Fix 'vault rekey' with vault secret env var

if ANSIBLE_VAULT_PASSWORD_FILE is set, 'ansible-vault rekey myvault.yml'
will fail to prompt for the new vault password file, and will use
None.

Fix is to split out 'ask_vault_passwords' into 'ask_vault_passwords'
and 'ask_new_vault_passwords' to make the logic simpler. And then
make sure new_vault_pass is always set for 'rekey', and if not, then
call ask_new_vault_passwords() to set it.

ask_vault_passwords() would return values for vault_pass and new
vault_pass, and vault cli previously would not prompt for new_vault_pass
if there was a vault_pass set via a vault password file.

Fixes #18247

lib/ansible/cli/__init__.py

@@ -161,33 +161,37 @@ class CLI(with_metaclass(ABCMeta, object)):
                 display.display(u"No config file found; using defaults")
 
     @staticmethod
-    def ask_vault_passwords(ask_new_vault_pass=False, rekey=False):
+    def ask_vault_passwords():
         ''' prompt for vault password and/or password change '''
 
         vault_pass = None
-        new_vault_pass = None
         try:
-            if rekey or not ask_new_vault_pass:
-                vault_pass = getpass.getpass(prompt="Vault password: ")
+            vault_pass = getpass.getpass(prompt="Vault password: ")
 
-            if ask_new_vault_pass:
-                new_vault_pass = getpass.getpass(prompt="New Vault password: ")
-                new_vault_pass2 = getpass.getpass(prompt="Confirm New Vault password: ")
-                if new_vault_pass != new_vault_pass2:
-                    raise AnsibleError("Passwords do not match")
         except EOFError:
             pass
 
         # enforce no newline chars at the end of passwords
         if vault_pass:
             vault_pass = to_bytes(vault_pass, errors='strict', nonstring='simplerepr').strip()
+
+        return vault_pass
+
+    @staticmethod
+    def ask_new_vault_passwords():
+        new_vault_pass = None
+        try:
+            new_vault_pass = getpass.getpass(prompt="New Vault password: ")
+            new_vault_pass2 = getpass.getpass(prompt="Confirm New Vault password: ")
+            if new_vault_pass != new_vault_pass2:
+                raise AnsibleError("Passwords do not match")
+        except EOFError:
+            pass
+
         if new_vault_pass:
             new_vault_pass = to_bytes(new_vault_pass, errors='strict', nonstring='simplerepr').strip()
 
-        if ask_new_vault_pass and not rekey:
-            vault_pass = new_vault_pass
-
-        return vault_pass, new_vault_pass
+        return new_vault_pass
 
     def ask_passwords(self):
         ''' prompt for connection and become passwords if needed '''

lib/ansible/cli/adhoc.py

@@ -118,7 +118,7 @@ class AdHocCLI(CLI):
             vault_pass = CLI.read_vault_password_file(self.options.vault_password_file, loader=loader)
             loader.set_vault_password(vault_pass)
         elif self.options.ask_vault_pass:
-            vault_pass = self.ask_vault_passwords()[0]
+            vault_pass = self.ask_vault_passwords()
             loader.set_vault_password(vault_pass)
 
         variable_manager = VariableManager()

lib/ansible/cli/playbook.py

@@ -116,7 +116,7 @@ class PlaybookCLI(CLI):
             vault_pass = CLI.read_vault_password_file(self.options.vault_password_file, loader=loader)
             loader.set_vault_password(vault_pass)
         elif self.options.ask_vault_pass:
-            vault_pass = self.ask_vault_passwords()[0]
+            vault_pass = self.ask_vault_passwords()
             loader.set_vault_password(vault_pass)
 
         # create the variable manager, which will be shared throughout

lib/ansible/cli/vault.py

@@ -101,21 +101,23 @@ class VaultCLI(CLI):
         if self.options.vault_password_file:
             # read vault_pass from a file
             self.vault_pass = CLI.read_vault_password_file(self.options.vault_password_file, loader)
-        else:
-            newpass = False
-            rekey = False
-            if not self.options.new_vault_password_file:
-                newpass = (self.action in ['create', 'rekey', 'encrypt'])
-                rekey = (self.action == 'rekey')
-            self.vault_pass, self.new_vault_pass = self.ask_vault_passwords(ask_new_vault_pass=newpass, rekey=rekey)
 
         if self.options.new_vault_password_file:
             # for rekey only
             self.new_vault_pass = CLI.read_vault_password_file(self.options.new_vault_password_file, loader)
 
+        if not self.vault_pass or self.options.ask_vault_pass:
+            self.vault_pass = self.ask_vault_passwords()
+
         if not self.vault_pass:
             raise AnsibleOptionsError("A password is required to use Ansible's Vault")
 
+        if self.action == 'rekey':
+            if not self.new_vault_pass:
+                self.new_vault_pass = self.ask_new_vault_passwords()
+            if not self.new_vault_pass:
+                raise AnsibleOptionsError("A password is required to rekey Ansible's Vault")
+
         self.editor = VaultEditor(self.vault_pass)
 
         self.execute()

lib/ansible/parsing/vault/__init__.py

@@ -486,6 +486,10 @@ class VaultEditor:
         except AnsibleError as e:
             raise AnsibleError("%s for %s" % (to_bytes(e),to_bytes(filename)))
 
+        # This is more or less an assert, see #18247
+        if new_password is None:
+            raise AnsibleError('The value for the new_password to rekey %s with is not valid' % filename)
+
         new_vault = VaultLib(new_password)
         new_ciphertext = new_vault.encrypt(plaintext)