/
ipt_SYSLOG.c
765 lines (648 loc) · 19.7 KB
/
ipt_SYSLOG.c
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/*
* This is a module which is used for logging packets.
*/
/* (C) 1999-2001 Paul `Rusty' Russell
* (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/skbuff.h>
#include <linux/ip.h>
#include <net/icmp.h>
#include <net/udp.h>
#include <net/tcp.h>
#include <net/route.h>
#include <net/sock.h>
#include <linux/un.h>
#include <linux/netfilter.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_ipv4/ipt_LOG.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Andras Elso <elso.andras@gmail.com>");
MODULE_DESCRIPTION("iptables syslog logging module");
static unsigned int loglist_maxlen __read_mostly = 1024;
module_param(loglist_maxlen, uint, 0600);
MODULE_PARM_DESC(loglist_maxlen, "loglist size");
static unsigned int reconnect_freq = 5000;
module_param(reconnect_freq, uint, 0600);
MODULE_PARM_DESC(reconnect_freq, "reconnect frequency if syslog offline");
struct logs {
char *data;
int counter;
struct list_head logs_list ;
} ;
/* Use lock to serialize, so printks don't overlap */
static DEFINE_SPINLOCK(log_lock);
static struct socket *sl_socket = NULL;
#define STAT_PROC_FS_NAME "ip_syslog_stat"
static LIST_HEAD(logs_list);
static unsigned int loglist_total = 0;
static unsigned int loglist_dropped = 0;
static int counter = 0;
static void syslog_work_fn(struct work_struct *work);
static DECLARE_WORK(syslog_work, syslog_work_fn);
static void syslog_timer(unsigned long dummy);
static DEFINE_TIMER(timer, syslog_timer, 0, 0);
static int syslog_connect(struct socket **socket);
static void syslog_close(struct socket **socket);
/* One level of recursion won't kill us */
static void dump_packet(const struct nf_loginfo *info,
const struct sk_buff *skb,
unsigned int iphoff,
char *buf, size_t buf_siz)
{
struct iphdr _iph;
const struct iphdr *ih;
unsigned int logflags;
size_t buf_len = strlen(buf);
#define BUF_ADD(ptr, siz, off, fmt...) \
do { \
off = strlen(ptr); \
snprintf(((ptr)+(off)), ((siz) > (off) ? (siz)-(off) : 0), ##fmt); \
} while (0)
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) {
BUF_ADD(buf,buf_siz,buf_len, "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 " */
BUF_ADD(buf,buf_siz,buf_len, "SRC=%u.%u.%u.%u DST=%u.%u.%u.%u ",
NIPQUAD(ih->saddr), NIPQUAD(ih->daddr));
/* Max length: 46 "LEN=65535 TOS=0xFF PREC=0xFF TTL=255 ID=65535 " */
BUF_ADD(buf,buf_siz,buf_len, "LEN=%u TOS=0x%02X PREC=0x%02X TTL=%u ID=%u ",
ntohs(ih->tot_len), 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)
BUF_ADD(buf,buf_siz,buf_len, "CE ");
if (ntohs(ih->frag_off) & IP_DF)
BUF_ADD(buf,buf_siz,buf_len, "DF ");
if (ntohs(ih->frag_off) & IP_MF)
BUF_ADD(buf,buf_siz,buf_len, "MF ");
/* Max length: 11 "FRAG:65535 " */
if (ntohs(ih->frag_off) & IP_OFFSET)
BUF_ADD(buf,buf_siz,buf_len, "FRAG:%u ", ntohs(ih->frag_off) & IP_OFFSET);
if ((logflags & IPT_LOG_IPOPT)
&& ih->ihl * 4 > sizeof(struct iphdr)) {
unsigned char _opt[4 * 15 - sizeof(struct iphdr)], *op;
unsigned int i, optsize;
optsize = ih->ihl * 4 - sizeof(struct iphdr);
op = skb_header_pointer(skb, iphoff+sizeof(_iph),
optsize, _opt);
if (op == NULL) {
BUF_ADD(buf,buf_siz,buf_len, "TRUNCATED");
return;
}
/* Max length: 127 "OPT (" 15*4*2chars ") " */
BUF_ADD(buf,buf_siz,buf_len, "OPT (");
for (i = 0; i < optsize; i++)
BUF_ADD(buf,buf_siz,buf_len, "%02X", op[i]);
BUF_ADD(buf,buf_siz,buf_len, ") ");
}
switch (ih->protocol) {
case IPPROTO_TCP: {
struct tcphdr _tcph;
const struct tcphdr *th;
/* Max length: 10 "PROTO=TCP " */
BUF_ADD(buf,buf_siz,buf_len, "PROTO=TCP ");
if (ntohs(ih->frag_off) & IP_OFFSET)
break;
/* Max length: 25 "INCOMPLETE [65535 bytes] " */
th = skb_header_pointer(skb, iphoff + ih->ihl * 4,
sizeof(_tcph), &_tcph);
if (th == NULL) {
BUF_ADD(buf,buf_siz,buf_len, "INCOMPLETE [%u bytes] ",
skb->len - iphoff - ih->ihl*4);
break;
}
/* Max length: 20 "SPT=65535 DPT=65535 " */
BUF_ADD(buf,buf_siz,buf_len, "SPT=%u DPT=%u ",
ntohs(th->source), ntohs(th->dest));
/* Max length: 30 "SEQ=4294967295 ACK=4294967295 " */
if (logflags & IPT_LOG_TCPSEQ)
BUF_ADD(buf,buf_siz,buf_len, "SEQ=%u ACK=%u ",
ntohl(th->seq), ntohl(th->ack_seq));
/* Max length: 13 "WINDOW=65535 " */
BUF_ADD(buf,buf_siz,buf_len, "WINDOW=%u ", ntohs(th->window));
/* Max length: 9 "RES=0x3F " */
BUF_ADD(buf,buf_siz,buf_len, "RES=0x%02x ", (u8)(ntohl(tcp_flag_word(th) & TCP_RESERVED_BITS) >> 22));
/* Max length: 32 "CWR ECE URG ACK PSH RST SYN FIN " */
if (th->cwr)
BUF_ADD(buf,buf_siz,buf_len, "CWR ");
if (th->ece)
BUF_ADD(buf,buf_siz,buf_len, "ECE ");
if (th->urg)
BUF_ADD(buf,buf_siz,buf_len, "URG ");
if (th->ack)
BUF_ADD(buf,buf_siz,buf_len, "ACK ");
if (th->psh)
BUF_ADD(buf,buf_siz,buf_len, "PSH ");
if (th->rst)
BUF_ADD(buf,buf_siz,buf_len, "RST ");
if (th->syn)
BUF_ADD(buf,buf_siz,buf_len, "SYN ");
if (th->fin)
BUF_ADD(buf,buf_siz,buf_len, "FIN ");
/* Max length: 11 "URGP=65535 " */
BUF_ADD(buf,buf_siz,buf_len, "URGP=%u ", ntohs(th->urg_ptr));
if ((logflags & IPT_LOG_TCPOPT)
&& th->doff * 4 > sizeof(struct tcphdr)) {
unsigned char _opt[4 * 15 - sizeof(struct tcphdr)];
const unsigned char *op;
unsigned int i, optsize;
optsize = th->doff * 4 - sizeof(struct tcphdr);
op = skb_header_pointer(skb,
iphoff+ih->ihl*4+sizeof(_tcph),
optsize, _opt);
if (op == NULL) {
BUF_ADD(buf,buf_siz,buf_len, "TRUNCATED");
return;
}
/* Max length: 127 "OPT (" 15*4*2chars ") " */
BUF_ADD(buf,buf_siz,buf_len, "OPT (");
for (i = 0; i < optsize; i++)
BUF_ADD(buf,buf_siz,buf_len, "%02X", op[i]);
BUF_ADD(buf,buf_siz,buf_len, ") ");
}
break;
}
case IPPROTO_UDP:
case IPPROTO_UDPLITE: {
struct udphdr _udph;
const struct udphdr *uh;
if (ih->protocol == IPPROTO_UDP)
/* Max length: 10 "PROTO=UDP " */
BUF_ADD(buf,buf_siz,buf_len, "PROTO=UDP " );
else /* Max length: 14 "PROTO=UDPLITE " */
BUF_ADD(buf,buf_siz,buf_len, "PROTO=UDPLITE ");
if (ntohs(ih->frag_off) & IP_OFFSET)
break;
/* Max length: 25 "INCOMPLETE [65535 bytes] " */
uh = skb_header_pointer(skb, iphoff+ih->ihl*4,
sizeof(_udph), &_udph);
if (uh == NULL) {
BUF_ADD(buf,buf_siz,buf_len, "INCOMPLETE [%u bytes] ",
skb->len - iphoff - ih->ihl*4);
break;
}
/* Max length: 20 "SPT=65535 DPT=65535 " */
BUF_ADD(buf,buf_siz,buf_len, "SPT=%u DPT=%u LEN=%u ",
ntohs(uh->source), ntohs(uh->dest),
ntohs(uh->len));
break;
}
case IPPROTO_ICMP: {
struct icmphdr _icmph;
const struct icmphdr *ich;
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 };
/* Max length: 11 "PROTO=ICMP " */
BUF_ADD(buf,buf_siz,buf_len, "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 == NULL) {
BUF_ADD(buf,buf_siz,buf_len, "INCOMPLETE [%u bytes] ",
skb->len - iphoff - ih->ihl*4);
break;
}
/* Max length: 18 "TYPE=255 CODE=255 " */
BUF_ADD(buf,buf_siz,buf_len, "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]) {
BUF_ADD(buf,buf_siz,buf_len, "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 " */
BUF_ADD(buf,buf_siz,buf_len, "ID=%u SEQ=%u ",
ntohs(ich->un.echo.id),
ntohs(ich->un.echo.sequence));
break;
case ICMP_PARAMETERPROB:
/* Max length: 14 "PARAMETER=255 " */
BUF_ADD(buf,buf_siz,buf_len, "PARAMETER=%u ",
ntohl(ich->un.gateway) >> 24);
break;
case ICMP_REDIRECT:
/* Max length: 24 "GATEWAY=255.255.255.255 " */
BUF_ADD(buf,buf_siz,buf_len, "GATEWAY=%u.%u.%u.%u ",
NIPQUAD(ich->un.gateway));
/* Fall through */
case ICMP_DEST_UNREACH:
case ICMP_SOURCE_QUENCH:
case ICMP_TIME_EXCEEDED:
/* Max length: 3+maxlen */
if (!iphoff) { /* Only recurse once. */
BUF_ADD(buf,buf_siz,buf_len, "[");
dump_packet(info, skb,
iphoff + ih->ihl*4+sizeof(_icmph), buf, buf_siz);
BUF_ADD(buf,buf_siz,buf_len, "] ");
}
/* Max length: 10 "MTU=65535 " */
if (ich->type == ICMP_DEST_UNREACH
&& ich->code == ICMP_FRAG_NEEDED)
BUF_ADD(buf,buf_siz,buf_len, "MTU=%u ", ntohs(ich->un.frag.mtu));
}
break;
}
/* Max Length */
case IPPROTO_AH: {
struct ip_auth_hdr _ahdr;
const struct ip_auth_hdr *ah;
if (ntohs(ih->frag_off) & IP_OFFSET)
break;
/* Max length: 9 "PROTO=AH " */
BUF_ADD(buf,buf_siz,buf_len, "PROTO=AH ");
/* Max length: 25 "INCOMPLETE [65535 bytes] " */
ah = skb_header_pointer(skb, iphoff+ih->ihl*4,
sizeof(_ahdr), &_ahdr);
if (ah == NULL) {
BUF_ADD(buf,buf_siz,buf_len, "INCOMPLETE [%u bytes] ",
skb->len - iphoff - ih->ihl*4);
break;
}
/* Length: 15 "SPI=0xF1234567 " */
BUF_ADD(buf,buf_siz,buf_len, "SPI=0x%x ", ntohl(ah->spi));
break;
}
case IPPROTO_ESP: {
struct ip_esp_hdr _esph;
const struct ip_esp_hdr *eh;
/* Max length: 10 "PROTO=ESP " */
BUF_ADD(buf,buf_siz,buf_len, "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 == NULL) {
BUF_ADD(buf,buf_siz,buf_len, "INCOMPLETE [%u bytes] ",
skb->len - iphoff - ih->ihl*4);
break;
}
/* Length: 15 "SPI=0xF1234567 " */
BUF_ADD(buf,buf_siz,buf_len, "SPI=0x%x ", ntohl(eh->spi));
break;
}
/* Max length: 10 "PROTO 255 " */
default:
BUF_ADD(buf,buf_siz,buf_len, "PROTO=%u ", ih->protocol);
}
/* Max length: 15 "UID=4294967295 " */
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)
BUF_ADD(buf,buf_siz,buf_len, "UID=%u ", skb->sk->sk_socket->file->f_uid);
read_unlock_bh(&skb->sk->sk_callback_lock);
}
/* 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 struct nf_loginfo default_loginfo = {
.type = NF_LOG_TYPE_LOG,
.u = {
.log = {
.level = 0,
.logflags = NF_LOG_MASK,
},
},
};
static void syslog_timer(unsigned long dummy)
{
printk(KERN_DEBUG "ip_syslog: syslog_timer\n");
schedule_work(&syslog_work);
}
static void syslog_work_fn(struct work_struct *work)
{
struct msghdr msg;
struct kvec iov;
int ret;
size_t n = 0;
struct logs * log_entry;
if (sl_socket != NULL)
goto cont;
ret = syslog_connect(&sl_socket);
if (ret >= 0)
goto cont;
if (!timer_pending(&timer))
{
timer.expires = jiffies + msecs_to_jiffies(reconnect_freq);
add_timer(&timer);
}
return ;
cont:
if (list_empty(&logs_list))
return;
spin_lock_irq(&log_lock);
while (!list_empty(&logs_list))
{
log_entry = list_first_entry(&logs_list, struct logs, logs_list);
printk(KERN_DEBUG "ip_syslog: work data (%d): %d\n", counter, log_entry->counter);
n = strlen(log_entry->data);
iov.iov_base = (void *)log_entry->data;
iov.iov_len = n;
msg.msg_name = NULL;
msg.msg_namelen = 0;
msg.msg_iov = (struct iovec *)&iov;
msg.msg_iovlen = 1;
msg.msg_control = NULL;
msg.msg_controllen = 0;
msg.msg_namelen = 0;
msg.msg_flags = MSG_DONTWAIT|MSG_NOSIGNAL;
ret = kernel_sendmsg(sl_socket, &msg, &iov, 1, n);
if (ret < 0)
{
printk("ip_syslog: kernel_sendmsg error:%d\n", ret);
if (ret == -EPIPE)
{
syslog_close(&sl_socket);
schedule_work(&syslog_work);
}
break;
}
loglist_total--;
list_del(&log_entry->logs_list);
kfree(log_entry->data);
kfree(log_entry);
}
spin_unlock_irq(&log_lock);
return ;
}
static void
send_data(const char *buffer, const size_t length)
{
struct logs *newlog;
if (loglist_total >= loglist_maxlen) {
struct logs * log_entry;
loglist_dropped++;
printk(KERN_WARNING "ip_SYSLOG: full at %d entries, dropping log. Dropped: %d\n", loglist_total, loglist_dropped);
log_entry = list_first_entry(&logs_list, struct logs, logs_list);
loglist_total--;
list_del(&log_entry->logs_list);
kfree(log_entry->data);
kfree(log_entry);
}
newlog = kzalloc(sizeof(struct logs), GFP_KERNEL);
counter++;
newlog->data = kstrdup(buffer, GFP_KERNEL);
newlog->counter = counter;
loglist_total++;
list_add_tail(&newlog->logs_list, &logs_list);
schedule_work(&syslog_work);
printk(KERN_DEBUG "send_data: %d\n", counter);
}
static void
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 nf_loginfo *loginfo,
const char *prefix)
{
static char buf[4096];
size_t buf_siz = sizeof(buf);
size_t buf_len = 0;
*buf = '\0';
if (!loginfo)
loginfo = &default_loginfo;
spin_lock_bh(&log_lock);
BUF_ADD(buf,buf_siz,buf_len, "<%d>%sIN=%s OUT=%s ", loginfo->u.log.level,
prefix[0] ? prefix : "netfilter: ",
in ? in->name : "",
out ? out->name : "");
#ifdef CONFIG_BRIDGE_NETFILTER
if (skb->nf_bridge) {
const struct net_device *physindev;
const struct net_device *physoutdev;
physindev = skb->nf_bridge->physindev;
if (physindev && in != physindev)
BUF_ADD(buf,buf_siz,buf_len, "PHYSIN=%s ", physindev->name);
physoutdev = skb->nf_bridge->physoutdev;
if (physoutdev && out != physoutdev)
BUF_ADD(buf,buf_siz,buf_len, "PHYSOUT=%s ", physoutdev->name);
}
#endif
if (in && !out) {
/* MAC logging for input chain only. */
BUF_ADD(buf,buf_siz,buf_len, "MAC=");
if (skb->dev && skb->dev->hard_header_len
&& skb->mac_header != skb->network_header) {
int i;
const unsigned char *p = skb_mac_header(skb);
for (i = 0; i < skb->dev->hard_header_len; i++,p++)
BUF_ADD(buf,buf_siz,buf_len, "%02x%c", *p,
i==skb->dev->hard_header_len - 1
? ' ':':');
} else
BUF_ADD(buf,buf_siz,buf_len, " ");
}
dump_packet(loginfo, skb, 0, buf, buf_siz);
BUF_ADD(buf,buf_siz,buf_len, "\n");
send_data(buf, strlen(buf));
spin_unlock_bh(&log_lock);
}
static unsigned int
ipt_log_target(struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
unsigned int hooknum,
const struct xt_target *target,
const void *targinfo)
{
const struct ipt_log_info *loginfo = targinfo;
struct nf_loginfo li;
li.type = NF_LOG_TYPE_LOG;
li.u.log.level = loginfo->level;
li.u.log.logflags = loginfo->logflags;
ipt_log_packet(PF_INET, hooknum, skb, in, out, &li,
loginfo->prefix);
return XT_CONTINUE;
}
static bool ipt_log_checkentry(const char *tablename,
const void *e,
const struct xt_target *target,
void *targinfo,
unsigned int hook_mask)
{
const struct ipt_log_info *loginfo = targinfo;
if (loginfo->level >= 8) {
pr_debug("SYSLOG: level %u >= 8\n", loginfo->level);
return false;
}
if (loginfo->prefix[sizeof(loginfo->prefix)-1] != '\0') {
pr_debug("SYSLOG: prefix term %i\n",
loginfo->prefix[sizeof(loginfo->prefix)-1]);
return false;
}
return true;
}
static struct xt_target ipt_log_reg __read_mostly = {
.name = "SYSLOG",
.family = AF_INET,
.target = ipt_log_target,
.targetsize = sizeof(struct ipt_log_info),
.checkentry = ipt_log_checkentry,
.me = THIS_MODULE,
};
static struct nf_logger ipt_log_logger ={
.name = "ipt_SYSLOG",
.logfn = &ipt_log_packet,
.me = THIS_MODULE,
};
static int ip_syslogstat_show(struct seq_file *m, void *v)
{
spin_lock_bh(&log_lock);
seq_printf(m,
"Counter : %u\n"
"Queue length : %u\n"
"Queue max. length : %u\n"
"Queue dropped : %u\n",
counter,
loglist_total,
loglist_maxlen,
loglist_dropped);
spin_unlock_bh(&log_lock);
return 0;
}
static int ip_syslogstat_open(struct inode *inode, struct file *file)
{
return single_open(file, ip_syslogstat_show, NULL);
}
static const struct file_operations ip_syslogstat_proc_fops = {
.open = ip_syslogstat_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
.owner = THIS_MODULE,
};
static int syslog_connect(struct socket **socket)
{
int ret = 0;
int retry = 0;
int logtype = SOCK_DGRAM;
struct sockaddr_un syslog_server;
while (retry < 2)
{
ret = sock_create_kern(PF_UNIX, logtype, 0, socket);
if (ret < 0)
break;
syslog_server.sun_family = PF_UNIX;
strcpy(syslog_server.sun_path , "/dev/log");
ret = kernel_connect(*socket, (struct sockaddr *)&syslog_server, sizeof(struct sockaddr_un) - 1, 0);
if (ret < 0)
{
if (ret == -EPROTOTYPE)
{
logtype = (logtype == SOCK_DGRAM ? SOCK_STREAM : SOCK_DGRAM);
}
retry++;
goto cleanup_sock;
}
(*socket)->sk->sk_allocation = GFP_NOIO;
return ret;
cleanup_sock:
sock_release(*socket);
*socket = NULL;
}
return ret;
}
static void syslog_close(struct socket **socket)
{
if (!*socket) return;
kernel_sock_shutdown(*socket, SHUT_RDWR);
sock_release(*socket);
*socket = NULL;
}
static int __init ipt_log_init(void)
{
int ret;
struct proc_dir_entry *proc;
ret = xt_register_target(&ipt_log_reg);
if (ret < 0)
return ret;
proc = create_proc_entry(STAT_PROC_FS_NAME, 0, init_net.proc_net);
if (proc) {
proc->owner = THIS_MODULE;
proc->proc_fops = &ip_syslogstat_proc_fops;
} else {
printk(KERN_ERR "ip_SYSLOG: failed to create proc entry\n");
goto cleanup_target;
}
ret = syslog_connect(&sl_socket);
if (ret < 0)
{
if (ret == -ECONNREFUSED)
{
timer.expires = jiffies + msecs_to_jiffies(reconnect_freq);
add_timer(&timer);
}
else
goto cleanup_proc;
}
nf_log_register(PF_INET, &ipt_log_logger);
return 0;
cleanup_proc:
proc_net_remove(&init_net, STAT_PROC_FS_NAME);
cleanup_target:
xt_unregister_target(&ipt_log_reg);
return ret;
}
static void __exit ipt_log_fini(void)
{
nf_log_unregister(&ipt_log_logger);
/* remove timer, if it is pending */
if (timer_pending(&timer))
del_timer(&timer);
flush_scheduled_work();
syslog_close(&sl_socket);
if (loglist_total > 0)
printk(KERN_WARNING "ip_SYSLOG: dropping %d log(s). Dropped: %d\n", loglist_total, loglist_dropped + loglist_total);
proc_net_remove(&init_net, STAT_PROC_FS_NAME);
xt_unregister_target(&ipt_log_reg);
}
module_init(ipt_log_init);
module_exit(ipt_log_fini);