fix: Avoid alias being used as regex during dovecot dummy account userdb detection (#4222)

Applies alternative approach previously suggested by @polarathene and adds test cases to prevent future regressions

CHANGELOG.md

@@ -46,6 +46,7 @@ All notable changes to this project will be documented in this file. The format
 - **Dovecot:**
   - Update logwatch `ignore.conf` to exclude Xapian messages about pending documents ([#4060](https://github.com/docker-mailserver/docker-mailserver/pull/4060))
   - `dovecot-fts-xapian` plugin was updated to `1.7.13`, fixing a regression with indexing ([#4095](https://github.com/docker-mailserver/docker-mailserver/pull/4095))
+  - The Dovecot Quota support "dummy account" workaround no longer treats the alias as a regex when checking the Dovecot UserDB ([#4222](https://github.com/docker-mailserver/docker-mailserver/pull/4222))
 - **LDAP:**
   - A previous compatibility fix for OAuth2 in v13.3.1 had not applied the actual LDAP config changes. This has been corrected ([#4175](https://github.com/docker-mailserver/docker-mailserver/pull/4175))
 - **Internal:**

target/scripts/helpers/accounts.sh

@@ -135,7 +135,8 @@ function _create_dovecot_alias_dummy_accounts() {
       fi
 
       DOVECOT_USERDB_LINE="${ALIAS}:${REAL_ACC[1]}:${DMS_VMAIL_UID}:${DMS_VMAIL_GID}::/var/mail/${REAL_DOMAINNAME}/${REAL_USERNAME}/home::${REAL_ACC[2]:-}"
-      if grep -qi "^${ALIAS}:" "${DOVECOT_USERDB_FILE}"; then
+      # Match a full line with `-xF` to avoid regex patterns introducing false positives matching `ALIAS`:
+      if grep -qixF "${DOVECOT_USERDB_LINE}" "${DOVECOT_USERDB_FILE}"; then
         _log 'warn' "Alias '${ALIAS}' will not be added to '${DOVECOT_USERDB_FILE}' twice"
       else
         echo "${DOVECOT_USERDB_LINE}" >>"${DOVECOT_USERDB_FILE}"

test/config/postfix-virtual.cf

@@ -3,3 +3,13 @@ alias1@localhost.localdomain user1@localhost.localdomain
     # this is also a test comment, :O
 alias2@localhost.localdomain external1@otherdomain.tld
 @localdomain2.com user1@localhost.localdomain
+
+## Dovecot "dummy accounts" for quota support (handled in `helpers/accounts.sh`)
+# Do not filter alias by substring condition (longer prefix must be before substring alias):
+# https://github.com/docker-mailserver/docker-mailserver/issues/2639
+prefixtest@localhost.localdomain user2@otherdomain.tld
+test@localhost.localdomain user2@otherdomain.tld
+# Do not filter alias when input be treated as regex tokens (eg `.`):
+# https://github.com/docker-mailserver/docker-mailserver/issues/4170
+first-name@localhost.localdomain user2@otherdomain.tld
+first.name@localhost.localdomain user2@otherdomain.tld

test/tests/parallel/set3/mta/account_management.bats

@@ -29,7 +29,12 @@ function teardown_file() { _default_teardown ; }
   assert_line --index 5 'alias1@localhost.localdomain'
   # TODO: Probably not intentional?:
   assert_line --index 6 '@localdomain2.com'
-  _should_output_number_of_lines 7
+  # Dovecot "dummy accounts" for quota support, see `test/config/postfix-virtual.cf` for more context
+  assert_line --index 7 'prefixtest@localhost.localdomain'
+  assert_line --index 8 'test@localhost.localdomain'
+  assert_line --index 9 'first-name@localhost.localdomain'
+  assert_line --index 10 'first.name@localhost.localdomain'
+  _should_output_number_of_lines 11
 
   # Relevant log output from scripts/helpers/accounts.sh:_create_dovecot_alias_dummy_accounts():
   # [  DEBUG  ]  Adding alias 'alias1@localhost.localdomain' for user 'user1@localhost.localdomain' to Dovecot's userdb
@@ -37,6 +42,19 @@ function teardown_file() { _default_teardown ; }
   # [  DEBUG  ]  Adding alias '@localdomain2.com' for user 'user1@localhost.localdomain' to Dovecot's userdb
 }
 
+# Dovecot "dummy accounts" for quota support, see `test/config/postfix-virtual.cf` for more context
+@test "should create all dovecot dummy accounts" {
+  run docker logs "${CONTAINER_NAME}"
+  assert_success
+  assert_line --partial "Adding alias 'prefixtest@localhost.localdomain' for user 'user2@otherdomain.tld' to Dovecot's userdb"
+  assert_line --partial "Adding alias 'test@localhost.localdomain' for user 'user2@otherdomain.tld' to Dovecot's userdb"
+  refute_line --partial "Alias 'test@localhost.localdomain' will not be added to '/etc/dovecot/userdb' twice"
+
+  assert_line --partial "Adding alias 'first-name@localhost.localdomain' for user 'user2@otherdomain.tld' to Dovecot's userdb"
+  assert_line --partial "Adding alias 'first.name@localhost.localdomain' for user 'user2@otherdomain.tld' to Dovecot's userdb"
+  refute_line --partial "Alias 'first.name@localhost.localdomain' will not be added to '/etc/dovecot/userdb' twice"
+}
+
 @test "should have created maildir for 'user1@localhost.localdomain'" {
   _run_in_container_bash '[[ -d /var/mail/localhost.localdomain/user1 ]]'
   assert_success