ieee802154: hwsim: Implement address filtering

We have access to the address filters being theoretically applied, we
also have access to the actual filtering level applied, so let's add a
proper frame validation sequence in hwsim.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Alexander Aring <aahringo@redhat.com>
Link: https://lore.kernel.org/r/20221007085310.503366-6-miquel.raynal@bootlin.com
[stefan@datenfreihafen.org: fixup some checkpatch warnings]
Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>

diff --git a/drivers/net/ieee802154/mac802154_hwsim.c b/drivers/net/ieee802154/mac802154_hwsim.c
index 458be66b51959eab3781a98c7ceaa1c47b85ec92..75d802e0b68537eeedb6e1b508561b93c2207e56 100644 (file)
--- a/drivers/net/ieee802154/mac802154_hwsim.c
+++ b/drivers/net/ieee802154/mac802154_hwsim.c
@@ -18,6 +18,7 @@
 #include <linux/netdevice.h>
 #include <linux/device.h>
 #include <linux/spinlock.h>
+#include <net/ieee802154_netdev.h>
 #include <net/mac802154.h>
 #include <net/cfg802154.h>
 #include <net/genetlink.h>
@@ -139,6 +140,112 @@ static int hwsim_hw_addr_filt(struct ieee802154_hw *hw,
        return 0;
 }
 
+static void hwsim_hw_receive(struct ieee802154_hw *hw, struct sk_buff *skb,
+                            u8 lqi)
+{
+       struct ieee802154_hdr hdr;
+       struct hwsim_phy *phy = hw->priv;
+       struct hwsim_pib *pib;
+
+       rcu_read_lock();
+       pib = rcu_dereference(phy->pib);
+
+       if (!pskb_may_pull(skb, 3)) {
+               dev_dbg(hw->parent, "invalid frame\n");
+               goto drop;
+       }
+
+       memcpy(&hdr, skb->data, 3);
+
+       /* Level 4 filtering: Frame fields validity */
+       if (hw->phy->filtering == IEEE802154_FILTERING_4_FRAME_FIELDS) {
+               /* a) Drop reserved frame types */
+               switch (mac_cb(skb)->type) {
+               case IEEE802154_FC_TYPE_BEACON:
+               case IEEE802154_FC_TYPE_DATA:
+               case IEEE802154_FC_TYPE_ACK:
+               case IEEE802154_FC_TYPE_MAC_CMD:
+                       break;
+               default:
+                       dev_dbg(hw->parent, "unrecognized frame type 0x%x\n",
+                               mac_cb(skb)->type);
+                       goto drop;
+               }
+
+               /* b) Drop reserved frame versions */
+               switch (hdr.fc.version) {
+               case IEEE802154_2003_STD:
+               case IEEE802154_2006_STD:
+               case IEEE802154_STD:
+                       break;
+               default:
+                       dev_dbg(hw->parent,
+                               "unrecognized frame version 0x%x\n",
+                               hdr.fc.version);
+                       goto drop;
+               }
+
+               /* c) PAN ID constraints */
+               if ((mac_cb(skb)->dest.mode == IEEE802154_ADDR_LONG ||
+                    mac_cb(skb)->dest.mode == IEEE802154_ADDR_SHORT) &&
+                   mac_cb(skb)->dest.pan_id != pib->filt.pan_id &&
+                   mac_cb(skb)->dest.pan_id != cpu_to_le16(IEEE802154_PANID_BROADCAST)) {
+                       dev_dbg(hw->parent,
+                               "unrecognized PAN ID %04x\n",
+                               le16_to_cpu(mac_cb(skb)->dest.pan_id));
+                       goto drop;
+               }
+
+               /* d1) Short address constraints */
+               if (mac_cb(skb)->dest.mode == IEEE802154_ADDR_SHORT &&
+                   mac_cb(skb)->dest.short_addr != pib->filt.short_addr &&
+                   mac_cb(skb)->dest.short_addr != cpu_to_le16(IEEE802154_ADDR_BROADCAST)) {
+                       dev_dbg(hw->parent,
+                               "unrecognized short address %04x\n",
+                               le16_to_cpu(mac_cb(skb)->dest.short_addr));
+                       goto drop;
+               }
+
+               /* d2) Extended address constraints */
+               if (mac_cb(skb)->dest.mode == IEEE802154_ADDR_LONG &&
+                   mac_cb(skb)->dest.extended_addr != pib->filt.ieee_addr) {
+                       dev_dbg(hw->parent,
+                               "unrecognized long address 0x%016llx\n",
+                               mac_cb(skb)->dest.extended_addr);
+                       goto drop;
+               }
+
+               /* d4) Specific PAN coordinator case (no parent) */
+               if ((mac_cb(skb)->type == IEEE802154_FC_TYPE_DATA ||
+                    mac_cb(skb)->type == IEEE802154_FC_TYPE_MAC_CMD) &&
+                   mac_cb(skb)->dest.mode == IEEE802154_ADDR_NONE) {
+                       dev_dbg(hw->parent,
+                               "relaying is not supported\n");
+                       goto drop;
+               }
+
+               /* e) Beacon frames follow specific PAN ID rules */
+               if (mac_cb(skb)->type == IEEE802154_FC_TYPE_BEACON &&
+                   pib->filt.pan_id != cpu_to_le16(IEEE802154_PANID_BROADCAST) &&
+                   mac_cb(skb)->dest.pan_id != pib->filt.pan_id) {
+                       dev_dbg(hw->parent,
+                               "invalid beacon PAN ID %04x\n",
+                               le16_to_cpu(mac_cb(skb)->dest.pan_id));
+                       goto drop;
+               }
+       }
+
+       rcu_read_unlock();
+
+       ieee802154_rx_irqsafe(hw, skb, lqi);
+
+       return;
+
+drop:
+       rcu_read_unlock();
+       kfree_skb(skb);
+}
+
 static int hwsim_hw_xmit(struct ieee802154_hw *hw, struct sk_buff *skb)
 {
        struct hwsim_phy *current_phy = hw->priv;
@@ -166,8 +273,7 @@ static int hwsim_hw_xmit(struct ieee802154_hw *hw, struct sk_buff *skb)
 
                        einfo = rcu_dereference(e->info);
                        if (newskb)
-                               ieee802154_rx_irqsafe(e->endpoint->hw, newskb,
-                                                     einfo->lqi);
+                               hwsim_hw_receive(e->endpoint->hw, newskb, einfo->lqi);
                }
        }
        rcu_read_unlock();

diff --git a/include/net/ieee802154_netdev.h b/include/net/ieee802154_netdev.h
index d0d188c3294bd68eeaed992f06a5e20ba33a7648..1b82bbafe8c7a7f83583aab0b8586434e9082f15 100644 (file)
--- a/include/net/ieee802154_netdev.h
+++ b/include/net/ieee802154_netdev.h
@@ -69,6 +69,14 @@ struct ieee802154_hdr_fc {
 #endif
 };
 
+enum ieee802154_frame_version {
+       IEEE802154_2003_STD,
+       IEEE802154_2006_STD,
+       IEEE802154_STD,
+       IEEE802154_RESERVED_STD,
+       IEEE802154_MULTIPURPOSE_STD = IEEE802154_2003_STD,
+};
+
 struct ieee802154_hdr {
        struct ieee802154_hdr_fc fc;
        u8 seq;