/**
* 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
* 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 == 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 != IP_HDRINCL) {
if (src != NULL && ip6_addr_isany(src)) {
src = ip_2_ip6(ip6_select_source_address(netif, dest));
if ((src == NULL) || ip6_addr_isany(src)) {
/* 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);
}
static INT __inetPing6FindSrc (struct netif *netif,
struct ip6_addr *pip6addrDest,
struct ip6_addr *pip6addrSrc)
{
static struct ip6_addr ip6addrAny = {{0, 0, 0, 0}};
struct ip6_addr *pip6addr;
if (netif == LW_NULL) {
netif = ip6_route(&ip6addrAny, pip6addrDest);
if (netif == LW_NULL) {
return (-1);
}
}
pip6addr = ip6_select_source_address(netif, pip6addrDest);
if (pip6addr == NULL) {
return (-2);
}
*pip6addrSrc = *pip6addr;
return (ERROR_NONE);
}
/**
* 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
* 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 == 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, ip6_addr_t *src, 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;
/* pbufs passed to IP must have a ref-count of 1 as their payload pointer
gets altered as the packet is passed down the stack */
LWIP_ASSERT("p->ref == 1", p->ref == 1);
/* Should the IPv6 header be generated or is it already included in p? */
if (dest != 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_ANY;
}
else if (ip6_addr_isany(src)) {
src = ip6_select_source_address(netif, dest);
if ((src == NULL) || ip6_addr_isany(src)) {
/* 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;
}
}
/* 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], netif->num));
ip6_debug_print(p);
#if ENABLE_LOOPBACK
/* TODO implement loopback for v6
if (ip6_addr_cmp(dest, netif_ip6_addr(0))) {
return netif_loop_output(netif, p, dest);
}*/
#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()"));
return netif->output_ip6(netif, p, dest);
}
/**
* 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);
}
