cfg80211/nl80211: separate unicast/multicast default TX keys

Allow userspace to specify that a given key
is default only for unicast and/or multicast
transmissions. Only WEP keys are for both,
WPA/RSN keys set here are GTKs for multicast
only. For more future flexibility, allow to
specify all combiations.

Wireless extensions can only set both so use
nl80211; WEP keys (connect keys) must be set
as default for both (but 802.1X WEP is still
possible).

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 107 insertions, 18 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 73a7f6d354c9..53f044370cde 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -171,6 +171,7 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = {
         [NL80211_ATTR_WIPHY_ANTENNA_RX] = { .type = NLA_U32 },
         [NL80211_ATTR_MCAST_RATE] = { .type = NLA_U32 },
         [NL80211_ATTR_OFFCHANNEL_TX_OK] = { .type = NLA_FLAG },
+        [NL80211_ATTR_KEY_DEFAULT_TYPES] = { .type = NLA_NESTED },
 };
 
 /* policy for the key attributes */
@@ -182,6 +183,14 @@ static const struct nla_policy nl80211_key_policy[NL80211_KEY_MAX + 1] = {
         [NL80211_KEY_DEFAULT] = { .type = NLA_FLAG },
         [NL80211_KEY_DEFAULT_MGMT] = { .type = NLA_FLAG },
         [NL80211_KEY_TYPE] = { .type = NLA_U32 },
+        [NL80211_KEY_DEFAULT_TYPES] = { .type = NLA_NESTED },
+};
+
+/* policy for the key default flags */
+static const struct nla_policy
+nl80211_key_default_policy[NUM_NL80211_KEY_DEFAULT_TYPES] = {
+        [NL80211_KEY_DEFAULT_TYPE_UNICAST] = { .type = NLA_FLAG },
+        [NL80211_KEY_DEFAULT_TYPE_MULTICAST] = { .type = NLA_FLAG },
 };
 
 /* ifidx get helper */
@@ -314,6 +323,7 @@ struct key_parse {
         int idx;
         int type;
         bool def, defmgmt;
+        bool def_uni, def_multi;
 };
 
 static int nl80211_parse_key_new(struct nlattr *key, struct key_parse *k)
@@ -327,6 +337,13 @@ static int nl80211_parse_key_new(struct nlattr *key, struct key_parse *k)
         k->def = !!tb[NL80211_KEY_DEFAULT];
         k->defmgmt = !!tb[NL80211_KEY_DEFAULT_MGMT];
 
+        if (k->def) {
+                k->def_uni = true;
+                k->def_multi = true;
+        }
+        if (k->defmgmt)
+                k->def_multi = true;
+
         if (tb[NL80211_KEY_IDX])
                 k->idx = nla_get_u8(tb[NL80211_KEY_IDX]);
 
@@ -349,6 +366,19 @@ static int nl80211_parse_key_new(struct nlattr *key, struct key_parse *k)
                         return -EINVAL;
         }
 
+        if (tb[NL80211_KEY_DEFAULT_TYPES]) {
+                struct nlattr *kdt[NUM_NL80211_KEY_DEFAULT_TYPES];
+                int err = nla_parse_nested(kdt,
+                                           NUM_NL80211_KEY_DEFAULT_TYPES - 1,
+                                           tb[NL80211_KEY_DEFAULT_TYPES],
+                                           nl80211_key_default_policy);
+                if (err)
+                        return err;
+
+                k->def_uni = kdt[NL80211_KEY_DEFAULT_TYPE_UNICAST];
+                k->def_multi = kdt[NL80211_KEY_DEFAULT_TYPE_MULTICAST];
+        }
+
         return 0;
 }
 
@@ -373,12 +403,32 @@ static int nl80211_parse_key_old(struct genl_info *info, struct key_parse *k)
         k->def = !!info->attrs[NL80211_ATTR_KEY_DEFAULT];
         k->defmgmt = !!info->attrs[NL80211_ATTR_KEY_DEFAULT_MGMT];
 
+        if (k->def) {
+                k->def_uni = true;
+                k->def_multi = true;
+        }
+        if (k->defmgmt)
+                k->def_multi = true;
+
         if (info->attrs[NL80211_ATTR_KEY_TYPE]) {
                 k->type = nla_get_u32(info->attrs[NL80211_ATTR_KEY_TYPE]);
                 if (k->type < 0 || k->type >= NUM_NL80211_KEYTYPES)
                         return -EINVAL;
         }
 
+        if (info->attrs[NL80211_ATTR_KEY_DEFAULT_TYPES]) {
+                struct nlattr *kdt[NUM_NL80211_KEY_DEFAULT_TYPES];
+                int err = nla_parse_nested(
+                                kdt, NUM_NL80211_KEY_DEFAULT_TYPES - 1,
+                                info->attrs[NL80211_ATTR_KEY_DEFAULT_TYPES],
+                                nl80211_key_default_policy);
+                if (err)
+                        return err;
+
+                k->def_uni = kdt[NL80211_KEY_DEFAULT_TYPE_UNICAST];
+                k->def_multi = kdt[NL80211_KEY_DEFAULT_TYPE_MULTICAST];
+        }
+
         return 0;
 }
 
@@ -401,6 +451,11 @@ static int nl80211_parse_key(struct genl_info *info, struct key_parse *k)
         if (k->def && k->defmgmt)
                 return -EINVAL;
 
+        if (k->defmgmt) {
+                if (k->def_uni || !k->def_multi)
+                        return -EINVAL;
+        }
+
         if (k->idx != -1) {
                 if (k->defmgmt) {
                         if (k->idx < 4 || k->idx > 5)
@@ -450,6 +505,8 @@ nl80211_parse_connkeys(struct cfg80211_registered_device *rdev,
                                 goto error;
                         def = 1;
                         result->def = parse.idx;
+                        if (!parse.def_uni || !parse.def_multi)
+                                goto error;
                 } else if (parse.defmgmt)
                         goto error;
                 err = cfg80211_validate_key_settings(rdev, &parse.p,
@@ -1586,8 +1643,6 @@ static int nl80211_set_key(struct sk_buff *skb, struct genl_info *info)
         struct key_parse key;
         int err;
         struct net_device *dev = info->user_ptr[1];
-        int (*func)(struct wiphy *wiphy, struct net_device *netdev,
-                    u8 key_index);
 
         err = nl80211_parse_key(info, &key);
         if (err)
@@ -1600,27 +1655,61 @@ static int nl80211_set_key(struct sk_buff *skb, struct genl_info *info)
         if (!key.def && !key.defmgmt)
                 return -EINVAL;
 
-        if (key.def)
-                func = rdev->ops->set_default_key;
-        else
-                func = rdev->ops->set_default_mgmt_key;
+        wdev_lock(dev->ieee80211_ptr);
 
-        if (!func)
-                return -EOPNOTSUPP;
+        if (key.def) {
+                if (!rdev->ops->set_default_key) {
+                        err = -EOPNOTSUPP;
+                        goto out;
+                }
 
-        wdev_lock(dev->ieee80211_ptr);
-        err = nl80211_key_allowed(dev->ieee80211_ptr);
-        if (!err)
-                err = func(&rdev->wiphy, dev, key.idx);
+                err = nl80211_key_allowed(dev->ieee80211_ptr);
+                if (err)
+                        goto out;
+
+                if (!(rdev->wiphy.flags &
+                                WIPHY_FLAG_SUPPORTS_SEPARATE_DEFAULT_KEYS)) {
+                        if (!key.def_uni || !key.def_multi) {
+                                err = -EOPNOTSUPP;
+                                goto out;
+                        }
+                }
+
+                err = rdev->ops->set_default_key(&rdev->wiphy, dev, key.idx,
+                                                 key.def_uni, key.def_multi);
+
+                if (err)
+                        goto out;
 
 #ifdef CONFIG_CFG80211_WEXT
-        if (!err) {
-                if (func == rdev->ops->set_default_key)
-                        dev->ieee80211_ptr->wext.default_key = key.idx;
-                else
-                        dev->ieee80211_ptr->wext.default_mgmt_key = key.idx;
-        }
+                dev->ieee80211_ptr->wext.default_key = key.idx;
+#endif
+        } else {
+                if (key.def_uni || !key.def_multi) {
+                        err = -EINVAL;
+                        goto out;
+                }
+
+                if (!rdev->ops->set_default_mgmt_key) {
+                        err = -EOPNOTSUPP;
+                        goto out;
+                }
+
+                err = nl80211_key_allowed(dev->ieee80211_ptr);
+                if (err)
+                        goto out;
+
+                err = rdev->ops->set_default_mgmt_key(&rdev->wiphy,
+                                                      dev, key.idx);
+                if (err)
+                        goto out;
+
+#ifdef CONFIG_CFG80211_WEXT
+                dev->ieee80211_ptr->wext.default_mgmt_key = key.idx;
 #endif
+        }
+
+ out:
         wdev_unlock(dev->ieee80211_ptr);
 
         return err;