Add -X to restrict SCTP binding to a subset of interfaces.

Contains an alternate implementation of previously-submitted patches
to set the maximum segment size and no-delay options.

As a result of this change, SCTP functionality on Linux will generally
require the libsctp library (on CentOS and similar distributions this
is provided by the lksctp-tools RPM).

Part of esnet#131.

Submitted by:	Bruce Simpson <[email protected]>

configure.ac

@@ -1,4 +1,4 @@
-# iperf, Copyright (c) 2014, The Regents of the University of
+# iperf, Copyright (c) 2014, 2015, The Regents of the University of
 # California, through Lawrence Berkeley National Laboratory (subject
 # to receipt of any required approvals from the U.S. Dept. of
 # Energy).  All rights reserved.
@@ -86,7 +86,8 @@ AC_C_CONST
 # Check for SCTP support
 AC_CHECK_HEADERS([sys/socket.h])
 AC_CHECK_HEADERS([netinet/sctp.h],
-		 AC_DEFINE([HAVE_SCTP], [1], [Have SCTP support.]),
+		 AC_DEFINE([HAVE_SCTP], [1], [Have SCTP support.])
+		 AC_SEARCH_LIBS(sctp_bindx, [sctp]),
 		 [],
 		 [#ifdef HAVE_SYS_SOCKET_H
 #include <sys/socket.h>

docs/dev.rst

@@ -228,8 +228,8 @@ Code Authors
 The main authors of iperf3 are (in alphabetical order):  Jon Dugan,
 Seth Elliott, Bruce A. Mah, Jeff Poskanzer, Kaustubh Prabhu.
 Additional code contributions have come from (also in alphabetical
-order):  Mark Ashley, Aaron Brown, Aeneas Jaißle, Susant Sahani, Brian
-Tierney.
+order):  Mark Ashley, Aaron Brown, Aeneas Jaißle, Susant Sahani, 
+Bruce Simpson, Brian Tierney.
 
 iperf3 contains some original code from iperf2.  The authors of iperf2
 are (in alphabetical order): Jon Dugan, John Estabrook, Jim Ferbuson,

src/iperf.h

@@ -116,6 +116,7 @@ struct iperf_settings
     iperf_size_t bytes;             /* number of bytes to send */
     iperf_size_t blocks;            /* number of blocks (packets) to send */
     char      unit_format;          /* -f */
+    int       num_ostreams;         /* SCTP initmsg settings */
 };
 
 struct iperf_test;
@@ -186,6 +187,12 @@ struct iperf_textline {
     TAILQ_ENTRY(iperf_textline) textlineentries;
 };
 
+struct xbind_entry {
+    char *name;
+    struct addrinfo *ai;
+    TAILQ_ENTRY(xbind_entry) link;
+};
+
 struct iperf_test
 {
     char      role;                             /* 'c' lient or 's' erver */
@@ -194,7 +201,8 @@ struct iperf_test
     struct protocol *protocol;
     signed char state;
     char     *server_hostname;                  /* -c option */
-    char     *bind_address;                     /* -B option */
+    char     *bind_address;                     /* first -B option */
+    TAILQ_HEAD(xbind_addrhead, xbind_entry) xbind_addrs; /* all -X opts */
     int       bind_port;                        /* --cport option */
     int       server_port;
     int       omit;                             /* duration of omit period (-O flag) */

src/iperf3.1

@@ -130,10 +130,10 @@ run in reverse mode (server sends, client receives)
 window size / socket buffer size (this gets sent to the server and used on that side too)
 .TP
 .BR -M ", " --set-mss " \fIn\fR"
-set TCP maximum segment size (MTU - 40 bytes)
+set TCP/SCTP maximum segment size (MTU - 40 bytes)
 .TP
 .BR -N ", " --no-delay " "
-set TCP no delay, disabling Nagle's Algorithm
+set TCP/SCTP no delay, disabling Nagle's Algorithm
 .TP
 .BR -4 ", " --version4 " "
 only use IPv4
@@ -147,6 +147,24 @@ set the IP 'type of service'
 .BR -L ", " --flowlabel " \fIn\fR"
 set the IPv6 flow label (currently only supported on Linux)
 .TP
+.BR -X ", " --xbind " \fIname\fR"
+Bind SCTP associations to a specific subset of links using sctp_bindx(3).
+The \fB--B\fR flag will be ignored if this flag is specified.
+Normally SCTP will include the protocol addresses of all active links
+on the local host when setting up an association. Specifying at least
+one \fB--X\fR name will disable this behaviour.
+This flag must be specified for each link to be included in the
+association, and is supported for both iperf servers and clients
+(the latter are supported by passing the first \fB--X\fR argument to bind(2)).
+Hostnames are accepted as arguments and are resolved using
+getaddrinfo(3).
+If the \fB--4\fR or \fB--6\fR flags are specified, names
+which do not resolve to addresses within the
+specified protocol family will be ignored.
+.TP
+.BR --nstreams " \fIn\fR"
+Set number of SCTP streams.
+.TP
 .BR -Z ", " --zerocopy " "
 Use a "zero copy" method of sending data, such as sendfile(2),
 instead of the usual write(2).

src/iperf_api.c

@@ -636,6 +636,8 @@ iperf_parse_arguments(struct iperf_test *test, int argc, char **argv)
 #endif /* HAVE_TCP_CONGESTION */
 #if defined(HAVE_SCTP)
         {"sctp", no_argument, NULL, OPT_SCTP},
+        {"nstreams", required_argument, NULL, OPT_NUMSTREAMS},
+        {"xbind", required_argument, NULL, 'X'},
 #endif
 	{"pidfile", required_argument, NULL, 'I'},
 	{"logfile", required_argument, NULL, OPT_LOGFILE},
@@ -652,10 +654,11 @@ iperf_parse_arguments(struct iperf_test *test, int argc, char **argv)
     char* comma;
 #endif /* HAVE_CPU_AFFINITY */
     char* slash;
+    struct xbind_entry *xbe;
 
     blksize = 0;
     server_flag = client_flag = rate_flag = duration_flag = 0;
-    while ((flag = getopt_long(argc, argv, "p:f:i:D1VJvsc:ub:t:n:k:l:P:Rw:B:M:N46S:L:ZO:F:A:T:C:dI:h", longopts, NULL)) != -1) {
+    while ((flag = getopt_long(argc, argv, "p:f:i:D1VJvsc:ub:t:n:k:l:P:Rw:B:M:N46S:L:ZO:F:A:T:C:dI:hX:", longopts, NULL)) != -1) {
         switch (flag) {
             case 'p':
                 test->server_port = atoi(optarg);
@@ -719,6 +722,14 @@ iperf_parse_arguments(struct iperf_test *test, int argc, char **argv)
 #endif /* HAVE_SCTP */
             break;
 
+            case OPT_NUMSTREAMS:
+#if defined(linux) || defined(__FreeBSD__)
+                test->settings->num_ostreams = unit_atoi(optarg);
+                client_flag = 1;
+#else /* linux */
+                i_errno = IEUNIMP;
+                return -1;
+#endif /* linux */
             case 'b':
 		slash = strchr(optarg, '/');
 		if (slash) {
@@ -818,6 +829,20 @@ iperf_parse_arguments(struct iperf_test *test, int argc, char **argv)
                 return -1;
 #endif /* HAVE_FLOWLABEL */
                 break;
+            case 'X':
+		xbe = (struct xbind_entry *)malloc(sizeof(struct xbind_entry));
+                if (!xbe) {
+		    i_errno = IESETSCTPBINDX;
+                    return -1;
+                }
+	        memset(xbe, 0, sizeof(*xbe));
+                xbe->name = strdup(optarg);
+                if (!xbe->name) {
+		    i_errno = IESETSCTPBINDX;
+                    return -1;
+                }
+		TAILQ_INSERT_TAIL(&test->xbind_addrs, xbe, link);
+                break;
             case 'Z':
                 if (!has_sendfile()) {
                     i_errno = IENOSENDFILE;
@@ -1732,6 +1757,7 @@ iperf_defaults(struct iperf_test *testp)
     testp->diskfile_name = (char*) 0;
     testp->affinity = -1;
     testp->server_affinity = -1;
+    TAILQ_INIT(&testp->xbind_addrs);
 #if defined(HAVE_CPUSET_SETAFFINITY)
     CPU_ZERO(&testp->cpumask);
 #endif /* HAVE_CPUSET_SETAFFINITY */
@@ -1845,6 +1871,18 @@ iperf_free_test(struct iperf_test *test)
 	free(test->server_hostname);
     if (test->bind_address)
 	free(test->bind_address);
+    if (!TAILQ_EMPTY(&test->xbind_addrs)) {
+        struct xbind_entry *xbe;
+
+        while (!TAILQ_EMPTY(&test->xbind_addrs)) {
+            xbe = TAILQ_FIRST(&test->xbind_addrs);
+            TAILQ_REMOVE(&test->xbind_addrs, xbe, link);
+            if (xbe->ai)
+                freeaddrinfo(xbe->ai);
+            free(xbe->name);
+            free(xbe);
+        }
+    }
     free(test->settings);
     if (test->title)
 	free(test->title);
@@ -1885,6 +1923,18 @@ iperf_free_test(struct iperf_test *test)
 	free(t);
     }
 
+    /* sctp_bindx: do not free the arguments, only the resolver results */
+    if (!TAILQ_EMPTY(&test->xbind_addrs)) {
+        struct xbind_entry *xbe;
+
+        TAILQ_FOREACH(xbe, &test->xbind_addrs, link) {
+            if (xbe->ai) {
+                freeaddrinfo(xbe->ai);
+                xbe->ai = NULL;
+            }
+        }
+    }
+
     /* XXX: Why are we setting these values to NULL? */
     // test->streams = NULL;
     test->stats_callback = NULL;

src/iperf_api.h

@@ -48,6 +48,7 @@ struct iperf_stream;
 #define OPT_GET_SERVER_OUTPUT 3
 #define OPT_UDP_COUNTERS_64BIT 4
 #define OPT_CLIENT_PORT 5
+#define OPT_NUMSTREAMS 6
 
 /* states */
 #define TEST_START 1
@@ -308,8 +309,8 @@ enum {
     IECLIENTTERM = 119,     // The client has terminated
     IESERVERTERM = 120,     // The server has terminated
     IEACCESSDENIED = 121,   // The server is busy running a test. Try again later.
-    IESETNODELAY = 122,     // Unable to set TCP NODELAY (check perror)
-    IESETMSS = 123,         // Unable to set TCP MSS (check perror)
+    IESETNODELAY = 122,     // Unable to set TCP/SCTP NODELAY (check perror)
+    IESETMSS = 123,         // Unable to set TCP/SCTP MSS (check perror)
     IESETBUF = 124,         // Unable to set socket buffer size (check perror)
     IESETTOS = 125,         // Unable to set IP TOS (check perror)
     IESETCOS = 126,         // Unable to set IPv6 traffic class (check perror)
@@ -324,6 +325,8 @@ enum {
     IEPIDFILE = 135,	    // Unable to write PID file
     IEV6ONLY = 136,  	    // Unable to set/unset IPV6_V6ONLY (check perror)
     IESETSCTPDISABLEFRAG = 137, // Unable to set SCTP Fragmentation (check perror)
+    IESETSCTPNSTREAM= 138,  //  Unable to set SCTP number of streams (check perror)
+    IESETSCTPBINDX= 139,    // Unable to process sctp_bindx() parameters
     /* 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

@@ -241,11 +241,11 @@ iperf_strerror(int i_errno)
             snprintf(errstr, len, "the server is busy running a test. try again later");
             break;
         case IESETNODELAY:
-            snprintf(errstr, len, "unable to set TCP NODELAY");
+            snprintf(errstr, len, "unable to set TCP/SCTP NODELAY");
             perr = 1;
             break;
         case IESETMSS:
-            snprintf(errstr, len, "unable to set TCP MSS");
+            snprintf(errstr, len, "unable to set TCP/SCTP MSS");
             perr = 1;
             break;
         case IESETBUF:
@@ -347,6 +347,10 @@ iperf_strerror(int i_errno)
             snprintf(errstr, len, "unable to set SCTP_DISABLE_FRAGMENTS");
             perr = 1;
             break;
+        case IESETSCTPNSTREAM:
+            snprintf(errstr, len, "unable to set SCTP_INIT num of SCTP streams\n");
+            perr = 1;
+            break;
     }
 
     if (herr || perr)

src/iperf_locale.c

@@ -120,6 +120,8 @@ const char usage_longstr[] = "Usage: iperf [-s|-c host] [options]\n"
                            "  -c, --client    <host>    run in client mode, connecting to <host>\n"
 #if defined(HAVE_SCTP)
                            "  --sctp                    use SCTP rather than TCP\n"
+                           "  -X, --xbind <name>        bind SCTP association to links\n"
+                           "  --nstreams      #         number of SCTP streams\n"
 #endif /* HAVE_SCTP */
                            "  -u, --udp                 use UDP rather than TCP\n"
                            "  -b, --bandwidth #[KMG][/#] target bandwidth in bits/sec (0 for unlimited)\n"
@@ -137,8 +139,8 @@ const char usage_longstr[] = "Usage: iperf [-s|-c host] [options]\n"
 #if defined(HAVE_TCP_CONGESTION)
                            "  -C, --congestion <algo>   set TCP congestion control algorithm (Linux and FreeBSD only)\n"
 #endif /* HAVE_TCP_CONGESTION */
-                           "  -M, --set-mss   #         set TCP maximum segment size (MTU - 40 bytes)\n"
-                           "  -N, --nodelay             set TCP no delay, disabling Nagle's Algorithm\n"
+                           "  -M, --set-mss   #         set TCP/SCTP maximum segment size (MTU - 40 bytes)\n"
+                           "  -N, --no-delay            set TCP/SCTP no delay, disabling Nagle's Algorithm\n"
                            "  -4, --version4            only use IPv4\n"
                            "  -6, --version6            only use IPv6\n"
                            "  -S, --tos N               set the IP 'type of service'\n"