diff options
Diffstat (limited to 'src/lib/libcrypto/dsa/dsa_ossl.c')
-rw-r--r-- | src/lib/libcrypto/dsa/dsa_ossl.c | 321 |
1 files changed, 321 insertions, 0 deletions
diff --git a/src/lib/libcrypto/dsa/dsa_ossl.c b/src/lib/libcrypto/dsa/dsa_ossl.c new file mode 100644 index 0000000000..b51cf6ad8d --- /dev/null +++ b/src/lib/libcrypto/dsa/dsa_ossl.c | |||
@@ -0,0 +1,321 @@ | |||
1 | /* crypto/dsa/dsa_ossl.c */ | ||
2 | /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) | ||
3 | * All rights reserved. | ||
4 | * | ||
5 | * This package is an SSL implementation written | ||
6 | * by Eric Young (eay@cryptsoft.com). | ||
7 | * The implementation was written so as to conform with Netscapes SSL. | ||
8 | * | ||
9 | * This library is free for commercial and non-commercial use as long as | ||
10 | * the following conditions are aheared to. The following conditions | ||
11 | * apply to all code found in this distribution, be it the RC4, RSA, | ||
12 | * lhash, DES, etc., code; not just the SSL code. The SSL documentation | ||
13 | * included with this distribution is covered by the same copyright terms | ||
14 | * except that the holder is Tim Hudson (tjh@cryptsoft.com). | ||
15 | * | ||
16 | * Copyright remains Eric Young's, and as such any Copyright notices in | ||
17 | * the code are not to be removed. | ||
18 | * If this package is used in a product, Eric Young should be given attribution | ||
19 | * as the author of the parts of the library used. | ||
20 | * This can be in the form of a textual message at program startup or | ||
21 | * in documentation (online or textual) provided with the package. | ||
22 | * | ||
23 | * Redistribution and use in source and binary forms, with or without | ||
24 | * modification, are permitted provided that the following conditions | ||
25 | * are met: | ||
26 | * 1. Redistributions of source code must retain the copyright | ||
27 | * notice, this list of conditions and the following disclaimer. | ||
28 | * 2. Redistributions in binary form must reproduce the above copyright | ||
29 | * notice, this list of conditions and the following disclaimer in the | ||
30 | * documentation and/or other materials provided with the distribution. | ||
31 | * 3. All advertising materials mentioning features or use of this software | ||
32 | * must display the following acknowledgement: | ||
33 | * "This product includes cryptographic software written by | ||
34 | * Eric Young (eay@cryptsoft.com)" | ||
35 | * The word 'cryptographic' can be left out if the rouines from the library | ||
36 | * being used are not cryptographic related :-). | ||
37 | * 4. If you include any Windows specific code (or a derivative thereof) from | ||
38 | * the apps directory (application code) you must include an acknowledgement: | ||
39 | * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" | ||
40 | * | ||
41 | * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND | ||
42 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | ||
43 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | ||
44 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE | ||
45 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | ||
46 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | ||
47 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | ||
48 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | ||
49 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | ||
50 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | ||
51 | * SUCH DAMAGE. | ||
52 | * | ||
53 | * The licence and distribution terms for any publically available version or | ||
54 | * derivative of this code cannot be changed. i.e. this code cannot simply be | ||
55 | * copied and put under another distribution licence | ||
56 | * [including the GNU Public Licence.] | ||
57 | */ | ||
58 | |||
59 | /* Original version from Steven Schoch <schoch@sheba.arc.nasa.gov> */ | ||
60 | |||
61 | #include <stdio.h> | ||
62 | #include "cryptlib.h" | ||
63 | #include <openssl/bn.h> | ||
64 | #include <openssl/dsa.h> | ||
65 | #include <openssl/rand.h> | ||
66 | #include <openssl/asn1.h> | ||
67 | |||
68 | static DSA_SIG *dsa_do_sign(const unsigned char *dgst, int dlen, DSA *dsa); | ||
69 | static int dsa_sign_setup(DSA *dsa, BN_CTX *ctx_in, BIGNUM **kinvp, BIGNUM **rp); | ||
70 | static int dsa_do_verify(const unsigned char *dgst, int dgst_len, DSA_SIG *sig, | ||
71 | DSA *dsa); | ||
72 | static int dsa_init(DSA *dsa); | ||
73 | static int dsa_finish(DSA *dsa); | ||
74 | static int dsa_mod_exp(DSA *dsa, BIGNUM *rr, BIGNUM *a1, BIGNUM *p1, | ||
75 | BIGNUM *a2, BIGNUM *p2, BIGNUM *m, BN_CTX *ctx, | ||
76 | BN_MONT_CTX *in_mont); | ||
77 | static int dsa_bn_mod_exp(DSA *dsa, BIGNUM *r, BIGNUM *a, const BIGNUM *p, | ||
78 | const BIGNUM *m, BN_CTX *ctx, | ||
79 | BN_MONT_CTX *m_ctx); | ||
80 | |||
81 | static DSA_METHOD openssl_dsa_meth = { | ||
82 | "OpenSSL DSA method", | ||
83 | dsa_do_sign, | ||
84 | dsa_sign_setup, | ||
85 | dsa_do_verify, | ||
86 | dsa_mod_exp, | ||
87 | dsa_bn_mod_exp, | ||
88 | dsa_init, | ||
89 | dsa_finish, | ||
90 | 0, | ||
91 | NULL | ||
92 | }; | ||
93 | |||
94 | DSA_METHOD *DSA_OpenSSL(void) | ||
95 | { | ||
96 | return &openssl_dsa_meth; | ||
97 | } | ||
98 | |||
99 | static DSA_SIG *dsa_do_sign(const unsigned char *dgst, int dlen, DSA *dsa) | ||
100 | { | ||
101 | BIGNUM *kinv=NULL,*r=NULL,*s=NULL; | ||
102 | BIGNUM m; | ||
103 | BIGNUM xr; | ||
104 | BN_CTX *ctx=NULL; | ||
105 | int i,reason=ERR_R_BN_LIB; | ||
106 | DSA_SIG *ret=NULL; | ||
107 | |||
108 | BN_init(&m); | ||
109 | BN_init(&xr); | ||
110 | s=BN_new(); | ||
111 | if (s == NULL) goto err; | ||
112 | |||
113 | i=BN_num_bytes(dsa->q); /* should be 20 */ | ||
114 | if ((dlen > i) || (dlen > 50)) | ||
115 | { | ||
116 | reason=DSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE; | ||
117 | goto err; | ||
118 | } | ||
119 | |||
120 | ctx=BN_CTX_new(); | ||
121 | if (ctx == NULL) goto err; | ||
122 | |||
123 | if ((dsa->kinv == NULL) || (dsa->r == NULL)) | ||
124 | { | ||
125 | if (!DSA_sign_setup(dsa,ctx,&kinv,&r)) goto err; | ||
126 | } | ||
127 | else | ||
128 | { | ||
129 | kinv=dsa->kinv; | ||
130 | dsa->kinv=NULL; | ||
131 | r=dsa->r; | ||
132 | dsa->r=NULL; | ||
133 | } | ||
134 | |||
135 | if (BN_bin2bn(dgst,dlen,&m) == NULL) goto err; | ||
136 | |||
137 | /* Compute s = inv(k) (m + xr) mod q */ | ||
138 | if (!BN_mod_mul(&xr,dsa->priv_key,r,dsa->q,ctx)) goto err;/* s = xr */ | ||
139 | if (!BN_add(s, &xr, &m)) goto err; /* s = m + xr */ | ||
140 | if (BN_cmp(s,dsa->q) > 0) | ||
141 | BN_sub(s,s,dsa->q); | ||
142 | if (!BN_mod_mul(s,s,kinv,dsa->q,ctx)) goto err; | ||
143 | |||
144 | ret=DSA_SIG_new(); | ||
145 | if (ret == NULL) goto err; | ||
146 | ret->r = r; | ||
147 | ret->s = s; | ||
148 | |||
149 | err: | ||
150 | if (!ret) | ||
151 | { | ||
152 | DSAerr(DSA_F_DSA_DO_SIGN,reason); | ||
153 | BN_free(r); | ||
154 | BN_free(s); | ||
155 | } | ||
156 | if (ctx != NULL) BN_CTX_free(ctx); | ||
157 | BN_clear_free(&m); | ||
158 | BN_clear_free(&xr); | ||
159 | if (kinv != NULL) /* dsa->kinv is NULL now if we used it */ | ||
160 | BN_clear_free(kinv); | ||
161 | return(ret); | ||
162 | } | ||
163 | |||
164 | static int dsa_sign_setup(DSA *dsa, BN_CTX *ctx_in, BIGNUM **kinvp, BIGNUM **rp) | ||
165 | { | ||
166 | BN_CTX *ctx; | ||
167 | BIGNUM k,*kinv=NULL,*r=NULL; | ||
168 | int ret=0; | ||
169 | |||
170 | if (ctx_in == NULL) | ||
171 | { | ||
172 | if ((ctx=BN_CTX_new()) == NULL) goto err; | ||
173 | } | ||
174 | else | ||
175 | ctx=ctx_in; | ||
176 | |||
177 | BN_init(&k); | ||
178 | if ((r=BN_new()) == NULL) goto err; | ||
179 | kinv=NULL; | ||
180 | |||
181 | /* Get random k */ | ||
182 | for (;;) | ||
183 | { | ||
184 | if (!BN_rand(&k, BN_num_bits(dsa->q), 1, 0)) goto err; | ||
185 | if (BN_cmp(&k,dsa->q) >= 0) | ||
186 | BN_sub(&k,&k,dsa->q); | ||
187 | if (!BN_is_zero(&k)) break; | ||
188 | } | ||
189 | |||
190 | if ((dsa->method_mont_p == NULL) && (dsa->flags & DSA_FLAG_CACHE_MONT_P)) | ||
191 | { | ||
192 | if ((dsa->method_mont_p=(char *)BN_MONT_CTX_new()) != NULL) | ||
193 | if (!BN_MONT_CTX_set((BN_MONT_CTX *)dsa->method_mont_p, | ||
194 | dsa->p,ctx)) goto err; | ||
195 | } | ||
196 | |||
197 | /* Compute r = (g^k mod p) mod q */ | ||
198 | if (!dsa->meth->bn_mod_exp(dsa, r,dsa->g,&k,dsa->p,ctx, | ||
199 | (BN_MONT_CTX *)dsa->method_mont_p)) goto err; | ||
200 | if (!BN_mod(r,r,dsa->q,ctx)) goto err; | ||
201 | |||
202 | /* Compute part of 's = inv(k) (m + xr) mod q' */ | ||
203 | if ((kinv=BN_mod_inverse(NULL,&k,dsa->q,ctx)) == NULL) goto err; | ||
204 | |||
205 | if (*kinvp != NULL) BN_clear_free(*kinvp); | ||
206 | *kinvp=kinv; | ||
207 | kinv=NULL; | ||
208 | if (*rp != NULL) BN_clear_free(*rp); | ||
209 | *rp=r; | ||
210 | ret=1; | ||
211 | err: | ||
212 | if (!ret) | ||
213 | { | ||
214 | DSAerr(DSA_F_DSA_SIGN_SETUP,ERR_R_BN_LIB); | ||
215 | if (kinv != NULL) BN_clear_free(kinv); | ||
216 | if (r != NULL) BN_clear_free(r); | ||
217 | } | ||
218 | if (ctx_in == NULL) BN_CTX_free(ctx); | ||
219 | if (kinv != NULL) BN_clear_free(kinv); | ||
220 | BN_clear_free(&k); | ||
221 | return(ret); | ||
222 | } | ||
223 | |||
224 | static int dsa_do_verify(const unsigned char *dgst, int dgst_len, DSA_SIG *sig, | ||
225 | DSA *dsa) | ||
226 | { | ||
227 | BN_CTX *ctx; | ||
228 | BIGNUM u1,u2,t1; | ||
229 | BN_MONT_CTX *mont=NULL; | ||
230 | int ret = -1; | ||
231 | |||
232 | if ((ctx=BN_CTX_new()) == NULL) goto err; | ||
233 | BN_init(&u1); | ||
234 | BN_init(&u2); | ||
235 | BN_init(&t1); | ||
236 | |||
237 | /* Calculate W = inv(S) mod Q | ||
238 | * save W in u2 */ | ||
239 | if ((BN_mod_inverse(&u2,sig->s,dsa->q,ctx)) == NULL) goto err; | ||
240 | |||
241 | /* save M in u1 */ | ||
242 | if (BN_bin2bn(dgst,dgst_len,&u1) == NULL) goto err; | ||
243 | |||
244 | /* u1 = M * w mod q */ | ||
245 | if (!BN_mod_mul(&u1,&u1,&u2,dsa->q,ctx)) goto err; | ||
246 | |||
247 | /* u2 = r * w mod q */ | ||
248 | if (!BN_mod_mul(&u2,sig->r,&u2,dsa->q,ctx)) goto err; | ||
249 | |||
250 | if ((dsa->method_mont_p == NULL) && (dsa->flags & DSA_FLAG_CACHE_MONT_P)) | ||
251 | { | ||
252 | if ((dsa->method_mont_p=(char *)BN_MONT_CTX_new()) != NULL) | ||
253 | if (!BN_MONT_CTX_set((BN_MONT_CTX *)dsa->method_mont_p, | ||
254 | dsa->p,ctx)) goto err; | ||
255 | } | ||
256 | mont=(BN_MONT_CTX *)dsa->method_mont_p; | ||
257 | |||
258 | #if 0 | ||
259 | { | ||
260 | BIGNUM t2; | ||
261 | |||
262 | BN_init(&t2); | ||
263 | /* v = ( g^u1 * y^u2 mod p ) mod q */ | ||
264 | /* let t1 = g ^ u1 mod p */ | ||
265 | if (!BN_mod_exp_mont(&t1,dsa->g,&u1,dsa->p,ctx,mont)) goto err; | ||
266 | /* let t2 = y ^ u2 mod p */ | ||
267 | if (!BN_mod_exp_mont(&t2,dsa->pub_key,&u2,dsa->p,ctx,mont)) goto err; | ||
268 | /* let u1 = t1 * t2 mod p */ | ||
269 | if (!BN_mod_mul(&u1,&t1,&t2,dsa->p,ctx)) goto err_bn; | ||
270 | BN_free(&t2); | ||
271 | } | ||
272 | /* let u1 = u1 mod q */ | ||
273 | if (!BN_mod(&u1,&u1,dsa->q,ctx)) goto err; | ||
274 | #else | ||
275 | { | ||
276 | if (!dsa->meth->dsa_mod_exp(dsa, &t1,dsa->g,&u1,dsa->pub_key,&u2, | ||
277 | dsa->p,ctx,mont)) goto err; | ||
278 | /* BN_copy(&u1,&t1); */ | ||
279 | /* let u1 = u1 mod q */ | ||
280 | if (!BN_mod(&u1,&t1,dsa->q,ctx)) goto err; | ||
281 | } | ||
282 | #endif | ||
283 | /* V is now in u1. If the signature is correct, it will be | ||
284 | * equal to R. */ | ||
285 | ret=(BN_ucmp(&u1, sig->r) == 0); | ||
286 | |||
287 | err: | ||
288 | if (ret != 1) DSAerr(DSA_F_DSA_DO_VERIFY,ERR_R_BN_LIB); | ||
289 | if (ctx != NULL) BN_CTX_free(ctx); | ||
290 | BN_free(&u1); | ||
291 | BN_free(&u2); | ||
292 | BN_free(&t1); | ||
293 | return(ret); | ||
294 | } | ||
295 | |||
296 | static int dsa_init(DSA *dsa) | ||
297 | { | ||
298 | dsa->flags|=DSA_FLAG_CACHE_MONT_P; | ||
299 | return(1); | ||
300 | } | ||
301 | |||
302 | static int dsa_finish(DSA *dsa) | ||
303 | { | ||
304 | if(dsa->method_mont_p) | ||
305 | BN_MONT_CTX_free((BN_MONT_CTX *)dsa->method_mont_p); | ||
306 | return(1); | ||
307 | } | ||
308 | |||
309 | static int dsa_mod_exp(DSA *dsa, BIGNUM *rr, BIGNUM *a1, BIGNUM *p1, | ||
310 | BIGNUM *a2, BIGNUM *p2, BIGNUM *m, BN_CTX *ctx, | ||
311 | BN_MONT_CTX *in_mont) | ||
312 | { | ||
313 | return BN_mod_exp2_mont(rr, a1, p1, a2, p2, m, ctx, in_mont); | ||
314 | } | ||
315 | |||
316 | static int dsa_bn_mod_exp(DSA *dsa, BIGNUM *r, BIGNUM *a, const BIGNUM *p, | ||
317 | const BIGNUM *m, BN_CTX *ctx, | ||
318 | BN_MONT_CTX *m_ctx) | ||
319 | { | ||
320 | return BN_mod_exp_mont(r, a, p, m, ctx, m_ctx); | ||
321 | } | ||