--- /dev/null
+/* ddns.c
+
+ Dynamic DNS updates. */
+
+/*
+ * 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 The Internet Software Consortium nor the names
+ * of its contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
+ * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * This software has been written for the Internet Software Consortium
+ * by Ted Lemon in cooperation with Vixie Enterprises and Nominum, Inc.
+ * To learn more about the Internet Software Consortium, see
+ * ``http://www.isc.org/''. To learn more about Vixie Enterprises,
+ * see ``http://www.vix.com''. To learn more about Nominum, Inc., see
+ * ``http://www.nominum.com''.
+ */
+
+#ifndef lint
+static char copyright[] =
+"$Id: ddns.c,v 1.1 2000/12/11 18:56:41 neild Exp $ Copyright (c) 1995-2000 The Internet Software Consortium. All rights reserved.\n";
+#endif /* not lint */
+
+#include "dhcpd.h"
+#include "../minires/md5.h"
+
+#ifdef NSUPDATE
+
+/* Have to use TXT records for now. */
+#define T_DHCID T_TXT
+
+static int get_dhcid (unsigned char *, struct lease *);
+
+static struct __res_state resolver_state;
+static int resolver_inited = 0;
+
+
+static int get_dhcid (unsigned char *dhcid, struct lease *lease) {
+ unsigned char buf[MD5_DIGEST_LENGTH];
+ MD5_CTX md5;
+ int i;
+
+ /*
+ * DHCP clients and servers should use the following forms of client
+ * identification, starting with the most preferable, and finishing
+ * with the least preferable. If the client does not send any of these
+ * forms of identification, the DHCP/DDNS interaction is not defined by
+ * this specification. The most preferable form of identification is
+ * the Globally Unique Identifier Option [TBD]. Next is the DHCP
+ * Client Identifier option. Last is the client's link-layer address,
+ * as conveyed in its DHCPREQUEST message. Implementors should note
+ * that the link-layer address cannot be used if there are no
+ * significant bytes in the chaddr field of the DHCP client's request,
+ * because this does not constitute a unique identifier.
+ * -- "Interaction between DHCP and DNS"
+ * <draft-ietf-dhc-dhcp-dns-12.txt>
+ * M. Stapp, Y. Rekhter
+ */
+
+ MD5_Init (&md5);
+
+ if (lease -> uid) {
+ /* Use the DHCP Client Identifier option. */
+ MD5_Update (&md5, lease -> uid, lease -> uid_len);
+ } else if (lease -> hardware_addr . hlen) {
+ /* Use the link-layer address. */
+ MD5_Update (&md5,
+ lease -> hardware_addr.hbuf,
+ lease -> hardware_addr.hlen);
+ } else {
+ /* Uh-oh. Something isn't right here. */
+ return 1;
+ }
+
+ MD5_Final (buf, &md5);
+
+ /* Convert into ASCII. */
+ for (i = 0; i < MD5_DIGEST_LENGTH; i++) {
+ dhcid [i*2] = "0123456789abcdef"[(buf[i]>>4)&0xf];
+ dhcid [i*2+1] = "0123456789abcdef"[ buf[i] &0xf];
+ }
+ dhcid [MD5_DIGEST_LENGTH*2] = '\0';
+
+ return 0;
+}
+
+
+/* NB: No way of checking that there is enough space in a data_string's
+ buffer. Be certain to allocate enough! */
+static void data_string_append (struct data_string *ds1,
+ struct data_string *ds2)
+{
+ memcpy (ds1 -> buffer -> data + ds1 -> len,
+ ds2 -> data,
+ ds2 -> len);
+ ds1 -> len += ds2 -> len;
+}
+
+
+static struct binding *create_binding (struct binding_scope **scope,
+ const char *name)
+{
+ struct binding *binding;
+
+ if (!*scope) {
+ if (!binding_scope_allocate (scope, MDL))
+ return (struct binding *)0;
+ }
+
+ binding = find_binding (*scope, name);
+ if (!binding) {
+ binding = dmalloc (sizeof *binding, MDL);
+ if (!binding)
+ return (struct binding *)0;
+
+ memset (binding, 0, sizeof *binding);
+ binding -> name = dmalloc (strlen (name) + 1, MDL);
+ if (!binding -> name) {
+ dfree (binding, MDL);
+ return (struct binding *)0;
+ }
+ strcpy (binding -> name, name);
+
+ binding -> next = (*scope) -> bindings;
+ (*scope) -> bindings = binding;
+ }
+
+ return binding;
+}
+
+
+static int bind_ds_value (struct binding_scope **scope,
+ const char *name,
+ struct data_string *value)
+{
+ struct binding *binding;
+
+ binding = create_binding (scope, name);
+ if (!binding)
+ return 0;
+
+ if (binding -> value)
+ binding_value_dereference (&binding -> value, MDL);
+
+ if (!binding_value_allocate (&binding -> value, MDL))
+ return 0;
+
+ data_string_copy (&binding -> value -> value.data, value, MDL);
+ binding -> value -> type = binding_data;
+
+ return 1;
+}
+
+
+static int find_bound_string (struct data_string *value,
+ struct binding_scope *scope,
+ const char *name)
+{
+ struct binding *binding;
+
+ binding = find_binding (scope, name);
+ if (!binding ||
+ !binding -> value ||
+ binding -> value -> type != binding_data)
+ return 0;
+
+ if (binding -> value -> value.data.terminated) {
+ data_string_copy (value, &binding -> value -> value.data, MDL);
+ } else {
+ buffer_allocate (&value -> buffer,
+ binding -> value -> value.data.len,
+ MDL);
+ if (!value -> buffer)
+ return 0;
+
+ memcpy (value -> buffer -> data,
+ binding -> value -> value.data.data,
+ binding -> value -> value.data.len);
+ value -> data = value -> buffer -> data;
+ value -> len = binding -> value -> value.data.len;
+
+ data_string_forget (&binding -> value -> value.data, MDL);
+ data_string_copy (&binding -> value -> value.data, value, MDL);
+ }
+
+ return 1;
+}
+
+
+static ns_rcode ddns_update_a (struct data_string *ddns_fwd_name,
+ struct data_string *ddns_address,
+ struct data_string *ddns_dhcid,
+ unsigned long ttl)
+{
+ ns_updque updque;
+ ns_updrec *updrec;
+ ns_rcode result;
+
+ /*
+ * When a DHCP client or server intends to update an A RR, it first
+ * prepares a DNS UPDATE query which includes as a prerequisite the
+ * assertion that the name does not exist. The update section of the
+ * query attempts to add the new name and its IP address mapping (an A
+ * RR), and the DHCID RR with its unique client-identity.
+ * -- "Interaction between DHCP and DNS"
+ */
+
+ ISC_LIST_INIT (updque);
+
+ /*
+ * A RR does not exist.
+ */
+ updrec = minires_mkupdrec (S_PREREQ, ddns_fwd_name -> data,
+ C_IN, T_A, 0);
+ if (!updrec) goto error;
+
+ updrec -> r_data = (unsigned char *)0;
+ updrec -> r_size = 0;
+ updrec -> r_opcode = NXDOMAIN;
+
+ ISC_LIST_APPEND (updque, updrec, r_link);
+
+
+ /*
+ * Add A RR.
+ */
+ updrec = minires_mkupdrec (S_UPDATE, ddns_fwd_name -> data,
+ C_IN, T_A, ttl);
+ if (!updrec) goto error;
+
+ updrec -> r_data = ddns_address -> buffer -> data;
+ updrec -> r_size = ddns_address -> len;
+ updrec -> r_opcode = ADD;
+
+ ISC_LIST_APPEND (updque, updrec, r_link);
+
+
+ /*
+ * Add DHCID RR.
+ */
+ updrec = minires_mkupdrec (S_UPDATE, ddns_fwd_name -> data,
+ C_IN, T_DHCID, ttl);
+ if (!updrec) goto error;
+
+ updrec -> r_data = ddns_dhcid -> buffer -> data;
+ updrec -> r_size = ddns_dhcid -> len;
+ updrec -> r_opcode = ADD;
+
+ ISC_LIST_APPEND (updque, updrec, r_link);
+
+
+ /*
+ * Attempt to perform the update.
+ */
+ result = minires_nupdate (&resolver_state, ISC_LIST_HEAD (updque));
+
+ while (!ISC_LIST_EMPTY (updque)) {
+ updrec = ISC_LIST_HEAD (updque);
+ ISC_LIST_UNLINK (updque, updrec, r_link);
+ minires_freeupdrec (updrec);
+ }
+
+
+ /*
+ * If this update operation succeeds, the updater can conclude that it
+ * has added a new name whose only RRs are the A and DHCID RR records.
+ * The A RR update is now complete (and a client updater is finished,
+ * while a server might proceed to perform a PTR RR update).
+ * -- "Interaction between DHCP and DNS"
+ */
+
+ if (result == NOERROR)
+ return result;
+
+
+ /*
+ * If the first update operation fails with YXDOMAIN, the updater can
+ * conclude that the intended name is in use. The updater then
+ * attempts to confirm that the DNS name is not being used by some
+ * other host. The updater prepares a second UPDATE query in which the
+ * prerequisite is that the desired name has attached to it a DHCID RR
+ * whose contents match the client identity. The update section of
+ * this query deletes the existing A records on the name, and adds the
+ * A record that matches the DHCP binding and the DHCID RR with the
+ * client identity.
+ * -- "Interaction between DHCP and DNS"
+ */
+
+ if (result != YXDOMAIN)
+ return result;
+
+
+ /*
+ * DHCID RR exists, and matches client identity.
+ */
+ updrec = minires_mkupdrec (S_PREREQ, ddns_fwd_name -> data,
+ C_IN, T_DHCID, 0);
+ if (!updrec) goto error;
+
+ updrec -> r_data = ddns_dhcid -> buffer -> data;
+ updrec -> r_size = ddns_dhcid -> len;
+ updrec -> r_opcode = YXRRSET;
+
+ ISC_LIST_APPEND (updque, updrec, r_link);
+
+
+ /*
+ * Delete A RRset.
+ */
+ updrec = minires_mkupdrec (S_UPDATE, ddns_fwd_name -> data,
+ C_IN, T_A, 0);
+ if (!updrec) goto error;
+
+ updrec -> r_data = (unsigned char *)0;
+ updrec -> r_size = 0;
+ updrec -> r_opcode = DELETE;
+
+ ISC_LIST_APPEND (updque, updrec, r_link);
+
+
+ /*
+ * Add A RR.
+ */
+ updrec = minires_mkupdrec (S_UPDATE, ddns_fwd_name -> data,
+ C_IN, T_A, ttl);
+ if (!updrec) goto error;
+
+ updrec -> r_data = ddns_address -> buffer -> data;
+ updrec -> r_size = ddns_address -> len;
+ updrec -> r_opcode = ADD;
+
+ ISC_LIST_APPEND (updque, updrec, r_link);
+
+
+ /*
+ * Attempt to perform the update.
+ */
+ result = minires_nupdate (&resolver_state, ISC_LIST_HEAD (updque));
+
+ while (!ISC_LIST_EMPTY (updque)) {
+ updrec = ISC_LIST_HEAD (updque);
+ ISC_LIST_UNLINK (updque, updrec, r_link);
+ minires_freeupdrec (updrec);
+ }
+
+
+ /*
+ * If this query succeeds, the updater can conclude that the current
+ * client was the last client associated with the domain name, and that
+ * the name now contains the updated A RR. The A RR update is now
+ * complete (and a client updater is finished, while a server would
+ * then proceed to perform a PTR RR update).
+ * -- "Interaction between DHCP and DNS"
+ */
+
+ if (result == NOERROR)
+ return result;
+
+
+ /*
+ * If the second query fails with NXRRSET, the updater must conclude
+ * that the client's desired name is in use by another host. At this
+ * juncture, the updater can decide (based on some administrative
+ * configuration outside of the scope of this document) whether to let
+ * the existing owner of the name keep that name, and to (possibly)
+ * perform some name disambiguation operation on behalf of the current
+ * client, or to replace the RRs on the name with RRs that represent
+ * the current client. If the configured policy allows replacement of
+ * existing records, the updater submits a query that deletes the
+ * existing A RR and the existing DHCID RR, adding A and DHCID RRs that
+ * represent the IP address and client-identity of the new client.
+ * -- "Interaction between DHCP and DNS"
+ */
+
+ return result;
+
+
+ error:
+ while (!ISC_LIST_EMPTY (updque)) {
+ updrec = ISC_LIST_HEAD (updque);
+ ISC_LIST_UNLINK (updque, updrec, r_link);
+ minires_freeupdrec (updrec);
+ }
+
+ return SERVFAIL;
+}
+
+
+static ns_rcode ddns_update_ptr (struct data_string *ddns_fwd_name,
+ struct data_string *ddns_rev_name,
+ struct data_string *ddns_dhcid,
+ unsigned long ttl)
+{
+ ns_updque updque;
+ ns_updrec *updrec;
+ ns_rcode result = SERVFAIL;
+
+ /*
+ * The DHCP server submits a DNS query which deletes all of the PTR RRs
+ * associated with the lease IP address, and adds a PTR RR whose data
+ * is the client's (possibly disambiguated) host name. The server also
+ * adds a DHCID RR specified in Section 4.3.
+ * -- "Interaction between DHCP and DNS"
+ */
+
+ ISC_LIST_INIT (updque);
+
+ /*
+ * Delete all PTR RRs.
+ */
+ updrec = minires_mkupdrec (S_UPDATE, ddns_rev_name -> data,
+ C_IN, T_PTR, 0);
+ if (!updrec) goto error;
+
+ updrec -> r_data = (unsigned char *)0;
+ updrec -> r_size = 0;
+ updrec -> r_opcode = DELETE;
+
+ ISC_LIST_APPEND (updque, updrec, r_link);
+
+
+ /*
+ * Add PTR RR.
+ */
+ updrec = minires_mkupdrec (S_UPDATE, ddns_rev_name -> data,
+ C_IN, T_PTR, ttl);
+ if (!updrec) goto error;
+
+ updrec -> r_data = ddns_fwd_name -> buffer -> data;
+ updrec -> r_size = ddns_fwd_name -> len;
+ updrec -> r_opcode = ADD;
+
+ ISC_LIST_APPEND (updque, updrec, r_link);
+
+
+ /*
+ * Add DHCID RR.
+ */
+ updrec = minires_mkupdrec (S_UPDATE, ddns_rev_name -> data,
+ C_IN, T_DHCID,ttl);
+ if (!updrec) goto error;
+
+ updrec -> r_data = ddns_dhcid -> buffer -> data;
+ updrec -> r_size = ddns_dhcid -> len;
+ updrec -> r_opcode = ADD;
+
+ ISC_LIST_APPEND (updque, updrec, r_link);
+
+
+ /*
+ * Attempt to perform the update.
+ */
+ result = minires_nupdate (&resolver_state, ISC_LIST_HEAD (updque));
+
+
+ /* Fall through. */
+ error:
+
+ while (!ISC_LIST_EMPTY (updque)) {
+ updrec = ISC_LIST_HEAD (updque);
+ ISC_LIST_UNLINK (updque, updrec, r_link);
+ minires_freeupdrec (updrec);
+ }
+
+ return result;
+}
+
+
+static ns_rcode ddns_remove_a (struct data_string *ddns_fwd_name,
+ struct data_string *ddns_address,
+ struct data_string *ddns_dhcid)
+{
+ ns_updque updque;
+ ns_updrec *updrec;
+ ns_rcode result = SERVFAIL;
+
+ /*
+ * The entity chosen to handle the A record for this client (either the
+ * client or the server) SHOULD delete the A record that was added when
+ * the lease was made to the client.
+ *
+ * In order to perform this delete, the updater prepares an UPDATE
+ * query which contains two prerequisites. The first prerequisite
+ * asserts that the DHCID RR exists whose data is the client identity
+ * described in Section 4.3. The second prerequisite asserts that the
+ * data in the A RR contains the IP address of the lease that has
+ * expired or been released.
+ * -- "Interaction between DHCP and DNS"
+ */
+
+ ISC_LIST_INIT (updque);
+
+ /*
+ * DHCID RR exists, and matches client identity.
+ */
+ updrec = minires_mkupdrec (S_PREREQ, ddns_fwd_name -> data,
+ C_IN, T_DHCID,0);
+ if (!updrec) goto error;
+
+ updrec -> r_data = ddns_dhcid -> buffer -> data;
+ updrec -> r_size = ddns_dhcid -> len;
+ updrec -> r_opcode = YXRRSET;
+
+ ISC_LIST_APPEND (updque, updrec, r_link);
+
+
+ /*
+ * A RR matches the expiring lease.
+ */
+ updrec = minires_mkupdrec (S_PREREQ, ddns_fwd_name -> data,
+ C_IN, T_A, 0);
+ if (!updrec) goto error;
+
+ updrec -> r_data = ddns_address -> buffer -> data;
+ updrec -> r_size = ddns_address -> len;
+ updrec -> r_opcode = YXRRSET;
+
+ ISC_LIST_APPEND (updque, updrec, r_link);
+
+
+ /*
+ * Delete appropriate A RR.
+ */
+ updrec = minires_mkupdrec (S_UPDATE, ddns_fwd_name -> data,
+ C_IN, T_A, 0);
+ if (!updrec) goto error;
+
+ updrec -> r_data = ddns_address -> buffer -> data;
+ updrec -> r_size = ddns_address -> len;
+ updrec -> r_opcode = DELETE;
+
+ ISC_LIST_APPEND (updque, updrec, r_link);
+
+
+ /*
+ * Delete appropriate DHCID RR.
+ */
+ updrec = minires_mkupdrec (S_UPDATE, ddns_fwd_name -> data,
+ C_IN, T_DHCID, 0);
+ if (!updrec) goto error;
+
+ updrec -> r_data = ddns_dhcid -> buffer -> data;
+ updrec -> r_size = ddns_dhcid -> len;
+ updrec -> r_opcode = DELETE;
+
+ ISC_LIST_APPEND (updque, updrec, r_link);
+
+
+ /*
+ * Attempt to perform the update.
+ */
+ result = minires_nupdate (&resolver_state, ISC_LIST_HEAD (updque));
+
+
+ /*
+ * If the query fails, the updater MUST NOT delete the DNS name. It
+ * may be that the host whose lease on the server has expired has moved
+ * to another network and obtained a lease from a different server,
+ * which has caused the client's A RR to be replaced. It may also be
+ * that some other client has been configured with a name that matches
+ * the name of the DHCP client, and the policy was that the last client
+ * to specify the name would get the name. In this case, the DHCID RR
+ * will no longer match the updater's notion of the client-identity of
+ * the host pointed to by the DNS name.
+ * -- "Interaction between DHCP and DNS"
+ */
+
+
+ /* Fall through. */
+ error:
+
+ while (!ISC_LIST_EMPTY (updque)) {
+ updrec = ISC_LIST_HEAD (updque);
+ ISC_LIST_UNLINK (updque, updrec, r_link);
+ minires_freeupdrec (updrec);
+ }
+
+ return result;
+}
+
+
+static ns_rcode ddns_remove_ptr (struct data_string *ddns_fwd_name,
+ struct data_string *ddns_rev_name,
+ struct data_string *ddns_dhcid)
+{
+ ns_updque updque;
+ ns_updrec *updrec;
+ ns_rcode result = SERVFAIL;
+
+ /*
+ * When a lease expires or a DHCP client issues a DHCPRELEASE request,
+ * the DHCP server SHOULD delete the PTR RR that matches the DHCP
+ * binding, if one was successfully added. The server's update query
+ * SHOULD assert that the name in the PTR record matches the name of
+ * the client whose lease has expired or been released.
+ * -- "Interaction between DHCP and DNS"
+ */
+
+ ISC_LIST_INIT (updque);
+
+ /*
+ * Delete appropriate PTR RR.
+ */
+ updrec = minires_mkupdrec (S_UPDATE, ddns_rev_name -> data,
+ C_IN, T_PTR, 0);
+ if (!updrec) goto error;
+
+ updrec -> r_data = ddns_fwd_name -> buffer -> data;
+ updrec -> r_size = ddns_fwd_name -> len;
+ updrec -> r_opcode = DELETE;
+
+ ISC_LIST_APPEND (updque, updrec, r_link);
+
+
+ /*
+ * Delete appropriate DHCID RR.
+ */
+ updrec = minires_mkupdrec (S_UPDATE, ddns_rev_name -> data,
+ C_IN, T_DHCID, 0);
+ if (!updrec) goto error;
+
+ updrec -> r_data = ddns_dhcid -> buffer -> data;
+ updrec -> r_size = ddns_dhcid -> len;
+ updrec -> r_opcode = DELETE;
+
+ ISC_LIST_APPEND (updque, updrec, r_link);
+
+
+ /*
+ * Attempt to perform the update.
+ */
+ result = minires_nupdate (&resolver_state, ISC_LIST_HEAD (updque));
+
+
+ /* Fall through. */
+ error:
+
+ while (!ISC_LIST_EMPTY (updque)) {
+ updrec = ISC_LIST_HEAD (updque);
+ ISC_LIST_UNLINK (updque, updrec, r_link);
+ minires_freeupdrec (updrec);
+ }
+
+ return result;
+}
+
+
+int ddns_updates (struct packet *packet,
+ struct lease *lease,
+ struct lease_state *state)
+{
+ unsigned long ddns_ttl = DEFAULT_DDNS_TTL;
+ struct data_string ddns_hostname;
+ struct data_string ddns_domainname;
+ struct data_string ddns_fwd_name;
+ struct data_string ddns_rev_name;
+ struct data_string ddns_address;
+ struct data_string ddns_dhcid;
+ unsigned len;
+ unsigned ddns_address_len = 0;
+ struct data_string d1;
+ struct option_cache *oc;
+ int s1, s2;
+ int result = 0;
+ ns_rcode rcode1, rcode2;
+
+ /* Can only cope with IPv4 addrs at the moment. */
+ if (lease -> ip_addr . len != 4)
+ return 0;
+
+
+ memset (&ddns_hostname, 0, sizeof (ddns_hostname));
+ memset (&ddns_domainname, 0, sizeof (ddns_domainname));
+ memset (&ddns_fwd_name, 0, sizeof (ddns_fwd_name));
+ memset (&ddns_rev_name, 0, sizeof (ddns_rev_name));
+ memset (&ddns_address, 0, sizeof (ddns_address));
+ memset (&ddns_dhcid, 0, sizeof (ddns_dhcid));
+
+
+ /*
+ * Look up the RR TTL.
+ */
+ ddns_ttl = DEFAULT_DDNS_TTL;
+ if ((oc = lookup_option (&server_universe, state -> options,
+ SV_DDNS_TTL))) {
+ if (evaluate_option_cache (&d1, packet, lease,
+ (struct client_state *)0,
+ packet -> options,
+ state -> options,
+ &lease -> scope, oc, MDL)) {
+ if (d1.len == sizeof (u_int32_t))
+ ddns_ttl = getULong (d1.data);
+ data_string_forget (&d1, MDL);
+ }
+ }
+
+
+ /*
+ * Look up the lease FQDN.
+ */
+ s1 = s2 = 0;
+
+ oc = lookup_option (&server_universe, state -> options,
+ SV_DDNS_HOST_NAME);
+ if (oc)
+ s1 = evaluate_option_cache (&ddns_hostname, packet, lease,
+ (struct client_state *)0,
+ packet -> options,
+ state -> options,
+ &lease -> scope, oc, MDL);
+
+ oc = lookup_option (&server_universe, state -> options,
+ SV_DDNS_DOMAIN_NAME);
+ if (oc)
+ s2 = evaluate_option_cache (&ddns_domainname, packet, lease,
+ (struct client_state *)0,
+ packet -> options,
+ state -> options,
+ &lease -> scope, oc, MDL);
+
+ if (s1 && s2) {
+ buffer_allocate (&ddns_fwd_name.buffer,
+ ddns_hostname.len + ddns_domainname.len + 2,
+ MDL);
+ if (ddns_fwd_name.buffer) {
+ ddns_fwd_name.data = ddns_fwd_name.buffer -> data;
+ data_string_append (&ddns_fwd_name, &ddns_hostname);
+ ddns_fwd_name.buffer -> data [ddns_fwd_name.len] = '.';
+ ddns_fwd_name.len++;
+ data_string_append (&ddns_fwd_name, &ddns_domainname);
+ ddns_fwd_name.buffer -> data [ddns_fwd_name.len] ='\0';
+ ddns_fwd_name.terminated = 1;
+ }
+ }
+
+
+ /*
+ * Look up the lease IP address (as a string).
+ */
+ /* XXX.XXX.XXX.XXX\0 = 16 characters. */
+ buffer_allocate (&ddns_address.buffer, 16, MDL);
+
+#ifndef NO_SNPRINTF
+ snprintf (ddns_address.buffer -> data, 16,
+ "%d.%d.%d.%d",
+ lease -> ip_addr . iabuf[0],
+ lease -> ip_addr . iabuf[1],
+ lease -> ip_addr . iabuf[2],
+ lease -> ip_addr . iabuf[3]);
+#else
+ sprintf (ddns_address.buffer -> data,
+ "%d.%d.%d.%d",
+ lease -> ip_addr . iabuf[0],
+ lease -> ip_addr . iabuf[1],
+ lease -> ip_addr . iabuf[2],
+ lease -> ip_addr . iabuf[3]);
+#endif
+ ddns_address.data = ddns_address.buffer -> data;
+ ddns_address.len = strlen (ddns_address.data);
+ ddns_address.terminated = 1;
+
+
+ /*
+ * Look up the reverse IP name.
+ */
+ oc = lookup_option (&server_universe, state -> options,
+ SV_DDNS_REV_DOMAIN_NAME);
+ if (oc)
+ s1 = evaluate_option_cache (&d1, packet, lease,
+ (struct client_state *)0,
+ packet -> options,
+ state -> options,
+ &lease -> scope, oc, MDL);
+
+ if (oc && s1) {
+ /* Buffer length:
+ XXX.XXX.XXX.XXX.<ddns-rev-domain-name>\0 */
+ buffer_allocate (&ddns_rev_name.buffer,
+ d1.len + 17, MDL);
+ if (ddns_rev_name.buffer) {
+ ddns_rev_name.data = ddns_rev_name.buffer -> data;
+#ifndef NO_SNPRINTF
+ snprintf (ddns_rev_name.buffer -> data, 17,
+ "%d.%d.%d.%d.",
+ lease -> ip_addr . iabuf[3],
+ lease -> ip_addr . iabuf[2],
+ lease -> ip_addr . iabuf[1],
+ lease -> ip_addr . iabuf[0]);
+#else
+ sprintf (ddns_rev_name.buffer -> data,
+ "%d.%d.%d.%d.",
+ lease -> ip_addr . iabuf[3],
+ lease -> ip_addr . iabuf[2],
+ lease -> ip_addr . iabuf[1],
+ lease -> ip_addr . iabuf[0]);
+#endif
+ ddns_rev_name.len = strlen (ddns_rev_name.data);
+ data_string_append (&ddns_rev_name, &d1);
+ ddns_rev_name.buffer -> data [ddns_rev_name.len] ='\0';
+ ddns_rev_name.terminated = 1;
+ }
+
+ data_string_forget (&d1, MDL);
+ }
+
+
+ /*
+ * Look up the DHCID value. (Should this be cached in the lease?)
+ */
+ buffer_allocate (&ddns_dhcid.buffer, (MD5_DIGEST_LENGTH*2)+1, MDL);
+ if (ddns_dhcid.buffer) {
+ get_dhcid (ddns_dhcid.buffer -> data, lease);
+ ddns_dhcid.data = ddns_dhcid.buffer -> data;
+ ddns_dhcid.len = MD5_DIGEST_LENGTH * 2;
+ ddns_dhcid.terminated = 1;
+ }
+
+
+ /*
+ * Start the resolver, if necessary.
+ */
+ if (!resolver_inited) {
+ minires_ninit (&resolver_state);
+ resolver_inited = 1;
+ }
+
+
+ /*
+ * Perform updates.
+ */
+ if (ddns_fwd_name.len && ddns_address.len && ddns_dhcid.len)
+ rcode1 = ddns_update_a(&ddns_fwd_name, &ddns_address,
+ &ddns_dhcid, ddns_ttl);
+
+ if (ddns_fwd_name.len && ddns_rev_name.len && ddns_dhcid.len)
+ rcode2 = ddns_update_ptr(&ddns_fwd_name, &ddns_rev_name,
+ &ddns_dhcid, ddns_ttl);
+
+ /* minires_update() can return -1 under certain circumstances. */
+ if (rcode1 == -1)
+ rcode1 = SERVFAIL;
+ if (rcode2 == -1)
+ rcode2 = SERVFAIL;
+
+ if (rcode1 == NOERROR || rcode2 == NOERROR) {
+ bind_ds_value (&lease -> scope, "ddns-fwd-name",
+ &ddns_fwd_name);
+ bind_ds_value (&lease -> scope, "ddns-dhcid",
+ &ddns_dhcid);
+ }
+ if (rcode1 == NOERROR) {
+ bind_ds_value (&lease -> scope, "ddns-address",
+ &ddns_address);
+ }
+ if (rcode2 == NOERROR) {
+ bind_ds_value (&lease -> scope, "ddns-rev-name",
+ &ddns_rev_name);
+ }
+
+
+ /*
+ * If the client sent us the FQDN option, respond appropriately.
+ */
+ oc = lookup_option (&fqdn_universe, packet -> options,
+ FQDN_SERVER_UPDATE);
+ if (oc) {
+ oc -> data.buffer -> data[0] = 1;
+ }
+
+ oc = lookup_option (&fqdn_universe, packet -> options,
+ FQDN_NO_CLIENT_UPDATE);
+ if (oc) {
+ oc -> data.buffer -> data[0] = 1;
+ }
+
+ oc = lookup_option (&fqdn_universe, packet -> options,
+ FQDN_RCODE1);
+ if (oc) {
+ oc -> data.buffer -> data[0] = rcode1;
+ }
+
+ oc = lookup_option (&fqdn_universe, packet -> options,
+ FQDN_RCODE2);
+ if (oc) {
+ oc -> data.buffer -> data[0] = rcode2;
+ }
+
+ oc = lookup_option (&fqdn_universe, packet -> options,
+ FQDN_HOSTNAME);
+ if (oc && ddns_hostname.buffer) {
+ data_string_forget (&oc -> data, MDL);
+ data_string_copy (&oc -> data, &ddns_hostname, MDL);
+ }
+
+ oc = lookup_option (&fqdn_universe, packet -> options,
+ FQDN_DOMAINNAME);
+ if (oc && ddns_hostname.buffer) {
+ data_string_forget (&oc -> data, MDL);
+ data_string_copy (&oc -> data, &ddns_domainname, MDL);
+ }
+
+
+ /*
+ * Final cleanup.
+ */
+ data_string_forget (&ddns_hostname, MDL);
+ data_string_forget (&ddns_domainname, MDL);
+ data_string_forget (&ddns_fwd_name, MDL);
+ data_string_forget (&ddns_rev_name, MDL);
+ data_string_forget (&ddns_address, MDL);
+ data_string_forget (&ddns_dhcid, MDL);
+
+ return rcode1 == NOERROR || rcode2 == NOERROR;
+}
+
+
+int ddns_removals(struct lease *lease) {
+ struct data_string ddns_fwd_name;
+ struct data_string ddns_rev_name;
+ struct data_string ddns_address;
+ struct data_string ddns_dhcid;
+ ns_rcode rcode;
+
+ /* No scope implies that DDNS has not been performed for this lease. */
+ if (!lease -> scope)
+ return 1;
+
+
+ /*
+ * Look up stored names.
+ */
+ memset (&ddns_fwd_name, 0, sizeof (ddns_fwd_name));
+ memset (&ddns_rev_name, 0, sizeof (ddns_rev_name));
+ memset (&ddns_address, 0, sizeof (ddns_address));
+ memset (&ddns_dhcid, 0, sizeof (ddns_dhcid));
+
+ find_bound_string (&ddns_fwd_name, lease -> scope, "ddns-fwd-name");
+ find_bound_string (&ddns_rev_name, lease -> scope, "ddns-rev-name");
+ find_bound_string (&ddns_address, lease -> scope, "ddns-address");
+ find_bound_string (&ddns_dhcid, lease -> scope, "ddns-dhcid");
+
+
+ /*
+ * Start the resolver, if necessary.
+ */
+ if (!resolver_inited) {
+ minires_ninit (&resolver_state);
+ resolver_inited = 1;
+ }
+
+
+ /*
+ * Perform removals.
+ */
+ if (ddns_fwd_name.len && ddns_address.len && ddns_dhcid.len) {
+ rcode = ddns_remove_a (&ddns_fwd_name, &ddns_address,
+ &ddns_dhcid);
+ }
+ if (ddns_fwd_name.len && ddns_rev_name.len && ddns_dhcid.len) {
+ rcode = ddns_remove_ptr(&ddns_fwd_name, &ddns_rev_name,
+ &ddns_dhcid);
+ }
+
+
+ data_string_forget (&ddns_fwd_name, MDL);
+ data_string_forget (&ddns_rev_name, MDL);
+ data_string_forget (&ddns_address, MDL);
+ data_string_forget (&ddns_dhcid, MDL);
+
+
+ return 1;
+}
+
+
+#endif /* NSUPDATE */
projects / thirdparty / dhcp.git / commitdiff
