Mercurial > dropbear
diff base64.c @ 0:d7da3b1e1540 libtomcrypt
put back the 0.95 makefile which was inadvertently merged over
author | Matt Johnston <matt@ucc.asn.au> |
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date | Mon, 31 May 2004 18:21:40 +0000 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/base64.c Mon May 31 18:21:40 2004 +0000 @@ -0,0 +1,121 @@ +/* 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 + */ +/* compliant base64 code donated by Wayne Scott ([email protected]) */ +#include "mycrypt.h" + +#ifdef BASE64 + +static const char *codes = +"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; + +static const unsigned char map[256] = { +255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, +255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, +255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, +255, 255, 255, 255, 255, 255, 255, 62, 255, 255, 255, 63, + 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 255, 255, +255, 254, 255, 255, 255, 0, 1, 2, 3, 4, 5, 6, + 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, + 19, 20, 21, 22, 23, 24, 25, 255, 255, 255, 255, 255, +255, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, + 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, + 49, 50, 51, 255, 255, 255, 255, 255, 255, 255, 255, 255, +255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, +255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, +255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, +255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, +255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, +255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, +255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, +255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, +255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, +255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, +255, 255, 255, 255 }; + +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; +} + +int base64_decode(const unsigned char *in, unsigned long len, + unsigned char *out, unsigned long *outlen) +{ + unsigned long t, x, y, z; + unsigned char c; + int g; + + _ARGCHK(in != NULL); + _ARGCHK(out != NULL); + _ARGCHK(outlen != NULL); + + g = 3; + for (x = y = z = t = 0; x < len; x++) { + c = map[in[x]&0xFF]; + if (c == 255) continue; + if (c == 254) { c = 0; g--; } + t = (t<<6)|c; + if (++y == 4) { + if (z + g > *outlen) { + return CRYPT_BUFFER_OVERFLOW; + } + out[z++] = (unsigned char)((t>>16)&255); + if (g > 1) out[z++] = (unsigned char)((t>>8)&255); + if (g > 2) out[z++] = (unsigned char)(t&255); + y = t = 0; + } + } + if (y != 0) { + return CRYPT_INVALID_PACKET; + } + *outlen = z; + return CRYPT_OK; +} + +#endif +