Check that the default signature type is allowed

TLS < 1.2 has fixed signature algorithms: MD5+SHA1 for RSA and SHA1 for the
others. TLS 1.2 sends a list of supported ciphers, but allows not sending
it in which case SHA1 is used. TLS 1.3 makes sending the list mandatory.

When we didn't receive a list from the client, we always used the
defaults without checking that they are allowed by the configuration.

Reviewed-by: Paul Dale <paul.dale@oracle.com>
GH: #10784

diff --git a/ssl/ssl_local.h b/ssl/ssl_local.h
index 14515cadfe336a4a07395df46e22418e91f48047..43b0623a0b9d567b8a7543acacae67c935937fe1 100644 (file)
--- a/ssl/ssl_local.h
+++ b/ssl/ssl_local.h
@@ -2606,7 +2606,7 @@ __owur int tls_check_sigalg_curve(const SSL *s, int curve);
 #  endif
 __owur int tls12_check_peer_sigalg(SSL *s, uint16_t, EVP_PKEY *pkey);
 __owur int ssl_set_client_disabled(SSL *s);
-__owur int ssl_cipher_disabled(SSL *s, const SSL_CIPHER *c, int op, int echde);
+__owur int ssl_cipher_disabled(const SSL *s, const SSL_CIPHER *c, int op, int echde);
 
 __owur int ssl_handshake_hash(SSL *s, unsigned char *out, size_t outlen,
                                  size_t *hashlen);

diff --git a/ssl/t1_lib.c b/ssl/t1_lib.c
index afb72857e548368f05d619b5b580ae021594e1fe..0504f6bba1dde341d9bc26c0ea2a102cc18c46ed 100644 (file)
--- a/ssl/t1_lib.c
+++ b/ssl/t1_lib.c
@@ -22,6 +22,7 @@
 #include <openssl/ct.h>
 
 static const SIGALG_LOOKUP *find_sig_alg(SSL *s, X509 *x, EVP_PKEY *pkey);
+static int tls12_sigalg_allowed(const SSL *s, int op, const SIGALG_LOOKUP *lu);
 
 SSL3_ENC_METHOD const TLSv1_enc_data = {
     tls1_enc,
@@ -928,8 +929,11 @@ static int rsa_pss_check_min_key_size(const RSA *rsa, const SIGALG_LOOKUP *lu)
 }
 
 /*
- * Return a signature algorithm for TLS < 1.2 where the signature type
- * is fixed by the certificate type.
+ * Returns a signature algorithm when the peer did not send a list of supported
+ * signature algorithms. The signature algorithm is fixed for the certificate
+ * type. |idx| is a certificate type index (SSL_PKEY_*). When |idx| is -1 the
+ * certificate type from |s| will be used.
+ * Returns the signature algorithm to use, or NULL on error.
  */
 static const SIGALG_LOOKUP *tls1_get_legacy_sigalg(const SSL *s, int idx)
 {
@@ -972,8 +976,12 @@ static const SIGALG_LOOKUP *tls1_get_legacy_sigalg(const SSL *s, int idx)
 
         if (!tls1_lookup_md(lu, NULL))
             return NULL;
+        if (!tls12_sigalg_allowed(s, SSL_SECOP_SIGALG_SUPPORTED, lu))
+            return NULL;
         return lu;
     }
+    if (!tls12_sigalg_allowed(s, SSL_SECOP_SIGALG_SUPPORTED, &legacy_rsa_sigalg))
+        return NULL;
     return &legacy_rsa_sigalg;
 }
 /* Set peer sigalg based key type */
@@ -1255,7 +1263,7 @@ int ssl_set_client_disabled(SSL *s)
  *
  * Returns 1 when it's disabled, 0 when enabled.
  */
-int ssl_cipher_disabled(SSL *s, const SSL_CIPHER *c, int op, int ecdhe)
+int ssl_cipher_disabled(const SSL *s, const SSL_CIPHER *c, int op, int ecdhe)
 {
     if (c->algorithm_mkey & s->s3.tmp.mask_k
         || c->algorithm_auth & s->s3.tmp.mask_a)
@@ -1635,7 +1643,7 @@ SSL_TICKET_STATUS tls_decrypt_ticket(SSL *s, const unsigned char *etick,
 }
 
 /* Check to see if a signature algorithm is allowed */
-static int tls12_sigalg_allowed(SSL *s, int op, const SIGALG_LOOKUP *lu)
+static int tls12_sigalg_allowed(const SSL *s, int op, const SIGALG_LOOKUP *lu)
 {
     unsigned char sigalgstr[2];
     int secbits;

diff --git a/test/recipes/70-test_sslsigalgs.t b/test/recipes/70-test_sslsigalgs.t
index 43cad5f4d771d3cd38deacebcc118f186c35360b..98482079b32cd3a69bfc580795acd34bd30ff7f0 100644 (file)
--- a/test/recipes/70-test_sslsigalgs.t
+++ b/test/recipes/70-test_sslsigalgs.t
@@ -53,7 +53,7 @@ use constant {
 
 #Test 1: Default sig algs should succeed
 $proxy->start() or plan skip_all => "Unable to start up Proxy for tests";
-plan tests => 22;
+plan tests => 24;
 ok(TLSProxy::Message->success, "Default sigalgs");
 my $testtype;
 
@@ -132,19 +132,40 @@ SKIP: {
 }
 
 SKIP: {
-    skip "EC or TLSv1.2 disabled", 8 if disabled("tls1_2") || disabled("ec");
+    skip "EC or TLSv1.2 disabled", 10 if disabled("tls1_2") || disabled("ec");
 
     $proxy->filter(\&sigalgs_filter);
 
-    #Test 10: Sending no sig algs extension in TLSv1.2 should succeed
+    #Test 10: Sending no sig algs extension in TLSv1.2 should succeed at
+    #         security level 1
     $proxy->clear();
     $testtype = NO_SIG_ALGS_EXT;
-    $proxy->clientflags("-no_tls1_3");
-    $proxy->ciphers("ECDHE-RSA-AES128-SHA");
+    $proxy->clientflags("-no_tls1_3 -cipher DEFAULT\@SECLEVEL=1");
+    $proxy->ciphers("ECDHE-RSA-AES128-SHA\@SECLEVEL=1");
+    $proxy->start();
+    ok(TLSProxy::Message->success, "No TLSv1.2 sigalgs seclevel 1");
+
+    #Test 11: Sending no sig algs extension in TLSv1.2 should fail at security
+    #         level 2 since it will try to use SHA1. Testing client at level 1,
+    #         server level 2.
+    $proxy->clear();
+    $testtype = NO_SIG_ALGS_EXT;
+    $proxy->clientflags("-tls1_2 -cipher DEFAULT\@SECLEVEL=1");
+    $proxy->ciphers("DEFAULT\@SECLEVEL=2");
+    $proxy->start();
+    ok(TLSProxy::Message->fail, "No TLSv1.2 sigalgs server seclevel 2");
+
+    #Test 12: Sending no sig algs extension in TLSv1.2 should fail at security
+    #         level 2 since it will try to use SHA1. Testing client at level 2,
+    #         server level 1.
+    $proxy->clear();
+    $testtype = NO_SIG_ALGS_EXT;
+    $proxy->clientflags("-tls1_2 -cipher DEFAULT\@SECLEVEL=2");
+    $proxy->ciphers("DEFAULT\@SECLEVEL=1");
     $proxy->start();
-    ok(TLSProxy::Message->success, "No TLSv1.2 sigalgs");
+    ok(TLSProxy::Message->fail, "No TLSv1.2 sigalgs client seclevel 2");
 
-    #Test 11: Sending an empty sig algs extension in TLSv1.2 should fail
+    #Test 13: Sending an empty sig algs extension in TLSv1.2 should fail
     $proxy->clear();
     $testtype = EMPTY_SIG_ALGS_EXT;
     $proxy->clientflags("-no_tls1_3");
@@ -152,7 +173,7 @@ SKIP: {
     $proxy->start();
     ok(TLSProxy::Message->fail, "Empty TLSv1.2 sigalgs");
 
-    #Test 12: Sending a list with no recognised sig algs in TLSv1.2 should fail
+    #Test 14: Sending a list with no recognised sig algs in TLSv1.2 should fail
     $proxy->clear();
     $testtype = NO_KNOWN_SIG_ALGS;
     $proxy->clientflags("-no_tls1_3");
@@ -160,7 +181,7 @@ SKIP: {
     $proxy->start();
     ok(TLSProxy::Message->fail, "No known TLSv1.3 sigalgs");
 
-    #Test 13: Sending a sig algs list without pss for an RSA cert in TLSv1.2
+    #Test 15: Sending a sig algs list without pss for an RSA cert in TLSv1.2
     #         should succeed
     $proxy->clear();
     $testtype = NO_PSS_SIG_ALGS;
@@ -169,7 +190,7 @@ SKIP: {
     $proxy->start();
     ok(TLSProxy::Message->success, "No PSS TLSv1.2 sigalgs");
 
-    #Test 14: Sending only TLSv1.3 PSS sig algs in TLSv1.2 should succeed
+    #Test 16: Sending only TLSv1.3 PSS sig algs in TLSv1.2 should succeed
     $proxy->clear();
     $testtype = PSS_ONLY_SIG_ALGS;
     $proxy->serverflags("-no_tls1_3");
@@ -177,7 +198,7 @@ SKIP: {
     $proxy->start();
     ok(TLSProxy::Message->success, "PSS only sigalgs in TLSv1.2");
 
-    #Test 15: Responding with a sig alg we did not send in TLSv1.2 should fail
+    #Test 17: Responding with a sig alg we did not send in TLSv1.2 should fail
     #         We send rsa_pkcs1_sha256 and respond with rsa_pss_rsae_sha256
     #         TODO(TLS1.3): Add a similar test to the TLSv1.3 section above
     #         when we have an API capable of configuring the TLSv1.3 sig algs
@@ -188,7 +209,7 @@ SKIP: {
     $proxy->start();
     ok(TLSProxy::Message->fail, "Sigalg we did not send in TLSv1.2");
 
-    #Test 16: Sending a valid sig algs list but not including a sig type that
+    #Test 18: Sending a valid sig algs list but not including a sig type that
     #         matches the certificate should fail in TLSv1.2
     $proxy->clear();
     $proxy->clientflags("-no_tls1_3 -sigalgs ECDSA+SHA256");
@@ -198,7 +219,7 @@ SKIP: {
     ok(TLSProxy::Message->fail, "No matching TLSv1.2 sigalgs");
     $proxy->filter(\&sigalgs_filter);
 
-    #Test 17: No sig algs extension, ECDSA cert, TLSv1.2 should succeed
+    #Test 19: No sig algs extension, ECDSA cert, TLSv1.2 should succeed
     $proxy->clear();
     $testtype = NO_SIG_ALGS_EXT;
     $proxy->clientflags("-no_tls1_3");
@@ -214,7 +235,7 @@ SKIP: {
 my ($dsa_status, $sha1_status, $sha224_status);
 SKIP: {
     skip "TLSv1.3 disabled", 2 if disabled("tls1_3") || disabled("dsa");
-    #Test 18: signature_algorithms with 1.3-only ClientHello
+    #Test 20: signature_algorithms with 1.3-only ClientHello
     $testtype = PURE_SIGALGS;
     $dsa_status = $sha1_status = $sha224_status = 0;
     $proxy->clear();
@@ -224,7 +245,7 @@ SKIP: {
     ok($dsa_status && $sha1_status && $sha224_status,
        "DSA/SHA2 sigalg sent for 1.3-only ClientHello");
 
-    #Test 19: signature_algorithms with backwards compatible ClientHello
+    #Test 21: signature_algorithms with backwards compatible ClientHello
     SKIP: {
         skip "TLSv1.2 disabled", 1 if disabled("tls1_2");
         $testtype = COMPAT_SIGALGS;
@@ -239,21 +260,21 @@ SKIP: {
 
 SKIP: {
     skip "TLSv1.3 disabled", 3 if disabled("tls1_3");
-    #Test 20: Insert signature_algorithms_cert that match normal sigalgs
+    #Test 22: Insert signature_algorithms_cert that match normal sigalgs
     $testtype = SIGALGS_CERT_ALL;
     $proxy->clear();
     $proxy->filter(\&modify_sigalgs_cert_filter);
     $proxy->start();
     ok(TLSProxy::Message->success, "sigalgs_cert in TLSv1.3");
 
-    #Test 21: Insert signature_algorithms_cert that forces PKCS#1 cert
+    #Test 23: Insert signature_algorithms_cert that forces PKCS#1 cert
     $testtype = SIGALGS_CERT_PKCS;
     $proxy->clear();
     $proxy->filter(\&modify_sigalgs_cert_filter);
     $proxy->start();
     ok(TLSProxy::Message->success, "sigalgs_cert in TLSv1.3 with PKCS#1 cert");
 
-    #Test 22: Insert signature_algorithms_cert that fails
+    #Test 24: Insert signature_algorithms_cert that fails
     $testtype = SIGALGS_CERT_INVALID;
     $proxy->clear();
     $proxy->filter(\&modify_sigalgs_cert_filter);