-
Notifications
You must be signed in to change notification settings - Fork 733
/
uoa.c
1100 lines (927 loc) · 31.4 KB
/
uoa.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* DPVS is a software load balancer (Virtual Server) based on DPDK.
*
* Copyright (C) 2021 iQIYI (www.iqiyi.com).
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*
* UDP Option of Address (UOA) Kernel Module for Real Server.
* it refers TOA of LVS and ip_vs kernel module.
*
* [email protected], Feb 2018, initial.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/version.h>
#include <linux/err.h>
#include <linux/time.h>
#include <linux/skbuff.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv4.h>
#include <net/protocol.h>
#include <net/udp.h>
#include <net/inet_common.h>
#include <net/net_namespace.h>
#include <linux/uaccess.h>
#include <linux/netdevice.h>
#include <linux/fs.h>
#include <linux/sysctl.h>
#include <linux/proc_fs.h>
#include <linux/kallsyms.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/atomic.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/timer.h>
#include <linux/vmalloc.h>
#include <asm/pgtable_types.h>
#if LINUX_VERSION_CODE < KERNEL_VERSION(3,3,0)
#include <net/ipv6.h> /* ipv6_skip_exthdr */
#endif
#if LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0)
#define HAVE_PROC_OPS
#endif
#define UOA_NEED_EXTRA
#include "uoa_extra.h"
#include "uoa.h"
struct kr_ipopt_uoa {
__u8 op_code;
__u8 op_len;
__be16 op_port;
union inet_addr op_addr;
} __attribute__((__packed__));
/* uoa mapping hash table */
struct uoa_map {
struct hlist_node hlist;
atomic_t refcnt;
struct timer_list timer;
/* tuples as hash key */
__be16 af;
union inet_addr saddr;
union inet_addr daddr;
__be16 sport;
__be16 dport;
struct kr_ipopt_uoa optuoa;
};
static int uoa_debug = 0;
module_param_named(uoa_debug, uoa_debug, int, 0444);
MODULE_PARM_DESC(uoa_debug, "enable UOA debug by setting it to 1");
static int uoa_map_timeout = 360;
module_param_named(uoa_map_timeout, uoa_map_timeout, int, 0444);
MODULE_PARM_DESC(uoa_map_timeout, "UOA mapping timeout in second");
static int uoa_map_tab_bits = 12;
module_param_named(uoa_map_tab_bits, uoa_map_tab_bits, int, 0444);
MODULE_PARM_DESC(uoa_map_tab_bits, "UOA mapping table hash size");
static int uoa_hook_forward = 0;
module_param_named(uoa_hook_forward, uoa_hook_forward, int, 0444);
MODULE_PARM_DESC(uoa_hook_forward, "also parse UOA data in netfilter FORWARD chain (INPUT chain only by default)");
static int uoa_map_tab_size __read_mostly;
static int uoa_map_tab_mask __read_mostly;
static struct hlist_head *uoa_map_tab __read_mostly; /* mapping table */
static struct kmem_cache *uoa_map_cache __read_mostly;
static unsigned int uoa_map_rnd __read_mostly;
static atomic_t uoa_map_count = ATOMIC_INIT(0);
static int ipv6_hdrlen(const struct sk_buff *skb);
/* uoa mapping table lock array */
#define UOA_MAP_LOCKARR_BITS 5
#define UOA_MAP_LOCKARR_SIZE (1<<UOA_MAP_LOCKARR_BITS)
#define UOA_MAP_LOCKARR_MASK (UOA_MAP_LOCKARR_SIZE-1)
struct uoa_map_lock {
spinlock_t lock;
} __attribute__((__aligned__(SMP_CACHE_BYTES)));
static struct uoa_map_lock
__uoa_map_tab_lock_array[UOA_MAP_LOCKARR_SIZE] __cacheline_aligned;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,15,0)
static void uoa_map_expire(struct timer_list *timer);
#else
static void uoa_map_expire(unsigned long data);
#endif
static inline void um_lock_bh(unsigned int hash)
{
int i = hash & UOA_MAP_LOCKARR_MASK;
spin_lock_bh(&__uoa_map_tab_lock_array[i].lock);
}
static inline void um_unlock_bh(unsigned int hash)
{
int i = hash & UOA_MAP_LOCKARR_MASK;
spin_unlock_bh(&__uoa_map_tab_lock_array[i].lock);
}
/* per-cpu and global statistics */
struct uoa_stats {
struct uoa_kstats kstats;
spinlock_t lock;
struct uoa_cpu_stats __percpu *cpustats;
};
static struct uoa_stats uoa_stats;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,1,0)
#define UOA_STATS_INC(_f_) do { \
struct uoa_cpu_stats *s = this_cpu_ptr(uoa_stats.cpustats); \
u64_stats_update_begin(&s->syncp); \
s->_f_++; \
u64_stats_update_end(&s->syncp); \
uoa_stats.kstats._f_++; \
} while (0)
#else
#define UOA_STATS_INC(_f_) do { \
struct uoa_cpu_stats *s = this_cpu_ptr(uoa_stats.cpustats); \
s->_f_++; \
uoa_stats.kstats._f_++; \
} while (0)
#endif
static int uoa_stats_show(struct seq_file *seq, void *arg)
{
struct uoa_kstats ks;
spin_lock_bh(&uoa_stats.lock);
ks = uoa_stats.kstats;
spin_unlock_bh(&uoa_stats.lock);
seq_puts(seq, " Success Miss Invalid|UOA Got None Saved Ack-Fail\n");
seq_printf(seq, "%8llu %8llu %8llu %8llu %8llu %8llu %8llu\n",
ks.success, ks.miss, ks.invalid,
ks.uoa_got, ks.uoa_none, ks.uoa_saved, ks.uoa_ack_fail);
return 0;
}
static int uoa_stats_percpu_show(struct seq_file *seq, void *arg)
{
int i;
seq_puts(seq, "CPU Success Miss Invalid|UOA Got None Saved Ack-Fail\n");
for_each_possible_cpu(i) {
struct uoa_cpu_stats *s = per_cpu_ptr(uoa_stats.cpustats, i);
__u64 success, miss, invalid, got, none, saved, ack_fail;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,1,0)
unsigned int start;
do {
#if LINUX_VERSION_CODE >= KERNEL_VERSION(6,3,0) || \
( defined(RHEL_MAJOR) && ((RHEL_MAJOR == 9 && RHEL_MINOR > 3) || RHEL_MAJOR > 9))
start = u64_stats_fetch_begin(&s->syncp);
#else
start = u64_stats_fetch_begin_irq(&s->syncp);
#endif
#endif
success = s->success;
miss = s->miss;
invalid = s->invalid;
got = s->uoa_got;
none = s->uoa_none;
saved = s->uoa_saved;
ack_fail = s->uoa_ack_fail;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,1,0)
#if LINUX_VERSION_CODE >= KERNEL_VERSION(6,3,0) || \
( defined(RHEL_MAJOR) && ((RHEL_MAJOR == 9 && RHEL_MINOR > 3) || RHEL_MAJOR > 9))
} while (u64_stats_fetch_retry(&s->syncp, start));
#else
} while (u64_stats_fetch_retry_irq(&s->syncp, start));
#endif
#endif
seq_printf(seq,
"%3X %8llu %8llu %8llu %8llu %8llu %8llu %8llu\n",
i, success, miss, invalid, got, none, saved, ack_fail);
}
return 0;
}
static int uoa_stats_seq_open(struct inode *inode, struct file *file)
{
return single_open(file, uoa_stats_show, NULL);
}
static int uoa_stats_percpu_seq_open(struct inode *inode, struct file *file)
{
return single_open(file, uoa_stats_percpu_show, NULL);
}
#ifdef HAVE_PROC_OPS
static const struct proc_ops uoa_stats_fops = {
.proc_open = uoa_stats_seq_open,
.proc_read = seq_read,
.proc_lseek = seq_lseek,
.proc_release = single_release,
};
static const struct proc_ops uoa_stats_percpu_fops = {
.proc_open = uoa_stats_percpu_seq_open,
.proc_read = seq_read,
.proc_lseek = seq_lseek,
.proc_release = single_release,
};
#else
static const struct file_operations uoa_stats_fops = {
.owner = THIS_MODULE,
.open = uoa_stats_seq_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static const struct file_operations uoa_stats_percpu_fops = {
.owner = THIS_MODULE,
.open = uoa_stats_percpu_seq_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
#endif
static int uoa_stats_init(void)
{
int i;
spin_lock_init(&uoa_stats.lock);
memset(&uoa_stats.kstats, 0, sizeof(struct uoa_kstats));
uoa_stats.cpustats = alloc_percpu(struct uoa_cpu_stats);
if (!uoa_stats.cpustats) {
pr_err("fail to alloc percpu stats\n");
return -ENOMEM;
}
for_each_possible_cpu(i) {
struct uoa_cpu_stats *cs;
cs = per_cpu_ptr(uoa_stats.cpustats, i);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,1,0)
u64_stats_init(&cs->syncp);
#endif
}
proc_create("uoa_stats", 0, init_net.proc_net, &uoa_stats_fops);
proc_create("uoa_stats_percpu", 0, init_net.proc_net,
&uoa_stats_percpu_fops);
return 0;
}
static void uoa_stats_exit(void)
{
remove_proc_entry("uoa_stats", init_net.proc_net);
remove_proc_entry("uoa_stats_percpu", init_net.proc_net);
free_percpu(uoa_stats.cpustats);
}
static inline void uoa_map_dump(const struct uoa_map *um, const char *pref)
{
int real_af;
if (likely(!uoa_debug))
return;
if (um->optuoa.op_len == IPOLEN_UOA_IPV6)
real_af = AF_INET6;
else
real_af = AF_INET;
if (AF_INET == um->af) {
if (real_af == AF_INET) {
pr_info("%s %pI4:%d->%pI4:%d real %pI4:%d, refcnt %d\n", pref ? : "",
&um->saddr.in, ntohs(um->sport), &um->daddr.in, ntohs(um->dport),
&um->optuoa.op_addr.in, ntohs(um->optuoa.op_port),
atomic_read(&um->refcnt));
} else {
pr_info("%s %pI4:%d->%pI4:%d real [%pI6]:%d, refcnt %d\n", pref ? : "",
&um->saddr.in, ntohs(um->sport), &um->daddr.in, ntohs(um->dport),
&um->optuoa.op_addr.in6, ntohs(um->optuoa.op_port),
atomic_read(&um->refcnt));
}
} else {
if (real_af == AF_INET) {
pr_info("%s [%pI6]:%d->[%pI6]:%d real %pI4:%d, refcnt %d\n", pref ? : "",
&um->saddr.in6, ntohs(um->sport), &um->daddr.in6, ntohs(um->dport),
&um->optuoa.op_addr.in, ntohs(um->optuoa.op_port),
atomic_read(&um->refcnt));
} else {
pr_info("%s [%pI6]:%d->[%pI6]:%d real [%pI6]:%d, refcnt %d\n", pref ? : "",
&um->saddr.in6, ntohs(um->sport), &um->daddr.in6, ntohs(um->dport),
&um->optuoa.op_addr.in6, ntohs(um->optuoa.op_port),
atomic_read(&um->refcnt));
}
}
}
static inline unsigned int __uoa_map_hash_key(__be16 af,
const union inet_addr *saddr,
const union inet_addr *daddr,
__be16 sport, __be16 dport)
{
/* do not cal daddr, it could be zero for wildcard lookup */
uint32_t saddr_fold;
saddr_fold = inet_addr_fold(af, saddr);
return jhash_3words(saddr_fold, sport, dport, uoa_map_rnd) &
uoa_map_tab_mask;
}
static inline unsigned int uoa_map_hash_key(const struct uoa_map *um)
{
return __uoa_map_hash_key(um->af, &um->saddr, &um->daddr,
um->sport, um->dport);
}
static inline void uoa_map_hash(struct uoa_map *um)
{
unsigned int hash = uoa_map_hash_key(um);
struct hlist_head *head = &uoa_map_tab[hash];
struct uoa_map *cur;
#if LINUX_VERSION_CODE < KERNEL_VERSION(3,8,0)
struct hlist_node *node;
#endif
um_lock_bh(hash);
/* overwrite existing mapping */
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0)
hlist_for_each_entry_rcu(cur, head, hlist) {
#else
hlist_for_each_entry_rcu(cur, node, head, hlist) {
#endif
if (um->af == cur->af &&
inet_addr_equal(um->af, &um->saddr, &cur->saddr) &&
inet_addr_equal(um->af, &um->daddr, &cur->daddr) &&
um->sport == cur->sport &&
um->dport == cur->dport) {
/* update */
memmove(&cur->optuoa, &um->optuoa, sizeof(cur->optuoa));
mod_timer(&cur->timer, jiffies + uoa_map_timeout * HZ);
kmem_cache_free(uoa_map_cache, um);
uoa_map_dump(cur, "update:");
goto hashed;
}
}
/* not exist */
hlist_add_head_rcu(&um->hlist, head);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,15,0)
timer_setup(&um->timer, uoa_map_expire, 0);
#else
setup_timer(&um->timer, uoa_map_expire, (unsigned long)um);
#endif
mod_timer(&um->timer, jiffies + uoa_map_timeout * HZ);
atomic_inc(&uoa_map_count);
uoa_map_dump(um, "new:");
hashed:
um_unlock_bh(hash);
}
static inline int uoa_map_unhash(struct uoa_map *um)
{
unsigned int hash = uoa_map_hash_key(um);
int err = -1;
um_lock_bh(hash);
if (atomic_read(&um->refcnt) == 0) {
hlist_del_rcu(&um->hlist);
atomic_dec(&uoa_map_count);
err = 0;
}
um_unlock_bh(hash);
return err;
}
static inline struct uoa_map *uoa_map_get(__be16 af,
union inet_addr *saddr,
union inet_addr *daddr,
__be16 sport, __be16 dport)
{
unsigned int hash = __uoa_map_hash_key(af, saddr, daddr, sport, dport);
struct hlist_head *head = &uoa_map_tab[hash];
struct uoa_map *um = NULL;
#if LINUX_VERSION_CODE < KERNEL_VERSION(3,8,0)
struct hlist_node *node;
#endif
um_lock_bh(hash);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0)
hlist_for_each_entry_rcu(um, head, hlist) {
#else
hlist_for_each_entry_rcu(um, node, head, hlist) {
#endif
/* we allow daddr being set to wildcard (zero),
* since UDP server may bind INADDR_ANY */
if (um->af == af &&
inet_addr_equal(af, &um->saddr, saddr) &&
(inet_is_addr_any(af, daddr) ||
inet_addr_equal(af, &um->daddr, daddr)) &&
um->sport == sport &&
um->dport == dport) {
mod_timer(&um->timer, jiffies + uoa_map_timeout * HZ);
atomic_inc(&um->refcnt);
um_unlock_bh(hash);
return um;
}
}
um_unlock_bh(hash);
return NULL;
}
static inline void uoa_map_put(struct uoa_map *um)
{
atomic_dec(&um->refcnt);
}
static inline void __uoa_map_expire(struct uoa_map *um, struct timer_list *timer)
{
if (uoa_map_unhash(um) != 0) {
/* try again if some one is using it */
mod_timer(timer, jiffies + uoa_map_timeout * HZ);
uoa_map_dump(um, "expire delayed:");
return;
}
uoa_map_dump(um, "del:");
del_timer(&um->timer);
kmem_cache_free(uoa_map_cache, um);
}
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,15,0)
static void uoa_map_expire(struct timer_list *timer)
{
struct uoa_map *um = from_timer(um, timer, timer);
__uoa_map_expire(um, timer);
}
#else
static void uoa_map_expire(unsigned long data)
{
struct uoa_map *um = (struct uoa_map *)data;
__uoa_map_expire(um, &um->timer);
}
#endif
static void uoa_map_flush(void)
{
int i;
flush_again:
for (i = 0; i < uoa_map_tab_size; i++) {
struct uoa_map *um;
struct hlist_node *n;
struct hlist_head *head = &uoa_map_tab[i];
#if LINUX_VERSION_CODE < KERNEL_VERSION(3,8,0)
struct hlist_node *node;
#endif
um_lock_bh(i);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0)
hlist_for_each_entry_safe(um, n, head, hlist) {
#else
hlist_for_each_entry_safe(um, node, n, head, hlist) {
#endif
if (timer_pending(&um->timer))
del_timer(&um->timer);
if (atomic_read(&um->refcnt) != 0)
continue;
uoa_map_dump(um, "flu:");
hlist_del_rcu(&um->hlist);
atomic_dec(&uoa_map_count);
kmem_cache_free(uoa_map_cache, um);
}
um_unlock_bh(i);
}
if (atomic_read(&uoa_map_count) > 0) {
pr_debug("%s: again\n", __func__);
schedule();
goto flush_again;
}
}
static int uoa_so_set(struct sock *sk, int cmd,
#if LINUX_VERSION_CODE < KERNEL_VERSION(5, 9, 0)
void __user *user,
#else
sockptr_t arg,
#endif
unsigned int len)
{
return 0;
}
static int uoa_so_get(struct sock *sk, int cmd, void __user *user, int *len)
{
struct uoa_param_map map;
struct uoa_map *um;
int err;
if (cmd != UOA_SO_GET_LOOKUP) {
pr_warn("%s: bad cmd\n", __func__);
return -EINVAL;
}
if (*len < sizeof(struct uoa_param_map)) {
pr_warn("%s: bad param len\n", __func__);
return -EINVAL;
}
if (copy_from_user(&map, user, sizeof(struct uoa_param_map)) != 0)
return -EFAULT;
/* lookup uap mapping table */
um = uoa_map_get(map.af, &map.saddr, &map.daddr, map.sport, map.dport);
if (!um) {
if (uoa_debug) {
if (AF_INET == map.af) {
pr_warn("%s: not found: %pI4:%d->%pI4:%d\n", __func__,
&map.saddr.in, ntohs(map.sport),
&map.daddr.in, ntohs(map.dport));
} else {
pr_warn("%s: not found: [%pI6]:%d->[%pI6]:%d\n", __func__,
&map.saddr.in6, ntohs(map.sport),
&map.daddr.in6, ntohs(map.dport));
}
}
UOA_STATS_INC(miss);
return -ENOENT;
}
uoa_map_dump(um, "hit:");
if (likely(um->optuoa.op_code == IPOPT_UOA)) {
if (um->optuoa.op_len == IPOLEN_UOA_IPV4) {
map.real_af = AF_INET;
memmove(&map.real_saddr.in, &um->optuoa.op_addr.in,
sizeof(map.real_saddr.in));
map.real_sport = um->optuoa.op_port;
UOA_STATS_INC(success);
err = 0;
} else {
if (um->optuoa.op_len == IPOLEN_UOA_IPV6) {
map.real_af = AF_INET6;
memmove(&map.real_saddr.in6, &um->optuoa.op_addr.in6,
sizeof(map.real_saddr.in6));
map.real_sport = um->optuoa.op_port;
UOA_STATS_INC(success);
err = 0;
} else {
UOA_STATS_INC(invalid);
err = -EFAULT;
}
}
} else {
UOA_STATS_INC(invalid);
err = -EFAULT;
}
if (copy_to_user(user, &map, sizeof(struct uoa_param_map)) != 0)
err = -EFAULT;
*len = sizeof(struct uoa_param_map);
uoa_map_put(um);
return err;
}
static struct nf_sockopt_ops uoa_sockopts = {
.pf = PF_INET,
.owner = THIS_MODULE,
/* set */
.set_optmin = UOA_BASE_CTL,
.set_optmax = UOA_SO_SET_MAX + 1,
.set = uoa_so_set,
/* get */
.get_optmin = UOA_BASE_CTL,
.get_optmax = UOA_SO_GET_MAX + 1,
.get = uoa_so_get,
};
static int uoa_map_init(void)
{
int i, err;
/* mapping table */
uoa_map_tab_size = 1 << uoa_map_tab_bits;
uoa_map_tab_mask = uoa_map_tab_size - 1;
uoa_map_tab = vmalloc(uoa_map_tab_size * sizeof(*uoa_map_tab));
if (!uoa_map_tab) {
pr_err("no memory for uoa mapping table\n");
return -ENOMEM;
}
atomic_set(&uoa_map_count, 0);
get_random_bytes(&uoa_map_rnd, sizeof(uoa_map_rnd));
for (i = 0; i < uoa_map_tab_size; i++)
INIT_HLIST_HEAD(&uoa_map_tab[i]);
for (i = 0; i < UOA_MAP_LOCKARR_SIZE; i++)
spin_lock_init(&__uoa_map_tab_lock_array[i].lock);
/* mapping cache */
uoa_map_cache = kmem_cache_create("uoa_map",
sizeof(struct uoa_map), 0,
SLAB_HWCACHE_ALIGN, NULL);
if (!uoa_map_cache) {
pr_err("fail to create uoa_map cache\n");
vfree(uoa_map_tab);
return -ENOMEM;
}
/* socket option */
err = nf_register_sockopt(&uoa_sockopts);
if (err != 0) {
pr_err("fail to register sockopt\n");
kmem_cache_destroy(uoa_map_cache);
vfree(uoa_map_tab);
return -ENOMEM;
}
pr_debug("mapping hash initialed, size %d\n", uoa_map_tab_size);
return 0;
}
static void uoa_map_exit(void)
{
nf_unregister_sockopt(&uoa_sockopts);
kmem_cache_destroy(uoa_map_cache);
vfree(uoa_map_tab);
}
/*
* "ACK" is an empty payload UDP/IP packet.
* UOA sender (LB) will handle the "ACK" and eat it,
* it should not be forwarded by LB to original UDP sender.
*/
static int uoa_send_ack(const struct sk_buff *oskb)
{
/* TODO: */
return 0;
}
static struct uoa_map *uoa_parse_ipopt(__be16 af, unsigned char *optptr,
int optlen, void *iph,
__be16 sport, __be16 dport)
{
int l;
struct uoa_map *um = NULL;
for (l = optlen; l > 0; ) {
switch (*optptr) {
case IPOPT_END:
break;
case IPOPT_NOOP:
l--;
optptr++;
continue;
}
if (unlikely(l < 2))
goto out; /* invalid */
optlen = optptr[1];
if (unlikely(optlen < 2 || optlen > l))
goto out; /* invalid */
if (*optptr == IPOPT_UOA) {
UOA_STATS_INC(uoa_got);
um = kmem_cache_alloc(uoa_map_cache, GFP_ATOMIC);
if (!um) {
UOA_STATS_INC(uoa_miss);
goto out;
}
atomic_set(&um->refcnt, 0);
um->af = af;
if (AF_INET == af) {
memmove(&um->saddr.in, &((struct iphdr *)iph)->saddr,
sizeof(struct in_addr));
memmove(&um->daddr.in, &((struct iphdr *)iph)->daddr,
sizeof(struct in_addr));
} else {
/* ipv6 */
memmove(&um->saddr.in6, &((struct ipv6hdr *)iph)->saddr,
sizeof(struct in6_addr));
memmove(&um->daddr.in6, &((struct ipv6hdr *)iph)->daddr,
sizeof(struct in6_addr));
}
um->sport = sport;
um->dport = dport;
memcpy(&um->optuoa, optptr, optlen);
UOA_STATS_INC(uoa_saved);
return um;
}
l -= optlen;
optptr += optlen;
continue;
}
/* no UOA option */
UOA_STATS_INC(uoa_none);
out:
return NULL;
}
/* get uoa info from uoa-option in IP header. */
static struct uoa_map *uoa_iph_rcv(const struct iphdr *iph, struct sk_buff *skb)
{
struct udphdr *uh;
int optlen;
unsigned char *optptr;
struct uoa_map *um = NULL;
if (!pskb_may_pull(skb, ip_hdrlen(skb) + sizeof(struct udphdr)))
return NULL;
uh = (void *)iph + ip_hdrlen(skb);
optlen = ip_hdrlen(skb) - sizeof(struct iphdr);
optptr = (unsigned char *)(iph + 1);
um = uoa_parse_ipopt(AF_INET, optptr, optlen,
(void *)iph, uh->source, uh->dest);
if (um && uoa_send_ack(skb) != 0) {
UOA_STATS_INC(uoa_ack_fail);
pr_warn("fail to send UOA ACK\n");
}
return um;
}
/* get uoa info from private option protocol. */
static struct uoa_map *uoa_opp_rcv(__be16 af, void *iph, struct sk_buff *skb)
{
struct opphdr *opph;
struct udphdr *uh;
int optlen, opplen;
unsigned char *optptr;
struct uoa_map *um = NULL;
int iphdrlen = ((AF_INET6 == af) ? ipv6_hdrlen(skb) : ip_hdrlen(skb));
if (!pskb_may_pull(skb, iphdrlen + sizeof(struct opphdr)))
return NULL;
opph = iph + iphdrlen;
opplen = ntohs(opph->length);
if (unlikely(opph->protocol != IPPROTO_UDP)) {
pr_warn("bad opp header\n");
return NULL;
}
if (!pskb_may_pull(skb, iphdrlen + opplen + sizeof(*uh)))
return NULL;
uh = iph + iphdrlen + opplen;
optlen = opplen - sizeof(*opph);
optptr = (unsigned char *)(opph + 1);
/* try parse UOA option from ip-options */
um = uoa_parse_ipopt(af, optptr, optlen, iph, uh->source, uh->dest);
if (um && uoa_send_ack(skb) != 0) {
UOA_STATS_INC(uoa_ack_fail);
pr_warn("fail to send UOA ACK\n");
}
/*
* "remove" private option protocol, then adjust IP header
* protocol, tot_len and checksum. these could be slow ?
*/
skb_set_transport_header(skb, iphdrlen + opplen);
/* Old kernel like 2.6.32 use "iph->ihl" rather "skb->transport_header"
* to get UDP header offset. The UOA private protocol data should be
* erased here, but this should move skb data and harm perfomance. As a
* compromise, we convert the private protocol data into NOP IP option
* data if possible.*/
if (AF_INET == af) {
if (((struct iphdr *)iph)->ihl + (opplen >> 2) < 16) {
((struct iphdr *)iph)->ihl += (opplen >> 2);
/* need change it to parse transport layer */
((struct iphdr *)iph)->protocol = opph->protocol;
memset(opph, IPOPT_NOOP, opplen);
} else {
pr_warn("IP header has no room to convert uoa data into option.\n");
}
/* re-calc checksum */
ip_send_check(iph);
} else {
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3,0,0)
/* do as upper ipv4, handle for old kernel version */
int payload_len = ntohs(((struct ipv6hdr *)iph)->payload_len);
((struct ipv6hdr *)iph)->payload_len = htons(payload_len - opplen);
((struct ipv6hdr *)iph)->nexthdr = opph->protocol;
memmove(iph + iphdrlen, uh, ntohs(uh->len));
skb_set_transport_header(skb, iphdrlen);
#else
((struct ipv6hdr *)iph)->nexthdr = opph->protocol;
#endif
}
return um;
}
static struct uoa_map *uoa_skb_rcv_opt(struct sk_buff *skb)
{
struct iphdr *iph = ip_hdr(skb);
__be16 af = ((6 == iph->version) ? AF_INET6 : AF_INET);
if (AF_INET6 == af) {
struct ipv6hdr *ip6h = ipv6_hdr(skb);
if (ipv6_hdrlen(skb) != sizeof(struct ipv6hdr)) {
if (uoa_debug) {
pr_info("we not support uoa with ipv6 ext header now.");
}
}
if (unlikely(ip6h->nexthdr == IPPROTO_OPT)) {
return uoa_opp_rcv(af, (void *)ip6h, skb);
}
} else {
if (unlikely(iph->ihl > 5) && iph->protocol == IPPROTO_UDP)
return uoa_iph_rcv(iph, skb);
else if (unlikely(iph->protocol == IPPROTO_OPT))
return uoa_opp_rcv(af, (void *)iph, skb);
}
UOA_STATS_INC(uoa_none);
return NULL;
}
/*
* the definition of nf_hookfn changes a lot.
* may need modify according to the Kernel version.
*/
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,3,0)
static unsigned int uoa_ip_local_in(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
#elif RHEL_RELEASE_CODE >= RHEL_RELEASE_VERSION(7,2)
static unsigned int uoa_ip_local_in(const struct nf_hook_ops *ops,
struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const struct nf_hook_state *state)
#elif RHEL_RELEASE_CODE >= RHEL_RELEASE_VERSION(6,4)
static unsigned int uoa_ip_local_in(unsigned int hooknum,
struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
#else
#error "Pls modify the definition according to kernel version."
#endif
{
struct uoa_map *um;
um = uoa_skb_rcv_opt(skb);
if (um)
uoa_map_hash(um);
return NF_ACCEPT;
}
/*
* use nf LOCAL_IN hook to get UOA option.
*/
static struct nf_hook_ops uoa_nf_hook_ops[] __read_mostly = {
{
.hook = uoa_ip_local_in,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_LOCAL_IN,
.priority = NF_IP_PRI_NAT_SRC + 1,
},
{
// do NOT register unless module param `uoa_hook_forward` is enabled
.hook = uoa_ip_local_in,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_FORWARD,
.priority = NF_IP_PRI_LAST - 1,
},
};
static struct nf_hook_ops uoa_nf_hook_ops6[] __read_mostly = {
{
.hook = uoa_ip_local_in,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_LOCAL_IN,
.priority = NF_IP_PRI_NAT_SRC + 1,
},
{
// do NOT register unless module param `uoa_hook_forward` is enabled
.hook = uoa_ip_local_in,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_FORWARD,
.priority = NF_IP_PRI_LAST - 1,
},
};
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,3,0)
static int __net_init __uoa_init(struct net *net)
{
int ret = -ENOMEM;
ret = nf_register_net_hooks(net, uoa_nf_hook_ops, ARRAY_SIZE(uoa_nf_hook_ops));
if (ret < 0)
goto ops_hook_fail;
ret = nf_register_net_hooks(&init_net, uoa_nf_hook_ops6,
ARRAY_SIZE(uoa_nf_hook_ops6));
if (ret < 0)
goto ops6_hook_fail;
return 0;
/*
* Error handling
*/
ops6_hook_fail:
nf_unregister_net_hooks(net, uoa_nf_hook_ops,
ARRAY_SIZE(uoa_nf_hook_ops));
ops_hook_fail: