| /* |
| * Copyright (c) 1993, 1994, 1995, 1996, 1997, 1998 |
| * The Regents of the University of California. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. All advertising materials mentioning features or use of this software |
| * must display the following acknowledgement: |
| * This product includes software developed by the Computer Systems |
| * Engineering Group at Lawrence Berkeley Laboratory. |
| * 4. Neither the name of the University nor of the Laboratory may be used |
| * to endorse or promote products derived from this software without |
| * specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| #ifndef lint |
| static const char rcsid[] = |
| "@(#) $Header: /tcpdump/master/libpcap/pcap.c,v 1.41 2002-08-02 03:44:21 guy Exp $ (LBL)"; |
| #endif |
| |
| #ifdef HAVE_CONFIG_H |
| #include "config.h" |
| #endif |
| |
| #ifdef WIN32 |
| #include <pcap-stdinc.h> |
| #else /* WIN32 */ |
| #include <sys/types.h> |
| #endif /* WIN32 */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #ifndef WIN32 |
| #include <unistd.h> |
| #endif |
| #include <fcntl.h> |
| #include <errno.h> |
| |
| #ifdef HAVE_OS_PROTO_H |
| #include "os-proto.h" |
| #endif |
| |
| #include "pcap-int.h" |
| |
| int |
| pcap_dispatch(pcap_t *p, int cnt, pcap_handler callback, u_char *user) |
| { |
| |
| if (p->sf.rfile != NULL) |
| return (pcap_offline_read(p, cnt, callback, user)); |
| return (pcap_read(p, cnt, callback, user)); |
| } |
| |
| int |
| pcap_loop(pcap_t *p, int cnt, pcap_handler callback, u_char *user) |
| { |
| register int n; |
| |
| for (;;) { |
| if (p->sf.rfile != NULL) |
| n = pcap_offline_read(p, cnt, callback, user); |
| else { |
| /* |
| * XXX keep reading until we get something |
| * (or an error occurs) |
| */ |
| do { |
| n = pcap_read(p, cnt, callback, user); |
| } while (n == 0); |
| } |
| if (n <= 0) |
| return (n); |
| if (cnt > 0) { |
| cnt -= n; |
| if (cnt <= 0) |
| return (0); |
| } |
| } |
| } |
| |
| struct singleton { |
| struct pcap_pkthdr *hdr; |
| const u_char *pkt; |
| }; |
| |
| |
| static void |
| pcap_oneshot(u_char *userData, const struct pcap_pkthdr *h, const u_char *pkt) |
| { |
| struct singleton *sp = (struct singleton *)userData; |
| *sp->hdr = *h; |
| sp->pkt = pkt; |
| } |
| |
| const u_char * |
| pcap_next(pcap_t *p, struct pcap_pkthdr *h) |
| { |
| struct singleton s; |
| |
| s.hdr = h; |
| if (pcap_dispatch(p, 1, pcap_oneshot, (u_char*)&s) <= 0) |
| return (0); |
| return (s.pkt); |
| } |
| |
| int |
| pcap_datalink(pcap_t *p) |
| { |
| return (p->linktype); |
| } |
| |
| int |
| pcap_snapshot(pcap_t *p) |
| { |
| return (p->snapshot); |
| } |
| |
| int |
| pcap_is_swapped(pcap_t *p) |
| { |
| return (p->sf.swapped); |
| } |
| |
| int |
| pcap_major_version(pcap_t *p) |
| { |
| return (p->sf.version_major); |
| } |
| |
| int |
| pcap_minor_version(pcap_t *p) |
| { |
| return (p->sf.version_minor); |
| } |
| |
| FILE * |
| pcap_file(pcap_t *p) |
| { |
| return (p->sf.rfile); |
| } |
| |
| int |
| pcap_fileno(pcap_t *p) |
| { |
| #ifndef WIN32 |
| return (p->fd); |
| #else |
| if (p->adapter != NULL) |
| return ((int)(DWORD)p->adapter->hFile); |
| else |
| return (-1); |
| #endif |
| } |
| |
| void |
| pcap_perror(pcap_t *p, char *prefix) |
| { |
| fprintf(stderr, "%s: %s\n", prefix, p->errbuf); |
| } |
| |
| char * |
| pcap_geterr(pcap_t *p) |
| { |
| return (p->errbuf); |
| } |
| |
| /* |
| * NOTE: in the future, these may need to call platform-dependent routines, |
| * e.g. on platforms with memory-mapped packet-capture mechanisms where |
| * "pcap_read()" uses "select()" or "poll()" to wait for packets to arrive. |
| */ |
| int |
| pcap_getnonblock(pcap_t *p, char *errbuf) |
| { |
| #ifndef WIN32 |
| int fdflags; |
| #endif |
| |
| if (p->sf.rfile != NULL) { |
| /* |
| * This is a savefile, not a live capture file, so |
| * never say it's in non-blocking mode. |
| */ |
| return (0); |
| } |
| #ifndef WIN32 |
| fdflags = fcntl(p->fd, F_GETFL, 0); |
| if (fdflags == -1) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_GETFL: %s", |
| pcap_strerror(errno)); |
| return (-1); |
| } |
| if (fdflags & O_NONBLOCK) |
| return (1); |
| else |
| return (0); |
| #else |
| return (p->nonblock); |
| #endif |
| } |
| |
| int |
| pcap_setnonblock(pcap_t *p, int nonblock, char *errbuf) |
| { |
| #ifndef WIN32 |
| int fdflags; |
| #else |
| int newtimeout; |
| #endif |
| |
| if (p->sf.rfile != NULL) { |
| /* |
| * This is a savefile, not a live capture file, so |
| * ignore requests to put it in non-blocking mode. |
| */ |
| return (0); |
| } |
| #ifndef WIN32 |
| fdflags = fcntl(p->fd, F_GETFL, 0); |
| if (fdflags == -1) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_GETFL: %s", |
| pcap_strerror(errno)); |
| return (-1); |
| } |
| if (nonblock) |
| fdflags |= O_NONBLOCK; |
| else |
| fdflags &= ~O_NONBLOCK; |
| if (fcntl(p->fd, F_SETFL, fdflags) == -1) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_SETFL: %s", |
| pcap_strerror(errno)); |
| return (-1); |
| } |
| #else |
| if (nonblock) { |
| /* |
| * Set the read timeout to -1 for non-blocking mode. |
| */ |
| newtimeout = -1; |
| } else { |
| /* |
| * Restore the timeout set when the device was opened. |
| * (Note that this may be -1, in which case we're not |
| * really leaving non-blocking mode.) |
| */ |
| newtimeout = p->timeout; |
| } |
| if (!PacketSetReadTimeout(p->adapter, newtimeout)) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "PacketSetReadTimeout: %s", pcap_win32strerror()); |
| return (-1); |
| } |
| p->nonblock = (newtimeout == -1); |
| #endif |
| return (0); |
| } |
| |
| #ifdef WIN32 |
| /* |
| * Generate a string for the last Win32-specific error (i.e. an error generated when |
| * calling a Win32 API). |
| * For errors occurred during standard C calls, we still use pcap_strerror() |
| */ |
| char * |
| pcap_win32strerror(void) |
| { |
| DWORD error; |
| static char errbuf[PCAP_ERRBUF_SIZE+1]; |
| int errlen; |
| |
| error = GetLastError(); |
| FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, error, 0, errbuf, |
| PCAP_ERRBUF_SIZE, NULL); |
| |
| /* |
| * "FormatMessage()" "helpfully" sticks CR/LF at the end of the |
| * message. Get rid of it. |
| */ |
| errlen = strlen(errbuf); |
| if (errlen >= 2) { |
| errbuf[errlen - 1] = '\0'; |
| errbuf[errlen - 2] = '\0'; |
| } |
| return (errbuf); |
| } |
| #endif |
| |
| /* |
| * Not all systems have strerror(). |
| */ |
| char * |
| pcap_strerror(int errnum) |
| { |
| #ifdef HAVE_STRERROR |
| return (strerror(errnum)); |
| #else |
| extern int sys_nerr; |
| extern const char *const sys_errlist[]; |
| static char ebuf[20]; |
| |
| if ((unsigned int)errnum < sys_nerr) |
| return ((char *)sys_errlist[errnum]); |
| (void)snprintf(ebuf, sizeof ebuf, "Unknown error: %d", errnum); |
| return(ebuf); |
| #endif |
| } |
| |
| pcap_t * |
| pcap_open_dead(int linktype, int snaplen) |
| { |
| pcap_t *p; |
| |
| p = malloc(sizeof(*p)); |
| if (p == NULL) |
| return NULL; |
| memset (p, 0, sizeof(*p)); |
| #ifndef WIN32 |
| p->fd = -1; |
| #else |
| p->adapter = NULL; |
| #endif /* WIN32 */ |
| p->snapshot = snaplen; |
| p->linktype = linktype; |
| return p; |
| } |
| |
| void |
| pcap_close(pcap_t *p) |
| { |
| /*XXX*/ |
| #ifndef WIN32 |
| if (p->fd >= 0) { |
| #ifdef linux |
| pcap_close_linux(p); |
| #endif |
| close(p->fd); |
| } |
| #else /* WIN32 */ |
| if (p->adapter != NULL) { |
| PacketCloseAdapter(p->adapter); |
| p->adapter = NULL; |
| } |
| #endif /* WIN32 */ |
| if (p->sf.rfile != NULL) { |
| if (p->sf.rfile != stdin) |
| (void)fclose(p->sf.rfile); |
| if (p->sf.base != NULL) |
| free(p->sf.base); |
| } else if (p->buffer != NULL) |
| free(p->buffer); |
| |
| pcap_freecode(&p->fcode); |
| free(p); |
| } |