lib80211: don't use skcipher

Using skcipher just makes the code longer, and mac80211
also "open-codes" the WEP encrypt/decrypt.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Johannes Berg 2018-10-01 09:16:08 +02:00
parent 1edcfc20c9
commit b802a5d6f3
2 changed files with 40 additions and 71 deletions

View File

@ -30,7 +30,7 @@
#include <net/iw_handler.h>
#include <crypto/hash.h>
#include <crypto/skcipher.h>
#include <linux/crypto.h>
#include <linux/crc32.h>
#include <net/lib80211.h>
@ -64,9 +64,9 @@ struct lib80211_tkip_data {
int key_idx;
struct crypto_skcipher *rx_tfm_arc4;
struct crypto_cipher *rx_tfm_arc4;
struct crypto_shash *rx_tfm_michael;
struct crypto_skcipher *tx_tfm_arc4;
struct crypto_cipher *tx_tfm_arc4;
struct crypto_shash *tx_tfm_michael;
/* scratch buffers for virt_to_page() (crypto API) */
@ -99,8 +99,7 @@ static void *lib80211_tkip_init(int key_idx)
priv->key_idx = key_idx;
priv->tx_tfm_arc4 = crypto_alloc_skcipher("ecb(arc4)", 0,
CRYPTO_ALG_ASYNC);
priv->tx_tfm_arc4 = crypto_alloc_cipher("arc4", 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(priv->tx_tfm_arc4)) {
priv->tx_tfm_arc4 = NULL;
goto fail;
@ -112,8 +111,7 @@ static void *lib80211_tkip_init(int key_idx)
goto fail;
}
priv->rx_tfm_arc4 = crypto_alloc_skcipher("ecb(arc4)", 0,
CRYPTO_ALG_ASYNC);
priv->rx_tfm_arc4 = crypto_alloc_cipher("arc4", 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(priv->rx_tfm_arc4)) {
priv->rx_tfm_arc4 = NULL;
goto fail;
@ -130,9 +128,9 @@ static void *lib80211_tkip_init(int key_idx)
fail:
if (priv) {
crypto_free_shash(priv->tx_tfm_michael);
crypto_free_skcipher(priv->tx_tfm_arc4);
crypto_free_cipher(priv->tx_tfm_arc4);
crypto_free_shash(priv->rx_tfm_michael);
crypto_free_skcipher(priv->rx_tfm_arc4);
crypto_free_cipher(priv->rx_tfm_arc4);
kfree(priv);
}
@ -144,9 +142,9 @@ static void lib80211_tkip_deinit(void *priv)
struct lib80211_tkip_data *_priv = priv;
if (_priv) {
crypto_free_shash(_priv->tx_tfm_michael);
crypto_free_skcipher(_priv->tx_tfm_arc4);
crypto_free_cipher(_priv->tx_tfm_arc4);
crypto_free_shash(_priv->rx_tfm_michael);
crypto_free_skcipher(_priv->rx_tfm_arc4);
crypto_free_cipher(_priv->rx_tfm_arc4);
}
kfree(priv);
}
@ -344,12 +342,10 @@ static int lib80211_tkip_hdr(struct sk_buff *skb, int hdr_len,
static int lib80211_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
{
struct lib80211_tkip_data *tkey = priv;
SKCIPHER_REQUEST_ON_STACK(req, tkey->tx_tfm_arc4);
int len;
u8 rc4key[16], *pos, *icv;
u32 crc;
struct scatterlist sg;
int err;
int i;
if (tkey->flags & IEEE80211_CRYPTO_TKIP_COUNTERMEASURES) {
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
@ -374,14 +370,10 @@ static int lib80211_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
icv[2] = crc >> 16;
icv[3] = crc >> 24;
crypto_skcipher_setkey(tkey->tx_tfm_arc4, rc4key, 16);
sg_init_one(&sg, pos, len + 4);
skcipher_request_set_tfm(req, tkey->tx_tfm_arc4);
skcipher_request_set_callback(req, 0, NULL, NULL);
skcipher_request_set_crypt(req, &sg, &sg, len + 4, NULL);
err = crypto_skcipher_encrypt(req);
skcipher_request_zero(req);
return err;
crypto_cipher_setkey(tkey->tx_tfm_arc4, rc4key, 16);
for (i = 0; i < len + 4; i++)
crypto_cipher_encrypt_one(tkey->tx_tfm_arc4, pos + i, pos + i);
return 0;
}
/*
@ -400,7 +392,6 @@ static inline int tkip_replay_check(u32 iv32_n, u16 iv16_n,
static int lib80211_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
{
struct lib80211_tkip_data *tkey = priv;
SKCIPHER_REQUEST_ON_STACK(req, tkey->rx_tfm_arc4);
u8 rc4key[16];
u8 keyidx, *pos;
u32 iv32;
@ -408,9 +399,8 @@ static int lib80211_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
struct ieee80211_hdr *hdr;
u8 icv[4];
u32 crc;
struct scatterlist sg;
int plen;
int err;
int i;
hdr = (struct ieee80211_hdr *)skb->data;
@ -463,18 +453,9 @@ static int lib80211_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
plen = skb->len - hdr_len - 12;
crypto_skcipher_setkey(tkey->rx_tfm_arc4, rc4key, 16);
sg_init_one(&sg, pos, plen + 4);
skcipher_request_set_tfm(req, tkey->rx_tfm_arc4);
skcipher_request_set_callback(req, 0, NULL, NULL);
skcipher_request_set_crypt(req, &sg, &sg, plen + 4, NULL);
err = crypto_skcipher_decrypt(req);
skcipher_request_zero(req);
if (err) {
net_dbg_ratelimited("TKIP: failed to decrypt received packet from %pM\n",
hdr->addr2);
return -7;
}
crypto_cipher_setkey(tkey->rx_tfm_arc4, rc4key, 16);
for (i = 0; i < plen + 4; i++)
crypto_cipher_decrypt_one(tkey->rx_tfm_arc4, pos + i, pos + i);
crc = ~crc32_le(~0, pos, plen);
icv[0] = crc;
@ -660,9 +641,9 @@ static int lib80211_tkip_set_key(void *key, int len, u8 * seq, void *priv)
struct lib80211_tkip_data *tkey = priv;
int keyidx;
struct crypto_shash *tfm = tkey->tx_tfm_michael;
struct crypto_skcipher *tfm2 = tkey->tx_tfm_arc4;
struct crypto_cipher *tfm2 = tkey->tx_tfm_arc4;
struct crypto_shash *tfm3 = tkey->rx_tfm_michael;
struct crypto_skcipher *tfm4 = tkey->rx_tfm_arc4;
struct crypto_cipher *tfm4 = tkey->rx_tfm_arc4;
keyidx = tkey->key_idx;
memset(tkey, 0, sizeof(*tkey));

View File

@ -22,7 +22,7 @@
#include <net/lib80211.h>
#include <crypto/skcipher.h>
#include <linux/crypto.h>
#include <linux/crc32.h>
MODULE_AUTHOR("Jouni Malinen");
@ -35,8 +35,8 @@ struct lib80211_wep_data {
u8 key[WEP_KEY_LEN + 1];
u8 key_len;
u8 key_idx;
struct crypto_skcipher *tx_tfm;
struct crypto_skcipher *rx_tfm;
struct crypto_cipher *tx_tfm;
struct crypto_cipher *rx_tfm;
};
static void *lib80211_wep_init(int keyidx)
@ -48,13 +48,13 @@ static void *lib80211_wep_init(int keyidx)
goto fail;
priv->key_idx = keyidx;
priv->tx_tfm = crypto_alloc_skcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC);
priv->tx_tfm = crypto_alloc_cipher("arc4", 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(priv->tx_tfm)) {
priv->tx_tfm = NULL;
goto fail;
}
priv->rx_tfm = crypto_alloc_skcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC);
priv->rx_tfm = crypto_alloc_cipher("arc4", 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(priv->rx_tfm)) {
priv->rx_tfm = NULL;
goto fail;
@ -66,8 +66,8 @@ static void *lib80211_wep_init(int keyidx)
fail:
if (priv) {
crypto_free_skcipher(priv->tx_tfm);
crypto_free_skcipher(priv->rx_tfm);
crypto_free_cipher(priv->tx_tfm);
crypto_free_cipher(priv->rx_tfm);
kfree(priv);
}
return NULL;
@ -77,8 +77,8 @@ static void lib80211_wep_deinit(void *priv)
{
struct lib80211_wep_data *_priv = priv;
if (_priv) {
crypto_free_skcipher(_priv->tx_tfm);
crypto_free_skcipher(_priv->rx_tfm);
crypto_free_cipher(_priv->tx_tfm);
crypto_free_cipher(_priv->rx_tfm);
}
kfree(priv);
}
@ -129,12 +129,10 @@ static int lib80211_wep_build_iv(struct sk_buff *skb, int hdr_len,
static int lib80211_wep_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
{
struct lib80211_wep_data *wep = priv;
SKCIPHER_REQUEST_ON_STACK(req, wep->tx_tfm);
u32 crc, klen, len;
u8 *pos, *icv;
struct scatterlist sg;
u8 key[WEP_KEY_LEN + 3];
int err;
int i;
/* other checks are in lib80211_wep_build_iv */
if (skb_tailroom(skb) < 4)
@ -162,14 +160,12 @@ static int lib80211_wep_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
icv[2] = crc >> 16;
icv[3] = crc >> 24;
crypto_skcipher_setkey(wep->tx_tfm, key, klen);
sg_init_one(&sg, pos, len + 4);
skcipher_request_set_tfm(req, wep->tx_tfm);
skcipher_request_set_callback(req, 0, NULL, NULL);
skcipher_request_set_crypt(req, &sg, &sg, len + 4, NULL);
err = crypto_skcipher_encrypt(req);
skcipher_request_zero(req);
return err;
crypto_cipher_setkey(wep->tx_tfm, key, klen);
for (i = 0; i < len + 4; i++)
crypto_cipher_encrypt_one(wep->tx_tfm, pos + i, pos + i);
return 0;
}
/* Perform WEP decryption on given buffer. Buffer includes whole WEP part of
@ -182,12 +178,10 @@ static int lib80211_wep_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
static int lib80211_wep_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
{
struct lib80211_wep_data *wep = priv;
SKCIPHER_REQUEST_ON_STACK(req, wep->rx_tfm);
u32 crc, klen, plen;
u8 key[WEP_KEY_LEN + 3];
u8 keyidx, *pos, icv[4];
struct scatterlist sg;
int err;
int i;
if (skb->len < hdr_len + 8)
return -1;
@ -208,15 +202,9 @@ static int lib80211_wep_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
/* Apply RC4 to data and compute CRC32 over decrypted data */
plen = skb->len - hdr_len - 8;
crypto_skcipher_setkey(wep->rx_tfm, key, klen);
sg_init_one(&sg, pos, plen + 4);
skcipher_request_set_tfm(req, wep->rx_tfm);
skcipher_request_set_callback(req, 0, NULL, NULL);
skcipher_request_set_crypt(req, &sg, &sg, plen + 4, NULL);
err = crypto_skcipher_decrypt(req);
skcipher_request_zero(req);
if (err)
return -7;
crypto_cipher_setkey(wep->rx_tfm, key, klen);
for (i = 0; i < plen + 4; i++)
crypto_cipher_decrypt_one(wep->rx_tfm, pos + i, pos + i);
crc = ~crc32_le(~0, pos, plen);
icv[0] = crc;