dhcpv4: Keep DHCPv4 assignment lifetime value in sync with assigned leasetime
[project/odhcpd.git] / src / odhcpd.c
index 52bca13..6f034bf 100644 (file)
@@ -113,11 +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);
@@ -126,10 +126,8 @@ int odhcpd_get_interface_mtu(const char *ifname)
        if (len < 0)
                return -1;
 
-
        buf[len] = 0;
        return atoi(buf);
-
 }
 
 
@@ -176,12 +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));
 
@@ -262,24 +254,71 @@ ssize_t odhcpd_get_interface_addresses(int ifindex,
        return ret;
 }
 
-int odhcpd_get_preferred_interface_address(int ifindex, struct in6_addr *addr)
+int odhcpd_get_linklocal_interface_address(int ifindex, struct in6_addr *lladdr)
 {
-       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;
+               int status = -1;
+               struct sockaddr_in6 addr = {AF_INET6, 0, 0, ALL_IPV6_ROUTERS, ifindex};
+               socklen_t alen = sizeof(addr);
+               int sock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
+
+               if (!connect(sock, (struct sockaddr*)&addr, sizeof(addr)) &&
+                               !getsockname(sock, (struct sockaddr*)&addr, &alen)) {
+                       *lladdr = addr.sin6_addr;
+                       status = 0;
                }
+
+               close(sock);
+               return status;
+}
+
+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;
        }
 
-       return ret;
+       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)
@@ -328,6 +367,15 @@ static void odhcpd_receive_packets(struct uloop_fd *u, _unused unsigned int even
                struct sockaddr_nl nl;
        } addr;
 
+       if (u->error) {
+               int ret = -1;
+               socklen_t ret_len = sizeof(ret);
+               getsockopt(u->fd, SOL_SOCKET, SO_ERROR, &ret, &ret_len);
+               u->error = false;
+               if (e->handle_error)
+                       e->handle_error(ret);
+       }
+
        while (true) {
                struct iovec iov = {data_buf, sizeof(data_buf)};
                struct msghdr msg = {
@@ -395,7 +443,6 @@ static void odhcpd_receive_packets(struct uloop_fd *u, _unused unsigned int even
                else if (addr.in.sin_family == AF_INET)
                        inet_ntop(AF_INET, &addr.in.sin_addr, ipbuf, sizeof(ipbuf));
 
-               syslog(LOG_DEBUG, "--");
                syslog(LOG_DEBUG, "Received %li Bytes from %s%%%s", (long)len,
                                ipbuf, (iface) ? iface->ifname : "netlink");
 
@@ -407,7 +454,8 @@ static void odhcpd_receive_packets(struct uloop_fd *u, _unused unsigned int even
 int odhcpd_register(struct odhcpd_event *event)
 {
        event->uloop.cb = odhcpd_receive_packets;
-       return uloop_fd_add(&event->uloop, ULOOP_READ);
+       return uloop_fd_add(&event->uloop, ULOOP_READ |
+                       ((event->handle_error) ? ULOOP_ERROR_CB : 0));
 }
 
 void odhcpd_process(struct odhcpd_event *event)