Mercurial > dropbear
diff src/misc/base64/base64_encode.c @ 192:9cc34777b479 libtomcrypt
propagate from branch 'au.asn.ucc.matt.ltc-orig' (head 9ba8f01f44320e9cb9f19881105ae84f84a43ea9)
to branch 'au.asn.ucc.matt.dropbear.ltc' (head dbf51c569bc34956ad948e4cc87a0eeb2170b768)
author | Matt Johnston <matt@ucc.asn.au> |
---|---|
date | Sun, 08 May 2005 06:36:47 +0000 |
parents | 1c15b283127b |
children | 39d5d58461d6 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/misc/base64/base64_encode.c Sun May 08 06:36:47 2005 +0000 @@ -0,0 +1,76 @@ +/* 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, [email protected], http://libtomcrypt.org + */ +#include "tomcrypt.h" + +/** + @file base64_encode.c + Compliant base64 encoder donated by Wayne Scott ([email protected]) +*/ + + +#ifdef BASE64 + +static const char *codes = +"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; + +/** + base64 Encode a buffer (NUL terminated) + @param in The input buffer to encode + @param inlen The length of the input buffer + @param out [out] The destination of the base64 encoded data + @param outlen [in/out] The max size and resulting size + @return CRYPT_OK if successful +*/ +int base64_encode(const unsigned char *in, unsigned long inlen, + unsigned char *out, unsigned long *outlen) +{ + unsigned long i, len2, leven; + unsigned char *p; + + LTC_ARGCHK(in != NULL); + LTC_ARGCHK(out != NULL); + LTC_ARGCHK(outlen != NULL); + + /* valid output size ? */ + len2 = 4 * ((inlen + 2) / 3); + if (*outlen < len2 + 1) { + return CRYPT_BUFFER_OVERFLOW; + } + p = out; + leven = 3*(inlen / 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 < inlen) { + unsigned a = in[0]; + unsigned b = (i+1 < inlen) ? in[1] : 0; + + *p++ = codes[(a >> 2) & 0x3F]; + *p++ = codes[(((a & 3) << 4) + (b >> 4)) & 0x3F]; + *p++ = (i+1 < inlen) ? codes[(((b & 0xf) << 2)) & 0x3F] : '='; + *p++ = '='; + } + + /* append a NULL byte */ + *p = '\0'; + + /* return ok */ + *outlen = p - out; + return CRYPT_OK; +} + +#endif +