582 lines
16 KiB
C
582 lines
16 KiB
C
/* dhcpd.c
|
|
|
|
DHCP Server Daemon. */
|
|
|
|
/*
|
|
* Copyright (c) 1996-2000 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 in cooperation with Vixie Enterprises and Nominum, Inc.
|
|
* To learn more about the Internet Software Consortium, see
|
|
* ``http://www.isc.org/''. To learn more about Vixie Enterprises,
|
|
* see ``http://www.vix.com''. To learn more about Nominum, Inc., see
|
|
* ``http://www.nominum.com''.
|
|
*/
|
|
|
|
#ifndef lint
|
|
static char ocopyright[] =
|
|
"$Id: dhcpd.c,v 1.15 2000/04/22 08:18:17 mellon Exp $ Copyright 1995-2000 The Internet Software Consortium.";
|
|
#endif
|
|
|
|
static char copyright[] =
|
|
"Copyright 1995, 1996, 1997, 1998, 1999 The Internet Software Consortium.";
|
|
static char arr [] = "All rights reserved.";
|
|
static char message [] = "Internet Software Consortium DHCP Server";
|
|
static char contrib [] = "\nPlease contribute if you find this software useful.";
|
|
static char url [] = "For info, please visit http://www.isc.org/dhcp-contrib.html\n";
|
|
|
|
#include "dhcpd.h"
|
|
#include "version.h"
|
|
#include <omapip/omapip_p.h>
|
|
|
|
static void usage PROTO ((void));
|
|
|
|
TIME cur_time;
|
|
struct group root_group;
|
|
struct binding_scope global_scope;
|
|
|
|
struct iaddr server_identifier;
|
|
int server_identifier_matched;
|
|
|
|
u_int16_t local_port;
|
|
u_int16_t remote_port;
|
|
|
|
struct in_addr limited_broadcast;
|
|
|
|
/* This is the standard name service updater that is executed whenever a
|
|
lease is committed. Right now it's not following the DHCP-DNS draft
|
|
at all, but as soon as I fix the resolver it should try to. */
|
|
|
|
#if defined (NSUPDATE)
|
|
char std_nsupdate [] = " \n\
|
|
on commit { \n\
|
|
if (not defined (ddns-fwd-name)) { \n\
|
|
set ddns-fwd-name = concat (pick (config-option server.ddns-hostname, \n\
|
|
option host-name), \".\", \n\
|
|
pick (config-option server.ddns-domainname, \n\
|
|
config-option domain-name)); \n\
|
|
if defined (ddns-fwd-name) { \n\
|
|
switch (ns-update (not exists (IN, A, ddns-fwd-name, null), \n\
|
|
add (IN, A, ddns-fwd-name, leased-address, \n\
|
|
lease-time / 2))) { \n\
|
|
default: \n\
|
|
unset ddns-fwd-name; \n\
|
|
break; \n\
|
|
\n\
|
|
case NOERROR: \n\
|
|
set ddns-rev-name = \n\
|
|
concat (binary-to-ascii (10, 8, \".\", \n\
|
|
reverse (1, \n\
|
|
leased-address)), \".\", \n\
|
|
pick (config-option server.ddns-rev-domainname, \n\
|
|
\"in-addr.arpa.\")); \n\
|
|
switch (ns-update (delete (IN, PTR, ddns-rev-name, null), \n\
|
|
add (IN, PTR, ddns-rev-name, ddns-fwd-name, \n\
|
|
lease-time / 2))) \n\
|
|
{ \n\
|
|
default: \n\
|
|
unset ddns-rev-name; \n\
|
|
on release or expiry { \n\
|
|
switch (ns-update (delete (IN, A, ddns-fwd-name, \n\
|
|
leased-address))) { \n\
|
|
case NOERROR: \n\
|
|
unset ddns-fwd-name; \n\
|
|
break; \n\
|
|
} \n\
|
|
on release or expiry; \n\
|
|
} \n\
|
|
break; \n\
|
|
\n\
|
|
case NOERROR: \n\
|
|
on release or expiry { \n\
|
|
switch (ns-update (delete (IN, PTR, ddns-rev-name, null))) { \n\
|
|
case NOERROR: \n\
|
|
unset ddns-rev-name; \n\
|
|
break; \n\
|
|
} \n\
|
|
switch (ns-update (delete (IN, A, ddns-fwd-name, \n\
|
|
leased-address))) { \n\
|
|
case NOERROR: \n\
|
|
unset ddns-fwd-name; \n\
|
|
break; \n\
|
|
} \n\
|
|
on release or expiry; \n\
|
|
} \n\
|
|
} \n\
|
|
} \n\
|
|
} \n\
|
|
} \n\
|
|
}";
|
|
#endif /* NSUPDATE */
|
|
|
|
const char *path_dhcpd_conf = _PATH_DHCPD_CONF;
|
|
const char *path_dhcpd_db = _PATH_DHCPD_DB;
|
|
const char *path_dhcpd_pid = _PATH_DHCPD_PID;
|
|
|
|
int dhcp_max_agent_option_packet_length = DHCP_MTU_MAX;
|
|
|
|
int main (argc, argv, envp)
|
|
int argc;
|
|
char **argv, **envp;
|
|
{
|
|
int i, status;
|
|
struct servent *ent;
|
|
char *s;
|
|
int cftest = 0;
|
|
int lftest = 0;
|
|
#ifndef DEBUG
|
|
int pidfilewritten = 0;
|
|
int pid;
|
|
char pbuf [20];
|
|
int daemon = 1;
|
|
#endif
|
|
int quiet = 0;
|
|
char *server = (char *)0;
|
|
isc_result_t result;
|
|
omapi_object_t *listener;
|
|
unsigned seed;
|
|
struct interface_info *ip;
|
|
struct data_string fname;
|
|
struct option_cache *oc;
|
|
struct option_state *options = (struct option_state *)0;
|
|
struct parse *parse;
|
|
int lose;
|
|
|
|
/* Initially, log errors to stderr as well as to syslogd. */
|
|
#ifdef SYSLOG_4_2
|
|
openlog ("dhcpd", LOG_NDELAY);
|
|
log_priority = DHCPD_LOG_FACILITY;
|
|
#else
|
|
openlog ("dhcpd", LOG_NDELAY, DHCPD_LOG_FACILITY);
|
|
#endif
|
|
|
|
for (i = 1; i < argc; i++) {
|
|
if (!strcmp (argv [i], "-p")) {
|
|
if (++i == argc)
|
|
usage ();
|
|
for (s = argv [i]; *s; s++)
|
|
if (!isdigit (*s))
|
|
log_fatal ("%s: not a valid UDP port",
|
|
argv [i]);
|
|
status = atoi (argv [i]);
|
|
if (status < 1 || status > 65535)
|
|
log_fatal ("%s: not a valid UDP port",
|
|
argv [i]);
|
|
local_port = htons (status);
|
|
log_debug ("binding to user-specified port %d",
|
|
ntohs (local_port));
|
|
} else if (!strcmp (argv [i], "-f")) {
|
|
#ifndef DEBUG
|
|
daemon = 0;
|
|
#endif
|
|
} else if (!strcmp (argv [i], "-d")) {
|
|
#ifndef DEBUG
|
|
daemon = 0;
|
|
#endif
|
|
log_perror = -1;
|
|
} else if (!strcmp (argv [i], "-s")) {
|
|
if (++i == argc)
|
|
usage ();
|
|
server = argv [i];
|
|
} else if (!strcmp (argv [i], "-cf")) {
|
|
if (++i == argc)
|
|
usage ();
|
|
path_dhcpd_conf = argv [i];
|
|
} else if (!strcmp (argv [i], "-lf")) {
|
|
if (++i == argc)
|
|
usage ();
|
|
path_dhcpd_db = argv [i];
|
|
} else if (!strcmp (argv [i], "-pf")) {
|
|
if (++i == argc)
|
|
usage ();
|
|
path_dhcpd_pid = argv [i];
|
|
} else if (!strcmp (argv [i], "-t")) {
|
|
/* test configurations only */
|
|
#ifndef DEBUG
|
|
daemon = 0;
|
|
#endif
|
|
cftest = 1;
|
|
log_perror = -1;
|
|
} else if (!strcmp (argv [i], "-T")) {
|
|
/* test configurations and lease file only */
|
|
#ifndef DEBUG
|
|
daemon = 0;
|
|
#endif
|
|
cftest = 1;
|
|
lftest = 1;
|
|
log_perror = -1;
|
|
} else if (!strcmp (argv [i], "-q")) {
|
|
quiet = 1;
|
|
quiet_interface_discovery = 1;
|
|
} else if (argv [i][0] == '-') {
|
|
usage ();
|
|
} else {
|
|
struct interface_info *tmp =
|
|
((struct interface_info *)
|
|
dmalloc (sizeof *tmp, MDL));
|
|
if (!tmp)
|
|
log_fatal ("Insufficient memory to %s %s",
|
|
"record interface", argv [i]);
|
|
memset (tmp, 0, sizeof *tmp);
|
|
strcpy (tmp -> name, argv [i]);
|
|
tmp -> next = interfaces;
|
|
tmp -> flags = INTERFACE_REQUESTED;
|
|
interfaces = tmp;
|
|
}
|
|
}
|
|
|
|
if (!quiet) {
|
|
log_info ("%s %s", message, DHCP_VERSION);
|
|
log_info (copyright);
|
|
log_info (arr);
|
|
log_info (contrib);
|
|
log_info (url);
|
|
} else {
|
|
quiet = 0;
|
|
log_perror = 0;
|
|
}
|
|
|
|
/* Default to the DHCP/BOOTP port. */
|
|
if (!local_port)
|
|
{
|
|
ent = getservbyname ("dhcp", "udp");
|
|
if (!ent)
|
|
local_port = htons (67);
|
|
else
|
|
local_port = ent -> s_port;
|
|
#ifndef __CYGWIN32__ /* XXX */
|
|
endservent ();
|
|
#endif
|
|
}
|
|
|
|
remote_port = htons (ntohs (local_port) + 1);
|
|
|
|
if (server) {
|
|
if (!inet_aton (server, &limited_broadcast)) {
|
|
struct hostent *he;
|
|
he = gethostbyname (server);
|
|
if (he) {
|
|
memcpy (&limited_broadcast,
|
|
he -> h_addr_list [0],
|
|
sizeof limited_broadcast);
|
|
} else
|
|
limited_broadcast.s_addr = INADDR_BROADCAST;
|
|
}
|
|
} else {
|
|
limited_broadcast.s_addr = INADDR_BROADCAST;
|
|
}
|
|
|
|
/* Get the current time... */
|
|
GET_TIME (&cur_time);
|
|
|
|
/* Set up the client classification system. */
|
|
classification_setup ();
|
|
|
|
/* Initialize the omapi system. */
|
|
result = omapi_init ();
|
|
if (result != ISC_R_SUCCESS)
|
|
log_fatal ("Can't initialize OMAPI: %s\n",
|
|
isc_result_totext (result));
|
|
|
|
/* Set up the OMAPI wrappers for various server database internal
|
|
objects. */
|
|
dhcp_db_objects_setup ();
|
|
|
|
/* Set up the initial dhcp option universe. */
|
|
initialize_common_option_spaces ();
|
|
initialize_server_option_spaces ();
|
|
|
|
root_group.authoritative = 0;
|
|
|
|
#if defined (NSUPDATE)
|
|
/* Set up the standard name service updater routine. */
|
|
parse = (struct parse *)0;
|
|
status = new_parse (&parse, -1,
|
|
std_nsupdate, (sizeof std_nsupdate) - 1,
|
|
"standard name service update routine");
|
|
if (status != ISC_R_SUCCESS)
|
|
log_fatal ("can't parse standard name service updater!");
|
|
|
|
if (!(parse_executable_statements
|
|
(&root_group.statements, parse, &lose, context_any))) {
|
|
end_parse (&parse);
|
|
log_fatal ("can't parse standard name service updater!");
|
|
}
|
|
end_parse (&parse);
|
|
#endif
|
|
|
|
/* Read the dhcpd.conf file... */
|
|
if (readconf () != ISC_R_SUCCESS)
|
|
log_fatal ("Configuration file errors encountered -- exiting");
|
|
|
|
/* test option should cause an early exit */
|
|
if (cftest && !lftest)
|
|
exit(0);
|
|
|
|
/* Now try to get the lease file name. */
|
|
option_state_allocate (&options, MDL);
|
|
|
|
execute_statements_in_scope ((struct packet *)0,
|
|
(struct lease *)0,
|
|
(struct option_state *)0,
|
|
options, &global_scope,
|
|
&root_group,
|
|
(struct group *)0);
|
|
memset (&fname, 0, sizeof fname);
|
|
oc = lookup_option (&server_universe, options, SV_LEASE_FILE_NAME);
|
|
if (oc &&
|
|
evaluate_option_cache (&fname, (struct packet *)0,
|
|
(struct lease *)0, options,
|
|
(struct option_state *)0,
|
|
&global_scope, oc, MDL)) {
|
|
s = dmalloc (fname.len + 1, MDL);
|
|
if (!s)
|
|
log_fatal ("no memory for lease db filename.");
|
|
memcpy (s, fname.data, fname.len);
|
|
s [fname.len] = 0;
|
|
data_string_forget (&fname, MDL);
|
|
path_dhcpd_db = s;
|
|
}
|
|
|
|
oc = lookup_option (&server_universe, options, SV_PID_FILE_NAME);
|
|
if (oc &&
|
|
evaluate_option_cache (&fname, (struct packet *)0,
|
|
(struct lease *)0, options,
|
|
(struct option_state *)0,
|
|
&global_scope, oc, MDL)) {
|
|
s = dmalloc (fname.len + 1, MDL);
|
|
if (!s)
|
|
log_fatal ("no memory for lease db filename.");
|
|
memcpy (s, fname.data, fname.len);
|
|
s [fname.len] = 0;
|
|
data_string_forget (&fname, MDL);
|
|
path_dhcpd_pid = s;
|
|
}
|
|
|
|
/* Don't need the options anymore. */
|
|
option_state_dereference (&options, MDL);
|
|
|
|
/* Start up the database... */
|
|
db_startup (lftest);
|
|
|
|
if (lftest)
|
|
exit (0);
|
|
|
|
/* Discover all the network interfaces and initialize them. */
|
|
discover_interfaces (DISCOVER_SERVER);
|
|
|
|
/* Make up a seed for the random number generator from current
|
|
time plus the sum of the last four bytes of each
|
|
interface's hardware address interpreted as an integer.
|
|
Not much entropy, but we're booting, so we're not likely to
|
|
find anything better. */
|
|
seed = 0;
|
|
for (ip = interfaces; ip; ip = ip -> next) {
|
|
int junk;
|
|
memcpy (&junk,
|
|
&ip -> hw_address.hbuf [ip -> hw_address.hlen -
|
|
sizeof seed], sizeof seed);
|
|
seed += junk;
|
|
}
|
|
srandom (seed + cur_time);
|
|
|
|
/* Initialize icmp support... */
|
|
icmp_startup (1, lease_pinged);
|
|
|
|
/* Start up a listener for the object management API protocol. */
|
|
listener = (omapi_object_t *)0;
|
|
result = omapi_generic_new (&listener, MDL);
|
|
if (result != ISC_R_SUCCESS)
|
|
log_fatal ("Can't allocate new generic object: %s\n",
|
|
isc_result_totext (result));
|
|
result = omapi_protocol_listen (listener,
|
|
OMAPI_PROTOCOL_PORT, 1);
|
|
if (result != ISC_R_SUCCESS)
|
|
log_fatal ("Can't start OMAPI protocol: %s",
|
|
isc_result_totext (result));
|
|
|
|
#ifndef DEBUG
|
|
if (daemon) {
|
|
/* First part of becoming a daemon... */
|
|
if ((pid = fork ()) < 0)
|
|
log_fatal ("Can't fork daemon: %m");
|
|
else if (pid)
|
|
exit (0);
|
|
}
|
|
|
|
/* Read previous pid file. */
|
|
if ((i = open (path_dhcpd_pid, O_RDONLY)) >= 0) {
|
|
status = read (i, pbuf, (sizeof pbuf) - 1);
|
|
close (i);
|
|
pbuf [status] = 0;
|
|
pid = atoi (pbuf);
|
|
|
|
/* If the previous server process is not still running,
|
|
write a new pid file immediately. */
|
|
if (pid && (pid == getpid() || kill (pid, 0) < 0)) {
|
|
unlink (path_dhcpd_pid);
|
|
if ((i = open (path_dhcpd_pid,
|
|
O_WRONLY | O_CREAT, 0640)) >= 0) {
|
|
sprintf (pbuf, "%d\n", (int)getpid ());
|
|
write (i, pbuf, strlen (pbuf));
|
|
close (i);
|
|
pidfilewritten = 1;
|
|
}
|
|
} else
|
|
log_fatal ("There's already a DHCP server running.\n");
|
|
}
|
|
|
|
/* If we were requested to log to stdout on the command line,
|
|
keep doing so; otherwise, stop. */
|
|
if (log_perror == -1)
|
|
log_perror = 1;
|
|
else
|
|
log_perror = 0;
|
|
|
|
if (daemon) {
|
|
/* Become session leader and get pid... */
|
|
close (0);
|
|
close (1);
|
|
close (2);
|
|
pid = setsid ();
|
|
}
|
|
|
|
/* If we didn't write the pid file earlier because we found a
|
|
process running the logged pid, but we made it to here,
|
|
meaning nothing is listening on the bootp port, then write
|
|
the pid file out - what's in it now is bogus anyway. */
|
|
if (!pidfilewritten) {
|
|
unlink (path_dhcpd_pid);
|
|
if ((i = open (path_dhcpd_pid,
|
|
O_WRONLY | O_CREAT, 0640)) >= 0) {
|
|
sprintf (pbuf, "%d\n", (int)getpid ());
|
|
write (i, pbuf, strlen (pbuf));
|
|
close (i);
|
|
pidfilewritten = 1;
|
|
}
|
|
}
|
|
#endif /* !DEBUG */
|
|
|
|
/* Set up the bootp packet handler... */
|
|
bootp_packet_handler = do_packet;
|
|
|
|
#if defined (DEBUG_MEMORY_LEAKAGE) || defined (DEBUG_MALLOC_POOL)
|
|
dmalloc_cutoff_generation = dmalloc_generation;
|
|
dmalloc_longterm = dmalloc_outstanding;
|
|
dmalloc_outstanding = 0;
|
|
#endif
|
|
|
|
/* Receive packets and dispatch them... */
|
|
dispatch ();
|
|
|
|
/* Not reached */
|
|
return 0;
|
|
}
|
|
|
|
/* Print usage message. */
|
|
|
|
static void usage ()
|
|
{
|
|
log_info (message);
|
|
log_info (copyright);
|
|
log_info (arr);
|
|
|
|
log_fatal ("Usage: dhcpd [-p <UDP port #>] [-d] [-f]%s%s",
|
|
"\n [-cf config-file] [-lf lease-file]",
|
|
"\n [-t] [-T] [-s server] [if0 [...ifN]]");
|
|
}
|
|
|
|
void lease_pinged (from, packet, length)
|
|
struct iaddr from;
|
|
u_int8_t *packet;
|
|
int length;
|
|
{
|
|
struct lease *lp;
|
|
|
|
/* Don't try to look up a pinged lease if we aren't trying to
|
|
ping one - otherwise somebody could easily make us churn by
|
|
just forging repeated ICMP EchoReply packets for us to look
|
|
up. */
|
|
if (!outstanding_pings)
|
|
return;
|
|
|
|
lp = find_lease_by_ip_addr (from);
|
|
|
|
if (!lp) {
|
|
log_info ("unexpected ICMP Echo Reply from %s", piaddr (from));
|
|
return;
|
|
}
|
|
|
|
if (!lp -> state) {
|
|
log_error ("ICMP Echo Reply for %s late or spurious.\n",
|
|
piaddr (from));
|
|
return;
|
|
}
|
|
|
|
if (lp -> ends > cur_time) {
|
|
log_error ("ICMP Echo reply while lease %s valid\n",
|
|
piaddr (from));
|
|
}
|
|
|
|
/* At this point it looks like we pinged a lease and got a
|
|
response, which shouldn't have happened. */
|
|
data_string_forget (&lp -> state -> parameter_request_list, MDL);
|
|
free_lease_state (lp -> state, MDL);
|
|
lp -> state = (struct lease_state *)0;
|
|
|
|
abandon_lease (lp, "pinged before offer");
|
|
cancel_timeout (lease_ping_timeout, lp);
|
|
--outstanding_pings;
|
|
}
|
|
|
|
void lease_ping_timeout (vlp)
|
|
void *vlp;
|
|
{
|
|
struct lease *lp = vlp;
|
|
|
|
#if defined (DEBUG_MEMORY_LEAKAGE)
|
|
unsigned long previous_outstanding = dmalloc_outstanding;
|
|
#endif
|
|
|
|
--outstanding_pings;
|
|
dhcp_reply (lp);
|
|
|
|
#if defined (DEBUG_MEMORY_LEAKAGE)
|
|
log_info ("generation %ld: %ld new, %ld outstanding, %ld long-term",
|
|
dmalloc_generation,
|
|
dmalloc_outstanding - previous_outstanding,
|
|
dmalloc_outstanding, dmalloc_longterm);
|
|
#endif
|
|
#if defined (DEBUG_MEMORY_LEAKAGE) || defined (DEBUG_MALLOC_POOL)
|
|
dmalloc_dump_outstanding ();
|
|
#endif
|
|
}
|