[PATCH] ieee80211: Fix TKIP, repeated fragmentation problem, and payload_size reporting
tree 8428e9f510e6ad6c77baec89cb57374842abf733
parent d78bfd3ddae9c422dd350159110f9c4d7cfc50de
author Liu Hong <hong.liu@intel.com> 1124446520 -0500
committer James Ketrenos <jketreno@linux.intel.com> 1127313183 -0500
Fix TKIP, repeated fragmentation problem, and payload_size reporting
1. TKIP encryption
Originally, TKIP encryption issues msdu + mpdu encryption on every
fragment. Change the behavior to msdu encryption on the whole
packet, then mpdu encryption on every fragment.
2. Avoid repeated fragmentation when !host_encrypt.
We only need do fragmentation when using host encryption. Otherwise
we only need pass the whole packet to driver, letting driver do the
fragmentation.
3. change the txb->payload_size to correct value
FW will use this value to determine whether to do fragmentation. If
we pass the wrong value, fw may cut on the wrong bound which will
make decryption fail when we do host encryption.
NOTE: This requires changing drivers (hostap) that have
extra_prefix_len used within them (structure member name change).
Signed-off-by: Hong Liu <liu.hong@intel.com>
Signed-off-by: James Ketrenos <jketreno@linux.intel.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
diff --git a/include/net/ieee80211.h b/include/net/ieee80211.h
index 43cf2e5..46466f5 100644
--- a/include/net/ieee80211.h
+++ b/include/net/ieee80211.h
@@ -724,7 +724,9 @@
/* If the host performs {en,de}cryption, then set to 1 */
int host_encrypt;
+ int host_encrypt_msdu;
int host_decrypt;
+ int host_open_frag;
int ieee802_1x; /* is IEEE 802.1X used */
/* WPA data */
diff --git a/include/net/ieee80211_crypt.h b/include/net/ieee80211_crypt.h
index 536e9a9..24e4912 100644
--- a/include/net/ieee80211_crypt.h
+++ b/include/net/ieee80211_crypt.h
@@ -63,7 +63,8 @@
* extra_postfix_len; encrypt need not use all this space, but
* the result must start at the beginning of the buffer and correct
* length must be returned */
- int extra_prefix_len, extra_postfix_len;
+ int extra_mpdu_prefix_len, extra_mpdu_postfix_len;
+ int extra_msdu_prefix_len, extra_msdu_postfix_len;
struct module *owner;
};
diff --git a/net/ieee80211/ieee80211_crypt.c b/net/ieee80211/ieee80211_crypt.c
index 60d3166..e26bcc9 100644
--- a/net/ieee80211/ieee80211_crypt.c
+++ b/net/ieee80211/ieee80211_crypt.c
@@ -221,8 +221,8 @@
.decrypt_msdu = NULL,
.set_key = NULL,
.get_key = NULL,
- .extra_prefix_len = 0,
- .extra_postfix_len = 0,
+ .extra_mpdu_prefix_len = 0,
+ .extra_mpdu_postfix_len = 0,
.owner = THIS_MODULE,
};
diff --git a/net/ieee80211/ieee80211_crypt_ccmp.c b/net/ieee80211/ieee80211_crypt_ccmp.c
index d3b5cde..a3dc571 100644
--- a/net/ieee80211/ieee80211_crypt_ccmp.c
+++ b/net/ieee80211/ieee80211_crypt_ccmp.c
@@ -436,8 +436,8 @@
.set_key = ieee80211_ccmp_set_key,
.get_key = ieee80211_ccmp_get_key,
.print_stats = ieee80211_ccmp_print_stats,
- .extra_prefix_len = CCMP_HDR_LEN,
- .extra_postfix_len = CCMP_MIC_LEN,
+ .extra_mpdu_prefix_len = CCMP_HDR_LEN,
+ .extra_mpdu_postfix_len = CCMP_MIC_LEN,
.owner = THIS_MODULE,
};
diff --git a/net/ieee80211/ieee80211_crypt_tkip.c b/net/ieee80211/ieee80211_crypt_tkip.c
index f091aac..f973d6c 100644
--- a/net/ieee80211/ieee80211_crypt_tkip.c
+++ b/net/ieee80211/ieee80211_crypt_tkip.c
@@ -690,8 +690,9 @@
.set_key = ieee80211_tkip_set_key,
.get_key = ieee80211_tkip_get_key,
.print_stats = ieee80211_tkip_print_stats,
- .extra_prefix_len = 4 + 4, /* IV + ExtIV */
- .extra_postfix_len = 8 + 4, /* MIC + ICV */
+ .extra_mpdu_prefix_len = 4 + 4, /* IV + ExtIV */
+ .extra_mpdu_postfix_len = 4, /* ICV */
+ .extra_msdu_postfix_len = 8, /* MIC */
.owner = THIS_MODULE,
};
diff --git a/net/ieee80211/ieee80211_crypt_wep.c b/net/ieee80211/ieee80211_crypt_wep.c
index 63e783f..2aaeac1 100644
--- a/net/ieee80211/ieee80211_crypt_wep.c
+++ b/net/ieee80211/ieee80211_crypt_wep.c
@@ -239,8 +239,8 @@
.set_key = prism2_wep_set_key,
.get_key = prism2_wep_get_key,
.print_stats = prism2_wep_print_stats,
- .extra_prefix_len = 4, /* IV */
- .extra_postfix_len = 4, /* ICV */
+ .extra_mpdu_prefix_len = 4, /* IV */
+ .extra_mpdu_postfix_len = 4, /* ICV */
.owner = THIS_MODULE,
};
diff --git a/net/ieee80211/ieee80211_module.c b/net/ieee80211/ieee80211_module.c
index 67d6bdd..dddc616 100644
--- a/net/ieee80211/ieee80211_module.c
+++ b/net/ieee80211/ieee80211_module.c
@@ -133,6 +133,12 @@
/* Default to enabling full open WEP with host based encrypt/decrypt */
ieee->host_encrypt = 1;
ieee->host_decrypt = 1;
+ /* Host fragementation in Open mode. Default is enabled.
+ * Note: host fragmentation is always enabled if host encryption
+ * is enabled. For cards can do hardware encryption, they must do
+ * hardware fragmentation as well. So we don't need a variable
+ * like host_enc_frag. */
+ ieee->host_open_frag = 1;
ieee->ieee802_1x = 1; /* Default to supporting 802.1x */
INIT_LIST_HEAD(&ieee->crypt_deinit_list);
@@ -147,7 +153,6 @@
ieee->tkip_countermeasures = 0;
ieee->drop_unencrypted = 0;
ieee->privacy_invoked = 0;
- ieee->ieee802_1x = 1;
return dev;
diff --git a/net/ieee80211/ieee80211_tx.c b/net/ieee80211/ieee80211_tx.c
index f505aa1..23a1f88 100644
--- a/net/ieee80211/ieee80211_tx.c
+++ b/net/ieee80211/ieee80211_tx.c
@@ -128,7 +128,7 @@
static u8 P802_1H_OUI[P80211_OUI_LEN] = { 0x00, 0x00, 0xf8 };
static u8 RFC1042_OUI[P80211_OUI_LEN] = { 0x00, 0x00, 0x00 };
-static inline int ieee80211_put_snap(u8 * data, u16 h_proto)
+static inline int ieee80211_copy_snap(u8 * data, u16 h_proto)
{
struct ieee80211_snap_hdr *snap;
u8 *oui;
@@ -159,15 +159,9 @@
/* To encrypt, frame format is:
* IV (4 bytes), clear payload (including SNAP), ICV (4 bytes) */
-
- // PR: FIXME: Copied from hostap. Check fragmentation/MSDU/MPDU encryption.
- /* Host-based IEEE 802.11 fragmentation for TX is not yet supported, so
- * call both MSDU and MPDU encryption functions from here. */
atomic_inc(&crypt->refcnt);
res = 0;
- if (crypt->ops->encrypt_msdu)
- res = crypt->ops->encrypt_msdu(frag, hdr_len, crypt->priv);
- if (res == 0 && crypt->ops->encrypt_mpdu)
+ if (crypt->ops->encrypt_mpdu)
res = crypt->ops->encrypt_mpdu(frag, hdr_len, crypt->priv);
atomic_dec(&crypt->refcnt);
@@ -222,7 +216,7 @@
return txb;
}
-/* Incoming skb is converted to a txb which consist of
+/* Incoming skb is converted to a txb which consists of
* a block of 802.11 fragment packets (stored as skbs) */
int ieee80211_xmit(struct sk_buff *skb, struct net_device *dev)
{
@@ -233,7 +227,7 @@
rts_required;
unsigned long flags;
struct net_device_stats *stats = &ieee->stats;
- int ether_type, encrypt, host_encrypt;
+ int ether_type, encrypt, host_encrypt, host_encrypt_msdu;
int bytes, fc, hdr_len;
struct sk_buff *skb_frag;
struct ieee80211_hdr_3addr header = { /* Ensure zero initialized */
@@ -241,8 +235,8 @@
.seq_ctl = 0
};
u8 dest[ETH_ALEN], src[ETH_ALEN];
-
struct ieee80211_crypt_data *crypt;
+ int snapped = 0;
spin_lock_irqsave(&ieee->lock, flags);
@@ -266,6 +260,7 @@
encrypt = !(ether_type == ETH_P_PAE && ieee->ieee802_1x) &&
ieee->sec.encrypt;
host_encrypt = ieee->host_encrypt && encrypt;
+ host_encrypt_msdu = ieee->host_encrypt_msdu && encrypt;
if (!encrypt && ieee->ieee802_1x &&
ieee->drop_unencrypted && ether_type != ETH_P_PAE) {
@@ -291,14 +286,12 @@
if (ieee->iw_mode == IW_MODE_INFRA) {
fc |= IEEE80211_FCTL_TODS;
- /* To DS: Addr1 = BSSID, Addr2 = SA,
- Addr3 = DA */
+ /* To DS: Addr1 = BSSID, Addr2 = SA, Addr3 = DA */
memcpy(header.addr1, ieee->bssid, ETH_ALEN);
memcpy(header.addr2, src, ETH_ALEN);
memcpy(header.addr3, dest, ETH_ALEN);
} else if (ieee->iw_mode == IW_MODE_ADHOC) {
- /* not From/To DS: Addr1 = DA, Addr2 = SA,
- Addr3 = BSSID */
+ /* not From/To DS: Addr1 = DA, Addr2 = SA, Addr3 = BSSID */
memcpy(header.addr1, dest, ETH_ALEN);
memcpy(header.addr2, src, ETH_ALEN);
memcpy(header.addr3, ieee->bssid, ETH_ALEN);
@@ -306,42 +299,75 @@
header.frame_ctl = cpu_to_le16(fc);
hdr_len = IEEE80211_3ADDR_LEN;
- /* Determine fragmentation size based on destination (multicast
- * and broadcast are not fragmented) */
- if (is_multicast_ether_addr(dest) || is_broadcast_ether_addr(dest))
- frag_size = MAX_FRAG_THRESHOLD;
- else
- frag_size = ieee->fts;
+ /* Encrypt msdu first on the whole data packet. */
+ if ((host_encrypt || host_encrypt_msdu) &&
+ crypt && crypt->ops && crypt->ops->encrypt_msdu) {
+ int res = 0;
+ int len = bytes + hdr_len + crypt->ops->extra_msdu_prefix_len +
+ crypt->ops->extra_msdu_postfix_len;
+ struct sk_buff *skb_new = dev_alloc_skb(len);
+ if (unlikely(!skb_new))
+ goto failed;
+ skb_reserve(skb_new, crypt->ops->extra_msdu_prefix_len);
+ memcpy(skb_put(skb_new, hdr_len), &header, hdr_len);
+ snapped = 1;
+ ieee80211_copy_snap(skb_put(skb_new, SNAP_SIZE + sizeof(u16)),
+ ether_type);
+ memcpy(skb_put(skb_new, skb->len), skb->data, skb->len);
+ res = crypt->ops->encrypt_msdu(skb_new, hdr_len, crypt->priv);
+ if (res < 0) {
+ IEEE80211_ERROR("msdu encryption failed\n");
+ dev_kfree_skb_any(skb_new);
+ goto failed;
+ }
+ dev_kfree_skb_any(skb);
+ skb = skb_new;
+ bytes += crypt->ops->extra_msdu_prefix_len +
+ crypt->ops->extra_msdu_postfix_len;
+ skb_pull(skb, hdr_len);
+ }
- /* Determine amount of payload per fragment. Regardless of if
- * this stack is providing the full 802.11 header, one will
- * eventually be affixed to this fragment -- so we must account for
- * it when determining the amount of payload space. */
- bytes_per_frag = frag_size - IEEE80211_3ADDR_LEN;
- if (ieee->config &
- (CFG_IEEE80211_COMPUTE_FCS | CFG_IEEE80211_RESERVE_FCS))
- bytes_per_frag -= IEEE80211_FCS_LEN;
+ if (host_encrypt || ieee->host_open_frag) {
+ /* Determine fragmentation size based on destination (multicast
+ * and broadcast are not fragmented) */
+ if (is_multicast_ether_addr(dest))
+ frag_size = MAX_FRAG_THRESHOLD;
+ else
+ frag_size = ieee->fts;
- /* Each fragment may need to have room for encryptiong pre/postfix */
- if (host_encrypt)
- bytes_per_frag -= crypt->ops->extra_prefix_len +
- crypt->ops->extra_postfix_len;
+ /* Determine amount of payload per fragment. Regardless of if
+ * this stack is providing the full 802.11 header, one will
+ * eventually be affixed to this fragment -- so we must account
+ * for it when determining the amount of payload space. */
+ bytes_per_frag = frag_size - IEEE80211_3ADDR_LEN;
+ if (ieee->config &
+ (CFG_IEEE80211_COMPUTE_FCS | CFG_IEEE80211_RESERVE_FCS))
+ bytes_per_frag -= IEEE80211_FCS_LEN;
- /* Number of fragments is the total bytes_per_frag /
- * payload_per_fragment */
- nr_frags = bytes / bytes_per_frag;
- bytes_last_frag = bytes % bytes_per_frag;
- if (bytes_last_frag)
- nr_frags++;
- else
- bytes_last_frag = bytes_per_frag;
+ /* Each fragment may need to have room for encryptiong
+ * pre/postfix */
+ if (host_encrypt)
+ bytes_per_frag -= crypt->ops->extra_mpdu_prefix_len +
+ crypt->ops->extra_mpdu_postfix_len;
+
+ /* Number of fragments is the total
+ * bytes_per_frag / payload_per_fragment */
+ nr_frags = bytes / bytes_per_frag;
+ bytes_last_frag = bytes % bytes_per_frag;
+ if (bytes_last_frag)
+ nr_frags++;
+ else
+ bytes_last_frag = bytes_per_frag;
+ } else {
+ nr_frags = 1;
+ bytes_per_frag = bytes_last_frag = bytes;
+ frag_size = bytes + IEEE80211_3ADDR_LEN;
+ }
rts_required = (frag_size > ieee->rts
&& ieee->config & CFG_IEEE80211_RTS);
if (rts_required)
nr_frags++;
- else
- bytes_last_frag = bytes_per_frag;
/* When we allocate the TXB we allocate enough space for the reserve
* and full fragment bytes (bytes_per_frag doesn't include prefix,
@@ -353,7 +379,11 @@
goto failed;
}
txb->encrypted = encrypt;
- txb->payload_size = bytes;
+ if (host_encrypt)
+ txb->payload_size = frag_size * (nr_frags - 1) +
+ bytes_last_frag;
+ else
+ txb->payload_size = bytes;
if (rts_required) {
skb_frag = txb->fragments[0];
@@ -385,7 +415,8 @@
skb_frag = txb->fragments[i];
if (host_encrypt)
- skb_reserve(skb_frag, crypt->ops->extra_prefix_len);
+ skb_reserve(skb_frag,
+ crypt->ops->extra_mpdu_prefix_len);
frag_hdr =
(struct ieee80211_hdr_3addr *)skb_put(skb_frag, hdr_len);
@@ -402,11 +433,10 @@
bytes = bytes_last_frag;
}
- /* Put a SNAP header on the first fragment */
- if (i == 0) {
- ieee80211_put_snap(skb_put
- (skb_frag, SNAP_SIZE + sizeof(u16)),
- ether_type);
+ if (i == 0 && !snapped) {
+ ieee80211_copy_snap(skb_put
+ (skb_frag, SNAP_SIZE + sizeof(u16)),
+ ether_type);
bytes -= SNAP_SIZE + sizeof(u16);
}
@@ -420,19 +450,6 @@
if (host_encrypt)
ieee80211_encrypt_fragment(ieee, skb_frag, hdr_len);
- /* ipw2200/2915 Hardware encryption doesn't support TKIP MIC */
- if (!ieee->host_encrypt && encrypt &&
- (ieee->sec.level == SEC_LEVEL_2) &&
- crypt && crypt->ops && crypt->ops->encrypt_msdu) {
- int res = 0;
- res = crypt->ops->encrypt_msdu(skb_frag, hdr_len,
- crypt->priv);
- if (res < 0) {
- IEEE80211_ERROR("TKIP MIC encryption failed\n");
- goto failed;
- }
- }
-
if (ieee->config &
(CFG_IEEE80211_COMPUTE_FCS | CFG_IEEE80211_RESERVE_FCS))
skb_put(skb_frag, 4);
@@ -444,7 +461,8 @@
dev_kfree_skb_any(skb);
if (txb) {
- if ((*ieee->hard_start_xmit) (txb, dev) == 0) {
+ int ret = (*ieee->hard_start_xmit) (txb, dev);
+ if (ret == 0) {
stats->tx_packets++;
stats->tx_bytes += txb->payload_size;
return 0;