move management into a daemon service running as root

* Created a new Python/flask-based management daemon.
* Moved the mail user management core code from tools/mail.py to the new daemon.
* tools/mail.py is a wrapper around the daemon and can be run as a non-root user.
* Adding a new initscript for the management daemon.
* Moving dns_update.sh to the management daemon, called via curl'ing the daemon's API.

This also now runs the DNS update after mail users and aliases are added/removed,
which sets up new domains' DNS as needed.

tools/mail.py

@@ -1,14 +1,15 @@
 #!/usr/bin/python3
 
-import sys, sqlite3, subprocess, shutil, os
+import sys, urllib.request, urllib.error
 
-# Load STORAGE_ROOT setting from /etc/mailinabox.conf.
-env = { }
-for line in open("/etc/mailinabox.conf"): env.setdefault(*line.strip().split("=", 1))
-
-# Connect to database.
-conn = sqlite3.connect(env["STORAGE_ROOT"] + "/mail/users.sqlite")
-c = conn.cursor()
+def mgmt(cmd, data=None):
+	req = urllib.request.Request('http://localhost:10222' + cmd, urllib.parse.urlencode(data).encode("utf8") if data else None)
+	try:
+		response = urllib.request.urlopen(req)
+	except urllib.error.HTTPError as e:
+		print(e.read().decode('utf8'))
+		sys.exit(1)
+	return response.read().decode('utf8')
 
 if len(sys.argv) < 2:
 	print("Usage: ")
@@ -24,9 +25,7 @@ if len(sys.argv) < 2:
 	print()
 
 elif sys.argv[1] == "user" and len(sys.argv) == 2:
-	c.execute('SELECT email FROM users')
-	for row in c.fetchall():
-		print(row[0])
+	print(mgmt("/mail/users"))
 
 elif sys.argv[1] == "user" and sys.argv[2] in ("add", "password"):
 	if len(sys.argv) < 5:
@@ -38,68 +37,23 @@ elif sys.argv[1] == "user" and sys.argv[2] in ("add", "password"):
 	else:
 		email, pw = sys.argv[3:5]
 
-	# hash the password
-	pw = subprocess.check_output(["/usr/bin/doveadm", "pw", "-s", "SHA512-CRYPT", "-p", pw]).strip()
-
 	if sys.argv[2] == "add":
-		try:
-			c.execute("INSERT INTO users (email, password) VALUES (?, ?)", (email, pw))
-		except sqlite3.IntegrityError:
-			print("User already exists.")
-			sys.exit(1)
-			
-		conn.commit() # write it before next step
-		
-		# Create the user's INBOX and Spam folders and subscribe them.
-
-		# Check if the mailboxes exist before creating them. When creating a user that had previously
-		# been deleted, the mailboxes will still exist because they are still on disk.
-		existing_mboxes = subprocess.check_output(["doveadm", "mailbox", "list", "-u", email, "-8"]).decode("utf8").split("\n")
-		
-		if "INBOX" not in existing_mboxes: subprocess.check_call(["doveadm", "mailbox", "create", "-u", email, "-s", "INBOX"])
-		if "Spam" not in existing_mboxes: subprocess.check_call(["doveadm", "mailbox", "create", "-u", email, "-s", "Spam"])
-		
-		# Create the user's sieve script to move spam into the Spam folder, and make it owned by mail.
-		maildirstat = os.stat(env["STORAGE_ROOT"] + "/mail/mailboxes")
-		(em_user, em_domain) = email.split("@", 1)
-		user_mail_dir = env["STORAGE_ROOT"] + ("/mail/mailboxes/%s/%s" % (em_domain, em_user))
-		if not os.path.exists(user_mail_dir):
-			os.makedirs(user_mail_dir)
-			os.chown(user_mail_dir, maildirstat.st_uid, maildirstat.st_gid)
-		shutil.copyfile("conf/dovecot_sieve.txt", user_mail_dir + "/.dovecot.sieve")
-		os.chown(user_mail_dir + "/.dovecot.sieve", maildirstat.st_uid, maildirstat.st_gid)
-		
+		print(mgmt("/mail/users/add", { "email": email, "password": pw }))
 	elif sys.argv[2] == "password":
-		c.execute("UPDATE users SET password=? WHERE email=?", (pw, email))
-		if c.rowcount != 1:
-			print("That's not a user.")
-			sys.exit(1)
+		print(mgmt("/mail/users/password", { "email": email, "password": pw }))
 
 elif sys.argv[1] == "user" and sys.argv[2] == "remove" and len(sys.argv) == 4:
-	c.execute("DELETE FROM users WHERE email=?", (sys.argv[3],))
-	if c.rowcount != 1:
-		print("That's not a user.")
-		sys.exit(1)
+	print(mgmt("/mail/users/remove", { "email": sys.argv[3] }))
 
 elif sys.argv[1] == "alias" and len(sys.argv) == 2:
-	c.execute('SELECT source, destination FROM aliases')
-	for row in c.fetchall():
-		print(row[0], "=>", row[1])
+	print(mgmt("/mail/aliases"))
 
 elif sys.argv[1] == "alias" and sys.argv[2] == "add" and len(sys.argv) == 5:
-	try:
-		c.execute("INSERT INTO aliases (source, destination) VALUES (?, ?)", (sys.argv[3], sys.argv[4]))
-	except sqlite3.IntegrityError:
-		print("Alias already exists.")
-		sys.exit(1)
+	print(mgmt("/mail/aliases/add", { "source": sys.argv[3], "destination": sys.argv[4] }))
 
 elif sys.argv[1] == "alias" and sys.argv[2] == "remove" and len(sys.argv) == 4:
-	c.execute("DELETE FROM aliases WHERE source=?", (sys.argv[3],))
-	if c.rowcount != 1:
-		print("That's not an alias.")
-		sys.exit(1)
+	print(mgmt("/mail/aliases/remove", { "source": sys.argv[3] }))
 
 else:
 	print("Invalid command-line arguments.")
 
-conn.commit()