1/* 2 * RFC 1521 base64 encoding/decoding 3 * 4 * Based on XySSL: Copyright (C) 2006-2008 Christophe Devine 5 * 6 * Copyright (C) 2009 Paul Bakker <polarssl_maintainer at polarssl dot org> 7 * 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 14 * * Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * * Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * * Neither the names of PolarSSL or XySSL nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 26 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 27 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 30 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 36#include "polarssl/config.h" 37 38#if defined(POLARSSL_BASE64_C) 39 40#include "polarssl/base64.h" 41 42static const unsigned char base64_enc_map[64] = 43{ 44 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 45 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 46 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 47 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 48 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 49 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', 50 '8', '9', '+', '/' 51}; 52 53static const unsigned char base64_dec_map[128] = 54{ 55 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 56 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 57 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 58 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 59 127, 127, 127, 62, 127, 127, 127, 63, 52, 53, 60 54, 55, 56, 57, 58, 59, 60, 61, 127, 127, 61 127, 64, 127, 127, 127, 0, 1, 2, 3, 4, 62 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 63 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 64 25, 127, 127, 127, 127, 127, 127, 26, 27, 28, 65 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 66 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 67 49, 50, 51, 127, 127, 127, 127, 127 68}; 69 70/* 71 * Encode a buffer into base64 format 72 */ 73int base64_encode( unsigned char *dst, int *dlen, 74 unsigned char *src, int slen ) 75{ 76 int i, n; 77 int C1, C2, C3; 78 unsigned char *p; 79 80 if( slen == 0 ) 81 return( 0 ); 82 83 n = (slen << 3) / 6; 84 85 switch( (slen << 3) - (n * 6) ) 86 { 87 case 2: n += 3; break; 88 case 4: n += 2; break; 89 default: break; 90 } 91 92 if( *dlen < n + 1 ) 93 { 94 *dlen = n + 1; 95 return( POLARSSL_ERR_BASE64_BUFFER_TOO_SMALL ); 96 } 97 98 n = (slen / 3) * 3; 99 100 for( i = 0, p = dst; i < n; i += 3 ) 101 { 102 C1 = *src++; 103 C2 = *src++; 104 C3 = *src++; 105 106 *p++ = base64_enc_map[(C1 >> 2) & 0x3F]; 107 *p++ = base64_enc_map[(((C1 & 3) << 4) + (C2 >> 4)) & 0x3F]; 108 *p++ = base64_enc_map[(((C2 & 15) << 2) + (C3 >> 6)) & 0x3F]; 109 *p++ = base64_enc_map[C3 & 0x3F]; 110 } 111 112 if( i < slen ) 113 { 114 C1 = *src++; 115 C2 = ((i + 1) < slen) ? *src++ : 0; 116 117 *p++ = base64_enc_map[(C1 >> 2) & 0x3F]; 118 *p++ = base64_enc_map[(((C1 & 3) << 4) + (C2 >> 4)) & 0x3F]; 119 120 if( (i + 1) < slen ) 121 *p++ = base64_enc_map[((C2 & 15) << 2) & 0x3F]; 122 else *p++ = '='; 123 124 *p++ = '='; 125 } 126 127 *dlen = p - dst; 128 *p = 0; 129 130 return( 0 ); 131} 132 133/* 134 * Decode a base64-formatted buffer 135 */ 136int base64_decode( unsigned char *dst, int *dlen, 137 unsigned char *src, int slen ) 138{ 139 int i, j, n; 140 unsigned long x; 141 unsigned char *p; 142 143 for( i = j = n = 0; i < slen; i++ ) 144 { 145 if( ( slen - i ) >= 2 && 146 src[i] == '\r' && src[i + 1] == '\n' ) 147 continue; 148 149 if( src[i] == '\n' ) 150 continue; 151 152 if( src[i] == '=' && ++j > 2 ) 153 return( POLARSSL_ERR_BASE64_INVALID_CHARACTER ); 154 155 if( src[i] > 127 || base64_dec_map[src[i]] == 127 ) 156 return( POLARSSL_ERR_BASE64_INVALID_CHARACTER ); 157 158 if( base64_dec_map[src[i]] < 64 && j != 0 ) 159 return( POLARSSL_ERR_BASE64_INVALID_CHARACTER ); 160 161 n++; 162 } 163 164 if( n == 0 ) 165 return( 0 ); 166 167 n = ((n * 6) + 7) >> 3; 168 169 if( *dlen < n ) 170 { 171 *dlen = n; 172 return( POLARSSL_ERR_BASE64_BUFFER_TOO_SMALL ); 173 } 174 175 for( j = 3, n = x = 0, p = dst; i > 0; i--, src++ ) 176 { 177 if( *src == '\r' || *src == '\n' ) 178 continue; 179 180 j -= ( base64_dec_map[*src] == 64 ); 181 x = (x << 6) | ( base64_dec_map[*src] & 0x3F ); 182 183 if( ++n == 4 ) 184 { 185 n = 0; 186 if( j > 0 ) *p++ = (unsigned char)( x >> 16 ); 187 if( j > 1 ) *p++ = (unsigned char)( x >> 8 ); 188 if( j > 2 ) *p++ = (unsigned char)( x ); 189 } 190 } 191 192 *dlen = p - dst; 193 194 return( 0 ); 195} 196 197#if defined(POLARSSL_SELF_TEST) 198 199#include <string.h> 200#include <stdio.h> 201 202static const unsigned char base64_test_dec[64] = 203{ 204 0x24, 0x48, 0x6E, 0x56, 0x87, 0x62, 0x5A, 0xBD, 205 0xBF, 0x17, 0xD9, 0xA2, 0xC4, 0x17, 0x1A, 0x01, 206 0x94, 0xED, 0x8F, 0x1E, 0x11, 0xB3, 0xD7, 0x09, 207 0x0C, 0xB6, 0xE9, 0x10, 0x6F, 0x22, 0xEE, 0x13, 208 0xCA, 0xB3, 0x07, 0x05, 0x76, 0xC9, 0xFA, 0x31, 209 0x6C, 0x08, 0x34, 0xFF, 0x8D, 0xC2, 0x6C, 0x38, 210 0x00, 0x43, 0xE9, 0x54, 0x97, 0xAF, 0x50, 0x4B, 211 0xD1, 0x41, 0xBA, 0x95, 0x31, 0x5A, 0x0B, 0x97 212}; 213 214static const unsigned char base64_test_enc[] = 215 "JEhuVodiWr2/F9mixBcaAZTtjx4Rs9cJDLbpEG8i7hPK" 216 "swcFdsn6MWwINP+Nwmw4AEPpVJevUEvRQbqVMVoLlw=="; 217 218/* 219 * Checkup routine 220 */ 221int base64_self_test( int verbose ) 222{ 223 int len; 224 unsigned char *src, buffer[128]; 225 226 if( verbose != 0 ) 227 printf( " Base64 encoding test: " ); 228 229 len = sizeof( buffer ); 230 src = (unsigned char *) base64_test_dec; 231 232 if( base64_encode( buffer, &len, src, 64 ) != 0 || 233 memcmp( base64_test_enc, buffer, 88 ) != 0 ) 234 { 235 if( verbose != 0 ) 236 printf( "failed\n" ); 237 238 return( 1 ); 239 } 240 241 if( verbose != 0 ) 242 printf( "passed\n Base64 decoding test: " ); 243 244 len = sizeof( buffer ); 245 src = (unsigned char *) base64_test_enc; 246 247 if( base64_decode( buffer, &len, src, 88 ) != 0 || 248 memcmp( base64_test_dec, buffer, 64 ) != 0 ) 249 { 250 if( verbose != 0 ) 251 printf( "failed\n" ); 252 253 return( 1 ); 254 } 255 256 if( verbose != 0 ) 257 printf( "passed\n\n" ); 258 259 return( 0 ); 260} 261 262#endif 263 264#endif 265