| /* |
| * Copyright (c) 1993, 1994, 1995, 1996, 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: (1) source code distributions |
| * retain the above copyright notice and this paragraph in its entirety, (2) |
| * distributions including binary code include the above copyright notice and |
| * this paragraph in its entirety in the documentation or other materials |
| * provided with the distribution, and (3) all advertising materials mentioning |
| * features or use of this software display the following acknowledgement: |
| * ``This product includes software developed by the University of California, |
| * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of |
| * the University nor the names of its contributors may be used to endorse |
| * or promote products derived from this software without specific prior |
| * written permission. |
| * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED |
| * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
| */ |
| #ifndef lint |
| static const char rcsid[] _U_ = |
| "@(#) $Header: /tcpdump/master/libpcap/pcap-bpf.c,v 1.116 2008-09-16 18:42:29 guy Exp $ (LBL)"; |
| #endif |
| |
| #ifdef HAVE_CONFIG_H |
| #include "config.h" |
| #endif |
| |
| #include <sys/param.h> /* optionally get BSD define */ |
| #ifdef HAVE_ZEROCOPY_BPF |
| #include <sys/mman.h> |
| #endif |
| #include <sys/socket.h> |
| #include <time.h> |
| /* |
| * <net/bpf.h> defines ioctls, but doesn't include <sys/ioccom.h>. |
| * |
| * We include <sys/ioctl.h> as it might be necessary to declare ioctl(); |
| * at least on *BSD and Mac OS X, it also defines various SIOC ioctls - |
| * we could include <sys/sockio.h>, but if we're already including |
| * <sys/ioctl.h>, which includes <sys/sockio.h> on those platforms, |
| * there's not much point in doing so. |
| * |
| * If we have <sys/ioccom.h>, we include it as well, to handle systems |
| * such as Solaris which don't arrange to include <sys/ioccom.h> if you |
| * include <sys/ioctl.h> |
| */ |
| #include <sys/ioctl.h> |
| #ifdef HAVE_SYS_IOCCOM_H |
| #include <sys/ioccom.h> |
| #endif |
| #include <sys/utsname.h> |
| |
| #ifdef HAVE_ZEROCOPY_BPF |
| #include <machine/atomic.h> |
| #endif |
| |
| #include <net/if.h> |
| |
| #ifdef _AIX |
| |
| /* |
| * Make "pcap.h" not include "pcap/bpf.h"; we are going to include the |
| * native OS version, as we need "struct bpf_config" from it. |
| */ |
| #define PCAP_DONT_INCLUDE_PCAP_BPF_H |
| |
| #include <sys/types.h> |
| |
| /* |
| * Prevent bpf.h from redefining the DLT_ values to their |
| * IFT_ values, as we're going to return the standard libpcap |
| * values, not IBM's non-standard IFT_ values. |
| */ |
| #undef _AIX |
| #include <net/bpf.h> |
| #define _AIX |
| |
| #include <net/if_types.h> /* for IFT_ values */ |
| #include <sys/sysconfig.h> |
| #include <sys/device.h> |
| #include <sys/cfgodm.h> |
| #include <cf.h> |
| |
| #ifdef __64BIT__ |
| #define domakedev makedev64 |
| #define getmajor major64 |
| #define bpf_hdr bpf_hdr32 |
| #else /* __64BIT__ */ |
| #define domakedev makedev |
| #define getmajor major |
| #endif /* __64BIT__ */ |
| |
| #define BPF_NAME "bpf" |
| #define BPF_MINORS 4 |
| #define DRIVER_PATH "/usr/lib/drivers" |
| #define BPF_NODE "/dev/bpf" |
| static int bpfloadedflag = 0; |
| static int odmlockid = 0; |
| |
| static int bpf_load(char *errbuf); |
| |
| #else /* _AIX */ |
| |
| #include <net/bpf.h> |
| |
| #endif /* _AIX */ |
| |
| #include <ctype.h> |
| #include <fcntl.h> |
| #include <errno.h> |
| #include <netdb.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <unistd.h> |
| |
| #ifdef HAVE_NET_IF_MEDIA_H |
| # include <net/if_media.h> |
| #endif |
| |
| #include "pcap-int.h" |
| |
| #ifdef HAVE_DAG_API |
| #include "pcap-dag.h" |
| #endif /* HAVE_DAG_API */ |
| |
| #ifdef HAVE_SNF_API |
| #include "pcap-snf.h" |
| #endif /* HAVE_SNF_API */ |
| |
| #ifdef HAVE_OS_PROTO_H |
| #include "os-proto.h" |
| #endif |
| |
| #ifdef BIOCGDLTLIST |
| # if (defined(HAVE_NET_IF_MEDIA_H) && defined(IFM_IEEE80211)) && !defined(__APPLE__) |
| #define HAVE_BSD_IEEE80211 |
| # endif |
| |
| # if defined(__APPLE__) || defined(HAVE_BSD_IEEE80211) |
| static int find_802_11(struct bpf_dltlist *); |
| |
| # ifdef HAVE_BSD_IEEE80211 |
| static int monitor_mode(pcap_t *, int); |
| # endif |
| |
| # if defined(__APPLE__) |
| static void remove_en(pcap_t *); |
| static void remove_802_11(pcap_t *); |
| # endif |
| |
| # endif /* defined(__APPLE__) || defined(HAVE_BSD_IEEE80211) */ |
| |
| #endif /* BIOCGDLTLIST */ |
| |
| #if defined(sun) && defined(LIFNAMSIZ) && defined(lifr_zoneid) |
| #include <zone.h> |
| #endif |
| |
| /* |
| * We include the OS's <net/bpf.h>, not our "pcap/bpf.h", so we probably |
| * don't get DLT_DOCSIS defined. |
| */ |
| #ifndef DLT_DOCSIS |
| #define DLT_DOCSIS 143 |
| #endif |
| |
| /* |
| * On OS X, we don't even get any of the 802.11-plus-radio-header DLT_'s |
| * defined, even though some of them are used by various Airport drivers. |
| */ |
| #ifndef DLT_PRISM_HEADER |
| #define DLT_PRISM_HEADER 119 |
| #endif |
| #ifndef DLT_AIRONET_HEADER |
| #define DLT_AIRONET_HEADER 120 |
| #endif |
| #ifndef DLT_IEEE802_11_RADIO |
| #define DLT_IEEE802_11_RADIO 127 |
| #endif |
| #ifndef DLT_IEEE802_11_RADIO_AVS |
| #define DLT_IEEE802_11_RADIO_AVS 163 |
| #endif |
| |
| static int pcap_can_set_rfmon_bpf(pcap_t *p); |
| static int pcap_activate_bpf(pcap_t *p); |
| static int pcap_setfilter_bpf(pcap_t *p, struct bpf_program *fp); |
| static int pcap_setdirection_bpf(pcap_t *, pcap_direction_t); |
| static int pcap_set_datalink_bpf(pcap_t *p, int dlt); |
| |
| /* |
| * For zerocopy bpf, the setnonblock/getnonblock routines need to modify |
| * p->md.timeout so we don't call select(2) if the pcap handle is in non- |
| * blocking mode. We preserve the timeout supplied by pcap_open functions |
| * to make sure it does not get clobbered if the pcap handle moves between |
| * blocking and non-blocking mode. |
| */ |
| static int |
| pcap_getnonblock_bpf(pcap_t *p, char *errbuf) |
| { |
| #ifdef HAVE_ZEROCOPY_BPF |
| if (p->md.zerocopy) { |
| /* |
| * Use a negative value for the timeout to represent that the |
| * pcap handle is in non-blocking mode. |
| */ |
| return (p->md.timeout < 0); |
| } |
| #endif |
| return (pcap_getnonblock_fd(p, errbuf)); |
| } |
| |
| static int |
| pcap_setnonblock_bpf(pcap_t *p, int nonblock, char *errbuf) |
| { |
| #ifdef HAVE_ZEROCOPY_BPF |
| if (p->md.zerocopy) { |
| /* |
| * Map each value to the corresponding 2's complement, to |
| * preserve the timeout value provided with pcap_set_timeout. |
| * (from pcap-linux.c). |
| */ |
| if (nonblock) { |
| if (p->md.timeout >= 0) { |
| /* |
| * Timeout is non-negative, so we're not |
| * currently in non-blocking mode; set it |
| * to the 2's complement, to make it |
| * negative, as an indication that we're |
| * in non-blocking mode. |
| */ |
| p->md.timeout = p->md.timeout * -1 - 1; |
| } |
| } else { |
| if (p->md.timeout < 0) { |
| /* |
| * Timeout is negative, so we're currently |
| * in blocking mode; reverse the previous |
| * operation, to make the timeout non-negative |
| * again. |
| */ |
| p->md.timeout = (p->md.timeout + 1) * -1; |
| } |
| } |
| return (0); |
| } |
| #endif |
| return (pcap_setnonblock_fd(p, nonblock, errbuf)); |
| } |
| |
| #ifdef HAVE_ZEROCOPY_BPF |
| /* |
| * Zero-copy BPF buffer routines to check for and acknowledge BPF data in |
| * shared memory buffers. |
| * |
| * pcap_next_zbuf_shm(): Check for a newly available shared memory buffer, |
| * and set up p->buffer and cc to reflect one if available. Notice that if |
| * there was no prior buffer, we select zbuf1 as this will be the first |
| * buffer filled for a fresh BPF session. |
| */ |
| static int |
| pcap_next_zbuf_shm(pcap_t *p, int *cc) |
| { |
| struct bpf_zbuf_header *bzh; |
| |
| if (p->md.zbuffer == p->md.zbuf2 || p->md.zbuffer == NULL) { |
| bzh = (struct bpf_zbuf_header *)p->md.zbuf1; |
| if (bzh->bzh_user_gen != |
| atomic_load_acq_int(&bzh->bzh_kernel_gen)) { |
| p->md.bzh = bzh; |
| p->md.zbuffer = (u_char *)p->md.zbuf1; |
| p->buffer = p->md.zbuffer + sizeof(*bzh); |
| *cc = bzh->bzh_kernel_len; |
| return (1); |
| } |
| } else if (p->md.zbuffer == p->md.zbuf1) { |
| bzh = (struct bpf_zbuf_header *)p->md.zbuf2; |
| if (bzh->bzh_user_gen != |
| atomic_load_acq_int(&bzh->bzh_kernel_gen)) { |
| p->md.bzh = bzh; |
| p->md.zbuffer = (u_char *)p->md.zbuf2; |
| p->buffer = p->md.zbuffer + sizeof(*bzh); |
| *cc = bzh->bzh_kernel_len; |
| return (1); |
| } |
| } |
| *cc = 0; |
| return (0); |
| } |
| |
| /* |
| * pcap_next_zbuf() -- Similar to pcap_next_zbuf_shm(), except wait using |
| * select() for data or a timeout, and possibly force rotation of the buffer |
| * in the event we time out or are in immediate mode. Invoke the shared |
| * memory check before doing system calls in order to avoid doing avoidable |
| * work. |
| */ |
| static int |
| pcap_next_zbuf(pcap_t *p, int *cc) |
| { |
| struct bpf_zbuf bz; |
| struct timeval tv; |
| struct timespec cur; |
| fd_set r_set; |
| int data, r; |
| int expire, tmout; |
| |
| #define TSTOMILLI(ts) (((ts)->tv_sec * 1000) + ((ts)->tv_nsec / 1000000)) |
| /* |
| * Start out by seeing whether anything is waiting by checking the |
| * next shared memory buffer for data. |
| */ |
| data = pcap_next_zbuf_shm(p, cc); |
| if (data) |
| return (data); |
| /* |
| * If a previous sleep was interrupted due to signal delivery, make |
| * sure that the timeout gets adjusted accordingly. This requires |
| * that we analyze when the timeout should be been expired, and |
| * subtract the current time from that. If after this operation, |
| * our timeout is less then or equal to zero, handle it like a |
| * regular timeout. |
| */ |
| tmout = p->md.timeout; |
| if (tmout) |
| (void) clock_gettime(CLOCK_MONOTONIC, &cur); |
| if (p->md.interrupted && p->md.timeout) { |
| expire = TSTOMILLI(&p->md.firstsel) + p->md.timeout; |
| tmout = expire - TSTOMILLI(&cur); |
| #undef TSTOMILLI |
| if (tmout <= 0) { |
| p->md.interrupted = 0; |
| data = pcap_next_zbuf_shm(p, cc); |
| if (data) |
| return (data); |
| if (ioctl(p->fd, BIOCROTZBUF, &bz) < 0) { |
| (void) snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "BIOCROTZBUF: %s", strerror(errno)); |
| return (PCAP_ERROR); |
| } |
| return (pcap_next_zbuf_shm(p, cc)); |
| } |
| } |
| /* |
| * No data in the buffer, so must use select() to wait for data or |
| * the next timeout. Note that we only call select if the handle |
| * is in blocking mode. |
| */ |
| if (p->md.timeout >= 0) { |
| FD_ZERO(&r_set); |
| FD_SET(p->fd, &r_set); |
| if (tmout != 0) { |
| tv.tv_sec = tmout / 1000; |
| tv.tv_usec = (tmout * 1000) % 1000000; |
| } |
| r = select(p->fd + 1, &r_set, NULL, NULL, |
| p->md.timeout != 0 ? &tv : NULL); |
| if (r < 0 && errno == EINTR) { |
| if (!p->md.interrupted && p->md.timeout) { |
| p->md.interrupted = 1; |
| p->md.firstsel = cur; |
| } |
| return (0); |
| } else if (r < 0) { |
| (void) snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "select: %s", strerror(errno)); |
| return (PCAP_ERROR); |
| } |
| } |
| p->md.interrupted = 0; |
| /* |
| * Check again for data, which may exist now that we've either been |
| * woken up as a result of data or timed out. Try the "there's data" |
| * case first since it doesn't require a system call. |
| */ |
| data = pcap_next_zbuf_shm(p, cc); |
| if (data) |
| return (data); |
| /* |
| * Try forcing a buffer rotation to dislodge timed out or immediate |
| * data. |
| */ |
| if (ioctl(p->fd, BIOCROTZBUF, &bz) < 0) { |
| (void) snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "BIOCROTZBUF: %s", strerror(errno)); |
| return (PCAP_ERROR); |
| } |
| return (pcap_next_zbuf_shm(p, cc)); |
| } |
| |
| /* |
| * Notify kernel that we are done with the buffer. We don't reset zbuffer so |
| * that we know which buffer to use next time around. |
| */ |
| static int |
| pcap_ack_zbuf(pcap_t *p) |
| { |
| |
| atomic_store_rel_int(&p->md.bzh->bzh_user_gen, |
| p->md.bzh->bzh_kernel_gen); |
| p->md.bzh = NULL; |
| p->buffer = NULL; |
| return (0); |
| } |
| #endif /* HAVE_ZEROCOPY_BPF */ |
| |
| pcap_t * |
| pcap_create(const char *device, char *ebuf) |
| { |
| pcap_t *p; |
| |
| #ifdef HAVE_DAG_API |
| if (strstr(device, "dag")) |
| return (dag_create(device, ebuf)); |
| #endif /* HAVE_DAG_API */ |
| #ifdef HAVE_SNF_API |
| if (strstr(device, "snf")) |
| return (snf_create(device, ebuf)); |
| #endif /* HAVE_SNF_API */ |
| |
| p = pcap_create_common(device, ebuf); |
| if (p == NULL) |
| return (NULL); |
| |
| p->activate_op = pcap_activate_bpf; |
| p->can_set_rfmon_op = pcap_can_set_rfmon_bpf; |
| return (p); |
| } |
| |
| /* |
| * On success, returns a file descriptor for a BPF device. |
| * On failure, returns a PCAP_ERROR_ value, and sets p->errbuf. |
| */ |
| static int |
| bpf_open(pcap_t *p) |
| { |
| int fd; |
| #ifdef HAVE_CLONING_BPF |
| static const char device[] = "/dev/bpf"; |
| #else |
| int n = 0; |
| char device[sizeof "/dev/bpf0000000000"]; |
| #endif |
| |
| #ifdef _AIX |
| /* |
| * Load the bpf driver, if it isn't already loaded, |
| * and create the BPF device entries, if they don't |
| * already exist. |
| */ |
| if (bpf_load(p->errbuf) == PCAP_ERROR) |
| return (PCAP_ERROR); |
| #endif |
| |
| #ifdef HAVE_CLONING_BPF |
| if ((fd = open(device, O_RDWR)) == -1 && |
| (errno != EACCES || (fd = open(device, O_RDONLY)) == -1)) { |
| if (errno == EACCES) |
| fd = PCAP_ERROR_PERM_DENIED; |
| else |
| fd = PCAP_ERROR; |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "(cannot open device) %s: %s", device, pcap_strerror(errno)); |
| } |
| #else |
| /* |
| * Go through all the minors and find one that isn't in use. |
| */ |
| do { |
| (void)snprintf(device, sizeof(device), "/dev/bpf%d", n++); |
| /* |
| * Initially try a read/write open (to allow the inject |
| * method to work). If that fails due to permission |
| * issues, fall back to read-only. This allows a |
| * non-root user to be granted specific access to pcap |
| * capabilities via file permissions. |
| * |
| * XXX - we should have an API that has a flag that |
| * controls whether to open read-only or read-write, |
| * so that denial of permission to send (or inability |
| * to send, if sending packets isn't supported on |
| * the device in question) can be indicated at open |
| * time. |
| */ |
| fd = open(device, O_RDWR); |
| if (fd == -1 && errno == EACCES) |
| fd = open(device, O_RDONLY); |
| } while (fd < 0 && errno == EBUSY); |
| |
| /* |
| * XXX better message for all minors used |
| */ |
| if (fd < 0) { |
| switch (errno) { |
| |
| case ENOENT: |
| fd = PCAP_ERROR; |
| if (n == 1) { |
| /* |
| * /dev/bpf0 doesn't exist, which |
| * means we probably have no BPF |
| * devices. |
| */ |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "(there are no BPF devices)"); |
| } else { |
| /* |
| * We got EBUSY on at least one |
| * BPF device, so we have BPF |
| * devices, but all the ones |
| * that exist are busy. |
| */ |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "(all BPF devices are busy)"); |
| } |
| break; |
| |
| case EACCES: |
| /* |
| * Got EACCES on the last device we tried, |
| * and EBUSY on all devices before that, |
| * if any. |
| */ |
| fd = PCAP_ERROR_PERM_DENIED; |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "(cannot open BPF device) %s: %s", device, |
| pcap_strerror(errno)); |
| break; |
| |
| default: |
| /* |
| * Some other problem. |
| */ |
| fd = PCAP_ERROR; |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "(cannot open BPF device) %s: %s", device, |
| pcap_strerror(errno)); |
| break; |
| } |
| } |
| #endif |
| |
| return (fd); |
| } |
| |
| #ifdef BIOCGDLTLIST |
| static int |
| get_dlt_list(int fd, int v, struct bpf_dltlist *bdlp, char *ebuf) |
| { |
| memset(bdlp, 0, sizeof(*bdlp)); |
| if (ioctl(fd, BIOCGDLTLIST, (caddr_t)bdlp) == 0) { |
| u_int i; |
| int is_ethernet; |
| |
| bdlp->bfl_list = (u_int *) malloc(sizeof(u_int) * (bdlp->bfl_len + 1)); |
| if (bdlp->bfl_list == NULL) { |
| (void)snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s", |
| pcap_strerror(errno)); |
| return (PCAP_ERROR); |
| } |
| |
| if (ioctl(fd, BIOCGDLTLIST, (caddr_t)bdlp) < 0) { |
| (void)snprintf(ebuf, PCAP_ERRBUF_SIZE, |
| "BIOCGDLTLIST: %s", pcap_strerror(errno)); |
| free(bdlp->bfl_list); |
| return (PCAP_ERROR); |
| } |
| |
| /* |
| * OK, for real Ethernet devices, add DLT_DOCSIS to the |
| * list, so that an application can let you choose it, |
| * in case you're capturing DOCSIS traffic that a Cisco |
| * Cable Modem Termination System is putting out onto |
| * an Ethernet (it doesn't put an Ethernet header onto |
| * the wire, it puts raw DOCSIS frames out on the wire |
| * inside the low-level Ethernet framing). |
| * |
| * A "real Ethernet device" is defined here as a device |
| * that has a link-layer type of DLT_EN10MB and that has |
| * no alternate link-layer types; that's done to exclude |
| * 802.11 interfaces (which might or might not be the |
| * right thing to do, but I suspect it is - Ethernet <-> |
| * 802.11 bridges would probably badly mishandle frames |
| * that don't have Ethernet headers). |
| * |
| * On Solaris with BPF, Ethernet devices also offer |
| * DLT_IPNET, so we, if DLT_IPNET is defined, we don't |
| * treat it as an indication that the device isn't an |
| * Ethernet. |
| */ |
| if (v == DLT_EN10MB) { |
| is_ethernet = 1; |
| for (i = 0; i < bdlp->bfl_len; i++) { |
| if (bdlp->bfl_list[i] != DLT_EN10MB |
| #ifdef DLT_IPNET |
| && bdlp->bfl_list[i] != DLT_IPNET |
| #endif |
| ) { |
| is_ethernet = 0; |
| break; |
| } |
| } |
| if (is_ethernet) { |
| /* |
| * We reserved one more slot at the end of |
| * the list. |
| */ |
| bdlp->bfl_list[bdlp->bfl_len] = DLT_DOCSIS; |
| bdlp->bfl_len++; |
| } |
| } |
| } else { |
| /* |
| * EINVAL just means "we don't support this ioctl on |
| * this device"; don't treat it as an error. |
| */ |
| if (errno != EINVAL) { |
| (void)snprintf(ebuf, PCAP_ERRBUF_SIZE, |
| "BIOCGDLTLIST: %s", pcap_strerror(errno)); |
| return (PCAP_ERROR); |
| } |
| } |
| return (0); |
| } |
| #endif |
| |
| static int |
| pcap_can_set_rfmon_bpf(pcap_t *p) |
| { |
| #if defined(__APPLE__) |
| struct utsname osinfo; |
| struct ifreq ifr; |
| int fd; |
| #ifdef BIOCGDLTLIST |
| struct bpf_dltlist bdl; |
| #endif |
| |
| /* |
| * The joys of monitor mode on OS X. |
| * |
| * Prior to 10.4, it's not supported at all. |
| * |
| * In 10.4, if adapter enN supports monitor mode, there's a |
| * wltN adapter corresponding to it; you open it, instead of |
| * enN, to get monitor mode. You get whatever link-layer |
| * headers it supplies. |
| * |
| * In 10.5, and, we assume, later releases, if adapter enN |
| * supports monitor mode, it offers, among its selectable |
| * DLT_ values, values that let you get the 802.11 header; |
| * selecting one of those values puts the adapter into monitor |
| * mode (i.e., you can't get 802.11 headers except in monitor |
| * mode, and you can't get Ethernet headers in monitor mode). |
| */ |
| if (uname(&osinfo) == -1) { |
| /* |
| * Can't get the OS version; just say "no". |
| */ |
| return (0); |
| } |
| /* |
| * We assume osinfo.sysname is "Darwin", because |
| * __APPLE__ is defined. We just check the version. |
| */ |
| if (osinfo.release[0] < '8' && osinfo.release[1] == '.') { |
| /* |
| * 10.3 (Darwin 7.x) or earlier. |
| * Monitor mode not supported. |
| */ |
| return (0); |
| } |
| if (osinfo.release[0] == '8' && osinfo.release[1] == '.') { |
| /* |
| * 10.4 (Darwin 8.x). s/en/wlt/, and check |
| * whether the device exists. |
| */ |
| if (strncmp(p->opt.source, "en", 2) != 0) { |
| /* |
| * Not an enN device; no monitor mode. |
| */ |
| return (0); |
| } |
| fd = socket(AF_INET, SOCK_DGRAM, 0); |
| if (fd == -1) { |
| (void)snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "socket: %s", pcap_strerror(errno)); |
| return (PCAP_ERROR); |
| } |
| strlcpy(ifr.ifr_name, "wlt", sizeof(ifr.ifr_name)); |
| strlcat(ifr.ifr_name, p->opt.source + 2, sizeof(ifr.ifr_name)); |
| if (ioctl(fd, SIOCGIFFLAGS, (char *)&ifr) < 0) { |
| /* |
| * No such device? |
| */ |
| close(fd); |
| return (0); |
| } |
| close(fd); |
| return (1); |
| } |
| |
| #ifdef BIOCGDLTLIST |
| /* |
| * Everything else is 10.5 or later; for those, |
| * we just open the enN device, and check whether |
| * we have any 802.11 devices. |
| * |
| * First, open a BPF device. |
| */ |
| fd = bpf_open(p); |
| if (fd < 0) |
| return (fd); /* fd is the appropriate error code */ |
| |
| /* |
| * Now bind to the device. |
| */ |
| (void)strncpy(ifr.ifr_name, p->opt.source, sizeof(ifr.ifr_name)); |
| if (ioctl(fd, BIOCSETIF, (caddr_t)&ifr) < 0) { |
| switch (errno) { |
| |
| case ENXIO: |
| /* |
| * There's no such device. |
| */ |
| close(fd); |
| return (PCAP_ERROR_NO_SUCH_DEVICE); |
| |
| case ENETDOWN: |
| /* |
| * Return a "network down" indication, so that |
| * the application can report that rather than |
| * saying we had a mysterious failure and |
| * suggest that they report a problem to the |
| * libpcap developers. |
| */ |
| close(fd); |
| return (PCAP_ERROR_IFACE_NOT_UP); |
| |
| default: |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "BIOCSETIF: %s: %s", |
| p->opt.source, pcap_strerror(errno)); |
| close(fd); |
| return (PCAP_ERROR); |
| } |
| } |
| |
| /* |
| * We know the default link type -- now determine all the DLTs |
| * this interface supports. If this fails with EINVAL, it's |
| * not fatal; we just don't get to use the feature later. |
| * (We don't care about DLT_DOCSIS, so we pass DLT_NULL |
| * as the default DLT for this adapter.) |
| */ |
| if (get_dlt_list(fd, DLT_NULL, &bdl, p->errbuf) == PCAP_ERROR) { |
| close(fd); |
| return (PCAP_ERROR); |
| } |
| if (find_802_11(&bdl) != -1) { |
| /* |
| * We have an 802.11 DLT, so we can set monitor mode. |
| */ |
| free(bdl.bfl_list); |
| close(fd); |
| return (1); |
| } |
| free(bdl.bfl_list); |
| #endif /* BIOCGDLTLIST */ |
| return (0); |
| #elif defined(HAVE_BSD_IEEE80211) |
| int ret; |
| |
| ret = monitor_mode(p, 0); |
| if (ret == PCAP_ERROR_RFMON_NOTSUP) |
| return (0); /* not an error, just a "can't do" */ |
| if (ret == 0) |
| return (1); /* success */ |
| return (ret); |
| #else |
| return (0); |
| #endif |
| } |
| |
| static int |
| pcap_stats_bpf(pcap_t *p, struct pcap_stat *ps) |
| { |
| struct bpf_stat s; |
| |
| /* |
| * "ps_recv" counts packets handed to the filter, not packets |
| * that passed the filter. This includes packets later dropped |
| * because we ran out of buffer space. |
| * |
| * "ps_drop" counts packets dropped inside the BPF device |
| * because we ran out of buffer space. It doesn't count |
| * packets dropped by the interface driver. It counts |
| * only packets that passed the filter. |
| * |
| * Both statistics include packets not yet read from the kernel |
| * by libpcap, and thus not yet seen by the application. |
| */ |
| if (ioctl(p->fd, BIOCGSTATS, (caddr_t)&s) < 0) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCGSTATS: %s", |
| pcap_strerror(errno)); |
| return (PCAP_ERROR); |
| } |
| |
| ps->ps_recv = s.bs_recv; |
| ps->ps_drop = s.bs_drop; |
| ps->ps_ifdrop = 0; |
| return (0); |
| } |
| |
| static int |
| pcap_read_bpf(pcap_t *p, int cnt, pcap_handler callback, u_char *user) |
| { |
| int cc; |
| int n = 0; |
| register u_char *bp, *ep; |
| u_char *datap; |
| #ifdef PCAP_FDDIPAD |
| register int pad; |
| #endif |
| #ifdef HAVE_ZEROCOPY_BPF |
| int i; |
| #endif |
| |
| again: |
| /* |
| * Has "pcap_breakloop()" been called? |
| */ |
| if (p->break_loop) { |
| /* |
| * Yes - clear the flag that indicates that it |
| * has, and return PCAP_ERROR_BREAK to indicate |
| * that we were told to break out of the loop. |
| */ |
| p->break_loop = 0; |
| return (PCAP_ERROR_BREAK); |
| } |
| cc = p->cc; |
| if (p->cc == 0) { |
| /* |
| * When reading without zero-copy from a file descriptor, we |
| * use a single buffer and return a length of data in the |
| * buffer. With zero-copy, we update the p->buffer pointer |
| * to point at whatever underlying buffer contains the next |
| * data and update cc to reflect the data found in the |
| * buffer. |
| */ |
| #ifdef HAVE_ZEROCOPY_BPF |
| if (p->md.zerocopy) { |
| if (p->buffer != NULL) |
| pcap_ack_zbuf(p); |
| i = pcap_next_zbuf(p, &cc); |
| if (i == 0) |
| goto again; |
| if (i < 0) |
| return (PCAP_ERROR); |
| } else |
| #endif |
| { |
| cc = read(p->fd, (char *)p->buffer, p->bufsize); |
| } |
| if (cc < 0) { |
| /* Don't choke when we get ptraced */ |
| switch (errno) { |
| |
| case EINTR: |
| goto again; |
| |
| #ifdef _AIX |
| case EFAULT: |
| /* |
| * Sigh. More AIX wonderfulness. |
| * |
| * For some unknown reason the uiomove() |
| * operation in the bpf kernel extension |
| * used to copy the buffer into user |
| * space sometimes returns EFAULT. I have |
| * no idea why this is the case given that |
| * a kernel debugger shows the user buffer |
| * is correct. This problem appears to |
| * be mostly mitigated by the memset of |
| * the buffer before it is first used. |
| * Very strange.... Shaun Clowes |
| * |
| * In any case this means that we shouldn't |
| * treat EFAULT as a fatal error; as we |
| * don't have an API for returning |
| * a "some packets were dropped since |
| * the last packet you saw" indication, |
| * we just ignore EFAULT and keep reading. |
| */ |
| goto again; |
| #endif |
| |
| case EWOULDBLOCK: |
| return (0); |
| |
| case ENXIO: |
| /* |
| * The device on which we're capturing |
| * went away. |
| * |
| * XXX - we should really return |
| * PCAP_ERROR_IFACE_NOT_UP, but |
| * pcap_dispatch() etc. aren't |
| * defined to retur that. |
| */ |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "The interface went down"); |
| return (PCAP_ERROR); |
| |
| #if defined(sun) && !defined(BSD) && !defined(__svr4__) && !defined(__SVR4) |
| /* |
| * Due to a SunOS bug, after 2^31 bytes, the kernel |
| * file offset overflows and read fails with EINVAL. |
| * The lseek() to 0 will fix things. |
| */ |
| case EINVAL: |
| if (lseek(p->fd, 0L, SEEK_CUR) + |
| p->bufsize < 0) { |
| (void)lseek(p->fd, 0L, SEEK_SET); |
| goto again; |
| } |
| /* fall through */ |
| #endif |
| } |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "read: %s", |
| pcap_strerror(errno)); |
| return (PCAP_ERROR); |
| } |
| bp = p->buffer; |
| } else |
| bp = p->bp; |
| |
| /* |
| * Loop through each packet. |
| */ |
| #define bhp ((struct bpf_hdr *)bp) |
| ep = bp + cc; |
| #ifdef PCAP_FDDIPAD |
| pad = p->fddipad; |
| #endif |
| while (bp < ep) { |
| register int caplen, hdrlen; |
| |
| /* |
| * Has "pcap_breakloop()" been called? |
| * If so, return immediately - if we haven't read any |
| * packets, clear the flag and return PCAP_ERROR_BREAK |
| * to indicate that we were told to break out of the loop, |
| * otherwise leave the flag set, so that the *next* call |
| * will break out of the loop without having read any |
| * packets, and return the number of packets we've |
| * processed so far. |
| */ |
| if (p->break_loop) { |
| p->bp = bp; |
| p->cc = ep - bp; |
| /* |
| * ep is set based on the return value of read(), |
| * but read() from a BPF device doesn't necessarily |
| * return a value that's a multiple of the alignment |
| * value for BPF_WORDALIGN(). However, whenever we |
| * increment bp, we round up the increment value by |
| * a value rounded up by BPF_WORDALIGN(), so we |
| * could increment bp past ep after processing the |
| * last packet in the buffer. |
| * |
| * We treat ep < bp as an indication that this |
| * happened, and just set p->cc to 0. |
| */ |
| if (p->cc < 0) |
| p->cc = 0; |
| if (n == 0) { |
| p->break_loop = 0; |
| return (PCAP_ERROR_BREAK); |
| } else |
| return (n); |
| } |
| |
| caplen = bhp->bh_caplen; |
| hdrlen = bhp->bh_hdrlen; |
| datap = bp + hdrlen; |
| /* |
| * Short-circuit evaluation: if using BPF filter |
| * in kernel, no need to do it now - we already know |
| * the packet passed the filter. |
| * |
| #ifdef PCAP_FDDIPAD |
| * Note: the filter code was generated assuming |
| * that p->fddipad was the amount of padding |
| * before the header, as that's what's required |
| * in the kernel, so we run the filter before |
| * skipping that padding. |
| #endif |
| */ |
| if (p->md.use_bpf || |
| bpf_filter(p->fcode.bf_insns, datap, bhp->bh_datalen, caplen)) { |
| struct pcap_pkthdr pkthdr; |
| |
| pkthdr.ts.tv_sec = bhp->bh_tstamp.tv_sec; |
| #ifdef _AIX |
| /* |
| * AIX's BPF returns seconds/nanoseconds time |
| * stamps, not seconds/microseconds time stamps. |
| */ |
| pkthdr.ts.tv_usec = bhp->bh_tstamp.tv_usec/1000; |
| #else |
| pkthdr.ts.tv_usec = bhp->bh_tstamp.tv_usec; |
| #endif |
| #ifdef PCAP_FDDIPAD |
| if (caplen > pad) |
| pkthdr.caplen = caplen - pad; |
| else |
| pkthdr.caplen = 0; |
| if (bhp->bh_datalen > pad) |
| pkthdr.len = bhp->bh_datalen - pad; |
| else |
| pkthdr.len = 0; |
| datap += pad; |
| #else |
| pkthdr.caplen = caplen; |
| pkthdr.len = bhp->bh_datalen; |
| #endif |
| (*callback)(user, &pkthdr, datap); |
| bp += BPF_WORDALIGN(caplen + hdrlen); |
| if (++n >= cnt && cnt > 0) { |
| p->bp = bp; |
| p->cc = ep - bp; |
| /* |
| * See comment above about p->cc < 0. |
| */ |
| if (p->cc < 0) |
| p->cc = 0; |
| return (n); |
| } |
| } else { |
| /* |
| * Skip this packet. |
| */ |
| bp += BPF_WORDALIGN(caplen + hdrlen); |
| } |
| } |
| #undef bhp |
| p->cc = 0; |
| return (n); |
| } |
| |
| static int |
| pcap_inject_bpf(pcap_t *p, const void *buf, size_t size) |
| { |
| int ret; |
| |
| ret = write(p->fd, buf, size); |
| #ifdef __APPLE__ |
| if (ret == -1 && errno == EAFNOSUPPORT) { |
| /* |
| * In Mac OS X, there's a bug wherein setting the |
| * BIOCSHDRCMPLT flag causes writes to fail; see, |
| * for example: |
| * |
| * http://cerberus.sourcefire.com/~jeff/archives/patches/macosx/BIOCSHDRCMPLT-10.3.3.patch |
| * |
| * So, if, on OS X, we get EAFNOSUPPORT from the write, we |
| * assume it's due to that bug, and turn off that flag |
| * and try again. If we succeed, it either means that |
| * somebody applied the fix from that URL, or other patches |
| * for that bug from |
| * |
| * http://cerberus.sourcefire.com/~jeff/archives/patches/macosx/ |
| * |
| * and are running a Darwin kernel with those fixes, or |
| * that Apple fixed the problem in some OS X release. |
| */ |
| u_int spoof_eth_src = 0; |
| |
| if (ioctl(p->fd, BIOCSHDRCMPLT, &spoof_eth_src) == -1) { |
| (void)snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "send: can't turn off BIOCSHDRCMPLT: %s", |
| pcap_strerror(errno)); |
| return (PCAP_ERROR); |
| } |
| |
| /* |
| * Now try the write again. |
| */ |
| ret = write(p->fd, buf, size); |
| } |
| #endif /* __APPLE__ */ |
| if (ret == -1) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "send: %s", |
| pcap_strerror(errno)); |
| return (PCAP_ERROR); |
| } |
| return (ret); |
| } |
| |
| #ifdef _AIX |
| static int |
| bpf_odminit(char *errbuf) |
| { |
| char *errstr; |
| |
| if (odm_initialize() == -1) { |
| if (odm_err_msg(odmerrno, &errstr) == -1) |
| errstr = "Unknown error"; |
| snprintf(errbuf, PCAP_ERRBUF_SIZE, |
| "bpf_load: odm_initialize failed: %s", |
| errstr); |
| return (PCAP_ERROR); |
| } |
| |
| if ((odmlockid = odm_lock("/etc/objrepos/config_lock", ODM_WAIT)) == -1) { |
| if (odm_err_msg(odmerrno, &errstr) == -1) |
| errstr = "Unknown error"; |
| snprintf(errbuf, PCAP_ERRBUF_SIZE, |
| "bpf_load: odm_lock of /etc/objrepos/config_lock failed: %s", |
| errstr); |
| (void)odm_terminate(); |
| return (PCAP_ERROR); |
| } |
| |
| return (0); |
| } |
| |
| static int |
| bpf_odmcleanup(char *errbuf) |
| { |
| char *errstr; |
| |
| if (odm_unlock(odmlockid) == -1) { |
| if (errbuf != NULL) { |
| if (odm_err_msg(odmerrno, &errstr) == -1) |
| errstr = "Unknown error"; |
| snprintf(errbuf, PCAP_ERRBUF_SIZE, |
| "bpf_load: odm_unlock failed: %s", |
| errstr); |
| } |
| return (PCAP_ERROR); |
| } |
| |
| if (odm_terminate() == -1) { |
| if (errbuf != NULL) { |
| if (odm_err_msg(odmerrno, &errstr) == -1) |
| errstr = "Unknown error"; |
| snprintf(errbuf, PCAP_ERRBUF_SIZE, |
| "bpf_load: odm_terminate failed: %s", |
| errstr); |
| } |
| return (PCAP_ERROR); |
| } |
| |
| return (0); |
| } |
| |
| static int |
| bpf_load(char *errbuf) |
| { |
| long major; |
| int *minors; |
| int numminors, i, rc; |
| char buf[1024]; |
| struct stat sbuf; |
| struct bpf_config cfg_bpf; |
| struct cfg_load cfg_ld; |
| struct cfg_kmod cfg_km; |
| |
| /* |
| * This is very very close to what happens in the real implementation |
| * but I've fixed some (unlikely) bug situations. |
| */ |
| if (bpfloadedflag) |
| return (0); |
| |
| if (bpf_odminit(errbuf) == PCAP_ERROR) |
| return (PCAP_ERROR); |
| |
| major = genmajor(BPF_NAME); |
| if (major == -1) { |
| snprintf(errbuf, PCAP_ERRBUF_SIZE, |
| "bpf_load: genmajor failed: %s", pcap_strerror(errno)); |
| (void)bpf_odmcleanup(NULL); |
| return (PCAP_ERROR); |
| } |
| |
| minors = getminor(major, &numminors, BPF_NAME); |
| if (!minors) { |
| minors = genminor("bpf", major, 0, BPF_MINORS, 1, 1); |
| if (!minors) { |
| snprintf(errbuf, PCAP_ERRBUF_SIZE, |
| "bpf_load: genminor failed: %s", |
| pcap_strerror(errno)); |
| (void)bpf_odmcleanup(NULL); |
| return (PCAP_ERROR); |
| } |
| } |
| |
| if (bpf_odmcleanup(errbuf) == PCAP_ERROR) |
| return (PCAP_ERROR); |
| |
| rc = stat(BPF_NODE "0", &sbuf); |
| if (rc == -1 && errno != ENOENT) { |
| snprintf(errbuf, PCAP_ERRBUF_SIZE, |
| "bpf_load: can't stat %s: %s", |
| BPF_NODE "0", pcap_strerror(errno)); |
| return (PCAP_ERROR); |
| } |
| |
| if (rc == -1 || getmajor(sbuf.st_rdev) != major) { |
| for (i = 0; i < BPF_MINORS; i++) { |
| sprintf(buf, "%s%d", BPF_NODE, i); |
| unlink(buf); |
| if (mknod(buf, S_IRUSR | S_IFCHR, domakedev(major, i)) == -1) { |
| snprintf(errbuf, PCAP_ERRBUF_SIZE, |
| "bpf_load: can't mknod %s: %s", |
| buf, pcap_strerror(errno)); |
| return (PCAP_ERROR); |
| } |
| } |
| } |
| |
| /* Check if the driver is loaded */ |
| memset(&cfg_ld, 0x0, sizeof(cfg_ld)); |
| cfg_ld.path = buf; |
| sprintf(cfg_ld.path, "%s/%s", DRIVER_PATH, BPF_NAME); |
| if ((sysconfig(SYS_QUERYLOAD, (void *)&cfg_ld, sizeof(cfg_ld)) == -1) || |
| (cfg_ld.kmid == 0)) { |
| /* Driver isn't loaded, load it now */ |
| if (sysconfig(SYS_SINGLELOAD, (void *)&cfg_ld, sizeof(cfg_ld)) == -1) { |
| snprintf(errbuf, PCAP_ERRBUF_SIZE, |
| "bpf_load: could not load driver: %s", |
| strerror(errno)); |
| return (PCAP_ERROR); |
| } |
| } |
| |
| /* Configure the driver */ |
| cfg_km.cmd = CFG_INIT; |
| cfg_km.kmid = cfg_ld.kmid; |
| cfg_km.mdilen = sizeof(cfg_bpf); |
| cfg_km.mdiptr = (void *)&cfg_bpf; |
| for (i = 0; i < BPF_MINORS; i++) { |
| cfg_bpf.devno = domakedev(major, i); |
| if (sysconfig(SYS_CFGKMOD, (void *)&cfg_km, sizeof(cfg_km)) == -1) { |
| snprintf(errbuf, PCAP_ERRBUF_SIZE, |
| "bpf_load: could not configure driver: %s", |
| strerror(errno)); |
| return (PCAP_ERROR); |
| } |
| } |
| |
| bpfloadedflag = 1; |
| |
| return (0); |
| } |
| #endif |
| |
| /* |
| * Turn off rfmon mode if necessary. |
| */ |
| static void |
| pcap_cleanup_bpf(pcap_t *p) |
| { |
| #ifdef HAVE_BSD_IEEE80211 |
| int sock; |
| struct ifmediareq req; |
| struct ifreq ifr; |
| #endif |
| |
| if (p->md.must_do_on_close != 0) { |
| /* |
| * There's something we have to do when closing this |
| * pcap_t. |
| */ |
| #ifdef HAVE_BSD_IEEE80211 |
| if (p->md.must_do_on_close & MUST_CLEAR_RFMON) { |
| /* |
| * We put the interface into rfmon mode; |
| * take it out of rfmon mode. |
| * |
| * XXX - if somebody else wants it in rfmon |
| * mode, this code cannot know that, so it'll take |
| * it out of rfmon mode. |
| */ |
| sock = socket(AF_INET, SOCK_DGRAM, 0); |
| if (sock == -1) { |
| fprintf(stderr, |
| "Can't restore interface flags (socket() failed: %s).\n" |
| "Please adjust manually.\n", |
| strerror(errno)); |
| } else { |
| memset(&req, 0, sizeof(req)); |
| strncpy(req.ifm_name, p->md.device, |
| sizeof(req.ifm_name)); |
| if (ioctl(sock, SIOCGIFMEDIA, &req) < 0) { |
| fprintf(stderr, |
| "Can't restore interface flags (SIOCGIFMEDIA failed: %s).\n" |
| "Please adjust manually.\n", |
| strerror(errno)); |
| } else { |
| if (req.ifm_current & IFM_IEEE80211_MONITOR) { |
| /* |
| * Rfmon mode is currently on; |
| * turn it off. |
| */ |
| memset(&ifr, 0, sizeof(ifr)); |
| (void)strncpy(ifr.ifr_name, |
| p->md.device, |
| sizeof(ifr.ifr_name)); |
| ifr.ifr_media = |
| req.ifm_current & ~IFM_IEEE80211_MONITOR; |
| if (ioctl(sock, SIOCSIFMEDIA, |
| &ifr) == -1) { |
| fprintf(stderr, |
| "Can't restore interface flags (SIOCSIFMEDIA failed: %s).\n" |
| "Please adjust manually.\n", |
| strerror(errno)); |
| } |
| } |
| } |
| close(sock); |
| } |
| } |
| #endif /* HAVE_BSD_IEEE80211 */ |
| |
| /* |
| * Take this pcap out of the list of pcaps for which we |
| * have to take the interface out of some mode. |
| */ |
| pcap_remove_from_pcaps_to_close(p); |
| p->md.must_do_on_close = 0; |
| } |
| |
| #ifdef HAVE_ZEROCOPY_BPF |
| if (p->md.zerocopy) { |
| /* |
| * Delete the mappings. Note that p->buffer gets |
| * initialized to one of the mmapped regions in |
| * this case, so do not try and free it directly; |
| * null it out so that pcap_cleanup_live_common() |
| * doesn't try to free it. |
| */ |
| if (p->md.zbuf1 != MAP_FAILED && p->md.zbuf1 != NULL) |
| (void) munmap(p->md.zbuf1, p->md.zbufsize); |
| if (p->md.zbuf2 != MAP_FAILED && p->md.zbuf2 != NULL) |
| (void) munmap(p->md.zbuf2, p->md.zbufsize); |
| p->buffer = NULL; |
| } |
| #endif |
| if (p->md.device != NULL) { |
| free(p->md.device); |
| p->md.device = NULL; |
| } |
| pcap_cleanup_live_common(p); |
| } |
| |
| static int |
| check_setif_failure(pcap_t *p, int error) |
| { |
| #ifdef __APPLE__ |
| int fd; |
| struct ifreq ifr; |
| int err; |
| #endif |
| |
| if (error == ENXIO) { |
| /* |
| * No such device exists. |
| */ |
| #ifdef __APPLE__ |
| if (p->opt.rfmon && strncmp(p->opt.source, "wlt", 3) == 0) { |
| /* |
| * Monitor mode was requested, and we're trying |
| * to open a "wltN" device. Assume that this |
| * is 10.4 and that we were asked to open an |
| * "enN" device; if that device exists, return |
| * "monitor mode not supported on the device". |
| */ |
| fd = socket(AF_INET, SOCK_DGRAM, 0); |
| if (fd != -1) { |
| strlcpy(ifr.ifr_name, "en", |
| sizeof(ifr.ifr_name)); |
| strlcat(ifr.ifr_name, p->opt.source + 3, |
| sizeof(ifr.ifr_name)); |
| if (ioctl(fd, SIOCGIFFLAGS, (char *)&ifr) < 0) { |
| /* |
| * We assume this failed because |
| * the underlying device doesn't |
| * exist. |
| */ |
| err = PCAP_ERROR_NO_SUCH_DEVICE; |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "SIOCGIFFLAGS on %s failed: %s", |
| ifr.ifr_name, pcap_strerror(errno)); |
| } else { |
| /* |
| * The underlying "enN" device |
| * exists, but there's no |
| * corresponding "wltN" device; |
| * that means that the "enN" |
| * device doesn't support |
| * monitor mode, probably because |
| * it's an Ethernet device rather |
| * than a wireless device. |
| */ |
| err = PCAP_ERROR_RFMON_NOTSUP; |
| } |
| close(fd); |
| } else { |
| /* |
| * We can't find out whether there's |
| * an underlying "enN" device, so |
| * just report "no such device". |
| */ |
| err = PCAP_ERROR_NO_SUCH_DEVICE; |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "socket() failed: %s", |
| pcap_strerror(errno)); |
| } |
| return (err); |
| } |
| #endif |
| /* |
| * No such device. |
| */ |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCSETIF failed: %s", |
| pcap_strerror(errno)); |
| return (PCAP_ERROR_NO_SUCH_DEVICE); |
| } else if (errno == ENETDOWN) { |
| /* |
| * Return a "network down" indication, so that |
| * the application can report that rather than |
| * saying we had a mysterious failure and |
| * suggest that they report a problem to the |
| * libpcap developers. |
| */ |
| return (PCAP_ERROR_IFACE_NOT_UP); |
| } else { |
| /* |
| * Some other error; fill in the error string, and |
| * return PCAP_ERROR. |
| */ |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCSETIF: %s: %s", |
| p->opt.source, pcap_strerror(errno)); |
| return (PCAP_ERROR); |
| } |
| } |
| |
| /* |
| * Default capture buffer size. |
| * 32K isn't very much for modern machines with fast networks; we |
| * pick .5M, as that's the maximum on at least some systems with BPF. |
| * |
| * However, on AIX 3.5, the larger buffer sized caused unrecoverable |
| * read failures under stress, so we leave it as 32K; yet another |
| * place where AIX's BPF is broken. |
| */ |
| #ifdef _AIX |
| #define DEFAULT_BUFSIZE 32768 |
| #else |
| #define DEFAULT_BUFSIZE 524288 |
| #endif |
| |
| static int |
| pcap_activate_bpf(pcap_t *p) |
| { |
| int status = 0; |
| int fd; |
| #ifdef LIFNAMSIZ |
| char *zonesep; |
| struct lifreq ifr; |
| char *ifrname = ifr.lifr_name; |
| const size_t ifnamsiz = sizeof(ifr.lifr_name); |
| #else |
| struct ifreq ifr; |
| char *ifrname = ifr.ifr_name; |
| const size_t ifnamsiz = sizeof(ifr.ifr_name); |
| #endif |
| struct bpf_version bv; |
| #ifdef __APPLE__ |
| int sockfd; |
| char *wltdev = NULL; |
| #endif |
| #ifdef BIOCGDLTLIST |
| struct bpf_dltlist bdl; |
| #if defined(__APPLE__) || defined(HAVE_BSD_IEEE80211) |
| int new_dlt; |
| #endif |
| #endif /* BIOCGDLTLIST */ |
| #if defined(BIOCGHDRCMPLT) && defined(BIOCSHDRCMPLT) |
| u_int spoof_eth_src = 1; |
| #endif |
| u_int v; |
| struct bpf_insn total_insn; |
| struct bpf_program total_prog; |
| struct utsname osinfo; |
| int have_osinfo = 0; |
| #ifdef HAVE_ZEROCOPY_BPF |
| struct bpf_zbuf bz; |
| u_int bufmode, zbufmax; |
| #endif |
| |
| fd = bpf_open(p); |
| if (fd < 0) { |
| status = fd; |
| goto bad; |
| } |
| |
| p->fd = fd; |
| |
| if (ioctl(fd, BIOCVERSION, (caddr_t)&bv) < 0) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCVERSION: %s", |
| pcap_strerror(errno)); |
| status = PCAP_ERROR; |
| goto bad; |
| } |
| if (bv.bv_major != BPF_MAJOR_VERSION || |
| bv.bv_minor < BPF_MINOR_VERSION) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "kernel bpf filter out of date"); |
| status = PCAP_ERROR; |
| goto bad; |
| } |
| |
| #if defined(LIFNAMSIZ) && defined(ZONENAME_MAX) && defined(lifr_zoneid) |
| /* |
| * Check if the given source network device has a '/' separated |
| * zonename prefix string. The zonename prefixed source device |
| * can be used by libpcap consumers to capture network traffic |
| * in non-global zones from the global zone on Solaris 11 and |
| * above. If the zonename prefix is present then we strip the |
| * prefix and pass the zone ID as part of lifr_zoneid. |
| */ |
| if ((zonesep = strchr(p->opt.source, '/')) != NULL) { |
| char zonename[ZONENAME_MAX]; |
| int znamelen; |
| char *lnamep; |
| |
| znamelen = zonesep - p->opt.source; |
| (void) strlcpy(zonename, p->opt.source, znamelen + 1); |
| lnamep = strdup(zonesep + 1); |
| ifr.lifr_zoneid = getzoneidbyname(zonename); |
| free(p->opt.source); |
| p->opt.source = lnamep; |
| } |
| #endif |
| |
| p->md.device = strdup(p->opt.source); |
| if (p->md.device == NULL) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "strdup: %s", |
| pcap_strerror(errno)); |
| status = PCAP_ERROR; |
| goto bad; |
| } |
| |
| /* |
| * Attempt to find out the version of the OS on which we're running. |
| */ |
| if (uname(&osinfo) == 0) |
| have_osinfo = 1; |
| |
| #ifdef __APPLE__ |
| /* |
| * See comment in pcap_can_set_rfmon_bpf() for an explanation |
| * of why we check the version number. |
| */ |
| if (p->opt.rfmon) { |
| if (have_osinfo) { |
| /* |
| * We assume osinfo.sysname is "Darwin", because |
| * __APPLE__ is defined. We just check the version. |
| */ |
| if (osinfo.release[0] < '8' && |
| osinfo.release[1] == '.') { |
| /* |
| * 10.3 (Darwin 7.x) or earlier. |
| */ |
| status = PCAP_ERROR_RFMON_NOTSUP; |
| goto bad; |
| } |
| if (osinfo.release[0] == '8' && |
| osinfo.release[1] == '.') { |
| /* |
| * 10.4 (Darwin 8.x). s/en/wlt/ |
| */ |
| if (strncmp(p->opt.source, "en", 2) != 0) { |
| /* |
| * Not an enN device; check |
| * whether the device even exists. |
| */ |
| sockfd = socket(AF_INET, SOCK_DGRAM, 0); |
| if (sockfd != -1) { |
| strlcpy(ifrname, |
| p->opt.source, ifnamsiz); |
| if (ioctl(sockfd, SIOCGIFFLAGS, |
| (char *)&ifr) < 0) { |
| /* |
| * We assume this |
| * failed because |
| * the underlying |
| * device doesn't |
| * exist. |
| */ |
| status = PCAP_ERROR_NO_SUCH_DEVICE; |
| snprintf(p->errbuf, |
| PCAP_ERRBUF_SIZE, |
| "SIOCGIFFLAGS failed: %s", |
| pcap_strerror(errno)); |
| } else |
| status = PCAP_ERROR_RFMON_NOTSUP; |
| close(sockfd); |
| } else { |
| /* |
| * We can't find out whether |
| * the device exists, so just |
| * report "no such device". |
| */ |
| status = PCAP_ERROR_NO_SUCH_DEVICE; |
| snprintf(p->errbuf, |
| PCAP_ERRBUF_SIZE, |
| "socket() failed: %s", |
| pcap_strerror(errno)); |
| } |
| goto bad; |
| } |
| wltdev = malloc(strlen(p->opt.source) + 2); |
| if (wltdev == NULL) { |
| (void)snprintf(p->errbuf, |
| PCAP_ERRBUF_SIZE, "malloc: %s", |
| pcap_strerror(errno)); |
| status = PCAP_ERROR; |
| goto bad; |
| } |
| strcpy(wltdev, "wlt"); |
| strcat(wltdev, p->opt.source + 2); |
| free(p->opt.source); |
| p->opt.source = wltdev; |
| } |
| /* |
| * Everything else is 10.5 or later; for those, |
| * we just open the enN device, and set the DLT. |
| */ |
| } |
| } |
| #endif /* __APPLE__ */ |
| #ifdef HAVE_ZEROCOPY_BPF |
| /* |
| * If the BPF extension to set buffer mode is present, try setting |
| * the mode to zero-copy. If that fails, use regular buffering. If |
| * it succeeds but other setup fails, return an error to the user. |
| */ |
| bufmode = BPF_BUFMODE_ZBUF; |
| if (ioctl(fd, BIOCSETBUFMODE, (caddr_t)&bufmode) == 0) { |
| /* |
| * We have zerocopy BPF; use it. |
| */ |
| p->md.zerocopy = 1; |
| |
| /* |
| * How to pick a buffer size: first, query the maximum buffer |
| * size supported by zero-copy. This also lets us quickly |
| * determine whether the kernel generally supports zero-copy. |
| * Then, if a buffer size was specified, use that, otherwise |
| * query the default buffer size, which reflects kernel |
| * policy for a desired default. Round to the nearest page |
| * size. |
| */ |
| if (ioctl(fd, BIOCGETZMAX, (caddr_t)&zbufmax) < 0) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCGETZMAX: %s", |
| pcap_strerror(errno)); |
| goto bad; |
| } |
| |
| if (p->opt.buffer_size != 0) { |
| /* |
| * A buffer size was explicitly specified; use it. |
| */ |
| v = p->opt.buffer_size; |
| } else { |
| if ((ioctl(fd, BIOCGBLEN, (caddr_t)&v) < 0) || |
| v < DEFAULT_BUFSIZE) |
| v = DEFAULT_BUFSIZE; |
| } |
| #ifndef roundup |
| #define roundup(x, y) ((((x)+((y)-1))/(y))*(y)) /* to any y */ |
| #endif |
| p->md.zbufsize = roundup(v, getpagesize()); |
| if (p->md.zbufsize > zbufmax) |
| p->md.zbufsize = zbufmax; |
| p->md.zbuf1 = mmap(NULL, p->md.zbufsize, PROT_READ | PROT_WRITE, |
| MAP_ANON, -1, 0); |
| p->md.zbuf2 = mmap(NULL, p->md.zbufsize, PROT_READ | PROT_WRITE, |
| MAP_ANON, -1, 0); |
| if (p->md.zbuf1 == MAP_FAILED || p->md.zbuf2 == MAP_FAILED) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "mmap: %s", |
| pcap_strerror(errno)); |
| goto bad; |
| } |
| bzero(&bz, sizeof(bz)); |
| bz.bz_bufa = p->md.zbuf1; |
| bz.bz_bufb = p->md.zbuf2; |
| bz.bz_buflen = p->md.zbufsize; |
| if (ioctl(fd, BIOCSETZBUF, (caddr_t)&bz) < 0) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCSETZBUF: %s", |
| pcap_strerror(errno)); |
| goto bad; |
| } |
| (void)strncpy(ifrname, p->opt.source, ifnamsiz); |
| if (ioctl(fd, BIOCSETIF, (caddr_t)&ifr) < 0) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCSETIF: %s: %s", |
| p->opt.source, pcap_strerror(errno)); |
| goto bad; |
| } |
| v = p->md.zbufsize - sizeof(struct bpf_zbuf_header); |
| } else |
| #endif |
| { |
| /* |
| * We don't have zerocopy BPF. |
| * Set the buffer size. |
| */ |
| if (p->opt.buffer_size != 0) { |
| /* |
| * A buffer size was explicitly specified; use it. |
| */ |
| if (ioctl(fd, BIOCSBLEN, |
| (caddr_t)&p->opt.buffer_size) < 0) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "BIOCSBLEN: %s: %s", p->opt.source, |
| pcap_strerror(errno)); |
| status = PCAP_ERROR; |
| goto bad; |
| } |
| |
| /* |
| * Now bind to the device. |
| */ |
| (void)strncpy(ifrname, p->opt.source, ifnamsiz); |
| #ifdef BIOCSETLIF |
| if (ioctl(fd, BIOCSETLIF, (caddr_t)&ifr) < 0) |
| #else |
| if (ioctl(fd, BIOCSETIF, (caddr_t)&ifr) < 0) |
| #endif |
| { |
| status = check_setif_failure(p, errno); |
| goto bad; |
| } |
| } else { |
| /* |
| * No buffer size was explicitly specified. |
| * |
| * Try finding a good size for the buffer; |
| * DEFAULT_BUFSIZE may be too big, so keep |
| * cutting it in half until we find a size |
| * that works, or run out of sizes to try. |
| * If the default is larger, don't make it smaller. |
| */ |
| if ((ioctl(fd, BIOCGBLEN, (caddr_t)&v) < 0) || |
| v < DEFAULT_BUFSIZE) |
| v = DEFAULT_BUFSIZE; |
| for ( ; v != 0; v >>= 1) { |
| /* |
| * Ignore the return value - this is because the |
| * call fails on BPF systems that don't have |
| * kernel malloc. And if the call fails, it's |
| * no big deal, we just continue to use the |
| * standard buffer size. |
| */ |
| (void) ioctl(fd, BIOCSBLEN, (caddr_t)&v); |
| |
| (void)strncpy(ifrname, p->opt.source, ifnamsiz); |
| #ifdef BIOCSETLIF |
| if (ioctl(fd, BIOCSETLIF, (caddr_t)&ifr) >= 0) |
| #else |
| if (ioctl(fd, BIOCSETIF, (caddr_t)&ifr) >= 0) |
| #endif |
| break; /* that size worked; we're done */ |
| |
| if (errno != ENOBUFS) { |
| status = check_setif_failure(p, errno); |
| goto bad; |
| } |
| } |
| |
| if (v == 0) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "BIOCSBLEN: %s: No buffer size worked", |
| p->opt.source); |
| status = PCAP_ERROR; |
| goto bad; |
| } |
| } |
| } |
| |
| /* Get the data link layer type. */ |
| if (ioctl(fd, BIOCGDLT, (caddr_t)&v) < 0) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCGDLT: %s", |
| pcap_strerror(errno)); |
| status = PCAP_ERROR; |
| goto bad; |
| } |
| |
| #ifdef _AIX |
| /* |
| * AIX's BPF returns IFF_ types, not DLT_ types, in BIOCGDLT. |
| */ |
| switch (v) { |
| |
| case IFT_ETHER: |
| case IFT_ISO88023: |
| v = DLT_EN10MB; |
| break; |
| |
| case IFT_FDDI: |
| v = DLT_FDDI; |
| break; |
| |
| case IFT_ISO88025: |
| v = DLT_IEEE802; |
| break; |
| |
| case IFT_LOOP: |
| v = DLT_NULL; |
| break; |
| |
| default: |
| /* |
| * We don't know what to map this to yet. |
| */ |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "unknown interface type %u", |
| v); |
| status = PCAP_ERROR; |
| goto bad; |
| } |
| #endif |
| #if _BSDI_VERSION - 0 >= 199510 |
| /* The SLIP and PPP link layer header changed in BSD/OS 2.1 */ |
| switch (v) { |
| |
| case DLT_SLIP: |
| v = DLT_SLIP_BSDOS; |
| break; |
| |
| case DLT_PPP: |
| v = DLT_PPP_BSDOS; |
| break; |
| |
| case 11: /*DLT_FR*/ |
| v = DLT_FRELAY; |
| break; |
| |
| case 12: /*DLT_C_HDLC*/ |
| v = DLT_CHDLC; |
| break; |
| } |
| #endif |
| |
| #ifdef BIOCGDLTLIST |
| /* |
| * We know the default link type -- now determine all the DLTs |
| * this interface supports. If this fails with EINVAL, it's |
| * not fatal; we just don't get to use the feature later. |
| */ |
| if (get_dlt_list(fd, v, &bdl, p->errbuf) == -1) { |
| status = PCAP_ERROR; |
| goto bad; |
| } |
| p->dlt_count = bdl.bfl_len; |
| p->dlt_list = bdl.bfl_list; |
| |
| #ifdef __APPLE__ |
| /* |
| * Monitor mode fun, continued. |
| * |
| * For 10.5 and, we're assuming, later releases, as noted above, |
| * 802.1 adapters that support monitor mode offer both DLT_EN10MB, |
| * DLT_IEEE802_11, and possibly some 802.11-plus-radio-information |
| * DLT_ value. Choosing one of the 802.11 DLT_ values will turn |
| * monitor mode on. |
| * |
| * Therefore, if the user asked for monitor mode, we filter out |
| * the DLT_EN10MB value, as you can't get that in monitor mode, |
| * and, if the user didn't ask for monitor mode, we filter out |
| * the 802.11 DLT_ values, because selecting those will turn |
| * monitor mode on. Then, for monitor mode, if an 802.11-plus- |
| * radio DLT_ value is offered, we try to select that, otherwise |
| * we try to select DLT_IEEE802_11. |
| */ |
| if (have_osinfo) { |
| if (isdigit((unsigned)osinfo.release[0]) && |
| (osinfo.release[0] == '9' || |
| isdigit((unsigned)osinfo.release[1]))) { |
| /* |
| * 10.5 (Darwin 9.x), or later. |
| */ |
| new_dlt = find_802_11(&bdl); |
| if (new_dlt != -1) { |
| /* |
| * We have at least one 802.11 DLT_ value, |
| * so this is an 802.11 interface. |
| * new_dlt is the best of the 802.11 |
| * DLT_ values in the list. |
| */ |
| if (p->opt.rfmon) { |
| /* |
| * Our caller wants monitor mode. |
| * Purge DLT_EN10MB from the list |
| * of link-layer types, as selecting |
| * it will keep monitor mode off. |
| */ |
| remove_en(p); |
| |
| /* |
| * If the new mode we want isn't |
| * the default mode, attempt to |
| * select the new mode. |
| */ |
| if (new_dlt != v) { |
| if (ioctl(p->fd, BIOCSDLT, |
| &new_dlt) != -1) { |
| /* |
| * We succeeded; |
| * make this the |
| * new DLT_ value. |
| */ |
| v = new_dlt; |
| } |
| } |
| } else { |
| /* |
| * Our caller doesn't want |
| * monitor mode. Unless this |
| * is being done by pcap_open_live(), |
| * purge the 802.11 link-layer types |
| * from the list, as selecting |
| * one of them will turn monitor |
| * mode on. |
| */ |
| if (!p->oldstyle) |
| remove_802_11(p); |
| } |
| } else { |
| if (p->opt.rfmon) { |
| /* |
| * The caller requested monitor |
| * mode, but we have no 802.11 |
| * link-layer types, so they |
| * can't have it. |
| */ |
| status = PCAP_ERROR_RFMON_NOTSUP; |
| goto bad; |
| } |
| } |
| } |
| } |
| #elif defined(HAVE_BSD_IEEE80211) |
| /* |
| * *BSD with the new 802.11 ioctls. |
| * Do we want monitor mode? |
| */ |
| if (p->opt.rfmon) { |
| /* |
| * Try to put the interface into monitor mode. |
| */ |
| status = monitor_mode(p, 1); |
| if (status != 0) { |
| /* |
| * We failed. |
| */ |
| goto bad; |
| } |
| |
| /* |
| * We're in monitor mode. |
| * Try to find the best 802.11 DLT_ value and, if we |
| * succeed, try to switch to that mode if we're not |
| * already in that mode. |
| */ |
| new_dlt = find_802_11(&bdl); |
| if (new_dlt != -1) { |
| /* |
| * We have at least one 802.11 DLT_ value. |
| * new_dlt is the best of the 802.11 |
| * DLT_ values in the list. |
| * |
| * If the new mode we want isn't the default mode, |
| * attempt to select the new mode. |
| */ |
| if (new_dlt != v) { |
| if (ioctl(p->fd, BIOCSDLT, &new_dlt) != -1) { |
| /* |
| * We succeeded; make this the |
| * new DLT_ value. |
| */ |
| v = new_dlt; |
| } |
| } |
| } |
| } |
| #endif /* various platforms */ |
| #endif /* BIOCGDLTLIST */ |
| |
| /* |
| * If this is an Ethernet device, and we don't have a DLT_ list, |
| * give it a list with DLT_EN10MB and DLT_DOCSIS. (That'd give |
| * 802.11 interfaces DLT_DOCSIS, which isn't the right thing to |
| * do, but there's not much we can do about that without finding |
| * some other way of determining whether it's an Ethernet or 802.11 |
| * device.) |
| */ |
| if (v == DLT_EN10MB && p->dlt_count == 0) { |
| p->dlt_list = (u_int *) malloc(sizeof(u_int) * 2); |
| /* |
| * If that fails, just leave the list empty. |
| */ |
| if (p->dlt_list != NULL) { |
| p->dlt_list[0] = DLT_EN10MB; |
| p->dlt_list[1] = DLT_DOCSIS; |
| p->dlt_count = 2; |
| } |
| } |
| #ifdef PCAP_FDDIPAD |
| if (v == DLT_FDDI) |
| p->fddipad = PCAP_FDDIPAD; |
| else |
| p->fddipad = 0; |
| #endif |
| p->linktype = v; |
| |
| #if defined(BIOCGHDRCMPLT) && defined(BIOCSHDRCMPLT) |
| /* |
| * Do a BIOCSHDRCMPLT, if defined, to turn that flag on, so |
| * the link-layer source address isn't forcibly overwritten. |
| * (Should we ignore errors? Should we do this only if |
| * we're open for writing?) |
| * |
| * XXX - I seem to remember some packet-sending bug in some |
| * BSDs - check CVS log for "bpf.c"? |
| */ |
| if (ioctl(fd, BIOCSHDRCMPLT, &spoof_eth_src) == -1) { |
| (void)snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "BIOCSHDRCMPLT: %s", pcap_strerror(errno)); |
| status = PCAP_ERROR; |
| goto bad; |
| } |
| #endif |
| /* set timeout */ |
| #ifdef HAVE_ZEROCOPY_BPF |
| if (p->md.timeout != 0 && !p->md.zerocopy) { |
| #else |
| if (p->md.timeout) { |
| #endif |
| /* |
| * XXX - is this seconds/nanoseconds in AIX? |
| * (Treating it as such doesn't fix the timeout |
| * problem described below.) |
| * |
| * XXX - Mac OS X 10.6 mishandles BIOCSRTIMEOUT in |
| * 64-bit userland - it takes, as an argument, a |
| * "struct BPF_TIMEVAL", which has 32-bit tv_sec |
| * and tv_usec, rather than a "struct timeval". |
| * |
| * If this platform defines "struct BPF_TIMEVAL", |
| * we check whether the structure size in BIOCSRTIMEOUT |
| * is that of a "struct timeval" and, if not, we use |
| * a "struct BPF_TIMEVAL" rather than a "struct timeval". |
| * (That way, if the bug is fixed in a future release, |
| * we will still do the right thing.) |
| */ |
| struct timeval to; |
| #ifdef HAVE_STRUCT_BPF_TIMEVAL |
| struct BPF_TIMEVAL bpf_to; |
| |
| if (IOCPARM_LEN(BIOCSRTIMEOUT) != sizeof(struct timeval)) { |
| bpf_to.tv_sec = p->md.timeout / 1000; |
| bpf_to.tv_usec = (p->md.timeout * 1000) % 1000000; |
| if (ioctl(p->fd, BIOCSRTIMEOUT, (caddr_t)&bpf_to) < 0) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "BIOCSRTIMEOUT: %s", pcap_strerror(errno)); |
| status = PCAP_ERROR; |
| goto bad; |
| } |
| } else { |
| #endif |
| to.tv_sec = p->md.timeout / 1000; |
| to.tv_usec = (p->md.timeout * 1000) % 1000000; |
| if (ioctl(p->fd, BIOCSRTIMEOUT, (caddr_t)&to) < 0) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "BIOCSRTIMEOUT: %s", pcap_strerror(errno)); |
| status = PCAP_ERROR; |
| goto bad; |
| } |
| #ifdef HAVE_STRUCT_BPF_TIMEVAL |
| } |
| #endif |
| } |
| |
| #ifdef _AIX |
| #ifdef BIOCIMMEDIATE |
| /* |
| * Darren Reed notes that |
| * |
| * On AIX (4.2 at least), if BIOCIMMEDIATE is not set, the |
| * timeout appears to be ignored and it waits until the buffer |
| * is filled before returning. The result of not having it |
| * set is almost worse than useless if your BPF filter |
| * is reducing things to only a few packets (i.e. one every |
| * second or so). |
| * |
| * so we turn BIOCIMMEDIATE mode on if this is AIX. |
| * |
| * We don't turn it on for other platforms, as that means we |
| * get woken up for every packet, which may not be what we want; |
| * in the Winter 1993 USENIX paper on BPF, they say: |
| * |
| * Since a process might want to look at every packet on a |
| * network and the time between packets can be only a few |
| * microseconds, it is not possible to do a read system call |
| * per packet and BPF must collect the data from several |
| * packets and return it as a unit when the monitoring |
| * application does a read. |
| * |
| * which I infer is the reason for the timeout - it means we |
| * wait that amount of time, in the hopes that more packets |
| * will arrive and we'll get them all with one read. |
| * |
| * Setting BIOCIMMEDIATE mode on FreeBSD (and probably other |
| * BSDs) causes the timeout to be ignored. |
| * |
| * On the other hand, some platforms (e.g., Linux) don't support |
| * timeouts, they just hand stuff to you as soon as it arrives; |
| * if that doesn't cause a problem on those platforms, it may |
| * be OK to have BIOCIMMEDIATE mode on BSD as well. |
| * |
| * (Note, though, that applications may depend on the read |
| * completing, even if no packets have arrived, when the timeout |
| * expires, e.g. GUI applications that have to check for input |
| * while waiting for packets to arrive; a non-zero timeout |
| * prevents "select()" from working right on FreeBSD and |
| * possibly other BSDs, as the timer doesn't start until a |
| * "read()" is done, so the timer isn't in effect if the |
| * application is blocked on a "select()", and the "select()" |
| * doesn't get woken up for a BPF device until the buffer |
| * fills up.) |
| */ |
| v = 1; |
| if (ioctl(p->fd, BIOCIMMEDIATE, &v) < 0) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCIMMEDIATE: %s", |
| pcap_strerror(errno)); |
| status = PCAP_ERROR; |
| goto bad; |
| } |
| #endif /* BIOCIMMEDIATE */ |
| #endif /* _AIX */ |
| |
| if (p->opt.promisc) { |
| /* set promiscuous mode, just warn if it fails */ |
| if (ioctl(p->fd, BIOCPROMISC, NULL) < 0) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCPROMISC: %s", |
| pcap_strerror(errno)); |
| status = PCAP_WARNING_PROMISC_NOTSUP; |
| } |
| } |
| |
| if (ioctl(fd, BIOCGBLEN, (caddr_t)&v) < 0) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCGBLEN: %s", |
| pcap_strerror(errno)); |
| status = PCAP_ERROR; |
| goto bad; |
| } |
| p->bufsize = v; |
| #ifdef HAVE_ZEROCOPY_BPF |
| if (!p->md.zerocopy) { |
| #endif |
| p->buffer = (u_char *)malloc(p->bufsize); |
| if (p->buffer == NULL) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", |
| pcap_strerror(errno)); |
| status = PCAP_ERROR; |
| goto bad; |
| } |
| #ifdef _AIX |
| /* For some strange reason this seems to prevent the EFAULT |
| * problems we have experienced from AIX BPF. */ |
| memset(p->buffer, 0x0, p->bufsize); |
| #endif |
| #ifdef HAVE_ZEROCOPY_BPF |
| } |
| #endif |
| |
| /* |
| * If there's no filter program installed, there's |
| * no indication to the kernel of what the snapshot |
| * length should be, so no snapshotting is done. |
| * |
| * Therefore, when we open the device, we install |
| * an "accept everything" filter with the specified |
| * snapshot length. |
| */ |
| total_insn.code = (u_short)(BPF_RET | BPF_K); |
| total_insn.jt = 0; |
| total_insn.jf = 0; |
| total_insn.k = p->snapshot; |
| |
| total_prog.bf_len = 1; |
| total_prog.bf_insns = &total_insn; |
| if (ioctl(p->fd, BIOCSETF, (caddr_t)&total_prog) < 0) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCSETF: %s", |
| pcap_strerror(errno)); |
| status = PCAP_ERROR; |
| goto bad; |
| } |
| |
| /* |
| * On most BPF platforms, either you can do a "select()" or |
| * "poll()" on a BPF file descriptor and it works correctly, |
| * or you can do it and it will return "readable" if the |
| * hold buffer is full but not if the timeout expires *and* |
| * a non-blocking read will, if the hold buffer is empty |
| * but the store buffer isn't empty, rotate the buffers |
| * and return what packets are available. |
| * |
| * In the latter case, the fact that a non-blocking read |
| * will give you the available packets means you can work |
| * around the failure of "select()" and "poll()" to wake up |
| * and return "readable" when the timeout expires by using |
| * the timeout as the "select()" or "poll()" timeout, putting |
| * the BPF descriptor into non-blocking mode, and read from |
| * it regardless of whether "select()" reports it as readable |
| * or not. |
| * |
| * However, in FreeBSD 4.3 and 4.4, "select()" and "poll()" |
| * won't wake up and return "readable" if the timer expires |
| * and non-blocking reads return EWOULDBLOCK if the hold |
| * buffer is empty, even if the store buffer is non-empty. |
| * |
| * This means the workaround in question won't work. |
| * |
| * Therefore, on FreeBSD 4.3 and 4.4, we set "p->selectable_fd" |
| * to -1, which means "sorry, you can't use 'select()' or 'poll()' |
| * here". On all other BPF platforms, we set it to the FD for |
| * the BPF device; in NetBSD, OpenBSD, and Darwin, a non-blocking |
| * read will, if the hold buffer is empty and the store buffer |
| * isn't empty, rotate the buffers and return what packets are |
| * there (and in sufficiently recent versions of OpenBSD |
| * "select()" and "poll()" should work correctly). |
| * |
| * XXX - what about AIX? |
| */ |
| p->selectable_fd = p->fd; /* assume select() works until we know otherwise */ |
| if (have_osinfo) { |
| /* |
| * We can check what OS this is. |
| */ |
| if (strcmp(osinfo.sysname, "FreeBSD") == 0) { |
| if (strncmp(osinfo.release, "4.3-", 4) == 0 || |
| strncmp(osinfo.release, "4.4-", 4) == 0) |
| p->selectable_fd = -1; |
| } |
| } |
| |
| p->read_op = pcap_read_bpf; |
| p->inject_op = pcap_inject_bpf; |
| p->setfilter_op = pcap_setfilter_bpf; |
| p->setdirection_op = pcap_setdirection_bpf; |
| p->set_datalink_op = pcap_set_datalink_bpf; |
| p->getnonblock_op = pcap_getnonblock_bpf; |
| p->setnonblock_op = pcap_setnonblock_bpf; |
| p->stats_op = pcap_stats_bpf; |
| p->cleanup_op = pcap_cleanup_bpf; |
| |
| return (status); |
| bad: |
| pcap_cleanup_bpf(p); |
| return (status); |
| } |
| |
| int |
| pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf) |
| { |
| #ifdef HAVE_DAG_API |
| if (dag_platform_finddevs(alldevsp, errbuf) < 0) |
| return (-1); |
| #endif /* HAVE_DAG_API */ |
| #ifdef HAVE_SNF_API |
| if (snf_platform_finddevs(alldevsp, errbuf) < 0) |
| return (-1); |
| #endif /* HAVE_SNF_API */ |
| |
| return (0); |
| } |
| |
| #ifdef HAVE_BSD_IEEE80211 |
| static int |
| monitor_mode(pcap_t *p, int set) |
| { |
| int sock; |
| struct ifmediareq req; |
| int *media_list; |
| int i; |
| int can_do; |
| struct ifreq ifr; |
| |
| sock = socket(AF_INET, SOCK_DGRAM, 0); |
| if (sock == -1) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "can't open socket: %s", |
| pcap_strerror(errno)); |
| return (PCAP_ERROR); |
| } |
| |
| memset(&req, 0, sizeof req); |
| strncpy(req.ifm_name, p->opt.source, sizeof req.ifm_name); |
| |
| /* |
| * Find out how many media types we have. |
| */ |
| if (ioctl(sock, SIOCGIFMEDIA, &req) < 0) { |
| /* |
| * Can't get the media types. |
| */ |
| switch (errno) { |
| |
| case ENXIO: |
| /* |
| * There's no such device. |
| */ |
| close(sock); |
| return (PCAP_ERROR_NO_SUCH_DEVICE); |
| |
| case EINVAL: |
| /* |
| * Interface doesn't support SIOC{G,S}IFMEDIA. |
| */ |
| close(sock); |
| return (PCAP_ERROR_RFMON_NOTSUP); |
| |
| default: |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "SIOCGIFMEDIA 1: %s", pcap_strerror(errno)); |
| close(sock); |
| return (PCAP_ERROR); |
| } |
| } |
| if (req.ifm_count == 0) { |
| /* |
| * No media types. |
| */ |
| close(sock); |
| return (PCAP_ERROR_RFMON_NOTSUP); |
| } |
| |
| /* |
| * Allocate a buffer to hold all the media types, and |
| * get the media types. |
| */ |
| media_list = malloc(req.ifm_count * sizeof(int)); |
| if (media_list == NULL) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", |
| pcap_strerror(errno)); |
| close(sock); |
| return (PCAP_ERROR); |
| } |
| req.ifm_ulist = media_list; |
| if (ioctl(sock, SIOCGIFMEDIA, &req) < 0) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "SIOCGIFMEDIA: %s", |
| pcap_strerror(errno)); |
| free(media_list); |
| close(sock); |
| return (PCAP_ERROR); |
| } |
| |
| /* |
| * Look for an 802.11 "automatic" media type. |
| * We assume that all 802.11 adapters have that media type, |
| * and that it will carry the monitor mode supported flag. |
| */ |
| can_do = 0; |
| for (i = 0; i < req.ifm_count; i++) { |
| if (IFM_TYPE(media_list[i]) == IFM_IEEE80211 |
| && IFM_SUBTYPE(media_list[i]) == IFM_AUTO) { |
| /* OK, does it do monitor mode? */ |
| if (media_list[i] & IFM_IEEE80211_MONITOR) { |
| can_do = 1; |
| break; |
| } |
| } |
| } |
| free(media_list); |
| if (!can_do) { |
| /* |
| * This adapter doesn't support monitor mode. |
| */ |
| close(sock); |
| return (PCAP_ERROR_RFMON_NOTSUP); |
| } |
| |
| if (set) { |
| /* |
| * Don't just check whether we can enable monitor mode, |
| * do so, if it's not already enabled. |
| */ |
| if ((req.ifm_current & IFM_IEEE80211_MONITOR) == 0) { |
| /* |
| * Monitor mode isn't currently on, so turn it on, |
| * and remember that we should turn it off when the |
| * pcap_t is closed. |
| */ |
| |
| /* |
| * If we haven't already done so, arrange to have |
| * "pcap_close_all()" called when we exit. |
| */ |
| if (!pcap_do_addexit(p)) { |
| /* |
| * "atexit()" failed; don't put the interface |
| * in monitor mode, just give up. |
| */ |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "atexit failed"); |
| close(sock); |
| return (PCAP_ERROR); |
| } |
| memset(&ifr, 0, sizeof(ifr)); |
| (void)strncpy(ifr.ifr_name, p->opt.source, |
| sizeof(ifr.ifr_name)); |
| ifr.ifr_media = req.ifm_current | IFM_IEEE80211_MONITOR; |
| if (ioctl(sock, SIOCSIFMEDIA, &ifr) == -1) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| "SIOCSIFMEDIA: %s", pcap_strerror(errno)); |
| close(sock); |
| return (PCAP_ERROR); |
| } |
| |
| p->md.must_do_on_close |= MUST_CLEAR_RFMON; |
| |
| /* |
| * Add this to the list of pcaps to close when we exit. |
| */ |
| pcap_add_to_pcaps_to_close(p); |
| } |
| } |
| return (0); |
| } |
| #endif /* HAVE_BSD_IEEE80211 */ |
| |
| #if defined(BIOCGDLTLIST) && (defined(__APPLE__) || defined(HAVE_BSD_IEEE80211)) |
| /* |
| * Check whether we have any 802.11 link-layer types; return the best |
| * of the 802.11 link-layer types if we find one, and return -1 |
| * otherwise. |
| * |
| * DLT_IEEE802_11_RADIO, with the radiotap header, is considered the |
| * best 802.11 link-layer type; any of the other 802.11-plus-radio |
| * headers are second-best; 802.11 with no radio information is |
| * the least good. |
| */ |
| static int |
| find_802_11(struct bpf_dltlist *bdlp) |
| { |
| int new_dlt; |
| int i; |
| |
| /* |
| * Scan the list of DLT_ values, looking for 802.11 values, |
| * and, if we find any, choose the best of them. |
| */ |
| new_dlt = -1; |
| for (i = 0; i < bdlp->bfl_len; i++) { |
| switch (bdlp->bfl_list[i]) { |
| |
| case DLT_IEEE802_11: |
| /* |
| * 802.11, but no radio. |
| * |
| * Offer this, and select it as the new mode |
| * unless we've already found an 802.11 |
| * header with radio information. |
| */ |
| if (new_dlt == -1) |
| new_dlt = bdlp->bfl_list[i]; |
| break; |
| |
| case DLT_PRISM_HEADER: |
| case DLT_AIRONET_HEADER: |
| case DLT_IEEE802_11_RADIO_AVS: |
| /* |
| * 802.11 with radio, but not radiotap. |
| * |
| * Offer this, and select it as the new mode |
| * unless we've already found the radiotap DLT_. |
| */ |
| if (new_dlt != DLT_IEEE802_11_RADIO) |
| new_dlt = bdlp->bfl_list[i]; |
| break; |
| |
| case DLT_IEEE802_11_RADIO: |
| /* |
| * 802.11 with radiotap. |
| * |
| * Offer this, and select it as the new mode. |
| */ |
| new_dlt = bdlp->bfl_list[i]; |
| break; |
| |
| default: |
| /* |
| * Not 802.11. |
| */ |
| break; |
| } |
| } |
| |
| return (new_dlt); |
| } |
| #endif /* defined(BIOCGDLTLIST) && (defined(__APPLE__) || defined(HAVE_BSD_IEEE80211)) */ |
| |
| #if defined(__APPLE__) && defined(BIOCGDLTLIST) |
| /* |
| * Remove DLT_EN10MB from the list of DLT_ values, as we're in monitor mode, |
| * and DLT_EN10MB isn't supported in monitor mode. |
| */ |
| static void |
| remove_en(pcap_t *p) |
| { |
| int i, j; |
| |
| /* |
| * Scan the list of DLT_ values and discard DLT_EN10MB. |
| */ |
| j = 0; |
| for (i = 0; i < p->dlt_count; i++) { |
| switch (p->dlt_list[i]) { |
| |
| case DLT_EN10MB: |
| /* |
| * Don't offer this one. |
| */ |
| continue; |
| |
| default: |
| /* |
| * Just copy this mode over. |
| */ |
| break; |
| } |
| |
| /* |
| * Copy this DLT_ value to its new position. |
| */ |
| p->dlt_list[j] = p->dlt_list[i]; |
| j++; |
| } |
| |
| /* |
| * Set the DLT_ count to the number of entries we copied. |
| */ |
| p->dlt_count = j; |
| } |
| |
| /* |
| * Remove 802.11 link-layer types from the list of DLT_ values, as |
| * we're not in monitor mode, and those DLT_ values will switch us |
| * to monitor mode. |
| */ |
| static void |
| remove_802_11(pcap_t *p) |
| { |
| int i, j; |
| |
| /* |
| * Scan the list of DLT_ values and discard 802.11 values. |
| */ |
| j = 0; |
| for (i = 0; i < p->dlt_count; i++) { |
| switch (p->dlt_list[i]) { |
| |
| case DLT_IEEE802_11: |
| case DLT_PRISM_HEADER: |
| case DLT_AIRONET_HEADER: |
| case DLT_IEEE802_11_RADIO: |
| case DLT_IEEE802_11_RADIO_AVS: |
| /* |
| * 802.11. Don't offer this one. |
| */ |
| continue; |
| |
| default: |
| /* |
| * Just copy this mode over. |
| */ |
| break; |
| } |
| |
| /* |
| * Copy this DLT_ value to its new position. |
| */ |
| p->dlt_list[j] = p->dlt_list[i]; |
| j++; |
| } |
| |
| /* |
| * Set the DLT_ count to the number of entries we copied. |
| */ |
| p->dlt_count = j; |
| } |
| #endif /* defined(__APPLE__) && defined(BIOCGDLTLIST) */ |
| |
| static int |
| pcap_setfilter_bpf(pcap_t *p, struct bpf_program *fp) |
| { |
| /* |
| * Free any user-mode filter we might happen to have installed. |
| */ |
| pcap_freecode(&p->fcode); |
| |
| /* |
| * Try to install the kernel filter. |
| */ |
| if (ioctl(p->fd, BIOCSETF, (caddr_t)fp) == 0) { |
| /* |
| * It worked. |
| */ |
| p->md.use_bpf = 1; /* filtering in the kernel */ |
| |
| /* |
| * Discard any previously-received packets, as they might |
| * have passed whatever filter was formerly in effect, but |
| * might not pass this filter (BIOCSETF discards packets |
| * buffered in the kernel, so you can lose packets in any |
| * case). |
| */ |
| p->cc = 0; |
| return (0); |
| } |
| |
| /* |
| * We failed. |
| * |
| * If it failed with EINVAL, that's probably because the program |
| * is invalid or too big. Validate it ourselves; if we like it |
| * (we currently allow backward branches, to support protochain), |
| * run it in userland. (There's no notion of "too big" for |
| * userland.) |
| * |
| * Otherwise, just give up. |
| * XXX - if the copy of the program into the kernel failed, |
| * we will get EINVAL rather than, say, EFAULT on at least |
| * some kernels. |
| */ |
| if (errno != EINVAL) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCSETF: %s", |
| pcap_strerror(errno)); |
| return (-1); |
| } |
| |
| /* |
| * install_bpf_program() validates the program. |
| * |
| * XXX - what if we already have a filter in the kernel? |
| */ |
| if (install_bpf_program(p, fp) < 0) |
| return (-1); |
| p->md.use_bpf = 0; /* filtering in userland */ |
| return (0); |
| } |
| |
| /* |
| * Set direction flag: Which packets do we accept on a forwarding |
| * single device? IN, OUT or both? |
| */ |
| static int |
| pcap_setdirection_bpf(pcap_t *p, pcap_direction_t d) |
| { |
| #if defined(BIOCSDIRECTION) |
| u_int direction; |
| |
| direction = (d == PCAP_D_IN) ? BPF_D_IN : |
| ((d == PCAP_D_OUT) ? BPF_D_OUT : BPF_D_INOUT); |
| if (ioctl(p->fd, BIOCSDIRECTION, &direction) == -1) { |
| (void) snprintf(p->errbuf, sizeof(p->errbuf), |
| "Cannot set direction to %s: %s", |
| (d == PCAP_D_IN) ? "PCAP_D_IN" : |
| ((d == PCAP_D_OUT) ? "PCAP_D_OUT" : "PCAP_D_INOUT"), |
| strerror(errno)); |
| return (-1); |
| } |
| return (0); |
| #elif defined(BIOCSSEESENT) |
| u_int seesent; |
| |
| /* |
| * We don't support PCAP_D_OUT. |
| */ |
| if (d == PCAP_D_OUT) { |
| snprintf(p->errbuf, sizeof(p->errbuf), |
| "Setting direction to PCAP_D_OUT is not supported on BPF"); |
| return -1; |
| } |
| |
| seesent = (d == PCAP_D_INOUT); |
| if (ioctl(p->fd, BIOCSSEESENT, &seesent) == -1) { |
| (void) snprintf(p->errbuf, sizeof(p->errbuf), |
| "Cannot set direction to %s: %s", |
| (d == PCAP_D_INOUT) ? "PCAP_D_INOUT" : "PCAP_D_IN", |
| strerror(errno)); |
| return (-1); |
| } |
| return (0); |
| #else |
| (void) snprintf(p->errbuf, sizeof(p->errbuf), |
| "This system doesn't support BIOCSSEESENT, so the direction can't be set"); |
| return (-1); |
| #endif |
| } |
| |
| static int |
| pcap_set_datalink_bpf(pcap_t *p, int dlt) |
| { |
| #ifdef BIOCSDLT |
| if (ioctl(p->fd, BIOCSDLT, &dlt) == -1) { |
| (void) snprintf(p->errbuf, sizeof(p->errbuf), |
| "Cannot set DLT %d: %s", dlt, strerror(errno)); |
| return (-1); |
| } |
| #endif |
| return (0); |
| } |