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hostap/src/common/wpa_common.c
Jouni Malinen 62769a88db Move cipher to enum wpa_cipher conversion into wpa_common.c 
Signed-hostap: Jouni Malinen <j@w1.fi>
2013-01-13 18:02:20 +02:00

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/*
* WPA/RSN - Shared functions for supplicant and authenticator
* Copyright (c) 2002-2013, 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 "crypto/md5.h"
#include "crypto/sha1.h"
#include "crypto/sha256.h"
#include "crypto/aes_wrap.h"
#include "crypto/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) {
#ifndef CONFIG_FIPS
case WPA_KEY_INFO_TYPE_HMAC_MD5_RC4:
return hmac_md5(key, 16, buf, len, mic);
#endif /* CONFIG_FIPS */
case WPA_KEY_INFO_TYPE_HMAC_SHA1_AES:
if (hmac_sha1(key, 16, buf, len, hash))
return -1;
os_memcpy(mic, hash, MD5_MAC_LEN);
break;
#if defined(CONFIG_IEEE80211R) || defined(CONFIG_IEEE80211W)
case WPA_KEY_INFO_TYPE_AES_128_CMAC:
return omac1_aes_128(key, buf, len, mic);
#endif /* CONFIG_IEEE80211R || CONFIG_IEEE80211W */
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(MSG_DEBUG, "WPA: Nonce1", nonce1, WPA_NONCE_LEN);
wpa_hexdump(MSG_DEBUG, "WPA: Nonce2", nonce2, WPA_NONCE_LEN);
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;
}
static int wpa_ft_parse_ftie(const u8 *ie, size_t ie_len,
struct wpa_ft_ies *parse)
{
const u8 *end, *pos;
parse->ftie = ie;
parse->ftie_len = ie_len;
pos = ie + sizeof(struct rsn_ftie);
end = ie + ie_len;
while (pos + 2 <= end && pos + 2 + pos[1] <= end) {
switch (pos[0]) {
case FTIE_SUBELEM_R1KH_ID:
if (pos[1] != FT_R1KH_ID_LEN) {
wpa_printf(MSG_DEBUG, "FT: Invalid R1KH-ID "
"length in FTIE: %d", pos[1]);
return -1;
}
parse->r1kh_id = pos + 2;
break;
case FTIE_SUBELEM_GTK:
parse->gtk = pos + 2;
parse->gtk_len = pos[1];
break;
case FTIE_SUBELEM_R0KH_ID:
if (pos[1] < 1 || pos[1] > FT_R0KH_ID_MAX_LEN) {
wpa_printf(MSG_DEBUG, "FT: Invalid R0KH-ID "
"length in FTIE: %d", pos[1]);
return -1;
}
parse->r0kh_id = pos + 2;
parse->r0kh_id_len = pos[1];
break;
#ifdef CONFIG_IEEE80211W
case FTIE_SUBELEM_IGTK:
parse->igtk = pos + 2;
parse->igtk_len = pos[1];
break;
#endif /* CONFIG_IEEE80211W */
}
pos += 2 + pos[1];
}
return 0;
}
int wpa_ft_parse_ies(const u8 *ies, size_t ies_len,
struct wpa_ft_ies *parse)
{
const u8 *end, *pos;
struct wpa_ie_data data;
int ret;
const struct rsn_ftie *ftie;
int prot_ie_count = 0;
os_memset(parse, 0, sizeof(*parse));
if (ies == NULL)
return 0;
pos = ies;
end = ies + ies_len;
while (pos + 2 <= end && pos + 2 + pos[1] <= end) {
switch (pos[0]) {
case WLAN_EID_RSN:
parse->rsn = pos + 2;
parse->rsn_len = pos[1];
ret = wpa_parse_wpa_ie_rsn(parse->rsn - 2,
parse->rsn_len + 2,
&data);
if (ret < 0) {
wpa_printf(MSG_DEBUG, "FT: Failed to parse "
"RSN IE: %d", ret);
return -1;
}
if (data.num_pmkid == 1 && data.pmkid)
parse->rsn_pmkid = data.pmkid;
break;
case WLAN_EID_MOBILITY_DOMAIN:
parse->mdie = pos + 2;
parse->mdie_len = pos[1];
break;
case WLAN_EID_FAST_BSS_TRANSITION:
if (pos[1] < sizeof(*ftie))
return -1;
ftie = (const struct rsn_ftie *) (pos + 2);
prot_ie_count = ftie->mic_control[1];
if (wpa_ft_parse_ftie(pos + 2, pos[1], parse) < 0)
return -1;
break;
case WLAN_EID_TIMEOUT_INTERVAL:
parse->tie = pos + 2;
parse->tie_len = pos[1];
break;
case WLAN_EID_RIC_DATA:
if (parse->ric == NULL)
parse->ric = pos;
break;
}
pos += 2 + pos[1];
}
if (prot_ie_count == 0)
return 0; /* no MIC */
/*
* Check that the protected IE count matches with IEs included in the
* frame.
*/
if (parse->rsn)
prot_ie_count--;
if (parse->mdie)
prot_ie_count--;
if (parse->ftie)
prot_ie_count--;
if (prot_ie_count < 0) {
wpa_printf(MSG_DEBUG, "FT: Some required IEs not included in "
"the protected IE count");
return -1;
}
if (prot_ie_count == 0 && parse->ric) {
wpa_printf(MSG_DEBUG, "FT: RIC IE(s) in the frame, but not "
"included in protected IE count");
return -1;
}
/* Determine the end of the RIC IE(s) */
pos = parse->ric;
while (pos && pos + 2 <= end && pos + 2 + pos[1] <= end &&
prot_ie_count) {
prot_ie_count--;
pos += 2 + pos[1];
}
parse->ric_len = pos - parse->ric;
if (prot_ie_count) {
wpa_printf(MSG_DEBUG, "FT: %d protected IEs missing from "
"frame", (int) prot_ie_count);
return -1;
}
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 */
if (RSN_SELECTOR_GET(s) == RSN_CIPHER_SUITE_GCMP)
return WPA_CIPHER_GCMP;
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 */
#ifdef CONFIG_SAE
if (RSN_SELECTOR_GET(s) == RSN_AUTH_KEY_MGMT_SAE)
return WPA_KEY_MGMT_SAE;
if (RSN_SELECTOR_GET(s) == RSN_AUTH_KEY_MGMT_FT_SAE)
return WPA_KEY_MGMT_FT_SAE;
#endif /* CONFIG_SAE */
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 */
}
static int wpa_selector_to_bitfield(const u8 *s)
{
if (RSN_SELECTOR_GET(s) == WPA_CIPHER_SUITE_NONE)
return WPA_CIPHER_NONE;
if (RSN_SELECTOR_GET(s) == WPA_CIPHER_SUITE_WEP40)
return WPA_CIPHER_WEP40;
if (RSN_SELECTOR_GET(s) == WPA_CIPHER_SUITE_TKIP)
return WPA_CIPHER_TKIP;
if (RSN_SELECTOR_GET(s) == WPA_CIPHER_SUITE_CCMP)
return WPA_CIPHER_CCMP;
if (RSN_SELECTOR_GET(s) == WPA_CIPHER_SUITE_WEP104)
return WPA_CIPHER_WEP104;
return 0;
}
static int wpa_key_mgmt_to_bitfield(const u8 *s)
{
if (RSN_SELECTOR_GET(s) == WPA_AUTH_KEY_MGMT_UNSPEC_802_1X)
return WPA_KEY_MGMT_IEEE8021X;
if (RSN_SELECTOR_GET(s) == WPA_AUTH_KEY_MGMT_PSK_OVER_802_1X)
return WPA_KEY_MGMT_PSK;
if (RSN_SELECTOR_GET(s) == WPA_AUTH_KEY_MGMT_NONE)
return WPA_KEY_MGMT_WPA_NONE;
return 0;
}
int wpa_parse_wpa_ie_wpa(const u8 *wpa_ie, size_t wpa_ie_len,
struct wpa_ie_data *data)
{
const struct wpa_ie_hdr *hdr;
const u8 *pos;
int left;
int i, count;
os_memset(data, 0, sizeof(*data));
data->proto = WPA_PROTO_WPA;
data->pairwise_cipher = WPA_CIPHER_TKIP;
data->group_cipher = WPA_CIPHER_TKIP;
data->key_mgmt = WPA_KEY_MGMT_IEEE8021X;
data->capabilities = 0;
data->pmkid = NULL;
data->num_pmkid = 0;
data->mgmt_group_cipher = 0;
if (wpa_ie_len == 0) {
/* No WPA IE - fail silently */
return -1;
}
if (wpa_ie_len < sizeof(struct wpa_ie_hdr)) {
wpa_printf(MSG_DEBUG, "%s: ie len too short %lu",
__func__, (unsigned long) wpa_ie_len);
return -1;
}
hdr = (const struct wpa_ie_hdr *) wpa_ie;
if (hdr->elem_id != WLAN_EID_VENDOR_SPECIFIC ||
hdr->len != wpa_ie_len - 2 ||
RSN_SELECTOR_GET(hdr->oui) != WPA_OUI_TYPE ||
WPA_GET_LE16(hdr->version) != WPA_VERSION) {
wpa_printf(MSG_DEBUG, "%s: malformed ie or unknown version",
__func__);
return -2;
}
pos = (const u8 *) (hdr + 1);
left = wpa_ie_len - sizeof(*hdr);
if (left >= WPA_SELECTOR_LEN) {
data->group_cipher = wpa_selector_to_bitfield(pos);
pos += WPA_SELECTOR_LEN;
left -= WPA_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 * WPA_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 |= wpa_selector_to_bitfield(pos);
pos += WPA_SELECTOR_LEN;
left -= WPA_SELECTOR_LEN;
}
} 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 * WPA_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 |= wpa_key_mgmt_to_bitfield(pos);
pos += WPA_SELECTOR_LEN;
left -= WPA_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 > 0) {
wpa_printf(MSG_DEBUG, "%s: ie has %u trailing bytes - ignored",
__func__, left);
}
return 0;
}
#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);
}
/**
* wpa_cipher_txt - Convert cipher suite to a text string
* @cipher: Cipher suite (WPA_CIPHER_* enum)
* Returns: Pointer to a text string of the cipher suite name
*/
const char * wpa_cipher_txt(int cipher)
{
switch (cipher) {
case WPA_CIPHER_NONE:
return "NONE";
case WPA_CIPHER_WEP40:
return "WEP-40";
case WPA_CIPHER_WEP104:
return "WEP-104";
case WPA_CIPHER_TKIP:
return "TKIP";
case WPA_CIPHER_CCMP:
return "CCMP";
case WPA_CIPHER_CCMP | WPA_CIPHER_TKIP:
return "CCMP+TKIP";
case WPA_CIPHER_GCMP:
return "GCMP";
default:
return "UNKNOWN";
}
}
/**
* wpa_key_mgmt_txt - Convert key management suite to a text string
* @key_mgmt: Key management suite (WPA_KEY_MGMT_* enum)
* @proto: WPA/WPA2 version (WPA_PROTO_*)
* Returns: Pointer to a text string of the key management suite name
*/
const char * wpa_key_mgmt_txt(int key_mgmt, int proto)
{
switch (key_mgmt) {
case WPA_KEY_MGMT_IEEE8021X:
if (proto == (WPA_PROTO_RSN | WPA_PROTO_WPA))
return "WPA2+WPA/IEEE 802.1X/EAP";
return proto == WPA_PROTO_RSN ?
"WPA2/IEEE 802.1X/EAP" : "WPA/IEEE 802.1X/EAP";
case WPA_KEY_MGMT_PSK:
if (proto == (WPA_PROTO_RSN | WPA_PROTO_WPA))
return "WPA2-PSK+WPA-PSK";
return proto == WPA_PROTO_RSN ?
"WPA2-PSK" : "WPA-PSK";
case WPA_KEY_MGMT_NONE:
return "NONE";
case WPA_KEY_MGMT_IEEE8021X_NO_WPA:
return "IEEE 802.1X (no WPA)";
#ifdef CONFIG_IEEE80211R
case WPA_KEY_MGMT_FT_IEEE8021X:
return "FT-EAP";
case WPA_KEY_MGMT_FT_PSK:
return "FT-PSK";
#endif /* CONFIG_IEEE80211R */
#ifdef CONFIG_IEEE80211W
case WPA_KEY_MGMT_IEEE8021X_SHA256:
return "WPA2-EAP-SHA256";
case WPA_KEY_MGMT_PSK_SHA256:
return "WPA2-PSK-SHA256";
#endif /* CONFIG_IEEE80211W */
default:
return "UNKNOWN";
}
}
int wpa_compare_rsn_ie(int ft_initial_assoc,
const u8 *ie1, size_t ie1len,
const u8 *ie2, size_t ie2len)
{
if (ie1 == NULL || ie2 == NULL)
return -1;
if (ie1len == ie2len && os_memcmp(ie1, ie2, ie1len) == 0)
return 0; /* identical IEs */
#ifdef CONFIG_IEEE80211R
if (ft_initial_assoc) {
struct wpa_ie_data ie1d, ie2d;
/*
* The PMKID-List in RSN IE is different between Beacon/Probe
* Response/(Re)Association Request frames and EAPOL-Key
* messages in FT initial mobility domain association. Allow
* for this, but verify that other parts of the RSN IEs are
* identical.
*/
if (wpa_parse_wpa_ie_rsn(ie1, ie1len, &ie1d) < 0 ||
wpa_parse_wpa_ie_rsn(ie2, ie2len, &ie2d) < 0)
return -1;
if (ie1d.proto == ie2d.proto &&
ie1d.pairwise_cipher == ie2d.pairwise_cipher &&
ie1d.group_cipher == ie2d.group_cipher &&
ie1d.key_mgmt == ie2d.key_mgmt &&
ie1d.capabilities == ie2d.capabilities &&
ie1d.mgmt_group_cipher == ie2d.mgmt_group_cipher)
return 0;
}
#endif /* CONFIG_IEEE80211R */
return -1;
}
#ifdef CONFIG_IEEE80211R
int wpa_insert_pmkid(u8 *ies, size_t ies_len, const u8 *pmkid)
{
u8 *start, *end, *rpos, *rend;
int added = 0;
start = ies;
end = ies + ies_len;
while (start < end) {
if (*start == WLAN_EID_RSN)
break;
start += 2 + start[1];
}
if (start >= end) {
wpa_printf(MSG_ERROR, "FT: Could not find RSN IE in "
"IEs data");
return -1;
}
wpa_hexdump(MSG_DEBUG, "FT: RSN IE before modification",
start, 2 + start[1]);
/* Find start of PMKID-Count */
rpos = start + 2;
rend = rpos + start[1];
/* Skip Version and Group Data Cipher Suite */
rpos += 2 + 4;
/* Skip Pairwise Cipher Suite Count and List */
rpos += 2 + WPA_GET_LE16(rpos) * RSN_SELECTOR_LEN;
/* Skip AKM Suite Count and List */
rpos += 2 + WPA_GET_LE16(rpos) * RSN_SELECTOR_LEN;
if (rpos == rend) {
/* Add RSN Capabilities */
os_memmove(rpos + 2, rpos, end - rpos);
*rpos++ = 0;
*rpos++ = 0;
} else {
/* Skip RSN Capabilities */
rpos += 2;
if (rpos > rend) {
wpa_printf(MSG_ERROR, "FT: Could not parse RSN IE in "
"IEs data");
return -1;
}
}
if (rpos == rend) {
/* No PMKID-Count field included; add it */
os_memmove(rpos + 2 + PMKID_LEN, rpos, end - rpos);
WPA_PUT_LE16(rpos, 1);
rpos += 2;
os_memcpy(rpos, pmkid, PMKID_LEN);
added += 2 + PMKID_LEN;
start[1] += 2 + PMKID_LEN;
} else {
/* PMKID-Count was included; use it */
if (WPA_GET_LE16(rpos) != 0) {
wpa_printf(MSG_ERROR, "FT: Unexpected PMKID "
"in RSN IE in EAPOL-Key data");
return -1;
}
WPA_PUT_LE16(rpos, 1);
rpos += 2;
os_memmove(rpos + PMKID_LEN, rpos, end - rpos);
os_memcpy(rpos, pmkid, PMKID_LEN);
added += PMKID_LEN;
start[1] += PMKID_LEN;
}
wpa_hexdump(MSG_DEBUG, "FT: RSN IE after modification "
"(PMKID inserted)", start, 2 + start[1]);
return added;
}
#endif /* CONFIG_IEEE80211R */
int wpa_cipher_key_len(int cipher)
{
switch (cipher) {
case WPA_CIPHER_CCMP:
case WPA_CIPHER_GCMP:
return 16;
case WPA_CIPHER_TKIP:
return 32;
case WPA_CIPHER_WEP104:
return 13;
case WPA_CIPHER_WEP40:
return 5;
}
return 0;
}
int wpa_cipher_rsc_len(int cipher)
{
switch (cipher) {
case WPA_CIPHER_CCMP:
case WPA_CIPHER_GCMP:
case WPA_CIPHER_TKIP:
return 6;
case WPA_CIPHER_WEP104:
case WPA_CIPHER_WEP40:
return 0;
}
return 0;
}
int wpa_cipher_to_alg(int cipher)
{
switch (cipher) {
case WPA_CIPHER_CCMP:
return WPA_ALG_CCMP;
case WPA_CIPHER_GCMP:
return WPA_ALG_GCMP;
case WPA_CIPHER_TKIP:
return WPA_ALG_TKIP;
case WPA_CIPHER_WEP104:
case WPA_CIPHER_WEP40:
return WPA_ALG_WEP;
}
return WPA_ALG_NONE;
}
enum wpa_cipher wpa_cipher_to_suite_driver(int cipher)
{
switch (cipher) {
case WPA_CIPHER_NONE:
return CIPHER_NONE;
case WPA_CIPHER_WEP40:
return CIPHER_WEP40;
case WPA_CIPHER_WEP104:
return CIPHER_WEP104;
case WPA_CIPHER_CCMP:
return CIPHER_CCMP;
case WPA_CIPHER_GCMP:
return CIPHER_GCMP;
case WPA_CIPHER_TKIP:
default:
return CIPHER_TKIP;
}
}
int wpa_cipher_valid_pairwise(int cipher)
{
return cipher == WPA_CIPHER_CCMP ||
cipher == WPA_CIPHER_GCMP ||
cipher == WPA_CIPHER_TKIP;
}
u32 wpa_cipher_to_suite(int proto, int cipher)
{
if (cipher & WPA_CIPHER_CCMP)
return (proto == WPA_PROTO_RSN ?
RSN_CIPHER_SUITE_CCMP : WPA_CIPHER_SUITE_CCMP);
if (cipher & WPA_CIPHER_GCMP)
return RSN_CIPHER_SUITE_GCMP;
if (cipher & WPA_CIPHER_TKIP)
return (proto == WPA_PROTO_RSN ?
RSN_CIPHER_SUITE_TKIP : WPA_CIPHER_SUITE_TKIP);
if (cipher & WPA_CIPHER_WEP104)
return (proto == WPA_PROTO_RSN ?
RSN_CIPHER_SUITE_WEP104 : WPA_CIPHER_SUITE_WEP104);
if (cipher & WPA_CIPHER_WEP40)
return (proto == WPA_PROTO_RSN ?
RSN_CIPHER_SUITE_WEP40 : WPA_CIPHER_SUITE_WEP40);
if (cipher & WPA_CIPHER_NONE)
return (proto == WPA_PROTO_RSN ?
RSN_CIPHER_SUITE_NONE : WPA_CIPHER_SUITE_NONE);
return 0;
}
int rsn_cipher_put_suites(u8 *pos, int ciphers)
{
int num_suites = 0;
if (ciphers & WPA_CIPHER_CCMP) {
RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_CCMP);
pos += RSN_SELECTOR_LEN;
num_suites++;
}
if (ciphers & WPA_CIPHER_GCMP) {
RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_GCMP);
pos += RSN_SELECTOR_LEN;
num_suites++;
}
if (ciphers & WPA_CIPHER_TKIP) {
RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_TKIP);
pos += RSN_SELECTOR_LEN;
num_suites++;
}
if (ciphers & WPA_CIPHER_NONE) {
RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_NONE);
pos += RSN_SELECTOR_LEN;
num_suites++;
}
return num_suites;
}
int wpa_cipher_put_suites(u8 *pos, int ciphers)
{
int num_suites = 0;
if (ciphers & WPA_CIPHER_CCMP) {
RSN_SELECTOR_PUT(pos, WPA_CIPHER_SUITE_CCMP);
pos += WPA_SELECTOR_LEN;
num_suites++;
}
if (ciphers & WPA_CIPHER_TKIP) {
RSN_SELECTOR_PUT(pos, WPA_CIPHER_SUITE_TKIP);
pos += WPA_SELECTOR_LEN;
num_suites++;
}
if (ciphers & WPA_CIPHER_NONE) {
RSN_SELECTOR_PUT(pos, WPA_CIPHER_SUITE_NONE);
pos += WPA_SELECTOR_LEN;
num_suites++;
}
return num_suites;
}
int wpa_pick_pairwise_cipher(int ciphers, int none_allowed)
{
if (ciphers & WPA_CIPHER_CCMP)
return WPA_CIPHER_CCMP;
if (ciphers & WPA_CIPHER_GCMP)
return WPA_CIPHER_GCMP;
if (ciphers & WPA_CIPHER_TKIP)
return WPA_CIPHER_TKIP;
if (none_allowed && (ciphers & WPA_CIPHER_NONE))
return WPA_CIPHER_NONE;
return -1;
}
int wpa_pick_group_cipher(int ciphers)
{
if (ciphers & WPA_CIPHER_CCMP)
return WPA_CIPHER_CCMP;
if (ciphers & WPA_CIPHER_GCMP)
return WPA_CIPHER_GCMP;
if (ciphers & WPA_CIPHER_TKIP)
return WPA_CIPHER_TKIP;
if (ciphers & WPA_CIPHER_WEP104)
return WPA_CIPHER_WEP104;
if (ciphers & WPA_CIPHER_WEP40)
return WPA_CIPHER_WEP40;
return -1;
}
int wpa_parse_cipher(const char *value)
{
int val = 0, last;
char *start, *end, *buf;
buf = os_strdup(value);
if (buf == NULL)
return -1;
start = buf;
while (*start != '\0') {
while (*start == ' ' || *start == '\t')
start++;
if (*start == '\0')
break;
end = start;
while (*end != ' ' && *end != '\t' && *end != '\0')
end++;
last = *end == '\0';
*end = '\0';
if (os_strcmp(start, "CCMP") == 0)
val |= WPA_CIPHER_CCMP;
else if (os_strcmp(start, "GCMP") == 0)
val |= WPA_CIPHER_GCMP;
else if (os_strcmp(start, "TKIP") == 0)
val |= WPA_CIPHER_TKIP;
else if (os_strcmp(start, "WEP104") == 0)
val |= WPA_CIPHER_WEP104;
else if (os_strcmp(start, "WEP40") == 0)
val |= WPA_CIPHER_WEP40;
else if (os_strcmp(start, "NONE") == 0)
val |= WPA_CIPHER_NONE;
else {
os_free(buf);
return -1;
}
if (last)
break;
start = end + 1;
}
os_free(buf);
return val;
}
int wpa_write_ciphers(char *start, char *end, int ciphers, const char *delim)
{
char *pos = start;
int ret;
if (ciphers & WPA_CIPHER_CCMP) {
ret = os_snprintf(pos, end - pos, "%sCCMP",
pos == start ? "" : delim);
if (ret < 0 || ret >= end - pos)
return -1;
pos += ret;
}
if (ciphers & WPA_CIPHER_GCMP) {
ret = os_snprintf(pos, end - pos, "%sGCMP",
pos == start ? "" : delim);
if (ret < 0 || ret >= end - pos)
return -1;
pos += ret;
}
if (ciphers & WPA_CIPHER_TKIP) {
ret = os_snprintf(pos, end - pos, "%sTKIP",
pos == start ? "" : delim);
if (ret < 0 || ret >= end - pos)
return -1;
pos += ret;
}
if (ciphers & WPA_CIPHER_WEP104) {
ret = os_snprintf(pos, end - pos, "%sWEP104",
pos == start ? "" : delim);
if (ret < 0 || ret >= end - pos)
return -1;
pos += ret;
}
if (ciphers & WPA_CIPHER_WEP40) {
ret = os_snprintf(pos, end - pos, "%sWEP40",
pos == start ? "" : delim);
if (ret < 0 || ret >= end - pos)
return -1;
pos += ret;
}
if (ciphers & WPA_CIPHER_NONE) {
ret = os_snprintf(pos, end - pos, "%sNONE",
pos == start ? "" : delim);
if (ret < 0 || ret >= end - pos)
return -1;
pos += ret;
}
return pos - start;
}
int wpa_select_ap_group_cipher(int wpa, int wpa_pairwise, int rsn_pairwise)
{
int pairwise = 0;
/* Select group cipher based on the enabled pairwise cipher suites */
if (wpa & 1)
pairwise |= wpa_pairwise;
if (wpa & 2)
pairwise |= rsn_pairwise;
if (pairwise & WPA_CIPHER_TKIP)
return WPA_CIPHER_TKIP;
if ((pairwise & (WPA_CIPHER_CCMP | WPA_CIPHER_GCMP)) == WPA_CIPHER_GCMP)
return WPA_CIPHER_GCMP;
return WPA_CIPHER_CCMP;
}
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