• Allan Stephens's avatar
    tipc: Detect duplicate nodes using different network interfaces · 97878a40
    Allan Stephens authored
    Utilizes the new "node signature" field in neighbor discovery messages
    to ensure that all links TIPC associates with a given <Z.C.N> network
    address belong to the same neighboring node. (Previously, TIPC could not
    tell if link setup requests arriving on different interfaces were from
    the same node or from two different nodes that has mistakenly been assigned
    the same network address.)
    The revised algorithm for detecting a duplicate node considers both the
    node signature and the network interface adddress specified in a request
    message when deciding how to respond to a link setup request. This prevents
    false alarms that might otherwise arise during normal network operation
    under the following scenarios:
    a) A neighboring node reboots. (The node's signature changes, but the
    network interface address remains unchanged.)
    b) A neighboring node's network interface is replaced. (The node's signature
    remains unchanged, but the network interface address changes.)
    c) A neighboring node is completely replaced. (The node's signature and
    network interface address both change.)
    The algorithm also handles cases in which a node reboots and re-establishes
    its links to TIPC (or begins re-establishing those links) before TIPC
    detects that it is using a new node signature. In such cases of "delayed
    rediscovery" TIPC simply accepts the new signature without disrupting
    communication that is already underway over the links.
    Thanks to Laser [gotolaser@gmail.com] for his contributions to the
    development of this enhancement.
    Signed-off-by: default avatarAllan Stephens <allan.stephens@windriver.com>
    Signed-off-by: default avatarPaul Gortmaker <paul.gortmaker@windriver.com>