base64.h 8.8 KB

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  1. /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  2. * All rights reserved.
  3. *
  4. * This package is an SSL implementation written
  5. * by Eric Young (eay@cryptsoft.com).
  6. * The implementation was written so as to conform with Netscapes SSL.
  7. *
  8. * This library is free for commercial and non-commercial use as long as
  9. * the following conditions are aheared to. The following conditions
  10. * apply to all code found in this distribution, be it the RC4, RSA,
  11. * lhash, DES, etc., code; not just the SSL code. The SSL documentation
  12. * included with this distribution is covered by the same copyright terms
  13. * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  14. *
  15. * Copyright remains Eric Young's, and as such any Copyright notices in
  16. * the code are not to be removed.
  17. * If this package is used in a product, Eric Young should be given attribution
  18. * as the author of the parts of the library used.
  19. * This can be in the form of a textual message at program startup or
  20. * in documentation (online or textual) provided with the package.
  21. *
  22. * Redistribution and use in source and binary forms, with or without
  23. * modification, are permitted provided that the following conditions
  24. * are met:
  25. * 1. Redistributions of source code must retain the copyright
  26. * notice, this list of conditions and the following disclaimer.
  27. * 2. Redistributions in binary form must reproduce the above copyright
  28. * notice, this list of conditions and the following disclaimer in the
  29. * documentation and/or other materials provided with the distribution.
  30. * 3. All advertising materials mentioning features or use of this software
  31. * must display the following acknowledgement:
  32. * "This product includes cryptographic software written by
  33. * Eric Young (eay@cryptsoft.com)"
  34. * The word 'cryptographic' can be left out if the rouines from the library
  35. * being used are not cryptographic related :-).
  36. * 4. If you include any Windows specific code (or a derivative thereof) from
  37. * the apps directory (application code) you must include an acknowledgement:
  38. * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  39. *
  40. * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  41. * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  42. * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  43. * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  44. * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  45. * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  46. * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  47. * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  48. * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  49. * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  50. * SUCH DAMAGE.
  51. *
  52. * The licence and distribution terms for any publically available version or
  53. * derivative of this code cannot be changed. i.e. this code cannot simply be
  54. * copied and put under another distribution licence
  55. * [including the GNU Public Licence.] */
  56. #ifndef OPENSSL_HEADER_BASE64_H
  57. #define OPENSSL_HEADER_BASE64_H
  58. #include <openssl/base.h>
  59. #if defined(__cplusplus)
  60. extern "C" {
  61. #endif
  62. // base64 functions.
  63. //
  64. // For historical reasons, these functions have the EVP_ prefix but just do
  65. // base64 encoding and decoding. Note that BoringSSL is a cryptography library,
  66. // so these functions are implemented with side channel protections, at a
  67. // performance cost. For other base64 uses, use a general-purpose base64
  68. // implementation.
  69. // Encoding
  70. // EVP_EncodeBlock encodes |src_len| bytes from |src| and writes the
  71. // result to |dst| with a trailing NUL. It returns the number of bytes
  72. // written, not including this trailing NUL.
  73. OPENSSL_EXPORT size_t EVP_EncodeBlock(uint8_t *dst, const uint8_t *src,
  74. size_t src_len);
  75. // EVP_EncodedLength sets |*out_len| to the number of bytes that will be needed
  76. // to call |EVP_EncodeBlock| on an input of length |len|. This includes the
  77. // final NUL that |EVP_EncodeBlock| writes. It returns one on success or zero
  78. // on error.
  79. OPENSSL_EXPORT int EVP_EncodedLength(size_t *out_len, size_t len);
  80. // Decoding
  81. // EVP_DecodedLength sets |*out_len| to the maximum number of bytes that will
  82. // be needed to call |EVP_DecodeBase64| on an input of length |len|. It returns
  83. // one on success or zero if |len| is not a valid length for a base64-encoded
  84. // string.
  85. OPENSSL_EXPORT int EVP_DecodedLength(size_t *out_len, size_t len);
  86. // EVP_DecodeBase64 decodes |in_len| bytes from base64 and writes
  87. // |*out_len| bytes to |out|. |max_out| is the size of the output
  88. // buffer. If it is not enough for the maximum output size, the
  89. // operation fails. It returns one on success or zero on error.
  90. OPENSSL_EXPORT int EVP_DecodeBase64(uint8_t *out, size_t *out_len,
  91. size_t max_out, const uint8_t *in,
  92. size_t in_len);
  93. // Deprecated functions.
  94. //
  95. // OpenSSL provides a streaming base64 implementation, however its behavior is
  96. // very specific to PEM. It is also very lenient of invalid input. Use of any of
  97. // these functions is thus deprecated.
  98. // EVP_ENCODE_CTX_new returns a newly-allocated |EVP_ENCODE_CTX| or NULL on
  99. // error. The caller must release the result with |EVP_ENCODE_CTX_free| when
  100. // done.
  101. OPENSSL_EXPORT EVP_ENCODE_CTX *EVP_ENCODE_CTX_new(void);
  102. // EVP_ENCODE_CTX_free releases memory associated with |ctx|.
  103. OPENSSL_EXPORT void EVP_ENCODE_CTX_free(EVP_ENCODE_CTX *ctx);
  104. // EVP_EncodeInit initialises |*ctx|, which is typically stack
  105. // allocated, for an encoding operation.
  106. //
  107. // NOTE: The encoding operation breaks its output with newlines every
  108. // 64 characters of output (48 characters of input). Use
  109. // EVP_EncodeBlock to encode raw base64.
  110. OPENSSL_EXPORT void EVP_EncodeInit(EVP_ENCODE_CTX *ctx);
  111. // EVP_EncodeUpdate encodes |in_len| bytes from |in| and writes an encoded
  112. // version of them to |out| and sets |*out_len| to the number of bytes written.
  113. // Some state may be contained in |ctx| so |EVP_EncodeFinal| must be used to
  114. // flush it before using the encoded data.
  115. OPENSSL_EXPORT void EVP_EncodeUpdate(EVP_ENCODE_CTX *ctx, uint8_t *out,
  116. int *out_len, const uint8_t *in,
  117. size_t in_len);
  118. // EVP_EncodeFinal flushes any remaining output bytes from |ctx| to |out| and
  119. // sets |*out_len| to the number of bytes written.
  120. OPENSSL_EXPORT void EVP_EncodeFinal(EVP_ENCODE_CTX *ctx, uint8_t *out,
  121. int *out_len);
  122. // EVP_DecodeInit initialises |*ctx|, which is typically stack allocated, for
  123. // a decoding operation.
  124. //
  125. // TODO(davidben): This isn't a straight-up base64 decode either. Document
  126. // and/or fix exactly what's going on here; maximum line length and such.
  127. OPENSSL_EXPORT void EVP_DecodeInit(EVP_ENCODE_CTX *ctx);
  128. // EVP_DecodeUpdate decodes |in_len| bytes from |in| and writes the decoded
  129. // data to |out| and sets |*out_len| to the number of bytes written. Some state
  130. // may be contained in |ctx| so |EVP_DecodeFinal| must be used to flush it
  131. // before using the encoded data.
  132. //
  133. // It returns -1 on error, one if a full line of input was processed and zero
  134. // if the line was short (i.e. it was the last line).
  135. OPENSSL_EXPORT int EVP_DecodeUpdate(EVP_ENCODE_CTX *ctx, uint8_t *out,
  136. int *out_len, const uint8_t *in,
  137. size_t in_len);
  138. // EVP_DecodeFinal flushes any remaining output bytes from |ctx| to |out| and
  139. // sets |*out_len| to the number of bytes written. It returns one on success
  140. // and minus one on error.
  141. OPENSSL_EXPORT int EVP_DecodeFinal(EVP_ENCODE_CTX *ctx, uint8_t *out,
  142. int *out_len);
  143. // EVP_DecodeBlock encodes |src_len| bytes from |src| and writes the result to
  144. // |dst|. It returns the number of bytes written or -1 on error.
  145. //
  146. // WARNING: EVP_DecodeBlock's return value does not take padding into
  147. // account. It also strips leading whitespace and trailing
  148. // whitespace and minuses.
  149. OPENSSL_EXPORT int EVP_DecodeBlock(uint8_t *dst, const uint8_t *src,
  150. size_t src_len);
  151. struct evp_encode_ctx_st {
  152. // data_used indicates the number of bytes of |data| that are valid. When
  153. // encoding, |data| will be filled and encoded as a lump. When decoding, only
  154. // the first four bytes of |data| will be used.
  155. unsigned data_used;
  156. uint8_t data[48];
  157. // eof_seen indicates that the end of the base64 data has been seen when
  158. // decoding. Only whitespace can follow.
  159. char eof_seen;
  160. // error_encountered indicates that invalid base64 data was found. This will
  161. // cause all future calls to fail.
  162. char error_encountered;
  163. };
  164. #if defined(__cplusplus)
  165. } // extern C
  166. #endif
  167. #endif // OPENSSL_HEADER_BASE64_H