/* * Copyright (c) 1988, 1992 The University of Utah and the Center *	for Software Science (CSS). * Copyright (c) 1992, 1993 *	The Regents of the University of California.  All rights reserved. * * This code is derived from software contributed to Berkeley by * the Center for Software Science of the University of Utah Computer * Science Department.  CSS requests users of this software to return * to css-dist@cs.utah.edu any improvements that they make and grant * CSS redistribution rights. * * 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, Berkeley 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. * *	@(#)bpf.c	8.1 (Berkeley) 6/4/93 * * Utah $Hdr: bpf.c 3.1 92/07/06$ * Author: Jeff Forys, University of Utah CSS */#ifndef lintstatic char sccsid[] = "@(#)bpf.c	8.1 (Berkeley) 6/4/93";#endif /* not lint */#include <sys/param.h>#include <sys/ioctl.h>#include <sys/socket.h>#include <net/if.h>#include <net/bpf.h>#include <ctype.h>#include <errno.h>#include <fcntl.h>#include <stdio.h>#include <stdlib.h>#include <string.h>#include <syslog.h>#include <unistd.h>#include "defs.h"#include "pathnames.h"static int BpfFd = -1;static unsigned BpfLen = 0;static u_char *BpfPkt = NULL;/***  BpfOpen -- Open and initialize a BPF device.****	Parameters:**		None.****	Returns:**		File descriptor of opened BPF device (for select() etc).****	Side Effects:**		If an error is encountered, the program terminates here.*/intBpfOpen(){	struct ifreq ifr;	char bpfdev[32];	int n = 0;	/*	 *  Open the first available BPF device.	 */	do {		(void) sprintf(bpfdev, _PATH_BPF, n++);		BpfFd = open(bpfdev, O_RDWR);	} while (BpfFd < 0 && (errno == EBUSY || errno == EPERM));	if (BpfFd < 0) {		syslog(LOG_ERR, "bpf: no available devices: %m");		Exit(0);	}	/*	 *  Set interface name for bpf device, get data link layer	 *  type and make sure it's type Ethernet.	 */	(void) strncpy(ifr.ifr_name, IntfName, sizeof(ifr.ifr_name));	if (ioctl(BpfFd, BIOCSETIF, (caddr_t)&ifr) < 0) {		syslog(LOG_ERR, "bpf: ioctl(BIOCSETIF,%s): %m", IntfName);		Exit(0);	}	/*	 *  Make sure we are dealing with an Ethernet device.	 */	if (ioctl(BpfFd, BIOCGDLT, (caddr_t)&n) < 0) {		syslog(LOG_ERR, "bpf: ioctl(BIOCGDLT): %m");		Exit(0);	}	if (n != DLT_EN10MB) {		syslog(LOG_ERR,"bpf: %s: data-link type %d unsupported",		       IntfName, n);		Exit(0);	}	/*	 *  On read(), return packets immediately (do not buffer them).	 */	n = 1;	if (ioctl(BpfFd, BIOCIMMEDIATE, (caddr_t)&n) < 0) {		syslog(LOG_ERR, "bpf: ioctl(BIOCIMMEDIATE): %m");		Exit(0);	}	/*	 *  Try to enable the chip/driver's multicast address filter to	 *  grab our RMP address.  If this fails, try promiscuous mode.	 *  If this fails, there's no way we are going to get any RMP	 *  packets so just exit here.	 */#ifdef MSG_EOR	ifr.ifr_addr.sa_len = RMP_ADDRLEN + 2;#endif	ifr.ifr_addr.sa_family = AF_UNSPEC;	bcopy(&RmpMcastAddr[0], (char *)&ifr.ifr_addr.sa_data[0], RMP_ADDRLEN);	if (ioctl(BpfFd, SIOCADDMULTI, (caddr_t)&ifr) < 0) {		syslog(LOG_WARNING,		    "bpf: can't add mcast addr (%m), setting promiscuous mode");		if (ioctl(BpfFd, BIOCPROMISC, (caddr_t)0) < 0) {			syslog(LOG_ERR, "bpf: can't set promiscuous mode: %m");			Exit(0);		}	}	/*	 *  Ask BPF how much buffer space it requires and allocate one.	 */	if (ioctl(BpfFd, BIOCGBLEN, (caddr_t)&BpfLen) < 0) {		syslog(LOG_ERR, "bpf: ioctl(BIOCGBLEN): %m");		Exit(0);	}	if (BpfPkt == NULL)		BpfPkt = (u_char *)malloc(BpfLen);	if (BpfPkt == NULL) {		syslog(LOG_ERR, "bpf: out of memory (%u bytes for bpfpkt)",		       BpfLen);		Exit(0);	}	/*	 *  Write a little program to snarf RMP Boot packets and stuff	 *  it down BPF's throat (i.e. set up the packet filter).	 */	{#define	RMP	((struct rmp_packet *)0)		static struct bpf_insn bpf_insn[] = {		    { BPF_LD|BPF_B|BPF_ABS,  0, 0, (long)&RMP->hp_llc.dsap },		    { BPF_JMP|BPF_JEQ|BPF_K, 0, 5, IEEE_DSAP_HP },		    { BPF_LD|BPF_H|BPF_ABS,  0, 0, (long)&RMP->hp_llc.cntrl },		    { BPF_JMP|BPF_JEQ|BPF_K, 0, 3, IEEE_CNTL_HP },		    { BPF_LD|BPF_H|BPF_ABS,  0, 0, (long)&RMP->hp_llc.dxsap },		    { BPF_JMP|BPF_JEQ|BPF_K, 0, 1, HPEXT_DXSAP },		    { BPF_RET|BPF_K,         0, 0, RMP_MAX_PACKET },		    { BPF_RET|BPF_K,         0, 0, 0x0 }		};#undef	RMP		static struct bpf_program bpf_pgm = {		    sizeof(bpf_insn)/sizeof(bpf_insn[0]), bpf_insn		};		if (ioctl(BpfFd, BIOCSETF, (caddr_t)&bpf_pgm) < 0) {			syslog(LOG_ERR, "bpf: ioctl(BIOCSETF): %m");			Exit(0);		}	}	return(BpfFd);}/***  BPF GetIntfName -- Return the name of a network interface attached to**		the system, or 0 if none can be found.  The interface**		must be configured up; the lowest unit number is**		preferred; loopback is ignored.****	Parameters:**		errmsg - if no network interface found, *errmsg explains why.****	Returns:**		A (static) pointer to interface name, or NULL on error.****	Side Effects:**		None.*/char *BpfGetIntfName(errmsg)	char **errmsg;{	struct ifreq ibuf[8], *ifrp, *ifend, *mp;	struct ifconf ifc;	int fd;	int minunit, n;	char *cp;	static char device[sizeof(ifrp->ifr_name)];	static char errbuf[128] = "No Error!";	if (errmsg != NULL)		*errmsg = errbuf;	if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {		(void) strcpy(errbuf, "bpf: socket: %m");		return(NULL);	}	ifc.ifc_len = sizeof ibuf;	ifc.ifc_buf = (caddr_t)ibuf;#ifdef OSIOCGIFCONF	if (ioctl(fd, OSIOCGIFCONF, (char *)&ifc) < 0 ||	    ifc.ifc_len < sizeof(struct ifreq)) {		(void) strcpy(errbuf, "bpf: ioctl(OSIOCGIFCONF): %m");		return(NULL);	}#else	if (ioctl(fd, SIOCGIFCONF, (char *)&ifc) < 0 ||	    ifc.ifc_len < sizeof(struct ifreq)) {		(void) strcpy(errbuf, "bpf: ioctl(SIOCGIFCONF): %m");		return(NULL);	}#endif	ifrp = ibuf;	ifend = (struct ifreq *)((char *)ibuf + ifc.ifc_len);		mp = 0;	minunit = 666;	for (; ifrp < ifend; ++ifrp) {		if (ioctl(fd, SIOCGIFFLAGS, (char *)ifrp) < 0) {			(void) strcpy(errbuf, "bpf: ioctl(SIOCGIFFLAGS): %m");			return(NULL);		}		/*		 *  If interface is down or this is the loopback interface,		 *  ignore it.		 */		if ((ifrp->ifr_flags & IFF_UP) == 0 ||#ifdef IFF_LOOPBACK		    (ifrp->ifr_flags & IFF_LOOPBACK))#else		    (strcmp(ifrp->ifr_name, "lo0") == 0))#endif			continue;		for (cp = ifrp->ifr_name; !isdigit(*cp); ++cp)			;		n = atoi(cp);		if (n < minunit) {			minunit = n;			mp = ifrp;		}	}	(void) close(fd);	if (mp == 0) {		(void) strcpy(errbuf, "bpf: no interfaces found");		return(NULL);	}	(void) strcpy(device, mp->ifr_name);	return(device);}/***  BpfRead -- Read packets from a BPF device and fill in `rconn'.****	Parameters:**		rconn - filled in with next packet.**		doread - is True if we can issue a read() syscall.****	Returns:**		True if `rconn' contains a new packet, False otherwise.****	Side Effects:**		None.*/intBpfRead(rconn, doread)	RMPCONN *rconn;	int doread;{	register int datlen, caplen, hdrlen;	static u_char *bp = NULL, *ep = NULL;	int cc;	/*	 *  The read() may block, or it may return one or more packets.	 *  We let the caller decide whether or not we can issue a read().	 */	if (doread) {		if ((cc = read(BpfFd, (char *)BpfPkt, (int)BpfLen)) < 0) {			syslog(LOG_ERR, "bpf: read: %m");			return(0);		} else {			bp = BpfPkt;			ep = BpfPkt + cc;		}	}#define bhp ((struct bpf_hdr *)bp)	/*	 *  If there is a new packet in the buffer, stuff it into `rconn'	 *  and return a success indication.	 */	if (bp < ep) {		datlen = bhp->bh_datalen;		caplen = bhp->bh_caplen;		hdrlen = bhp->bh_hdrlen;		if (caplen != datlen)			syslog(LOG_ERR,			       "bpf: short packet dropped (%d of %d bytes)",			       caplen, datlen);		else if (caplen > sizeof(struct rmp_packet))			syslog(LOG_ERR, "bpf: large packet dropped (%d bytes)",			       caplen);		else {			rconn->rmplen = caplen;			bcopy((char *)&bhp->bh_tstamp, (char *)&rconn->tstamp,			      sizeof(struct timeval));			bcopy((char *)bp + hdrlen, (char *)&rconn->rmp, caplen);		}		bp += BPF_WORDALIGN(caplen + hdrlen);		return(1);	}#undef bhp	return(0);}/***  BpfWrite -- Write packet to BPF device.****	Parameters:**		rconn - packet to send.****	Returns:**		True if write succeeded, False otherwise.****	Side Effects:**		None.*/intBpfWrite(rconn)	RMPCONN *rconn;{	if (write(BpfFd, (char *)&rconn->rmp, rconn->rmplen) < 0) {		syslog(LOG_ERR, "write: %s: %m", EnetStr(rconn));		return(0);	}	return(1);}/***  BpfClose -- Close a BPF device.****	Parameters:**		None.****	Returns:**		Nothing.****	Side Effects:**		None.*/voidBpfClose(){	struct ifreq ifr;	if (BpfPkt != NULL) {		free((char *)BpfPkt);		BpfPkt = NULL;	}	if (BpfFd == -1)		return;#ifdef MSG_EOR	ifr.ifr_addr.sa_len = RMP_ADDRLEN + 2;#endif	ifr.ifr_addr.sa_family = AF_UNSPEC;	bcopy(&RmpMcastAddr[0], (char *)&ifr.ifr_addr.sa_data[0], RMP_ADDRLEN);	if (ioctl(BpfFd, SIOCDELMULTI, (caddr_t)&ifr) < 0)		(void) ioctl(BpfFd, BIOCPROMISC, (caddr_t)0);	(void) close(BpfFd);	BpfFd = -1;}