void
icmp6_proxy_input(struct pbuf *p, struct netif *inp)
{
struct icmp6_hdr *icmp6hdr;
ICMP6_STATS_INC(icmp6.recv);
/* Check that ICMPv6 header fits in payload */
if (p->len < sizeof(struct icmp6_hdr)) {
/* drop short packets */
pbuf_free(p);
ICMP6_STATS_INC(icmp6.lenerr);
ICMP6_STATS_INC(icmp6.drop);
return;
}
icmp6hdr = (struct icmp6_hdr *)p->payload;
if (ip6_chksum_pseudo(p, IP6_NEXTH_ICMP6, p->tot_len, ip6_current_src_addr(),
ip6_current_dest_addr()) != 0) {
/* Checksum failed */
pbuf_free(p);
ICMP6_STATS_INC(icmp6.chkerr);
ICMP6_STATS_INC(icmp6.drop);
return;
}
switch (icmp6hdr->type) {
case ICMP6_TYPE_EREQ:
if (ping6_proxy_accept_callback != NULL) {
(*ping6_proxy_accept_callback)(ping6_proxy_accept_arg, p);
return;
}
ICMP6_STATS_INC(icmp6.drop);
break;
case ICMP6_TYPE_EREP:
/* ignore silently */
ICMP6_STATS_INC(icmp6.drop);
break;
default:
ICMP6_STATS_INC(icmp6.drop);
break;
}
pbuf_free(p);
}
/**
* Process an input ICMPv6 message. Called by ip6_input.
*
* Will generate a reply for echo requests. Other messages are forwarded
* to nd6_input, or mld6_input.
*
* @param p the mld packet, p->payload pointing to the icmpv6 header
* @param inp the netif on which this packet was received
*/
void
icmp6_input(struct pbuf *p, struct interface *inp)
{
struct icmp6_hdr *icmp6hdr;
struct pbuf * r;
ip6_addr_t * reply_src;
ICMP6_STATS_INC(icmp6.recv);
/* Check that ICMPv6 header fits in payload */
if (p->len < sizeof(struct icmp6_hdr)) {
/* drop short packets */
pbuf_free(p);
ICMP6_STATS_INC(icmp6.lenerr);
ICMP6_STATS_INC(icmp6.drop);
return;
}
icmp6hdr = (struct icmp6_hdr *)p->payload;
#if LWIP_ICMP6_CHECKSUM_CHECK
if (ip6_chksum_pseudo(p, IP6_NEXTH_ICMP6, p->tot_len, ip6_current_src_addr(),
ip6_current_dest_addr()) != 0) {
/* Checksum failed */
pbuf_free(p);
ICMP6_STATS_INC(icmp6.chkerr);
ICMP6_STATS_INC(icmp6.drop);
return;
}
#endif /* LWIP_ICMP6_CHECKSUM_CHECK */
switch (icmp6hdr->type) {
case ICMP6_TYPE_NA: /* Neighbor advertisement */
case ICMP6_TYPE_NS: /* Neighbor solicitation */
case ICMP6_TYPE_RA: /* Router advertisement */
case ICMP6_TYPE_RD: /* Redirect */
case ICMP6_TYPE_PTB: /* Packet too big */
nd6_input(p, inp);
return;
break;
case ICMP6_TYPE_RS:
#if LWIP_IPV6_FORWARD
/* TODO implement router functionality */
#endif
break;
#if LWIP_IPV6_MLD
case ICMP6_TYPE_MLQ:
case ICMP6_TYPE_MLR:
case ICMP6_TYPE_MLD:
mld6_input(p, inp);
return;
break;
#endif
case ICMP6_TYPE_EREQ:
#if !LWIP_MULTICAST_PING
/* multicast destination address? */
if (ip6_addr_ismulticast(ip6_current_dest_addr())) {
/* drop */
pbuf_free(p);
ICMP6_STATS_INC(icmp6.drop);
return;
}
#endif /* LWIP_MULTICAST_PING */
/* Allocate reply. */
r = pbuf_alloc(PBUF_IP, p->tot_len, PBUF_RAM);
if (r == NULL) {
/* drop */
pbuf_free(p);
ICMP6_STATS_INC(icmp6.memerr);
return;
}
/* Copy echo request. */
if (pbuf_copy(r, p) != ERR_OK) {
/* drop */
pbuf_free(p);
pbuf_free(r);
ICMP6_STATS_INC(icmp6.err);
return;
}
/* Determine reply source IPv6 address. */
#if LWIP_MULTICAST_PING
if (ip6_addr_ismulticast(ip6_current_dest_addr())) {
reply_src = ip6_select_source_address(inp, ip6_current_src_addr());
if (reply_src == NULL) {
/* drop */
pbuf_free(p);
pbuf_free(r);
ICMP6_STATS_INC(icmp6.rterr);
return;
}
}
else
#endif /* LWIP_MULTICAST_PING */
{
reply_src = ip6_current_dest_addr();
}
/* Set fields in reply. */
((struct icmp6_echo_hdr *)(r->payload))->type = ICMP6_TYPE_EREP;
((struct icmp6_echo_hdr *)(r->payload))->chksum = 0;
((struct icmp6_echo_hdr *)(r->payload))->chksum = ip6_chksum_pseudo(r,
IP6_NEXTH_ICMP6, r->tot_len, reply_src, ip6_current_src_addr());
/* Send reply. */
ICMP6_STATS_INC(icmp6.xmit);
ip6_output_if(r, reply_src, ip6_current_src_addr(),
LWIP_ICMP6_HL, 0, IP6_NEXTH_ICMP6, inp);
pbuf_free(r);
break;
default:
ICMP6_STATS_INC(icmp6.proterr);
ICMP6_STATS_INC(icmp6.drop);
break;
}
pbuf_free(p);
}
/**
* Send an ICMPv6 packet in response to an incoming packet.
*
* @param p the input packet for which the response should be sent,
* p->payload pointing to the IPv6 header
* @param code Code of the ICMPv6 header
* @param data Additional 32-bit parameter in the ICMPv6 header
* @param type Type of the ICMPv6 header
*/
static void
icmp6_send_response(struct pbuf *p, u8_t code, u32_t data, u8_t type)
{
struct pbuf *q;
struct icmp6_hdr *icmp6hdr;
ip6_addr_t *reply_src, *reply_dest;
ip6_addr_t reply_src_local, reply_dest_local;
struct ip6_hdr *ip6hdr;
struct interface *netif;
/* ICMPv6 header + IPv6 header + data */
q = pbuf_alloc(PBUF_IP, sizeof(struct icmp6_hdr) + IP6_HLEN + LWIP_ICMP6_DATASIZE,
PBUF_RAM);
if (q == NULL) {
LWIP_DEBUGF(ICMP_DEBUG, ("icmp_time_exceeded: failed to allocate pbuf for ICMPv6 packet.\n"));
ICMP6_STATS_INC(icmp6.memerr);
return;
}
LWIP_ASSERT("check that first pbuf can hold icmp 6message",
(q->len >= (sizeof(struct icmp6_hdr) + IP6_HLEN + LWIP_ICMP6_DATASIZE)));
icmp6hdr = (struct icmp6_hdr *)q->payload;
icmp6hdr->type = type;
icmp6hdr->code = code;
icmp6hdr->data = data;
/* copy fields from original packet */
SMEMCPY((u8_t *)q->payload + sizeof(struct icmp6_hdr), (u8_t *)p->payload,
IP6_HLEN + LWIP_ICMP6_DATASIZE);
/* Get the destination address and netif for this ICMP message. */
if ((ip_current_netif() == NULL) ||
((code == ICMP6_TE_FRAG) && (type == ICMP6_TYPE_TE))) {
/* Special case, as ip6_current_xxx is either NULL, or points
* to a different packet than the one that expired.
* We must use the addresses that are stored in the expired packet. */
ip6hdr = (struct ip6_hdr *)p->payload;
/* copy from packed address to aligned address */
ip6_addr_copy(reply_dest_local, ip6hdr->src);
ip6_addr_copy(reply_src_local, ip6hdr->dest);
reply_dest = &reply_dest_local;
reply_src = &reply_src_local;
netif = ip6_route(reply_src, reply_dest);
if (netif == NULL) {
/* drop */
pbuf_free(q);
ICMP6_STATS_INC(icmp6.rterr);
return;
}
}
else {
netif = ip_current_netif();
reply_dest = ip6_current_src_addr();
/* Select an address to use as source. */
reply_src = ip6_select_source_address(netif, reply_dest);
if (reply_src == NULL) {
/* drop */
pbuf_free(q);
ICMP6_STATS_INC(icmp6.rterr);
return;
}
}
/* calculate checksum */
icmp6hdr->chksum = 0;
icmp6hdr->chksum = ip6_chksum_pseudo(q, IP6_NEXTH_ICMP6, q->tot_len,
reply_src, reply_dest);
ICMP6_STATS_INC(icmp6.xmit);
ip6_output_if(q, reply_src, reply_dest, LWIP_ICMP6_HL, 0, IP6_NEXTH_ICMP6, netif);
pbuf_free(q);
}
