mac80211: extend get_key() to return PN for all ciphers

For ciphers not supported by mac80211, the function currently
doesn't return any PN data. Fix this by extending the driver's
get_key_seq() a little more to allow moving arbitrary PN data.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 47b39c2..67e0df1 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1501,6 +1501,8 @@
 	u8 key[0];
 };
 
+#define IEEE80211_MAX_PN_LEN	16
+
 /**
  * struct ieee80211_key_seq - key sequence counter
  *
@@ -1513,6 +1515,7 @@
  *	reverse order than in packet)
  * @gcmp: PN data, most significant byte first (big endian,
  *	reverse order than in packet)
+ * @hw: data for HW-only (e.g. cipher scheme) keys
  */
 struct ieee80211_key_seq {
 	union {
@@ -1532,6 +1535,10 @@
 		struct {
 			u8 pn[6];
 		} gcmp;
+		struct {
+			u8 seq[IEEE80211_MAX_PN_LEN];
+			u8 seq_len;
+		} hw;
 	};
 };
 
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index dd7014b..3469bbd 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -431,6 +431,15 @@
 		params.seq = seq;
 		params.seq_len = 6;
 		break;
+	default:
+		if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
+			break;
+		if (WARN_ON(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV))
+			break;
+		drv_get_key_seq(sdata->local, key, &kseq);
+		params.seq = kseq.hw.seq;
+		params.seq_len = kseq.hw.seq_len;
+		break;
 	}
 
 	params.key = key->conf.key;
diff --git a/net/mac80211/key.c b/net/mac80211/key.c
index 3e0b814..0a5d5c5 100644
--- a/net/mac80211/key.c
+++ b/net/mac80211/key.c
@@ -485,8 +485,8 @@
 		break;
 	default:
 		if (cs) {
-			size_t len = (seq_len > MAX_PN_LEN) ?
-						MAX_PN_LEN : seq_len;
+			size_t len = (seq_len > IEEE80211_MAX_PN_LEN) ?
+						IEEE80211_MAX_PN_LEN : seq_len;
 
 			key->conf.iv_len = cs->hdr_len;
 			key->conf.icv_len = cs->mic_len;
diff --git a/net/mac80211/key.h b/net/mac80211/key.h
index c5a3183..df430a6 100644
--- a/net/mac80211/key.h
+++ b/net/mac80211/key.h
@@ -18,7 +18,6 @@
 
 #define NUM_DEFAULT_KEYS 4
 #define NUM_DEFAULT_MGMT_KEYS 2
-#define MAX_PN_LEN 16
 
 struct ieee80211_local;
 struct ieee80211_sub_if_data;
@@ -116,7 +115,7 @@
 		} gcmp;
 		struct {
 			/* generic cipher scheme */
-			u8 rx_pn[IEEE80211_NUM_TIDS + 1][MAX_PN_LEN];
+			u8 rx_pn[IEEE80211_NUM_TIDS + 1][IEEE80211_MAX_PN_LEN];
 		} gen;
 	} u;