ieee820154: add short_addr setting support

This patch adds support for setting short address via nl802154 framework.
Also added a comment because a 0xffff seems to be valid address that we
don't have a short address. This is a valid setting but we need
more checks in upper layers to don't allow this address as source address.
Also the current netlink interface doesn't allow to set the short_addr
to 0xffff. Same for the 0xfffe short address which describes a not
allocated short address.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

3 files changed, 64 insertions, 0 deletions

diff --git a/net/ieee802154/nl802154.c b/net/ieee802154/nl802154.c
index 88cd1293283a..2978c1a78017 100644
--- a/net/ieee802154/nl802154.c
+++ b/net/ieee802154/nl802154.c
@@ -593,6 +593,29 @@ static int nl802154_set_pan_id(struct sk_buff *skb, struct genl_info *info)
         return rdev_set_pan_id(rdev, wpan_dev, pan_id);
 }
 
+static int nl802154_set_short_addr(struct sk_buff *skb, struct genl_info *info)
+{
+        struct cfg802154_registered_device *rdev = info->user_ptr[0];
+        struct net_device *dev = info->user_ptr[1];
+        struct wpan_dev *wpan_dev = dev->ieee802154_ptr;
+        u16 short_addr;
+
+        /* conflict here while tx/rx calls */
+        if (netif_running(dev))
+                return -EBUSY;
+
+        /* don't change address fields on monitor */
+        if (wpan_dev->iftype == NL802154_IFTYPE_MONITOR)
+                return -EINVAL;
+
+        if (!info->attrs[NL802154_ATTR_SHORT_ADDR])
+                return -EINVAL;
+
+        short_addr = nla_get_u16(info->attrs[NL802154_ATTR_SHORT_ADDR]);
+
+        return rdev_set_short_addr(rdev, wpan_dev, short_addr);
+}
+
 #define NL802154_FLAG_NEED_WPAN_PHY     0x01
 #define NL802154_FLAG_NEED_NETDEV       0x02
 #define NL802154_FLAG_NEED_RTNL         0x04
@@ -719,6 +742,14 @@ static const struct genl_ops nl802154_ops[] = {
                 .internal_flags = NL802154_FLAG_NEED_NETDEV |
                                   NL802154_FLAG_NEED_RTNL,
         },
+        {
+                .cmd = NL802154_CMD_SET_SHORT_ADDR,
+                .doit = nl802154_set_short_addr,
+                .policy = nl802154_policy,
+                .flags = GENL_ADMIN_PERM,
+                .internal_flags = NL802154_FLAG_NEED_NETDEV |
+                                  NL802154_FLAG_NEED_RTNL,
+        },
 };
 
 /* initialisation/exit functions */
diff --git a/net/ieee802154/rdev-ops.h b/net/ieee802154/rdev-ops.h
index 4115ea264fd5..16b0de06c3af 100644
--- a/net/ieee802154/rdev-ops.h
+++ b/net/ieee802154/rdev-ops.h
@@ -34,4 +34,11 @@ rdev_set_pan_id(struct cfg802154_registered_device *rdev,
         return rdev->ops->set_pan_id(&rdev->wpan_phy, wpan_dev, pan_id);
 }
 
+static inline int
+rdev_set_short_addr(struct cfg802154_registered_device *rdev,
+                    struct wpan_dev *wpan_dev, u16 short_addr)
+{
+        return rdev->ops->set_short_addr(&rdev->wpan_phy, wpan_dev, short_addr);
+}
+
 #endif /* __CFG802154_RDEV_OPS */
diff --git a/net/mac802154/cfg.c b/net/mac802154/cfg.c
index db6e5e981a83..df29976d1321 100644
--- a/net/mac802154/cfg.c
+++ b/net/mac802154/cfg.c
@@ -83,9 +83,35 @@ static int ieee802154_set_pan_id(struct wpan_phy *wpan_phy,
         return 0;
 }
 
+static int
+ieee802154_set_short_addr(struct wpan_phy *wpan_phy, struct wpan_dev *wpan_dev,
+                          const u16 short_addr)
+{
+        ASSERT_RTNL();
+
+        /* TODO
+         * I am not sure about to check here on broadcast short_addr.
+         * Broadcast is a valid setting, comment from 802.15.4:
+         * A value of 0xfffe indicates that the device has
+         * associated but has not been allocated an address. A
+         * value of 0xffff indicates that the device does not
+         * have a short address.
+         *
+         * I think we should allow to set these settings but
+         * don't allow to allow socket communication with it.
+         */
+        if (short_addr == IEEE802154_ADDR_SHORT_UNSPEC ||
+            short_addr == IEEE802154_ADDR_SHORT_BROADCAST)
+                return -EINVAL;
+
+        wpan_dev->short_addr = cpu_to_le16(short_addr);
+        return 0;
+}
+
 const struct cfg802154_ops mac802154_config_ops = {
         .add_virtual_intf_deprecated = ieee802154_add_iface_deprecated,
         .del_virtual_intf_deprecated = ieee802154_del_iface_deprecated,
         .set_channel = ieee802154_set_channel,
         .set_pan_id = ieee802154_set_pan_id,
+        .set_short_addr = ieee802154_set_short_addr,
 };