#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
+#include <ctype.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <linux/if_ether.h>
#include <net/if_arp.h>
#include <poll.h>
+#include <dirent.h>
+
+#ifdef HAVE_LINUX_NET_TSTAMP_H
+#include <linux/net_tstamp.h>
+#include <linux/sockios.h>
+#endif
/*
* Got Wireless Extensions?
#include <netlink/attr.h>
#endif /* HAVE_LIBNL */
+/*
+ * Got ethtool support?
+ */
+#ifdef HAVE_LINUX_ETHTOOL_H
+#include <linux/ethtool.h>
+#include <linux/sockios.h>
+#endif /* HAVE_LINUX_ETHTOOL_H */
+
#include "pcap-int.h"
#include "pcap/sll.h"
#include "pcap/vlan.h"
#include "pcap-septel.h"
#endif /* HAVE_SEPTEL_API */
+#ifdef HAVE_SNF_API
+#include "pcap-snf.h"
+#endif /* HAVE_SNF_API */
+
#ifdef PCAP_SUPPORT_USB
#include "pcap-usb-linux.h"
#endif
static int pcap_activate_linux(pcap_t *);
static int activate_old(pcap_t *);
static int activate_new(pcap_t *);
-static int activate_mmap(pcap_t *);
+static int activate_mmap(pcap_t *, int *);
static int pcap_can_set_rfmon_linux(pcap_t *);
static int pcap_read_linux(pcap_t *, int, pcap_handler, u_char *);
static int pcap_read_packet(pcap_t *, pcap_handler, u_char *);
#define RING_GET_FRAME(h) (((union thdr **)h->buffer)[h->offset])
static void destroy_ring(pcap_t *handle);
-static int create_ring(pcap_t *handle);
+static int create_ring(pcap_t *handle, int *status);
static int prepare_tpacket_socket(pcap_t *handle);
static void pcap_cleanup_linux_mmap(pcap_t *);
static int pcap_read_linux_mmap(pcap_t *, int, pcap_handler , u_char *);
*/
#ifdef HAVE_PF_PACKET_SOCKETS
static int iface_get_id(int fd, const char *device, char *ebuf);
-#endif
+#endif /* HAVE_PF_PACKET_SOCKETS */
static int iface_get_mtu(int fd, const char *device, char *ebuf);
static int iface_get_arptype(int fd, const char *device, char *ebuf);
#ifdef HAVE_PF_PACKET_SOCKETS
static int enter_rfmon_mode(pcap_t *handle, int sock_fd,
const char *device);
#endif /* HAVE_PF_PACKET_SOCKETS */
+static int iface_get_offload(pcap_t *handle);
static int iface_bind_old(int fd, const char *device, char *ebuf);
#ifdef SO_ATTACH_FILTER
= BPF_STMT(BPF_RET | BPF_K, 0);
static struct sock_fprog total_fcode
= { 1, &total_insn };
-#endif
+#endif /* SO_ATTACH_FILTER */
pcap_t *
pcap_create(const char *device, char *ebuf)
}
#endif /* HAVE_SEPTEL_API */
+#ifdef HAVE_SNF_API
+ handle = snf_create(device, ebuf);
+ if (strstr(device, "snf") || handle != NULL)
+ return handle;
+
+#endif /* HAVE_SNF_API */
+
#ifdef PCAP_SUPPORT_BT
if (strstr(device, "bluetooth")) {
return bt_create(device, ebuf);
handle->activate_op = pcap_activate_linux;
handle->can_set_rfmon_op = pcap_can_set_rfmon_linux;
+#if defined(HAVE_LINUX_NET_TSTAMP_H) && defined(PACKET_TIMESTAMP)
+ /*
+ * We claim that we support:
+ *
+ * software time stamps, with no details about their precision;
+ * hardware time stamps, synced to the host time;
+ * hardware time stamps, not synced to the host time.
+ *
+ * XXX - we can't ask a device whether it supports
+ * hardware time stamps, so we just claim all devices do.
+ */
+ handle->tstamp_type_count = 3;
+ handle->tstamp_type_list = malloc(3 * sizeof(u_int));
+ if (handle->tstamp_type_list == NULL) {
+ free(handle);
+ return NULL;
+ }
+ handle->tstamp_type_list[0] = PCAP_TSTAMP_HOST;
+ handle->tstamp_type_list[1] = PCAP_TSTAMP_ADAPTER;
+ handle->tstamp_type_list[2] = PCAP_TSTAMP_ADAPTER_UNSYNCED;
+#endif
+
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.
+ * 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.
*/
/*
return 1;
}
+#ifdef HAVE_LIBNL_2_x
+#define get_nl_errmsg nl_geterror
+#else
+/* libnl 2.x compatibility code */
+
+#define nl_sock nl_handle
+
+static inline struct nl_handle *
+nl_socket_alloc(void)
+{
+ return nl_handle_alloc();
+}
+
+static inline void
+nl_socket_free(struct nl_handle *h)
+{
+ nl_handle_destroy(h);
+}
+
+#define get_nl_errmsg strerror
+
+static inline int
+__genl_ctrl_alloc_cache(struct nl_handle *h, struct nl_cache **cache)
+{
+ struct nl_cache *tmp = genl_ctrl_alloc_cache(h);
+ if (!tmp)
+ return -ENOMEM;
+ *cache = tmp;
+ return 0;
+}
+#define genl_ctrl_alloc_cache __genl_ctrl_alloc_cache
+#endif /* !HAVE_LIBNL_2_x */
+
struct nl80211_state {
- struct nl_handle *nl_handle;
+ struct nl_sock *nl_sock;
struct nl_cache *nl_cache;
struct genl_family *nl80211;
};
static int
nl80211_init(pcap_t *handle, struct nl80211_state *state, const char *device)
{
- state->nl_handle = nl_handle_alloc();
- if (!state->nl_handle) {
+ int err;
+
+ state->nl_sock = nl_socket_alloc();
+ if (!state->nl_sock) {
snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
"%s: failed to allocate netlink handle", device);
return PCAP_ERROR;
}
- if (genl_connect(state->nl_handle)) {
+ if (genl_connect(state->nl_sock)) {
snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
"%s: failed to connect to generic netlink", device);
goto out_handle_destroy;
}
- state->nl_cache = genl_ctrl_alloc_cache(state->nl_handle);
- if (!state->nl_cache) {
+ err = genl_ctrl_alloc_cache(state->nl_sock, &state->nl_cache);
+ if (err < 0) {
snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
- "%s: failed to allocate generic netlink cache", device);
+ "%s: failed to allocate generic netlink cache: %s",
+ device, get_nl_errmsg(-err));
goto out_handle_destroy;
}
out_cache_free:
nl_cache_free(state->nl_cache);
out_handle_destroy:
- nl_handle_destroy(state->nl_handle);
+ nl_socket_free(state->nl_sock);
return PCAP_ERROR;
}
{
genl_family_put(state->nl80211);
nl_cache_free(state->nl_cache);
- nl_handle_destroy(state->nl_handle);
+ nl_socket_free(state->nl_sock);
}
static int
NLA_PUT_STRING(msg, NL80211_ATTR_IFNAME, mondevice);
NLA_PUT_U32(msg, NL80211_ATTR_IFTYPE, NL80211_IFTYPE_MONITOR);
- err = nl_send_auto_complete(state->nl_handle, msg);
+ err = nl_send_auto_complete(state->nl_sock, msg);
if (err < 0) {
+#ifdef HAVE_LIBNL_2_x
+ if (err == -NLE_FAILURE) {
+#else
if (err == -ENFILE) {
+#endif
/*
* Device not available; our caller should just
- * keep trying.
+ * keep trying. (libnl 2.x maps ENFILE to
+ * NLE_FAILURE; it can also map other errors
+ * to that, but there's not much we can do
+ * about that.)
*/
nlmsg_free(msg);
return 0;
*/
snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
"%s: nl_send_auto_complete failed adding %s interface: %s",
- device, mondevice, strerror(-err));
+ device, mondevice, get_nl_errmsg(-err));
nlmsg_free(msg);
return PCAP_ERROR;
}
}
- err = nl_wait_for_ack(state->nl_handle);
+ err = nl_wait_for_ack(state->nl_sock);
if (err < 0) {
+#ifdef HAVE_LIBNL_2_x
+ if (err == -NLE_FAILURE) {
+#else
if (err == -ENFILE) {
+#endif
/*
* Device not available; our caller should just
- * keep trying.
+ * keep trying. (libnl 2.x maps ENFILE to
+ * NLE_FAILURE; it can also map other errors
+ * to that, but there's not much we can do
+ * about that.)
*/
nlmsg_free(msg);
return 0;
*/
snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
"%s: nl_wait_for_ack failed adding %s interface: %s",
- device, mondevice, strerror(-err));
+ device, mondevice, get_nl_errmsg(-err));
nlmsg_free(msg);
return PCAP_ERROR;
}
0, NL80211_CMD_DEL_INTERFACE, 0);
NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, ifindex);
- err = nl_send_auto_complete(state->nl_handle, msg);
+ err = nl_send_auto_complete(state->nl_sock, msg);
if (err < 0) {
- if (err == -ENFILE) {
- /*
- * Device not available; our caller should just
- * keep trying.
- */
- nlmsg_free(msg);
- return 0;
- } else {
- /*
- * Real failure, not just "that device is not
- * available.
- */
- snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
- "%s: nl_send_auto_complete failed deleting %s interface: %s",
- device, mondevice, strerror(-err));
- nlmsg_free(msg);
- return PCAP_ERROR;
- }
+ snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
+ "%s: nl_send_auto_complete failed deleting %s interface: %s",
+ device, mondevice, get_nl_errmsg(-err));
+ nlmsg_free(msg);
+ return PCAP_ERROR;
}
- err = nl_wait_for_ack(state->nl_handle);
+ err = nl_wait_for_ack(state->nl_sock);
if (err < 0) {
- if (err == -ENFILE) {
- /*
- * Device not available; our caller should just
- * keep trying.
- */
- nlmsg_free(msg);
- return 0;
- } else {
- /*
- * Real failure, not just "that device is not
- * available.
- */
- snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
- "%s: nl_wait_for_ack failed adding %s interface: %s",
- device, mondevice, strerror(-err));
- nlmsg_free(msg);
- return PCAP_ERROR;
- }
+ snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
+ "%s: nl_wait_for_ack failed adding %s interface: %s",
+ device, mondevice, get_nl_errmsg(-err));
+ nlmsg_free(msg);
+ return PCAP_ERROR;
}
/*
* to be compatible with older kernels for a while so we are
* trying both methods with the newer method preferred.
*/
-
- if ((status = activate_new(handle)) == 1) {
+ status = activate_new(handle);
+ if (status < 0) {
+ /*
+ * Fatal error with the new way; just fail.
+ * status has the error return; if it's PCAP_ERROR,
+ * handle->errbuf has been set appropriately.
+ */
+ goto fail;
+ }
+ if (status == 1) {
/*
* Success.
* Try to use memory-mapped access.
*/
- switch (activate_mmap(handle)) {
+ switch (activate_mmap(handle, &status)) {
case 1:
- /* we succeeded; nothing more to do */
- return 0;
+ /*
+ * We succeeded. status has been
+ * set to the status to return,
+ * which might be 0, or might be
+ * a PCAP_WARNING_ value.
+ */
+ return status;
case 0:
/*
* Kernel doesn't support it - just continue
* with non-memory-mapped access.
*/
- status = 0;
break;
case -1:
/*
- * We failed to set up to use it, or kernel
- * supports it, but we failed to enable it;
- * return an error. handle->errbuf contains
- * an error message.
+ * We failed to set up to use it, or the kernel
+ * supports it, but we failed to enable it.
+ * status has been set to the error status to
+ * return and, if it's PCAP_ERROR, handle->errbuf
+ * contains the error message.
*/
- status = PCAP_ERROR;
goto fail;
}
}
*/
goto fail;
}
- } else {
- /*
- * Fatal error with the new way; just fail.
- * status has the error return; if it's PCAP_ERROR,
- * handle->errbuf has been set appropriately.
- */
- goto fail;
}
/*
* We set up the socket, but not with memory-mapped access.
*/
+ status = 0;
if (handle->opt.buffer_size != 0) {
/*
* Set the socket buffer size to the specified value.
return 0;
}
-#ifdef HAVE_PROC_NET_DEV
/*
- * Get from "/proc/net/dev" all interfaces listed there; if they're
+ * Get from "/sys/class/net" all interfaces listed there; if they're
* already in the list of interfaces we have, that won't add another
* instance, but if they're not, that'll add them.
*
* although some other types of addresses can be fetched with SIOCGIFADDR,
* we don't bother with them for now.
*
- * We also don't fail if we couldn't open "/proc/net/dev"; we just leave
- * the list of interfaces as is.
+ * We also don't fail if we couldn't open "/sys/class/net"; we just leave
+ * the list of interfaces as is, and return 0, so that we can try
+ * scanning /proc/net/dev.
+ */
+static int
+scan_sys_class_net(pcap_if_t **devlistp, char *errbuf)
+{
+ DIR *sys_class_net_d;
+ int fd;
+ struct dirent *ent;
+ char *p;
+ char name[512]; /* XXX - pick a size */
+ char *q, *saveq;
+ struct ifreq ifrflags;
+ int ret = 1;
+
+ sys_class_net_d = opendir("/sys/class/net");
+ if (sys_class_net_d == NULL && errno == ENOENT)
+ return (0);
+
+ /*
+ * Create a socket from which to fetch interface information.
+ */
+ fd = socket(AF_INET, SOCK_DGRAM, 0);
+ if (fd < 0) {
+ (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
+ "socket: %s", pcap_strerror(errno));
+ (void)closedir(sys_class_net_d);
+ return (-1);
+ }
+
+ for (;;) {
+ errno = 0;
+ ent = readdir(sys_class_net_d);
+ if (ent == NULL) {
+ /*
+ * Error or EOF; if errno != 0, it's an error.
+ */
+ break;
+ }
+
+ /*
+ * Ignore directories (".", "..", and any subdirectories).
+ */
+ if (ent->d_type == DT_DIR)
+ continue;
+
+ /*
+ * Get the interface name.
+ */
+ p = &ent->d_name[0];
+ q = &name[0];
+ while (*p != '\0' && isascii(*p) && !isspace(*p)) {
+ if (*p == ':') {
+ /*
+ * This could be the separator between a
+ * name and an alias number, or it could be
+ * the separator between a name with no
+ * alias number and the next field.
+ *
+ * If there's a colon after digits, it
+ * separates the name and the alias number,
+ * otherwise it separates the name and the
+ * next field.
+ */
+ saveq = q;
+ while (isascii(*p) && isdigit(*p))
+ *q++ = *p++;
+ if (*p != ':') {
+ /*
+ * That was the next field,
+ * not the alias number.
+ */
+ q = saveq;
+ }
+ break;
+ } else
+ *q++ = *p++;
+ }
+ *q = '\0';
+
+ /*
+ * Get the flags for this interface, and skip it if
+ * it's not up.
+ */
+ strncpy(ifrflags.ifr_name, name, sizeof(ifrflags.ifr_name));
+ if (ioctl(fd, SIOCGIFFLAGS, (char *)&ifrflags) < 0) {
+ if (errno == ENXIO || errno == ENODEV)
+ continue;
+ (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
+ "SIOCGIFFLAGS: %.*s: %s",
+ (int)sizeof(ifrflags.ifr_name),
+ ifrflags.ifr_name,
+ pcap_strerror(errno));
+ ret = -1;
+ break;
+ }
+ if (!(ifrflags.ifr_flags & IFF_UP))
+ continue;
+
+ /*
+ * Add an entry for this interface, with no addresses.
+ */
+ if (pcap_add_if(devlistp, name, ifrflags.ifr_flags, NULL,
+ errbuf) == -1) {
+ /*
+ * Failure.
+ */
+ ret = -1;
+ break;
+ }
+ }
+ if (ret != -1) {
+ /*
+ * Well, we didn't fail for any other reason; did we
+ * fail due to an error reading the directory?
+ */
+ if (errno != 0) {
+ (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
+ "Error reading /sys/class/net: %s",
+ pcap_strerror(errno));
+ ret = -1;
+ }
+ }
+
+ (void)close(fd);
+ (void)closedir(sys_class_net_d);
+ return (ret);
+}
+
+/*
+ * Get from "/proc/net/dev" all interfaces listed there; if they're
+ * already in the list of interfaces we have, that won't add another
+ * instance, but if they're not, that'll add them.
+ *
+ * See comments from scan_sys_class_net().
*/
static int
scan_proc_net_dev(pcap_if_t **devlistp, char *errbuf)
int fd;
char linebuf[512];
int linenum;
- unsigned char *p;
+ char *p;
char name[512]; /* XXX - pick a size */
char *q, *saveq;
struct ifreq ifrflags;
int ret = 0;
proc_net_f = fopen("/proc/net/dev", "r");
- if (proc_net_f == NULL)
+ if (proc_net_f == NULL && errno == ENOENT)
return (0);
/*
if (fd < 0) {
(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
"socket: %s", pcap_strerror(errno));
+ (void)fclose(proc_net_f);
return (-1);
}
/*
* Skip leading white space.
*/
- while (*p != '\0' && isspace(*p))
+ while (*p != '\0' && isascii(*p) && isspace(*p))
p++;
if (*p == '\0' || *p == '\n')
continue; /* blank line */
* Get the interface name.
*/
q = &name[0];
- while (*p != '\0' && !isspace(*p)) {
+ while (*p != '\0' && isascii(*p) && !isspace(*p)) {
if (*p == ':') {
/*
* This could be the separator between a
* next field.
*/
saveq = q;
- while (isdigit(*p))
+ while (isascii(*p) && isdigit(*p))
*q++ = *p++;
if (*p != ':') {
/*
(void)fclose(proc_net_f);
return (ret);
}
-#endif /* HAVE_PROC_NET_DEV */
/*
* Description string for the "any" device.
int
pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
{
-#ifdef HAVE_PROC_NET_DEV
+ int ret;
+
/*
- * Read "/proc/net/dev", and add to the list of interfaces all
+ * Read "/sys/class/net", and add to the list of interfaces all
* interfaces listed there that we don't already have, because,
* on Linux, SIOCGIFCONF reports only interfaces with IPv4 addresses,
* and even getifaddrs() won't return information about
- * interfaces with no addresses, so you need to read "/proc/net/dev"
+ * interfaces with no addresses, so you need to read "/sys/class/net"
* to get the names of the rest of the interfaces.
*/
- if (scan_proc_net_dev(alldevsp, errbuf) == -1)
- return (-1);
-#endif
+ ret = scan_sys_class_net(alldevsp, errbuf);
+ if (ret == -1)
+ return (-1); /* failed */
+ if (ret == 0) {
+ /*
+ * No /sys/class/net; try reading /proc/net/dev instead.
+ */
+ if (scan_proc_net_dev(alldevsp, errbuf) == -1)
+ return (-1);
+ }
/*
* Add the "any" device.
return (-1);
#endif /* HAVE_SEPTEL_API */
+#ifdef HAVE_SNF_API
+ if (snf_platform_finddevs(alldevsp, errbuf) < 0)
+ return (-1);
+#endif /* HAVE_SNF_API */
+
#ifdef PCAP_SUPPORT_BT
/*
* Add Bluetooth devices.
}
}
+ /*
+ * NOTE: at this point, we've set both the "len" and "filter"
+ * fields of "fcode". As of the 2.6.32.4 kernel, at least,
+ * those are the only members of the "sock_fprog" structure,
+ * so we initialize every member of that structure.
+ *
+ * If there is anything in "fcode" that is not initialized,
+ * it is either a field added in a later kernel, or it's
+ * padding.
+ *
+ * If a new field is added, this code needs to be updated
+ * to set it correctly.
+ *
+ * If there are no other fields, then:
+ *
+ * if the Linux kernel looks at the padding, it's
+ * buggy;
+ *
+ * if the Linux kernel doesn't look at the padding,
+ * then if some tool complains that we're passing
+ * uninitialized data to the kernel, then the tool
+ * is buggy and needs to understand that it's just
+ * padding.
+ */
if (can_filter_in_kernel) {
if ((err = set_kernel_filter(handle, &fcode)) == 0)
{
return -1;
}
-
#ifdef HAVE_PF_PACKET_SOCKETS
/*
* Map the PACKET_ value to a LINUX_SLL_ value; we
handle->linktype = DLT_RAW;
break;
+#ifndef ARPHRD_IEEE802154
+#define ARPHRD_IEEE802154 804
+#endif
+ case ARPHRD_IEEE802154:
+ handle->linktype = DLT_IEEE802_15_4_NOFCS;
+ break;
+
default:
handle->linktype = -1;
break;
#endif
}
+#ifdef HAVE_PACKET_RING
+/*
+ * Attempt to activate with memory-mapped access.
+ *
+ * On success, returns 1, and sets *status to 0 if there are no warnings
+ * or to a PCAP_WARNING_ code if there is a warning.
+ *
+ * On failure due to lack of support for memory-mapped capture, returns
+ * 0.
+ *
+ * On error, returns -1, and sets *status to the appropriate error code;
+ * if that is PCAP_ERROR, sets handle->errbuf to the appropriate message.
+ */
static int
-activate_mmap(pcap_t *handle)
+activate_mmap(pcap_t *handle, int *status)
{
-#ifdef HAVE_PACKET_RING
int ret;
/*
snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
"can't allocate oneshot buffer: %s",
pcap_strerror(errno));
- return PCAP_ERROR;
+ *status = PCAP_ERROR;
+ return -1;
}
if (handle->opt.buffer_size == 0) {
handle->opt.buffer_size = 2*1024*1024;
}
ret = prepare_tpacket_socket(handle);
- if (ret != 1) {
+ if (ret == -1) {
free(handle->md.oneshot_buffer);
+ *status = PCAP_ERROR;
return ret;
}
- ret = create_ring(handle);
- if (ret != 1) {
+ ret = create_ring(handle, status);
+ if (ret == 0) {
+ /*
+ * We don't support memory-mapped capture; our caller
+ * will fall back on reading from the socket.
+ */
free(handle->md.oneshot_buffer);
- return ret;
+ return 0;
+ }
+ if (ret == -1) {
+ /*
+ * Error attempting to enable memory-mapped capture;
+ * fail. create_ring() has set *status.
+ */
+ free(handle->md.oneshot_buffer);
+ return -1;
}
- /* override some defaults and inherit the other fields from
- * activate_new
- * handle->offset is used to get the current position into the rx ring
- * handle->cc is used to store the ring size */
+ /*
+ * Success. *status has been set either to 0 if there are no
+ * warnings or to a PCAP_WARNING_ value if there is a warning.
+ *
+ * Override some defaults and inherit the other fields from
+ * activate_new.
+ * handle->offset is used to get the current position into the rx ring.
+ * handle->cc is used to store the ring size.
+ */
handle->read_op = pcap_read_linux_mmap;
handle->cleanup_op = pcap_cleanup_linux_mmap;
handle->setfilter_op = pcap_setfilter_linux_mmap;
handle->oneshot_callback = pcap_oneshot_mmap;
handle->selectable_fd = handle->fd;
return 1;
+}
#else /* HAVE_PACKET_RING */
+static int
+activate_mmap(pcap_t *handle _U_, int *status _U_)
+{
return 0;
-#endif /* HAVE_PACKET_RING */
}
+#endif /* HAVE_PACKET_RING */
#ifdef HAVE_PACKET_RING
+/*
+ * Attempt to set the socket to version 2 of the memory-mapped header.
+ * Return 1 if we succeed or if we fail because version 2 isn't
+ * supported; return -1 on any other error, and set handle->errbuf.
+ */
static int
prepare_tpacket_socket(pcap_t *handle)
{
return 1;
}
+/*
+ * Attempt to set up memory-mapped access.
+ *
+ * On success, returns 1, and sets *status to 0 if there are no warnings
+ * or to a PCAP_WARNING_ code if there is a warning.
+ *
+ * On failure due to lack of support for memory-mapped capture, returns
+ * 0.
+ *
+ * On error, returns -1, and sets *status to the appropriate error code;
+ * if that is PCAP_ERROR, sets handle->errbuf to the appropriate message.
+ */
static int
-create_ring(pcap_t *handle)
+create_ring(pcap_t *handle, int *status)
{
unsigned i, j, frames_per_block;
struct tpacket_req req;
+ socklen_t len;
+ unsigned int sk_type, tp_reserve, maclen, tp_hdrlen, netoff, macoff;
+ unsigned int frame_size;
- /* Note that with large snapshot (say 64K) only a few frames
- * will be available in the ring even with pretty large ring size
- * (and a lot of memory will be unused).
- * The snap len should be carefully chosen to achive best
- * performance */
- req.tp_frame_size = TPACKET_ALIGN(handle->snapshot +
- TPACKET_ALIGN(handle->md.tp_hdrlen) +
- sizeof(struct sockaddr_ll));
+ /*
+ * Start out assuming no warnings or errors.
+ */
+ *status = 0;
+
+ /* Note that with large snapshot length (say 64K, which is the default
+ * for recent versions of tcpdump, the value that "-s 0" has given
+ * for a long time with tcpdump, and the default in Wireshark/TShark),
+ * if we use the snapshot length to calculate the frame length,
+ * only a few frames will be available in the ring even with pretty
+ * large ring size (and a lot of memory will be unused).
+ *
+ * Ideally, we should choose a frame length based on the
+ * minimum of the specified snapshot length and the maximum
+ * packet size. That's not as easy as it sounds; consider, for
+ * example, an 802.11 interface in monitor mode, where the
+ * frame would include a radiotap header, where the maximum
+ * radiotap header length is device-dependent.
+ *
+ * So, for now, we just do this for Ethernet devices, where
+ * there's no metadata header, and the link-layer header is
+ * fixed length. We can get the maximum packet size by
+ * adding 18, the Ethernet header length plus the CRC length
+ * (just in case we happen to get the CRC in the packet), to
+ * the MTU of the interface; we fetch the MTU in the hopes
+ * that it reflects support for jumbo frames. (Even if the
+ * interface is just being used for passive snooping, the driver
+ * might set the size of buffers in the receive ring based on
+ * the MTU, so that the MTU limits the maximum size of packets
+ * that we can receive.)
+ *
+ * We don't do that if segmentation/fragmentation or receive
+ * offload are enabled, so we don't get rudely surprised by
+ * "packets" bigger than the MTU. */
+ frame_size = handle->snapshot;
+ if (handle->linktype == DLT_EN10MB) {
+ int mtu;
+ int offload;
+
+ offload = iface_get_offload(handle);
+ if (offload == -1) {
+ *status = PCAP_ERROR;
+ return -1;
+ }
+ if (!offload) {
+ mtu = iface_get_mtu(handle->fd, handle->opt.source,
+ handle->errbuf);
+ if (mtu == -1) {
+ *status = PCAP_ERROR;
+ return -1;
+ }
+ if (frame_size > mtu + 18)
+ frame_size = mtu + 18;
+ }
+ }
+
+ /* NOTE: calculus matching those in tpacket_rcv()
+ * in linux-2.6/net/packet/af_packet.c
+ */
+ len = sizeof(sk_type);
+ if (getsockopt(handle->fd, SOL_SOCKET, SO_TYPE, &sk_type, &len) < 0) {
+ snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "getsockopt: %s", pcap_strerror(errno));
+ *status = PCAP_ERROR;
+ return -1;
+ }
+#ifdef PACKET_RESERVE
+ len = sizeof(tp_reserve);
+ if (getsockopt(handle->fd, SOL_PACKET, PACKET_RESERVE, &tp_reserve, &len) < 0) {
+ if (errno != ENOPROTOOPT) {
+ /*
+ * ENOPROTOOPT means "kernel doesn't support
+ * PACKET_RESERVE", in which case we fall back
+ * as best we can.
+ */
+ snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "getsockopt: %s", pcap_strerror(errno));
+ *status = PCAP_ERROR;
+ return -1;
+ }
+ tp_reserve = 0; /* older kernel, reserve not supported */
+ }
+#else
+ tp_reserve = 0; /* older kernel, reserve not supported */
+#endif
+ maclen = (sk_type == SOCK_DGRAM) ? 0 : MAX_LINKHEADER_SIZE;
+ /* XXX: in the kernel maclen is calculated from
+ * LL_ALLOCATED_SPACE(dev) and vnet_hdr.hdr_len
+ * in: packet_snd() in linux-2.6/net/packet/af_packet.c
+ * then packet_alloc_skb() in linux-2.6/net/packet/af_packet.c
+ * then sock_alloc_send_pskb() in linux-2.6/net/core/sock.c
+ * but I see no way to get those sizes in userspace,
+ * like for instance with an ifreq ioctl();
+ * the best thing I've found so far is MAX_HEADER in the kernel
+ * part of linux-2.6/include/linux/netdevice.h
+ * which goes up to 128+48=176; since pcap-linux.c defines
+ * a MAX_LINKHEADER_SIZE of 256 which is greater than that,
+ * let's use it.. maybe is it even large enough to directly
+ * replace macoff..
+ */
+ tp_hdrlen = TPACKET_ALIGN(handle->md.tp_hdrlen) + sizeof(struct sockaddr_ll) ;
+ netoff = TPACKET_ALIGN(tp_hdrlen + (maclen < 16 ? 16 : maclen)) + tp_reserve;
+ /* NOTE: AFAICS tp_reserve may break the TPACKET_ALIGN of
+ * netoff, which contradicts
+ * linux-2.6/Documentation/networking/packet_mmap.txt
+ * documenting that:
+ * "- Gap, chosen so that packet data (Start+tp_net)
+ * aligns to TPACKET_ALIGNMENT=16"
+ */
+ /* NOTE: in linux-2.6/include/linux/skbuff.h:
+ * "CPUs often take a performance hit
+ * when accessing unaligned memory locations"
+ */
+ macoff = netoff - maclen;
+ req.tp_frame_size = TPACKET_ALIGN(macoff + frame_size);
req.tp_frame_nr = handle->opt.buffer_size/req.tp_frame_size;
/* compute the minumum block size that will handle this frame.
frames_per_block = req.tp_block_size/req.tp_frame_size;
+ /*
+ * PACKET_TIMESTAMP was added after linux/net_tstamp.h was,
+ * so we check for PACKET_TIMESTAMP. We check for
+ * linux/net_tstamp.h just in case a system somehow has
+ * PACKET_TIMESTAMP but not linux/net_tstamp.h; that might
+ * be unnecessary.
+ *
+ * SIOCSHWTSTAMP was introduced in the patch that introduced
+ * linux/net_tstamp.h, so we don't bother checking whether
+ * SIOCSHWTSTAMP is defined (if your Linux system has
+ * linux/net_tstamp.h but doesn't define SIOCSHWTSTAMP, your
+ * Linux system is badly broken).
+ */
+#if defined(HAVE_LINUX_NET_TSTAMP_H) && defined(PACKET_TIMESTAMP)
+ /*
+ * If we were told to do so, ask the kernel and the driver
+ * to use hardware timestamps.
+ *
+ * Hardware timestamps are only supported with mmapped
+ * captures.
+ */
+ if (handle->opt.tstamp_type == PCAP_TSTAMP_ADAPTER ||
+ handle->opt.tstamp_type == PCAP_TSTAMP_ADAPTER_UNSYNCED) {
+ struct hwtstamp_config hwconfig;
+ struct ifreq ifr;
+ int timesource;
+
+ /*
+ * Ask for hardware time stamps on all packets,
+ * including transmitted packets.
+ */
+ memset(&hwconfig, 0, sizeof(hwconfig));
+ hwconfig.tx_type = HWTSTAMP_TX_ON;
+ hwconfig.rx_filter = HWTSTAMP_FILTER_ALL;
+
+ memset(&ifr, 0, sizeof(ifr));
+ strcpy(ifr.ifr_name, handle->opt.source);
+ ifr.ifr_data = (void *)&hwconfig;
+
+ if (ioctl(handle->fd, SIOCSHWTSTAMP, &ifr) < 0) {
+ switch (errno) {
+
+ case EPERM:
+ /*
+ * Treat this as an error, as the
+ * user should try to run this
+ * with the appropriate privileges -
+ * and, if they can't, shouldn't
+ * try requesting hardware time stamps.
+ */
+ *status = PCAP_ERROR_PERM_DENIED;
+ return -1;
+
+ case EOPNOTSUPP:
+ /*
+ * Treat this as a warning, as the
+ * only way to fix the warning is to
+ * get an adapter that supports hardware
+ * time stamps. We'll just fall back
+ * on the standard host time stamps.
+ */
+ *status = PCAP_WARNING_TSTAMP_TYPE_NOTSUP;
+ break;
+
+ default:
+ snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
+ "SIOCSHWTSTAMP failed: %s",
+ pcap_strerror(errno));
+ *status = PCAP_ERROR;
+ return -1;
+ }
+ } else {
+ /*
+ * Well, that worked. Now specify the type of
+ * hardware time stamp we want for this
+ * socket.
+ */
+ if (handle->opt.tstamp_type == PCAP_TSTAMP_ADAPTER) {
+ /*
+ * Hardware timestamp, synchronized
+ * with the system clock.
+ */
+ timesource = SOF_TIMESTAMPING_SYS_HARDWARE;
+ } else {
+ /*
+ * PCAP_TSTAMP_ADAPTER_UNSYNCED - hardware
+ * timestamp, not synchronized with the
+ * system clock.
+ */
+ timesource = SOF_TIMESTAMPING_RAW_HARDWARE;
+ }
+ if (setsockopt(handle->fd, SOL_PACKET, PACKET_TIMESTAMP,
+ (void *)×ource, sizeof(timesource))) {
+ snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
+ "can't set PACKET_TIMESTAMP: %s",
+ pcap_strerror(errno));
+ *status = PCAP_ERROR;
+ return -1;
+ }
+ }
+ }
+#endif /* HAVE_LINUX_NET_TSTAMP_H && PACKET_TIMESTAMP */
+
/* ask the kernel to create the ring */
retry:
req.tp_block_nr = req.tp_frame_nr / frames_per_block;
snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
"can't create rx ring on packet socket: %s",
pcap_strerror(errno));
+ *status = PCAP_ERROR;
return -1;
}
/* clear the allocated ring on error*/
destroy_ring(handle);
+ *status = PCAP_ERROR;
return -1;
}
pcap_strerror(errno));
destroy_ring(handle);
+ *status = PCAP_ERROR;
return -1;
}
return 0;
}
+/*
+ * Find out if we have any form of fragmentation/reassembly offloading.
+ */
+#ifdef SIOCETHTOOL
+static int
+iface_ethtool_ioctl(pcap_t *handle, int cmd, const char *cmdname)
+{
+ struct ifreq ifr;
+ struct ethtool_value eval;
+
+ memset(&ifr, 0, sizeof(ifr));
+ strncpy(ifr.ifr_name, handle->opt.source, sizeof(ifr.ifr_name));
+ eval.cmd = cmd;
+ ifr.ifr_data = (caddr_t)&eval;
+ if (ioctl(handle->fd, SIOCETHTOOL, &ifr) == -1) {
+ if (errno == EOPNOTSUPP) {
+ /*
+ * OK, let's just return 0, which, in our
+ * case, either means "no, what we're asking
+ * about is not enabled" or "all the flags
+ * are clear (i.e., nothing is enabled)".
+ */
+ return 0;
+ }
+ snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
+ "%s: SIOETHTOOL(%s) ioctl failed: %s", handle->opt.source,
+ cmdname, strerror(errno));
+ return -1;
+ }
+ return eval.data;
+}
+
+static int
+iface_get_offload(pcap_t *handle)
+{
+ int ret;
+
+ ret = iface_ethtool_ioctl(handle, ETHTOOL_GTSO, "ETHTOOL_GTSO");
+ if (ret == -1)
+ return -1;
+ if (ret)
+ return 1; /* TCP segmentation offloading on */
+
+ ret = iface_ethtool_ioctl(handle, ETHTOOL_GUFO, "ETHTOOL_GUFO");
+ if (ret == -1)
+ return -1;
+ if (ret)
+ return 1; /* UDP fragmentation offloading on */
+
+ /*
+ * XXX - will this cause large unsegmented packets to be
+ * handed to PF_PACKET sockets on transmission? If not,
+ * this need not be checked.
+ */
+ ret = iface_ethtool_ioctl(handle, ETHTOOL_GGSO, "ETHTOOL_GGSO");
+ if (ret == -1)
+ return -1;
+ if (ret)
+ return 1; /* generic segmentation offloading on */
+
+ ret = iface_ethtool_ioctl(handle, ETHTOOL_GFLAGS, "ETHTOOL_GFLAGS");
+ if (ret == -1)
+ return -1;
+ if (ret & ETH_FLAG_LRO)
+ return 1; /* large receive offloading on */
+
+ /*
+ * XXX - will this cause large reassembled packets to be
+ * handed to PF_PACKET sockets on receipt? If not,
+ * this need not be checked.
+ */
+ ret = iface_ethtool_ioctl(handle, ETHTOOL_GGRO, "ETHTOOL_GGRO");
+ if (ret == -1)
+ return -1;
+ if (ret)
+ return 1; /* generic (large) receive offloading on */
+
+ return 0;
+}
+#else /* SIOCETHTOOL */
+static int
+iface_get_offload(pcap_t *handle _U_)
+{
+ /*
+ * XXX - do we need to get this information if we don't
+ * have the ethtool ioctls? If so, how do we do that?
+ */
+ return 0;
+}
+#endif /* SIOCETHTOOL */
+
#endif /* HAVE_PF_PACKET_SOCKETS */
/* ===== Functions to interface to the older kernels ================== */
projects / libpcap / blobdiff