Local changes: - In contrib/libpcap/pcap/bpf.h, do not include pcap/dlt.h. Our system net/dlt.h is pulled in from net/bpf.h. - sys/net/dlt.h: Incorporate changes from libpcap 1.10.3. - lib/libpcap/Makefile: Update for libpcap 1.10.3. Changelog: https://git.tcpdump.org/libpcap/blob/95691ebe7564afa3faa5c6ba0dbd17e351be455a:/CHANGES Reviewed by: emaste Obtained from: https://www.tcpdump.org/release/libpcap-1.10.3.tar.gz Sponsored by: The FreeBSD Foundation
700 lines
17 KiB
C
700 lines
17 KiB
C
/*
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* Copyright (c) 1993, 1994, 1995, 1996, 1997
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* The Regents of the University of California. All rights reserved.
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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: (1) source code distributions
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* retain the above copyright notice and this paragraph in its entirety, (2)
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* distributions including binary code include the above copyright notice and
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* this paragraph in its entirety in the documentation or other materials
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* provided with the distribution, and (3) all advertising materials mentioning
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* features or use of this software display the following acknowledgement:
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* ``This product includes software developed by the University of California,
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* Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
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* the University nor the names of its contributors may be used to endorse
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* or promote products derived from this software without specific prior
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* written permission.
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* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
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* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
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* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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*
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* savefile.c - supports offline use of tcpdump
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* Extraction/creation by Jeffrey Mogul, DECWRL
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* Modified by Steve McCanne, LBL.
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*
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* Used to save the received packet headers, after filtering, to
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* a file, and then read them later.
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* The first record in the file contains saved values for the machine
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* dependent values so we can print the dump file on any architecture.
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*/
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#ifdef HAVE_CONFIG_H
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#include <config.h>
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#endif
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#include <pcap-types.h>
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#ifdef _WIN32
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#include <io.h>
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#include <fcntl.h>
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#endif /* _WIN32 */
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#include <errno.h>
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#include <memory.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 <limits.h> /* for INT_MAX */
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#include "pcap-int.h"
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#ifdef HAVE_OS_PROTO_H
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#include "os-proto.h"
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#endif
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#include "sf-pcap.h"
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#include "sf-pcapng.h"
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#include "pcap-common.h"
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#include "charconv.h"
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#ifdef _WIN32
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/*
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* This isn't exported on Windows, because it would only work if both
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* WinPcap/Npcap and the code using it were to use the Universal CRT; otherwise,
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* a FILE structure in WinPcap/Npcap and a FILE structure in the code using it
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* could be different if they're using different versions of the C runtime.
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*
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* Instead, pcap/pcap.h defines it as a macro that wraps the hopen version,
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* with the wrapper calling _fileno() and _get_osfhandle() themselves,
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* so that it convert the appropriate CRT version's FILE structure to
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* a HANDLE (which is OS-defined, not CRT-defined, and is part of the Win32
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* and Win64 ABIs).
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*/
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static pcap_t *pcap_fopen_offline_with_tstamp_precision(FILE *, u_int, char *);
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#endif
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/*
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* Setting O_BINARY on DOS/Windows is a bit tricky
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*/
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#if defined(_WIN32)
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#define SET_BINMODE(f) _setmode(_fileno(f), _O_BINARY)
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#elif defined(MSDOS)
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#if defined(__HIGHC__)
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#define SET_BINMODE(f) setmode(f, O_BINARY)
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#else
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#define SET_BINMODE(f) setmode(fileno(f), O_BINARY)
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#endif
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#endif
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static int
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sf_getnonblock(pcap_t *p _U_)
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{
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/*
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* This is a savefile, not a live capture file, so never say
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* it's in non-blocking mode.
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*/
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return (0);
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}
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static int
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sf_setnonblock(pcap_t *p, int nonblock _U_)
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{
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/*
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* This is a savefile, not a live capture file, so reject
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* requests to put it in non-blocking mode. (If it's a
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* pipe, it could be put in non-blocking mode, but that
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* would significantly complicate the code to read packets,
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* as it would have to handle reading partial packets and
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* keeping the state of the read.)
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*/
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snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
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"Savefiles cannot be put into non-blocking mode");
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return (-1);
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}
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static int
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sf_cant_set_rfmon(pcap_t *p _U_)
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{
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/*
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* This is a savefile, not a device on which you can capture,
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* so never say it supports being put into monitor mode.
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*/
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return (0);
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}
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static int
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sf_stats(pcap_t *p, struct pcap_stat *ps _U_)
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{
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snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
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"Statistics aren't available from savefiles");
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return (-1);
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}
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#ifdef _WIN32
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static struct pcap_stat *
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sf_stats_ex(pcap_t *p, int *size _U_)
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{
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snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
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"Statistics aren't available from savefiles");
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return (NULL);
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}
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static int
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sf_setbuff(pcap_t *p, int dim _U_)
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{
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snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
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"The kernel buffer size cannot be set while reading from a file");
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return (-1);
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}
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static int
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sf_setmode(pcap_t *p, int mode _U_)
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{
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snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
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"impossible to set mode while reading from a file");
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return (-1);
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}
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static int
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sf_setmintocopy(pcap_t *p, int size _U_)
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{
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snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
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"The mintocopy parameter cannot be set while reading from a file");
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return (-1);
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}
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static HANDLE
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sf_getevent(pcap_t *pcap)
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{
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(void)snprintf(pcap->errbuf, sizeof(pcap->errbuf),
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"The read event cannot be retrieved while reading from a file");
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return (INVALID_HANDLE_VALUE);
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}
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static int
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sf_oid_get_request(pcap_t *p, bpf_u_int32 oid _U_, void *data _U_,
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size_t *lenp _U_)
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{
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snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
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"An OID get request cannot be performed on a file");
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return (PCAP_ERROR);
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}
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static int
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sf_oid_set_request(pcap_t *p, bpf_u_int32 oid _U_, const void *data _U_,
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size_t *lenp _U_)
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{
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snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
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"An OID set request cannot be performed on a file");
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return (PCAP_ERROR);
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}
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static u_int
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sf_sendqueue_transmit(pcap_t *p, pcap_send_queue *queue _U_, int sync _U_)
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{
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pcap_strlcpy(p->errbuf, "Sending packets isn't supported on savefiles",
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PCAP_ERRBUF_SIZE);
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return (0);
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}
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static int
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sf_setuserbuffer(pcap_t *p, int size _U_)
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{
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snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
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"The user buffer cannot be set when reading from a file");
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return (-1);
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}
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static int
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sf_live_dump(pcap_t *p, char *filename _U_, int maxsize _U_, int maxpacks _U_)
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{
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snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
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"Live packet dumping cannot be performed when reading from a file");
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return (-1);
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}
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static int
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sf_live_dump_ended(pcap_t *p, int sync _U_)
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{
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snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
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"Live packet dumping cannot be performed on a pcap_open_dead pcap_t");
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return (-1);
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}
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static PAirpcapHandle
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sf_get_airpcap_handle(pcap_t *pcap _U_)
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{
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return (NULL);
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}
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#endif
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static int
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sf_inject(pcap_t *p, const void *buf _U_, int size _U_)
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{
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pcap_strlcpy(p->errbuf, "Sending packets isn't supported on savefiles",
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PCAP_ERRBUF_SIZE);
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return (-1);
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}
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/*
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* Set direction flag: Which packets do we accept on a forwarding
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* single device? IN, OUT or both?
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*/
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static int
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sf_setdirection(pcap_t *p, pcap_direction_t d _U_)
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{
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snprintf(p->errbuf, sizeof(p->errbuf),
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"Setting direction is not supported on savefiles");
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return (-1);
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}
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void
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sf_cleanup(pcap_t *p)
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{
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if (p->rfile != stdin)
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(void)fclose(p->rfile);
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if (p->buffer != NULL)
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free(p->buffer);
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pcap_freecode(&p->fcode);
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}
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#ifdef _WIN32
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/*
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* Wrapper for fopen() and _wfopen().
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*
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* If we're in UTF-8 mode, map the pathname from UTF-8 to UTF-16LE and
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* call _wfopen().
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*
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* If we're not, just use fopen(); that'll treat it as being in the
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* local code page.
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*/
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FILE *
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charset_fopen(const char *path, const char *mode)
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{
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wchar_t *utf16_path;
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#define MAX_MODE_LEN 16
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wchar_t utf16_mode[MAX_MODE_LEN+1];
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int i;
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char c;
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FILE *fp;
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int save_errno;
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if (pcap_utf_8_mode) {
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/*
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* Map from UTF-8 to UTF-16LE.
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* Fail if there are invalid characters in the input
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* string, rather than converting them to REPLACEMENT
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* CHARACTER; the latter is appropriate for strings
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* to be displayed to the user, but for file names
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* you just want the attempt to open the file to fail.
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*/
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utf16_path = cp_to_utf_16le(CP_UTF8, path,
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MB_ERR_INVALID_CHARS);
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if (utf16_path == NULL) {
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/*
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* Error. Assume errno has been set.
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*
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* XXX - what about Windows errors?
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*/
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return (NULL);
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}
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/*
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* Now convert the mode to UTF-16LE as well.
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* We assume the mode is ASCII, and that
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* it's short, so that's easy.
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*/
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for (i = 0; (c = *mode) != '\0'; i++, mode++) {
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if (c > 0x7F) {
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/* Not an ASCII character; fail with EINVAL. */
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free(utf16_path);
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errno = EINVAL;
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return (NULL);
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}
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if (i >= MAX_MODE_LEN) {
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/* The mode string is longer than we allow. */
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free(utf16_path);
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errno = EINVAL;
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return (NULL);
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}
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utf16_mode[i] = c;
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}
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utf16_mode[i] = '\0';
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/*
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* OK, we have UTF-16LE strings; hand them to
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* _wfopen().
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*/
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fp = _wfopen(utf16_path, utf16_mode);
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/*
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* Make sure freeing the UTF-16LE string doesn't
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* overwrite the error code we got from _wfopen().
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*/
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save_errno = errno;
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free(utf16_path);
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errno = save_errno;
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return (fp);
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} else {
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/*
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* This takes strings in the local code page as an
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* argument.
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*/
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return (fopen(path, mode));
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}
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}
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#endif
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pcap_t *
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pcap_open_offline_with_tstamp_precision(const char *fname, u_int precision,
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char *errbuf)
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{
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FILE *fp;
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pcap_t *p;
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if (fname == NULL) {
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snprintf(errbuf, PCAP_ERRBUF_SIZE,
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"A null pointer was supplied as the file name");
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return (NULL);
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}
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if (fname[0] == '-' && fname[1] == '\0')
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{
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fp = stdin;
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if (fp == NULL) {
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snprintf(errbuf, PCAP_ERRBUF_SIZE,
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"The standard input is not open");
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return (NULL);
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}
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#if defined(_WIN32) || defined(MSDOS)
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/*
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* We're reading from the standard input, so put it in binary
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* mode, as savefiles are binary files.
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*/
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SET_BINMODE(fp);
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#endif
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}
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else {
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/*
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* Use charset_fopen(); on Windows, it tests whether we're
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* in "local code page" or "UTF-8" mode, and treats the
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* pathname appropriately, and on other platforms, it just
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* wraps fopen().
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*
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* "b" is supported as of C90, so *all* UN*Xes should
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* support it, even though it does nothing. For MS-DOS,
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* we again need it.
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*/
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fp = charset_fopen(fname, "rb");
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if (fp == NULL) {
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pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
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errno, "%s", fname);
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return (NULL);
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}
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}
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p = pcap_fopen_offline_with_tstamp_precision(fp, precision, errbuf);
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if (p == NULL) {
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if (fp != stdin)
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fclose(fp);
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}
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return (p);
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}
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pcap_t *
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pcap_open_offline(const char *fname, char *errbuf)
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{
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return (pcap_open_offline_with_tstamp_precision(fname,
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PCAP_TSTAMP_PRECISION_MICRO, errbuf));
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}
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#ifdef _WIN32
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pcap_t* pcap_hopen_offline_with_tstamp_precision(intptr_t osfd, u_int precision,
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char *errbuf)
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{
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int fd;
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FILE *file;
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fd = _open_osfhandle(osfd, _O_RDONLY);
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if ( fd < 0 )
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{
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pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
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errno, "_open_osfhandle");
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return NULL;
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}
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file = _fdopen(fd, "rb");
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if ( file == NULL )
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{
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pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
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errno, "_fdopen");
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_close(fd);
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return NULL;
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}
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return pcap_fopen_offline_with_tstamp_precision(file, precision,
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errbuf);
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}
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pcap_t* pcap_hopen_offline(intptr_t osfd, char *errbuf)
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{
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return pcap_hopen_offline_with_tstamp_precision(osfd,
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PCAP_TSTAMP_PRECISION_MICRO, errbuf);
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}
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#endif
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/*
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* Given a link-layer header type and snapshot length, return a
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* snapshot length to use when reading the file; it's guaranteed
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* to be > 0 and <= INT_MAX.
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*
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* XXX - the only reason why we limit it to <= INT_MAX is so that
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* it fits in p->snapshot, and the only reason that p->snapshot is
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* signed is that pcap_snapshot() returns an int, not an unsigned int.
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*/
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bpf_u_int32
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pcap_adjust_snapshot(bpf_u_int32 linktype, bpf_u_int32 snaplen)
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{
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if (snaplen == 0 || snaplen > INT_MAX) {
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/*
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* Bogus snapshot length; use the maximum for this
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* link-layer type as a fallback.
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*
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* XXX - we don't clamp snapshot lengths that are
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* <= INT_MAX but > max_snaplen_for_dlt(linktype),
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* so a capture file could cause us to allocate
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* a Really Big Buffer.
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*/
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snaplen = max_snaplen_for_dlt(linktype);
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}
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return snaplen;
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}
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static pcap_t *(*check_headers[])(const uint8_t *, FILE *, u_int, char *, int *) = {
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pcap_check_header,
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pcap_ng_check_header
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};
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#define N_FILE_TYPES (sizeof check_headers / sizeof check_headers[0])
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#ifdef _WIN32
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static
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#endif
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pcap_t *
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pcap_fopen_offline_with_tstamp_precision(FILE *fp, u_int precision,
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char *errbuf)
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{
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register pcap_t *p;
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uint8_t magic[4];
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size_t amt_read;
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u_int i;
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int err;
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/*
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* Fail if we were passed a NULL fp.
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*
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* That shouldn't happen if we're opening with a path name, but
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* it could happen if buggy code is opening with a FILE * and
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* didn't bother to make sure the FILE * isn't null.
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*/
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if (fp == NULL) {
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snprintf(errbuf, PCAP_ERRBUF_SIZE,
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"Null FILE * pointer provided to savefile open routine");
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return (NULL);
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}
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/*
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* Read the first 4 bytes of the file; the network analyzer dump
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* file formats we support (pcap and pcapng), and several other
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* formats we might support in the future (such as snoop, DOS and
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* Windows Sniffer, and Microsoft Network Monitor) all have magic
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* numbers that are unique in their first 4 bytes.
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*/
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amt_read = fread(&magic, 1, sizeof(magic), fp);
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if (amt_read != sizeof(magic)) {
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if (ferror(fp)) {
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pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
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|
errno, "error reading dump file");
|
|
} else {
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
|
"truncated dump file; tried to read %zu file header bytes, only got %zu",
|
|
sizeof(magic), amt_read);
|
|
}
|
|
return (NULL);
|
|
}
|
|
|
|
/*
|
|
* Try all file types.
|
|
*/
|
|
for (i = 0; i < N_FILE_TYPES; i++) {
|
|
p = (*check_headers[i])(magic, fp, precision, errbuf, &err);
|
|
if (p != NULL) {
|
|
/* Yup, that's it. */
|
|
goto found;
|
|
}
|
|
if (err) {
|
|
/*
|
|
* Error trying to read the header.
|
|
*/
|
|
return (NULL);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Well, who knows what this mess is....
|
|
*/
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE, "unknown file format");
|
|
return (NULL);
|
|
|
|
found:
|
|
p->rfile = fp;
|
|
|
|
/* Padding only needed for live capture fcode */
|
|
p->fddipad = 0;
|
|
|
|
#if !defined(_WIN32) && !defined(MSDOS)
|
|
/*
|
|
* You can do "select()" and "poll()" on plain files on most
|
|
* platforms, and should be able to do so on pipes.
|
|
*
|
|
* You can't do "select()" on anything other than sockets in
|
|
* Windows, so, on Win32 systems, we don't have "selectable_fd".
|
|
*/
|
|
p->selectable_fd = fileno(fp);
|
|
#endif
|
|
|
|
p->can_set_rfmon_op = sf_cant_set_rfmon;
|
|
p->read_op = pcap_offline_read;
|
|
p->inject_op = sf_inject;
|
|
p->setfilter_op = install_bpf_program;
|
|
p->setdirection_op = sf_setdirection;
|
|
p->set_datalink_op = NULL; /* we don't support munging link-layer headers */
|
|
p->getnonblock_op = sf_getnonblock;
|
|
p->setnonblock_op = sf_setnonblock;
|
|
p->stats_op = sf_stats;
|
|
#ifdef _WIN32
|
|
p->stats_ex_op = sf_stats_ex;
|
|
p->setbuff_op = sf_setbuff;
|
|
p->setmode_op = sf_setmode;
|
|
p->setmintocopy_op = sf_setmintocopy;
|
|
p->getevent_op = sf_getevent;
|
|
p->oid_get_request_op = sf_oid_get_request;
|
|
p->oid_set_request_op = sf_oid_set_request;
|
|
p->sendqueue_transmit_op = sf_sendqueue_transmit;
|
|
p->setuserbuffer_op = sf_setuserbuffer;
|
|
p->live_dump_op = sf_live_dump;
|
|
p->live_dump_ended_op = sf_live_dump_ended;
|
|
p->get_airpcap_handle_op = sf_get_airpcap_handle;
|
|
#endif
|
|
|
|
/*
|
|
* For offline captures, the standard one-shot callback can
|
|
* be used for pcap_next()/pcap_next_ex().
|
|
*/
|
|
p->oneshot_callback = pcap_oneshot;
|
|
|
|
/*
|
|
* Default breakloop operation.
|
|
*/
|
|
p->breakloop_op = pcap_breakloop_common;
|
|
|
|
/*
|
|
* Savefiles never require special BPF code generation.
|
|
*/
|
|
p->bpf_codegen_flags = 0;
|
|
|
|
p->activated = 1;
|
|
|
|
return (p);
|
|
}
|
|
|
|
/*
|
|
* This isn't needed on Windows; we #define pcap_fopen_offline() as
|
|
* a wrapper around pcap_hopen_offline(), and we don't call it from
|
|
* inside this file, so it's unused.
|
|
*/
|
|
#ifndef _WIN32
|
|
pcap_t *
|
|
pcap_fopen_offline(FILE *fp, char *errbuf)
|
|
{
|
|
return (pcap_fopen_offline_with_tstamp_precision(fp,
|
|
PCAP_TSTAMP_PRECISION_MICRO, errbuf));
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Read packets from a capture file, and call the callback for each
|
|
* packet.
|
|
* If cnt > 0, return after 'cnt' packets, otherwise continue until eof.
|
|
*/
|
|
int
|
|
pcap_offline_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
|
|
{
|
|
struct bpf_insn *fcode;
|
|
int n = 0;
|
|
u_char *data;
|
|
|
|
/*
|
|
* This can conceivably process more than INT_MAX packets,
|
|
* which would overflow the packet count, causing it either
|
|
* to look like a negative number, and thus cause us to
|
|
* return a value that looks like an error, or overflow
|
|
* back into positive territory, and thus cause us to
|
|
* return a too-low count.
|
|
*
|
|
* Therefore, if the packet count is unlimited, we clip
|
|
* it at INT_MAX; this routine is not expected to
|
|
* process packets indefinitely, so that's not an issue.
|
|
*/
|
|
if (PACKET_COUNT_IS_UNLIMITED(cnt))
|
|
cnt = INT_MAX;
|
|
|
|
for (;;) {
|
|
struct pcap_pkthdr h;
|
|
int status;
|
|
|
|
/*
|
|
* Has "pcap_breakloop()" been called?
|
|
* If so, return immediately - if we haven't read any
|
|
* packets, clear the flag and return -2 to indicate
|
|
* that we were told to break out of the loop, otherwise
|
|
* leave the flag set, so that the *next* call will break
|
|
* out of the loop without having read any packets, and
|
|
* return the number of packets we've processed so far.
|
|
*/
|
|
if (p->break_loop) {
|
|
if (n == 0) {
|
|
p->break_loop = 0;
|
|
return (-2);
|
|
} else
|
|
return (n);
|
|
}
|
|
|
|
status = p->next_packet_op(p, &h, &data);
|
|
if (status < 0) {
|
|
/*
|
|
* Error. Pass it back to the caller.
|
|
*/
|
|
return (status);
|
|
}
|
|
if (status == 0) {
|
|
/*
|
|
* EOF. Nothing more to process;
|
|
*/
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* OK, we've read a packet; run it through the filter
|
|
* and, if it passes, process it.
|
|
*/
|
|
if ((fcode = p->fcode.bf_insns) == NULL ||
|
|
pcap_filter(fcode, data, h.len, h.caplen)) {
|
|
(*callback)(user, &h, data);
|
|
n++; /* count the packet */
|
|
if (n >= cnt)
|
|
break;
|
|
}
|
|
}
|
|
/*XXX this breaks semantics tcpslice expects */
|
|
return (n);
|
|
}
|