1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
4 * This package is an SSL implementation written
5 * by Eric Young (eay@cryptsoft.com).
6 * The implementation was written so as to conform with Netscapes SSL.
8 * This library is free for commercial and non-commercial use as long as
9 * the following conditions are aheared to. The following conditions
10 * apply to all code found in this distribution, be it the RC4, RSA,
11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
12 * included with this distribution is covered by the same copyright terms
13 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 * Copyright remains Eric Young's, and as such any Copyright notices in
16 * the code are not to be removed.
17 * If this package is used in a product, Eric Young should be given attribution
18 * as the author of the parts of the library used.
19 * This can be in the form of a textual message at program startup or
20 * in documentation (online or textual) provided with the package.
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
25 * 1. Redistributions of source code must retain the copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
30 * 3. All advertising materials mentioning features or use of this software
31 * must display the following acknowledgement:
32 * "This product includes cryptographic software written by
33 * Eric Young (eay@cryptsoft.com)"
34 * The word 'cryptographic' can be left out if the rouines from the library
35 * being used are not cryptographic related :-).
36 * 4. If you include any Windows specific code (or a derivative thereof) from
37 * the apps directory (application code) you must include an acknowledgement:
38 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52 * The licence and distribution terms for any publically available version or
53 * derivative of this code cannot be changed. i.e. this code cannot simply be
54 * copied and put under another distribution licence
55 * [including the GNU Public Licence.]
59 * Parameter generation follows the updated Appendix 2.2 for FIPS PUB 186,
60 * also Appendix 2.2 of FIPS PUB 186-1 (i.e. use SHA as defined in FIPS PUB
63 #define xxxHASH EVP_sha1()
65 #include <openssl/opensslconf.h>
67 #include "internal/cryptlib.h"
68 #include <openssl/evp.h>
69 #include <openssl/bn.h>
70 #include <openssl/rand.h>
71 #include <openssl/sha.h>
74 int DSA_generate_parameters_ex(DSA
*ret
, int bits
,
75 const unsigned char *seed_in
, int seed_len
,
76 int *counter_ret
, unsigned long *h_ret
,
79 if (ret
->meth
->dsa_paramgen
)
80 return ret
->meth
->dsa_paramgen(ret
, bits
, seed_in
, seed_len
,
81 counter_ret
, h_ret
, cb
);
83 const EVP_MD
*evpmd
= bits
>= 2048 ? EVP_sha256() : EVP_sha1();
84 size_t qbits
= EVP_MD_size(evpmd
) * 8;
86 return dsa_builtin_paramgen(ret
, bits
, qbits
, evpmd
,
87 seed_in
, seed_len
, NULL
, counter_ret
,
92 int dsa_builtin_paramgen(DSA
*ret
, size_t bits
, size_t qbits
,
93 const EVP_MD
*evpmd
, const unsigned char *seed_in
,
94 size_t seed_len
, unsigned char *seed_out
,
95 int *counter_ret
, unsigned long *h_ret
, BN_GENCB
*cb
)
98 unsigned char seed
[SHA256_DIGEST_LENGTH
];
99 unsigned char md
[SHA256_DIGEST_LENGTH
];
100 unsigned char buf
[SHA256_DIGEST_LENGTH
], buf2
[SHA256_DIGEST_LENGTH
];
101 BIGNUM
*r0
, *W
, *X
, *c
, *test
;
102 BIGNUM
*g
= NULL
, *q
= NULL
, *p
= NULL
;
103 BN_MONT_CTX
*mont
= NULL
;
104 int i
, k
, n
= 0, m
= 0, qsize
= qbits
>> 3;
110 if (qsize
!= SHA_DIGEST_LENGTH
&& qsize
!= SHA224_DIGEST_LENGTH
&&
111 qsize
!= SHA256_DIGEST_LENGTH
)
116 /* use SHA1 as default */
122 bits
= (bits
+ 63) / 64 * 64;
124 if (seed_in
!= NULL
) {
125 if (seed_len
< (size_t)qsize
)
127 if (seed_len
> (size_t)qsize
) {
128 /* Only consume as much seed as is expected. */
131 memcpy(seed
, seed_in
, seed_len
);
134 if ((mont
= BN_MONT_CTX_new()) == NULL
)
137 if ((ctx
= BN_CTX_new()) == NULL
)
142 r0
= BN_CTX_get(ctx
);
149 test
= BN_CTX_get(ctx
);
151 if (!BN_lshift(test
, BN_value_one(), bits
- 1))
155 for (;;) { /* find q */
156 int use_random_seed
= (seed_in
== NULL
);
159 if (!BN_GENCB_call(cb
, 0, m
++))
162 if (use_random_seed
) {
163 if (RAND_bytes(seed
, qsize
) <= 0)
166 /* If we come back through, use random seed next time. */
169 memcpy(buf
, seed
, qsize
);
170 memcpy(buf2
, seed
, qsize
);
171 /* precompute "SEED + 1" for step 7: */
172 for (i
= qsize
- 1; i
>= 0; i
--) {
179 if (!EVP_Digest(seed
, qsize
, md
, NULL
, evpmd
, NULL
))
181 if (!EVP_Digest(buf
, qsize
, buf2
, NULL
, evpmd
, NULL
))
183 for (i
= 0; i
< qsize
; i
++)
188 md
[qsize
- 1] |= 0x01;
189 if (!BN_bin2bn(md
, qsize
, q
))
193 r
= BN_is_prime_fasttest_ex(q
, DSS_prime_checks
, ctx
,
194 use_random_seed
, cb
);
200 /* do a callback call */
204 if (!BN_GENCB_call(cb
, 2, 0))
206 if (!BN_GENCB_call(cb
, 3, 0))
213 n
= (bits
- 1) / 160;
216 if ((counter
!= 0) && !BN_GENCB_call(cb
, 0, counter
))
221 /* now 'buf' contains "SEED + offset - 1" */
222 for (k
= 0; k
<= n
; k
++) {
224 * obtain "SEED + offset + k" by incrementing:
226 for (i
= qsize
- 1; i
>= 0; i
--) {
232 if (!EVP_Digest(buf
, qsize
, md
, NULL
, evpmd
, NULL
))
236 if (!BN_bin2bn(md
, qsize
, r0
))
238 if (!BN_lshift(r0
, r0
, (qsize
<< 3) * k
))
240 if (!BN_add(W
, W
, r0
))
245 if (!BN_mask_bits(W
, bits
- 1))
249 if (!BN_add(X
, X
, test
))
253 if (!BN_lshift1(r0
, q
))
255 if (!BN_mod(c
, X
, r0
, ctx
))
257 if (!BN_sub(r0
, c
, BN_value_one()))
259 if (!BN_sub(p
, X
, r0
))
263 if (BN_cmp(p
, test
) >= 0) {
265 r
= BN_is_prime_fasttest_ex(p
, DSS_prime_checks
, ctx
, 1, cb
);
267 goto end
; /* found it */
274 /* "offset = offset + n + 1" */
282 if (!BN_GENCB_call(cb
, 2, 1))
285 /* We now need to generate g */
287 if (!BN_sub(test
, p
, BN_value_one()))
289 if (!BN_div(r0
, NULL
, test
, q
, ctx
))
292 if (!BN_set_word(test
, h
))
294 if (!BN_MONT_CTX_set(mont
, p
, ctx
))
299 if (!BN_mod_exp_mont(g
, test
, r0
, p
, ctx
, mont
))
303 if (!BN_add(test
, test
, BN_value_one()))
308 if (!BN_GENCB_call(cb
, 3, 1))
320 if (ret
->p
== NULL
|| ret
->q
== NULL
|| ret
->g
== NULL
) {
324 if (counter_ret
!= NULL
)
325 *counter_ret
= counter
;
329 memcpy(seed_out
, seed
, qsize
);
334 BN_MONT_CTX_free(mont
);
339 * This is a parameter generation algorithm for the DSA2 algorithm as
340 * described in FIPS 186-3.
343 int dsa_builtin_paramgen2(DSA
*ret
, size_t L
, size_t N
,
344 const EVP_MD
*evpmd
, const unsigned char *seed_in
,
345 size_t seed_len
, int idx
, unsigned char *seed_out
,
346 int *counter_ret
, unsigned long *h_ret
,
350 unsigned char *seed
= NULL
, *seed_tmp
= NULL
;
351 unsigned char md
[EVP_MAX_MD_SIZE
];
353 BIGNUM
*r0
, *W
, *X
, *c
, *test
;
354 BIGNUM
*g
= NULL
, *q
= NULL
, *p
= NULL
;
355 BN_MONT_CTX
*mont
= NULL
;
356 int i
, k
, n
= 0, m
= 0, qsize
= N
>> 3;
360 EVP_MD_CTX
*mctx
= EVP_MD_CTX_new();
370 evpmd
= EVP_sha224();
372 evpmd
= EVP_sha256();
375 mdsize
= EVP_MD_size(evpmd
);
376 /* If unverifiable g generation only don't need seed */
377 if (!ret
->p
|| !ret
->q
|| idx
>= 0) {
381 seed
= OPENSSL_malloc(seed_len
);
386 seed_tmp
= OPENSSL_malloc(seed_len
);
388 if (seed
== NULL
|| seed_tmp
== NULL
)
392 memcpy(seed
, seed_in
, seed_len
);
396 if ((ctx
= BN_CTX_new()) == NULL
)
399 if ((mont
= BN_MONT_CTX_new()) == NULL
)
403 r0
= BN_CTX_get(ctx
);
408 test
= BN_CTX_get(ctx
);
412 /* if p, q already supplied generate g only */
413 if (ret
->p
&& ret
->q
) {
417 memcpy(seed_tmp
, seed
, seed_len
);
424 if (!BN_lshift(test
, BN_value_one(), L
- 1))
427 for (;;) { /* find q */
430 if (!BN_GENCB_call(cb
, 0, m
++))
434 if (RAND_bytes(seed
, seed_len
) <= 0)
438 if (!EVP_Digest(seed
, seed_len
, md
, NULL
, evpmd
, NULL
))
440 /* Take least significant bits of md */
442 pmd
= md
+ mdsize
- qsize
;
447 memset(md
+ mdsize
, 0, qsize
- mdsize
);
451 pmd
[qsize
- 1] |= 0x01;
452 if (!BN_bin2bn(pmd
, qsize
, q
))
456 r
= BN_is_prime_fasttest_ex(q
, DSS_prime_checks
, ctx
,
457 seed_in
? 1 : 0, cb
);
462 /* Provided seed didn't produce a prime: error */
465 DSAerr(DSA_F_DSA_BUILTIN_PARAMGEN2
, DSA_R_Q_NOT_PRIME
);
469 /* do a callback call */
472 /* Copy seed to seed_out before we mess with it */
474 memcpy(seed_out
, seed
, seed_len
);
476 if (!BN_GENCB_call(cb
, 2, 0))
478 if (!BN_GENCB_call(cb
, 3, 0))
485 n
= (L
- 1) / (mdsize
<< 3);
488 if ((counter
!= 0) && !BN_GENCB_call(cb
, 0, counter
))
493 /* now 'buf' contains "SEED + offset - 1" */
494 for (k
= 0; k
<= n
; k
++) {
496 * obtain "SEED + offset + k" by incrementing:
498 for (i
= seed_len
- 1; i
>= 0; i
--) {
504 if (!EVP_Digest(seed
, seed_len
, md
, NULL
, evpmd
, NULL
))
508 if (!BN_bin2bn(md
, mdsize
, r0
))
510 if (!BN_lshift(r0
, r0
, (mdsize
<< 3) * k
))
512 if (!BN_add(W
, W
, r0
))
517 if (!BN_mask_bits(W
, L
- 1))
521 if (!BN_add(X
, X
, test
))
525 if (!BN_lshift1(r0
, q
))
527 if (!BN_mod(c
, X
, r0
, ctx
))
529 if (!BN_sub(r0
, c
, BN_value_one()))
531 if (!BN_sub(p
, X
, r0
))
535 if (BN_cmp(p
, test
) >= 0) {
537 r
= BN_is_prime_fasttest_ex(p
, DSS_prime_checks
, ctx
, 1, cb
);
539 goto end
; /* found it */
546 /* "offset = offset + n + 1" */
549 if (counter
>= (int)(4 * L
))
554 DSAerr(DSA_F_DSA_BUILTIN_PARAMGEN2
, DSA_R_INVALID_PARAMETERS
);
559 if (!BN_GENCB_call(cb
, 2, 1))
564 /* We now need to generate g */
566 if (!BN_sub(test
, p
, BN_value_one()))
568 if (!BN_div(r0
, NULL
, test
, q
, ctx
))
572 if (!BN_set_word(test
, h
))
576 if (!BN_MONT_CTX_set(mont
, p
, ctx
))
580 static const unsigned char ggen
[4] = { 0x67, 0x67, 0x65, 0x6e };
583 md
[1] = (h
>> 8) & 0xff;
585 if (!EVP_DigestInit_ex(mctx
, evpmd
, NULL
))
587 if (!EVP_DigestUpdate(mctx
, seed_tmp
, seed_len
))
589 if (!EVP_DigestUpdate(mctx
, ggen
, sizeof(ggen
)))
591 if (!EVP_DigestUpdate(mctx
, md
, 3))
593 if (!EVP_DigestFinal_ex(mctx
, md
, NULL
))
595 if (!BN_bin2bn(md
, mdsize
, test
))
599 if (!BN_mod_exp_mont(g
, test
, r0
, p
, ctx
, mont
))
603 if (idx
< 0 && !BN_add(test
, test
, BN_value_one()))
606 if (idx
>= 0 && h
> 0xffff)
610 if (!BN_GENCB_call(cb
, 3, 1))
626 if (ret
->p
== NULL
|| ret
->q
== NULL
|| ret
->g
== NULL
) {
630 if (counter_ret
!= NULL
)
631 *counter_ret
= counter
;
636 if (seed_out
!= seed_tmp
)
637 OPENSSL_free(seed_tmp
);
641 BN_MONT_CTX_free(mont
);
642 EVP_MD_CTX_free(mctx
);