From 1c3030c8cee48ab52d988e8be4914a7804a5fbec Mon Sep 17 00:00:00 2001
From: gaoxingwang <gaoxingwang@huawei.com>
Date: Tue, 7 Jun 2022 10:43:13 +0800
Subject: [PATCH 2/2] add IPV6_DROP_MEMBERSHIP to clean up resources when
 reload or restart radvd

Reference:https://github.com/radvd-project/radvd/commit/1c3030c8cee48ab52d988e8be4914a7804a5fbec
Conflict:NA

---
 device-bsd44.c |  1 +
 device-linux.c | 16 ++++++++++++++++
 interface.c    |  6 ++++++
 radvd.c        | 11 +++++++++++
 radvd.h        |  2 ++
 5 files changed, 36 insertions(+)

diff --git a/device-bsd44.c b/device-bsd44.c
index fe411ba..68c1df1 100644
--- a/device-bsd44.c
+++ b/device-bsd44.c
@@ -127,6 +127,7 @@ ret:
 }
 
 int setup_allrouters_membership(int sock, struct Interface *iface) { return 0; }
+int cleanup_allrouters_membership(int sock, struct Interface *iface) { return 0; }
 
 int set_interface_linkmtu(const char *iface, uint32_t mtu)
 {
diff --git a/device-linux.c b/device-linux.c
index 5874e5c..019c126 100644
--- a/device-linux.c
+++ b/device-linux.c
@@ -185,6 +185,22 @@ int setup_allrouters_membership(int sock, struct Interface *iface)
 	return 0;
 }
 
+int cleanup_allrouters_membership(int sock, struct Interface *iface)
+{
+	struct ipv6_mreq mreq;
+
+	memset(&mreq, 0, sizeof(mreq));
+	mreq.ipv6mr_interface = iface->props.if_index;
+
+	/* ipv6-allrouters: ff02::2 */
+	mreq.ipv6mr_multiaddr.s6_addr32[0] = htonl(0xFF020000);
+	mreq.ipv6mr_multiaddr.s6_addr32[3] = htonl(0x2);
+
+	setsockopt(sock, SOL_IPV6, IPV6_DROP_MEMBERSHIP, &mreq, sizeof(mreq));
+
+	return 0;
+}
+
 uint32_t get_interface_linkmtu(const char *iface)
 {
 	int value;
diff --git a/interface.c b/interface.c
index f5f9a54..222d1aa 100644
--- a/interface.c
+++ b/interface.c
@@ -109,6 +109,12 @@ int setup_iface(int sock, struct Interface *iface)
 	return 0;
 }
 
+int cleanup_iface(int sock, struct Interface *iface)
+{
+	/* leave the allrouters multicast group */
+	cleanup_allrouters_membership(sock, iface);
+	return 0;
+}
 void prefix_init_defaults(struct AdvPrefix *prefix)
 {
 	memset(prefix, 0, sizeof(struct AdvPrefix));
diff --git a/radvd.c b/radvd.c
index 22255b1..3bd3a06 100644
--- a/radvd.c
+++ b/radvd.c
@@ -93,6 +93,7 @@ static void reset_prefix_lifetimes(struct Interface *ifaces);
 static void reset_prefix_lifetimes_foo(struct Interface *iface, void *data);
 static void setup_iface_foo(struct Interface *iface, void *data);
 static void setup_ifaces(int sock, struct Interface *ifaces);
+static void cleanup_ifaces(int sock, struct Interface *ifaces);
 static void sighup_handler(int sig);
 static void sigint_handler(int sig);
 static void sigterm_handler(int sig);
@@ -435,6 +436,8 @@ int main(int argc, char *argv[])
 	setup_ifaces(sock, ifaces);
 	ifaces = main_loop(sock, ifaces, conf_path);
 	stop_adverts(sock, ifaces);
+	cleanup_ifaces(sock, ifaces);
+	close(sock);
 
 	flog(LOG_INFO, "removing %s", daemon_pid_file_ident);
 	unlink(daemon_pid_file_ident);
@@ -778,10 +781,18 @@ static void setup_iface_foo(struct Interface *iface, void *data)
 	kickoff_adverts(sock, iface);
 }
 
+static void cleanup_iface_foo(struct Interface *iface, void *data)
+{
+	int sock = *(int *)data;
+	cleanup_iface(sock, iface);
+}
+
 static void setup_ifaces(int sock, struct Interface *ifaces) { for_each_iface(ifaces, setup_iface_foo, &sock); }
+static void cleanup_ifaces(int sock, struct Interface *ifaces) { for_each_iface(ifaces, cleanup_iface_foo, &sock); }
 
 static struct Interface *reload_config(int sock, struct Interface *ifaces, char const *conf_path)
 {
+	cleanup_ifaces(sock, ifaces);
 	free_ifaces(ifaces);
 
 	flog(LOG_INFO, "attempting to reread config file");
diff --git a/radvd.h b/radvd.h
index 2a61c75..d16a5c6 100644
--- a/radvd.h
+++ b/radvd.h
@@ -286,6 +286,7 @@ int set_interface_linkmtu(const char *, uint32_t);
 int set_interface_reachtime(const char *, uint32_t);
 int set_interface_retranstimer(const char *, uint32_t);
 int setup_allrouters_membership(int sock, struct Interface *);
+int cleanup_allrouters_membership(int sock, struct Interface *iface);
 int setup_iface_addrs(struct Interface *);
 int update_device_index(struct Interface *iface);
 int update_device_info(int sock, struct Interface *);
@@ -296,6 +297,7 @@ int get_iface_addrs(char const *name, struct in6_addr *if_addr, /* the first lin
 /* interface.c */
 int check_iface(struct Interface *);
 int setup_iface(int sock, struct Interface *iface);
+int cleanup_iface(int sock, struct Interface *iface);
 struct Interface *find_iface_by_index(struct Interface *iface, int index);
 struct Interface *find_iface_by_name(struct Interface *iface, const char *name);
 struct Interface *find_iface_by_time(struct Interface *iface_list);
-- 
2.27.0