diff options
Diffstat (limited to 'drivers/net/wireless/hostap/hostap_crypt_wep.c')
| -rw-r--r-- | drivers/net/wireless/hostap/hostap_crypt_wep.c | 283 |
1 files changed, 0 insertions, 283 deletions
diff --git a/drivers/net/wireless/hostap/hostap_crypt_wep.c b/drivers/net/wireless/hostap/hostap_crypt_wep.c deleted file mode 100644 index 66c403f..0000000 --- a/drivers/net/wireless/hostap/hostap_crypt_wep.c +++ /dev/null @@ -1,283 +0,0 @@ -/* - * Host AP crypt: host-based WEP encryption implementation for Host AP driver - * - * Copyright (c) 2002-2004, Jouni Malinen <jkmaline@cc.hut.fi> - * - * 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. See README and COPYING for - * more details. - */ - -#include <linux/config.h> -#include <linux/version.h> -#include <linux/module.h> -#include <linux/init.h> -#include <linux/slab.h> -#include <linux/random.h> -#include <linux/skbuff.h> -#include <asm/string.h> - -#include "hostap_crypt.h" -#include "hostap_config.h" - -#ifndef CONFIG_CRYPTO -#error CONFIG_CRYPTO is required to build this module. -#endif -#include <linux/crypto.h> -#include <asm/scatterlist.h> -#include <linux/crc32.h> - -MODULE_AUTHOR("Jouni Malinen"); -MODULE_DESCRIPTION("Host AP crypt: WEP"); -MODULE_LICENSE("GPL"); -MODULE_VERSION(PRISM2_VERSION); - - -struct prism2_wep_data { - u32 iv; -#define WEP_KEY_LEN 13 - u8 key[WEP_KEY_LEN + 1]; - u8 key_len; - u8 key_idx; - struct crypto_tfm *tfm; -}; - - -static void * prism2_wep_init(int keyidx) -{ - struct prism2_wep_data *priv; - - if (!try_module_get(THIS_MODULE)) - return NULL; - - priv = (struct prism2_wep_data *) kmalloc(sizeof(*priv), GFP_ATOMIC); - if (priv == NULL) - goto fail; - memset(priv, 0, sizeof(*priv)); - priv->key_idx = keyidx; - - priv->tfm = crypto_alloc_tfm("arc4", 0); - if (priv->tfm == NULL) { - printk(KERN_DEBUG "hostap_crypt_wep: could not allocate " - "crypto API arc4\n"); - goto fail; - } - - /* start WEP IV from a random value */ - get_random_bytes(&priv->iv, 4); - - return priv; - -fail: - if (priv) { - if (priv->tfm) - crypto_free_tfm(priv->tfm); - kfree(priv); - } - module_put(THIS_MODULE); - return NULL; -} - - -static void prism2_wep_deinit(void *priv) -{ - struct prism2_wep_data *_priv = priv; - if (_priv && _priv->tfm) - crypto_free_tfm(_priv->tfm); - kfree(priv); - module_put(THIS_MODULE); -} - - -/* Perform WEP encryption on given skb that has at least 4 bytes of headroom - * for IV and 4 bytes of tailroom for ICV. 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)) - */ -static int prism2_wep_encrypt(struct sk_buff *skb, int hdr_len, void *priv) -{ - struct prism2_wep_data *wep = priv; - u32 crc, klen, len; - u8 key[WEP_KEY_LEN + 3]; - u8 *pos, *icv; - struct scatterlist sg; - - if (skb_headroom(skb) < 4 || skb_tailroom(skb) < 4 || - skb->len < hdr_len) - return -1; - - len = skb->len - hdr_len; - pos = skb_push(skb, 4); - memmove(pos, pos + 4, hdr_len); - pos += hdr_len; - - klen = 3 + wep->key_len; - - wep->iv++; - - /* 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 ((wep->iv & 0xff00) == 0xff00) { - u8 B = (wep->iv >> 16) & 0xff; - if (B >= 3 && B < klen) - wep->iv += 0x0100; - } - - /* Prepend 24-bit IV to RC4 key and TX frame */ - *pos++ = key[0] = (wep->iv >> 16) & 0xff; - *pos++ = key[1] = (wep->iv >> 8) & 0xff; - *pos++ = key[2] = wep->iv & 0xff; - *pos++ = wep->key_idx << 6; - - /* Copy rest of the WEP key (the secret part) */ - memcpy(key + 3, wep->key, wep->key_len); - - /* Append little-endian CRC32 and encrypt it to produce ICV */ - crc = ~crc32_le(~0, pos, len); - icv = skb_put(skb, 4); - icv[0] = crc; - icv[1] = crc >> 8; - icv[2] = crc >> 16; - icv[3] = crc >> 24; - - crypto_cipher_setkey(wep->tfm, key, klen); - sg.page = virt_to_page(pos); - sg.offset = offset_in_page(pos); - sg.length = len + 4; - crypto_cipher_encrypt(wep->tfm, &sg, &sg, len + 4); - - return 0; -} - - -/* Perform WEP decryption on given buffer. Buffer includes whole WEP part of - * the frame: IV (4 bytes), encrypted payload (including SNAP header), - * ICV (4 bytes). 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. - */ -static int prism2_wep_decrypt(struct sk_buff *skb, int hdr_len, void *priv) -{ - struct prism2_wep_data *wep = priv; - u32 crc, klen, plen; - u8 key[WEP_KEY_LEN + 3]; - u8 keyidx, *pos, icv[4]; - struct scatterlist sg; - - if (skb->len < hdr_len + 8) - return -1; - - pos = skb->data + hdr_len; - key[0] = *pos++; - key[1] = *pos++; - key[2] = *pos++; - keyidx = *pos++ >> 6; - if (keyidx != wep->key_idx) - return -1; - - klen = 3 + wep->key_len; - - /* Copy rest of the WEP key (the secret part) */ - memcpy(key + 3, wep->key, wep->key_len); - - /* Apply RC4 to data and compute CRC32 over decrypted data */ - plen = skb->len - hdr_len - 8; - - crypto_cipher_setkey(wep->tfm, key, klen); - sg.page = virt_to_page(pos); - sg.offset = offset_in_page(pos); - sg.length = plen + 4; - crypto_cipher_decrypt(wep->tfm, &sg, &sg, plen + 4); - - crc = ~crc32_le(~0, pos, plen); - icv[0] = crc; - icv[1] = crc >> 8; - icv[2] = crc >> 16; - icv[3] = crc >> 24; - if (memcmp(icv, pos + plen, 4) != 0) { - /* ICV mismatch - drop frame */ - return -2; - } - - /* Remove IV and ICV */ - memmove(skb->data + 4, skb->data, hdr_len); - skb_pull(skb, 4); - skb_trim(skb, skb->len - 4); - - return 0; -} - - -static int prism2_wep_set_key(void *key, int len, u8 *seq, void *priv) -{ - struct prism2_wep_data *wep = priv; - - if (len < 0 || len > WEP_KEY_LEN) - return -1; - - memcpy(wep->key, key, len); - wep->key_len = len; - - return 0; -} - - -static int prism2_wep_get_key(void *key, int len, u8 *seq, void *priv) -{ - struct prism2_wep_data *wep = priv; - - if (len < wep->key_len) - return -1; - - memcpy(key, wep->key, wep->key_len); - - return wep->key_len; -} - - -static char * prism2_wep_print_stats(char *p, void *priv) -{ - struct prism2_wep_data *wep = priv; - p += sprintf(p, "key[%d] alg=WEP len=%d\n", - wep->key_idx, wep->key_len); - return p; -} - - -static struct hostap_crypto_ops hostap_crypt_wep = { - .name = "WEP", - .init = prism2_wep_init, - .deinit = prism2_wep_deinit, - .encrypt_mpdu = prism2_wep_encrypt, - .decrypt_mpdu = prism2_wep_decrypt, - .encrypt_msdu = NULL, - .decrypt_msdu = NULL, - .set_key = prism2_wep_set_key, - .get_key = prism2_wep_get_key, - .print_stats = prism2_wep_print_stats, - .extra_prefix_len = 4 /* IV */, - .extra_postfix_len = 4 /* ICV */ -}; - - -static int __init hostap_crypto_wep_init(void) -{ - if (hostap_register_crypto_ops(&hostap_crypt_wep) < 0) - return -1; - - return 0; -} - - -static void __exit hostap_crypto_wep_exit(void) -{ - hostap_unregister_crypto_ops(&hostap_crypt_wep); -} - - -module_init(hostap_crypto_wep_init); -module_exit(hostap_crypto_wep_exit); |