int nl80211_create_monitor_interface(struct nl80211_data* ctx)
{
if (ctx->monitor_ifidx < 0) {
// create monitor
ctx->monitor_ifidx = nl80211_create_iface_once(ctx, NULL, NULL);
if (ctx->monitor_ifidx == -EOPNOTSUPP) {
/*
* This is backward compatibility for a few versions of
* the kernel only that didn't advertise the right
* attributes for the only driver that then supported
* AP mode w/o monitor -- ath6kl.
*/
fprintf(stderr, "nl80211: Driver does not support monitor interface type - try to run without it\n");
}
} else {
fprintf(stderr, "nl80211: re-use monitor '%s' index: %d\n",ctx->monitor_name, ctx->monitor_ifidx);
}
if (ctx->monitor_ifidx < 0)
return -1;
// interface up!
if (linux_set_iface_flags(ctx->cfg->ioctl_sock, ctx->monitor_name, 1))
goto error;
// create socket on monitor interface
{
struct sockaddr_ll ll;
int optval;
socklen_t optlen;
memset(&ll, 0, sizeof(ll));
ll.sll_family = AF_PACKET;
ll.sll_ifindex = ctx->monitor_ifidx;
ctx->monitor_sock = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
if (ctx->monitor_sock < 0) {
fprintf(stderr, "nl80211: socket[PF_PACKET,SOCK_RAW] failed: %s\n", strerror(errno));
goto error;
}
if (add_monitor_filter(ctx->monitor_sock)) {
fprintf(stderr, "Failed to set socket filter for monitor interface; do filtering in user space\n");
/* This works, but will cost in performance. */
}
if (bind(ctx->monitor_sock, (struct sockaddr *) &ll, sizeof(ll)) < 0) {
fprintf(stderr, "nl80211: monitor socket bind failed: %s\n", strerror(errno));
goto error;
}
optlen = sizeof(optval);
optval = 20;
if (setsockopt(ctx->monitor_sock, SOL_SOCKET, SO_PRIORITY, &optval, optlen)) {
fprintf(stderr, "nl80211: Failed to set socket priority: %s\n", strerror(errno));
goto error;
}
if (eloop_register_read_sock(ctx->monitor_sock, handle_monitor_read, ctx, NULL)) {
fprintf(stderr, "nl80211: Could not register monitor read socket\n");
goto error;
}
}
return 0;
error:
nl80211_remove_monitor_interface(ctx);
return -1;
}
int nl80211_create_monitor_interface(struct wpa_driver_nl80211_data *drv)
{
char buf[IFNAMSIZ];
struct sockaddr_ll ll;
int optval;
socklen_t optlen;
if (drv->monitor_ifidx >= 0) {
drv->monitor_refcount++;
wpa_printf(MSG_DEBUG, "nl80211: Re-use existing monitor interface: refcount=%d",
drv->monitor_refcount);
return 0;
}
if (os_strncmp(drv->first_bss->ifname, "p2p-", 4) == 0) {
/*
* P2P interface name is of the format p2p-%s-%d. For monitor
* interface name corresponding to P2P GO, replace "p2p-" with
* "mon-" to retain the same interface name length and to
* indicate that it is a monitor interface.
*/
snprintf(buf, IFNAMSIZ, "mon-%s", drv->first_bss->ifname + 4);
} else {
/* Non-P2P interface with AP functionality. */
snprintf(buf, IFNAMSIZ, "mon.%s", drv->first_bss->ifname);
}
buf[IFNAMSIZ - 1] = '\0';
drv->monitor_ifidx =
nl80211_create_iface(drv, buf, NL80211_IFTYPE_MONITOR, NULL,
0, NULL, NULL, 0);
if (drv->monitor_ifidx == -EOPNOTSUPP) {
/*
* This is backward compatibility for a few versions of
* the kernel only that didn't advertise the right
* attributes for the only driver that then supported
* AP mode w/o monitor -- ath6kl.
*/
wpa_printf(MSG_DEBUG, "nl80211: Driver does not support "
"monitor interface type - try to run without it");
drv->device_ap_sme = 1;
}
if (drv->monitor_ifidx < 0)
return -1;
if (linux_set_iface_flags(drv->global->ioctl_sock, buf, 1))
goto error;
memset(&ll, 0, sizeof(ll));
ll.sll_family = AF_PACKET;
ll.sll_ifindex = drv->monitor_ifidx;
drv->monitor_sock = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
if (drv->monitor_sock < 0) {
wpa_printf(MSG_ERROR, "nl80211: socket[PF_PACKET,SOCK_RAW] failed: %s",
strerror(errno));
goto error;
}
if (add_monitor_filter(drv->monitor_sock)) {
wpa_printf(MSG_INFO, "Failed to set socket filter for monitor "
"interface; do filtering in user space");
/* This works, but will cost in performance. */
}
if (bind(drv->monitor_sock, (struct sockaddr *) &ll, sizeof(ll)) < 0) {
wpa_printf(MSG_ERROR, "nl80211: monitor socket bind failed: %s",
strerror(errno));
goto error;
}
optlen = sizeof(optval);
optval = 20;
if (setsockopt
(drv->monitor_sock, SOL_SOCKET, SO_PRIORITY, &optval, optlen)) {
wpa_printf(MSG_ERROR, "nl80211: Failed to set socket priority: %s",
strerror(errno));
goto error;
}
if (eloop_register_read_sock(drv->monitor_sock, handle_monitor_read,
drv, NULL)) {
wpa_printf(MSG_INFO, "nl80211: Could not register monitor read socket");
goto error;
}
drv->monitor_refcount++;
return 0;
error:
nl80211_remove_monitor_interface(drv);
return -1;
}
