From Code to Community: Sponsoring The Perl and Raku Conference 2025 Learn more

MIK / CryptX-0.059_001 / src / ltc / pk / dsa / dsa_export.c 

            

              
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116

              
/* LibTomCrypt, modular cryptographic library -- Tom St Denis
 *
 * LibTomCrypt is a library that provides various cryptographic
 * algorithms in a highly modular and flexible manner.
 *
 * The library is free for all purposes without any express
 * guarantee it works.
 */
#include "tomcrypt.h"
/**
   @file dsa_export.c
   DSA implementation, export key, Tom St Denis
*/
#ifdef LTC_MDSA
/**
  Export a DSA key to a binary packet
  @param out    [out] Where to store the packet
  @param outlen [in/out] The max size and resulting size of the packet
  @param type   The type of key to export (PK_PRIVATE or PK_PUBLIC)
  @param key    The key to export
  @return CRYPT_OK if successful
*/
int dsa_export(unsigned char *out, unsigned long *outlen, int type, const dsa_key *key)
{
   unsigned long zero=0;
   int err, std;
   LTC_ARGCHK(out    != NULL);
   LTC_ARGCHK(outlen != NULL);
   LTC_ARGCHK(key    != NULL);
   std = type & PK_STD;
   type &= ~PK_STD;
   /* can we store the static header?  */
   if (type == PK_PRIVATE && key->type != PK_PRIVATE) {
      return CRYPT_PK_TYPE_MISMATCH;
   }
   if (type != PK_PUBLIC && type != PK_PRIVATE) {
      return CRYPT_INVALID_ARG;
   }
   if (type == PK_PRIVATE) {
      if (std) {
          return der_encode_sequence_multi(out, outlen,
                                         LTC_ASN1_SHORT_INTEGER, 1UL, &zero,
                                         LTC_ASN1_INTEGER,      1UL, key->p,
                                         LTC_ASN1_INTEGER,      1UL, key->q,
                                         LTC_ASN1_INTEGER,      1UL, key->g,
                                         LTC_ASN1_INTEGER,      1UL, key->y,
                                         LTC_ASN1_INTEGER,      1UL, key->x,
                                         LTC_ASN1_EOL,          0UL, NULL);
      }
      else {
          unsigned char flags[1];
          flags[0] = 1;
          return der_encode_sequence_multi(out, outlen,
                                         LTC_ASN1_BIT_STRING,   1UL, flags,
                                         LTC_ASN1_INTEGER,      1UL, key->g,
                                         LTC_ASN1_INTEGER,      1UL, key->p,
                                         LTC_ASN1_INTEGER,      1UL, key->q,
                                         LTC_ASN1_INTEGER,      1UL, key->y,
                                         LTC_ASN1_INTEGER,      1UL, key->x,
                                         LTC_ASN1_EOL,          0UL, NULL);
      }
   } else {
      if (std) {
          unsigned long tmplen = (unsigned long)(mp_count_bits(key->y) / 8) + 8;
          unsigned char* tmp = XMALLOC(tmplen);
          ltc_asn1_list int_list[3];
          if (tmp == NULL) {
              return CRYPT_MEM;
          }
          err = der_encode_integer(key->y, tmp, &tmplen);
          if (err != CRYPT_OK) {
              goto error;
          }
          LTC_SET_ASN1(int_list, 0, LTC_ASN1_INTEGER, key->p, 1UL);
          LTC_SET_ASN1(int_list, 1, LTC_ASN1_INTEGER, key->q, 1UL);
          LTC_SET_ASN1(int_list, 2, LTC_ASN1_INTEGER, key->g, 1UL);
          err = x509_encode_subject_public_key_info(out, outlen, PKA_DSA, tmp,
              tmplen, LTC_ASN1_SEQUENCE, int_list,
              sizeof(int_list) / sizeof(int_list[0]));
error:
          XFREE(tmp);
          return err;
      }
      else {
          unsigned char flags[1];
          flags[0] = 0;
          return der_encode_sequence_multi(out, outlen,
                                     LTC_ASN1_BIT_STRING,   1UL, flags,
                                     LTC_ASN1_INTEGER,      1UL, key->g,
                                     LTC_ASN1_INTEGER,      1UL, key->p,
                                     LTC_ASN1_INTEGER,      1UL, key->q,
                                     LTC_ASN1_INTEGER,      1UL, key->y,
                                     LTC_ASN1_EOL,          0UL, NULL);
      }
   }
}
#endif
/* ref:         $Format:%D$ */
/* git commit:  $Format:%H$ */
/* commit time: $Format:%ai$ */