base64.h
Go to the documentation of this file.
1 /*
2  * Copyright (C) 1996-2018 The Squid Software Foundation and contributors
3  *
4  * Squid software is distributed under GPLv2+ license and includes
5  * contributions from numerous individuals and organizations.
6  * Please see the COPYING and CONTRIBUTORS files for details.
7  */
8 
9 #ifndef _SQUID_BASE64_H
10 #define _SQUID_BASE64_H
11 
12 #if HAVE_NETTLE_BASE64_H && HAVE_NETTLE34_BASE64
13 #include <nettle/base64.h>
14 
15 #else /* Base64 functions copied from Nettle 3.4 under GPLv2, with adjustments */
16 
17 /* base64.h
18 
19  Base-64 encoding and decoding.
20 
21  Copyright (C) 2002 Niels Möller, Dan Egnor
22 
23  This file is part of GNU Nettle.
24 
25  GNU Nettle is free software: you can redistribute it and/or
26  modify it under the terms of either:
27 
28  * the GNU Lesser General Public License as published by the Free
29  Software Foundation; either version 3 of the License, or (at your
30  option) any later version.
31 
32  or
33 
34  * the GNU General Public License as published by the Free
35  Software Foundation; either version 2 of the License, or (at your
36  option) any later version.
37 
38  or both in parallel, as here.
39 
40  GNU Nettle is distributed in the hope that it will be useful,
41  but WITHOUT ANY WARRANTY; without even the implied warranty of
42  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
43  General Public License for more details.
44 
45  You should have received copies of the GNU General Public License and
46  the GNU Lesser General Public License along with this program. If
47  not, see http://www.gnu.org/licenses/.
48 */
49 
50 #ifdef __cplusplus
51 extern "C" {
52 #endif
53 
54 /* Base64 encoding */
55 
56 /* Maximum length of output for base64_encode_update. NOTE: Doesn't
57  * include any padding that base64_encode_final may add. */
58 /* We have at most 4 buffered bits, and a total of (4 + length * 8) bits. */
59 #define BASE64_ENCODE_LENGTH(length) (((length) * 8 + 4)/6)
60 
61 /* Maximum length of output generated by base64_encode_final. */
62 #define BASE64_ENCODE_FINAL_LENGTH 3
63 
64 /* Exact length of output generated by base64_encode_raw, including
65  * padding. */
66 #define BASE64_ENCODE_RAW_LENGTH(length) ((((length) + 2)/3)*4)
67 
69 {
70  const char *alphabet; /* Alphabet to use for encoding */
71  unsigned short word; /* Leftover bits */
72  unsigned char bits; /* Number of bits, always 0, 2, or 4. */
73 };
74 
75 /* Initialize encoding context for base-64 */
76 void
78 
79 /* Initialize encoding context for URL safe alphabet, RFC 4648. */
80 void
82 
83 /* Encodes a single byte. Returns amount of output (always 1 or 2). */
84 size_t
86  char *dst,
87  uint8_t src);
88 
89 /* Returns the number of output characters. DST should point to an
90  * area of size at least BASE64_ENCODE_LENGTH(length). */
91 size_t
93  char *dst,
94  size_t length,
95  const uint8_t *src);
96 
97 /* DST should point to an area of size at least
98  * BASE64_ENCODE_FINAL_LENGTH */
99 size_t
101  char *dst);
102 
103 /* Lower level functions */
104 
105 /* Encodes a string in one go, including any padding at the end.
106  * Generates exactly BASE64_ENCODE_RAW_LENGTH(length) bytes of output.
107  * Supports overlapped operation, if src <= dst. FIXME: Use of overlap
108  * is deprecated, if needed there should be a separate public fucntion
109  * to do that.*/
110 void
111 base64_encode_raw(char *dst, size_t length, const uint8_t *src);
112 
113 void
114 base64_encode_group(char *dst, uint32_t group);
115 
116 /* Base64 decoding */
117 
118 /* Maximum length of output for base64_decode_update. */
119 /* We have at most 6 buffered bits, and a total of (length + 1) * 6 bits. */
120 #define BASE64_DECODE_LENGTH(length) ((((length) + 1) * 6) / 8)
121 
123 {
124  const signed char *table; /* Decoding table */
125  unsigned short word; /* Leftover bits */
126  unsigned char bits; /* Number buffered bits */
127 
128  /* Number of padding characters encountered */
129  unsigned char padding;
130 };
131 
132 /* Initialize decoding context for base-64 */
133 void
135 
136 /* Initialize encoding context for URL safe alphabet, RFC 4648. */
137 void
139 
140 /* Decodes a single byte. Returns amount of output (0 or 1), or -1 on
141  * errors. */
142 int
144  uint8_t *dst,
145  char src);
146 
147 /* Returns 1 on success, 0 on error. DST should point to an area of
148  * size at least BASE64_DECODE_LENGTH(length). The amount of data
149  * generated is returned in *DST_LENGTH. */
150 int
152  size_t *dst_length,
153  uint8_t *dst,
154  size_t src_length,
155  const char *src);
156 
157 /* Returns 1 on success. */
158 int
160 
161 #ifdef __cplusplus
162 }
163 #endif
164 
165 #endif /* HAVE_NETTLE_BASE64_H && HAVE_NETTLE34_BASE64 */
166 
169 # define base64_encode_len(length) (BASE64_ENCODE_LENGTH(length)+BASE64_ENCODE_FINAL_LENGTH+1)
170 
171 #endif /* _SQUID_BASE64_H */
172 
void base64url_decode_init(struct base64_decode_ctx *ctx)
void base64url_encode_init(struct base64_encode_ctx *ctx)
size_t base64_encode_single(struct base64_encode_ctx *ctx, char *dst, uint8_t src)
Definition: base64.c:240
void base64_decode_init(struct base64_decode_ctx *ctx)
Definition: base64.c:54
int base64_decode_single(struct base64_decode_ctx *ctx, uint8_t *dst, char src)
Definition: base64.c:82
void base64_encode_init(struct base64_encode_ctx *ctx)
Definition: base64.c:232
unsigned char bits
Definition: base64.h:126
const signed char * table
Definition: base64.h:124
const char * alphabet
Definition: base64.h:70
size_t base64_encode_final(struct base64_encode_ctx *ctx, char *dst)
Definition: base64.c:308
unsigned char padding
Definition: base64.h:129
void base64_encode_raw(char *dst, size_t length, const uint8_t *src)
Definition: base64.c:217
void base64_encode_group(char *dst, uint32_t group)
Definition: base64.c:223
size_t base64_encode_update(struct base64_encode_ctx *ctx, char *dst, size_t length, const uint8_t *src)
Definition: base64.c:265
unsigned short word
Definition: base64.h:125
int base64_decode_update(struct base64_decode_ctx *ctx, size_t *dst_length, uint8_t *dst, size_t src_length, const char *src)
Definition: base64.c:129
int base64_decode_final(struct base64_decode_ctx *ctx)
Definition: base64.c:159
unsigned short word
Definition: base64.h:71
unsigned char bits
Definition: base64.h:72

 

Introduction

Documentation

Support

Miscellaneous

Web Site Translations

Mirrors