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-rw-r--r--net/mac80211/wpa.c630
1 files changed, 630 insertions, 0 deletions
diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c
new file mode 100644
index 00000000..aa1c40ab
--- /dev/null
+++ b/net/mac80211/wpa.c
@@ -0,0 +1,630 @@
+/*
+ * 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 "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 &&
+ !(tx->flags & IEEE80211_TX_FRAGMENTED) &&
+ !(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;
+ int queue = rx->queue;
+
+ /* otherwise, TKIP is vulnerable to TID 0 vs. non-QoS replays */
+ if (rx->queue == NUM_RX_DATA_QUEUES - 1)
+ queue = 0;
+
+ /*
+ * 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)
+ 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;
+
+ 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[queue].iv32 = rx->tkip_iv32;
+ rx->key->u.tkip.rx[queue].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 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 */
+ key->u.tkip.tx.iv16++;
+ if (key->u.tkip.tx.iv16 == 0)
+ key->u.tkip.tx.iv32++;
+
+ pos = ieee80211_tkip_add_iv(pos, key, key->u.tkip.tx.iv16);
+
+ /* hwaccel - with software IV */
+ if (info->control.hw_key)
+ return 0;
+
+ /* Add room for ICV */
+ skb_put(skb, TKIP_ICV_LEN);
+
+ hdr = (struct ieee80211_hdr *) skb->data;
+ return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
+ key, pos, len, hdr->addr2);
+}
+
+
+ieee80211_tx_result
+ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
+{
+ struct sk_buff *skb = tx->skb;
+
+ ieee80211_tx_set_protected(tx);
+
+ do {
+ if (tkip_encrypt_skb(tx, skb) < 0)
+ return TX_DROP;
+ } while ((skb = skb->next));
+
+ 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);
+ int queue = rx->queue;
+
+ /* otherwise, TKIP is vulnerable to TID 0 vs. non-QoS replays */
+ if (rx->queue == NUM_RX_DATA_QUEUES - 1)
+ queue = 0;
+
+ 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;
+
+ /*
+ * 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, queue,
+ &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;
+
+ b_0 = scratch + 3 * AES_BLOCK_LEN;
+ aad = scratch + 4 * AES_BLOCK_LEN;
+
+ /*
+ * 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, *pn;
+ int i;
+
+ if (info->control.hw_key &&
+ !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV)) {
+ /*
+ * 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);
+ hdr = (struct ieee80211_hdr *) pos;
+ pos += hdrlen;
+
+ /* PN = PN + 1 */
+ pn = key->u.ccmp.tx_pn;
+
+ for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
+ pn[i]++;
+ if (pn[i])
+ break;
+ }
+
+ 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, key->u.ccmp.tx_crypto_buf, 0);
+ ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, key->u.ccmp.tx_crypto_buf, 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 = tx->skb;
+
+ ieee80211_tx_set_protected(tx);
+
+ do {
+ if (ccmp_encrypt_skb(tx, skb) < 0)
+ return TX_DROP;
+ } while ((skb = skb->next));
+
+ 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;
+
+ ccmp_hdr2pn(pn, skb->data + hdrlen);
+
+ queue = ieee80211_is_mgmt(hdr->frame_control) ?
+ NUM_RX_DATA_QUEUES : rx->queue;
+
+ 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)) {
+ /* hardware didn't decrypt/verify MIC */
+ ccmp_special_blocks(skb, pn, key->u.ccmp.rx_crypto_buf, 1);
+
+ if (ieee80211_aes_ccm_decrypt(
+ key->u.ccmp.tfm, key->u.ccmp.rx_crypto_buf,
+ 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 */
+ skb_trim(skb, skb->len - CCMP_MIC_LEN);
+ 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_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 = tx->skb;
+ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+ struct ieee80211_key *key = tx->key;
+ struct ieee80211_mmie *mmie;
+ u8 *pn, aad[20];
+ int i;
+
+ if (info->control.hw_key)
+ return 0;
+
+ 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 */
+ pn = key->u.aes_cmac.tx_pn;
+
+ for (i = sizeof(key->u.aes_cmac.tx_pn) - 1; i >= 0; i--) {
+ pn[i]++;
+ if (pn[i])
+ break;
+ }
+ bip_ipn_swap(mmie->sequence_number, pn);
+
+ bip_aad(skb, aad);
+
+ /*
+ * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
+ */
+ ieee80211_aes_cmac(key->u.aes_cmac.tfm, key->u.aes_cmac.tx_crypto_buf,
+ 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;
+
+ 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,
+ key->u.aes_cmac.rx_crypto_buf, 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;
+}