[PATCH 4.4 09/56] ath10k: rebuild crypto header in rx data frames

From: Greg Kroah-Hartman
Date: Mon May 14 2018 - 02:52:18 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Vasanthakumar Thiagarajan <vthiagar@xxxxxxxxxxxxxxxx>

commit 7eccb738fce57cbe53ed903ccf43f9ab257b15b3 upstream.

Rx data frames notified through HTT_T2H_MSG_TYPE_RX_IND and
HTT_T2H_MSG_TYPE_RX_FRAG_IND expect PN/TSC check to be done
on host (mac80211) rather than firmware. Rebuild cipher header
in every received data frames (that are notified through those
HTT interfaces) from the rx_hdr_status tlv available in the
rx descriptor of the first msdu. Skip setting RX_FLAG_IV_STRIPPED
flag for the packets which requires mac80211 PN/TSC check support
and set appropriate RX_FLAG for stripped crypto tail. Hw QCA988X,
QCA9887, QCA99X0, QCA9984, QCA9888 and QCA4019 currently need the
rebuilding of cipher header to perform PN/TSC check for replay
attack.

Please note that removing crypto tail for CCMP-256, GCMP and GCMP-256 ciphers
in raw mode needs to be fixed. Since Rx with these ciphers in raw
mode does not work in the current form even without this patch and
removing crypto tail for these chipers needs clean up, raw mode related
issues in CCMP-256, GCMP and GCMP-256 can be addressed in follow up
patches.

Tested-by: Manikanta Pubbisetty <mpubbise@xxxxxxxxxxxxxxxx>
Signed-off-by: Vasanthakumar Thiagarajan <vthiagar@xxxxxxxxxxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxxxx>
Signed-off-by: Sriram R <srirrama@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/wireless/ath/ath10k/htt_rx.c | 98 +++++++++++++++++++++++++------
1 file changed, 82 insertions(+), 16 deletions(-)

--- a/drivers/net/wireless/ath/ath10k/htt_rx.c
+++ b/drivers/net/wireless/ath/ath10k/htt_rx.c
@@ -1076,7 +1076,21 @@ static void ath10k_htt_rx_h_undecap_raw(
hdr = (void *)msdu->data;

/* Tail */
- skb_trim(msdu, msdu->len - ath10k_htt_rx_crypto_tail_len(ar, enctype));
+ if (status->flag & RX_FLAG_IV_STRIPPED) {
+ skb_trim(msdu, msdu->len -
+ ath10k_htt_rx_crypto_tail_len(ar, enctype));
+ } else {
+ /* MIC */
+ if ((status->flag & RX_FLAG_MIC_STRIPPED) &&
+ enctype == HTT_RX_MPDU_ENCRYPT_AES_CCM_WPA2)
+ skb_trim(msdu, msdu->len - 8);
+
+ /* ICV */
+ if (status->flag & RX_FLAG_ICV_STRIPPED &&
+ enctype != HTT_RX_MPDU_ENCRYPT_AES_CCM_WPA2)
+ skb_trim(msdu, msdu->len -
+ ath10k_htt_rx_crypto_tail_len(ar, enctype));
+ }

/* MMIC */
if (!ieee80211_has_morefrags(hdr->frame_control) &&
@@ -1095,12 +1109,14 @@ static void ath10k_htt_rx_h_undecap_raw(
static void ath10k_htt_rx_h_undecap_nwifi(struct ath10k *ar,
struct sk_buff *msdu,
struct ieee80211_rx_status *status,
- const u8 first_hdr[64])
+ const u8 first_hdr[64],
+ enum htt_rx_mpdu_encrypt_type enctype)
{
struct ieee80211_hdr *hdr;
size_t hdr_len;
u8 da[ETH_ALEN];
u8 sa[ETH_ALEN];
+ int bytes_aligned = ar->hw_params.decap_align_bytes;

/* Delivered decapped frame:
* [nwifi 802.11 header] <-- replaced with 802.11 hdr
@@ -1123,6 +1139,14 @@ static void ath10k_htt_rx_h_undecap_nwif
/* push original 802.11 header */
hdr = (struct ieee80211_hdr *)first_hdr;
hdr_len = ieee80211_hdrlen(hdr->frame_control);
+
+ if (!(status->flag & RX_FLAG_IV_STRIPPED)) {
+ memcpy(skb_push(msdu,
+ ath10k_htt_rx_crypto_param_len(ar, enctype)),
+ (void *)hdr + round_up(hdr_len, bytes_aligned),
+ ath10k_htt_rx_crypto_param_len(ar, enctype));
+ }
+
memcpy(skb_push(msdu, hdr_len), hdr, hdr_len);

/* original 802.11 header has a different DA and in
@@ -1180,6 +1204,7 @@ static void ath10k_htt_rx_h_undecap_eth(
void *rfc1042;
u8 da[ETH_ALEN];
u8 sa[ETH_ALEN];
+ int bytes_aligned = ar->hw_params.decap_align_bytes;

/* Delivered decapped frame:
* [eth header] <-- replaced with 802.11 hdr & rfc1042/llc
@@ -1203,6 +1228,14 @@ static void ath10k_htt_rx_h_undecap_eth(
/* push original 802.11 header */
hdr = (struct ieee80211_hdr *)first_hdr;
hdr_len = ieee80211_hdrlen(hdr->frame_control);
+
+ if (!(status->flag & RX_FLAG_IV_STRIPPED)) {
+ memcpy(skb_push(msdu,
+ ath10k_htt_rx_crypto_param_len(ar, enctype)),
+ (void *)hdr + round_up(hdr_len, bytes_aligned),
+ ath10k_htt_rx_crypto_param_len(ar, enctype));
+ }
+
memcpy(skb_push(msdu, hdr_len), hdr, hdr_len);

/* original 802.11 header has a different DA and in
@@ -1216,10 +1249,12 @@ static void ath10k_htt_rx_h_undecap_eth(
static void ath10k_htt_rx_h_undecap_snap(struct ath10k *ar,
struct sk_buff *msdu,
struct ieee80211_rx_status *status,
- const u8 first_hdr[64])
+ const u8 first_hdr[64],
+ enum htt_rx_mpdu_encrypt_type enctype)
{
struct ieee80211_hdr *hdr;
size_t hdr_len;
+ int bytes_aligned = ar->hw_params.decap_align_bytes;

/* Delivered decapped frame:
* [amsdu header] <-- replaced with 802.11 hdr
@@ -1231,6 +1266,14 @@ static void ath10k_htt_rx_h_undecap_snap

hdr = (struct ieee80211_hdr *)first_hdr;
hdr_len = ieee80211_hdrlen(hdr->frame_control);
+
+ if (!(status->flag & RX_FLAG_IV_STRIPPED)) {
+ memcpy(skb_push(msdu,
+ ath10k_htt_rx_crypto_param_len(ar, enctype)),
+ (void *)hdr + round_up(hdr_len, bytes_aligned),
+ ath10k_htt_rx_crypto_param_len(ar, enctype));
+ }
+
memcpy(skb_push(msdu, hdr_len), hdr, hdr_len);
}

@@ -1265,13 +1308,15 @@ static void ath10k_htt_rx_h_undecap(stru
is_decrypted);
break;
case RX_MSDU_DECAP_NATIVE_WIFI:
- ath10k_htt_rx_h_undecap_nwifi(ar, msdu, status, first_hdr);
+ ath10k_htt_rx_h_undecap_nwifi(ar, msdu, status, first_hdr,
+ enctype);
break;
case RX_MSDU_DECAP_ETHERNET2_DIX:
ath10k_htt_rx_h_undecap_eth(ar, msdu, status, first_hdr, enctype);
break;
case RX_MSDU_DECAP_8023_SNAP_LLC:
- ath10k_htt_rx_h_undecap_snap(ar, msdu, status, first_hdr);
+ ath10k_htt_rx_h_undecap_snap(ar, msdu, status, first_hdr,
+ enctype);
break;
}
}
@@ -1314,7 +1359,8 @@ static void ath10k_htt_rx_h_csum_offload

static void ath10k_htt_rx_h_mpdu(struct ath10k *ar,
struct sk_buff_head *amsdu,
- struct ieee80211_rx_status *status)
+ struct ieee80211_rx_status *status,
+ bool fill_crypt_header)
{
struct sk_buff *first;
struct sk_buff *last;
@@ -1324,7 +1370,6 @@ static void ath10k_htt_rx_h_mpdu(struct
enum htt_rx_mpdu_encrypt_type enctype;
u8 first_hdr[64];
u8 *qos;
- size_t hdr_len;
bool has_fcs_err;
bool has_crypto_err;
bool has_tkip_err;
@@ -1345,15 +1390,17 @@ static void ath10k_htt_rx_h_mpdu(struct
* decapped header. It'll be used for undecapping of each MSDU.
*/
hdr = (void *)rxd->rx_hdr_status;
- hdr_len = ieee80211_hdrlen(hdr->frame_control);
- memcpy(first_hdr, hdr, hdr_len);
+ memcpy(first_hdr, hdr, RX_HTT_HDR_STATUS_LEN);

/* Each A-MSDU subframe will use the original header as the base and be
* reported as a separate MSDU so strip the A-MSDU bit from QoS Ctl.
*/
hdr = (void *)first_hdr;
- qos = ieee80211_get_qos_ctl(hdr);
- qos[0] &= ~IEEE80211_QOS_CTL_A_MSDU_PRESENT;
+
+ if (ieee80211_is_data_qos(hdr->frame_control)) {
+ qos = ieee80211_get_qos_ctl(hdr);
+ qos[0] &= ~IEEE80211_QOS_CTL_A_MSDU_PRESENT;
+ }

/* Some attention flags are valid only in the last MSDU. */
last = skb_peek_tail(amsdu);
@@ -1387,11 +1434,17 @@ static void ath10k_htt_rx_h_mpdu(struct
if (has_tkip_err)
status->flag |= RX_FLAG_MMIC_ERROR;

- if (is_decrypted)
+ if (is_decrypted) {
status->flag |= RX_FLAG_DECRYPTED |
- RX_FLAG_IV_STRIPPED |
RX_FLAG_MMIC_STRIPPED;

+ if (fill_crypt_header)
+ status->flag |= RX_FLAG_MIC_STRIPPED |
+ RX_FLAG_ICV_STRIPPED;
+ else
+ status->flag |= RX_FLAG_IV_STRIPPED;
+ }
+
skb_queue_walk(amsdu, msdu) {
ath10k_htt_rx_h_csum_offload(msdu);
ath10k_htt_rx_h_undecap(ar, msdu, status, first_hdr, enctype,
@@ -1404,6 +1457,9 @@ static void ath10k_htt_rx_h_mpdu(struct
if (!is_decrypted)
continue;

+ if (fill_crypt_header)
+ continue;
+
hdr = (void *)msdu->data;
hdr->frame_control &= ~__cpu_to_le16(IEEE80211_FCTL_PROTECTED);
}
@@ -1414,6 +1470,9 @@ static void ath10k_htt_rx_h_deliver(stru
struct ieee80211_rx_status *status)
{
struct sk_buff *msdu;
+ struct sk_buff *first_subframe;
+
+ first_subframe = skb_peek(amsdu);

while ((msdu = __skb_dequeue(amsdu))) {
/* Setup per-MSDU flags */
@@ -1422,6 +1481,13 @@ static void ath10k_htt_rx_h_deliver(stru
else
status->flag |= RX_FLAG_AMSDU_MORE;

+ if (msdu == first_subframe) {
+ first_subframe = NULL;
+ status->flag &= ~RX_FLAG_ALLOW_SAME_PN;
+ } else {
+ status->flag |= RX_FLAG_ALLOW_SAME_PN;
+ }
+
ath10k_process_rx(ar, status, msdu);
}
}
@@ -1607,7 +1673,7 @@ static void ath10k_htt_rx_handler(struct
ath10k_htt_rx_h_ppdu(ar, &amsdu, rx_status, 0xffff);
ath10k_htt_rx_h_unchain(ar, &amsdu, ret > 0);
ath10k_htt_rx_h_filter(ar, &amsdu, rx_status);
- ath10k_htt_rx_h_mpdu(ar, &amsdu, rx_status);
+ ath10k_htt_rx_h_mpdu(ar, &amsdu, rx_status, true);
ath10k_htt_rx_h_deliver(ar, &amsdu, rx_status);
}

@@ -1653,7 +1719,7 @@ static void ath10k_htt_rx_frag_handler(s

ath10k_htt_rx_h_ppdu(ar, &amsdu, rx_status, 0xffff);
ath10k_htt_rx_h_filter(ar, &amsdu, rx_status);
- ath10k_htt_rx_h_mpdu(ar, &amsdu, rx_status);
+ ath10k_htt_rx_h_mpdu(ar, &amsdu, rx_status, true);
ath10k_htt_rx_h_deliver(ar, &amsdu, rx_status);

if (fw_desc_len > 0) {
@@ -1952,7 +2018,7 @@ static void ath10k_htt_rx_in_ord_ind(str
*/
ath10k_htt_rx_h_ppdu(ar, &amsdu, status, vdev_id);
ath10k_htt_rx_h_filter(ar, &amsdu, status);
- ath10k_htt_rx_h_mpdu(ar, &amsdu, status);
+ ath10k_htt_rx_h_mpdu(ar, &amsdu, status, false);
ath10k_htt_rx_h_deliver(ar, &amsdu, status);
break;
case -EAGAIN: