/* dhcp.c DHCP Protocol engine. */ /* * Copyright (c) 2004-2006 by Internet Systems Consortium, Inc. ("ISC") * Copyright (c) 1995-2003 by Internet Software Consortium * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. * * Internet Systems Consortium, Inc. * 950 Charter Street * Redwood City, CA 94063 * * http://www.isc.org/ * * This software has been written for Internet Systems Consortium * by Ted Lemon in cooperation with Vixie Enterprises and Nominum, Inc. * To learn more about Internet Systems 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: dhcp.c,v 1.192.2.63 2006/06/15 17:53:51 dhankins Exp $ Copyright (c) 2004-2006 Internet Systems Consortium. All rights reserved.\n"; #endif /* not lint */ #include "dhcpd.h" int outstanding_pings; static char dhcp_message [256]; static const char *dhcp_type_names [] = { "DHCPDISCOVER", "DHCPOFFER", "DHCPREQUEST", "DHCPDECLINE", "DHCPACK", "DHCPNAK", "DHCPRELEASE", "DHCPINFORM" }; const int dhcp_type_name_max = ((sizeof dhcp_type_names) / sizeof (char *)); #if defined (TRACING) # define send_packet trace_packet_send #endif void dhcp (packet) struct packet *packet; { int ms_nulltp = 0; struct option_cache *oc; struct lease *lease = (struct lease *)0; const char *errmsg; struct data_string data; if (!locate_network (packet) && packet -> packet_type != DHCPREQUEST && packet -> packet_type != DHCPINFORM) { const char *s; char typebuf [32]; errmsg = "unknown network segment"; bad_packet: if (packet -> packet_type > 0 && packet -> packet_type < dhcp_type_name_max - 1) { s = dhcp_type_names [packet -> packet_type - 1]; } else { /* %Audit% Cannot exceed 28 bytes. %2004.06.17,Safe% */ sprintf (typebuf, "type %d", packet -> packet_type); s = typebuf; } log_info ("%s from %s via %s: %s", s, (packet -> raw -> htype ? 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, errmsg); goto out; } /* There is a problem with the relay agent information option, which is that in order for a normal relay agent to append this option, the relay agent has to have been involved in getting the packet from the client to the server. Note that this is the software entity known as the relay agent, _not_ the hardware entity known as a router in which the relay agent may be running, so the fact that a router has forwarded a packet does not mean that the relay agent in the router was involved. So when the client is in INIT or INIT-REBOOT or REBINDING state, the relay agent gets to tack on its options, but when it's not, the relay agent doesn't get to do this, which means that any decisions the DHCP server may make based on the agent options will be made incorrectly. We work around this in the following way: if this is a DHCPREQUEST and doesn't have relay agent information options, we see if there's an existing lease for this IP address and this client that _does_ have stashed agent options. If so, then we tack those options onto the packet as if they came from the client. Later on, when we are deciding whether to steal the agent options from the packet, if the agent options stashed on the lease are the same as those stashed on the packet, we don't steal them - this ensures that the client never receives its agent options. */ if (packet -> packet_type == DHCPREQUEST && packet -> raw -> ciaddr.s_addr && !packet -> raw -> giaddr.s_addr && (packet -> options -> universe_count < agent_universe.index || !packet -> options -> universes [agent_universe.index])) { struct iaddr cip; cip.len = sizeof packet -> raw -> ciaddr; memcpy (cip.iabuf, &packet -> raw -> ciaddr, sizeof packet -> raw -> ciaddr); if (!find_lease_by_ip_addr (&lease, cip, MDL)) goto nolease; /* If there are no agent options on the lease, it's not interesting. */ if (!lease -> agent_options) goto nolease; /* The client should not be unicasting a renewal if its lease has expired, so make it go through the process of getting its agent options legally. */ if (lease -> ends < cur_time) goto nolease; if (lease -> uid_len) { oc = lookup_option (&dhcp_universe, packet -> options, DHO_DHCP_CLIENT_IDENTIFIER); if (!oc) goto nolease; memset (&data, 0, sizeof data); if (!evaluate_option_cache (&data, packet, (struct lease *)0, (struct client_state *)0, packet -> options, (struct option_state *)0, &global_scope, oc, MDL)) goto nolease; if (lease -> uid_len != data.len || memcmp (lease -> uid, data.data, data.len)) { data_string_forget (&data, MDL); goto nolease; } data_string_forget (&data, MDL); } else if ((lease -> hardware_addr.hbuf [0] != packet -> raw -> htype) || (lease -> hardware_addr.hlen - 1 != packet -> raw -> hlen) || memcmp (&lease -> hardware_addr.hbuf [1], packet -> raw -> chaddr, packet -> raw -> hlen)) goto nolease; /* Okay, so we found a lease that matches the client. */ option_chain_head_reference ((struct option_chain_head **) &(packet -> options -> universes [agent_universe.index]), lease -> agent_options, MDL); } nolease: /* If a client null terminates options it sends, it probably * expects the server to reciprocate. */ if ((oc = lookup_option (&dhcp_universe, packet -> options, DHO_HOST_NAME))) { if (!oc -> expression) ms_nulltp = oc->flags & OPTION_HAD_NULLS; } /* Classify the client. */ classify_client (packet); switch (packet -> packet_type) { case DHCPDISCOVER: dhcpdiscover (packet, ms_nulltp); break; case DHCPREQUEST: dhcprequest (packet, ms_nulltp, lease); break; case DHCPRELEASE: dhcprelease (packet, ms_nulltp); break; case DHCPDECLINE: dhcpdecline (packet, ms_nulltp); break; case DHCPINFORM: dhcpinform (packet, ms_nulltp); break; case DHCPACK: case DHCPOFFER: case DHCPNAK: break; default: errmsg = "unknown packet type"; goto bad_packet; } out: if (lease) lease_dereference (&lease, MDL); } void dhcpdiscover (packet, ms_nulltp) struct packet *packet; int ms_nulltp; { struct lease *lease = (struct lease *)0; char msgbuf [1024]; /* XXX */ TIME when; const char *s; int peer_has_leases = 0; #if defined (FAILOVER_PROTOCOL) dhcp_failover_state_t *peer; #endif find_lease (&lease, packet, packet -> shared_network, 0, &peer_has_leases, (struct lease *)0, MDL); if (lease && lease -> client_hostname) { if ((strlen (lease -> client_hostname) <= 64) && db_printable (lease -> client_hostname)) s = lease -> client_hostname; else s = "Hostname Unsuitable for Printing"; } else s = (char *)0; /* %Audit% This is log output. %2004.06.17,Safe% * If we truncate we hope the user can get a hint from the log. */ snprintf (msgbuf, sizeof msgbuf, "DHCPDISCOVER from %s %s%s%svia %s", (packet -> raw -> htype ? print_hw_addr (packet -> raw -> htype, packet -> raw -> hlen, packet -> raw -> chaddr) : (lease ? print_hex_1 (lease -> uid_len, lease -> uid, lease -> uid_len) : "")), s ? "(" : "", s ? s : "", s ? ") " : "", packet -> raw -> giaddr.s_addr ? inet_ntoa (packet -> raw -> giaddr) : packet -> interface -> name); /* Sourceless packets don't make sense here. */ if (!packet -> shared_network) { log_info ("Packet from unknown subnet: %s", inet_ntoa (packet -> raw -> giaddr)); goto out; } #if defined (FAILOVER_PROTOCOL) if (lease && lease -> pool && lease -> pool -> failover_peer) { peer = lease -> pool -> failover_peer; /* If the lease is ours to allocate, then allocate it. */ if (lease_mine_to_reallocate(lease)) { if (lease->pool && lease->pool->failover_peer) dhcp_failover_pool_check(lease->pool); /* If the lease is active, it belongs to the client. This * is the right lease, if we are to offer one. We decide * wether or not to offer later on. */ } else if (lease->binding_state == FTS_ACTIVE) { ; /* This space intentionally left blank. */ /* Otherwise, we can't let the client have this lease. */ } else { #if defined (DEBUG_FIND_LEASE) log_debug ("discarding %s - %s", piaddr (lease -> ip_addr), binding_state_print (lease -> binding_state)); #endif lease_dereference (&lease, MDL); } } #endif /* If we didn't find a lease, try to allocate one... */ if (!lease) { if (!allocate_lease (&lease, packet, packet -> shared_network -> pools, &peer_has_leases)) { if (peer_has_leases) log_error ("%s: peer holds all free leases", msgbuf); else log_error ("%s: network %s: no free leases", msgbuf, packet -> shared_network -> name); return; } #if defined (FAILOVER_PROTOCOL) if (lease -> pool && lease -> pool -> failover_peer) dhcp_failover_pool_check (lease -> pool); #endif } #if defined (FAILOVER_PROTOCOL) if (lease && lease -> pool && lease -> pool -> failover_peer) { peer = lease -> pool -> failover_peer; if (peer -> service_state == not_responding || peer -> service_state == service_startup) { log_info ("%s: not responding%s", msgbuf, peer -> nrr); goto out; } } else peer = (dhcp_failover_state_t *)0; /* Do load balancing if configured. */ if (peer && (peer -> service_state == cooperating) && !load_balance_mine (packet, peer)) { if (peer_has_leases) { log_debug ("%s: load balance to peer %s", msgbuf, peer -> name); goto out; } else { log_debug ("%s: cancel load balance to peer %s - %s", msgbuf, peer -> name, "no free leases"); } } #endif /* If it's an expired lease, get rid of any bindings. */ if (lease -> ends < cur_time && lease -> scope) binding_scope_dereference (&lease -> scope, MDL); /* Set the lease to really expire in 2 minutes, unless it has not yet expired, in which case leave its expiry time alone. */ when = cur_time + 120; if (when < lease -> ends) when = lease -> ends; ack_lease (packet, lease, DHCPOFFER, when, msgbuf, ms_nulltp, (struct host_decl *)0); out: if (lease) lease_dereference (&lease, MDL); } void dhcprequest (packet, ms_nulltp, ip_lease) struct packet *packet; int ms_nulltp; struct lease *ip_lease; { struct lease *lease; struct iaddr cip; struct iaddr sip; struct subnet *subnet; int ours = 0; struct option_cache *oc; struct data_string data; int status; char msgbuf [1024]; /* XXX */ const char *s; char smbuf [19]; #if defined (FAILOVER_PROTOCOL) dhcp_failover_state_t *peer; #endif int have_server_identifier = 0; int have_requested_addr = 0; oc = lookup_option (&dhcp_universe, packet -> options, DHO_DHCP_REQUESTED_ADDRESS); memset (&data, 0, sizeof data); if (oc && evaluate_option_cache (&data, packet, (struct lease *)0, (struct client_state *)0, packet -> options, (struct option_state *)0, &global_scope, oc, MDL)) { cip.len = 4; memcpy (cip.iabuf, data.data, 4); data_string_forget (&data, MDL); have_requested_addr = 1; } else { oc = (struct option_cache *)0; cip.len = 4; memcpy (cip.iabuf, &packet -> raw -> ciaddr.s_addr, 4); } /* Find the lease that matches the address requested by the client. */ subnet = (struct subnet *)0; lease = (struct lease *)0; if (find_subnet (&subnet, cip, MDL)) find_lease (&lease, packet, subnet -> shared_network, &ours, 0, ip_lease, MDL); if (lease && lease -> client_hostname) { if ((strlen (lease -> client_hostname) <= 64) && db_printable (lease -> client_hostname)) s = lease -> client_hostname; else s = "Hostname Unsuitable for Printing"; } else s = (char *)0; oc = lookup_option (&dhcp_universe, packet -> options, DHO_DHCP_SERVER_IDENTIFIER); memset (&data, 0, sizeof data); if (oc && evaluate_option_cache (&data, packet, (struct lease *)0, (struct client_state *)0, packet -> options, (struct option_state *)0, &global_scope, oc, MDL)) { sip.len = 4; memcpy (sip.iabuf, data.data, 4); data_string_forget (&data, MDL); /* piaddr() should not return more than a 15 byte string. * safe. */ sprintf (smbuf, " (%s)", piaddr (sip)); have_server_identifier = 1; } else smbuf [0] = 0; /* %Audit% This is log output. %2004.06.17,Safe% * If we truncate we hope the user can get a hint from the log. */ snprintf (msgbuf, sizeof msgbuf, "DHCPREQUEST for %s%s from %s %s%s%svia %s", piaddr (cip), smbuf, (packet -> raw -> htype ? print_hw_addr (packet -> raw -> htype, packet -> raw -> hlen, packet -> raw -> chaddr) : (lease ? print_hex_1 (lease -> uid_len, lease -> uid, lease -> uid_len) : "")), s ? "(" : "", s ? s : "", s ? ") " : "", packet -> raw -> giaddr.s_addr ? inet_ntoa (packet -> raw -> giaddr) : packet -> interface -> name); #if defined (FAILOVER_PROTOCOL) if (lease && lease -> pool && lease -> pool -> failover_peer) { peer = lease -> pool -> failover_peer; if (peer -> service_state == not_responding || peer -> service_state == service_startup) { log_info ("%s: not responding%s", msgbuf, peer -> nrr); goto out; } /* "load balance to peer" - is not done at all for request. * * If it's RENEWING, we are the only server to hear it, so * we have to serve it. If it's REBINDING, it's out of * communication with the other server, so there's no point * in waiting to serve it. However, if the lease we're * offering is not a free lease, then we may be the only * server that can offer it, so we can't load balance if * the lease isn't in the free or backup state. If it is * in the free or backup state, then that state is what * mandates one server or the other should perform the * allocation, not the LBA...we know the peer cannot * allocate a request for an address in our free state. * * So our only compass is lease_mine_to_reallocate(). This * effects both load balancing, and a sanity-check that we * are not going to try to allocate a lease that isn't ours. */ if ((lease -> binding_state == FTS_FREE || lease -> binding_state == FTS_BACKUP) && !lease_mine_to_reallocate (lease)) { log_debug ("%s: lease owned by peer", msgbuf); goto out; } /* If the lease is in a transitional state, we can't renew it. */ if ((lease -> binding_state == FTS_RELEASED || lease -> binding_state == FTS_EXPIRED) && !lease_mine_to_reallocate (lease)) { log_debug ("%s: lease in transition state %s", msgbuf, lease -> binding_state == FTS_RELEASED ? "released" : "expired"); goto out; } /* It's actually very unlikely that we'll ever get here, but if we do, tell the client to stop using the lease, because the administrator reset it. */ if (lease -> binding_state == FTS_RESET && !lease_mine_to_reallocate (lease)) { log_debug ("%s: lease reset by administrator", msgbuf); nak_lease (packet, &cip); goto out; } /* At this point it's possible that we will get a broadcast DHCPREQUEST for a lease that we didn't offer, because both we and the peer are in a position to offer it. In that case, we probably shouldn't answer. In order to not answer, we would have to compare the server identifier sent by the client with the list of possible server identifiers we can send, and if the client's identifier isn't on the list, drop the DHCPREQUEST. We aren't currently doing that for two reasons - first, it's not clear that all clients do the right thing with respect to sending the client identifier, which could mean that we might simply not respond to a client that is depending on us to respond. Secondly, we allow the user to specify the server identifier to send, and we don't enforce that the server identifier should be one of our IP addresses. This is probably not a big deal, but it's theoretically an issue. The reason we care about this is that if both servers send a DHCPACK to the DHCPREQUEST, they are then going to send dueling BNDUPD messages, which could cause trouble. I think it causes no harm, but it seems wrong. */ } else peer = (dhcp_failover_state_t *)0; #endif /* If a client on a given network REQUESTs a lease on an address on a different network, NAK it. If the Requested Address option was used, the protocol says that it must have been broadcast, so we can trust the source network information. If ciaddr was specified and Requested Address was not, then we really only know for sure what network a packet came from if it came through a BOOTP gateway - if it came through an IP router, we'll just have to assume that it's cool. If we don't think we know where the packet came from, it came through a gateway from an unknown network, so it's not from a RENEWING client. If we recognize the network it *thinks* it's on, we can NAK it even though we don't recognize the network it's *actually* on; otherwise we just have to ignore it. We don't currently try to take advantage of access to the raw packet, because it's not available on all platforms. So a packet that was unicast to us through a router from a RENEWING client is going to look exactly like a packet that was broadcast to us from an INIT-REBOOT client. Since we can't tell the difference between these two kinds of packets, if the packet appears to have come in off the local wire, we have to treat it as if it's a RENEWING client. This means that we can't NAK a RENEWING client on the local wire that has a bogus address. The good news is that we won't ACK it either, so it should revert to INIT state and send us a DHCPDISCOVER, which we *can* work with. Because we can't detect that a RENEWING client is on the wrong wire, it's going to sit there trying to renew until it gets to the REBIND state, when we *can* NAK it because the packet will get to us through a BOOTP gateway. We shouldn't actually see DHCPREQUEST packets from RENEWING clients on the wrong wire anyway, since their idea of their local router will be wrong. In any case, the protocol doesn't really allow us to NAK a DHCPREQUEST from a RENEWING client, so we can punt on this issue. */ if (!packet -> shared_network || (packet -> raw -> ciaddr.s_addr && packet -> raw -> giaddr.s_addr) || (have_requested_addr && !packet -> raw -> ciaddr.s_addr)) { /* If we don't know where it came from but we do know where it claims to have come from, it didn't come from there. */ if (!packet -> shared_network) { if (subnet && subnet -> group -> authoritative) { log_info ("%s: wrong network.", msgbuf); nak_lease (packet, &cip); goto out; } /* Otherwise, ignore it. */ log_info ("%s: ignored (%s).", msgbuf, (subnet ? "not authoritative" : "unknown subnet")); goto out; } /* If we do know where it came from and it asked for an address that is not on that shared network, nak it. */ if (subnet) subnet_dereference (&subnet, MDL); if (!find_grouped_subnet (&subnet, packet -> shared_network, cip, MDL)) { if (packet -> shared_network -> group -> authoritative) { log_info ("%s: wrong network.", msgbuf); nak_lease (packet, &cip); goto out; } log_info ("%s: ignored (not authoritative).", msgbuf); return; } } /* If the address the client asked for is ours, but it wasn't available for the client, NAK it. */ if (!lease && ours) { log_info ("%s: lease %s unavailable.", msgbuf, piaddr (cip)); nak_lease (packet, &cip); goto out; } /* Otherwise, send the lease to the client if we found one. */ if (lease) { ack_lease (packet, lease, DHCPACK, 0, msgbuf, ms_nulltp, (struct host_decl *)0); } else log_info ("%s: unknown lease %s.", msgbuf, piaddr (cip)); out: if (subnet) subnet_dereference (&subnet, MDL); if (lease) lease_dereference (&lease, MDL); return; } void dhcprelease (packet, ms_nulltp) struct packet *packet; int ms_nulltp; { struct lease *lease = (struct lease *)0, *next = (struct lease *)0; struct iaddr cip; struct option_cache *oc; struct data_string data; const char *s; char msgbuf [1024], cstr[16]; /* XXX */ /* DHCPRELEASE must not specify address in requested-address option, but old protocol specs weren't explicit about this, so let it go. */ if ((oc = lookup_option (&dhcp_universe, packet -> options, DHO_DHCP_REQUESTED_ADDRESS))) { log_info ("DHCPRELEASE from %s specified requested-address.", print_hw_addr (packet -> raw -> htype, packet -> raw -> hlen, packet -> raw -> chaddr)); } oc = lookup_option (&dhcp_universe, packet -> options, DHO_DHCP_CLIENT_IDENTIFIER); memset (&data, 0, sizeof data); if (oc && evaluate_option_cache (&data, packet, (struct lease *)0, (struct client_state *)0, packet -> options, (struct option_state *)0, &global_scope, oc, MDL)) { find_lease_by_uid (&lease, data.data, data.len, MDL); data_string_forget (&data, MDL); /* See if we can find a lease that matches the IP address the client is claiming. */ while (lease) { if (lease -> n_uid) lease_reference (&next, lease -> n_uid, MDL); if (!memcmp (&packet -> raw -> ciaddr, lease -> ip_addr.iabuf, 4)) { break; } lease_dereference (&lease, MDL); if (next) { lease_reference (&lease, next, MDL); lease_dereference (&next, MDL); } } if (next) lease_dereference (&next, MDL); } /* The client is supposed to pass a valid client-identifier, but the spec on this has changed historically, so try the IP address in ciaddr if the client-identifier fails. */ if (!lease) { cip.len = 4; memcpy (cip.iabuf, &packet -> raw -> ciaddr, 4); find_lease_by_ip_addr (&lease, cip, MDL); } /* If the hardware address doesn't match, don't do the release. */ if (lease && (lease -> hardware_addr.hlen != packet -> raw -> hlen + 1 || lease -> hardware_addr.hbuf [0] != packet -> raw -> htype || memcmp (&lease -> hardware_addr.hbuf [1], packet -> raw -> chaddr, packet -> raw -> hlen))) lease_dereference (&lease, MDL); if (lease && lease -> client_hostname) { if ((strlen (lease -> client_hostname) <= 64) && db_printable (lease -> client_hostname)) s = lease -> client_hostname; else s = "Hostname Unsuitable for Printing"; } else s = (char *)0; /* %Audit% Cannot exceed 16 bytes. %2004.06.17,Safe% * We copy this out to stack because we actually want to log two * inet_ntoa()'s in this message. */ strncpy(cstr, inet_ntoa (packet -> raw -> ciaddr), 15); cstr[15] = '\0'; /* %Audit% This is log output. %2004.06.17,Safe% * If we truncate we hope the user can get a hint from the log. */ snprintf (msgbuf, sizeof msgbuf, "DHCPRELEASE of %s from %s %s%s%svia %s (%sfound)", cstr, (packet -> raw -> htype ? print_hw_addr (packet -> raw -> htype, packet -> raw -> hlen, packet -> raw -> chaddr) : (lease ? print_hex_1 (lease -> uid_len, lease -> uid, lease -> uid_len) : "")), s ? "(" : "", s ? s : "", s ? ") " : "", packet -> raw -> giaddr.s_addr ? inet_ntoa (packet -> raw -> giaddr) : packet -> interface -> name, lease ? "" : "not "); #if defined (FAILOVER_PROTOCOL) if (lease && lease -> pool && lease -> pool -> failover_peer) { dhcp_failover_state_t *peer = lease -> pool -> failover_peer; if (peer -> service_state == not_responding || peer -> service_state == service_startup) { log_info ("%s: ignored%s", peer -> name, peer -> nrr); goto out; } /* DHCPRELEASE messages are unicast, so if the client sent the DHCPRELEASE to us, it's not going to send it to the peer. Not sure why this would happen, and if it does happen I think we still have to change the lease state, so that's what we're doing. XXX See what it says in the draft about this. */ } #endif /* If we found a lease, release it. */ if (lease && lease -> ends > cur_time) { release_lease (lease, packet); } log_info ("%s", msgbuf); out: if (lease) lease_dereference (&lease, MDL); } void dhcpdecline (packet, ms_nulltp) struct packet *packet; int ms_nulltp; { struct lease *lease = (struct lease *)0; struct option_state *options = (struct option_state *)0; int ignorep = 0; int i; const char *status; const char *s; char msgbuf [1024]; /* XXX */ struct iaddr cip; struct option_cache *oc; struct data_string data; /* DHCPDECLINE must specify address. */ if (!(oc = lookup_option (&dhcp_universe, packet -> options, DHO_DHCP_REQUESTED_ADDRESS))) return; memset (&data, 0, sizeof data); if (!evaluate_option_cache (&data, packet, (struct lease *)0, (struct client_state *)0, packet -> options, (struct option_state *)0, &global_scope, oc, MDL)) return; cip.len = 4; memcpy (cip.iabuf, data.data, 4); data_string_forget (&data, MDL); find_lease_by_ip_addr (&lease, cip, MDL); if (lease && lease -> client_hostname) { if ((strlen (lease -> client_hostname) <= 64) && db_printable (lease -> client_hostname)) s = lease -> client_hostname; else s = "Hostname Unsuitable for Printing"; } else s = (char *)0; /* %Audit% This is log output. %2004.06.17,Safe% * If we truncate we hope the user can get a hint from the log. */ snprintf (msgbuf, sizeof msgbuf, "DHCPDECLINE of %s from %s %s%s%svia %s", piaddr (cip), (packet -> raw -> htype ? print_hw_addr (packet -> raw -> htype, packet -> raw -> hlen, packet -> raw -> chaddr) : (lease ? print_hex_1 (lease -> uid_len, lease -> uid, lease -> uid_len) : "")), s ? "(" : "", s ? s : "", s ? ") " : "", packet -> raw -> giaddr.s_addr ? inet_ntoa (packet -> raw -> giaddr) : packet -> interface -> name); option_state_allocate (&options, MDL); /* Execute statements in scope starting with the subnet scope. */ if (lease) execute_statements_in_scope ((struct binding_value **)0, packet, (struct lease *)0, (struct client_state *)0, packet -> options, options, &global_scope, lease -> subnet -> group, (struct group *)0); /* Execute statements in the class scopes. */ for (i = packet -> class_count; i > 0; i--) { execute_statements_in_scope ((struct binding_value **)0, packet, (struct lease *)0, (struct client_state *)0, packet -> options, options, &global_scope, packet -> classes [i - 1] -> group, lease ? lease -> subnet -> group : (struct group *)0); } /* Drop the request if dhcpdeclines are being ignored. */ oc = lookup_option (&server_universe, options, SV_DECLINES); if (!oc || evaluate_boolean_option_cache (&ignorep, packet, lease, (struct client_state *)0, packet -> options, options, &lease -> scope, oc, MDL)) { /* If we found a lease, mark it as unusable and complain. */ if (lease) { #if defined (FAILOVER_PROTOCOL) if (lease -> pool && lease -> pool -> failover_peer) { dhcp_failover_state_t *peer = lease -> pool -> failover_peer; if (peer -> service_state == not_responding || peer -> service_state == service_startup) { if (!ignorep) log_info ("%s: ignored%s", peer -> name, peer -> nrr); goto out; } /* DHCPDECLINE messages are broadcast, so we can safely ignore the DHCPDECLINE if the peer has the lease. XXX Of course, at this point that information has been lost. */ } #endif abandon_lease (lease, "declined."); status = "abandoned"; } status = "not found"; } else status = "ignored"; if (!ignorep) log_info ("%s: %s", msgbuf, status); out: if (options) option_state_dereference (&options, MDL); if (lease) lease_dereference (&lease, MDL); } void dhcpinform (packet, ms_nulltp) struct packet *packet; int ms_nulltp; { char msgbuf [1024]; struct data_string d1, prl; struct option_cache *oc; struct expression *expr; struct option_state *options = (struct option_state *)0; struct dhcp_packet raw; struct packet outgoing; unsigned char dhcpack = DHCPACK; struct subnet *subnet = (struct subnet *)0; struct iaddr cip, gip; unsigned i, j; int nulltp; struct sockaddr_in to; struct in_addr from; /* The client should set ciaddr to its IP address, but apparently it's common for clients not to do this, so we'll use their IP source address if they didn't set ciaddr. */ if (!packet -> raw -> ciaddr.s_addr) { cip.len = 4; memcpy (cip.iabuf, &packet -> client_addr.iabuf, 4); } else { cip.len = 4; memcpy (cip.iabuf, &packet -> raw -> ciaddr, 4); } if (packet->raw->giaddr.s_addr) { gip.len = 4; memcpy(gip.iabuf, &packet->raw->giaddr, 4); } else gip.len = 0; /* %Audit% This is log output. %2004.06.17,Safe% * If we truncate we hope the user can get a hint from the log. */ snprintf (msgbuf, sizeof msgbuf, "DHCPINFORM from %s via %s", piaddr (cip), packet->raw->giaddr.s_addr ? inet_ntoa(packet->raw->giaddr) : packet -> interface -> name); /* If the IP source address is zero, don't respond. */ if (!memcmp (cip.iabuf, "\0\0\0", 4)) { log_info ("%s: ignored (null source address).", msgbuf); return; } /* Find the subnet that the client is on. */ if (gip.len) { /* XXX - do subnet selection relay agent suboption here */ find_subnet(&subnet, gip, MDL); } else { /* XXX - do subnet selection (not relay agent) option here */ find_subnet(&subnet, cip, MDL); } /* Sourceless packets don't make sense here. */ if (!subnet) { log_info ("%s: unknown subnet for address %s", msgbuf, gip.len ? piaddr(gip) : piaddr(cip)); return; } /* We don't respond to DHCPINFORM packets if we're not authoritative. It would be nice if a per-host value could override this, but there's overhead involved in checking this, so let's see how people react first. */ if (subnet && !subnet -> group -> authoritative) { static int eso = 0; log_info ("%s: not authoritative for subnet %s", msgbuf, piaddr (subnet -> net)); if (!eso) { log_info ("If this DHCP server is authoritative for%s", " that subnet,"); log_info ("please write an `authoritative;' directi%s", "ve either in the"); log_info ("subnet declaration or in some scope that%s", " encloses the"); log_info ("subnet declaration - for example, write %s", "it at the top"); log_info ("of the dhcpd.conf file."); } if (eso++ == 100) eso = 0; subnet_dereference (&subnet, MDL); return; } option_state_allocate (&options, MDL); memset (&outgoing, 0, sizeof outgoing); memset (&raw, 0, sizeof raw); outgoing.raw = &raw; /* Execute statements in scope starting with the subnet scope. */ if (subnet) execute_statements_in_scope ((struct binding_value **)0, packet, (struct lease *)0, (struct client_state *)0, packet -> options, options, &global_scope, subnet -> group, (struct group *)0); /* Execute statements in the class scopes. */ for (i = packet -> class_count; i > 0; i--) { execute_statements_in_scope ((struct binding_value **)0, packet, (struct lease *)0, (struct client_state *)0, packet -> options, options, &global_scope, packet -> classes [i - 1] -> group, subnet ? subnet -> group : (struct group *)0); } /* Figure out the filename. */ memset (&d1, 0, sizeof d1); oc = lookup_option (&server_universe, options, SV_FILENAME); if (oc && evaluate_option_cache (&d1, packet, (struct lease *)0, (struct client_state *)0, packet -> options, (struct option_state *)0, &global_scope, oc, MDL)) { i = d1.len; if (i > sizeof raw.file) i = sizeof raw.file; else raw.file [i] = 0; memcpy (raw.file, d1.data, i); data_string_forget (&d1, MDL); } /* Choose a server name as above. */ oc = lookup_option (&server_universe, options, SV_SERVER_NAME); if (oc && evaluate_option_cache (&d1, packet, (struct lease *)0, (struct client_state *)0, packet -> options, (struct option_state *)0, &global_scope, oc, MDL)) { i = d1.len; if (i > sizeof raw.sname) i = sizeof raw.sname; else raw.sname [i] = 0; memcpy (raw.sname, d1.data, i); data_string_forget (&d1, MDL); } /* Set a flag if this client is a lame Microsoft client that NUL terminates string options and expects us to do likewise. */ nulltp = 0; if ((oc = lookup_option (&dhcp_universe, packet -> options, DHO_HOST_NAME))) { if (!oc->expression) nulltp = oc->flags & OPTION_HAD_NULLS; } /* Put in DHCP-specific options. */ i = DHO_DHCP_MESSAGE_TYPE; oc = (struct option_cache *)0; if (option_cache_allocate (&oc, MDL)) { if (make_const_data (&oc -> expression, &dhcpack, 1, 0, 0, MDL)) { oc -> option = dhcp_universe.options [i]; save_option (&dhcp_universe, options, oc); } option_cache_dereference (&oc, MDL); } i = DHO_DHCP_SERVER_IDENTIFIER; if (!(oc = lookup_option (&dhcp_universe, options, i))) { use_primary: oc = (struct option_cache *)0; if (option_cache_allocate (&oc, MDL)) { if (make_const_data (&oc -> expression, ((unsigned char *) &packet -> interface -> primary_address), sizeof packet -> interface -> primary_address, 0, 0, MDL)) { oc -> option = dhcp_universe.options [i]; save_option (&dhcp_universe, options, oc); } option_cache_dereference (&oc, MDL); } from = packet -> interface -> primary_address; } else { if (evaluate_option_cache (&d1, packet, (struct lease *)0, (struct client_state *)0, packet -> options, options, &global_scope, oc, MDL)) { if (!d1.len || d1.len != sizeof from) { data_string_forget (&d1, MDL); goto use_primary; } memcpy (&from, d1.data, sizeof from); data_string_forget (&d1, MDL); } else goto use_primary; } /* Use the subnet mask from the subnet declaration if no other mask has been provided. */ i = DHO_SUBNET_MASK; if (subnet && !lookup_option (&dhcp_universe, options, i)) { oc = (struct option_cache *)0; if (option_cache_allocate (&oc, MDL)) { if (make_const_data (&oc -> expression, subnet -> netmask.iabuf, subnet -> netmask.len, 0, 0, MDL)) { oc -> option = dhcp_universe.options [i]; save_option (&dhcp_universe, options, oc); } option_cache_dereference (&oc, MDL); } } /* If a site option space has been specified, use that for site option codes. */ i = SV_SITE_OPTION_SPACE; if ((oc = lookup_option (&server_universe, options, i)) && evaluate_option_cache (&d1, packet, (struct lease *)0, (struct client_state *)0, packet -> options, options, &global_scope, oc, MDL)) { struct universe *u = (struct universe *)0; if (!universe_hash_lookup (&u, universe_hash, (const char *)d1.data, d1.len, MDL)) { log_error ("unknown option space %s.", d1.data); option_state_dereference (&options, MDL); if (subnet) subnet_dereference (&subnet, MDL); return; } options -> site_universe = u -> index; options -> site_code_min = 128; /* XXX */ data_string_forget (&d1, MDL); } else { options -> site_universe = dhcp_universe.index; options -> site_code_min = 0; /* Trust me, it works. */ } memset (&prl, 0, sizeof prl); /* Use the parameter list from the scope if there is one. */ oc = lookup_option (&dhcp_universe, options, DHO_DHCP_PARAMETER_REQUEST_LIST); /* Otherwise, if the client has provided a list of options that it wishes returned, use it to prioritize. Otherwise, prioritize based on the default priority list. */ if (!oc) oc = lookup_option (&dhcp_universe, packet -> options, DHO_DHCP_PARAMETER_REQUEST_LIST); if (oc) evaluate_option_cache (&prl, packet, (struct lease *)0, (struct client_state *)0, packet -> options, options, &global_scope, oc, MDL); #ifdef DEBUG_PACKET dump_packet (packet); dump_raw ((unsigned char *)packet -> raw, packet -> packet_length); #endif log_info ("%s", msgbuf); /* Figure out the address of the boot file server. */ if ((oc = lookup_option (&server_universe, options, SV_NEXT_SERVER))) { if (evaluate_option_cache (&d1, packet, (struct lease *)0, (struct client_state *)0, packet -> options, options, &global_scope, oc, MDL)) { /* If there was more than one answer, take the first. */ if (d1.len >= 4 && d1.data) memcpy (&raw.siaddr, d1.data, 4); data_string_forget (&d1, MDL); } } /* Set up the option buffer... */ outgoing.packet_length = cons_options (packet, outgoing.raw, (struct lease *)0, (struct client_state *)0, 0, packet -> options, options, &global_scope, 0, nulltp, 0, prl.len ? &prl : (struct data_string *)0, (char *)0); option_state_dereference (&options, MDL); data_string_forget (&prl, MDL); /* Make sure that the packet is at least as big as a BOOTP packet. */ if (outgoing.packet_length < BOOTP_MIN_LEN) outgoing.packet_length = BOOTP_MIN_LEN; raw.giaddr = packet -> raw -> giaddr; raw.ciaddr = packet -> raw -> ciaddr; memcpy (raw.chaddr, packet -> raw -> chaddr, sizeof raw.chaddr); raw.hlen = packet -> raw -> hlen; raw.htype = packet -> raw -> htype; raw.xid = packet -> raw -> xid; raw.secs = packet -> raw -> secs; raw.flags = packet -> raw -> flags; raw.hops = packet -> raw -> hops; raw.op = BOOTREPLY; #ifdef DEBUG_PACKET dump_packet (&outgoing); dump_raw ((unsigned char *)&raw, outgoing.packet_length); #endif /* Set up the common stuff... */ to.sin_family = AF_INET; #ifdef HAVE_SA_LEN to.sin_len = sizeof to; #endif memset (to.sin_zero, 0, sizeof to.sin_zero); /* RFC2131 states the server SHOULD unciast to ciaddr. * There are two wrinkles - relays, and when ciaddr is zero. * There's actually no mention of relays at all in rfc2131. * I think it's best to use relays where present...a relay is * a bit more trustworthy about getting the message to a client * than a client might be (it's better to send to a relay than * to, say, a link-local address the client has selected). * * Where ciaddr is zero, which actually does happen quite frequently * even though rfc2131 is unequivocal on the subject, we try to help * by using the IP source address. * * Where ciaddr is zero AND we got it via a relay, the IP source * address is the relay - and we're transmitting to the client * port. This might cause a loop. * * So, overall, this is neater if the relay is selected first, * treated like a relay, client addressing taken second. Since * a relay possibly has no way of knowing how to reach the client * if chaddr is zero (equally as common as ciaddr being zeroed), * set the broadcast bit to try and help. */ if (gip.len) { memcpy(&to.sin_addr, gip.iabuf, 4); to.sin_port = local_port; if (!raw.hlen) raw.flags |= htons(BOOTP_BROADCAST); } else { memcpy(&to.sin_addr, cip.iabuf, 4); to.sin_port = remote_port; } /* Report what we're sending. */ snprintf(msgbuf, sizeof msgbuf, "DHCPACK to %s (%s) via", piaddr(cip), (packet->raw->htype && packet->raw->hlen) ? print_hw_addr(packet->raw->htype, packet->raw->hlen, packet->raw->chaddr) : ""); log_info("%s %s", msgbuf, gip.len ? piaddr(gip) : packet->interface->name); errno = 0; send_packet ((fallback_interface ? fallback_interface : packet -> interface), &outgoing, &raw, outgoing.packet_length, from, &to, (struct hardware *)0); if (subnet) subnet_dereference (&subnet, MDL); } void nak_lease (packet, cip) struct packet *packet; struct iaddr *cip; { struct sockaddr_in to; struct in_addr from; int result; struct dhcp_packet raw; unsigned char nak = DHCPNAK; struct packet outgoing; struct hardware hto; unsigned i; struct data_string data; struct option_state *options = (struct option_state *)0; struct expression *expr; struct option_cache *oc = (struct option_cache *)0; struct iaddr myfrom; option_state_allocate (&options, MDL); memset (&outgoing, 0, sizeof outgoing); memset (&raw, 0, sizeof raw); outgoing.raw = &raw; /* Set DHCP_MESSAGE_TYPE to DHCPNAK */ if (!option_cache_allocate (&oc, MDL)) { log_error ("No memory for DHCPNAK message type."); option_state_dereference (&options, MDL); return; } if (!make_const_data (&oc -> expression, &nak, sizeof nak, 0, 0, MDL)) { log_error ("No memory for expr_const expression."); option_cache_dereference (&oc, MDL); option_state_dereference (&options, MDL); return; } oc -> option = dhcp_universe.options [DHO_DHCP_MESSAGE_TYPE]; save_option (&dhcp_universe, options, oc); option_cache_dereference (&oc, MDL); /* Set DHCP_MESSAGE to whatever the message is */ if (!option_cache_allocate (&oc, MDL)) { log_error ("No memory for DHCPNAK message type."); option_state_dereference (&options, MDL); return; } if (!make_const_data (&oc -> expression, (unsigned char *)dhcp_message, strlen (dhcp_message), 1, 0, MDL)) { log_error ("No memory for expr_const expression."); option_cache_dereference (&oc, MDL); option_state_dereference (&options, MDL); return; } oc -> option = dhcp_universe.options [DHO_DHCP_MESSAGE]; save_option (&dhcp_universe, options, oc); option_cache_dereference (&oc, MDL); i = DHO_DHCP_SERVER_IDENTIFIER; if (!(oc = lookup_option (&dhcp_universe, options, i))) { use_primary: oc = (struct option_cache *)0; if (option_cache_allocate (&oc, MDL)) { if (make_const_data (&oc -> expression, ((unsigned char *) &packet -> interface -> primary_address), sizeof packet -> interface -> primary_address, 0, 0, MDL)) { oc -> option = dhcp_universe.options [i]; save_option (&dhcp_universe, options, oc); } option_cache_dereference (&oc, MDL); } myfrom.len = sizeof packet -> interface -> primary_address; memcpy (myfrom.iabuf, &packet -> interface -> primary_address, myfrom.len); } else { memset (&data, 0, sizeof data); if (evaluate_option_cache (&data, packet, (struct lease *)0, (struct client_state *)0, packet -> options, options, &global_scope, oc, MDL)) { if (!data.len || data.len > sizeof myfrom.iabuf) { data_string_forget (&data, MDL); goto use_primary; } memcpy (myfrom.iabuf, data.data, data.len); myfrom.len = data.len; data_string_forget (&data, MDL); } else goto use_primary; } /* If there were agent options in the incoming packet, return them. */ if (packet -> raw -> giaddr.s_addr && packet -> options -> universe_count > agent_universe.index && packet -> options -> universes [agent_universe.index]) { option_chain_head_reference ((struct option_chain_head **) &(options -> universes [agent_universe.index]), (struct option_chain_head *) packet -> options -> universes [agent_universe.index], MDL); } /* Do not use the client's requested parameter list. */ delete_option (&dhcp_universe, packet -> options, DHO_DHCP_PARAMETER_REQUEST_LIST); /* Set up the option buffer... */ outgoing.packet_length = cons_options (packet, outgoing.raw, (struct lease *)0, (struct client_state *)0, 0, packet -> options, options, &global_scope, 0, 0, 0, (struct data_string *)0, (char *)0); option_state_dereference (&options, MDL); /* memset (&raw.ciaddr, 0, sizeof raw.ciaddr);*/ raw.siaddr = packet -> interface -> primary_address; raw.giaddr = packet -> raw -> giaddr; memcpy (raw.chaddr, packet -> raw -> chaddr, sizeof raw.chaddr); raw.hlen = packet -> raw -> hlen; raw.htype = packet -> raw -> htype; raw.xid = packet -> raw -> xid; raw.secs = packet -> raw -> secs; raw.flags = packet -> raw -> flags | htons (BOOTP_BROADCAST); raw.hops = packet -> raw -> hops; raw.op = BOOTREPLY; /* Report what we're sending... */ log_info ("DHCPNAK on %s to %s via %s", piaddr (*cip), 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); #ifdef DEBUG_PACKET dump_packet (packet); dump_raw ((unsigned char *)packet -> raw, packet -> packet_length); dump_packet (&outgoing); dump_raw ((unsigned char *)&raw, outgoing.packet_length); #endif #if 0 hto.hbuf [0] = packet -> raw -> htype; hto.hlen = packet -> raw -> hlen; memcpy (&hto.hbuf [1], packet -> raw -> chaddr, hto.hlen); hto.hlen++; #endif /* Set up the common stuff... */ to.sin_family = AF_INET; #ifdef HAVE_SA_LEN to.sin_len = sizeof to; #endif memset (to.sin_zero, 0, sizeof to.sin_zero); memcpy (&from, myfrom.iabuf, sizeof from); /* Make sure that the packet is at least as big as a BOOTP packet. */ if (outgoing.packet_length < BOOTP_MIN_LEN) outgoing.packet_length = BOOTP_MIN_LEN; /* If this was gatewayed, send it back to the gateway. Otherwise, broadcast it on the local network. */ if (raw.giaddr.s_addr) { to.sin_addr = raw.giaddr; if (raw.giaddr.s_addr != htonl (INADDR_LOOPBACK)) to.sin_port = local_port; else to.sin_port = remote_port; /* for testing. */ if (fallback_interface) { result = send_packet (fallback_interface, packet, &raw, outgoing.packet_length, from, &to, &hto); return; } } else { to.sin_addr = limited_broadcast; to.sin_port = remote_port; } errno = 0; result = send_packet (packet -> interface, packet, &raw, outgoing.packet_length, from, &to, (struct hardware *)0); } void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp) struct packet *packet; struct lease *lease; unsigned int offer; TIME when; char *msg; int ms_nulltp; struct host_decl *hp; { struct lease *lt; struct lease_state *state; struct lease *next; struct host_decl *host = (struct host_decl *)0; TIME lease_time; TIME offered_lease_time; struct data_string d1; TIME min_lease_time; TIME max_lease_time; TIME default_lease_time; struct option_cache *oc; struct expression *expr; int status; isc_result_t result; int did_ping = 0; TIME ping_timeout; unsigned i, j; int s1, s2; int val; int ignorep; /* If we're already acking this lease, don't do it again. */ if (lease -> state) return; /* If the lease carries a host record, remember it. */ if (hp) host_reference (&host, hp, MDL); else if (lease -> host) host_reference (&host, lease -> host, MDL); /* Allocate a lease state structure... */ state = new_lease_state (MDL); if (!state) log_fatal ("unable to allocate lease state!"); state -> got_requested_address = packet -> got_requested_address; shared_network_reference (&state -> shared_network, packet -> interface -> shared_network, MDL); /* See if we got a server identifier option. */ if (lookup_option (&dhcp_universe, packet -> options, DHO_DHCP_SERVER_IDENTIFIER)) state -> got_server_identifier = 1; /* If there were agent options in the incoming packet, return them. Do not return the agent options if they were stashed on the lease. */ if (packet -> raw -> giaddr.s_addr && packet -> options -> universe_count > agent_universe.index && packet -> options -> universes [agent_universe.index] && (state -> options -> universe_count <= agent_universe.index || !state -> options -> universes [agent_universe.index]) && lease -> agent_options != ((struct option_chain_head *) packet -> options -> universes [agent_universe.index])) { option_chain_head_reference ((struct option_chain_head **) &(state -> options -> universes [agent_universe.index]), (struct option_chain_head *) packet -> options -> universes [agent_universe.index], MDL); } /* If we are offering a lease that is still currently valid, preserve the events. We need to do this because if the client does not REQUEST our offer, it will expire in 2 minutes, overriding the expire time in the currently in force lease. We want the expire events to be executed at that point. */ if (lease -> ends <= cur_time && offer != DHCPOFFER) { /* Get rid of any old expiry or release statements - by executing the statements below, we will be inserting new ones if there are any to insert. */ if (lease -> on_expiry) executable_statement_dereference (&lease -> on_expiry, MDL); if (lease -> on_commit) executable_statement_dereference (&lease -> on_commit, MDL); if (lease -> on_release) executable_statement_dereference (&lease -> on_release, MDL); } /* Execute statements in scope starting with the subnet scope. */ execute_statements_in_scope ((struct binding_value **)0, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, lease -> subnet -> group, (struct group *)0); /* If the lease is from a pool, run the pool scope. */ if (lease -> pool) (execute_statements_in_scope ((struct binding_value **)0, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, lease -> pool -> group, lease -> pool -> shared_network -> group)); /* Execute statements from class scopes. */ for (i = packet -> class_count; i > 0; i--) { execute_statements_in_scope ((struct binding_value **)0, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, packet -> classes [i - 1] -> group, (lease -> pool ? lease -> pool -> group : lease -> subnet -> group)); } /* See if the client is only supposed to have one lease at a time, and if so, find its other leases and release them. We can only do this on DHCPREQUEST. It's a little weird to do this before looking at permissions, because the client might not actually _get_ a lease after we've done the permission check, but the assumption for this option is that the client has exactly one network interface, and will only ever remember one lease. So if it sends a DHCPREQUEST, and doesn't get the lease, it's already forgotten about its old lease, so we can too. */ if (packet -> packet_type == DHCPREQUEST && (oc = lookup_option (&server_universe, state -> options, SV_ONE_LEASE_PER_CLIENT)) && evaluate_boolean_option_cache (&ignorep, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL)) { struct lease *seek; if (lease -> uid_len) { do { seek = (struct lease *)0; find_lease_by_uid (&seek, lease -> uid, lease -> uid_len, MDL); if (!seek) break; if (seek == lease && !seek -> n_uid) { lease_dereference (&seek, MDL); break; } next = (struct lease *)0; /* Don't release expired leases, and don't release the lease we're going to assign. */ next = (struct lease *)0; while (seek) { if (seek -> n_uid) lease_reference (&next, seek -> n_uid, MDL); if (seek != lease && seek -> binding_state != FTS_RELEASED && seek -> binding_state != FTS_EXPIRED && seek -> binding_state != FTS_RESET && seek -> binding_state != FTS_FREE && seek -> binding_state != FTS_BACKUP) break; lease_dereference (&seek, MDL); if (next) { lease_reference (&seek, next, MDL); lease_dereference (&next, MDL); } } if (next) lease_dereference (&next, MDL); if (seek) { release_lease (seek, packet); lease_dereference (&seek, MDL); } else break; } while (1); } if (!lease -> uid_len || (host && !host -> client_identifier.len && (oc = lookup_option (&server_universe, state -> options, SV_DUPLICATES)) && !evaluate_boolean_option_cache (&ignorep, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL))) { do { seek = (struct lease *)0; find_lease_by_hw_addr (&seek, lease -> hardware_addr.hbuf, lease -> hardware_addr.hlen, MDL); if (!seek) break; if (seek == lease && !seek -> n_hw) { lease_dereference (&seek, MDL); break; } next = (struct lease *)0; while (seek) { if (seek -> n_hw) lease_reference (&next, seek -> n_hw, MDL); if (seek != lease && seek -> binding_state != FTS_RELEASED && seek -> binding_state != FTS_EXPIRED && seek -> binding_state != FTS_RESET && seek -> binding_state != FTS_FREE && seek -> binding_state != FTS_BACKUP) break; lease_dereference (&seek, MDL); if (next) { lease_reference (&seek, next, MDL); lease_dereference (&next, MDL); } } if (next) lease_dereference (&next, MDL); if (seek) { release_lease (seek, packet); lease_dereference (&seek, MDL); } else break; } while (1); } } /* Make sure this packet satisfies the configured minimum number of seconds. */ memset (&d1, 0, sizeof d1); if (offer == DHCPOFFER && (oc = lookup_option (&server_universe, state -> options, SV_MIN_SECS))) { if (evaluate_option_cache (&d1, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL)) { if (d1.len && ntohs (packet -> raw -> secs) < d1.data [0]) { log_info ("%s: %d secs < %d", msg, ntohs (packet -> raw -> secs), d1.data [0]); data_string_forget (&d1, MDL); free_lease_state (state, MDL); if (host) host_dereference (&host, MDL); return; } data_string_forget (&d1, MDL); } } /* Try to find a matching host declaration for this lease. */ if (!host) { struct host_decl *hp = (struct host_decl *)0; struct host_decl *h; /* Try to find a host_decl that matches the client identifier or hardware address on the packet, and has no fixed IP address. If there is one, hang it off the lease so that its option definitions can be used. */ oc = lookup_option (&dhcp_universe, packet -> options, DHO_DHCP_CLIENT_IDENTIFIER); if (oc && evaluate_option_cache (&d1, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL)) { find_hosts_by_uid (&hp, d1.data, d1.len, MDL); data_string_forget (&d1, MDL); for (h = hp; h; h = h -> n_ipaddr) { if (!h -> fixed_addr) break; } if (h) host_reference (&host, h, MDL); } if (!host) { find_hosts_by_haddr (&hp, packet -> raw -> htype, packet -> raw -> chaddr, packet -> raw -> hlen, MDL); for (h = hp; h; h = h -> n_ipaddr) { if (!h -> fixed_addr) break; } if (h) host_reference (&host, h, MDL); } if (hp) host_dereference (&hp, MDL); } /* If we have a host_decl structure, run the options associated with its group. Wether the host decl struct is old or not. */ if (host) execute_statements_in_scope ((struct binding_value **)0, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, host -> group, (lease -> pool ? lease -> pool -> group : lease -> subnet -> group)); /* Drop the request if it's not allowed for this client. By default, unknown clients are allowed. */ if (!host && (oc = lookup_option (&server_universe, state -> options, SV_BOOT_UNKNOWN_CLIENTS)) && !evaluate_boolean_option_cache (&ignorep, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL)) { if (!ignorep) log_info ("%s: unknown client", msg); free_lease_state (state, MDL); if (host) host_dereference (&host, MDL); return; } /* Drop the request if it's not allowed for this client. */ if (!offer && (oc = lookup_option (&server_universe, state -> options, SV_ALLOW_BOOTP)) && !evaluate_boolean_option_cache (&ignorep, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL)) { if (!ignorep) log_info ("%s: bootp disallowed", msg); free_lease_state (state, MDL); if (host) host_dereference (&host, MDL); return; } /* Drop the request if booting is specifically denied. */ oc = lookup_option (&server_universe, state -> options, SV_ALLOW_BOOTING); if (oc && !evaluate_boolean_option_cache (&ignorep, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL)) { if (!ignorep) log_info ("%s: booting disallowed", msg); free_lease_state (state, MDL); if (host) host_dereference (&host, MDL); return; } /* If we are configured to do per-class billing, do it. */ if (have_billing_classes && !(lease -> flags & STATIC_LEASE)) { /* See if the lease is currently being billed to a class, and if so, whether or not it can continue to be billed to that class. */ if (lease -> billing_class) { for (i = 0; i < packet -> class_count; i++) if (packet -> classes [i] == lease -> billing_class) break; if (i == packet -> class_count) unbill_class (lease, lease -> billing_class); } /* If we don't have an active billing, see if we need one, and if we do, try to do so. */ if (!lease -> billing_class) { for (i = 0; i < packet -> class_count; i++) { if (packet -> classes [i] -> lease_limit) break; } if (i != packet -> class_count) { for (i = 0; i < packet -> class_count; i++) if ((packet -> classes [i] -> lease_limit) && bill_class (lease, packet -> classes [i])) break; if (i == packet -> class_count) { log_info ("%s: no available billing", msg); free_lease_state (state, MDL); if (host) host_dereference (&host, MDL); /* XXX possibly not necessary: */ return; } } /* If this is an offer, undo the billing. We go * through all the steps above to bill a class so * we can hit the 'no available billing' mark and * abort without offering. But it just doesn't make * sense to permanently bill a class for a non-active * lease. This means on REQUEST, we will bill this * lease again (if there is a REQUEST). */ if (offer == DHCPOFFER && lease->billing_class != NULL && lease->state != FTS_ACTIVE) unbill_class(lease, lease->billing_class); } } /* Figure out the filename. */ oc = lookup_option (&server_universe, state -> options, SV_FILENAME); if (oc) evaluate_option_cache (&state -> filename, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL); /* Choose a server name as above. */ oc = lookup_option (&server_universe, state -> options, SV_SERVER_NAME); if (oc) evaluate_option_cache (&state -> server_name, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL); /* At this point, we have a lease that we can offer the client. Now we construct a lease structure that contains what we want, and call supersede_lease to do the right thing with it. */ lt = (struct lease *)0; result = lease_allocate (<, MDL); if (result != ISC_R_SUCCESS) { log_info ("%s: can't allocate temporary lease structure: %s", msg, isc_result_totext (result)); free_lease_state (state, MDL); if (host) host_dereference (&host, MDL); return; } /* Use the ip address of the lease that we finally found in the database. */ lt -> ip_addr = lease -> ip_addr; /* Start now. */ lt -> starts = cur_time; /* Figure out how long a lease to assign. If this is a dynamic BOOTP lease, its duration must be infinite. */ if (offer) { default_lease_time = DEFAULT_DEFAULT_LEASE_TIME; if ((oc = lookup_option (&server_universe, state -> options, SV_DEFAULT_LEASE_TIME))) { 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)) default_lease_time = getULong (d1.data); data_string_forget (&d1, MDL); } } if ((oc = lookup_option (&dhcp_universe, packet -> options, DHO_DHCP_LEASE_TIME))) 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 == sizeof (u_int32_t)) { lease_time = getULong (d1.data); data_string_forget (&d1, MDL); } else { if (s1) data_string_forget (&d1, MDL); lease_time = default_lease_time; } /* See if there's a maximum lease time. */ max_lease_time = DEFAULT_MAX_LEASE_TIME; if ((oc = lookup_option (&server_universe, state -> options, SV_MAX_LEASE_TIME))) { 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)) max_lease_time = getULong (d1.data); data_string_forget (&d1, MDL); } } /* Enforce the maximum lease length. */ if (lease_time < 0 /* XXX */ || lease_time > max_lease_time) lease_time = max_lease_time; min_lease_time = DEFAULT_MIN_LEASE_TIME; if (min_lease_time > max_lease_time) min_lease_time = max_lease_time; if ((oc = lookup_option (&server_universe, state -> options, SV_MIN_LEASE_TIME))) { 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)) min_lease_time = getULong (d1.data); data_string_forget (&d1, MDL); } } if (lease_time < min_lease_time) { if (min_lease_time) lease_time = min_lease_time; else lease_time = default_lease_time; } #if defined (FAILOVER_PROTOCOL) /* Okay, we know the lease duration. Now check the failover state, if any. */ if (lease -> pool && lease -> pool -> failover_peer) { TIME new_lease_time = lease_time; dhcp_failover_state_t *peer = lease -> pool -> failover_peer; /* Copy previous lease failover ack-state. */ lt->tsfp = lease->tsfp; lt->atsfp = lease->atsfp; /* Update Client Last Transaction Time. */ lt->cltt = cur_time; /* Lease times less than MCLT are not a concern. */ if (lease_time > peer->mclt) { /* Each server can only offer a lease time * that is either equal to MCLT (at least), * or up to TSFP+MCLT. Only if the desired * lease time falls within TSFP+MCLT, can * the server allow it. */ if (lt->tsfp <= cur_time) new_lease_time = peer->mclt; else if ((cur_time + lease_time) > (lt->tsfp + peer->mclt)) new_lease_time = (lt->tsfp - cur_time) + peer->mclt; } /* Update potential expiry. Allow for the desired * lease time plus one half the actual (wether * modified downward or not) lease time, which is * actually an estimate of when the client will * renew. This way, the client will be able to get * the desired lease time upon renewal. */ if (offer == DHCPACK) { lt->tstp = cur_time + lease_time + (new_lease_time / 2); /* If we reduced the potential expiry time, * make sure we don't offer an old-expiry-time * lease for this lease before the change is * ack'd. */ if (lt->tstp < lt->tsfp) lt->tsfp = lt->tstp; } else lt->tstp = lease->tstp; /* Use failover-modified lease time. */ lease_time = new_lease_time; } #endif /* FAILOVER_PROTOCOL */ /* If the lease duration causes the time value to wrap, use the maximum expiry time. */ if (cur_time + lease_time < cur_time) state -> offered_expiry = MAX_TIME - 1; else state -> offered_expiry = cur_time + lease_time; if (when) lt -> ends = when; else lt -> ends = state -> offered_expiry; /* Don't make lease active until we actually get a DHCPREQUEST. */ if (offer == DHCPACK) lt -> next_binding_state = FTS_ACTIVE; else lt -> next_binding_state = lease -> binding_state; } else { lease_time = MAX_TIME - cur_time; if ((oc = lookup_option (&server_universe, state -> options, SV_BOOTP_LEASE_LENGTH))) { 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)) lease_time = getULong (d1.data); data_string_forget (&d1, MDL); } } if ((oc = lookup_option (&server_universe, state -> options, SV_BOOTP_LEASE_CUTOFF))) { 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)) lease_time = (getULong (d1.data) - cur_time); data_string_forget (&d1, MDL); } } lt -> ends = state -> offered_expiry = cur_time + lease_time; lt -> next_binding_state = FTS_ACTIVE; } lt -> timestamp = cur_time; /* Record the uid, if given... */ oc = lookup_option (&dhcp_universe, packet -> options, DHO_DHCP_CLIENT_IDENTIFIER); if (oc && evaluate_option_cache (&d1, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL)) { if (d1.len <= sizeof lt -> uid_buf) { memcpy (lt -> uid_buf, d1.data, d1.len); lt -> uid = lt -> uid_buf; lt -> uid_max = sizeof lt -> uid_buf; lt -> uid_len = d1.len; } else { unsigned char *tuid; lt -> uid_max = d1.len; lt -> uid_len = d1.len; tuid = (unsigned char *)dmalloc (lt -> uid_max, MDL); /* XXX inelegant */ if (!tuid) log_fatal ("no memory for large uid."); memcpy (tuid, d1.data, lt -> uid_len); lt -> uid = tuid; } data_string_forget (&d1, MDL); } if (host) { host_reference (< -> host, host, MDL); host_dereference (&host, MDL); } if (lease -> subnet) subnet_reference (< -> subnet, lease -> subnet, MDL); if (lease -> billing_class) class_reference (< -> billing_class, lease -> billing_class, MDL); /* Set a flag if this client is a broken client that NUL terminates string options and expects us to do likewise. */ if (ms_nulltp) lease -> flags |= MS_NULL_TERMINATION; else lease -> flags &= ~MS_NULL_TERMINATION; /* Save any bindings. */ if (lease -> scope) { binding_scope_reference (< -> scope, lease -> scope, MDL); binding_scope_dereference (&lease -> scope, MDL); } if (lease -> agent_options) option_chain_head_reference (< -> agent_options, lease -> agent_options, MDL); /* If we got relay agent information options, and the packet really looks like it came through a relay agent, and if this feature is not disabled, save the relay agent information options that came in with the packet, so that we can use them at renewal time when the packet won't have gone through a relay agent. */ if (packet -> raw -> giaddr.s_addr && packet -> options -> universe_count > agent_universe.index && packet -> options -> universes [agent_universe.index] && (state -> options -> universe_count <= agent_universe.index || state -> options -> universes [agent_universe.index] == packet -> options -> universes [agent_universe.index])) { oc = lookup_option (&server_universe, state -> options, SV_STASH_AGENT_OPTIONS); if (!oc || evaluate_boolean_option_cache (&ignorep, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL)) { if (lt -> agent_options) option_chain_head_dereference (< -> agent_options, MDL); option_chain_head_reference (< -> agent_options, (struct option_chain_head *) packet -> options -> universes [agent_universe.index], MDL); } } /* Replace the old lease hostname with the new one, if it's changed. */ oc = lookup_option (&dhcp_universe, packet -> options, DHO_HOST_NAME); if (oc) s1 = evaluate_option_cache (&d1, packet, (struct lease *)0, (struct client_state *)0, packet -> options, (struct option_state *)0, &global_scope, oc, MDL); else s1 = 0; if (oc && s1 && lease -> client_hostname && strlen (lease -> client_hostname) == d1.len && !memcmp (lease -> client_hostname, d1.data, d1.len)) { /* Hasn't changed. */ data_string_forget (&d1, MDL); lt -> client_hostname = lease -> client_hostname; lease -> client_hostname = (char *)0; } else if (oc && s1) { lt -> client_hostname = dmalloc (d1.len + 1, MDL); if (!lt -> client_hostname) log_error ("no memory for client hostname."); else { memcpy (lt -> client_hostname, d1.data, d1.len); lt -> client_hostname [d1.len] = 0; } data_string_forget (&d1, MDL); } /* Record the hardware address, if given... */ lt -> hardware_addr.hlen = packet -> raw -> hlen + 1; lt -> hardware_addr.hbuf [0] = packet -> raw -> htype; memcpy (< -> hardware_addr.hbuf [1], packet -> raw -> chaddr, sizeof packet -> raw -> chaddr); lt -> flags = lease -> flags & ~PERSISTENT_FLAGS; /* If there are statements to execute when the lease is committed, execute them. */ if (lease -> on_commit && (!offer || offer == DHCPACK)) { execute_statements ((struct binding_value **)0, packet, lt, (struct client_state *)0, packet -> options, state -> options, < -> scope, lease -> on_commit); if (lease -> on_commit) executable_statement_dereference (&lease -> on_commit, MDL); } #ifdef NSUPDATE /* Perform DDNS updates, if configured to. */ if ((!offer || offer == DHCPACK) && (!(oc = lookup_option (&server_universe, state -> options, SV_DDNS_UPDATES)) || evaluate_boolean_option_cache (&ignorep, packet, lt, (struct client_state *)0, packet -> options, state -> options, < -> scope, oc, MDL))) { ddns_updates (packet, lt, lease, state); } #endif /* NSUPDATE */ /* Don't call supersede_lease on a mocked-up lease. */ if (lease -> flags & STATIC_LEASE) { /* Copy the hardware address into the static lease structure. */ lease -> hardware_addr.hlen = packet -> raw -> hlen + 1; lease -> hardware_addr.hbuf [0] = packet -> raw -> htype; memcpy (&lease -> hardware_addr.hbuf [1], packet -> raw -> chaddr, sizeof packet -> raw -> chaddr); /* XXX */ } else { /* Install the new information about this lease in the database. If this is a DHCPACK or a dynamic BOOTREPLY and we can't write the lease, don't ACK it (or BOOTREPLY it) either. */ if (!supersede_lease (lease, lt, !offer || offer == DHCPACK, offer == DHCPACK, offer == DHCPACK)) { log_info ("%s: database update failed", msg); free_lease_state (state, MDL); lease_dereference (<, MDL); return; } } lease_dereference (<, MDL); /* Remember the interface on which the packet arrived. */ state -> ip = packet -> interface; /* Remember the giaddr, xid, secs, flags and hops. */ state -> giaddr = packet -> raw -> giaddr; state -> ciaddr = packet -> raw -> ciaddr; state -> xid = packet -> raw -> xid; state -> secs = packet -> raw -> secs; state -> bootp_flags = packet -> raw -> flags; state -> hops = packet -> raw -> hops; state -> offer = offer; /* If we're always supposed to broadcast to this client, set the broadcast bit in the bootp flags field. */ if ((oc = lookup_option (&server_universe, state -> options, SV_ALWAYS_BROADCAST)) && evaluate_boolean_option_cache (&ignorep, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL)) state -> bootp_flags |= htons (BOOTP_BROADCAST); /* Get the Maximum Message Size option from the packet, if one was sent. */ oc = lookup_option (&dhcp_universe, packet -> options, DHO_DHCP_MAX_MESSAGE_SIZE); if (oc && evaluate_option_cache (&d1, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL)) { if (d1.len == sizeof (u_int16_t)) state -> max_message_size = getUShort (d1.data); data_string_forget (&d1, MDL); } else { oc = lookup_option (&dhcp_universe, state -> options, DHO_DHCP_MAX_MESSAGE_SIZE); if (oc && evaluate_option_cache (&d1, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL)) { if (d1.len == sizeof (u_int16_t)) state -> max_message_size = getUShort (d1.data); data_string_forget (&d1, MDL); } } /* Get the Subnet Selection option from the packet, if one was sent. */ if ((oc = lookup_option (&dhcp_universe, packet -> options, DHO_SUBNET_SELECTION))) { /* Make a copy of the data. */ struct option_cache *noc = (struct option_cache *)0; if (option_cache_allocate (&noc, MDL)) { if (oc -> data.len) data_string_copy (&noc -> data, &oc -> data, MDL); if (oc -> expression) expression_reference (&noc -> expression, oc -> expression, MDL); if (oc -> option) noc -> option = oc -> option; } save_option (&dhcp_universe, state -> options, noc); option_cache_dereference (&noc, MDL); } /* Now, if appropriate, put in DHCP-specific options that override those. */ if (state -> offer) { i = DHO_DHCP_MESSAGE_TYPE; oc = (struct option_cache *)0; if (option_cache_allocate (&oc, MDL)) { if (make_const_data (&oc -> expression, &state -> offer, 1, 0, 0, MDL)) { oc -> option = dhcp_universe.options [i]; save_option (&dhcp_universe, state -> options, oc); } option_cache_dereference (&oc, MDL); } i = DHO_DHCP_SERVER_IDENTIFIER; if (!(oc = lookup_option (&dhcp_universe, state -> options, i))) { use_primary: oc = (struct option_cache *)0; if (option_cache_allocate (&oc, MDL)) { if (make_const_data (&oc -> expression, ((unsigned char *) &state -> ip -> primary_address), sizeof state -> ip -> primary_address, 0, 0, MDL)) { oc -> option = dhcp_universe.options [i]; save_option (&dhcp_universe, state -> options, oc); } option_cache_dereference (&oc, MDL); } state -> from.len = sizeof state -> ip -> primary_address; memcpy (state -> from.iabuf, &state -> ip -> primary_address, state -> from.len); } else { if (evaluate_option_cache (&d1, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL)) { if (!d1.len || d1.len > sizeof state -> from.iabuf) { data_string_forget (&d1, MDL); goto use_primary; } memcpy (state -> from.iabuf, d1.data, d1.len); state -> from.len = d1.len; data_string_forget (&d1, MDL); } else goto use_primary; } offered_lease_time = state -> offered_expiry - cur_time; putULong(state->expiry, (u_int32_t)offered_lease_time); i = DHO_DHCP_LEASE_TIME; if (lookup_option (&dhcp_universe, state -> options, i)) log_error ("dhcp-lease-time option for %s overridden.", inet_ntoa (state -> ciaddr)); oc = (struct option_cache *)0; if (option_cache_allocate (&oc, MDL)) { if (make_const_data(&oc->expression, state->expiry, 4, 0, 0, MDL)) { oc -> option = dhcp_universe.options [i]; save_option (&dhcp_universe, state -> options, oc); } option_cache_dereference (&oc, MDL); } /* Renewal time is lease time * 0.5. */ offered_lease_time /= 2; putULong(state->renewal, (u_int32_t)offered_lease_time); i = DHO_DHCP_RENEWAL_TIME; if (lookup_option (&dhcp_universe, state -> options, i)) log_error ("overriding dhcp-renewal-time for %s.", inet_ntoa (state -> ciaddr)); oc = (struct option_cache *)0; if (option_cache_allocate (&oc, MDL)) { if (make_const_data(&oc->expression, state->renewal, 4, 0, 0, MDL)) { oc -> option = dhcp_universe.options [i]; save_option (&dhcp_universe, state -> options, oc); } option_cache_dereference (&oc, MDL); } /* Rebinding time is lease time * 0.875. */ offered_lease_time += (offered_lease_time / 2 + offered_lease_time / 4); putULong(state->rebind, (u_int32_t)offered_lease_time); i = DHO_DHCP_REBINDING_TIME; if (lookup_option (&dhcp_universe, state -> options, i)) log_error ("overriding dhcp-rebinding-time for %s.", inet_ntoa (state -> ciaddr)); oc = (struct option_cache *)0; if (option_cache_allocate (&oc, MDL)) { if (make_const_data(&oc->expression, state->rebind, 4, 0, 0, MDL)) { oc -> option = dhcp_universe.options [i]; save_option (&dhcp_universe, state -> options, oc); } option_cache_dereference (&oc, MDL); } } else { state -> from.len = sizeof state -> ip -> primary_address; memcpy (state -> from.iabuf, &state -> ip -> primary_address, state -> from.len); } /* Figure out the address of the boot file server. */ memset (&state -> siaddr, 0, sizeof state -> siaddr); if ((oc = lookup_option (&server_universe, state -> options, SV_NEXT_SERVER))) { if (evaluate_option_cache (&d1, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL)) { /* If there was more than one answer, take the first. */ if (d1.len >= 4 && d1.data) memcpy (&state -> siaddr, d1.data, 4); data_string_forget (&d1, MDL); } } /* Use the subnet mask from the subnet declaration if no other mask has been provided. */ i = DHO_SUBNET_MASK; if (!lookup_option (&dhcp_universe, state -> options, i)) { oc = (struct option_cache *)0; if (option_cache_allocate (&oc, MDL)) { if (make_const_data (&oc -> expression, lease -> subnet -> netmask.iabuf, lease -> subnet -> netmask.len, 0, 0, MDL)) { oc -> option = dhcp_universe.options [i]; save_option (&dhcp_universe, state -> options, oc); } option_cache_dereference (&oc, MDL); } } /* Use the hostname from the host declaration if there is one and no hostname has otherwise been provided, and if the use-host-decl-name flag is set. */ i = DHO_HOST_NAME; j = SV_USE_HOST_DECL_NAMES; if (!lookup_option (&dhcp_universe, state -> options, i) && lease -> host && lease -> host -> name && (evaluate_boolean_option_cache (&ignorep, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, lookup_option (&server_universe, state -> options, j), MDL))) { oc = (struct option_cache *)0; if (option_cache_allocate (&oc, MDL)) { if (make_const_data (&oc -> expression, ((unsigned char *) lease -> host -> name), strlen (lease -> host -> name), 1, 0, MDL)) { oc -> option = dhcp_universe.options [i]; save_option (&dhcp_universe, state -> options, oc); } option_cache_dereference (&oc, MDL); } } /* If we don't have a hostname yet, and we've been asked to do a reverse lookup to find the hostname, do it. */ j = SV_GET_LEASE_HOSTNAMES; if (!lookup_option (&server_universe, state -> options, i) && (evaluate_boolean_option_cache (&ignorep, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, lookup_option (&server_universe, state -> options, j), MDL))) { struct in_addr ia; struct hostent *h; memcpy (&ia, lease -> ip_addr.iabuf, 4); h = gethostbyaddr ((char *)&ia, sizeof ia, AF_INET); if (!h) log_error ("No hostname for %s", inet_ntoa (ia)); else { oc = (struct option_cache *)0; if (option_cache_allocate (&oc, MDL)) { if (make_const_data (&oc -> expression, ((unsigned char *) h -> h_name), strlen (h -> h_name) + 1, 1, 1, MDL)) { oc -> option = dhcp_universe.options [i]; save_option (&dhcp_universe, state -> options, oc); } option_cache_dereference (&oc, MDL); } } } /* If so directed, use the leased IP address as the router address. This supposedly makes Win95 machines ARP for all IP addresses, so if the local router does proxy arp, you win. */ if (evaluate_boolean_option_cache (&ignorep, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, lookup_option (&server_universe, state -> options, SV_USE_LEASE_ADDR_FOR_DEFAULT_ROUTE), MDL)) { i = DHO_ROUTERS; oc = lookup_option (&dhcp_universe, state -> options, i); if (!oc) { oc = (struct option_cache *)0; if (option_cache_allocate (&oc, MDL)) { if (make_const_data (&oc -> expression, lease -> ip_addr.iabuf, lease -> ip_addr.len, 0, 0, MDL)) { oc -> option = dhcp_universe.options [i]; save_option (&dhcp_universe, state -> options, oc); } option_cache_dereference (&oc, MDL); } } } /* If a site option space has been specified, use that for site option codes. */ i = SV_SITE_OPTION_SPACE; if ((oc = lookup_option (&server_universe, state -> options, i)) && evaluate_option_cache (&d1, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL)) { struct universe *u = (struct universe *)0; if (!universe_hash_lookup (&u, universe_hash, (const char *)d1.data, d1.len, MDL)) { log_error ("unknown option space %s.", d1.data); return; } state -> options -> site_universe = u -> index; state -> options -> site_code_min = 128; /* XXX */ data_string_forget (&d1, MDL); } else { state -> options -> site_code_min = 0; state -> options -> site_universe = dhcp_universe.index; } /* If the client has provided a list of options that it wishes returned, use it to prioritize. If there's a parameter request list in scope, use that in preference. Otherwise use the default priority list. */ oc = lookup_option (&dhcp_universe, state -> options, DHO_DHCP_PARAMETER_REQUEST_LIST); if (!oc) oc = lookup_option (&dhcp_universe, packet -> options, DHO_DHCP_PARAMETER_REQUEST_LIST); if (oc) evaluate_option_cache (&state -> parameter_request_list, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL); #ifdef DEBUG_PACKET dump_packet (packet); dump_raw ((unsigned char *)packet -> raw, packet -> packet_length); #endif lease -> state = state; log_info ("%s", msg); /* Hang the packet off the lease state. */ packet_reference (&lease -> state -> packet, packet, MDL); /* If this is a DHCPOFFER, ping the lease address before actually sending the offer. */ if (offer == DHCPOFFER && !(lease -> flags & STATIC_LEASE) && cur_time - lease -> timestamp > 60 && (!(oc = lookup_option (&server_universe, state -> options, SV_PING_CHECKS)) || evaluate_boolean_option_cache (&ignorep, packet, lease, (struct client_state *)0, packet -> options, state -> options, &lease -> scope, oc, MDL))) { lease -> timestamp = cur_time; icmp_echorequest (&lease -> ip_addr); /* Determine wether to use configured or default ping timeout. */ if ((oc = lookup_option (&server_universe, state -> options, SV_PING_TIMEOUT)) && evaluate_option_cache (&d1, packet, lease, NULL, packet -> options, state -> options, &lease -> scope, oc, MDL)) { if (d1.len == sizeof (u_int32_t)) ping_timeout = getULong (d1.data); else ping_timeout = DEFAULT_PING_TIMEOUT; data_string_forget (&d1, MDL); } else ping_timeout = DEFAULT_PING_TIMEOUT; #ifdef DEBUG log_debug ("Ping timeout: %ld", (long)ping_timeout); #endif add_timeout (cur_time + ping_timeout, lease_ping_timeout, lease, (tvref_t)lease_reference, (tvunref_t)lease_dereference); ++outstanding_pings; } else { lease -> timestamp = cur_time; dhcp_reply (lease); } } void dhcp_reply (lease) struct lease *lease; { int bufs = 0; unsigned packet_length; struct dhcp_packet raw; struct sockaddr_in to; struct in_addr from; struct hardware hto; int result; int i; struct lease_state *state = lease -> state; int nulltp, bootpp, unicastp = 1; struct option_tag *ot, *not; struct data_string d1; struct option_cache *oc; const char *s; if (!state) log_fatal ("dhcp_reply was supplied lease with no state!"); /* Compose a response for the client... */ memset (&raw, 0, sizeof raw); memset (&d1, 0, sizeof d1); /* Copy in the filename if given; otherwise, flag the filename buffer as available for options. */ if (state -> filename.len && state -> filename.data) { memcpy (raw.file, state -> filename.data, state -> filename.len > sizeof raw.file ? sizeof raw.file : state -> filename.len); if (sizeof raw.file > state -> filename.len) memset (&raw.file [state -> filename.len], 0, (sizeof raw.file) - state -> filename.len); } else bufs |= 1; /* Copy in the server name if given; otherwise, flag the server_name buffer as available for options. */ if (state -> server_name.len && state -> server_name.data) { memcpy (raw.sname, state -> server_name.data, state -> server_name.len > sizeof raw.sname ? sizeof raw.sname : state -> server_name.len); if (sizeof raw.sname > state -> server_name.len) memset (&raw.sname [state -> server_name.len], 0, (sizeof raw.sname) - state -> server_name.len); } else bufs |= 2; /* XXX */ memcpy (raw.chaddr, &lease -> hardware_addr.hbuf [1], sizeof raw.chaddr); raw.hlen = lease -> hardware_addr.hlen - 1; raw.htype = lease -> hardware_addr.hbuf [0]; /* See if this is a Microsoft client that NUL-terminates its strings and expects us to do likewise... */ if (lease -> flags & MS_NULL_TERMINATION) nulltp = 1; else nulltp = 0; /* See if this is a bootp client... */ if (state -> offer) bootpp = 0; else bootpp = 1; /* Insert such options as will fit into the buffer. */ packet_length = cons_options (state -> packet, &raw, lease, (struct client_state *)0, state -> max_message_size, state -> packet -> options, state -> options, &global_scope, bufs, nulltp, bootpp, &state -> parameter_request_list, (char *)0); memcpy (&raw.ciaddr, &state -> ciaddr, sizeof raw.ciaddr); memcpy (&raw.yiaddr, lease -> ip_addr.iabuf, 4); raw.siaddr = state -> siaddr; raw.giaddr = state -> giaddr; raw.xid = state -> xid; raw.secs = state -> secs; raw.flags = state -> bootp_flags; raw.hops = state -> hops; raw.op = BOOTREPLY; if (lease -> client_hostname) { if ((strlen (lease -> client_hostname) <= 64) && db_printable (lease -> client_hostname)) s = lease -> client_hostname; else s = "Hostname Unsuitable for Printing"; } else s = (char *)0; /* Say what we're doing... */ log_info ("%s on %s to %s %s%s%svia %s", (state -> offer ? (state -> offer == DHCPACK ? "DHCPACK" : "DHCPOFFER") : "BOOTREPLY"), piaddr (lease -> ip_addr), (lease -> hardware_addr.hlen ? print_hw_addr (lease -> hardware_addr.hbuf [0], lease -> hardware_addr.hlen - 1, &lease -> hardware_addr.hbuf [1]) : print_hex_1 (lease -> uid_len, lease -> uid, lease -> uid_len)), s ? "(" : "", s ? s : "", s ? ") " : "", (state -> giaddr.s_addr ? inet_ntoa (state -> giaddr) : state -> ip -> name)); /* Set up the hardware address... */ hto.hlen = lease -> hardware_addr.hlen; memcpy (hto.hbuf, lease -> hardware_addr.hbuf, hto.hlen); to.sin_family = AF_INET; #ifdef HAVE_SA_LEN to.sin_len = sizeof to; #endif memset (to.sin_zero, 0, sizeof to.sin_zero); #ifdef DEBUG_PACKET dump_raw ((unsigned char *)&raw, packet_length); #endif /* Make sure outgoing packets are at least as big as a BOOTP packet. */ if (packet_length < BOOTP_MIN_LEN) packet_length = BOOTP_MIN_LEN; /* If this was gatewayed, send it back to the gateway... */ if (raw.giaddr.s_addr) { to.sin_addr = raw.giaddr; if (raw.giaddr.s_addr != htonl (INADDR_LOOPBACK)) to.sin_port = local_port; else to.sin_port = remote_port; /* For debugging. */ if (fallback_interface) { result = send_packet (fallback_interface, (struct packet *)0, &raw, packet_length, raw.siaddr, &to, (struct hardware *)0); free_lease_state (state, MDL); lease -> state = (struct lease_state *)0; return; } /* If the client is RENEWING, unicast to the client using the regular IP stack. Some clients, particularly those that follow RFC1541, are buggy, and send both ciaddr and server identifier. We deal with this situation by assuming that if we got both dhcp-server-identifier and ciaddr, and giaddr was not set, then the client is on the local network, and we can therefore unicast or broadcast to it successfully. A client in REQUESTING state on another network that's making this mistake will have set giaddr, and will therefore get a relayed response from the above code. */ } else if (raw.ciaddr.s_addr && !((state -> got_server_identifier || (raw.flags & htons (BOOTP_BROADCAST))) && /* XXX This won't work if giaddr isn't zero, but it is: */ (state -> shared_network == lease -> subnet -> shared_network)) && state -> offer == DHCPACK) { to.sin_addr = raw.ciaddr; to.sin_port = remote_port; if (fallback_interface) { result = send_packet (fallback_interface, (struct packet *)0, &raw, packet_length, raw.siaddr, &to, (struct hardware *)0); free_lease_state (state, MDL); lease -> state = (struct lease_state *)0; 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)) && can_unicast_without_arp (state -> ip)) { to.sin_addr = raw.yiaddr; to.sin_port = remote_port; /* Otherwise, broadcast it on the local network. */ } else { to.sin_addr = limited_broadcast; to.sin_port = remote_port; if (!(lease -> flags & UNICAST_BROADCAST_HACK)) unicastp = 0; } memcpy (&from, state -> from.iabuf, sizeof from); result = send_packet (state -> ip, (struct packet *)0, &raw, packet_length, from, &to, unicastp ? &hto : (struct hardware *)0); /* Free all of the entries in the option_state structure now that we're done with them. */ free_lease_state (state, MDL); lease -> state = (struct lease_state *)0; } int find_lease (struct lease **lp, struct packet *packet, struct shared_network *share, int *ours, int *peer_has_leases, struct lease *ip_lease_in, const char *file, int line) { struct lease *uid_lease = (struct lease *)0; struct lease *ip_lease = (struct lease *)0; struct lease *hw_lease = (struct lease *)0; struct lease *lease = (struct lease *)0; struct iaddr cip; struct host_decl *hp = (struct host_decl *)0; struct host_decl *host = (struct host_decl *)0; struct lease *fixed_lease = (struct lease *)0; struct lease *next = (struct lease *)0; struct option_cache *oc; struct data_string d1; int have_client_identifier = 0; struct data_string client_identifier; int status; struct hardware h; /* Quick check to see if the peer has leases. */ if (peer_has_leases) { struct pool *pool; for (pool = share->pools ; pool ; pool = pool->next) { dhcp_failover_state_t *peer = pool->failover_peer; if (peer && ((peer->i_am == primary && pool->backup_leases) || (peer->i_am == secondary && pool->free_leases))) { *peer_has_leases = 1; break; } } } if (packet -> raw -> ciaddr.s_addr) { cip.len = 4; memcpy (cip.iabuf, &packet -> raw -> ciaddr, 4); } else { /* Look up the requested address. */ oc = lookup_option (&dhcp_universe, packet -> options, DHO_DHCP_REQUESTED_ADDRESS); memset (&d1, 0, sizeof d1); if (oc && evaluate_option_cache (&d1, packet, (struct lease *)0, (struct client_state *)0, packet -> options, (struct option_state *)0, &global_scope, oc, MDL)) { packet -> got_requested_address = 1; cip.len = 4; memcpy (cip.iabuf, d1.data, cip.len); data_string_forget (&d1, MDL); } else cip.len = 0; } /* Try to find a host or lease that's been assigned to the specified unique client identifier. */ oc = lookup_option (&dhcp_universe, packet -> options, DHO_DHCP_CLIENT_IDENTIFIER); memset (&client_identifier, 0, sizeof client_identifier); if (oc && evaluate_option_cache (&client_identifier, packet, (struct lease *)0, (struct client_state *)0, packet -> options, (struct option_state *)0, &global_scope, oc, MDL)) { /* Remember this for later. */ have_client_identifier = 1; /* First, try to find a fixed host entry for the specified client identifier... */ if (find_hosts_by_uid (&hp, client_identifier.data, client_identifier.len, MDL)) { /* Remember if we know of this client. */ packet -> known = 1; mockup_lease (&fixed_lease, packet, share, hp); } #if defined (DEBUG_FIND_LEASE) if (fixed_lease) { log_info ("Found host for client identifier: %s.", piaddr (fixed_lease -> ip_addr)); } #endif if (hp) { if (!fixed_lease) /* Save the host if we found one. */ host_reference (&host, hp, MDL); host_dereference (&hp, MDL); } find_lease_by_uid (&uid_lease, client_identifier.data, client_identifier.len, MDL); } /* If we didn't find a fixed lease using the uid, try doing it with the hardware address... */ if (!fixed_lease && !host) { if (find_hosts_by_haddr (&hp, packet -> raw -> htype, packet -> raw -> chaddr, packet -> raw -> hlen, MDL)) { /* Remember if we know of this client. */ packet -> known = 1; if (host) host_dereference (&host, MDL); host_reference (&host, hp, MDL); host_dereference (&hp, MDL); mockup_lease (&fixed_lease, packet, share, host); #if defined (DEBUG_FIND_LEASE) if (fixed_lease) { log_info ("Found host for link address: %s.", piaddr (fixed_lease -> ip_addr)); } #endif } } /* If fixed_lease is present but does not match the requested IP address, and this is a DHCPREQUEST, then we can't return any other lease, so we might as well return now. */ if (packet -> packet_type == DHCPREQUEST && fixed_lease && (fixed_lease -> ip_addr.len != cip.len || memcmp (fixed_lease -> ip_addr.iabuf, cip.iabuf, cip.len))) { if (ours) *ours = 1; strcpy (dhcp_message, "requested address is incorrect"); #if defined (DEBUG_FIND_LEASE) log_info ("Client's fixed-address %s doesn't match %s%s", piaddr (fixed_lease -> ip_addr), "request ", print_dotted_quads (cip.len, cip.iabuf)); #endif goto out; } /* If we found leases matching the client identifier, loop through the n_uid pointer looking for one that's actually valid. We can't do this until we get here because we depend on packet -> known, which may be set by either the uid host lookup or the haddr host lookup. */ while (uid_lease) { #if defined (DEBUG_FIND_LEASE) log_info ("trying next lease matching client id: %s", piaddr (uid_lease -> ip_addr)); #endif #if defined (FAILOVER_PROTOCOL) /* When failover is active, it's possible that there could be two "free" leases for the same uid, but only one of them that's available for this failover peer to allocate. */ if (uid_lease -> binding_state != FTS_ACTIVE && !lease_mine_to_reallocate (uid_lease)) { #if defined (DEBUG_FIND_LEASE) log_info ("not mine to allocate: %s", piaddr (uid_lease -> ip_addr)); #endif goto n_uid; } #endif if (uid_lease -> subnet -> shared_network != share) { #if defined (DEBUG_FIND_LEASE) log_info ("wrong network segment: %s", piaddr (uid_lease -> ip_addr)); #endif goto n_uid; } if ((uid_lease -> pool -> prohibit_list && permitted (packet, uid_lease -> pool -> prohibit_list)) || (uid_lease -> pool -> permit_list && !permitted (packet, uid_lease -> pool -> permit_list))) { #if defined (DEBUG_FIND_LEASE) log_info ("not permitted: %s", piaddr (uid_lease -> ip_addr)); #endif n_uid: if (uid_lease -> n_uid) lease_reference (&next, uid_lease -> n_uid, MDL); if (!packet -> raw -> ciaddr.s_addr) release_lease (uid_lease, packet); lease_dereference (&uid_lease, MDL); if (next) { lease_reference (&uid_lease, next, MDL); lease_dereference (&next, MDL); } continue; } break; } #if defined (DEBUG_FIND_LEASE) if (uid_lease) log_info ("Found lease for client id: %s.", piaddr (uid_lease -> ip_addr)); #endif /* Find a lease whose hardware address matches, whose client identifier matches, that's permitted, and that's on the correct subnet. */ h.hlen = packet -> raw -> hlen + 1; h.hbuf [0] = packet -> raw -> htype; memcpy (&h.hbuf [1], packet -> raw -> chaddr, packet -> raw -> hlen); find_lease_by_hw_addr (&hw_lease, h.hbuf, h.hlen, MDL); while (hw_lease) { #if defined (DEBUG_FIND_LEASE) log_info ("trying next lease matching hw addr: %s", piaddr (hw_lease -> ip_addr)); #endif #if defined (FAILOVER_PROTOCOL) /* When failover is active, it's possible that there could be two "free" leases for the same uid, but only one of them that's available for this failover peer to allocate. */ if (hw_lease -> binding_state != FTS_ACTIVE && !lease_mine_to_reallocate (hw_lease)) { #if defined (DEBUG_FIND_LEASE) log_info ("not mine to allocate: %s", piaddr (hw_lease -> ip_addr)); #endif goto n_hw; } #endif if (hw_lease -> binding_state != FTS_FREE && hw_lease -> binding_state != FTS_BACKUP && hw_lease -> uid && (!have_client_identifier || hw_lease -> uid_len != client_identifier.len || memcmp (hw_lease -> uid, client_identifier.data, hw_lease -> uid_len))) { #if defined (DEBUG_FIND_LEASE) log_info ("wrong client identifier: %s", piaddr (hw_lease -> ip_addr)); #endif goto n_hw; continue; } if (hw_lease -> subnet -> shared_network != share) { #if defined (DEBUG_FIND_LEASE) log_info ("wrong network segment: %s", piaddr (hw_lease -> ip_addr)); #endif goto n_hw; continue; } if ((hw_lease -> pool -> prohibit_list && permitted (packet, hw_lease -> pool -> prohibit_list)) || (hw_lease -> pool -> permit_list && !permitted (packet, hw_lease -> pool -> permit_list))) { #if defined (DEBUG_FIND_LEASE) log_info ("not permitted: %s", piaddr (hw_lease -> ip_addr)); #endif if (!packet -> raw -> ciaddr.s_addr) release_lease (hw_lease, packet); n_hw: if (hw_lease -> n_hw) lease_reference (&next, hw_lease -> n_hw, MDL); lease_dereference (&hw_lease, MDL); if (next) { lease_reference (&hw_lease, next, MDL); lease_dereference (&next, MDL); } continue; } break; } #if defined (DEBUG_FIND_LEASE) if (hw_lease) log_info ("Found lease for hardware address: %s.", piaddr (hw_lease -> ip_addr)); #endif /* Try to find a lease that's been allocated to the client's IP address. */ if (ip_lease_in) lease_reference (&ip_lease, ip_lease_in, MDL); else if (cip.len) find_lease_by_ip_addr (&ip_lease, cip, MDL); #if defined (DEBUG_FIND_LEASE) if (ip_lease) log_info ("Found lease for requested address: %s.", piaddr (ip_lease -> ip_addr)); #endif /* If ip_lease is valid at this point, set ours to one, so that even if we choose a different lease, we know that the address the client was requesting was ours, and thus we can NAK it. */ if (ip_lease && ours) *ours = 1; /* If the requested IP address isn't on the network the packet came from, don't use it. Allow abandoned leases to be matched here - if the client is requesting it, there's a decent chance that it's because the lease database got trashed and a client that thought it had this lease answered an ARP or PING, causing the lease to be abandoned. If so, this request probably came from that client. */ if (ip_lease && (ip_lease -> subnet -> shared_network != share)) { if (ours) *ours = 1; #if defined (DEBUG_FIND_LEASE) log_info ("...but it was on the wrong shared network."); #endif strcpy (dhcp_message, "requested address on bad subnet"); lease_dereference (&ip_lease, MDL); } /* Toss ip_lease if it hasn't yet expired and doesn't belong to the client. */ if (ip_lease && (ip_lease -> uid ? (!have_client_identifier || ip_lease -> uid_len != client_identifier.len || memcmp (ip_lease -> uid, client_identifier.data, ip_lease -> uid_len)) : (ip_lease -> hardware_addr.hbuf [0] != packet -> raw -> htype || ip_lease -> hardware_addr.hlen != packet -> raw -> hlen + 1 || memcmp (&ip_lease -> hardware_addr.hbuf [1], packet -> raw -> chaddr, (unsigned)(ip_lease -> hardware_addr.hlen - 1))))) { /* If we're not doing failover, the only state in which we can allocate this lease to the client is FTS_FREE. If we are doing failover, things are more complicated. If the lease is free or backup, we let the caller decide whether or not to give it out. */ if (ip_lease -> binding_state != FTS_FREE && ip_lease -> binding_state != FTS_BACKUP) { #if defined (DEBUG_FIND_LEASE) log_info ("rejecting lease for requested address."); #endif /* If we're rejecting it because the peer has it, don't set "ours", because we shouldn't NAK. */ if (ours && ip_lease -> binding_state != FTS_ACTIVE) *ours = 0; lease_dereference (&ip_lease, MDL); } } /* If we got an ip_lease and a uid_lease or hw_lease, and ip_lease is not active, and is not ours to reallocate, forget about it. */ if (ip_lease && (uid_lease || hw_lease) && ip_lease -> binding_state != FTS_ACTIVE && !lease_mine_to_reallocate (ip_lease) && packet -> packet_type == DHCPDISCOVER) { #if defined (DEBUG_FIND_LEASE) log_info ("ip lease not ours to offer."); #endif lease_dereference (&ip_lease, MDL); } /* If for some reason the client has more than one lease on the subnet that matches its uid, pick the one that it asked for and (if we can) free the other. */ if (ip_lease && ip_lease -> binding_state == FTS_ACTIVE && ip_lease -> uid && ip_lease != uid_lease) { if (have_client_identifier && (ip_lease -> uid_len == client_identifier.len) && !memcmp (client_identifier.data, ip_lease -> uid, ip_lease -> uid_len)) { if (uid_lease) { if (uid_lease -> binding_state == FTS_ACTIVE) { log_error ("client %s has duplicate%s on %s", (print_hw_addr (packet -> raw -> htype, packet -> raw -> hlen, packet -> raw -> chaddr)), " leases", (ip_lease -> subnet -> shared_network -> name)); /* If the client is REQUESTing the lease, it shouldn't still be using the old one, so we can free it for allocation. */ if (uid_lease && uid_lease -> binding_state == FTS_ACTIVE && !packet -> raw -> ciaddr.s_addr && (share == uid_lease -> subnet -> shared_network) && packet -> packet_type == DHCPREQUEST) release_lease (uid_lease, packet); } lease_dereference (&uid_lease, MDL); lease_reference (&uid_lease, ip_lease, MDL); } } /* If we get to here and fixed_lease is not null, that means that there are both a dynamic lease and a fixed-address declaration for the same IP address. */ if (packet -> packet_type == DHCPREQUEST && fixed_lease) { lease_dereference (&fixed_lease, MDL); db_conflict: log_error ("Dynamic and static leases present for %s.", piaddr (cip)); log_error ("Remove host declaration %s or remove %s", (fixed_lease && fixed_lease -> host ? (fixed_lease -> host -> name ? fixed_lease -> host -> name : piaddr (cip)) : piaddr (cip)), piaddr (cip)); log_error ("from the dynamic address pool for %s", ip_lease -> subnet -> shared_network -> name ); if (fixed_lease) lease_dereference (&ip_lease, MDL); strcpy (dhcp_message, "database conflict - call for help!"); } if (ip_lease && ip_lease != uid_lease) { #if defined (DEBUG_FIND_LEASE) log_info ("requested address not available."); #endif lease_dereference (&ip_lease, MDL); } } /* If we get to here with both fixed_lease and ip_lease not null, then we have a configuration file bug. */ if (packet -> packet_type == DHCPREQUEST && fixed_lease && ip_lease) goto db_conflict; /* Toss extra pointers to the same lease... */ if (hw_lease && hw_lease == uid_lease) { #if defined (DEBUG_FIND_LEASE) log_info ("hardware lease and uid lease are identical."); #endif lease_dereference (&hw_lease, MDL); } if (ip_lease && ip_lease == hw_lease) { lease_dereference (&hw_lease, MDL); #if defined (DEBUG_FIND_LEASE) log_info ("hardware lease and ip lease are identical."); #endif } if (ip_lease && ip_lease == uid_lease) { lease_dereference (&uid_lease, MDL); #if defined (DEBUG_FIND_LEASE) log_info ("uid lease and ip lease are identical."); #endif } /* Make sure the client is permitted to use the requested lease. */ if (ip_lease && ((ip_lease -> pool -> prohibit_list && permitted (packet, ip_lease -> pool -> prohibit_list)) || (ip_lease -> pool -> permit_list && !permitted (packet, ip_lease -> pool -> permit_list)))) { if (!packet->raw->ciaddr.s_addr && (ip_lease->binding_state == FTS_ACTIVE)) release_lease (ip_lease, packet); lease_dereference (&ip_lease, MDL); } if (uid_lease && ((uid_lease -> pool -> prohibit_list && permitted (packet, uid_lease -> pool -> prohibit_list)) || (uid_lease -> pool -> permit_list && !permitted (packet, uid_lease -> pool -> permit_list)))) { if (!packet -> raw -> ciaddr.s_addr) release_lease (uid_lease, packet); lease_dereference (&uid_lease, MDL); } if (hw_lease && ((hw_lease -> pool -> prohibit_list && permitted (packet, hw_lease -> pool -> prohibit_list)) || (hw_lease -> pool -> permit_list && !permitted (packet, hw_lease -> pool -> permit_list)))) { if (!packet -> raw -> ciaddr.s_addr) release_lease (hw_lease, packet); lease_dereference (&hw_lease, MDL); } /* If we've already eliminated the lease, it wasn't there to begin with. If we have come up with a matching lease, set the message to bad network in case we have to throw it out. */ if (!ip_lease) { strcpy (dhcp_message, "requested address not available"); } /* If this is a DHCPREQUEST, make sure the lease we're going to return matches the requested IP address. If it doesn't, don't return a lease at all. */ if (packet -> packet_type == DHCPREQUEST && !ip_lease && !fixed_lease) { #if defined (DEBUG_FIND_LEASE) log_info ("no applicable lease found for DHCPREQUEST."); #endif goto out; } /* At this point, if fixed_lease is nonzero, we can assign it to this client. */ if (fixed_lease) { lease_reference (&lease, fixed_lease, MDL); lease_dereference (&fixed_lease, MDL); #if defined (DEBUG_FIND_LEASE) log_info ("choosing fixed address."); #endif } /* If we got a lease that matched the ip address and don't have a better offer, use that; otherwise, release it. */ if (ip_lease) { if (lease) { if (!packet -> raw -> ciaddr.s_addr) release_lease (ip_lease, packet); #if defined (DEBUG_FIND_LEASE) log_info ("not choosing requested address (!)."); #endif } else { #if defined (DEBUG_FIND_LEASE) log_info ("choosing lease on requested address."); #endif lease_reference (&lease, ip_lease, MDL); if (lease -> host) host_dereference (&lease -> host, MDL); } lease_dereference (&ip_lease, MDL); } /* If we got a lease that matched the client identifier, we may want to use it, but if we already have a lease we like, we must free the lease that matched the client identifier. */ if (uid_lease) { if (lease) { log_error("uid lease %s for client %s is duplicate " "on %s", piaddr(uid_lease->ip_addr), print_hw_addr(packet->raw->htype, packet->raw->hlen, packet->raw->chaddr), uid_lease->subnet->shared_network->name); if (!packet -> raw -> ciaddr.s_addr && packet -> packet_type == DHCPREQUEST && uid_lease -> binding_state == FTS_ACTIVE) release_lease (uid_lease, packet); #if defined (DEBUG_FIND_LEASE) log_info ("not choosing uid lease."); #endif } else { lease_reference (&lease, uid_lease, MDL); if (lease -> host) host_dereference (&lease -> host, MDL); #if defined (DEBUG_FIND_LEASE) log_info ("choosing uid lease."); #endif } lease_dereference (&uid_lease, MDL); } /* The lease that matched the hardware address is treated likewise. */ if (hw_lease) { if (lease) { #if defined (DEBUG_FIND_LEASE) log_info ("not choosing hardware lease."); #endif } else { /* We're a little lax here - if the client didn't send a client identifier and it's a bootp client, but the lease has a client identifier, we still let the client have a lease. */ if (!hw_lease -> uid_len || (have_client_identifier ? (hw_lease -> uid_len == client_identifier.len && !memcmp (hw_lease -> uid, client_identifier.data, client_identifier.len)) : packet -> packet_type == 0)) { lease_reference (&lease, hw_lease, MDL); if (lease -> host) host_dereference (&lease -> host, MDL); #if defined (DEBUG_FIND_LEASE) log_info ("choosing hardware lease."); #endif } else { #if defined (DEBUG_FIND_LEASE) log_info ("not choosing hardware lease: %s.", "uid mismatch"); #endif } } lease_dereference (&hw_lease, MDL); } /* If we found a host_decl but no matching address, try to find a host_decl that has no address, and if there is one, hang it off the lease so that we can use the supplied options. */ if (lease && host && !lease -> host) { struct host_decl *p = (struct host_decl *)0; struct host_decl *n = (struct host_decl *)0; host_reference (&p, host, MDL); while (p) { if (!p -> fixed_addr) { host_reference (&lease -> host, p, MDL); host_dereference (&p, MDL); break; } if (p -> n_ipaddr) host_reference (&n, p -> n_ipaddr, MDL); host_dereference (&p, MDL); if (n) { host_reference (&p, n, MDL); host_dereference (&n, MDL); } } } /* If we find an abandoned lease, but it's the one the client requested, we assume that previous bugginess on the part of the client, or a server database loss, caused the lease to be abandoned, so we reclaim it and let the client have it. */ if (lease && (lease -> binding_state == FTS_ABANDONED) && lease == ip_lease && packet -> packet_type == DHCPREQUEST) { log_error ("Reclaiming REQUESTed abandoned IP address %s.", piaddr (lease -> ip_addr)); } else if (lease && (lease -> binding_state == FTS_ABANDONED)) { /* Otherwise, if it's not the one the client requested, we do not return it - instead, we claim it's ours, causing a DHCPNAK to be sent if this lookup is for a DHCPREQUEST, and force the client to go back through the allocation process. */ if (ours) *ours = 1; lease_dereference (&lease, MDL); } out: if (have_client_identifier) data_string_forget (&client_identifier, MDL); if (fixed_lease) lease_dereference (&fixed_lease, MDL); if (hw_lease) lease_dereference (&hw_lease, MDL); if (uid_lease) lease_dereference (&uid_lease, MDL); if (ip_lease) lease_dereference (&ip_lease, MDL); if (host) host_dereference (&host, MDL); if (lease) { #if defined (DEBUG_FIND_LEASE) log_info ("Returning lease: %s.", piaddr (lease -> ip_addr)); #endif lease_reference (lp, lease, file, line); lease_dereference (&lease, MDL); return 1; } #if defined (DEBUG_FIND_LEASE) log_info ("Not returning a lease."); #endif return 0; } /* Search the provided host_decl structure list for an address that's on the specified shared network. If one is found, mock up and return a lease structure for it; otherwise return the null pointer. */ int mockup_lease (struct lease **lp, struct packet *packet, struct shared_network *share, struct host_decl *hp) { struct lease *lease = (struct lease *)0; struct host_decl *rhp = (struct host_decl *)0; if (lease_allocate (&lease, MDL) != ISC_R_SUCCESS) return 0; if (host_reference (&rhp, hp, MDL) != ISC_R_SUCCESS) { lease_dereference (&lease, MDL); return 0; } if (!find_host_for_network (&lease -> subnet, &rhp, &lease -> ip_addr, share)) { lease_dereference (&lease, MDL); host_dereference (&rhp, MDL); return 0; } host_reference (&lease -> host, rhp, MDL); if (rhp -> client_identifier.len > sizeof lease -> uid_buf) lease -> uid = dmalloc (rhp -> client_identifier.len, MDL); else lease -> uid = lease -> uid_buf; if (!lease -> uid) { lease_dereference (&lease, MDL); host_dereference (&rhp, MDL); return 0; } memcpy (lease -> uid, rhp -> client_identifier.data, rhp -> client_identifier.len); lease -> uid_len = rhp -> client_identifier.len; lease -> hardware_addr = rhp -> interface; lease -> starts = lease -> timestamp = lease -> ends = MIN_TIME; lease -> flags = STATIC_LEASE; lease -> binding_state = FTS_FREE; lease_reference (lp, lease, MDL); lease_dereference (&lease, MDL); host_dereference (&rhp, MDL); return 1; } /* Look through all the pools in a list starting with the specified pool for a free lease. We try to find a virgin lease if we can. If we don't find a virgin lease, we try to find a non-virgin lease that's free. If we can't find one of those, we try to reclaim an abandoned lease. If all of these possibilities fail to pan out, we don't return a lease at all. */ int allocate_lease (struct lease **lp, struct packet *packet, struct pool *pool, int *peer_has_leases) { struct lease *lease = (struct lease *)0; struct lease *candl = (struct lease *)0; for (; pool ; pool = pool -> next) { if ((pool -> prohibit_list && permitted (packet, pool -> prohibit_list)) || (pool -> permit_list && !permitted (packet, pool -> permit_list))) continue; #if defined (FAILOVER_PROTOCOL) /* Peer_has_leases just says that we found at least one free lease. If no free lease is returned, the caller can deduce that this means the peer is hogging all the free leases, so we can print a better error message. */ /* XXX Do we need code here to ignore PEER_IS_OWNER and * XXX just check tstp if we're in, e.g., PARTNER_DOWN? * XXX Where do we deal with CONFLICT_DETECTED, et al? */ /* XXX This should be handled by the lease binding "state * XXX machine" - that is, when we get here, if a lease * XXX could be allocated, it will have the correct * XXX binding state so that the following code will * XXX result in its being allocated. */ /* Skip to the most expired lease in the pool that is not * owned by a failover peer. */ if (pool -> failover_peer) { if (pool -> failover_peer -> i_am == primary) { if (pool -> backup) *peer_has_leases = 1; candl = pool -> free; if (!candl) candl = pool -> abandoned; } else { if (pool -> free) *peer_has_leases = 1; candl = pool -> backup; } } else #endif { if (pool -> free) candl = pool -> free; else candl = pool -> abandoned; } if (!candl || (candl -> ends > cur_time)) continue; if (!lease) { lease = candl; continue; } if ((lease -> binding_state == FTS_ABANDONED) && ((candl -> binding_state != FTS_ABANDONED) || (candl -> ends < lease -> ends))) { lease = candl; continue; } else if (candl -> binding_state == FTS_ABANDONED) continue; if ((lease -> uid_len || lease -> hardware_addr.hlen) && ((!candl -> uid_len && !candl -> hardware_addr.hlen) || (candl -> ends < lease -> ends))) { lease = candl; continue; } else if (candl -> uid_len || candl -> hardware_addr.hlen) continue; if (candl -> ends < lease -> ends) lease = candl; } if (lease) { if (lease -> binding_state == FTS_ABANDONED) log_error ("Reclaiming abandoned lease %s.", piaddr (lease -> ip_addr)); lease_reference (lp, lease, MDL); return 1; } return 0; } /* Determine whether or not a permit exists on a particular permit list that matches the specified packet, returning nonzero if so, zero if not. */ int permitted (packet, permit_list) struct packet *packet; struct permit *permit_list; { struct permit *p; int i; for (p = permit_list; p; p = p -> next) { switch (p -> type) { case permit_unknown_clients: if (!packet -> known) return 1; break; case permit_known_clients: if (packet -> known) return 1; break; case permit_authenticated_clients: if (packet -> authenticated) return 1; break; case permit_unauthenticated_clients: if (!packet -> authenticated) return 1; break; case permit_all_clients: return 1; case permit_dynamic_bootp_clients: if (!packet -> options_valid || !packet -> packet_type) return 1; break; case permit_class: for (i = 0; i < packet -> class_count; i++) { if (p -> class == packet -> classes [i]) return 1; if (packet -> classes [i] && packet -> classes [i] -> superclass && (packet -> classes [i] -> superclass == p -> class)) return 1; } break; } } return 0; } int locate_network (packet) struct packet *packet; { struct iaddr ia; struct data_string data; struct subnet *subnet = (struct subnet *)0; struct option_cache *oc; /* See if there's a subnet selection option. */ oc = lookup_option (&dhcp_universe, packet -> options, DHO_SUBNET_SELECTION); /* If there's no SSO and no giaddr, then use the shared_network from the interface, if there is one. If not, fail. */ if (!oc && !packet -> raw -> giaddr.s_addr) { if (packet -> interface -> shared_network) { shared_network_reference (&packet -> shared_network, packet -> interface -> shared_network, MDL); return 1; } return 0; } /* If there's an SSO, and it's valid, use it to figure out the subnet. If it's not valid, fail. */ if (oc) { memset (&data, 0, sizeof data); if (!evaluate_option_cache (&data, packet, (struct lease *)0, (struct client_state *)0, packet -> options, (struct option_state *)0, &global_scope, oc, MDL)) { return 0; } if (data.len != 4) { return 0; } ia.len = 4; memcpy (ia.iabuf, data.data, 4); data_string_forget (&data, MDL); } else { ia.len = 4; memcpy (ia.iabuf, &packet -> raw -> giaddr, 4); } /* If we know the subnet on which the IP address lives, use it. */ if (find_subnet (&subnet, ia, MDL)) { shared_network_reference (&packet -> shared_network, subnet -> shared_network, MDL); subnet_dereference (&subnet, MDL); return 1; } /* Otherwise, fail. */ return 0; }