#include "ssl_locl.h"
#include <openssl/ct.h>
+static const SIGALG_LOOKUP *find_sig_alg(SSL *s, X509 *x, EVP_PKEY *pkey);
+
SSL3_ENC_METHOD const TLSv1_enc_data = {
tls1_enc,
tls1_mac,
static int tls1_check_sig_alg(SSL *s, X509 *x, int default_nid)
{
- int sig_nid;
+ int sig_nid, use_pc_sigalgs = 0;
size_t i;
+ const SIGALG_LOOKUP *sigalg;
+ size_t sigalgslen;
if (default_nid == -1)
return 1;
sig_nid = X509_get_signature_nid(x);
if (default_nid)
return sig_nid == default_nid ? 1 : 0;
- for (i = 0; i < s->shared_sigalgslen; i++)
- if (sig_nid == s->shared_sigalgs[i]->sigandhash)
+
+ if (SSL_IS_TLS13(s) && s->s3->tmp.peer_cert_sigalgs != NULL) {
+ /*
+ * If we're in TLSv1.3 then we only get here if we're checking the
+ * chain. If the peer has specified peer_cert_sigalgs then we use them
+ * otherwise we default to normal sigalgs.
+ */
+ sigalgslen = s->s3->tmp.peer_cert_sigalgslen;
+ use_pc_sigalgs = 1;
+ } else {
+ sigalgslen = s->shared_sigalgslen;
+ }
+ for (i = 0; i < sigalgslen; i++) {
+ sigalg = use_pc_sigalgs
+ ? tls1_lookup_sigalg(s->s3->tmp.peer_cert_sigalgs[i])
+ : s->shared_sigalgs[i];
+ if (sig_nid == sigalg->sigandhash)
return 1;
+ }
return 0;
}
}
}
/* Check signature algorithm of each cert in chain */
- if (!tls1_check_sig_alg(s, x, default_nid)) {
+ if (SSL_IS_TLS13(s)) {
+ /*
+ * We only get here if the application has called SSL_check_chain(),
+ * so check_flags is always set.
+ */
+ if (find_sig_alg(s, x, pk) != NULL)
+ rv |= CERT_PKEY_EE_SIGNATURE;
+ } else if (!tls1_check_sig_alg(s, x, default_nid)) {
if (!check_flags)
goto end;
} else
}
/*
- * Returns true if |s| has a usable certificate configured for use
- * with signature scheme |sig|.
- * "Usable" includes a check for presence as well as applying
- * the signature_algorithm_cert restrictions sent by the peer (if any).
- * Returns false if no usable certificate is found.
+ * Checks the given cert against signature_algorithm_cert restrictions sent by
+ * the peer (if any) as well as whether the hash from the sigalg is usable with
+ * the key.
+ * Returns true if the cert is usable and false otherwise.
*/
-static int has_usable_cert(SSL *s, const SIGALG_LOOKUP *sig, int idx)
+static int check_cert_usable(SSL *s, const SIGALG_LOOKUP *sig, X509 *x,
+ EVP_PKEY *pkey)
{
const SIGALG_LOOKUP *lu;
int mdnid, pknid, default_mdnid;
int mandatory_md = 0;
size_t i;
- /* TLS 1.2 callers can override lu->sig_idx, but not TLS 1.3 callers. */
- if (idx == -1)
- idx = sig->sig_idx;
- if (!ssl_has_cert(s, idx))
- return 0;
/* If the EVP_PKEY reports a mandatory digest, allow nothing else. */
ERR_set_mark();
- switch (EVP_PKEY_get_default_digest_nid(s->cert->pkeys[idx].privatekey,
- &default_mdnid)) {
+ switch (EVP_PKEY_get_default_digest_nid(pkey, &default_mdnid)) {
case 2:
mandatory_md = 1;
break;
case 1:
- break;
default: /* If it didn't report a mandatory NID, for whatever reasons,
* just clear the error and allow all hashes to be used. */
- ERR_pop_to_mark();
+ break;
}
+ ERR_pop_to_mark();
if (s->s3->tmp.peer_cert_sigalgs != NULL) {
for (i = 0; i < s->s3->tmp.peer_cert_sigalgslen; i++) {
lu = tls1_lookup_sigalg(s->s3->tmp.peer_cert_sigalgs[i]);
if (lu == NULL
- || !X509_get_signature_info(s->cert->pkeys[idx].x509, &mdnid,
- &pknid, NULL, NULL)
+ || !X509_get_signature_info(x, &mdnid, &pknid, NULL, NULL)
|| (mandatory_md && mdnid != default_mdnid))
continue;
/*
return !mandatory_md || sig->hash == default_mdnid;
}
+/*
+ * Returns true if |s| has a usable certificate configured for use
+ * with signature scheme |sig|.
+ * "Usable" includes a check for presence as well as applying
+ * the signature_algorithm_cert restrictions sent by the peer (if any).
+ * Returns false if no usable certificate is found.
+ */
+static int has_usable_cert(SSL *s, const SIGALG_LOOKUP *sig, int idx)
+{
+ /* TLS 1.2 callers can override sig->sig_idx, but not TLS 1.3 callers. */
+ if (idx == -1)
+ idx = sig->sig_idx;
+ if (!ssl_has_cert(s, idx))
+ return 0;
+
+ return check_cert_usable(s, sig, s->cert->pkeys[idx].x509,
+ s->cert->pkeys[idx].privatekey);
+}
+
+/*
+ * Returns true if the supplied cert |x| and key |pkey| is usable with the
+ * specified signature scheme |sig|, or false otherwise.
+ */
+static int is_cert_usable(SSL *s, const SIGALG_LOOKUP *sig, X509 *x,
+ EVP_PKEY *pkey)
+{
+ size_t idx;
+
+ if (ssl_cert_lookup_by_pkey(pkey, &idx) == NULL)
+ return 0;
+
+ /* Check the key is consistent with the sig alg */
+ if ((int)idx != sig->sig_idx)
+ return 0;
+
+ return check_cert_usable(s, sig, x, pkey);
+}
+
+/*
+ * Find a signature scheme that works with the supplied certificate |x| and key
+ * |pkey|. |x| and |pkey| may be NULL in which case we additionally look at our
+ * available certs/keys to find one that works.
+ */
+static const SIGALG_LOOKUP *find_sig_alg(SSL *s, X509 *x, EVP_PKEY *pkey)
+{
+ const SIGALG_LOOKUP *lu = NULL;
+ size_t i;
+#ifndef OPENSSL_NO_EC
+ int curve = -1;
+#endif
+ EVP_PKEY *tmppkey;
+
+ /* Look for a shared sigalgs matching possible certificates */
+ for (i = 0; i < s->shared_sigalgslen; i++) {
+ lu = s->shared_sigalgs[i];
+
+ /* Skip SHA1, SHA224, DSA and RSA if not PSS */
+ if (lu->hash == NID_sha1
+ || lu->hash == NID_sha224
+ || lu->sig == EVP_PKEY_DSA
+ || lu->sig == EVP_PKEY_RSA)
+ continue;
+ /* Check that we have a cert, and signature_algorithms_cert */
+ if (!tls1_lookup_md(lu, NULL))
+ continue;
+ if ((pkey == NULL && !has_usable_cert(s, lu, -1))
+ || (pkey != NULL && !is_cert_usable(s, lu, x, pkey)))
+ continue;
+
+ tmppkey = (pkey != NULL) ? pkey
+ : s->cert->pkeys[lu->sig_idx].privatekey;
+
+ if (lu->sig == EVP_PKEY_EC) {
+#ifndef OPENSSL_NO_EC
+ if (curve == -1) {
+ EC_KEY *ec = EVP_PKEY_get0_EC_KEY(tmppkey);
+ curve = EC_GROUP_get_curve_name(EC_KEY_get0_group(ec));
+ }
+ if (lu->curve != NID_undef && curve != lu->curve)
+ continue;
+#else
+ continue;
+#endif
+ } else if (lu->sig == EVP_PKEY_RSA_PSS) {
+ /* validate that key is large enough for the signature algorithm */
+ if (!rsa_pss_check_min_key_size(EVP_PKEY_get0(tmppkey), lu))
+ continue;
+ }
+ break;
+ }
+
+ if (i == s->shared_sigalgslen)
+ return NULL;
+
+ return lu;
+}
+
/*
* Choose an appropriate signature algorithm based on available certificates
* Sets chosen certificate and signature algorithm.
s->s3->tmp.sigalg = NULL;
if (SSL_IS_TLS13(s)) {
- size_t i;
-#ifndef OPENSSL_NO_EC
- int curve = -1;
-#endif
-
- /* Look for a certificate matching shared sigalgs */
- for (i = 0; i < s->shared_sigalgslen; i++) {
- lu = s->shared_sigalgs[i];
- sig_idx = -1;
-
- /* Skip SHA1, SHA224, DSA and RSA if not PSS */
- if (lu->hash == NID_sha1
- || lu->hash == NID_sha224
- || lu->sig == EVP_PKEY_DSA
- || lu->sig == EVP_PKEY_RSA)
- continue;
- /* Check that we have a cert, and signature_algorithms_cert */
- if (!tls1_lookup_md(lu, NULL) || !has_usable_cert(s, lu, -1))
- continue;
- if (lu->sig == EVP_PKEY_EC) {
-#ifndef OPENSSL_NO_EC
- if (curve == -1) {
- EC_KEY *ec = EVP_PKEY_get0_EC_KEY(s->cert->pkeys[SSL_PKEY_ECC].privatekey);
-
- curve = EC_GROUP_get_curve_name(EC_KEY_get0_group(ec));
- }
- if (lu->curve != NID_undef && curve != lu->curve)
- continue;
-#else
- continue;
-#endif
- } else if (lu->sig == EVP_PKEY_RSA_PSS) {
- /* validate that key is large enough for the signature algorithm */
- EVP_PKEY *pkey;
-
- pkey = s->cert->pkeys[lu->sig_idx].privatekey;
- if (!rsa_pss_check_min_key_size(EVP_PKEY_get0(pkey), lu))
- continue;
- }
- break;
- }
- if (i == s->shared_sigalgslen) {
+ lu = find_sig_alg(s, NULL, NULL);
+ if (lu == NULL) {
if (!fatalerrs)
return 1;
SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_CHOOSE_SIGALG,