/**
* @file
*
* IPv6 layer.
*/
/*
* Copyright (c) 2010 Inico Technologies Ltd.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* This file is part of the lwIP TCP/IP stack.
*
* Author: Ivan Delamer <delamer@inicotech.com>
*
*
* Please coordinate changes and requests with Ivan Delamer
* <delamer@inicotech.com>
*/
#include "lwip/opt.h"
#if LWIP_IPV6 /* don't build if not configured for use in lwipopts.h */
#include "lwip/def.h"
#include "lwip/mem.h"
#include "lwip/netif.h"
#include "lwip/ip.h"
#include "lwip/ip6.h"
#include "lwip/ip6_addr.h"
#include "lwip/ip6_frag.h"
#include "lwip/icmp6.h"
#include "lwip/raw.h"
#include "lwip/udp.h"
#include "lwip/priv/tcp_priv.h"
#include "lwip/dhcp6.h"
#include "lwip/nd6.h"
#include "lwip/mld6.h"
#include "lwip/debug.h"
#include "lwip/stats.h"
#ifdef LWIP_HOOK_FILENAME
#include LWIP_HOOK_FILENAME
#endif
/**
* Finds the appropriate network interface for a given IPv6 address. It tries to select
* a netif following a sequence of heuristics:
* 1) if there is only 1 netif, return it
* 2) if the destination is a link-local address, try to match the src address to a netif.
* this is a tricky case because with multiple netifs, link-local addresses only have
* meaning within a particular subnet/link.
* 3) tries to match the destination subnet to a configured address
* 4) tries to find a router-announced route
* 5) tries to match the source address to the netif
* 6) returns the default netif, if configured
*
* @param src the source IPv6 address, if known
* @param dest the destination IPv6 address for which to find the route
* @return the netif on which to send to reach dest
*/
struct netif *
ip6_route(const ip6_addr_t *src, const ip6_addr_t *dest)
{
struct netif *netif;
s8_t i;
/* If single netif configuration, fast return. */
if ((netif_list != NULL) && (netif_list->next == NULL)) {
if (!netif_is_up(netif_list) || !netif_is_link_up(netif_list)) {
return NULL;
}
return netif_list;
}
/* Special processing for link-local addresses. */
if (ip6_addr_islinklocal(dest)) {
if (ip6_addr_isany(src)) {
/* Use default netif, if Up. */
if (netif_default == NULL || !netif_is_up(netif_default) ||
!netif_is_link_up(netif_default)) {
return NULL;
}
return netif_default;
}
/* Try to find the netif for the source address, checking that link is up. */
for (netif = netif_list; netif != NULL; netif = netif->next) {
if (!netif_is_up(netif) || !netif_is_link_up(netif)) {
continue;
}
for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
if (ip6_addr_isvalid(netif_ip6_addr_state(netif, i)) &&
ip6_addr_cmp(src, netif_ip6_addr(netif, i))) {
return netif;
}
}
}
/* netif not found, use default netif, if up */
if (netif_default == NULL || !netif_is_up(netif_default) ||
!netif_is_link_up(netif_default)) {
return NULL;
}
return netif_default;
}
/* we come here for non-link-local addresses */
#ifdef LWIP_HOOK_IP6_ROUTE
netif = LWIP_HOOK_IP6_ROUTE(src, dest);
if (netif != NULL) {
return netif;
}
#endif
/* See if the destination subnet matches a configured address. In accordance
* with RFC 5942, dynamically configured addresses do not have an implied
* local subnet, and thus should be considered /128 assignments. However, as
* such, the destination address may still match a local address, and so we
* still need to check for exact matches here. By (lwIP) policy, statically
* configured addresses do always have an implied local /64 subnet. */
for (netif = netif_list; netif != NULL; netif = netif->next) {
if (!netif_is_up(netif) || !netif_is_link_up(netif)) {
continue;
}
for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
if (ip6_addr_isvalid(netif_ip6_addr_state(netif, i)) &&
ip6_addr_netcmp(dest, netif_ip6_addr(netif, i)) &&
(netif_ip6_addr_isstatic(netif, i) ||
ip6_addr_nethostcmp(dest, netif_ip6_addr(netif, i)))) {
return netif;
}
}
}
/* Get the netif for a suitable router-announced route. */
netif = nd6_find_route(dest);
if (netif != NULL) {
return netif;
}
/* try with the netif that matches the source address. */
if (!ip6_addr_isany(src)) {
for (netif = netif_list; netif != NULL; netif = netif->next) {
if (!netif_is_up(netif) || !netif_is_link_up(netif)) {
continue;
}
for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
if (ip6_addr_isvalid(netif_ip6_addr_state(netif, i)) &&
ip6_addr_cmp(src, netif_ip6_addr(netif, i))) {
return netif;
}
}
}
}
#if LWIP_NETIF_LOOPBACK && !LWIP_HAVE_LOOPIF
/* loopif is disabled, loopback traffic is passed through any netif */
if (ip6_addr_isloopback(dest)) {
/* don't check for link on loopback traffic */
if (netif_default != NULL && netif_is_up(netif_default)) {
return netif_default;
}
/* default netif is not up, just use any netif for loopback traffic */
for (netif = netif_list; netif != NULL; netif = netif->next) {
if (netif_is_up(netif)) {
return netif;
}
}
return NULL;
}
#endif /* LWIP_NETIF_LOOPBACK && !LWIP_HAVE_LOOPIF */
/* no matching netif found, use default netif, if up */
if ((netif_default == NULL) || !netif_is_up(netif_default) || !netif_is_link_up(netif_default)) {
return NULL;
}
return netif_default;
}
/**
* @ingroup ip6
* Select the best IPv6 source address for a given destination IPv6 address.
*
* This implementation follows RFC 6724 Sec. 5 to the following extent:
* - Rules 1, 2, 3: fully implemented
* - Rules 4, 5, 5.5: not applicable
* - Rule 6: not implemented
* - Rule 7: not applicable
* - Rule 8: limited to "prefer /64 subnet match over non-match"
*
* For Rule 2, we deliberately deviate from RFC 6724 Sec. 3.1 by considering
* ULAs to be of smaller scope than global addresses, to avoid that a preferred
* ULA is picked over a deprecated global address when given a global address
* as destination, as that would likely result in broken two-way communication.
*
* As long as temporary addresses are not supported (as used in Rule 7), a
* proper implementation of Rule 8 would obviate the need to implement Rule 6.
*
* @param netif the netif on which to send a packet
* @param dest the destination we are trying to reach
* @return the most suitable source address to use, or NULL if no suitable
* source address is found
*/
const ip_addr_t *
ip6_select_source_address(struct netif *netif, const ip6_addr_t *dest)
{
const ip_addr_t *best_addr;
const ip6_addr_t *cand_addr;
s8_t dest_scope, cand_scope;
s8_t best_scope = IP6_MULTICAST_SCOPE_RESERVED;
u8_t i, cand_pref, cand_bits;
u8_t best_pref = 0;
u8_t best_bits = 0;
/* Start by determining the scope of the given destination address. These
* tests are hopefully (roughly) in order of likeliness to match. */
if (ip6_addr_isglobal(dest)) {
dest_scope = IP6_MULTICAST_SCOPE_GLOBAL;
} else if (ip6_addr_islinklocal(dest) || ip6_addr_isloopback(dest)) {
dest_scope = IP6_MULTICAST_SCOPE_LINK_LOCAL;
} else if (ip6_addr_isuniquelocal(dest)) {
dest_scope = IP6_MULTICAST_SCOPE_ORGANIZATION_LOCAL;
} else if (ip6_addr_ismulticast(dest)) {
dest_scope = ip6_addr_multicast_scope(dest);
} else if (ip6_addr_issitelocal(dest)) {
dest_scope = IP6_MULTICAST_SCOPE_SITE_LOCAL;
} else {
/* no match, consider scope global */
dest_scope = IP6_MULTICAST_SCOPE_GLOBAL;
}
best_addr = NULL;
for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
/* Consider only valid (= preferred and deprecated) addresses. */
if (!ip6_addr_isvalid(netif_ip6_addr_state(netif, i))) {
continue;
}
/* Determine the scope of this candidate address. Same ordering idea. */
cand_addr = netif_ip6_addr(netif, i);
if (ip6_addr_isglobal(cand_addr)) {
cand_scope = IP6_MULTICAST_SCOPE_GLOBAL;
} else if (ip6_addr_islinklocal(cand_addr)) {
cand_scope = IP6_MULTICAST_SCOPE_LINK_LOCAL;
} else if (ip6_addr_isuniquelocal(cand_addr)) {
cand_scope = IP6_MULTICAST_SCOPE_ORGANIZATION_LOCAL;
} else if (ip6_addr_issitelocal(cand_addr)) {
cand_scope = IP6_MULTICAST_SCOPE_SITE_LOCAL;
} else {
/* no match, treat as low-priority global scope */
cand_scope = IP6_MULTICAST_SCOPE_RESERVEDF;
}
cand_pref = ip6_addr_ispreferred(netif_ip6_addr_state(netif, i));
/* @todo compute the actual common bits, for longest matching prefix. */
cand_bits = ip6_addr_netcmp(cand_addr, dest); /* just 1 or 0 for now */
if (cand_bits && ip6_addr_nethostcmp(cand_addr, dest)) {
return netif_ip_addr6(netif, i); /* Rule 1 */
}
if ((best_addr == NULL) || /* no alternative yet */
((cand_scope < best_scope) && (cand_scope >= dest_scope)) ||
((cand_scope > best_scope) && (best_scope < dest_scope)) || /* Rule 2 */
((cand_scope == best_scope) && ((cand_pref > best_pref) || /* Rule 3 */
((cand_pref == best_pref) && (cand_bits > best_bits))))) { /* Rule 8 */
/* We found a new "winning" candidate. */
best_addr = netif_ip_addr6(netif, i);
best_scope = cand_scope;
best_pref = cand_pref;
best_bits = cand_bits;
}
}
return best_addr; /* may be NULL */
}
#if LWIP_IPV6_FORWARD
/**
* Forwards an IPv6 packet. It finds an appropriate route for the
* packet, decrements the HL value of the packet, and outputs
* the packet on the appropriate interface.
*
* @param p the packet to forward (p->payload points to IP header)
* @param iphdr the IPv6 header of the input packet
* @param inp the netif on which this packet was received
*/
static void
ip6_forward(struct pbuf *p, struct ip6_hdr *iphdr, struct netif *inp)
{
struct netif *netif;
/* do not forward link-local or loopback addresses */
if (ip6_addr_islinklocal(ip6_current_dest_addr()) ||
ip6_addr_isloopback(ip6_current_dest_addr())) {
LWIP_DEBUGF(IP6_DEBUG, ("ip6_forward: not forwarding link-local address.\n"));
IP6_STATS_INC(ip6.rterr);
IP6_STATS_INC(ip6.drop);
return;
}
/* Find network interface where to forward this IP packet to. */
netif = ip6_route(IP6_ADDR_ANY6, ip6_current_dest_addr());
if (netif == NULL) {
LWIP_DEBUGF(IP6_DEBUG, ("ip6_forward: no route for %"X16_F":%"X16_F":%"X16_F":%"X16_F":%"X16_F":%"X16_F":%"X16_F":%"X16_F"\n",
IP6_ADDR_BLOCK1(ip6_current_dest_addr()),
IP6_ADDR_BLOCK2(ip6_current_dest_addr()),
IP6_ADDR_BLOCK3(ip6_current_dest_addr()),
IP6_ADDR_BLOCK4(ip6_current_dest_addr()),
IP6_ADDR_BLOCK5(ip6_current_dest_addr()),
IP6_ADDR_BLOCK6(ip6_current_dest_addr()),
IP6_ADDR_BLOCK7(ip6_current_dest_addr()),
IP6_ADDR_BLOCK8(ip6_current_dest_addr())));
#if LWIP_ICMP6
/* Don't send ICMP messages in response to ICMP messages */
if (IP6H_NEXTH(iphdr) != IP6_NEXTH_ICMP6) {
icmp6_dest_unreach(p, ICMP6_DUR_NO_ROUTE);
}
#endif /* LWIP_ICMP6 */
IP6_STATS_INC(ip6.rterr);
IP6_STATS_INC(ip6.drop);
return;
}
/* Do not forward packets onto the same network interface on which
* they arrived. */
if (netif == inp) {
LWIP_DEBUGF(IP6_DEBUG, ("ip6_forward: not bouncing packets back on incoming interface.\n"));
IP6_STATS_INC(ip6.rterr);
IP6_STATS_INC(ip6.drop);
return;
}
/* decrement HL */
IP6H_HOPLIM_SET(iphdr, IP6H_HOPLIM(iphdr) - 1);
/* send ICMP6 if HL == 0 */
if (IP6H_HOPLIM(iphdr) == 0) {
#if LWIP_ICMP6
/* Don't send ICMP messages in response to ICMP messages */
if (IP6H_NEXTH(iphdr) != IP6_NEXTH_ICMP6) {
icmp6_time_exceeded(p, ICMP6_TE_HL);
}
#endif /* LWIP_ICMP6 */
IP6_STATS_INC(ip6.drop);
return;
}
if (netif->mtu && (p->tot_len > netif->mtu)) {
#if LWIP_ICMP6
/* Don't send ICMP messages in response to ICMP messages */
if (IP6H_NEXTH(iphdr) != IP6_NEXTH_ICMP6) {
icmp6_packet_too_big(p, netif->mtu);
}
#endif /* LWIP_ICMP6 */
IP6_STATS_INC(ip6.drop);
return;
}
LWIP_DEBUGF(IP6_DEBUG, ("ip6_forward: forwarding packet to %"X16_F":%"X16_F":%"X16_F":%"X16_F":%"X16_F":%"X16_F":%"X16_F":%"X16_F"\n",
IP6_ADDR_BLOCK1(ip6_current_dest_addr()),
IP6_ADDR_BLOCK2(ip6_current_dest_addr()),
IP6_ADDR_BLOCK3(ip6_current_dest_addr()),
IP6_ADDR_BLOCK4(ip6_current_dest_addr()),
IP6_ADDR_BLOCK5(ip6_current_dest_addr()),
IP6_ADDR_BLOCK6(ip6_current_dest_addr()),
IP6_ADDR_BLOCK7(ip6_current_dest_addr()),
IP6_ADDR_BLOCK8(ip6_current_dest_addr())));
/* transmit pbuf on chosen interface */
netif->output_ip6(netif, p, ip6_current_dest_addr());
IP6_STATS_INC(ip6.fw);
IP6_STATS_INC(ip6.xmit);
return;
}
#endif /* LWIP_IPV6_FORWARD */
/**
* This function is called by the network interface device driver when
* an IPv6 packet is received. The function does the basic checks of the
* IP header such as packet size being at least larger than the header
* size etc. If the packet was not destined for us, the packet is
* forwarded (using ip6_forward).
*
* Finally, the packet is sent to the upper layer protocol input function.
*
* @param p the received IPv6 packet (p->payload points to IPv6 header)
* @param inp the netif on which this packet was received
* @return ERR_OK if the packet was processed (could return ERR_* if it wasn't
* processed, but currently always returns ERR_OK)
*/
err_t
ip6_input(struct pbuf *p, struct netif *inp)
{
struct ip6_hdr *ip6hdr;
struct netif *netif;
u8_t nexth;
u16_t hlen; /* the current header length */
u8_t i;
#if 0 /*IP_ACCEPT_LINK_LAYER_ADDRESSING*/
@todo
int check_ip_src=1;
#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
IP6_STATS_INC(ip6.recv);
/* identify the IP header */
ip6hdr = (struct ip6_hdr *)p->payload;
if (IP6H_V(ip6hdr) != 6) {
LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_WARNING, ("IPv6 packet dropped due to bad version number %"U32_F"\n",
IP6H_V(ip6hdr)));
pbuf_free(p);
IP6_STATS_INC(ip6.err);
IP6_STATS_INC(ip6.drop);
return ERR_OK;
}
#ifdef LWIP_HOOK_IP6_INPUT
if (LWIP_HOOK_IP6_INPUT(p, inp)) {
/* the packet has been eaten */
return ERR_OK;
}
#endif
/* header length exceeds first pbuf length, or ip length exceeds total pbuf length? */
if ((IP6_HLEN > p->len) || ((IP6H_PLEN(ip6hdr) + IP6_HLEN) > p->tot_len)) {
if (IP6_HLEN > p->len) {
LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
("IPv6 header (len %"U16_F") does not fit in first pbuf (len %"U16_F"), IP packet dropped.\n",
(u16_t)IP6_HLEN, p->len));
}
if ((IP6H_PLEN(ip6hdr) + IP6_HLEN) > p->tot_len) {
LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
("IPv6 (plen %"U16_F") is longer than pbuf (len %"U16_F"), IP packet dropped.\n",
(u16_t)(IP6H_PLEN(ip6hdr) + IP6_HLEN), p->tot_len));
}
/* free (drop) packet pbufs */
pbuf_free(p);
IP6_STATS_INC(ip6.lenerr);
IP6_STATS_INC(ip6.drop);
return ERR_OK;
}
/* Trim pbuf. This should have been done at the netif layer,
* but we'll do it anyway just to be sure that its done. */
pbuf_realloc(p, IP6_HLEN + IP6H_PLEN(ip6hdr));
/* copy IP addresses to aligned ip6_addr_t */
ip_addr_copy_from_ip6(ip_data.current_iphdr_dest, ip6hdr->dest);
ip_addr_copy_from_ip6(ip_data.current_iphdr_src, ip6hdr->src);
/* Don't accept virtual IPv4 mapped IPv6 addresses.
* Don't accept multicast source addresses. */
if (ip6_addr_isipv4mappedipv6(ip_2_ip6(&ip_data.current_iphdr_dest)) ||
ip6_addr_isipv4mappedipv6(ip_2_ip6(&ip_data.current_iphdr_src)) ||
ip6_addr_ismulticast(ip_2_ip6(&ip_data.current_iphdr_src))) {
IP6_STATS_INC(ip6.err);
IP6_STATS_INC(ip6.drop);
return ERR_OK;
}
/* current header pointer. */
ip_data.current_ip6_header = ip6hdr;
/* In netif, used in case we need to send ICMPv6 packets back. */
ip_data.current_netif = inp;
ip_data.current_input_netif = inp;
/* match packet against an interface, i.e. is this packet for us? */
if (ip6_addr_ismulticast(ip6_current_dest_addr())) {
/* Always joined to multicast if-local and link-local all-nodes group. */
if (ip6_addr_isallnodes_iflocal(ip6_current_dest_addr()) ||
ip6_addr_isallnodes_linklocal(ip6_current_dest_addr())) {
netif = inp;
}
#if LWIP_IPV6_MLD
else if (mld6_lookfor_group(inp, ip6_current_dest_addr())) {
netif = inp;
}
#else /* LWIP_IPV6_MLD */
else if (ip6_addr_issolicitednode(ip6_current_dest_addr())) {
/* Filter solicited node packets when MLD is not enabled
* (for Neighbor discovery). */
netif = NULL;
for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
if (ip6_addr_isvalid(netif_ip6_addr_state(inp, i)) &&
ip6_addr_cmp_solicitednode(ip6_current_dest_addr(), netif_ip6_addr(inp, i))) {
netif = inp;
LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: solicited node packet accepted on interface %c%c\n",
netif->name[0], netif->name[1]));
break;
}
}
}
#endif /* LWIP_IPV6_MLD */
else {
netif = NULL;
}
} else {
/* start trying with inp. if that's not acceptable, start walking the
list of configured netifs.
'first' is used as a boolean to mark whether we started walking the list */
int first = 1;
netif = inp;
do {
/* interface is up? */
if (netif_is_up(netif)) {
/* unicast to this interface address? address configured? */
for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
if (ip6_addr_isvalid(netif_ip6_addr_state(netif, i)) &&
ip6_addr_cmp(ip6_current_dest_addr(), netif_ip6_addr(netif, i))) {
/* exit outer loop */
goto netif_found;
}
}
}
if (first) {
if (ip6_addr_islinklocal(ip6_current_dest_addr())
#if !LWIP_NETIF_LOOPBACK || LWIP_HAVE_LOOPIF
|| ip6_addr_isloopback(ip6_current_dest_addr())
#endif /* !LWIP_NETIF_LOOPBACK || LWIP_HAVE_LOOPIF */
) {
/* Do not match link-local addresses to other netifs. The loopback
* address is to be considered link-local and packets to it should be
* dropped on other interfaces, as per RFC 4291 Sec. 2.5.3. This
* requirement cannot be implemented in the case that loopback
* traffic is sent across a non-loopback interface, however.
*/
netif = NULL;
break;
}
first = 0;
netif = netif_list;
} else {
netif = netif->next;
}
if (netif == inp) {
netif = netif->next;
}
} while (netif != NULL);
netif_found:
LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: packet accepted on interface %c%c\n",
netif ? netif->name[0] : 'X', netif? netif->name[1] : 'X'));
}
/* "::" packet source address? (used in duplicate address detection) */
if (ip6_addr_isany(ip6_current_src_addr()) &&
(!ip6_addr_issolicitednode(ip6_current_dest_addr()))) {
/* packet source is not valid */
/* free (drop) packet pbufs */
LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: packet with src ANY_ADDRESS dropped\n"));
pbuf_free(p);
IP6_STATS_INC(ip6.drop);
goto ip6_input_cleanup;
}
/* packet not for us? */
if (netif == NULL) {
/* packet not for us, route or discard */
LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_TRACE, ("ip6_input: packet not for us.\n"));
#if LWIP_IPV6_FORWARD
/* non-multicast packet? */
if (!ip6_addr_ismulticast(ip6_current_dest_addr())) {
/* try to forward IP packet on (other) interfaces */
ip6_forward(p, ip6hdr, inp);
}
#endif /* LWIP_IPV6_FORWARD */
pbuf_free(p);
goto ip6_input_cleanup;
}
/* current netif pointer. */
ip_data.current_netif = netif;
/* Save next header type. */
nexth = IP6H_NEXTH(ip6hdr);
/* Init header length. */
hlen = ip_data.current_ip_header_tot_len = IP6_HLEN;
/* Move to payload. */
pbuf_header(p, -IP6_HLEN);
/* Process known option extension headers, if present. */
while (nexth != IP6_NEXTH_NONE)
{
switch (nexth) {
case IP6_NEXTH_HOPBYHOP:
LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: packet with Hop-by-Hop options header\n"));
/* Get next header type. */
nexth = *((u8_t *)p->payload);
/* Get the header length. */
hlen = 8 * (1 + *((u8_t *)p->payload + 1));
ip_data.current_ip_header_tot_len += hlen;
/* Skip over this header. */
if (hlen > p->len) {
LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
("IPv6 options header (hlen %"U16_F") does not fit in first pbuf (len %"U16_F"), IPv6 packet dropped.\n",
hlen, p->len));
/* free (drop) packet pbufs */
pbuf_free(p);
IP6_STATS_INC(ip6.lenerr);
IP6_STATS_INC(ip6.drop);
goto ip6_input_cleanup;
}
pbuf_header(p, -(s16_t)hlen);
break;
case IP6_NEXTH_DESTOPTS:
LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: packet with Destination options header\n"));
/* Get next header type. */
nexth = *((u8_t *)p->payload);
/* Get the header length. */
hlen = 8 * (1 + *((u8_t *)p->payload + 1));
ip_data.current_ip_header_tot_len += hlen;
/* Skip over this header. */
if (hlen > p->len) {
LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
("IPv6 options header (hlen %"U16_F") does not fit in first pbuf (len %"U16_F"), IPv6 packet dropped.\n",
hlen, p->len));
/* free (drop) packet pbufs */
pbuf_free(p);
IP6_STATS_INC(ip6.lenerr);
IP6_STATS_INC(ip6.drop);
goto ip6_input_cleanup;
}
pbuf_header(p, -(s16_t)hlen);
break;
case IP6_NEXTH_ROUTING:
LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: packet with Routing header\n"));
/* Get next header type. */
nexth = *((u8_t *)p->payload);
/* Get the header length. */
hlen = 8 * (1 + *((u8_t *)p->payload + 1));
ip_data.current_ip_header_tot_len += hlen;
/* Skip over this header. */
if (hlen > p->len) {
LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
("IPv6 options header (hlen %"U16_F") does not fit in first pbuf (len %"U16_F"), IPv6 packet dropped.\n",
hlen, p->len));
/* free (drop) packet pbufs */
pbuf_free(p);
IP6_STATS_INC(ip6.lenerr);
IP6_STATS_INC(ip6.drop);
goto ip6_input_cleanup;
}
pbuf_header(p, -(s16_t)hlen);
break;
case IP6_NEXTH_FRAGMENT:
{
struct ip6_frag_hdr *frag_hdr;
LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: packet with Fragment header\n"));
frag_hdr = (struct ip6_frag_hdr *)p->payload;
/* Get next header type. */
nexth = frag_hdr->_nexth;
/* Fragment Header length. */
hlen = 8;
ip_data.current_ip_header_tot_len += hlen;
/* Make sure this header fits in current pbuf. */
if (hlen > p->len) {
LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
("IPv6 options header (hlen %"U16_F") does not fit in first pbuf (len %"U16_F"), IPv6 packet dropped.\n",
hlen, p->len));
/* free (drop) packet pbufs */
pbuf_free(p);
IP6_FRAG_STATS_INC(ip6_frag.lenerr);
IP6_FRAG_STATS_INC(ip6_frag.drop);
goto ip6_input_cleanup;
}
/* Offset == 0 and more_fragments == 0? */
if ((frag_hdr->_fragment_offset &
PP_HTONS(IP6_FRAG_OFFSET_MASK | IP6_FRAG_MORE_FLAG)) == 0) {
/* This is a 1-fragment packet, usually a packet that we have
* already reassembled. Skip this header anc continue. */
pbuf_header(p, -(s16_t)hlen);
} else {
#if LWIP_IPV6_REASS
/* reassemble the packet */
p = ip6_reass(p);
/* packet not fully reassembled yet? */
if (p == NULL) {
goto ip6_input_cleanup;
}
/* Returned p point to IPv6 header.
* Update all our variables and pointers and continue. */
ip6hdr = (struct ip6_hdr *)p->payload;
nexth = IP6H_NEXTH(ip6hdr);
hlen = ip_data.current_ip_header_tot_len = IP6_HLEN;
pbuf_header(p, -IP6_HLEN);
#else /* LWIP_IPV6_REASS */
/* free (drop) packet pbufs */
LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: packet with Fragment header dropped (with LWIP_IPV6_REASS==0)\n"));
pbuf_free(p);
IP6_STATS_INC(ip6.opterr);
IP6_STATS_INC(ip6.drop);
goto ip6_input_cleanup;
#endif /* LWIP_IPV6_REASS */
}
break;
}
default:
goto options_done;
break;
}
}
options_done:
/* p points to IPv6 header again. */
pbuf_header_force(p, (s16_t)ip_data.current_ip_header_tot_len);
/* send to upper layers */
LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: \n"));
ip6_debug_print(p);
LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: p->len %"U16_F" p->tot_len %"U16_F"\n", p->len, p->tot_len));
#if LWIP_RAW
/* raw input did not eat the packet? */
if (raw_input(p, inp) == 0)
#endif /* LWIP_RAW */
{
switch (nexth) {
case IP6_NEXTH_NONE:
pbuf_free(p);
break;
#if LWIP_UDP
case IP6_NEXTH_UDP:
#if LWIP_UDPLITE
case IP6_NEXTH_UDPLITE:
#endif /* LWIP_UDPLITE */
/* Point to payload. */
pbuf_header(p, -(s16_t)ip_data.current_ip_header_tot_len);
udp_input(p, inp);
break;
#endif /* LWIP_UDP */
#if LWIP_TCP
case IP6_NEXTH_TCP:
/* Point to payload. */
pbuf_header(p, -(s16_t)ip_data.current_ip_header_tot_len);
tcp_input(p, inp);
break;
#endif /* LWIP_TCP */
#if LWIP_ICMP6
case IP6_NEXTH_ICMP6:
/* Point to payload. */
pbuf_header(p, -(s16_t)ip_data.current_ip_header_tot_len);
icmp6_input(p, inp);
break;
#endif /* LWIP_ICMP */
default:
#if LWIP_ICMP6
/* send ICMP parameter problem unless it was a multicast or ICMPv6 */
if ((!ip6_addr_ismulticast(ip6_current_dest_addr())) &&
(IP6H_NEXTH(ip6hdr) != IP6_NEXTH_ICMP6)) {
icmp6_param_problem(p, ICMP6_PP_HEADER, ip_data.current_ip_header_tot_len - hlen);
}
#endif /* LWIP_ICMP */
LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip6_input: Unsupported transport protocol %"U16_F"\n", (u16_t)IP6H_NEXTH(ip6hdr)));
pbuf_free(p);
IP6_STATS_INC(ip6.proterr);
IP6_STATS_INC(ip6.drop);
break;
}
}
ip6_input_cleanup:
ip_data.current_netif = NULL;
ip_data.current_input_netif = NULL;
ip_data.current_ip6_header = NULL;
ip_data.current_ip_header_tot_len = 0;
ip6_addr_set_zero(ip6_current_src_addr());
ip6_addr_set_zero(ip6_current_dest_addr());
return ERR_OK;
}
/**
* Sends an IPv6 packet on a network interface. This function constructs
* the IPv6 header. If the source IPv6 address is NULL, the IPv6 "ANY" address is
* used as source (usually during network startup). If the source IPv6 address it
* IP6_ADDR_ANY, the most appropriate IPv6 address of the outgoing network
* interface is filled in as source address. If the destination IPv6 address is
* LWIP_IP_HDRINCL, p is assumed to already include an IPv6 header and
* p->payload points to it instead of the data.
*
* @param p the packet to send (p->payload points to the data, e.g. next
protocol header; if dest == LWIP_IP_HDRINCL, p already includes an
IPv6 header and p->payload points to that IPv6 header)
* @param src the source IPv6 address to send from (if src == IP6_ADDR_ANY, an
* IP address of the netif is selected and used as source address.
* if src == NULL, IP6_ADDR_ANY is used as source)
* @param dest the destination IPv6 address to send the packet to
* @param hl the Hop Limit value to be set in the IPv6 header
* @param tc the Traffic Class value to be set in the IPv6 header
* @param nexth the Next Header to be set in the IPv6 header
* @param netif the netif on which to send this packet
* @return ERR_OK if the packet was sent OK
* ERR_BUF if p doesn't have enough space for IPv6/LINK headers
* returns errors returned by netif->output
*/
err_t
ip6_output_if(struct pbuf *p, const ip6_addr_t *src, const ip6_addr_t *dest,
u8_t hl, u8_t tc,
u8_t nexth, struct netif *netif)
{
const ip6_addr_t *src_used = src;
if (dest != LWIP_IP_HDRINCL) {
if (src != NULL && ip6_addr_isany(src)) {
src_used = ip_2_ip6(ip6_select_source_address(netif, dest));
if ((src_used == NULL) || ip6_addr_isany(src_used)) {
/* No appropriate source address was found for this packet. */
LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip6_output: No suitable source address for packet.\n"));
IP6_STATS_INC(ip6.rterr);
return ERR_RTE;
}
}
}
return ip6_output_if_src(p, src_used, dest, hl, tc, nexth, netif);
}
/**
* Same as ip6_output_if() but 'src' address is not replaced by netif address
* when it is 'any'.
*/
err_t
ip6_output_if_src(struct pbuf *p, const ip6_addr_t *src, const ip6_addr_t *dest,
u8_t hl, u8_t tc,
u8_t nexth, struct netif *netif)
{
struct ip6_hdr *ip6hdr;
ip6_addr_t dest_addr;
LWIP_IP_CHECK_PBUF_REF_COUNT_FOR_TX(p);
/* Should the IPv6 header be generated or is it already included in p? */
if (dest != LWIP_IP_HDRINCL) {
/* generate IPv6 header */
if (pbuf_header(p, IP6_HLEN)) {
LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip6_output: not enough room for IPv6 header in pbuf\n"));
IP6_STATS_INC(ip6.err);
return ERR_BUF;
}
ip6hdr = (struct ip6_hdr *)p->payload;
LWIP_ASSERT("check that first pbuf can hold struct ip6_hdr",
(p->len >= sizeof(struct ip6_hdr)));
IP6H_HOPLIM_SET(ip6hdr, hl);
IP6H_NEXTH_SET(ip6hdr, nexth);
/* dest cannot be NULL here */
ip6_addr_copy(ip6hdr->dest, *dest);
IP6H_VTCFL_SET(ip6hdr, 6, tc, 0);
IP6H_PLEN_SET(ip6hdr, p->tot_len - IP6_HLEN);
if (src == NULL) {
src = IP6_ADDR_ANY6;
}
/* src cannot be NULL here */
ip6_addr_copy(ip6hdr->src, *src);
} else {
/* IP header already included in p */
ip6hdr = (struct ip6_hdr *)p->payload;
ip6_addr_copy(dest_addr, ip6hdr->dest);
dest = &dest_addr;
}
IP6_STATS_INC(ip6.xmit);
LWIP_DEBUGF(IP6_DEBUG, ("ip6_output_if: %c%c%"U16_F"\n", netif->name[0], netif->name[1], (u16_t)netif->num));
ip6_debug_print(p);
#if ENABLE_LOOPBACK
{
int i;
#if !LWIP_HAVE_LOOPIF
if (ip6_addr_isloopback(dest)) {
return netif_loop_output(netif, p);
}
#endif /* !LWIP_HAVE_LOOPIF */
for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
if (ip6_addr_isvalid(netif_ip6_addr_state(netif, i)) &&
ip6_addr_cmp(dest, netif_ip6_addr(netif, i))) {
/* Packet to self, enqueue it for loopback */
LWIP_DEBUGF(IP6_DEBUG, ("netif_loop_output()\n"));
return netif_loop_output(netif, p);
}
}
}
#endif /* ENABLE_LOOPBACK */
#if LWIP_IPV6_FRAG
/* don't fragment if interface has mtu set to 0 [loopif] */
if (netif->mtu && (p->tot_len > nd6_get_destination_mtu(dest, netif))) {
return ip6_frag(p, netif, dest);
}
#endif /* LWIP_IPV6_FRAG */
LWIP_DEBUGF(IP6_DEBUG, ("netif->output_ip6()\n"));
return netif->output_ip6(netif, p, dest);
}
/**
* Simple interface to ip6_output_if. It finds the outgoing network
* interface and calls upon ip6_output_if to do the actual work.
*
* @param p the packet to send (p->payload points to the data, e.g. next
protocol header; if dest == LWIP_IP_HDRINCL, p already includes an
IPv6 header and p->payload points to that IPv6 header)
* @param src the source IPv6 address to send from (if src == IP6_ADDR_ANY, an
* IP address of the netif is selected and used as source address.
* if src == NULL, IP6_ADDR_ANY is used as source)
* @param dest the destination IPv6 address to send the packet to
* @param hl the Hop Limit value to be set in the IPv6 header
* @param tc the Traffic Class value to be set in the IPv6 header
* @param nexth the Next Header to be set in the IPv6 header
*
* @return ERR_RTE if no route is found
* see ip_output_if() for more return values
*/
err_t
ip6_output(struct pbuf *p, const ip6_addr_t *src, const ip6_addr_t *dest,
u8_t hl, u8_t tc, u8_t nexth)
{
struct netif *netif;
struct ip6_hdr *ip6hdr;
ip6_addr_t src_addr, dest_addr;
LWIP_IP_CHECK_PBUF_REF_COUNT_FOR_TX(p);
if (dest != LWIP_IP_HDRINCL) {
netif = ip6_route(src, dest);
} else {
/* IP header included in p, read addresses. */
ip6hdr = (struct ip6_hdr *)p->payload;
ip6_addr_copy(src_addr, ip6hdr->src);
ip6_addr_copy(dest_addr, ip6hdr->dest);
netif = ip6_route(&src_addr, &dest_addr);
}
if (netif == NULL) {
LWIP_DEBUGF(IP6_DEBUG, ("ip6_output: no route for %"X16_F":%"X16_F":%"X16_F":%"X16_F":%"X16_F":%"X16_F":%"X16_F":%"X16_F"\n",
IP6_ADDR_BLOCK1(dest),
IP6_ADDR_BLOCK2(dest),
IP6_ADDR_BLOCK3(dest),
IP6_ADDR_BLOCK4(dest),
IP6_ADDR_BLOCK5(dest),
IP6_ADDR_BLOCK6(dest),
IP6_ADDR_BLOCK7(dest),
IP6_ADDR_BLOCK8(dest)));
IP6_STATS_INC(ip6.rterr);
return ERR_RTE;
}
return ip6_output_if(p, src, dest, hl, tc, nexth, netif);
}
#if LWIP_NETIF_HWADDRHINT
/** Like ip6_output, but takes and addr_hint pointer that is passed on to netif->addr_hint
* before calling ip6_output_if.
*
* @param p the packet to send (p->payload points to the data, e.g. next
protocol header; if dest == LWIP_IP_HDRINCL, p already includes an
IPv6 header and p->payload points to that IPv6 header)
* @param src the source IPv6 address to send from (if src == IP6_ADDR_ANY, an
* IP address of the netif is selected and used as source address.
* if src == NULL, IP6_ADDR_ANY is used as source)
* @param dest the destination IPv6 address to send the packet to
* @param hl the Hop Limit value to be set in the IPv6 header
* @param tc the Traffic Class value to be set in the IPv6 header
* @param nexth the Next Header to be set in the IPv6 header
* @param addr_hint address hint pointer set to netif->addr_hint before
* calling ip_output_if()
*
* @return ERR_RTE if no route is found
* see ip_output_if() for more return values
*/
err_t
ip6_output_hinted(struct pbuf *p, const ip6_addr_t *src, const ip6_addr_t *dest,
u8_t hl, u8_t tc, u8_t nexth, u8_t *addr_hint)
{
struct netif *netif;
struct ip6_hdr *ip6hdr;
ip6_addr_t src_addr, dest_addr;
err_t err;
LWIP_IP_CHECK_PBUF_REF_COUNT_FOR_TX(p);
if (dest != LWIP_IP_HDRINCL) {
netif = ip6_route(src, dest);
} else {
/* IP header included in p, read addresses. */
ip6hdr = (struct ip6_hdr *)p->payload;
ip6_addr_copy(src_addr, ip6hdr->src);
ip6_addr_copy(dest_addr, ip6hdr->dest);
netif = ip6_route(&src_addr, &dest_addr);
}
if (netif == NULL) {
LWIP_DEBUGF(IP6_DEBUG, ("ip6_output: no route for %"X16_F":%"X16_F":%"X16_F":%"X16_F":%"X16_F":%"X16_F":%"X16_F":%"X16_F"\n",
IP6_ADDR_BLOCK1(dest),
IP6_ADDR_BLOCK2(dest),
IP6_ADDR_BLOCK3(dest),
IP6_ADDR_BLOCK4(dest),
IP6_ADDR_BLOCK5(dest),
IP6_ADDR_BLOCK6(dest),
IP6_ADDR_BLOCK7(dest),
IP6_ADDR_BLOCK8(dest)));
IP6_STATS_INC(ip6.rterr);
return ERR_RTE;
}
NETIF_SET_HWADDRHINT(netif, addr_hint);
err = ip6_output_if(p, src, dest, hl, tc, nexth, netif);
NETIF_SET_HWADDRHINT(netif, NULL);
return err;
}
#endif /* LWIP_NETIF_HWADDRHINT*/
#if LWIP_IPV6_MLD
/**
* Add a hop-by-hop options header with a router alert option and padding.
*
* Used by MLD when sending a Multicast listener report/done message.
*
* @param p the packet to which we will prepend the options header
* @param nexth the next header protocol number (e.g. IP6_NEXTH_ICMP6)
* @param value the value of the router alert option data (e.g. IP6_ROUTER_ALERT_VALUE_MLD)
* @return ERR_OK if hop-by-hop header was added, ERR_* otherwise
*/
err_t
ip6_options_add_hbh_ra(struct pbuf *p, u8_t nexth, u8_t value)
{
struct ip6_hbh_hdr *hbh_hdr;
/* Move pointer to make room for hop-by-hop options header. */
if (pbuf_header(p, sizeof(struct ip6_hbh_hdr))) {
LWIP_DEBUGF(IP6_DEBUG, ("ip6_options: no space for options header\n"));
IP6_STATS_INC(ip6.err);
return ERR_BUF;
}
hbh_hdr = (struct ip6_hbh_hdr *)p->payload;
/* Set fields. */
hbh_hdr->_nexth = nexth;
hbh_hdr->_hlen = 0;
hbh_hdr->_ra_opt_type = IP6_ROUTER_ALERT_OPTION;
hbh_hdr->_ra_opt_dlen = 2;
hbh_hdr->_ra_opt_data = value;
hbh_hdr->_padn_opt_type = IP6_PADN_ALERT_OPTION;
hbh_hdr->_padn_opt_dlen = 0;
return ERR_OK;
}
#endif /* LWIP_IPV6_MLD */
#if IP6_DEBUG
/* Print an IPv6 header by using LWIP_DEBUGF
* @param p an IPv6 packet, p->payload pointing to the IPv6 header
*/
void
ip6_debug_print(struct pbuf *p)
{
struct ip6_hdr *ip6hdr = (struct ip6_hdr *)p->payload;
TRACE_TO_ASCII_HEX_DUMPF("IP>", IP6H_PLEN(ip6hdr) + 40, (char *) ip6hdr);
LWIP_DEBUGF(IP6_DEBUG, ("IPv6 header:\n"));
LWIP_DEBUGF(IP6_DEBUG, ("+-------------------------------+\n"));
LWIP_DEBUGF(IP6_DEBUG, ("| %2"U16_F" | %3"U16_F" | %7"U32_F" | (ver, class, flow)\n",
IP6H_V(ip6hdr),
IP6H_TC(ip6hdr),
IP6H_FL(ip6hdr)));
LWIP_DEBUGF(IP6_DEBUG, ("+-------------------------------+\n"));
LWIP_DEBUGF(IP6_DEBUG, ("| %5"U16_F" | %3"U16_F" | %3"U16_F" | (plen, nexth, hopl)\n",
IP6H_PLEN(ip6hdr),
IP6H_NEXTH(ip6hdr),
IP6H_HOPLIM(ip6hdr)));
LWIP_DEBUGF(IP6_DEBUG, ("+-------------------------------+\n"));
LWIP_DEBUGF(IP6_DEBUG, ("| %4"X32_F" | %4"X32_F" | %4"X32_F" | %4"X32_F" | (src)\n",
IP6_ADDR_BLOCK1(&(ip6hdr->src)),
IP6_ADDR_BLOCK2(&(ip6hdr->src)),
IP6_ADDR_BLOCK3(&(ip6hdr->src)),
IP6_ADDR_BLOCK4(&(ip6hdr->src))));
LWIP_DEBUGF(IP6_DEBUG, ("| %4"X32_F" | %4"X32_F" | %4"X32_F" | %4"X32_F" |\n",
IP6_ADDR_BLOCK5(&(ip6hdr->src)),
IP6_ADDR_BLOCK6(&(ip6hdr->src)),
IP6_ADDR_BLOCK7(&(ip6hdr->src)),
IP6_ADDR_BLOCK8(&(ip6hdr->src))));
LWIP_DEBUGF(IP6_DEBUG, ("+-------------------------------+\n"));
LWIP_DEBUGF(IP6_DEBUG, ("| %4"X32_F" | %4"X32_F" | %4"X32_F" | %4"X32_F" | (dest)\n",
IP6_ADDR_BLOCK1(&(ip6hdr->dest)),
IP6_ADDR_BLOCK2(&(ip6hdr->dest)),
IP6_ADDR_BLOCK3(&(ip6hdr->dest)),
IP6_ADDR_BLOCK4(&(ip6hdr->dest))));
LWIP_DEBUGF(IP6_DEBUG, ("| %4"X32_F" | %4"X32_F" | %4"X32_F" | %4"X32_F" |\n",
IP6_ADDR_BLOCK5(&(ip6hdr->dest)),
IP6_ADDR_BLOCK6(&(ip6hdr->dest)),
IP6_ADDR_BLOCK7(&(ip6hdr->dest)),
IP6_ADDR_BLOCK8(&(ip6hdr->dest))));
LWIP_DEBUGF(IP6_DEBUG, ("+-------------------------------+\n"));
}
#endif /* IP6_DEBUG */
#endif /* LWIP_IPV6 */
