pcap-dlpi.c

用来监视网络通信数据的源代码和应用程序,方便网络程序底层开发.

/*
 * Copyright (c) 1993, 1994, 1995, 1996, 1997
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that: (1) source code distributions
 * retain the above copyright notice and this paragraph in its entirety, (2)
 * distributions including binary code include the above copyright notice and
 * this paragraph in its entirety in the documentation or other materials
 * provided with the distribution, and (3) all advertising materials mentioning
 * features or use of this software display the following acknowledgement:
 * ``This product includes software developed by the University of California,
 * Lawrence Berkeley Laboratory and its contributors.'' 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * This code contributed by Atanu Ghosh ([e-mail]),
 * University College London.
 */

/*
 * Packet capture routine for DLPI under SunOS 5, HP-UX 9/10/11, and AIX.
 *
 * Notes:
 *
 *    - Apparently the DLIOCRAW ioctl() is specific to SunOS.
 *
 *    - There is a bug in bufmod(7) such that setting the snapshot
 *      length results in data being left of the front of the packet.
 *
 *    - It might be desirable to use pfmod(7) to filter packets in the
 *      kernel when possible.
 */

#ifndef lint
static const char rcsid[] =
    "@(#) $Header: /tcpdump/master/libpcap/pcap-dlpi.c,v 1.82 2003/01/03 08:33:54 guy Exp $ (LBL)";
#endif

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <sys/types.h>
#include <sys/time.h>
#ifdef HAVE_SYS_BUFMOD_H
#include <sys/bufmod.h>
#endif
#include <sys/dlpi.h>
#ifdef HAVE_SYS_DLPI_EXT_H
#include <sys/dlpi_ext.h>
#endif
#ifdef HAVE_HPUX9
#include <sys/socket.h>
#endif
#ifdef DL_HP_PPA_ACK_OBS
#include <sys/stat.h>
#endif
#include <sys/stream.h>
#if defined(HAVE_SOLARIS) && defined(HAVE_SYS_BUFMOD_H)
#include <sys/systeminfo.h>
#endif

#ifdef HAVE_HPUX9
#include <net/if.h>
#endif

#include <ctype.h>
#ifdef HAVE_HPUX9
#include <nlist.h>
#endif
#include <errno.h>
#include <fcntl.h>
#include <memory.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stropts.h>
#include <unistd.h>

#include "pcap-int.h"

#ifdef HAVE_OS_PROTO_H
#include "os-proto.h"
#endif

#ifndef PCAP_DEV_PREFIX
#ifdef _AIX
#define PCAP_DEV_PREFIX "/dev/dlpi"
#else
#define PCAP_DEV_PREFIX "/dev"
#endif
#endif

#define	MAXDLBUF	8192

/* Forwards */
static char *split_dname(char *, int *, char *);
static int dlattachreq(int, bpf_u_int32, char *);
static int dlbindack(int, char *, char *);
static int dlbindreq(int, bpf_u_int32, char *);
static int dlinfoack(int, char *, char *);
static int dlinforeq(int, char *);
static int dlokack(int, const char *, char *, char *);
static int recv_ack(int, int, const char *, char *, char *);
static char *dlstrerror(bpf_u_int32);
static char *dlprim(bpf_u_int32);
static int dlpromisconreq(int, bpf_u_int32, char *);
#if defined(HAVE_SOLARIS) && defined(HAVE_SYS_BUFMOD_H)
static char *get_release(bpf_u_int32 *, bpf_u_int32 *, bpf_u_int32 *);
#endif
static int send_request(int, char *, int, char *, char *);
#ifdef HAVE_SYS_BUFMOD_H
static int strioctl(int, int, int, char *);
#endif
#ifdef HAVE_HPUX9
static int dlpi_kread(int, off_t, void *, u_int, char *);
#endif
#ifdef HAVE_DEV_DLPI
static int get_dlpi_ppa(int, const char *, int, char *);
#endif

int
pcap_stats(pcap_t *p, struct pcap_stat *ps)
{

	/*
	 * "ps_recv" counts packets handed to the filter, not packets
	 * that passed the filter.  As filtering is done in userland,
	 * this does not include packets dropped because we ran out
	 * of buffer space.
	 *
	 * "ps_drop" counts packets dropped inside the DLPI service
	 * provider device device because of flow control requirements
	 * or resource exhaustion; it doesn't count packets dropped by
	 * the interface driver, or packets dropped upstream.  As
	 * filtering is done in userland, it counts packets regardless
	 * of whether they would've passed the filter.
	 *
	 * These statistics don't include packets not yet read from
	 * the kernel by libpcap, but they may include packets not
	 * yet read from libpcap by the application.
	 */
	*ps = p->md.stat;
	return (0);
}

/* XXX Needed by HP-UX (at least) */
static bpf_u_int32 ctlbuf[MAXDLBUF];
static struct strbuf ctl = {
	MAXDLBUF,
	0,
	(char *)ctlbuf
};

int
pcap_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
{
	register int cc, n, caplen, origlen;
	register u_char *bp, *ep, *pk;
	register struct bpf_insn *fcode;
#ifdef HAVE_SYS_BUFMOD_H
	register struct sb_hdr *sbp;
#ifdef LBL_ALIGN
	struct sb_hdr sbhdr;
#endif
#endif
	int flags;
	struct strbuf data;
	struct pcap_pkthdr pkthdr;

	flags = 0;
	cc = p->cc;
	if (cc == 0) {
		data.buf = (char *)p->buffer + p->offset;
		data.maxlen = p->bufsize;
		data.len = 0;
		do {
			if (getmsg(p->fd, &ctl, &data, &flags) < 0) {
				/* Don't choke when we get ptraced */
				if (errno == EINTR) {
					cc = 0;
					continue;
				}
				strlcpy(p->errbuf, pcap_strerror(errno),
				    sizeof(p->errbuf));
				return (-1);
			}
			cc = data.len;
		} while (cc == 0);
		bp = p->buffer + p->offset;
	} else
		bp = p->bp;

	/* Loop through packets */
	fcode = p->fcode.bf_insns;
	ep = bp + cc;
	n = 0;
#ifdef HAVE_SYS_BUFMOD_H
	while (bp < ep) {
#ifdef LBL_ALIGN
		if ((long)bp & 3) {
			sbp = &sbhdr;
			memcpy(sbp, bp, sizeof(*sbp));
		} else
#endif
			sbp = (struct sb_hdr *)bp;
		p->md.stat.ps_drop += sbp->sbh_drops;
		pk = bp + sizeof(*sbp);
		bp += sbp->sbh_totlen;
		origlen = sbp->sbh_origlen;
		caplen = sbp->sbh_msglen;
#else
		origlen = cc;
		caplen = min(p->snapshot, cc);
		pk = bp;
		bp += caplen;
#endif
		++p->md.stat.ps_recv;
		if (bpf_filter(fcode, pk, origlen, caplen)) {
#ifdef HAVE_SYS_BUFMOD_H
			pkthdr.ts.tv_sec = sbp->sbh_timestamp.tv_sec;
			pkthdr.ts.tv_usec = sbp->sbh_timestamp.tv_usec;
#else
			(void)gettimeofday(&pkthdr.ts, NULL);
#endif
			pkthdr.len = origlen;
			pkthdr.caplen = caplen;
			/* Insure caplen does not exceed snapshot */
			if (pkthdr.caplen > p->snapshot)
				pkthdr.caplen = p->snapshot;
			(*callback)(user, &pkthdr, pk);
			if (++n >= cnt && cnt >= 0) {
				p->cc = ep - bp;
				p->bp = bp;
				return (n);
			}
		}
#ifdef HAVE_SYS_BUFMOD_H
	}
#endif
	p->cc = 0;
	return (n);
}

#ifndef DL_IPATM
#define DL_IPATM	0x12	/* ATM Classical IP interface */
#endif

#ifdef HAVE_SOLARIS
/*
 * For SunATM.
 */
#ifndef A_GET_UNITS
#define A_GET_UNITS	(('A'<<8)|118)
#endif /* A_GET_UNITS */
#ifndef A_PROMISCON_REQ
#define A_PROMISCON_REQ	(('A'<<8)|121)
#endif /* A_PROMISCON_REQ */
#endif /* HAVE_SOLARIS */

pcap_t *
pcap_open_live(const char *device, int snaplen, int promisc, int to_ms,
    char *ebuf)
{
	register char *cp;
	register pcap_t *p;
	int ppa;
#ifdef HAVE_SOLARIS
	int isatm = 0;
#endif
	register dl_info_ack_t *infop;
#ifdef HAVE_SYS_BUFMOD_H
	bpf_u_int32 ss, flag;
#ifdef HAVE_SOLARIS
	register char *release;
	bpf_u_int32 osmajor, osminor, osmicro;
#endif
#endif
	bpf_u_int32 buf[MAXDLBUF];
	char dname[100];
#ifndef HAVE_DEV_DLPI
	char dname2[100];
#endif

	p = (pcap_t *)malloc(sizeof(*p));
	if (p == NULL) {
		strlcpy(ebuf, pcap_strerror(errno), PCAP_ERRBUF_SIZE);
		return (NULL);
	}
	memset(p, 0, sizeof(*p));
	p->fd = -1;	/* indicate that it hasn't been opened yet */

#ifdef HAVE_DEV_DLPI
	/*
	** Remove any "/dev/" on the front of the device.
	*/
	cp = strrchr(device, '/');
	if (cp == NULL)
		strlcpy(dname, device, sizeof(dname));
	else
		strlcpy(dname, cp + 1, sizeof(dname));

	/*
	 * Split the device name into a device type name and a unit number;
	 * chop off the unit number, so "dname" is just a device type name.
	 */
	cp = split_dname(dname, &ppa, ebuf);
	if (cp == NULL)
		goto bad;
	*cp = '\0';

	/*
	 * Use "/dev/dlpi" as the device.
	 *
	 * XXX - HP's DLPI Programmer's Guide for HP-UX 11.00 says that
	 * the "dl_mjr_num" field is for the "major number of interface
	 * driver"; that's the major of "/dev/dlpi" on the system on
	 * which I tried this, but there may be DLPI devices that
	 * use a different driver, in which case we may need to
	 * search "/dev" for the appropriate device with that major
	 * device number, rather than hardwiring "/dev/dlpi".
	 */
	cp = "/dev/dlpi";
	if ((p->fd = open(cp, O_RDWR)) < 0) {
		snprintf(ebuf, PCAP_ERRBUF_SIZE,
		    "%s: %s", cp, pcap_strerror(errno));
		goto bad;
	}

	/*
	 * Get a table of all PPAs for that device, and search that
	 * table for the specified device type name and unit number.
	 */
	ppa = get_dlpi_ppa(p->fd, dname, ppa, ebuf);
	if (ppa < 0)
		goto bad;
#else
	/*
	 * If the device name begins with "/", assume it begins with
	 * the pathname of the directory containing the device to open;
	 * otherwise, concatenate the device directory name and the
	 * device name.
	 */
	if (*device == '/')
		strlcpy(dname, device, sizeof(dname));
	else
		snprintf(dname, sizeof(dname), "%s/%s", PCAP_DEV_PREFIX,
		    device);

	/*
	 * Get the unit number, and a pointer to the end of the device
	 * type name.
	 */
	cp = split_dname(dname, &ppa, ebuf);
	if (cp == NULL)
		goto bad;

	/*
	 * Make a copy of the device pathname, and then remove the unit
	 * number from the device pathname.
	 */
	strlcpy(dname2, dname, sizeof(dname));
	*cp = '\0';

	/* Try device without unit number */
	if ((p->fd = open(dname, O_RDWR)) < 0) {
		if (errno != ENOENT) {
			snprintf(ebuf, PCAP_ERRBUF_SIZE, "%s: %s", dname,
			    pcap_strerror(errno));
			goto bad;
		}

		/* Try again with unit number */
		if ((p->fd = open(dname2, O_RDWR)) < 0) {
			snprintf(ebuf, PCAP_ERRBUF_SIZE, "%s: %s", dname2,
			    pcap_strerror(errno));
			goto bad;
		}
		/* XXX Assume unit zero */
		ppa = 0;
	}
#endif

	p->snapshot = snaplen;

	/*
	** Attach if "style 2" provider
	*/
	if (dlinforeq(p->fd, ebuf) < 0 ||
	    dlinfoack(p->fd, (char *)buf, ebuf) < 0)
		goto bad;
	infop = &((union DL_primitives *)buf)->info_ack;
#ifdef HAVE_SOLARIS
	if (infop->dl_mac_type == DL_IPATM)
		isatm = 1;
#endif
	if (infop->dl_provider_style == DL_STYLE2 &&
	    (dlattachreq(p->fd, ppa, ebuf) < 0 ||
	    dlokack(p->fd, "attach", (char *)buf, ebuf) < 0))
		goto bad;
	/*
	** Bind (defer if using HP-UX 9 or HP-UX 10.20, totally skip if
	** using SINIX)
	*/
#if !defined(HAVE_HPUX9) && !defined(HAVE_HPUX10_20) && !defined(sinix)
#ifdef _AIX
	/* According to IBM's AIX Support Line, the dl_sap value
	** should not be less than 0x600 (1536) for standard Ethernet.
	** However, we seem to get DL_BADADDR - "DLSAP addr in improper
	** format or invalid" - errors if we use 1537 on the "tr0"
	** device, which, given that its name starts with "tr" and that
	** it's IBM, probably means a Token Ring device.  (Perhaps we
	** need to use 1537 on "/dev/dlpi/en" because that device is for
	** D/I/X Ethernet, the "SAP" is actually an Ethernet type, and
	** it rejects invalid Ethernet types.)
	**
	** So if 1537 fails, we try 2, as Hyung Sik Yoon of IBM Korea
	** says that works on Token Ring (he says that 0 does *not*
	** work; perhaps that's considered an invalid LLC SAP value - I
	** assume the SAP value in a DLPI bind is an LLC SAP for network
	** types that use 802.2 LLC).
	*/
	if ((dlbindreq(p->fd, 1537, ebuf) < 0 &&
	     dlbindreq(p->fd, 2, ebuf) < 0) ||
#else
	if (dlbindreq(p->fd, 0, ebuf) < 0 ||
#endif
	    dlbindack(p->fd, (char *)buf, ebuf) < 0)
		goto bad;
#endif

#ifdef HAVE_SOLARIS
	if (isatm) {
		/*
		** Have to turn on some special ATM promiscuous mode
		** for SunATM.
		** Do *NOT* turn regular promiscuous mode on; it doesn't
		** help, and may break things.
		*/
		if (strioctl(p->fd, A_PROMISCON_REQ, 0, NULL) < 0) {
			snprintf(ebuf, PCAP_ERRBUF_SIZE, "A_PROMISCON_REQ: %s",
			    pcap_strerror(errno));
			goto bad;
		}
	} else
#endif
	if (promisc) {
		/*
		** Enable promiscuous
		*/
		if (dlpromisconreq(p->fd, DL_PROMISC_PHYS, ebuf) < 0 ||
		    dlokack(p->fd, "promisc_phys", (char *)buf, ebuf) < 0)
			goto bad;

		/*
		** Try to enable multicast (you would have thought
		** promiscuous would be sufficient). (Skip if using
		** HP-UX or SINIX)
		*/
#if !defined(__hpux) && !defined(sinix)
		if (dlpromisconreq(p->fd, DL_PROMISC_MULTI, ebuf) < 0 ||
		    dlokack(p->fd, "promisc_multi", (char *)buf, ebuf) < 0)
			fprintf(stderr,
			    "WARNING: DL_PROMISC_MULTI failed (%s)\n", ebuf);
#endif
	}
	/*
	** Try to enable sap (when not in promiscuous mode when using
	** using HP-UX, when not doing SunATM on Solaris, and never
	** under SINIX)
	*/
#ifndef sinix
	if (
#ifdef __hpux
	    !promisc &&
#endif
#ifdef HAVE_SOLARIS
	    !isatm &&
#endif
	    (dlpromisconreq(p->fd, DL_PROMISC_SAP, ebuf) < 0 ||