Fix issue #1157 (partial) - support bind device using

src/iperf_api.c

@@ -1019,6 +1019,8 @@ iperf_parse_arguments(struct iperf_test *test, int argc, char **argv)
     char* comma;
 #endif /* HAVE_CPU_AFFINITY */
     char* slash;
+    char *p, *p1;
+    struct in6_addr ipv6_addr;
     struct xbind_entry *xbe;
     double farg;
     int rcv_timeout_in = 0;
@@ -1101,6 +1103,26 @@ iperf_parse_arguments(struct iperf_test *test, int argc, char **argv)
                 }
 		iperf_set_test_role(test, 'c');
 		iperf_set_test_server_hostname(test, optarg);
+                // hostname should be extended with `%<dev>` for IPv6 link-local addresses
+                if ((p = strtok(optarg, "%")) != NULL) {
+                    p1 = strtok(NULL, "%");
+                    if (inet_pton(AF_INET6, p, &ipv6_addr) == 1) {
+                        if (IN6_IS_ADDR_LINKLOCAL(&ipv6_addr)) {
+                            if (!p1) {
+                                i_errno = IEHOSTDEV;
+                            }
+                        } else if (p1) {
+                            i_errno = IEHOSTDEV;
+                        }
+                    } else {    //IPv4
+                        if (p1) {
+                            i_errno = IEHOSTDEV;
+                        }
+                    }
+                    if (i_errno ==  IEHOSTDEV) {
+                        return -1;
+                    }                   
+                }
                 break;
             case 'u':
                 set_protocol(test, Pudp);
@@ -1213,7 +1235,20 @@ iperf_parse_arguments(struct iperf_test *test, int argc, char **argv)
 		client_flag = 1;
                 break;
             case 'B':
-                test->bind_address = strdup(optarg);
+                // IP ddress format is <addr>[%<device>]
+                if ((p = strtok(optarg, "%")) == NULL)
+                    test->bind_address = strdup(optarg);
+                else {
+                    test->bind_address = strdup(p);
+                    if ((p = strtok(NULL, "%")) != NULL) {
+#if defined (HAVE_SO_BINDTODEVICE)
+                        test->bind_dev = strdup(p);
+#else /* HAVE_SO_BINDTODEVICE */
+		        i_errno = IEBINDDEVNOSUPPORT;
+		        return -1;
+#endif /* HAVE_SO_BINDTODEVICE */
+                    }
+                }
                 break;
 #if defined (HAVE_SO_BINDTODEVICE)
             case OPT_BIND_DEV:

src/iperf_api.h

@@ -425,7 +425,9 @@ enum {
     IEAUTHTEST = 142,       // Test authorization failed
     IEBINDDEV = 143,        // Unable to bind-to-device (check perror, maybe permissions?)
     IENOMSG = 144,          // No message was received for NO_MSG_RCVD_TIMEOUT time period
-    IESETDONTFRAGMENT = 145,    // Unable to set IP Do-Not-Fragment
+    IESETDONTFRAGMENT = 145,   // Unable to set IP Do-Not-Fragment
+    IEBINDDEVNOSUPPORT = 146,  // `ip%%dev` is not supported as system does not support bind to device
+    IEHOSTDEV = 147,        // host device name (ip%%<dev>) is supported (and required) only for IPv6 link-local address
     /* Stream errors */
     IECREATESTREAM = 200,   // Unable to create a new stream (check herror/perror)
     IEINITSTREAM = 201,     // Unable to initialize stream (check herror/perror)

src/iperf_error.c

@@ -438,6 +438,15 @@ iperf_strerror(int int_errno)
 	case IEIDLETIMEOUT:
 	    snprintf(errstr, len, "idle timeout parameter is not positive or larget then allowed limit");
             break;
+	case IEBINDDEV:
+	    snprintf(errstr, len, "Unable to bind-to-device (check perror, maybe permissions?)");
+            break;
+    case IEBINDDEVNOSUPPORT:
+	    snprintf(errstr, len, "`<ip>%%<dev>` is not supported as system does not support bind to device");
+            break;
+    case IEHOSTDEV:
+	    snprintf(errstr, len, "host device name (ip%%<dev>) is supported (and required) only for IPv6 link-local address");
+            break;        
 	case IENOMSG:
 	    snprintf(errstr, len, "idle timeout for receiving data");
             break;

src/iperf_locale.c

@@ -105,9 +105,12 @@ const char usage_longstr[] = "Usage: iperf3 [-s|-c host] [options]\n"
 #if defined(HAVE_CPU_AFFINITY)
                            "  -A, --affinity n/n,m      set CPU affinity\n"
 #endif /* HAVE_CPU_AFFINITY */
-                           "  -B, --bind      <host>    bind to the interface associated with the address <host>\n"
 #if defined(HAVE_SO_BINDTODEVICE)
-                           "  --bind-dev      <dev>     bind to the network interface with SO_BINDTODEVICE\n"
+                           "  -B, --bind <host>[%<dev>] bind to the interface associated with the address <host>\n"
+                           "                            (optional <dev> equivalent to `--bind-dev <dev>`)\n"
+                           "  --bind-dev <dev>          bind to the network interface with SO_BINDTODEVICE\n"
+#else /* HAVE_SO_BINDTODEVICE */
+                           "  -B, --bind      <host>    bind to the interface associated with the address <host>\n"
 #endif /* HAVE_SO_BINDTODEVICE */
                            "  -V, --verbose             more detailed output\n"
                            "  -J, --json                output in JSON format\n"
@@ -139,7 +142,8 @@ const char usage_longstr[] = "Usage: iperf3 [-s|-c host] [options]\n"
                            "                            and client during the authentication process\n"
 #endif //HAVE_SSL
                            "Client specific:\n"
-                           "  -c, --client    <host>    run in client mode, connecting to <host>\n"
+                           "  -c, --client <host>[%<dev>] run in client mode, connecting to <host>\n"
+                           "                              %<dev> is supported and required when <host> is IPv6 Link-local\n"
 #if defined(HAVE_SCTP_H)
                            "  --sctp                    use SCTP rather than TCP\n"
                            "  -X, --xbind <name>        bind SCTP association to links\n"