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-rw-r--r--src/pk/ecc/ecc_sys.c462
1 files changed, 0 insertions, 462 deletions
diff --git a/src/pk/ecc/ecc_sys.c b/src/pk/ecc/ecc_sys.c
deleted file mode 100644
index 65ead31..0000000
--- a/src/pk/ecc/ecc_sys.c
+++ /dev/null
@@ -1,462 +0,0 @@
-/* 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.org
- */
-
-/**
- @file ecc_sys.c
- ECC Crypto, Tom St Denis
-*/
-
-/**
- Encrypt a symmetric key with ECC
- @param in The symmetric key you want to encrypt
- @param inlen The length of the key to encrypt (octets)
- @param out [out] The destination for the ciphertext
- @param outlen [in/out] The max size and resulting size of the ciphertext
- @param prng An active PRNG state
- @param wprng The index of the PRNG you wish to use
- @param hash The index of the hash you want to use
- @param key The ECC key you want to encrypt to
- @return CRYPT_OK if successful
-*/
-int ecc_encrypt_key(const unsigned char *in, unsigned long inlen,
- unsigned char *out, unsigned long *outlen,
- prng_state *prng, int wprng, int hash,
- ecc_key *key)
-{
- unsigned char *pub_expt, *ecc_shared, *skey;
- ecc_key pubkey;
- unsigned long x, y, pubkeysize;
- int err;
-
- LTC_ARGCHK(in != NULL);
- LTC_ARGCHK(out != NULL);
- LTC_ARGCHK(outlen != NULL);
- LTC_ARGCHK(key != NULL);
-
- /* check that wprng/cipher/hash are not invalid */
- if ((err = prng_is_valid(wprng)) != CRYPT_OK) {
- return err;
- }
-
- if ((err = hash_is_valid(hash)) != CRYPT_OK) {
- return err;
- }
-
- if (inlen > hash_descriptor[hash].hashsize) {
- return CRYPT_INVALID_HASH;
- }
-
- /* make a random key and export the public copy */
- if ((err = ecc_make_key(prng, wprng, ecc_get_size(key), &pubkey)) != CRYPT_OK) {
- return err;
- }
-
- pub_expt = XMALLOC(ECC_BUF_SIZE);
- ecc_shared = XMALLOC(ECC_BUF_SIZE);
- skey = XMALLOC(MAXBLOCKSIZE);
- if (pub_expt == NULL || ecc_shared == NULL || skey == NULL) {
- if (pub_expt != NULL) {
- XFREE(pub_expt);
- }
- if (ecc_shared != NULL) {
- XFREE(ecc_shared);
- }
- if (skey != NULL) {
- XFREE(skey);
- }
- ecc_free(&pubkey);
- return CRYPT_MEM;
- }
-
- pubkeysize = ECC_BUF_SIZE;
- if ((err = ecc_export(pub_expt, &pubkeysize, PK_PUBLIC, &pubkey)) != CRYPT_OK) {
- ecc_free(&pubkey);
- goto LBL_ERR;
- }
-
- /* make random key */
- x = ECC_BUF_SIZE;
- if ((err = ecc_shared_secret(&pubkey, key, ecc_shared, &x)) != CRYPT_OK) {
- ecc_free(&pubkey);
- goto LBL_ERR;
- }
- ecc_free(&pubkey);
- y = MAXBLOCKSIZE;
- if ((err = hash_memory(hash, ecc_shared, x, skey, &y)) != CRYPT_OK) {
- goto LBL_ERR;
- }
-
- /* Encrypt key */
- for (x = 0; x < inlen; x++) {
- skey[x] ^= in[x];
- }
-
- err = der_encode_sequence_multi(out, outlen,
- LTC_ASN1_OBJECT_IDENTIFIER, hash_descriptor[hash].OIDlen, hash_descriptor[hash].OID,
- LTC_ASN1_OCTET_STRING, pubkeysize, pub_expt,
- LTC_ASN1_OCTET_STRING, inlen, skey,
- LTC_ASN1_EOL, 0UL, NULL);
-
-LBL_ERR:
-#ifdef LTC_CLEAN_STACK
- /* clean up */
- zeromem(pub_expt, ECC_BUF_SIZE);
- zeromem(ecc_shared, ECC_BUF_SIZE);
- zeromem(skey, MAXBLOCKSIZE);
-#endif
-
- XFREE(skey);
- XFREE(ecc_shared);
- XFREE(pub_expt);
-
- return err;
-}
-
-/**
- Decrypt an ECC encrypted key
- @param in The ciphertext
- @param inlen The length of the ciphertext (octets)
- @param out [out] The plaintext
- @param outlen [in/out] The max size and resulting size of the plaintext
- @param key The corresponding private ECC key
- @return CRYPT_OK if successful
-*/
-int ecc_decrypt_key(const unsigned char *in, unsigned long inlen,
- unsigned char *out, unsigned long *outlen,
- ecc_key *key)
-{
- unsigned char *ecc_shared, *skey, *pub_expt;
- unsigned long x, y, hashOID[32];
- int hash, err;
- ecc_key pubkey;
- ltc_asn1_list decode[3];
-
- LTC_ARGCHK(in != NULL);
- LTC_ARGCHK(out != NULL);
- LTC_ARGCHK(outlen != NULL);
- LTC_ARGCHK(key != NULL);
-
- /* right key type? */
- if (key->type != PK_PRIVATE) {
- return CRYPT_PK_NOT_PRIVATE;
- }
-
- /* decode to find out hash */
- LTC_SET_ASN1(decode, 0, LTC_ASN1_OBJECT_IDENTIFIER, hashOID, sizeof(hashOID)/sizeof(hashOID[0]));
-
- if ((err = der_decode_sequence(in, inlen, decode, 1)) != CRYPT_OK) {
- return err;
- }
- for (hash = 0; hash_descriptor[hash].name != NULL &&
- (hash_descriptor[hash].OIDlen != decode[0].size ||
- memcmp(hash_descriptor[hash].OID, hashOID, sizeof(unsigned long)*decode[0].size)); hash++);
-
- if (hash_descriptor[hash].name == NULL) {
- return CRYPT_INVALID_PACKET;
- }
-
- /* we now have the hash! */
-
- /* allocate memory */
- pub_expt = XMALLOC(ECC_BUF_SIZE);
- ecc_shared = XMALLOC(ECC_BUF_SIZE);
- skey = XMALLOC(MAXBLOCKSIZE);
- if (pub_expt == NULL || ecc_shared == NULL || skey == NULL) {
- if (pub_expt != NULL) {
- XFREE(pub_expt);
- }
- if (ecc_shared != NULL) {
- XFREE(ecc_shared);
- }
- if (skey != NULL) {
- XFREE(skey);
- }
- return CRYPT_MEM;
- }
- LTC_SET_ASN1(decode, 1, LTC_ASN1_OCTET_STRING, pub_expt, ECC_BUF_SIZE);
- LTC_SET_ASN1(decode, 2, LTC_ASN1_OCTET_STRING, skey, MAXBLOCKSIZE);
-
- /* read the structure in now */
- if ((err = der_decode_sequence(in, inlen, decode, 3)) != CRYPT_OK) {
- goto LBL_ERR;
- }
-
- /* import ECC key from packet */
- if ((err = ecc_import(decode[1].data, decode[1].size, &pubkey)) != CRYPT_OK) {
- goto LBL_ERR;
- }
-
- /* make shared key */
- x = ECC_BUF_SIZE;
- if ((err = ecc_shared_secret(key, &pubkey, ecc_shared, &x)) != CRYPT_OK) {
- ecc_free(&pubkey);
- goto LBL_ERR;
- }
- ecc_free(&pubkey);
-
- y = MAXBLOCKSIZE;
- if ((err = hash_memory(hash, ecc_shared, x, ecc_shared, &y)) != CRYPT_OK) {
- goto LBL_ERR;
- }
-
- /* ensure the hash of the shared secret is at least as big as the encrypt itself */
- if (decode[2].size > y) {
- err = CRYPT_INVALID_PACKET;
- goto LBL_ERR;
- }
-
- /* avoid buffer overflow */
- if (*outlen < decode[2].size) {
- err = CRYPT_BUFFER_OVERFLOW;
- goto LBL_ERR;
- }
-
- /* Decrypt the key */
- for (x = 0; x < decode[2].size; x++) {
- out[x] = skey[x] ^ ecc_shared[x];
- }
- *outlen = x;
-
- err = CRYPT_OK;
-LBL_ERR:
-#ifdef LTC_CLEAN_STACK
- zeromem(pub_expt, ECC_BUF_SIZE);
- zeromem(ecc_shared, ECC_BUF_SIZE);
- zeromem(skey, MAXBLOCKSIZE);
-#endif
-
- XFREE(pub_expt);
- XFREE(ecc_shared);
- XFREE(skey);
-
- return err;
-}
-
-/**
- Sign a message digest
- @param in The message digest to sign
- @param inlen The length of the digest
- @param out [out] The destination for the signature
- @param outlen [in/out] The max size and resulting size of the signature
- @param prng An active PRNG state
- @param wprng The index of the PRNG you wish to use
- @param key A private ECC key
- @return CRYPT_OK if successful
-*/
-int ecc_sign_hash(const unsigned char *in, unsigned long inlen,
- unsigned char *out, unsigned long *outlen,
- prng_state *prng, int wprng, ecc_key *key)
-{
- ecc_key pubkey;
- mp_int r, s, e, p;
- int err;
-
- LTC_ARGCHK(in != NULL);
- LTC_ARGCHK(out != NULL);
- LTC_ARGCHK(outlen != NULL);
- LTC_ARGCHK(key != NULL);
-
- /* is this a private key? */
- if (key->type != PK_PRIVATE) {
- return CRYPT_PK_NOT_PRIVATE;
- }
-
- /* is the IDX valid ? */
- if (is_valid_idx(key->idx) != 1) {
- return CRYPT_PK_INVALID_TYPE;
- }
-
- if ((err = prng_is_valid(wprng)) != CRYPT_OK) {
- return err;
- }
-
- /* get the hash and load it as a bignum into 'e' */
- /* init the bignums */
- if ((err = mp_init_multi(&r, &s, &p, &e, NULL)) != MP_OKAY) {
- ecc_free(&pubkey);
- err = mpi_to_ltc_error(err);
- goto LBL_ERR;
- }
- if ((err = mp_read_radix(&p, (char *)sets[key->idx].order, 64)) != MP_OKAY) { goto error; }
- if ((err = mp_read_unsigned_bin(&e, (unsigned char *)in, (int)inlen)) != MP_OKAY) { goto error; }
-
- /* make up a key and export the public copy */
- for (;;) {
- if ((err = ecc_make_key(prng, wprng, ecc_get_size(key), &pubkey)) != CRYPT_OK) {
- return err;
- }
-
- /* find r = x1 mod n */
- if ((err = mp_mod(&pubkey.pubkey.x, &p, &r)) != MP_OKAY) { goto error; }
-
- if (mp_iszero(&r)) {
- ecc_free(&pubkey);
- } else {
- /* find s = (e + xr)/k */
- if ((err = mp_invmod(&pubkey.k, &p, &pubkey.k)) != MP_OKAY) { goto error; } /* k = 1/k */
- if ((err = mp_mulmod(&key->k, &r, &p, &s)) != MP_OKAY) { goto error; } /* s = xr */
- if ((err = mp_addmod(&e, &s, &p, &s)) != MP_OKAY) { goto error; } /* s = e + xr */
- if ((err = mp_mulmod(&s, &pubkey.k, &p, &s)) != MP_OKAY) { goto error; } /* s = (e + xr)/k */
-
- if (mp_iszero(&s)) {
- ecc_free(&pubkey);
- } else {
- break;
- }
- }
- }
-
- /* store as SEQUENCE { r, s -- integer } */
- err = der_encode_sequence_multi(out, outlen,
- LTC_ASN1_INTEGER, 1UL, &r,
- LTC_ASN1_INTEGER, 1UL, &s,
- LTC_ASN1_EOL, 0UL, NULL);
- goto LBL_ERR;
-error:
- err = mpi_to_ltc_error(err);
-LBL_ERR:
- mp_clear_multi(&r, &s, &p, &e, NULL);
- ecc_free(&pubkey);
-
- return err;
-}
-
-/* verify
- *
- * w = s^-1 mod n
- * u1 = xw
- * u2 = rw
- * X = u1*G + u2*Q
- * v = X_x1 mod n
- * accept if v == r
- */
-
-/**
- Verify an ECC signature
- @param sig The signature to verify
- @param siglen The length of the signature (octets)
- @param hash The hash (message digest) that was signed
- @param hashlen The length of the hash (octets)
- @param stat Result of signature, 1==valid, 0==invalid
- @param key The corresponding public ECC key
- @return CRYPT_OK if successful (even if the signature is not valid)
-*/
-int ecc_verify_hash(const unsigned char *sig, unsigned long siglen,
- const unsigned char *hash, unsigned long hashlen,
- int *stat, ecc_key *key)
-{
- ecc_point *mG, *mQ;
- mp_int r, s, v, w, u1, u2, e, p, m;
- mp_digit mp;
- int err;
-
- LTC_ARGCHK(sig != NULL);
- LTC_ARGCHK(hash != NULL);
- LTC_ARGCHK(stat != NULL);
- LTC_ARGCHK(key != NULL);
-
- /* default to invalid signature */
- *stat = 0;
-
- /* is the IDX valid ? */
- if (is_valid_idx(key->idx) != 1) {
- return CRYPT_PK_INVALID_TYPE;
- }
-
- /* allocate ints */
- if ((err = mp_init_multi(&r, &s, &v, &w, &u1, &u2, &p, &e, &m, NULL)) != MP_OKAY) {
- return CRYPT_MEM;
- }
-
- /* allocate points */
- mG = new_point();
- mQ = new_point();
- if (mQ == NULL || mG == NULL) {
- err = CRYPT_MEM;
- goto done;
- }
-
- /* parse header */
- if ((err = der_decode_sequence_multi(sig, siglen,
- LTC_ASN1_INTEGER, 1UL, &r,
- LTC_ASN1_INTEGER, 1UL, &s,
- LTC_ASN1_EOL, 0UL, NULL)) != CRYPT_OK) {
- goto done;
- }
-
- /* get the order */
- if ((err = mp_read_radix(&p, (char *)sets[key->idx].order, 64)) != MP_OKAY) { goto error; }
-
- /* get the modulus */
- if ((err = mp_read_radix(&m, (char *)sets[key->idx].prime, 64)) != MP_OKAY) { goto error; }
-
- /* check for zero */
- if (mp_iszero(&r) || mp_iszero(&s) || mp_cmp(&r, &p) != MP_LT || mp_cmp(&s, &p) != MP_LT) {
- err = CRYPT_INVALID_PACKET;
- goto done;
- }
-
- /* read hash */
- if ((err = mp_read_unsigned_bin(&e, (unsigned char *)hash, (int)hashlen)) != MP_OKAY) { goto error; }
-
- /* w = s^-1 mod n */
- if ((err = mp_invmod(&s, &p, &w)) != MP_OKAY) { goto error; }
-
- /* u1 = ew */
- if ((err = mp_mulmod(&e, &w, &p, &u1)) != MP_OKAY) { goto error; }
-
- /* u2 = rw */
- if ((err = mp_mulmod(&r, &w, &p, &u2)) != MP_OKAY) { goto error; }
-
- /* find mG = u1*G */
- if ((err = mp_read_radix(&mG->x, (char *)sets[key->idx].Gx, 64)) != MP_OKAY) { goto error; }
- if ((err = mp_read_radix(&mG->y, (char *)sets[key->idx].Gy, 64)) != MP_OKAY) { goto error; }
- mp_set(&mG->z, 1);
- if ((err = ecc_mulmod(&u1, mG, mG, &m, 0)) != CRYPT_OK) { goto done; }
-
- /* find mQ = u2*Q */
- if ((err = mp_copy(&key->pubkey.x, &mQ->x)) != MP_OKAY) { goto error; }
- if ((err = mp_copy(&key->pubkey.y, &mQ->y)) != MP_OKAY) { goto error; }
- if ((err = mp_copy(&key->pubkey.z, &mQ->z)) != MP_OKAY) { goto error; }
- if ((err = ecc_mulmod(&u2, mQ, mQ, &m, 0)) != CRYPT_OK) { goto done; }
-
- /* find the montgomery mp */
- if ((err = mp_montgomery_setup(&m, &mp)) != MP_OKAY) { goto error; }
- /* add them */
- if ((err = add_point(mQ, mG, mG, &m, mp)) != CRYPT_OK) { goto done; }
-
- /* reduce */
- if ((err = ecc_map(mG, &m, mp)) != CRYPT_OK) { goto done; }
-
- /* v = X_x1 mod n */
- if ((err = mp_mod(&mG->x, &p, &v)) != CRYPT_OK) { goto done; }
-
- /* does v == r */
- if (mp_cmp(&v, &r) == MP_EQ) {
- *stat = 1;
- }
-
- /* clear up and return */
- err = CRYPT_OK;
- goto done;
-error:
- err = mpi_to_ltc_error(err);
-done:
- del_point(mG);
- del_point(mQ);
- mp_clear_multi(&r, &s, &v, &w, &u1, &u2, &p, &e, &m, NULL);
- return err;
-}
-
-
-/* $Source: /cvs/libtom/libtomcrypt/src/pk/ecc/ecc_sys.c,v $ */
-/* $Revision: 1.18 $ */
-/* $Date: 2005/06/14 20:47:55 $ */
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