In a situation where the mesh gateway is configured to bind to multiple
network interfaces, we use a feature called 'tagged addresses'.
Sometimes an address is duplicated across multiple tags such as 'lan'
and 'lan_ipv4'.
There is code to deduplicate these things when creating envoy listeners,
but that code doesn't ensure that the same tag wins every time. If the
winning tag flaps between xDS discovery requests it will cause the
listener to be drained and replaced.
This PR updates the tags that we generate for Envoy stats.
Several of these come with breaking changes, since we can't keep two stats prefixes for a filter.
Extend Consul’s intentions model to allow for request-based access control enforcement for HTTP-like protocols in addition to the existing connection-based enforcement for unspecified protocols (e.g. tcp).
- Upgrade the ConfigEntry.ListAll RPC to be kind-aware so that older
copies of consul will not see new config entries it doesn't understand
replicate down.
- Add shim conversion code so that the old API/CLI method of interacting
with intentions will continue to work so long as none of these are
edited via config entry endpoints. Almost all of the read-only APIs will
continue to function indefinitely.
- Add new APIs that operate on individual intentions without IDs so that
the UI doesn't need to implement CAS operations.
- Add a new serf feature flag indicating support for
intentions-as-config-entries.
- The old line-item intentions way of interacting with the state store
will transparently flip between the legacy memdb table and the config
entry representations so that readers will never see a hiccup during
migration where the results are incomplete. It uses a piece of system
metadata to control the flip.
- The primary datacenter will begin migrating intentions into config
entries on startup once all servers in the datacenter are on a version
of Consul with the intentions-as-config-entries feature flag. When it is
complete the old state store representations will be cleared. We also
record a piece of system metadata indicating this has occurred. We use
this metadata to skip ALL of this code the next time the leader starts
up.
- The secondary datacenters continue to run the old intentions
replicator until all servers in the secondary DC and primary DC support
intentions-as-config-entries (via serf flag). Once this condition it met
the old intentions replicator ceases.
- The secondary datacenters replicate the new config entries as they are
migrated in the primary. When they detect that the primary has zeroed
it's old state store table it waits until all config entries up to that
point are replicated and then zeroes its own copy of the old state store
table. We also record a piece of system metadata indicating this has
occurred. We use this metadata to skip ALL of this code the next time
the leader starts up.
Fixes#8466
Since Consul 1.8.0 there was a bug in how ingress gateway protocol
compatibility was enforced. At the point in time that an ingress-gateway
config entry was modified the discovery chain for each upstream was
checked to ensure the ingress gateway protocol matched. Unfortunately
future modifications of other config entries were not validated against
existing ingress-gateway definitions, such as:
1. create tcp ingress-gateway pointing to 'api' (ok)
2. create service-defaults for 'api' setting protocol=http (worked, but not ok)
3. create service-splitter or service-router for 'api' (worked, but caused an agent panic)
If you were to do these in a different order, it would fail without a
crash:
1. create service-defaults for 'api' setting protocol=http (ok)
2. create service-splitter or service-router for 'api' (ok)
3. create tcp ingress-gateway pointing to 'api' (fail with message about
protocol mismatch)
This PR introduces the missing validation. The two new behaviors are:
1. create tcp ingress-gateway pointing to 'api' (ok)
2. (NEW) create service-defaults for 'api' setting protocol=http ("ok" for back compat)
3. (NEW) create service-splitter or service-router for 'api' (fail with
message about protocol mismatch)
In consideration for any existing users that may be inadvertently be
falling into item (2) above, that is now officiall a valid configuration
to be in. For anyone falling into item (3) above while you cannot use
the API to manufacture that scenario anymore, anyone that has old (now
bad) data will still be able to have the agent use them just enough to
generate a new agent/proxycfg error message rather than a panic.
Unfortunately we just don't have enough information to properly fix the
config entries.
Related changes:
- hard-fail the xDS connection attempt if the envoy version is known to be too old to be supported
- remove the RouterMatchSafeRegex proxy feature since all supported envoy versions have it
- stop using --max-obj-name-len (due to: envoyproxy/envoy#11740)
A port can be sent in the Host header as defined in the HTTP RFC, so we
take any hosts that we want to match traffic to and also add another
host with the listener port added.
Also fix an issue with envoy integration tests not running the
case-ingress-gateway-tls test.
Co-authored-by: Matt Keeler <mkeeler@users.noreply.github.com>
Currently when passing hostname clusters to Envoy, we set each service instance registered with Consul as an LbEndpoint for the cluster.
However, Envoy can only handle one per cluster:
[2020-06-04 18:32:34.094][1][warning][config] [source/common/config/grpc_subscription_impl.cc:87] gRPC config for type.googleapis.com/envoy.api.v2.Cluster rejected: Error adding/updating cluster(s) dc2.internal.ddd90499-9b47-91c5-4616-c0cbf0fc358a.consul: LOGICAL_DNS clusters must have a single locality_lb_endpoint and a single lb_endpoint, server.dc2.consul: LOGICAL_DNS clusters must have a single locality_lb_endpoint and a single lb_endpoint
Envoy is currently handling this gracefully by only picking one of the endpoints. However, we should avoid passing multiple to avoid these warning logs.
This PR:
* Ensures we only pass one endpoint, which is tied to one service instance.
* We prefer sending an endpoint which is marked as Healthy by Consul.
* If no endpoints are healthy we emit a warning and skip the cluster.
* If multiple unique hostnames are spread across service instances we emit a warning and let the user know which will be resolved.
Currently opaque config blocks (config entries, and CA provider config) are
modified by PatchSliceOfMaps, making it impossible for these opaque
config sections to contain slices of maps.
In order to fix this problem, any lazy-decoding of these blocks needs to support
weak decoding of []map[string]interface{} to a struct type before
PatchSliceOfMaps is replaces. This is necessary because these config
blobs are persisted, and during an upgrade an older version of Consul
could read one of the new configuration values, which would cause an error.
To support the upgrade path, this commit first introduces the new hooks
for weak decoding of []map[string]interface{} and uses them only in the
lazy-decode paths. That way, in a future release, new style
configuration will be supported by the older version of Consul.
This decode hook has a number of advantages:
1. It no longer panics. It allows mapstructure to report the error
2. It no longer requires the user to declare which fields are slices of
structs. It can deduce that information from the 'to' value.
3. It will make it possible to preserve opaque configuration, allowing
for structured opaque config.
Previously, we did not require the 'service-name.*' host header value
when on a single http service was exposed. However, this allows a user
to get into a situation where, if they add another service to the
listener, suddenly the previous service's traffic might not be routed
correctly. Thus, we always require the Host header, even if there is
only 1 service.
Also, we add the make the default domain matching more restrictive by
matching "service-name.ingress.*" by default. This lines up better with
the namespace case and more accurately matches the Consul DNS value we
expect people to use in this case.
The DNS resolution will be handled by Envoy and defaults to LOGICAL_DNS. This discovery type can be overridden on a per-gateway basis with the envoy_dns_discovery_type Gateway Option.
If a service contains an instance with a hostname as an address we set the Envoy cluster to use DNS as the discovery type rather than EDS. Since both mesh gateways and terminating gateways route to clusters using SNI, whenever there is a mix of hostnames and IP addresses associated with a service we use the hostname + CDS rather than the IPs + EDS.
Note that we detect hostnames by attempting to parse the service instance's address as an IP. If it is not a valid IP we assume it is a hostname.