From: Chien Wong <m@xv97.com>
To: johannes@sipsolutions.net
Cc: linux-wireless@vger.kernel.org
Subject: [PATCH v3 5/5] wifi: mac80211: refactor CMAC packet handlers
Date: Tue, 11 Nov 2025 22:57:59 +0800 [thread overview]
Message-ID: <20251111145759.111691-6-m@xv97.com> (raw)
In-Reply-To: <20251111145759.111691-1-m@xv97.com>
Merge CMAC-128 and CMAC-256 handlers since they are almost the same.
This removes duplication.
All references to the refactored functions in the tree are adapted.
The comment 'MIC = AES-128-CMAC(IGTK, AAD ...' is out-dated since CMAC
is also used with BIGTK, as is the comment for CMAC-256. Simply remove
the comments.
Tested-on: mac80211_hwsim
Signed-off-by: Chien Wong <m@xv97.com>
---
net/mac80211/rx.c | 6 +-
net/mac80211/tx.c | 6 +-
net/mac80211/wpa.c | 144 ++++++++-------------------------------------
net/mac80211/wpa.h | 10 ++--
4 files changed, 35 insertions(+), 131 deletions(-)
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 80067ed1da2f..4c1b649b844a 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -2215,10 +2215,12 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
rx, IEEE80211_CCMP_256_MIC_LEN);
break;
case WLAN_CIPHER_SUITE_AES_CMAC:
- result = ieee80211_crypto_aes_cmac_decrypt(rx);
+ result = ieee80211_crypto_aes_cmac_decrypt(
+ rx, IEEE80211_CMAC_128_MIC_LEN);
break;
case WLAN_CIPHER_SUITE_BIP_CMAC_256:
- result = ieee80211_crypto_aes_cmac_256_decrypt(rx);
+ result = ieee80211_crypto_aes_cmac_decrypt(
+ rx, IEEE80211_CMAC_256_MIC_LEN);
break;
case WLAN_CIPHER_SUITE_BIP_GMAC_128:
case WLAN_CIPHER_SUITE_BIP_GMAC_256:
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index e7b141c55f7a..9d8b0a25f73c 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -1062,9 +1062,11 @@ ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx)
return ieee80211_crypto_ccmp_encrypt(
tx, IEEE80211_CCMP_256_MIC_LEN);
case WLAN_CIPHER_SUITE_AES_CMAC:
- return ieee80211_crypto_aes_cmac_encrypt(tx);
+ return ieee80211_crypto_aes_cmac_encrypt(
+ tx, IEEE80211_CMAC_128_MIC_LEN);
case WLAN_CIPHER_SUITE_BIP_CMAC_256:
- return ieee80211_crypto_aes_cmac_256_encrypt(tx);
+ return ieee80211_crypto_aes_cmac_encrypt(
+ tx, IEEE80211_CMAC_256_MIC_LEN);
case WLAN_CIPHER_SUITE_BIP_GMAC_128:
case WLAN_CIPHER_SUITE_BIP_GMAC_256:
return ieee80211_crypto_aes_gmac_encrypt(tx);
diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c
index 2c1ee4b8e205..2f8bd5216542 100644
--- a/net/mac80211/wpa.c
+++ b/net/mac80211/wpa.c
@@ -828,12 +828,14 @@ static inline void bip_ipn_swap(u8 *d, const u8 *s)
ieee80211_tx_result
-ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
+ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx,
+ unsigned int mic_len)
{
struct sk_buff *skb;
struct ieee80211_tx_info *info;
struct ieee80211_key *key = tx->key;
- struct ieee80211_mmie *mmie;
+ struct ieee80211_mmie_var *mmie;
+ size_t mmie_len;
u8 aad[20];
u64 pn64;
@@ -848,62 +850,14 @@ ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
!(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIE))
return TX_CONTINUE;
- if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
- return TX_DROP;
-
- 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);
+ mmie_len = sizeof(*mmie) + mic_len;
- /* PN = PN + 1 */
- pn64 = atomic64_inc_return(&key->conf.tx_pn);
-
- bip_ipn_set64(mmie->sequence_number, pn64);
-
- if (info->control.hw_key)
- return TX_CONTINUE;
-
- bip_aad(skb, aad);
-
- /*
- * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
- */
- if (ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
- skb->data + 24, skb->len - 24, mmie->mic,
- IEEE80211_CMAC_128_MIC_LEN))
+ if (WARN_ON(skb_tailroom(skb) < mmie_len))
return TX_DROP;
- return TX_CONTINUE;
-}
-
-ieee80211_tx_result
-ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx)
-{
- struct sk_buff *skb;
- struct ieee80211_tx_info *info;
- struct ieee80211_key *key = tx->key;
- struct ieee80211_mmie_16 *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 &&
- !(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIE))
- return TX_CONTINUE;
-
- if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
- return TX_DROP;
-
- mmie = skb_put(skb, sizeof(*mmie));
+ mmie = skb_put(skb, mmie_len);
mmie->element_id = WLAN_EID_MMIE;
- mmie->length = sizeof(*mmie) - 2;
+ mmie->length = mmie_len - 2;
mmie->key_id = cpu_to_le16(key->conf.keyidx);
/* PN = PN + 1 */
@@ -916,90 +870,39 @@ ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx)
bip_aad(skb, aad);
- /* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128)
- */
if (ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
- skb->data + 24, skb->len - 24, mmie->mic,
- IEEE80211_CMAC_256_MIC_LEN))
+ skb->data + 24, skb->len - 24, mmie->mic, mic_len))
return TX_DROP;
return TX_CONTINUE;
}
ieee80211_rx_result
-ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
+ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx,
+ unsigned int mic_len)
{
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_mmie_var *mmie;
+ size_t mmie_len;
+ u8 aad[20], mic[IEEE80211_CMAC_256_MIC_LEN], 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_U_SHORT_CMAC;
-
- 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_U_BAD_MMIE; /* 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_U_REPLAY;
- }
-
- if (!(status->flag & RX_FLAG_DECRYPTED)) {
- /* hardware didn't decrypt/verify MIC */
- bip_aad(skb, aad);
- if (ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
- skb->data + 24, skb->len - 24, mic,
- IEEE80211_CMAC_128_MIC_LEN))
- return RX_DROP_U_DECRYPT_FAIL;
- if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
- key->u.aes_cmac.icverrors++;
- return RX_DROP_U_MIC_FAIL;
- }
- }
-
- memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
-
- /* Remove MMIE */
- skb_trim(skb, skb->len - sizeof(*mmie));
-
- return RX_CONTINUE;
-}
-
-ieee80211_rx_result
-ieee80211_crypto_aes_cmac_256_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_16 *mmie;
- u8 aad[20], mic[16], ipn[6];
- struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
-
- if (!ieee80211_is_mgmt(hdr->frame_control))
- return RX_CONTINUE;
+ mmie_len = sizeof(*mmie) + mic_len;
/* management frames are already linear */
- if (skb->len < 24 + sizeof(*mmie))
- return RX_DROP_U_SHORT_CMAC256;
+ if (skb->len < 24 + mmie_len)
+ return mic_len == IEEE80211_CMAC_128_MIC_LEN ?
+ RX_DROP_U_SHORT_CMAC : RX_DROP_U_SHORT_CMAC256;
- mmie = (struct ieee80211_mmie_16 *)
- (skb->data + skb->len - sizeof(*mmie));
+ mmie = (struct ieee80211_mmie_var *)(skb->data + skb->len - mmie_len);
if (mmie->element_id != WLAN_EID_MMIE ||
- mmie->length != sizeof(*mmie) - 2)
+ mmie->length != mmie_len - 2)
return RX_DROP_U_BAD_MMIE; /* Invalid MMIE */
bip_ipn_swap(ipn, mmie->sequence_number);
@@ -1013,10 +916,9 @@ ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
/* hardware didn't decrypt/verify MIC */
bip_aad(skb, aad);
if (ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
- skb->data + 24, skb->len - 24, mic,
- IEEE80211_CMAC_256_MIC_LEN))
+ skb->data + 24, skb->len - 24, mic, mic_len))
return RX_DROP_U_DECRYPT_FAIL;
- if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
+ if (crypto_memneq(mic, mmie->mic, mic_len)) {
key->u.aes_cmac.icverrors++;
return RX_DROP_U_MIC_FAIL;
}
@@ -1025,7 +927,7 @@ ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
/* Remove MMIE */
- skb_trim(skb, skb->len - sizeof(*mmie));
+ skb_trim(skb, skb->len - mmie_len);
return RX_CONTINUE;
}
diff --git a/net/mac80211/wpa.h b/net/mac80211/wpa.h
index a9a81abb5479..6e8846dfe710 100644
--- a/net/mac80211/wpa.h
+++ b/net/mac80211/wpa.h
@@ -29,13 +29,11 @@ ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx,
unsigned int mic_len);
ieee80211_tx_result
-ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx);
-ieee80211_tx_result
-ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx);
-ieee80211_rx_result
-ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx);
+ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx,
+ unsigned int mic_len);
ieee80211_rx_result
-ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx);
+ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx,
+ unsigned int mic_len);
ieee80211_tx_result
ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx);
ieee80211_rx_result
--
2.51.2
prev parent reply other threads:[~2025-11-11 14:58 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-11-11 14:57 [PATCH v3 0/5] wifi: mac80211: refactor CMAC implementation Chien Wong
2025-11-11 14:57 ` [PATCH v3 1/5] wifi: mac80211: fix CMAC functions not handling errors Chien Wong
2025-11-12 13:11 ` Johannes Berg
2025-11-13 13:15 ` Chien Wong
2025-11-11 14:57 ` [PATCH v3 2/5] wifi: mac80211: add generic MMIE struct defines Chien Wong
2025-11-11 14:57 ` [PATCH v3 3/5] wifi: mac80211: utilize the newly defined CMAC constants Chien Wong
2025-11-12 13:12 ` Johannes Berg
2025-11-13 13:16 ` Chien Wong
2025-11-11 14:57 ` [PATCH v3 4/5] wifi: mac80211: refactor CMAC crypt functions Chien Wong
2025-11-12 13:19 ` Johannes Berg
2025-11-13 13:24 ` Chien Wong
2025-11-11 14:57 ` Chien Wong [this message]
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