[NETFILTER]: {ip, nf}_conntrack_sctp: fix remotely triggerable NULL ptr dereference...
[linux-2.6] / net / netfilter / nf_conntrack_standalone.c
1 /* (C) 1999-2001 Paul `Rusty' Russell
2  * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8
9 #include <linux/types.h>
10 #include <linux/netfilter.h>
11 #include <linux/module.h>
12 #include <linux/skbuff.h>
13 #include <linux/proc_fs.h>
14 #include <linux/seq_file.h>
15 #include <linux/percpu.h>
16 #include <linux/netdevice.h>
17 #ifdef CONFIG_SYSCTL
18 #include <linux/sysctl.h>
19 #endif
20
21 #include <net/netfilter/nf_conntrack.h>
22 #include <net/netfilter/nf_conntrack_core.h>
23 #include <net/netfilter/nf_conntrack_l3proto.h>
24 #include <net/netfilter/nf_conntrack_l4proto.h>
25 #include <net/netfilter/nf_conntrack_expect.h>
26 #include <net/netfilter/nf_conntrack_helper.h>
27
28 MODULE_LICENSE("GPL");
29
30 #ifdef CONFIG_PROC_FS
31 int
32 print_tuple(struct seq_file *s, const struct nf_conntrack_tuple *tuple,
33             struct nf_conntrack_l3proto *l3proto,
34             struct nf_conntrack_l4proto *l4proto)
35 {
36         return l3proto->print_tuple(s, tuple) || l4proto->print_tuple(s, tuple);
37 }
38 EXPORT_SYMBOL_GPL(print_tuple);
39
40 #ifdef CONFIG_NF_CT_ACCT
41 static unsigned int
42 seq_print_counters(struct seq_file *s,
43                    const struct ip_conntrack_counter *counter)
44 {
45         return seq_printf(s, "packets=%llu bytes=%llu ",
46                           (unsigned long long)counter->packets,
47                           (unsigned long long)counter->bytes);
48 }
49 #else
50 #define seq_print_counters(x, y)        0
51 #endif
52
53 struct ct_iter_state {
54         unsigned int bucket;
55 };
56
57 static struct hlist_node *ct_get_first(struct seq_file *seq)
58 {
59         struct ct_iter_state *st = seq->private;
60
61         for (st->bucket = 0;
62              st->bucket < nf_conntrack_htable_size;
63              st->bucket++) {
64                 if (!hlist_empty(&nf_conntrack_hash[st->bucket]))
65                         return nf_conntrack_hash[st->bucket].first;
66         }
67         return NULL;
68 }
69
70 static struct hlist_node *ct_get_next(struct seq_file *seq,
71                                       struct hlist_node *head)
72 {
73         struct ct_iter_state *st = seq->private;
74
75         head = head->next;
76         while (head == NULL) {
77                 if (++st->bucket >= nf_conntrack_htable_size)
78                         return NULL;
79                 head = nf_conntrack_hash[st->bucket].first;
80         }
81         return head;
82 }
83
84 static struct hlist_node *ct_get_idx(struct seq_file *seq, loff_t pos)
85 {
86         struct hlist_node *head = ct_get_first(seq);
87
88         if (head)
89                 while (pos && (head = ct_get_next(seq, head)))
90                         pos--;
91         return pos ? NULL : head;
92 }
93
94 static void *ct_seq_start(struct seq_file *seq, loff_t *pos)
95 {
96         read_lock_bh(&nf_conntrack_lock);
97         return ct_get_idx(seq, *pos);
98 }
99
100 static void *ct_seq_next(struct seq_file *s, void *v, loff_t *pos)
101 {
102         (*pos)++;
103         return ct_get_next(s, v);
104 }
105
106 static void ct_seq_stop(struct seq_file *s, void *v)
107 {
108         read_unlock_bh(&nf_conntrack_lock);
109 }
110
111 /* return 0 on success, 1 in case of error */
112 static int ct_seq_show(struct seq_file *s, void *v)
113 {
114         const struct nf_conntrack_tuple_hash *hash = v;
115         const struct nf_conn *conntrack = nf_ct_tuplehash_to_ctrack(hash);
116         struct nf_conntrack_l3proto *l3proto;
117         struct nf_conntrack_l4proto *l4proto;
118
119         NF_CT_ASSERT(conntrack);
120
121         /* we only want to print DIR_ORIGINAL */
122         if (NF_CT_DIRECTION(hash))
123                 return 0;
124
125         l3proto = __nf_ct_l3proto_find(conntrack->tuplehash[IP_CT_DIR_ORIGINAL]
126                                        .tuple.src.l3num);
127
128         NF_CT_ASSERT(l3proto);
129         l4proto = __nf_ct_l4proto_find(conntrack->tuplehash[IP_CT_DIR_ORIGINAL]
130                                    .tuple.src.l3num,
131                                    conntrack->tuplehash[IP_CT_DIR_ORIGINAL]
132                                    .tuple.dst.protonum);
133         NF_CT_ASSERT(l4proto);
134
135         if (seq_printf(s, "%-8s %u %-8s %u %ld ",
136                        l3proto->name,
137                        conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num,
138                        l4proto->name,
139                        conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum,
140                        timer_pending(&conntrack->timeout)
141                        ? (long)(conntrack->timeout.expires - jiffies)/HZ : 0) != 0)
142                 return -ENOSPC;
143
144         if (l3proto->print_conntrack(s, conntrack))
145                 return -ENOSPC;
146
147         if (l4proto->print_conntrack(s, conntrack))
148                 return -ENOSPC;
149
150         if (print_tuple(s, &conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
151                         l3proto, l4proto))
152                 return -ENOSPC;
153
154         if (seq_print_counters(s, &conntrack->counters[IP_CT_DIR_ORIGINAL]))
155                 return -ENOSPC;
156
157         if (!(test_bit(IPS_SEEN_REPLY_BIT, &conntrack->status)))
158                 if (seq_printf(s, "[UNREPLIED] "))
159                         return -ENOSPC;
160
161         if (print_tuple(s, &conntrack->tuplehash[IP_CT_DIR_REPLY].tuple,
162                         l3proto, l4proto))
163                 return -ENOSPC;
164
165         if (seq_print_counters(s, &conntrack->counters[IP_CT_DIR_REPLY]))
166                 return -ENOSPC;
167
168         if (test_bit(IPS_ASSURED_BIT, &conntrack->status))
169                 if (seq_printf(s, "[ASSURED] "))
170                         return -ENOSPC;
171
172 #if defined(CONFIG_NF_CONNTRACK_MARK)
173         if (seq_printf(s, "mark=%u ", conntrack->mark))
174                 return -ENOSPC;
175 #endif
176
177 #ifdef CONFIG_NF_CONNTRACK_SECMARK
178         if (seq_printf(s, "secmark=%u ", conntrack->secmark))
179                 return -ENOSPC;
180 #endif
181
182         if (seq_printf(s, "use=%u\n", atomic_read(&conntrack->ct_general.use)))
183                 return -ENOSPC;
184         
185         return 0;
186 }
187
188 static const struct seq_operations ct_seq_ops = {
189         .start = ct_seq_start,
190         .next  = ct_seq_next,
191         .stop  = ct_seq_stop,
192         .show  = ct_seq_show
193 };
194
195 static int ct_open(struct inode *inode, struct file *file)
196 {
197         struct seq_file *seq;
198         struct ct_iter_state *st;
199         int ret;
200
201         st = kmalloc(sizeof(struct ct_iter_state), GFP_KERNEL);
202         if (st == NULL)
203                 return -ENOMEM;
204         ret = seq_open(file, &ct_seq_ops);
205         if (ret)
206                 goto out_free;
207         seq          = file->private_data;
208         seq->private = st;
209         memset(st, 0, sizeof(struct ct_iter_state));
210         return ret;
211 out_free:
212         kfree(st);
213         return ret;
214 }
215
216 static const struct file_operations ct_file_ops = {
217         .owner   = THIS_MODULE,
218         .open    = ct_open,
219         .read    = seq_read,
220         .llseek  = seq_lseek,
221         .release = seq_release_private,
222 };
223
224 static void *ct_cpu_seq_start(struct seq_file *seq, loff_t *pos)
225 {
226         int cpu;
227
228         if (*pos == 0)
229                 return SEQ_START_TOKEN;
230
231         for (cpu = *pos-1; cpu < NR_CPUS; ++cpu) {
232                 if (!cpu_possible(cpu))
233                         continue;
234                 *pos = cpu + 1;
235                 return &per_cpu(nf_conntrack_stat, cpu);
236         }
237
238         return NULL;
239 }
240
241 static void *ct_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos)
242 {
243         int cpu;
244
245         for (cpu = *pos; cpu < NR_CPUS; ++cpu) {
246                 if (!cpu_possible(cpu))
247                         continue;
248                 *pos = cpu + 1;
249                 return &per_cpu(nf_conntrack_stat, cpu);
250         }
251
252         return NULL;
253 }
254
255 static void ct_cpu_seq_stop(struct seq_file *seq, void *v)
256 {
257 }
258
259 static int ct_cpu_seq_show(struct seq_file *seq, void *v)
260 {
261         unsigned int nr_conntracks = atomic_read(&nf_conntrack_count);
262         struct ip_conntrack_stat *st = v;
263
264         if (v == SEQ_START_TOKEN) {
265                 seq_printf(seq, "entries  searched found new invalid ignore delete delete_list insert insert_failed drop early_drop icmp_error  expect_new expect_create expect_delete\n");
266                 return 0;
267         }
268
269         seq_printf(seq, "%08x  %08x %08x %08x %08x %08x %08x %08x "
270                         "%08x %08x %08x %08x %08x  %08x %08x %08x \n",
271                    nr_conntracks,
272                    st->searched,
273                    st->found,
274                    st->new,
275                    st->invalid,
276                    st->ignore,
277                    st->delete,
278                    st->delete_list,
279                    st->insert,
280                    st->insert_failed,
281                    st->drop,
282                    st->early_drop,
283                    st->error,
284
285                    st->expect_new,
286                    st->expect_create,
287                    st->expect_delete
288                 );
289         return 0;
290 }
291
292 static const struct seq_operations ct_cpu_seq_ops = {
293         .start  = ct_cpu_seq_start,
294         .next   = ct_cpu_seq_next,
295         .stop   = ct_cpu_seq_stop,
296         .show   = ct_cpu_seq_show,
297 };
298
299 static int ct_cpu_seq_open(struct inode *inode, struct file *file)
300 {
301         return seq_open(file, &ct_cpu_seq_ops);
302 }
303
304 static const struct file_operations ct_cpu_seq_fops = {
305         .owner   = THIS_MODULE,
306         .open    = ct_cpu_seq_open,
307         .read    = seq_read,
308         .llseek  = seq_lseek,
309         .release = seq_release_private,
310 };
311 #endif /* CONFIG_PROC_FS */
312
313 /* Sysctl support */
314
315 int nf_conntrack_checksum __read_mostly = 1;
316 EXPORT_SYMBOL_GPL(nf_conntrack_checksum);
317
318 #ifdef CONFIG_SYSCTL
319 /* Log invalid packets of a given protocol */
320 static int log_invalid_proto_min = 0;
321 static int log_invalid_proto_max = 255;
322
323 static struct ctl_table_header *nf_ct_sysctl_header;
324
325 static ctl_table nf_ct_sysctl_table[] = {
326         {
327                 .ctl_name       = NET_NF_CONNTRACK_MAX,
328                 .procname       = "nf_conntrack_max",
329                 .data           = &nf_conntrack_max,
330                 .maxlen         = sizeof(int),
331                 .mode           = 0644,
332                 .proc_handler   = &proc_dointvec,
333         },
334         {
335                 .ctl_name       = NET_NF_CONNTRACK_COUNT,
336                 .procname       = "nf_conntrack_count",
337                 .data           = &nf_conntrack_count,
338                 .maxlen         = sizeof(int),
339                 .mode           = 0444,
340                 .proc_handler   = &proc_dointvec,
341         },
342         {
343                 .ctl_name       = NET_NF_CONNTRACK_BUCKETS,
344                 .procname       = "nf_conntrack_buckets",
345                 .data           = &nf_conntrack_htable_size,
346                 .maxlen         = sizeof(unsigned int),
347                 .mode           = 0444,
348                 .proc_handler   = &proc_dointvec,
349         },
350         {
351                 .ctl_name       = NET_NF_CONNTRACK_CHECKSUM,
352                 .procname       = "nf_conntrack_checksum",
353                 .data           = &nf_conntrack_checksum,
354                 .maxlen         = sizeof(unsigned int),
355                 .mode           = 0644,
356                 .proc_handler   = &proc_dointvec,
357         },
358         {
359                 .ctl_name       = NET_NF_CONNTRACK_LOG_INVALID,
360                 .procname       = "nf_conntrack_log_invalid",
361                 .data           = &nf_ct_log_invalid,
362                 .maxlen         = sizeof(unsigned int),
363                 .mode           = 0644,
364                 .proc_handler   = &proc_dointvec_minmax,
365                 .strategy       = &sysctl_intvec,
366                 .extra1         = &log_invalid_proto_min,
367                 .extra2         = &log_invalid_proto_max,
368         },
369         {
370                 .ctl_name       = CTL_UNNUMBERED,
371                 .procname       = "nf_conntrack_expect_max",
372                 .data           = &nf_ct_expect_max,
373                 .maxlen         = sizeof(int),
374                 .mode           = 0644,
375                 .proc_handler   = &proc_dointvec,
376         },
377         { .ctl_name = 0 }
378 };
379
380 #define NET_NF_CONNTRACK_MAX 2089
381
382 static ctl_table nf_ct_netfilter_table[] = {
383         {
384                 .ctl_name       = NET_NETFILTER,
385                 .procname       = "netfilter",
386                 .mode           = 0555,
387                 .child          = nf_ct_sysctl_table,
388         },
389         {
390                 .ctl_name       = NET_NF_CONNTRACK_MAX,
391                 .procname       = "nf_conntrack_max",
392                 .data           = &nf_conntrack_max,
393                 .maxlen         = sizeof(int),
394                 .mode           = 0644,
395                 .proc_handler   = &proc_dointvec,
396         },
397         { .ctl_name = 0 }
398 };
399
400 static ctl_table nf_ct_net_table[] = {
401         {
402                 .ctl_name       = CTL_NET,
403                 .procname       = "net",
404                 .mode           = 0555,
405                 .child          = nf_ct_netfilter_table,
406         },
407         { .ctl_name = 0 }
408 };
409 EXPORT_SYMBOL_GPL(nf_ct_log_invalid);
410 #endif /* CONFIG_SYSCTL */
411
412 static int __init nf_conntrack_standalone_init(void)
413 {
414 #ifdef CONFIG_PROC_FS
415         struct proc_dir_entry *proc, *proc_stat;
416 #endif
417         int ret = 0;
418
419         ret = nf_conntrack_init();
420         if (ret < 0)
421                 return ret;
422
423 #ifdef CONFIG_PROC_FS
424         proc = proc_net_fops_create("nf_conntrack", 0440, &ct_file_ops);
425         if (!proc) goto cleanup_init;
426
427         proc_stat = create_proc_entry("nf_conntrack", S_IRUGO, proc_net_stat);
428         if (!proc_stat)
429                 goto cleanup_proc;
430
431         proc_stat->proc_fops = &ct_cpu_seq_fops;
432         proc_stat->owner = THIS_MODULE;
433 #endif
434 #ifdef CONFIG_SYSCTL
435         nf_ct_sysctl_header = register_sysctl_table(nf_ct_net_table);
436         if (nf_ct_sysctl_header == NULL) {
437                 printk("nf_conntrack: can't register to sysctl.\n");
438                 ret = -ENOMEM;
439                 goto cleanup_proc_stat;
440         }
441 #endif
442         return ret;
443
444 #ifdef CONFIG_SYSCTL
445  cleanup_proc_stat:
446 #endif
447 #ifdef CONFIG_PROC_FS
448         remove_proc_entry("nf_conntrack", proc_net_stat);
449  cleanup_proc:
450         proc_net_remove("nf_conntrack");
451  cleanup_init:
452 #endif /* CNFIG_PROC_FS */
453         nf_conntrack_cleanup();
454         return ret;
455 }
456
457 static void __exit nf_conntrack_standalone_fini(void)
458 {
459 #ifdef CONFIG_SYSCTL
460         unregister_sysctl_table(nf_ct_sysctl_header);
461 #endif
462 #ifdef CONFIG_PROC_FS
463         remove_proc_entry("nf_conntrack", proc_net_stat);
464         proc_net_remove("nf_conntrack");
465 #endif /* CNFIG_PROC_FS */
466         nf_conntrack_cleanup();
467 }
468
469 module_init(nf_conntrack_standalone_init);
470 module_exit(nf_conntrack_standalone_fini);
471
472 /* Some modules need us, but don't depend directly on any symbol.
473    They should call this. */
474 void need_conntrack(void)
475 {
476 }
477 EXPORT_SYMBOL_GPL(need_conntrack);