From f19590b07cb620be1fcd5474c49515e21a05d406 Mon Sep 17 00:00:00 2001 From: Ricardo Robaina Date: Fri, 14 Nov 2025 09:36:16 -0300 Subject: audit: add audit_log_nf_skb helper function Netfilter code (net/netfilter/nft_log.c and net/netfilter/xt_AUDIT.c) have to be kept in sync. Both source files had duplicated versions of audit_ip4() and audit_ip6() functions, which can result in lack of consistency and/or duplicated work. This patch adds a helper function in audit.c that can be called by netfilter code commonly, aiming to improve maintainability and consistency. Suggested-by: Florian Westphal Suggested-by: Paul Moore Signed-off-by: Ricardo Robaina Acked-by: Florian Westphal Signed-off-by: Paul Moore --- kernel/audit.c | 64 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 64 insertions(+) (limited to 'kernel') diff --git a/kernel/audit.c b/kernel/audit.c index 26a332ffb1b8..5c302c4592db 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -58,6 +58,8 @@ #include #include #include +#include +#include #include "audit.h" @@ -2488,6 +2490,68 @@ void audit_log_path_denied(int type, const char *operation) audit_log_end(ab); } +int audit_log_nf_skb(struct audit_buffer *ab, + const struct sk_buff *skb, u8 nfproto) +{ + /* find the IP protocol in the case of NFPROTO_BRIDGE */ + if (nfproto == NFPROTO_BRIDGE) { + switch (eth_hdr(skb)->h_proto) { + case htons(ETH_P_IP): + nfproto = NFPROTO_IPV4; + break; + case htons(ETH_P_IPV6): + nfproto = NFPROTO_IPV6; + break; + default: + goto unknown_proto; + } + } + + switch (nfproto) { + case NFPROTO_IPV4: { + struct iphdr iph; + const struct iphdr *ih; + + ih = skb_header_pointer(skb, skb_network_offset(skb), + sizeof(iph), &iph); + if (!ih) + return -ENOMEM; + + audit_log_format(ab, " saddr=%pI4 daddr=%pI4 proto=%hhu", + &ih->saddr, &ih->daddr, ih->protocol); + break; + } + case NFPROTO_IPV6: { + struct ipv6hdr iph; + const struct ipv6hdr *ih; + u8 nexthdr; + __be16 frag_off; + + ih = skb_header_pointer(skb, skb_network_offset(skb), + sizeof(iph), &iph); + if (!ih) + return -ENOMEM; + + nexthdr = ih->nexthdr; + ipv6_skip_exthdr(skb, skb_network_offset(skb) + sizeof(iph), + &nexthdr, &frag_off); + + audit_log_format(ab, " saddr=%pI6c daddr=%pI6c proto=%hhu", + &ih->saddr, &ih->daddr, nexthdr); + break; + } + default: + goto unknown_proto; + } + + return 0; + +unknown_proto: + audit_log_format(ab, " saddr=? daddr=? proto=?"); + return -EPFNOSUPPORT; +} +EXPORT_SYMBOL(audit_log_nf_skb); + /* global counter which is incremented every time something logs in */ static atomic_t session_id = ATOMIC_INIT(0); -- cgit v1.2.3 From 15b0c43aa621fb77b32c46eb642eaf25557e9fdb Mon Sep 17 00:00:00 2001 From: Ricardo Robaina Date: Fri, 14 Nov 2025 09:36:17 -0300 Subject: audit: include source and destination ports to NETFILTER_PKT NETFILTER_PKT records show both source and destination addresses, in addition to the associated networking protocol. However, it lacks the ports information, which is often valuable for troubleshooting. This patch adds both source and destination port numbers, 'sport' and 'dport' respectively, to TCP, UDP, UDP-Lite and SCTP-related NETFILTER_PKT records. $ TESTS="netfilter_pkt" make -e test &> /dev/null $ ausearch -i -ts recent |grep NETFILTER_PKT type=NETFILTER_PKT ... proto=icmp type=NETFILTER_PKT ... proto=ipv6-icmp type=NETFILTER_PKT ... proto=udp sport=46333 dport=42424 type=NETFILTER_PKT ... proto=udp sport=35953 dport=42424 type=NETFILTER_PKT ... proto=tcp sport=50314 dport=42424 type=NETFILTER_PKT ... proto=tcp sport=57346 dport=42424 Link: https://github.com/linux-audit/audit-kernel/issues/162 Signed-off-by: Ricardo Robaina Acked-by: Florian Westphal Signed-off-by: Paul Moore --- kernel/audit.c | 103 ++++++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 99 insertions(+), 4 deletions(-) (limited to 'kernel') diff --git a/kernel/audit.c b/kernel/audit.c index 5c302c4592db..39c4f26c484d 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -60,6 +60,7 @@ #include #include #include +#include #include "audit.h" @@ -2517,8 +2518,55 @@ int audit_log_nf_skb(struct audit_buffer *ab, if (!ih) return -ENOMEM; - audit_log_format(ab, " saddr=%pI4 daddr=%pI4 proto=%hhu", - &ih->saddr, &ih->daddr, ih->protocol); + switch (ih->protocol) { + case IPPROTO_TCP: { + struct tcphdr _tcph; + const struct tcphdr *th; + + th = skb_header_pointer(skb, skb_transport_offset(skb), + sizeof(_tcph), &_tcph); + if (!th) + return -ENOMEM; + + audit_log_format(ab, " saddr=%pI4 daddr=%pI4 proto=%hhu sport=%hu dport=%hu", + &ih->saddr, &ih->daddr, ih->protocol, + ntohs(th->source), ntohs(th->dest)); + break; + } + case IPPROTO_UDP: + case IPPROTO_UDPLITE: { + struct udphdr _udph; + const struct udphdr *uh; + + uh = skb_header_pointer(skb, skb_transport_offset(skb), + sizeof(_udph), &_udph); + if (!uh) + return -ENOMEM; + + audit_log_format(ab, " saddr=%pI4 daddr=%pI4 proto=%hhu sport=%hu dport=%hu", + &ih->saddr, &ih->daddr, ih->protocol, + ntohs(uh->source), ntohs(uh->dest)); + break; + } + case IPPROTO_SCTP: { + struct sctphdr _sctph; + const struct sctphdr *sh; + + sh = skb_header_pointer(skb, skb_transport_offset(skb), + sizeof(_sctph), &_sctph); + if (!sh) + return -ENOMEM; + + audit_log_format(ab, " saddr=%pI4 daddr=%pI4 proto=%hhu sport=%hu dport=%hu", + &ih->saddr, &ih->daddr, ih->protocol, + ntohs(sh->source), ntohs(sh->dest)); + break; + } + default: + audit_log_format(ab, " saddr=%pI4 daddr=%pI4 proto=%hhu", + &ih->saddr, &ih->daddr, ih->protocol); + } + break; } case NFPROTO_IPV6: { @@ -2536,8 +2584,55 @@ int audit_log_nf_skb(struct audit_buffer *ab, ipv6_skip_exthdr(skb, skb_network_offset(skb) + sizeof(iph), &nexthdr, &frag_off); - audit_log_format(ab, " saddr=%pI6c daddr=%pI6c proto=%hhu", - &ih->saddr, &ih->daddr, nexthdr); + switch (nexthdr) { + case IPPROTO_TCP: { + struct tcphdr _tcph; + const struct tcphdr *th; + + th = skb_header_pointer(skb, skb_transport_offset(skb), + sizeof(_tcph), &_tcph); + if (!th) + return -ENOMEM; + + audit_log_format(ab, " saddr=%pI6c daddr=%pI6c proto=%hhu sport=%hu dport=%hu", + &ih->saddr, &ih->daddr, nexthdr, + ntohs(th->source), ntohs(th->dest)); + break; + } + case IPPROTO_UDP: + case IPPROTO_UDPLITE: { + struct udphdr _udph; + const struct udphdr *uh; + + uh = skb_header_pointer(skb, skb_transport_offset(skb), + sizeof(_udph), &_udph); + if (!uh) + return -ENOMEM; + + audit_log_format(ab, " saddr=%pI6c daddr=%pI6c proto=%hhu sport=%hu dport=%hu", + &ih->saddr, &ih->daddr, nexthdr, + ntohs(uh->source), ntohs(uh->dest)); + break; + } + case IPPROTO_SCTP: { + struct sctphdr _sctph; + const struct sctphdr *sh; + + sh = skb_header_pointer(skb, skb_transport_offset(skb), + sizeof(_sctph), &_sctph); + if (!sh) + return -ENOMEM; + + audit_log_format(ab, " saddr=%pI6c daddr=%pI6c proto=%hhu sport=%hu dport=%hu", + &ih->saddr, &ih->daddr, nexthdr, + ntohs(sh->source), ntohs(sh->dest)); + break; + } + default: + audit_log_format(ab, " saddr=%pI6c daddr=%pI6c proto=%hhu", + &ih->saddr, &ih->daddr, nexthdr); + } + break; } default: -- cgit v1.2.3