net: ipv4: Add IGMPv2 support

Add Internet Group Management Protocol v2 support, see RFC 2236
for details.

Fixes #2336

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>

include/net/igmp.h

@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2021 Intel Corporation
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/** @file
+ * @brief IGMP API
+ */
+
+#ifndef ZEPHYR_INCLUDE_NET_IGMP_H_
+#define ZEPHYR_INCLUDE_NET_IGMP_H_
+
+/**
+ * @brief IGMP (Internet Group Management Protocol)
+ * @defgroup igmp IGMP API
+ * @ingroup networking
+ * @{
+ */
+
+#include <zephyr/types.h>
+
+#include <net/net_if.h>
+#include <net/net_ip.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief Join a given multicast group.
+ *
+ * @param iface Network interface where join message is sent
+ * @param addr Multicast group to join
+ *
+ * @return Return 0 if joining was done, <0 otherwise.
+ */
+#if defined(CONFIG_NET_IPV4_IGMP)
+int net_ipv4_igmp_join(struct net_if *iface, const struct in_addr *addr);
+#else
+#define net_ipv4_igmp_join(iface, addr) -ENOSYS
+#endif
+
+/**
+ * @brief Leave a given multicast group.
+ *
+ * @param iface Network interface where leave message is sent
+ * @param addr Multicast group to leave
+ *
+ * @return Return 0 if leaving is done, <0 otherwise.
+ */
+#if defined(CONFIG_NET_IPV4_IGMP)
+int net_ipv4_igmp_leave(struct net_if *iface, const struct in_addr *addr);
+#else
+#define net_ipv4_igmp_leave(iface, addr) -ENOSYS
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+/**
+ * @}
+ */
+
+#endif /* ZEPHYR_INCLUDE_NET_IGMP_H_ */

include/net/net_event.h

@@ -135,6 +135,8 @@ enum net_event_ipv4_cmd {
 	NET_EVENT_IPV4_CMD_DHCP_START,
 	NET_EVENT_IPV4_CMD_DHCP_BOUND,
 	NET_EVENT_IPV4_CMD_DHCP_STOP,
+	NET_EVENT_IPV4_CMD_MCAST_JOIN,
+	NET_EVENT_IPV4_CMD_MCAST_LEAVE,
 };
 
 #define NET_EVENT_IPV4_ADDR_ADD					\
@@ -158,6 +160,12 @@ enum net_event_ipv4_cmd {
 #define NET_EVENT_IPV4_DHCP_STOP				\
 	(_NET_EVENT_IPV4_BASE |	NET_EVENT_IPV4_CMD_DHCP_STOP)
 
+#define NET_EVENT_IPV4_MCAST_JOIN				\
+	(_NET_EVENT_IPV4_BASE |	NET_EVENT_IPV4_CMD_MCAST_JOIN)
+
+#define NET_EVENT_IPV4_MCAST_LEAVE				\
+	(_NET_EVENT_IPV4_BASE |	NET_EVENT_IPV4_CMD_MCAST_LEAVE)
+
 
 /* L4 network events */
 #define _NET_L4_LAYER		NET_MGMT_LAYER_L4

include/net/net_ip.h

@@ -62,6 +62,7 @@ extern "C" {
 enum net_ip_protocol {
 	IPPROTO_IP = 0,            /**< IP protocol (pseudo-val for setsockopt() */
 	IPPROTO_ICMP = 1,          /**< ICMP protocol   */
+	IPPROTO_IGMP = 2,          /**< IGMP protocol   */
 	IPPROTO_IPIP = 4,          /**< IPIP tunnels    */
 	IPPROTO_TCP = 6,           /**< TCP protocol    */
 	IPPROTO_UDP = 17,          /**< UDP protocol    */