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isc-dhcp/server/dhcpleasequery.c
Thomas Markwalder 0cd94b5ef4 [#64,!35] Restored work 
Restored cummulative work.
2019-11-22 13:39:45 -05:00

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/*
* Copyright (C) 2006-2017 by Internet Systems Consortium, Inc. ("ISC")
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*/
#include "dhcpd.h"
/*
* TODO: RFC4388 specifies that the server SHOULD return the same
* options it would for a DHCREQUEST message, if no Parameter
* Request List option (option 55) is passed. We do not do that.
*
* TODO: RFC4388 specifies the creation of a "non-sensitive options"
* configuration list, and that these SHOULD be returned. We
* have no such list.
*
* TODO: RFC4388 says the server SHOULD use RFC3118, "Authentication
* for DHCP Messages".
*
* TODO: RFC4388 specifies that you SHOULD insure that you cannot be
* DoS'ed by DHCPLEASEQUERY message.
*/
/*
* If you query by hardware address or by client ID, then you may have
* more than one IP address for your query argument. We need to do two
* things:
*
* 1. Find the most recent lease.
* 2. Find all additional IP addresses for the query argument.
*
* We do this by looking through all of the leases associated with a
* given hardware address or client ID. We use the cltt (client last
* transaction time) of the lease, which only has a resolution of one
* second, so we might not actually give the very latest IP.
*/
static struct lease*
next_hw(const struct lease *lease) {
/* INSIST(lease != NULL); */
return lease->n_hw;
}
static struct lease*
next_uid(const struct lease *lease) {
/* INSIST(lease != NULL); */
return lease->n_uid;
}
void
get_newest_lease(struct lease **retval,
struct lease *lease,
struct lease *(*next)(const struct lease *)) {
struct lease *p;
struct lease *newest;
/* INSIST(newest != NULL); */
/* INSIST(next != NULL); */
*retval = NULL;
if (lease == NULL) {
return;
}
newest = lease;
for (p=next(lease); p != NULL; p=next(p)) {
if (newest->binding_state == FTS_ACTIVE) {
if ((p->binding_state == FTS_ACTIVE) &&
(p->cltt > newest->cltt)) {
newest = p;
}
} else {
if (p->ends > newest->ends) {
newest = p;
}
}
}
lease_reference(retval, newest, MDL);
}
static int
get_associated_ips(const struct lease *lease,
struct lease *(*next)(const struct lease *),
const struct lease *newest,
u_int32_t *associated_ips,
unsigned int associated_ips_size) {
const struct lease *p;
int cnt;
/* INSIST(next != NULL); */
/* INSIST(associated_ips != NULL); */
if (lease == NULL) {
return 0;
}
cnt = 0;
for (p=lease; p != NULL; p=next(p)) {
if ((p->binding_state == FTS_ACTIVE) && (p != newest)) {
if (cnt < associated_ips_size) {
memcpy(&associated_ips[cnt],
p->ip_addr.iabuf,
sizeof(associated_ips[cnt]));
}
cnt++;
}
}
return cnt;
}
void
dhcpleasequery(struct packet *packet, int ms_nulltp) {
char msgbuf[256];
char dbg_info[128];
struct iaddr cip;
struct iaddr gip;
struct data_string uid;
struct hardware h;
struct lease *tmp_lease;
struct lease *lease;
int want_associated_ip;
int assoc_ip_cnt;
u_int32_t assoc_ips[40]; /* XXXSK: arbitrary maximum number of IPs */
const int nassoc_ips = sizeof(assoc_ips) / sizeof(assoc_ips[0]);
unsigned char dhcpMsgType;
const char *dhcp_msg_type_name;
struct subnet *subnet;
struct group *relay_group;
struct option_state *options;
struct option_cache *oc;
int allow_leasequery;
int ignorep;
u_int32_t lease_duration;
u_int32_t time_renewal;
u_int32_t time_rebinding;
u_int32_t time_expiry;
u_int32_t client_last_transaction_time;
#if defined(RELAY_PORT)
u_int16_t relay_port = 0;
#endif
struct sockaddr_in to;
struct in_addr siaddr;
struct data_string prl;
struct data_string *prl_ptr;
int i;
struct interface_info *interface;
/* INSIST(packet != NULL); */
/*
* Prepare log information.
*/
snprintf(msgbuf, sizeof(msgbuf),
"DHCPLEASEQUERY from %s", inet_ntoa(packet->raw->giaddr));
/*
* We can't reply if there is no giaddr field.
*/
/*
* Note: this makes DHCPv4-over-DHCPv6 always fail but it should not
* really be a problem because it is not a specified use case
* (or even one that makes sense).
*/
if (!packet->raw->giaddr.s_addr) {
log_info("%s: missing giaddr, ciaddr is %s, no reply sent",
msgbuf, inet_ntoa(packet->raw->ciaddr));
return;
}
/*
* Initially we use the 'giaddr' subnet options scope to determine if
* the giaddr-identified relay agent is permitted to perform a
* leasequery. The subnet is not required, and may be omitted, in
* which case we are essentially interrogating the root options class
* to find a globally permit.
*/
gip.len = sizeof(packet->raw->giaddr);
memcpy(gip.iabuf, &packet->raw->giaddr, sizeof(packet->raw->giaddr));
subnet = NULL;
find_subnet(&subnet, gip, MDL);
if (subnet != NULL)
relay_group = subnet->group;
else
relay_group = root_group;
subnet_dereference(&subnet, MDL);
options = NULL;
if (!option_state_allocate(&options, MDL)) {
log_error("No memory for option state.");
log_info("%s: out of memory, no reply sent", msgbuf);
return;
}
execute_statements_in_scope(NULL, packet, NULL, NULL, packet->options,
options, &global_scope, relay_group,
NULL, NULL);
for (i=packet->class_count-1; i>=0; i--) {
execute_statements_in_scope(NULL, packet, NULL, NULL,
packet->options, options,
&global_scope,
packet->classes[i]->group,
relay_group, NULL);
}
/*
* Because LEASEQUERY has some privacy concerns, default to deny.
*/
allow_leasequery = 0;
/*
* See if we are authorized to do LEASEQUERY.
*/
oc = lookup_option(&server_universe, options, SV_LEASEQUERY);
if (oc != NULL) {
allow_leasequery = evaluate_boolean_option_cache(&ignorep,
packet, NULL, NULL, packet->options,
options, &global_scope, oc, MDL);
}
if (!allow_leasequery) {
log_info("%s: LEASEQUERY not allowed, query ignored", msgbuf);
option_state_dereference(&options, MDL);
return;
}
/*
* Copy out the client IP address.
*/
cip.len = sizeof(packet->raw->ciaddr);
memcpy(cip.iabuf, &packet->raw->ciaddr, sizeof(packet->raw->ciaddr));
/*
* If the client IP address is valid (not all zero), then we
* are looking for information about that IP address.
*/
assoc_ip_cnt = 0;
lease = tmp_lease = NULL;
if (memcmp(cip.iabuf, "\0\0\0", 4)) {
want_associated_ip = 0;
snprintf(dbg_info, sizeof(dbg_info), "IP %s", piaddr(cip));
find_lease_by_ip_addr(&lease, cip, MDL);
} else {
want_associated_ip = 1;
/*
* If the client IP address is all zero, then we will
* either look up by the client identifier (if we have
* one), or by the MAC address.
*/
memset(&uid, 0, sizeof(uid));
if (get_option(&uid,
&dhcp_universe,
packet,
NULL,
NULL,
packet->options,
NULL,
packet->options,
&global_scope,
DHO_DHCP_CLIENT_IDENTIFIER,
MDL)) {
snprintf(dbg_info,
sizeof(dbg_info),
"client-id %s",
print_hex_1(uid.len, uid.data, 60));
find_lease_by_uid(&tmp_lease, uid.data, uid.len, MDL);
data_string_forget(&uid, MDL);
get_newest_lease(&lease, tmp_lease, next_uid);
assoc_ip_cnt = get_associated_ips(tmp_lease,
next_uid,
lease,
assoc_ips,
nassoc_ips);
} else {
if (packet->raw->hlen+1 > sizeof(h.hbuf)) {
log_info("%s: hardware length too long, "
"no reply sent", msgbuf);
option_state_dereference(&options, MDL);
return;
}
h.hlen = packet->raw->hlen + 1;
h.hbuf[0] = packet->raw->htype;
memcpy(&h.hbuf[1],
packet->raw->chaddr,
packet->raw->hlen);
snprintf(dbg_info,
sizeof(dbg_info),
"MAC address %s",
print_hw_addr(h.hbuf[0],
h.hlen - 1,
&h.hbuf[1]));
find_lease_by_hw_addr(&tmp_lease, h.hbuf, h.hlen, MDL);
get_newest_lease(&lease, tmp_lease, next_hw);
assoc_ip_cnt = get_associated_ips(tmp_lease,
next_hw,
lease,
assoc_ips,
nassoc_ips);
}
lease_dereference(&tmp_lease, MDL);
if (lease != NULL) {
memcpy(&packet->raw->ciaddr,
lease->ip_addr.iabuf,
sizeof(packet->raw->ciaddr));
}
/*
* Log if we have too many IP addresses associated
* with this client.
*/
if (want_associated_ip && (assoc_ip_cnt > nassoc_ips)) {
log_info("%d IP addresses associated with %s, "
"only %d sent in reply.",
assoc_ip_cnt, dbg_info, nassoc_ips);
}
}
/*
* We now know the query target too, so can report this in
* our log message.
*/
snprintf(msgbuf, sizeof(msgbuf),
"DHCPLEASEQUERY from %s for %s",
inet_ntoa(packet->raw->giaddr), dbg_info);
/*
* Figure our our return type.
*/
if (lease == NULL) {
dhcpMsgType = DHCPLEASEUNKNOWN;
dhcp_msg_type_name = "DHCPLEASEUNKNOWN";
} else {
if (lease->binding_state == FTS_ACTIVE) {
dhcpMsgType = DHCPLEASEACTIVE;
dhcp_msg_type_name = "DHCPLEASEACTIVE";
} else {
dhcpMsgType = DHCPLEASEUNASSIGNED;
dhcp_msg_type_name = "DHCPLEASEUNASSIGNED";
}
}
/*
* Set options that only make sense if we have an active lease.
*/
if (dhcpMsgType == DHCPLEASEACTIVE)
{
/*
* RFC 4388 uses the PRL to request options for the agent to
* receive that are "about" the client. It is confusing
* because in some cases it wants to know what was sent to
* the client (lease times, adjusted), and in others it wants
* to know information the client sent. You're supposed to
* know this on a case-by-case basis.
*
* "Name servers", "domain name", and the like from the relay
* agent's scope seems less than useful. Our options are to
* restart the option cache from the lease's best point of view
* (execute statements from the lease pool's group), or to
* simply restart the option cache from empty.
*
* I think restarting the option cache from empty best
* approaches RFC 4388's intent; specific options are included.
*/
option_state_dereference(&options, MDL);
if (!option_state_allocate(&options, MDL)) {
log_error("%s: out of memory, no reply sent", msgbuf);
lease_dereference(&lease, MDL);
return;
}
/*
* Set the hardware address fields.
*/
packet->raw->hlen = lease->hardware_addr.hlen - 1;
packet->raw->htype = lease->hardware_addr.hbuf[0];
memcpy(packet->raw->chaddr,
&lease->hardware_addr.hbuf[1],
sizeof(packet->raw->chaddr));
/*
* Set client identifier option.
*/
if (lease->uid_len > 0) {
if (!add_option(options,
DHO_DHCP_CLIENT_IDENTIFIER,
lease->uid,
lease->uid_len)) {
option_state_dereference(&options, MDL);
lease_dereference(&lease, MDL);
log_info("%s: out of memory, no reply sent",
msgbuf);
return;
}
}
/*
* Calculate T1 and T2, the times when the client
* tries to extend its lease on its networking
* address.
* These seem to be hard-coded in ISC DHCP, to 0.5 and
* 0.875 of the lease time.
*/
lease_duration = lease->ends - lease->starts;
time_renewal = lease->starts +
(lease_duration / 2);
time_rebinding = lease->starts +
(lease_duration / 2) +
(lease_duration / 4) +
(lease_duration / 8);
if (time_renewal > cur_time) {
time_renewal = htonl(time_renewal - cur_time);
if (!add_option(options,
DHO_DHCP_RENEWAL_TIME,
&time_renewal,
sizeof(time_renewal))) {
option_state_dereference(&options, MDL);
lease_dereference(&lease, MDL);
log_info("%s: out of memory, no reply sent",
msgbuf);
return;
}
}
if (time_rebinding > cur_time) {
time_rebinding = htonl(time_rebinding - cur_time);
if (!add_option(options,
DHO_DHCP_REBINDING_TIME,
&time_rebinding,
sizeof(time_rebinding))) {
option_state_dereference(&options, MDL);
lease_dereference(&lease, MDL);
log_info("%s: out of memory, no reply sent",
msgbuf);
return;
}
}
if (lease->ends > cur_time) {
time_expiry = htonl(lease->ends - cur_time);
if (!add_option(options,
DHO_DHCP_LEASE_TIME,
&time_expiry,
sizeof(time_expiry))) {
option_state_dereference(&options, MDL);
lease_dereference(&lease, MDL);
log_info("%s: out of memory, no reply sent",
msgbuf);
return;
}
}
/* Supply the Vendor-Class-Identifier. */
if (lease->scope != NULL) {
struct data_string vendor_class;
memset(&vendor_class, 0, sizeof(vendor_class));
if (find_bound_string(&vendor_class, lease->scope,
"vendor-class-identifier")) {
if (!add_option(options,
DHO_VENDOR_CLASS_IDENTIFIER,
(void *)vendor_class.data,
vendor_class.len)) {
option_state_dereference(&options,
MDL);
lease_dereference(&lease, MDL);
log_error("%s: error adding vendor "
"class identifier, no reply "
"sent", msgbuf);
data_string_forget(&vendor_class, MDL);
return;
}
data_string_forget(&vendor_class, MDL);
}
}
/*
* Set the relay agent info.
*
* Note that because agent info is appended without regard
* to the PRL in cons_options(), this will be sent as the
* last option in the packet whether it is listed on PRL or
* not.
*/
if (lease->agent_options != NULL) {
int idx = agent_universe.index;
struct option_chain_head **tmp1 =
(struct option_chain_head **)
&(options->universes[idx]);
struct option_chain_head *tmp2 =
(struct option_chain_head *)
lease->agent_options;
option_chain_head_reference(tmp1, tmp2, MDL);
}
/*
* Set the client last transaction time.
* We check to make sure we have a timestamp. For
* lease files that were saved before running a
* timestamp-aware version of the server, this may
* not be set.
*/
if (lease->cltt != MIN_TIME) {
if (cur_time > lease->cltt) {
client_last_transaction_time =
htonl(cur_time - lease->cltt);
} else {
client_last_transaction_time = htonl(0);
}
if (!add_option(options,
DHO_CLIENT_LAST_TRANSACTION_TIME,
&client_last_transaction_time,
sizeof(client_last_transaction_time))) {
option_state_dereference(&options, MDL);
lease_dereference(&lease, MDL);
log_info("%s: out of memory, no reply sent",
msgbuf);
return;
}
}
/*
* Set associated IPs, if requested and there are some.
*/
if (want_associated_ip && (assoc_ip_cnt > 0)) {
if (!add_option(options,
DHO_ASSOCIATED_IP,
assoc_ips,
assoc_ip_cnt * sizeof(assoc_ips[0]))) {
option_state_dereference(&options, MDL);
lease_dereference(&lease, MDL);
log_info("%s: out of memory, no reply sent",
msgbuf);
return;
}
}
}
/*
* Set the message type.
*/
packet->raw->op = BOOTREPLY;
/*
* Set DHCP message type.
*/
if (!add_option(options,
DHO_DHCP_MESSAGE_TYPE,
&dhcpMsgType,
sizeof(dhcpMsgType))) {
option_state_dereference(&options, MDL);
lease_dereference(&lease, MDL);
log_info("%s: error adding option, no reply sent", msgbuf);
return;
}
/*
* Log the message we've received.
*/
log_info("%s", msgbuf);
/*
* Figure out which address to use to send from.
*/
get_server_source_address(&siaddr, options, options, packet);
/*
* Set up the option buffer.
*/
memset(&prl, 0, sizeof(prl));
oc = lookup_option(&dhcp_universe, options,
DHO_DHCP_PARAMETER_REQUEST_LIST);
if (oc != NULL) {
evaluate_option_cache(&prl,
packet,
NULL,
NULL,
packet->options,
options,
&global_scope,
oc,
MDL);
}
if (prl.len > 0) {
prl_ptr = &prl;
} else {
prl_ptr = NULL;
}
packet->packet_length = cons_options(packet,
packet->raw,
lease,
NULL,
0,
packet->options,
options,
&global_scope,
0,
0,
0,
prl_ptr,
NULL);
data_string_forget(&prl, MDL); /* SK: safe, even if empty */
option_state_dereference(&options, MDL);
lease_dereference(&lease, MDL);
to.sin_family = AF_INET;
#ifdef HAVE_SA_LEN
to.sin_len = sizeof(to);
#endif
memset(to.sin_zero, 0, sizeof(to.sin_zero));
#if defined(RELAY_PORT)
relay_port = dhcp_check_relayport(packet);
#endif
/*
* Leasequery packets are be sent to the gateway address.
*/
to.sin_addr = packet->raw->giaddr;
if (packet->raw->giaddr.s_addr != htonl(INADDR_LOOPBACK)) {
#if defined(RELAY_PORT)
to.sin_port = relay_port ? relay_port : local_port;
#else
to.sin_port = local_port;
#endif
} else {
to.sin_port = remote_port; /* XXXSK: For debugging. */
}
/*
* The fallback_interface lets us send with a real IP
* address. The packet interface sends from all-zeros.
*/
if (fallback_interface != NULL) {
interface = fallback_interface;
} else {
interface = packet->interface;
}
/*
* Report what we're sending.
*/
log_info("%s to %s for %s (%d associated IPs)",
dhcp_msg_type_name,
inet_ntoa(to.sin_addr), dbg_info, assoc_ip_cnt);
send_packet(interface,
NULL,
packet->raw,
packet->packet_length,
siaddr,
&to,
NULL);
}
#ifdef DHCPv6
/*
* TODO: RFC5007 query-by-clientid.
*
* TODO: RFC5007 look at the pools according to the link-address.
*
* TODO: get fixed leases too.
*
* TODO: RFC5007 ORO in query-options.
*
* TODO: RFC5007 lq-relay-data.
*
* TODO: RFC5007 lq-client-link.
*
* Note: the code is still nearly compliant and usable for the target
* case with these missing features!
*/
/*
* The structure to handle a leasequery.
*/
struct lq6_state {
struct packet *packet;
struct data_string client_id;
struct data_string server_id;
struct data_string lq_query;
uint8_t query_type;
struct in6_addr link_addr;
struct option_state *query_opts;
struct option_state *reply_opts;
unsigned cursor;
union reply_buffer {
unsigned char data[65536];
struct dhcpv6_packet reply;
} buf;
};
/*
* Options that we want to send.
*/
static const int required_opts_lq[] = {
D6O_CLIENTID,
D6O_SERVERID,
D6O_STATUS_CODE,
D6O_CLIENT_DATA,
D6O_LQ_RELAY_DATA,
D6O_LQ_CLIENT_LINK,
0
};
static const int required_opt_CLIENT_DATA[] = {
D6O_CLIENTID,
D6O_IAADDR,
D6O_IAPREFIX,
D6O_CLT_TIME,
0
};
/*
* Get the lq-query option from the packet.
*/
static isc_result_t
get_lq_query(struct lq6_state *lq)
{
struct data_string *lq_query = &lq->lq_query;
struct packet *packet = lq->packet;
struct option_cache *oc;
/*
* Verify our lq_query structure is empty.
*/
if ((lq_query->data != NULL) || (lq_query->len != 0)) {
return DHCP_R_INVALIDARG;
}
oc = lookup_option(&dhcpv6_universe, packet->options, D6O_LQ_QUERY);
if (oc == NULL) {
return ISC_R_NOTFOUND;
}
if (!evaluate_option_cache(lq_query, packet, NULL, NULL,
packet->options, NULL,
&global_scope, oc, MDL)) {
return ISC_R_FAILURE;
}
return ISC_R_SUCCESS;
}
/*
* Message validation, RFC 5007 section 4.2.1:
* dhcpv6.c:valid_client_msg() - unicast + lq-query option.
*/
static int
valid_query_msg(struct lq6_state *lq) {
struct packet *packet = lq->packet;
int ret_val = 0;
struct option_cache *oc;
/* INSIST((lq != NULL) || (packet != NULL)); */
switch (get_client_id(packet, &lq->client_id)) {
case ISC_R_SUCCESS:
break;
case ISC_R_NOTFOUND:
log_debug("Discarding %s from %s; "
"client identifier missing",
dhcpv6_type_names[packet->dhcpv6_msg_type],
piaddr(packet->client_addr));
goto exit;
default:
log_error("Error processing %s from %s; "
"unable to evaluate Client Identifier",
dhcpv6_type_names[packet->dhcpv6_msg_type],
piaddr(packet->client_addr));
goto exit;
}
oc = lookup_option(&dhcpv6_universe, packet->options, D6O_SERVERID);
if (oc != NULL) {
if (evaluate_option_cache(&lq->server_id, packet, NULL, NULL,
packet->options, NULL,
&global_scope, oc, MDL)) {
log_debug("Discarding %s from %s; "
"server identifier found "
"(CLIENTID %s, SERVERID %s)",
dhcpv6_type_names[packet->dhcpv6_msg_type],
piaddr(packet->client_addr),
print_hex_1(lq->client_id.len,
lq->client_id.data, 60),
print_hex_2(lq->server_id.len,
lq->server_id.data, 60));
} else {
log_debug("Discarding %s from %s; "
"server identifier found "
"(CLIENTID %s)",
dhcpv6_type_names[packet->dhcpv6_msg_type],
print_hex_1(lq->client_id.len,
lq->client_id.data, 60),
piaddr(packet->client_addr));
}
goto exit;
}
switch (get_lq_query(lq)) {
case ISC_R_SUCCESS:
break;
case ISC_R_NOTFOUND:
log_debug("Discarding %s from %s; lq-query missing",
dhcpv6_type_names[packet->dhcpv6_msg_type],
piaddr(packet->client_addr));
goto exit;
default:
log_error("Error processing %s from %s; "
"unable to evaluate LQ-Query",
dhcpv6_type_names[packet->dhcpv6_msg_type],
piaddr(packet->client_addr));
goto exit;
}
/* looks good */
ret_val = 1;
exit:
if (!ret_val) {
data_string_forget(&lq->client_id, MDL);
data_string_forget(&lq->server_id, MDL);
data_string_forget(&lq->lq_query, MDL);
}
return ret_val;
}
/*
* Set an error in a status-code option (from set_status_code).
*/
static int
set_error(struct lq6_state *lq, u_int16_t code, const char *message) {
struct data_string d;
int ret_val;
memset(&d, 0, sizeof(d));
d.len = sizeof(code) + strlen(message);
if (!buffer_allocate(&d.buffer, d.len, MDL)) {
log_fatal("set_error: no memory for status code.");
}
d.data = d.buffer->data;
putUShort(d.buffer->data, code);
memcpy(d.buffer->data + sizeof(code), message, d.len - sizeof(code));
if (!save_option_buffer(&dhcpv6_universe, lq->reply_opts,
d.buffer, (unsigned char *)d.data, d.len,
D6O_STATUS_CODE, 0)) {
log_error("set_error: error saving status code.");
ret_val = 0;
} else {
ret_val = 1;
}
data_string_forget(&d, MDL);
return ret_val;
}
/*
* Process a by-address lease query.
*/
static int
process_lq_by_address(struct lq6_state *lq) {
struct packet *packet = lq->packet;
struct option_cache *oc;
struct ipv6_pool *pool = NULL;
struct data_string data;
struct in6_addr addr;
struct iasubopt *iaaddr = NULL;
struct option_state *opt_state = NULL;
u_int32_t lifetime;
unsigned opt_cursor;
int ret_val = 0;
/*
* Get the IAADDR.
*/
oc = lookup_option(&dhcpv6_universe, lq->query_opts, D6O_IAADDR);
if (oc == NULL) {
if (!set_error(lq, STATUS_MalformedQuery,
"No OPTION_IAADDR.")) {
log_error("process_lq_by_address: unable "
"to set MalformedQuery status code.");
return 0;
}
return 1;
}
memset(&data, 0, sizeof(data));
if (!evaluate_option_cache(&data, packet,
NULL, NULL,
lq->query_opts, NULL,
&global_scope, oc, MDL) ||
(data.len < IAADDR_OFFSET)) {
log_error("process_lq_by_address: error evaluating IAADDR.");
goto exit;
}
memcpy(&addr, data.data, sizeof(addr));
data_string_forget(&data, MDL);
/*
* Find the lease.
* Note the RFC 5007 says to use the link-address to find the link
* or the ia-aadr when it is :: but in any case the ia-addr has
* to be on the link, so we ignore the link-address here.
*/
if (find_ipv6_pool(&pool, D6O_IA_NA, &addr) != ISC_R_SUCCESS) {
if (!set_error(lq, STATUS_NotConfigured,
"Address not in a pool.")) {
log_error("process_lq_by_address: unable "
"to set NotConfigured status code.");
goto exit;
}
ret_val = 1;
goto exit;
}
if (iasubopt_hash_lookup(&iaaddr, pool->leases, &addr,
sizeof(addr), MDL) == 0) {
ret_val = 1;
goto exit;
}
if ((iaaddr == NULL) || (iaaddr->state != FTS_ACTIVE) ||
(iaaddr->ia == NULL) || (iaaddr->ia->iaid_duid.len <= 4)) {
ret_val = 1;
goto exit;
}
/*
* Build the client-data option (with client-id, ia-addr and clt-time).
*/
if (!option_state_allocate(&opt_state, MDL)) {
log_error("process_lq_by_address: "
"no memory for option state.");
goto exit;
}
data_string_copy(&data, &iaaddr->ia->iaid_duid, MDL);
data.data += 4;
data.len -= 4;
if (!save_option_buffer(&dhcpv6_universe, opt_state,
NULL, (unsigned char *)data.data, data.len,
D6O_CLIENTID, 0)) {
log_error("process_lq_by_address: error saving client ID.");
goto exit;
}
data_string_forget(&data, MDL);
data.len = IAADDR_OFFSET;
if (!buffer_allocate(&data.buffer, data.len, MDL)) {
log_error("process_lq_by_address: no memory for ia-addr.");
goto exit;
}
data.data = data.buffer->data;
memcpy(data.buffer->data, &iaaddr->addr, 16);
lifetime = iaaddr->prefer;
putULong(data.buffer->data + 16, lifetime);
lifetime = iaaddr->valid;
putULong(data.buffer->data + 20, lifetime);
if (!save_option_buffer(&dhcpv6_universe, opt_state,
NULL, (unsigned char *)data.data, data.len,
D6O_IAADDR, 0)) {
log_error("process_lq_by_address: error saving ia-addr.");
goto exit;
}
data_string_forget(&data, MDL);
lifetime = htonl(iaaddr->ia->cltt);
if (!save_option_buffer(&dhcpv6_universe, opt_state,
NULL, (unsigned char *)&lifetime, 4,
D6O_CLT_TIME, 0)) {
log_error("process_lq_by_address: error saving clt time.");
goto exit;
}
/*
* Store the client-data option.
*/
opt_cursor = lq->cursor;
putUShort(lq->buf.data + lq->cursor, (unsigned)D6O_CLIENT_DATA);
lq->cursor += 2;
/* Skip option length. */
lq->cursor += 2;
lq->cursor += store_options6((char *)lq->buf.data + lq->cursor,
sizeof(lq->buf) - lq->cursor,
opt_state, lq->packet,
required_opt_CLIENT_DATA, NULL);
/* Reset the length. */
putUShort(lq->buf.data + opt_cursor + 2,
lq->cursor - (opt_cursor + 4));
/* Done. */
ret_val = 1;
exit:
if (data.data != NULL)
data_string_forget(&data, MDL);
if (pool != NULL)
ipv6_pool_dereference(&pool, MDL);
if (iaaddr != NULL)
iasubopt_dereference(&iaaddr, MDL);
if (opt_state != NULL)
option_state_dereference(&opt_state, MDL);
return ret_val;
}
/*
* Process a lease query.
*/
void
dhcpv6_leasequery(struct data_string *reply_ret, struct packet *packet) {
static struct lq6_state lq;
struct option_cache *oc;
int allow_lq;
/*
* Initialize the lease query state.
*/
lq.packet = NULL;
memset(&lq.client_id, 0, sizeof(lq.client_id));
memset(&lq.server_id, 0, sizeof(lq.server_id));
memset(&lq.lq_query, 0, sizeof(lq.lq_query));
lq.query_opts = NULL;
lq.reply_opts = NULL;
packet_reference(&lq.packet, packet, MDL);
/*
* Validate our input.
*/
if (!valid_query_msg(&lq)) {
goto exit;
}
/*
* Prepare our reply.
*/
if (!option_state_allocate(&lq.reply_opts, MDL)) {
log_error("dhcpv6_leasequery: no memory for option state.");
goto exit;
}
execute_statements_in_scope(NULL, lq.packet, NULL, NULL,
lq.packet->options, lq.reply_opts,
&global_scope, root_group, NULL, NULL);
lq.buf.reply.msg_type = DHCPV6_LEASEQUERY_REPLY;
memcpy(lq.buf.reply.transaction_id,
lq.packet->dhcpv6_transaction_id,
sizeof(lq.buf.reply.transaction_id));
/*
* Because LEASEQUERY has some privacy concerns, default to deny.
*/
allow_lq = 0;
/*
* See if we are authorized to do LEASEQUERY.
*/
oc = lookup_option(&server_universe, lq.reply_opts, SV_LEASEQUERY);
if (oc != NULL) {
allow_lq = evaluate_boolean_option_cache(NULL,
lq.packet,
NULL, NULL,
lq.packet->options,
lq.reply_opts,
&global_scope,
oc, MDL);
}
if (!allow_lq) {
log_info("dhcpv6_leasequery: not allowed, query ignored.");
goto exit;
}
/*
* Same than transmission of REPLY message in RFC 3315:
* server-id
* client-id
*/
oc = lookup_option(&dhcpv6_universe, lq.reply_opts, D6O_SERVERID);
if (oc == NULL) {
/* If not already in options, get from query then global. */
if (lq.server_id.data == NULL)
copy_server_duid(&lq.server_id, MDL);
if (!save_option_buffer(&dhcpv6_universe,
lq.reply_opts,
NULL,
(unsigned char *)lq.server_id.data,
lq.server_id.len,
D6O_SERVERID,
0)) {
log_error("dhcpv6_leasequery: "
"error saving server identifier.");
goto exit;
}
}
if (!save_option_buffer(&dhcpv6_universe,
lq.reply_opts,
lq.client_id.buffer,
(unsigned char *)lq.client_id.data,
lq.client_id.len,
D6O_CLIENTID,
0)) {
log_error("dhcpv6_leasequery: "
"error saving client identifier.");
goto exit;
}
lq.cursor = 4;
/*
* Decode the lq-query option.
*/
if (lq.lq_query.len <= LQ_QUERY_OFFSET) {
if (!set_error(&lq, STATUS_MalformedQuery,
"OPTION_LQ_QUERY too short.")) {
log_error("dhcpv6_leasequery: unable "
"to set MalformedQuery status code.");
goto exit;
}
goto done;
}
lq.query_type = lq.lq_query.data [0];
memcpy(&lq.link_addr, lq.lq_query.data + 1, sizeof(lq.link_addr));
switch (lq.query_type) {
case LQ6QT_BY_ADDRESS:
break;
case LQ6QT_BY_CLIENTID:
if (!set_error(&lq, STATUS_UnknownQueryType,
"QUERY_BY_CLIENTID not supported.")) {
log_error("dhcpv6_leasequery: unable to "
"set UnknownQueryType status code.");
goto exit;
}
goto done;
default:
if (!set_error(&lq, STATUS_UnknownQueryType,
"Unknown query-type.")) {
log_error("dhcpv6_leasequery: unable to "
"set UnknownQueryType status code.");
goto exit;
}
goto done;
}
if (!option_state_allocate(&lq.query_opts, MDL)) {
log_error("dhcpv6_leasequery: no memory for option state.");
goto exit;
}
if (!parse_option_buffer(lq.query_opts,
lq.lq_query.data + LQ_QUERY_OFFSET,
lq.lq_query.len - LQ_QUERY_OFFSET,
&dhcpv6_universe)) {
log_error("dhcpv6_leasequery: error parsing query-options.");
if (!set_error(&lq, STATUS_MalformedQuery,
"Bad query-options.")) {
log_error("dhcpv6_leasequery: unable "
"to set MalformedQuery status code.");
goto exit;
}
goto done;
}
/* Do it. */
if (!process_lq_by_address(&lq))
goto exit;
done:
/* Store the options. */
lq.cursor += store_options6((char *)lq.buf.data + lq.cursor,
sizeof(lq.buf) - lq.cursor,
lq.reply_opts,
lq.packet,
required_opts_lq,
NULL);
/* Return our reply to the caller. */
reply_ret->len = lq.cursor;
reply_ret->buffer = NULL;
if (!buffer_allocate(&reply_ret->buffer, lq.cursor, MDL)) {
log_fatal("dhcpv6_leasequery: no memory to store Reply.");
}
memcpy(reply_ret->buffer->data, lq.buf.data, lq.cursor);
reply_ret->data = reply_ret->buffer->data;
exit:
/* Cleanup. */
if (lq.packet != NULL)
packet_dereference(&lq.packet, MDL);
if (lq.client_id.data != NULL)
data_string_forget(&lq.client_id, MDL);
if (lq.server_id.data != NULL)
data_string_forget(&lq.server_id, MDL);
if (lq.lq_query.data != NULL)
data_string_forget(&lq.lq_query, MDL);
if (lq.query_opts != NULL)
option_state_dereference(&lq.query_opts, MDL);
if (lq.reply_opts != NULL)
option_state_dereference(&lq.reply_opts, MDL);
}
#endif /* DHCPv6 */
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