cfg80211/nl80211: Add userspace authentication flag to mesh setup

During mesh setup, use NL80211_MESH_SETUP_USERSPACE_AUTH flag to create
a secure mesh and route management frames to userspace.

Also, NL80211_CMD_GET_WIPHY now returns a flag NL80211_SUPPORT_MESH_AUTH
if the wiphy's mesh implementation supports routing of mesh auth frames
to userspace.  This is useful for forward compatibility between old
kernels and new userspace tools.

Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

4 files changed, 23 insertions, 0 deletions

diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index ecf6b68a96da..0e652d860819 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -887,6 +887,9 @@ enum nl80211_commands {
  *      changed once the mesh is active.
  * @NL80211_ATTR_MESH_CONFIG: Mesh configuration parameters, a nested attribute
  *      containing attributes from &enum nl80211_meshconf_params.
+ * @NL80211_ATTR_SUPPORT_MESH_AUTH: Currently, this means the underlying driver
+ *      allows auth frames in a mesh to be passed to userspace for processing via
+ *      the @NL80211_MESH_SETUP_USERSPACE_AUTH flag.
  *
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -1075,6 +1078,8 @@ enum nl80211_attrs {
         NL80211_ATTR_WIPHY_ANTENNA_AVAIL_TX,
         NL80211_ATTR_WIPHY_ANTENNA_AVAIL_RX,
 
+        NL80211_ATTR_SUPPORT_MESH_AUTH,
+
         /* add attributes here, update the policy in nl80211.c */
 
         __NL80211_ATTR_AFTER_LAST,
@@ -1724,6 +1729,9 @@ enum nl80211_meshconf_params {
  * robust security network ie, or a vendor specific information element that
  * vendors will use to identify the path selection methods and metrics in use.
  *
+ * @NL80211_MESH_SETUP_USERSPACE_AUTH: Enable this option if an authentication
+ * daemon will be authenticating mesh candidates.
+ *
  * @NL80211_MESH_SETUP_ATTR_MAX: highest possible mesh setup attribute number
  * @__NL80211_MESH_SETUP_ATTR_AFTER_LAST: Internal use
  */
@@ -1732,6 +1740,7 @@ enum nl80211_mesh_setup_params {
         NL80211_MESH_SETUP_ENABLE_VENDOR_PATH_SEL,
         NL80211_MESH_SETUP_ENABLE_VENDOR_METRIC,
         NL80211_MESH_SETUP_IE,
+        NL80211_MESH_SETUP_USERSPACE_AUTH,
 
         /* keep last */
         __NL80211_MESH_SETUP_ATTR_AFTER_LAST,
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 1d02ddf5a8a3..e77603bd1630 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -691,6 +691,7 @@ struct mesh_config {
  * @path_metric: which metric to use
  * @ie: vendor information elements (optional)
  * @ie_len: length of vendor information elements
+ * @is_secure: or not
  *
  * These parameters are fixed when the mesh is created.
  */
@@ -701,6 +702,7 @@ struct mesh_setup {
         u8  path_metric;
         const u8 *ie;
         u8 ie_len;
+        bool is_secure;
 };
 
 /**
@@ -1451,6 +1453,8 @@ struct cfg80211_ops {
  * @WIPHY_FLAG_IBSS_RSN: The device supports IBSS RSN.
  * @WIPHY_FLAG_SUPPORTS_SEPARATE_DEFAULT_KEYS: The device supports separate
  *      unicast and multicast TX keys.
+ * @WIPHY_FLAG_MESH_AUTH: The device supports mesh authentication by routing
+ *      auth frames to userspace. See @NL80211_MESH_SETUP_USERSPACE_AUTH.
  */
 enum wiphy_flags {
         WIPHY_FLAG_CUSTOM_REGULATORY            = BIT(0),
@@ -1463,6 +1467,7 @@ enum wiphy_flags {
         WIPHY_FLAG_CONTROL_PORT_PROTOCOL        = BIT(7),
         WIPHY_FLAG_IBSS_RSN                     = BIT(8),
         WIPHY_FLAG_SUPPORTS_SEPARATE_DEFAULT_KEYS= BIT(9),
+        WIPHY_FLAG_MESH_AUTH                    = BIT(10),
 };
 
 struct mac_address {
diff --git a/net/wireless/mesh.c b/net/wireless/mesh.c
index 0d4b2260f96f..0e5c122ce324 100644
--- a/net/wireless/mesh.c
+++ b/net/wireless/mesh.c
@@ -72,6 +72,10 @@ int __cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
         if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_MESH_POINT)
                 return -EOPNOTSUPP;
 
+        if (!(rdev->wiphy.flags & WIPHY_FLAG_MESH_AUTH) &&
+              setup->is_secure)
+                return -EOPNOTSUPP;
+
         if (wdev->mesh_id_len)
                 return -EALREADY;
 
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index ccd825a5857e..cbedfc2a42a2 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -124,6 +124,7 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = {
         [NL80211_ATTR_BSS_HT_OPMODE] = { .type = NLA_U16 },
 
         [NL80211_ATTR_MESH_CONFIG] = { .type = NLA_NESTED },
+        [NL80211_ATTR_SUPPORT_MESH_AUTH] = { .type = NLA_FLAG },
 
         [NL80211_ATTR_HT_CAPABILITY] = { .type = NLA_BINARY,
                                          .len = NL80211_HT_CAPABILITY_LEN },
@@ -594,6 +595,8 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags,
 
         if (dev->wiphy.flags & WIPHY_FLAG_IBSS_RSN)
                 NLA_PUT_FLAG(msg, NL80211_ATTR_SUPPORT_IBSS_RSN);
+        if (dev->wiphy.flags & WIPHY_FLAG_MESH_AUTH)
+                NLA_PUT_FLAG(msg, NL80211_ATTR_SUPPORT_MESH_AUTH);
 
         NLA_PUT(msg, NL80211_ATTR_CIPHER_SUITES,
                 sizeof(u32) * dev->wiphy.n_cipher_suites,
@@ -2823,6 +2826,7 @@ static const struct nla_policy
         nl80211_mesh_setup_params_policy[NL80211_MESH_SETUP_ATTR_MAX+1] = {
         [NL80211_MESH_SETUP_ENABLE_VENDOR_PATH_SEL] = { .type = NLA_U8 },
         [NL80211_MESH_SETUP_ENABLE_VENDOR_METRIC] = { .type = NLA_U8 },
+        [NL80211_MESH_SETUP_USERSPACE_AUTH] = { .type = NLA_FLAG },
         [NL80211_MESH_SETUP_IE] = { .type = NLA_BINARY,
                 .len = IEEE80211_MAX_DATA_LEN },
 };
@@ -2934,6 +2938,7 @@ static int nl80211_parse_mesh_setup(struct genl_info *info,
                 setup->ie = nla_data(ieattr);
                 setup->ie_len = nla_len(ieattr);
         }
+        setup->is_secure = nla_get_flag(tb[NL80211_MESH_SETUP_USERSPACE_AUTH]);
 
         return 0;
 }