1 /*
2 * base64.c
3 * Release $Name: MATRIXSSL-3-3-0-OPEN $
4 *
5 * Base64 operations
6 */
7 /*
8 * Copyright (c) AuthenTec, Inc. 2011-2012
9 * Copyright (c) PeerSec Networks, 2002-2011
10 * All Rights Reserved
11 *
12 * The latest version of this code is available at http://www.matrixssl.org
13 *
14 * This software is open source; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
18 *
19 * This General Public License does NOT permit incorporating this software
20 * into proprietary programs. If you are unable to comply with the GPL, a
21 * commercial license for this software may be purchased from AuthenTec at
22 * http://www.authentec.com/Products/EmbeddedSecurity/SecurityToolkits.aspx
23 *
24 * This program is distributed in WITHOUT ANY WARRANTY; without even the
25 * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
26 * See the GNU General Public License for more details.
27 *
28 * You should have received a copy of the GNU General Public License
29 * along with this program; if not, write to the Free Software
30 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
31 * http://www.gnu.org/copyleft/gpl.html
32 */
33 /******************************************************************************/
34
35 #include "../cryptoApi.h"
36
37 #ifdef USE_BASE64_DECODE
38
39 static const unsigned char map[256] = {
40 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
41 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
42 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
43 255, 255, 255, 255, 255, 255, 255, 62, 255, 255, 255, 63,
44 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 255, 255,
45 255, 254, 255, 255, 255, 0, 1, 2, 3, 4, 5, 6,
46 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,
47 19, 20, 21, 22, 23, 24, 25, 255, 255, 255, 255, 255,
48 255, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,
49 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
50 49, 50, 51, 255, 255, 255, 255, 255, 255, 255, 255, 255,
51 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
52 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
53 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
54 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
55 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
56 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
57 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
58 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
59 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
60 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
61 255, 255, 255, 255 };
62
psBase64decode(const unsigned char * in,uint32 len,unsigned char * out,uint32 * outlen)63 int32 psBase64decode(const unsigned char *in, uint32 len,
64 unsigned char *out, uint32 *outlen)
65 {
66 unsigned long t, x, y, z;
67 unsigned char c;
68 int32 g;
69
70 if (in == NULL || out == NULL || outlen == NULL) {
71 psTraceCrypto("Arg failure to psBase64decode\n");
72 return PS_ARG_FAIL;
73 }
74 g = 3;
75 for (x = y = z = t = 0; x < len; x++) {
76 c = map[in[x]&0xFF];
77 if (c == 255) {
78 continue;
79 }
80 /*
81 the final = symbols are read and used to trim the remaining bytes
82 */
83 if (c == 254) {
84 c = 0;
85 /*
86 prevent g < 0 which would potentially allow an overflow later
87 */
88 if (--g < 0) {
89 psTraceCrypto("Negative g failure in psBase64decode\n");
90 return PS_LIMIT_FAIL;
91 }
92 } else if (g != 3) {
93 /*
94 we only allow = to be at the end
95 */
96 psTraceCrypto("g failure in psBase64decode\n");
97 return PS_PARSE_FAIL;
98 }
99
100 t = (t<<6)|c;
101
102 if (++y == 4) {
103 if (z + g > *outlen) {
104 psTraceCrypto("outlen too small for psBase64decode\n");
105 return PS_LIMIT_FAIL;
106 }
107 out[z++] = (unsigned char)((t>>16)&255);
108 if (g > 1) {
109 out[z++] = (unsigned char)((t>>8)&255);
110 }
111 if (g > 2) {
112 out[z++] = (unsigned char)(t&255);
113 }
114 y = t = 0;
115 }
116 }
117 if (y != 0) {
118 psTraceCrypto("y failure in psBase64decode\n");
119 return PS_PARSE_FAIL;
120 }
121 *outlen = z;
122 return PS_SUCCESS;
123 }
124
125 #endif /* USE_BASE64_DECODE */
126
127 /******************************************************************************/
128
129