void
lease_pinged(struct iaddr from, u_int8_t *packet, int length)
{
struct lease *lp;
/*
* Don't try to look up a pinged lease if we aren't trying to
* ping one - otherwise somebody could easily make us churn by
* just forging repeated ICMP EchoReply packets for us to look
* up.
*/
if (!outstanding_pings)
return;
lp = find_lease_by_ip_addr(from);
if (!lp) {
note("unexpected ICMP Echo Reply from %s", piaddr(from));
return;
}
if (!lp->state && !lp->releasing) {
warning("ICMP Echo Reply for %s arrived late or is spurious.",
piaddr(from));
return;
}
/* At this point it looks like we pinged a lease and got a
* response, which shouldn't have happened.
* if it did it's either one of two two cases:
* 1 - we pinged this lease before offering it and
* something answered, so we abandon it.
* 2 - we pinged this lease before releasing it
* and something answered, so we don't release it.
*/
if (lp->releasing) {
warning("IP address %s answers a ping after sending a release",
piaddr(lp->ip_addr));
warning("Possible release spoof - Not releasing address %s",
piaddr(lp->ip_addr));
lp->releasing = 0;
} else {
free_lease_state(lp->state, "lease_pinged");
lp->state = NULL;
abandon_lease(lp, "pinged before offer");
}
cancel_timeout(lease_ping_timeout, lp);
--outstanding_pings;
}
void relinquish_lease_hunks ()
{
struct lease *c, *n, **p;
int i;
/* Account for all the leases on the free list. */
for (n = lease_hunks; n; n = n->next) {
for (i = 1; i < n->starts + 1; i++) {
p = &free_leases;
for (c = free_leases; c; c = c->next) {
if (c == &n[i]) {
*p = c->next;
n->ends++;
break;
}
p = &c->next;
}
if (!c) {
log_info("lease %s refcnt %d",
piaddr (n[i].ip_addr), n[i].refcnt);
#if defined (DEBUG_RC_HISTORY)
dump_rc_history(&n[i]);
#endif
}
}
}
for (c = lease_hunks; c; c = n) {
n = c->next;
if (c->ends != c->starts) {
log_info("lease hunk %lx leases %ld free %ld",
(unsigned long)c, (unsigned long)(c->starts),
(unsigned long)(c->ends));
}
dfree(c, MDL);
}
/* Free all the rogue leases. */
for (c = free_leases; c; c = n) {
n = c->next;
dfree(c, MDL);
}
}
/*
* 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) {
if (lq->client_id.len > 0) {
data_string_forget(&lq->client_id, MDL);
}
if (lq->server_id.len > 0) {
data_string_forget(&lq->server_id, MDL);
}
if (lq->lq_query.len > 0) {
data_string_forget(&lq->lq_query, MDL);
}
}
return ret_val;
}
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;
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.
*/
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));
/*
* Leasequery packets are be sent to the gateway address.
*/
to.sin_addr = packet->raw->giaddr;
if (packet->raw->giaddr.s_addr != htonl(INADDR_LOOPBACK)) {
to.sin_port = local_port;
} 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);
}
/*
* Write the specified lease to the current lease database file.
*/
int
write_lease(struct lease *lease)
{
char tbuf[26]; /* "w yyyy/mm/dd hh:mm:ss UTC" */
size_t rsltsz;
int errors = 0;
int i;
if (counting)
++count;
if (fprintf(db_file, "lease %s {\n", piaddr(lease->ip_addr)) == -1)
++errors;
rsltsz = strftime(tbuf, sizeof(tbuf), DB_TIMEFMT,
gmtime(&lease->starts));
if (rsltsz == 0 || fprintf(db_file, "\tstarts %s;\n", tbuf) == -1)
errors++;
rsltsz = strftime(tbuf, sizeof(tbuf), DB_TIMEFMT,
gmtime(&lease->ends));
if (rsltsz == 0 || fprintf(db_file, "\tends %s;\n", tbuf) == -1)
errors++;
if (lease->hardware_addr.hlen) {
if (fprintf(db_file, "\thardware %s %s;",
hardware_types[lease->hardware_addr.htype],
print_hw_addr(lease->hardware_addr.htype,
lease->hardware_addr.hlen,
lease->hardware_addr.haddr)) == -1)
++errors;
}
if (lease->uid_len) {
int j;
if (fprintf(db_file, "\n\tuid %2.2x", lease->uid[0]) == -1)
++errors;
for (j = 1; j < lease->uid_len; j++) {
if (fprintf(db_file, ":%2.2x", lease->uid[j]) == -1)
++errors;
}
if (fputc(';', db_file) == EOF)
++errors;
}
if (lease->flags & BOOTP_LEASE) {
if (fprintf(db_file, "\n\tdynamic-bootp;") == -1)
++errors;
}
if (lease->flags & ABANDONED_LEASE) {
if (fprintf(db_file, "\n\tabandoned;") == -1)
++errors;
}
if (lease->client_hostname) {
for (i = 0; lease->client_hostname[i]; i++)
if (lease->client_hostname[i] < 33 ||
lease->client_hostname[i] > 126)
goto bad_client_hostname;
if (fprintf(db_file, "\n\tclient-hostname \"%s\";",
lease->client_hostname) == -1)
++errors;
}
bad_client_hostname:
if (lease->hostname) {
for (i = 0; lease->hostname[i]; i++)
if (lease->hostname[i] < 33 ||
lease->hostname[i] > 126)
goto bad_hostname;
if (fprintf(db_file, "\n\thostname \"%s\";",
lease->hostname) == -1)
++errors;
}
bad_hostname:
if (fputs("\n}\n", db_file) == EOF)
++errors;
if (errors)
note("write_lease: unable to write lease %s",
piaddr(lease->ip_addr));
return (!errors);
}
void
bootp(struct packet *packet)
{
struct host_decl *hp, *host = NULL;
struct packet outgoing;
struct dhcp_packet raw;
struct sockaddr_in to;
struct in_addr from;
struct tree_cache *options[256];
struct subnet *subnet = NULL;
struct lease *lease;
struct iaddr ip_address;
int i;
if (packet->raw->op != BOOTREQUEST)
return;
note("BOOTREQUEST from %s via %s%s", print_hw_addr(packet->raw->htype,
packet->raw->hlen, packet->raw->chaddr),
packet->raw->giaddr.s_addr ? inet_ntoa(packet->raw->giaddr) :
packet->interface->name,
packet->options_valid ? "" : " (non-rfc1048)");
if (!locate_network(packet))
return;
hp = find_hosts_by_haddr(packet->raw->htype, packet->raw->chaddr,
packet->raw->hlen);
lease = find_lease(packet, packet->shared_network, 0);
/*
* Find an IP address in the host_decl that matches the specified
* network.
*/
if (hp)
subnet = find_host_for_network(&hp, &ip_address,
packet->shared_network);
if (!subnet) {
/*
* We didn't find an applicable host declaration. Just in case
* we may be able to dynamically assign an address, see if
* there's a host declaration that doesn't have an ip address
* associated with it.
*/
if (hp)
for (; hp; hp = hp->n_ipaddr)
if (!hp->fixed_addr) {
host = hp;
break;
}
if (host && (!host->group->allow_booting)) {
note("Ignoring excluded BOOTP client %s", host->name ?
host->name : print_hw_addr (packet->raw->htype,
packet->raw->hlen, packet->raw->chaddr));
return;
}
if (host && (!host->group->allow_bootp)) {
note("Ignoring BOOTP request from client %s",
host->name ? host->name :
print_hw_addr(packet->raw->htype,
packet->raw->hlen, packet->raw->chaddr));
return;
}
/*
* If we've been told not to boot unknown clients, and we didn't
* find any host record for this client, ignore it.
*/
if (!host &&
!(packet->shared_network->group->boot_unknown_clients)) {
note("Ignoring unknown BOOTP client %s via %s",
print_hw_addr(packet->raw->htype,
packet->raw->hlen, packet->raw->chaddr),
packet->raw->giaddr.s_addr ?
inet_ntoa(packet->raw->giaddr) :
packet->interface->name);
return;
}
/*
* If we've been told not to boot with bootp on this network,
* ignore it.
*/
if (!host &&
!(packet->shared_network->group->allow_bootp)) {
note("Ignoring BOOTP request from client %s via %s",
print_hw_addr(packet->raw->htype,
packet->raw->hlen, packet->raw->chaddr),
packet->raw->giaddr.s_addr ?
inet_ntoa(packet->raw->giaddr) :
packet->interface->name);
return;
}
/*
* If the packet is from a host we don't know and there are no
* dynamic bootp addresses on the network it came in on, drop
* it on the floor.
*/
if (!(packet->shared_network->group->dynamic_bootp)) {
lose:
note("No applicable record for BOOTP host %s via %s",
print_hw_addr(packet->raw->htype,
packet->raw->hlen, packet->raw->chaddr),
packet->raw->giaddr.s_addr ?
inet_ntoa(packet->raw->giaddr) :
packet->interface->name);
return;
}
/*
* If a lease has already been assigned to this client and it's
* still okay to use dynamic bootp on that lease, reassign it.
*/
if (lease) {
/*
* If this lease can be used for dynamic bootp, do so.
*/
if ((lease->flags & DYNAMIC_BOOTP_OK)) {
/*
* If it's not a DYNAMIC_BOOTP lease, release it
* before reassigning it so that we don't get a
* lease conflict.
*/
if (!(lease->flags & BOOTP_LEASE))
release_lease(lease);
lease->host = host;
ack_lease(packet, lease, 0, 0);
return;
}
/*
* If dynamic BOOTP is no longer allowed for this
* lease, set it free.
*/
release_lease(lease);
}
/*
* If there are dynamic bootp addresses that might be
* available, try to snag one.
*/
for (lease = packet->shared_network->last_lease;
lease && lease->ends <= cur_time;
lease = lease->prev) {
if ((lease->flags & DYNAMIC_BOOTP_OK)) {
lease->host = host;
ack_lease(packet, lease, 0, 0);
return;
}
}
goto lose;
}
/* Make sure we're allowed to boot this client. */
if (hp && (!hp->group->allow_booting)) {
note("Ignoring excluded BOOTP client %s", hp->name);
return;
}
/* Make sure we're allowed to boot this client with bootp. */
if (hp && (!hp->group->allow_bootp)) {
note("Ignoring BOOTP request from client %s", hp->name);
return;
}
/* Set up the outgoing packet... */
memset(&outgoing, 0, sizeof outgoing);
memset(&raw, 0, sizeof raw);
outgoing.raw = &raw;
/*
* If we didn't get a known vendor magic number on the way in, just
* copy the input options to the output.
*/
if (!packet->options_valid && !subnet->group->always_reply_rfc1048 &&
(!hp || !hp->group->always_reply_rfc1048)) {
memcpy(outgoing.raw->options, packet->raw->options,
DHCP_OPTION_LEN);
outgoing.packet_length = BOOTP_MIN_LEN;
} else {
struct tree_cache netmask_tree; /* -- RBF */
/*
* Come up with a list of options that we want to send to this
* client. Start with the per-subnet options, and then override
* those with client-specific options.
*/
memcpy(options, subnet->group->options, sizeof(options));
for (i = 0; i < 256; i++)
if (hp->group->options[i])
options[i] = hp->group->options[i];
/*
* Use the subnet mask from the subnet declaration if no other
* mask has been provided.
*/
if (!options[DHO_SUBNET_MASK]) {
options[DHO_SUBNET_MASK] = &netmask_tree;
netmask_tree.flags = TC_TEMPORARY;
netmask_tree.value = lease->subnet->netmask.iabuf;
netmask_tree.len = lease->subnet->netmask.len;
netmask_tree.buf_size = lease->subnet->netmask.len;
netmask_tree.timeout = -1;
netmask_tree.tree = NULL;
}
/*
* Pack the options into the buffer. Unlike DHCP, we can't pack
* options into the filename and server name buffers.
*/
outgoing.packet_length = cons_options(packet, outgoing.raw,
0, options, 0, 0, 1, NULL, 0);
if (outgoing.packet_length < BOOTP_MIN_LEN)
outgoing.packet_length = BOOTP_MIN_LEN;
}
/* Take the fields that we care about... */
raw.op = BOOTREPLY;
raw.htype = packet->raw->htype;
raw.hlen = packet->raw->hlen;
memcpy(raw.chaddr, packet->raw->chaddr, sizeof(raw.chaddr));
raw.hops = packet->raw->hops;
raw.xid = packet->raw->xid;
raw.secs = packet->raw->secs;
raw.flags = packet->raw->flags;
raw.ciaddr = packet->raw->ciaddr;
memcpy(&raw.yiaddr, ip_address.iabuf, sizeof(raw.yiaddr));
/* Figure out the address of the next server. */
if (hp && hp->group->next_server.len)
memcpy(&raw.siaddr, hp->group->next_server.iabuf, 4);
else if (subnet->group->next_server.len)
memcpy(&raw.siaddr, subnet->group->next_server.iabuf, 4);
else if (subnet->interface_address.len)
memcpy(&raw.siaddr, subnet->interface_address.iabuf, 4);
else
raw.siaddr = packet->interface->primary_address;
raw.giaddr = packet->raw->giaddr;
if (hp->group->server_name)
strncpy(raw.sname, hp->group->server_name, sizeof(raw.sname));
else if (subnet->group->server_name)
strncpy(raw.sname, subnet->group->server_name,
sizeof(raw.sname));
if (hp->group->filename)
strncpy(raw.file, hp->group->filename, sizeof(raw.file));
else if (subnet->group->filename)
strncpy(raw.file, subnet->group->filename, sizeof(raw.file));
else
memcpy(raw.file, packet->raw->file, sizeof(raw.file));
from = packet->interface->primary_address;
/* Report what we're doing... */
note("BOOTREPLY for %s to %s (%s) via %s", piaddr(ip_address),
hp->name, print_hw_addr(packet->raw->htype, packet->raw->hlen,
packet->raw->chaddr), packet->raw->giaddr.s_addr ?
inet_ntoa(packet->raw->giaddr) : packet->interface->name);
/* Set up the parts of the address that are in common. */
memset(&to, 0, sizeof(to));
to.sin_family = AF_INET;
#ifdef HAVE_SA_LEN
to.sin_len = sizeof(to);
#endif
/* If this was gatewayed, send it back to the gateway... */
if (raw.giaddr.s_addr) {
to.sin_addr = raw.giaddr;
to.sin_port = server_port;
(void) send_packet(packet->interface, &raw,
outgoing.packet_length, from, &to, packet->haddr);
return;
}
/*
* If it comes from a client that already knows its address and is not
* requesting a broadcast response, and we can unicast to a client
* without using the ARP protocol, sent it directly to that client.
*/
else if (!(raw.flags & htons(BOOTP_BROADCAST))) {
to.sin_addr = raw.yiaddr;
to.sin_port = client_port;
} else {
/* Otherwise, broadcast it on the local network. */
to.sin_addr.s_addr = INADDR_BROADCAST;
to.sin_port = client_port; /* XXX */
}
errno = 0;
(void) send_packet(packet->interface, &raw,
outgoing.packet_length, from, &to, packet->haddr);
}
void
do_packet(int len, unsigned int from_port, struct iaddr from,
struct hardware *hfrom)
{
struct dhcp_packet *packet = &client->packet;
struct option_data options[256];
struct iaddrlist *ap;
void (*handler)(struct iaddr, struct option_data *);
char *type;
int i, options_valid = 1;
if (packet->hlen > sizeof(packet->chaddr)) {
note("Discarding packet with invalid hlen.");
return;
}
/*
* Silently drop the packet if the client hardware address in the
* packet is not the hardware address of the interface being managed.
*/
if ((ifi->hw_address.hlen != packet->hlen) ||
(memcmp(ifi->hw_address.haddr, packet->chaddr, packet->hlen)))
return;
memset(options, 0, sizeof(options));
if (memcmp(&packet->options, DHCP_OPTIONS_COOKIE, 4) == 0) {
/* Parse the BOOTP/DHCP options field. */
options_valid = parse_option_buffer(options,
&packet->options[4], sizeof(packet->options) - 4);
/* Only DHCP packets have overload areas for options. */
if (options_valid &&
options[DHO_DHCP_MESSAGE_TYPE].data &&
options[DHO_DHCP_OPTION_OVERLOAD].data) {
if (options[DHO_DHCP_OPTION_OVERLOAD].data[0] & 1)
options_valid = parse_option_buffer(options,
(unsigned char *)packet->file,
sizeof(packet->file));
if (options_valid &&
options[DHO_DHCP_OPTION_OVERLOAD].data[0] & 2)
options_valid = parse_option_buffer(options,
(unsigned char *)packet->sname,
sizeof(packet->sname));
}
}
type = "";
handler = NULL;
if (options[DHO_DHCP_MESSAGE_TYPE].data) {
/* Always try a DHCP packet, even if a bad option was seen. */
switch (options[DHO_DHCP_MESSAGE_TYPE].data[0]) {
case DHCPOFFER:
handler = dhcpoffer;
type = "DHCPOFFER";
break;
case DHCPNAK:
handler = dhcpnak;
type = "DHCPNACK";
break;
case DHCPACK:
handler = dhcpack;
type = "DHCPACK";
break;
default:
break;
}
} else if (options_valid && packet->op == BOOTREPLY) {
handler = dhcpoffer;
type = "BOOTREPLY";
}
for (ap = config->reject_list; ap && handler; ap = ap->next)
if (addr_eq(from, ap->addr)) {
note("%s from %s rejected.", type, piaddr(from));
handler = NULL;
}
if (handler)
(*handler)(from, options);
for (i = 0; i < 256; i++)
if (options[i].len && options[i].data)
free(options[i].data);
}