Merge pull request #252 from srivasta/master

[admin_user]: Added support for password and static pubkey auth

bootstrapvz/plugins/admin_user/README.rst

@@ -2,11 +2,29 @@ Admin user
 ----------
 
 This plugin creates a user with passwordless sudo privileges. It also
-disables the SSH root login. If the EC2 init scripts are installed, the
-script for fetching the SSH authorized keys will be adjust to match the
-username specified.
+disables the SSH root login. There are three ways to grant access to
+the admin user:
+-  Set a password for the user, or
+-  Provide a ssh public key to allow remote ssh login, or
+-  Use the EC2 public key (EC2 machines only)
+
+If a password is provided, this plugin sets the admin password. This
+also re-enables password login (off by default in Jessie).
+
+If the optional argument pubkey is present (it should be a full path
+to a ssh public key), it will ensure that the ssh public key is used
+to set up password less remote login for the admin user.
+
+Only one of these options (password, or pubkey) may be specified.
+
+If neither the password not a ssh public key location are specified,
+and if the EC2 init scripts are installed, the script for fetching the
+SSH authorized keys will be adjust to match the username specified.
 
 Settings
 ~~~~~~~~
 
 -  ``username``: The username of the account to create. ``required``
+-  ``password``: An optional password for the account to create. ``optional``
+-  ``pubkey``:   The full path to an ssh public key to allow
+   remote access into the admin account. ``optional``

bootstrapvz/plugins/admin_user/__init__.py

@@ -4,19 +4,33 @@ def validate_manifest(data, validator, error):
 	import os.path
 	schema_path = os.path.normpath(os.path.join(os.path.dirname(__file__), 'manifest-schema.yml'))
 	validator(data, schema_path)
+	if ('password' in data['plugins']['admin_user'] and 'pubkey' in data['plugins']['admin_user']):
+		msg = 'passwd and pubkey are mutually exclusive.'
+		error(msg, ['plugins', 'admin_user'])
+	if 'pubkey' in data['plugins']['admin_user']:
+		full_path = data['plugins']['admin_user']['pubkey']
+		if not os.path.exists(full_path):
+	    		msg = 'Could not find public key at %s' % full_path
+	    		error(msg, ['plugins', 'admin_user'])
 
 
 def resolve_tasks(taskset, manifest):
 	import tasks
 	from bootstrapvz.common.tasks import ssh
-	from bootstrapvz.providers.ec2.tasks import initd
-	if initd.AddEC2InitScripts in taskset:
-		taskset.add(tasks.AdminUserCredentials)
 
 	from bootstrapvz.common.releases import jessie
 	if manifest.release < jessie:
 		taskset.update([ssh.DisableRootLogin])
 
+	if 'password' in manifest.plugins['admin_user']:
+		taskset.discard(ssh.DisableSSHPasswordAuthentication)
+		taskset.add(tasks.AdminUserCredentialsPassword)
+	else:
+		if 'pubkey' in manifest.plugins['admin_user']:
+			taskset.add(tasks.AdminUserCredentialsPublicKey)
+		else:
+			taskset.add(tasks.AdminUserCredentialsEc2)
+
 	taskset.update([tasks.AddSudoPackage,
 	                tasks.CreateAdminUser,
 	                tasks.PasswordlessSudo,

bootstrapvz/plugins/admin_user/manifest-schema.yml

@@ -10,5 +10,11 @@ properties:
         type: object
         properties:
           username: {type: string}
+          password: {type: string}
+          pubkey: {$ref: '#/definitions/absolute_path'}
         required: [username]
         additionalProperties: false
+definitions:
+  absolute_path:
+    pattern: ^/[^\0]+$
+    type: string

bootstrapvz/plugins/admin_user/tasks.py

@@ -1,6 +1,9 @@
 from bootstrapvz.base import Task
 from bootstrapvz.common import phases
 from bootstrapvz.common.tasks.initd import InstallInitScripts
+from bootstrapvz.providers.ec2.tasks.initd import AddEC2InitScripts
+
+import logging
 import os
 
 
@@ -41,14 +44,85 @@ class PasswordlessSudo(Task):
 		os.chmod(sudo_admin_path, ug_read_only)
 
 
-class AdminUserCredentials(Task):
-	description = 'Modifying ec2-get-credentials to copy the ssh public key to the admin user'
+class AdminUserCredentialsPassword(Task):
+	description = 'Set up access credentials for the admin user with a given password'
 	phase = phases.system_modification
-	predecessors = [InstallInitScripts]
+	predecessors = [InstallInitScripts, CreateAdminUser]
+
+	@classmethod
+	def run(cls, info):
+		from bootstrapvz.common.tools import log_check_call
+		log = logging.getLogger(__name__)
+
+		log.debug('Setting the password for the admin user.')
+		log_check_call(
+			['chroot', info.root, 'chpasswd'],
+			info.manifest.plugins['admin_user']['username'] +
+			':' + info.manifest.plugins['admin_user']['password']
+		)
+		return
+
+
+class AdminUserCredentialsPublicKey(Task):
+	description = 'Set up access credentials for the admin user with a given public key'
+	phase = phases.system_modification
+	predecessors = [AddEC2InitScripts, CreateAdminUser]
+	successors = [InstallInitScripts]
+
+	@classmethod
+	def run(cls, info):
+		from bootstrapvz.common.tools import log_check_call
+
+		log = logging.getLogger(__name__)
+
+		import stat
+		from shutil import copy
+		full_path = info.manifest.plugins['admin_user']['pubkey']
+		log.debug('Copying public key from {path}'.format(path=full_path))
+
+		if 'ec2-get-credentials' in info.initd['install']:
+			log.warn(
+				'You are using a static public key for the admin account.'
+				' This will conflict with the ec2 public key injection mechanisn.'
+				' The ec2-get-credentials startup script has therefore been disabled.')
+			del info.initd['install']['ec2-get-credentials']
+
+		username = info.manifest.plugins['admin_user']['username']
+
+		ssh_file = os.path.join('/home', username, '.ssh/authorized_keys')
+		rel_ssh_file = os.path.join(info.root, 'home', username, '.ssh/authorized_keys')
+
+		ssh_dir = os.path.dirname(ssh_file)
+		rel_ssh_dir = os.path.dirname(rel_ssh_file)
+		if not os.path.exists(rel_ssh_dir):
+			log.debug('Creating %s.' % rel_ssh_dir)
+			os.mkdir(rel_ssh_dir)
+
+		log.debug('setting %s mode 700' % rel_ssh_dir)
+		mode = (stat.S_IRUSR | stat.S_IWUSR | stat.S_IXUSR)
+		os.chmod(rel_ssh_dir, mode)
+
+		copy(full_path, rel_ssh_file)
+
+		mode = (stat.S_IRUSR | stat.S_IWUSR)
+		os.chmod(rel_ssh_file, mode)
+
+		log_check_call(['chroot', info.root, 'chown', '-R', username, ssh_dir])
+		return
+
+
+class AdminUserCredentialsEC2(Task):
+	description = 'Set up access credentials for the admin user using the EC2 credentials'
+	phase = phases.system_modification
+	predecessors = [InstallInitScripts, CreateAdminUser]
 
 	@classmethod
 	def run(cls, info):
 		from bootstrapvz.common.tools import sed_i
+		log = logging.getLogger(__name__)
+
 		getcreds_path = os.path.join(info.root, 'etc/init.d/ec2-get-credentials')
+		log.debug('Updating EC2 get credentials script.')
 		username = info.manifest.plugins['admin_user']['username']
-		sed_i(getcreds_path, 'username=\'root\'', 'username=\'{username}\''.format(username=username))
+		sed_i(getcreds_path, "username='root'",
+		      "username='{username}'".format(username=username))