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mirror of https://git.kernel.org/pub/scm/network/wireless/iwd.git synced 2024-12-23 06:02:37 +01:00

ap: Handle Association / Disassociation

Parse Association Request frames and send Association Responses, handle
Disassociation.  With this we should be able to receive uncontrolled
port data frames since we register the STAs with the kernel.

In this version I don't register for Reassociation frames.
This commit is contained in:
Andrew Zaborowski 2017-09-22 05:06:39 +02:00 committed by Denis Kenzior
parent 1842fe542b
commit 29ee350ec3

414
src/ap.c
View File

@ -51,14 +51,25 @@ struct ap_state {
unsigned int ciphers;
uint32_t beacon_interval;
struct l_uintset *rates;
uint8_t pmk[32];
struct l_queue *frame_watch_ids;
uint32_t start_stop_cmd_id;
uint16_t last_aid;
struct l_queue *sta_states;
};
struct sta_state {
uint8_t addr[6];
bool associated;
uint16_t aid;
struct mmpdu_field_capability capability;
uint16_t listen_interval;
struct l_uintset *rates;
uint32_t assoc_resp_cmd_id;
struct ap_state *ap;
uint8_t *assoc_rsne;
size_t assoc_rsne_len;
};
static struct l_genl_family *nl80211 = NULL;
@ -69,6 +80,12 @@ static void ap_sta_free(void *data)
{
struct sta_state *sta = data;
l_uintset_free(sta->rates);
l_free(sta->assoc_rsne);
if (sta->assoc_resp_cmd_id)
l_genl_family_cancel(nl80211, sta->assoc_resp_cmd_id);
l_free(sta);
}
@ -110,6 +127,18 @@ static bool ap_sta_match_addr(const void *a, const void *b)
return !memcmp(sta->addr, b, 6);
}
static void ap_del_sta_cb(struct l_genl_msg *msg, void *user_data)
{
if (l_genl_msg_get_error(msg) < 0)
l_error("DEL_STATION failed: %i", l_genl_msg_get_error(msg));
}
static void ap_del_key_cb(struct l_genl_msg *msg, void *user_data)
{
if (l_genl_msg_get_error(msg) < 0)
l_debug("DEL_KEY failed: %i", l_genl_msg_get_error(msg));
}
#define CIPHER_SUITE_GROUP_NOT_ALLOWED 0x000fac07
static void ap_set_rsn_info(struct ap_state *ap, struct ie_rsn_info *rsn)
@ -230,6 +259,340 @@ static uint32_t ap_send_mgmt_frame(struct ap_state *ap,
return id;
}
static void ap_new_sta_cb(struct l_genl_msg *msg, void *user_data)
{
if (l_genl_msg_get_error(msg) < 0) {
l_error("NEW_STATION failed: %i", l_genl_msg_get_error(msg));
return;
}
/* TODO: retry counters and timers */
/* TODO: send 4-Way Handshake frame 1/4 */
}
static void ap_associate_sta(struct ap_state *ap, struct sta_state *sta)
{
struct l_genl_msg *msg;
uint32_t ifindex = device_get_ifindex(ap->device);
/*
* This should hopefully work both with and without
* NL80211_FEATURE_FULL_AP_CLIENT_STATE.
*/
struct nl80211_sta_flag_update flags = {
.mask = (1 << NL80211_STA_FLAG_AUTHENTICATED) |
(1 << NL80211_STA_FLAG_ASSOCIATED) |
(1 << NL80211_STA_FLAG_AUTHORIZED) |
(1 << NL80211_STA_FLAG_MFP),
.set = (1 << NL80211_STA_FLAG_AUTHENTICATED) |
(1 << NL80211_STA_FLAG_ASSOCIATED),
};
uint8_t key_id = 0;
uint8_t rates[256];
uint32_t r, minr, maxr, count = 0;
uint16_t capability = l_get_le16(&sta->capability);
sta->associated = true;
minr = l_uintset_find_min(sta->rates);
maxr = l_uintset_find_max(sta->rates);
for (r = minr; r <= maxr; r++)
if (l_uintset_contains(sta->rates, r))
rates[count++] = r;
msg = l_genl_msg_new_sized(NL80211_CMD_NEW_STATION, 300);
l_genl_msg_append_attr(msg, NL80211_ATTR_IFINDEX, 4, &ifindex);
l_genl_msg_append_attr(msg, NL80211_ATTR_MAC, 6, sta->addr);
l_genl_msg_append_attr(msg, NL80211_ATTR_STA_AID, 2, &sta->aid);
l_genl_msg_append_attr(msg, NL80211_ATTR_STA_FLAGS2, 8, &flags);
l_genl_msg_append_attr(msg, NL80211_ATTR_STA_SUPPORTED_RATES,
count, &rates);
l_genl_msg_append_attr(msg, NL80211_ATTR_STA_LISTEN_INTERVAL, 2,
&sta->listen_interval);
l_genl_msg_append_attr(msg, NL80211_ATTR_STA_CAPABILITY, 2,
&capability);
if (!l_genl_family_send(nl80211, msg, ap_new_sta_cb, sta, NULL)) {
l_genl_msg_unref(msg);
l_error("Issuing NEW_STATION failed");
}
msg = l_genl_msg_new_sized(NL80211_CMD_DEL_KEY, 64);
l_genl_msg_append_attr(msg, NL80211_ATTR_IFINDEX, 4, &ifindex);
l_genl_msg_append_attr(msg, NL80211_ATTR_KEY_IDX, 1, &key_id);
l_genl_msg_append_attr(msg, NL80211_ATTR_MAC, 6, sta->addr);
if (!l_genl_family_send(nl80211, msg, ap_del_key_cb, NULL, NULL)) {
l_genl_msg_unref(msg);
l_error("Issuing DEL_KEY failed");
}
}
static void ap_disassociate_sta(struct ap_state *ap, struct sta_state *sta)
{
struct l_genl_msg *msg;
uint32_t ifindex = device_get_ifindex(ap->device);
uint8_t key_id = 0;
sta->associated = false;
msg = l_genl_msg_new_sized(NL80211_CMD_DEL_STATION, 64);
l_genl_msg_append_attr(msg, NL80211_ATTR_IFINDEX, 4, &ifindex);
l_genl_msg_append_attr(msg, NL80211_ATTR_MAC, 6, sta->addr);
l_genl_msg_append_attr(msg, NL80211_ATTR_STA_AID, 2, &sta->aid);
if (!l_genl_family_send(nl80211, msg, ap_del_sta_cb, NULL, NULL)) {
l_genl_msg_unref(msg);
l_error("Issuing DEL_STATION failed");
}
msg = l_genl_msg_new_sized(NL80211_CMD_DEL_KEY, 64);
l_genl_msg_append_attr(msg, NL80211_ATTR_IFINDEX, 4, &ifindex);
l_genl_msg_append_attr(msg, NL80211_ATTR_KEY_IDX, 1, &key_id);
l_genl_msg_append_attr(msg, NL80211_ATTR_MAC, 6, sta->addr);
if (!l_genl_family_send(nl80211, msg, ap_del_key_cb, NULL, NULL)) {
l_genl_msg_unref(msg);
l_error("Issuing DEL_KEY failed");
}
}
static bool ap_common_rates(struct l_uintset *ap_rates,
struct l_uintset *sta_rates)
{
uint32_t r, minr, maxr;
minr = l_uintset_find_min(ap_rates);
maxr = l_uintset_find_max(ap_rates);
/* Our lowest rate is a Basic Rate so must be supported */
if (!l_uintset_contains(sta_rates, minr))
return false;
for (r = minr + 1; r <= maxr; r++)
if (l_uintset_contains(ap_rates, r) &&
l_uintset_contains(sta_rates, r))
return true;
return false;
}
static void ap_success_assoc_resp_cb(struct l_genl_msg *msg, void *user_data)
{
struct sta_state *sta = user_data;
struct ap_state *ap = sta->ap;
sta->assoc_resp_cmd_id = 0;
if (l_genl_msg_get_error(msg) < 0) {
l_error("AP Association Response not sent or not ACKed: %i",
l_genl_msg_get_error(msg));
/* If we were in State 3 or 4 go to back to State 2 */
if (sta->associated)
ap_disassociate_sta(ap, sta);
return;
}
/* If we were in State 2 also go to State 3 */
if (!sta->associated)
ap_associate_sta(ap, sta);
l_info("AP Association Response ACK received");
}
static void ap_fail_assoc_resp_cb(struct l_genl_msg *msg, void *user_data)
{
if (l_genl_msg_get_error(msg) < 0)
l_error("AP Association Response with an error status not "
"sent or not ACKed: %i", l_genl_msg_get_error(msg));
else
l_info("AP Association Response with an errror status "
"delivered OK");
}
static uint32_t ap_assoc_resp(struct ap_state *ap, struct sta_state *sta,
const uint8_t *dest, uint16_t aid,
enum mmpdu_reason_code status_code,
l_genl_msg_func_t callback)
{
const uint8_t *addr = device_get_address(ap->device);
uint8_t mpdu_buf[128];
struct mmpdu_header *mpdu = (void *) mpdu_buf;
struct mmpdu_association_response *resp;
size_t ies_len = 0;
uint16_t capability = IE_BSS_CAP_ESS | IE_BSS_CAP_PRIVACY;
uint32_t r, minr, maxr, count;
memset(mpdu, 0, sizeof(*mpdu));
/* Header */
mpdu->fc.protocol_version = 0;
mpdu->fc.type = MPDU_TYPE_MANAGEMENT;
mpdu->fc.subtype = MPDU_MANAGEMENT_SUBTYPE_ASSOCIATION_RESPONSE;
memcpy(mpdu->address_1, dest, 6); /* DA */
memcpy(mpdu->address_2, addr, 6); /* SA */
memcpy(mpdu->address_3, addr, 6); /* BSSID */
/* Association Response body */
resp = (void *) mmpdu_body(mpdu);
l_put_le16(capability, &resp->capability);
resp->status_code = L_CPU_TO_LE16(status_code);
resp->aid = L_CPU_TO_LE16(aid | 0xc000);
/* Supported Rates IE */
resp->ies[ies_len++] = IE_TYPE_SUPPORTED_RATES;
minr = l_uintset_find_min(ap->rates);
maxr = l_uintset_find_max(ap->rates);
count = 0;
for (r = minr; r <= maxr && count < 8; r++)
if (l_uintset_contains(ap->rates, r)) {
uint8_t flag = 0;
/* Mark only the lowest rate as Basic Rate */
if (count == 0)
flag = 0x80;
resp->ies[ies_len + 1 + count++] = r | flag;
}
resp->ies[ies_len++] = count;
ies_len += count;
return ap_send_mgmt_frame(ap, mpdu, resp->ies + ies_len - mpdu_buf,
true, callback, sta);
}
/* 802.11-2016 9.3.3.6 (frame format), 802.11-2016 11.3.5.3 (MLME/SME) */
static void ap_assoc_req_cb(struct netdev *netdev,
const struct mmpdu_header *hdr,
const void *body, size_t body_len,
void *user_data)
{
struct ap_state *ap = user_data;
struct sta_state *sta;
const uint8_t *from = hdr->address_2;
const struct mmpdu_association_request *req = body;
struct ie_tlv_iter iter;
const char *ssid = NULL;
const uint8_t *rsn = NULL;
size_t ssid_len = 0, rsn_len = 0;
struct l_uintset *rates = NULL;
struct ie_rsn_info rsn_info;
const uint8_t *bssid = device_get_address(ap->device);
int err;
l_info("AP Association Request from %s", util_address_to_string(from));
if (memcmp(hdr->address_1, bssid, 6) ||
memcmp(hdr->address_3, bssid, 6))
return;
sta = l_queue_find(ap->sta_states, ap_sta_match_addr, from);
if (!sta) {
err = MMPDU_REASON_CODE_STA_REQ_ASSOC_WITHOUT_AUTH;
goto bad_frame;
}
if (sta->assoc_resp_cmd_id)
return;
sta->capability = req->capability;
sta->listen_interval = L_LE16_TO_CPU(req->listen_interval);
ie_tlv_iter_init(&iter, req->ies, body_len - sizeof(*req));
while (ie_tlv_iter_next(&iter))
switch (ie_tlv_iter_get_tag(&iter)) {
case IE_TYPE_SSID:
ssid = (const char *) ie_tlv_iter_get_data(&iter);
ssid_len = ie_tlv_iter_get_length(&iter);
break;
case IE_TYPE_SUPPORTED_RATES:
case IE_TYPE_EXTENDED_SUPPORTED_RATES:
if (ie_parse_supported_rates(&iter, &rates) < 0) {
err = MMPDU_REASON_CODE_INVALID_IE;
goto bad_frame;
}
break;
case IE_TYPE_RSN:
if (ie_parse_rsne(&iter, &rsn_info) < 0) {
err = MMPDU_REASON_CODE_INVALID_IE;
goto bad_frame;
}
rsn = (const uint8_t *) ie_tlv_iter_get_data(&iter);
rsn_len = ie_tlv_iter_get_length(&iter);
break;
}
if (!rates || !ssid || !rsn || ssid_len != strlen(ap->ssid) ||
memcmp(ssid, ap->ssid, ssid_len)) {
err = MMPDU_REASON_CODE_INVALID_IE;
goto bad_frame;
}
if (sta->rates)
l_uintset_free(sta->rates);
sta->rates = rates;
if (!ap_common_rates(ap->rates, sta->rates)) {
err = MMPDU_REASON_CODE_UNSPECIFIED;
goto unsupported;
}
if (rsn_info.mfpr && rsn_info.spp_a_msdu_required) {
err = MMPDU_REASON_CODE_UNSPECIFIED;
goto unsupported;
}
if (!(rsn_info.pairwise_ciphers & ap->ciphers)) {
err = MMPDU_REASON_CODE_UNSPECIFIED;
goto unsupported;
}
if (rsn_info.akm_suites != IE_RSN_AKM_SUITE_PSK) {
err = MMPDU_REASON_CODE_UNSPECIFIED;
goto unsupported;
}
if (sta->assoc_rsne)
l_free(sta->assoc_rsne);
sta->assoc_rsne = l_memdup(rsn, rsn_len);
sta->assoc_rsne_len = rsn_len;
/*
* Everything fine so far, assign an AID, send response. According
* to 802.11-2016 11.3.5.3 l) we will only go to State 3
* (set sta->associated) once we receive the station's ACK or gave
* up on resends.
*/
sta->aid = ++ap->last_aid;
sta->assoc_resp_cmd_id = ap_assoc_resp(ap, sta, sta->addr, sta->aid, 0,
ap_success_assoc_resp_cb);
if (!sta->assoc_resp_cmd_id)
l_error("Sending success Association Response failed");
return;
unsupported:
bad_frame:
if (rates)
l_uintset_free(rates);
if (!ap_assoc_resp(ap, NULL, from, 0, err, ap_fail_assoc_resp_cb))
l_error("Sending error Association Response failed");
}
static void ap_probe_resp_cb(struct l_genl_msg *msg, void *user_data)
{
if (l_genl_msg_get_error(msg) < 0)
@ -335,6 +698,38 @@ static void ap_probe_req_cb(struct netdev *netdev,
ap_probe_resp_cb, NULL);
}
/* 802.11-2016 9.3.3.5 (frame format), 802.11-2016 11.3.5.9 (MLME/SME) */
static void ap_disassoc_cb(struct netdev *netdev,
const struct mmpdu_header *hdr,
const void *body, size_t body_len,
void *user_data)
{
struct ap_state *ap = user_data;
struct sta_state *sta;
const struct mmpdu_disassociation *disassoc = body;
const uint8_t *bssid = device_get_address(ap->device);
l_info("AP Disassociation from %s, reason %i",
util_address_to_string(hdr->address_2),
(int) L_LE16_TO_CPU(disassoc->reason_code));
if (memcmp(hdr->address_1, bssid, 6) ||
memcmp(hdr->address_3, bssid, 6))
return;
sta = l_queue_find(ap->sta_states, ap_sta_match_addr, hdr->address_2);
if (sta && sta->assoc_resp_cmd_id) {
l_genl_family_cancel(nl80211, sta->assoc_resp_cmd_id);
sta->assoc_resp_cmd_id = 0;
}
if (!sta || !sta->associated)
return;
ap_disassociate_sta(ap, sta);
}
static void ap_auth_reply_cb(struct l_genl_msg *msg, void *user_data)
{
if (l_genl_msg_get_error(msg) < 0)
@ -425,6 +820,7 @@ static void ap_auth_cb(struct netdev *netdev, const struct mmpdu_header *hdr,
*/
sta = l_new(struct sta_state, 1);
memcpy(sta->addr, from, 6);
sta->ap = ap;
if (!ap->sta_states)
ap->sta_states = l_queue_new();
@ -465,6 +861,14 @@ static void ap_deauth_cb(struct netdev *netdev, const struct mmpdu_header *hdr,
if (!sta)
return;
if (sta->assoc_resp_cmd_id) {
l_genl_family_cancel(nl80211, sta->assoc_resp_cmd_id);
sta->assoc_resp_cmd_id = 0;
}
if (sta->associated)
ap_disassociate_sta(ap, sta);
ap_sta_free(sta);
}
@ -589,11 +993,21 @@ int ap_start(struct device *device, const char *ssid, const char *psk,
l_uintset_put(ap->rates, 22); /* 11 Mbps*/
ap->frame_watch_ids = l_queue_new();
id = netdev_frame_watch_add(netdev, 0x0000 |
(MPDU_MANAGEMENT_SUBTYPE_ASSOCIATION_REQUEST << 4),
NULL, 0, ap_assoc_req_cb, ap);
l_queue_push_tail(ap->frame_watch_ids, L_UINT_TO_PTR(id));
id = netdev_frame_watch_add(netdev, 0x0000 |
(MPDU_MANAGEMENT_SUBTYPE_PROBE_REQUEST << 4),
NULL, 0, ap_probe_req_cb, ap);
l_queue_push_tail(ap->frame_watch_ids, L_UINT_TO_PTR(id));
id = netdev_frame_watch_add(netdev, 0x0000 |
(MPDU_MANAGEMENT_SUBTYPE_DISASSOCIATION << 4),
NULL, 0, ap_disassoc_cb, ap);
l_queue_push_tail(ap->frame_watch_ids, L_UINT_TO_PTR(id));
id = netdev_frame_watch_add(netdev, 0x0000 |
(MPDU_MANAGEMENT_SUBTYPE_AUTHENTICATION << 4),
NULL, 0, ap_auth_cb, ap);