libvirt/src/util/viriptables.c

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/*
* viriptables.c: helper APIs for managing iptables
*
util: make it easier to grab only regular command exit Auditing all callers of virCommandRun and virCommandWait that passed a non-NULL pointer for exit status turned up some interesting observations. Many callers were merely passing a pointer to avoid the overall command dying, but without caring what the exit status was - but these callers would be better off treating a child death by signal as an abnormal exit. Other callers were actually acting on the status, but not all of them remembered to filter by WIFEXITED and convert with WEXITSTATUS; depending on the platform, this can result in a status being reported as 256 times too big. And among those that correctly parse the output, it gets rather verbose. Finally, there were the callers that explicitly checked that the status was 0, and gave their own message, but with fewer details than what virCommand gives for free. So the best idea is to move the complexity out of callers and into virCommand - by default, we return the actual exit status already cleaned through WEXITSTATUS and treat signals as a failed command; but the few callers that care can ask for raw status and act on it themselves. * src/util/vircommand.h (virCommandRawStatus): New prototype. * src/libvirt_private.syms (util/command.h): Export it. * docs/internals/command.html.in: Document it. * src/util/vircommand.c (virCommandRawStatus): New function. (virCommandWait): Adjust semantics. * tests/commandtest.c (test1): Test it. * daemon/remote.c (remoteDispatchAuthPolkit): Adjust callers. * src/access/viraccessdriverpolkit.c (virAccessDriverPolkitCheck): Likewise. * src/fdstream.c (virFDStreamCloseInt): Likewise. * src/lxc/lxc_process.c (virLXCProcessStart): Likewise. * src/qemu/qemu_command.c (qemuCreateInBridgePortWithHelper): Likewise. * src/xen/xen_driver.c (xenUnifiedXendProbe): Simplify. * tests/reconnect.c (mymain): Likewise. * tests/statstest.c (mymain): Likewise. * src/bhyve/bhyve_process.c (virBhyveProcessStart) (virBhyveProcessStop): Don't overwrite virCommand error. * src/libvirt.c (virConnectAuthGainPolkit): Likewise. * src/openvz/openvz_driver.c (openvzDomainGetBarrierLimit) (openvzDomainSetBarrierLimit): Likewise. * src/util/virebtables.c (virEbTablesOnceInit): Likewise. * src/util/viriptables.c (virIpTablesOnceInit): Likewise. * src/util/virnetdevveth.c (virNetDevVethCreate): Fix debug message. * src/qemu/qemu_capabilities.c (virQEMUCapsInitQMP): Add comment. * src/storage/storage_backend_iscsi.c (virStorageBackendISCSINodeUpdate): Likewise. Signed-off-by: Eric Blake <eblake@redhat.com>
2014-02-20 00:32:19 +00:00
* Copyright (C) 2007-2014 Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* <http://www.gnu.org/licenses/>.
*
* Authors:
* Mark McLoughlin <markmc@redhat.com>
*/
#include <config.h>
#include <stdarg.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include "internal.h"
#include "viriptables.h"
#include "vircommand.h"
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#include "viralloc.h"
#include "virerror.h"
#include "virfile.h"
2012-12-12 17:59:27 +00:00
#include "virlog.h"
#include "virthread.h"
#include "virstring.h"
#include "virutil.h"
network: use firewalld instead of iptables, when available * configure.ac, spec file: firewalld defaults to enabled if dbus is available, otherwise is disabled. If --with_firewalld is explicitly requested and dbus is not available, configure will fail. * bridge_driver: add dbus filters to get the FirewallD1.Reloaded signal and DBus.NameOwnerChanged on org.fedoraproject.FirewallD1. When these are encountered, reload all the iptables reuls of all libvirt's virtual networks (similar to what happens when libvirtd is restarted). * iptables, ebtables: use firewall-cmd's direct passthrough interface when available, otherwise use iptables and ebtables commands. This decision is made once the first time libvirt calls iptables/ebtables, and that decision is maintained for the life of libvirtd. * Note that the nwfilter part of this patch was separated out into another patch by Stefan in V2, so that needs to be revised and re-reviewed as well. ================ All the configure.ac and specfile changes are unchanged from Thomas' V3. V3 re-ran "firewall-cmd --state" every time a new rule was added, which was extremely inefficient. V4 uses VIR_ONCE_GLOBAL_INIT to set up a one-time initialization function. The VIR_ONCE_GLOBAL_INIT(x) macro references a static function called vir(Ip|Eb)OnceInit(), which will then be called the first time that the static function vir(Ip|Eb)TablesInitialize() is called (that function is defined for you by the macro). This is thread-safe, so there is no chance of any race. IMPORTANT NOTE: I've left the VIR_DEBUG messages in these two init functions (one for iptables, on for ebtables) as VIR_WARN so that I don't have to turn on all the other debug message just to see these. Even if this patch doesn't need any other modification, those messages need to be changed to VIR_DEBUG before pushing. This one-time initialization works well. However, I've encountered problems with testing: 1) Whenever I have enabled the firewalld service, *all* attempts to call firewall-cmd from within libvirtd end with firewall-cmd hanging internally somewhere. This is *not* the case if firewall-cmd returns non-0 in response to "firewall-cmd --state" (i.e. *that* command runs and returns to libvirt successfully.) 2) If I start libvirtd while firewalld is stopped, then start firewalld later, this triggers libvirtd to reload its iptables rules, however it also spits out a *ton* of complaints about deletion failing (I suppose because firewalld has nuked all of libvirt's rules). I guess we need to suppress those messages (which is a more annoying problem to fix than you might think, but that's another story). 3) I noticed a few times during this long line of errors that firewalld made a complaint about "Resource Temporarily unavailable. Having libvirtd access iptables commands directly at the same time as firewalld is doing so is apparently problematic. 4) In general, I'm concerned about the "set it once and never change it" method - if firewalld is disabled at libvirtd startup, causing libvirtd to always use iptables/ebtables directly, this won't cause *terrible* problems, but if libvirtd decides to use firewall-cmd and firewalld is later disabled, libvirtd will not be able to recover.
2012-08-14 18:59:52 +00:00
VIR_LOG_INIT("util.iptables");
#define VIR_FROM_THIS VIR_FROM_NONE
enum {
ADD = 0,
REMOVE
};
static void
iptablesInput(virFirewallPtr fw,
virFirewallLayer layer,
const char *iface,
int port,
int action,
int tcp)
{
char portstr[32];
snprintf(portstr, sizeof(portstr), "%d", port);
portstr[sizeof(portstr) - 1] = '\0';
virFirewallAddRule(fw, layer,
"--table", "filter",
action == ADD ? "--insert" : "--delete", "INPUT",
"--in-interface", iface,
"--protocol", tcp ? "tcp" : "udp",
"--destination-port", portstr,
"--jump", "ACCEPT",
NULL);
}
static void
iptablesOutput(virFirewallPtr fw,
virFirewallLayer layer,
const char *iface,
int port,
int action,
int tcp)
{
char portstr[32];
snprintf(portstr, sizeof(portstr), "%d", port);
portstr[sizeof(portstr) - 1] = '\0';
virFirewallAddRule(fw, layer,
"--table", "filter",
action == ADD ? "--insert" : "--delete", "OUTPUT",
"--out-interface", iface,
"--protocol", tcp ? "tcp" : "udp",
"--destination-port", portstr,
"--jump", "ACCEPT",
NULL);
}
/**
* iptablesAddTcpInput:
* @ctx: pointer to the IP table context
* @iface: the interface name
* @port: the TCP port to add
*
* Add an input to the IP table allowing access to the given @port on
* the given @iface interface for TCP packets
*/
void
iptablesAddTcpInput(virFirewallPtr fw,
virFirewallLayer layer,
const char *iface,
int port)
{
iptablesInput(fw, layer, iface, port, ADD, 1);
}
/**
* iptablesRemoveTcpInput:
* @ctx: pointer to the IP table context
* @iface: the interface name
* @port: the TCP port to remove
*
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* Removes an input from the IP table, hence forbidding access to the given
* @port on the given @iface interface for TCP packets
*/
void
iptablesRemoveTcpInput(virFirewallPtr fw,
virFirewallLayer layer,
const char *iface,
int port)
{
iptablesInput(fw, layer, iface, port, REMOVE, 1);
}
/**
* iptablesAddUdpInput:
* @ctx: pointer to the IP table context
* @iface: the interface name
* @port: the UDP port to add
*
* Add an input to the IP table allowing access to the given @port on
* the given @iface interface for UDP packets
*/
void
iptablesAddUdpInput(virFirewallPtr fw,
virFirewallLayer layer,
const char *iface,
int port)
{
iptablesInput(fw, layer, iface, port, ADD, 0);
}
/**
* iptablesRemoveUdpInput:
* @ctx: pointer to the IP table context
* @iface: the interface name
* @port: the UDP port to remove
*
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* Removes an input from the IP table, hence forbidding access to the given
* @port on the given @iface interface for UDP packets
*/
void
iptablesRemoveUdpInput(virFirewallPtr fw,
virFirewallLayer layer,
const char *iface,
int port)
{
return iptablesInput(fw, layer, iface, port, REMOVE, 0);
}
/**
* iptablesAddUdpOutput:
* @ctx: pointer to the IP table context
* @iface: the interface name
* @port: the UDP port to add
*
* Add an output to the IP table allowing access to the given @port from
* the given @iface interface for UDP packets
*/
void
iptablesAddUdpOutput(virFirewallPtr fw,
virFirewallLayer layer,
const char *iface,
int port)
{
iptablesOutput(fw, layer, iface, port, ADD, 0);
}
/**
* iptablesRemoveUdpOutput:
* @ctx: pointer to the IP table context
* @iface: the interface name
* @port: the UDP port to remove
*
* Removes an output from the IP table, hence forbidding access to the given
* @port from the given @iface interface for UDP packets
*/
void
iptablesRemoveUdpOutput(virFirewallPtr fw,
virFirewallLayer layer,
const char *iface,
int port)
{
iptablesOutput(fw, layer, iface, port, REMOVE, 0);
}
static char *iptablesFormatNetwork(virSocketAddr *netaddr,
unsigned int prefix)
{
virSocketAddr network;
VIR_AUTOFREE(char *) netstr = NULL;
char *ret;
if (!(VIR_SOCKET_ADDR_IS_FAMILY(netaddr, AF_INET) ||
VIR_SOCKET_ADDR_IS_FAMILY(netaddr, AF_INET6))) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("Only IPv4 or IPv6 addresses can be used with iptables"));
return NULL;
}
if (virSocketAddrMaskByPrefix(netaddr, prefix, &network) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("Failure to mask address"));
return NULL;
}
netstr = virSocketAddrFormat(&network);
if (!netstr)
return NULL;
ignore_value(virAsprintf(&ret, "%s/%d", netstr, prefix));
return ret;
}
/* Allow all traffic coming from the bridge, with a valid network address
* to proceed to WAN
*/
static int
iptablesForwardAllowOut(virFirewallPtr fw,
virSocketAddr *netaddr,
unsigned int prefix,
const char *iface,
const char *physdev,
int action)
{
VIR_AUTOFREE(char *) networkstr = NULL;
virFirewallLayer layer = VIR_SOCKET_ADDR_FAMILY(netaddr) == AF_INET ?
VIR_FIREWALL_LAYER_IPV4 : VIR_FIREWALL_LAYER_IPV6;
if (!(networkstr = iptablesFormatNetwork(netaddr, prefix)))
return -1;
if (physdev && physdev[0])
virFirewallAddRule(fw, layer,
"--table", "filter",
action == ADD ? "--insert" : "--delete", "FORWARD",
"--source", networkstr,
"--in-interface", iface,
"--out-interface", physdev,
"--jump", "ACCEPT",
NULL);
else
virFirewallAddRule(fw, layer,
"--table", "filter",
action == ADD ? "--insert" : "--delete", "FORWARD",
"--source", networkstr,
"--in-interface", iface,
"--jump", "ACCEPT",
NULL);
return 0;
}
/**
* iptablesAddForwardAllowOut:
* @ctx: pointer to the IP table context
* @network: the source network name
* @iface: the source interface name
* @physdev: the physical output device
*
* Add a rule to the IP table context to allow the traffic for the
* network @network via interface @iface to be forwarded to
* @physdev device. This allow the outbound traffic on a bridge.
*
* Returns 0 in case of success or an error code otherwise
*/
int
iptablesAddForwardAllowOut(virFirewallPtr fw,
virSocketAddr *netaddr,
unsigned int prefix,
const char *iface,
const char *physdev)
{
return iptablesForwardAllowOut(fw, netaddr, prefix, iface, physdev, ADD);
}
/**
* iptablesRemoveForwardAllowOut:
* @ctx: pointer to the IP table context
* @network: the source network name
* @iface: the source interface name
* @physdev: the physical output device
*
* Remove a rule from the IP table context hence forbidding forwarding
* of the traffic for the network @network via interface @iface
* to the @physdev device output. This stops the outbound traffic on a bridge.
*
* Returns 0 in case of success or an error code otherwise
*/
int
iptablesRemoveForwardAllowOut(virFirewallPtr fw,
virSocketAddr *netaddr,
unsigned int prefix,
const char *iface,
const char *physdev)
{
return iptablesForwardAllowOut(fw, netaddr, prefix, iface, physdev, REMOVE);
}
/* Allow all traffic destined to the bridge, with a valid network address
* and associated with an existing connection
*/
static int
iptablesForwardAllowRelatedIn(virFirewallPtr fw,
virSocketAddr *netaddr,
unsigned int prefix,
const char *iface,
const char *physdev,
int action)
{
virFirewallLayer layer = VIR_SOCKET_ADDR_FAMILY(netaddr) == AF_INET ?
VIR_FIREWALL_LAYER_IPV4 : VIR_FIREWALL_LAYER_IPV6;
VIR_AUTOFREE(char *) networkstr = NULL;
if (!(networkstr = iptablesFormatNetwork(netaddr, prefix)))
return -1;
if (physdev && physdev[0])
virFirewallAddRule(fw, layer,
"--table", "filter",
action == ADD ? "--insert" : "--delete", "FORWARD",
"--destination", networkstr,
"--in-interface", physdev,
"--out-interface", iface,
"--match", "conntrack",
"--ctstate", "ESTABLISHED,RELATED",
"--jump", "ACCEPT",
NULL);
else
virFirewallAddRule(fw, layer,
"--table", "filter",
action == ADD ? "--insert" : "--delete", "FORWARD",
"--destination", networkstr,
"--out-interface", iface,
"--match", "conntrack",
"--ctstate", "ESTABLISHED,RELATED",
"--jump", "ACCEPT",
NULL);
return 0;
}
/**
* iptablesAddForwardAllowRelatedIn:
* @ctx: pointer to the IP table context
* @network: the source network name
* @iface: the output interface name
* @physdev: the physical input device or NULL
*
* Add rules to the IP table context to allow the traffic for the
* network @network on @physdev device to be forwarded to
* interface @iface, if it is part of an existing connection.
*
* Returns 0 in case of success or an error code otherwise
*/
int
iptablesAddForwardAllowRelatedIn(virFirewallPtr fw,
virSocketAddr *netaddr,
unsigned int prefix,
const char *iface,
const char *physdev)
{
return iptablesForwardAllowRelatedIn(fw, netaddr, prefix, iface, physdev, ADD);
}
/**
* iptablesRemoveForwardAllowRelatedIn:
* @ctx: pointer to the IP table context
* @network: the source network name
* @iface: the output interface name
* @physdev: the physical input device or NULL
*
* Remove rules from the IP table context hence forbidding the traffic for
* network @network on @physdev device to be forwarded to
* interface @iface, if it is part of an existing connection.
*
* Returns 0 in case of success or an error code otherwise
*/
int
iptablesRemoveForwardAllowRelatedIn(virFirewallPtr fw,
virSocketAddr *netaddr,
unsigned int prefix,
const char *iface,
const char *physdev)
{
return iptablesForwardAllowRelatedIn(fw, netaddr, prefix, iface, physdev, REMOVE);
}
/* Allow all traffic destined to the bridge, with a valid network address
*/
static int
iptablesForwardAllowIn(virFirewallPtr fw,
virSocketAddr *netaddr,
unsigned int prefix,
const char *iface,
const char *physdev,
int action)
{
virFirewallLayer layer = VIR_SOCKET_ADDR_FAMILY(netaddr) == AF_INET ?
VIR_FIREWALL_LAYER_IPV4 : VIR_FIREWALL_LAYER_IPV6;
VIR_AUTOFREE(char *) networkstr = NULL;
if (!(networkstr = iptablesFormatNetwork(netaddr, prefix)))
return -1;
if (physdev && physdev[0])
virFirewallAddRule(fw, layer,
"--table", "filter",
action == ADD ? "--insert" : "--delete", "FORWARD",
"--destination", networkstr,
"--in-interface", physdev,
"--out-interface", iface,
"--jump", "ACCEPT",
NULL);
else
virFirewallAddRule(fw, layer,
"--table", "filter",
action == ADD ? "--insert" : "--delete", "FORWARD",
"--destination", networkstr,
"--out-interface", iface,
"--jump", "ACCEPT",
NULL);
return 0;
}
/**
* iptablesAddForwardAllowIn:
* @ctx: pointer to the IP table context
* @network: the source network name
* @iface: the output interface name
* @physdev: the physical input device or NULL
*
* Add rules to the IP table context to allow the traffic for the
* network @network on @physdev device to be forwarded to
* interface @iface. This allow the inbound traffic on a bridge.
*
* Returns 0 in case of success or an error code otherwise
*/
int
iptablesAddForwardAllowIn(virFirewallPtr fw,
virSocketAddr *netaddr,
unsigned int prefix,
const char *iface,
const char *physdev)
{
return iptablesForwardAllowIn(fw, netaddr, prefix, iface, physdev, ADD);
}
/**
* iptablesRemoveForwardAllowIn:
* @ctx: pointer to the IP table context
* @network: the source network name
* @iface: the output interface name
* @physdev: the physical input device or NULL
*
* Remove rules from the IP table context hence forbidding the traffic for
* network @network on @physdev device to be forwarded to
* interface @iface. This stops the inbound traffic on a bridge.
*
* Returns 0 in case of success or an error code otherwise
*/
int
iptablesRemoveForwardAllowIn(virFirewallPtr fw,
virSocketAddr *netaddr,
unsigned int prefix,
const char *iface,
const char *physdev)
{
return iptablesForwardAllowIn(fw, netaddr, prefix, iface, physdev, REMOVE);
}
/**
* iptablesAddForwardAllowCross:
* @ctx: pointer to the IP table context
* @iface: the input/output interface name
*
* Add rules to the IP table context to allow traffic to cross that
* interface. It allows all traffic between guests on the same bridge
* represented by that interface.
*
* Returns 0 in case of success or an error code otherwise
*/
void
iptablesAddForwardAllowCross(virFirewallPtr fw,
virFirewallLayer layer,
const char *iface)
{
virFirewallAddRule(fw, layer,
"--table", "filter",
"--insert", "FORWARD",
"--in-interface", iface,
"--out-interface", iface,
"--jump", "ACCEPT",
NULL);
}
/**
* iptablesRemoveForwardAllowCross:
* @ctx: pointer to the IP table context
* @iface: the input/output interface name
*
* Remove rules to the IP table context to block traffic to cross that
* interface. It forbids traffic between guests on the same bridge
* represented by that interface.
*
* Returns 0 in case of success or an error code otherwise
*/
void
iptablesRemoveForwardAllowCross(virFirewallPtr fw,
virFirewallLayer layer,
const char *iface)
{
virFirewallAddRule(fw, layer,
"--table", "filter",
"--delete", "FORWARD",
"--in-interface", iface,
"--out-interface", iface,
"--jump", "ACCEPT",
NULL);
}
/**
* iptablesAddForwardRejectOut:
* @ctx: pointer to the IP table context
* @iface: the output interface name
*
* Add rules to the IP table context to forbid all traffic to that
* interface. It forbids forwarding from the bridge to that interface.
*
* Returns 0 in case of success or an error code otherwise
*/
void
iptablesAddForwardRejectOut(virFirewallPtr fw,
virFirewallLayer layer,
const char *iface)
{
virFirewallAddRule(fw, layer,
"--table", "filter",
"--insert", "FORWARD",
"--in-interface", iface,
"--jump", "REJECT",
NULL);
}
/**
* iptablesRemoveForwardRejectOut:
* @ctx: pointer to the IP table context
* @iface: the output interface name
*
* Remove rules from the IP table context forbidding all traffic to that
* interface. It reallow forwarding from the bridge to that interface.
*
* Returns 0 in case of success or an error code otherwise
*/
void
iptablesRemoveForwardRejectOut(virFirewallPtr fw,
virFirewallLayer layer,
const char *iface)
{
virFirewallAddRule(fw, layer,
"--table", "filter",
"--delete", "FORWARD",
"--in-interface", iface,
"--jump", "REJECT",
NULL);
}
/**
* iptablesAddForwardRejectIn:
* @ctx: pointer to the IP table context
* @iface: the input interface name
*
* Add rules to the IP table context to forbid all traffic from that
* interface. It forbids forwarding from that interface to the bridge.
*
* Returns 0 in case of success or an error code otherwise
*/
void
iptablesAddForwardRejectIn(virFirewallPtr fw,
virFirewallLayer layer,
const char *iface)
{
virFirewallAddRule(fw, layer,
"--table", "filter",
"--insert", "FORWARD",
"--out-interface", iface,
"--jump", "REJECT",
NULL);
}
/**
* iptablesRemoveForwardRejectIn:
* @ctx: pointer to the IP table context
* @iface: the input interface name
*
* Remove rules from the IP table context forbidding all traffic from that
* interface. It allows forwarding from that interface to the bridge.
*
* Returns 0 in case of success or an error code otherwise
*/
void
iptablesRemoveForwardRejectIn(virFirewallPtr fw,
virFirewallLayer layer,
const char *iface)
{
virFirewallAddRule(fw, layer,
"--table", "filter",
"--delete", "FORWARD",
"--out-interface", iface,
"--jump", "REJECT",
NULL);
}
/* Masquerade all traffic coming from the network associated
* with the bridge
*/
static int
iptablesForwardMasquerade(virFirewallPtr fw,
virSocketAddr *netaddr,
unsigned int prefix,
const char *physdev,
virSocketAddrRangePtr addr,
virPortRangePtr port,
const char *protocol,
int action)
{
VIR_AUTOFREE(char *) networkstr = NULL;
VIR_AUTOFREE(char *) addrStartStr = NULL;
VIR_AUTOFREE(char *) addrEndStr = NULL;
VIR_AUTOFREE(char *) portRangeStr = NULL;
VIR_AUTOFREE(char *) natRangeStr = NULL;
virFirewallRulePtr rule;
if (!(networkstr = iptablesFormatNetwork(netaddr, prefix)))
return -1;
if (!VIR_SOCKET_ADDR_IS_FAMILY(netaddr, AF_INET)) {
/* Higher level code *should* guaranteee it's impossible to get here. */
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Attempted to NAT '%s'. NAT is only supported for IPv4."),
networkstr);
return -1;
}
if (VIR_SOCKET_ADDR_IS_FAMILY(&addr->start, AF_INET)) {
if (!(addrStartStr = virSocketAddrFormat(&addr->start)))
return -1;
if (VIR_SOCKET_ADDR_IS_FAMILY(&addr->end, AF_INET)) {
if (!(addrEndStr = virSocketAddrFormat(&addr->end)))
return -1;
}
}
if (protocol && protocol[0]) {
rule = virFirewallAddRule(fw, VIR_FIREWALL_LAYER_IPV4,
"--table", "nat",
action == ADD ? "--insert" : "--delete", "POSTROUTING",
"--source", networkstr,
"-p", protocol,
"!", "--destination", networkstr,
NULL);
} else {
rule = virFirewallAddRule(fw, VIR_FIREWALL_LAYER_IPV4,
"--table", "nat",
action == ADD ? "--insert" : "--delete", "POSTROUTING",
"--source", networkstr,
"!", "--destination", networkstr,
NULL);
}
if (physdev && physdev[0])
virFirewallRuleAddArgList(fw, rule, "--out-interface", physdev, NULL);
if (protocol && protocol[0]) {
if (port->start == 0 && port->end == 0) {
port->start = 1024;
port->end = 65535;
}
if (port->start < port->end && port->end < 65536) {
if (virAsprintf(&portRangeStr, ":%u-%u",
port->start, port->end) < 0)
return -1;
} else {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Invalid port range '%u-%u'."),
port->start, port->end);
}
}
/* Use --jump SNAT if public addr is specified */
if (addrStartStr && addrStartStr[0]) {
int r = 0;
if (addrEndStr && addrEndStr[0]) {
r = virAsprintf(&natRangeStr, "%s-%s%s", addrStartStr, addrEndStr,
portRangeStr ? portRangeStr : "");
} else {
r = virAsprintf(&natRangeStr, "%s%s", addrStartStr,
portRangeStr ? portRangeStr : "");
}
if (r < 0)
return -1;
virFirewallRuleAddArgList(fw, rule,
"--jump", "SNAT",
"--to-source", natRangeStr, NULL);
} else {
virFirewallRuleAddArgList(fw, rule,
"--jump", "MASQUERADE", NULL);
if (portRangeStr && portRangeStr[0])
virFirewallRuleAddArgList(fw, rule,
"--to-ports", &portRangeStr[1], NULL);
}
return 0;
}
/**
* iptablesAddForwardMasquerade:
* @ctx: pointer to the IP table context
* @network: the source network name
* @physdev: the physical input device or NULL
* @protocol: the network protocol or NULL
*
* Add rules to the IP table context to allow masquerading
* network @network on @physdev. This allow the bridge to
* masquerade for that network (on @physdev).
*
* Returns 0 in case of success or an error code otherwise
*/
int
iptablesAddForwardMasquerade(virFirewallPtr fw,
virSocketAddr *netaddr,
unsigned int prefix,
const char *physdev,
virSocketAddrRangePtr addr,
virPortRangePtr port,
const char *protocol)
{
return iptablesForwardMasquerade(fw, netaddr, prefix, physdev, addr, port,
protocol, ADD);
}
/**
* iptablesRemoveForwardMasquerade:
* @ctx: pointer to the IP table context
* @network: the source network name
* @physdev: the physical input device or NULL
* @protocol: the network protocol or NULL
*
* Remove rules from the IP table context to stop masquerading
* network @network on @physdev. This stops the bridge from
* masquerading for that network (on @physdev).
*
* Returns 0 in case of success or an error code otherwise
*/
int
iptablesRemoveForwardMasquerade(virFirewallPtr fw,
virSocketAddr *netaddr,
unsigned int prefix,
const char *physdev,
virSocketAddrRangePtr addr,
virPortRangePtr port,
const char *protocol)
{
return iptablesForwardMasquerade(fw, netaddr, prefix, physdev, addr, port,
protocol, REMOVE);
}
/* Don't masquerade traffic coming from the network associated with the bridge
* if said traffic targets @destaddr.
*/
static int
iptablesForwardDontMasquerade(virFirewallPtr fw,
virSocketAddr *netaddr,
unsigned int prefix,
const char *physdev,
const char *destaddr,
int action)
{
VIR_AUTOFREE(char *) networkstr = NULL;
if (!(networkstr = iptablesFormatNetwork(netaddr, prefix)))
return -1;
if (!VIR_SOCKET_ADDR_IS_FAMILY(netaddr, AF_INET)) {
/* Higher level code *should* guaranteee it's impossible to get here. */
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Attempted to NAT '%s'. NAT is only supported for IPv4."),
networkstr);
return -1;
}
if (physdev && physdev[0])
virFirewallAddRule(fw, VIR_FIREWALL_LAYER_IPV4,
"--table", "nat",
action == ADD ? "--insert" : "--delete", "POSTROUTING",
"--out-interface", physdev,
"--source", networkstr,
"--destination", destaddr,
"--jump", "RETURN",
NULL);
else
virFirewallAddRule(fw, VIR_FIREWALL_LAYER_IPV4,
"--table", "nat",
action == ADD ? "--insert" : "--delete", "POSTROUTING",
"--source", networkstr,
"--destination", destaddr,
"--jump", "RETURN",
NULL);
return 0;
}
/**
* iptablesAddDontMasquerade:
* @netaddr: the source network name
* @prefix: prefix (# of 1 bits) of netmask to apply to @netaddr
* @physdev: the physical output device or NULL
* @destaddr: the destination network not to masquerade for
*
* Add rules to the IP table context to avoid masquerading from
* @netaddr/@prefix to @destaddr on @physdev. @destaddr must be in a format
* directly consumable by iptables, it must not depend on user input or
* configuration.
*
* Returns 0 in case of success or an error code otherwise.
*/
int
iptablesAddDontMasquerade(virFirewallPtr fw,
virSocketAddr *netaddr,
unsigned int prefix,
const char *physdev,
const char *destaddr)
{
return iptablesForwardDontMasquerade(fw, netaddr, prefix, physdev, destaddr,
ADD);
}
/**
* iptablesRemoveDontMasquerade:
* @netaddr: the source network name
* @prefix: prefix (# of 1 bits) of netmask to apply to @netaddr
* @physdev: the physical output device or NULL
* @destaddr: the destination network not to masquerade for
*
* Remove rules from the IP table context that prevent masquerading from
* @netaddr/@prefix to @destaddr on @physdev. @destaddr must be in a format
* directly consumable by iptables, it must not depend on user input or
* configuration.
*
* Returns 0 in case of success or an error code otherwise.
*/
int
iptablesRemoveDontMasquerade(virFirewallPtr fw,
virSocketAddr *netaddr,
unsigned int prefix,
const char *physdev,
const char *destaddr)
{
return iptablesForwardDontMasquerade(fw, netaddr, prefix, physdev, destaddr,
REMOVE);
}
static void
iptablesOutputFixUdpChecksum(virFirewallPtr fw,
const char *iface,
int port,
int action)
{
char portstr[32];
snprintf(portstr, sizeof(portstr), "%d", port);
portstr[sizeof(portstr) - 1] = '\0';
virFirewallAddRule(fw, VIR_FIREWALL_LAYER_IPV4,
"--table", "mangle",
action == ADD ? "--insert" : "--delete", "POSTROUTING",
"--out-interface", iface,
"--protocol", "udp",
"--destination-port", portstr,
"--jump", "CHECKSUM", "--checksum-fill",
NULL);
}
/**
* iptablesAddOutputFixUdpChecksum:
* @ctx: pointer to the IP table context
* @iface: the interface name
* @port: the UDP port to match
*
* Add a rule to the mangle table's POSTROUTING chain that fixes up the
* checksum of packets with the given destination @port.
* the given @iface interface for TCP packets.
*
*/
void
iptablesAddOutputFixUdpChecksum(virFirewallPtr fw,
const char *iface,
int port)
{
iptablesOutputFixUdpChecksum(fw, iface, port, ADD);
}
/**
* iptablesRemoveOutputFixUdpChecksum:
* @ctx: pointer to the IP table context
* @iface: the interface name
* @port: the UDP port of the rule to remove
*
* Removes the checksum fixup rule that was previous added with
* iptablesAddOutputFixUdpChecksum.
*/
void
iptablesRemoveOutputFixUdpChecksum(virFirewallPtr fw,
const char *iface,
int port)
{
iptablesOutputFixUdpChecksum(fw, iface, port, REMOVE);
}