| /* $Id$ */ |
| /* |
| * Copyright (C) 2008-2011 Teluu Inc. (http://www.teluu.com) |
| * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org> |
| * |
| * 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, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| #include <pjlib-util/base64.h> |
| #include <pj/assert.h> |
| #include <pj/errno.h> |
| |
| #define INV -1 |
| #define PADDING '=' |
| |
| const char base64_char[] = { |
| '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 int base256_char(char c) |
| { |
| if (c >= 'A' && c <= 'Z') |
| return (c - 'A'); |
| else if (c >= 'a' && c <= 'z') |
| return (c - 'a' + 26); |
| else if (c >= '0' && c <= '9') |
| return (c - '0' + 52); |
| else if (c == '+') |
| return (62); |
| else if (c == '/') |
| return (63); |
| else { |
| /* It *may* happen on bad input, so this is not a good idea. |
| * pj_assert(!"Should not happen as '=' should have been filtered"); |
| */ |
| return INV; |
| } |
| } |
| |
| |
| static void base256to64(pj_uint8_t c1, pj_uint8_t c2, pj_uint8_t c3, |
| int padding, char *output) |
| { |
| *output++ = base64_char[c1>>2]; |
| *output++ = base64_char[((c1 & 0x3)<< 4) | ((c2 & 0xF0) >> 4)]; |
| switch (padding) { |
| case 0: |
| *output++ = base64_char[((c2 & 0xF) << 2) | ((c3 & 0xC0) >>6)]; |
| *output = base64_char[c3 & 0x3F]; |
| break; |
| case 1: |
| *output++ = base64_char[((c2 & 0xF) << 2) | ((c3 & 0xC0) >>6)]; |
| *output = PADDING; |
| break; |
| case 2: |
| default: |
| *output++ = PADDING; |
| *output = PADDING; |
| break; |
| } |
| } |
| |
| |
| PJ_DEF(pj_status_t) pj_base64_encode(const pj_uint8_t *input, int in_len, |
| char *output, int *out_len) |
| { |
| const pj_uint8_t *pi = input; |
| pj_uint8_t c1, c2, c3; |
| int i = 0; |
| char *po = output; |
| |
| PJ_ASSERT_RETURN(input && output && out_len, PJ_EINVAL); |
| PJ_ASSERT_RETURN(*out_len >= PJ_BASE256_TO_BASE64_LEN(in_len), |
| PJ_ETOOSMALL); |
| |
| while (i < in_len) { |
| c1 = *pi++; |
| ++i; |
| |
| if (i == in_len) { |
| base256to64(c1, 0, 0, 2, po); |
| po += 4; |
| break; |
| } else { |
| c2 = *pi++; |
| ++i; |
| |
| if (i == in_len) { |
| base256to64(c1, c2, 0, 1, po); |
| po += 4; |
| break; |
| } else { |
| c3 = *pi++; |
| ++i; |
| base256to64(c1, c2, c3, 0, po); |
| } |
| } |
| |
| po += 4; |
| } |
| |
| *out_len = (int)(po - output); |
| return PJ_SUCCESS; |
| } |
| |
| |
| PJ_DEF(pj_status_t) pj_base64_decode(const pj_str_t *input, |
| pj_uint8_t *out, int *out_len) |
| { |
| const char *buf = input->ptr; |
| int len = (int)input->slen; |
| int i, j, k; |
| int c[4]; |
| |
| PJ_ASSERT_RETURN(input && out && out_len, PJ_EINVAL); |
| |
| while (buf[len-1] == '=' && len) |
| --len; |
| |
| PJ_ASSERT_RETURN(*out_len >= PJ_BASE64_TO_BASE256_LEN(len), |
| PJ_ETOOSMALL); |
| |
| for (i=0, j=0; i<len; ) { |
| /* Fill up c, silently ignoring invalid characters */ |
| for (k=0; k<4 && i<len; ++k) { |
| do { |
| c[k] = base256_char(buf[i++]); |
| } while (c[k]==INV && i<len); |
| } |
| |
| if (k<4) { |
| if (k > 1) { |
| out[j++] = (pj_uint8_t)((c[0]<<2) | ((c[1] & 0x30)>>4)); |
| if (k > 2) { |
| out[j++] = (pj_uint8_t) |
| (((c[1] & 0x0F)<<4) | ((c[2] & 0x3C)>>2)); |
| } |
| } |
| break; |
| } |
| |
| out[j++] = (pj_uint8_t)((c[0]<<2) | ((c[1] & 0x30)>>4)); |
| out[j++] = (pj_uint8_t)(((c[1] & 0x0F)<<4) | ((c[2] & 0x3C)>>2)); |
| out[j++] = (pj_uint8_t)(((c[2] & 0x03)<<6) | (c[3] & 0x3F)); |
| } |
| |
| pj_assert(j < *out_len); |
| *out_len = j; |
| |
| return PJ_SUCCESS; |
| } |
| |
| |