summaryrefslogtreecommitdiff
path: root/net/batman-adv/multicast.c
blob: 9af99c39b9fd90c88d2b8efc48da0142fb9ca3db (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
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2014-2020  B.A.T.M.A.N. contributors:
 *
 * Linus Lüssing
 */

#include "multicast.h"
#include "main.h"

#include <linux/atomic.h>
#include <linux/bitops.h>
#include <linux/bug.h>
#include <linux/byteorder/generic.h>
#include <linux/errno.h>
#include <linux/etherdevice.h>
#include <linux/gfp.h>
#include <linux/icmpv6.h>
#include <linux/if_bridge.h>
#include <linux/if_ether.h>
#include <linux/igmp.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/inetdevice.h>
#include <linux/ip.h>
#include <linux/ipv6.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/netlink.h>
#include <linux/printk.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 <net/addrconf.h>
#include <net/genetlink.h>
#include <net/if_inet6.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <net/netlink.h>
#include <net/sock.h>
#include <uapi/linux/batadv_packet.h>
#include <uapi/linux/batman_adv.h>

#include "bridge_loop_avoidance.h"
#include "hard-interface.h"
#include "hash.h"
#include "log.h"
#include "netlink.h"
#include "send.h"
#include "soft-interface.h"
#include "translation-table.h"
#include "tvlv.h"

static void batadv_mcast_mla_update(struct work_struct *work);

/**
 * batadv_mcast_start_timer() - schedule the multicast periodic worker
 * @bat_priv: the bat priv with all the soft interface information
 */
static void batadv_mcast_start_timer(struct batadv_priv *bat_priv)
{
	queue_delayed_work(batadv_event_workqueue, &bat_priv->mcast.work,
			   msecs_to_jiffies(BATADV_MCAST_WORK_PERIOD));
}

/**
 * batadv_mcast_get_bridge() - get the bridge on top of the softif if it exists
 * @soft_iface: netdev struct of the mesh interface
 *
 * If the given soft interface has a bridge on top then the refcount
 * of the according net device is increased.
 *
 * Return: NULL if no such bridge exists. Otherwise the net device of the
 * bridge.
 */
static struct net_device *batadv_mcast_get_bridge(struct net_device *soft_iface)
{
	struct net_device *upper = soft_iface;

	rcu_read_lock();
	do {
		upper = netdev_master_upper_dev_get_rcu(upper);
	} while (upper && !(upper->priv_flags & IFF_EBRIDGE));

	if (upper)
		dev_hold(upper);
	rcu_read_unlock();

	return upper;
}

/**
 * batadv_mcast_mla_rtr_flags_softif_get_ipv4() - get mcast router flags from
 *  node for IPv4
 * @dev: the interface to check
 *
 * Checks the presence of an IPv4 multicast router on this node.
 *
 * Caller needs to hold rcu read lock.
 *
 * Return: BATADV_NO_FLAGS if present, BATADV_MCAST_WANT_NO_RTR4 otherwise.
 */
static u8 batadv_mcast_mla_rtr_flags_softif_get_ipv4(struct net_device *dev)
{
	struct in_device *in_dev = __in_dev_get_rcu(dev);

	if (in_dev && IN_DEV_MFORWARD(in_dev))
		return BATADV_NO_FLAGS;
	else
		return BATADV_MCAST_WANT_NO_RTR4;
}

/**
 * batadv_mcast_mla_rtr_flags_softif_get_ipv6() - get mcast router flags from
 *  node for IPv6
 * @dev: the interface to check
 *
 * Checks the presence of an IPv6 multicast router on this node.
 *
 * Caller needs to hold rcu read lock.
 *
 * Return: BATADV_NO_FLAGS if present, BATADV_MCAST_WANT_NO_RTR6 otherwise.
 */
#if IS_ENABLED(CONFIG_IPV6_MROUTE)
static u8 batadv_mcast_mla_rtr_flags_softif_get_ipv6(struct net_device *dev)
{
	struct inet6_dev *in6_dev = __in6_dev_get(dev);

	if (in6_dev && in6_dev->cnf.mc_forwarding)
		return BATADV_NO_FLAGS;
	else
		return BATADV_MCAST_WANT_NO_RTR6;
}
#else
static inline u8
batadv_mcast_mla_rtr_flags_softif_get_ipv6(struct net_device *dev)
{
	return BATADV_MCAST_WANT_NO_RTR6;
}
#endif

/**
 * batadv_mcast_mla_rtr_flags_softif_get() - get mcast router flags from node
 * @bat_priv: the bat priv with all the soft interface information
 * @bridge: bridge interface on top of the soft_iface if present,
 *  otherwise pass NULL
 *
 * Checks the presence of IPv4 and IPv6 multicast routers on this
 * node.
 *
 * Return:
 *	BATADV_NO_FLAGS: Both an IPv4 and IPv6 multicast router is present
 *	BATADV_MCAST_WANT_NO_RTR4: No IPv4 multicast router is present
 *	BATADV_MCAST_WANT_NO_RTR6: No IPv6 multicast router is present
 *	The former two OR'd: no multicast router is present
 */
static u8 batadv_mcast_mla_rtr_flags_softif_get(struct batadv_priv *bat_priv,
						struct net_device *bridge)
{
	struct net_device *dev = bridge ? bridge : bat_priv->soft_iface;
	u8 flags = BATADV_NO_FLAGS;

	rcu_read_lock();

	flags |= batadv_mcast_mla_rtr_flags_softif_get_ipv4(dev);
	flags |= batadv_mcast_mla_rtr_flags_softif_get_ipv6(dev);

	rcu_read_unlock();

	return flags;
}

/**
 * batadv_mcast_mla_rtr_flags_bridge_get() - get mcast router flags from bridge
 * @bat_priv: the bat priv with all the soft interface information
 * @bridge: bridge interface on top of the soft_iface if present,
 *  otherwise pass NULL
 *
 * Checks the presence of IPv4 and IPv6 multicast routers behind a bridge.
 *
 * Return:
 *	BATADV_NO_FLAGS: Both an IPv4 and IPv6 multicast router is present
 *	BATADV_MCAST_WANT_NO_RTR4: No IPv4 multicast router is present
 *	BATADV_MCAST_WANT_NO_RTR6: No IPv6 multicast router is present
 *	The former two OR'd: no multicast router is present
 */
#if IS_ENABLED(CONFIG_IPV6)
static u8 batadv_mcast_mla_rtr_flags_bridge_get(struct batadv_priv *bat_priv,
						struct net_device *bridge)
{
	struct list_head bridge_mcast_list = LIST_HEAD_INIT(bridge_mcast_list);
	struct net_device *dev = bat_priv->soft_iface;
	struct br_ip_list *br_ip_entry, *tmp;
	u8 flags = BATADV_MCAST_WANT_NO_RTR6;
	int ret;

	if (!bridge)
		return BATADV_MCAST_WANT_NO_RTR4 | BATADV_MCAST_WANT_NO_RTR6;

	/* TODO: ask the bridge if a multicast router is present (the bridge
	 * is capable of performing proper RFC4286 multicast router
	 * discovery) instead of searching for a ff02::2 listener here
	 */
	ret = br_multicast_list_adjacent(dev, &bridge_mcast_list);
	if (ret < 0)
		return BATADV_NO_FLAGS;

	list_for_each_entry_safe(br_ip_entry, tmp, &bridge_mcast_list, list) {
		/* the bridge snooping does not maintain IPv4 link-local
		 * addresses - therefore we won't find any IPv4 multicast router
		 * address here, only IPv6 ones
		 */
		if (br_ip_entry->addr.proto == htons(ETH_P_IPV6) &&
		    ipv6_addr_is_ll_all_routers(&br_ip_entry->addr.dst.ip6))
			flags &= ~BATADV_MCAST_WANT_NO_RTR6;

		list_del(&br_ip_entry->list);
		kfree(br_ip_entry);
	}

	return flags;
}
#else
static inline u8
batadv_mcast_mla_rtr_flags_bridge_get(struct batadv_priv *bat_priv,
				      struct net_device *bridge)
{
	if (bridge)
		return BATADV_NO_FLAGS;
	else
		return BATADV_MCAST_WANT_NO_RTR4 | BATADV_MCAST_WANT_NO_RTR6;
}
#endif

/**
 * batadv_mcast_mla_rtr_flags_get() - get multicast router flags
 * @bat_priv: the bat priv with all the soft interface information
 * @bridge: bridge interface on top of the soft_iface if present,
 *  otherwise pass NULL
 *
 * Checks the presence of IPv4 and IPv6 multicast routers on this
 * node or behind its bridge.
 *
 * Return:
 *	BATADV_NO_FLAGS: Both an IPv4 and IPv6 multicast router is present
 *	BATADV_MCAST_WANT_NO_RTR4: No IPv4 multicast router is present
 *	BATADV_MCAST_WANT_NO_RTR6: No IPv6 multicast router is present
 *	The former two OR'd: no multicast router is present
 */
static u8 batadv_mcast_mla_rtr_flags_get(struct batadv_priv *bat_priv,
					 struct net_device *bridge)
{
	u8 flags = BATADV_MCAST_WANT_NO_RTR4 | BATADV_MCAST_WANT_NO_RTR6;

	flags &= batadv_mcast_mla_rtr_flags_softif_get(bat_priv, bridge);
	flags &= batadv_mcast_mla_rtr_flags_bridge_get(bat_priv, bridge);

	return flags;
}

/**
 * batadv_mcast_mla_flags_get() - get the new multicast flags
 * @bat_priv: the bat priv with all the soft interface information
 *
 * Return: A set of flags for the current/next TVLV, querier and
 * bridge state.
 */
static struct batadv_mcast_mla_flags
batadv_mcast_mla_flags_get(struct batadv_priv *bat_priv)
{
	struct net_device *dev = bat_priv->soft_iface;
	struct batadv_mcast_querier_state *qr4, *qr6;
	struct batadv_mcast_mla_flags mla_flags;
	struct net_device *bridge;

	bridge = batadv_mcast_get_bridge(dev);

	memset(&mla_flags, 0, sizeof(mla_flags));
	mla_flags.enabled = 1;
	mla_flags.tvlv_flags |= batadv_mcast_mla_rtr_flags_get(bat_priv,
							       bridge);

	if (!bridge)
		return mla_flags;

	dev_put(bridge);

	mla_flags.bridged = 1;
	qr4 = &mla_flags.querier_ipv4;
	qr6 = &mla_flags.querier_ipv6;

	if (!IS_ENABLED(CONFIG_BRIDGE_IGMP_SNOOPING))
		pr_warn_once("No bridge IGMP snooping compiled - multicast optimizations disabled\n");

	qr4->exists = br_multicast_has_querier_anywhere(dev, ETH_P_IP);
	qr4->shadowing = br_multicast_has_querier_adjacent(dev, ETH_P_IP);

	qr6->exists = br_multicast_has_querier_anywhere(dev, ETH_P_IPV6);
	qr6->shadowing = br_multicast_has_querier_adjacent(dev, ETH_P_IPV6);

	mla_flags.tvlv_flags |= BATADV_MCAST_WANT_ALL_UNSNOOPABLES;

	/* 1) If no querier exists at all, then multicast listeners on
	 *    our local TT clients behind the bridge will keep silent.
	 * 2) If the selected querier is on one of our local TT clients,
	 *    behind the bridge, then this querier might shadow multicast
	 *    listeners on our local TT clients, behind this bridge.
	 *
	 * In both cases, we will signalize other batman nodes that
	 * we need all multicast traffic of the according protocol.
	 */
	if (!qr4->exists || qr4->shadowing) {
		mla_flags.tvlv_flags |= BATADV_MCAST_WANT_ALL_IPV4;
		mla_flags.tvlv_flags &= ~BATADV_MCAST_WANT_NO_RTR4;
	}

	if (!qr6->exists || qr6->shadowing) {
		mla_flags.tvlv_flags |= BATADV_MCAST_WANT_ALL_IPV6;
		mla_flags.tvlv_flags &= ~BATADV_MCAST_WANT_NO_RTR6;
	}

	return mla_flags;
}

/**
 * batadv_mcast_mla_is_duplicate() - check whether an address is in a list
 * @mcast_addr: the multicast address to check
 * @mcast_list: the list with multicast addresses to search in
 *
 * Return: true if the given address is already in the given list.
 * Otherwise returns false.
 */
static bool batadv_mcast_mla_is_duplicate(u8 *mcast_addr,
					  struct hlist_head *mcast_list)
{
	struct batadv_hw_addr *mcast_entry;

	hlist_for_each_entry(mcast_entry, mcast_list, list)
		if (batadv_compare_eth(mcast_entry->addr, mcast_addr))
			return true;

	return false;
}

/**
 * batadv_mcast_mla_softif_get_ipv4() - get softif IPv4 multicast listeners
 * @dev: the device to collect multicast addresses from
 * @mcast_list: a list to put found addresses into
 * @flags: flags indicating the new multicast state
 *
 * Collects multicast addresses of IPv4 multicast listeners residing
 * on this kernel on the given soft interface, dev, in
 * the given mcast_list. In general, multicast listeners provided by
 * your multicast receiving applications run directly on this node.
 *
 * Return: -ENOMEM on memory allocation error or the number of
 * items added to the mcast_list otherwise.
 */
static int
batadv_mcast_mla_softif_get_ipv4(struct net_device *dev,
				 struct hlist_head *mcast_list,
				 struct batadv_mcast_mla_flags *flags)
{
	struct batadv_hw_addr *new;
	struct in_device *in_dev;
	u8 mcast_addr[ETH_ALEN];
	struct ip_mc_list *pmc;
	int ret = 0;

	if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_IPV4)
		return 0;

	rcu_read_lock();

	in_dev = __in_dev_get_rcu(dev);
	if (!in_dev) {
		rcu_read_unlock();
		return 0;
	}

	for (pmc = rcu_dereference(in_dev->mc_list); pmc;
	     pmc = rcu_dereference(pmc->next_rcu)) {
		if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
		    ipv4_is_local_multicast(pmc->multiaddr))
			continue;

		if (!(flags->tvlv_flags & BATADV_MCAST_WANT_NO_RTR4) &&
		    !ipv4_is_local_multicast(pmc->multiaddr))
			continue;

		ip_eth_mc_map(pmc->multiaddr, mcast_addr);

		if (batadv_mcast_mla_is_duplicate(mcast_addr, mcast_list))
			continue;

		new = kmalloc(sizeof(*new), GFP_ATOMIC);
		if (!new) {
			ret = -ENOMEM;
			break;
		}

		ether_addr_copy(new->addr, mcast_addr);
		hlist_add_head(&new->list, mcast_list);
		ret++;
	}
	rcu_read_unlock();

	return ret;
}

/**
 * batadv_mcast_mla_softif_get_ipv6() - get softif IPv6 multicast listeners
 * @dev: the device to collect multicast addresses from
 * @mcast_list: a list to put found addresses into
 * @flags: flags indicating the new multicast state
 *
 * Collects multicast addresses of IPv6 multicast listeners residing
 * on this kernel on the given soft interface, dev, in
 * the given mcast_list. In general, multicast listeners provided by
 * your multicast receiving applications run directly on this node.
 *
 * Return: -ENOMEM on memory allocation error or the number of
 * items added to the mcast_list otherwise.
 */
#if IS_ENABLED(CONFIG_IPV6)
static int
batadv_mcast_mla_softif_get_ipv6(struct net_device *dev,
				 struct hlist_head *mcast_list,
				 struct batadv_mcast_mla_flags *flags)
{
	struct batadv_hw_addr *new;
	struct inet6_dev *in6_dev;
	u8 mcast_addr[ETH_ALEN];
	struct ifmcaddr6 *pmc6;
	int ret = 0;

	if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_IPV6)
		return 0;

	rcu_read_lock();

	in6_dev = __in6_dev_get(dev);
	if (!in6_dev) {
		rcu_read_unlock();
		return 0;
	}

	read_lock_bh(&in6_dev->lock);
	for (pmc6 = in6_dev->mc_list; pmc6; pmc6 = pmc6->next) {
		if (IPV6_ADDR_MC_SCOPE(&pmc6->mca_addr) <
		    IPV6_ADDR_SCOPE_LINKLOCAL)
			continue;

		if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
		    ipv6_addr_is_ll_all_nodes(&pmc6->mca_addr))
			continue;

		if (!(flags->tvlv_flags & BATADV_MCAST_WANT_NO_RTR6) &&
		    IPV6_ADDR_MC_SCOPE(&pmc6->mca_addr) >
		    IPV6_ADDR_SCOPE_LINKLOCAL)
			continue;

		ipv6_eth_mc_map(&pmc6->mca_addr, mcast_addr);

		if (batadv_mcast_mla_is_duplicate(mcast_addr, mcast_list))
			continue;

		new = kmalloc(sizeof(*new), GFP_ATOMIC);
		if (!new) {
			ret = -ENOMEM;
			break;
		}

		ether_addr_copy(new->addr, mcast_addr);
		hlist_add_head(&new->list, mcast_list);
		ret++;
	}
	read_unlock_bh(&in6_dev->lock);
	rcu_read_unlock();

	return ret;
}
#else
static inline int
batadv_mcast_mla_softif_get_ipv6(struct net_device *dev,
				 struct hlist_head *mcast_list,
				 struct batadv_mcast_mla_flags *flags)
{
	return 0;
}
#endif

/**
 * batadv_mcast_mla_softif_get() - get softif multicast listeners
 * @dev: the device to collect multicast addresses from
 * @mcast_list: a list to put found addresses into
 * @flags: flags indicating the new multicast state
 *
 * Collects multicast addresses of multicast listeners residing
 * on this kernel on the given soft interface, dev, in
 * the given mcast_list. In general, multicast listeners provided by
 * your multicast receiving applications run directly on this node.
 *
 * If there is a bridge interface on top of dev, collect from that one
 * instead. Just like with IP addresses and routes, multicast listeners
 * will(/should) register to the bridge interface instead of an
 * enslaved bat0.
 *
 * Return: -ENOMEM on memory allocation error or the number of
 * items added to the mcast_list otherwise.
 */
static int
batadv_mcast_mla_softif_get(struct net_device *dev,
			    struct hlist_head *mcast_list,
			    struct batadv_mcast_mla_flags *flags)
{
	struct net_device *bridge = batadv_mcast_get_bridge(dev);
	int ret4, ret6 = 0;

	if (bridge)
		dev = bridge;

	ret4 = batadv_mcast_mla_softif_get_ipv4(dev, mcast_list, flags);
	if (ret4 < 0)
		goto out;

	ret6 = batadv_mcast_mla_softif_get_ipv6(dev, mcast_list, flags);
	if (ret6 < 0) {
		ret4 = 0;
		goto out;
	}

out:
	if (bridge)
		dev_put(bridge);

	return ret4 + ret6;
}

/**
 * batadv_mcast_mla_br_addr_cpy() - copy a bridge multicast address
 * @dst: destination to write to - a multicast MAC address
 * @src: source to read from - a multicast IP address
 *
 * Converts a given multicast IPv4/IPv6 address from a bridge
 * to its matching multicast MAC address and copies it into the given
 * destination buffer.
 *
 * Caller needs to make sure the destination buffer can hold
 * at least ETH_ALEN bytes.
 */
static void batadv_mcast_mla_br_addr_cpy(char *dst, const struct br_ip *src)
{
	if (src->proto == htons(ETH_P_IP))
		ip_eth_mc_map(src->dst.ip4, dst);
#if IS_ENABLED(CONFIG_IPV6)
	else if (src->proto == htons(ETH_P_IPV6))
		ipv6_eth_mc_map(&src->dst.ip6, dst);
#endif
	else
		eth_zero_addr(dst);
}

/**
 * batadv_mcast_mla_bridge_get() - get bridged-in multicast listeners
 * @dev: a bridge slave whose bridge to collect multicast addresses from
 * @mcast_list: a list to put found addresses into
 * @flags: flags indicating the new multicast state
 *
 * Collects multicast addresses of multicast listeners residing
 * on foreign, non-mesh devices which we gave access to our mesh via
 * a bridge on top of the given soft interface, dev, in the given
 * mcast_list.
 *
 * Return: -ENOMEM on memory allocation error or the number of
 * items added to the mcast_list otherwise.
 */
static int batadv_mcast_mla_bridge_get(struct net_device *dev,
				       struct hlist_head *mcast_list,
				       struct batadv_mcast_mla_flags *flags)
{
	struct list_head bridge_mcast_list = LIST_HEAD_INIT(bridge_mcast_list);
	struct br_ip_list *br_ip_entry, *tmp;
	u8 tvlv_flags = flags->tvlv_flags;
	struct batadv_hw_addr *new;
	u8 mcast_addr[ETH_ALEN];
	int ret;

	/* we don't need to detect these devices/listeners, the IGMP/MLD
	 * snooping code of the Linux bridge already does that for us
	 */
	ret = br_multicast_list_adjacent(dev, &bridge_mcast_list);
	if (ret < 0)
		goto out;

	list_for_each_entry(br_ip_entry, &bridge_mcast_list, list) {
		if (br_ip_entry->addr.proto == htons(ETH_P_IP)) {
			if (tvlv_flags & BATADV_MCAST_WANT_ALL_IPV4)
				continue;

			if (tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
			    ipv4_is_local_multicast(br_ip_entry->addr.dst.ip4))
				continue;

			if (!(tvlv_flags & BATADV_MCAST_WANT_NO_RTR4) &&
			    !ipv4_is_local_multicast(br_ip_entry->addr.dst.ip4))
				continue;
		}

#if IS_ENABLED(CONFIG_IPV6)
		if (br_ip_entry->addr.proto == htons(ETH_P_IPV6)) {
			if (tvlv_flags & BATADV_MCAST_WANT_ALL_IPV6)
				continue;

			if (tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
			    ipv6_addr_is_ll_all_nodes(&br_ip_entry->addr.dst.ip6))
				continue;

			if (!(tvlv_flags & BATADV_MCAST_WANT_NO_RTR6) &&
			    IPV6_ADDR_MC_SCOPE(&br_ip_entry->addr.dst.ip6) >
			    IPV6_ADDR_SCOPE_LINKLOCAL)
				continue;
		}
#endif

		batadv_mcast_mla_br_addr_cpy(mcast_addr, &br_ip_entry->addr);
		if (batadv_mcast_mla_is_duplicate(mcast_addr, mcast_list))
			continue;

		new = kmalloc(sizeof(*new), GFP_ATOMIC);
		if (!new) {
			ret = -ENOMEM;
			break;
		}

		ether_addr_copy(new->addr, mcast_addr);
		hlist_add_head(&new->list, mcast_list);
	}

out:
	list_for_each_entry_safe(br_ip_entry, tmp, &bridge_mcast_list, list) {
		list_del(&br_ip_entry->list);
		kfree(br_ip_entry);
	}

	return ret;
}

/**
 * batadv_mcast_mla_list_free() - free a list of multicast addresses
 * @mcast_list: the list to free
 *
 * Removes and frees all items in the given mcast_list.
 */
static void batadv_mcast_mla_list_free(struct hlist_head *mcast_list)
{
	struct batadv_hw_addr *mcast_entry;
	struct hlist_node *tmp;

	hlist_for_each_entry_safe(mcast_entry, tmp, mcast_list, list) {
		hlist_del(&mcast_entry->list);
		kfree(mcast_entry);
	}
}

/**
 * batadv_mcast_mla_tt_retract() - clean up multicast listener announcements
 * @bat_priv: the bat priv with all the soft interface information
 * @mcast_list: a list of addresses which should _not_ be removed
 *
 * Retracts the announcement of any multicast listener from the
 * translation table except the ones listed in the given mcast_list.
 *
 * If mcast_list is NULL then all are retracted.
 */
static void batadv_mcast_mla_tt_retract(struct batadv_priv *bat_priv,
					struct hlist_head *mcast_list)
{
	struct batadv_hw_addr *mcast_entry;
	struct hlist_node *tmp;

	hlist_for_each_entry_safe(mcast_entry, tmp, &bat_priv->mcast.mla_list,
				  list) {
		if (mcast_list &&
		    batadv_mcast_mla_is_duplicate(mcast_entry->addr,
						  mcast_list))
			continue;

		batadv_tt_local_remove(bat_priv, mcast_entry->addr,
				       BATADV_NO_FLAGS,
				       "mcast TT outdated", false);

		hlist_del(&mcast_entry->list);
		kfree(mcast_entry);
	}
}

/**
 * batadv_mcast_mla_tt_add() - add multicast listener announcements
 * @bat_priv: the bat priv with all the soft interface information
 * @mcast_list: a list of addresses which are going to get added
 *
 * Adds multicast listener announcements from the given mcast_list to the
 * translation table if they have not been added yet.
 */
static void batadv_mcast_mla_tt_add(struct batadv_priv *bat_priv,
				    struct hlist_head *mcast_list)
{
	struct batadv_hw_addr *mcast_entry;
	struct hlist_node *tmp;

	if (!mcast_list)
		return;

	hlist_for_each_entry_safe(mcast_entry, tmp, mcast_list, list) {
		if (batadv_mcast_mla_is_duplicate(mcast_entry->addr,
						  &bat_priv->mcast.mla_list))
			continue;

		if (!batadv_tt_local_add(bat_priv->soft_iface,
					 mcast_entry->addr, BATADV_NO_FLAGS,
					 BATADV_NULL_IFINDEX, BATADV_NO_MARK))
			continue;

		hlist_del(&mcast_entry->list);
		hlist_add_head(&mcast_entry->list, &bat_priv->mcast.mla_list);
	}
}

/**
 * batadv_mcast_querier_log() - debug output regarding the querier status on
 *  link
 * @bat_priv: the bat priv with all the soft interface information
 * @str_proto: a string for the querier protocol (e.g. "IGMP" or "MLD")
 * @old_state: the previous querier state on our link
 * @new_state: the new querier state on our link
 *
 * Outputs debug messages to the logging facility with log level 'mcast'
 * regarding changes to the querier status on the link which are relevant
 * to our multicast optimizations.
 *
 * Usually this is about whether a querier appeared or vanished in
 * our mesh or whether the querier is in the suboptimal position of being
 * behind our local bridge segment: Snooping switches will directly
 * forward listener reports to the querier, therefore batman-adv and
 * the bridge will potentially not see these listeners - the querier is
 * potentially shadowing listeners from us then.
 *
 * This is only interesting for nodes with a bridge on top of their
 * soft interface.
 */
static void
batadv_mcast_querier_log(struct batadv_priv *bat_priv, char *str_proto,
			 struct batadv_mcast_querier_state *old_state,
			 struct batadv_mcast_querier_state *new_state)
{
	if (!old_state->exists && new_state->exists)
		batadv_info(bat_priv->soft_iface, "%s Querier appeared\n",
			    str_proto);
	else if (old_state->exists && !new_state->exists)
		batadv_info(bat_priv->soft_iface,
			    "%s Querier disappeared - multicast optimizations disabled\n",
			    str_proto);
	else if (!bat_priv->mcast.mla_flags.bridged && !new_state->exists)
		batadv_info(bat_priv->soft_iface,
			    "No %s Querier present - multicast optimizations disabled\n",
			    str_proto);

	if (new_state->exists) {
		if ((!old_state->shadowing && new_state->shadowing) ||
		    (!old_state->exists && new_state->shadowing))
			batadv_dbg(BATADV_DBG_MCAST, bat_priv,
				   "%s Querier is behind our bridged segment: Might shadow listeners\n",
				   str_proto);
		else if (old_state->shadowing && !new_state->shadowing)
			batadv_dbg(BATADV_DBG_MCAST, bat_priv,
				   "%s Querier is not behind our bridged segment\n",
				   str_proto);
	}
}

/**
 * batadv_mcast_bridge_log() - debug output for topology changes in bridged
 *  setups
 * @bat_priv: the bat priv with all the soft interface information
 * @new_flags: flags indicating the new multicast state
 *
 * If no bridges are ever used on this node, then this function does nothing.
 *
 * Otherwise this function outputs debug information to the 'mcast' log level
 * which might be relevant to our multicast optimizations.
 *
 * More precisely, it outputs information when a bridge interface is added or
 * removed from a soft interface. And when a bridge is present, it further
 * outputs information about the querier state which is relevant for the
 * multicast flags this node is going to set.
 */
static void
batadv_mcast_bridge_log(struct batadv_priv *bat_priv,
			struct batadv_mcast_mla_flags *new_flags)
{
	struct batadv_mcast_mla_flags *old_flags = &bat_priv->mcast.mla_flags;

	if (!old_flags->bridged && new_flags->bridged)
		batadv_dbg(BATADV_DBG_MCAST, bat_priv,
			   "Bridge added: Setting Unsnoopables(U)-flag\n");
	else if (old_flags->bridged && !new_flags->bridged)
		batadv_dbg(BATADV_DBG_MCAST, bat_priv,
			   "Bridge removed: Unsetting Unsnoopables(U)-flag\n");

	if (new_flags->bridged) {
		batadv_mcast_querier_log(bat_priv, "IGMP",
					 &old_flags->querier_ipv4,
					 &new_flags->querier_ipv4);
		batadv_mcast_querier_log(bat_priv, "MLD",
					 &old_flags->querier_ipv6,
					 &new_flags->querier_ipv6);
	}
}

/**
 * batadv_mcast_flags_logs() - output debug information about mcast flag changes
 * @bat_priv: the bat priv with all the soft interface information
 * @flags: TVLV flags indicating the new multicast state
 *
 * Whenever the multicast TVLV flags this node announces change, this function
 * should be used to notify userspace about the change.
 */
static void batadv_mcast_flags_log(struct batadv_priv *bat_priv, u8 flags)
{
	bool old_enabled = bat_priv->mcast.mla_flags.enabled;
	u8 old_flags = bat_priv->mcast.mla_flags.tvlv_flags;
	char str_old_flags[] = "[.... . ]";

	sprintf(str_old_flags, "[%c%c%c%s%s]",
		(old_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) ? 'U' : '.',
		(old_flags & BATADV_MCAST_WANT_ALL_IPV4) ? '4' : '.',
		(old_flags & BATADV_MCAST_WANT_ALL_IPV6) ? '6' : '.',
		!(old_flags & BATADV_MCAST_WANT_NO_RTR4) ? "R4" : ". ",
		!(old_flags & BATADV_MCAST_WANT_NO_RTR6) ? "R6" : ". ");

	batadv_dbg(BATADV_DBG_MCAST, bat_priv,
		   "Changing multicast flags from '%s' to '[%c%c%c%s%s]'\n",
		   old_enabled ? str_old_flags : "<undefined>",
		   (flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) ? 'U' : '.',
		   (flags & BATADV_MCAST_WANT_ALL_IPV4) ? '4' : '.',
		   (flags & BATADV_MCAST_WANT_ALL_IPV6) ? '6' : '.',
		   !(flags & BATADV_MCAST_WANT_NO_RTR4) ? "R4" : ". ",
		   !(flags & BATADV_MCAST_WANT_NO_RTR6) ? "R6" : ". ");
}

/**
 * batadv_mcast_mla_flags_update() - update multicast flags
 * @bat_priv: the bat priv with all the soft interface information
 * @flags: flags indicating the new multicast state
 *
 * Updates the own multicast tvlv with our current multicast related settings,
 * capabilities and inabilities.
 */
static void
batadv_mcast_mla_flags_update(struct batadv_priv *bat_priv,
			      struct batadv_mcast_mla_flags *flags)
{
	struct batadv_tvlv_mcast_data mcast_data;

	if (!memcmp(flags, &bat_priv->mcast.mla_flags, sizeof(*flags)))
		return;

	batadv_mcast_bridge_log(bat_priv, flags);
	batadv_mcast_flags_log(bat_priv, flags->tvlv_flags);

	mcast_data.flags = flags->tvlv_flags;
	memset(mcast_data.reserved, 0, sizeof(mcast_data.reserved));

	batadv_tvlv_container_register(bat_priv, BATADV_TVLV_MCAST, 2,
				       &mcast_data, sizeof(mcast_data));

	bat_priv->mcast.mla_flags = *flags;
}

/**
 * __batadv_mcast_mla_update() - update the own MLAs
 * @bat_priv: the bat priv with all the soft interface information
 *
 * Updates the own multicast listener announcements in the translation
 * table as well as the own, announced multicast tvlv container.
 *
 * Note that non-conflicting reads and writes to bat_priv->mcast.mla_list
 * in batadv_mcast_mla_tt_retract() and batadv_mcast_mla_tt_add() are
 * ensured by the non-parallel execution of the worker this function
 * belongs to.
 */
static void __batadv_mcast_mla_update(struct batadv_priv *bat_priv)
{
	struct net_device *soft_iface = bat_priv->soft_iface;
	struct hlist_head mcast_list = HLIST_HEAD_INIT;
	struct batadv_mcast_mla_flags flags;
	int ret;

	flags = batadv_mcast_mla_flags_get(bat_priv);

	ret = batadv_mcast_mla_softif_get(soft_iface, &mcast_list, &flags);
	if (ret < 0)
		goto out;

	ret = batadv_mcast_mla_bridge_get(soft_iface, &mcast_list, &flags);
	if (ret < 0)
		goto out;

	spin_lock(&bat_priv->mcast.mla_lock);
	batadv_mcast_mla_tt_retract(bat_priv, &mcast_list);
	batadv_mcast_mla_tt_add(bat_priv, &mcast_list);
	batadv_mcast_mla_flags_update(bat_priv, &flags);
	spin_unlock(&bat_priv->mcast.mla_lock);

out:
	batadv_mcast_mla_list_free(&mcast_list);
}

/**
 * batadv_mcast_mla_update() - update the own MLAs
 * @work: kernel work struct
 *
 * Updates the own multicast listener announcements in the translation
 * table as well as the own, announced multicast tvlv container.
 *
 * In the end, reschedules the work timer.
 */
static void batadv_mcast_mla_update(struct work_struct *work)
{
	struct delayed_work *delayed_work;
	struct batadv_priv_mcast *priv_mcast;
	struct batadv_priv *bat_priv;

	delayed_work = to_delayed_work(work);
	priv_mcast = container_of(delayed_work, struct batadv_priv_mcast, work);
	bat_priv = container_of(priv_mcast, struct batadv_priv, mcast);

	__batadv_mcast_mla_update(bat_priv);
	batadv_mcast_start_timer(bat_priv);
}

/**
 * batadv_mcast_is_report_ipv4() - check for IGMP reports
 * @skb: the ethernet frame destined for the mesh
 *
 * This call might reallocate skb data.
 *
 * Checks whether the given frame is a valid IGMP report.
 *
 * Return: If so then true, otherwise false.
 */
static bool batadv_mcast_is_report_ipv4(struct sk_buff *skb)
{
	if (ip_mc_check_igmp(skb) < 0)
		return false;

	switch (igmp_hdr(skb)->type) {
	case IGMP_HOST_MEMBERSHIP_REPORT:
	case IGMPV2_HOST_MEMBERSHIP_REPORT:
	case IGMPV3_HOST_MEMBERSHIP_REPORT:
		return true;
	}

	return false;
}

/**
 * batadv_mcast_forw_mode_check_ipv4() - check for optimized forwarding
 *  potential
 * @bat_priv: the bat priv with all the soft interface information
 * @skb: the IPv4 packet to check
 * @is_unsnoopable: stores whether the destination is snoopable
 * @is_routable: stores whether the destination is routable
 *
 * Checks whether the given IPv4 packet has the potential to be forwarded with a
 * mode more optimal than classic flooding.
 *
 * Return: If so then 0. Otherwise -EINVAL or -ENOMEM in case of memory
 * allocation failure.
 */
static int batadv_mcast_forw_mode_check_ipv4(struct batadv_priv *bat_priv,
					     struct sk_buff *skb,
					     bool *is_unsnoopable,
					     int *is_routable)
{
	struct iphdr *iphdr;

	/* We might fail due to out-of-memory -> drop it */
	if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*iphdr)))
		return -ENOMEM;

	if (batadv_mcast_is_report_ipv4(skb))
		return -EINVAL;

	iphdr = ip_hdr(skb);

	/* link-local multicast listeners behind a bridge are
	 * not snoopable (see RFC4541, section 2.1.2.2)
	 */
	if (ipv4_is_local_multicast(iphdr->daddr))
		*is_unsnoopable = true;
	else
		*is_routable = ETH_P_IP;

	return 0;
}

/**
 * batadv_mcast_is_report_ipv6() - check for MLD reports
 * @skb: the ethernet frame destined for the mesh
 *
 * This call might reallocate skb data.
 *
 * Checks whether the given frame is a valid MLD report.
 *
 * Return: If so then true, otherwise false.
 */
static bool batadv_mcast_is_report_ipv6(struct sk_buff *skb)
{
	if (ipv6_mc_check_mld(skb) < 0)
		return false;

	switch (icmp6_hdr(skb)->icmp6_type) {
	case ICMPV6_MGM_REPORT:
	case ICMPV6_MLD2_REPORT:
		return true;
	}

	return false;
}

/**
 * batadv_mcast_forw_mode_check_ipv6() - check for optimized forwarding
 *  potential
 * @bat_priv: the bat priv with all the soft interface information
 * @skb: the IPv6 packet to check
 * @is_unsnoopable: stores whether the destination is snoopable
 * @is_routable: stores whether the destination is routable
 *
 * Checks whether the given IPv6 packet has the potential to be forwarded with a
 * mode more optimal than classic flooding.
 *
 * Return: If so then 0. Otherwise -EINVAL is or -ENOMEM if we are out of memory
 */
static int batadv_mcast_forw_mode_check_ipv6(struct batadv_priv *bat_priv,
					     struct sk_buff *skb,
					     bool *is_unsnoopable,
					     int *is_routable)
{
	struct ipv6hdr *ip6hdr;

	/* We might fail due to out-of-memory -> drop it */
	if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*ip6hdr)))
		return -ENOMEM;

	if (batadv_mcast_is_report_ipv6(skb))
		return -EINVAL;

	ip6hdr = ipv6_hdr(skb);

	if (IPV6_ADDR_MC_SCOPE(&ip6hdr->daddr) < IPV6_ADDR_SCOPE_LINKLOCAL)
		return -EINVAL;

	/* link-local-all-nodes multicast listeners behind a bridge are
	 * not snoopable (see RFC4541, section 3, paragraph 3)
	 */
	if (ipv6_addr_is_ll_all_nodes(&ip6hdr->daddr))
		*is_unsnoopable = true;
	else if (IPV6_ADDR_MC_SCOPE(&ip6hdr->daddr) > IPV6_ADDR_SCOPE_LINKLOCAL)
		*is_routable = ETH_P_IPV6;

	return 0;
}

/**
 * batadv_mcast_forw_mode_check() - check for optimized forwarding potential
 * @bat_priv: the bat priv with all the soft interface information
 * @skb: the multicast frame to check
 * @is_unsnoopable: stores whether the destination is snoopable
 * @is_routable: stores whether the destination is routable
 *
 * Checks whether the given multicast ethernet frame has the potential to be
 * forwarded with a mode more optimal than classic flooding.
 *
 * Return: If so then 0. Otherwise -EINVAL is or -ENOMEM if we are out of memory
 */
static int batadv_mcast_forw_mode_check(struct batadv_priv *bat_priv,
					struct sk_buff *skb,
					bool *is_unsnoopable,
					int *is_routable)
{
	struct ethhdr *ethhdr = eth_hdr(skb);

	if (!atomic_read(&bat_priv->multicast_mode))
		return -EINVAL;

	switch (ntohs(ethhdr->h_proto)) {
	case ETH_P_IP:
		return batadv_mcast_forw_mode_check_ipv4(bat_priv, skb,
							 is_unsnoopable,
							 is_routable);
	case ETH_P_IPV6:
		if (!IS_ENABLED(CONFIG_IPV6))
			return -EINVAL;

		return batadv_mcast_forw_mode_check_ipv6(bat_priv, skb,
							 is_unsnoopable,
							 is_routable);
	default:
		return -EINVAL;
	}
}

/**
 * batadv_mcast_forw_want_all_ip_count() - count nodes with unspecific mcast
 *  interest
 * @bat_priv: the bat priv with all the soft interface information
 * @ethhdr: ethernet header of a packet
 *
 * Return: the number of nodes which want all IPv4 multicast traffic if the
 * given ethhdr is from an IPv4 packet or the number of nodes which want all
 * IPv6 traffic if it matches an IPv6 packet.
 */
static int batadv_mcast_forw_want_all_ip_count(struct batadv_priv *bat_priv,
					       struct ethhdr *ethhdr)
{
	switch (ntohs(ethhdr->h_proto)) {
	case ETH_P_IP:
		return atomic_read(&bat_priv->mcast.num_want_all_ipv4);
	case ETH_P_IPV6:
		return atomic_read(&bat_priv->mcast.num_want_all_ipv6);
	default:
		/* we shouldn't be here... */
		return 0;
	}
}

/**
 * batadv_mcast_forw_rtr_count() - count nodes with a multicast router
 * @bat_priv: the bat priv with all the soft interface information
 * @protocol: the ethernet protocol type to count multicast routers for
 *
 * Return: the number of nodes which want all routable IPv4 multicast traffic
 * if the protocol is ETH_P_IP or the number of nodes which want all routable
 * IPv6 traffic if the protocol is ETH_P_IPV6. Otherwise returns 0.
 */

static int batadv_mcast_forw_rtr_count(struct batadv_priv *bat_priv,
				       int protocol)
{
	switch (protocol) {
	case ETH_P_IP:
		return atomic_read(&bat_priv->mcast.num_want_all_rtr4);
	case ETH_P_IPV6:
		return atomic_read(&bat_priv->mcast.num_want_all_rtr6);
	default:
		return 0;
	}
}

/**
 * batadv_mcast_forw_tt_node_get() - get a multicast tt node
 * @bat_priv: the bat priv with all the soft interface information
 * @ethhdr: the ether header containing the multicast destination
 *
 * Return: an orig_node matching the multicast address provided by ethhdr
 * via a translation table lookup. This increases the returned nodes refcount.
 */
static struct batadv_orig_node *
batadv_mcast_forw_tt_node_get(struct batadv_priv *bat_priv,
			      struct ethhdr *ethhdr)
{
	return batadv_transtable_search(bat_priv, NULL, ethhdr->h_dest,
					BATADV_NO_FLAGS);
}

/**
 * batadv_mcast_forw_ipv4_node_get() - get a node with an ipv4 flag
 * @bat_priv: the bat priv with all the soft interface information
 *
 * Return: an orig_node which has the BATADV_MCAST_WANT_ALL_IPV4 flag set and
 * increases its refcount.
 */
static struct batadv_orig_node *
batadv_mcast_forw_ipv4_node_get(struct batadv_priv *bat_priv)
{
	struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;

	rcu_read_lock();
	hlist_for_each_entry_rcu(tmp_orig_node,
				 &bat_priv->mcast.want_all_ipv4_list,
				 mcast_want_all_ipv4_node) {
		if (!kref_get_unless_zero(&tmp_orig_node->refcount))
			continue;

		orig_node = tmp_orig_node;
		break;
	}
	rcu_read_unlock();

	return orig_node;
}

/**
 * batadv_mcast_forw_ipv6_node_get() - get a node with an ipv6 flag
 * @bat_priv: the bat priv with all the soft interface information
 *
 * Return: an orig_node which has the BATADV_MCAST_WANT_ALL_IPV6 flag set
 * and increases its refcount.
 */
static struct batadv_orig_node *
batadv_mcast_forw_ipv6_node_get(struct batadv_priv *bat_priv)
{
	struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;

	rcu_read_lock();
	hlist_for_each_entry_rcu(tmp_orig_node,
				 &bat_priv->mcast.want_all_ipv6_list,
				 mcast_want_all_ipv6_node) {
		if (!kref_get_unless_zero(&tmp_orig_node->refcount))
			continue;

		orig_node = tmp_orig_node;
		break;
	}
	rcu_read_unlock();

	return orig_node;
}

/**
 * batadv_mcast_forw_ip_node_get() - get a node with an ipv4/ipv6 flag
 * @bat_priv: the bat priv with all the soft interface information
 * @ethhdr: an ethernet header to determine the protocol family from
 *
 * Return: an orig_node which has the BATADV_MCAST_WANT_ALL_IPV4 or
 * BATADV_MCAST_WANT_ALL_IPV6 flag, depending on the provided ethhdr, sets and
 * increases its refcount.
 */
static struct batadv_orig_node *
batadv_mcast_forw_ip_node_get(struct batadv_priv *bat_priv,
			      struct ethhdr *ethhdr)
{
	switch (ntohs(ethhdr->h_proto)) {
	case ETH_P_IP:
		return batadv_mcast_forw_ipv4_node_get(bat_priv);
	case ETH_P_IPV6:
		return batadv_mcast_forw_ipv6_node_get(bat_priv);
	default:
		/* we shouldn't be here... */
		return NULL;
	}
}

/**
 * batadv_mcast_forw_unsnoop_node_get() - get a node with an unsnoopable flag
 * @bat_priv: the bat priv with all the soft interface information
 *
 * Return: an orig_node which has the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag
 * set and increases its refcount.
 */
static struct batadv_orig_node *
batadv_mcast_forw_unsnoop_node_get(struct batadv_priv *bat_priv)
{
	struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;

	rcu_read_lock();
	hlist_for_each_entry_rcu(tmp_orig_node,
				 &bat_priv->mcast.want_all_unsnoopables_list,
				 mcast_want_all_unsnoopables_node) {
		if (!kref_get_unless_zero(&tmp_orig_node->refcount))
			continue;

		orig_node = tmp_orig_node;
		break;
	}
	rcu_read_unlock();

	return orig_node;
}

/**
 * batadv_mcast_forw_rtr4_node_get() - get a node with an ipv4 mcast router flag
 * @bat_priv: the bat priv with all the soft interface information
 *
 * Return: an orig_node which has the BATADV_MCAST_WANT_NO_RTR4 flag unset and
 * increases its refcount.
 */
static struct batadv_orig_node *
batadv_mcast_forw_rtr4_node_get(struct batadv_priv *bat_priv)
{
	struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;

	rcu_read_lock();
	hlist_for_each_entry_rcu(tmp_orig_node,
				 &bat_priv->mcast.want_all_rtr4_list,
				 mcast_want_all_rtr4_node) {
		if (!kref_get_unless_zero(&tmp_orig_node->refcount))
			continue;

		orig_node = tmp_orig_node;
		break;
	}
	rcu_read_unlock();

	return orig_node;
}

/**
 * batadv_mcast_forw_rtr6_node_get() - get a node with an ipv6 mcast router flag
 * @bat_priv: the bat priv with all the soft interface information
 *
 * Return: an orig_node which has the BATADV_MCAST_WANT_NO_RTR6 flag unset
 * and increases its refcount.
 */
static struct batadv_orig_node *
batadv_mcast_forw_rtr6_node_get(struct batadv_priv *bat_priv)
{
	struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;

	rcu_read_lock();
	hlist_for_each_entry_rcu(tmp_orig_node,
				 &bat_priv->mcast.want_all_rtr6_list,
				 mcast_want_all_rtr6_node) {
		if (!kref_get_unless_zero(&tmp_orig_node->refcount))
			continue;

		orig_node = tmp_orig_node;
		break;
	}
	rcu_read_unlock();

	return orig_node;
}

/**
 * batadv_mcast_forw_rtr_node_get() - get a node with an ipv4/ipv6 router flag
 * @bat_priv: the bat priv with all the soft interface information
 * @ethhdr: an ethernet header to determine the protocol family from
 *
 * Return: an orig_node which has no BATADV_MCAST_WANT_NO_RTR4 or
 * BATADV_MCAST_WANT_NO_RTR6 flag, depending on the provided ethhdr, set and
 * increases its refcount.
 */
static struct batadv_orig_node *
batadv_mcast_forw_rtr_node_get(struct batadv_priv *bat_priv,
			       struct ethhdr *ethhdr)
{
	switch (ntohs(ethhdr->h_proto)) {
	case ETH_P_IP:
		return batadv_mcast_forw_rtr4_node_get(bat_priv);
	case ETH_P_IPV6:
		return batadv_mcast_forw_rtr6_node_get(bat_priv);
	default:
		/* we shouldn't be here... */
		return NULL;
	}
}

/**
 * batadv_mcast_forw_mode() - check on how to forward a multicast packet
 * @bat_priv: the bat priv with all the soft interface information
 * @skb: The multicast packet to check
 * @orig: an originator to be set to forward the skb to
 *
 * Return: the forwarding mode as enum batadv_forw_mode and in case of
 * BATADV_FORW_SINGLE set the orig to the single originator the skb
 * should be forwarded to.
 */
enum batadv_forw_mode
batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb,
		       struct batadv_orig_node **orig)
{
	int ret, tt_count, ip_count, unsnoop_count, total_count;
	bool is_unsnoopable = false;
	unsigned int mcast_fanout;
	struct ethhdr *ethhdr;
	int is_routable = 0;
	int rtr_count = 0;

	ret = batadv_mcast_forw_mode_check(bat_priv, skb, &is_unsnoopable,
					   &is_routable);
	if (ret == -ENOMEM)
		return BATADV_FORW_NONE;
	else if (ret < 0)
		return BATADV_FORW_ALL;

	ethhdr = eth_hdr(skb);

	tt_count = batadv_tt_global_hash_count(bat_priv, ethhdr->h_dest,
					       BATADV_NO_FLAGS);
	ip_count = batadv_mcast_forw_want_all_ip_count(bat_priv, ethhdr);
	unsnoop_count = !is_unsnoopable ? 0 :
			atomic_read(&bat_priv->mcast.num_want_all_unsnoopables);
	rtr_count = batadv_mcast_forw_rtr_count(bat_priv, is_routable);

	total_count = tt_count + ip_count + unsnoop_count + rtr_count;

	switch (total_count) {
	case 1:
		if (tt_count)
			*orig = batadv_mcast_forw_tt_node_get(bat_priv, ethhdr);
		else if (ip_count)
			*orig = batadv_mcast_forw_ip_node_get(bat_priv, ethhdr);
		else if (unsnoop_count)
			*orig = batadv_mcast_forw_unsnoop_node_get(bat_priv);
		else if (rtr_count)
			*orig = batadv_mcast_forw_rtr_node_get(bat_priv,
							       ethhdr);

		if (*orig)
			return BATADV_FORW_SINGLE;

		fallthrough;
	case 0:
		return BATADV_FORW_NONE;
	default:
		mcast_fanout = atomic_read(&bat_priv->multicast_fanout);

		if (!unsnoop_count && total_count <= mcast_fanout)
			return BATADV_FORW_SOME;
	}

	return BATADV_FORW_ALL;
}

/**
 * batadv_mcast_forw_send_orig() - send a multicast packet to an originator
 * @bat_priv: the bat priv with all the soft interface information
 * @skb: the multicast packet to send
 * @vid: the vlan identifier
 * @orig_node: the originator to send the packet to
 *
 * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
 */
int batadv_mcast_forw_send_orig(struct batadv_priv *bat_priv,
				struct sk_buff *skb,
				unsigned short vid,
				struct batadv_orig_node *orig_node)
{
	/* Avoid sending multicast-in-unicast packets to other BLA
	 * gateways - they already got the frame from the LAN side
	 * we share with them.
	 * TODO: Refactor to take BLA into account earlier, to avoid
	 * reducing the mcast_fanout count.
	 */
	if (batadv_bla_is_backbone_gw_orig(bat_priv, orig_node->orig, vid)) {
		dev_kfree_skb(skb);
		return NET_XMIT_SUCCESS;
	}

	return batadv_send_skb_unicast(bat_priv, skb, BATADV_UNICAST, 0,
				       orig_node, vid);
}

/**
 * batadv_mcast_forw_tt() - forwards a packet to multicast listeners
 * @bat_priv: the bat priv with all the soft interface information
 * @skb: the multicast packet to transmit
 * @vid: the vlan identifier
 *
 * Sends copies of a frame with multicast destination to any multicast
 * listener registered in the translation table. A transmission is performed
 * via a batman-adv unicast packet for each such destination node.
 *
 * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
 * otherwise.
 */
static int
batadv_mcast_forw_tt(struct batadv_priv *bat_priv, struct sk_buff *skb,
		     unsigned short vid)
{
	int ret = NET_XMIT_SUCCESS;
	struct sk_buff *newskb;

	struct batadv_tt_orig_list_entry *orig_entry;

	struct batadv_tt_global_entry *tt_global;
	const u8 *addr = eth_hdr(skb)->h_dest;

	tt_global = batadv_tt_global_hash_find(bat_priv, addr, vid);
	if (!tt_global)
		goto out;

	rcu_read_lock();
	hlist_for_each_entry_rcu(orig_entry, &tt_global->orig_list, list) {
		newskb = skb_copy(skb, GFP_ATOMIC);
		if (!newskb) {
			ret = NET_XMIT_DROP;
			break;
		}

		batadv_mcast_forw_send_orig(bat_priv, newskb, vid,
					    orig_entry->orig_node);
	}
	rcu_read_unlock();

	batadv_tt_global_entry_put(tt_global);

out:
	return ret;
}

/**
 * batadv_mcast_forw_want_all_ipv4() - forward to nodes with want-all-ipv4
 * @bat_priv: the bat priv with all the soft interface information
 * @skb: the multicast packet to transmit
 * @vid: the vlan identifier
 *
 * Sends copies of a frame with multicast destination to any node with a
 * BATADV_MCAST_WANT_ALL_IPV4 flag set. A transmission is performed via a
 * batman-adv unicast packet for each such destination node.
 *
 * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
 * otherwise.
 */
static int
batadv_mcast_forw_want_all_ipv4(struct batadv_priv *bat_priv,
				struct sk_buff *skb, unsigned short vid)
{
	struct batadv_orig_node *orig_node;
	int ret = NET_XMIT_SUCCESS;
	struct sk_buff *newskb;

	rcu_read_lock();
	hlist_for_each_entry_rcu(orig_node,
				 &bat_priv->mcast.want_all_ipv4_list,
				 mcast_want_all_ipv4_node) {
		newskb = skb_copy(skb, GFP_ATOMIC);
		if (!newskb) {
			ret = NET_XMIT_DROP;
			break;
		}

		batadv_mcast_forw_send_orig(bat_priv, newskb, vid, orig_node);
	}
	rcu_read_unlock();
	return ret;
}

/**
 * batadv_mcast_forw_want_all_ipv6() - forward to nodes with want-all-ipv6
 * @bat_priv: the bat priv with all the soft interface information
 * @skb: The multicast packet to transmit
 * @vid: the vlan identifier
 *
 * Sends copies of a frame with multicast destination to any node with a
 * BATADV_MCAST_WANT_ALL_IPV6 flag set. A transmission is performed via a
 * batman-adv unicast packet for each such destination node.
 *
 * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
 * otherwise.
 */
static int
batadv_mcast_forw_want_all_ipv6(struct batadv_priv *bat_priv,
				struct sk_buff *skb, unsigned short vid)
{
	struct batadv_orig_node *orig_node;
	int ret = NET_XMIT_SUCCESS;
	struct sk_buff *newskb;

	rcu_read_lock();
	hlist_for_each_entry_rcu(orig_node,
				 &bat_priv->mcast.want_all_ipv6_list,
				 mcast_want_all_ipv6_node) {
		newskb = skb_copy(skb, GFP_ATOMIC);
		if (!newskb) {
			ret = NET_XMIT_DROP;
			break;
		}

		batadv_mcast_forw_send_orig(bat_priv, newskb, vid, orig_node);
	}
	rcu_read_unlock();
	return ret;
}

/**
 * batadv_mcast_forw_want_all() - forward packet to nodes in a want-all list
 * @bat_priv: the bat priv with all the soft interface information
 * @skb: the multicast packet to transmit
 * @vid: the vlan identifier
 *
 * Sends copies of a frame with multicast destination to any node with a
 * BATADV_MCAST_WANT_ALL_IPV4 or BATADV_MCAST_WANT_ALL_IPV6 flag set. A
 * transmission is performed via a batman-adv unicast packet for each such
 * destination node.
 *
 * Return: NET_XMIT_DROP on memory allocation failure or if the protocol family
 * is neither IPv4 nor IPv6. NET_XMIT_SUCCESS otherwise.
 */
static int
batadv_mcast_forw_want_all(struct batadv_priv *bat_priv,
			   struct sk_buff *skb, unsigned short vid)
{
	switch (ntohs(eth_hdr(skb)->h_proto)) {
	case ETH_P_IP:
		return batadv_mcast_forw_want_all_ipv4(bat_priv, skb, vid);
	case ETH_P_IPV6:
		return batadv_mcast_forw_want_all_ipv6(bat_priv, skb, vid);
	default:
		/* we shouldn't be here... */
		return NET_XMIT_DROP;
	}
}

/**
 * batadv_mcast_forw_want_all_rtr4() - forward to nodes with want-all-rtr4
 * @bat_priv: the bat priv with all the soft interface information
 * @skb: the multicast packet to transmit
 * @vid: the vlan identifier
 *
 * Sends copies of a frame with multicast destination to any node with a
 * BATADV_MCAST_WANT_NO_RTR4 flag unset. A transmission is performed via a
 * batman-adv unicast packet for each such destination node.
 *
 * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
 * otherwise.
 */
static int
batadv_mcast_forw_want_all_rtr4(struct batadv_priv *bat_priv,
				struct sk_buff *skb, unsigned short vid)
{
	struct batadv_orig_node *orig_node;
	int ret = NET_XMIT_SUCCESS;
	struct sk_buff *newskb;

	rcu_read_lock();
	hlist_for_each_entry_rcu(orig_node,
				 &bat_priv->mcast.want_all_rtr4_list,
				 mcast_want_all_rtr4_node) {
		newskb = skb_copy(skb, GFP_ATOMIC);
		if (!newskb) {
			ret = NET_XMIT_DROP;
			break;
		}

		batadv_mcast_forw_send_orig(bat_priv, newskb, vid, orig_node);
	}
	rcu_read_unlock();
	return ret;
}

/**
 * batadv_mcast_forw_want_all_rtr6() - forward to nodes with want-all-rtr6
 * @bat_priv: the bat priv with all the soft interface information
 * @skb: The multicast packet to transmit
 * @vid: the vlan identifier
 *
 * Sends copies of a frame with multicast destination to any node with a
 * BATADV_MCAST_WANT_NO_RTR6 flag unset. A transmission is performed via a
 * batman-adv unicast packet for each such destination node.
 *
 * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
 * otherwise.
 */
static int
batadv_mcast_forw_want_all_rtr6(struct batadv_priv *bat_priv,
				struct sk_buff *skb, unsigned short vid)
{
	struct batadv_orig_node *orig_node;
	int ret = NET_XMIT_SUCCESS;
	struct sk_buff *newskb;

	rcu_read_lock();
	hlist_for_each_entry_rcu(orig_node,
				 &bat_priv->mcast.want_all_rtr6_list,
				 mcast_want_all_rtr6_node) {
		newskb = skb_copy(skb, GFP_ATOMIC);
		if (!newskb) {
			ret = NET_XMIT_DROP;
			break;
		}

		batadv_mcast_forw_send_orig(bat_priv, newskb, vid, orig_node);
	}
	rcu_read_unlock();
	return ret;
}

/**
 * batadv_mcast_forw_want_rtr() - forward packet to nodes in a want-all-rtr list
 * @bat_priv: the bat priv with all the soft interface information
 * @skb: the multicast packet to transmit
 * @vid: the vlan identifier
 *
 * Sends copies of a frame with multicast destination to any node with a
 * BATADV_MCAST_WANT_NO_RTR4 or BATADV_MCAST_WANT_NO_RTR6 flag unset. A
 * transmission is performed via a batman-adv unicast packet for each such
 * destination node.
 *
 * Return: NET_XMIT_DROP on memory allocation failure or if the protocol family
 * is neither IPv4 nor IPv6. NET_XMIT_SUCCESS otherwise.
 */
static int
batadv_mcast_forw_want_rtr(struct batadv_priv *bat_priv,
			   struct sk_buff *skb, unsigned short vid)
{
	switch (ntohs(eth_hdr(skb)->h_proto)) {
	case ETH_P_IP:
		return batadv_mcast_forw_want_all_rtr4(bat_priv, skb, vid);
	case ETH_P_IPV6:
		return batadv_mcast_forw_want_all_rtr6(bat_priv, skb, vid);
	default:
		/* we shouldn't be here... */
		return NET_XMIT_DROP;
	}
}

/**
 * batadv_mcast_forw_send() - send packet to any detected multicast recipient
 * @bat_priv: the bat priv with all the soft interface information
 * @skb: the multicast packet to transmit
 * @vid: the vlan identifier
 *
 * Sends copies of a frame with multicast destination to any node that signaled
 * interest in it, that is either via the translation table or the according
 * want-all flags. A transmission is performed via a batman-adv unicast packet
 * for each such destination node.
 *
 * The given skb is consumed/freed.
 *
 * Return: NET_XMIT_DROP on memory allocation failure or if the protocol family
 * is neither IPv4 nor IPv6. NET_XMIT_SUCCESS otherwise.
 */
int batadv_mcast_forw_send(struct batadv_priv *bat_priv, struct sk_buff *skb,
			   unsigned short vid)
{
	int ret;

	ret = batadv_mcast_forw_tt(bat_priv, skb, vid);
	if (ret != NET_XMIT_SUCCESS) {
		kfree_skb(skb);
		return ret;
	}

	ret = batadv_mcast_forw_want_all(bat_priv, skb, vid);
	if (ret != NET_XMIT_SUCCESS) {
		kfree_skb(skb);
		return ret;
	}

	ret = batadv_mcast_forw_want_rtr(bat_priv, skb, vid);
	if (ret != NET_XMIT_SUCCESS) {
		kfree_skb(skb);
		return ret;
	}

	consume_skb(skb);
	return ret;
}

/**
 * batadv_mcast_want_unsnoop_update() - update unsnoop counter and list
 * @bat_priv: the bat priv with all the soft interface information
 * @orig: the orig_node which multicast state might have changed of
 * @mcast_flags: flags indicating the new multicast state
 *
 * If the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag of this originator,
 * orig, has toggled then this method updates the counter and the list
 * accordingly.
 *
 * Caller needs to hold orig->mcast_handler_lock.
 */
static void batadv_mcast_want_unsnoop_update(struct batadv_priv *bat_priv,
					     struct batadv_orig_node *orig,
					     u8 mcast_flags)
{
	struct hlist_node *node = &orig->mcast_want_all_unsnoopables_node;
	struct hlist_head *head = &bat_priv->mcast.want_all_unsnoopables_list;

	lockdep_assert_held(&orig->mcast_handler_lock);

	/* switched from flag unset to set */
	if (mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
	    !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES)) {
		atomic_inc(&bat_priv->mcast.num_want_all_unsnoopables);

		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
		/* flag checks above + mcast_handler_lock prevents this */
		WARN_ON(!hlist_unhashed(node));

		hlist_add_head_rcu(node, head);
		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
	/* switched from flag set to unset */
	} else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) &&
		   orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) {
		atomic_dec(&bat_priv->mcast.num_want_all_unsnoopables);

		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
		/* flag checks above + mcast_handler_lock prevents this */
		WARN_ON(hlist_unhashed(node));

		hlist_del_init_rcu(node);
		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
	}
}

/**
 * batadv_mcast_want_ipv4_update() - update want-all-ipv4 counter and list
 * @bat_priv: the bat priv with all the soft interface information
 * @orig: the orig_node which multicast state might have changed of
 * @mcast_flags: flags indicating the new multicast state
 *
 * If the BATADV_MCAST_WANT_ALL_IPV4 flag of this originator, orig, has
 * toggled then this method updates the counter and the list accordingly.
 *
 * Caller needs to hold orig->mcast_handler_lock.
 */
static void batadv_mcast_want_ipv4_update(struct batadv_priv *bat_priv,
					  struct batadv_orig_node *orig,
					  u8 mcast_flags)
{
	struct hlist_node *node = &orig->mcast_want_all_ipv4_node;
	struct hlist_head *head = &bat_priv->mcast.want_all_ipv4_list;

	lockdep_assert_held(&orig->mcast_handler_lock);

	/* switched from flag unset to set */
	if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV4 &&
	    !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV4)) {
		atomic_inc(&bat_priv->mcast.num_want_all_ipv4);

		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
		/* flag checks above + mcast_handler_lock prevents this */
		WARN_ON(!hlist_unhashed(node));

		hlist_add_head_rcu(node, head);
		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
	/* switched from flag set to unset */
	} else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_IPV4) &&
		   orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV4) {
		atomic_dec(&bat_priv->mcast.num_want_all_ipv4);

		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
		/* flag checks above + mcast_handler_lock prevents this */
		WARN_ON(hlist_unhashed(node));

		hlist_del_init_rcu(node);
		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
	}
}

/**
 * batadv_mcast_want_ipv6_update() - update want-all-ipv6 counter and list
 * @bat_priv: the bat priv with all the soft interface information
 * @orig: the orig_node which multicast state might have changed of
 * @mcast_flags: flags indicating the new multicast state
 *
 * If the BATADV_MCAST_WANT_ALL_IPV6 flag of this originator, orig, has
 * toggled then this method updates the counter and the list accordingly.
 *
 * Caller needs to hold orig->mcast_handler_lock.
 */
static void batadv_mcast_want_ipv6_update(struct batadv_priv *bat_priv,
					  struct batadv_orig_node *orig,
					  u8 mcast_flags)
{
	struct hlist_node *node = &orig->mcast_want_all_ipv6_node;
	struct hlist_head *head = &bat_priv->mcast.want_all_ipv6_list;

	lockdep_assert_held(&orig->mcast_handler_lock);

	/* switched from flag unset to set */
	if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV6 &&
	    !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV6)) {
		atomic_inc(&bat_priv->mcast.num_want_all_ipv6);

		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
		/* flag checks above + mcast_handler_lock prevents this */
		WARN_ON(!hlist_unhashed(node));

		hlist_add_head_rcu(node, head);
		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
	/* switched from flag set to unset */
	} else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_IPV6) &&
		   orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV6) {
		atomic_dec(&bat_priv->mcast.num_want_all_ipv6);

		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
		/* flag checks above + mcast_handler_lock prevents this */
		WARN_ON(hlist_unhashed(node));

		hlist_del_init_rcu(node);
		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
	}
}

/**
 * batadv_mcast_want_rtr4_update() - update want-all-rtr4 counter and list
 * @bat_priv: the bat priv with all the soft interface information
 * @orig: the orig_node which multicast state might have changed of
 * @mcast_flags: flags indicating the new multicast state
 *
 * If the BATADV_MCAST_WANT_NO_RTR4 flag of this originator, orig, has
 * toggled then this method updates the counter and the list accordingly.
 *
 * Caller needs to hold orig->mcast_handler_lock.
 */
static void batadv_mcast_want_rtr4_update(struct batadv_priv *bat_priv,
					  struct batadv_orig_node *orig,
					  u8 mcast_flags)
{
	struct hlist_node *node = &orig->mcast_want_all_rtr4_node;
	struct hlist_head *head = &bat_priv->mcast.want_all_rtr4_list;

	lockdep_assert_held(&orig->mcast_handler_lock);

	/* switched from flag set to unset */
	if (!(mcast_flags & BATADV_MCAST_WANT_NO_RTR4) &&
	    orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR4) {
		atomic_inc(&bat_priv->mcast.num_want_all_rtr4);

		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
		/* flag checks above + mcast_handler_lock prevents this */
		WARN_ON(!hlist_unhashed(node));

		hlist_add_head_rcu(node, head);
		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
	/* switched from flag unset to set */
	} else if (mcast_flags & BATADV_MCAST_WANT_NO_RTR4 &&
		   !(orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR4)) {
		atomic_dec(&bat_priv->mcast.num_want_all_rtr4);

		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
		/* flag checks above + mcast_handler_lock prevents this */
		WARN_ON(hlist_unhashed(node));

		hlist_del_init_rcu(node);
		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
	}
}

/**
 * batadv_mcast_want_rtr6_update() - update want-all-rtr6 counter and list
 * @bat_priv: the bat priv with all the soft interface information
 * @orig: the orig_node which multicast state might have changed of
 * @mcast_flags: flags indicating the new multicast state
 *
 * If the BATADV_MCAST_WANT_NO_RTR6 flag of this originator, orig, has
 * toggled then this method updates the counter and the list accordingly.
 *
 * Caller needs to hold orig->mcast_handler_lock.
 */
static void batadv_mcast_want_rtr6_update(struct batadv_priv *bat_priv,
					  struct batadv_orig_node *orig,
					  u8 mcast_flags)
{
	struct hlist_node *node = &orig->mcast_want_all_rtr6_node;
	struct hlist_head *head = &bat_priv->mcast.want_all_rtr6_list;

	lockdep_assert_held(&orig->mcast_handler_lock);

	/* switched from flag set to unset */
	if (!(mcast_flags & BATADV_MCAST_WANT_NO_RTR6) &&
	    orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR6) {
		atomic_inc(&bat_priv->mcast.num_want_all_rtr6);

		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
		/* flag checks above + mcast_handler_lock prevents this */
		WARN_ON(!hlist_unhashed(node));

		hlist_add_head_rcu(node, head);
		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
	/* switched from flag unset to set */
	} else if (mcast_flags & BATADV_MCAST_WANT_NO_RTR6 &&
		   !(orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR6)) {
		atomic_dec(&bat_priv->mcast.num_want_all_rtr6);

		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
		/* flag checks above + mcast_handler_lock prevents this */
		WARN_ON(hlist_unhashed(node));

		hlist_del_init_rcu(node);
		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
	}
}

/**
 * batadv_mcast_tvlv_flags_get() - get multicast flags from an OGM TVLV
 * @enabled: whether the originator has multicast TVLV support enabled
 * @tvlv_value: tvlv buffer containing the multicast flags
 * @tvlv_value_len: tvlv buffer length
 *
 * Return: multicast flags for the given tvlv buffer
 */
static u8
batadv_mcast_tvlv_flags_get(bool enabled, void *tvlv_value, u16 tvlv_value_len)
{
	u8 mcast_flags = BATADV_NO_FLAGS;

	if (enabled && tvlv_value && tvlv_value_len >= sizeof(mcast_flags))
		mcast_flags = *(u8 *)tvlv_value;

	if (!enabled) {
		mcast_flags |= BATADV_MCAST_WANT_ALL_IPV4;
		mcast_flags |= BATADV_MCAST_WANT_ALL_IPV6;
	}

	/* remove redundant flags to avoid sending duplicate packets later */
	if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV4)
		mcast_flags |= BATADV_MCAST_WANT_NO_RTR4;

	if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV6)
		mcast_flags |= BATADV_MCAST_WANT_NO_RTR6;

	return mcast_flags;
}

/**
 * batadv_mcast_tvlv_ogm_handler() - process incoming multicast tvlv container
 * @bat_priv: the bat priv with all the soft interface information
 * @orig: the orig_node of the ogm
 * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
 * @tvlv_value: tvlv buffer containing the multicast data
 * @tvlv_value_len: tvlv buffer length
 */
static void batadv_mcast_tvlv_ogm_handler(struct batadv_priv *bat_priv,
					  struct batadv_orig_node *orig,
					  u8 flags,
					  void *tvlv_value,
					  u16 tvlv_value_len)
{
	bool orig_mcast_enabled = !(flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
	u8 mcast_flags;

	mcast_flags = batadv_mcast_tvlv_flags_get(orig_mcast_enabled,
						  tvlv_value, tvlv_value_len);

	spin_lock_bh(&orig->mcast_handler_lock);

	if (orig_mcast_enabled &&
	    !test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities)) {
		set_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities);
	} else if (!orig_mcast_enabled &&
		   test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities)) {
		clear_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities);
	}

	set_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capa_initialized);

	batadv_mcast_want_unsnoop_update(bat_priv, orig, mcast_flags);
	batadv_mcast_want_ipv4_update(bat_priv, orig, mcast_flags);
	batadv_mcast_want_ipv6_update(bat_priv, orig, mcast_flags);
	batadv_mcast_want_rtr4_update(bat_priv, orig, mcast_flags);
	batadv_mcast_want_rtr6_update(bat_priv, orig, mcast_flags);

	orig->mcast_flags = mcast_flags;
	spin_unlock_bh(&orig->mcast_handler_lock);
}

/**
 * batadv_mcast_init() - initialize the multicast optimizations structures
 * @bat_priv: the bat priv with all the soft interface information
 */
void batadv_mcast_init(struct batadv_priv *bat_priv)
{
	batadv_tvlv_handler_register(bat_priv, batadv_mcast_tvlv_ogm_handler,
				     NULL, BATADV_TVLV_MCAST, 2,
				     BATADV_TVLV_HANDLER_OGM_CIFNOTFND);

	INIT_DELAYED_WORK(&bat_priv->mcast.work, batadv_mcast_mla_update);
	batadv_mcast_start_timer(bat_priv);
}

#ifdef CONFIG_BATMAN_ADV_DEBUGFS
/**
 * batadv_mcast_flags_print_header() - print own mcast flags to debugfs table
 * @bat_priv: the bat priv with all the soft interface information
 * @seq: debugfs table seq_file struct
 *
 * Prints our own multicast flags including a more specific reason why
 * they are set, that is prints the bridge and querier state too, to
 * the debugfs table specified via @seq.
 */
static void batadv_mcast_flags_print_header(struct batadv_priv *bat_priv,
					    struct seq_file *seq)
{
	struct batadv_mcast_mla_flags *mla_flags = &bat_priv->mcast.mla_flags;
	char querier4, querier6, shadowing4, shadowing6;
	bool bridged = mla_flags->bridged;
	u8 flags = mla_flags->tvlv_flags;

	if (bridged) {
		querier4 = mla_flags->querier_ipv4.exists ? '.' : '4';
		querier6 = mla_flags->querier_ipv6.exists ? '.' : '6';
		shadowing4 = mla_flags->querier_ipv4.shadowing ? '4' : '.';
		shadowing6 = mla_flags->querier_ipv6.shadowing ? '6' : '.';
	} else {
		querier4 = '?';
		querier6 = '?';
		shadowing4 = '?';
		shadowing6 = '?';
	}

	seq_printf(seq, "Multicast flags (own flags: [%c%c%c%s%s])\n",
		   (flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) ? 'U' : '.',
		   (flags & BATADV_MCAST_WANT_ALL_IPV4) ? '4' : '.',
		   (flags & BATADV_MCAST_WANT_ALL_IPV6) ? '6' : '.',
		   !(flags & BATADV_MCAST_WANT_NO_RTR4) ? "R4" : ". ",
		   !(flags & BATADV_MCAST_WANT_NO_RTR6) ? "R6" : ". ");
	seq_printf(seq, "* Bridged [U]\t\t\t\t%c\n", bridged ? 'U' : '.');
	seq_printf(seq, "* No IGMP/MLD Querier [4/6]:\t\t%c/%c\n",
		   querier4, querier6);
	seq_printf(seq, "* Shadowing IGMP/MLD Querier [4/6]:\t%c/%c\n",
		   shadowing4, shadowing6);
	seq_puts(seq, "-------------------------------------------\n");
	seq_printf(seq, "       %-10s %s\n", "Originator", "Flags");
}

/**
 * batadv_mcast_flags_seq_print_text() - print the mcast flags of other nodes
 * @seq: seq file to print on
 * @offset: not used
 *
 * This prints a table of (primary) originators and their according
 * multicast flags, including (in the header) our own.
 *
 * Return: always 0
 */
int batadv_mcast_flags_seq_print_text(struct seq_file *seq, void *offset)
{
	struct net_device *net_dev = (struct net_device *)seq->private;
	struct batadv_priv *bat_priv = netdev_priv(net_dev);
	struct batadv_hard_iface *primary_if;
	struct batadv_hashtable *hash = bat_priv->orig_hash;
	struct batadv_orig_node *orig_node;
	struct hlist_head *head;
	u8 flags;
	u32 i;

	primary_if = batadv_seq_print_text_primary_if_get(seq);
	if (!primary_if)
		return 0;

	batadv_mcast_flags_print_header(bat_priv, seq);

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

		rcu_read_lock();
		hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
			if (!test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
				      &orig_node->capa_initialized))
				continue;

			if (!test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
				      &orig_node->capabilities)) {
				seq_printf(seq, "%pM -\n", orig_node->orig);
				continue;
			}

			flags = orig_node->mcast_flags;

			seq_printf(seq, "%pM [%c%c%c%s%s]\n", orig_node->orig,
				   (flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES)
				   ? 'U' : '.',
				   (flags & BATADV_MCAST_WANT_ALL_IPV4)
				   ? '4' : '.',
				   (flags & BATADV_MCAST_WANT_ALL_IPV6)
				   ? '6' : '.',
				   !(flags & BATADV_MCAST_WANT_NO_RTR4)
				   ? "R4" : ". ",
				   !(flags & BATADV_MCAST_WANT_NO_RTR6)
				   ? "R6" : ". ");
		}
		rcu_read_unlock();
	}

	batadv_hardif_put(primary_if);

	return 0;
}
#endif

/**
 * batadv_mcast_mesh_info_put() - put multicast info into a netlink message
 * @msg: buffer for the message
 * @bat_priv: the bat priv with all the soft interface information
 *
 * Return: 0 or error code.
 */
int batadv_mcast_mesh_info_put(struct sk_buff *msg,
			       struct batadv_priv *bat_priv)
{
	u32 flags = bat_priv->mcast.mla_flags.tvlv_flags;
	u32 flags_priv = BATADV_NO_FLAGS;

	if (bat_priv->mcast.mla_flags.bridged) {
		flags_priv |= BATADV_MCAST_FLAGS_BRIDGED;

		if (bat_priv->mcast.mla_flags.querier_ipv4.exists)
			flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV4_EXISTS;
		if (bat_priv->mcast.mla_flags.querier_ipv6.exists)
			flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV6_EXISTS;
		if (bat_priv->mcast.mla_flags.querier_ipv4.shadowing)
			flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV4_SHADOWING;
		if (bat_priv->mcast.mla_flags.querier_ipv6.shadowing)
			flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV6_SHADOWING;
	}

	if (nla_put_u32(msg, BATADV_ATTR_MCAST_FLAGS, flags) ||
	    nla_put_u32(msg, BATADV_ATTR_MCAST_FLAGS_PRIV, flags_priv))
		return -EMSGSIZE;

	return 0;
}

/**
 * batadv_mcast_flags_dump_entry() - dump one entry of the multicast flags table
 *  to a netlink socket
 * @msg: buffer for the message
 * @portid: netlink port
 * @cb: Control block containing additional options
 * @orig_node: originator to dump the multicast flags of
 *
 * Return: 0 or error code.
 */
static int
batadv_mcast_flags_dump_entry(struct sk_buff *msg, u32 portid,
			      struct netlink_callback *cb,
			      struct batadv_orig_node *orig_node)
{
	void *hdr;

	hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
			  &batadv_netlink_family, NLM_F_MULTI,
			  BATADV_CMD_GET_MCAST_FLAGS);
	if (!hdr)
		return -ENOBUFS;

	genl_dump_check_consistent(cb, hdr);

	if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
		    orig_node->orig)) {
		genlmsg_cancel(msg, hdr);
		return -EMSGSIZE;
	}

	if (test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
		     &orig_node->capabilities)) {
		if (nla_put_u32(msg, BATADV_ATTR_MCAST_FLAGS,
				orig_node->mcast_flags)) {
			genlmsg_cancel(msg, hdr);
			return -EMSGSIZE;
		}
	}

	genlmsg_end(msg, hdr);
	return 0;
}

/**
 * batadv_mcast_flags_dump_bucket() - dump one bucket of the multicast flags
 *  table to a netlink socket
 * @msg: buffer for the message
 * @portid: netlink port
 * @cb: Control block containing additional options
 * @hash: hash to dump
 * @bucket: bucket index to dump
 * @idx_skip: How many entries to skip
 *
 * Return: 0 or error code.
 */
static int
batadv_mcast_flags_dump_bucket(struct sk_buff *msg, u32 portid,
			       struct netlink_callback *cb,
			       struct batadv_hashtable *hash,
			       unsigned int bucket, long *idx_skip)
{
	struct batadv_orig_node *orig_node;
	long idx = 0;

	spin_lock_bh(&hash->list_locks[bucket]);
	cb->seq = atomic_read(&hash->generation) << 1 | 1;

	hlist_for_each_entry(orig_node, &hash->table[bucket], hash_entry) {
		if (!test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
			      &orig_node->capa_initialized))
			continue;

		if (idx < *idx_skip)
			goto skip;

		if (batadv_mcast_flags_dump_entry(msg, portid, cb, orig_node)) {
			spin_unlock_bh(&hash->list_locks[bucket]);
			*idx_skip = idx;

			return -EMSGSIZE;
		}

skip:
		idx++;
	}
	spin_unlock_bh(&hash->list_locks[bucket]);

	return 0;
}

/**
 * __batadv_mcast_flags_dump() - dump multicast flags table to a netlink socket
 * @msg: buffer for the message
 * @portid: netlink port
 * @cb: Control block containing additional options
 * @bat_priv: the bat priv with all the soft interface information
 * @bucket: current bucket to dump
 * @idx: index in current bucket to the next entry to dump
 *
 * Return: 0 or error code.
 */
static int
__batadv_mcast_flags_dump(struct sk_buff *msg, u32 portid,
			  struct netlink_callback *cb,
			  struct batadv_priv *bat_priv, long *bucket, long *idx)
{
	struct batadv_hashtable *hash = bat_priv->orig_hash;
	long bucket_tmp = *bucket;
	long idx_tmp = *idx;

	while (bucket_tmp < hash->size) {
		if (batadv_mcast_flags_dump_bucket(msg, portid, cb, hash,
						   bucket_tmp, &idx_tmp))
			break;

		bucket_tmp++;
		idx_tmp = 0;
	}

	*bucket = bucket_tmp;
	*idx = idx_tmp;

	return msg->len;
}

/**
 * batadv_mcast_netlink_get_primary() - get primary interface from netlink
 *  callback
 * @cb: netlink callback structure
 * @primary_if: the primary interface pointer to return the result in
 *
 * Return: 0 or error code.
 */
static int
batadv_mcast_netlink_get_primary(struct netlink_callback *cb,
				 struct batadv_hard_iface **primary_if)
{
	struct batadv_hard_iface *hard_iface = NULL;
	struct net *net = sock_net(cb->skb->sk);
	struct net_device *soft_iface;
	struct batadv_priv *bat_priv;
	int ifindex;
	int ret = 0;

	ifindex = batadv_netlink_get_ifindex(cb->nlh, BATADV_ATTR_MESH_IFINDEX);
	if (!ifindex)
		return -EINVAL;

	soft_iface = dev_get_by_index(net, ifindex);
	if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
		ret = -ENODEV;
		goto out;
	}

	bat_priv = netdev_priv(soft_iface);

	hard_iface = batadv_primary_if_get_selected(bat_priv);
	if (!hard_iface || hard_iface->if_status != BATADV_IF_ACTIVE) {
		ret = -ENOENT;
		goto out;
	}

out:
	if (soft_iface)
		dev_put(soft_iface);

	if (!ret && primary_if)
		*primary_if = hard_iface;
	else if (hard_iface)
		batadv_hardif_put(hard_iface);

	return ret;
}

/**
 * batadv_mcast_flags_dump() - dump multicast flags table to a netlink socket
 * @msg: buffer for the message
 * @cb: callback structure containing arguments
 *
 * Return: message length.
 */
int batadv_mcast_flags_dump(struct sk_buff *msg, struct netlink_callback *cb)
{
	struct batadv_hard_iface *primary_if = NULL;
	int portid = NETLINK_CB(cb->skb).portid;
	struct batadv_priv *bat_priv;
	long *bucket = &cb->args[0];
	long *idx = &cb->args[1];
	int ret;

	ret = batadv_mcast_netlink_get_primary(cb, &primary_if);
	if (ret)
		return ret;

	bat_priv = netdev_priv(primary_if->soft_iface);
	ret = __batadv_mcast_flags_dump(msg, portid, cb, bat_priv, bucket, idx);

	batadv_hardif_put(primary_if);
	return ret;
}

/**
 * batadv_mcast_free() - free the multicast optimizations structures
 * @bat_priv: the bat priv with all the soft interface information
 */
void batadv_mcast_free(struct batadv_priv *bat_priv)
{
	cancel_delayed_work_sync(&bat_priv->mcast.work);

	batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_MCAST, 2);
	batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_MCAST, 2);

	/* safely calling outside of worker, as worker was canceled above */
	batadv_mcast_mla_tt_retract(bat_priv, NULL);
}

/**
 * batadv_mcast_purge_orig() - reset originator global mcast state modifications
 * @orig: the originator which is going to get purged
 */
void batadv_mcast_purge_orig(struct batadv_orig_node *orig)
{
	struct batadv_priv *bat_priv = orig->bat_priv;

	spin_lock_bh(&orig->mcast_handler_lock);

	batadv_mcast_want_unsnoop_update(bat_priv, orig, BATADV_NO_FLAGS);
	batadv_mcast_want_ipv4_update(bat_priv, orig, BATADV_NO_FLAGS);
	batadv_mcast_want_ipv6_update(bat_priv, orig, BATADV_NO_FLAGS);
	batadv_mcast_want_rtr4_update(bat_priv, orig,
				      BATADV_MCAST_WANT_NO_RTR4);
	batadv_mcast_want_rtr6_update(bat_priv, orig,
				      BATADV_MCAST_WANT_NO_RTR6);

	spin_unlock_bh(&orig->mcast_handler_lock);
}