/* * Copyright (c) 2006 Ryan Martell. (rdm4@martellventures.com) * * This file is part of FFmpeg. * * FFmpeg 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. * * FFmpeg 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 FFmpeg; 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" #include "intreadwrite.h" /* ---------------- private code */ static const uint8_t map2[256] = { 0xfe, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x3e, 0xff, 0xff, 0xff, 0x3f, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0xff, 0xff, 0xff, 0xfe, 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, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, }; #define BASE64_DEC_STEP(i) do { \ bits = map2[in[i]]; \ if (bits & 0x80) \ goto out ## i; \ v = i ? (v << 6) + bits : bits; \ } while(0) int av_base64_decode(uint8_t *out, const char *in_str, int out_size) { uint8_t *dst = out; uint8_t *end = out + out_size; // no sign extension const uint8_t *in = in_str; unsigned bits = 0xff; unsigned v; while (end - dst > 3) { BASE64_DEC_STEP(0); BASE64_DEC_STEP(1); BASE64_DEC_STEP(2); BASE64_DEC_STEP(3); // Using AV_WB32 directly confuses compiler v = av_be2ne32(v << 8); AV_WN32(dst, v); dst += 3; in += 4; } if (end - dst) { BASE64_DEC_STEP(0); BASE64_DEC_STEP(1); BASE64_DEC_STEP(2); BASE64_DEC_STEP(3); *dst++ = v >> 16; if (end - dst) *dst++ = v >> 8; if (end - dst) *dst++ = v; in += 4; } while (1) { BASE64_DEC_STEP(0); in++; BASE64_DEC_STEP(0); in++; BASE64_DEC_STEP(0); in++; BASE64_DEC_STEP(0); in++; } out3: *dst++ = v >> 10; v <<= 2; out2: *dst++ = v >> 4; out1: out0: return bits & 1 ? -1 : 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 > 3) { i_bits = AV_RB32(in); in += 3; bytes_remaining -= 3; *dst++ = b64[ i_bits>>26 ]; *dst++ = b64[(i_bits>>20) & 0x3F]; *dst++ = b64[(i_bits>>14) & 0x3F]; *dst++ = b64[(i_bits>>8 ) & 0x3F]; } i_bits = 0; while (bytes_remaining) { i_bits = (i_bits << 8) + *in++; bytes_remaining--; i_shift += 8; } while (i_shift > 0) { *dst++ = b64[(i_bits << 6 >> i_shift) & 0x3f]; i_shift -= 6; } while ((dst - ret) & 3) *dst++ = '='; *dst = '\0'; return ret; } #ifdef TEST // LCOV_EXCL_START #undef printf #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)) != data_size) { printf("Failed: cannot decode the encoded string\n" "Encoded:\n%s\n", encoded); return 1; } if ((data2_size = av_base64_decode(data2, encoded, data_size)) != data_size) { printf("Failed: cannot decode with minimal buffer\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; } if (av_base64_decode(NULL, encoded, 0) != 0) { printf("Failed: decode to NULL buffer\n"); return 1; } if (strlen(encoded)) { char *end = strchr(encoded, '='); if (!end) end = encoded + strlen(encoded) - 1; *end = '%'; if (av_base64_decode(NULL, encoded, 0) >= 0) { printf("Failed: error detection\n"); return 1; } } printf("Passed!\n"); return 0; } int main(int argc, char ** argv) { 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=="}, }; char in[1024], out[2048]; 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 (argc>1 && !strcmp(argv[1], "-t")) { memset(in, 123, sizeof(in)); for(i=0; i<10000; i++){ START_TIMER av_base64_encode(out, sizeof(out), in, sizeof(in)); STOP_TIMER("encode") } for(i=0; i<10000; i++){ START_TIMER av_base64_decode(in, out, sizeof(in)); STOP_TIMER("decode") } for(i=0; i<10000; i++){ START_TIMER av_base64_decode(NULL, out, 0); STOP_TIMER("syntax check") } } return error_count; } // LCOV_EXCL_STOP #endif