mir/isc-dhcp
2
0
Fork 0
mirror of https://gitlab.isc.org/isc-projects/dhcp synced 2025-08-22 18:07:25 +00:00
Code Issues Releases Wiki Activity

[master] Added configuration parameter, ping-cltt-secs (v4 operation only)

Browse Source 
Merges in rt36283.
This commit is contained in:
Thomas Markwalder 2018-09-26 11:10:16 -04:00
parent cce04313d9
commit a5b21e16ff
5 changed files with 238 additions and 112 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
RELNOTES
View File

@ -88,7 +88,13 @@ Consortium. This product includes cryptographic software written
by Eric Young (eay@cryptsoft.com). by Eric Young (eay@cryptsoft.com).
Changes since 4.4.1 (New Features) Changes since 4.4.1 (New Features)
- none
- A new configuration parameter, ping-cltt-secs (v4 operation only), has
been added to allow the user to specify the number of seconds that must
elapse since CLTT before a ping check is conducted. Prior to this, the
value was hard coded at 60 seconds. Please see the server man pages for
a more detailed discussion.
[ISC-Bugs #36283]
Changes since 4.4.1 (Bug Fixes) Changes since 4.4.1 (Bug Fixes)
@ -100,7 +106,6 @@ by Eric Young (eay@cryptsoft.com).
Changes since 4.4.0 (New Features) Changes since 4.4.0 (New Features)
- none - none
Changes since 4.4.0 (Bug Fixes) Changes since 4.4.0 (Bug Fixes)
- A delayed-ack value of 0 (the default), now correctly disables the delayed - A delayed-ack value of 0 (the default), now correctly disables the delayed

6
includes/dhcpd.h
View File

@ -815,11 +815,17 @@ struct lease_state {
#define SV_RELEASE_ON_ROAM 95 #define SV_RELEASE_ON_ROAM 95
#define SV_LOCAL_ADDRESS6 96 #define SV_LOCAL_ADDRESS6 96
#define SV_BIND_LOCAL_ADDRESS6 97 #define SV_BIND_LOCAL_ADDRESS6 97
#define SV_PING_CLTT_SECS 98
#if !defined (DEFAULT_PING_TIMEOUT) #if !defined (DEFAULT_PING_TIMEOUT)
# define DEFAULT_PING_TIMEOUT 1 # define DEFAULT_PING_TIMEOUT 1
#endif #endif
#if !defined (DEFAULT_PING_CLTT_SECS)
# define DEFAULT_PING_CLTT_SECS 60 /* in seconds */
#endif
#if !defined (DEFAULT_DELAYED_ACK) #if !defined (DEFAULT_DELAYED_ACK)
# define DEFAULT_DELAYED_ACK 0 /* default 0 disables delayed acking */ # define DEFAULT_DELAYED_ACK 0 /* default 0 disables delayed acking */
#endif #endif

304
server/dhcp.c
View File

@ -33,9 +33,15 @@
static void maybe_return_agent_options(struct packet *packet, static void maybe_return_agent_options(struct packet *packet,
struct option_state *options); struct option_state *options);
static int reuse_lease (struct packet* packet, struct lease* new_lease, static int reuse_lease (struct packet* packet, struct lease* new_lease,
struct lease* lease, struct lease_state *state, struct lease* lease, struct lease_state *state,
int offer); int offer, int* same_client);
static int do_ping_check(struct packet* packet, struct lease_state* state,
struct lease* lease, TIME original_cltt,
int same_client);
#if defined(DHCPv6) && defined(DHCP4o6) #if defined(DHCPv6) && defined(DHCP4o6)
static int locate_network6(struct packet *packet); static int locate_network6(struct packet *packet);
#endif #endif
@ -64,7 +70,7 @@ static int site_code_min;
static int find_min_site_code(struct universe *); static int find_min_site_code(struct universe *);
static isc_result_t lowest_site_code(const void *, unsigned, void *); static isc_result_t lowest_site_code(const void *, unsigned, void *);
static const char *dhcp_type_names [] = { static const char *dhcp_type_names [] = {
"DHCPDISCOVER", "DHCPDISCOVER",
"DHCPOFFER", "DHCPOFFER",
"DHCPREQUEST", "DHCPREQUEST",
@ -97,13 +103,13 @@ dhcp (struct packet *packet) {
if (!locate_network(packet) && if (!locate_network(packet) &&
packet->packet_type != DHCPREQUEST && packet->packet_type != DHCPREQUEST &&
packet->packet_type != DHCPINFORM && packet->packet_type != DHCPINFORM &&
packet->packet_type != DHCPLEASEQUERY) { packet->packet_type != DHCPLEASEQUERY) {
const char *s; const char *s;
char typebuf[32]; char typebuf[32];
errmsg = "unknown network segment"; errmsg = "unknown network segment";
bad_packet: bad_packet:
if (packet->packet_type > 0 && if (packet->packet_type > 0 &&
packet->packet_type <= dhcp_type_name_max) { packet->packet_type <= dhcp_type_name_max) {
s = dhcp_type_names[packet->packet_type - 1]; s = dhcp_type_names[packet->packet_type - 1];
@ -112,7 +118,7 @@ dhcp (struct packet *packet) {
sprintf(typebuf, "type %d", packet->packet_type); sprintf(typebuf, "type %d", packet->packet_type);
s = typebuf; s = typebuf;
} }
#if defined(DHCPv6) && defined(DHCP4o6) #if defined(DHCPv6) && defined(DHCP4o6)
if (dhcpv4_over_dhcpv6 && (packet->dhcp4o6_response != NULL)) { if (dhcpv4_over_dhcpv6 && (packet->dhcp4o6_response != NULL)) {
log_info("DHCP4o6 %s from %s via %s: %s", s, log_info("DHCP4o6 %s from %s via %s: %s", s,
@ -387,7 +393,7 @@ void dhcpdiscover (packet, ms_nulltp)
/* If we didn't find a lease, try to allocate one... */ /* If we didn't find a lease, try to allocate one... */
if (!lease) { if (!lease) {
if (!allocate_lease (&lease, packet, if (!allocate_lease (&lease, packet,
packet -> shared_network -> pools, packet -> shared_network -> pools,
&peer_has_leases)) { &peer_has_leases)) {
if (peer_has_leases) if (peer_has_leases)
log_error ("%s: peer holds all free leases", log_error ("%s: peer holds all free leases",
@ -710,7 +716,7 @@ void dhcprequest (packet, ms_nulltp, ip_lease)
(packet -> raw -> ciaddr.s_addr && (packet -> raw -> ciaddr.s_addr &&
packet -> raw -> giaddr.s_addr) || packet -> raw -> giaddr.s_addr) ||
(have_requested_addr && !packet -> raw -> ciaddr.s_addr)) { (have_requested_addr && !packet -> raw -> ciaddr.s_addr)) {
/* If we don't know where it came from but we do know /* If we don't know where it came from but we do know
where it claims to have come from, it didn't come where it claims to have come from, it didn't come
from there. */ from there. */
@ -913,7 +919,7 @@ void dhcprelease (packet, ms_nulltp)
/* If we found a lease, release it. */ /* If we found a lease, release it. */
if (lease && lease -> ends > cur_time) { if (lease && lease -> ends > cur_time) {
release_lease (lease, packet); release_lease (lease, packet);
} }
log_info ("%s", msgbuf); log_info ("%s", msgbuf);
#if defined(FAILOVER_PROTOCOL) #if defined(FAILOVER_PROTOCOL)
out: out:
@ -1167,7 +1173,7 @@ void dhcpinform (packet, ms_nulltp)
relay_port = dhcp_check_relayport(packet); relay_port = dhcp_check_relayport(packet);
#endif #endif
/* Find the subnet that the client is on. /* Find the subnet that the client is on.
* CC: Do the link selection / subnet selection * CC: Do the link selection / subnet selection
*/ */
@ -1247,7 +1253,7 @@ void dhcpinform (packet, ms_nulltp)
option_state_dereference(&options, MDL); option_state_dereference(&options, MDL);
return; return;
} }
memset(&outgoing, 0, sizeof outgoing); memset(&outgoing, 0, sizeof outgoing);
memset(&raw, 0, sizeof raw); memset(&raw, 0, sizeof raw);
outgoing.raw = &raw; outgoing.raw = &raw;
@ -1265,8 +1271,8 @@ void dhcpinform (packet, ms_nulltp)
struct lease* cip_lease = NULL; struct lease* cip_lease = NULL;
find_lease_by_ip_addr (&cip_lease, cip, MDL); find_lease_by_ip_addr (&cip_lease, cip, MDL);
/* Overlay with pool options if ciaddr mapped to a lease. */ /* Overlay with pool options if ciaddr mapped to a lease. */
if (cip_lease) { if (cip_lease) {
if (cip_lease->pool && cip_lease->pool->group) { if (cip_lease->pool && cip_lease->pool->group) {
execute_statements_in_scope( execute_statements_in_scope(
@ -1281,7 +1287,7 @@ void dhcpinform (packet, ms_nulltp)
lease_dereference (&cip_lease, MDL); lease_dereference (&cip_lease, MDL);
} }
} }
/* Execute statements in the class scopes. */ /* Execute statements in the class scopes. */
for (i = packet->class_count; i > 0; i--) { for (i = packet->class_count; i > 0; i--) {
execute_statements_in_scope(NULL, packet, NULL, NULL, execute_statements_in_scope(NULL, packet, NULL, NULL,
@ -1293,7 +1299,7 @@ void dhcpinform (packet, ms_nulltp)
} }
/* /*
* Process host declarations during DHCPINFORM, * Process host declarations during DHCPINFORM,
* Try to find a matching host declaration by cli ID or HW addr. * Try to find a matching host declaration by cli ID or HW addr.
* *
* Look through the host decls for one that matches the * Look through the host decls for one that matches the
@ -1436,7 +1442,7 @@ void dhcpinform (packet, ms_nulltp)
if (hp) if (hp)
host_dereference (&hp, MDL); host_dereference (&hp, MDL);
} }
#if defined (DEBUG_INFORM_HOST) #if defined (DEBUG_INFORM_HOST)
/* Hmm..: what when there is a host with a fixed-address, /* Hmm..: what when there is a host with a fixed-address,
* that matches by hw or id, but the fixed-addresses * that matches by hw or id, but the fixed-addresses
@ -1465,7 +1471,7 @@ void dhcpinform (packet, ms_nulltp)
} }
/* CC: end of host entry processing.... */ /* CC: end of host entry processing.... */
/* Figure out the filename. */ /* Figure out the filename. */
memset (&d1, 0, sizeof d1); memset (&d1, 0, sizeof d1);
oc = lookup_option (&server_universe, options, SV_FILENAME); oc = lookup_option (&server_universe, options, SV_FILENAME);
@ -1477,7 +1483,7 @@ void dhcpinform (packet, ms_nulltp)
i = d1.len; i = d1.len;
if (i >= sizeof(raw.file)) { if (i >= sizeof(raw.file)) {
log_info("file name longer than packet field " log_info("file name longer than packet field "
"truncated - field: %lu name: %d %.*s", "truncated - field: %lu name: %d %.*s",
(unsigned long)sizeof(raw.file), i, (unsigned long)sizeof(raw.file), i,
(int)i, d1.data); (int)i, d1.data);
i = sizeof(raw.file); i = sizeof(raw.file);
@ -1497,7 +1503,7 @@ void dhcpinform (packet, ms_nulltp)
i = d1.len; i = d1.len;
if (i >= sizeof(raw.sname)) { if (i >= sizeof(raw.sname)) {
log_info("server name longer than packet field " log_info("server name longer than packet field "
"truncated - field: %lu name: %d %.*s", "truncated - field: %lu name: %d %.*s",
(unsigned long)sizeof(raw.sname), i, (unsigned long)sizeof(raw.sname), i,
(int)i, d1.data); (int)i, d1.data);
i = sizeof(raw.sname); i = sizeof(raw.sname);
@ -1808,7 +1814,7 @@ void nak_lease (packet, cip, network_group)
&i, 0, MDL); &i, 0, MDL);
save_option (&dhcp_universe, options, oc); save_option (&dhcp_universe, options, oc);
option_cache_dereference (&oc, MDL); option_cache_dereference (&oc, MDL);
#if defined(RELAY_PORT) #if defined(RELAY_PORT)
relay_port = dhcp_check_relayport(packet); relay_port = dhcp_check_relayport(packet);
#endif #endif
@ -2180,8 +2186,7 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
TIME default_lease_time; TIME default_lease_time;
struct option_cache *oc; struct option_cache *oc;
isc_result_t result; isc_result_t result;
TIME ping_timeout; TIME original_cltt;
TIME lease_cltt;
struct in_addr from; struct in_addr from;
TIME remaining_time; TIME remaining_time;
struct iaddr cip; struct iaddr cip;
@ -2190,18 +2195,18 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
isc_boolean_t enqueue = ISC_FALSE; isc_boolean_t enqueue = ISC_FALSE;
#endif #endif
int use_old_lease = 0; int use_old_lease = 0;
int same_client = 0;
unsigned i, j; unsigned i, j;
int s1; int s1;
int ignorep; int ignorep;
struct timeval tv;
/* If we're already acking this lease, don't do it again. */ /* If we're already acking this lease, don't do it again. */
if (lease -> state) if (lease -> state)
return; return;
/* Save original cltt for comparison later. */ /* Save original cltt for comparison later. */
lease_cltt = lease->cltt; original_cltt = lease->cltt;
/* If the lease carries a host record, remember it. */ /* If the lease carries a host record, remember it. */
if (hp) if (hp)
@ -2379,7 +2384,7 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
} while (1); } while (1);
} }
} }
/* Make sure this packet satisfies the configured minimum /* Make sure this packet satisfies the configured minimum
number of seconds. */ number of seconds. */
@ -2493,7 +2498,7 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
if (host) if (host)
host_dereference (&host, MDL); host_dereference (&host, MDL);
return; return;
} }
/* Drop the request if it's not allowed for this client. */ /* Drop the request if it's not allowed for this client. */
if (!offer && if (!offer &&
@ -2511,7 +2516,7 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
if (host) if (host)
host_dereference (&host, MDL); host_dereference (&host, MDL);
return; return;
} }
/* Drop the request if booting is specifically denied. */ /* Drop the request if booting is specifically denied. */
oc = lookup_option (&server_universe, state -> options, oc = lookup_option (&server_universe, state -> options,
@ -2633,7 +2638,7 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
host_dereference (&host, MDL); host_dereference (&host, MDL);
return; return;
} }
/* Use the ip address of the lease that we finally found in /* Use the ip address of the lease that we finally found in
the database. */ the database. */
lt -> ip_addr = lease -> ip_addr; lt -> ip_addr = lease -> ip_addr;
@ -2740,7 +2745,7 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
if (lease_time < 0 /* XXX */ if (lease_time < 0 /* XXX */
|| lease_time > max_lease_time) || lease_time > max_lease_time)
lease_time = max_lease_time; lease_time = max_lease_time;
min_lease_time = DEFAULT_MIN_LEASE_TIME; min_lease_time = DEFAULT_MIN_LEASE_TIME;
if (min_lease_time > max_lease_time) if (min_lease_time > max_lease_time)
min_lease_time = max_lease_time; min_lease_time = max_lease_time;
@ -2823,7 +2828,7 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
check_pool_threshold(packet, lease, state); check_pool_threshold(packet, lease, state);
/* a client requests an address which is not yet active*/ /* a client requests an address which is not yet active*/
if (lease->pool && lease->pool->valid_from && if (lease->pool && lease->pool->valid_from &&
cur_time < lease->pool->valid_from) { cur_time < lease->pool->valid_from) {
/* NAK leases before pool activation date */ /* NAK leases before pool activation date */
cip.len = 4; cip.len = 4;
@ -2834,7 +2839,7 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
if (host) if (host)
host_dereference (&host, MDL); host_dereference (&host, MDL);
return; return;
} }
/* CC: /* CC:
@ -2852,7 +2857,7 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
A min-lease-time of 6 seconds effectively switches over A min-lease-time of 6 seconds effectively switches over
all clients in this pool very quickly. all clients in this pool very quickly.
*/ */
if (lease->pool && lease->pool->valid_until) { if (lease->pool && lease->pool->valid_until) {
if (cur_time >= lease->pool->valid_until) { if (cur_time >= lease->pool->valid_until) {
/* NAK leases after pool expiration date */ /* NAK leases after pool expiration date */
@ -2869,7 +2874,7 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
if (lease_time > remaining_time) if (lease_time > remaining_time)
lease_time = remaining_time; lease_time = remaining_time;
} }
if (lease_time < min_lease_time) { if (lease_time < min_lease_time) {
if (min_lease_time) if (min_lease_time)
lease_time = min_lease_time; lease_time = min_lease_time;
@ -3008,7 +3013,7 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
!evaluate_boolean_option_cache(&ignorep, packet, lease, NULL, !evaluate_boolean_option_cache(&ignorep, packet, lease, NULL,
packet->options, state->options, packet->options, state->options,
&lease->scope, oc, MDL)) { &lease->scope, oc, MDL)) {
/* Record the uid, if given... */ /* Record the uid, if given... */
oc = lookup_option (&dhcp_universe, packet -> options, oc = lookup_option (&dhcp_universe, packet -> options,
DHO_DHCP_CLIENT_IDENTIFIER); DHO_DHCP_CLIENT_IDENTIFIER);
@ -3194,7 +3199,8 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
/* If dhcp-cache-threshold is enabled, see if "lease" can /* If dhcp-cache-threshold is enabled, see if "lease" can
* be reused. */ * be reused. */
use_old_lease = reuse_lease(packet, lt, lease, state, offer); use_old_lease = reuse_lease(packet, lt, lease, state, offer,
&same_client);
if (use_old_lease == 1) { if (use_old_lease == 1) {
commit = 0; commit = 0;
} }
@ -3434,7 +3440,7 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
} }
/* Use the name of the host declaration if there is one /* Use the name of the host declaration if there is one
and no hostname has otherwise been provided, and if the and no hostname has otherwise been provided, and if the
use-host-decl-name flag is set. */ use-host-decl-name flag is set. */
use_host_decl_name(packet, lease, state->options); use_host_decl_name(packet, lease, state->options);
@ -3452,9 +3458,9 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
lookup_option (&server_universe, state->options, j), MDL)) { lookup_option (&server_universe, state->options, j), MDL)) {
struct in_addr ia; struct in_addr ia;
struct hostent *h; struct hostent *h;
memcpy (&ia, lease -> ip_addr.iabuf, 4); memcpy (&ia, lease -> ip_addr.iabuf, 4);
h = gethostbyaddr ((char *)&ia, sizeof ia, AF_INET); h = gethostbyaddr ((char *)&ia, sizeof ia, AF_INET);
if (!h) if (!h)
log_error ("No hostname for %s", inet_ntoa (ia)); log_error ("No hostname for %s", inet_ntoa (ia));
@ -3501,7 +3507,7 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
save_option (&dhcp_universe, save_option (&dhcp_universe,
state -> options, oc); state -> options, oc);
} }
option_cache_dereference (&oc, MDL); option_cache_dereference (&oc, MDL);
} }
} }
} }
@ -3560,64 +3566,134 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
/* Hang the packet off the lease state. */ /* Hang the packet off the lease state. */
packet_reference (&lease -> state -> packet, packet, MDL); packet_reference (&lease -> state -> packet, packet, MDL);
/* If this is a DHCPOFFER, ping the lease address before actually /* If this is a DHCPOFFER, send a ping (if appropriate) to the
sending the offer. */ * lease address before actually we send the offer. */
if (offer == DHCPOFFER && !(lease -> flags & STATIC_LEASE) && if ((offer == DHCPOFFER) &&
(((cur_time - lease_cltt) > 60) || do_ping_check(packet, state, lease, original_cltt, same_client)) {
(lease->binding_state == FTS_ABANDONED)) &&
(!(oc = lookup_option (&server_universe, state -> options,
SV_PING_CHECKS)) ||
evaluate_boolean_option_cache (&ignorep, packet, lease,
(struct client_state *)0,
packet -> options,
state -> options,
&lease -> scope, oc, MDL))) {
icmp_echorequest (&lease -> ip_addr);
/* Determine whether to use configured or default ping timeout.
*/
if ((oc = lookup_option (&server_universe, state -> options,
SV_PING_TIMEOUT)) &&
evaluate_option_cache (&d1, packet, lease, NULL,
packet -> options,
state -> options,
&lease -> scope, oc, MDL)) {
if (d1.len == sizeof (u_int32_t))
ping_timeout = getULong (d1.data);
else
ping_timeout = DEFAULT_PING_TIMEOUT;
data_string_forget (&d1, MDL);
} else
ping_timeout = DEFAULT_PING_TIMEOUT;
#ifdef DEBUG
log_debug ("Ping timeout: %ld", (long)ping_timeout);
#endif
/*
* Set a timeout for 'ping-timeout' seconds from NOW, including
* current microseconds. As ping-timeout defaults to 1, the
* exclusion of current microseconds causes a value somewhere
* /between/ zero and one.
*/
tv.tv_sec = cur_tv.tv_sec + ping_timeout;
tv.tv_usec = cur_tv.tv_usec;
add_timeout (&tv, lease_ping_timeout, lease,
(tvref_t)lease_reference,
(tvunref_t)lease_dereference);
++outstanding_pings; ++outstanding_pings;
} else { } else {
lease->cltt = cur_time; lease->cltt = cur_time;
#if defined(DELAYED_ACK) #if defined(DELAYED_ACK)
if (enqueue) if (enqueue)
delayed_ack_enqueue(lease); delayed_ack_enqueue(lease);
else else
#endif #endif
dhcp_reply(lease); dhcp_reply(lease);
} }
} }
/*
* \brief Sends a ping to the lease ip_addr when appropriate
*
* A ping will be sent if all of the following are true:
*
* 1. Ping checks are enabled
* 2. The lease is neither active nor static
* 3. Any of the following is true:
* a. The lease state is ABANDONED
* b. This is the first offer of this lease (CLTT = 0)
* c. The lease is being offered to a client other than its previous
* owner
* d. The lease is being offered to its previous owner and more than
* cltt-secs have elapsed since CLTT of the original lease.
*
* \param packet inbound packet received from the client
* \param state lease options state
* \param lease lease to be offered (if one)
* \param original_cltt CLTT of the original lease
* \param same_client flag indicating if the client to be offered the
* lease is its previous owner
* \return Returns 1 if ping has been sent, 0 otherwise
*/
int do_ping_check(struct packet* packet, struct lease_state* state,
struct lease* lease, TIME original_cltt,
int same_client) {
TIME ping_timeout = DEFAULT_PING_TIMEOUT;
struct option_cache *oc = NULL;
struct data_string ds;
struct timeval tv;
int ignorep;
// Don't go any further if lease is active or static.
if (lease->binding_state == FTS_ACTIVE || lease->flags & STATIC_LEASE) {
return (0);
}
// If pings aren't enabled, punt.
oc = lookup_option (&server_universe, state -> options, SV_PING_CHECKS);
if (oc &&
!(evaluate_boolean_option_cache (&ignorep, packet, lease,
0, packet->options, state->options,
&lease->scope, oc, MDL))) {
return (0);
}
// If it's not the first time for the same client and not an
// abandoned lease, we need to check the cltt threshold
if (same_client && original_cltt &&
lease->binding_state != FTS_ABANDONED) {
TIME cltt_secs = DEFAULT_PING_CLTT_SECS;
memset(&ds, 0, sizeof(ds));
oc = lookup_option (&server_universe, state->options,
SV_PING_CLTT_SECS);
if (oc &&
(evaluate_option_cache (&ds, packet, lease, 0,
packet->options, state->options,
&lease->scope, oc, MDL))) {
if (ds.len == sizeof (u_int32_t)) {
cltt_secs = getULong (ds.data);
}
data_string_forget (&ds, MDL);
}
// Punt if it is too soon.
if (cur_time - original_cltt < cltt_secs) {
return (0);
}
}
// Send the ping.
icmp_echorequest (&lease->ip_addr);
/* Determine whether to use configured or default ping timeout. */
memset(&ds, 0, sizeof(ds));
oc = lookup_option (&server_universe, state->options, SV_PING_TIMEOUT);
if (oc &&
(evaluate_option_cache (&ds, packet, lease, 0,
packet->options, state->options,
&lease->scope, oc, MDL))) {
if (ds.len == sizeof (u_int32_t)) {
ping_timeout = getULong (ds.data);
}
data_string_forget (&ds, MDL);
}
#ifdef DEBUG
log_debug ("Pinging:%s, state: %d, same client? %s, "
" orig_cltt %s, elasped: %ld" ,
piaddr(lease->ip_addr),
lease->binding_state,
(same_client ? "y" : "n"),
(original_cltt ? print_time(original_cltt) : "0"),
(original_cltt ? (long)(cur_time - original_cltt) : 0));
#endif
/*
* Set a timeout for 'ping-timeout' seconds from NOW, including
* current microseconds. As ping-timeout defaults to 1, the
* exclusion of current microseconds causes a value somewhere
* /between/ zero and one.
*/
tv.tv_sec = cur_tv.tv_sec + ping_timeout;
tv.tv_usec = cur_tv.tv_usec;
add_timeout (&tv, lease_ping_timeout, lease, (tvref_t)lease_reference,
(tvunref_t)lease_dereference);
return (1);
}
#if defined(DELAYED_ACK) #if defined(DELAYED_ACK)
/* /*
@ -3634,7 +3710,7 @@ delayed_ack_enqueue(struct lease *lease)
{ {
struct leasequeue *q; struct leasequeue *q;
if (!write_lease(lease)) if (!write_lease(lease))
return; return;
if (free_ackqueue) { if (free_ackqueue) {
q = free_ackqueue; q = free_ackqueue;
@ -3650,7 +3726,7 @@ delayed_ack_enqueue(struct lease *lease)
lease_reference(&q->lease, lease, MDL); lease_reference(&q->lease, lease, MDL);
q->next = ackqueue_head; q->next = ackqueue_head;
ackqueue_head = q; ackqueue_head = q;
if (!ackqueue_tail) if (!ackqueue_tail)
ackqueue_tail = q; ackqueue_tail = q;
else else
q->next->prev = q; q->next->prev = q;
@ -3723,7 +3799,7 @@ delayed_acks_timer(void *foo)
*/ */
/* process from bottom to retain packet order */ /* process from bottom to retain packet order */
for (ack = ackqueue_tail ; ack ; ack = p) { for (ack = ackqueue_tail ; ack ; ack = p) {
p = ack->prev; p = ack->prev;
#if defined(FAILOVER_PROTOCOL) #if defined(FAILOVER_PROTOCOL)
@ -3762,7 +3838,7 @@ void
relinquish_ackqueue(void) relinquish_ackqueue(void)
{ {
struct leasequeue *q, *n; struct leasequeue *q, *n;
for (q = ackqueue_head ; q ; q = n) { for (q = ackqueue_head ; q ; q = n) {
n = q->next; n = q->next;
dfree(q, MDL); dfree(q, MDL);
@ -3811,9 +3887,9 @@ void dhcp_reply (lease)
if (sizeof raw.file > state -> filename.len) if (sizeof raw.file > state -> filename.len)
memset (&raw.file [state -> filename.len], 0, memset (&raw.file [state -> filename.len], 0,
(sizeof raw.file) - state -> filename.len); (sizeof raw.file) - state -> filename.len);
else else
log_info("file name longer than packet field " log_info("file name longer than packet field "
"truncated - field: %lu name: %d %.*s", "truncated - field: %lu name: %d %.*s",
(unsigned long)sizeof(raw.file), (unsigned long)sizeof(raw.file),
state->filename.len, (int)state->filename.len, state->filename.len, (int)state->filename.len,
state->filename.data); state->filename.data);
@ -3830,9 +3906,9 @@ void dhcp_reply (lease)
if (sizeof raw.sname > state -> server_name.len) if (sizeof raw.sname > state -> server_name.len)
memset (&raw.sname [state -> server_name.len], 0, memset (&raw.sname [state -> server_name.len], 0,
(sizeof raw.sname) - state -> server_name.len); (sizeof raw.sname) - state -> server_name.len);
else else
log_info("server name longer than packet field " log_info("server name longer than packet field "
"truncated - field: %lu name: %d %.*s", "truncated - field: %lu name: %d %.*s",
(unsigned long)sizeof(raw.sname), (unsigned long)sizeof(raw.sname),
state->server_name.len, state->server_name.len,
(int)state->server_name.len, (int)state->server_name.len,
@ -4121,7 +4197,7 @@ int find_lease (struct lease **lp,
cip.len = 4; cip.len = 4;
memcpy (cip.iabuf, d1.data, cip.len); memcpy (cip.iabuf, d1.data, cip.len);
data_string_forget (&d1, MDL); data_string_forget (&d1, MDL);
} else } else
cip.len = 0; cip.len = 0;
} }
@ -4828,7 +4904,7 @@ int mockup_lease (struct lease **lp, struct packet *packet,
{ {
struct lease *lease = (struct lease *)0; struct lease *lease = (struct lease *)0;
struct host_decl *rhp = (struct host_decl *)0; struct host_decl *rhp = (struct host_decl *)0;
if (lease_allocate (&lease, MDL) != ISC_R_SUCCESS) if (lease_allocate (&lease, MDL) != ISC_R_SUCCESS)
return 0; return 0;
if (host_reference (&rhp, hp, MDL) != ISC_R_SUCCESS) { if (host_reference (&rhp, hp, MDL) != ISC_R_SUCCESS) {
@ -4908,7 +4984,7 @@ int allocate_lease (struct lease **lp, struct packet *packet,
/* /*
* In normal operation, we never want to touch * In normal operation, we never want to touch
* the peer's leases. In partner-down * the peer's leases. In partner-down
* operation, we need to be able to pick up * operation, we need to be able to pick up
* the peer's leases after STOS+MCLT. * the peer's leases after STOS+MCLT.
*/ */
@ -5069,7 +5145,7 @@ int permitted (packet, permit_list)
!packet -> packet_type) !packet -> packet_type)
return 1; return 1;
break; break;
case permit_class: case permit_class:
for (i = 0; i < packet -> class_count; i++) { for (i = 0; i < packet -> class_count; i++) {
if (p -> class == packet -> classes [i]) if (p -> class == packet -> classes [i])
@ -5340,8 +5416,8 @@ get_server_source_address(struct in_addr *from,
option_num = DHO_DHCP_SERVER_IDENTIFIER; option_num = DHO_DHCP_SERVER_IDENTIFIER;
oc = lookup_option(&dhcp_universe, options, option_num); oc = lookup_option(&dhcp_universe, options, option_num);
if (oc != NULL) { if (oc != NULL) {
if (evaluate_option_cache(&d, packet, NULL, NULL, if (evaluate_option_cache(&d, packet, NULL, NULL,
packet->options, options, packet->options, options,
&global_scope, oc, MDL)) { &global_scope, oc, MDL)) {
if (d.len == sizeof(*from)) { if (d.len == sizeof(*from)) {
found = ISC_TRUE; found = ISC_TRUE;
@ -5376,7 +5452,7 @@ get_server_source_address(struct in_addr *from,
if (make_const_data(&oc->expression, if (make_const_data(&oc->expression,
(unsigned char *)a, sizeof(*a), (unsigned char *)a, sizeof(*a),
0, allocate, MDL)) { 0, allocate, MDL)) {
option_code_hash_lookup(&oc->option, option_code_hash_lookup(&oc->option,
dhcp_universe.code_hash, dhcp_universe.code_hash,
&option_num, 0, MDL); &option_num, 0, MDL);
save_option(&dhcp_universe, out_options, oc); save_option(&dhcp_universe, out_options, oc);
@ -5628,7 +5704,10 @@ void use_host_decl_name(struct packet* packet,
* \param packet inbound packet received from the client * \param packet inbound packet received from the client
* \param new_lease candidate new lease to associate with the client * \param new_lease candidate new lease to associate with the client
* \param lease current lease associated with the client * \param lease current lease associated with the client
* \param options option state to search and update * \param lease_state lease state to search and update
* \param offer type of DHCP response we're building
* \param[out] same_client pointer to int, that will be set to 1 if
* the two leases refer to the same client, 0 if not. Must NOT be null.
* *
* \return 1 if the lease can be reused. * \return 1 if the lease can be reused.
*/ */
@ -5637,7 +5716,8 @@ reuse_lease (struct packet* packet,
struct lease* new_lease, struct lease* new_lease,
struct lease* lease, struct lease* lease,
struct lease_state *state, struct lease_state *state,
int offer) { int offer,
int *same_client) {
int reusable = 0; int reusable = 0;
/* To even consider reuse all of the following must be true: /* To even consider reuse all of the following must be true:
@ -5647,16 +5727,20 @@ reuse_lease (struct packet* packet,
* 4 - the host declaration hasn't changed * 4 - the host declaration hasn't changed
* 5 - the uid hasn't changed * 5 - the uid hasn't changed
* 6 - the hardware address hasn't changed */ * 6 - the hardware address hasn't changed */
/* Check client equality separately so we can pass the result out. */
*same_client =
(((lease->host == new_lease->host) &&
(lease->uid_len == new_lease->uid_len) &&
(memcmp(lease->uid, new_lease->uid, new_lease->uid_len) == 0) &&
(lease->hardware_addr.hlen == new_lease->hardware_addr.hlen) &&
(memcmp(&lease->hardware_addr.hbuf[0],
&new_lease->hardware_addr.hbuf[0],
lease->hardware_addr.hlen) == 0)) ? 1 : 0);
if ((lease->cannot_reuse == 0) && if ((lease->cannot_reuse == 0) &&
(lease->binding_state == FTS_ACTIVE) && (lease->binding_state == FTS_ACTIVE) &&
(new_lease->ddns_cb == NULL) && (new_lease->ddns_cb == NULL) && *same_client) {
(lease->host == new_lease->host) &&
(lease->uid_len == new_lease->uid_len) &&
(memcmp(lease->uid, new_lease->uid, lease->uid_len) == 0) &&
(lease->hardware_addr.hlen == new_lease->hardware_addr.hlen) &&
(memcmp(&lease->hardware_addr.hbuf[0],
&new_lease->hardware_addr.hbuf[0],
lease->hardware_addr.hlen) == 0)) {
int thresh = DEFAULT_CACHE_THRESHOLD; int thresh = DEFAULT_CACHE_THRESHOLD;
struct option_cache* oc = NULL; struct option_cache* oc = NULL;
struct data_string d1; struct data_string d1;

30
server/dhcpd.conf.5
View File

@ -3027,6 +3027,36 @@ checking - if its value is false, no ping check is done.
.RE .RE
.PP .PP
The The
.I ping-cltt-secs
statement
.RS 0.25i
.PP
.B ping-cltt-secs
.I seconds\fR\fB;\fR
.PP
The server will conduct a ping check if all the following conditions are true:
.PP
1. Ping checking is enabled.
.PP
2. The server is responding to a DISCOVER.
.PP
3. The lease to be offered is neither static nor active (i.e. still a valid
lease).
.PP
4. And any of the following are true:
a. This will be the first offer of this lease (CLTT is 0).
b. The lease is being offered to a client other than its previous owner
c. The lease is being offered to its previous owner and more than
\fBping-cltt-secs\fR have elapsed since CLTT of the original lease.
d. The lease was abandoned and the server is attempting to reclaim it.
.PP
The \fBping-cltt-secs\fR statement allows the user to specify the amount of
time that must elaspe after CLTT before a ping check will be conducted.
The default value is sixty seconds.
.RE
.PP
The
.I ping-timeout .I ping-timeout
statement statement
.RS 0.25i .RS 0.25i

1
server/stables.c
View File

@ -291,6 +291,7 @@ static struct option server_options[] = {
{ "release-on-roam", "f", &server_universe, SV_RELEASE_ON_ROAM, 1 }, { "release-on-roam", "f", &server_universe, SV_RELEASE_ON_ROAM, 1 },
{ "local-address6", "6", &server_universe, SV_LOCAL_ADDRESS6, 1 }, { "local-address6", "6", &server_universe, SV_LOCAL_ADDRESS6, 1 },
{ "bind-local-address6", "f", &server_universe, SV_BIND_LOCAL_ADDRESS6, 1 }, { "bind-local-address6", "f", &server_universe, SV_BIND_LOCAL_ADDRESS6, 1 },
{ "ping-cltt-secs", "T", &server_universe, SV_PING_CLTT_SECS, 1 },
{ NULL, NULL, NULL, 0, 0 } { NULL, NULL, NULL, 0, 0 }
}; };