| /* |
| * Copyright 2002-2004, Instant802 Networks, Inc. |
| * Copyright 2008, 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. |
| */ |
| |
| #include <linux/netdevice.h> |
| #include <linux/types.h> |
| #include <linux/skbuff.h> |
| #include <linux/compiler.h> |
| #include <linux/ieee80211.h> |
| #include <linux/gfp.h> |
| #include <asm/unaligned.h> |
| #include <net/mac80211.h> |
| #include <crypto/aes.h> |
| |
| #include "ieee80211_i.h" |
| #include "michael.h" |
| #include "tkip.h" |
| #include "aes_ccm.h" |
| #include "aes_cmac.h" |
| #include "wpa.h" |
| |
| ieee80211_tx_result |
| ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx) |
| { |
| u8 *data, *key, *mic; |
| size_t data_len; |
| unsigned int hdrlen; |
| struct ieee80211_hdr *hdr; |
| struct sk_buff *skb = tx->skb; |
| struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
| int tail; |
| |
| hdr = (struct ieee80211_hdr *)skb->data; |
| if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP || |
| skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control)) |
| return TX_CONTINUE; |
| |
| hdrlen = ieee80211_hdrlen(hdr->frame_control); |
| if (skb->len < hdrlen) |
| return TX_DROP; |
| |
| data = skb->data + hdrlen; |
| data_len = skb->len - hdrlen; |
| |
| if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) { |
| /* Need to use software crypto for the test */ |
| info->control.hw_key = NULL; |
| } |
| |
| if (info->control.hw_key && |
| (info->flags & IEEE80211_TX_CTL_DONTFRAG || |
| tx->local->ops->set_frag_threshold) && |
| !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) { |
| /* hwaccel - with no need for SW-generated MMIC */ |
| return TX_CONTINUE; |
| } |
| |
| tail = MICHAEL_MIC_LEN; |
| if (!info->control.hw_key) |
| tail += TKIP_ICV_LEN; |
| |
| if (WARN_ON(skb_tailroom(skb) < tail || |
| skb_headroom(skb) < TKIP_IV_LEN)) |
| return TX_DROP; |
| |
| key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY]; |
| mic = skb_put(skb, MICHAEL_MIC_LEN); |
| michael_mic(key, hdr, data, data_len, mic); |
| if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) |
| mic[0]++; |
| |
| return TX_CONTINUE; |
| } |
| |
| |
| ieee80211_rx_result |
| ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx) |
| { |
| u8 *data, *key = NULL; |
| size_t data_len; |
| unsigned int hdrlen; |
| u8 mic[MICHAEL_MIC_LEN]; |
| struct sk_buff *skb = rx->skb; |
| struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
| struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; |
| |
| /* |
| * it makes no sense to check for MIC errors on anything other |
| * than data frames. |
| */ |
| if (!ieee80211_is_data_present(hdr->frame_control)) |
| return RX_CONTINUE; |
| |
| /* |
| * No way to verify the MIC if the hardware stripped it or |
| * the IV with the key index. In this case we have solely rely |
| * on the driver to set RX_FLAG_MMIC_ERROR in the event of a |
| * MIC failure report. |
| */ |
| if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) { |
| if (status->flag & RX_FLAG_MMIC_ERROR) |
| goto mic_fail; |
| |
| if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key && |
| rx->key->conf.cipher == WLAN_CIPHER_SUITE_TKIP) |
| goto update_iv; |
| |
| return RX_CONTINUE; |
| } |
| |
| /* |
| * Some hardware seems to generate Michael MIC failure reports; even |
| * though, the frame was not encrypted with TKIP and therefore has no |
| * MIC. Ignore the flag them to avoid triggering countermeasures. |
| */ |
| if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP || |
| !(status->flag & RX_FLAG_DECRYPTED)) |
| return RX_CONTINUE; |
| |
| if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) { |
| /* |
| * APs with pairwise keys should never receive Michael MIC |
| * errors for non-zero keyidx because these are reserved for |
| * group keys and only the AP is sending real multicast |
| * frames in the BSS. ( |
| */ |
| return RX_DROP_UNUSABLE; |
| } |
| |
| if (status->flag & RX_FLAG_MMIC_ERROR) |
| goto mic_fail; |
| |
| hdrlen = ieee80211_hdrlen(hdr->frame_control); |
| if (skb->len < hdrlen + MICHAEL_MIC_LEN) |
| return RX_DROP_UNUSABLE; |
| |
| if (skb_linearize(rx->skb)) |
| return RX_DROP_UNUSABLE; |
| hdr = (void *)skb->data; |
| |
| data = skb->data + hdrlen; |
| data_len = skb->len - hdrlen - MICHAEL_MIC_LEN; |
| key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY]; |
| michael_mic(key, hdr, data, data_len, mic); |
| if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0) |
| goto mic_fail; |
| |
| /* remove Michael MIC from payload */ |
| skb_trim(skb, skb->len - MICHAEL_MIC_LEN); |
| |
| update_iv: |
| /* update IV in key information to be able to detect replays */ |
| rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32; |
| rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16; |
| |
| return RX_CONTINUE; |
| |
| mic_fail: |
| /* |
| * In some cases the key can be unset - e.g. a multicast packet, in |
| * a driver that supports HW encryption. Send up the key idx only if |
| * the key is set. |
| */ |
| mac80211_ev_michael_mic_failure(rx->sdata, |
| rx->key ? rx->key->conf.keyidx : -1, |
| (void *) skb->data, NULL, GFP_ATOMIC); |
| return RX_DROP_UNUSABLE; |
| } |
| |
| |
| static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) |
| { |
| struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; |
| struct ieee80211_key *key = tx->key; |
| struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
| unsigned long flags; |
| unsigned int hdrlen; |
| int len, tail; |
| u8 *pos; |
| |
| if (info->control.hw_key && |
| !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV)) { |
| /* hwaccel - with no need for software-generated IV */ |
| return 0; |
| } |
| |
| hdrlen = ieee80211_hdrlen(hdr->frame_control); |
| len = skb->len - hdrlen; |
| |
| if (info->control.hw_key) |
| tail = 0; |
| else |
| tail = TKIP_ICV_LEN; |
| |
| if (WARN_ON(skb_tailroom(skb) < tail || |
| skb_headroom(skb) < TKIP_IV_LEN)) |
| return -1; |
| |
| pos = skb_push(skb, TKIP_IV_LEN); |
| memmove(pos, pos + TKIP_IV_LEN, hdrlen); |
| pos += hdrlen; |
| |
| /* Increase IV for the frame */ |
| spin_lock_irqsave(&key->u.tkip.txlock, flags); |
| key->u.tkip.tx.iv16++; |
| if (key->u.tkip.tx.iv16 == 0) |
| key->u.tkip.tx.iv32++; |
| pos = ieee80211_tkip_add_iv(pos, key); |
| spin_unlock_irqrestore(&key->u.tkip.txlock, flags); |
| |
| /* hwaccel - with software IV */ |
| if (info->control.hw_key) |
| return 0; |
| |
| /* Add room for ICV */ |
| skb_put(skb, TKIP_ICV_LEN); |
| |
| return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm, |
| key, skb, pos, len); |
| } |
| |
| |
| ieee80211_tx_result |
| ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx) |
| { |
| struct sk_buff *skb; |
| |
| ieee80211_tx_set_protected(tx); |
| |
| skb_queue_walk(&tx->skbs, skb) { |
| if (tkip_encrypt_skb(tx, skb) < 0) |
| return TX_DROP; |
| } |
| |
| return TX_CONTINUE; |
| } |
| |
| |
| ieee80211_rx_result |
| ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx) |
| { |
| struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; |
| int hdrlen, res, hwaccel = 0; |
| struct ieee80211_key *key = rx->key; |
| struct sk_buff *skb = rx->skb; |
| struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
| |
| hdrlen = ieee80211_hdrlen(hdr->frame_control); |
| |
| if (!ieee80211_is_data(hdr->frame_control)) |
| return RX_CONTINUE; |
| |
| if (!rx->sta || skb->len - hdrlen < 12) |
| return RX_DROP_UNUSABLE; |
| |
| /* it may be possible to optimize this a bit more */ |
| if (skb_linearize(rx->skb)) |
| return RX_DROP_UNUSABLE; |
| hdr = (void *)skb->data; |
| |
| /* |
| * Let TKIP code verify IV, but skip decryption. |
| * In the case where hardware checks the IV as well, |
| * we don't even get here, see ieee80211_rx_h_decrypt() |
| */ |
| if (status->flag & RX_FLAG_DECRYPTED) |
| hwaccel = 1; |
| |
| res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm, |
| key, skb->data + hdrlen, |
| skb->len - hdrlen, rx->sta->sta.addr, |
| hdr->addr1, hwaccel, rx->security_idx, |
| &rx->tkip_iv32, |
| &rx->tkip_iv16); |
| if (res != TKIP_DECRYPT_OK) |
| return RX_DROP_UNUSABLE; |
| |
| /* Trim ICV */ |
| skb_trim(skb, skb->len - TKIP_ICV_LEN); |
| |
| /* Remove IV */ |
| memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen); |
| skb_pull(skb, TKIP_IV_LEN); |
| |
| return RX_CONTINUE; |
| } |
| |
| |
| static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *scratch, |
| int encrypted) |
| { |
| __le16 mask_fc; |
| int a4_included, mgmt; |
| u8 qos_tid; |
| u8 *b_0, *aad; |
| u16 data_len, len_a; |
| unsigned int hdrlen; |
| struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; |
| |
| memset(scratch, 0, 6 * AES_BLOCK_SIZE); |
| |
| b_0 = scratch + 3 * AES_BLOCK_SIZE; |
| aad = scratch + 4 * AES_BLOCK_SIZE; |
| |
| /* |
| * Mask FC: zero subtype b4 b5 b6 (if not mgmt) |
| * Retry, PwrMgt, MoreData; set Protected |
| */ |
| mgmt = ieee80211_is_mgmt(hdr->frame_control); |
| mask_fc = hdr->frame_control; |
| mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | |
| IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA); |
| if (!mgmt) |
| mask_fc &= ~cpu_to_le16(0x0070); |
| mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); |
| |
| hdrlen = ieee80211_hdrlen(hdr->frame_control); |
| len_a = hdrlen - 2; |
| a4_included = ieee80211_has_a4(hdr->frame_control); |
| |
| if (ieee80211_is_data_qos(hdr->frame_control)) |
| qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; |
| else |
| qos_tid = 0; |
| |
| data_len = skb->len - hdrlen - CCMP_HDR_LEN; |
| if (encrypted) |
| data_len -= CCMP_MIC_LEN; |
| |
| /* First block, b_0 */ |
| b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */ |
| /* Nonce: Nonce Flags | A2 | PN |
| * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7) |
| */ |
| b_0[1] = qos_tid | (mgmt << 4); |
| memcpy(&b_0[2], hdr->addr2, ETH_ALEN); |
| memcpy(&b_0[8], pn, CCMP_PN_LEN); |
| /* l(m) */ |
| put_unaligned_be16(data_len, &b_0[14]); |
| |
| /* AAD (extra authenticate-only data) / masked 802.11 header |
| * FC | A1 | A2 | A3 | SC | [A4] | [QC] */ |
| put_unaligned_be16(len_a, &aad[0]); |
| put_unaligned(mask_fc, (__le16 *)&aad[2]); |
| memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN); |
| |
| /* Mask Seq#, leave Frag# */ |
| aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f; |
| aad[23] = 0; |
| |
| if (a4_included) { |
| memcpy(&aad[24], hdr->addr4, ETH_ALEN); |
| aad[30] = qos_tid; |
| aad[31] = 0; |
| } else { |
| memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN); |
| aad[24] = qos_tid; |
| } |
| } |
| |
| |
| static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id) |
| { |
| hdr[0] = pn[5]; |
| hdr[1] = pn[4]; |
| hdr[2] = 0; |
| hdr[3] = 0x20 | (key_id << 6); |
| hdr[4] = pn[3]; |
| hdr[5] = pn[2]; |
| hdr[6] = pn[1]; |
| hdr[7] = pn[0]; |
| } |
| |
| |
| static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr) |
| { |
| pn[0] = hdr[7]; |
| pn[1] = hdr[6]; |
| pn[2] = hdr[5]; |
| pn[3] = hdr[4]; |
| pn[4] = hdr[1]; |
| pn[5] = hdr[0]; |
| } |
| |
| |
| static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) |
| { |
| struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; |
| struct ieee80211_key *key = tx->key; |
| struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
| int hdrlen, len, tail; |
| u8 *pos; |
| u8 pn[6]; |
| u64 pn64; |
| u8 scratch[6 * AES_BLOCK_SIZE]; |
| |
| if (info->control.hw_key && |
| !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) && |
| !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) { |
| /* |
| * hwaccel has no need for preallocated room for CCMP |
| * header or MIC fields |
| */ |
| return 0; |
| } |
| |
| hdrlen = ieee80211_hdrlen(hdr->frame_control); |
| len = skb->len - hdrlen; |
| |
| if (info->control.hw_key) |
| tail = 0; |
| else |
| tail = CCMP_MIC_LEN; |
| |
| if (WARN_ON(skb_tailroom(skb) < tail || |
| skb_headroom(skb) < CCMP_HDR_LEN)) |
| return -1; |
| |
| pos = skb_push(skb, CCMP_HDR_LEN); |
| memmove(pos, pos + CCMP_HDR_LEN, hdrlen); |
| |
| /* the HW only needs room for the IV, but not the actual IV */ |
| if (info->control.hw_key && |
| (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) |
| return 0; |
| |
| hdr = (struct ieee80211_hdr *) pos; |
| pos += hdrlen; |
| |
| pn64 = atomic64_inc_return(&key->u.ccmp.tx_pn); |
| |
| pn[5] = pn64; |
| pn[4] = pn64 >> 8; |
| pn[3] = pn64 >> 16; |
| pn[2] = pn64 >> 24; |
| pn[1] = pn64 >> 32; |
| pn[0] = pn64 >> 40; |
| |
| ccmp_pn2hdr(pos, pn, key->conf.keyidx); |
| |
| /* hwaccel - with software CCMP header */ |
| if (info->control.hw_key) |
| return 0; |
| |
| pos += CCMP_HDR_LEN; |
| ccmp_special_blocks(skb, pn, scratch, 0); |
| ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, scratch, pos, len, |
| pos, skb_put(skb, CCMP_MIC_LEN)); |
| |
| return 0; |
| } |
| |
| |
| ieee80211_tx_result |
| ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx) |
| { |
| struct sk_buff *skb; |
| |
| ieee80211_tx_set_protected(tx); |
| |
| skb_queue_walk(&tx->skbs, skb) { |
| if (ccmp_encrypt_skb(tx, skb) < 0) |
| return TX_DROP; |
| } |
| |
| return TX_CONTINUE; |
| } |
| |
| |
| ieee80211_rx_result |
| ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx) |
| { |
| struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; |
| int hdrlen; |
| struct ieee80211_key *key = rx->key; |
| struct sk_buff *skb = rx->skb; |
| struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
| u8 pn[CCMP_PN_LEN]; |
| int data_len; |
| int queue; |
| |
| hdrlen = ieee80211_hdrlen(hdr->frame_control); |
| |
| if (!ieee80211_is_data(hdr->frame_control) && |
| !ieee80211_is_robust_mgmt_frame(hdr)) |
| return RX_CONTINUE; |
| |
| data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN; |
| if (!rx->sta || data_len < 0) |
| return RX_DROP_UNUSABLE; |
| |
| if (status->flag & RX_FLAG_DECRYPTED) { |
| if (!pskb_may_pull(rx->skb, hdrlen + CCMP_HDR_LEN)) |
| return RX_DROP_UNUSABLE; |
| } else { |
| if (skb_linearize(rx->skb)) |
| return RX_DROP_UNUSABLE; |
| } |
| |
| ccmp_hdr2pn(pn, skb->data + hdrlen); |
| |
| queue = rx->security_idx; |
| |
| if (memcmp(pn, key->u.ccmp.rx_pn[queue], CCMP_PN_LEN) <= 0) { |
| key->u.ccmp.replays++; |
| return RX_DROP_UNUSABLE; |
| } |
| |
| if (!(status->flag & RX_FLAG_DECRYPTED)) { |
| u8 scratch[6 * AES_BLOCK_SIZE]; |
| /* hardware didn't decrypt/verify MIC */ |
| ccmp_special_blocks(skb, pn, scratch, 1); |
| |
| if (ieee80211_aes_ccm_decrypt( |
| key->u.ccmp.tfm, scratch, |
| skb->data + hdrlen + CCMP_HDR_LEN, data_len, |
| skb->data + skb->len - CCMP_MIC_LEN, |
| skb->data + hdrlen + CCMP_HDR_LEN)) |
| return RX_DROP_UNUSABLE; |
| } |
| |
| memcpy(key->u.ccmp.rx_pn[queue], pn, CCMP_PN_LEN); |
| |
| /* Remove CCMP header and MIC */ |
| if (pskb_trim(skb, skb->len - CCMP_MIC_LEN)) |
| return RX_DROP_UNUSABLE; |
| memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen); |
| skb_pull(skb, CCMP_HDR_LEN); |
| |
| return RX_CONTINUE; |
| } |
| |
| |
| static void bip_aad(struct sk_buff *skb, u8 *aad) |
| { |
| /* BIP AAD: FC(masked) || A1 || A2 || A3 */ |
| |
| /* FC type/subtype */ |
| aad[0] = skb->data[0]; |
| /* Mask FC Retry, PwrMgt, MoreData flags to zero */ |
| aad[1] = skb->data[1] & ~(BIT(4) | BIT(5) | BIT(6)); |
| /* A1 || A2 || A3 */ |
| memcpy(aad + 2, skb->data + 4, 3 * ETH_ALEN); |
| } |
| |
| |
| static inline void bip_ipn_set64(u8 *d, u64 pn) |
| { |
| *d++ = pn; |
| *d++ = pn >> 8; |
| *d++ = pn >> 16; |
| *d++ = pn >> 24; |
| *d++ = pn >> 32; |
| *d = pn >> 40; |
| } |
| |
| static inline void bip_ipn_swap(u8 *d, const u8 *s) |
| { |
| *d++ = s[5]; |
| *d++ = s[4]; |
| *d++ = s[3]; |
| *d++ = s[2]; |
| *d++ = s[1]; |
| *d = s[0]; |
| } |
| |
| |
| ieee80211_tx_result |
| ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx) |
| { |
| struct sk_buff *skb; |
| struct ieee80211_tx_info *info; |
| struct ieee80211_key *key = tx->key; |
| struct ieee80211_mmie *mmie; |
| u8 aad[20]; |
| u64 pn64; |
| |
| if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) |
| return TX_DROP; |
| |
| skb = skb_peek(&tx->skbs); |
| |
| info = IEEE80211_SKB_CB(skb); |
| |
| if (info->control.hw_key) |
| return TX_CONTINUE; |
| |
| if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) |
| return TX_DROP; |
| |
| mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie)); |
| mmie->element_id = WLAN_EID_MMIE; |
| mmie->length = sizeof(*mmie) - 2; |
| mmie->key_id = cpu_to_le16(key->conf.keyidx); |
| |
| /* PN = PN + 1 */ |
| pn64 = atomic64_inc_return(&key->u.aes_cmac.tx_pn); |
| |
| bip_ipn_set64(mmie->sequence_number, pn64); |
| |
| bip_aad(skb, aad); |
| |
| /* |
| * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64) |
| */ |
| ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, |
| skb->data + 24, skb->len - 24, mmie->mic); |
| |
| return TX_CONTINUE; |
| } |
| |
| |
| ieee80211_rx_result |
| ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx) |
| { |
| struct sk_buff *skb = rx->skb; |
| struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
| struct ieee80211_key *key = rx->key; |
| struct ieee80211_mmie *mmie; |
| u8 aad[20], mic[8], ipn[6]; |
| struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; |
| |
| if (!ieee80211_is_mgmt(hdr->frame_control)) |
| return RX_CONTINUE; |
| |
| /* management frames are already linear */ |
| |
| if (skb->len < 24 + sizeof(*mmie)) |
| return RX_DROP_UNUSABLE; |
| |
| mmie = (struct ieee80211_mmie *) |
| (skb->data + skb->len - sizeof(*mmie)); |
| if (mmie->element_id != WLAN_EID_MMIE || |
| mmie->length != sizeof(*mmie) - 2) |
| return RX_DROP_UNUSABLE; /* Invalid MMIE */ |
| |
| bip_ipn_swap(ipn, mmie->sequence_number); |
| |
| if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { |
| key->u.aes_cmac.replays++; |
| return RX_DROP_UNUSABLE; |
| } |
| |
| if (!(status->flag & RX_FLAG_DECRYPTED)) { |
| /* hardware didn't decrypt/verify MIC */ |
| bip_aad(skb, aad); |
| ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, |
| skb->data + 24, skb->len - 24, mic); |
| if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) { |
| key->u.aes_cmac.icverrors++; |
| return RX_DROP_UNUSABLE; |
| } |
| } |
| |
| memcpy(key->u.aes_cmac.rx_pn, ipn, 6); |
| |
| /* Remove MMIE */ |
| skb_trim(skb, skb->len - sizeof(*mmie)); |
| |
| return RX_CONTINUE; |
| } |
| |
| ieee80211_tx_result |
| ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx) |
| { |
| struct sk_buff *skb; |
| struct ieee80211_tx_info *info = NULL; |
| |
| skb_queue_walk(&tx->skbs, skb) { |
| info = IEEE80211_SKB_CB(skb); |
| |
| /* handle hw-only algorithm */ |
| if (!info->control.hw_key) |
| return TX_DROP; |
| } |
| |
| ieee80211_tx_set_protected(tx); |
| |
| return TX_CONTINUE; |
| } |