More work on the authentication infrastructure

src/calibre/srv/handler.py

@@ -14,6 +14,7 @@ from threading import Lock
 
 from calibre.db.cache import Cache
 from calibre.db.legacy import create_backend, LibraryDatabase
+from calibre.srv.auth import AuthController
 from calibre.srv.routes import Router
 from calibre.srv.users import UserManager
 from calibre.utils.date import utcnow
@@ -86,7 +87,7 @@ class Context(object):
         self.library_broker = LibraryBroker(libraries)
         self.testing = testing
         self.lock = Lock()
-        self.user_manager = UserManager()
+        self.user_manager = UserManager(opts.userdb)
 
     def init_session(self, endpoint, data):
         pass
@@ -144,7 +145,13 @@ class Context(object):
 class Handler(object):
 
     def __init__(self, libraries, opts, testing=False):
-        self.router = Router(ctx=Context(libraries, opts, testing=testing), url_prefix=opts.url_prefix)
+        ctx = Context(libraries, opts, testing=testing)
+        self.auth_controller = None
+        if opts.auth:
+            has_ssl = opts.ssl_certfile is not None and opts.ssl_keyfile is not None
+            prefer_basic_auth = {'auto':has_ssl, 'basic':True}.get(opts.auth_mode, 'digest')
+            self.auth_controller = AuthController(user_credentials=ctx.user_manager, prefer_basic_auth=prefer_basic_auth)
+        self.router = Router(ctx=ctx, url_prefix=opts.url_prefix, auth_controller=self.auth_controller)
         for module in ('content', 'ajax', 'code'):
             module = import_module('calibre.srv.' + module)
             self.router.load_routes(vars(module).itervalues())
@@ -154,6 +161,8 @@ class Handler(object):
 
     def set_log(self, log):
         self.router.ctx.log = log
+        if self.auth_controller is not None:
+            self.auth_controller.log = log
 
     def close(self):
         self.router.ctx.library_broker.close()

src/calibre/srv/opts.py

@@ -92,6 +92,22 @@ raw_options = (
     'max_log_size', 20,
     'The maximum size of log files, generated by the server. When the log becomes larger'
     ' than this size, it is automatically rotated.',
+
+    'Enable/disable password based authentication to access the server',
+    'auth', False,
+    'By default, the server is unrestricted, allowing anyone to access it. You can'
+    ' restrict access to predefined users with this option.',
+
+    'Path to user database',
+    'userdb', None,
+    'Path to a file in which to store the user and password information. By default a'
+    ' file in the calibre configuration directory is used.',
+
+    'Choose the type of authentication used',
+    'auth_mode', Choices('auto', 'basic', 'digest'),
+    'Set the HTTP authentication mode used by the server. Set to "basic" is you are'
+    ' putting this server behind an SSL proxy. Otherwise, leave it as "auto", which'
+    ' will use "basic" if SSL is configured otherwise it will use "digest".',
 )
 assert len(raw_options) % 4 == 0
 
@@ -105,7 +121,7 @@ def grouper(n, iterable, fillvalue=None):
 for shortdoc, name, default, doc in grouper(4, raw_options):
     choices = None
     if isinstance(default, Choices):
-        choices = default
+        choices = sorted(default)
         default = default.default
     options.append(Option(name, default, doc, shortdoc, choices))
 options = OrderedDict([(o.name, o) for o in sorted(options, key=attrgetter('name'))])

src/calibre/srv/users.py

@@ -5,62 +5,71 @@
 from __future__ import (unicode_literals, division, absolute_import,
                         print_function)
 import os, json
+from threading import Lock
 
 import apsw
 
 from calibre.constants import config_dir
 from calibre.utils.config import to_json, from_json
 
+
 class UserManager(object):
 
+    lock = Lock()
+
     @property
     def conn(self):
         if self._conn is None:
             self._conn = apsw.Connection(self.path)
-            c = self._conn.cursor()
-            uv = next(c.execute('PRAGMA foreign_keys = ON; PRAGMA user_version'))[0]
-            if uv == 0:
-                c.execute('''
-CREATE TABLE users (
-    id INTEGER PRIMARY KEY,
-    name TEXT NOT NULL,
-    salt TEXT NOT NULL,
-    hashed_pw TEXT NOT NULL,
-    hash_type TEXT NOT NULL,
-    creation_date INTEGER NOT NULL,
-    UNIQUE(name)
-);
+            with self._conn:
+                c = self._conn.cursor()
+                uv = next(c.execute('PRAGMA user_version'))[0]
+                if uv == 0:
+                    # We have to store the unhashed password, since the digest
+                    # auth scheme requires it.
+                    # timestamp stores the ISO 8601 creation timestamp in UTC.
+                    c.execute('''
+                    CREATE TABLE users (
+                        id INTEGER PRIMARY KEY,
+                        name TEXT NOT NULL,
+                        pw TEXT NOT NULL,
+                        timestamp TEXT DEFAULT CURRENT_TIMESTAMP,
+                        session_data TEXT NOT NULL DEFAULT "{}",
+                        restriction TEXT NOT NULL DEFAULT "",
+                        misc_data TEXT NOT NULL DEFAULT "{}",
+                        UNIQUE(name)
+                    );
 
-CREATE TABLE session_data (
-    id INTEGER PRIMARY KEY,
-    user INTEGER NOT NULL,
-    data TEXT NOT NULL,
-    UNIQUE(user),
-    FOREIGN KEY user REFERENCES users.id
-);
+                    PRAGMA user_version=1;
+                    ''')
+                c.close()
 
-PRAGMA user_version=1;
-''')
-            c.close()
-
-    def __init__(self):
-        self.path = os.path.join(config_dir, 'server-users.sqlite')
+    def __init__(self, path=None):
+        self.path = os.path.join(config_dir, 'server-users.sqlite') if path is None else path
         self._conn = None
 
     def get_session_data(self, username):
-        for data, in self.conn.cursor().execute(
-                'SELECT data FROM session_data INNER JOIN users ON (session_data.user = users.id) WHERE users.name=?', (username,)):
-            try:
-                return json.loads(data, object_hook=from_json)
-            except Exception:
-                pass
-        return {}
+        with self.lock:
+            for data, in self.conn.cursor().execute(
+                    'SELECT data FROM users WHERE name=?', (username,)):
+                try:
+                    return json.loads(data, object_hook=from_json)
+                except Exception:
+                    break
+            return {}
 
     def set_session_data(self, username, data):
-        conn = self.conn
-        c = conn.cursor()
-        for user_id, in c.execute('SELECT id FROM users WHERE name=?', (username,)):
+        with self.lock:
+            conn = self.conn
+            c = conn.cursor()
             data = json.dumps(data, ensure_ascii=False, default=to_json)
-            c.execute('UPDATE session_data SET data=? WHERE user=?', (data, user_id))
-            if not conn.changes():
-                c.execute('INSERT INTO session_data (data,user) VALUES (?,?)', (data, user_id))
+            if isinstance(data, bytes):
+                data = data.decode('utf-8')
+            c.execute('UPDATE users SET data=? WHERE name=?', (data, username))
+
+    def get(self, username):
+        ' Get password for user, or None if user does not exist '
+        with self.lock:
+            for pw, in self.conn.cursor().execute(
+                    'SELECT pw FROM users WHERE name=?', (username,)):
+                return pw

src/pyj/ajax.pyj

@@ -46,3 +46,9 @@ def ajax(path, on_complete, on_progress=None, bypass_cache=True, method='GET', q
     xhr.open(method, path)
     return xhr
 
+# TODO: Implement AJAX based switch user by:
+# 1) POST to a logout URL with an incorrect username and password
+# 2) Have the server accept that incorrect username/password
+# 3) Navigate to / which should cause the browser to re-prompt for username and password
+# (only problem is login dialog will likely pre-show the wrong username) To workaround that,
+# You can consider using a dedicated ajax based login form, see http://www.peej.co.uk/articles/http-auth-with-html-forms.html)