/*
* fills out the IP header
* Caller must leave room for ethernet, ip and udp headers in front!
*/
ssize_t
sendip(struct iodesc * d, void *pkt, size_t len, u_int8_t proto)
{
ssize_t cc;
struct ip *ip;
ip = (struct ip *) pkt - 1;
len += sizeof(*ip);
(void) memset(ip, 0, sizeof(*ip));
ip->ip_v = IPVERSION;
ip->ip_hl = sizeof(*ip) >> 2;
ip->ip_len = htons(len);
ip->ip_p = proto;
ip->ip_ttl = IPDEFTTL;
ip->ip_src = d->myip;
ip->ip_dst = d->destip;
ip->ip_sum = ip_cksum(ip, sizeof(*ip));
cc = _sendip(d, ip, len);
if (cc == -1)
return -1;
if ((size_t) cc != len)
panic("sendip: bad write (%zd != %zu)", cc, len);
return (cc - (sizeof(*ip)));
}
/*ARGSUSED*/
static int
ip_isvalidchecksum(net_handle_t neti, mblk_t *mp)
{
unsigned char *wptr;
ipha_t *ipha = (ipha_t *)mp->b_rptr;
int hlen;
int ret;
ASSERT(mp != NULL);
if (dohwcksum &&
DB_CKSUM16(mp) != 0xFFFF &&
(DB_CKSUMFLAGS(mp) & HCK_FULLCKSUM) &&
(DB_CKSUMFLAGS(mp) & HCK_FULLCKSUM_OK) &&
(DB_CKSUMFLAGS(mp) & HCK_IPV4_HDRCKSUM))
return (1);
hlen = (ipha->ipha_version_and_hdr_length & 0x0F) << 2;
/*
* Check that the mblk being passed in has enough data in it
* before blindly checking ip_cksum.
*/
if (msgdsize(mp) < hlen)
return (0);
if (mp->b_wptr < mp->b_rptr + hlen) {
if (pullupmsg(mp, hlen) == 0)
return (0);
wptr = mp->b_wptr;
} else {
wptr = mp->b_wptr;
mp->b_wptr = mp->b_rptr + hlen;
}
if (ipha->ipha_hdr_checksum == ip_cksum(mp, 0, ipha->ipha_hdr_checksum))
ret = 1;
else
ret = 0;
mp->b_wptr = wptr;
return (ret);
}
/*
* reads an IP packet
* WARNING: the old version stripped the IP options, if there were
* any. Because we have absolutely no idea if the upper layer needs
* these or not, it's best to leave them there.
*
* The size returned is the size indicated in the header.
*/
ssize_t
readip(struct iodesc * d, void *pkt, size_t len, time_t tleft, u_int8_t proto)
{
ssize_t n;
size_t hlen;
struct ip *ip;
u_int16_t etype;
ip = (struct ip *) pkt - 1;
n = readether(d, ip, len + sizeof(*ip), tleft, &etype);
if (n == -1 || (size_t) n < sizeof(*ip))
return -1;
if (etype == ETHERTYPE_ARP) {
struct arphdr *ah = (void *) ip;
if (ah->ar_op == htons(ARPOP_REQUEST)) {
/* Send ARP reply */
arp_reply(d, ah);
}
return -1;
}
if (etype != ETHERTYPE_IP) {
#ifdef NET_DEBUG
if (debug)
printf("readip: not IP. ether_type=%x\n", etype);
#endif
return -1;
}
/* Check ip header */
if (ip->ip_v != IPVERSION ||
ip->ip_p != proto) { /* half char */
#ifdef NET_DEBUG
if (debug) {
printf("readip: wrong IP version or wrong proto "
"ip_v=%d ip_p=%d\n", ip->ip_v, ip->ip_p);
}
#endif
return -1;
}
hlen = ip->ip_hl << 2;
if (hlen < sizeof(*ip) || ip_cksum(ip, hlen) != 0) {
#ifdef NET_DEBUG
if (debug)
printf("readip: short hdr or bad cksum.\n");
#endif
return -1;
}
if (n < ntohs(ip->ip_len)) {
#ifdef NET_DEBUG
if (debug)
printf("readip: bad length %d < %d.\n",
(int) n, ntohs(ip->ip_len));
#endif
return -1;
}
if (d->myip.s_addr && ip->ip_dst.s_addr != d->myip.s_addr) {
#ifdef NET_DEBUG
if (debug) {
printf("readip: bad saddr %s != ", inet_ntoa(d->myip));
printf("%s\n", inet_ntoa(ip->ip_dst));
}
#endif
return -1;
}
return (ntohs(ip->ip_len) - 20);
}
/* 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 udphdr *uh;
u_char *ea;
#ifdef NET_DEBUG
if (debug) {
printf("sendudp: d=%lx called.\n", (long)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);
(void)memset(ip, 0, 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 = IPDEFTTL; /* char */
ip->ip_src = d->myip;
ip->ip_dst = d->destip;
ip->ip_sum = ip_cksum(ip, sizeof(*ip)); /* short, but special */
uh->uh_sport = d->myport;
uh->uh_dport = d->destport;
uh->uh_ulen = htons(len - sizeof(*ip));
#ifndef UDP_NO_CKSUM
{
struct udpiphdr *ui;
struct ip tip;
/* Calculate checksum (must save and restore ip header) */
tip = *ip;
ui = (struct udpiphdr *)ip;
(void)memset(ui->ui_x1, 0, sizeof(ui->ui_x1));
ui->ui_len = uh->uh_ulen;
uh->uh_sum = ip_cksum(ui, len);
*ip = tip;
}
#endif
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 == -1)
return -1;
if ((size_t)cc != len)
panic("sendudp: bad write (%d != %d)", cc, len);
return (cc - (sizeof(*ip) + sizeof(*uh)));
}
/*
* Receive a UDP packet and validate it is for us.
* Caller leaves room for the headers (Ether, IP, UDP)
*/
ssize_t
readudp(struct iodesc *d, void *pkt, size_t len, time_t tleft)
{
ssize_t n;
size_t hlen;
struct ip *ip;
struct udphdr *uh;
u_int16_t etype; /* host order */
#ifdef NET_DEBUG
if (debug)
printf("readudp: called\n");
#endif
uh = (struct udphdr *)pkt - 1;
ip = (struct ip *)uh - 1;
n = readether(d, ip, len + sizeof(*ip) + sizeof(*uh), tleft, &etype);
if (n == -1 || (size_t)n < sizeof(*ip) + sizeof(*uh))
return -1;
/* Ethernet address checks now in readether() */
/* Need to respond to ARP requests. */
if (etype == ETHERTYPE_ARP) {
struct arphdr *ah = (void *)ip;
if (ah->ar_op == htons(ARPOP_REQUEST)) {
/* Send ARP reply */
arp_reply(d, ah);
}
return -1;
}
if (etype != ETHERTYPE_IP) {
#ifdef NET_DEBUG
if (debug)
printf("readudp: not IP. ether_type=%x\n", etype);
#endif
return -1;
}
/* Check ip header */
if (ip->ip_v != IPVERSION ||
ip->ip_p != IPPROTO_UDP) { /* half char */
#ifdef NET_DEBUG
if (debug) {
printf("readudp: IP version or not UDP. "
"ip_v=%d ip_p=%d\n", ip->ip_v, ip->ip_p);
}
#endif
return -1;
}
hlen = ip->ip_hl << 2;
if (hlen < sizeof(*ip) || ip_cksum(ip, hlen) != 0) {
#ifdef NET_DEBUG
if (debug)
printf("readudp: short hdr or bad cksum.\n");
#endif
return -1;
}
if (n < ntohs(ip->ip_len)) {
#ifdef NET_DEBUG
if (debug)
printf("readudp: bad length %d < %d.\n",
(int)n, ntohs(ip->ip_len));
#endif
return -1;
}
if (d->myip.s_addr && ip->ip_dst.s_addr != d->myip.s_addr) {
#ifdef NET_DEBUG
if (debug) {
printf("readudp: bad saddr %s != ", inet_ntoa(d->myip));
printf("%s\n", inet_ntoa(ip->ip_dst));
}
#endif
return -1;
}
/* If there were ip options, make them go away */
if (hlen != sizeof(*ip)) {
(void)memcpy(uh, ((u_char *)ip) + hlen, len - hlen);
ip->ip_len = htons(sizeof(*ip));
n -= hlen - sizeof(*ip);
}
if (uh->uh_dport != d->myport) {
#ifdef NET_DEBUG
if (debug)
printf("readudp: bad dport %d != %d\n",
d->myport, ntohs(uh->uh_dport));
#endif
return -1;
}
#ifndef UDP_NO_CKSUM
if (uh->uh_sum) {
struct udpiphdr *ui;
struct ip tip;
n = ntohs(uh->uh_ulen) + sizeof(*ip);
if (n > RECV_SIZE - ETHER_SIZE) {
printf("readudp: huge packet, udp len %d\n", (int)n);
return -1;
}
/* Check checksum (must save and restore ip header) */
tip = *ip;
ui = (struct udpiphdr *)ip;
(void)memset(ui->ui_x1, 0, sizeof(ui->ui_x1));
ui->ui_len = uh->uh_ulen;
if (ip_cksum(ui, n) != 0) {
#ifdef NET_DEBUG
if (debug)
printf("readudp: bad cksum\n");
#endif
*ip = tip;
return -1;
}
*ip = tip;
}
#endif
if (ntohs(uh->uh_ulen) < sizeof(*uh)) {
#ifdef NET_DEBUG
if (debug)
printf("readudp: bad udp len %d < %d\n",
ntohs(uh->uh_ulen), (int)sizeof(*uh));
#endif
return -1;
}
n -= sizeof(*ip) + sizeof(*uh);
return n;
}
