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comparison libtomcrypt/src/pk/ecc/ecc_verify_hash.c @ 1710:1ff2a1034c52

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Fix whitespace changes vs upstream libtomcrypt
author Matt Johnston <matt@ucc.asn.au>
date Wed, 10 Jun 2020 23:01:33 +0800
parents 8305ebe45940
children
comparison
equal deleted inserted replaced
1709:04155ce30759 1710:1ff2a1034c52
12 #if defined(LTC_MECC) && defined(LTC_DER) 12 #if defined(LTC_MECC) && defined(LTC_DER)
13 13
14 /** 14 /**
15 @file ecc_verify_hash.c 15 @file ecc_verify_hash.c
16 ECC Crypto, Tom St Denis 16 ECC Crypto, Tom St Denis
17 */ 17 */
18 18
19 static int _ecc_verify_hash(const unsigned char *sig, unsigned long siglen, 19 static int _ecc_verify_hash(const unsigned char *sig, unsigned long siglen,
20 const unsigned char *hash, unsigned long hashlen, 20 const unsigned char *hash, unsigned long hashlen,
21 int *stat, ecc_key *key, int sigformat) 21 int *stat, ecc_key *key, int sigformat)
22 { 22 {
23 ecc_point *mG, *mQ; 23 ecc_point *mG, *mQ;
24 void *r, *s, *v, *w, *u1, *u2, *e, *p, *m; 24 void *r, *s, *v, *w, *u1, *u2, *e, *p, *m;
25 void *mp; 25 void *mp;
64 if ((err = mp_read_unsigned_bin(r, (unsigned char *)sig, i)) != CRYPT_OK) { goto error; } 64 if ((err = mp_read_unsigned_bin(r, (unsigned char *)sig, i)) != CRYPT_OK) { goto error; }
65 if ((err = mp_read_unsigned_bin(s, (unsigned char *)sig+i, i)) != CRYPT_OK) { goto error; } 65 if ((err = mp_read_unsigned_bin(s, (unsigned char *)sig+i, i)) != CRYPT_OK) { goto error; }
66 } 66 }
67 else { 67 else {
68 /* ASN.1 format */ 68 /* ASN.1 format */
69 if ((err = der_decode_sequence_multi(sig, siglen, 69 if ((err = der_decode_sequence_multi(sig, siglen,
70 LTC_ASN1_INTEGER, 1UL, r, 70 LTC_ASN1_INTEGER, 1UL, r,
71 LTC_ASN1_INTEGER, 1UL, s, 71 LTC_ASN1_INTEGER, 1UL, s,
72 LTC_ASN1_EOL, 0UL, NULL)) != CRYPT_OK) { goto error; } 72 LTC_ASN1_EOL, 0UL, NULL)) != CRYPT_OK) { goto error; }
73 } 73 }
74 74
75 /* get the order */ 75 /* get the order */
76 if ((err = mp_read_radix(p, (char *)key->dp->order, 16)) != CRYPT_OK) { goto error; } 76 if ((err = mp_read_radix(p, (char *)key->dp->order, 16)) != CRYPT_OK) { goto error; }
123 123
124 /* compute u1*mG + u2*mQ = mG */ 124 /* compute u1*mG + u2*mQ = mG */
125 if (ltc_mp.ecc_mul2add == NULL) { 125 if (ltc_mp.ecc_mul2add == NULL) {
126 if ((err = ltc_mp.ecc_ptmul(u1, mG, mG, m, 0)) != CRYPT_OK) { goto error; } 126 if ((err = ltc_mp.ecc_ptmul(u1, mG, mG, m, 0)) != CRYPT_OK) { goto error; }
127 if ((err = ltc_mp.ecc_ptmul(u2, mQ, mQ, m, 0)) != CRYPT_OK) { goto error; } 127 if ((err = ltc_mp.ecc_ptmul(u2, mQ, mQ, m, 0)) != CRYPT_OK) { goto error; }
128 128
129 /* find the montgomery mp */ 129 /* find the montgomery mp */
130 if ((err = mp_montgomery_setup(m, &mp)) != CRYPT_OK) { goto error; } 130 if ((err = mp_montgomery_setup(m, &mp)) != CRYPT_OK) { goto error; }
131 131
132 /* add them */ 132 /* add them */
133 if ((err = ltc_mp.ecc_ptadd(mQ, mG, mG, m, mp)) != CRYPT_OK) { goto error; } 133 if ((err = ltc_mp.ecc_ptadd(mQ, mG, mG, m, mp)) != CRYPT_OK) { goto error; }
134 134
135 /* reduce */ 135 /* reduce */
136 if ((err = ltc_mp.ecc_map(mG, m, mp)) != CRYPT_OK) { goto error; } 136 if ((err = ltc_mp.ecc_map(mG, m, mp)) != CRYPT_OK) { goto error; }
137 } else { 137 } else {
138 /* use Shamir's trick to compute u1*mG + u2*mQ using half of the doubles */ 138 /* use Shamir's trick to compute u1*mG + u2*mQ using half of the doubles */
139 if ((err = ltc_mp.ecc_mul2add(mG, u1, mQ, u2, mG, m)) != CRYPT_OK) { goto error; } 139 if ((err = ltc_mp.ecc_mul2add(mG, u1, mQ, u2, mG, m)) != CRYPT_OK) { goto error; }
151 err = CRYPT_OK; 151 err = CRYPT_OK;
152 error: 152 error:
153 ltc_ecc_del_point(mG); 153 ltc_ecc_del_point(mG);
154 ltc_ecc_del_point(mQ); 154 ltc_ecc_del_point(mQ);
155 mp_clear_multi(r, s, v, w, u1, u2, p, e, m, NULL); 155 mp_clear_multi(r, s, v, w, u1, u2, p, e, m, NULL);
156 if (mp != NULL) { 156 if (mp != NULL) {
157 mp_montgomery_free(mp); 157 mp_montgomery_free(mp);
158 } 158 }
159 return err; 159 return err;
160 } 160 }
161 161