From: Jon Paul Maloy Date: Thu, 30 Jul 2015 22:24:22 +0000 (-0400) Subject: tipc: move received discovery data evaluation inside node.c X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=cf148816acb6def45474001302368eb472995e62;p=linux-beck.git tipc: move received discovery data evaluation inside node.c 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 Signed-off-by: Jon Maloy Signed-off-by: David S. Miller --- diff --git a/net/tipc/discover.c b/net/tipc/discover.c index 164d08907d6f..d14e0a4aa9af 100644 --- a/net/tipc/discover.c +++ b/net/tipc/discover.c @@ -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); } /** diff --git a/net/tipc/node.c b/net/tipc/node.c index a3ceeda2a80a..d03e88f2273b 100644 --- a/net/tipc/node.c +++ b/net/tipc/node.c @@ -138,7 +138,7 @@ struct tipc_node *tipc_node_find(struct net *net, u32 addr) return NULL; } -struct tipc_node *tipc_node_create(struct net *net, u32 addr) +struct tipc_node *tipc_node_create(struct net *net, u32 addr, u16 capabilities) { struct tipc_net *tn = net_generic(net, tipc_net_id); struct tipc_node *n_ptr, *temp_node; @@ -154,6 +154,7 @@ struct tipc_node *tipc_node_create(struct net *net, u32 addr) } n_ptr->addr = addr; n_ptr->net = net; + n_ptr->capabilities = capabilities; kref_init(&n_ptr->kref); spin_lock_init(&n_ptr->lock); INIT_HLIST_NODE(&n_ptr->hash); @@ -422,38 +423,118 @@ bool tipc_node_is_up(struct tipc_node *n) return n->active_links[0] != INVALID_BEARER_ID; } -void tipc_node_check_dest(struct tipc_node *n, struct tipc_bearer *b, - bool *link_up, bool *addr_match, - struct tipc_media_addr *maddr) +void tipc_node_check_dest(struct net *net, u32 onode, + struct tipc_bearer *b, + u16 capabilities, u32 signature, + struct tipc_media_addr *maddr, + bool *respond, bool *dupl_addr) { - struct tipc_link *l = n->links[b->identity].link; - struct tipc_media_addr *curr = &n->links[b->identity].maddr; + struct tipc_node *n; + struct tipc_link *l; + struct tipc_media_addr *curr_maddr; + struct sk_buff_head *inputq; + bool addr_match = false; + bool sign_match = false; + bool link_up = false; + bool accept_addr = false; + + *dupl_addr = false; + *respond = false; + + n = tipc_node_create(net, onode, capabilities); + if (!n) + return; - *link_up = l && tipc_link_is_up(l); - *addr_match = l && !memcmp(curr, maddr, sizeof(*maddr)); -} + tipc_node_lock(n); -bool tipc_node_update_dest(struct tipc_node *n, struct tipc_bearer *b, - struct tipc_media_addr *maddr) -{ - struct tipc_link *l = n->links[b->identity].link; - struct tipc_media_addr *curr = &n->links[b->identity].maddr; - struct sk_buff_head *inputq = &n->links[b->identity].inputq; + curr_maddr = &n->links[b->identity].maddr; + inputq = &n->links[b->identity].inputq; + + /* Prepare to validate requesting node's signature and media address */ + l = n->links[b->identity].link; + link_up = l && tipc_link_is_up(l); + addr_match = l && !memcmp(curr_maddr, maddr, sizeof(*maddr)); + sign_match = (signature == n->signature); + + /* 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. + */ + *dupl_addr = true; + } 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. + */ + n->signature = signature; + } else if (!sign_match && addr_match && !link_up) { + /* The peer node has rebooted. + * Accept signature, since it is a known peer. + */ + n->signature = signature; + *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. + */ + *dupl_addr = true; + } else if (!sign_match && !addr_match && !link_up) { + /* Peer rebooted with new address, or it is a new peer. + * Accept signature and address. + */ + n->signature = signature; + accept_addr = true; + *respond = true; + } + + if (!accept_addr) + goto exit; + /* Now create new link if not already existing */ if (!l) { l = tipc_link_create(n, b, maddr, inputq, &n->bclink.namedq); - if (!l) - return false; + if (!l) { + *respond = false; + goto exit; + } tipc_node_calculate_timer(n, l); - if (n->link_cnt == 1) { + if (n->link_cnt == 1) if (!mod_timer(&n->timer, jiffies + n->keepalive_intv)) tipc_node_get(n); - } } memcpy(&l->media_addr, maddr, sizeof(*maddr)); - memcpy(curr, maddr, sizeof(*maddr)); + memcpy(curr_maddr, maddr, sizeof(*maddr)); tipc_node_link_down(n, b->identity); - return true; +exit: + tipc_node_unlock(n); + tipc_node_put(n); } void tipc_node_delete_links(struct net *net, int bearer_id) diff --git a/net/tipc/node.h b/net/tipc/node.h index 406c6fe0dbb2..9a977467fc46 100644 --- a/net/tipc/node.h +++ b/net/tipc/node.h @@ -147,13 +147,12 @@ struct tipc_node { struct tipc_node *tipc_node_find(struct net *net, u32 addr); void tipc_node_put(struct tipc_node *node); -struct tipc_node *tipc_node_create(struct net *net, u32 addr); void tipc_node_stop(struct net *net); -void tipc_node_check_dest(struct tipc_node *n, struct tipc_bearer *bearer, - bool *link_up, bool *addr_match, - struct tipc_media_addr *maddr); -bool tipc_node_update_dest(struct tipc_node *n, struct tipc_bearer *bearer, - struct tipc_media_addr *maddr); +void tipc_node_check_dest(struct net *net, u32 onode, + struct tipc_bearer *bearer, + u16 capabilities, u32 signature, + struct tipc_media_addr *maddr, + bool *respond, bool *dupl_addr); void tipc_node_delete_links(struct net *net, int bearer_id); void tipc_node_attach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr); void tipc_node_detach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr);