[RFC PATCH] audit: normalize NETFILTER_PKT
Richard Guy Briggs
rgb at redhat.com
Tue Jan 31 12:57:23 UTC 2017
On 2017-01-30 10:13, Richard Guy Briggs wrote:
> On 2017-01-30 15:53, Steve Grubb wrote:
> > On Fri, 27 Jan 2017 08:11:06 -0500
> > Richard Guy Briggs <rgb at redhat.com> wrote:
> > > Eliminate flipping in and out of message fields.
> > >
> > > https://github.com/linux-audit/audit-kernel/issues/11
> >
> > Do you have sample events that shows how this changes the record
> > format? I like to review how the event looks when a patch changes or
> > adds a record.
>
> I used the format that was proposed. Here are several samples from
> running this RFC patch through the RFC test script:
>
> ausearch --start 01/27/2017 -i -m netfilter_pkt
> ----
> type=NETFILTER_PKT msg=audit(01/27/2017 08:03:35.649:183) : action=ACCEPT hook=OUTPUT len=84 inif=? outif=lo mark=0xa044a1d4 smac=? dmac=? macproto=UNKNOWN trunc=-1 saddr=127.0.0.1 daddr=127.0.0.1 ipid=26581 proto=icmp frag=255 trunc=-1 sport=65535 dport=65535 icmptype=echo icmpcode=0
> ----
> type=NETFILTER_PKT msg=audit(01/27/2017 08:03:35.649:184) : action=ACCEPT hook=INPUT len=84 inif=lo outif=? mark=0xbadeac28 smac=? dmac=? macproto=UNKNOWN trunc=-1 saddr=127.0.0.1 daddr=127.0.0.1 ipid=26581 proto=icmp frag=255 trunc=-1 sport=65535 dport=65535 icmptype=echo icmpcode=0
> ----
> type=NETFILTER_PKT msg=audit(01/27/2017 08:03:35.652:185) : action=ACCEPT hook=INPUT len=104 inif=lo outif=? mark=0xb404724 smac=? dmac=? macproto=UNKNOWN trunc=-1 saddr=::1 daddr=::1 ipid=-1 proto=ipv6-icmp frag=-1 trunc=-1 sport=65535 dport=65535 icmptype=unknown icmp type (128) icmpcode=0
> ----
> type=NETFILTER_PKT msg=audit(01/27/2017 08:03:35.655:186) : action=ACCEPT hook=INPUT len=60 inif=lo outif=? mark=0xe2bd8098 smac=? dmac=? macproto=UNKNOWN trunc=-1 saddr=127.0.0.1 daddr=127.0.0.1 ipid=29381 proto=tcp frag=255 trunc=-1 sport=51064 dport=42424 icmptype=unknown icmp type (255) icmpcode=255
> ----
> type=NETFILTER_PKT msg=audit(01/27/2017 08:03:35.657:187) : action=ACCEPT hook=INPUT len=80 inif=lo outif=? mark=0xf80a9dd7 smac=? dmac=? macproto=UNKNOWN trunc=-1 saddr=::1 daddr=::1 ipid=-1 proto=tcp frag=-1 trunc=-1 sport=38188 dport=42424 icmptype=unknown icmp type (255) icmpcode=255
> ----
> type=NETFILTER_PKT msg=audit(01/27/2017 08:03:35.659:188) : action=ACCEPT hook=INPUT len=31 inif=lo outif=? mark=0xa6d8d4ac smac=? dmac=? macproto=UNKNOWN trunc=-1 saddr=127.0.0.1 daddr=127.0.0.1 ipid=46304 proto=udp frag=255 trunc=-1 sport=60095 dport=42424 icmptype=unknown icmp type (255) icmpcode=255
> ----
> type=NETFILTER_PKT msg=audit(01/27/2017 08:03:35.661:189) : action=ACCEPT hook=INPUT len=51 inif=lo outif=? mark=0x3f0d6054 smac=? dmac=? macproto=UNKNOWN trunc=-1 saddr=::1 daddr=::1 ipid=-1 proto=udp frag=-1 trunc=-1 sport=43818 dport=42424 icmptype=unknown icmp type (255) icmpcode=255
> ----
Here are the raw messages:
----
time->Fri Jan 27 08:03:35 2017
type=NETFILTER_PKT msg=audit(1485522215.649:183): action=0 hook=3 len=84 inif=? outif=lo mark=0xa044a1d4 smac=? dmac=? macproto=0xffff trunc=-1 saddr=127.0.0.1 daddr=127.0.0.1 ipid=26581 proto=1 frag=255 trunc=-1 sport=65535 dport=65535 icmptype=8 icmpcode=0
----
time->Fri Jan 27 08:03:35 2017
type=NETFILTER_PKT msg=audit(1485522215.649:184): action=0 hook=1 len=84 inif=lo outif=? mark=0xbadeac28 smac=? dmac=? macproto=0xffff trunc=-1 saddr=127.0.0.1 daddr=127.0.0.1 ipid=26581 proto=1 frag=255 trunc=-1 sport=65535 dport=65535 icmptype=8 icmpcode=0
----
time->Fri Jan 27 08:03:35 2017
type=NETFILTER_PKT msg=audit(1485522215.652:185): action=0 hook=1 len=104 inif=lo outif=? mark=0xb404724 smac=? dmac=? macproto=0xffff trunc=-1 saddr=::1 daddr=::1 ipid=-1 proto=58 frag=-1 trunc=-1 sport=65535 dport=65535 icmptype=128 icmpcode=0
----
time->Fri Jan 27 08:03:35 2017
type=NETFILTER_PKT msg=audit(1485522215.655:186): action=0 hook=1 len=60 inif=lo outif=? mark=0xe2bd8098 smac=? dmac=? macproto=0xffff trunc=-1 saddr=127.0.0.1 daddr=127.0.0.1 ipid=29381 proto=6 frag=255 trunc=-1 sport=51064 dport=42424 icmptype=255 icmpcode=255
----
time->Fri Jan 27 08:03:35 2017
type=NETFILTER_PKT msg=audit(1485522215.657:187): action=0 hook=1 len=80 inif=lo outif=? mark=0xf80a9dd7 smac=? dmac=? macproto=0xffff trunc=-1 saddr=::1 daddr=::1 ipid=-1 proto=6 frag=-1 trunc=-1 sport=38188 dport=42424 icmptype=255 icmpcode=255
----
time->Fri Jan 27 08:03:35 2017
type=NETFILTER_PKT msg=audit(1485522215.659:188): action=0 hook=1 len=31 inif=lo outif=? mark=0xa6d8d4ac smac=? dmac=? macproto=0xffff trunc=-1 saddr=127.0.0.1 daddr=127.0.0.1 ipid=46304 proto=17 frag=255 trunc=-1 sport=60095 dport=42424 icmptype=255 icmpcode=255
----
time->Fri Jan 27 08:03:35 2017
type=NETFILTER_PKT msg=audit(1485522215.661:189): action=0 hook=1 len=51 inif=lo outif=? mark=0x3f0d6054 smac=? dmac=? macproto=0xffff trunc=-1 saddr=::1 daddr=::1 ipid=-1 proto=17 frag=-1 trunc=-1 sport=43818 dport=42424 icmptype=255 icmpcode=255
----
> > -Steve
> >
> >
> > > Signed-off-by: Richard Guy Briggs <rgb at redhat.com>
> > > ---
> > > net/netfilter/xt_AUDIT.c | 92
> > > +++++++++++++++++++++++++++++++++------------- 1 files changed, 66
> > > insertions(+), 26 deletions(-)
> > >
> > > diff --git a/net/netfilter/xt_AUDIT.c b/net/netfilter/xt_AUDIT.c
> > > index 4973cbd..8089ec2 100644
> > > --- a/net/netfilter/xt_AUDIT.c
> > > +++ b/net/netfilter/xt_AUDIT.c
> > > @@ -31,24 +31,41 @@ MODULE_ALIAS("ip6t_AUDIT");
> > > MODULE_ALIAS("ebt_AUDIT");
> > > MODULE_ALIAS("arpt_AUDIT");
> > >
> > > +struct nfpkt_par {
> > > + int ipv;
> > > + int iptrunc;
> > > + const void *saddr;
> > > + const void *daddr;
> > > + u16 ipid;
> > > + u8 proto;
> > > + u8 frag;
> > > + int ptrunc;
> > > + u16 sport;
> > > + u16 dport;
> > > + u8 icmpt;
> > > + u8 icmpc;
> > > +};
> > > +
> > > static void audit_proto(struct audit_buffer *ab, struct sk_buff *skb,
> > > - unsigned int proto, unsigned int offset)
> > > + unsigned int proto, unsigned int offset,
> > > struct nfpkt_par *apar) {
> > > switch (proto) {
> > > case IPPROTO_TCP:
> > > case IPPROTO_UDP:
> > > - case IPPROTO_UDPLITE: {
> > > + case IPPROTO_UDPLITE:
> > > + case IPPROTO_DCCP:
> > > + case IPPROTO_SCTP: {
> > > const __be16 *pptr;
> > > __be16 _ports[2];
> > >
> > > pptr = skb_header_pointer(skb, offset,
> > > sizeof(_ports), _ports); if (pptr == NULL) {
> > > - audit_log_format(ab, " truncated=1");
> > > + apar->ptrunc = 1;
> > > return;
> > > }
> > > + apar->sport = ntohs(pptr[0]);
> > > + apar->dport = ntohs(pptr[1]);
> > >
> > > - audit_log_format(ab, " sport=%hu dport=%hu",
> > > - ntohs(pptr[0]), ntohs(pptr[1]));
> > > }
> > > break;
> > >
> > > @@ -59,41 +76,43 @@ static void audit_proto(struct audit_buffer *ab,
> > > struct sk_buff *skb,
> > > iptr = skb_header_pointer(skb, offset, sizeof(_ih),
> > > &_ih); if (iptr == NULL) {
> > > - audit_log_format(ab, " truncated=1");
> > > + apar->ptrunc = 1;
> > > return;
> > > }
> > > -
> > > - audit_log_format(ab, " icmptype=%hhu icmpcode=%hhu",
> > > - iptr[0], iptr[1]);
> > > + apar->icmpt = iptr[0];
> > > + apar->icmpc = iptr[1];
> > >
> > > }
> > > break;
> > > }
> > > }
> > >
> > > -static void audit_ip4(struct audit_buffer *ab, struct sk_buff *skb)
> > > +static void audit_ip4(struct audit_buffer *ab, struct sk_buff *skb,
> > > struct nfpkt_par *apar) {
> > > struct iphdr _iph;
> > > const struct iphdr *ih;
> > >
> > > + apar->ipv = 4;
> > > ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph);
> > > if (!ih) {
> > > - audit_log_format(ab, " truncated=1");
> > > + apar->iptrunc = 1;
> > > return;
> > > }
> > >
> > > - audit_log_format(ab, " saddr=%pI4 daddr=%pI4 ipid=%hu
> > > proto=%hhu",
> > > - &ih->saddr, &ih->daddr, ntohs(ih->id), ih->protocol);
> > > + apar->saddr = &ih->saddr;
> > > + apar->daddr = &ih->daddr;
> > > + apar->ipid = ntohs(ih->id);
> > > + apar->proto = ih->protocol;
> > >
> > > if (ntohs(ih->frag_off) & IP_OFFSET) {
> > > - audit_log_format(ab, " frag=1");
> > > + apar->frag = 1;
> > > return;
> > > }
> > >
> > > - audit_proto(ab, skb, ih->protocol, ih->ihl * 4);
> > > + audit_proto(ab, skb, ih->protocol, ih->ihl * 4, apar);
> > > }
> > >
> > > -static void audit_ip6(struct audit_buffer *ab, struct sk_buff *skb)
> > > +static void audit_ip6(struct audit_buffer *ab, struct sk_buff *skb,
> > > struct nfpkt_par *apar) {
> > > struct ipv6hdr _ip6h;
> > > const struct ipv6hdr *ih;
> > > @@ -101,9 +120,10 @@ static void audit_ip6(struct audit_buffer *ab,
> > > struct sk_buff *skb) __be16 frag_off;
> > > int offset;
> > >
> > > + apar->ipv = 6;
> > > ih = skb_header_pointer(skb, skb_network_offset(skb),
> > > sizeof(_ip6h), &_ip6h); if (!ih) {
> > > - audit_log_format(ab, " truncated=1");
> > > + apar->iptrunc = 1;
> > > return;
> > > }
> > >
> > > @@ -111,11 +131,12 @@ static void audit_ip6(struct audit_buffer *ab,
> > > struct sk_buff *skb) offset = ipv6_skip_exthdr(skb,
> > > skb_network_offset(skb) + sizeof(_ip6h), &nexthdr, &frag_off);
> > >
> > > - audit_log_format(ab, " saddr=%pI6c daddr=%pI6c proto=%hhu",
> > > - &ih->saddr, &ih->daddr, nexthdr);
> > > + apar->saddr = &ih->saddr;
> > > + apar->daddr = &ih->daddr;
> > > + apar->proto = nexthdr;
> > >
> > > if (offset)
> > > - audit_proto(ab, skb, nexthdr, offset);
> > > + audit_proto(ab, skb, nexthdr, offset, apar);
> > > }
> > >
> > > static unsigned int
> > > @@ -123,6 +144,9 @@ audit_tg(struct sk_buff *skb, const struct
> > > xt_action_param *par) {
> > > const struct xt_audit_info *info = par->targinfo;
> > > struct audit_buffer *ab;
> > > + struct nfpkt_par apar = {
> > > + -1, -1, NULL, NULL, -1, -1, -1, -1, -1, -1, -1, -1
> > > + };
> > >
> > > if (audit_enabled == 0)
> > > goto errout;
> > > @@ -136,8 +160,7 @@ audit_tg(struct sk_buff *skb, const struct
> > > xt_action_param *par) par->in ? par->in->name : "?",
> > > par->out ? par->out->name : "?");
> > >
> > > - if (skb->mark)
> > > - audit_log_format(ab, " mark=%#x", skb->mark);
> > > + audit_log_format(ab, " mark=%#x", skb->mark ?: -1);
> > >
> > > if (skb->dev && skb->dev->type == ARPHRD_ETHER) {
> > > audit_log_format(ab, " smac=%pM dmac=%pM
> > > macproto=0x%04x", @@ -147,25 +170,42 @@ audit_tg(struct sk_buff *skb,
> > > const struct xt_action_param *par) if (par->family == NFPROTO_BRIDGE)
> > > { switch (eth_hdr(skb)->h_proto) {
> > > case htons(ETH_P_IP):
> > > - audit_ip4(ab, skb);
> > > + audit_ip4(ab, skb, &apar);
> > > break;
> > >
> > > case htons(ETH_P_IPV6):
> > > - audit_ip6(ab, skb);
> > > + audit_ip6(ab, skb, &apar);
> > > break;
> > > }
> > > }
> > > + } else {
> > > + audit_log_format(ab, " smac=? dmac=?
> > > macproto=0xffff"); }
> > >
> > > switch (par->family) {
> > > case NFPROTO_IPV4:
> > > - audit_ip4(ab, skb);
> > > + audit_ip4(ab, skb, &apar);
> > > break;
> > >
> > > case NFPROTO_IPV6:
> > > - audit_ip6(ab, skb);
> > > + audit_ip6(ab, skb, &apar);
> > > + break;
> > > + }
> > > +
> > > + switch (apar.ipv) {
> > > + case 4:
> > > + audit_log_format(ab, " trunc=%d saddr=%pI4
> > > daddr=%pI4 ipid=%hu proto=%hhu frag=%d",
> > > + apar.iptrunc, apar.saddr, apar.daddr,
> > > apar.ipid, apar.proto, apar.frag);
> > > + break;
> > > + case 6:
> > > + audit_log_format(ab, " trunc=%d saddr=%pI6c
> > > daddr=%pI6c ipid=-1 proto=%hhu frag=-1",
> > > + apar.iptrunc, apar.saddr, apar.daddr,
> > > apar.proto); break;
> > > + default:
> > > + audit_log_format(ab, " trunc=-1 saddr=? daddr=?
> > > ipid=-1 proto=-1 frag=-1"); }
> > > + audit_log_format(ab, " trunc=%d sport=%hu dport=%hu
> > > icmptype=%hhu icmpcode=%hhu",
> > > + apar.ptrunc, apar.sport, apar.dport, apar.icmpt,
> > > apar.icmpc);
> > > #ifdef CONFIG_NETWORK_SECMARK
> > > if (skb->secmark)
> >
>
> - RGB
>
> --
> Richard Guy Briggs <rgb at redhat.com>
> Kernel Security Engineering, Base Operating Systems, Red Hat
> Remote, Ottawa, Canada
> Voice: +1.647.777.2635, Internal: (81) 32635
- RGB
--
Richard Guy Briggs <rgb at redhat.com>
Kernel Security Engineering, Base Operating Systems, Red Hat
Remote, Ottawa, Canada
Voice: +1.647.777.2635, Internal: (81) 32635
More information about the Linux-audit
mailing list