DockerCLI/vendor/github.com/docker/notary/trustmanager/keystore.go

326 lines
9.1 KiB
Go

package trustmanager
import (
"encoding/pem"
"fmt"
"path/filepath"
"strings"
"sync"
"github.com/Sirupsen/logrus"
"github.com/docker/notary"
store "github.com/docker/notary/storage"
"github.com/docker/notary/tuf/data"
"github.com/docker/notary/tuf/utils"
)
type keyInfoMap map[string]KeyInfo
// KeyInfo stores the role, path, and gun for a corresponding private key ID
// It is assumed that each private key ID is unique
type KeyInfo struct {
Gun string
Role string
}
// GenericKeyStore is a wrapper for Storage instances that provides
// translation between the []byte form and Public/PrivateKey objects
type GenericKeyStore struct {
store Storage
sync.Mutex
notary.PassRetriever
cachedKeys map[string]*cachedKey
keyInfoMap
}
// NewKeyFileStore returns a new KeyFileStore creating a private directory to
// hold the keys.
func NewKeyFileStore(baseDir string, p notary.PassRetriever) (*GenericKeyStore, error) {
fileStore, err := store.NewPrivateKeyFileStorage(baseDir, notary.KeyExtension)
if err != nil {
return nil, err
}
return NewGenericKeyStore(fileStore, p), nil
}
// NewKeyMemoryStore returns a new KeyMemoryStore which holds keys in memory
func NewKeyMemoryStore(p notary.PassRetriever) *GenericKeyStore {
memStore := store.NewMemoryStore(nil)
return NewGenericKeyStore(memStore, p)
}
// NewGenericKeyStore creates a GenericKeyStore wrapping the provided
// Storage instance, using the PassRetriever to enc/decrypt keys
func NewGenericKeyStore(s Storage, p notary.PassRetriever) *GenericKeyStore {
ks := GenericKeyStore{
store: s,
PassRetriever: p,
cachedKeys: make(map[string]*cachedKey),
keyInfoMap: make(keyInfoMap),
}
ks.loadKeyInfo()
return &ks
}
func generateKeyInfoMap(s Storage) map[string]KeyInfo {
keyInfoMap := make(map[string]KeyInfo)
for _, keyPath := range s.ListFiles() {
d, err := s.Get(keyPath)
if err != nil {
logrus.Error(err)
continue
}
keyID, keyInfo, err := KeyInfoFromPEM(d, keyPath)
if err != nil {
logrus.Error(err)
continue
}
keyInfoMap[keyID] = keyInfo
}
return keyInfoMap
}
// Attempts to infer the keyID, role, and GUN from the specified key path.
// Note that non-root roles can only be inferred if this is a legacy style filename: KEYID_ROLE.key
func inferKeyInfoFromKeyPath(keyPath string) (string, string, string) {
var keyID, role, gun string
keyID = filepath.Base(keyPath)
underscoreIndex := strings.LastIndex(keyID, "_")
// This is the legacy KEYID_ROLE filename
// The keyID is the first part of the keyname
// The keyRole is the second part of the keyname
// in a key named abcde_root, abcde is the keyID and root is the KeyAlias
if underscoreIndex != -1 {
role = keyID[underscoreIndex+1:]
keyID = keyID[:underscoreIndex]
}
if filepath.HasPrefix(keyPath, notary.RootKeysSubdir+"/") {
return keyID, data.CanonicalRootRole, ""
}
keyPath = strings.TrimPrefix(keyPath, notary.NonRootKeysSubdir+"/")
gun = getGunFromFullID(keyPath)
return keyID, role, gun
}
func getGunFromFullID(fullKeyID string) string {
keyGun := filepath.Dir(fullKeyID)
// If the gun is empty, Dir will return .
if keyGun == "." {
keyGun = ""
}
return keyGun
}
func (s *GenericKeyStore) loadKeyInfo() {
s.keyInfoMap = generateKeyInfoMap(s.store)
}
// GetKeyInfo returns the corresponding gun and role key info for a keyID
func (s *GenericKeyStore) GetKeyInfo(keyID string) (KeyInfo, error) {
if info, ok := s.keyInfoMap[keyID]; ok {
return info, nil
}
return KeyInfo{}, fmt.Errorf("Could not find info for keyID %s", keyID)
}
// AddKey stores the contents of a PEM-encoded private key as a PEM block
func (s *GenericKeyStore) AddKey(keyInfo KeyInfo, privKey data.PrivateKey) error {
var (
chosenPassphrase string
giveup bool
err error
pemPrivKey []byte
)
s.Lock()
defer s.Unlock()
if keyInfo.Role == data.CanonicalRootRole || data.IsDelegation(keyInfo.Role) || !data.ValidRole(keyInfo.Role) {
keyInfo.Gun = ""
}
name := filepath.Join(keyInfo.Gun, privKey.ID())
for attempts := 0; ; attempts++ {
chosenPassphrase, giveup, err = s.PassRetriever(name, keyInfo.Role, true, attempts)
if err == nil {
break
}
if giveup || attempts > 10 {
return ErrAttemptsExceeded{}
}
}
if chosenPassphrase != "" {
pemPrivKey, err = utils.EncryptPrivateKey(privKey, keyInfo.Role, keyInfo.Gun, chosenPassphrase)
} else {
pemPrivKey, err = utils.KeyToPEM(privKey, keyInfo.Role)
}
if err != nil {
return err
}
s.cachedKeys[name] = &cachedKey{alias: keyInfo.Role, key: privKey}
err = s.store.Set(filepath.Join(getSubdir(keyInfo.Role), name), pemPrivKey)
if err != nil {
return err
}
s.keyInfoMap[privKey.ID()] = keyInfo
return nil
}
// GetKey returns the PrivateKey given a KeyID
func (s *GenericKeyStore) GetKey(name string) (data.PrivateKey, string, error) {
s.Lock()
defer s.Unlock()
cachedKeyEntry, ok := s.cachedKeys[name]
if ok {
return cachedKeyEntry.key, cachedKeyEntry.alias, nil
}
keyBytes, _, keyAlias, err := getKey(s.store, name)
if err != nil {
return nil, "", err
}
// See if the key is encrypted. If its encrypted we'll fail to parse the private key
privKey, err := utils.ParsePEMPrivateKey(keyBytes, "")
if err != nil {
privKey, _, err = GetPasswdDecryptBytes(s.PassRetriever, keyBytes, name, string(keyAlias))
if err != nil {
return nil, "", err
}
}
s.cachedKeys[name] = &cachedKey{alias: keyAlias, key: privKey}
return privKey, keyAlias, nil
}
// ListKeys returns a list of unique PublicKeys present on the KeyFileStore, by returning a copy of the keyInfoMap
func (s *GenericKeyStore) ListKeys() map[string]KeyInfo {
return copyKeyInfoMap(s.keyInfoMap)
}
// RemoveKey removes the key from the keyfilestore
func (s *GenericKeyStore) RemoveKey(keyID string) error {
s.Lock()
defer s.Unlock()
_, filename, _, err := getKey(s.store, keyID)
switch err.(type) {
case ErrKeyNotFound, nil:
break
default:
return err
}
delete(s.cachedKeys, keyID)
err = s.store.Remove(filename) // removing a file that doesn't exist doesn't fail
if err != nil {
return err
}
// Remove this key from our keyInfo map if we removed from our filesystem
delete(s.keyInfoMap, filepath.Base(keyID))
return nil
}
// Name returns a user friendly name for the location this store
// keeps its data
func (s *GenericKeyStore) Name() string {
return s.store.Location()
}
// copyKeyInfoMap returns a deep copy of the passed-in keyInfoMap
func copyKeyInfoMap(keyInfoMap map[string]KeyInfo) map[string]KeyInfo {
copyMap := make(map[string]KeyInfo)
for keyID, keyInfo := range keyInfoMap {
copyMap[keyID] = KeyInfo{Role: keyInfo.Role, Gun: keyInfo.Gun}
}
return copyMap
}
// KeyInfoFromPEM attempts to get a keyID and KeyInfo from the filename and PEM bytes of a key
func KeyInfoFromPEM(pemBytes []byte, filename string) (string, KeyInfo, error) {
keyID, role, gun := inferKeyInfoFromKeyPath(filename)
if role == "" {
block, _ := pem.Decode(pemBytes)
if block == nil {
return "", KeyInfo{}, fmt.Errorf("could not decode PEM block for key %s", filename)
}
if keyRole, ok := block.Headers["role"]; ok {
role = keyRole
}
}
return keyID, KeyInfo{Gun: gun, Role: role}, nil
}
// getKey finds the key and role for the given keyID. It attempts to
// look both in the newer format PEM headers, and also in the legacy filename
// format. It returns: the key bytes, the filename it was found under, the role,
// and an error
func getKey(s Storage, keyID string) ([]byte, string, string, error) {
name := strings.TrimSpace(strings.TrimSuffix(filepath.Base(keyID), filepath.Ext(keyID)))
for _, file := range s.ListFiles() {
filename := filepath.Base(file)
if strings.HasPrefix(filename, name) {
d, err := s.Get(file)
if err != nil {
return nil, "", "", err
}
block, _ := pem.Decode(d)
if block != nil {
if role, ok := block.Headers["role"]; ok {
return d, file, role, nil
}
}
role := strings.TrimPrefix(filename, name+"_")
return d, file, role, nil
}
}
return nil, "", "", ErrKeyNotFound{KeyID: keyID}
}
// Assumes 2 subdirectories, 1 containing root keys and 1 containing TUF keys
func getSubdir(alias string) string {
if alias == data.CanonicalRootRole {
return notary.RootKeysSubdir
}
return notary.NonRootKeysSubdir
}
// GetPasswdDecryptBytes gets the password to decrypt the given pem bytes.
// Returns the password and private key
func GetPasswdDecryptBytes(passphraseRetriever notary.PassRetriever, pemBytes []byte, name, alias string) (data.PrivateKey, string, error) {
var (
passwd string
privKey data.PrivateKey
)
for attempts := 0; ; attempts++ {
var (
giveup bool
err error
)
if attempts > 10 {
return nil, "", ErrAttemptsExceeded{}
}
passwd, giveup, err = passphraseRetriever(name, alias, false, attempts)
// Check if the passphrase retriever got an error or if it is telling us to give up
if giveup || err != nil {
return nil, "", ErrPasswordInvalid{}
}
// Try to convert PEM encoded bytes back to a PrivateKey using the passphrase
privKey, err = utils.ParsePEMPrivateKey(pemBytes, passwd)
if err == nil {
// We managed to parse the PrivateKey. We've succeeded!
break
}
}
return privKey, passwd, nil
}