Add cipher suite selection to test applications.

Signed-off-by: Achim Kraus <[email protected]>

tests/CMakeLists.txt

@@ -23,7 +23,7 @@ cmake_minimum_required(VERSION 3.5)
 
 project(tinydtls-tests)
 
-add_executable(dtls-server dtls-server.c)
+add_executable(dtls-server dtls-server.c dtls_ciphers_util.c)
 target_link_libraries(dtls-server LINK_PUBLIC tinydtls)
 target_compile_options(dtls-server PUBLIC -Wall -DTEST_INCLUDE -DDTLSv12 -DWITH_SHA256)
 if(${WARNING_TO_ERROR})
@@ -37,7 +37,7 @@ if(${WARNING_TO_ERROR})
     target_compile_options(ccm-test PUBLIC -Werror)
 endif()
 
-add_executable(dtls-client dtls-client.c)
+add_executable(dtls-client dtls-client.c dtls_ciphers_util.c)
 target_link_libraries(dtls-client LINK_PUBLIC tinydtls)
 target_compile_options(dtls-client PUBLIC -Wall -DTEST_INCLUDE -DDTLSv12 -DWITH_SHA256)
 if(${WARNING_TO_ERROR})

tests/dtls-client.c

@@ -21,6 +21,7 @@
 
 #include "global.h" 
 #include "dtls_debug.h"
+#include "dtls_ciphers_util.h"
 #include "dtls.h" 
 
 #define DEFAULT_PORT 20220
@@ -214,6 +215,16 @@ send_to_peer(struct dtls_context_t *ctx,
 		&session->addr.sa, session->size);
 }
 
+static const dtls_cipher_t* ciphers = NULL;
+
+static void
+get_cipher_suites(struct dtls_context_t *ctx,
+    session_t *session, const dtls_cipher_t **cipher_suites) {
+  (void) ctx;
+  (void) session;
+  *cipher_suites = ciphers;
+}
+
 static int
 dtls_handle_read(struct dtls_context_t *ctx) {
   int fd;
@@ -308,9 +319,9 @@ usage( const char *program, const char *version) {
   fprintf(stderr, "%s v%s -- DTLS client implementation\n"
 	  "(c) 2011-2014 Olaf Bergmann <[email protected]>\n\n"
 #ifdef DTLS_PSK
-	  "usage: %s [-i file] [-k file] [-o file] [-p port] [-v num] addr [port]\n"
+	  "usage: %s [-i file] [-k file] [-o file] [-p port] [-v num] [-c cipher-suites] addr [port]\n"
 #else /*  DTLS_PSK */
-	  "usage: %s [-o file] [-p port] [-v num] addr [port]\n"
+	  "usage: %s [-o file] [-p port] [-v num] [-c cipher-suites] addr [port]\n"
 #endif /* DTLS_PSK */
 #ifdef DTLS_PSK
 	  "\t-i file\t\tread PSK identity from file\n"
@@ -320,11 +331,13 @@ usage( const char *program, const char *version) {
 	  "\t-p port\t\tlisten on specified port (default is %d)\n"
 	  "\t-v num\t\tverbosity level (default: 3)\n",
 	   program, version, program, DEFAULT_PORT);
+  cipher_suites_usage(stderr, "\t");
 }
 
 static dtls_handler_t cb = {
   .write = send_to_peer,
   .read  = read_from_peer,
+  .get_cipher_suites = get_cipher_suites,
   .event = NULL,
 #ifdef DTLS_PSK
   .get_psk_info = get_psk_info,
@@ -371,7 +384,7 @@ main(int argc, char **argv) {
   memcpy(psk_key, PSK_DEFAULT_KEY, psk_key_length);
 #endif /* DTLS_PSK */
 
-  while ((opt = getopt(argc, argv, "p:o:v:" PSK_OPTIONS)) != -1) {
+  while ((opt = getopt(argc, argv, "p:o:v:c:" PSK_OPTIONS)) != -1) {
     switch (opt) {
 #ifdef DTLS_PSK
     case 'i' :
@@ -410,6 +423,9 @@ main(int argc, char **argv) {
     case 'v' :
       log_level = strtol(optarg, NULL, 10);
       break;
+    case 'c' :
+      ciphers = init_cipher_suites(optarg);
+      break;
     default:
       usage(argv[0], dtls_package_version());
       exit(1);

tests/dtls-server.c

@@ -14,8 +14,9 @@
 #include <signal.h>
 
 #include "tinydtls.h" 
-#include "dtls.h" 
 #include "dtls_debug.h"
+#include "dtls_ciphers_util.h"
+#include "dtls.h" 
 
 #ifdef IS_WINDOWS
 #include <winsock2.h>
@@ -167,6 +168,16 @@ send_to_peer(struct dtls_context_t *ctx,
 		&session->addr.sa, session->size);
 }
 
+static const dtls_cipher_t* ciphers = NULL;
+
+static void
+get_cipher_suites(struct dtls_context_t *ctx,
+    session_t *session, const dtls_cipher_t **cipher_suites) {
+  (void) ctx;
+  (void) session;
+  *cipher_suites = ciphers;
+}
+
 static int
 dtls_handle_read(struct dtls_context_t *ctx) {
   int *fd;
@@ -256,16 +267,18 @@ usage(const char *program, const char *version) {
 
   fprintf(stderr, "%s v%s -- DTLS server implementation\n"
 	  "(c) 2011-2014 Olaf Bergmann <[email protected]>\n\n"
-	  "usage: %s [-A address] [-p port] [-v num]\n"
+	  "usage: %s [-A address] [-p port] [-v num] [-c cipher-suites]\n"
 	  "\t-A address\t\tlisten on specified address (default is ::)\n"
 	  "\t-p port\t\tlisten on specified port (default is %d)\n"
 	  "\t-v num\t\tverbosity level (default: 3)\n",
 	   program, version, program, DEFAULT_PORT);
+  cipher_suites_usage(stderr, "\t");
 }
 
 static dtls_handler_t cb = {
   .write = send_to_peer,
   .read  = read_from_peer,
+  .get_cipher_suites = get_cipher_suites,
   .event = NULL,
 #ifdef DTLS_PSK
   .get_psk_info = get_psk_info,
@@ -300,7 +313,7 @@ main(int argc, char **argv) {
   listen_addr.sin6_family = AF_INET6;
   listen_addr.sin6_addr = in6addr_any;
 
-  while ((opt = getopt(argc, argv, "A:p:v:")) != -1) {
+  while ((opt = getopt(argc, argv, "A:p:v:c:")) != -1) {
     switch (opt) {
     case 'A' :
       if (resolve_address(optarg, (struct sockaddr *)&listen_addr) < 0) {
@@ -314,6 +327,9 @@ main(int argc, char **argv) {
     case 'v' :
       log_level = strtol(optarg, NULL, 10);
       break;
+    case 'c' :
+      ciphers = init_cipher_suites(optarg);
+      break;
     default:
       usage(argv[0], dtls_package_version());
       exit(1);

tests/dtls_ciphers_util.c

@@ -0,0 +1,83 @@
+/*******************************************************************************
+ *
+ * Copyright (c) 2022 Contributors to the Eclipse Foundation.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * and Eclipse Distribution License v. 1.0 which accompanies this distribution.
+ *
+ * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
+ * and the Eclipse Distribution License is available at
+ * http://www.eclipse.org/org/documents/edl-v10.php.
+ *
+ *******************************************************************************/
+
+#include <string.h>
+
+#include "dtls_ciphers_util.h"
+
+
+struct cipher_entry {
+	const char* name;
+	const dtls_cipher_t cipher;
+};
+
+#define CIPHER_ENTRY(X) { .name = #X, .cipher = X }
+#define ARRAY_LENGTH (sizeof(map)/sizeof(struct cipher_entry))
+#define SEP ':'
+
+static const struct cipher_entry map[] = {
+  CIPHER_ENTRY(TLS_PSK_WITH_AES_128_CCM),
+  CIPHER_ENTRY(TLS_PSK_WITH_AES_128_CCM_8),
+  CIPHER_ENTRY(TLS_ECDHE_ECDSA_WITH_AES_128_CCM),
+  CIPHER_ENTRY(TLS_ECDHE_ECDSA_WITH_AES_128_CCM_8),
+  { .name = NULL, .cipher = TLS_NULL_WITH_NULL_NULL}
+};
+
+static dtls_cipher_t ciphers_table[ARRAY_LENGTH] = { TLS_NULL_WITH_NULL_NULL };
+
+static dtls_cipher_t find_cipher_suite(const char *arg) {
+  for (int index=0; index < ARRAY_LENGTH - 1; ++index) {
+    size_t len = strlen(map[index].name);
+    if (strncmp(arg, map[index].name, len) == 0 && (arg[len] == 0 || arg[len] == SEP)) {
+      return map[index].cipher;
+    }
+  }
+  return TLS_NULL_WITH_NULL_NULL;
+}
+
+static void add_cipher_suite(dtls_cipher_t cipher) {
+  for (int index=0; index < ARRAY_LENGTH - 1; ++index) {
+    if (ciphers_table[index] == cipher) {
+      return;
+    }
+    if (ciphers_table[index] == TLS_NULL_WITH_NULL_NULL) {
+      ciphers_table[index] = cipher;
+      ciphers_table[index + 1] = TLS_NULL_WITH_NULL_NULL;
+      return;
+    }
+  }
+}
+
+const dtls_cipher_t*
+init_cipher_suites(const char* arg) {
+  while (arg) {
+    dtls_cipher_t cipher = find_cipher_suite(arg);
+    if (cipher != TLS_NULL_WITH_NULL_NULL) {
+      add_cipher_suite(cipher);
+    }
+    arg = strchr(arg, SEP);
+    if (arg) {
+      ++arg;
+    }
+  }
+  return ciphers_table;
+}
+
+void
+cipher_suites_usage(FILE* file, const char* head) {
+  fprintf(file, "%s-c ciphers\tlist of cipher-suites separated by ':'\n", head);
+  fprintf(file, "%s\t\t(default: %s:%s\n", head, map[0].name, map[1].name);
+  fprintf(file, "%s\t\t :%s:%s)\n", head, map[2].name, map[3].name);
+}
+

tests/dtls_ciphers_util.h

@@ -0,0 +1,26 @@
+/*******************************************************************************
+ *
+ * Copyright (c) 2022 Contributors to the Eclipse Foundation.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * and Eclipse Distribution License v. 1.0 which accompanies this distribution.
+ *
+ * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
+ * and the Eclipse Distribution License is available at
+ * http://www.eclipse.org/org/documents/edl-v10.php.
+ *
+ *******************************************************************************/
+
+#ifndef _DTLS_CIPHERS_UTIL_H_
+#define _DTLS_CIPHERS_UTIL_H_
+
+#include <stdio.h>
+
+#include "global.h"
+
+const dtls_cipher_t* init_cipher_suites(const char* arg);
+
+void cipher_suites_usage(FILE* file, const char* head);
+
+#endif /* _DTLS_CIPHERS_UTIL_H_ */