1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis */
2 /* SPDX-License-Identifier: Unlicense */
3 #include "tomcrypt_private.h"
4
5 /**
6 @file rsa_import.c
7 Import an RSA key from a X.509 certificate, Steffen Jaeckel
8 */
9
10 #ifdef LTC_MRSA
11
s_rsa_decode(const unsigned char * in,unsigned long inlen,rsa_key * key)12 static int s_rsa_decode(const unsigned char *in, unsigned long inlen, rsa_key *key)
13 {
14 /* now it should be SEQUENCE { INTEGER, INTEGER } */
15 return der_decode_sequence_multi(in, inlen,
16 LTC_ASN1_INTEGER, 1UL, key->N,
17 LTC_ASN1_INTEGER, 1UL, key->e,
18 LTC_ASN1_EOL, 0UL, NULL);
19 }
20
21 /**
22 Import an RSA key from a X.509 certificate
23 @param in The packet to import from
24 @param inlen It's length (octets)
25 @param key [out] Destination for newly imported key
26 @return CRYPT_OK if successful, upon error allocated memory is freed
27 */
rsa_import_x509(const unsigned char * in,unsigned long inlen,rsa_key * key)28 int rsa_import_x509(const unsigned char *in, unsigned long inlen, rsa_key *key)
29 {
30 int err;
31
32 LTC_ARGCHK(in != NULL);
33 LTC_ARGCHK(key != NULL);
34 LTC_ARGCHK(ltc_mp.name != NULL);
35
36 /* init key */
37 if ((err = rsa_init(key)) != CRYPT_OK) {
38 return err;
39 }
40
41 if ((err = x509_decode_public_key_from_certificate(in, inlen,
42 LTC_OID_RSA, LTC_ASN1_NULL,
43 NULL, NULL,
44 (public_key_decode_cb)s_rsa_decode, key)) != CRYPT_OK) {
45 rsa_free(key);
46 } else {
47 key->type = PK_PUBLIC;
48 }
49
50 return err;
51 }
52
53 #endif /* LTC_MRSA */
54
55