diff options
author | John W. Linville <linville@tuxdriver.com> | 2008-10-29 11:35:05 -0400 |
---|---|---|
committer | John W. Linville <linville@tuxdriver.com> | 2008-11-21 11:08:17 -0500 |
commit | 274bfb8dc5ffa16cb073801bebe76ab7f4e2e73d (patch) | |
tree | 04cd3f6a062496911b56737daa6a0858b769ccd6 /net/wireless | |
parent | dfe1bafdbac1c7b48b636fb7ace799e78170e0d6 (diff) | |
download | linux-274bfb8dc5ffa16cb073801bebe76ab7f4e2e73d.tar.gz linux-274bfb8dc5ffa16cb073801bebe76ab7f4e2e73d.tar.bz2 linux-274bfb8dc5ffa16cb073801bebe76ab7f4e2e73d.zip |
lib80211: absorb crypto bits from net/ieee80211
These bits are shared already between ipw2x00 and hostap, and could
probably be shared both more cleanly and with other drivers. This
commit simply relocates the code to lib80211 and adjusts the drivers
appropriately.
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'net/wireless')
-rw-r--r-- | net/wireless/Kconfig | 9 | ||||
-rw-r--r-- | net/wireless/Makefile | 3 | ||||
-rw-r--r-- | net/wireless/lib80211.c | 191 | ||||
-rw-r--r-- | net/wireless/lib80211_crypt_ccmp.c | 492 | ||||
-rw-r--r-- | net/wireless/lib80211_crypt_tkip.c | 784 | ||||
-rw-r--r-- | net/wireless/lib80211_crypt_wep.c | 296 |
6 files changed, 1770 insertions, 5 deletions
diff --git a/net/wireless/Kconfig b/net/wireless/Kconfig index ae7f2262dfb5..f7c64dbe86cc 100644 --- a/net/wireless/Kconfig +++ b/net/wireless/Kconfig @@ -82,3 +82,12 @@ config LIB80211 Drivers should select this themselves if needed. Say Y if you want this built into your kernel. + +config LIB80211_CRYPT_WEP + tristate + +config LIB80211_CRYPT_CCMP + tristate + +config LIB80211_CRYPT_TKIP + tristate diff --git a/net/wireless/Makefile b/net/wireless/Makefile index d2d848d445f2..cc547edb111f 100644 --- a/net/wireless/Makefile +++ b/net/wireless/Makefile @@ -1,6 +1,9 @@ obj-$(CONFIG_WIRELESS_EXT) += wext.o obj-$(CONFIG_CFG80211) += cfg80211.o obj-$(CONFIG_LIB80211) += lib80211.o +obj-$(CONFIG_LIB80211_CRYPT_WEP) += lib80211_crypt_wep.o +obj-$(CONFIG_LIB80211_CRYPT_CCMP) += lib80211_crypt_ccmp.o +obj-$(CONFIG_LIB80211_CRYPT_TKIP) += lib80211_crypt_tkip.o cfg80211-y += core.o sysfs.o radiotap.o util.o reg.o cfg80211-$(CONFIG_NL80211) += nl80211.o diff --git a/net/wireless/lib80211.c b/net/wireless/lib80211.c index e71f7d085621..d681721f4acb 100644 --- a/net/wireless/lib80211.c +++ b/net/wireless/lib80211.c @@ -3,11 +3,23 @@ * * Copyright(c) 2008 John W. Linville <linville@tuxdriver.com> * + * Portions copied from old ieee80211 component, w/ original copyright + * notices below: + * + * Host AP crypto routines + * + * Copyright (c) 2002-2003, Jouni Malinen <j@w1.fi> + * Portions Copyright (C) 2004, Intel Corporation <jketreno@linux.intel.com> + * */ #include <linux/module.h> #include <linux/ctype.h> #include <linux/ieee80211.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/string.h> #include <net/lib80211.h> @@ -19,6 +31,14 @@ MODULE_DESCRIPTION(DRV_DESCRIPTION); MODULE_AUTHOR("John W. Linville <linville@tuxdriver.com>"); MODULE_LICENSE("GPL"); +struct lib80211_crypto_alg { + struct list_head list; + struct lib80211_crypto_ops *ops; +}; + +static LIST_HEAD(lib80211_crypto_algs); +static DEFINE_SPINLOCK(lib80211_crypto_lock); + const char *print_ssid(char *buf, const char *ssid, u8 ssid_len) { const char *s = ssid; @@ -51,15 +71,176 @@ const char *print_ssid(char *buf, const char *ssid, u8 ssid_len) } EXPORT_SYMBOL(print_ssid); -static int __init ieee80211_init(void) +void lib80211_crypt_deinit_entries(struct lib80211_crypt_info *info, int force) { - printk(KERN_INFO DRV_NAME ": " DRV_DESCRIPTION "\n"); + struct lib80211_crypt_data *entry, *next; + unsigned long flags; + + spin_lock_irqsave(info->lock, flags); + list_for_each_entry_safe(entry, next, &info->crypt_deinit_list, list) { + if (atomic_read(&entry->refcnt) != 0 && !force) + continue; + + list_del(&entry->list); + + if (entry->ops) { + entry->ops->deinit(entry->priv); + module_put(entry->ops->owner); + } + kfree(entry); + } + spin_unlock_irqrestore(info->lock, flags); +} +EXPORT_SYMBOL(lib80211_crypt_deinit_entries); + +/* After this, crypt_deinit_list won't accept new members */ +void lib80211_crypt_quiescing(struct lib80211_crypt_info *info) +{ + unsigned long flags; + + spin_lock_irqsave(info->lock, flags); + info->crypt_quiesced = 1; + spin_unlock_irqrestore(info->lock, flags); +} +EXPORT_SYMBOL(lib80211_crypt_quiescing); + +void lib80211_crypt_deinit_handler(unsigned long data) +{ + struct lib80211_crypt_info *info = (struct lib80211_crypt_info *)data; + unsigned long flags; + + lib80211_crypt_deinit_entries(info, 0); + + spin_lock_irqsave(info->lock, flags); + if (!list_empty(&info->crypt_deinit_list) && !info->crypt_quiesced) { + printk(KERN_DEBUG "%s: entries remaining in delayed crypt " + "deletion list\n", info->name); + info->crypt_deinit_timer.expires = jiffies + HZ; + add_timer(&info->crypt_deinit_timer); + } + spin_unlock_irqrestore(info->lock, flags); +} +EXPORT_SYMBOL(lib80211_crypt_deinit_handler); + +void lib80211_crypt_delayed_deinit(struct lib80211_crypt_info *info, + struct lib80211_crypt_data **crypt) +{ + struct lib80211_crypt_data *tmp; + unsigned long flags; + + if (*crypt == NULL) + return; + + tmp = *crypt; + *crypt = NULL; + + /* must not run ops->deinit() while there may be pending encrypt or + * decrypt operations. Use a list of delayed deinits to avoid needing + * locking. */ + + spin_lock_irqsave(info->lock, flags); + if (!info->crypt_quiesced) { + list_add(&tmp->list, &info->crypt_deinit_list); + if (!timer_pending(&info->crypt_deinit_timer)) { + info->crypt_deinit_timer.expires = jiffies + HZ; + add_timer(&info->crypt_deinit_timer); + } + } + spin_unlock_irqrestore(info->lock, flags); +} +EXPORT_SYMBOL(lib80211_crypt_delayed_deinit); + +int lib80211_register_crypto_ops(struct lib80211_crypto_ops *ops) +{ + unsigned long flags; + struct lib80211_crypto_alg *alg; + + alg = kzalloc(sizeof(*alg), GFP_KERNEL); + if (alg == NULL) + return -ENOMEM; + + alg->ops = ops; + + spin_lock_irqsave(&lib80211_crypto_lock, flags); + list_add(&alg->list, &lib80211_crypto_algs); + spin_unlock_irqrestore(&lib80211_crypto_lock, flags); + + printk(KERN_DEBUG "lib80211_crypt: registered algorithm '%s'\n", + ops->name); + + return 0; +} +EXPORT_SYMBOL(lib80211_register_crypto_ops); + +int lib80211_unregister_crypto_ops(struct lib80211_crypto_ops *ops) +{ + struct lib80211_crypto_alg *alg; + unsigned long flags; + + spin_lock_irqsave(&lib80211_crypto_lock, flags); + list_for_each_entry(alg, &lib80211_crypto_algs, list) { + if (alg->ops == ops) + goto found; + } + spin_unlock_irqrestore(&lib80211_crypto_lock, flags); + return -EINVAL; + + found: + printk(KERN_DEBUG "lib80211_crypt: unregistered algorithm " + "'%s'\n", ops->name); + list_del(&alg->list); + spin_unlock_irqrestore(&lib80211_crypto_lock, flags); + kfree(alg); return 0; } +EXPORT_SYMBOL(lib80211_unregister_crypto_ops); + +struct lib80211_crypto_ops *lib80211_get_crypto_ops(const char *name) +{ + struct lib80211_crypto_alg *alg; + unsigned long flags; + + spin_lock_irqsave(&lib80211_crypto_lock, flags); + list_for_each_entry(alg, &lib80211_crypto_algs, list) { + if (strcmp(alg->ops->name, name) == 0) + goto found; + } + spin_unlock_irqrestore(&lib80211_crypto_lock, flags); + return NULL; + + found: + spin_unlock_irqrestore(&lib80211_crypto_lock, flags); + return alg->ops; +} +EXPORT_SYMBOL(lib80211_get_crypto_ops); + +static void *lib80211_crypt_null_init(int keyidx) +{ + return (void *)1; +} + +static void lib80211_crypt_null_deinit(void *priv) +{ +} + +static struct lib80211_crypto_ops lib80211_crypt_null = { + .name = "NULL", + .init = lib80211_crypt_null_init, + .deinit = lib80211_crypt_null_deinit, + .owner = THIS_MODULE, +}; + +static int __init lib80211_init(void) +{ + printk(KERN_INFO DRV_NAME ": " DRV_DESCRIPTION "\n"); + return lib80211_register_crypto_ops(&lib80211_crypt_null); +} -static void __exit ieee80211_exit(void) +static void __exit lib80211_exit(void) { + lib80211_unregister_crypto_ops(&lib80211_crypt_null); + BUG_ON(!list_empty(&lib80211_crypto_algs)); } -module_init(ieee80211_init); -module_exit(ieee80211_exit); +module_init(lib80211_init); +module_exit(lib80211_exit); diff --git a/net/wireless/lib80211_crypt_ccmp.c b/net/wireless/lib80211_crypt_ccmp.c new file mode 100644 index 000000000000..db428194c16a --- /dev/null +++ b/net/wireless/lib80211_crypt_ccmp.c @@ -0,0 +1,492 @@ +/* + * lib80211 crypt: host-based CCMP encryption implementation for lib80211 + * + * Copyright (c) 2003-2004, Jouni Malinen <j@w1.fi> + * Copyright (c) 2008, John W. Linville <linville@tuxdriver.com> + * + * 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/kernel.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/random.h> +#include <linux/skbuff.h> +#include <linux/netdevice.h> +#include <linux/if_ether.h> +#include <linux/if_arp.h> +#include <asm/string.h> +#include <linux/wireless.h> + +#include <linux/ieee80211.h> + +#include <linux/crypto.h> + +#include <net/lib80211.h> + +MODULE_AUTHOR("Jouni Malinen"); +MODULE_DESCRIPTION("Host AP crypt: CCMP"); +MODULE_LICENSE("GPL"); + +#define AES_BLOCK_LEN 16 +#define CCMP_HDR_LEN 8 +#define CCMP_MIC_LEN 8 +#define CCMP_TK_LEN 16 +#define CCMP_PN_LEN 6 + +struct lib80211_ccmp_data { + u8 key[CCMP_TK_LEN]; + int key_set; + + u8 tx_pn[CCMP_PN_LEN]; + u8 rx_pn[CCMP_PN_LEN]; + + u32 dot11RSNAStatsCCMPFormatErrors; + u32 dot11RSNAStatsCCMPReplays; + u32 dot11RSNAStatsCCMPDecryptErrors; + + int key_idx; + + struct crypto_cipher *tfm; + + /* scratch buffers for virt_to_page() (crypto API) */ + u8 tx_b0[AES_BLOCK_LEN], tx_b[AES_BLOCK_LEN], + tx_e[AES_BLOCK_LEN], tx_s0[AES_BLOCK_LEN]; + u8 rx_b0[AES_BLOCK_LEN], rx_b[AES_BLOCK_LEN], rx_a[AES_BLOCK_LEN]; +}; + +static inline void lib80211_ccmp_aes_encrypt(struct crypto_cipher *tfm, + const u8 pt[16], u8 ct[16]) +{ + crypto_cipher_encrypt_one(tfm, ct, pt); +} + +static void *lib80211_ccmp_init(int key_idx) +{ + struct lib80211_ccmp_data *priv; + + priv = kzalloc(sizeof(*priv), GFP_ATOMIC); + if (priv == NULL) + goto fail; + priv->key_idx = key_idx; + + priv->tfm = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC); + if (IS_ERR(priv->tfm)) { + printk(KERN_DEBUG "lib80211_crypt_ccmp: could not allocate " + "crypto API aes\n"); + priv->tfm = NULL; + goto fail; + } + + return priv; + + fail: + if (priv) { + if (priv->tfm) + crypto_free_cipher(priv->tfm); + kfree(priv); + } + + return NULL; +} + +static void lib80211_ccmp_deinit(void *priv) +{ + struct lib80211_ccmp_data *_priv = priv; + if (_priv && _priv->tfm) + crypto_free_cipher(_priv->tfm); + kfree(priv); +} + +static inline void xor_block(u8 * b, u8 * a, size_t len) +{ + int i; + for (i = 0; i < len; i++) + b[i] ^= a[i]; +} + +static void ccmp_init_blocks(struct crypto_cipher *tfm, + struct ieee80211_hdr *hdr, + u8 * pn, size_t dlen, u8 * b0, u8 * auth, u8 * s0) +{ + u8 *pos, qc = 0; + size_t aad_len; + int a4_included, qc_included; + u8 aad[2 * AES_BLOCK_LEN]; + + a4_included = ieee80211_has_a4(hdr->frame_control); + qc_included = ieee80211_is_data_qos(hdr->frame_control); + + aad_len = 22; + if (a4_included) + aad_len += 6; + if (qc_included) { + pos = (u8 *) & hdr->addr4; + if (a4_included) + pos += 6; + qc = *pos & 0x0f; + aad_len += 2; + } + + /* CCM Initial Block: + * Flag (Include authentication header, M=3 (8-octet MIC), + * L=1 (2-octet Dlen)) + * Nonce: 0x00 | A2 | PN + * Dlen */ + b0[0] = 0x59; + b0[1] = qc; + memcpy(b0 + 2, hdr->addr2, ETH_ALEN); + memcpy(b0 + 8, pn, CCMP_PN_LEN); + b0[14] = (dlen >> 8) & 0xff; + b0[15] = dlen & 0xff; + + /* AAD: + * FC with bits 4..6 and 11..13 masked to zero; 14 is always one + * A1 | A2 | A3 + * SC with bits 4..15 (seq#) masked to zero + * A4 (if present) + * QC (if present) + */ + pos = (u8 *) hdr; + aad[0] = 0; /* aad_len >> 8 */ + aad[1] = aad_len & 0xff; + aad[2] = pos[0] & 0x8f; + aad[3] = pos[1] & 0xc7; + memcpy(aad + 4, hdr->addr1, 3 * ETH_ALEN); + pos = (u8 *) & hdr->seq_ctrl; + aad[22] = pos[0] & 0x0f; + aad[23] = 0; /* all bits masked */ + memset(aad + 24, 0, 8); + if (a4_included) + memcpy(aad + 24, hdr->addr4, ETH_ALEN); + if (qc_included) { + aad[a4_included ? 30 : 24] = qc; + /* rest of QC masked */ + } + + /* Start with the first block and AAD */ + lib80211_ccmp_aes_encrypt(tfm, b0, auth); + xor_block(auth, aad, AES_BLOCK_LEN); + lib80211_ccmp_aes_encrypt(tfm, auth, auth); + xor_block(auth, &aad[AES_BLOCK_LEN], AES_BLOCK_LEN); + lib80211_ccmp_aes_encrypt(tfm, auth, auth); + b0[0] &= 0x07; + b0[14] = b0[15] = 0; + lib80211_ccmp_aes_encrypt(tfm, b0, s0); +} + +static int lib80211_ccmp_hdr(struct sk_buff *skb, int hdr_len, + u8 *aeskey, int keylen, void *priv) +{ + struct lib80211_ccmp_data *key = priv; + int i; + u8 *pos; + + if (skb_headroom(skb) < CCMP_HDR_LEN || skb->len < hdr_len) + return -1; + + if (aeskey != NULL && keylen >= CCMP_TK_LEN) + memcpy(aeskey, key->key, CCMP_TK_LEN); + + pos = skb_push(skb, CCMP_HDR_LEN); + memmove(pos, pos + CCMP_HDR_LEN, hdr_len); + pos += hdr_len; + + i = CCMP_PN_LEN - 1; + while (i >= 0) { + key->tx_pn[i]++; + if (key->tx_pn[i] != 0) + break; + i--; + } + + *pos++ = key->tx_pn[5]; + *pos++ = key->tx_pn[4]; + *pos++ = 0; + *pos++ = (key->key_idx << 6) | (1 << 5) /* Ext IV included */ ; + *pos++ = key->tx_pn[3]; + *pos++ = key->tx_pn[2]; + *pos++ = key->tx_pn[1]; + *pos++ = key->tx_pn[0]; + + return CCMP_HDR_LEN; +} + +static int lib80211_ccmp_encrypt(struct sk_buff *skb, int hdr_len, void *priv) +{ + struct lib80211_ccmp_data *key = priv; + int data_len, i, blocks, last, len; + u8 *pos, *mic; + struct ieee80211_hdr *hdr; + u8 *b0 = key->tx_b0; + u8 *b = key->tx_b; + u8 *e = key->tx_e; + u8 *s0 = key->tx_s0; + + if (skb_tailroom(skb) < CCMP_MIC_LEN || skb->len < hdr_len) + return -1; + + data_len = skb->len - hdr_len; + len = lib80211_ccmp_hdr(skb, hdr_len, NULL, 0, priv); + if (len < 0) + return -1; + + pos = skb->data + hdr_len + CCMP_HDR_LEN; + mic = skb_put(skb, CCMP_MIC_LEN); + hdr = (struct ieee80211_hdr *)skb->data; + ccmp_init_blocks(key->tfm, hdr, key->tx_pn, data_len, b0, b, s0); + + blocks = DIV_ROUND_UP(data_len, AES_BLOCK_LEN); + last = data_len % AES_BLOCK_LEN; + + for (i = 1; i <= blocks; i++) { + len = (i == blocks && last) ? last : AES_BLOCK_LEN; + /* Authentication */ + xor_block(b, pos, len); + lib80211_ccmp_aes_encrypt(key->tfm, b, b); + /* Encryption, with counter */ + b0[14] = (i >> 8) & 0xff; + b0[15] = i & 0xff; + lib80211_ccmp_aes_encrypt(key->tfm, b0, e); + xor_block(pos, e, len); + pos += len; + } + + for (i = 0; i < CCMP_MIC_LEN; i++) + mic[i] = b[i] ^ s0[i]; + + return 0; +} + +/* + * deal with seq counter wrapping correctly. + * refer to timer_after() for jiffies wrapping handling + */ +static inline int ccmp_replay_check(u8 *pn_n, u8 *pn_o) +{ + u32 iv32_n, iv16_n; + u32 iv32_o, iv16_o; + + iv32_n = (pn_n[0] << 24) | (pn_n[1] << 16) | (pn_n[2] << 8) | pn_n[3]; + iv16_n = (pn_n[4] << 8) | pn_n[5]; + + iv32_o = (pn_o[0] << 24) | (pn_o[1] << 16) | (pn_o[2] << 8) | pn_o[3]; + iv16_o = (pn_o[4] << 8) | pn_o[5]; + + if ((s32)iv32_n - (s32)iv32_o < 0 || + (iv32_n == iv32_o && iv16_n <= iv16_o)) + return 1; + return 0; +} + +static int lib80211_ccmp_decrypt(struct sk_buff *skb, int hdr_len, void *priv) +{ + struct lib80211_ccmp_data *key = priv; + u8 keyidx, *pos; + struct ieee80211_hdr *hdr; + u8 *b0 = key->rx_b0; + u8 *b = key->rx_b; + u8 *a = key->rx_a; + u8 pn[6]; + int i, blocks, last, len; + size_t data_len = skb->len - hdr_len - CCMP_HDR_LEN - CCMP_MIC_LEN; + u8 *mic = skb->data + skb->len - CCMP_MIC_LEN; + + if (skb->len < hdr_len + CCMP_HDR_LEN + CCMP_MIC_LEN) { + key->dot11RSNAStatsCCMPFormatErrors++; + return -1; + } + + hdr = (struct ieee80211_hdr *)skb->data; + pos = skb->data + hdr_len; + keyidx = pos[3]; + if (!(keyidx & (1 << 5))) { + if (net_ratelimit()) { + printk(KERN_DEBUG "CCMP: received packet without ExtIV" + " flag from %pM\n", hdr->addr2); + } + key->dot11RSNAStatsCCMPFormatErrors++; + return -2; + } + keyidx >>= 6; + if (key->key_idx != keyidx) { + printk(KERN_DEBUG "CCMP: RX tkey->key_idx=%d frame " + "keyidx=%d priv=%p\n", key->key_idx, keyidx, priv); + return -6; + } + if (!key->key_set) { + if (net_ratelimit()) { + printk(KERN_DEBUG "CCMP: received packet from %pM" + " with keyid=%d that does not have a configured" + " key\n", hdr->addr2, keyidx); + } + return -3; + } + + pn[0] = pos[7]; + pn[1] = pos[6]; + pn[2] = pos[5]; + pn[3] = pos[4]; + pn[4] = pos[1]; + pn[5] = pos[0]; + pos += 8; + + if (ccmp_replay_check(pn, key->rx_pn)) { + if (net_ratelimit()) { + printk(KERN_DEBUG "CCMP: replay detected: STA=%pM " + "previous PN %02x%02x%02x%02x%02x%02x " + "received PN %02x%02x%02x%02x%02x%02x\n", + hdr->addr2, + key->rx_pn[0], key->rx_pn[1], key->rx_pn[2], + key->rx_pn[3], key->rx_pn[4], key->rx_pn[5], + pn[0], pn[1], pn[2], pn[3], pn[4], pn[5]); + } + key->dot11RSNAStatsCCMPReplays++; + return -4; + } + + ccmp_init_blocks(key->tfm, hdr, pn, data_len, b0, a, b); + xor_block(mic, b, CCMP_MIC_LEN); + + blocks = DIV_ROUND_UP(data_len, AES_BLOCK_LEN); + last = data_len % AES_BLOCK_LEN; + + for (i = 1; i <= blocks; i++) { + len = (i == blocks && last) ? last : AES_BLOCK_LEN; + /* Decrypt, with counter */ + b0[14] = (i >> 8) & 0xff; + b0[15] = i & 0xff; + lib80211_ccmp_aes_encrypt(key->tfm, b0, b); + xor_block(pos, b, len); + /* Authentication */ + xor_block(a, pos, len); + lib80211_ccmp_aes_encrypt(key->tfm, a, a); + pos += len; + } + + if (memcmp(mic, a, CCMP_MIC_LEN) != 0) { + if (net_ratelimit()) { + printk(KERN_DEBUG "CCMP: decrypt failed: STA=" + "%pM\n", hdr->addr2); + } + key->dot11RSNAStatsCCMPDecryptErrors++; + return -5; + } + + memcpy(key->rx_pn, pn, CCMP_PN_LEN); + + /* Remove hdr and MIC */ + memmove(skb->data + CCMP_HDR_LEN, skb->data, hdr_len); + skb_pull(skb, CCMP_HDR_LEN); + skb_trim(skb, skb->len - CCMP_MIC_LEN); + + return keyidx; +} + +static int lib80211_ccmp_set_key(void *key, int len, u8 * seq, void *priv) +{ + struct lib80211_ccmp_data *data = priv; + int keyidx; + struct crypto_cipher *tfm = data->tfm; + + keyidx = data->key_idx; + memset(data, 0, sizeof(*data)); + data->key_idx = keyidx; + data->tfm = tfm; + if (len == CCMP_TK_LEN) { + memcpy(data->key, key, CCMP_TK_LEN); + data->key_set = 1; + if (seq) { + data->rx_pn[0] = seq[5]; + data->rx_pn[1] = seq[4]; + data->rx_pn[2] = seq[3]; + data->rx_pn[3] = seq[2]; + data->rx_pn[4] = seq[1]; + data->rx_pn[5] = seq[0]; + } + crypto_cipher_setkey(data->tfm, data->key, CCMP_TK_LEN); + } else if (len == 0) + data->key_set = 0; + else + return -1; + + return 0; +} + +static int lib80211_ccmp_get_key(void *key, int len, u8 * seq, void *priv) +{ + struct lib80211_ccmp_data *data = priv; + + if (len < CCMP_TK_LEN) + return -1; + + if (!data->key_set) + return 0; + memcpy(key, data->key, CCMP_TK_LEN); + + if (seq) { + seq[0] = data->tx_pn[5]; + seq[1] = data->tx_pn[4]; + seq[2] = data->tx_pn[3]; + seq[3] = data->tx_pn[2]; + seq[4] = data->tx_pn[1]; + seq[5] = data->tx_pn[0]; + } + + return CCMP_TK_LEN; +} + +static char *lib80211_ccmp_print_stats(char *p, void *priv) +{ + struct lib80211_ccmp_data *ccmp = priv; + + p += sprintf(p, "key[%d] alg=CCMP key_set=%d " + "tx_pn=%02x%02x%02x%02x%02x%02x " + "rx_pn=%02x%02x%02x%02x%02x%02x " + "format_errors=%d replays=%d decrypt_errors=%d\n", + ccmp->key_idx, ccmp->key_set, + ccmp->tx_pn[0], ccmp->tx_pn[1], ccmp->tx_pn[2], + ccmp->tx_pn[3], ccmp->tx_pn[4], ccmp->tx_pn[5], + ccmp->rx_pn[0], ccmp->rx_pn[1], ccmp->rx_pn[2], + ccmp->rx_pn[3], ccmp->rx_pn[4], ccmp->rx_pn[5], + ccmp->dot11RSNAStatsCCMPFormatErrors, + ccmp->dot11RSNAStatsCCMPReplays, + ccmp->dot11RSNAStatsCCMPDecryptErrors); + + return p; +} + +static struct lib80211_crypto_ops lib80211_crypt_ccmp = { + .name = "CCMP", + .init = lib80211_ccmp_init, + .deinit = lib80211_ccmp_deinit, + .build_iv = lib80211_ccmp_hdr, + .encrypt_mpdu = lib80211_ccmp_encrypt, + .decrypt_mpdu = lib80211_ccmp_decrypt, + .encrypt_msdu = NULL, + .decrypt_msdu = NULL, + .set_key = lib80211_ccmp_set_key, + .get_key = lib80211_ccmp_get_key, + .print_stats = lib80211_ccmp_print_stats, + .extra_mpdu_prefix_len = CCMP_HDR_LEN, + .extra_mpdu_postfix_len = CCMP_MIC_LEN, + .owner = THIS_MODULE, +}; + +static int __init lib80211_crypto_ccmp_init(void) +{ + return lib80211_register_crypto_ops(&lib80211_crypt_ccmp); +} + +static void __exit lib80211_crypto_ccmp_exit(void) +{ + lib80211_unregister_crypto_ops(&lib80211_crypt_ccmp); +} + +module_init(lib80211_crypto_ccmp_init); +module_exit(lib80211_crypto_ccmp_exit); diff --git a/net/wireless/lib80211_crypt_tkip.c b/net/wireless/lib80211_crypt_tkip.c new file mode 100644 index 000000000000..7e8e22bfed90 --- /dev/null +++ b/net/wireless/lib80211_crypt_tkip.c @@ -0,0 +1,784 @@ +/* + * lib80211 crypt: host-based TKIP encryption implementation for lib80211 + * + * Copyright (c) 2003-2004, Jouni Malinen <j@w1.fi> + * Copyright (c) 2008, John W. Linville <linville@tuxdriver.com> + * + * 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/err.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/random.h> +#include <linux/scatterlist.h> +#include <linux/skbuff.h> +#include <linux/netdevice.h> +#include <linux/mm.h> +#include <linux/if_ether.h> +#include <linux/if_arp.h> +#include <asm/string.h> + +#include <linux/wireless.h> +#include <linux/ieee80211.h> +#include <net/iw_handler.h> + +#include <linux/crypto.h> +#include <linux/crc32.h> + +#include <net/lib80211.h> + +MODULE_AUTHOR("Jouni Malinen"); +MODULE_DESCRIPTION("lib80211 crypt: TKIP"); +MODULE_LICENSE("GPL"); + +struct lib80211_tkip_data { +#define TKIP_KEY_LEN 32 + u8 key[TKIP_KEY_LEN]; + int key_set; + + u32 tx_iv32; + u16 tx_iv16; + u16 tx_ttak[5]; + int tx_phase1_done; + + u32 rx_iv32; + u16 rx_iv16; + u16 rx_ttak[5]; + int rx_phase1_done; + u32 rx_iv32_new; + u16 rx_iv16_new; + + u32 dot11RSNAStatsTKIPReplays; + u32 dot11RSNAStatsTKIPICVErrors; + u32 dot11RSNAStatsTKIPLocalMICFailures; + + int key_idx; + + struct crypto_blkcipher *rx_tfm_arc4; + struct crypto_hash *rx_tfm_michael; + struct crypto_blkcipher *tx_tfm_arc4; + struct crypto_hash *tx_tfm_michael; + + /* scratch buffers for virt_to_page() (crypto API) */ + u8 rx_hdr[16], tx_hdr[16]; + + unsigned long flags; +}; + +static unsigned long lib80211_tkip_set_flags(unsigned long flags, void *priv) +{ + struct lib80211_tkip_data *_priv = priv; + unsigned long old_flags = _priv->flags; + _priv->flags = flags; + return old_flags; +} + +static unsigned long lib80211_tkip_get_flags(void *priv) +{ + struct lib80211_tkip_data *_priv = priv; + return _priv->flags; +} + +static void *lib80211_tkip_init(int key_idx) +{ + struct lib80211_tkip_data *priv; + + priv = kzalloc(sizeof(*priv), GFP_ATOMIC); + if (priv == NULL) + goto fail; + + priv->key_idx = key_idx; + + priv->tx_tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0, + CRYPTO_ALG_ASYNC); + if (IS_ERR(priv->tx_tfm_arc4)) { + printk(KERN_DEBUG "lib80211_crypt_tkip: could not allocate " + "crypto API arc4\n"); + priv->tx_tfm_arc4 = NULL; + goto fail; + } + + priv->tx_tfm_michael = crypto_alloc_hash("michael_mic", 0, + CRYPTO_ALG_ASYNC); + if (IS_ERR(priv->tx_tfm_michael)) { + printk(KERN_DEBUG "lib80211_crypt_tkip: could not allocate " + "crypto API michael_mic\n"); + priv->tx_tfm_michael = NULL; + goto fail; + } + + priv->rx_tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0, + CRYPTO_ALG_ASYNC); + if (IS_ERR(priv->rx_tfm_arc4)) { + printk(KERN_DEBUG "lib80211_crypt_tkip: could not allocate " + "crypto API arc4\n"); + priv->rx_tfm_arc4 = NULL; + goto fail; + } + + priv->rx_tfm_michael = crypto_alloc_hash("michael_mic", 0, + CRYPTO_ALG_ASYNC); + if (IS_ERR(priv->rx_tfm_michael)) { + printk(KERN_DEBUG "lib80211_crypt_tkip: could not allocate " + "crypto API michael_mic\n"); + priv->rx_tfm_michael = NULL; + goto fail; + } + + return priv; + + fail: + if (priv) { + if (priv->tx_tfm_michael) + crypto_free_hash(priv->tx_tfm_michael); + if (priv->tx_tfm_arc4) + crypto_free_blkcipher(priv->tx_tfm_arc4); + if (priv->rx_tfm_michael) + crypto_free_hash(priv->rx_tfm_michael); + if (priv->rx_tfm_arc4) + crypto_free_blkcipher(priv->rx_tfm_arc4); + kfree(priv); + } + + return NULL; +} + +static void lib80211_tkip_deinit(void *priv) +{ + struct lib80211_tkip_data *_priv = priv; + if (_priv) { + if (_priv->tx_tfm_michael) + crypto_free_hash(_priv->tx_tfm_michael); + if (_priv->tx_tfm_arc4) + crypto_free_blkcipher(_priv->tx_tfm_arc4); + if (_priv->rx_tfm_michael) + crypto_free_hash(_priv->rx_tfm_michael); + if (_priv->rx_tfm_arc4) + crypto_free_blkcipher(_priv->rx_tfm_arc4); + } + kfree(priv); +} + +static inline u16 RotR1(u16 val) +{ + return (val >> 1) | (val << 15); +} + +static inline u8 Lo8(u16 val) +{ + return val & 0xff; +} + +static inline u8 Hi8(u16 val) +{ + return val >> 8; +} + +static inline u16 Lo16(u32 val) +{ + return val & 0xffff; +} + +static inline u16 Hi16(u32 val) +{ + return val >> 16; +} + +static inline u16 Mk16(u8 hi, u8 lo) +{ + return lo | (((u16) hi) << 8); +} + +static inline u16 Mk16_le(__le16 * v) +{ + return le16_to_cpu(*v); +} + +static const u16 Sbox[256] = { + 0xC6A5, 0xF884, 0xEE99, 0xF68D, 0xFF0D, 0xD6BD, 0xDEB1, 0x9154, + 0x6050, 0x0203, 0xCEA9, 0x567D, 0xE719, 0xB562, 0x4DE6, 0xEC9A, + 0x8F45, 0x1F9D, 0x8940, 0xFA87, 0xEF15, 0xB2EB, 0x8EC9, 0xFB0B, + 0x41EC, 0xB367, 0x5FFD, 0x45EA, 0x23BF, 0x53F7, 0xE496, 0x9B5B, + 0x75C2, 0xE11C, 0x3DAE, 0x4C6A, 0x6C5A, 0x7E41, 0xF502, 0x834F, + 0x685C, 0x51F4, 0xD134, 0xF908, 0xE293, 0xAB73, 0x6253, 0x2A3F, + 0x080C, 0x9552, 0x4665, 0x9D5E, 0x3028, 0x37A1, 0x0A0F, 0x2FB5, + 0x0E09, 0x2436, 0x1B9B, 0xDF3D, 0xCD26, 0x4E69, 0x7FCD, 0xEA9F, + 0x121B, 0x1D9E, 0x5874, 0x342E, 0x362D, 0xDCB2, 0xB4EE, 0x5BFB, + 0xA4F6, 0x764D, 0xB761, 0x7DCE, 0x527B, 0xDD3E, 0x5E71, 0x1397, + 0xA6F5, 0xB968, 0x0000, 0xC12C, 0x4060, 0xE31F, 0x79C8, 0xB6ED, + 0xD4BE, 0x8D46, 0x67D9, 0x724B, 0x94DE, 0x98D4, 0xB0E8, 0x854A, + 0xBB6B, 0xC52A, 0x4FE5, 0xED16, 0x86C5, 0x9AD7, 0x6655, 0x1194, + 0x8ACF, 0xE910, 0x0406, 0xFE81, 0xA0F0, 0x7844, 0x25BA, 0x4BE3, + 0xA2F3, 0x5DFE, 0x80C0, 0x058A, 0x3FAD, 0x21BC, 0x7048, 0xF104, + 0x63DF, 0x77C1, 0xAF75, 0x4263, 0x2030, 0xE51A, 0xFD0E, 0xBF6D, + 0x814C, 0x1814, 0x2635, 0xC32F, 0xBEE1, 0x35A2, 0x88CC, 0x2E39, + 0x9357, 0x55F2, 0xFC82, 0x7A47, 0xC8AC, 0xBAE7, 0x322B, 0xE695, + 0xC0A0, 0x1998, 0x9ED1, 0xA37F, 0x4466, 0x547E, 0x3BAB, 0x0B83, + 0x8CCA, 0xC729, 0x6BD3, 0x283C, 0xA779, 0xBCE2, 0x161D, 0xAD76, + 0xDB3B, 0x6456, 0x744E, 0x141E, 0x92DB, 0x0C0A, 0x486C, 0xB8E4, + 0x9F5D, 0xBD6E, 0x43EF, 0xC4A6, 0x39A8, 0x31A4, 0xD337, 0xF28B, + 0xD532, 0x8B43, 0x6E59, 0xDAB7, 0x018C, 0xB164, 0x9CD2, 0x49E0, + 0xD8B4, 0xACFA, 0xF307, 0xCF25, 0xCAAF, 0xF48E, 0x47E9, 0x1018, + 0x6FD5, 0xF088, 0x4A6F, 0x5C72, 0x3824, 0x57F1, 0x73C7, 0x9751, + 0xCB23, 0xA17C, 0xE89C, 0x3E21, 0x96DD, 0x61DC, 0x0D86, 0x0F85, + 0xE090, 0x7C42, 0x71C4, 0xCCAA, 0x90D8, 0x0605, 0xF701, 0x1C12, + 0xC2A3, 0x6A5F, 0xAEF9, 0x69D0, 0x1791, 0x9958, 0x3A27, 0x27B9, + 0xD938, 0xEB13, 0x2BB3, 0x2233, 0xD2BB, 0xA970, 0x0789, 0x33A7, + 0x2DB6, 0x3C22, 0x1592, 0xC920, 0x8749, 0xAAFF, 0x5078, 0xA57A, + 0x038F, 0x59F8, 0x0980, 0x1A17, 0x65DA, 0xD731, 0x84C6, 0xD0B8, + 0x82C3, 0x29B0, 0x5A77, 0x1E11, 0x7BCB, 0xA8FC, 0x6DD6, 0x2C3A, +}; + +static inline u16 _S_(u16 v) +{ + u16 t = Sbox[Hi8(v)]; + return Sbox[Lo8(v)] ^ ((t << 8) | (t >> 8)); +} + +#define PHASE1_LOOP_COUNT 8 + +static void tkip_mixing_phase1(u16 * TTAK, const u8 * TK, const u8 * TA, + u32 IV32) +{ + int i, j; + + /* Initialize the 80-bit TTAK from TSC (IV32) and TA[0..5] */ + TTAK[0] = Lo16(IV32); + TTAK[1] = Hi16(IV32); + TTAK[2] = Mk16(TA[1], TA[0]); + TTAK[3] = Mk16(TA[3], TA[2]); + TTAK[4] = Mk16(TA[5], TA[4]); + + for (i = 0; i < PHASE1_LOOP_COUNT; i++) { + j = 2 * (i & 1); + TTAK[0] += _S_(TTAK[4] ^ Mk16(TK[1 + j], TK[0 + j])); + TTAK[1] += _S_(TTAK[0] ^ Mk16(TK[5 + j], TK[4 + j])); + TTAK[2] += _S_(TTAK[1] ^ Mk16(TK[9 + j], TK[8 + j])); + TTAK[3] += _S_(TTAK[2] ^ Mk16(TK[13 + j], TK[12 + j])); + TTAK[4] += _S_(TTAK[3] ^ Mk16(TK[1 + j], TK[0 + j])) + i; + } +} + +static void tkip_mixing_phase2(u8 * WEPSeed, const u8 * TK, const u16 * TTAK, + u16 IV16) +{ + /* Make temporary area overlap WEP seed so that the final copy can be + * avoided on little endian hosts. */ + u16 *PPK = (u16 *) & WEPSeed[4]; + + /* Step 1 - make copy of TTAK and bring in TSC */ + PPK[0] = TTAK[0]; + PPK[1] = TTAK[1]; + PPK[2] = TTAK[2]; + PPK[3] = TTAK[3]; + PPK[4] = TTAK[4]; + PPK[5] = TTAK[4] + IV16; + + /* Step 2 - 96-bit bijective mixing using S-box */ + PPK[0] += _S_(PPK[5] ^ Mk16_le((__le16 *) & TK[0])); + PPK[1] += _S_(PPK[0] ^ Mk16_le((__le16 *) & TK[2])); + PPK[2] += _S_(PPK[1] ^ Mk16_le((__le16 *) & TK[4])); + PPK[3] += _S_(PPK[2] ^ Mk16_le((__le16 *) & TK[6])); + PPK[4] += _S_(PPK[3] ^ Mk16_le((__le16 *) & TK[8])); + PPK[5] += _S_(PPK[4] ^ Mk16_le((__le16 *) & TK[10])); + + PPK[0] += RotR1(PPK[5] ^ Mk16_le((__le16 *) & TK[12])); + PPK[1] += RotR1(PPK[0] ^ Mk16_le((__le16 *) & TK[14])); + PPK[2] += RotR1(PPK[1]); + PPK[3] += RotR1(PPK[2]); + PPK[4] += RotR1(PPK[3]); + PPK[5] += RotR1(PPK[4]); + + /* Step 3 - bring in last of TK bits, assign 24-bit WEP IV value + * WEPSeed[0..2] is transmitted as WEP IV */ + WEPSeed[0] = Hi8(IV16); + WEPSeed[1] = (Hi8(IV16) | 0x20) & 0x7F; + WEPSeed[2] = Lo8(IV16); + WEPSeed[3] = Lo8((PPK[5] ^ Mk16_le((__le16 *) & TK[0])) >> 1); + +#ifdef __BIG_ENDIAN + { + int i; + for (i = 0; i < 6; i++) + PPK[i] = (PPK[i] << 8) | (PPK[i] >> 8); + } +#endif +} + +static int lib80211_tkip_hdr(struct sk_buff *skb, int hdr_len, + u8 * rc4key, int keylen, void *priv) +{ + struct lib80211_tkip_data *tkey = priv; + int len; + u8 *pos; + struct ieee80211_hdr *hdr; + + hdr = (struct ieee80211_hdr *)skb->data; + + if (skb_headroom(skb) < 8 || skb->len < hdr_len) + return -1; + + if (rc4key == NULL || keylen < 16) + return -1; + + if (!tkey->tx_phase1_done) { + tkip_mixing_phase1(tkey->tx_ttak, tkey->key, hdr->addr2, + tkey->tx_iv32); + tkey->tx_phase1_done = 1; + } + tkip_mixing_phase2(rc4key, tkey->key, tkey->tx_ttak, tkey->tx_iv16); + + len = skb->len - hdr_len; + pos = skb_push(skb, 8); + memmove(pos, pos + 8, hdr_len); + pos += hdr_len; + + *pos++ = *rc4key; + *pos++ = *(rc4key + 1); + *pos++ = *(rc4key + 2); + *pos++ = (tkey->key_idx << 6) | (1 << 5) /* Ext IV included */ ; + *pos++ = tkey->tx_iv32 & 0xff; + *pos++ = (tkey->tx_iv32 >> 8) & 0xff; + *pos++ = (tkey->tx_iv32 >> 16) & 0xff; + *pos++ = (tkey->tx_iv32 >> 24) & 0xff; + + tkey->tx_iv16++; + if (tkey->tx_iv16 == 0) { + tkey->tx_phase1_done = 0; + tkey->tx_iv32++; + } + + return 8; +} + +static int lib80211_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv) +{ + struct lib80211_tkip_data *tkey = priv; + struct blkcipher_desc desc = { .tfm = tkey->tx_tfm_arc4 }; + int len; + u8 rc4key[16], *pos, *icv; + u32 crc; + struct scatterlist sg; + + if (tkey->flags & IEEE80211_CRYPTO_TKIP_COUNTERMEASURES) { + if (net_ratelimit()) { + struct ieee80211_hdr *hdr = + (struct ieee80211_hdr *)skb->data; + printk(KERN_DEBUG ": TKIP countermeasures: dropped " + "TX packet to %pM\n", hdr->addr1); + } + return -1; + } + + if (skb_tailroom(skb) < 4 || skb->len < hdr_len) + return -1; + + len = skb->len - hdr_len; + pos = skb->data + hdr_len; + + if ((lib80211_tkip_hdr(skb, hdr_len, rc4key, 16, priv)) < 0) + return -1; + + icv = skb_put(skb, 4); + + crc = ~crc32_le(~0, pos, len); + icv[0] = crc; + icv[1] = crc >> 8; + icv[2] = crc >> 16; + icv[3] = crc >> 24; + + crypto_blkcipher_setkey(tkey->tx_tfm_arc4, rc4key, 16); + sg_init_one(&sg, pos, len + 4); + return crypto_blkcipher_encrypt(&desc, &sg, &sg, len + 4); +} + +/* + * deal with seq counter wrapping correctly. + * refer to timer_after() for jiffies wrapping handling + */ +static inline int tkip_replay_check(u32 iv32_n, u16 iv16_n, + u32 iv32_o, u16 iv16_o) +{ + if ((s32)iv32_n - (s32)iv32_o < 0 || + (iv32_n == iv32_o && iv16_n <= iv16_o)) + return 1; + return 0; +} + +static int lib80211_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv) +{ + struct lib80211_tkip_data *tkey = priv; + struct blkcipher_desc desc = { .tfm = tkey->rx_tfm_arc4 }; + u8 rc4key[16]; + u8 keyidx, *pos; + u32 iv32; + u16 iv16; + struct ieee80211_hdr *hdr; + u8 icv[4]; + u32 crc; + struct scatterlist sg; + int plen; + + hdr = (struct ieee80211_hdr *)skb->data; + + if (tkey->flags & IEEE80211_CRYPTO_TKIP_COUNTERMEASURES) { + if (net_ratelimit()) { + printk(KERN_DEBUG ": TKIP countermeasures: dropped " + "received packet from %pM\n", hdr->addr2); + } + return -1; + } + + if (skb->len < hdr_len + 8 + 4) + return -1; + + pos = skb->data + hdr_len; + keyidx = pos[3]; + if (!(keyidx & (1 << 5))) { + if (net_ratelimit()) { + printk(KERN_DEBUG "TKIP: received packet without ExtIV" + " flag from %pM\n", hdr->addr2); + } + return -2; + } + keyidx >>= 6; + if (tkey->key_idx != keyidx) { + printk(KERN_DEBUG "TKIP: RX tkey->key_idx=%d frame " + "keyidx=%d priv=%p\n", tkey->key_idx, keyidx, priv); + return -6; + } + if (!tkey->key_set) { + if (net_ratelimit()) { + printk(KERN_DEBUG "TKIP: received packet from %pM" + " with keyid=%d that does not have a configured" + " key\n", hdr->addr2, keyidx); + } + return -3; + } + iv16 = (pos[0] << 8) | pos[2]; + iv32 = pos[4] | (pos[5] << 8) | (pos[6] << 16) | (pos[7] << 24); + pos += 8; + + if (tkip_replay_check(iv32, iv16, tkey->rx_iv32, tkey->rx_iv16)) { + if (net_ratelimit()) { + printk(KERN_DEBUG "TKIP: replay detected: STA=%pM" + " previous TSC %08x%04x received TSC " + "%08x%04x\n", hdr->addr2, + tkey->rx_iv32, tkey->rx_iv16, iv32, iv16); + } + tkey->dot11RSNAStatsTKIPReplays++; + return -4; + } + + if (iv32 != tkey->rx_iv32 || !tkey->rx_phase1_done) { + tkip_mixing_phase1(tkey->rx_ttak, tkey->key, hdr->addr2, iv32); + tkey->rx_phase1_done = 1; + } + tkip_mixing_phase2(rc4key, tkey->key, tkey->rx_ttak, iv16); + + plen = skb->len - hdr_len - 12; + + crypto_blkcipher_setkey(tkey->rx_tfm_arc4, rc4key, 16); + sg_init_one(&sg, pos, plen + 4); + if (crypto_blkcipher_decrypt(&desc, &sg, &sg, plen + 4)) { + if (net_ratelimit()) { + printk(KERN_DEBUG ": TKIP: failed to decrypt " + "received packet from %pM\n", + hdr->addr2); + } + return -7; + } + + 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) { + if (iv32 != tkey->rx_iv32) { + /* Previously cached Phase1 result was already lost, so + * it needs to be recalculated for the next packet. */ + tkey->rx_phase1_done = 0; + } + if (net_ratelimit()) { + printk(KERN_DEBUG "TKIP: ICV error detected: STA=" + "%pM\n", hdr->addr2); + } + tkey->dot11RSNAStatsTKIPICVErrors++; + return -5; + } + + /* Update real counters only after Michael MIC verification has + * completed */ + tkey->rx_iv32_new = iv32; + tkey->rx_iv16_new = iv16; + + /* Remove IV and ICV */ + memmove(skb->data + 8, skb->data, hdr_len); + skb_pull(skb, 8); + skb_trim(skb, skb->len - 4); + + return keyidx; +} + +static int michael_mic(struct crypto_hash *tfm_michael, u8 * key, u8 * hdr, + u8 * data, size_t data_len, u8 * mic) +{ + struct hash_desc desc; + struct scatterlist sg[2]; + + if (tfm_michael == NULL) { + printk(KERN_WARNING "michael_mic: tfm_michael == NULL\n"); + return -1; + } + sg_init_table(sg, 2); + sg_set_buf(&sg[0], hdr, 16); + sg_set_buf(&sg[1], data, data_len); + + if (crypto_hash_setkey(tfm_michael, key, 8)) + return -1; + + desc.tfm = tfm_michael; + desc.flags = 0; + return crypto_hash_digest(&desc, sg, data_len + 16, mic); +} + +static void michael_mic_hdr(struct sk_buff *skb, u8 * hdr) +{ + struct ieee80211_hdr *hdr11; + + hdr11 = (struct ieee80211_hdr *)skb->data; + + switch (le16_to_cpu(hdr11->frame_control) & + (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) { + case IEEE80211_FCTL_TODS: + memcpy(hdr, hdr11->addr3, ETH_ALEN); /* DA */ + memcpy(hdr + ETH_ALEN, hdr11->addr2, ETH_ALEN); /* SA */ + break; + case IEEE80211_FCTL_FROMDS: + memcpy(hdr, hdr11->addr1, ETH_ALEN); /* DA */ + memcpy(hdr + ETH_ALEN, hdr11->addr3, ETH_ALEN); /* SA */ + break; + case IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS: + memcpy(hdr, hdr11->addr3, ETH_ALEN); /* DA */ + memcpy(hdr + ETH_ALEN, hdr11->addr4, ETH_ALEN); /* SA */ + break; + case 0: + memcpy(hdr, hdr11->addr1, ETH_ALEN); /* DA */ + memcpy(hdr + ETH_ALEN, hdr11->addr2, ETH_ALEN); /* SA */ + break; + } + + if (ieee80211_is_data_qos(hdr11->frame_control)) { + hdr[12] = le16_to_cpu(*ieee80211_get_qos_ctl(hdr11)) + & IEEE80211_QOS_CTL_TID_MASK; + } else + hdr[12] = 0; /* priority */ + + hdr[13] = hdr[14] = hdr[15] = 0; /* reserved */ +} + +static int lib80211_michael_mic_add(struct sk_buff *skb, int hdr_len, + void *priv) +{ + struct lib80211_tkip_data *tkey = priv; + u8 *pos; + + if (skb_tailroom(skb) < 8 || skb->len < hdr_len) { + printk(KERN_DEBUG "Invalid packet for Michael MIC add " + "(tailroom=%d hdr_len=%d skb->len=%d)\n", + skb_tailroom(skb), hdr_len, skb->len); + return -1; + } + + michael_mic_hdr(skb, tkey->tx_hdr); + pos = skb_put(skb, 8); + if (michael_mic(tkey->tx_tfm_michael, &tkey->key[16], tkey->tx_hdr, + skb->data + hdr_len, skb->len - 8 - hdr_len, pos)) + return -1; + + return 0; +} + +static void lib80211_michael_mic_failure(struct net_device *dev, + struct ieee80211_hdr *hdr, + int keyidx) +{ + union iwreq_data wrqu; + struct iw_michaelmicfailure ev; + + /* TODO: needed parameters: count, keyid, key type, TSC */ + memset(&ev, 0, sizeof(ev)); + ev.flags = keyidx & IW_MICFAILURE_KEY_ID; + if (hdr->addr1[0] & 0x01) + ev.flags |= IW_MICFAILURE_GROUP; + else + ev.flags |= IW_MICFAILURE_PAIRWISE; + ev.src_addr.sa_family = ARPHRD_ETHER; + memcpy(ev.src_addr.sa_data, hdr->addr2, ETH_ALEN); + memset(&wrqu, 0, sizeof(wrqu)); + wrqu.data.length = sizeof(ev); + wireless_send_event(dev, IWEVMICHAELMICFAILURE, &wrqu, (char *)&ev); +} + +static int lib80211_michael_mic_verify(struct sk_buff *skb, int keyidx, + int hdr_len, void *priv) +{ + struct lib80211_tkip_data *tkey = priv; + u8 mic[8]; + + if (!tkey->key_set) + return -1; + + michael_mic_hdr(skb, tkey->rx_hdr); + if (michael_mic(tkey->rx_tfm_michael, &tkey->key[24], tkey->rx_hdr, + skb->data + hdr_len, skb->len - 8 - hdr_len, mic)) + return -1; + if (memcmp(mic, skb->data + skb->len - 8, 8) != 0) { + struct ieee80211_hdr *hdr; + hdr = (struct ieee80211_hdr *)skb->data; + printk(KERN_DEBUG "%s: Michael MIC verification failed for " + "MSDU from %pM keyidx=%d\n", + skb->dev ? skb->dev->name : "N/A", hdr->addr2, + keyidx); + if (skb->dev) + lib80211_michael_mic_failure(skb->dev, hdr, keyidx); + tkey->dot11RSNAStatsTKIPLocalMICFailures++; + return -1; + } + + /* Update TSC counters for RX now that the packet verification has + * completed. */ + tkey->rx_iv32 = tkey->rx_iv32_new; + tkey->rx_iv16 = tkey->rx_iv16_new; + + skb_trim(skb, skb->len - 8); + + return 0; +} + +static int lib80211_tkip_set_key(void *key, int len, u8 * seq, void *priv) +{ + struct lib80211_tkip_data *tkey = priv; + int keyidx; + struct crypto_hash *tfm = tkey->tx_tfm_michael; + struct crypto_blkcipher *tfm2 = tkey->tx_tfm_arc4; + struct crypto_hash *tfm3 = tkey->rx_tfm_michael; + struct crypto_blkcipher *tfm4 = tkey->rx_tfm_arc4; + + keyidx = tkey->key_idx; + memset(tkey, 0, sizeof(*tkey)); + tkey->key_idx = keyidx; + tkey->tx_tfm_michael = tfm; + tkey->tx_tfm_arc4 = tfm2; + tkey->rx_tfm_michael = tfm3; + tkey->rx_tfm_arc4 = tfm4; + if (len == TKIP_KEY_LEN) { + memcpy(tkey->key, key, TKIP_KEY_LEN); + tkey->key_set = 1; + tkey->tx_iv16 = 1; /* TSC is initialized to 1 */ + if (seq) { + tkey->rx_iv32 = (seq[5] << 24) | (seq[4] << 16) | + (seq[3] << 8) | seq[2]; + tkey->rx_iv16 = (seq[1] << 8) | seq[0]; + } + } else if (len == 0) + tkey->key_set = 0; + else + return -1; + + return 0; +} + +static int lib80211_tkip_get_key(void *key, int len, u8 * seq, void *priv) +{ + struct lib80211_tkip_data *tkey = priv; + + if (len < TKIP_KEY_LEN) + return -1; + + if (!tkey->key_set) + return 0; + memcpy(key, tkey->key, TKIP_KEY_LEN); + + if (seq) { + /* Return the sequence number of the last transmitted frame. */ + u16 iv16 = tkey->tx_iv16; + u32 iv32 = tkey->tx_iv32; + if (iv16 == 0) + iv32--; + iv16--; + seq[0] = tkey->tx_iv16; + seq[1] = tkey->tx_iv16 >> 8; + seq[2] = tkey->tx_iv32; + seq[3] = tkey->tx_iv32 >> 8; + seq[4] = tkey->tx_iv32 >> 16; + seq[5] = tkey->tx_iv32 >> 24; + } + + return TKIP_KEY_LEN; +} + +static char *lib80211_tkip_print_stats(char *p, void *priv) +{ + struct lib80211_tkip_data *tkip = priv; + p += sprintf(p, "key[%d] alg=TKIP key_set=%d " + "tx_pn=%02x%02x%02x%02x%02x%02x " + "rx_pn=%02x%02x%02x%02x%02x%02x " + "replays=%d icv_errors=%d local_mic_failures=%d\n", + tkip->key_idx, tkip->key_set, + (tkip->tx_iv32 >> 24) & 0xff, + (tkip->tx_iv32 >> 16) & 0xff, + (tkip->tx_iv32 >> 8) & 0xff, + tkip->tx_iv32 & 0xff, + (tkip->tx_iv16 >> 8) & 0xff, + tkip->tx_iv16 & 0xff, + (tkip->rx_iv32 >> 24) & 0xff, + (tkip->rx_iv32 >> 16) & 0xff, + (tkip->rx_iv32 >> 8) & 0xff, + tkip->rx_iv32 & 0xff, + (tkip->rx_iv16 >> 8) & 0xff, + tkip->rx_iv16 & 0xff, + tkip->dot11RSNAStatsTKIPReplays, + tkip->dot11RSNAStatsTKIPICVErrors, + tkip->dot11RSNAStatsTKIPLocalMICFailures); + return p; +} + +static struct lib80211_crypto_ops lib80211_crypt_tkip = { + .name = "TKIP", + .init = lib80211_tkip_init, + .deinit = lib80211_tkip_deinit, + .build_iv = lib80211_tkip_hdr, + .encrypt_mpdu = lib80211_tkip_encrypt, + .decrypt_mpdu = lib80211_tkip_decrypt, + .encrypt_msdu = lib80211_michael_mic_add, + .decrypt_msdu = lib80211_michael_mic_verify, + .set_key = lib80211_tkip_set_key, + .get_key = lib80211_tkip_get_key, + .print_stats = lib80211_tkip_print_stats, + .extra_mpdu_prefix_len = 4 + 4, /* IV + ExtIV */ + .extra_mpdu_postfix_len = 4, /* ICV */ + .extra_msdu_postfix_len = 8, /* MIC */ + .get_flags = lib80211_tkip_get_flags, + .set_flags = lib80211_tkip_set_flags, + .owner = THIS_MODULE, +}; + +static int __init lib80211_crypto_tkip_init(void) +{ + return lib80211_register_crypto_ops(&lib80211_crypt_tkip); +} + +static void __exit lib80211_crypto_tkip_exit(void) +{ + lib80211_unregister_crypto_ops(&lib80211_crypt_tkip); +} + +module_init(lib80211_crypto_tkip_init); +module_exit(lib80211_crypto_tkip_exit); diff --git a/net/wireless/lib80211_crypt_wep.c b/net/wireless/lib80211_crypt_wep.c new file mode 100644 index 000000000000..6d41e05ca33b --- /dev/null +++ b/net/wireless/lib80211_crypt_wep.c @@ -0,0 +1,296 @@ +/* + * lib80211 crypt: host-based WEP encryption implementation for lib80211 + * + * Copyright (c) 2002-2004, Jouni Malinen <j@w1.fi> + * Copyright (c) 2008, John W. Linville <linville@tuxdriver.com> + * + * 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/err.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/random.h> +#include <linux/scatterlist.h> +#include <linux/skbuff.h> +#include <linux/mm.h> +#include <asm/string.h> + +#include <net/lib80211.h> + +#include <linux/crypto.h> +#include <linux/crc32.h> + +MODULE_AUTHOR("Jouni Malinen"); +MODULE_DESCRIPTION("lib80211 crypt: WEP"); +MODULE_LICENSE("GPL"); + +struct lib80211_wep_data { + u32 iv; +#define WEP_KEY_LEN 13 + u8 key[WEP_KEY_LEN + 1]; + u8 key_len; + u8 key_idx; + struct crypto_blkcipher *tx_tfm; + struct crypto_blkcipher *rx_tfm; +}; + +static void *lib80211_wep_init(int keyidx) +{ + struct lib80211_wep_data *priv; + + priv = kzalloc(sizeof(*priv), GFP_ATOMIC); + if (priv == NULL) + goto fail; + priv->key_idx = keyidx; + + priv->tx_tfm = crypto_alloc_blkcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC); + if (IS_ERR(priv->tx_tfm)) { + printk(KERN_DEBUG "lib80211_crypt_wep: could not allocate " + "crypto API arc4\n"); + priv->tx_tfm = NULL; + goto fail; + } + + priv->rx_tfm = crypto_alloc_blkcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC); + if (IS_ERR(priv->rx_tfm)) { + printk(KERN_DEBUG "lib80211_crypt_wep: could not allocate " + "crypto API arc4\n"); + priv->rx_tfm = NULL; + goto fail; + } + /* start WEP IV from a random value */ + get_random_bytes(&priv->iv, 4); + + return priv; + + fail: + if (priv) { + if (priv->tx_tfm) + crypto_free_blkcipher(priv->tx_tfm); + if (priv->rx_tfm) + crypto_free_blkcipher(priv->rx_tfm); + kfree(priv); + } + return NULL; +} + +static void lib80211_wep_deinit(void *priv) +{ + struct lib80211_wep_data *_priv = priv; + if (_priv) { + if (_priv->tx_tfm) + crypto_free_blkcipher(_priv->tx_tfm); + if (_priv->rx_tfm) + crypto_free_blkcipher(_priv->rx_tfm); + } + kfree(priv); +} + +/* Add WEP IV/key info to a frame that has at least 4 bytes of headroom */ +static int lib80211_wep_build_iv(struct sk_buff *skb, int hdr_len, + u8 *key, int keylen, void *priv) +{ + struct lib80211_wep_data *wep = priv; + u32 klen, len; + u8 *pos; + + if (skb_headroom(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++ = (wep->iv >> 16) & 0xff; + *pos++ = (wep->iv >> 8) & 0xff; + *pos++ = wep->iv & 0xff; + *pos++ = wep->key_idx << 6; + + return 0; +} + +/* 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 lib80211_wep_encrypt(struct sk_buff *skb, int hdr_len, void *priv) +{ + struct lib80211_wep_data *wep = priv; + struct blkcipher_desc desc = { .tfm = wep->tx_tfm }; + u32 crc, klen, len; + u8 *pos, *icv; + struct scatterlist sg; + u8 key[WEP_KEY_LEN + 3]; + + /* other checks are in lib80211_wep_build_iv */ + if (skb_tailroom(skb) < 4) + return -1; + + /* add the IV to the frame */ + if (lib80211_wep_build_iv(skb, hdr_len, NULL, 0, priv)) + return -1; + + /* Copy the IV into the first 3 bytes of the key */ + skb_copy_from_linear_data_offset(skb, hdr_len, key, 3); + + /* Copy rest of the WEP key (the secret part) */ + memcpy(key + 3, wep->key, wep->key_len); + + len = skb->len - hdr_len - 4; + pos = skb->data + hdr_len + 4; + klen = 3 + wep->key_len; + + /* Append little-endian CRC32 over only the data 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_blkcipher_setkey(wep->tx_tfm, key, klen); + sg_init_one(&sg, pos, len + 4); + return crypto_blkcipher_encrypt(&desc, &sg, &sg, len + 4); +} + +/* 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 lib80211_wep_decrypt(struct sk_buff *skb, int hdr_len, void *priv) +{ + struct lib80211_wep_data *wep = priv; + struct blkcipher_desc desc = { .tfm = wep->rx_tfm }; + 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_blkcipher_setkey(wep->rx_tfm, key, klen); + sg_init_one(&sg, pos, plen + 4); + if (crypto_blkcipher_decrypt(&desc, &sg, &sg, plen + 4)) + return -7; + + 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 lib80211_wep_set_key(void *key, int len, u8 * seq, void *priv) +{ + struct lib80211_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 lib80211_wep_get_key(void *key, int len, u8 * seq, void *priv) +{ + struct lib80211_wep_data *wep = priv; + + if (len < wep->key_len) + return -1; + + memcpy(key, wep->key, wep->key_len); + + return wep->key_len; +} + +static char *lib80211_wep_print_stats(char *p, void *priv) +{ + struct lib80211_wep_data *wep = priv; + p += sprintf(p, "key[%d] alg=WEP len=%d\n", wep->key_idx, wep->key_len); + return p; +} + +static struct lib80211_crypto_ops lib80211_crypt_wep = { + .name = "WEP", + .init = lib80211_wep_init, + .deinit = lib80211_wep_deinit, + .build_iv = lib80211_wep_build_iv, + .encrypt_mpdu = lib80211_wep_encrypt, + .decrypt_mpdu = lib80211_wep_decrypt, + .encrypt_msdu = NULL, + .decrypt_msdu = NULL, + .set_key = lib80211_wep_set_key, + .get_key = lib80211_wep_get_key, + .print_stats = lib80211_wep_print_stats, + .extra_mpdu_prefix_len = 4, /* IV */ + .extra_mpdu_postfix_len = 4, /* ICV */ + .owner = THIS_MODULE, +}; + +static int __init lib80211_crypto_wep_init(void) +{ + return lib80211_register_crypto_ops(&lib80211_crypt_wep); +} + +static void __exit lib80211_crypto_wep_exit(void) +{ + lib80211_unregister_crypto_ops(&lib80211_crypt_wep); +} + +module_init(lib80211_crypto_wep_init); +module_exit(lib80211_crypto_wep_exit); |