From 9222388d61d94edcc1176d18bd708a63dddc63a3 Mon Sep 17 00:00:00 2001
From: Timo Sirainen <timo.sirainen@dovecot.fi>
Date: Fri, 8 Sep 2017 11:02:07 +0300
Subject: [PATCH] lmtp proxy: Avoid DNS lookup for "host" if passdb also
 returns "hostip"

---
 src/lmtp/commands.c   | 15 ++++++++++++---
 src/lmtp/lmtp-proxy.c |  5 ++++-
 src/lmtp/lmtp-proxy.h |  1 +
 3 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/src/lmtp/commands.c b/src/lmtp/commands.c
index 2496c1f8a9..55e7f0f7a2 100644
--- a/src/lmtp/commands.c
+++ b/src/lmtp/commands.c
@@ -250,7 +250,12 @@ client_proxy_rcpt_parse_fields(struct lmtp_proxy_rcpt_settings *set,
 			proxying = TRUE;
 		else if (strcmp(key, "host") == 0)
 			set->host = value;
-		else if (strcmp(key, "port") == 0) {
+		else if (strcmp(key, "hostip") == 0) {
+			if (net_addr2ip(value, &set->hostip) < 0) {
+				i_error("proxy: Invalid hostip %s", value);
+				return FALSE;
+			}
+		} else if (strcmp(key, "port") == 0) {
 			if (net_str2port(value, &set->port) < 0) {
 				i_error("proxy: Invalid port number %s", value);
 				return FALSE;
@@ -297,8 +302,12 @@ client_proxy_is_ourself(const struct client *client,
 	if (set->port != client->local_port)
 		return FALSE;
 
-	if (net_addr2ip(set->host, &ip) < 0)
-		return FALSE;
+	if (set->hostip.family != 0)
+		ip = set->hostip;
+	else {
+		if (net_addr2ip(set->host, &ip) < 0)
+			return FALSE;
+	}
 	if (!net_ip_compare(&ip, &client->local_ip))
 		return FALSE;
 	return TRUE;
diff --git a/src/lmtp/lmtp-proxy.c b/src/lmtp/lmtp-proxy.c
index 1293d25c0e..f717c06874 100644
--- a/src/lmtp/lmtp-proxy.c
+++ b/src/lmtp/lmtp-proxy.c
@@ -146,7 +146,10 @@ lmtp_proxy_get_connection(struct lmtp_proxy *proxy,
 
 	conn = p_new(proxy->pool, struct lmtp_proxy_connection, 1);
 	conn->proxy = proxy;
-	conn->set.host = p_strdup(proxy->pool, set->host);
+	if (set->hostip.family == 0)
+		conn->set.host = p_strdup(proxy->pool, set->host);
+	else
+		conn->set.host = p_strdup(proxy->pool, net_ip2addr(&set->hostip));
 	conn->set.port = set->port;
 	conn->set.timeout_msecs = set->timeout_msecs;
 	array_append(&proxy->connections, &conn, 1);
diff --git a/src/lmtp/lmtp-proxy.h b/src/lmtp/lmtp-proxy.h
index 1ad0b61ae4..d5c80e8a1c 100644
--- a/src/lmtp/lmtp-proxy.h
+++ b/src/lmtp/lmtp-proxy.h
@@ -19,6 +19,7 @@ struct lmtp_proxy_settings {
 
 struct lmtp_proxy_rcpt_settings {
 	const char *host;
+	struct ip_addr hostip;
 	in_port_t port;
 	unsigned int timeout_msecs;
 	enum lmtp_client_protocol protocol;
-- 
2.47.3