Mercurial > dropbear
view libtomcrypt/src/mac/xcbc/xcbc_init.c @ 1772:0cc85b4a4abb
Move fuzzer-kex initialisation into a constructor function
Hopefully this can avoid hitting AFL timeouts
https://github.com/google/oss-fuzz/pull/2474
author | Matt Johnston <matt@ucc.asn.au> |
---|---|
date | Thu, 29 Oct 2020 23:00:52 +0800 |
parents | 6dba84798cd5 |
children |
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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. */ #include "tomcrypt.h" /** @file xcbc_init.c XCBC Support, start an XCBC state */ #ifdef LTC_XCBC /** Initialize XCBC-MAC state @param xcbc [out] XCBC state to initialize @param cipher Index of cipher to use @param key [in] Secret key @param keylen Length of secret key in octets Return CRYPT_OK on success */ int xcbc_init(xcbc_state *xcbc, int cipher, const unsigned char *key, unsigned long keylen) { int x, y, err; symmetric_key *skey; unsigned long k1; LTC_ARGCHK(xcbc != NULL); LTC_ARGCHK(key != NULL); /* schedule the key */ if ((err = cipher_is_valid(cipher)) != CRYPT_OK) { return err; } #ifdef LTC_FAST if (cipher_descriptor[cipher].block_length % sizeof(LTC_FAST_TYPE)) { return CRYPT_INVALID_ARG; } #endif skey = NULL; /* are we in pure XCBC mode with three keys? */ if (keylen & LTC_XCBC_PURE) { keylen &= ~LTC_XCBC_PURE; if (keylen < 2UL*cipher_descriptor[cipher].block_length) { return CRYPT_INVALID_ARG; } k1 = keylen - 2*cipher_descriptor[cipher].block_length; XMEMCPY(xcbc->K[0], key, k1); XMEMCPY(xcbc->K[1], key+k1, cipher_descriptor[cipher].block_length); XMEMCPY(xcbc->K[2], key+k1 + cipher_descriptor[cipher].block_length, cipher_descriptor[cipher].block_length); } else { /* use the key expansion */ k1 = cipher_descriptor[cipher].block_length; /* schedule the user key */ skey = XCALLOC(1, sizeof(*skey)); if (skey == NULL) { return CRYPT_MEM; } if ((err = cipher_descriptor[cipher].setup(key, keylen, 0, skey)) != CRYPT_OK) { goto done; } /* make the three keys */ for (y = 0; y < 3; y++) { for (x = 0; x < cipher_descriptor[cipher].block_length; x++) { xcbc->K[y][x] = y + 1; } cipher_descriptor[cipher].ecb_encrypt(xcbc->K[y], xcbc->K[y], skey); } } /* setup K1 */ err = cipher_descriptor[cipher].setup(xcbc->K[0], k1, 0, &xcbc->key); /* setup struct */ zeromem(xcbc->IV, cipher_descriptor[cipher].block_length); xcbc->blocksize = cipher_descriptor[cipher].block_length; xcbc->cipher = cipher; xcbc->buflen = 0; done: cipher_descriptor[cipher].done(skey); if (skey != NULL) { #ifdef LTC_CLEAN_STACK zeromem(skey, sizeof(*skey)); #endif XFREE(skey); } return err; } #endif /* ref: $Format:%D$ */ /* git commit: $Format:%H$ */ /* commit time: $Format:%ai$ */