#include <machine/rtems-bsd-user-space.h>
/* $OpenBSD: dispatch.c,v 1.31 2004/09/21 04:07:03 david Exp $ */
/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright 2004 Henning Brauer <henning@openbsd.org>
* Copyright (c) 1995, 1996, 1997, 1998, 1999
* The Internet Software Consortium. 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.
* 3. Neither the name of The Internet Software Consortium nor the names
* of its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM 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 INTERNET SOFTWARE CONSORTIUM 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.
*
* This software has been written for the Internet Software Consortium
* by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
* Enterprises. To learn more about the Internet Software Consortium,
* see ``http://www.vix.com/isc''. To learn more about Vixie
* Enterprises, see ``http://www.vix.com''.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "dhcpd.h"
#include "privsep.h"
#include <sys/ioctl.h>
#include <assert.h>
#include <net/if_media.h>
#include <ifaddrs.h>
#include <poll.h>
/* Assert that pointer p is aligned to at least align bytes */
#define assert_aligned(p, align) assert((((uintptr_t)p) & ((align) - 1)) == 0)
static struct protocol *protocols;
static struct timeout *timeouts;
static struct timeout *free_timeouts;
static int interfaces_invalidated;
void (*bootp_packet_handler)(struct interface_info *,
struct dhcp_packet *, int, unsigned int,
struct iaddr, struct hardware *);
static int interface_status(struct interface_info *ifinfo);
/*
* Use getifaddrs() to get a list of all the attached interfaces. For
* each interface that's of type INET and not the loopback interface,
* register that interface with the network I/O software, figure out
* what subnet it's on, and add it to the list of interfaces.
*/
void
discover_interfaces(struct interface_info *iface)
{
struct ifaddrs *ifap, *ifa;
struct ifreq *tif;
if (getifaddrs(&ifap) != 0)
error("getifaddrs failed");
for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) {
if ((ifa->ifa_flags & IFF_LOOPBACK) ||
(ifa->ifa_flags & IFF_POINTOPOINT) ||
(!(ifa->ifa_flags & IFF_UP)))
continue;
if (strcmp(iface->name, ifa->ifa_name))
continue;
/*
* If we have the capability, extract link information
* and record it in a linked list.
*/
if (ifa->ifa_addr->sa_family == AF_LINK) {
struct sockaddr_dl *foo;
/*
* The implementation of getifaddrs should guarantee
* this alignment
*/
assert_aligned(ifa->ifa_addr,
_Alignof(struct sockaddr_dl));
#ifdef __clang__
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wcast-align"
#endif
foo = (struct sockaddr_dl *)ifa->ifa_addr;
#ifdef __clang__
#pragma clang diagnostic pop
#endif
iface->index = foo->sdl_index;
iface->hw_address.hlen = foo->sdl_alen;
iface->hw_address.htype = HTYPE_ETHER; /* XXX */
memcpy(iface->hw_address.haddr,
LLADDR(foo), foo->sdl_alen);
} else if (ifa->ifa_addr->sa_family == AF_INET) {
struct sockaddr_in foo;
struct iaddr addr;
memcpy(&foo, ifa->ifa_addr, sizeof(foo));
if (foo.sin_addr.s_addr == htonl(INADDR_LOOPBACK))
continue;
if (!iface->ifp) {
if ((tif = calloc(1, sizeof(struct ifreq)))
== NULL)
error("no space to remember ifp");
strlcpy(tif->ifr_name, ifa->ifa_name, IFNAMSIZ);
memcpy(&tif->ifr_addr, ifa->ifa_addr,
ifa->ifa_addr->sa_len);
iface->ifp = tif;
iface->primary_address = foo.sin_addr;
}
addr.len = 4;
memcpy(addr.iabuf, &foo.sin_addr.s_addr, addr.len);
}
}
if (!iface->ifp)
error("%s: not found", iface->name);
/* Register the interface... */
if_register_receive(iface);
if_register_send(iface);
add_protocol(iface->name, iface->rfdesc, got_one, iface);
freeifaddrs(ifap);
}
void
reinitialize_interfaces(void)
{
interfaces_invalidated = 1;
}
/*
* Wait for packets to come in using poll(). When a packet comes in,
* call receive_packet to receive the packet and possibly strip hardware
* addressing information from it, and then call through the
* bootp_packet_handler hook to try to do something with it.
*/
void
dispatch(void)
{
int count, live_interfaces, i, to_msec, nfds = 0;
struct protocol *l;
struct pollfd *fds;
time_t howlong;
for (l = protocols; l; l = l->next)
nfds++;
fds = malloc(nfds * sizeof(struct pollfd));
if (fds == NULL)
error("Can't allocate poll structures.");
do {
/*
* Call any expired timeouts, and then if there's still
* a timeout registered, time out the select call then.
*/
another:
if (timeouts) {
struct timeout *t;
if (timeouts->when <= cur_time) {
t = timeouts;
timeouts = timeouts->next;
(*(t->func))(t->what);
t->next = free_timeouts;
free_timeouts = t;
goto another;
}
/*
* Figure timeout in milliseconds, and check for
* potential overflow, so we can cram into an
* int for poll, while not polling with a
* negative timeout and blocking indefinitely.
*/
howlong = timeouts->when - cur_time;
if (howlong > INT_MAX / 1000)
howlong = INT_MAX / 1000;
to_msec = howlong * 1000;
} else
to_msec = -1;
/* Set up the descriptors to be polled. */
live_interfaces = 0;
for (i = 0, l = protocols; l; l = l->next) {
struct interface_info *ip = l->local;
if (ip == NULL || ip->dead)
continue;
fds[i].fd = l->fd;
fds[i].events = POLLIN;
fds[i].revents = 0;
i++;
if (l->handler == got_one)
live_interfaces++;
}
if (live_interfaces == 0)
error("No live interfaces to poll on - exiting.");
/* Wait for a packet or a timeout... XXX */
count = poll(fds, nfds, to_msec);
/* Not likely to be transitory... */
if (count == -1) {
if (errno == EAGAIN || errno == EINTR) {
time(&cur_time);
continue;
} else
error("poll: %m");
}
/* Get the current time... */
time(&cur_time);
i = 0;
for (l = protocols; l; l = l->next) {
struct interface_info *ip;
ip = l->local;
if ((fds[i].revents & (POLLIN | POLLHUP))) {
fds[i].revents = 0;
if (ip && (l->handler != got_one ||
!ip->dead))
(*(l->handler))(l);
if (interfaces_invalidated)
break;
}
i++;
}
interfaces_invalidated = 0;
} while (1);
}
void
got_one(struct protocol *l)
{
struct sockaddr_in from;
struct hardware hfrom;
struct iaddr ifrom;
ssize_t result;
union {
/*
* Packet input buffer. Must be as large as largest
* possible MTU.
*/
unsigned char packbuf[4095];
struct dhcp_packet packet;
} u;
struct interface_info *ip = l->local;
if ((result = receive_packet(ip, u.packbuf, sizeof(u), &from,
&hfrom)) == -1) {
warning("receive_packet failed on %s: %s", ip->name,
strerror(errno));
ip->errors++;
if ((!interface_status(ip)) ||
(ip->noifmedia && ip->errors > 20)) {
/* our interface has gone away. */
warning("Interface %s no longer appears valid.",
ip->name);
ip->dead = 1;
interfaces_invalidated = 1;
close(l->fd);
remove_protocol(l);
free(ip);
}
return;
}
if (result == 0)
return;
if (bootp_packet_handler) {
ifrom.len = 4;
memcpy(ifrom.iabuf, &from.sin_addr, ifrom.len);
(*bootp_packet_handler)(ip, &u.packet, result,
from.sin_port, ifrom, &hfrom);
}
}
int
interface_status(struct interface_info *ifinfo)
{
char *ifname = ifinfo->name;
int ifsock = ifinfo->rfdesc;
struct ifreq ifr;
struct ifmediareq ifmr;
/* get interface flags */
memset(&ifr, 0, sizeof(ifr));
strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
if (ioctl(ifsock, SIOCGIFFLAGS, &ifr) < 0) {
cap_syslog(capsyslog, LOG_ERR, "ioctl(SIOCGIFFLAGS) on %s: %m",
ifname);
goto inactive;
}
/*
* if one of UP and RUNNING flags is dropped,
* the interface is not active.
*/
if ((ifr.ifr_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
goto inactive;
/* Next, check carrier on the interface, if possible */
if (ifinfo->noifmedia)
goto active;
memset(&ifmr, 0, sizeof(ifmr));
strlcpy(ifmr.ifm_name, ifname, sizeof(ifmr.ifm_name));
if (ioctl(ifsock, SIOCGIFMEDIA, (caddr_t)&ifmr) < 0) {
if (errno != EINVAL) {
cap_syslog(capsyslog, LOG_DEBUG,
"ioctl(SIOCGIFMEDIA) on %s: %m", ifname);
ifinfo->noifmedia = 1;
goto active;
}
/*
* EINVAL (or ENOTTY) simply means that the interface
* does not support the SIOCGIFMEDIA ioctl. We regard it alive.
*/
ifinfo->noifmedia = 1;
goto active;
}
if (ifmr.ifm_status & IFM_AVALID) {
switch (ifmr.ifm_active & IFM_NMASK) {
case IFM_ETHER:
case IFM_IEEE80211:
if (ifmr.ifm_status & IFM_ACTIVE)
goto active;
else
goto inactive;
break;
default:
goto inactive;
}
}
inactive:
return (0);
active:
return (1);
}
void
add_timeout(time_t when, void (*where)(void *), void *what)
{
struct timeout *t, *q;
/* See if this timeout supersedes an existing timeout. */
t = NULL;
for (q = timeouts; q; q = q->next) {
if (q->func == where && q->what == what) {
if (t)
t->next = q->next;
else
timeouts = q->next;
break;
}
t = q;
}
/* If we didn't supersede a timeout, allocate a timeout
structure now. */
if (!q) {
if (free_timeouts) {
q = free_timeouts;
free_timeouts = q->next;
q->func = where;
q->what = what;
} else {
q = malloc(sizeof(struct timeout));
if (!q)
error("Can't allocate timeout structure!");
q->func = where;
q->what = what;
}
}
q->when = when;
/* Now sort this timeout into the timeout list. */
/* Beginning of list? */
if (!timeouts || timeouts->when > q->when) {
q->next = timeouts;
timeouts = q;
return;
}
/* Middle of list? */
for (t = timeouts; t->next; t = t->next) {
if (t->next->when > q->when) {
q->next = t->next;
t->next = q;
return;
}
}
/* End of list. */
t->next = q;
q->next = NULL;
}
void
cancel_timeout(void (*where)(void *), void *what)
{
struct timeout *t, *q;
/* Look for this timeout on the list, and unlink it if we find it. */
t = NULL;
for (q = timeouts; q; q = q->next) {
if (q->func == where && q->what == what) {
if (t)
t->next = q->next;
else
timeouts = q->next;
break;
}
t = q;
}
/* If we found the timeout, put it on the free list. */
if (q) {
q->next = free_timeouts;
free_timeouts = q;
}
}
/* Add a protocol to the list of protocols... */
void
add_protocol(const char *name, int fd, void (*handler)(struct protocol *),
void *local)
{
struct protocol *p;
p = malloc(sizeof(*p));
if (!p)
error("can't allocate protocol struct for %s", name);
p->fd = fd;
p->handler = handler;
p->local = local;
p->next = protocols;
protocols = p;
}
void
remove_protocol(struct protocol *proto)
{
struct protocol *p, *next;
for (p = protocols; p; p = next) {
next = p->next;
if (p == proto) {
protocols = p->next;
free(p);
}
}
}
int
interface_link_status(char *ifname)
{
struct ifmediareq ifmr;
int sock;
if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
error("Can't create socket");
memset(&ifmr, 0, sizeof(ifmr));
strlcpy(ifmr.ifm_name, ifname, sizeof(ifmr.ifm_name));
if (ioctl(sock, SIOCGIFMEDIA, (caddr_t)&ifmr) == -1) {
/* EINVAL -> link state unknown. treat as active */
if (errno != EINVAL)
cap_syslog(capsyslog, LOG_DEBUG,
"ioctl(SIOCGIFMEDIA) on %s: %m", ifname);
close(sock);
return (1);
}
close(sock);
if (ifmr.ifm_status & IFM_AVALID) {
switch (ifmr.ifm_active & IFM_NMASK) {
case IFM_ETHER:
case IFM_IEEE80211:
if (ifmr.ifm_status & IFM_ACTIVE)
return (1);
else
return (0);
}
}
return (1);
}
void
interface_set_mtu_unpriv(int privfd, u_int16_t mtu)
{
struct imsg_hdr hdr;
struct buf *buf;
int errs = 0;
hdr.code = IMSG_SET_INTERFACE_MTU;
hdr.len = sizeof(hdr) +
sizeof(u_int16_t);
if ((buf = buf_open(hdr.len)) == NULL)
error("buf_open: %m");
errs += buf_add(buf, &hdr, sizeof(hdr));
errs += buf_add(buf, &mtu, sizeof(mtu));
if (errs)
error("buf_add: %m");
if (buf_close(privfd, buf) == -1)
error("buf_close: %m");
}
void
interface_set_mtu_priv(char *ifname, u_int16_t mtu)
{
struct ifreq ifr;
int sock;
u_int16_t old_mtu;
if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
error("Can't create socket");
memset(&ifr, 0, sizeof(ifr));
old_mtu = 0;
strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
if (ioctl(sock, SIOCGIFMTU, (caddr_t)&ifr) == -1)
warning("SIOCGIFMTU failed (%s): %s", ifname,
strerror(errno));
else
old_mtu = ifr.ifr_mtu;
if (mtu != old_mtu) {
ifr.ifr_mtu = mtu;
if (ioctl(sock, SIOCSIFMTU, &ifr) == -1)
warning("SIOCSIFMTU failed (%d): %s", mtu,
strerror(errno));
}
close(sock);
}
