summaryrefslogtreecommitdiffstats
path: root/crypto/userspace/libtomcrypt/pk/rsa/rsa_export.c
blob: c5e8ff0a65d71b7a2e1d258dc73dad490ccada51 (plain)
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
/* 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.
 *
 * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
 */
#include "tomcrypt.h"
#include <ncr-int.h>
#include <linux/slab.h>
/**
  @file rsa_export.c
  Export RSA LTC_PKCS keys, Tom St Denis
*/  

#ifdef LTC_MRSA

/**
    This will export either an RSAPublicKey or RSAPrivateKey [defined in LTC_PKCS #1 v2.1] 
    @param out       [out] Destination of the packet
    @param outlen    [in/out] The max size and resulting size of the packet
    @param type      The type of exported key (PK_PRIVATE or PK_PUBLIC)
    @param key       The RSA key to export
    @return CRYPT_OK if successful
*/    
int rsa_export(unsigned char *out, unsigned long *outlen, int type, rsa_key *key)
{
   unsigned long zero=0;
   int err;
   LTC_ARGCHK(out    != NULL);
   LTC_ARGCHK(outlen != NULL);
   LTC_ARGCHK(key    != NULL);

   /* type valid? */
   if (!(key->type == PK_PRIVATE) && (type == PK_PRIVATE)) {
      return CRYPT_PK_INVALID_TYPE;
   }

   if (type == PK_PRIVATE) {
      /* private key */
      /* output is 
            Version, n, e, d, p, q, d mod (p-1), d mod (q - 1), 1/q mod p
       */
      return der_encode_sequence_multi(out, outlen, 
                          LTC_ASN1_SHORT_INTEGER, 1UL, &zero, 
                          LTC_ASN1_INTEGER, 1UL,  &key->N, 
                          LTC_ASN1_INTEGER, 1UL,  &key->e,
                          LTC_ASN1_INTEGER, 1UL,  &key->d, 
                          LTC_ASN1_INTEGER, 1UL,  &key->p, 
                          LTC_ASN1_INTEGER, 1UL,  &key->q, 
                          LTC_ASN1_INTEGER, 1UL,  &key->dP,
                          LTC_ASN1_INTEGER, 1UL,  &key->dQ, 
                          LTC_ASN1_INTEGER, 1UL,  &key->qP, 
                          LTC_ASN1_EOL,     0UL, NULL);
   } else {
      unsigned long tmplen = (mp_count_bits(&key->N)/8)*2+8;
      unsigned char* tmp = XMALLOC(tmplen);
      
      if (tmp == NULL) {
	   return CRYPT_MEM;
      }

      err = der_encode_sequence_multi(tmp, &tmplen, 
                                 LTC_ASN1_INTEGER, 1UL,  &key->N, 
                                 LTC_ASN1_INTEGER, 1UL,  &key->e, 
                                 LTC_ASN1_EOL,     0UL, NULL);
      if (err != CRYPT_OK) {
		  goto error;
      }

      err = der_encode_subject_public_key_info(out, outlen, 
        PKA_RSA, tmp, tmplen, LTC_ASN1_NULL, NULL, 0);
      
error:
      XFREE(tmp);
      return err;
   }
}

#endif /* LTC_MRSA */

/* $Source: /cvs/libtom/libtomcrypt/src/pk/rsa/rsa_export.c,v $ */
/* $Revision: 1.17 $ */
/* $Date: 2007/05/12 14:32:35 $ */