* users: create cache for user lookups
This PR introduces a global cache for OS user lookups. This should
relieve pressure on the OS domain/directory lookups, which would be
queried more now that Task API exists.
Hits are cached for 1 hour, and misses are cached for 1 minute. These
values are fairly arbitrary - we can tweak them if there is any reason to.
Closes#16010
* users: delete expired negative entry from cache
This change introduces the Task API: a portable way for tasks to access Nomad's HTTP API. This particular implementation uses a Unix Domain Socket and, unlike the agent's HTTP API, always requires authentication even if ACLs are disabled.
This PR contains the core feature and tests but followup work is required for the following TODO items:
- Docs - might do in a followup since dynamic node metadata / task api / workload id all need to interlink
- Unit tests for auth middleware
- Caching for auth middleware
- Rate limiting on negative lookups for auth middleware
---------
Co-authored-by: Seth Hoenig <shoenig@duck.com>
Add `identity` jobspec block to expose workload identity tokens to tasks.
---------
Co-authored-by: Anders <mail@anars.dk>
Co-authored-by: Tim Gross <tgross@hashicorp.com>
Co-authored-by: Michael Schurter <mschurter@hashicorp.com>
* vault: configure user agent on Nomad vault clients
This PR attempts to set the User-Agent header on each Vault API client
created by Nomad. Still need to figure a way to set User-Agent on the
Vault client created internally by consul-template.
* vault: fixup find-and-replace gone awry
API and RPC endpoints for ACLAuthMethods and ACLBindingRules should allow users
to send incomplete objects in order to, e.g., update single fields. This PR
provides "merging" functionality for these endpoints.
This change adds a new table that will store ACL binding rule
objects. The two indexes allow fast lookups by their ID, or by
which auth method they are linked to. Snapshot persist and
restore functionality ensures this table can be saved and
restored from snapshots.
In order to write and delete the object to state, new Raft messages
have been added.
All RPC request and response structs, along with object functions
such as diff and canonicalize have been included within this work
as it is nicely separated from the other areas of work.
This PR adds Merge() helper function for choosing which value of two pointers
to use during a larger merge operation.
If 'next' is not nil, use that value, otherwise use the 'previous' value.
* client: sandbox go-getter subprocess with landlock
This PR re-implements the getter package for artifact downloads as a subprocess.
Key changes include
On all platforms, run getter as a child process of the Nomad agent.
On Linux platforms running as root, run the child process as the nobody user.
On supporting Linux kernels, uses landlock for filesystem isolation (via go-landlock).
On all platforms, restrict environment variables of the child process to a static set.
notably TMP/TEMP now points within the allocation's task directory
kernel.landlock attribute is fingerprinted (version number or unavailable)
These changes make Nomad client more resilient against a faulty go-getter implementation that may panic, and more secure against bad actors attempting to use artifact downloads as a privilege escalation vector.
Adds new e2e/artifact suite for ensuring artifact downloading works.
TODO: Windows git test (need to modify the image, etc... followup PR)
* landlock: fixup items from cr
* cr: fixup tests and go.mod file
Upcoming work to instrument the rate of RPC requests by consumer (and eventually
rate limit) require that we authenticate a RPC request before forwarding. Add a
new top-level `Authenticate` method to the server and have it return an
`AuthenticatedIdentity` struct. RPC handlers will use the relevant fields of
this identity for performing authorization.
This changeset includes:
* The main implementation of `Authenticate`
* Provide a new RPC `ACL.WhoAmI` for debugging authentication. This endpoint
returns the same `AuthenticatedIdentity` that will be used by RPC handlers. At
some point we might want to give this an equivalent HTTP endpoint but I didn't
want to add that to our public API until some of the other Workload Identity
work is solidified, especially if we don't need it yet.
* A full coverage test of the `Authenticate` method. This sets up two server
nodes with mTLS and ACLs, some tokens, and some allocations with workload
identities.
* Wire up an example of using `Authenticate` in the `Namespace.Upsert` RPC and
see how authorization happens after forwarding.
* A new semgrep rule for `Authenticate`, which we'll need to update once we're
ready to wire up more RPC endpoints with authorization steps.
* client: avoid unconsumed channel in timer construction
This PR fixes a bug introduced in #11983 where a Timer initialized with 0
duration causes an immediate tick, even if Reset is called before reading the
channel. The fix is to avoid doing that, instead creating a Timer with a non-zero
initial wait time, and then immediately calling Stop.
* pr: remove redundant stop
This PR implements ACLAuthMethod type, acl_auth_methods table schema and crud state store methods. It also updates nomadSnapshot.Persist and nomadSnapshot.Restore methods in order for them to work with the new table, and adds two new Raft messages: ACLAuthMethodsUpsertRequestType and ACLAuthMethodsDeleteRequestType
This PR is part of the SSO work captured under ☂️ ticket #13120.
* helpers: lockfree lookup of nobody user on linux and darwin
This PR continues the nobody user lookup saga, by making the nobody
user lookup lock-free on linux and darwin.
By doing the lookup in an init block this originally broke on Windows,
where we must avoid doing the lookup at all. We can get around that
breakage by only doing the lookup on linux/darwin where the nobody
user is going to exist.
Also return the nobody user by value so that a copy is created that
cannot be modified by callers of Nobody().
* helper: move nobody code into unix file
In #14742 we introduced a cached lookup of the `nobody` user, which is only ever
called on Unixish machines. But the initial caching was being done in an `init`
block, which meant it was being run on Windows as well. This prevents the Nomad
agent from starting on Windows.
An alternative fix here would be to have a separate `init` block for Windows and
Unix, but this potentially masks incorrect behavior if we accidentally added a
call to the `Nobody()` method on Windows later. This way we're forced to handle
the error in the caller.
* client: protect user lookups with global lock
This PR updates Nomad client to always do user lookups while holding
a global process lock. This is to prevent concurrency unsafe implementations
of NSS, but still enabling NSS lookups of users (i.e. cannot not use osusergo).
* cl: add cl
* cleanup: refactor MapStringStringSliceValueSet to be cleaner
* cleanup: replace SliceStringToSet with actual set
* cleanup: replace SliceStringSubset with real set
* cleanup: replace SliceStringContains with slices.Contains
* cleanup: remove unused function SliceStringHasPrefix
* cleanup: fixup StringHasPrefixInSlice doc string
* cleanup: refactor SliceSetDisjoint to use real set
* cleanup: replace CompareSliceSetString with SliceSetEq
* cleanup: replace CompareMapStringString with maps.Equal
* cleanup: replace CopyMapStringString with CopyMap
* cleanup: replace CopyMapStringInterface with CopyMap
* cleanup: fixup more CopyMapStringString and CopyMapStringInt
* cleanup: replace CopySliceString with slices.Clone
* cleanup: remove unused CopySliceInt
* cleanup: refactor CopyMapStringSliceString to be generic as CopyMapOfSlice
* cleanup: replace CopyMap with maps.Clone
* cleanup: run go mod tidy
This PR modifies RandomStagger to protect against negative input
values. If the given interval is negative, the value returned will
be somewhere in the stratosphere. Instead, treat negative inputs
like zero, returning zero.
Update the on-disk format for the root key so that it's wrapped with a unique
per-key/per-server key encryption key. This is a bit of security theatre for the
current implementation, but it uses `go-kms-wrapping` as the interface for
wrapping the key. This provides a shim for future support of external KMS such
as cloud provider APIs or Vault transit encryption.
* Removes the JSON serialization extension we had on the `RootKey` struct; this
struct is now only used for key replication and not for disk serialization, so
we don't need this helper.
* Creates a helper for generating cryptographically random slices of bytes that
properly accounts for short reads from the source.
* No observable functional changes outside of the on-disk format, so there are
no test updates.
This PR creates a pointer.Compare helper for comparing equality of
two pointers. Strictly only works with primitive types we know are
safe to derefence and compare using '=='.
Before this change, Client had 2 copies of the config object: config and configCopy. There was no guidance around which to use where (other than configCopy's comment to pass it to alloc runners), both are shared among goroutines and mutated in data racy ways. At least at one point I think the idea was to have `config` be mutable and then grab a lock to overwrite `configCopy`'s pointer atomically. This would have allowed alloc runners to read their config copies in data race safe ways, but this isn't how the current implementation worked.
This change takes the following approach to safely handling configs in the client:
1. `Client.config` is the only copy of the config and all access must go through the `Client.configLock` mutex
2. Since the mutex *only protects the config pointer itself and not fields inside the Config struct:* all config mutation must be done on a *copy* of the config, and then Client's config pointer is overwritten while the mutex is acquired. Alloc runners and other goroutines with the old config pointer will not see config updates.
3. Deep copying is implemented on the Config struct to satisfy the previous approach. The TLS Keyloader is an exception because it has its own internal locking to support mutating in place. An unfortunate complication but one I couldn't find a way to untangle in a timely fashion.
4. To facilitate deep copying I made an *internally backward incompatible API change:* our `helper/funcs` used to turn containers (slices and maps) with 0 elements into nils. This probably saves a few memory allocations but makes it very easy to cause panics. Since my new config handling approach uses more copying, it became very difficult to ensure all code that used containers on configs could handle nils properly. Since this code has caused panics in the past, I fixed it: nil containers are copied as nil, but 0-element containers properly return a new 0-element container. No more "downgrading to nil!"
Move conflict resolution implementation into the state store with a new Apply RPC.
This also makes the RPC for secure variables much more similar to Consul's KV,
which will help us support soft deletes in a post-1.4.0 version of Nomad.
Reimplement quotas in the state store functions.
Co-authored-by: Charlie Voiselle <464492+angrycub@users.noreply.github.com>
This commit includes the new state schema for ACL roles along with
state interaction functions for CRUD actions.
The change also includes snapshot persist and restore
functionality and the addition of FSM messages for Raft updates
which will come via RPC endpoints.
The ACL token state schema has been updated to utilise two new
indexes which track expiration of tokens that are configured with
an expiration TTL or time. A new state function allows listing
ACL expired tokens which will be used by internal garbage
collection.
The ACL endpoint has been modified so that all validation happens
within a single function call. This is easier to understand and
see at a glance. The ACL token validation now also includes logic
for expiry TTL and times. The ACL endpoint upsert tests have been
condensed into a single, table driven test.
There is a new token canonicalize which provides a single place
for token canonicalization, rather than logic spread in the RPC
handler.
This PR adds support for specifying checks in services registered to
the built-in nomad service provider.
Currently only HTTP and TCP checks are supported, though more types
could be added later.
Stream snapshot to FSM when restoring from archive
The `RestoreFromArchive` helper decompresses the snapshot archive to a
temporary file before reading it into the FSM. For large snapshots
this performs a lot of disk IO. Stream decompress the snapshot as we
read it, without first writing to a temporary file.
Add bexpr filters to the `RestoreFromArchive` helper.
The operator can pass these as `-filter` arguments to `nomad operator
snapshot state` (and other commands in the future) to include only
desired data when reading the snapshot.
Seth Hoenig