/*
* Copyright (C) 2003-2012 Free Software Foundation, Inc.
* Copyright (C) 2015-2017 Red Hat, Inc.
*
* Author: Nikos Mavrogiannopoulos
*
* This file is part of GnuTLS.
*
* The GnuTLS is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>
*
*/
#include "gnutls_int.h"
#include "errors.h"
#include <global.h>
#include <libtasn1.h>
#include <datum.h>
#include "common.h"
#include "x509_int.h"
#include <num.h>
#include <limits.h>
/* Reads an Integer from the DER encoded data
*/
int _gnutls_x509_read_der_int(uint8_t * der, int dersize, bigint_t * out)
{
int result;
ASN1_TYPE spk = ASN1_TYPE_EMPTY;
/* == INTEGER */
if ((result = asn1_create_element
(_gnutls_get_gnutls_asn(), "GNUTLS.DSAPublicKey",
&spk)) != ASN1_SUCCESS) {
gnutls_assert();
return _gnutls_asn2err(result);
}
result = _asn1_strict_der_decode(&spk, der, dersize, NULL);
if (result != ASN1_SUCCESS) {
gnutls_assert();
asn1_delete_structure(&spk);
return _gnutls_asn2err(result);
}
/* Read Y */
if ((result = _gnutls_x509_read_int(spk, "", out)) < 0) {
gnutls_assert();
asn1_delete_structure(&spk);
return _gnutls_asn2err(result);
}
asn1_delete_structure(&spk);
return 0;
}
int _gnutls_x509_read_der_uint(uint8_t * der, int dersize, unsigned int *out)
{
int result;
ASN1_TYPE spk = ASN1_TYPE_EMPTY;
/* == INTEGER */
if ((result = asn1_create_element
(_gnutls_get_gnutls_asn(), "GNUTLS.DSAPublicKey",
&spk)) != ASN1_SUCCESS) {
gnutls_assert();
return _gnutls_asn2err(result);
}
result = _asn1_strict_der_decode(&spk, der, dersize, NULL);
if (result != ASN1_SUCCESS) {
gnutls_assert();
asn1_delete_structure(&spk);
return _gnutls_asn2err(result);
}
/* Read Y */
if ((result = _gnutls_x509_read_uint(spk, "", out)) < 0) {
gnutls_assert();
asn1_delete_structure(&spk);
return _gnutls_asn2err(result);
}
asn1_delete_structure(&spk);
return 0;
}
/* Extracts DSA and RSA parameters from a certificate.
*/
int
_gnutls_get_asn_mpis(ASN1_TYPE asn, const char *root,
gnutls_pk_params_st * params)
{
int result;
char name[256];
gnutls_datum_t tmp = { NULL, 0 };
gnutls_pk_algorithm_t pk_algorithm;
gnutls_ecc_curve_t curve;
gnutls_pk_params_init(params);
result = _gnutls_x509_get_pk_algorithm(asn, root, &curve, NULL);
if (result < 0) {
gnutls_assert();
return result;
}
pk_algorithm = result;
params->curve = curve;
params->algo = pk_algorithm;
/* Read the algorithm's parameters
*/
_asnstr_append_name(name, sizeof(name), root,
".algorithm.parameters");
if (pk_algorithm != GNUTLS_PK_RSA &&
pk_algorithm != GNUTLS_PK_EDDSA_ED25519 && pk_algorithm != GNUTLS_PK_ECDH_X25519 &&
pk_algorithm != GNUTLS_PK_EDDSA_ED448 && pk_algorithm != GNUTLS_PK_ECDH_X448) {
/* RSA and EdDSA do not use parameters */
result = _gnutls_x509_read_value(asn, name, &tmp);
if (pk_algorithm == GNUTLS_PK_RSA_PSS &&
(result == GNUTLS_E_ASN1_VALUE_NOT_FOUND || result == GNUTLS_E_ASN1_ELEMENT_NOT_FOUND)) {
goto skip_params;
}
if (result < 0) {
gnutls_assert();
goto error;
}
result =
_gnutls_x509_read_pubkey_params(pk_algorithm,
tmp.data, tmp.size,
params);
if (result < 0) {
gnutls_assert();
goto error;
}
_gnutls_free_datum(&tmp);
}
skip_params:
/* Now read the public key */
_asnstr_append_name(name, sizeof(name), root, ".subjectPublicKey");
result = _gnutls_x509_read_value(asn, name, &tmp);
if (result < 0) {
gnutls_assert();
goto error;
}
if ((result =
_gnutls_x509_read_pubkey(pk_algorithm, tmp.data, tmp.size,
params)) < 0) {
gnutls_assert();
goto error;
}
result = _gnutls_x509_check_pubkey_params(params);
if (result < 0) {
gnutls_assert();
goto error;
}
result = 0;
error:
if (result < 0)
gnutls_pk_params_release(params);
_gnutls_free_datum(&tmp);
return result;
}
/* Extracts DSA and RSA parameters from a certificate.
*/
int
_gnutls_x509_crt_get_mpis(gnutls_x509_crt_t cert,
gnutls_pk_params_st * params)
{
/* Read the algorithm's OID
*/
return _gnutls_get_asn_mpis(cert->cert,
"tbsCertificate.subjectPublicKeyInfo",
params);
}
/* Extracts DSA and RSA parameters from a certificate.
*/
int
_gnutls_x509_crq_get_mpis(gnutls_x509_crq_t cert,
gnutls_pk_params_st * params)
{
/* Read the algorithm's OID
*/
return _gnutls_get_asn_mpis(cert->crq,
"certificationRequestInfo.subjectPKInfo",
params);
}
/*
* This function reads and decodes the parameters for DSS or RSA keys.
* This is the "signatureAlgorithm" fields.
*/
int
_gnutls_x509_read_pkalgo_params(ASN1_TYPE src, const char *src_name,
gnutls_x509_spki_st *spki, unsigned is_sig)
{
int result;
char name[128];
char oid[MAX_OID_SIZE];
int oid_size;
memset(spki, 0, sizeof(*spki));
_gnutls_str_cpy(name, sizeof(name), src_name);
_gnutls_str_cat(name, sizeof(name), ".algorithm");
oid_size = sizeof(oid);
result = asn1_read_value(src, name, oid, &oid_size);
if (result != ASN1_SUCCESS) {
gnutls_assert();
return _gnutls_asn2err(result);
}
if (strcmp (oid, PK_PKIX1_RSA_PSS_OID) == 0) {
gnutls_datum_t tmp = { NULL, 0 };
_gnutls_str_cpy(name, sizeof(name), src_name);
_gnutls_str_cat(name, sizeof(name), ".parameters");
result = _gnutls_x509_read_value(src, name, &tmp);
if (result < 0) {
if (!is_sig) {
if (result == GNUTLS_E_ASN1_ELEMENT_NOT_FOUND ||
result != GNUTLS_E_ASN1_VALUE_NOT_FOUND) {
/* it is ok to not have parameters in SPKI, but
* not in signatures */
return 0;
}
}
return gnutls_assert_val(result);
}
result = _gnutls_x509_read_rsa_pss_params(tmp.data, tmp.size,
spki);
_gnutls_free_datum(&tmp);
if (result < 0)
gnutls_assert();
return result;
}
return 0;
}
static int write_oid_and_params(ASN1_TYPE dst, const char *dst_name, const char *oid, gnutls_x509_spki_st *params)
{
int result;
char name[128];
if (params == NULL) {
gnutls_assert();
return GNUTLS_E_INVALID_REQUEST;
}
_gnutls_str_cpy(name, sizeof(name), dst_name);
_gnutls_str_cat(name, sizeof(name), ".algorithm");
/* write the OID.
*/
result = asn1_write_value(dst, name, oid, 1);
if (result != ASN1_SUCCESS) {
gnutls_assert();
return _gnutls_asn2err(result);
}
_gnutls_str_cpy(name, sizeof(name), dst_name);
_gnutls_str_cat(name, sizeof(name), ".parameters");
if (params->pk == GNUTLS_PK_RSA)
result =
asn1_write_value(dst, name, ASN1_NULL, ASN1_NULL_SIZE);
else if (params->pk == GNUTLS_PK_RSA_PSS) {
gnutls_datum_t tmp = { NULL, 0 };
result = _gnutls_x509_write_rsa_pss_params(params, &tmp);
if (result < 0)
return gnutls_assert_val(result);
result = asn1_write_value(dst, name, tmp.data, tmp.size);
_gnutls_free_datum(&tmp);
} else
result = asn1_write_value(dst, name, NULL, 0);
if (result != ASN1_SUCCESS && result != ASN1_ELEMENT_NOT_FOUND) {
/* Here we ignore the element not found error, since this
* may have been disabled before.
*/
gnutls_assert();
return _gnutls_asn2err(result);
}
return 0;
}
int
_gnutls_x509_write_spki_params(ASN1_TYPE dst, const char *dst_name,
gnutls_x509_spki_st *params)
{
const char *oid;
if (params->legacy && params->pk == GNUTLS_PK_RSA)
oid = PK_PKIX1_RSA_OID;
else if (params->pk == GNUTLS_PK_RSA_PSS)
oid = PK_PKIX1_RSA_PSS_OID;
else
oid = gnutls_pk_get_oid(params->pk);
if (oid == NULL) {
gnutls_assert();
_gnutls_debug_log
("Cannot find OID for public key algorithm %s\n",
gnutls_pk_get_name(params->pk));
return GNUTLS_E_INVALID_REQUEST;
}
return write_oid_and_params(dst, dst_name, oid, params);
}
int
_gnutls_x509_write_sign_params(ASN1_TYPE dst, const char *dst_name,
const gnutls_sign_entry_st *se, gnutls_x509_spki_st *params)
{
const char *oid;
if (params->legacy && params->pk == GNUTLS_PK_RSA)
oid = PK_PKIX1_RSA_OID;
else if (params->pk == GNUTLS_PK_RSA_PSS)
oid = PK_PKIX1_RSA_PSS_OID;
else
oid = se->oid;
if (oid == NULL) {
gnutls_assert();
_gnutls_debug_log
("Cannot find OID for sign algorithm %s\n",
se->name);
return GNUTLS_E_INVALID_REQUEST;
}
return write_oid_and_params(dst, dst_name, oid, params);
}
/* this function reads a (small) unsigned integer
* from asn1 structs. Combines the read and the conversion
* steps.
*/
int
_gnutls_x509_read_uint(ASN1_TYPE node, const char *value,
unsigned int *ret)
{
int len, result;
uint8_t *tmpstr;
len = 0;
result = asn1_read_value(node, value, NULL, &len);
if (result != ASN1_MEM_ERROR) {
return _gnutls_asn2err(result);
}
tmpstr = gnutls_malloc(len);
if (tmpstr == NULL) {
gnutls_assert();
return GNUTLS_E_MEMORY_ERROR;
}
result = asn1_read_value(node, value, tmpstr, &len);
if (result != ASN1_SUCCESS) {
gnutls_assert();
gnutls_free(tmpstr);
return _gnutls_asn2err(result);
}
if (len == 1)
*ret = tmpstr[0];
else if (len == 2)
*ret = _gnutls_read_uint16(tmpstr);
else if (len == 3)
*ret = _gnutls_read_uint24(tmpstr);
else if (len == 4)
*ret = _gnutls_read_uint32(tmpstr);
else {
gnutls_assert();
gnutls_free(tmpstr);
return GNUTLS_E_INTERNAL_ERROR;
}
gnutls_free(tmpstr);
return 0;
}
/* Writes the specified integer into the specified node.
*/
int
_gnutls_x509_write_uint32(ASN1_TYPE node, const char *value, uint32_t num)
{
uint8_t tmpstr[5];
int result;
tmpstr[0] = 0;
_gnutls_write_uint32(num, tmpstr+1);
if (tmpstr[1] > SCHAR_MAX) {
result = asn1_write_value(node, value, tmpstr, 5);
} else {
result = asn1_write_value(node, value, tmpstr+1, 4);
}
if (result != ASN1_SUCCESS) {
gnutls_assert();
return _gnutls_asn2err(result);
}
return 0;
}