bootp.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdarg.h>
#include <sys/types.h>
#include <errno.h>
#include <assert.h>
#include <string.h>
#include <syslog.h>
#include <sys/socket.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <arpa/inet.h>
#include <nss_dbdefs.h>
#include <netinet/dhcp.h>
#include <netdb.h>
#include <dhcp_symbol.h>
#include "dhcpd.h"
#include "per_dnet.h"
#include "interfaces.h"
#include <locale.h>
/*
* This file contains the code which implements the BOOTP compatibility.
*/
/*
* We are guaranteed that the packet received is a BOOTP request packet,
* e.g., *NOT* a DHCP packet.
*/
void
bootp(dsvc_clnt_t *pcd, PKT_LIST *plp)
{
boolean_t result, existing_offer = B_FALSE;
int err, write_error = DSVC_SUCCESS, flags = 0;
int pkt_len;
uint_t crecords = 0, irecords = 0, srecords = 0, clen;
uint32_t query;
PKT *rep_pktp = NULL;
IF *ifp = pcd->ifp;
dsvc_dnet_t *pnd = pcd->pnd;
uchar_t *optp;
dn_rec_t dn, ndn, *dnp;
dn_rec_list_t *dncp = NULL, *dnip = NULL, *dnlp = NULL;
struct in_addr ciaddr;
struct in_addr no_ip; /* network order IP */
ENCODE *ecp, *hecp;
MACRO *mp, *nmp, *cmp;
time_t now = time(NULL);
DHCP_MSG_CATEGORIES log;
struct hostent h, *hp;
char ntoab[INET_ADDRSTRLEN], cipbuf[INET_ADDRSTRLEN];
char cidbuf[DHCP_MAX_OPT_SIZE];
char hbuf[NSS_BUFLEN_HOSTS];
#ifdef DEBUG
dhcpmsg(LOG_DEBUG, "BOOTP request received on %s\n", ifp->nm);
#endif /* DEBUG */
if (pcd->off_ip.s_addr != htonl(INADDR_ANY) &&
PCD_OFFER_TIMEOUT(pcd, now))
purge_offer(pcd, B_TRUE, B_TRUE);
if (pcd->off_ip.s_addr != htonl(INADDR_ANY)) {
existing_offer = B_TRUE;
dnlp = pcd->dnlp;
assert(dnlp != NULL);
dnp = dnlp->dnl_rec;
no_ip.s_addr = htonl(dnp->dn_cip.s_addr);
crecords = 1;
} else {
/*
* Try to find a CID entry for the client. We don't care about
* lease info here, since a BOOTP client always has a permanent
* lease. We also don't care about the entry owner either,
* unless we end up allocating a new entry for the client.
*/
DSVC_QINIT(query);
DSVC_QEQ(query, DN_QCID);
(void) memcpy(dn.dn_cid, pcd->cid, pcd->cid_len);
dn.dn_cid_len = pcd->cid_len;
DSVC_QEQ(query, DN_QFBOOTP_ONLY);
dn.dn_flags = DN_FBOOTP_ONLY;
/*
* If a client address (ciaddr) is given, we simply trust that
* the client knows what it's doing, and we use that IP address
* to locate the client's record. If we can't find the client's
* record, then we keep silent. If the client id of the record
* doesn't match this client, then either the client or our
* database is inconsistent, and we'll ignore it (notice
* message generated).
*/
ciaddr.s_addr = plp->pkt->ciaddr.s_addr;
if (ciaddr.s_addr != htonl(INADDR_ANY)) {
DSVC_QEQ(query, DN_QCIP);
dn.dn_cip.s_addr = ntohl(ciaddr.s_addr);
}
dnlp = dhcp_lookup_dd_classify(pcd->pnd, B_FALSE, query,
-1, &dn, (void **)&dncp, S_CID);
if (dnlp != NULL) {
crecords = 1;
dnp = dnlp->dnl_rec;
if (dnp->dn_flags & DN_FUNUSABLE)
goto leave_bootp;
no_ip.s_addr = htonl(dnp->dn_cip.s_addr);
}
}
(void) inet_ntop(AF_INET, &no_ip, cipbuf, sizeof (cipbuf));
if (crecords == 0 && !be_automatic) {
if (verbose) {
dhcpmsg(LOG_INFO, "BOOTP client: %1$s is looking for "
"a configuration on net %2$s\n", pcd->cidbuf,
pnd->network);
}
goto leave_bootp;
}
/*
* If the client thinks it knows who it is (ciaddr), and this doesn't
* match our registered IP address, then display an error message and
* give up.
*/
if (ciaddr.s_addr != htonl(INADDR_ANY) && crecords == 0) {
/*
* If the client specified an IP address, then let's check
* whether it is available, since we have no CID mapping
* registered for this client. If it is available and
* unassigned but owned by a different server, we ignore the
* client.
*/
DSVC_QINIT(query);
DSVC_QEQ(query, DN_QCIP);
dn.dn_cip.s_addr = ntohl(ciaddr.s_addr);
(void) inet_ntop(AF_INET, &ciaddr, cipbuf, sizeof (cipbuf));
DSVC_QEQ(query, DN_QFBOOTP_ONLY);
dn.dn_flags = DN_FBOOTP_ONLY;
dnip = NULL;
dnlp = dhcp_lookup_dd_classify(pcd->pnd, B_FALSE, query,
-1, &dn, (void **)&dncp, S_CID);
if (dnlp == NULL) {
/*
* We have no record of this client's IP address, thus
* we really can't respond to this client, because it
* doesn't have a configuration.
*/
if (verbose) {
dhcpmsg(LOG_INFO, "No configuration for BOOTP "
"client: %1$s. IP address: %2$s not "
"administered by this server.\n",
pcd->cidbuf, inet_ntop(AF_INET, &ciaddr,
ntoab, sizeof (ntoab)));
}
goto leave_bootp;
} else
irecords = 1;
dnp = dnlp->dnl_rec;
if (dnp->dn_flags & DN_FUNUSABLE)
goto leave_bootp;
if (dn.dn_cid_len != 0) {
if (dn.dn_cid_len != pcd->cid_len || memcmp(dn.dn_cid,
pcd->cid, pcd->cid_len) != 0) {
if (verbose) {
clen = sizeof (cidbuf);
(void) octet_to_hexascii(dn.dn_cid,
dn.dn_cid_len, cidbuf, &clen);
dhcpmsg(LOG_INFO, "BOOTP client: %1$s "
"thinks it owns %2$s, but that "
"address belongs to %3$s. Ignoring "
"client.\n", pcd->cidbuf, cipbuf,
cidbuf);
}
goto leave_bootp;
}
} else {
if (match_ownerip(htonl(dn.dn_sip.s_addr)) == NULL) {
if (verbose) {
no_ip.s_addr =
htonl(dnp->dn_sip.s_addr);
dhcpmsg(LOG_INFO, "BOOTP client: %1$s "
"believes it owns %2$s. That "
"address is free, but is owned by "
"DHCP server %3$s. Ignoring "
"client.\n", pcd->cidbuf, cipbuf,
inet_ntop(AF_INET, &no_ip, ntoab,
sizeof (ntoab)));
}
goto leave_bootp;
}
}
no_ip.s_addr = htonl(dnp->dn_cip.s_addr);
(void) inet_ntop(AF_INET, &no_ip, cipbuf, sizeof (cipbuf));
}
if (crecords == 0) {
/*
* The dhcp-network table did not have any matching entries.
* Try to allocate a new one if possible.
*/
if (irecords == 0 && select_offer(pnd, plp, pcd, &dnlp)) {
dnp = dnlp->dnl_rec;
no_ip.s_addr = htonl(dnp->dn_cip.s_addr);
(void) inet_ntop(AF_INET, &no_ip, cipbuf,
sizeof (cipbuf));
srecords = 1;
}
}
if (crecords == 0 && irecords == 0 && srecords == 0) {
dhcpmsg(LOG_NOTICE,
"(%1$s) No more BOOTP IP addresses for %2$s network.\n",
pcd->cidbuf, pnd->network);
goto leave_bootp;
}
/* Check the address. But only if client doesn't know its address. */
ndn = *dnp; /* struct copy */
no_ip.s_addr = htonl(ndn.dn_cip.s_addr);
(void) inet_ntop(AF_INET, &no_ip, cipbuf, sizeof (cipbuf));
if (ciaddr.s_addr == htonl(INADDR_ANY)) {
if ((ifp->flags & IFF_NOARP) == 0)
(void) set_arp(ifp, &no_ip, NULL, 0, DHCP_ARP_DEL);
if (!noping) {
/*
* If icmp echo check fails,
* let the plp fall by the wayside.
*/
errno = icmp_echo_check(&no_ip, &result);
if (errno != 0) {
dhcpmsg(LOG_ERR, "ICMP ECHO check cannot be "
"performed for: %s, ignoring\n", cipbuf);
goto leave_bootp;
}
if (result) {
dhcpmsg(LOG_ERR, "ICMP ECHO reply to BOOTP "
"OFFER candidate: %s, disabling.\n",
cipbuf);
ndn.dn_flags |= DN_FUNUSABLE;
if ((err = dhcp_modify_dd_entry(pnd->dh,
dnp, &ndn)) == DSVC_SUCCESS) {
/* Keep the cached entry current. */
*dnp = ndn; /* struct copy */
}
logtrans(P_BOOTP, L_ICMP_ECHO, 0, no_ip,
server_ip, plp);
goto leave_bootp;
}
}
}
/*
* It is possible that the client could specify a REQUEST list,
* but then it would be a DHCP client, wouldn't it? Only copy the
* std option list, since that potentially could be changed by
* load_options().
*/
ecp = NULL;
if (!no_dhcptab) {
open_macros();
if ((nmp = get_macro(pnd->network)) != NULL)
ecp = dup_encode_list(nmp->head);
if ((mp = get_macro(dnp->dn_macro)) != NULL)
ecp = combine_encodes(ecp, mp->head, ENC_DONT_COPY);
if ((cmp = get_macro(pcd->cidbuf)) != NULL)
ecp = combine_encodes(ecp, cmp->head, ENC_DONT_COPY);
/* If dhcptab configured to return hostname, do so. */
if (find_encode(ecp, DSYM_INTERNAL, CD_BOOL_HOSTNAME) !=
NULL) {
hp = gethostbyaddr_r((char *)&ndn.dn_cip,
sizeof (struct in_addr), AF_INET, &h, hbuf,
sizeof (hbuf), &err);
if (hp != NULL) {
hecp = make_encode(DSYM_STANDARD,
CD_HOSTNAME, strlen(hp->h_name),
hp->h_name, ENC_COPY);
replace_encode(&ecp, hecp, ENC_DONT_COPY);
}
}
}
/* Produce a BOOTP reply. */
rep_pktp = gen_bootp_pkt(sizeof (PKT), plp->pkt);
rep_pktp->op = BOOTREPLY;
optp = rep_pktp->options;
/*
* Set the client's "your" IP address if client doesn't know it,
* otherwise echo the client's ciaddr back to him.
*/
if (ciaddr.s_addr == htonl(INADDR_ANY))
rep_pktp->yiaddr.s_addr = htonl(ndn.dn_cip.s_addr);
else
rep_pktp->ciaddr.s_addr = ciaddr.s_addr;
/*
* Omit lease time options implicitly, e.g.
* ~(DHCP_DHCP_CLNT | DHCP_SEND_LEASE)
*/
if (!plp->rfc1048)
flags |= DHCP_NON_RFC1048;
/* Now load in configured options. */
pkt_len = load_options(flags, plp, rep_pktp, sizeof (PKT), optp, ecp,
NULL);
free_encode_list(ecp);
if (!no_dhcptab)
close_macros();
if (pkt_len < sizeof (PKT))
pkt_len = sizeof (PKT);
/*
* Only perform a write if we have selected an entry not yet
* assigned to the client (a matching DN_FBOOTP_ONLY entry from
* ip address lookup, or an unassigned entry from select_offer()).
*/
if (srecords > 0 || irecords > 0) {
(void) memcpy(&ndn.dn_cid, pcd->cid, pcd->cid_len);
ndn.dn_cid_len = pcd->cid_len;
write_error = dhcp_modify_dd_entry(pnd->dh, dnp, &ndn);
/* Keep state of the cached entry current. */
*dnp = ndn; /* struct copy */
log = L_ASSIGN;
} else {
if (verbose) {
dhcpmsg(LOG_INFO, "Database write unnecessary for "
"BOOTP client: %1$s, %2$s\n",
pcd->cidbuf, cipbuf);
}
log = L_REPLY;
}
if (write_error == DSVC_SUCCESS) {
if (send_reply(ifp, rep_pktp, pkt_len, &no_ip) != 0) {
dhcpmsg(LOG_ERR,
"Reply to BOOTP client %1$s with %2$s failed.\n",
pcd->cidbuf, cipbuf);
} else {
/* Note that the conversation has completed. */
pcd->state = ACK;
(void) update_offer(pcd, dnlp, 0, &no_ip, B_TRUE);
existing_offer = B_TRUE;
}
logtrans(P_BOOTP, log, ndn.dn_lease, no_ip, server_ip, plp);
}
leave_bootp:
if (rep_pktp != NULL)
free(rep_pktp);
if (dncp != NULL)
dhcp_free_dd_list(pnd->dh, dncp);
if (dnip != NULL)
dhcp_free_dd_list(pnd->dh, dnip);
if (dnlp != NULL && !existing_offer)
dhcp_free_dd_list(pnd->dh, dnlp);
}