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    /*	$OpenBSD: bpf.c,v 1.26 2017/04/19 05:36:13 natano Exp $	*/  | 
    
    
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    /*	$NetBSD: bpf.c,v 1.5.2.1 1995/11/14 08:45:42 thorpej Exp $	*/  | 
    
    
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    /*  | 
    
    
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     * Copyright (c) 1988, 1992 The University of Utah and the Center  | 
    
    
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     *	for Software Science (CSS).  | 
    
    
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     * Copyright (c) 1992, 1993  | 
    
    
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     *	The Regents of the University of California.  All rights reserved.  | 
    
    
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     *  | 
    
    
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     * This code is derived from software contributed to Berkeley by  | 
    
    
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     * the Center for Software Science of the University of Utah Computer  | 
    
    
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     * Science Department.  CSS requests users of this software to return  | 
    
    
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     * to css-dist@cs.utah.edu any improvements that they make and grant  | 
    
    
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     * CSS redistribution rights.  | 
    
    
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     *  | 
    
    
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     * Redistribution and use in source and binary forms, with or without  | 
    
    
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     * modification, are permitted provided that the following conditions  | 
    
    
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     * are met:  | 
    
    
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     * 1. Redistributions of source code must retain the above copyright  | 
    
    
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     *    notice, this list of conditions and the following disclaimer.  | 
    
    
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     * 2. Redistributions in binary form must reproduce the above copyright  | 
    
    
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     *    notice, this list of conditions and the following disclaimer in the  | 
    
    
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     *    documentation and/or other materials provided with the distribution.  | 
    
    
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     * 3. Neither the name of the University nor the names of its contributors  | 
    
    
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     *    may be used to endorse or promote products derived from this software  | 
    
    
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     *    without specific prior written permission.  | 
    
    
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     *  | 
    
    
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     * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND  | 
    
    
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     * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE  | 
    
    
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     * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE  | 
    
    
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     * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE  | 
    
    
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     * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL  | 
    
    
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     * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS  | 
    
    
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     * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)  | 
    
    
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     * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT  | 
    
    
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     * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY  | 
    
    
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     * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF  | 
    
    
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     * SUCH DAMAGE.  | 
    
    
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     *  | 
    
    
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     *	from: @(#)bpf.c	8.1 (Berkeley) 6/4/93  | 
    
    
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     *  | 
    
    
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     * From: Utah Hdr: bpf.c 3.1 92/07/06  | 
    
    
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     * Author: Jeff Forys, University of Utah CSS  | 
    
    
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     */  | 
    
    
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    #include <sys/ioctl.h>  | 
    
    
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    #include <sys/socket.h>  | 
    
    
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    #include <net/if.h>  | 
    
    
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    #include <net/bpf.h>  | 
    
    
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    #include <ctype.h>  | 
    
    
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    #include <errno.h>  | 
    
    
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    #include <fcntl.h>  | 
    
    
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    #include <stddef.h>  | 
    
    
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    #include <stdio.h>  | 
    
    
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    #include <stdlib.h>  | 
    
    
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    #include <string.h>  | 
    
    
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    #include <syslog.h>  | 
    
    
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    #include <unistd.h>  | 
    
    
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    #include <limits.h>  | 
    
    
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    #include <ifaddrs.h>  | 
    
    
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    #include "defs.h"  | 
    
    
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    static int BpfFd = -1;  | 
    
    
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    static unsigned int BpfLen = 0;  | 
    
    
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    static u_int8_t *BpfPkt = NULL;  | 
    
    
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    /*  | 
    
    
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    **  BpfOpen -- Open and initialize a BPF device.  | 
    
    
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    **  | 
    
    
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    **	Parameters:  | 
    
    
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    **		None.  | 
    
    
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    **  | 
    
    
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    **	Returns:  | 
    
    
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    **		File descriptor of opened BPF device  | 
    
    
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    **  | 
    
    
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    **	Side Effects:  | 
    
    
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    **		If an error is encountered, the program terminates here.  | 
    
    
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    */  | 
    
    
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    int  | 
    
    
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    BpfOpen(void)  | 
    
    
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    { | 
    
    
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    	struct ifreq ifr;  | 
    
    
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    	int n;  | 
    
    
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    	if ((BpfFd = open("/dev/bpf", O_RDWR)) == -1) { | 
    
    
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    		syslog(LOG_ERR, "bpf: can't open device: %m");  | 
    
    
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    		DoExit();  | 
    
    
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    	}  | 
    
    
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    	/*  | 
    
    
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    	 *  Set interface name for bpf device, get data link layer  | 
    
    
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    	 *  type and make sure it's type Ethernet.  | 
    
    
    95  | 
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    	 */  | 
    
    
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    	(void) strncpy(ifr.ifr_name, IntfName, sizeof(ifr.ifr_name));  | 
    
    
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    	if (ioctl(BpfFd, BIOCSETIF, (caddr_t)&ifr) < 0) { | 
    
    
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    		syslog(LOG_ERR, "bpf: ioctl(BIOCSETIF,%s): %m", IntfName);  | 
    
    
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    		DoExit();  | 
    
    
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    	}  | 
    
    
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    	/*  | 
    
    
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    	 *  Make sure we are dealing with an Ethernet device.  | 
    
    
    104  | 
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    	 */  | 
    
    
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    	if (ioctl(BpfFd, BIOCGDLT, (caddr_t)&n) < 0) { | 
    
    
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    		syslog(LOG_ERR, "bpf: ioctl(BIOCGDLT): %m");  | 
    
    
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    		DoExit();  | 
    
    
    108  | 
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    	}  | 
    
    
    109  | 
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    	if (n != DLT_EN10MB) { | 
    
    
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    		syslog(LOG_ERR,"bpf: %s: data-link type %d unsupported",  | 
    
    
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    		    IntfName, n);  | 
    
    
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    		DoExit();  | 
    
    
    113  | 
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    	}  | 
    
    
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    	/*  | 
    
    
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    	 *  On read(), return packets immediately (do not buffer them).  | 
    
    
    117  | 
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    	 */  | 
    
    
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    	n = 1;  | 
    
    
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    	if (ioctl(BpfFd, BIOCIMMEDIATE, (caddr_t)&n) < 0) { | 
    
    
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    		syslog(LOG_ERR, "bpf: ioctl(BIOCIMMEDIATE): %m");  | 
    
    
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    		DoExit();  | 
    
    
    122  | 
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    	}  | 
    
    
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    	/*  | 
    
    
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    	 *  Try to enable the chip/driver's multicast address filter to  | 
    
    
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    	 *  grab our RMP address.  If this fails, try promiscuous mode.  | 
    
    
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    	 *  If this fails, there's no way we are going to get any RMP  | 
    
    
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    	 *  packets so just exit here.  | 
    
    
    129  | 
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    	 */  | 
    
    
    130  | 
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    #ifdef MSG_EOR  | 
    
    
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    	ifr.ifr_addr.sa_len = RMP_ADDRLEN + 2;  | 
    
    
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    #endif  | 
    
    
    133  | 
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    	ifr.ifr_addr.sa_family = AF_UNSPEC;  | 
    
    
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    	bcopy(&RmpMcastAddr[0], (char *)&ifr.ifr_addr.sa_data[0], RMP_ADDRLEN);  | 
    
    
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    	if (ioctl(BpfFd, SIOCADDMULTI, (caddr_t)&ifr) < 0) { | 
    
    
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    		syslog(LOG_WARNING,  | 
    
    
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    		    "bpf: can't add mcast addr (%m), setting promiscuous mode");  | 
    
    
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    		if (ioctl(BpfFd, BIOCPROMISC, (caddr_t)0) < 0) { | 
    
    
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    			syslog(LOG_ERR, "bpf: can't set promiscuous mode: %m");  | 
    
    
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    			DoExit();  | 
    
    
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    		}  | 
    
    
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    	}  | 
    
    
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    	/*  | 
    
    
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    	 *  Ask BPF how much buffer space it requires and allocate one.  | 
    
    
    147  | 
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    	 */  | 
    
    
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    	if (ioctl(BpfFd, BIOCGBLEN, (caddr_t)&BpfLen) < 0) { | 
    
    
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    		syslog(LOG_ERR, "bpf: ioctl(BIOCGBLEN): %m");  | 
    
    
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    		DoExit();  | 
    
    
    151  | 
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    	}  | 
    
    
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    	if (BpfPkt == NULL)  | 
    
    
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    		BpfPkt = malloc(BpfLen);  | 
    
    
    154  | 
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    	if (BpfPkt == NULL) { | 
    
    
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    		syslog(LOG_ERR, "bpf: out of memory (%u bytes for bpfpkt)",  | 
    
    
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    		    BpfLen);  | 
    
    
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    		DoExit();  | 
    
    
    159  | 
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    	}  | 
    
    
    160  | 
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    161  | 
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    	/*  | 
    
    
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    	 *  Write a little program to snarf RMP Boot packets and stuff  | 
    
    
    163  | 
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    	 *  it down BPF's throat (i.e. set up the packet filter).  | 
    
    
    164  | 
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    	 */  | 
    
    
    165  | 
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    	{ | 
    
    
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    #define	RMP(field)	offsetof(struct rmp_packet, field)  | 
    
    
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    		static struct bpf_insn bpf_insn[] = { | 
    
    
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    		    /* make sure it is a 802.3 packet */  | 
    
    
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    		    { BPF_LD|BPF_H|BPF_ABS,  0, 0, RMP(hp_hdr.len) }, | 
    
    
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    		    { BPF_JMP|BPF_JGE|BPF_K, 7, 0, 0x600 }, | 
    
    
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    		    { BPF_LD|BPF_B|BPF_ABS,  0, 0, RMP(hp_llc.dsap) }, | 
    
    
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    		    { BPF_JMP|BPF_JEQ|BPF_K, 0, 5, IEEE_DSAP_HP }, | 
    
    
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    		    { BPF_LD|BPF_H|BPF_ABS,  0, 0, RMP(hp_llc.cntrl) }, | 
    
    
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    		    { BPF_JMP|BPF_JEQ|BPF_K, 0, 3, IEEE_CNTL_HP }, | 
    
    
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    		    { BPF_LD|BPF_H|BPF_ABS,  0, 0, RMP(hp_llc.dxsap) }, | 
    
    
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    		    { BPF_JMP|BPF_JEQ|BPF_K, 0, 1, HPEXT_DXSAP }, | 
    
    
    178  | 
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    		    { BPF_RET|BPF_K,         0, 0, RMP_MAX_PACKET }, | 
    
    
    179  | 
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    		    { BPF_RET|BPF_K,         0, 0, 0x0 } | 
    
    
    180  | 
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    		};  | 
    
    
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    		static struct bpf_insn bpf_wf_insn[] = { | 
    
    
    183  | 
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    		    /* make sure it is a 802.3 packet */  | 
    
    
    184  | 
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    		    { BPF_LD|BPF_H|BPF_ABS,  0, 0, RMP(hp_hdr.len) }, | 
    
    
    185  | 
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    		    { BPF_JMP|BPF_JGE|BPF_K, 12, 0, 0x600 }, | 
    
    
    186  | 
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    187  | 
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    		    /* check the SNAP header */  | 
    
    
    188  | 
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    		    { BPF_LD|BPF_B|BPF_ABS,  0, 0, RMP(hp_llc.dsap) }, | 
    
    
    189  | 
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    		    { BPF_JMP|BPF_JEQ|BPF_K, 0, 10, IEEE_DSAP_HP }, | 
    
    
    190  | 
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    		    { BPF_LD|BPF_H|BPF_ABS,  0, 0, RMP(hp_llc.cntrl) }, | 
    
    
    191  | 
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    		    { BPF_JMP|BPF_JEQ|BPF_K, 0, 8, IEEE_CNTL_HP }, | 
    
    
    192  | 
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    193  | 
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    		    { BPF_LD|BPF_H|BPF_ABS,  0, 0, RMP(hp_llc.sxsap) }, | 
    
    
    194  | 
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    		    { BPF_JMP|BPF_JEQ|BPF_K, 0, 6, HPEXT_DXSAP }, | 
    
    
    195  | 
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    		    { BPF_LD|BPF_H|BPF_ABS,  0, 0, RMP(hp_llc.dxsap) }, | 
    
    
    196  | 
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    		    { BPF_JMP|BPF_JEQ|BPF_K, 0, 4, HPEXT_SXSAP }, | 
    
    
    197  | 
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    198  | 
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    		    /* check return type code */  | 
    
    
    199  | 
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    		    { BPF_LD|BPF_B|BPF_ABS,  0, 0, | 
    
    
    200  | 
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    		        RMP(rmp_proto.rmp_raw.rmp_type) },  | 
    
    
    201  | 
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    		    { BPF_JMP|BPF_JEQ|BPF_K, 1, 0, RMP_BOOT_REPL }, | 
    
    
    202  | 
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    		    { BPF_JMP|BPF_JEQ|BPF_K, 0, 1, RMP_READ_REPL }, | 
    
    
    203  | 
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    204  | 
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    		    { BPF_RET|BPF_K,         0, 0, RMP_MAX_PACKET }, | 
    
    
    205  | 
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    		    { BPF_RET|BPF_K,         0, 0, 0x0 } | 
    
    
    206  | 
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    		};  | 
    
    
    207  | 
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    #undef	RMP  | 
    
    
    208  | 
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    		static struct bpf_program bpf_pgm = { | 
    
    
    209  | 
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    			sizeof(bpf_insn)/sizeof(bpf_insn[0]), bpf_insn  | 
    
    
    210  | 
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    		};  | 
    
    
    211  | 
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    212  | 
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    		static struct bpf_program bpf_w_pgm = { | 
    
    
    213  | 
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    			sizeof(bpf_wf_insn)/sizeof(bpf_wf_insn[0]), bpf_wf_insn  | 
    
    
    214  | 
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    		};  | 
    
    
    215  | 
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    216  | 
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    		if (ioctl(BpfFd, BIOCSETF, (caddr_t)&bpf_pgm) < 0) { | 
    
    
    217  | 
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    			syslog(LOG_ERR, "bpf: ioctl(BIOCSETF): %m");  | 
    
    
    218  | 
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    			DoExit();  | 
    
    
    219  | 
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    		}  | 
    
    
    220  | 
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    221  | 
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    		if (ioctl(BpfFd, BIOCSETWF, (caddr_t)&bpf_w_pgm) < 0) { | 
    
    
    222  | 
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    			syslog(LOG_ERR, "bpf: ioctl(BIOCSETWF): %m");  | 
    
    
    223  | 
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    			DoExit();  | 
    
    
    224  | 
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    		}  | 
    
    
    225  | 
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    226  | 
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    		if (ioctl(BpfFd, BIOCLOCK) < 0) { | 
    
    
    227  | 
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    			syslog(LOG_ERR, "bpf: ioctl(BIOCLOCK): %m");  | 
    
    
    228  | 
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    			DoExit();  | 
    
    
    229  | 
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    		}  | 
    
    
    230  | 
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    	}  | 
    
    
    231  | 
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    232  | 
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    	return(BpfFd);  | 
    
    
    233  | 
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    }  | 
    
    
    234  | 
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    235  | 
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    /*  | 
    
    
    236  | 
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    **  BPF GetIntfName -- Return the name of a network interface attached to  | 
    
    
    237  | 
     | 
     | 
    **		the system, or 0 if none can be found.  The interface  | 
    
    
    238  | 
     | 
     | 
    **		must be configured up; the lowest unit number is  | 
    
    
    239  | 
     | 
     | 
    **		preferred; loopback is ignored.  | 
    
    
    240  | 
     | 
     | 
    **  | 
    
    
    241  | 
     | 
     | 
    **	Parameters:  | 
    
    
    242  | 
     | 
     | 
    **		errmsg - if no network interface found, *errmsg explains why.  | 
    
    
    243  | 
     | 
     | 
    **  | 
    
    
    244  | 
     | 
     | 
    **	Returns:  | 
    
    
    245  | 
     | 
     | 
    **		A (static) pointer to interface name, or NULL on error.  | 
    
    
    246  | 
     | 
     | 
    **  | 
    
    
    247  | 
     | 
     | 
    **	Side Effects:  | 
    
    
    248  | 
     | 
     | 
    **		None.  | 
    
    
    249  | 
     | 
     | 
    */  | 
    
    
    250  | 
     | 
     | 
    char *  | 
    
    
    251  | 
     | 
     | 
    BpfGetIntfName(char **errmsg)  | 
    
    
    252  | 
     | 
     | 
    { | 
    
    
    253  | 
     | 
     | 
    	int minunit = 999, n;  | 
    
    
    254  | 
     | 
     | 
    	char *cp;  | 
    
    
    255  | 
     | 
     | 
    	const char *errstr;  | 
    
    
    256  | 
     | 
     | 
    	static char device[IFNAMSIZ];  | 
    
    
    257  | 
     | 
     | 
    	static char errbuf[128] = "No Error!";  | 
    
    
    258  | 
     | 
     | 
    	struct ifaddrs *ifap, *ifa, *mp = NULL;  | 
    
    
    259  | 
     | 
     | 
     | 
    
    
    260  | 
     | 
     | 
    	if (errmsg != NULL)  | 
    
    
    261  | 
     | 
     | 
    		*errmsg = errbuf;  | 
    
    
    262  | 
     | 
     | 
     | 
    
    
    263  | 
     | 
     | 
    	if (getifaddrs(&ifap) != 0) { | 
    
    
    264  | 
     | 
     | 
    		(void) strlcpy(errbuf, "bpf: getifaddrs: %m", sizeof(errbuf));  | 
    
    
    265  | 
     | 
     | 
    		return(NULL);  | 
    
    
    266  | 
     | 
     | 
    	}  | 
    
    
    267  | 
     | 
     | 
     | 
    
    
    268  | 
     | 
     | 
    	for (ifa = ifap; ifa; ifa = ifa->ifa_next) { | 
    
    
    269  | 
     | 
     | 
    		/*  | 
    
    
    270  | 
     | 
     | 
    		 *  If interface is down or this is the loopback interface,  | 
    
    
    271  | 
     | 
     | 
    		 *  ignore it.  | 
    
    
    272  | 
     | 
     | 
    		 */  | 
    
    
    273  | 
     | 
     | 
    		if ((ifa->ifa_flags & IFF_UP) == 0 ||  | 
    
    
    274  | 
     | 
     | 
    #ifdef IFF_LOOPBACK  | 
    
    
    275  | 
     | 
     | 
    		    (ifa->ifa_flags & IFF_LOOPBACK))  | 
    
    
    276  | 
     | 
     | 
    #else  | 
    
    
    277  | 
     | 
     | 
    		    (strcmp(ifa->ifa_name, "lo0") == 0))  | 
    
    
    278  | 
     | 
     | 
    #endif  | 
    
    
    279  | 
     | 
     | 
    			continue;  | 
    
    
    280  | 
     | 
     | 
     | 
    
    
    281  | 
     | 
     | 
    		for (cp = ifa->ifa_name; !isdigit((unsigned char)*cp); ++cp)  | 
    
    
    282  | 
     | 
     | 
    			;  | 
    
    
    283  | 
     | 
     | 
    		n = strtonum(cp, 0, INT_MAX, &errstr);  | 
    
    
    284  | 
     | 
     | 
    		if (errstr == NULL && n < minunit) { | 
    
    
    285  | 
     | 
     | 
    			minunit = n;  | 
    
    
    286  | 
     | 
     | 
    			mp = ifa;  | 
    
    
    287  | 
     | 
     | 
    		}  | 
    
    
    288  | 
     | 
     | 
    	}  | 
    
    
    289  | 
     | 
     | 
     | 
    
    
    290  | 
     | 
     | 
    	if (mp == 0) { | 
    
    
    291  | 
     | 
     | 
    		(void) strlcpy(errbuf, "bpf: no interfaces found",  | 
    
    
    292  | 
     | 
     | 
    		    sizeof(errbuf));  | 
    
    
    293  | 
     | 
     | 
    		freeifaddrs(ifap);  | 
    
    
    294  | 
     | 
     | 
    		return(NULL);  | 
    
    
    295  | 
     | 
     | 
    	}  | 
    
    
    296  | 
     | 
     | 
     | 
    
    
    297  | 
     | 
     | 
    	(void) strlcpy(device, mp->ifa_name, sizeof device);  | 
    
    
    298  | 
     | 
     | 
    	freeifaddrs(ifap);  | 
    
    
    299  | 
     | 
     | 
    	return(device);  | 
    
    
    300  | 
     | 
     | 
    }  | 
    
    
    301  | 
     | 
     | 
     | 
    
    
    302  | 
     | 
     | 
    /*  | 
    
    
    303  | 
     | 
     | 
    **  BpfRead -- Read packets from a BPF device and fill in `rconn'.  | 
    
    
    304  | 
     | 
     | 
    **  | 
    
    
    305  | 
     | 
     | 
    **	Parameters:  | 
    
    
    306  | 
     | 
     | 
    **		rconn - filled in with next packet.  | 
    
    
    307  | 
     | 
     | 
    **		doread - is True if we can issue a read() syscall.  | 
    
    
    308  | 
     | 
     | 
    **  | 
    
    
    309  | 
     | 
     | 
    **	Returns:  | 
    
    
    310  | 
     | 
     | 
    **		True if `rconn' contains a new packet, False otherwise.  | 
    
    
    311  | 
     | 
     | 
    **  | 
    
    
    312  | 
     | 
     | 
    **	Side Effects:  | 
    
    
    313  | 
     | 
     | 
    **		None.  | 
    
    
    314  | 
     | 
     | 
    */  | 
    
    
    315  | 
     | 
     | 
    int  | 
    
    
    316  | 
     | 
     | 
    BpfRead(RMPCONN *rconn, int doread)  | 
    
    
    317  | 
     | 
     | 
    { | 
    
    
    318  | 
     | 
     | 
    	int datlen, caplen, hdrlen;  | 
    
    
    319  | 
     | 
     | 
    	static u_int8_t *bp = NULL, *ep = NULL;  | 
    
    
    320  | 
     | 
     | 
    	int cc;  | 
    
    
    321  | 
     | 
     | 
     | 
    
    
    322  | 
     | 
     | 
    	/*  | 
    
    
    323  | 
     | 
     | 
    	 *  The read() may block, or it may return one or more packets.  | 
    
    
    324  | 
     | 
     | 
    	 *  We let the caller decide whether or not we can issue a read().  | 
    
    
    325  | 
     | 
     | 
    	 */  | 
    
    
    326  | 
     | 
     | 
    	if (doread) { | 
    
    
    327  | 
     | 
     | 
    		if ((cc = read(BpfFd, (char *)BpfPkt, (int)BpfLen)) < 0) { | 
    
    
    328  | 
     | 
     | 
    			syslog(LOG_ERR, "bpf: read: %m");  | 
    
    
    329  | 
     | 
     | 
    			return(0);  | 
    
    
    330  | 
     | 
     | 
    		} else { | 
    
    
    331  | 
     | 
     | 
    			bp = BpfPkt;  | 
    
    
    332  | 
     | 
     | 
    			ep = BpfPkt + cc;  | 
    
    
    333  | 
     | 
     | 
    		}  | 
    
    
    334  | 
     | 
     | 
    	}  | 
    
    
    335  | 
     | 
     | 
     | 
    
    
    336  | 
     | 
     | 
    #define bhp ((struct bpf_hdr *)bp)  | 
    
    
    337  | 
     | 
     | 
    	/*  | 
    
    
    338  | 
     | 
     | 
    	 *  If there is a new packet in the buffer, stuff it into `rconn'  | 
    
    
    339  | 
     | 
     | 
    	 *  and return a success indication.  | 
    
    
    340  | 
     | 
     | 
    	 */  | 
    
    
    341  | 
     | 
     | 
    	if (bp < ep) { | 
    
    
    342  | 
     | 
     | 
    		datlen = bhp->bh_datalen;  | 
    
    
    343  | 
     | 
     | 
    		caplen = bhp->bh_caplen;  | 
    
    
    344  | 
     | 
     | 
    		hdrlen = bhp->bh_hdrlen;  | 
    
    
    345  | 
     | 
     | 
     | 
    
    
    346  | 
     | 
     | 
    		if (caplen != datlen)  | 
    
    
    347  | 
     | 
     | 
    			syslog(LOG_ERR,  | 
    
    
    348  | 
     | 
     | 
    			    "bpf: short packet dropped (%d of %d bytes)",  | 
    
    
    349  | 
     | 
     | 
    			    caplen, datlen);  | 
    
    
    350  | 
     | 
     | 
    		else if (caplen > sizeof(struct rmp_packet))  | 
    
    
    351  | 
     | 
     | 
    			syslog(LOG_ERR, "bpf: large packet dropped (%d bytes)",  | 
    
    
    352  | 
     | 
     | 
    			    caplen);  | 
    
    
    353  | 
     | 
     | 
    		else { | 
    
    
    354  | 
     | 
     | 
    			rconn->rmplen = caplen;  | 
    
    
    355  | 
     | 
     | 
    			rconn->tstamp.tv_sec = bhp->bh_tstamp.tv_sec;  | 
    
    
    356  | 
     | 
     | 
    			rconn->tstamp.tv_usec = bhp->bh_tstamp.tv_usec;  | 
    
    
    357  | 
     | 
     | 
    			bcopy((char *)bp + hdrlen, (char *)&rconn->rmp, caplen);  | 
    
    
    358  | 
     | 
     | 
    		}  | 
    
    
    359  | 
     | 
     | 
    		bp += BPF_WORDALIGN(caplen + hdrlen);  | 
    
    
    360  | 
     | 
     | 
    		return(1);  | 
    
    
    361  | 
     | 
     | 
    	}  | 
    
    
    362  | 
     | 
     | 
    #undef bhp  | 
    
    
    363  | 
     | 
     | 
     | 
    
    
    364  | 
     | 
     | 
    	return(0);  | 
    
    
    365  | 
     | 
     | 
    }  | 
    
    
    366  | 
     | 
     | 
     | 
    
    
    367  | 
     | 
     | 
    /*  | 
    
    
    368  | 
     | 
     | 
    **  BpfWrite -- Write packet to BPF device.  | 
    
    
    369  | 
     | 
     | 
    **  | 
    
    
    370  | 
     | 
     | 
    **	Parameters:  | 
    
    
    371  | 
     | 
     | 
    **		rconn - packet to send.  | 
    
    
    372  | 
     | 
     | 
    **  | 
    
    
    373  | 
     | 
     | 
    **	Returns:  | 
    
    
    374  | 
     | 
     | 
    **		True if write succeeded, False otherwise.  | 
    
    
    375  | 
     | 
     | 
    **  | 
    
    
    376  | 
     | 
     | 
    **	Side Effects:  | 
    
    
    377  | 
     | 
     | 
    **		None.  | 
    
    
    378  | 
     | 
     | 
    */  | 
    
    
    379  | 
     | 
     | 
    int  | 
    
    
    380  | 
     | 
     | 
    BpfWrite(RMPCONN *rconn)  | 
    
    
    381  | 
     | 
     | 
    { | 
    
    
    382  | 
     | 
     | 
    	if (write(BpfFd, (char *)&rconn->rmp, rconn->rmplen) < 0) { | 
    
    
    383  | 
     | 
     | 
    		syslog(LOG_ERR, "write: %s: %m", EnetStr(rconn));  | 
    
    
    384  | 
     | 
     | 
    		return(0);  | 
    
    
    385  | 
     | 
     | 
    	}  | 
    
    
    386  | 
     | 
     | 
     | 
    
    
    387  | 
     | 
     | 
    	return(1);  | 
    
    
    388  | 
     | 
     | 
    }  |