yading@11: /*
yading@11:  * Copyright (c) 2006 Ryan Martell. (rdm4@martellventures.com)
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: /**
yading@11:  * @file
yading@11:  * @brief Base64 encode/decode
yading@11:  * @author Ryan Martell <rdm4@martellventures.com> (with lots of Michael)
yading@11:  */
yading@11: 
yading@11: #include "common.h"
yading@11: #include "base64.h"
yading@11: #include "intreadwrite.h"
yading@11: 
yading@11: /* ---------------- private code */
yading@11: static const uint8_t map2[256] =
yading@11: {
yading@11:     0xfe, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff,
yading@11: 
yading@11:     0x3e, 0xff, 0xff, 0xff, 0x3f, 0x34, 0x35, 0x36,
yading@11:     0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0xff,
yading@11:     0xff, 0xff, 0xfe, 0xff, 0xff, 0xff, 0x00, 0x01,
yading@11:     0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
yading@11:     0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11,
yading@11:     0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x1a, 0x1b,
yading@11:     0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23,
yading@11:     0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b,
yading@11:     0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33,
yading@11: 
yading@11:                       0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11:     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
yading@11: };
yading@11: 
yading@11: #define BASE64_DEC_STEP(i) do { \
yading@11:     bits = map2[in[i]]; \
yading@11:     if (bits & 0x80) \
yading@11:         goto out ## i; \
yading@11:     v = i ? (v << 6) + bits : bits; \
yading@11: } while(0)
yading@11: 
yading@11: int av_base64_decode(uint8_t *out, const char *in_str, int out_size)
yading@11: {
yading@11:     uint8_t *dst = out;
yading@11:     uint8_t *end = out + out_size;
yading@11:     // no sign extension
yading@11:     const uint8_t *in = in_str;
yading@11:     unsigned bits = 0xff;
yading@11:     unsigned v;
yading@11: 
yading@11:     while (end - dst > 3) {
yading@11:         BASE64_DEC_STEP(0);
yading@11:         BASE64_DEC_STEP(1);
yading@11:         BASE64_DEC_STEP(2);
yading@11:         BASE64_DEC_STEP(3);
yading@11:         // Using AV_WB32 directly confuses compiler
yading@11:         v = av_be2ne32(v << 8);
yading@11:         AV_WN32(dst, v);
yading@11:         dst += 3;
yading@11:         in += 4;
yading@11:     }
yading@11:     if (end - dst) {
yading@11:         BASE64_DEC_STEP(0);
yading@11:         BASE64_DEC_STEP(1);
yading@11:         BASE64_DEC_STEP(2);
yading@11:         BASE64_DEC_STEP(3);
yading@11:         *dst++ = v >> 16;
yading@11:         if (end - dst)
yading@11:             *dst++ = v >> 8;
yading@11:         if (end - dst)
yading@11:             *dst++ = v;
yading@11:         in += 4;
yading@11:     }
yading@11:     while (1) {
yading@11:         BASE64_DEC_STEP(0);
yading@11:         in++;
yading@11:         BASE64_DEC_STEP(0);
yading@11:         in++;
yading@11:         BASE64_DEC_STEP(0);
yading@11:         in++;
yading@11:         BASE64_DEC_STEP(0);
yading@11:         in++;
yading@11:     }
yading@11: 
yading@11: out3:
yading@11:     *dst++ = v >> 10;
yading@11:     v <<= 2;
yading@11: out2:
yading@11:     *dst++ = v >> 4;
yading@11: out1:
yading@11: out0:
yading@11:     return bits & 1 ? AVERROR_INVALIDDATA : dst - out;
yading@11: }
yading@11: 
yading@11: /*****************************************************************************
yading@11: * b64_encode: Stolen from VLC's http.c.
yading@11: * Simplified by Michael.
yading@11: * Fixed edge cases and made it work from data (vs. strings) by Ryan.
yading@11: *****************************************************************************/
yading@11: 
yading@11: char *av_base64_encode(char *out, int out_size, const uint8_t *in, int in_size)
yading@11: {
yading@11:     static const char b64[] =
yading@11:         "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
yading@11:     char *ret, *dst;
yading@11:     unsigned i_bits = 0;
yading@11:     int i_shift = 0;
yading@11:     int bytes_remaining = in_size;
yading@11: 
yading@11:     if (in_size >= UINT_MAX / 4 ||
yading@11:         out_size < AV_BASE64_SIZE(in_size))
yading@11:         return NULL;
yading@11:     ret = dst = out;
yading@11:     while (bytes_remaining > 3) {
yading@11:         i_bits = AV_RB32(in);
yading@11:         in += 3; bytes_remaining -= 3;
yading@11:         *dst++ = b64[ i_bits>>26        ];
yading@11:         *dst++ = b64[(i_bits>>20) & 0x3F];
yading@11:         *dst++ = b64[(i_bits>>14) & 0x3F];
yading@11:         *dst++ = b64[(i_bits>>8 ) & 0x3F];
yading@11:     }
yading@11:     i_bits = 0;
yading@11:     while (bytes_remaining) {
yading@11:         i_bits = (i_bits << 8) + *in++;
yading@11:         bytes_remaining--;
yading@11:         i_shift += 8;
yading@11:     }
yading@11:     while (i_shift > 0) {
yading@11:         *dst++ = b64[(i_bits << 6 >> i_shift) & 0x3f];
yading@11:         i_shift -= 6;
yading@11:     }
yading@11:     while ((dst - ret) & 3)
yading@11:         *dst++ = '=';
yading@11:     *dst = '\0';
yading@11: 
yading@11:     return ret;
yading@11: }
yading@11: 
yading@11: #ifdef TEST
yading@11: // LCOV_EXCL_START
yading@11: 
yading@11: #define MAX_DATA_SIZE    1024
yading@11: #define MAX_ENCODED_SIZE 2048
yading@11: 
yading@11: static int test_encode_decode(const uint8_t *data, unsigned int data_size,
yading@11:                               const char *encoded_ref)
yading@11: {
yading@11:     char  encoded[MAX_ENCODED_SIZE];
yading@11:     uint8_t data2[MAX_DATA_SIZE];
yading@11:     int data2_size, max_data2_size = MAX_DATA_SIZE;
yading@11: 
yading@11:     if (!av_base64_encode(encoded, MAX_ENCODED_SIZE, data, data_size)) {
yading@11:         printf("Failed: cannot encode the input data\n");
yading@11:         return 1;
yading@11:     }
yading@11:     if (encoded_ref && strcmp(encoded, encoded_ref)) {
yading@11:         printf("Failed: encoded string differs from reference\n"
yading@11:                "Encoded:\n%s\nReference:\n%s\n", encoded, encoded_ref);
yading@11:         return 1;
yading@11:     }
yading@11: 
yading@11:     if ((data2_size = av_base64_decode(data2, encoded, max_data2_size)) != data_size) {
yading@11:         printf("Failed: cannot decode the encoded string\n"
yading@11:                "Encoded:\n%s\n", encoded);
yading@11:         return 1;
yading@11:     }
yading@11:     if ((data2_size = av_base64_decode(data2, encoded, data_size)) != data_size) {
yading@11:         printf("Failed: cannot decode with minimal buffer\n"
yading@11:                "Encoded:\n%s\n", encoded);
yading@11:         return 1;
yading@11:     }
yading@11:     if (memcmp(data2, data, data_size)) {
yading@11:         printf("Failed: encoded/decoded data differs from original data\n");
yading@11:         return 1;
yading@11:     }
yading@11:     if (av_base64_decode(NULL, encoded, 0) != 0) {
yading@11:         printf("Failed: decode to NULL buffer\n");
yading@11:         return 1;
yading@11:     }
yading@11:     if (strlen(encoded)) {
yading@11:         char *end = strchr(encoded, '=');
yading@11:         if (!end)
yading@11:             end = encoded + strlen(encoded) - 1;
yading@11:         *end = '%';
yading@11:         if (av_base64_decode(NULL, encoded, 0) >= 0) {
yading@11:             printf("Failed: error detection\n");
yading@11:             return 1;
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     printf("Passed!\n");
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: int main(int argc, char ** argv)
yading@11: {
yading@11:     int i, error_count = 0;
yading@11:     struct test {
yading@11:         const uint8_t *data;
yading@11:         const char *encoded_ref;
yading@11:     } tests[] = {
yading@11:         { "",        ""},
yading@11:         { "1",       "MQ=="},
yading@11:         { "22",      "MjI="},
yading@11:         { "333",     "MzMz"},
yading@11:         { "4444",    "NDQ0NA=="},
yading@11:         { "55555",   "NTU1NTU="},
yading@11:         { "666666",  "NjY2NjY2"},
yading@11:         { "abc:def", "YWJjOmRlZg=="},
yading@11:     };
yading@11:     char in[1024], out[2048];
yading@11: 
yading@11:     printf("Encoding/decoding tests\n");
yading@11:     for (i = 0; i < FF_ARRAY_ELEMS(tests); i++)
yading@11:         error_count += test_encode_decode(tests[i].data, strlen(tests[i].data), tests[i].encoded_ref);
yading@11: 
yading@11:     if (argc>1 && !strcmp(argv[1], "-t")) {
yading@11:         memset(in, 123, sizeof(in));
yading@11:         for(i=0; i<10000; i++){
yading@11:             START_TIMER
yading@11:             av_base64_encode(out, sizeof(out), in, sizeof(in));
yading@11:             STOP_TIMER("encode")
yading@11:         }
yading@11:         for(i=0; i<10000; i++){
yading@11:             START_TIMER
yading@11:             av_base64_decode(in, out, sizeof(in));
yading@11:             STOP_TIMER("decode")
yading@11:         }
yading@11: 
yading@11:         for(i=0; i<10000; i++){
yading@11:             START_TIMER
yading@11:             av_base64_decode(NULL, out, 0);
yading@11:             STOP_TIMER("syntax check")
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     return error_count;
yading@11: }
yading@11: 
yading@11: // LCOV_EXCL_STOP
yading@11: #endif