mac802154: Follow the number of associated devices

Track the count of associated devices. Limit the number of associations
using the value provided by the user if any. If we reach the maximum
number of associations, we tell the device we are at capacity. If the
user do not want to accept any more associations, it may specify the
value 0 to the maximum number of associations, which will lead to an
access denied error status returned to the peers trying to associate.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Acked-by: Alexander Aring <aahringo@redhat.com>
Link: https://lore.kernel.org/linux-wpan/20230927181214.129346-10-miquel.raynal@bootlin.com
This commit is contained in:
Miquel Raynal 2023-09-27 20:12:12 +02:00
parent ce93b9378c
commit 80f8bf9a2a
4 changed files with 27 additions and 10 deletions

View File

@ -507,6 +507,7 @@ struct wpan_dev {
struct ieee802154_pan_device *parent;
struct list_head children;
unsigned int max_associations;
unsigned int nchildren;
};
#define to_phy(_dev) container_of(_dev, struct wpan_phy, dev)

View File

@ -212,6 +212,8 @@ static void cfg802154_free_peer_structures(struct wpan_dev *wpan_dev)
kfree(child);
}
wpan_dev->nchildren = 0;
mutex_unlock(&wpan_dev->association_lock);
}

View File

@ -454,6 +454,7 @@ static int mac802154_disassociate_child(struct wpan_phy *wpan_phy,
return ret;
list_del(&child->node);
wpan_dev->nchildren--;
kfree(child);
return 0;

View File

@ -800,20 +800,32 @@ int mac802154_process_association_req(struct ieee802154_sub_if_data *sdata,
child->mode = IEEE802154_EXTENDED_ADDRESSING;
ceaddr = swab64((__force u64)child->extended_addr);
assoc_resp_pl.status = IEEE802154_ASSOCIATION_SUCCESSFUL;
if (assoc_req_pl.alloc_addr) {
assoc_resp_pl.short_addr = cfg802154_get_free_short_addr(wpan_dev);
child->mode = IEEE802154_SHORT_ADDRESSING;
if (wpan_dev->nchildren >= wpan_dev->max_associations) {
if (!wpan_dev->max_associations)
assoc_resp_pl.status = IEEE802154_PAN_ACCESS_DENIED;
else
assoc_resp_pl.status = IEEE802154_PAN_AT_CAPACITY;
assoc_resp_pl.short_addr = cpu_to_le16(IEEE802154_ADDR_SHORT_BROADCAST);
dev_dbg(&sdata->dev->dev,
"Refusing ASSOC REQ from child %8phC, %s\n", &ceaddr,
assoc_resp_pl.status == IEEE802154_PAN_ACCESS_DENIED ?
"access denied" : "too many children");
} else {
assoc_resp_pl.short_addr = cpu_to_le16(IEEE802154_ADDR_SHORT_UNSPEC);
assoc_resp_pl.status = IEEE802154_ASSOCIATION_SUCCESSFUL;
if (assoc_req_pl.alloc_addr) {
assoc_resp_pl.short_addr = cfg802154_get_free_short_addr(wpan_dev);
child->mode = IEEE802154_SHORT_ADDRESSING;
} else {
assoc_resp_pl.short_addr = cpu_to_le16(IEEE802154_ADDR_SHORT_UNSPEC);
}
child->short_addr = assoc_resp_pl.short_addr;
dev_dbg(&sdata->dev->dev,
"Accepting ASSOC REQ from child %8phC, providing short address 0x%04x\n",
&ceaddr, le16_to_cpu(child->short_addr));
}
child->short_addr = assoc_resp_pl.short_addr;
dev_dbg(&sdata->dev->dev,
"Accepting ASSOC REQ from child %8phC, providing short address 0x%04x\n",
&ceaddr, le16_to_cpu(child->short_addr));
ret = mac802154_send_association_resp_locked(sdata, child, &assoc_resp_pl);
if (ret) {
if (ret || assoc_resp_pl.status != IEEE802154_ASSOCIATION_SUCCESSFUL) {
kfree(child);
goto unlock;
}
@ -834,6 +846,7 @@ int mac802154_process_association_req(struct ieee802154_sub_if_data *sdata,
}
list_add(&child->node, &wpan_dev->children);
wpan_dev->nchildren++;
unlock:
mutex_unlock(&wpan_dev->association_lock);