savefile.c revision 75107
117683Spst/* 239291Sfenner * Copyright (c) 1993, 1994, 1995, 1996, 1997 317683Spst * The Regents of the University of California. All rights reserved. 417683Spst * 517683Spst * Redistribution and use in source and binary forms, with or without 617683Spst * modification, are permitted provided that: (1) source code distributions 717683Spst * retain the above copyright notice and this paragraph in its entirety, (2) 817683Spst * distributions including binary code include the above copyright notice and 917683Spst * this paragraph in its entirety in the documentation or other materials 1017683Spst * provided with the distribution, and (3) all advertising materials mentioning 1117683Spst * features or use of this software display the following acknowledgement: 1217683Spst * ``This product includes software developed by the University of California, 1317683Spst * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of 1417683Spst * the University nor the names of its contributors may be used to endorse 1517683Spst * or promote products derived from this software without specific prior 1617683Spst * written permission. 1717683Spst * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 1817683Spst * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 1917683Spst * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 2026175Sfenner * 2117683Spst * savefile.c - supports offline use of tcpdump 2217683Spst * Extraction/creation by Jeffrey Mogul, DECWRL 2317683Spst * Modified by Steve McCanne, LBL. 2417683Spst * 2517683Spst * Used to save the received packet headers, after filtering, to 2617683Spst * a file, and then read them later. 2717683Spst * The first record in the file contains saved values for the machine 2817683Spst * dependent values so we can print the dump file on any architecture. 2917683Spst */ 3017683Spst 3126175Sfenner#ifndef lint 3226175Sfennerstatic const char rcsid[] = 3375107Sfenner "@(#) $Header: /tcpdump/master/libpcap/savefile.c,v 1.49 2000/12/21 10:29:23 guy Exp $ (LBL)"; 3426175Sfenner#endif 3526175Sfenner 3675107Sfenner#ifdef HAVE_CONFIG_H 3775107Sfenner#include "config.h" 3875107Sfenner#endif 3975107Sfenner 4017683Spst#include <sys/types.h> 4117683Spst#include <sys/time.h> 4217683Spst 4317683Spst#include <errno.h> 4417683Spst#include <memory.h> 4517683Spst#include <stdio.h> 4617683Spst#include <stdlib.h> 4775107Sfenner#include <string.h> 4817683Spst#include <unistd.h> 4917683Spst 5017683Spst#include "pcap-int.h" 5117683Spst 5217683Spst#ifdef HAVE_OS_PROTO_H 5317683Spst#include "os-proto.h" 5417683Spst#endif 5517683Spst 5617683Spst#define TCPDUMP_MAGIC 0xa1b2c3d4 5775107Sfenner#define PATCHED_TCPDUMP_MAGIC 0xa1b2cd34 5817683Spst 5917683Spst/* 6017683Spst * We use the "receiver-makes-right" approach to byte order, 6117683Spst * because time is at a premium when we are writing the file. 6217683Spst * In other words, the pcap_file_header and pcap_pkthdr, 6317683Spst * records are written in host byte order. 6417683Spst * Note that the packets are always written in network byte order. 6517683Spst * 6617683Spst * ntoh[ls] aren't sufficient because we might need to swap on a big-endian 6717683Spst * machine (if the file was written in little-end order). 6817683Spst */ 6917683Spst#define SWAPLONG(y) \ 7017683Spst((((y)&0xff)<<24) | (((y)&0xff00)<<8) | (((y)&0xff0000)>>8) | (((y)>>24)&0xff)) 7117683Spst#define SWAPSHORT(y) \ 7226175Sfenner ( (((y)&0xff)<<8) | ((u_short)((y)&0xff00)>>8) ) 7317683Spst 7417683Spst#define SFERR_TRUNC 1 7517683Spst#define SFERR_BADVERSION 2 7617683Spst#define SFERR_BADF 3 7717683Spst#define SFERR_EOF 4 /* not really an error, just a status */ 7817683Spst 7975107Sfenner/* 8075107Sfenner * We don't write DLT_* values to the capture file header, because 8175107Sfenner * they're not the same on all platforms. 8275107Sfenner * 8375107Sfenner * Unfortunately, the various flavors of BSD have not always used the same 8475107Sfenner * numerical values for the same data types, and various patches to 8575107Sfenner * libpcap for non-BSD OSes have added their own DLT_* codes for link 8675107Sfenner * layer encapsulation types seen on those OSes, and those codes have had, 8775107Sfenner * in some cases, values that were also used, on other platforms, for other 8875107Sfenner * link layer encapsulation types. 8975107Sfenner * 9075107Sfenner * This means that capture files of a type whose numerical DLT_* code 9175107Sfenner * means different things on different BSDs, or with different versions 9275107Sfenner * of libpcap, can't always be read on systems other than those like 9375107Sfenner * the one running on the machine on which the capture was made. 9475107Sfenner * 9575107Sfenner * Instead, we define here a set of LINKTYPE_* codes, and map DLT_* codes 9675107Sfenner * to LINKTYPE_* codes when writing a savefile header, and map LINKTYPE_* 9775107Sfenner * codes to DLT_* codes when reading a savefile header. 9875107Sfenner * 9975107Sfenner * For those DLT_* codes that have, as far as we know, the same values on 10075107Sfenner * all platforms (DLT_NULL through DLT_FDDI), we define LINKTYPE_xxx as 10175107Sfenner * DLT_xxx; that way, captures of those types can still be read by 10275107Sfenner * versions of libpcap that map LINKTYPE_* values to DLT_* values, and 10375107Sfenner * captures of those types written by versions of libpcap that map DLT_ 10475107Sfenner * values to LINKTYPE_ values can still be read by older versions 10575107Sfenner * of libpcap. 10675107Sfenner * 10775107Sfenner * The other LINKTYPE_* codes are given values starting at 100, in the 10875107Sfenner * hopes that no DLT_* code will be given one of those values. 10975107Sfenner * 11075107Sfenner * In order to ensure that a given LINKTYPE_* code's value will refer to 11175107Sfenner * the same encapsulation type on all platforms, you should not allocate 11275107Sfenner * a new LINKTYPE_* value without consulting "tcpdump-workers@tcpdump.org". 11375107Sfenner * The tcpdump developers will allocate a value for you, and will not 11475107Sfenner * subsequently allocate it to anybody else; that value will be added to 11575107Sfenner * the "pcap.h" in the tcpdump.org CVS repository, so that a future 11675107Sfenner * libpcap release will include it. 11775107Sfenner * 11875107Sfenner * You should, if possible, also contribute patches to libpcap and tcpdump 11975107Sfenner * to handle the new encapsulation type, so that they can also be checked 12075107Sfenner * into the tcpdump.org CVS repository and so that they will appear in 12175107Sfenner * future libpcap and tcpdump releases. 12275107Sfenner */ 12375107Sfenner#define LINKTYPE_NULL DLT_NULL 12475107Sfenner#define LINKTYPE_ETHERNET DLT_EN10MB /* also for 100Mb and up */ 12575107Sfenner#define LINKTYPE_EXP_ETHERNET DLT_EN3MB /* 3Mb experimental Ethernet */ 12675107Sfenner#define LINKTYPE_AX25 DLT_AX25 12775107Sfenner#define LINKTYPE_PRONET DLT_PRONET 12875107Sfenner#define LINKTYPE_CHAOS DLT_CHAOS 12975107Sfenner#define LINKTYPE_TOKEN_RING DLT_IEEE802 /* DLT_IEEE802 is used for Token Ring */ 13075107Sfenner#define LINKTYPE_ARCNET DLT_ARCNET 13175107Sfenner#define LINKTYPE_SLIP DLT_SLIP 13275107Sfenner#define LINKTYPE_PPP DLT_PPP 13375107Sfenner#define LINKTYPE_FDDI DLT_FDDI 13475107Sfenner 13575107Sfenner/* 13675107Sfenner * LINKTYPE_PPP is for use when there might, or might not, be an RFC 1662 13775107Sfenner * PPP in HDLC-like framing header (with 0xff 0x03 before the PPP protocol 13875107Sfenner * field) at the beginning of the packet. 13975107Sfenner * 14075107Sfenner * This is for use when there is always such a header; the address field 14175107Sfenner * might be 0xff, for regular PPP, or it might be an address field for Cisco 14275107Sfenner * point-to-point with HDLC framing as per section 4.3.1 of RFC 1547 ("Cisco 14375107Sfenner * HDLC"). This is, for example, what you get with NetBSD's DLT_PPP_SERIAL. 14475107Sfenner * 14575107Sfenner * We give it the same value as NetBSD's DLT_PPP_SERIAL, in the hopes that 14675107Sfenner * nobody else will choose a DLT_ value of 50, and so that DLT_PPP_SERIAL 14775107Sfenner * captures will be written out with a link type that NetBSD's tcpdump 14875107Sfenner * can read. 14975107Sfenner */ 15075107Sfenner#define LINKTYPE_PPP_HDLC 50 /* PPP in HDLC-like framing */ 15175107Sfenner 15275107Sfenner#define LINKTYPE_ATM_RFC1483 100 /* LLC/SNAP-encapsulated ATM */ 15375107Sfenner#define LINKTYPE_RAW 101 /* raw IP */ 15475107Sfenner#define LINKTYPE_SLIP_BSDOS 102 /* BSD/OS SLIP BPF header */ 15575107Sfenner#define LINKTYPE_PPP_BSDOS 103 /* BSD/OS PPP BPF header */ 15675107Sfenner#define LINKTYPE_C_HDLC 104 /* Cisco HDLC */ 15775107Sfenner#define LINKTYPE_ATM_CLIP 106 /* Linux Classical IP over ATM */ 15875107Sfenner 15975107Sfenner/* 16075107Sfenner * Reserved for future use. 16175107Sfenner */ 16275107Sfenner#define LINKTYPE_IEEE802_11 105 /* IEEE 802.11 (wireless) */ 16375107Sfenner#define LINKTYPE_FR 107 /* BSD/OS Frame Relay */ 16475107Sfenner#define LINKTYPE_LOOP 108 /* OpenBSD loopback */ 16575107Sfenner#define LINKTYPE_ENC 109 /* OpenBSD IPSEC enc */ 16675107Sfenner#define LINKTYPE_LANE8023 110 /* ATM LANE + 802.3 */ 16775107Sfenner#define LINKTYPE_HIPPI 111 /* NetBSD HIPPI */ 16875107Sfenner#define LINKTYPE_HDLC 112 /* NetBSD HDLC framing */ 16975107Sfenner 17075107Sfenner#define LINKTYPE_LINUX_SLL 113 /* Linux cooked socket capture */ 17175107Sfenner 17275107Sfennerstatic struct linktype_map { 17375107Sfenner int dlt; 17475107Sfenner int linktype; 17575107Sfenner} map[] = { 17675107Sfenner /* 17775107Sfenner * These DLT_* codes have LINKTYPE_* codes with values identical 17875107Sfenner * to the values of the corresponding DLT_* code. 17975107Sfenner */ 18075107Sfenner { DLT_NULL, LINKTYPE_NULL }, 18175107Sfenner { DLT_EN10MB, LINKTYPE_ETHERNET }, 18275107Sfenner { DLT_EN3MB, LINKTYPE_EXP_ETHERNET }, 18375107Sfenner { DLT_AX25, LINKTYPE_AX25 }, 18475107Sfenner { DLT_PRONET, LINKTYPE_PRONET }, 18575107Sfenner { DLT_CHAOS, LINKTYPE_CHAOS }, 18675107Sfenner { DLT_IEEE802, LINKTYPE_TOKEN_RING }, 18775107Sfenner { DLT_ARCNET, LINKTYPE_ARCNET }, 18875107Sfenner { DLT_SLIP, LINKTYPE_SLIP }, 18975107Sfenner { DLT_PPP, LINKTYPE_PPP }, 19075107Sfenner { DLT_FDDI, LINKTYPE_FDDI }, 19175107Sfenner 19275107Sfenner /* 19375107Sfenner * These DLT_* codes have different values on different 19475107Sfenner * platforms; we map them to LINKTYPE_* codes that 19575107Sfenner * have values that should never be equal to any DLT_* 19675107Sfenner * code. 19775107Sfenner */ 19875107Sfenner { DLT_ATM_RFC1483, LINKTYPE_ATM_RFC1483 }, 19975107Sfenner { DLT_RAW, LINKTYPE_RAW }, 20075107Sfenner { DLT_SLIP_BSDOS, LINKTYPE_SLIP_BSDOS }, 20175107Sfenner { DLT_PPP_BSDOS, LINKTYPE_PPP_BSDOS }, 20275107Sfenner 20375107Sfenner /* BSD/OS Cisco HDLC */ 20475107Sfenner { DLT_C_HDLC, LINKTYPE_C_HDLC }, 20575107Sfenner 20675107Sfenner /* 20775107Sfenner * These DLT_* codes are not on all platforms, but, so far, 20875107Sfenner * there don't appear to be any platforms that define 20975107Sfenner * other codes with those values; we map them to 21075107Sfenner * different LINKTYPE_* values anyway, just in case. 21175107Sfenner */ 21275107Sfenner 21375107Sfenner /* Linux ATM Classical IP */ 21475107Sfenner { DLT_ATM_CLIP, LINKTYPE_ATM_CLIP }, 21575107Sfenner 21675107Sfenner /* NetBSD sync/async serial PPP (or Cisco HDLC) */ 21775107Sfenner { DLT_PPP_SERIAL, LINKTYPE_PPP_HDLC }, 21875107Sfenner 21975107Sfenner /* IEEE 802.11 wireless */ 22075107Sfenner { DLT_IEEE802_11, LINKTYPE_IEEE802_11 }, 22175107Sfenner 22275107Sfenner /* OpenBSD loopback */ 22375107Sfenner { DLT_LOOP, LINKTYPE_LOOP }, 22475107Sfenner 22575107Sfenner /* Linux cooked socket capture */ 22675107Sfenner { DLT_LINUX_SLL, LINKTYPE_LINUX_SLL }, 22775107Sfenner 22875107Sfenner /* 22975107Sfenner * Any platform that defines additional DLT_* codes should: 23075107Sfenner * 23175107Sfenner * request a LINKTYPE_* code and value from tcpdump.org, 23275107Sfenner * as per the above; 23375107Sfenner * 23475107Sfenner * add, in their version of libpcap, an entry to map 23575107Sfenner * those DLT_* codes to the corresponding LINKTYPE_* 23675107Sfenner * code; 23775107Sfenner * 23875107Sfenner * redefine, in their "net/bpf.h", any DLT_* values 23975107Sfenner * that collide with the values used by their additional 24075107Sfenner * DLT_* codes, to remove those collisions (but without 24175107Sfenner * making them collide with any of the LINKTYPE_* 24275107Sfenner * values equal to 50 or above; they should also avoid 24375107Sfenner * defining DLT_* values that collide with those 24475107Sfenner * LINKTYPE_* values, either). 24575107Sfenner */ 24675107Sfenner { -1, -1 } 24775107Sfenner}; 24875107Sfenner 24917683Spststatic int 25075107Sfennerdlt_to_linktype(int dlt) 25175107Sfenner{ 25275107Sfenner int i; 25375107Sfenner 25475107Sfenner for (i = 0; map[i].dlt != -1; i++) { 25575107Sfenner if (map[i].dlt == dlt) 25675107Sfenner return (map[i].linktype); 25775107Sfenner } 25875107Sfenner 25975107Sfenner /* 26075107Sfenner * If we don't have a mapping for this DLT_ code, return an 26175107Sfenner * error; that means that the table above needs to have an 26275107Sfenner * entry added. 26375107Sfenner */ 26475107Sfenner return (-1); 26575107Sfenner} 26675107Sfenner 26775107Sfennerstatic int 26875107Sfennerlinktype_to_dlt(int linktype) 26975107Sfenner{ 27075107Sfenner int i; 27175107Sfenner 27275107Sfenner for (i = 0; map[i].linktype != -1; i++) { 27375107Sfenner if (map[i].linktype == linktype) 27475107Sfenner return (map[i].dlt); 27575107Sfenner } 27675107Sfenner 27775107Sfenner /* 27875107Sfenner * If we don't have an entry for this link type, return 27975107Sfenner * the link type value; it may be a DLT_ value from an 28075107Sfenner * older version of libpcap. 28175107Sfenner */ 28275107Sfenner return linktype; 28375107Sfenner} 28475107Sfenner 28575107Sfennerstatic int 28617683Spstsf_write_header(FILE *fp, int linktype, int thiszone, int snaplen) 28717683Spst{ 28817683Spst struct pcap_file_header hdr; 28917683Spst 29017683Spst hdr.magic = TCPDUMP_MAGIC; 29117683Spst hdr.version_major = PCAP_VERSION_MAJOR; 29217683Spst hdr.version_minor = PCAP_VERSION_MINOR; 29317683Spst 29417683Spst hdr.thiszone = thiszone; 29517683Spst hdr.snaplen = snaplen; 29617683Spst hdr.sigfigs = 0; 29717683Spst hdr.linktype = linktype; 29817683Spst 29917683Spst if (fwrite((char *)&hdr, sizeof(hdr), 1, fp) != 1) 30017683Spst return (-1); 30117683Spst 30217683Spst return (0); 30317683Spst} 30417683Spst 30517683Spststatic void 30617683Spstswap_hdr(struct pcap_file_header *hp) 30717683Spst{ 30817683Spst hp->version_major = SWAPSHORT(hp->version_major); 30917683Spst hp->version_minor = SWAPSHORT(hp->version_minor); 31017683Spst hp->thiszone = SWAPLONG(hp->thiszone); 31117683Spst hp->sigfigs = SWAPLONG(hp->sigfigs); 31217683Spst hp->snaplen = SWAPLONG(hp->snaplen); 31317683Spst hp->linktype = SWAPLONG(hp->linktype); 31417683Spst} 31517683Spst 31617683Spstpcap_t * 31739291Sfennerpcap_open_offline(const char *fname, char *errbuf) 31817683Spst{ 31917683Spst register pcap_t *p; 32017683Spst register FILE *fp; 32117683Spst struct pcap_file_header hdr; 32275107Sfenner bpf_u_int32 magic; 32317683Spst int linklen; 32417683Spst 32517683Spst p = (pcap_t *)malloc(sizeof(*p)); 32617683Spst if (p == NULL) { 32775107Sfenner strlcpy(errbuf, "out of swap", PCAP_ERRBUF_SIZE); 32817683Spst return (NULL); 32917683Spst } 33017683Spst 33117683Spst memset((char *)p, 0, sizeof(*p)); 33217683Spst /* 33317683Spst * Set this field so we don't close stdin in pcap_close! 33417683Spst */ 33517683Spst p->fd = -1; 33617683Spst 33717683Spst if (fname[0] == '-' && fname[1] == '\0') 33817683Spst fp = stdin; 33917683Spst else { 34017683Spst fp = fopen(fname, "r"); 34117683Spst if (fp == NULL) { 34275107Sfenner snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s", fname, 34375107Sfenner pcap_strerror(errno)); 34417683Spst goto bad; 34517683Spst } 34617683Spst } 34717683Spst if (fread((char *)&hdr, sizeof(hdr), 1, fp) != 1) { 34875107Sfenner snprintf(errbuf, PCAP_ERRBUF_SIZE, "fread: %s", 34975107Sfenner pcap_strerror(errno)); 35017683Spst goto bad; 35117683Spst } 35275107Sfenner magic = hdr.magic; 35375107Sfenner if (magic != TCPDUMP_MAGIC && magic != PATCHED_TCPDUMP_MAGIC) { 35475107Sfenner magic = SWAPLONG(magic); 35575107Sfenner if (magic != TCPDUMP_MAGIC && magic != PATCHED_TCPDUMP_MAGIC) { 35675107Sfenner snprintf(errbuf, PCAP_ERRBUF_SIZE, 35775107Sfenner "bad dump file format"); 35817683Spst goto bad; 35917683Spst } 36017683Spst p->sf.swapped = 1; 36117683Spst swap_hdr(&hdr); 36217683Spst } 36375107Sfenner if (magic == PATCHED_TCPDUMP_MAGIC) { 36475107Sfenner /* 36575107Sfenner * XXX - the patch that's in some versions of libpcap 36675107Sfenner * changes the packet header but not the magic number; 36775107Sfenner * we'd have to use some hacks^H^H^H^H^Hheuristics to 36875107Sfenner * detect that. 36975107Sfenner */ 37075107Sfenner p->sf.hdrsize = sizeof(struct pcap_sf_patched_pkthdr); 37175107Sfenner } else 37275107Sfenner p->sf.hdrsize = sizeof(struct pcap_sf_pkthdr); 37317683Spst if (hdr.version_major < PCAP_VERSION_MAJOR) { 37475107Sfenner snprintf(errbuf, PCAP_ERRBUF_SIZE, "archaic file format"); 37517683Spst goto bad; 37617683Spst } 37717683Spst p->tzoff = hdr.thiszone; 37817683Spst p->snapshot = hdr.snaplen; 37975107Sfenner p->linktype = linktype_to_dlt(hdr.linktype); 38017683Spst p->sf.rfile = fp; 38117683Spst p->bufsize = hdr.snaplen; 38217683Spst 38317683Spst /* Align link header as required for proper data alignment */ 38417683Spst /* XXX should handle all types */ 38517683Spst switch (p->linktype) { 38617683Spst 38717683Spst case DLT_EN10MB: 38817683Spst linklen = 14; 38917683Spst break; 39017683Spst 39117683Spst case DLT_FDDI: 39217683Spst linklen = 13 + 8; /* fddi_header + llc */ 39317683Spst break; 39417683Spst 39517683Spst case DLT_NULL: 39617683Spst default: 39717683Spst linklen = 0; 39817683Spst break; 39917683Spst } 40017683Spst 40175107Sfenner if (p->bufsize < 0) 40275107Sfenner p->bufsize = BPF_MAXBUFSIZE; 40317683Spst p->sf.base = (u_char *)malloc(p->bufsize + BPF_ALIGNMENT); 40475107Sfenner if (p->sf.base == NULL) { 40575107Sfenner strlcpy(errbuf, "out of swap", PCAP_ERRBUF_SIZE); 40675107Sfenner goto bad; 40775107Sfenner } 40817683Spst p->buffer = p->sf.base + BPF_ALIGNMENT - (linklen % BPF_ALIGNMENT); 40917683Spst p->sf.version_major = hdr.version_major; 41017683Spst p->sf.version_minor = hdr.version_minor; 41117683Spst#ifdef PCAP_FDDIPAD 41217683Spst /* XXX padding only needed for kernel fcode */ 41317683Spst pcap_fddipad = 0; 41417683Spst#endif 41517683Spst 41617683Spst return (p); 41717683Spst bad: 41817683Spst free(p); 41917683Spst return (NULL); 42017683Spst} 42117683Spst 42217683Spst/* 42317683Spst * Read sf_readfile and return the next packet. Return the header in hdr 42417683Spst * and the contents in buf. Return 0 on success, SFERR_EOF if there were 42517683Spst * no more packets, and SFERR_TRUNC if a partial packet was encountered. 42617683Spst */ 42717683Spststatic int 42817683Spstsf_next_packet(pcap_t *p, struct pcap_pkthdr *hdr, u_char *buf, int buflen) 42917683Spst{ 43075107Sfenner struct pcap_sf_patched_pkthdr sf_hdr; 43117683Spst FILE *fp = p->sf.rfile; 43217683Spst 43375107Sfenner /* 43475107Sfenner * Read the packet header; the structure we use as a buffer 43575107Sfenner * is the longer structure for files generated by the patched 43675107Sfenner * libpcap, but if the file has the magic number for an 43775107Sfenner * unpatched libpcap we only read as many bytes as the regular 43875107Sfenner * header has. 43975107Sfenner */ 44075107Sfenner if (fread(&sf_hdr, p->sf.hdrsize, 1, fp) != 1) { 44117683Spst /* probably an EOF, though could be a truncated packet */ 44217683Spst return (1); 44317683Spst } 44417683Spst 44517683Spst if (p->sf.swapped) { 44617683Spst /* these were written in opposite byte order */ 44756889Sfenner hdr->caplen = SWAPLONG(sf_hdr.caplen); 44856889Sfenner hdr->len = SWAPLONG(sf_hdr.len); 44956889Sfenner hdr->ts.tv_sec = SWAPLONG(sf_hdr.ts.tv_sec); 45056889Sfenner hdr->ts.tv_usec = SWAPLONG(sf_hdr.ts.tv_usec); 45156889Sfenner } else { 45256889Sfenner hdr->caplen = sf_hdr.caplen; 45356889Sfenner hdr->len = sf_hdr.len; 45456889Sfenner hdr->ts.tv_sec = sf_hdr.ts.tv_sec; 45556889Sfenner hdr->ts.tv_usec = sf_hdr.ts.tv_usec; 45617683Spst } 45717683Spst /* 45817683Spst * We interchanged the caplen and len fields at version 2.3, 45917683Spst * in order to match the bpf header layout. But unfortunately 46017683Spst * some files were written with version 2.3 in their headers 46117683Spst * but without the interchanged fields. 46217683Spst */ 46317683Spst if (p->sf.version_minor < 3 || 46417683Spst (p->sf.version_minor == 3 && hdr->caplen > hdr->len)) { 46517683Spst int t = hdr->caplen; 46617683Spst hdr->caplen = hdr->len; 46717683Spst hdr->len = t; 46817683Spst } 46917683Spst 47017683Spst if (hdr->caplen > buflen) { 47117683Spst /* 47217683Spst * This can happen due to Solaris 2.3 systems tripping 47317683Spst * over the BUFMOD problem and not setting the snapshot 47417683Spst * correctly in the savefile header. If the caplen isn't 47517683Spst * grossly wrong, try to salvage. 47617683Spst */ 47717683Spst static u_char *tp = NULL; 47817683Spst static int tsize = 0; 47917683Spst 48026175Sfenner if (hdr->caplen > 65535) { 48175107Sfenner snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 48275107Sfenner "bogus savefile header"); 48326175Sfenner return (-1); 48426175Sfenner } 48575107Sfenner 48617683Spst if (tsize < hdr->caplen) { 48717683Spst tsize = ((hdr->caplen + 1023) / 1024) * 1024; 48817683Spst if (tp != NULL) 48917683Spst free((u_char *)tp); 49017683Spst tp = (u_char *)malloc(tsize); 49117683Spst if (tp == NULL) { 49226175Sfenner tsize = 0; 49375107Sfenner snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 49475107Sfenner "BUFMOD hack malloc"); 49517683Spst return (-1); 49617683Spst } 49717683Spst } 49817683Spst if (fread((char *)tp, hdr->caplen, 1, fp) != 1) { 49975107Sfenner snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 50075107Sfenner "truncated dump file"); 50117683Spst return (-1); 50217683Spst } 50326175Sfenner /* 50426175Sfenner * We can only keep up to buflen bytes. Since caplen > buflen 50526175Sfenner * is exactly how we got here, we know we can only keep the 50626175Sfenner * first buflen bytes and must drop the remainder. Adjust 50726175Sfenner * caplen accordingly, so we don't get confused later as 50826175Sfenner * to how many bytes we have to play with. 50926175Sfenner */ 51026175Sfenner hdr->caplen = buflen; 51117683Spst memcpy((char *)buf, (char *)tp, buflen); 51217683Spst 51317683Spst } else { 51417683Spst /* read the packet itself */ 51517683Spst 51617683Spst if (fread((char *)buf, hdr->caplen, 1, fp) != 1) { 51775107Sfenner snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 51875107Sfenner "truncated dump file"); 51917683Spst return (-1); 52017683Spst } 52117683Spst } 52217683Spst return (0); 52317683Spst} 52417683Spst 52517683Spst/* 52617683Spst * Print out packets stored in the file initialized by sf_read_init(). 52717683Spst * If cnt > 0, return after 'cnt' packets, otherwise continue until eof. 52817683Spst */ 52917683Spstint 53017683Spstpcap_offline_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user) 53117683Spst{ 53217683Spst struct bpf_insn *fcode = p->fcode.bf_insns; 53317683Spst int status = 0; 53417683Spst int n = 0; 53517683Spst 53617683Spst while (status == 0) { 53717683Spst struct pcap_pkthdr h; 53817683Spst 53917683Spst status = sf_next_packet(p, &h, p->buffer, p->bufsize); 54017683Spst if (status) { 54117683Spst if (status == 1) 54217683Spst return (0); 54317683Spst return (status); 54417683Spst } 54517683Spst 54617683Spst if (fcode == NULL || 54717683Spst bpf_filter(fcode, p->buffer, h.len, h.caplen)) { 54817683Spst (*callback)(user, &h, p->buffer); 54917683Spst if (++n >= cnt && cnt > 0) 55017683Spst break; 55117683Spst } 55217683Spst } 55317683Spst /*XXX this breaks semantics tcpslice expects */ 55417683Spst return (n); 55517683Spst} 55617683Spst 55717683Spst/* 55817683Spst * Output a packet to the initialized dump file. 55917683Spst */ 56017683Spstvoid 56117683Spstpcap_dump(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) 56217683Spst{ 56317683Spst register FILE *f; 56456889Sfenner struct pcap_sf_pkthdr sf_hdr; 56517683Spst 56617683Spst f = (FILE *)user; 56756889Sfenner sf_hdr.ts.tv_sec = h->ts.tv_sec; 56856889Sfenner sf_hdr.ts.tv_usec = h->ts.tv_usec; 56956889Sfenner sf_hdr.caplen = h->caplen; 57056889Sfenner sf_hdr.len = h->len; 57117683Spst /* XXX we should check the return status */ 57256889Sfenner (void)fwrite(&sf_hdr, sizeof(sf_hdr), 1, f); 57317683Spst (void)fwrite((char *)sp, h->caplen, 1, f); 57417683Spst} 57517683Spst 57617683Spst/* 57717683Spst * Initialize so that sf_write() will output to the file named 'fname'. 57817683Spst */ 57917683Spstpcap_dumper_t * 58039291Sfennerpcap_dump_open(pcap_t *p, const char *fname) 58117683Spst{ 58217683Spst FILE *f; 58375107Sfenner int linktype; 58475107Sfenner 58575107Sfenner linktype = dlt_to_linktype(p->linktype); 58675107Sfenner if (linktype == -1) { 58775107Sfenner snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 58875107Sfenner "%s: link-layer type %d isn't supported in savefiles", 58975107Sfenner fname, linktype); 59075107Sfenner return (NULL); 59175107Sfenner } 59275107Sfenner 59317683Spst if (fname[0] == '-' && fname[1] == '\0') 59417683Spst f = stdout; 59517683Spst else { 59617683Spst f = fopen(fname, "w"); 59717683Spst if (f == NULL) { 59875107Sfenner snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "%s: %s", 59917683Spst fname, pcap_strerror(errno)); 60017683Spst return (NULL); 60117683Spst } 60217683Spst } 60375107Sfenner (void)sf_write_header(f, linktype, p->tzoff, p->snapshot); 60417683Spst return ((pcap_dumper_t *)f); 60517683Spst} 60617683Spst 60717683Spstvoid 60817683Spstpcap_dump_close(pcap_dumper_t *p) 60917683Spst{ 61017683Spst 61117683Spst#ifdef notyet 61217683Spst if (ferror((FILE *)p)) 61317683Spst return-an-error; 61417683Spst /* XXX should check return from fclose() too */ 61517683Spst#endif 61617683Spst (void)fclose((FILE *)p); 61717683Spst} 618