kernel-ark/net/mac80211/wep.c
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00

342 lines
8.9 KiB
C

/*
* Software WEP encryption implementation
* Copyright 2002, Jouni Malinen <jkmaline@cc.hut.fi>
* Copyright 2003, Instant802 Networks, 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.
*/
#include <linux/netdevice.h>
#include <linux/types.h>
#include <linux/random.h>
#include <linux/compiler.h>
#include <linux/crc32.h>
#include <linux/crypto.h>
#include <linux/err.h>
#include <linux/mm.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>
#include <asm/unaligned.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"
#include "wep.h"
int ieee80211_wep_init(struct ieee80211_local *local)
{
/* start WEP IV from a random value */
get_random_bytes(&local->wep_iv, WEP_IV_LEN);
local->wep_tx_tfm = crypto_alloc_blkcipher("ecb(arc4)", 0,
CRYPTO_ALG_ASYNC);
if (IS_ERR(local->wep_tx_tfm))
return PTR_ERR(local->wep_tx_tfm);
local->wep_rx_tfm = crypto_alloc_blkcipher("ecb(arc4)", 0,
CRYPTO_ALG_ASYNC);
if (IS_ERR(local->wep_rx_tfm)) {
crypto_free_blkcipher(local->wep_tx_tfm);
return PTR_ERR(local->wep_rx_tfm);
}
return 0;
}
void ieee80211_wep_free(struct ieee80211_local *local)
{
crypto_free_blkcipher(local->wep_tx_tfm);
crypto_free_blkcipher(local->wep_rx_tfm);
}
static inline bool ieee80211_wep_weak_iv(u32 iv, int keylen)
{
/*
* Fluhrer, Mantin, and Shamir have reported weaknesses in the
* key scheduling algorithm of RC4. At least IVs (KeyByte + 3,
* 0xff, N) can be used to speedup attacks, so avoid using them.
*/
if ((iv & 0xff00) == 0xff00) {
u8 B = (iv >> 16) & 0xff;
if (B >= 3 && B < 3 + keylen)
return true;
}
return false;
}
static void ieee80211_wep_get_iv(struct ieee80211_local *local,
int keylen, int keyidx, u8 *iv)
{
local->wep_iv++;
if (ieee80211_wep_weak_iv(local->wep_iv, keylen))
local->wep_iv += 0x0100;
if (!iv)
return;
*iv++ = (local->wep_iv >> 16) & 0xff;
*iv++ = (local->wep_iv >> 8) & 0xff;
*iv++ = local->wep_iv & 0xff;
*iv++ = keyidx << 6;
}
static u8 *ieee80211_wep_add_iv(struct ieee80211_local *local,
struct sk_buff *skb,
int keylen, int keyidx)
{
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
unsigned int hdrlen;
u8 *newhdr;
hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
if (WARN_ON(skb_tailroom(skb) < WEP_ICV_LEN ||
skb_headroom(skb) < WEP_IV_LEN))
return NULL;
hdrlen = ieee80211_hdrlen(hdr->frame_control);
newhdr = skb_push(skb, WEP_IV_LEN);
memmove(newhdr, newhdr + WEP_IV_LEN, hdrlen);
ieee80211_wep_get_iv(local, keylen, keyidx, newhdr + hdrlen);
return newhdr + hdrlen;
}
static void ieee80211_wep_remove_iv(struct ieee80211_local *local,
struct sk_buff *skb,
struct ieee80211_key *key)
{
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
unsigned int hdrlen;
hdrlen = ieee80211_hdrlen(hdr->frame_control);
memmove(skb->data + WEP_IV_LEN, skb->data, hdrlen);
skb_pull(skb, WEP_IV_LEN);
}
/* Perform WEP encryption using given key. data buffer must have tailroom
* for 4-byte ICV. data_len must not include this ICV. Note: this function
* does _not_ add IV. data = RC4(data | CRC32(data)) */
void ieee80211_wep_encrypt_data(struct crypto_blkcipher *tfm, u8 *rc4key,
size_t klen, u8 *data, size_t data_len)
{
struct blkcipher_desc desc = { .tfm = tfm };
struct scatterlist sg;
__le32 icv;
icv = cpu_to_le32(~crc32_le(~0, data, data_len));
put_unaligned(icv, (__le32 *)(data + data_len));
crypto_blkcipher_setkey(tfm, rc4key, klen);
sg_init_one(&sg, data, data_len + WEP_ICV_LEN);
crypto_blkcipher_encrypt(&desc, &sg, &sg, sg.length);
}
/* Perform WEP encryption on given skb. 4 bytes of extra space (IV) in the
* beginning of the buffer 4 bytes of extra space (ICV) in the end of the
* buffer will be added. Both IV and ICV will be transmitted, so the
* payload length increases with 8 bytes.
*
* WEP frame payload: IV + TX key idx, RC4(data), ICV = RC4(CRC32(data))
*/
int ieee80211_wep_encrypt(struct ieee80211_local *local,
struct sk_buff *skb,
const u8 *key, int keylen, int keyidx)
{
u8 *iv;
size_t len;
u8 rc4key[3 + WLAN_KEY_LEN_WEP104];
iv = ieee80211_wep_add_iv(local, skb, keylen, keyidx);
if (!iv)
return -1;
len = skb->len - (iv + WEP_IV_LEN - skb->data);
/* Prepend 24-bit IV to RC4 key */
memcpy(rc4key, iv, 3);
/* Copy rest of the WEP key (the secret part) */
memcpy(rc4key + 3, key, keylen);
/* Add room for ICV */
skb_put(skb, WEP_ICV_LEN);
ieee80211_wep_encrypt_data(local->wep_tx_tfm, rc4key, keylen + 3,
iv + WEP_IV_LEN, len);
return 0;
}
/* Perform WEP decryption using given key. data buffer includes encrypted
* payload, including 4-byte ICV, but _not_ IV. data_len must not include ICV.
* Return 0 on success and -1 on ICV mismatch. */
int ieee80211_wep_decrypt_data(struct crypto_blkcipher *tfm, u8 *rc4key,
size_t klen, u8 *data, size_t data_len)
{
struct blkcipher_desc desc = { .tfm = tfm };
struct scatterlist sg;
__le32 crc;
crypto_blkcipher_setkey(tfm, rc4key, klen);
sg_init_one(&sg, data, data_len + WEP_ICV_LEN);
crypto_blkcipher_decrypt(&desc, &sg, &sg, sg.length);
crc = cpu_to_le32(~crc32_le(~0, data, data_len));
if (memcmp(&crc, data + data_len, WEP_ICV_LEN) != 0)
/* ICV mismatch */
return -1;
return 0;
}
/* Perform WEP decryption on given skb. Buffer includes whole WEP part of
* the frame: IV (4 bytes), encrypted payload (including SNAP header),
* ICV (4 bytes). skb->len includes both IV and ICV.
*
* Returns 0 if frame was decrypted successfully and ICV was correct and -1 on
* failure. If frame is OK, IV and ICV will be removed, i.e., decrypted payload
* is moved to the beginning of the skb and skb length will be reduced.
*/
static int ieee80211_wep_decrypt(struct ieee80211_local *local,
struct sk_buff *skb,
struct ieee80211_key *key)
{
u32 klen;
u8 *rc4key;
u8 keyidx;
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
unsigned int hdrlen;
size_t len;
int ret = 0;
if (!ieee80211_has_protected(hdr->frame_control))
return -1;
hdrlen = ieee80211_hdrlen(hdr->frame_control);
if (skb->len < hdrlen + WEP_IV_LEN + WEP_ICV_LEN)
return -1;
len = skb->len - hdrlen - WEP_IV_LEN - WEP_ICV_LEN;
keyidx = skb->data[hdrlen + 3] >> 6;
if (!key || keyidx != key->conf.keyidx || key->conf.alg != ALG_WEP)
return -1;
klen = 3 + key->conf.keylen;
rc4key = kmalloc(klen, GFP_ATOMIC);
if (!rc4key)
return -1;
/* Prepend 24-bit IV to RC4 key */
memcpy(rc4key, skb->data + hdrlen, 3);
/* Copy rest of the WEP key (the secret part) */
memcpy(rc4key + 3, key->conf.key, key->conf.keylen);
if (ieee80211_wep_decrypt_data(local->wep_rx_tfm, rc4key, klen,
skb->data + hdrlen + WEP_IV_LEN,
len))
ret = -1;
kfree(rc4key);
/* Trim ICV */
skb_trim(skb, skb->len - WEP_ICV_LEN);
/* Remove IV */
memmove(skb->data + WEP_IV_LEN, skb->data, hdrlen);
skb_pull(skb, WEP_IV_LEN);
return ret;
}
bool ieee80211_wep_is_weak_iv(struct sk_buff *skb, struct ieee80211_key *key)
{
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
unsigned int hdrlen;
u8 *ivpos;
u32 iv;
if (!ieee80211_has_protected(hdr->frame_control))
return false;
hdrlen = ieee80211_hdrlen(hdr->frame_control);
ivpos = skb->data + hdrlen;
iv = (ivpos[0] << 16) | (ivpos[1] << 8) | ivpos[2];
return ieee80211_wep_weak_iv(iv, key->conf.keylen);
}
ieee80211_rx_result
ieee80211_crypto_wep_decrypt(struct ieee80211_rx_data *rx)
{
struct sk_buff *skb = rx->skb;
struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
if (!ieee80211_is_data(hdr->frame_control) &&
!ieee80211_is_auth(hdr->frame_control))
return RX_CONTINUE;
if (!(status->flag & RX_FLAG_DECRYPTED)) {
if (ieee80211_wep_decrypt(rx->local, rx->skb, rx->key))
return RX_DROP_UNUSABLE;
} else if (!(status->flag & RX_FLAG_IV_STRIPPED)) {
ieee80211_wep_remove_iv(rx->local, rx->skb, rx->key);
/* remove ICV */
skb_trim(rx->skb, rx->skb->len - WEP_ICV_LEN);
}
return RX_CONTINUE;
}
static int wep_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
{
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
if (!info->control.hw_key) {
if (ieee80211_wep_encrypt(tx->local, skb, tx->key->conf.key,
tx->key->conf.keylen,
tx->key->conf.keyidx))
return -1;
} else if (info->control.hw_key->flags &
IEEE80211_KEY_FLAG_GENERATE_IV) {
if (!ieee80211_wep_add_iv(tx->local, skb,
tx->key->conf.keylen,
tx->key->conf.keyidx))
return -1;
}
return 0;
}
ieee80211_tx_result
ieee80211_crypto_wep_encrypt(struct ieee80211_tx_data *tx)
{
struct sk_buff *skb;
ieee80211_tx_set_protected(tx);
skb = tx->skb;
do {
if (wep_encrypt_skb(tx, skb) < 0) {
I802_DEBUG_INC(tx->local->tx_handlers_drop_wep);
return TX_DROP;
}
} while ((skb = skb->next));
return TX_CONTINUE;
}