ndp: reintroduce address replay
[project/odhcpd.git] / src / odhcpd.c
index b8651dd..5774a4f 100644 (file)
@@ -49,6 +49,12 @@ static int rtnl_seq = 0;
 static int urandom_fd = -1;
 
 
+static void sighandler(_unused int signal)
+{
+       uloop_end();
+}
+
+
 int main()
 {
        openlog("odhcpd", LOG_PERROR | LOG_PID, LOG_DAEMON);
@@ -71,6 +77,8 @@ int main()
                return 4;
 
        signal(SIGUSR1, SIG_IGN);
+       signal(SIGINT, sighandler);
+       signal(SIGTERM, sighandler);
 
        if (init_router())
                return 4;
@@ -105,11 +113,11 @@ int odhcpd_open_rtnl(void)
 
 
 // Read IPv6 MTU for interface
-int odhcpd_get_interface_mtu(const char *ifname)
+int odhcpd_get_interface_config(const char *ifname, const char *what)
 {
        char buf[64];
-       const char *sysctl_pattern = "/proc/sys/net/ipv6/conf/%s/mtu";
-       snprintf(buf, sizeof(buf), sysctl_pattern, ifname);
+       const char *sysctl_pattern = "/proc/sys/net/ipv6/conf/%s/%s";
+       snprintf(buf, sizeof(buf), sysctl_pattern, ifname, what);
 
        int fd = open(buf, O_RDONLY);
        ssize_t len = read(fd, buf, sizeof(buf) - 1);
@@ -118,10 +126,8 @@ int odhcpd_get_interface_mtu(const char *ifname)
        if (len < 0)
                return -1;
 
-
        buf[len] = 0;
        return atoi(buf);
-
 }
 
 
@@ -145,8 +151,15 @@ ssize_t odhcpd_send(int socket, struct sockaddr_in6 *dest,
 {
        // Construct headers
        uint8_t cmsg_buf[CMSG_SPACE(sizeof(struct in6_pktinfo))] = {0};
-       struct msghdr msg = {(void*)dest, sizeof(*dest), iov, iov_len,
-                               cmsg_buf, sizeof(cmsg_buf), 0};
+       struct msghdr msg = {
+               .msg_name = (void *) dest,
+               .msg_namelen = sizeof(*dest),
+               .msg_iov = iov,
+               .msg_iovlen = iov_len,
+               .msg_control = cmsg_buf,
+               .msg_controllen = sizeof(cmsg_buf),
+               .msg_flags = 0
+       };
 
        // Set control data (define destination interface)
        struct cmsghdr *chdr = CMSG_FIRSTHDR(&msg);
@@ -161,12 +174,6 @@ ssize_t odhcpd_send(int socket, struct sockaddr_in6 *dest,
                        || IN6_IS_ADDR_MC_LINKLOCAL(&dest->sin6_addr))
                dest->sin6_scope_id = iface->ifindex;
 
-       // IPV6_PKTINFO doesn't really work for IPv6-raw sockets (bug?)
-       if (dest->sin6_port == 0) {
-               msg.msg_control = NULL;
-               msg.msg_controllen = 0;
-       }
-
        char ipbuf[INET6_ADDRSTRLEN];
        inet_ntop(AF_INET6, &dest->sin6_addr, ipbuf, sizeof(ipbuf));
 
@@ -241,20 +248,81 @@ ssize_t odhcpd_get_interface_addresses(int ifindex,
                if (ifa->ifa_flags & IFA_F_DEPRECATED)
                        addrs[ret].preferred = 0;
 
-               addrs[ret].has_class = false;
-               addrs[ret].class = 0;
-#ifdef WITH_UBUS
-               struct interface *iface = odhcpd_get_interface_by_index(ifindex);
-               if (iface)
-                       addrs[ret].has_class = ubus_get_class(iface->ifname,
-                                       &addrs[ret].addr, &addrs[ret].class);
-#endif
                ++ret;
        }
 
        return ret;
 }
 
+int odhcpd_get_preferred_interface_address(int ifindex, struct in6_addr *addr)
+{
+       struct odhcpd_ipaddr ipaddrs[8];
+       ssize_t ip_cnt = odhcpd_get_interface_addresses(ifindex, ipaddrs, ARRAY_SIZE(ipaddrs));
+       uint32_t preferred = 0;
+       int ret = 0;
+
+       for (ssize_t i = 0; i < ip_cnt; i++) {
+               struct odhcpd_ipaddr *ipaddr = &ipaddrs[i];
+
+               if (ipaddr->preferred > preferred || !preferred) {
+                       preferred = ipaddr->preferred;
+                       *addr = ipaddr->addr;
+                       ret = 1;
+               }
+       }
+
+       return ret;
+}
+
+void odhcpd_setup_route(const struct in6_addr *addr, int prefixlen,
+               const struct interface *iface, const struct in6_addr *gw,
+               int metric, bool add)
+{
+       struct req {
+               struct nlmsghdr nh;
+               struct rtmsg rtm;
+               struct rtattr rta_dst;
+               struct in6_addr dst_addr;
+               struct rtattr rta_oif;
+               uint32_t ifindex;
+               struct rtattr rta_table;
+               uint32_t table;
+               struct rtattr rta_prio;
+               uint32_t prio;
+               struct rtattr rta_gw;
+               struct in6_addr gw;
+       } req = {
+               {sizeof(req), 0, NLM_F_REQUEST, ++rtnl_seq, 0},
+               {AF_INET6, prefixlen, 0, 0, 0, 0, 0, 0, 0},
+               {sizeof(struct rtattr) + sizeof(struct in6_addr), RTA_DST},
+               *addr,
+               {sizeof(struct rtattr) + sizeof(uint32_t), RTA_OIF},
+               iface->ifindex,
+               {sizeof(struct rtattr) + sizeof(uint32_t), RTA_TABLE},
+               RT_TABLE_MAIN,
+               {sizeof(struct rtattr) + sizeof(uint32_t), RTA_PRIORITY},
+               metric,
+               {sizeof(struct rtattr) + sizeof(struct in6_addr), RTA_GATEWAY},
+               IN6ADDR_ANY_INIT,
+       };
+
+       if (gw)
+               req.gw = *gw;
+
+       if (add) {
+               req.nh.nlmsg_type = RTM_NEWROUTE;
+               req.nh.nlmsg_flags |= (NLM_F_CREATE | NLM_F_REPLACE);
+               req.rtm.rtm_protocol = RTPROT_STATIC;
+               req.rtm.rtm_scope = (gw) ? RT_SCOPE_UNIVERSE : RT_SCOPE_LINK;
+               req.rtm.rtm_type = RTN_UNICAST;
+       } else {
+               req.nh.nlmsg_type = RTM_DELROUTE;
+               req.rtm.rtm_scope = RT_SCOPE_NOWHERE;
+       }
+
+       req.nh.nlmsg_len = (gw) ? sizeof(req) : offsetof(struct req, rta_gw);
+       send(rtnl_socket, &req, req.nh.nlmsg_len, MSG_DONTWAIT);
+}
 
 struct interface* odhcpd_get_interface_by_index(int ifindex)
 {
@@ -304,8 +372,15 @@ static void odhcpd_receive_packets(struct uloop_fd *u, _unused unsigned int even
 
        while (true) {
                struct iovec iov = {data_buf, sizeof(data_buf)};
-               struct msghdr msg = {&addr, sizeof(addr), &iov, 1,
-                               cmsg_buf, sizeof(cmsg_buf), 0};
+               struct msghdr msg = {
+                       .msg_name = (void *) &addr,
+                       .msg_namelen = sizeof(addr),
+                       .msg_iov = &iov,
+                       .msg_iovlen = 1,
+                       .msg_control = cmsg_buf,
+                       .msg_controllen = sizeof(cmsg_buf),
+                       .msg_flags = 0
+               };
 
                ssize_t len = recvmsg(u->fd, &msg, MSG_DONTWAIT);
                if (len < 0) {
@@ -377,9 +452,14 @@ int odhcpd_register(struct odhcpd_event *event)
        return uloop_fd_add(&event->uloop, ULOOP_READ);
 }
 
-void odhcpd_urandom(void *data, size_t len)
+void odhcpd_process(struct odhcpd_event *event)
+{
+       odhcpd_receive_packets(&event->uloop, 0);
+}
+
+int odhcpd_urandom(void *data, size_t len)
 {
-       read(urandom_fd, data, len);
+       return read(urandom_fd, data, len);
 }