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/*
* ip-cooked.c
*
* Copyright (c) 2001 Dug Song <dugsong@monkey.org>
*
* $Id: ip-cooked.c 547 2005-01-25 21:30:40Z dugsong $
*/
#ifdef _WIN32
#include "dnet_winconfig.h"
#else
#include "config.h"
#endif
#ifndef _WIN32
#include <netinet/in.h>
#include <unistd.h>
#endif
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "dnet.h"
#include "queue.h"
struct ip_intf {
eth_t *eth;
char name[INTF_NAME_LEN];
struct addr ha;
struct addr pa;
int mtu;
LIST_ENTRY(ip_intf) next;
};
struct ip_handle {
arp_t *arp;
intf_t *intf;
route_t *route;
int fd;
struct sockaddr_in sin;
LIST_HEAD(, ip_intf) ip_intf_list;
};
static int
_add_ip_intf(const struct intf_entry *entry, void *arg)
{
ip_t *ip = (ip_t *)arg;
struct ip_intf *ipi;
if (entry->intf_type == INTF_TYPE_ETH &&
(entry->intf_flags & INTF_FLAG_UP) != 0 &&
entry->intf_mtu >= ETH_LEN_MIN &&
entry->intf_addr.addr_type == ADDR_TYPE_IP &&
entry->intf_link_addr.addr_type == ADDR_TYPE_ETH) {
if ((ipi = calloc(1, sizeof(*ipi))) == NULL)
return (-1);
strlcpy(ipi->name, entry->intf_name, sizeof(ipi->name));
memcpy(&ipi->ha, &entry->intf_link_addr, sizeof(ipi->ha));
memcpy(&ipi->pa, &entry->intf_addr, sizeof(ipi->pa));
ipi->mtu = entry->intf_mtu;
LIST_INSERT_HEAD(&ip->ip_intf_list, ipi, next);
}
return (0);
}
ip_t *
ip_open(void)
{
ip_t *ip;
if ((ip = calloc(1, sizeof(*ip))) != NULL) {
ip->fd = -1;
if ((ip->arp = arp_open()) == NULL ||
(ip->intf = intf_open()) == NULL ||
(ip->route = route_open()) == NULL)
return (ip_close(ip));
if ((ip->fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
return (ip_close(ip));
memset(&ip->sin, 0, sizeof(ip->sin));
ip->sin.sin_family = AF_INET;
ip->sin.sin_port = htons(666);
LIST_INIT(&ip->ip_intf_list);
if (intf_loop(ip->intf, _add_ip_intf, ip) != 0)
return (ip_close(ip));
}
return (ip);
}
static struct ip_intf *
_lookup_ip_intf(ip_t *ip, ip_addr_t dst)
{
struct ip_intf *ipi;
int n;
ip->sin.sin_addr.s_addr = dst;
n = sizeof(ip->sin);
if (connect(ip->fd, (struct sockaddr *)&ip->sin, n) < 0)
return (NULL);
if (getsockname(ip->fd, (struct sockaddr *)&ip->sin, &n) < 0)
return (NULL);
LIST_FOREACH(ipi, &ip->ip_intf_list, next) {
if (ipi->pa.addr_ip == ip->sin.sin_addr.s_addr) {
if (ipi->eth == NULL) {
if ((ipi->eth = eth_open(ipi->name)) == NULL)
return (NULL);
}
if (ipi != LIST_FIRST(&ip->ip_intf_list)) {
LIST_REMOVE(ipi, next);
LIST_INSERT_HEAD(&ip->ip_intf_list, ipi, next);
}
return (ipi);
}
}
return (NULL);
}
static void
_request_arp(struct ip_intf *ipi, struct addr *dst)
{
u_char frame[ETH_HDR_LEN + ARP_HDR_LEN + ARP_ETHIP_LEN];
eth_pack_hdr(frame, ETH_ADDR_BROADCAST, ipi->ha.addr_eth,
ETH_TYPE_ARP);
arp_pack_hdr_ethip(frame + ETH_HDR_LEN, ARP_OP_REQUEST,
ipi->ha.addr_eth, ipi->pa.addr_ip, ETH_ADDR_BROADCAST,
dst->addr_ip);
eth_send(ipi->eth, frame, sizeof(frame));
}
ssize_t
ip_send(ip_t *ip, const void *buf, size_t len)
{
struct ip_hdr *iph;
struct ip_intf *ipi;
struct arp_entry arpent;
struct route_entry rtent;
u_char frame[ETH_LEN_MAX];
int i, usec;
iph = (struct ip_hdr *)buf;
if ((ipi = _lookup_ip_intf(ip, iph->ip_dst)) == NULL) {
errno = EHOSTUNREACH;
return (-1);
}
arpent.arp_pa.addr_type = ADDR_TYPE_IP;
arpent.arp_pa.addr_bits = IP_ADDR_BITS;
arpent.arp_pa.addr_ip = iph->ip_dst;
memcpy(&rtent.route_dst, &arpent.arp_pa, sizeof(rtent.route_dst));
for (i = 0, usec = 10; i < 3; i++, usec *= 100) {
if (arp_get(ip->arp, &arpent) == 0)
break;
if (route_get(ip->route, &rtent) == 0 &&
rtent.route_gw.addr_ip != ipi->pa.addr_ip) {
memcpy(&arpent.arp_pa, &rtent.route_gw,
sizeof(arpent.arp_pa));
if (arp_get(ip->arp, &arpent) == 0)
break;
}
_request_arp(ipi, &arpent.arp_pa);
usleep(usec);
}
if (i == 3)
memset(&arpent.arp_ha.addr_eth, 0xff, ETH_ADDR_LEN);
eth_pack_hdr(frame, arpent.arp_ha.addr_eth,
ipi->ha.addr_eth, ETH_TYPE_IP);
if (len > ipi->mtu) {
u_char *p, *start, *end, *ip_data;
int ip_hl, fraglen;
ip_hl = iph->ip_hl << 2;
fraglen = ipi->mtu - ip_hl;
iph = (struct ip_hdr *)(frame + ETH_HDR_LEN);
memcpy(iph, buf, ip_hl);
ip_data = (u_char *)iph + ip_hl;
start = (u_char *)buf + ip_hl;
end = (u_char *)buf + len;
for (p = start; p < end; ) {
memcpy(ip_data, p, fraglen);
iph->ip_len = htons(ip_hl + fraglen);
iph->ip_off = htons(((p + fraglen < end) ? IP_MF : 0) |
((p - start) >> 3));
ip_checksum(iph, ip_hl + fraglen);
i = ETH_HDR_LEN + ip_hl + fraglen;
if (eth_send(ipi->eth, frame, i) != i)
return (-1);
p += fraglen;
if (end - p < fraglen)
fraglen = end - p;
}
return (len);
}
memcpy(frame + ETH_HDR_LEN, buf, len);
i = ETH_HDR_LEN + len;
if (eth_send(ipi->eth, frame, i) != i)
return (-1);
return (len);
}
ip_t *
ip_close(ip_t *ip)
{
struct ip_intf *ipi, *nxt;
if (ip != NULL) {
for (ipi = LIST_FIRST(&ip->ip_intf_list);
ipi != LIST_END(&ip->ip_intf_list); ipi = nxt) {
nxt = LIST_NEXT(ipi, next);
if (ipi->eth != NULL)
eth_close(ipi->eth);
free(ipi);
}
if (ip->fd >= 0)
close(ip->fd);
if (ip->route != NULL)
route_close(ip->route);
if (ip->intf != NULL)
intf_close(ip->intf);
if (ip->arp != NULL)
arp_close(ip->arp);
free(ip);
}
return (NULL);
}
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