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authorGuy Harris <gharris@steve.local>2009-06-01 13:03:05 -0700
committerGuy Harris <gharris@steve.local>2009-06-01 13:03:05 -0700
commit9a4ef64d7627242371a17bd7fe96ae9725f3ab62 (patch)
tree5b748f7759d7fbb96a81347b8e42487b0da176b2 /pcap-linux.c
parent102c1ff4609dbd83066f4e2257307004609403b9 (diff)
Move up the definition of get_mac80211_phydev() before all its uses.
Diffstat (limited to 'pcap-linux.c')
-rw-r--r--pcap-linux.c402
1 files changed, 201 insertions, 201 deletions
diff --git a/pcap-linux.c b/pcap-linux.c
index 8e484be..455077b 100644
--- a/pcap-linux.c
+++ b/pcap-linux.c
@@ -382,6 +382,207 @@ pcap_create(const char *device, char *ebuf)
return handle;
}
+#ifdef HAVE_LIBNL
+/*
+ *
+ * If interface {if} is a mac80211 driver, the file
+ * /sys/class/net/{if}/phy80211 is a symlink to
+ * /sys/class/ieee80211/{phydev}, for some {phydev}.
+ *
+ * On Fedora 9, with a 2.6.26.3-29 kernel, my Zydas stick, at
+ * least, has a "wmaster0" device and a "wlan0" device; the
+ * latter is the one with the IP address. Both show up in
+ * "tcpdump -D" output. Capturing on the wmaster0 device
+ * captures with 802.11 headers.
+ *
+ * airmon-ng searches through /sys/class/net for devices named
+ * monN, starting with mon0; as soon as one *doesn't* exist,
+ * it chooses that as the monitor device name. If the "iw"
+ * command exists, it does "iw dev {if} interface add {monif}
+ * type monitor", where {monif} is the monitor device. It
+ * then (sigh) sleeps .1 second, and then configures the
+ * device up. Otherwise, if /sys/class/ieee80211/{phydev}/add_iface
+ * is a file, it writes {mondev}, without a newline, to that file,
+ * and again (sigh) sleeps .1 second, and then iwconfig's that
+ * device into monitor mode and configures it up. Otherwise,
+ * you can't do monitor mode.
+ *
+ * All these devices are "glued" together by having the
+ * /sys/class/net/{device}/phy80211 links pointing to the same
+ * place, so, given a wmaster, wlan, or mon device, you can
+ * find the other devices by looking for devices with
+ * the same phy80211 link.
+ *
+ * To turn monitor mode off, delete the monitor interface,
+ * either with "iw dev {monif} interface del" or by sending
+ * {monif}, with no NL, down /sys/class/ieee80211/{phydev}/remove_iface
+ *
+ * Note: if you try to create a monitor device named "monN", and
+ * there's already a "monN" device, it fails, as least with
+ * the netlink interface (which is what iw uses), with a return
+ * value of -ENFILE. (Return values are negative errnos.) We
+ * could probably use that to find an unused device.
+ *
+ * Yes, you can have multiple monitor devices for a given
+ * physical device.
+*/
+
+/*
+ * Is this a mac80211 device? If so, fill in the physical device path and
+ * return 1; if not, return 0. On an error, fill in handle->errbuf and
+ * return PCAP_ERROR.
+ */
+static int
+get_mac80211_phydev(pcap_t *handle, const char *device, char *phydev_path,
+ size_t phydev_max_pathlen)
+{
+ char *pathstr;
+ ssize_t bytes_read;
+
+ /*
+ * Generate the path string for the symlink to the physical device.
+ */
+ if (asprintf(&pathstr, "/sys/class/net/%s/phy80211", device) == -1) {
+ snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
+ "%s: Can't generate path name string for /sys/class/net device",
+ device);
+ return PCAP_ERROR;
+ }
+ bytes_read = readlink(pathstr, phydev_path, phydev_max_pathlen);
+ if (bytes_read == -1) {
+ if (errno == ENOENT || errno == EINVAL) {
+ /*
+ * Doesn't exist, or not a symlink; assume that
+ * means it's not a mac80211 device.
+ */
+ free(pathstr);
+ return 0;
+ }
+ snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
+ "%s: Can't readlink %s: %s", device, pathstr,
+ strerror(errno));
+ free(pathstr);
+ return PCAP_ERROR;
+ }
+ free(pathstr);
+ phydev_path[bytes_read] = '\0';
+ return 1;
+}
+
+static int
+enter_rfmon_mode_mac80211(pcap_t *handle, int sock_fd, const char *device)
+{
+ int ret;
+ char phydev_path[PATH_MAX+1];
+ struct nl80211_state nlstate;
+ struct ifreq ifr;
+ u_int n;
+
+ /*
+ * Is this a mac80211 device?
+ */
+ ret = get_mac80211_phydev(handle, device, phydev_path, PATH_MAX);
+ if (ret < 0)
+ return ret; /* error */
+ if (ret == 0)
+ return 0; /* no error, but not mac80211 device */
+
+ /*
+ * XXX - is this already a monN device?
+ * If so, we're done.
+ * Is that determined by old Wireless Extensions ioctls?
+ */
+
+ /*
+ * OK, it's apparently a mac80211 device.
+ * Try to find an unused monN device for it.
+ */
+ ret = nl80211_init(handle, &nlstate, device);
+ if (ret != 0)
+ return ret;
+ for (n = 0; n < UINT_MAX; n++) {
+ /*
+ * Try mon{n}.
+ */
+ char mondevice[3+10+1]; /* mon{UINT_MAX}\0 */
+
+ snprintf(mondevice, sizeof mondevice, "mon%u", n);
+ ret = add_mon_if(handle, sock_fd, &nlstate, device, mondevice);
+ if (ret == 1) {
+ handle->md.mondevice = strdup(mondevice);
+ goto added;
+ }
+ if (ret < 0) {
+ /*
+ * Hard failure. Just return ret; handle->errbuf
+ * has already been set.
+ */
+ nl80211_cleanup(&nlstate);
+ return ret;
+ }
+ }
+
+ snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
+ "%s: No free monN interfaces", device);
+ nl80211_cleanup(&nlstate);
+ return PCAP_ERROR;
+
+added:
+
+#if 0
+ /*
+ * Sleep for .1 seconds.
+ */
+ delay.tv_sec = 0;
+ delay.tv_nsec = 500000000;
+ nanosleep(&delay, NULL);
+#endif
+
+ /*
+ * Now configure the monitor interface up.
+ */
+ memset(&ifr, 0, sizeof(ifr));
+ strncpy(ifr.ifr_name, handle->md.mondevice, sizeof(ifr.ifr_name));
+ if (ioctl(sock_fd, SIOCGIFFLAGS, &ifr) == -1) {
+ snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
+ "%s: Can't get flags for %s: %s", device,
+ handle->md.mondevice, strerror(errno));
+ del_mon_if(handle, sock_fd, &nlstate, device,
+ handle->md.mondevice);
+ nl80211_cleanup(&nlstate);
+ return PCAP_ERROR;
+ }
+ ifr.ifr_flags |= IFF_UP|IFF_RUNNING;
+ if (ioctl(sock_fd, SIOCSIFFLAGS, &ifr) == -1) {
+ snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
+ "%s: Can't set flags for %s: %s", device,
+ handle->md.mondevice, strerror(errno));
+ del_mon_if(handle, sock_fd, &nlstate, device,
+ handle->md.mondevice);
+ nl80211_cleanup(&nlstate);
+ return PCAP_ERROR;
+ }
+
+ /*
+ * Success. Clean up the libnl state.
+ */
+ nl80211_cleanup(&nlstate);
+
+ /*
+ * Note that we have to delete the monitor device when we close
+ * the handle.
+ */
+ handle->md.must_do_on_close |= MUST_DELETE_MONIF;
+
+ /*
+ * Add this to the list of pcaps to close when we exit.
+ */
+ pcap_add_to_pcaps_to_close(handle);
+
+ return 1;
+}
+#endif /* HAVE_LIBNL */
+
static int
pcap_can_set_rfmon_linux(pcap_t *handle)
{
@@ -2930,207 +3131,6 @@ iface_bind(int fd, int ifindex, char *ebuf)
return 1;
}
-#ifdef HAVE_LIBNL
-/*
- *
- * If interface {if} is a mac80211 driver, the file
- * /sys/class/net/{if}/phy80211 is a symlink to
- * /sys/class/ieee80211/{phydev}, for some {phydev}.
- *
- * On Fedora 9, with a 2.6.26.3-29 kernel, my Zydas stick, at
- * least, has a "wmaster0" device and a "wlan0" device; the
- * latter is the one with the IP address. Both show up in
- * "tcpdump -D" output. Capturing on the wmaster0 device
- * captures with 802.11 headers.
- *
- * airmon-ng searches through /sys/class/net for devices named
- * monN, starting with mon0; as soon as one *doesn't* exist,
- * it chooses that as the monitor device name. If the "iw"
- * command exists, it does "iw dev {if} interface add {monif}
- * type monitor", where {monif} is the monitor device. It
- * then (sigh) sleeps .1 second, and then configures the
- * device up. Otherwise, if /sys/class/ieee80211/{phydev}/add_iface
- * is a file, it writes {mondev}, without a newline, to that file,
- * and again (sigh) sleeps .1 second, and then iwconfig's that
- * device into monitor mode and configures it up. Otherwise,
- * you can't do monitor mode.
- *
- * All these devices are "glued" together by having the
- * /sys/class/net/{device}/phy80211 links pointing to the same
- * place, so, given a wmaster, wlan, or mon device, you can
- * find the other devices by looking for devices with
- * the same phy80211 link.
- *
- * To turn monitor mode off, delete the monitor interface,
- * either with "iw dev {monif} interface del" or by sending
- * {monif}, with no NL, down /sys/class/ieee80211/{phydev}/remove_iface
- *
- * Note: if you try to create a monitor device named "monN", and
- * there's already a "monN" device, it fails, as least with
- * the netlink interface (which is what iw uses), with a return
- * value of -ENFILE. (Return values are negative errnos.) We
- * could probably use that to find an unused device.
- *
- * Yes, you can have multiple monitor devices for a given
- * physical device.
-*/
-
-/*
- * Is this a mac80211 device? If so, fill in the physical device path and
- * return 1; if not, return 0. On an error, fill in handle->errbuf and
- * return PCAP_ERROR.
- */
-static int
-get_mac80211_phydev(pcap_t *handle, const char *device, char *phydev_path,
- size_t phydev_max_pathlen)
-{
- char *pathstr;
- ssize_t bytes_read;
-
- /*
- * Generate the path string for the symlink to the physical device.
- */
- if (asprintf(&pathstr, "/sys/class/net/%s/phy80211", device) == -1) {
- snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
- "%s: Can't generate path name string for /sys/class/net device",
- device);
- return PCAP_ERROR;
- }
- bytes_read = readlink(pathstr, phydev_path, phydev_max_pathlen);
- if (bytes_read == -1) {
- if (errno == ENOENT || errno == EINVAL) {
- /*
- * Doesn't exist, or not a symlink; assume that
- * means it's not a mac80211 device.
- */
- free(pathstr);
- return 0;
- }
- snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
- "%s: Can't readlink %s: %s", device, pathstr,
- strerror(errno));
- free(pathstr);
- return PCAP_ERROR;
- }
- free(pathstr);
- phydev_path[bytes_read] = '\0';
- return 1;
-}
-
-static int
-enter_rfmon_mode_mac80211(pcap_t *handle, int sock_fd, const char *device)
-{
- int ret;
- char phydev_path[PATH_MAX+1];
- struct nl80211_state nlstate;
- struct ifreq ifr;
- u_int n;
-
- /*
- * Is this a mac80211 device?
- */
- ret = get_mac80211_phydev(handle, device, phydev_path, PATH_MAX);
- if (ret < 0)
- return ret; /* error */
- if (ret == 0)
- return 0; /* no error, but not mac80211 device */
-
- /*
- * XXX - is this already a monN device?
- * If so, we're done.
- * Is that determined by old Wireless Extensions ioctls?
- */
-
- /*
- * OK, it's apparently a mac80211 device.
- * Try to find an unused monN device for it.
- */
- ret = nl80211_init(handle, &nlstate, device);
- if (ret != 0)
- return ret;
- for (n = 0; n < UINT_MAX; n++) {
- /*
- * Try mon{n}.
- */
- char mondevice[3+10+1]; /* mon{UINT_MAX}\0 */
-
- snprintf(mondevice, sizeof mondevice, "mon%u", n);
- ret = add_mon_if(handle, sock_fd, &nlstate, device, mondevice);
- if (ret == 1) {
- handle->md.mondevice = strdup(mondevice);
- goto added;
- }
- if (ret < 0) {
- /*
- * Hard failure. Just return ret; handle->errbuf
- * has already been set.
- */
- nl80211_cleanup(&nlstate);
- return ret;
- }
- }
-
- snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
- "%s: No free monN interfaces", device);
- nl80211_cleanup(&nlstate);
- return PCAP_ERROR;
-
-added:
-
-#if 0
- /*
- * Sleep for .1 seconds.
- */
- delay.tv_sec = 0;
- delay.tv_nsec = 500000000;
- nanosleep(&delay, NULL);
-#endif
-
- /*
- * Now configure the monitor interface up.
- */
- memset(&ifr, 0, sizeof(ifr));
- strncpy(ifr.ifr_name, handle->md.mondevice, sizeof(ifr.ifr_name));
- if (ioctl(sock_fd, SIOCGIFFLAGS, &ifr) == -1) {
- snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
- "%s: Can't get flags for %s: %s", device,
- handle->md.mondevice, strerror(errno));
- del_mon_if(handle, sock_fd, &nlstate, device,
- handle->md.mondevice);
- nl80211_cleanup(&nlstate);
- return PCAP_ERROR;
- }
- ifr.ifr_flags |= IFF_UP|IFF_RUNNING;
- if (ioctl(sock_fd, SIOCSIFFLAGS, &ifr) == -1) {
- snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
- "%s: Can't set flags for %s: %s", device,
- handle->md.mondevice, strerror(errno));
- del_mon_if(handle, sock_fd, &nlstate, device,
- handle->md.mondevice);
- nl80211_cleanup(&nlstate);
- return PCAP_ERROR;
- }
-
- /*
- * Success. Clean up the libnl state.
- */
- nl80211_cleanup(&nlstate);
-
- /*
- * Note that we have to delete the monitor device when we close
- * the handle.
- */
- handle->md.must_do_on_close |= MUST_DELETE_MONIF;
-
- /*
- * Add this to the list of pcaps to close when we exit.
- */
- pcap_add_to_pcaps_to_close(handle);
-
- return 1;
-}
-#endif /* HAVE_LIBNL */
-
#ifdef IW_MODE_MONITOR
/*
* Check whether the device supports the Wireless Extensions.