blob: e2b46b1e725f5ac4fe1cc8f98ead05845ff207cb [file] [log] [blame]
/** @file
* @brief IPv4 IGMP related functions
*/
/*
* Copyright (c) 2021 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr/logging/log.h>
LOG_MODULE_DECLARE(net_ipv4, CONFIG_NET_IPV4_LOG_LEVEL);
#include <errno.h>
#include <zephyr/net/net_core.h>
#include <zephyr/net/net_pkt.h>
#include <zephyr/net/net_stats.h>
#include <zephyr/net/net_context.h>
#include <zephyr/net/net_mgmt.h>
#include <zephyr/net/igmp.h>
#include "net_private.h"
#include "connection.h"
#include "ipv4.h"
#include "net_stats.h"
/* Timeout for various buffer allocations in this file. */
#define PKT_WAIT_TIME K_MSEC(50)
#define IPV4_OPT_HDR_ROUTER_ALERT_LEN 4
static const struct in_addr all_systems = { { { 224, 0, 0, 1 } } };
static const struct in_addr all_routers = { { { 224, 0, 0, 2 } } };
#define dbg_addr(action, pkt_str, src, dst) \
NET_DBG("%s %s from %s to %s", action, pkt_str, \
net_sprint_ipv4_addr(src), \
net_sprint_ipv4_addr(dst));
#define dbg_addr_recv(pkt_str, src, dst) \
dbg_addr("Received", pkt_str, src, dst)
static int igmp_v2_create(struct net_pkt *pkt, const struct in_addr *addr,
uint8_t type)
{
NET_PKT_DATA_ACCESS_DEFINE(igmp_access,
struct net_ipv4_igmp_v2_report);
struct net_ipv4_igmp_v2_report *igmp;
igmp = (struct net_ipv4_igmp_v2_report *)
net_pkt_get_data(pkt, &igmp_access);
if (!igmp) {
return -ENOBUFS;
}
igmp->type = type;
igmp->max_rsp = 0U;
net_ipaddr_copy(&igmp->address, addr);
igmp->chksum = 0;
igmp->chksum = net_calc_chksum_igmp((uint8_t *)igmp, sizeof(*igmp));
if (net_pkt_set_data(pkt, &igmp_access)) {
return -ENOBUFS;
}
return 0;
}
static int igmp_v2_create_packet(struct net_pkt *pkt, const struct in_addr *dst,
const struct in_addr *group, uint8_t type)
{
const uint32_t router_alert = 0x94040000; /* RFC 2213 ch 2.1 */
int ret;
ret = net_ipv4_create_full(pkt,
net_if_ipv4_select_src_addr(
net_pkt_iface(pkt),
dst),
dst,
0U,
0U,
0U,
0U,
1U); /* TTL set to 1, RFC 3376 ch 2 */
if (ret) {
return -ENOBUFS;
}
/* Add router alert option, RFC 3376 ch 2 */
if (net_pkt_write_be32(pkt, router_alert)) {
return -ENOBUFS;
}
net_pkt_set_ipv4_opts_len(pkt, IPV4_OPT_HDR_ROUTER_ALERT_LEN);
return igmp_v2_create(pkt, group, type);
}
static int igmp_send(struct net_pkt *pkt)
{
int ret;
net_pkt_cursor_init(pkt);
net_ipv4_finalize(pkt, IPPROTO_IGMP);
ret = net_send_data(pkt);
if (ret < 0) {
net_stats_update_ipv4_igmp_drop(net_pkt_iface(pkt));
net_pkt_unref(pkt);
return ret;
}
net_stats_update_ipv4_igmp_sent(net_pkt_iface(pkt));
return 0;
}
static int send_igmp_report(struct net_if *iface,
struct net_ipv4_igmp_v2_query *igmp_v2_hdr)
{
struct net_if_ipv4 *ipv4 = iface->config.ip.ipv4;
struct net_pkt *pkt = NULL;
int i, count = 0;
int ret = 0;
if (!ipv4) {
return -ENOENT;
}
for (i = 0; i < NET_IF_MAX_IPV4_MADDR; i++) {
/* We don't need to send an IGMP membership report to the IGMP
* all systems multicast address of 224.0.0.1 so skip over it.
* Since the IGMP all systems multicast address is marked as
* used and joined during init time, we have to check this
* address separately to skip over it.
*/
if (!ipv4->mcast[i].is_used || !ipv4->mcast[i].is_joined ||
net_ipv4_addr_cmp_raw((uint8_t *)&ipv4->mcast[i].address.in_addr,
(uint8_t *)&all_systems)) {
continue;
}
count++;
}
if (count == 0) {
return -ESRCH;
}
for (i = 0; i < NET_IF_MAX_IPV4_MADDR; i++) {
/* We don't need to send an IGMP membership report to the IGMP
* all systems multicast address of 224.0.0.1 so skip over it.
* Since the IGMP all systems multicast address is marked as
* used and joined during init time, we have to check this
* address separately to skip over it.
*/
if (!ipv4->mcast[i].is_used || !ipv4->mcast[i].is_joined ||
net_ipv4_addr_cmp_raw((uint8_t *)&ipv4->mcast[i].address.in_addr,
(uint8_t *)&all_systems)) {
continue;
}
pkt = net_pkt_alloc_with_buffer(iface,
IPV4_OPT_HDR_ROUTER_ALERT_LEN +
sizeof(struct net_ipv4_igmp_v2_report),
AF_INET, IPPROTO_IGMP,
PKT_WAIT_TIME);
if (!pkt) {
return -ENOMEM;
}
/* Send the IGMP V2 membership report to the group multicast
* address, as per RFC 2236 Section 9.
*/
ret = igmp_v2_create_packet(pkt, &ipv4->mcast[i].address.in_addr,
&ipv4->mcast[i].address.in_addr,
NET_IPV4_IGMP_REPORT_V2);
if (ret < 0) {
goto drop;
}
ret = igmp_send(pkt);
if (ret < 0) {
goto drop;
}
/* So that we do not free the data while it is being sent */
pkt = NULL;
}
drop:
if (pkt) {
net_pkt_unref(pkt);
}
return ret;
}
enum net_verdict net_ipv4_igmp_input(struct net_pkt *pkt,
struct net_ipv4_hdr *ip_hdr)
{
NET_PKT_DATA_ACCESS_CONTIGUOUS_DEFINE(igmp_access,
struct net_ipv4_igmp_v2_query);
struct net_ipv4_igmp_v2_query *igmp_hdr;
/* TODO: receive from arbitrary group address instead of
* all_systems
*/
if (!net_ipv4_addr_cmp_raw(ip_hdr->dst, (uint8_t *)&all_systems)) {
NET_DBG("DROP: Invalid dst address");
return NET_DROP;
}
igmp_hdr = (struct net_ipv4_igmp_v2_query *)net_pkt_get_data(pkt,
&igmp_access);
if (!igmp_hdr) {
NET_DBG("DROP: NULL IGMP header");
return NET_DROP;
}
if (net_calc_chksum_igmp((uint8_t *)igmp_hdr,
sizeof(*igmp_hdr)) != 0U) {
NET_DBG("DROP: Invalid checksum");
goto drop;
}
net_pkt_acknowledge_data(pkt, &igmp_access);
dbg_addr_recv("Internet Group Management Protocol", &ip_hdr->src,
&ip_hdr->dst);
net_stats_update_ipv4_igmp_recv(net_pkt_iface(pkt));
(void)send_igmp_report(net_pkt_iface(pkt), igmp_hdr);
net_pkt_unref(pkt);
return NET_OK;
drop:
net_stats_update_ipv4_igmp_drop(net_pkt_iface(pkt));
return NET_DROP;
}
static int igmp_send_generic(struct net_if *iface,
const struct in_addr *addr,
bool join)
{
struct net_pkt *pkt;
int ret;
pkt = net_pkt_alloc_with_buffer(iface,
IPV4_OPT_HDR_ROUTER_ALERT_LEN +
sizeof(struct net_ipv4_igmp_v2_report),
AF_INET, IPPROTO_IGMP,
PKT_WAIT_TIME);
if (!pkt) {
return -ENOMEM;
}
/* Send the IGMP V2 membership report to the group multicast
* address, as per RFC 2236 Section 9. The leave report
* should be sent to the ALL ROUTERS multicast address (224.0.0.2)
*/
ret = igmp_v2_create_packet(pkt,
join ? addr : &all_routers, addr,
join ? NET_IPV4_IGMP_REPORT_V2 : NET_IPV4_IGMP_LEAVE);
if (ret < 0) {
goto drop;
}
ret = igmp_send(pkt);
if (ret < 0) {
goto drop;
}
return 0;
drop:
net_pkt_unref(pkt);
return ret;
}
int net_ipv4_igmp_join(struct net_if *iface, const struct in_addr *addr)
{
struct net_if_mcast_addr *maddr;
int ret;
maddr = net_if_ipv4_maddr_lookup(addr, &iface);
if (maddr && net_if_ipv4_maddr_is_joined(maddr)) {
return -EALREADY;
}
if (!maddr) {
maddr = net_if_ipv4_maddr_add(iface, addr);
if (!maddr) {
return -ENOMEM;
}
}
ret = igmp_send_generic(iface, addr, true);
if (ret < 0) {
return ret;
}
net_if_ipv4_maddr_join(maddr);
net_if_mcast_monitor(iface, &maddr->address, true);
net_mgmt_event_notify_with_info(NET_EVENT_IPV4_MCAST_JOIN, iface,
&maddr->address.in_addr,
sizeof(struct in_addr));
return ret;
}
int net_ipv4_igmp_leave(struct net_if *iface, const struct in_addr *addr)
{
struct net_if_mcast_addr *maddr;
int ret;
maddr = net_if_ipv4_maddr_lookup(addr, &iface);
if (!maddr) {
return -ENOENT;
}
if (!net_if_ipv4_maddr_rm(iface, addr)) {
return -EINVAL;
}
ret = igmp_send_generic(iface, addr, false);
if (ret < 0) {
return ret;
}
net_if_ipv4_maddr_leave(maddr);
net_if_mcast_monitor(iface, &maddr->address, false);
net_mgmt_event_notify_with_info(NET_EVENT_IPV4_MCAST_LEAVE, iface,
&maddr->address.in_addr,
sizeof(struct in_addr));
return ret;
}
void net_ipv4_igmp_init(struct net_if *iface)
{
struct net_if_mcast_addr *maddr;
/* Ensure multicast addresses are available */
if (CONFIG_NET_IF_MCAST_IPV4_ADDR_COUNT < 1) {
return;
}
/* This code adds the IGMP all systems 224.0.0.1 multicast address
* to the list of multicast addresses of the given interface.
* The address is marked as joined. However, an IGMP membership
* report is not generated for this address. Populating this
* address in the list of multicast addresses of the interface
* and marking it as joined is helpful for multicast hash filter
* implementations that need a list of multicast addresses it needs
* to add to the multicast hash filter after a multicast address
* has been removed from the membership list.
*/
maddr = net_if_ipv4_maddr_lookup(&all_systems, &iface);
if (maddr && net_if_ipv4_maddr_is_joined(maddr)) {
return;
}
if (!maddr) {
maddr = net_if_ipv4_maddr_add(iface, &all_systems);
if (!maddr) {
return;
}
}
net_if_ipv4_maddr_join(maddr);
net_if_mcast_monitor(iface, &maddr->address, true);
}