hostap/src/common/wpa_common.c

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/*
* WPA/RSN - Shared functions for supplicant and authenticator
* Copyright (c) 2002-2008, Jouni Malinen <j@w1.fi>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Alternatively, this software may be distributed under the terms of BSD
* license.
*
* See README and COPYING for more details.
*/
#include "includes.h"
#include "common.h"
#include "md5.h"
#include "sha1.h"
#include "sha256.h"
#include "aes_wrap.h"
#include "crypto.h"
#include "ieee802_11_defs.h"
#include "defs.h"
#include "wpa_common.h"
/**
* wpa_eapol_key_mic - Calculate EAPOL-Key MIC
* @key: EAPOL-Key Key Confirmation Key (KCK)
* @ver: Key descriptor version (WPA_KEY_INFO_TYPE_*)
* @buf: Pointer to the beginning of the EAPOL header (version field)
* @len: Length of the EAPOL frame (from EAPOL header to the end of the frame)
* @mic: Pointer to the buffer to which the EAPOL-Key MIC is written
* Returns: 0 on success, -1 on failure
*
* Calculate EAPOL-Key MIC for an EAPOL-Key packet. The EAPOL-Key MIC field has
* to be cleared (all zeroes) when calling this function.
*
* Note: 'IEEE Std 802.11i-2004 - 8.5.2 EAPOL-Key frames' has an error in the
* description of the Key MIC calculation. It includes packet data from the
* beginning of the EAPOL-Key header, not EAPOL header. This incorrect change
* happened during final editing of the standard and the correct behavior is
* defined in the last draft (IEEE 802.11i/D10).
*/
int wpa_eapol_key_mic(const u8 *key, int ver, const u8 *buf, size_t len,
u8 *mic)
{
u8 hash[SHA1_MAC_LEN];
switch (ver) {
case WPA_KEY_INFO_TYPE_HMAC_MD5_RC4:
hmac_md5(key, 16, buf, len, mic);
break;
case WPA_KEY_INFO_TYPE_HMAC_SHA1_AES:
hmac_sha1(key, 16, buf, len, hash);
os_memcpy(mic, hash, MD5_MAC_LEN);
break;
#ifdef CONFIG_IEEE80211R
case WPA_KEY_INFO_TYPE_AES_128_CMAC:
return omac1_aes_128(key, buf, len, mic);
#endif /* CONFIG_IEEE80211R */
default:
return -1;
}
return 0;
}
/**
* wpa_pmk_to_ptk - Calculate PTK from PMK, addresses, and nonces
* @pmk: Pairwise master key
* @pmk_len: Length of PMK
* @label: Label to use in derivation
* @addr1: AA or SA
* @addr2: SA or AA
* @nonce1: ANonce or SNonce
* @nonce2: SNonce or ANonce
* @ptk: Buffer for pairwise transient key
* @ptk_len: Length of PTK
* @use_sha256: Whether to use SHA256-based KDF
*
* IEEE Std 802.11i-2004 - 8.5.1.2 Pairwise key hierarchy
* PTK = PRF-X(PMK, "Pairwise key expansion",
* Min(AA, SA) || Max(AA, SA) ||
* Min(ANonce, SNonce) || Max(ANonce, SNonce))
*
* STK = PRF-X(SMK, "Peer key expansion",
* Min(MAC_I, MAC_P) || Max(MAC_I, MAC_P) ||
* Min(INonce, PNonce) || Max(INonce, PNonce))
*/
void wpa_pmk_to_ptk(const u8 *pmk, size_t pmk_len, const char *label,
const u8 *addr1, const u8 *addr2,
const u8 *nonce1, const u8 *nonce2,
u8 *ptk, size_t ptk_len, int use_sha256)
{
u8 data[2 * ETH_ALEN + 2 * WPA_NONCE_LEN];
if (os_memcmp(addr1, addr2, ETH_ALEN) < 0) {
os_memcpy(data, addr1, ETH_ALEN);
os_memcpy(data + ETH_ALEN, addr2, ETH_ALEN);
} else {
os_memcpy(data, addr2, ETH_ALEN);
os_memcpy(data + ETH_ALEN, addr1, ETH_ALEN);
}
if (os_memcmp(nonce1, nonce2, WPA_NONCE_LEN) < 0) {
os_memcpy(data + 2 * ETH_ALEN, nonce1, WPA_NONCE_LEN);
os_memcpy(data + 2 * ETH_ALEN + WPA_NONCE_LEN, nonce2,
WPA_NONCE_LEN);
} else {
os_memcpy(data + 2 * ETH_ALEN, nonce2, WPA_NONCE_LEN);
os_memcpy(data + 2 * ETH_ALEN + WPA_NONCE_LEN, nonce1,
WPA_NONCE_LEN);
}
#ifdef CONFIG_IEEE80211W
if (use_sha256)
sha256_prf(pmk, pmk_len, label, data, sizeof(data),
ptk, ptk_len);
else
#endif /* CONFIG_IEEE80211W */
sha1_prf(pmk, pmk_len, label, data, sizeof(data), ptk,
ptk_len);
wpa_printf(MSG_DEBUG, "WPA: PTK derivation - A1=" MACSTR " A2=" MACSTR,
MAC2STR(addr1), MAC2STR(addr2));
wpa_hexdump_key(MSG_DEBUG, "WPA: PMK", pmk, pmk_len);
wpa_hexdump_key(MSG_DEBUG, "WPA: PTK", ptk, ptk_len);
}
#ifdef CONFIG_IEEE80211R
int wpa_ft_mic(const u8 *kck, const u8 *sta_addr, const u8 *ap_addr,
u8 transaction_seqnum, const u8 *mdie, size_t mdie_len,
const u8 *ftie, size_t ftie_len,
const u8 *rsnie, size_t rsnie_len,
const u8 *ric, size_t ric_len, u8 *mic)
{
u8 *buf, *pos;
size_t buf_len;
buf_len = 2 * ETH_ALEN + 1 + mdie_len + ftie_len + rsnie_len + ric_len;
buf = os_malloc(buf_len);
if (buf == NULL)
return -1;
pos = buf;
os_memcpy(pos, sta_addr, ETH_ALEN);
pos += ETH_ALEN;
os_memcpy(pos, ap_addr, ETH_ALEN);
pos += ETH_ALEN;
*pos++ = transaction_seqnum;
if (rsnie) {
os_memcpy(pos, rsnie, rsnie_len);
pos += rsnie_len;
}
if (mdie) {
os_memcpy(pos, mdie, mdie_len);
pos += mdie_len;
}
if (ftie) {
struct rsn_ftie *_ftie;
os_memcpy(pos, ftie, ftie_len);
if (ftie_len < 2 + sizeof(*_ftie)) {
os_free(buf);
return -1;
}
_ftie = (struct rsn_ftie *) (pos + 2);
os_memset(_ftie->mic, 0, sizeof(_ftie->mic));
pos += ftie_len;
}
if (ric) {
os_memcpy(pos, ric, ric_len);
pos += ric_len;
}
wpa_hexdump(MSG_MSGDUMP, "FT: MIC data", buf, pos - buf);
if (omac1_aes_128(kck, buf, pos - buf, mic)) {
os_free(buf);
return -1;
}
os_free(buf);
return 0;
}
#endif /* CONFIG_IEEE80211R */
#ifndef CONFIG_NO_WPA2
static int rsn_selector_to_bitfield(const u8 *s)
{
if (RSN_SELECTOR_GET(s) == RSN_CIPHER_SUITE_NONE)
return WPA_CIPHER_NONE;
if (RSN_SELECTOR_GET(s) == RSN_CIPHER_SUITE_WEP40)
return WPA_CIPHER_WEP40;
if (RSN_SELECTOR_GET(s) == RSN_CIPHER_SUITE_TKIP)
return WPA_CIPHER_TKIP;
if (RSN_SELECTOR_GET(s) == RSN_CIPHER_SUITE_CCMP)
return WPA_CIPHER_CCMP;
if (RSN_SELECTOR_GET(s) == RSN_CIPHER_SUITE_WEP104)
return WPA_CIPHER_WEP104;
#ifdef CONFIG_IEEE80211W
if (RSN_SELECTOR_GET(s) == RSN_CIPHER_SUITE_AES_128_CMAC)
return WPA_CIPHER_AES_128_CMAC;
#endif /* CONFIG_IEEE80211W */
return 0;
}
static int rsn_key_mgmt_to_bitfield(const u8 *s)
{
if (RSN_SELECTOR_GET(s) == RSN_AUTH_KEY_MGMT_UNSPEC_802_1X)
return WPA_KEY_MGMT_IEEE8021X;
if (RSN_SELECTOR_GET(s) == RSN_AUTH_KEY_MGMT_PSK_OVER_802_1X)
return WPA_KEY_MGMT_PSK;
#ifdef CONFIG_IEEE80211R
if (RSN_SELECTOR_GET(s) == RSN_AUTH_KEY_MGMT_FT_802_1X)
return WPA_KEY_MGMT_FT_IEEE8021X;
if (RSN_SELECTOR_GET(s) == RSN_AUTH_KEY_MGMT_FT_PSK)
return WPA_KEY_MGMT_FT_PSK;
#endif /* CONFIG_IEEE80211R */
#ifdef CONFIG_IEEE80211W
if (RSN_SELECTOR_GET(s) == RSN_AUTH_KEY_MGMT_802_1X_SHA256)
return WPA_KEY_MGMT_IEEE8021X_SHA256;
if (RSN_SELECTOR_GET(s) == RSN_AUTH_KEY_MGMT_PSK_SHA256)
return WPA_KEY_MGMT_PSK_SHA256;
#endif /* CONFIG_IEEE80211W */
return 0;
}
#endif /* CONFIG_NO_WPA2 */
/**
* wpa_parse_wpa_ie_rsn - Parse RSN IE
* @rsn_ie: Buffer containing RSN IE
* @rsn_ie_len: RSN IE buffer length (including IE number and length octets)
* @data: Pointer to structure that will be filled in with parsed data
* Returns: 0 on success, <0 on failure
*/
int wpa_parse_wpa_ie_rsn(const u8 *rsn_ie, size_t rsn_ie_len,
struct wpa_ie_data *data)
{
#ifndef CONFIG_NO_WPA2
const struct rsn_ie_hdr *hdr;
const u8 *pos;
int left;
int i, count;
os_memset(data, 0, sizeof(*data));
data->proto = WPA_PROTO_RSN;
data->pairwise_cipher = WPA_CIPHER_CCMP;
data->group_cipher = WPA_CIPHER_CCMP;
data->key_mgmt = WPA_KEY_MGMT_IEEE8021X;
data->capabilities = 0;
data->pmkid = NULL;
data->num_pmkid = 0;
#ifdef CONFIG_IEEE80211W
data->mgmt_group_cipher = WPA_CIPHER_AES_128_CMAC;
#else /* CONFIG_IEEE80211W */
data->mgmt_group_cipher = 0;
#endif /* CONFIG_IEEE80211W */
if (rsn_ie_len == 0) {
/* No RSN IE - fail silently */
return -1;
}
if (rsn_ie_len < sizeof(struct rsn_ie_hdr)) {
wpa_printf(MSG_DEBUG, "%s: ie len too short %lu",
__func__, (unsigned long) rsn_ie_len);
return -1;
}
hdr = (const struct rsn_ie_hdr *) rsn_ie;
if (hdr->elem_id != WLAN_EID_RSN ||
hdr->len != rsn_ie_len - 2 ||
WPA_GET_LE16(hdr->version) != RSN_VERSION) {
wpa_printf(MSG_DEBUG, "%s: malformed ie or unknown version",
__func__);
return -2;
}
pos = (const u8 *) (hdr + 1);
left = rsn_ie_len - sizeof(*hdr);
if (left >= RSN_SELECTOR_LEN) {
data->group_cipher = rsn_selector_to_bitfield(pos);
#ifdef CONFIG_IEEE80211W
if (data->group_cipher == WPA_CIPHER_AES_128_CMAC) {
wpa_printf(MSG_DEBUG, "%s: AES-128-CMAC used as group "
"cipher", __func__);
return -1;
}
#endif /* CONFIG_IEEE80211W */
pos += RSN_SELECTOR_LEN;
left -= RSN_SELECTOR_LEN;
} else if (left > 0) {
wpa_printf(MSG_DEBUG, "%s: ie length mismatch, %u too much",
__func__, left);
return -3;
}
if (left >= 2) {
data->pairwise_cipher = 0;
count = WPA_GET_LE16(pos);
pos += 2;
left -= 2;
if (count == 0 || left < count * RSN_SELECTOR_LEN) {
wpa_printf(MSG_DEBUG, "%s: ie count botch (pairwise), "
"count %u left %u", __func__, count, left);
return -4;
}
for (i = 0; i < count; i++) {
data->pairwise_cipher |= rsn_selector_to_bitfield(pos);
pos += RSN_SELECTOR_LEN;
left -= RSN_SELECTOR_LEN;
}
#ifdef CONFIG_IEEE80211W
if (data->pairwise_cipher & WPA_CIPHER_AES_128_CMAC) {
wpa_printf(MSG_DEBUG, "%s: AES-128-CMAC used as "
"pairwise cipher", __func__);
return -1;
}
#endif /* CONFIG_IEEE80211W */
} else if (left == 1) {
wpa_printf(MSG_DEBUG, "%s: ie too short (for key mgmt)",
__func__);
return -5;
}
if (left >= 2) {
data->key_mgmt = 0;
count = WPA_GET_LE16(pos);
pos += 2;
left -= 2;
if (count == 0 || left < count * RSN_SELECTOR_LEN) {
wpa_printf(MSG_DEBUG, "%s: ie count botch (key mgmt), "
"count %u left %u", __func__, count, left);
return -6;
}
for (i = 0; i < count; i++) {
data->key_mgmt |= rsn_key_mgmt_to_bitfield(pos);
pos += RSN_SELECTOR_LEN;
left -= RSN_SELECTOR_LEN;
}
} else if (left == 1) {
wpa_printf(MSG_DEBUG, "%s: ie too short (for capabilities)",
__func__);
return -7;
}
if (left >= 2) {
data->capabilities = WPA_GET_LE16(pos);
pos += 2;
left -= 2;
}
if (left >= 2) {
data->num_pmkid = WPA_GET_LE16(pos);
pos += 2;
left -= 2;
if (left < (int) data->num_pmkid * PMKID_LEN) {
wpa_printf(MSG_DEBUG, "%s: PMKID underflow "
"(num_pmkid=%lu left=%d)",
__func__, (unsigned long) data->num_pmkid,
left);
data->num_pmkid = 0;
return -9;
} else {
data->pmkid = pos;
pos += data->num_pmkid * PMKID_LEN;
left -= data->num_pmkid * PMKID_LEN;
}
}
#ifdef CONFIG_IEEE80211W
if (left >= 4) {
data->mgmt_group_cipher = rsn_selector_to_bitfield(pos);
if (data->mgmt_group_cipher != WPA_CIPHER_AES_128_CMAC) {
wpa_printf(MSG_DEBUG, "%s: Unsupported management "
"group cipher 0x%x", __func__,
data->mgmt_group_cipher);
return -10;
}
pos += RSN_SELECTOR_LEN;
left -= RSN_SELECTOR_LEN;
}
#endif /* CONFIG_IEEE80211W */
if (left > 0) {
wpa_printf(MSG_DEBUG, "%s: ie has %u trailing bytes - ignored",
__func__, left);
}
return 0;
#else /* CONFIG_NO_WPA2 */
return -1;
#endif /* CONFIG_NO_WPA2 */
}
#ifdef CONFIG_IEEE80211R
/**
* wpa_derive_pmk_r0 - Derive PMK-R0 and PMKR0Name
*
* IEEE Std 802.11r-2008 - 8.5.1.5.3
*/
void wpa_derive_pmk_r0(const u8 *xxkey, size_t xxkey_len,
const u8 *ssid, size_t ssid_len,
const u8 *mdid, const u8 *r0kh_id, size_t r0kh_id_len,
const u8 *s0kh_id, u8 *pmk_r0, u8 *pmk_r0_name)
{
u8 buf[1 + WPA_MAX_SSID_LEN + MOBILITY_DOMAIN_ID_LEN + 1 +
FT_R0KH_ID_MAX_LEN + ETH_ALEN];
u8 *pos, r0_key_data[48], hash[32];
const u8 *addr[2];
size_t len[2];
/*
* R0-Key-Data = KDF-384(XXKey, "FT-R0",
* SSIDlength || SSID || MDID || R0KHlength ||
* R0KH-ID || S0KH-ID)
* XXKey is either the second 256 bits of MSK or PSK.
* PMK-R0 = L(R0-Key-Data, 0, 256)
* PMK-R0Name-Salt = L(R0-Key-Data, 256, 128)
*/
if (ssid_len > WPA_MAX_SSID_LEN || r0kh_id_len > FT_R0KH_ID_MAX_LEN)
return;
pos = buf;
*pos++ = ssid_len;
os_memcpy(pos, ssid, ssid_len);
pos += ssid_len;
os_memcpy(pos, mdid, MOBILITY_DOMAIN_ID_LEN);
pos += MOBILITY_DOMAIN_ID_LEN;
*pos++ = r0kh_id_len;
os_memcpy(pos, r0kh_id, r0kh_id_len);
pos += r0kh_id_len;
os_memcpy(pos, s0kh_id, ETH_ALEN);
pos += ETH_ALEN;
sha256_prf(xxkey, xxkey_len, "FT-R0", buf, pos - buf,
r0_key_data, sizeof(r0_key_data));
os_memcpy(pmk_r0, r0_key_data, PMK_LEN);
/*
* PMKR0Name = Truncate-128(SHA-256("FT-R0N" || PMK-R0Name-Salt)
*/
addr[0] = (const u8 *) "FT-R0N";
len[0] = 6;
addr[1] = r0_key_data + PMK_LEN;
len[1] = 16;
sha256_vector(2, addr, len, hash);
os_memcpy(pmk_r0_name, hash, WPA_PMK_NAME_LEN);
}
/**
* wpa_derive_pmk_r1_name - Derive PMKR1Name
*
* IEEE Std 802.11r-2008 - 8.5.1.5.4
*/
void wpa_derive_pmk_r1_name(const u8 *pmk_r0_name, const u8 *r1kh_id,
const u8 *s1kh_id, u8 *pmk_r1_name)
{
u8 hash[32];
const u8 *addr[4];
size_t len[4];
/*
* PMKR1Name = Truncate-128(SHA-256("FT-R1N" || PMKR0Name ||
* R1KH-ID || S1KH-ID))
*/
addr[0] = (const u8 *) "FT-R1N";
len[0] = 6;
addr[1] = pmk_r0_name;
len[1] = WPA_PMK_NAME_LEN;
addr[2] = r1kh_id;
len[2] = FT_R1KH_ID_LEN;
addr[3] = s1kh_id;
len[3] = ETH_ALEN;
sha256_vector(4, addr, len, hash);
os_memcpy(pmk_r1_name, hash, WPA_PMK_NAME_LEN);
}
/**
* wpa_derive_pmk_r1 - Derive PMK-R1 and PMKR1Name from PMK-R0
*
* IEEE Std 802.11r-2008 - 8.5.1.5.4
*/
void wpa_derive_pmk_r1(const u8 *pmk_r0, const u8 *pmk_r0_name,
const u8 *r1kh_id, const u8 *s1kh_id,
u8 *pmk_r1, u8 *pmk_r1_name)
{
u8 buf[FT_R1KH_ID_LEN + ETH_ALEN];
u8 *pos;
/* PMK-R1 = KDF-256(PMK-R0, "FT-R1", R1KH-ID || S1KH-ID) */
pos = buf;
os_memcpy(pos, r1kh_id, FT_R1KH_ID_LEN);
pos += FT_R1KH_ID_LEN;
os_memcpy(pos, s1kh_id, ETH_ALEN);
pos += ETH_ALEN;
sha256_prf(pmk_r0, PMK_LEN, "FT-R1", buf, pos - buf, pmk_r1, PMK_LEN);
wpa_derive_pmk_r1_name(pmk_r0_name, r1kh_id, s1kh_id, pmk_r1_name);
}
/**
* wpa_pmk_r1_to_ptk - Derive PTK and PTKName from PMK-R1
*
* IEEE Std 802.11r-2008 - 8.5.1.5.5
*/
void wpa_pmk_r1_to_ptk(const u8 *pmk_r1, const u8 *snonce, const u8 *anonce,
const u8 *sta_addr, const u8 *bssid,
const u8 *pmk_r1_name,
u8 *ptk, size_t ptk_len, u8 *ptk_name)
{
u8 buf[2 * WPA_NONCE_LEN + 2 * ETH_ALEN];
u8 *pos, hash[32];
const u8 *addr[6];
size_t len[6];
/*
* PTK = KDF-PTKLen(PMK-R1, "FT-PTK", SNonce || ANonce ||
* BSSID || STA-ADDR)
*/
pos = buf;
os_memcpy(pos, snonce, WPA_NONCE_LEN);
pos += WPA_NONCE_LEN;
os_memcpy(pos, anonce, WPA_NONCE_LEN);
pos += WPA_NONCE_LEN;
os_memcpy(pos, bssid, ETH_ALEN);
pos += ETH_ALEN;
os_memcpy(pos, sta_addr, ETH_ALEN);
pos += ETH_ALEN;
sha256_prf(pmk_r1, PMK_LEN, "FT-PTK", buf, pos - buf, ptk, ptk_len);
/*
* PTKName = Truncate-128(SHA-256(PMKR1Name || "FT-PTKN" || SNonce ||
* ANonce || BSSID || STA-ADDR))
*/
addr[0] = pmk_r1_name;
len[0] = WPA_PMK_NAME_LEN;
addr[1] = (const u8 *) "FT-PTKN";
len[1] = 7;
addr[2] = snonce;
len[2] = WPA_NONCE_LEN;
addr[3] = anonce;
len[3] = WPA_NONCE_LEN;
addr[4] = bssid;
len[4] = ETH_ALEN;
addr[5] = sta_addr;
len[5] = ETH_ALEN;
sha256_vector(6, addr, len, hash);
os_memcpy(ptk_name, hash, WPA_PMK_NAME_LEN);
}
#endif /* CONFIG_IEEE80211R */
/**
* rsn_pmkid - Calculate PMK identifier
* @pmk: Pairwise master key
* @pmk_len: Length of pmk in bytes
* @aa: Authenticator address
* @spa: Supplicant address
* @pmkid: Buffer for PMKID
* @use_sha256: Whether to use SHA256-based KDF
*
* IEEE Std 802.11i-2004 - 8.5.1.2 Pairwise key hierarchy
* PMKID = HMAC-SHA1-128(PMK, "PMK Name" || AA || SPA)
*/
void rsn_pmkid(const u8 *pmk, size_t pmk_len, const u8 *aa, const u8 *spa,
u8 *pmkid, int use_sha256)
{
char *title = "PMK Name";
const u8 *addr[3];
const size_t len[3] = { 8, ETH_ALEN, ETH_ALEN };
unsigned char hash[SHA256_MAC_LEN];
addr[0] = (u8 *) title;
addr[1] = aa;
addr[2] = spa;
#ifdef CONFIG_IEEE80211W
if (use_sha256)
hmac_sha256_vector(pmk, pmk_len, 3, addr, len, hash);
else
#endif /* CONFIG_IEEE80211W */
hmac_sha1_vector(pmk, pmk_len, 3, addr, len, hash);
os_memcpy(pmkid, hash, PMKID_LEN);
}