* @buf: buffer containing message
* @bearer: bearer that message arrived on
*/
-void tipc_disc_rcv(struct net *net, struct sk_buff *buf,
+void tipc_disc_rcv(struct net *net, struct sk_buff *skb,
struct tipc_bearer *bearer)
{
struct tipc_net *tn = net_generic(net, tipc_net_id);
- struct tipc_node *node;
struct tipc_media_addr maddr;
- struct sk_buff *rbuf;
- struct tipc_msg *msg = buf_msg(buf);
- u32 ddom = msg_dest_domain(msg);
- u32 onode = msg_prevnode(msg);
- u32 net_id = msg_bc_netid(msg);
- u32 mtyp = msg_type(msg);
- u32 signature = msg_node_sig(msg);
- u16 caps = msg_node_capabilities(msg);
- bool addr_match = false;
- bool sign_match = false;
- bool link_up = false;
- bool accept_addr = false;
- bool accept_sign = false;
+ struct sk_buff *rskb;
+ struct tipc_msg *hdr = buf_msg(skb);
+ u32 ddom = msg_dest_domain(hdr);
+ u32 onode = msg_prevnode(hdr);
+ u32 net_id = msg_bc_netid(hdr);
+ u32 mtyp = msg_type(hdr);
+ u32 signature = msg_node_sig(hdr);
+ u16 caps = msg_node_capabilities(hdr);
bool respond = false;
+ bool dupl_addr = false;
- bearer->media->msg2addr(bearer, &maddr, msg_media_addr(msg));
- kfree_skb(buf);
+ bearer->media->msg2addr(bearer, &maddr, msg_media_addr(hdr));
+ kfree_skb(skb);
/* Ensure message from node is valid and communication is permitted */
if (net_id != tn->net_id)
if (!tipc_in_scope(bearer->domain, onode))
return;
- node = tipc_node_create(net, onode);
- if (!node)
- return;
- tipc_node_lock(node);
- node->capabilities = caps;
-
- /* Prepare to validate requesting node's signature and media address */
- sign_match = (signature == node->signature);
- tipc_node_check_dest(node, bearer, &link_up, &addr_match, &maddr);
-
- /* These three flags give us eight permutations: */
-
- if (sign_match && addr_match && link_up) {
- /* All is fine. Do nothing. */
- } else if (sign_match && addr_match && !link_up) {
- /* Respond. The link will come up in due time */
- respond = true;
- } else if (sign_match && !addr_match && link_up) {
- /* Peer has changed i/f address without rebooting.
- * If so, the link will reset soon, and the next
- * discovery will be accepted. So we can ignore it.
- * It may also be an cloned or malicious peer having
- * chosen the same node address and signature as an
- * existing one.
- * Ignore requests until the link goes down, if ever.
- */
+ tipc_node_check_dest(net, onode, bearer, caps, signature,
+ &maddr, &respond, &dupl_addr);
+ if (dupl_addr)
disc_dupl_alert(bearer, onode, &maddr);
- } else if (sign_match && !addr_match && !link_up) {
- /* Peer link has changed i/f address without rebooting.
- * It may also be a cloned or malicious peer; we can't
- * distinguish between the two.
- * The signature is correct, so we must accept.
- */
- accept_addr = true;
- respond = true;
- } else if (!sign_match && addr_match && link_up) {
- /* Peer node rebooted. Two possibilities:
- * - Delayed re-discovery; this link endpoint has already
- * reset and re-established contact with the peer, before
- * receiving a discovery message from that node.
- * (The peer happened to receive one from this node first).
- * - The peer came back so fast that our side has not
- * discovered it yet. Probing from this side will soon
- * reset the link, since there can be no working link
- * endpoint at the peer end, and the link will re-establish.
- * Accept the signature, since it comes from a known peer.
- */
- accept_sign = true;
- } else if (!sign_match && addr_match && !link_up) {
- /* The peer node has rebooted.
- * Accept signature, since it is a known peer.
- */
- accept_sign = true;
- respond = true;
- } else if (!sign_match && !addr_match && link_up) {
- /* Peer rebooted with new address, or a new/duplicate peer.
- * Ignore until the link goes down, if ever.
- */
- disc_dupl_alert(bearer, onode, &maddr);
- } else if (!sign_match && !addr_match && !link_up) {
- /* Peer rebooted with new address, or it is a new peer.
- * Accept signature and address.
- */
- accept_sign = true;
- accept_addr = true;
- respond = true;
- }
-
- if (accept_sign)
- node->signature = signature;
-
- if (accept_addr && !tipc_node_update_dest(node, bearer, &maddr))
- respond = false;
/* Send response, if necessary */
if (respond && (mtyp == DSC_REQ_MSG)) {
- rbuf = tipc_buf_acquire(MAX_H_SIZE);
- if (rbuf) {
- tipc_disc_init_msg(net, rbuf, DSC_RESP_MSG, bearer);
- tipc_bearer_send(net, bearer->identity, rbuf, &maddr);
- kfree_skb(rbuf);
+ rskb = tipc_buf_acquire(MAX_H_SIZE);
+ if (rskb) {
+ tipc_disc_init_msg(net, rskb, DSC_RESP_MSG, bearer);
+ tipc_bearer_send(net, bearer->identity, rskb, &maddr);
+ kfree_skb(rskb);
}
}
- tipc_node_unlock(node);
- tipc_node_put(node);
}
/**
projects / cascardo / linux.git / blobdiff