Kernel/iwd
3
0
Fork 0
mirror of https://git.kernel.org/pub/scm/network/wireless/iwd.git synced 2024-12-22 21:22:37 +01:00
Code Releases Activity

ap: Send PTK handshake frame 1 of 4

Browse Source
This commit is contained in:
Andrew Zaborowski 2017-09-22 05:06:41 +02:00 committed by Denis Kenzior
parent 89c2f14683
commit c505de3582
1 changed files with 111 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

112
src/ap.c
View File

@ -40,6 +40,8 @@
#include "src/ie.h"
#include "src/mpdu.h"
#include "src/util.h"
#include "src/eapol.h"
#include "src/handshake.h"
#include "src/ap.h"
struct ap_state {
@ -54,6 +56,7 @@ struct ap_state {
uint8_t pmk[32];
struct l_queue *frame_watch_ids;
uint32_t start_stop_cmd_id;
uint32_t eapol_watch_id;
uint16_t last_aid;
struct l_queue *sta_states;
@ -70,6 +73,12 @@ struct sta_state {
struct ap_state *ap;
uint8_t *assoc_rsne;
size_t assoc_rsne_len;
uint64_t key_replay_counter;
uint8_t anonce[32];
uint8_t snonce[32];
uint8_t ptk[64];
bool have_anonce : 1;
bool ptk_complete : 1;
};
static struct l_genl_family *nl80211 = NULL;
@ -112,6 +121,8 @@ static void ap_free(void *data)
if (ap->start_stop_cmd_id)
l_genl_family_cancel(nl80211, ap->start_stop_cmd_id);
eapol_frame_watch_remove(ap->eapol_watch_id);
l_queue_destroy(ap->sta_states, ap_sta_free);
if (ap->rates)
@ -149,6 +160,99 @@ static void ap_set_rsn_info(struct ap_state *ap, struct ie_rsn_info *rsn)
rsn->group_cipher = IE_RSN_CIPHER_SUITE_NO_GROUP_TRAFFIC;
}
/* 802.11-2016 Section 12.7.6.2 */
static void ap_send_ptk_1_of_4(struct ap_state *ap, struct sta_state *sta)
{
uint32_t ifindex = device_get_ifindex(ap->device);
const uint8_t *aa = device_get_address(ap->device);
uint8_t frame_buf[512];
struct eapol_key *ek = (struct eapol_key *) frame_buf;
enum crypto_cipher cipher = ie_rsn_cipher_suite_to_cipher(ap->ciphers);
uint8_t pmkid[16];
if (!l_getrandom(sta->anonce, 32)) {
l_error("l_getrandom failed");
return;
}
sta->have_anonce = true;
sta->ptk_complete = false;
sta->key_replay_counter++;
memset(ek, 0, sizeof(struct eapol_key));
ek->header.protocol_version = EAPOL_PROTOCOL_VERSION_2004;
ek->header.packet_type = 0x3;
ek->descriptor_type = EAPOL_DESCRIPTOR_TYPE_80211;
/* Must be HMAC-SHA1-128 + AES when using CCMP with PSK or 8021X */
ek->key_descriptor_version = EAPOL_KEY_DESCRIPTOR_VERSION_HMAC_SHA1_AES;
ek->key_type = true;
ek->key_ack = true;
ek->key_length = L_CPU_TO_BE16(crypto_cipher_key_len(cipher));
ek->key_replay_counter = L_CPU_TO_BE64(sta->key_replay_counter);
memcpy(ek->key_nonce, sta->anonce, sizeof(ek->key_nonce));
/* Write the PMKID KDE into Key Data field unencrypted */
crypto_derive_pmkid(ap->pmk, sta->addr, aa, pmkid, false);
eapol_key_data_append(ek, HANDSHAKE_KDE_PMKID, pmkid, 16);
ek->header.packet_len = L_CPU_TO_BE16(sizeof(struct eapol_key) +
L_BE16_TO_CPU(ek->key_data_len) - 4);
eapol_tx_frame(ifindex, ETH_P_PAE, sta->addr,
(struct eapol_frame *) ek);
}
static void ap_eapol_key_handle(struct sta_state *sta,
const struct eapol_frame *frame)
{
size_t frame_len = 4 + L_BE16_TO_CPU(frame->header.packet_len);
const struct eapol_key *ek = eapol_key_validate((const void *) frame,
frame_len);
if (!ek)
return;
if (ek->request)
return; /* Not supported */
if (!sta->have_anonce)
return; /* Not expecting an EAPoL-Key yet */
}
static void ap_eapol_rx(uint16_t proto, const uint8_t *from,
const struct eapol_frame *frame, void *user_data)
{
struct ap_state *ap = user_data;
struct sta_state *sta;
l_debug("");
if (proto != ETH_P_PAE) {
l_error("AP data frame of unknown protocol %04x from %s",
proto, util_address_to_string(from));
return;
}
sta = l_queue_find(ap->sta_states, ap_sta_match_addr, from);
if (!sta || !sta->associated) {
l_error("AP EAPoL from disassociated STA %s",
util_address_to_string(from));
return;
}
switch (frame->header.packet_type) {
case 3: /* EAPoL-Key */
ap_eapol_key_handle(sta, frame);
break;
default:
l_error("AP received unknown packet type %i from %s",
frame->header.packet_type,
util_address_to_string(from));
break;
}
}
/*
* Build a Beacon frame or a Probe Response frame's header and body until
* the TIM IE. Except for the optional TIM IE which is inserted by the
@ -261,13 +365,15 @@ static uint32_t ap_send_mgmt_frame(struct ap_state *ap,
static void ap_new_sta_cb(struct l_genl_msg *msg, void *user_data)
{
struct sta_state *sta = 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 */
ap_send_ptk_1_of_4(sta->ap, sta);
}
static void ap_associate_sta(struct ap_state *ap, struct sta_state *sta)
@ -292,6 +398,7 @@ static void ap_associate_sta(struct ap_state *ap, struct sta_state *sta)
uint16_t capability = l_get_le16(&sta->capability);
sta->associated = true;
sta->key_replay_counter = 0;
minr = l_uintset_find_min(sta->rates);
maxr = l_uintset_find_max(sta->rates);
@ -968,6 +1075,7 @@ int ap_start(struct device *device, const char *ssid, const char *psk,
{
struct netdev *netdev = device_get_netdev(device);
struct wiphy *wiphy = device_get_wiphy(device);
uint32_t ifindex = device_get_ifindex(device);
struct ap_state *ap;
struct l_genl_msg *cmd;
const struct l_queue_entry *entry;
@ -1034,6 +1142,8 @@ int ap_start(struct device *device, const char *ssid, const char *psk,
goto error;
}
ap->eapol_watch_id = eapol_frame_watch_add(ifindex, ap_eapol_rx, ap);
if (!ap_list)
ap_list = l_queue_new();