1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/nsprpub/lib/libc/src/base64.c Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,416 @@
1.4 +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#include "plbase64.h"
1.10 +#include "prlog.h" /* For PR_NOT_REACHED */
1.11 +#include "prmem.h" /* for malloc / PR_MALLOC */
1.12 +
1.13 +#include <string.h> /* for strlen */
1.14 +
1.15 +static unsigned char *base = (unsigned char *)"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
1.16 +
1.17 +static void
1.18 +encode3to4
1.19 +(
1.20 + const unsigned char *src,
1.21 + unsigned char *dest
1.22 +)
1.23 +{
1.24 + PRUint32 b32 = (PRUint32)0;
1.25 + PRIntn i, j = 18;
1.26 +
1.27 + for( i = 0; i < 3; i++ )
1.28 + {
1.29 + b32 <<= 8;
1.30 + b32 |= (PRUint32)src[i];
1.31 + }
1.32 +
1.33 + for( i = 0; i < 4; i++ )
1.34 + {
1.35 + dest[i] = base[ (PRUint32)((b32>>j) & 0x3F) ];
1.36 + j -= 6;
1.37 + }
1.38 +
1.39 + return;
1.40 +}
1.41 +
1.42 +static void
1.43 +encode2to4
1.44 +(
1.45 + const unsigned char *src,
1.46 + unsigned char *dest
1.47 +)
1.48 +{
1.49 + dest[0] = base[ (PRUint32)((src[0]>>2) & 0x3F) ];
1.50 + dest[1] = base[ (PRUint32)(((src[0] & 0x03) << 4) | ((src[1] >> 4) & 0x0F)) ];
1.51 + dest[2] = base[ (PRUint32)((src[1] & 0x0F) << 2) ];
1.52 + dest[3] = (unsigned char)'=';
1.53 + return;
1.54 +}
1.55 +
1.56 +static void
1.57 +encode1to4
1.58 +(
1.59 + const unsigned char *src,
1.60 + unsigned char *dest
1.61 +)
1.62 +{
1.63 + dest[0] = base[ (PRUint32)((src[0]>>2) & 0x3F) ];
1.64 + dest[1] = base[ (PRUint32)((src[0] & 0x03) << 4) ];
1.65 + dest[2] = (unsigned char)'=';
1.66 + dest[3] = (unsigned char)'=';
1.67 + return;
1.68 +}
1.69 +
1.70 +static void
1.71 +encode
1.72 +(
1.73 + const unsigned char *src,
1.74 + PRUint32 srclen,
1.75 + unsigned char *dest
1.76 +)
1.77 +{
1.78 + while( srclen >= 3 )
1.79 + {
1.80 + encode3to4(src, dest);
1.81 + src += 3;
1.82 + dest += 4;
1.83 + srclen -= 3;
1.84 + }
1.85 +
1.86 + switch( srclen )
1.87 + {
1.88 + case 2:
1.89 + encode2to4(src, dest);
1.90 + break;
1.91 + case 1:
1.92 + encode1to4(src, dest);
1.93 + break;
1.94 + case 0:
1.95 + break;
1.96 + default:
1.97 + PR_NOT_REACHED("coding error");
1.98 + }
1.99 +
1.100 + return;
1.101 +}
1.102 +
1.103 +/*
1.104 + * PL_Base64Encode
1.105 + *
1.106 + * If the destination argument is NULL, a return buffer is
1.107 + * allocated, and the data therein will be null-terminated.
1.108 + * If the destination argument is not NULL, it is assumed to
1.109 + * be of sufficient size, and the contents will not be null-
1.110 + * terminated by this routine.
1.111 + *
1.112 + * Returns null if the allocation fails.
1.113 + */
1.114 +
1.115 +PR_IMPLEMENT(char *)
1.116 +PL_Base64Encode
1.117 +(
1.118 + const char *src,
1.119 + PRUint32 srclen,
1.120 + char *dest
1.121 +)
1.122 +{
1.123 + if( 0 == srclen )
1.124 + {
1.125 + size_t len = strlen(src);
1.126 + srclen = len;
1.127 + /* Detect truncation. */
1.128 + if( srclen != len )
1.129 + {
1.130 + return (char *)0;
1.131 + }
1.132 + }
1.133 +
1.134 + if( (char *)0 == dest )
1.135 + {
1.136 + PRUint32 destlen;
1.137 + /* Ensure all PRUint32 values stay within range. */
1.138 + if( srclen > (PR_UINT32_MAX/4) * 3 )
1.139 + {
1.140 + return (char *)0;
1.141 + }
1.142 + destlen = ((srclen + 2)/3) * 4;
1.143 + dest = (char *)PR_MALLOC(destlen + 1);
1.144 + if( (char *)0 == dest )
1.145 + {
1.146 + return (char *)0;
1.147 + }
1.148 + dest[ destlen ] = (char)0; /* null terminate */
1.149 + }
1.150 +
1.151 + encode((const unsigned char *)src, srclen, (unsigned char *)dest);
1.152 + return dest;
1.153 +}
1.154 +
1.155 +static PRInt32
1.156 +codetovalue
1.157 +(
1.158 + unsigned char c
1.159 +)
1.160 +{
1.161 + if( (c >= (unsigned char)'A') && (c <= (unsigned char)'Z') )
1.162 + {
1.163 + return (PRInt32)(c - (unsigned char)'A');
1.164 + }
1.165 + else if( (c >= (unsigned char)'a') && (c <= (unsigned char)'z') )
1.166 + {
1.167 + return ((PRInt32)(c - (unsigned char)'a') +26);
1.168 + }
1.169 + else if( (c >= (unsigned char)'0') && (c <= (unsigned char)'9') )
1.170 + {
1.171 + return ((PRInt32)(c - (unsigned char)'0') +52);
1.172 + }
1.173 + else if( (unsigned char)'+' == c )
1.174 + {
1.175 + return (PRInt32)62;
1.176 + }
1.177 + else if( (unsigned char)'/' == c )
1.178 + {
1.179 + return (PRInt32)63;
1.180 + }
1.181 + else
1.182 + {
1.183 + return -1;
1.184 + }
1.185 +}
1.186 +
1.187 +static PRStatus
1.188 +decode4to3
1.189 +(
1.190 + const unsigned char *src,
1.191 + unsigned char *dest
1.192 +)
1.193 +{
1.194 + PRUint32 b32 = (PRUint32)0;
1.195 + PRInt32 bits;
1.196 + PRIntn i;
1.197 +
1.198 + for( i = 0; i < 4; i++ )
1.199 + {
1.200 + bits = codetovalue(src[i]);
1.201 + if( bits < 0 )
1.202 + {
1.203 + return PR_FAILURE;
1.204 + }
1.205 +
1.206 + b32 <<= 6;
1.207 + b32 |= bits;
1.208 + }
1.209 +
1.210 + dest[0] = (unsigned char)((b32 >> 16) & 0xFF);
1.211 + dest[1] = (unsigned char)((b32 >> 8) & 0xFF);
1.212 + dest[2] = (unsigned char)((b32 ) & 0xFF);
1.213 +
1.214 + return PR_SUCCESS;
1.215 +}
1.216 +
1.217 +static PRStatus
1.218 +decode3to2
1.219 +(
1.220 + const unsigned char *src,
1.221 + unsigned char *dest
1.222 +)
1.223 +{
1.224 + PRUint32 b32 = (PRUint32)0;
1.225 + PRInt32 bits;
1.226 + PRUint32 ubits;
1.227 +
1.228 + bits = codetovalue(src[0]);
1.229 + if( bits < 0 )
1.230 + {
1.231 + return PR_FAILURE;
1.232 + }
1.233 +
1.234 + b32 = (PRUint32)bits;
1.235 + b32 <<= 6;
1.236 +
1.237 + bits = codetovalue(src[1]);
1.238 + if( bits < 0 )
1.239 + {
1.240 + return PR_FAILURE;
1.241 + }
1.242 +
1.243 + b32 |= (PRUint32)bits;
1.244 + b32 <<= 4;
1.245 +
1.246 + bits = codetovalue(src[2]);
1.247 + if( bits < 0 )
1.248 + {
1.249 + return PR_FAILURE;
1.250 + }
1.251 +
1.252 + ubits = (PRUint32)bits;
1.253 + b32 |= (ubits >> 2);
1.254 +
1.255 + dest[0] = (unsigned char)((b32 >> 8) & 0xFF);
1.256 + dest[1] = (unsigned char)((b32 ) & 0xFF);
1.257 +
1.258 + return PR_SUCCESS;
1.259 +}
1.260 +
1.261 +static PRStatus
1.262 +decode2to1
1.263 +(
1.264 + const unsigned char *src,
1.265 + unsigned char *dest
1.266 +)
1.267 +{
1.268 + PRUint32 b32;
1.269 + PRUint32 ubits;
1.270 + PRInt32 bits;
1.271 +
1.272 + bits = codetovalue(src[0]);
1.273 + if( bits < 0 )
1.274 + {
1.275 + return PR_FAILURE;
1.276 + }
1.277 +
1.278 + ubits = (PRUint32)bits;
1.279 + b32 = (ubits << 2);
1.280 +
1.281 + bits = codetovalue(src[1]);
1.282 + if( bits < 0 )
1.283 + {
1.284 + return PR_FAILURE;
1.285 + }
1.286 +
1.287 + ubits = (PRUint32)bits;
1.288 + b32 |= (ubits >> 4);
1.289 +
1.290 + dest[0] = (unsigned char)b32;
1.291 +
1.292 + return PR_SUCCESS;
1.293 +}
1.294 +
1.295 +static PRStatus
1.296 +decode
1.297 +(
1.298 + const unsigned char *src,
1.299 + PRUint32 srclen,
1.300 + unsigned char *dest
1.301 +)
1.302 +{
1.303 + PRStatus rv;
1.304 +
1.305 + while( srclen >= 4 )
1.306 + {
1.307 + rv = decode4to3(src, dest);
1.308 + if( PR_SUCCESS != rv )
1.309 + {
1.310 + return PR_FAILURE;
1.311 + }
1.312 +
1.313 + src += 4;
1.314 + dest += 3;
1.315 + srclen -= 4;
1.316 + }
1.317 +
1.318 + switch( srclen )
1.319 + {
1.320 + case 3:
1.321 + rv = decode3to2(src, dest);
1.322 + break;
1.323 + case 2:
1.324 + rv = decode2to1(src, dest);
1.325 + break;
1.326 + case 1:
1.327 + rv = PR_FAILURE;
1.328 + break;
1.329 + case 0:
1.330 + rv = PR_SUCCESS;
1.331 + break;
1.332 + default:
1.333 + PR_NOT_REACHED("coding error");
1.334 + }
1.335 +
1.336 + return rv;
1.337 +}
1.338 +
1.339 +/*
1.340 + * PL_Base64Decode
1.341 + *
1.342 + * If the destination argument is NULL, a return buffer is
1.343 + * allocated and the data therein will be null-terminated.
1.344 + * If the destination argument is not null, it is assumed
1.345 + * to be of sufficient size, and the data will not be null-
1.346 + * terminated by this routine.
1.347 + *
1.348 + * Returns null if the allocation fails, or if the source string is
1.349 + * not well-formed.
1.350 + */
1.351 +
1.352 +PR_IMPLEMENT(char *)
1.353 +PL_Base64Decode
1.354 +(
1.355 + const char *src,
1.356 + PRUint32 srclen,
1.357 + char *dest
1.358 +)
1.359 +{
1.360 + PRStatus status;
1.361 + PRBool allocated = PR_FALSE;
1.362 +
1.363 + if( (char *)0 == src )
1.364 + {
1.365 + return (char *)0;
1.366 + }
1.367 +
1.368 + if( 0 == srclen )
1.369 + {
1.370 + size_t len = strlen(src);
1.371 + srclen = len;
1.372 + /* Detect truncation. */
1.373 + if( srclen != len )
1.374 + {
1.375 + return (char *)0;
1.376 + }
1.377 + }
1.378 +
1.379 + if( srclen && (0 == (srclen & 3)) )
1.380 + {
1.381 + if( (char)'=' == src[ srclen-1 ] )
1.382 + {
1.383 + if( (char)'=' == src[ srclen-2 ] )
1.384 + {
1.385 + srclen -= 2;
1.386 + }
1.387 + else
1.388 + {
1.389 + srclen -= 1;
1.390 + }
1.391 + }
1.392 + }
1.393 +
1.394 + if( (char *)0 == dest )
1.395 + {
1.396 + /* The following computes ((srclen * 3) / 4) without overflow. */
1.397 + PRUint32 destlen = (srclen / 4) * 3 + ((srclen % 4) * 3) / 4;
1.398 + dest = (char *)PR_MALLOC(destlen + 1);
1.399 + if( (char *)0 == dest )
1.400 + {
1.401 + return (char *)0;
1.402 + }
1.403 + dest[ destlen ] = (char)0; /* null terminate */
1.404 + allocated = PR_TRUE;
1.405 + }
1.406 +
1.407 + status = decode((const unsigned char *)src, srclen, (unsigned char *)dest);
1.408 + if( PR_SUCCESS != status )
1.409 + {
1.410 + if( PR_TRUE == allocated )
1.411 + {
1.412 + PR_DELETE(dest);
1.413 + }
1.414 +
1.415 + return (char *)0;
1.416 + }
1.417 +
1.418 + return dest;
1.419 +}
