Mercurial > dropbear
view libtomcrypt/src/mac/pmac/pmac_process.c @ 397:2908122e9eed channel-fix
disapproval of revision '1250b8af44b62d8f4fe0f8d9fc7e7a1cc34e7e1c'
author | Matt Johnston <matt@ucc.asn.au> |
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date | Sat, 03 Feb 2007 08:10:09 +0000 |
parents | 1b9e69c058d2 |
children | 0cbe8f6dbf9e |
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/* 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 /* $Source: /cvs/libtom/libtomcrypt/src/mac/pmac/pmac_process.c,v $ */ /* $Revision: 1.5 $ */ /* $Date: 2005/05/05 14:35:59 $ */