int ndp_send(uint8_t type, uint8_t code, const void *body,
size_t body_sz, struct net_device *dev) {
struct sk_buff *skb;
struct in_device *in_dev;
struct in6_addr dst_ip6;
assert(dev != NULL);
skb = skb_alloc(dev->hdr_len + IP6_HEADER_SIZE
+ ICMP6_MIN_HEADER_SIZE + body_sz);
if (skb == NULL) {
return -ENOMEM;
}
skb->dev = dev;
skb->nh.raw = skb->mac.raw + dev->hdr_len;
skb->h.raw = skb->nh.raw + IP6_HEADER_SIZE;
in_dev = inetdev_get_by_dev(dev);
assert(in_dev != NULL);
inet_pton(AF_INET6, "ff02::1:ff02:10", &dst_ip6);
ip6_build(skb->nh.ip6h, ICMP6_MIN_HEADER_SIZE + body_sz,
IPPROTO_ICMPV6, 255, &in_dev->ifa6_address, &dst_ip6);
icmp6_build(skb->h.icmp6h, type, code, body, body_sz);
icmp6_set_check_field(skb->h.icmp6h, skb->nh.ip6h);
return ndp_xmit(skb, dev);
}
static inline ip6_addr
get_ip6_ll(const void *p)
{
return ip6_build(0xfe800000, 0, get_u32(p+0), get_u32(p+4));
}
static int ip6_make(const struct sock *sk,
const struct sockaddr *to,
size_t *data_size, struct sk_buff **out_skb) {
size_t hdr_size, max_size;
struct sk_buff *skb;
struct net_device *dev;
const struct inet6_sock *in6_sk;
const struct sockaddr_in6 *to_in6;
uint8_t nexthdr;
const struct in6_addr *src_ip6;
struct in6_addr dst_ip6;
assert((to == NULL) || (to->sa_family == AF_INET6));
assert(data_size != NULL);
assert(out_skb != NULL);
assert((sk != NULL) || (*out_skb != NULL));
in6_sk = to_const_inet6_sock(sk);
to_in6 = (const struct sockaddr_in6 *)to;
assert((to_in6 == NULL)
|| (to_in6->sin6_family == AF_INET6));
memcpy(&dst_ip6, to_in6 != NULL ? &to_in6->sin6_addr
: in6_sk != NULL ? &in6_sk->dst_in6.sin6_addr
: &(*out_skb)->nh.ip6h->saddr, /* make a reply */
sizeof dst_ip6);
/* FIXME use route */
if (0 == memcmp(&dst_ip6, &in6addr_loopback,
sizeof dst_ip6)) {
dev = netdev_get_by_name("lo");
}
else {
dev = netdev_get_by_name("eth0");
}
assert(dev != NULL);
assert(inetdev_get_by_dev(dev) != NULL);
src_ip6 = &inetdev_get_by_dev(dev)->ifa6_address;
nexthdr = in6_sk != NULL ? in6_sk->sk.opt.so_protocol
: (*out_skb)->nh.ip6h->nexthdr;
hdr_size = dev->hdr_len + IP6_HEADER_SIZE;
max_size = min(dev->mtu, skb_max_size());
if (hdr_size > max_size) {
return -EMSGSIZE;
}
*data_size = min(*data_size, max_size - hdr_size);
skb = skb_realloc(hdr_size + *data_size, *out_skb);
if (skb == NULL) {
return -ENOMEM;
}
skb->dev = dev;
skb->nh.raw = skb->mac.raw + dev->hdr_len;
skb->h.raw = skb->nh.raw + IP6_HEADER_SIZE;
ip6_build(skb->nh.ip6h, *data_size, nexthdr, 64, src_ip6,
&dst_ip6);
*out_skb = skb;
return 0;
}
