Test the new PSK behaviour

Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5554)

test/sslapitest.c

@@ -1415,6 +1415,8 @@ static const char *srvid;
 
 static int use_session_cb_cnt = 0;
 static int find_session_cb_cnt = 0;
+static int psk_client_cb_cnt = 0;
+static int psk_server_cb_cnt = 0;
 
 static int use_session_cb(SSL *ssl, const EVP_MD *md, const unsigned char **id,
                           size_t *idlen, SSL_SESSION **sess)
@@ -1447,6 +1449,34 @@ static int use_session_cb(SSL *ssl, const EVP_MD *md, const unsigned char **id,
     return 1;
 }
 
+static unsigned int psk_client_cb(SSL *ssl, const char *hint, char *id,
+                                  unsigned int max_id_len,
+                                  unsigned char *psk,
+                                  unsigned int max_psk_len)
+{
+    unsigned int psklen = 0;
+
+    psk_client_cb_cnt++;
+
+    if (strlen(pskid) + 1 > max_id_len)
+        return 0;
+
+    /* We should only ever be called a maximum of twice per connection */
+    if (psk_client_cb_cnt > 2)
+        return 0;
+
+    if (clientpsk == NULL)
+        return 0;
+
+    /* We'll reuse the PSK we set up for TLSv1.3 */
+    if (SSL_SESSION_get_master_key(clientpsk, NULL, 0) > max_psk_len)
+        return 0;
+    psklen = SSL_SESSION_get_master_key(clientpsk, psk, max_psk_len);
+    strncpy(id, pskid, max_id_len);
+
+    return psklen;
+}
+
 static int find_session_cb(SSL *ssl, const unsigned char *identity,
                            size_t identity_len, SSL_SESSION **sess)
 {
@@ -1473,6 +1503,33 @@ static int find_session_cb(SSL *ssl, const unsigned char *identity,
     return 1;
 }
 
+static unsigned int psk_server_cb(SSL *ssl, const char *identity,
+                                  unsigned char *psk, unsigned int max_psk_len)
+{
+    unsigned int psklen = 0;
+
+    psk_server_cb_cnt++;
+
+    /* We should only ever be called a maximum of twice per connection */
+    if (find_session_cb_cnt > 2)
+        return 0;
+
+    if (serverpsk == NULL)
+        return 0;
+
+    /* Identity should match that set by the client */
+    if (strcmp(srvid, identity) != 0) {
+        return 0;
+    }
+
+    /* We'll reuse the PSK we set up for TLSv1.3 */
+    if (SSL_SESSION_get_master_key(serverpsk, NULL, 0) > max_psk_len)
+        return 0;
+    psklen = SSL_SESSION_get_master_key(serverpsk, psk, max_psk_len);
+
+    return psklen;
+}
+
 #define MSG1    "Hello"
 #define MSG2    "World."
 #define MSG3    "This"
@@ -1482,6 +1539,7 @@ static int find_session_cb(SSL *ssl, const unsigned char *identity,
 #define MSG7    "message."
 
 #define TLS13_AES_256_GCM_SHA384_BYTES  ((const unsigned char *)"\x13\x02")
+#define TLS13_AES_128_GCM_SHA256_BYTES  ((const unsigned char *)"\x13\x01")
 
 /*
  * Helper method to setup objects for early data test. Caller frees objects on
@@ -2440,7 +2498,7 @@ static int test_ciphersuite_change(void)
     return testresult;
 }
 
-static int test_tls13_psk(void)
+static int test_tls13_psk(int idx)
 {
     SSL_CTX *sctx = NULL, *cctx = NULL;
     SSL *serverssl = NULL, *clientssl = NULL;
@@ -2458,11 +2516,31 @@ static int test_tls13_psk(void)
                                        &cctx, cert, privkey)))
         goto end;
 
-    SSL_CTX_set_psk_use_session_callback(cctx, use_session_cb);
-    SSL_CTX_set_psk_find_session_callback(sctx, find_session_cb);
+    /*
+     * We use a ciphersuite with SHA256 to ease testing old style PSK callbacks
+     * which will always default to SHA256
+     */
+    if (!TEST_true(SSL_CTX_set_cipher_list(cctx, "TLS13-AES-128-GCM-SHA256")))
+        goto end;
+
+    /*
+     * Test 0: New style callbacks only
+     * Test 1: New and old style callbacks (only the new ones should be used)
+     * Test 2: Old style callbacks only
+     */
+    if (idx == 0 || idx == 1) {
+        SSL_CTX_set_psk_use_session_callback(cctx, use_session_cb);
+        SSL_CTX_set_psk_find_session_callback(sctx, find_session_cb);
+    }
+    if (idx == 1 || idx == 2) {
+        SSL_CTX_set_psk_client_callback(cctx, psk_client_cb);
+        SSL_CTX_set_psk_server_callback(sctx, psk_server_cb);
+    }
     srvid = pskid;
     use_session_cb_cnt = 0;
     find_session_cb_cnt = 0;
+    psk_client_cb_cnt = 0;
+    psk_server_cb_cnt = 0;
 
     /* Check we can create a connection if callback decides not to send a PSK */
     if (!TEST_true(create_ssl_objects(sctx, cctx, &serverssl, &clientssl,
@@ -2470,21 +2548,37 @@ static int test_tls13_psk(void)
             || !TEST_true(create_ssl_connection(serverssl, clientssl,
                                                 SSL_ERROR_NONE))
             || !TEST_false(SSL_session_reused(clientssl))
-            || !TEST_false(SSL_session_reused(serverssl))
-            || !TEST_true(use_session_cb_cnt == 1)
-            || !TEST_true(find_session_cb_cnt == 0))
+            || !TEST_false(SSL_session_reused(serverssl)))
         goto end;
 
+    if (idx == 0 || idx == 1) {
+        if (!TEST_true(use_session_cb_cnt == 1)
+                || !TEST_true(find_session_cb_cnt == 0)
+                   /*
+                    * If no old style callback then below should be 0
+                    * otherwise 1
+                    */
+                || !TEST_true(psk_client_cb_cnt == idx)
+                || !TEST_true(psk_server_cb_cnt == 0))
+            goto end;
+    } else {
+        if (!TEST_true(use_session_cb_cnt == 0)
+                || !TEST_true(find_session_cb_cnt == 0)
+                || !TEST_true(psk_client_cb_cnt == 1)
+                || !TEST_true(psk_server_cb_cnt == 0))
+            goto end;
+    }
+
     shutdown_ssl_connection(serverssl, clientssl);
     serverssl = clientssl = NULL;
-    use_session_cb_cnt = 0;
+    use_session_cb_cnt = psk_client_cb_cnt = 0;
 
     if (!TEST_true(create_ssl_objects(sctx, cctx, &serverssl, &clientssl,
                                              NULL, NULL)))
         goto end;
 
     /* Create the PSK */
-    cipher = SSL_CIPHER_find(clientssl, TLS13_AES_256_GCM_SHA384_BYTES);
+    cipher = SSL_CIPHER_find(clientssl, TLS13_AES_128_GCM_SHA256_BYTES);
     clientpsk = SSL_SESSION_new();
     if (!TEST_ptr(clientpsk)
             || !TEST_ptr(cipher)
@@ -2500,14 +2594,27 @@ static int test_tls13_psk(void)
     /* Check we can create a connection and the PSK is used */
     if (!TEST_true(create_ssl_connection(serverssl, clientssl, SSL_ERROR_NONE))
             || !TEST_true(SSL_session_reused(clientssl))
-            || !TEST_true(SSL_session_reused(serverssl))
-            || !TEST_true(use_session_cb_cnt == 1)
-            || !TEST_true(find_session_cb_cnt == 1))
+            || !TEST_true(SSL_session_reused(serverssl)))
         goto end;
 
+    if (idx == 0 || idx == 1) {
+        if (!TEST_true(use_session_cb_cnt == 1)
+                || !TEST_true(find_session_cb_cnt == 1)
+                || !TEST_true(psk_client_cb_cnt == 0)
+                || !TEST_true(psk_server_cb_cnt == 0))
+            goto end;
+    } else {
+        if (!TEST_true(use_session_cb_cnt == 0)
+                || !TEST_true(find_session_cb_cnt == 0)
+                || !TEST_true(psk_client_cb_cnt == 1)
+                || !TEST_true(psk_server_cb_cnt == 1))
+            goto end;
+    }
+
     shutdown_ssl_connection(serverssl, clientssl);
     serverssl = clientssl = NULL;
     use_session_cb_cnt = find_session_cb_cnt = 0;
+    psk_client_cb_cnt = psk_server_cb_cnt = 0;
 
     if (!TEST_true(create_ssl_objects(sctx, cctx, &serverssl, &clientssl,
                                              NULL, NULL)))
@@ -2523,14 +2630,27 @@ static int test_tls13_psk(void)
      */
     if (!TEST_true(create_ssl_connection(serverssl, clientssl, SSL_ERROR_NONE))
             || !TEST_true(SSL_session_reused(clientssl))
-            || !TEST_true(SSL_session_reused(serverssl))
-            || !TEST_true(use_session_cb_cnt == 2)
-            || !TEST_true(find_session_cb_cnt == 2))
+            || !TEST_true(SSL_session_reused(serverssl)))
         goto end;
 
+    if (idx == 0 || idx == 1) {
+        if (!TEST_true(use_session_cb_cnt == 2)
+                || !TEST_true(find_session_cb_cnt == 2)
+                || !TEST_true(psk_client_cb_cnt == 0)
+                || !TEST_true(psk_server_cb_cnt == 0))
+            goto end;
+    } else {
+        if (!TEST_true(use_session_cb_cnt == 0)
+                || !TEST_true(find_session_cb_cnt == 0)
+                || !TEST_true(psk_client_cb_cnt == 2)
+                || !TEST_true(psk_server_cb_cnt == 2))
+            goto end;
+    }
+
     shutdown_ssl_connection(serverssl, clientssl);
     serverssl = clientssl = NULL;
     use_session_cb_cnt = find_session_cb_cnt = 0;
+    psk_client_cb_cnt = psk_server_cb_cnt = 0;
 
     /*
      * Check that if the server rejects the PSK we can still connect, but with
@@ -2542,11 +2662,27 @@ static int test_tls13_psk(void)
             || !TEST_true(create_ssl_connection(serverssl, clientssl,
                                                 SSL_ERROR_NONE))
             || !TEST_false(SSL_session_reused(clientssl))
-            || !TEST_false(SSL_session_reused(serverssl))
-            || !TEST_true(use_session_cb_cnt == 1)
-            || !TEST_true(find_session_cb_cnt == 1))
+            || !TEST_false(SSL_session_reused(serverssl)))
         goto end;
 
+    if (idx == 0 || idx == 1) {
+        if (!TEST_true(use_session_cb_cnt == 1)
+                || !TEST_true(find_session_cb_cnt == 1)
+                || !TEST_true(psk_client_cb_cnt == 0)
+                   /*
+                    * If no old style callback then below should be 0
+                    * otherwise 1
+                    */
+                || !TEST_true(psk_server_cb_cnt == idx))
+            goto end;
+    } else {
+        if (!TEST_true(use_session_cb_cnt == 0)
+                || !TEST_true(find_session_cb_cnt == 0)
+                || !TEST_true(psk_client_cb_cnt == 1)
+                || !TEST_true(psk_server_cb_cnt == 1))
+            goto end;
+    }
+
     shutdown_ssl_connection(serverssl, clientssl);
     serverssl = clientssl = NULL;
     testresult = 1;
@@ -3506,7 +3642,7 @@ int setup_tests(void)
 #endif
 #ifndef OPENSSL_NO_TLS1_3
     ADD_TEST(test_ciphersuite_change);
-    ADD_TEST(test_tls13_psk);
+    ADD_ALL_TESTS(test_tls13_psk, 3);
     ADD_ALL_TESTS(test_custom_exts, 5);
     ADD_TEST(test_stateless);
     ADD_TEST(test_pha_key_update);