From 089fb2fb2d9e2a3473aa6fac91681ca8ddfffff3 Mon Sep 17 00:00:00 2001
From: Andre Noll <maan@tuebingen.mpg.de>
Date: Thu, 16 Nov 2017 03:35:01 +0100
Subject: [PATCH] sender: Deplete ACLs on exit.

This teaches the dccp and the http sender to empty their access control
lists during shutdown, avoiding some (harmless) memory leaks at exit.
---
 dccp_send.c   |  8 +++++++-
 http_send.c   |  8 +++++++-
 send.h        |  1 +
 send_common.c | 16 ++++++++++++++++
 4 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/dccp_send.c b/dccp_send.c
index bd6c0257..0b454e79 100644
--- a/dccp_send.c
+++ b/dccp_send.c
@@ -80,6 +80,12 @@ static void dccp_shutdown_clients(void)
 		dccp_shutdown_client(sc);
 }
 
+static void dccp_shutdown(void)
+{
+	dccp_shutdown_clients();
+	generic_acl_deplete(&dss->acl);
+}
+
 /** * Obtain current MPS according to RFC 4340, sec. 14. */
 static int dccp_init_fec(struct sender_client *sc)
 {
@@ -238,7 +244,7 @@ static void dccp_send_init(void)
 const struct sender dccp_sender = {
 	.name = "dccp",
 	.init = dccp_send_init,
-	.shutdown = dccp_shutdown_clients,
+	.shutdown = dccp_shutdown,
 	.pre_select = dccp_pre_select,
 	.post_select = dccp_post_select,
 	.shutdown_clients = dccp_shutdown_clients,
diff --git a/http_send.c b/http_send.c
index fb9fd9b3..9a35fc99 100644
--- a/http_send.c
+++ b/http_send.c
@@ -75,6 +75,12 @@ static void http_shutdown_clients(void)
 	shutdown_clients(hss);
 }
 
+static void http_shutdown(void)
+{
+	http_shutdown_clients();
+	generic_acl_deplete(&hss->acl);
+}
+
 static int queue_chunk_or_shutdown(struct sender_client *sc,
 		struct sender_status *ss, const char *buf, size_t num_bytes)
 {
@@ -264,7 +270,7 @@ static void http_send_init(void)
 const struct sender http_sender = {
 	.name = "http",
 	.init = http_send_init,
-	.shutdown = http_shutdown_clients,
+	.shutdown = http_shutdown,
 	.pre_select = http_pre_select,
 	.post_select = http_post_select,
 	.send = http_send,
diff --git a/send.h b/send.h
index bca03b20..212fb4a1 100644
--- a/send.h
+++ b/send.h
@@ -190,6 +190,7 @@ void generic_com_allow(struct sender_command_data *scd,
 		struct sender_status *ss);
 void generic_com_deny(struct sender_command_data *scd,
 		struct sender_status *ss);
+void generic_acl_deplete(struct list_head *acl);
 int generic_com_on(struct sender_status *ss, unsigned protocol);
 void generic_com_off(struct sender_status *ss);
 char *generic_sender_help(void);
diff --git a/send_common.c b/send_common.c
index 2088c8b4..3e8a7c0d 100644
--- a/send_common.c
+++ b/send_common.c
@@ -218,6 +218,22 @@ void generic_com_allow(struct sender_command_data *scd,
 	acl_allow(scd->host, scd->netmask, &ss->acl, ss->default_deny);
 }
 
+/**
+ * Empty the access control list of a sender.
+ *
+ * \param acl The access control list of the sender.
+ *
+ * This is called from the ->shutdown methods of the http and the dccp sender.
+ */
+void generic_acl_deplete(struct list_head *acl)
+{
+	/*
+	 * Since default_deny is false, the ACL is considered a blacklist. A
+	 * netmask of zero matches any IP address, so this call empties the ACL.
+	 */
+	acl_allow("0.0.0.0", 0 /* netmask */, acl, 0 /* default_deny */);
+}
+
 /**
  * Deny connections from the given range of IP addresses.
  *
-- 
2.39.5