cfg80211/mac80211: add mesh join/leave commands

Instead of tying mesh activity to interface up,
add join and leave commands for mesh. Since we
must be backward compatible, let cfg80211 handle
joining a mesh if a mesh ID was pre-configured
when the device goes up.

Note that this therefore must modify mac80211 as
well since mac80211 needs to lose the logic to
start the mesh on interface up.

We now allow querying mesh parameters before the
mesh is connected, which simply returns defaults.
Setting them (internally renamed to "update") is
only allowed while connected. Specify them with
the new mesh join command instead where needed.

In mac80211, beaconing must now also follow the
mesh enabled/not enabled state, which is done
by testing the mesh ID.

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

6 files changed, 284 insertions, 24 deletions

diff --git a/net/wireless/Makefile b/net/wireless/Makefile
index e77e508126fa..55a28ab21db9 100644
--- a/net/wireless/Makefile
+++ b/net/wireless/Makefile
@@ -10,7 +10,7 @@ obj-$(CONFIG_WEXT_SPY) += wext-spy.o
 obj-$(CONFIG_WEXT_PRIV) += wext-priv.o
 
 cfg80211-y += core.o sysfs.o radiotap.o util.o reg.o scan.o nl80211.o
-cfg80211-y += mlme.o ibss.o sme.o chan.o ethtool.o
+cfg80211-y += mlme.o ibss.o sme.o chan.o ethtool.o mesh.o
 cfg80211-$(CONFIG_CFG80211_DEBUGFS) += debugfs.o
 cfg80211-$(CONFIG_CFG80211_WEXT) += wext-compat.o wext-sme.o
 cfg80211-$(CONFIG_CFG80211_INTERNAL_REGDB) += regdb.o
diff --git a/net/wireless/core.c b/net/wireless/core.c
index 630bcf0a2f04..79772fcc37bc 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -332,6 +332,7 @@ struct wiphy *wiphy_new(const struct cfg80211_ops *ops, int sizeof_priv)
         WARN_ON(ops->add_virtual_intf && !ops->del_virtual_intf);
         WARN_ON(ops->add_station && !ops->del_station);
         WARN_ON(ops->add_mpath && !ops->del_mpath);
+        WARN_ON(ops->join_mesh && !ops->leave_mesh);
 
         alloc_size = sizeof(*rdev) + sizeof_priv;
 
@@ -752,6 +753,9 @@ static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
                         cfg80211_mlme_down(rdev, dev);
                         wdev_unlock(wdev);
                         break;
+                case NL80211_IFTYPE_MESH_POINT:
+                        cfg80211_leave_mesh(rdev, dev);
+                        break;
                 default:
                         break;
                 }
@@ -775,20 +779,27 @@ static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
                 }
                 cfg80211_lock_rdev(rdev);
                 mutex_lock(&rdev->devlist_mtx);
-#ifdef CONFIG_CFG80211_WEXT
                 wdev_lock(wdev);
                 switch (wdev->iftype) {
+#ifdef CONFIG_CFG80211_WEXT
                 case NL80211_IFTYPE_ADHOC:
                         cfg80211_ibss_wext_join(rdev, wdev);
                         break;
                 case NL80211_IFTYPE_STATION:
                         cfg80211_mgd_wext_connect(rdev, wdev);
                         break;
+#endif
+                case NL80211_IFTYPE_MESH_POINT:
+                        /* backward compat code ... */
+                        if (wdev->mesh_id_up_len)
+                                __cfg80211_join_mesh(rdev, dev, wdev->ssid,
+                                                     wdev->mesh_id_up_len,
+                                                     &default_mesh_config);
+                        break;
                 default:
                         break;
                 }
                 wdev_unlock(wdev);
-#endif
                 rdev->opencount++;
                 mutex_unlock(&rdev->devlist_mtx);
                 cfg80211_unlock_rdev(rdev);
diff --git a/net/wireless/core.h b/net/wireless/core.h
index ee80ad8dc655..743203bb61ac 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -285,6 +285,19 @@ void __cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid);
 int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
                             struct wireless_dev *wdev);
 
+/* mesh */
+extern const struct mesh_config default_mesh_config;
+int __cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
+                         struct net_device *dev,
+                         const u8 *mesh_id, u8 mesh_id_len,
+                         const struct mesh_config *conf);
+int cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
+                       struct net_device *dev,
+                       const u8 *mesh_id, u8 mesh_id_len,
+                       const struct mesh_config *conf);
+int cfg80211_leave_mesh(struct cfg80211_registered_device *rdev,
+                        struct net_device *dev);
+
 /* MLME */
 int __cfg80211_mlme_auth(struct cfg80211_registered_device *rdev,
                          struct net_device *dev,
diff --git a/net/wireless/mesh.c b/net/wireless/mesh.c
new file mode 100644
index 000000000000..e0b9747fe50a
--- /dev/null
+++ b/net/wireless/mesh.c
@@ -0,0 +1,140 @@
+#include <linux/ieee80211.h>
+#include <net/cfg80211.h>
+#include "core.h"
+
+/* Default values, timeouts in ms */
+#define MESH_TTL                31
+#define MESH_DEFAULT_ELEMENT_TTL 31
+#define MESH_MAX_RETR           3
+#define MESH_RET_T              100
+#define MESH_CONF_T             100
+#define MESH_HOLD_T             100
+
+#define MESH_PATH_TIMEOUT       5000
+
+/*
+ * Minimum interval between two consecutive PREQs originated by the same
+ * interface
+ */
+#define MESH_PREQ_MIN_INT       10
+#define MESH_DIAM_TRAVERSAL_TIME 50
+
+/*
+ * A path will be refreshed if it is used PATH_REFRESH_TIME milliseconds
+ * before timing out.  This way it will remain ACTIVE and no data frames
+ * will be unnecessarily held in the pending queue.
+ */
+#define MESH_PATH_REFRESH_TIME                  1000
+#define MESH_MIN_DISCOVERY_TIMEOUT (2 * MESH_DIAM_TRAVERSAL_TIME)
+
+/* Default maximum number of established plinks per interface */
+#define MESH_MAX_ESTAB_PLINKS   32
+
+#define MESH_MAX_PREQ_RETRIES   4
+
+
+const struct mesh_config default_mesh_config = {
+        .dot11MeshRetryTimeout = MESH_RET_T,
+        .dot11MeshConfirmTimeout = MESH_CONF_T,
+        .dot11MeshHoldingTimeout = MESH_HOLD_T,
+        .dot11MeshMaxRetries = MESH_MAX_RETR,
+        .dot11MeshTTL = MESH_TTL,
+        .element_ttl = MESH_DEFAULT_ELEMENT_TTL,
+        .auto_open_plinks = true,
+        .dot11MeshMaxPeerLinks = MESH_MAX_ESTAB_PLINKS,
+        .dot11MeshHWMPactivePathTimeout = MESH_PATH_TIMEOUT,
+        .dot11MeshHWMPpreqMinInterval = MESH_PREQ_MIN_INT,
+        .dot11MeshHWMPnetDiameterTraversalTime = MESH_DIAM_TRAVERSAL_TIME,
+        .dot11MeshHWMPmaxPREQretries = MESH_MAX_PREQ_RETRIES,
+        .path_refresh_time = MESH_PATH_REFRESH_TIME,
+        .min_discovery_timeout = MESH_MIN_DISCOVERY_TIMEOUT,
+};
+
+
+int __cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
+                         struct net_device *dev,
+                         const u8 *mesh_id, u8 mesh_id_len,
+                         const struct mesh_config *conf)
+{
+        struct wireless_dev *wdev = dev->ieee80211_ptr;
+        struct mesh_setup setup = {
+                .mesh_id = mesh_id,
+                .mesh_id_len = mesh_id_len,
+        };
+        int err;
+
+        BUILD_BUG_ON(IEEE80211_MAX_SSID_LEN != IEEE80211_MAX_MESH_ID_LEN);
+
+        ASSERT_WDEV_LOCK(wdev);
+
+        if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_MESH_POINT)
+                return -EOPNOTSUPP;
+
+        if (wdev->mesh_id_len)
+                return -EALREADY;
+
+        if (!mesh_id_len)
+                return -EINVAL;
+
+        if (!rdev->ops->join_mesh)
+                return -EOPNOTSUPP;
+
+        err = rdev->ops->join_mesh(&rdev->wiphy, dev, conf, &setup);
+        if (!err) {
+                memcpy(wdev->ssid, mesh_id, mesh_id_len);
+                wdev->mesh_id_len = mesh_id_len;
+        }
+
+        return err;
+}
+
+int cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
+                       struct net_device *dev,
+                       const u8 *mesh_id, u8 mesh_id_len,
+                       const struct mesh_config *conf)
+{
+        struct wireless_dev *wdev = dev->ieee80211_ptr;
+        int err;
+
+        wdev_lock(wdev);
+        err = __cfg80211_join_mesh(rdev, dev, mesh_id, mesh_id_len, conf);
+        wdev_unlock(wdev);
+
+        return err;
+}
+
+static int __cfg80211_leave_mesh(struct cfg80211_registered_device *rdev,
+                                 struct net_device *dev)
+{
+        struct wireless_dev *wdev = dev->ieee80211_ptr;
+        int err;
+
+        ASSERT_WDEV_LOCK(wdev);
+
+        if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_MESH_POINT)
+                return -EOPNOTSUPP;
+
+        if (!rdev->ops->leave_mesh)
+                return -EOPNOTSUPP;
+
+        if (!wdev->mesh_id_len)
+                return -ENOTCONN;
+
+        err = rdev->ops->leave_mesh(&rdev->wiphy, dev);
+        if (!err)
+                wdev->mesh_id_len = 0;
+        return err;
+}
+
+int cfg80211_leave_mesh(struct cfg80211_registered_device *rdev,
+                        struct net_device *dev)
+{
+        struct wireless_dev *wdev = dev->ieee80211_ptr;
+        int err;
+
+        wdev_lock(wdev);
+        err = __cfg80211_leave_mesh(rdev, dev);
+        wdev_unlock(wdev);
+
+        return err;
+}
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index c8d4d53fc450..56508d40c740 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -661,13 +661,14 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags,
         CMD(add_beacon, NEW_BEACON);
         CMD(add_station, NEW_STATION);
         CMD(add_mpath, NEW_MPATH);
-        CMD(set_mesh_params, SET_MESH_PARAMS);
+        CMD(update_mesh_params, SET_MESH_PARAMS);
         CMD(change_bss, SET_BSS);
         CMD(auth, AUTHENTICATE);
         CMD(assoc, ASSOCIATE);
         CMD(deauth, DEAUTHENTICATE);
         CMD(disassoc, DISASSOCIATE);
         CMD(join_ibss, JOIN_IBSS);
+        CMD(join_mesh, JOIN_MESH);
         CMD(set_pmksa, SET_PMKSA);
         CMD(del_pmksa, DEL_PMKSA);
         CMD(flush_pmksa, FLUSH_PMKSA);
@@ -1324,11 +1325,21 @@ static int nl80211_set_interface(struct sk_buff *skb, struct genl_info *info)
         }
 
         if (info->attrs[NL80211_ATTR_MESH_ID]) {
+                struct wireless_dev *wdev = dev->ieee80211_ptr;
+
                 if (ntype != NL80211_IFTYPE_MESH_POINT)
                         return -EINVAL;
-                params.mesh_id = nla_data(info->attrs[NL80211_ATTR_MESH_ID]);
-                params.mesh_id_len = nla_len(info->attrs[NL80211_ATTR_MESH_ID]);
-                change = true;
+                if (netif_running(dev))
+                        return -EBUSY;
+
+                wdev_lock(wdev);
+                BUILD_BUG_ON(IEEE80211_MAX_SSID_LEN !=
+                             IEEE80211_MAX_MESH_ID_LEN);
+                wdev->mesh_id_up_len =
+                        nla_len(info->attrs[NL80211_ATTR_MESH_ID]);
+                memcpy(wdev->ssid, nla_data(info->attrs[NL80211_ATTR_MESH_ID]),
+                       wdev->mesh_id_up_len);
+                wdev_unlock(wdev);
         }
 
         if (info->attrs[NL80211_ATTR_4ADDR]) {
@@ -1388,12 +1399,6 @@ static int nl80211_new_interface(struct sk_buff *skb, struct genl_info *info)
             !(rdev->wiphy.interface_modes & (1 << type)))
                 return -EOPNOTSUPP;
 
-        if (type == NL80211_IFTYPE_MESH_POINT &&
-            info->attrs[NL80211_ATTR_MESH_ID]) {
-                params.mesh_id = nla_data(info->attrs[NL80211_ATTR_MESH_ID]);
-                params.mesh_id_len = nla_len(info->attrs[NL80211_ATTR_MESH_ID]);
-        }
-
         if (info->attrs[NL80211_ATTR_4ADDR]) {
                 params.use_4addr = !!nla_get_u8(info->attrs[NL80211_ATTR_4ADDR]);
                 err = nl80211_valid_4addr(rdev, NULL, params.use_4addr, type);
@@ -1410,6 +1415,20 @@ static int nl80211_new_interface(struct sk_buff *skb, struct genl_info *info)
         if (IS_ERR(dev))
                 return PTR_ERR(dev);
 
+        if (type == NL80211_IFTYPE_MESH_POINT &&
+            info->attrs[NL80211_ATTR_MESH_ID]) {
+                struct wireless_dev *wdev = dev->ieee80211_ptr;
+
+                wdev_lock(wdev);
+                BUILD_BUG_ON(IEEE80211_MAX_SSID_LEN !=
+                             IEEE80211_MAX_MESH_ID_LEN);
+                wdev->mesh_id_up_len =
+                        nla_len(info->attrs[NL80211_ATTR_MESH_ID]);
+                memcpy(wdev->ssid, nla_data(info->attrs[NL80211_ATTR_MESH_ID]),
+                       wdev->mesh_id_up_len);
+                wdev_unlock(wdev);
+        }
+
         return 0;
 }
 
@@ -2543,21 +2562,32 @@ static int nl80211_req_set_reg(struct sk_buff *skb, struct genl_info *info)
 }
 
 static int nl80211_get_mesh_params(struct sk_buff *skb,
-        struct genl_info *info)
+                                   struct genl_info *info)
 {
         struct cfg80211_registered_device *rdev = info->user_ptr[0];
-        struct mesh_config cur_params;
-        int err;
         struct net_device *dev = info->user_ptr[1];
+        struct wireless_dev *wdev = dev->ieee80211_ptr;
+        struct mesh_config cur_params;
+        int err = 0;
         void *hdr;
         struct nlattr *pinfoattr;
         struct sk_buff *msg;
 
+        if (wdev->iftype != NL80211_IFTYPE_MESH_POINT)
+                return -EOPNOTSUPP;
+
         if (!rdev->ops->get_mesh_params)
                 return -EOPNOTSUPP;
 
-        /* Get the mesh params */
-        err = rdev->ops->get_mesh_params(&rdev->wiphy, dev, &cur_params);
+        wdev_lock(wdev);
+        /* If not connected, get default parameters */
+        if (!wdev->mesh_id_len)
+                memcpy(&cur_params, &default_mesh_config, sizeof(cur_params));
+        else
+                err = rdev->ops->get_mesh_params(&rdev->wiphy, dev,
+                                                 &cur_params);
+        wdev_unlock(wdev);
+
         if (err)
                 return err;
 
@@ -2705,23 +2735,37 @@ do {\
 #undef FILL_IN_MESH_PARAM_IF_SET
 }
 
-static int nl80211_set_mesh_params(struct sk_buff *skb, struct genl_info *info)
+static int nl80211_update_mesh_params(struct sk_buff *skb,
+                                      struct genl_info *info)
 {
         struct cfg80211_registered_device *rdev = info->user_ptr[0];
         struct net_device *dev = info->user_ptr[1];
+        struct wireless_dev *wdev = dev->ieee80211_ptr;
         struct mesh_config cfg;
         u32 mask;
         int err;
 
-        if (!rdev->ops->set_mesh_params)
+        if (wdev->iftype != NL80211_IFTYPE_MESH_POINT)
+                return -EOPNOTSUPP;
+
+        if (!rdev->ops->update_mesh_params)
                 return -EOPNOTSUPP;
 
         err = nl80211_parse_mesh_params(info, &cfg, &mask);
         if (err)
                 return err;
 
-        /* Apply changes */
-        return rdev->ops->set_mesh_params(&rdev->wiphy, dev, &cfg, mask);
+        wdev_lock(wdev);
+        if (!wdev->mesh_id_len)
+                err = -ENOLINK;
+
+        if (!err)
+                err = rdev->ops->update_mesh_params(&rdev->wiphy, dev,
+                                                    mask, &cfg);
+
+        wdev_unlock(wdev);
+
+        return err;
 }
 
 static int nl80211_get_reg(struct sk_buff *skb, struct genl_info *info)
@@ -4505,6 +4549,41 @@ out:
         return err;
 }
 
+static int nl80211_join_mesh(struct sk_buff *skb, struct genl_info *info)
+{
+        struct cfg80211_registered_device *rdev = info->user_ptr[0];
+        struct net_device *dev = info->user_ptr[1];
+        struct mesh_config cfg;
+        int err;
+
+        /* start with default */
+        memcpy(&cfg, &default_mesh_config, sizeof(cfg));
+
+        if (info->attrs[NL80211_ATTR_MESH_PARAMS]) {
+                /* and parse parameters if given */
+                err = nl80211_parse_mesh_params(info, &cfg, NULL);
+                if (err)
+                        return err;
+        }
+
+        if (!info->attrs[NL80211_ATTR_MESH_ID] ||
+            !nla_len(info->attrs[NL80211_ATTR_MESH_ID]))
+                return -EINVAL;
+
+        return cfg80211_join_mesh(rdev, dev,
+                                  nla_data(info->attrs[NL80211_ATTR_MESH_ID]),
+                                  nla_len(info->attrs[NL80211_ATTR_MESH_ID]),
+                                  &cfg);
+}
+
+static int nl80211_leave_mesh(struct sk_buff *skb, struct genl_info *info)
+{
+        struct cfg80211_registered_device *rdev = info->user_ptr[0];
+        struct net_device *dev = info->user_ptr[1];
+
+        return cfg80211_leave_mesh(rdev, dev);
+}
+
 #define NL80211_FLAG_NEED_WIPHY         0x01
 #define NL80211_FLAG_NEED_NETDEV        0x02
 #define NL80211_FLAG_NEED_RTNL          0x04
@@ -4769,10 +4848,10 @@ static struct genl_ops nl80211_ops[] = {
         },
         {
                 .cmd = NL80211_CMD_SET_MESH_PARAMS,
-                .doit = nl80211_set_mesh_params,
+                .doit = nl80211_update_mesh_params,
                 .policy = nl80211_policy,
                 .flags = GENL_ADMIN_PERM,
-                .internal_flags = NL80211_FLAG_NEED_NETDEV |
+                .internal_flags = NL80211_FLAG_NEED_NETDEV_UP |
                                   NL80211_FLAG_NEED_RTNL,
         },
         {
@@ -4987,6 +5066,22 @@ static struct genl_ops nl80211_ops[] = {
                 .internal_flags = NL80211_FLAG_NEED_NETDEV |
                                   NL80211_FLAG_NEED_RTNL,
         },
+        {
+                .cmd = NL80211_CMD_JOIN_MESH,
+                .doit = nl80211_join_mesh,
+                .policy = nl80211_policy,
+                .flags = GENL_ADMIN_PERM,
+                .internal_flags = NL80211_FLAG_NEED_NETDEV_UP |
+                                  NL80211_FLAG_NEED_RTNL,
+        },
+        {
+                .cmd = NL80211_CMD_LEAVE_MESH,
+                .doit = nl80211_leave_mesh,
+                .policy = nl80211_policy,
+                .flags = GENL_ADMIN_PERM,
+                .internal_flags = NL80211_FLAG_NEED_NETDEV_UP |
+                                  NL80211_FLAG_NEED_RTNL,
+        },
 };
 
 static struct genl_multicast_group nl80211_mlme_mcgrp = {
diff --git a/net/wireless/util.c b/net/wireless/util.c
index fee020b15a4e..4de624ca4c63 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -792,6 +792,7 @@ int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
 
         if (ntype != otype) {
                 dev->ieee80211_ptr->use_4addr = false;
+                dev->ieee80211_ptr->mesh_id_up_len = 0;
 
                 switch (otype) {
                 case NL80211_IFTYPE_ADHOC: