hostapd/src/ap/peerkey_auth.c
Jouni Malinen 8492cc79c0 PeerKey: Remove dead code related to STSL negotiation state
The struct wpa_stsl_negotiation seemed to have been for some kind of
tracking of state of PeerKey negotiations within hostapd. However,
nothing is actually adding any entries to wpa_auth->stsl_negotiations or
using this state. Since PeerKey does not look like something that would
be deployed in practice, there is no justification to spend time on
making this any more complete. Remove the dead code now instead of
trying to figure out what it might be used for.

Signed-off-by: Jouni Malinen <j@w1.fi>
2017-02-12 11:15:49 +02:00

355 lines
9.6 KiB
C

/*
* hostapd - PeerKey for Direct Link Setup (DLS)
* Copyright (c) 2006-2009, Jouni Malinen <j@w1.fi>
*
* This software may be distributed under the terms of the BSD license.
* See README for more details.
*/
#include "utils/includes.h"
#include "utils/common.h"
#include "utils/eloop.h"
#include "crypto/sha1.h"
#include "crypto/sha256.h"
#include "crypto/random.h"
#include "wpa_auth.h"
#include "wpa_auth_i.h"
#include "wpa_auth_ie.h"
#ifdef CONFIG_PEERKEY
struct wpa_stsl_search {
const u8 *addr;
struct wpa_state_machine *sm;
};
static int wpa_stsl_select_sta(struct wpa_state_machine *sm, void *ctx)
{
struct wpa_stsl_search *search = ctx;
if (os_memcmp(search->addr, sm->addr, ETH_ALEN) == 0) {
search->sm = sm;
return 1;
}
return 0;
}
static void wpa_smk_send_error(struct wpa_authenticator *wpa_auth,
struct wpa_state_machine *sm, const u8 *peer,
u16 mui, u16 error_type)
{
u8 kde[2 + RSN_SELECTOR_LEN + ETH_ALEN +
2 + RSN_SELECTOR_LEN + sizeof(struct rsn_error_kde)];
u8 *pos;
struct rsn_error_kde error;
wpa_auth_logger(wpa_auth, sm->addr, LOGGER_DEBUG,
"Sending SMK Error");
pos = kde;
if (peer) {
pos = wpa_add_kde(pos, RSN_KEY_DATA_MAC_ADDR, peer, ETH_ALEN,
NULL, 0);
}
error.mui = host_to_be16(mui);
error.error_type = host_to_be16(error_type);
pos = wpa_add_kde(pos, RSN_KEY_DATA_ERROR,
(u8 *) &error, sizeof(error), NULL, 0);
__wpa_send_eapol(wpa_auth, sm,
WPA_KEY_INFO_SECURE | WPA_KEY_INFO_MIC |
WPA_KEY_INFO_SMK_MESSAGE | WPA_KEY_INFO_ERROR,
NULL, NULL, kde, pos - kde, 0, 0, 0);
}
void wpa_smk_m1(struct wpa_authenticator *wpa_auth,
struct wpa_state_machine *sm, struct wpa_eapol_key *key,
const u8 *key_data, size_t key_data_len)
{
struct wpa_eapol_ie_parse kde;
struct wpa_stsl_search search;
u8 *buf, *pos;
size_t buf_len;
if (wpa_parse_kde_ies(key_data, key_data_len, &kde) < 0) {
wpa_printf(MSG_INFO, "RSN: Failed to parse KDEs in SMK M1");
return;
}
if (kde.rsn_ie == NULL || kde.mac_addr == NULL ||
kde.mac_addr_len < ETH_ALEN) {
wpa_printf(MSG_INFO, "RSN: No RSN IE or MAC address KDE in "
"SMK M1");
return;
}
/* Initiator = sm->addr; Peer = kde.mac_addr */
search.addr = kde.mac_addr;
search.sm = NULL;
if (wpa_auth_for_each_sta(wpa_auth, wpa_stsl_select_sta, &search) ==
0 || search.sm == NULL) {
wpa_printf(MSG_DEBUG, "RSN: SMK handshake with " MACSTR
" aborted - STA not associated anymore",
MAC2STR(kde.mac_addr));
wpa_smk_send_error(wpa_auth, sm, kde.mac_addr, STK_MUI_SMK,
STK_ERR_STA_NR);
return;
}
buf_len = kde.rsn_ie_len + 2 + RSN_SELECTOR_LEN + ETH_ALEN;
buf = os_malloc(buf_len);
if (buf == NULL)
return;
/* Initiator RSN IE */
os_memcpy(buf, kde.rsn_ie, kde.rsn_ie_len);
pos = buf + kde.rsn_ie_len;
/* Initiator MAC Address */
pos = wpa_add_kde(pos, RSN_KEY_DATA_MAC_ADDR, sm->addr, ETH_ALEN,
NULL, 0);
/* SMK M2:
* EAPOL-Key(S=1, M=1, A=1, I=0, K=0, SM=1, KeyRSC=0, Nonce=INonce,
* MIC=MIC, DataKDs=(RSNIE_I, MAC_I KDE)
*/
wpa_auth_logger(wpa_auth, search.sm->addr, LOGGER_DEBUG,
"Sending SMK M2");
__wpa_send_eapol(wpa_auth, search.sm,
WPA_KEY_INFO_SECURE | WPA_KEY_INFO_MIC |
WPA_KEY_INFO_ACK | WPA_KEY_INFO_SMK_MESSAGE,
NULL, key->key_nonce, buf, pos - buf, 0, 0, 0);
os_free(buf);
}
static void wpa_send_smk_m4(struct wpa_authenticator *wpa_auth,
struct wpa_state_machine *sm,
struct wpa_eapol_key *key,
struct wpa_eapol_ie_parse *kde,
const u8 *smk)
{
u8 *buf, *pos;
size_t buf_len;
u32 lifetime;
/* SMK M4:
* EAPOL-Key(S=1, M=1, A=0, I=1, K=0, SM=1, KeyRSC=0, Nonce=PNonce,
* MIC=MIC, DataKDs=(MAC_I KDE, INonce KDE, SMK KDE,
* Lifetime KDE)
*/
buf_len = 2 + RSN_SELECTOR_LEN + ETH_ALEN +
2 + RSN_SELECTOR_LEN + WPA_NONCE_LEN +
2 + RSN_SELECTOR_LEN + PMK_LEN + WPA_NONCE_LEN +
2 + RSN_SELECTOR_LEN + sizeof(lifetime);
pos = buf = os_malloc(buf_len);
if (buf == NULL)
return;
/* Initiator MAC Address */
pos = wpa_add_kde(pos, RSN_KEY_DATA_MAC_ADDR, kde->mac_addr, ETH_ALEN,
NULL, 0);
/* Initiator Nonce */
pos = wpa_add_kde(pos, RSN_KEY_DATA_NONCE, kde->nonce, WPA_NONCE_LEN,
NULL, 0);
/* SMK with PNonce */
pos = wpa_add_kde(pos, RSN_KEY_DATA_SMK, smk, PMK_LEN,
key->key_nonce, WPA_NONCE_LEN);
/* Lifetime */
lifetime = htonl(43200); /* dot11RSNAConfigSMKLifetime */
pos = wpa_add_kde(pos, RSN_KEY_DATA_LIFETIME,
(u8 *) &lifetime, sizeof(lifetime), NULL, 0);
wpa_auth_logger(sm->wpa_auth, sm->addr, LOGGER_DEBUG,
"Sending SMK M4");
__wpa_send_eapol(wpa_auth, sm,
WPA_KEY_INFO_SECURE | WPA_KEY_INFO_MIC |
WPA_KEY_INFO_INSTALL | WPA_KEY_INFO_SMK_MESSAGE,
NULL, key->key_nonce, buf, pos - buf, 0, 1, 0);
os_free(buf);
}
static void wpa_send_smk_m5(struct wpa_authenticator *wpa_auth,
struct wpa_state_machine *sm,
struct wpa_eapol_key *key,
struct wpa_eapol_ie_parse *kde,
const u8 *smk, const u8 *peer)
{
u8 *buf, *pos;
size_t buf_len;
u32 lifetime;
/* SMK M5:
* EAPOL-Key(S=1, M=1, A=0, I=0, K=0, SM=1, KeyRSC=0, Nonce=INonce,
* MIC=MIC, DataKDs=(RSNIE_P, MAC_P KDE, PNonce, SMK KDE,
* Lifetime KDE))
*/
buf_len = kde->rsn_ie_len +
2 + RSN_SELECTOR_LEN + ETH_ALEN +
2 + RSN_SELECTOR_LEN + WPA_NONCE_LEN +
2 + RSN_SELECTOR_LEN + PMK_LEN + WPA_NONCE_LEN +
2 + RSN_SELECTOR_LEN + sizeof(lifetime);
pos = buf = os_malloc(buf_len);
if (buf == NULL)
return;
/* Peer RSN IE */
os_memcpy(pos, kde->rsn_ie, kde->rsn_ie_len);
pos += kde->rsn_ie_len;
/* Peer MAC Address */
pos = wpa_add_kde(pos, RSN_KEY_DATA_MAC_ADDR, peer, ETH_ALEN, NULL, 0);
/* PNonce */
pos = wpa_add_kde(pos, RSN_KEY_DATA_NONCE, key->key_nonce,
WPA_NONCE_LEN, NULL, 0);
/* SMK and INonce */
pos = wpa_add_kde(pos, RSN_KEY_DATA_SMK, smk, PMK_LEN,
kde->nonce, WPA_NONCE_LEN);
/* Lifetime */
lifetime = htonl(43200); /* dot11RSNAConfigSMKLifetime */
pos = wpa_add_kde(pos, RSN_KEY_DATA_LIFETIME,
(u8 *) &lifetime, sizeof(lifetime), NULL, 0);
wpa_auth_logger(sm->wpa_auth, sm->addr, LOGGER_DEBUG,
"Sending SMK M5");
__wpa_send_eapol(wpa_auth, sm,
WPA_KEY_INFO_SECURE | WPA_KEY_INFO_MIC |
WPA_KEY_INFO_SMK_MESSAGE,
NULL, kde->nonce, buf, pos - buf, 0, 1, 0);
os_free(buf);
}
void wpa_smk_m3(struct wpa_authenticator *wpa_auth,
struct wpa_state_machine *sm, struct wpa_eapol_key *key,
const u8 *key_data, size_t key_data_len)
{
struct wpa_eapol_ie_parse kde;
struct wpa_stsl_search search;
u8 smk[32], buf[ETH_ALEN + 8 + 2 * WPA_NONCE_LEN], *pos;
if (wpa_parse_kde_ies(key_data, key_data_len, &kde) < 0) {
wpa_printf(MSG_INFO, "RSN: Failed to parse KDEs in SMK M3");
return;
}
if (kde.rsn_ie == NULL ||
kde.mac_addr == NULL || kde.mac_addr_len < ETH_ALEN ||
kde.nonce == NULL || kde.nonce_len < WPA_NONCE_LEN) {
wpa_printf(MSG_INFO, "RSN: No RSN IE, MAC address KDE, or "
"Nonce KDE in SMK M3");
return;
}
/* Peer = sm->addr; Initiator = kde.mac_addr;
* Peer Nonce = key->key_nonce; Initiator Nonce = kde.nonce */
search.addr = kde.mac_addr;
search.sm = NULL;
if (wpa_auth_for_each_sta(wpa_auth, wpa_stsl_select_sta, &search) ==
0 || search.sm == NULL) {
wpa_printf(MSG_DEBUG, "RSN: SMK handshake with " MACSTR
" aborted - STA not associated anymore",
MAC2STR(kde.mac_addr));
wpa_smk_send_error(wpa_auth, sm, kde.mac_addr, STK_MUI_SMK,
STK_ERR_STA_NR);
return;
}
if (random_get_bytes(smk, PMK_LEN)) {
wpa_printf(MSG_DEBUG, "RSN: Failed to generate SMK");
return;
}
/* SMK = PRF-256(Random number, "SMK Derivation",
* AA || Time || INonce || PNonce)
*/
os_memcpy(buf, wpa_auth->addr, ETH_ALEN);
pos = buf + ETH_ALEN;
wpa_get_ntp_timestamp(pos);
pos += 8;
os_memcpy(pos, kde.nonce, WPA_NONCE_LEN);
pos += WPA_NONCE_LEN;
os_memcpy(pos, key->key_nonce, WPA_NONCE_LEN);
#ifdef CONFIG_IEEE80211W
sha256_prf(smk, PMK_LEN, "SMK Derivation", buf, sizeof(buf),
smk, PMK_LEN);
#else /* CONFIG_IEEE80211W */
sha1_prf(smk, PMK_LEN, "SMK Derivation", buf, sizeof(buf),
smk, PMK_LEN);
#endif /* CONFIG_IEEE80211W */
wpa_hexdump_key(MSG_DEBUG, "RSN: SMK", smk, PMK_LEN);
wpa_send_smk_m4(wpa_auth, sm, key, &kde, smk);
wpa_send_smk_m5(wpa_auth, search.sm, key, &kde, smk, sm->addr);
/* Authenticator does not need SMK anymore and it is required to forget
* it. */
os_memset(smk, 0, sizeof(*smk));
}
void wpa_smk_error(struct wpa_authenticator *wpa_auth,
struct wpa_state_machine *sm,
const u8 *key_data, size_t key_data_len)
{
struct wpa_eapol_ie_parse kde;
struct wpa_stsl_search search;
struct rsn_error_kde error;
u16 mui, error_type;
if (wpa_parse_kde_ies(key_data, key_data_len, &kde) < 0) {
wpa_printf(MSG_INFO, "RSN: Failed to parse KDEs in SMK Error");
return;
}
if (kde.mac_addr == NULL || kde.mac_addr_len < ETH_ALEN ||
kde.error == NULL || kde.error_len < sizeof(error)) {
wpa_printf(MSG_INFO, "RSN: No MAC address or Error KDE in "
"SMK Error");
return;
}
search.addr = kde.mac_addr;
search.sm = NULL;
if (wpa_auth_for_each_sta(wpa_auth, wpa_stsl_select_sta, &search) ==
0 || search.sm == NULL) {
wpa_printf(MSG_DEBUG, "RSN: Peer STA " MACSTR " not "
"associated for SMK Error message from " MACSTR,
MAC2STR(kde.mac_addr), MAC2STR(sm->addr));
return;
}
os_memcpy(&error, kde.error, sizeof(error));
mui = be_to_host16(error.mui);
error_type = be_to_host16(error.error_type);
wpa_auth_vlogger(wpa_auth, sm->addr, LOGGER_INFO,
"STA reported SMK Error: Peer " MACSTR
" MUI %d Error Type %d",
MAC2STR(kde.mac_addr), mui, error_type);
wpa_smk_send_error(wpa_auth, search.sm, sm->addr, mui, error_type);
}
#endif /* CONFIG_PEERKEY */