freeswitch/libs/libks/src/ks_base64.c
2017-03-22 17:42:49 -04:00

131 lines
3.1 KiB
C

/*
* Copyright (c) 2017 FreeSWITCH Solutions LLC
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* * Neither the name of the original author; nor the names of any contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
* OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <ks_base64.h>
static const char ks_b64_table[65] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
KS_DECLARE(ks_status_t) ks_b64_encode(unsigned char *in, ks_size_t ilen, unsigned char *out, ks_size_t olen)
{
int y = 0, bytes = 0;
size_t x = 0;
unsigned int b = 0, l = 0;
for (x = 0; x < ilen; x++) {
b = (b << 8) + in[x];
l += 8;
while (l >= 6) {
out[bytes++] = ks_b64_table[(b >> (l -= 6)) % 64];
if (bytes >= (int)olen - 1) {
goto end;
}
if (++y != 72) {
continue;
}
/* out[bytes++] = '\n'; */
y = 0;
}
}
if (l > 0) {
out[bytes++] = ks_b64_table[((b % 16) << (6 - l)) % 64];
}
if (l != 0) {
while (l < 6 && bytes < (int)olen - 1) {
out[bytes++] = '=', l += 2;
}
}
end:
out[bytes] = '\0';
return KS_STATUS_SUCCESS;
}
KS_DECLARE(ks_size_t) ks_b64_decode(char *in, char *out, ks_size_t olen)
{
char l64[256];
int b = 0, c, l = 0, i;
char *ip, *op = out;
size_t ol = 0;
for (i = 0; i < 256; i++) {
l64[i] = -1;
}
for (i = 0; i < 64; i++) {
l64[(int) ks_b64_table[i]] = (char) i;
}
for (ip = in; ip && *ip; ip++) {
c = l64[(int) *ip];
if (c == -1) {
continue;
}
b = (b << 6) + c;
l += 6;
while (l >= 8) {
op[ol++] = (char) ((b >> (l -= 8)) % 256);
if (ol >= olen - 2) {
goto end;
}
}
}
end:
op[ol++] = '\0';
return ol;
}
/* For Emacs:
* Local Variables:
* mode:c
* indent-tabs-mode:t
* tab-width:4
* c-basic-offset:4
* End:
* For VIM:
* vim:set softtabstop=4 shiftwidth=4 tabstop=4 noet:
*/