/* * Copyright (c) 2006 Ryan Martell. (rdm4@martellventures.com) * * This file is part of Libav. * * Libav is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * Libav 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * @brief Base64 encode/decode * @author Ryan Martell <rdm4@martellventures.com> (with lots of Michael) */ #include "common.h" #include "base64.h" /* ---------------- private code */ static const uint8_t map2[] = { 0x3e, 0xff, 0xff, 0xff, 0x3f, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33 }; int av_base64_decode(uint8_t *out, const char *in, int out_size) { int i; unsigned v = 0; uint8_t *dst = out; for (i = 0; in[i] && in[i] != '='; i++) { unsigned int index= in[i]-43; if (index>=FF_ARRAY_ELEMS(map2) || map2[index] == 0xff) return -1; v = (v << 6) + map2[index]; if (i & 3) { if (dst - out < out_size) { *dst++ = v >> (6 - 2 * (i & 3)); } } } return dst - out; } /***************************************************************************** * b64_encode: Stolen from VLC's http.c. * Simplified by Michael. * Fixed edge cases and made it work from data (vs. strings) by Ryan. *****************************************************************************/ char *av_base64_encode(char *out, int out_size, const uint8_t *in, int in_size) { static const char b64[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; char *ret, *dst; unsigned i_bits = 0; int i_shift = 0; int bytes_remaining = in_size; if (in_size >= UINT_MAX / 4 || out_size < AV_BASE64_SIZE(in_size)) return NULL; ret = dst = out; while (bytes_remaining) { i_bits = (i_bits << 8) + *in++; bytes_remaining--; i_shift += 8; do { *dst++ = b64[(i_bits << 6 >> i_shift) & 0x3f]; i_shift -= 6; } while (i_shift > 6 || (bytes_remaining == 0 && i_shift > 0)); } while ((dst - ret) & 3) *dst++ = '='; *dst = '\0'; return ret; } #ifdef TEST #define MAX_DATA_SIZE 1024 #define MAX_ENCODED_SIZE 2048 static int test_encode_decode(const uint8_t *data, unsigned int data_size, const char *encoded_ref) { char encoded[MAX_ENCODED_SIZE]; uint8_t data2[MAX_DATA_SIZE]; int data2_size, max_data2_size = MAX_DATA_SIZE; if (!av_base64_encode(encoded, MAX_ENCODED_SIZE, data, data_size)) { printf("Failed: cannot encode the input data\n"); return 1; } if (encoded_ref && strcmp(encoded, encoded_ref)) { printf("Failed: encoded string differs from reference\n" "Encoded:\n%s\nReference:\n%s\n", encoded, encoded_ref); return 1; } if ((data2_size = av_base64_decode(data2, encoded, max_data2_size)) < 0) { printf("Failed: cannot decode the encoded string\n" "Encoded:\n%s\n", encoded); return 1; } if (memcmp(data2, data, data_size)) { printf("Failed: encoded/decoded data differs from original data\n"); return 1; } printf("Passed!\n"); return 0; } int main(void) { int i, error_count = 0; struct test { const uint8_t *data; const char *encoded_ref; } tests[] = { { "", ""}, { "1", "MQ=="}, { "22", "MjI="}, { "333", "MzMz"}, { "4444", "NDQ0NA=="}, { "55555", "NTU1NTU="}, { "666666", "NjY2NjY2"}, { "abc:def", "YWJjOmRlZg=="}, }; printf("Encoding/decoding tests\n"); for (i = 0; i < FF_ARRAY_ELEMS(tests); i++) error_count += test_encode_decode(tests[i].data, strlen(tests[i].data), tests[i].encoded_ref); if (error_count) printf("Error Count: %d.\n", error_count); return !!error_count; } #endif