mac80211: add generic cipher scheme support
This adds generic cipher scheme support to mac80211, such schemes
are fully under control by the driver. On hw registration drivers
may specify additional HW ciphers with a scheme how these ciphers
have to be handled by mac80211 TX/RR. A cipher scheme specifies a
cipher suite value, a size of the security header to be added to
or stripped from frames and how the PN is to be verified on RX.
Signed-off-by: Max Stepanov <Max.Stepanov@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index fd4fe5d..5dfa41a 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -2475,3 +2475,71 @@
ieee80211_tx_skb(sdata, skb);
return 0;
}
+
+bool ieee80211_cs_valid(const struct ieee80211_cipher_scheme *cs)
+{
+ return !(cs == NULL || cs->cipher == 0 ||
+ cs->hdr_len < cs->pn_len + cs->pn_off ||
+ cs->hdr_len <= cs->key_idx_off ||
+ cs->key_idx_shift > 7 ||
+ cs->key_idx_mask == 0);
+}
+
+bool ieee80211_cs_list_valid(const struct ieee80211_cipher_scheme *cs, int n)
+{
+ int i;
+
+ /* Ensure we have enough iftype bitmap space for all iftype values */
+ WARN_ON((NUM_NL80211_IFTYPES / 8 + 1) > sizeof(cs[0].iftype));
+
+ for (i = 0; i < n; i++)
+ if (!ieee80211_cs_valid(&cs[i]))
+ return false;
+
+ return true;
+}
+
+const struct ieee80211_cipher_scheme *
+ieee80211_cs_get(struct ieee80211_local *local, u32 cipher,
+ enum nl80211_iftype iftype)
+{
+ const struct ieee80211_cipher_scheme *l = local->hw.cipher_schemes;
+ int n = local->hw.n_cipher_schemes;
+ int i;
+ const struct ieee80211_cipher_scheme *cs = NULL;
+
+ for (i = 0; i < n; i++) {
+ if (l[i].cipher == cipher) {
+ cs = &l[i];
+ break;
+ }
+ }
+
+ if (!cs || !(cs->iftype & BIT(iftype)))
+ return NULL;
+
+ return cs;
+}
+
+int ieee80211_cs_headroom(struct ieee80211_local *local,
+ struct cfg80211_crypto_settings *crypto,
+ enum nl80211_iftype iftype)
+{
+ const struct ieee80211_cipher_scheme *cs;
+ int headroom = IEEE80211_ENCRYPT_HEADROOM;
+ int i;
+
+ for (i = 0; i < crypto->n_ciphers_pairwise; i++) {
+ cs = ieee80211_cs_get(local, crypto->ciphers_pairwise[i],
+ iftype);
+
+ if (cs && headroom < cs->hdr_len)
+ headroom = cs->hdr_len;
+ }
+
+ cs = ieee80211_cs_get(local, crypto->cipher_group, iftype);
+ if (cs && headroom < cs->hdr_len)
+ headroom = cs->hdr_len;
+
+ return headroom;
+}