+static int
+smtp_in_auth(auth_instance *au, uschar ** s, uschar ** ss)
+{
+const uschar *set_id = NULL;
+int rc, i;
+
+/* Run the checking code, passing the remainder of the command line as
+data. Initials the $auth<n> variables as empty. Initialize $0 empty and set
+it as the only set numerical variable. The authenticator may set $auth<n>
+and also set other numeric variables. The $auth<n> variables are preferred
+nowadays; the numerical variables remain for backwards compatibility.
+
+Afterwards, have a go at expanding the set_id string, even if
+authentication failed - for bad passwords it can be useful to log the
+userid. On success, require set_id to expand and exist, and put it in
+authenticated_id. Save this in permanent store, as the working store gets
+reset at HELO, RSET, etc. */
+
+for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL;
+expand_nmax = 0;
+expand_nlength[0] = 0; /* $0 contains nothing */
+
+rc = (au->info->servercode)(au, smtp_cmd_data);
+if (au->set_id) set_id = expand_string(au->set_id);
+expand_nmax = -1; /* Reset numeric variables */
+for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL; /* Reset $auth<n> */
+
+/* The value of authenticated_id is stored in the spool file and printed in
+log lines. It must not contain binary zeros or newline characters. In
+normal use, it never will, but when playing around or testing, this error
+can (did) happen. To guard against this, ensure that the id contains only
+printing characters. */
+
+if (set_id) set_id = string_printing(set_id);
+
+/* For the non-OK cases, set up additional logging data if set_id
+is not empty. */
+
+if (rc != OK)
+ set_id = set_id && *set_id
+ ? string_sprintf(" (set_id=%s)", set_id) : US"";
+
+/* Switch on the result */
+
+switch(rc)
+ {
+ case OK:
+ if (!au->set_id || set_id) /* Complete success */
+ {
+ if (set_id) authenticated_id = string_copy_malloc(set_id);
+ sender_host_authenticated = au->name;
+ authentication_failed = FALSE;
+ authenticated_fail_id = NULL; /* Impossible to already be set? */
+
+ received_protocol =
+ (sender_host_address ? protocols : protocols_local)
+ [pextend + pauthed + (tls_in.active >= 0 ? pcrpted:0)];
+ *s = *ss = US"235 Authentication succeeded";
+ authenticated_by = au;
+ break;
+ }
+
+ /* Authentication succeeded, but we failed to expand the set_id string.
+ Treat this as a temporary error. */
+
+ auth_defer_msg = expand_string_message;
+ /* Fall through */
+
+ case DEFER:
+ if (set_id) authenticated_fail_id = string_copy_malloc(set_id);
+ *s = string_sprintf("435 Unable to authenticate at present%s",
+ auth_defer_user_msg);
+ *ss = string_sprintf("435 Unable to authenticate at present%s: %s",
+ set_id, auth_defer_msg);
+ break;
+
+ case BAD64:
+ *s = *ss = US"501 Invalid base64 data";
+ break;
+
+ case CANCELLED:
+ *s = *ss = US"501 Authentication cancelled";
+ break;
+
+ case UNEXPECTED:
+ *s = *ss = US"553 Initial data not expected";
+ break;
+
+ case FAIL:
+ if (set_id) authenticated_fail_id = string_copy_malloc(set_id);
+ *s = US"535 Incorrect authentication data";
+ *ss = string_sprintf("535 Incorrect authentication data%s", set_id);
+ break;
+
+ default:
+ if (set_id) authenticated_fail_id = string_copy_malloc(set_id);
+ *s = US"435 Internal error";
+ *ss = string_sprintf("435 Internal error%s: return %d from authentication "
+ "check", set_id, rc);
+ break;
+ }
+
+return rc;
+}
+
+
+
+
+
+static int
+qualify_recipient(uschar ** recipient, uschar * smtp_cmd_data, uschar * tag)
+{
+int rd;
+if (allow_unqualified_recipient || strcmpic(*recipient, US"postmaster") == 0)
+ {
+ DEBUG(D_receive) debug_printf("unqualified address %s accepted\n",
+ *recipient);
+ rd = Ustrlen(recipient) + 1;
+ *recipient = rewrite_address_qualify(*recipient, TRUE);
+ return rd;
+ }
+smtp_printf("501 %s: recipient address must contain a domain\r\n",
+ smtp_cmd_data);
+log_write(L_smtp_syntax_error,
+ LOG_MAIN|LOG_REJECT, "unqualified %s rejected: <%s> %s%s",
+ tag, *recipient, host_and_ident(TRUE), host_lookup_msg);
+return 0;
+}
+
+
+
+
+static void
+smtp_quit_handler(uschar ** user_msgp, uschar ** log_msgp)
+{
+HAD(SCH_QUIT);
+incomplete_transaction_log(US"QUIT");
+if (acl_smtp_quit != NULL)
+ {
+ int rc = acl_check(ACL_WHERE_QUIT, NULL, acl_smtp_quit, user_msgp, log_msgp);
+ if (rc == ERROR)
+ log_write(0, LOG_MAIN|LOG_PANIC, "ACL for QUIT returned ERROR: %s",
+ *log_msgp);
+ }
+if (*user_msgp)
+ smtp_respond(US"221", 3, TRUE, *user_msgp);
+else
+ smtp_printf("221 %s closing connection\r\n", smtp_active_hostname);
+
+#ifdef SUPPORT_TLS
+tls_close(TRUE, TRUE);
+#endif
+
+log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT",
+ smtp_get_connection_info());
+}
+
+
+static void
+smtp_rset_handler(void)
+{
+HAD(SCH_RSET);
+incomplete_transaction_log(US"RSET");
+smtp_printf("250 Reset OK\r\n");
+cmd_list[CMD_LIST_RSET].is_mail_cmd = FALSE;
+}
+
+
+