Merge branch 'v0-16-3-branch-7705' into v0-16-3-branch

Author: Roasbeef

docs/release-notes/release-notes-0.16.3.md

@@ -6,5 +6,12 @@ Optimized [mempool
 management](https://github.com/lightningnetwork/lnd/pull/7681) to lower the CPU
 usage.
 
+## Bug Fixes
+
+* [Re-encrypt/regenerate](https://github.com/lightningnetwork/lnd/pull/7705)
+  all macaroon DB root keys on `ChangePassword`/`GenerateNewRootKey`
+  respectively.
+
 # Contributors (Alphabetical Order)
+* Elle Mouton
 * Yong Yu

macaroons/store.go

@@ -54,6 +54,10 @@ var (
 	// ErrEncKeyNotFound specifies that there was no encryption key found
 	// even if one was expected to be generated.
 	ErrEncKeyNotFound = fmt.Errorf("macaroon encryption key not found")
+
+	// ErrDefaultRootKeyNotFound is returned when the default root key is
+	// not found in the DB when it is expected to be.
+	ErrDefaultRootKeyNotFound = fmt.Errorf("default root key not found")
 )
 
 // RootKeyStorage implements the bakery.RootKeyStorage interface.
@@ -140,8 +144,8 @@ func (r *RootKeyStorage) CreateUnlock(password *[]byte) error {
 	}, func() {})
 }
 
-// ChangePassword decrypts the macaroon root key with the old password and then
-// encrypts it again with the new password.
+// ChangePassword decrypts all the macaroon root keys with the old password and
+// then encrypts them again with the new password.
 func (r *RootKeyStorage) ChangePassword(oldPw, newPw []byte) error {
 	// We need the store to already be unlocked. With this we can make sure
 	// that there already is a key in the DB.
@@ -159,19 +163,18 @@ func (r *RootKeyStorage) ChangePassword(oldPw, newPw []byte) error {
 		if bucket == nil {
 			return ErrRootKeyBucketNotFound
 		}
-		encKeyDb := bucket.Get(encryptionKeyID)
-		rootKeyDb := bucket.Get(DefaultRootKeyID)
 
-		// Both the encryption key and the root key must be present
-		// otherwise we are in the wrong state to change the password.
-		if len(encKeyDb) == 0 || len(rootKeyDb) == 0 {
+		// The encryption key must be present, otherwise we are in the
+		// wrong state to change the password.
+		encKeyDB := bucket.Get(encryptionKeyID)
+		if len(encKeyDB) == 0 {
 			return ErrEncKeyNotFound
 		}
 
 		// Unmarshal parameters for old encryption key and derive the
 		// old key with them.
 		encKeyOld := &snacl.SecretKey{}
-		err := encKeyOld.Unmarshal(encKeyDb)
+		err := encKeyOld.Unmarshal(encKeyDB)
 		if err != nil {
 			return err
 		}
@@ -188,21 +191,42 @@ func (r *RootKeyStorage) ChangePassword(oldPw, newPw []byte) error {
 			return err
 		}
 
-		// Now try to decrypt the root key with the old encryption key,
-		// encrypt it with the new one and then store it in the DB.
-		decryptedKey, err := encKeyOld.Decrypt(rootKeyDb)
-		if err != nil {
-			return err
-		}
-		rootKey := make([]byte, len(decryptedKey))
-		copy(rootKey, decryptedKey)
-		encryptedKey, err := encKeyNew.Encrypt(rootKey)
+		// foundDefaultRootKey is used to keep track of if we have
+		// found and re-encrypted the default root key so that we can
+		// return an error if it is not found.
+		var foundDefaultRootKey bool
+		err = bucket.ForEach(func(k, v []byte) error {
+			// Skip the key if it is the encryption key ID since
+			// we do not want to re-encrypt this.
+			if bytes.Equal(k, encryptionKeyID) {
+				return nil
+			}
+
+			if bytes.Equal(k, DefaultRootKeyID) {
+				foundDefaultRootKey = true
+			}
+
+			// Now try to decrypt the root key with the old
+			// encryption key, encrypt it with the new one and then
+			// store it in the DB.
+			decryptedKey, err := encKeyOld.Decrypt(v)
+			if err != nil {
+				return err
+			}
+
+			encryptedKey, err := encKeyNew.Encrypt(decryptedKey)
+			if err != nil {
+				return err
+			}
+
+			return bucket.Put(k, encryptedKey)
+		})
 		if err != nil {
 			return err
 		}
-		err = bucket.Put(DefaultRootKeyID, encryptedKey)
-		if err != nil {
-			return err
+
+		if !foundDefaultRootKey {
+			return ErrDefaultRootKeyNotFound
 		}
 
 		// Finally, store the new encryption key parameters in the DB
@@ -325,10 +349,34 @@ func (r *RootKeyStorage) GenerateNewRootKey() error {
 		if bucket == nil {
 			return ErrRootKeyBucketNotFound
 		}
+
+		// The default root key should be created even if it does not
+		// yet exist, so we do this separately from the rest of the
+		// root keys.
 		_, err := generateAndStoreNewRootKey(
 			bucket, DefaultRootKeyID, r.encKey,
 		)
-		return err
+		if err != nil {
+			return err
+		}
+
+		// Now iterate over all the other root keys that may exist
+		// and re-generate each of them.
+		return bucket.ForEach(func(k, v []byte) error {
+			if bytes.Equal(k, encryptionKeyID) {
+				return nil
+			}
+
+			if bytes.Equal(k, DefaultRootKeyID) {
+				return nil
+			}
+
+			_, err := generateAndStoreNewRootKey(
+				bucket, k, r.encKey,
+			)
+
+			return err
+		})
 	}, func() {})
 }
 

macaroons/store_test.go

@@ -16,6 +16,10 @@ var (
 	defaultRootKeyIDContext = macaroons.ContextWithRootKeyID(
 		context.Background(), macaroons.DefaultRootKeyID,
 	)
+
+	nonDefaultRootKeyIDContext = macaroons.ContextWithRootKeyID(
+		context.Background(), []byte{1},
+	)
 )
 
 // newTestStore creates a new bolt DB in a temporary directory and then
@@ -131,32 +135,42 @@ func TestStore(t *testing.T) {
 	require.Equal(t, rootID, id)
 }
 
-// TestStoreGenerateNewRootKey tests that a root key can be replaced with a new
-// one in the store without changing the password.
+// TestStoreGenerateNewRootKey tests that root keys can be replaced with new
+// ones in the store without changing the password.
 func TestStoreGenerateNewRootKey(t *testing.T) {
 	_, store := newTestStore(t)
 
 	// The store must be unlocked to replace the root key.
 	err := store.GenerateNewRootKey()
 	require.Equal(t, macaroons.ErrStoreLocked, err)
 
-	// Unlock the store and read the current key.
+	// Unlock the store.
 	pw := []byte("weks")
 	err = store.CreateUnlock(&pw)
 	require.NoError(t, err)
-	oldRootKey, _, err := store.RootKey(defaultRootKeyIDContext)
+
+	// Read the default root key.
+	oldRootKey1, _, err := store.RootKey(defaultRootKeyIDContext)
 	require.NoError(t, err)
 
-	// Replace the root key with a new random key.
+	// Read the non-default root-key.
+	oldRootKey2, _, err := store.RootKey(nonDefaultRootKeyIDContext)
+	require.NoError(t, err)
+
+	// Replace the root keys with new random keys.
 	err = store.GenerateNewRootKey()
 	require.NoError(t, err)
 
-	// Finally, read the root key from the DB and compare it to the one
+	// Finally, read both root keys from the DB and compare them to the ones
 	// we got returned earlier. This makes sure that the encryption/
 	// decryption of the key in the DB worked as expected too.
-	newRootKey, _, err := store.RootKey(defaultRootKeyIDContext)
+	newRootKey1, _, err := store.RootKey(defaultRootKeyIDContext)
 	require.NoError(t, err)
-	require.NotEqual(t, oldRootKey, newRootKey)
+	require.NotEqual(t, oldRootKey1, newRootKey1)
+
+	newRootKey2, _, err := store.RootKey(nonDefaultRootKeyIDContext)
+	require.NoError(t, err)
+	require.NotEqual(t, oldRootKey2, newRootKey2)
 }
 
 // TestStoreSetRootKey tests that a root key can be set to a specified value.
@@ -195,20 +209,25 @@ func TestStoreSetRootKey(t *testing.T) {
 }
 
 // TestStoreChangePassword tests that the password for the store can be changed
-// without changing the root key.
+// without changing the root keys.
 func TestStoreChangePassword(t *testing.T) {
 	tempDir, store := newTestStore(t)
 
-	// The store must be unlocked to replace the root key.
+	// The store must be unlocked to replace the root keys.
 	err := store.ChangePassword(nil, nil)
 	require.Equal(t, macaroons.ErrStoreLocked, err)
 
-	// Unlock the DB and read the current root key. This will need to stay
-	// the same after changing the password for the test to succeed.
+	// Unlock the DB and read the current default root key and one other
+	// non-default root key. Both of these should stay the same after
+	// changing the password for the test to succeed.
 	pw := []byte("weks")
 	err = store.CreateUnlock(&pw)
 	require.NoError(t, err)
-	rootKey, _, err := store.RootKey(defaultRootKeyIDContext)
+
+	rootKey1, _, err := store.RootKey(defaultRootKeyIDContext)
+	require.NoError(t, err)
+
+	rootKey2, _, err := store.RootKey(nonDefaultRootKeyIDContext)
 	require.NoError(t, err)
 
 	// Both passwords must be set.
@@ -242,9 +261,13 @@ func TestStoreChangePassword(t *testing.T) {
 	err = store.CreateUnlock(&newPw)
 	require.NoError(t, err)
 
-	// Finally read the root key from the DB using the new password and
-	// make sure the root key stayed the same.
-	rootKeyDb, _, err := store.RootKey(defaultRootKeyIDContext)
+	// Finally, read the root keys from the DB using the new password and
+	// make sure that both root keys stayed the same.
+	rootKeyDB1, _, err := store.RootKey(defaultRootKeyIDContext)
+	require.NoError(t, err)
+	require.Equal(t, rootKey1, rootKeyDB1)
+
+	rootKeyDB2, _, err := store.RootKey(nonDefaultRootKeyIDContext)
 	require.NoError(t, err)
-	require.Equal(t, rootKey, rootKeyDb)
+	require.Equal(t, rootKey2, rootKeyDB2)
 }