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
57#ifndef OPENSSL_HEADER_BASE64_H
58#define OPENSSL_HEADER_BASE64_H
59
60#include <openssl/base.h>
61
62#if defined(__cplusplus)
63extern "C" {
64#endif
65
66
67// base64 functions.
68//
69// For historical reasons, these functions have the EVP_ prefix but just do
70// base64 encoding and decoding. Note that BoringSSL is a cryptography library,
71// so these functions are implemented with side channel protections, at a
72// performance cost. For other base64 uses, use a general-purpose base64
73// implementation.
74
75
76// Encoding
77
78// EVP_EncodeBlock encodes |src_len| bytes from |src| and writes the
79// result to |dst| with a trailing NUL. It returns the number of bytes
80// written, not including this trailing NUL.
81OPENSSL_EXPORT size_t EVP_EncodeBlock(uint8_t *dst, const uint8_t *src,
82 size_t src_len);
83
84// EVP_EncodedLength sets |*out_len| to the number of bytes that will be needed
85// to call |EVP_EncodeBlock| on an input of length |len|. This includes the
86// final NUL that |EVP_EncodeBlock| writes. It returns one on success or zero
87// on error.
88OPENSSL_EXPORT int EVP_EncodedLength(size_t *out_len, size_t len);
89
90
91// Decoding
92
93// EVP_DecodedLength sets |*out_len| to the maximum number of bytes that will
94// be needed to call |EVP_DecodeBase64| on an input of length |len|. It returns
95// one on success or zero if |len| is not a valid length for a base64-encoded
96// string.
97OPENSSL_EXPORT int EVP_DecodedLength(size_t *out_len, size_t len);
98
99// EVP_DecodeBase64 decodes |in_len| bytes from base64 and writes
100// |*out_len| bytes to |out|. |max_out| is the size of the output
101// buffer. If it is not enough for the maximum output size, the
102// operation fails. It returns one on success or zero on error.
103OPENSSL_EXPORT int EVP_DecodeBase64(uint8_t *out, size_t *out_len,
104 size_t max_out, const uint8_t *in,
105 size_t in_len);
106
107
108// Deprecated functions.
109//
110// OpenSSL provides a streaming base64 implementation, however its behavior is
111// very specific to PEM. It is also very lenient of invalid input. Use of any of
112// these functions is thus deprecated.
113
114// EVP_EncodeInit initialises |*ctx|, which is typically stack
115// allocated, for an encoding operation.
116//
117// NOTE: The encoding operation breaks its output with newlines every
118// 64 characters of output (48 characters of input). Use
119// EVP_EncodeBlock to encode raw base64.
120OPENSSL_EXPORT void EVP_EncodeInit(EVP_ENCODE_CTX *ctx);
121
122// EVP_EncodeUpdate encodes |in_len| bytes from |in| and writes an encoded
123// version of them to |out| and sets |*out_len| to the number of bytes written.
124// Some state may be contained in |ctx| so |EVP_EncodeFinal| must be used to
125// flush it before using the encoded data.
126OPENSSL_EXPORT void EVP_EncodeUpdate(EVP_ENCODE_CTX *ctx, uint8_t *out,
127 int *out_len, const uint8_t *in,
128 size_t in_len);
129
130// EVP_EncodeFinal flushes any remaining output bytes from |ctx| to |out| and
131// sets |*out_len| to the number of bytes written.
132OPENSSL_EXPORT void EVP_EncodeFinal(EVP_ENCODE_CTX *ctx, uint8_t *out,
133 int *out_len);
134
135// EVP_DecodeInit initialises |*ctx|, which is typically stack allocated, for
136// a decoding operation.
137//
138// TODO(davidben): This isn't a straight-up base64 decode either. Document
139// and/or fix exactly what's going on here; maximum line length and such.
140OPENSSL_EXPORT void EVP_DecodeInit(EVP_ENCODE_CTX *ctx);
141
142// EVP_DecodeUpdate decodes |in_len| bytes from |in| and writes the decoded
143// data to |out| and sets |*out_len| to the number of bytes written. Some state
144// may be contained in |ctx| so |EVP_DecodeFinal| must be used to flush it
145// before using the encoded data.
146//
147// It returns -1 on error, one if a full line of input was processed and zero
148// if the line was short (i.e. it was the last line).
149OPENSSL_EXPORT int EVP_DecodeUpdate(EVP_ENCODE_CTX *ctx, uint8_t *out,
150 int *out_len, const uint8_t *in,
151 size_t in_len);
152
153// EVP_DecodeFinal flushes any remaining output bytes from |ctx| to |out| and
154// sets |*out_len| to the number of bytes written. It returns one on success
155// and minus one on error.
156OPENSSL_EXPORT int EVP_DecodeFinal(EVP_ENCODE_CTX *ctx, uint8_t *out,
157 int *out_len);
158
159// EVP_DecodeBlock encodes |src_len| bytes from |src| and writes the result to
160// |dst|. It returns the number of bytes written or -1 on error.
161//
162// WARNING: EVP_DecodeBlock's return value does not take padding into
163// account. It also strips leading whitespace and trailing
164// whitespace and minuses.
165OPENSSL_EXPORT int EVP_DecodeBlock(uint8_t *dst, const uint8_t *src,
166 size_t src_len);
167
168
169struct evp_encode_ctx_st {
170 // data_used indicates the number of bytes of |data| that are valid. When
171 // encoding, |data| will be filled and encoded as a lump. When decoding, only
172 // the first four bytes of |data| will be used.
173 unsigned data_used;
174 uint8_t data[48];
175
176 // eof_seen indicates that the end of the base64 data has been seen when
177 // decoding. Only whitespace can follow.
178 char eof_seen;
179
180 // error_encountered indicates that invalid base64 data was found. This will
181 // cause all future calls to fail.
182 char error_encountered;
183};
184
185
186#if defined(__cplusplus)
187} // extern C
188#endif
189
190#endif // OPENSSL_HEADER_BASE64_H
191