tests/net/nanocoap_cli: allow specifying the token

This adds the client_token shell command that allows to specify the
CoAP Token. This is particularly useful to test extended length Tokens,
as enabled with module `nanocoap_token_ext`.

Co-authored-by: benpicco <[email protected]>

tests/net/nanocoap_cli/nanocli_client.c

@@ -81,6 +81,14 @@ static ssize_t _send(coap_pkt_t *pkt, size_t len,
     return nanocoap_request(pkt, NULL, &remote, len);
 }
 
+#if MODULE_NANOCOAP_TOKEN_EXT
+#  define CLIENT_TOKEN_LENGTH_MAX   16
+#else
+#  define CLIENT_TOKEN_LENGTH_MAX   COAP_TOKEN_LENGTH_MAX
+#endif
+static uint8_t _client_token[CLIENT_TOKEN_LENGTH_MAX] = {0xDA, 0xEC};
+static uint8_t _client_token_len = 2;
+
 static int _cmd_client(int argc, char **argv)
 {
     /* Ordered like the RFC method code numbers, but off by 1. GET is code 0. */
@@ -89,7 +97,6 @@ static int _cmd_client(int argc, char **argv)
     uint8_t buf[buflen];
     coap_pkt_t pkt;
     size_t len;
-    uint8_t token[2] = {0xDA, 0xEC};
 
     if (argc == 1) {
         /* show help for commands */
@@ -110,7 +117,8 @@ static int _cmd_client(int argc, char **argv)
 
     /* parse options */
     if (argc == 5 || argc == 6) {
-        ssize_t hdrlen = coap_build_hdr(pkt.hdr, COAP_TYPE_CON, &token[0], 2,
+        ssize_t hdrlen = coap_build_hdr(pkt.hdr, COAP_TYPE_CON,
+                                        _client_token, _client_token_len,
                                         code_pos+1, 1);
         coap_pkt_init(&pkt, &buf[0], buflen, hdrlen);
         coap_opt_add_string(&pkt, COAP_OPT_URI_PATH, argv[4], '/');
@@ -165,9 +173,33 @@ static int _cmd_client(int argc, char **argv)
            argv[0]);
     return 1;
 }
-
 SHELL_COMMAND(client, "CoAP client", _cmd_client);
 
+static int _cmd_client_token(int argc, char **argv){
+    if (argc != 2) {
+        printf("Usage: %s <TOKEN_HEX>\n", argv[0]);
+        return 1;
+    }
+
+    ssize_t tkl = scn_buf_hex(_client_token, sizeof(_client_token),
+                              argv[1], strlen(argv[1]));
+
+    if (tkl == -EOVERFLOW) {
+        puts("Token too long");
+        return 1;
+    }
+
+    if (tkl < 0) {
+        puts("Failed to parse token");
+        return 1;
+    }
+
+    _client_token_len = tkl;
+
+    return 0;
+}
+SHELL_COMMAND(client_token, "Set Token for CoAP client", _cmd_client_token);
+
 static int _blockwise_cb(void *arg, size_t offset, uint8_t *buf,
                          size_t len, int more)
 {