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comparison src/pk/dsa/dsa_export.c @ 191:1c15b283127b libtomcrypt-orig

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Import of libtomcrypt 1.02 with manual path rename rearrangement etc
author Matt Johnston <matt@ucc.asn.au>
date Fri, 06 May 2005 13:23:02 +0000
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children 39d5d58461d6
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143:5d99163f7e32 191:1c15b283127b
1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis
2 *
3 * LibTomCrypt is a library that provides various cryptographic
4 * algorithms in a highly modular and flexible manner.
5 *
6 * The library is free for all purposes without any express
7 * guarantee it works.
8 *
9 * Tom St Denis, [email protected], http://libtomcrypt.org
10 */
11 #include "tomcrypt.h"
12
13 /**
14 @file dsa_export.c
15 DSA implementation, export key, Tom St Denis
16 */
17
18 #ifdef MDSA
19
20 /**
21 Export a DSA key to a binary packet
22 @param out [out] Where to store the packet
23 @param outlen [in/out] The max size and resulting size of the packet
24 @param type The type of key to export (PK_PRIVATE or PK_PUBLIC)
25 @param key The key to export
26 @return CRYPT_OK if successful
27 */
28 int dsa_export(unsigned char *out, unsigned long *outlen, int type, dsa_key *key)
29 {
30 unsigned long y, z;
31 int err;
32
33 LTC_ARGCHK(out != NULL);
34 LTC_ARGCHK(outlen != NULL);
35 LTC_ARGCHK(key != NULL);
36
37 /* can we store the static header? */
38 if (*outlen < (PACKET_SIZE + 1 + 2)) {
39 return CRYPT_BUFFER_OVERFLOW;
40 }
41
42 if (type == PK_PRIVATE && key->type != PK_PRIVATE) {
43 return CRYPT_PK_TYPE_MISMATCH;
44 }
45
46 if (type != PK_PUBLIC && type != PK_PRIVATE) {
47 return CRYPT_INVALID_ARG;
48 }
49
50 /* store header */
51 packet_store_header(out, PACKET_SECT_DSA, PACKET_SUB_KEY);
52 y = PACKET_SIZE;
53
54 /* store g, p, q, qord */
55 out[y++] = type;
56 out[y++] = (key->qord>>8)&255;
57 out[y++] = key->qord & 255;
58
59 OUTPUT_BIGNUM(&key->g,out,y,z);
60 OUTPUT_BIGNUM(&key->p,out,y,z);
61 OUTPUT_BIGNUM(&key->q,out,y,z);
62
63 /* public exponent */
64 OUTPUT_BIGNUM(&key->y,out,y,z);
65
66 if (type == PK_PRIVATE) {
67 OUTPUT_BIGNUM(&key->x,out,y,z);
68 }
69
70 *outlen = y;
71 return CRYPT_OK;
72 }
73
74 #endif
75