#include <unistd.h>
#include <signal.h>
#include <stdbool.h>
+#include <syslog.h>
+#include <alloca.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <netinet/ip6.h>
#include <netpacket/packet.h>
-#include <linux/rtnetlink.h>
+#include <linux/netlink.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
static int ioctl_sock;
-static int rtnl_socket = -1;
-static int rtnl_seq = 0;
static int urandom_fd = -1;
+static void sighandler(_unused int signal)
+{
+ uloop_end();
+}
+
+static void print_usage(const char *app)
+{
+ printf(
+ "== %s Usage ==\n\n"
+ " -h, --help Print this help\n"
+ " -l level Specify log level 0..7 (default %d)\n",
+ app, config.log_level
+ );
+}
-int main()
+static bool ipv6_enabled(void)
+{
+ int fd = socket(AF_INET6, SOCK_DGRAM, 0);
+
+ if (fd < 0)
+ return false;
+
+ close(fd);
+
+ return true;
+}
+
+int main(int argc, char **argv)
{
openlog("odhcpd", LOG_PERROR | LOG_PID, LOG_DAEMON);
+ int opt;
+
+ while ((opt = getopt(argc, argv, "hl:")) != -1) {
+ switch (opt) {
+ case 'h':
+ print_usage(argv[0]);
+ return 0;
+ case 'l':
+ config.log_level = (atoi(optarg) & LOG_PRIMASK);
+ fprintf(stderr, "Log level set to %d\n", config.log_level);
+ break;
+ }
+ }
+ setlogmask(LOG_UPTO(config.log_level));
uloop_init();
if (getuid() != 0) {
ioctl_sock = socket(AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, 0);
- if ((rtnl_socket = odhcpd_open_rtnl()) < 0) {
- syslog(LOG_ERR, "Unable to open socket: %s", strerror(errno));
- return 2;
- }
+ if (ioctl_sock < 0)
+ return 4;
if ((urandom_fd = open("/dev/urandom", O_RDONLY | O_CLOEXEC)) < 0)
return 4;
signal(SIGUSR1, SIG_IGN);
+ signal(SIGINT, sighandler);
+ signal(SIGTERM, sighandler);
- if (init_router())
+ if (netlink_init())
return 4;
- if (init_dhcpv6())
- return 4;
+ if (ipv6_enabled()) {
+ if (router_init())
+ return 4;
- if (init_ndp())
- return 4;
+ if (dhcpv6_init())
+ return 4;
- if (init_dhcpv4())
+ if (ndp_init())
+ return 4;
+ }
+#ifndef DHCPV4_SUPPORT
+ else
return 4;
+#else
+ if (dhcpv4_init())
+ return 4;
+#endif
odhcpd_run();
return 0;
}
-int odhcpd_open_rtnl(void)
-{
- int sock = socket(AF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, NETLINK_ROUTE);
- // Connect to the kernel netlink interface
- struct sockaddr_nl nl = {.nl_family = AF_NETLINK};
- if (connect(sock, (struct sockaddr*)&nl, sizeof(nl))) {
- syslog(LOG_ERR, "Failed to connect to kernel rtnetlink: %s",
- strerror(errno));
- return -1;
- }
-
- return sock;
-}
-
-
-// Read IPv6 MTU for interface
-int odhcpd_get_interface_mtu(const char *ifname)
+/* Read IPv6 MTU for interface */
+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);
+ if (fd < 0)
+ return -1;
+
ssize_t len = read(fd, buf, sizeof(buf) - 1);
close(fd);
if (len < 0)
return -1;
-
buf[len] = 0;
return atoi(buf);
-
}
-// Read IPv6 MAC for interface
+/* Read IPv6 MAC for interface */
int odhcpd_get_mac(const struct interface *iface, uint8_t mac[6])
{
struct ifreq ifr;
+
memset(&ifr, 0, sizeof(ifr));
- strncpy(ifr.ifr_name, iface->ifname, sizeof(ifr.ifr_name));
+ strncpy(ifr.ifr_name, iface->ifname, sizeof(ifr.ifr_name) - 1);
if (ioctl(ioctl_sock, SIOCGIFHWADDR, &ifr) < 0)
return -1;
+
memcpy(mac, ifr.ifr_hwaddr.sa_data, 6);
return 0;
}
-// Forwards a packet on a specific interface
+/* Forwards a packet on a specific interface */
ssize_t odhcpd_send(int socket, struct sockaddr_in6 *dest,
struct iovec *iov, size_t iov_len,
const struct interface *iface)
{
- // Construct headers
+ /* 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};
-
- // Set control data (define destination interface)
+ 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);
chdr->cmsg_level = IPPROTO_IPV6;
chdr->cmsg_type = IPV6_PKTINFO;
struct in6_pktinfo *pktinfo = (struct in6_pktinfo*)CMSG_DATA(chdr);
pktinfo->ipi6_ifindex = iface->ifindex;
- // Also set scope ID if link-local
+ /* Also set scope ID if link-local */
if (IN6_IS_ADDR_LINKLOCAL(&dest->sin6_addr)
|| 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));
ssize_t sent = sendmsg(socket, &msg, MSG_DONTWAIT);
if (sent < 0)
- syslog(LOG_WARNING, "Failed to send to %s%%%s (%s)",
- ipbuf, iface->ifname, strerror(errno));
+ syslog(LOG_NOTICE, "Failed to send to %s%%%s@%s (%m)",
+ ipbuf, iface->name, iface->ifname);
else
- syslog(LOG_NOTICE, "Sent %li bytes to %s%%%s",
- (long)sent, ipbuf, iface->ifname);
+ syslog(LOG_DEBUG, "Sent %zd bytes to %s%%%s@%s",
+ sent, ipbuf, iface->name, iface->ifname);
return sent;
}
-// Detect an IPV6-address currently assigned to the given interface
-ssize_t odhcpd_get_interface_addresses(int ifindex,
- struct odhcpd_ipaddr *addrs, size_t cnt)
+static int odhcpd_get_linklocal_interface_address(int ifindex, struct in6_addr *lladdr)
{
- struct {
- struct nlmsghdr nhm;
- struct ifaddrmsg ifa;
- } req = {{sizeof(req), RTM_GETADDR, NLM_F_REQUEST | NLM_F_DUMP,
- ++rtnl_seq, 0}, {AF_INET6, 0, 0, 0, ifindex}};
- if (send(rtnl_socket, &req, sizeof(req), 0) < (ssize_t)sizeof(req))
- return 0;
+ int ret = -1;
+ struct sockaddr_in6 addr;
+ socklen_t alen = sizeof(addr);
+ int sock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
- uint8_t buf[8192];
- ssize_t len = 0, ret = 0;
+ if (sock < 0)
+ return -1;
- for (struct nlmsghdr *nhm = NULL; ; nhm = NLMSG_NEXT(nhm, len)) {
- while (len < 0 || !NLMSG_OK(nhm, (size_t)len)) {
- len = recv(rtnl_socket, buf, sizeof(buf), 0);
- nhm = (struct nlmsghdr*)buf;
- if (len < 0 || !NLMSG_OK(nhm, (size_t)len)) {
- if (errno == EINTR)
- continue;
- else
- return ret;
- }
- }
+ memset(&addr, 0, sizeof(addr));
+ addr.sin6_family = AF_INET6;
+ inet_pton(AF_INET6, ALL_IPV6_ROUTERS, &addr.sin6_addr);
+ addr.sin6_scope_id = ifindex;
- if (nhm->nlmsg_type != RTM_NEWADDR)
- break;
+ if (!connect(sock, (struct sockaddr*)&addr, sizeof(addr)) &&
+ !getsockname(sock, (struct sockaddr*)&addr, &alen)) {
+ *lladdr = addr.sin6_addr;
+ ret = 0;
+ }
- // Skip address but keep clearing socket buffer
- if (ret >= (ssize_t)cnt)
+ close(sock);
+ return ret;
+}
+
+/*
+ * DNS address selection criteria order :
+ * - use IPv6 address with valid lifetime if none is yet selected
+ * - use IPv6 address with a preferred lifetime if the already selected IPv6 address is deprecated
+ * - use an IPv6 ULA address if the already selected IPv6 address is not an ULA address
+ * - use the IPv6 address with the longest preferred lifetime
+ */
+int odhcpd_get_interface_dns_addr(const struct interface *iface, struct in6_addr *addr)
+{
+ time_t now = odhcpd_time();
+ ssize_t m = -1;
+
+ for (size_t i = 0; i < iface->addr6_len; ++i) {
+ if (iface->addr6[i].valid <= (uint32_t)now)
continue;
- struct ifaddrmsg *ifa = NLMSG_DATA(nhm);
- if (ifa->ifa_scope != RT_SCOPE_UNIVERSE ||
- ifa->ifa_index != (unsigned)ifindex)
+ if (m < 0) {
+ m = i;
continue;
+ }
- struct rtattr *rta = (struct rtattr*)&ifa[1];
- size_t alen = NLMSG_PAYLOAD(nhm, sizeof(*ifa));
- memset(&addrs[ret], 0, sizeof(addrs[ret]));
- addrs[ret].prefix = ifa->ifa_prefixlen;
-
- while (RTA_OK(rta, alen)) {
- if (rta->rta_type == IFA_ADDRESS) {
- memcpy(&addrs[ret].addr, RTA_DATA(rta),
- sizeof(struct in6_addr));
- } else if (rta->rta_type == IFA_CACHEINFO) {
- struct ifa_cacheinfo *ifc = RTA_DATA(rta);
- addrs[ret].preferred = ifc->ifa_prefered;
- addrs[ret].valid = ifc->ifa_valid;
- }
+ if (iface->addr6[m].preferred >= (uint32_t)now &&
+ iface->addr6[i].preferred < (uint32_t)now)
+ continue;
- rta = RTA_NEXT(rta, alen);
- }
+ if (IN6_IS_ADDR_ULA(&iface->addr6[i].addr.in6)) {
+ if (!IN6_IS_ADDR_ULA(&iface->addr6[m].addr.in6)) {
+ m = i;
+ continue;
+ }
+ } else if (IN6_IS_ADDR_ULA(&iface->addr6[m].addr.in6))
+ continue;
- if (ifa->ifa_flags & IFA_F_DEPRECATED)
- addrs[ret].preferred = 0;
+ if (iface->addr6[i].preferred > iface->addr6[m].preferred)
+ m = i;
+ }
- 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;
+ if (m >= 0) {
+ *addr = iface->addr6[m].addr.in6;
+ return 0;
}
- return ret;
+ return odhcpd_get_linklocal_interface_address(iface->ifindex, addr);
}
-
struct interface* odhcpd_get_interface_by_index(int ifindex)
{
struct interface *iface;
- list_for_each_entry(iface, &interfaces, head)
- if (iface->ifindex == ifindex)
- return iface;
- return NULL;
-}
-
-
-struct interface* odhcpd_get_interface_by_name(const char *name)
-{
- struct interface *iface;
- list_for_each_entry(iface, &interfaces, head)
- if (!strcmp(iface->ifname, name))
- return iface;
-
- return NULL;
-}
-
-
-struct interface* odhcpd_get_master_interface(void)
-{
- struct interface *iface;
- list_for_each_entry(iface, &interfaces, head)
- if (iface->master)
+ avl_for_each_element(&interfaces, iface, avl) {
+ if (iface->ifindex == ifindex)
return iface;
+ }
return NULL;
}
-
-// Convenience function to receive and do basic validation of packets
+/* Convenience function to receive and do basic validation of packets */
static void odhcpd_receive_packets(struct uloop_fd *u, _unused unsigned int events)
{
struct odhcpd_event *e = container_of(u, struct odhcpd_event, uloop);
- uint8_t data_buf[RELAYD_BUFFER_SIZE], cmsg_buf[128];
+ uint8_t data_buf[8192], cmsg_buf[128];
union {
struct sockaddr_in6 in6;
struct sockaddr_in in;
struct sockaddr_nl nl;
} addr;
+ if (u->error) {
+ int ret = -1;
+ socklen_t ret_len = sizeof(ret);
+
+ u->error = false;
+ if (e->handle_error && getsockopt(u->fd, SOL_SOCKET, SO_ERROR, &ret, &ret_len) == 0)
+ e->handle_error(e, ret);
+ }
+
+ if (e->recv_msgs) {
+ e->recv_msgs(e);
+ return;
+ }
+
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) {
}
- // Extract destination interface
+ /* Extract destination interface */
int destiface = 0;
int *hlim = NULL;
+ void *dest = NULL;
struct in6_pktinfo *pktinfo;
struct in_pktinfo *pkt4info;
for (struct cmsghdr *ch = CMSG_FIRSTHDR(&msg); ch != NULL; ch = CMSG_NXTHDR(&msg, ch)) {
ch->cmsg_type == IPV6_PKTINFO) {
pktinfo = (struct in6_pktinfo*)CMSG_DATA(ch);
destiface = pktinfo->ipi6_ifindex;
+ dest = &pktinfo->ipi6_addr;
} else if (ch->cmsg_level == IPPROTO_IP &&
ch->cmsg_type == IP_PKTINFO) {
pkt4info = (struct in_pktinfo*)CMSG_DATA(ch);
destiface = pkt4info->ipi_ifindex;
+ dest = &pkt4info->ipi_addr;
} else if (ch->cmsg_level == IPPROTO_IPV6 &&
ch->cmsg_type == IPV6_HOPLIMIT) {
hlim = (int*)CMSG_DATA(ch);
}
}
- // Check hoplimit if received
+ /* Check hoplimit if received */
if (hlim && *hlim != 255)
continue;
- // Detect interface for packet sockets
+ /* Detect interface for packet sockets */
if (addr.ll.sll_family == AF_PACKET)
destiface = addr.ll.sll_ifindex;
- struct interface *iface =
- odhcpd_get_interface_by_index(destiface);
-
- if (!iface && addr.nl.nl_family != AF_NETLINK)
- continue;
-
char ipbuf[INET6_ADDRSTRLEN] = "kernel";
if (addr.ll.sll_family == AF_PACKET &&
len >= (ssize_t)sizeof(struct ip6_hdr))
else if (addr.in.sin_family == AF_INET)
inet_ntop(AF_INET, &addr.in.sin_addr, ipbuf, sizeof(ipbuf));
- syslog(LOG_NOTICE, "--");
- syslog(LOG_NOTICE, "Received %li Bytes from %s%%%s", (long)len,
- ipbuf, (iface) ? iface->ifname : "netlink");
+ /* From netlink */
+ if (addr.nl.nl_family == AF_NETLINK) {
+ syslog(LOG_DEBUG, "Received %zd Bytes from %s%%netlink", len,
+ ipbuf);
+ e->handle_dgram(&addr, data_buf, len, NULL, dest);
+ return;
+ } else if (destiface != 0) {
+ struct interface *iface;
+
+ avl_for_each_element(&interfaces, iface, avl) {
+ if (iface->ifindex != destiface)
+ continue;
+
+ syslog(LOG_DEBUG, "Received %zd Bytes from %s%%%s@%s", len,
+ ipbuf, iface->name, iface->ifname);
+
+ e->handle_dgram(&addr, data_buf, len, iface, dest);
+ }
+ }
+
- e->handle_dgram(&addr, data_buf, len, iface);
}
}
-// Register events for the multiplexer
+/* Register events for the multiplexer */
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));
+}
+
+int odhcpd_deregister(struct odhcpd_event *event)
+{
+ event->uloop.cb = NULL;
+ return uloop_fd_delete(&event->uloop);
}
-void odhcpd_urandom(void *data, size_t len)
+void odhcpd_process(struct odhcpd_event *event)
{
- read(urandom_fd, data, len);
+ odhcpd_receive_packets(&event->uloop, 0);
+}
+
+int odhcpd_urandom(void *data, size_t len)
+{
+ return read(urandom_fd, data, len);
}
}
*dst = 0;
}
+
+const char *odhcpd_print_mac(const uint8_t *mac, const size_t len)
+{
+ static char buf[32];
+
+ snprintf(buf, sizeof(buf), "%02x", mac[0]);
+ for (size_t i = 1, j = 2; i < len && j < sizeof(buf); i++, j += 3)
+ snprintf(buf + j, sizeof(buf) - j, ":%02x", mac[i]);
+
+ return buf;
+}
+
+int odhcpd_bmemcmp(const void *av, const void *bv, size_t bits)
+{
+ const uint8_t *a = av, *b = bv;
+ size_t bytes = bits / 8;
+ bits %= 8;
+
+ int res = memcmp(a, b, bytes);
+ if (res == 0 && bits > 0)
+ res = (a[bytes] >> (8 - bits)) - (b[bytes] >> (8 - bits));
+
+ return res;
+}
+
+
+void odhcpd_bmemcpy(void *av, const void *bv, size_t bits)
+{
+ uint8_t *a = av;
+ const uint8_t *b = bv;
+
+ size_t bytes = bits / 8;
+ bits %= 8;
+ memcpy(a, b, bytes);
+
+ if (bits > 0) {
+ uint8_t mask = (1 << (8 - bits)) - 1;
+ a[bytes] = (a[bytes] & mask) | ((~mask) & b[bytes]);
+ }
+}
+
+
+int odhcpd_netmask2bitlen(bool inet6, void *mask)
+{
+ int bits;
+ struct in_addr *v4;
+ struct in6_addr *v6;
+
+ if (inet6)
+ for (bits = 0, v6 = mask;
+ bits < 128 && (v6->s6_addr[bits / 8] << (bits % 8)) & 128;
+ bits++);
+ else
+ for (bits = 0, v4 = mask;
+ bits < 32 && (ntohl(v4->s_addr) << bits) & 0x80000000;
+ bits++);
+
+ return bits;
+}
+
+bool odhcpd_bitlen2netmask(bool inet6, unsigned int bits, void *mask)
+{
+ uint8_t b;
+ struct in_addr *v4;
+ struct in6_addr *v6;
+
+ if (inet6)
+ {
+ if (bits > 128)
+ return false;
+
+ v6 = mask;
+
+ for (unsigned int i = 0; i < sizeof(v6->s6_addr); i++)
+ {
+ b = (bits > 8) ? 8 : bits;
+ v6->s6_addr[i] = (uint8_t)(0xFF << (8 - b));
+ bits -= b;
+ }
+ }
+ else
+ {
+ if (bits > 32)
+ return false;
+
+ v4 = mask;
+ v4->s_addr = bits ? htonl(~((1 << (32 - bits)) - 1)) : 0;
+ }
+
+ return true;
+}
+
+bool odhcpd_valid_hostname(const char *name)
+{
+#define MAX_LABEL 63
+ const char *c, *label, *label_end;
+ int label_sz = 0;
+
+ for (c = name, label_sz = 0, label = name, label_end = name + strcspn(name, ".") - 1;
+ *c && label_sz <= MAX_LABEL; c++) {
+ if ((*c >= '0' && *c <= '9') ||
+ (*c >= 'A' && *c <= 'Z') ||
+ (*c >= 'a' && *c <= 'z')) {
+ label_sz++;
+ continue;
+ }
+
+ if ((*c == '_' || *c == '-') && c != label && c != label_end) {
+ label_sz++;
+ continue;
+ }
+
+ if (*c == '.') {
+ if (*(c + 1)) {
+ label = c + 1;
+ label_end = label + strcspn(label, ".") - 1;
+ label_sz = 0;
+ }
+ continue;
+ }
+
+ return false;
+ }
+
+ return (label_sz && label_sz <= MAX_LABEL ? true : false);
+}