Should use a small certificate trust chain.

        4.1.2 Zertifikate

          Must have 'CRLDistributionPoint' or 'AuthorityInfoAccess'.

          End-user certificate must not be valid longer than 3 years.
          Root-CA certificate must not be valid longer than 5 years.

          Certificate extension 'pathLenConstraint' must exist, and should be
          a small value ("small" is not defined).

          All certificates must contain the extension 'KeyUsage'.

          Wildcards for 'CN' or 'Subject' or 'SubjectAltName' are not allowed
          in any certificate.

          EV certificates are recommended (NOT YET checked properly).

        4.1.3 Zertifikatsverifikation

          Must verify all certificates in the chain down to their root-CA.
          (NOT YET IMPLEMENTED).

          Certificate must be valid according issue and expire date.

          All Checks must be doen for all certificates in the chain.

        4.1.4 Domainparameter und Schlüssellängen

          This requirement is not testable from remote.

        4 5.2 Zufallszahlen

          This requirement is not testable from remote.

      RFC 2818 (+rfc2818)
        Check if the FQDN is listed in the certificates 'subjectAltname'.

      RFC 6125 (+rfc6125)
        Checks values 'CommonName', 'Subject' and 'SubjectAltname'  of the
        certificate for:
           * must all be valid characters for DNS
           * must not contain more than one wildcard
           * must not contain invalid wildcards
           * must not contain invalid IDN characters

      RFC 6797 (+rfc6797)
        Same as STS header  +hsts .

      RFC 7525 (+rfc7525)
        Checks if connection and ciphers are compliant according RFC 7525.
        See http://tools.ietf.org/rfc/rfc7525.txt
        (following headlines are taken from there)

        3.1.1.  SSL/TLS Protocol Versions

          SSLv2 and SSLv3 must not be supportetd.
          TLSv1 should only be supported if there is no TLSv1.1 or TLSv1.2.
          Either TLSv1.1 or TLSv1.2 must be supported, preferred is TLSv1.2.

        3.1.2.  DTLS Protocol Versions

          DTLSv1 and DTLSv1.1 must not be supported.

        3.1.3.  Fallback to Lower Versions

          (check implecitely done by 3.1.1, see above)

        3.2.  Strict TLS

          Check if server provides Strict Transport Security.
          ('STARTTLS' check NOT YET IMPLEMENTED).

        3.3.  Compression

          Compression on TLS must not be supported.

        3.4.  TLS Session Resumption

          Server must support resumtion and random session tickets.
          (Randomnes of session tickets implemented YET experimental.)

          Check if ticket is authenticated and encrypted NOT YET IMPLEMENTED.

        3.5.  TLS Renegotiation

          Server must support renegotiation.

        3.6.  Server Name Indication

          (Check for SNI support implemented experimental.)

        4.  Recommendations: Cipher Suites

        4.1.  General Guidelines
        4.2.  Recommended Cipher Suites

          Check for recommended ciphers.

        4.3.  Public Key Length

          DH parameter must be at least 256 bits or 2048 bits with EC.
          (Check currently, 4/2016, based on openssl which may not provide DH
           parameters for all ciphers.)

        4.5.  Truncated HMAC

          TLS extension "truncated hmac" must not be used.

        6.  Security Considerations
        6.1.  Host Name Validation

          Given hostname must matches hostname in certificate's subject.

        6.2.  AES-GCM
        6.3.  Forward Secrecy
        6.4.  Diffie-Hellman Exponent Reuse
          (NOT YET IMPLEMENTED).

        6.5.  Certificate Revocation

          OCSP and CRL Distrbution Point in cetificate must be defined.




OUTPUT

        All output is designed to make it  easily parsable by postprocessors.
        Following rules are used:
          * Lines for formatting or header lines start with  '='.
          * Lines for verbosity or tracing start with  '#'.
          * Errors, warnings and information start with  '**'.
          * Hints start with '!!'.
          * Empty lines are comments ;-)
          * Label texts end with a separation character; default is  ':'.
          * Label and value for all checks are separated by at least one  TAB
            character.
          * Texts for additional information are enclosed in '<<'  and  '>>'.
          * 'N/A'  is used  when no proper information was found or provided.
            Replace  'N/A'  by whatever you think is adequate:  "No answer",
            "Not available",  "Not applicable",  ...

        Examples:
              === Title line ===
              = this is a comment

              Label for information or check:  TABresult
              !!Hint: above result depends on the target

        For more details on these lines, please refer to  RESULTS  above.

        When used in  --legacy=full  or  --legacy=simple mode, the output may
        contain formatting lines for better (human) readability.

    Errors, warnings, hints

        Errors, warnings and hints may be part of the output as needed. While
        errors and warnings are printed immediately as they occour during the
        program flow, hints are printed right after the corresponding result.

        Errors and warnings start with a unique  3-digit number.  The numbers
        are grouped as follows:

         #-------------+------------------------------------
          number range | description
         #-------------+------------------------------------
                0xx    | startup check, options, arguments
                1xx    | check (runtime) functionality
                2xx    | loop targets (hosts)
                3xx    | connect functions
                4xx    | cipher check functions
                5xx    | inernal check functions
                6xx    | check functions
                8xx    | print functions
         #-------------+------------------------------------

        Hints print an additional explanation of a specific result.  They are
        are defined statically in the program code, or can be added on demand
        by using the option  --cfg-hint=KEY=TEXT .

    Postprocessing output

        It is recommended to use the   --legacy=quick   option, if the output
        should be postprocessed, as it omits the default separation character
        (':' , see above) and just uses on single tab character (0x09, \t  or
        TAB) to separate the label text from the text of the result. Example:
              Label of the performed checkTABresult

        More examples for postprocessing the output can be found here:
              https://github.com/OWASP/O-Saft/blob/master/usr



EXIT STATUS

        Following exit codes are used:

          * 0   - normal usage and execution
          * 2   - command-line parsing failed, command or option missing
          * >0  - only if  --exitcode  was used

ENVIRONMENT

        Following environment variables are incorporated:

          * LD_LIBRARY_PATH - used and extended with definitions from options
          * OPENSSL         - if set, full path to openssl executable
          * OPENSSL_CONF    - if set, full path to openssl's openssl.cnf or
                              directory where to find openssl.cnf
          * OSAFT_CONFIG    - if set to an existing file, use it as rc-file
                              don't read any file if given file doesn't exist
                              file will be overwritten with  --rc=FILE option
          * OSAFT_OPTIONS   - if set, all words will be used as  command-line
                              argument (option, command, target)
                              note that whitespace characters aren't possible
                              in given arguments, 'cause each word is used as
                              a single argument
          * OSAFT_MAKE      - if set, some  random values  in the result  are
                              replaced by constant strings; it is set for all
                              targets in all Makefile*


CUSTOMISATION

        This tool can be customised as follows:

        * Using command-line options

            This is a simple way to redefine  specific settings.  Please  see
            CONFIGURATION OPTIONS  below.

        * Using configuration file

            A configuration file can contain multiple configuration settings.
            Syntax is simply  KEY=VALUE. Please see CONFIGURATION FILE below.

        * Using resource files

            A resource file can contain multiple command-line options. Syntax
            is the same as for command-line options iteself.  Each  directory
            may contain its own resource file. Please see rc-file below.

        * Using debugging files

            These files are - nomen est omen - used for debugging purposes.
            However, they can be (mis-)used to redefine all settings too.
            Please see  DEBUG-FILE  below.

        * Using user specified code

            This file contains  user specified  program code.  It can also be
            (mis-)used to redefine all settings. Please see USER-FILE  below.

        Customisation is done by redefining values in internal data structure
        which are:  %cfg,  %data,  %checks,  %text.

        Unless used in  DEBUG-FILE  or  USER-FILE,  there is  no need to know
        these internal data structures or the names of variables; the options
        will set the  proper values.  The key names being part of the option,
        are printed in output with the  --trace-key  option.

        Texts (values) of keys in  '%data'  are those  used in  output of the
        "Information" section.  The texts of keys in  '%checks'  are used for
        output in "Performed Checks" section.  Texts of keys in  '%text'  are
        used for additional information lines or texts (mainly beginning with
        '=').

     Configuration file vs. RC-FILE vs. DEBUG-FILE

        * CONFIGURATION FILE

            Configuration files must be specified with one of the  --cfg-*
            options. The specified file can be a valid path. Please note that
            only the characters:  a-zA-Z_0-9,.\/()-  are allowed as pathname.
            Syntax in configuration file is:  'KEY=VALUE'  where 'KEY' is any
            key as used in internal data structure.

        * RC-FILE

            Resource files are searched for and used automatically.
            For details see  RC-FILE  below.

        * DEBUG-FILE

            Debug files are searched for and used automatically.
            For details see  DEBUG-FILE  below.

        * USER-FILE

            The user program file is included only  if the  --usr  option was
            used. For details see  USER-FILE  below.

        DEBUG-FILE  and  USER-FILE  will be searched for in paths of '@INC'.


    CONFIGURATION OPTIONS

        Configuration options are used to redefine  texts and labels or score
        settings used in output. The options are:
          * --cfg-cmd=CMD=LIST
          * --cfg-checks=KEY=TEXT
          * --cfg-data=KEY=TEXT
          * --cfg-hint=KEY=TEXT
          * --cfg-text=KEY=TEXT
          * --cfg-cipher=CIPHER=TEXT

        'KEY'  is the key used in the internal data structure, and  'TEXT' is
        the value to be set for this key.  Note that unknown keys are ignored
        silently.

        If  'KEY=TEXT'  is an existing filename, all lines from that file are
        read and set. For details see  CONFIGURATION FILE  below.

        'CIPHER'  must be a valid cipher suite name as shown with:

              o-saft.pl ciphers

        Note that such configuration options should be used before any --help
        or  --help=*  option, otherwise the changed setting is not visible.

    CONFIGURATION FILE

        Note that the file can contain  'KEY=TEXT' pairs for any kind of the
        configuration as given by the  --cfg-CFG  option.

        For example  when used with  --cfg-text=FILE  only values for  %text
        will be set, when used with  --cfg-data=FILE  only values for  %data
        will be set, and so on. 'KEY' will not be used when 'KEY=TEXT' is an
        existing filename.  It is recommended to use a non-existing key, for
        example  --cfg-text=my_file=some/path/to/private/file .

    RC-FILE

        The rc-file will be searched in following sources:

              a. file given in environment variable OSAFT_CONFIG
              b. default name: program file prefixed by a '.' (dot) 
              c. file given with  --rc=FILE  option

        By default only '.o-saft.pl' in the working directory is used.

        A  rc-file  can contain any of the commands and options valid for the
        tool itself. The syntax for them is the same as on command-line. Each
        command or option must be in a single line. Any empty or comment line
        will be ignored. Comment lines start with  '#'  or  '='.

        Note that options with arguments must be used as  'KEY=VALUE' instead
        of  'KEY VALUE'.

        Configurations options must be written like '--cfg-CFG=KEY=VALUE'.
        Where  'CFG'  is any of:  'cmd', 'check', 'data', 'text'  and  'KEY'
        is any key from internal data structure (see above).

        All commands and options given on command-line will  overwrite  those
        found in the rc-file.

    DEBUG-FILE

        All debugging functionality is defined in  lib/OTrace.pm .

        Syntax in this file is Perl code.  For details see  DEBUG  below.

    USER-FILE

        All user functionality is defined in   lib/OUsr.pm .

        Syntax in this file is Perl code.

        All functions defined in   lib/OUsr.pm   are called  when the  option
        --usr  was used. The functions are defined as empty stub and any code
        can be inserted as need.  Please see   perldoc lib/OUsr.pm   when and
        how these functions are called.

    SHELL TWEAKS

        Configuring the shell environment where the tool is startet,  must be
        done before the tool starts. It isn't a task for the tool itself, but
        it can simplify your life, somehow.

        There exist customisations for some commonly used shells,  please see
        the files in the ./usr/ directory.

    COMMANDS

        The option  --cfg-cmd=CMD=LIST  can be used to define own commands.
        When configuring own commands,  CMD  must not be  one of the commands
        listed with  --help=intern  and CMD  must constist only of digits and
        letters.

        Examples in  '.o-saft.pl'  are  +preload  and  +ciphercheck .


CIPHER NAMES

        While the SSL/TLS protocol uses integer numbers to identify  ciphers,
        almost all tools use some kind of  "human readable"  texts for cipher
        names.

        These numbers (which are most likely written  as hex values in source
        code and documentations) are the only true identifier, and we have to
        rely on the tools that they use the proper integers.

        As such integer or hex numbers are difficult to handle by humans,  we
        decided to use human readable texts. Unfortunately no common standard
        exists how to construct the names and map them to the correct number.
        Some, but by far not all, oddities are described in  Name rodeo.

        The rules for specifying cipher names are:
          1) textual names as defined by IANA (see [IANA])
          2) mapping of names and numbers as defined by IANA (see [IANA])
          3) '-'  and  '_'  are treated the same
          4) abbreviations are allowed, as long as they are unique
          5) beside IANA, OpenSSL's cipher names are preferred
          6) name variants are supported, as long as they are unique
          7) hex numbers can be used
          8) our internal hex numbers for ciphers are like '0x0300CCA9'

        [IANA]    http://www.iana.org/assignments/tls-parameters/tls-parameters.txt August 2022

        [openssl] ... openssl 1.0.1

        If in any doubt, use any of the  provided commands or options to list
        to show our known ciphers. For example:

              o-saft.pl --test-ciphers-show  # or any other  --test-ciphers-*
              o-saft.pl --list
              o-saft.pl --help=ciphers-text
              o-saft.pl ciphers -V

        Use  --help=regex  to see which regex are used to handle all variants
        of cipher suite names herein.

        Mind the traps and dragons with cipher names and what number they are
        actually mapped to. In particular when  --lib,  --exe  or  --openssl
        options are in use. Always use these options with  +list command too.

    Name rodeo

        As said above, the  SSL/TLS protocol uses integer numbers to identify
        ciphers, but almost all tools use some kind of  human readable  texts
        for cipher names.

        For example the cipher commonly known as 'DES-CBC3-SHA' is identified
        by '0x020701c0' (in openssl) and has 'SSL2_DES_192_EDE3_CBC_WITH_SHA'
        as constant name. A definition is missing in IANA, but there is
        'TLS_RSA_WITH_3DES_EDE_CBC_SHA'.  There is also '0x000A' for the same
        cipher 'DES-CBC3-SHA'.  Both are valid, first one if used with SSLv2,
        and second one when used with SSLv3.
        It's the responsibility of each tool to map the human readable cipher
        name to the correct (hex, integer) identifier.

        For example Firefox uses  'dhe_dss_des_ede3_sha',  which is what?

        Furthermore, there are different acronyms for the same thing in use.
        For example  'DHE'  and  'EDH'  both mean "Ephemeral Diffie-Hellman".
        Comments in the "openssl(1)"  sources mention this.  And for curiosity
        these sources use both in cypher names, but allow  'EDH'  as shortcut
        only in openssl's "ciphers"  command. Wonder about (up to 1.0.1h):
              openssl ciphers -V EDH
              openssl ciphers -V DHE
              openssl ciphers -V EECDH
              openssl ciphers -V ECDHE

        Next example is  'ADH'  which is also known as  'DH_anon' or 'DHAnon'
        or  'DHA'  or  'ANON_DH'.

        You think this is enough? Then have a look how many acronyms are used
        for  "Tripple DES".

        Compared to above, the interchangeable use of  '-'  vs.  '_' in human
        readable cipher names is just a very simple one. However, see openssl
        again what following means (returns):
              openssl ciphers -v RC4-MD5
              openssl ciphers -v RC4+MD5
              openssl ciphers -v RC4:-MD5
              openssl ciphers -v RC4:!MD5
              openssl ciphers -v RC4!MD5

        Looking at all these oddities, it would be nice to have a common unique
        naming scheme for cipher names. We have not.  As the SSL/TLS protocol
        just uses a number, it would be natural to use the number as uniq key
        for all cipher names, at least as key in our internal sources.

        Unfortunately, the assignment of ciphers to numbers  changed over the
        years, which means that the same number refers to a  different cipher
        depending on the standard, and/or tool, or version of a tool you use.

        As a result, we cannot use human readable cipher names as  identifier
        (a.k.a unique key), as there are to many aliases for the same cipher.
        And also the number  cannot be used  as unique key, as a key may have
        multiple ciphers assigned.

        The default behaviour will be to use the cipher names like "openssl(1)"
        does. If a name is ambigous, the first matching will be choosen. This
        -first matching- only applies to names provided by the user by option
        or whatever, internally the latest IANA number will be used,  because
        they have the most less ambiguities.


KNOWN PROBLEMS

        This section describes knwon problems, and known error messages which
        may occour when using o-saft.pl. This sections can be used as FAQ too
        as it gives hints and workarounds.

    +cipher hangs

        There're various reason why this may happen:

          * target does not support SSL protocol on specified port
          * target has a rate limitation or IPS is in place

        Start the test with the  --v  option  which then reports the protocol
        currently tested, like:

          **INFO:   test 2640 ciphers for DTLSv12 ... (SSLhello)

        Workaround: disable the protocol with the  --noSSL  option  (would be
        --no-dtls12  in this example).
        Most likely this happens with old servers not supporting DTLS or with
        modern servers not supporting SSLv2, SSLv3.

        Other options to test are  --timeout=SEC  or  --connect-delay=SEC .

    Segmentation fault

        Sometimes  the program terminates with a  'Segmentation fault'.  This
        mainly happens if the target does not return certificate information.
        If so, the  --no-cert  option may help.

    **WARNING: 311: empty result from openssl; ignored at ...

        This most likely occurs when the  provided cipher is  not accepted by
        the server, or the server expects client certificates.

    **WARNING: 311: unknown result from openssl; ignored at ...

        This most likely occurs when the "openssl(1)" executable is used with a
        very slow connection. Typically the reason is a connection timeout.
        Try to use  --timeout=SEC  option.
        To get more information, use  --v --v  and/or  --trace  also.

    **WARNING: 016: undefined cipher description

        May occour if ciphers are checked, but no description is available for
        them herein. This results in printed cipher checks like:
              EXP-KRB5-RC4-MD5                no       <<undef>>

        instead of:
              EXP-KRB5-RC4-MD5                no       weak

    **WARNING: 205: Can't make a connection to your.tld:443; no initial data
    **WARNING: 205: Can't make a connection to your.tld:443; target ignored

        This message occours if the underlaying  SSL library (i.e. libssl.a)
        was not able to connect to the target. Known observed reasons are:
          * target does not support SSL protocol on specified port
          * target expects a client certificate in ClientHello message

        More details why the connection failed can be seen using  --trace=2 .


    Use of uninitialized value $headers in split ... do_httpx2.al)

        The warning message (like follows or similar):

              Use of uninitialized value $headers in split at blib/lib/Net/SSLeay.pm
              (autosplit into blib/lib/auto/Net/SSLeay/do_httpx2.al) line 1290.

        occurs if the target refused a connection on port 80.
        This is considered a bug in "Net::SSLeay(3pm)".
        Workaround to get rid of this message: use  --no-http  option.

    invalid SSL_version specified at ... IO/Socket/SSL.pm

        This error may occur on systems where a specific  SSL version is not
        supported. Subject are mainly  SSLv2, SSLv3 TLSv1.3 and DTLSv1.
        For DTLSv1 the full message looks like:
              invalid SSL_version specified at C:/programs/perl/perl/vendor/lib/IO/Socket/SSL.

        See also  Note on SSL versions .

        Workaround: use option:  --no-sslv2  --no-sslv3  --no-tlsv13  --no-dtlsv1

    Use of uninitialized value $_[0] in length at (eval 4) line 1.

        This warning occours with IO::Socket::SSL 1.967, reason is unknown.
        It seems not to harm functionality, hence no workaround, just ignore.

    Use of uninitialized value in subroutine entry at lib/IO/Socket/SSL.pm line 430.

        Some versions of  IO::Socket::SSL return this error message if  *-MD5
        ciphers are used with other protocols than SSLv2.

        Workaround: use  --no-md5-cipher  option.

    Can't locate auto/Net/SSLeay/CTX_v2_new.al in @INC ...

        Underlaying library doesn't support the required SSL version.
        See also  Note on SSL versions .

        Workaround: use  --ssl-lazy option, or corresponding --no-SSL option.

    Read error: Connection reset by peer (,199725) at blib/lib/Net/SSLeay.pm\
    (autosplit into blib/lib/auto/Net/SSLeay/tcp_read_all.al) line 535.

        Error reported by some Net::SSLeay versions. Reason may be a timeout.
        This error cannot be omitted or handled properly.

        Workaround: try to use same call again (no guarantee, unfortunatelly)

    Odd number of elements in anonymous hash at lib/SSLinfo.pm line 1613.

        This warning from perl have been observed  when the connection to the
        target to check for supported ciphers cannot be established.

        This message can be ignored.

    openssl: ...some/path.../libssl.so.1.0.0: no version information available (required by openssl)

        Mismatch of  openssl executable  and loaded underlaying library. This
        most likely happens when options  --lib=PATH  and/or  --exe=PATH  are
        used.  See also  Note on SSL versions .

        Hint: use following commands to get information about used libraries:
              o-saft.pl +version
              o-saft.pl --v --v +version

    Integer overflow in hexadecimal number at ...

        This error message may occour on  32-bit systems if perl was not com-
        piled with proper options. I.g. perl automatically converts the value
        to a floating pont number.
        Please report a bug with output of following command:
              o-saft.pl +s_client +dump your.tld

    openssl did not return DH Paramter>>

        Text may be part of a value. This means that all checks according  DH
        parameters and logkam attack cannot be done.

        Workaround: try to use  --openssl=TOOL  option.

        This text may appear in any of the compliance checks (like  +rfc7525)
        which may be a false positive.  For these checks openssl is also used
        to get the DH Parameter.

        Workaround: not available yet

    No output with  +help  and/or  --help=todo

        On some (mainly Windows-based) systems using
              o-saft.pl +help
              o-saft.pl --help

        does not print anything.

        Workaround: use  --v  option.
              o-saft.pl +help --v

        or
              o-saft.pl +help | more

    Character set (like UTF-8) not recognised in some tools

        Some tools  do not display all characters properly,  for example some
        versions of  podviewer.  It is not the obligation of this tool to fix
        well known bugs in other tools. However, we can offer workarounds.

        Workaround: generate the affected output using  --std-format=*  options
        For example:
              o-saft.pl --no-rc --std-format=raw --help=gen-pod

    **WARNING: on MSWin32 additional option  --v  required, sometimes ...

        On some (mainly Windows-based) systems  this may happen  when calling
        for example:
              o-saft.pl --help=FAQ

        which then may produce:
              **WARNING: on MSWin32 additional option  --v  required, sometimes ...
              === reading: ./.o-saft.pl (RC-FILE done) ===
              === reading: lib/SSLinfo.pm (O-Saft module done) ===
              **USAGE: no command given
              # most common usage:
                o-saft.pl +info   your.tld
                o-saft.pl +check  your.tld
                o-saft.pl +cipher your.tld
              # for more help use:
                o-saft.pl --help

        Workaround: use full path to perl.exe, for example
              C:\Programs\perl\bin\perl.exe o-saft.pl --help=FAQ


    Performance problems

        There are various reasons when the program responds slow, or seems to
        hang. Performance issues are most likely a target-side problem.  Most
        common reasons are (no specific order):

          a) DNS resolver problems
             Try with  --no-dns

          b) target does not accept connections for https
             Try with  --no-http

          c) target's certificate is not valid
             Try with  --no-cert

          d) target expects that the client provides a client certificate
             No option provided yet ...

          e) target does not handle Server Name Indication (SNI)
             Try with  --no-sni

          f) use of external "openssl(1)" executable
             Use  --no-openssl

          g) target does not respond at all and/or blocks
             Use  --ssl-error
             For a detailed description, please see Connection problems.

        Other options which may help to get closer to the problem's cause:
        --trace-time,  --timeout=SEC,  --trace

        Using  --trace-time   should show following times:
              DNS:             1 .. 10 sec
              need_default:    <5 sec
              need_cipher:     1 ..299 sec (+cipher with socket)
              no SNI:          1 .. 10 sec
              connection test: 1 ..  5 sec
              prepare checks:  2 .. 20 sec
                  checkalpn.   1 .. 15 sec
                  checkprot.   1 .. 15 sec
              cipher:          <1 sec
              info:            <1 sec
              check:           <1 sec


LIMITATIONS

    Commands

        Some commands cannot be used together with others, for example:
        +cipher,  +ciphers,  +list,  +libversion,  +version,  +check,  +help,
        +protocols .

        +quick  should not be used together with other commands, it returns
        strange output then. It is the only command which allows  +cipher
        together with other commands.

        +protocols  requires "openssl(1)"  with support for  '-nextprotoneg'
        option. Otherwise the value will be empty.

    Options

        The option  --port=PORT  must precede  --host=HOST  for a target like
        HOST:PORT  .

        The characters  '+' and '='  cannot be used for  --separator=CHAR
        option.

        Following strings should not be used in any value for options:
          '+check', '+info', '+quick', '--header'
        as they my trigger the  --header   option unintentional.

        The used "timeout(1)"  command cannot be defined with a full path like
       "openssl(1)"  can with the  --openssl=path/to/openssl .

        --cfg-text=FILE  cannot be used to redefine the texts  'yes' and 'no'
        as used in the output for  +cipher  command.

        --cipher=CIPHER  accepts keys, names and patterns for ciphers.
        Keys must start with '0x' followed by exactly 8 uppercase hex chars.
        If 'CIPHER' should match a cipher suite name, it must be written with
        uppercase letters. If it should match a predefined pattern it must be
        written with lowercase letters.
        Note that currently not all OpenSSL-style patterns are supported.

        --cipherrange=RANGE  accepts only lowercase names.

    Checks (general)

      +constraints

          This check is only done for the certificate provided by the target.
          All other certificate in the chain are not checked.

          This is currently (2018) a limitation in  o-saft.pl.

    Broken pipe

        This error message most likely means that the connection to specified
        target was not possible (firewall or whatever reason).

    Target Certificate Chain Verification

        The systems default capabilities for example  libssl.so, openssl, are
        used to verify the target's certificate chain.  Unfortunately various
        systems have implemented different  approaches and rules how identify
        and how to report a successful verification.  Consequently, this tool
        can only return the same information  about the chain verification as
        the used underlying tools. If that information is trustworthy depends
        on how trustworthy the tools are.

        These limitations apply to following commands:
          * +verify
          * +selfsigned

        Following commands and options are useful to get more information:
          * +chain_verify,  +verify,  +error_verify,  +chain,  +s_client
          * --ca-file,  --ca-path,  --ca-depth

    User provided files

        Please note that there cannot be any guarantee that the code provided
        in the  DEBUG-FILE lib/OTrace.pm  or the  USER-FILE lib/OUsr.pm  will
        work flawless. Obviously this is the user's responsibility.

    Problems and errors

        Checking the target for supported ciphers may return that a cipher is
        not supported by the server  misleadingly.  Reason is most likely  an
        improper timeout for the connection. See  --timeout=SEC  option.

        If the specified targets accepts connections but does not speak  SSL,
        the connection will be closed after the system's TCP/IP-timeout. This
        script will hang (about 2-3 minutes).

        If reverse DNS lookup fails, an error message is returned as hostname,
        like:  '<<gethostbyaddr() failed>>'.
        Workaround to get rid of this message: use  --no-dns  option.

        All checks for EV are solely based on the information provided by the
        certificate.

        Some versions of openssl (< 1.x) may not support all required options
        which results in various error messages,  or  more worse,  may not be
        visibale at all. Available functionalitity of openssl will be checked
        for right at the beginning. Proper warnings and hints are printed.
        Following table shows the openssl option and how to disable it within
        o-saft.pl:
            #-------------------+---------------------
            * -nextprotoneg     | --no-nextprotoneg
            * -reconnect        | --no-reconnect
            * -tlsextdebug      | --no-tlsextdebug
            * -alpn             | --no-alpn
            #-------------------+---------------------

    Connection problems

        Sometimes the connection cannot be established. This may have various
        reasons.  Unfortunaly this script seems to hang then.  In  particular
        when checking for ciphers with  +cipher  command.  The reason is most
        likely that the server does not respond to the TCP/IP request,  hence
        the script closes the connection after the configured timeout (please
        see  --timeout=SEC  option).

        Continous connection attempts  can be inhibited with the  --ssl-error
        option, which is set by default. Avoiding further connections results
        in a loss of information and consequentely, leads to wrong checks.

        It is a trade-off to wait for all information done accurately,  or to
        get the results quickly. The logic to stop connecting for --ssl-error
        can be controlled with following additional options:
            #-----------------------+----------------------------------------
            * --ssl-error-max=CNT     | max. continous errors
            * --ssl-error-timeout=SEC | treat failure as error after timeout
            * --ssl-error-total=CNT   | max. amount of errors
            #-----------------------+----------------------------------------

        This means that no more connections are made when more than
            * --ssl-error-max errors occour sequentialy
        or
            * --ssl-error-total errors occoured

        Examples:
          * --ssl-error-max=3
          * --ssl-error-timeout=6
          * --ssl-error-total=6

        no more connections are made if for example  any sequence of timeouts
        occour:
              0 5 2 2                   - --ssl-error-max matches
              0 1 3 0 0 0 4 1 2 2 2     - --ssl-error-max matches
              0 5 0 2 0 2 2 0 2 0 2     - --ssl-error-total matches

        This allows to fine-tune the condition when to stop connecting to the
        target. For example, continous but not consecutive timeouts may indi-
        cate a bad or instable network connection, but not that the target to
        be connected blocks. In such a case sequence of timeouts like follows
        may be observed (assuming  --ssl-error-max=3):
              0 5 1 2 2 2 4 2 3 2 3 3 3 2
              . . . ^                 ^____ stop for  --ssl-error-timeout=3
              . . . |______________________ stop for  --ssl-error-timeout=2

        On normal (even slow) network connections  dozens of  connections per
        second are usual, hence the timeout is always  0 or 1.  Based on that
        experience  --ssl-error  is enabled and set with defaults as follows:
          * --ssl-error-max=5
          * --ssl-error-timeout=1
          * --ssl-error-total=10

    Poor systems

        Use of "openssl(1)"  is disabled by default on  Windows due to various
        performance problems. It needs to be enabled with  --openssl  option.

        On Windows the usage of  "openssl s_client" needs to be enabled using
        --s_client  option.

        On Windows it's a pain to specify a correct path for  --openssl=TOOL
        option. Variants are:
          * --openssl=/path/to/openssl.exe
          * --openssl=X:/path/to/openssl.exe
          * --openssl=\path\to\openssl.exe
          * --openssl=X:\path\to\openssl.exe
          * --openssl=\\path\\to\\openssl.exe
          * --openssl=X:\\path\\to\\openssl.exe

        You have to fiddle around to find the proper one.

    Debug and trace output



DEPENDENCIES

        All Perl modules and all  private moduels and files  will be searched
        for using paths  available in the  '@INC'  variable.  '@INC'  will be
        prepended by following paths:

          * .
          * ./lib
          * INSTALL_PATH
          * INSTALL_PATH/lib

        Where  'INSTALL_PATH'  is the path where the tool is installed.
        To see which files have been included use:
              o-saft.pl +version --v --user

    Perl modules

        * "IO::Socket::SSL(3pm)"
        * "IO::Socket::INET(3pm)"
        * "Net::SSLeay(3pm)"
        * lib/SSLinfo
        * lib/SSLhello

        Perl modules loaded and used for some options only:

        * Net::DNS(3pm)
        * Time::Local(3pm)

    Additional files used if requested

        * .o-saft.pl
        * o-saft-docker
        * o-saft-README
        * lib/OTrace.pm
        * lib/OMan.pm
        * lib/OUsr.pm


INSTALLATION

        The tool can be installed in any path. It just requres the modules as
        described in  DEPENDENCIES  above. However, it's recommended that the
        modules  SSLhello  and  SSLinfo  are found  in the directory  './lib'
        where  'o-saft.pl'  is installed.

        For security reasons, most modern libraries  disabled or even removed
        insecure or "dirty" functionality.  As the purpose of this tool is to
        detect such insecure settings, functions, etc.,  it needs these dirty
        things enabled. It needs (incomplete list):

          * insecure protocols like SSLv2, SSLv3,
          * more ciphers enabled, like NULL-MD5, AECDH-NULL-SHA, etc.,
          * some SSL extensions and options.

        Therefore we recommend to compile and install at least following:

          * OpenSSL  with SSLv2, SSLv3 and more ciphers enabled,
          * Net::SSLeay  compiled with openssl version as described before.

        Please read the  SECURITY  section first before following the install
        instructions below.

    Quickstart

        The script  INSTALL.sh  provides a quick method to check, compile and
        install anything needed. Please see:

          INSTALL.sh --help

        For more details, read on ...

    Requirements for OpenSSL

        To build openssl following packages are requred  (note that the names
        may differ depending on the used platform):
          * libidn11-dev

          * libidn2-0-dev
          * libgmp-dev
          * libzip-dev
          * libsctp-dev
          * libkrb5-dev

        Also, following Perl modules should be installed:
          * Module::Build
          * Net::LibIDN
          * Net::LibIDN2
          * Mozilla::CA

    OpenSSL

        Currently (since 18.06.18) it is recommend to build openssl using:
              usr/install_openssl.sh

        Other possibilities are:
          * compiling openssl using following sources
            https://github.com/PeterMosmans/openssl/
            see  Example: Compile openssl,
          * use any of the precomiled versions provided by https://testssl.sh/
          * use Docker owasp/o-saft (which contains a special openssl)

        The sources are available at
          * https://github.com/PeterMosmans/openssl/archive/1.0.2-chacha.zip
        A precomiled static versions are available at
          * https://github.com/drwetter/testssl.sh/ (see bin directory there)

        For all following installation examples we assume:
          * openssl-1.0.2-chacha.zip or openssl-1.0.2d.tar.gz
          * /usr/local as base installation directory
          * a bourne shell (sh) compatible shell

    Example: Precompiled OpenSSL

        Simply download the tarball or zip file for your platform, unpack it,
        and install (copy) the binaries into a directory of your choice.

        Note that  Net::SSLeay  needs to be adapted properly then.

    Example: Compile openssl

        OpenSSL can be used from http://openssl.org/ or, as recommended, from
        https://github.com/PeterMosmans/openssl/ .

        OpenSSL-chacha
        Compiling and installing the later is as simple as:

              unzip openssl-1.0.2-chacha.zip
              cd openssl-1.0.2-chacha
              ./config --shared -Wl,-rpath=/usr/local/lib
              make
              make test
              make install

        which will install openssl, libssl.so, libcrypto.so  and some include
        files as well as the include files in  /usr/local/ .
        The shared version of the libraries are necessary for  Net::SSLeay.

        For a more complete build, plese see:  usr/install_openssl.sh .

        OpenSSL.org
        Building openssl from the offical  openssl.org  sources requires some
        patching before compiling and installing the libraries and binaries.

        Example with openssl-1.0.2d:

              echo == unpack tarball
              tar xf openssl-1.0.2d.tar.gz
              cd openssl-1.0.2d

              echo == backup files to be modified
              cp ssl/s2_lib.c{,.bak}
              cp ssl/s3_lib.c{,.bak}
              cp ssl/ssl3.h{,.bak}
              cp ssl/tls1.h{,.bak}

              echo == patch files
              vi ssl/tls1.h         +/TLS1_ALLOW_EXPERIMENTAL_CIPHERSUITES/
                  # define TLS1_ALLOW_EXPERIMENTAL_CIPHERSUITES  1
              vi ssl/ssl3.h ssl/s{2,3}_lib.c   +"/# *if 0/"
                  #==> remove all   # if 0  and corresponding  #endif
                  #    except if lines contain:
                  #        _FZA
                  #        /* Fortezza ciphersuite from SSL 3.0
                  #        /* Do not set the compare functions,
                  #        if (s->shutdown & SSL_SEND_SHUTDOWN)

              echo == configure with static libraries
              echo omitt the zlib options if zlib-1g-dev is not installed
              echo omitt the krb5 options if no kerberos libraries available
              LD_RUN_PATH=/usr/local/openssl/lib
              LDFLAGS="-rpath=$LD_RUN_PATH" && export LDFLAGS
              ./config --prefix=/usr/local --openssldir=/usr/local/ssl \
                  enable-zlib zlib zlib-dynamic enable-ssl2 \
                  enable-krb5 --with-krb5-flavor=MIT \
                  enable-mdc2 enable-md2 enable-rc5  enable-rc2 \
                  enable-cms  enable-ec  enable-ec2m enable-ecdh enable-ecdsa \
                  enable-gost enable-seed enable-idea enable-camellia \
                  enable-rfc3779 enable-ec_nistp_64_gcc_128 \
                  experimental-jpake -fPIC \
                  -DTEMP_GOST_TLS -DTLS1_ALLOW_EXPERIMENTAL_CIPHERSUITES \
                  -shared

              echo == make binaries and libraries
              make depend
              make
              make test
              make install

              echo == if you want static binaries and libraries
              make clean
              echo same ./config as before but without shared option
              ./config --prefix=/usr/local --openssldir=/usr/local/ssl \
                  enable-zlib zlib zlib-dynamic enable-ssl2 \
                  enable-krb5 --with-krb5-flavor=MIT \
                  enable-mdc2 enable-md2 enable-rc5  enable-rc2 \
                  enable-cms  enable-ec  enable-ec2m enable-ecdh enable-ecdsa \
                  enable-gost enable-seed enable-idea enable-camellia \
                  enable-rfc3779 enable-ec_nistp_64_gcc_128 \
                  experimental-jpake -fPIC  -static \
                  -DTEMP_GOST_TLS -DTLS1_ALLOW_EXPERIMENTAL_CIPHERSUITES
              make depend
              make
              make test
              echo next make will overwrite the previously installed dynamic
              echo shared openssl binary with the static openssl binary
              make install

    Example: Compile Net::SSLeay

        To enable support for ancient protocol versions,  Net::SSLeay must be
        compiled manually after patching 'SSLeay.xs' (see below).
        Reason is, that  Net::SSLeay  enables some functionality for  SSL/TLS
        according the identified openssl version. There is, currently (2015),
        no possibility to enable this functionality  by passing options on to
        the configuration script 'perl Makefile.PL'.

        Building our own library and module (with openssl from '/usr/local'):

              echo == unpack tarball
              tar xf Net-SSLeay-1.72.tar.gz
              cd Net-SSLeay-1.72

              echo == patch files
              echo "edit SSLeay.xs and change some #if as described below"
              LD_RUN_PATH=/usr/local/openssl/lib
              LDFLAGS="-rpath=$LD_RUN_PATH" && export LDFLAGS
              env OPENSSL_PREFIX=/usr/local perl Makefile.PL PREFIX=/usr/local \
                  INC=-I/usr/local/include  DEFINE=-DOPENSSL_BUILD_UNSAFE=1
              make
              make install
              cd /tmp && o-saft.pl +version

        SSLeay.xs needs to be changed as follows:
          * search for
              #ifndef OPENSSL_NO_SSL2
              #if OPENSSL_VERSION_NUMBER < 0x10000000L

              const SSL_METHOD *
              SSLv2_method()

              #endif
              #endif

              #ifndef OPENSSL_NO_SSL3
              #if OPENSSL_VERSION_NUMBER < 0x10002000L

              const SSL_METHOD *
              SSLv3_method()

              #endif
              #endif

          * and replace by
              const SSL_METHOD *
              SSLv2_method()

              const SSL_METHOD *
              SSLv3_method()

        Note that  Net::SSLeay  will be installed in '/usr/local/' then. This
        can be adapted to your needs by passing another path to the  'PREFIX'
        and  'DESTDIR'  parameter.

        Following command can be used to check  which methods are avilable in
        Net::SSLeay, hence above patches can be verified:

              perl -MSSLinfo -le 'print SSLinfo::ssleay_test();'

    Testing openssl

        After installation as descibed above finished, openssl may be tested:

              echo already installed openssl (found with PATH environment)
              openssl ciphers -v
              openssl ciphers -V -ssl2
              openssl ciphers -V -ssl3
              openssl ciphers -V ALL
              openssl ciphers -V ALL:COMPLEMENTOFALL
              openssl ciphers -V ALL:eNULL:EXP

              echo own compiled and installed openssl
              /usr/local/openssl ciphers -v
              /usr/local/openssl ciphers -V -ssl2
              /usr/local/openssl ciphers -V -ssl3
              /usr/local/openssl ciphers -V ALL
              /usr/local/openssl ciphers -V ALL:COMPLEMENTOFALL
              /usr/local/openssl ciphers -V ALL:eNULL:EXP

        The difference should be obvious.
        Note, the commands using  'ALL:COMPLEMENTOFALL'  and  'ALL:eNULL:EXP'
        should return the same result.

    Testing Net::SSLeay

        As we want to test the separately installed  Net::SSLeay,  it is best
        to do it with  o-saft.pl  itself:

              o-saft.pl +version

        we should see a line similar to follwong at the end of the output:
              Net::SSLeay   1.72  /usr/local/lib/x86_64-linux-gnu/perl/5.20.2/Net/SSLeay.pm

        Now check for supported (known) ciphers:

              o-saft.pl ciphers -V

        we should see lines similar to those of the last '/usr/local/openssl'
        call. However, it should contain more cipher lines.

    Stand-alone executable

        Some people asked for a stand-alone executable (mainly for Windows).
        Even Perl is a scripting language there are situations where a stand-
        alone executable would be nice, for example if the installed perl and
        its libraries are outdated, or if perl is missing at all.

        Currently (2016) there are following possibilities to generate such a
        stand-alone executable:

          * perl with PAR::Packer module
              pp -C -c o-saft.pl
              pp -C -c o-saft.pl -M Net::DNS -M Net::SSLeay -M IO::Socket \
                  -M SSLinfo -M SSLhello -M OCfg
              pp -C -c checkAllCiphers.pl
              pp -C -c checkAllCiphers.pl -M Net::DNS

          * ActiveState perl with its perlapp
              perlapp --clean o-saft.pl
              perlapp --clean o-saft.pl -M Net::DNS -M Net::SSLeay -M IO::Socket \
                  -M SSLinfo -M SSLhello -M OCfg
              perlapp --clean checkAllCiphers.pl
              perlapp --clean checkAllCiphers.pl -M Net::DNS -M OCfg

          * perl2exe from IndigoSTar
              perl2exe o-saft.pl
              perl2exe checkAllCiphers.pl

        For details  on building the executable,  for example  how to include
        all required modules, please refer to the documentation of the tool.
           * http://search.cpan.org/~rschupp/PAR-Packer-1.030/lib/PAR/Packer.pm
           * http://docs.activestate.com/pdk/6.0/PerlApp.html
           * http://www.indigostar.com

        Note that  pre-build executables (build by perlapp, perl2exe)  cannot
        be provided due to licence problems.
        Also note that using  stand-alone executable have not been tested the
        same way as the  o-saft.pl  itself. Use them at your own risk.


ABOUT CGI

        This script can be used as CGI application.  Output is the same as in
        common CLI mode. The output will be prefixed with the HTTP header
        'Content-Type:text/plain'.
        The script  "o-saft.cgi"  should be used as wrapper for "o-saft.pl" .
        The HTML form  "o-saft.cgi.html"  which can be generated with:

              o-saft.pl --help=gen-cgi

        should be used as front-end for  "o-saft.cgi".

    CGI-form functionality

        This form provides following functionality:

        * top menu bar with following menus:
          ** ☰          - general informations about CGI usage
          ** Cmd        - quick commands menu
          ** Opt        - quick options menu
          ** Help       - various help pages

        * input field "Host[:Port]" for a target (hostname or URL)

        * GUI sections
          ** Simple GUI - simple form with most common commands and options
                          Each provided +command buttons submit the form with
                          the selected options and the clicked command.

          ** Full GUI Commands & Options - form with all commands and options
                          Its content is the same as in sections  COMMANDS  
                          and  OPTIONS  of the complete help page (see --help
                          option or "☰ -> ? Help" in top menu bar).

        In both GUI sections following buttons exist:

        * ^             - return to top of form
        * start         - submit form with selected command and options

        In general, command buttons which submit the form are yellow. Buttons
        which show some help, mainly in a new browser tab, are grey.

    CGI-form limitations

        * The generated form provides commands and options which are rejected
          by  o-saft.cgi  (see below).

        * The generated form may contain references (links) to sections which
          are not part of the form.

        * Only one target can be provided,  however, it is obvious how to use
          more targets ...

        * The  --html4  or  --html5  option should be used together  with the
          --header  option, otherwise the generated HTML may be corrupted for
          some commands.

    CGI script limitations

        The script returns an empty page (HTML body) for following reasons:

        * Use of local or multicast IPs as target.

        * Use of dangerous commands or options.

        For deatils please see

              o-saft.pl --help=ABOUT
              perldoc o-saft.cgi


DOCKER

        The tool can be used inside a Docker image. To start  o-saft.pl  inside
        the Docker image, use following:

              o-saft-docker +info some.tld
        or
              docker run --rm -it owasp/o-saft +info some.tld

        For more details, please refer to:

              o-saft-docker usage
              o-saft-docker -help


BUILD DOCKER IMAGE

        The Docker image can be installed as follows:

              docker pull owasp/o-saft

        The image can also easily be build from the Dockerfile (which is part
        of the distribution) as follows:

              o-saft-docker build

        To build the image from the Dockerfile with docker commands, see:

              o-saft-docker -n build

        For more details, please refer to:

              o-saft-docker -help


SEE ALSO

        * "openssl(1)", "Net::SSLeay(3pm)", lib/SSLhello, lib/SSLinfo, "timeout(1)"
        * http://www.openssl.org/docs/apps/ciphers.html
        * "IO::Socket::SSL(3pm)", "IO::Socket::INET(3pm)"
        * o-saft, o-saft-docker, o-saft-docker-dev, Dockerfile, docker


HACKER's INFO

    Note on SSL versions

        Automatically detecting the supported SSL versions of the underlaying
        system is a hard job and not always possible. Reasons could be:

        * used Perl modules (Socket::SSL, Net::SSLeay) does not handle errors
          properly. Erros may be:
              invalid SSL_version specified at ... IO/Socket/SSL.pm
              Use of uninitialized value in subroutine entry at lib/IO/Socket/SSL.pm

          There're some workarounds implemented since version 15.11.15 .

        * the underlaying libssl does not support the version, which then may
          result in segmentation fault

        * the underlaying libssl is newer than the Perl module and the module
          has not been reinstalled. This most often happens with  Net::SSLeay
          This can be detected with (see version numbers for Net::SSLeay):
              o-saft.pl +version

        * perl (in particular a used module, see above)  may bail out  with a
          compile error, like
              Can't locate auto/Net/SSLeay/CTX_v2_new.al in @INC ...

          There're some workarounds implemented since version 15.11.15 .

        We try to detect unsupported versions and disable them automatically,
        a warning like follwoing is shown then:
              **WARNING: 303: SSL version 'SSLv2': not supported by openssl

        All such warnings look like:
              **WARNING: 303: SSL version 'SSLv2': ...

        If problems occour with  SSL versions, following commands and options
        may help to get closer to the reason or can be used as workaround:
              o-saft.pl +version
              o-saft.pl +version --v
              o-saft.pl +version | grep versions
              o-saft.pl +version | grep 0x
              o-saft.pl +protocols your.tld
              o-saft.pl +protocols your.tld --no-rc

        Checking for SSL version is done at one place in the code, search for
              supported SSL versions

        However, there are some dirty hacks where  SSLv2 and SSLv3 is checked
        again.

    Manipulating Perl's @INC

        Most perl executables use a compiled-in  list of directories where to
        find its modules. This list is available in Perl's @INC variable.

        There are various ways to add more directories to @INC  but no simple
        method to remove directories from it.

        The option  --no-inc=PATTERN  can be used to  remove directories from
        @INC. Note that PATTERN is a RegEx and will remove all matching paths
        from @INC. Example:

          remove all directories starting with "/usr/local/":
              o-saft.pl --no-inc=^/usr/local/ ...

          remove all directories containing "/local/":
              o-saft.pl --no-inc=/local/ ...

          just remove "/usr/local/lib/site_perl"
              o-saft.pl --no-inc=^/usr/local/lib/site_perl$ ...

        For convenience the option  --inc=PATH  exists and adds the specified
        path to @INC (same as using "perl -IPATH ...".

        The patterns given with  --no-inc=  are removed from @INC  late, when
        all default directories and those passed with  --inc=  were added.

    Using private libssl.so and libcrypt.so

        For all  cryptographic functionality  the libraries  installed on the
        system will be used. In particular Perl's "Net::SSLeay(3pm)" module, the
        system's  libssl.so and libcrypt.so  and the "openssl(1)"  executable.

        It is possible to provide your own libraries, if the  Perl module and
        the executable are  linked using dynamic shared objects (a.k.a shared
        library, position independent code).
        The appropriate option is  --lib=PATH.

        On most systems these libraries are loaded at startup of the program.
        The runtime loader uses a preconfigured list of directories  where to
        find these libraries. Also most systems provide a special environment
        variable to specify  additional paths  to directories where to search
        for libraries, for example the  LD_LIBRARY_PATH environment variable.
        This is the default environment variable used herein.  If your system
        uses  another name it must be specified with the  --envlibvar=NAME
        option, where  NAME  is the name of the environment variable.

    Understanding  --exe=PATH, --lib=PATH, --openssl=TOOL

        If any of  --exe=PATH  or  --lib=PATH  is provided, the pragram calls
        ('exec') itself recursively with all given options, except the option
        itself. The environment variables  'LD_LIBRARY_PATH'  and 'PATH'  are
        set before executing as follows:
          * prepend  'PATH'  with all values given by  --exe=PATH
          * prepend  'LD_LIBRARY_PATH'  with all values given by  --lib=PATH


        This is exactly, what Cumbersome approach below describes. So these
        option simply provide a shortcut for that.

        Note that  --openssl=TOOL  is a full path to the  openssl  executable
        and will not be changed.  However, if it is a relative path, it might
        be searched for using the previously set  'PATH'  (see above).

        Note that  'LD_LIBRARY_PATH'  is the default.  It can be changed with
        the  --envlibvar=NAME  option.

        While  --exe  mainly impacts the "openssl(1)" executable,  --lib  also
        impacts o-saft.pl itself, as it loads other shared libraries if found.

        Bear in mind that  all these options  can affect the behaviour of the
        openssl subsystem,  influencing both  which executable is called  and
        which shared libraries will be used.

        Note that no checks are done if the options are set proper. To verify
        the settings, following commands may be used:
          o-saft.pl --lib=YOUR-PATH --exe=YOUR-EXE +version
          o-saft.pl --lib=YOUR-PATH --exe=YOUR-EXE --v +version
          o-saft.pl --lib=YOUR-PATH --exe=YOUR-EXE --v --v +version

        Why so many options?  Exactly as described above, these options allow
        the users to tune the behaviour of the tool to their needs.  A common
        use case is to enable the use of a separate openssl build independent
        of the OpenSSL package used by the operating system.  This allows the
        user fine grained control over OpenSSL's encryption suites  which are
        compiled/available, without affecting the core system.

    Caveats

        Depending on your system and the used modules and executables, it can
        be tricky to replace the configured shared libraries with own ones.
        Reasons are:
          a) the linked library name contains a version number,
          b) the linked library uses a fixed path,
          c) the linked library is searched at a predefined path,
          d) the executable checks the library version when loaded.

        Only the first one a) can be circumvented.  The last one d) can often
        be ignored as it only prints a warning or error message.

        To circumvent the "name with version number" problem try following:

        1) use "ldd(1)"  (or a similar tool) to get the names used by openssl:

              ldd /usr/bin/openssl

        which returns something like:

              libssl.so.0.9.8 => /lib/libssl.so.0.9.8 (0x00007f940cb6d000)
              libcrypto.so.0.9.8 => /lib/libcrypto.so.0.9.8 (0x00007f940c7de000)
              libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f940c5d9000)
              libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007f940c3c1000)
              libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f940c02c000)
              /lib64/ld-linux-x86-64.so.2 (0x00007f940cdea000)

        Here only the first two libraries are important.  Both,  libcrypto.so
        and libssl.so  need to be version "0.9.8" (in this example).

        2) create a directory for your libraries, for example:

              mkdir /tmp/dada

        3) place your libraries there, assuming they are:

              /tmp/dada/libssl.so.1.42
              /tmp/dada/libcrypto.so.1.42

        4) create symbolic links in that directory:

              ln -s libssl.so.1.42    libssl.so.0.9.8
              ln -s libcrypto.so.1.42 libcrypto.so.0.9.8

        5) test program with following option:

              o-saft.pl +libversion --lib=/tmp/dada
              o-saft.pl +list --v   --lib=/tmp/dada

          or:

              o-saft.pl +libversion --lib=/tmp/dada -exe=/path/to-openssl
              o-saft.pl +list --v   --lib=/tmp/dada -exe=/path/to-openssl

        6) start program with your options, for example:

              o-saft.pl --lib=/tmp/dada +ciphers

        This works if "openssl(1)"  uses the same shared libraries as
       "Net::SSLeay(3pm)",  which most likely is the case.

        It's tested with Unix/Linux only. It may work on other platforms also
        if they support such an environment variable and the installed
       "Net::SSLeay(3pm)"  and "openssl(1)"  are linked using dynamic shared
        objects.

        Depending on  compile time settings  and/or  the location of the used
        tool or lib, a warning like following may occur:

              WARNING: can't open config file: /path/to/openssl/ssl/openssl.cnf

        This warning can be ignored, usually as  req  or  ca  sub commands of
        openssl is not used here.
        To fix the problem, either use  --openssl-cnf=FILE  option or set the
        the environment variable OPENSSL_CONF properly.

      Cumbersome approach

        A more cumbersome approach to call  this program is to set  following
        environment variables in your shell:

              PATH=/tmp/dada-1.42/apps:$PATH
              LD_LIBRARY_PATH=/tmp/dada-1.42

      Windows caveats

        I.g. the used libraries on Windows are libeay32.dll and ssleay32.dll.

        Windows also supports the LD_LIBRARY_PATH environment variable. If it
        does not work as expected with that variable, it might be possible to
        place the libs in the same directory as the  corresponding executable
        (which is found by the PATH environment variable).

    Using CGI mode

        This script can be used as  CGI application. Output is the same as in
        common CLI mode, using  'Content-Type:text/plain'.  Keep in mind that
        the used modules like "Net::SSLeay(3pm)" will write some debug messages
        on  STDERR instead  STDOUT.  Therefore multiple  --v  and/or  --trace
        options behave slightly different.

        No additional external files like  RC-FILE or DEBUG-FILE  are read in
        CGI mode; they are silently ignored.
        Some options are disabled in CGI mode  because they are dangerous  or
        don't make any sense.

      WARNING

          There are  no  input data validation checks implemented herein. All
          input data is url-decoded once and then used verbatim.
          More advanced checks must be done outside before calling this tool.
          Please see  o-saft.cgi  .

        It is not recommended to run this tool in CGI mode.
        You have been warned!


    Using user specified code

        There are some functions called within the program flow, which can be
        filled with any Perl code.  Empty stubs of the functions are prepared
        in  lib/OUsr.pm.  See also  USER-FILE .


DEBUG

        For debugging, tracing or using outdated modules, please see:

              o-saft.pl --help=development


TESTING

        What is "testing"?
        This tool itself is for testing something (TLS etc.),  so it needs to
        be explained what testing here is about.  Following testing types are
        distinguished:

        * User testing
        * Functional testing
        * Developer (internal) testing
        * Testing results

        All descriptions intended for development and can be found with:

              o-saft.pl --help=development

    User testing

        During normal use of the tool, "testing" is only required for hunting
        problems with the connected target. Following options for tracing and
        verbosity can be used for that:

      --v

          Print more information about checks.

      --trace

          Print debugging messages.
          For more details, please see  Options for tracing and debugging .

    Functional testing
    Developer (internal) testing
    Testing results

        Please see:  'o-saft.pl --help=development'


EXAMPLES

        (o-saft.pl in all following examples is the name of the tool)

    General

          o-saft.pl +cipher some.tld
          o-saft.pl +info   some.tld
          o-saft.pl +check  some.tld
          o-saft.pl +quick  some.tld
          o-saft.pl +help=commands
          o-saft.pl +certificate  some.tld
          o-saft.pl +fingerprint  some.tld 444
          o-saft.pl +after +dates some.tld
          o-saft.pl +version
          o-saft.pl +version --v
          o-saft.pl +list
          o-saft.pl +list    --v

    Some specials

        * Get an idea how messages look like
          o-saft.pl +check --cipher=RC4 some.tld

        * Check for Server Name Indication (SNI) usage only
          o-saft.pl +sni some.tld

        * Check for SNI and print certificate's subject and altname
          o-saft.pl +sni +cn +altname some.tld

        * Check for all SNI, certificate's subject and altname issues
          o-saft.pl +sni_check some.tld

        * Only print supported ciphers
          o-saft.pl +cipher --enabled some.tld

        * Only print unsupported ciphers
          o-saft.pl +cipher --disabled some.tld

        * Test for a specific ciphers
          o-saft.pl +cipher --cipher=ADH-AES256-SHA some.tld

        * Test for DTLS ciphers only
          o-saft.pl +cipher --no-tls

        * Test for SSL/TLS ciphers only
          o-saft.pl +cipher --no-dtls

        * Test for TLSv1.3 ciphers only
          o-saft.pl +cipher --no-tls --no-dtls --tlsv13

        * Consequently following tests no ciphers at all
          o-saft.pl +cipher --no-tls --no-dtls

        * Test using a private libssl.so, libcrypto.so and openssl
          o-saft.pl +cipher --lib=/foo/bar-1.42 --exe=/foo/bar-1.42/apps some.tld

        * Test using a private openssl
          o-saft.pl +cipher --openssl=/foo/bar-1.42/openssl some.tld

        * Test using a private openssl also for testing supported ciphers
          o-saft.pl +cipher --openssl=/foo/bar-1.42/openssl --force-openssl some.tld

        * Show supported (enabled) ciphers with their DH parameters:
          o-saft.pl +cipher-dh --ciphermode=openssl example.tld

        * Check for all known ciphers (simple internal test function):
          checkAllCiphers.pl example.tld
          checkAllCiphers.pl example.tld --range=full --v


        * Use your private texts in output
          o-saft.pl +check some.tld --cfg-text=desc="my special description"

        * Use your private texts from rc-file
          o-saft.pl --help=cfg-text >> .o-saft.pl
            edit as needed: .o-saft.pl
          o-saft.pl +check some.tld

        * Use your private hint texts in output
          o-saft.pl +check some.tld --cfg-hint=renegotiation="my special hint text"

        * Get the certificate's Common Name for a bunch of servers:
          o-saft.pl +cn example.tld some.tld other.tld
          o-saft.pl +cn example.tld some.tld other.tld --showhost --no-header

        * Generate simple parsable output
          o-saft.pl --legacy=quick --no-header +info  some.tld
          o-saft.pl --legacy=quick --no-header +check some.tld
          o-saft.pl --legacy=quick --no-header --trace-key +info  some.tld
          o-saft.pl --legacy=quick --no-header --trace-key +check some.tld

        * Generate simple parsable output for multiple hosts
          o-saft.pl --legacy=quick --no-header --trace-key --showhost +check some.tld other.tld

        * Just for curiosity
          o-saft.pl some.tld +fingerprint --format=raw
          o-saft.pl some.tld +certificate --format=raw | openssl x509 -noout -fingerprint

    Testing with exit code

        * Test SSL/TLS connection and return exit code
          o-saft.pl +check  --exitcode  some.tld

        * Test ciphers and return exit code with details about exit code
          o-saft.pl +cipher --exitcode --exitcode-v  some.tld

        * Test ciphers and return exit code for ciphers only
          o-saft.pl +cipher --exitcode --exitcode-no-prot  some.tld

        * Test with exit code but avoid checks considered 'yes' even if 'no'
          o-saft.pl +check  --exitcode --ignore-out=ev- --ignore-out=rfc_7525 some.tld

    Specials for hunting problems with connections etc.

        * Do not read rc-file .o-saft.pl
          o-saft.pl +info some.tld --no-rc

        * Show command-line argument processing
          o-saft.pl +info some.tld --trace-arg

        * Simple tracing
          o-saft.pl +cn   some.tld --trace
          o-saft.pl +info some.tld --trace

        * A bit more tracing
          o-saft.pl +cn   some.tld --trace --trace

        * Show internal variable names in output
          o-saft.pl +info some.tld --trace-key

        * Show internal argument processeing
          o-saft.pl +info --trace-arg some.tld

        * Show internal control flow
          o-saft.pl +info some.tld --v
          o-saft.pl +info some.tld --trace-me

        * Show internal timing
          o-saft.pl +info some.tld --trace-time

        * Show checking ciphers
          o-saft.pl +cipher some.tld --v

        * Show checking ciphers
          o-saft.pl +cipher some.tld --v --v --ciphermode=openssl

        * Show values retrieved from target certificate directly
          o-saft.pl +info some.tld --no-cert --no-cert --no-cert-text=Value-from-Certificate

        * Show certificate CA verifications
          o-saft.pl some.tld +chain_verify +verify +error_verify +chain

        * Avoid most performance and timeout problems (don't use  --v --trace)
          o-saft.pl +info some.tld --no-dns --no-sni --ignore-no-conn
          o-saft.pl +info some.tld --no-dns --no-sni --no-cert --no-http --no-openssl

        * Identify timeout problems
          o-saft.pl +info some.tld --v --trace-time

          this will show lines containing:
          #O-Saft  CMD: test ...




DOCUMENTATION

        For a description how documentation is organised, please see:

          perldoc o-saft.pl

        The documentation here focuses on user part only.

    User documentation

        The complete user documentation (or "help") is provided with:

          o-saft.pl --help

        But it may be difficult to find the proper information there.  To get
        more selective documentations, the  --help=*  options can be used. To
        get an overview which  --help=*  options are available, use:

          o-saft.pl --help=HELP

        It can be used to get well known parts of the documentation specified
        by the keyword, ('HELP' in example above).
        To find any text with some lines of context, following could be used:

          o-saft.pl --help | egrep -i -C 3 "some text"

        This is simply avaiable with the wrapper tool "o-saft":

          o-saft --help="some text"

        In the GUI a more sophisticate search is implemented, see the  "Help"
        window there:

          o-saft.tcl 

        All files used for documentation, wether source files, or contributed
        files, or generated files, are located in the  doc/  directory.

    Developer documentation

        To get used to documentation for developers, best start reading:

          doc/concepts.txt
          perldoc t/Makefile.pod


ATTRIBUTION

        Based on ideas (in alphabetical order) of:

        * cnark.pl, SSLAudit.pl sslscan, ssltest.pl, sslyze.py, testssl.sh

        * O-Saft - OWASP SSL advanced forensic tool
            Thanks to Gregor Kuznik for this title.

        * Basic cipher check and some proxy functionality implemented by Torsten Gigler.

        * For re-writing some docs in proper English, thanks to Robb Watson.

        * Code to check heartbleed vulnerability adapted from
            Steffen Ullrich (08. April 2014):
            https://github.com/noxxi/p5-scripts/blob/master/check-ssl-heartbleed.pl

        * Colouration inspired by https://testssl.sh/ .


VERSION

        @(#) 24.06.24

AUTHOR

        31. July 2012 Achim Hoffmann

        Project Home: https://owasp.org/www-project-o-saft/

