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[wpa] Add general support for WPA-protected 802.11 networks

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Modified-by: Marty Connor <mdc@etherboot.org>
Signed-off-by: Marty Connor <mdc@etherboot.org>
This commit is contained in:
Joshua Oreman 2009-08-07 23:03:40 -07:00 committed by Marty Connor
parent 432cc6d1d8
commit 8ec18a5b50
3 changed files with 1477 additions and 0 deletions
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1
src/include/gpxe/errfile.h
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@ -161,6 +161,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
#define ERRFILE_sec80211 ( ERRFILE_NET | 0x00230000 )
#define ERRFILE_wep ( ERRFILE_NET | 0x00240000 )
#define ERRFILE_eapol ( ERRFILE_NET | 0x00250000 )
#define ERRFILE_wpa ( ERRFILE_NET | 0x00260000 )
#define ERRFILE_image ( ERRFILE_IMAGE | 0x00000000 )
#define ERRFILE_elf ( ERRFILE_IMAGE | 0x00010000 )

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src/include/gpxe/wpa.h Normal file
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/*
* Copyright (c) 2009 Joshua Oreman <oremanj@rwcr.net>.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef _GPXE_WPA_H
#define _GPXE_WPA_H
#include <gpxe/ieee80211.h>
#include <gpxe/list.h>
FILE_LICENCE ( GPL2_OR_LATER );
/** @file
*
* Common definitions for all types of WPA-protected networks.
*/
/** EAPOL-Key type field for modern 802.11i/RSN WPA packets */
#define EAPOL_KEY_TYPE_RSN 2
/** Old EAPOL-Key type field used by WPA1 hardware before 802.11i ratified */
#define EAPOL_KEY_TYPE_WPA 254
/**
* @defgroup eapol_key_info EAPOL-Key Info field bits
* @{
*/
/** Key descriptor version, indicating WPA or WPA2 */
#define EAPOL_KEY_INFO_VERSION 0x0007
/** Key type bit, indicating pairwise or group */
#define EAPOL_KEY_INFO_TYPE 0x0008
/** Key install bit; set on message 3 except when legacy hacks are used */
#define EAPOL_KEY_INFO_INSTALL 0x0040
/** Key ACK bit; set when a response is required, on all messages except #4 */
#define EAPOL_KEY_INFO_KEY_ACK 0x0080
/** Key MIC bit; set when the MIC field is valid, on messages 3 and 4 */
#define EAPOL_KEY_INFO_KEY_MIC 0x0100
/** Secure bit; set when both sides have both keys, on messages 3 and 4 */
#define EAPOL_KEY_INFO_SECURE 0x0200
/** Error bit; set on a MIC failure for TKIP */
#define EAPOL_KEY_INFO_ERROR 0x0400
/** Request bit; set when authentication is initiated by the Peer (unusual) */
#define EAPOL_KEY_INFO_REQUEST 0x0800
/** Key Encrypted bit; set when the Key Data field is encrypted */
#define EAPOL_KEY_INFO_KEY_ENC 0x1000
/** SMC Message bit; set when this frame is part of an IBSS SMK handshake */
#define EAPOL_KEY_INFO_SMC_MESS 0x2000
/** Key descriptor version field value for WPA (TKIP) */
#define EAPOL_KEY_VERSION_WPA 1
/** Key descriptor version field value for WPA2 (CCMP) */
#define EAPOL_KEY_VERSION_WPA2 2
/** Key type field value for a PTK (pairwise) key handshake */
#define EAPOL_KEY_TYPE_PTK 0x0008
/** Key type field value for a GTK (group) key handshake */
#define EAPOL_KEY_TYPE_GTK 0x0000
/** @} */
/** An EAPOL-Key packet.
*
* These are used for the WPA 4-Way Handshake, whether or not prior
* authentication has been performed using EAP.
*
* On LANs, an eapol_key_pkt is always encapsulated in the data field
* of an eapol_frame, with the frame's type code set to EAPOL_TYPE_KEY.
*
* Unlike 802.11 frame headers, the fields in this structure are
* stored in big-endian!
*/
struct eapol_key_pkt
{
/** One of the EAPOL_KEY_TYPE_* defines. */
u8 type;
/** Bitfield of key characteristics, network byte order */
u16 info;
/** Length of encryption key to be used, network byte order
*
* This is 16 for CCMP, 32 for TKIP, and 5 or 13 for WEP.
*/
u16 keysize;
/** Monotonically increasing value for EAPOL-Key conversations
*
* In another classic demonstration of overengineering, this
* 8-byte value will rarely be anything above 1. It's stored
* in network byte order.
*/
u64 replay;
/** Nonce value
*
* This is the authenticator's ANonce in frame 1, the peer's
* SNonce in frame 2, and 0 in frames 3 and 4.
*/
u8 nonce[32];
/** Initialization vector
*
* This contains the IV used with the Key Encryption Key, or 0
* if the key is unencrypted or encrypted using an algorithm
* that does not require an IV.
*/
u8 iv[16];
/** Receive sequence counter for GTK
*
* This is used to synchronize the client's replay counter for
* ordinary data packets. The first six bytes contain PN0
* through PN5 for CCMP mode, or TSC0 through TSC5 for TKIP
* mode. The last two bytes are zero.
*/
u8 rsc[8];
/** Reserved bytes */
u8 _reserved[8];
/** Message integrity code over the entire EAPOL frame
*
* This is calculated using HMAC-MD5 when the key descriptor
* version field in @a info is 1, and HMAC-SHA1 ignoring the
* last 4 bytes of the hash when the version field in @a info
* is 2.
*/
u8 mic[16];
/** Length of the @a data field in bytes, network byte order */
u16 datalen;
/** Key data
*
* This is formatted as a series of 802.11 information
* elements, with cryptographic data encapsulated using a
* "vendor-specific IE" code and an IEEE-specified OUI.
*/
u8 data[0];
} __attribute__ (( packed ));
/** WPA handshaking state */
enum wpa_state {
/** Waiting for PMK to be set */
WPA_WAITING = 0,
/** Ready for 4-Way Handshake */
WPA_READY,
/** Performing 4-Way Handshake */
WPA_WORKING,
/** 4-Way Handshake succeeded */
WPA_SUCCESS,
/** 4-Way Handshake failed */
WPA_FAILURE,
};
/** Bitfield indicating a selection of WPA transient keys */
enum wpa_keymask {
/** Pairwise transient key */
WPA_PTK = 1,
/** Group transient key */
WPA_GTK = 2,
};
/** Length of a nonce */
#define WPA_NONCE_LEN 32
/** Length of a TKIP main key */
#define WPA_TKIP_KEY_LEN 16
/** Length of a TKIP MIC key */
#define WPA_TKIP_MIC_KEY_LEN 8
/** Length of a CCMP key */
#define WPA_CCMP_KEY_LEN 16
/** Length of an EAPOL Key Confirmation Key */
#define WPA_KCK_LEN 16
/** Length of an EAPOL Key Encryption Key */
#define WPA_KEK_LEN 16
/** Usual length of a Pairwise Master Key */
#define WPA_PMK_LEN 32
/** Length of a PMKID */
#define WPA_PMKID_LEN 16
/** Structure of the Temporal Key for TKIP encryption */
struct tkip_tk
{
/** Main key: input to TKIP Phase 1 and Phase 2 key mixing functions */
u8 key[WPA_TKIP_KEY_LEN];
/** Michael MIC keys */
struct {
/** MIC key for packets from the AP */
u8 rx[WPA_TKIP_MIC_KEY_LEN];
/** MIC key for packets to the AP */
u8 tx[WPA_TKIP_MIC_KEY_LEN];
} __attribute__ (( packed )) mic;
} __attribute__ (( packed ));
/** Structure of a generic Temporal Key */
union wpa_tk
{
/** CCMP key */
u8 ccmp[WPA_CCMP_KEY_LEN];
/** TKIP keys */
struct tkip_tk tkip;
};
/** Structure of the Pairwise Transient Key */
struct wpa_ptk
{
/** EAPOL-Key Key Confirmation Key (KCK) */
u8 kck[WPA_KCK_LEN];
/** EAPOL-Key Key Encryption Key (KEK) */
u8 kek[WPA_KEK_LEN];
/** Temporal key */
union wpa_tk tk;
} __attribute__ (( packed ));
/** Structure of the Group Transient Key */
struct wpa_gtk
{
/** Temporal key */
union wpa_tk tk;
} __attribute__ (( packed ));
/** Common context for WPA security handshaking
*
* Any implementor of a particular handshaking type (e.g. PSK or EAP)
* must include this structure at the very beginning of their private
* data context structure, to allow the EAPOL-Key handling code to
* work. When the preliminary authentication is done, it is necessary
* to call wpa_start(), passing the PMK (derived from PSK or EAP MSK)
* as an argument. The handshaker can use its @a step function to
* monitor @a state in this wpa_ctx structure for success or
* failure. On success, the keys will be available in @a ptk and @a
* gtk according to the state of the @a valid bitmask.
*
* After an initial success, the parent handshaker does not need to
* concern itself with rekeying; the WPA common code takes care of
* that.
*/
struct wpa_common_ctx
{
/** 802.11 device we are authenticating for */
struct net80211_device *dev;
/** The Pairwise Master Key to use in handshaking
*
* This is set either by running the PBKDF2 algorithm on a
* passphrase with the SSID as salt to generate a pre-shared
* key, or by copying the first 32 bytes of the EAP Master
* Session Key in 802.1X-served authentication.
*/
u8 pmk[WPA_PMK_LEN];
/** Length of the Pairwise Master Key
*
* This is always 32 except with one EAP method which only
* gives 16 bytes.
*/
int pmk_len;
/** State of EAPOL-Key handshaking */
enum wpa_state state;
/** Replay counter for this association
*
* This stores the replay counter value for the most recent
* packet we've accepted. It is initially initialised to ~0 to
* show we'll accept anything.
*/
u64 replay;
/** Mask of valid keys after authentication success
*
* If the PTK is not valid, the GTK should be used for both
* unicast and multicast decryption; if the GTK is not valid,
* multicast packets cannot be decrypted.
*/
enum wpa_keymask valid;
/** The cipher to use for unicast RX and all TX */
enum net80211_crypto_alg crypt;
/** The cipher to use for broadcast and multicast RX */
enum net80211_crypto_alg gcrypt;
/** The Pairwise Transient Key derived from the handshake */
struct wpa_ptk ptk;
/** The Group Transient Key derived from the handshake */
struct wpa_gtk gtk;
/** Authenticator-provided nonce */
u8 Anonce[WPA_NONCE_LEN];
/** Supplicant-generated nonce (that's us) */
u8 Snonce[WPA_NONCE_LEN];
/** Whether we should refrain from generating another SNonce */
int have_Snonce;
/** Data in WPA or RSN IE from AP's beacon frame */
void *ap_rsn_ie;
/** Length of @a ap_rsn_ie */
int ap_rsn_ie_len;
/** Whether @a ap_rsn_ie is an RSN IE (as opposed to old WPA) */
int ap_rsn_is_rsn;
/** List entry */
struct list_head list;
};
/** WPA handshake key integrity and encryption handler
*
* Note that due to the structure of the 4-Way Handshake we never
* actually need to encrypt key data, only decrypt it.
*/
struct wpa_kie {
/** Value of version bits in EAPOL-Key info field for which to use
*
* This should be one of the @c EAPOL_KEY_VERSION_* constants.
*/
int version;
/** Calculate MIC over message
*
* @v kck Key Confirmation Key, 16 bytes
* @v msg Message to calculate MIC over
* @v len Number of bytes to calculate MIC over
* @ret mic Calculated MIC, 16 bytes long
*
* The @a mic return may point within @a msg, so it must not
* be filled until the calculation has been performed.
*/
void ( * mic ) ( const void *kck, const void *msg, size_t len,
void *mic );
/** Decrypt key data
*
* @v kek Key Encryption Key, 16 bytes
* @v iv Initialisation vector for encryption, 16 bytes
* @v msg Message to decrypt (Key Data field)
* @v len Length of message
* @ret msg Decrypted message in place of original
* @ret len Updated to reflect encrypted length
* @ret rc Return status code
*
* The decrypted message is written over the encrypted one.
*/
int ( * decrypt ) ( const void *kek, const void *iv, void *msg,
u16 *len );
};
#define WPA_KIES __table ( struct wpa_kie, "wpa_kies" )
#define __wpa_kie __table_entry ( WPA_KIES, 01 )
/**
* @defgroup wpa_kde Key descriptor element types
* @{
*/
/** Payload structure of the GTK-encapsulating KDE
*
* This does not include the IE type, length, or OUI bytes, which are
* generic to all KDEs.
*/
struct wpa_kde_gtk_encap
{
/** Key ID and TX bit */
u8 id;
/** Reserved byte */
u8 _rsvd;
/** Encapsulated group transient key */
struct wpa_gtk gtk;
} __attribute__ (( packed ));
/** Mask for Key ID in wpa_kde_gtk::id field */
#define WPA_GTK_KID 0x03
/** Mask for Tx bit in wpa_kde_gtk::id field */
#define WPA_GTK_TXBIT 0x04
/** KDE type for an encapsulated Group Transient Key (requires encryption) */
#define WPA_KDE_GTK _MKOUI ( 0x00, 0x0F, 0xAC, 0x01 )
/** KDE type for a MAC address */
#define WPA_KDE_MAC _MKOUI ( 0x00, 0x0F, 0xAC, 0x03 )
/** KDE type for a PMKID */
#define WPA_KDE_PMKID _MKOUI ( 0x00, 0x0F, 0xAC, 0x04 )
/** KDE type for a nonce */
#define WPA_KDE_NONCE _MKOUI ( 0x00, 0x0F, 0xAC, 0x06 )
/** KDE type for a lifetime value */
#define WPA_KDE_LIFETIME _MKOUI ( 0x00, 0x0F, 0xAC, 0x07 )
/** Any key descriptor element type
*
* KDEs follow the 802.11 information element format of a type byte
* (in this case "vendor-specific", with the requisite OUI+subtype
* after length) and a length byte whose value does not include the
* length of the type and length bytes.
*/
struct wpa_kde
{
/** Information element type: always 0xDD (IEEE80211_IE_VENDOR) */
u8 ie_type;
/** Length, not including ie_type and length fields */
u8 len;
/** OUI + type byte */
u32 oui_type;
/** Payload data */
union {
/** For GTK-type KDEs, encapsulated GTK */
struct wpa_kde_gtk_encap gtk_encap;
/** For MAC-type KDEs, the MAC address */
u8 mac[ETH_ALEN];
/** For PMKID-type KDEs, the PMKID */
u8 pmkid[WPA_PMKID_LEN];
/** For Nonce-type KDEs, the nonce */
u8 nonce[WPA_NONCE_LEN];
/** For Lifetime-type KDEs, the lifetime in seconds
*
* This is in network byte order!
*/
u32 lifetime;
};
} __attribute__ (( packed ));
/** @} */
int wpa_make_rsn_ie ( struct net80211_device *dev, union ieee80211_ie **ie );
int wpa_start ( struct net80211_device *dev, struct wpa_common_ctx *ctx,
const void *pmk, size_t pmk_len );
void wpa_stop ( struct net80211_device *dev );
#endif /* _GPXE_WPA_H */

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src/net/80211/wpa.c Normal file
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/*
* Copyright (c) 2009 Joshua Oreman <oremanj@rwcr.net>.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
FILE_LICENCE ( GPL2_OR_LATER );
#include <gpxe/net80211.h>
#include <gpxe/sec80211.h>
#include <gpxe/wpa.h>
#include <gpxe/eapol.h>
#include <gpxe/crypto.h>
#include <gpxe/arc4.h>
#include <gpxe/crc32.h>
#include <gpxe/sha1.h>
#include <gpxe/hmac.h>
#include <gpxe/list.h>
#include <gpxe/ethernet.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
/** @file
*
* Handler for the aspects of WPA handshaking that are independent of
* 802.1X/PSK or TKIP/CCMP; this mostly involves the 4-Way Handshake.
*/
/** List of WPA contexts in active use. */
struct list_head wpa_contexts = LIST_HEAD_INIT ( wpa_contexts );
/**
* Return an error code and deauthenticate
*
* @v ctx WPA common context
* @v rc Return status code
* @ret rc The passed return status code
*/
static int wpa_fail ( struct wpa_common_ctx *ctx, int rc )
{
net80211_deauthenticate ( ctx->dev, rc );
return rc;
}
/**
* Find a cryptosystem handler structure from a crypto ID
*
* @v crypt Cryptosystem ID
* @ret crypto Cryptosystem handler structure
*
* If support for @a crypt is not compiled in to gPXE, or if @a crypt
* is NET80211_CRYPT_UNKNOWN, returns @c NULL.
*/
static struct net80211_crypto *
wpa_find_cryptosystem ( enum net80211_crypto_alg crypt )
{
struct net80211_crypto *crypto;
for_each_table_entry ( crypto, NET80211_CRYPTOS ) {
if ( crypto->algorithm == crypt )
return crypto;
}
return NULL;
}
/**
* Find WPA key integrity and encryption handler from key version field
*
* @v ver Version bits of EAPOL-Key info field
* @ret kie Key integrity and encryption handler
*/
struct wpa_kie * wpa_find_kie ( int version )
{
struct wpa_kie *kie;
for_each_table_entry ( kie, WPA_KIES ) {
if ( kie->version == version )
return kie;
}
return NULL;
}
/**
* Construct RSN or WPA information element
*
* @v dev 802.11 device
* @ret ie_ret RSN or WPA information element
* @ret rc Return status code
*
* This function allocates, fills, and returns a RSN or WPA
* information element suitable for including in an association
* request frame to the network identified by @c dev->associating.
* If it is impossible to construct an information element consistent
* with gPXE's capabilities that is compatible with that network, or
* if none should be sent because that network's beacon included no
* security information, returns an error indication and leaves
* @a ie_ret unchanged.
*
* The returned IE will be of the same type (RSN or WPA) as was
* included in the beacon for the network it is destined for.
*/
int wpa_make_rsn_ie ( struct net80211_device *dev, union ieee80211_ie **ie_ret )
{
u8 *rsn, *rsn_end;
int is_rsn;
u32 group_cipher;
enum net80211_crypto_alg gcrypt;
int ie_len;
u8 *iep;
struct ieee80211_ie_rsn *ie;
struct ieee80211_frame *hdr;
struct ieee80211_beacon *beacon;
if ( ! dev->associating ) {
DBG ( "WPA: Can't make RSN IE for a non-associating device\n" );
return -EINVAL;
}
hdr = dev->associating->beacon->data;
beacon = ( struct ieee80211_beacon * ) hdr->data;
rsn = sec80211_find_rsn ( beacon->info_element,
dev->associating->beacon->tail, &is_rsn,
&rsn_end );
if ( ! rsn ) {
DBG ( "WPA: Can't make RSN IE when we didn't get one\n" );
return -EINVAL;
}
rsn += 2; /* skip version */
group_cipher = *( u32 * ) rsn;
gcrypt = sec80211_rsn_get_net80211_crypt ( group_cipher );
if ( ! wpa_find_cryptosystem ( gcrypt ) ||
! wpa_find_cryptosystem ( dev->associating->crypto ) ) {
DBG ( "WPA: No support for (GC:%d, PC:%d)\n",
gcrypt, dev->associating->crypto );
return -ENOTSUP;
}
/* Everything looks good - make our IE. */
/* WPA IEs need 4 more bytes for the OUI+type */
ie_len = ieee80211_rsn_size ( 1, 1, 0, is_rsn ) + ( 4 * ! is_rsn );
iep = malloc ( ie_len );
if ( ! iep )
return -ENOMEM;
*ie_ret = ( union ieee80211_ie * ) iep;
/* Store ID and length bytes. */
*iep++ = ( is_rsn ? IEEE80211_IE_RSN : IEEE80211_IE_VENDOR );
*iep++ = ie_len - 2;
/* Store OUI+type for WPA IEs. */
if ( ! is_rsn ) {
*( u32 * ) iep = IEEE80211_WPA_OUI_VEN;
iep += 4;
}
/* If this is a WPA IE, the id and len bytes in the
ieee80211_ie_rsn structure will not be valid, but by doing
the cast we can fill all the other fields much more
readily. */
ie = ( struct ieee80211_ie_rsn * ) ( iep - 2 );
ie->version = IEEE80211_RSN_VERSION;
ie->group_cipher = group_cipher;
ie->pairwise_count = 1;
ie->pairwise_cipher[0] =
sec80211_rsn_get_crypto_desc ( dev->associating->crypto,
is_rsn );
ie->akm_count = 1;
ie->akm_list[0] =
sec80211_rsn_get_akm_desc ( dev->associating->handshaking,
is_rsn );
if ( is_rsn ) {
ie->rsn_capab = 0;
ie->pmkid_count = 0;
}
return 0;
}
/**
* Set up generic WPA support to handle 4-Way Handshake
*
* @v dev 802.11 device
* @v ctx WPA common context
* @v pmk Pairwise Master Key to use for session
* @v pmk_len Length of PMK, almost always 32
* @ret rc Return status code
*/
int wpa_start ( struct net80211_device *dev, struct wpa_common_ctx *ctx,
const void *pmk, size_t pmk_len )
{
struct io_buffer *iob;
struct ieee80211_frame *hdr;
struct ieee80211_beacon *beacon;
u8 *ap_rsn_ie = NULL, *ap_rsn_ie_end;
if ( ! dev->rsn_ie || ! dev->associating )
return -EINVAL;
ctx->dev = dev;
memcpy ( ctx->pmk, pmk, ctx->pmk_len = pmk_len );
ctx->state = WPA_READY;
ctx->replay = ~0ULL;
iob = dev->associating->beacon;
hdr = iob->data;
beacon = ( struct ieee80211_beacon * ) hdr->data;
ap_rsn_ie = sec80211_find_rsn ( beacon->info_element, iob->tail,
&ctx->ap_rsn_is_rsn, &ap_rsn_ie_end );
if ( ap_rsn_ie ) {
ctx->ap_rsn_ie = malloc ( ap_rsn_ie_end - ap_rsn_ie );
if ( ! ctx->ap_rsn_ie )
return -ENOMEM;
memcpy ( ctx->ap_rsn_ie, ap_rsn_ie, ap_rsn_ie_end - ap_rsn_ie );
ctx->ap_rsn_ie_len = ap_rsn_ie_end - ap_rsn_ie;
} else {
return -ENOENT;
}
ctx->crypt = dev->associating->crypto;
ctx->gcrypt = NET80211_CRYPT_UNKNOWN;
list_add_tail ( &ctx->list, &wpa_contexts );
return 0;
}
/**
* Disable handling of received WPA handshake frames
*
* @v dev 802.11 device
*/
void wpa_stop ( struct net80211_device *dev )
{
struct wpa_common_ctx *ctx, *tmp;
list_for_each_entry_safe ( ctx, tmp, &wpa_contexts, list ) {
if ( ctx->dev == dev ) {
free ( ctx->ap_rsn_ie );
ctx->ap_rsn_ie = NULL;
list_del ( &ctx->list );
}
}
}
/**
* Check PMKID consistency
*
* @v ctx WPA common context
* @v pmkid PMKID to check against (16 bytes long)
* @ret rc Zero if they match, or a negative error code if not
*/
int wpa_check_pmkid ( struct wpa_common_ctx *ctx, const u8 *pmkid )
{
u8 sha1_ctx[SHA1_CTX_SIZE];
u8 my_pmkid[SHA1_SIZE];
u8 pmk[ctx->pmk_len];
size_t pmk_len;
struct {
char name[8];
u8 aa[ETH_ALEN];
u8 spa[ETH_ALEN];
} __attribute__ (( packed )) pmkid_data;
memcpy ( pmk, ctx->pmk, ctx->pmk_len );
pmk_len = ctx->pmk_len;
memcpy ( pmkid_data.name, "PMK Name", 8 );
memcpy ( pmkid_data.aa, ctx->dev->bssid, ETH_ALEN );
memcpy ( pmkid_data.spa, ctx->dev->netdev->ll_addr, ETH_ALEN );
hmac_init ( &sha1_algorithm, sha1_ctx, pmk, &pmk_len );
hmac_update ( &sha1_algorithm, sha1_ctx, &pmkid_data,
sizeof ( pmkid_data ) );
hmac_final ( &sha1_algorithm, sha1_ctx, pmk, &pmk_len, my_pmkid );
if ( memcmp ( my_pmkid, pmkid, WPA_PMKID_LEN ) != 0 )
return -EACCES;
return 0;
}
/**
* Derive pairwise transient key
*
* @v ctx WPA common context
*/
static void wpa_derive_ptk ( struct wpa_common_ctx *ctx )
{
struct {
u8 mac1[ETH_ALEN];
u8 mac2[ETH_ALEN];
u8 nonce1[WPA_NONCE_LEN];
u8 nonce2[WPA_NONCE_LEN];
} __attribute__ (( packed )) ptk_data;
/* The addresses and nonces are stored in numerical order (!) */
if ( memcmp ( ctx->dev->netdev->ll_addr, ctx->dev->bssid,
ETH_ALEN ) < 0 ) {
memcpy ( ptk_data.mac1, ctx->dev->netdev->ll_addr, ETH_ALEN );
memcpy ( ptk_data.mac2, ctx->dev->bssid, ETH_ALEN );
} else {
memcpy ( ptk_data.mac1, ctx->dev->bssid, ETH_ALEN );
memcpy ( ptk_data.mac2, ctx->dev->netdev->ll_addr, ETH_ALEN );
}
if ( memcmp ( ctx->Anonce, ctx->Snonce, WPA_NONCE_LEN ) < 0 ) {
memcpy ( ptk_data.nonce1, ctx->Anonce, WPA_NONCE_LEN );
memcpy ( ptk_data.nonce2, ctx->Snonce, WPA_NONCE_LEN );
} else {
memcpy ( ptk_data.nonce1, ctx->Snonce, WPA_NONCE_LEN );
memcpy ( ptk_data.nonce2, ctx->Anonce, WPA_NONCE_LEN );
}
DBGC2 ( ctx, "WPA %p A1 %s, A2 %s\n", ctx, eth_ntoa ( ptk_data.mac1 ),
eth_ntoa ( ptk_data.mac2 ) );
DBGC2 ( ctx, "WPA %p Nonce1, Nonce2:\n", ctx );
DBGC2_HD ( ctx, ptk_data.nonce1, WPA_NONCE_LEN );
DBGC2_HD ( ctx, ptk_data.nonce2, WPA_NONCE_LEN );
prf_sha1 ( ctx->pmk, ctx->pmk_len,
"Pairwise key expansion",
&ptk_data, sizeof ( ptk_data ),
&ctx->ptk, sizeof ( ctx->ptk ) );
DBGC2 ( ctx, "WPA %p PTK:\n", ctx );
DBGC2_HD ( ctx, &ctx->ptk, sizeof ( ctx->ptk ) );
}
/**
* Install pairwise transient key
*
* @v ctx WPA common context
* @v len Key length (16 for CCMP, 32 for TKIP)
* @ret rc Return status code
*/
static inline int wpa_install_ptk ( struct wpa_common_ctx *ctx, int len )
{
DBGC ( ctx, "WPA %p: installing %d-byte pairwise transient key\n",
ctx, len );
DBGC2_HD ( ctx, &ctx->ptk.tk, len );
return sec80211_install ( &ctx->dev->crypto, ctx->crypt,
&ctx->ptk.tk, len, NULL );
}
/**
* Install group transient key
*
* @v ctx WPA common context
* @v len Key length (16 for CCMP, 32 for TKIP)
* @v rsc Receive sequence counter field in EAPOL-Key packet
* @ret rc Return status code
*/
static inline int wpa_install_gtk ( struct wpa_common_ctx *ctx, int len,
const void *rsc )
{
DBGC ( ctx, "WPA %p: installing %d-byte group transient key\n",
ctx, len );
DBGC2_HD ( ctx, &ctx->gtk.tk, len );
return sec80211_install ( &ctx->dev->gcrypto, ctx->gcrypt,
&ctx->gtk.tk, len, rsc );
}
/**
* Search for group transient key, and install it if found
*
* @v ctx WPA common context
* @v ie Pointer to first IE in key data field
* @v ie_end Pointer to first byte not in key data field
* @v rsc Receive sequence counter field in EAPOL-Key packet
* @ret rc Return status code
*/
static int wpa_maybe_install_gtk ( struct wpa_common_ctx *ctx,
union ieee80211_ie *ie, void *ie_end,
const void *rsc )
{
struct wpa_kde *kde;
if ( ! ieee80211_ie_bound ( ie, ie_end ) )
return -ENOENT;
while ( ie ) {
if ( ie->id == IEEE80211_IE_VENDOR &&
ie->vendor.oui == WPA_KDE_GTK )
break;
ie = ieee80211_next_ie ( ie, ie_end );
}
if ( ! ie )
return -ENOENT;
if ( ie->len - 6u > sizeof ( ctx->gtk.tk ) ) {
DBGC ( ctx, "WPA %p: GTK KDE is too long (%d bytes, max %d)\n",
ctx, ie->len - 4, sizeof ( ctx->gtk.tk ) );
return -EINVAL;
}
/* XXX We ignore key ID for now. */
kde = ( struct wpa_kde * ) ie;
memcpy ( &ctx->gtk.tk, &kde->gtk_encap.gtk, kde->len - 6 );
return wpa_install_gtk ( ctx, kde->len - 6, rsc );
}
/**
* Allocate I/O buffer for construction of outgoing EAPOL-Key frame
*
* @v kdlen Maximum number of bytes in the Key Data field
* @ret iob Newly allocated I/O buffer
*
* The returned buffer will have space reserved for the link-layer and
* EAPOL headers, and will have @c iob->tail pointing to the start of
* the Key Data field. Thus, it is necessary to use iob_put() in
* filling the Key Data.
*/
static struct io_buffer * wpa_alloc_frame ( int kdlen )
{
struct io_buffer *ret = alloc_iob ( sizeof ( struct eapol_key_pkt ) +
kdlen + EAPOL_HDR_LEN +
MAX_LL_HEADER_LEN );
if ( ! ret )
return NULL;
iob_reserve ( ret, MAX_LL_HEADER_LEN + EAPOL_HDR_LEN );
memset ( iob_put ( ret, sizeof ( struct eapol_key_pkt ) ), 0,
sizeof ( struct eapol_key_pkt ) );
return ret;
}
/**
* Send EAPOL-Key packet
*
* @v iob I/O buffer, with sufficient headroom for headers
* @v dev 802.11 device
* @v kie Key integrity and encryption handler
* @v is_rsn If TRUE, handshake uses new RSN format
* @ret rc Return status code
*
* If a KIE is specified, the MIC will be filled in before transmission.
*/
static int wpa_send_eapol ( struct io_buffer *iob, struct wpa_common_ctx *ctx,
struct wpa_kie *kie )
{
struct eapol_key_pkt *pkt = iob->data;
struct eapol_frame *eapol = iob_push ( iob, EAPOL_HDR_LEN );
pkt->info = htons ( pkt->info );
pkt->keysize = htons ( pkt->keysize );
pkt->datalen = htons ( pkt->datalen );
pkt->replay = cpu_to_be64 ( pkt->replay );
eapol->version = EAPOL_THIS_VERSION;
eapol->type = EAPOL_TYPE_KEY;
eapol->length = htons ( iob->tail - iob->data - sizeof ( *eapol ) );
memset ( pkt->mic, 0, sizeof ( pkt->mic ) );
if ( kie )
kie->mic ( &ctx->ptk.kck, eapol, EAPOL_HDR_LEN +
sizeof ( *pkt ) + ntohs ( pkt->datalen ),
pkt->mic );
return net_tx ( iob, ctx->dev->netdev, &eapol_protocol,
ctx->dev->bssid );
}
/**
* Send second frame in 4-Way Handshake
*
* @v ctx WPA common context
* @v pkt First frame, to which this is a reply
* @v is_rsn If TRUE, handshake uses new RSN format
* @v kie Key integrity and encryption handler
* @ret rc Return status code
*/
static int wpa_send_2_of_4 ( struct wpa_common_ctx *ctx,
struct eapol_key_pkt *pkt, int is_rsn,
struct wpa_kie *kie )
{
struct io_buffer *iob = wpa_alloc_frame ( ctx->dev->rsn_ie->len + 2 );
struct eapol_key_pkt *npkt;
if ( ! iob )
return -ENOMEM;
npkt = iob->data;
memcpy ( npkt, pkt, sizeof ( *pkt ) );
npkt->info &= ~EAPOL_KEY_INFO_KEY_ACK;
npkt->info |= EAPOL_KEY_INFO_KEY_MIC;
if ( is_rsn )
npkt->keysize = 0;
memcpy ( npkt->nonce, ctx->Snonce, sizeof ( npkt->nonce ) );
npkt->datalen = ctx->dev->rsn_ie->len + 2;
memcpy ( iob_put ( iob, npkt->datalen ), ctx->dev->rsn_ie,
npkt->datalen );
DBGC ( ctx, "WPA %p: sending 2/4\n", ctx );
return wpa_send_eapol ( iob, ctx, kie );
}
/**
* Handle receipt of first frame in 4-Way Handshake
*
* @v ctx WPA common context
* @v pkt EAPOL-Key packet
* @v is_rsn If TRUE, frame uses new RSN format
* @v kie Key integrity and encryption handler
* @ret rc Return status code
*/
static int wpa_handle_1_of_4 ( struct wpa_common_ctx *ctx,
struct eapol_key_pkt *pkt, int is_rsn,
struct wpa_kie *kie )
{
int rc;
if ( ctx->state == WPA_WAITING )
return -EINVAL;
ctx->state = WPA_WORKING;
memcpy ( ctx->Anonce, pkt->nonce, sizeof ( ctx->Anonce ) );
if ( ! ctx->have_Snonce ) {
get_random_bytes ( ctx->Snonce, sizeof ( ctx->Snonce ) );
ctx->have_Snonce = 1;
}
if ( is_rsn && pkt->datalen ) {
union ieee80211_ie *ie = ( union ieee80211_ie * ) pkt->data;
void *ie_end = pkt->data + pkt->datalen;
if ( ! ieee80211_ie_bound ( ie, ie_end ) ) {
DBGC ( ctx, "WPA %p: malformed PMKID KDE\n", ctx );
return wpa_fail ( ctx, -EINVAL );
}
while ( ie ) {
if ( ie->id == IEEE80211_IE_VENDOR &&
ie->vendor.oui == WPA_KDE_PMKID ) {
rc = wpa_check_pmkid ( ctx, ie->vendor.data );
if ( rc < 0 ) {
DBGC ( ctx, "WPA %p ALERT: PMKID "
"mismatch in 1/4\n", ctx );
return wpa_fail ( ctx, rc );
}
}
ie = ieee80211_next_ie ( ie, ie_end );
}
}
DBGC ( ctx, "WPA %p: received 1/4, looks OK\n", ctx );
wpa_derive_ptk ( ctx );
return wpa_send_2_of_4 ( ctx, pkt, is_rsn, kie );
}
/**
* Send fourth frame in 4-Way Handshake, or second in Group Key Handshake
*
* @v ctx WPA common context
* @v pkt EAPOL-Key packet for frame to which we're replying
* @v is_rsn If TRUE, frame uses new RSN format
* @v kie Key integrity and encryption handler
* @ret rc Return status code
*/
static int wpa_send_final ( struct wpa_common_ctx *ctx,
struct eapol_key_pkt *pkt, int is_rsn,
struct wpa_kie *kie )
{
struct io_buffer *iob = wpa_alloc_frame ( 0 );
struct eapol_key_pkt *npkt;
if ( ! iob )
return -ENOMEM;
npkt = iob->data;
memcpy ( npkt, pkt, sizeof ( *pkt ) );
npkt->info &= ~( EAPOL_KEY_INFO_KEY_ACK | EAPOL_KEY_INFO_INSTALL |
EAPOL_KEY_INFO_KEY_ENC );
if ( is_rsn )
npkt->keysize = 0;
memset ( npkt->nonce, 0, sizeof ( npkt->nonce ) );
memset ( npkt->iv, 0, sizeof ( npkt->iv ) );
npkt->datalen = 0;
if ( npkt->info & EAPOL_KEY_INFO_TYPE )
DBGC ( ctx, "WPA %p: sending 4/4\n", ctx );
else
DBGC ( ctx, "WPA %p: sending 2/2\n", ctx );
return wpa_send_eapol ( iob, ctx, kie );
}
/**
* Handle receipt of third frame in 4-Way Handshake
*
* @v ctx WPA common context
* @v pkt EAPOL-Key packet
* @v is_rsn If TRUE, frame uses new RSN format
* @v kie Key integrity and encryption handler
* @ret rc Return status code
*/
static int wpa_handle_3_of_4 ( struct wpa_common_ctx *ctx,
struct eapol_key_pkt *pkt, int is_rsn,
struct wpa_kie *kie )
{
int rc;
u8 *this_rsn, *this_rsn_end;
u8 *new_rsn, *new_rsn_end;
int this_is_rsn, new_is_rsn;
if ( ctx->state == WPA_WAITING )
return -EINVAL;
ctx->state = WPA_WORKING;
/* Check nonce */
if ( memcmp ( ctx->Anonce, pkt->nonce, WPA_NONCE_LEN ) != 0 ) {
DBGC ( ctx, "WPA %p ALERT: nonce mismatch in 3/4\n", ctx );
return wpa_fail ( ctx, -EACCES );
}
/* Check RSN IE */
this_rsn = sec80211_find_rsn ( ( union ieee80211_ie * ) pkt->data,
pkt->data + pkt->datalen,
&this_is_rsn, &this_rsn_end );
if ( this_rsn )
new_rsn = sec80211_find_rsn ( ( union ieee80211_ie * )
this_rsn_end,
pkt->data + pkt->datalen,
&new_is_rsn, &new_rsn_end );
else
new_rsn = NULL;
if ( ! ctx->ap_rsn_ie || ! this_rsn ||
ctx->ap_rsn_ie_len != ( this_rsn_end - this_rsn ) ||
ctx->ap_rsn_is_rsn != this_is_rsn ||
memcmp ( ctx->ap_rsn_ie, this_rsn, ctx->ap_rsn_ie_len ) != 0 ) {
DBGC ( ctx, "WPA %p ALERT: RSN mismatch in 3/4\n", ctx );
DBGC2 ( ctx, "WPA %p RSNs (in 3/4, in beacon):\n", ctx );
DBGC2_HD ( ctx, this_rsn, this_rsn_end - this_rsn );
DBGC2_HD ( ctx, ctx->ap_rsn_ie, ctx->ap_rsn_ie_len );
return wpa_fail ( ctx, -EACCES );
}
/* Don't switch if they just supplied both styles of IE
simultaneously; we need two RSN IEs or two WPA IEs to
switch ciphers. They'll be immediately consecutive because
of ordering guarantees. */
if ( new_rsn && this_is_rsn == new_is_rsn ) {
struct net80211_wlan *assoc = ctx->dev->associating;
DBGC ( ctx, "WPA %p: accommodating bait-and-switch tactics\n",
ctx );
DBGC2 ( ctx, "WPA %p RSNs (in 3/4+beacon, new in 3/4):\n",
ctx );
DBGC2_HD ( ctx, this_rsn, this_rsn_end - this_rsn );
DBGC2_HD ( ctx, new_rsn, new_rsn_end - new_rsn );
if ( ( rc = sec80211_detect_ie ( new_is_rsn, new_rsn,
new_rsn_end,
&assoc->handshaking,
&assoc->crypto ) ) != 0 )
DBGC ( ctx, "WPA %p: bait-and-switch invalid, staying "
"with original request\n", ctx );
} else {
new_rsn = this_rsn;
new_is_rsn = this_is_rsn;
new_rsn_end = this_rsn_end;
}
/* Grab group cryptosystem ID */
ctx->gcrypt = sec80211_rsn_get_net80211_crypt ( *( u32 * )
( new_rsn + 2 ) );
/* Check for a GTK, if info field is encrypted */
if ( pkt->info & EAPOL_KEY_INFO_KEY_ENC ) {
rc = wpa_maybe_install_gtk ( ctx,
( union ieee80211_ie * ) pkt->data,
pkt->data + pkt->datalen,
pkt->rsc );
if ( rc < 0 ) {
DBGC ( ctx, "WPA %p did not install GTK in 3/4: %s\n",
ctx, strerror ( rc ) );
if ( rc != -ENOENT )
return wpa_fail ( ctx, rc );
}
}
DBGC ( ctx, "WPA %p: received 3/4, looks OK\n", ctx );
/* Send final message */
rc = wpa_send_final ( ctx, pkt, is_rsn, kie );
if ( rc < 0 )
return wpa_fail ( ctx, rc );
/* Install PTK */
rc = wpa_install_ptk ( ctx, pkt->keysize );
if ( rc < 0 ) {
DBGC ( ctx, "WPA %p failed to install PTK: %s\n", ctx,
strerror ( rc ) );
return wpa_fail ( ctx, rc );
}
/* Mark us as needing a new Snonce if we rekey */
ctx->have_Snonce = 0;
/* Done! */
ctx->state = WPA_SUCCESS;
return 0;
}
/**
* Handle receipt of first frame in Group Key Handshake
*
* @v ctx WPA common context
* @v pkt EAPOL-Key packet
* @v is_rsn If TRUE, frame uses new RSN format
* @v kie Key integrity and encryption handler
* @ret rc Return status code
*/
static int wpa_handle_1_of_2 ( struct wpa_common_ctx *ctx,
struct eapol_key_pkt *pkt, int is_rsn,
struct wpa_kie *kie )
{
int rc;
/*
* WPA and RSN do this completely differently.
*
* The idea of encoding the GTK (or PMKID, or various other
* things) into a KDE that looks like an information element
* is an RSN innovation; old WPA code never encapsulates
* things like that. If it looks like an info element, it
* really is (for the WPA IE check in frames 2/4 and 3/4). The
* "key data encrypted" bit in the info field is also specific
* to RSN.
*
* So from an old WPA host, 3/4 does not contain an
* encapsulated GTK. The first frame of the GK handshake
* contains it, encrypted, but without a KDE wrapper, and with
* the key ID field (which gPXE doesn't use) shoved away in
* the reserved bits in the info field, and the TxRx bit
* stealing the Install bit's spot.
*/
if ( is_rsn && ( pkt->info & EAPOL_KEY_INFO_KEY_ENC ) ) {
rc = wpa_maybe_install_gtk ( ctx,
( union ieee80211_ie * ) pkt->data,
pkt->data + pkt->datalen,
pkt->rsc );
if ( rc < 0 ) {
DBGC ( ctx, "WPA %p: failed to install GTK in 1/2: "
"%s\n", ctx, strerror ( rc ) );
return wpa_fail ( ctx, rc );
}
} else {
rc = kie->decrypt ( &ctx->ptk.kek, pkt->iv, pkt->data,
&pkt->datalen );
if ( rc < 0 ) {
DBGC ( ctx, "WPA %p: failed to decrypt GTK: %s\n",
ctx, strerror ( rc ) );
return rc; /* non-fatal */
}
if ( pkt->datalen > sizeof ( ctx->gtk.tk ) ) {
DBGC ( ctx, "WPA %p: too much GTK data (%d > %d)\n",
ctx, pkt->datalen, sizeof ( ctx->gtk.tk ) );
return wpa_fail ( ctx, -EINVAL );
}
memcpy ( &ctx->gtk.tk, pkt->data, pkt->datalen );
wpa_install_gtk ( ctx, pkt->datalen, pkt->rsc );
}
DBGC ( ctx, "WPA %p: received 1/2, looks OK\n", ctx );
return wpa_send_final ( ctx, pkt, is_rsn, kie );
}
/**
* Handle receipt of EAPOL-Key frame for WPA
*
* @v iob I/O buffer
* @v netdev Network device
* @v ll_source Source link-layer address
*/
static int eapol_key_rx ( struct io_buffer *iob, struct net_device *netdev,
const void *ll_source )
{
struct net80211_device *dev = net80211_get ( netdev );
struct eapol_key_pkt *pkt = iob->data;
int is_rsn, found_ctx;
struct wpa_common_ctx *ctx;
int rc = 0;
struct wpa_kie *kie;
u8 their_mic[16], our_mic[16];
if ( pkt->type != EAPOL_KEY_TYPE_WPA &&
pkt->type != EAPOL_KEY_TYPE_RSN ) {
DBG ( "EAPOL-Key: packet not of 802.11 type\n" );
rc = -EINVAL;
goto drop;
}
is_rsn = ( pkt->type == EAPOL_KEY_TYPE_RSN );
if ( ! dev ) {
DBG ( "EAPOL-Key: packet not from 802.11\n" );
rc = -EINVAL;
goto drop;
}
if ( memcmp ( dev->bssid, ll_source, ETH_ALEN ) != 0 ) {
DBG ( "EAPOL-Key: packet not from associated AP\n" );
rc = -EINVAL;
goto drop;
}
if ( ! ( ntohs ( pkt->info ) & EAPOL_KEY_INFO_KEY_ACK ) ) {
DBG ( "EAPOL-Key: packet sent in wrong direction\n" );
rc = -EINVAL;
goto drop;
}
found_ctx = 0;
list_for_each_entry ( ctx, &wpa_contexts, list ) {
if ( ctx->dev == dev ) {
found_ctx = 1;
break;
}
}
if ( ! found_ctx ) {
DBG ( "EAPOL-Key: no WPA context to handle packet for %p\n",
dev );
rc = -ENOENT;
goto drop;
}
if ( ( void * ) ( pkt + 1 ) + ntohs ( pkt->datalen ) > iob->tail ) {
DBGC ( ctx, "WPA %p: packet truncated (has %d extra bytes, "
"states %d)\n", ctx, iob->tail - ( void * ) ( pkt + 1 ),
ntohs ( pkt->datalen ) );
rc = -EINVAL;
goto drop;
}
/* Get a handle on key integrity/encryption handler */
kie = wpa_find_kie ( ntohs ( pkt->info ) & EAPOL_KEY_INFO_VERSION );
if ( ! kie ) {
DBGC ( ctx, "WPA %p: no support for packet version %d\n", ctx,
ntohs ( pkt->info ) & EAPOL_KEY_INFO_VERSION );
rc = wpa_fail ( ctx, -ENOTSUP );
goto drop;
}
/* Check MIC */
if ( ntohs ( pkt->info ) & EAPOL_KEY_INFO_KEY_MIC ) {
memcpy ( their_mic, pkt->mic, sizeof ( pkt->mic ) );
memset ( pkt->mic, 0, sizeof ( pkt->mic ) );
kie->mic ( &ctx->ptk.kck, ( void * ) pkt - EAPOL_HDR_LEN,
EAPOL_HDR_LEN + sizeof ( *pkt ) +
ntohs ( pkt->datalen ), our_mic );
DBGC2 ( ctx, "WPA %p MIC comparison (theirs, ours):\n", ctx );
DBGC2_HD ( ctx, their_mic, 16 );
DBGC2_HD ( ctx, our_mic, 16 );
if ( memcmp ( their_mic, our_mic, sizeof ( pkt->mic ) ) != 0 ) {
DBGC ( ctx, "WPA %p: EAPOL MIC failure\n", ctx );
goto drop;
}
}
/* Fix byte order to local */
pkt->info = ntohs ( pkt->info );
pkt->keysize = ntohs ( pkt->keysize );
pkt->datalen = ntohs ( pkt->datalen );
pkt->replay = be64_to_cpu ( pkt->replay );
/* Check replay counter */
if ( ctx->replay != ~0ULL && ctx->replay >= pkt->replay ) {
DBGC ( ctx, "WPA %p ALERT: Replay detected! "
"(%08x:%08x >= %08x:%08x)\n", ctx,
( u32 ) ( ctx->replay >> 32 ), ( u32 ) ctx->replay,
( u32 ) ( pkt->replay >> 32 ), ( u32 ) pkt->replay );
rc = 0; /* ignore without error */
goto drop;
}
ctx->replay = pkt->replay;
/* Decrypt key data */
if ( pkt->info & EAPOL_KEY_INFO_KEY_ENC ) {
rc = kie->decrypt ( &ctx->ptk.kek, pkt->iv, pkt->data,
&pkt->datalen );
if ( rc < 0 ) {
DBGC ( ctx, "WPA %p: failed to decrypt packet: %s\n",
ctx, strerror ( rc ) );
goto drop;
}
}
/* Hand it off to appropriate handler */
switch ( pkt->info & ( EAPOL_KEY_INFO_TYPE |
EAPOL_KEY_INFO_KEY_MIC ) ) {
case EAPOL_KEY_TYPE_PTK:
rc = wpa_handle_1_of_4 ( ctx, pkt, is_rsn, kie );
break;
case EAPOL_KEY_TYPE_PTK | EAPOL_KEY_INFO_KEY_MIC:
rc = wpa_handle_3_of_4 ( ctx, pkt, is_rsn, kie );
break;
case EAPOL_KEY_TYPE_GTK | EAPOL_KEY_INFO_KEY_MIC:
rc = wpa_handle_1_of_2 ( ctx, pkt, is_rsn, kie );
break;
default:
DBGC ( ctx, "WPA %p: Invalid combination of key flags %04x\n",
ctx, pkt->info );
rc = -EINVAL;
break;
}
drop:
free_iob ( iob );
return rc;
}
struct eapol_handler eapol_key_handler __eapol_handler = {
.type = EAPOL_TYPE_KEY,
.rx = eapol_key_rx,
};
/* WPA always needs EAPOL in order to be useful */
REQUIRE_OBJECT ( eapol );