X-Git-Url: https://pd.if.org/git/?a=blobdiff_plain;f=libtomcrypt%2Fsrc%2Fhashes%2Fchc%2Fchc.c;fp=libtomcrypt%2Fsrc%2Fhashes%2Fchc%2Fchc.c;h=0861a88a3eaf1e6f2f0c6791cd3f09113f143dff;hb=66bc25938679f1d6a1d1200f329093d82a5e99b4;hp=0000000000000000000000000000000000000000;hpb=a52ee0733f420ca20224049260d6fc5cf7d8f621;p=zpackage diff --git a/libtomcrypt/src/hashes/chc/chc.c b/libtomcrypt/src/hashes/chc/chc.c new file mode 100644 index 0000000..0861a88 --- /dev/null +++ b/libtomcrypt/src/hashes/chc/chc.c @@ -0,0 +1,306 @@ +/* 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 chc.c + CHC support. (Tom St Denis) +*/ + +#ifdef LTC_CHC_HASH + +#define UNDEFED_HASH -17 + +/* chc settings */ +static int cipher_idx=UNDEFED_HASH, /* which cipher */ + cipher_blocksize; /* blocksize of cipher */ + + +const struct ltc_hash_descriptor chc_desc = { + "chc_hash", 12, 0, 0, { 0 }, 0, + &chc_init, + &chc_process, + &chc_done, + &chc_test, + NULL +}; + +/** + Initialize the CHC state with a given cipher + @param cipher The index of the cipher you wish to bind + @return CRYPT_OK if successful +*/ +int chc_register(int cipher) +{ + int err, kl, idx; + + if ((err = cipher_is_valid(cipher)) != CRYPT_OK) { + return err; + } + + /* will it be valid? */ + kl = cipher_descriptor[cipher].block_length; + + /* must be >64 bit block */ + if (kl <= 8) { + return CRYPT_INVALID_CIPHER; + } + + /* can we use the ideal keysize? */ + if ((err = cipher_descriptor[cipher].keysize(&kl)) != CRYPT_OK) { + return err; + } + /* we require that key size == block size be a valid choice */ + if (kl != cipher_descriptor[cipher].block_length) { + return CRYPT_INVALID_CIPHER; + } + + /* determine if chc_hash has been register_hash'ed already */ + if ((err = hash_is_valid(idx = find_hash("chc_hash"))) != CRYPT_OK) { + return err; + } + + /* store into descriptor */ + hash_descriptor[idx].hashsize = + hash_descriptor[idx].blocksize = cipher_descriptor[cipher].block_length; + + /* store the idx and block size */ + cipher_idx = cipher; + cipher_blocksize = cipher_descriptor[cipher].block_length; + return CRYPT_OK; +} + +/** + Initialize the hash state + @param md The hash state you wish to initialize + @return CRYPT_OK if successful +*/ +int chc_init(hash_state *md) +{ + symmetric_key *key; + unsigned char buf[MAXBLOCKSIZE]; + int err; + + LTC_ARGCHK(md != NULL); + + /* is the cipher valid? */ + if ((err = cipher_is_valid(cipher_idx)) != CRYPT_OK) { + return err; + } + + if (cipher_blocksize != cipher_descriptor[cipher_idx].block_length) { + return CRYPT_INVALID_CIPHER; + } + + if ((key = XMALLOC(sizeof(*key))) == NULL) { + return CRYPT_MEM; + } + + /* zero key and what not */ + zeromem(buf, cipher_blocksize); + if ((err = cipher_descriptor[cipher_idx].setup(buf, cipher_blocksize, 0, key)) != CRYPT_OK) { + XFREE(key); + return err; + } + + /* encrypt zero block */ + cipher_descriptor[cipher_idx].ecb_encrypt(buf, md->chc.state, key); + + /* zero other members */ + md->chc.length = 0; + md->chc.curlen = 0; + zeromem(md->chc.buf, sizeof(md->chc.buf)); + XFREE(key); + return CRYPT_OK; +} + +/* + key <= state + T0,T1 <= block + T0 <= encrypt T0 + state <= state xor T0 xor T1 +*/ +static int chc_compress(hash_state *md, unsigned char *buf) +{ + unsigned char T[2][MAXBLOCKSIZE]; + symmetric_key *key; + int err, x; + + if ((key = XMALLOC(sizeof(*key))) == NULL) { + return CRYPT_MEM; + } + if ((err = cipher_descriptor[cipher_idx].setup(md->chc.state, cipher_blocksize, 0, key)) != CRYPT_OK) { + XFREE(key); + return err; + } + XMEMCPY(T[1], buf, cipher_blocksize); + cipher_descriptor[cipher_idx].ecb_encrypt(buf, T[0], key); + for (x = 0; x < cipher_blocksize; x++) { + md->chc.state[x] ^= T[0][x] ^ T[1][x]; + } +#ifdef LTC_CLEAN_STACK + zeromem(T, sizeof(T)); + zeromem(key, sizeof(*key)); +#endif + XFREE(key); + return CRYPT_OK; +} + +/** + Function for processing blocks + @param md The hash state + @param buf The data to hash + @param len The length of the data (octets) + @return CRYPT_OK if successful +*/ +static int _chc_process(hash_state * md, const unsigned char *buf, unsigned long len); +static HASH_PROCESS(_chc_process, chc_compress, chc, (unsigned long)cipher_blocksize) + +/** + Process a block of memory though the hash + @param md The hash state + @param in The data to hash + @param inlen The length of the data (octets) + @return CRYPT_OK if successful +*/ +int chc_process(hash_state * md, const unsigned char *in, unsigned long inlen) +{ + int err; + + LTC_ARGCHK(md != NULL); + LTC_ARGCHK(in != NULL); + + /* is the cipher valid? */ + if ((err = cipher_is_valid(cipher_idx)) != CRYPT_OK) { + return err; + } + if (cipher_blocksize != cipher_descriptor[cipher_idx].block_length) { + return CRYPT_INVALID_CIPHER; + } + + return _chc_process(md, in, inlen); +} + +/** + Terminate the hash to get the digest + @param md The hash state + @param out [out] The destination of the hash (length of the block size of the block cipher) + @return CRYPT_OK if successful +*/ +int chc_done(hash_state *md, unsigned char *out) +{ + int err; + + LTC_ARGCHK(md != NULL); + LTC_ARGCHK(out != NULL); + + /* is the cipher valid? */ + if ((err = cipher_is_valid(cipher_idx)) != CRYPT_OK) { + return err; + } + if (cipher_blocksize != cipher_descriptor[cipher_idx].block_length) { + return CRYPT_INVALID_CIPHER; + } + + if (md->chc.curlen >= sizeof(md->chc.buf)) { + return CRYPT_INVALID_ARG; + } + + /* increase the length of the message */ + md->chc.length += md->chc.curlen * 8; + + /* append the '1' bit */ + md->chc.buf[md->chc.curlen++] = (unsigned char)0x80; + + /* if the length is currently above l-8 bytes we append zeros + * then compress. Then we can fall back to padding zeros and length + * encoding like normal. + */ + if (md->chc.curlen > (unsigned long)(cipher_blocksize - 8)) { + while (md->chc.curlen < (unsigned long)cipher_blocksize) { + md->chc.buf[md->chc.curlen++] = (unsigned char)0; + } + chc_compress(md, md->chc.buf); + md->chc.curlen = 0; + } + + /* pad upto l-8 bytes of zeroes */ + while (md->chc.curlen < (unsigned long)(cipher_blocksize - 8)) { + md->chc.buf[md->chc.curlen++] = (unsigned char)0; + } + + /* store length */ + STORE64L(md->chc.length, md->chc.buf+(cipher_blocksize-8)); + chc_compress(md, md->chc.buf); + + /* copy output */ + XMEMCPY(out, md->chc.state, cipher_blocksize); + +#ifdef LTC_CLEAN_STACK + zeromem(md, sizeof(hash_state)); +#endif + return CRYPT_OK; +} + +/** + Self-test the hash + @return CRYPT_OK if successful, CRYPT_NOP if self-tests have been disabled +*/ +int chc_test(void) +{ +#ifndef LTC_TEST + return CRYPT_NOP; +#else + static const struct { + unsigned char *msg, + hash[MAXBLOCKSIZE]; + int len; + } tests[] = { +{ + (unsigned char *)"hello world", + { 0xcf, 0x57, 0x9d, 0xc3, 0x0a, 0x0e, 0xea, 0x61, + 0x0d, 0x54, 0x47, 0xc4, 0x3c, 0x06, 0xf5, 0x4e }, + 16 +} +}; + int i, oldhashidx, idx; + unsigned char tmp[MAXBLOCKSIZE]; + hash_state md; + + /* AES can be under rijndael or aes... try to find it */ + if ((idx = find_cipher("aes")) == -1) { + if ((idx = find_cipher("rijndael")) == -1) { + return CRYPT_NOP; + } + } + oldhashidx = cipher_idx; + chc_register(idx); + + for (i = 0; i < (int)(sizeof(tests)/sizeof(tests[0])); i++) { + chc_init(&md); + chc_process(&md, tests[i].msg, strlen((char *)tests[i].msg)); + chc_done(&md, tmp); + if (compare_testvector(tmp, tests[i].len, tests[i].hash, tests[i].len, "CHC", i)) { + return CRYPT_FAIL_TESTVECTOR; + } + } + if (oldhashidx != UNDEFED_HASH) { + chc_register(oldhashidx); + } + + return CRYPT_OK; +#endif +} + +#endif + +/* ref: $Format:%D$ */ +/* git commit: $Format:%H$ */ +/* commit time: $Format:%ai$ */