Xuyi Wang
/
wolfSSL
Important changes to repositories hosted on mbed.com
Mbed hosted mercurial repositories are deprecated and are due to be permanently deleted in July 2026.
To keep a copy of this software download the repository Zip archive or clone locally using Mercurial.
It is also possible to export all your personal repositories from the account settings page.
wolfcrypt/src/dsa.c@4:1b0d80432c79, 2016-04-28 (annotated)
- Committer:
- wolfSSL
- Date:
- Thu Apr 28 00:57:21 2016 +0000
- Revision:
- 4:1b0d80432c79
wolfSSL 3.9.0
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| wolfSSL | 4:1b0d80432c79 | 1 | /* dsa.c |
| wolfSSL | 4:1b0d80432c79 | 2 | * |
| wolfSSL | 4:1b0d80432c79 | 3 | * Copyright (C) 2006-2016 wolfSSL Inc. |
| wolfSSL | 4:1b0d80432c79 | 4 | * |
| wolfSSL | 4:1b0d80432c79 | 5 | * This file is part of wolfSSL. |
| wolfSSL | 4:1b0d80432c79 | 6 | * |
| wolfSSL | 4:1b0d80432c79 | 7 | * wolfSSL is free software; you can redistribute it and/or modify |
| wolfSSL | 4:1b0d80432c79 | 8 | * it under the terms of the GNU General Public License as published by |
| wolfSSL | 4:1b0d80432c79 | 9 | * the Free Software Foundation; either version 2 of the License, or |
| wolfSSL | 4:1b0d80432c79 | 10 | * (at your option) any later version. |
| wolfSSL | 4:1b0d80432c79 | 11 | * |
| wolfSSL | 4:1b0d80432c79 | 12 | * wolfSSL is distributed in the hope that it will be useful, |
| wolfSSL | 4:1b0d80432c79 | 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| wolfSSL | 4:1b0d80432c79 | 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| wolfSSL | 4:1b0d80432c79 | 15 | * GNU General Public License for more details. |
| wolfSSL | 4:1b0d80432c79 | 16 | * |
| wolfSSL | 4:1b0d80432c79 | 17 | * You should have received a copy of the GNU General Public License |
| wolfSSL | 4:1b0d80432c79 | 18 | * along with this program; if not, write to the Free Software |
| wolfSSL | 4:1b0d80432c79 | 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA |
| wolfSSL | 4:1b0d80432c79 | 20 | */ |
| wolfSSL | 4:1b0d80432c79 | 21 | |
| wolfSSL | 4:1b0d80432c79 | 22 | |
| wolfSSL | 4:1b0d80432c79 | 23 | #ifdef HAVE_CONFIG_H |
| wolfSSL | 4:1b0d80432c79 | 24 | #include <config.h> |
| wolfSSL | 4:1b0d80432c79 | 25 | #endif |
| wolfSSL | 4:1b0d80432c79 | 26 | |
| wolfSSL | 4:1b0d80432c79 | 27 | #include <wolfssl/wolfcrypt/settings.h> |
| wolfSSL | 4:1b0d80432c79 | 28 | |
| wolfSSL | 4:1b0d80432c79 | 29 | #ifndef NO_DSA |
| wolfSSL | 4:1b0d80432c79 | 30 | |
| wolfSSL | 4:1b0d80432c79 | 31 | #include <wolfssl/wolfcrypt/random.h> |
| wolfSSL | 4:1b0d80432c79 | 32 | #include <wolfssl/wolfcrypt/integer.h> |
| wolfSSL | 4:1b0d80432c79 | 33 | #include <wolfssl/wolfcrypt/error-crypt.h> |
| wolfSSL | 4:1b0d80432c79 | 34 | #include <wolfssl/wolfcrypt/logging.h> |
| wolfSSL | 4:1b0d80432c79 | 35 | #include <wolfssl/wolfcrypt/sha.h> |
| wolfSSL | 4:1b0d80432c79 | 36 | #include <wolfssl/wolfcrypt/dsa.h> |
| wolfSSL | 4:1b0d80432c79 | 37 | |
| wolfSSL | 4:1b0d80432c79 | 38 | |
| wolfSSL | 4:1b0d80432c79 | 39 | enum { |
| wolfSSL | 4:1b0d80432c79 | 40 | DSA_HALF_SIZE = 20, /* r and s size */ |
| wolfSSL | 4:1b0d80432c79 | 41 | DSA_SIG_SIZE = 40 /* signature size */ |
| wolfSSL | 4:1b0d80432c79 | 42 | }; |
| wolfSSL | 4:1b0d80432c79 | 43 | |
| wolfSSL | 4:1b0d80432c79 | 44 | |
| wolfSSL | 4:1b0d80432c79 | 45 | #ifndef WOLFSSL_HAVE_MIN |
| wolfSSL | 4:1b0d80432c79 | 46 | #define WOLFSSL_HAVE_MIN |
| wolfSSL | 4:1b0d80432c79 | 47 | |
| wolfSSL | 4:1b0d80432c79 | 48 | static INLINE word32 min(word32 a, word32 b) |
| wolfSSL | 4:1b0d80432c79 | 49 | { |
| wolfSSL | 4:1b0d80432c79 | 50 | return a > b ? b : a; |
| wolfSSL | 4:1b0d80432c79 | 51 | } |
| wolfSSL | 4:1b0d80432c79 | 52 | |
| wolfSSL | 4:1b0d80432c79 | 53 | #endif /* WOLFSSL_HAVE_MIN */ |
| wolfSSL | 4:1b0d80432c79 | 54 | |
| wolfSSL | 4:1b0d80432c79 | 55 | |
| wolfSSL | 4:1b0d80432c79 | 56 | void wc_InitDsaKey(DsaKey* key) |
| wolfSSL | 4:1b0d80432c79 | 57 | { |
| wolfSSL | 4:1b0d80432c79 | 58 | key->type = -1; /* haven't decided yet */ |
| wolfSSL | 4:1b0d80432c79 | 59 | |
| wolfSSL | 4:1b0d80432c79 | 60 | /* TomsFastMath doesn't use memory allocation */ |
| wolfSSL | 4:1b0d80432c79 | 61 | #ifndef USE_FAST_MATH |
| wolfSSL | 4:1b0d80432c79 | 62 | key->p.dp = 0; /* public alloc parts */ |
| wolfSSL | 4:1b0d80432c79 | 63 | key->q.dp = 0; |
| wolfSSL | 4:1b0d80432c79 | 64 | key->g.dp = 0; |
| wolfSSL | 4:1b0d80432c79 | 65 | key->y.dp = 0; |
| wolfSSL | 4:1b0d80432c79 | 66 | |
| wolfSSL | 4:1b0d80432c79 | 67 | key->x.dp = 0; /* private alloc parts */ |
| wolfSSL | 4:1b0d80432c79 | 68 | #endif |
| wolfSSL | 4:1b0d80432c79 | 69 | } |
| wolfSSL | 4:1b0d80432c79 | 70 | |
| wolfSSL | 4:1b0d80432c79 | 71 | |
| wolfSSL | 4:1b0d80432c79 | 72 | void wc_FreeDsaKey(DsaKey* key) |
| wolfSSL | 4:1b0d80432c79 | 73 | { |
| wolfSSL | 4:1b0d80432c79 | 74 | (void)key; |
| wolfSSL | 4:1b0d80432c79 | 75 | /* TomsFastMath doesn't use memory allocation */ |
| wolfSSL | 4:1b0d80432c79 | 76 | #ifndef USE_FAST_MATH |
| wolfSSL | 4:1b0d80432c79 | 77 | if (key->type == DSA_PRIVATE) |
| wolfSSL | 4:1b0d80432c79 | 78 | mp_clear(&key->x); |
| wolfSSL | 4:1b0d80432c79 | 79 | mp_clear(&key->y); |
| wolfSSL | 4:1b0d80432c79 | 80 | mp_clear(&key->g); |
| wolfSSL | 4:1b0d80432c79 | 81 | mp_clear(&key->q); |
| wolfSSL | 4:1b0d80432c79 | 82 | mp_clear(&key->p); |
| wolfSSL | 4:1b0d80432c79 | 83 | #endif |
| wolfSSL | 4:1b0d80432c79 | 84 | } |
| wolfSSL | 4:1b0d80432c79 | 85 | |
| wolfSSL | 4:1b0d80432c79 | 86 | #ifdef WOLFSSL_KEY_GEN |
| wolfSSL | 4:1b0d80432c79 | 87 | |
| wolfSSL | 4:1b0d80432c79 | 88 | int wc_MakeDsaKey(WC_RNG *rng, DsaKey *dsa) |
| wolfSSL | 4:1b0d80432c79 | 89 | { |
| wolfSSL | 4:1b0d80432c79 | 90 | unsigned char *buf; |
| wolfSSL | 4:1b0d80432c79 | 91 | int qsize, err; |
| wolfSSL | 4:1b0d80432c79 | 92 | |
| wolfSSL | 4:1b0d80432c79 | 93 | if (rng == NULL || dsa == NULL) |
| wolfSSL | 4:1b0d80432c79 | 94 | return BAD_FUNC_ARG; |
| wolfSSL | 4:1b0d80432c79 | 95 | |
| wolfSSL | 4:1b0d80432c79 | 96 | qsize = mp_unsigned_bin_size(&dsa->q); |
| wolfSSL | 4:1b0d80432c79 | 97 | if (qsize == 0) |
| wolfSSL | 4:1b0d80432c79 | 98 | return BAD_FUNC_ARG; |
| wolfSSL | 4:1b0d80432c79 | 99 | |
| wolfSSL | 4:1b0d80432c79 | 100 | /* allocate ram */ |
| wolfSSL | 4:1b0d80432c79 | 101 | buf = (unsigned char *)XMALLOC(qsize, NULL, |
| wolfSSL | 4:1b0d80432c79 | 102 | DYNAMIC_TYPE_TMP_BUFFER); |
| wolfSSL | 4:1b0d80432c79 | 103 | if (buf == NULL) |
| wolfSSL | 4:1b0d80432c79 | 104 | return MEMORY_E; |
| wolfSSL | 4:1b0d80432c79 | 105 | |
| wolfSSL | 4:1b0d80432c79 | 106 | if (mp_init(&dsa->x) != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 107 | XFREE(buf, NULL, DYNAMIC_TYPE_TMP_BUFFER); |
| wolfSSL | 4:1b0d80432c79 | 108 | return MP_INIT_E; |
| wolfSSL | 4:1b0d80432c79 | 109 | } |
| wolfSSL | 4:1b0d80432c79 | 110 | |
| wolfSSL | 4:1b0d80432c79 | 111 | do { |
| wolfSSL | 4:1b0d80432c79 | 112 | /* make a random exponent mod q */ |
| wolfSSL | 4:1b0d80432c79 | 113 | err = wc_RNG_GenerateBlock(rng, buf, qsize); |
| wolfSSL | 4:1b0d80432c79 | 114 | if (err != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 115 | mp_clear(&dsa->x); |
| wolfSSL | 4:1b0d80432c79 | 116 | XFREE(buf, NULL, DYNAMIC_TYPE_TMP_BUFFER); |
| wolfSSL | 4:1b0d80432c79 | 117 | return err; |
| wolfSSL | 4:1b0d80432c79 | 118 | } |
| wolfSSL | 4:1b0d80432c79 | 119 | |
| wolfSSL | 4:1b0d80432c79 | 120 | err = mp_read_unsigned_bin(&dsa->x, buf, qsize); |
| wolfSSL | 4:1b0d80432c79 | 121 | if (err != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 122 | mp_clear(&dsa->x); |
| wolfSSL | 4:1b0d80432c79 | 123 | XFREE(buf, NULL, DYNAMIC_TYPE_TMP_BUFFER); |
| wolfSSL | 4:1b0d80432c79 | 124 | return err; |
| wolfSSL | 4:1b0d80432c79 | 125 | } |
| wolfSSL | 4:1b0d80432c79 | 126 | } while (mp_cmp_d(&dsa->x, 1) != MP_GT); |
| wolfSSL | 4:1b0d80432c79 | 127 | |
| wolfSSL | 4:1b0d80432c79 | 128 | XFREE(buf, NULL, DYNAMIC_TYPE_TMP_BUFFER); |
| wolfSSL | 4:1b0d80432c79 | 129 | |
| wolfSSL | 4:1b0d80432c79 | 130 | if (mp_init(&dsa->y) != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 131 | mp_clear(&dsa->x); |
| wolfSSL | 4:1b0d80432c79 | 132 | return MP_INIT_E; |
| wolfSSL | 4:1b0d80432c79 | 133 | } |
| wolfSSL | 4:1b0d80432c79 | 134 | |
| wolfSSL | 4:1b0d80432c79 | 135 | /* public key : y = g^x mod p */ |
| wolfSSL | 4:1b0d80432c79 | 136 | err = mp_exptmod(&dsa->g, &dsa->x, &dsa->p, &dsa->y); |
| wolfSSL | 4:1b0d80432c79 | 137 | if (err != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 138 | mp_clear(&dsa->x); |
| wolfSSL | 4:1b0d80432c79 | 139 | mp_clear(&dsa->y); |
| wolfSSL | 4:1b0d80432c79 | 140 | return err; |
| wolfSSL | 4:1b0d80432c79 | 141 | } |
| wolfSSL | 4:1b0d80432c79 | 142 | |
| wolfSSL | 4:1b0d80432c79 | 143 | dsa->type = DSA_PRIVATE; |
| wolfSSL | 4:1b0d80432c79 | 144 | |
| wolfSSL | 4:1b0d80432c79 | 145 | return MP_OKAY; |
| wolfSSL | 4:1b0d80432c79 | 146 | } |
| wolfSSL | 4:1b0d80432c79 | 147 | |
| wolfSSL | 4:1b0d80432c79 | 148 | /* modulus_size in bits */ |
| wolfSSL | 4:1b0d80432c79 | 149 | int wc_MakeDsaParameters(WC_RNG *rng, int modulus_size, DsaKey *dsa) |
| wolfSSL | 4:1b0d80432c79 | 150 | { |
| wolfSSL | 4:1b0d80432c79 | 151 | mp_int tmp, tmp2; |
| wolfSSL | 4:1b0d80432c79 | 152 | int err, msize, qsize, |
| wolfSSL | 4:1b0d80432c79 | 153 | loop_check_prime = 0, |
| wolfSSL | 4:1b0d80432c79 | 154 | check_prime = MP_NO; |
| wolfSSL | 4:1b0d80432c79 | 155 | unsigned char *buf; |
| wolfSSL | 4:1b0d80432c79 | 156 | |
| wolfSSL | 4:1b0d80432c79 | 157 | if (rng == NULL || dsa == NULL) |
| wolfSSL | 4:1b0d80432c79 | 158 | return BAD_FUNC_ARG; |
| wolfSSL | 4:1b0d80432c79 | 159 | |
| wolfSSL | 4:1b0d80432c79 | 160 | /* set group size in bytes from modulus size |
| wolfSSL | 4:1b0d80432c79 | 161 | * FIPS 186-4 defines valid values (1024, 160) (2048, 256) (3072, 256) |
| wolfSSL | 4:1b0d80432c79 | 162 | */ |
| wolfSSL | 4:1b0d80432c79 | 163 | switch (modulus_size) { |
| wolfSSL | 4:1b0d80432c79 | 164 | case 1024: |
| wolfSSL | 4:1b0d80432c79 | 165 | qsize = 20; |
| wolfSSL | 4:1b0d80432c79 | 166 | break; |
| wolfSSL | 4:1b0d80432c79 | 167 | case 2048: |
| wolfSSL | 4:1b0d80432c79 | 168 | case 3072: |
| wolfSSL | 4:1b0d80432c79 | 169 | qsize = 32; |
| wolfSSL | 4:1b0d80432c79 | 170 | break; |
| wolfSSL | 4:1b0d80432c79 | 171 | default: |
| wolfSSL | 4:1b0d80432c79 | 172 | return BAD_FUNC_ARG; |
| wolfSSL | 4:1b0d80432c79 | 173 | break; |
| wolfSSL | 4:1b0d80432c79 | 174 | } |
| wolfSSL | 4:1b0d80432c79 | 175 | |
| wolfSSL | 4:1b0d80432c79 | 176 | /* modulus size in bytes */ |
| wolfSSL | 4:1b0d80432c79 | 177 | msize = modulus_size / 8; |
| wolfSSL | 4:1b0d80432c79 | 178 | |
| wolfSSL | 4:1b0d80432c79 | 179 | /* allocate ram */ |
| wolfSSL | 4:1b0d80432c79 | 180 | buf = (unsigned char *)XMALLOC(msize - qsize, |
| wolfSSL | 4:1b0d80432c79 | 181 | NULL, DYNAMIC_TYPE_TMP_BUFFER); |
| wolfSSL | 4:1b0d80432c79 | 182 | if (buf == NULL) { |
| wolfSSL | 4:1b0d80432c79 | 183 | return MEMORY_E; |
| wolfSSL | 4:1b0d80432c79 | 184 | } |
| wolfSSL | 4:1b0d80432c79 | 185 | |
| wolfSSL | 4:1b0d80432c79 | 186 | /* make a random string that will be multplied against q */ |
| wolfSSL | 4:1b0d80432c79 | 187 | err = wc_RNG_GenerateBlock(rng, buf, msize - qsize); |
| wolfSSL | 4:1b0d80432c79 | 188 | if (err != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 189 | XFREE(buf, NULL, DYNAMIC_TYPE_TMP_BUFFER); |
| wolfSSL | 4:1b0d80432c79 | 190 | return err; |
| wolfSSL | 4:1b0d80432c79 | 191 | } |
| wolfSSL | 4:1b0d80432c79 | 192 | |
| wolfSSL | 4:1b0d80432c79 | 193 | /* force magnitude */ |
| wolfSSL | 4:1b0d80432c79 | 194 | buf[0] |= 0xC0; |
| wolfSSL | 4:1b0d80432c79 | 195 | |
| wolfSSL | 4:1b0d80432c79 | 196 | /* force even */ |
| wolfSSL | 4:1b0d80432c79 | 197 | buf[msize - qsize - 1] &= ~1; |
| wolfSSL | 4:1b0d80432c79 | 198 | |
| wolfSSL | 4:1b0d80432c79 | 199 | if (mp_init_multi(&tmp2, &dsa->p, &dsa->q, 0, 0, 0) != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 200 | mp_clear(&dsa->q); |
| wolfSSL | 4:1b0d80432c79 | 201 | XFREE(buf, NULL, DYNAMIC_TYPE_TMP_BUFFER); |
| wolfSSL | 4:1b0d80432c79 | 202 | return MP_INIT_E; |
| wolfSSL | 4:1b0d80432c79 | 203 | } |
| wolfSSL | 4:1b0d80432c79 | 204 | |
| wolfSSL | 4:1b0d80432c79 | 205 | err = mp_read_unsigned_bin(&tmp2, buf, msize - qsize); |
| wolfSSL | 4:1b0d80432c79 | 206 | if (err != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 207 | mp_clear(&dsa->q); |
| wolfSSL | 4:1b0d80432c79 | 208 | mp_clear(&dsa->p); |
| wolfSSL | 4:1b0d80432c79 | 209 | mp_clear(&tmp2); |
| wolfSSL | 4:1b0d80432c79 | 210 | XFREE(buf, NULL, DYNAMIC_TYPE_TMP_BUFFER); |
| wolfSSL | 4:1b0d80432c79 | 211 | return err; |
| wolfSSL | 4:1b0d80432c79 | 212 | } |
| wolfSSL | 4:1b0d80432c79 | 213 | XFREE(buf, NULL, DYNAMIC_TYPE_TMP_BUFFER); |
| wolfSSL | 4:1b0d80432c79 | 214 | |
| wolfSSL | 4:1b0d80432c79 | 215 | /* make our prime q */ |
| wolfSSL | 4:1b0d80432c79 | 216 | err = mp_rand_prime(&dsa->q, qsize, rng, NULL); |
| wolfSSL | 4:1b0d80432c79 | 217 | if (err != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 218 | mp_clear(&dsa->q); |
| wolfSSL | 4:1b0d80432c79 | 219 | mp_clear(&dsa->p); |
| wolfSSL | 4:1b0d80432c79 | 220 | mp_clear(&tmp2); |
| wolfSSL | 4:1b0d80432c79 | 221 | return err; |
| wolfSSL | 4:1b0d80432c79 | 222 | } |
| wolfSSL | 4:1b0d80432c79 | 223 | |
| wolfSSL | 4:1b0d80432c79 | 224 | /* p = random * q */ |
| wolfSSL | 4:1b0d80432c79 | 225 | err = mp_mul(&dsa->q, &tmp2, &dsa->p); |
| wolfSSL | 4:1b0d80432c79 | 226 | if (err != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 227 | mp_clear(&dsa->q); |
| wolfSSL | 4:1b0d80432c79 | 228 | mp_clear(&dsa->p); |
| wolfSSL | 4:1b0d80432c79 | 229 | mp_clear(&tmp2); |
| wolfSSL | 4:1b0d80432c79 | 230 | return err; |
| wolfSSL | 4:1b0d80432c79 | 231 | } |
| wolfSSL | 4:1b0d80432c79 | 232 | |
| wolfSSL | 4:1b0d80432c79 | 233 | /* p = random * q + 1, so q is a prime divisor of p-1 */ |
| wolfSSL | 4:1b0d80432c79 | 234 | err = mp_add_d(&dsa->p, 1, &dsa->p); |
| wolfSSL | 4:1b0d80432c79 | 235 | if (err != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 236 | mp_clear(&dsa->q); |
| wolfSSL | 4:1b0d80432c79 | 237 | mp_clear(&dsa->p); |
| wolfSSL | 4:1b0d80432c79 | 238 | mp_clear(&tmp2); |
| wolfSSL | 4:1b0d80432c79 | 239 | return err; |
| wolfSSL | 4:1b0d80432c79 | 240 | } |
| wolfSSL | 4:1b0d80432c79 | 241 | |
| wolfSSL | 4:1b0d80432c79 | 242 | if (mp_init(&tmp) != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 243 | mp_clear(&dsa->q); |
| wolfSSL | 4:1b0d80432c79 | 244 | mp_clear(&dsa->p); |
| wolfSSL | 4:1b0d80432c79 | 245 | mp_clear(&tmp2); |
| wolfSSL | 4:1b0d80432c79 | 246 | return MP_INIT_E; |
| wolfSSL | 4:1b0d80432c79 | 247 | } |
| wolfSSL | 4:1b0d80432c79 | 248 | |
| wolfSSL | 4:1b0d80432c79 | 249 | /* tmp = 2q */ |
| wolfSSL | 4:1b0d80432c79 | 250 | err = mp_add(&dsa->q, &dsa->q, &tmp); |
| wolfSSL | 4:1b0d80432c79 | 251 | if (err != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 252 | mp_clear(&dsa->q); |
| wolfSSL | 4:1b0d80432c79 | 253 | mp_clear(&dsa->p); |
| wolfSSL | 4:1b0d80432c79 | 254 | mp_clear(&tmp); |
| wolfSSL | 4:1b0d80432c79 | 255 | mp_clear(&tmp2); |
| wolfSSL | 4:1b0d80432c79 | 256 | return err; |
| wolfSSL | 4:1b0d80432c79 | 257 | } |
| wolfSSL | 4:1b0d80432c79 | 258 | |
| wolfSSL | 4:1b0d80432c79 | 259 | /* loop until p is prime */ |
| wolfSSL | 4:1b0d80432c79 | 260 | while (check_prime == MP_NO) { |
| wolfSSL | 4:1b0d80432c79 | 261 | err = mp_prime_is_prime(&dsa->p, 8, &check_prime); |
| wolfSSL | 4:1b0d80432c79 | 262 | if (err != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 263 | mp_clear(&dsa->q); |
| wolfSSL | 4:1b0d80432c79 | 264 | mp_clear(&dsa->p); |
| wolfSSL | 4:1b0d80432c79 | 265 | mp_clear(&tmp); |
| wolfSSL | 4:1b0d80432c79 | 266 | mp_clear(&tmp2); |
| wolfSSL | 4:1b0d80432c79 | 267 | return err; |
| wolfSSL | 4:1b0d80432c79 | 268 | } |
| wolfSSL | 4:1b0d80432c79 | 269 | |
| wolfSSL | 4:1b0d80432c79 | 270 | if (check_prime != MP_YES) { |
| wolfSSL | 4:1b0d80432c79 | 271 | /* p += 2q */ |
| wolfSSL | 4:1b0d80432c79 | 272 | err = mp_add(&tmp, &dsa->p, &dsa->p); |
| wolfSSL | 4:1b0d80432c79 | 273 | if (err != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 274 | mp_clear(&dsa->q); |
| wolfSSL | 4:1b0d80432c79 | 275 | mp_clear(&dsa->p); |
| wolfSSL | 4:1b0d80432c79 | 276 | mp_clear(&tmp); |
| wolfSSL | 4:1b0d80432c79 | 277 | mp_clear(&tmp2); |
| wolfSSL | 4:1b0d80432c79 | 278 | return err; |
| wolfSSL | 4:1b0d80432c79 | 279 | } |
| wolfSSL | 4:1b0d80432c79 | 280 | |
| wolfSSL | 4:1b0d80432c79 | 281 | loop_check_prime++; |
| wolfSSL | 4:1b0d80432c79 | 282 | } |
| wolfSSL | 4:1b0d80432c79 | 283 | } |
| wolfSSL | 4:1b0d80432c79 | 284 | |
| wolfSSL | 4:1b0d80432c79 | 285 | /* tmp2 += (2*loop_check_prime) |
| wolfSSL | 4:1b0d80432c79 | 286 | * to have p = (q * tmp2) + 1 prime |
| wolfSSL | 4:1b0d80432c79 | 287 | */ |
| wolfSSL | 4:1b0d80432c79 | 288 | if (loop_check_prime) { |
| wolfSSL | 4:1b0d80432c79 | 289 | err = mp_add_d(&tmp2, 2*loop_check_prime, &tmp2); |
| wolfSSL | 4:1b0d80432c79 | 290 | if (err != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 291 | mp_clear(&dsa->q); |
| wolfSSL | 4:1b0d80432c79 | 292 | mp_clear(&dsa->p); |
| wolfSSL | 4:1b0d80432c79 | 293 | mp_clear(&tmp); |
| wolfSSL | 4:1b0d80432c79 | 294 | mp_clear(&tmp2); |
| wolfSSL | 4:1b0d80432c79 | 295 | return err; |
| wolfSSL | 4:1b0d80432c79 | 296 | } |
| wolfSSL | 4:1b0d80432c79 | 297 | } |
| wolfSSL | 4:1b0d80432c79 | 298 | |
| wolfSSL | 4:1b0d80432c79 | 299 | if (mp_init(&dsa->g) != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 300 | mp_clear(&dsa->q); |
| wolfSSL | 4:1b0d80432c79 | 301 | mp_clear(&dsa->p); |
| wolfSSL | 4:1b0d80432c79 | 302 | mp_clear(&tmp); |
| wolfSSL | 4:1b0d80432c79 | 303 | mp_clear(&tmp2); |
| wolfSSL | 4:1b0d80432c79 | 304 | return MP_INIT_E; |
| wolfSSL | 4:1b0d80432c79 | 305 | } |
| wolfSSL | 4:1b0d80432c79 | 306 | |
| wolfSSL | 4:1b0d80432c79 | 307 | /* find a value g for which g^tmp2 != 1 */ |
| wolfSSL | 4:1b0d80432c79 | 308 | mp_set(&dsa->g, 1); |
| wolfSSL | 4:1b0d80432c79 | 309 | |
| wolfSSL | 4:1b0d80432c79 | 310 | do { |
| wolfSSL | 4:1b0d80432c79 | 311 | err = mp_add_d(&dsa->g, 1, &dsa->g); |
| wolfSSL | 4:1b0d80432c79 | 312 | if (err != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 313 | mp_clear(&dsa->q); |
| wolfSSL | 4:1b0d80432c79 | 314 | mp_clear(&dsa->p); |
| wolfSSL | 4:1b0d80432c79 | 315 | mp_clear(&dsa->g); |
| wolfSSL | 4:1b0d80432c79 | 316 | mp_clear(&tmp); |
| wolfSSL | 4:1b0d80432c79 | 317 | mp_clear(&tmp2); |
| wolfSSL | 4:1b0d80432c79 | 318 | return err; |
| wolfSSL | 4:1b0d80432c79 | 319 | } |
| wolfSSL | 4:1b0d80432c79 | 320 | |
| wolfSSL | 4:1b0d80432c79 | 321 | err = mp_exptmod(&dsa->g, &tmp2, &dsa->p, &tmp); |
| wolfSSL | 4:1b0d80432c79 | 322 | if (err != MP_OKAY) { |
| wolfSSL | 4:1b0d80432c79 | 323 | mp_clear(&dsa->q); |
| wolfSSL | 4:1b0d80432c79 | 324 | mp_clear(&dsa->p); |
| wolfSSL | 4:1b0d80432c79 | 325 | mp_clear(&dsa->g); |
| wolfSSL | 4:1b0d80432c79 | 326 | mp_clear(&tmp); |
| wolfSSL | 4:1b0d80432c79 | 327 | mp_clear(&tmp2); |
| wolfSSL | 4:1b0d80432c79 | 328 | return err; |
| wolfSSL | 4:1b0d80432c79 | 329 | } |
| wolfSSL | 4:1b0d80432c79 | 330 | |
| wolfSSL | 4:1b0d80432c79 | 331 | } while (mp_cmp_d(&tmp, 1) == MP_EQ); |
| wolfSSL | 4:1b0d80432c79 | 332 | |
| wolfSSL | 4:1b0d80432c79 | 333 | /* at this point tmp generates a group of order q mod p */ |
| wolfSSL | 4:1b0d80432c79 | 334 | mp_exch(&tmp, &dsa->g); |
| wolfSSL | 4:1b0d80432c79 | 335 | |
| wolfSSL | 4:1b0d80432c79 | 336 | mp_clear(&tmp); |
| wolfSSL | 4:1b0d80432c79 | 337 | mp_clear(&tmp2); |
| wolfSSL | 4:1b0d80432c79 | 338 | |
| wolfSSL | 4:1b0d80432c79 | 339 | return MP_OKAY; |
| wolfSSL | 4:1b0d80432c79 | 340 | } |
| wolfSSL | 4:1b0d80432c79 | 341 | #endif /* WOLFSSL_KEY_GEN */ |
| wolfSSL | 4:1b0d80432c79 | 342 | |
| wolfSSL | 4:1b0d80432c79 | 343 | |
| wolfSSL | 4:1b0d80432c79 | 344 | int wc_DsaSign(const byte* digest, byte* out, DsaKey* key, WC_RNG* rng) |
| wolfSSL | 4:1b0d80432c79 | 345 | { |
| wolfSSL | 4:1b0d80432c79 | 346 | mp_int k, kInv, r, s, H; |
| wolfSSL | 4:1b0d80432c79 | 347 | int ret, sz; |
| wolfSSL | 4:1b0d80432c79 | 348 | byte buffer[DSA_HALF_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 349 | |
| wolfSSL | 4:1b0d80432c79 | 350 | sz = min(sizeof(buffer), mp_unsigned_bin_size(&key->q)); |
| wolfSSL | 4:1b0d80432c79 | 351 | |
| wolfSSL | 4:1b0d80432c79 | 352 | /* generate k */ |
| wolfSSL | 4:1b0d80432c79 | 353 | ret = wc_RNG_GenerateBlock(rng, buffer, sz); |
| wolfSSL | 4:1b0d80432c79 | 354 | if (ret != 0) |
| wolfSSL | 4:1b0d80432c79 | 355 | return ret; |
| wolfSSL | 4:1b0d80432c79 | 356 | |
| wolfSSL | 4:1b0d80432c79 | 357 | buffer[0] |= 0x0C; |
| wolfSSL | 4:1b0d80432c79 | 358 | |
| wolfSSL | 4:1b0d80432c79 | 359 | if (mp_init_multi(&k, &kInv, &r, &s, &H, 0) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 360 | return MP_INIT_E; |
| wolfSSL | 4:1b0d80432c79 | 361 | |
| wolfSSL | 4:1b0d80432c79 | 362 | if (mp_read_unsigned_bin(&k, buffer, sz) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 363 | ret = MP_READ_E; |
| wolfSSL | 4:1b0d80432c79 | 364 | |
| wolfSSL | 4:1b0d80432c79 | 365 | if (ret == 0 && mp_cmp_d(&k, 1) != MP_GT) |
| wolfSSL | 4:1b0d80432c79 | 366 | ret = MP_CMP_E; |
| wolfSSL | 4:1b0d80432c79 | 367 | |
| wolfSSL | 4:1b0d80432c79 | 368 | /* inverse k mod q */ |
| wolfSSL | 4:1b0d80432c79 | 369 | if (ret == 0 && mp_invmod(&k, &key->q, &kInv) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 370 | ret = MP_INVMOD_E; |
| wolfSSL | 4:1b0d80432c79 | 371 | |
| wolfSSL | 4:1b0d80432c79 | 372 | /* generate r, r = (g exp k mod p) mod q */ |
| wolfSSL | 4:1b0d80432c79 | 373 | if (ret == 0 && mp_exptmod(&key->g, &k, &key->p, &r) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 374 | ret = MP_EXPTMOD_E; |
| wolfSSL | 4:1b0d80432c79 | 375 | |
| wolfSSL | 4:1b0d80432c79 | 376 | if (ret == 0 && mp_mod(&r, &key->q, &r) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 377 | ret = MP_MOD_E; |
| wolfSSL | 4:1b0d80432c79 | 378 | |
| wolfSSL | 4:1b0d80432c79 | 379 | /* generate H from sha digest */ |
| wolfSSL | 4:1b0d80432c79 | 380 | if (ret == 0 && mp_read_unsigned_bin(&H, digest,SHA_DIGEST_SIZE) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 381 | ret = MP_READ_E; |
| wolfSSL | 4:1b0d80432c79 | 382 | |
| wolfSSL | 4:1b0d80432c79 | 383 | /* generate s, s = (kInv * (H + x*r)) % q */ |
| wolfSSL | 4:1b0d80432c79 | 384 | if (ret == 0 && mp_mul(&key->x, &r, &s) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 385 | ret = MP_MUL_E; |
| wolfSSL | 4:1b0d80432c79 | 386 | |
| wolfSSL | 4:1b0d80432c79 | 387 | if (ret == 0 && mp_add(&s, &H, &s) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 388 | ret = MP_ADD_E; |
| wolfSSL | 4:1b0d80432c79 | 389 | |
| wolfSSL | 4:1b0d80432c79 | 390 | if (ret == 0 && mp_mulmod(&s, &kInv, &key->q, &s) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 391 | ret = MP_MULMOD_E; |
| wolfSSL | 4:1b0d80432c79 | 392 | |
| wolfSSL | 4:1b0d80432c79 | 393 | /* write out */ |
| wolfSSL | 4:1b0d80432c79 | 394 | if (ret == 0) { |
| wolfSSL | 4:1b0d80432c79 | 395 | int rSz = mp_unsigned_bin_size(&r); |
| wolfSSL | 4:1b0d80432c79 | 396 | int sSz = mp_unsigned_bin_size(&s); |
| wolfSSL | 4:1b0d80432c79 | 397 | |
| wolfSSL | 4:1b0d80432c79 | 398 | if (rSz == DSA_HALF_SIZE - 1) { |
| wolfSSL | 4:1b0d80432c79 | 399 | out[0] = 0; |
| wolfSSL | 4:1b0d80432c79 | 400 | out++; |
| wolfSSL | 4:1b0d80432c79 | 401 | } |
| wolfSSL | 4:1b0d80432c79 | 402 | |
| wolfSSL | 4:1b0d80432c79 | 403 | if (mp_to_unsigned_bin(&r, out) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 404 | ret = MP_TO_E; |
| wolfSSL | 4:1b0d80432c79 | 405 | else { |
| wolfSSL | 4:1b0d80432c79 | 406 | if (sSz == DSA_HALF_SIZE - 1) { |
| wolfSSL | 4:1b0d80432c79 | 407 | out[rSz] = 0; |
| wolfSSL | 4:1b0d80432c79 | 408 | out++; |
| wolfSSL | 4:1b0d80432c79 | 409 | } |
| wolfSSL | 4:1b0d80432c79 | 410 | ret = mp_to_unsigned_bin(&s, out + rSz); |
| wolfSSL | 4:1b0d80432c79 | 411 | } |
| wolfSSL | 4:1b0d80432c79 | 412 | } |
| wolfSSL | 4:1b0d80432c79 | 413 | |
| wolfSSL | 4:1b0d80432c79 | 414 | mp_clear(&H); |
| wolfSSL | 4:1b0d80432c79 | 415 | mp_clear(&s); |
| wolfSSL | 4:1b0d80432c79 | 416 | mp_clear(&r); |
| wolfSSL | 4:1b0d80432c79 | 417 | mp_clear(&kInv); |
| wolfSSL | 4:1b0d80432c79 | 418 | mp_clear(&k); |
| wolfSSL | 4:1b0d80432c79 | 419 | |
| wolfSSL | 4:1b0d80432c79 | 420 | return ret; |
| wolfSSL | 4:1b0d80432c79 | 421 | } |
| wolfSSL | 4:1b0d80432c79 | 422 | |
| wolfSSL | 4:1b0d80432c79 | 423 | |
| wolfSSL | 4:1b0d80432c79 | 424 | int wc_DsaVerify(const byte* digest, const byte* sig, DsaKey* key, int* answer) |
| wolfSSL | 4:1b0d80432c79 | 425 | { |
| wolfSSL | 4:1b0d80432c79 | 426 | mp_int w, u1, u2, v, r, s; |
| wolfSSL | 4:1b0d80432c79 | 427 | int ret = 0; |
| wolfSSL | 4:1b0d80432c79 | 428 | |
| wolfSSL | 4:1b0d80432c79 | 429 | if (mp_init_multi(&w, &u1, &u2, &v, &r, &s) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 430 | return MP_INIT_E; |
| wolfSSL | 4:1b0d80432c79 | 431 | |
| wolfSSL | 4:1b0d80432c79 | 432 | /* set r and s from signature */ |
| wolfSSL | 4:1b0d80432c79 | 433 | if (mp_read_unsigned_bin(&r, sig, DSA_HALF_SIZE) != MP_OKAY || |
| wolfSSL | 4:1b0d80432c79 | 434 | mp_read_unsigned_bin(&s, sig + DSA_HALF_SIZE, DSA_HALF_SIZE) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 435 | ret = MP_READ_E; |
| wolfSSL | 4:1b0d80432c79 | 436 | |
| wolfSSL | 4:1b0d80432c79 | 437 | /* sanity checks */ |
| wolfSSL | 4:1b0d80432c79 | 438 | if (ret == 0) { |
| wolfSSL | 4:1b0d80432c79 | 439 | if (mp_iszero(&r) == MP_YES || mp_iszero(&s) == MP_YES || |
| wolfSSL | 4:1b0d80432c79 | 440 | mp_cmp(&r, &key->q) != MP_LT || mp_cmp(&s, &key->q) != MP_LT) { |
| wolfSSL | 4:1b0d80432c79 | 441 | ret = MP_ZERO_E; |
| wolfSSL | 4:1b0d80432c79 | 442 | } |
| wolfSSL | 4:1b0d80432c79 | 443 | } |
| wolfSSL | 4:1b0d80432c79 | 444 | |
| wolfSSL | 4:1b0d80432c79 | 445 | /* put H into u1 from sha digest */ |
| wolfSSL | 4:1b0d80432c79 | 446 | if (ret == 0 && mp_read_unsigned_bin(&u1,digest,SHA_DIGEST_SIZE) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 447 | ret = MP_READ_E; |
| wolfSSL | 4:1b0d80432c79 | 448 | |
| wolfSSL | 4:1b0d80432c79 | 449 | /* w = s invmod q */ |
| wolfSSL | 4:1b0d80432c79 | 450 | if (ret == 0 && mp_invmod(&s, &key->q, &w) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 451 | ret = MP_INVMOD_E; |
| wolfSSL | 4:1b0d80432c79 | 452 | |
| wolfSSL | 4:1b0d80432c79 | 453 | /* u1 = (H * w) % q */ |
| wolfSSL | 4:1b0d80432c79 | 454 | if (ret == 0 && mp_mulmod(&u1, &w, &key->q, &u1) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 455 | ret = MP_MULMOD_E; |
| wolfSSL | 4:1b0d80432c79 | 456 | |
| wolfSSL | 4:1b0d80432c79 | 457 | /* u2 = (r * w) % q */ |
| wolfSSL | 4:1b0d80432c79 | 458 | if (ret == 0 && mp_mulmod(&r, &w, &key->q, &u2) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 459 | ret = MP_MULMOD_E; |
| wolfSSL | 4:1b0d80432c79 | 460 | |
| wolfSSL | 4:1b0d80432c79 | 461 | /* verify v = ((g^u1 * y^u2) mod p) mod q */ |
| wolfSSL | 4:1b0d80432c79 | 462 | if (ret == 0 && mp_exptmod(&key->g, &u1, &key->p, &u1) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 463 | ret = MP_EXPTMOD_E; |
| wolfSSL | 4:1b0d80432c79 | 464 | |
| wolfSSL | 4:1b0d80432c79 | 465 | if (ret == 0 && mp_exptmod(&key->y, &u2, &key->p, &u2) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 466 | ret = MP_EXPTMOD_E; |
| wolfSSL | 4:1b0d80432c79 | 467 | |
| wolfSSL | 4:1b0d80432c79 | 468 | if (ret == 0 && mp_mulmod(&u1, &u2, &key->p, &v) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 469 | ret = MP_MULMOD_E; |
| wolfSSL | 4:1b0d80432c79 | 470 | |
| wolfSSL | 4:1b0d80432c79 | 471 | if (ret == 0 && mp_mod(&v, &key->q, &v) != MP_OKAY) |
| wolfSSL | 4:1b0d80432c79 | 472 | ret = MP_MULMOD_E; |
| wolfSSL | 4:1b0d80432c79 | 473 | |
| wolfSSL | 4:1b0d80432c79 | 474 | /* do they match */ |
| wolfSSL | 4:1b0d80432c79 | 475 | if (ret == 0 && mp_cmp(&r, &v) == MP_EQ) |
| wolfSSL | 4:1b0d80432c79 | 476 | *answer = 1; |
| wolfSSL | 4:1b0d80432c79 | 477 | else |
| wolfSSL | 4:1b0d80432c79 | 478 | *answer = 0; |
| wolfSSL | 4:1b0d80432c79 | 479 | |
| wolfSSL | 4:1b0d80432c79 | 480 | mp_clear(&s); |
| wolfSSL | 4:1b0d80432c79 | 481 | mp_clear(&r); |
| wolfSSL | 4:1b0d80432c79 | 482 | mp_clear(&u1); |
| wolfSSL | 4:1b0d80432c79 | 483 | mp_clear(&u2); |
| wolfSSL | 4:1b0d80432c79 | 484 | mp_clear(&w); |
| wolfSSL | 4:1b0d80432c79 | 485 | mp_clear(&v); |
| wolfSSL | 4:1b0d80432c79 | 486 | |
| wolfSSL | 4:1b0d80432c79 | 487 | return ret; |
| wolfSSL | 4:1b0d80432c79 | 488 | } |
| wolfSSL | 4:1b0d80432c79 | 489 | |
| wolfSSL | 4:1b0d80432c79 | 490 | |
| wolfSSL | 4:1b0d80432c79 | 491 | #endif /* NO_DSA */ |
| wolfSSL | 4:1b0d80432c79 | 492 | |
| wolfSSL | 4:1b0d80432c79 | 493 |