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# pcap.c

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    00001 /*
    00002  * Copyright (c) 1993, 1994, 1995, 1996, 1997, 1998
    00003  *  The Regents of the University of California.  All rights reserved.
    00004  *
    00005  * Redistribution and use in source and binary forms, with or without
    00006  * modification, are permitted provided that the following conditions
    00007  * are met:
    00008  * 1. Redistributions of source code must retain the above copyright
    00009  *    notice, this list of conditions and the following disclaimer.
    00010  * 2. Redistributions in binary form must reproduce the above copyright
    00011  *    notice, this list of conditions and the following disclaimer in the
    00012  *    documentation and/or other materials provided with the distribution.
    00013  * 3. All advertising materials mentioning features or use of this software
    00014  *    must display the following acknowledgement:
    00015  *  This product includes software developed by the Computer Systems
    00016  *  Engineering Group at Lawrence Berkeley Laboratory.
    00017  * 4. Neither the name of the University nor of the Laboratory may be used
    00018  *    to endorse or promote products derived from this software without
    00019  *    specific prior written permission.
    00020  *
    00021  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
    00022  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    00023  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    00024  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
    00025  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
    00026  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
    00027  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
    00028  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
    00029  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
    00030  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
    00031  * SUCH DAMAGE.
    00032  */
    00033
    00034 #ifndef lint
    00035 static const char rcsid[] _U_ =
    00036     "@(#) $Header: /tcpdump/master/libpcap/pcap.c,v 1.70 2003/12/18 23:32:34 guy Exp $ (LBL)";
    00037 #endif
    00038
    00039 #ifdef HAVE_CONFIG_H
    00040 #include "config.h"
    00041 #endif
    00042
    00043 #ifdef WIN32
    00044 #include <pcap-stdinc.h>
    00045 #else /* WIN32 */
    00046 #include <sys/types.h>
    00047 #endif /* WIN32 */
    00048
    00049 #include <stdio.h>
    00050 #include <stdlib.h>
    00051 #include <string.h>
    00052 #ifndef WIN32
    00053 #include <unistd.h>
    00054 #endif
    00055 #include <fcntl.h>
    00056 #include <errno.h>
    00057
    00058 #ifdef HAVE_OS_PROTO_H
    00059 #include "os-proto.h"
    00060 #endif
    00061
    00062 #include "pcap-int.h"
    00063
    00064 #ifdef HAVE_DAG_API
    00065 #include <dagnew.h>
    00066 #include <dagapi.h>
    00067 #endif
    00068
    00069 #ifdef HAVE_REMOTE
    00070 #include <pcap-remote.h>
    00071 #endif
    00072
    00073
    00074 int
    00075 pcap_dispatch(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
    00076 {
    00077
    00078     return p->read_op(p, cnt, callback, user);
    00079 }
    00080
    00081 /*
    00082  * XXX - is this necessary?
    00083  */
    00084 int
    00085 pcap_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
    00086 {
    00087
    00088     return p->read_op(p, cnt, callback, user);
    00089 }
    00090
    00091 int
    00092 pcap_loop(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
    00093 {
    00094     register int n;
    00095
    00096     for (;;) {
    00097         if (p->sf.rfile != NULL) {
    00098             /*
    00099              * 0 means EOF, so don't loop if we get 0.
    00100              */
    00101             n = pcap_offline_read(p, cnt, callback, user);
    00102         } else {
    00103             /*
    00104              * XXX keep reading until we get something
    00105              * (or an error occurs)
    00106              */
    00107             do {
    00108                 n = p->read_op(p, cnt, callback, user);
    00109             } while (n == 0);
    00110         }
    00111         if (n <= 0)
    00112             return (n);
    00113         if (cnt > 0) {
    00114             cnt -= n;
    00115             if (cnt <= 0)
    00116                 return (0);
    00117         }
    00118     }
    00119 }
    00120
    00121 struct singleton {
    00122     struct pcap_pkthdr *hdr;
    00123     const u_char *pkt;
    00124 };
    00125
    00126
    00127 static void
    00128 pcap_oneshot(u_char *userData, const struct pcap_pkthdr *h, const u_char *pkt)
    00129 {
    00130     struct singleton *sp = (struct singleton *)userData;
    00131     *sp->hdr = *h;
    00132     sp->pkt = pkt;
    00133 }
    00134
    00135 const u_char *
    00136 pcap_next(pcap_t *p, struct pcap_pkthdr *h)
    00137 {
    00138     struct singleton s;
    00139
    00140     s.hdr = h;
    00141     if (pcap_dispatch(p, 1, pcap_oneshot, (u_char*)&s) <= 0)
    00142         return (0);
    00143     return (s.pkt);
    00144 }
    00145
    00146 struct pkt_for_fakecallback {
    00147     struct pcap_pkthdr *hdr;
    00148     const u_char **pkt;
    00149 };
    00150
    00151 static void
    00152 pcap_fakecallback(u_char *userData, const struct pcap_pkthdr *h,
    00153     const u_char *pkt)
    00154 {
    00155     struct pkt_for_fakecallback *sp = (struct pkt_for_fakecallback *)userData;
    00156
    00157     *sp->hdr = *h;
    00158     *sp->pkt = pkt;
    00159 }
    00160
    00161 int
    00162 pcap_next_ex(pcap_t *p, struct pcap_pkthdr **pkt_header,
    00163     const u_char **pkt_data)
    00164 {
    00165     struct pkt_for_fakecallback s;
    00166
    00167     s.hdr = &p->pcap_header;
    00168     s.pkt = pkt_data;
    00169
    00170     /* Saves a pointer to the packet headers */
    00171     *pkt_header= &p->pcap_header;
    00172
    00173 #ifdef HAVE_REMOTE
    00174     /* Checks the capture type */
    00175     if (p->rmt_clientside)
    00176     {
    00177         /* We are on an remote capture */
    00178         if (!p->rmt_capstarted)
    00179         {
    00180             // if the capture has not started yet, please start it
    00181             if (pcap_startcapture_remote(p) )
    00182                 return -1;
    00183         }
    00184
    00185         return pcap_read_nocb_remote(p, pkt_header, (u_char **) pkt_data);
    00186     }
    00187 #endif /* HAVE_REMOTE */
    00188
    00189     if (p->sf.rfile != NULL) {
    00190         int status;
    00191
    00192         /* We are on an offline capture */
    00193         status = pcap_offline_read(p, 1, pcap_fakecallback,
    00194             (u_char *)&s);
    00195
    00196         /*
    00197          * Return codes for pcap_offline_read() are:
    00198          *   -  0: EOF
    00199          *   - -1: error
    00200          *   - >1: OK
    00201          * The first one ('0') conflicts with the return code of
    00202          * 0 from pcap_read() meaning "no packets arrived before
    00203          * the timeout expired", so we map it to -2 so you can
    00204          * distinguish between an EOF from a savefile and a
    00205          * "no packets arrived before the timeout expired, try
    00206          * again" from a live capture.
    00207          */
    00208         if (status == 0)
    00209             return (-2);
    00210         else
    00211             return (status);
    00212     }
    00213
    00214     /*
    00215      * Return codes for pcap_read() are:
    00216      *   -  0: timeout
    00217      *   - -1: error
    00218      *   - -2: loop was broken out of with pcap_breakloop()
    00219      *   - >1: OK
    00220      * The first one ('0') conflicts with the return code of 0 from
    00221      * pcap_offline_read() meaning "end of file".
    00222     */
    00223     return (p->read_op(p, 1, pcap_fakecallback, (u_char *)&s));
    00224 }
    00225
    00226 /*
    00227  * Force the loop in "pcap_read()" or "pcap_read_offline()" to terminate.
    00228  */
    00229 void
    00230 pcap_breakloop(pcap_t *p)
    00231 {
    00232     p->break_loop = 1;
    00233 }
    00234
    00235 int
    00236 pcap_datalink(pcap_t *p)
    00237 {
    00238     return (p->linktype);
    00239 }
    00240
    00241 int
    00242 pcap_list_datalinks(pcap_t *p, int **dlt_buffer)
    00243 {
    00244     if (p->dlt_count == 0) {
    00245         /*
    00246          * We couldn't fetch the list of DLTs, which means
    00247          * this platform doesn't support changing the
    00248          * DLT for an interface.  Return a list of DLTs
    00249          * containing only the DLT this device supports.
    00250          */
    00251         *dlt_buffer = (int*)malloc(sizeof(**dlt_buffer));
    00252         if (*dlt_buffer == NULL) {
    00253             (void)snprintf(p->errbuf, sizeof(p->errbuf),
    00254                 "malloc: %s", pcap_strerror(errno));
    00255             return (-1);
    00256         }
    00257         **dlt_buffer = p->linktype;
    00258         return (1);
    00259     } else {
    00260         *dlt_buffer = (int*)malloc(sizeof(**dlt_buffer) * p->dlt_count);
    00261         if (*dlt_buffer == NULL) {
    00262             (void)snprintf(p->errbuf, sizeof(p->errbuf),
    00263                 "malloc: %s", pcap_strerror(errno));
    00264             return (-1);
    00265         }
    00266         (void)memcpy(*dlt_buffer, p->dlt_list,
    00267             sizeof(**dlt_buffer) * p->dlt_count);
    00268         return (p->dlt_count);
    00269     }
    00270 }
    00271
    00272 int
    00273 pcap_set_datalink(pcap_t *p, int dlt)
    00274 {
    00275     int i;
    00276     const char *dlt_name;
    00277
    00278     if (p->dlt_count == 0 || p->set_datalink_op == NULL) {
    00279         /*
    00280          * We couldn't fetch the list of DLTs, or we don't
    00281          * have a "set datalink" operation, which means
    00282          * this platform doesn't support changing the
    00283          * DLT for an interface.  Check whether the new
    00284          * DLT is the one this interface supports.
    00285          */
    00286         if (p->linktype != dlt)
    00287             goto unsupported;
    00288
    00289         /*
    00290          * It is, so there's nothing we need to do here.
    00291          */
    00292         return (0);
    00293     }
    00294     for (i = 0; i < p->dlt_count; i++)
    00295         if (p->dlt_list[i] == dlt)
    00296             break;
    00297     if (i >= p->dlt_count)
    00298         goto unsupported;
    00299     if (p->dlt_count == 2 && p->dlt_list[0] == DLT_EN10MB &&
    00300         dlt == DLT_DOCSIS) {
    00301         /*
    00302          * This is presumably an Ethernet device, as the first
    00303          * link-layer type it offers is DLT_EN10MB, and the only
    00304          * other type it offers is DLT_DOCSIS.  That means that
    00305          * we can't tell the driver to supply DOCSIS link-layer
    00306          * headers - we're just pretending that's what we're
    00307          * getting, as, presumably, we're capturing on a dedicated
    00308          * link to a Cisco Cable Modem Termination System, and
    00309          * it's putting raw DOCSIS frames on the wire inside low-level
    00310          * Ethernet framing.
    00311          */
    00312         p->linktype = dlt;
    00313         return (0);
    00314     }
    00315     if (p->set_datalink_op(p, dlt) == -1)
    00316         return (-1);
    00317     p->linktype = dlt;
    00318     return (0);
    00319
    00320 unsupported:
    00321     dlt_name = pcap_datalink_val_to_name(dlt);
    00322     if (dlt_name != NULL) {
    00323         (void) snprintf(p->errbuf, sizeof(p->errbuf),
    00324             "%s is not one of the DLTs supported by this device",
    00325             dlt_name);
    00326     } else {
    00327         (void) snprintf(p->errbuf, sizeof(p->errbuf),
    00328             "DLT %d is not one of the DLTs supported by this device",
    00329             dlt);
    00330     }
    00331     return (-1);
    00332 }
    00333
    00334 struct dlt_choice {
    00335     const char *name;
    00336     const char *description;
    00337     int dlt;
    00338 };
    00339
    00340 #define DLT_CHOICE(code, description) { #code, description, code }
    00341 #define DLT_CHOICE_SENTINEL { NULL, NULL, 0 }
    00342
    00343 static struct dlt_choice dlt_choices[] = {
    00344     DLT_CHOICE(DLT_NULL, "BSD loopback"),
    00345     DLT_CHOICE(DLT_EN10MB, "Ethernet"),
    00346     DLT_CHOICE(DLT_IEEE802, "Token ring"),
    00347     DLT_CHOICE(DLT_ARCNET, "ARCNET"),
    00348     DLT_CHOICE(DLT_SLIP, "SLIP"),
    00349     DLT_CHOICE(DLT_PPP, "PPP"),
    00350     DLT_CHOICE(DLT_FDDI, "FDDI"),
    00351     DLT_CHOICE(DLT_ATM_RFC1483, "RFC 1483 IP-over-ATM"),
    00352     DLT_CHOICE(DLT_RAW, "Raw IP"),
    00353     DLT_CHOICE(DLT_SLIP_BSDOS, "BSD/OS SLIP"),
    00354     DLT_CHOICE(DLT_PPP_BSDOS, "BSD/OS PPP"),
    00355     DLT_CHOICE(DLT_ATM_CLIP, "Linux Classical IP-over-ATM"),
    00356     DLT_CHOICE(DLT_PPP_SERIAL, "PPP over serial"),
    00357     DLT_CHOICE(DLT_PPP_ETHER, "PPPoE"),
    00358     DLT_CHOICE(DLT_C_HDLC, "Cisco HDLC"),
    00359     DLT_CHOICE(DLT_IEEE802_11, "802.11"),
    00360     DLT_CHOICE(DLT_FRELAY, "Frame Relay"),
    00361     DLT_CHOICE(DLT_LOOP, "OpenBSD loopback"),
    00362     DLT_CHOICE(DLT_ENC, "OpenBSD encapsulated IP"),
    00363     DLT_CHOICE(DLT_LINUX_SLL, "Linux cooked"),
    00364     DLT_CHOICE(DLT_LTALK, "Localtalk"),
    00365     DLT_CHOICE(DLT_PFLOG, "OpenBSD pflog file"),
    00366     DLT_CHOICE(DLT_PRISM_HEADER, "802.11 plus Prism header"),
    00367     DLT_CHOICE(DLT_IP_OVER_FC, "RFC 2625 IP-over-Fibre Channel"),
    00368     DLT_CHOICE(DLT_SUNATM, "Sun raw ATM"),
    00369     DLT_CHOICE(DLT_IEEE802_11_RADIO, "802.11 plus radio information header"),
    00370     DLT_CHOICE(DLT_ARCNET_LINUX, "Linux ARCNET"),
    00371     DLT_CHOICE(DLT_DOCSIS, "DOCSIS"),
    00372     DLT_CHOICE(DLT_LINUX_IRDA, "Linux IrDA"),
    00373     DLT_CHOICE_SENTINEL
    00374 };
    00375
    00376 /*
    00377  * This array is designed for mapping upper and lower case letter
    00378  * together for a case independent comparison.  The mappings are
    00379  * based upon ascii character sequences.
    00380  */
    00381 static const u_char charmap[] = {
    00382     (u_char)'\000', (u_char)'\001', (u_char)'\002', (u_char)'\003',
    00383     (u_char)'\004', (u_char)'\005', (u_char)'\006', (u_char)'\007',
    00384     (u_char)'\010', (u_char)'\011', (u_char)'\012', (u_char)'\013',
    00385     (u_char)'\014', (u_char)'\015', (u_char)'\016', (u_char)'\017',
    00386     (u_char)'\020', (u_char)'\021', (u_char)'\022', (u_char)'\023',
    00387     (u_char)'\024', (u_char)'\025', (u_char)'\026', (u_char)'\027',
    00388     (u_char)'\030', (u_char)'\031', (u_char)'\032', (u_char)'\033',
    00389     (u_char)'\034', (u_char)'\035', (u_char)'\036', (u_char)'\037',
    00390     (u_char)'\040', (u_char)'\041', (u_char)'\042', (u_char)'\043',
    00391     (u_char)'\044', (u_char)'\045', (u_char)'\046', (u_char)'\047',
    00392     (u_char)'\050', (u_char)'\051', (u_char)'\052', (u_char)'\053',
    00393     (u_char)'\054', (u_char)'\055', (u_char)'\056', (u_char)'\057',
    00394     (u_char)'\060', (u_char)'\061', (u_char)'\062', (u_char)'\063',
    00395     (u_char)'\064', (u_char)'\065', (u_char)'\066', (u_char)'\067',
    00396     (u_char)'\070', (u_char)'\071', (u_char)'\072', (u_char)'\073',
    00397     (u_char)'\074', (u_char)'\075', (u_char)'\076', (u_char)'\077',
    00398     (u_char)'\100', (u_char)'\141', (u_char)'\142', (u_char)'\143',
    00399     (u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147',
    00400     (u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153',
    00401     (u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157',
    00402     (u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163',
    00403     (u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167',
    00404     (u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\133',
    00405     (u_char)'\134', (u_char)'\135', (u_char)'\136', (u_char)'\137',
    00406     (u_char)'\140', (u_char)'\141', (u_char)'\142', (u_char)'\143',
    00407     (u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147',
    00408     (u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153',
    00409     (u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157',
    00410     (u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163',
    00411     (u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167',
    00412     (u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\173',
    00413     (u_char)'\174', (u_char)'\175', (u_char)'\176', (u_char)'\177',
    00414     (u_char)'\200', (u_char)'\201', (u_char)'\202', (u_char)'\203',
    00415     (u_char)'\204', (u_char)'\205', (u_char)'\206', (u_char)'\207',
    00416     (u_char)'\210', (u_char)'\211', (u_char)'\212', (u_char)'\213',
    00417     (u_char)'\214', (u_char)'\215', (u_char)'\216', (u_char)'\217',
    00418     (u_char)'\220', (u_char)'\221', (u_char)'\222', (u_char)'\223',
    00419     (u_char)'\224', (u_char)'\225', (u_char)'\226', (u_char)'\227',
    00420     (u_char)'\230', (u_char)'\231', (u_char)'\232', (u_char)'\233',
    00421     (u_char)'\234', (u_char)'\235', (u_char)'\236', (u_char)'\237',
    00422     (u_char)'\240', (u_char)'\241', (u_char)'\242', (u_char)'\243',
    00423     (u_char)'\244', (u_char)'\245', (u_char)'\246', (u_char)'\247',
    00424     (u_char)'\250', (u_char)'\251', (u_char)'\252', (u_char)'\253',
    00425     (u_char)'\254', (u_char)'\255', (u_char)'\256', (u_char)'\257',
    00426     (u_char)'\260', (u_char)'\261', (u_char)'\262', (u_char)'\263',
    00427     (u_char)'\264', (u_char)'\265', (u_char)'\266', (u_char)'\267',
    00428     (u_char)'\270', (u_char)'\271', (u_char)'\272', (u_char)'\273',
    00429     (u_char)'\274', (u_char)'\275', (u_char)'\276', (u_char)'\277',
    00430     (u_char)'\300', (u_char)'\341', (u_char)'\342', (u_char)'\343',
    00431     (u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347',
    00432     (u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353',
    00433     (u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357',
    00434     (u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363',
    00435     (u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367',
    00436     (u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\333',
    00437     (u_char)'\334', (u_char)'\335', (u_char)'\336', (u_char)'\337',
    00438     (u_char)'\340', (u_char)'\341', (u_char)'\342', (u_char)'\343',
    00439     (u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347',
    00440     (u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353',
    00441     (u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357',
    00442     (u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363',
    00443     (u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367',
    00444     (u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\373',
    00445     (u_char)'\374', (u_char)'\375', (u_char)'\376', (u_char)'\377',
    00446 };
    00447
    00448 int
    00449 pcap_strcasecmp(const char *s1, const char *s2)
    00450 {
    00451     register const u_char   *cm = charmap,
    00452                 *us1 = (u_char *)s1,
    00453                 *us2 = (u_char *)s2;
    00454
    00455     while (cm[*us1] == cm[*us2++])
    00456         if (*us1++ == '\0')
    00457             return(0);
    00458     return (cm[*us1] - cm[*--us2]);
    00459 }
    00460
    00461 int
    00462 pcap_datalink_name_to_val(const char *name)
    00463 {
    00464     int i;
    00465
    00466     for (i = 0; dlt_choices[i].name != NULL; i++) {
    00467         if (pcap_strcasecmp(dlt_choices[i].name + sizeof("DLT_") - 1,
    00468             name) == 0)
    00469             return (dlt_choices[i].dlt);
    00470     }
    00471     return (-1);
    00472 }
    00473
    00474 const char *
    00475 pcap_datalink_val_to_name(int dlt)
    00476 {
    00477     int i;
    00478
    00479     for (i = 0; dlt_choices[i].name != NULL; i++) {
    00480         if (dlt_choices[i].dlt == dlt)
    00481             return (dlt_choices[i].name + sizeof("DLT_") - 1);
    00482     }
    00483     return (NULL);
    00484 }
    00485
    00486 const char *
    00487 pcap_datalink_val_to_description(int dlt)
    00488 {
    00489     int i;
    00490
    00491     for (i = 0; dlt_choices[i].name != NULL; i++) {
    00492         if (dlt_choices[i].dlt == dlt)
    00493             return (dlt_choices[i].description);
    00494     }
    00495     return (NULL);
    00496 }
    00497
    00498 int
    00499 pcap_snapshot(pcap_t *p)
    00500 {
    00501     return (p->snapshot);
    00502 }
    00503
    00504 int
    00505 pcap_is_swapped(pcap_t *p)
    00506 {
    00507     return (p->sf.swapped);
    00508 }
    00509
    00510 int
    00511 pcap_major_version(pcap_t *p)
    00512 {
    00513     return (p->sf.version_major);
    00514 }
    00515
    00516 int
    00517 pcap_minor_version(pcap_t *p)
    00518 {
    00519     return (p->sf.version_minor);
    00520 }
    00521
    00522 FILE *
    00523 pcap_file(pcap_t *p)
    00524 {
    00525     return (p->sf.rfile);
    00526 }
    00527
    00528 int
    00529 pcap_fileno(pcap_t *p)
    00530 {
    00531 #ifdef HAVE_REMOTE
    00532     if (p->rmt_clientside)
    00533         return(p->rmt_sockdata);
    00534 #endif /* HAVE_REMOTE */
    00535
    00536 #ifndef WIN32
    00537     return (p->fd);
    00538 #else
    00539     if (p->adapter != NULL)
    00540         return ((int)(DWORD)p->adapter->hFile);
    00541     else
    00542         return (-1);
    00543 #endif
    00544 }
    00545
    00546 #ifndef WIN32
    00547 int
    00548 pcap_get_selectable_fd(pcap_t *p)
    00549 {
    00550     return (p->selectable_fd);
    00551 }
    00552 #endif
    00553
    00554 void
    00555 pcap_perror(pcap_t *p, char *prefix)
    00556 {
    00557     fprintf(stderr, "%s: %s\n", prefix, p->errbuf);
    00558 }
    00559
    00560 char *
    00561 pcap_geterr(pcap_t *p)
    00562 {
    00563     return (p->errbuf);
    00564 }
    00565
    00566 int
    00567 pcap_getnonblock(pcap_t *p, char *errbuf)
    00568 {
    00569     return p->getnonblock_op(p, errbuf);
    00570 }
    00571
    00572 /*
    00573  * Get the current non-blocking mode setting, under the assumption that
    00574  * it's just the standard POSIX non-blocking flag.
    00575  *
    00576  * We don't look at "p->nonblock", in case somebody tweaked the FD
    00577  * directly.
    00578  */
    00579 #ifndef WIN32
    00580 int
    00581 pcap_getnonblock_fd(pcap_t *p, char *errbuf)
    00582 {
    00583     int fdflags;
    00584
    00585     fdflags = fcntl(p->fd, F_GETFL, 0);
    00586     if (fdflags == -1) {
    00587         snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_GETFL: %s",
    00588             pcap_strerror(errno));
    00589         return (-1);
    00590     }
    00591     if (fdflags & O_NONBLOCK)
    00592         return (1);
    00593     else
    00594         return (0);
    00595 }
    00596 #endif
    00597
    00598 int
    00599 pcap_setnonblock(pcap_t *p, int nonblock, char *errbuf)
    00600 {
    00601     return p->setnonblock_op(p, nonblock, errbuf);
    00602 }
    00603
    00604 #ifndef WIN32
    00605 /*
    00606  * Set non-blocking mode, under the assumption that it's just the
    00607  * standard POSIX non-blocking flag.  (This can be called by the
    00608  * per-platform non-blocking-mode routine if that routine also
    00609  * needs to do some additional work.)
    00610  */
    00611 int
    00612 pcap_setnonblock_fd(pcap_t *p, int nonblock, char *errbuf)
    00613 {
    00614     int fdflags;
    00615
    00616     fdflags = fcntl(p->fd, F_GETFL, 0);
    00617     if (fdflags == -1) {
    00618         snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_GETFL: %s",
    00619             pcap_strerror(errno));
    00620         return (-1);
    00621     }
    00622     if (nonblock)
    00623         fdflags |= O_NONBLOCK;
    00624     else
    00625         fdflags &= ~O_NONBLOCK;
    00626     if (fcntl(p->fd, F_SETFL, fdflags) == -1) {
    00627         snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_SETFL: %s",
    00628             pcap_strerror(errno));
    00629         return (-1);
    00630     }
    00631     return (0);
    00632 }
    00633 #endif
    00634
    00635 #ifdef WIN32
    00636 /*
    00637  * Generate a string for the last Win32-specific error (i.e. an error generated when
    00638  * calling a Win32 API).
    00639  * For errors occurred during standard C calls, we still use pcap_strerror()
    00640  */
    00641 char *
    00642 pcap_win32strerror(void)
    00643 {
    00644     DWORD error;
    00645     static char errbuf[PCAP_ERRBUF_SIZE+1];
    00646     int errlen;
    00647
    00648     error = GetLastError();
    00649     FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, error, 0, errbuf,
    00650         PCAP_ERRBUF_SIZE, NULL);
    00651
    00652     /*
    00653      * "FormatMessage()" "helpfully" sticks CR/LF at the end of the
    00654      * message.  Get rid of it.
    00655      */
    00656     errlen = strlen(errbuf);
    00657     if (errlen >= 2) {
    00658         errbuf[errlen - 1] = '\0';
    00659         errbuf[errlen - 2] = '\0';
    00660     }
    00661     return (errbuf);
    00662 }
    00663 #endif
    00664
    00665 /*
    00666  * Not all systems have strerror().
    00667  */
    00668 char *
    00669 pcap_strerror(int errnum)
    00670 {
    00671 #ifdef HAVE_STRERROR
    00672     return (strerror(errnum));
    00673 #else
    00674     extern int sys_nerr;
    00675     extern const char *const sys_errlist[];
    00676     static char ebuf[20];
    00677
    00678     if ((unsigned int)errnum < sys_nerr)
    00679         return ((char *)sys_errlist[errnum]);
    00680     (void)snprintf(ebuf, sizeof ebuf, "Unknown error: %d", errnum);
    00681     return(ebuf);
    00682 #endif
    00683 }
    00684
    00685 int
    00686 pcap_setfilter(pcap_t *p, struct bpf_program *fp)
    00687 {
    00688     return p->setfilter_op(p, fp);
    00689 }
    00690
    00691 int
    00692 pcap_stats(pcap_t *p, struct pcap_stat *ps)
    00693 {
    00694     return p->stats_op(p, ps);
    00695 }
    00696
    00697 static int
    00698 pcap_stats_dead(pcap_t *p, struct pcap_stat *ps)
    00699 {
    00700     snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
    00701         "Statistics aren't available from a pcap_open_dead pcap_t");
    00702     return (-1);
    00703 }
    00704
    00705 static void
    00706 pcap_close_dead(pcap_t *p)
    00707 {
    00708     /* Nothing to do. */
    00709 }
    00710
    00711 pcap_t *
    00712 pcap_open_dead(int linktype, int snaplen)
    00713 {
    00714     pcap_t *p;
    00715
    00716     p = malloc(sizeof(*p));
    00717     if (p == NULL)
    00718         return NULL;
    00719     memset (p, 0, sizeof(*p));
    00720     p->snapshot = snaplen;
    00721     p->linktype = linktype;
    00722     p->stats_op = pcap_stats_dead;
    00723     p->close_op = pcap_close_dead;
    00724     return p;
    00725 }
    00726
    00727 void
    00728 pcap_close(pcap_t *p)
    00729 {
    00730     p->close_op(p);
    00731     if (p->dlt_list != NULL)
    00732         free(p->dlt_list);
    00733     pcap_freecode(&p->fcode);
    00734     free(p);
    00735 }
    00736
    00737 /*
    00738  * We make the version string static, and return a pointer to it, rather
    00739  * than exporting the version string directly.  On at least some UNIXes,
    00740  * if you import data from a shared library into an program, the data is
    00741  * bound into the program binary, so if the string in the version of the
    00742  * library with which the program was linked isn't the same as the
    00743  * string in the version of the library with which the program is being
    00744  * run, various undesirable things may happen (warnings, the string
    00745  * being the one from the version of the library with which the program
    00746  * was linked, or even weirder things, such as the string being the one
    00747  * from the library but being truncated).
    00748  */
    00749 #ifdef WIN32
    00750 /*
    00751  * XXX - it'd be nice if we could somehow generate the WinPcap and libpcap
    00752  * version numbers when building WinPcap.  (It'd be nice to do so for
    00753  * the packet.dll version number as well.)
    00754  */
    00755 static const char wpcap_version_string[] = "3.0";
    00756 static const char pcap_version_string_fmt[] =
    00757     "WinPcap version %s, based on libpcap version 0.8";
    00758 static const char pcap_version_string_packet_dll_fmt[] =
    00759     "WinPcap version %s (packet.dll version %s), based on libpcap version 0.8";
    00760 static char *pcap_version_string;
    00761
    00762 const char *
    00763 pcap_lib_version(void)
    00764 {
    00765     char *packet_version_string;
    00766     size_t pcap_version_string_len;
    00767
    00768     if (pcap_version_string == NULL) {
    00769         /*
    00770          * Generate the version string.
    00771          */
    00772         packet_version_string = PacketGetVersion();
    00773         if (strcmp(wpcap_version_string, packet_version_string) == 0) {
    00774             /*
    00775              * WinPcap version string and packet.dll version
    00776              * string are the same; just report the WinPcap
    00777              * version.
    00778              */
    00779             pcap_version_string_len =
    00780                 (sizeof pcap_version_string_fmt - 2) +
    00781                 strlen(wpcap_version_string);
    00782             pcap_version_string = malloc(pcap_version_string_len);
    00783             sprintf(pcap_version_string, pcap_version_string_fmt,
    00784                 wpcap_version_string);
    00785         } else {
    00786             /*
    00787              * WinPcap version string and packet.dll version
    00788              * string are different; that shouldn't be the
    00789              * case (the two libraries should come from the
    00790              * same version of WinPcap), so we report both
    00791              * versions.
    00792              */
    00793             pcap_version_string_len =
    00794                 (sizeof pcap_version_string_packet_dll_fmt - 4) +
    00795                 strlen(wpcap_version_string) +
    00796                 strlen(packet_version_string);
    00797             pcap_version_string = malloc(pcap_version_string_len);
    00798             sprintf(pcap_version_string,
    00799                 pcap_version_string_packet_dll_fmt,
    00800                 wpcap_version_string, packet_version_string);
    00801         }
    00802     }
    00803     return (pcap_version_string);
    00804 }
    00805 #else
    00806 #include "version.h"
    00807
    00808 const char *
    00809 pcap_lib_version(void)
    00810 {
    00811     return (pcap_version_string);
    00812 }
    00813 #endif

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