// Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) All rights reserved. // SPDX-License-Identifier: Apache-2.0 #ifndef OPENSSL_HEADER_BASE64_H #define OPENSSL_HEADER_BASE64_H #include #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