#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/netlink.h>
-#include <linux/if_addr.h>
-#include <linux/neighbour.h>
-#include <linux/rtnetlink.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/wait.h>
#include <sys/syscall.h>
-#include <netlink/msg.h>
-#include <netlink/socket.h>
-#include <netlink/attr.h>
#include <libubox/uloop.h>
#include "odhcpd.h"
static int ioctl_sock;
-static struct nl_sock *rtnl_socket = NULL;
static int urandom_fd = -1;
static void sighandler(_unused int signal)
);
}
+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);
ioctl_sock = socket(AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, 0);
- if (!(rtnl_socket = odhcpd_create_nl_socket(NETLINK_ROUTE))) {
- syslog(LOG_ERR, "Unable to open nl 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(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;
}
-struct nl_sock *odhcpd_create_nl_socket(int protocol)
-{
- struct nl_sock *nl_sock;
-
- nl_sock = nl_socket_alloc();
- if (!nl_sock)
- goto err;
-
- if (nl_connect(nl_sock, protocol) < 0)
- goto err;
-
- return nl_sock;
-
-err:
- if (nl_sock)
- nl_socket_free(nl_sock);
-
- return NULL;
-}
-
-// Read IPv6 MTU for interface
+/* Read IPv6 MTU for interface */
int odhcpd_get_interface_config(const char *ifname, const char *what)
{
char buf[64];
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);
}
-// 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 = {
.msg_name = (void *) dest,
.msg_flags = 0
};
- // Set control data (define destination interface)
+ /* 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;
ssize_t sent = sendmsg(socket, &msg, MSG_DONTWAIT);
if (sent < 0)
- syslog(LOG_NOTICE, "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_DEBUG, "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;
}
-struct addr_info {
- int ifindex;
- struct odhcpd_ipaddr *addrs;
- size_t addrs_sz;
- int pending;
- ssize_t ret;
-};
-static int cb_valid_handler(struct nl_msg *msg, void *arg)
+static int odhcpd_get_linklocal_interface_address(int ifindex, struct in6_addr *lladdr)
{
- struct addr_info *ctxt = (struct addr_info *)arg;
- struct nlmsghdr *hdr = nlmsg_hdr(msg);
- struct ifaddrmsg *ifa;
- struct nlattr *nla[__IFA_MAX];
-
- if (hdr->nlmsg_type != RTM_NEWADDR || ctxt->ret >= (ssize_t)ctxt->addrs_sz)
- return NL_SKIP;
-
- ifa = NLMSG_DATA(hdr);
- if (ifa->ifa_scope != RT_SCOPE_UNIVERSE ||
- (ctxt->ifindex && ifa->ifa_index != (unsigned)ctxt->ifindex))
- return NL_SKIP;
-
- nlmsg_parse(hdr, sizeof(*ifa), nla, __IFA_MAX - 1, NULL);
- if (!nla[IFA_ADDRESS])
- return NL_SKIP;
-
- memset(&ctxt->addrs[ctxt->ret], 0, sizeof(ctxt->addrs[ctxt->ret]));
- ctxt->addrs[ctxt->ret].prefix = ifa->ifa_prefixlen;
-
- nla_memcpy(&ctxt->addrs[ctxt->ret].addr, nla[IFA_ADDRESS],
- sizeof(ctxt->addrs[ctxt->ret].addr));
-
- if (nla[IFA_CACHEINFO]) {
- struct ifa_cacheinfo *ifc = nla_data(nla[IFA_CACHEINFO]);
-
- ctxt->addrs[ctxt->ret].preferred = ifc->ifa_prefered;
- ctxt->addrs[ctxt->ret].valid = ifc->ifa_valid;
- }
-
- if (ifa->ifa_flags & IFA_F_DEPRECATED)
- ctxt->addrs[ctxt->ret].preferred = 0;
-
- ctxt->ret++;
-
- return NL_OK;
-}
-
-static int cb_finish_handler(_unused struct nl_msg *msg, void *arg)
-{
- struct addr_info *ctxt = (struct addr_info *)arg;
-
- ctxt->pending = 0;
-
- return NL_STOP;
-}
-
-static int cb_error_handler(_unused struct sockaddr_nl *nla, struct nlmsgerr *err,
- void *arg)
-{
- struct addr_info *ctxt = (struct addr_info *)arg;
-
- ctxt->pending = 0;
- ctxt->ret = err->error;
-
- return NL_STOP;
-}
-
-// 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)
-{
- struct nl_msg *msg;
- struct ifaddrmsg ifa = {
- .ifa_family = AF_INET6,
- .ifa_prefixlen = 0,
- .ifa_flags = 0,
- .ifa_scope = 0,
- .ifa_index = ifindex, };
- struct nl_cb *cb = nl_cb_alloc(NL_CB_DEFAULT);
- struct addr_info ctxt = {
- .ifindex = ifindex,
- .addrs = addrs,
- .addrs_sz = cnt,
- .ret = 0,
- .pending = 1,
- };
-
- if (!cb) {
- ctxt.ret = -1;
- goto out;
- }
-
- msg = nlmsg_alloc_simple(RTM_GETADDR, NLM_F_REQUEST | NLM_F_DUMP);
-
- if (!msg) {
- ctxt.ret = - 1;
- goto out;
- }
-
- nlmsg_append(msg, &ifa, sizeof(ifa), 0);
-
- nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, cb_valid_handler, &ctxt);
- nl_cb_set(cb, NL_CB_FINISH, NL_CB_CUSTOM, cb_finish_handler, &ctxt);
- nl_cb_err(cb, NL_CB_CUSTOM, cb_error_handler, &ctxt);
-
- nl_send_auto_complete(rtnl_socket, msg);
- while (ctxt.pending > 0)
- nl_recvmsgs(rtnl_socket, cb);
-
- nlmsg_free(msg);
-out:
- nl_cb_put(cb);
-
- return ctxt.ret;
-}
-
-int odhcpd_get_linklocal_interface_address(int ifindex, struct in6_addr *lladdr)
-{
- int status = -1;
- struct sockaddr_in6 addr = {AF_INET6, 0, 0, ALL_IPV6_ROUTERS, ifindex};
+ int ret = -1;
+ struct sockaddr_in6 addr;
socklen_t alen = sizeof(addr);
int sock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
+ if (sock < 0)
+ return -1;
+
+ 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 (!connect(sock, (struct sockaddr*)&addr, sizeof(addr)) &&
!getsockname(sock, (struct sockaddr*)&addr, &alen)) {
*lladdr = addr.sin6_addr;
- status = 0;
+ ret = 0;
}
close(sock);
-
- return status;
-}
-
-int odhcpd_setup_route(const struct in6_addr *addr, const int prefixlen,
- const struct interface *iface, const struct in6_addr *gw,
- const uint32_t metric, const bool add)
-{
- struct nl_msg *msg;
- struct rtmsg rtm = {
- .rtm_family = AF_INET6,
- .rtm_dst_len = prefixlen,
- .rtm_src_len = 0,
- .rtm_table = RT_TABLE_MAIN,
- .rtm_protocol = (add ? RTPROT_STATIC : RTPROT_UNSPEC),
- .rtm_scope = (add ? (gw ? RT_SCOPE_UNIVERSE : RT_SCOPE_LINK) : RT_SCOPE_NOWHERE),
- .rtm_type = (add ? RTN_UNICAST : RTN_UNSPEC),
- };
- int ret = 0;
-
- msg = nlmsg_alloc_simple(add ? RTM_NEWROUTE : RTM_DELROUTE,
- add ? NLM_F_CREATE | NLM_F_REPLACE : 0);
- if (!msg)
- return -1;
-
- nlmsg_append(msg, &rtm, sizeof(rtm), 0);
-
- nla_put(msg, RTA_DST, sizeof(*addr), addr);
- nla_put_u32(msg, RTA_OIF, iface->ifindex);
- nla_put_u32(msg, RTA_PRIORITY, metric);
-
- if (gw)
- nla_put(msg, RTA_GATEWAY, sizeof(*gw), gw);
-
- ret = nl_send_auto_complete(rtnl_socket, msg);
- nlmsg_free(msg);
-
- if (ret < 0)
- return ret;
-
- return nl_wait_for_ack(rtnl_socket);
+ return ret;
}
-int odhcpd_setup_proxy_neigh(const struct in6_addr *addr,
- const struct interface *iface, const bool add)
+/*
+ * 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)
{
- struct nl_msg *msg;
- struct ndmsg ndm = {
- .ndm_family = AF_INET6,
- .ndm_flags = NTF_PROXY,
- .ndm_ifindex = iface->ifindex,
- };
- int ret = 0, flags = NLM_F_REQUEST;
+ time_t now = odhcpd_time();
+ ssize_t m = -1;
- if (add)
- flags |= NLM_F_REPLACE | NLM_F_CREATE;
+ for (size_t i = 0; i < iface->addr6_len; ++i) {
+ if (iface->addr6[i].valid <= (uint32_t)now)
+ continue;
- msg = nlmsg_alloc_simple(add ? RTM_NEWNEIGH : RTM_DELNEIGH, flags);
- if (!msg)
- return -1;
+ if (m < 0) {
+ m = i;
+ continue;
+ }
- nlmsg_append(msg, &ndm, sizeof(ndm), 0);
+ if (iface->addr6[m].preferred >= (uint32_t)now &&
+ iface->addr6[i].preferred < (uint32_t)now)
+ continue;
- nla_put(msg, NDA_DST, sizeof(*addr), addr);
+ 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;
- ret = nl_send_auto_complete(rtnl_socket, msg);
- nlmsg_free(msg);
+ if (iface->addr6[i].preferred > iface->addr6[m].preferred)
+ m = i;
+ }
- if (ret < 0)
- return ret;
+ if (m >= 0) {
+ *addr = iface->addr6[m].addr.in6;
+ return 0;
+ }
- return nl_wait_for_ack(rtnl_socket);
+ 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;
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)
+ if (e->handle_error && getsockopt(u->fd, SOL_SOCKET, SO_ERROR, &ret, &ret_len) == 0)
e->handle_error(e, ret);
}
}
- // Extract destination interface
+ /* Extract destination interface */
int destiface = 0;
int *hlim = NULL;
void *dest = NULL;
}
}
- // 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_DEBUG, "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, dest);
}
}
-// Register events for the multiplexer
+/* Register events for the multiplexer */
int odhcpd_register(struct odhcpd_event *event)
{
event->uloop.cb = odhcpd_receive_packets;
*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)
{
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);
+}