Split crypto tx+rx key indices and add a key index -> node mapping table:

Crypto changes:
o change driver/net80211 key_alloc api to return tx+rx key indices; a
  driver can leave the rx key index set to IEEE80211_KEYIX_NONE or set
  it to be the same as the tx key index (the former disables use of
  the key index in building the keyix->node mapping table and is the
  default setup for naive drivers by null_key_alloc)
o add cs_max_keyid to crypto state to specify the max h/w key index a
  driver will return; this is used to allocate the key index mapping
  table and to bounds check table loookups
o while here introduce ieee80211_keyix (finally) for the type of a h/w
  key index
o change crypto notifiers for rx failures to pass the rx key index up
  as appropriate (michael failure, replay, etc.)

Node table changes:
o optionally allocate a h/w key index to node mapping table for the
  station table using the max key index setting supplied by drivers
  (note the scan table does not get a map)
o defer node table allocation to lateattach so the driver has a chance
  to set the max key id to size the key index map
o while here also defer the aid bitmap allocation
o add new ieee80211_find_rxnode_withkey api to find a sta/node entry
  on frame receive with an optional h/w key index to use in checking
  mapping table; also updates the map if it does a hash lookup and the
  found node has a rx key index set in the unicast key; note this work
  is separated from the old ieee80211_find_rxnode call so drivers do
  not need to be aware of the new mechanism
o move some node table manipulation under the node table lock to close
  a race on node delete
o add ieee80211_node_delucastkey to do the dirty work of deleting
  unicast key state for a node (deletes any key and handles key map
  references)

Ath driver:
o nuke private sc_keyixmap mechansim in favor of net80211 support
o update key alloc api

These changes close several race conditions for the ath driver operating
in ap mode.  Other drivers should see no change.  Station mode operation
for ath no longer uses the key index map but performance tests show no
noticeable change and this will be fixed when the scan table is eliminated
with the new scanning support.

Tested by:	Michal Mertl, avatar, others
Reviewed by:	avatar, others
MFC after:	2 weeks

1 files changed, 13 insertions, 10 deletions

diff --git a/sys/net80211/ieee80211_crypto.h b/sys/net80211/ieee80211_crypto.h
index 19b6dcd..f006a7a 100644
--- a/sys/net80211/ieee80211_crypto.h
+++ b/sys/net80211/ieee80211_crypto.h
@@ -66,18 +66,19 @@ struct ieee80211_cipher;
  * Ciphers such as TKIP may also support mixed hardware/software
  * encrypt/decrypt and MIC processing.
  */
-/* XXX need key index typedef */
-/* XXX pack better? */
-/* XXX 48-bit rsc/tsc */
+typedef u_int16_t ieee80211_keyix;	/* h/w key index */
+
 struct ieee80211_key {
 	u_int8_t	wk_keylen;	/* key length in bytes */
-	u_int8_t	wk_flags;
+	u_int8_t	wk_pad;
+	u_int16_t	wk_flags;
 #define	IEEE80211_KEY_XMIT	0x01	/* key used for xmit */
 #define	IEEE80211_KEY_RECV	0x02	/* key used for recv */
 #define	IEEE80211_KEY_GROUP	0x04	/* key used for WPA group operation */
 #define	IEEE80211_KEY_SWCRYPT	0x10	/* host-based encrypt/decrypt */
 #define	IEEE80211_KEY_SWMIC	0x20	/* host-based enmic/demic */
-	u_int16_t	wk_keyix;	/* key index */
+	ieee80211_keyix	wk_keyix;	/* h/w key index */
+	ieee80211_keyix	wk_rxkeyix;	/* optional h/w rx key index */
 	u_int8_t	wk_key[IEEE80211_KEYBUF_SIZE+IEEE80211_MICBUF_SIZE];
 #define	wk_txmic	wk_key+IEEE80211_KEYBUF_SIZE+0	/* XXX can't () right */
 #define	wk_rxmic	wk_key+IEEE80211_KEYBUF_SIZE+8	/* XXX can't () right */
@@ -103,7 +104,7 @@ struct ieee80211_key {
 
 #define	IEEE80211_CIPHER_MAX		(IEEE80211_CIPHER_NONE+1)
 
-#define	IEEE80211_KEYIX_NONE	((u_int16_t) -1)
+#define	IEEE80211_KEYIX_NONE	((ieee80211_keyix) -1)
 
 #if defined(__KERNEL__) || defined(_KERNEL)
 
@@ -120,10 +121,12 @@ struct mbuf;
  */
 struct ieee80211_crypto_state {
 	struct ieee80211_key	cs_nw_keys[IEEE80211_WEP_NKID];
-	u_int16_t		cs_def_txkey;	/* default/group tx key index */
+	ieee80211_keyix		cs_def_txkey;	/* default/group tx key index */
+	u_int16_t		cs_max_keyix;	/* max h/w key index */
 
 	int			(*cs_key_alloc)(struct ieee80211com *,
-					const struct ieee80211_key *);
+					const struct ieee80211_key *,
+					ieee80211_keyix *, ieee80211_keyix *);
 	int			(*cs_key_delete)(struct ieee80211com *, 
 					const struct ieee80211_key *);
 	int			(*cs_key_set)(struct ieee80211com *,
@@ -204,11 +207,11 @@ ieee80211_crypto_enmic(struct ieee80211com *ic,
  */
 static __inline void
 ieee80211_crypto_resetkey(struct ieee80211com *ic,
-	struct ieee80211_key *k, u_int16_t ix)
+	struct ieee80211_key *k, ieee80211_keyix ix)
 {
 	k->wk_cipher = &ieee80211_cipher_none;;
 	k->wk_private = k->wk_cipher->ic_attach(ic, k);
-	k->wk_keyix = ix;
+	k->wk_keyix = k->wk_rxkeyix = ix;
 	k->wk_flags = IEEE80211_KEY_XMIT | IEEE80211_KEY_RECV;
 }