0.96 release of LibTomCrypt

--HG--
branch : libtomcrypt-orig
extra : convert_revision : a1c3f430d3257b3ce499c24261ad1366b200f2ce

base64_encode.c

@@ -0,0 +1,63 @@
+/* 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
+