Add a new frame watch API
This new API is independent of netdev.c and allows actually unregistering from receiving notifications of frames, although with some quirks. The current API only allowed the callback for a registration to be forgotten but our process and/or the kernel would still be woken up when matching frames were received because the kernel had no frame unregister call. In the new API you can supply a group-id paramter when registering frames. If it is non-zero the frame_watch_group_remove() call can be used to remove all frame registrations that had a given group-id by closing the netlink socket on which the notifications would be received. This means though that it's a slightly costly operation. The file is named frame-xchg.c because I'm thinking of also adding utilities for sending frames and waiting for one of a number of replies and handling the acked/un-acked information.
This commit is contained in:
Andrew Zaborowski
Denis Kenzior
parent
5888f66258
commit
6484b7dbb6
|
|
@ -227,6 +227,7 @@ src_iwd_SOURCES = src/main.c linux/nl80211.h src/iwd.h src/missing.h \
|
|||
src/p2putil.h src/p2putil.c \
|
||||
src/module.h src/module.c \
|
||||
src/rrm.c \
|
||||
src/frame-xchg.h src/frame-xchg.c \
|
||||
$(eap_sources) \
|
||||
$(builtin_sources)
|
||||
|
||||
|
|
|
|||
|
|
@ -0,0 +1,476 @@
|
|||
/*
|
||||
*
|
||||
* Wireless daemon for Linux
|
||||
*
|
||||
* Copyright (C) 2020 Intel Corporation. All rights reserved.
|
||||
*
|
||||
* This library is free software; you can redistribute it and/or
|
||||
* modify it under the terms of the GNU Lesser General Public
|
||||
* License as published by the Free Software Foundation; either
|
||||
* version 2.1 of the License, or (at your option) any later version.
|
||||
*
|
||||
* This library is distributed in the hope that it will be useful,
|
||||
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
* Lesser General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU Lesser General Public
|
||||
* License along with this library; if not, write to the Free Software
|
||||
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
||||
*
|
||||
*/
|
||||
|
||||
#ifdef HAVE_CONFIG_H
|
||||
#include <config.h>
|
||||
#endif
|
||||
|
||||
#include <errno.h>
|
||||
|
||||
#include <ell/ell.h>
|
||||
|
||||
#include "linux/nl80211.h"
|
||||
|
||||
#include "src/iwd.h"
|
||||
#include "src/module.h"
|
||||
#include "src/mpdu.h"
|
||||
#include "src/util.h"
|
||||
#include "src/watchlist.h"
|
||||
#include "src/nl80211util.h"
|
||||
#include "src/netdev.h"
|
||||
#include "src/frame-xchg.h"
|
||||
|
||||
struct watch_group {
|
||||
/*
|
||||
* Group IDs, except 0, are per wdev for user's convenience.
|
||||
* I.e. group 1 can be used for P2P discovery and be removed as
|
||||
* soon as the scan is over on a given device without interfering
|
||||
* with scans on other devices. This means a module can name
|
||||
* all the groups it's going to need in a static enum.
|
||||
* Group 0 is the default group and uses the iwd_get_genl() netlink
|
||||
* socket shared with all its other users, meaning that it can not
|
||||
* be closed through the watch API. It is to be used for watches
|
||||
* that don't need to be unregistered before the virtual interface
|
||||
* type change or destruction, which are the two events that
|
||||
* implicitly unregister all existing watches.
|
||||
*/
|
||||
uint32_t id;
|
||||
uint64_t wdev_id;
|
||||
uint32_t unicast_watch_id;
|
||||
struct l_genl *genl;
|
||||
struct l_genl_family *nl80211;
|
||||
struct watchlist watches;
|
||||
};
|
||||
|
||||
struct frame_watch {
|
||||
uint64_t wdev_id;
|
||||
uint16_t frame_type;
|
||||
uint8_t *prefix;
|
||||
size_t prefix_len;
|
||||
struct watch_group *group;
|
||||
struct watchlist_item super;
|
||||
};
|
||||
|
||||
static struct l_queue *watch_groups;
|
||||
|
||||
struct wdev_info {
|
||||
uint64_t id;
|
||||
uint32_t iftype;
|
||||
};
|
||||
|
||||
static struct l_queue *wdevs;
|
||||
|
||||
struct frame_prefix_info {
|
||||
uint16_t frame_type;
|
||||
const uint8_t *body;
|
||||
size_t body_len;
|
||||
uint64_t wdev_id;
|
||||
};
|
||||
|
||||
static bool frame_watch_match_prefix(const void *a, const void *b)
|
||||
{
|
||||
const struct watchlist_item *item = a;
|
||||
const struct frame_watch *watch =
|
||||
l_container_of(item, struct frame_watch, super);
|
||||
const struct frame_prefix_info *info = b;
|
||||
|
||||
return watch->frame_type == info->frame_type &&
|
||||
watch->prefix_len <= info->body_len &&
|
||||
(watch->prefix_len == 0 ||
|
||||
!memcmp(watch->prefix, info->body, watch->prefix_len)) &&
|
||||
info->wdev_id == watch->wdev_id;
|
||||
}
|
||||
|
||||
static void frame_watch_unicast_notify(struct l_genl_msg *msg, void *user_data)
|
||||
{
|
||||
struct watch_group *group = user_data;
|
||||
const uint64_t *wdev_id = NULL;
|
||||
const uint32_t *ifindex = NULL;
|
||||
struct l_genl_attr attr;
|
||||
uint16_t type, len, frame_len;
|
||||
const void *data;
|
||||
const struct mmpdu_header *mpdu = NULL;
|
||||
const uint8_t *body;
|
||||
struct frame_prefix_info info;
|
||||
int rssi = 0; /* No-RSSI flag value */
|
||||
|
||||
if (l_genl_msg_get_command(msg) != NL80211_CMD_FRAME)
|
||||
return;
|
||||
|
||||
if (!l_genl_attr_init(&attr, msg))
|
||||
return;
|
||||
|
||||
while (l_genl_attr_next(&attr, &type, &len, &data)) {
|
||||
switch (type) {
|
||||
case NL80211_ATTR_WDEV:
|
||||
if (len != 8)
|
||||
break;
|
||||
|
||||
wdev_id = data;
|
||||
break;
|
||||
|
||||
case NL80211_ATTR_IFINDEX:
|
||||
if (len != 4)
|
||||
break;
|
||||
|
||||
ifindex = data;
|
||||
break;
|
||||
|
||||
case NL80211_ATTR_FRAME:
|
||||
mpdu = mpdu_validate(data, len);
|
||||
if (!mpdu) {
|
||||
l_warn("Frame didn't validate as MMPDU");
|
||||
return;
|
||||
}
|
||||
|
||||
frame_len = len;
|
||||
break;
|
||||
|
||||
case NL80211_ATTR_RX_SIGNAL_DBM:
|
||||
if (len != 4)
|
||||
break;
|
||||
|
||||
rssi = *(const int32_t *) data;
|
||||
}
|
||||
}
|
||||
|
||||
if (!wdev_id || (group->wdev_id && group->wdev_id != *wdev_id)) {
|
||||
l_warn("Bad wdev attribute");
|
||||
return;
|
||||
}
|
||||
|
||||
if (!mpdu) {
|
||||
l_warn("Missing frame data");
|
||||
return;
|
||||
}
|
||||
|
||||
body = mmpdu_body(mpdu);
|
||||
|
||||
if (ifindex) {
|
||||
struct netdev *netdev = netdev_find(*ifindex);
|
||||
|
||||
if (netdev && memcmp(mpdu->address_1,
|
||||
netdev_get_address(netdev), 6) &&
|
||||
!util_is_broadcast_address(mpdu->address_1))
|
||||
return;
|
||||
}
|
||||
|
||||
/* Only match the frame type and subtype like the kernel does */
|
||||
#define FC_FTYPE_STYPE_MASK 0x00fc
|
||||
info.frame_type = l_get_le16(mpdu) & FC_FTYPE_STYPE_MASK;
|
||||
info.body = (const uint8_t *) body;
|
||||
info.body_len = (const uint8_t *) mpdu + frame_len - body;
|
||||
info.wdev_id = *wdev_id;
|
||||
|
||||
WATCHLIST_NOTIFY_MATCHES(&group->watches, frame_watch_match_prefix,
|
||||
&info, frame_watch_cb_t, mpdu,
|
||||
info.body, info.body_len, rssi);
|
||||
}
|
||||
|
||||
static void frame_watch_group_destroy(void *data)
|
||||
{
|
||||
struct watch_group *group = data;
|
||||
|
||||
if (group->unicast_watch_id)
|
||||
l_genl_remove_unicast_watch(group->genl,
|
||||
group->unicast_watch_id);
|
||||
|
||||
if (group->genl)
|
||||
l_genl_unref(group->genl);
|
||||
|
||||
if (group->nl80211)
|
||||
l_genl_family_free(group->nl80211);
|
||||
|
||||
watchlist_destroy(&group->watches);
|
||||
l_free(group);
|
||||
}
|
||||
|
||||
static void frame_watch_free(struct watchlist_item *item)
|
||||
{
|
||||
struct frame_watch *watch =
|
||||
l_container_of(item, struct frame_watch, super);
|
||||
|
||||
l_free(watch->prefix);
|
||||
l_free(watch);
|
||||
}
|
||||
|
||||
static const struct watchlist_ops frame_watch_ops = {
|
||||
.item_free = frame_watch_free,
|
||||
};
|
||||
|
||||
static struct watch_group *frame_watch_group_new(uint64_t wdev_id, uint32_t id)
|
||||
{
|
||||
struct watch_group *group = l_new(struct watch_group, 1);
|
||||
|
||||
group->id = id;
|
||||
group->wdev_id = wdev_id;
|
||||
watchlist_init(&group->watches, &frame_watch_ops);
|
||||
|
||||
if (id == 0)
|
||||
group->genl = l_genl_ref(iwd_get_genl());
|
||||
else {
|
||||
group->genl = l_genl_new();
|
||||
if (!group->genl)
|
||||
goto err;
|
||||
}
|
||||
|
||||
group->unicast_watch_id = l_genl_add_unicast_watch(group->genl,
|
||||
NL80211_GENL_NAME,
|
||||
frame_watch_unicast_notify,
|
||||
group, NULL);
|
||||
if (!group->unicast_watch_id) {
|
||||
l_error("Registering for unicast notification failed");
|
||||
goto err;
|
||||
}
|
||||
|
||||
group->nl80211 = l_genl_family_new(group->genl, NL80211_GENL_NAME);
|
||||
if (!group->nl80211) {
|
||||
l_error("Failed to obtain nl80211");
|
||||
goto err;
|
||||
}
|
||||
|
||||
return group;
|
||||
|
||||
err:
|
||||
frame_watch_group_destroy(group);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
static struct watch_group *frame_watch_group_get(uint64_t wdev_id, uint32_t id)
|
||||
{
|
||||
const struct l_queue_entry *entry;
|
||||
|
||||
for (entry = l_queue_get_entries(watch_groups); entry;
|
||||
entry = entry->next) {
|
||||
struct watch_group *group = entry->data;
|
||||
|
||||
if (group->id == id && (id == 0 || group->wdev_id == wdev_id))
|
||||
return group;
|
||||
}
|
||||
|
||||
return frame_watch_group_new(wdev_id, id);
|
||||
}
|
||||
|
||||
static void frame_watch_register_cb(struct l_genl_msg *msg, void *user_data)
|
||||
{
|
||||
if (l_genl_msg_get_error(msg) < 0)
|
||||
l_error("Could not register frame watch type %04x: %i",
|
||||
L_PTR_TO_UINT(user_data), l_genl_msg_get_error(msg));
|
||||
}
|
||||
|
||||
bool frame_watch_add(uint64_t wdev_id, uint32_t group_id, uint16_t frame_type,
|
||||
const uint8_t *prefix, size_t prefix_len,
|
||||
frame_watch_cb_t handler, void *user_data,
|
||||
frame_xchg_destroy_func_t destroy)
|
||||
{
|
||||
struct watch_group *group = frame_watch_group_get(wdev_id, group_id);
|
||||
struct frame_watch *watch;
|
||||
struct l_genl_msg *msg;
|
||||
struct frame_prefix_info info = { frame_type, prefix, prefix_len, wdev_id };
|
||||
bool registered;
|
||||
|
||||
if (!group)
|
||||
return false;
|
||||
|
||||
registered = l_queue_find(group->watches.items,
|
||||
frame_watch_match_prefix,
|
||||
&info);
|
||||
|
||||
watch = l_new(struct frame_watch, 1);
|
||||
watch->frame_type = frame_type;
|
||||
watch->prefix = prefix_len ? l_memdup(prefix, prefix_len) : NULL;
|
||||
watch->prefix_len = prefix_len;
|
||||
watch->wdev_id = wdev_id;
|
||||
watch->group = group;
|
||||
watchlist_link(&group->watches, &watch->super, handler, user_data,
|
||||
destroy);
|
||||
|
||||
if (registered)
|
||||
return true;
|
||||
|
||||
msg = l_genl_msg_new_sized(NL80211_CMD_REGISTER_FRAME, 32 + prefix_len);
|
||||
|
||||
l_genl_msg_append_attr(msg, NL80211_ATTR_WDEV, 8, &wdev_id);
|
||||
l_genl_msg_append_attr(msg, NL80211_ATTR_FRAME_TYPE, 2, &frame_type);
|
||||
l_genl_msg_append_attr(msg, NL80211_ATTR_FRAME_MATCH,
|
||||
prefix_len, prefix);
|
||||
|
||||
l_genl_family_send(group->nl80211, msg, frame_watch_register_cb,
|
||||
L_UINT_TO_PTR(frame_type), NULL);
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
static bool frame_watch_group_match(const void *a, const void *b)
|
||||
{
|
||||
const struct watch_group *group = a;
|
||||
uint32_t id = L_PTR_TO_UINT(b);
|
||||
|
||||
return group->id == id;
|
||||
}
|
||||
|
||||
bool frame_watch_group_remove(uint64_t wdev_id, uint32_t group_id)
|
||||
{
|
||||
struct watch_group *group = l_queue_remove_if(watch_groups,
|
||||
frame_watch_group_match,
|
||||
L_UINT_TO_PTR(group_id));
|
||||
|
||||
if (!group)
|
||||
return false;
|
||||
|
||||
frame_watch_group_destroy(group);
|
||||
return true;
|
||||
}
|
||||
|
||||
static bool frame_watch_item_remove_wdev(void *data, void *user_data)
|
||||
{
|
||||
struct frame_watch *watch =
|
||||
l_container_of(data, struct frame_watch, super);
|
||||
const uint64_t *wdev_id = user_data;
|
||||
|
||||
if (watch->wdev_id != *wdev_id)
|
||||
return false;
|
||||
|
||||
if (watch->super.destroy)
|
||||
watch->super.destroy(watch->super.notify_data);
|
||||
|
||||
frame_watch_free(&watch->super);
|
||||
return true;
|
||||
}
|
||||
|
||||
static bool frame_watch_group_remove_wdev(void *data, void *user_data)
|
||||
{
|
||||
struct watch_group *group = data;
|
||||
const uint64_t *wdev_id = user_data;
|
||||
|
||||
if (group->wdev_id == *wdev_id)
|
||||
return true;
|
||||
|
||||
if (group->id != 0)
|
||||
return false;
|
||||
|
||||
/*
|
||||
* Have to be careful here because we're messing with watchlist
|
||||
* internals.
|
||||
*/
|
||||
l_queue_foreach_remove(group->watches.items,
|
||||
frame_watch_item_remove_wdev,
|
||||
&wdev_id);
|
||||
return false;
|
||||
}
|
||||
|
||||
bool frame_watch_wdev_remove(uint64_t wdev_id)
|
||||
{
|
||||
return l_queue_foreach_remove(watch_groups, frame_watch_group_remove_wdev,
|
||||
&wdev_id) > 0;
|
||||
}
|
||||
|
||||
static bool frame_xchg_wdev_match(const void *a, const void *b)
|
||||
{
|
||||
const struct wdev_info *wdev = a;
|
||||
const uint64_t *id = b;
|
||||
|
||||
return wdev->id == *id;
|
||||
}
|
||||
|
||||
static void frame_xchg_config_notify(struct l_genl_msg *msg, void *user_data)
|
||||
{
|
||||
uint64_t wdev_id;
|
||||
uint32_t iftype;
|
||||
struct wdev_info *wdev;
|
||||
|
||||
switch (l_genl_msg_get_command(msg)) {
|
||||
case NL80211_CMD_NEW_INTERFACE:
|
||||
case NL80211_CMD_SET_INTERFACE:
|
||||
if (nl80211_parse_attrs(msg, NL80211_ATTR_WDEV, &wdev_id,
|
||||
NL80211_ATTR_IFTYPE, &iftype,
|
||||
NL80211_ATTR_UNSPEC) < 0)
|
||||
break;
|
||||
|
||||
wdev = l_queue_find(wdevs, frame_xchg_wdev_match, &wdev_id);
|
||||
|
||||
if (!wdev) {
|
||||
wdev = l_new(struct wdev_info, 1);
|
||||
wdev->id = wdev_id;
|
||||
wdev->iftype = iftype;
|
||||
|
||||
if (!wdevs)
|
||||
wdevs = l_queue_new();
|
||||
|
||||
l_queue_push_tail(wdevs, wdev);
|
||||
break;
|
||||
}
|
||||
|
||||
if (wdev->iftype != iftype) {
|
||||
wdev->iftype = iftype;
|
||||
frame_watch_wdev_remove(wdev_id);
|
||||
}
|
||||
|
||||
break;
|
||||
|
||||
case NL80211_CMD_DEL_INTERFACE:
|
||||
if (nl80211_parse_attrs(msg, NL80211_ATTR_WDEV, &wdev_id,
|
||||
NL80211_ATTR_UNSPEC) < 0)
|
||||
break;
|
||||
|
||||
wdev = l_queue_remove_if(wdevs, frame_xchg_wdev_match, &wdev_id);
|
||||
if (!wdev)
|
||||
break;
|
||||
|
||||
l_free(wdev);
|
||||
frame_watch_wdev_remove(wdev_id);
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
static int frame_xchg_init(void)
|
||||
{
|
||||
struct watch_group *default_group = frame_watch_group_new(0, 0);
|
||||
|
||||
if (!default_group)
|
||||
return -EIO;
|
||||
|
||||
if (!l_genl_family_register(default_group->nl80211, "config",
|
||||
frame_xchg_config_notify,
|
||||
NULL, NULL)) {
|
||||
l_error("Registering for config notifications failed");
|
||||
frame_watch_group_destroy(default_group);
|
||||
default_group = NULL;
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
watch_groups = l_queue_new();
|
||||
l_queue_push_tail(watch_groups, default_group);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void frame_xchg_exit(void)
|
||||
{
|
||||
l_queue_destroy(watch_groups, frame_watch_group_destroy);
|
||||
watch_groups = NULL;
|
||||
|
||||
l_queue_destroy(wdevs, l_free);
|
||||
wdevs = NULL;
|
||||
}
|
||||
|
||||
IWD_MODULE(frame_xchg, frame_xchg_init, frame_xchg_exit);
|
||||
|
|
@ -0,0 +1,35 @@
|
|||
/*
|
||||
*
|
||||
* Wireless daemon for Linux
|
||||
*
|
||||
* Copyright (C) 2020 Intel Corporation. All rights reserved.
|
||||
*
|
||||
* This library is free software; you can redistribute it and/or
|
||||
* modify it under the terms of the GNU Lesser General Public
|
||||
* License as published by the Free Software Foundation; either
|
||||
* version 2.1 of the License, or (at your option) any later version.
|
||||
*
|
||||
* This library is distributed in the hope that it will be useful,
|
||||
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
* Lesser General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU Lesser General Public
|
||||
* License along with this library; if not, write to the Free Software
|
||||
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
||||
*
|
||||
*/
|
||||
|
||||
struct mmpdu_header;
|
||||
|
||||
typedef void (*frame_watch_cb_t)(const struct mmpdu_header *frame,
|
||||
const void *body, size_t body_len,
|
||||
int rssi, void *user_data);
|
||||
typedef void (*frame_xchg_destroy_func_t)(void *user_data);
|
||||
|
||||
bool frame_watch_add(uint64_t wdev_id, uint32_t group, uint16_t frame_type,
|
||||
const uint8_t *prefix, size_t prefix_len,
|
||||
frame_watch_cb_t handler, void *user_data,
|
||||
frame_xchg_destroy_func_t destroy);
|
||||
bool frame_watch_group_remove(uint64_t wdev_id, uint32_t group);
|
||||
bool frame_watch_wdev_remove(uint64_t wdev_id);
|
||||
Loading…
Reference in New Issue