Add support for UDP control sockt for UDP tests (no use of TCP)

Author: davidBar-On

src/iperf.h

@@ -295,6 +295,7 @@ struct iperf_test
     int       sender_has_retransmits;
     int       other_side_has_retransmits;       /* used if mode == BIDIRECTIONAL */
     struct protocol *protocol;
+    int      udp_ctrl_sck;                      /* --udp-cntl-sck - true if control socket is UDP */
     signed char state;
     char     *server_hostname;                  /* -c option */
     char     *tmp_template;

src/iperf_api.c

@@ -1158,6 +1158,7 @@ iperf_parse_arguments(struct iperf_test *test, int argc, char **argv)
 #if defined(HAVE_IPPROTO_MPTCP)
         {"mptcp", no_argument, NULL, 'm'},
 #endif
+        {"udp-control", no_argument, NULL, OPT_UDP_CONTROL},
         {"debug", optional_argument, NULL, 'd'},
         {"help", no_argument, NULL, 'h'},
         {NULL, 0, NULL, 0}
@@ -1662,6 +1663,9 @@ iperf_parse_arguments(struct iperf_test *test, int argc, char **argv)
 		test->mptcp = 1;
 		break;
 #endif
+            case OPT_UDP_CONTROL:
+                test->udp_ctrl_sck = 1;
+                break;
 	    case 'h':
 		usage_long(stdout);
 		exit(0);
@@ -1784,6 +1788,11 @@ iperf_parse_arguments(struct iperf_test *test, int argc, char **argv)
     }
     test->settings->blksize = blksize;
 
+    if (test->role == 'c' && test->udp_ctrl_sck && test->protocol->id != Pudp) {
+        i_errno = IEUDPCNTLONLYUDP;
+        return -1;
+    }
+
     if (!rate_flag)
 	test->settings->rate = test->protocol->id == Pudp ? UDP_RATE : 0;
 
@@ -3112,6 +3121,8 @@ iperf_defaults(struct iperf_test *testp)
 
     set_protocol(testp, Ptcp);
 
+    testp->udp_ctrl_sck = 0;
+
 #if defined(HAVE_SCTP_H)
     sctp = protocol_new();
     if (!sctp) {

src/iperf_api.h

@@ -101,6 +101,7 @@ typedef atomic_uint_fast64_t atomic_iperf_size_t;
 #define OPT_JSON_STREAM 28
 #define OPT_SND_TIMEOUT 29
 #define OPT_USE_PKCS1_PADDING 30
+#define OPT_UDP_CONTROL 31
 
 /* states */
 #define TEST_START 1
@@ -421,6 +422,7 @@ enum {
     IESNDTIMEOUT = 33,      // Illegal message send timeout
     IEUDPFILETRANSFER = 34, // Cannot transfer file using UDP
     IESERVERAUTHUSERS = 35,  // Cannot access authorized users file
+    IEUDPCNTLONLYUDP = 36,  // UDP Control Socket is supported only in UDP test
     /* Test errors */
     IENEWTEST = 100,        // Unable to create a new test (check perror)
     IEINITTEST = 101,       // Test initialization failed (check perror)

src/iperf_client_api.c

@@ -40,6 +40,7 @@
 
 #include "iperf.h"
 #include "iperf_api.h"
+#include "iperf_udp.h"
 #include "iperf_util.h"
 #include "iperf_locale.h"
 #include "iperf_time.h"
@@ -316,8 +317,7 @@ iperf_handle_message_client(struct iperf_test *test)
         iperf_printf(test, "Reading new State from the Server - current state is %d-%s\n", test->state, state_to_text(test->state));
     }
 
-    /*!!! Why is this read() and not Nread()? */
-    if ((rval = read(test->ctrl_sck, (char*) &test->state, sizeof(signed char))) <= 0) {
+    if ((rval = Nread(test->ctrl_sck, (char*) &test->state, sizeof(signed char), Ptcp)) <= 0) {
         if (rval == 0) {
             i_errno = IECTRLCLOSE;
             return -1;
@@ -429,29 +429,36 @@ iperf_connect(struct iperf_test *test)
     make_cookie(test->cookie);
 
     /* Create and connect the control channel */
-    if (test->ctrl_sck < 0)
-	// Create the control channel using an ephemeral port
-	test->ctrl_sck = netdial(test->settings->domain, Ptcp, test->bind_address, test->bind_dev, 0, test->server_hostname, test->server_port, test->settings->connect_timeout);
     if (test->ctrl_sck < 0) {
-        i_errno = IECONNECT;
-        return -1;
-    }
-
-    // set TCP_NODELAY for lower latency on control messages
-    int flag = 1;
-    if (setsockopt(test->ctrl_sck, IPPROTO_TCP, TCP_NODELAY, (char *) &flag, sizeof(int))) {
-        i_errno = IESETNODELAY;
-        return -1;
-    }
-
+	// Create the control channel using an ephemeral port
+        if (test->udp_ctrl_sck) { // UDP Control Socket
+            test->ctrl_sck = iperf_udp_connect(test);
+            if (test->ctrl_sck < 0) {
+                i_errno = IECONNECT;
+                return -1;
+            }
+        } else { // TCP Control Socket
+            test->ctrl_sck = netdial(test->settings->domain, Ptcp, test->bind_address, test->bind_dev, 0, test->server_hostname, test->server_port, test->settings->connect_timeout);
+            if (test->ctrl_sck < 0) {
+                i_errno = IECONNECT;
+                return -1;
+            }
+            // set TCP_NODELAY for lower latency on control messages
+            int flag = 1;
+            if (setsockopt(test->ctrl_sck, IPPROTO_TCP, TCP_NODELAY, (char *) &flag, sizeof(int))) {
+                i_errno = IESETNODELAY;
+                return -1;
+            }
 #if defined(HAVE_TCP_USER_TIMEOUT)
-    if ((opt = test->settings->snd_timeout)) {
-        if (setsockopt(test->ctrl_sck, IPPROTO_TCP, TCP_USER_TIMEOUT, &opt, sizeof(opt)) < 0) {
-        i_errno = IESETUSERTIMEOUT;
-        return -1;
+            if ((opt = test->settings->snd_timeout)) {
+                if (setsockopt(test->ctrl_sck, IPPROTO_TCP, TCP_USER_TIMEOUT, &opt, sizeof(opt)) < 0) {
+                    i_errno = IESETUSERTIMEOUT;
+                    return -1;
+                }
+            }
+#endif /* HAVE_TCP_USER_TIMEOUT */
         }
     }
-#endif /* HAVE_TCP_USER_TIMEOUT */
 
     if (Nwrite(test->ctrl_sck, test->cookie, COOKIE_SIZE, Ptcp) < 0) {
         i_errno = IESENDCOOKIE;
@@ -461,21 +468,22 @@ iperf_connect(struct iperf_test *test)
     FD_SET(test->ctrl_sck, &test->read_set);
     if (test->ctrl_sck > test->max_fd) test->max_fd = test->ctrl_sck;
 
-    len = sizeof(opt);
-    if (getsockopt(test->ctrl_sck, IPPROTO_TCP, TCP_MAXSEG, &opt, &len) < 0) {
-        test->ctrl_sck_mss = 0;
-    }
-    else {
-        if (opt > 0 && opt <= MAX_UDP_BLOCKSIZE) {
-            test->ctrl_sck_mss = opt;
+    if (!test->udp_ctrl_sck) { // TCP Control Socket
+        len = sizeof(opt);
+        if (getsockopt(test->ctrl_sck, IPPROTO_TCP, TCP_MAXSEG, &opt, &len) < 0) {
+            test->ctrl_sck_mss = 0;
         }
         else {
-            char str[WARN_STR_LEN];
-            snprintf(str, sizeof(str),
-                     "Ignoring nonsense TCP MSS %d", opt);
-            warning(str);
-
-            test->ctrl_sck_mss = 0;
+            if (opt > 0 && opt <= MAX_UDP_BLOCKSIZE) {
+                test->ctrl_sck_mss = opt;
+            } else {
+                char str[WARN_STR_LEN];
+                snprintf(str, sizeof(str),
+                        "Ignoring nonsense TCP MSS %d", opt);
+                warning(str);
+
+                test->ctrl_sck_mss = 0;
+            }
         }
     }
 

src/iperf_error.c

@@ -188,6 +188,9 @@ iperf_strerror(int int_errno)
         case IEUDPBLOCKSIZE:
             snprintf(errstr, len, "block size invalid (minimum = %d bytes, maximum = %d bytes)", MIN_UDP_BLOCKSIZE, MAX_UDP_BLOCKSIZE);
             break;
+        case IEUDPCNTLONLYUDP:
+            snprintf(errstr, len, "UDP Control Socket is supported only in UDP test");
+            break;
         case IEBADTOS:
             snprintf(errstr, len, "bad TOS value (must be between 0 and 255 inclusive)");
             break;

src/iperf_locale.c

@@ -131,6 +131,7 @@ const char usage_longstr[] = "Usage: iperf3 [-s|-c host] [options]\n"
 #if defined(HAVE_IPPROTO_MPTCP)
                            "  -m, --mptcp               use MPTCP rather than plain TCP\n"
 #endif
+                           "  --udp-control             use UDP for the control socket (instead of default TCP)\n"
                            "  -d, --debug[=#]           emit debugging output\n"
                            "                            (optional optional \"=\" and debug level: 1-4. Default is 4 - all messages)\n"
                            "  -v, --version             show version information and quit\n"

src/iperf_server_api.c

@@ -112,8 +112,10 @@ iperf_server_worker_run(void *s) {
 int
 iperf_server_listen(struct iperf_test *test)
 {
+    int proto = (test->udp_ctrl_sck) ? Pudp : Ptcp;
+
     retry:
-    if((test->listener = netannounce(test->settings->domain, Ptcp, test->bind_address, test->bind_dev, test->server_port)) < 0) {
+    if((test->listener = netannounce(test->settings->domain, proto, test->bind_address, test->bind_dev, test->server_port)) < 0) {
 	if (errno == EAFNOSUPPORT && (test->settings->domain == AF_INET6 || test->settings->domain == AF_UNSPEC)) {
 	    /* If we get "Address family not supported by protocol", that
 	    ** probably means we were compiled with IPv6 but the running
@@ -157,32 +159,50 @@ iperf_accept(struct iperf_test *test)
     signed char rbuf = ACCESS_DENIED;
     socklen_t len;
     struct sockaddr_storage addr;
+    int rc;
 
-    len = sizeof(addr);
-    if ((s = accept(test->listener, (struct sockaddr *) &addr, &len)) < 0) {
-        i_errno = IEACCEPT;
-        return ret;
+    if (test->udp_ctrl_sck) { // UDP Control Socket
+        s = test->listener;
+    }
+    else { // TCP Control Socket
+        len = sizeof(addr);
+        if ((s = accept(test->listener, (struct sockaddr *) &addr, &len)) < 0) {
+            i_errno = IEACCEPT;
+            return ret;
+        }
+    }
+
+    /* UDP listener socket should be accepted to allow communication (including for sending Deny) */
+    if (test->udp_ctrl_sck) { // UDP Control Socket
+        if (test->debug_level >= DEBUG_LEVEL_INFO) {
+            printf("Accepting new Connection Request over UDP socket %d\n", s);
+        }
+        if ((rc = iperf_udp_accept_socket(test, s)) < 0) {
+            return rc;
+        }
     }
 
     if (test->ctrl_sck == -1) {
         /* Server free, accept new client */
         test->ctrl_sck = s;
-        // set TCP_NODELAY for lower latency on control messages
-        int flag = 1;
-        if (setsockopt(test->ctrl_sck, IPPROTO_TCP, TCP_NODELAY, (char *) &flag, sizeof(int))) {
-            i_errno = IESETNODELAY;
-            goto error_handling;
-        }
+        if (!test->udp_ctrl_sck) { // TCP Control Socket
+            // set TCP_NODELAY for lower latency on control messages
+            int flag = 1;
+            if (setsockopt(test->ctrl_sck, IPPROTO_TCP, TCP_NODELAY, (char *) &flag, sizeof(int))) {
+                i_errno = IESETNODELAY;
+                goto error_handling;
+            }
 
 #if defined(HAVE_TCP_USER_TIMEOUT)
-        int opt;
-        if ((opt = test->settings->snd_timeout)) {
-            if (setsockopt(s, IPPROTO_TCP, TCP_USER_TIMEOUT, &opt, sizeof(opt)) < 0) {
-                i_errno = IESETUSERTIMEOUT;
-                goto error_handling;
+            int opt;
+            if ((opt = test->settings->snd_timeout)) {
+                if (setsockopt(s, IPPROTO_TCP, TCP_USER_TIMEOUT, &opt, sizeof(opt)) < 0) {
+                    i_errno = IESETUSERTIMEOUT;
+                    goto error_handling;
+                }
             }
-        }
 #endif /* HAVE_TCP_USER_TIMEOUT */
+        }
 
         if (Nread(test->ctrl_sck, test->cookie, COOKIE_SIZE, Ptcp) != COOKIE_SIZE) {
             /*
@@ -220,6 +240,24 @@ iperf_accept(struct iperf_test *test)
             if (test->debug)
                 printf("successfully sent ACCESS_DENIED to an unsolicited connection request during active test\n");
         }
+
+        // Create new UDP listener socket.  Done before closing the previous listener socket to allow the
+        // ACCESS_DENIED message to be sent out of the server before the socket is closed.
+        if (test->udp_ctrl_sck) {
+            FD_CLR(s, &test->read_set);
+            if (test->debug_level >= DEBUG_LEVEL_INFO) {
+                printf("Creating new UDP Listener socket\n");
+            }
+            if ((test->listener = iperf_udp_listen(test)) < 0) {
+                return -1;
+            }
+            if (test->debug_level >= DEBUG_LEVEL_INFO) {
+                printf("Created new UDP Listener socket=%d\n", test->listener);
+            }
+            FD_SET(test->listener, &test->read_set);
+            test->max_fd = (test->max_fd < test->listener) ? test->listener : test->max_fd;
+        }
+
         close(s);
     }
     return 0;
@@ -839,9 +877,14 @@ iperf_run_server(struct iperf_test *test)
 
                 if (rec_streams_accepted == streams_to_rec && send_streams_accepted == streams_to_send) {
                     if (test->protocol->id != Ptcp) {
-                        FD_CLR(test->prot_listener, &test->read_set);
-                        close(test->prot_listener);
-                        test->prot_listener = -1;
+                        if (test->udp_ctrl_sck) {
+                            test->listener = test->prot_listener;
+                            test->prot_listener = -1;
+                        } else {
+                            FD_CLR(test->prot_listener, &test->read_set);
+                            close(test->prot_listener);
+                            test->prot_listener = -1;
+                        }
                     } else {
                         if (test->no_delay || test->settings->mss || test->settings->socket_bufsize) {
                             FD_CLR(test->listener, &test->read_set);