Cleanup record length checks for KTLS

In some corner cases the check for packets
which exceed the allowed record length was missing
when KTLS is initially enabled, when some
unprocessed packets are still pending.

Add at least some tests for KTLS, since we have
currently not very much test coverage for KTLS.

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/17504)

(cherry picked from commit 8fff986d52606e1a33f9404504535e2e2aee3e8b)

diff --git a/ssl/record/ssl3_record.c b/ssl/record/ssl3_record.c
index d4101618c69d6a29a5dbb8ea4234765fcb5ecbd9..4229c9c392a2c2201e0060250a174aec00e97b36 100644 (file)
--- a/ssl/record/ssl3_record.c
+++ b/ssl/record/ssl3_record.c
@@ -191,7 +191,7 @@ int ssl3_get_record(SSL *s)
 
     rr = RECORD_LAYER_get_rrec(&s->rlayer);
     rbuf = RECORD_LAYER_get_rbuf(&s->rlayer);
-    is_ktls_left = (rbuf->left > 0);
+    is_ktls_left = (SSL3_BUFFER_get_left(rbuf) > 0);
     max_recs = s->max_pipelines;
     if (max_recs == 0)
         max_recs = 1;
@@ -408,7 +408,11 @@ int ssl3_get_record(SSL *s)
                 len -= SSL3_RT_MAX_COMPRESSED_OVERHEAD;
 #endif
 
-            if (thisrr->length > len && !BIO_get_ktls_recv(s->rbio)) {
+            /* KTLS may use all of the buffer */
+            if (BIO_get_ktls_recv(s->rbio) && !is_ktls_left)
+                len = SSL3_BUFFER_get_left(rbuf);
+
+            if (thisrr->length > len) {
                 SSLfatal(s, SSL_AD_RECORD_OVERFLOW,
                          SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
                 return -1;
@@ -711,16 +715,27 @@ int ssl3_get_record(SSL *s)
             goto end;
         }
 
+        /*
+         * Usually thisrr->length is the length of a single record, but when
+         * KTLS handles the decryption, thisrr->length may be larger than
+         * SSL3_RT_MAX_PLAIN_LENGTH because the kernel may have coalesced
+         * multiple records.
+         * Therefore we have to rely on KTLS to check the plaintext length
+         * limit in the kernel.
+         */
         if (thisrr->length > SSL3_RT_MAX_PLAIN_LENGTH
-            && !BIO_get_ktls_recv(s->rbio)) {
+                && (!BIO_get_ktls_recv(s->rbio) || is_ktls_left)) {
             SSLfatal(s, SSL_AD_RECORD_OVERFLOW, SSL_R_DATA_LENGTH_TOO_LONG);
             goto end;
         }
 
-        /* If received packet overflows current Max Fragment Length setting */
+        /*
+         * Check if the received packet overflows the current
+         * Max Fragment Length setting.
+         * Note: USE_MAX_FRAGMENT_LENGTH_EXT and KTLS are mutually exclusive.
+         */
         if (s->session != NULL && USE_MAX_FRAGMENT_LENGTH_EXT(s->session)
-                && thisrr->length > GET_MAX_FRAGMENT_LENGTH(s->session)
-                && !BIO_get_ktls_recv(s->rbio)) {
+                && thisrr->length > GET_MAX_FRAGMENT_LENGTH(s->session)) {
             SSLfatal(s, SSL_AD_RECORD_OVERFLOW, SSL_R_DATA_LENGTH_TOO_LONG);
             goto end;
         }

diff --git a/test/recipes/80-test_ssl_old.t b/test/recipes/80-test_ssl_old.t
index b144bc9fb9ca6136489b904803ba48af8e70a047..c1fb30f6b225d1531ddcc17c4e303aadebbe748e 100644 (file)
--- a/test/recipes/80-test_ssl_old.t
+++ b/test/recipes/80-test_ssl_old.t
@@ -346,11 +346,9 @@ sub testssl {
     }
 
 
-    # plan tests => 11;
-
     subtest 'standard SSL tests' => sub {
         ######################################################################
-        plan tests => 13;
+        plan tests => 19;
 
       SKIP: {
           skip "SSLv3 is not supported by this OpenSSL build", 4
@@ -378,7 +376,7 @@ sub testssl {
         }
 
       SKIP: {
-          skip "Neither SSLv3 nor any TLS version are supported by this OpenSSL build", 8
+          skip "Neither SSLv3 nor any TLS version are supported by this OpenSSL build", 14
               if $no_anytls;
 
         SKIP: {
@@ -406,17 +404,29 @@ sub testssl {
              'test sslv2/sslv3 with both client and server authentication via BIO pair and app verify');
 
         SKIP: {
-            skip "No IPv4 available on this machine", 1
+            skip "No IPv4 available on this machine", 4
                 unless !disabled("sock") && have_IPv4();
             ok(run(test([@ssltest, "-ipv4"])),
                'test TLS via IPv4');
+            ok(run(test([@ssltest, "-ipv4", "-client_ktls"])),
+               'test TLS via IPv4 + ktls(client)');
+            ok(run(test([@ssltest, "-ipv4", "-server_ktls"])),
+               'test TLS via IPv4 + ktls(server)');
+            ok(run(test([@ssltest, "-ipv4", "-client_ktls", "-server_ktls"])),
+               'test TLS via IPv4 + ktls');
           }
 
         SKIP: {
-            skip "No IPv6 available on this machine", 1
+            skip "No IPv6 available on this machine", 4
                 unless !disabled("sock") && have_IPv6();
             ok(run(test([@ssltest, "-ipv6"])),
                'test TLS via IPv6');
+            ok(run(test([@ssltest, "-ipv6", "-client_ktls"])),
+               'test TLS via IPv6 + ktls(client)');
+            ok(run(test([@ssltest, "-ipv6", "-server_ktls"])),
+               'test TLS via IPv6 + ktls(client)');
+            ok(run(test([@ssltest, "-ipv6", "-client_ktls", "-server_ktls"])),
+               'test TLS via IPv6 + ktls');
           }
         }
     };

diff --git a/test/ssl_old_test.c b/test/ssl_old_test.c
index 6a206d595e3691defda5e69b34875dcc82baee7b..f1e678623c430739fd8ee23d0e553af19739c65a 100644 (file)
--- a/test/ssl_old_test.c
+++ b/test/ssl_old_test.c
@@ -711,6 +711,8 @@ static void sv_usage(void)
     fprintf(stderr, " -client_sess_in <file>     - Read the client session from a file\n");
     fprintf(stderr, " -should_reuse <number>     - The expected state of reusing the session\n");
     fprintf(stderr, " -no_ticket    - do not issue TLS session ticket\n");
+    fprintf(stderr, " -client_ktls  - try to enable client KTLS\n");
+    fprintf(stderr, " -server_ktls  - try to enable server KTLS\n");
     fprintf(stderr, " -provider <name>    - Load the given provider into the library context\n");
     fprintf(stderr, " -config <cnf>    - Load the given config file into the library context\n");
 }
@@ -883,6 +885,7 @@ int main(int argc, char *argv[])
     int number = 1, reuse = 0;
     int should_reuse = -1;
     int no_ticket = 0;
+    int client_ktls = 0, server_ktls = 0;
     long bytes = 256L;
 #ifndef OPENSSL_NO_DH
     EVP_PKEY *dhpkey;
@@ -1167,6 +1170,10 @@ int main(int argc, char *argv[])
             should_reuse = !!atoi(*(++argv));
         } else if (strcmp(*argv, "-no_ticket") == 0) {
             no_ticket = 1;
+        } else if (strcmp(*argv, "-client_ktls") == 0) {
+            client_ktls = 1;
+        } else if (strcmp(*argv, "-server_ktls") == 0) {
+            server_ktls = 1;
         } else if (strcmp(*argv, "-provider") == 0) {
             if (--argc < 1)
                 goto bad;
@@ -1724,6 +1731,10 @@ int main(int argc, char *argv[])
 
     if (sn_client)
         SSL_set_tlsext_host_name(c_ssl, sn_client);
+    if (client_ktls)
+        SSL_set_options(c_ssl, SSL_OP_ENABLE_KTLS);
+    if (server_ktls)
+        SSL_set_options(s_ssl, SSL_OP_ENABLE_KTLS);
 
     if (!set_protocol_version(server_min_proto, s_ssl, SSL_CTRL_SET_MIN_PROTO_VERSION))
         goto end;