#include <fcntl.h>
#include <string.h>
#include <limits.h>
+#include <sys/stat.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/utsname.h>
#include <sys/mman.h>
#include <linux/if.h>
+#include <linux/if_packet.h>
#include <netinet/in.h>
#include <linux/if_ether.h>
#include <net/if_arp.h>
#include "pcap-can-linux.h"
#endif
+#if PCAP_SUPPORT_CANUSB
+#include "pcap-canusb-linux.h"
+#endif
+
#ifdef PCAP_SUPPORT_NETFILTER
#include "pcap-netfilter-linux.h"
#endif
/*
* Prototypes for internal functions and methods.
*/
-static void map_arphrd_to_dlt(pcap_t *, int, int);
+static void map_arphrd_to_dlt(pcap_t *, int, int, const char *, int);
#ifdef HAVE_PF_PACKET_SOCKETS
static short int map_packet_type_to_sll_type(short int);
#endif
}
#endif
+#if PCAP_SUPPORT_CANUSB
+ if (strstr(device, "canusb")) {
+ return canusb_create(device, ebuf);
+ }
+#endif
+
#ifdef PCAP_SUPPORT_CAN
- if (strstr(device, "can") || strstr(device, "vcan")) {
+ if ((strncmp(device, "can", 3) == 0 && isdigit(device[3])) ||
+ (strncmp(device, "vcan", 4) == 0 && isdigit(device[4]))) {
return can_create(device, ebuf);
}
#endif
}
#if defined(HAVE_PACKET_AUXDATA) && defined(HAVE_LINUX_TPACKET_AUXDATA_TP_VLAN_TCI)
- for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
- struct tpacket_auxdata *aux;
- unsigned int len;
- struct vlan_tag *tag;
-
- if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct tpacket_auxdata)) ||
- cmsg->cmsg_level != SOL_PACKET ||
- cmsg->cmsg_type != PACKET_AUXDATA)
- continue;
+ if (handle->md.vlan_offset != -1) {
+ for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
+ struct tpacket_auxdata *aux;
+ unsigned int len;
+ struct vlan_tag *tag;
- aux = (struct tpacket_auxdata *)CMSG_DATA(cmsg);
- if (aux->tp_vlan_tci == 0)
- continue;
+ if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct tpacket_auxdata)) ||
+ cmsg->cmsg_level != SOL_PACKET ||
+ cmsg->cmsg_type != PACKET_AUXDATA)
+ continue;
- len = packet_len > iov.iov_len ? iov.iov_len : packet_len;
- if (len < 2 * ETH_ALEN)
- break;
+ aux = (struct tpacket_auxdata *)CMSG_DATA(cmsg);
+#if defined(TP_STATUS_VLAN_VALID)
+ if ((aux->tp_vlan_tci == 0) && !(aux->tp_status & TP_STATUS_VLAN_VALID))
+#else
+ if (aux->tp_vlan_tci == 0) /* this is ambigious but without the
+ TP_STATUS_VLAN_VALID flag, there is
+ nothing that we can do */
+#endif
+ continue;
- bp -= VLAN_TAG_LEN;
- memmove(bp, bp + VLAN_TAG_LEN, 2 * ETH_ALEN);
+ len = packet_len > iov.iov_len ? iov.iov_len : packet_len;
+ if (len < (unsigned int) handle->md.vlan_offset)
+ break;
+
+ bp -= VLAN_TAG_LEN;
+ memmove(bp, bp + VLAN_TAG_LEN, handle->md.vlan_offset);
- tag = (struct vlan_tag *)(bp + 2 * ETH_ALEN);
- tag->vlan_tpid = htons(ETH_P_8021Q);
- tag->vlan_tci = htons(aux->tp_vlan_tci);
+ tag = (struct vlan_tag *)(bp + handle->md.vlan_offset);
+ tag->vlan_tpid = htons(ETH_P_8021Q);
+ tag->vlan_tci = htons(aux->tp_vlan_tci);
- packet_len += VLAN_TAG_LEN;
+ packet_len += VLAN_TAG_LEN;
+ }
}
#endif /* defined(HAVE_PACKET_AUXDATA) && defined(HAVE_LINUX_TPACKET_AUXDATA_TP_VLAN_TCI) */
#endif /* HAVE_PF_PACKET_SOCKETS */
DIR *sys_class_net_d;
int fd;
struct dirent *ent;
+ char subsystem_path[PATH_MAX+1];
+ struct stat statb;
char *p;
char name[512]; /* XXX - pick a size */
char *q, *saveq;
}
/*
- * Ignore directories (".", "..", and any subdirectories).
+ * Ignore "." and "..".
*/
- if (ent->d_type == DT_DIR)
+ if (strcmp(ent->d_name, ".") == 0 ||
+ strcmp(ent->d_name, "..") == 0)
continue;
+ /*
+ * Ignore plain files; they do not have subdirectories
+ * and thus have no attributes.
+ */
+ if (ent->d_type == DT_REG)
+ continue;
+
+ /*
+ * Is there an "ifindex" file under that name?
+ * (We don't care whether it's a directory or
+ * a symlink; older kernels have directories
+ * for devices, newer kernels have symlinks to
+ * directories.)
+ */
+ snprintf(subsystem_path, sizeof subsystem_path,
+ "/sys/class/net/%s/ifindex", ent->d_name);
+ if (lstat(subsystem_path, &statb) != 0) {
+ /*
+ * Stat failed. Either there was an error
+ * other than ENOENT, and we don't know if
+ * this is an interface, or it's ENOENT,
+ * and either some part of "/sys/class/net/{if}"
+ * disappeared, in which case it probably means
+ * the interface disappeared, or there's no
+ * "ifindex" file, which means it's not a
+ * network interface.
+ */
+ continue;
+ }
+
/*
* Get the interface name.
*/
return (-1);
#endif
+#if PCAP_SUPPORT_CANUSB
+ if (canusb_platform_finddevs(alldevsp, errbuf) < 0)
+ return (-1);
+#endif
+
return (0);
}
}
#endif
+static int
+is_wifi(int sock_fd
+#ifndef IW_MODE_MONITOR
+_U_
+#endif
+, const char *device)
+{
+ char *pathstr;
+ struct stat statb;
+#ifdef IW_MODE_MONITOR
+ char errbuf[PCAP_ERRBUF_SIZE];
+#endif
+
+ /*
+ * See if there's a sysfs wireless directory for it.
+ * If so, it's a wireless interface.
+ */
+ if (asprintf(&pathstr, "/sys/class/net/%s/wireless", device) == -1) {
+ /*
+ * Just give up here.
+ */
+ return 0;
+ }
+ if (stat(pathstr, &statb) == 0) {
+ free(pathstr);
+ return 1;
+ }
+ free(pathstr);
+
+#ifdef IW_MODE_MONITOR
+ /*
+ * OK, maybe it's not wireless, or maybe this kernel doesn't
+ * support sysfs. Try the wireless extensions.
+ */
+ if (has_wext(sock_fd, device, errbuf) == 1) {
+ /*
+ * It supports the wireless extensions, so it's a Wi-Fi
+ * device.
+ */
+ return 1;
+ }
+#endif
+ return 0;
+}
+
/*
* Linux uses the ARP hardware type to identify the type of an
* interface. pcap uses the DLT_xxx constants for this. This
*
* Sets the link type to -1 if unable to map the type.
*/
-static void map_arphrd_to_dlt(pcap_t *handle, int arptype, int cooked_ok)
+static void map_arphrd_to_dlt(pcap_t *handle, int sock_fd, int arptype,
+ const char *device, int cooked_ok)
{
+ static const char cdma_rmnet[] = "cdma_rmnet";
+
switch (arptype) {
case ARPHRD_ETHER:
/*
- * This is (presumably) a real Ethernet capture; give it a
+ * For various annoying reasons having to do with DHCP
+ * software, some versions of Android give the mobile-
+ * phone-network interface an ARPHRD_ value of
+ * ARPHRD_ETHER, even though the packets supplied by
+ * that interface have no link-layer header, and begin
+ * with an IP header, so that the ARPHRD_ value should
+ * be ARPHRD_NONE.
+ *
+ * Detect those devices by checking the device name, and
+ * use DLT_RAW for them.
+ */
+ if (strncmp(device, cdma_rmnet, sizeof cdma_rmnet - 1) == 0) {
+ handle->linktype = DLT_RAW;
+ return;
+ }
+
+ /*
+ * Is this a real Ethernet device? If so, give it a
* link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so
* that an application can let you choose it, in case you're
* capturing DOCSIS traffic that a Cisco Cable Modem
* DOCSIS frames out on the wire inside the low-level
* Ethernet framing).
*
- * XXX - are there any sorts of "fake Ethernet" that have
- * ARPHRD_ETHER but that *shouldn't offer DLT_DOCSIS as
+ * XXX - are there any other sorts of "fake Ethernet" that
+ * have ARPHRD_ETHER but that shouldn't offer DLT_DOCSIS as
* a Cisco CMTS won't put traffic onto it or get traffic
* bridged onto it? ISDN is handled in "activate_new()",
- * as we fall back on cooked mode there; are there any
+ * as we fall back on cooked mode there, and we use
+ * is_wifi() to check for 802.11 devices; are there any
* others?
*/
- handle->dlt_list = (u_int *) malloc(sizeof(u_int) * 2);
- /*
- * If that fails, just leave the list empty.
- */
- if (handle->dlt_list != NULL) {
- handle->dlt_list[0] = DLT_EN10MB;
- handle->dlt_list[1] = DLT_DOCSIS;
- handle->dlt_count = 2;
+ if (!is_wifi(sock_fd, device)) {
+ /*
+ * It's not a Wi-Fi device; offer DOCSIS.
+ */
+ handle->dlt_list = (u_int *) malloc(sizeof(u_int) * 2);
+ /*
+ * If that fails, just leave the list empty.
+ */
+ if (handle->dlt_list != NULL) {
+ handle->dlt_list[0] = DLT_EN10MB;
+ handle->dlt_list[1] = DLT_DOCSIS;
+ handle->dlt_count = 2;
+ }
}
/* FALLTHROUGH */
close(sock_fd);
return arptype;
}
- map_arphrd_to_dlt(handle, arptype, 1);
+ map_arphrd_to_dlt(handle, sock_fd, arptype, device, 1);
if (handle->linktype == -1 ||
handle->linktype == DLT_LINUX_SLL ||
handle->linktype == DLT_LINUX_IRDA ||
}
handle->bufsize = handle->snapshot;
+ /*
+ * Set the offset at which to insert VLAN tags.
+ */
+ switch (handle->linktype) {
+
+ case DLT_EN10MB:
+ handle->md.vlan_offset = 2 * ETH_ALEN;
+ break;
+
+ case DLT_LINUX_SLL:
+ handle->md.vlan_offset = 14;
+ break;
+
+ default:
+ handle->md.vlan_offset = -1; /* unknown */
+ break;
+ }
+
/* Save the socket FD in the pcap structure */
handle->fd = sock_fd;
if (tp_mac + tp_snaplen > handle->bufsize) {
snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
"corrupted frame on kernel ring mac "
- "offset %d + caplen %d > frame len %d",
+ "offset %u + caplen %u > frame len %d",
tp_mac, tp_snaplen, handle->bufsize);
return -1;
}
}
#ifdef HAVE_TPACKET2
- if (handle->md.tp_version == TPACKET_V2 && h.h2->tp_vlan_tci &&
- tp_snaplen >= 2 * ETH_ALEN) {
+ if ((handle->md.tp_version == TPACKET_V2) &&
+#if defined(TP_STATUS_VLAN_VALID)
+ (h.h2->tp_vlan_tci || (h.h2->tp_status & TP_STATUS_VLAN_VALID)) &&
+#else
+ h.h2->tp_vlan_tci &&
+#endif
+ handle->md.vlan_offset != -1 &&
+ tp_snaplen >= (unsigned int) handle->md.vlan_offset) {
struct vlan_tag *tag;
bp -= VLAN_TAG_LEN;
- memmove(bp, bp + VLAN_TAG_LEN, 2 * ETH_ALEN);
+ memmove(bp, bp + VLAN_TAG_LEN, handle->md.vlan_offset);
- tag = (struct vlan_tag *)(bp + 2 * ETH_ALEN);
+ tag = (struct vlan_tag *)(bp + handle->md.vlan_offset);
tag->vlan_tpid = htons(ETH_P_8021Q);
tag->vlan_tci = htons(h.h2->tp_vlan_tci);
eval.cmd = cmd;
ifr.ifr_data = (caddr_t)&eval;
if (ioctl(handle->fd, SIOCETHTOOL, &ifr) == -1) {
- if (errno == EOPNOTSUPP) {
+ if (errno == EOPNOTSUPP || errno == EINVAL) {
/*
* OK, let's just return 0, which, in our
* case, either means "no, what we're asking
* Try to find the DLT_ type corresponding to that
* link-layer type.
*/
- map_arphrd_to_dlt(handle, arptype, 0);
+ map_arphrd_to_dlt(handle, handle->fd, arptype, device, 0);
if (handle->linktype == -1) {
snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
"unknown arptype %d", arptype);
*/
handle->offset = 0;
+ /*
+ * SOCK_PACKET sockets don't supply information from
+ * stripped VLAN tags.
+ */
+ handle->md.vlan_offset = -1; /* unknown */
+
return 1;
}
projects / libpcap / blobdiff