1 /*
2  * Copyright 2007-2016 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the OpenSSL license (the "License").  You may not use
5  * this file except in compliance with the License.  You can obtain a copy
6  * in the file LICENSE in the source distribution or at
7  * https://www.openssl.org/source/license.html
8  */
9 
10 #include <openssl/dsa.h>
11 #include "internal/refcount.h"
12 
13 struct dsa_st {
14     /*
15      * This first variable is used to pick up errors where a DSA is passed
16      * instead of of a EVP_PKEY
17      */
18     int pad;
19     int32_t version;
20     BIGNUM *p;
21     BIGNUM *q;                  /* == 20 */
22     BIGNUM *g;
23     BIGNUM *pub_key;            /* y public key */
24     BIGNUM *priv_key;           /* x private key */
25     int flags;
26     /* Normally used to cache montgomery values */
27     BN_MONT_CTX *method_mont_p;
28     CRYPTO_REF_COUNT references;
29     CRYPTO_EX_DATA ex_data;
30     const DSA_METHOD *meth;
31     /* functional reference if 'meth' is ENGINE-provided */
32     ENGINE *engine;
33     CRYPTO_RWLOCK *lock;
34 };
35 
36 struct DSA_SIG_st {
37     BIGNUM *r;
38     BIGNUM *s;
39 };
40 
41 struct dsa_method {
42     char *name;
43     DSA_SIG *(*dsa_do_sign) (const unsigned char *dgst, int dlen, DSA *dsa);
44     int (*dsa_sign_setup) (DSA *dsa, BN_CTX *ctx_in, BIGNUM **kinvp,
45                            BIGNUM **rp);
46     int (*dsa_do_verify) (const unsigned char *dgst, int dgst_len,
47                           DSA_SIG *sig, DSA *dsa);
48     int (*dsa_mod_exp) (DSA *dsa, BIGNUM *rr, const BIGNUM *a1,
49                         const BIGNUM *p1, const BIGNUM *a2, const BIGNUM *p2,
50                         const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *in_mont);
51     /* Can be null */
52     int (*bn_mod_exp) (DSA *dsa, BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
53                        const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx);
54     int (*init) (DSA *dsa);
55     int (*finish) (DSA *dsa);
56     int flags;
57     void *app_data;
58     /* If this is non-NULL, it is used to generate DSA parameters */
59     int (*dsa_paramgen) (DSA *dsa, int bits,
60                          const unsigned char *seed, int seed_len,
61                          int *counter_ret, unsigned long *h_ret,
62                          BN_GENCB *cb);
63     /* If this is non-NULL, it is used to generate DSA keys */
64     int (*dsa_keygen) (DSA *dsa);
65 };
66 
67 int dsa_builtin_paramgen(DSA *ret, size_t bits, size_t qbits,
68                          const EVP_MD *evpmd, const unsigned char *seed_in,
69                          size_t seed_len, unsigned char *seed_out,
70                          int *counter_ret, unsigned long *h_ret,
71                          BN_GENCB *cb);
72 
73 int dsa_builtin_paramgen2(DSA *ret, size_t L, size_t N,
74                           const EVP_MD *evpmd, const unsigned char *seed_in,
75                           size_t seed_len, int idx, unsigned char *seed_out,
76                           int *counter_ret, unsigned long *h_ret,
77                           BN_GENCB *cb);
78