// SPDX-License-Identifier: GPL-2.0-only
/* (C) 1999-2001 Paul `Rusty' Russell
* (C) 2002-2004 Netfilter Core Team <[email protected]>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/skbuff.h>
#include <linux/if_arp.h>
#include <linux/ip.h>
#include <net/ipv6.h>
#include <net/icmp.h>
#include <net/udp.h>
#include <net/tcp.h>
#include <net/route.h>
#include <linux/netfilter.h>
#include <linux/netfilter_bridge.h>
#include <linux/netfilter_ipv6.h>
#include <linux/netfilter/xt_LOG.h>
#include <net/netfilter/nf_log.h>
static const struct nf_loginfo default_loginfo = {
.type = NF_LOG_TYPE_LOG,
.u = {
.log = {
.level = LOGLEVEL_NOTICE,
.logflags = NF_LOG_DEFAULT_MASK,
},
},
};
struct arppayload {
unsigned char mac_src[ETH_ALEN];
unsigned char ip_src[4];
unsigned char mac_dst[ETH_ALEN];
unsigned char ip_dst[4];
};
/* Guard against containers flooding syslog. */
static bool nf_log_allowed(const struct net *net)
{
return net_eq(net, &init_net) || sysctl_nf_log_all_netns;
}
static void nf_log_dump_vlan(struct nf_log_buf *m, const struct sk_buff *skb)
{
u16 vid;
if (!skb_vlan_tag_present(skb))
return;
vid = skb_vlan_tag_get(skb);
nf_log_buf_add(m, "VPROTO=%04x VID=%u ", ntohs(skb->vlan_proto), vid);
}
static void noinline_for_stack
dump_arp_packet(struct nf_log_buf *m,
const struct nf_loginfo *info,
const struct sk_buff *skb, unsigned int nhoff)
{
const struct arppayload *ap;
struct arppayload _arpp;
const struct arphdr *ah;
unsigned int logflags;
struct arphdr _arph;
ah = skb_header_pointer(skb, nhoff, sizeof(_arph), &_arph);
if (!ah) {
nf_log_buf_add(m, "TRUNCATED");
return;
}
if (info->type == NF_LOG_TYPE_LOG)
logflags = info->u.log.logflags;
else
logflags = NF_LOG_DEFAULT_MASK;
if (logflags & NF_LOG_MACDECODE) {
nf_log_buf_add(m, "MACSRC=%pM MACDST=%pM ",
eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest);
nf_log_dump_vlan(m, skb);
nf_log_buf_add(m, "MACPROTO=%04x ",
ntohs(eth_hdr(skb)->h_proto));
}
nf_log_buf_add(m, "ARP HTYPE=%d PTYPE=0x%04x OPCODE=%d",
ntohs(ah->ar_hrd), ntohs(ah->ar_pro), ntohs(ah->ar_op));
/* If it's for Ethernet and the lengths are OK, then log the ARP
* payload.
*/
if (ah->ar_hrd != htons(ARPHRD_ETHER) ||
ah->ar_hln != ETH_ALEN ||
ah->ar_pln != sizeof(__be32))
return;
ap = skb_header_pointer(skb, nhoff + sizeof(_arph), sizeof(_arpp), &_arpp);
if (!ap) {
nf_log_buf_add(m, " INCOMPLETE [%zu bytes]",
skb->len - sizeof(_arph));
return;
}
nf_log_buf_add(m, " MACSRC=%pM IPSRC=%pI4 MACDST=%pM IPDST=%pI4",
ap->mac_src, ap->ip_src, ap->mac_dst, ap->ip_dst);
}
static void
nf_log_dump_packet_common(struct nf_log_buf *m, u8 pf,
unsigned int hooknum, const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const struct nf_loginfo *loginfo, const char *prefix,
struct net *net)
{
const struct net_device *physoutdev __maybe_unused;
const struct net_device *physindev __maybe_unused;
nf_log_buf_add(m, KERN_SOH "%c%sIN=%s OUT=%s ",
'0' + loginfo->u.log.level, prefix,
in ? in->name : "",
out ? out->name : "");
#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
physindev = nf_bridge_get_physindev(skb, net);
if (physindev && in != physindev)
nf_log_buf_add(m, "PHYSIN=%s ", physindev->name);
physoutdev = nf_bridge_get_physoutdev(skb);
if (physoutdev && out != physoutdev)
nf_log_buf_add(m, "PHYSOUT=%s ", physoutdev->name);
#endif
}
static void nf_log_arp_packet(struct net *net, u_int8_t pf,
unsigned int hooknum, const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const struct nf_loginfo *loginfo,
const char *prefix)
{
struct nf_log_buf *m;
if (!nf_log_allowed(net))
return;
m = nf_log_buf_open();
if (!loginfo)
loginfo = &default_loginfo;
nf_log_dump_packet_common(m, pf, hooknum, skb, in, out, loginfo,
prefix, net);
dump_arp_packet(m, loginfo, skb, skb_network_offset(skb));
nf_log_buf_close(m);
}
static struct nf_logger nf_arp_logger __read_mostly = {
.name = "nf_log_arp",
.type = NF_LOG_TYPE_LOG,
.logfn = nf_log_arp_packet,
.me = THIS_MODULE,
};
static void nf_log_dump_sk_uid_gid(struct net *net, struct nf_log_buf *m,
struct sock *sk)
{
if (!sk || !sk_fullsock(sk) || !net_eq(net, sock_net(sk)))
return;
read_lock_bh(&sk->sk_callback_lock);
if (sk->sk_socket && sk->sk_socket->file) {
const struct cred *cred = sk->sk_socket->file->f_cred;
nf_log_buf_add(m, "UID=%u GID=%u ",
from_kuid_munged(&init_user_ns, cred->fsuid),
from_kgid_munged(&init_user_ns, cred->fsgid));
}
read_unlock_bh(&sk->sk_callback_lock);
}
static noinline_for_stack int
nf_log_dump_tcp_header(struct nf_log_buf *m,
const struct sk_buff *skb,
u8 proto, int fragment,
unsigned int offset,
unsigned int logflags)
{
struct tcphdr _tcph;
const struct tcphdr *th;
/* Max length: 10 "PROTO=TCP " */
nf_log_buf_add(m, "PROTO=TCP ");
if (fragment)
return 0;
/* Max length: 25 "INCOMPLETE [65535 bytes] " */
th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
if (!th) {
nf_log_buf_add(m, "INCOMPLETE [%u bytes] ", skb->len - offset);
return 1;
}
/* Max length: 20 "SPT=65535 DPT=65535 " */
nf_log_buf_add(m, "SPT=%u DPT=%u ",
ntohs(th->source), ntohs(th->dest));
/* Max length: 30 "SEQ=4294967295 ACK=4294967295 " */
if (logflags & NF_LOG_TCPSEQ) {
nf_log_buf_add(m, "SEQ=%u ACK=%u ",
ntohl(th->seq), ntohl(th->ack_seq));
}
/* Max length: 13 "WINDOW=65535 " */
nf_log_buf_add(m, "WINDOW=%u ", ntohs(th->window));
/* Max length: 9 "RES=0x3C " */
nf_log_buf_add(m, "RES=0x%02x ", (u_int8_t)(ntohl(tcp_flag_word(th) &
TCP_RESERVED_BITS) >> 22));
/* Max length: 32 "CWR ECE URG ACK PSH RST SYN FIN " */
if (th->cwr)
nf_log_buf_add(m, "CWR ");
if (th->ece)
nf_log_buf_add(m, "ECE ");
if (th->urg)
nf_log_buf_add(m, "URG ");
if (th->ack)
nf_log_buf_add(m, "ACK ");
if (th->psh)
nf_log_buf_add(m, "PSH ");
if (th->rst)
nf_log_buf_add(m, "RST ");
if (th->syn)
nf_log_buf_add(m, "SYN ");
if (th->fin)
nf_log_buf_add(m, "FIN ");
/* Max length: 11 "URGP=65535 " */
nf_log_buf_add(m, "URGP=%u ", ntohs(th->urg_ptr));
if ((logflags & NF_LOG_TCPOPT) && th->doff * 4 > sizeof(struct tcphdr)) {
unsigned int optsize = th->doff * 4 - sizeof(struct tcphdr);
u8 _opt[60 - sizeof(struct tcphdr)];
unsigned int i;
const u8 *op;
op = skb_header_pointer(skb, offset + sizeof(struct tcphdr),
optsize, _opt);
if (!op) {
nf_log_buf_add(m, "OPT (TRUNCATED)");
return 1;
}
/* Max length: 127 "OPT (" 15*4*2chars ") " */
nf_log_buf_add(m, "OPT (");
for (i = 0; i < optsize; i++)
nf_log_buf_add(m, "%02X", op[i]);
nf_log_buf_add(m, ") ");
}
return 0;
}
static noinline_for_stack int
nf_log_dump_udp_header(struct nf_log_buf *m,
const struct sk_buff *skb,
u8 proto, int fragment,
unsigned int offset)
{
struct udphdr _udph;
const struct udphdr *uh;
if (proto == IPPROTO_UDP)
/* Max length: 10 "PROTO=UDP " */
nf_log_buf_add(m, "PROTO=UDP ");
else /* Max length: 14 "PROTO=UDPLITE " */
nf_log_buf_add(m, "PROTO=UDPLITE ");
if (fragment)
goto out;
/* Max length: 25 "INCOMPLETE [65535 bytes] " */
uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
if (!uh) {
nf_log_buf_add(m, "INCOMPLETE [%u bytes] ", skb->len - offset);
return 1;
}
/* Max length: 20 "SPT=65535 DPT=65535 " */
nf_log_buf_add(m, "SPT=%u DPT=%u LEN=%u ",
ntohs(uh->source), ntohs(uh->dest), ntohs(uh->len));
out:
return 0;
}
/* One level of recursion won't kill us */
static noinline_for_stack void
dump_ipv4_packet(struct net *net, struct nf_log_buf *m,
const struct nf_loginfo *info,
const struct sk_buff *skb, unsigned int iphoff)
{
const struct iphdr *ih;
unsigned int logflags;
struct iphdr _iph;
if (info->type == NF_LOG_TYPE_LOG)
logflags = info->u.log.logflags;
else
logflags = NF_LOG_DEFAULT_MASK;
ih = skb_header_pointer(skb, iphoff, sizeof(_iph), &_iph);
if (!ih) {
nf_log_buf_add(m, "TRUNCATED");
return;
}
/* Important fields:
* TOS, len, DF/MF, fragment offset, TTL, src, dst, options.
* Max length: 40 "SRC=255.255.255.255 DST=255.255.255.255 "
*/
nf_log_buf_add(m, "SRC=%pI4 DST=%pI4 ", &ih->saddr, &ih->daddr);
/* Max length: 46 "LEN=65535 TOS=0xFF PREC=0xFF TTL=255 ID=65535 " */
nf_log_buf_add(m, "LEN=%u TOS=0x%02X PREC=0x%02X TTL=%u ID=%u ",
iph_totlen(skb, ih), ih->tos & IPTOS_TOS_MASK,
ih->tos & IPTOS_PREC_MASK, ih->ttl, ntohs(ih->id));
/* Max length: 6 "CE DF MF " */
if (ntohs(ih->frag_off) & IP_CE)
nf_log_buf_add(m, "CE ");
if (ntohs(ih->frag_off) & IP_DF)
nf_log_buf_add(m, "DF ");
if (ntohs(ih->frag_off) & IP_MF)
nf_log_buf_add(m, "MF ");
/* Max length: 11 "FRAG:65535 " */
if (ntohs(ih->frag_off) & IP_OFFSET)
nf_log_buf_add(m, "FRAG:%u ", ntohs(ih->frag_off) & IP_OFFSET);
if ((logflags & NF_LOG_IPOPT) &&
ih->ihl * 4 > sizeof(struct iphdr)) {
unsigned char _opt[4 * 15 - sizeof(struct iphdr)];
const unsigned char *op;
unsigned int i, optsize;
optsize = ih->ihl * 4 - sizeof(struct iphdr);
op = skb_header_pointer(skb, iphoff + sizeof(_iph),
optsize, _opt);
if (!op) {
nf_log_buf_add(m, "TRUNCATED");
return;
}
/* Max length: 127 "OPT (" 15*4*2chars ") " */
nf_log_buf_add(m, "OPT (");
for (i = 0; i < optsize; i++)
nf_log_buf_add(m, "%02X", op[i]);
nf_log_buf_add(m, ") ");
}
switch (ih->protocol) {
case IPPROTO_TCP:
if (nf_log_dump_tcp_header(m, skb, ih->protocol,
ntohs(ih->frag_off) & IP_OFFSET,
iphoff + ih->ihl * 4, logflags))
return;
break;
case IPPROTO_UDP:
case IPPROTO_UDPLITE:
if (nf_log_dump_udp_header(m, skb, ih->protocol,
ntohs(ih->frag_off) & IP_OFFSET,
iphoff + ih->ihl * 4))
return;
break;
case IPPROTO_ICMP: {
static const size_t required_len[NR_ICMP_TYPES + 1] = {
[ICMP_ECHOREPLY] = 4,
[ICMP_DEST_UNREACH] = 8 + sizeof(struct iphdr),
[ICMP_SOURCE_QUENCH] = 8 + sizeof(struct iphdr),
[ICMP_REDIRECT] = 8 + sizeof(struct iphdr),
[ICMP_ECHO] = 4,
[ICMP_TIME_EXCEEDED] = 8 + sizeof(struct iphdr),
[ICMP_PARAMETERPROB] = 8 + sizeof(struct iphdr),
[ICMP_TIMESTAMP] = 20,
[ICMP_TIMESTAMPREPLY] = 20,
[ICMP_ADDRESS] = 12,
[ICMP_ADDRESSREPLY] = 12 };
const struct icmphdr *ich;
struct icmphdr _icmph;
/* Max length: 11 "PROTO=ICMP " */
nf_log_buf_add(m, "PROTO=ICMP ");
if (ntohs(ih->frag_off) & IP_OFFSET)
break;
/* Max length: 25 "INCOMPLETE [65535 bytes] " */
ich = skb_header_pointer(skb, iphoff + ih->ihl * 4,
sizeof(_icmph), &_icmph);
if (!ich) {
nf_log_buf_add(m, "INCOMPLETE [%u bytes] ",
skb->len - iphoff - ih->ihl * 4);
break;
}
/* Max length: 18 "TYPE=255 CODE=255 " */
nf_log_buf_add(m, "TYPE=%u CODE=%u ", ich->type, ich->code);
/* Max length: 25 "INCOMPLETE [65535 bytes] " */
if (ich->type <= NR_ICMP_TYPES &&
required_len[ich->type] &&
skb->len - iphoff - ih->ihl * 4 < required_len[ich->type]) {
nf_log_buf_add(m, "INCOMPLETE [%u bytes] ",
skb->len - iphoff - ih->ihl * 4);
break;
}
switch (ich->type) {
case ICMP_ECHOREPLY:
case ICMP_ECHO:
/* Max length: 19 "ID=65535 SEQ=65535 " */
nf_log_buf_add(m, "ID=%u SEQ=%u ",
ntohs(ich->un.echo.id),
ntohs(ich->un.echo.sequence));
break;
case ICMP_PARAMETERPROB:
/* Max length: 14 "PARAMETER=255 " */
nf_log_buf_add(m, "PARAMETER=%u ",
ntohl(ich->un.gateway) >> 24);
break;
case ICMP_REDIRECT:
/* Max length: 24 "GATEWAY=255.255.255.255 " */
nf_log_buf_add(m, "GATEWAY=%pI4 ", &ich->un.gateway);
fallthrough;
case ICMP_DEST_UNREACH:
case ICMP_SOURCE_QUENCH:
case ICMP_TIME_EXCEEDED:
/* Max length: 3+maxlen */
if (!iphoff) { /* Only recurse once. */
nf_log_buf_add(m, "[");
dump_ipv4_packet(net, m, info, skb,
iphoff + ih->ihl * 4 + sizeof(_icmph));
nf_log_buf_add(m, "] ");
}
/* Max length: 10 "MTU=65535 " */
if (ich->type == ICMP_DEST_UNREACH &&
ich->code == ICMP_FRAG_NEEDED) {
nf_log_buf_add(m, "MTU=%u ",
ntohs(ich->un.frag.mtu));
}
}
break;
}
/* Max Length */
case IPPROTO_AH: {
const struct ip_auth_hdr *ah;
struct ip_auth_hdr _ahdr;
if (ntohs(ih->frag_off) & IP_OFFSET)
break;
/* Max length: 9 "PROTO=AH " */
nf_log_buf_add(m, "PROTO=AH ");
/* Max length: 25 "INCOMPLETE [65535 bytes] " */
ah = skb_header_pointer(skb, iphoff + ih->ihl * 4,
sizeof(_ahdr), &_ahdr);
if (!ah) {
nf_log_buf_add(m, "INCOMPLETE [%u bytes] ",
skb->len - iphoff - ih->ihl * 4);
break;
}
/* Length: 15 "SPI=0xF1234567 " */
nf_log_buf_add(m, "SPI=0x%x ", ntohl(ah->spi));
break;
}
case IPPROTO_ESP: {
const struct ip_esp_hdr *eh;
struct ip_esp_hdr _esph;
/* Max length: 10 "PROTO=ESP " */
nf_log_buf_add(m, "PROTO=ESP ");
if (ntohs(ih->frag_off) & IP_OFFSET)
break;
/* Max length: 25 "INCOMPLETE [65535 bytes] " */
eh = skb_header_pointer(skb, iphoff + ih->ihl * 4,
sizeof(_esph), &_esph);
if (!eh) {
nf_log_buf_add(m, "INCOMPLETE [%u bytes] ",
skb->len - iphoff - ih->ihl * 4);
break;
}
/* Length: 15 "SPI=0xF1234567 " */
nf_log_buf_add(m, "SPI=0x%x ", ntohl(eh->spi));
break;
}
/* Max length: 10 "PROTO 255 " */
default:
nf_log_buf_add(m, "PROTO=%u ", ih->protocol);
}
/* Max length: 15 "UID=4294967295 " */
if ((logflags & NF_LOG_UID) && !iphoff)
nf_log_dump_sk_uid_gid(net, m, skb->sk);
/* Max length: 16 "MARK=0xFFFFFFFF " */
if (!iphoff && skb->mark)
nf_log_buf_add(m, "MARK=0x%x ", skb->mark);
/* Proto Max log string length */
/* IP: 40+46+6+11+127 = 230 */
/* TCP: 10+max(25,20+30+13+9+32+11+127) = 252 */
/* UDP: 10+max(25,20) = 35 */
/* UDPLITE: 14+max(25,20) = 39 */
/* ICMP: 11+max(25, 18+25+max(19,14,24+3+n+10,3+n+10)) = 91+n */
/* ESP: 10+max(25)+15 = 50 */
/* AH: 9+max(25)+15 = 49 */
/* unknown: 10 */
/* (ICMP allows recursion one level deep) */
/* maxlen = IP + ICMP + IP + max(TCP,UDP,ICMP,unknown) */
/* maxlen = 230+ 91 + 230 + 252 = 803 */
}
static noinline_for_stack void
dump_ipv6_packet(struct net *net, struct nf_log_buf *m,
const struct nf_loginfo *info,
const struct sk_buff *skb, unsigned int ip6hoff,
int recurse)
{
const struct ipv6hdr *ih;
unsigned int hdrlen = 0;
unsigned int logflags;
struct ipv6hdr _ip6h;
unsigned int ptr;
u8 currenthdr;
int fragment;
if (info->type == NF_LOG_TYPE_LOG)
logflags = info->u.log.logflags;
else
logflags = NF_LOG_DEFAULT_MASK;
ih = skb_header_pointer(skb, ip6hoff, sizeof(_ip6h), &_ip6h);
if (!ih) {
nf_log_buf_add(m, "TRUNCATED");
return;
}
/* Max length: 88 "SRC=0000.0000.0000.0000.0000.0000.0000.0000 DST=0000.0000.0000.0000.0000.0000.0000.0000 " */
nf_log_buf_add(m, "SRC=%pI6 DST=%pI6 ", &ih->saddr, &ih->daddr);
/* Max length: 44 "LEN=65535 TC=255 HOPLIMIT=255 FLOWLBL=FFFFF " */
nf_log_buf_add(m, "LEN=%zu TC=%u HOPLIMIT=%u FLOWLBL=%u ",
ntohs(ih->payload_len) + sizeof(struct ipv6hdr),
(ntohl(*(__be32 *)ih) & 0x0ff00000) >> 20,
ih->hop_limit,
(ntohl(*(__be32 *)ih) & 0x000fffff));
fragment = 0;
ptr = ip6hoff + sizeof(struct ipv6hdr);
currenthdr = ih->nexthdr;
while (currenthdr != NEXTHDR_NONE && nf_ip6_ext_hdr(currenthdr)) {
struct ipv6_opt_hdr _hdr;
const struct ipv6_opt_hdr *hp;
hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr);
if (!hp) {
nf_log_buf_add(m, "TRUNCATED");
return;
}
/* Max length: 48 "OPT (...) " */
if (logflags & NF_LOG_IPOPT)
nf_log_buf_add(m, "OPT ( ");
switch (currenthdr) {
case IPPROTO_FRAGMENT: {
struct frag_hdr _fhdr;
const struct frag_hdr *fh;
nf_log_buf_add(m, "FRAG:");
fh = skb_header_pointer(skb, ptr, sizeof(_fhdr),
&_fhdr);
if (!fh) {
nf_log_buf_add(m, "TRUNCATED ");
return;
}
/* Max length: 6 "65535 " */
nf_log_buf_add(m, "%u ", ntohs(fh->frag_off) & 0xFFF8);
/* Max length: 11 "INCOMPLETE " */
if (fh->frag_off & htons(0x0001))
nf_log_buf_add(m, "INCOMPLETE ");
nf_log_buf_add(m, "ID:%08x ",
ntohl(fh->identification));
if (ntohs(fh->frag_off) & 0xFFF8)
fragment = 1;
hdrlen = 8;
break;
}
case IPPROTO_DSTOPTS:
case IPPROTO_ROUTING:
case IPPROTO_HOPOPTS:
if (fragment) {
if (logflags & NF_LOG_IPOPT)
nf_log_buf_add(m, ")");
return;
}
hdrlen = ipv6_optlen(hp);
break;
/* Max Length */
case IPPROTO_AH:
if (logflags & NF_LOG_IPOPT) {
struct ip_auth_hdr _ahdr;
const struct ip_auth_hdr *ah;
/* Max length: 3 "AH " */
nf_log_buf_add(m, "AH ");
if (fragment) {
nf_log_buf_add(m, ")");
return;
}
ah = skb_header_pointer(skb, ptr, sizeof(_ahdr),
&_ahdr);
if (!ah) {
/* Max length: 26 "INCOMPLETE [65535 bytes] )" */
nf_log_buf_add(m, "INCOMPLETE [%u bytes] )",
skb->len - ptr);
return;
}
/* Length: 15 "SPI=0xF1234567 */
nf_log_buf_add(m, "SPI=0x%x ", ntohl(ah->spi));
}
hdrlen = ipv6_authlen(hp);
break;
case IPPROTO_ESP:
if (logflags & NF_LOG_IPOPT) {
struct ip_esp_hdr _esph;
const struct ip_esp_hdr *eh;
/* Max length: 4 "ESP " */
nf_log_buf_add(m, "ESP ");
if (fragment) {
nf_log_buf_add(m, ")");
return;
}
/* Max length: 26 "INCOMPLETE [65535 bytes] )" */
eh = skb_header_pointer(skb, ptr, sizeof(_esph),
&_esph);
if (!eh) {
nf_log_buf_add(m, "INCOMPLETE [%u bytes] )",
skb->len - ptr);
return;
}
/* Length: 16 "SPI=0xF1234567 )" */
nf_log_buf_add(m, "SPI=0x%x )",
ntohl(eh->spi));
}
return;
default:
/* Max length: 20 "Unknown Ext Hdr 255" */
nf_log_buf_add(m, "Unknown Ext Hdr %u", currenthdr);
return;
}
if (logflags & NF_LOG_IPOPT)
nf_log_buf_add(m, ") ");
currenthdr = hp->nexthdr;
ptr += hdrlen;
}
switch (currenthdr) {
case IPPROTO_TCP:
if (nf_log_dump_tcp_header(m, skb, currenthdr, fragment,
ptr, logflags))
return;
break;
case IPPROTO_UDP:
case IPPROTO_UDPLITE:
if (nf_log_dump_udp_header(m, skb, currenthdr, fragment, ptr))
return;
break;
case IPPROTO_ICMPV6: {
struct icmp6hdr _icmp6h;
const struct icmp6hdr *ic;
/* Max length: 13 "PROTO=ICMPv6 " */
nf_log_buf_add(m, "PROTO=ICMPv6 ");
if (fragment)
break;
/* Max length: 25 "INCOMPLETE [65535 bytes] " */
ic = skb_header_pointer(skb, ptr, sizeof(_icmp6h), &_icmp6h);
if (!ic) {
nf_log_buf_add(m, "INCOMPLETE [%u bytes] ",
skb->len - ptr);
return;
}
/* Max length: 18 "TYPE=255 CODE=255 " */
nf_log_buf_add(m, "TYPE=%u CODE=%u ",
ic->icmp6_type, ic->icmp6_code);
switch (ic->icmp6_type) {
case ICMPV6_ECHO_REQUEST:
case ICMPV6_ECHO_REPLY:
/* Max length: 19 "ID=65535 SEQ=65535 " */
nf_log_buf_add(m, "ID=%u SEQ=%u ",
ntohs(ic->icmp6_identifier),
ntohs(ic->icmp6_sequence));
break;
case ICMPV6_MGM_QUERY:
case ICMPV6_MGM_REPORT:
case ICMPV6_MGM_REDUCTION:
break;
case ICMPV6_PARAMPROB:
/* Max length: 17 "POINTER=ffffffff " */
nf_log_buf_add(m, "POINTER=%08x ",
ntohl(ic->icmp6_pointer));
fallthrough;
case ICMPV6_DEST_UNREACH:
case ICMPV6_PKT_TOOBIG:
case ICMPV6_TIME_EXCEED:
/* Max length: 3+maxlen */
if (recurse) {
nf_log_buf_add(m, "[");
dump_ipv6_packet(net, m, info, skb,
ptr + sizeof(_icmp6h), 0);
nf_log_buf_add(m, "] ");
}
/* Max length: 10 "MTU=65535 " */
if (ic->icmp6_type == ICMPV6_PKT_TOOBIG) {
nf_log_buf_add(m, "MTU=%u ",
ntohl(ic->icmp6_mtu));
}
}
break;
}
/* Max length: 10 "PROTO=255 " */
default:
nf_log_buf_add(m, "PROTO=%u ", currenthdr);
}
/* Max length: 15 "UID=4294967295 " */
if ((logflags & NF_LOG_UID) && recurse)
nf_log_dump_sk_uid_gid(net, m, skb->sk);
/* Max length: 16 "MARK=0xFFFFFFFF " */
if (recurse && skb->mark)
nf_log_buf_add(m, "MARK=0x%x ", skb->mark);
}
static void dump_mac_header(struct nf_log_buf *m,
const struct nf_loginfo *info,
const struct sk_buff *skb)
{
struct net_device *dev = skb->dev;
unsigned int logflags = 0;
if (info->type == NF_LOG_TYPE_LOG)
logflags = info->u.log.logflags;
if (!(logflags & NF_LOG_MACDECODE))
goto fallback;
switch (dev->type) {
case ARPHRD_ETHER:
nf_log_buf_add(m, "MACSRC=%pM MACDST=%pM ",
eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest);
nf_log_dump_vlan(m, skb);
nf_log_buf_add(m, "MACPROTO=%04x ",
ntohs(eth_hdr(skb)->h_proto));
return;
default:
break;
}
fallback:
nf_log_buf_add(m, "MAC=");
if (dev->hard_header_len &&
skb->mac_header != skb->network_header) {
const unsigned char *p = skb_mac_header(skb);
unsigned int i;
if (dev->type == ARPHRD_SIT) {
p -= ETH_HLEN;
if (p < skb->head)
p = NULL;
}
if (p) {
nf_log_buf_add(m, "%02x", *p++);
for (i = 1; i < dev->hard_header_len; i++)
nf_log_buf_add(m, ":%02x", *p++);
}
if (dev->type == ARPHRD_SIT) {
const struct iphdr *iph =
(struct iphdr *)skb_mac_header(skb);
nf_log_buf_add(m, " TUNNEL=%pI4->%pI4", &iph->saddr,
&iph->daddr);
}
}
nf_log_buf_add(m, " ");
}
static void nf_log_ip_packet(struct net *net, u_int8_t pf,
unsigned int hooknum, const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const struct nf_loginfo *loginfo,
const char *prefix)
{
struct nf_log_buf *m;
if (!nf_log_allowed(net))
return;
m = nf_log_buf_open();
if (!loginfo)
loginfo = &default_loginfo;
nf_log_dump_packet_common(m, pf, hooknum, skb, in,
out, loginfo, prefix, net);
if (in)
dump_mac_header(m, loginfo, skb);
dump_ipv4_packet(net, m, loginfo, skb, skb_network_offset(skb));
nf_log_buf_close(m);
}
static struct nf_logger nf_ip_logger __read_mostly = {
.name = "nf_log_ipv4",
.type = NF_LOG_TYPE_LOG,
.logfn = nf_log_ip_packet,
.me = THIS_MODULE,
};
static void nf_log_ip6_packet(struct net *net, u_int8_t pf,
unsigned int hooknum, const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const struct nf_loginfo *loginfo,
const char *prefix)
{
struct nf_log_buf *m;
if (!nf_log_allowed(net))
return;
m = nf_log_buf_open();
if (!loginfo)
loginfo = &default_loginfo;
nf_log_dump_packet_common(m, pf, hooknum, skb, in, out,
loginfo, prefix, net);
if (in)
dump_mac_header(m, loginfo, skb);
dump_ipv6_packet(net, m, loginfo, skb, skb_network_offset(skb), 1);
nf_log_buf_close(m);
}
static struct nf_logger nf_ip6_logger __read_mostly = {
.name = "nf_log_ipv6",
.type = NF_LOG_TYPE_LOG,
.logfn = nf_log_ip6_packet,
.me = THIS_MODULE,
};
static void nf_log_unknown_packet(struct net *net, u_int8_t pf,
unsigned int hooknum,
const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const struct nf_loginfo *loginfo,
const char *prefix)
{
struct nf_log_buf *m;
if (!nf_log_allowed(net))
return;
m = nf_log_buf_open();
if (!loginfo)
loginfo = &default_loginfo;
nf_log_dump_packet_common(m, pf, hooknum, skb, in, out, loginfo,
prefix, net);
dump_mac_header(m, loginfo, skb);
nf_log_buf_close(m);
}
static void nf_log_netdev_packet(struct net *net, u_int8_t pf,
unsigned int hooknum,
const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const struct nf_loginfo *loginfo,
const char *prefix)
{
switch (skb->protocol) {
case htons(ETH_P_IP):
nf_log_ip_packet(net, pf, hooknum, skb, in, out, loginfo, prefix);
break;
case htons(ETH_P_IPV6):
nf_log_ip6_packet(net, pf, hooknum, skb, in, out, loginfo, prefix);
break;
case htons(ETH_P_ARP):
case htons(ETH_P_RARP):
nf_log_arp_packet(net, pf, hooknum, skb, in, out, loginfo, prefix);
break;
default:
nf_log_unknown_packet(net, pf, hooknum, skb,
in, out, loginfo, prefix);
break;
}
}
static struct nf_logger nf_netdev_logger __read_mostly = {
.name = "nf_log_netdev",
.type = NF_LOG_TYPE_LOG,
.logfn = nf_log_netdev_packet,
.me = THIS_MODULE,
};
static struct nf_logger nf_bridge_logger __read_mostly = {
.name = "nf_log_bridge",
.type = NF_LOG_TYPE_LOG,
.logfn = nf_log_netdev_packet,
.me = THIS_MODULE,
};
static int __net_init nf_log_syslog_net_init(struct net *net)
{
int ret = nf_log_set(net, NFPROTO_IPV4, &nf_ip_logger);
if (ret)
return ret;
ret = nf_log_set(net, NFPROTO_ARP, &nf_arp_logger);
if (ret)
goto err1;
ret = nf_log_set(net, NFPROTO_IPV6, &nf_ip6_logger);
if (ret)
goto err2;
ret = nf_log_set(net, NFPROTO_NETDEV, &nf_netdev_logger);
if (ret)
goto err3;
ret = nf_log_set(net, NFPROTO_BRIDGE, &nf_bridge_logger);
if (ret)
goto err4;
return 0;
err4:
nf_log_unset(net, &nf_netdev_logger);
err3:
nf_log_unset(net, &nf_ip6_logger);
err2:
nf_log_unset(net, &nf_arp_logger);
err1:
nf_log_unset(net, &nf_ip_logger);
return ret;
}
static void __net_exit nf_log_syslog_net_exit(struct net *net)
{
nf_log_unset(net, &nf_ip_logger);
nf_log_unset(net, &nf_arp_logger);
nf_log_unset(net, &nf_ip6_logger);
nf_log_unset(net, &nf_netdev_logger);
nf_log_unset(net, &nf_bridge_logger);
}
static struct pernet_operations nf_log_syslog_net_ops = {
.init = nf_log_syslog_net_init,
.exit = nf_log_syslog_net_exit,
};
static int __init nf_log_syslog_init(void)
{
int ret;
ret = register_pernet_subsys(&nf_log_syslog_net_ops);
if (ret < 0)
return ret;
ret = nf_log_register(NFPROTO_IPV4, &nf_ip_logger);
if (ret < 0)
goto err1;
ret = nf_log_register(NFPROTO_ARP, &nf_arp_logger);
if (ret < 0)
goto err2;
ret = nf_log_register(NFPROTO_IPV6, &nf_ip6_logger);
if (ret < 0)
goto err3;
ret = nf_log_register(NFPROTO_NETDEV, &nf_netdev_logger);
if (ret < 0)
goto err4;
ret = nf_log_register(NFPROTO_BRIDGE, &nf_bridge_logger);
if (ret < 0)
goto err5;
return 0;
err5:
nf_log_unregister(&nf_netdev_logger);
err4:
nf_log_unregister(&nf_ip6_logger);
err3:
nf_log_unregister(&nf_arp_logger);
err2:
nf_log_unregister(&nf_ip_logger);
err1:
pr_err("failed to register logger\n");
unregister_pernet_subsys(&nf_log_syslog_net_ops);
return ret;
}
static void __exit nf_log_syslog_exit(void)
{
unregister_pernet_subsys(&nf_log_syslog_net_ops);
nf_log_unregister(&nf_ip_logger);
nf_log_unregister(&nf_arp_logger);
nf_log_unregister(&nf_ip6_logger);
nf_log_unregister(&nf_netdev_logger);
nf_log_unregister(&nf_bridge_logger);
}
module_init(nf_log_syslog_init);
module_exit(nf_log_syslog_exit);
MODULE_AUTHOR("Netfilter Core Team <[email protected]>");
MODULE_DESCRIPTION("Netfilter syslog packet logging");
MODULE_LICENSE("GPL");
MODULE_ALIAS("nf_log_arp");
MODULE_ALIAS("nf_log_bridge");
MODULE_ALIAS("nf_log_ipv4");
MODULE_ALIAS("nf_log_ipv6");
MODULE_ALIAS("nf_log_netdev");
MODULE_ALIAS_NF_LOGGER(AF_BRIDGE, 0);
MODULE_ALIAS_NF_LOGGER(AF_INET, 0);
MODULE_ALIAS_NF_LOGGER(3, 0);
MODULE_ALIAS_NF_LOGGER(5, 0); /* NFPROTO_NETDEV */
MODULE_ALIAS_NF_LOGGER(AF_INET6, 0);
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