A recent change in Babel causes ifaces to disappear after
reconfiguration. The patch fixes that.
Thanks to Johannes Kimmel for an insightful bugreport.
Alignment of slabs should be at least sizeof(ptr) to avoid unaligned
pointers in slab structures. Fixme: Use proper way to choose alignment
for internal allocators.
After switching to 16-way tries, trie format ignored unaligned / internal
prefixes and only reported the primary prefix of a trie node.
Fix trie format by showing internal prefixes based on the 'local' bitmask
of a node. Also do basic (intra-node) reconstruction of prefix patterns
by finding common subtrees in 'local' bitmask.
In future, we could improve that by doing inter-node reconstruction, so
prefixes entered as one pattern for a subtree (e.g. 192.168.0.0/18+)
would be reported as such, like with aligned prefixes.
The prune loop may may rebuild the prefix trie and therefore invalidate
walk state for asynchronous walks (used in 'show route in' cmd). Fix it
by adding locking that keeps the old trie in memory until current walks
are done.
In future this could be improved by rebuilding trie walk states (by
lookup for last found prefix) after the prefix trie rebuild.
When rtable is pruned and network fib nodes are removed, we also need to
prune prefix trie. Unfortunately, rebuilding prefix trie takes long time
(got about 400 ms for 1M networks), so must not be atomic, we have to
rebuild a new trie while current one is still active. That may require
some considerable amount of temporary memory, so we do that only if
we expect significant trie size reduction.
Implement flowspec validation procedure as described in RFC 8955 sec. 6
and RFC 9117. The Validation procedure enforces that only routers in the
forwarding path for a network can originate flowspec rules for that
network.
The patch adds new mechanism for tracking inter-table dependencies, which
is necessary as the flowspec validation depends on IP routes, and flowspec
rules must be revalidated when best IP routes change.
The validation procedure is disabled by default and requires that
relevant IP table uses trie, as it uses interval queries for subnets.
