open-vault/builtin/logical/database/backend.go
Tom Proctor aa50e42fca
Support version selection for database plugins (#16982)
* Support version selection for database plugins
* Don't consider unversioned plugins for version selection algorithm
* Added version to 'plugin not found' error
* Add PluginFactoryVersion function to avoid changing sdk/ API
2022-09-09 17:32:28 +01:00

435 lines
12 KiB
Go

package database
import (
"context"
"fmt"
"net/rpc"
"strings"
"sync"
"time"
"github.com/armon/go-metrics"
log "github.com/hashicorp/go-hclog"
"github.com/hashicorp/go-secure-stdlib/strutil"
"github.com/hashicorp/go-uuid"
"github.com/hashicorp/vault/helper/metricsutil"
"github.com/hashicorp/vault/internalshared/configutil"
v4 "github.com/hashicorp/vault/sdk/database/dbplugin"
v5 "github.com/hashicorp/vault/sdk/database/dbplugin/v5"
"github.com/hashicorp/vault/sdk/database/helper/dbutil"
"github.com/hashicorp/vault/sdk/framework"
"github.com/hashicorp/vault/sdk/helper/locksutil"
"github.com/hashicorp/vault/sdk/logical"
"github.com/hashicorp/vault/sdk/queue"
)
const (
databaseConfigPath = "config/"
databaseRolePath = "role/"
databaseStaticRolePath = "static-role/"
minRootCredRollbackAge = 1 * time.Minute
)
type dbPluginInstance struct {
sync.RWMutex
database databaseVersionWrapper
id string
name string
closed bool
}
func (dbi *dbPluginInstance) Close() error {
dbi.Lock()
defer dbi.Unlock()
if dbi.closed {
return nil
}
dbi.closed = true
return dbi.database.Close()
}
func Factory(ctx context.Context, conf *logical.BackendConfig) (logical.Backend, error) {
b := Backend(conf)
if err := b.Setup(ctx, conf); err != nil {
return nil, err
}
b.credRotationQueue = queue.New()
// Load queue and kickoff new periodic ticker
go b.initQueue(b.queueCtx, conf, conf.System.ReplicationState())
// collect metrics on number of plugin instances
var err error
b.gaugeCollectionProcess, err = metricsutil.NewGaugeCollectionProcess(
[]string{"secrets", "database", "backend", "pluginInstances", "count"},
[]metricsutil.Label{},
b.collectPluginInstanceGaugeValues,
metrics.Default(),
configutil.UsageGaugeDefaultPeriod, // TODO: add config settings for these, or add plumbing to the main config settings
configutil.MaximumGaugeCardinalityDefault,
b.logger)
if err != nil {
return nil, err
}
go b.gaugeCollectionProcess.Run()
return b, nil
}
func Backend(conf *logical.BackendConfig) *databaseBackend {
var b databaseBackend
b.Backend = &framework.Backend{
Help: strings.TrimSpace(backendHelp),
PathsSpecial: &logical.Paths{
LocalStorage: []string{
framework.WALPrefix,
},
SealWrapStorage: []string{
"config/*",
"static-role/*",
},
},
Paths: framework.PathAppend(
[]*framework.Path{
pathListPluginConnection(&b),
pathConfigurePluginConnection(&b),
pathResetConnection(&b),
},
pathListRoles(&b),
pathRoles(&b),
pathCredsCreate(&b),
pathRotateRootCredentials(&b),
),
Secrets: []*framework.Secret{
secretCreds(&b),
},
Clean: b.clean,
Invalidate: b.invalidate,
WALRollback: b.walRollback,
WALRollbackMinAge: minRootCredRollbackAge,
BackendType: logical.TypeLogical,
}
b.logger = conf.Logger
b.connections = make(map[string]*dbPluginInstance)
b.queueCtx, b.cancelQueueCtx = context.WithCancel(context.Background())
b.roleLocks = locksutil.CreateLocks()
return &b
}
func (b *databaseBackend) collectPluginInstanceGaugeValues(context.Context) ([]metricsutil.GaugeLabelValues, error) {
// copy the map so we can release the lock
connMapCopy := func() map[string]*dbPluginInstance {
b.connLock.RLock()
defer b.connLock.RUnlock()
mapCopy := map[string]*dbPluginInstance{}
for k, v := range b.connections {
mapCopy[k] = v
}
return mapCopy
}()
counts := map[string]int{}
for _, v := range connMapCopy {
dbType, err := v.database.Type()
if err != nil {
// there's a chance this will already be closed since we don't hold the lock
continue
}
if _, ok := counts[dbType]; !ok {
counts[dbType] = 0
}
counts[dbType] += 1
}
var gauges []metricsutil.GaugeLabelValues
for k, v := range counts {
gauges = append(gauges, metricsutil.GaugeLabelValues{Labels: []metricsutil.Label{{Name: "dbType", Value: k}}, Value: float32(v)})
}
return gauges, nil
}
type databaseBackend struct {
// connLock is used to synchronize access to the connections map
connLock sync.RWMutex
// connections holds configured database connections by config name
connections map[string]*dbPluginInstance
logger log.Logger
*framework.Backend
// credRotationQueue is an in-memory priority queue used to track Static Roles
// that require periodic rotation. Backends will have a PriorityQueue
// initialized on setup, but only backends that are mounted by a primary
// server or mounted as a local mount will perform the rotations.
credRotationQueue *queue.PriorityQueue
// queueCtx is the context for the priority queue
queueCtx context.Context
// cancelQueueCtx is used to terminate the background ticker
cancelQueueCtx context.CancelFunc
// roleLocks is used to lock modifications to roles in the queue, to ensure
// concurrent requests are not modifying the same role and possibly causing
// issues with the priority queue.
roleLocks []*locksutil.LockEntry
// the running gauge collection process
gaugeCollectionProcess *metricsutil.GaugeCollectionProcess
gaugeCollectionProcessStop sync.Once
}
func (b *databaseBackend) connGet(name string) *dbPluginInstance {
b.connLock.RLock()
defer b.connLock.RUnlock()
return b.connections[name]
}
func (b *databaseBackend) connPop(name string) *dbPluginInstance {
b.connLock.Lock()
defer b.connLock.Unlock()
dbi, ok := b.connections[name]
if ok {
delete(b.connections, name)
}
return dbi
}
func (b *databaseBackend) connPopIfEqual(name, id string) *dbPluginInstance {
b.connLock.Lock()
defer b.connLock.Unlock()
dbi, ok := b.connections[name]
if ok && dbi.id == id {
delete(b.connections, name)
return dbi
}
return nil
}
func (b *databaseBackend) connPut(name string, newDbi *dbPluginInstance) *dbPluginInstance {
b.connLock.Lock()
defer b.connLock.Unlock()
dbi := b.connections[name]
b.connections[name] = newDbi
return dbi
}
func (b *databaseBackend) connClear() map[string]*dbPluginInstance {
b.connLock.Lock()
defer b.connLock.Unlock()
old := b.connections
b.connections = make(map[string]*dbPluginInstance)
return old
}
func (b *databaseBackend) DatabaseConfig(ctx context.Context, s logical.Storage, name string) (*DatabaseConfig, error) {
entry, err := s.Get(ctx, fmt.Sprintf("config/%s", name))
if err != nil {
return nil, fmt.Errorf("failed to read connection configuration: %w", err)
}
if entry == nil {
return nil, fmt.Errorf("failed to find entry for connection with name: %q", name)
}
var config DatabaseConfig
if err := entry.DecodeJSON(&config); err != nil {
return nil, err
}
return &config, nil
}
type upgradeStatements struct {
// This json tag has a typo in it, the new version does not. This
// necessitates this upgrade logic.
CreationStatements string `json:"creation_statments"`
RevocationStatements string `json:"revocation_statements"`
RollbackStatements string `json:"rollback_statements"`
RenewStatements string `json:"renew_statements"`
}
type upgradeCheck struct {
// This json tag has a typo in it, the new version does not. This
// necessitates this upgrade logic.
Statements *upgradeStatements `json:"statments,omitempty"`
}
func (b *databaseBackend) Role(ctx context.Context, s logical.Storage, roleName string) (*roleEntry, error) {
return b.roleAtPath(ctx, s, roleName, databaseRolePath)
}
func (b *databaseBackend) StaticRole(ctx context.Context, s logical.Storage, roleName string) (*roleEntry, error) {
return b.roleAtPath(ctx, s, roleName, databaseStaticRolePath)
}
func (b *databaseBackend) roleAtPath(ctx context.Context, s logical.Storage, roleName string, pathPrefix string) (*roleEntry, error) {
entry, err := s.Get(ctx, pathPrefix+roleName)
if err != nil {
return nil, err
}
if entry == nil {
return nil, nil
}
var upgradeCh upgradeCheck
if err := entry.DecodeJSON(&upgradeCh); err != nil {
return nil, err
}
var result roleEntry
if err := entry.DecodeJSON(&result); err != nil {
return nil, err
}
switch {
case upgradeCh.Statements != nil:
var stmts v4.Statements
if upgradeCh.Statements.CreationStatements != "" {
stmts.Creation = []string{upgradeCh.Statements.CreationStatements}
}
if upgradeCh.Statements.RevocationStatements != "" {
stmts.Revocation = []string{upgradeCh.Statements.RevocationStatements}
}
if upgradeCh.Statements.RollbackStatements != "" {
stmts.Rollback = []string{upgradeCh.Statements.RollbackStatements}
}
if upgradeCh.Statements.RenewStatements != "" {
stmts.Renewal = []string{upgradeCh.Statements.RenewStatements}
}
result.Statements = stmts
}
result.Statements.Revocation = strutil.RemoveEmpty(result.Statements.Revocation)
// For backwards compatibility, copy the values back into the string form
// of the fields
result.Statements = dbutil.StatementCompatibilityHelper(result.Statements)
return &result, nil
}
func (b *databaseBackend) invalidate(ctx context.Context, key string) {
switch {
case strings.HasPrefix(key, databaseConfigPath):
name := strings.TrimPrefix(key, databaseConfigPath)
b.ClearConnection(name)
}
}
func (b *databaseBackend) GetConnection(ctx context.Context, s logical.Storage, name string) (*dbPluginInstance, error) {
config, err := b.DatabaseConfig(ctx, s, name)
if err != nil {
return nil, err
}
return b.GetConnectionWithConfig(ctx, name, config)
}
func (b *databaseBackend) GetConnectionWithConfig(ctx context.Context, name string, config *DatabaseConfig) (*dbPluginInstance, error) {
dbi := b.connGet(name)
if dbi != nil {
return dbi, nil
}
id, err := uuid.GenerateUUID()
if err != nil {
return nil, err
}
dbw, err := newDatabaseWrapper(ctx, config.PluginName, config.PluginVersion, b.System(), b.logger)
if err != nil {
return nil, fmt.Errorf("unable to create database instance: %w", err)
}
initReq := v5.InitializeRequest{
Config: config.ConnectionDetails,
VerifyConnection: true,
}
_, err = dbw.Initialize(ctx, initReq)
if err != nil {
dbw.Close()
return nil, err
}
dbi = &dbPluginInstance{
database: dbw,
id: id,
name: name,
}
oldConn := b.connPut(name, dbi)
if oldConn != nil {
err := oldConn.Close()
if err != nil {
b.Logger().Warn("Error closing database connection", "error", err)
}
}
return dbi, nil
}
// ClearConnection closes the database connection and
// removes it from the b.connections map.
func (b *databaseBackend) ClearConnection(name string) error {
db := b.connPop(name)
if db != nil {
// Ignore error here since the database client is always killed
db.Close()
}
return nil
}
// ClearConnectionId closes the database connection with a specific id and
// removes it from the b.connections map.
func (b *databaseBackend) ClearConnectionId(name, id string) error {
db := b.connPopIfEqual(name, id)
if db != nil {
// Ignore error here since the database client is always killed
db.Close()
}
return nil
}
func (b *databaseBackend) CloseIfShutdown(db *dbPluginInstance, err error) {
// Plugin has shutdown, close it so next call can reconnect.
switch err {
case rpc.ErrShutdown, v4.ErrPluginShutdown, v5.ErrPluginShutdown:
// Put this in a goroutine so that requests can run with the read or write lock
// and simply defer the unlock. Since we are attaching the instance and matching
// the id in the connection map, we can safely do this.
go func() {
db.Close()
// Delete the connection if it is still active.
b.connPopIfEqual(db.name, db.id)
}()
}
}
// clean closes all connections from all database types
// and cancels any rotation queue loading operation.
func (b *databaseBackend) clean(_ context.Context) {
// kill the queue and terminate the background ticker
if b.cancelQueueCtx != nil {
b.cancelQueueCtx()
}
connections := b.connClear()
for _, db := range connections {
go db.Close()
}
b.gaugeCollectionProcessStop.Do(func() {
if b.gaugeCollectionProcess != nil {
b.gaugeCollectionProcess.Stop()
}
b.gaugeCollectionProcess = nil
})
}
const backendHelp = `
The database backend supports using many different databases
as secret backends, including but not limited to:
cassandra, mssql, mysql, postgres
After mounting this backend, configure it using the endpoints within
the "database/config/" path.
`