3 * This file is part of the AVR-Crypto-Lib.
4 * Copyright (C) 2006, 2007, 2008 Daniel Otte (daniel.otte@rub.de)
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
22 * base64 encoder (RFC3548)
30 #include "base64_enc.h"
33 #include <avr/pgmspace.h>
35 char base64_alphabet[64] PROGMEM = {
36 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
37 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
38 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
39 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
40 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
41 'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
42 'w', 'x', 'y', 'z', '0', '1', '2', '3',
43 '4', '5', '6', '7', '8', '9', '+', '/' };
46 char bit6toAscii(uint8_t a){
48 return pgm_read_byte(base64_alphabet+a);
54 char bit6toAscii(uint8_t a){
69 return '/'; /* a == 63 */
78 void base64enc(char* dest,const void* src, uint16_t length){
81 for(i=0; i<length/3; ++i){
82 a[0]= (((uint8_t*)src)[i*3+0])>>2;
83 a[1]= (((((uint8_t*)src)[i*3+0])<<4) | ((((uint8_t*)src)[i*3+1])>>4)) & 0x3F;
84 a[2]= (((((uint8_t*)src)[i*3+1])<<2) | ((((uint8_t*)src)[i*3+2])>>6)) & 0x3F;
85 a[3]= (((uint8_t*)src)[i*3+2]) & 0x3F;
87 *dest++=bit6toAscii(a[j]);
90 /* now we do the rest */
95 a[0]=(((uint8_t*)src)[i*3+0])>>2;
96 a[1]=((((uint8_t*)src)[i*3+0])<<4)&0x3F;
97 *dest++ = bit6toAscii(a[0]);
98 *dest++ = bit6toAscii(a[1]);
103 a[0]= (((uint8_t*)src)[i*3+0])>>2;
104 a[1]= (((((uint8_t*)src)[i*3+0])<<4) | ((((uint8_t*)src)[i*3+1])>>4)) & 0x3F;
105 a[2]= ((((uint8_t*)src)[i*3+1])<<2) & 0x3F;
106 *dest++ = bit6toAscii(a[0]);
107 *dest++ = bit6toAscii(a[1]);
108 *dest++ = bit6toAscii(a[2]);
111 default: /* this will not happen! */