linux/net/mac80211/ieee80211_key.h
Johannes Berg db4d1169d0 mac80211: split ieee80211_key_alloc/free
In order to RCU-ify sta_info, we need to be able to allocate
a key without linking it to an sdata/sta structure (because
allocation cannot be done in an rcu critical section). This
patch splits up ieee80211_key_alloc() and updates all users
appropriately.

While at it, this patch fixes a number of race conditions
such as finally making key replacement atomic, unfortunately
at the expense of more complex code.

Note that this patch documents /existing/ bugs with sta info
and key interaction, there is currently a race condition
when a sta info is freed without holding the RTNL. This will
finally be fixed by a followup patch.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-02-29 15:42:04 -05:00

146 lines
3.7 KiB
C

/*
* Copyright 2002-2004, Instant802 Networks, Inc.
* Copyright 2005, Devicescape Software, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef IEEE80211_KEY_H
#define IEEE80211_KEY_H
#include <linux/types.h>
#include <linux/list.h>
#include <linux/crypto.h>
#include <linux/rcupdate.h>
#include <net/mac80211.h>
/* ALG_TKIP
* struct ieee80211_key::key is encoded as a 256-bit (32 byte) data block:
* Temporal Encryption Key (128 bits)
* Temporal Authenticator Tx MIC Key (64 bits)
* Temporal Authenticator Rx MIC Key (64 bits)
*/
#define WEP_IV_LEN 4
#define WEP_ICV_LEN 4
#define ALG_TKIP_KEY_LEN 32
/* Starting offsets for each key */
#define ALG_TKIP_TEMP_ENCR_KEY 0
#define ALG_TKIP_TEMP_AUTH_TX_MIC_KEY 16
#define ALG_TKIP_TEMP_AUTH_RX_MIC_KEY 24
#define TKIP_IV_LEN 8
#define TKIP_ICV_LEN 4
#define ALG_CCMP_KEY_LEN 16
#define CCMP_HDR_LEN 8
#define CCMP_MIC_LEN 8
#define CCMP_TK_LEN 16
#define CCMP_PN_LEN 6
#define NUM_RX_DATA_QUEUES 17
struct ieee80211_local;
struct ieee80211_sub_if_data;
struct sta_info;
/**
* enum ieee80211_internal_key_flags - internal key flags
*
* @KEY_FLAG_UPLOADED_TO_HARDWARE: Indicates that this key is present
* in the hardware for TX crypto hardware acceleration.
* @KEY_FLAG_REMOVE_FROM_HARDWARE: Indicates to the key code that this
* key is present in the hardware (but it cannot be used for
* hardware acceleration any more!)
*/
enum ieee80211_internal_key_flags {
KEY_FLAG_UPLOADED_TO_HARDWARE = BIT(0),
KEY_FLAG_REMOVE_FROM_HARDWARE = BIT(1),
};
struct ieee80211_key {
struct ieee80211_local *local;
struct ieee80211_sub_if_data *sdata;
struct sta_info *sta;
struct list_head list;
unsigned int flags;
union {
struct {
/* last used TSC */
u32 iv32;
u16 iv16;
u16 p1k[5];
int tx_initialized;
/* last received RSC */
u32 iv32_rx[NUM_RX_DATA_QUEUES];
u16 iv16_rx[NUM_RX_DATA_QUEUES];
u16 p1k_rx[NUM_RX_DATA_QUEUES][5];
int rx_initialized[NUM_RX_DATA_QUEUES];
} tkip;
struct {
u8 tx_pn[6];
u8 rx_pn[NUM_RX_DATA_QUEUES][6];
struct crypto_cipher *tfm;
u32 replays; /* dot11RSNAStatsCCMPReplays */
/* scratch buffers for virt_to_page() (crypto API) */
#ifndef AES_BLOCK_LEN
#define AES_BLOCK_LEN 16
#endif
u8 tx_crypto_buf[6 * AES_BLOCK_LEN];
u8 rx_crypto_buf[6 * AES_BLOCK_LEN];
} ccmp;
} u;
/* number of times this key has been used */
int tx_rx_count;
#ifdef CONFIG_MAC80211_DEBUGFS
struct {
struct dentry *stalink;
struct dentry *dir;
struct dentry *keylen;
struct dentry *flags;
struct dentry *keyidx;
struct dentry *hw_key_idx;
struct dentry *tx_rx_count;
struct dentry *algorithm;
struct dentry *tx_spec;
struct dentry *rx_spec;
struct dentry *replays;
struct dentry *key;
struct dentry *ifindex;
} debugfs;
#endif
/*
* key config, must be last because it contains key
* material as variable length member
*/
struct ieee80211_key_conf conf;
};
struct ieee80211_key *ieee80211_key_alloc(enum ieee80211_key_alg alg,
int idx,
size_t key_len,
const u8 *key_data);
/*
* Insert a key into data structures (sdata, sta if necessary)
* to make it used, free old key.
*/
void ieee80211_key_link(struct ieee80211_key *key,
struct ieee80211_sub_if_data *sdata,
struct sta_info *sta);
void ieee80211_key_free(struct ieee80211_key *key);
void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx);
void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata);
void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata);
void ieee80211_disable_keys(struct ieee80211_sub_if_data *sdata);
#endif /* IEEE80211_KEY_H */