/*
* OpenVPN -- An application to securely tunnel IP networks
* over a single TCP/UDP port, with support for SSL/TLS-based
* session authentication and key exchange,
* packet encryption, packet authentication, and
* packet compression.
*
* Copyright (C) 2002-2009 OpenVPN Technologies, Inc. <sales@openvpn.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program (see the file COPYING included with this
* distribution); if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "syshead.h"
#if P2MP_SERVER
#include "mroute.h"
#include "proto.h"
#include "error.h"
#include "socket.h"
#include "memdbg.h"
void
mroute_addr_init (struct mroute_addr *addr)
{
CLEAR (*addr);
}
/*
* Ethernet multicast addresses.
*/
static inline bool
is_mac_mcast_addr (const uint8_t *mac)
{
return (bool) mac[0] & 1;
}
static inline bool
is_mac_mcast_maddr (const struct mroute_addr *addr)
{
return (addr->type & MR_ADDR_MASK) == MR_ADDR_ETHER && is_mac_mcast_addr (addr->addr);
}
/*
* Don't learn certain addresses.
*/
bool
mroute_learnable_address (const struct mroute_addr *addr)
{
int i;
bool not_all_zeros = false;
bool not_all_ones = false;
for (i = 0; i < addr->len; ++i)
{
int b = addr->addr[i];
if (b != 0x00)
not_all_zeros = true;
if (b != 0xFF)
not_all_ones = true;
}
return not_all_zeros && not_all_ones && !is_mac_mcast_maddr (addr);
}
static inline void
mroute_get_in_addr_t (struct mroute_addr *ma, const in_addr_t src, unsigned int mask)
{
if (ma)
{
ma->type = MR_ADDR_IPV4 | mask;
ma->netbits = 0;
ma->len = 4;
*(in_addr_t*)ma->addr = src;
}
}
static inline bool
mroute_is_mcast (const in_addr_t addr)
{
return ((addr & htonl(IP_MCAST_SUBNET_MASK)) == htonl(IP_MCAST_NETWORK));
}
#ifdef ENABLE_PF
static unsigned int
mroute_extract_addr_arp (struct mroute_addr *src,
struct mroute_addr *dest,
const struct buffer *buf)
{
unsigned int ret = 0;
if (BLEN (buf) >= (int) sizeof (struct openvpn_arp))
{
const struct openvpn_arp *arp = (const struct openvpn_arp *) BPTR (buf);
if (arp->mac_addr_type == htons(0x0001)
&& arp->proto_addr_type == htons(0x0800)
&& arp->mac_addr_size == 0x06
&& arp->proto_addr_size == 0x04)
{
mroute_get_in_addr_t (src, arp->ip_src, MR_ARP);
mroute_get_in_addr_t (dest, arp->ip_dest, MR_ARP);
/* multicast packet? */
if (mroute_is_mcast (arp->ip_dest))
ret |= MROUTE_EXTRACT_MCAST;
ret |= MROUTE_EXTRACT_SUCCEEDED;
}
}
return ret;
}
#endif
unsigned int
mroute_extract_addr_ipv4 (struct mroute_addr *src,
struct mroute_addr *dest,
const struct buffer *buf)
{
unsigned int ret = 0;
if (BLEN (buf) >= 1)
{
switch (OPENVPN_IPH_GET_VER (*BPTR(buf)))
{
case 4:
if (BLEN (buf) >= (int) sizeof (struct openvpn_iphdr))
{
const struct openvpn_iphdr *ip = (const struct openvpn_iphdr *) BPTR (buf);
mroute_get_in_addr_t (src, ip->saddr, 0);
mroute_get_in_addr_t (dest, ip->daddr, 0);
/* multicast packet? */
if (mroute_is_mcast (ip->daddr))
ret |= MROUTE_EXTRACT_MCAST;
/* IGMP message? */
if (ip->protocol == OPENVPN_IPPROTO_IGMP)
ret |= MROUTE_EXTRACT_IGMP;
ret |= MROUTE_EXTRACT_SUCCEEDED;
}
break;
case 6:
{
msg (M_WARN, "Need IPv6 code in mroute_extract_addr_from_packet");
break;
}
}
}
return ret;
}
unsigned int
mroute_extract_addr_ether (struct mroute_addr *src,
struct mroute_addr *dest,
struct mroute_addr *esrc,
struct mroute_addr *edest,
const struct buffer *buf)
{
unsigned int ret = 0;
if (BLEN (buf) >= (int) sizeof (struct openvpn_ethhdr))
{
const struct openvpn_ethhdr *eth = (const struct openvpn_ethhdr *) BPTR (buf);
if (src)
{
src->type = MR_ADDR_ETHER;
src->netbits = 0;
src->len = 6;
memcpy (src->addr, eth->source, 6);
}
if (dest)
{
dest->type = MR_ADDR_ETHER;
dest->netbits = 0;
dest->len = 6;
memcpy (dest->addr, eth->dest, 6);
/* ethernet broadcast/multicast packet? */
if (is_mac_mcast_addr (eth->dest))
ret |= MROUTE_EXTRACT_BCAST;
}
ret |= MROUTE_EXTRACT_SUCCEEDED;
#ifdef ENABLE_PF
if (esrc || edest)
{
struct buffer b = *buf;
if (buf_advance (&b, sizeof (struct openvpn_ethhdr)))
{
switch (ntohs (eth->proto))
{
case OPENVPN_ETH_P_IPV4:
ret |= (mroute_extract_addr_ipv4 (esrc, edest, &b) << MROUTE_SEC_SHIFT);
break;
case OPENVPN_ETH_P_ARP:
ret |= (mroute_extract_addr_arp (esrc, edest, &b) << MROUTE_SEC_SHIFT);
break;
}
}
}
#endif
}
return ret;
}
/*
* Translate a struct openvpn_sockaddr (osaddr)
* to a struct mroute_addr (addr).
*/
bool mroute_extract_openvpn_sockaddr (struct mroute_addr *addr,
const struct openvpn_sockaddr *osaddr,
bool use_port)
{
if (osaddr->sa.sin_family == AF_INET)
{
if (use_port)
{
addr->type = MR_ADDR_IPV4 | MR_WITH_PORT;
addr->netbits = 0;
addr->len = 6;
memcpy (addr->addr, &osaddr->sa.sin_addr.s_addr, 4);
memcpy (addr->addr + 4, &osaddr->sa.sin_port, 2);
}
else
{
addr->type = MR_ADDR_IPV4;
addr->netbits = 0;
addr->len = 4;
memcpy (addr->addr, &osaddr->sa.sin_addr.s_addr, 4);
}
return true;
}
return false;
}
/*
* Zero off the host bits in an address, leaving
* only the network bits, using the netbits member of
* struct mroute_addr as the controlling parameter.
*/
void
mroute_addr_mask_host_bits (struct mroute_addr *ma)
{
in_addr_t addr = ntohl(*(in_addr_t*)ma->addr);
ASSERT ((ma->type & MR_ADDR_MASK) == MR_ADDR_IPV4);
addr &= netbits_to_netmask (ma->netbits);
*(in_addr_t*)ma->addr = htonl (addr);
}
/*
* The mroute_addr hash function takes into account the
* address type, number of bits in the network address,
* and the actual address.
*/
uint32_t
mroute_addr_hash_function (const void *key, uint32_t iv)
{
return hash_func (mroute_addr_hash_ptr ((const struct mroute_addr *) key),
mroute_addr_hash_len ((const struct mroute_addr *) key),
iv);
}
bool
mroute_addr_compare_function (const void *key1, const void *key2)
{
return mroute_addr_equal ((const struct mroute_addr *) key1,
(const struct mroute_addr *) key2);
}
const char *
mroute_addr_print (const struct mroute_addr *ma,
struct gc_arena *gc)
{
return mroute_addr_print_ex (ma, MAPF_IA_EMPTY_IF_UNDEF, gc);
}
const char *
mroute_addr_print_ex (const struct mroute_addr *ma,
const unsigned int flags,
struct gc_arena *gc)
{
struct buffer out = alloc_buf_gc (64, gc);
if (ma)
{
struct mroute_addr maddr = *ma;
switch (maddr.type & MR_ADDR_MASK)
{
case MR_ADDR_ETHER:
buf_printf (&out, "%s", format_hex_ex (ma->addr, 6, 0, 1, ":", gc));
break;
case MR_ADDR_IPV4:
{
struct buffer buf;
in_addr_t addr;
int port;
bool status;
buf_set_read (&buf, maddr.addr, maddr.len);
addr = buf_read_u32 (&buf, &status);
if (status)
{
if ((flags & MAPF_SHOW_ARP) && (maddr.type & MR_ARP))
buf_printf (&out, "ARP/");
buf_printf (&out, "%s", print_in_addr_t (addr, (flags & MAPF_IA_EMPTY_IF_UNDEF) ? IA_EMPTY_IF_UNDEF : 0, gc));
if (maddr.type & MR_WITH_NETBITS)
{
if (flags & MAPF_SUBNET)
{
const in_addr_t netmask = netbits_to_netmask (maddr.netbits);
buf_printf (&out, "/%s", print_in_addr_t (netmask, 0, gc));
}
else
buf_printf (&out, "/%d", maddr.netbits);
}
}
if (maddr.type & MR_WITH_PORT)
{
port = buf_read_u16 (&buf);
if (port >= 0)
buf_printf (&out, ":%d", port);
}
}
break;
case MR_ADDR_IPV6:
buf_printf (&out, "IPV6");
break;
default:
buf_printf (&out, "UNKNOWN");
break;
}
return BSTR (&out);
}
else
return "[NULL]";
}
/*
* mroute_helper's main job is keeping track of
* currently used CIDR netlengths, so we don't
* have to cycle through all 33.
*/
struct mroute_helper *
mroute_helper_init (int ageable_ttl_secs)
{
struct mroute_helper *mh;
ALLOC_OBJ_CLEAR (mh, struct mroute_helper);
/*mutex_init (&mh->mutex);*/
mh->ageable_ttl_secs = ageable_ttl_secs;
return mh;
}
static void
mroute_helper_regenerate (struct mroute_helper *mh)
{
int i, j = 0;
for (i = MR_HELPER_NET_LEN - 1; i >= 0; --i)
{
if (mh->net_len_refcount[i] > 0)
mh->net_len[j++] = (uint8_t) i;
}
mh->n_net_len = j;
#ifdef ENABLE_DEBUG
if (check_debug_level (D_MULTI_DEBUG))
{
struct gc_arena gc = gc_new ();
struct buffer out = alloc_buf_gc (256, &gc);
buf_printf (&out, "MROUTE CIDR netlen:");
for (i = 0; i < mh->n_net_len; ++i)
{
buf_printf (&out, " /%d", mh->net_len[i]);
}
dmsg (D_MULTI_DEBUG, "%s", BSTR (&out));
gc_free (&gc);
}
#endif
}
void
mroute_helper_add_iroute (struct mroute_helper *mh, const struct iroute *ir)
{
if (ir->netbits >= 0)
{
ASSERT (ir->netbits < MR_HELPER_NET_LEN);
mroute_helper_lock (mh);
++mh->cache_generation;
++mh->net_len_refcount[ir->netbits];
if (mh->net_len_refcount[ir->netbits] == 1)
mroute_helper_regenerate (mh);
mroute_helper_unlock (mh);
}
}
void
mroute_helper_del_iroute (struct mroute_helper *mh, const struct iroute *ir)
{
if (ir->netbits >= 0)
{
ASSERT (ir->netbits < MR_HELPER_NET_LEN);
mroute_helper_lock (mh);
++mh->cache_generation;
--mh->net_len_refcount[ir->netbits];
ASSERT (mh->net_len_refcount[ir->netbits] >= 0);
if (!mh->net_len_refcount[ir->netbits])
mroute_helper_regenerate (mh);
mroute_helper_unlock (mh);
}
}
void
mroute_helper_free (struct mroute_helper *mh)
{
/*mutex_destroy (&mh->mutex);*/
free (mh);
}
#else
static void dummy(void) {}
#endif /* P2MP_SERVER */