Multicast listener discovery for IPv6.

Aims to be compliant with RFC 2710. No support for MLDv2.

#include "lwip/opt.h"
#include "lwip/mld6.h"
#include "lwip/icmp6.h"
#include "lwip/ip6.h"
#include "lwip/ip6_addr.h"
#include "lwip/ip.h"
#include "lwip/inet_chksum.h"
#include "lwip/pbuf.h"
#include "lwip/netif.h"
#include "lwip/memp.h"
#include "lwip/stats.h"
#include <string.h>

Macros
#define	MLD6_GROUP_DELAYING_MEMBER 1

#define	MLD6_GROUP_IDLE_MEMBER 2

#define	MLD6_GROUP_NON_MEMBER 0

#define	MLD6_HL 1

#define	MLD6_JOIN_DELAYING_MEMBER_TMR_MS (500)

Functions
static void	mld6_delayed_report (struct mld_group *group, u16_t maxresp)
	Schedule a delayed membership report for a group. More...

static err_t	mld6_free_group (struct mld_group *group)
	Remove a group in the mld_group_list and free. More...

void	mld6_input (struct pbuf p, struct netif inp)
	Process an input MLD message. More...

err_t	mld6_joingroup (ip6_addr_t srcaddr, ip6_addr_t groupaddr)
	Join a group on a network interface. More...

err_t	mld6_leavegroup (ip6_addr_t srcaddr, ip6_addr_t groupaddr)
	Leave a group on a network interface. More...

struct mld_group *	mld6_lookfor_group (struct netif ifp, ip6_addr_t addr)
	Search for a group that is joined on a netif. More...

static struct mld_group *	mld6_new_group (struct netif ifp, ip6_addr_t addr)
	create a new group More...

void	mld6_report_groups (struct netif *netif)
	Report MLD memberships for this interface. More...

static void	mld6_send (struct mld_group *group, u8_t type)
	Send a MLD message (report or done). More...

err_t	mld6_stop (struct netif *netif)
	Stop MLD processing on interface. More...

void	mld6_tmr (void)
	Periodic timer for mld processing. More...

Variables
static struct mld_group *	mld_group_list

#define MLD6_GROUP_DELAYING_MEMBER 1

Referenced by mld6_delayed_report(), mld6_input(), and mld6_tmr().

#define MLD6_GROUP_IDLE_MEMBER 2

Referenced by mld6_delayed_report(), mld6_input(), mld6_new_group(), and mld6_tmr().

#define MLD6_GROUP_NON_MEMBER 0

#define MLD6_HL 1

Referenced by mld6_send().

#define MLD6_JOIN_DELAYING_MEMBER_TMR_MS (500)

Referenced by mld6_joingroup(), and mld6_report_groups().

static void mld6_delayed_report	(	struct mld_group *	group,
		u16_t	maxresp
	)

static

Schedule a delayed membership report for a group.

Parameters

group	the mld_group for which "delaying" membership report should be sent
maxresp	the max resp delay provided in the query

References mld_group::group_state, LWIP_RAND, MLD6_GROUP_DELAYING_MEMBER, MLD6_GROUP_IDLE_MEMBER, MLD6_TMR_INTERVAL, and mld_group::timer.

Referenced by mld6_input(), mld6_joingroup(), and mld6_report_groups().

static err_t mld6_free_group ( struct mld_group * group )

static

Remove a group in the mld_group_list and free.

Parameters

group the group to remove

Returns: ERR_OK if group was removed from the list, an err_t otherwise

References ERR_ARG, ERR_OK, memp_free(), mld_group::next, and NULL.

Referenced by mld6_leavegroup().

void mld6_input	(	struct pbuf *	p,
		struct netif *	inp
	)

Process an input MLD message.

Called by icmp6_input.

Parameters

p	the mld packet, p->payload pointing to the icmpv6 header
inp	the netif on which this packet was received

References mld_group::group_address, mld_group::group_state, ICMP6_TYPE_MLD, ICMP6_TYPE_MLQ, ICMP6_TYPE_MLR, ip6_addr_isallnodes_linklocal, ip6_addr_isany, ip6_addr_ismulticast_iflocal, ip6_current_dest_addr, mld_group::last_reporter_flag, pbuf::len, mld6_delayed_report(), MLD6_GROUP_DELAYING_MEMBER, MLD6_GROUP_IDLE_MEMBER, mld6_lookfor_group(), MLD6_STATS_INC, mld_group_list, mld_group::netif, mld_group::next, NULL, pbuf::payload, pbuf_free(), and mld_group::timer.

Referenced by icmp6_input().

err_t mld6_joingroup	(	ip6_addr_t *	srcaddr,
		ip6_addr_t *	groupaddr
	)

Join a group on a network interface.

Parameters

srcaddr	ipv6 address of the network interface which should join a new group. If IP6_ADDR_ANY, join on all netifs
groupaddr	the ipv6 address of the group to join

Returns: ERR_OK if group was joined on the netif(s), an err_t otherwise

References ERR_MEM, ERR_OK, ERR_VAL, ICMP6_TYPE_MLR, ip6_addr_cmp, ip6_addr_isany, MLD6_ADD_MAC_FILTER, mld6_delayed_report(), MLD6_JOIN_DELAYING_MEMBER_TMR_MS, mld6_lookfor_group(), mld6_new_group(), mld6_send(), MLD6_STATS_INC, netif::mld_mac_filter, netif_ip6_addr, netif_list, netif::next, NULL, and mld_group::use.

Referenced by lwip_netconn_do_join_leave_group(), and nd6_tmr().

err_t mld6_leavegroup	(	ip6_addr_t *	srcaddr,
		ip6_addr_t *	groupaddr
	)

Leave a group on a network interface.

Parameters

srcaddr	ipv6 address of the network interface which should leave the group. If IP6_ISANY, leave on all netifs
groupaddr	the ipv6 address of the group to leave