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NetBSD/usr.sbin/dhcp/client/dhclient.c

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/* dhclient.c
DHCP Client. */
/*
* Copyright (c) 1995-2000 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 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 code is based on the original client state machine that was
* written by Elliot Poger. The code has been extensively hacked on
* by Ted Lemon since then, so any mistakes you find are probably his
* fault and not Elliot's.
*/
#ifndef lint
static char ocopyright[] =
"$Id: dhclient.c,v 1.32 2000/09/04 23:19:30 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998, 1999 Internet Software Consortium. All rights reserved.\n";
#endif /* not lint */
#include "dhcpd.h"
#include "version.h"
TIME cur_time;
TIME default_lease_time = 43200; /* 12 hours... */
TIME max_lease_time = 86400; /* 24 hours... */
const char *path_dhclient_conf = _PATH_DHCLIENT_CONF;
const char *path_dhclient_db = _PATH_DHCLIENT_DB;
const char *path_dhclient_pid = _PATH_DHCLIENT_PID;
int dhcp_max_agent_option_packet_length = 0;
int interfaces_requested = 0;
struct iaddr iaddr_broadcast = { 4, { 255, 255, 255, 255 } };
struct iaddr iaddr_any = { 4, { 0, 0, 0, 0 } };
struct in_addr inaddr_any;
struct sockaddr_in sockaddr_broadcast;
struct in_addr giaddr;
/* ASSERT_STATE() does nothing now; it used to be
assert (state_is == state_shouldbe). */
#define ASSERT_STATE(state_is, state_shouldbe) {}
static char copyright[] = "Copyright 1995-2000 Internet Software Consortium.";
static char arr [] = "All rights reserved.";
static char message [] = "Internet Software Consortium DHCP Client";
static char url [] = "For info, please visit http://www.isc.org/products/DHCP";
u_int16_t local_port;
u_int16_t remote_port;
int no_daemon;
int save_scripts;
static void usage PROTO ((void));
void do_release(struct client_state *);
int main (argc, argv, envp)
int argc;
char **argv, **envp;
{
int i;
struct servent *ent;
struct interface_info *ip;
struct client_state *client;
unsigned seed;
int quiet = 0;
char *server = (char *)0;
char *relay = (char *)0;
isc_result_t status;
int release_mode = 0;
omapi_object_t *listener;
isc_result_t result;
int persist = 0;
int omapi_port;
int no_dhclient_conf = 0;
int no_dhclient_db = 0;
int no_dhclient_pid = 0;
char *s;
#ifdef SYSLOG_4_2
openlog ("dhclient", LOG_NDELAY);
log_priority = LOG_DAEMON;
#else
openlog ("dhclient", LOG_NDELAY, LOG_DAEMON);
#endif
#if !(defined (DEBUG) || defined (SYSLOG_4_2) || defined (__CYGWIN32__))
setlogmask (LOG_UPTO (LOG_INFO));
#endif
/* Set up the OMAPI. */
status = omapi_init ();
if (status != ISC_R_SUCCESS)
log_fatal ("Can't initialize OMAPI: %s",
isc_result_totext (status));
/* Set up the OMAPI wrappers for various server database internal
objects. */
dhcp_common_objects_setup ();
dhcp_interface_discovery_hook = dhclient_interface_discovery_hook;
dhcp_interface_shutdown_hook = dhclient_interface_shutdown_hook;
for (i = 1; i < argc; i++) {
if (!strcmp (argv [i], "-r")) {
release_mode = 1;
no_daemon = 1;
} else if (!strcmp (argv [i], "-p")) {
if (++i == argc)
usage ();
local_port = htons (atoi (argv [i]));
log_debug ("binding to user-specified port %d",
ntohs (local_port));
} else if (!strcmp (argv [i], "-d")) {
no_daemon = 1;
} else if (!strcmp (argv [i], "-D")) {
save_scripts = 1;
} else if (!strcmp (argv [i], "-pf")) {
if (++i == argc)
usage ();
path_dhclient_pid = argv [i];
no_dhclient_pid = 1;
} else if (!strcmp (argv [i], "-cf")) {
if (++i == argc)
usage ();
path_dhclient_conf = argv [i];
no_dhclient_conf = 1;
} else if (!strcmp (argv [i], "-lf")) {
if (++i == argc)
usage ();
path_dhclient_db = argv [i];
no_dhclient_db = 1;
} else if (!strcmp (argv [i], "-q")) {
quiet = 1;
quiet_interface_discovery = 1;
} else if (!strcmp (argv [i], "-s")) {
if (++i == argc)
usage ();
server = argv [i];
} else if (!strcmp (argv [i], "-g")) {
if (++i == argc)
usage ();
relay = argv [i];
} else if (!strcmp (argv [i], "-n")) {
/* do not start up any interfaces */
interfaces_requested = 1;
} else if (!strcmp (argv [i], "-w")) {
/* do not exit if there are no broadcast interfaces. */
persist = 1;
} else if (argv [i][0] == '-') {
usage ();
} else {
struct interface_info *tmp = (struct interface_info *)0;
status = interface_allocate (&tmp, MDL);
if (status != ISC_R_SUCCESS)
log_fatal ("Can't record interface %s:%s",
argv [i], isc_result_totext (status));
if (strlen (argv [i]) > sizeof tmp -> name)
log_fatal ("%s: interface name too long (max %d)",
argv [i], strlen (argv [i]));
strcpy (tmp -> name, argv [i]);
if (interfaces) {
interface_reference (&tmp -> next,
interfaces, MDL);
interface_dereference (&interfaces, MDL);
}
interface_reference (&interfaces, tmp, MDL);
tmp -> flags = INTERFACE_REQUESTED;
interfaces_requested = 1;
}
}
if (!no_dhclient_conf && (s = getenv ("PATH_DHCLIENT_CONF"))) {
path_dhclient_conf = s;
}
if (!no_dhclient_db && (s = getenv ("PATH_DHCLIENT_DB"))) {
path_dhclient_db = s;
}
if (!no_dhclient_pid && (s = getenv ("PATH_DHCLIENT_PID"))) {
path_dhclient_pid = s;
}
/* first kill of any currently running client */
if (release_mode) {
/* XXX inelegant hack to prove concept */
char command[1024];
#if !defined (NO_SNPRINTF)
snprintf (command, 1024, "kill `cat %s`", path_dhclient_pid);
#else
sprintf (command, "kill `cat %s`", path_dhclient_pid);
#endif
system (command);
}
if (!quiet) {
log_info ("%s %s", message, DHCP_VERSION);
log_info (copyright);
log_info (arr);
log_info (url);
} else
log_perror = 0;
/* If we're given a relay agent address to insert, for testing
purposes, figure out what it is. */
if (relay) {
if (!inet_aton (relay, &giaddr)) {
struct hostent *he;
he = gethostbyname (relay);
if (he) {
memcpy (&giaddr, he -> h_addr_list [0],
sizeof giaddr);
} else {
log_fatal ("%s: no such host", relay);
}
}
}
/* Default to the DHCP/BOOTP port. */
if (!local_port) {
if (relay && giaddr.s_addr != INADDR_LOOPBACK) {
local_port = 67;
} else {
ent = getservbyname ("dhcpc", "udp");
if (!ent)
local_port = htons (68);
else
local_port = ent -> s_port;
#ifndef __CYGWIN32__
endservent ();
#endif
}
}
/* If we're faking a relay agent, and we're not using loopback,
use the server port, not the client port. */
if (relay && giaddr.s_addr != INADDR_LOOPBACK)
remote_port = 67;
else
remote_port = htons (ntohs (local_port) - 1); /* XXX */
/* Get the current time... */
GET_TIME (&cur_time);
sockaddr_broadcast.sin_family = AF_INET;
sockaddr_broadcast.sin_port = remote_port;
if (server) {
if (!inet_aton (server, &sockaddr_broadcast.sin_addr)) {
struct hostent *he;
he = gethostbyname (server);
if (he) {
memcpy (&sockaddr_broadcast.sin_addr,
he -> h_addr_list [0],
sizeof sockaddr_broadcast.sin_addr);
} else
sockaddr_broadcast.sin_addr.s_addr =
INADDR_BROADCAST;
}
} else {
sockaddr_broadcast.sin_addr.s_addr = INADDR_BROADCAST;
}
inaddr_any.s_addr = INADDR_ANY;
/* Discover all the network interfaces. */
discover_interfaces (DISCOVER_UNCONFIGURED);
/* Parse the dhclient.conf file. */
read_client_conf ();
/* Parse the lease database. */
read_client_leases ();
/* Rewrite the lease database... */
rewrite_client_leases ();
/* XXX */
/* config_counter(&snd_counter, &rcv_counter); */
/* If no broadcast interfaces were discovered, call the script
and tell it so. */
if (!interfaces) {
/* Call dhclient-script with the NBI flag, in case somebody
cares. */
script_init ((struct client_state *)0, "NBI",
(struct string_list *)0);
script_go ((struct client_state *)0);
/* If we haven't been asked to persist, waiting for new
interfaces, then just exit. */
if (!persist) {
/* Nothing more to do. */
log_info ("No broadcast interfaces found - exiting.");
exit (0);
}
} else if (!release_mode) {
/* Call the script with the list of interfaces. */
for (ip = interfaces; ip; ip = ip -> next) {
/* If interfaces were specified, don't configure
interfaces that weren't specified! */
if (interfaces_requested &&
((ip -> flags & (INTERFACE_REQUESTED |
INTERFACE_AUTOMATIC)) !=
INTERFACE_REQUESTED))
continue;
script_init (ip -> client,
"PREINIT", (struct string_list *)0);
if (ip -> client -> alias)
script_write_params (ip -> client, "alias_",
ip -> client -> alias);
script_go (ip -> client);
}
}
/* At this point, all the interfaces that the script thinks
are relevant should be running, so now we once again call
discover_interfaces(), and this time ask it to actually set
up the interfaces. */
discover_interfaces (interfaces_requested
? DISCOVER_REQUESTED
: DISCOVER_RUNNING);
/* 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);
/* Start a configuration state machine for each interface. */
for (ip = interfaces; ip; ip = ip -> next) {
ip -> flags |= INTERFACE_RUNNING;
for (client = ip -> client; client; client = client -> next) {
if (release_mode)
do_release (client);
else {
client -> state = S_INIT;
/* Set up a timeout to start the initialization
process. */
add_timeout (cur_time + random () % 5,
state_reboot, client, 0, 0);
}
}
}
if (release_mode)
return 0;
/* Start up a listener for the object management API protocol. */
if (top_level_config.omapi_port != -1) {
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,
(unsigned)
top_level_config.omapi_port,
1);
if (result != ISC_R_SUCCESS)
log_fatal ("Can't start OMAPI protocol: %s",
isc_result_totext (result));
}
/* Set up the bootp packet handler... */
bootp_packet_handler = do_packet;
/* Start dispatching packets and timeouts... */
dispatch ();
/*NOTREACHED*/
return 0;
}
static void usage ()
{
log_error ("Usage: dhclient [-d] [-D] [-q] [-p <port>] %s",
"[-s server]");
log_error (" [-lf lease-file] [-pf pid-file]%s",
"[-cf config-file] [interface]");
}
isc_result_t find_class (struct class **c,
const char *s, const char *file, int line)
{
return 0;
}
int check_collection (packet, lease, collection)
struct packet *packet;
struct lease *lease;
struct collection *collection;
{
return 0;
}
void classify (packet, class)
struct packet *packet;
struct class *class;
{
}
int unbill_class (lease, class)
struct lease *lease;
struct class *class;
{
return 0;
}
int find_subnet (struct subnet **sp,
struct iaddr addr, const char *file, int line)
{
return 0;
}
/* Individual States:
*
* Each routine is called from the dhclient_state_machine() in one of
* these conditions:
* -> entering INIT state
* -> recvpacket_flag == 0: timeout in this state
* -> otherwise: received a packet in this state
*
* Return conditions as handled by dhclient_state_machine():
* Returns 1, sendpacket_flag = 1: send packet, reset timer.
* Returns 1, sendpacket_flag = 0: just reset the timer (wait for a milestone).
* Returns 0: finish the nap which was interrupted for no good reason.
*
* Several per-interface variables are used to keep track of the process:
* active_lease: the lease that is being used on the interface
* (null pointer if not configured yet).
* offered_leases: leases corresponding to DHCPOFFER messages that have
* been sent to us by DHCP servers.
* acked_leases: leases corresponding to DHCPACK messages that have been
* sent to us by DHCP servers.
* sendpacket: DHCP packet we're trying to send.
* destination: IP address to send sendpacket to
* In addition, there are several relevant per-lease variables.
* T1_expiry, T2_expiry, lease_expiry: lease milestones
* In the active lease, these control the process of renewing the lease;
* In leases on the acked_leases list, this simply determines when we
* can no longer legitimately use the lease.
*/
void state_reboot (cpp)
void *cpp;
{
struct client_state *client = cpp;
/* If we don't remember an active lease, go straight to INIT. */
if (!client -> active ||
client -> active -> is_bootp) {
state_init (client);
return;
}
/* We are in the rebooting state. */
client -> state = S_REBOOTING;
/* make_request doesn't initialize xid because it normally comes
from the DHCPDISCOVER, but we haven't sent a DHCPDISCOVER,
so pick an xid now. */
client -> xid = random ();
/* Make a DHCPREQUEST packet, and set appropriate per-interface
flags. */
make_request (client, client -> active);
client -> destination = iaddr_broadcast;
client -> first_sending = cur_time;
client -> interval = client -> config -> initial_interval;
/* Zap the medium list... */
client -> medium = (struct string_list *)0;
/* Send out the first DHCPREQUEST packet. */
send_request (client);
}
/* Called when a lease has completely expired and we've been unable to
renew it. */
void state_init (cpp)
void *cpp;
{
struct client_state *client = cpp;
ASSERT_STATE(state, S_INIT);
/* Make a DHCPDISCOVER packet, and set appropriate per-interface
flags. */
make_discover (client, client -> active);
client -> xid = client -> packet.xid;
client -> destination = iaddr_broadcast;
client -> state = S_SELECTING;
client -> first_sending = cur_time;
client -> interval = client -> config -> initial_interval;
/* Add an immediate timeout to cause the first DHCPDISCOVER packet
to go out. */
send_discover (client);
}
/* state_selecting is called when one or more DHCPOFFER packets have been
received and a configurable period of time has passed. */
void state_selecting (cpp)
void *cpp;
{
struct client_state *client = cpp;
struct client_lease *lp, *next, *picked;
ASSERT_STATE(state, S_SELECTING);
/* Cancel state_selecting and send_discover timeouts, since either
one could have got us here. */
cancel_timeout (state_selecting, client);
cancel_timeout (send_discover, client);
/* We have received one or more DHCPOFFER packets. Currently,
the only criterion by which we judge leases is whether or
not we get a response when we arp for them. */
picked = (struct client_lease *)0;
for (lp = client -> offered_leases; lp; lp = next) {
next = lp -> next;
/* Check to see if we got an ARPREPLY for the address
in this particular lease. */
if (!picked) {
picked = lp;
picked -> next = (struct client_lease *)0;
} else {
freeit:
destroy_client_lease (lp);
}
}
client -> offered_leases = (struct client_lease *)0;
/* If we just tossed all the leases we were offered, go back
to square one. */
if (!picked) {
client -> state = S_INIT;
state_init (client);
return;
}
/* If it was a BOOTREPLY, we can just take the address right now. */
if (picked -> is_bootp) {
client -> new = picked;
/* Make up some lease expiry times
XXX these should be configurable. */
client -> new -> expiry = cur_time + 12000;
client -> new -> renewal += cur_time + 8000;
client -> new -> rebind += cur_time + 10000;
client -> state = S_REQUESTING;
/* Bind to the address we received. */
bind_lease (client);
return;
}
/* Go to the REQUESTING state. */
client -> destination = iaddr_broadcast;
client -> state = S_REQUESTING;
client -> first_sending = cur_time;
client -> interval = client -> config -> initial_interval;
/* Make a DHCPREQUEST packet from the lease we picked. */
make_request (client, picked);
client -> xid = client -> packet.xid;
/* Toss the lease we picked - we'll get it back in a DHCPACK. */
destroy_client_lease (picked);
/* Add an immediate timeout to send the first DHCPREQUEST packet. */
send_request (client);
}
/* state_requesting is called when we receive a DHCPACK message after
having sent out one or more DHCPREQUEST packets. */
void dhcpack (packet)
struct packet *packet;
{
struct interface_info *ip = packet -> interface;
struct client_state *client;
struct client_lease *lease;
struct option_cache *oc;
struct data_string ds;
int i;
/* If we're not receptive to an offer right now, or if the offer
has an unrecognizable transaction id, then just drop it. */
for (client = ip -> client; client; client = client -> next) {
if (client -> xid == packet -> raw -> xid)
break;
}
if (!client ||
(packet -> interface -> hw_address.hlen - 1 !=
packet -> raw -> hlen) ||
(memcmp (&packet -> interface -> hw_address.hbuf [1],
packet -> raw -> chaddr, packet -> raw -> hlen))) {
#if defined (DEBUG)
log_debug ("DHCPACK in wrong transaction.");
#endif
return;
}
if (client -> state != S_REBOOTING &&
client -> state != S_REQUESTING &&
client -> state != S_RENEWING &&
client -> state != S_REBINDING) {
#if defined (DEBUG)
log_debug ("DHCPACK in wrong state.");
#endif
return;
}
log_info ("DHCPACK from %s", piaddr (packet -> client_addr));
lease = packet_to_lease (packet, client);
if (!lease) {
log_info ("packet_to_lease failed.");
return;
}
client -> new = lease;
/* Stop resending DHCPREQUEST. */
cancel_timeout (send_request, client);
/* Figure out the lease time. */
oc = lookup_option (&dhcp_universe, client -> new -> options,
DHO_DHCP_LEASE_TIME);
memset (&ds, 0, sizeof ds);
if (oc &&
evaluate_option_cache (&ds, packet, (struct lease *)0,
packet -> options, client -> new -> options,
&global_scope, oc, MDL)) {
if (ds.len > 3)
client -> new -> expiry = getULong (ds.data);
else
client -> new -> expiry = 0;
data_string_forget (&ds, MDL);
} else
client -> new -> expiry = 0;
if (!client -> new -> expiry) {
log_error ("no expiry time on offered lease.");
/* XXX this is going to be bad - if this _does_
XXX happen, we should probably dynamically
XXX disqualify the DHCP server that gave us the
XXX bad packet from future selections and
XXX then go back into the init state. */
state_init (client);
return;
}
/* A number that looks negative here is really just very large,
because the lease expiry offset is unsigned. */
if (client -> new -> expiry < 0)
client -> new -> expiry = TIME_MAX;
/* Take the server-provided renewal time if there is one. */
oc = lookup_option (&dhcp_universe, client -> new -> options,
DHO_DHCP_RENEWAL_TIME);
if (oc &&
evaluate_option_cache (&ds, packet, (struct lease *)0,
packet -> options, client -> new -> options,
&global_scope, oc, MDL)) {
if (ds.len > 3)
client -> new -> renewal = getULong (ds.data);
else
client -> new -> renewal = 0;
data_string_forget (&ds, MDL);
} else
client -> new -> renewal = 0;
/* If it wasn't specified by the server, calculate it. */
if (!client -> new -> renewal)
client -> new -> renewal =
client -> new -> expiry / 2;
/* Now introduce some randomness to the renewal time: */
client -> new -> renewal = (((client -> new -> renewal + 3) * 3 / 4) +
(random () % /* XXX NUMS */
((client -> new -> renewal + 3) / 4)));
/* Same deal with the rebind time. */
oc = lookup_option (&dhcp_universe, client -> new -> options,
DHO_DHCP_REBINDING_TIME);
if (oc &&
evaluate_option_cache (&ds, packet, (struct lease *)0,
packet -> options, client -> new -> options,
&global_scope, oc, MDL)) {
if (ds.len > 3)
client -> new -> rebind = getULong (ds.data);
else
client -> new -> rebind = 0;
data_string_forget (&ds, MDL);
} else
client -> new -> rebind = 0;
if (!client -> new -> rebind)
client -> new -> rebind =
(client -> new -> expiry * 7) / 8; /* XXX NUMS */
/* Make sure our randomness didn't run the renewal time past the
rebind time. */
if (client -> new -> renewal > client -> new -> rebind)
client -> new -> renewal = (client -> new -> rebind * 3) / 4;
client -> new -> expiry += cur_time;
/* Lease lengths can never be negative. */
if (client -> new -> expiry < cur_time)
client -> new -> expiry = TIME_MAX;
client -> new -> renewal += cur_time;
if (client -> new -> renewal < cur_time)
client -> new -> renewal = TIME_MAX;
client -> new -> rebind += cur_time;
if (client -> new -> rebind < cur_time)
client -> new -> rebind = TIME_MAX;
bind_lease (client);
}
void bind_lease (client)
struct client_state *client;
{
struct interface_info *ip = client -> interface;
/* Remember the medium. */
client -> new -> medium = client -> medium;
/* Run the client script with the new parameters. */
script_init (client, (client -> state == S_REQUESTING
? "BOUND"
: (client -> state == S_RENEWING
? "RENEW"
: (client -> state == S_REBOOTING
? "REBOOT" : "REBIND"))),
client -> new -> medium);
if (client -> active && client -> state != S_REBOOTING)
script_write_params (client, "old_", client -> active);
script_write_params (client, "new_", client -> new);
if (client -> alias)
script_write_params (client, "alias_", client -> alias);
/* If the BOUND/RENEW code detects another machine using the
offered address, it exits nonzero. We need to send a
DHCPDECLINE and toss the lease. */
if (script_go (client)) {
make_decline (client, client -> new);
send_decline (client);
destroy_client_lease (client -> new);
client -> new = (struct client_lease *)0;
state_init (client);
return;
}
/* Write out the new lease. */
write_client_lease (client, client -> new, 0, 0);
/* Replace the old active lease with the new one. */
if (client -> active)
destroy_client_lease (client -> active);
client -> active = client -> new;
client -> new = (struct client_lease *)0;
/* Set up a timeout to start the renewal process. */
add_timeout (client -> active -> renewal,
state_bound, client, 0, 0);
log_info ("bound to %s -- renewal in %ld seconds.",
piaddr (client -> active -> address),
(long)(client -> active -> renewal - cur_time));
client -> state = S_BOUND;
reinitialize_interfaces ();
go_daemon ();
}
/* state_bound is called when we've successfully bound to a particular
lease, but the renewal time on that lease has expired. We are
expected to unicast a DHCPREQUEST to the server that gave us our
original lease. */
void state_bound (cpp)
void *cpp;
{
struct client_state *client = cpp;
int i;
struct option_cache *oc;
struct data_string ds;
ASSERT_STATE(state, S_BOUND);
/* T1 has expired. */
make_request (client, client -> active);
client -> xid = client -> packet.xid;
memset (&ds, 0, sizeof ds);
oc = lookup_option (&dhcp_universe, client -> active -> options,
DHO_DHCP_SERVER_IDENTIFIER);
if (oc &&
evaluate_option_cache (&ds, (struct packet *)0, (struct lease *)0,
(struct option_state *)0,
client -> active -> options,
&global_scope, oc, MDL)) {
if (ds.len > 3) {
memcpy (client -> destination.iabuf, ds.data, 4);
client -> destination.len = 4;
} else
client -> destination = iaddr_broadcast;
} else
client -> destination = iaddr_broadcast;
client -> first_sending = cur_time;
client -> interval = client -> config -> initial_interval;
client -> state = S_RENEWING;
/* Send the first packet immediately. */
send_request (client);
}
int commit_leases ()
{
return 0;
}
int write_lease (lease)
struct lease *lease;
{
return 0;
}
int write_host (host)
struct host_decl *host;
{
return 0;
}
void db_startup (testp)
int testp;
{
}
void bootp (packet)
struct packet *packet;
{
struct iaddrlist *ap;
if (packet -> raw -> op != BOOTREPLY)
return;
/* If there's a reject list, make sure this packet's sender isn't
on it. */
for (ap = packet -> interface -> client -> config -> reject_list;
ap; ap = ap -> next) {
if (addr_eq (packet -> client_addr, ap -> addr)) {
log_info ("BOOTREPLY from %s rejected.",
piaddr (ap -> addr));
return;
}
}
dhcpoffer (packet);
}
void dhcp (packet)
struct packet *packet;
{
struct iaddrlist *ap;
void (*handler) PROTO ((struct packet *));
const char *type;
switch (packet -> packet_type) {
case DHCPOFFER:
handler = dhcpoffer;
type = "DHCPOFFER";
break;
case DHCPNAK:
handler = dhcpnak;
type = "DHCPNACK";
break;
case DHCPACK:
handler = dhcpack;
type = "DHCPACK";
break;
default:
return;
}
/* If there's a reject list, make sure this packet's sender isn't
on it. */
for (ap = packet -> interface -> client -> config -> reject_list;
ap; ap = ap -> next) {
if (addr_eq (packet -> client_addr, ap -> addr)) {
log_info ("%s from %s rejected.",
type, piaddr (ap -> addr));
return;
}
}
(*handler) (packet);
}
void dhcpoffer (packet)
struct packet *packet;
{
struct interface_info *ip = packet -> interface;
struct client_state *client;
struct client_lease *lease, *lp;
int i;
int stop_selecting;
const char *name = packet -> packet_type ? "DHCPOFFER" : "BOOTREPLY";
struct iaddrlist *ap;
struct option_cache *oc;
#ifdef DEBUG_PACKET
dump_packet (packet);
#endif
/* Find a client state that matches the xid... */
for (client = ip -> client; client; client = client -> next)
if (client -> xid == packet -> raw -> xid)
break;
/* If we're not receptive to an offer right now, or if the offer
has an unrecognizable transaction id, then just drop it. */
if (!client ||
client -> state != S_SELECTING ||
(packet -> interface -> hw_address.hlen - 1 !=
packet -> raw -> hlen) ||
(memcmp (&packet -> interface -> hw_address.hbuf [1],
packet -> raw -> chaddr, packet -> raw -> hlen))) {
#if defined (DEBUG)
log_debug ("%s in wrong transaction.", name);
#endif
return;
}
log_info ("%s from %s", name, piaddr (packet -> client_addr));
/* If this lease doesn't supply the minimum required parameters,
blow it off. */
if (client -> config -> required_options) {
for (i = 0; client -> config -> required_options [i]; i++) {
if (!lookup_option
(&dhcp_universe, packet -> options,
client -> config -> required_options [i])) {
log_info ("%s isn't satisfactory.", name);
return;
}
}
}
/* If we've already seen this lease, don't record it again. */
for (lease = client -> offered_leases; lease; lease = lease -> next) {
if (lease -> address.len == sizeof packet -> raw -> yiaddr &&
!memcmp (lease -> address.iabuf,
&packet -> raw -> yiaddr, lease -> address.len)) {
log_debug ("%s already seen.", name);
return;
}
}
lease = packet_to_lease (packet, client);
if (!lease) {
log_info ("packet_to_lease failed.");
return;
}
/* If this lease was acquired through a BOOTREPLY, record that
fact. */
if (!packet -> options_valid || !packet -> packet_type)
lease -> is_bootp = 1;
/* Record the medium under which this lease was offered. */
lease -> medium = client -> medium;
/* Figure out when we're supposed to stop selecting. */
stop_selecting = (client -> first_sending +
client -> config -> select_interval);
/* If this is the lease we asked for, put it at the head of the
list, and don't mess with the arp request timeout. */
if (lease -> address.len == client -> requested_address.len &&
!memcmp (lease -> address.iabuf,
client -> requested_address.iabuf,
client -> requested_address.len)) {
lease -> next = client -> offered_leases;
client -> offered_leases = lease;
} else {
/* Put the lease at the end of the list. */
lease -> next = (struct client_lease *)0;
if (!client -> offered_leases)
client -> offered_leases = lease;
else {
for (lp = client -> offered_leases; lp -> next;
lp = lp -> next)
;
lp -> next = lease;
}
}
/* If the selecting interval has expired, go immediately to
state_selecting(). Otherwise, time out into
state_selecting at the select interval. */
if (stop_selecting <= 0)
state_selecting (ip);
else {
add_timeout (stop_selecting, state_selecting, client, 0, 0);
cancel_timeout (send_discover, client);
}
}
/* Allocate a client_lease structure and initialize it from the parameters
in the specified packet. */
struct client_lease *packet_to_lease (packet, client)
struct packet *packet;
struct client_state *client;
{
struct client_lease *lease;
int i;
struct option_cache *oc;
struct data_string data;
lease = (struct client_lease *)new_client_lease (MDL);
if (!lease) {
log_error ("dhcpoffer: no memory to record lease.\n");
return (struct client_lease *)0;
}
memset (lease, 0, sizeof *lease);
/* Copy the lease options. */
option_state_reference (&lease -> options, packet -> options, MDL);
lease -> address.len = sizeof (packet -> raw -> yiaddr);
memcpy (lease -> address.iabuf, &packet -> raw -> yiaddr,
lease -> address.len);
/* Figure out the overload flag. */
oc = lookup_option (&dhcp_universe, lease -> options,
DHO_DHCP_OPTION_OVERLOAD);
memset (&data, 0, sizeof data);
if (oc &&
evaluate_option_cache (&data, packet, (struct lease *)0,
packet -> options, lease -> options,
&global_scope, oc, MDL)) {
if (data.len > 0)
i = data.data [0];
else
i = 0;
data_string_forget (&data, MDL);
} else
i = 0;
/* If the server name was filled out, copy it. */
if (!(i & 2) && packet -> raw -> sname [0]) {
unsigned len;
/* Don't count on the NUL terminator. */
for (len = 0; len < 64; len++)
if (!packet -> raw -> sname [len])
break;
lease -> server_name = dmalloc (len + 1, MDL);
if (!lease -> server_name) {
log_error ("dhcpoffer: no memory for filename.\n");
destroy_client_lease (lease);
return (struct client_lease *)0;
} else {
memcpy (lease -> server_name,
packet -> raw -> sname, len);
lease -> server_name [len] = 0;
}
}
/* Ditto for the filename. */
if (!(i & 1) && packet -> raw -> file [0]) {
unsigned len;
/* Don't count on the NUL terminator. */
for (len = 0; len < 64; len++)
if (!packet -> raw -> file [len])
break;
lease -> filename = dmalloc (len + 1, MDL);
if (!lease -> filename) {
log_error ("dhcpoffer: no memory for filename.\n");
destroy_client_lease (lease);
return (struct client_lease *)0;
} else {
memcpy (lease -> filename,
packet -> raw -> file, len);
lease -> filename [len] = 0;
}
}
return lease;
}
void dhcpnak (packet)
struct packet *packet;
{
struct interface_info *ip = packet -> interface;
struct client_state *client;
/* Find a client state that matches the xid... */
for (client = ip -> client; client; client = client -> next)
if (client -> xid == packet -> raw -> xid)
break;
/* If we're not receptive to an offer right now, or if the offer
has an unrecognizable transaction id, then just drop it. */
if (!client ||
(packet -> interface -> hw_address.hlen - 1 !=
packet -> raw -> hlen) ||
(memcmp (&packet -> interface -> hw_address.hbuf [1],
packet -> raw -> chaddr, packet -> raw -> hlen))) {
#if defined (DEBUG)
log_debug ("DHCPNAK in wrong transaction.");
#endif
return;
}
if (client -> state != S_REBOOTING &&
client -> state != S_REQUESTING &&
client -> state != S_RENEWING &&
client -> state != S_REBINDING) {
#if defined (DEBUG)
log_debug ("DHCPNAK in wrong state.");
#endif
return;
}
log_info ("DHCPNAK from %s", piaddr (packet -> client_addr));
if (!client -> active) {
#if defined (DEBUG)
log_info ("DHCPNAK with no active lease.\n");
#endif
return;
}
destroy_client_lease (client -> active);
client -> active = (struct client_lease *)0;
/* Stop sending DHCPREQUEST packets... */
cancel_timeout (send_request, client);
client -> state = S_INIT;
state_init (client);
}
/* Send out a DHCPDISCOVER packet, and set a timeout to send out another
one after the right interval has expired. If we don't get an offer by
the time we reach the panic interval, call the panic function. */
void send_discover (cpp)
void *cpp;
{
struct client_state *client = cpp;
int result;
int interval;
int increase = 1;
/* Figure out how long it's been since we started transmitting. */
interval = cur_time - client -> first_sending;
/* If we're past the panic timeout, call the script and tell it
we haven't found anything for this interface yet. */
if (interval > client -> config -> timeout) {
state_panic (client);
return;
}
/* If we're selecting media, try the whole list before doing
the exponential backoff, but if we've already received an
offer, stop looping, because we obviously have it right. */
if (!client -> offered_leases &&
client -> config -> media) {
int fail = 0;
again:
if (client -> medium) {
client -> medium = client -> medium -> next;
increase = 0;
}
if (!client -> medium) {
if (fail)
log_fatal ("No valid media types for %s!",
client -> interface -> name);
client -> medium =
client -> config -> media;
increase = 1;
}
log_info ("Trying medium \"%s\" %d",
client -> medium -> string, increase);
script_init (client, "MEDIUM", client -> medium);
if (script_go (client)) {
goto again;
}
}
/* If we're supposed to increase the interval, do so. If it's
currently zero (i.e., we haven't sent any packets yet), set
it to one; otherwise, add to it a random number between
zero and two times itself. On average, this means that it
will double with every transmission. */
if (increase) {
if (!client -> interval)
client -> interval =
client -> config -> initial_interval;
else {
client -> interval +=
((random () >> 2) %
(2 * client -> interval));
}
/* Don't backoff past cutoff. */
if (client -> interval >
client -> config -> backoff_cutoff)
client -> interval =
((client -> config -> backoff_cutoff / 2)
+ ((random () >> 2) %
client -> config -> backoff_cutoff));
} else if (!client -> interval)
client -> interval = client -> config -> initial_interval;
/* If the backoff would take us to the panic timeout, just use that
as the interval. */
if (cur_time + client -> interval >
client -> first_sending + client -> config -> timeout)
client -> interval =
(client -> first_sending +
client -> config -> timeout) - cur_time + 1;
/* Record the number of seconds since we started sending. */
if (interval < 65536)
client -> packet.secs = htons (interval);
else
client -> packet.secs = htons (65535);
client -> secs = client -> packet.secs;
log_info ("DHCPDISCOVER on %s to %s port %d interval %ld",
client -> name ? client -> name : client -> interface -> name,
inet_ntoa (sockaddr_broadcast.sin_addr),
ntohs (sockaddr_broadcast.sin_port), client -> interval);
/* Send out a packet. */
result = send_packet (client -> interface, (struct packet *)0,
&client -> packet,
client -> packet_length,
inaddr_any, &sockaddr_broadcast,
(struct hardware *)0);
add_timeout (cur_time + client -> interval,
send_discover, client, 0, 0);
}
/* state_panic gets called if we haven't received any offers in a preset
amount of time. When this happens, we try to use existing leases that
haven't yet expired, and failing that, we call the client script and
hope it can do something. */
void state_panic (cpp)
void *cpp;
{
struct client_state *client = cpp;
struct client_lease *loop;
struct client_lease *lp;
loop = lp = client -> active;
log_info ("No DHCPOFFERS received.");
/* We may not have an active lease, but we may have some
predefined leases that we can try. */
if (!client -> active && client -> leases)
goto activate_next;
/* Run through the list of leases and see if one can be used. */
while (client -> active) {
if (client -> active -> expiry > cur_time) {
log_info ("Trying recorded lease %s",
piaddr (client -> active -> address));
/* Run the client script with the existing
parameters. */
script_init (client, "TIMEOUT",
client -> active -> medium);
script_write_params (client, "new_", client -> active);
if (client -> alias)
script_write_params (client, "alias_",
client -> alias);
/* If the old lease is still good and doesn't
yet need renewal, go into BOUND state and
timeout at the renewal time. */
if (!script_go (client)) {
if (cur_time < client -> active -> renewal) {
client -> state = S_BOUND;
log_info ("bound: renewal in %ld %s.",
(long)(client -> active -> renewal -
cur_time), "seconds");
add_timeout (client -> active -> renewal,
state_bound, client, 0, 0);
} else {
client -> state = S_BOUND;
log_info ("bound: immediate renewal.");
state_bound (client);
}
reinitialize_interfaces ();
go_daemon ();
return;
}
}
/* If there are no other leases, give up. */
if (!client -> leases) {
client -> leases = client -> active;
client -> active = (struct client_lease *)0;
break;
}
activate_next:
/* Otherwise, put the active lease at the end of the
lease list, and try another lease.. */
for (lp = client -> leases; lp -> next; lp = lp -> next)
;
lp -> next = client -> active;
if (lp -> next) {
lp -> next -> next = (struct client_lease *)0;
}
client -> active = client -> leases;
client -> leases = client -> leases -> next;
/* If we already tried this lease, we've exhausted the
set of leases, so we might as well give up for
now. */
if (client -> active == loop)
break;
else if (!loop)
loop = client -> active;
}
/* No leases were available, or what was available didn't work, so
tell the shell script that we failed to allocate an address,
and try again later. */
log_info ("No working leases in persistent database - sleeping.");
script_init (client, "FAIL", (struct string_list *)0);
if (client -> alias)
script_write_params (client, "alias_", client -> alias);
script_go (client);
client -> state = S_INIT;
add_timeout (cur_time +
((client -> config -> retry_interval + 1) / 2 +
(random () % client -> config -> retry_interval)),
state_init, client, 0, 0);
go_daemon ();
}
void send_request (cpp)
void *cpp;
{
struct client_state *client = cpp;
int result;
int interval;
struct sockaddr_in destination;
struct in_addr from;
/* Figure out how long it's been since we started transmitting. */
interval = cur_time - client -> first_sending;
/* If we're in the INIT-REBOOT or REQUESTING state and we're
past the reboot timeout, go to INIT and see if we can
DISCOVER an address... */
/* XXX In the INIT-REBOOT state, if we don't get an ACK, it
means either that we're on a network with no DHCP server,
or that our server is down. In the latter case, assuming
that there is a backup DHCP server, DHCPDISCOVER will get
us a new address, but we could also have successfully
reused our old address. In the former case, we're hosed
anyway. This is not a win-prone situation. */
if ((client -> state == S_REBOOTING ||
client -> state == S_REQUESTING) &&
interval > client -> config -> reboot_timeout) {
cancel:
client -> state = S_INIT;
cancel_timeout (send_request, client);
state_init (client);
return;
}
/* If we're in the reboot state, make sure the media is set up
correctly. */
if (client -> state == S_REBOOTING &&
!client -> medium &&
client -> active -> medium ) {
script_init (client, "MEDIUM", client -> active -> medium);
/* If the medium we chose won't fly, go to INIT state. */
if (script_go (client))
goto cancel;
/* Record the medium. */
client -> medium = client -> active -> medium;
}
/* If the lease has expired, relinquish the address and go back
to the INIT state. */
if (client -> state != S_REQUESTING &&
cur_time > client -> active -> expiry) {
/* Run the client script with the new parameters. */
script_init (client, "EXPIRE", (struct string_list *)0);
script_write_params (client, "old_", client -> active);
if (client -> alias)
script_write_params (client, "alias_",
client -> alias);
script_go (client);
/* Now do a preinit on the interface so that we can
discover a new address. */
script_init (client, "PREINIT", (struct string_list *)0);
if (client -> alias)
script_write_params (client, "alias_",
client -> alias);
script_go (client);
client -> state = S_INIT;
state_init (client);
return;
}
/* Do the exponential backoff... */
if (!client -> interval)
client -> interval = client -> config -> initial_interval;
else {
client -> interval += ((random () >> 2) %
(2 * client -> interval));
}
/* Don't backoff past cutoff. */
if (client -> interval >
client -> config -> backoff_cutoff)
client -> interval =
((client -> config -> backoff_cutoff / 2)
+ ((random () >> 2) % client -> interval));
/* If the backoff would take us to the expiry time, just set the
timeout to the expiry time. */
if (client -> state != S_REQUESTING &&
cur_time + client -> interval > client -> active -> expiry)
client -> interval =
client -> active -> expiry - cur_time + 1;
/* If the lease T2 time has elapsed, or if we're not yet bound,
broadcast the DHCPREQUEST rather than unicasting. */
if (client -> state == S_REQUESTING ||
client -> state == S_REBOOTING ||
cur_time > client -> active -> rebind)
destination.sin_addr = sockaddr_broadcast.sin_addr;
else
memcpy (&destination.sin_addr.s_addr,
client -> destination.iabuf,
sizeof destination.sin_addr.s_addr);
destination.sin_port = remote_port;
destination.sin_family = AF_INET;
#ifdef HAVE_SA_LEN
destination.sin_len = sizeof destination;
#endif
if (client -> state == S_RENEWING ||
client -> state == S_REBINDING)
memcpy (&from, client -> active -> address.iabuf,
sizeof from);
else
from.s_addr = INADDR_ANY;
/* Record the number of seconds since we started sending. */
if (client -> state == S_REQUESTING)
client -> packet.secs = client -> secs;
else {
if (interval < 65536)
client -> packet.secs = htons (interval);
else
client -> packet.secs = htons (65535);
}
log_info ("DHCPREQUEST on %s to %s port %d",
client -> name ? client -> name : client -> interface -> name,
inet_ntoa (destination.sin_addr),
ntohs (destination.sin_port));
if (destination.sin_addr.s_addr != INADDR_BROADCAST &&
fallback_interface)
result = send_packet (fallback_interface,
(struct packet *)0,
&client -> packet,
client -> packet_length,
from, &destination,
(struct hardware *)0);
else
/* Send out a packet. */
result = send_packet (client -> interface, (struct packet *)0,
&client -> packet,
client -> packet_length,
from, &destination,
(struct hardware *)0);
add_timeout (cur_time + client -> interval,
send_request, client, 0, 0);
}
void send_decline (cpp)
void *cpp;
{
struct client_state *client = cpp;
int result;
log_info ("DHCPDECLINE on %s to %s port %d",
client -> name ? client -> name : client -> interface -> name,
inet_ntoa (sockaddr_broadcast.sin_addr),
ntohs (sockaddr_broadcast.sin_port));
/* Send out a packet. */
result = send_packet (client -> interface, (struct packet *)0,
&client -> packet,
client -> packet_length,
inaddr_any, &sockaddr_broadcast,
(struct hardware *)0);
}
void send_release (cpp)
void *cpp;
{
struct client_state *client = cpp;
int result;
struct sockaddr_in destination;
struct in_addr from;
memcpy (&from, client -> active -> address.iabuf,
sizeof from);
memcpy (&destination.sin_addr.s_addr,
client -> destination.iabuf,
sizeof destination.sin_addr.s_addr);
destination.sin_port = remote_port;
destination.sin_family = AF_INET;
#ifdef HAVE_SA_LEN
destination.sin_len = sizeof destination;
#endif
/* Set the lease to end now, so that we don't accidentally
reuse it if we restart before the old expiry time. */
client -> active -> expiry =
client -> active -> renewal =
client -> active -> rebind = cur_time;
if (!write_client_lease (client, client -> active, 1, 1)) {
log_error ("Can't release lease: lease write failed.");
return;
}
log_info ("DHCPRELEASE on %s to %s port %d",
client -> name ? client -> name : client -> interface -> name,
inet_ntoa (destination.sin_addr),
ntohs (destination.sin_port));
if (fallback_interface)
result = send_packet (fallback_interface,
(struct packet *)0,
&client -> packet,
client -> packet_length,
from, &destination,
(struct hardware *)0);
else
/* Send out a packet. */
result = send_packet (client -> interface, (struct packet *)0,
&client -> packet,
client -> packet_length,
from, &destination,
(struct hardware *)0);
}
void make_client_options (client, lease, type, sid, rip, prl, op)
struct client_state *client;
struct client_lease *lease;
u_int8_t *type;
struct option_cache *sid;
struct iaddr *rip;
u_int32_t *prl;
struct option_state **op;
{
unsigned i;
struct option_cache *oc;
struct buffer *bp = (struct buffer *)0;
/* Allocate space for options. */
option_state_allocate (op, MDL);
/* Send the server identifier if provided. */
if (sid)
save_option (&dhcp_universe, *op, sid);
oc = (struct option_cache *)0;
/* Send the requested address if provided. */
if (rip) {
client -> requested_address = *rip;
if (!(make_const_option_cache
(&oc, (struct buffer **)0, rip -> iabuf, rip -> len,
&dhcp_options [DHO_DHCP_REQUESTED_ADDRESS], MDL)))
log_error ("can't make requested address cache.");
else {
save_option (&dhcp_universe, *op, oc);
option_cache_dereference (&oc, MDL);
}
} else {
client -> requested_address.len = 0;
}
if (!(make_const_option_cache
(&oc, (struct buffer **)0,
type, 1, &dhcp_options [DHO_DHCP_MESSAGE_TYPE], MDL)))
log_error ("can't make message type.");
else {
save_option (&dhcp_universe, *op, oc);
option_cache_dereference (&oc, MDL);
}
if (prl) {
/* Figure out how many parameters were requested. */
for (i = 0; prl [i]; i++)
;
if (!buffer_allocate (&bp, i, MDL))
log_error ("can't make parameter list buffer.");
else {
for (i = 0; prl [i]; i++)
bp -> data [i] = prl [i];
if (!(make_const_option_cache
(&oc, &bp, (u_int8_t *)0, i,
&dhcp_options [DHO_DHCP_PARAMETER_REQUEST_LIST],
MDL)))
log_error ("can't make option cache");
else {
save_option (&dhcp_universe, *op, oc);
option_cache_dereference (&oc, MDL);
}
}
}
/* Run statements that need to be run on transmission. */
if (client -> config -> on_transmission)
execute_statements_in_scope
((struct binding_value **)0,
(struct packet *)0, (struct lease *)0,
(lease ? lease -> options : (struct option_state *)0),
*op, &global_scope,
client -> config -> on_transmission,
(struct group *)0);
}
void make_discover (client, lease)
struct client_state *client;
struct client_lease *lease;
{
struct dhcp_packet *raw;
unsigned char discover = DHCPDISCOVER;
int i;
struct option_state *options = (struct option_state *)0;
memset (&client -> packet, 0, sizeof (client -> packet));
make_client_options (client,
lease, &discover, (struct option_cache *)0,
lease ? &lease -> address : (struct iaddr *)0,
client -> config -> requested_options,
&options);
/* Set up the option buffer... */
client -> packet_length =
cons_options ((struct packet *)0, &client -> packet,
(struct lease *)0, 0,
(struct option_state *)0, options,
&global_scope, 0, 0, 0, (struct data_string *)0);
if (client -> packet_length < BOOTP_MIN_LEN)
client -> packet_length = BOOTP_MIN_LEN;
client -> packet.op = BOOTREQUEST;
client -> packet.htype = client -> interface -> hw_address.hbuf [0];
client -> packet.hlen = client -> interface -> hw_address.hlen - 1;
client -> packet.hops = 0;
client -> packet.xid = random ();
client -> packet.secs = 0; /* filled in by send_discover. */
if (can_receive_unicast_unconfigured (client -> interface))
client -> packet.flags = 0;
else
client -> packet.flags = htons (BOOTP_BROADCAST);
memset (&(client -> packet.ciaddr),
0, sizeof client -> packet.ciaddr);
memset (&(client -> packet.yiaddr),
0, sizeof client -> packet.yiaddr);
memset (&(client -> packet.siaddr),
0, sizeof client -> packet.siaddr);
client -> packet.giaddr = giaddr;
if (client -> interface -> hw_address.hlen > 0)
memcpy (client -> packet.chaddr,
&client -> interface -> hw_address.hbuf [1],
(unsigned)(client -> interface -> hw_address.hlen - 1));
#ifdef DEBUG_PACKET
dump_packet (sendpkt);
dump_raw ((unsigned char *)client -> packet,
sendpkt->packet_length);
#endif
}
void make_request (client, lease)
struct client_state *client;
struct client_lease *lease;
{
unsigned char request = DHCPREQUEST;
int i, j;
unsigned char *tmp, *digest;
unsigned char *old_digest_loc;
struct option_state *options = (struct option_state *)0;
struct option_cache *oc;
memset (&client -> packet, 0, sizeof (client -> packet));
if (client -> state == S_REQUESTING)
oc = lookup_option (&dhcp_universe, lease -> options,
DHO_DHCP_SERVER_IDENTIFIER);
else
oc = (struct option_cache *)0;
make_client_options (client, lease, &request, oc,
((client -> state == S_REQUESTING ||
client -> state == S_REBOOTING)
? &lease -> address
: (struct iaddr *)0),
client -> config -> requested_options,
&options);
/* Set up the option buffer... */
client -> packet_length =
cons_options ((struct packet *)0, &client -> packet,
(struct lease *)0, 0,
(struct option_state *)0, options,
&global_scope, 0, 0, 0, (struct data_string *)0);
if (client -> packet_length < BOOTP_MIN_LEN)
client -> packet_length = BOOTP_MIN_LEN;
client -> packet.op = BOOTREQUEST;
client -> packet.htype = client -> interface -> hw_address.hbuf [0];
client -> packet.hlen = client -> interface -> hw_address.hlen - 1;
client -> packet.hops = 0;
client -> packet.xid = client -> xid;
client -> packet.secs = 0; /* Filled in by send_request. */
/* If we own the address we're requesting, put it in ciaddr;
otherwise set ciaddr to zero. */
if (client -> state == S_BOUND ||
client -> state == S_RENEWING ||
client -> state == S_REBINDING) {
memcpy (&client -> packet.ciaddr,
lease -> address.iabuf, lease -> address.len);
client -> packet.flags = 0;
} else {
memset (&client -> packet.ciaddr, 0,
sizeof client -> packet.ciaddr);
if (can_receive_unicast_unconfigured (client -> interface))
client -> packet.flags = 0;
else
client -> packet.flags = htons (BOOTP_BROADCAST);
}
memset (&client -> packet.yiaddr, 0,
sizeof client -> packet.yiaddr);
memset (&client -> packet.siaddr, 0,
sizeof client -> packet.siaddr);
client -> packet.giaddr = giaddr;
if (client -> interface -> hw_address.hlen > 0)
memcpy (client -> packet.chaddr,
&client -> interface -> hw_address.hbuf [1],
(unsigned)(client -> interface -> hw_address.hlen - 1));
#ifdef DEBUG_PACKET
dump_packet (sendpkt);
dump_raw ((unsigned char *)client -> packet, sendpkt->packet_length);
#endif
}
void make_decline (client, lease)
struct client_state *client;
struct client_lease *lease;
{
unsigned char decline = DHCPDECLINE;
int i;
struct option_cache *oc;
struct option_state *options = (struct option_state *)0;
oc = lookup_option (&dhcp_universe, lease -> options,
DHO_DHCP_SERVER_IDENTIFIER);
make_client_options (client, lease, &decline, oc,
&lease -> address, (u_int32_t *)0, &options);
/* Set up the option buffer... */
memset (&client -> packet, 0, sizeof (client -> packet));
client -> packet_length =
cons_options ((struct packet *)0, &client -> packet,
(struct lease *)0, 0,
(struct option_state *)0, options,
&global_scope, 0, 0, 0, (struct data_string *)0);
if (client -> packet_length < BOOTP_MIN_LEN)
client -> packet_length = BOOTP_MIN_LEN;
option_state_dereference (&options, MDL);
client -> packet.op = BOOTREQUEST;
client -> packet.htype = client -> interface -> hw_address.hbuf [0];
client -> packet.hlen = client -> interface -> hw_address.hlen - 1;
client -> packet.hops = 0;
client -> packet.xid = client -> xid;
client -> packet.secs = 0; /* Filled in by send_request. */
if (can_receive_unicast_unconfigured (client -> interface))
client -> packet.flags = 0;
else
client -> packet.flags = htons (BOOTP_BROADCAST);
/* ciaddr must always be zero. */
memset (&client -> packet.ciaddr, 0,
sizeof client -> packet.ciaddr);
memset (&client -> packet.yiaddr, 0,
sizeof client -> packet.yiaddr);
memset (&client -> packet.siaddr, 0,
sizeof client -> packet.siaddr);
client -> packet.giaddr = giaddr;
memcpy (client -> packet.chaddr,
&client -> interface -> hw_address.hbuf [1],
client -> interface -> hw_address.hlen);
#ifdef DEBUG_PACKET
dump_packet (sendpkt);
dump_raw ((unsigned char *)client -> packet, sendpkt->packet_length);
#endif
}
void make_release (client, lease)
struct client_state *client;
struct client_lease *lease;
{
unsigned char request = DHCPRELEASE;
int i;
struct option_cache *oc;
struct option_state *options = (struct option_state *)0;
memset (&client -> packet, 0, sizeof (client -> packet));
oc = lookup_option (&dhcp_universe, lease -> options,
DHO_DHCP_SERVER_IDENTIFIER);
make_client_options (client, lease, &request, oc,
(struct iaddr *)0, (u_int32_t *)0,
&options);
/* Set up the option buffer... */
client -> packet_length =
cons_options ((struct packet *)0, &client -> packet,
(struct lease *)0, 0,
(struct option_state *)0, options,
&global_scope, 0, 0, 0, (struct data_string *)0);
if (client -> packet_length < BOOTP_MIN_LEN)
client -> packet_length = BOOTP_MIN_LEN;
option_state_dereference (&options, MDL);
client -> packet.op = BOOTREQUEST;
client -> packet.htype = client -> interface -> hw_address.hbuf [0];
client -> packet.hlen = client -> interface -> hw_address.hlen - 1;
client -> packet.hops = 0;
client -> packet.xid = random ();
client -> packet.secs = 0;
client -> packet.flags = 0;
memcpy (&client -> packet.ciaddr,
lease -> address.iabuf, lease -> address.len);
memset (&client -> packet.yiaddr, 0,
sizeof client -> packet.yiaddr);
memset (&client -> packet.siaddr, 0,
sizeof client -> packet.siaddr);
client -> packet.giaddr = giaddr;
memcpy (client -> packet.chaddr,
&client -> interface -> hw_address.hbuf [1],
client -> interface -> hw_address.hlen);
#ifdef DEBUG_PACKET
dump_packet (sendpkt);
dump_raw ((unsigned char *)client -> packet,
client -> packet_length);
#endif
}
void destroy_client_lease (lease)
struct client_lease *lease;
{
int i;
if (lease -> server_name)
dfree (lease -> server_name, MDL);
if (lease -> filename)
dfree (lease -> filename, MDL);
option_state_dereference (&lease -> options, MDL);
free_client_lease (lease, MDL);
}
FILE *leaseFile;
void rewrite_client_leases ()
{
struct interface_info *ip;
struct client_state *client;
struct client_lease *lp;
if (leaseFile)
fclose (leaseFile);
leaseFile = fopen (path_dhclient_db, "w");
if (!leaseFile)
log_fatal ("can't create %s: %m", path_dhclient_db);
/* Write out all the leases attached to configured interfaces that
we know about. */
for (ip = interfaces; ip; ip = ip -> next) {
for (client = ip -> client; client; client = client -> next) {
for (lp = client -> leases; lp; lp = lp -> next) {
write_client_lease (client, lp, 1, 0);
}
if (client -> active)
write_client_lease (client,
client -> active, 1, 0);
}
}
/* Write out any leases that are attached to interfaces that aren't
currently configured. */
for (ip = dummy_interfaces; ip; ip = ip -> next) {
for (client = ip -> client; client; client = client -> next) {
for (lp = client -> leases; lp; lp = lp -> next) {
write_client_lease (client, lp, 1, 0);
}
if (client -> active)
write_client_lease (client,
client -> active, 1, 0);
}
}
fflush (leaseFile);
}
int write_client_lease (client, lease, rewrite, makesure)
struct client_state *client;
struct client_lease *lease;
int rewrite;
int makesure;
{
int i;
struct tm *t;
static int leases_written;
struct option_cache *oc;
struct data_string ds;
pair *hash;
int errors = 0;
if (!rewrite) {
if (leases_written++ > 20) {
rewrite_client_leases ();
leases_written = 0;
}
}
/* If the lease came from the config file, we don't need to stash
a copy in the lease database. */
if (lease -> is_static)
return 1;
if (!leaseFile) { /* XXX */
leaseFile = fopen (path_dhclient_db, "w");
if (!leaseFile)
log_fatal ("can't create %s: %m", path_dhclient_db);
}
errno = 0;
fprintf (leaseFile, "lease {\n");
if (lease -> is_bootp)
fprintf (leaseFile, " bootp;\n");
fprintf (leaseFile, " interface \"%s\";\n",
client -> interface -> name);
if (client -> name)
fprintf (leaseFile, " name \"%s\";\n", client -> name);
fprintf (leaseFile, " fixed-address %s;\n",
piaddr (lease -> address));
if (lease -> filename)
fprintf (leaseFile, " filename \"%s\";\n",
lease -> filename);
if (lease -> server_name)
fprintf (leaseFile, " server-name \"%s\";\n",
lease -> server_name);
if (lease -> medium)
fprintf (leaseFile, " medium \"%s\";\n",
lease -> medium -> string);
if (errno != 0) {
errors++;
errno = 0;
}
memset (&ds, 0, sizeof ds);
hash = lease -> options -> universes [dhcp_universe.index];
for (i = 0; i < OPTION_HASH_SIZE; i++) {
pair p;
/* XXX save _all_ options! XXX */
for (p = hash [i]; p; p = p -> cdr) {
oc = (struct option_cache *)p -> car;
if (evaluate_option_cache (&ds, (struct packet *)0,
(struct lease *)0,
(struct option_state *)0,
lease -> options,
&global_scope, oc, MDL)) {
fprintf (leaseFile,
" option %s %s;\n",
oc -> option -> name,
pretty_print_option
(oc -> option -> code,
ds.data, ds.len, 1, 1));
data_string_forget (&ds, MDL);
if (errno != 0) {
errors++;
errno = 0;
}
}
}
}
/* Note: the following is not a Y2K bug - it's a Y1.9K bug. Until
somebody invents a time machine, I think we can safely disregard
it. */
t = gmtime (&lease -> renewal);
fprintf (leaseFile,
" renew %d %d/%d/%d %02d:%02d:%02d;\n",
t -> tm_wday, t -> tm_year + 1900,
t -> tm_mon + 1, t -> tm_mday,
t -> tm_hour, t -> tm_min, t -> tm_sec);
t = gmtime (&lease -> rebind);
fprintf (leaseFile,
" rebind %d %d/%d/%d %02d:%02d:%02d;\n",
t -> tm_wday, t -> tm_year + 1900,
t -> tm_mon + 1, t -> tm_mday,
t -> tm_hour, t -> tm_min, t -> tm_sec);
t = gmtime (&lease -> expiry);
fprintf (leaseFile,
" expire %d %d/%d/%d %02d:%02d:%02d;\n",
t -> tm_wday, t -> tm_year + 1900,
t -> tm_mon + 1, t -> tm_mday,
t -> tm_hour, t -> tm_min, t -> tm_sec);
fprintf (leaseFile, "}\n");
fflush (leaseFile);
if (errno != 0) {
errors++;
errno = 0;
}
if (!errors && makesure) {
if (fsync (fileno (leaseFile)) < 0) {
log_info ("write_client_lease: %m");
return 0;
}
}
return errors ? 0 : 1;
}
/* Variables holding name of script and file pointer for writing to
script. Needless to say, this is not reentrant - only one script
can be invoked at a time. */
char scriptName [256];
FILE *scriptFile;
void script_init (client, reason, medium)
struct client_state *client;
const char *reason;
struct string_list *medium;
{
struct string_list *sl, *next;
if (client) {
for (sl = client -> env; sl; sl = next) {
next = sl -> next;
dfree (sl, MDL);
}
client -> env = (struct string_list *)0;
client -> envc = 0;
if (client -> interface) {
client_envadd (client, "", "interface", "%s",
client -> interface -> name);
}
if (client -> name)
client_envadd (client,
"", "client", "%s", client -> name);
if (medium)
client_envadd (client,
"", "medium", "%s", medium -> string);
client_envadd (client, "", "reason", "%s", reason);
}
}
void script_write_params (client, prefix, lease)
struct client_state *client;
const char *prefix;
struct client_lease *lease;
{
int i;
struct data_string data;
struct option_cache *oc;
pair *hash;
char *s, *t;
client_envadd (client,
prefix, "ip_address", "%s", piaddr (lease -> address));
/* For the benefit of Linux (and operating systems which may
have similar needs), compute the network address based on
the supplied ip address and netmask, if provided. Also
compute the broadcast address (the host address all ones
broadcast address, not the host address all zeroes
broadcast address). */
memset (&data, 0, sizeof data);
oc = lookup_option (&dhcp_universe, lease -> options, DHO_SUBNET_MASK);
if (oc && evaluate_option_cache (&data,
(struct packet *)0,
(struct lease *)0,
(struct option_state *)0,
lease -> options,
&global_scope, oc, MDL)) {
if (data.len > 3) {
struct iaddr netmask, subnet, broadcast;
memcpy (netmask.iabuf, data.data, data.len);
netmask.len = data.len;
data_string_forget (&data, MDL);
subnet = subnet_number (lease -> address, netmask);
if (subnet.len) {
client_envadd (client, prefix, "network_number",
"%s", piaddr (subnet));
oc = lookup_option (&dhcp_universe,
lease -> options,
DHO_BROADCAST_ADDRESS);
if (!oc ||
!(evaluate_option_cache
(&data, (struct packet *)0,
(struct lease *)0,
(struct option_state *)0,
lease -> options,
&global_scope, oc, MDL))) {
broadcast = broadcast_addr (subnet, netmask);
if (broadcast.len) {
client_envadd (client,
prefix, "broadcast_address",
"%s", piaddr (broadcast));
}
}
}
}
data_string_forget (&data, MDL);
}
if (lease -> filename)
client_envadd (client,
prefix, "filename", "%s", lease -> filename);
if (lease -> server_name)
client_envadd (client, prefix, "server_name",
"%s", lease -> server_name);
execute_statements_in_scope ((struct binding_value **)0,
(struct packet *)0,
(struct lease *)0, lease -> options,
lease -> options, &global_scope,
client -> config -> on_receipt,
(struct group *)0);
hash = lease -> options -> universes [dhcp_universe.index];
for (i = 0; i < OPTION_HASH_SIZE; i++) {
pair hp;
for (hp = hash [i]; hp; hp = hp -> cdr) {
oc = (struct option_cache *)hp -> car;
if (evaluate_option_cache (&data,
(struct packet *)0,
(struct lease *)0,
(struct option_state *)0,
lease -> options,
&global_scope, oc, MDL)) {
if (data.len) {
char name [256];
if (dhcp_option_ev_name (name, sizeof name,
oc -> option)) {
client_envadd (client, prefix, name, "%s",
(pretty_print_option
(oc -> option -> code,
data.data, data.len,
0, 0)));
data_string_forget (&data, MDL);
}
}
}
}
}
client_envadd (client, prefix, "expiry", "%d", (int)(lease -> expiry));
}
int script_go (client)
struct client_state *client;
{
int rval;
char *scriptName;
char *argv [2];
char **envp;
char *epp [3];
char reason [] = "REASON=NBI";
static char client_path [] = CLIENT_PATH;
int i;
struct string_list *sp, *next;
int pid, wpid, wstatus;
if (client) {
scriptName = client -> config -> script_name;
envp = dmalloc ((client -> envc + 2) * sizeof (char *),
MDL);
if (!envp) {
log_error ("No memory for client script environment.");
return 0;
}
i = 0;
for (sp = client -> env; sp; sp = sp -> next) {
envp [i++] = sp -> string;
}
envp [i++] = client_path;
envp [i] = (char *)0;
} else {
scriptName = top_level_config.script_name;
epp [0] = reason;
epp [1] = client_path;
epp [2] = (char *)0;
envp = epp;
}
argv [0] = scriptName;
argv [1] = (char *)0;
pid = fork ();
if (pid < 0) {
log_error ("fork: %m");
wstatus = 0;
} else if (pid) {
do {
wpid = wait (&wstatus);
} while (wpid != pid && wpid > 0);
if (wpid < 0) {
log_error ("wait: %m");
wstatus = 0;
}
} else {
execve (scriptName, argv, envp);
log_error ("execve (%s, ...): %m", scriptName);
exit (0);
}
if (client) {
for (sp = client -> env; sp; sp = next) {
next = sp -> next;
dfree (sp, MDL);
}
client -> env = (struct string_list *)0;
client -> envc = 0;
dfree (envp, MDL);
}
return wstatus & 0xff;
}
void client_envadd (struct client_state *client,
const char *prefix, const char *name, const char *fmt, ...)
{
char spbuf [1024];
char *s;
unsigned len, i;
struct string_list *val;
va_list list;
va_start (list, fmt);
len = vsnprintf (spbuf, sizeof spbuf, fmt, list);
va_end (list);
val = dmalloc (strlen (prefix) + strlen (name) + 1 /* = */ +
len + sizeof *val, MDL);
if (!val)
return;
s = val -> string;
strcpy (s, prefix);
strcat (s, name);
s += strlen (s);
*s++ = '=';
if (len >= sizeof spbuf) {
va_start (list, fmt);
vsnprintf (s, len + 1, fmt, list);
va_end (list);
} else
strcpy (s, spbuf);
val -> next = client -> env;
client -> env = val;
client -> envc++;
}
int dhcp_option_ev_name (buf, buflen, option)
char *buf;
size_t buflen;
struct option *option;
{
int i;
for (i = 0; option -> name [i]; i++) {
if (i + 1 == buflen)
return 0;
if (option -> name [i] == '-')
buf [i] = '_';
else
buf [i] = option -> name [i];
}
buf [i] = 0;
return 1;
}
void go_daemon ()
{
static int state = 0;
int pid;
/* Don't become a daemon if the user requested otherwise. */
if (no_daemon) {
write_client_pid_file ();
return;
}
/* Only do it once. */
if (state)
return;
state = 1;
/* Stop logging to stderr... */
log_perror = 0;
/* Become a daemon... */
if ((pid = fork ()) < 0)
log_fatal ("Can't fork daemon: %m");
else if (pid)
exit (0);
/* Become session leader and get pid... */
pid = setsid ();
/* Close standard I/O descriptors. */
close(0);
close(1);
close(2);
write_client_pid_file ();
}
void write_client_pid_file ()
{
FILE *pf;
int pfdesc;
pfdesc = open (path_dhclient_pid, O_CREAT | O_TRUNC | O_WRONLY, 0644);
if (pfdesc < 0) {
log_error ("Can't create %s: %m", path_dhclient_pid);
return;
}
pf = fdopen (pfdesc, "w");
if (!pf)
log_error ("Can't fdopen %s: %m", path_dhclient_pid);
else {
fprintf (pf, "%ld\n", (long)getpid ());
fclose (pf);
}
}
void client_location_changed ()
{
struct interface_info *ip;
struct client_state *client;
for (ip = interfaces; ip; ip = ip -> next) {
for (client = ip -> client; client; client = client -> next) {
switch (client -> state) {
case S_SELECTING:
cancel_timeout (send_discover, client);
break;
case S_BOUND:
cancel_timeout (state_bound, client);
break;
case S_REBOOTING:
case S_REQUESTING:
case S_RENEWING:
cancel_timeout (send_request, client);
break;
case S_INIT:
case S_REBINDING:
break;
}
client -> state = S_INIT;
state_reboot (client);
}
}
}
void do_release(client)
struct client_state *client;
{
struct data_string ds;
struct option_cache *oc;
/* make_request doesn't initialize xid because it normally comes
from the DHCPDISCOVER, but we haven't sent a DHCPDISCOVER,
so pick an xid now. */
client -> xid = random ();
/* is there even a lease to release? */
if (client -> active) {
/* Make a DHCPRELEASE packet, and set appropriate per-interface
flags. */
make_release (client, client -> active);
memset (&ds, 0, sizeof ds);
oc = lookup_option (&dhcp_universe,
client -> active -> options,
DHO_DHCP_SERVER_IDENTIFIER);
if (oc &&
evaluate_option_cache (&ds, (struct packet *)0,
(struct lease *)0,
(struct option_state *)0,
client -> active -> options,
&global_scope, oc, MDL)) {
if (ds.len > 3) {
memcpy (client -> destination.iabuf,
ds.data, 4);
client -> destination.len = 4;
} else
client -> destination = iaddr_broadcast;
} else
client -> destination = iaddr_broadcast;
client -> first_sending = cur_time;
client -> interval = client -> config -> initial_interval;
/* Zap the medium list... */
client -> medium = (struct string_list *)0;
/* Send out the first and only DHCPRELEASE packet. */
send_release (client);
/* Do the client script RELEASE operation. */
script_init (client,
"RELEASE", (struct string_list *)0);
if (client -> alias)
script_write_params (client, "alias_",
client -> alias);
script_go (client);
}
/* remove the timeouts for this client */
cancel_timeout (0, client);
}
int dhclient_interface_shutdown_hook (struct interface_info *interface)
{
do_release (interface -> client);
return 1;
}
int dhclient_interface_discovery_hook (struct interface_info *tmp)
{
struct interface_info *last, *ip;
/* See if we can find the client from dummy_interfaces */
last = 0;
for (ip = dummy_interfaces; ip; ip = ip -> next) {
if (!strcmp (ip -> name, tmp -> name)) {
/* Remove from dummy_interfaces */
if (last) {
ip = (struct interface_info *)0;
interface_reference (&ip, last -> next, MDL);
interface_dereference (&last -> next, MDL);
if (ip -> next) {
interface_reference (&last -> next,
ip -> next, MDL);
interface_dereference (&ip -> next,
MDL);
}
} else {
ip = (struct interface_info *)0;
interface_reference (&ip,
dummy_interfaces, MDL);
interface_dereference (&dummy_interfaces, MDL);
if (ip -> next) {
interface_reference (&dummy_interfaces,
ip -> next, MDL);
interface_dereference (&ip -> next,
MDL);
}
}
/* Copy "client" to tmp */
if (ip -> client) {
tmp -> client = ip -> client;
tmp -> client -> interface = tmp;
}
interface_dereference (&ip, MDL);
break;
}
last = ip;
}
return 1;
}
/* The client should never receive a relay agent information option,
so if it does, log it and discard it. */
int parse_agent_information_option (packet, len, data)
struct packet *packet;
int len;
u_int8_t *data;
{
log_info ("relay agent information option received.");
return 1;
}
/* The client never sends relay agent information options. */
unsigned cons_agent_information_options (cfg_options, outpacket,
agentix, length)
struct option_state *cfg_options;
struct dhcp_packet *outpacket;
unsigned agentix;
unsigned length;
{
return length;
}
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