From 3d96f0fdfa6650abc2d598ca78925d0ed54b48ac Mon Sep 17 00:00:00 2001
From: holger krekel <holger@merlinux.eu>
Date: Sat, 6 Jul 2024 03:19:57 +0200
Subject: [PATCH] Support iterating over all users with doveadm commands (#344)

---
 CHANGELOG.md                                  |  3 +++
 chatmaild/src/chatmaild/doveauth.py           | 18 +++++++++++++++
 .../src/chatmaild/tests/test_doveauth.py      | 23 +++++++++++++++++++
 cmdeploy/src/cmdeploy/dovecot/auth.conf       |  4 +++-
 4 files changed, 47 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 90378ad4..4191e3a0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,9 @@
 
 ## untagged
 
+- Support iterating over all users with doveadm commands 
+  ([#344](https://github.com/deltachat/chatmail/pull/344))
+
 - Test and fix for attempts to create inadmissible accounts 
   ([#333](https://github.com/deltachat/chatmail/pull/321))
 
diff --git a/chatmaild/src/chatmaild/doveauth.py b/chatmaild/src/chatmaild/doveauth.py
index 52246beb..700fa73e 100644
--- a/chatmaild/src/chatmaild/doveauth.py
+++ b/chatmaild/src/chatmaild/doveauth.py
@@ -129,6 +129,15 @@ def lookup_passdb(db, config: Config, user, cleartext_password):
         )
 
 
+def iter_userdb(db, config: Config) -> list:
+    """Get a list of all user addresses."""
+    with db.read_connection() as conn:
+        rows = conn.execute(
+            "SELECT addr from users",
+        ).fetchall()
+    return [x[0] for x in rows]
+
+
 def split_and_unescape(s):
     """Split strings using double quote as a separator and backslash as escape character
     into parts."""
@@ -192,6 +201,15 @@ def handle_dovecot_request(msg, db, config: Config):
                     reply_command = "N"
         json_res = json.dumps(res) if res else ""
         return f"{reply_command}{json_res}\n"
+    elif short_command == "I":  # ITERATE
+        # example: I0\t0\tshared/userdb/
+        parts = msg[1:].split("\t")
+        if parts[2] == "shared/userdb/":
+            result = "".join(
+                f"Oshared/userdb/{user}\t\n" for user in iter_userdb(db, config)
+            )
+            return f"{result}\n"
+
     raise UnknownCommand(msg)
 
 
diff --git a/chatmaild/src/chatmaild/tests/test_doveauth.py b/chatmaild/src/chatmaild/tests/test_doveauth.py
index 99bf9575..2b27942e 100644
--- a/chatmaild/src/chatmaild/tests/test_doveauth.py
+++ b/chatmaild/src/chatmaild/tests/test_doveauth.py
@@ -12,6 +12,7 @@ from chatmaild.doveauth import (
     handle_dovecot_protocol,
     handle_dovecot_request,
     is_allowed_to_create,
+    iter_userdb,
     lookup_passdb,
 )
 from chatmaild.newemail import create_newemail_dict
@@ -27,6 +28,16 @@ def test_basic(db, example_config):
     assert data == data2
 
 
+def test_iterate_addresses(db, example_config):
+    addresses = []
+
+    for i in range(10):
+        addresses.append(f"asdf1234{i}@chat.example.org")
+        lookup_passdb(db, example_config, addresses[-1], "q9mr3faue")
+    res = iter_userdb(db, example_config)
+    assert res == addresses
+
+
 def test_invalid_username_length(example_config):
     config = example_config
     config.username_min_length = 6
@@ -108,6 +119,18 @@ def test_handle_dovecot_protocol(db, example_config):
     assert wfile.getvalue() == b"N\n"
 
 
+def test_handle_dovecot_protocol_iterate(db, gencreds, example_config):
+    lookup_passdb(db, example_config, "asdf00000@chat.example.org", "q9mr3faue")
+    lookup_passdb(db, example_config, "asdf11111@chat.example.org", "q9mr3faue")
+    rfile = io.BytesIO(b"H3\t2\t0\t\tauth\nI0\t0\tshared/userdb/")
+    wfile = io.BytesIO()
+    handle_dovecot_protocol(rfile, wfile, db, example_config)
+    lines = wfile.getvalue().decode("ascii").split("\n")
+    assert lines[0] == "Oshared/userdb/asdf00000@chat.example.org\t"
+    assert lines[1] == "Oshared/userdb/asdf11111@chat.example.org\t"
+    assert not lines[2]
+
+
 def test_50_concurrent_lookups_different_accounts(db, gencreds, example_config):
     num_threads = 50
     req_per_thread = 5
diff --git a/cmdeploy/src/cmdeploy/dovecot/auth.conf b/cmdeploy/src/cmdeploy/dovecot/auth.conf
index 4abcdfb9..cc9758d4 100644
--- a/cmdeploy/src/cmdeploy/dovecot/auth.conf
+++ b/cmdeploy/src/cmdeploy/dovecot/auth.conf
@@ -1,5 +1,7 @@
 uri = proxy:/run/doveauth/doveauth.socket:auth
-iterate_disable = yes
+iterate_disable = no
+iterate_prefix = userdb/
+
 default_pass_scheme = plain
 # %E escapes characters " (double quote), ' (single quote) and \ (backslash) with \ (backslash).
 # See <https://doc.dovecot.org/configuration_manual/config_file/config_variables/#modifiers>