Add a bi-directional shutdown test

Reviewed-by: NBernd Edlinger <bernd.edlinger@hotmail.de>
Reviewed-by: NKurt Roeckx <kurt@roeckx.be>
(Merged from https://github.com/openssl/openssl/pull/6340)

test/sslapitest.c

@@ -4972,6 +4972,128 @@ static int test_ticket_callbacks(int tst)
     return testresult;
 }
 
+/*
+ * Test bi-directional shutdown.
+ * Test 0: TLSv1.2
+ * Test 1: TLSv1.2, server continues to read/write after client shutdown
+ * Test 2: TLSv1.3, no pending NewSessionTicket messages
+ * Test 3: TLSv1.3, pending NewSessionTicket messages
+ * Test 4: TLSv1.3, server continues to read/write after client shutdown, client
+ *                  reads it
+ * Test 5: TLSv1.3, server continues to read/write after client shutdown, client
+ *                  doesn't read it
+ */
+static int test_shutdown(int tst)
+{
+    SSL_CTX *cctx = NULL, *sctx = NULL;
+    SSL *clientssl = NULL, *serverssl = NULL;
+    int testresult = 0;
+    char msg[] = "A test message";
+    char buf[80];
+    size_t written, readbytes;
+
+#ifdef OPENSSL_NO_TLS1_2
+    if (tst == 0)
+        return 1;
+#endif
+#ifdef OPENSSL_NO_TLS1_3
+    if (tst != 0)
+        return 1;
+#endif
+
+    if (!TEST_true(create_ssl_ctx_pair(TLS_server_method(),
+                                       TLS_client_method(),
+                                       TLS1_VERSION,
+                                       (tst <= 1) ? TLS1_2_VERSION
+                                                  : TLS1_3_VERSION,
+                                       &sctx, &cctx, cert, privkey))
+            || !TEST_true(create_ssl_objects(sctx, cctx, &serverssl, &clientssl,
+                                             NULL, NULL)))
+        goto end;
+
+    if (tst == 3) {
+        if (!TEST_true(create_bare_ssl_connection(serverssl, clientssl,
+                                                  SSL_ERROR_NONE)))
+            goto end;
+    } else if (!TEST_true(create_ssl_connection(serverssl, clientssl,
+                                              SSL_ERROR_NONE))) {
+        goto end;
+    }
+
+    if (!TEST_int_eq(SSL_shutdown(clientssl), 0))
+        goto end;
+
+    if (tst >= 4) {
+        /*
+         * Reading on the server after the client has sent close_notify should
+         * fail and provide SSL_ERROR_ZERO_RETURN
+         */
+        if (!TEST_false(SSL_read_ex(serverssl, buf, sizeof(buf), &readbytes))
+                || !TEST_int_eq(SSL_get_error(serverssl, 0),
+                                SSL_ERROR_ZERO_RETURN)
+                || !TEST_int_eq(SSL_get_shutdown(serverssl),
+                                SSL_RECEIVED_SHUTDOWN)
+                   /*
+                    * Even though we're shutdown on receive we should still be
+                    * able to write.
+                    */
+                || !TEST_true(SSL_write(serverssl, msg, sizeof(msg)))
+                || !TEST_int_eq(SSL_shutdown(serverssl), 1))
+            goto end;
+        if (tst == 4) {
+                   /* Should still be able to read data from server */
+            if (!TEST_true(SSL_read_ex(clientssl, buf, sizeof(buf),
+                                          &readbytes))
+                    || !TEST_size_t_eq(readbytes, sizeof(msg))
+                    || !TEST_int_eq(memcmp(msg, buf, readbytes), 0))
+                goto end;
+        }
+    }
+
+    /* Writing on the client after sending close_notify shouldn't be possible */
+    if (!TEST_false(SSL_write_ex(clientssl, msg, sizeof(msg), &written))
+               /*
+                * Writing on the server after sending close_notify shouldn't be
+                * possible.
+                */
+            || !TEST_false(SSL_write_ex(clientssl, msg, sizeof(msg), &written)))
+        goto end;
+
+    if (tst < 4) {
+        /*
+         * For these tests the client has sent close_notify but it has not yet
+         * been received by the server. The server has not sent close_notify
+         * yet.
+         */
+        if (!TEST_int_eq(SSL_shutdown(serverssl), 0)
+                || !TEST_int_eq(SSL_shutdown(clientssl), 1)
+                || !TEST_int_eq(SSL_shutdown(serverssl), 1))
+            goto end;
+    } else {
+        /*
+         * In this test the client has sent close_notify and it has been
+         * received by the server which has responded with a close_notify. The
+         * client needs to read the close_notify sent by the server. When
+         * tst == 5, there is application data to be read first but this is
+         * discarded with a -1 return value.
+         */
+        if (tst == 5 && !TEST_int_eq(SSL_shutdown(clientssl), -1))
+            goto end;
+        if (!TEST_int_eq(SSL_shutdown(clientssl), 1))
+            goto end;
+    }
+
+    testresult = 1;
+
+ end:
+    SSL_free(serverssl);
+    SSL_free(clientssl);
+    SSL_CTX_free(sctx);
+    SSL_CTX_free(cctx);
+
+    return testresult;
+}
+
 int setup_tests(void)
 {
     if (!TEST_ptr(cert = test_get_argument(0))
@@ -5069,6 +5191,7 @@ int setup_tests(void)
     ADD_ALL_TESTS(test_ssl_pending, 2);
     ADD_ALL_TESTS(test_ssl_get_shared_ciphers, OSSL_NELEM(shared_ciphers_data));
     ADD_ALL_TESTS(test_ticket_callbacks, 12);
+    ADD_ALL_TESTS(test_shutdown, 6);
     return 1;
 }
 

test/ssltestlib.c

@@ -680,12 +680,14 @@ int create_ssl_objects(SSL_CTX *serverctx, SSL_CTX *clientctx, SSL **sssl,
     return 0;
 }
 
-int create_ssl_connection(SSL *serverssl, SSL *clientssl, int want)
+/*
+ * Create an SSL connection, but does not ready any post-handshake
+ * NewSessionTicket messages.
+ */
+int create_bare_ssl_connection(SSL *serverssl, SSL *clientssl, int want)
 {
-    int retc = -1, rets = -1, err, abortctr = 0, i;
+    int retc = -1, rets = -1, err, abortctr = 0;
     int clienterr = 0, servererr = 0;
-    unsigned char buf;
-    size_t readbytes;
     int isdtls = SSL_is_dtls(serverssl);
 
     do {
@@ -738,6 +740,22 @@ int create_ssl_connection(SSL *serverssl, SSL *clientssl, int want)
         }
     } while (retc <=0 || rets <= 0);
 
+    return 1;
+}
+
+/*
+ * Create an SSL connection including any post handshake NewSessionTicket
+ * messages.
+ */
+int create_ssl_connection(SSL *serverssl, SSL *clientssl, int want)
+{
+    int i;
+    unsigned char buf;
+    size_t readbytes;
+
+    if (!create_bare_ssl_connection(serverssl, clientssl, want))
+        return 0;
+
     /*
      * We attempt to read some data on the client side which we expect to fail.
      * This will ensure we have received the NewSessionTicket in TLSv1.3 where

test/ssltestlib.h

@@ -18,6 +18,7 @@ int create_ssl_ctx_pair(const SSL_METHOD *sm, const SSL_METHOD *cm,
                         char *privkeyfile);
 int create_ssl_objects(SSL_CTX *serverctx, SSL_CTX *clientctx, SSL **sssl,
                        SSL **cssl, BIO *s_to_c_fbio, BIO *c_to_s_fbio);
+int create_bare_ssl_connection(SSL *serverssl, SSL *clientssl, int want);
 int create_ssl_connection(SSL *serverssl, SSL *clientssl, int want);
 void shutdown_ssl_connection(SSL *serverssl, SSL *clientssl);