#include <machine/rtems-bsd-user-space.h>
/*
* Wi-Fi Protected Setup - attribute processing
* Copyright (c) 2008, 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 "crypto/sha256.h"
#include "wps_i.h"
int wps_process_authenticator(struct wps_data *wps, const u8 *authenticator,
const struct wpabuf *msg)
{
u8 hash[SHA256_MAC_LEN];
const u8 *addr[2];
size_t len[2];
if (authenticator == NULL) {
wpa_printf(MSG_DEBUG, "WPS: No Authenticator attribute "
"included");
return -1;
}
if (wps->last_msg == NULL) {
wpa_printf(MSG_DEBUG, "WPS: Last message not available for "
"validating authenticator");
return -1;
}
/* Authenticator = HMAC-SHA256_AuthKey(M_prev || M_curr*)
* (M_curr* is M_curr without the Authenticator attribute)
*/
addr[0] = wpabuf_head(wps->last_msg);
len[0] = wpabuf_len(wps->last_msg);
addr[1] = wpabuf_head(msg);
len[1] = wpabuf_len(msg) - 4 - WPS_AUTHENTICATOR_LEN;
hmac_sha256_vector(wps->authkey, WPS_AUTHKEY_LEN, 2, addr, len, hash);
if (os_memcmp_const(hash, authenticator, WPS_AUTHENTICATOR_LEN) != 0) {
wpa_printf(MSG_DEBUG, "WPS: Incorrect Authenticator");
return -1;
}
return 0;
}
int wps_process_key_wrap_auth(struct wps_data *wps, struct wpabuf *msg,
const u8 *key_wrap_auth)
{
u8 hash[SHA256_MAC_LEN];
const u8 *head;
size_t len;
if (key_wrap_auth == NULL) {
wpa_printf(MSG_DEBUG, "WPS: No KWA in decrypted attribute");
return -1;
}
head = wpabuf_head(msg);
len = wpabuf_len(msg) - 4 - WPS_KWA_LEN;
if (head + len != key_wrap_auth - 4) {
wpa_printf(MSG_DEBUG, "WPS: KWA not in the end of the "
"decrypted attribute");
return -1;
}
hmac_sha256(wps->authkey, WPS_AUTHKEY_LEN, head, len, hash);
if (os_memcmp_const(hash, key_wrap_auth, WPS_KWA_LEN) != 0) {
wpa_printf(MSG_DEBUG, "WPS: Invalid KWA");
return -1;
}
return 0;
}
static int wps_process_cred_network_idx(struct wps_credential *cred,
const u8 *idx)
{
if (idx == NULL) {
wpa_printf(MSG_DEBUG, "WPS: Credential did not include "
"Network Index");
return -1;
}
wpa_printf(MSG_DEBUG, "WPS: Network Index: %d", *idx);
return 0;
}
static int wps_process_cred_ssid(struct wps_credential *cred, const u8 *ssid,
size_t ssid_len)
{
if (ssid == NULL) {
wpa_printf(MSG_DEBUG, "WPS: Credential did not include SSID");
return -1;
}
/* Remove zero-padding since some Registrar implementations seem to use
* hardcoded 32-octet length for this attribute */
while (ssid_len > 0 && ssid[ssid_len - 1] == 0)
ssid_len--;
wpa_hexdump_ascii(MSG_DEBUG, "WPS: SSID", ssid, ssid_len);
if (ssid_len <= sizeof(cred->ssid)) {
os_memcpy(cred->ssid, ssid, ssid_len);
cred->ssid_len = ssid_len;
}
return 0;
}
static int wps_process_cred_auth_type(struct wps_credential *cred,
const u8 *auth_type)
{
if (auth_type == NULL) {
wpa_printf(MSG_DEBUG, "WPS: Credential did not include "
"Authentication Type");
return -1;
}
cred->auth_type = WPA_GET_BE16(auth_type);
wpa_printf(MSG_DEBUG, "WPS: Authentication Type: 0x%x",
cred->auth_type);
return 0;
}
static int wps_process_cred_encr_type(struct wps_credential *cred,
const u8 *encr_type)
{
if (encr_type == NULL) {
wpa_printf(MSG_DEBUG, "WPS: Credential did not include "
"Encryption Type");
return -1;
}
cred->encr_type = WPA_GET_BE16(encr_type);
wpa_printf(MSG_DEBUG, "WPS: Encryption Type: 0x%x",
cred->encr_type);
return 0;
}
static int wps_process_cred_network_key_idx(struct wps_credential *cred,
const u8 *key_idx)
{
if (key_idx == NULL)
return 0; /* optional attribute */
wpa_printf(MSG_DEBUG, "WPS: Network Key Index: %d", *key_idx);
cred->key_idx = *key_idx;
return 0;
}
static int wps_process_cred_network_key(struct wps_credential *cred,
const u8 *key, size_t key_len)
{
if (key == NULL) {
wpa_printf(MSG_DEBUG, "WPS: Credential did not include "
"Network Key");
if (cred->auth_type == WPS_AUTH_OPEN &&
cred->encr_type == WPS_ENCR_NONE) {
wpa_printf(MSG_DEBUG, "WPS: Workaround - Allow "
"missing mandatory Network Key attribute "
"for open network");
return 0;
}
return -1;
}
wpa_hexdump_key(MSG_DEBUG, "WPS: Network Key", key, key_len);
if (key_len <= sizeof(cred->key)) {
os_memcpy(cred->key, key, key_len);
cred->key_len = key_len;
}
return 0;
}
static int wps_process_cred_mac_addr(struct wps_credential *cred,
const u8 *mac_addr)
{
if (mac_addr == NULL) {
wpa_printf(MSG_DEBUG, "WPS: Credential did not include "
"MAC Address");
return -1;
}
wpa_printf(MSG_DEBUG, "WPS: MAC Address " MACSTR, MAC2STR(mac_addr));
os_memcpy(cred->mac_addr, mac_addr, ETH_ALEN);
return 0;
}
static int wps_workaround_cred_key(struct wps_credential *cred)
{
if (cred->auth_type & (WPS_AUTH_WPAPSK | WPS_AUTH_WPA2PSK) &&
cred->key_len > 8 && cred->key_len < 64 &&
cred->key[cred->key_len - 1] == 0) {
#ifdef CONFIG_WPS_STRICT
wpa_printf(MSG_INFO, "WPS: WPA/WPA2-Personal passphrase uses "
"forbidden NULL termination");
wpa_hexdump_ascii_key(MSG_INFO, "WPS: Network Key",
cred->key, cred->key_len);
return -1;
#else /* CONFIG_WPS_STRICT */
/*
* A deployed external registrar is known to encode ASCII
* passphrases incorrectly. Remove the extra NULL termination
* to fix the encoding.
*/
wpa_printf(MSG_DEBUG, "WPS: Workaround - remove NULL "
"termination from ASCII passphrase");
cred->key_len--;
#endif /* CONFIG_WPS_STRICT */
}
if (cred->auth_type & (WPS_AUTH_WPAPSK | WPS_AUTH_WPA2PSK) &&
(cred->key_len < 8 || has_ctrl_char(cred->key, cred->key_len))) {
wpa_printf(MSG_INFO, "WPS: Reject credential with invalid WPA/WPA2-Personal passphrase");
wpa_hexdump_ascii_key(MSG_INFO, "WPS: Network Key",
cred->key, cred->key_len);
return -1;
}
return 0;
}
int wps_process_cred(struct wps_parse_attr *attr,
struct wps_credential *cred)
{
wpa_printf(MSG_DEBUG, "WPS: Process Credential");
/* TODO: support multiple Network Keys */
if (wps_process_cred_network_idx(cred, attr->network_idx) ||
wps_process_cred_ssid(cred, attr->ssid, attr->ssid_len) ||
wps_process_cred_auth_type(cred, attr->auth_type) ||
wps_process_cred_encr_type(cred, attr->encr_type) ||
wps_process_cred_network_key_idx(cred, attr->network_key_idx) ||
wps_process_cred_network_key(cred, attr->network_key,
attr->network_key_len) ||
wps_process_cred_mac_addr(cred, attr->mac_addr))
return -1;
return wps_workaround_cred_key(cred);
}
int wps_process_ap_settings(struct wps_parse_attr *attr,
struct wps_credential *cred)
{
wpa_printf(MSG_DEBUG, "WPS: Processing AP Settings");
os_memset(cred, 0, sizeof(*cred));
/* TODO: optional attributes New Password and Device Password ID */
if (wps_process_cred_ssid(cred, attr->ssid, attr->ssid_len) ||
wps_process_cred_auth_type(cred, attr->auth_type) ||
wps_process_cred_encr_type(cred, attr->encr_type) ||
wps_process_cred_network_key_idx(cred, attr->network_key_idx) ||
wps_process_cred_network_key(cred, attr->network_key,
attr->network_key_len) ||
wps_process_cred_mac_addr(cred, attr->mac_addr))
return -1;
return wps_workaround_cred_key(cred);
}
