We use capped exponential backoff in several places in the code when handling
failures. The code we've copy-and-pasted all over has a check to see if the
backoff is greater than the limit, but this check happens after the bitshift and
we always increment the number of attempts. This causes an overflow with a
fairly small number of failures (ex. at one place I tested it occurs after only
24 iterations), resulting in a negative backoff which then never recovers. The
backoff becomes a tight loop consuming resources and/or DoS'ing a Nomad RPC
handler or an external API such as Vault. Note this doesn't occur in places
where we cap the number of iterations so the loop breaks (usually to return an
error), so long as the number of iterations is reasonable.
Introduce a helper with a check on the cap before the bitshift to avoid overflow in all
places this can occur.
Fixes: #18199
Co-authored-by: stswidwinski <stan.swidwinski@gmail.com>
* build: update to go1.21
* go: eliminate helpers in favor of min/max
* build: run go mod tidy
* build: swap depguard for semgrep
* command: fixup broken tls error check on go1.21
When claiming a CSI volume, we need to ensure the CSI node plugin is running
before we send any CSI RPCs. This extends even to the controller publish RPC
because it requires the storage provider's "external node ID" for the
client. This primarily impacts client restarts but also is a problem if the node
plugin exits (and fingerprints) while the allocation that needs a CSI volume
claim is being placed.
Unfortunately there's no mapping of volume to plugin ID available in the
jobspec, so we don't have enough information to wait on plugins until we either
get the volume from the server or retrieve the plugin ID from data we've
persisted on the client.
If we always require getting the volume from the server before making the claim,
a client restart for disconnected clients will cause all the allocations that
need CSI volumes to fail. Even while connected, checking in with the server to
verify the volume's plugin before trying to make a claim RPC is inherently racy,
so we'll leave that case as-is and it will fail the claim if the node plugin
needed to support a newly-placed allocation is flapping such that the node
fingerprint is changing.
This changeset persists a minimum subset of data about the volume and its plugin
in the client state DB, and retrieves that data during the CSI hook's prerun to
avoid re-claiming and remounting the volume unnecessarily.
This changeset also updates the RPC handler to use the external node ID from the
claim whenever it is available.
Fixes: #13028
The `nomad tls cert` command did not create certificates with the correct SANs for
them to work with non default domain and region names. This changset updates the
code to support non default domains and regions in the certificates.
Implementation of the base work for the new node pools feature. It includes a new `NodePool` struct and its corresponding state store table.
Upon start the state store is populated with two built-in node pools that cannot be modified nor deleted:
* `all` is a node pool that always includes all nodes in the cluster.
* `default` is the node pool where nodes that don't specify a node pool in their configuration are placed.
This PR does some cleanup of an old code path for versions of Consul that
did not support reporting the supported versions of Envoy in its API. Those
versions are no longer supported for years at this point, and the fallback
version of envoy hasn't been supported by any version of Consul for almost
as long. Remove this code path that is no longer useful.
This PR modifies references to the envoyproxy/envoy docker image to
explicitly include the docker.io prefix. This does not affect existing
users, but makes things easier for Podman users, who otherwise need to
specify the full name because Podman does not default to docker.io
* Upgrade from hashicorp/go-msgpack v1.1.5 to v2.1.0
Fixes#16808
* Update hashicorp/net-rpc-msgpackrpc to v2 to match go-msgpack
* deps: use go-msgpack v2.0.0
go-msgpack v2.1.0 includes some code changes that we will need to
investigate furthere to assess its impact on Nomad, so keeping this
dependency on v2.0.0 for now since it's no-op.
---------
Co-authored-by: Luiz Aoqui <luiz@hashicorp.com>
This PR eliminates code specific to looking up and caching the uid/gid/user.User
object associated with the nobody user in an init block. This code existed before
adding the generic users cache and was meant to optimize the one search path we
knew would happen often. Now that we have the cache, seems reasonable to eliminate
this init block and use the cache instead like for any other user.
Also fixes a constraint on the podman (and other) drivers, where building without
CGO became problematic on some OS like Fedora IoT where the nobody user cannot
be found with the pure-Go standard library.
Fixes github.com/hashicorp/nomad-driver-podman/issues/228
* client/fingerprint: correctly fingerprint E/P cores of Apple Silicon chips
This PR adds detection of asymetric core types (Power & Efficiency) (P/E)
when running on M1/M2 Apple Silicon CPUs. This functionality is provided
by shoenig/go-m1cpu which makes use of the Apple IOKit framework to read
undocumented registers containing CPU performance data. Currently working
on getting that functionality merged upstream into gopsutil, but gopsutil
would still not support detecting P vs E cores like this PR does.
Also refactors the CPUFingerprinter code to handle the mixed core
types, now setting power vs efficiency cpu attributes.
For now the scheduler is still unaware of mixed core types - on Apple
platforms tasks cannot reserve cores anyway so it doesn't matter, but
at least now the total CPU shares available will be correct.
Future work should include adding support for detecting P/E cores on
the latest and upcoming Intel chips, where computation of total cpu shares
is currently incorrect. For that, we should also include updating the
scheduler to be core-type aware, so that tasks of resources.cores on Linux
platforms can be assigned the correct number of CPU shares for the core
type(s) they have been assigned.
node attributes before
cpu.arch = arm64
cpu.modelname = Apple M2 Pro
cpu.numcores = 12
cpu.reservablecores = 0
cpu.totalcompute = 1000
node attributes after
cpu.arch = arm64
cpu.frequency.efficiency = 2424
cpu.frequency.power = 3504
cpu.modelname = Apple M2 Pro
cpu.numcores.efficiency = 4
cpu.numcores.power = 8
cpu.reservablecores = 0
cpu.totalcompute = 37728
* fingerprint/cpu: follow up cr items
* Warn when Items key isn't directly accessible
Go template requires that map keys are alphanumeric for direct access
using the dotted reference syntax. This warns users when they create
keys that run afoul of this requirement.
- cli: use regex to detect invalid indentifiers in var keys
- test: fix slash in escape test case
- api: share warning formatting function between API and CLI
- ui: warn if var key has characters other than _, letter, or number
---------
Co-authored-by: Charlie Voiselle <464492+angrycub@users.noreply.github.com>
Co-authored-by: Luiz Aoqui <luiz@hashicorp.com>
* 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.
