hostapd/wpa_supplicant/ibss_rsn.c

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/*
* wpa_supplicant - IBSS RSN
* Copyright (c) 2009-2013, Jouni Malinen <j@w1.fi>
*
* This software may be distributed under the terms of the BSD license.
* See README for more details.
*/
#include "includes.h"
#include "common.h"
#include "common/wpa_ctrl.h"
#include "utils/eloop.h"
#include "l2_packet/l2_packet.h"
#include "rsn_supp/wpa.h"
#include "rsn_supp/wpa_ie.h"
#include "ap/wpa_auth.h"
#include "wpa_supplicant_i.h"
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#include "driver_i.h"
#include "common/ieee802_11_defs.h"
#include "ibss_rsn.h"
static void ibss_rsn_auth_timeout(void *eloop_ctx, void *timeout_ctx);
static struct ibss_rsn_peer * ibss_rsn_get_peer(struct ibss_rsn *ibss_rsn,
const u8 *addr)
{
struct ibss_rsn_peer *peer;
for (peer = ibss_rsn->peers; peer; peer = peer->next)
if (os_memcmp(addr, peer->addr, ETH_ALEN) == 0)
break;
return peer;
}
static void ibss_rsn_free(struct ibss_rsn_peer *peer)
{
eloop_cancel_timeout(ibss_rsn_auth_timeout, peer, NULL);
wpa_auth_sta_deinit(peer->auth);
wpa_sm_deinit(peer->supp);
os_free(peer);
}
static void supp_set_state(void *ctx, enum wpa_states state)
{
struct ibss_rsn_peer *peer = ctx;
peer->supp_state = state;
}
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static enum wpa_states supp_get_state(void *ctx)
{
struct ibss_rsn_peer *peer = ctx;
return peer->supp_state;
}
static int supp_ether_send(void *ctx, const u8 *dest, u16 proto, const u8 *buf,
size_t len)
{
struct ibss_rsn_peer *peer = ctx;
struct wpa_supplicant *wpa_s = peer->ibss_rsn->wpa_s;
int encrypt = peer->authentication_status & IBSS_RSN_REPORTED_PTK;
wpa_printf(MSG_DEBUG, "SUPP: %s(dest=" MACSTR
" proto=0x%04x len=%lu no_encrypt=%d)",
__func__, MAC2STR(dest), proto, (unsigned long) len,
!encrypt);
wpa_supplicant: Send EAPOL frames over nl80211 where available Linux kernel v4.17 added the ability to request sending control port frames via nl80211 instead of a normal network socket. Doing this provides the device driver with ordering information between the control port frames and the installation of keys. This empowers it to avoid race conditions between, for example, PTK replacement and the sending of frame 4 of the 4-way rekeying handshake in an RSNA. The key difference between a TX_CONTROL_PORT and normal socket send is that the device driver will certainly get any EAPOL frames comprising a 4-way handshake before it gets the key installation call for the derived key. By flushing its TX buffers it can then ensure that no pending EAPOL frames are inadvertently encrypted with a key that the peer will not yet have installed. Update the RSN supplicant system to use this new operation for sending EAPOL-Key frames when the driver reports that this capability is available; otherwise, fall back to a normal Ethernet TX. I have tested this on DMG (11ad/ay) devices with an out-of-tree Linux driver that does not use mac80211. Without this patch I consistently see PTK rekeying fail if message 4/4 shares a stream with other in-flight traffic. With this patch, and the driver updated to flush the relevant TX queue before overwriting a PTK (knowing, now, that if there was a message 4/4 related to the key installation, it has already entered the driver queue), rekeying is reliable. There is still data loss surrounding key installation - this problem is alluded to in IEEE Std 802.11-2016, 12.6.21, where extended Key ID support is described as the eventual solution. This patch aims to at least prevent rekeying from totally breaking the association, in a way that works on kernels as far back as 4.17 (as per Alexander Wetzel extended Key ID support should be possible on 5.2). See http://lists.infradead.org/pipermail/hostap/2019-May/040089.html for a little more context. Signed-off-by: Brendan Jackman <brendan.jackman@bluwireless.co.uk>
2020-01-03 16:17:41 +01:00
if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_CONTROL_PORT)
return wpa_drv_tx_control_port(wpa_s, dest, proto, buf, len,
!encrypt);
wpa_supplicant: Send EAPOL frames over nl80211 where available Linux kernel v4.17 added the ability to request sending control port frames via nl80211 instead of a normal network socket. Doing this provides the device driver with ordering information between the control port frames and the installation of keys. This empowers it to avoid race conditions between, for example, PTK replacement and the sending of frame 4 of the 4-way rekeying handshake in an RSNA. The key difference between a TX_CONTROL_PORT and normal socket send is that the device driver will certainly get any EAPOL frames comprising a 4-way handshake before it gets the key installation call for the derived key. By flushing its TX buffers it can then ensure that no pending EAPOL frames are inadvertently encrypted with a key that the peer will not yet have installed. Update the RSN supplicant system to use this new operation for sending EAPOL-Key frames when the driver reports that this capability is available; otherwise, fall back to a normal Ethernet TX. I have tested this on DMG (11ad/ay) devices with an out-of-tree Linux driver that does not use mac80211. Without this patch I consistently see PTK rekeying fail if message 4/4 shares a stream with other in-flight traffic. With this patch, and the driver updated to flush the relevant TX queue before overwriting a PTK (knowing, now, that if there was a message 4/4 related to the key installation, it has already entered the driver queue), rekeying is reliable. There is still data loss surrounding key installation - this problem is alluded to in IEEE Std 802.11-2016, 12.6.21, where extended Key ID support is described as the eventual solution. This patch aims to at least prevent rekeying from totally breaking the association, in a way that works on kernels as far back as 4.17 (as per Alexander Wetzel extended Key ID support should be possible on 5.2). See http://lists.infradead.org/pipermail/hostap/2019-May/040089.html for a little more context. Signed-off-by: Brendan Jackman <brendan.jackman@bluwireless.co.uk>
2020-01-03 16:17:41 +01:00
if (wpa_s->l2)
return l2_packet_send(wpa_s->l2, dest, proto, buf, len);
return -1;
}
static u8 * supp_alloc_eapol(void *ctx, u8 type, const void *data,
u16 data_len, size_t *msg_len, void **data_pos)
{
struct ieee802_1x_hdr *hdr;
wpa_printf(MSG_DEBUG, "SUPP: %s(type=%d data_len=%d)",
__func__, type, data_len);
*msg_len = sizeof(*hdr) + data_len;
hdr = os_malloc(*msg_len);
if (hdr == NULL)
return NULL;
hdr->version = 2;
hdr->type = type;
hdr->length = host_to_be16(data_len);
if (data)
os_memcpy(hdr + 1, data, data_len);
else
os_memset(hdr + 1, 0, data_len);
if (data_pos)
*data_pos = hdr + 1;
return (u8 *) hdr;
}
static int supp_get_beacon_ie(void *ctx)
{
struct ibss_rsn_peer *peer = ctx;
wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
/* TODO: get correct RSN IE */
wpa_sm_set_ap_rsnxe(peer->supp, NULL, 0);
return wpa_sm_set_ap_rsn_ie(peer->supp,
(u8 *) "\x30\x14\x01\x00"
"\x00\x0f\xac\x04"
"\x01\x00\x00\x0f\xac\x04"
"\x01\x00\x00\x0f\xac\x02"
"\x00\x00", 22);
}
static void ibss_check_rsn_completed(struct ibss_rsn_peer *peer)
{
struct wpa_supplicant *wpa_s = peer->ibss_rsn->wpa_s;
if ((peer->authentication_status &
(IBSS_RSN_SET_PTK_SUPP | IBSS_RSN_SET_PTK_AUTH)) !=
(IBSS_RSN_SET_PTK_SUPP | IBSS_RSN_SET_PTK_AUTH))
return;
if (peer->authentication_status & IBSS_RSN_REPORTED_PTK)
return;
peer->authentication_status |= IBSS_RSN_REPORTED_PTK;
wpa_msg(wpa_s, MSG_INFO, IBSS_RSN_COMPLETED MACSTR,
MAC2STR(peer->addr));
}
static int supp_set_key(void *ctx, enum wpa_alg alg,
const u8 *addr, int key_idx, int set_tx,
const u8 *seq, size_t seq_len,
const u8 *key, size_t key_len)
{
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struct ibss_rsn_peer *peer = ctx;
wpa_printf(MSG_DEBUG, "SUPP: %s(alg=%d addr=" MACSTR " key_idx=%d "
"set_tx=%d)",
__func__, alg, MAC2STR(addr), key_idx, set_tx);
wpa_hexdump(MSG_DEBUG, "SUPP: set_key - seq", seq, seq_len);
wpa_hexdump_key(MSG_DEBUG, "SUPP: set_key - key", key, key_len);
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if (key_idx == 0) {
peer->authentication_status |= IBSS_RSN_SET_PTK_SUPP;
ibss_check_rsn_completed(peer);
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/*
* In IBSS RSN, the pairwise key from the 4-way handshake
* initiated by the peer with highest MAC address is used.
*/
if (os_memcmp(peer->ibss_rsn->wpa_s->own_addr, peer->addr,
ETH_ALEN) > 0) {
wpa_printf(MSG_DEBUG, "SUPP: Do not use this PTK");
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return 0;
}
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}
if (is_broadcast_ether_addr(addr))
addr = peer->addr;
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return wpa_drv_set_key(peer->ibss_rsn->wpa_s, alg, addr, key_idx,
set_tx, seq, seq_len, key, key_len);
}
static void * supp_get_network_ctx(void *ctx)
{
struct ibss_rsn_peer *peer = ctx;
return wpa_supplicant_get_ssid(peer->ibss_rsn->wpa_s);
}
static int supp_mlme_setprotection(void *ctx, const u8 *addr,
int protection_type, int key_type)
{
wpa_printf(MSG_DEBUG, "SUPP: %s(addr=" MACSTR " protection_type=%d "
"key_type=%d)",
__func__, MAC2STR(addr), protection_type, key_type);
return 0;
}
static void supp_cancel_auth_timeout(void *ctx)
{
wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
}
static void supp_deauthenticate(void * ctx, u16 reason_code)
{
wpa_printf(MSG_DEBUG, "SUPP: %s (TODO)", __func__);
}
static int ibss_rsn_supp_init(struct ibss_rsn_peer *peer, const u8 *own_addr,
const u8 *psk)
{
struct wpa_sm_ctx *ctx = os_zalloc(sizeof(*ctx));
if (ctx == NULL)
return -1;
ctx->ctx = peer;
ctx->msg_ctx = peer->ibss_rsn->wpa_s;
ctx->set_state = supp_set_state;
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ctx->get_state = supp_get_state;
ctx->ether_send = supp_ether_send;
ctx->get_beacon_ie = supp_get_beacon_ie;
ctx->alloc_eapol = supp_alloc_eapol;
ctx->set_key = supp_set_key;
ctx->get_network_ctx = supp_get_network_ctx;
ctx->mlme_setprotection = supp_mlme_setprotection;
ctx->cancel_auth_timeout = supp_cancel_auth_timeout;
ctx->deauthenticate = supp_deauthenticate;
peer->supp = wpa_sm_init(ctx);
if (peer->supp == NULL) {
wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_init() failed");
os_free(ctx);
return -1;
}
wpa_sm_set_own_addr(peer->supp, own_addr);
wpa_sm_set_param(peer->supp, WPA_PARAM_RSN_ENABLED, 1);
wpa_sm_set_param(peer->supp, WPA_PARAM_PROTO, WPA_PROTO_RSN);
wpa_sm_set_param(peer->supp, WPA_PARAM_PAIRWISE, WPA_CIPHER_CCMP);
wpa_sm_set_param(peer->supp, WPA_PARAM_GROUP, WPA_CIPHER_CCMP);
wpa_sm_set_param(peer->supp, WPA_PARAM_KEY_MGMT, WPA_KEY_MGMT_PSK);
wpa_sm_set_pmk(peer->supp, psk, PMK_LEN, NULL, NULL);
peer->supp_ie_len = sizeof(peer->supp_ie);
if (wpa_sm_set_assoc_wpa_ie_default(peer->supp, peer->supp_ie,
&peer->supp_ie_len) < 0) {
wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_set_assoc_wpa_ie_default()"
" failed");
return -1;
}
wpa_sm_notify_assoc(peer->supp, peer->addr);
return 0;
}
static void auth_logger(void *ctx, const u8 *addr, logger_level level,
const char *txt)
{
if (addr)
wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " - %s",
MAC2STR(addr), txt);
else
wpa_printf(MSG_DEBUG, "AUTH: %s", txt);
}
static const u8 * auth_get_psk(void *ctx, const u8 *addr,
const u8 *p2p_dev_addr, const u8 *prev_psk,
size_t *psk_len, int *vlan_id)
{
struct ibss_rsn *ibss_rsn = ctx;
if (psk_len)
*psk_len = PMK_LEN;
if (vlan_id)
*vlan_id = 0;
wpa_printf(MSG_DEBUG, "AUTH: %s (addr=" MACSTR " prev_psk=%p)",
__func__, MAC2STR(addr), prev_psk);
if (prev_psk)
return NULL;
return ibss_rsn->psk;
}
static int auth_send_eapol(void *ctx, const u8 *addr, const u8 *data,
size_t data_len, int encrypt)
{
struct ibss_rsn *ibss_rsn = ctx;
struct wpa_supplicant *wpa_s = ibss_rsn->wpa_s;
wpa_printf(MSG_DEBUG, "AUTH: %s(addr=" MACSTR " data_len=%lu "
"encrypt=%d)",
__func__, MAC2STR(addr), (unsigned long) data_len, encrypt);
if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_CONTROL_PORT)
return wpa_drv_tx_control_port(wpa_s, addr, ETH_P_EAPOL,
data, data_len, !encrypt);
if (wpa_s->l2)
return l2_packet_send(wpa_s->l2, addr, ETH_P_EAPOL, data,
data_len);
return -1;
}
static int auth_set_key(void *ctx, int vlan_id, enum wpa_alg alg,
const u8 *addr, int idx, u8 *key, size_t key_len)
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{
struct ibss_rsn *ibss_rsn = ctx;
u8 seq[6];
os_memset(seq, 0, sizeof(seq));
if (addr) {
wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d addr=" MACSTR
" key_idx=%d)",
__func__, alg, MAC2STR(addr), idx);
} else {
wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d key_idx=%d)",
__func__, alg, idx);
}
wpa_hexdump_key(MSG_DEBUG, "AUTH: set_key - key", key, key_len);
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if (idx == 0) {
if (addr) {
struct ibss_rsn_peer *peer;
peer = ibss_rsn_get_peer(ibss_rsn, addr);
if (peer) {
peer->authentication_status |=
IBSS_RSN_SET_PTK_AUTH;
ibss_check_rsn_completed(peer);
}
}
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/*
* In IBSS RSN, the pairwise key from the 4-way handshake
* initiated by the peer with highest MAC address is used.
*/
if (addr == NULL ||
os_memcmp(ibss_rsn->wpa_s->own_addr, addr, ETH_ALEN) < 0) {
wpa_printf(MSG_DEBUG, "AUTH: Do not use this PTK");
2009-01-17 17:14:41 +01:00
return 0;
}
2009-01-17 17:14:41 +01:00
}
return wpa_drv_set_key(ibss_rsn->wpa_s, alg, addr, idx,
1, seq, 6, key, key_len);
}
static void ibss_rsn_disconnect(void *ctx, const u8 *addr, u16 reason)
{
struct ibss_rsn *ibss_rsn = ctx;
wpa_drv_sta_deauth(ibss_rsn->wpa_s, addr, reason);
}
static int auth_for_each_sta(void *ctx, int (*cb)(struct wpa_state_machine *sm,
void *ctx),
void *cb_ctx)
{
struct ibss_rsn *ibss_rsn = ctx;
struct ibss_rsn_peer *peer;
wpa_printf(MSG_DEBUG, "AUTH: for_each_sta");
for (peer = ibss_rsn->peers; peer; peer = peer->next) {
if (peer->auth && cb(peer->auth, cb_ctx))
return 1;
}
return 0;
}
static void ibss_set_sta_authorized(struct ibss_rsn *ibss_rsn,
struct ibss_rsn_peer *peer, int authorized)
{
int res;
if (authorized) {
res = wpa_drv_sta_set_flags(ibss_rsn->wpa_s, peer->addr,
WPA_STA_AUTHORIZED,
WPA_STA_AUTHORIZED, ~0);
wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " authorizing port",
MAC2STR(peer->addr));
} else {
res = wpa_drv_sta_set_flags(ibss_rsn->wpa_s, peer->addr,
0, 0, ~WPA_STA_AUTHORIZED);
wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " unauthorizing port",
MAC2STR(peer->addr));
}
if (res && errno != ENOENT) {
wpa_printf(MSG_DEBUG, "Could not set station " MACSTR " flags "
"for kernel driver (errno=%d)",
MAC2STR(peer->addr), errno);
}
}
static void auth_set_eapol(void *ctx, const u8 *addr,
wpa_eapol_variable var, int value)
{
struct ibss_rsn *ibss_rsn = ctx;
struct ibss_rsn_peer *peer = ibss_rsn_get_peer(ibss_rsn, addr);
if (peer == NULL)
return;
switch (var) {
case WPA_EAPOL_authorized:
ibss_set_sta_authorized(ibss_rsn, peer, value);
break;
default:
/* do not handle any other event */
wpa_printf(MSG_DEBUG, "AUTH: eapol event not handled %d", var);
break;
}
}
static int ibss_rsn_auth_init_group(struct ibss_rsn *ibss_rsn,
const u8 *own_addr, struct wpa_ssid *ssid)
{
struct wpa_auth_config conf;
static const struct wpa_auth_callbacks cb = {
.logger = auth_logger,
.set_eapol = auth_set_eapol,
.send_eapol = auth_send_eapol,
.get_psk = auth_get_psk,
.set_key = auth_set_key,
.for_each_sta = auth_for_each_sta,
.disconnect = ibss_rsn_disconnect,
};
wpa_printf(MSG_DEBUG, "AUTH: Initializing group state machine");
os_memset(&conf, 0, sizeof(conf));
conf.wpa = 2;
conf.wpa_key_mgmt = WPA_KEY_MGMT_PSK;
conf.wpa_pairwise = WPA_CIPHER_CCMP;
conf.rsn_pairwise = WPA_CIPHER_CCMP;
conf.wpa_group = WPA_CIPHER_CCMP;
conf.eapol_version = 2;
conf.wpa_group_rekey = ssid->group_rekey ? ssid->group_rekey : 600;
conf.wpa_group_update_count = 4;
conf.wpa_pairwise_update_count = 4;
ibss_rsn->auth_group = wpa_init(own_addr, &conf, &cb, ibss_rsn);
if (ibss_rsn->auth_group == NULL) {
wpa_printf(MSG_DEBUG, "AUTH: wpa_init() failed");
return -1;
}
wpa_init_keys(ibss_rsn->auth_group);
return 0;
}
static int ibss_rsn_auth_init(struct ibss_rsn *ibss_rsn,
struct ibss_rsn_peer *peer)
{
peer->auth = wpa_auth_sta_init(ibss_rsn->auth_group, peer->addr, NULL);
if (peer->auth == NULL) {
wpa_printf(MSG_DEBUG, "AUTH: wpa_auth_sta_init() failed");
return -1;
}
/* TODO: get peer RSN IE with Probe Request */
if (wpa_validate_wpa_ie(ibss_rsn->auth_group, peer->auth, 0,
(u8 *) "\x30\x14\x01\x00"
"\x00\x0f\xac\x04"
"\x01\x00\x00\x0f\xac\x04"
"\x01\x00\x00\x0f\xac\x02"
"\x00\x00", 22, NULL, 0, NULL, 0, NULL, 0) !=
WPA_IE_OK) {
wpa_printf(MSG_DEBUG, "AUTH: wpa_validate_wpa_ie() failed");
return -1;
}
if (wpa_auth_sm_event(peer->auth, WPA_ASSOC))
return -1;
if (wpa_auth_sta_associated(ibss_rsn->auth_group, peer->auth))
return -1;
return 0;
}
static int ibss_rsn_send_auth(struct ibss_rsn *ibss_rsn, const u8 *da, int seq)
{
struct ieee80211_mgmt auth;
const size_t auth_length = IEEE80211_HDRLEN + sizeof(auth.u.auth);
struct wpa_supplicant *wpa_s = ibss_rsn->wpa_s;
os_memset(&auth, 0, sizeof(auth));
auth.frame_control = IEEE80211_FC(WLAN_FC_TYPE_MGMT,
WLAN_FC_STYPE_AUTH);
os_memcpy(auth.da, da, ETH_ALEN);
os_memcpy(auth.sa, wpa_s->own_addr, ETH_ALEN);
os_memcpy(auth.bssid, wpa_s->bssid, ETH_ALEN);
auth.u.auth.auth_alg = host_to_le16(WLAN_AUTH_OPEN);
auth.u.auth.auth_transaction = host_to_le16(seq);
auth.u.auth.status_code = host_to_le16(WLAN_STATUS_SUCCESS);
wpa_printf(MSG_DEBUG, "RSN: IBSS TX Auth frame (SEQ %d) to " MACSTR,
seq, MAC2STR(da));
return wpa_drv_send_mlme(wpa_s, (u8 *) &auth, auth_length, 0, 0);
}
static int ibss_rsn_is_auth_started(struct ibss_rsn_peer * peer)
{
return peer->authentication_status &
(IBSS_RSN_AUTH_BY_US | IBSS_RSN_AUTH_EAPOL_BY_US);
}
static struct ibss_rsn_peer *
ibss_rsn_peer_init(struct ibss_rsn *ibss_rsn, const u8 *addr)
{
struct ibss_rsn_peer *peer;
if (ibss_rsn == NULL)
return NULL;
peer = ibss_rsn_get_peer(ibss_rsn, addr);
if (peer) {
wpa_printf(MSG_DEBUG, "RSN: IBSS Supplicant for peer "MACSTR
" already running", MAC2STR(addr));
return peer;
}
wpa_printf(MSG_DEBUG, "RSN: Starting IBSS Supplicant for peer "MACSTR,
MAC2STR(addr));
peer = os_zalloc(sizeof(*peer));
if (peer == NULL) {
wpa_printf(MSG_DEBUG, "RSN: Could not allocate memory.");
return NULL;
}
peer->ibss_rsn = ibss_rsn;
os_memcpy(peer->addr, addr, ETH_ALEN);
peer->authentication_status = IBSS_RSN_AUTH_NOT_AUTHENTICATED;
if (ibss_rsn_supp_init(peer, ibss_rsn->wpa_s->own_addr,
ibss_rsn->psk) < 0) {
ibss_rsn_free(peer);
return NULL;
}
peer->next = ibss_rsn->peers;
ibss_rsn->peers = peer;
return peer;
}
static void ibss_rsn_auth_timeout(void *eloop_ctx, void *timeout_ctx)
{
struct ibss_rsn_peer *peer = eloop_ctx;
/*
* Assume peer does not support Authentication exchange or the frame was
* lost somewhere - start EAPOL Authenticator.
*/
wpa_printf(MSG_DEBUG,
"RSN: Timeout on waiting Authentication frame response from "
MACSTR " - start authenticator", MAC2STR(peer->addr));
peer->authentication_status |= IBSS_RSN_AUTH_BY_US;
ibss_rsn_auth_init(peer->ibss_rsn, peer);
}
int ibss_rsn_start(struct ibss_rsn *ibss_rsn, const u8 *addr)
{
struct ibss_rsn_peer *peer;
int res;
if (!ibss_rsn)
return -1;
/* if the peer already exists, exit immediately */
peer = ibss_rsn_get_peer(ibss_rsn, addr);
if (peer)
return 0;
peer = ibss_rsn_peer_init(ibss_rsn, addr);
if (peer == NULL)
return -1;
/* Open Authentication: send first Authentication frame */
res = ibss_rsn_send_auth(ibss_rsn, addr, 1);
if (res) {
/*
* The driver may not support Authentication frame exchange in
* IBSS. Ignore authentication and go through EAPOL exchange.
*/
peer->authentication_status |= IBSS_RSN_AUTH_BY_US;
return ibss_rsn_auth_init(ibss_rsn, peer);
} else {
os_get_reltime(&peer->own_auth_tx);
eloop_register_timeout(1, 0, ibss_rsn_auth_timeout, peer, NULL);
}
return 0;
}
static int ibss_rsn_peer_authenticated(struct ibss_rsn *ibss_rsn,
struct ibss_rsn_peer *peer, int reason)
{
int already_started;
if (ibss_rsn == NULL || peer == NULL)
return -1;
already_started = ibss_rsn_is_auth_started(peer);
peer->authentication_status |= reason;
if (already_started) {
wpa_printf(MSG_DEBUG, "RSN: IBSS Authenticator already "
"started for peer " MACSTR, MAC2STR(peer->addr));
return 0;
}
wpa_printf(MSG_DEBUG, "RSN: Starting IBSS Authenticator "
"for now-authenticated peer " MACSTR, MAC2STR(peer->addr));
return ibss_rsn_auth_init(ibss_rsn, peer);
}
void ibss_rsn_stop(struct ibss_rsn *ibss_rsn, const u8 *peermac)
{
struct ibss_rsn_peer *peer, *prev;
if (ibss_rsn == NULL)
return;
if (peermac == NULL) {
/* remove all peers */
wpa_printf(MSG_DEBUG, "%s: Remove all peers", __func__);
peer = ibss_rsn->peers;
while (peer) {
prev = peer;
peer = peer->next;
ibss_rsn_free(prev);
ibss_rsn->peers = peer;
}
} else {
/* remove specific peer */
wpa_printf(MSG_DEBUG, "%s: Remove specific peer " MACSTR,
__func__, MAC2STR(peermac));
for (prev = NULL, peer = ibss_rsn->peers; peer != NULL;
prev = peer, peer = peer->next) {
if (os_memcmp(peermac, peer->addr, ETH_ALEN) == 0) {
if (prev == NULL)
ibss_rsn->peers = peer->next;
else
prev->next = peer->next;
ibss_rsn_free(peer);
wpa_printf(MSG_DEBUG, "%s: Successfully "
"removed a specific peer",
__func__);
break;
}
}
}
}
struct ibss_rsn * ibss_rsn_init(struct wpa_supplicant *wpa_s,
struct wpa_ssid *ssid)
{
struct ibss_rsn *ibss_rsn;
ibss_rsn = os_zalloc(sizeof(*ibss_rsn));
if (ibss_rsn == NULL)
return NULL;
ibss_rsn->wpa_s = wpa_s;
if (ibss_rsn_auth_init_group(ibss_rsn, wpa_s->own_addr, ssid) < 0) {
ibss_rsn_deinit(ibss_rsn);
return NULL;
}
return ibss_rsn;
}
void ibss_rsn_deinit(struct ibss_rsn *ibss_rsn)
{
struct ibss_rsn_peer *peer, *prev;
if (ibss_rsn == NULL)
return;
peer = ibss_rsn->peers;
while (peer) {
prev = peer;
peer = peer->next;
ibss_rsn_free(prev);
}
if (ibss_rsn->auth_group)
wpa_deinit(ibss_rsn->auth_group);
os_free(ibss_rsn);
}
static int ibss_rsn_eapol_dst_supp(const u8 *buf, size_t len)
{
const struct ieee802_1x_hdr *hdr;
const struct wpa_eapol_key *key;
u16 key_info;
size_t plen;
/* TODO: Support other EAPOL packets than just EAPOL-Key */
if (len < sizeof(*hdr) + sizeof(*key))
return -1;
hdr = (const struct ieee802_1x_hdr *) buf;
key = (const struct wpa_eapol_key *) (hdr + 1);
plen = be_to_host16(hdr->length);
if (hdr->version < EAPOL_VERSION) {
/* TODO: backwards compatibility */
}
if (hdr->type != IEEE802_1X_TYPE_EAPOL_KEY) {
wpa_printf(MSG_DEBUG, "RSN: EAPOL frame (type %u) discarded, "
"not a Key frame", hdr->type);
return -1;
}
if (plen > len - sizeof(*hdr) || plen < sizeof(*key)) {
wpa_printf(MSG_DEBUG, "RSN: EAPOL frame payload size %lu "
"invalid (frame size %lu)",
(unsigned long) plen, (unsigned long) len);
return -1;
}
if (key->type != EAPOL_KEY_TYPE_RSN) {
wpa_printf(MSG_DEBUG, "RSN: EAPOL-Key type (%d) unknown, "
"discarded", key->type);
return -1;
}
key_info = WPA_GET_BE16(key->key_info);
return !!(key_info & WPA_KEY_INFO_ACK);
}
static int ibss_rsn_process_rx_eapol(struct ibss_rsn *ibss_rsn,
struct ibss_rsn_peer *peer,
const u8 *buf, size_t len)
{
int supp;
u8 *tmp;
supp = ibss_rsn_eapol_dst_supp(buf, len);
if (supp < 0)
return -1;
tmp = os_memdup(buf, len);
if (tmp == NULL)
return -1;
if (supp) {
peer->authentication_status |= IBSS_RSN_AUTH_EAPOL_BY_PEER;
wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Supplicant from "
MACSTR, MAC2STR(peer->addr));
wpa_sm_rx_eapol(peer->supp, peer->addr, tmp, len);
} else {
if (ibss_rsn_is_auth_started(peer) == 0) {
wpa_printf(MSG_DEBUG, "RSN: IBSS EAPOL for "
"Authenticator dropped as " MACSTR " is not "
"authenticated", MAC2STR(peer->addr));
os_free(tmp);
return -1;
}
wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Authenticator "
"from "MACSTR, MAC2STR(peer->addr));
wpa_receive(ibss_rsn->auth_group, peer->auth, tmp, len);
}
os_free(tmp);
return 1;
}
int ibss_rsn_rx_eapol(struct ibss_rsn *ibss_rsn, const u8 *src_addr,
const u8 *buf, size_t len)
{
struct ibss_rsn_peer *peer;
if (ibss_rsn == NULL)
return -1;
peer = ibss_rsn_get_peer(ibss_rsn, src_addr);
if (peer)
return ibss_rsn_process_rx_eapol(ibss_rsn, peer, buf, len);
if (ibss_rsn_eapol_dst_supp(buf, len) > 0) {
/*
* Create new IBSS peer based on an EAPOL message from the peer
* Authenticator.
*/
peer = ibss_rsn_peer_init(ibss_rsn, src_addr);
if (peer == NULL)
return -1;
/* assume the peer is authenticated already */
wpa_printf(MSG_DEBUG, "RSN: IBSS Not using IBSS Auth for peer "
MACSTR, MAC2STR(src_addr));
ibss_rsn_peer_authenticated(ibss_rsn, peer,
IBSS_RSN_AUTH_EAPOL_BY_US);
return ibss_rsn_process_rx_eapol(ibss_rsn, ibss_rsn->peers,
buf, len);
}
return 0;
}
void ibss_rsn_set_psk(struct ibss_rsn *ibss_rsn, const u8 *psk)
{
if (ibss_rsn == NULL)
return;
os_memcpy(ibss_rsn->psk, psk, PMK_LEN);
}
static void ibss_rsn_handle_auth_1_of_2(struct ibss_rsn *ibss_rsn,
struct ibss_rsn_peer *peer,
const u8* addr)
{
wpa_printf(MSG_DEBUG, "RSN: IBSS RX Auth frame (SEQ 1) from " MACSTR,
MAC2STR(addr));
if (peer &&
peer->authentication_status & (IBSS_RSN_SET_PTK_SUPP |
IBSS_RSN_SET_PTK_AUTH)) {
/* Clear the TK for this pair to allow recovery from the case
* where the peer STA has restarted and lost its key while we
* still have a pairwise key configured. */
wpa_printf(MSG_DEBUG, "RSN: Clear pairwise key for peer "
MACSTR, MAC2STR(addr));
wpa_drv_set_key(ibss_rsn->wpa_s, WPA_ALG_NONE, addr, 0, 0,
NULL, 0, NULL, 0);
}
if (peer &&
peer->authentication_status & IBSS_RSN_AUTH_EAPOL_BY_PEER) {
if (peer->own_auth_tx.sec) {
struct os_reltime now, diff;
os_get_reltime(&now);
os_reltime_sub(&now, &peer->own_auth_tx, &diff);
if (diff.sec == 0 && diff.usec < 500000) {
wpa_printf(MSG_DEBUG, "RSN: Skip IBSS reinit since only %u usec from own Auth frame TX",
(int) diff.usec);
goto skip_reinit;
}
}
/*
* A peer sent us an Authentication frame even though it already
* started an EAPOL session. We should reinit state machines
* here, but it's much more complicated than just deleting and
* recreating the state machine
*/
wpa_printf(MSG_DEBUG, "RSN: IBSS Reinitializing station "
MACSTR, MAC2STR(addr));
ibss_rsn_stop(ibss_rsn, addr);
peer = NULL;
}
if (!peer) {
peer = ibss_rsn_peer_init(ibss_rsn, addr);
if (!peer)
return;
wpa_printf(MSG_DEBUG, "RSN: IBSS Auth started by peer " MACSTR,
MAC2STR(addr));
}
skip_reinit:
/* reply with an Authentication frame now, before sending an EAPOL */
ibss_rsn_send_auth(ibss_rsn, addr, 2);
/* no need to start another AUTH challenge in the other way.. */
ibss_rsn_peer_authenticated(ibss_rsn, peer, IBSS_RSN_AUTH_EAPOL_BY_US);
}
void ibss_rsn_handle_auth(struct ibss_rsn *ibss_rsn, const u8 *auth_frame,
size_t len)
{
const struct ieee80211_mgmt *header;
struct ibss_rsn_peer *peer;
size_t auth_length;
header = (const struct ieee80211_mgmt *) auth_frame;
auth_length = IEEE80211_HDRLEN + sizeof(header->u.auth);
if (ibss_rsn == NULL || len < auth_length)
return;
if (le_to_host16(header->u.auth.auth_alg) != WLAN_AUTH_OPEN ||
le_to_host16(header->u.auth.status_code) != WLAN_STATUS_SUCCESS)
return;
peer = ibss_rsn_get_peer(ibss_rsn, header->sa);
switch (le_to_host16(header->u.auth.auth_transaction)) {
case 1:
ibss_rsn_handle_auth_1_of_2(ibss_rsn, peer, header->sa);
break;
case 2:
wpa_printf(MSG_DEBUG, "RSN: IBSS RX Auth frame (SEQ 2) from "
MACSTR, MAC2STR(header->sa));
if (!peer) {
wpa_printf(MSG_DEBUG, "RSN: Received Auth seq 2 from "
"unknown STA " MACSTR, MAC2STR(header->sa));
break;
}
/* authentication has been completed */
eloop_cancel_timeout(ibss_rsn_auth_timeout, peer, NULL);
wpa_printf(MSG_DEBUG, "RSN: IBSS Auth completed with " MACSTR,
MAC2STR(header->sa));
ibss_rsn_peer_authenticated(ibss_rsn, peer,
IBSS_RSN_AUTH_BY_US);
break;
}
}