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 #ifdef HAVE_REMOTE 00097 /* Checks the capture type */ 00098 if (p->rmt_clientside) 00099 { 00100 /* We are on an remote capture */ 00101 if (!p->rmt_capstarted) 00102 { 00103 // if the capture has not started yet, please start it 00104 if (pcap_startcapture_remote(p) ) 00105 return -1; 00106 } 00107 } 00108 #endif /* HAVE_REMOTE */ 00109 00110 for (;;) { 00111 if (p->sf.rfile != NULL) { 00112 /* 00113 * 0 means EOF, so don't loop if we get 0. 00114 */ 00115 n = pcap_offline_read(p, cnt, callback, user); 00116 } else { 00117 /* 00118 * XXX keep reading until we get something 00119 * (or an error occurs) 00120 */ 00121 do { 00122 n = p->read_op(p, cnt, callback, user); 00123 } while (n == 0); 00124 } 00125 if (n <= 0) 00126 return (n); 00127 if (cnt > 0) { 00128 cnt -= n; 00129 if (cnt <= 0) 00130 return (0); 00131 } 00132 } 00133 } 00134 00135 struct singleton { 00136 struct pcap_pkthdr *hdr; 00137 const u_char *pkt; 00138 }; 00139 00140 00141 static void 00142 pcap_oneshot(u_char *userData, const struct pcap_pkthdr *h, const u_char *pkt) 00143 { 00144 struct singleton *sp = (struct singleton *)userData; 00145 *sp->hdr = *h; 00146 sp->pkt = pkt; 00147 } 00148 00149 const u_char * 00150 pcap_next(pcap_t *p, struct pcap_pkthdr *h) 00151 { 00152 struct singleton s; 00153 00154 s.hdr = h; 00155 if (pcap_dispatch(p, 1, pcap_oneshot, (u_char*)&s) <= 0) 00156 return (0); 00157 return (s.pkt); 00158 } 00159 00160 struct pkt_for_fakecallback { 00161 struct pcap_pkthdr *hdr; 00162 const u_char **pkt; 00163 }; 00164 00165 static void 00166 pcap_fakecallback(u_char *userData, const struct pcap_pkthdr *h, 00167 const u_char *pkt) 00168 { 00169 struct pkt_for_fakecallback *sp = (struct pkt_for_fakecallback *)userData; 00170 00171 *sp->hdr = *h; 00172 *sp->pkt = pkt; 00173 } 00174 00175 int 00176 pcap_next_ex(pcap_t *p, struct pcap_pkthdr **pkt_header, 00177 const u_char **pkt_data) 00178 { 00179 struct pkt_for_fakecallback s; 00180 00181 s.hdr = &p->pcap_header; 00182 s.pkt = pkt_data; 00183 00184 /* Saves a pointer to the packet headers */ 00185 *pkt_header= &p->pcap_header; 00186 00187 #ifdef HAVE_REMOTE 00188 /* Checks the capture type */ 00189 if (p->rmt_clientside) 00190 { 00191 /* We are on an remote capture */ 00192 if (!p->rmt_capstarted) 00193 { 00194 // if the capture has not started yet, please start it 00195 if (pcap_startcapture_remote(p) ) 00196 return -1; 00197 } 00198 00199 return pcap_read_nocb_remote(p, pkt_header, (u_char **) pkt_data); 00200 } 00201 #endif /* HAVE_REMOTE */ 00202 00203 if (p->sf.rfile != NULL) { 00204 int status; 00205 00206 /* We are on an offline capture */ 00207 status = pcap_offline_read(p, 1, pcap_fakecallback, 00208 (u_char *)&s); 00209 00210 /* 00211 * Return codes for pcap_offline_read() are: 00212 * - 0: EOF 00213 * - -1: error 00214 * - >1: OK 00215 * The first one ('0') conflicts with the return code of 00216 * 0 from pcap_read() meaning "no packets arrived before 00217 * the timeout expired", so we map it to -2 so you can 00218 * distinguish between an EOF from a savefile and a 00219 * "no packets arrived before the timeout expired, try 00220 * again" from a live capture. 00221 */ 00222 if (status == 0) 00223 return (-2); 00224 else 00225 return (status); 00226 } 00227 00228 /* 00229 * Return codes for pcap_read() are: 00230 * - 0: timeout 00231 * - -1: error 00232 * - -2: loop was broken out of with pcap_breakloop() 00233 * - >1: OK 00234 * The first one ('0') conflicts with the return code of 0 from 00235 * pcap_offline_read() meaning "end of file". 00236 */ 00237 return (p->read_op(p, 1, pcap_fakecallback, (u_char *)&s)); 00238 } 00239 00240 /* 00241 * Force the loop in "pcap_read()" or "pcap_read_offline()" to terminate. 00242 */ 00243 void 00244 pcap_breakloop(pcap_t *p) 00245 { 00246 p->break_loop = 1; 00247 } 00248 00249 int 00250 pcap_datalink(pcap_t *p) 00251 { 00252 return (p->linktype); 00253 } 00254 00255 int 00256 pcap_list_datalinks(pcap_t *p, int **dlt_buffer) 00257 { 00258 if (p->dlt_count == 0) { 00259 /* 00260 * We couldn't fetch the list of DLTs, which means 00261 * this platform doesn't support changing the 00262 * DLT for an interface. Return a list of DLTs 00263 * containing only the DLT this device supports. 00264 */ 00265 *dlt_buffer = (int*)malloc(sizeof(**dlt_buffer)); 00266 if (*dlt_buffer == NULL) { 00267 (void)snprintf(p->errbuf, sizeof(p->errbuf), 00268 "malloc: %s", pcap_strerror(errno)); 00269 return (-1); 00270 } 00271 **dlt_buffer = p->linktype; 00272 return (1); 00273 } else { 00274 *dlt_buffer = (int*)malloc(sizeof(**dlt_buffer) * p->dlt_count); 00275 if (*dlt_buffer == NULL) { 00276 (void)snprintf(p->errbuf, sizeof(p->errbuf), 00277 "malloc: %s", pcap_strerror(errno)); 00278 return (-1); 00279 } 00280 (void)memcpy(*dlt_buffer, p->dlt_list, 00281 sizeof(**dlt_buffer) * p->dlt_count); 00282 return (p->dlt_count); 00283 } 00284 } 00285 00286 int 00287 pcap_set_datalink(pcap_t *p, int dlt) 00288 { 00289 int i; 00290 const char *dlt_name; 00291 00292 if (p->dlt_count == 0 || p->set_datalink_op == NULL) { 00293 /* 00294 * We couldn't fetch the list of DLTs, or we don't 00295 * have a "set datalink" operation, which means 00296 * this platform doesn't support changing the 00297 * DLT for an interface. Check whether the new 00298 * DLT is the one this interface supports. 00299 */ 00300 if (p->linktype != dlt) 00301 goto unsupported; 00302 00303 /* 00304 * It is, so there's nothing we need to do here. 00305 */ 00306 return (0); 00307 } 00308 for (i = 0; i < p->dlt_count; i++) 00309 if (p->dlt_list[i] == dlt) 00310 break; 00311 if (i >= p->dlt_count) 00312 goto unsupported; 00313 if (p->dlt_count == 2 && p->dlt_list[0] == DLT_EN10MB && 00314 dlt == DLT_DOCSIS) { 00315 /* 00316 * This is presumably an Ethernet device, as the first 00317 * link-layer type it offers is DLT_EN10MB, and the only 00318 * other type it offers is DLT_DOCSIS. That means that 00319 * we can't tell the driver to supply DOCSIS link-layer 00320 * headers - we're just pretending that's what we're 00321 * getting, as, presumably, we're capturing on a dedicated 00322 * link to a Cisco Cable Modem Termination System, and 00323 * it's putting raw DOCSIS frames on the wire inside low-level 00324 * Ethernet framing. 00325 */ 00326 p->linktype = dlt; 00327 return (0); 00328 } 00329 if (p->set_datalink_op(p, dlt) == -1) 00330 return (-1); 00331 p->linktype = dlt; 00332 return (0); 00333 00334 unsupported: 00335 dlt_name = pcap_datalink_val_to_name(dlt); 00336 if (dlt_name != NULL) { 00337 (void) snprintf(p->errbuf, sizeof(p->errbuf), 00338 "%s is not one of the DLTs supported by this device", 00339 dlt_name); 00340 } else { 00341 (void) snprintf(p->errbuf, sizeof(p->errbuf), 00342 "DLT %d is not one of the DLTs supported by this device", 00343 dlt); 00344 } 00345 return (-1); 00346 } 00347 00348 struct dlt_choice { 00349 const char *name; 00350 const char *description; 00351 int dlt; 00352 }; 00353 00354 #define DLT_CHOICE(code, description) { #code, description, code } 00355 #define DLT_CHOICE_SENTINEL { NULL, NULL, 0 } 00356 00357 static struct dlt_choice dlt_choices[] = { 00358 DLT_CHOICE(DLT_NULL, "BSD loopback"), 00359 DLT_CHOICE(DLT_EN10MB, "Ethernet"), 00360 DLT_CHOICE(DLT_IEEE802, "Token ring"), 00361 DLT_CHOICE(DLT_ARCNET, "ARCNET"), 00362 DLT_CHOICE(DLT_SLIP, "SLIP"), 00363 DLT_CHOICE(DLT_PPP, "PPP"), 00364 DLT_CHOICE(DLT_FDDI, "FDDI"), 00365 DLT_CHOICE(DLT_ATM_RFC1483, "RFC 1483 IP-over-ATM"), 00366 DLT_CHOICE(DLT_RAW, "Raw IP"), 00367 DLT_CHOICE(DLT_SLIP_BSDOS, "BSD/OS SLIP"), 00368 DLT_CHOICE(DLT_PPP_BSDOS, "BSD/OS PPP"), 00369 DLT_CHOICE(DLT_ATM_CLIP, "Linux Classical IP-over-ATM"), 00370 DLT_CHOICE(DLT_PPP_SERIAL, "PPP over serial"), 00371 DLT_CHOICE(DLT_PPP_ETHER, "PPPoE"), 00372 DLT_CHOICE(DLT_C_HDLC, "Cisco HDLC"), 00373 DLT_CHOICE(DLT_IEEE802_11, "802.11"), 00374 DLT_CHOICE(DLT_FRELAY, "Frame Relay"), 00375 DLT_CHOICE(DLT_LOOP, "OpenBSD loopback"), 00376 DLT_CHOICE(DLT_ENC, "OpenBSD encapsulated IP"), 00377 DLT_CHOICE(DLT_LINUX_SLL, "Linux cooked"), 00378 DLT_CHOICE(DLT_LTALK, "Localtalk"), 00379 DLT_CHOICE(DLT_PFLOG, "OpenBSD pflog file"), 00380 DLT_CHOICE(DLT_PRISM_HEADER, "802.11 plus Prism header"), 00381 DLT_CHOICE(DLT_IP_OVER_FC, "RFC 2625 IP-over-Fibre Channel"), 00382 DLT_CHOICE(DLT_SUNATM, "Sun raw ATM"), 00383 DLT_CHOICE(DLT_IEEE802_11_RADIO, "802.11 plus radio information header"), 00384 DLT_CHOICE(DLT_ARCNET_LINUX, "Linux ARCNET"), 00385 DLT_CHOICE(DLT_DOCSIS, "DOCSIS"), 00386 DLT_CHOICE(DLT_LINUX_IRDA, "Linux IrDA"), 00387 DLT_CHOICE_SENTINEL 00388 }; 00389 00390 /* 00391 * This array is designed for mapping upper and lower case letter 00392 * together for a case independent comparison. The mappings are 00393 * based upon ascii character sequences. 00394 */ 00395 static const u_char charmap[] = { 00396 (u_char)'\000', (u_char)'\001', (u_char)'\002', (u_char)'\003', 00397 (u_char)'\004', (u_char)'\005', (u_char)'\006', (u_char)'\007', 00398 (u_char)'\010', (u_char)'\011', (u_char)'\012', (u_char)'\013', 00399 (u_char)'\014', (u_char)'\015', (u_char)'\016', (u_char)'\017', 00400 (u_char)'\020', (u_char)'\021', (u_char)'\022', (u_char)'\023', 00401 (u_char)'\024', (u_char)'\025', (u_char)'\026', (u_char)'\027', 00402 (u_char)'\030', (u_char)'\031', (u_char)'\032', (u_char)'\033', 00403 (u_char)'\034', (u_char)'\035', (u_char)'\036', (u_char)'\037', 00404 (u_char)'\040', (u_char)'\041', (u_char)'\042', (u_char)'\043', 00405 (u_char)'\044', (u_char)'\045', (u_char)'\046', (u_char)'\047', 00406 (u_char)'\050', (u_char)'\051', (u_char)'\052', (u_char)'\053', 00407 (u_char)'\054', (u_char)'\055', (u_char)'\056', (u_char)'\057', 00408 (u_char)'\060', (u_char)'\061', (u_char)'\062', (u_char)'\063', 00409 (u_char)'\064', (u_char)'\065', (u_char)'\066', (u_char)'\067', 00410 (u_char)'\070', (u_char)'\071', (u_char)'\072', (u_char)'\073', 00411 (u_char)'\074', (u_char)'\075', (u_char)'\076', (u_char)'\077', 00412 (u_char)'\100', (u_char)'\141', (u_char)'\142', (u_char)'\143', 00413 (u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147', 00414 (u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153', 00415 (u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157', 00416 (u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163', 00417 (u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167', 00418 (u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\133', 00419 (u_char)'\134', (u_char)'\135', (u_char)'\136', (u_char)'\137', 00420 (u_char)'\140', (u_char)'\141', (u_char)'\142', (u_char)'\143', 00421 (u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147', 00422 (u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153', 00423 (u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157', 00424 (u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163', 00425 (u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167', 00426 (u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\173', 00427 (u_char)'\174', (u_char)'\175', (u_char)'\176', (u_char)'\177', 00428 (u_char)'\200', (u_char)'\201', (u_char)'\202', (u_char)'\203', 00429 (u_char)'\204', (u_char)'\205', (u_char)'\206', (u_char)'\207', 00430 (u_char)'\210', (u_char)'\211', (u_char)'\212', (u_char)'\213', 00431 (u_char)'\214', (u_char)'\215', (u_char)'\216', (u_char)'\217', 00432 (u_char)'\220', (u_char)'\221', (u_char)'\222', (u_char)'\223', 00433 (u_char)'\224', (u_char)'\225', (u_char)'\226', (u_char)'\227', 00434 (u_char)'\230', (u_char)'\231', (u_char)'\232', (u_char)'\233', 00435 (u_char)'\234', (u_char)'\235', (u_char)'\236', (u_char)'\237', 00436 (u_char)'\240', (u_char)'\241', (u_char)'\242', (u_char)'\243', 00437 (u_char)'\244', (u_char)'\245', (u_char)'\246', (u_char)'\247', 00438 (u_char)'\250', (u_char)'\251', (u_char)'\252', (u_char)'\253', 00439 (u_char)'\254', (u_char)'\255', (u_char)'\256', (u_char)'\257', 00440 (u_char)'\260', (u_char)'\261', (u_char)'\262', (u_char)'\263', 00441 (u_char)'\264', (u_char)'\265', (u_char)'\266', (u_char)'\267', 00442 (u_char)'\270', (u_char)'\271', (u_char)'\272', (u_char)'\273', 00443 (u_char)'\274', (u_char)'\275', (u_char)'\276', (u_char)'\277', 00444 (u_char)'\300', (u_char)'\341', (u_char)'\342', (u_char)'\343', 00445 (u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347', 00446 (u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353', 00447 (u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357', 00448 (u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363', 00449 (u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367', 00450 (u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\333', 00451 (u_char)'\334', (u_char)'\335', (u_char)'\336', (u_char)'\337', 00452 (u_char)'\340', (u_char)'\341', (u_char)'\342', (u_char)'\343', 00453 (u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347', 00454 (u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353', 00455 (u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357', 00456 (u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363', 00457 (u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367', 00458 (u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\373', 00459 (u_char)'\374', (u_char)'\375', (u_char)'\376', (u_char)'\377', 00460 }; 00461 00462 int 00463 pcap_strcasecmp(const char *s1, const char *s2) 00464 { 00465 register const u_char *cm = charmap, 00466 *us1 = (u_char *)s1, 00467 *us2 = (u_char *)s2; 00468 00469 while (cm[*us1] == cm[*us2++]) 00470 if (*us1++ == '\0') 00471 return(0); 00472 return (cm[*us1] - cm[*--us2]); 00473 } 00474 00475 int 00476 pcap_datalink_name_to_val(const char *name) 00477 { 00478 int i; 00479 00480 for (i = 0; dlt_choices[i].name != NULL; i++) { 00481 if (pcap_strcasecmp(dlt_choices[i].name + sizeof("DLT_") - 1, 00482 name) == 0) 00483 return (dlt_choices[i].dlt); 00484 } 00485 return (-1); 00486 } 00487 00488 const char * 00489 pcap_datalink_val_to_name(int dlt) 00490 { 00491 int i; 00492 00493 for (i = 0; dlt_choices[i].name != NULL; i++) { 00494 if (dlt_choices[i].dlt == dlt) 00495 return (dlt_choices[i].name + sizeof("DLT_") - 1); 00496 } 00497 return (NULL); 00498 } 00499 00500 const char * 00501 pcap_datalink_val_to_description(int dlt) 00502 { 00503 int i; 00504 00505 for (i = 0; dlt_choices[i].name != NULL; i++) { 00506 if (dlt_choices[i].dlt == dlt) 00507 return (dlt_choices[i].description); 00508 } 00509 return (NULL); 00510 } 00511 00512 int 00513 pcap_snapshot(pcap_t *p) 00514 { 00515 return (p->snapshot); 00516 } 00517 00518 int 00519 pcap_is_swapped(pcap_t *p) 00520 { 00521 return (p->sf.swapped); 00522 } 00523 00524 int 00525 pcap_major_version(pcap_t *p) 00526 { 00527 return (p->sf.version_major); 00528 } 00529 00530 int 00531 pcap_minor_version(pcap_t *p) 00532 { 00533 return (p->sf.version_minor); 00534 } 00535 00536 FILE * 00537 pcap_file(pcap_t *p) 00538 { 00539 return (p->sf.rfile); 00540 } 00541 00542 int 00543 pcap_fileno(pcap_t *p) 00544 { 00545 #ifdef HAVE_REMOTE 00546 if (p->rmt_clientside) 00547 return(p->rmt_sockdata); 00548 #endif /* HAVE_REMOTE */ 00549 00550 #ifndef WIN32 00551 return (p->fd); 00552 #else 00553 if (p->adapter != NULL) 00554 return ((int)(DWORD)p->adapter->hFile); 00555 else 00556 return (-1); 00557 #endif 00558 } 00559 00560 #ifndef WIN32 00561 int 00562 pcap_get_selectable_fd(pcap_t *p) 00563 { 00564 return (p->selectable_fd); 00565 } 00566 #endif 00567 00568 void 00569 pcap_perror(pcap_t *p, char *prefix) 00570 { 00571 fprintf(stderr, "%s: %s\n", prefix, p->errbuf); 00572 } 00573 00574 char * 00575 pcap_geterr(pcap_t *p) 00576 { 00577 return (p->errbuf); 00578 } 00579 00580 int 00581 pcap_getnonblock(pcap_t *p, char *errbuf) 00582 { 00583 return p->getnonblock_op(p, errbuf); 00584 } 00585 00586 /* 00587 * Get the current non-blocking mode setting, under the assumption that 00588 * it's just the standard POSIX non-blocking flag. 00589 * 00590 * We don't look at "p->nonblock", in case somebody tweaked the FD 00591 * directly. 00592 */ 00593 #ifndef WIN32 00594 int 00595 pcap_getnonblock_fd(pcap_t *p, char *errbuf) 00596 { 00597 int fdflags; 00598 00599 fdflags = fcntl(p->fd, F_GETFL, 0); 00600 if (fdflags == -1) { 00601 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_GETFL: %s", 00602 pcap_strerror(errno)); 00603 return (-1); 00604 } 00605 if (fdflags & O_NONBLOCK) 00606 return (1); 00607 else 00608 return (0); 00609 } 00610 #endif 00611 00612 int 00613 pcap_setnonblock(pcap_t *p, int nonblock, char *errbuf) 00614 { 00615 return p->setnonblock_op(p, nonblock, errbuf); 00616 } 00617 00618 #ifndef WIN32 00619 /* 00620 * Set non-blocking mode, under the assumption that it's just the 00621 * standard POSIX non-blocking flag. (This can be called by the 00622 * per-platform non-blocking-mode routine if that routine also 00623 * needs to do some additional work.) 00624 */ 00625 int 00626 pcap_setnonblock_fd(pcap_t *p, int nonblock, char *errbuf) 00627 { 00628 int fdflags; 00629 00630 fdflags = fcntl(p->fd, F_GETFL, 0); 00631 if (fdflags == -1) { 00632 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_GETFL: %s", 00633 pcap_strerror(errno)); 00634 return (-1); 00635 } 00636 if (nonblock) 00637 fdflags |= O_NONBLOCK; 00638 else 00639 fdflags &= ~O_NONBLOCK; 00640 if (fcntl(p->fd, F_SETFL, fdflags) == -1) { 00641 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_SETFL: %s", 00642 pcap_strerror(errno)); 00643 return (-1); 00644 } 00645 return (0); 00646 } 00647 #endif 00648 00649 #ifdef WIN32 00650 /* 00651 * Generate a string for the last Win32-specific error (i.e. an error generated when 00652 * calling a Win32 API). 00653 * For errors occurred during standard C calls, we still use pcap_strerror() 00654 */ 00655 char * 00656 pcap_win32strerror(void) 00657 { 00658 DWORD error; 00659 static char errbuf[PCAP_ERRBUF_SIZE+1]; 00660 int errlen; 00661 00662 error = GetLastError(); 00663 FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, error, 0, errbuf, 00664 PCAP_ERRBUF_SIZE, NULL); 00665 00666 /* 00667 * "FormatMessage()" "helpfully" sticks CR/LF at the end of the 00668 * message. Get rid of it. 00669 */ 00670 errlen = strlen(errbuf); 00671 if (errlen >= 2) { 00672 errbuf[errlen - 1] = '\0'; 00673 errbuf[errlen - 2] = '\0'; 00674 } 00675 return (errbuf); 00676 } 00677 #endif 00678 00679 /* 00680 * Not all systems have strerror(). 00681 */ 00682 char * 00683 pcap_strerror(int errnum) 00684 { 00685 #ifdef HAVE_STRERROR 00686 return (strerror(errnum)); 00687 #else 00688 extern int sys_nerr; 00689 extern const char *const sys_errlist[]; 00690 static char ebuf[20]; 00691 00692 if ((unsigned int)errnum < sys_nerr) 00693 return ((char *)sys_errlist[errnum]); 00694 (void)snprintf(ebuf, sizeof ebuf, "Unknown error: %d", errnum); 00695 return(ebuf); 00696 #endif 00697 } 00698 00699 int 00700 pcap_setfilter(pcap_t *p, struct bpf_program *fp) 00701 { 00702 return p->setfilter_op(p, fp); 00703 } 00704 00705 int 00706 pcap_stats(pcap_t *p, struct pcap_stat *ps) 00707 { 00708 return p->stats_op(p, ps); 00709 } 00710 00711 static int 00712 pcap_stats_dead(pcap_t *p, struct pcap_stat *ps) 00713 { 00714 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 00715 "Statistics aren't available from a pcap_open_dead pcap_t"); 00716 return (-1); 00717 } 00718 00719 static void 00720 pcap_close_dead(pcap_t *p) 00721 { 00722 /* Nothing to do. */ 00723 } 00724 00725 pcap_t * 00726 pcap_open_dead(int linktype, int snaplen) 00727 { 00728 pcap_t *p; 00729 00730 p = malloc(sizeof(*p)); 00731 if (p == NULL) 00732 return NULL; 00733 memset (p, 0, sizeof(*p)); 00734 p->snapshot = snaplen; 00735 p->linktype = linktype; 00736 p->stats_op = pcap_stats_dead; 00737 p->close_op = pcap_close_dead; 00738 return p; 00739 } 00740 00741 void 00742 pcap_close(pcap_t *p) 00743 { 00744 p->close_op(p); 00745 if (p->dlt_list != NULL) 00746 free(p->dlt_list); 00747 pcap_freecode(&p->fcode); 00748 free(p); 00749 } 00750 00751 /* 00752 * We make the version string static, and return a pointer to it, rather 00753 * than exporting the version string directly. On at least some UNIXes, 00754 * if you import data from a shared library into an program, the data is 00755 * bound into the program binary, so if the string in the version of the 00756 * library with which the program was linked isn't the same as the 00757 * string in the version of the library with which the program is being 00758 * run, various undesirable things may happen (warnings, the string 00759 * being the one from the version of the library with which the program 00760 * was linked, or even weirder things, such as the string being the one 00761 * from the library but being truncated). 00762 */ 00763 #ifdef WIN32 00764 /* 00765 * XXX - it'd be nice if we could somehow generate the WinPcap and libpcap 00766 * version numbers when building WinPcap. (It'd be nice to do so for 00767 * the packet.dll version number as well.) 00768 */ 00769 static const char wpcap_version_string[] = "3.1 beta2"; 00770 static const char pcap_version_string_fmt[] = 00771 "WinPcap version %s, based on libpcap version 0.8.1"; 00772 static const char pcap_version_string_packet_dll_fmt[] = 00773 "WinPcap version %s (packet.dll version %s), based on libpcap version 0.8.1"; 00774 static char *pcap_version_string; 00775 00776 const char * 00777 pcap_lib_version(void) 00778 { 00779 char *packet_version_string; 00780 size_t pcap_version_string_len; 00781 00782 if (pcap_version_string == NULL) { 00783 /* 00784 * Generate the version string. 00785 */ 00786 packet_version_string = PacketGetVersion(); 00787 if (strcmp(wpcap_version_string, packet_version_string) == 0) { 00788 /* 00789 * WinPcap version string and packet.dll version 00790 * string are the same; just report the WinPcap 00791 * version. 00792 */ 00793 pcap_version_string_len = 00794 (sizeof pcap_version_string_fmt - 2) + 00795 strlen(wpcap_version_string); 00796 pcap_version_string = malloc(pcap_version_string_len); 00797 sprintf(pcap_version_string, pcap_version_string_fmt, 00798 wpcap_version_string); 00799 } else { 00800 /* 00801 * WinPcap version string and packet.dll version 00802 * string are different; that shouldn't be the 00803 * case (the two libraries should come from the 00804 * same version of WinPcap), so we report both 00805 * versions. 00806 */ 00807 pcap_version_string_len = 00808 (sizeof pcap_version_string_packet_dll_fmt - 4) + 00809 strlen(wpcap_version_string) + 00810 strlen(packet_version_string); 00811 pcap_version_string = malloc(pcap_version_string_len); 00812 sprintf(pcap_version_string, 00813 pcap_version_string_packet_dll_fmt, 00814 wpcap_version_string, packet_version_string); 00815 } 00816 } 00817 return (pcap_version_string); 00818 } 00819 #else 00820 #include "version.h" 00821 00822 const char * 00823 pcap_lib_version(void) 00824 { 00825 return (pcap_version_string); 00826 } 00827 #endif
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