Ensure that OctaviaServerCertsKeyPassphrase is 32-byte long

Conflicts:
      tripleo_common/utils/passwords.py

Related-Bug: #1833942

Change-Id: Ibcdbe2605a7cabe3a5ef8245b4460c8f70220989
(cherry picked from commit de2ab55824)
(cherry picked from commit 94620dd5e6)
(cherry picked from commit 35913d6266)

releasenotes/notes/fix-generated-server_certs_key_passphrase-60cba4653109992c.yaml

@@ -0,0 +1,5 @@
+---
+fixes:
+  - The passphrase for config option 'server_certs_key_passphrase', is used as
+    a Fernet key in Octavia and thus must be 32 bytes long. TripleO will now
+    auto-generate 32 bytes long passphrase for OctaviaServerCertsKeyPassphrase.

tripleo_common/tests/utils/test_passwords.py

@@ -73,6 +73,7 @@ class TestPasswords(base.TestCase):
 
         self.assertNotEqual(value['KeystoneCredential0'],
                             value['KeystoneCredential1'])
+        self.assertEqual(len(value['OctaviaServerCertsKeyPassphrase']), 32)
 
     def test_create_ssh_keypair(self):
 

tripleo_common/utils/passwords.py

@@ -90,6 +90,9 @@ def generate_passwords(mistralclient=None, stack_env=None):
         elif name.startswith("HeatAuthEncryptionKey"):
             passwords[name] = passutils.generate_password(
                 size=32)
+        elif name.startswith("OctaviaServerCertsKeyPassphrase"):
+            passwords[name] = passutils.generate_password(
+                size=32)
         else:
             passwords[name] = passutils.generate_password(
                 size=_MIN_PASSWORD_SIZE)