nl80211: introduce new key attributes

We will soon want to nest key attributes into
some new attribute for configuring static WEP
keys at connect() and ibss_join() time, so we
need nested attributes for that. However, key
attributes right now are 'global'. This patch
thus introduces new nested attributes for the
key settings and functions for parsing them.

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

diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index e496a2d..48e0913 100644 (file)
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -567,6 +567,9 @@ enum nl80211_commands {
  * @NL80211_ATTR_PREV_BSSID: previous BSSID, to be used by in ASSOCIATE
  *     commands to specify using a reassociate frame
  *
+ * @NL80211_ATTR_KEY: key information in a nested attribute with
+ *     %NL80211_KEY_* sub-attributes
+ *
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
  */
@@ -692,6 +695,8 @@ enum nl80211_attrs {
 
        NL80211_ATTR_PREV_BSSID,
 
+       NL80211_ATTR_KEY,
+
        /* add attributes here, update the policy in nl80211.c */
 
        __NL80211_ATTR_AFTER_LAST,
@@ -720,6 +725,7 @@ enum nl80211_attrs {
 #define NL80211_ATTR_CIPHER_SUITE_GROUP NL80211_ATTR_CIPHER_SUITE_GROUP
 #define NL80211_ATTR_WPA_VERSIONS NL80211_ATTR_WPA_VERSIONS
 #define NL80211_ATTR_AKM_SUITES NL80211_ATTR_AKM_SUITES
+#define NL80211_ATTR_KEY NL80211_ATTR_KEY
 
 #define NL80211_MAX_SUPP_RATES                 32
 #define NL80211_MAX_SUPP_REG_RULES             32
@@ -1320,4 +1326,34 @@ enum nl80211_wpa_versions {
        NL80211_WPA_VERSION_2 = 1 << 1,
 };
 
+/**
+ * enum nl80211_key_attributes - key attributes
+ * @__NL80211_KEY_INVALID: invalid
+ * @NL80211_KEY_DATA: (temporal) key data; for TKIP this consists of
+ *     16 bytes encryption key followed by 8 bytes each for TX and RX MIC
+ *     keys
+ * @NL80211_KEY_IDX: key ID (u8, 0-3)
+ * @NL80211_KEY_CIPHER: key cipher suite (u32, as defined by IEEE 802.11
+ *     section 7.3.2.25.1, e.g. 0x000FAC04)
+ * @NL80211_KEY_SEQ: transmit key sequence number (IV/PN) for TKIP and
+ *     CCMP keys, each six bytes in little endian
+ * @NL80211_KEY_DEFAULT: flag indicating default key
+ * @NL80211_KEY_DEFAULT_MGMT: flag indicating default management key
+ * @__NL80211_KEY_AFTER_LAST: internal
+ * @NL80211_KEY_MAX: highest key attribute
+ */
+enum nl80211_key_attributes {
+       __NL80211_KEY_INVALID,
+       NL80211_KEY_DATA,
+       NL80211_KEY_IDX,
+       NL80211_KEY_CIPHER,
+       NL80211_KEY_SEQ,
+       NL80211_KEY_DEFAULT,
+       NL80211_KEY_DEFAULT_MGMT,
+
+       /* keep last */
+       __NL80211_KEY_AFTER_LAST,
+       NL80211_KEY_MAX = __NL80211_KEY_AFTER_LAST - 1
+};
+
 #endif /* __LINUX_NL80211_H */

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index a00fd64..50cf593 100644 (file)
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -73,6 +73,7 @@ static struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] __read_mostly = {
        [NL80211_ATTR_MAC] = { .type = NLA_BINARY, .len = ETH_ALEN },
        [NL80211_ATTR_PREV_BSSID] = { .type = NLA_BINARY, .len = ETH_ALEN },
 
+       [NL80211_ATTR_KEY] = { .type = NLA_NESTED, },
        [NL80211_ATTR_KEY_DATA] = { .type = NLA_BINARY,
                                    .len = WLAN_MAX_KEY_LEN },
        [NL80211_ATTR_KEY_IDX] = { .type = NLA_U8 },
@@ -134,6 +135,18 @@ static struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] __read_mostly = {
        [NL80211_ATTR_WPA_VERSIONS] = { .type = NLA_U32 },
 };
 
+/* policy for the attributes */
+static struct nla_policy
+nl80211_key_policy[NL80211_KEY_MAX + 1] __read_mostly = {
+       [NL80211_KEY_DATA] = { .type = NLA_BINARY,
+                                   .len = WLAN_MAX_KEY_LEN },
+       [NL80211_KEY_IDX] = { .type = NLA_U8 },
+       [NL80211_KEY_CIPHER] = { .type = NLA_U32 },
+       [NL80211_KEY_SEQ] = { .type = NLA_BINARY, .len = 8 },
+       [NL80211_KEY_DEFAULT] = { .type = NLA_FLAG },
+       [NL80211_KEY_DEFAULT_MGMT] = { .type = NLA_FLAG },
+};
+
 /* IE validation */
 static bool is_valid_ie_attr(const struct nlattr *attr)
 {
@@ -198,6 +211,100 @@ static int nl80211_msg_put_channel(struct sk_buff *msg,
 
 /* netlink command implementations */
 
+struct key_parse {
+       struct key_params p;
+       int idx;
+       bool def, defmgmt;
+};
+
+static int nl80211_parse_key_new(struct nlattr *key, struct key_parse *k)
+{
+       struct nlattr *tb[NL80211_KEY_MAX + 1];
+       int err = nla_parse_nested(tb, NL80211_KEY_MAX, key,
+                                  nl80211_key_policy);
+       if (err)
+               return err;
+
+       k->def = !!tb[NL80211_KEY_DEFAULT];
+       k->defmgmt = !!tb[NL80211_KEY_DEFAULT_MGMT];
+
+       if (tb[NL80211_KEY_IDX])
+               k->idx = nla_get_u8(tb[NL80211_KEY_IDX]);
+
+       if (tb[NL80211_KEY_DATA]) {
+               k->p.key = nla_data(tb[NL80211_KEY_DATA]);
+               k->p.key_len = nla_len(tb[NL80211_KEY_DATA]);
+       }
+
+       if (tb[NL80211_KEY_SEQ]) {
+               k->p.seq = nla_data(tb[NL80211_KEY_SEQ]);
+               k->p.seq_len = nla_len(tb[NL80211_KEY_SEQ]);
+       }
+
+       if (tb[NL80211_KEY_CIPHER])
+               k->p.cipher = nla_get_u32(tb[NL80211_KEY_CIPHER]);
+
+       return 0;
+}
+
+static int nl80211_parse_key_old(struct genl_info *info, struct key_parse *k)
+{
+       if (info->attrs[NL80211_ATTR_KEY_DATA]) {
+               k->p.key = nla_data(info->attrs[NL80211_ATTR_KEY_DATA]);
+               k->p.key_len = nla_len(info->attrs[NL80211_ATTR_KEY_DATA]);
+       }
+
+       if (info->attrs[NL80211_ATTR_KEY_SEQ]) {
+               k->p.seq = nla_data(info->attrs[NL80211_ATTR_KEY_SEQ]);
+               k->p.seq_len = nla_len(info->attrs[NL80211_ATTR_KEY_SEQ]);
+       }
+
+       if (info->attrs[NL80211_ATTR_KEY_IDX])
+               k->idx = nla_get_u8(info->attrs[NL80211_ATTR_KEY_IDX]);
+
+       if (info->attrs[NL80211_ATTR_KEY_CIPHER])
+               k->p.cipher = nla_get_u32(info->attrs[NL80211_ATTR_KEY_CIPHER]);
+
+       k->def = !!info->attrs[NL80211_ATTR_KEY_DEFAULT];
+       k->defmgmt = !!info->attrs[NL80211_ATTR_KEY_DEFAULT_MGMT];
+
+       return 0;
+}
+
+static int nl80211_parse_key(struct genl_info *info, struct key_parse *k)
+{
+       int err;
+
+       memset(k, 0, sizeof(*k));
+       k->idx = -1;
+
+       if (info->attrs[NL80211_ATTR_KEY])
+               err = nl80211_parse_key_new(info->attrs[NL80211_ATTR_KEY], k);
+       else
+               err = nl80211_parse_key_old(info, k);
+
+       if (err)
+               return err;
+
+       if (k->def && k->defmgmt)
+               return -EINVAL;
+
+       if (k->idx != -1) {
+               if (k->defmgmt) {
+                       if (k->idx < 4 || k->idx > 5)
+                               return -EINVAL;
+               } else if (k->def) {
+                       if (k->idx < 0 || k->idx > 3)
+                               return -EINVAL;
+               } else {
+                       if (k->idx < 0 || k->idx > 5)
+                               return -EINVAL;
+               }
+       }
+
+       return 0;
+}
+
 static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags,
                              struct cfg80211_registered_device *dev)
 {
@@ -943,10 +1050,12 @@ static int nl80211_del_interface(struct sk_buff *skb, struct genl_info *info)
 struct get_key_cookie {
        struct sk_buff *msg;
        int error;
+       int idx;
 };
 
 static void get_key_callback(void *c, struct key_params *params)
 {
+       struct nlattr *key;
        struct get_key_cookie *cookie = c;
 
        if (params->key)
@@ -961,6 +1070,26 @@ static void get_key_callback(void *c, struct key_params *params)
                NLA_PUT_U32(cookie->msg, NL80211_ATTR_KEY_CIPHER,
                            params->cipher);
 
+       key = nla_nest_start(cookie->msg, NL80211_ATTR_KEY);
+       if (!key)
+               goto nla_put_failure;
+
+       if (params->key)
+               NLA_PUT(cookie->msg, NL80211_KEY_DATA,
+                       params->key_len, params->key);
+
+       if (params->seq)
+               NLA_PUT(cookie->msg, NL80211_KEY_SEQ,
+                       params->seq_len, params->seq);
+
+       if (params->cipher)
+               NLA_PUT_U32(cookie->msg, NL80211_KEY_CIPHER,
+                           params->cipher);
+
+       NLA_PUT_U8(cookie->msg, NL80211_ATTR_KEY_IDX, cookie->idx);
+
+       nla_nest_end(cookie->msg, key);
+
        return;
  nla_put_failure:
        cookie->error = 1;
@@ -1014,6 +1143,7 @@ static int nl80211_get_key(struct sk_buff *skb, struct genl_info *info)
        }
 
        cookie.msg = msg;
+       cookie.idx = key_idx;
 
        NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, dev->ifindex);
        NLA_PUT_U8(msg, NL80211_ATTR_KEY_IDX, key_idx);
@@ -1049,26 +1179,21 @@ static int nl80211_get_key(struct sk_buff *skb, struct genl_info *info)
 static int nl80211_set_key(struct sk_buff *skb, struct genl_info *info)
 {
        struct cfg80211_registered_device *rdev;
+       struct key_parse key;
        int err;
        struct net_device *dev;
-       u8 key_idx;
        int (*func)(struct wiphy *wiphy, struct net_device *netdev,
                    u8 key_index);
 
-       if (!info->attrs[NL80211_ATTR_KEY_IDX])
-               return -EINVAL;
-
-       key_idx = nla_get_u8(info->attrs[NL80211_ATTR_KEY_IDX]);
+       err = nl80211_parse_key(info, &key);
+       if (err)
+               return err;
 
-       if (info->attrs[NL80211_ATTR_KEY_DEFAULT_MGMT]) {
-               if (key_idx < 4 || key_idx > 5)
-                       return -EINVAL;
-       } else if (key_idx > 3)
+       if (key.idx < 0)
                return -EINVAL;
 
-       /* currently only support setting default key */
-       if (!info->attrs[NL80211_ATTR_KEY_DEFAULT] &&
-           !info->attrs[NL80211_ATTR_KEY_DEFAULT_MGMT])
+       /* only support setting default key */
+       if (!key.def && !key.defmgmt)
                return -EINVAL;
 
        rtnl_lock();
@@ -1077,7 +1202,7 @@ static int nl80211_set_key(struct sk_buff *skb, struct genl_info *info)
        if (err)
                goto unlock_rtnl;
 
-       if (info->attrs[NL80211_ATTR_KEY_DEFAULT])
+       if (key.def)
                func = rdev->ops->set_default_key;
        else
                func = rdev->ops->set_default_mgmt_key;
@@ -1087,13 +1212,13 @@ static int nl80211_set_key(struct sk_buff *skb, struct genl_info *info)
                goto out;
        }
 
-       err = func(&rdev->wiphy, dev, key_idx);
+       err = func(&rdev->wiphy, dev, key.idx);
 #ifdef CONFIG_WIRELESS_EXT
        if (!err) {
                if (func == rdev->ops->set_default_key)
-                       dev->ieee80211_ptr->wext.default_key = key_idx;
+                       dev->ieee80211_ptr->wext.default_key = key.idx;
                else
-                       dev->ieee80211_ptr->wext.default_mgmt_key = key_idx;
+                       dev->ieee80211_ptr->wext.default_mgmt_key = key.idx;
        }
 #endif
 
@@ -1112,34 +1237,20 @@ static int nl80211_new_key(struct sk_buff *skb, struct genl_info *info)
        struct cfg80211_registered_device *rdev;
        int err, i;
        struct net_device *dev;
-       struct key_params params;
-       u8 key_idx = 0;
+       struct key_parse key;
        u8 *mac_addr = NULL;
 
-       memset(&params, 0, sizeof(params));
+       err = nl80211_parse_key(info, &key);
+       if (err)
+               return err;
 
-       if (!info->attrs[NL80211_ATTR_KEY_CIPHER])
+       if (!key.p.key)
                return -EINVAL;
 
-       if (info->attrs[NL80211_ATTR_KEY_DATA]) {
-               params.key = nla_data(info->attrs[NL80211_ATTR_KEY_DATA]);
-               params.key_len = nla_len(info->attrs[NL80211_ATTR_KEY_DATA]);
-       }
-
-       if (info->attrs[NL80211_ATTR_KEY_SEQ]) {
-               params.seq = nla_data(info->attrs[NL80211_ATTR_KEY_SEQ]);
-               params.seq_len = nla_len(info->attrs[NL80211_ATTR_KEY_SEQ]);
-       }
-
-       if (info->attrs[NL80211_ATTR_KEY_IDX])
-               key_idx = nla_get_u8(info->attrs[NL80211_ATTR_KEY_IDX]);
-
-       params.cipher = nla_get_u32(info->attrs[NL80211_ATTR_KEY_CIPHER]);
-
        if (info->attrs[NL80211_ATTR_MAC])
                mac_addr = nla_data(info->attrs[NL80211_ATTR_MAC]);
 
-       if (cfg80211_validate_key_settings(&params, key_idx, mac_addr))
+       if (cfg80211_validate_key_settings(&key.p, key.idx, mac_addr))
                return -EINVAL;
 
        rtnl_lock();
@@ -1149,7 +1260,7 @@ static int nl80211_new_key(struct sk_buff *skb, struct genl_info *info)
                goto unlock_rtnl;
 
        for (i = 0; i < rdev->wiphy.n_cipher_suites; i++)
-               if (params.cipher == rdev->wiphy.cipher_suites[i])
+               if (key.p.cipher == rdev->wiphy.cipher_suites[i])
                        break;
        if (i == rdev->wiphy.n_cipher_suites) {
                err = -EINVAL;
@@ -1161,7 +1272,7 @@ static int nl80211_new_key(struct sk_buff *skb, struct genl_info *info)
                goto out;
        }
 
-       err = rdev->ops->add_key(&rdev->wiphy, dev, key_idx, mac_addr, &params);
+       err = rdev->ops->add_key(&rdev->wiphy, dev, key.idx, mac_addr, &key.p);
 
  out:
        cfg80211_unlock_rdev(rdev);
@@ -1177,14 +1288,12 @@ static int nl80211_del_key(struct sk_buff *skb, struct genl_info *info)
        struct cfg80211_registered_device *rdev;
        int err;
        struct net_device *dev;
-       u8 key_idx = 0;
        u8 *mac_addr = NULL;
+       struct key_parse key;
 
-       if (info->attrs[NL80211_ATTR_KEY_IDX])
-               key_idx = nla_get_u8(info->attrs[NL80211_ATTR_KEY_IDX]);
-
-       if (key_idx > 5)
-               return -EINVAL;
+       err = nl80211_parse_key(info, &key);
+       if (err)
+               return err;
 
        if (info->attrs[NL80211_ATTR_MAC])
                mac_addr = nla_data(info->attrs[NL80211_ATTR_MAC]);
@@ -1200,13 +1309,13 @@ static int nl80211_del_key(struct sk_buff *skb, struct genl_info *info)
                goto out;
        }
 
-       err = rdev->ops->del_key(&rdev->wiphy, dev, key_idx, mac_addr);
+       err = rdev->ops->del_key(&rdev->wiphy, dev, key.idx, mac_addr);
 
 #ifdef CONFIG_WIRELESS_EXT
        if (!err) {
-               if (key_idx == dev->ieee80211_ptr->wext.default_key)
+               if (key.idx == dev->ieee80211_ptr->wext.default_key)
                        dev->ieee80211_ptr->wext.default_key = -1;
-               else if (key_idx == dev->ieee80211_ptr->wext.default_mgmt_key)
+               else if (key.idx == dev->ieee80211_ptr->wext.default_mgmt_key)
                        dev->ieee80211_ptr->wext.default_mgmt_key = -1;
        }
 #endif