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/* LibTomCrypt, modular cryptographic library -- Tom St Denis
*
* LibTomCrypt is a library that provides various cryptographic
* algorithms in a highly modular and flexible manner.
*
* The library is free for all purposes without any express
* guarantee it works.
*
* Tom St Denis, tomstdenis@iahu.ca, http://libtomcrypt.org
*/
/* compliant base64 code donated by Wayne Scott (wscott@bitmover.com) */
#include "mycrypt.h"
#ifdef BASE64
static const char *codes =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
int base64_encode(const unsigned char *in, unsigned long len,
unsigned char *out, unsigned long *outlen)
{
unsigned long i, len2, leven;
unsigned char *p;
_ARGCHK(in != NULL);
_ARGCHK(out != NULL);
_ARGCHK(outlen != NULL);
/* valid output size ? */
len2 = 4 * ((len + 2) / 3);
if (*outlen < len2 + 1) {
return CRYPT_BUFFER_OVERFLOW;
}
p = out;
leven = 3*(len / 3);
for (i = 0; i < leven; i += 3) {
*p++ = codes[(in[0] >> 2) & 0x3F];
*p++ = codes[(((in[0] & 3) << 4) + (in[1] >> 4)) & 0x3F];
*p++ = codes[(((in[1] & 0xf) << 2) + (in[2] >> 6)) & 0x3F];
*p++ = codes[in[2] & 0x3F];
in += 3;
}
/* Pad it if necessary... */
if (i < len) {
unsigned a = in[0];
unsigned b = (i+1 < len) ? in[1] : 0;
*p++ = codes[(a >> 2) & 0x3F];
*p++ = codes[(((a & 3) << 4) + (b >> 4)) & 0x3F];
*p++ = (i+1 < len) ? codes[(((b & 0xf) << 2)) & 0x3F] : '=';
*p++ = '=';
}
/* append a NULL byte */
*p = '\0';
/* return ok */
*outlen = p - out;
return CRYPT_OK;
}
#endif
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