Mercurial > dropbear
diff src/mac/pmac/pmac_process.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/mac/pmac/pmac_process.c Sun May 08 06:36:47 2005 +0000 @@ -0,0 +1,92 @@ +/* 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 pmac_process.c + PMAC implementation, process data, by Tom St Denis +*/ + + +#ifdef PMAC + +/** + Process data in a PMAC stream + @param pmac The PMAC state + @param in The data to send through PMAC + @param inlen The length of the data to send through PMAC + @return CRYPT_OK if successful +*/ +int pmac_process(pmac_state *pmac, const unsigned char *in, unsigned long inlen) +{ + int err, n; + unsigned long x; + unsigned char Z[MAXBLOCKSIZE]; + + LTC_ARGCHK(pmac != NULL); + LTC_ARGCHK(in != NULL); + if ((err = cipher_is_valid(pmac->cipher_idx)) != CRYPT_OK) { + return err; + } + + if ((pmac->buflen > (int)sizeof(pmac->block)) || (pmac->buflen < 0) || + (pmac->block_len > (int)sizeof(pmac->block)) || (pmac->buflen > pmac->block_len)) { + return CRYPT_INVALID_ARG; + } + +#ifdef LTC_FAST + if (pmac->buflen == 0 && inlen > 16) { + unsigned long y; + for (x = 0; x < (inlen - 16); x += 16) { + pmac_shift_xor(pmac); + for (y = 0; y < 16; y += sizeof(LTC_FAST_TYPE)) { + *((LTC_FAST_TYPE*)(&Z[y])) = *((LTC_FAST_TYPE*)(&in[y])) ^ *((LTC_FAST_TYPE*)(&pmac->Li[y])); + } + cipher_descriptor[pmac->cipher_idx].ecb_encrypt(Z, Z, &pmac->key); + for (y = 0; y < 16; y += sizeof(LTC_FAST_TYPE)) { + *((LTC_FAST_TYPE*)(&pmac->checksum[y])) ^= *((LTC_FAST_TYPE*)(&Z[y])); + } + in += 16; + } + inlen -= x; + } +#endif + + while (inlen != 0) { + /* ok if the block is full we xor in prev, encrypt and replace prev */ + if (pmac->buflen == pmac->block_len) { + pmac_shift_xor(pmac); + for (x = 0; x < (unsigned long)pmac->block_len; x++) { + Z[x] = pmac->Li[x] ^ pmac->block[x]; + } + cipher_descriptor[pmac->cipher_idx].ecb_encrypt(Z, Z, &pmac->key); + for (x = 0; x < (unsigned long)pmac->block_len; x++) { + pmac->checksum[x] ^= Z[x]; + } + pmac->buflen = 0; + } + + /* add bytes */ + n = MIN(inlen, (unsigned long)(pmac->block_len - pmac->buflen)); + XMEMCPY(pmac->block + pmac->buflen, in, n); + pmac->buflen += n; + inlen -= n; + in += n; + } + +#ifdef LTC_CLEAN_STACK + zeromem(Z, sizeof(Z)); +#endif + + return CRYPT_OK; +} + +#endif