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-rw-r--r--net/mac80211/wpa.c152
1 files changed, 144 insertions, 8 deletions
diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c
index 7aa63caf8d50..9101b48ec2ae 100644
--- a/net/mac80211/wpa.c
+++ b/net/mac80211/wpa.c
@@ -1,5 +1,6 @@
/*
* 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
@@ -19,6 +20,7 @@
#include "michael.h"
#include "tkip.h"
#include "aes_ccm.h"
+#include "aes_cmac.h"
#include "wpa.h"
ieee80211_tx_result
@@ -266,7 +268,7 @@ static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *scratch,
int encrypted)
{
__le16 mask_fc;
- int a4_included;
+ int a4_included, mgmt;
u8 qos_tid;
u8 *b_0, *aad;
u16 data_len, len_a;
@@ -277,12 +279,15 @@ static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *scratch,
aad = scratch + 4 * AES_BLOCK_LEN;
/*
- * Mask FC: zero subtype b4 b5 b6
+ * 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(0x0070 | IEEE80211_FCTL_RETRY |
+ 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);
@@ -300,8 +305,10 @@ static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *scratch,
/* First block, b_0 */
b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */
- /* Nonce: QoS Priority | A2 | PN */
- b_0[1] = qos_tid;
+ /* 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) */
@@ -360,9 +367,14 @@ static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
int hdrlen, len, tail;
u8 *pos, *pn;
int i;
+ bool skip_hw;
+
+ skip_hw = (tx->key->conf.flags & IEEE80211_KEY_FLAG_SW_MGMT) &&
+ ieee80211_is_mgmt(hdr->frame_control);
if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
- !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV)) {
+ !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
+ !skip_hw) {
/* hwaccel - with no need for preallocated room for CCMP
* header or MIC fields */
info->control.hw_key = &tx->key->conf;
@@ -397,7 +409,7 @@ static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
ccmp_pn2hdr(pos, pn, key->conf.keyidx);
- if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
+ if ((key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) && !skip_hw) {
/* hwaccel - with preallocated room for CCMP header */
info->control.hw_key = &tx->key->conf;
return 0;
@@ -446,7 +458,8 @@ ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx)
hdrlen = ieee80211_hdrlen(hdr->frame_control);
- if (!ieee80211_is_data(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;
@@ -485,3 +498,126 @@ ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx)
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 (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
+ /* hwaccel */
+ info->control.hw_key = &tx->key->conf;
+ 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_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 ((rx->status->flag & RX_FLAG_DECRYPTED) &&
+ (rx->status->flag & RX_FLAG_IV_STRIPPED))
+ 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 (!(rx->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;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-26 10:32:21 +0100