tests/nanocoap_cli: add DTLS support

tests/nanocoap_cli/Makefile

@@ -22,22 +22,27 @@ LOW_MEMORY_BOARDS := \
   blackpill-stm32f103c8 \
   bluepill-stm32f103c8 \
   derfmega128 \
+  im880b \
   nucleo-f302r8 \
   saml10-xpro \
   saml11-xpro \
+  spark-core \
   stm32f7508-dk \
   stm32mp157c-dk2 \
   #
 
-# Don't enable VFS functions on small boards
+# Don't enable VFS, DTLS functions on small boards
 ifeq (,$(filter $(BOARD),$(LOW_MEMORY_BOARDS)))
+  USEMODULE += nanocoap_dtls
+  USEMODULE += prng_sha256prng
+
   USEMODULE += nanocoap_vfs
   USEMODULE += vfs_default
   # USEMODULE += vfs_auto_format
   USEMODULE += shell_cmds_default
 
-  # VFS operations require more stack on the main thread
-  CFLAGS += -DTHREAD_STACKSIZE_MAIN=THREAD_STACKSIZE_LARGE
+  # DTLS and VFS operations require more stack on the main thread
+  CFLAGS += -DTHREAD_STACKSIZE_MAIN=\(3*THREAD_STACKSIZE_DEFAULT\)
 
   # always enable auto-format for native
   ifeq ($(BOARD),native)

tests/nanocoap_cli/main.c

@@ -21,6 +21,7 @@
 #include <stdio.h>
 #include "msg.h"
 
+#include "net/nanocoap_sock.h"
 #include "net/gnrc/netif.h"
 #include "net/ipv6/addr.h"
 #include "shell.h"
@@ -28,6 +29,25 @@
 #define MAIN_QUEUE_SIZE (4)
 static msg_t _main_msg_queue[MAIN_QUEUE_SIZE];
 
+#if IS_USED(MODULE_NANOCOAP_DTLS)
+#include "net/credman.h"
+#include "net/dsm.h"
+#include "tinydtls_keys.h"
+
+static const uint8_t psk_id_0[] = PSK_DEFAULT_IDENTITY;
+static const uint8_t psk_key_0[] = PSK_DEFAULT_KEY;
+static const credman_credential_t credential = {
+    .type = CREDMAN_TYPE_PSK,
+    .tag = CONFIG_NANOCOAP_SOCK_DTLS_TAG,
+    .params = {
+        .psk = {
+            .key = { .s = psk_key_0, .len = sizeof(psk_key_0) - 1, },
+            .id = { .s = psk_id_0, .len = sizeof(psk_id_0) - 1, },
+        }
+    },
+};
+#endif
+
 extern int nanotest_client_cmd(int argc, char **argv);
 extern int nanotest_client_url_cmd(int argc, char **argv);
 extern int nanotest_server_cmd(int argc, char **argv);
@@ -121,6 +141,14 @@ int main(void)
     msg_init_queue(_main_msg_queue, MAIN_QUEUE_SIZE);
     puts("nanocoap test app");
 
+#if IS_USED(MODULE_NANOCOAP_DTLS)
+    int res = credman_add(&credential);
+    if (res < 0 && res != CREDMAN_EXIST) {
+        printf("nanocoap: cannot add credential to system: %d\n", res);
+        return res;
+    }
+#endif
+
     /* start shell */
     puts("All up, running the shell now");
     char line_buf[SHELL_DEFAULT_BUFSIZE];

tests/nanocoap_cli/tinydtls_keys.h

@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2018 Inria
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     examples
+ * @{
+ *
+ * @file
+ * @brief       PSK and RPK keys for the dtls-sock example.
+ *
+ * @author      Raul Fuentes <raul.fuentes-samaniego@inria.fr>
+ *
+ * @}
+ */
+
+#ifndef TINYDTLS_KEYS_H
+#define TINYDTLS_KEYS_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ *  Default keys examples for tinyDTLS (for RIOT, Linux and Contiki)
+ */
+#define PSK_DEFAULT_IDENTITY "Client_identity"
+#define PSK_DEFAULT_KEY "secretPSK"
+#define PSK_OPTIONS "i:k:"
+#define PSK_ID_MAXLEN 32
+#define PSK_MAXLEN 32
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* TINYDTLS_KEYS_H */