/* * RFC 1521 base64 encoding/decoding * * Copyright (C) 2006-2010, Brainspark B.V. * * This file is part of PolarSSL (http://www.polarssl.org) * Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org> * * All rights reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ /* * Pacman Notes: * * Taken from the PolarSSL project at www.polarssl.org under terms of the * GPL. This is from version 0.14.2 of the library, and has been modified * as following, which may be helpful for future updates: * * remove "polarssl/config.h" include * * change include from "polarssl/base64.h" to "base64.h" * * removal of SELF_TEST code */ #include "base64.h" static const unsigned char base64_enc_map[64] = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/' }; static const unsigned char base64_dec_map[128] = { 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 62, 127, 127, 127, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 127, 127, 127, 64, 127, 127, 127, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 127, 127, 127, 127, 127, 127, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 127, 127, 127, 127, 127 }; /* * Encode a buffer into base64 format */ int base64_encode( unsigned char *dst, size_t *dlen, const unsigned char *src, size_t slen ) { size_t i, n; int C1, C2, C3; unsigned char *p; if( slen == 0 ) return( 0 ); n = (slen << 3) / 6; switch( (slen << 3) - (n * 6) ) { case 2: n += 3; break; case 4: n += 2; break; default: break; } if( *dlen < n + 1 ) { *dlen = n + 1; return( POLARSSL_ERR_BASE64_BUFFER_TOO_SMALL ); } n = (slen / 3) * 3; for( i = 0, p = dst; i < n; i += 3 ) { C1 = *src++; C2 = *src++; C3 = *src++; *p++ = base64_enc_map[(C1 >> 2) & 0x3F]; *p++ = base64_enc_map[(((C1 & 3) << 4) + (C2 >> 4)) & 0x3F]; *p++ = base64_enc_map[(((C2 & 15) << 2) + (C3 >> 6)) & 0x3F]; *p++ = base64_enc_map[C3 & 0x3F]; } if( i < slen ) { C1 = *src++; C2 = ((i + 1) < slen) ? *src++ : 0; *p++ = base64_enc_map[(C1 >> 2) & 0x3F]; *p++ = base64_enc_map[(((C1 & 3) << 4) + (C2 >> 4)) & 0x3F]; if( (i + 1) < slen ) *p++ = base64_enc_map[((C2 & 15) << 2) & 0x3F]; else *p++ = '='; *p++ = '='; } *dlen = p - dst; *p = 0; return( 0 ); } /* * Decode a base64-formatted buffer */ int base64_decode( unsigned char *dst, size_t *dlen, const unsigned char *src, size_t slen ) { size_t i, j, n; unsigned long x; unsigned char *p; for( i = j = n = 0; i < slen; i++ ) { if( ( slen - i ) >= 2 && src[i] == '\r' && src[i + 1] == '\n' ) continue; if( src[i] == '\n' ) continue; if( src[i] == '=' && ++j > 2 ) return( POLARSSL_ERR_BASE64_INVALID_CHARACTER ); if( src[i] > 127 || base64_dec_map[src[i]] == 127 ) return( POLARSSL_ERR_BASE64_INVALID_CHARACTER ); if( base64_dec_map[src[i]] < 64 && j != 0 ) return( POLARSSL_ERR_BASE64_INVALID_CHARACTER ); n++; } if( n == 0 ) return( 0 ); n = ((n * 6) + 7) >> 3; if( *dlen < n ) { *dlen = n; return( POLARSSL_ERR_BASE64_BUFFER_TOO_SMALL ); } for( j = 3, n = x = 0, p = dst; i > 0; i--, src++ ) { if( *src == '\r' || *src == '\n' ) continue; j -= ( base64_dec_map[*src] == 64 ); x = (x << 6) | ( base64_dec_map[*src] & 0x3F ); if( ++n == 4 ) { n = 0; if( j > 0 ) *p++ = (unsigned char)( x >> 16 ); if( j > 1 ) *p++ = (unsigned char)( x >> 8 ); if( j > 2 ) *p++ = (unsigned char)( x ); } } *dlen = p - dst; return( 0 ); }