[NETFILTER]: Extend netfilter logging API

This patch is in preparation to nfnetlink_log:
- loggers now have to register struct nf_logger instead of nf_logfn
- nf_log_unregister() replaced by nf_log_unregister_pf() and
  nf_log_unregister_logger()
- add comment to ip[6]t_LOG.h to assure nobody redefines flags
- add /proc/net/netfilter/nf_log to tell user which logger is currently
  registered for which address family
- if user has configured logging, but no logging backend (logger) is
  available, always spit a message to syslog, not just the first time.
- split ip[6]t_LOG.c into two parts:
  Backend: Always try to register as logger for the respective address family
  Frontend: Always log via nf_log_packet() API
- modify all users of nf_log_packet() to accomodate additional argument

Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Harald Welte
2005-08-09 19:58:27 -07:00
committed by David S. Miller
parent 838ab63649
commit 608c8e4f7b
10 changed files with 299 additions and 125 deletions

View File

@@ -26,10 +26,6 @@ MODULE_AUTHOR("Jan Rekorajski <baggins@pld.org.pl>");
MODULE_DESCRIPTION("IP6 tables LOG target module");
MODULE_LICENSE("GPL");
static unsigned int nflog = 1;
module_param(nflog, int, 0400);
MODULE_PARM_DESC(nflog, "register as internal netfilter logging module");
struct in_device;
#include <net/route.h>
#include <linux/netfilter_ipv6/ip6t_LOG.h>
@@ -44,7 +40,7 @@ struct in_device;
static DEFINE_SPINLOCK(log_lock);
/* One level of recursion won't kill us */
static void dump_packet(const struct ip6t_log_info *info,
static void dump_packet(const struct nf_loginfo *info,
const struct sk_buff *skb, unsigned int ip6hoff,
int recurse)
{
@@ -53,6 +49,12 @@ static void dump_packet(const struct ip6t_log_info *info,
struct ipv6hdr _ip6h, *ih;
unsigned int ptr;
unsigned int hdrlen = 0;
unsigned int logflags;
if (info->type == NF_LOG_TYPE_LOG)
logflags = info->u.log.logflags;
else
logflags = NF_LOG_MASK;
ih = skb_header_pointer(skb, ip6hoff, sizeof(_ip6h), &_ip6h);
if (ih == NULL) {
@@ -84,7 +86,7 @@ static void dump_packet(const struct ip6t_log_info *info,
}
/* Max length: 48 "OPT (...) " */
if (info->logflags & IP6T_LOG_IPOPT)
if (logflags & IP6T_LOG_IPOPT)
printk("OPT ( ");
switch (currenthdr) {
@@ -119,7 +121,7 @@ static void dump_packet(const struct ip6t_log_info *info,
case IPPROTO_ROUTING:
case IPPROTO_HOPOPTS:
if (fragment) {
if (info->logflags & IP6T_LOG_IPOPT)
if (logflags & IP6T_LOG_IPOPT)
printk(")");
return;
}
@@ -127,7 +129,7 @@ static void dump_packet(const struct ip6t_log_info *info,
break;
/* Max Length */
case IPPROTO_AH:
if (info->logflags & IP6T_LOG_IPOPT) {
if (logflags & IP6T_LOG_IPOPT) {
struct ip_auth_hdr _ahdr, *ah;
/* Max length: 3 "AH " */
@@ -158,7 +160,7 @@ static void dump_packet(const struct ip6t_log_info *info,
hdrlen = (hp->hdrlen+2)<<2;
break;
case IPPROTO_ESP:
if (info->logflags & IP6T_LOG_IPOPT) {
if (logflags & IP6T_LOG_IPOPT) {
struct ip_esp_hdr _esph, *eh;
/* Max length: 4 "ESP " */
@@ -190,7 +192,7 @@ static void dump_packet(const struct ip6t_log_info *info,
printk("Unknown Ext Hdr %u", currenthdr);
return;
}
if (info->logflags & IP6T_LOG_IPOPT)
if (logflags & IP6T_LOG_IPOPT)
printk(") ");
currenthdr = hp->nexthdr;
@@ -218,7 +220,7 @@ static void dump_packet(const struct ip6t_log_info *info,
printk("SPT=%u DPT=%u ",
ntohs(th->source), ntohs(th->dest));
/* Max length: 30 "SEQ=4294967295 ACK=4294967295 " */
if (info->logflags & IP6T_LOG_TCPSEQ)
if (logflags & IP6T_LOG_TCPSEQ)
printk("SEQ=%u ACK=%u ",
ntohl(th->seq), ntohl(th->ack_seq));
/* Max length: 13 "WINDOW=65535 " */
@@ -245,7 +247,7 @@ static void dump_packet(const struct ip6t_log_info *info,
/* Max length: 11 "URGP=65535 " */
printk("URGP=%u ", ntohs(th->urg_ptr));
if ((info->logflags & IP6T_LOG_TCPOPT)
if ((logflags & IP6T_LOG_TCPOPT)
&& th->doff * 4 > sizeof(struct tcphdr)) {
u_int8_t _opt[60 - sizeof(struct tcphdr)], *op;
unsigned int i;
@@ -349,7 +351,7 @@ static void dump_packet(const struct ip6t_log_info *info,
}
/* Max length: 15 "UID=4294967295 " */
if ((info->logflags & IP6T_LOG_UID) && recurse && skb->sk) {
if ((logflags & IP6T_LOG_UID) && recurse && skb->sk) {
read_lock_bh(&skb->sk->sk_callback_lock);
if (skb->sk->sk_socket && skb->sk->sk_socket->file)
printk("UID=%u ", skb->sk->sk_socket->file->f_uid);
@@ -357,19 +359,31 @@ static void dump_packet(const struct ip6t_log_info *info,
}
}
static struct nf_loginfo default_loginfo = {
.type = NF_LOG_TYPE_LOG,
.u = {
.log = {
.level = 0,
.logflags = NF_LOG_MASK,
},
},
};
static void
ip6t_log_packet(unsigned int hooknum,
ip6t_log_packet(unsigned int pf,
unsigned int hooknum,
const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const struct ip6t_log_info *loginfo,
const char *level_string,
const struct nf_loginfo *loginfo,
const char *prefix)
{
if (!loginfo)
loginfo = &default_loginfo;
spin_lock_bh(&log_lock);
printk(level_string);
printk("%sIN=%s OUT=%s ",
prefix == NULL ? loginfo->prefix : prefix,
printk("<%d>%sIN=%s OUT=%s ", loginfo->u.log.level,
prefix,
in ? in->name : "",
out ? out->name : "");
if (in && !out) {
@@ -416,29 +430,17 @@ ip6t_log_target(struct sk_buff **pskb,
void *userinfo)
{
const struct ip6t_log_info *loginfo = targinfo;
char level_string[4] = "< >";
struct nf_loginfo li;
level_string[1] = '0' + (loginfo->level % 8);
ip6t_log_packet(hooknum, *pskb, in, out, loginfo, level_string, NULL);
li.type = NF_LOG_TYPE_LOG;
li.u.log.level = loginfo->level;
li.u.log.logflags = loginfo->logflags;
nf_log_packet(PF_INET6, hooknum, *pskb, in, out, &li, loginfo->prefix);
return IP6T_CONTINUE;
}
static void
ip6t_logfn(unsigned int hooknum,
const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const char *prefix)
{
struct ip6t_log_info loginfo = {
.level = 0,
.logflags = IP6T_LOG_MASK,
.prefix = ""
};
ip6t_log_packet(hooknum, skb, in, out, &loginfo, KERN_WARNING, prefix);
}
static int ip6t_log_checkentry(const char *tablename,
const struct ip6t_entry *e,
@@ -475,20 +477,29 @@ static struct ip6t_target ip6t_log_reg = {
.me = THIS_MODULE,
};
static struct nf_logger ip6t_logger = {
.name = "ip6t_LOG",
.logfn = &ip6t_log_packet,
.me = THIS_MODULE,
};
static int __init init(void)
{
if (ip6t_register_target(&ip6t_log_reg))
return -EINVAL;
if (nflog)
nf_log_register(PF_INET6, &ip6t_logfn);
if (nf_log_register(PF_INET6, &ip6t_logger) < 0) {
printk(KERN_WARNING "ip6t_LOG: not logging via system console "
"since somebody else already registered for PF_INET6\n");
/* we cannot make module load fail here, since otherwise
* ip6tables userspace would abort */
}
return 0;
}
static void __exit fini(void)
{
if (nflog)
nf_log_unregister(PF_INET6, &ip6t_logfn);
nf_log_unregister_logger(&ip6t_logger);
ip6t_unregister_target(&ip6t_log_reg);
}