2823 lines
94 KiB
C
2823 lines
94 KiB
C
/* dot11decrypt.c
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*
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* Copyright (c) 2006 CACE Technologies, Davis (California)
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* All rights reserved.
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*
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* SPDX-License-Identifier: (BSD-3-Clause OR GPL-2.0-only)
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*/
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/****************************************************************************/
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/* File includes */
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#include "config.h"
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#include <glib.h>
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#include <wsutil/wsgcrypt.h>
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#include <wsutil/crc32.h>
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#include <wsutil/pint.h>
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#include <epan/proto.h> /* for DISSECTOR_ASSERT. */
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#include <epan/tvbuff.h>
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#include <epan/to_str.h>
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#include <epan/strutil.h>
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#include "dot11decrypt_system.h"
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#include "dot11decrypt_int.h"
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#include "dot11decrypt_debug.h"
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#include "wep-wpadefs.h"
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/****************************************************************************/
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static int Dot11DecryptGetKckLen(int akm);
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static int Dot11DecryptGetTkLen(int cipher);
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static int Dot11DecryptGetKekLen(int akm);
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static int Dot11DecryptGetPtkLen(int akm, int cipher);
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/****************************************************************************/
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/* Constant definitions */
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/* EAPOL definitions */
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/**
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* Length of the EAPOL-Key key confirmation key (KCK) used to calculate
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* MIC over EAPOL frame and validate an EAPOL packet (128 bits)
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*/
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#define DOT11DECRYPT_WPA_KCK_LEN 16
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/**
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*Offset of the Key MIC in the EAPOL packet body
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*/
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#define DOT11DECRYPT_WPA_MICKEY_OFFSET 77
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/**
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* Maximum length of the EAPOL packet (it depends on the maximum MAC
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* frame size)
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*/
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#define DOT11DECRYPT_WPA_MAX_EAPOL_LEN 4095
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/**
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* EAPOL Key Descriptor Version 1, used for all EAPOL-Key frames to and
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* from a STA when neither the group nor pairwise ciphers are CCMP for
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* Key Descriptor 1.
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* @note
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* Defined in 802.11i-2004, page 78
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*/
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#define DOT11DECRYPT_WPA_KEY_VER_NOT_CCMP 1
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/**
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* EAPOL Key Descriptor Version 2, used for all EAPOL-Key frames to and
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* from a STA when either the pairwise or the group cipher is AES-CCMP
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* for Key Descriptor 2.
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* /note
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* Defined in 802.11i-2004, page 78
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*/
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#define DOT11DECRYPT_WPA_KEY_VER_AES_CCMP 2
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/** Define EAPOL Key Descriptor type values: use 254 for WPA and 2 for WPA2 **/
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#define DOT11DECRYPT_RSN_WPA_KEY_DESCRIPTOR 254
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#define DOT11DECRYPT_RSN_WPA2_KEY_DESCRIPTOR 2
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/****************************************************************************/
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/****************************************************************************/
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/* Macro definitions */
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extern const UINT32 crc32_table[256];
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#define CRC(crc, ch) (crc = (crc >> 8) ^ crc32_table[(crc ^ (ch)) & 0xff])
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#define KCK_OFFSET(akm) (0)
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#define KEK_OFFSET(akm) ((KCK_OFFSET(akm) + Dot11DecryptGetKckLen(akm) / 8))
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#define TK_OFFSET(akm) ((KEK_OFFSET(akm) + Dot11DecryptGetKekLen(akm) / 8))
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#define DOT11DECRYPT_GET_KCK(ptk, akm) (ptk + KCK_OFFSET(akm))
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#define DOT11DECRYPT_GET_KEK(ptk, akm) (ptk + KEK_OFFSET(akm))
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#define DOT11DECRYPT_GET_TK_TKIP(ptk) (ptk + 32)
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#define DOT11DECRYPT_GET_TK(ptk, akm) (ptk + TK_OFFSET(akm))
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#define DOT11DECRYPT_IEEE80211_OUI(oui) (pntoh24(oui) == 0x000fac)
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/****************************************************************************/
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/****************************************************************************/
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/* Type definitions */
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/* Internal function prototype declarations */
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#ifdef __cplusplus
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extern "C" {
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#endif
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/**
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* It is a step of the PBKDF2 (specifically the PKCS #5 v2.0) defined in
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* the RFC 2898 to derive a key (used as PMK in WPA)
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* @param ppbytes [IN] pointer to a password (sequence of between 8 and
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* 63 ASCII encoded characters)
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* @param ssid [IN] pointer to the SSID string encoded in max 32 ASCII
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* encoded characters
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* @param iterations [IN] times to hash the password (4096 for WPA)
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* @param count [IN] ???
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* @param output [OUT] pointer to a preallocated buffer of
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* SHA1_DIGEST_LEN characters that will contain a part of the key
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*/
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static INT Dot11DecryptRsnaPwd2PskStep(
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const guint8 *ppbytes,
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const guint passLength,
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const CHAR *ssid,
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const size_t ssidLength,
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const INT iterations,
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const INT count,
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UCHAR *output)
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;
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/**
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* It calculates the passphrase-to-PSK mapping reccomanded for use with
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* RSNAs. This implementation uses the PBKDF2 method defined in the RFC
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* 2898.
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* @param passphrase [IN] pointer to a password (sequence of between 8 and
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* 63 ASCII encoded characters)
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* @param ssid [IN] pointer to the SSID string encoded in max 32 ASCII
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* encoded characters
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* @param output [OUT] calculated PSK (to use as PMK in WPA)
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* @note
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* Described in 802.11i-2004, page 165
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*/
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static INT Dot11DecryptRsnaPwd2Psk(
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const CHAR *passphrase,
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const CHAR *ssid,
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const size_t ssidLength,
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UCHAR *output)
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;
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static INT Dot11DecryptRsnaMng(
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UCHAR *decrypt_data,
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guint mac_header_len,
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guint *decrypt_len,
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PDOT11DECRYPT_KEY_ITEM key,
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DOT11DECRYPT_SEC_ASSOCIATION *sa)
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;
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static INT Dot11DecryptWepMng(
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PDOT11DECRYPT_CONTEXT ctx,
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UCHAR *decrypt_data,
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guint mac_header_len,
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guint *decrypt_len,
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PDOT11DECRYPT_KEY_ITEM key,
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DOT11DECRYPT_SEC_ASSOCIATION_ID *id)
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;
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static INT Dot11DecryptRsna4WHandshake(
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PDOT11DECRYPT_CONTEXT ctx,
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PDOT11DECRYPT_EAPOL_PARSED eapol_parsed,
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const guint8 *eapol_raw,
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DOT11DECRYPT_SEC_ASSOCIATION_ID *id,
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const guint tot_len);
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/**
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* It checks whether the specified key is corrected or not.
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* @note
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* For a standard WEP key the length will be changed to the standard
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* length, and the type changed in a generic WEP key.
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* @param key [IN] pointer to the key to validate
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* @return
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* - TRUE: the key contains valid fields and values
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* - FALSE: the key has some invalid field or value
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*/
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static INT Dot11DecryptValidateKey(
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PDOT11DECRYPT_KEY_ITEM key)
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;
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static INT Dot11DecryptRsnaMicCheck(
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PDOT11DECRYPT_EAPOL_PARSED eapol_parsed,
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UCHAR *eapol,
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USHORT eapol_len,
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UCHAR *KCK,
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USHORT key_ver,
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int akm)
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;
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static PDOT11DECRYPT_SEC_ASSOCIATION
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Dot11DecryptGetSa(
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PDOT11DECRYPT_CONTEXT ctx,
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const DOT11DECRYPT_SEC_ASSOCIATION_ID *id)
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;
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static INT Dot11DecryptGetSaAddress(
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const DOT11DECRYPT_MAC_FRAME_ADDR4 *frame,
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DOT11DECRYPT_SEC_ASSOCIATION_ID *id)
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;
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static const UCHAR * Dot11DecryptGetStaAddress(
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const DOT11DECRYPT_MAC_FRAME_ADDR4 *frame)
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;
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static const UCHAR * Dot11DecryptGetBssidAddress(
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const DOT11DECRYPT_MAC_FRAME_ADDR4 *frame)
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;
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static void
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Dot11DecryptDerivePtk(
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DOT11DECRYPT_SEC_ASSOCIATION *sa,
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const UCHAR *pmk,
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const UCHAR snonce[32],
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int key_version,
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int akm,
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int cipher);
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static void
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Dot11DecryptRsnaPrfX(
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DOT11DECRYPT_SEC_ASSOCIATION *sa,
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const UCHAR *pmk,
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const UCHAR snonce[32],
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const INT x, /* for TKIP 512, for CCMP 384 */
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UCHAR *ptk,
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int hash_algo);
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static void
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Dot11DecryptRsnaKdfX(
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DOT11DECRYPT_SEC_ASSOCIATION *sa,
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const UCHAR *pmk,
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const UCHAR snonce[32],
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const INT x,
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UCHAR *ptk,
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int hash_algo);
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/**
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* @param sa [IN/OUT] pointer to SA that will hold the key
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* @param data [IN] Frame
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* @param offset_rsne [IN] RSNE IE offset in the frame
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* @param offset_fte [IN] Fast BSS Transition IE offset in the frame
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* @param offset_timeout [IN] Timeout Interval IE offset in the frame
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* @param offset_link [IN] Link Identifier IE offset in the frame
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* @param action [IN] Tdls Action code (response or confirm)
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*
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* @return
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* DOT11DECRYPT_RET_SUCCESS if Key has been sucessfully derived (and MIC verified)
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* DOT11DECRYPT_RET_UNSUCCESS otherwise
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*/
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static INT
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Dot11DecryptTDLSDeriveKey(
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PDOT11DECRYPT_SEC_ASSOCIATION sa,
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const guint8 *data,
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guint offset_rsne,
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guint offset_fte,
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guint offset_timeout,
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guint offset_link,
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guint8 action)
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;
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#ifdef __cplusplus
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}
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#endif
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/****************************************************************************/
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/****************************************************************************/
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/* Exported function definitions */
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#ifdef __cplusplus
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extern "C" {
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#endif
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const guint8 broadcast_mac[] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
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#define TKIP_GROUP_KEY_LEN 32
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#define CCMP_GROUP_KEY_LEN 16
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typedef void (*DOT11DECRYPT_PTK_DERIVE_FUNC)(
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DOT11DECRYPT_SEC_ASSOCIATION *sa,
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const UCHAR *pmk,
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const UCHAR snonce[32],
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const INT x,
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UCHAR *ptk,
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int hash_algo);
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#define EAPOL_RSN_KEY_LEN 95
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/* Minimum possible key data size (at least one GTK KDE with CCMP key) */
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#define GROUP_KEY_MIN_LEN 8 + CCMP_GROUP_KEY_LEN
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/* Minimum possible group key msg size (group key msg using CCMP as cipher)*/
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#define GROUP_KEY_PAYLOAD_LEN_MIN \
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(EAPOL_RSN_KEY_LEN + GROUP_KEY_MIN_LEN)
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static void
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Dot11DecryptCopyKey(PDOT11DECRYPT_SEC_ASSOCIATION sa, PDOT11DECRYPT_KEY_ITEM key)
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{
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if (key!=NULL) {
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if (sa->key!=NULL)
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memcpy(key, sa->key, sizeof(DOT11DECRYPT_KEY_ITEM));
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else
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memset(key, 0, sizeof(DOT11DECRYPT_KEY_ITEM));
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key->KeyData.Wpa.PtkLen = sa->wpa.ptk_len;
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memcpy(key->KeyData.Wpa.Ptk, sa->wpa.ptk, sa->wpa.ptk_len);
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key->KeyData.Wpa.Akm = sa->wpa.akm;
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key->KeyData.Wpa.Cipher = sa->wpa.cipher;
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if (sa->wpa.key_ver==DOT11DECRYPT_WPA_KEY_VER_NOT_CCMP)
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key->KeyType=DOT11DECRYPT_KEY_TYPE_TKIP;
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else if (sa->wpa.key_ver == 0 || sa->wpa.key_ver == 3 ||
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sa->wpa.key_ver == DOT11DECRYPT_WPA_KEY_VER_AES_CCMP)
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{
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switch (sa->wpa.cipher) {
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case 1:
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key->KeyType = DOT11DECRYPT_KEY_TYPE_WEP_40;
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break;
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case 2:
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key->KeyType = DOT11DECRYPT_KEY_TYPE_TKIP;
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break;
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case 4:
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key->KeyType = DOT11DECRYPT_KEY_TYPE_CCMP;
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break;
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case 5:
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key->KeyType = DOT11DECRYPT_KEY_TYPE_WEP_104;
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break;
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case 8:
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key->KeyType = DOT11DECRYPT_KEY_TYPE_GCMP;
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break;
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case 9:
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key->KeyType = DOT11DECRYPT_KEY_TYPE_GCMP_256;
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break;
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case 10:
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key->KeyType = DOT11DECRYPT_KEY_TYPE_CCMP_256;
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break;
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default:
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key->KeyType = DOT11DECRYPT_KEY_TYPE_UNKNOWN;
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break;
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/* NOT SUPPORTED YET
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case 3: Reserved
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case 6: BIP-CMAC-128
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case 7: Group addressed traffic not allowed
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case 11: BIP-GMAC-128
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case 12: BIP-GMAC-256
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case 13: BIP-CMAC-256 */
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}
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}
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}
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}
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static guint8*
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Dot11DecryptRc4KeyData(const guint8 *decryption_key, guint decryption_key_len,
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const guint8 *encrypted_keydata, guint encrypted_keydata_len)
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{
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gcry_cipher_hd_t rc4_handle;
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guint8 dummy[256] = { 0 };
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guint8 *decrypted_key = NULL;
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if (gcry_cipher_open (&rc4_handle, GCRY_CIPHER_ARCFOUR, GCRY_CIPHER_MODE_STREAM, 0)) {
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return NULL;
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}
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if (gcry_cipher_setkey(rc4_handle, decryption_key, decryption_key_len)) {
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gcry_cipher_close(rc4_handle);
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return NULL;
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}
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decrypted_key = (guint8 *)g_memdup(encrypted_keydata, encrypted_keydata_len);
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if (!decrypted_key) {
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gcry_cipher_close(rc4_handle);
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return NULL;
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}
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/* Do dummy 256 iterations of the RC4 algorithm (per 802.11i, Draft 3.0, p. 97 line 6) */
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gcry_cipher_decrypt(rc4_handle, dummy, 256, NULL, 0);
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gcry_cipher_decrypt(rc4_handle, decrypted_key, encrypted_keydata_len, NULL, 0);
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gcry_cipher_close(rc4_handle);
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return decrypted_key;
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}
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static int
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AES_unwrap(
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const guint8 *kek,
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guint16 kek_len,
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const guint8 *cipher_text,
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guint16 cipher_len,
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guint8 *output,
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guint16 *output_len)
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{
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#if GCRYPT_VERSION_NUMBER >= 0x010500 /* 1.5.0 */
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gcry_cipher_hd_t handle;
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if (kek == NULL || cipher_len < 16 || cipher_text == NULL) {
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return 1; /* "should not happen" */
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}
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if (gcry_cipher_open(&handle, GCRY_CIPHER_AES, GCRY_CIPHER_MODE_AESWRAP, 0)) {
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return 1;
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}
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if (gcry_cipher_setkey(handle, kek, kek_len)) {
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gcry_cipher_close(handle);
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return 1;
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}
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if (gcry_cipher_decrypt(handle, output, cipher_len - 8, cipher_text, cipher_len)) {
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gcry_cipher_close(handle);
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return 1;
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}
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*output_len = cipher_len - 8;
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gcry_cipher_close(handle);
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return 0;
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#else /* libcgrypt AES unwrap function not available */
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/* Legacy implementation moved from dot11decrypt_rijindael.c */
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/* Based on RFC 3394 and NIST AES Key Wrap Specification pseudo-code. */
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UCHAR a[8], b[16];
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UCHAR *r;
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gint16 i, j, n;
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gcry_cipher_hd_t rijndael_handle;
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if (kek == NULL || cipher_len < 16 || cipher_text == NULL) {
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return 1; /* "should not happen" */
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}
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/* Initialize variables */
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memset(output, 0, cipher_len - 8);
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n = (cipher_len/8)-1; /* the algorithm works on 64-bits at a time */
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memcpy(a, cipher_text, 8);
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r = output;
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memcpy(r, cipher_text+8, cipher_len - 8);
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/* Compute intermediate values */
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if (gcry_cipher_open(&rijndael_handle, GCRY_CIPHER_AES, GCRY_CIPHER_MODE_ECB, 0)) {
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return 1;
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}
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if (gcry_cipher_setkey(rijndael_handle, kek, kek_len)) {
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gcry_cipher_close(rijndael_handle);
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return 1;
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}
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for (j=5; j >= 0; --j){
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r = output + (n - 1) * 8;
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/* DEBUG_DUMP("r1", (r-8), 8); */
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/* DEBUG_DUMP("r2", r, 8); */
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for (i = n; i >= 1; --i){
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UINT16 t = (n*j) + i;
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/* DEBUG_DUMP("a", a, 8); */
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memcpy(b, a, 8);
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b[7] ^= t;
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/* DEBUG_DUMP("a plus t", b, 8); */
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memcpy(b+8, r, 8);
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gcry_cipher_decrypt(rijndael_handle, b, 16, NULL, 0);
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/* DEBUG_DUMP("aes decrypt", b, 16) */
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memcpy(a,b,8);
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memcpy(r, b+8, 8);
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r -= 8;
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}
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}
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gcry_cipher_close(rijndael_handle);
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/* DEBUG_DUMP("a", a, 8); */
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/* DEBUG_DUMP("output", output, cipher_len - 8); */
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*output_len = cipher_len - 8;
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return 0;
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#endif
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}
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INT
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Dot11DecryptDecryptKeyData(PDOT11DECRYPT_CONTEXT ctx,
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PDOT11DECRYPT_EAPOL_PARSED eapol_parsed,
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const UCHAR bssid[DOT11DECRYPT_MAC_LEN],
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const UCHAR sta[DOT11DECRYPT_MAC_LEN],
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UCHAR *decrypted_data, guint *decrypted_len,
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PDOT11DECRYPT_KEY_ITEM key)
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{
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guint8 key_version;
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const guint8 *key_data;
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guint16 key_bytes_len = 0; /* Length of the total key data field */
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DOT11DECRYPT_SEC_ASSOCIATION_ID id;
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PDOT11DECRYPT_SEC_ASSOCIATION sa;
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|
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/* search for a cached Security Association for current BSSID and AP */
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memcpy(id.bssid, bssid, DOT11DECRYPT_MAC_LEN);
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memcpy(id.sta, sta, DOT11DECRYPT_MAC_LEN);
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sa = Dot11DecryptGetSa(ctx, &id);
|
|
if (sa == NULL || !sa->validKey) {
|
|
DEBUG_PRINT_LINE("No valid SA for BSSID found", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
/* Decrypt GTK using KEK portion of PTK */
|
|
guint8 *decryption_key = DOT11DECRYPT_GET_KEK(sa->wpa.ptk, sa->wpa.akm);
|
|
guint decryption_key_len = Dot11DecryptGetKekLen(sa->wpa.akm) / 8;
|
|
|
|
/* We skip verifying the MIC of the key. If we were implementing a WPA supplicant we'd want to verify, but for a sniffer it's not needed. */
|
|
|
|
/* Preparation for decrypting the group key - determine group key data length */
|
|
/* depending on whether the pairwise key is TKIP or AES encryption key */
|
|
key_version = eapol_parsed->key_version;
|
|
if (key_version == DOT11DECRYPT_WPA_KEY_VER_NOT_CCMP){
|
|
/* TKIP */
|
|
key_bytes_len = eapol_parsed->key_len;
|
|
}else if (key_version == DOT11DECRYPT_WPA_KEY_VER_AES_CCMP){
|
|
/* AES */
|
|
key_bytes_len = eapol_parsed->key_data_len;
|
|
|
|
/* AES keys must be at least 128 bits = 16 bytes. */
|
|
if (key_bytes_len < 16) {
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
} else {
|
|
/* XXX Ideally group cipher suite type from EAPOL message 2 of 4 should be used to */
|
|
/* determine key size. As we currently have no way to do this lookup check that key */
|
|
/* is at least 16 bytes (IEEE802.11-2016 Table 12-4 Cipher suite key lengths) */
|
|
key_bytes_len = eapol_parsed->key_data_len;
|
|
|
|
if (key_bytes_len < 16) {
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
}
|
|
|
|
if ((key_bytes_len < GROUP_KEY_MIN_LEN) ||
|
|
(eapol_parsed->len < EAPOL_RSN_KEY_LEN) ||
|
|
(key_bytes_len > eapol_parsed->len - EAPOL_RSN_KEY_LEN)) {
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
/* Encrypted key is in the information element field of the EAPOL key packet */
|
|
key_data = eapol_parsed->key_data;
|
|
|
|
DEBUG_DUMP("Encrypted Broadcast key:", key_data, key_bytes_len);
|
|
DEBUG_DUMP("KeyIV:", eapol_parsed->key_iv, 16);
|
|
DEBUG_DUMP("decryption_key:", decryption_key, decryption_key_len);
|
|
|
|
/* As we have no concept of the prior association request at this point, we need to deduce the */
|
|
/* group key cipher from the length of the key bytes. In WPA this is straightforward as the */
|
|
/* keybytes just contain the GTK, and the GTK is only in the group handshake, NOT the M3. */
|
|
/* In WPA2 its a little more tricky as the M3 keybytes contain an RSN_IE, but the group handshake */
|
|
/* does not. Also there are other (variable length) items in the keybytes which we need to account */
|
|
/* for to determine the true key length, and thus the group cipher. */
|
|
|
|
if (key_version == DOT11DECRYPT_WPA_KEY_VER_NOT_CCMP){
|
|
/* TKIP key */
|
|
/* Per 802.11i, Draft 3.0 spec, section 8.5.2, p. 97, line 4-8, */
|
|
/* group key is decrypted using RC4. Concatenate the IV with the 16 byte EK (PTK+16) to get the decryption key */
|
|
guint8 new_key[32];
|
|
guint8 *data;
|
|
|
|
/* The WPA group key just contains the GTK bytes so deducing the type is straightforward */
|
|
/* Note - WPA M3 doesn't contain a group key so we'll only be here for the group handshake */
|
|
sa->wpa.key_ver = (key_bytes_len >=TKIP_GROUP_KEY_LEN)?DOT11DECRYPT_WPA_KEY_VER_NOT_CCMP:DOT11DECRYPT_WPA_KEY_VER_AES_CCMP;
|
|
|
|
/* Build the full decryption key based on the IV and part of the pairwise key */
|
|
memcpy(new_key, eapol_parsed->key_iv, 16);
|
|
memcpy(new_key+16, decryption_key, 16);
|
|
DEBUG_DUMP("FullDecrKey:", new_key, 32);
|
|
data = Dot11DecryptRc4KeyData(new_key, 32, key_data, key_bytes_len);
|
|
if (!data) {
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
memcpy(decrypted_data, data, key_bytes_len);
|
|
g_free(data);
|
|
} else {
|
|
/* Ideally AKM from EAPOL message 2 of 4 should be used to determine Key-wrap algoritm to use */
|
|
/* Though fortunately IEEE802.11-2016 Table 12-8 state that all AKMs use "NIST AES Key Wrap" */
|
|
/* algorithm so no AKM lookup is needed. */
|
|
|
|
/* Unwrap the key; the result is key_bytes_len in length */
|
|
if (AES_unwrap(decryption_key, decryption_key_len, key_data, key_bytes_len,
|
|
decrypted_data, &key_bytes_len)) {
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
}
|
|
|
|
Dot11DecryptCopyKey(sa, key);
|
|
*decrypted_len = key_bytes_len;
|
|
return DOT11DECRYPT_RET_SUCCESS;
|
|
}
|
|
|
|
/**
|
|
* @param ctx [IN] pointer to the current context
|
|
* @param id [IN] id of the association (composed by BSSID and MAC of
|
|
* the station)
|
|
* @return a pointer the the requested SA. NULL if it doesn't exist.
|
|
*/
|
|
static PDOT11DECRYPT_SEC_ASSOCIATION
|
|
Dot11DecryptGetSa(
|
|
PDOT11DECRYPT_CONTEXT ctx,
|
|
const DOT11DECRYPT_SEC_ASSOCIATION_ID *id)
|
|
{
|
|
return (DOT11DECRYPT_SEC_ASSOCIATION *)g_hash_table_lookup(ctx->sa_hash, id);
|
|
}
|
|
|
|
static PDOT11DECRYPT_SEC_ASSOCIATION
|
|
Dot11DecryptNewSa(const DOT11DECRYPT_SEC_ASSOCIATION_ID *id)
|
|
{
|
|
PDOT11DECRYPT_SEC_ASSOCIATION sa = g_new0(DOT11DECRYPT_SEC_ASSOCIATION, 1);
|
|
if (sa != NULL) {
|
|
sa->saId = *id;
|
|
}
|
|
return sa;
|
|
}
|
|
|
|
static DOT11DECRYPT_SEC_ASSOCIATION *
|
|
Dot11DecryptPrependSa(
|
|
DOT11DECRYPT_SEC_ASSOCIATION *existing_sa,
|
|
DOT11DECRYPT_SEC_ASSOCIATION *new_sa)
|
|
{
|
|
DOT11DECRYPT_SEC_ASSOCIATION tmp_sa;
|
|
|
|
/* Add new SA first in list, but copy by value into existing record
|
|
* so that sa_hash need not be updated with new value */
|
|
tmp_sa = *existing_sa;
|
|
*existing_sa = *new_sa;
|
|
*new_sa = tmp_sa;
|
|
existing_sa->next = new_sa;
|
|
return existing_sa;
|
|
}
|
|
|
|
/* Add SA, keep existing (if any). Return pointer to newly inserted (first) SA */
|
|
static PDOT11DECRYPT_SEC_ASSOCIATION
|
|
Dot11DecryptAddSa(
|
|
PDOT11DECRYPT_CONTEXT ctx,
|
|
const DOT11DECRYPT_SEC_ASSOCIATION_ID *id,
|
|
DOT11DECRYPT_SEC_ASSOCIATION *sa)
|
|
{
|
|
DOT11DECRYPT_SEC_ASSOCIATION *existing_sa = Dot11DecryptGetSa(ctx, id);
|
|
if (existing_sa != NULL) {
|
|
sa = Dot11DecryptPrependSa(existing_sa, sa);
|
|
} else {
|
|
void *key = g_memdup(id, sizeof(DOT11DECRYPT_SEC_ASSOCIATION_ID));
|
|
g_hash_table_insert(ctx->sa_hash, key, sa);
|
|
}
|
|
return sa;
|
|
}
|
|
|
|
int
|
|
Dot11DecryptGetKCK(const PDOT11DECRYPT_KEY_ITEM key, const guint8 **kck)
|
|
{
|
|
if (!key || !kck) {
|
|
return 0;
|
|
}
|
|
*kck = DOT11DECRYPT_GET_KCK(key->KeyData.Wpa.Ptk, key->KeyData.Wpa.Akm);
|
|
return Dot11DecryptGetKckLen(key->KeyData.Wpa.Akm) / 8;
|
|
}
|
|
|
|
int
|
|
Dot11DecryptGetKEK(const PDOT11DECRYPT_KEY_ITEM key, const guint8 **kek)
|
|
{
|
|
if (!key || !kek) {
|
|
return 0;
|
|
}
|
|
*kek = DOT11DECRYPT_GET_KEK(key->KeyData.Wpa.Ptk, key->KeyData.Wpa.Akm);
|
|
return Dot11DecryptGetKekLen(key->KeyData.Wpa.Akm) / 8;
|
|
}
|
|
|
|
int
|
|
Dot11DecryptGetTK(const PDOT11DECRYPT_KEY_ITEM key, const guint8 **tk)
|
|
{
|
|
int len;
|
|
if (!key || !tk) {
|
|
return 0;
|
|
}
|
|
if (key->KeyType == DOT11DECRYPT_KEY_TYPE_TKIP) {
|
|
*tk = DOT11DECRYPT_GET_TK_TKIP(key->KeyData.Wpa.Ptk);
|
|
len = 16;
|
|
} else {
|
|
*tk = DOT11DECRYPT_GET_TK(key->KeyData.Wpa.Ptk, key->KeyData.Wpa.Akm);
|
|
len = Dot11DecryptGetTkLen(key->KeyData.Wpa.Cipher) / 8;
|
|
}
|
|
return len;
|
|
}
|
|
|
|
int
|
|
Dot11DecryptGetGTK(const PDOT11DECRYPT_KEY_ITEM key, const guint8 **gtk)
|
|
{
|
|
int len;
|
|
if (!key || !gtk) {
|
|
return 0;
|
|
}
|
|
|
|
/* GTK is stored in PTK at offset 32. See comment in Dot11DecryptCopyBroadcastKey */
|
|
*gtk = key->KeyData.Wpa.Ptk + 32;
|
|
if (key->KeyType == DOT11DECRYPT_KEY_TYPE_TKIP) {
|
|
len = 16;
|
|
} else {
|
|
len = Dot11DecryptGetTkLen(key->KeyData.Wpa.Cipher) / 8;
|
|
}
|
|
return len;
|
|
}
|
|
|
|
INT Dot11DecryptScanTdlsForKeys(
|
|
PDOT11DECRYPT_CONTEXT ctx,
|
|
const guint8 *data,
|
|
const guint tot_len)
|
|
{
|
|
guint offset = 0;
|
|
guint tot_len_left = tot_len;
|
|
DOT11DECRYPT_SEC_ASSOCIATION_ID id;
|
|
PDOT11DECRYPT_SEC_ASSOCIATION sa;
|
|
const guint8 *initiator, *responder;
|
|
guint8 action;
|
|
guint status, offset_rsne = 0, offset_fte = 0, offset_link = 0, offset_timeout = 0;
|
|
DEBUG_PRINT_LINE("Authentication: TDLS Action Frame", DEBUG_LEVEL_3);
|
|
|
|
/* TDLS payload contains a TDLS Action field (802.11-2016 9.6.13) */
|
|
|
|
/* check if the packet is a TDLS response or confirm */
|
|
if (tot_len_left < 1) {
|
|
DEBUG_PRINT_LINE("Not EAPOL-Key", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
action = data[offset];
|
|
if (action != 1 && action != 2) {
|
|
DEBUG_PRINT_LINE("Not Response nor confirm", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
offset++;
|
|
tot_len_left--;
|
|
|
|
/* Check for SUCCESS (0) or SUCCESS_POWER_SAVE_MODE (85) Status Code */
|
|
if (tot_len_left < 5) {
|
|
DEBUG_PRINT_LINE("Not EAPOL-Key", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
status=pntoh16(data + offset);
|
|
if (status != 0 && status != 85) {
|
|
DEBUG_PRINT_LINE("TDLS setup not successful", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
|
|
/* skip Token + capabilities */
|
|
offset += 5;
|
|
|
|
/* search for RSN, Fast BSS Transition, Link Identifier and Timeout Interval IEs */
|
|
|
|
while(offset < (tot_len - 2)) {
|
|
guint8 element_id = data[offset];
|
|
guint8 length = data[offset + 1];
|
|
guint min_length = length;
|
|
switch (element_id) {
|
|
case 48: /* RSN (802.11-2016 9.4.2.35) */
|
|
offset_rsne = offset;
|
|
min_length = 1;
|
|
break;
|
|
case 55: /* FTE (802.11-2016 9.4.2.48) */
|
|
offset_fte = offset;
|
|
/* Plus variable length optional parameter(s) */
|
|
min_length = 2 + 16 + 32 + 32;
|
|
break;
|
|
case 56: /* Timeout Interval (802.11-2016 9.4.2.49) */
|
|
offset_timeout = offset;
|
|
min_length = 1 + 4;
|
|
break;
|
|
case 101: /* Link Identifier (802.11-2016 9.4.2.62) */
|
|
offset_link = offset;
|
|
min_length = 6 + 6 + 6;
|
|
break;
|
|
}
|
|
|
|
if (length < min_length || tot_len < offset + 2 + length) {
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
offset += 2 + length;
|
|
}
|
|
|
|
if (offset_rsne == 0 || offset_fte == 0 ||
|
|
offset_timeout == 0 || offset_link == 0)
|
|
{
|
|
DEBUG_PRINT_LINE("Cannot Find all necessary IEs", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
|
|
DEBUG_PRINT_LINE("Found RSNE/Fast BSS/Timeout Interval/Link IEs", DEBUG_LEVEL_3);
|
|
|
|
/* Will create a Security Association between 2 STA. Need to get both MAC address */
|
|
initiator = &data[offset_link + 8];
|
|
responder = &data[offset_link + 14];
|
|
|
|
if (memcmp(initiator, responder, DOT11DECRYPT_MAC_LEN) < 0) {
|
|
memcpy(id.sta, initiator, DOT11DECRYPT_MAC_LEN);
|
|
memcpy(id.bssid, responder, DOT11DECRYPT_MAC_LEN);
|
|
} else {
|
|
memcpy(id.sta, responder, DOT11DECRYPT_MAC_LEN);
|
|
memcpy(id.bssid, initiator, DOT11DECRYPT_MAC_LEN);
|
|
}
|
|
|
|
/* Check if already derived this key */
|
|
sa = Dot11DecryptGetSa(ctx, &id);
|
|
PDOT11DECRYPT_SEC_ASSOCIATION iter_sa;
|
|
for (iter_sa = sa; iter_sa != NULL; iter_sa = iter_sa->next) {
|
|
if (iter_sa->validKey &&
|
|
memcmp(iter_sa->wpa.nonce, data + offset_fte + 52,
|
|
DOT11DECRYPT_WPA_NONCE_LEN) == 0)
|
|
{
|
|
/* Already have valid key for this SA, no need to redo key derivation */
|
|
return DOT11DECRYPT_RET_SUCCESS_HANDSHAKE;
|
|
}
|
|
}
|
|
/* We are opening a new session with the same two STA (previous sa will be kept if any) */
|
|
sa = Dot11DecryptNewSa(&id);
|
|
if (sa == NULL) {
|
|
return DOT11DECRYPT_RET_REQ_DATA;
|
|
}
|
|
if (Dot11DecryptTDLSDeriveKey(sa, data, offset_rsne, offset_fte,
|
|
offset_timeout, offset_link, action) == DOT11DECRYPT_RET_SUCCESS) {
|
|
Dot11DecryptAddSa(ctx, &id, sa);
|
|
return DOT11DECRYPT_RET_SUCCESS_HANDSHAKE;
|
|
}
|
|
g_free(sa);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
|
|
static INT
|
|
Dot11DecryptCopyBroadcastKey(
|
|
PDOT11DECRYPT_CONTEXT ctx,
|
|
const PDOT11DECRYPT_EAPOL_PARSED eapol_parsed,
|
|
const DOT11DECRYPT_SEC_ASSOCIATION_ID *id)
|
|
{
|
|
DOT11DECRYPT_SEC_ASSOCIATION_ID broadcast_id;
|
|
DOT11DECRYPT_SEC_ASSOCIATION *sa;
|
|
DOT11DECRYPT_SEC_ASSOCIATION *broadcast_sa;
|
|
|
|
if (!eapol_parsed->gtk || eapol_parsed->gtk_len == 0) {
|
|
DEBUG_PRINT_LINE("No broadcast key found", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
if (eapol_parsed->gtk_len > DOT11DECRYPT_WPA_PTK_MAX_LEN - 32) {
|
|
DEBUG_PRINT_LINE("Broadcast key too large", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
|
|
sa = Dot11DecryptGetSa(ctx, id);
|
|
if (sa == NULL) {
|
|
DEBUG_PRINT_LINE("No SA for BSSID found", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
|
|
/* Broadcast SA for the current BSSID */
|
|
memcpy(broadcast_id.bssid, id->bssid, DOT11DECRYPT_MAC_LEN);
|
|
memcpy(broadcast_id.sta, broadcast_mac, DOT11DECRYPT_MAC_LEN);
|
|
|
|
broadcast_sa = Dot11DecryptNewSa(&broadcast_id);
|
|
if (broadcast_sa == NULL) {
|
|
DEBUG_PRINT_LINE("Failed to alloc broadcast sa", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
|
|
/* Retrieve AKMS / cipher etc from handshake message 2 */
|
|
|
|
broadcast_sa->wpa.key_ver = sa->wpa.key_ver;
|
|
broadcast_sa->wpa.akm = sa->wpa.akm;
|
|
broadcast_sa->wpa.cipher = sa->wpa.tmp_group_cipher;
|
|
broadcast_sa->wpa.ptk_len = sa->wpa.ptk_len;
|
|
broadcast_sa->validKey = TRUE;
|
|
DEBUG_DUMP("Broadcast key:", eapol_parsed->gtk, eapol_parsed->gtk_len);
|
|
|
|
/* Since this is a GTK and its size is only 32 bytes (vs. the 64 byte size of a PTK),
|
|
* we fake it and put it in at a 32-byte offset so the Dot11DecryptRsnaMng() function
|
|
* will extract the right piece of the GTK for decryption. (The first 16 bytes of the
|
|
* GTK are used for decryption.) */
|
|
memset(broadcast_sa->wpa.ptk, 0, sizeof(broadcast_sa->wpa.ptk));
|
|
memcpy(broadcast_sa->wpa.ptk + 32, eapol_parsed->gtk, eapol_parsed->gtk_len);
|
|
Dot11DecryptAddSa(ctx, &broadcast_id, broadcast_sa);
|
|
return DOT11DECRYPT_RET_SUCCESS_HANDSHAKE;
|
|
}
|
|
|
|
static int
|
|
Dot11DecryptGroupHandshake(
|
|
PDOT11DECRYPT_CONTEXT ctx,
|
|
PDOT11DECRYPT_EAPOL_PARSED eapol_parsed,
|
|
const DOT11DECRYPT_SEC_ASSOCIATION_ID *id,
|
|
const guint tot_len)
|
|
{
|
|
|
|
if (GROUP_KEY_PAYLOAD_LEN_MIN > tot_len) {
|
|
DEBUG_PRINT_LINE("Message too short for Group Key", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
if (eapol_parsed->msg_type != DOT11DECRYPT_HS_MSG_TYPE_GHS_1){
|
|
|
|
DEBUG_PRINT_LINE("Not Group handshake message 1", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
return Dot11DecryptCopyBroadcastKey(ctx, eapol_parsed, id);
|
|
}
|
|
|
|
INT Dot11DecryptScanEapolForKeys(
|
|
PDOT11DECRYPT_CONTEXT ctx,
|
|
PDOT11DECRYPT_EAPOL_PARSED eapol_parsed,
|
|
const guint8 *eapol_raw,
|
|
const guint tot_len,
|
|
const UCHAR bssid[DOT11DECRYPT_MAC_LEN],
|
|
const UCHAR sta[DOT11DECRYPT_MAC_LEN])
|
|
{
|
|
DOT11DECRYPT_SEC_ASSOCIATION_ID id;
|
|
|
|
/* Callers provide these guarantees, so let's make them explicit. */
|
|
DISSECTOR_ASSERT(tot_len <= DOT11DECRYPT_EAPOL_MAX_LEN);
|
|
|
|
DEBUG_PRINT_LINE("Authentication: EAPOL packet", DEBUG_LEVEL_3);
|
|
|
|
/* check if the key descriptor type is valid (IEEE 802.1X-2004, pg. 27) */
|
|
if (/*eapol_parsed->key_type != 0x1 &&*/ /* RC4 Key Descriptor Type (deprecated) */
|
|
eapol_parsed->key_type != DOT11DECRYPT_RSN_WPA2_KEY_DESCRIPTOR && /* IEEE 802.11 Key Descriptor Type (WPA2) */
|
|
eapol_parsed->key_type != DOT11DECRYPT_RSN_WPA_KEY_DESCRIPTOR) /* 254 = RSN_KEY_DESCRIPTOR - WPA, */
|
|
{
|
|
DEBUG_PRINT_LINE("Not valid key descriptor type", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
|
|
/* search for a cached Security Association for current BSSID and AP */
|
|
memcpy(id.bssid, bssid, DOT11DECRYPT_MAC_LEN);
|
|
memcpy(id.sta, sta, DOT11DECRYPT_MAC_LEN);
|
|
|
|
switch (eapol_parsed->msg_type) {
|
|
case DOT11DECRYPT_HS_MSG_TYPE_4WHS_1:
|
|
case DOT11DECRYPT_HS_MSG_TYPE_4WHS_2:
|
|
case DOT11DECRYPT_HS_MSG_TYPE_4WHS_3:
|
|
case DOT11DECRYPT_HS_MSG_TYPE_4WHS_4:
|
|
return Dot11DecryptRsna4WHandshake(ctx, eapol_parsed, eapol_raw,
|
|
&id, tot_len);
|
|
case DOT11DECRYPT_HS_MSG_TYPE_GHS_1:
|
|
return Dot11DecryptGroupHandshake(ctx, eapol_parsed, &id, tot_len);
|
|
case DOT11DECRYPT_HS_MSG_TYPE_INVALID:
|
|
default:
|
|
DEBUG_PRINT_LINE("Invalid message type", DEBUG_LEVEL_3);
|
|
break;
|
|
}
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
|
|
static int
|
|
Dot11DecryptGetNbrOfTkKeys(PDOT11DECRYPT_CONTEXT ctx)
|
|
{
|
|
int nbr = 0;
|
|
for (size_t i = 0; i < ctx->keys_nr; i++) {
|
|
if (ctx->keys[i].KeyType == DOT11DECRYPT_KEY_TYPE_TK) {
|
|
nbr++;
|
|
}
|
|
}
|
|
return nbr;
|
|
}
|
|
|
|
static int
|
|
Dot11DecryptUsingUserTk(
|
|
PDOT11DECRYPT_CONTEXT ctx,
|
|
UCHAR *decrypt_data,
|
|
guint mac_header_len,
|
|
guint *decrypt_len,
|
|
DOT11DECRYPT_SEC_ASSOCIATION_ID *id,
|
|
DOT11DECRYPT_KEY_ITEM *used_key)
|
|
{
|
|
int ret = DOT11DECRYPT_RET_REQ_DATA;
|
|
DOT11DECRYPT_SEC_ASSOCIATION *sa = Dot11DecryptNewSa(id);
|
|
DOT11DECRYPT_KEY_ITEM *key;
|
|
if (sa == NULL) {
|
|
return ret;
|
|
}
|
|
|
|
sa->wpa.akm = 2;
|
|
sa->validKey = TRUE;
|
|
|
|
/* Try decrypt packet with all user TKs applicable ciphers */
|
|
for (size_t key_index = 0; key_index < ctx->keys_nr; key_index++) {
|
|
key = &ctx->keys[key_index];
|
|
if (key->KeyType != DOT11DECRYPT_KEY_TYPE_TK) {
|
|
continue;
|
|
}
|
|
int ciphers_to_try[4] = { 0 };
|
|
switch (key->Tk.Len) {
|
|
case DOT11DECRYPT_WEP_40_KEY_LEN:
|
|
case DOT11DECRYPT_WEP_104_KEY_LEN:
|
|
/* TBD implement */
|
|
continue;
|
|
case 256 / 8:
|
|
ciphers_to_try[0] = 9; /* GCMP-256 */
|
|
ciphers_to_try[1] = 10; /* CCMP-256 */
|
|
break;
|
|
case 128 / 8:
|
|
ciphers_to_try[0] = 4; /* CCMP-128 */
|
|
ciphers_to_try[1] = 8; /* GCMP-128 */
|
|
ciphers_to_try[2] = 2; /* TKIP */
|
|
break;
|
|
default:
|
|
continue;
|
|
}
|
|
|
|
sa->key = key;
|
|
|
|
for (int i = 0; ciphers_to_try[i] != 0; i++) {
|
|
sa->wpa.cipher = ciphers_to_try[i];
|
|
if (sa->wpa.cipher == 2 /* TKIP */) {
|
|
sa->wpa.key_ver = 1;
|
|
memcpy(DOT11DECRYPT_GET_TK_TKIP(sa->wpa.ptk),
|
|
key->Tk.Tk, key->Tk.Len);
|
|
} else {
|
|
sa->wpa.key_ver = 2;
|
|
sa->wpa.akm = 2;
|
|
memcpy(DOT11DECRYPT_GET_TK(sa->wpa.ptk, sa->wpa.akm),
|
|
key->Tk.Tk, key->Tk.Len);
|
|
}
|
|
sa->wpa.ptk_len = Dot11DecryptGetPtkLen(sa->wpa.akm, sa->wpa.cipher) / 8;
|
|
ret = Dot11DecryptRsnaMng(decrypt_data, mac_header_len, decrypt_len, used_key, sa);
|
|
if (ret == DOT11DECRYPT_RET_SUCCESS) {
|
|
/* Successfully decrypted using user TK. Add SA formed from user TK so that
|
|
* subsequent frames can be decrypted much faster using normal code path
|
|
* without trying each and every user TK entered.
|
|
*/
|
|
Dot11DecryptAddSa(ctx, id, sa);
|
|
return ret;
|
|
}
|
|
}
|
|
}
|
|
g_free(sa);
|
|
return ret;
|
|
}
|
|
|
|
INT Dot11DecryptDecryptPacket(
|
|
PDOT11DECRYPT_CONTEXT ctx,
|
|
const guint8 *data,
|
|
const guint mac_header_len,
|
|
const guint tot_len,
|
|
UCHAR *decrypt_data,
|
|
guint *decrypt_len,
|
|
PDOT11DECRYPT_KEY_ITEM key)
|
|
{
|
|
DOT11DECRYPT_SEC_ASSOCIATION_ID id;
|
|
DISSECTOR_ASSERT(decrypt_data);
|
|
DISSECTOR_ASSERT(decrypt_len);
|
|
|
|
#ifdef DOT11DECRYPT_DEBUG
|
|
#define MSGBUF_LEN 255
|
|
CHAR msgbuf[MSGBUF_LEN];
|
|
#endif
|
|
|
|
if (decrypt_len) {
|
|
*decrypt_len = 0;
|
|
}
|
|
if (ctx==NULL) {
|
|
DEBUG_PRINT_LINE("NULL context", DEBUG_LEVEL_5);
|
|
return DOT11DECRYPT_RET_REQ_DATA;
|
|
}
|
|
if (data==NULL || tot_len==0) {
|
|
DEBUG_PRINT_LINE("NULL data or length=0", DEBUG_LEVEL_5);
|
|
return DOT11DECRYPT_RET_REQ_DATA;
|
|
}
|
|
|
|
/* check correct packet size, to avoid wrong elaboration of encryption algorithms */
|
|
if (tot_len < (UINT)(mac_header_len+DOT11DECRYPT_CRYPTED_DATA_MINLEN)) {
|
|
DEBUG_PRINT_LINE("minimum length violated", DEBUG_LEVEL_5);
|
|
return DOT11DECRYPT_RET_WRONG_DATA_SIZE;
|
|
}
|
|
|
|
/* Assume that the decrypt_data field is no more than this size. */
|
|
if (tot_len > DOT11DECRYPT_MAX_CAPLEN) {
|
|
DEBUG_PRINT_LINE("length too large", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
/* get STA/BSSID address */
|
|
if (Dot11DecryptGetSaAddress((const DOT11DECRYPT_MAC_FRAME_ADDR4 *)(data), &id) != DOT11DECRYPT_RET_SUCCESS) {
|
|
DEBUG_PRINT_LINE("STA/BSSID not found", DEBUG_LEVEL_5);
|
|
return DOT11DECRYPT_RET_REQ_DATA;
|
|
}
|
|
|
|
/* check if data is encrypted (use the WEP bit in the Frame Control field) */
|
|
if (DOT11DECRYPT_WEP(data[1])==0) {
|
|
return DOT11DECRYPT_RET_NO_DATA_ENCRYPTED;
|
|
}
|
|
PDOT11DECRYPT_SEC_ASSOCIATION sa;
|
|
|
|
/* create new header and data to modify */
|
|
*decrypt_len = tot_len;
|
|
memcpy(decrypt_data, data, *decrypt_len);
|
|
|
|
/* encrypted data */
|
|
DEBUG_PRINT_LINE("Encrypted data", DEBUG_LEVEL_3);
|
|
|
|
/* check the Extension IV to distinguish between WEP encryption and WPA encryption */
|
|
/* refer to IEEE 802.11i-2004, 8.2.1.2, pag.35 for WEP, */
|
|
/* IEEE 802.11i-2004, 8.3.2.2, pag. 45 for TKIP, */
|
|
/* IEEE 802.11i-2004, 8.3.3.2, pag. 57 for CCMP */
|
|
if (DOT11DECRYPT_EXTIV(data[mac_header_len + 3]) == 0) {
|
|
DEBUG_PRINT_LINE("WEP encryption", DEBUG_LEVEL_3);
|
|
return Dot11DecryptWepMng(ctx, decrypt_data, mac_header_len, decrypt_len, key, &id);
|
|
} else {
|
|
DEBUG_PRINT_LINE("TKIP or CCMP encryption", DEBUG_LEVEL_3);
|
|
|
|
/* If the destination is a multicast address use the group key. This will not work if the AP is using
|
|
more than one group key simultaneously. I've not seen this in practice, however.
|
|
Usually an AP will rotate between the two key index values of 1 and 2 whenever
|
|
it needs to change the group key to be used. */
|
|
if (((const DOT11DECRYPT_MAC_FRAME_ADDR4 *)(data))->addr1[0] & 0x01) {
|
|
DEBUG_PRINT_LINE("Broadcast/Multicast address. This is encrypted with a group key.", DEBUG_LEVEL_3);
|
|
|
|
/* force STA address to broadcast MAC so we load the SA for the groupkey */
|
|
memcpy(id.sta, broadcast_mac, DOT11DECRYPT_MAC_LEN);
|
|
|
|
#ifdef DOT11DECRYPT_DEBUG
|
|
g_snprintf(msgbuf, MSGBUF_LEN, "ST_MAC: %2X.%2X.%2X.%2X.%2X.%2X\t", id.sta[0],id.sta[1],id.sta[2],id.sta[3],id.sta[4],id.sta[5]);
|
|
DEBUG_PRINT_LINE(msgbuf, DEBUG_LEVEL_3);
|
|
#endif
|
|
}
|
|
/* search for a cached Security Association for current BSSID and STA/broadcast MAC */
|
|
int ret = DOT11DECRYPT_RET_REQ_DATA;
|
|
sa = Dot11DecryptGetSa(ctx, &id);
|
|
if (sa != NULL) {
|
|
/* Decrypt the packet using the appropriate SA */
|
|
ret = Dot11DecryptRsnaMng(decrypt_data, mac_header_len, decrypt_len, key, sa);
|
|
}
|
|
if (ret != DOT11DECRYPT_RET_SUCCESS && Dot11DecryptGetNbrOfTkKeys(ctx) > 0) {
|
|
/* Decryption with known SAs failed. Try decrypt with TK user entries */
|
|
ret = Dot11DecryptUsingUserTk(ctx, decrypt_data, mac_header_len, decrypt_len, &id, key);
|
|
}
|
|
return ret;
|
|
}
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
INT Dot11DecryptSetKeys(
|
|
PDOT11DECRYPT_CONTEXT ctx,
|
|
DOT11DECRYPT_KEY_ITEM keys[],
|
|
const size_t keys_nr)
|
|
{
|
|
INT i;
|
|
INT success;
|
|
|
|
if (ctx==NULL || keys==NULL) {
|
|
DEBUG_PRINT_LINE("NULL context or NULL keys array", DEBUG_LEVEL_3);
|
|
return 0;
|
|
}
|
|
|
|
if (keys_nr>DOT11DECRYPT_MAX_KEYS_NR) {
|
|
DEBUG_PRINT_LINE("Keys number greater than maximum", DEBUG_LEVEL_3);
|
|
return 0;
|
|
}
|
|
|
|
/* clean key and SA collections before setting new ones */
|
|
Dot11DecryptInitContext(ctx);
|
|
|
|
/* check and insert keys */
|
|
for (i=0, success=0; i<(INT)keys_nr; i++) {
|
|
if (Dot11DecryptValidateKey(keys+i)==TRUE) {
|
|
if (keys[i].KeyType==DOT11DECRYPT_KEY_TYPE_WPA_PWD) {
|
|
DEBUG_PRINT_LINE("Set a WPA-PWD key", DEBUG_LEVEL_4);
|
|
Dot11DecryptRsnaPwd2Psk(keys[i].UserPwd.Passphrase, keys[i].UserPwd.Ssid, keys[i].UserPwd.SsidLen, keys[i].KeyData.Wpa.Psk);
|
|
keys[i].KeyData.Wpa.PskLen = DOT11DECRYPT_WPA_PWD_PSK_LEN;
|
|
}
|
|
#ifdef DOT11DECRYPT_DEBUG
|
|
else if (keys[i].KeyType==DOT11DECRYPT_KEY_TYPE_WPA_PMK) {
|
|
DEBUG_PRINT_LINE("Set a WPA-PMK key", DEBUG_LEVEL_4);
|
|
} else if (keys[i].KeyType==DOT11DECRYPT_KEY_TYPE_WEP) {
|
|
DEBUG_PRINT_LINE("Set a WEP key", DEBUG_LEVEL_4);
|
|
} else {
|
|
DEBUG_PRINT_LINE("Set a key", DEBUG_LEVEL_4);
|
|
}
|
|
#endif
|
|
memcpy(&ctx->keys[success], &keys[i], sizeof(keys[i]));
|
|
success++;
|
|
}
|
|
}
|
|
|
|
ctx->keys_nr=success;
|
|
return success;
|
|
}
|
|
|
|
static void
|
|
Dot11DecryptCleanKeys(
|
|
PDOT11DECRYPT_CONTEXT ctx)
|
|
{
|
|
if (ctx==NULL) {
|
|
DEBUG_PRINT_LINE("NULL context", DEBUG_LEVEL_5);
|
|
return;
|
|
}
|
|
|
|
memset(ctx->keys, 0, sizeof(DOT11DECRYPT_KEY_ITEM) * DOT11DECRYPT_MAX_KEYS_NR);
|
|
|
|
ctx->keys_nr=0;
|
|
|
|
DEBUG_PRINT_LINE("Keys collection cleaned!", DEBUG_LEVEL_5);
|
|
}
|
|
|
|
static void
|
|
Dot11DecryptRecurseCleanSA(
|
|
gpointer first_sa)
|
|
{
|
|
DOT11DECRYPT_SEC_ASSOCIATION *sa = (DOT11DECRYPT_SEC_ASSOCIATION *)first_sa;
|
|
if (sa != NULL) {
|
|
Dot11DecryptRecurseCleanSA((gpointer)sa->next);
|
|
g_free(sa);
|
|
}
|
|
}
|
|
|
|
static void
|
|
Dot11DecryptCleanSecAssoc(
|
|
PDOT11DECRYPT_CONTEXT ctx)
|
|
{
|
|
if (ctx->sa_hash != NULL) {
|
|
g_hash_table_destroy(ctx->sa_hash);
|
|
ctx->sa_hash = NULL;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* XXX - This won't be reliable if a packet containing SSID "B" shows
|
|
* up in the middle of a 4-way handshake for SSID "A".
|
|
* We should probably use a small array or hash table to keep multiple
|
|
* SSIDs.
|
|
*/
|
|
INT Dot11DecryptSetLastSSID(
|
|
PDOT11DECRYPT_CONTEXT ctx,
|
|
CHAR *pkt_ssid,
|
|
size_t pkt_ssid_len)
|
|
{
|
|
if (!ctx || !pkt_ssid || pkt_ssid_len < 1 || pkt_ssid_len > WPA_SSID_MAX_SIZE)
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
|
|
memcpy(ctx->pkt_ssid, pkt_ssid, pkt_ssid_len);
|
|
ctx->pkt_ssid_len = pkt_ssid_len;
|
|
|
|
return DOT11DECRYPT_RET_SUCCESS;
|
|
}
|
|
|
|
static guint
|
|
Dot11DecryptSaHash(gconstpointer key)
|
|
{
|
|
GBytes *bytes = g_bytes_new_static(key, sizeof(DOT11DECRYPT_SEC_ASSOCIATION_ID));
|
|
guint hash = g_bytes_hash(bytes);
|
|
g_bytes_unref(bytes);
|
|
return hash;
|
|
}
|
|
|
|
static gboolean
|
|
Dot11DecryptIsSaIdEqual(gconstpointer key1, gconstpointer key2)
|
|
{
|
|
return memcmp(key1, key2, sizeof(DOT11DECRYPT_SEC_ASSOCIATION_ID)) == 0;
|
|
}
|
|
|
|
INT Dot11DecryptInitContext(
|
|
PDOT11DECRYPT_CONTEXT ctx)
|
|
{
|
|
if (ctx==NULL) {
|
|
DEBUG_PRINT_LINE("NULL context", DEBUG_LEVEL_5);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
Dot11DecryptCleanKeys(ctx);
|
|
Dot11DecryptCleanSecAssoc(ctx);
|
|
|
|
ctx->pkt_ssid_len = 0;
|
|
ctx->sa_hash = g_hash_table_new_full(Dot11DecryptSaHash, Dot11DecryptIsSaIdEqual,
|
|
g_free, Dot11DecryptRecurseCleanSA);
|
|
if (ctx->sa_hash == NULL) {
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
DEBUG_PRINT_LINE("Context initialized!", DEBUG_LEVEL_5);
|
|
return DOT11DECRYPT_RET_SUCCESS;
|
|
}
|
|
|
|
INT Dot11DecryptDestroyContext(
|
|
PDOT11DECRYPT_CONTEXT ctx)
|
|
{
|
|
if (ctx==NULL) {
|
|
DEBUG_PRINT_LINE("NULL context", DEBUG_LEVEL_5);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
Dot11DecryptCleanKeys(ctx);
|
|
Dot11DecryptCleanSecAssoc(ctx);
|
|
|
|
DEBUG_PRINT_LINE("Context destroyed!", DEBUG_LEVEL_5);
|
|
return DOT11DECRYPT_RET_SUCCESS;
|
|
}
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
/****************************************************************************/
|
|
|
|
/****************************************************************************/
|
|
/* Internal function definitions */
|
|
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
static INT
|
|
Dot11DecryptRsnaMng(
|
|
UCHAR *decrypt_data,
|
|
guint mac_header_len,
|
|
guint *decrypt_len,
|
|
PDOT11DECRYPT_KEY_ITEM key,
|
|
DOT11DECRYPT_SEC_ASSOCIATION *sa)
|
|
{
|
|
INT ret = 1;
|
|
UCHAR *try_data;
|
|
guint try_data_len = *decrypt_len;
|
|
|
|
if (*decrypt_len == 0) {
|
|
DEBUG_PRINT_LINE("Invalid decryption length", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
/* allocate a temp buffer for the decryption loop */
|
|
try_data=(UCHAR *)g_malloc(try_data_len);
|
|
|
|
/* start of loop added by GCS */
|
|
for(/* sa */; sa != NULL ;sa=sa->next) {
|
|
|
|
if (sa->validKey==FALSE) {
|
|
DEBUG_PRINT_LINE("Key not yet valid", DEBUG_LEVEL_3);
|
|
continue;
|
|
}
|
|
|
|
/* copy the encrypted data into a temp buffer */
|
|
memcpy(try_data, decrypt_data, *decrypt_len);
|
|
|
|
if (sa->wpa.key_ver==1) {
|
|
/* CCMP -> HMAC-MD5 is the EAPOL-Key MIC, RC4 is the EAPOL-Key encryption algorithm */
|
|
DEBUG_PRINT_LINE("TKIP", DEBUG_LEVEL_3);
|
|
DEBUG_DUMP("ptk", sa->wpa.ptk, 64);
|
|
DEBUG_DUMP("ptk portion used", DOT11DECRYPT_GET_TK_TKIP(sa->wpa.ptk), 16);
|
|
|
|
if (*decrypt_len < (guint)mac_header_len) {
|
|
DEBUG_PRINT_LINE("Invalid decryption length", DEBUG_LEVEL_3);
|
|
g_free(try_data);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
if (*decrypt_len < DOT11DECRYPT_TKIP_MICLEN + DOT11DECRYPT_WEP_ICV) {
|
|
DEBUG_PRINT_LINE("Invalid decryption length", DEBUG_LEVEL_3);
|
|
g_free(try_data);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
ret = Dot11DecryptTkipDecrypt(try_data + mac_header_len, *decrypt_len - mac_header_len,
|
|
try_data + DOT11DECRYPT_TA_OFFSET,
|
|
DOT11DECRYPT_GET_TK_TKIP(sa->wpa.ptk));
|
|
if (ret) {
|
|
DEBUG_PRINT_LINE("TKIP failed!", DEBUG_LEVEL_3);
|
|
continue;
|
|
}
|
|
|
|
DEBUG_PRINT_LINE("TKIP DECRYPTED!!!", DEBUG_LEVEL_3);
|
|
/* remove MIC and ICV from the end of packet */
|
|
*decrypt_len -= DOT11DECRYPT_TKIP_MICLEN + DOT11DECRYPT_WEP_ICV;
|
|
break;
|
|
} else if (sa->wpa.cipher == 8 || sa->wpa.cipher == 9) {
|
|
DEBUG_PRINT_LINE("GCMP", DEBUG_LEVEL_3);
|
|
|
|
if (*decrypt_len < DOT11DECRYPT_GCMP_TRAILER) {
|
|
DEBUG_PRINT_LINE("Invalid decryption length", DEBUG_LEVEL_3);
|
|
g_free(try_data);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
ret = Dot11DecryptGcmpDecrypt(try_data, mac_header_len, (INT)*decrypt_len,
|
|
DOT11DECRYPT_GET_TK(sa->wpa.ptk, sa->wpa.akm),
|
|
Dot11DecryptGetTkLen(sa->wpa.cipher) / 8);
|
|
if (ret) {
|
|
continue;
|
|
}
|
|
DEBUG_PRINT_LINE("GCMP DECRYPTED!!!", DEBUG_LEVEL_3);
|
|
/* remove MIC from the end of packet */
|
|
*decrypt_len -= DOT11DECRYPT_GCMP_TRAILER;
|
|
break;
|
|
} else {
|
|
/* AES-CCMP -> HMAC-SHA1-128 is the EAPOL-Key MIC, AES wep_key wrap is the EAPOL-Key encryption algorithm */
|
|
DEBUG_PRINT_LINE("CCMP", DEBUG_LEVEL_3);
|
|
|
|
guint trailer = sa->wpa.cipher != 10 ? DOT11DECRYPT_CCMP_TRAILER : DOT11DECRYPT_CCMP_256_TRAILER;
|
|
if (*decrypt_len < trailer) {
|
|
DEBUG_PRINT_LINE("Invalid decryption length", DEBUG_LEVEL_3);
|
|
g_free(try_data);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
ret = Dot11DecryptCcmpDecrypt(try_data, mac_header_len, (INT)*decrypt_len,
|
|
DOT11DECRYPT_GET_TK(sa->wpa.ptk, sa->wpa.akm),
|
|
Dot11DecryptGetTkLen(sa->wpa.cipher) / 8,
|
|
trailer);
|
|
if (ret) {
|
|
continue;
|
|
}
|
|
DEBUG_PRINT_LINE("CCMP DECRYPTED!!!", DEBUG_LEVEL_3);
|
|
/* remove MIC from the end of packet */
|
|
*decrypt_len -= trailer;
|
|
break;
|
|
}
|
|
}
|
|
/* end of loop */
|
|
|
|
/* none of the keys worked */
|
|
if(sa == NULL) {
|
|
g_free(try_data);
|
|
return ret;
|
|
}
|
|
|
|
if (*decrypt_len > try_data_len || *decrypt_len < 8) {
|
|
DEBUG_PRINT_LINE("Invalid decryption length", DEBUG_LEVEL_3);
|
|
g_free(try_data);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
/* remove protection bit */
|
|
decrypt_data[1]&=0xBF;
|
|
|
|
/* remove TKIP/CCMP header */
|
|
*decrypt_len-=8;
|
|
|
|
if (*decrypt_len < mac_header_len) {
|
|
DEBUG_PRINT_LINE("Invalid decryption length < mac_header_len", DEBUG_LEVEL_3);
|
|
g_free(try_data);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
/* copy the decrypted data into the decrypt buffer GCS*/
|
|
memcpy(decrypt_data + mac_header_len, try_data + mac_header_len + 8,
|
|
*decrypt_len - mac_header_len);
|
|
g_free(try_data);
|
|
|
|
Dot11DecryptCopyKey(sa, key);
|
|
return DOT11DECRYPT_RET_SUCCESS;
|
|
}
|
|
|
|
static INT
|
|
Dot11DecryptWepMng(
|
|
PDOT11DECRYPT_CONTEXT ctx,
|
|
UCHAR *decrypt_data,
|
|
guint mac_header_len,
|
|
guint *decrypt_len,
|
|
PDOT11DECRYPT_KEY_ITEM key,
|
|
DOT11DECRYPT_SEC_ASSOCIATION_ID *id)
|
|
{
|
|
UCHAR wep_key[DOT11DECRYPT_WEP_KEY_MAXLEN+DOT11DECRYPT_WEP_IVLEN];
|
|
size_t keylen;
|
|
INT ret_value=1;
|
|
INT key_index;
|
|
DOT11DECRYPT_KEY_ITEM *tmp_key;
|
|
UINT8 useCache=FALSE;
|
|
UCHAR *try_data;
|
|
DOT11DECRYPT_SEC_ASSOCIATION *sa;
|
|
guint try_data_len = *decrypt_len;
|
|
|
|
try_data = (UCHAR *)g_malloc(try_data_len);
|
|
|
|
/* get the Security Association structure for the STA and AP */
|
|
|
|
/* For WEP the sa is used only for caching. When no sa exists all user
|
|
* entered WEP keys are checked and on successful packet decryption an
|
|
* sa is formed caching the key used for decryption.
|
|
*/
|
|
sa = Dot11DecryptGetSa(ctx, id);
|
|
if (sa != NULL && sa->key != NULL) {
|
|
useCache = TRUE;
|
|
}
|
|
|
|
for (key_index=0; key_index<(INT)ctx->keys_nr; key_index++) {
|
|
/* use the cached one, or try all keys */
|
|
if (!useCache) {
|
|
tmp_key=&ctx->keys[key_index];
|
|
} else {
|
|
if (sa->key!=NULL && sa->key->KeyType==DOT11DECRYPT_KEY_TYPE_WEP) {
|
|
DEBUG_PRINT_LINE("Try cached WEP key...", DEBUG_LEVEL_3);
|
|
tmp_key=sa->key;
|
|
} else {
|
|
DEBUG_PRINT_LINE("Cached key is not valid, try another WEP key...", DEBUG_LEVEL_3);
|
|
tmp_key=&ctx->keys[key_index];
|
|
}
|
|
}
|
|
|
|
/* obviously, try only WEP keys... */
|
|
if (tmp_key->KeyType==DOT11DECRYPT_KEY_TYPE_WEP) {
|
|
DEBUG_PRINT_LINE("Try WEP key...", DEBUG_LEVEL_3);
|
|
|
|
memset(wep_key, 0, sizeof(wep_key));
|
|
memcpy(try_data, decrypt_data, *decrypt_len);
|
|
|
|
/* Costruct the WEP seed: copy the IV in first 3 bytes and then the WEP key (refer to 802-11i-2004, 8.2.1.4.3, pag. 36) */
|
|
memcpy(wep_key, try_data+mac_header_len, DOT11DECRYPT_WEP_IVLEN);
|
|
keylen=tmp_key->KeyData.Wep.WepKeyLen;
|
|
memcpy(wep_key+DOT11DECRYPT_WEP_IVLEN, tmp_key->KeyData.Wep.WepKey, keylen);
|
|
|
|
ret_value=Dot11DecryptWepDecrypt(wep_key,
|
|
keylen+DOT11DECRYPT_WEP_IVLEN,
|
|
try_data + (mac_header_len+DOT11DECRYPT_WEP_IVLEN+DOT11DECRYPT_WEP_KIDLEN),
|
|
*decrypt_len-(mac_header_len+DOT11DECRYPT_WEP_IVLEN+DOT11DECRYPT_WEP_KIDLEN+DOT11DECRYPT_CRC_LEN));
|
|
|
|
if (ret_value == DOT11DECRYPT_RET_SUCCESS)
|
|
memcpy(decrypt_data, try_data, *decrypt_len);
|
|
}
|
|
|
|
if (!ret_value && tmp_key->KeyType==DOT11DECRYPT_KEY_TYPE_WEP) {
|
|
/* the tried key is the correct one, cache it in the Security Association */
|
|
|
|
/* Form an SA if one does not exist already */
|
|
if (sa == NULL) {
|
|
sa = Dot11DecryptNewSa(id);
|
|
if (sa == NULL) {
|
|
DEBUG_PRINT_LINE("Failed to alloc sa for WEP", DEBUG_LEVEL_3);
|
|
ret_value = DOT11DECRYPT_RET_UNSUCCESS;
|
|
break;
|
|
}
|
|
sa = Dot11DecryptAddSa(ctx, id, sa);
|
|
}
|
|
sa->key=tmp_key;
|
|
|
|
if (key!=NULL) {
|
|
memcpy(key, sa->key, sizeof(DOT11DECRYPT_KEY_ITEM));
|
|
key->KeyType=DOT11DECRYPT_KEY_TYPE_WEP;
|
|
}
|
|
|
|
break;
|
|
} else {
|
|
/* the cached key was not valid, try other keys */
|
|
|
|
if (useCache==TRUE) {
|
|
useCache=FALSE;
|
|
key_index--;
|
|
}
|
|
}
|
|
}
|
|
|
|
g_free(try_data);
|
|
if (ret_value)
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
|
|
DEBUG_PRINT_LINE("WEP DECRYPTED!!!", DEBUG_LEVEL_3);
|
|
|
|
/* remove ICV (4bytes) from the end of packet */
|
|
*decrypt_len-=4;
|
|
|
|
if (*decrypt_len < 4) {
|
|
DEBUG_PRINT_LINE("Decryption length too short", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
/* remove protection bit */
|
|
decrypt_data[1]&=0xBF;
|
|
|
|
/* remove IC header */
|
|
*decrypt_len-=4;
|
|
memmove(decrypt_data + mac_header_len,
|
|
decrypt_data + mac_header_len + DOT11DECRYPT_WEP_IVLEN + DOT11DECRYPT_WEP_KIDLEN,
|
|
*decrypt_len - mac_header_len);
|
|
|
|
return DOT11DECRYPT_RET_SUCCESS;
|
|
}
|
|
|
|
/* Refer to IEEE 802.11i-2004, 8.5.3, pag. 85 */
|
|
static INT
|
|
Dot11DecryptRsna4WHandshake(
|
|
PDOT11DECRYPT_CONTEXT ctx,
|
|
PDOT11DECRYPT_EAPOL_PARSED eapol_parsed,
|
|
const guint8 *eapol_raw,
|
|
DOT11DECRYPT_SEC_ASSOCIATION_ID *id,
|
|
const guint tot_len)
|
|
{
|
|
DOT11DECRYPT_KEY_ITEM *tmp_key, *tmp_pkt_key, pkt_key;
|
|
DOT11DECRYPT_SEC_ASSOCIATION *sa;
|
|
INT key_index;
|
|
INT ret = 1;
|
|
UCHAR useCache=FALSE;
|
|
UCHAR eapol[DOT11DECRYPT_EAPOL_MAX_LEN];
|
|
|
|
if (eapol_parsed->len > DOT11DECRYPT_EAPOL_MAX_LEN ||
|
|
eapol_parsed->key_len > DOT11DECRYPT_EAPOL_MAX_LEN ||
|
|
eapol_parsed->key_data_len > DOT11DECRYPT_EAPOL_MAX_LEN) {
|
|
DEBUG_PRINT_LINE("Too large EAPOL frame and/or key data", DEBUG_LEVEL_5);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
|
|
/* TODO timeouts? */
|
|
|
|
/* TODO consider key-index */
|
|
|
|
/* TODO considera Deauthentications */
|
|
|
|
DEBUG_PRINT_LINE("4-way handshake...", DEBUG_LEVEL_5);
|
|
|
|
/* manage 4-way handshake packets; this step completes the 802.1X authentication process (IEEE 802.11i-2004, pag. 85) */
|
|
|
|
/* message 1: Authenticator->Supplicant (Sec=0, Mic=0, Ack=1, Inst=0, Key=1(pairwise), KeyRSC=0, Nonce=ANonce, MIC=0) */
|
|
if (eapol_parsed->msg_type == DOT11DECRYPT_HS_MSG_TYPE_4WHS_1) {
|
|
DEBUG_PRINT_LINE("4-way handshake message 1", DEBUG_LEVEL_3);
|
|
|
|
/* On reception of Message 1, the Supplicant determines whether the Key Replay Counter field value has been */
|
|
/* used before with the current PMKSA. If the Key Replay Counter field value is less than or equal to the current */
|
|
/* local value, the Supplicant discards the message. */
|
|
/* -> not checked, the Authenticator will be send another Message 1 (hopefully!) */
|
|
|
|
/* save ANonce (from authenticator) to derive the PTK with the SNonce (from the 2 message) */
|
|
if (!eapol_parsed->nonce) {
|
|
DEBUG_PRINT_LINE("ANonce missing", DEBUG_LEVEL_5);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
|
|
sa = Dot11DecryptGetSa(ctx, id);
|
|
if (sa == NULL || sa->handshake >= 2) {
|
|
/* Either no SA exists or one exists but we're reauthenticating */
|
|
sa = Dot11DecryptNewSa(id);
|
|
if (sa == NULL) {
|
|
DEBUG_PRINT_LINE("Failed to alloc broadcast sa", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
sa = Dot11DecryptAddSa(ctx, id, sa);
|
|
}
|
|
memcpy(sa->wpa.nonce, eapol_parsed->nonce, 32);
|
|
|
|
/* get the Key Descriptor Version (to select algorithm used in decryption -CCMP or TKIP-) */
|
|
sa->wpa.key_ver = eapol_parsed->key_version;
|
|
sa->handshake=1;
|
|
return DOT11DECRYPT_RET_SUCCESS_HANDSHAKE;
|
|
}
|
|
|
|
/* message 2|4: Supplicant->Authenticator (Sec=0|1, Mic=1, Ack=0, Inst=0, Key=1(pairwise), KeyRSC=0, Nonce=SNonce|0, MIC=MIC(KCK,EAPOL)) */
|
|
if (eapol_parsed->msg_type == DOT11DECRYPT_HS_MSG_TYPE_4WHS_2) {
|
|
DEBUG_PRINT_LINE("4-way handshake message 2", DEBUG_LEVEL_3);
|
|
|
|
/* On reception of Message 2, the Authenticator checks that the key replay counter corresponds to the */
|
|
/* outstanding Message 1. If not, it silently discards the message. */
|
|
/* If the calculated MIC does not match the MIC that the Supplicant included in the EAPOL-Key frame, */
|
|
/* the Authenticator silently discards Message 2. */
|
|
/* -> not checked; the Supplicant will send another message 2 (hopefully!) */
|
|
|
|
sa = Dot11DecryptGetSa(ctx, id);
|
|
if (sa == NULL) {
|
|
DEBUG_PRINT_LINE("No SA for BSSID found", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
if (!eapol_parsed->nonce) {
|
|
DEBUG_PRINT_LINE("SNonce missing", DEBUG_LEVEL_5);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
if (sa->key != NULL) {
|
|
useCache = TRUE;
|
|
}
|
|
|
|
int akm = -1;
|
|
int cipher = -1;
|
|
int group_cipher = -1;
|
|
|
|
/* now you can derive the PTK */
|
|
for (key_index=0; key_index<(INT)ctx->keys_nr || useCache; key_index++) {
|
|
/* use the cached one, or try all keys */
|
|
if (!useCache) {
|
|
DEBUG_PRINT_LINE("Try WPA key...", DEBUG_LEVEL_3);
|
|
tmp_key=&ctx->keys[key_index];
|
|
} else {
|
|
/* there is a cached key in the security association, if it's a WPA key try it... */
|
|
if (sa->key!=NULL &&
|
|
(sa->key->KeyType==DOT11DECRYPT_KEY_TYPE_WPA_PWD ||
|
|
sa->key->KeyType==DOT11DECRYPT_KEY_TYPE_WPA_PSK ||
|
|
sa->key->KeyType==DOT11DECRYPT_KEY_TYPE_WPA_PMK)) {
|
|
DEBUG_PRINT_LINE("Try cached WPA key...", DEBUG_LEVEL_3);
|
|
tmp_key=sa->key;
|
|
} else {
|
|
DEBUG_PRINT_LINE("Cached key is of a wrong type, try WPA key...", DEBUG_LEVEL_3);
|
|
tmp_key=&ctx->keys[key_index];
|
|
}
|
|
}
|
|
|
|
/* obviously, try only WPA keys... */
|
|
if (tmp_key->KeyType==DOT11DECRYPT_KEY_TYPE_WPA_PWD ||
|
|
tmp_key->KeyType==DOT11DECRYPT_KEY_TYPE_WPA_PSK ||
|
|
tmp_key->KeyType==DOT11DECRYPT_KEY_TYPE_WPA_PMK)
|
|
{
|
|
if (tmp_key->KeyType == DOT11DECRYPT_KEY_TYPE_WPA_PWD && tmp_key->UserPwd.SsidLen == 0 && ctx->pkt_ssid_len > 0 && ctx->pkt_ssid_len <= DOT11DECRYPT_WPA_SSID_MAX_LEN) {
|
|
/* We have a "wildcard" SSID. Use the one from the packet. */
|
|
memcpy(&pkt_key, tmp_key, sizeof(pkt_key));
|
|
memcpy(&pkt_key.UserPwd.Ssid, ctx->pkt_ssid, ctx->pkt_ssid_len);
|
|
pkt_key.UserPwd.SsidLen = ctx->pkt_ssid_len;
|
|
Dot11DecryptRsnaPwd2Psk(pkt_key.UserPwd.Passphrase, pkt_key.UserPwd.Ssid,
|
|
pkt_key.UserPwd.SsidLen, pkt_key.KeyData.Wpa.Psk);
|
|
tmp_pkt_key = &pkt_key;
|
|
} else {
|
|
tmp_pkt_key = tmp_key;
|
|
}
|
|
memcpy(eapol, eapol_raw, tot_len);
|
|
|
|
/* From IEEE 802.11-2016 12.7.2 EAPOL-Key frames */
|
|
if (eapol_parsed->key_version == 0 || eapol_parsed->key_version == 3 ||
|
|
eapol_parsed->key_version == DOT11DECRYPT_WPA_KEY_VER_AES_CCMP)
|
|
{
|
|
/* PTK derivation is based on Authentication Key Management Type */
|
|
akm = eapol_parsed->akm;
|
|
cipher = eapol_parsed->cipher;
|
|
group_cipher = eapol_parsed->group_cipher;
|
|
} else if (eapol_parsed->key_version == DOT11DECRYPT_WPA_KEY_VER_NOT_CCMP) {
|
|
/* TKIP */
|
|
akm = 2;
|
|
cipher = 2;
|
|
group_cipher = 2;
|
|
} else {
|
|
DEBUG_PRINT_LINE("EAPOL key_version not supported", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
|
|
/* derive the PTK from the BSSID, STA MAC, PMK, SNonce, ANonce */
|
|
Dot11DecryptDerivePtk(sa, /* authenticator nonce, bssid, station mac */
|
|
tmp_pkt_key->KeyData.Wpa.Psk, /* PSK == PMK */
|
|
eapol_parsed->nonce, /* supplicant nonce */
|
|
eapol_parsed->key_version,
|
|
akm,
|
|
cipher);
|
|
DEBUG_DUMP("TK", DOT11DECRYPT_GET_TK(sa->wpa.ptk, akm), Dot11DecryptGetTkLen(cipher) / 8);
|
|
|
|
ret = Dot11DecryptRsnaMicCheck(eapol_parsed,
|
|
eapol, /* eapol frame (header also) */
|
|
tot_len, /* eapol frame length */
|
|
DOT11DECRYPT_GET_KCK(sa->wpa.ptk, akm),
|
|
eapol_parsed->key_version,
|
|
akm);
|
|
/* If the MIC is valid, the Authenticator checks that the RSN information element bit-wise matches */
|
|
/* that from the (Re)Association Request message. */
|
|
/* i) TODO If these are not exactly the same, the Authenticator uses MLME-DEAUTHENTICATE.request */
|
|
/* primitive to terminate the association. */
|
|
/* ii) If they do match bit-wise, the Authenticator constructs Message 3. */
|
|
}
|
|
|
|
if (!ret &&
|
|
(tmp_key->KeyType==DOT11DECRYPT_KEY_TYPE_WPA_PWD ||
|
|
tmp_key->KeyType==DOT11DECRYPT_KEY_TYPE_WPA_PSK ||
|
|
tmp_key->KeyType==DOT11DECRYPT_KEY_TYPE_WPA_PMK))
|
|
{
|
|
/* the temporary key is the correct one, cached in the Security Association */
|
|
|
|
sa->key=tmp_key;
|
|
break;
|
|
} else {
|
|
/* the cached key was not valid, try other keys */
|
|
|
|
if (useCache==TRUE) {
|
|
useCache=FALSE;
|
|
key_index--;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (ret) {
|
|
DEBUG_PRINT_LINE("handshake step failed", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
sa->wpa.key_ver = eapol_parsed->key_version;
|
|
sa->wpa.akm = akm;
|
|
sa->wpa.cipher = cipher;
|
|
sa->wpa.tmp_group_cipher = group_cipher;
|
|
sa->wpa.ptk_len = Dot11DecryptGetPtkLen(sa->wpa.akm, sa->wpa.cipher) / 8;
|
|
sa->handshake = 2;
|
|
sa->validKey = TRUE; /* we can use the key to decode, even if we have not captured the other eapol packets */
|
|
|
|
return DOT11DECRYPT_RET_SUCCESS_HANDSHAKE;
|
|
}
|
|
|
|
/* message 3: Authenticator->Supplicant (Sec=1, Mic=1, Ack=1, Inst=0/1, Key=1(pairwise), KeyRSC=???, Nonce=ANonce, MIC=1) */
|
|
if (eapol_parsed->msg_type == DOT11DECRYPT_HS_MSG_TYPE_4WHS_3) {
|
|
DEBUG_PRINT_LINE("4-way handshake message 3", DEBUG_LEVEL_3);
|
|
|
|
/* On reception of Message 3, the Supplicant silently discards the message if the Key Replay Counter field */
|
|
/* value has already been used or if the ANonce value in Message 3 differs from the ANonce value in Message 1. */
|
|
/* -> not checked, the Authenticator will send another message 3 (hopefully!) */
|
|
|
|
/* TODO check page 88 (RNS) */
|
|
|
|
/* If using WPA2 PSK, message 3 will contain an RSN for the group key (GTK KDE).
|
|
In order to properly support decrypting WPA2-PSK packets, we need to parse this to get the group key. */
|
|
if (eapol_parsed->key_type == DOT11DECRYPT_RSN_WPA2_KEY_DESCRIPTOR) {
|
|
return Dot11DecryptCopyBroadcastKey(ctx, eapol_parsed, id);
|
|
}
|
|
}
|
|
|
|
/* message 4 */
|
|
if (eapol_parsed->msg_type == DOT11DECRYPT_HS_MSG_TYPE_4WHS_4) {
|
|
/* TODO "Note that when the 4-Way Handshake is first used Message 4 is sent in the clear." */
|
|
|
|
/* TODO check MIC and Replay Counter */
|
|
/* On reception of Message 4, the Authenticator verifies that the Key Replay Counter field value is one */
|
|
/* that it used on this 4-Way Handshake; if it is not, it silently discards the message. */
|
|
/* If the calculated MIC does not match the MIC that the Supplicant included in the EAPOL-Key frame, the */
|
|
/* Authenticator silently discards Message 4. */
|
|
|
|
DEBUG_PRINT_LINE("4-way handshake message 4", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_SUCCESS_HANDSHAKE;
|
|
}
|
|
return DOT11DECRYPT_RET_NO_VALID_HANDSHAKE;
|
|
}
|
|
|
|
/* From IEEE 802.11-2016 Table 12-8 Integrity and key-wrap algorithms */
|
|
static int
|
|
Dot11DecryptGetIntegrityAlgoFromAkm(int akm, int *algo, gboolean *hmac)
|
|
{
|
|
int res = 0;
|
|
switch (akm) {
|
|
case 1:
|
|
case 2:
|
|
*algo = GCRY_MD_SHA1;
|
|
*hmac = TRUE;
|
|
break;
|
|
#if GCRYPT_VERSION_NUMBER >= 0x010600
|
|
case 3:
|
|
case 4:
|
|
case 5:
|
|
case 6:
|
|
case 7:
|
|
case 8:
|
|
case 9:
|
|
case 10:
|
|
*algo = GCRY_MAC_CMAC_AES;
|
|
*hmac = FALSE;
|
|
break;
|
|
#endif
|
|
case 11:
|
|
case 18:
|
|
*algo = GCRY_MD_SHA256;
|
|
*hmac = TRUE;
|
|
break;
|
|
case 12:
|
|
case 13:
|
|
*algo = GCRY_MD_SHA384;
|
|
*hmac = TRUE;
|
|
break;
|
|
default:
|
|
/* Unknown / Not supported yet */
|
|
res = -1;
|
|
break;
|
|
}
|
|
return res;
|
|
}
|
|
|
|
static INT
|
|
Dot11DecryptRsnaMicCheck(
|
|
PDOT11DECRYPT_EAPOL_PARSED eapol_parsed,
|
|
UCHAR *eapol,
|
|
USHORT eapol_len,
|
|
UCHAR *KCK,
|
|
USHORT key_ver,
|
|
int akm)
|
|
{
|
|
guint8 *mic = eapol_parsed->mic;
|
|
guint16 mic_len = eapol_parsed->mic_len;
|
|
guint16 kck_len = Dot11DecryptGetKckLen(akm) / 8;
|
|
/* MIC 16 or 24 bytes, though HMAC-SHA256 / SHA384 algos need 32 / 48 bytes buffer */
|
|
UCHAR c_mic[48] = { 0 };
|
|
int algo = -1;
|
|
gboolean hmac = TRUE;
|
|
|
|
if (!mic || mic_len > DOT11DECRYPT_WPA_MICKEY_MAX_LEN) {
|
|
DEBUG_PRINT_LINE("Not a valid mic", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
/* set to 0 the MIC in the EAPOL packet (to calculate the MIC) */
|
|
memset(eapol + DOT11DECRYPT_WPA_MICKEY_OFFSET + 4, 0, mic_len);
|
|
|
|
if (key_ver==DOT11DECRYPT_WPA_KEY_VER_NOT_CCMP) {
|
|
/* use HMAC-MD5 for the EAPOL-Key MIC */
|
|
algo = GCRY_MD_MD5;
|
|
hmac = TRUE;
|
|
} else if (key_ver==DOT11DECRYPT_WPA_KEY_VER_AES_CCMP) {
|
|
/* use HMAC-SHA1-128 for the EAPOL-Key MIC */
|
|
algo = GCRY_MD_SHA1;
|
|
hmac = TRUE;
|
|
} else {
|
|
/* Mic check algoritm determined by AKM type */
|
|
if (Dot11DecryptGetIntegrityAlgoFromAkm(akm, &algo, &hmac)) {
|
|
DEBUG_PRINT_LINE("Unknown Mic check algo", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
};
|
|
}
|
|
if (hmac) {
|
|
if (ws_hmac_buffer(algo, c_mic, eapol, eapol_len, KCK, kck_len)) {
|
|
DEBUG_PRINT_LINE("HMAC_BUFFER", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
} else {
|
|
if (ws_cmac_buffer(algo, c_mic, eapol, eapol_len, KCK, kck_len)) {
|
|
DEBUG_PRINT_LINE("HMAC_BUFFER", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
}
|
|
|
|
/* compare calculated MIC with the Key MIC and return result (0 means success) */
|
|
DEBUG_DUMP("mic", mic, mic_len);
|
|
DEBUG_DUMP("c_mic", c_mic, mic_len);
|
|
return memcmp(mic, c_mic, mic_len);
|
|
}
|
|
|
|
static INT
|
|
Dot11DecryptValidateKey(
|
|
PDOT11DECRYPT_KEY_ITEM key)
|
|
{
|
|
size_t len;
|
|
UCHAR ret=TRUE;
|
|
|
|
if (key==NULL) {
|
|
DEBUG_PRINT_LINE("NULL key", DEBUG_LEVEL_5);
|
|
return FALSE;
|
|
}
|
|
|
|
switch (key->KeyType) {
|
|
case DOT11DECRYPT_KEY_TYPE_WEP:
|
|
/* check key size limits */
|
|
len=key->KeyData.Wep.WepKeyLen;
|
|
if (len<DOT11DECRYPT_WEP_KEY_MINLEN || len>DOT11DECRYPT_WEP_KEY_MAXLEN) {
|
|
DEBUG_PRINT_LINE("WEP key: key length not accepted", DEBUG_LEVEL_5);
|
|
ret=FALSE;
|
|
}
|
|
break;
|
|
|
|
case DOT11DECRYPT_KEY_TYPE_WEP_40:
|
|
/* set the standard length and use a generic WEP key type */
|
|
key->KeyData.Wep.WepKeyLen=DOT11DECRYPT_WEP_40_KEY_LEN;
|
|
key->KeyType=DOT11DECRYPT_KEY_TYPE_WEP;
|
|
break;
|
|
|
|
case DOT11DECRYPT_KEY_TYPE_WEP_104:
|
|
/* set the standard length and use a generic WEP key type */
|
|
key->KeyData.Wep.WepKeyLen=DOT11DECRYPT_WEP_104_KEY_LEN;
|
|
key->KeyType=DOT11DECRYPT_KEY_TYPE_WEP;
|
|
break;
|
|
|
|
case DOT11DECRYPT_KEY_TYPE_WPA_PWD:
|
|
/* check passphrase and SSID size limits */
|
|
len=strlen(key->UserPwd.Passphrase);
|
|
if (len<DOT11DECRYPT_WPA_PASSPHRASE_MIN_LEN || len>DOT11DECRYPT_WPA_PASSPHRASE_MAX_LEN) {
|
|
DEBUG_PRINT_LINE("WPA-PWD key: passphrase length not accepted", DEBUG_LEVEL_5);
|
|
ret=FALSE;
|
|
}
|
|
|
|
len=key->UserPwd.SsidLen;
|
|
if (len>DOT11DECRYPT_WPA_SSID_MAX_LEN) {
|
|
DEBUG_PRINT_LINE("WPA-PWD key: ssid length not accepted", DEBUG_LEVEL_5);
|
|
ret=FALSE;
|
|
}
|
|
|
|
break;
|
|
|
|
case DOT11DECRYPT_KEY_TYPE_WPA_PSK:
|
|
break;
|
|
|
|
case DOT11DECRYPT_KEY_TYPE_TK:
|
|
break;
|
|
|
|
default:
|
|
ret=FALSE;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static INT
|
|
Dot11DecryptGetSaAddress(
|
|
const DOT11DECRYPT_MAC_FRAME_ADDR4 *frame,
|
|
DOT11DECRYPT_SEC_ASSOCIATION_ID *id)
|
|
{
|
|
#ifdef DOT11DECRYPT_DEBUG
|
|
#define MSGBUF_LEN 255
|
|
CHAR msgbuf[MSGBUF_LEN];
|
|
#endif
|
|
|
|
if ((DOT11DECRYPT_TYPE(frame->fc[0])==DOT11DECRYPT_TYPE_DATA) &&
|
|
(DOT11DECRYPT_DS_BITS(frame->fc[1]) == 0) &&
|
|
(memcmp(frame->addr2, frame->addr3, DOT11DECRYPT_MAC_LEN) != 0) &&
|
|
(memcmp(frame->addr1, frame->addr3, DOT11DECRYPT_MAC_LEN) != 0)) {
|
|
/* DATA frame with fromDS=0 ToDS=0 and neither RA or SA is BSSID
|
|
=> TDLS traffic. Use highest MAC address for bssid */
|
|
if (memcmp(frame->addr1, frame->addr2, DOT11DECRYPT_MAC_LEN) < 0) {
|
|
memcpy(id->sta, frame->addr1, DOT11DECRYPT_MAC_LEN);
|
|
memcpy(id->bssid, frame->addr2, DOT11DECRYPT_MAC_LEN);
|
|
} else {
|
|
memcpy(id->sta, frame->addr2, DOT11DECRYPT_MAC_LEN);
|
|
memcpy(id->bssid, frame->addr1, DOT11DECRYPT_MAC_LEN);
|
|
}
|
|
} else {
|
|
const UCHAR *addr;
|
|
|
|
/* Normal Case: SA between STA and AP */
|
|
if ((addr = Dot11DecryptGetBssidAddress(frame)) != NULL) {
|
|
memcpy(id->bssid, addr, DOT11DECRYPT_MAC_LEN);
|
|
} else {
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
if ((addr = Dot11DecryptGetStaAddress(frame)) != NULL) {
|
|
memcpy(id->sta, addr, DOT11DECRYPT_MAC_LEN);
|
|
} else {
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
}
|
|
|
|
#ifdef DOT11DECRYPT_DEBUG
|
|
g_snprintf(msgbuf, MSGBUF_LEN, "BSSID_MAC: %02X.%02X.%02X.%02X.%02X.%02X\t",
|
|
id->bssid[0],id->bssid[1],id->bssid[2],id->bssid[3],id->bssid[4],id->bssid[5]);
|
|
DEBUG_PRINT_LINE(msgbuf, DEBUG_LEVEL_3);
|
|
g_snprintf(msgbuf, MSGBUF_LEN, "STA_MAC: %02X.%02X.%02X.%02X.%02X.%02X\t",
|
|
id->sta[0],id->sta[1],id->sta[2],id->sta[3],id->sta[4],id->sta[5]);
|
|
DEBUG_PRINT_LINE(msgbuf, DEBUG_LEVEL_3);
|
|
#endif
|
|
|
|
return DOT11DECRYPT_RET_SUCCESS;
|
|
}
|
|
|
|
/*
|
|
* Dot11DecryptGetBssidAddress() and Dot11DecryptGetBssidAddress() are used for
|
|
* key caching. In each case, it's more important to return a value than
|
|
* to return a _correct_ value, so we fudge addresses in some cases, e.g.
|
|
* the BSSID in bridged connections.
|
|
* FromDS ToDS Sta BSSID
|
|
* 0 0 addr1/2 addr3
|
|
* 0 1 addr2 addr1
|
|
* 1 0 addr1 addr2
|
|
* 1 1 addr2 addr1
|
|
*/
|
|
|
|
static const UCHAR *
|
|
Dot11DecryptGetStaAddress(
|
|
const DOT11DECRYPT_MAC_FRAME_ADDR4 *frame)
|
|
{
|
|
switch(DOT11DECRYPT_DS_BITS(frame->fc[1])) { /* Bit 1 = FromDS, bit 0 = ToDS */
|
|
case 0:
|
|
if (memcmp(frame->addr2, frame->addr3, DOT11DECRYPT_MAC_LEN) == 0)
|
|
return frame->addr1;
|
|
else
|
|
return frame->addr2;
|
|
case 1:
|
|
return frame->addr2;
|
|
case 2:
|
|
return frame->addr1;
|
|
case 3:
|
|
if (memcmp(frame->addr1, frame->addr2, DOT11DECRYPT_MAC_LEN) < 0)
|
|
return frame->addr1;
|
|
else
|
|
return frame->addr2;
|
|
|
|
default:
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
static const UCHAR *
|
|
Dot11DecryptGetBssidAddress(
|
|
const DOT11DECRYPT_MAC_FRAME_ADDR4 *frame)
|
|
{
|
|
switch(DOT11DECRYPT_DS_BITS(frame->fc[1])) { /* Bit 1 = FromDS, bit 0 = ToDS */
|
|
case 0:
|
|
return frame->addr3;
|
|
case 1:
|
|
return frame->addr1;
|
|
case 2:
|
|
return frame->addr2;
|
|
case 3:
|
|
if (memcmp(frame->addr1, frame->addr2, DOT11DECRYPT_MAC_LEN) > 0)
|
|
return frame->addr1;
|
|
else
|
|
return frame->addr2;
|
|
|
|
default:
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
/* From IEEE 802.11-2016 Table 9-131 Cipher suite selectors and
|
|
* Table 12-4 Cipher suite key lengths */
|
|
static int Dot11DecryptGetTkLen(int cipher)
|
|
{
|
|
switch (cipher) {
|
|
case 1: return 40; /* WEP-40 */
|
|
case 2: return 256; /* TKIP */
|
|
case 3: return -1; /* Reserved */
|
|
case 4: return 128; /* CCMP-128 */
|
|
case 5: return 104; /* WEP-104 */
|
|
case 6: return 128; /* BIP-CMAC-128 */
|
|
case 7: return -1; /* Group addressed traffic not allowed */
|
|
case 8: return 128; /* GCMP-128 */
|
|
case 9: return 256; /* GCMP-256 */
|
|
case 10: return 256; /* CCMP-256 */
|
|
case 11: return 128; /* BIP-GMAC-128 */
|
|
case 12: return 256; /* BIP-GMAC-256 */
|
|
case 13: return 256; /* BIP-CMAC-256 */
|
|
default:
|
|
DEBUG_PRINT_LINE("Unknown cipher", DEBUG_LEVEL_3);
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
/* From IEEE 802.11-2016 Table 12-8 Integrity and key-wrap algorithms */
|
|
static int Dot11DecryptGetKckLen(int akm)
|
|
{
|
|
switch (akm) {
|
|
case 1: return 128;
|
|
case 2: return 128;
|
|
case 3: return 128;
|
|
case 4: return 128;
|
|
case 5: return 128;
|
|
case 6: return 128;
|
|
case 8: return 128;
|
|
case 9: return 128;
|
|
case 11: return 128;
|
|
case 12: return 192;
|
|
case 13: return 192;
|
|
case 18: return 128;
|
|
default:
|
|
/* Unknown / Not supported */
|
|
DEBUG_PRINT_LINE("Unknown akm", DEBUG_LEVEL_3);
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
/* From IEEE 802.11-2016 Table 12-8 Integrity and key-wrap algorithms */
|
|
static int Dot11DecryptGetKekLen(int akm)
|
|
{
|
|
switch (akm) {
|
|
case 1: return 128;
|
|
case 2: return 128;
|
|
case 3: return 128;
|
|
case 4: return 128;
|
|
case 5: return 128;
|
|
case 6: return 128;
|
|
case 8: return 128;
|
|
case 9: return 128;
|
|
case 11: return 128;
|
|
case 12: return 256;
|
|
case 13: return 256;
|
|
case 18: return 128;
|
|
default:
|
|
/* Unknown / Not supported */
|
|
DEBUG_PRINT_LINE("Unknown akm", DEBUG_LEVEL_3);
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
/* From IEEE 802.11-2016 9.4.2.25.3 AKM suites and
|
|
* Table 12-8 Integrity and key-wrap algorithms */
|
|
static int Dot11DecryptGetPtkLen(int akm, int cipher)
|
|
{
|
|
int kck_len = Dot11DecryptGetKckLen(akm);
|
|
int kek_len = Dot11DecryptGetKekLen(akm);
|
|
int tk_len = Dot11DecryptGetTkLen(cipher);
|
|
|
|
if (kck_len == -1 || kek_len == -1 || tk_len == -1) {
|
|
DEBUG_PRINT_LINE("Invalid PTK len", DEBUG_LEVEL_3);
|
|
return -1;
|
|
}
|
|
return kck_len + kek_len + tk_len;
|
|
}
|
|
|
|
/* From IEEE 802.11-2016 12.7.1.2 PRF and Table 9-133 AKM suite selectors */
|
|
static DOT11DECRYPT_PTK_DERIVE_FUNC
|
|
Dot11DecryptGetDeriveFuncFromAkm(int akm)
|
|
{
|
|
DOT11DECRYPT_PTK_DERIVE_FUNC func = NULL;
|
|
switch (akm) {
|
|
case 1:
|
|
case 2:
|
|
func = Dot11DecryptRsnaPrfX;
|
|
break;
|
|
case 3:
|
|
case 4:
|
|
case 5:
|
|
case 6:
|
|
case 7:
|
|
case 8:
|
|
case 9:
|
|
case 10:
|
|
case 11:
|
|
case 12:
|
|
case 13:
|
|
case 18:
|
|
func = Dot11DecryptRsnaKdfX;
|
|
break;
|
|
default:
|
|
/* Unknown / Not supported yet */
|
|
break;
|
|
}
|
|
return func;
|
|
}
|
|
|
|
/* From IEEE 802.11-2016 12.7.1.2 PRF and Table 9-133 AKM suite selectors */
|
|
static int
|
|
Dot11DecryptGetDeriveAlgoFromAkm(int akm)
|
|
{
|
|
int algo = -1;
|
|
switch (akm) {
|
|
case 1:
|
|
case 2:
|
|
algo = GCRY_MD_SHA1;
|
|
break;
|
|
case 3:
|
|
case 4:
|
|
case 5:
|
|
case 6:
|
|
case 7:
|
|
case 8:
|
|
case 9:
|
|
case 10:
|
|
case 11:
|
|
case 18:
|
|
algo = GCRY_MD_SHA256;
|
|
break;
|
|
case 12:
|
|
case 13:
|
|
algo = GCRY_MD_SHA384;
|
|
break;
|
|
default:
|
|
/* Unknown / Not supported yet */
|
|
break;
|
|
}
|
|
return algo;
|
|
}
|
|
|
|
/* derive the PTK from the BSSID, STA MAC, PMK, SNonce, ANonce */
|
|
static void
|
|
Dot11DecryptDerivePtk(
|
|
DOT11DECRYPT_SEC_ASSOCIATION *sa,
|
|
const UCHAR *pmk,
|
|
const UCHAR snonce[32],
|
|
int key_version,
|
|
int akm,
|
|
int cipher)
|
|
{
|
|
#ifdef DOT11DECRYPT_DEBUG
|
|
#define MSGBUF_LEN 255
|
|
CHAR msgbuf[MSGBUF_LEN];
|
|
#endif
|
|
int algo = -1;
|
|
int ptk_len_bits = -1;
|
|
DOT11DECRYPT_PTK_DERIVE_FUNC DerivePtk = NULL;
|
|
if (key_version == DOT11DECRYPT_WPA_KEY_VER_NOT_CCMP) {
|
|
/* TKIP */
|
|
ptk_len_bits = 512;
|
|
DerivePtk = Dot11DecryptRsnaPrfX;
|
|
algo = GCRY_MD_SHA1;
|
|
} else {
|
|
/* From IEEE 802.11-2016 Table 12-8 Integrity and key-wrap algorithms */
|
|
ptk_len_bits = Dot11DecryptGetPtkLen(akm, cipher);
|
|
DerivePtk = Dot11DecryptGetDeriveFuncFromAkm(akm);
|
|
algo = Dot11DecryptGetDeriveAlgoFromAkm(akm);
|
|
|
|
#ifdef DOT11DECRYPT_DEBUG
|
|
g_snprintf(msgbuf, MSGBUF_LEN, "ptk_len_bits: %d, algo: %d, cipher: %d", ptk_len_bits, algo, cipher);
|
|
DEBUG_PRINT_LINE(msgbuf, DEBUG_LEVEL_3);
|
|
#endif /* DOT11DECRYPT_DEBUG */
|
|
}
|
|
|
|
if (ptk_len_bits == -1 || !DerivePtk || algo == -1) {
|
|
return;
|
|
}
|
|
DerivePtk(sa, pmk, snonce, ptk_len_bits, sa->wpa.ptk, algo);
|
|
}
|
|
|
|
/* Function used to derive the PTK. Refer to IEEE 802.11I-2004, pag. 74
|
|
* and IEEE 802.11i-2004, pag. 164 */
|
|
static void
|
|
Dot11DecryptRsnaPrfX(
|
|
DOT11DECRYPT_SEC_ASSOCIATION *sa,
|
|
const UCHAR *pmk,
|
|
const UCHAR snonce[32],
|
|
const INT x, /* for TKIP 512, for CCMP 384 */
|
|
UCHAR *ptk,
|
|
int hash_algo)
|
|
{
|
|
UINT8 i;
|
|
UCHAR R[100];
|
|
INT offset=sizeof("Pairwise key expansion");
|
|
UCHAR output[80]; /* allow for sha1 overflow. */
|
|
int hash_len = 20;
|
|
|
|
memset(R, 0, 100);
|
|
|
|
memcpy(R, "Pairwise key expansion", offset);
|
|
|
|
/* Min(AA, SPA) || Max(AA, SPA) */
|
|
if (memcmp(sa->saId.sta, sa->saId.bssid, DOT11DECRYPT_MAC_LEN) < 0)
|
|
{
|
|
memcpy(R + offset, sa->saId.sta, DOT11DECRYPT_MAC_LEN);
|
|
memcpy(R + offset+DOT11DECRYPT_MAC_LEN, sa->saId.bssid, DOT11DECRYPT_MAC_LEN);
|
|
}
|
|
else
|
|
{
|
|
memcpy(R + offset, sa->saId.bssid, DOT11DECRYPT_MAC_LEN);
|
|
memcpy(R + offset+DOT11DECRYPT_MAC_LEN, sa->saId.sta, DOT11DECRYPT_MAC_LEN);
|
|
}
|
|
|
|
offset+=DOT11DECRYPT_MAC_LEN*2;
|
|
|
|
/* Min(ANonce,SNonce) || Max(ANonce,SNonce) */
|
|
if( memcmp(snonce, sa->wpa.nonce, 32) < 0 )
|
|
{
|
|
memcpy(R + offset, snonce, 32);
|
|
memcpy(R + offset + 32, sa->wpa.nonce, 32);
|
|
}
|
|
else
|
|
{
|
|
memcpy(R + offset, sa->wpa.nonce, 32);
|
|
memcpy(R + offset + 32, snonce, 32);
|
|
}
|
|
|
|
offset+=32*2;
|
|
|
|
for(i = 0; i < (x+159)/160; i++)
|
|
{
|
|
R[offset] = i;
|
|
if (ws_hmac_buffer(hash_algo, &output[hash_len * i], R, 100, pmk, 32)) {
|
|
return;
|
|
}
|
|
}
|
|
memcpy(ptk, output, x/8);
|
|
}
|
|
|
|
/* From IEEE 802.11-2016 12.7.1.7.2 Key derivation function (KDF) */
|
|
static void
|
|
Dot11DecryptRsnaKdfX(
|
|
DOT11DECRYPT_SEC_ASSOCIATION *sa,
|
|
const UCHAR *pmk,
|
|
const UCHAR snonce[32],
|
|
const INT x,
|
|
UCHAR *ptk,
|
|
int hash_algo)
|
|
{
|
|
static const char *const label = "Pairwise key expansion";
|
|
/* LABEL_LEN = strlen("Pairwise key expansion") */
|
|
#define LABEL_LEN (22)
|
|
/* R_LEN = "i || Label || Context || Length" */
|
|
#define R_LEN (2 + LABEL_LEN + DOT11DECRYPT_MAC_LEN * 2 + 2 * 32 + 2)
|
|
|
|
UCHAR R[R_LEN];
|
|
guint16 i;
|
|
INT offset = 0;
|
|
UCHAR output[48 * 2]; /* Big enough for largest algo results (SHA-384) */
|
|
guint16 hash_len = (hash_algo == GCRY_MD_SHA384) ? 48 : 32;
|
|
memset(R, 0, R_LEN);
|
|
|
|
offset += 2; /* i */
|
|
memcpy(R + offset, label, LABEL_LEN);
|
|
offset += LABEL_LEN;
|
|
|
|
/* Min(AA, SPA) || Max(AA, SPA) */
|
|
if (memcmp(sa->saId.sta, sa->saId.bssid, DOT11DECRYPT_MAC_LEN) < 0)
|
|
{
|
|
memcpy(R + offset, sa->saId.sta, DOT11DECRYPT_MAC_LEN);
|
|
memcpy(R + offset+DOT11DECRYPT_MAC_LEN, sa->saId.bssid, DOT11DECRYPT_MAC_LEN);
|
|
}
|
|
else
|
|
{
|
|
memcpy(R + offset, sa->saId.bssid, DOT11DECRYPT_MAC_LEN);
|
|
memcpy(R + offset+DOT11DECRYPT_MAC_LEN, sa->saId.sta, DOT11DECRYPT_MAC_LEN);
|
|
}
|
|
offset += DOT11DECRYPT_MAC_LEN * 2;
|
|
|
|
/* Min(ANonce,SNonce) || Max(ANonce,SNonce) */
|
|
if( memcmp(snonce, sa->wpa.nonce, 32) < 0 )
|
|
{
|
|
memcpy(R + offset, snonce, 32);
|
|
memcpy(R + offset + 32, sa->wpa.nonce, 32);
|
|
}
|
|
else
|
|
{
|
|
memcpy(R + offset, sa->wpa.nonce, 32);
|
|
memcpy(R + offset + 32, snonce, 32);
|
|
}
|
|
offset += 32 * 2;
|
|
|
|
guint16 len_le = GUINT16_TO_LE(x);
|
|
memcpy(R + offset, &len_le, 2);
|
|
offset += 2;
|
|
|
|
for (i = 0; i < (x + 255) / (hash_len * 8) ; i++)
|
|
{
|
|
guint16 count_le = GUINT16_TO_LE(i + 1);
|
|
memcpy(R, &count_le, 2);
|
|
|
|
if (ws_hmac_buffer(hash_algo, &output[hash_len * i], R, offset, pmk, hash_len)) {
|
|
return;
|
|
}
|
|
}
|
|
memcpy(ptk, output, x / 8);
|
|
}
|
|
|
|
#define MAX_SSID_LENGTH 32 /* maximum SSID length */
|
|
|
|
static INT
|
|
Dot11DecryptRsnaPwd2PskStep(
|
|
const guint8 *ppBytes,
|
|
const guint ppLength,
|
|
const CHAR *ssid,
|
|
const size_t ssidLength,
|
|
const INT iterations,
|
|
const INT count,
|
|
UCHAR *output)
|
|
{
|
|
UCHAR digest[MAX_SSID_LENGTH+4] = { 0 }; /* SSID plus 4 bytes of count */
|
|
INT i, j;
|
|
|
|
if (ssidLength > MAX_SSID_LENGTH) {
|
|
/* This "should not happen" */
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
/* U1 = PRF(P, S || INT(i)) */
|
|
memcpy(digest, ssid, ssidLength);
|
|
digest[ssidLength] = (UCHAR)((count>>24) & 0xff);
|
|
digest[ssidLength+1] = (UCHAR)((count>>16) & 0xff);
|
|
digest[ssidLength+2] = (UCHAR)((count>>8) & 0xff);
|
|
digest[ssidLength+3] = (UCHAR)(count & 0xff);
|
|
if (ws_hmac_buffer(GCRY_MD_SHA1, digest, digest, (guint32) ssidLength + 4, ppBytes, ppLength)) {
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
/* output = U1 */
|
|
memcpy(output, digest, 20);
|
|
for (i = 1; i < iterations; i++) {
|
|
/* Un = PRF(P, Un-1) */
|
|
if (ws_hmac_buffer(GCRY_MD_SHA1, digest, digest, HASH_SHA1_LENGTH, ppBytes, ppLength)) {
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
|
|
/* output = output xor Un */
|
|
for (j = 0; j < 20; j++) {
|
|
output[j] ^= digest[j];
|
|
}
|
|
}
|
|
|
|
return DOT11DECRYPT_RET_SUCCESS;
|
|
}
|
|
|
|
static INT
|
|
Dot11DecryptRsnaPwd2Psk(
|
|
const CHAR *passphrase,
|
|
const CHAR *ssid,
|
|
const size_t ssidLength,
|
|
UCHAR *output)
|
|
{
|
|
UCHAR m_output[40] = { 0 };
|
|
GByteArray *pp_ba = g_byte_array_new();
|
|
|
|
if (!uri_str_to_bytes(passphrase, pp_ba)) {
|
|
g_byte_array_free(pp_ba, TRUE);
|
|
return 0;
|
|
}
|
|
|
|
Dot11DecryptRsnaPwd2PskStep(pp_ba->data, pp_ba->len, ssid, ssidLength, 4096, 1, m_output);
|
|
Dot11DecryptRsnaPwd2PskStep(pp_ba->data, pp_ba->len, ssid, ssidLength, 4096, 2, &m_output[20]);
|
|
|
|
memcpy(output, m_output, DOT11DECRYPT_WPA_PWD_PSK_LEN);
|
|
g_byte_array_free(pp_ba, TRUE);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Returns the decryption_key_t struct given a string describing the key.
|
|
* Returns NULL if the input_string cannot be parsed.
|
|
*/
|
|
decryption_key_t*
|
|
parse_key_string(gchar* input_string, guint8 key_type)
|
|
{
|
|
gchar *key, *tmp_str;
|
|
gchar *ssid;
|
|
|
|
GString *key_string = NULL;
|
|
GByteArray *ssid_ba = NULL, *key_ba;
|
|
gboolean res;
|
|
|
|
gchar **tokens;
|
|
guint n = 0;
|
|
decryption_key_t *dk;
|
|
|
|
if(input_string == NULL)
|
|
return NULL;
|
|
|
|
/*
|
|
* Parse the input_string. WEP and WPA will be just a string
|
|
* of hexadecimal characters (if key is wrong, null will be
|
|
* returned...).
|
|
* WPA-PWD should be in the form
|
|
* <key data>[:<ssid>]
|
|
*/
|
|
|
|
switch(key_type)
|
|
{
|
|
case DOT11DECRYPT_KEY_TYPE_WEP:
|
|
case DOT11DECRYPT_KEY_TYPE_WEP_40:
|
|
case DOT11DECRYPT_KEY_TYPE_WEP_104:
|
|
|
|
key_ba = g_byte_array_new();
|
|
res = hex_str_to_bytes(input_string, key_ba, FALSE);
|
|
|
|
if (res && key_ba->len > 0) {
|
|
/* Key is correct! It was probably an 'old style' WEP key */
|
|
/* Create the decryption_key_t structure, fill it and return it*/
|
|
dk = g_new(decryption_key_t, 1);
|
|
|
|
dk->type = DOT11DECRYPT_KEY_TYPE_WEP;
|
|
/* XXX - The current key handling code in the GUI requires
|
|
* no separators and lower case */
|
|
tmp_str = bytes_to_str(NULL, key_ba->data, key_ba->len);
|
|
dk->key = g_string_new(tmp_str);
|
|
g_string_ascii_down(dk->key);
|
|
dk->bits = key_ba->len * 8;
|
|
dk->ssid = NULL;
|
|
|
|
wmem_free(NULL, tmp_str);
|
|
g_byte_array_free(key_ba, TRUE);
|
|
return dk;
|
|
}
|
|
|
|
/* Key doesn't work */
|
|
g_byte_array_free(key_ba, TRUE);
|
|
return NULL;
|
|
|
|
case DOT11DECRYPT_KEY_TYPE_WPA_PWD:
|
|
|
|
tokens = g_strsplit(input_string,":",0);
|
|
|
|
/* Tokens is a null termiated array of strings ... */
|
|
while(tokens[n] != NULL)
|
|
n++;
|
|
|
|
if(n < 1)
|
|
{
|
|
/* Free the array of strings */
|
|
g_strfreev(tokens);
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* The first token is the key
|
|
*/
|
|
key = g_strdup(tokens[0]);
|
|
|
|
ssid = NULL;
|
|
/* Maybe there is a second token (an ssid, if everything else is ok) */
|
|
if(n >= 2)
|
|
{
|
|
ssid = g_strdup(tokens[1]);
|
|
}
|
|
|
|
/* Create a new string */
|
|
key_string = g_string_new(key);
|
|
ssid_ba = NULL;
|
|
|
|
/* Two (or more) tokens mean that the user entered a WPA-PWD key ... */
|
|
if( ((key_string->len) > WPA_KEY_MAX_CHAR_SIZE) || ((key_string->len) < WPA_KEY_MIN_CHAR_SIZE))
|
|
{
|
|
g_string_free(key_string, TRUE);
|
|
|
|
g_free(key);
|
|
g_free(ssid);
|
|
|
|
/* Free the array of strings */
|
|
g_strfreev(tokens);
|
|
return NULL;
|
|
}
|
|
|
|
if(ssid != NULL) /* more than two tokens found, means that the user specified the ssid */
|
|
{
|
|
ssid_ba = g_byte_array_new();
|
|
if (! uri_str_to_bytes(ssid, ssid_ba)) {
|
|
g_string_free(key_string, TRUE);
|
|
g_byte_array_free(ssid_ba, TRUE);
|
|
g_free(key);
|
|
g_free(ssid);
|
|
/* Free the array of strings */
|
|
g_strfreev(tokens);
|
|
return NULL;
|
|
}
|
|
|
|
if(ssid_ba->len > WPA_SSID_MAX_CHAR_SIZE)
|
|
{
|
|
g_string_free(key_string, TRUE);
|
|
g_byte_array_free(ssid_ba, TRUE);
|
|
|
|
g_free(key);
|
|
g_free(ssid);
|
|
|
|
/* Free the array of strings */
|
|
g_strfreev(tokens);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
/* Key was correct!!! Create the new decryption_key_t ... */
|
|
dk = g_new(decryption_key_t, 1);
|
|
|
|
dk->type = DOT11DECRYPT_KEY_TYPE_WPA_PWD;
|
|
dk->key = g_string_new(key);
|
|
dk->bits = 256; /* This is the length of the array pf bytes that will be generated using key+ssid ...*/
|
|
dk->ssid = byte_array_dup(ssid_ba); /* NULL if ssid_ba is NULL */
|
|
|
|
g_string_free(key_string, TRUE);
|
|
if (ssid_ba != NULL)
|
|
g_byte_array_free(ssid_ba, TRUE);
|
|
|
|
g_free(key);
|
|
g_free(ssid);
|
|
|
|
/* Free the array of strings */
|
|
g_strfreev(tokens);
|
|
return dk;
|
|
|
|
case DOT11DECRYPT_KEY_TYPE_WPA_PSK:
|
|
|
|
key_ba = g_byte_array_new();
|
|
res = hex_str_to_bytes(input_string, key_ba, FALSE);
|
|
|
|
/* Two tokens means that the user should have entered a WPA-BIN key ... */
|
|
if(!res || (key_ba->len != DOT11DECRYPT_WPA_PWD_PSK_LEN &&
|
|
key_ba->len != DOT11DECRYPT_WPA_PMK_MAX_LEN))
|
|
{
|
|
g_byte_array_free(key_ba, TRUE);
|
|
|
|
/* No ssid has been created ... */
|
|
return NULL;
|
|
}
|
|
|
|
/* Key was correct!!! Create the new decryption_key_t ... */
|
|
dk = g_new(decryption_key_t, 1);
|
|
|
|
dk->type = DOT11DECRYPT_KEY_TYPE_WPA_PSK;
|
|
dk->key = g_string_new(input_string);
|
|
dk->bits = (guint) dk->key->len * 4;
|
|
dk->ssid = NULL;
|
|
|
|
g_byte_array_free(key_ba, TRUE);
|
|
return dk;
|
|
|
|
case DOT11DECRYPT_KEY_TYPE_TK:
|
|
{
|
|
/* From IEEE 802.11-2016 Table 12-4 Cipher suite key lengths */
|
|
static const guint8 allowed_key_lengths[] = {
|
|
// TBD 40 / 8, /* WEP-40 */
|
|
// TBD 104 / 8, /* WEP-104 */
|
|
256 / 8, /* TKIP, GCMP-256, CCMP-256 */
|
|
128 / 8, /* CCMP-128, GCMP-128 */
|
|
};
|
|
gboolean key_length_ok = FALSE;
|
|
|
|
key_ba = g_byte_array_new();
|
|
res = hex_str_to_bytes(input_string, key_ba, FALSE);
|
|
|
|
for (size_t i = 0; i < sizeof(allowed_key_lengths); i++) {
|
|
if (key_ba->len == allowed_key_lengths[i]) {
|
|
key_length_ok = TRUE;
|
|
break;
|
|
}
|
|
}
|
|
if (!res || !key_length_ok) {
|
|
g_byte_array_free(key_ba, TRUE);
|
|
return NULL;
|
|
}
|
|
dk = g_new(decryption_key_t, 1);
|
|
dk->type = DOT11DECRYPT_KEY_TYPE_TK;
|
|
dk->key = g_string_new(input_string);
|
|
dk->bits = (guint) dk->key->len * 4;
|
|
dk->ssid = NULL;
|
|
|
|
g_byte_array_free(key_ba, TRUE);
|
|
return dk;
|
|
}
|
|
}
|
|
|
|
/* Type not supported */
|
|
return NULL;
|
|
}
|
|
|
|
void
|
|
free_key_string(decryption_key_t *dk)
|
|
{
|
|
if (dk->key)
|
|
g_string_free(dk->key, TRUE);
|
|
if (dk->ssid)
|
|
g_byte_array_free(dk->ssid, TRUE);
|
|
g_free(dk);
|
|
}
|
|
|
|
static INT
|
|
Dot11DecryptTDLSDeriveKey(
|
|
PDOT11DECRYPT_SEC_ASSOCIATION sa,
|
|
const guint8 *data,
|
|
#if GCRYPT_VERSION_NUMBER >= 0x010600
|
|
guint offset_rsne,
|
|
#else
|
|
guint offset_rsne _U_,
|
|
#endif
|
|
guint offset_fte,
|
|
#if GCRYPT_VERSION_NUMBER >= 0x010600
|
|
guint offset_timeout,
|
|
#else
|
|
guint offset_timeout _U_,
|
|
#endif
|
|
guint offset_link,
|
|
#if GCRYPT_VERSION_NUMBER >= 0x010600
|
|
guint8 action)
|
|
#else
|
|
guint8 action _U_)
|
|
#endif
|
|
{
|
|
|
|
gcry_md_hd_t sha256_handle;
|
|
gcry_md_hd_t hmac_handle;
|
|
const guint8 *snonce, *anonce, *initiator, *responder, *bssid;
|
|
guint8 key_input[32];
|
|
#if GCRYPT_VERSION_NUMBER >= 0x010600
|
|
guint8 mic[16], seq_num = action + 1;
|
|
guint8 zeros[16] = { 0 };
|
|
gcry_mac_hd_t cmac_handle;
|
|
size_t cmac_len = 16;
|
|
size_t cmac_write_len;
|
|
#endif
|
|
|
|
/* Get key input */
|
|
anonce = &data[offset_fte + 20];
|
|
snonce = &data[offset_fte + 52];
|
|
|
|
gcry_md_open (&sha256_handle, GCRY_MD_SHA256, 0);
|
|
if (memcmp(anonce, snonce, DOT11DECRYPT_WPA_NONCE_LEN) < 0) {
|
|
gcry_md_write(sha256_handle, anonce, DOT11DECRYPT_WPA_NONCE_LEN);
|
|
gcry_md_write(sha256_handle, snonce, DOT11DECRYPT_WPA_NONCE_LEN);
|
|
} else {
|
|
gcry_md_write(sha256_handle, snonce, DOT11DECRYPT_WPA_NONCE_LEN);
|
|
gcry_md_write(sha256_handle, anonce, DOT11DECRYPT_WPA_NONCE_LEN);
|
|
}
|
|
memcpy(key_input, gcry_md_read(sha256_handle, 0), 32);
|
|
gcry_md_close(sha256_handle);
|
|
|
|
/* Derive key */
|
|
bssid = &data[offset_link + 2];
|
|
initiator = &data[offset_link + 8];
|
|
responder = &data[offset_link + 14];
|
|
if (gcry_md_open(&hmac_handle, GCRY_MD_SHA256, GCRY_MD_FLAG_HMAC)) {
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
if (gcry_md_setkey(hmac_handle, key_input, 32)) {
|
|
gcry_md_close(hmac_handle);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
gcry_md_putc(hmac_handle, 1);
|
|
gcry_md_putc(hmac_handle, 0);
|
|
gcry_md_write(hmac_handle, "TDLS PMK", 8);
|
|
if (memcmp(initiator, responder, DOT11DECRYPT_MAC_LEN) < 0) {
|
|
gcry_md_write(hmac_handle, initiator, DOT11DECRYPT_MAC_LEN);
|
|
gcry_md_write(hmac_handle, responder, DOT11DECRYPT_MAC_LEN);
|
|
} else {
|
|
gcry_md_write(hmac_handle, responder, DOT11DECRYPT_MAC_LEN);
|
|
gcry_md_write(hmac_handle, initiator, DOT11DECRYPT_MAC_LEN);
|
|
}
|
|
gcry_md_write(hmac_handle, bssid, DOT11DECRYPT_MAC_LEN);
|
|
gcry_md_putc(hmac_handle, 0);
|
|
gcry_md_putc(hmac_handle, 1);
|
|
memcpy(key_input, gcry_md_read(hmac_handle, 0), 32);
|
|
gcry_md_close(hmac_handle);
|
|
|
|
/* Check MIC */
|
|
#if GCRYPT_VERSION_NUMBER >= 0x010600
|
|
if (gcry_mac_open(&cmac_handle, GCRY_MAC_CMAC_AES, 0, NULL)) {
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
if (gcry_mac_setkey(cmac_handle, key_input, 16)) {
|
|
gcry_mac_close(cmac_handle);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
gcry_mac_write(cmac_handle, initiator, DOT11DECRYPT_MAC_LEN);
|
|
gcry_mac_write(cmac_handle, responder, DOT11DECRYPT_MAC_LEN);
|
|
gcry_mac_write(cmac_handle, &seq_num, 1);
|
|
gcry_mac_write(cmac_handle, &data[offset_link], data[offset_link + 1] + 2);
|
|
gcry_mac_write(cmac_handle, &data[offset_rsne], data[offset_rsne + 1] + 2);
|
|
gcry_mac_write(cmac_handle, &data[offset_timeout], data[offset_timeout + 1] + 2);
|
|
gcry_mac_write(cmac_handle, &data[offset_fte], 4);
|
|
gcry_mac_write(cmac_handle, zeros, 16);
|
|
cmac_write_len = data[offset_fte + 1] + 2;
|
|
if (cmac_write_len < 20) {
|
|
DEBUG_PRINT_LINE("Bad MAC len", DEBUG_LEVEL_3);
|
|
gcry_mac_close(cmac_handle);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
gcry_mac_write(cmac_handle, &data[offset_fte + 20], cmac_write_len - 20);
|
|
if (gcry_mac_read(cmac_handle, mic, &cmac_len) != GPG_ERR_NO_ERROR) {
|
|
DEBUG_PRINT_LINE("MAC read error", DEBUG_LEVEL_3);
|
|
gcry_mac_close(cmac_handle);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
if (memcmp(mic, &data[offset_fte + 4], 16)) {
|
|
DEBUG_PRINT_LINE("MIC verification failed", DEBUG_LEVEL_3);
|
|
gcry_mac_close(cmac_handle);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
}
|
|
gcry_mac_close(cmac_handle);
|
|
#else
|
|
DEBUG_PRINT_LINE("MIC verification failed, need libgcrypt >= 1.6", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_UNSUCCESS;
|
|
#endif
|
|
/* TODO support other akm and ciphers? */
|
|
sa->wpa.akm = 2;
|
|
sa->wpa.cipher = 4;
|
|
sa->wpa.ptk_len = Dot11DecryptGetPtkLen(sa->wpa.akm, sa->wpa.cipher) / 8;
|
|
memcpy(DOT11DECRYPT_GET_TK(sa->wpa.ptk, sa->wpa.akm),
|
|
key_input + 16, Dot11DecryptGetTkLen(sa->wpa.cipher) / 8);
|
|
memcpy(sa->wpa.nonce, snonce, DOT11DECRYPT_WPA_NONCE_LEN);
|
|
sa->validKey = TRUE;
|
|
sa->wpa.key_ver = DOT11DECRYPT_WPA_KEY_VER_AES_CCMP;
|
|
DEBUG_PRINT_LINE("MIC verified", DEBUG_LEVEL_3);
|
|
return DOT11DECRYPT_RET_SUCCESS;
|
|
}
|
|
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
/****************************************************************************/
|
|
|
|
/*
|
|
* Editor modelines
|
|
*
|
|
* Local Variables:
|
|
* c-basic-offset: 4
|
|
* tab-width: 8
|
|
* indent-tabs-mode: nil
|
|
* End:
|
|
*
|
|
* ex: set shiftwidth=4 tabstop=8 expandtab:
|
|
* :indentSize=4:tabSize=8:noTabs=true:
|
|
*/
|