add ipv6 support

Signed-off-by: John Crispin <blogic@openwrt.org>

diff --git a/dns.h b/dns.h
index ba34a8589bc2f57d1f68c2fd73dc1ceaa7df98c0..a238db4b228be0524a998f998cf399dac423e616 100644 (file)
--- a/dns.h
+++ b/dns.h
@@ -29,6 +29,7 @@
 #define IS_COMPRESSED(x)       ((x & 0xc0) == 0xc0)
 
 #define MCAST_ADDR             "224.0.0.251"
+#define MCAST_ADDR6            "ff02::fb"
 #define MCAST_PORT             5353
 
 #define CLASS_FLUSH            0x8000

diff --git a/interface.c b/interface.c
index 2ed1d05cff5e9955b6d19778b835fc2d3663373e..8df85bd388269838669ec6fe815ab92e8c0a301a 100644 (file)
--- a/interface.c
+++ b/interface.c
@@ -12,12 +12,14 @@
  * GNU General Public License for more details.
  */
 
+#define _GNU_SOURCE
 #include <sys/socket.h>
 #include <sys/ioctl.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/utsname.h>
 #include <net/if.h>
+#include <netinet/in.h>
 #include <arpa/inet.h>
 
 #include <stdlib.h>
@@ -35,8 +37,8 @@
 #include "dns.h"
 #include "announce.h"
 
-int
-interface_send_packet(struct interface *iface, struct iovec *iov, int iov_len)
+static int
+interface_send_packet4(struct interface *iface, struct iovec *iov, int iov_len)
 {
        static size_t cmsg_data[( CMSG_SPACE(sizeof(struct in_pktinfo)) / sizeof(size_t)) + 1];
        static struct sockaddr_in a;
@@ -69,6 +71,49 @@ interface_send_packet(struct interface *iface, struct iovec *iov, int iov_len)
        return sendmsg(fd, &m, 0);
 }
 
+static int
+interface_send_packet6(struct interface *iface, struct iovec *iov, int iov_len)
+{
+       static size_t cmsg_data[( CMSG_SPACE(sizeof(struct in6_pktinfo)) / sizeof(size_t)) + 1];
+       static struct sockaddr_in6 a;
+       static struct msghdr m = {
+               .msg_name = (struct sockaddr *) &a,
+               .msg_namelen = sizeof(a),
+               .msg_control = cmsg_data,
+               .msg_controllen = CMSG_LEN(sizeof(struct in6_pktinfo)),
+       };
+       struct in6_pktinfo *pkti;
+       struct cmsghdr *cmsg;
+       int fd = iface->fd.fd;
+
+       a.sin6_family = AF_INET6;
+       a.sin6_port = htons(MCAST_PORT);
+       m.msg_iov = iov;
+       m.msg_iovlen = iov_len;
+
+       memset(cmsg_data, 0, sizeof(cmsg_data));
+       cmsg = CMSG_FIRSTHDR(&m);
+       cmsg->cmsg_len = m.msg_controllen;
+       cmsg->cmsg_level = IPPROTO_IPV6;
+       cmsg->cmsg_type = IPV6_PKTINFO;
+
+       pkti = (struct in6_pktinfo*) CMSG_DATA(cmsg);
+       pkti->ipi6_ifindex = iface->ifindex;
+
+       inet_pton(AF_INET6, MCAST_ADDR6, &a.sin6_addr);
+
+       return sendmsg(fd, &m, 0);
+}
+
+int
+interface_send_packet(struct interface *iface, struct iovec *iov, int iov_len)
+{
+       if (iface->v6)
+               return interface_send_packet6(iface, iov, iov_len);
+
+       return interface_send_packet4(iface, iov, iov_len);
+}
+
 static void interface_close(struct interface *iface)
 {
        if (iface->fd.fd < 0)
@@ -101,7 +146,8 @@ read_socket(struct uloop_fd *u, unsigned int events)
 
        len = read(u->fd, buffer, sizeof(buffer));
        if (len < 1) {
-               fprintf(stderr, "read failed: %s\n", strerror(errno));
+               if (errno != EAGAIN)
+                       fprintf(stderr, "read failed: %s\n", strerror(errno));
                return;
        }
 
@@ -109,7 +155,7 @@ read_socket(struct uloop_fd *u, unsigned int events)
 }
 
 static int
-interface_socket_setup(struct interface *iface)
+interface_socket_setup4(struct interface *iface)
 {
        struct ip_mreqn mreq;
        uint8_t ttl = 255;
@@ -159,18 +205,80 @@ interface_socket_setup(struct interface *iface)
        return 0;
 }
 
+static int
+interface_socket_setup6(struct interface *iface)
+{
+       struct ipv6_mreq mreq;
+       int ttl = 255;
+       int yes = 1;
+       int no = 0;
+       struct sockaddr_in6 sa = { 0 };
+       int fd = iface->fd.fd;
+
+       sa.sin6_family = AF_INET6;
+       sa.sin6_port = htons(MCAST_PORT);
+       inet_pton(AF_INET6, MCAST_ADDR6, &sa.sin6_addr);
+
+       memset(&mreq, 0, sizeof(mreq));
+       mreq.ipv6mr_multiaddr = sa.sin6_addr;
+       mreq.ipv6mr_interface = iface->ifindex;
+
+       if (setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl)) < 0)
+               fprintf(stderr, "ioctl failed: IPV6_MULTICAST_HOPS\n");
+
+       if (setsockopt(fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &ttl, sizeof(ttl)) < 0)
+               fprintf(stderr, "ioctl failed: IPV6_UNICAST_HOPS\n");
+
+       if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) < 0)
+               fprintf(stderr, "ioctl failed: SO_REUSEADDR\n");
+
+       setsockopt(fd, IPPROTO_IPV6, IPV6_LEAVE_GROUP, &mreq, sizeof(mreq));
+       if (setsockopt(fd, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq, sizeof(mreq)) < 0) {
+               fprintf(stderr, "failed to join multicast group: %s\n", strerror(errno));
+               close(fd);
+               fd = -1;
+               return -1;
+       }
+
+       if (setsockopt(fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &yes, sizeof(yes)) < 0)
+               fprintf(stderr, "ioctl failed: IPV6_RECVPKTINFO\n");
+
+       if (setsockopt(fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &yes, sizeof(yes)) < 0)
+               fprintf(stderr, "ioctl failed: IPV6_RECVHOPLIMIT\n");
+
+       if (setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &no, sizeof(no)) < 0)
+               fprintf(stderr, "ioctl failed: IPV6_MULTICAST_LOOP\n");
+
+       return 0;
+}
+
 static void
 reconnect_socket(struct uloop_timeout *timeout)
 {
        struct interface *iface = container_of(timeout, struct interface, reconnect);
+       char mcast_addr[16];
+       int type = 0;
+
+       if (iface->v6) {
+               snprintf(mcast_addr, sizeof(mcast_addr), "%s%%%s", iface->mcast_addr, iface->name);
+               type = USOCK_IPV6ONLY;
+       } else {
+               snprintf(mcast_addr, sizeof(mcast_addr), "%s", iface->mcast_addr);
+               type = USOCK_IPV4ONLY;
+       }
 
-       iface->fd.fd = usock(USOCK_UDP | USOCK_SERVER | USOCK_NONBLOCK, MCAST_ADDR, "5353");
+       iface->fd.fd = usock(USOCK_UDP | USOCK_SERVER | USOCK_NONBLOCK | type, mcast_addr, "5353");
        if (iface->fd.fd < 0) {
-               fprintf(stderr, "failed to add listener: %s\n", strerror(errno));
+               fprintf(stderr, "failed to add listener %s: %s\n", mcast_addr, strerror(errno));
                goto retry;
        }
 
-       if (interface_socket_setup(iface)) {
+       if (!iface->v6 && interface_socket_setup4(iface)) {
+               iface->fd.fd = -1;
+               goto retry;
+       }
+
+       if (iface->v6 && interface_socket_setup6(iface)) {
                iface->fd.fd = -1;
                goto retry;
        }
@@ -229,31 +337,61 @@ get_iface_ipv4(struct interface *iface)
 
        sin = (struct sockaddr_in *) &ir.ifr_addr;
        memcpy(&iface->v4_addr, &sin->sin_addr, sizeof(iface->v4_addr));
-
+       iface->mcast_addr = MCAST_ADDR;
 out:
        close(sock);
        return ret;
 }
 
-int interface_add(const char *name)
+static int
+get_iface_ipv6(struct interface *iface)
+{
+       struct sockaddr_in6 addr = {AF_INET6, 0, iface->ifindex, IN6ADDR_ANY_INIT, 0};
+       socklen_t alen = sizeof(addr);
+       int sock, ret = -1;
+
+       addr.sin6_addr.s6_addr[0] = 0xff;
+       addr.sin6_addr.s6_addr[1] = 0x02;
+       addr.sin6_addr.s6_addr[15] = 0x01;
+
+       sock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
+       connect(sock, (struct sockaddr*)&addr, sizeof(addr));
+       ret = getsockname(sock, (struct sockaddr*)&addr, &alen);
+       if (!ret) {
+               memcpy(&iface->v6_addr, &addr.sin6_addr, sizeof(iface->v6_addr));
+               iface->mcast_addr = MCAST_ADDR6;
+               iface->v6 = 1;
+       }
+       close(sock);
+       return ret;
+}
+
+static int _interface_add(const char *name, int v6)
 {
        struct interface *iface;
        char *name_buf;
+       char *id_buf;
 
        iface = calloc_a(sizeof(*iface),
-               &name_buf, strlen(name) + 1);
+               &name_buf, strlen(name) + 1,
+               &id_buf, strlen(name) + 3);
 
+       sprintf(id_buf, "%d_%s", v6, name);
        iface->name = strcpy(name_buf, name);
+       iface->id = id_buf;
        iface->ifindex = if_nametoindex(name);
        iface->fd.fd = -1;
 
        if (iface->ifindex <= 0)
                goto error;
 
-       if (get_iface_ipv4(iface))
+       if (!v6 && get_iface_ipv4(iface))
+               goto error;
+
+       if (v6 && get_iface_ipv6(iface))
                goto error;
 
-       vlist_add(&interfaces, &iface->node, name);
+       vlist_add(&interfaces, &iface->node, iface->id);
        return 0;
 
 error:
@@ -261,4 +399,11 @@ error:
        return -1;
 }
 
+int interface_add(const char *name)
+{
+       int v4 = _interface_add(name, 0);
+       int v6 = _interface_add(name, 1);
+       return v4 && v6;
+}
+
 VLIST_TREE(interfaces, avl_strcmp, iface_update_cb, false, false);

diff --git a/interface.h b/interface.h
index 8fffc7e1ebae38a7b2ccc23ce085df4757f810fc..fcbc3e68cdfc5a3d66e9a77a7ccf9a7a43921f94 100644 (file)
--- a/interface.h
+++ b/interface.h
@@ -29,14 +29,19 @@ struct interface {
        struct vlist_node node;
 
        const char *name;
+       char *id;
        struct uloop_fd fd;
        struct uloop_timeout reconnect;
 
+       int v6;
        int ifindex;
        struct in_addr v4_addr;
+       struct in6_addr v6_addr;
 
        struct uloop_timeout announce_timer;
        int announce_state;
+
+       char *mcast_addr;
 };
 
 int interface_add(const char *name);