Re: [libvirt] [PATCH] nwfilter: Add support for icmpv6 filtering

Make use of the ebtables functionality to be able to filter certain parameters of icmpv6 packets. Extend the XML parser for icmpv6 types, type ranges, codes, and code ranges. Extend the nwfilter documentation, schema, and test cases. Being able to filter icmpv6 types and codes helps extending the DHCP snooper for IPv6 and filtering at least some parameters of IPv6's NDP (Neighbor Discovery Protocol) packets. However, the filtering will not be as good as the filtering of ARP packets since we cannot check on IP addresses in the payload of the NDP packets. Signed-off-by: Stefan Berger stefanb(a)linux.vnet.ibm.com --- docs/formatnwfilter.html.in | 20 +++++++ docs/schemas/nwfilter.rng | 26 +++++++++ src/conf/nwfilter_conf.c | 26 +++++++++ src/conf/nwfilter_conf.h | 4 ++ src/nwfilter/nwfilter_ebiptables_driver.c | 80 ++++++++++++++++++++++++++ tests/nwfilterxml2firewalldata/ipv6-linux.args | 16 ++++++ tests/nwfilterxml2firewalldata/ipv6.xml | 38 ++++++++++++ tests/nwfilterxml2xmlin/ipv6-test.xml | 38 ++++++++++++ tests/nwfilterxml2xmlout/ipv6-test.xml | 12 ++++ 9 files changed, 260 insertions(+) diff --git a/docs/formatnwfilter.html.in b/docs/formatnwfilter.html.in index 073b852..7c0dd5b 100644

diff --git a/src/conf/nwfilter_conf.c b/src/conf/nwfilter_conf.c index 074d745..0108dbe 100644 --- a/src/conf/nwfilter_conf.c +++ b/src/conf/nwfilter_conf.c @@ -1445,6 +1445,26 @@ static const virXMLAttr2Struct ipv6Attributes[] = { .datatype = DATATYPE_UINT16 | DATATYPE_UINT16_HEX, .dataIdx = offsetof(virNWFilterRuleDef, p.ipv6HdrFilter.portData.dataDstPortEnd), }, + { + .name = "type", + .datatype = DATATYPE_UINT8 | DATATYPE_UINT8_HEX, + .dataIdx = offsetof(virNWFilterRuleDef, p.ipv6HdrFilter.dataICMPTypeStart), + }, + { + .name = "typeend", + .datatype = DATATYPE_UINT8 | DATATYPE_UINT8_HEX, + .dataIdx = offsetof(virNWFilterRuleDef, p.ipv6HdrFilter.dataICMPTypeEnd), + }, + { + .name = "code", + .datatype = DATATYPE_UINT8 | DATATYPE_UINT8_HEX, + .dataIdx = offsetof(virNWFilterRuleDef, p.ipv6HdrFilter.dataICMPCodeStart), + }, + { + .name = "codeend", + .datatype = DATATYPE_UINT8 | DATATYPE_UINT8_HEX, + .dataIdx = offsetof(virNWFilterRuleDef, p.ipv6HdrFilter.dataICMPCodeEnd), + }, COMMENT_PROP_IPHDR(ipv6HdrFilter), { .name = NULL, @@ -2219,6 +2239,12 @@ virNWFilterRuleDefFixup(virNWFilterRuleDefPtr rule) rule->p.ipv6HdrFilter.ipHdr.dataSrcIPAddr); COPY_NEG_SIGN(rule->p.ipv6HdrFilter.ipHdr.dataDstIPMask, rule->p.ipv6HdrFilter.ipHdr.dataDstIPAddr); + COPY_NEG_SIGN(rule->p.icmpHdrFilter.dataICMPTypeend, + rule->p.icmpHdrFilter.dataICMPType); + COPY_NEG_SIGN(rule->p.icmpHdrFilter.dataICMPCode, + rule->p.icmpHdrFilter.dataICMPType); + COPY_NEG_SIGN(rule->p.icmpHdrFilter.dataICMPCodeend, + rule->p.icmpHdrFilter.dataICMPType);

virNWFilterRuleDefFixupIPSet(&rule->p.ipv6HdrFilter.ipHdr); break; diff --git a/src/conf/nwfilter_conf.h b/src/conf/nwfilter_conf.h index f81df60..6e68ecc 100644 --- a/src/conf/nwfilter_conf.h +++ b/src/conf/nwfilter_conf.h @@ -265,6 +265,10 @@ struct _ipv6HdrFilterDef { ethHdrDataDef ethHdr; ipHdrDataDef ipHdr; portDataDef portData; + nwItemDesc dataICMPTypeStart; + nwItemDesc dataICMPTypeEnd; + nwItemDesc dataICMPCodeStart; + nwItemDesc dataICMPCodeEnd; }; diff --git a/src/nwfilter/nwfilter_ebiptables_driver.c b/src/nwfilter/nwfilter_ebiptables_driver.c index 377b59b..d7a94ee 100644 --- a/src/nwfilter/nwfilter_ebiptables_driver.c +++ b/src/nwfilter/nwfilter_ebiptables_driver.c @@ -1826,6 +1826,7 @@ ebtablesCreateRuleInstance(virFirewallPtr fw, bool hasMask = false; virFirewallRulePtr fwrule; int ret = -1; + virBuffer buf = VIR_BUFFER_INITIALIZER; if (STREQ(chainSuffix, virNWFilterChainSuffixTypeToString( @@ -2342,6 +2343,83 @@ ebtablesCreateRuleInstance(virFirewallPtr fw, virFirewallRuleAddArg(fw, fwrule, number); } } + + if (HAS_ENTRY_ITEM(&rule->p.ipv6HdrFilter.dataICMPTypeStart) || + HAS_ENTRY_ITEM(&rule->p.ipv6HdrFilter.dataICMPTypeEnd) || + HAS_ENTRY_ITEM(&rule->p.ipv6HdrFilter.dataICMPCodeStart) || + HAS_ENTRY_ITEM(&rule->p.ipv6HdrFilter.dataICMPCodeEnd) ) { + bool lo = false; + char *r; + + virFirewallRuleAddArg(fw, fwrule, + "--ip6-icmp-type"); + + if (HAS_ENTRY_ITEM(&rule->p.ipv6HdrFilter.dataICMPTypeStart)) { + if (printDataType(vars, + number, sizeof(number), + &rule->p.ipv6HdrFilter.dataICMPTypeStart) < 0) + goto cleanup; + lo = true; + } else { + ignore_value(virStrcpyStatic(number, "0")); + } + + virBufferStrcat(&buf, number, ":", NULL); + + if HAS_ENTRY_ITEM(&rule->p.ipv6HdrFilter.dataICMPTypeEnd) {