External/libvirt
1
0
Fork 0
mirror of https://gitlab.com/libvirt/libvirt.git synced 2025-02-24 20:32:22 +00:00
Code Issues Packages Projects Releases Wiki Activity

nwfiler: fix due to non-symmetric src mac address match in iptables

Browse Source 
The attached patch fixes a problem due to the mac match in iptables only
supporting --mac-source and no --mac-destination, thus it not being
symmetric. Therefore a rule like this one

<rule action='drop' direction='out'>
  <all match='no' srcmacaddr='$MAC'/>
</rule>

should only have the MAC match on traffic leaving the VM and not test
for the same source MAC address on traffic that the VM receives.
This commit is contained in:
Stefan Berger 2010-04-07 06:28:16 -04:00
parent d33b87268d
commit f8352e221f
1 changed files with 51 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

61
src/nwfilter/nwfilter_ebiptables_driver.c
View File

@ -772,11 +772,18 @@ static int
iptablesHandleSrcMacAddr(virBufferPtr buf,
virNWFilterHashTablePtr vars,
nwItemDescPtr srcMacAddr,
int directionIn ATTRIBUTE_UNUSED)
int directionIn,
bool *srcmacskipped)
{
char macaddr[VIR_MAC_STRING_BUFLEN];
*srcmacskipped = false;
if (HAS_ENTRY_ITEM(srcMacAddr)) {
if (directionIn) {
*srcmacskipped = true;
return 0;
}
if (printDataType(vars,
macaddr, sizeof(macaddr),
srcMacAddr))
@ -1039,6 +1046,8 @@ _iptablesCreateRuleInstance(int directionIn,
virBuffer buf = VIR_BUFFER_INITIALIZER;
const char *target;
const char *iptables_cmd = (isIPv6) ? IP6TABLES_CMD : IPTABLES_CMD;
unsigned int bufUsed;
bool srcMacSkipped = false;
PRINT_IPT_ROOT_CHAIN(chain, chainPrefix, ifname);
@ -1052,10 +1061,13 @@ _iptablesCreateRuleInstance(int directionIn,
virBufferAddLit(&buf, " -p tcp");
bufUsed = virBufferUse(&buf);
if (iptablesHandleSrcMacAddr(&buf,
vars,
&rule->p.tcpHdrFilter.dataSrcMACAddr,
directionIn))
directionIn,
&srcMacSkipped))
goto err_exit;
if (iptablesHandleIpHdr(&buf,
@ -1093,10 +1105,13 @@ _iptablesCreateRuleInstance(int directionIn,
virBufferAddLit(&buf, " -p udp");
bufUsed = virBufferUse(&buf);
if (iptablesHandleSrcMacAddr(&buf,
vars,
&rule->p.udpHdrFilter.dataSrcMACAddr,
directionIn))
directionIn,
&srcMacSkipped))
goto err_exit;
if (iptablesHandleIpHdr(&buf,
@ -1121,10 +1136,13 @@ _iptablesCreateRuleInstance(int directionIn,
virBufferAddLit(&buf, " -p udplite");
bufUsed = virBufferUse(&buf);
if (iptablesHandleSrcMacAddr(&buf,
vars,
&rule->p.udpliteHdrFilter.dataSrcMACAddr,
directionIn))
directionIn,
&srcMacSkipped))
goto err_exit;
if (iptablesHandleIpHdr(&buf,
@ -1144,10 +1162,13 @@ _iptablesCreateRuleInstance(int directionIn,
virBufferAddLit(&buf, " -p esp");
bufUsed = virBufferUse(&buf);
if (iptablesHandleSrcMacAddr(&buf,
vars,
&rule->p.espHdrFilter.dataSrcMACAddr,
directionIn))
directionIn,
&srcMacSkipped))
goto err_exit;
if (iptablesHandleIpHdr(&buf,
@ -1167,10 +1188,13 @@ _iptablesCreateRuleInstance(int directionIn,
virBufferAddLit(&buf, " -p ah");
bufUsed = virBufferUse(&buf);
if (iptablesHandleSrcMacAddr(&buf,
vars,
&rule->p.ahHdrFilter.dataSrcMACAddr,
directionIn))
directionIn,
&srcMacSkipped))
goto err_exit;
if (iptablesHandleIpHdr(&buf,
@ -1190,10 +1214,13 @@ _iptablesCreateRuleInstance(int directionIn,
virBufferAddLit(&buf, " -p sctp");
bufUsed = virBufferUse(&buf);
if (iptablesHandleSrcMacAddr(&buf,
vars,
&rule->p.sctpHdrFilter.dataSrcMACAddr,
directionIn))
directionIn,
&srcMacSkipped))
goto err_exit;
if (iptablesHandleIpHdr(&buf,
@ -1221,10 +1248,13 @@ _iptablesCreateRuleInstance(int directionIn,
else
virBufferAddLit(&buf, " -p icmpv6");
bufUsed = virBufferUse(&buf);
if (iptablesHandleSrcMacAddr(&buf,
vars,
&rule->p.icmpHdrFilter.dataSrcMACAddr,
directionIn))
directionIn,
&srcMacSkipped))
goto err_exit;
if (iptablesHandleIpHdr(&buf,
@ -1272,10 +1302,13 @@ _iptablesCreateRuleInstance(int directionIn,
virBufferAddLit(&buf, " -p igmp");
bufUsed = virBufferUse(&buf);
if (iptablesHandleSrcMacAddr(&buf,
vars,
&rule->p.igmpHdrFilter.dataSrcMACAddr,
directionIn))
directionIn,
&srcMacSkipped))
goto err_exit;
if (iptablesHandleIpHdr(&buf,
@ -1295,10 +1328,13 @@ _iptablesCreateRuleInstance(int directionIn,
virBufferAddLit(&buf, " -p all");
bufUsed = virBufferUse(&buf);
if (iptablesHandleSrcMacAddr(&buf,
vars,
&rule->p.allHdrFilter.dataSrcMACAddr,
directionIn))
directionIn,
&srcMacSkipped))
goto err_exit;
if (iptablesHandleIpHdr(&buf,
@ -1313,6 +1349,11 @@ _iptablesCreateRuleInstance(int directionIn,
return -1;
}
if (srcMacSkipped && bufUsed == virBufferUse(&buf)) {
virBufferFreeAndReset(&buf);
return 0;
}
if (match)
virBufferVSprintf(&buf, " %s", match);