proxygen::Base64 Class Reference

#include <Base64.h>

Static Public Member Functions
static std::string	decode (const std::string &b64message, int padding)
static std::string	urlDecode (const std::string &b64message)
static std::string	encode (folly::ByteRange buffer)
static std::string	urlEncode (folly::ByteRange buffer)

Detailed Description

Definition at line 20 of file Base64.h.

Member Function Documentation

std::string proxygen::Base64::decode ( const std::string &  b64message, int  padding  )

static

Definition at line 51 of file Base64.cpp.

References string.

Referenced by TEST().

                                                                 {
  if (b64message.length() % 4 != 0 || padding >= 3) {
    return std::string();
  }

  std::unique_ptr<BIO, BIODeleter> bio, b64;
  size_t decodeLen = b64message.length() * 3/4 - padding;
  std::string result(decodeLen, '\0');

  bio.reset(BIO_new_mem_buf((void*)b64message.data(), -1));
  if (!bio) {
    return std::string();
  }
  b64.reset(BIO_new(BIO_f_base64()));
  if (!b64) {
    return std::string();
  }
  bio.reset(BIO_push(b64.release(), bio.release()));

  // Do not use newlines to flush buffer
  BIO_set_flags(bio.get(), BIO_FLAGS_BASE64_NO_NL);
  BIO_read(bio.get(), (char*)result.data(), b64message.length());
  DCHECK_LE(result.length(), decodeLen);
  if (result.length() < decodeLen) {
    return std::string();
  }
  return result;
}

std::string proxygen::Base64::encode ( folly::ByteRange  buffer )

static

Definition at line 80 of file Base64.cpp.

References folly::Range< Iter >::data(), folly::Range< Iter >::size(), and string.

Referenced by proxygen::HTTP1xCodec::generateWebsocketAccept(), and proxygen::HTTP1xCodec::generateWebsocketKey().

                                              {
  std::unique_ptr<BIO, BIODeleter> bio, b64;
  BUF_MEM* bufferPtr;

  b64.reset(BIO_new(BIO_f_base64()));
  if (!b64) {
    throw std::bad_alloc();
  }
  bio.reset(BIO_new(BIO_s_mem()));
  if (!bio) {
    throw std::bad_alloc();
  }
  bio.reset(BIO_push(b64.release(), bio.release()));

  // Ignore newlines - write everything in one line
  BIO_set_flags(bio.get(), BIO_FLAGS_BASE64_NO_NL);
  BIO_write(bio.get(), buffer.data(), buffer.size());
  (void)BIO_flush(bio.get());
  BIO_get_mem_ptr(bio.get(), &bufferPtr);
  (void)BIO_set_close(bio.get(), BIO_NOCLOSE);

  std::string result(bufferPtr->data, bufferPtr->length);
  BUF_MEM_free(bufferPtr);
  return result;
}

std::string proxygen::Base64::urlDecode ( const std::string &  b64message )

static

Definition at line 26 of file Base64.cpp.

References c, fizz::decode(), i, string, folly::pushmi::operators::transform, and uint8_t.

                                                          {
  std::unique_ptr<BIO, BIODeleter> bio, b64;
  uint8_t padding = (4 - urlB64message.length() % 4) % 4;
  if (padding == 3) {
    return std::string();
  }

  std::string b64message(urlB64message.length() + padding, 0);
  std::transform(
    urlB64message.begin(), urlB64message.end(), b64message.begin(),
    [](char c) {
      if (c == '-') {
        return '+';
      } else if (c == '_') {
        return '/';
      }
      return c;
    });
  for (auto i = urlB64message.length(); i < urlB64message.length() + padding;
       i++) {
    b64message[i] = '=';
  }
  return decode(b64message, padding);
}

std::string proxygen::Base64::urlEncode ( folly::ByteRange  buffer )

static

Definition at line 107 of file Base64.cpp.

References c, encode(), string, folly::pushmi::operators::transform, and uint8_t.

                                                 {
  std::string result = encode(buffer);
  folly::StringPiece sp(result.data(), result.length());
  uint8_t padding = 0;
  std::transform(
    sp.begin(), sp.end(), result.begin(),
    [&padding](char c) {
      if (c == '+') {
        return '-';
      } else if (c == '/') {
        return '_';
      } else if (c == '=') {
        padding++;
      }
      return c;
    });
  DCHECK_LE(padding, result.length());
  result.resize(result.length() - padding);
  return result;
}

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

• proxygen/lib/utils/Base64.h
• proxygen/lib/utils/Base64.cpp