FreeBSD-5.3/lib/libstand/bootp.c
/* $NetBSD: bootp.c,v 1.14 1998/02/16 11:10:54 drochner Exp $ */
/*
* Copyright (c) 1992 Regents of the University of California.
* All rights reserved.
*
* This software was developed by the Computer Systems Engineering group
* at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
* contributed to Berkeley.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Lawrence Berkeley Laboratory and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#) Header: bootp.c,v 1.4 93/09/11 03:13:51 leres Exp (LBL)
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/lib/libstand/bootp.c,v 1.5 2002/03/21 23:38:48 obrien Exp $");
#include <sys/types.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <string.h>
#define BOOTP_DEBUGxx
#define SUPPORT_DHCP
#include "stand.h"
#include "net.h"
#include "netif.h"
#include "bootp.h"
struct in_addr servip;
static n_long nmask, smask;
static time_t bot;
static char vm_rfc1048[4] = VM_RFC1048;
#ifdef BOOTP_VEND_CMU
static char vm_cmu[4] = VM_CMU;
#endif
/* Local forwards */
static ssize_t bootpsend(struct iodesc *, void *, size_t);
static ssize_t bootprecv(struct iodesc *, void *, size_t, time_t);
static int vend_rfc1048(u_char *, u_int);
#ifdef BOOTP_VEND_CMU
static void vend_cmu(u_char *);
#endif
#ifdef SUPPORT_DHCP
static char expected_dhcpmsgtype = -1, dhcp_ok;
struct in_addr dhcp_serverip;
#endif
/* Fetch required bootp infomation */
void
bootp(sock, flag)
int sock;
int flag;
{
struct iodesc *d;
struct bootp *bp;
struct {
u_char header[HEADER_SIZE];
struct bootp wbootp;
} wbuf;
struct {
u_char header[HEADER_SIZE];
struct bootp rbootp;
} rbuf;
#ifdef BOOTP_DEBUG
if (debug)
printf("bootp: socket=%d\n", sock);
#endif
if (!bot)
bot = getsecs();
if (!(d = socktodesc(sock))) {
printf("bootp: bad socket. %d\n", sock);
return;
}
#ifdef BOOTP_DEBUG
if (debug)
printf("bootp: d=%lx\n", (long)d);
#endif
bp = &wbuf.wbootp;
bzero(bp, sizeof(*bp));
bp->bp_op = BOOTREQUEST;
bp->bp_htype = 1; /* 10Mb Ethernet (48 bits) */
bp->bp_hlen = 6;
bp->bp_xid = htonl(d->xid);
MACPY(d->myea, bp->bp_chaddr);
strncpy(bp->bp_file, bootfile, sizeof(bp->bp_file));
bcopy(vm_rfc1048, bp->bp_vend, sizeof(vm_rfc1048));
#ifdef SUPPORT_DHCP
bp->bp_vend[4] = TAG_DHCP_MSGTYPE;
bp->bp_vend[5] = 1;
bp->bp_vend[6] = DHCPDISCOVER;
/*
* If we are booting from PXE, we want to send the string
* 'PXEClient' to the DHCP server so you have the option of
* only responding to PXE aware dhcp requests.
*/
if (flag & BOOTP_PXE) {
bp->bp_vend[7] = TAG_CLASSID;
bp->bp_vend[8] = 9;
bcopy("PXEClient", &bp->bp_vend[9], 9);
bp->bp_vend[18] = TAG_END;
} else
bp->bp_vend[7] = TAG_END;
#else
bp->bp_vend[4] = TAG_END;
#endif
d->myip.s_addr = INADDR_ANY;
d->myport = htons(IPPORT_BOOTPC);
d->destip.s_addr = INADDR_BROADCAST;
d->destport = htons(IPPORT_BOOTPS);
#ifdef SUPPORT_DHCP
expected_dhcpmsgtype = DHCPOFFER;
dhcp_ok = 0;
#endif
if(sendrecv(d,
bootpsend, bp, sizeof(*bp),
bootprecv, &rbuf.rbootp, sizeof(rbuf.rbootp))
== -1) {
printf("bootp: no reply\n");
return;
}
#ifdef SUPPORT_DHCP
if(dhcp_ok) {
u_int32_t leasetime;
bp->bp_vend[6] = DHCPREQUEST;
bp->bp_vend[7] = TAG_REQ_ADDR;
bp->bp_vend[8] = 4;
bcopy(&rbuf.rbootp.bp_yiaddr, &bp->bp_vend[9], 4);
bp->bp_vend[13] = TAG_SERVERID;
bp->bp_vend[14] = 4;
bcopy(&dhcp_serverip.s_addr, &bp->bp_vend[15], 4);
bp->bp_vend[19] = TAG_LEASETIME;
bp->bp_vend[20] = 4;
leasetime = htonl(300);
bcopy(&leasetime, &bp->bp_vend[21], 4);
if (flag & BOOTP_PXE) {
bp->bp_vend[25] = TAG_CLASSID;
bp->bp_vend[26] = 9;
bcopy("PXEClient", &bp->bp_vend[27], 9);
bp->bp_vend[36] = TAG_END;
} else
bp->bp_vend[25] = TAG_END;
expected_dhcpmsgtype = DHCPACK;
if(sendrecv(d,
bootpsend, bp, sizeof(*bp),
bootprecv, &rbuf.rbootp, sizeof(rbuf.rbootp))
== -1) {
printf("DHCPREQUEST failed\n");
return;
}
}
#endif
myip = d->myip = rbuf.rbootp.bp_yiaddr;
servip = rbuf.rbootp.bp_siaddr;
if(rootip.s_addr == INADDR_ANY) rootip = servip;
bcopy(rbuf.rbootp.bp_file, bootfile, sizeof(bootfile));
bootfile[sizeof(bootfile) - 1] = '\0';
if (IN_CLASSA(ntohl(myip.s_addr)))
nmask = htonl(IN_CLASSA_NET);
else if (IN_CLASSB(ntohl(myip.s_addr)))
nmask = htonl(IN_CLASSB_NET);
else
nmask = htonl(IN_CLASSC_NET);
#ifdef BOOTP_DEBUG
if (debug)
printf("'native netmask' is %s\n", intoa(nmask));
#endif
/* Check subnet mask against net mask; toss if bogus */
if ((nmask & smask) != nmask) {
#ifdef BOOTP_DEBUG
if (debug)
printf("subnet mask (%s) bad\n", intoa(smask));
#endif
smask = 0;
}
/* Get subnet (or natural net) mask */
netmask = nmask;
if (smask)
netmask = smask;
#ifdef BOOTP_DEBUG
if (debug)
printf("mask: %s\n", intoa(netmask));
#endif
/* We need a gateway if root is on a different net */
if (!SAMENET(myip, rootip, netmask)) {
#ifdef BOOTP_DEBUG
if (debug)
printf("need gateway for root ip\n");
#endif
}
/* Toss gateway if on a different net */
if (!SAMENET(myip, gateip, netmask)) {
#ifdef BOOTP_DEBUG
if (debug)
printf("gateway ip (%s) bad\n", inet_ntoa(gateip));
#endif
gateip.s_addr = 0;
}
/* Bump xid so next request will be unique. */
++d->xid;
}
/* Transmit a bootp request */
static ssize_t
bootpsend(d, pkt, len)
struct iodesc *d;
void *pkt;
size_t len;
{
struct bootp *bp;
#ifdef BOOTP_DEBUG
if (debug)
printf("bootpsend: d=%lx called.\n", (long)d);
#endif
bp = pkt;
bp->bp_secs = htons((u_short)(getsecs() - bot));
#ifdef BOOTP_DEBUG
if (debug)
printf("bootpsend: calling sendudp\n");
#endif
return (sendudp(d, pkt, len));
}
static ssize_t
bootprecv(d, pkt, len, tleft)
struct iodesc *d;
void *pkt;
size_t len;
time_t tleft;
{
ssize_t n;
struct bootp *bp;
#ifdef BOOTP_DEBUGx
if (debug)
printf("bootp_recvoffer: called\n");
#endif
n = readudp(d, pkt, len, tleft);
if (n == -1 || n < sizeof(struct bootp) - BOOTP_VENDSIZE)
goto bad;
bp = (struct bootp *)pkt;
#ifdef BOOTP_DEBUG
if (debug)
printf("bootprecv: checked. bp = 0x%lx, n = %d\n",
(long)bp, (int)n);
#endif
if (bp->bp_xid != htonl(d->xid)) {
#ifdef BOOTP_DEBUG
if (debug) {
printf("bootprecv: expected xid 0x%lx, got 0x%x\n",
d->xid, ntohl(bp->bp_xid));
}
#endif
goto bad;
}
#ifdef BOOTP_DEBUG
if (debug)
printf("bootprecv: got one!\n");
#endif
/* Suck out vendor info */
if (bcmp(vm_rfc1048, bp->bp_vend, sizeof(vm_rfc1048)) == 0) {
if(vend_rfc1048(bp->bp_vend, sizeof(bp->bp_vend)) != 0)
goto bad;
}
#ifdef BOOTP_VEND_CMU
else if (bcmp(vm_cmu, bp->bp_vend, sizeof(vm_cmu)) == 0)
vend_cmu(bp->bp_vend);
#endif
else
printf("bootprecv: unknown vendor 0x%lx\n", (long)bp->bp_vend);
return(n);
bad:
errno = 0;
return (-1);
}
static int
vend_rfc1048(cp, len)
u_char *cp;
u_int len;
{
u_char *ep;
int size;
u_char tag;
#ifdef BOOTP_DEBUG
if (debug)
printf("vend_rfc1048 bootp info. len=%d\n", len);
#endif
ep = cp + len;
/* Step over magic cookie */
cp += sizeof(int);
while (cp < ep) {
tag = *cp++;
size = *cp++;
if (tag == TAG_END)
break;
if (tag == TAG_SUBNET_MASK) {
bcopy(cp, &smask, sizeof(smask));
}
if (tag == TAG_GATEWAY) {
bcopy(cp, &gateip.s_addr, sizeof(gateip.s_addr));
}
if (tag == TAG_SWAPSERVER) {
/* let it override bp_siaddr */
bcopy(cp, &rootip.s_addr, sizeof(swapip.s_addr));
}
if (tag == TAG_ROOTPATH) {
strncpy(rootpath, (char *)cp, sizeof(rootpath));
rootpath[size] = '\0';
}
if (tag == TAG_HOSTNAME) {
strncpy(hostname, (char *)cp, sizeof(hostname));
hostname[size] = '\0';
}
#ifdef SUPPORT_DHCP
if (tag == TAG_DHCP_MSGTYPE) {
if(*cp != expected_dhcpmsgtype)
return(-1);
dhcp_ok = 1;
}
if (tag == TAG_SERVERID) {
bcopy(cp, &dhcp_serverip.s_addr,
sizeof(dhcp_serverip.s_addr));
}
#endif
cp += size;
}
return(0);
}
#ifdef BOOTP_VEND_CMU
static void
vend_cmu(cp)
u_char *cp;
{
struct cmu_vend *vp;
#ifdef BOOTP_DEBUG
if (debug)
printf("vend_cmu bootp info.\n");
#endif
vp = (struct cmu_vend *)cp;
if (vp->v_smask.s_addr != 0) {
smask = vp->v_smask.s_addr;
}
if (vp->v_dgate.s_addr != 0) {
gateip = vp->v_dgate;
}
}
#endif