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import of dnsmasq-2.5.tar.gz

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This commit is contained in:
Simon Kelley
2004-03-16 18:35:52 +00:00
parent 1cff166d37
commit 8a911ccc75
12 changed files with 116 additions and 58 deletions
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57
src/dhcp.c
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@@ -75,7 +75,8 @@ void dhcp_packet(struct dhcp_context *contexts, char *packet,
struct iovec iov[2];
struct cmsghdr *cmptr;
int sz, newlen, iface_index = 0;
struct in_addr source, real_netmask, iface_addr, netmask_save, broadcast_save;
struct in_addr source, iface_netmask, iface_addr, iface_broadcast;
struct in_addr netmask_save, broadcast_save, router;
#ifdef HAVE_BPF
unsigned char iface_hwaddr[ETHER_ADDR_LEN];
#endif
@@ -112,7 +113,8 @@ void dhcp_packet(struct dhcp_context *contexts, char *packet,
if (cmptr->cmsg_level == SOL_IP && cmptr->cmsg_type == IP_PKTINFO)
iface_index = ((struct in_pktinfo *)CMSG_DATA(cmptr))->ipi_ifindex;
if (!iface_index || !if_indextoname(iface_index, ifr.ifr_name))
if (!(ifr.ifr_ifindex = iface_index) ||
ioctl(dhcp_fd, SIOCGIFNAME, &ifr) == -1)
return;
#elif defined(IP_RECVIF)
@@ -169,17 +171,30 @@ void dhcp_packet(struct dhcp_context *contexts, char *packet,
/* If the packet came via a relay, use that address to look up the context,
else use the address of the interface is arrived on. */
source = mess->giaddr.s_addr ? mess->giaddr : iface_addr;
iface_netmask.s_addr = 0;
iface_broadcast.s_addr = 0;
if (ioctl(dhcp_fd, SIOCGIFNETMASK, &ifr) != -1)
{
iface_netmask = ((struct sockaddr_in *) &ifr.ifr_addr)->sin_addr;
/* we can use the interface netmask if either the packet came direct,
or it came via a relay listening on the same network. This sounds unlikely,
but it happens with win4lin. */
if ((source.s_addr & iface_netmask.s_addr) != (iface_addr.s_addr & iface_netmask.s_addr))
iface_netmask.s_addr = 0;
else if (ioctl(dhcp_fd, SIOCGIFBRDADDR, &ifr) != -1)
iface_broadcast = ((struct sockaddr_in *) &ifr.ifr_addr)->sin_addr;
}
for (context = contexts; context; context = context->next)
{
if (!context->netmask.s_addr && !mess->giaddr.s_addr && ioctl(dhcp_fd, SIOCGIFNETMASK, &ifr) != -1)
real_netmask = ((struct sockaddr_in *) &ifr.ifr_addr)->sin_addr;
else
real_netmask = context->netmask;
if (real_netmask.s_addr &&
(source.s_addr & real_netmask.s_addr) == (context->start.s_addr & real_netmask.s_addr) &&
(source.s_addr & real_netmask.s_addr) == (context->end.s_addr & real_netmask.s_addr))
struct in_addr netmask = context->netmask.s_addr ? context->netmask : iface_netmask;
if (netmask.s_addr &&
(source.s_addr & netmask.s_addr) == (context->start.s_addr & netmask.s_addr) &&
(source.s_addr & netmask.s_addr) == (context->end.s_addr & netmask.s_addr))
break;
}
@@ -192,26 +207,34 @@ void dhcp_packet(struct dhcp_context *contexts, char *packet,
netmask_save = context->netmask;
broadcast_save = context->broadcast;
context->netmask = real_netmask;
if (!context->netmask.s_addr)
context->netmask = iface_netmask;
if (!context->broadcast.s_addr)
{
if (mess->giaddr.s_addr)
context->broadcast.s_addr = (mess->giaddr.s_addr & real_netmask.s_addr) | ~real_netmask.s_addr;
else if (ioctl(dhcp_fd, SIOCGIFBRDADDR, &ifr) != -1)
context->broadcast = ((struct sockaddr_in *) &ifr.ifr_addr)->sin_addr;
if (iface_broadcast.s_addr)
context->broadcast = iface_broadcast;
else
context->broadcast.s_addr = (iface_addr.s_addr & real_netmask.s_addr) | ~real_netmask.s_addr;
context->broadcast.s_addr = (source.s_addr & context->netmask.s_addr) | ~context->netmask.s_addr;
}
if (ioctl(dhcp_fd, SIOCGIFMTU, &ifr) == -1)
ifr.ifr_mtu = ETHERMTU;
/* Normally, we set the default route to point to the machine which is getting the
DHCP broadcast, either this machine or a relay. In the special case that the relay
is on the same network as us, we set the default route to us, not the relay.
This is the win4lin scenario again. */
if ((source.s_addr & context->netmask.s_addr) == (iface_addr.s_addr & context->netmask.s_addr))
router = iface_addr;
else
router = source;
lease_prune(NULL, now); /* lose any expired leases */
newlen = dhcp_reply(context, iface_addr, ifr.ifr_name, ifr.ifr_mtu,
rawpacket, sz, now, namebuff,
dhcp_opts, dhcp_configs, domain_suffix, dhcp_file,
dhcp_sname, dhcp_next_server);
dhcp_sname, dhcp_next_server, router);
lease_update_file(0, now);
lease_update_dns();