void gnrc_ipv6_demux(kernel_pid_t iface, gnrc_pktsnip_t *pkt, uint8_t nh)
{
int receiver_num;
pkt->type = gnrc_nettype_from_protnum(nh);
switch (nh) {
#ifdef MODULE_GNRC_ICMPV6
case PROTNUM_ICMPV6:
DEBUG("ipv6: handle ICMPv6 packet (nh = %" PRIu8 ")\n", nh);
gnrc_icmpv6_demux(iface, pkt);
break;
#endif
#ifdef MODULE_GNRC_IPV6_EXT
case PROTNUM_IPV6_EXT_HOPOPT:
case PROTNUM_IPV6_EXT_DST:
case PROTNUM_IPV6_EXT_RH:
case PROTNUM_IPV6_EXT_FRAG:
case PROTNUM_IPV6_EXT_AH:
case PROTNUM_IPV6_EXT_ESP:
case PROTNUM_IPV6_EXT_MOB:
DEBUG("ipv6: handle extension header (nh = %" PRIu8 ")\n", nh);
if (!gnrc_ipv6_ext_demux(iface, pkt, nh)) {
DEBUG("ipv6: unable to parse extension headers.\n");
gnrc_pktbuf_release(pkt);
return;
}
#endif
case PROTNUM_IPV6:
DEBUG("ipv6: handle encapsulated IPv6 packet (nh = %" PRIu8 ")\n", nh);
_decapsulate(pkt);
break;
default:
(void)iface;
break;
}
DEBUG("ipv6: forward nh = %" PRIu8 " to other threads\n", nh);
receiver_num = gnrc_netreg_num(pkt->type, GNRC_NETREG_DEMUX_CTX_ALL) +
gnrc_netreg_num(GNRC_NETTYPE_IPV6, nh);
if (receiver_num == 0) {
DEBUG("ipv6: unable to forward packet as no one is interested in it\n");
gnrc_pktbuf_release(pkt);
return;
}
gnrc_pktbuf_hold(pkt, receiver_num - 1); /* IPv6 is not interested anymore so `- 1` */
/* XXX can't use gnrc_netapi_dispatch_receive() twice here since a call to that function
* implicitly hands all rights to the packet to one of the receiving threads. As a result,
* the second call to gnrc_netapi_dispatch_receive() would be invalid */
_dispatch_rcv_pkt(pkt->type, GNRC_NETREG_DEMUX_CTX_ALL, pkt);
_dispatch_rcv_pkt(GNRC_NETTYPE_IPV6, nh, pkt);
}
/*
* current pkt
* | |
* v v
* IPv6 <- IPv6_EXT <- IPv6_EXT <- UNDEF
*/
void gnrc_ipv6_demux(kernel_pid_t iface, gnrc_pktsnip_t *current, gnrc_pktsnip_t *pkt, uint8_t nh)
{
bool interested = false;
current->type = gnrc_nettype_from_protnum(nh);
switch (nh) {
#ifdef MODULE_GNRC_ICMPV6
case PROTNUM_ICMPV6:
assert(current == pkt);
interested = true;
break;
#endif
#ifdef MODULE_GNRC_IPV6_EXT
case PROTNUM_IPV6_EXT_HOPOPT:
case PROTNUM_IPV6_EXT_DST:
case PROTNUM_IPV6_EXT_RH:
case PROTNUM_IPV6_EXT_FRAG:
case PROTNUM_IPV6_EXT_AH:
case PROTNUM_IPV6_EXT_ESP:
case PROTNUM_IPV6_EXT_MOB:
interested = true;
break;
#endif
case PROTNUM_IPV6:
assert(current == pkt);
interested = true;
break;
default:
(void)iface;
#ifdef MODULE_GNRC_SIXLOWPAN_IPHC_NHC
/* second statement is true for small 6LoWPAN NHC decompressed frames
* since in this case it looks like
*
* * GNRC_NETTYPE_UNDEF <- pkt
* v
* * GNRC_NETTYPE_UDP <- current
* v
* * GNRC_NETTYPE_EXT
* v
* * GNRC_NETTYPE_IPV6
*/
assert((current == pkt) || (current == pkt->next));
#else
assert(current == pkt);
#endif
break;
}
_dispatch_next_header(current, pkt, nh, interested);
if (!interested) {
return;
}
switch (nh) {
#ifdef MODULE_GNRC_ICMPV6
case PROTNUM_ICMPV6:
DEBUG("ipv6: handle ICMPv6 packet (nh = %u)\n", nh);
gnrc_icmpv6_demux(iface, pkt);
gnrc_pktbuf_release(pkt);
return;
#endif
#ifdef MODULE_GNRC_IPV6_EXT
case PROTNUM_IPV6_EXT_HOPOPT:
case PROTNUM_IPV6_EXT_DST:
case PROTNUM_IPV6_EXT_RH:
case PROTNUM_IPV6_EXT_FRAG:
case PROTNUM_IPV6_EXT_AH:
case PROTNUM_IPV6_EXT_ESP:
case PROTNUM_IPV6_EXT_MOB:
DEBUG("ipv6: handle extension header (nh = %u)\n", nh);
gnrc_ipv6_ext_demux(iface, current, pkt, nh);
return;
#endif
case PROTNUM_IPV6:
DEBUG("ipv6: handle encapsulated IPv6 packet (nh = %u)\n", nh);
_decapsulate(pkt);
return;
default:
assert(false);
break;
}
assert(false);
}