Fix numerous go-getter security issues:
- Add timeouts to http, git, and hg operations to prevent DoS
- Add size limit to http to prevent resource exhaustion
- Disable following symlinks in both artifacts and `job run`
- Stop performing initial HEAD request to avoid file corruption on
retries and DoS opportunities.
**Approach**
Since Nomad has no ability to differentiate a DoS-via-large-artifact vs
a legitimate workload, all of the new limits are configurable at the
client agent level.
The max size of HTTP downloads is also exposed as a node attribute so
that if some workloads have large artifacts they can specify a high
limit in their jobspecs.
In the future all of this plumbing could be extended to enable/disable
specific getters or artifact downloading entirely on a per-node basis.
This change modifies the template task runner to utilise the
new consul-template which includes Nomad service lookup template
funcs.
In order to provide security and auth to consul-template, we use
a custom HTTP dialer which is passed to consul-template when
setting up the runner. This method follows Vault implementation.
Co-authored-by: Michael Schurter <mschurter@hashicorp.com>
Nomad inherited protocol version numbering configuration from Consul and
Serf, but unlike those projects Nomad has never used it. Nomad's
`protocol_version` has always been `1`.
While the code is effectively unused and therefore poses no runtime
risks to leave, I felt like removing it was best because:
1. Nomad's RPC subsystem has been able to evolve extensively without
needing to increment the version number.
2. Nomad's HTTP API has evolved extensively without increment
`API{Major,Minor}Version`. If we want to version the HTTP API in the
future, I doubt this is the mechanism we would choose.
3. The presence of the `server.protocol_version` configuration
parameter is confusing since `server.raft_protocol` *is* an important
parameter for operators to consider. Even more confusing is that
there is a distinct Serf protocol version which is included in `nomad
server members` output under the heading `Protocol`. `raft_protocol`
is the *only* protocol version relevant to Nomad developers and
operators. The other protocol versions are either deadcode or have
never changed (Serf).
4. If we were to need to version the RPC, HTTP API, or Serf protocols, I
don't think these configuration parameters and variables are the best
choice. If we come to that point we should choose a versioning scheme
based on the use case and modern best practices -- not this 6+ year
old dead code.
Log the failure error when the agent fails to start. Previously, the
agent startup failure error would be emitted to the command UI but not
logged. So it doesn't get emitted to syslog or `log_file` if they are
set, and it makes debugging much harder. Also, logging the error again
before exit makes the error more visible: previously, the operator
needed to scroll to the top to find the error.
On a sample failure, the output will look like:
```
==> WARNING: Bootstrap mode enabled! Potentially unsafe operation.
==> Loaded configuration from sample-configs/config-bad
==> Starting Nomad agent...
==> Error starting agent: setting up server node ID failed: mkdir /path-without-permission: read-only file system
2021-10-20T14:38:51.179-0400 [WARN] agent.plugin_loader: skipping external plugins since plugin_dir doesn't exist: plugin_dir=/path-without-permission/plugins
2021-10-20T14:38:51.181-0400 [DEBUG] agent.plugin_loader.docker: using client connection initialized from environment: plugin_dir=/path-without-permission/plugins
2021-10-20T14:38:51.181-0400 [DEBUG] agent.plugin_loader.docker: using client connection initialized from environment: plugin_dir=/path-without-permission/plugins
2021-10-20T14:38:51.181-0400 [INFO] agent: detected plugin: name=java type=driver plugin_version=0.1.0
2021-10-20T14:38:51.181-0400 [INFO] agent: detected plugin: name=docker type=driver plugin_version=0.1.0
2021-10-20T14:38:51.181-0400 [INFO] agent: detected plugin: name=mock_driver type=driver plugin_version=0.1.0
2021-10-20T14:38:51.181-0400 [INFO] agent: detected plugin: name=raw_exec type=driver plugin_version=0.1.0
2021-10-20T14:38:51.181-0400 [INFO] agent: detected plugin: name=exec type=driver plugin_version=0.1.0
2021-10-20T14:38:51.181-0400 [INFO] agent: detected plugin: name=qemu type=driver plugin_version=0.1.0
2021-10-20T14:38:51.181-0400 [ERROR] agent: error starting agent: error="setting up server node ID failed: mkdir /path-without-permission: read-only file system"
```
This change adds the final `ERROR` message. It's easy to miss the `==>
Error starting agent` above.
Ensure that `""` Scheduler Algorithm gets explicitly set to binpack on
upgrades or on API handling when user misses the value.
The scheduler already treats `""` value as binpack. This PR merely
ensures that the operator API returns the effective value.
Shutdown http server last, after nomad client/server components
terminate.
Before this change, if the agent is taking an unexpectedly long time to
shutdown, the operator cannot query the http server directly: they
cannot access agent specific http endpoints and need to query another
agent about the troublesome agent.
Unexpectedly long shutdown can happen in normal cases, e.g. a client
might hung is if one of the allocs it is running has a long
shutdown_delay.
Here, we switch to ensuring that the http server is shutdown last.
I believe this doesn't require extra care in agent shutting down logic
while operators may be able to submit write http requests. We already
need to cope with operators submiting these http requests to another
agent or by servers updating the client allocations.
allow oss to parse sink duration
clean up audit sink parsing
ent eventer config reload
fix typo
SetEnabled to eventer interface
client acl test
rm dead code
fix failing test
Nomad jobs may be configured with a TaskGroup which contains a Service
definition that is Consul Connect enabled. These service definitions end
up establishing a Consul Connect Proxy Task (e.g. envoy, by default). In
the case where Consul ACLs are enabled, a Service Identity token is required
for these tasks to run & connect, etc. This changeset enables the Nomad Server
to recieve RPC requests for the derivation of SI tokens on behalf of instances
of Consul Connect using Tasks. Those tokens are then relayed back to the
requesting Client, which then injects the tokens in the secrets directory of
the Task.
This change provides an initial pass at setting up the configuration necessary to
enable use of Connect with Consul ACLs. Operators will be able to pass in a Consul
Token through `-consul-token` or `$CONSUL_TOKEN` in the `job run` and `job revert`
commands (similar to Vault tokens).
These values are not actually used yet in this changeset.
This is the basic code to add the Windows Service Manager hooks to Nomad.
Includes vendoring golang.org/x/sys/windows/svc and added Docs:
* guide for installing as a windows service.
* configuration for logging to file from PR #6429
Adds new package that can be used by client and server RPC endpoints to
facilitate monitoring based off of a logger
clean up old code
small comment about write
rm old comment about minsize
rename to Monitor
Removes connection logic from monitor command
Keep connection logic in endpoints, use a channel to send results from
monitoring
use new multisink logger and interfaces
small test for dropped messages
update go-hclogger and update sink/intercept logger interfaces
AgentMonitor is an endpoint to stream logs for a given agent. It allows
callers to pass in a supplied log level, which may be different than the
agents config allowing for temporary debugging with lower log levels.
Pass in logWriter when setting up Agent
Consul Connect must route traffic between network namespaces through a
public interface (i.e. not localhost). In order to support testing in
dev mode, users needed to manually set the interface which doesn't
make for a smooth experience.
This commit adds a facility for adding optional parameters to the
`nomad agent -dev` flag and uses it to add a `-dev=connect` flag that
binds to a public interface on the host.
