key.h

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/*
 * 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>

#define NUM_DEFAULT_KEYS 4
#define NUM_DEFAULT_MGMT_KEYS 2

#define WEP_IV_LEN      4
#define WEP_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 TKIP_IV_LEN     8
#define TKIP_ICV_LEN        4
#define CMAC_PN_LEN     6

#define NUM_RX_DATA_QUEUES  16

struct ieee80211_local;
struct ieee80211_sub_if_data;
struct sta_info;

enum ieee80211_internal_key_flags {
    KEY_FLAG_UPLOADED_TO_HARDWARE   = BIT(0),
    KEY_FLAG_TAINTED        = BIT(1),
};

enum ieee80211_internal_tkip_state {
    TKIP_STATE_NOT_INIT,
    TKIP_STATE_PHASE1_DONE,
    TKIP_STATE_PHASE1_HW_UPLOADED,
};

struct tkip_ctx {
    u32 iv32;   /* current iv32 */
    u16 iv16;   /* current iv16 */
    u16 p1k[5]; /* p1k cache */
    u32 p1k_iv32;   /* iv32 for which p1k computed */
    enum ieee80211_internal_tkip_state state;
};

struct ieee80211_key {
    struct ieee80211_local *local;
    struct ieee80211_sub_if_data *sdata;
    struct sta_info *sta;

    /* for sdata list */
    struct list_head list;

    /* protected by key mutex */
    unsigned int flags;

    union {
        struct {
            /* protects tx context */
            spinlock_t txlock;

            /* last used TSC */
            struct tkip_ctx tx;

            /* last received RSC */
            struct tkip_ctx rx[NUM_RX_DATA_QUEUES];
        } tkip;
        struct {
            atomic64_t tx_pn;
            /*
             * Last received packet number. The first
             * NUM_RX_DATA_QUEUES counters are used with Data
             * frames and the last counter is used with Robust
             * Management frames.
             */
            u8 rx_pn[NUM_RX_DATA_QUEUES + 1][CCMP_PN_LEN];
            struct crypto_cipher *tfm;
            u32 replays; /* dot11RSNAStatsCCMPReplays */
        } ccmp;
        struct {
            atomic64_t tx_pn;
            u8 rx_pn[CMAC_PN_LEN];
            struct crypto_cipher *tfm;
            u32 replays; /* dot11RSNAStatsCMACReplays */
            u32 icverrors; /* dot11RSNAStatsCMACICVErrors */
        } aes_cmac;
    } u;

    /* number of times this key has been used */
    int tx_rx_count;

#ifdef CONFIG_MAC80211_DEBUGFS
    struct {
        struct dentry *stalink;
        struct dentry *dir;
        int cnt;
    } 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(u32 cipher, int idx, size_t key_len,
                      const u8 *key_data,
                      size_t seq_len, const u8 *seq);
/*
 * Insert a key into data structures (sdata, sta if necessary)
 * to make it used, free old key.
 */
int __must_check 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_key_free(struct ieee80211_local *local,
            struct ieee80211_key *key);
void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
                   bool uni, bool multi);
void ieee80211_set_default_mgmt_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);

#define key_mtx_dereference(local, ref) \
    rcu_dereference_protected(ref, lockdep_is_held(&((local)->key_mtx)))

#endif /* IEEE80211_KEY_H */