fizz::PlaintextReadRecordLayer Class Reference

#include <PlaintextRecordLayer.h>

Inheritance diagram for fizz::PlaintextReadRecordLayer:

Public Member Functions
	~PlaintextReadRecordLayer () override=default
virtual void	setSkipEncryptedRecords (bool enabled)
folly::Optional< TLSMessage >	read (folly::IOBufQueue &buf) override
folly::Optional< ProtocolVersion >	getReceivedRecordVersion () const
EncryptionLevel	getEncryptionLevel () const override
Public Member Functions inherited from fizz::ReadRecordLayer
virtual	~ReadRecordLayer ()=default
virtual folly::Optional< Param >	readEvent (folly::IOBufQueue &socketBuf)
virtual bool	hasUnparsedHandshakeData () const

Private Attributes
bool	skipEncryptedRecords_ {false}
folly::Optional< ProtocolVersion >	receivedRecordVersion_

Additional Inherited Members
Static Public Member Functions inherited from fizz::ReadRecordLayer
static folly::Optional< Param >	decodeHandshakeMessage (folly::IOBufQueue &buf)

Detailed Description

Definition at line 15 of file PlaintextRecordLayer.h.

Constructor & Destructor Documentation

fizz::PlaintextReadRecordLayer::~PlaintextReadRecordLayer ( )

overridedefault

Member Function Documentation

EncryptionLevel fizz::PlaintextReadRecordLayer::getEncryptionLevel ( ) const

overridevirtual

Returns the current encryption level of the data that the read record layer can process.

Implements fizz::ReadRecordLayer.

Definition at line 97 of file PlaintextRecordLayer.cpp.

References fizz::Plaintext.

Referenced by getReceivedRecordVersion().

                                                                   {
  return EncryptionLevel::Plaintext;
}

folly::Optional<ProtocolVersion> fizz::PlaintextReadRecordLayer::getReceivedRecordVersion ( ) const

inline

Get the record protocol version of the most recent received record. Should only be used for logging.

Definition at line 32 of file PlaintextRecordLayer.h.

References getEncryptionLevel(), and receivedRecordVersion_.

                                                                  {
    return receivedRecordVersion_;
  }

folly::Optional< TLSMessage > fizz::PlaintextReadRecordLayer::read ( folly::IOBufQueue &  buf )

overridevirtual

Reads a fragment from the record layer. Returns an empty optional if insuficient data available. Throws if data malformed. On success, advances buf the amount read.

Implements fizz::ReadRecordLayer.

Definition at line 23 of file PlaintextRecordLayer.cpp.

References fizz::alert, fizz::application_data, folly::IOBufQueue::chainLength(), fizz::change_cipher_spec, folly::IOBufQueue::empty(), fizz::TLSMessage::fragment, folly::IOBufQueue::front(), fizz::handshake, folly::hexlify(), fizz::illegal_parameter, folly::gen::move, folly::none, receivedRecordVersion_, skipEncryptedRecords_, folly::IOBufQueue::splitAtMost(), folly::IOBufQueue::trimStart(), fizz::TLSMessage::type, and uint16_t.

Referenced by setSkipEncryptedRecords().

                          {
  while (true) {
    folly::io::Cursor cursor(buf.front());

    if (buf.empty() || !cursor.canAdvance(kPlaintextHeaderSize)) {
      return folly::none;
    }

    TLSMessage msg;
    msg.type = static_cast<ContentType>(cursor.readBE<ContentTypeType>());

    if (skipEncryptedRecords_) {
      if (msg.type == ContentType::application_data) {
        cursor.skip(sizeof(ProtocolVersion));
        auto length = cursor.readBE<uint16_t>();
        if (buf.chainLength() < (cursor - buf.front()) + length) {
          return folly::none;
        }
        length +=
            sizeof(ContentType) + sizeof(ProtocolVersion) + sizeof(uint16_t);
        buf.trimStart(length);
        continue;
      } else if (msg.type != ContentType::change_cipher_spec) {
        skipEncryptedRecords_ = false;
      }
    }

    switch (msg.type) {
      case ContentType::handshake:
      case ContentType::alert:
        break;
      case ContentType::change_cipher_spec:
        break;
      default:
        throw std::runtime_error(folly::to<std::string>(
            "received plaintext content type ",
            static_cast<ContentTypeType>(msg.type),
            ", header: ",
            folly::hexlify(buf.splitAtMost(10)->coalesce())));
    }

    receivedRecordVersion_ =
        static_cast<ProtocolVersion>(cursor.readBE<ProtocolVersionType>());

    auto length = cursor.readBE<uint16_t>();
    if (length > kMaxPlaintextRecordSize) {
      throw std::runtime_error("received too long plaintext record");
    }
    if (length == 0) {
      throw std::runtime_error("received empty plaintext record");
    }
    if (buf.chainLength() < (cursor - buf.front()) + length) {
      return folly::none;
    }

    cursor.clone(msg.fragment, length);

    buf.trimStart(cursor - buf.front());

    if (msg.type == ContentType::change_cipher_spec) {
      msg.fragment->coalesce();
      if (msg.fragment->length() == 1 && *msg.fragment->data() == 0x01) {
        continue;
      } else {
        throw FizzException(
            "received ccs", AlertDescription::illegal_parameter);
      }
    }

    return std::move(msg);
  }
}

virtual void fizz::PlaintextReadRecordLayer::setSkipEncryptedRecords ( bool  enabled )

inlinevirtual

Skip over received encrypted records until a plaintext record is received.

Definition at line 22 of file PlaintextRecordLayer.h.

References read(), and skipEncryptedRecords_.

                                                     {
    skipEncryptedRecords_ = enabled;
  }

Member Data Documentation

folly::Optional<ProtocolVersion> fizz::PlaintextReadRecordLayer::receivedRecordVersion_

private

Definition at line 41 of file PlaintextRecordLayer.h.

Referenced by getReceivedRecordVersion(), and read().

bool fizz::PlaintextReadRecordLayer::skipEncryptedRecords_ {false}

private

Definition at line 39 of file PlaintextRecordLayer.h.

Referenced by read(), and setSkipEncryptedRecords().

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The documentation for this class was generated from the following files:

• proxygen/fizz/fizz/record/PlaintextRecordLayer.h
• proxygen/fizz/fizz/record/PlaintextRecordLayer.cpp