On Sun, Feb 26, 2017 at 3:49 PM, Richard Guy Briggs <rgb(a)redhat.com> wrote:
Eliminate flipping in and out of message fields, dropping fields in
the process.
Sample raw message format IPv4 UDP:
type=NETFILTER_PKT msg=audit(1487874761.386:228): mark=0xae8a2732 saddr=127.0.0.1
daddr=127.0.0.1 proto=17^]
Sample raw message format IPv6 ICMP6:
type=NETFILTER_PKT msg=audit(1487874761.381:227): mark=0x223894b7 saddr=::1 daddr=::1
proto=58^]
Issue:
https://github.com/linux-audit/audit-kernel/issues/11
Test case:
https://github.com/linux-audit/audit-testsuite/issues/43
Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com>
---
net/netfilter/xt_AUDIT.c | 122 ++++++++++-----------------------------------
1 files changed, 27 insertions(+), 95 deletions(-)
diff --git a/net/netfilter/xt_AUDIT.c b/net/netfilter/xt_AUDIT.c
index 4973cbd..945fa29 100644
--- a/net/netfilter/xt_AUDIT.c
+++ b/net/netfilter/xt_AUDIT.c
@@ -31,146 +31,78 @@ MODULE_ALIAS("ip6t_AUDIT");
...
-static void audit_ip4(struct audit_buffer *ab, struct sk_buff *skb)
+static bool audit_ip4(struct audit_buffer *ab, struct sk_buff *skb)
{
struct iphdr _iph;
const struct iphdr *ih;
ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph);
It seems like we should be using skb_network_offset(skb) instead of 0
above, yes? Granted, this isn't new, but let's fix it.
- if (!ih) {
- audit_log_format(ab, " truncated=1");
- return;
- }
+ if (!ih)
+ return false;
- audit_log_format(ab, " saddr=%pI4 daddr=%pI4 ipid=%hu proto=%hhu",
- &ih->saddr, &ih->daddr, ntohs(ih->id),
ih->protocol);
+ audit_log_format(ab, " saddr=%pI4 daddr=%pI4 proto=%hhu",
+ &ih->saddr, &ih->daddr, ih->protocol);
- if (ntohs(ih->frag_off) & IP_OFFSET) {
- audit_log_format(ab, " frag=1");
- return;
- }
-
- audit_proto(ab, skb, ih->protocol, ih->ihl * 4);
+ return true;
}
...
static unsigned int
audit_tg(struct sk_buff *skb, const struct xt_action_param *par)
{
- const struct xt_audit_info *info = par->targinfo;
struct audit_buffer *ab;
+ int fam = -1;
if (audit_enabled == 0)
goto errout;
-
ab = audit_log_start(NULL, GFP_ATOMIC, AUDIT_NETFILTER_PKT);
if (ab == NULL)
goto errout;
- audit_log_format(ab, "action=%hhu hook=%u len=%u inif=%s outif=%s",
- info->type, par->hooknum, skb->len,
- par->in ? par->in->name : "?",
- par->out ? par->out->name : "?");
-
- if (skb->mark)
- audit_log_format(ab, " mark=%#x", skb->mark);
-
- if (skb->dev && skb->dev->type == ARPHRD_ETHER) {
- audit_log_format(ab, " smac=%pM dmac=%pM macproto=0x%04x",
- eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest,
- ntohs(eth_hdr(skb)->h_proto));
+ audit_log_format(ab, "mark=%#x", skb->mark ?: -1);
How do Steve's userspace tools like the unset/-1 value represented
when it is a hex value: -1 or 0xffffffff?
--
paul moore
www.paul-moore.com