1 // SPDX-License-Identifier: BSD-2-Clause
2 /* LibTomCrypt, modular cryptographic library -- Tom St Denis
3  *
4  * LibTomCrypt is a library that provides various cryptographic
5  * algorithms in a highly modular and flexible manner.
6  *
7  * The library is free for all purposes without any express
8  * guarantee it works.
9  */
10 #include "tomcrypt_private.h"
11 
12 /**
13   @file rsa_import.c
14   Import an RSA key from a X.509 certificate, Steffen Jaeckel
15 */
16 
17 #ifdef LTC_MRSA
18 
_rsa_decode(const unsigned char * in,unsigned long inlen,rsa_key * key)19 static int _rsa_decode(const unsigned char *in, unsigned long inlen, rsa_key *key)
20 {
21    /* now it should be SEQUENCE { INTEGER, INTEGER } */
22    return der_decode_sequence_multi(in, inlen,
23                                         LTC_ASN1_INTEGER, 1UL, key->N,
24                                         LTC_ASN1_INTEGER, 1UL, key->e,
25                                         LTC_ASN1_EOL,     0UL, NULL);
26 }
27 
28 /**
29   Import an RSA key from a X.509 certificate
30   @param in      The packet to import from
31   @param inlen   It's length (octets)
32   @param key     [out] Destination for newly imported key
33   @return CRYPT_OK if successful, upon error allocated memory is freed
34 */
rsa_import_x509(const unsigned char * in,unsigned long inlen,rsa_key * key)35 int rsa_import_x509(const unsigned char *in, unsigned long inlen, rsa_key *key)
36 {
37    int           err;
38 
39    LTC_ARGCHK(in          != NULL);
40    LTC_ARGCHK(key         != NULL);
41    LTC_ARGCHK(ltc_mp.name != NULL);
42 
43    /* init key */
44    if ((err = mp_init_multi(&key->e, &key->d, &key->N, &key->dQ,
45                             &key->dP, &key->qP, &key->p, &key->q, NULL)) != CRYPT_OK) {
46       return err;
47    }
48 
49    if ((err = x509_decode_public_key_from_certificate(in, inlen,
50                                                       PKA_RSA, LTC_ASN1_NULL,
51                                                       NULL, NULL,
52                                                       (public_key_decode_cb)_rsa_decode, key)) != CRYPT_OK) {
53       rsa_free(key);
54    } else {
55       key->type = PK_PUBLIC;
56    }
57 
58    return err;
59 }
60 
61 #endif /* LTC_MRSA */
62 
63 
64 /* ref:         $Format:%D$ */
65 /* git commit:  $Format:%H$ */
66 /* commit time: $Format:%ai$ */
67