When SetNodeTags changed a node's tags, the node's self view wasn't
updated. The bug manifested as: the first SetNodeTags call updates
the server but the client's self view doesn't update until a second
call with the same tag.
Root cause: Three issues combined to prevent self-updates:
1. SetNodeTags returned PolicyChange which doesn't set OriginNode,
so the mapper's self-update check failed.
2. The Change.Merge function didn't preserve OriginNode, so when
changes were batched together, OriginNode was lost.
3. generateMapResponse checked OriginNode only in buildFromChange(),
but PolicyChange uses RequiresRuntimePeerComputation which
bypasses that code path entirely and calls policyChangeResponse()
instead.
The fix addresses all three:
- state.go: Set OriginNode on the returned change
- change.go: Preserve OriginNode (and TargetNode) during merge
- batcher.go: Pass isSelfUpdate to policyChangeResponse so the
origin node gets both self info AND packet filters
- mapper.go: Add includeSelf parameter to policyChangeResponse
Fixes#2978
This commit replaces the ChangeSet with a simpler bool based
change model that can be directly used in the map builder to
build the appropriate map response based on the change that
has occured. Previously, we fell back to sending full maps
for a lot of changes as that was consider "the safe" thing to
do to ensure no updates were missed.
This was slightly problematic as a node that already has a list
of peers will only do full replacement of the peers if the list
is non-empty, meaning that it was not possible to remove all
nodes (if for example policy changed).
Now we will keep track of last seen nodes, so we can send remove
ids, but also we are much smarter on how we send smaller, partial
maps when needed.
Fixes#2389
Signed-off-by: Kristoffer Dalby <kristoffer@dalby.cc>
Initial work on a nodestore which stores all of the nodes
and their relations in memory with relationship for peers
precalculated.
It is a copy-on-write structure, replacing the "snapshot"
when a change to the structure occurs. It is optimised for reads,
and while batches are not fast, they are grouped together
to do less of the expensive peer calculation if there are many
changes rapidly.
Writes will block until commited, while reads are never
blocked.
Signed-off-by: Kristoffer Dalby <kristoffer@tailscale.com>
