forecast: Add the broadcast/multicast forwarding plugin called forecast

This commit is contained in:
Martin Willi 2014-12-05 15:50:24 +01:00
parent c72fa57a00
commit e5ad2e6614
9 changed files with 1483 additions and 0 deletions

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@ -247,6 +247,7 @@ ARG_ENABL_SET([tnccs-dynamic], [enable dynamic TNCCS protocol discovery module.
ARG_ENABL_SET([android-log], [enable Android specific logger plugin.])
ARG_ENABL_SET([certexpire], [enable CSV export of expiration dates of used certificates.])
ARG_ENABL_SET([connmark], [enable connmark plugin using conntrack based marks to select return path SA.])
ARG_ENABL_SET([forecast], [enable forecast plugin forwarding broadcast/multicast messages.])
ARG_ENABL_SET([duplicheck], [advanced duplicate checking plugin using liveness checks.])
ARG_ENABL_SET([error-notify], [enable error notification plugin.])
ARG_ENABL_SET([farp], [enable ARP faking plugin that responds to ARP requests to peers virtual IP])
@ -1270,6 +1271,7 @@ ADD_PLUGIN([socket-default], [c charon nm cmd])
ADD_PLUGIN([socket-dynamic], [c charon cmd])
ADD_PLUGIN([socket-win], [c charon])
ADD_PLUGIN([connmark], [c charon])
ADD_PLUGIN([forecast], [c charon])
ADD_PLUGIN([farp], [c charon])
ADD_PLUGIN([stroke], [c charon])
ADD_PLUGIN([vici], [c charon])
@ -1478,6 +1480,7 @@ AM_CONDITIONAL(USE_SOCKET_DEFAULT, test x$socket_default = xtrue)
AM_CONDITIONAL(USE_SOCKET_DYNAMIC, test x$socket_dynamic = xtrue)
AM_CONDITIONAL(USE_SOCKET_WIN, test x$socket_win = xtrue)
AM_CONDITIONAL(USE_CONNMARK, test x$connmark = xtrue)
AM_CONDITIONAL(USE_FORECAST, test x$forecast = xtrue)
AM_CONDITIONAL(USE_FARP, test x$farp = xtrue)
AM_CONDITIONAL(USE_ADDRBLOCK, test x$addrblock = xtrue)
AM_CONDITIONAL(USE_UNITY, test x$unity = xtrue)
@ -1713,6 +1716,7 @@ AC_CONFIG_FILES([
src/libcharon/plugins/socket_dynamic/Makefile
src/libcharon/plugins/socket_win/Makefile
src/libcharon/plugins/connmark/Makefile
src/libcharon/plugins/forecast/Makefile
src/libcharon/plugins/farp/Makefile
src/libcharon/plugins/smp/Makefile
src/libcharon/plugins/sql/Makefile

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@ -216,6 +216,13 @@ if MONOLITHIC
endif
endif
if USE_FORECAST
SUBDIRS += plugins/forecast
if MONOLITHIC
libcharon_la_LIBADD += plugins/forecast/libstrongswan-forecast.la
endif
endif
if USE_FARP
SUBDIRS += plugins/farp
if MONOLITHIC

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@ -0,0 +1,21 @@
AM_CPPFLAGS = \
-I$(top_srcdir)/src/libstrongswan \
-I$(top_srcdir)/src/libhydra \
-I$(top_srcdir)/src/libcharon
AM_CFLAGS = \
$(PLUGIN_CFLAGS)
if MONOLITHIC
noinst_LTLIBRARIES = libstrongswan-forecast.la
else
plugin_LTLIBRARIES = libstrongswan-forecast.la
endif
libstrongswan_forecast_la_SOURCES = \
forecast_listener.h forecast_listener.c \
forecast_forwarder.h forecast_forwarder.c \
forecast_plugin.h forecast_plugin.c
libstrongswan_forecast_la_LDFLAGS = -module -avoid-version
libstrongswan_forecast_la_LIBADD = -lip4tc

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@ -0,0 +1,496 @@
/*
* Copyright (C) 2010-2014 Martin Willi
* Copyright (C) 2010-2014 revosec AG
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
*
* 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.
*/
#include "forecast_forwarder.h"
#include <errno.h>
#include <unistd.h>
#include <netinet/ip.h>
#include <netinet/udp.h>
#include <linux/socket.h>
#include <netinet/if_ether.h>
#include <linux/if_packet.h>
#include <linux/filter.h>
#include <sys/ioctl.h>
#include <ifaddrs.h>
#include <net/if.h>
#include <hydra.h>
#include <daemon.h>
#include <threading/thread.h>
#include <processing/jobs/callback_job.h>
#define BOOTP_SERVER_PORT 67
#define BOOTP_CLIENT_PORT 68
typedef struct private_forecast_forwarder_t private_forecast_forwarder_t;
typedef struct private_kernel_listener_t private_kernel_listener_t;
/**
* Private data of registered kernel listener
*/
struct private_kernel_listener_t {
/**
* Implements kernel_listener_t
*/
kernel_listener_t listener;
/**
* Listener that knows active addresses
*/
forecast_listener_t *fc;
/**
* current broadcast address of internal network
*/
u_int32_t broadcast;
/**
* LAN interface index
*/
int ifindex;
/**
* Packet socket
*/
int pkt;
/**
* RAW socket
*/
int raw;
};
/**
* Private data of an forecast_forwarder_t object.
*/
struct private_forecast_forwarder_t {
/**
* Public forecast_forwarder_t interface.
*/
forecast_forwarder_t public;
/**
* Public kernel_listener_t interface.
*/
private_kernel_listener_t kernel;
};
/**
* Send a broadcast/multicast packet to a network
*/
static void send_net(private_forecast_forwarder_t *this,
struct sockaddr_ll *addr, void *buf, size_t len)
{
if (sendto(this->kernel.pkt, buf, len, 0,
(struct sockaddr*)addr, sizeof(*addr)) != len)
{
DBG1(DBG_NET, "forecast send_net() failed: %s", strerror(errno));
}
}
/**
* Send a broadcast/multicast packet to a peer
*/
static void send_peer(private_forecast_forwarder_t *this, u_int32_t dst,
void *buf, size_t len, int mark)
{
struct sockaddr_in addr = {
.sin_family = AF_INET,
.sin_addr.s_addr = dst,
};
if (setsockopt(this->kernel.raw, SOL_SOCKET, SO_MARK,
&mark, sizeof(mark)) != 0)
{
DBG1(DBG_NET, "forecast setting SO_MARK failed: %s", strerror(errno));
}
if (sendto(this->kernel.raw, buf, len, 0,
(struct sockaddr*)&addr, sizeof(addr)) != len)
{
DBG1(DBG_NET, "forecast send_peer() failed: %s", strerror(errno));
}
}
/**
* Check if an IP packet is BOOTP/DHCP
*/
static bool is_bootp(void *buf, size_t len)
{
struct __attribute__((__packed__)) {
struct iphdr ip;
struct udphdr udp;
} *pkt = buf;
if (len > sizeof(*pkt))
{
if (ntohs(pkt->udp.source) == BOOTP_CLIENT_PORT &&
ntohs(pkt->udp.dest) == BOOTP_SERVER_PORT)
{
return TRUE;
}
if (ntohs(pkt->udp.source) == BOOTP_SERVER_PORT &&
ntohs(pkt->udp.dest) == BOOTP_CLIENT_PORT)
{
return TRUE;
}
}
return FALSE;
}
/**
* Broadcast/Multicast receiver
*/
static bool receive_casts(private_forecast_forwarder_t *this)
{
struct __attribute__((packed)) {
struct iphdr hdr;
char data[2048];
} buf;
char *type;
ssize_t len;
u_int mark, origin = 0;
host_t *src, *dst;
traffic_selector_t *ts;
enumerator_t *enumerator;
struct sockaddr_ll addr;
socklen_t alen = sizeof(addr);
bool reinject;
len = recvfrom(this->kernel.pkt, &buf, sizeof(buf), MSG_DONTWAIT,
(struct sockaddr*)&addr, &alen);
if (len < 0)
{
if (errno != EAGAIN && errno != EWOULDBLOCK)
{
DBG1(DBG_NET, "receiving from forecast socket failed: %s",
strerror(errno));
}
return TRUE;
}
else if (len < sizeof(struct iphdr))
{
DBG1(DBG_NET, "received short forecast packet: %zd bytes", len);
return TRUE;
}
if (is_bootp(&buf, len))
{ /* don't forward DHCP broadcasts */
return TRUE;
}
src = host_create_from_chunk(AF_INET, chunk_from_thing(buf.hdr.saddr), 0);
dst = host_create_from_chunk(AF_INET, chunk_from_thing(buf.hdr.daddr), 0);
/* create valid broadcast/multicast MAC to send out */
if (IN_MULTICAST(ntohl(buf.hdr.daddr)))
{
type = "multi";
ETHER_MAP_IP_MULTICAST(&buf.hdr.daddr, addr.sll_addr);
}
else
{
type = "broad";
memset(&addr.sll_addr, 0xFF, sizeof(addr.sll_addr));
}
DBG2(DBG_NET, "forecast intercepted packet: %H to %H", src, dst);
/* find mark of originating tunnel */
enumerator = this->kernel.fc->create_enumerator(this->kernel.fc, FALSE);
while (enumerator->enumerate(enumerator, &ts, &mark, &reinject))
{
if (ts->includes(ts, src))
{
origin = mark;
break;
}
}
enumerator->destroy(enumerator);
/* send packet over all tunnels, but not the packets origin */
enumerator = this->kernel.fc->create_enumerator(this->kernel.fc, FALSE);
while (enumerator->enumerate(enumerator, &ts, &mark, &reinject))
{
if (ts->includes(ts, dst))
{
if ((reinject && origin != mark) || origin == 0)
{
DBG2(DBG_NET, "forwarding a %H %scast from %H to peer %R (%u)",
dst, type, src, ts, mark);
send_peer(this, buf.hdr.daddr, &buf, len, mark);
}
}
}
enumerator->destroy(enumerator);
if (origin)
{
/* forward broadcast/multicast from client to network */
DBG2(DBG_NET, "forwarding a %H %scast from peer %H to internal network",
dst, type, src);
addr.sll_ifindex = this->kernel.ifindex;
send_net(this, &addr, &buf, len);
}
dst->destroy(dst);
src->destroy(src);
return TRUE;
}
/**
* Join a multicast group
*/
static void join_group(private_kernel_listener_t *this, char *group,
struct sockaddr *addr)
{
struct sockaddr_in *in;
struct ip_mreqn mreq;
host_t *host;
host = host_create_from_string(group, 0);
if (host)
{
memset(&mreq, 0, sizeof(mreq));
memcpy(&mreq.imr_multiaddr.s_addr, host->get_address(host).ptr, 4);
if (addr->sa_family == AF_INET)
{
in = (struct sockaddr_in*)addr;
memcpy(&mreq.imr_address, &in->sin_addr.s_addr,
sizeof(in->sin_addr.s_addr));
}
mreq.imr_ifindex = this->ifindex;
if (setsockopt(this->raw, IPPROTO_IP, IP_ADD_MEMBERSHIP,
&mreq, sizeof(mreq)) == -1)
{
if (errno != EADDRINUSE)
{
DBG1(DBG_NET, "forecast multicast join to %s failed: %s",
group, strerror(errno));
}
}
else
{
DBG2(DBG_NET, "forwarding multicast group %s", group);
}
host->destroy(host);
}
}
/**
* (Re-)Join all multicast groups we want to forward
*/
static void join_groups(private_kernel_listener_t *this, struct sockaddr *addr)
{
enumerator_t *enumerator;
char *groups, *group;
static char *def =
"224.0.0.1," /* host multicast */
"224.0.0.22," /* IGMP */
"224.0.0.251," /* mDNS */
"224.0.0.252," /* LLMNR */
"239.255.255.250"; /* SSDP/WS-discovery */
groups = lib->settings->get_str(lib->settings,
"%s.plugins.forecast.groups", def, lib->ns);
DBG1(DBG_CFG, "joining forecast multicast groups: %s", groups);
enumerator = enumerator_create_token(groups, ",", " ");
while (enumerator->enumerate(enumerator, &group))
{
join_group(this, group, addr);
}
enumerator->destroy(enumerator);
}
/**
* Attach the socket filter to the socket
*/
static bool attach_filter(int fd, u_int32_t broadcast)
{
struct sock_filter filter_code[] = {
/* destination address: is ... */
BPF_STMT(BPF_LD+BPF_W+BPF_ABS, offsetof(struct iphdr, daddr)),
/* broadcast, as received from the local network */
BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, ntohl(broadcast), 4, 0),
/* broadcast, as Win7 sends them */
BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, 0xFFFFFFFF, 3, 0),
/* any multicast, 224.0.0.0/4 */
BPF_STMT(BPF_ALU+BPF_AND+BPF_K, 0xF0000000),
BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, 0xE0000000, 1, 0),
BPF_STMT(BPF_RET+BPF_K, 0),
BPF_STMT(BPF_LD+BPF_W+BPF_LEN, 0),
BPF_STMT(BPF_RET+BPF_A, 0),
};
struct sock_fprog filter = {
sizeof(filter_code) / sizeof(struct sock_filter),
filter_code,
};
if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER,
&filter, sizeof(filter)) < 0)
{
DBG1(DBG_NET, "installing forecast PACKET socket filter failed: %s",
strerror(errno));
return FALSE;
}
return TRUE;
}
/**
* Get the interface index of an interface name
*/
static int get_ifindex(private_kernel_listener_t *this, char *ifname)
{
struct ifreq ifr = {};
strncpy(ifr.ifr_name, ifname, IFNAMSIZ);
if (ioctl(this->raw, SIOCGIFINDEX, &ifr) == 0)
{
return ifr.ifr_ifindex;
}
return 0;
}
/**
* Set up the interface for broad/multicast forwarding
*/
static void setup_interface(private_kernel_listener_t *this)
{
struct ifaddrs *addrs, *current;
struct sockaddr_in *in;
host_t *host;
char *name;
name = lib->settings->get_str(lib->settings,
"%s.plugins.forecast.interface", NULL, lib->ns);
if (getifaddrs(&addrs) == 0)
{
for (current = addrs; current; current = current->ifa_next)
{
if (name && !streq(name, current->ifa_name))
{
continue;
}
if (current->ifa_flags & IFF_BROADCAST &&
current->ifa_broadaddr &&
current->ifa_broadaddr->sa_family == AF_INET)
{
DBG1(DBG_NET, "using forecast interface %s", current->ifa_name);
this->ifindex = get_ifindex(this, current->ifa_name);
in = (struct sockaddr_in*)current->ifa_broadaddr;
attach_filter(this->pkt, in->sin_addr.s_addr);
join_groups(this, current->ifa_addr);
host = host_create_from_sockaddr(current->ifa_broadaddr);
if (host)
{
this->fc->set_broadcast(this->fc, host);
host->destroy(host);
}
break;
}
}
}
freeifaddrs(addrs);
}
METHOD(kernel_listener_t, roam, bool,
private_kernel_listener_t *this, bool address)
{
if (address)
{
setup_interface(this);
}
return TRUE;
}
METHOD(forecast_forwarder_t, destroy, void,
private_forecast_forwarder_t *this)
{
if (this->kernel.raw != -1)
{
close(this->kernel.raw);
}
if (this->kernel.pkt != -1)
{
lib->watcher->remove(lib->watcher, this->kernel.pkt);
close(this->kernel.pkt);
}
hydra->kernel_interface->remove_listener(hydra->kernel_interface,
&this->kernel.listener);
free(this);
}
/**
* See header
*/
forecast_forwarder_t *forecast_forwarder_create(forecast_listener_t *listener)
{
private_forecast_forwarder_t *this;
int on = 1;
INIT(this,
.public = {
.destroy = _destroy,
},
.kernel = {
.listener = {
.roam = _roam,
},
.raw = -1,
.pkt = -1,
.fc = listener,
},
);
this->kernel.pkt = socket(AF_PACKET, SOCK_DGRAM, htons(ETH_P_IP));
if (this->kernel.pkt == -1)
{
DBG1(DBG_NET, "opening PACKET socket failed: %s", strerror(errno));
destroy(this);
return NULL;
}
this->kernel.raw = socket(AF_INET, SOCK_RAW, IPPROTO_UDP);
if (this->kernel.raw == -1)
{
DBG1(DBG_NET, "opening RAW socket failed: %s", strerror(errno));
destroy(this);
return NULL;
}
if (setsockopt(this->kernel.raw, IPPROTO_IP, IP_HDRINCL,
&on, sizeof(on)) == -1)
{
DBG1(DBG_NET, "forecast socket HDRINCL failed: %s", strerror(errno));
destroy(this);
return NULL;
}
if (setsockopt(this->kernel.raw, SOL_SOCKET, SO_BROADCAST,
&on, sizeof(on)) == -1)
{
DBG1(DBG_NET, "forecast socket BROADCAST failed: %s", strerror(errno));
destroy(this);
return NULL;
}
setup_interface(&this->kernel);
hydra->kernel_interface->add_listener(hydra->kernel_interface,
&this->kernel.listener);
lib->watcher->add(lib->watcher, this->kernel.pkt, WATCHER_READ,
(watcher_cb_t)receive_casts, this);
return &this->public;
}

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@ -0,0 +1,47 @@
/*
* Copyright (C) 2010-2014 Martin Willi
* Copyright (C) 2010-2014 revosec AG
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
*
* 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.
*/
/**
* @defgroup forecast_forwarder forecast_forwarder
* @{ @ingroup forecast
*/
#ifndef FORECAST_FORWARDER_H_
#define FORECAST_FORWARDER_H_
#include "forecast_listener.h"
typedef struct forecast_forwarder_t forecast_forwarder_t;
/**
* Broadcast/Multicast sniffer and forwarder.
*/
struct forecast_forwarder_t {
/**
* Destroy a forecast_forwarder_t.
*/
void (*destroy)(forecast_forwarder_t *this);
};
/**
* Create a forecast_forwarder instance.
*
* @param listener listener to check for addresses to forward to
* @return forwarder instance
*/
forecast_forwarder_t *forecast_forwarder_create(forecast_listener_t *listener);
#endif /** FORECAST_FORWARDER_H_ @}*/

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@ -0,0 +1,680 @@
/*
* Copyright (C) 2010-2014 Martin Willi
* Copyright (C) 2010-2014 revosec AG
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
*
* 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.
*/
#include "forecast_listener.h"
#include <errno.h>
#include <libiptc/libiptc.h>
#include <linux/netfilter/xt_MARK.h>
#include <linux/netfilter/xt_esp.h>
#include <daemon.h>
#include <collections/array.h>
#include <collections/hashtable.h>
#include <threading/rwlock.h>
typedef struct private_forecast_listener_t private_forecast_listener_t;
/**
* Private data of an forecast_listener_t object.
*/
struct private_forecast_listener_t {
/**
* Public forecast_listener_t interface.
*/
forecast_listener_t public;
/**
* List of entries
*/
linked_list_t *entries;
/**
* RWlock for IP list
*/
rwlock_t *lock;
/**
* Configs we do reinjection
*/
char *reinject_configs;
/**
* Broadcast address on LAN interface, network order
*/
u_int32_t broadcast;
};
/**
* Hashtable entry
*/
typedef struct {
/** local traffic selectors */
array_t *lts;
/** remote traffic selectors */
array_t *rts;
/** firewall mark used by CHILD_SA */
u_int mark;
/** local IKE_SA endpoint */
host_t *lhost;
/** remote IKE_SA endpoint */
host_t *rhost;
/** inbound SPI */
u_int32_t spi;
/** use UDP encapsulation */
bool encap;
/** wheter we should allow reencapsulation of IPsec received forecasts */
bool reinject;
/** broadcast address used for that entry */
u_int32_t broadcast;
} entry_t;
/**
* Destroy an entry
*/
static void entry_destroy(entry_t *entry)
{
if (entry)
{
entry->lhost->destroy(entry->lhost);
entry->rhost->destroy(entry->rhost);
array_destroy_offset(entry->lts, offsetof(traffic_selector_t, destroy));
array_destroy_offset(entry->rts, offsetof(traffic_selector_t, destroy));
free(entry);
}
}
/**
* Convert an (IPv4) traffic selector to an address and mask
*/
static bool ts2in(traffic_selector_t *ts,
struct in_addr *addr, struct in_addr *mask)
{
u_int8_t bits;
host_t *net;
if (ts->get_type(ts) == TS_IPV4_ADDR_RANGE &&
ts->to_subnet(ts, &net, &bits))
{
memcpy(&addr->s_addr, net->get_address(net).ptr, 4);
net->destroy(net);
mask->s_addr = htonl(0xffffffffU << (32 - bits));
return TRUE;
}
return FALSE;
}
/**
* Convert an (IPv4) host to an address with mask
*/
static bool host2in(host_t *host, struct in_addr *addr, struct in_addr *mask)
{
if (host->get_family(host) == AF_INET)
{
memcpy(&addr->s_addr, host->get_address(host).ptr, 4);
mask->s_addr = ~0;
return TRUE;
}
return FALSE;
}
/**
* Add or remove a rule to/from the specified chain
*/
static bool manage_rule(struct iptc_handle *ipth, const char *chain,
bool add, struct ipt_entry *e)
{
if (add)
{
if (!iptc_insert_entry(chain, e, 0, ipth))
{
DBG1(DBG_CFG, "appending %s rule failed: %s",
chain, iptc_strerror(errno));
return FALSE;
}
}
else
{
if (!iptc_delete_entry(chain, e, "", ipth))
{
DBG1(DBG_CFG, "deleting %s rule failed: %s",
chain, iptc_strerror(errno));
return FALSE;
}
}
return TRUE;
}
/**
* Add rule marking UDP-encapsulated ESP packets to match the correct policy
*/
static bool manage_pre_esp_in_udp(struct iptc_handle *ipth,
entry_t *entry, bool add)
{
struct {
struct ipt_entry e;
struct ipt_entry_match m;
struct xt_udp udp;
struct ipt_entry_target t;
struct xt_mark_tginfo2 tm;
} ipt = {
.e = {
.target_offset = XT_ALIGN(sizeof(ipt.e) + sizeof(ipt.m) +
sizeof(ipt.udp)),
.next_offset = sizeof(ipt),
.ip = {
.proto = IPPROTO_UDP,
},
},
.m = {
.u = {
.user = {
.match_size = XT_ALIGN(sizeof(ipt.m) + sizeof(ipt.udp)),
.name = "udp",
},
},
},
.udp = {
.spts = {
entry->rhost->get_port(entry->rhost),
entry->rhost->get_port(entry->lhost)
},
.dpts = {
entry->lhost->get_port(entry->lhost),
entry->lhost->get_port(entry->lhost)
},
},
.t = {
.u = {
.user = {
.target_size = XT_ALIGN(sizeof(ipt.t) + sizeof(ipt.tm)),
.name = "MARK",
.revision = 2,
},
},
},
.tm = {
.mark = entry->mark,
.mask = ~0,
},
};
if (!host2in(entry->lhost, &ipt.e.ip.dst, &ipt.e.ip.dmsk) ||
!host2in(entry->rhost, &ipt.e.ip.src, &ipt.e.ip.smsk))
{
return FALSE;
}
return manage_rule(ipth, "PREROUTING", add, &ipt.e);
}
/**
* Add rule marking non-encapsulated ESP packets to match the correct policy
*/
static bool manage_pre_esp(struct iptc_handle *ipth, entry_t *entry, bool add)
{
struct {
struct ipt_entry e;
struct ipt_entry_match m;
struct xt_esp esp;
struct ipt_entry_target t;
struct xt_mark_tginfo2 tm;
} ipt = {
.e = {
.target_offset = XT_ALIGN(sizeof(ipt.e) + sizeof(ipt.m) +
sizeof(ipt.esp)),
.next_offset = sizeof(ipt),
.ip = {
.proto = IPPROTO_ESP,
},
},
.m = {
.u = {
.user = {
.match_size = XT_ALIGN(sizeof(ipt.m) + sizeof(ipt.esp)),
.name = "esp",
},
},
},
.esp = {
.spis = { htonl(entry->spi), htonl(entry->spi) },
},
.t = {
.u = {
.user = {
.target_size = XT_ALIGN(sizeof(ipt.t) + sizeof(ipt.tm)),
.name = "MARK",
.revision = 2,
},
},
},
.tm = {
.mark = entry->mark,
.mask = ~0,
},
};
if (!host2in(entry->lhost, &ipt.e.ip.dst, &ipt.e.ip.dmsk) ||
!host2in(entry->rhost, &ipt.e.ip.src, &ipt.e.ip.smsk))
{
return FALSE;
}
return manage_rule(ipth, "PREROUTING", add, &ipt.e);
}
/**
* Add rule marking ESP packets to match the correct policy
*/
static bool manage_pre(struct iptc_handle *ipth, entry_t *entry, bool add)
{
if (entry->encap)
{
return manage_pre_esp_in_udp(ipth, entry, add);
}
return manage_pre_esp(ipth, entry, add);
}
/**
* Add rule handling outbound traffic to use correct mark
*/
static bool manage_out(struct iptc_handle *ipth, entry_t *entry, bool add)
{
struct {
struct ipt_entry e;
struct ipt_entry_target t;
struct xt_mark_tginfo2 m;
} ipt = {
.e = {
.target_offset = XT_ALIGN(sizeof(ipt.e)),
.next_offset = sizeof(ipt),
},
.t = {
.u.user.target_size = XT_ALIGN(sizeof(ipt.t) + sizeof(ipt.m)),
.u.user.name = "MARK",
.u.user.revision = 2,
},
.m = {
.mark = entry->mark,
.mask = ~0,
},
};
enumerator_t *enumerator;
traffic_selector_t *ts;
enumerator = array_create_enumerator(entry->rts);
while (enumerator->enumerate(enumerator, &ts))
{
if (!ts2in(ts, &ipt.e.ip.dst, &ipt.e.ip.dmsk))
{
continue;
}
if (ipt.e.ip.dst.s_addr == 0xffffffff ||
ipt.e.ip.dst.s_addr == entry->broadcast ||
memeq(&ipt.e.ip.dst.s_addr, "\xe0", 1))
{
/* skip broadcast/multicast selectors, they are shared and the mark
* is set by the socket we use for reinjection */
continue;
}
if (!manage_rule(ipth, "PREROUTING", add, &ipt.e) ||
!manage_rule(ipth, "OUTPUT", add, &ipt.e))
{
enumerator->destroy(enumerator);
return FALSE;
}
}
enumerator->destroy(enumerator);
return TRUE;
}
/**
* Check if config is whitelisted to reinject traffic
*/
static bool is_reinject_config(private_forecast_listener_t *this, char *name)
{
enumerator_t *enumerator;
bool reinject = FALSE;
char *token;
enumerator = enumerator_create_token(this->reinject_configs, ",", " ");
while (enumerator->enumerate(enumerator, &token))
{
if (streq(token, name))
{
reinject = TRUE;
break;
}
}
enumerator->destroy(enumerator);
return reinject;
}
/**
* Add rules and entry for given CHILD_SA
*/
static bool add_entry(private_forecast_listener_t *this,
struct iptc_handle *ipth, host_t *lhost, host_t *rhost,
child_sa_t *child_sa, bool encap)
{
enumerator_t *enumerator;
traffic_selector_t *ts;
entry_t *entry;
INIT(entry,
.lts = array_create(0, 0),
.rts = array_create(0, 0),
.lhost = lhost->clone(lhost),
.rhost = rhost->clone(rhost),
.spi = child_sa->get_spi(child_sa, TRUE),
.encap = encap,
.mark = child_sa->get_mark(child_sa, TRUE).value,
.reinject = is_reinject_config(this, child_sa->get_name(child_sa)),
.broadcast = this->broadcast,
);
enumerator = child_sa->create_ts_enumerator(child_sa, TRUE);
while (enumerator->enumerate(enumerator, &ts))
{
array_insert(entry->lts, ARRAY_TAIL, ts->clone(ts));
}
enumerator->destroy(enumerator);
enumerator = child_sa->create_ts_enumerator(child_sa, FALSE);
while (enumerator->enumerate(enumerator, &ts))
{
array_insert(entry->rts, ARRAY_TAIL, ts->clone(ts));
}
enumerator->destroy(enumerator);
if (manage_pre(ipth, entry, TRUE) &&
manage_out(ipth, entry, TRUE))
{
this->lock->write_lock(this->lock);
this->entries->insert_last(this->entries, entry);
this->lock->unlock(this->lock);
return TRUE;
}
entry_destroy(entry);
return FALSE;
}
/**
* Remove an entry and rules for a given mark
*/
static bool remove_entry(private_forecast_listener_t *this,
struct iptc_handle *ipth, child_sa_t *child_sa)
{
enumerator_t *enumerator;
entry_t *entry;
bool done = FALSE;
this->lock->write_lock(this->lock);
enumerator = this->entries->create_enumerator(this->entries);
while (enumerator->enumerate(enumerator, &entry))
{
if (entry->mark == child_sa->get_mark(child_sa, TRUE).value)
{
this->entries->remove_at(this->entries, enumerator);
if (manage_pre(ipth, entry, FALSE) &&
manage_out(ipth, entry, FALSE))
{
done = TRUE;
}
entry_destroy(entry);
break;
}
}
enumerator->destroy(enumerator);
this->lock->unlock(this->lock);
return done;
}
/**
* Initialize iptables handle, log error
*/
static struct iptc_handle* init_handle()
{
struct iptc_handle *ipth;
ipth = iptc_init("mangle");
if (ipth)
{
return ipth;
}
DBG1(DBG_CFG, "initializing iptables failed: %s", iptc_strerror(errno));
return NULL;
}
/**
* Commit iptables rules, log error
*/
static bool commit_handle(struct iptc_handle *ipth)
{
if (iptc_commit(ipth))
{
return TRUE;
}
DBG1(DBG_CFG, "forecast iptables commit failed: %s", iptc_strerror(errno));
return FALSE;
}
/**
* Check if we should handle the given CHILD_SA
*/
static bool handle_sa(child_sa_t *child_sa)
{
return child_sa->get_mark(child_sa, TRUE).value &&
child_sa->get_mark(child_sa, FALSE).value;
}
METHOD(listener_t, child_updown, bool,
private_forecast_listener_t *this, ike_sa_t *ike_sa, child_sa_t *child_sa,
bool up)
{
struct iptc_handle *ipth;
host_t *lhost, *rhost;
bool encap;
lhost = ike_sa->get_my_host(ike_sa);
rhost = ike_sa->get_other_host(ike_sa);
encap = child_sa->has_encap(child_sa);
if (handle_sa(child_sa))
{
ipth = init_handle();
if (ipth)
{
if (up)
{
if (add_entry(this, ipth, lhost, rhost, child_sa, encap))
{
commit_handle(ipth);
}
}
else
{
if (remove_entry(this, ipth, child_sa))
{
commit_handle(ipth);
}
}
iptc_free(ipth);
}
}
return TRUE;
}
METHOD(listener_t, child_rekey, bool,
private_forecast_listener_t *this, ike_sa_t *ike_sa,
child_sa_t *old, child_sa_t *new)
{
struct iptc_handle *ipth;;
host_t *lhost, *rhost;
lhost = ike_sa->get_my_host(ike_sa);
rhost = ike_sa->get_other_host(ike_sa);
if (handle_sa(old))
{
ipth = init_handle();
if (ipth)
{
if (remove_entry(this, ipth, old) &&
add_entry(this, ipth, lhost, rhost, new, new->has_encap(new)))
{
commit_handle(ipth);
}
iptc_free(ipth);
}
}
return TRUE;
}
METHOD(listener_t, ike_update, bool,
private_forecast_listener_t *this, ike_sa_t *ike_sa,
bool local, host_t *new)
{
struct iptc_handle *ipth;
enumerator_t *enumerator;
child_sa_t *child_sa;
host_t *lhost, *rhost;
bool encap;
if (local)
{
lhost = new;
rhost = ike_sa->get_other_host(ike_sa);
}
else
{
lhost = ike_sa->get_my_host(ike_sa);
rhost = new;
}
/* during ike_update(), has_encap() on the CHILD_SA has not yet been
* updated, but shows the old state. */
encap = ike_sa->has_condition(ike_sa, COND_NAT_ANY);
enumerator = ike_sa->create_child_sa_enumerator(ike_sa);
while (enumerator->enumerate(enumerator, &child_sa))
{
if (handle_sa(child_sa))
{
ipth = init_handle();
if (ipth)
{
if (remove_entry(this, ipth, child_sa) &&
add_entry(this, ipth, lhost, rhost, child_sa, encap))
{
commit_handle(ipth);
}
iptc_free(ipth);
}
}
}
enumerator->destroy(enumerator);
return TRUE;
}
/**
* Filter to map entries to ts/mark
*/
static bool ts_filter(entry_t *entry, traffic_selector_t **ts,
traffic_selector_t **out, void *dummy, u_int32_t *mark,
void *dummy2, bool *reinject)
{
*out = *ts;
*mark = entry->mark;
*reinject = entry->reinject;
return TRUE;
}
/**
* Create inner enumerator over local traffic selectors
*/
static enumerator_t* create_inner_local(entry_t *entry, rwlock_t *lock)
{
return enumerator_create_filter(array_create_enumerator(entry->lts),
(void*)ts_filter, entry, NULL);
}
/**
* Create inner enumerator over remote traffic selectors
*/
static enumerator_t* create_inner_remote(entry_t *entry, rwlock_t *lock)
{
return enumerator_create_filter(array_create_enumerator(entry->rts),
(void*)ts_filter, entry, NULL);
}
METHOD(forecast_listener_t, create_enumerator, enumerator_t*,
private_forecast_listener_t *this, bool local)
{
this->lock->read_lock(this->lock);
return enumerator_create_nested(
this->entries->create_enumerator(this->entries),
(void*)(local ? create_inner_local : create_inner_remote),
this->lock, (void*)this->lock->unlock);
}
METHOD(forecast_listener_t, set_broadcast, void,
private_forecast_listener_t *this, host_t *bcast)
{
if (bcast->get_family(bcast) == AF_INET)
{
struct sockaddr_in *in;
in = bcast->get_sockaddr(bcast);
this->broadcast = in->sin_addr.s_addr;
}
}
METHOD(forecast_listener_t, destroy, void,
private_forecast_listener_t *this)
{
this->entries->destroy(this->entries);
this->lock->destroy(this->lock);
free(this);
}
/**
* See header
*/
forecast_listener_t *forecast_listener_create()
{
private_forecast_listener_t *this;
INIT(this,
.public = {
.listener = {
.ike_update = _ike_update,
.child_updown = _child_updown,
.child_rekey = _child_rekey,
},
.create_enumerator = _create_enumerator,
.set_broadcast = _set_broadcast,
.destroy = _destroy,
},
.entries = linked_list_create(),
.lock = rwlock_create(RWLOCK_TYPE_DEFAULT),
.reinject_configs = lib->settings->get_str(lib->settings,
"%s.plugins.forecast.reinject", "", lib->ns),
);
return &this->public;
}

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/*
* Copyright (C) 2010-2014 Martin Willi
* Copyright (C) 2010-2014 revosec AG
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
*
* 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.
*/
/**
* @defgroup forecast_listener forecast_listener
* @{ @ingroup forecast
*/
#ifndef FORECAST_LISTENER_H_
#define FORECAST_LISTENER_H_
#include <bus/listeners/listener.h>
typedef struct forecast_listener_t forecast_listener_t;
/**
* Listener to register the set of IPs we forward received multi/broadcasts to.
*/
struct forecast_listener_t {
/**
* Implements listener_t interface.
*/
listener_t listener;
/**
* Create an enumerator over active tunnels.
*
* The enumerator enumerates over local or remote traffic selectors,
* associated firewall marks and if decasulated packets should get
* reinjected into other tunnels.
*
* @param local TRUE to enumerate local, FALSE to enumerate remote TS
* @return enumerator over (traffic_selector_t*, u_int, bool)
*/
enumerator_t* (*create_enumerator)(forecast_listener_t *this, bool local);
/**
* Set the broadcast address of the LAN interface.
*
* @param bcast broadcast address
*/
void (*set_broadcast)(forecast_listener_t *this, host_t *bcast);
/**
* Destroy a forecast_listener_t.
*/
void (*destroy)(forecast_listener_t *this);
};
/**
* Create a forecast_listener instance.
*/
forecast_listener_t *forecast_listener_create();
#endif /** FORECAST_LISTENER_H_ @}*/

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/*
* Copyright (C) 2010-2014 Martin Willi
* Copyright (C) 2010-2014 revosec AG
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
*
* 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.
*/
#include "forecast_plugin.h"
#include "forecast_listener.h"
#include "forecast_forwarder.h"
#include <daemon.h>
typedef struct private_forecast_plugin_t private_forecast_plugin_t;
/**
* Private data of forecast plugin
*/
struct private_forecast_plugin_t {
/**
* implements plugin interface
*/
forecast_plugin_t public;
/**
* Listener registering active tunnels
*/
forecast_listener_t *listener;
/**
* Broadcast/Multicast sniffer and forwarder
*/
forecast_forwarder_t *forwarder;
};
METHOD(plugin_t, get_name, char*,
private_forecast_plugin_t *this)
{
return "forecast";
}
/**
* Register plugin features
*/
static bool register_forecast(private_forecast_plugin_t *this,
plugin_feature_t *feature, bool reg, void *data)
{
if (reg)
{
this->forwarder = forecast_forwarder_create(this->listener);
if (!this->forwarder)
{
return FALSE;
}
charon->bus->add_listener(charon->bus, &this->listener->listener);
}
else
{
charon->bus->remove_listener(charon->bus, &this->listener->listener);
this->forwarder->destroy(this->forwarder);
}
return TRUE;
}
METHOD(plugin_t, get_features, int,
private_forecast_plugin_t *this, plugin_feature_t *features[])
{
static plugin_feature_t f[] = {
PLUGIN_CALLBACK((plugin_feature_callback_t)register_forecast, NULL),
PLUGIN_PROVIDE(CUSTOM, "forecast"),
};
*features = f;
return countof(f);
}
METHOD(plugin_t, destroy, void,
private_forecast_plugin_t *this)
{
this->listener->destroy(this->listener);
free(this);
}
/**
* Plugin constructor
*/
plugin_t *forecast_plugin_create()
{
private_forecast_plugin_t *this;
if (!lib->caps->keep(lib->caps, CAP_NET_RAW))
{
DBG1(DBG_NET, "forecast plugin requires CAP_NET_RAW capability");
return NULL;
}
INIT(this,
.public = {
.plugin = {
.get_name = _get_name,
.get_features = _get_features,
.reload = (void*)return_false,
.destroy = _destroy,
},
},
.listener = forecast_listener_create(),
);
return &this->public.plugin;
}

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/*
* Copyright (C) 2010-2014 Martin Willi
* Copyright (C) 2010-2014 revosec AG
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
*
* 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.
*/
/**
* @defgroup forecast forecast
* @ingroup cplugins
*
* @defgroup forecast_plugin forecast_plugin
* @{ @ingroup forecast
*/
#ifndef FORECAST_PLUGIN_H_
#define FORECAST_PLUGIN_H_
#include <plugins/plugin.h>
typedef struct forecast_plugin_t forecast_plugin_t;
/**
* Broadcast/Multicast forwarding plugin.
*/
struct forecast_plugin_t {
/**
* Implements plugin interface.
*/
plugin_t plugin;
};
#endif /** FORECAST_PLUGIN_H_ @}*/