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C

/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.] */
#ifndef OPENSSL_HEADER_BASE64_H
#define OPENSSL_HEADER_BASE64_H
#include <openssl/base.h>
#if defined(__cplusplus)
extern "C" {
#endif
/**
* @file
* @brief base64 encoding and decoding functions.
*
* @details
* For historical reasons, these functions have the `EVP_` prefix but just do
* base64 encoding and decoding. Note that BoringSSL is a cryptography library,
* so these functions are implemented with side channel protections, at a
* performance cost. For other base64 uses, use a general-purpose base64
* implementation.
*/
/**
* @name Encoding Functions
*
* @{
*/
/**
* @brief Base64 encodes bytes from `src` into `dst`.
*
* @details
* Base64 encodes `src_len` bytes from `src` and writes the
* result to `dst` with a trailing `NULL`.
*
* @param [out] dst Base64 encoded value
* @param [in] src Bytes to encode
* @param [in] src_len Number of bytes to encode
*
* @return The number of bytes written, not including the trailing `NULL`
*/
OPENSSL_EXPORT size_t EVP_EncodeBlock(uint8_t *dst, const uint8_t *src,
size_t src_len);
/**
* @brief Calculates the number of bytes needed to encode an input using Base64.
*
* @details
* Sets `*out_len` to the number of bytes that will be needed to call
* #EVP_EncodeBlock on an input of length `len`. `*out_len` includes the final
* `NULL` that #EVP_EncodeBlock writes.
*
* @param [out] out_len Number of bytes needed to Base64 encode a source
* @param [in] len Source length
*
* @retval 1 Success
* @retval 0 Error
*/
OPENSSL_EXPORT int EVP_EncodedLength(size_t *out_len, size_t len);
/** @} Encoding Functions */
/**
* @name Decoding Functions
*
* @{
*/
/**
* @brief Sets the maximum number of bytes need to store a decoded Base64 input.
*
* @param [out] out_len Maximum number of bytes to store decoded input
* @param [in] len Base64 formatted input length
*
* @retval 1 Success
* @retval 0 `len` is not a valid length for a base64-encoded string
*/
OPENSSL_EXPORT int EVP_DecodedLength(size_t *out_len, size_t len);
/**
* @brief Decodes specified number of Base64 formatted bytes to output buffer.
*
* @details
* Decodes `in_len` bytes from base64 and writes `*out_len` bytes to `out`. If
* `*out_len` doesn't have enough bytes for the maximum output size, the
* operation fails.
*
* @param [out] out Decoded output
* @param [out] out_len Number of bytes written to `out`
* @param [in] max_out Length of `out`
* @param [in] in Base64 input buffer
* @param [in] in_len Number of bytes to decode from `in`
*
* @retval 1 Success
* @retval 0 Error
*/
OPENSSL_EXPORT int EVP_DecodeBase64(uint8_t *out, size_t *out_len,
size_t max_out, const uint8_t *in,
size_t in_len);
/** @} Decoding Functions */
/**
* @name Deprecated Functions
*
* OpenSSL provides a streaming base64 implementation, however its behavior is
* very specific to PEM. It is also very lenient of invalid input. Use of any of
* these functions is thus deprecated.
*
* @{
*/
/**
* @brief Returns a newly-allocated EVP_ENCODE_CTX.
*
* @details
* The caller must release the result with #EVP_ENCODE_CTX_free when
* done.
*
* @returns Pointer to newly allocated EVP_ENCODE_CTX or `NULL` on error
*
* @deprecated OpenSSL provides a streaming base64 implementation, however its behavior is very specific to PEM. It is also very lenient of invalid input. Use of any of these functions is thus deprecated.
*/
OPENSSL_EXPORT EVP_ENCODE_CTX *EVP_ENCODE_CTX_new(void);
/**
* @brief Releases memory associated with `ctx`.
*
* @param [in] ctx Pointer to deallocate
*
* @deprecated OpenSSL provides a streaming base64 implementation, however its behavior is very specific to PEM. It is also very lenient of invalid input. Use of any of these functions is thus deprecated.
*/
OPENSSL_EXPORT void EVP_ENCODE_CTX_free(EVP_ENCODE_CTX *ctx);
/**
* @brief Initialises `*ctx`.
*
* @details
* This is typically stack allocated, for an encoding operation.
*
* @param [in,out] ctx Context to initialize
*
* @warning The encoding operation breaks its output with newlines every 64 characters of output (48 characters of input). Use #EVP_EncodeBlock to encode raw base64.
*
* @deprecated OpenSSL provides a streaming base64 implementation, however its behavior is very specific to PEM. It is also very lenient of invalid input. Use of any of these functions is thus deprecated.
*/
OPENSSL_EXPORT void EVP_EncodeInit(EVP_ENCODE_CTX *ctx);
/**
* @brief Encodes bytes from `in` to Base64 and writes the value to `out`.
*
* @details
* Some state may be contained in `ctx` so #EVP_EncodeFinal must be used to
* flush it before using the encoded data.
*
* @param [in,out] ctx Encoding context
* @param [out] out Base64 encoded value
* @param [out] out_len Number of bytes written
* @param [in] in Input buffer
* @param [in] in_len Number of bytes to encode
*
* @retval 1 Success
* @retval 0 Failure or `in_len` was 0
*
* @deprecated OpenSSL provides a streaming base64 implementation, however its behavior is very specific to PEM. It is also very lenient of invalid input. Use of any of these functions is thus deprecated.
*/
OPENSSL_EXPORT int EVP_EncodeUpdate(EVP_ENCODE_CTX *ctx, uint8_t *out,
int *out_len, const uint8_t *in,
size_t in_len);
/**
* @brief Flushes any remaining output bytes from `ctx` to `out`.
*
* @param [in,out] ctx Encoding context
* @param [out] out Output buffer
* @param [out] out_len Number of bytes written to buffer
*
* @deprecated OpenSSL provides a streaming base64 implementation, however its behavior is very specific to PEM. It is also very lenient of invalid input. Use of any of these functions is thus deprecated.
*/
OPENSSL_EXPORT void EVP_EncodeFinal(EVP_ENCODE_CTX *ctx, uint8_t *out,
int *out_len);
/**
* @brief Initialises `*ctx` for a decoding operation.
*
* @details
* This is typically stack allocated.
*
* @param [in,out] ctx Context to initialize
*
* @todo davidben: This isn't a straight-up base64 decode either. Document and/or fix exactly what's going on here; maximum line length and such.
*
* @deprecated OpenSSL provides a streaming base64 implementation, however its behavior is very specific to PEM. It is also very lenient of invalid input. Use of any of these functions is thus deprecated.
*/
OPENSSL_EXPORT void EVP_DecodeInit(EVP_ENCODE_CTX *ctx);
/**
* @brief Decodes bytes from `in` and writes the decoded data to `out`.
*
* @details
* Some state may be contained in `ctx` so #EVP_DecodeFinal must be used to
* flush it before using the decoded data.
*
* @param [in,out] ctx Decoding context
* @param [out] out Decoded bytes
* @param [out] out_len Number of bytes written
* @param [in] in Input buffer
* @param [in] in_len Number of bytes to decode
*
* @retval -1 Error
* @retval 0 The line was short (i.e., it was the last line)
* @retval 1 A full line of input was processed
*
* @deprecated OpenSSL provides a streaming base64 implementation, however its behavior is very specific to PEM. It is also very lenient of invalid input. Use of any of these functions is thus deprecated.
*/
OPENSSL_EXPORT int EVP_DecodeUpdate(EVP_ENCODE_CTX *ctx, uint8_t *out,
int *out_len, const uint8_t *in,
size_t in_len);
/**
* @brief Flushes any remaining output bytes from `ctx` to `out`.
*
* @param [in,out] ctx Decoding context
* @param [out] out Output buffer
* @param [out] out_len Number of bytes written to buffer
*
* @retval 1 Success
* @retval -1 Error
*
* @deprecated OpenSSL provides a streaming base64 implementation, however its behavior is very specific to PEM. It is also very lenient of invalid input. Use of any of these functions is thus deprecated.
*/
OPENSSL_EXPORT int EVP_DecodeFinal(EVP_ENCODE_CTX *ctx, uint8_t *out,
int *out_len);
/**
* @brief Decodes Base64 bytes from `src` and writes value to `dst`.
*
* @param [out] dst Decoded bytes
* @param [in] src Base64 encoded bytes
* @param [in] src_len Number of bytes to decode
*
* @returns Number of bytes written or -1 on error
*
* @warning `EVP_DecodeBlock`'s return value does not take padding into account. It also strips leading whitespace and trailing whitespace and minuses.
*
* @deprecated OpenSSL provides a streaming base64 implementation, however its behavior is very specific to PEM. It is also very lenient of invalid input. Use of any of these functions is thus deprecated.
*/
OPENSSL_EXPORT int EVP_DecodeBlock(uint8_t *dst, const uint8_t *src,
size_t src_len);
/** @} Deprecated Functions */
/**
* @struct evp_encode_ctx_st
* Encoding Context
*/
struct evp_encode_ctx_st {
/**
* @brief Number of valid bytes
*
* @details
* When encoding, `data` will be filled and encoded as a lump. When decoding,
* only the first four bytes of `data` will be used.
*/
unsigned data_used;
/**
* @brief Encoded or decoded data.
*/
uint8_t data[48];
/**
* @brief Indicates that the end of the base64 data has been seen.
*
* @details
* Only used when decoding. Only whitespace can follow.
*/
char eof_seen;
/**
* @brief indicates that invalid base64 data was found.
*
* @details
* This will gitcause all future calls to fail.
*/
char error_encountered;
};
#if defined(__cplusplus)
} // extern C
#endif
#endif // OPENSSL_HEADER_BASE64_H