diff --git a/ndhc/ifset.c b/ndhc/ifset.c index 5b6fe84..5562c9f 100644 --- a/ndhc/ifset.c +++ b/ndhc/ifset.c @@ -241,6 +241,58 @@ static ssize_t rtnl_addr_broadcast_send(int fd, int type, int ifa_flags, return rtnl_do_send(fd, request, header->nlmsg_len, __func__); } +static ssize_t rtnl_set_default_gw_v4(int fd, uint32_t gw4, int metric) +{ + uint8_t request[NLMSG_ALIGN(sizeof(struct nlmsghdr)) + + NLMSG_ALIGN(sizeof(struct ifinfomsg)) + + RTA_LENGTH(sizeof(uint32_t))]; + struct nlmsghdr *header; + struct rtmsg *rtmsg; + + memset(&request, 0, sizeof request); + header = (struct nlmsghdr *)request; + header->nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg)); + header->nlmsg_type = RTM_NEWROUTE; + header->nlmsg_flags = NLM_F_REPLACE | NLM_F_ACK | NLM_F_REQUEST; + header->nlmsg_seq = ifset_nl_seq++; + + rtmsg = NLMSG_DATA(header); + rtmsg->rtm_family = AF_INET; + rtmsg->rtm_table = RT_TABLE_DEFAULT; + rtmsg->rtm_protocol = RTPROT_STATIC; + rtmsg->rtm_scope = RT_SCOPE_UNIVERSE; + rtmsg->rtm_type = RTN_UNICAST; + + uint32_t dstaddr4 = 0; + if (nl_add_rtattr(header, sizeof request, RTA_DST, + &dstaddr4, sizeof dstaddr4) < 0) { + log_line("%s: (%s) couldn't add RTA_DST to nlmsg", + client_config.interface, __func__); + return -1; + } + if (nl_add_rtattr(header, sizeof request, RTA_OIF, + &client_config.ifindex, + sizeof client_config.ifindex) < 0) { + log_line("%s: (%s) couldn't add RTA_OIF to nlmsg", + client_config.interface, __func__); + return -1; + } + if (nl_add_rtattr(header, sizeof request, RTA_GATEWAY, + &gw4, sizeof gw4) < 0) { + log_line("%s: (%s) couldn't add RTA_GATEWAY to nlmsg", + client_config.interface, __func__); + return -1; + } + if (nl_add_rtattr(header, sizeof request, RTA_METRICS, + &metric, sizeof metric) < 0) { + log_line("%s: (%s) couldn't add RTA_METRICS to nlmsg", + client_config.interface, __func__); + return -1; + } + + return rtnl_do_send(fd, request, header->nlmsg_len, __func__); +} + struct link_flag_data { int fd; uint32_t flags; @@ -478,50 +530,33 @@ void perform_ip_subnet_bcast(const char *str_ipaddr, } -void perform_router(const char *str, size_t len) +void perform_router(const char *str_router, size_t len) { - struct rtentry rt; - struct sockaddr_in *dest; - struct sockaddr_in *gateway; - struct sockaddr_in *mask; + if (!str_router) + return; + if (len < 7) + return; struct in_addr router; - int fd; - - if (!str) - return; - if (len < 4) - return; - if (inet_pton(AF_INET, str, &router) <= 0) - return; - - memset(&rt, 0, sizeof(struct rtentry)); - dest = (struct sockaddr_in *) &rt.rt_dst; - dest->sin_family = AF_INET; - dest->sin_addr.s_addr = 0x00000000; - gateway = (struct sockaddr_in *) &rt.rt_gateway; - gateway->sin_family = AF_INET; - gateway->sin_addr = router; - mask = (struct sockaddr_in *) &rt.rt_genmask; - mask->sin_family = AF_INET; - mask->sin_addr.s_addr = 0x00000000; - - rt.rt_flags = RTF_UP | RTF_GATEWAY; - if (mask->sin_addr.s_addr == 0xffffffff) rt.rt_flags |= RTF_HOST; - rt.rt_dev = client_config.interface; - rt.rt_metric = 1; - - fd = socket(AF_INET, SOCK_DGRAM, 0); - if (fd == -1) { - log_line("%s: (perform_router) failed to open interface socket: %s", - client_config.interface, strerror(errno)); + if (inet_pton(AF_INET, str_router, &router) <= 0) { + log_line("%s: (%s) bad router ip address: '%s'", + client_config.interface, __func__, str_router); return; } - if (ioctl(fd, SIOCADDRT, &rt)) { - if (errno != EEXIST) - log_line("%s: failed to set route: %s", - client_config.interface, strerror(errno)); - } else - log_line("Gateway router set to: '%s'", str); + + int fd = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE); + if (fd < 0) { + log_line("%s: (%s) netlink socket open failed: %s", + client_config.interface, __func__, strerror(errno)); + return; + } + + // XXX: Probably need to clear out the old default gw. + + if (rtnl_set_default_gw_v4(fd, router.s_addr, 1) < 0) + log_line("%s: (%s) failed to set route: %s", + client_config.interface, __func__, strerror(errno)); + else + log_line("Gateway router set to: '%s'", str_router); close(fd); }