crypto/dsa/dsa_gen.c

   1 /*
   2  * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (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 /*
  11  * DSA low level APIs are deprecated for public use, but still ok for
  12  * internal use.
  13  */
  14 #include "internal/deprecated.h"
  15
  16 #include <openssl/opensslconf.h>
  17 #include <stdio.h>
  18 #include "internal/cryptlib.h"
  19 #include <openssl/evp.h>
  20 #include <openssl/bn.h>
  21 #include <openssl/rand.h>
  22 #include <openssl/sha.h>
  23 #include "crypto/dsa.h"
  24 #include "dsa_local.h"
  25
  26 int dsa_generate_ffc_parameters(DSA *dsa, int type,
  27                                 int pbits, int qbits,
  28                                 EVP_MD *md, BN_GENCB *cb)
  29 {
  30     int ret = 0, res;
  31
  32     if (qbits <= 0) {
  33         if (md != NULL)
  34             qbits = EVP_MD_size(md) * 8;
  35         else
  36             qbits = (pbits >= 2048 ? SHA256_DIGEST_LENGTH :
  37                                      SHA_DIGEST_LENGTH) * 8;
  38     }
  39 #ifndef FIPS_MODE
  40     if (type == DSA_PARAMGEN_TYPE_FIPS_186_2)
  41         ret = ffc_params_FIPS186_2_generate(dsa->libctx, &dsa->params,
  42                                             FFC_PARAM_TYPE_DSA,
  43                                             pbits, qbits, md, &res, cb);
  44     else
  45 #endif
  46         ret = ffc_params_FIPS186_4_generate(dsa->libctx, &dsa->params,
  47                                             FFC_PARAM_TYPE_DSA,
  48                                             pbits, qbits, md, &res, cb);
  49     if (ret > 0)
  50         dsa->dirty_cnt++;
  51     return ret;
  52 }
  53
  54 #ifndef FIPS_MODE
  55 int DSA_generate_parameters_ex(DSA *dsa, int bits,
  56                                const unsigned char *seed_in, int seed_len,
  57                                int *counter_ret, unsigned long *h_ret,
  58                                BN_GENCB *cb)
  59 {
  60 #ifndef FIPS_MODE
  61     if (dsa->meth->dsa_paramgen)
  62         return dsa->meth->dsa_paramgen(dsa, bits, seed_in, seed_len,
  63                                        counter_ret, h_ret, cb);
  64 #endif
  65     if (seed_in != NULL
  66         && !ffc_params_set_validate_params(&dsa->params, seed_in, seed_len, -1))
  67         return 0;
  68
  69 #ifndef FIPS_MODE
  70     /* The old code used FIPS 186-2 DSA Parameter generation */
  71     if (bits <= 1024 && seed_len == 20) {
  72         if (!dsa_generate_ffc_parameters(dsa, DSA_PARAMGEN_TYPE_FIPS_186_2,
  73                                          bits, 160, NULL, cb))
  74             return 0;
  75     } else
  76 #endif
  77     {
  78         if (!dsa_generate_ffc_parameters(dsa, DSA_PARAMGEN_TYPE_FIPS_186_4,
  79                                          bits, -1, NULL, cb))
  80             return 0;
  81     }
  82
  83     if (counter_ret != NULL)
  84         *counter_ret = dsa->params.pcounter;
  85     if (h_ret != NULL)
  86         *h_ret = dsa->params.h;
  87     return 1;
  88 }
  89 #endif