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tipc: move received discovery data evaluation inside node.c

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The node lock is currently grabbed and and released in the function
tipc_disc_rcv() in the file discover.c. As a preparation for the next
commits, we need to move this node lock handling, along with the code
area it is covering, to node.c.

This commit introduces this change.

Tested-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jon Paul Maloy
2015-07-30 18:24:22 -04:00
committed by David S. Miller
parent 662921cd0a
commit cf148816ac
3 changed files with 127 additions and 123 deletions
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116
net/tipc/discover.c
View File

@@ -120,29 +120,24 @@ static void disc_dupl_alert(struct tipc_bearer *b_ptr, u32 node_addr,
* @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)
@@ -164,91 +159,20 @@ void tipc_disc_rcv(struct net *net, struct sk_buff *buf,
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);
}
/**