/*
* sends an IP packet, if it's alredy constructed
*/
static ssize_t
_sendip(struct iodesc * d, struct ip * ip, size_t len)
{
u_char *ea;
if (ip->ip_dst.s_addr == INADDR_BROADCAST || ip->ip_src.s_addr == 0 ||
netmask == 0 || SAMENET(ip->ip_src, ip->ip_dst, netmask)) {
ea = arpwhohas(d, ip->ip_dst);
} else {
ea = arpwhohas(d, gateip);
}
return sendether(d, ip, len, ea, ETHERTYPE_IP);
}
/* Caller must leave room for ethernet, ip and udp headers in front!! */
ssize_t
sendudp(struct iodesc *d, void *pkt, size_t len)
{
ssize_t cc;
struct ip *ip;
struct udpiphdr *ui;
struct udphdr *uh;
u_char *ea;
struct ip tip;
#ifdef NET_DEBUG
if (debug) {
printf("sendudp: d=%x called.\n", (u_int)d);
if (d) {
printf("saddr: %s:%d",
inet_ntoa(d->myip), ntohs(d->myport));
printf(" daddr: %s:%d\n",
inet_ntoa(d->destip), ntohs(d->destport));
}
}
#endif
uh = (struct udphdr *)pkt - 1;
ip = (struct ip *)uh - 1;
len += sizeof(*ip) + sizeof(*uh);
bzero(ip, sizeof(*ip) + sizeof(*uh));
ip->ip_v = IPVERSION; /* half-char */
ip->ip_hl = sizeof(*ip) >> 2; /* half-char */
ip->ip_len = htons(len);
ip->ip_p = IPPROTO_UDP; /* char */
ip->ip_ttl = IP_TTL; /* char */
ip->ip_src = d->myip;
ip->ip_dst = d->destip;
ip->ip_sum = in_cksum(ip, sizeof(*ip)); /* short, but special */
uh->uh_sport = d->myport;
uh->uh_dport = d->destport;
uh->uh_ulen = htons(len - sizeof(*ip));
/* Calculate checksum (must save and restore ip header) */
tip = *ip;
ui = (struct udpiphdr *)ip;
bzero(ui->ui_x1, sizeof(ui->ui_x1));
ui->ui_len = uh->uh_ulen;
uh->uh_sum = in_cksum(ui, len);
*ip = tip;
if (ip->ip_dst.s_addr == INADDR_BROADCAST || ip->ip_src.s_addr == 0 ||
netmask == 0 || SAMENET(ip->ip_src, ip->ip_dst, netmask))
ea = arpwhohas(d, ip->ip_dst);
else
ea = arpwhohas(d, gateip);
cc = sendether(d, ip, len, ea, ETHERTYPE_IP);
if (cc < 0)
return (-1);
if ((size_t)cc != len)
panic("sendudp: bad write (%d != %d)", cc, len);
return (cc - (sizeof(*ip) + sizeof(*uh)));
}
