blob: 3baab3b889f89d5d9b4aa14d30de75aecee97f43 [file] [log] [blame]
/*
* This code originally came from here
*
* http://base64.sourceforge.net/b64.c
*
* with the following license:
*
* LICENCE: Copyright (c) 2001 Bob Trower, Trantor Standard Systems Inc.
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated
* documentation files (the "Software"), to deal in the
* Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute,
* sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall
* be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
* KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
* WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
* PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS
* OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* VERSION HISTORY:
* Bob Trower 08/04/01 -- Create Version 0.00.00B
*
* I cleaned it up quite a bit to match the (linux kernel) style of the rest
* of libwebsockets; this version is under LGPL2 like the rest of libwebsockets
* since he explictly allows sublicensing, but I give the URL above so you can
* get the original with Bob's super-liberal terms directly if you prefer.
*/
#include <stdio.h>
#include <string.h>
#include <private-libwebsockets.h>
static const char encode[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
"abcdefghijklmnopqrstuvwxyz0123456789+/";
static const char decode[] = "|$$$}rstuvwxyz{$$$$$$$>?@ABCDEFGHIJKLMNOPQRSTUVW"
"$$$$$$XYZ[\\]^_`abcdefghijklmnopq";
int
lws_b64_encode_string(const char *in, int in_len, char *out, int out_size)
{
unsigned char triple[3];
int i;
int len;
int line = 0;
int done = 0;
while (in_len) {
len = 0;
for (i = 0; i < 3; i++) {
if (in_len) {
triple[i] = *in++;
len++;
in_len--;
} else
triple[i] = 0;
}
if (!len)
continue;
if (done + 4 >= out_size)
return -1;
*out++ = encode[triple[0] >> 2];
*out++ = encode[((triple[0] & 0x03) << 4) |
((triple[1] & 0xf0) >> 4)];
*out++ = (len > 1 ? encode[((triple[1] & 0x0f) << 2) |
((triple[2] & 0xc0) >> 6)] : '=');
*out++ = (len > 2 ? encode[triple[2] & 0x3f] : '=');
done += 4;
line += 4;
}
if (done + 1 >= out_size)
return -1;
*out++ = '\0';
return done;
}
/*
* returns length of decoded string in out, or -1 if out was too small
* according to out_size
*/
int
lws_b64_decode_string(const char *in, char *out, int out_size)
{
int len;
int i;
int done = 0;
unsigned char v;
unsigned char quad[4];
while (*in) {
len = 0;
for (i = 0; i < 4 && *in; i++) {
v = 0;
while (*in && !v) {
v = *in++;
v = (v < 43 || v > 122) ? 0 : decode[v - 43];
if (v)
v = (v == '$') ? 0 : v - 61;
if (*in) {
len++;
if (v)
quad[i] = v - 1;
} else
quad[i] = 0;
}
}
if (!len)
continue;
if (out_size < (done + len - 1))
/* out buffer is too small */
return -1;
if (len >= 2)
*out++ = quad[0] << 2 | quad[1] >> 4;
if (len >= 3)
*out++ = quad[1] << 4 | quad[2] >> 2;
if (len >= 4)
*out++ = ((quad[2] << 6) & 0xc0) | quad[3];
done += len - 1;
}
if (done + 1 >= out_size)
return -1;
*out++ = '\0';
return done;
}
int
lws_b64_selftest(void)
{
char buf[64];
int n;
int test;
static const char * const plaintext[] = {
"sanity check base 64"
};
static const char * const coded[] = {
"c2FuaXR5IGNoZWNrIGJhc2UgNjQ="
};
for (test = 0; test < sizeof plaintext / sizeof(plaintext[0]); test++) {
buf[sizeof(buf) - 1] = '\0';
n = lws_b64_encode_string(plaintext[test],
strlen(plaintext[test]), buf, sizeof buf);
if (n != strlen(coded[test]) || strcmp(buf, coded[test])) {
lwsl_err("Failed lws_b64 encode selftest "
"%d result '%s' %d\n", test, buf, n);
return -1;
}
buf[sizeof(buf) - 1] = '\0';
n = lws_b64_decode_string(coded[test], buf, sizeof buf);
if (n != strlen(plaintext[test]) ||
strcmp(buf, plaintext[test])) {
lwsl_err("Failed lws_b64 decode selftest "
"%d result '%s' %d\n", test, buf, n);
return -1;
}
}
return 0;
}