From: Aki Tuomi <aki.tuomi@open-xchange.com>
Date: Mon, 20 Apr 2020 11:57:07 +0000 (+0300)
Subject: lib-smtp: smtp-client-connection - Try all IPs when connecting to remote host
X-Git-Tag: 2.3.11.2~180
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=666a8303e4f34eb5d7e1f4452f307be5098c851e;p=thirdparty%2Fdovecot%2Fcore.git

lib-smtp: smtp-client-connection - Try all IPs when connecting to remote host
---

diff --git a/src/lib-smtp/smtp-client-connection.c b/src/lib-smtp/smtp-client-connection.c
index a8782b3bb2..a49e9376d9 100644
--- a/src/lib-smtp/smtp-client-connection.c
+++ b/src/lib-smtp/smtp-client-connection.c
@@ -39,6 +39,10 @@ static void
 smtp_client_connection_established(struct smtp_client_connection *conn);
 static void
 smtp_client_connection_start_transaction(struct smtp_client_connection *conn);
+static void
+smtp_client_connection_connect_next_ip(struct smtp_client_connection *conn);
+static bool
+smtp_client_connection_last_ip(struct smtp_client_connection *conn);
 
 /*
  * Capabilities
@@ -281,6 +285,14 @@ void smtp_client_connection_fail(struct smtp_client_connection *conn,
 	struct smtp_reply reply;
 	const char *text_lines[] = {error, NULL};
 
+	if (status == SMTP_CLIENT_COMMAND_ERROR_CONNECT_FAILED &&
+	    !smtp_client_connection_last_ip(conn)) {
+		i_assert(conn->to_connect == NULL);
+		conn->to_connect = timeout_add_short(0, smtp_client_connection_connect_next_ip,
+						     conn);
+		return;
+	}
+
 	i_zero(&reply);
 	reply.status = status;
 	reply.text_lines = text_lines;
@@ -1488,6 +1500,13 @@ smtp_client_connection_do_connect(struct smtp_client_connection *conn)
 	}
 }
 
+static bool
+smtp_client_connection_last_ip(struct smtp_client_connection *conn)
+{
+	i_assert(conn->prev_connect_idx < conn->ips_count);
+	return (conn->prev_connect_idx + 1) % conn->ips_count == 0;
+}
+
 static void
 smtp_client_connection_connect_next_ip(struct smtp_client_connection *conn)
 {