/*
* dhcpcd - DHCP client daemon
* Copyright (c) 2006-2015 Roy Marples <roy@marples.name>
* All rights reserved
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/param.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <net/if.h>
#include <net/if_arp.h>
#include <netinet/in.h>
#ifdef __FreeBSD__ /* Needed so that including netinet6/in6_var.h works */
# include <net/if_var.h>
#endif
#ifdef AF_LINK
# include <net/if_dl.h>
# include <net/if_types.h>
# include <netinet/in_var.h>
#endif
#ifdef AF_PACKET
# include <netpacket/packet.h>
#endif
#ifdef SIOCGIFMEDIA
# include <net/if_media.h>
#endif
#include <net/route.h>
#include <ctype.h>
#include <errno.h>
#include <ifaddrs.h>
#include <fnmatch.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "config.h"
#include "common.h"
#include "dev.h"
#include "dhcp.h"
#include "dhcp6.h"
#include "if.h"
#include "if-options.h"
#include "ipv4.h"
#include "ipv6nd.h"
#ifdef __QNX__
/* QNX carries defines for, but does not actually support PF_LINK */
#undef IFLR_ACTIVE
#endif
int
split_interface_lease(const char *ifname, int *interface_name_len,
const char **lease_identifier)
{
int ret = 0;
int len;
const char *lease_ptr = ifname;
const char *p = strchr(ifname, '=');
if (interface_name_len)
len = *interface_name_len;
else
len = strlen(ifname);
if (p) {
lease_ptr = p + 1;
if (len > p - ifname)
len = p - ifname;
ret = 1;
}
if (interface_name_len)
*interface_name_len = len;
if (lease_identifier)
*lease_identifier = lease_ptr;
return ret;
}
void
if_free(struct interface *ifp)
{
if (ifp == NULL)
return;
ipv4_free(ifp);
dhcp_free(ifp);
dhcp6_free(ifp);
ipv6nd_free(ifp);
ipv6_free(ifp);
free_options(ifp->options);
free(ifp);
}
int
if_carrier(struct interface *iface)
{
int s, r;
struct ifreq ifr;
#ifdef SIOCGIFMEDIA
struct ifmediareq ifmr;
#endif
if ((s = socket(PF_INET, SOCK_DGRAM, 0)) == -1)
return LINK_UNKNOWN;
memset(&ifr, 0, sizeof(ifr));
strlcpy(ifr.ifr_name, iface->name, sizeof(ifr.ifr_name));
if (ioctl(s, SIOCGIFFLAGS, &ifr) == -1) {
close(s);
return LINK_UNKNOWN;
}
iface->flags = (unsigned int)ifr.ifr_flags;
#ifdef SIOCGIFMEDIA
memset(&ifmr, 0, sizeof(ifmr));
strlcpy(ifmr.ifm_name, iface->name, sizeof(ifmr.ifm_name));
if (ioctl(s, SIOCGIFMEDIA, &ifmr) != -1 &&
ifmr.ifm_status & IFM_AVALID)
r = (ifmr.ifm_status & IFM_ACTIVE) ? LINK_UP : LINK_DOWN;
else
r = ifr.ifr_flags & IFF_RUNNING ? LINK_UP : LINK_UNKNOWN;
#else
r = ifr.ifr_flags & IFF_RUNNING ? LINK_UP : LINK_DOWN;
#endif
close(s);
return r;
}
int
if_setflag(struct interface *ifp, short flag)
{
struct ifreq ifr;
int s, r;
if ((s = socket(PF_INET, SOCK_DGRAM, 0)) == -1)
return -1;
memset(&ifr, 0, sizeof(ifr));
strlcpy(ifr.ifr_name, ifp->name, sizeof(ifr.ifr_name));
r = -1;
if (ioctl(s, SIOCGIFFLAGS, &ifr) == 0) {
if (flag == 0 || (ifr.ifr_flags & flag) == flag)
r = 0;
else {
ifr.ifr_flags |= flag;
if (ioctl(s, SIOCSIFFLAGS, &ifr) == 0)
r = 0;
}
ifp->flags = (unsigned int)ifr.ifr_flags;
}
close(s);
return r;
}
static int
if_hasconf(struct dhcpcd_ctx *ctx, const char *ifname)
{
int i;
for (i = 0; i < ctx->ifcc; i++) {
if (strcmp(ctx->ifcv[i], ifname) == 0)
return 1;
}
return 0;
}
static void if_learnaddrs1(struct dhcpcd_ctx *ctx, struct if_head *ifs,
struct ifaddrs *ifaddrs)
{
struct ifaddrs *ifa;
struct interface *ifp;
#ifdef INET
const struct sockaddr_in *addr, *net, *dst;
#endif
#ifdef INET6
struct sockaddr_in6 *sin6, *net6;
#endif
int ifa_flags;
for (ifa = ifaddrs; ifa; ifa = ifa->ifa_next) {
if (ifa->ifa_addr == NULL)
continue;
if ((ifp = if_find(ifs, ifa->ifa_name)) == NULL)
continue;
switch(ifa->ifa_addr->sa_family) {
#ifdef INET
case AF_INET:
addr = (const struct sockaddr_in *)
(void *)ifa->ifa_addr;
net = (const struct sockaddr_in *)
(void *)ifa->ifa_netmask;
if (ifa->ifa_flags & IFF_POINTOPOINT)
dst = (const struct sockaddr_in *)
(void *)ifa->ifa_dstaddr;
else
dst = NULL;
ifa_flags = if_addrflags(&addr->sin_addr, ifp);
ipv4_handleifa(ctx, RTM_NEWADDR, ifs, ifa->ifa_name,
&addr->sin_addr,
&net->sin_addr,
dst ? &dst->sin_addr : NULL, ifa_flags);
break;
#endif
#ifdef INET6
case AF_INET6:
sin6 = (struct sockaddr_in6 *)(void *)ifa->ifa_addr;
net6 = (struct sockaddr_in6 *)(void *)ifa->ifa_netmask;
#ifdef __KAME__
if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr))
/* Remove the scope from the address */
sin6->sin6_addr.s6_addr[2] =
sin6->sin6_addr.s6_addr[3] = '\0';
#endif
ifa_flags = if_addrflags6(&sin6->sin6_addr, ifp);
if (ifa_flags != -1)
ipv6_handleifa(ctx, RTM_NEWADDR, ifs,
ifa->ifa_name,
&sin6->sin6_addr,
ipv6_prefixlen(&net6->sin6_addr),
ifa_flags);
break;
#endif
}
}
}
struct if_head *
if_discover(struct dhcpcd_ctx *ctx, int argc, char * const *argv)
{
struct ifaddrs *ifaddrs, *ifa;
char *p;
int i;
struct if_head *ifs;
struct interface *ifp;
const char *lease_identifier;
char ifn[IF_NAMESIZE];
#ifdef __linux__
char alias[IF_NAMESIZE];
#endif
#ifdef AF_LINK
const struct sockaddr_dl *sdl;
#ifdef SIOCGIFPRIORITY
struct ifreq ifr;
int s_inet;
#endif
#ifdef IFLR_ACTIVE
struct if_laddrreq iflr;
int s_link;
#endif
#ifdef SIOCGIFPRIORITY
if ((s_inet = socket(PF_INET, SOCK_DGRAM, 0)) == -1)
return NULL;
#endif
#ifdef IFLR_ACTIVE
if ((s_link = socket(PF_LINK, SOCK_DGRAM, 0)) == -1) {
#ifdef SIOCGIFPRIORITY
close(s_inet);
#endif
return NULL;
}
memset(&iflr, 0, sizeof(iflr));
#endif
#elif AF_PACKET
const struct sockaddr_ll *sll;
#endif
if (getifaddrs(&ifaddrs) == -1)
return NULL;
ifs = malloc(sizeof(*ifs));
if (ifs == NULL)
return NULL;
TAILQ_INIT(ifs);
for (ifa = ifaddrs; ifa; ifa = ifa->ifa_next) {
if (ifa->ifa_addr != NULL) {
#ifdef AF_LINK
if (ifa->ifa_addr->sa_family != AF_LINK)
continue;
#elif AF_PACKET
if (ifa->ifa_addr->sa_family != AF_PACKET)
continue;
#endif
}
/* It's possible for an interface to have >1 AF_LINK.
* For our purposes, we use the first one. */
TAILQ_FOREACH(ifp, ifs, next) {
if (strcmp(ifp->name, ifa->ifa_name) == 0)
break;
}
if (ifp)
continue;
lease_identifier = NULL;
if (argc > 0) {
for (i = 0; i < argc; i++) {
int intf_len = strlen(argv[i]);
split_interface_lease(argv[i], &intf_len,
&lease_identifier);
if (intf_len > IF_NAMESIZE)
continue;
strlcpy(ifn, argv[i], intf_len + 1);
#ifdef __linux__
strlcpy(alias, argv[i], intf_len + 1);
/* Check the real interface name */
p = strchr(ifn, ':');
if (p)
*p = '\0';
#endif
if (strcmp(ifn, ifa->ifa_name) == 0)
break;
}
if (i == argc)
continue;
} else {
strlcpy(ifn, ifa->ifa_name, sizeof(ifn));
#ifdef __linux
strlcpy(alias, ifa->ifa_name, sizeof(alias));
#endif
/* -1 means we're discovering against a specific
* interface, but we still need the below rules
* to apply. */
if (argc == -1 && strcmp(argv[0], ifa->ifa_name) != 0)
continue;
}
p = ifn;
for (i = 0; i < ctx->ifdc; i++)
if (!fnmatch(ctx->ifdv[i], p, 0))
break;
if (i < ctx->ifdc)
continue;
for (i = 0; i < ctx->ifac; i++)
if (!fnmatch(ctx->ifav[i], p, 0))
break;
if (ctx->ifac && i == ctx->ifac)
continue;
/* Ensure that the interface name has settled */
if (!dev_initialized(ctx, p))
continue;
/* Don't allow loopback or pointopoint unless explicit */
if (ifa->ifa_flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) {
if ((argc == 0 || argc == -1) &&
ctx->ifac == 0 && !if_hasconf(ctx, p))
continue;
}
if (if_vimaster(p) == 1) {
logger(ctx, argc ? LOG_ERR : LOG_DEBUG,
"%s: is a Virtual Interface Master, skipping", p);
continue;
}
ifp = calloc(1, sizeof(*ifp));
if (ifp == NULL) {
logger(ctx, LOG_ERR, "%s: %m", __func__);
break;
}
ifp->ctx = ctx;
#ifdef __linux__
strlcpy(ifp->alias, alias, sizeof(ifp->alias));
#endif
strlcpy(ifp->name, p, sizeof(ifp->name));
if (lease_identifier) {
strlcpy(ifp->lease_identifier, lease_identifier,
sizeof(ifp->lease_identifier));
}
ifp->flags = ifa->ifa_flags;
ifp->carrier = if_carrier(ifp);
if (ifa->ifa_addr != NULL) {
#ifdef AF_LINK
sdl = (const struct sockaddr_dl *)(void *)ifa->ifa_addr;
#ifdef IFLR_ACTIVE
/* We need to check for active address */
strlcpy(iflr.iflr_name, ifp->name,
sizeof(iflr.iflr_name));
memcpy(&iflr.addr, ifa->ifa_addr,
MIN(ifa->ifa_addr->sa_len, sizeof(iflr.addr)));
iflr.flags = IFLR_PREFIX;
iflr.prefixlen = (unsigned int)sdl->sdl_alen * NBBY;
if (ioctl(s_link, SIOCGLIFADDR, &iflr) == -1 ||
!(iflr.flags & IFLR_ACTIVE))
{
if_free(ifp);
continue;
}
#endif
ifp->index = sdl->sdl_index;
switch(sdl->sdl_type) {
#ifdef IFT_BRIDGE
case IFT_BRIDGE: /* FALLTHROUGH */
#endif
#ifdef IFT_PPP
case IFT_PPP: /* FALLTHROUGH */
#endif
#ifdef IFT_PROPVIRTUAL
case IFT_PROPVIRTUAL: /* FALLTHROUGH */
#endif
#if defined(IFT_BRIDGE) || defined(IFT_PPP) || defined(IFT_PROPVIRTUAL)
/* Don't allow unless explicit */
if ((argc == 0 || argc == -1) &&
ctx->ifac == 0 &&
!if_hasconf(ctx, ifp->name))
{
logger(ifp->ctx, LOG_DEBUG,
"%s: ignoring due to"
" interface type and"
" no config",
ifp->name);
if_free(ifp);
continue;
}
/* FALLTHROUGH */
#endif
#ifdef IFT_L2VLAN
case IFT_L2VLAN: /* FALLTHROUGH */
#endif
#ifdef IFT_L3IPVLAN
case IFT_L3IPVLAN: /* FALLTHROUGH */
#endif
case IFT_ETHER:
ifp->family = ARPHRD_ETHER;
break;
#ifdef IFT_IEEE1394
case IFT_IEEE1394:
ifp->family = ARPHRD_IEEE1394;
break;
#endif
#ifdef IFT_INFINIBAND
case IFT_INFINIBAND:
ifp->family = ARPHRD_INFINIBAND;
break;
#endif
default:
/* Don't allow unless explicit */
if ((argc == 0 || argc == -1) &&
ctx->ifac == 0 &&
!if_hasconf(ctx, ifp->name))
{
if_free(ifp);
continue;
}
logger(ifp->ctx, LOG_WARNING,
"%s: unsupported interface type %.2x",
ifp->name, sdl->sdl_type);
/* Pretend it's ethernet */
ifp->family = ARPHRD_ETHER;
break;
}
ifp->hwlen = sdl->sdl_alen;
#ifndef CLLADDR
# define CLLADDR(s) ((const char *)((s)->sdl_data + (s)->sdl_nlen))
#endif
memcpy(ifp->hwaddr, CLLADDR(sdl), ifp->hwlen);
#elif AF_PACKET
sll = (const struct sockaddr_ll *)(void *)ifa->ifa_addr;
ifp->index = (unsigned int)sll->sll_ifindex;
ifp->family = sll->sll_hatype;
ifp->hwlen = sll->sll_halen;
if (ifp->hwlen != 0)
memcpy(ifp->hwaddr, sll->sll_addr, ifp->hwlen);
#endif
}
#ifdef __linux__
/* PPP addresses on Linux don't have hardware addresses */
else
ifp->index = if_nametoindex(ifp->name);
#endif
/* We only work on ethernet by default */
if (ifp->family != ARPHRD_ETHER) {
if ((argc == 0 || argc == -1) &&
ctx->ifac == 0 && !if_hasconf(ctx, ifp->name))
{
if_free(ifp);
continue;
}
switch (ifp->family) {
case ARPHRD_IEEE1394:
case ARPHRD_INFINIBAND:
#ifdef ARPHRD_LOOPBACK
case ARPHRD_LOOPBACK:
#endif
#ifdef ARPHRD_PPP
case ARPHRD_PPP:
#endif
/* We don't warn for supported families */
break;
/* IFT already checked */
#ifndef AF_LINK
default:
logger(ifp->ctx, LOG_WARNING,
"%s: unsupported interface family %.2x",
ifp->name, ifp->family);
break;
#endif
}
}
/* Handle any platform init for the interface */
if (if_init(ifp) == -1) {
logger(ifp->ctx, LOG_ERR, "%s: if_init: %m", p);
if_free(ifp);
continue;
}
/* Ensure that the MTU is big enough for DHCP */
if (if_getmtu(ifp->name) < MTU_MIN &&
if_setmtu(ifp->name, MTU_MIN) == -1)
{
logger(ifp->ctx, LOG_ERR, "%s: set_mtu: %m", p);
if_free(ifp);
continue;
}
#ifdef SIOCGIFPRIORITY
/* Respect the interface priority */
memset(&ifr, 0, sizeof(ifr));
strlcpy(ifr.ifr_name, ifp->name, sizeof(ifr.ifr_name));
if (ioctl(s_inet, SIOCGIFPRIORITY, &ifr) == 0)
ifp->metric = ifr.ifr_metric;
#else
/* We reserve the 100 range for virtual interfaces, if and when
* we can work them out. */
ifp->metric = 200 + ifp->index;
if (if_getssid(ifp) != -1) {
ifp->wireless = 1;
ifp->metric += 100;
}
#endif
TAILQ_INSERT_TAIL(ifs, ifp, next);
}
if (!ifs) {
logger(ctx, LOG_INFO, "%s: no matching interfaces", __func__);
for (ifa = ifaddrs; ifa; ifa = ifa->ifa_next) {
logger(ctx, LOG_INFO, "%s: considered %s",
__func__, ifa->ifa_name);
}
}
if_learnaddrs1(ctx, ifs, ifaddrs);
freeifaddrs(ifaddrs);
#ifdef SIOCGIFPRIORITY
close(s_inet);
#endif
#ifdef IFLR_ACTIVE
close(s_link);
#endif
return ifs;
}
static struct interface *
if_findindexname(struct if_head *ifaces, unsigned int idx, const char *name)
{
if (ifaces != NULL) {
struct interface *ifp;
TAILQ_FOREACH(ifp, ifaces, next) {
if ((ifp->options == NULL ||
!(ifp->options->options & DHCPCD_PFXDLGONLY)) &&
((name && strcmp(ifp->name, name) == 0) ||
#ifdef __linux__
(name && strcmp(ifp->alias, name) == 0) ||
#endif
(!name && ifp->index == idx)))
return ifp;
}
}
errno = ESRCH;
return NULL;
}
struct interface *
if_find(struct if_head *ifaces, const char *name)
{
return if_findindexname(ifaces, 0, name);
}
struct interface *
if_findindex(struct if_head *ifaces, unsigned int idx)
{
return if_findindexname(ifaces, idx, NULL);
}
int
if_domtu(const char *ifname, short int mtu)
{
int s, r;
struct ifreq ifr;
if ((s = socket(PF_INET, SOCK_DGRAM, 0)) == -1)
return -1;
memset(&ifr, 0, sizeof(ifr));
strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
ifr.ifr_mtu = mtu;
r = ioctl(s, mtu ? SIOCSIFMTU : SIOCGIFMTU, &ifr);
close(s);
if (r == -1)
return -1;
return ifr.ifr_mtu;
}
/* Interface comparer for working out ordering. */
static int
if_cmp(const struct interface *si, const struct interface *ti)
{
#ifdef INET
int r;
#endif
/* Always prefer master interfaces */
if (!(si->options->options & DHCPCD_PFXDLGONLY) &&
ti->options->options & DHCPCD_PFXDLGONLY)
return -1;
if (si->options->options & DHCPCD_PFXDLGONLY &&
!(ti->options->options & DHCPCD_PFXDLGONLY))
return 1;
/* Check carrier status first */
if (si->carrier > ti->carrier)
return -1;
if (si->carrier < ti->carrier)
return 1;
if (D_STATE_RUNNING(si) && !D_STATE_RUNNING(ti))
return -1;
if (!D_STATE_RUNNING(si) && D_STATE_RUNNING(ti))
return 1;
if (RS_STATE_RUNNING(si) && !RS_STATE_RUNNING(ti))
return -1;
if (!RS_STATE_RUNNING(si) && RS_STATE_RUNNING(ti))
return 1;
if (D6_STATE_RUNNING(si) && !D6_STATE_RUNNING(ti))
return -1;
if (!D6_STATE_RUNNING(si) && D6_STATE_RUNNING(ti))
return 1;
#ifdef INET
/* Special attention needed here due to states and IPv4LL. */
if ((r = ipv4_ifcmp(si, ti)) != 0)
return r;
#endif
/* Finally, metric */
if (si->metric < ti->metric)
return -1;
if (si->metric > ti->metric)
return 1;
return 0;
}
/* Sort the interfaces into a preferred order - best first, worst last. */
void
if_sortinterfaces(struct dhcpcd_ctx *ctx)
{
struct if_head sorted;
struct interface *ifp, *ift;
if (ctx->ifaces == NULL ||
(ifp = TAILQ_FIRST(ctx->ifaces)) == NULL ||
TAILQ_NEXT(ifp, next) == NULL)
return;
TAILQ_INIT(&sorted);
TAILQ_REMOVE(ctx->ifaces, ifp, next);
TAILQ_INSERT_HEAD(&sorted, ifp, next);
while ((ifp = TAILQ_FIRST(ctx->ifaces))) {
TAILQ_REMOVE(ctx->ifaces, ifp, next);
TAILQ_FOREACH(ift, &sorted, next) {
if (if_cmp(ifp, ift) == -1) {
TAILQ_INSERT_BEFORE(ift, ifp, next);
break;
}
}
if (ift == NULL)
TAILQ_INSERT_TAIL(&sorted, ifp, next);
}
TAILQ_CONCAT(ctx->ifaces, &sorted, next);
}