[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

@ -217,7 +217,7 @@ icmp_error(struct sk_buff *skb, enum ip_conntrack_info *ctinfo,
icmph = skb_header_pointer(skb, skb->nh.iph->ihl*4, sizeof(_ih), &_ih);
if (icmph == NULL) {
if (LOG_INVALID(IPPROTO_ICMP))
nf_log_packet(PF_INET, 0, skb, NULL, NULL,
nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
"ip_ct_icmp: short packet ");
return -NF_ACCEPT;
}
@ -231,13 +231,13 @@ icmp_error(struct sk_buff *skb, enum ip_conntrack_info *ctinfo,
if (!(u16)csum_fold(skb->csum))
break;
if (LOG_INVALID(IPPROTO_ICMP))
nf_log_packet(PF_INET, 0, skb, NULL, NULL,
nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
"ip_ct_icmp: bad HW ICMP checksum ");
return -NF_ACCEPT;
case CHECKSUM_NONE:
if ((u16)csum_fold(skb_checksum(skb, 0, skb->len, 0))) {
if (LOG_INVALID(IPPROTO_ICMP))
nf_log_packet(PF_INET, 0, skb, NULL, NULL,
nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
"ip_ct_icmp: bad ICMP checksum ");
return -NF_ACCEPT;
}
@ -254,7 +254,7 @@ checksum_skipped:
*/
if (icmph->type > NR_ICMP_TYPES) {
if (LOG_INVALID(IPPROTO_ICMP))
nf_log_packet(PF_INET, 0, skb, NULL, NULL,
nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
"ip_ct_icmp: invalid ICMP type ");
return -NF_ACCEPT;
}

View File

@ -716,7 +716,7 @@ static int tcp_in_window(struct ip_ct_tcp *state,
res = 1;
} else {
if (LOG_INVALID(IPPROTO_TCP))
nf_log_packet(PF_INET, 0, skb, NULL, NULL,
nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
"ip_ct_tcp: %s ",
before(seq, sender->td_maxend + 1) ?
after(end, sender->td_end - receiver->td_maxwin - 1) ?
@ -815,7 +815,7 @@ static int tcp_error(struct sk_buff *skb,
sizeof(_tcph), &_tcph);
if (th == NULL) {
if (LOG_INVALID(IPPROTO_TCP))
nf_log_packet(PF_INET, 0, skb, NULL, NULL,
nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
"ip_ct_tcp: short packet ");
return -NF_ACCEPT;
}
@ -823,7 +823,7 @@ static int tcp_error(struct sk_buff *skb,
/* Not whole TCP header or malformed packet */
if (th->doff*4 < sizeof(struct tcphdr) || tcplen < th->doff*4) {
if (LOG_INVALID(IPPROTO_TCP))
nf_log_packet(PF_INET, 0, skb, NULL, NULL,
nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
"ip_ct_tcp: truncated/malformed packet ");
return -NF_ACCEPT;
}
@ -840,7 +840,7 @@ static int tcp_error(struct sk_buff *skb,
skb->ip_summed == CHECKSUM_HW ? skb->csum
: skb_checksum(skb, iph->ihl*4, tcplen, 0))) {
if (LOG_INVALID(IPPROTO_TCP))
nf_log_packet(PF_INET, 0, skb, NULL, NULL,
nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
"ip_ct_tcp: bad TCP checksum ");
return -NF_ACCEPT;
}
@ -849,7 +849,7 @@ static int tcp_error(struct sk_buff *skb,
tcpflags = (((u_int8_t *)th)[13] & ~(TH_ECE|TH_CWR));
if (!tcp_valid_flags[tcpflags]) {
if (LOG_INVALID(IPPROTO_TCP))
nf_log_packet(PF_INET, 0, skb, NULL, NULL,
nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
"ip_ct_tcp: invalid TCP flag combination ");
return -NF_ACCEPT;
}
@ -897,8 +897,9 @@ static int tcp_packet(struct ip_conntrack *conntrack,
*/
write_unlock_bh(&tcp_lock);
if (LOG_INVALID(IPPROTO_TCP))
nf_log_packet(PF_INET, 0, skb, NULL, NULL,
"ip_ct_tcp: killing out of sync session ");
nf_log_packet(PF_INET, 0, skb, NULL, NULL,
NULL, "ip_ct_tcp: "
"killing out of sync session ");
if (del_timer(&conntrack->timeout))
conntrack->timeout.function((unsigned long)
conntrack);
@ -912,7 +913,7 @@ static int tcp_packet(struct ip_conntrack *conntrack,
write_unlock_bh(&tcp_lock);
if (LOG_INVALID(IPPROTO_TCP))
nf_log_packet(PF_INET, 0, skb, NULL, NULL,
nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
"ip_ct_tcp: invalid packet ignored ");
return NF_ACCEPT;
case TCP_CONNTRACK_MAX:
@ -922,7 +923,7 @@ static int tcp_packet(struct ip_conntrack *conntrack,
old_state);
write_unlock_bh(&tcp_lock);
if (LOG_INVALID(IPPROTO_TCP))
nf_log_packet(PF_INET, 0, skb, NULL, NULL,
nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
"ip_ct_tcp: invalid state ");
return -NF_ACCEPT;
case TCP_CONNTRACK_SYN_SENT:
@ -943,7 +944,7 @@ static int tcp_packet(struct ip_conntrack *conntrack,
write_unlock_bh(&tcp_lock);
if (LOG_INVALID(IPPROTO_TCP))
nf_log_packet(PF_INET, 0, skb, NULL, NULL,
"ip_ct_tcp: invalid SYN");
NULL, "ip_ct_tcp: invalid SYN");
return -NF_ACCEPT;
}
case TCP_CONNTRACK_CLOSE:

View File

@ -98,7 +98,7 @@ static int udp_error(struct sk_buff *skb, enum ip_conntrack_info *ctinfo,
hdr = skb_header_pointer(skb, iph->ihl*4, sizeof(_hdr), &_hdr);
if (hdr == NULL) {
if (LOG_INVALID(IPPROTO_UDP))
nf_log_packet(PF_INET, 0, skb, NULL, NULL,
nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
"ip_ct_udp: short packet ");
return -NF_ACCEPT;
}
@ -106,7 +106,7 @@ static int udp_error(struct sk_buff *skb, enum ip_conntrack_info *ctinfo,
/* Truncated/malformed packets */
if (ntohs(hdr->len) > udplen || ntohs(hdr->len) < sizeof(*hdr)) {
if (LOG_INVALID(IPPROTO_UDP))
nf_log_packet(PF_INET, 0, skb, NULL, NULL,
nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
"ip_ct_udp: truncated/malformed packet ");
return -NF_ACCEPT;
}
@ -126,7 +126,7 @@ static int udp_error(struct sk_buff *skb, enum ip_conntrack_info *ctinfo,
skb->ip_summed == CHECKSUM_HW ? skb->csum
: skb_checksum(skb, iph->ihl*4, udplen, 0))) {
if (LOG_INVALID(IPPROTO_UDP))
nf_log_packet(PF_INET, 0, skb, NULL, NULL,
nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
"ip_ct_udp: bad UDP checksum ");
return -NF_ACCEPT;
}

View File

@ -27,10 +27,6 @@ MODULE_LICENSE("GPL");
MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
MODULE_DESCRIPTION("iptables syslog logging module");
static unsigned int nflog = 1;
module_param(nflog, int, 0400);
MODULE_PARM_DESC(nflog, "register as internal netfilter logging module");
#if 0
#define DEBUGP printk
#else
@ -41,11 +37,17 @@ MODULE_PARM_DESC(nflog, "register as internal netfilter logging module");
static DEFINE_SPINLOCK(log_lock);
/* One level of recursion won't kill us */
static void dump_packet(const struct ipt_log_info *info,
static void dump_packet(const struct nf_loginfo *info,
const struct sk_buff *skb,
unsigned int iphoff)
{
struct iphdr _iph, *ih;
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, iphoff, sizeof(_iph), &_iph);
if (ih == NULL) {
@ -76,7 +78,7 @@ static void dump_packet(const struct ipt_log_info *info,
if (ntohs(ih->frag_off) & IP_OFFSET)
printk("FRAG:%u ", ntohs(ih->frag_off) & IP_OFFSET);
if ((info->logflags & IPT_LOG_IPOPT)
if ((logflags & IPT_LOG_IPOPT)
&& ih->ihl * 4 > sizeof(struct iphdr)) {
unsigned char _opt[4 * 15 - sizeof(struct iphdr)], *op;
unsigned int i, optsize;
@ -119,7 +121,7 @@ static void dump_packet(const struct ipt_log_info *info,
printk("SPT=%u DPT=%u ",
ntohs(th->source), ntohs(th->dest));
/* Max length: 30 "SEQ=4294967295 ACK=4294967295 " */
if (info->logflags & IPT_LOG_TCPSEQ)
if (logflags & IPT_LOG_TCPSEQ)
printk("SEQ=%u ACK=%u ",
ntohl(th->seq), ntohl(th->ack_seq));
/* Max length: 13 "WINDOW=65535 " */
@ -146,7 +148,7 @@ static void dump_packet(const struct ipt_log_info *info,
/* Max length: 11 "URGP=65535 " */
printk("URGP=%u ", ntohs(th->urg_ptr));
if ((info->logflags & IPT_LOG_TCPOPT)
if ((logflags & IPT_LOG_TCPOPT)
&& th->doff * 4 > sizeof(struct tcphdr)) {
unsigned char _opt[4 * 15 - sizeof(struct tcphdr)];
unsigned char *op;
@ -328,7 +330,7 @@ static void dump_packet(const struct ipt_log_info *info,
}
/* Max length: 15 "UID=4294967295 " */
if ((info->logflags & IPT_LOG_UID) && !iphoff && skb->sk) {
if ((logflags & IPT_LOG_UID) && !iphoff && 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);
@ -349,19 +351,31 @@ static void dump_packet(const struct ipt_log_info *info,
/* maxlen = 230+ 91 + 230 + 252 = 803 */
}
struct nf_loginfo default_loginfo = {
.type = NF_LOG_TYPE_LOG,
.u = {
.log = {
.level = 0,
.logflags = NF_LOG_MASK,
},
},
};
static void
ipt_log_packet(unsigned int hooknum,
ipt_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 ipt_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 : "");
#ifdef CONFIG_BRIDGE_NETFILTER
@ -405,30 +419,17 @@ ipt_log_target(struct sk_buff **pskb,
void *userinfo)
{
const struct ipt_log_info *loginfo = targinfo;
char level_string[4] = "< >";
struct nf_loginfo li;
level_string[1] = '0' + (loginfo->level % 8);
ipt_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_INET, hooknum, *pskb, in, out, &li, loginfo->prefix);
return IPT_CONTINUE;
}
static void
ipt_logfn(unsigned int hooknum,
const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const char *prefix)
{
struct ipt_log_info loginfo = {
.level = 0,
.logflags = IPT_LOG_MASK,
.prefix = ""
};
ipt_log_packet(hooknum, skb, in, out, &loginfo, KERN_WARNING, prefix);
}
static int ipt_log_checkentry(const char *tablename,
const struct ipt_entry *e,
void *targinfo,
@ -464,20 +465,29 @@ static struct ipt_target ipt_log_reg = {
.me = THIS_MODULE,
};
static struct nf_logger ipt_log_logger ={
.name = "ipt_LOG",
.logfn = &ipt_log_packet,
.me = THIS_MODULE,
};
static int __init init(void)
{
if (ipt_register_target(&ipt_log_reg))
return -EINVAL;
if (nflog)
nf_log_register(PF_INET, &ipt_logfn);
if (nf_log_register(PF_INET, &ipt_log_logger) < 0) {
printk(KERN_WARNING "ipt_LOG: not logging via system console "
"since somebody else already registered for PF_INET\n");
/* we cannot make module load fail here, since otherwise
* iptables userspace would abort */
}
return 0;
}
static void __exit fini(void)
{
if (nflog)
nf_log_unregister(PF_INET, &ipt_logfn);
nf_log_unregister_logger(&ipt_log_logger);
ipt_unregister_target(&ipt_log_reg);
}

View File

@ -304,18 +304,27 @@ static unsigned int ipt_ulog_target(struct sk_buff **pskb,
return IPT_CONTINUE;
}
static void ipt_logfn(unsigned int hooknum,
static void ipt_logfn(unsigned int pf,
unsigned int hooknum,
const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const struct nf_loginfo *li,
const char *prefix)
{
struct ipt_ulog_info loginfo = {
.nl_group = ULOG_DEFAULT_NLGROUP,
.copy_range = 0,
.qthreshold = ULOG_DEFAULT_QTHRESHOLD,
.prefix = ""
};
struct ipt_ulog_info loginfo;
if (!li || li->type != NF_LOG_TYPE_ULOG) {
loginfo.nl_group = ULOG_DEFAULT_NLGROUP;
loginfo.copy_range = 0;
loginfo.qthreshold = ULOG_DEFAULT_QTHRESHOLD;
loginfo.prefix[0] = '\0';
} else {
loginfo.nl_group = li->u.ulog.group;
loginfo.copy_range = li->u.ulog.copy_len;
loginfo.qthreshold = li->u.ulog.qthreshold;
strlcpy(loginfo.prefix, prefix, sizeof(loginfo.prefix));
}
ipt_ulog_packet(hooknum, skb, in, out, &loginfo, prefix);
}
@ -355,6 +364,12 @@ static struct ipt_target ipt_ulog_reg = {
.me = THIS_MODULE,
};
static struct nf_logger ipt_ulog_logger = {
.name = "ipt_ULOG",
.logfn = &ipt_logfn,
.me = THIS_MODULE,
};
static int __init init(void)
{
int i;
@ -382,7 +397,7 @@ static int __init init(void)
return -EINVAL;
}
if (nflog)
nf_log_register(PF_INET, &ipt_logfn);
nf_log_register(PF_INET, &ipt_ulog_logger);
return 0;
}
@ -395,7 +410,7 @@ static void __exit fini(void)
DEBUGP("ipt_ULOG: cleanup_module\n");
if (nflog)
nf_log_unregister(PF_INET, &ipt_logfn);
nf_log_unregister_logger(&ipt_ulog_logger);
ipt_unregister_target(&ipt_ulog_reg);
sock_release(nflognl->sk_socket);