Files
seaweedfs/weed/server/filer_server.go
T
Chris Lu 38c14d3c13 filer: apply SSRF guard to the lazy-remote fetch/list/delete paths (#11294)
* filer: add guarded remote-storage client builder hook for lazy fetch

The lazy-remote fetch path (maybeLazyFetchFromRemote) resolved its
remote-storage client through the unguarded shared cache, bypassing the
SSRF chokepoint (BuildGuardedRemoteStorageClient) that the CVE-2026-73080
remediation wired into the volume, filer stream and s3 stream dial paths.

Add a RemoteStorageClientBuilder hook on Filer plus conf-only lookups on
FilerRemoteStorage, and route the lazy fetch through the builder when set
(endpoint deny-list + DNS-rebinding-safe dialer), falling back to the
shared cache otherwise. The filer server wires the builder in a follow-up.

* filer: route lazy directory listing through the guarded remote client

maybeLazyListFromRemote shared the unguarded client resolution of the
fetch path, so a caller-supplied remote endpoint was dialed without the
SSRF deny-list or rebinding-safe dialer. Resolve the conf and build the
client through buildRemoteStorageClient so the same guard covers listing.

* filer: route lazy remote delete through the guarded remote client

maybeDeleteFromRemote issued outbound DELETE/RemoveDirectory requests
through the unguarded client, giving a write-side SSRF to a caller-chosen
endpoint. Resolve the conf and build the client through
buildRemoteStorageClient so the endpoint deny-list and rebinding-safe
dialer apply to the delete path as well.

* filer server: wire the guarded remote client builder into the filer

Set Filer.BuildGuardedRemoteClient to BuildGuardedRemoteStorageClient and
forward AllowUntrustedRemoteEndpoints so the lazy-remote fetch, list and
delete paths apply the same SSRF endpoint checks as the volume and
streaming read paths.

* filer: test lazy fetch honors the guarded remote client builder

Add a regression test that sets BuildGuardedRemoteClient to a rejecting
builder and asserts maybeLazyFetchFromRemote returns no entry without
reaching the remote, covering the SSRF guard wired in the prior commits.

* filer: skip remote client for local-only lazy deletes

maybeDeleteFromRemote resolved and validated the mount's remote client
before checking entry.Remote, so a local-only file (no Remote entry) under
a mount whose endpoint the guard rejects failed to delete: the guard
error aborted the metadata deletion, leaving a file that needs no remote
operation undeletable. Move the local-only check ahead of client
construction so only remote-backed files and directories pay the guard.

* filer: build the guarded remote client inside the lazy singleflight

The lazy fetch and list paths built the guarded client before their
singleflight blocks, so concurrent requests for the same key each
allocated a fresh SDK client and HTTP transport even though only one
remote operation ran. Move client construction inside the singleflight
so the deduplicated operation builds it once, matching the per-request
guard semantics of the sibling streaming paths without the duplicate
transport churn.

* filer: test guarded rejection for the lazy list and delete paths

Add regression tests that set BuildGuardedRemoteClient to a rejecting
builder and assert the lazy list does not reach the remote, a
remote-backed file delete is blocked, and a local-only file under a
rejected mount still deletes (covering the local-only fix).

* filer: decouple lazy guarded-client build from the first caller's context

Building the guarded client inside the singleflight made concurrent
fetches share the first caller's context. If that caller canceled while
endpoint DNS validation was running, the builder returned an error and
published a not-found result to other callers whose contexts were still
valid. Build with context.WithoutCancel so the guard's DNS validation
is not tied to any single caller's cancellation, matching the list
path's existing decoupling for the remote operation itself.

* filer: reject remote-storage confs that dial blocked endpoints at load

The filer's lazy-fetch / lazy-list / remote-delete paths resolve remote
storage clients by name from FilerRemoteStorage.storageNameToConf and
dial them via remote_storage.GetRemoteStorage, which bypasses the SSRF
deny-list the volume server (BuildGuardedRemoteStorageClient) and the
filer's own direct-read path apply. A RemoteConf planted under
/etc/remote with a loopback / private / IMDS S3 endpoint is reloaded into
storageNameToConf on the next metadata-change event and then dialed on
the next cache miss — server-side request forgery from the filer.

Apply the volume server's SSRF deny-list at conf load time, the single
chokepoint that populates storageNameToConf:

- Add RemoteStorageConfValidator, injected into FilerRemoteStorage by
  the filer server (the filer package cannot import the server package).
  A conf that fails validation is dropped from storageNameToConf, so the
  name-based client resolution on the lazy paths returns "not found"
  instead of dialing the blocked endpoint.
- Add ValidateRemoteConfForLoad in weed_server, which mirrors
  BuildGuardedRemoteStorageClient's gcs credential + endpoint checks
  (validateRemoteEndpoint via guardedRemoteClient) without building a
  client. allowUntrusted skips the check, mirroring the volume server
  opt-out (-filer.allowUntrustedRemoteEndpoints).
- The filer server injects the validator at construction.

A conf whose type dials a fixed provider host (no caller-supplied
endpoint) passes; only caller-influenced endpoints are denied.

* filer: skip DNS resolution in the load-time SSRF validator

ValidateRemoteConfForLoad resolved hostnames during /etc/remote reload,
so a transient DNS failure (2s timeout) dropped the conf from the fresh
map that replaces the live map, disabling a working mount until the next
metadata event. The build-time guard (BuildGuardedRemoteStorageClient)
already re-resolves and re-validates the endpoint at dial time with the
rebinding-safe dialer, so DNS at load is redundant for security.

Split the static checks (scheme, IMDS hostnames, IP-literal blocked
addresses, gcs credentials) into validateRemoteEndpointForLoad, which
does no DNS. Hostname endpoints pass at load and are caught at dial if
they resolve to a blocked address. This preserves fail-fast for
statically-blocked confs (loopback IPs, IMDS hostnames) without letting
transient DNS failures disable mounts.

* filer: accept empty S3 endpoints in the guarded remote client builder

guardedRemoteClient returned ok=true with an empty endpoint for a
standard AWS S3 config (no custom S3Endpoint), so
BuildGuardedRemoteStorageClient and ValidateRemoteConfForLoad rejected
it with "remote endpoint is empty" — breaking standard AWS S3 mounts on
the lazy paths and the sibling streaming read paths that already use the
guarded builder.

An empty endpoint is not caller-supplied: the AWS SDK derives the
regional endpoint from the region, so there is nothing for the SSRF
guard to validate. Return ok=false for empty S3-compatible endpoints so
the builder falls through to the shared unguarded cache, matching the
historical behavior for standard AWS S3.
2026-09-13 14:43:55 -07:00

381 lines
15 KiB
Go

package weed_server
import (
"context"
"fmt"
"net/http"
"os"
"strings"
"sync"
"sync/atomic"
"time"
"github.com/seaweedfs/seaweedfs/weed/credential"
"github.com/seaweedfs/seaweedfs/weed/stats"
"golang.org/x/sync/singleflight"
"google.golang.org/grpc"
"github.com/seaweedfs/seaweedfs/weed/util/grace"
"github.com/seaweedfs/seaweedfs/weed/operation"
"github.com/seaweedfs/seaweedfs/weed/pb"
"github.com/seaweedfs/seaweedfs/weed/pb/filer_pb"
"github.com/seaweedfs/seaweedfs/weed/pb/master_pb"
"github.com/seaweedfs/seaweedfs/weed/pb/remote_pb"
"github.com/seaweedfs/seaweedfs/weed/util"
util_http "github.com/seaweedfs/seaweedfs/weed/util/http"
"github.com/seaweedfs/seaweedfs/weed/filer"
_ "github.com/seaweedfs/seaweedfs/weed/filer/arangodb"
_ "github.com/seaweedfs/seaweedfs/weed/filer/cassandra"
_ "github.com/seaweedfs/seaweedfs/weed/filer/cassandra2"
_ "github.com/seaweedfs/seaweedfs/weed/filer/elastic/v7"
_ "github.com/seaweedfs/seaweedfs/weed/filer/etcd"
_ "github.com/seaweedfs/seaweedfs/weed/filer/foundationdb"
_ "github.com/seaweedfs/seaweedfs/weed/filer/hbase"
_ "github.com/seaweedfs/seaweedfs/weed/filer/leveldb"
_ "github.com/seaweedfs/seaweedfs/weed/filer/leveldb2"
_ "github.com/seaweedfs/seaweedfs/weed/filer/leveldb3"
_ "github.com/seaweedfs/seaweedfs/weed/filer/mongodb"
_ "github.com/seaweedfs/seaweedfs/weed/filer/mysql"
_ "github.com/seaweedfs/seaweedfs/weed/filer/mysql2"
"github.com/seaweedfs/seaweedfs/weed/filer/posixlock"
_ "github.com/seaweedfs/seaweedfs/weed/filer/postgres"
_ "github.com/seaweedfs/seaweedfs/weed/filer/postgres2"
_ "github.com/seaweedfs/seaweedfs/weed/filer/redis"
_ "github.com/seaweedfs/seaweedfs/weed/filer/redis2"
_ "github.com/seaweedfs/seaweedfs/weed/filer/redis3"
_ "github.com/seaweedfs/seaweedfs/weed/filer/sqlite"
_ "github.com/seaweedfs/seaweedfs/weed/filer/tarantool"
_ "github.com/seaweedfs/seaweedfs/weed/filer/ydb"
"github.com/seaweedfs/seaweedfs/weed/glog"
"github.com/seaweedfs/seaweedfs/weed/notification"
_ "github.com/seaweedfs/seaweedfs/weed/notification/aws_sqs"
_ "github.com/seaweedfs/seaweedfs/weed/notification/gocdk_pub_sub"
_ "github.com/seaweedfs/seaweedfs/weed/notification/google_pub_sub"
_ "github.com/seaweedfs/seaweedfs/weed/notification/kafka"
_ "github.com/seaweedfs/seaweedfs/weed/notification/log"
_ "github.com/seaweedfs/seaweedfs/weed/notification/webhook"
"github.com/seaweedfs/seaweedfs/weed/security"
)
type FilerOption struct {
Masters *pb.ServerDiscovery
FilerGroup string
Collection string
DefaultReplication string
DisableDirListing bool
MaxMB int
DirListingLimit int
DataCenter string
Rack string
DataNode string
DefaultLevelDbDir string
DisableHttp bool
Host pb.ServerAddress
recursiveDelete bool
Cipher bool
SaveToFilerLimit int64
ConcurrentUploadLimit int64
ConcurrentFileUploadLimit int64
ShowUIDirectoryDelete bool
DownloadMaxBytesPs int64
DiskType string
AllowedOrigins []string
ExposeDirectoryData bool
TusBasePath string
TusMaxSize int64
TusSessionExpiry time.Duration
S3ConfigFile string // optional path to static S3 identity config file
CredentialManager *credential.CredentialManager
// AllowUntrustedRemoteEndpoints lets a read of a remote-only entry dial a
// mounted endpoint that resolves to a loopback / private / metadata host.
AllowUntrustedRemoteEndpoints bool
}
type FilerServer struct {
inFlightDataSize int64
inFlightUploads int64
inFlightDataLimitCond *sync.Cond
filer_pb.UnimplementedSeaweedFilerServer
option *FilerOption
filer *filer.Filer
filerGuard *security.Guard
volumeGuard *security.Guard
grpcDialOption grpc.DialOption
// metrics read from the master
metricsAddress string
metricsIntervalSec int
// track known metadata listeners
knownListenersLock sync.Mutex
knownListeners map[int32]int32
// live metadata subscribers (FUSE mounts, S3, peer filers, ...) keyed by
// clientId, guarded by knownListenersLock. Exposed via ListMetadataSubscribers.
subscribers map[int32]*metadataSubscriber
// deduplicates concurrent remote object caching operations
remoteCacheGroup singleflight.Group
recentCopyRequestsMu sync.Mutex
recentCopyRequests map[string]recentCopyRequest
// credential manager for IAM operations
CredentialManager *credential.CredentialManager
// mountPeerRegistry backs the MountRegister / MountList RPCs for peer
// chunk sharing (tier 1). Always populated.
mountPeerRegistry *filer.MountPeerRegistry
// tusActiveUploads marks TUS sessions with a mutating request in flight, so
// a concurrent PATCH or DELETE is refused instead of recording duplicate
// chunks behind the first request's back.
tusActiveUploads sync.Map
// entryLockTable serializes mutations to the same entry path on this filer.
// CreateEntry takes it today; UpdateEntry and DeleteEntry are intended to take
// it too as their callers route a key's writes to this node, making it the
// local serialization point for read-modify-write operations that replaces
// the distributed lock for that key. Idle keys are evicted automatically, so
// the table stays bounded.
entryLockTable *util.LockTable[util.FullPath]
// posixLocks is the in-memory authority for cross-mount POSIX advisory locks
// on inodes this filer owns (per the route-by-key ring). Lock state is kept
// here rather than in replicated metadata: it is transient coordination, so
// keeping it off the meta-log avoids churn.
posixLocks *posixlock.Manager
// posixLockSweeperStop stops the lease-reaping sweeper goroutine on Shutdown.
posixLockSweeperStop chan struct{}
// posixLockReadyAt is the unix-nanos when this filer began serving POSIX
// locks. For posixLockWarmup after it, the owner defers would-be grants while
// mounts re-assert, so a (re)started owner does not double-grant from empty
// state. Atomic so the handler reads it without locking; 0 means "not warming
// up" (e.g. in tests).
posixLockReadyAt atomic.Int64
}
func NewFilerServer(defaultMux, readonlyMux *http.ServeMux, option *FilerOption) (fs *FilerServer, err error) {
v := util.GetViper()
signingKey := v.GetString("jwt.filer_signing.key")
v.SetDefault("jwt.filer_signing.expires_after_seconds", 10)
expiresAfterSec := v.GetInt("jwt.filer_signing.expires_after_seconds")
readSigningKey := v.GetString("jwt.filer_signing.read.key")
v.SetDefault("jwt.filer_signing.read.expires_after_seconds", 60)
readExpiresAfterSec := v.GetInt("jwt.filer_signing.read.expires_after_seconds")
volumeSigningKey := v.GetString("jwt.signing.key")
v.SetDefault("jwt.signing.expires_after_seconds", 10)
volumeExpiresAfterSec := v.GetInt("jwt.signing.expires_after_seconds")
volumeReadSigningKey := v.GetString("jwt.signing.read.key")
v.SetDefault("jwt.signing.read.expires_after_seconds", 60)
volumeReadExpiresAfterSec := v.GetInt("jwt.signing.read.expires_after_seconds")
v.SetDefault("cors.allowed_origins.values", "*")
allowedOrigins := v.GetString("cors.allowed_origins.values")
domains := strings.Split(allowedOrigins, ",")
option.AllowedOrigins = domains
// -exposeDirectoryData and filer.expose_directory_metadata both default to
// on, and either one turning it off has to hold: this is what keeps the
// directory listing off a filer whose reads are otherwise unauthenticated.
v.SetDefault("filer.expose_directory_metadata.enabled", true)
option.ExposeDirectoryData = option.ExposeDirectoryData && v.GetBool("filer.expose_directory_metadata.enabled")
fs = &FilerServer{
option: option,
grpcDialOption: security.LoadClientTLS(util.GetViper(), "grpc.filer"),
knownListeners: make(map[int32]int32),
subscribers: make(map[int32]*metadataSubscriber),
inFlightDataLimitCond: sync.NewCond(new(sync.Mutex)),
recentCopyRequests: make(map[string]recentCopyRequest),
CredentialManager: option.CredentialManager,
entryLockTable: util.NewLockTable[util.FullPath](),
posixLocks: posixlock.NewManager(),
}
fs.startPosixLockSweeper()
fs.mountPeerRegistry = filer.NewMountPeerRegistry()
go fs.runMountPeerRegistrySweeper()
option.Masters.RefreshBySrvIfAvailable()
if len(option.Masters.GetInstances()) == 0 {
glog.Fatal("master list is required!")
}
if !util.LoadConfiguration("filer", false) {
v.SetDefault("leveldb2.enabled", true)
v.SetDefault("leveldb2.dir", option.DefaultLevelDbDir)
_, err := os.Stat(option.DefaultLevelDbDir)
if os.IsNotExist(err) {
os.MkdirAll(option.DefaultLevelDbDir, 0755)
}
glog.V(0).Infof("default to create filer store dir in %s", option.DefaultLevelDbDir)
} else {
glog.Warningf("skipping default store dir in %s", option.DefaultLevelDbDir)
}
util.LoadConfiguration("notification", false)
v.SetDefault("filer.options.max_file_name_length", 255)
maxFilenameLength := v.GetUint32("filer.options.max_file_name_length")
glog.V(0).Infof("max_file_name_length %d", maxFilenameLength)
fs.filer = filer.NewFiler(*option.Masters, fs.grpcDialOption, option.Host, option.FilerGroup, option.Collection, option.DefaultReplication, option.DataCenter, maxFilenameLength, nil)
fs.filer.Cipher = option.Cipher
fs.filer.DefaultDiskType = option.DiskType
fs.filer.BuildGuardedRemoteClient = BuildGuardedRemoteStorageClient
fs.filer.AllowUntrustedRemoteEndpoints = option.AllowUntrustedRemoteEndpoints
fs.filer.RemoteStorage.SetConfValidator(func(ctx context.Context, conf *remote_pb.RemoteConf) error {
return ValidateRemoteConfForLoad(ctx, conf, option.AllowUntrustedRemoteEndpoints)
})
// we do not support IP whitelist right now https://github.com/seaweedfs/seaweedfs/issues/7094
if v.GetString("guard.white_list") != "" {
glog.Warningf("filer: guard.white_list is configured but the IP whitelist feature is currently disabled. See https://github.com/seaweedfs/seaweedfs/issues/7094")
}
fs.filerGuard = security.NewGuard([]string{}, signingKey, expiresAfterSec, readSigningKey, readExpiresAfterSec)
fs.volumeGuard = security.NewGuard([]string{}, volumeSigningKey, volumeExpiresAfterSec, volumeReadSigningKey, volumeReadExpiresAfterSec)
fs.checkWithMaster()
go stats.LoopPushingMetric("filer", string(fs.option.Host), fs.metricsAddress, fs.metricsIntervalSec)
go fs.filer.MasterClient.KeepConnectedToMaster(context.Background())
fs.option.recursiveDelete = v.GetBool("filer.options.recursive_delete")
v.SetDefault("filer.options.buckets_folder", "/buckets")
fs.filer.DirBucketsPath = v.GetString("filer.options.buckets_folder")
// TODO deprecated, will be removed after 2020-12-31
// replaced by https://github.com/seaweedfs/seaweedfs/wiki/Path-Specific-Configuration
// fs.filer.FsyncBuckets = v.GetStringSlice("filer.options.buckets_fsync")
isFresh := fs.filer.LoadConfiguration(v)
notification.LoadConfiguration(v, "notification.")
handleStaticResources(defaultMux)
if !option.DisableHttp {
defaultMux.HandleFunc("/healthz", requestIDMiddleware(fs.filerHealthzHandler))
defaultMux.HandleFunc("/readyz", requestIDMiddleware(fs.filerHealthzHandler))
// TUS resumable upload protocol handler
if option.TusBasePath != "" {
// Normalize TusPath to always have a leading slash and no trailing slash
if !strings.HasPrefix(option.TusBasePath, "/") {
option.TusBasePath = "/" + option.TusBasePath
}
option.TusBasePath = strings.TrimRight(option.TusBasePath, "/")
// Disallow using "/" as TUS base to avoid hijacking all filer routes
if option.TusBasePath == "" {
glog.Warningf("Invalid TUS base path; TUS disabled (must not be root '/')")
} else {
if option.TusMaxSize <= 0 {
option.TusMaxSize = TusDefaultMaxSize
}
if option.TusSessionExpiry <= 0 {
option.TusSessionExpiry = TusDefaultSessionExpiry
}
handlePath := option.TusBasePath + "/"
defaultMux.HandleFunc(handlePath, fs.filerGuard.WhiteList(requestIDMiddleware(fs.tusHandler)))
// Start background cleanup of expired TUS sessions (every hour)
fs.StartTusSessionCleanup(1 * time.Hour)
}
}
defaultMux.HandleFunc("/", fs.filerGuard.WhiteList(requestIDMiddleware(fs.filerHandler)))
}
if defaultMux != readonlyMux {
handleStaticResources(readonlyMux)
readonlyMux.HandleFunc("/healthz", requestIDMiddleware(fs.filerHealthzHandler))
readonlyMux.HandleFunc("/readyz", requestIDMiddleware(fs.filerHealthzHandler))
readonlyMux.HandleFunc("/", fs.filerGuard.WhiteList(requestIDMiddleware(fs.readonlyFilerHandler)))
}
existingNodes := fs.filer.ListExistingPeerUpdates(context.Background())
startFromTime := time.Now().Add(-filer.LogFlushInterval)
if isFresh {
glog.V(0).Infof("%s bootstrap from peers %+v", option.Host, existingNodes)
if err := fs.filer.MaybeBootstrapFromOnePeer(option.Host, existingNodes, startFromTime); err != nil {
glog.Fatalf("%s bootstrap from %+v: %v", option.Host, existingNodes, err)
}
}
v.SetDefault("filer.options.s3.empty_folder_cleanup_delay", "2m")
if d, err := time.ParseDuration(v.GetString("filer.options.s3.empty_folder_cleanup_delay")); err == nil {
fs.filer.EmptyFolderCleanupDelay = d
}
fs.filer.AggregateFromPeers(option.Host, existingNodes, startFromTime)
fs.filer.LoadFilerConf()
fs.filer.LoadRemoteStorageConfAndMapping()
grace.OnReload(fs.Reload)
fs.SetupDlmReplication()
fs.filer.Dlm.LockRing.SetTakeSnapshotCallback(fs.OnDlmChangeSnapshot)
if fs.CredentialManager != nil {
fs.CredentialManager.SetFilerAddressFunc(func() pb.ServerAddress {
return fs.option.Host
}, fs.grpcDialOption)
fs.CredentialManager.SetMasterClient(fs.filer.MasterClient, fs.grpcDialOption)
}
return fs, nil
}
func (fs *FilerServer) checkWithMaster() {
isConnected := false
for !isConnected {
fs.option.Masters.RefreshBySrvIfAvailable()
for _, master := range fs.option.Masters.GetInstances() {
readErr := operation.WithMasterServerClient(context.Background(), false, master, fs.grpcDialOption, func(masterClient master_pb.SeaweedClient) error {
resp, err := masterClient.GetMasterConfiguration(context.Background(), &master_pb.GetMasterConfigurationRequest{})
if err != nil {
return fmt.Errorf("get master %s configuration: %v", master, err)
}
fs.metricsAddress, fs.metricsIntervalSec = resp.MetricsAddress, int(resp.MetricsIntervalSeconds)
return nil
})
if readErr == nil {
isConnected = true
} else {
time.Sleep(7 * time.Second)
}
}
}
}
// Shutdown gracefully shuts down the filer server by waiting for in-flight uploads to complete.
// This prevents data corruption when the process receives SIGTERM during active uploads.
func (fs *FilerServer) Shutdown() {
glog.V(0).Infof("Shutting down filer")
if fs.posixLockSweeperStop != nil {
close(fs.posixLockSweeperStop)
}
fs.filer.Shutdown()
}
func (fs *FilerServer) Reload() {
glog.V(0).Infoln("Reload filer server...")
util.LoadConfiguration("security", false)
v := util.GetViper()
fs.filerGuard.UpdateSigningKeys(
v.GetString("jwt.filer_signing.key"),
v.GetInt("jwt.filer_signing.expires_after_seconds"),
v.GetString("jwt.filer_signing.read.key"),
v.GetInt("jwt.filer_signing.read.expires_after_seconds"),
)
fs.volumeGuard.UpdateSigningKeys(
v.GetString("jwt.signing.key"),
v.GetInt("jwt.signing.expires_after_seconds"),
v.GetString("jwt.signing.read.key"),
v.GetInt("jwt.signing.read.expires_after_seconds"),
)
util_http.ReloadJwtSigningReadConfig()
}