1 /* 2 * Copyright (c) 1993, 1994, 1995, 1996, 1997, 1998 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the Computer Systems 16 * Engineering Group at Lawrence Berkeley Laboratory. 17 * 4. Neither the name of the University nor of the Laboratory may be used 18 * to endorse or promote products derived from this software without 19 * specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 static const char rcsid[] = 36 "@(#) $Header: /tcpdump/master/libpcap/pcap.c,v 1.29.1.1 1999/10/07 23:46:40 mcr Exp $ (LBL)"; 37 #endif 38 39 #include <sys/types.h> 40 41 #include <stdio.h> 42 #include <stdlib.h> 43 #include <string.h> 44 #include <unistd.h> 45 46 #include "gnuc.h" 47 #ifdef HAVE_OS_PROTO_H 48 #include "os-proto.h" 49 #endif 50 51 #include "pcap-int.h" 52 53 int 54 pcap_dispatch(pcap_t *p, int cnt, pcap_handler callback, u_char *user) 55 { 56 57 if (p->sf.rfile != NULL) 58 return (pcap_offline_read(p, cnt, callback, user)); 59 return (pcap_read(p, cnt, callback, user)); 60 } 61 62 int 63 pcap_loop(pcap_t *p, int cnt, pcap_handler callback, u_char *user) 64 { 65 register int n; 66 67 for (;;) { 68 if (p->sf.rfile != NULL) 69 n = pcap_offline_read(p, cnt, callback, user); 70 else { 71 /* 72 * XXX keep reading until we get something 73 * (or an error occurs) 74 */ 75 do { 76 n = pcap_read(p, cnt, callback, user); 77 } while (n == 0); 78 } 79 if (n <= 0) 80 return (n); 81 if (cnt > 0) { 82 cnt -= n; 83 if (cnt <= 0) 84 return (0); 85 } 86 } 87 } 88 89 struct singleton { 90 struct pcap_pkthdr *hdr; 91 const u_char *pkt; 92 }; 93 94 95 static void 96 pcap_oneshot(u_char *userData, const struct pcap_pkthdr *h, const u_char *pkt) 97 { 98 struct singleton *sp = (struct singleton *)userData; 99 *sp->hdr = *h; 100 sp->pkt = pkt; 101 } 102 103 const u_char * 104 pcap_next(pcap_t *p, struct pcap_pkthdr *h) 105 { 106 struct singleton s; 107 108 s.hdr = h; 109 if (pcap_dispatch(p, 1, pcap_oneshot, (u_char*)&s) <= 0) 110 return (0); 111 return (s.pkt); 112 } 113 114 int 115 pcap_datalink(pcap_t *p) 116 { 117 return (p->linktype); 118 } 119 120 int 121 pcap_snapshot(pcap_t *p) 122 { 123 return (p->snapshot); 124 } 125 126 int 127 pcap_is_swapped(pcap_t *p) 128 { 129 return (p->sf.swapped); 130 } 131 132 int 133 pcap_major_version(pcap_t *p) 134 { 135 return (p->sf.version_major); 136 } 137 138 int 139 pcap_minor_version(pcap_t *p) 140 { 141 return (p->sf.version_minor); 142 } 143 144 FILE * 145 pcap_file(pcap_t *p) 146 { 147 return (p->sf.rfile); 148 } 149 150 int 151 pcap_fileno(pcap_t *p) 152 { 153 return (p->fd); 154 } 155 156 void 157 pcap_perror(pcap_t *p, char *prefix) 158 { 159 fprintf(stderr, "%s: %s\n", prefix, p->errbuf); 160 } 161 162 char * 163 pcap_geterr(pcap_t *p) 164 { 165 return (p->errbuf); 166 } 167 168 /* 169 * Not all systems have strerror(). 170 */ 171 char * 172 pcap_strerror(int errnum) 173 { 174 #ifdef HAVE_STRERROR 175 return (strerror(errnum)); 176 #else 177 extern int sys_nerr; 178 extern const char *const sys_errlist[]; 179 static char ebuf[20]; 180 181 if ((unsigned int)errnum < sys_nerr) 182 return ((char *)sys_errlist[errnum]); 183 (void)sprintf(ebuf, "Unknown error: %d", errnum); 184 return(ebuf); 185 #endif 186 } 187 188 void 189 pcap_close(pcap_t *p) 190 { 191 /*XXX*/ 192 if (p->fd >= 0) 193 close(p->fd); 194 if (p->sf.rfile != NULL) { 195 (void)fclose(p->sf.rfile); 196 if (p->sf.base != NULL) 197 free(p->sf.base); 198 } else if (p->buffer != NULL) 199 free(p->buffer); 200 #ifdef linux 201 if (p->md.device != NULL) 202 free(p->md.device); 203 #endif 204 205 free(p); 206 } 207