--- /dev/null
+/*
+ * "Copyright (c) 2008, 2009 The Regents of the University of California.
+ * All rights reserved."
+ *
+ * Permission to use, copy, modify, and distribute this software and its
+ * documentation for any purpose, without fee, and without written agreement is
+ * hereby granted, provided that the above copyright notice, the following
+ * two paragraphs and the author appear in all copies of this software.
+ *
+ * IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT
+ * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF
+ * CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS."
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+
+#include <net/if.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <arpa/inet.h>
+
+#include "mcast.h"
+#include "logging.h"
+
+int __mcast_sock;
+struct sockaddr_in6 __mcast_addr;
+char __mcast_dev[IFNAMSIZ];
+
+static int open_loopback(struct sockaddr_in6 *laddr) {
+
+ /* we need to send to the loopback address, not the group */
+ memcpy(&__mcast_addr.sin6_addr, &in6addr_loopback, sizeof(struct in6_addr));
+ memcpy(&laddr->sin6_addr, &in6addr_loopback, sizeof(struct in6_addr));
+
+ /* bind to the local address (we're already BINDTODEVICE, so this
+ might be redundant) */
+ if (bind(__mcast_sock, (struct sockaddr *)laddr, sizeof(struct sockaddr_in6)) < 0) {
+ log_fatal_perror("binding multicast socket failed");
+ goto fail;
+ }
+
+ return __mcast_sock;
+ fail:
+ close(__mcast_sock);
+ return -1;
+}
+
+int mcast_start(char *dev) {
+ struct ipv6_mreq join;
+ struct ifreq ifr;
+ int opt;
+ int ifindex = if_nametoindex(dev);
+
+ __mcast_addr.sin6_family = AF_INET6;
+ inet_pton(AF_INET6, "ff12::cafe:babe", &__mcast_addr.sin6_addr);
+ __mcast_addr.sin6_port = htons(10023);
+ __mcast_addr.sin6_scope_id = ifindex;
+
+ strncpy(__mcast_dev, dev, IFNAMSIZ);
+
+ struct sockaddr_in6 laddr = {
+ .sin6_family = AF_INET6,
+ .sin6_port = __mcast_addr.sin6_port,
+ .sin6_addr = IN6ADDR_ANY_INIT,
+ .sin6_scope_id = ifindex,
+ };
+
+
+ /* get the socket */
+ if ((__mcast_sock = socket(PF_INET6, SOCK_DGRAM, 0)) < 0) {
+ log_fatal_perror("error opening socket");
+ return -1;
+ }
+
+ /* bind it to the device we're going to join the link-local
+ multicast group on */
+ memset(&ifr, 0, sizeof(struct ifreq));
+ strncpy(ifr.ifr_name, dev, IFNAMSIZ);
+ if (setsockopt(__mcast_sock, SOL_SOCKET, SO_BINDTODEVICE,
+ (char *)&ifr, sizeof(struct ifreq)) < 0) {
+ log_fatal_perror("could not BINDTODEVICE");
+ goto fail;
+ }
+
+ /* the loopback on linux doesn't support multicast. that's okay,
+ though, since we can just attach to it and use it to feed routing
+ reports back into us. */
+ if (strncmp(dev, "lo", 2) == 0) {
+ return open_loopback(&laddr);
+ }
+
+ /* receive messages we send */
+ opt = 1;
+ if (setsockopt(__mcast_sock, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &opt, sizeof(opt)) < 0) {
+ log_fatal_perror("setting loop failed");
+ goto fail;
+ }
+
+ opt = 1;
+ if (setsockopt(__mcast_sock, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt)) < 0) {
+ log_fatal_perror("setting reuse failed");
+ goto fail;
+ }
+
+ /* bind to the local address (we're already BINDTODEVICE, so this
+ might be redundant) */
+ if (bind(__mcast_sock, (struct sockaddr *)&laddr, sizeof(struct sockaddr_in6)) < 0) {
+ log_fatal_perror("binding multicast socket failed");
+ goto fail;
+ }
+
+ memset(&join, 0, sizeof(struct ipv6_mreq));
+ memcpy(&join.ipv6mr_multiaddr, &__mcast_addr.sin6_addr, sizeof(struct in6_addr));
+ join.ipv6mr_interface = ifindex;
+
+ if (setsockopt(__mcast_sock, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &join, sizeof(join)) < 0) {
+ log_fatal_perror("error joining group");
+ goto fail;
+ }
+
+ return __mcast_sock;
+ fail:
+ close(__mcast_sock);
+ return -1;
+}
+
+
+
+int mcast_recvfrom(struct sockaddr_in6 *from, void *buf, int len) {
+ int rc;
+ socklen_t fromlen = sizeof(struct sockaddr_in6);
+
+ if ((rc = recvfrom(__mcast_sock, buf, len, 0, (struct sockaddr *)from, &fromlen)) < 0) {
+ log_fatal_perror("multicast receive");
+ return -1;
+ }
+ return rc;
+}
+
+int mcast_send(void *data, int len) {
+ int rc;
+
+ if ((rc = sendto(__mcast_sock, data, len, 0, (struct sockaddr *)&__mcast_addr, sizeof(struct sockaddr_in6))) < 0) {
+ log_fatal_perror("send failed");
+ return -1;
+ }
+ return 0;
+}
+
+#if 0
+int main(int argc, char **argv) {
+
+ char *dev = argv[1];
+ int fd;
+ struct sockaddr_in6 grp = {
+ .sin6_port = htons(10620),
+ };
+
+ if (argc < 2) {
+ printf("\n\t%s <iface>\n\n", argv[0]);
+ exit(1);
+ }
+
+ inet_pton(AF_INET6, "ff12::1abc", &grp.sin6_addr);
+
+ fd = mcast_start(&grp, dev);
+ printf("mcast start done: %i\n", fd);
+
+ struct sockaddr_in6 from;
+ char rxbuf[1024];
+ int len;
+
+ if (argc == 3 && strcmp(argv[2], "listen") == 0) {
+
+ printf("listening\n");
+
+ while (1) {
+ len = mcast_recvfrom(&from, rxbuf, 1024);
+ if (len > 0) {
+ rxbuf[len] = '\0';
+ puts(rxbuf);
+ }
+ }
+ } else {
+ char *msg = "hello, mcast world!";
+ while (1) {
+ mcast_send(msg, strlen(msg)+1);
+ sleep(1);
+ len = mcast_recvfrom(&from, rxbuf, 1024);
+ if (len > 0) {
+ rxbuf[len] = '\0';
+ puts(rxbuf);
+ }
+
+ }
+ }
+}
+#endif
projects / tinyos-2.x.git / blobdiff