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hostap/wlantest/rx_data.c

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/*
* Received Data frame processing
* Copyright (c) 2010, 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 "utils/includes.h"
#include "utils/common.h"
#include "crypto/aes_wrap.h"
#include "crypto/crypto.h"
#include "common/defs.h"
#include "common/ieee802_11_defs.h"
#include "common/eapol_common.h"
#include "common/wpa_common.h"
#include "rsn_supp/wpa_ie.h"
#include "wlantest.h"
static const char * data_stype(u16 stype)
{
switch (stype) {
case WLAN_FC_STYPE_DATA:
return "DATA";
case WLAN_FC_STYPE_DATA_CFACK:
return "DATA-CFACK";
case WLAN_FC_STYPE_DATA_CFPOLL:
return "DATA-CFPOLL";
case WLAN_FC_STYPE_DATA_CFACKPOLL:
return "DATA-CFACKPOLL";
case WLAN_FC_STYPE_NULLFUNC:
return "NULLFUNC";
case WLAN_FC_STYPE_CFACK:
return "CFACK";
case WLAN_FC_STYPE_CFPOLL:
return "CFPOLL";
case WLAN_FC_STYPE_CFACKPOLL:
return "CFACKPOLL";
case WLAN_FC_STYPE_QOS_DATA:
return "QOSDATA";
case WLAN_FC_STYPE_QOS_DATA_CFACK:
return "QOSDATA-CFACK";
case WLAN_FC_STYPE_QOS_DATA_CFPOLL:
return "QOSDATA-CFPOLL";
case WLAN_FC_STYPE_QOS_DATA_CFACKPOLL:
return "QOSDATA-CFACKPOLL";
case WLAN_FC_STYPE_QOS_NULL:
return "QOS-NULL";
case WLAN_FC_STYPE_QOS_CFPOLL:
return "QOS-CFPOLL";
case WLAN_FC_STYPE_QOS_CFACKPOLL:
return "QOS-CFACKPOLL";
}
return "??";
}
static int check_mic(const u8 *kck, int ver, const u8 *data, size_t len)
{
u8 *buf;
int ret = -1;
struct ieee802_1x_hdr *hdr;
struct wpa_eapol_key *key;
u8 rx_mic[16];
buf = os_malloc(len);
if (buf == NULL)
return -1;
os_memcpy(buf, data, len);
hdr = (struct ieee802_1x_hdr *) buf;
key = (struct wpa_eapol_key *) (hdr + 1);
os_memcpy(rx_mic, key->key_mic, 16);
os_memset(key->key_mic, 0, 16);
if (wpa_eapol_key_mic(kck, ver, buf, len, key->key_mic) == 0 &&
os_memcmp(rx_mic, key->key_mic, 16) == 0)
ret = 0;
os_free(buf);
return ret;
}
static void rx_data_eapol_key_1_of_4(struct wlantest *wt, const u8 *dst,
const u8 *src, const u8 *data, size_t len)
{
struct wlantest_bss *bss;
struct wlantest_sta *sta;
const struct ieee802_1x_hdr *eapol;
const struct wpa_eapol_key *hdr;
wpa_printf(MSG_DEBUG, "EAPOL-Key 1/4 " MACSTR " -> " MACSTR,
MAC2STR(src), MAC2STR(dst));
bss = bss_get(wt, src);
if (bss == NULL)
return;
sta = sta_get(bss, dst);
if (sta == NULL)
return;
eapol = (const struct ieee802_1x_hdr *) data;
hdr = (const struct wpa_eapol_key *) (eapol + 1);
os_memcpy(sta->anonce, hdr->key_nonce, WPA_NONCE_LEN);
}
static int try_pmk(struct wlantest_bss *bss, struct wlantest_sta *sta,
u16 ver, const u8 *data, size_t len,
struct wlantest_pmk *pmk)
{
struct wpa_ptk ptk;
size_t ptk_len = sta->pairwise_cipher == WPA_CIPHER_TKIP ? 64 : 48;
wpa_pmk_to_ptk(pmk->pmk, sizeof(pmk->pmk),
"Pairwise key expansion",
bss->bssid, sta->addr, sta->anonce, sta->snonce,
(u8 *) &ptk, ptk_len,
wpa_key_mgmt_sha256(sta->key_mgmt));
if (check_mic(ptk.kck, ver, data, len) < 0)
return -1;
wpa_printf(MSG_INFO, "Derived PTK for STA " MACSTR " BSSID " MACSTR,
MAC2STR(sta->addr), MAC2STR(bss->bssid));
os_memcpy(&sta->ptk, &ptk, sizeof(ptk));
wpa_hexdump(MSG_DEBUG, "PTK:KCK", sta->ptk.kck, 16);
wpa_hexdump(MSG_DEBUG, "PTK:KEK", sta->ptk.kek, 16);
wpa_hexdump(MSG_DEBUG, "PTK:TK1", sta->ptk.tk1, 16);
if (ptk_len > 48)
wpa_hexdump(MSG_DEBUG, "PTK:TK2", sta->ptk.u.tk2, 16);
sta->ptk_set = 1;
os_memset(sta->rsc_tods, 0, sizeof(sta->rsc_tods));
os_memset(sta->rsc_fromds, 0, sizeof(sta->rsc_fromds));
return 0;
}
static void derive_ptk(struct wlantest *wt, struct wlantest_bss *bss,
struct wlantest_sta *sta, u16 ver,
const u8 *data, size_t len)
{
struct wlantest_pmk *pmk;
dl_list_for_each(pmk, &bss->pmk, struct wlantest_pmk, list) {
if (try_pmk(bss, sta, ver, data, len, pmk) == 0)
return;
}
dl_list_for_each(pmk, &wt->pmk, struct wlantest_pmk, list) {
if (try_pmk(bss, sta, ver, data, len, pmk) == 0)
return;
}
}
static void rx_data_eapol_key_2_of_4(struct wlantest *wt, const u8 *dst,
const u8 *src, const u8 *data, size_t len)
{
struct wlantest_bss *bss;
struct wlantest_sta *sta;
const struct ieee802_1x_hdr *eapol;
const struct wpa_eapol_key *hdr;
const u8 *key_data;
u16 key_info, key_data_len;
struct wpa_eapol_ie_parse ie;
wpa_printf(MSG_DEBUG, "EAPOL-Key 2/4 " MACSTR " -> " MACSTR,
MAC2STR(src), MAC2STR(dst));
bss = bss_get(wt, dst);
if (bss == NULL)
return;
sta = sta_get(bss, src);
if (sta == NULL)
return;
eapol = (const struct ieee802_1x_hdr *) data;
hdr = (const struct wpa_eapol_key *) (eapol + 1);
os_memcpy(sta->snonce, hdr->key_nonce, WPA_NONCE_LEN);
key_info = WPA_GET_BE16(hdr->key_info);
key_data_len = WPA_GET_BE16(hdr->key_data_length);
derive_ptk(wt, bss, sta, key_info & WPA_KEY_INFO_TYPE_MASK, data, len);
if (!sta->ptk_set) {
wpa_printf(MSG_DEBUG, "No PTK known to process EAPOL-Key 2/4");
return;
}
if (check_mic(sta->ptk.kck, key_info & WPA_KEY_INFO_TYPE_MASK,
data, len) < 0) {
wpa_printf(MSG_INFO, "Mismatch in EAPOL-Key 2/4 MIC");
return;
}
wpa_printf(MSG_DEBUG, "Valid MIC found in EAPOL-Key 2/4");
key_data = (const u8 *) (hdr + 1);
if (wpa_supplicant_parse_ies(key_data, key_data_len, &ie) < 0) {
wpa_printf(MSG_INFO, "Failed to parse EAPOL-Key Key Data");
return;
}
if (ie.wpa_ie) {
wpa_hexdump(MSG_MSGDUMP, "EAPOL-Key Key Data - WPA IE",
ie.wpa_ie, ie.wpa_ie_len);
if (os_memcmp(ie.wpa_ie, sta->rsnie, ie.wpa_ie_len) != 0) {
wpa_printf(MSG_INFO, "Mismatch in WPA IE between "
"EAPOL-Key 2/4 and (Re)Association "
"Request from " MACSTR, MAC2STR(sta->addr));
wpa_hexdump(MSG_INFO, "WPA IE in EAPOL-Key",
ie.wpa_ie, ie.wpa_ie_len);
wpa_hexdump(MSG_INFO, "WPA IE in (Re)Association "
"Request",
sta->rsnie,
sta->rsnie[0] ? 2 + sta->rsnie[1] : 0);
}
}
if (ie.rsn_ie) {
wpa_hexdump(MSG_MSGDUMP, "EAPOL-Key Key Data - RSN IE",
ie.rsn_ie, ie.rsn_ie_len);
if (os_memcmp(ie.rsn_ie, sta->rsnie, ie.rsn_ie_len) != 0) {
wpa_printf(MSG_INFO, "Mismatch in RSN IE between "
"EAPOL-Key 2/4 and (Re)Association "
"Request from " MACSTR, MAC2STR(sta->addr));
wpa_hexdump(MSG_INFO, "RSN IE in EAPOL-Key",
ie.rsn_ie, ie.rsn_ie_len);
wpa_hexdump(MSG_INFO, "RSN IE in (Re)Association "
"Request",
sta->rsnie,
sta->rsnie[0] ? 2 + sta->rsnie[1] : 0);
}
}
}
static u8 * decrypt_eapol_key_data_rc4(const u8 *kek,
const struct wpa_eapol_key *hdr,
size_t *len)
{
u8 ek[32], *buf;
u16 keydatalen = WPA_GET_BE16(hdr->key_data_length);
buf = os_malloc(keydatalen);
if (buf == NULL)
return NULL;
os_memcpy(ek, hdr->key_iv, 16);
os_memcpy(ek + 16, kek, 16);
os_memcpy(buf, hdr + 1, keydatalen);
if (rc4_skip(ek, 32, 256, buf, keydatalen)) {
wpa_printf(MSG_INFO, "RC4 failed");
os_free(buf);
return NULL;
}
*len = keydatalen;
return buf;
}
static u8 * decrypt_eapol_key_data_aes(const u8 *kek,
const struct wpa_eapol_key *hdr,
size_t *len)
{
u8 *buf;
u16 keydatalen = WPA_GET_BE16(hdr->key_data_length);
if (keydatalen % 8) {
wpa_printf(MSG_INFO, "Unsupported AES-WRAP len %d",
keydatalen);
return NULL;
}
keydatalen -= 8; /* AES-WRAP adds 8 bytes */
buf = os_malloc(keydatalen);
if (buf == NULL)
return NULL;
if (aes_unwrap(kek, keydatalen / 8, (u8 *) (hdr + 1), buf)) {
os_free(buf);
wpa_printf(MSG_INFO, "AES unwrap failed - "
"could not decrypt EAPOL-Key key data");
return NULL;
}
*len = keydatalen;
return buf;
}
static u8 * decrypt_eapol_key_data(const u8 *kek, u16 ver,
const struct wpa_eapol_key *hdr,
size_t *len)
{
switch (ver) {
case WPA_KEY_INFO_TYPE_HMAC_MD5_RC4:
return decrypt_eapol_key_data_rc4(kek, hdr, len);
case WPA_KEY_INFO_TYPE_HMAC_SHA1_AES:
case WPA_KEY_INFO_TYPE_AES_128_CMAC:
return decrypt_eapol_key_data_aes(kek, hdr, len);
default:
wpa_printf(MSG_INFO, "Unsupported EAPOL-Key Key Descriptor "
"Version %u", ver);
return NULL;
}
}
static void learn_kde_keys(struct wlantest_bss *bss, const u8 *buf, size_t len,
const u8 *rsc)
{
struct wpa_eapol_ie_parse ie;
if (wpa_supplicant_parse_ies(buf, len, &ie) < 0) {
wpa_printf(MSG_INFO, "Failed to parse EAPOL-Key Key Data");
return;
}
if (ie.wpa_ie) {
wpa_hexdump(MSG_MSGDUMP, "EAPOL-Key Key Data - WPA IE",
ie.wpa_ie, ie.wpa_ie_len);
}
if (ie.rsn_ie) {
wpa_hexdump(MSG_MSGDUMP, "EAPOL-Key Key Data - RSN IE",
ie.rsn_ie, ie.rsn_ie_len);
}
if (ie.gtk) {
wpa_hexdump(MSG_MSGDUMP, "EAPOL-Key Key Data - GTK KDE",
ie.gtk, ie.gtk_len);
if (ie.gtk_len >= 2 && ie.gtk_len <= 2 + 32) {
int id;
id = ie.gtk[0] & 0x03;
wpa_printf(MSG_DEBUG, "GTK KeyID=%u tx=%u",
id, !!(ie.gtk[0] & 0x04));
if ((ie.gtk[0] & 0xf8) || ie.gtk[1])
wpa_printf(MSG_INFO, "GTK KDE: Reserved field "
"set: %02x %02x",
ie.gtk[0], ie.gtk[1]);
wpa_hexdump(MSG_DEBUG, "GTK", ie.gtk + 2,
ie.gtk_len - 2);
bss->gtk_len[id] = ie.gtk_len - 2;
os_memcpy(bss->gtk[id], ie.gtk + 2, ie.gtk_len - 2);
bss->rsc[id][0] = rsc[5];
bss->rsc[id][1] = rsc[4];
bss->rsc[id][2] = rsc[3];
bss->rsc[id][3] = rsc[2];
bss->rsc[id][4] = rsc[1];
bss->rsc[id][5] = rsc[0];
wpa_hexdump(MSG_DEBUG, "RSC", bss->rsc[id], 6);
} else {
wpa_printf(MSG_INFO, "Invalid GTK KDE length %u",
(unsigned) ie.gtk_len);
}
}
if (ie.igtk) {
wpa_hexdump(MSG_MSGDUMP, "EAPOL-Key Key Data - IGTK KDE",
ie.igtk, ie.igtk_len);
if (ie.igtk_len == 24) {
u16 id;
id = WPA_GET_LE16(ie.igtk);
if (id > 5) {
wpa_printf(MSG_INFO, "Unexpected IGTK KeyID "
"%u", id);
} else {
wpa_printf(MSG_DEBUG, "IGTK KeyID %u", id);
wpa_hexdump(MSG_DEBUG, "IPN", ie.igtk + 2, 6);
wpa_hexdump(MSG_DEBUG, "IGTK", ie.igtk + 8,
16);
os_memcpy(bss->igtk[id], ie.igtk + 8, 16);
bss->igtk_set[id] = 1;
}
} else {
wpa_printf(MSG_INFO, "Invalid IGTK KDE length %u",
(unsigned) ie.igtk_len);
}
}
}
static void rx_data_eapol_key_3_of_4(struct wlantest *wt, const u8 *dst,
const u8 *src, const u8 *data, size_t len)
{
struct wlantest_bss *bss;
struct wlantest_sta *sta;
const struct ieee802_1x_hdr *eapol;
const struct wpa_eapol_key *hdr;
const u8 *key_data;
int recalc = 0;
u16 key_info, ver;
u8 *decrypted_buf = NULL;
const u8 *decrypted;
size_t decrypted_len = 0;
struct wpa_eapol_ie_parse ie;
wpa_printf(MSG_DEBUG, "EAPOL-Key 3/4 " MACSTR " -> " MACSTR,
MAC2STR(src), MAC2STR(dst));
bss = bss_get(wt, src);
if (bss == NULL)
return;
sta = sta_get(bss, dst);
if (sta == NULL)
return;
eapol = (const struct ieee802_1x_hdr *) data;
hdr = (const struct wpa_eapol_key *) (eapol + 1);
key_info = WPA_GET_BE16(hdr->key_info);
if (os_memcmp(sta->anonce, hdr->key_nonce, WPA_NONCE_LEN) != 0) {
wpa_printf(MSG_INFO, "EAPOL-Key ANonce mismatch between 1/4 "
"and 3/4");
recalc = 1;
}
os_memcpy(sta->anonce, hdr->key_nonce, WPA_NONCE_LEN);
if (recalc) {
derive_ptk(wt, bss, sta, key_info & WPA_KEY_INFO_TYPE_MASK,
data, len);
}
if (!sta->ptk_set) {
wpa_printf(MSG_DEBUG, "No PTK known to process EAPOL-Key 3/4");
return;
}
if (check_mic(sta->ptk.kck, key_info & WPA_KEY_INFO_TYPE_MASK,
data, len) < 0) {
wpa_printf(MSG_INFO, "Mismatch in EAPOL-Key 3/4 MIC");
return;
}
wpa_printf(MSG_DEBUG, "Valid MIC found in EAPOL-Key 3/4");
key_data = (const u8 *) (hdr + 1);
if (!(key_info & WPA_KEY_INFO_ENCR_KEY_DATA)) {
if (sta->proto & WPA_PROTO_RSN)
wpa_printf(MSG_INFO, "EAPOL-Key 3/4 without "
"EncrKeyData bit");
decrypted = key_data;
decrypted_len = WPA_GET_BE16(hdr->key_data_length);
} else {
ver = key_info & WPA_KEY_INFO_TYPE_MASK;
decrypted_buf = decrypt_eapol_key_data(sta->ptk.kek, ver, hdr,
&decrypted_len);
if (decrypted_buf == NULL) {
wpa_printf(MSG_INFO, "Failed to decrypt EAPOL-Key Key "
"Data");
return;
}
decrypted = decrypted_buf;
wpa_hexdump(MSG_DEBUG, "Decrypted EAPOL-Key Key Data",
decrypted, decrypted_len);
}
if (wt->write_pcap_dumper && decrypted != key_data) {
/* Fill in a dummy Data frame header */
u8 buf[24 + 8 + sizeof(*eapol) + sizeof(*hdr)];
struct ieee80211_hdr *h;
struct wpa_eapol_key *k;
const u8 *p;
u8 *pos;
size_t plain_len;
plain_len = decrypted_len;
p = decrypted;
while (p + 1 < decrypted + decrypted_len) {
if (p[0] == 0xdd && p[1] == 0x00) {
/* Remove padding */
plain_len = p - decrypted;
break;
}
p += 2 + p[1];
}
os_memset(buf, 0, sizeof(buf));
h = (struct ieee80211_hdr *) buf;
h->frame_control = host_to_le16(0x0208);
os_memcpy(h->addr1, dst, ETH_ALEN);
os_memcpy(h->addr2, src, ETH_ALEN);
os_memcpy(h->addr3, src, ETH_ALEN);
pos = (u8 *) (h + 1);
os_memcpy(pos, "\xaa\xaa\x03\x00\x00\x00\x88\x8e", 8);
pos += 8;
os_memcpy(pos, eapol, sizeof(*eapol));
pos += sizeof(*eapol);
os_memcpy(pos, hdr, sizeof(*hdr));
k = (struct wpa_eapol_key *) pos;
WPA_PUT_BE16(k->key_info,
key_info & ~WPA_KEY_INFO_ENCR_KEY_DATA);
WPA_PUT_BE16(k->key_data_length, plain_len);
write_pcap_decrypted(wt, buf, sizeof(buf),
decrypted, plain_len);
}
if (wpa_supplicant_parse_ies(decrypted, decrypted_len, &ie) < 0) {
wpa_printf(MSG_INFO, "Failed to parse EAPOL-Key Key Data");
os_free(decrypted_buf);
return;
}
if ((ie.wpa_ie &&
os_memcmp(ie.wpa_ie, bss->wpaie, ie.wpa_ie_len) != 0) ||
(ie.wpa_ie == NULL && bss->wpaie[0])) {
wpa_printf(MSG_INFO, "Mismatch in WPA IE between "
"EAPOL-Key 3/4 and Beacon/Probe Response "
"from " MACSTR, MAC2STR(bss->bssid));
wpa_hexdump(MSG_INFO, "WPA IE in EAPOL-Key",
ie.wpa_ie, ie.wpa_ie_len);
wpa_hexdump(MSG_INFO, "WPA IE in Beacon/Probe "
"Response",
bss->wpaie,
bss->wpaie[0] ? 2 + bss->wpaie[1] : 0);
}
if ((ie.rsn_ie &&
os_memcmp(ie.rsn_ie, bss->rsnie, ie.rsn_ie_len) != 0) ||
(ie.rsn_ie == NULL && bss->rsnie[0])) {
wpa_printf(MSG_INFO, "Mismatch in RSN IE between "
"EAPOL-Key 3/4 and Beacon/Probe Response "
"from " MACSTR, MAC2STR(bss->bssid));
wpa_hexdump(MSG_INFO, "RSN IE in EAPOL-Key",
ie.rsn_ie, ie.rsn_ie_len);
wpa_hexdump(MSG_INFO, "RSN IE in (Re)Association "
"Request",
bss->rsnie,
bss->rsnie[0] ? 2 + bss->rsnie[1] : 0);
}
learn_kde_keys(bss, decrypted, decrypted_len, hdr->key_rsc);
os_free(decrypted_buf);
}
static void rx_data_eapol_key_4_of_4(struct wlantest *wt, const u8 *dst,
const u8 *src, const u8 *data, size_t len)
{
struct wlantest_bss *bss;
struct wlantest_sta *sta;
const struct ieee802_1x_hdr *eapol;
const struct wpa_eapol_key *hdr;
u16 key_info;
wpa_printf(MSG_DEBUG, "EAPOL-Key 4/4 " MACSTR " -> " MACSTR,
MAC2STR(src), MAC2STR(dst));
bss = bss_get(wt, dst);
if (bss == NULL)
return;
sta = sta_get(bss, src);
if (sta == NULL)
return;
eapol = (const struct ieee802_1x_hdr *) data;
hdr = (const struct wpa_eapol_key *) (eapol + 1);
key_info = WPA_GET_BE16(hdr->key_info);
if (!sta->ptk_set) {
wpa_printf(MSG_DEBUG, "No PTK known to process EAPOL-Key 4/4");
return;
}
if (sta->ptk_set &&
check_mic(sta->ptk.kck, key_info & WPA_KEY_INFO_TYPE_MASK,
data, len) < 0) {
wpa_printf(MSG_INFO, "Mismatch in EAPOL-Key 4/4 MIC");
return;
}
wpa_printf(MSG_DEBUG, "Valid MIC found in EAPOL-Key 4/4");
}
static void rx_data_eapol_key_1_of_2(struct wlantest *wt, const u8 *dst,
const u8 *src, const u8 *data, size_t len)
{
struct wlantest_bss *bss;
struct wlantest_sta *sta;
const struct ieee802_1x_hdr *eapol;
const struct wpa_eapol_key *hdr;
const u8 *key_data;
u16 key_info, ver;
u8 *decrypted;
size_t decrypted_len = 0;
wpa_printf(MSG_DEBUG, "EAPOL-Key 1/2 " MACSTR " -> " MACSTR,
MAC2STR(src), MAC2STR(dst));
bss = bss_get(wt, src);
if (bss == NULL)
return;
sta = sta_get(bss, dst);
if (sta == NULL)
return;
eapol = (const struct ieee802_1x_hdr *) data;
hdr = (const struct wpa_eapol_key *) (eapol + 1);
key_info = WPA_GET_BE16(hdr->key_info);
if (!sta->ptk_set) {
wpa_printf(MSG_DEBUG, "No PTK known to process EAPOL-Key 1/2");
return;
}
if (sta->ptk_set &&
check_mic(sta->ptk.kck, key_info & WPA_KEY_INFO_TYPE_MASK,
data, len) < 0) {
wpa_printf(MSG_INFO, "Mismatch in EAPOL-Key 1/2 MIC");
return;
}
wpa_printf(MSG_DEBUG, "Valid MIC found in EAPOL-Key 1/2");
key_data = (const u8 *) (hdr + 1);
if (sta->proto & WPA_PROTO_RSN &&
!(key_info & WPA_KEY_INFO_ENCR_KEY_DATA)) {
wpa_printf(MSG_INFO, "EAPOL-Key 1/2 without EncrKeyData bit");
return;
}
ver = key_info & WPA_KEY_INFO_TYPE_MASK;
decrypted = decrypt_eapol_key_data(sta->ptk.kek, ver, hdr,
&decrypted_len);
if (decrypted == NULL) {
wpa_printf(MSG_INFO, "Failed to decrypt EAPOL-Key Key Data");
return;
}
wpa_hexdump(MSG_DEBUG, "Decrypted EAPOL-Key Key Data",
decrypted, decrypted_len);
if (wt->write_pcap_dumper) {
/* Fill in a dummy Data frame header */
u8 buf[24 + 8 + sizeof(*eapol) + sizeof(*hdr)];
struct ieee80211_hdr *h;
struct wpa_eapol_key *k;
u8 *pos;
size_t plain_len;
plain_len = decrypted_len;
pos = decrypted;
while (pos + 1 < decrypted + decrypted_len) {
if (pos[0] == 0xdd && pos[1] == 0x00) {
/* Remove padding */
plain_len = pos - decrypted;
break;
}
pos += 2 + pos[1];
}
os_memset(buf, 0, sizeof(buf));
h = (struct ieee80211_hdr *) buf;
h->frame_control = host_to_le16(0x0208);
os_memcpy(h->addr1, dst, ETH_ALEN);
os_memcpy(h->addr2, src, ETH_ALEN);
os_memcpy(h->addr3, src, ETH_ALEN);
pos = (u8 *) (h + 1);
os_memcpy(pos, "\xaa\xaa\x03\x00\x00\x00\x88\x8e", 8);
pos += 8;
os_memcpy(pos, eapol, sizeof(*eapol));
pos += sizeof(*eapol);
os_memcpy(pos, hdr, sizeof(*hdr));
k = (struct wpa_eapol_key *) pos;
WPA_PUT_BE16(k->key_info,
key_info & ~WPA_KEY_INFO_ENCR_KEY_DATA);
WPA_PUT_BE16(k->key_data_length, plain_len);
write_pcap_decrypted(wt, buf, sizeof(buf),
decrypted, plain_len);
}
if (sta->proto & WPA_PROTO_RSN)
learn_kde_keys(bss, decrypted, decrypted_len, hdr->key_rsc);
else {
int len = bss->group_cipher == WPA_CIPHER_TKIP ? 32 : 16;
if (decrypted_len == len) {
const u8 *rsc = hdr->key_rsc;
int id;
id = (key_info & WPA_KEY_INFO_KEY_INDEX_MASK) >>
WPA_KEY_INFO_KEY_INDEX_SHIFT;
wpa_printf(MSG_DEBUG, "GTK key index %d", id);
wpa_hexdump(MSG_DEBUG, "GTK", decrypted,
decrypted_len);
bss->gtk_len[id] = decrypted_len;
os_memcpy(bss->gtk[id], decrypted, decrypted_len);
bss->rsc[id][0] = rsc[5];
bss->rsc[id][1] = rsc[4];
bss->rsc[id][2] = rsc[3];
bss->rsc[id][3] = rsc[2];
bss->rsc[id][4] = rsc[1];
bss->rsc[id][5] = rsc[0];
wpa_hexdump(MSG_DEBUG, "RSC", bss->rsc[id], 6);
} else {
wpa_printf(MSG_INFO, "Unexpected WPA Key Data length "
"in Group Key msg 1/2 from " MACSTR,
MAC2STR(src));
}
}
os_free(decrypted);
}
static void rx_data_eapol_key_2_of_2(struct wlantest *wt, const u8 *dst,
const u8 *src, const u8 *data, size_t len)
{
struct wlantest_bss *bss;
struct wlantest_sta *sta;
const struct ieee802_1x_hdr *eapol;
const struct wpa_eapol_key *hdr;
u16 key_info;
wpa_printf(MSG_DEBUG, "EAPOL-Key 2/2 " MACSTR " -> " MACSTR,
MAC2STR(src), MAC2STR(dst));
bss = bss_get(wt, dst);
if (bss == NULL)
return;
sta = sta_get(bss, src);
if (sta == NULL)
return;
eapol = (const struct ieee802_1x_hdr *) data;
hdr = (const struct wpa_eapol_key *) (eapol + 1);
key_info = WPA_GET_BE16(hdr->key_info);
if (!sta->ptk_set) {
wpa_printf(MSG_DEBUG, "No PTK known to process EAPOL-Key 2/2");
return;
}
if (sta->ptk_set &&
check_mic(sta->ptk.kck, key_info & WPA_KEY_INFO_TYPE_MASK,
data, len) < 0) {
wpa_printf(MSG_INFO, "Mismatch in EAPOL-Key 2/2 MIC");
return;
}
wpa_printf(MSG_DEBUG, "Valid MIC found in EAPOL-Key 2/2");
}
static void rx_data_eapol_key(struct wlantest *wt, const u8 *dst,
const u8 *src, const u8 *data, size_t len,
int prot)
{
const struct ieee802_1x_hdr *eapol;
const struct wpa_eapol_key *hdr;
const u8 *key_data;
u16 key_info, key_length, ver, key_data_length;
eapol = (const struct ieee802_1x_hdr *) data;
hdr = (const struct wpa_eapol_key *) (eapol + 1);
wpa_hexdump(MSG_MSGDUMP, "EAPOL-Key",
(const u8 *) hdr, len - sizeof(*eapol));
if (len < sizeof(*hdr)) {
wpa_printf(MSG_INFO, "Too short EAPOL-Key frame from " MACSTR,
MAC2STR(src));
return;
}
if (hdr->type == EAPOL_KEY_TYPE_RC4) {
/* TODO: EAPOL-Key RC4 for WEP */
return;
}
if (hdr->type != EAPOL_KEY_TYPE_RSN &&
hdr->type != EAPOL_KEY_TYPE_WPA) {
wpa_printf(MSG_DEBUG, "Unsupported EAPOL-Key type %u",
hdr->type);
return;
}
key_info = WPA_GET_BE16(hdr->key_info);
key_length = WPA_GET_BE16(hdr->key_length);
key_data_length = WPA_GET_BE16(hdr->key_data_length);
key_data = (const u8 *) (hdr + 1);
if (key_data + key_data_length > data + len) {
wpa_printf(MSG_INFO, "Truncated EAPOL-Key from " MACSTR,
MAC2STR(src));
return;
}
if (key_data + key_data_length < data + len) {
wpa_hexdump(MSG_DEBUG, "Extra data after EAPOL-Key Key Data "
"field", key_data + key_data_length,
data + len - key_data - key_data_length);
}
ver = key_info & WPA_KEY_INFO_TYPE_MASK;
wpa_printf(MSG_DEBUG, "EAPOL-Key ver=%u %c idx=%u%s%s%s%s%s%s%s%s "
"datalen=%u",
ver, key_info & WPA_KEY_INFO_KEY_TYPE ? 'P' : 'G',
(key_info & WPA_KEY_INFO_KEY_INDEX_MASK) >>
WPA_KEY_INFO_KEY_INDEX_SHIFT,
(key_info & WPA_KEY_INFO_INSTALL) ? " Install" : "",
(key_info & WPA_KEY_INFO_ACK) ? " ACK" : "",
(key_info & WPA_KEY_INFO_MIC) ? " MIC" : "",
(key_info & WPA_KEY_INFO_SECURE) ? " Secure" : "",
(key_info & WPA_KEY_INFO_ERROR) ? " Error" : "",
(key_info & WPA_KEY_INFO_REQUEST) ? " Request" : "",
(key_info & WPA_KEY_INFO_ENCR_KEY_DATA) ? " Encr" : "",
(key_info & WPA_KEY_INFO_SMK_MESSAGE) ? " SMK" : "",
key_data_length);
if (ver != WPA_KEY_INFO_TYPE_HMAC_MD5_RC4 &&
ver != WPA_KEY_INFO_TYPE_HMAC_SHA1_AES &&
ver != WPA_KEY_INFO_TYPE_AES_128_CMAC) {
wpa_printf(MSG_DEBUG, "Unsupported EAPOL-Key Key Descriptor "
"Version %u", ver);
return;
}
wpa_hexdump(MSG_MSGDUMP, "EAPOL-Key Replay Counter",
hdr->replay_counter, WPA_REPLAY_COUNTER_LEN);
wpa_hexdump(MSG_MSGDUMP, "EAPOL-Key Key Nonce",
hdr->key_nonce, WPA_NONCE_LEN);
wpa_hexdump(MSG_MSGDUMP, "EAPOL-Key Key IV",
hdr->key_iv, 16);
wpa_hexdump(MSG_MSGDUMP, "EAPOL-Key RSC",
hdr->key_rsc, WPA_KEY_RSC_LEN);
wpa_hexdump(MSG_MSGDUMP, "EAPOL-Key Key MIC",
hdr->key_mic, 16);
wpa_hexdump(MSG_MSGDUMP, "EAPOL-Key Key Data",
key_data, key_data_length);
if (key_info & (WPA_KEY_INFO_ERROR | WPA_KEY_INFO_REQUEST))
return;
if (key_info & WPA_KEY_INFO_SMK_MESSAGE)
return;
if (key_info & WPA_KEY_INFO_KEY_TYPE) {
/* 4-Way Handshake */
switch (key_info & (WPA_KEY_INFO_SECURE |
WPA_KEY_INFO_MIC |
WPA_KEY_INFO_ACK |
WPA_KEY_INFO_INSTALL)) {
case WPA_KEY_INFO_ACK:
rx_data_eapol_key_1_of_4(wt, dst, src, data, len);
break;
case WPA_KEY_INFO_MIC:
rx_data_eapol_key_2_of_4(wt, dst, src, data, len);
break;
case WPA_KEY_INFO_MIC | WPA_KEY_INFO_ACK |
WPA_KEY_INFO_INSTALL:
/* WPA does not include Secure bit in 3/4 */
rx_data_eapol_key_3_of_4(wt, dst, src, data, len);
break;
case WPA_KEY_INFO_SECURE | WPA_KEY_INFO_MIC |
WPA_KEY_INFO_ACK | WPA_KEY_INFO_INSTALL:
rx_data_eapol_key_3_of_4(wt, dst, src, data, len);
break;
case WPA_KEY_INFO_SECURE | WPA_KEY_INFO_MIC:
rx_data_eapol_key_4_of_4(wt, dst, src, data, len);
break;
default:
wpa_printf(MSG_DEBUG, "Unsupported EAPOL-Key frame");
break;
}
} else {
/* Group Key Handshake */
switch (key_info & (WPA_KEY_INFO_SECURE |
WPA_KEY_INFO_MIC |
WPA_KEY_INFO_ACK)) {
case WPA_KEY_INFO_SECURE | WPA_KEY_INFO_MIC |
WPA_KEY_INFO_ACK:
rx_data_eapol_key_1_of_2(wt, dst, src, data, len);
break;
case WPA_KEY_INFO_SECURE | WPA_KEY_INFO_MIC:
rx_data_eapol_key_2_of_2(wt, dst, src, data, len);
break;
default:
wpa_printf(MSG_DEBUG, "Unsupported EAPOL-Key frame");
break;
}
}
}
static void rx_data_eapol(struct wlantest *wt, const u8 *dst, const u8 *src,
const u8 *data, size_t len, int prot)
{
const struct ieee802_1x_hdr *hdr;
u16 length;
const u8 *p;
wpa_hexdump(MSG_EXCESSIVE, "EAPOL", data, len);
if (len < sizeof(*hdr)) {
wpa_printf(MSG_INFO, "Too short EAPOL frame from " MACSTR,
MAC2STR(src));
return;
}
hdr = (const struct ieee802_1x_hdr *) data;
length = be_to_host16(hdr->length);
wpa_printf(MSG_DEBUG, "RX EAPOL: " MACSTR " -> " MACSTR "%s ver=%u "
"type=%u len=%u",
MAC2STR(src), MAC2STR(dst), prot ? " Prot" : "",
hdr->version, hdr->type, length);
if (sizeof(*hdr) + length > len) {
wpa_printf(MSG_INFO, "Truncated EAPOL frame from " MACSTR,
MAC2STR(src));
return;
}
if (sizeof(*hdr) + length < len) {
wpa_printf(MSG_INFO, "EAPOL frame with %d extra bytes",
(int) (len - sizeof(*hdr) - length));
}
p = (const u8 *) (hdr + 1);
switch (hdr->type) {
case IEEE802_1X_TYPE_EAP_PACKET:
wpa_hexdump(MSG_MSGDUMP, "EAPOL - EAP packet", p, length);
break;
case IEEE802_1X_TYPE_EAPOL_START:
wpa_hexdump(MSG_MSGDUMP, "EAPOL-Start", p, length);
break;
case IEEE802_1X_TYPE_EAPOL_LOGOFF:
wpa_hexdump(MSG_MSGDUMP, "EAPOL-Logoff", p, length);
break;
case IEEE802_1X_TYPE_EAPOL_KEY:
rx_data_eapol_key(wt, dst, src, data, sizeof(*hdr) + length,
prot);
break;
case IEEE802_1X_TYPE_EAPOL_ENCAPSULATED_ASF_ALERT:
wpa_hexdump(MSG_MSGDUMP, "EAPOL - Encapsulated ASF alert",
p, length);
break;
default:
wpa_hexdump(MSG_MSGDUMP, "Unknown EAPOL payload", p, length);
break;
}
}
static void rx_data_eth(struct wlantest *wt, const u8 *dst, const u8 *src,
u16 ethertype, const u8 *data, size_t len, int prot)
{
if (ethertype == ETH_P_PAE)
rx_data_eapol(wt, dst, src, data, len, prot);
}
static void rx_data_process(struct wlantest *wt, const u8 *dst, const u8 *src,
const u8 *data, size_t len, int prot)
{
if (len == 0)
return;
if (len >= 8 && os_memcmp(data, "\xaa\xaa\x03\x00\x00\x00", 6) == 0) {
rx_data_eth(wt, dst, src, WPA_GET_BE16(data + 6),
data + 8, len - 8, prot);
return;
}
wpa_hexdump(MSG_DEBUG, "Unrecognized LLC", data, len > 8 ? 8 : len);
}
static void rx_data_bss_prot_group(struct wlantest *wt,
const struct ieee80211_hdr *hdr,
const u8 *qos, const u8 *dst, const u8 *src,
const u8 *data, size_t len)
{
struct wlantest_bss *bss;
int keyid;
u8 *decrypted;
size_t dlen;
u8 pn[6];
bss = bss_get(wt, hdr->addr2);
if (bss == NULL)
return;
if (len < 4) {
wpa_printf(MSG_INFO, "Too short group addressed data frame");
return;
}
if (bss->group_cipher & (WPA_CIPHER_TKIP | WPA_CIPHER_CCMP) &&
!(data[3] & 0x20)) {
wpa_printf(MSG_INFO, "Expected TKIP/CCMP frame from "
MACSTR " did not have ExtIV bit set to 1",
MAC2STR(bss->bssid));
return;
}
if (bss->group_cipher == WPA_CIPHER_TKIP) {
if (data[3] & 0x1f) {
wpa_printf(MSG_INFO, "TKIP frame from " MACSTR " used "
"non-zero reserved bit",
MAC2STR(bss->bssid));
}
if (data[1] != ((data[0] | 0x20) & 0x7f)) {
wpa_printf(MSG_INFO, "TKIP frame from " MACSTR " used "
"incorrect WEPSeed[1] (was 0x%x, expected "
"0x%x)",
MAC2STR(bss->bssid), data[1],
(data[0] | 0x20) & 0x7f);
}
} else if (bss->group_cipher == WPA_CIPHER_CCMP) {
if (data[2] != 0 || (data[3] & 0x1f) != 0) {
wpa_printf(MSG_INFO, "CCMP frame from " MACSTR " used "
"non-zero reserved bit",
MAC2STR(bss->bssid));
}
}
keyid = data[3] >> 6;
if (bss->gtk_len[keyid] == 0) {
wpa_printf(MSG_MSGDUMP, "No GTK known to decrypt the frame "
"(A2=" MACSTR " KeyID=%d)",
MAC2STR(hdr->addr2), keyid);
return;
}
if (bss->group_cipher == WPA_CIPHER_TKIP)
tkip_get_pn(pn, data);
else
ccmp_get_pn(pn, data);
if (os_memcmp(pn, bss->rsc[keyid], 6) <= 0) {
wpa_printf(MSG_INFO, "CCMP/TKIP replay detected: SA=" MACSTR,
MAC2STR(hdr->addr2));
wpa_hexdump(MSG_INFO, "RX PN", pn, 6);
wpa_hexdump(MSG_INFO, "RSC", bss->rsc[keyid], 6);
}
if (bss->group_cipher == WPA_CIPHER_TKIP)
decrypted = tkip_decrypt(bss->gtk[keyid], hdr, data, len,
&dlen);
else
decrypted = ccmp_decrypt(bss->gtk[keyid], hdr, data, len,
&dlen);
if (decrypted) {
rx_data_process(wt, dst, src, decrypted, dlen, 1);
os_memcpy(bss->rsc[keyid], pn, 6);
write_pcap_decrypted(wt, (const u8 *) hdr, 24 + (qos ? 2 : 0),
decrypted, dlen);
}
os_free(decrypted);
}
static void rx_data_bss_prot(struct wlantest *wt,
const struct ieee80211_hdr *hdr, const u8 *qos,
const u8 *dst, const u8 *src, const u8 *data,
size_t len)
{
struct wlantest_bss *bss;
struct wlantest_sta *sta;
int keyid;
u16 fc = le_to_host16(hdr->frame_control);
u8 *decrypted;
size_t dlen;
int tid;
u8 pn[6], *rsc;
if (hdr->addr1[0] & 0x01) {
rx_data_bss_prot_group(wt, hdr, qos, dst, src, data, len);
return;
}
if (fc & WLAN_FC_TODS) {
bss = bss_get(wt, hdr->addr1);
if (bss == NULL)
return;
sta = sta_get(bss, hdr->addr2);
} else {
bss = bss_get(wt, hdr->addr2);
if (bss == NULL)
return;
sta = sta_get(bss, hdr->addr1);
}
if (sta == NULL || !sta->ptk_set) {
wpa_printf(MSG_MSGDUMP, "No PTK known to decrypt the frame");
return;
}
if (len < 4) {
wpa_printf(MSG_INFO, "Too short encrypted data frame");
return;
}
if (sta->pairwise_cipher & (WPA_CIPHER_TKIP | WPA_CIPHER_CCMP) &&
!(data[3] & 0x20)) {
wpa_printf(MSG_INFO, "Expected TKIP/CCMP frame from "
MACSTR " did not have ExtIV bit set to 1",
MAC2STR(src));
return;
}
if (sta->pairwise_cipher == WPA_CIPHER_TKIP) {
if (data[3] & 0x1f) {
wpa_printf(MSG_INFO, "TKIP frame from " MACSTR " used "
"non-zero reserved bit",
MAC2STR(hdr->addr2));
}
if (data[1] != ((data[0] | 0x20) & 0x7f)) {
wpa_printf(MSG_INFO, "TKIP frame from " MACSTR " used "
"incorrect WEPSeed[1] (was 0x%x, expected "
"0x%x)",
MAC2STR(hdr->addr2), data[1],
(data[0] | 0x20) & 0x7f);
}
} else if (sta->pairwise_cipher == WPA_CIPHER_CCMP) {
if (data[2] != 0 || (data[3] & 0x1f) != 0) {
wpa_printf(MSG_INFO, "CCMP frame from " MACSTR " used "
"non-zero reserved bit",
MAC2STR(hdr->addr2));
}
}
keyid = data[3] >> 6;
if (keyid != 0) {
wpa_printf(MSG_INFO, "Unexpected non-zero KeyID %d in "
"individually addressed Data frame from " MACSTR,
keyid, MAC2STR(hdr->addr2));
}
if (qos)
tid = qos[0] & 0x0f;
else
tid = 0;
if (fc & WLAN_FC_TODS)
rsc = sta->rsc_tods[tid];
else
rsc = sta->rsc_fromds[tid];
if (sta->pairwise_cipher == WPA_CIPHER_TKIP)
tkip_get_pn(pn, data);
else
ccmp_get_pn(pn, data);
if (os_memcmp(pn, rsc, 6) <= 0) {
wpa_printf(MSG_INFO, "CCMP/TKIP replay detected: SA=" MACSTR,
MAC2STR(hdr->addr2));
wpa_hexdump(MSG_INFO, "RX PN", pn, 6);
wpa_hexdump(MSG_INFO, "RSC", rsc, 6);
}
if (sta->pairwise_cipher == WPA_CIPHER_TKIP)
decrypted = tkip_decrypt(sta->ptk.tk1, hdr, data, len, &dlen);
else
decrypted = ccmp_decrypt(sta->ptk.tk1, hdr, data, len, &dlen);
if (decrypted) {
rx_data_process(wt, dst, src, decrypted, dlen, 1);
os_memcpy(rsc, pn, 6);
write_pcap_decrypted(wt, (const u8 *) hdr, 24 + (qos ? 2 : 0),
decrypted, dlen);
}
os_free(decrypted);
}
static void rx_data_bss(struct wlantest *wt, const struct ieee80211_hdr *hdr,
const u8 *qos, const u8 *dst, const u8 *src,
const u8 *data, size_t len)
{
u16 fc = le_to_host16(hdr->frame_control);
int prot = !!(fc & WLAN_FC_ISWEP);
if (qos) {
u8 ack = (qos[0] & 0x60) >> 5;
wpa_printf(MSG_MSGDUMP, "BSS DATA: " MACSTR " -> " MACSTR
" len=%u%s tid=%u%s%s",
MAC2STR(src), MAC2STR(dst), (unsigned int) len,
prot ? " Prot" : "", qos[0] & 0x0f,
(qos[0] & 0x10) ? " EOSP" : "",
ack == 0 ? "" :
(ack == 1 ? " NoAck" :
(ack == 2 ? " NoExpAck" : " BA")));
} else {
wpa_printf(MSG_MSGDUMP, "BSS DATA: " MACSTR " -> " MACSTR
" len=%u%s",
MAC2STR(src), MAC2STR(dst), (unsigned int) len,
prot ? " Prot" : "");
}
if (prot)
rx_data_bss_prot(wt, hdr, qos, dst, src, data, len);
else
rx_data_process(wt, dst, src, data, len, 0);
}
void rx_data(struct wlantest *wt, const u8 *data, size_t len)
{
const struct ieee80211_hdr *hdr;
u16 fc, stype;
size_t hdrlen;
const u8 *qos = NULL;
if (len < 24)
return;
hdr = (const struct ieee80211_hdr *) data;
fc = le_to_host16(hdr->frame_control);
stype = WLAN_FC_GET_STYPE(fc);
hdrlen = 24;
if ((fc & (WLAN_FC_TODS | WLAN_FC_FROMDS)) ==
(WLAN_FC_TODS | WLAN_FC_FROMDS))
hdrlen += ETH_ALEN;
if (stype & 0x08) {
qos = data + hdrlen;
hdrlen += 2;
}
if (len < hdrlen)
return;
wt->rx_data++;
switch (fc & (WLAN_FC_TODS | WLAN_FC_FROMDS)) {
case 0:
wpa_printf(MSG_EXCESSIVE, "DATA %s%s%s IBSS DA=" MACSTR " SA="
MACSTR " BSSID=" MACSTR,
data_stype(WLAN_FC_GET_STYPE(fc)),
fc & WLAN_FC_PWRMGT ? " PwrMgt" : "",
fc & WLAN_FC_ISWEP ? " Prot" : "",
MAC2STR(hdr->addr1), MAC2STR(hdr->addr2),
MAC2STR(hdr->addr3));
break;
case WLAN_FC_FROMDS:
wpa_printf(MSG_EXCESSIVE, "DATA %s%s%s FromDS DA=" MACSTR
" BSSID=" MACSTR " SA=" MACSTR,
data_stype(WLAN_FC_GET_STYPE(fc)),
fc & WLAN_FC_PWRMGT ? " PwrMgt" : "",
fc & WLAN_FC_ISWEP ? " Prot" : "",
MAC2STR(hdr->addr1), MAC2STR(hdr->addr2),
MAC2STR(hdr->addr3));
rx_data_bss(wt, hdr, qos, hdr->addr1, hdr->addr2,
data + hdrlen, len - hdrlen);
break;
case WLAN_FC_TODS:
wpa_printf(MSG_EXCESSIVE, "DATA %s%s%s ToDS BSSID=" MACSTR
" SA=" MACSTR " DA=" MACSTR,
data_stype(WLAN_FC_GET_STYPE(fc)),
fc & WLAN_FC_PWRMGT ? " PwrMgt" : "",
fc & WLAN_FC_ISWEP ? " Prot" : "",
MAC2STR(hdr->addr1), MAC2STR(hdr->addr2),
MAC2STR(hdr->addr3));
rx_data_bss(wt, hdr, qos, hdr->addr3, hdr->addr2,
data + hdrlen, len - hdrlen);
break;
case WLAN_FC_TODS | WLAN_FC_FROMDS:
wpa_printf(MSG_EXCESSIVE, "DATA %s%s%s WDS RA=" MACSTR " TA="
MACSTR " DA=" MACSTR " SA=" MACSTR,
data_stype(WLAN_FC_GET_STYPE(fc)),
fc & WLAN_FC_PWRMGT ? " PwrMgt" : "",
fc & WLAN_FC_ISWEP ? " Prot" : "",
MAC2STR(hdr->addr1), MAC2STR(hdr->addr2),
MAC2STR(hdr->addr3),
MAC2STR((const u8 *) (hdr + 1)));
break;
}
}
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