/**
* Send a MLD message (report or done).
*
* An IPv6 hop-by-hop options header with a router alert option
* is prepended.
*
* @param group the group to report or quit
* @param type ICMP6_TYPE_MLR (report) or ICMP6_TYPE_MLD (done)
*/
static void
mld6_send(struct mld_group *group, u8_t type)
{
struct mld_header * mld_hdr;
struct pbuf * p;
ip6_addr_t * src_addr;
/* Allocate a packet. Size is MLD header + IPv6 Hop-by-hop options header. */
p = pbuf_alloc(PBUF_IP, sizeof(struct mld_header) + sizeof(struct ip6_hbh_hdr), PBUF_RAM);
if ((p == NULL) || (p->len < (sizeof(struct mld_header) + sizeof(struct ip6_hbh_hdr)))) {
/* We couldn't allocate a suitable pbuf. drop it. */
if (p != NULL) {
pbuf_free(p);
}
MLD6_STATS_INC(mld6.memerr);
return;
}
/* Move to make room for Hop-by-hop options header. */
if (pbuf_header(p, -IP6_HBH_HLEN)) {
pbuf_free(p);
MLD6_STATS_INC(mld6.lenerr);
return;
}
/* Select our source address. */
if (!ip6_addr_isvalid(netif_ip6_addr_state(group->netif, 0))) {
/* This is a special case, when we are performing duplicate address detection.
* We must join the multicast group, but we don't have a valid address yet. */
src_addr = IP6_ADDR_ANY;
} else {
/* Use link-local address as source address. */
src_addr = netif_ip6_addr(group->netif, 0);
}
/* MLD message header pointer. */
mld_hdr = (struct mld_header *)p->payload;
/* Set fields. */
mld_hdr->type = type;
mld_hdr->code = 0;
mld_hdr->chksum = 0;
mld_hdr->max_resp_delay = 0;
mld_hdr->reserved = 0;
ip6_addr_set(&(mld_hdr->multicast_address), &(group->group_address));
#if CHECKSUM_GEN_ICMP6
mld_hdr->chksum = ip6_chksum_pseudo(p, IP6_NEXTH_ICMP6, p->len,
src_addr, &(group->group_address));
#endif /* CHECKSUM_GEN_ICMP6 */
/* Add hop-by-hop headers options: router alert with MLD value. */
ip6_options_add_hbh_ra(p, IP6_NEXTH_ICMP6, IP6_ROUTER_ALERT_VALUE_MLD);
/* Send the packet out. */
MLD6_STATS_INC(mld6.xmit);
ip6_output_if(p, (ip6_addr_isany(src_addr)) ? NULL : src_addr, &(group->group_address),
MLD6_HL, 0, IP6_NEXTH_HOPBYHOP, group->netif);
pbuf_free(p);
}
/**
* Mapping from local network to loopback for outbound connections.
*
* Copy "src" to "dst" with ip6_addr_set(dst, src), but if "src" is a
* local network address that maps host's loopback address, copy IPv6
* loopback address to "dst".
*/
int
pxremap_outbound_ip6(ip6_addr_t *dst, ip6_addr_t *src)
{
struct netif *netif;
int i;
LWIP_ASSERT1(dst != NULL);
LWIP_ASSERT1(src != NULL);
for (netif = netif_list; netif != NULL; netif = netif->next) {
if (!netif_is_up(netif) /* || this is not a proxy netif */) {
continue;
}
for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; ++i) {
if (ip6_addr_ispreferred(netif_ip6_addr_state(netif, i))
&& ip6_addr_isuniquelocal(netif_ip6_addr(netif, i)))
{
ip6_addr_t *ifaddr = netif_ip6_addr(netif, i);
if (memcmp(src, ifaddr, sizeof(ip6_addr_t) - 1) == 0
&& ((IP6_ADDR_BLOCK8(src) & 0xff)
== (IP6_ADDR_BLOCK8(ifaddr) & 0xff) + 1))
{
ip6_addr_set_loopback(dst);
return PXREMAP_MAPPED;
}
}
}
}
/* not remapped, just copy src */
ip6_addr_set(dst, src);
return PXREMAP_ASIS;
}
err_t ip6_output_if(struct pbuf *p, struct ip6_addr *src, struct ip6_addr *dest, u8_t ttl, u8_t proto, struct netif *netif) {
struct ip6_hdr *iphdr;
PERF_START;
LWIP_DEBUGF(IP_DEBUG, ("len %"U16_F" tot_len %"U16_F"\n", p->len, p->tot_len));
if (pbuf_header(p, IP6_HLEN)) {
LWIP_DEBUGF(IP_DEBUG, ("ip_output: not enough room for IP header in pbuf\n"));IP_STATS_INC(ip.err);
return ERR_BUF;
}
LWIP_DEBUGF(IP_DEBUG, ("len %"U16_F" tot_len %"U16_F"\n", p->len, p->tot_len));
iphdr = p->payload;
if (dest != IP_HDRINCL) {
LWIP_DEBUGF(IP_DEBUG, ("!IP_HDRLINCL\n"));
iphdr->hoplim = ttl;
iphdr->nexthdr = proto;
iphdr->len = htons(p->tot_len - IP6_HLEN);
ip6_addr_set(&(iphdr->dest), dest);
iphdr->v = 6;
if (ip6_addr_isany(src)) {
ip6_addr_set(&(iphdr->src), &(netif->ip6_addr));
} else {
ip6_addr_set(&(iphdr->src), src);
}
} else {
dest = &(iphdr->dest);
}
IP_STATS_INC(ip.xmit);
LWIP_DEBUGF(IP_DEBUG, ("ip_output_if: %c%c (len %"U16_F")\n", netif->name[0], netif->name[1], p->tot_len));
#if IP_DEBUG
ip6_debug_print(p);
#endif /* IP_DEBUG */
PERF_STOP("ip_output_if");
if (netif->ip6_output != 0) {
return (netif->ip6_output(netif, p, dest));
} else {
return (ERR_RTE);
}
}
/**
* Mapping from loopback to local network for inbound (port-forwarded)
* connections.
*
* Copy "src" to "dst" with ip6_addr_set(dst, src), but if "src" is a
* host's loopback address, copy local network address that maps it to
* "dst".
*/
int
pxremap_inbound_ip6(ip6_addr_t *dst, ip6_addr_t *src)
{
ip6_addr_t loopback;
struct netif *netif;
int i;
ip6_addr_set_loopback(&loopback);
if (!ip6_addr_cmp(src, &loopback)) {
ip6_addr_set(dst, src);
return PXREMAP_ASIS;
}
#if 0 /* ?TODO: with multiple interfaces we need to consider fwspec::dst */
netif = ip6_route_fwd(target);
if (netif == NULL) {
return PXREMAP_FAILED;
}
#else
netif = netif_list;
LWIP_ASSERT1(netif != NULL);
LWIP_ASSERT1(netif->next == NULL);
#endif
for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; ++i) {
ip6_addr_t *ifaddr = netif_ip6_addr(netif, i);
if (ip6_addr_ispreferred(netif_ip6_addr_state(netif, i))
&& ip6_addr_isuniquelocal(ifaddr))
{
ip6_addr_set(dst, ifaddr);
++((u8_t *)&dst->addr[3])[3];
return PXREMAP_MAPPED;
}
}
return PXREMAP_FAILED;
}
/** Create a link-local IPv6 address on a netif (stored in slot 0)
*
* @param netif the netif to create the address on
* @param from_mac_48bit if != 0, assume hwadr is a 48-bit MAC address (std conversion)
* if == 0, use hwaddr directly as interface ID
*/
void
netif_create_ip6_linklocal_address(struct netif *netif, u8_t from_mac_48bit)
{
u8_t i, addr_index;
/* Link-local prefix. */
ip_2_ip6(&netif->ip6_addr[0])->addr[0] = PP_HTONL(0xfe800000ul);
ip_2_ip6(&netif->ip6_addr[0])->addr[1] = 0;
/* Generate interface ID. */
if (from_mac_48bit) {
/* Assume hwaddr is a 48-bit IEEE 802 MAC. Convert to EUI-64 address. Complement Group bit. */
ip_2_ip6(&netif->ip6_addr[0])->addr[2] = htonl((((u32_t)(netif->hwaddr[0] ^ 0x02)) << 24) |
((u32_t)(netif->hwaddr[1]) << 16) |
((u32_t)(netif->hwaddr[2]) << 8) |
(0xff));
ip_2_ip6(&netif->ip6_addr[0])->addr[3] = htonl((0xfeul << 24) |
((u32_t)(netif->hwaddr[3]) << 16) |
((u32_t)(netif->hwaddr[4]) << 8) |
(netif->hwaddr[5]));
} else {
/* Use hwaddr directly as interface ID. */
ip_2_ip6(&netif->ip6_addr[0])->addr[2] = 0;
ip_2_ip6(&netif->ip6_addr[0])->addr[3] = 0;
addr_index = 3;
for (i = 0; (i < 8) && (i < netif->hwaddr_len); i++) {
if (i == 4) {
addr_index--;
}
ip_2_ip6(&netif->ip6_addr[0])->addr[addr_index] |= ((u32_t)(netif->hwaddr[netif->hwaddr_len - i - 1])) << (8 * (i & 0x03));
}
}
#ifdef LWIP_ESP8266
ip6_addr_set( ip_2_ip6(&netif->link_local_addr), ip_2_ip6(&netif->ip6_addr[0]) );
#endif
/* Set address state. */
#if LWIP_IPV6_DUP_DETECT_ATTEMPTS
/* Will perform duplicate address detection (DAD). */
netif->ip6_addr_state[0] = IP6_ADDR_TENTATIVE;
#else
/* Consider address valid. */
netif->ip6_addr_state[0] = IP6_ADDR_PREFERRED;
#endif /* LWIP_IPV6_AUTOCONFIG */
}
/**
* create a new group
*
* @param ifp the network interface for which to create
* @param addr the new group ipv6
* @return a struct mld_group*,
* NULL on memory error.
*/
static struct mld_group *
mld6_new_group(struct netif *ifp, ip6_addr_t *addr)
{
struct mld_group *group;
group = (struct mld_group *)memp_malloc(MEMP_MLD6_GROUP);
if (group != NULL) {
group->netif = ifp;
ip6_addr_set(&(group->group_address), addr);
group->timer = 0; /* Not running */
group->group_state = MLD6_GROUP_IDLE_MEMBER;
group->last_reporter_flag = 0;
group->use = 0;
group->next = mld_group_list;
mld_group_list = group;
}
return group;
}
