diff options
Diffstat (limited to 'net/ieee80211/ieee80211_crypt_ccmp.c')
-rw-r--r-- | net/ieee80211/ieee80211_crypt_ccmp.c | 492 |
1 files changed, 0 insertions, 492 deletions
diff --git a/net/ieee80211/ieee80211_crypt_ccmp.c b/net/ieee80211/ieee80211_crypt_ccmp.c deleted file mode 100644 index bea04af0b482..000000000000 --- a/net/ieee80211/ieee80211_crypt_ccmp.c +++ /dev/null @@ -1,492 +0,0 @@ -/* - * Host AP crypt: host-based CCMP encryption implementation for Host AP driver - * - * Copyright (c) 2003-2004, Jouni Malinen <j@w1.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/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 <net/ieee80211.h> - -#include <linux/crypto.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 ieee80211_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 ieee80211_ccmp_aes_encrypt(struct crypto_cipher *tfm, - const u8 pt[16], u8 ct[16]) -{ - crypto_cipher_encrypt_one(tfm, ct, pt); -} - -static void *ieee80211_ccmp_init(int key_idx) -{ - struct ieee80211_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 "ieee80211_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 ieee80211_ccmp_deinit(void *priv) -{ - struct ieee80211_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_4addr *hdr, - u8 * pn, size_t dlen, u8 * b0, u8 * auth, u8 * s0) -{ - u8 *pos, qc = 0; - size_t aad_len; - u16 fc; - int a4_included, qc_included; - u8 aad[2 * AES_BLOCK_LEN]; - - fc = le16_to_cpu(hdr->frame_ctl); - a4_included = ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) == - (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)); - qc_included = ((WLAN_FC_GET_TYPE(fc) == IEEE80211_FTYPE_DATA) && - (WLAN_FC_GET_STYPE(fc) & IEEE80211_STYPE_QOS_DATA)); - 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_ctl; - 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 */ - ieee80211_ccmp_aes_encrypt(tfm, b0, auth); - xor_block(auth, aad, AES_BLOCK_LEN); - ieee80211_ccmp_aes_encrypt(tfm, auth, auth); - xor_block(auth, &aad[AES_BLOCK_LEN], AES_BLOCK_LEN); - ieee80211_ccmp_aes_encrypt(tfm, auth, auth); - b0[0] &= 0x07; - b0[14] = b0[15] = 0; - ieee80211_ccmp_aes_encrypt(tfm, b0, s0); -} - -static int ieee80211_ccmp_hdr(struct sk_buff *skb, int hdr_len, - u8 *aeskey, int keylen, void *priv) -{ - struct ieee80211_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 ieee80211_ccmp_encrypt(struct sk_buff *skb, int hdr_len, void *priv) -{ - struct ieee80211_ccmp_data *key = priv; - int data_len, i, blocks, last, len; - u8 *pos, *mic; - struct ieee80211_hdr_4addr *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 = ieee80211_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_4addr *)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); - ieee80211_ccmp_aes_encrypt(key->tfm, b, b); - /* Encryption, with counter */ - b0[14] = (i >> 8) & 0xff; - b0[15] = i & 0xff; - ieee80211_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 ieee80211_ccmp_decrypt(struct sk_buff *skb, int hdr_len, void *priv) -{ - struct ieee80211_ccmp_data *key = priv; - u8 keyidx, *pos; - struct ieee80211_hdr_4addr *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_4addr *)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 (ieee80211_ratelimit_debug(IEEE80211_DL_DROP)) { - IEEE80211_DEBUG_DROP("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; - ieee80211_ccmp_aes_encrypt(key->tfm, b0, b); - xor_block(pos, b, len); - /* Authentication */ - xor_block(a, pos, len); - ieee80211_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 ieee80211_ccmp_set_key(void *key, int len, u8 * seq, void *priv) -{ - struct ieee80211_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 ieee80211_ccmp_get_key(void *key, int len, u8 * seq, void *priv) -{ - struct ieee80211_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 *ieee80211_ccmp_print_stats(char *p, void *priv) -{ - struct ieee80211_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 ieee80211_crypto_ops ieee80211_crypt_ccmp = { - .name = "CCMP", - .init = ieee80211_ccmp_init, - .deinit = ieee80211_ccmp_deinit, - .build_iv = ieee80211_ccmp_hdr, - .encrypt_mpdu = ieee80211_ccmp_encrypt, - .decrypt_mpdu = ieee80211_ccmp_decrypt, - .encrypt_msdu = NULL, - .decrypt_msdu = NULL, - .set_key = ieee80211_ccmp_set_key, - .get_key = ieee80211_ccmp_get_key, - .print_stats = ieee80211_ccmp_print_stats, - .extra_mpdu_prefix_len = CCMP_HDR_LEN, - .extra_mpdu_postfix_len = CCMP_MIC_LEN, - .owner = THIS_MODULE, -}; - -static int __init ieee80211_crypto_ccmp_init(void) -{ - return ieee80211_register_crypto_ops(&ieee80211_crypt_ccmp); -} - -static void __exit ieee80211_crypto_ccmp_exit(void) -{ - ieee80211_unregister_crypto_ops(&ieee80211_crypt_ccmp); -} - -module_init(ieee80211_crypto_ccmp_init); -module_exit(ieee80211_crypto_ccmp_exit); |