/**
* Copyright (C) 2012-2014 Steven Barth <steven@midlink.org>
+ * Copyright (C) 2017-2018 Hans Dedecker <dedeckeh@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License v2 as published by
*
*/
+#include <errno.h>
#include <fcntl.h>
-#include <ifaddrs.h>
#include <stdio.h>
#include <signal.h>
#include <string.h>
#include <stdbool.h>
#include <syslog.h>
#include <unistd.h>
+#include <resolv.h>
+#include <alloca.h>
#include <net/if.h>
#include <arpa/inet.h>
+#include <sys/ioctl.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include "odhcp6c.h"
#include "ra.h"
-
static bool nocarrier = false;
+static bool ptp_link = false;
static int sock = -1, rtnl = -1;
static int if_index = 0;
static char if_name[IF_NAMESIZE] = {0};
static volatile int rs_attempt = 0;
static struct in6_addr lladdr = IN6ADDR_ANY_INIT;
+static unsigned int ra_options = 0;
+static unsigned int ra_holdoff_interval = 0;
+static int ra_hoplimit = 0;
+static int ra_mtu = 0;
+static int ra_reachable = 0;
+static int ra_retransmit = 0;
struct {
struct icmp6_hdr hdr;
.lladdr = {ND_OPT_SOURCE_LINKADDR, 1, {0}},
};
-
static void ra_send_rs(int signal __attribute__((unused)));
-int ra_init(const char *ifname, const struct in6_addr *ifid)
+int ra_init(const char *ifname, const struct in6_addr *ifid,
+ unsigned int options, unsigned int holdoff_interval)
{
+ struct ifreq ifr;
+
+ ra_options = options;
+ ra_holdoff_interval = holdoff_interval;
+
const pid_t ourpid = getpid();
sock = socket(AF_INET6, SOCK_RAW | SOCK_CLOEXEC, IPPROTO_ICMPV6);
if (sock < 0)
- return -1;
+ goto failure;
+
+ memset(&ifr, 0, sizeof(ifr));
+ strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name) - 1);
+ if (ioctl(sock, SIOCGIFFLAGS, &ifr) < 0)
+ goto failure;
+
+ ptp_link = !!(ifr.ifr_flags & IFF_POINTOPOINT);
- if_index = if_nametoindex(ifname);
- if (!if_index)
- return -1;
+ memset(&ifr, 0, sizeof(ifr));
+ strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name) - 1);
+ if (ioctl(sock, SIOCGIFINDEX, &ifr) < 0)
+ goto failure;
- strncpy(if_name, ifname, sizeof(if_name) - 1);
+ if_index = ifr.ifr_ifindex;
lladdr = *ifid;
rtnl = socket(AF_NETLINK, SOCK_DGRAM | SOCK_CLOEXEC, NETLINK_ROUTE);
if (rtnl < 0)
- return -1;
+ goto failure;
struct sockaddr_nl rtnl_kernel = { .nl_family = AF_NETLINK };
if (connect(rtnl, (const struct sockaddr*)&rtnl_kernel, sizeof(rtnl_kernel)) < 0)
- return -1;
+ goto failure;
int val = RTNLGRP_LINK;
- setsockopt(rtnl, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &val, sizeof(val));
- fcntl(rtnl, F_SETOWN, ourpid);
- fcntl(rtnl, F_SETFL, fcntl(sock, F_GETFL) | O_ASYNC);
+ if (setsockopt(rtnl, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &val, sizeof(val)) < 0)
+ goto failure;
+
+ if (fcntl(rtnl, F_SETOWN, ourpid) < 0)
+ goto failure;
+
+ if (fcntl(rtnl, F_SETFL, fcntl(sock, F_GETFL) | O_ASYNC) < 0)
+ goto failure;
struct {
struct nlmsghdr hdr;
.hdr = {sizeof(req), RTM_GETLINK, NLM_F_REQUEST, 1, 0},
.ifi = {.ifi_index = if_index}
};
- send(rtnl, &req, sizeof(req), 0);
+ if (send(rtnl, &req, sizeof(req), 0) < 0)
+ goto failure;
+
ra_link_up();
// Filter ICMPv6 package types
struct icmp6_filter filt;
ICMP6_FILTER_SETBLOCKALL(&filt);
ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt);
- setsockopt(sock, IPPROTO_ICMPV6, ICMP6_FILTER, &filt, sizeof(filt));
+ if (setsockopt(sock, IPPROTO_ICMPV6, ICMP6_FILTER, &filt, sizeof(filt)) < 0)
+ goto failure;
// Bind to all-nodes
struct ipv6_mreq an = {ALL_IPV6_NODES, if_index};
- setsockopt(sock, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &an, sizeof(an));
+ if (setsockopt(sock, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &an, sizeof(an)) < 0)
+ goto failure;
// Let the kernel compute our checksums
val = 2;
- setsockopt(sock, IPPROTO_RAW, IPV6_CHECKSUM, &val, sizeof(val));
+ if (setsockopt(sock, IPPROTO_RAW, IPV6_CHECKSUM, &val, sizeof(val)) < 0)
+ goto failure;
// This is required by RFC 4861
val = 255;
- setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &val, sizeof(val));
+ if (setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &val, sizeof(val)) < 0)
+ goto failure;
// Receive multicast hops
val = 1;
- setsockopt(sock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &val, sizeof(val));
+ if (setsockopt(sock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &val, sizeof(val)) < 0)
+ goto failure;
// Bind to one device
- setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname));
+ if (setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname)) < 0)
+ goto failure;
// Add async-mode
- fcntl(sock, F_SETOWN, ourpid);
- fcntl(sock, F_SETFL, fcntl(sock, F_GETFL) | O_ASYNC);
+ if (fcntl(sock, F_SETOWN, ourpid) < 0)
+ goto failure;
+
+ val = fcntl(sock, F_GETFL);
+ if (val < 0)
+ goto failure;
+
+ if (fcntl(sock, F_SETFL, val | O_ASYNC) < 0)
+ goto failure;
// Send RS
signal(SIGALRM, ra_send_rs);
ra_send_rs(SIGALRM);
return 0;
-}
+failure:
+ if (sock >= 0)
+ close(sock);
+
+ if (rtnl >= 0)
+ close(rtnl);
+
+ return -1;
+}
static void ra_send_rs(int signal __attribute__((unused)))
{
else
len = sizeof(struct icmp6_hdr);
- sendto(sock, &rs, len, MSG_DONTWAIT, (struct sockaddr*)&dest, sizeof(dest));
+ if (sendto(sock, &rs, len, MSG_DONTWAIT, (struct sockaddr*)&dest, sizeof(dest)) < 0)
+ syslog(LOG_ERR, "Failed to send RS (%s)", strerror(errno));
if (++rs_attempt <= 3)
alarm(4);
}
-
static int16_t pref_to_priority(uint8_t flags)
{
flags = (flags >> 3) & 0x03;
- return (flags == 0x0) ? 1024 : (flags == 0x1) ? 512 :
- (flags == 0x3) ? 2048 : -1;
-}
-
-static void update_proc(const char *sect, const char *opt, uint32_t value)
-{
- char buf[64];
- snprintf(buf, sizeof(buf), "/proc/sys/net/ipv6/%s/%s/%s", sect, if_name, opt);
-
- int fd = open(buf, O_WRONLY);
- write(fd, buf, snprintf(buf, sizeof(buf), "%u", value));
- close(fd);
+ return (flags == 0x0) ? 512 : (flags == 0x1) ? 384 :
+ (flags == 0x3) ? 640 : -1;
}
-
bool ra_link_up(void)
{
static bool firstcall = true;
struct ifinfomsg msg;
uint8_t pad[4000];
} resp;
-
bool ret = false;
ssize_t read;
do {
read = recv(rtnl, &resp, sizeof(resp), MSG_DONTWAIT);
+
if (read < 0 || !NLMSG_OK(&resp.hdr, (size_t)read) ||
resp.hdr.nlmsg_type != RTM_NEWLINK ||
resp.msg.ifi_index != if_index)
return opt == end;
}
+static bool ra_set_hoplimit(int val)
+{
+ if (val > 0 && val != ra_hoplimit) {
+ ra_hoplimit = val;
+ return true;
+ }
+
+ return false;
+}
+
+static bool ra_set_mtu(int val)
+{
+ if (val >= 1280 && val <= 65535 && ra_mtu != val) {
+ ra_mtu = val;
+ return true;
+ }
+
+ return false;
+}
+
+static bool ra_set_reachable(int val)
+{
+ if (val > 0 && val <= 3600000 && ra_reachable != val) {
+ ra_reachable = val;
+ return true;
+ }
+
+ return false;
+}
+
+static bool ra_set_retransmit(int val)
+{
+ if (val > 0 && val <= 60000 && ra_retransmit != val) {
+ ra_retransmit = val;
+ return true;
+ }
+
+ return false;
+}
+
+int ra_get_hoplimit(void)
+{
+ return ra_hoplimit;
+}
+
+int ra_get_mtu(void)
+{
+ return ra_mtu;
+}
+
+int ra_get_reachable(void)
+{
+ return ra_reachable;
+}
+
+int ra_get_retransmit(void)
+{
+ return ra_retransmit;
+}
+
bool ra_process(void)
{
bool found = false;
bool changed = false;
- bool has_lladdr = !IN6_IS_ADDR_UNSPECIFIED(&lladdr);
- uint8_t buf[1500], cmsg_buf[128];
+ uint8_t buf[1500] _aligned(4);
+ union {
+ struct cmsghdr hdr;
+ uint8_t buf[CMSG_SPACE(sizeof(int))];
+ } cmsg_buf;
struct nd_router_advert *adv = (struct nd_router_advert*)buf;
- struct odhcp6c_entry entry = {IN6ADDR_ANY_INIT, 0, 0, IN6ADDR_ANY_INIT, 0, 0, 0, 0, 0, 0};
+ struct odhcp6c_entry *entry = alloca(sizeof(*entry) + 256);
const struct in6_addr any = IN6ADDR_ANY_INIT;
- if (!has_lladdr) {
- // Autodetect interface-id if not specified
- struct ifaddrs *ifaddr, *ifa;
-
- if (getifaddrs(&ifaddr) == 0) {
- for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
- struct sockaddr_in6 *addr;
-
- if (ifa->ifa_addr == NULL || ifa->ifa_addr->sa_family != AF_INET6)
- continue;
-
- addr = (struct sockaddr_in6*)ifa->ifa_addr;
+ memset(entry, 0, sizeof(*entry));
- if (!IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr))
- continue;
+ if (IN6_IS_ADDR_UNSPECIFIED(&lladdr)) {
+ struct sockaddr_in6 addr = {AF_INET6, 0, 0, ALL_IPV6_ROUTERS, if_index};
+ socklen_t alen = sizeof(addr);
+ int sock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
- if (!strcmp(ifa->ifa_name, if_name)) {
- lladdr = addr->sin6_addr;
- has_lladdr = true;
- break;
- }
- }
+ if (sock >= 0) {
+ if (!connect(sock, (struct sockaddr*)&addr, sizeof(addr)) &&
+ !getsockname(sock, (struct sockaddr*)&addr, &alen))
+ lladdr = addr.sin6_addr;
- freeifaddrs(ifaddr);
+ close(sock);
}
}
while (true) {
struct sockaddr_in6 from;
struct iovec iov = {buf, sizeof(buf)};
- struct msghdr msg = {&from, sizeof(from), &iov, 1,
- cmsg_buf, sizeof(cmsg_buf), 0};
+ struct msghdr msg = {
+ .msg_name = (void *) &from,
+ .msg_namelen = sizeof(from),
+ .msg_iov = &iov,
+ .msg_iovlen = 1,
+ .msg_control = cmsg_buf.buf,
+ .msg_controllen = sizeof(cmsg_buf),
+ .msg_flags = 0
+ };
+ struct icmpv6_opt *opt;
+ uint32_t router_valid;
+ int hlim = 0;
ssize_t len = recvmsg(sock, &msg, MSG_DONTWAIT);
if (len <= 0)
break;
- if (!has_lladdr)
+ if (IN6_IS_ADDR_UNSPECIFIED(&lladdr))
continue;
- int hlim = 0;
for (struct cmsghdr *ch = CMSG_FIRSTHDR(&msg); ch != NULL;
ch = CMSG_NXTHDR(&msg, ch))
if (ch->cmsg_level == IPPROTO_IPV6 &&
if (!ra_icmpv6_valid(&from, hlim, buf, len))
continue;
- // Stop sending solicits
- if (rs_attempt > 0) {
- alarm(0);
- rs_attempt = 0;
- }
-
if (!found) {
- odhcp6c_expire();
+ odhcp6c_expire(false);
found = true;
}
- uint32_t router_valid = ntohs(adv->nd_ra_router_lifetime);
+
+ router_valid = ntohs(adv->nd_ra_router_lifetime);
+
+ /* RFC4861 ยง6.3.7
+ * Once the host sends a Router Solicitation, and receives a valid
+ * Router Advertisement with a non-zero Router Lifetime, the host MUST
+ * desist from sending additional solicitations on that interface
+ * Moreover, a host SHOULD send at least one solicitation in the case
+ * where an advertisement is received prior to having sent a solicitation.
+ */
+ if (rs_attempt > 0 && router_valid > 0) {
+ alarm(0);
+ rs_attempt = 0;
+ }
// Parse default route
- entry.target = any;
- entry.length = 0;
- entry.router = from.sin6_addr;
- entry.priority = pref_to_priority(adv->nd_ra_flags_reserved);
- if (entry.priority < 0)
- entry.priority = pref_to_priority(0);
- entry.valid = router_valid;
- entry.preferred = entry.valid;
- changed |= odhcp6c_update_entry(STATE_RA_ROUTE, &entry);
+ entry->target = any;
+ entry->length = 0;
+ entry->router = from.sin6_addr;
+ entry->priority = pref_to_priority(adv->nd_ra_flags_reserved);
+ if (entry->priority < 0)
+ entry->priority = pref_to_priority(0);
+
+ entry->valid = router_valid;
+ entry->preferred = entry->valid;
+ changed |= odhcp6c_update_entry(STATE_RA_ROUTE, entry,
+ 0, ra_holdoff_interval);
// Parse hoplimit
- if (adv->nd_ra_curhoplimit)
- update_proc("conf", "hop_limit", adv->nd_ra_curhoplimit);
+ changed |= ra_set_hoplimit(adv->nd_ra_curhoplimit);
// Parse ND parameters
- uint32_t reachable = ntohl(adv->nd_ra_reachable);
- if (reachable > 0 && reachable <= 3600000)
- update_proc("neigh", "base_reachable_time_ms", reachable);
-
- uint32_t retransmit = ntohl(adv->nd_ra_retransmit);
- if (retransmit > 0 && retransmit <= 60000)
- update_proc("neigh", "retrans_time_ms", retransmit);
-
+ changed |= ra_set_reachable(ntohl(adv->nd_ra_reachable));
+ changed |= ra_set_retransmit(ntohl(adv->nd_ra_retransmit));
// Evaluate options
- struct icmpv6_opt *opt;
icmpv6_for_each_option(opt, &adv[1], &buf[len]) {
if (opt->type == ND_OPT_MTU) {
uint32_t *mtu = (uint32_t*)&opt->data[2];
- if (ntohl(*mtu) >= 1280 && ntohl(*mtu) <= 65535)
- update_proc("conf", "mtu", ntohl(*mtu));
+ changed |= ra_set_mtu(ntohl(*mtu));
} else if (opt->type == ND_OPT_ROUTE_INFORMATION && opt->len <= 3) {
- entry.router = from.sin6_addr;
- entry.target = any;
- entry.priority = pref_to_priority(opt->data[1]);
- entry.length = opt->data[0];
- uint32_t *valid = (uint32_t*)&opt->data[2];
- entry.valid = ntohl(*valid);
- memcpy(&entry.target, &opt->data[6], (opt->len - 1) * 8);
+ struct icmpv6_opt_route_info *ri = (struct icmpv6_opt_route_info *)opt;
+
+ if (ri->prefix_len > 128) {
+ continue;
+ } else if (ri->prefix_len > 64) {
+ if (ri->len < 2)
+ continue;
+ } else if (ri->prefix_len > 0) {
+ if (ri->len < 1)
+ continue;
+ }
+
+ entry->router = from.sin6_addr;
+ entry->target = any;
+ entry->priority = pref_to_priority(ri->flags);
+ entry->length = ri->prefix_len;
+ entry->valid = ntohl(ri->lifetime);
+ memcpy(&entry->target, ri->prefix, (ri->len - 1) * 8);
- if (entry.length > 128 || IN6_IS_ADDR_LINKLOCAL(&entry.target)
- || IN6_IS_ADDR_LOOPBACK(&entry.target)
- || IN6_IS_ADDR_MULTICAST(&entry.target))
+ if (IN6_IS_ADDR_LINKLOCAL(&entry->target)
+ || IN6_IS_ADDR_LOOPBACK(&entry->target)
+ || IN6_IS_ADDR_MULTICAST(&entry->target))
continue;
- if (entry.priority > 0)
- changed |= odhcp6c_update_entry(STATE_RA_ROUTE, &entry);
+ if (entry->priority > 0)
+ changed |= odhcp6c_update_entry(STATE_RA_ROUTE, entry,
+ 0, ra_holdoff_interval);
} else if (opt->type == ND_OPT_PREFIX_INFORMATION && opt->len == 4) {
struct nd_opt_prefix_info *pinfo = (struct nd_opt_prefix_info*)opt;
- entry.router = any;
- entry.target = pinfo->nd_opt_pi_prefix;
- entry.priority = 256;
- entry.length = pinfo->nd_opt_pi_prefix_len;
- entry.valid = ntohl(pinfo->nd_opt_pi_valid_time);
- entry.preferred = ntohl(pinfo->nd_opt_pi_preferred_time);
-
- if (entry.length > 128 || IN6_IS_ADDR_LINKLOCAL(&entry.target)
- || IN6_IS_ADDR_LOOPBACK(&entry.target)
- || IN6_IS_ADDR_MULTICAST(&entry.target)
- || entry.valid < entry.preferred)
+ entry->router = any;
+ entry->target = pinfo->nd_opt_pi_prefix;
+ entry->priority = 256;
+ entry->length = pinfo->nd_opt_pi_prefix_len;
+ entry->valid = ntohl(pinfo->nd_opt_pi_valid_time);
+ entry->preferred = ntohl(pinfo->nd_opt_pi_preferred_time);
+
+ if (entry->length > 128 || IN6_IS_ADDR_LINKLOCAL(&entry->target)
+ || IN6_IS_ADDR_LOOPBACK(&entry->target)
+ || IN6_IS_ADDR_MULTICAST(&entry->target)
+ || entry->valid < entry->preferred)
continue;
- if (pinfo->nd_opt_pi_flags_reserved & ND_OPT_PI_FLAG_ONLINK)
- changed |= odhcp6c_update_entry_safe(STATE_RA_ROUTE, &entry, 7200);
+ if ((pinfo->nd_opt_pi_flags_reserved & ND_OPT_PI_FLAG_ONLINK) &&
+ !ptp_link)
+ changed |= odhcp6c_update_entry(STATE_RA_ROUTE, entry,
+ 7200, ra_holdoff_interval);
if (!(pinfo->nd_opt_pi_flags_reserved & ND_OPT_PI_FLAG_AUTO) ||
pinfo->nd_opt_pi_prefix_len != 64)
continue;
- entry.target.s6_addr32[2] = lladdr.s6_addr32[2];
- entry.target.s6_addr32[3] = lladdr.s6_addr32[3];
+ entry->target.s6_addr32[2] = lladdr.s6_addr32[2];
+ entry->target.s6_addr32[3] = lladdr.s6_addr32[3];
- changed |= odhcp6c_update_entry_safe(STATE_RA_PREFIX, &entry, 7200);
+ changed |= odhcp6c_update_entry(STATE_RA_PREFIX, entry,
+ 7200, ra_holdoff_interval);
} else if (opt->type == ND_OPT_RECURSIVE_DNS && opt->len > 2) {
- entry.router = from.sin6_addr;
- entry.priority = 0;
- entry.length = 128;
+ entry->router = from.sin6_addr;
+ entry->priority = 0;
+ entry->length = 128;
uint32_t *valid = (uint32_t*)&opt->data[2];
- entry.valid = ntohl(*valid);
- entry.preferred = 0;
+ entry->valid = ntohl(*valid);
+ entry->preferred = 0;
for (ssize_t i = 0; i < (opt->len - 1) / 2; ++i) {
- memcpy(&entry.target, &opt->data[6 + i * sizeof(entry.target)],
- sizeof(entry.target));
- changed |= odhcp6c_update_entry(STATE_RA_DNS, &entry);
+ memcpy(&entry->target, &opt->data[6 + i * sizeof(entry->target)],
+ sizeof(entry->target));
+ changed |= odhcp6c_update_entry(STATE_RA_DNS, entry,
+ 0, ra_holdoff_interval);
+ }
+ } else if (opt->type == ND_OPT_DNSSL && opt->len > 1) {
+ uint32_t *valid = (uint32_t*)&opt->data[2];
+ uint8_t *buf = &opt->data[6];
+ uint8_t *end = &buf[(opt->len - 1) * 8];
+
+ entry->router = from.sin6_addr;
+ entry->valid = ntohl(*valid);
+
+ while (buf < end) {
+ int len = dn_expand(buf, end, buf, (char*)entry->auxtarget, 256);
+ if (len < 1)
+ break;
+
+ buf = &buf[len];
+ entry->auxlen = strlen((char*)entry->auxtarget);
+
+ if (entry->auxlen == 0)
+ continue;
+
+ changed |= odhcp6c_update_entry(STATE_RA_SEARCH, entry,
+ 0, ra_holdoff_interval);
+ entry->auxlen = 0;
}
}
}
- size_t ra_dns_len;
- struct odhcp6c_entry *entry = odhcp6c_get_state(STATE_RA_DNS, &ra_dns_len);
- for (size_t i = 0; i < ra_dns_len / sizeof(*entry); ++i)
- if (IN6_ARE_ADDR_EQUAL(&entry[i].router, &from.sin6_addr) &&
- entry[i].valid > router_valid)
- entry[i].valid = router_valid;
+ if (ra_options & RA_RDNSS_DEFAULT_LIFETIME) {
+ int states[2] = {STATE_RA_DNS, STATE_RA_SEARCH};
+
+ for (size_t i = 0; i < 2; ++i) {
+ size_t ra_dns_len;
+ uint8_t *start = odhcp6c_get_state(states[i], &ra_dns_len);
+
+ for (struct odhcp6c_entry *c = (struct odhcp6c_entry*)start;
+ (uint8_t*)c < &start[ra_dns_len] &&
+ (uint8_t*)odhcp6c_next_entry(c) <= &start[ra_dns_len];
+ c = odhcp6c_next_entry(c)) {
+ if (IN6_ARE_ADDR_EQUAL(&c->router, &from.sin6_addr) &&
+ c->valid > router_valid)
+ c->valid = router_valid;
+ }
+ }
+ }
}
if (found)
- odhcp6c_expire();
+ odhcp6c_expire(false);
return found && changed;
}
projects / project / odhcp6c.git / blobdiff