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comparison libtomcrypt/src/pk/rsa/rsa_import.c @ 399:a707e6148060

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merge of '5fdf69ca60d1683cdd9f4c2595134bed26394834' and '6b61c50f4cf888bea302ac8fcf5dbb573b443251'
author Matt Johnston <matt@ucc.asn.au>
date Sat, 03 Feb 2007 08:20:34 +0000
parents 0cbe8f6dbf9e
children f849a5ca2efc
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394:17d097fc111c 399:a707e6148060
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.com
10 */
11 #include "tomcrypt.h"
12
13 /**
14 @file rsa_import.c
15 Import a PKCS RSA key, Tom St Denis
16 */
17
18 #ifdef MRSA
19
20 /**
21 Import an RSAPublicKey or RSAPrivateKey [two-prime only, only support >= 1024-bit keys, defined in PKCS #1 v2.1]
22 @param in The packet to import from
23 @param inlen It's length (octets)
24 @param key [out] Destination for newly imported key
25 @return CRYPT_OK if successful, upon error allocated memory is freed
26 */
27 int rsa_import(const unsigned char *in, unsigned long inlen, rsa_key *key)
28 {
29 int err;
30 void *zero;
31 unsigned char *tmpbuf;
32 unsigned long t, x, y, z, tmpoid[16];
33 ltc_asn1_list ssl_pubkey_hashoid[2];
34 ltc_asn1_list ssl_pubkey[2];
35
36 LTC_ARGCHK(in != NULL);
37 LTC_ARGCHK(key != NULL);
38 LTC_ARGCHK(ltc_mp.name != NULL);
39
40 /* init key */
41 if ((err = mp_init_multi(&key->e, &key->d, &key->N, &key->dQ,
42 &key->dP, &key->qP, &key->p, &key->q, NULL)) != CRYPT_OK) {
43 return err;
44 }
45
46 /* see if the OpenSSL DER format RSA public key will work */
47 tmpbuf = XCALLOC(1, MAX_RSA_SIZE*8);
48 if (tmpbuf == NULL) {
49 err = CRYPT_MEM;
50 goto LBL_ERR;
51 }
52
53 /* this includes the internal hash ID and optional params (NULL in this case) */
54 LTC_SET_ASN1(ssl_pubkey_hashoid, 0, LTC_ASN1_OBJECT_IDENTIFIER, tmpoid, sizeof(tmpoid)/sizeof(tmpoid[0]));
55 LTC_SET_ASN1(ssl_pubkey_hashoid, 1, LTC_ASN1_NULL, NULL, 0);
56
57 /* the actual format of the SSL DER key is odd, it stores a RSAPublicKey in a **BIT** string ... so we have to extract it
58 then proceed to convert bit to octet
59 */
60 LTC_SET_ASN1(ssl_pubkey, 0, LTC_ASN1_SEQUENCE, &ssl_pubkey_hashoid, 2);
61 LTC_SET_ASN1(ssl_pubkey, 1, LTC_ASN1_BIT_STRING, tmpbuf, MAX_RSA_SIZE*8);
62
63 if (der_decode_sequence(in, inlen,
64 ssl_pubkey, 2UL) == CRYPT_OK) {
65
66 /* ok now we have to reassemble the BIT STRING to an OCTET STRING. Thanks OpenSSL... */
67 for (t = y = z = x = 0; x < ssl_pubkey[1].size; x++) {
68 y = (y << 1) | tmpbuf[x];
69 if (++z == 8) {
70 tmpbuf[t++] = (unsigned char)y;
71 y = 0;
72 z = 0;
73 }
74 }
75
76 /* now it should be SEQUENCE { INTEGER, INTEGER } */
77 if ((err = der_decode_sequence_multi(tmpbuf, t,
78 LTC_ASN1_INTEGER, 1UL, key->N,
79 LTC_ASN1_INTEGER, 1UL, key->e,
80 LTC_ASN1_EOL, 0UL, NULL)) != CRYPT_OK) {
81 XFREE(tmpbuf);
82 goto LBL_ERR;
83 }
84 XFREE(tmpbuf);
85 key->type = PK_PUBLIC;
86 return CRYPT_OK;
87 }
88 XFREE(tmpbuf);
89
90 /* not SSL public key, try to match against PKCS #1 standards */
91 if ((err = der_decode_sequence_multi(in, inlen,
92 LTC_ASN1_INTEGER, 1UL, key->N,
93 LTC_ASN1_EOL, 0UL, NULL)) != CRYPT_OK) {
94 goto LBL_ERR;
95 }
96
97 if (mp_cmp_d(key->N, 0) == LTC_MP_EQ) {
98 if ((err = mp_init(&zero)) != CRYPT_OK) {
99 goto LBL_ERR;
100 }
101 /* it's a private key */
102 if ((err = der_decode_sequence_multi(in, inlen,
103 LTC_ASN1_INTEGER, 1UL, zero,
104 LTC_ASN1_INTEGER, 1UL, key->N,
105 LTC_ASN1_INTEGER, 1UL, key->e,
106 LTC_ASN1_INTEGER, 1UL, key->d,
107 LTC_ASN1_INTEGER, 1UL, key->p,
108 LTC_ASN1_INTEGER, 1UL, key->q,
109 LTC_ASN1_INTEGER, 1UL, key->dP,
110 LTC_ASN1_INTEGER, 1UL, key->dQ,
111 LTC_ASN1_INTEGER, 1UL, key->qP,
112 LTC_ASN1_EOL, 0UL, NULL)) != CRYPT_OK) {
113 mp_clear(zero);
114 goto LBL_ERR;
115 }
116 mp_clear(zero);
117 key->type = PK_PRIVATE;
118 } else if (mp_cmp_d(key->N, 1) == LTC_MP_EQ) {
119 /* we don't support multi-prime RSA */
120 err = CRYPT_PK_INVALID_TYPE;
121 goto LBL_ERR;
122 } else {
123 /* it's a public key and we lack e */
124 if ((err = der_decode_sequence_multi(in, inlen,
125 LTC_ASN1_INTEGER, 1UL, key->N,
126 LTC_ASN1_INTEGER, 1UL, key->e,
127 LTC_ASN1_EOL, 0UL, NULL)) != CRYPT_OK) {
128 goto LBL_ERR;
129 }
130 key->type = PK_PUBLIC;
131 }
132 return CRYPT_OK;
133 LBL_ERR:
134 mp_clear_multi(key->d, key->e, key->N, key->dQ, key->dP, key->qP, key->p, key->q, NULL);
135 return err;
136 }
137
138 #endif /* MRSA */
139
140
141 /* $Source: /cvs/libtom/libtomcrypt/src/pk/rsa/rsa_import.c,v $ */
142 /* $Revision: 1.21 $ */
143 /* $Date: 2006/12/04 22:23:27 $ */