add possibility to rsa_import() the public key of an x.509 certificate

This commit is contained in:
Steffen Jaeckel 2015-09-10 23:29:10 +02:00
parent 2e822a80a8
commit f9bce83329

View File

@ -29,7 +29,8 @@ int rsa_import(const unsigned char *in, unsigned long inlen, rsa_key *key)
int err;
void *zero;
unsigned char *tmpbuf=NULL;
unsigned long tmpbuf_len;
unsigned long tmpbuf_len, tmp_inlen;
ltc_asn1_list *decoded_list = NULL, *l;
LTC_ARGCHK(in != NULL);
LTC_ARGCHK(key != NULL);
@ -53,6 +54,53 @@ int rsa_import(const unsigned char *in, unsigned long inlen, rsa_key *key)
PKA_RSA, tmpbuf, &tmpbuf_len,
LTC_ASN1_NULL, NULL, 0);
tmp_inlen = inlen;
if (err != CRYPT_OK &&
der_decode_sequence_flexi(in, &tmp_inlen, &decoded_list) == CRYPT_OK) {
l = decoded_list;
/* Move 2 levels up in the tree
SEQUENCE
SEQUENCE
...
*/
if (l->type == LTC_ASN1_SEQUENCE && l->child) {
l = l->child;
if (l->type == LTC_ASN1_SEQUENCE && l->child) {
l = l->child;
/* Move forward in the tree until we find this combination
...
SEQUENCE
SEQUENCE
OBJECT IDENTIFIER 1.2.840.113549.1.1.1
NULL
BIT STRING
*/
do {
/* The additional check for l->data is there to make sure
* we won't try to decode a list that has been 'shrunk'
*/
if (l->type == LTC_ASN1_SEQUENCE && l->data && l->child &&
l->child->type == LTC_ASN1_SEQUENCE && l->child->child &&
l->child->child->type == LTC_ASN1_OBJECT_IDENTIFIER && l->child->next &&
l->child->next->type == LTC_ASN1_BIT_STRING) {
err = der_decode_subject_public_key_info(l->data, l->size,
PKA_RSA, tmpbuf, &tmpbuf_len,
LTC_ASN1_NULL, NULL, 0);
if (err == CRYPT_OK) {
break;
}
}
l = l->next;
} while(l);
}
}
}
if (decoded_list) {
der_free_sequence_flexi(decoded_list);
}
if (err == CRYPT_OK) { /* SubjectPublicKeyInfo format */
/* now it should be SEQUENCE { INTEGER, INTEGER } */