Introduce generic x509_get_pubkey()
diff --git a/library/x509parse.c b/library/x509parse.c
index e3c363a..6f20919 100644
--- a/library/x509parse.c
+++ b/library/x509parse.c
@@ -571,6 +571,84 @@
return( 0 );
}
+static int x509_get_ecpubkey( unsigned char **p, const unsigned char *end,
+ x509_buf *alg_params, ecp_keypair *key )
+{
+ int ret;
+ ecp_group_id grp_id;
+
+ if( ( ret = x509_ecparams_get_grp_id( alg_params, &grp_id ) ) != 0 )
+ return( ret );
+
+ if( ( ret = ecp_use_known_dp( &key->grp, grp_id ) ) != 0 )
+ return( ret );
+
+ if( ( ret = ecp_point_read_binary( &key->grp, &key->Q,
+ (const unsigned char *) *p, end - *p ) ) != 0 )
+ {
+ return( POLARSSL_ERR_X509_KEY_INVALID_FORMAT + ret );
+ }
+
+ return( 0 );
+}
+
+/*
+ * SubjectPublicKeyInfo ::= SEQUENCE {
+ * algorithm AlgorithmIdentifier,
+ * subjectPublicKey BIT STRING }
+ */
+static int x509_get_pubkey( unsigned char **p,
+ const unsigned char *end,
+ pk_context *pk )
+{
+ int ret;
+ size_t len;
+ x509_buf alg_params;
+ pk_type_t pk_alg = POLARSSL_PK_NONE;
+
+ if( ( ret = asn1_get_tag( p, end, &len,
+ ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
+ {
+ return( POLARSSL_ERR_X509_CERT_INVALID_FORMAT + ret );
+ }
+
+ end = *p + len;
+
+ if( ( ret = x509_get_algid( p, end, &pk_alg, &alg_params ) ) != 0 )
+ return( ret );
+
+ if( ( ret = asn1_get_tag( p, end, &len, ASN1_BIT_STRING ) ) != 0 )
+ return( POLARSSL_ERR_X509_CERT_INVALID_PUBKEY + ret );
+
+ if( ( end - *p ) < 1 )
+ return( POLARSSL_ERR_X509_CERT_INVALID_PUBKEY +
+ POLARSSL_ERR_ASN1_OUT_OF_DATA );
+
+ if( *p + len != end )
+ return( POLARSSL_ERR_X509_CERT_INVALID_PUBKEY +
+ POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
+
+ if( *(*p)++ != 0 )
+ return( POLARSSL_ERR_X509_CERT_INVALID_PUBKEY );
+
+ pk_set_type( pk, pk_alg );
+
+ switch( pk_alg )
+ {
+ case POLARSSL_PK_NONE:
+ return( POLARSSL_ERR_X509_UNKNOWN_PK_ALG );
+
+ case POLARSSL_PK_RSA:
+ return( x509_get_rsapubkey( p, end, pk->data ) );
+
+ case POLARSSL_PK_ECKEY_DH:
+ ((ecp_keypair *) pk->data)->alg = POLARSSL_ECP_KEY_ALG_ECDH;
+ /* FALLTHROUGH */
+ case POLARSSL_PK_ECKEY:
+ return( x509_get_ecpubkey( p, end, &alg_params, pk->data ) );
+ }
+}
+
/*
* SubjectPublicKeyInfo ::= SEQUENCE {
* algorithm AlgorithmIdentifier,