diff options
Diffstat (limited to 'libtomcrypt/src/mac/xcbc/xcbc_process.c')
-rw-r--r-- | libtomcrypt/src/mac/xcbc/xcbc_process.c | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/libtomcrypt/src/mac/xcbc/xcbc_process.c b/libtomcrypt/src/mac/xcbc/xcbc_process.c new file mode 100644 index 0000000..4dd63b5 --- /dev/null +++ b/libtomcrypt/src/mac/xcbc/xcbc_process.c @@ -0,0 +1,75 @@ +/* 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@gmail.com, http://libtomcrypt.com + */ +#include "tomcrypt.h" + +/** + @file xcbc_process.c + XCBC Support, process blocks with XCBC +*/ + +#ifdef LTC_XCBC + +/** Process data through XCBC-MAC + @param xcbc The XCBC-MAC state + @param in Input data to process + @param inlen Length of input in octets + Return CRYPT_OK on success +*/ +int xcbc_process(xcbc_state *xcbc, const unsigned char *in, unsigned long inlen) +{ + int err; +#ifdef LTC_FAST + int x; +#endif + + LTC_ARGCHK(xcbc != NULL); + LTC_ARGCHK(in != NULL); + + /* check structure */ + if ((err = cipher_is_valid(xcbc->cipher)) != CRYPT_OK) { + return err; + } + + if ((xcbc->blocksize > cipher_descriptor[xcbc->cipher].block_length) || (xcbc->blocksize < 0) || + (xcbc->buflen > xcbc->blocksize) || (xcbc->buflen < 0)) { + return CRYPT_INVALID_ARG; + } + +#ifdef LTC_FAST + if (xcbc->buflen == 0) { + while (inlen > (unsigned long)xcbc->blocksize) { + for (x = 0; x < xcbc->blocksize; x += sizeof(LTC_FAST_TYPE)) { + *((LTC_FAST_TYPE*)&(xcbc->IV[x])) ^= *((LTC_FAST_TYPE*)&(in[x])); + } + cipher_descriptor[xcbc->cipher].ecb_encrypt(xcbc->IV, xcbc->IV, &xcbc->key); + in += xcbc->blocksize; + inlen -= xcbc->blocksize; + } + } +#endif + + while (inlen) { + if (xcbc->buflen == xcbc->blocksize) { + cipher_descriptor[xcbc->cipher].ecb_encrypt(xcbc->IV, xcbc->IV, &xcbc->key); + xcbc->buflen = 0; + } + xcbc->IV[xcbc->buflen++] ^= *in++; + --inlen; + } + return CRYPT_OK; +} + +#endif + +/* $Source: /cvs/libtom/libtomcrypt/src/mac/xcbc/xcbc_process.c,v $ */ +/* $Revision: 1.9 $ */ +/* $Date: 2006/11/09 22:43:52 $ */ + |