summaryrefslogtreecommitdiffstats
path: root/net/batman-adv/bat_iv_ogm.c
blob: 948a5b45474d397ae9101467f631c68b7261ea4c (plain)
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
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
/* Copyright (C) 2007-2016  B.A.T.M.A.N. contributors:
 *
 * Marek Lindner, Simon Wunderlich
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see <http://www.gnu.org/licenses/>.
 */

#include "bat_algo.h"
#include "main.h"

#include <linux/atomic.h>
#include <linux/bitmap.h>
#include <linux/bitops.h>
#include <linux/bug.h>
#include <linux/byteorder/generic.h>
#include <linux/cache.h>
#include <linux/errno.h>
#include <linux/etherdevice.h>
#include <linux/fs.h>
#include <linux/if_ether.h>
#include <linux/init.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/lockdep.h>
#include <linux/netdevice.h>
#include <linux/pkt_sched.h>
#include <linux/printk.h>
#include <linux/random.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/seq_file.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/workqueue.h>

#include "bitarray.h"
#include "hard-interface.h"
#include "hash.h"
#include "network-coding.h"
#include "originator.h"
#include "packet.h"
#include "routing.h"
#include "send.h"
#include "translation-table.h"
#include "tvlv.h"

static void batadv_iv_send_outstanding_bat_ogm_packet(struct work_struct *work);

/**
 * enum batadv_dup_status - duplicate status
 * @BATADV_NO_DUP: the packet is no duplicate
 * @BATADV_ORIG_DUP: OGM is a duplicate in the originator (but not for the
 *  neighbor)
 * @BATADV_NEIGH_DUP: OGM is a duplicate for the neighbor
 * @BATADV_PROTECTED: originator is currently protected (after reboot)
 */
enum batadv_dup_status {
	BATADV_NO_DUP = 0,
	BATADV_ORIG_DUP,
	BATADV_NEIGH_DUP,
	BATADV_PROTECTED,
};

/**
 * batadv_ring_buffer_set - update the ring buffer with the given value
 * @lq_recv: pointer to the ring buffer
 * @lq_index: index to store the value at
 * @value: value to store in the ring buffer
 */
static void batadv_ring_buffer_set(u8 lq_recv[], u8 *lq_index, u8 value)
{
	lq_recv[*lq_index] = value;
	*lq_index = (*lq_index + 1) % BATADV_TQ_GLOBAL_WINDOW_SIZE;
}

/**
 * batadv_ring_buffer_avg - compute the average of all non-zero values stored
 * in the given ring buffer
 * @lq_recv: pointer to the ring buffer
 *
 * Return: computed average value.
 */
static u8 batadv_ring_buffer_avg(const u8 lq_recv[])
{
	const u8 *ptr;
	u16 count = 0;
	u16 i = 0;
	u16 sum = 0;

	ptr = lq_recv;

	while (i < BATADV_TQ_GLOBAL_WINDOW_SIZE) {
		if (*ptr != 0) {
			count++;
			sum += *ptr;
		}

		i++;
		ptr++;
	}

	if (count == 0)
		return 0;

	return (u8)(sum / count);
}

/**
 * batadv_iv_ogm_orig_free - free the private resources allocated for this
 *  orig_node
 * @orig_node: the orig_node for which the resources have to be free'd
 */
static void batadv_iv_ogm_orig_free(struct batadv_orig_node *orig_node)
{
	kfree(orig_node->bat_iv.bcast_own);
	kfree(orig_node->bat_iv.bcast_own_sum);
}

/**
 * batadv_iv_ogm_orig_add_if - change the private structures of the orig_node to
 *  include the new hard-interface
 * @orig_node: the orig_node that has to be changed
 * @max_if_num: the current amount of interfaces
 *
 * Return: 0 on success, a negative error code otherwise.
 */
static int batadv_iv_ogm_orig_add_if(struct batadv_orig_node *orig_node,
				     int max_if_num)
{
	void *data_ptr;
	size_t old_size;
	int ret = -ENOMEM;

	spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);

	old_size = (max_if_num - 1) * sizeof(unsigned long) * BATADV_NUM_WORDS;
	data_ptr = kmalloc_array(max_if_num,
				 BATADV_NUM_WORDS * sizeof(unsigned long),
				 GFP_ATOMIC);
	if (!data_ptr)
		goto unlock;

	memcpy(data_ptr, orig_node->bat_iv.bcast_own, old_size);
	kfree(orig_node->bat_iv.bcast_own);
	orig_node->bat_iv.bcast_own = data_ptr;

	data_ptr = kmalloc_array(max_if_num, sizeof(u8), GFP_ATOMIC);
	if (!data_ptr)
		goto unlock;

	memcpy(data_ptr, orig_node->bat_iv.bcast_own_sum,
	       (max_if_num - 1) * sizeof(u8));
	kfree(orig_node->bat_iv.bcast_own_sum);
	orig_node->bat_iv.bcast_own_sum = data_ptr;

	ret = 0;

unlock:
	spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);

	return ret;
}

/**
 * batadv_iv_ogm_drop_bcast_own_entry - drop section of bcast_own
 * @orig_node: the orig_node that has to be changed
 * @max_if_num: the current amount of interfaces
 * @del_if_num: the index of the interface being removed
 */
static void
batadv_iv_ogm_drop_bcast_own_entry(struct batadv_orig_node *orig_node,
				   int max_if_num, int del_if_num)
{
	size_t chunk_size;
	size_t if_offset;
	void *data_ptr;

	lockdep_assert_held(&orig_node->bat_iv.ogm_cnt_lock);

	chunk_size = sizeof(unsigned long) * BATADV_NUM_WORDS;
	data_ptr = kmalloc_array(max_if_num, chunk_size, GFP_ATOMIC);
	if (!data_ptr)
		/* use old buffer when new one could not be allocated */
		data_ptr = orig_node->bat_iv.bcast_own;

	/* copy first part */
	memmove(data_ptr, orig_node->bat_iv.bcast_own, del_if_num * chunk_size);

	/* copy second part */
	if_offset = (del_if_num + 1) * chunk_size;
	memmove((char *)data_ptr + del_if_num * chunk_size,
		(uint8_t *)orig_node->bat_iv.bcast_own + if_offset,
		(max_if_num - del_if_num) * chunk_size);

	/* bcast_own was shrunk down in new buffer; free old one */
	if (orig_node->bat_iv.bcast_own != data_ptr) {
		kfree(orig_node->bat_iv.bcast_own);
		orig_node->bat_iv.bcast_own = data_ptr;
	}
}

/**
 * batadv_iv_ogm_drop_bcast_own_sum_entry - drop section of bcast_own_sum
 * @orig_node: the orig_node that has to be changed
 * @max_if_num: the current amount of interfaces
 * @del_if_num: the index of the interface being removed
 */
static void
batadv_iv_ogm_drop_bcast_own_sum_entry(struct batadv_orig_node *orig_node,
				       int max_if_num, int del_if_num)
{
	size_t if_offset;
	void *data_ptr;

	lockdep_assert_held(&orig_node->bat_iv.ogm_cnt_lock);

	data_ptr = kmalloc_array(max_if_num, sizeof(u8), GFP_ATOMIC);
	if (!data_ptr)
		/* use old buffer when new one could not be allocated */
		data_ptr = orig_node->bat_iv.bcast_own_sum;

	memmove(data_ptr, orig_node->bat_iv.bcast_own_sum,
		del_if_num * sizeof(u8));

	if_offset = (del_if_num + 1) * sizeof(u8);
	memmove((char *)data_ptr + del_if_num * sizeof(u8),
		orig_node->bat_iv.bcast_own_sum + if_offset,
		(max_if_num - del_if_num) * sizeof(u8));

	/* bcast_own_sum was shrunk down in new buffer; free old one */
	if (orig_node->bat_iv.bcast_own_sum != data_ptr) {
		kfree(orig_node->bat_iv.bcast_own_sum);
		orig_node->bat_iv.bcast_own_sum = data_ptr;
	}
}

/**
 * batadv_iv_ogm_orig_del_if - change the private structures of the orig_node to
 *  exclude the removed interface
 * @orig_node: the orig_node that has to be changed
 * @max_if_num: the current amount of interfaces
 * @del_if_num: the index of the interface being removed
 *
 * Return: 0 on success, a negative error code otherwise.
 */
static int batadv_iv_ogm_orig_del_if(struct batadv_orig_node *orig_node,
				     int max_if_num, int del_if_num)
{
	spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);

	if (max_if_num == 0) {
		kfree(orig_node->bat_iv.bcast_own);
		kfree(orig_node->bat_iv.bcast_own_sum);
		orig_node->bat_iv.bcast_own = NULL;
		orig_node->bat_iv.bcast_own_sum = NULL;
	} else {
		batadv_iv_ogm_drop_bcast_own_entry(orig_node, max_if_num,
						   del_if_num);
		batadv_iv_ogm_drop_bcast_own_sum_entry(orig_node, max_if_num,
						       del_if_num);
	}

	spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);

	return 0;
}

/**
 * batadv_iv_ogm_orig_get - retrieve or create (if does not exist) an originator
 * @bat_priv: the bat priv with all the soft interface information
 * @addr: mac address of the originator
 *
 * Return: the originator object corresponding to the passed mac address or NULL
 * on failure.
 * If the object does not exists it is created an initialised.
 */
static struct batadv_orig_node *
batadv_iv_ogm_orig_get(struct batadv_priv *bat_priv, const u8 *addr)
{
	struct batadv_orig_node *orig_node;
	int size, hash_added;

	orig_node = batadv_orig_hash_find(bat_priv, addr);
	if (orig_node)
		return orig_node;

	orig_node = batadv_orig_node_new(bat_priv, addr);
	if (!orig_node)
		return NULL;

	spin_lock_init(&orig_node->bat_iv.ogm_cnt_lock);

	size = bat_priv->num_ifaces * sizeof(unsigned long) * BATADV_NUM_WORDS;
	orig_node->bat_iv.bcast_own = kzalloc(size, GFP_ATOMIC);
	if (!orig_node->bat_iv.bcast_own)
		goto free_orig_node;

	size = bat_priv->num_ifaces * sizeof(u8);
	orig_node->bat_iv.bcast_own_sum = kzalloc(size, GFP_ATOMIC);
	if (!orig_node->bat_iv.bcast_own_sum)
		goto free_orig_node;

	hash_added = batadv_hash_add(bat_priv->orig_hash, batadv_compare_orig,
				     batadv_choose_orig, orig_node,
				     &orig_node->hash_entry);
	if (hash_added != 0)
		goto free_orig_node;

	return orig_node;

free_orig_node:
	/* free twice, as batadv_orig_node_new sets refcount to 2 */
	batadv_orig_node_put(orig_node);
	batadv_orig_node_put(orig_node);

	return NULL;
}

static struct batadv_neigh_node *
batadv_iv_ogm_neigh_new(struct batadv_hard_iface *hard_iface,
			const u8 *neigh_addr,
			struct batadv_orig_node *orig_node,
			struct batadv_orig_node *orig_neigh)
{
	struct batadv_neigh_node *neigh_node;

	neigh_node = batadv_neigh_node_get_or_create(orig_node,
						     hard_iface, neigh_addr);
	if (!neigh_node)
		goto out;

	neigh_node->orig_node = orig_neigh;

out:
	return neigh_node;
}

static int batadv_iv_ogm_iface_enable(struct batadv_hard_iface *hard_iface)
{
	struct batadv_ogm_packet *batadv_ogm_packet;
	unsigned char *ogm_buff;
	u32 random_seqno;

	/* randomize initial seqno to avoid collision */
	get_random_bytes(&random_seqno, sizeof(random_seqno));
	atomic_set(&hard_iface->bat_iv.ogm_seqno, random_seqno);

	hard_iface->bat_iv.ogm_buff_len = BATADV_OGM_HLEN;
	ogm_buff = kmalloc(hard_iface->bat_iv.ogm_buff_len, GFP_ATOMIC);
	if (!ogm_buff)
		return -ENOMEM;

	hard_iface->bat_iv.ogm_buff = ogm_buff;

	batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
	batadv_ogm_packet->packet_type = BATADV_IV_OGM;
	batadv_ogm_packet->version = BATADV_COMPAT_VERSION;
	batadv_ogm_packet->ttl = 2;
	batadv_ogm_packet->flags = BATADV_NO_FLAGS;
	batadv_ogm_packet->reserved = 0;
	batadv_ogm_packet->tq = BATADV_TQ_MAX_VALUE;

	return 0;
}

static void batadv_iv_ogm_iface_disable(struct batadv_hard_iface *hard_iface)
{
	kfree(hard_iface->bat_iv.ogm_buff);
	hard_iface->bat_iv.ogm_buff = NULL;
}

static void batadv_iv_ogm_iface_update_mac(struct batadv_hard_iface *hard_iface)
{
	struct batadv_ogm_packet *batadv_ogm_packet;
	unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;

	batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
	ether_addr_copy(batadv_ogm_packet->orig,
			hard_iface->net_dev->dev_addr);
	ether_addr_copy(batadv_ogm_packet->prev_sender,
			hard_iface->net_dev->dev_addr);
}

static void
batadv_iv_ogm_primary_iface_set(struct batadv_hard_iface *hard_iface)
{
	struct batadv_ogm_packet *batadv_ogm_packet;
	unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;

	batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
	batadv_ogm_packet->ttl = BATADV_TTL;
}

/* when do we schedule our own ogm to be sent */
static unsigned long
batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv)
{
	unsigned int msecs;

	msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
	msecs += prandom_u32() % (2 * BATADV_JITTER);

	return jiffies + msecs_to_jiffies(msecs);
}

/* when do we schedule a ogm packet to be sent */
static unsigned long batadv_iv_ogm_fwd_send_time(void)
{
	return jiffies + msecs_to_jiffies(prandom_u32() % (BATADV_JITTER / 2));
}

/* apply hop penalty for a normal link */
static u8 batadv_hop_penalty(u8 tq, const struct batadv_priv *bat_priv)
{
	int hop_penalty = atomic_read(&bat_priv->hop_penalty);
	int new_tq;

	new_tq = tq * (BATADV_TQ_MAX_VALUE - hop_penalty);
	new_tq /= BATADV_TQ_MAX_VALUE;

	return new_tq;
}

/**
 * batadv_iv_ogm_aggr_packet - checks if there is another OGM attached
 * @buff_pos: current position in the skb
 * @packet_len: total length of the skb
 * @tvlv_len: tvlv length of the previously considered OGM
 *
 * Return: true if there is enough space for another OGM, false otherwise.
 */
static bool batadv_iv_ogm_aggr_packet(int buff_pos, int packet_len,
				      __be16 tvlv_len)
{
	int next_buff_pos = 0;

	next_buff_pos += buff_pos + BATADV_OGM_HLEN;
	next_buff_pos += ntohs(tvlv_len);

	return (next_buff_pos <= packet_len) &&
	       (next_buff_pos <= BATADV_MAX_AGGREGATION_BYTES);
}

/* send a batman ogm to a given interface */
static void batadv_iv_ogm_send_to_if(struct batadv_forw_packet *forw_packet,
				     struct batadv_hard_iface *hard_iface)
{
	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
	const char *fwd_str;
	u8 packet_num;
	s16 buff_pos;
	struct batadv_ogm_packet *batadv_ogm_packet;
	struct sk_buff *skb;
	u8 *packet_pos;

	if (hard_iface->if_status != BATADV_IF_ACTIVE)
		return;

	packet_num = 0;
	buff_pos = 0;
	packet_pos = forw_packet->skb->data;
	batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;

	/* adjust all flags and log packets */
	while (batadv_iv_ogm_aggr_packet(buff_pos, forw_packet->packet_len,
					 batadv_ogm_packet->tvlv_len)) {
		/* we might have aggregated direct link packets with an
		 * ordinary base packet
		 */
		if (forw_packet->direct_link_flags & BIT(packet_num) &&
		    forw_packet->if_incoming == hard_iface)
			batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
		else
			batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;

		if (packet_num > 0 || !forw_packet->own)
			fwd_str = "Forwarding";
		else
			fwd_str = "Sending own";

		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "%s %spacket (originator %pM, seqno %u, TQ %d, TTL %d, IDF %s) on interface %s [%pM]\n",
			   fwd_str, (packet_num > 0 ? "aggregated " : ""),
			   batadv_ogm_packet->orig,
			   ntohl(batadv_ogm_packet->seqno),
			   batadv_ogm_packet->tq, batadv_ogm_packet->ttl,
			   ((batadv_ogm_packet->flags & BATADV_DIRECTLINK) ?
			    "on" : "off"),
			   hard_iface->net_dev->name,
			   hard_iface->net_dev->dev_addr);

		buff_pos += BATADV_OGM_HLEN;
		buff_pos += ntohs(batadv_ogm_packet->tvlv_len);
		packet_num++;
		packet_pos = forw_packet->skb->data + buff_pos;
		batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
	}

	/* create clone because function is called more than once */
	skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
	if (skb) {
		batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_TX);
		batadv_add_counter(bat_priv, BATADV_CNT_MGMT_TX_BYTES,
				   skb->len + ETH_HLEN);
		batadv_send_broadcast_skb(skb, hard_iface);
	}
}

/* send a batman ogm packet */
static void batadv_iv_ogm_emit(struct batadv_forw_packet *forw_packet)
{
	struct net_device *soft_iface;
	struct batadv_priv *bat_priv;
	struct batadv_hard_iface *primary_if = NULL;

	if (!forw_packet->if_incoming) {
		pr_err("Error - can't forward packet: incoming iface not specified\n");
		goto out;
	}

	soft_iface = forw_packet->if_incoming->soft_iface;
	bat_priv = netdev_priv(soft_iface);

	if (WARN_ON(!forw_packet->if_outgoing))
		goto out;

	if (WARN_ON(forw_packet->if_outgoing->soft_iface != soft_iface))
		goto out;

	if (forw_packet->if_incoming->if_status != BATADV_IF_ACTIVE)
		goto out;

	primary_if = batadv_primary_if_get_selected(bat_priv);
	if (!primary_if)
		goto out;

	/* only for one specific outgoing interface */
	batadv_iv_ogm_send_to_if(forw_packet, forw_packet->if_outgoing);

out:
	if (primary_if)
		batadv_hardif_put(primary_if);
}

/**
 * batadv_iv_ogm_can_aggregate - find out if an OGM can be aggregated on an
 *  existing forward packet
 * @new_bat_ogm_packet: OGM packet to be aggregated
 * @bat_priv: the bat priv with all the soft interface information
 * @packet_len: (total) length of the OGM
 * @send_time: timestamp (jiffies) when the packet is to be sent
 * @directlink: true if this is a direct link packet
 * @if_incoming: interface where the packet was received
 * @if_outgoing: interface for which the retransmission should be considered
 * @forw_packet: the forwarded packet which should be checked
 *
 * Return: true if new_packet can be aggregated with forw_packet
 */
static bool
batadv_iv_ogm_can_aggregate(const struct batadv_ogm_packet *new_bat_ogm_packet,
			    struct batadv_priv *bat_priv,
			    int packet_len, unsigned long send_time,
			    bool directlink,
			    const struct batadv_hard_iface *if_incoming,
			    const struct batadv_hard_iface *if_outgoing,
			    const struct batadv_forw_packet *forw_packet)
{
	struct batadv_ogm_packet *batadv_ogm_packet;
	int aggregated_bytes = forw_packet->packet_len + packet_len;
	struct batadv_hard_iface *primary_if = NULL;
	bool res = false;
	unsigned long aggregation_end_time;

	batadv_ogm_packet = (struct batadv_ogm_packet *)forw_packet->skb->data;
	aggregation_end_time = send_time;
	aggregation_end_time += msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);

	/* we can aggregate the current packet to this aggregated packet
	 * if:
	 *
	 * - the send time is within our MAX_AGGREGATION_MS time
	 * - the resulting packet wont be bigger than
	 *   MAX_AGGREGATION_BYTES
	 * otherwise aggregation is not possible
	 */
	if (!time_before(send_time, forw_packet->send_time) ||
	    !time_after_eq(aggregation_end_time, forw_packet->send_time))
		return false;

	if (aggregated_bytes > BATADV_MAX_AGGREGATION_BYTES)
		return false;

	/* packet is not leaving on the same interface. */
	if (forw_packet->if_outgoing != if_outgoing)
		return false;

	/* check aggregation compatibility
	 * -> direct link packets are broadcasted on
	 *    their interface only
	 * -> aggregate packet if the current packet is
	 *    a "global" packet as well as the base
	 *    packet
	 */
	primary_if = batadv_primary_if_get_selected(bat_priv);
	if (!primary_if)
		return false;

	/* packets without direct link flag and high TTL
	 * are flooded through the net
	 */
	if (!directlink &&
	    !(batadv_ogm_packet->flags & BATADV_DIRECTLINK) &&
	    batadv_ogm_packet->ttl != 1 &&

	    /* own packets originating non-primary
	     * interfaces leave only that interface
	     */
	    (!forw_packet->own ||
	     forw_packet->if_incoming == primary_if)) {
		res = true;
		goto out;
	}

	/* if the incoming packet is sent via this one
	 * interface only - we still can aggregate
	 */
	if (directlink &&
	    new_bat_ogm_packet->ttl == 1 &&
	    forw_packet->if_incoming == if_incoming &&

	    /* packets from direct neighbors or
	     * own secondary interface packets
	     * (= secondary interface packets in general)
	     */
	    (batadv_ogm_packet->flags & BATADV_DIRECTLINK ||
	     (forw_packet->own &&
	      forw_packet->if_incoming != primary_if))) {
		res = true;
		goto out;
	}

out:
	if (primary_if)
		batadv_hardif_put(primary_if);
	return res;
}

/**
 * batadv_iv_ogm_aggregate_new - create a new aggregated packet and add this
 *  packet to it.
 * @packet_buff: pointer to the OGM
 * @packet_len: (total) length of the OGM
 * @send_time: timestamp (jiffies) when the packet is to be sent
 * @direct_link: whether this OGM has direct link status
 * @if_incoming: interface where the packet was received
 * @if_outgoing: interface for which the retransmission should be considered
 * @own_packet: true if it is a self-generated ogm
 */
static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
					int packet_len, unsigned long send_time,
					bool direct_link,
					struct batadv_hard_iface *if_incoming,
					struct batadv_hard_iface *if_outgoing,
					int own_packet)
{
	struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
	struct batadv_forw_packet *forw_packet_aggr;
	unsigned char *skb_buff;
	unsigned int skb_size;

	/* own packet should always be scheduled */
	if (!own_packet) {
		if (!batadv_atomic_dec_not_zero(&bat_priv->batman_queue_left)) {
			batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
				   "batman packet queue full\n");
			return;
		}
	}

	forw_packet_aggr = kmalloc(sizeof(*forw_packet_aggr), GFP_ATOMIC);
	if (!forw_packet_aggr)
		goto out_nomem;

	if (atomic_read(&bat_priv->aggregated_ogms) &&
	    packet_len < BATADV_MAX_AGGREGATION_BYTES)
		skb_size = BATADV_MAX_AGGREGATION_BYTES;
	else
		skb_size = packet_len;

	skb_size += ETH_HLEN;

	forw_packet_aggr->skb = netdev_alloc_skb_ip_align(NULL, skb_size);
	if (!forw_packet_aggr->skb)
		goto out_free_forw_packet;
	forw_packet_aggr->skb->priority = TC_PRIO_CONTROL;
	skb_reserve(forw_packet_aggr->skb, ETH_HLEN);

	skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
	forw_packet_aggr->packet_len = packet_len;
	memcpy(skb_buff, packet_buff, packet_len);

	kref_get(&if_incoming->refcount);
	kref_get(&if_outgoing->refcount);
	forw_packet_aggr->own = own_packet;
	forw_packet_aggr->if_incoming = if_incoming;
	forw_packet_aggr->if_outgoing = if_outgoing;
	forw_packet_aggr->num_packets = 0;
	forw_packet_aggr->direct_link_flags = BATADV_NO_FLAGS;
	forw_packet_aggr->send_time = send_time;

	/* save packet direct link flag status */
	if (direct_link)
		forw_packet_aggr->direct_link_flags |= 1;

	/* add new packet to packet list */
	spin_lock_bh(&bat_priv->forw_bat_list_lock);
	hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list);
	spin_unlock_bh(&bat_priv->forw_bat_list_lock);

	/* start timer for this packet */
	INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
			  batadv_iv_send_outstanding_bat_ogm_packet);
	queue_delayed_work(batadv_event_workqueue,
			   &forw_packet_aggr->delayed_work,
			   send_time - jiffies);

	return;
out_free_forw_packet:
	kfree(forw_packet_aggr);
out_nomem:
	if (!own_packet)
		atomic_inc(&bat_priv->batman_queue_left);
}

/* aggregate a new packet into the existing ogm packet */
static void batadv_iv_ogm_aggregate(struct batadv_forw_packet *forw_packet_aggr,
				    const unsigned char *packet_buff,
				    int packet_len, bool direct_link)
{
	unsigned char *skb_buff;
	unsigned long new_direct_link_flag;

	skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
	memcpy(skb_buff, packet_buff, packet_len);
	forw_packet_aggr->packet_len += packet_len;
	forw_packet_aggr->num_packets++;

	/* save packet direct link flag status */
	if (direct_link) {
		new_direct_link_flag = BIT(forw_packet_aggr->num_packets);
		forw_packet_aggr->direct_link_flags |= new_direct_link_flag;
	}
}

/**
 * batadv_iv_ogm_queue_add - queue up an OGM for transmission
 * @bat_priv: the bat priv with all the soft interface information
 * @packet_buff: pointer to the OGM
 * @packet_len: (total) length of the OGM
 * @if_incoming: interface where the packet was received
 * @if_outgoing: interface for which the retransmission should be considered
 * @own_packet: true if it is a self-generated ogm
 * @send_time: timestamp (jiffies) when the packet is to be sent
 */
static void batadv_iv_ogm_queue_add(struct batadv_priv *bat_priv,
				    unsigned char *packet_buff,
				    int packet_len,
				    struct batadv_hard_iface *if_incoming,
				    struct batadv_hard_iface *if_outgoing,
				    int own_packet, unsigned long send_time)
{
	/* _aggr -> pointer to the packet we want to aggregate with
	 * _pos -> pointer to the position in the queue
	 */
	struct batadv_forw_packet *forw_packet_aggr = NULL;
	struct batadv_forw_packet *forw_packet_pos = NULL;
	struct batadv_ogm_packet *batadv_ogm_packet;
	bool direct_link;
	unsigned long max_aggregation_jiffies;

	batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
	direct_link = !!(batadv_ogm_packet->flags & BATADV_DIRECTLINK);
	max_aggregation_jiffies = msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);

	/* find position for the packet in the forward queue */
	spin_lock_bh(&bat_priv->forw_bat_list_lock);
	/* own packets are not to be aggregated */
	if (atomic_read(&bat_priv->aggregated_ogms) && !own_packet) {
		hlist_for_each_entry(forw_packet_pos,
				     &bat_priv->forw_bat_list, list) {
			if (batadv_iv_ogm_can_aggregate(batadv_ogm_packet,
							bat_priv, packet_len,
							send_time, direct_link,
							if_incoming,
							if_outgoing,
							forw_packet_pos)) {
				forw_packet_aggr = forw_packet_pos;
				break;
			}
		}
	}

	/* nothing to aggregate with - either aggregation disabled or no
	 * suitable aggregation packet found
	 */
	if (!forw_packet_aggr) {
		/* the following section can run without the lock */
		spin_unlock_bh(&bat_priv->forw_bat_list_lock);

		/* if we could not aggregate this packet with one of the others
		 * we hold it back for a while, so that it might be aggregated
		 * later on
		 */
		if (!own_packet && atomic_read(&bat_priv->aggregated_ogms))
			send_time += max_aggregation_jiffies;

		batadv_iv_ogm_aggregate_new(packet_buff, packet_len,
					    send_time, direct_link,
					    if_incoming, if_outgoing,
					    own_packet);
	} else {
		batadv_iv_ogm_aggregate(forw_packet_aggr, packet_buff,
					packet_len, direct_link);
		spin_unlock_bh(&bat_priv->forw_bat_list_lock);
	}
}

static void batadv_iv_ogm_forward(struct batadv_orig_node *orig_node,
				  const struct ethhdr *ethhdr,
				  struct batadv_ogm_packet *batadv_ogm_packet,
				  bool is_single_hop_neigh,
				  bool is_from_best_next_hop,
				  struct batadv_hard_iface *if_incoming,
				  struct batadv_hard_iface *if_outgoing)
{
	struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
	u16 tvlv_len;

	if (batadv_ogm_packet->ttl <= 1) {
		batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n");
		return;
	}

	if (!is_from_best_next_hop) {
		/* Mark the forwarded packet when it is not coming from our
		 * best next hop. We still need to forward the packet for our
		 * neighbor link quality detection to work in case the packet
		 * originated from a single hop neighbor. Otherwise we can
		 * simply drop the ogm.
		 */
		if (is_single_hop_neigh)
			batadv_ogm_packet->flags |= BATADV_NOT_BEST_NEXT_HOP;
		else
			return;
	}

	tvlv_len = ntohs(batadv_ogm_packet->tvlv_len);

	batadv_ogm_packet->ttl--;
	ether_addr_copy(batadv_ogm_packet->prev_sender, ethhdr->h_source);

	/* apply hop penalty */
	batadv_ogm_packet->tq = batadv_hop_penalty(batadv_ogm_packet->tq,
						   bat_priv);

	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
		   "Forwarding packet: tq: %i, ttl: %i\n",
		   batadv_ogm_packet->tq, batadv_ogm_packet->ttl);

	if (is_single_hop_neigh)
		batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
	else
		batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;

	batadv_iv_ogm_queue_add(bat_priv, (unsigned char *)batadv_ogm_packet,
				BATADV_OGM_HLEN + tvlv_len,
				if_incoming, if_outgoing, 0,
				batadv_iv_ogm_fwd_send_time());
}

/**
 * batadv_iv_ogm_slide_own_bcast_window - bitshift own OGM broadcast windows for
 * the given interface
 * @hard_iface: the interface for which the windows have to be shifted
 */
static void
batadv_iv_ogm_slide_own_bcast_window(struct batadv_hard_iface *hard_iface)
{
	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
	struct batadv_hashtable *hash = bat_priv->orig_hash;
	struct hlist_head *head;
	struct batadv_orig_node *orig_node;
	unsigned long *word;
	u32 i;
	size_t word_index;
	u8 *w;
	int if_num;

	for (i = 0; i < hash->size; i++) {
		head = &hash->table[i];

		rcu_read_lock();
		hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
			spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
			word_index = hard_iface->if_num * BATADV_NUM_WORDS;
			word = &orig_node->bat_iv.bcast_own[word_index];

			batadv_bit_get_packet(bat_priv, word, 1, 0);
			if_num = hard_iface->if_num;
			w = &orig_node->bat_iv.bcast_own_sum[if_num];
			*w = bitmap_weight(word, BATADV_TQ_LOCAL_WINDOW_SIZE);
			spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
		}
		rcu_read_unlock();
	}
}

static void batadv_iv_ogm_schedule(struct batadv_hard_iface *hard_iface)
{
	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
	unsigned char **ogm_buff = &hard_iface->bat_iv.ogm_buff;
	struct batadv_ogm_packet *batadv_ogm_packet;
	struct batadv_hard_iface *primary_if, *tmp_hard_iface;
	int *ogm_buff_len = &hard_iface->bat_iv.ogm_buff_len;
	u32 seqno;
	u16 tvlv_len = 0;
	unsigned long send_time;

	if ((hard_iface->if_status == BATADV_IF_NOT_IN_USE) ||
	    (hard_iface->if_status == BATADV_IF_TO_BE_REMOVED))
		return;

	/* the interface gets activated here to avoid race conditions between
	 * the moment of activating the interface in
	 * hardif_activate_interface() where the originator mac is set and
	 * outdated packets (especially uninitialized mac addresses) in the
	 * packet queue
	 */
	if (hard_iface->if_status == BATADV_IF_TO_BE_ACTIVATED)
		hard_iface->if_status = BATADV_IF_ACTIVE;

	primary_if = batadv_primary_if_get_selected(bat_priv);

	if (hard_iface == primary_if) {
		/* tt changes have to be committed before the tvlv data is
		 * appended as it may alter the tt tvlv container
		 */
		batadv_tt_local_commit_changes(bat_priv);
		tvlv_len = batadv_tvlv_container_ogm_append(bat_priv, ogm_buff,
							    ogm_buff_len,
							    BATADV_OGM_HLEN);
	}

	batadv_ogm_packet = (struct batadv_ogm_packet *)(*ogm_buff);
	batadv_ogm_packet->tvlv_len = htons(tvlv_len);

	/* change sequence number to network order */
	seqno = (u32)atomic_read(&hard_iface->bat_iv.ogm_seqno);
	batadv_ogm_packet->seqno = htonl(seqno);
	atomic_inc(&hard_iface->bat_iv.ogm_seqno);

	batadv_iv_ogm_slide_own_bcast_window(hard_iface);

	send_time = batadv_iv_ogm_emit_send_time(bat_priv);

	if (hard_iface != primary_if) {
		/* OGMs from secondary interfaces are only scheduled on their
		 * respective interfaces.
		 */
		batadv_iv_ogm_queue_add(bat_priv, *ogm_buff, *ogm_buff_len,
					hard_iface, hard_iface, 1, send_time);
		goto out;
	}

	/* OGMs from primary interfaces are scheduled on all
	 * interfaces.
	 */
	rcu_read_lock();
	list_for_each_entry_rcu(tmp_hard_iface, &batadv_hardif_list, list) {
		if (tmp_hard_iface->soft_iface != hard_iface->soft_iface)
			continue;

		if (!kref_get_unless_zero(&tmp_hard_iface->refcount))
			continue;

		batadv_iv_ogm_queue_add(bat_priv, *ogm_buff,
					*ogm_buff_len, hard_iface,
					tmp_hard_iface, 1, send_time);

		batadv_hardif_put(tmp_hard_iface);
	}
	rcu_read_unlock();

out:
	if (primary_if)
		batadv_hardif_put(primary_if);
}

/**
 * batadv_iv_ogm_orig_update - use OGM to update corresponding data in an
 *  originator
 * @bat_priv: the bat priv with all the soft interface information
 * @orig_node: the orig node who originally emitted the ogm packet
 * @orig_ifinfo: ifinfo for the outgoing interface of the orig_node
 * @ethhdr: Ethernet header of the OGM
 * @batadv_ogm_packet: the ogm packet
 * @if_incoming: interface where the packet was received
 * @if_outgoing: interface for which the retransmission should be considered
 * @dup_status: the duplicate status of this ogm packet.
 */
static void
batadv_iv_ogm_orig_update(struct batadv_priv *bat_priv,
			  struct batadv_orig_node *orig_node,
			  struct batadv_orig_ifinfo *orig_ifinfo,
			  const struct ethhdr *ethhdr,
			  const struct batadv_ogm_packet *batadv_ogm_packet,
			  struct batadv_hard_iface *if_incoming,
			  struct batadv_hard_iface *if_outgoing,
			  enum batadv_dup_status dup_status)
{
	struct batadv_neigh_ifinfo *neigh_ifinfo = NULL;
	struct batadv_neigh_ifinfo *router_ifinfo = NULL;
	struct batadv_neigh_node *neigh_node = NULL;
	struct batadv_neigh_node *tmp_neigh_node = NULL;
	struct batadv_neigh_node *router = NULL;
	struct batadv_orig_node *orig_node_tmp;
	int if_num;
	u8 sum_orig, sum_neigh;
	u8 *neigh_addr;
	u8 tq_avg;

	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
		   "update_originator(): Searching and updating originator entry of received packet\n");

	rcu_read_lock();
	hlist_for_each_entry_rcu(tmp_neigh_node,
				 &orig_node->neigh_list, list) {
		neigh_addr = tmp_neigh_node->addr;
		if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
		    tmp_neigh_node->if_incoming == if_incoming &&
		    kref_get_unless_zero(&tmp_neigh_node->refcount)) {
			if (WARN(neigh_node, "too many matching neigh_nodes"))
				batadv_neigh_node_put(neigh_node);
			neigh_node = tmp_neigh_node;
			continue;
		}

		if (dup_status != BATADV_NO_DUP)
			continue;

		/* only update the entry for this outgoing interface */
		neigh_ifinfo = batadv_neigh_ifinfo_get(tmp_neigh_node,
						       if_outgoing);
		if (!neigh_ifinfo)
			continue;

		spin_lock_bh(&tmp_neigh_node->ifinfo_lock);
		batadv_ring_buffer_set(neigh_ifinfo->bat_iv.tq_recv,
				       &neigh_ifinfo->bat_iv.tq_index, 0);
		tq_avg = batadv_ring_buffer_avg(neigh_ifinfo->bat_iv.tq_recv);
		neigh_ifinfo->bat_iv.tq_avg = tq_avg;
		spin_unlock_bh(&tmp_neigh_node->ifinfo_lock);

		batadv_neigh_ifinfo_put(neigh_ifinfo);
		neigh_ifinfo = NULL;
	}

	if (!neigh_node) {
		struct batadv_orig_node *orig_tmp;

		orig_tmp = batadv_iv_ogm_orig_get(bat_priv, ethhdr->h_source);
		if (!orig_tmp)
			goto unlock;

		neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
						     ethhdr->h_source,
						     orig_node, orig_tmp);

		batadv_orig_node_put(orig_tmp);
		if (!neigh_node)
			goto unlock;
	} else {
		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "Updating existing last-hop neighbor of originator\n");
	}

	rcu_read_unlock();
	neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node, if_outgoing);
	if (!neigh_ifinfo)
		goto out;

	neigh_node->last_seen = jiffies;

	spin_lock_bh(&neigh_node->ifinfo_lock);
	batadv_ring_buffer_set(neigh_ifinfo->bat_iv.tq_recv,
			       &neigh_ifinfo->bat_iv.tq_index,
			       batadv_ogm_packet->tq);
	tq_avg = batadv_ring_buffer_avg(neigh_ifinfo->bat_iv.tq_recv);
	neigh_ifinfo->bat_iv.tq_avg = tq_avg;
	spin_unlock_bh(&neigh_node->ifinfo_lock);

	if (dup_status == BATADV_NO_DUP) {
		orig_ifinfo->last_ttl = batadv_ogm_packet->ttl;
		neigh_ifinfo->last_ttl = batadv_ogm_packet->ttl;
	}

	/* if this neighbor already is our next hop there is nothing
	 * to change
	 */
	router = batadv_orig_router_get(orig_node, if_outgoing);
	if (router == neigh_node)
		goto out;

	if (router) {
		router_ifinfo = batadv_neigh_ifinfo_get(router, if_outgoing);
		if (!router_ifinfo)
			goto out;

		/* if this neighbor does not offer a better TQ we won't
		 * consider it
		 */
		if (router_ifinfo->bat_iv.tq_avg > neigh_ifinfo->bat_iv.tq_avg)
			goto out;
	}

	/* if the TQ is the same and the link not more symmetric we
	 * won't consider it either
	 */
	if (router_ifinfo &&
	    neigh_ifinfo->bat_iv.tq_avg == router_ifinfo->bat_iv.tq_avg) {
		orig_node_tmp = router->orig_node;
		spin_lock_bh(&orig_node_tmp->bat_iv.ogm_cnt_lock);
		if_num = router->if_incoming->if_num;
		sum_orig = orig_node_tmp->bat_iv.bcast_own_sum[if_num];
		spin_unlock_bh(&orig_node_tmp->bat_iv.ogm_cnt_lock);

		orig_node_tmp = neigh_node->orig_node;
		spin_lock_bh(&orig_node_tmp->bat_iv.ogm_cnt_lock);
		if_num = neigh_node->if_incoming->if_num;
		sum_neigh = orig_node_tmp->bat_iv.bcast_own_sum[if_num];
		spin_unlock_bh(&orig_node_tmp->bat_iv.ogm_cnt_lock);

		if (sum_orig >= sum_neigh)
			goto out;
	}

	batadv_update_route(bat_priv, orig_node, if_outgoing, neigh_node);
	goto out;

unlock:
	rcu_read_unlock();
out:
	if (neigh_node)
		batadv_neigh_node_put(neigh_node);
	if (router)
		batadv_neigh_node_put(router);
	if (neigh_ifinfo)
		batadv_neigh_ifinfo_put(neigh_ifinfo);
	if (router_ifinfo)
		batadv_neigh_ifinfo_put(router_ifinfo);
}

/**
 * batadv_iv_ogm_calc_tq - calculate tq for current received ogm packet
 * @orig_node: the orig node who originally emitted the ogm packet
 * @orig_neigh_node: the orig node struct of the neighbor who sent the packet
 * @batadv_ogm_packet: the ogm packet
 * @if_incoming: interface where the packet was received
 * @if_outgoing: interface for which the retransmission should be considered
 *
 * Return: true if the link can be considered bidirectional, false otherwise
 */
static bool batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node,
				  struct batadv_orig_node *orig_neigh_node,
				  struct batadv_ogm_packet *batadv_ogm_packet,
				  struct batadv_hard_iface *if_incoming,
				  struct batadv_hard_iface *if_outgoing)
{
	struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
	struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node;
	struct batadv_neigh_ifinfo *neigh_ifinfo;
	u8 total_count;
	u8 orig_eq_count, neigh_rq_count, neigh_rq_inv, tq_own;
	unsigned int neigh_rq_inv_cube, neigh_rq_max_cube;
	int if_num;
	unsigned int tq_asym_penalty, inv_asym_penalty;
	unsigned int combined_tq;
	unsigned int tq_iface_penalty;
	bool ret = false;

	/* find corresponding one hop neighbor */
	rcu_read_lock();
	hlist_for_each_entry_rcu(tmp_neigh_node,
				 &orig_neigh_node->neigh_list, list) {
		if (!batadv_compare_eth(tmp_neigh_node->addr,
					orig_neigh_node->orig))
			continue;

		if (tmp_neigh_node->if_incoming != if_incoming)
			continue;

		if (!kref_get_unless_zero(&tmp_neigh_node->refcount))
			continue;

		neigh_node = tmp_neigh_node;
		break;
	}
	rcu_read_unlock();

	if (!neigh_node)
		neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
						     orig_neigh_node->orig,
						     orig_neigh_node,
						     orig_neigh_node);

	if (!neigh_node)
		goto out;

	/* if orig_node is direct neighbor update neigh_node last_seen */
	if (orig_node == orig_neigh_node)
		neigh_node->last_seen = jiffies;

	orig_node->last_seen = jiffies;

	/* find packet count of corresponding one hop neighbor */
	spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
	if_num = if_incoming->if_num;
	orig_eq_count = orig_neigh_node->bat_iv.bcast_own_sum[if_num];
	neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node, if_outgoing);
	if (neigh_ifinfo) {
		neigh_rq_count = neigh_ifinfo->bat_iv.real_packet_count;
		batadv_neigh_ifinfo_put(neigh_ifinfo);
	} else {
		neigh_rq_count = 0;
	}
	spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);

	/* pay attention to not get a value bigger than 100 % */
	if (orig_eq_count > neigh_rq_count)
		total_count = neigh_rq_count;
	else
		total_count = orig_eq_count;

	/* if we have too few packets (too less data) we set tq_own to zero
	 * if we receive too few packets it is not considered bidirectional
	 */
	if (total_count < BATADV_TQ_LOCAL_BIDRECT_SEND_MINIMUM ||
	    neigh_rq_count < BATADV_TQ_LOCAL_BIDRECT_RECV_MINIMUM)
		tq_own = 0;
	else
		/* neigh_node->real_packet_count is never zero as we
		 * only purge old information when getting new
		 * information
		 */
		tq_own = (BATADV_TQ_MAX_VALUE * total_count) /	neigh_rq_count;

	/* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
	 * affect the nearly-symmetric links only a little, but
	 * punishes asymmetric links more.  This will give a value
	 * between 0 and TQ_MAX_VALUE
	 */
	neigh_rq_inv = BATADV_TQ_LOCAL_WINDOW_SIZE - neigh_rq_count;
	neigh_rq_inv_cube = neigh_rq_inv * neigh_rq_inv * neigh_rq_inv;
	neigh_rq_max_cube = BATADV_TQ_LOCAL_WINDOW_SIZE *
			    BATADV_TQ_LOCAL_WINDOW_SIZE *
			    BATADV_TQ_LOCAL_WINDOW_SIZE;
	inv_asym_penalty = BATADV_TQ_MAX_VALUE * neigh_rq_inv_cube;
	inv_asym_penalty /= neigh_rq_max_cube;
	tq_asym_penalty = BATADV_TQ_MAX_VALUE - inv_asym_penalty;

	/* penalize if the OGM is forwarded on the same interface. WiFi
	 * interfaces and other half duplex devices suffer from throughput
	 * drops as they can't send and receive at the same time.
	 */
	tq_iface_penalty = BATADV_TQ_MAX_VALUE;
	if (if_outgoing && (if_incoming == if_outgoing) &&
	    batadv_is_wifi_netdev(if_outgoing->net_dev))
		tq_iface_penalty = batadv_hop_penalty(BATADV_TQ_MAX_VALUE,
						      bat_priv);

	combined_tq = batadv_ogm_packet->tq *
		      tq_own *
		      tq_asym_penalty *
		      tq_iface_penalty;
	combined_tq /= BATADV_TQ_MAX_VALUE *
		       BATADV_TQ_MAX_VALUE *
		       BATADV_TQ_MAX_VALUE;
	batadv_ogm_packet->tq = combined_tq;

	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
		   "bidirectional: orig = %-15pM neigh = %-15pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, iface_penalty: %3i, total tq: %3i, if_incoming = %s, if_outgoing = %s\n",
		   orig_node->orig, orig_neigh_node->orig, total_count,
		   neigh_rq_count, tq_own, tq_asym_penalty, tq_iface_penalty,
		   batadv_ogm_packet->tq, if_incoming->net_dev->name,
		   if_outgoing ? if_outgoing->net_dev->name : "DEFAULT");

	/* if link has the minimum required transmission quality
	 * consider it bidirectional
	 */
	if (batadv_ogm_packet->tq >= BATADV_TQ_TOTAL_BIDRECT_LIMIT)
		ret = true;

out:
	if (neigh_node)
		batadv_neigh_node_put(neigh_node);
	return ret;
}

/**
 * batadv_iv_ogm_update_seqnos -  process a batman packet for all interfaces,
 *  adjust the sequence number and find out whether it is a duplicate
 * @ethhdr: ethernet header of the packet
 * @batadv_ogm_packet: OGM packet to be considered
 * @if_incoming: interface on which the OGM packet was received
 * @if_outgoing: interface for which the retransmission should be considered
 *
 * Return: duplicate status as enum batadv_dup_status
 */
static enum batadv_dup_status
batadv_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
			    const struct batadv_ogm_packet *batadv_ogm_packet,
			    const struct batadv_hard_iface *if_incoming,
			    struct batadv_hard_iface *if_outgoing)
{
	struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
	struct batadv_orig_node *orig_node;
	struct batadv_orig_ifinfo *orig_ifinfo = NULL;
	struct batadv_neigh_node *neigh_node;
	struct batadv_neigh_ifinfo *neigh_ifinfo;
	bool is_dup;
	s32 seq_diff;
	bool need_update = false;
	int set_mark;
	enum batadv_dup_status ret = BATADV_NO_DUP;
	u32 seqno = ntohl(batadv_ogm_packet->seqno);
	u8 *neigh_addr;
	u8 packet_count;
	unsigned long *bitmap;

	orig_node = batadv_iv_ogm_orig_get(bat_priv, batadv_ogm_packet->orig);
	if (!orig_node)
		return BATADV_NO_DUP;

	orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing);
	if (WARN_ON(!orig_ifinfo)) {
		batadv_orig_node_put(orig_node);
		return 0;
	}

	spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
	seq_diff = seqno - orig_ifinfo->last_real_seqno;

	/* signalize caller that the packet is to be dropped. */
	if (!hlist_empty(&orig_node->neigh_list) &&
	    batadv_window_protected(bat_priv, seq_diff,
				    BATADV_TQ_LOCAL_WINDOW_SIZE,
				    &orig_ifinfo->batman_seqno_reset, NULL)) {
		ret = BATADV_PROTECTED;
		goto out;
	}

	rcu_read_lock();
	hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
		neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node,
						       if_outgoing);
		if (!neigh_ifinfo)
			continue;

		neigh_addr = neigh_node->addr;
		is_dup = batadv_test_bit(neigh_ifinfo->bat_iv.real_bits,
					 orig_ifinfo->last_real_seqno,
					 seqno);

		if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
		    neigh_node->if_incoming == if_incoming) {
			set_mark = 1;
			if (is_dup)
				ret = BATADV_NEIGH_DUP;
		} else {
			set_mark = 0;
			if (is_dup && (ret != BATADV_NEIGH_DUP))
				ret = BATADV_ORIG_DUP;
		}

		/* if the window moved, set the update flag. */
		bitmap = neigh_ifinfo->bat_iv.real_bits;
		need_update |= batadv_bit_get_packet(bat_priv, bitmap,
						     seq_diff, set_mark);

		packet_count = bitmap_weight(bitmap,
					     BATADV_TQ_LOCAL_WINDOW_SIZE);
		neigh_ifinfo->bat_iv.real_packet_count = packet_count;
		batadv_neigh_ifinfo_put(neigh_ifinfo);
	}
	rcu_read_unlock();

	if (need_update) {
		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "%s updating last_seqno: old %u, new %u\n",
			   if_outgoing ? if_outgoing->net_dev->name : "DEFAULT",
			   orig_ifinfo->last_real_seqno, seqno);
		orig_ifinfo->last_real_seqno = seqno;
	}

out:
	spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
	batadv_orig_node_put(orig_node);
	batadv_orig_ifinfo_put(orig_ifinfo);
	return ret;
}

/**
 * batadv_iv_ogm_process_per_outif - process a batman iv OGM for an outgoing if
 * @skb: the skb containing the OGM
 * @ogm_offset: offset from skb->data to start of ogm header
 * @orig_node: the (cached) orig node for the originator of this OGM
 * @if_incoming: the interface where this packet was received
 * @if_outgoing: the interface for which the packet should be considered
 */
static void
batadv_iv_ogm_process_per_outif(const struct sk_buff *skb, int ogm_offset,
				struct batadv_orig_node *orig_node,
				struct batadv_hard_iface *if_incoming,
				struct batadv_hard_iface *if_outgoing)
{
	struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
	struct batadv_hardif_neigh_node *hardif_neigh = NULL;
	struct batadv_neigh_node *router = NULL;
	struct batadv_neigh_node *router_router = NULL;
	struct batadv_orig_node *orig_neigh_node;
	struct batadv_orig_ifinfo *orig_ifinfo;
	struct batadv_neigh_node *orig_neigh_router = NULL;
	struct batadv_neigh_ifinfo *router_ifinfo = NULL;
	struct batadv_ogm_packet *ogm_packet;
	enum batadv_dup_status dup_status;
	bool is_from_best_next_hop = false;
	bool is_single_hop_neigh = false;
	bool sameseq, similar_ttl;
	struct sk_buff *skb_priv;
	struct ethhdr *ethhdr;
	u8 *prev_sender;
	bool is_bidirect;

	/* create a private copy of the skb, as some functions change tq value
	 * and/or flags.
	 */
	skb_priv = skb_copy(skb, GFP_ATOMIC);
	if (!skb_priv)
		return;

	ethhdr = eth_hdr(skb_priv);
	ogm_packet = (struct batadv_ogm_packet *)(skb_priv->data + ogm_offset);

	dup_status = batadv_iv_ogm_update_seqnos(ethhdr, ogm_packet,
						 if_incoming, if_outgoing);
	if (batadv_compare_eth(ethhdr->h_source, ogm_packet->orig))
		is_single_hop_neigh = true;

	if (dup_status == BATADV_PROTECTED) {
		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "Drop packet: packet within seqno protection time (sender: %pM)\n",
			   ethhdr->h_source);
		goto out;
	}

	if (ogm_packet->tq == 0) {
		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "Drop packet: originator packet with tq equal 0\n");
		goto out;
	}

	if (is_single_hop_neigh) {
		hardif_neigh = batadv_hardif_neigh_get(if_incoming,
						       ethhdr->h_source);
		if (hardif_neigh)
			hardif_neigh->last_seen = jiffies;
	}

	router = batadv_orig_router_get(orig_node, if_outgoing);
	if (router) {
		router_router = batadv_orig_router_get(router->orig_node,
						       if_outgoing);
		router_ifinfo = batadv_neigh_ifinfo_get(router, if_outgoing);
	}

	if ((router_ifinfo && router_ifinfo->bat_iv.tq_avg != 0) &&
	    (batadv_compare_eth(router->addr, ethhdr->h_source)))
		is_from_best_next_hop = true;

	prev_sender = ogm_packet->prev_sender;
	/* avoid temporary routing loops */
	if (router && router_router &&
	    (batadv_compare_eth(router->addr, prev_sender)) &&
	    !(batadv_compare_eth(ogm_packet->orig, prev_sender)) &&
	    (batadv_compare_eth(router->addr, router_router->addr))) {
		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n",
			   ethhdr->h_source);
		goto out;
	}

	if (if_outgoing == BATADV_IF_DEFAULT)
		batadv_tvlv_ogm_receive(bat_priv, ogm_packet, orig_node);

	/* if sender is a direct neighbor the sender mac equals
	 * originator mac
	 */
	if (is_single_hop_neigh)
		orig_neigh_node = orig_node;
	else
		orig_neigh_node = batadv_iv_ogm_orig_get(bat_priv,
							 ethhdr->h_source);

	if (!orig_neigh_node)
		goto out;

	/* Update nc_nodes of the originator */
	batadv_nc_update_nc_node(bat_priv, orig_node, orig_neigh_node,
				 ogm_packet, is_single_hop_neigh);

	orig_neigh_router = batadv_orig_router_get(orig_neigh_node,
						   if_outgoing);

	/* drop packet if sender is not a direct neighbor and if we
	 * don't route towards it
	 */
	if (!is_single_hop_neigh && (!orig_neigh_router)) {
		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "Drop packet: OGM via unknown neighbor!\n");
		goto out_neigh;
	}

	is_bidirect = batadv_iv_ogm_calc_tq(orig_node, orig_neigh_node,
					    ogm_packet, if_incoming,
					    if_outgoing);

	/* update ranking if it is not a duplicate or has the same
	 * seqno and similar ttl as the non-duplicate
	 */
	orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing);
	if (!orig_ifinfo)
		goto out_neigh;

	sameseq = orig_ifinfo->last_real_seqno == ntohl(ogm_packet->seqno);
	similar_ttl = (orig_ifinfo->last_ttl - 3) <= ogm_packet->ttl;

	if (is_bidirect && ((dup_status == BATADV_NO_DUP) ||
			    (sameseq && similar_ttl))) {
		batadv_iv_ogm_orig_update(bat_priv, orig_node,
					  orig_ifinfo, ethhdr,
					  ogm_packet, if_incoming,
					  if_outgoing, dup_status);
	}
	batadv_orig_ifinfo_put(orig_ifinfo);

	/* only forward for specific interface, not for the default one. */
	if (if_outgoing == BATADV_IF_DEFAULT)
		goto out_neigh;

	/* is single hop (direct) neighbor */
	if (is_single_hop_neigh) {
		/* OGMs from secondary interfaces should only scheduled once
		 * per interface where it has been received, not multiple times
		 */
		if ((ogm_packet->ttl <= 2) &&
		    (if_incoming != if_outgoing)) {
			batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
				   "Drop packet: OGM from secondary interface and wrong outgoing interface\n");
			goto out_neigh;
		}
		/* mark direct link on incoming interface */
		batadv_iv_ogm_forward(orig_node, ethhdr, ogm_packet,
				      is_single_hop_neigh,
				      is_from_best_next_hop, if_incoming,
				      if_outgoing);

		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
		goto out_neigh;
	}

	/* multihop originator */
	if (!is_bidirect) {
		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "Drop packet: not received via bidirectional link\n");
		goto out_neigh;
	}

	if (dup_status == BATADV_NEIGH_DUP) {
		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "Drop packet: duplicate packet received\n");
		goto out_neigh;
	}

	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
		   "Forwarding packet: rebroadcast originator packet\n");
	batadv_iv_ogm_forward(orig_node, ethhdr, ogm_packet,
			      is_single_hop_neigh, is_from_best_next_hop,
			      if_incoming, if_outgoing);

out_neigh:
	if ((orig_neigh_node) && (!is_single_hop_neigh))
		batadv_orig_node_put(orig_neigh_node);
out:
	if (router_ifinfo)
		batadv_neigh_ifinfo_put(router_ifinfo);
	if (router)
		batadv_neigh_node_put(router);
	if (router_router)
		batadv_neigh_node_put(router_router);
	if (orig_neigh_router)
		batadv_neigh_node_put(orig_neigh_router);
	if (hardif_neigh)
		batadv_hardif_neigh_put(hardif_neigh);

	kfree_skb(skb_priv);
}

/**
 * batadv_iv_ogm_process - process an incoming batman iv OGM
 * @skb: the skb containing the OGM
 * @ogm_offset: offset to the OGM which should be processed (for aggregates)
 * @if_incoming: the interface where this packet was receved
 */
static void batadv_iv_ogm_process(const struct sk_buff *skb, int ogm_offset,
				  struct batadv_hard_iface *if_incoming)
{
	struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
	struct batadv_orig_node *orig_neigh_node, *orig_node;
	struct batadv_hard_iface *hard_iface;
	struct batadv_ogm_packet *ogm_packet;
	u32 if_incoming_seqno;
	bool has_directlink_flag;
	struct ethhdr *ethhdr;
	bool is_my_oldorig = false;
	bool is_my_addr = false;
	bool is_my_orig = false;

	ogm_packet = (struct batadv_ogm_packet *)(skb->data + ogm_offset);
	ethhdr = eth_hdr(skb);

	/* Silently drop when the batman packet is actually not a
	 * correct packet.
	 *
	 * This might happen if a packet is padded (e.g. Ethernet has a
	 * minimum frame length of 64 byte) and the aggregation interprets
	 * it as an additional length.
	 *
	 * TODO: A more sane solution would be to have a bit in the
	 * batadv_ogm_packet to detect whether the packet is the last
	 * packet in an aggregation.  Here we expect that the padding
	 * is always zero (or not 0x01)
	 */
	if (ogm_packet->packet_type != BATADV_IV_OGM)
		return;

	/* could be changed by schedule_own_packet() */
	if_incoming_seqno = atomic_read(&if_incoming->bat_iv.ogm_seqno);

	if (ogm_packet->flags & BATADV_DIRECTLINK)
		has_directlink_flag = true;
	else
		has_directlink_flag = false;

	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
		   "Received BATMAN packet via NB: %pM, IF: %s [%pM] (from OG: %pM, via prev OG: %pM, seqno %u, tq %d, TTL %d, V %d, IDF %d)\n",
		   ethhdr->h_source, if_incoming->net_dev->name,
		   if_incoming->net_dev->dev_addr, ogm_packet->orig,
		   ogm_packet->prev_sender, ntohl(ogm_packet->seqno),
		   ogm_packet->tq, ogm_packet->ttl,
		   ogm_packet->version, has_directlink_flag);

	rcu_read_lock();
	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
		if (hard_iface->if_status != BATADV_IF_ACTIVE)
			continue;

		if (hard_iface->soft_iface != if_incoming->soft_iface)
			continue;

		if (batadv_compare_eth(ethhdr->h_source,
				       hard_iface->net_dev->dev_addr))
			is_my_addr = true;

		if (batadv_compare_eth(ogm_packet->orig,
				       hard_iface->net_dev->dev_addr))
			is_my_orig = true;

		if (batadv_compare_eth(ogm_packet->prev_sender,
				       hard_iface->net_dev->dev_addr))
			is_my_oldorig = true;
	}
	rcu_read_unlock();

	if (is_my_addr) {
		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "Drop packet: received my own broadcast (sender: %pM)\n",
			   ethhdr->h_source);
		return;
	}

	if (is_my_orig) {
		unsigned long *word;
		int offset;
		s32 bit_pos;
		s16 if_num;
		u8 *weight;

		orig_neigh_node = batadv_iv_ogm_orig_get(bat_priv,
							 ethhdr->h_source);
		if (!orig_neigh_node)
			return;

		/* neighbor has to indicate direct link and it has to
		 * come via the corresponding interface
		 * save packet seqno for bidirectional check
		 */
		if (has_directlink_flag &&
		    batadv_compare_eth(if_incoming->net_dev->dev_addr,
				       ogm_packet->orig)) {
			if_num = if_incoming->if_num;
			offset = if_num * BATADV_NUM_WORDS;

			spin_lock_bh(&orig_neigh_node->bat_iv.ogm_cnt_lock);
			word = &orig_neigh_node->bat_iv.bcast_own[offset];
			bit_pos = if_incoming_seqno - 2;
			bit_pos -= ntohl(ogm_packet->seqno);
			batadv_set_bit(word, bit_pos);
			weight = &orig_neigh_node->bat_iv.bcast_own_sum[if_num];
			*weight = bitmap_weight(word,
						BATADV_TQ_LOCAL_WINDOW_SIZE);
			spin_unlock_bh(&orig_neigh_node->bat_iv.ogm_cnt_lock);
		}

		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "Drop packet: originator packet from myself (via neighbor)\n");
		batadv_orig_node_put(orig_neigh_node);
		return;
	}

	if (is_my_oldorig) {
		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n",
			   ethhdr->h_source);
		return;
	}

	if (ogm_packet->flags & BATADV_NOT_BEST_NEXT_HOP) {
		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "Drop packet: ignoring all packets not forwarded from the best next hop (sender: %pM)\n",
			   ethhdr->h_source);
		return;
	}

	orig_node = batadv_iv_ogm_orig_get(bat_priv, ogm_packet->orig);
	if (!orig_node)
		return;

	batadv_iv_ogm_process_per_outif(skb, ogm_offset, orig_node,
					if_incoming, BATADV_IF_DEFAULT);

	rcu_read_lock();
	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
		if (hard_iface->if_status != BATADV_IF_ACTIVE)
			continue;

		if (hard_iface->soft_iface != bat_priv->soft_iface)
			continue;

		if (!kref_get_unless_zero(&hard_iface->refcount))
			continue;

		batadv_iv_ogm_process_per_outif(skb, ogm_offset, orig_node,
						if_incoming, hard_iface);

		batadv_hardif_put(hard_iface);
	}
	rcu_read_unlock();

	batadv_orig_node_put(orig_node);
}

static void batadv_iv_send_outstanding_bat_ogm_packet(struct work_struct *work)
{
	struct delayed_work *delayed_work;
	struct batadv_forw_packet *forw_packet;
	struct batadv_priv *bat_priv;

	delayed_work = to_delayed_work(work);
	forw_packet = container_of(delayed_work, struct batadv_forw_packet,
				   delayed_work);
	bat_priv = netdev_priv(forw_packet->if_incoming->soft_iface);
	spin_lock_bh(&bat_priv->forw_bat_list_lock);
	hlist_del(&forw_packet->list);
	spin_unlock_bh(&bat_priv->forw_bat_list_lock);

	if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING)
		goto out;

	batadv_iv_ogm_emit(forw_packet);

	/* we have to have at least one packet in the queue to determine the
	 * queues wake up time unless we are shutting down.
	 *
	 * only re-schedule if this is the "original" copy, e.g. the OGM of the
	 * primary interface should only be rescheduled once per period, but
	 * this function will be called for the forw_packet instances of the
	 * other secondary interfaces as well.
	 */
	if (forw_packet->own &&
	    forw_packet->if_incoming == forw_packet->if_outgoing)
		batadv_iv_ogm_schedule(forw_packet->if_incoming);

out:
	/* don't count own packet */
	if (!forw_packet->own)
		atomic_inc(&bat_priv->batman_queue_left);

	batadv_forw_packet_free(forw_packet);
}

static int batadv_iv_ogm_receive(struct sk_buff *skb,
				 struct batadv_hard_iface *if_incoming)
{
	struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
	struct batadv_ogm_packet *ogm_packet;
	u8 *packet_pos;
	int ogm_offset;
	bool ret;

	ret = batadv_check_management_packet(skb, if_incoming, BATADV_OGM_HLEN);
	if (!ret)
		return NET_RX_DROP;

	/* did we receive a B.A.T.M.A.N. IV OGM packet on an interface
	 * that does not have B.A.T.M.A.N. IV enabled ?
	 */
	if (bat_priv->bat_algo_ops->bat_iface_enable !=
	    batadv_iv_ogm_iface_enable)
		return NET_RX_DROP;

	batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX);
	batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES,
			   skb->len + ETH_HLEN);

	ogm_offset = 0;
	ogm_packet = (struct batadv_ogm_packet *)skb->data;

	/* unpack the aggregated packets and process them one by one */
	while (batadv_iv_ogm_aggr_packet(ogm_offset, skb_headlen(skb),
					 ogm_packet->tvlv_len)) {
		batadv_iv_ogm_process(skb, ogm_offset, if_incoming);

		ogm_offset += BATADV_OGM_HLEN;
		ogm_offset += ntohs(ogm_packet->tvlv_len);

		packet_pos = skb->data + ogm_offset;
		ogm_packet = (struct batadv_ogm_packet *)packet_pos;
	}

	kfree_skb(skb);
	return NET_RX_SUCCESS;
}

/**
 * batadv_iv_ogm_orig_print_neigh - print neighbors for the originator table
 * @orig_node: the orig_node for which the neighbors are printed
 * @if_outgoing: outgoing interface for these entries
 * @seq: debugfs table seq_file struct
 *
 * Must be called while holding an rcu lock.
 */
static void
batadv_iv_ogm_orig_print_neigh(struct batadv_orig_node *orig_node,
			       struct batadv_hard_iface *if_outgoing,
			       struct seq_file *seq)
{
	struct batadv_neigh_node *neigh_node;
	struct batadv_neigh_ifinfo *n_ifinfo;

	hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
		n_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
		if (!n_ifinfo)
			continue;

		seq_printf(seq, " %pM (%3i)",
			   neigh_node->addr,
			   n_ifinfo->bat_iv.tq_avg);

		batadv_neigh_ifinfo_put(n_ifinfo);
	}
}

/**
 * batadv_iv_ogm_orig_print - print the originator table
 * @bat_priv: the bat priv with all the soft interface information
 * @seq: debugfs table seq_file struct
 * @if_outgoing: the outgoing interface for which this should be printed
 */
static void batadv_iv_ogm_orig_print(struct batadv_priv *bat_priv,
				     struct seq_file *seq,
				     struct batadv_hard_iface *if_outgoing)
{
	struct batadv_neigh_node *neigh_node;
	struct batadv_hashtable *hash = bat_priv->orig_hash;
	int last_seen_msecs, last_seen_secs;
	struct batadv_orig_node *orig_node;
	struct batadv_neigh_ifinfo *n_ifinfo;
	unsigned long last_seen_jiffies;
	struct hlist_head *head;
	int batman_count = 0;
	u32 i;

	seq_puts(seq,
		 "  Originator      last-seen (#/255)           Nexthop [outgoingIF]:   Potential nexthops ...\n");

	for (i = 0; i < hash->size; i++) {
		head = &hash->table[i];

		rcu_read_lock();
		hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
			neigh_node = batadv_orig_router_get(orig_node,
							    if_outgoing);
			if (!neigh_node)
				continue;

			n_ifinfo = batadv_neigh_ifinfo_get(neigh_node,
							   if_outgoing);
			if (!n_ifinfo)
				goto next;

			if (n_ifinfo->bat_iv.tq_avg == 0)
				goto next;

			last_seen_jiffies = jiffies - orig_node->last_seen;
			last_seen_msecs = jiffies_to_msecs(last_seen_jiffies);
			last_seen_secs = last_seen_msecs / 1000;
			last_seen_msecs = last_seen_msecs % 1000;

			seq_printf(seq, "%pM %4i.%03is   (%3i) %pM [%10s]:",
				   orig_node->orig, last_seen_secs,
				   last_seen_msecs, n_ifinfo->bat_iv.tq_avg,
				   neigh_node->addr,
				   neigh_node->if_incoming->net_dev->name);

			batadv_iv_ogm_orig_print_neigh(orig_node, if_outgoing,
						       seq);
			seq_puts(seq, "\n");
			batman_count++;

next:
			batadv_neigh_node_put(neigh_node);
			if (n_ifinfo)
				batadv_neigh_ifinfo_put(n_ifinfo);
		}
		rcu_read_unlock();
	}

	if (batman_count == 0)
		seq_puts(seq, "No batman nodes in range ...\n");
}

/**
 * batadv_iv_hardif_neigh_print - print a single hop neighbour node
 * @seq: neighbour table seq_file struct
 * @hardif_neigh: hardif neighbour information
 */
static void
batadv_iv_hardif_neigh_print(struct seq_file *seq,
			     struct batadv_hardif_neigh_node *hardif_neigh)
{
	int last_secs, last_msecs;

	last_secs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen) / 1000;
	last_msecs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen) % 1000;

	seq_printf(seq, "   %10s   %pM %4i.%03is\n",
		   hardif_neigh->if_incoming->net_dev->name,
		   hardif_neigh->addr, last_secs, last_msecs);
}

/**
 * batadv_iv_ogm_neigh_print - print the single hop neighbour list
 * @bat_priv: the bat priv with all the soft interface information
 * @seq: neighbour table seq_file struct
 */
static void batadv_iv_neigh_print(struct batadv_priv *bat_priv,
				  struct seq_file *seq)
{
	struct net_device *net_dev = (struct net_device *)seq->private;
	struct batadv_hardif_neigh_node *hardif_neigh;
	struct batadv_hard_iface *hard_iface;
	int batman_count = 0;

	seq_puts(seq, "           IF        Neighbor      last-seen\n");

	rcu_read_lock();
	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
		if (hard_iface->soft_iface != net_dev)
			continue;

		hlist_for_each_entry_rcu(hardif_neigh,
					 &hard_iface->neigh_list, list) {
			batadv_iv_hardif_neigh_print(seq, hardif_neigh);
			batman_count++;
		}
	}
	rcu_read_unlock();

	if (batman_count == 0)
		seq_puts(seq, "No batman nodes in range ...\n");
}

/**
 * batadv_iv_ogm_neigh_cmp - compare the metrics of two neighbors
 * @neigh1: the first neighbor object of the comparison
 * @if_outgoing1: outgoing interface for the first neighbor
 * @neigh2: the second neighbor object of the comparison
 * @if_outgoing2: outgoing interface for the second neighbor
 *
 * Return: a value less, equal to or greater than 0 if the metric via neigh1 is
 * lower, the same as or higher than the metric via neigh2
 */
static int batadv_iv_ogm_neigh_cmp(struct batadv_neigh_node *neigh1,
				   struct batadv_hard_iface *if_outgoing1,
				   struct batadv_neigh_node *neigh2,
				   struct batadv_hard_iface *if_outgoing2)
{
	struct batadv_neigh_ifinfo *neigh1_ifinfo, *neigh2_ifinfo;
	u8 tq1, tq2;
	int diff;

	neigh1_ifinfo = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
	neigh2_ifinfo = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);

	if (!neigh1_ifinfo || !neigh2_ifinfo) {
		diff = 0;
		goto out;
	}

	tq1 = neigh1_ifinfo->bat_iv.tq_avg;
	tq2 = neigh2_ifinfo->bat_iv.tq_avg;
	diff = tq1 - tq2;

out:
	if (neigh1_ifinfo)
		batadv_neigh_ifinfo_put(neigh1_ifinfo);
	if (neigh2_ifinfo)
		batadv_neigh_ifinfo_put(neigh2_ifinfo);

	return diff;
}

/**
 * batadv_iv_ogm_neigh_is_sob - check if neigh1 is similarly good or better
 *  than neigh2 from the metric prospective
 * @neigh1: the first neighbor object of the comparison
 * @if_outgoing1: outgoing interface for the first neighbor
 * @neigh2: the second neighbor object of the comparison
 * @if_outgoing2: outgoing interface for the second neighbor
 *
 * Return: true if the metric via neigh1 is equally good or better than
 * the metric via neigh2, false otherwise.
 */
static bool
batadv_iv_ogm_neigh_is_sob(struct batadv_neigh_node *neigh1,
			   struct batadv_hard_iface *if_outgoing1,
			   struct batadv_neigh_node *neigh2,
			   struct batadv_hard_iface *if_outgoing2)
{
	struct batadv_neigh_ifinfo *neigh1_ifinfo, *neigh2_ifinfo;
	u8 tq1, tq2;
	bool ret;

	neigh1_ifinfo = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
	neigh2_ifinfo = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);

	/* we can't say that the metric is better */
	if (!neigh1_ifinfo || !neigh2_ifinfo) {
		ret = false;
		goto out;
	}

	tq1 = neigh1_ifinfo->bat_iv.tq_avg;
	tq2 = neigh2_ifinfo->bat_iv.tq_avg;
	ret = (tq1 - tq2) > -BATADV_TQ_SIMILARITY_THRESHOLD;

out:
	if (neigh1_ifinfo)
		batadv_neigh_ifinfo_put(neigh1_ifinfo);
	if (neigh2_ifinfo)
		batadv_neigh_ifinfo_put(neigh2_ifinfo);

	return ret;
}

static void batadv_iv_iface_activate(struct batadv_hard_iface *hard_iface)
{
	/* begin scheduling originator messages on that interface */
	batadv_iv_ogm_schedule(hard_iface);
}

static struct batadv_algo_ops batadv_batman_iv __read_mostly = {
	.name = "BATMAN_IV",
	.bat_iface_activate = batadv_iv_iface_activate,
	.bat_iface_enable = batadv_iv_ogm_iface_enable,
	.bat_iface_disable = batadv_iv_ogm_iface_disable,
	.bat_iface_update_mac = batadv_iv_ogm_iface_update_mac,
	.bat_primary_iface_set = batadv_iv_ogm_primary_iface_set,
	.bat_neigh_cmp = batadv_iv_ogm_neigh_cmp,
	.bat_neigh_is_similar_or_better = batadv_iv_ogm_neigh_is_sob,
	.bat_neigh_print = batadv_iv_neigh_print,
	.bat_orig_print = batadv_iv_ogm_orig_print,
	.bat_orig_free = batadv_iv_ogm_orig_free,
	.bat_orig_add_if = batadv_iv_ogm_orig_add_if,
	.bat_orig_del_if = batadv_iv_ogm_orig_del_if,
};

int __init batadv_iv_init(void)
{
	int ret;

	/* batman originator packet */
	ret = batadv_recv_handler_register(BATADV_IV_OGM,
					   batadv_iv_ogm_receive);
	if (ret < 0)
		goto out;

	ret = batadv_algo_register(&batadv_batman_iv);
	if (ret < 0)
		goto handler_unregister;

	goto out;

handler_unregister:
	batadv_recv_handler_unregister(BATADV_IV_OGM);
out:
	return ret;
}