ffmpeg/libavutil/base64.c

282 lines
8.3 KiB
C

/*
* 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"
#include "timer.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 ? AVERROR_INVALIDDATA : 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
#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")
}
}
if (error_count)
printf("Error Count: %d.\n", error_count);
return !!error_count;
}
// LCOV_EXCL_STOP
#endif