ACL policies can be associated with a job so that the job's Workload Identity
can have expanded access to other policy objects, including other
variables. Policies set on the variables the job automatically has access to
were ignored, but this includes policies with `deny` capabilities.
Additionally, when resolving claims for a workload identity without any attached
policies, the `ResolveClaims` method returned a `nil` ACL object, which is
treated similarly to a management token. While this was safe in Nomad 1.4.x,
when the workload identity token was exposed to the task via the `identity`
block, this allows a user with `submit-job` capabilities to escalate their
privileges.
We originally implemented automatic workload access to Variables as a separate
code path in the Variables RPC endpoint so that we don't have to generate
on-the-fly policies that blow up the ACL policy cache. This is fairly brittle
but also the behavior around wildcard paths in policies different from the rest
of our ACL polices, which is hard to reason about.
Add an `ACLClaim` parameter to the `AllowVariableOperation` method so that we
can push all this logic into the `acl` package and the behavior can be
consistent. This will allow a `deny` policy to override automatic access (and
probably speed up checks of non-automatic variable access).
* cli: add -json flag to alloc checks for completion
* CLI: Expand test to include testing the json flag for allocation checks
* Documentation: Add the checks command
* Documentation: Add example for alloc check command
* Update website/content/docs/commands/alloc/checks.mdx
Co-authored-by: James Rasell <jrasell@users.noreply.github.com>
* CLI: Add template flag to alloc checks command
* Update website/content/docs/commands/alloc/checks.mdx
Co-authored-by: James Rasell <jrasell@users.noreply.github.com>
* CLI: Extend test to include -t flag for alloc checks
* func: add changelog for added flags to alloc checks
* cli[doc]: Make usage section on alloc checks clearer
* Update website/content/docs/commands/alloc/checks.mdx
Co-authored-by: James Rasell <jrasell@users.noreply.github.com>
* Delete modd.conf
* cli[doc]: add -t flag to command description for alloc checks
---------
Co-authored-by: James Rasell <jrasell@users.noreply.github.com>
Co-authored-by: Juanita De La Cuesta Morales <juanita.delacuestamorales@juanita.delacuestamorales-LHQ7X0QG9X>
Most job subcommands allow for job ID prefix match as a convenience
functionality so users don't have to type the full job ID.
But this introduces a hard ACL requirement that the token used to run
these commands have the `list-jobs` permission, even if the token has
enough permission to execute the basic command action and the user
passed an exact job ID.
This change softens this requirement by not failing the prefix match in
case the request results in a permission denied error and instead using
the information passed by the user directly.
When the scheduler tries to find a placement for a new allocation, it iterates
over a subset of nodes. For each node, we populate a `NetworkIndex` bitmap with
the ports of all existing allocations and any other allocations already proposed
as part of this same evaluation via its `SetAllocs` method. Then we make an
"ask" of the `NetworkIndex` in `AssignPorts` for any ports we need and receive
an "offer" in return. The offer will include both static ports and any dynamic
port assignments.
The `AssignPorts` method was written to support group networks, and it shares
code that selects dynamic ports with the original `AssignTaskNetwork`
code. `AssignTaskNetwork` can request multiple ports from the bitmap at a
time. But `AssignPorts` requests them one at a time and does not account for
possible collisions, and doesn't return an error in that case.
What happens next varies:
1. If the scheduler doesn't place the allocation on that node, the port
conflict is thrown away and there's no problem.
2. If the node is picked and this is the only allocation (or last allocation),
the plan applier will reject the plan when it calls `SetAllocs`, as we'd expect.
3. If the node is picked and there are additional allocations in the same eval
that iterate over the same node, their call to `SetAllocs` will detect the
impossible state and the node will be rejected. This can have the puzzling
behavior where a second task group for the job without any networking at all
can hit a port collision error!
It looks like this bug has existed since we implemented group networks, but
there are several factors that add up to making the issue rare for many users
yet frustratingly frequent for others:
* You're more likely to hit this bug the more tightly packed your range for
dynamic ports is. With 12000 ports in the range by default, many clusters can
avoid this for a long time.
* You're more likely to hit case (3) for jobs with lots of allocations or if a
scheduler has to iterate over a large number of nodes, such as with system jobs,
jobs with `spread` blocks, or (sometimes) jobs using `unique` constraints.
For unlucky combinations of these factors, it's possible that case (3) happens
repeatedly, preventing scheduling of a given job until a client state
change (ex. restarting the agent so all its allocations are rescheduled
elsewhere) re-opens the range of dynamic ports available.
This changeset:
* Fixes the bug by accounting for collisions in dynamic port selection in
`AssignPorts`.
* Adds test coverage for `AssignPorts`, expands coverage of this case for the
deprecated `AssignTaskNetwork`, and tightens the dynamic port range in a
scheduler test for spread scheduling to more easily detect this kind of problem
in the future.
* Adds a `String()` method to `Bitmap` so that any future "screaming" log lines
have a human-readable list of used ports.
* client: disable running artifact downloader as nobody
This PR reverts a change from Nomad 1.5 where artifact downloads were
executed as the nobody user on Linux systems. This was done as an attempt
to improve the security model of artifact downloading where third party
tools such as git or mercurial would be run as the root user with all
the security implications thereof.
However, doing so conflicts with Nomad's own advice for securing the
Client data directory - which when setup with the recommended directory
permissions structure prevents artifact downloads from working as intended.
Artifact downloads are at least still now executed as a child process of
the Nomad agent, and on modern Linux systems make use of the kernel Landlock
feature for limiting filesystem access of the child process.
* docs: update upgrade guide for 1.5.1 sandboxing
* docs: add cl
* docs: add title to upgrade guide fix
This PR configures
- server nodes with a systemd unit running the agent as the nomad service user
- client nodes with a root owned nomad data directory
* Update ioutil deprecated library references to os and io respectively
* Deal with the errors produced.
Add error handling to filEntry info
Add error handling to info
* Update ioutil library references to os and io respectively for drivers package
No user facing changes so I assume no change log is required
* Fix failing tests
Wildcard datacenters introduced a bug where a job with any wildcard datacenters
will always be treated as a destructive update when we check whether a
datacenter has been removed from the jobspec.
Includes updating the helper so that callers don't have to loop over the job's
datacenters.
* Fix for wildcard DC sys/sysbatch jobs
* A few extra modules for wildcard DC in systemish jobs
* doesMatchPattern moved to its own util as match-glob
* DC glob lookup using matchGlob
* PR feedback
Some of the methods in `Allocations()` incorrectly use the `putQuery`
in API calls where `put` is more appropriate since they are not reading
information back. These methods are also not returning request metadata
such as `LastIndex` back to callers, which can be useful to have in some
scenarios.
They also provide poor developer experience as they take an
`*api.Allocation` struct when only the allocation ID is necessary. This
can lead consumers to make unnecessary API calls to fetch the full
allocation.
Fixing these problems require updating the methods' signatures so they
take `*WriteOptions` instead of `*QueryOptions` and return `*WriteMeta`,
but this is a breaking change that requires advanced notice to consumers.
This commit adds a future breaking change notice and also fixes the
`Stop` method so it properly returns request metadata in a backwards
compatible way.
In Nomad 0.12.1 we introduced atomic job registration/deregistration, where the
new eval was written in the same raft entry. Backwards-compatibility checks were
supposed to have been removed in Nomad 1.1.0, but we missed that. This is long
safe to remove.
Several `nomad job` subcommands had duplicate or slightly similar logic
for resolving a job ID from a CLI argument prefix, while others did not
have this functionality at all.
This commit pulls the shared logic to the command Meta and updates all
`nomad job` subcommands to use it.
When native service discovery was added, we used the node secret as the auth
token. Once Workload Identity was added in Nomad 1.4.x we needed to use the
claim token for `template` blocks, and so we allowed valid claims to bypass the
ACL policy check to preserve the existing behavior. (Invalid claims are still
rejected, so this didn't widen any security boundary.)
In reworking authentication for 1.5.0, we unintentionally removed this
bypass. For WIs without a policy attached to their job, everything works as
expected because the resulting `acl.ACL` is nil. But once a policy is attached
to the job the `acl.ACL` is no longer nil and this causes permissions errors.
Fix the regression by adding back the bypass for valid claims. In future work,
we should strongly consider getting turning the implicit policies into real
`ACLPolicy` objects (even if not stored in state) so that we don't have these
kind of brittle exceptions to the auth code.
The signature of the `raftApply` function requires that the caller unwrap the
first returned value (the response from `FSM.Apply`) to see if it's an
error. This puts the burden on the caller to remember to check two different
places for errors, and we've done so inconsistently.
Update `raftApply` to do the unwrapping for us and return any `FSM.Apply` error
as the error value. Similar work was done in Consul in
https://github.com/hashicorp/consul/pull/9991. This eliminates some boilerplate
and surfaces a few minor bugs in the process:
* job deregistrations of already-GC'd jobs were still emitting evals
* reconcile job summaries does not return scheduler errors
* node updates did not report errors associated with inconsistent service
discovery or CSI plugin states
Note that although _most_ of the `FSM.Apply` functions return only errors (which
makes it tempting to remove the first return value entirely), there are few that
return `bool` for some reason and Variables relies on the response value for
proper CAS checking.
Fixes#16288. An earlier version of `go-plugin` introduced a warning log if
`SecureConfig` is unset. For Nomad and other applications that have "internal"
`go-plugin` consumers where the application runs itself as a plugin, this causes
spurious warn-level logs. For Nomad in particular this means every task driver
and logmon invocation emits the log, which is our primary operation.
The change was reverted upstream, so this changeset picks up the reverted
version.
Nomad servers can advertise independent IP addresses for `serf` and
`rpc`. Somewhat unexpectedly, the `serf` address is also used for both Serf and
server-to-server RPC communication (including Raft RPC). The address advertised
for `rpc` is only used for client-to-server RPC. This split was introduced
intentionally in Nomad 0.8.
When clients are using Consul discovery for connecting to servers, they get an
initial discovery set from Consul and use the correct `rpc` tag in Consul to get
a list of adddresses for servers. The client then makes a `Status.Peers` RPC to
get the list of those servers that are raft peers. But this endpoint is shared
between servers and clients, and provides the address used for Raft.
Most of the time this is harmless because servers will bind on 0.0.0.0 anyways.,
But in topologies where servers are on a private network and clients are on
separate subnets (or even public subnets), clients will make initial contact
with the server to get the list of peers but then populate their local server
set with unreachable addresses.
Cluster administrators can work around this problem by using `server_join` with
specific IP addresses (or DNS names), because the `Node.UpdateStatus` endpoint
returns the correct set of RPC addresses when updating the node. So once a
client has registered, it will get the correct set of RPC addresses.
This changeset updates the client logic to query `Status.Members` instead of
`Status.Peers`, and then extract the correctly advertised address and port from
the response body.
hc-github-team-nomad-core