int ddns_updates (struct packet *packet,
struct lease *lease, struct lease *old,
struct lease_state *state)
{
unsigned long ddns_ttl = DEFAULT_DDNS_TTL;
struct data_string ddns_hostname;
struct data_string ddns_domainname;
struct data_string old_ddns_fwd_name;
struct data_string ddns_fwd_name;
struct data_string ddns_rev_name;
struct data_string ddns_dhcid;
unsigned len;
struct data_string d1;
struct option_cache *oc;
int s1, s2;
int result = 0;
isc_result_t rcode1 = ISC_R_SUCCESS, rcode2 = ISC_R_SUCCESS;
int server_updates_a = 1;
int server_updates_ptr = 1;
struct buffer *bp = (struct buffer *)0;
int ignorep = 0, client_ignorep = 0;
if (ddns_update_style != 2)
return 0;
/* Can only cope with IPv4 addrs at the moment. */
if (lease -> ip_addr . len != 4)
return 0;
memset(&d1, 0, sizeof(d1));
memset (&ddns_hostname, 0, sizeof (ddns_hostname));
memset (&ddns_domainname, 0, sizeof (ddns_domainname));
memset (&old_ddns_fwd_name, 0, sizeof (ddns_fwd_name));
memset (&ddns_fwd_name, 0, sizeof (ddns_fwd_name));
memset (&ddns_rev_name, 0, sizeof (ddns_rev_name));
memset (&ddns_dhcid, 0, sizeof (ddns_dhcid));
/* If we are allowed to accept the client's update of its own A
record, see if the client wants to update its own A record. */
if (!(oc = lookup_option(&server_universe, state->options,
SV_CLIENT_UPDATES)) ||
evaluate_boolean_option_cache(&client_ignorep, packet, lease, NULL,
packet->options, state->options,
&lease->scope, oc, MDL)) {
/* If there's no fqdn.no-client-update or if it's
nonzero, don't try to use the client-supplied
XXX */
if (!(oc = lookup_option (&fqdn_universe, packet -> options,
FQDN_SERVER_UPDATE)) ||
evaluate_boolean_option_cache (&ignorep, packet, lease,
(struct client_state *)0,
packet -> options,
state -> options,
&lease -> scope, oc, MDL))
goto noclient;
/* Win98 and Win2k will happily claim to be willing to
update an unqualified domain name. */
if (!(oc = lookup_option (&fqdn_universe, packet -> options,
FQDN_DOMAINNAME)))
goto noclient;
if (!(oc = lookup_option (&fqdn_universe, packet -> options,
FQDN_FQDN)) ||
!evaluate_option_cache (&ddns_fwd_name, packet, lease,
(struct client_state *)0,
packet -> options,
state -> options,
&lease -> scope, oc, MDL))
goto noclient;
server_updates_a = 0;
goto client_updates;
}
noclient:
/* If do-forward-updates is disabled, this basically means don't
do an update unless the client is participating, so if we get
here and do-forward-updates is disabled, we can stop. */
if ((oc = lookup_option (&server_universe, state -> options,
SV_DO_FORWARD_UPDATES)) &&
!evaluate_boolean_option_cache (&ignorep, packet, lease,
(struct client_state *)0,
packet -> options,
state -> options,
&lease -> scope, oc, MDL)) {
return 0;
}
/* If it's a static lease, then don't do the DNS update unless we're
specifically configured to do so. If the client asked to do its
own update and we allowed that, we don't do this test. */
if (lease -> flags & STATIC_LEASE) {
if (!(oc = lookup_option (&server_universe, state -> options,
SV_UPDATE_STATIC_LEASES)) ||
!evaluate_boolean_option_cache (&ignorep, packet, lease,
(struct client_state *)0,
packet -> options,
state -> options,
&lease -> scope, oc, MDL))
return 0;
}
/*
* Compute the name for the A record.
*/
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);
else
s1 = 0;
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);
else
s2 = 0;
if (s1 && s2) {
if (ddns_hostname.len + ddns_domainname.len > 253) {
log_error ("ddns_update: host.domain name too long");
goto out;
}
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;
}
}
client_updates:
/* See if there's a name already stored on the lease. */
if (find_bound_string (&old_ddns_fwd_name,
lease -> scope, "ddns-fwd-name")) {
/* If there is, see if it's different. */
if (old_ddns_fwd_name.len != ddns_fwd_name.len ||
memcmp (old_ddns_fwd_name.data, ddns_fwd_name.data,
old_ddns_fwd_name.len)) {
/* If the name is different, try to delete
the old A record. */
if (!ddns_removals (lease))
goto out;
/* If the delete succeeded, go install the new
record. */
goto in;
}
/* See if there's a DHCID on the lease. */
if (!find_bound_string (&ddns_dhcid,
lease -> scope, "ddns-txt")) {
/* If there's no DHCID, the update was probably
done with the old-style ad-hoc DDNS updates.
So if the expiry and release events look like
they're the same, run them. This should delete
the old DDNS data. */
if (old -> on_expiry == old -> on_release) {
execute_statements ((struct binding_value **)0,
(struct packet *)0, lease,
(struct client_state *)0,
(struct option_state *)0,
(struct option_state *)0,
&lease -> scope,
old -> on_expiry);
if (old -> on_expiry)
executable_statement_dereference
(&old -> on_expiry, MDL);
if (old -> on_release)
executable_statement_dereference
(&old -> on_release, MDL);
/* Now, install the DDNS data the new way. */
goto in;
}
} else
data_string_forget(&ddns_dhcid, MDL);
/* See if the administrator wants to do updates even
in cases where the update already appears to have been
done. */
if (!(oc = lookup_option (&server_universe, state -> options,
SV_UPDATE_OPTIMIZATION)) ||
evaluate_boolean_option_cache (&ignorep, packet, lease,
(struct client_state *)0,
packet -> options,
state -> options,
&lease -> scope, oc, MDL)) {
result = 1;
goto noerror;
}
/* If there's no "ddns-fwd-name" on the lease record, see if
* there's a ddns-client-fqdn indicating a previous client
* update (if it changes, we need to adjust the PTR).
*/
} else if (find_bound_string(&old_ddns_fwd_name, lease->scope,
"ddns-client-fqdn")) {
/* If the name is not different, no need to update
the PTR record. */
if (old_ddns_fwd_name.len == ddns_fwd_name.len &&
!memcmp (old_ddns_fwd_name.data, ddns_fwd_name.data,
old_ddns_fwd_name.len) &&
(!(oc = lookup_option (&server_universe,
state -> options,
SV_UPDATE_OPTIMIZATION)) ||
evaluate_boolean_option_cache (&ignorep, packet, lease,
(struct client_state *)0,
packet -> options,
state -> options,
&lease -> scope, oc,
MDL))) {
goto noerror;
}
}
in:
/* If we don't have a name that the client has been assigned, we
can just skip all this. */
if (!ddns_fwd_name.len)
goto out;
if (ddns_fwd_name.len > 255) {
log_error ("client provided fqdn: too long");
goto out;
}
/*
* Compute 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);
}
}
/* CC: see if we are configured NOT to do reverse ptr updates
*/
if ((oc = lookup_option (&server_universe, state -> options,
SV_DO_REVERSE_UPDATES)) &&
!evaluate_boolean_option_cache (&ignorep, packet, lease,
(struct client_state *)0,
packet -> options,
state -> options,
&lease -> scope, oc, MDL)) {
server_updates_ptr = 0;
}
/*
* Compute 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);
else
s1 = 0;
if (s1 && (d1.len > 238)) {
log_error ("ddns_update: Calculated rev domain name too long.");
s1 = 0;
data_string_forget (&d1, 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;
/* %Audit% Cannot exceed 17 bytes. %2004.06.17,Safe% */
sprintf ((char *)ddns_rev_name.buffer -> data,
"%u.%u.%u.%u.",
lease -> ip_addr . iabuf[3] & 0xff,
lease -> ip_addr . iabuf[2] & 0xff,
lease -> ip_addr . iabuf[1] & 0xff,
lease -> ip_addr . iabuf[0] & 0xff);
ddns_rev_name.len =
strlen ((const char *)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);
}
/*
* If we are updating the A record, compute the DHCID value.
*/
if (server_updates_a) {
if (lease -> uid && lease -> uid_len)
result = get_dhcid (&ddns_dhcid,
DHO_DHCP_CLIENT_IDENTIFIER,
lease -> uid, lease -> uid_len);
else
result = get_dhcid (&ddns_dhcid, 0,
lease -> hardware_addr.hbuf,
lease -> hardware_addr.hlen);
if (!result)
goto badfqdn;
}
/*
* Start the resolver, if necessary.
*/
if (!resolver_inited) {
minires_ninit (&resolver_state);
resolver_inited = 1;
resolver_state.retrans = 1;
resolver_state.retry = 1;
}
/*
* Perform updates.
*/
if (ddns_fwd_name.len && ddns_dhcid.len) {
unsigned conflict;
oc = lookup_option(&server_universe, state->options,
SV_DDNS_CONFLICT_DETECT);
if (!oc ||
evaluate_boolean_option_cache(&ignorep, packet, lease,
NULL, packet->options,
state->options,
&lease->scope, oc, MDL))
conflict = 1;
else
conflict = 0;
rcode1 = ddns_update_a (&ddns_fwd_name, lease -> ip_addr,
&ddns_dhcid, ddns_ttl, 0, conflict);
}
if (rcode1 == ISC_R_SUCCESS && server_updates_ptr) {
if (ddns_fwd_name.len && ddns_rev_name.len)
rcode2 = ddns_update_ptr (&ddns_fwd_name,
&ddns_rev_name, ddns_ttl);
} else
rcode2 = rcode1;
if (rcode1 == ISC_R_SUCCESS &&
(server_updates_a || rcode2 == ISC_R_SUCCESS)) {
bind_ds_value (&lease -> scope,
(server_updates_a
? "ddns-fwd-name" : "ddns-client-fqdn"),
&ddns_fwd_name);
if (server_updates_a)
bind_ds_value (&lease -> scope, "ddns-txt",
&ddns_dhcid);
}
if (rcode2 == ISC_R_SUCCESS && server_updates_ptr) {
bind_ds_value (&lease -> scope, "ddns-rev-name",
&ddns_rev_name);
}
noerror:
/*
* If fqdn-reply option is disabled in dhcpd.conf, then don't
* send the client an FQDN option at all, even if one was requested.
* (WinXP clients allegedly misbehave if the option is present,
* refusing to handle PTR updates themselves).
*/
if ((oc = lookup_option (&server_universe, state->options,
SV_FQDN_REPLY)) &&
!evaluate_boolean_option_cache (&ignorep, packet, lease,
(struct client_state *)0,
packet->options,
state->options,
&lease->scope, oc, MDL)) {
goto badfqdn;
/* If we're ignoring client updates, then we tell a sort of 'white
* lie'. We've already updated the name the server wants (per the
* config written by the server admin). Now let the client do as
* it pleases with the name they supplied (if any).
*
* We only form an FQDN option this way if the client supplied an
* FQDN option that had FQDN_SERVER_UPDATE set false.
*/
} else if (client_ignorep &&
(oc = lookup_option(&fqdn_universe, packet->options,
FQDN_SERVER_UPDATE)) &&
!evaluate_boolean_option_cache(&ignorep, packet, lease, NULL,
packet->options, state->options,
&lease->scope, oc, MDL)) {
oc = lookup_option(&fqdn_universe, packet->options, FQDN_FQDN);
if (oc && evaluate_option_cache(&d1, packet, lease, NULL,
packet->options, state->options,
&global_scope, oc, MDL)) {
if (d1.len == 0 ||
!buffer_allocate(&bp, d1.len + 5, MDL))
goto badfqdn;
/* Server pretends it is not updating. */
bp->data[0] = 0;
if (!save_option_buffer(&fqdn_universe, state->options,
bp, &bp->data[0], 1,
FQDN_SERVER_UPDATE, 0))
goto badfqdn;
/* Client is encouraged to update. */
bp->data[1] = 0;
if (!save_option_buffer(&fqdn_universe, state->options,
bp, &bp->data[1], 1,
FQDN_NO_CLIENT_UPDATE, 0))
goto badfqdn;
/* Use the encoding of client's FQDN option. */
oc = lookup_option(&fqdn_universe, packet->options,
FQDN_ENCODED);
if (oc && evaluate_boolean_option_cache(&ignorep,
packet, lease, NULL,
packet->options,
state->options,
&lease->scope, oc,
MDL))
bp->data[2] = 1; /* FQDN is encoded. */
else
bp->data[2] = 0; /* FQDN is not encoded. */
if (!save_option_buffer(&fqdn_universe, state->options,
bp, &bp->data[2], 1,
FQDN_ENCODED, 0))
goto badfqdn;
/* Current FQDN drafts indicate 255 is mandatory. */
bp->data[3] = 255;
if (!save_option_buffer(&fqdn_universe, state->options,
bp, &bp->data[3], 1,
FQDN_RCODE1, 0))
goto badfqdn;
bp->data[4] = 255;
if (!save_option_buffer(&fqdn_universe, state->options,
bp, &bp->data[4], 1,
FQDN_RCODE2, 0))
goto badfqdn;
/* Copy in the FQDN supplied by the client. Note well
* that the format of this option in the cache is going
* to be in text format. If the fqdn supplied by the
* client is encoded, it is decoded into the option
* cache when parsed out of the packet. It will be
* re-encoded when the option is assembled to be
* transmitted if the client elects that encoding.
*/
memcpy(&bp->data[5], d1.data, d1.len);
if (!save_option_buffer(&fqdn_universe, state->options,
bp, &bp->data[5], 1,
FQDN_FQDN, 0))
goto badfqdn;
data_string_forget(&d1, MDL);
}
/* Set up the outgoing FQDN option if there was an incoming
* FQDN option. If there's a valid FQDN option, there MUST
* be an FQDN_SERVER_UPDATES suboption, it's part of the fixed
* length head of the option contents, so we test the latter
* to detect the presence of the former.
*/
} else if ((oc = lookup_option(&fqdn_universe, packet->options,
FQDN_ENCODED)) &&
buffer_allocate(&bp, ddns_fwd_name.len + 5, MDL)) {
bp -> data [0] = server_updates_a;
if (!save_option_buffer (&fqdn_universe, state -> options,
bp, &bp -> data [0], 1,
FQDN_SERVER_UPDATE, 0))
goto badfqdn;
bp -> data [1] = server_updates_a;
if (!save_option_buffer (&fqdn_universe, state -> options,
bp, &bp -> data [1], 1,
FQDN_NO_CLIENT_UPDATE, 0))
goto badfqdn;
/* Do the same encoding the client did. */
if (evaluate_boolean_option_cache(&ignorep, packet, lease,
NULL, packet->options,
state->options,
&lease->scope, oc, MDL))
bp -> data [2] = 1;
else
bp -> data [2] = 0;
if (!save_option_buffer (&fqdn_universe, state -> options,
bp, &bp -> data [2], 1,
FQDN_ENCODED, 0))
goto badfqdn;
bp -> data [3] = isc_rcode_to_ns (rcode1);
if (!save_option_buffer (&fqdn_universe, state -> options,
bp, &bp -> data [3], 1,
FQDN_RCODE1, 0))
goto badfqdn;
bp -> data [4] = isc_rcode_to_ns (rcode2);
if (!save_option_buffer (&fqdn_universe, state -> options,
bp, &bp -> data [4], 1,
FQDN_RCODE2, 0))
goto badfqdn;
if (ddns_fwd_name.len) {
memcpy (&bp -> data [5],
ddns_fwd_name.data, ddns_fwd_name.len);
if (!save_option_buffer (&fqdn_universe, state -> options,
bp, &bp -> data [5],
ddns_fwd_name.len,
FQDN_FQDN, 0))
goto badfqdn;
}
}
badfqdn:
out:
/*
* Final cleanup.
*/
data_string_forget(&d1, MDL);
data_string_forget(&ddns_hostname, MDL);
data_string_forget(&ddns_domainname, MDL);
data_string_forget(&old_ddns_fwd_name, MDL);
data_string_forget(&ddns_fwd_name, MDL);
data_string_forget(&ddns_rev_name, MDL);
data_string_forget(&ddns_dhcid, MDL);
if (bp)
buffer_dereference(&bp, MDL);
return result;
}
/* Determine what, if any, forward and reverse updates need to be
* performed, and carry them through.
*/
int
ddns_updates(struct packet *packet, struct lease *lease, struct lease *old,
struct iasubopt *lease6, struct iasubopt *old6,
struct option_state *options)
{
unsigned long ddns_ttl = DEFAULT_DDNS_TTL;
struct data_string ddns_hostname;
struct data_string ddns_domainname;
struct data_string old_ddns_fwd_name;
struct data_string ddns_fwd_name;
struct data_string ddns_rev_name;
struct data_string ddns_dhcid;
struct binding_scope **scope;
struct iaddr addr;
struct data_string d1;
struct option_cache *oc;
int s1, s2;
int result = 0;
isc_result_t rcode1 = ISC_R_SUCCESS, rcode2 = ISC_R_SUCCESS;
int server_updates_a = 1;
int server_updates_ptr = 1;
struct buffer *bp = (struct buffer *)0;
int ignorep = 0, client_ignorep = 0;
int rev_name_len;
int i;
if (ddns_update_style != 2)
return 0;
if (lease != NULL) {
scope = &(lease->scope);
addr = lease->ip_addr;
} else if (lease6 != NULL) {
scope = &(lease6->scope);
memcpy(addr.iabuf, lease6->addr.s6_addr, 16);
addr.len = 16;
} else {
log_fatal("Impossible condition at %s:%d.", MDL);
/* Silence compiler warnings. */
return 0;
}
memset(&d1, 0, sizeof(d1));
memset (&ddns_hostname, 0, sizeof (ddns_hostname));
memset (&ddns_domainname, 0, sizeof (ddns_domainname));
memset (&old_ddns_fwd_name, 0, sizeof (ddns_fwd_name));
memset (&ddns_fwd_name, 0, sizeof (ddns_fwd_name));
memset (&ddns_rev_name, 0, sizeof (ddns_rev_name));
memset (&ddns_dhcid, 0, sizeof (ddns_dhcid));
/* If we are allowed to accept the client's update of its own A
record, see if the client wants to update its own A record. */
if (!(oc = lookup_option(&server_universe, options,
SV_CLIENT_UPDATES)) ||
evaluate_boolean_option_cache(&client_ignorep, packet, lease, NULL,
packet->options, options, scope,
oc, MDL)) {
/* If there's no fqdn.no-client-update or if it's
nonzero, don't try to use the client-supplied
XXX */
if (!(oc = lookup_option (&fqdn_universe, packet -> options,
FQDN_SERVER_UPDATE)) ||
evaluate_boolean_option_cache(&ignorep, packet, lease,
NULL, packet->options,
options, scope, oc, MDL))
goto noclient;
/* Win98 and Win2k will happily claim to be willing to
update an unqualified domain name. */
if (!(oc = lookup_option (&fqdn_universe, packet -> options,
FQDN_DOMAINNAME)))
goto noclient;
if (!(oc = lookup_option (&fqdn_universe, packet -> options,
FQDN_FQDN)) ||
!evaluate_option_cache(&ddns_fwd_name, packet, lease,
NULL, packet->options,
options, scope, oc, MDL))
goto noclient;
server_updates_a = 0;
goto client_updates;
}
noclient:
/* If do-forward-updates is disabled, this basically means don't
do an update unless the client is participating, so if we get
here and do-forward-updates is disabled, we can stop. */
if ((oc = lookup_option (&server_universe, options,
SV_DO_FORWARD_UPDATES)) &&
!evaluate_boolean_option_cache(&ignorep, packet, lease,
NULL, packet->options,
options, scope, oc, MDL)) {
return 0;
}
/* If it's a static lease, then don't do the DNS update unless we're
specifically configured to do so. If the client asked to do its
own update and we allowed that, we don't do this test. */
/* XXX: note that we cannot detect static DHCPv6 leases. */
if ((lease != NULL) && (lease->flags & STATIC_LEASE)) {
if (!(oc = lookup_option(&server_universe, options,
SV_UPDATE_STATIC_LEASES)) ||
!evaluate_boolean_option_cache(&ignorep, packet, lease,
NULL, packet->options,
options, scope, oc, MDL))
return 0;
}
/*
* Compute the name for the A record.
*/
oc = lookup_option(&server_universe, options, SV_DDNS_HOST_NAME);
if (oc)
s1 = evaluate_option_cache(&ddns_hostname, packet, lease,
NULL, packet->options,
options, scope, oc, MDL);
else
s1 = 0;
oc = lookup_option(&server_universe, options, SV_DDNS_DOMAIN_NAME);
if (oc)
s2 = evaluate_option_cache(&ddns_domainname, packet, lease,
NULL, packet->options,
options, scope, oc, MDL);
else
s2 = 0;
if (s1 && s2) {
if (ddns_hostname.len + ddns_domainname.len > 253) {
log_error ("ddns_update: host.domain name too long");
goto out;
}
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;
}
}
client_updates:
/* See if there's a name already stored on the lease. */
if (find_bound_string(&old_ddns_fwd_name, *scope, "ddns-fwd-name")) {
/* If there is, see if it's different. */
if (old_ddns_fwd_name.len != ddns_fwd_name.len ||
memcmp (old_ddns_fwd_name.data, ddns_fwd_name.data,
old_ddns_fwd_name.len)) {
/* If the name is different, try to delete
the old A record. */
if (!ddns_removals(lease, lease6))
goto out;
/* If the delete succeeded, go install the new
record. */
goto in;
}
/* See if there's a DHCID on the lease, and if not
* then potentially look for 'on events' for ad-hoc ddns.
*/
if (!find_bound_string(&ddns_dhcid, *scope, "ddns-txt") &&
(old != NULL)) {
/* If there's no DHCID, the update was probably
done with the old-style ad-hoc DDNS updates.
So if the expiry and release events look like
they're the same, run them. This should delete
the old DDNS data. */
if (old -> on_expiry == old -> on_release) {
execute_statements(NULL, NULL, lease, NULL,
NULL, NULL, scope,
old->on_expiry);
if (old -> on_expiry)
executable_statement_dereference
(&old -> on_expiry, MDL);
if (old -> on_release)
executable_statement_dereference
(&old -> on_release, MDL);
/* Now, install the DDNS data the new way. */
goto in;
}
} else
data_string_forget(&ddns_dhcid, MDL);
/* See if the administrator wants to do updates even
in cases where the update already appears to have been
done. */
if (!(oc = lookup_option(&server_universe, options,
SV_UPDATE_OPTIMIZATION)) ||
evaluate_boolean_option_cache(&ignorep, packet, lease,
NULL, packet->options,
options, scope, oc, MDL)) {
result = 1;
goto noerror;
}
/* If there's no "ddns-fwd-name" on the lease record, see if
* there's a ddns-client-fqdn indicating a previous client
* update (if it changes, we need to adjust the PTR).
*/
} else if (find_bound_string(&old_ddns_fwd_name, *scope,
"ddns-client-fqdn")) {
/* If the name is not different, no need to update
the PTR record. */
if (old_ddns_fwd_name.len == ddns_fwd_name.len &&
!memcmp (old_ddns_fwd_name.data, ddns_fwd_name.data,
old_ddns_fwd_name.len) &&
(!(oc = lookup_option(&server_universe, options,
SV_UPDATE_OPTIMIZATION)) ||
evaluate_boolean_option_cache(&ignorep, packet, lease,
NULL, packet->options,
options, scope, oc, MDL))) {
goto noerror;
}
}
in:
/* If we don't have a name that the client has been assigned, we
can just skip all this. */
if (!ddns_fwd_name.len)
goto out;
if (ddns_fwd_name.len > 255) {
log_error ("client provided fqdn: too long");
goto out;
}
/*
* Compute the RR TTL.
*/
ddns_ttl = DEFAULT_DDNS_TTL;
if ((oc = lookup_option(&server_universe, options, SV_DDNS_TTL))) {
if (evaluate_option_cache(&d1, packet, lease, NULL,
packet->options, options, scope,
oc, MDL)) {
if (d1.len == sizeof (u_int32_t))
ddns_ttl = getULong (d1.data);
data_string_forget (&d1, MDL);
}
}
/*
* Compute the reverse IP name, starting with the domain name.
*/
oc = lookup_option(&server_universe, options, SV_DDNS_REV_DOMAIN_NAME);
if (oc)
s1 = evaluate_option_cache(&d1, packet, lease, NULL,
packet->options, options,
scope, oc, MDL);
else
s1 = 0;
/*
* Figure out the length of the part of the name that depends
* on the address.
*/
if (addr.len == 4) {
char buf[17];
/* XXX: WOW this is gross. */
rev_name_len = snprintf(buf, sizeof(buf), "%u.%u.%u.%u.",
addr.iabuf[3] & 0xff,
addr.iabuf[2] & 0xff,
addr.iabuf[1] & 0xff,
addr.iabuf[0] & 0xff) + 1;
if (s1) {
rev_name_len += d1.len;
if (rev_name_len > 255) {
log_error("ddns_update: Calculated rev domain "
"name too long.");
s1 = 0;
data_string_forget(&d1, MDL);
}
}
} else if (addr.len == 16) {
/*
* IPv6 reverse names are always the same length, with
* 32 hex characters separated by dots.
*/
rev_name_len = sizeof("0.1.2.3.4.5.6.7."
"8.9.a.b.c.d.e.f."
"0.1.2.3.4.5.6.7."
"8.9.a.b.c.d.e.f."
"ip6.arpa.");
/* Set s1 to make sure we gate into updates. */
s1 = 1;
} else {
log_fatal("invalid address length %d", addr.len);
/* Silence compiler warnings. */
return 0;
}
/* See if we are configured NOT to do reverse ptr updates */
if ((oc = lookup_option(&server_universe, options,
SV_DO_REVERSE_UPDATES)) &&
!evaluate_boolean_option_cache(&ignorep, packet, lease, NULL,
packet->options, options,
scope, oc, MDL)) {
server_updates_ptr = 0;
}
if (s1) {
i=buffer_allocate(&ddns_rev_name.buffer, rev_name_len, MDL);
if(!i){
log_error("buffer_allocate failed!\n");
}
if (ddns_rev_name.buffer != NULL) {
ddns_rev_name.data = ddns_rev_name.buffer->data;
if (addr.len == 4) {
ddns_rev_name.len =
sprintf((char *)ddns_rev_name.buffer->data,
"%u.%u.%u.%u.",
addr.iabuf[3] & 0xff,
addr.iabuf[2] & 0xff,
addr.iabuf[1] & 0xff,
addr.iabuf[0] & 0xff);
/*
* d1.data may be opaque, garbage bytes, from
* user (mis)configuration.
*/
data_string_append(&ddns_rev_name, &d1);
ddns_rev_name.buffer->data[ddns_rev_name.len] =
'\0';
} else if (addr.len == 16) {
char *p = (char *)&ddns_rev_name.buffer->data;
unsigned char *a = addr.iabuf + 15;
for (i=0; i<16; i++) {
sprintf(p, "%x.%x.",
(*a & 0xF), ((*a >> 4) & 0xF));
p += 4;
a -= 1;
}
strcat(p, "ip6.arpa.");
ddns_rev_name.len =
strlen((const char *)ddns_rev_name.data);
}
ddns_rev_name.terminated = 1;
}
/* Determine what, if any, forward and reverse updates need to be
* performed, and carry them through.
*/
int
ddns_updates(struct packet *packet, struct lease *lease, struct lease *old,
struct iasubopt *lease6, struct iasubopt *old6,
struct option_state *options)
{
unsigned long ddns_ttl = DEFAULT_DDNS_TTL;
struct data_string ddns_hostname;
struct data_string ddns_domainname;
struct data_string old_ddns_fwd_name;
struct data_string ddns_fwd_name;
//struct data_string ddns_rev_name;
struct data_string ddns_dhcid;
struct binding_scope **scope = NULL;
//struct iaddr addr;
struct data_string d1;
struct option_cache *oc;
int s1, s2;
int result = 0;
isc_result_t rcode1 = ISC_R_SUCCESS;
int server_updates_a = 1;
//int server_updates_ptr = 1;
struct buffer *bp = (struct buffer *)0;
int ignorep = 0, client_ignorep = 0;
int rev_name_len;
int i;
dhcp_ddns_cb_t *ddns_cb;
int do_remove = 0;
if (ddns_update_style != 2)
return 0;
/*
* sigh, I want to cancel any previous udpates before we do anything
* else but this means we need to deal with the lease vs lease6
* question twice.
* If there is a ddns request already outstanding cancel it.
*/
if (lease != NULL) {
if ((old != NULL) && (old->ddns_cb != NULL)) {
ddns_cancel(old->ddns_cb);
old->ddns_cb = NULL;
}
} else if (lease6 != NULL) {
if ((old6 != NULL) && (old6->ddns_cb != NULL)) {
ddns_cancel(old->ddns_cb);
old6->ddns_cb = NULL;
}
} else {
log_fatal("Impossible condition at %s:%d.", MDL);
/* Silence compiler warnings. */
result = 0;
return(0);
}
/* allocate our control block */
ddns_cb = ddns_cb_alloc(MDL);
if (ddns_cb == NULL) {
return(0);
}
/* assume that we shall update both the A and ptr records */
ddns_cb->flags = DDNS_UPDATE_ADDR | DDNS_UPDATE_PTR;
if (lease != NULL) {
scope = &(lease->scope);
ddns_cb->address = lease->ip_addr;
} else if (lease6 != NULL) {
scope = &(lease6->scope);
memcpy(ddns_cb->address.iabuf, lease6->addr.s6_addr, 16);
ddns_cb->address.len = 16;
}
memset (&d1, 0, sizeof(d1));
memset (&ddns_hostname, 0, sizeof (ddns_hostname));
memset (&ddns_domainname, 0, sizeof (ddns_domainname));
memset (&old_ddns_fwd_name, 0, sizeof (ddns_fwd_name));
memset (&ddns_fwd_name, 0, sizeof (ddns_fwd_name));
//memset (&ddns_rev_name, 0, sizeof (ddns_rev_name));
memset (&ddns_dhcid, 0, sizeof (ddns_dhcid));
/* If we are allowed to accept the client's update of its own A
record, see if the client wants to update its own A record. */
if (!(oc = lookup_option(&server_universe, options,
SV_CLIENT_UPDATES)) ||
evaluate_boolean_option_cache(&client_ignorep, packet, lease, NULL,
packet->options, options, scope,
oc, MDL)) {
/* If there's no fqdn.no-client-update or if it's
nonzero, don't try to use the client-supplied
XXX */
if (!(oc = lookup_option (&fqdn_universe, packet -> options,
FQDN_SERVER_UPDATE)) ||
evaluate_boolean_option_cache(&ignorep, packet, lease,
NULL, packet->options,
options, scope, oc, MDL))
goto noclient;
/* Win98 and Win2k will happily claim to be willing to
update an unqualified domain name. */
if (!(oc = lookup_option (&fqdn_universe, packet -> options,
FQDN_DOMAINNAME)))
goto noclient;
if (!(oc = lookup_option (&fqdn_universe, packet -> options,
FQDN_FQDN)) ||
!evaluate_option_cache(&ddns_fwd_name, packet, lease,
NULL, packet->options,
options, scope, oc, MDL))
goto noclient;
ddns_cb->flags &= ~DDNS_UPDATE_ADDR;
server_updates_a = 0;
goto client_updates;
}
noclient:
/* If do-forward-updates is disabled, this basically means don't
do an update unless the client is participating, so if we get
here and do-forward-updates is disabled, we can stop. */
if ((oc = lookup_option (&server_universe, options,
SV_DO_FORWARD_UPDATES)) &&
!evaluate_boolean_option_cache(&ignorep, packet, lease,
NULL, packet->options,
options, scope, oc, MDL)) {
goto out;
}
/* If it's a static lease, then don't do the DNS update unless we're
specifically configured to do so. If the client asked to do its
own update and we allowed that, we don't do this test. */
/* XXX: note that we cannot detect static DHCPv6 leases. */
if ((lease != NULL) && (lease->flags & STATIC_LEASE)) {
if (!(oc = lookup_option(&server_universe, options,
SV_UPDATE_STATIC_LEASES)) ||
!evaluate_boolean_option_cache(&ignorep, packet, lease,
NULL, packet->options,
options, scope, oc, MDL))
goto out;
}
/*
* Compute the name for the A record.
*/
oc = lookup_option(&server_universe, options, SV_DDNS_HOST_NAME);
if (oc)
s1 = evaluate_option_cache(&ddns_hostname, packet, lease,
NULL, packet->options,
options, scope, oc, MDL);
else
s1 = 0;
oc = lookup_option(&server_universe, options, SV_DDNS_DOMAIN_NAME);
if (oc)
s2 = evaluate_option_cache(&ddns_domainname, packet, lease,
NULL, packet->options,
options, scope, oc, MDL);
else
s2 = 0;
if (s1 && s2) {
if (ddns_hostname.len + ddns_domainname.len > 253) {
log_error ("ddns_update: host.domain name too long");
goto out;
}
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;
}
}
client_updates:
/* See if there's a name already stored on the lease. */
if (find_bound_string(&old_ddns_fwd_name, *scope, "ddns-fwd-name")) {
/* If there is, see if it's different. */
if (old_ddns_fwd_name.len != ddns_fwd_name.len ||
memcmp (old_ddns_fwd_name.data, ddns_fwd_name.data,
old_ddns_fwd_name.len)) {
/*
* If the name is different, mark the old record
* for deletion and continue getting the new info.
*/
do_remove = 1;
goto in;
}
/* See if there's a DHCID on the lease, and if not
* then potentially look for 'on events' for ad-hoc ddns.
*/
if (!find_bound_string(&ddns_dhcid, *scope, "ddns-txt") &&
(old != NULL)) {
/* If there's no DHCID, the update was probably
done with the old-style ad-hoc DDNS updates.
So if the expiry and release events look like
they're the same, run them. This should delete
the old DDNS data. */
if (old -> on_expiry == old -> on_release) {
execute_statements(NULL, NULL, lease, NULL,
NULL, NULL, scope,
old->on_expiry);
if (old -> on_expiry)
executable_statement_dereference
(&old -> on_expiry, MDL);
if (old -> on_release)
executable_statement_dereference
(&old -> on_release, MDL);
/* Now, install the DDNS data the new way. */
goto in;
}
} else
data_string_forget(&ddns_dhcid, MDL);
/* See if the administrator wants to do updates even
in cases where the update already appears to have been
done. */
if (!(oc = lookup_option(&server_universe, options,
SV_UPDATE_OPTIMIZATION)) ||
evaluate_boolean_option_cache(&ignorep, packet, lease,
NULL, packet->options,
options, scope, oc, MDL)) {
result = 1;
goto noerror;
}
/* If there's no "ddns-fwd-name" on the lease record, see if
* there's a ddns-client-fqdn indicating a previous client
* update (if it changes, we need to adjust the PTR).
*/
} else if (find_bound_string(&old_ddns_fwd_name, *scope,
"ddns-client-fqdn")) {
/* If the name is not different, no need to update
the PTR record. */
if (old_ddns_fwd_name.len == ddns_fwd_name.len &&
!memcmp (old_ddns_fwd_name.data, ddns_fwd_name.data,
old_ddns_fwd_name.len) &&
(!(oc = lookup_option(&server_universe, options,
SV_UPDATE_OPTIMIZATION)) ||
evaluate_boolean_option_cache(&ignorep, packet, lease,
NULL, packet->options,
options, scope, oc, MDL))) {
goto noerror;
}
}
in:
/* If we don't have a name that the client has been assigned, we
can just skip all this. */
if ((!ddns_fwd_name.len) || (ddns_fwd_name.len > 255)) {
if (ddns_fwd_name.len > 255) {
log_error ("client provided fqdn: too long");
}
/* If desired do the removals */
if (do_remove != 0) {
(void) ddns_removals(lease, lease6, NULL);
}
goto out;
}
/*
* Compute the RR TTL.
*
* We have two ways of computing the TTL.
* The old behavior was to allow for the customer to set up
* the option or to default things. For v4 this was 1/2
* of the lease time, for v6 this was DEFAULT_DDNS_TTL.
* The new behavior continues to allow the customer to set
* up an option but the defaults are a little different.
* We now use 1/2 of the (preferred) lease time for both
* v4 and v6 and cap them at a maximum value.
* If the customer chooses to use an experession that references
* part of the lease the v6 value will be the default as there
* isn't a lease available for v6.
*/
ddns_ttl = DEFAULT_DDNS_TTL;
if (lease != NULL) {
if (lease->ends <= cur_time) {
ddns_ttl = 0;
} else {
ddns_ttl = (lease->ends - cur_time)/2;
}
}
#ifndef USE_OLD_DDNS_TTL
else if (lease6 != NULL) {
ddns_ttl = lease6->prefer/2;
}
if (ddns_ttl > MAX_DEFAULT_DDNS_TTL) {
ddns_ttl = MAX_DEFAULT_DDNS_TTL;
}
#endif
if ((oc = lookup_option(&server_universe, options, SV_DDNS_TTL))) {
if (evaluate_option_cache(&d1, packet, lease, NULL,
packet->options, options,
scope, oc, MDL)) {
if (d1.len == sizeof (u_int32_t))
ddns_ttl = getULong (d1.data);
data_string_forget (&d1, MDL);
}
}
ddns_cb->ttl = ddns_ttl;
/*
* Compute the reverse IP name, starting with the domain name.
*/
oc = lookup_option(&server_universe, options, SV_DDNS_REV_DOMAIN_NAME);
if (oc)
s1 = evaluate_option_cache(&d1, packet, lease, NULL,
packet->options, options,
scope, oc, MDL);
else
s1 = 0;
/*
* Figure out the length of the part of the name that depends
* on the address.
*/
if (ddns_cb->address.len == 4) {
char buf[17];
/* XXX: WOW this is gross. */
rev_name_len = snprintf(buf, sizeof(buf), "%u.%u.%u.%u.",
ddns_cb->address.iabuf[3] & 0xff,
ddns_cb->address.iabuf[2] & 0xff,
ddns_cb->address.iabuf[1] & 0xff,
ddns_cb->address.iabuf[0] & 0xff) + 1;
if (s1) {
rev_name_len += d1.len;
if (rev_name_len > 255) {
log_error("ddns_update: Calculated rev domain "
"name too long.");
s1 = 0;
data_string_forget(&d1, MDL);
}
}
} else if (ddns_cb->address.len == 16) {
/*
* IPv6 reverse names are always the same length, with
* 32 hex characters separated by dots.
*/
rev_name_len = sizeof("0.1.2.3.4.5.6.7."
"8.9.a.b.c.d.e.f."
"0.1.2.3.4.5.6.7."
"8.9.a.b.c.d.e.f."
"ip6.arpa.");
/* Set s1 to make sure we gate into updates. */
s1 = 1;
} else {
log_fatal("invalid address length %d", ddns_cb->address.len);
/* Silence compiler warnings. */
return 0;
}
/* See if we are configured NOT to do reverse ptr updates */
if ((oc = lookup_option(&server_universe, options,
SV_DO_REVERSE_UPDATES)) &&
!evaluate_boolean_option_cache(&ignorep, packet, lease, NULL,
packet->options, options,
scope, oc, MDL)) {
ddns_cb->flags &= ~DDNS_UPDATE_PTR;
}
if (s1) {
buffer_allocate(&ddns_cb->rev_name.buffer, rev_name_len, MDL);
if (ddns_cb->rev_name.buffer != NULL) {
struct data_string *rname = &ddns_cb->rev_name;
rname->data = rname->buffer->data;
if (ddns_cb->address.len == 4) {
rname->len =
sprintf((char *)rname->buffer->data,
"%u.%u.%u.%u.",
ddns_cb->address.iabuf[3] & 0xff,
ddns_cb->address.iabuf[2] & 0xff,
ddns_cb->address.iabuf[1] & 0xff,
ddns_cb->address.iabuf[0] & 0xff);
/*
* d1.data may be opaque, garbage bytes, from
* user (mis)configuration.
*/
data_string_append(rname, &d1);
rname->buffer->data[rname->len] = '\0';
} else if (ddns_cb->address.len == 16) {
char *p = (char *)&rname->buffer->data;
unsigned char *a = ddns_cb->address.iabuf + 15;
for (i=0; i<16; i++) {
sprintf(p, "%x.%x.",
(*a & 0xF), ((*a >> 4) & 0xF));
p += 4;
a -= 1;
}
strcat(p, "ip6.arpa.");
rname->len = strlen((const char *)rname->data);
}
rname->terminated = 1;
}
if (d1.data != NULL)
data_string_forget(&d1, MDL);
}