examples/gcoap: add handling of proxied requests

examples/gcoap/gcoap_cli.c

@@ -30,6 +30,10 @@
 #define ENABLE_DEBUG (0)
 #include "debug.h"
 
+static bool _proxied = false;
+static sock_udp_ep_t _proxy_remote;
+static char proxy_uri[64];
+
 static ssize_t _encode_link(const coap_resource_t *resource, char *buf,
                             size_t maxlen, coap_link_encoder_ctx_t *context);
 static void _resp_handler(const gcoap_request_memo_t *memo, coap_pkt_t* pdu,
@@ -58,7 +62,7 @@ static gcoap_listener_t _listener = {
 /* Retain request path to re-request if response includes block. User must not
  * start a new request (with a new path) until any blockwise transfer
  * completes or times out. */
-#define _LAST_REQ_PATH_MAX (32)
+#define _LAST_REQ_PATH_MAX (64)
 static char _last_req_path[_LAST_REQ_PATH_MAX];
 
 /* Counts requests sent by CLI. */
@@ -137,13 +141,25 @@ static void _resp_handler(const gcoap_request_memo_t *memo, coap_pkt_t* pdu,
                 return;
             }
 
+            if (_proxied) {
+                gcoap_req_init(pdu, (uint8_t *)pdu->hdr, CONFIG_GCOAP_PDU_BUF_SIZE,
+                               COAP_METHOD_GET, NULL);
+            }
+            else {
                 gcoap_req_init(pdu, (uint8_t *)pdu->hdr, CONFIG_GCOAP_PDU_BUF_SIZE,
                                COAP_METHOD_GET, _last_req_path);
+            }
+
             if (msg_type == COAP_TYPE_ACK) {
                 coap_hdr_set_type(pdu->hdr, COAP_TYPE_CON);
             }
             block.blknum++;
             coap_opt_add_block2_control(pdu, &block);
+
+            if (_proxied) {
+                coap_opt_add_proxy_uri(pdu, _last_req_path);
+            }
+
             int len = coap_opt_finish(pdu, COAP_OPT_FINISH_NONE);
             gcoap_req_send((uint8_t *)pdu->hdr, len, remote,
                            _resp_handler, memo->context);
@@ -214,52 +230,70 @@ static ssize_t _riot_board_handler(coap_pkt_t *pdu, uint8_t *buf, size_t len, vo
     }
 }
 
-static size_t _send(uint8_t *buf, size_t len, char *addr_str, char *port_str)
+static bool _parse_endpoint(sock_udp_ep_t *remote,
+                            char *addr_str, char *port_str)
 {
     ipv6_addr_t addr;
-    size_t bytes_sent;
+    remote->family = AF_INET6;
-    sock_udp_ep_t remote;
-
-    remote.family = AF_INET6;
 
     /* parse for interface */
     char *iface = ipv6_addr_split_iface(addr_str);
     if (!iface) {
         if (gnrc_netif_numof() == 1) {
             /* assign the single interface found in gnrc_netif_numof() */
-            remote.netif = (uint16_t)gnrc_netif_iter(NULL)->pid;
+            remote->netif = (uint16_t)gnrc_netif_iter(NULL)->pid;
         }
         else {
-            remote.netif = SOCK_ADDR_ANY_NETIF;
+            remote->netif = SOCK_ADDR_ANY_NETIF;
         }
     }
     else {
         int pid = atoi(iface);
         if (gnrc_netif_get_by_pid(pid) == NULL) {
             puts("gcoap_cli: interface not valid");
-            return 0;
+            return false;
         }
-        remote.netif = pid;
+        remote->netif = pid;
     }
     /* parse destination address */
     if (ipv6_addr_from_str(&addr, addr_str) == NULL) {
         puts("gcoap_cli: unable to parse destination address");
-        return 0;
+        return false;
     }
-    if ((remote.netif == SOCK_ADDR_ANY_NETIF) && ipv6_addr_is_link_local(&addr)) {
+    if ((remote->netif == SOCK_ADDR_ANY_NETIF) && ipv6_addr_is_link_local(&addr)) {
         puts("gcoap_cli: must specify interface for link local target");
-        return 0;
+        return false;
     }
-    memcpy(&remote.addr.ipv6[0], &addr.u8[0], sizeof(addr.u8));
+    memcpy(&remote->addr.ipv6[0], &addr.u8[0], sizeof(addr.u8));
 
     /* parse port */
-    remote.port = atoi(port_str);
+    remote->port = atoi(port_str);
-    if (remote.port == 0) {
+    if (remote->port == 0) {
         puts("gcoap_cli: unable to parse destination port");
-        return 0;
+        return false;
     }
 
-    bytes_sent = gcoap_req_send(buf, len, &remote, _resp_handler, NULL);
+    return true;
+}
+
+static size_t _send(uint8_t *buf, size_t len, char *addr_str, char *port_str)
+{
+    size_t bytes_sent;
+
+    sock_udp_ep_t *remote;
+
+    if (_proxied) {
+        remote = &_proxy_remote;
+    }
+    else {
+        sock_udp_ep_t new_remote;
+        if (!_parse_endpoint(&new_remote, addr_str, port_str)) {
+            return 0;
+        }
+        remote = &new_remote;
+    }
+
+    bytes_sent = gcoap_req_send(buf, len, remote, _resp_handler, NULL);
     if (bytes_sent > 0) {
         req_count++;
     }
@@ -285,10 +319,40 @@ int gcoap_cli_cmd(int argc, char **argv)
         printf("CoAP server is listening on port %u\n", CONFIG_GCOAP_PORT);
         printf(" CLI requests sent: %u\n", req_count);
         printf("CoAP open requests: %u\n", open_reqs);
+        printf("Configured Proxy: ");
+        if (_proxied) {
+            char addrstr[IPV6_ADDR_MAX_STR_LEN];
+            printf("[%s]:%u\n",
+                   ipv6_addr_to_str(addrstr,
+                                    (ipv6_addr_t *) &_proxy_remote.addr.ipv6,
+                                    sizeof(addrstr)),
+                   _proxy_remote.port);
+        }
+        else {
+            puts("None");
+        }
         return 0;
     }
+    else if (strcmp(argv[1], "proxy") == 0) {
+        if ((argc == 5) && (strcmp(argv[2], "set") == 0)) {
+            if (!_parse_endpoint(&_proxy_remote, argv[3], argv[4])) {
+                puts("Could not set proxy");
+                return 1;
+            }
+            _proxied = true;
+            return 0;
+        }
+        if ((argc == 3) && (strcmp(argv[2], "unset") == 0)) {
+            memset(&_proxy_remote, 0, sizeof(_proxy_remote));
+            _proxied = false;
+            return 0;
+        }
+        printf("usage: %s proxy set <addr>[%%iface] <port>\n", argv[0]);
+        printf("       %s proxy unset\n", argv[0]);
+        return 1;
+    }
 
-    /* if not 'info', must be a method code */
+    /* if not 'info' and 'proxy', must be a method code */
     int code_pos = -1;
     for (size_t i = 0; i < ARRAY_SIZE(method_codes); i++) {
         if (strcmp(argv[1], method_codes[i]) == 0) {
@@ -314,17 +378,36 @@ int gcoap_cli_cmd(int argc, char **argv)
      */
     if (((argc == apos + 3) && (code_pos == 0)) ||
         ((argc == apos + 4) && (code_pos != 0))) {
-        gcoap_req_init(&pdu, &buf[0], CONFIG_GCOAP_PDU_BUF_SIZE, code_pos+1, argv[apos+2]);
+
+        char *uri = argv[apos+2];
+        int uri_len = strlen(argv[apos+2]);
+
+        if (_proxied) {
+            uri_len = snprintf(proxy_uri, 64, "coap://[%s]:%s%s", argv[apos], argv[apos+1], uri);
+            uri = proxy_uri;
+
+            gcoap_req_init(&pdu, &buf[0], CONFIG_GCOAP_PDU_BUF_SIZE, code_pos+1, NULL);
+        }
+        else{
+            gcoap_req_init(&pdu, &buf[0], CONFIG_GCOAP_PDU_BUF_SIZE, code_pos+1, uri);
+        }
         coap_hdr_set_type(pdu.hdr, msg_type);
 
         memset(_last_req_path, 0, _LAST_REQ_PATH_MAX);
-        if (strlen(argv[apos+2]) < _LAST_REQ_PATH_MAX) {
+        if (uri_len < _LAST_REQ_PATH_MAX) {
-            memcpy(_last_req_path, argv[apos+2], strlen(argv[apos+2]));
+            memcpy(_last_req_path, uri, uri_len);
         }
 
         size_t paylen = (argc == apos + 4) ? strlen(argv[apos+3]) : 0;
         if (paylen) {
             coap_opt_add_format(&pdu, COAP_FORMAT_TEXT);
+        }
+
+        if (_proxied) {
+            coap_opt_add_proxy_uri(&pdu, uri);
+        }
+
+        if (paylen) {
             len = coap_opt_finish(&pdu, COAP_OPT_FINISH_PAYLOAD);
             if (pdu.payload_len >= paylen) {
                 memcpy(pdu.payload, argv[apos+3], paylen);
@@ -374,7 +457,7 @@ int gcoap_cli_cmd(int argc, char **argv)
     }
 
     end:
-    printf("usage: %s <get|post|put|info>\n", argv[0]);
+    printf("usage: %s <get|post|put|proxy|info>\n", argv[0]);
     return 1;
 }