summaryrefslogtreecommitdiffstats
path: root/net/batman-adv/translation-table.c
blob: b4824951010ba6b42bf7d7c7eb62c529ed340158 (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
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
/* Copyright (C) 2007-2015 B.A.T.M.A.N. contributors:
 *
 * Marek Lindner, Simon Wunderlich, Antonio Quartulli
 *
 * 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 "translation-table.h"
#include "main.h"

#include <linux/atomic.h>
#include <linux/bug.h>
#include <linux/byteorder/generic.h>
#include <linux/compiler.h>
#include <linux/crc32c.h>
#include <linux/errno.h>
#include <linux/etherdevice.h>
#include <linux/fs.h>
#include <linux/if_ether.h>
#include <linux/jhash.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/lockdep.h>
#include <linux/netdevice.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <linux/workqueue.h>
#include <net/net_namespace.h>

#include "bridge_loop_avoidance.h"
#include "hard-interface.h"
#include "hash.h"
#include "multicast.h"
#include "originator.h"
#include "packet.h"
#include "soft-interface.h"

/* hash class keys */
static struct lock_class_key batadv_tt_local_hash_lock_class_key;
static struct lock_class_key batadv_tt_global_hash_lock_class_key;

static void batadv_send_roam_adv(struct batadv_priv *bat_priv, uint8_t *client,
				 unsigned short vid,
				 struct batadv_orig_node *orig_node);
static void batadv_tt_purge(struct work_struct *work);
static void
batadv_tt_global_del_orig_list(struct batadv_tt_global_entry *tt_global_entry);
static void batadv_tt_global_del(struct batadv_priv *bat_priv,
				 struct batadv_orig_node *orig_node,
				 const unsigned char *addr,
				 unsigned short vid, const char *message,
				 bool roaming);

/* returns 1 if they are the same mac addr */
static int batadv_compare_tt(const struct hlist_node *node, const void *data2)
{
	const void *data1 = container_of(node, struct batadv_tt_common_entry,
					 hash_entry);

	return batadv_compare_eth(data1, data2);
}

/**
 * batadv_choose_tt - return the index of the tt entry in the hash table
 * @data: pointer to the tt_common_entry object to map
 * @size: the size of the hash table
 *
 * Returns the hash index where the object represented by 'data' should be
 * stored at.
 */
static inline uint32_t batadv_choose_tt(const void *data, uint32_t size)
{
	struct batadv_tt_common_entry *tt;
	uint32_t hash = 0;

	tt = (struct batadv_tt_common_entry *)data;
	hash = jhash(&tt->addr, ETH_ALEN, hash);
	hash = jhash(&tt->vid, sizeof(tt->vid), hash);

	return hash % size;
}

/**
 * batadv_tt_hash_find - look for a client in the given hash table
 * @hash: the hash table to search
 * @addr: the mac address of the client to look for
 * @vid: VLAN identifier
 *
 * Returns a pointer to the tt_common struct belonging to the searched client if
 * found, NULL otherwise.
 */
static struct batadv_tt_common_entry *
batadv_tt_hash_find(struct batadv_hashtable *hash, const uint8_t *addr,
		    unsigned short vid)
{
	struct hlist_head *head;
	struct batadv_tt_common_entry to_search, *tt, *tt_tmp = NULL;
	uint32_t index;

	if (!hash)
		return NULL;

	ether_addr_copy(to_search.addr, addr);
	to_search.vid = vid;

	index = batadv_choose_tt(&to_search, hash->size);
	head = &hash->table[index];

	rcu_read_lock();
	hlist_for_each_entry_rcu(tt, head, hash_entry) {
		if (!batadv_compare_eth(tt, addr))
			continue;

		if (tt->vid != vid)
			continue;

		if (!atomic_inc_not_zero(&tt->refcount))
			continue;

		tt_tmp = tt;
		break;
	}
	rcu_read_unlock();

	return tt_tmp;
}

/**
 * batadv_tt_local_hash_find - search the local table for a given client
 * @bat_priv: the bat priv with all the soft interface information
 * @addr: the mac address of the client to look for
 * @vid: VLAN identifier
 *
 * Returns a pointer to the corresponding tt_local_entry struct if the client is
 * found, NULL otherwise.
 */
static struct batadv_tt_local_entry *
batadv_tt_local_hash_find(struct batadv_priv *bat_priv, const uint8_t *addr,
			  unsigned short vid)
{
	struct batadv_tt_common_entry *tt_common_entry;
	struct batadv_tt_local_entry *tt_local_entry = NULL;

	tt_common_entry = batadv_tt_hash_find(bat_priv->tt.local_hash, addr,
					      vid);
	if (tt_common_entry)
		tt_local_entry = container_of(tt_common_entry,
					      struct batadv_tt_local_entry,
					      common);
	return tt_local_entry;
}

/**
 * batadv_tt_global_hash_find - search the global table for a given client
 * @bat_priv: the bat priv with all the soft interface information
 * @addr: the mac address of the client to look for
 * @vid: VLAN identifier
 *
 * Returns a pointer to the corresponding tt_global_entry struct if the client
 * is found, NULL otherwise.
 */
static struct batadv_tt_global_entry *
batadv_tt_global_hash_find(struct batadv_priv *bat_priv, const uint8_t *addr,
			   unsigned short vid)
{
	struct batadv_tt_common_entry *tt_common_entry;
	struct batadv_tt_global_entry *tt_global_entry = NULL;

	tt_common_entry = batadv_tt_hash_find(bat_priv->tt.global_hash, addr,
					      vid);
	if (tt_common_entry)
		tt_global_entry = container_of(tt_common_entry,
					       struct batadv_tt_global_entry,
					       common);
	return tt_global_entry;
}

static void
batadv_tt_local_entry_free_ref(struct batadv_tt_local_entry *tt_local_entry)
{
	if (atomic_dec_and_test(&tt_local_entry->common.refcount))
		kfree_rcu(tt_local_entry, common.rcu);
}

/**
 * batadv_tt_global_entry_free_ref - decrement the refcounter for a
 *  tt_global_entry and possibly free it
 * @tt_global_entry: the object to free
 */
static void
batadv_tt_global_entry_free_ref(struct batadv_tt_global_entry *tt_global_entry)
{
	if (atomic_dec_and_test(&tt_global_entry->common.refcount)) {
		batadv_tt_global_del_orig_list(tt_global_entry);
		kfree_rcu(tt_global_entry, common.rcu);
	}
}

/**
 * batadv_tt_global_hash_count - count the number of orig entries
 * @hash: hash table containing the tt entries
 * @addr: the mac address of the client to count entries for
 * @vid: VLAN identifier
 *
 * Return the number of originators advertising the given address/data
 * (excluding ourself).
 */
int batadv_tt_global_hash_count(struct batadv_priv *bat_priv,
				const uint8_t *addr, unsigned short vid)
{
	struct batadv_tt_global_entry *tt_global_entry;
	int count;

	tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr, vid);
	if (!tt_global_entry)
		return 0;

	count = atomic_read(&tt_global_entry->orig_list_count);
	batadv_tt_global_entry_free_ref(tt_global_entry);

	return count;
}

static void batadv_tt_orig_list_entry_free_rcu(struct rcu_head *rcu)
{
	struct batadv_tt_orig_list_entry *orig_entry;

	orig_entry = container_of(rcu, struct batadv_tt_orig_list_entry, rcu);

	/* We are in an rcu callback here, therefore we cannot use
	 * batadv_orig_node_free_ref() and its call_rcu():
	 * An rcu_barrier() wouldn't wait for that to finish
	 */
	batadv_orig_node_free_ref_now(orig_entry->orig_node);
	kfree(orig_entry);
}

/**
 * batadv_tt_local_size_mod - change the size by v of the local table identified
 *  by vid
 * @bat_priv: the bat priv with all the soft interface information
 * @vid: the VLAN identifier of the sub-table to change
 * @v: the amount to sum to the local table size
 */
static void batadv_tt_local_size_mod(struct batadv_priv *bat_priv,
				     unsigned short vid, int v)
{
	struct batadv_softif_vlan *vlan;

	vlan = batadv_softif_vlan_get(bat_priv, vid);
	if (!vlan)
		return;

	atomic_add(v, &vlan->tt.num_entries);

	batadv_softif_vlan_free_ref(vlan);
}

/**
 * batadv_tt_local_size_inc - increase by one the local table size for the given
 *  vid
 * @bat_priv: the bat priv with all the soft interface information
 * @vid: the VLAN identifier
 */
static void batadv_tt_local_size_inc(struct batadv_priv *bat_priv,
				     unsigned short vid)
{
	batadv_tt_local_size_mod(bat_priv, vid, 1);
}

/**
 * batadv_tt_local_size_dec - decrease by one the local table size for the given
 *  vid
 * @bat_priv: the bat priv with all the soft interface information
 * @vid: the VLAN identifier
 */
static void batadv_tt_local_size_dec(struct batadv_priv *bat_priv,
				     unsigned short vid)
{
	batadv_tt_local_size_mod(bat_priv, vid, -1);
}

/**
 * batadv_tt_global_size_mod - change the size by v of the local table
 *  identified by vid
 * @bat_priv: the bat priv with all the soft interface information
 * @vid: the VLAN identifier
 * @v: the amount to sum to the global table size
 */
static void batadv_tt_global_size_mod(struct batadv_orig_node *orig_node,
				      unsigned short vid, int v)
{
	struct batadv_orig_node_vlan *vlan;

	vlan = batadv_orig_node_vlan_new(orig_node, vid);
	if (!vlan)
		return;

	if (atomic_add_return(v, &vlan->tt.num_entries) == 0) {
		spin_lock_bh(&orig_node->vlan_list_lock);
		list_del_rcu(&vlan->list);
		spin_unlock_bh(&orig_node->vlan_list_lock);
		batadv_orig_node_vlan_free_ref(vlan);
	}

	batadv_orig_node_vlan_free_ref(vlan);
}

/**
 * batadv_tt_global_size_inc - increase by one the global table size for the
 *  given vid
 * @orig_node: the originator which global table size has to be decreased
 * @vid: the vlan identifier
 */
static void batadv_tt_global_size_inc(struct batadv_orig_node *orig_node,
				      unsigned short vid)
{
	batadv_tt_global_size_mod(orig_node, vid, 1);
}

/**
 * batadv_tt_global_size_dec - decrease by one the global table size for the
 *  given vid
 * @orig_node: the originator which global table size has to be decreased
 * @vid: the vlan identifier
 */
static void batadv_tt_global_size_dec(struct batadv_orig_node *orig_node,
				      unsigned short vid)
{
	batadv_tt_global_size_mod(orig_node, vid, -1);
}

static void
batadv_tt_orig_list_entry_free_ref(struct batadv_tt_orig_list_entry *orig_entry)
{
	if (!atomic_dec_and_test(&orig_entry->refcount))
		return;

	call_rcu(&orig_entry->rcu, batadv_tt_orig_list_entry_free_rcu);
}

/**
 * batadv_tt_local_event - store a local TT event (ADD/DEL)
 * @bat_priv: the bat priv with all the soft interface information
 * @tt_local_entry: the TT entry involved in the event
 * @event_flags: flags to store in the event structure
 */
static void batadv_tt_local_event(struct batadv_priv *bat_priv,
				  struct batadv_tt_local_entry *tt_local_entry,
				  uint8_t event_flags)
{
	struct batadv_tt_change_node *tt_change_node, *entry, *safe;
	struct batadv_tt_common_entry *common = &tt_local_entry->common;
	uint8_t flags = common->flags | event_flags;
	bool event_removed = false;
	bool del_op_requested, del_op_entry;

	tt_change_node = kmalloc(sizeof(*tt_change_node), GFP_ATOMIC);
	if (!tt_change_node)
		return;

	tt_change_node->change.flags = flags;
	memset(tt_change_node->change.reserved, 0,
	       sizeof(tt_change_node->change.reserved));
	ether_addr_copy(tt_change_node->change.addr, common->addr);
	tt_change_node->change.vid = htons(common->vid);

	del_op_requested = flags & BATADV_TT_CLIENT_DEL;

	/* check for ADD+DEL or DEL+ADD events */
	spin_lock_bh(&bat_priv->tt.changes_list_lock);
	list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
				 list) {
		if (!batadv_compare_eth(entry->change.addr, common->addr))
			continue;

		/* DEL+ADD in the same orig interval have no effect and can be
		 * removed to avoid silly behaviour on the receiver side. The
		 * other way around (ADD+DEL) can happen in case of roaming of
		 * a client still in the NEW state. Roaming of NEW clients is
		 * now possible due to automatically recognition of "temporary"
		 * clients
		 */
		del_op_entry = entry->change.flags & BATADV_TT_CLIENT_DEL;
		if (!del_op_requested && del_op_entry)
			goto del;
		if (del_op_requested && !del_op_entry)
			goto del;

		/* this is a second add in the same originator interval. It
		 * means that flags have been changed: update them!
		 */
		if (!del_op_requested && !del_op_entry)
			entry->change.flags = flags;

		continue;
del:
		list_del(&entry->list);
		kfree(entry);
		kfree(tt_change_node);
		event_removed = true;
		goto unlock;
	}

	/* track the change in the OGMinterval list */
	list_add_tail(&tt_change_node->list, &bat_priv->tt.changes_list);

unlock:
	spin_unlock_bh(&bat_priv->tt.changes_list_lock);

	if (event_removed)
		atomic_dec(&bat_priv->tt.local_changes);
	else
		atomic_inc(&bat_priv->tt.local_changes);
}

/**
 * batadv_tt_len - compute length in bytes of given number of tt changes
 * @changes_num: number of tt changes
 *
 * Returns computed length in bytes.
 */
static int batadv_tt_len(int changes_num)
{
	return changes_num * sizeof(struct batadv_tvlv_tt_change);
}

/**
 * batadv_tt_entries - compute the number of entries fitting in tt_len bytes
 * @tt_len: available space
 *
 * Returns the number of entries.
 */
static uint16_t batadv_tt_entries(uint16_t tt_len)
{
	return tt_len / batadv_tt_len(1);
}

/**
 * batadv_tt_local_table_transmit_size - calculates the local translation table
 *  size when transmitted over the air
 * @bat_priv: the bat priv with all the soft interface information
 *
 * Returns local translation table size in bytes.
 */
static int batadv_tt_local_table_transmit_size(struct batadv_priv *bat_priv)
{
	uint16_t num_vlan = 0, tt_local_entries = 0;
	struct batadv_softif_vlan *vlan;
	int hdr_size;

	rcu_read_lock();
	hlist_for_each_entry_rcu(vlan, &bat_priv->softif_vlan_list, list) {
		num_vlan++;
		tt_local_entries += atomic_read(&vlan->tt.num_entries);
	}
	rcu_read_unlock();

	/* header size of tvlv encapsulated tt response payload */
	hdr_size = sizeof(struct batadv_unicast_tvlv_packet);
	hdr_size += sizeof(struct batadv_tvlv_hdr);
	hdr_size += sizeof(struct batadv_tvlv_tt_data);
	hdr_size += num_vlan * sizeof(struct batadv_tvlv_tt_vlan_data);

	return hdr_size + batadv_tt_len(tt_local_entries);
}

static int batadv_tt_local_init(struct batadv_priv *bat_priv)
{
	if (bat_priv->tt.local_hash)
		return 0;

	bat_priv->tt.local_hash = batadv_hash_new(1024);

	if (!bat_priv->tt.local_hash)
		return -ENOMEM;

	batadv_hash_set_lock_class(bat_priv->tt.local_hash,
				   &batadv_tt_local_hash_lock_class_key);

	return 0;
}

static void batadv_tt_global_free(struct batadv_priv *bat_priv,
				  struct batadv_tt_global_entry *tt_global,
				  const char *message)
{
	batadv_dbg(BATADV_DBG_TT, bat_priv,
		   "Deleting global tt entry %pM (vid: %d): %s\n",
		   tt_global->common.addr,
		   BATADV_PRINT_VID(tt_global->common.vid), message);

	batadv_hash_remove(bat_priv->tt.global_hash, batadv_compare_tt,
			   batadv_choose_tt, &tt_global->common);
	batadv_tt_global_entry_free_ref(tt_global);
}

/**
 * batadv_tt_local_add - add a new client to the local table or update an
 *  existing client
 * @soft_iface: netdev struct of the mesh interface
 * @addr: the mac address of the client to add
 * @vid: VLAN identifier
 * @ifindex: index of the interface where the client is connected to (useful to
 *  identify wireless clients)
 * @mark: the value contained in the skb->mark field of the received packet (if
 *  any)
 *
 * Returns true if the client was successfully added, false otherwise.
 */
bool batadv_tt_local_add(struct net_device *soft_iface, const uint8_t *addr,
			 unsigned short vid, int ifindex, uint32_t mark)
{
	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
	struct batadv_tt_local_entry *tt_local;
	struct batadv_tt_global_entry *tt_global = NULL;
	struct batadv_softif_vlan *vlan;
	struct net_device *in_dev = NULL;
	struct hlist_head *head;
	struct batadv_tt_orig_list_entry *orig_entry;
	int hash_added, table_size, packet_size_max;
	bool ret = false, roamed_back = false;
	uint8_t remote_flags;
	uint32_t match_mark;

	if (ifindex != BATADV_NULL_IFINDEX)
		in_dev = dev_get_by_index(&init_net, ifindex);

	tt_local = batadv_tt_local_hash_find(bat_priv, addr, vid);

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

	if (tt_local) {
		tt_local->last_seen = jiffies;
		if (tt_local->common.flags & BATADV_TT_CLIENT_PENDING) {
			batadv_dbg(BATADV_DBG_TT, bat_priv,
				   "Re-adding pending client %pM (vid: %d)\n",
				   addr, BATADV_PRINT_VID(vid));
			/* whatever the reason why the PENDING flag was set,
			 * this is a client which was enqueued to be removed in
			 * this orig_interval. Since it popped up again, the
			 * flag can be reset like it was never enqueued
			 */
			tt_local->common.flags &= ~BATADV_TT_CLIENT_PENDING;
			goto add_event;
		}

		if (tt_local->common.flags & BATADV_TT_CLIENT_ROAM) {
			batadv_dbg(BATADV_DBG_TT, bat_priv,
				   "Roaming client %pM (vid: %d) came back to its original location\n",
				   addr, BATADV_PRINT_VID(vid));
			/* the ROAM flag is set because this client roamed away
			 * and the node got a roaming_advertisement message. Now
			 * that the client popped up again at its original
			 * location such flag can be unset
			 */
			tt_local->common.flags &= ~BATADV_TT_CLIENT_ROAM;
			roamed_back = true;
		}
		goto check_roaming;
	}

	/* Ignore the client if we cannot send it in a full table response. */
	table_size = batadv_tt_local_table_transmit_size(bat_priv);
	table_size += batadv_tt_len(1);
	packet_size_max = atomic_read(&bat_priv->packet_size_max);
	if (table_size > packet_size_max) {
		net_ratelimited_function(batadv_info, soft_iface,
					 "Local translation table size (%i) exceeds maximum packet size (%i); Ignoring new local tt entry: %pM\n",
					 table_size, packet_size_max, addr);
		goto out;
	}

	tt_local = kmalloc(sizeof(*tt_local), GFP_ATOMIC);
	if (!tt_local)
		goto out;

	/* increase the refcounter of the related vlan */
	vlan = batadv_softif_vlan_get(bat_priv, vid);

	batadv_dbg(BATADV_DBG_TT, bat_priv,
		   "Creating new local tt entry: %pM (vid: %d, ttvn: %d)\n",
		   addr, BATADV_PRINT_VID(vid),
		   (uint8_t)atomic_read(&bat_priv->tt.vn));

	ether_addr_copy(tt_local->common.addr, addr);
	/* The local entry has to be marked as NEW to avoid to send it in
	 * a full table response going out before the next ttvn increment
	 * (consistency check)
	 */
	tt_local->common.flags = BATADV_TT_CLIENT_NEW;
	tt_local->common.vid = vid;
	if (batadv_is_wifi_netdev(in_dev))
		tt_local->common.flags |= BATADV_TT_CLIENT_WIFI;
	atomic_set(&tt_local->common.refcount, 2);
	tt_local->last_seen = jiffies;
	tt_local->common.added_at = tt_local->last_seen;

	/* the batman interface mac and multicast addresses should never be
	 * purged
	 */
	if (batadv_compare_eth(addr, soft_iface->dev_addr) ||
	    is_multicast_ether_addr(addr))
		tt_local->common.flags |= BATADV_TT_CLIENT_NOPURGE;

	hash_added = batadv_hash_add(bat_priv->tt.local_hash, batadv_compare_tt,
				     batadv_choose_tt, &tt_local->common,
				     &tt_local->common.hash_entry);

	if (unlikely(hash_added != 0)) {
		/* remove the reference for the hash */
		batadv_tt_local_entry_free_ref(tt_local);
		batadv_softif_vlan_free_ref(vlan);
		goto out;
	}

add_event:
	batadv_tt_local_event(bat_priv, tt_local, BATADV_NO_FLAGS);

check_roaming:
	/* Check whether it is a roaming, but don't do anything if the roaming
	 * process has already been handled
	 */
	if (tt_global && !(tt_global->common.flags & BATADV_TT_CLIENT_ROAM)) {
		/* These node are probably going to update their tt table */
		head = &tt_global->orig_list;
		rcu_read_lock();
		hlist_for_each_entry_rcu(orig_entry, head, list) {
			batadv_send_roam_adv(bat_priv, tt_global->common.addr,
					     tt_global->common.vid,
					     orig_entry->orig_node);
		}
		rcu_read_unlock();
		if (roamed_back) {
			batadv_tt_global_free(bat_priv, tt_global,
					      "Roaming canceled");
			tt_global = NULL;
		} else {
			/* The global entry has to be marked as ROAMING and
			 * has to be kept for consistency purpose
			 */
			tt_global->common.flags |= BATADV_TT_CLIENT_ROAM;
			tt_global->roam_at = jiffies;
		}
	}

	/* store the current remote flags before altering them. This helps
	 * understanding is flags are changing or not
	 */
	remote_flags = tt_local->common.flags & BATADV_TT_REMOTE_MASK;

	if (batadv_is_wifi_netdev(in_dev))
		tt_local->common.flags |= BATADV_TT_CLIENT_WIFI;
	else
		tt_local->common.flags &= ~BATADV_TT_CLIENT_WIFI;

	/* check the mark in the skb: if it's equal to the configured
	 * isolation_mark, it means the packet is coming from an isolated
	 * non-mesh client
	 */
	match_mark = (mark & bat_priv->isolation_mark_mask);
	if (bat_priv->isolation_mark_mask &&
	    match_mark == bat_priv->isolation_mark)
		tt_local->common.flags |= BATADV_TT_CLIENT_ISOLA;
	else
		tt_local->common.flags &= ~BATADV_TT_CLIENT_ISOLA;

	/* if any "dynamic" flag has been modified, resend an ADD event for this
	 * entry so that all the nodes can get the new flags
	 */
	if (remote_flags ^ (tt_local->common.flags & BATADV_TT_REMOTE_MASK))
		batadv_tt_local_event(bat_priv, tt_local, BATADV_NO_FLAGS);

	ret = true;
out:
	if (in_dev)
		dev_put(in_dev);
	if (tt_local)
		batadv_tt_local_entry_free_ref(tt_local);
	if (tt_global)
		batadv_tt_global_entry_free_ref(tt_global);
	return ret;
}

/**
 * batadv_tt_prepare_tvlv_global_data - prepare the TVLV TT header to send
 *  within a TT Response directed to another node
 * @orig_node: originator for which the TT data has to be prepared
 * @tt_data: uninitialised pointer to the address of the TVLV buffer
 * @tt_change: uninitialised pointer to the address of the area where the TT
 *  changed can be stored
 * @tt_len: pointer to the length to reserve to the tt_change. if -1 this
 *  function reserves the amount of space needed to send the entire global TT
 *  table. In case of success the value is updated with the real amount of
 *  reserved bytes

 * Allocate the needed amount of memory for the entire TT TVLV and write its
 * header made up by one tvlv_tt_data object and a series of tvlv_tt_vlan_data
 * objects, one per active VLAN served by the originator node.
 *
 * Return the size of the allocated buffer or 0 in case of failure.
 */
static uint16_t
batadv_tt_prepare_tvlv_global_data(struct batadv_orig_node *orig_node,
				   struct batadv_tvlv_tt_data **tt_data,
				   struct batadv_tvlv_tt_change **tt_change,
				   int32_t *tt_len)
{
	uint16_t num_vlan = 0, num_entries = 0, change_offset, tvlv_len;
	struct batadv_tvlv_tt_vlan_data *tt_vlan;
	struct batadv_orig_node_vlan *vlan;
	uint8_t *tt_change_ptr;

	rcu_read_lock();
	list_for_each_entry_rcu(vlan, &orig_node->vlan_list, list) {
		num_vlan++;
		num_entries += atomic_read(&vlan->tt.num_entries);
	}

	change_offset = sizeof(**tt_data);
	change_offset += num_vlan * sizeof(*tt_vlan);

	/* if tt_len is negative, allocate the space needed by the full table */
	if (*tt_len < 0)
		*tt_len = batadv_tt_len(num_entries);

	tvlv_len = *tt_len;
	tvlv_len += change_offset;

	*tt_data = kmalloc(tvlv_len, GFP_ATOMIC);
	if (!*tt_data) {
		*tt_len = 0;
		goto out;
	}

	(*tt_data)->flags = BATADV_NO_FLAGS;
	(*tt_data)->ttvn = atomic_read(&orig_node->last_ttvn);
	(*tt_data)->num_vlan = htons(num_vlan);

	tt_vlan = (struct batadv_tvlv_tt_vlan_data *)(*tt_data + 1);
	list_for_each_entry_rcu(vlan, &orig_node->vlan_list, list) {
		tt_vlan->vid = htons(vlan->vid);
		tt_vlan->crc = htonl(vlan->tt.crc);

		tt_vlan++;
	}

	tt_change_ptr = (uint8_t *)*tt_data + change_offset;
	*tt_change = (struct batadv_tvlv_tt_change *)tt_change_ptr;

out:
	rcu_read_unlock();
	return tvlv_len;
}

/**
 * batadv_tt_prepare_tvlv_local_data - allocate and prepare the TT TVLV for this
 *  node
 * @bat_priv: the bat priv with all the soft interface information
 * @tt_data: uninitialised pointer to the address of the TVLV buffer
 * @tt_change: uninitialised pointer to the address of the area where the TT
 *  changes can be stored
 * @tt_len: pointer to the length to reserve to the tt_change. if -1 this
 *  function reserves the amount of space needed to send the entire local TT
 *  table. In case of success the value is updated with the real amount of
 *  reserved bytes
 *
 * Allocate the needed amount of memory for the entire TT TVLV and write its
 * header made up by one tvlv_tt_data object and a series of tvlv_tt_vlan_data
 * objects, one per active VLAN.
 *
 * Return the size of the allocated buffer or 0 in case of failure.
 */
static uint16_t
batadv_tt_prepare_tvlv_local_data(struct batadv_priv *bat_priv,
				  struct batadv_tvlv_tt_data **tt_data,
				  struct batadv_tvlv_tt_change **tt_change,
				  int32_t *tt_len)
{
	struct batadv_tvlv_tt_vlan_data *tt_vlan;
	struct batadv_softif_vlan *vlan;
	uint16_t num_vlan = 0, num_entries = 0, tvlv_len;
	uint8_t *tt_change_ptr;
	int change_offset;

	rcu_read_lock();
	hlist_for_each_entry_rcu(vlan, &bat_priv->softif_vlan_list, list) {
		num_vlan++;
		num_entries += atomic_read(&vlan->tt.num_entries);
	}

	change_offset = sizeof(**tt_data);
	change_offset += num_vlan * sizeof(*tt_vlan);

	/* if tt_len is negative, allocate the space needed by the full table */
	if (*tt_len < 0)
		*tt_len = batadv_tt_len(num_entries);

	tvlv_len = *tt_len;
	tvlv_len += change_offset;

	*tt_data = kmalloc(tvlv_len, GFP_ATOMIC);
	if (!*tt_data) {
		tvlv_len = 0;
		goto out;
	}

	(*tt_data)->flags = BATADV_NO_FLAGS;
	(*tt_data)->ttvn = atomic_read(&bat_priv->tt.vn);
	(*tt_data)->num_vlan = htons(num_vlan);

	tt_vlan = (struct batadv_tvlv_tt_vlan_data *)(*tt_data + 1);
	hlist_for_each_entry_rcu(vlan, &bat_priv->softif_vlan_list, list) {
		tt_vlan->vid = htons(vlan->vid);
		tt_vlan->crc = htonl(vlan->tt.crc);

		tt_vlan++;
	}

	tt_change_ptr = (uint8_t *)*tt_data + change_offset;
	*tt_change = (struct batadv_tvlv_tt_change *)tt_change_ptr;

out:
	rcu_read_unlock();
	return tvlv_len;
}

/**
 * batadv_tt_tvlv_container_update - update the translation table tvlv container
 *  after local tt changes have been committed
 * @bat_priv: the bat priv with all the soft interface information
 */
static void batadv_tt_tvlv_container_update(struct batadv_priv *bat_priv)
{
	struct batadv_tt_change_node *entry, *safe;
	struct batadv_tvlv_tt_data *tt_data;
	struct batadv_tvlv_tt_change *tt_change;
	int tt_diff_len, tt_change_len = 0;
	int tt_diff_entries_num = 0, tt_diff_entries_count = 0;
	uint16_t tvlv_len;

	tt_diff_entries_num = atomic_read(&bat_priv->tt.local_changes);
	tt_diff_len = batadv_tt_len(tt_diff_entries_num);

	/* if we have too many changes for one packet don't send any
	 * and wait for the tt table request which will be fragmented
	 */
	if (tt_diff_len > bat_priv->soft_iface->mtu)
		tt_diff_len = 0;

	tvlv_len = batadv_tt_prepare_tvlv_local_data(bat_priv, &tt_data,
						     &tt_change, &tt_diff_len);
	if (!tvlv_len)
		return;

	tt_data->flags = BATADV_TT_OGM_DIFF;

	if (tt_diff_len == 0)
		goto container_register;

	spin_lock_bh(&bat_priv->tt.changes_list_lock);
	atomic_set(&bat_priv->tt.local_changes, 0);

	list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
				 list) {
		if (tt_diff_entries_count < tt_diff_entries_num) {
			memcpy(tt_change + tt_diff_entries_count,
			       &entry->change,
			       sizeof(struct batadv_tvlv_tt_change));
			tt_diff_entries_count++;
		}
		list_del(&entry->list);
		kfree(entry);
	}
	spin_unlock_bh(&bat_priv->tt.changes_list_lock);

	/* Keep the buffer for possible tt_request */
	spin_lock_bh(&bat_priv->tt.last_changeset_lock);
	kfree(bat_priv->tt.last_changeset);
	bat_priv->tt.last_changeset_len = 0;
	bat_priv->tt.last_changeset = NULL;
	tt_change_len = batadv_tt_len(tt_diff_entries_count);
	/* check whether this new OGM has no changes due to size problems */
	if (tt_diff_entries_count > 0) {
		/* if kmalloc() fails we will reply with the full table
		 * instead of providing the diff
		 */
		bat_priv->tt.last_changeset = kzalloc(tt_diff_len, GFP_ATOMIC);
		if (bat_priv->tt.last_changeset) {
			memcpy(bat_priv->tt.last_changeset,
			       tt_change, tt_change_len);
			bat_priv->tt.last_changeset_len = tt_diff_len;
		}
	}
	spin_unlock_bh(&bat_priv->tt.last_changeset_lock);

container_register:
	batadv_tvlv_container_register(bat_priv, BATADV_TVLV_TT, 1, tt_data,
				       tvlv_len);
	kfree(tt_data);
}

int batadv_tt_local_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_hashtable *hash = bat_priv->tt.local_hash;
	struct batadv_tt_common_entry *tt_common_entry;
	struct batadv_tt_local_entry *tt_local;
	struct batadv_hard_iface *primary_if;
	struct batadv_softif_vlan *vlan;
	struct hlist_head *head;
	unsigned short vid;
	uint32_t i;
	int last_seen_secs;
	int last_seen_msecs;
	unsigned long last_seen_jiffies;
	bool no_purge;
	uint16_t np_flag = BATADV_TT_CLIENT_NOPURGE;

	primary_if = batadv_seq_print_text_primary_if_get(seq);
	if (!primary_if)
		goto out;

	seq_printf(seq,
		   "Locally retrieved addresses (from %s) announced via TT (TTVN: %u):\n",
		   net_dev->name, (uint8_t)atomic_read(&bat_priv->tt.vn));
	seq_printf(seq, "       %-13s  %s %-8s %-9s (%-10s)\n", "Client", "VID",
		   "Flags", "Last seen", "CRC");

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

		rcu_read_lock();
		hlist_for_each_entry_rcu(tt_common_entry,
					 head, hash_entry) {
			tt_local = container_of(tt_common_entry,
						struct batadv_tt_local_entry,
						common);
			vid = tt_common_entry->vid;
			last_seen_jiffies = jiffies - tt_local->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;

			no_purge = tt_common_entry->flags & np_flag;

			vlan = batadv_softif_vlan_get(bat_priv, vid);
			if (!vlan) {
				seq_printf(seq, "Cannot retrieve VLAN %d\n",
					   BATADV_PRINT_VID(vid));
				continue;
			}

			seq_printf(seq,
				   " * %pM %4i [%c%c%c%c%c%c] %3u.%03u   (%#.8x)\n",
				   tt_common_entry->addr,
				   BATADV_PRINT_VID(tt_common_entry->vid),
				   ((tt_common_entry->flags &
				     BATADV_TT_CLIENT_ROAM) ? 'R' : '.'),
				   no_purge ? 'P' : '.',
				   ((tt_common_entry->flags &
				     BATADV_TT_CLIENT_NEW) ? 'N' : '.'),
				   ((tt_common_entry->flags &
				     BATADV_TT_CLIENT_PENDING) ? 'X' : '.'),
				   ((tt_common_entry->flags &
				     BATADV_TT_CLIENT_WIFI) ? 'W' : '.'),
				   ((tt_common_entry->flags &
				     BATADV_TT_CLIENT_ISOLA) ? 'I' : '.'),
				   no_purge ? 0 : last_seen_secs,
				   no_purge ? 0 : last_seen_msecs,
				   vlan->tt.crc);

			batadv_softif_vlan_free_ref(vlan);
		}
		rcu_read_unlock();
	}
out:
	if (primary_if)
		batadv_hardif_free_ref(primary_if);
	return 0;
}

static void
batadv_tt_local_set_pending(struct batadv_priv *bat_priv,
			    struct batadv_tt_local_entry *tt_local_entry,
			    uint16_t flags, const char *message)
{
	batadv_tt_local_event(bat_priv, tt_local_entry, flags);

	/* The local client has to be marked as "pending to be removed" but has
	 * to be kept in the table in order to send it in a full table
	 * response issued before the net ttvn increment (consistency check)
	 */
	tt_local_entry->common.flags |= BATADV_TT_CLIENT_PENDING;

	batadv_dbg(BATADV_DBG_TT, bat_priv,
		   "Local tt entry (%pM, vid: %d) pending to be removed: %s\n",
		   tt_local_entry->common.addr,
		   BATADV_PRINT_VID(tt_local_entry->common.vid), message);
}

/**
 * batadv_tt_local_remove - logically remove an entry from the local table
 * @bat_priv: the bat priv with all the soft interface information
 * @addr: the MAC address of the client to remove
 * @vid: VLAN identifier
 * @message: message to append to the log on deletion
 * @roaming: true if the deletion is due to a roaming event
 *
 * Returns the flags assigned to the local entry before being deleted
 */
uint16_t batadv_tt_local_remove(struct batadv_priv *bat_priv,
				const uint8_t *addr, unsigned short vid,
				const char *message, bool roaming)
{
	struct batadv_tt_local_entry *tt_local_entry;
	uint16_t flags, curr_flags = BATADV_NO_FLAGS;
	struct batadv_softif_vlan *vlan;

	tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr, vid);
	if (!tt_local_entry)
		goto out;

	curr_flags = tt_local_entry->common.flags;

	flags = BATADV_TT_CLIENT_DEL;
	/* if this global entry addition is due to a roaming, the node has to
	 * mark the local entry as "roamed" in order to correctly reroute
	 * packets later
	 */
	if (roaming) {
		flags |= BATADV_TT_CLIENT_ROAM;
		/* mark the local client as ROAMed */
		tt_local_entry->common.flags |= BATADV_TT_CLIENT_ROAM;
	}

	if (!(tt_local_entry->common.flags & BATADV_TT_CLIENT_NEW)) {
		batadv_tt_local_set_pending(bat_priv, tt_local_entry, flags,
					    message);
		goto out;
	}
	/* if this client has been added right now, it is possible to
	 * immediately purge it
	 */
	batadv_tt_local_event(bat_priv, tt_local_entry, BATADV_TT_CLIENT_DEL);
	hlist_del_rcu(&tt_local_entry->common.hash_entry);
	batadv_tt_local_entry_free_ref(tt_local_entry);

	/* decrease the reference held for this vlan */
	vlan = batadv_softif_vlan_get(bat_priv, vid);
	batadv_softif_vlan_free_ref(vlan);
	batadv_softif_vlan_free_ref(vlan);

out:
	if (tt_local_entry)
		batadv_tt_local_entry_free_ref(tt_local_entry);

	return curr_flags;
}

/**
 * batadv_tt_local_purge_list - purge inactive tt local entries
 * @bat_priv: the bat priv with all the soft interface information
 * @head: pointer to the list containing the local tt entries
 * @timeout: parameter deciding whether a given tt local entry is considered
 *  inactive or not
 */
static void batadv_tt_local_purge_list(struct batadv_priv *bat_priv,
				       struct hlist_head *head,
				       int timeout)
{
	struct batadv_tt_local_entry *tt_local_entry;
	struct batadv_tt_common_entry *tt_common_entry;
	struct hlist_node *node_tmp;

	hlist_for_each_entry_safe(tt_common_entry, node_tmp, head,
				  hash_entry) {
		tt_local_entry = container_of(tt_common_entry,
					      struct batadv_tt_local_entry,
					      common);
		if (tt_local_entry->common.flags & BATADV_TT_CLIENT_NOPURGE)
			continue;

		/* entry already marked for deletion */
		if (tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING)
			continue;

		if (!batadv_has_timed_out(tt_local_entry->last_seen, timeout))
			continue;

		batadv_tt_local_set_pending(bat_priv, tt_local_entry,
					    BATADV_TT_CLIENT_DEL, "timed out");
	}
}

/**
 * batadv_tt_local_purge - purge inactive tt local entries
 * @bat_priv: the bat priv with all the soft interface information
 * @timeout: parameter deciding whether a given tt local entry is considered
 *  inactive or not
 */
static void batadv_tt_local_purge(struct batadv_priv *bat_priv,
				  int timeout)
{
	struct batadv_hashtable *hash = bat_priv->tt.local_hash;
	struct hlist_head *head;
	spinlock_t *list_lock; /* protects write access to the hash lists */
	uint32_t i;

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

		spin_lock_bh(list_lock);
		batadv_tt_local_purge_list(bat_priv, head, timeout);
		spin_unlock_bh(list_lock);
	}
}

static void batadv_tt_local_table_free(struct batadv_priv *bat_priv)
{
	struct batadv_hashtable *hash;
	spinlock_t *list_lock; /* protects write access to the hash lists */
	struct batadv_tt_common_entry *tt_common_entry;
	struct batadv_tt_local_entry *tt_local;
	struct batadv_softif_vlan *vlan;
	struct hlist_node *node_tmp;
	struct hlist_head *head;
	uint32_t i;

	if (!bat_priv->tt.local_hash)
		return;

	hash = bat_priv->tt.local_hash;

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

		spin_lock_bh(list_lock);
		hlist_for_each_entry_safe(tt_common_entry, node_tmp,
					  head, hash_entry) {
			hlist_del_rcu(&tt_common_entry->hash_entry);
			tt_local = container_of(tt_common_entry,
						struct batadv_tt_local_entry,
						common);

			/* decrease the reference held for this vlan */
			vlan = batadv_softif_vlan_get(bat_priv,
						      tt_common_entry->vid);
			batadv_softif_vlan_free_ref(vlan);
			batadv_softif_vlan_free_ref(vlan);

			batadv_tt_local_entry_free_ref(tt_local);
		}
		spin_unlock_bh(list_lock);
	}

	batadv_hash_destroy(hash);

	bat_priv->tt.local_hash = NULL;
}

static int batadv_tt_global_init(struct batadv_priv *bat_priv)
{
	if (bat_priv->tt.global_hash)
		return 0;

	bat_priv->tt.global_hash = batadv_hash_new(1024);

	if (!bat_priv->tt.global_hash)
		return -ENOMEM;

	batadv_hash_set_lock_class(bat_priv->tt.global_hash,
				   &batadv_tt_global_hash_lock_class_key);

	return 0;
}

static void batadv_tt_changes_list_free(struct batadv_priv *bat_priv)
{
	struct batadv_tt_change_node *entry, *safe;

	spin_lock_bh(&bat_priv->tt.changes_list_lock);

	list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
				 list) {
		list_del(&entry->list);
		kfree(entry);
	}

	atomic_set(&bat_priv->tt.local_changes, 0);
	spin_unlock_bh(&bat_priv->tt.changes_list_lock);
}

/* retrieves the orig_tt_list_entry belonging to orig_node from the
 * batadv_tt_global_entry list
 *
 * returns it with an increased refcounter, NULL if not found
 */
static struct batadv_tt_orig_list_entry *
batadv_tt_global_orig_entry_find(const struct batadv_tt_global_entry *entry,
				 const struct batadv_orig_node *orig_node)
{
	struct batadv_tt_orig_list_entry *tmp_orig_entry, *orig_entry = NULL;
	const struct hlist_head *head;

	rcu_read_lock();
	head = &entry->orig_list;
	hlist_for_each_entry_rcu(tmp_orig_entry, head, list) {
		if (tmp_orig_entry->orig_node != orig_node)
			continue;
		if (!atomic_inc_not_zero(&tmp_orig_entry->refcount))
			continue;

		orig_entry = tmp_orig_entry;
		break;
	}
	rcu_read_unlock();

	return orig_entry;
}

/* find out if an orig_node is already in the list of a tt_global_entry.
 * returns true if found, false otherwise
 */
static bool
batadv_tt_global_entry_has_orig(const struct batadv_tt_global_entry *entry,
				const struct batadv_orig_node *orig_node)
{
	struct batadv_tt_orig_list_entry *orig_entry;
	bool found = false;

	orig_entry = batadv_tt_global_orig_entry_find(entry, orig_node);
	if (orig_entry) {
		found = true;
		batadv_tt_orig_list_entry_free_ref(orig_entry);
	}

	return found;
}

static void
batadv_tt_global_orig_entry_add(struct batadv_tt_global_entry *tt_global,
				struct batadv_orig_node *orig_node, int ttvn)
{
	struct batadv_tt_orig_list_entry *orig_entry;

	orig_entry = batadv_tt_global_orig_entry_find(tt_global, orig_node);
	if (orig_entry) {
		/* refresh the ttvn: the current value could be a bogus one that
		 * was added during a "temporary client detection"
		 */
		orig_entry->ttvn = ttvn;
		goto out;
	}

	orig_entry = kzalloc(sizeof(*orig_entry), GFP_ATOMIC);
	if (!orig_entry)
		goto out;

	INIT_HLIST_NODE(&orig_entry->list);
	atomic_inc(&orig_node->refcount);
	batadv_tt_global_size_inc(orig_node, tt_global->common.vid);
	orig_entry->orig_node = orig_node;
	orig_entry->ttvn = ttvn;
	atomic_set(&orig_entry->refcount, 2);

	spin_lock_bh(&tt_global->list_lock);
	hlist_add_head_rcu(&orig_entry->list,
			   &tt_global->orig_list);
	spin_unlock_bh(&tt_global->list_lock);
	atomic_inc(&tt_global->orig_list_count);

out:
	if (orig_entry)
		batadv_tt_orig_list_entry_free_ref(orig_entry);
}

/**
 * batadv_tt_global_add - add a new TT global entry or update an existing one
 * @bat_priv: the bat priv with all the soft interface information
 * @orig_node: the originator announcing the client
 * @tt_addr: the mac address of the non-mesh client
 * @vid: VLAN identifier
 * @flags: TT flags that have to be set for this non-mesh client
 * @ttvn: the tt version number ever announcing this non-mesh client
 *
 * Add a new TT global entry for the given originator. If the entry already
 * exists add a new reference to the given originator (a global entry can have
 * references to multiple originators) and adjust the flags attribute to reflect
 * the function argument.
 * If a TT local entry exists for this non-mesh client remove it.
 *
 * The caller must hold orig_node refcount.
 *
 * Return true if the new entry has been added, false otherwise
 */
static bool batadv_tt_global_add(struct batadv_priv *bat_priv,
				 struct batadv_orig_node *orig_node,
				 const unsigned char *tt_addr,
				 unsigned short vid, uint16_t flags,
				 uint8_t ttvn)
{
	struct batadv_tt_global_entry *tt_global_entry;
	struct batadv_tt_local_entry *tt_local_entry;
	bool ret = false;
	int hash_added;
	struct batadv_tt_common_entry *common;
	uint16_t local_flags;

	/* ignore global entries from backbone nodes */
	if (batadv_bla_is_backbone_gw_orig(bat_priv, orig_node->orig, vid))
		return true;

	tt_global_entry = batadv_tt_global_hash_find(bat_priv, tt_addr, vid);
	tt_local_entry = batadv_tt_local_hash_find(bat_priv, tt_addr, vid);

	/* if the node already has a local client for this entry, it has to wait
	 * for a roaming advertisement instead of manually messing up the global
	 * table
	 */
	if ((flags & BATADV_TT_CLIENT_TEMP) && tt_local_entry &&
	    !(tt_local_entry->common.flags & BATADV_TT_CLIENT_NEW))
		goto out;

	if (!tt_global_entry) {
		tt_global_entry = kzalloc(sizeof(*tt_global_entry), GFP_ATOMIC);
		if (!tt_global_entry)
			goto out;

		common = &tt_global_entry->common;
		ether_addr_copy(common->addr, tt_addr);
		common->vid = vid;

		common->flags = flags;
		tt_global_entry->roam_at = 0;
		/* node must store current time in case of roaming. This is
		 * needed to purge this entry out on timeout (if nobody claims
		 * it)
		 */
		if (flags & BATADV_TT_CLIENT_ROAM)
			tt_global_entry->roam_at = jiffies;
		atomic_set(&common->refcount, 2);
		common->added_at = jiffies;

		INIT_HLIST_HEAD(&tt_global_entry->orig_list);
		atomic_set(&tt_global_entry->orig_list_count, 0);
		spin_lock_init(&tt_global_entry->list_lock);

		hash_added = batadv_hash_add(bat_priv->tt.global_hash,
					     batadv_compare_tt,
					     batadv_choose_tt, common,
					     &common->hash_entry);

		if (unlikely(hash_added != 0)) {
			/* remove the reference for the hash */
			batadv_tt_global_entry_free_ref(tt_global_entry);
			goto out_remove;
		}
	} else {
		common = &tt_global_entry->common;
		/* If there is already a global entry, we can use this one for
		 * our processing.
		 * But if we are trying to add a temporary client then here are
		 * two options at this point:
		 * 1) the global client is not a temporary client: the global
		 *    client has to be left as it is, temporary information
		 *    should never override any already known client state
		 * 2) the global client is a temporary client: purge the
		 *    originator list and add the new one orig_entry
		 */
		if (flags & BATADV_TT_CLIENT_TEMP) {
			if (!(common->flags & BATADV_TT_CLIENT_TEMP))
				goto out;
			if (batadv_tt_global_entry_has_orig(tt_global_entry,
							    orig_node))
				goto out_remove;
			batadv_tt_global_del_orig_list(tt_global_entry);
			goto add_orig_entry;
		}

		/* if the client was temporary added before receiving the first
		 * OGM announcing it, we have to clear the TEMP flag
		 */
		common->flags &= ~BATADV_TT_CLIENT_TEMP;

		/* the change can carry possible "attribute" flags like the
		 * TT_CLIENT_WIFI, therefore they have to be copied in the
		 * client entry
		 */
		tt_global_entry->common.flags |= flags;

		/* If there is the BATADV_TT_CLIENT_ROAM flag set, there is only
		 * one originator left in the list and we previously received a
		 * delete + roaming change for this originator.
		 *
		 * We should first delete the old originator before adding the
		 * new one.
		 */
		if (common->flags & BATADV_TT_CLIENT_ROAM) {
			batadv_tt_global_del_orig_list(tt_global_entry);
			common->flags &= ~BATADV_TT_CLIENT_ROAM;
			tt_global_entry->roam_at = 0;
		}
	}
add_orig_entry:
	/* add the new orig_entry (if needed) or update it */
	batadv_tt_global_orig_entry_add(tt_global_entry, orig_node, ttvn);

	batadv_dbg(BATADV_DBG_TT, bat_priv,
		   "Creating new global tt entry: %pM (vid: %d, via %pM)\n",
		   common->addr, BATADV_PRINT_VID(common->vid),
		   orig_node->orig);
	ret = true;

out_remove:
	/* Do not remove multicast addresses from the local hash on
	 * global additions
	 */
	if (is_multicast_ether_addr(tt_addr))
		goto out;

	/* remove address from local hash if present */
	local_flags = batadv_tt_local_remove(bat_priv, tt_addr, vid,
					     "global tt received",
					     flags & BATADV_TT_CLIENT_ROAM);
	tt_global_entry->common.flags |= local_flags & BATADV_TT_CLIENT_WIFI;

	if (!(flags & BATADV_TT_CLIENT_ROAM))
		/* this is a normal global add. Therefore the client is not in a
		 * roaming state anymore.
		 */
		tt_global_entry->common.flags &= ~BATADV_TT_CLIENT_ROAM;

out:
	if (tt_global_entry)
		batadv_tt_global_entry_free_ref(tt_global_entry);
	if (tt_local_entry)
		batadv_tt_local_entry_free_ref(tt_local_entry);
	return ret;
}

/**
 * batadv_transtable_best_orig - Get best originator list entry from tt entry
 * @bat_priv: the bat priv with all the soft interface information
 * @tt_global_entry: global translation table entry to be analyzed
 *
 * This functon assumes the caller holds rcu_read_lock().
 * Returns best originator list entry or NULL on errors.
 */
static struct batadv_tt_orig_list_entry *
batadv_transtable_best_orig(struct batadv_priv *bat_priv,
			    struct batadv_tt_global_entry *tt_global_entry)
{
	struct batadv_neigh_node *router, *best_router = NULL;
	struct batadv_algo_ops *bao = bat_priv->bat_algo_ops;
	struct hlist_head *head;
	struct batadv_tt_orig_list_entry *orig_entry, *best_entry = NULL;

	head = &tt_global_entry->orig_list;
	hlist_for_each_entry_rcu(orig_entry, head, list) {
		router = batadv_orig_router_get(orig_entry->orig_node,
						BATADV_IF_DEFAULT);
		if (!router)
			continue;

		if (best_router &&
		    bao->bat_neigh_cmp(router, BATADV_IF_DEFAULT,
				       best_router, BATADV_IF_DEFAULT) <= 0) {
			batadv_neigh_node_free_ref(router);
			continue;
		}

		/* release the refcount for the "old" best */
		if (best_router)
			batadv_neigh_node_free_ref(best_router);

		best_entry = orig_entry;
		best_router = router;
	}

	if (best_router)
		batadv_neigh_node_free_ref(best_router);

	return best_entry;
}

/**
 * batadv_tt_global_print_entry - print all orig nodes who announce the address
 *  for this global entry
 * @bat_priv: the bat priv with all the soft interface information
 * @tt_global_entry: global translation table entry to be printed
 * @seq: debugfs table seq_file struct
 *
 * This functon assumes the caller holds rcu_read_lock().
 */
static void
batadv_tt_global_print_entry(struct batadv_priv *bat_priv,
			     struct batadv_tt_global_entry *tt_global_entry,
			     struct seq_file *seq)
{
	struct batadv_tt_orig_list_entry *orig_entry, *best_entry;
	struct batadv_tt_common_entry *tt_common_entry;
	struct batadv_orig_node_vlan *vlan;
	struct hlist_head *head;
	uint8_t last_ttvn;
	uint16_t flags;

	tt_common_entry = &tt_global_entry->common;
	flags = tt_common_entry->flags;

	best_entry = batadv_transtable_best_orig(bat_priv, tt_global_entry);
	if (best_entry) {
		vlan = batadv_orig_node_vlan_get(best_entry->orig_node,
						 tt_common_entry->vid);
		if (!vlan) {
			seq_printf(seq,
				   " * Cannot retrieve VLAN %d for originator %pM\n",
				   BATADV_PRINT_VID(tt_common_entry->vid),
				   best_entry->orig_node->orig);
			goto print_list;
		}

		last_ttvn = atomic_read(&best_entry->orig_node->last_ttvn);
		seq_printf(seq,
			   " %c %pM %4i   (%3u) via %pM     (%3u)   (%#.8x) [%c%c%c%c]\n",
			   '*', tt_global_entry->common.addr,
			   BATADV_PRINT_VID(tt_global_entry->common.vid),
			   best_entry->ttvn, best_entry->orig_node->orig,
			   last_ttvn, vlan->tt.crc,
			   ((flags & BATADV_TT_CLIENT_ROAM) ? 'R' : '.'),
			   ((flags & BATADV_TT_CLIENT_WIFI) ? 'W' : '.'),
			   ((flags & BATADV_TT_CLIENT_ISOLA) ? 'I' : '.'),
			   ((flags & BATADV_TT_CLIENT_TEMP) ? 'T' : '.'));

		batadv_orig_node_vlan_free_ref(vlan);
	}

print_list:
	head = &tt_global_entry->orig_list;

	hlist_for_each_entry_rcu(orig_entry, head, list) {
		if (best_entry == orig_entry)
			continue;

		vlan = batadv_orig_node_vlan_get(orig_entry->orig_node,
						 tt_common_entry->vid);
		if (!vlan) {
			seq_printf(seq,
				   " + Cannot retrieve VLAN %d for originator %pM\n",
				   BATADV_PRINT_VID(tt_common_entry->vid),
				   orig_entry->orig_node->orig);
			continue;
		}

		last_ttvn = atomic_read(&orig_entry->orig_node->last_ttvn);
		seq_printf(seq,
			   " %c %pM %4d   (%3u) via %pM     (%3u)   (%#.8x) [%c%c%c%c]\n",
			   '+', tt_global_entry->common.addr,
			   BATADV_PRINT_VID(tt_global_entry->common.vid),
			   orig_entry->ttvn, orig_entry->orig_node->orig,
			   last_ttvn, vlan->tt.crc,
			   ((flags & BATADV_TT_CLIENT_ROAM) ? 'R' : '.'),
			   ((flags & BATADV_TT_CLIENT_WIFI) ? 'W' : '.'),
			   ((flags & BATADV_TT_CLIENT_ISOLA) ? 'I' : '.'),
			   ((flags & BATADV_TT_CLIENT_TEMP) ? 'T' : '.'));

		batadv_orig_node_vlan_free_ref(vlan);
	}
}

int batadv_tt_global_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_hashtable *hash = bat_priv->tt.global_hash;
	struct batadv_tt_common_entry *tt_common_entry;
	struct batadv_tt_global_entry *tt_global;
	struct batadv_hard_iface *primary_if;
	struct hlist_head *head;
	uint32_t i;

	primary_if = batadv_seq_print_text_primary_if_get(seq);
	if (!primary_if)
		goto out;

	seq_printf(seq,
		   "Globally announced TT entries received via the mesh %s\n",
		   net_dev->name);
	seq_printf(seq, "       %-13s  %s  %s       %-15s %s (%-10s) %s\n",
		   "Client", "VID", "(TTVN)", "Originator", "(Curr TTVN)",
		   "CRC", "Flags");

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

		rcu_read_lock();
		hlist_for_each_entry_rcu(tt_common_entry,
					 head, hash_entry) {
			tt_global = container_of(tt_common_entry,
						 struct batadv_tt_global_entry,
						 common);
			batadv_tt_global_print_entry(bat_priv, tt_global, seq);
		}
		rcu_read_unlock();
	}
out:
	if (primary_if)
		batadv_hardif_free_ref(primary_if);
	return 0;
}

/**
 * batadv_tt_global_del_orig_entry - remove and free an orig_entry
 * @tt_global_entry: the global entry to remove the orig_entry from
 * @orig_entry: the orig entry to remove and free
 *
 * Remove an orig_entry from its list in the given tt_global_entry and
 * free this orig_entry afterwards.
 */
static void
batadv_tt_global_del_orig_entry(struct batadv_tt_global_entry *tt_global_entry,
				struct batadv_tt_orig_list_entry *orig_entry)
{
	batadv_tt_global_size_dec(orig_entry->orig_node,
				  tt_global_entry->common.vid);
	atomic_dec(&tt_global_entry->orig_list_count);
	hlist_del_rcu(&orig_entry->list);
	batadv_tt_orig_list_entry_free_ref(orig_entry);
}

/* deletes the orig list of a tt_global_entry */
static void
batadv_tt_global_del_orig_list(struct batadv_tt_global_entry *tt_global_entry)
{
	struct hlist_head *head;
	struct hlist_node *safe;
	struct batadv_tt_orig_list_entry *orig_entry;

	spin_lock_bh(&tt_global_entry->list_lock);
	head = &tt_global_entry->orig_list;
	hlist_for_each_entry_safe(orig_entry, safe, head, list)
		batadv_tt_global_del_orig_entry(tt_global_entry, orig_entry);
	spin_unlock_bh(&tt_global_entry->list_lock);
}

/**
 * batadv_tt_global_del_orig_node - remove orig_node from a global tt entry
 * @bat_priv: the bat priv with all the soft interface information
 * @tt_global_entry: the global entry to remove the orig_node from
 * @orig_node: the originator announcing the client
 * @message: message to append to the log on deletion
 *
 * Remove the given orig_node and its according orig_entry from the given
 * global tt entry.
 */
static void
batadv_tt_global_del_orig_node(struct batadv_priv *bat_priv,
			       struct batadv_tt_global_entry *tt_global_entry,
			       struct batadv_orig_node *orig_node,
			       const char *message)
{
	struct hlist_head *head;
	struct hlist_node *safe;
	struct batadv_tt_orig_list_entry *orig_entry;
	unsigned short vid;

	spin_lock_bh(&tt_global_entry->list_lock);
	head = &tt_global_entry->orig_list;
	hlist_for_each_entry_safe(orig_entry, safe, head, list) {
		if (orig_entry->orig_node == orig_node) {
			vid = tt_global_entry->common.vid;
			batadv_dbg(BATADV_DBG_TT, bat_priv,
				   "Deleting %pM from global tt entry %pM (vid: %d): %s\n",
				   orig_node->orig,
				   tt_global_entry->common.addr,
				   BATADV_PRINT_VID(vid), message);
			batadv_tt_global_del_orig_entry(tt_global_entry,
							orig_entry);
		}
	}
	spin_unlock_bh(&tt_global_entry->list_lock);
}

/* If the client is to be deleted, we check if it is the last origantor entry
 * within tt_global entry. If yes, we set the BATADV_TT_CLIENT_ROAM flag and the
 * timer, otherwise we simply remove the originator scheduled for deletion.
 */
static void
batadv_tt_global_del_roaming(struct batadv_priv *bat_priv,
			     struct batadv_tt_global_entry *tt_global_entry,
			     struct batadv_orig_node *orig_node,
			     const char *message)
{
	bool last_entry = true;
	struct hlist_head *head;
	struct batadv_tt_orig_list_entry *orig_entry;

	/* no local entry exists, case 1:
	 * Check if this is the last one or if other entries exist.
	 */

	rcu_read_lock();
	head = &tt_global_entry->orig_list;
	hlist_for_each_entry_rcu(orig_entry, head, list) {
		if (orig_entry->orig_node != orig_node) {
			last_entry = false;
			break;
		}
	}
	rcu_read_unlock();

	if (last_entry) {
		/* its the last one, mark for roaming. */
		tt_global_entry->common.flags |= BATADV_TT_CLIENT_ROAM;
		tt_global_entry->roam_at = jiffies;
	} else
		/* there is another entry, we can simply delete this
		 * one and can still use the other one.
		 */
		batadv_tt_global_del_orig_node(bat_priv, tt_global_entry,
					       orig_node, message);
}

/**
 * batadv_tt_global_del - remove a client from the global table
 * @bat_priv: the bat priv with all the soft interface information
 * @orig_node: an originator serving this client
 * @addr: the mac address of the client
 * @vid: VLAN identifier
 * @message: a message explaining the reason for deleting the client to print
 *  for debugging purpose
 * @roaming: true if the deletion has been triggered by a roaming event
 */
static void batadv_tt_global_del(struct batadv_priv *bat_priv,
				 struct batadv_orig_node *orig_node,
				 const unsigned char *addr, unsigned short vid,
				 const char *message, bool roaming)
{
	struct batadv_tt_global_entry *tt_global_entry;
	struct batadv_tt_local_entry *local_entry = NULL;

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

	if (!roaming) {
		batadv_tt_global_del_orig_node(bat_priv, tt_global_entry,
					       orig_node, message);

		if (hlist_empty(&tt_global_entry->orig_list))
			batadv_tt_global_free(bat_priv, tt_global_entry,
					      message);

		goto out;
	}

	/* if we are deleting a global entry due to a roam
	 * event, there are two possibilities:
	 * 1) the client roamed from node A to node B => if there
	 *    is only one originator left for this client, we mark
	 *    it with BATADV_TT_CLIENT_ROAM, we start a timer and we
	 *    wait for node B to claim it. In case of timeout
	 *    the entry is purged.
	 *
	 *    If there are other originators left, we directly delete
	 *    the originator.
	 * 2) the client roamed to us => we can directly delete
	 *    the global entry, since it is useless now.
	 */
	local_entry = batadv_tt_local_hash_find(bat_priv,
						tt_global_entry->common.addr,
						vid);
	if (local_entry) {
		/* local entry exists, case 2: client roamed to us. */
		batadv_tt_global_del_orig_list(tt_global_entry);
		batadv_tt_global_free(bat_priv, tt_global_entry, message);
	} else
		/* no local entry exists, case 1: check for roaming */
		batadv_tt_global_del_roaming(bat_priv, tt_global_entry,
					     orig_node, message);

out:
	if (tt_global_entry)
		batadv_tt_global_entry_free_ref(tt_global_entry);
	if (local_entry)
		batadv_tt_local_entry_free_ref(local_entry);
}

/**
 * batadv_tt_global_del_orig - remove all the TT global entries belonging to the
 *  given originator matching the provided vid
 * @bat_priv: the bat priv with all the soft interface information
 * @orig_node: the originator owning the entries to remove
 * @match_vid: the VLAN identifier to match. If negative all the entries will be
 *  removed
 * @message: debug message to print as "reason"
 */
void batadv_tt_global_del_orig(struct batadv_priv *bat_priv,
			       struct batadv_orig_node *orig_node,
			       int32_t match_vid,
			       const char *message)
{
	struct batadv_tt_global_entry *tt_global;
	struct batadv_tt_common_entry *tt_common_entry;
	uint32_t i;
	struct batadv_hashtable *hash = bat_priv->tt.global_hash;
	struct hlist_node *safe;
	struct hlist_head *head;
	spinlock_t *list_lock; /* protects write access to the hash lists */
	unsigned short vid;

	if (!hash)
		return;

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

		spin_lock_bh(list_lock);
		hlist_for_each_entry_safe(tt_common_entry, safe,
					  head, hash_entry) {
			/* remove only matching entries */
			if (match_vid >= 0 && tt_common_entry->vid != match_vid)
				continue;

			tt_global = container_of(tt_common_entry,
						 struct batadv_tt_global_entry,
						 common);

			batadv_tt_global_del_orig_node(bat_priv, tt_global,
						       orig_node, message);

			if (hlist_empty(&tt_global->orig_list)) {
				vid = tt_global->common.vid;
				batadv_dbg(BATADV_DBG_TT, bat_priv,
					   "Deleting global tt entry %pM (vid: %d): %s\n",
					   tt_global->common.addr,
					   BATADV_PRINT_VID(vid), message);
				hlist_del_rcu(&tt_common_entry->hash_entry);
				batadv_tt_global_entry_free_ref(tt_global);
			}
		}
		spin_unlock_bh(list_lock);
	}
	orig_node->capa_initialized &= ~BATADV_ORIG_CAPA_HAS_TT;
}

static bool batadv_tt_global_to_purge(struct batadv_tt_global_entry *tt_global,
				      char **msg)
{
	bool purge = false;
	unsigned long roam_timeout = BATADV_TT_CLIENT_ROAM_TIMEOUT;
	unsigned long temp_timeout = BATADV_TT_CLIENT_TEMP_TIMEOUT;

	if ((tt_global->common.flags & BATADV_TT_CLIENT_ROAM) &&
	    batadv_has_timed_out(tt_global->roam_at, roam_timeout)) {
		purge = true;
		*msg = "Roaming timeout\n";
	}

	if ((tt_global->common.flags & BATADV_TT_CLIENT_TEMP) &&
	    batadv_has_timed_out(tt_global->common.added_at, temp_timeout)) {
		purge = true;
		*msg = "Temporary client timeout\n";
	}

	return purge;
}

static void batadv_tt_global_purge(struct batadv_priv *bat_priv)
{
	struct batadv_hashtable *hash = bat_priv->tt.global_hash;
	struct hlist_head *head;
	struct hlist_node *node_tmp;
	spinlock_t *list_lock; /* protects write access to the hash lists */
	uint32_t i;
	char *msg = NULL;
	struct batadv_tt_common_entry *tt_common;
	struct batadv_tt_global_entry *tt_global;

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

		spin_lock_bh(list_lock);
		hlist_for_each_entry_safe(tt_common, node_tmp, head,
					  hash_entry) {
			tt_global = container_of(tt_common,
						 struct batadv_tt_global_entry,
						 common);

			if (!batadv_tt_global_to_purge(tt_global, &msg))
				continue;

			batadv_dbg(BATADV_DBG_TT, bat_priv,
				   "Deleting global tt entry %pM (vid: %d): %s\n",
				   tt_global->common.addr,
				   BATADV_PRINT_VID(tt_global->common.vid),
				   msg);

			hlist_del_rcu(&tt_common->hash_entry);

			batadv_tt_global_entry_free_ref(tt_global);
		}
		spin_unlock_bh(list_lock);
	}
}

static void batadv_tt_global_table_free(struct batadv_priv *bat_priv)
{
	struct batadv_hashtable *hash;
	spinlock_t *list_lock; /* protects write access to the hash lists */
	struct batadv_tt_common_entry *tt_common_entry;
	struct batadv_tt_global_entry *tt_global;
	struct hlist_node *node_tmp;
	struct hlist_head *head;
	uint32_t i;

	if (!bat_priv->tt.global_hash)
		return;

	hash = bat_priv->tt.global_hash;

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

		spin_lock_bh(list_lock);
		hlist_for_each_entry_safe(tt_common_entry, node_tmp,
					  head, hash_entry) {
			hlist_del_rcu(&tt_common_entry->hash_entry);
			tt_global = container_of(tt_common_entry,
						 struct batadv_tt_global_entry,
						 common);
			batadv_tt_global_entry_free_ref(tt_global);
		}
		spin_unlock_bh(list_lock);
	}

	batadv_hash_destroy(hash);

	bat_priv->tt.global_hash = NULL;
}

static bool
_batadv_is_ap_isolated(struct batadv_tt_local_entry *tt_local_entry,
		       struct batadv_tt_global_entry *tt_global_entry)
{
	bool ret = false;

	if (tt_local_entry->common.flags & BATADV_TT_CLIENT_WIFI &&
	    tt_global_entry->common.flags & BATADV_TT_CLIENT_WIFI)
		ret = true;

	/* check if the two clients are marked as isolated */
	if (tt_local_entry->common.flags & BATADV_TT_CLIENT_ISOLA &&
	    tt_global_entry->common.flags & BATADV_TT_CLIENT_ISOLA)
		ret = true;

	return ret;
}

/**
 * batadv_transtable_search - get the mesh destination for a given client
 * @bat_priv: the bat priv with all the soft interface information
 * @src: mac address of the source client
 * @addr: mac address of the destination client
 * @vid: VLAN identifier
 *
 * Returns a pointer to the originator that was selected as destination in the
 * mesh for contacting the client 'addr', NULL otherwise.
 * In case of multiple originators serving the same client, the function returns
 * the best one (best in terms of metric towards the destination node).
 *
 * If the two clients are AP isolated the function returns NULL.
 */
struct batadv_orig_node *batadv_transtable_search(struct batadv_priv *bat_priv,
						  const uint8_t *src,
						  const uint8_t *addr,
						  unsigned short vid)
{
	struct batadv_tt_local_entry *tt_local_entry = NULL;
	struct batadv_tt_global_entry *tt_global_entry = NULL;
	struct batadv_orig_node *orig_node = NULL;
	struct batadv_tt_orig_list_entry *best_entry;

	if (src && batadv_vlan_ap_isola_get(bat_priv, vid)) {
		tt_local_entry = batadv_tt_local_hash_find(bat_priv, src, vid);
		if (!tt_local_entry ||
		    (tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING))
			goto out;
	}

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

	/* check whether the clients should not communicate due to AP
	 * isolation
	 */
	if (tt_local_entry &&
	    _batadv_is_ap_isolated(tt_local_entry, tt_global_entry))
		goto out;

	rcu_read_lock();
	best_entry = batadv_transtable_best_orig(bat_priv, tt_global_entry);
	/* found anything? */
	if (best_entry)
		orig_node = best_entry->orig_node;
	if (orig_node && !atomic_inc_not_zero(&orig_node->refcount))
		orig_node = NULL;
	rcu_read_unlock();

out:
	if (tt_global_entry)
		batadv_tt_global_entry_free_ref(tt_global_entry);
	if (tt_local_entry)
		batadv_tt_local_entry_free_ref(tt_local_entry);

	return orig_node;
}

/**
 * batadv_tt_global_crc - calculates the checksum of the local table belonging
 *  to the given orig_node
 * @bat_priv: the bat priv with all the soft interface information
 * @orig_node: originator for which the CRC should be computed
 * @vid: VLAN identifier for which the CRC32 has to be computed
 *
 * This function computes the checksum for the global table corresponding to a
 * specific originator. In particular, the checksum is computed as follows: For
 * each client connected to the originator the CRC32C of the MAC address and the
 * VID is computed and then all the CRC32Cs of the various clients are xor'ed
 * together.
 *
 * The idea behind is that CRC32C should be used as much as possible in order to
 * produce a unique hash of the table, but since the order which is used to feed
 * the CRC32C function affects the result and since every node in the network
 * probably sorts the clients differently, the hash function cannot be directly
 * computed over the entire table. Hence the CRC32C is used only on
 * the single client entry, while all the results are then xor'ed together
 * because the XOR operation can combine them all while trying to reduce the
 * noise as much as possible.
 *
 * Returns the checksum of the global table of a given originator.
 */
static uint32_t batadv_tt_global_crc(struct batadv_priv *bat_priv,
				     struct batadv_orig_node *orig_node,
				     unsigned short vid)
{
	struct batadv_hashtable *hash = bat_priv->tt.global_hash;
	struct batadv_tt_common_entry *tt_common;
	struct batadv_tt_global_entry *tt_global;
	struct hlist_head *head;
	uint32_t i, crc_tmp, crc = 0;
	uint8_t flags;
	__be16 tmp_vid;

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

		rcu_read_lock();
		hlist_for_each_entry_rcu(tt_common, head, hash_entry) {
			tt_global = container_of(tt_common,
						 struct batadv_tt_global_entry,
						 common);
			/* compute the CRC only for entries belonging to the
			 * VLAN identified by the vid passed as parameter
			 */
			if (tt_common->vid != vid)
				continue;

			/* Roaming clients are in the global table for
			 * consistency only. They don't have to be
			 * taken into account while computing the
			 * global crc
			 */
			if (tt_common->flags & BATADV_TT_CLIENT_ROAM)
				continue;
			/* Temporary clients have not been announced yet, so
			 * they have to be skipped while computing the global
			 * crc
			 */
			if (tt_common->flags & BATADV_TT_CLIENT_TEMP)
				continue;

			/* find out if this global entry is announced by this
			 * originator
			 */
			if (!batadv_tt_global_entry_has_orig(tt_global,
							     orig_node))
				continue;

			/* use network order to read the VID: this ensures that
			 * every node reads the bytes in the same order.
			 */
			tmp_vid = htons(tt_common->vid);
			crc_tmp = crc32c(0, &tmp_vid, sizeof(tmp_vid));

			/* compute the CRC on flags that have to be kept in sync
			 * among nodes
			 */
			flags = tt_common->flags & BATADV_TT_SYNC_MASK;
			crc_tmp = crc32c(crc_tmp, &flags, sizeof(flags));

			crc ^= crc32c(crc_tmp, tt_common->addr, ETH_ALEN);
		}
		rcu_read_unlock();
	}

	return crc;
}

/**
 * batadv_tt_local_crc - calculates the checksum of the local table
 * @bat_priv: the bat priv with all the soft interface information
 * @vid: VLAN identifier for which the CRC32 has to be computed
 *
 * For details about the computation, please refer to the documentation for
 * batadv_tt_global_crc().
 *
 * Returns the checksum of the local table
 */
static uint32_t batadv_tt_local_crc(struct batadv_priv *bat_priv,
				    unsigned short vid)
{
	struct batadv_hashtable *hash = bat_priv->tt.local_hash;
	struct batadv_tt_common_entry *tt_common;
	struct hlist_head *head;
	uint32_t i, crc_tmp, crc = 0;
	uint8_t flags;
	__be16 tmp_vid;

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

		rcu_read_lock();
		hlist_for_each_entry_rcu(tt_common, head, hash_entry) {
			/* compute the CRC only for entries belonging to the
			 * VLAN identified by vid
			 */
			if (tt_common->vid != vid)
				continue;

			/* not yet committed clients have not to be taken into
			 * account while computing the CRC
			 */
			if (tt_common->flags & BATADV_TT_CLIENT_NEW)
				continue;

			/* use network order to read the VID: this ensures that
			 * every node reads the bytes in the same order.
			 */
			tmp_vid = htons(tt_common->vid);
			crc_tmp = crc32c(0, &tmp_vid, sizeof(tmp_vid));

			/* compute the CRC on flags that have to be kept in sync
			 * among nodes
			 */
			flags = tt_common->flags & BATADV_TT_SYNC_MASK;
			crc_tmp = crc32c(crc_tmp, &flags, sizeof(flags));

			crc ^= crc32c(crc_tmp, tt_common->addr, ETH_ALEN);
		}
		rcu_read_unlock();
	}

	return crc;
}

static void batadv_tt_req_list_free(struct batadv_priv *bat_priv)
{
	struct batadv_tt_req_node *node, *safe;

	spin_lock_bh(&bat_priv->tt.req_list_lock);

	list_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
		list_del(&node->list);
		kfree(node);
	}

	spin_unlock_bh(&bat_priv->tt.req_list_lock);
}

static void batadv_tt_save_orig_buffer(struct batadv_priv *bat_priv,
				       struct batadv_orig_node *orig_node,
				       const void *tt_buff,
				       uint16_t tt_buff_len)
{
	/* Replace the old buffer only if I received something in the
	 * last OGM (the OGM could carry no changes)
	 */
	spin_lock_bh(&orig_node->tt_buff_lock);
	if (tt_buff_len > 0) {
		kfree(orig_node->tt_buff);
		orig_node->tt_buff_len = 0;
		orig_node->tt_buff = kmalloc(tt_buff_len, GFP_ATOMIC);
		if (orig_node->tt_buff) {
			memcpy(orig_node->tt_buff, tt_buff, tt_buff_len);
			orig_node->tt_buff_len = tt_buff_len;
		}
	}
	spin_unlock_bh(&orig_node->tt_buff_lock);
}

static void batadv_tt_req_purge(struct batadv_priv *bat_priv)
{
	struct batadv_tt_req_node *node, *safe;

	spin_lock_bh(&bat_priv->tt.req_list_lock);
	list_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
		if (batadv_has_timed_out(node->issued_at,
					 BATADV_TT_REQUEST_TIMEOUT)) {
			list_del(&node->list);
			kfree(node);
		}
	}
	spin_unlock_bh(&bat_priv->tt.req_list_lock);
}

/* returns the pointer to the new tt_req_node struct if no request
 * has already been issued for this orig_node, NULL otherwise
 */
static struct batadv_tt_req_node *
batadv_new_tt_req_node(struct batadv_priv *bat_priv,
		       struct batadv_orig_node *orig_node)
{
	struct batadv_tt_req_node *tt_req_node_tmp, *tt_req_node = NULL;

	spin_lock_bh(&bat_priv->tt.req_list_lock);
	list_for_each_entry(tt_req_node_tmp, &bat_priv->tt.req_list, list) {
		if (batadv_compare_eth(tt_req_node_tmp, orig_node) &&
		    !batadv_has_timed_out(tt_req_node_tmp->issued_at,
					  BATADV_TT_REQUEST_TIMEOUT))
			goto unlock;
	}

	tt_req_node = kmalloc(sizeof(*tt_req_node), GFP_ATOMIC);
	if (!tt_req_node)
		goto unlock;

	ether_addr_copy(tt_req_node->addr, orig_node->orig);
	tt_req_node->issued_at = jiffies;

	list_add(&tt_req_node->list, &bat_priv->tt.req_list);
unlock:
	spin_unlock_bh(&bat_priv->tt.req_list_lock);
	return tt_req_node;
}

/**
 * batadv_tt_local_valid - verify that given tt entry is a valid one
 * @entry_ptr: to be checked local tt entry
 * @data_ptr: not used but definition required to satisfy the callback prototype
 *
 * Returns 1 if the entry is a valid, 0 otherwise.
 */
static int batadv_tt_local_valid(const void *entry_ptr, const void *data_ptr)
{
	const struct batadv_tt_common_entry *tt_common_entry = entry_ptr;

	if (tt_common_entry->flags & BATADV_TT_CLIENT_NEW)
		return 0;
	return 1;
}

static int batadv_tt_global_valid(const void *entry_ptr,
				  const void *data_ptr)
{
	const struct batadv_tt_common_entry *tt_common_entry = entry_ptr;
	const struct batadv_tt_global_entry *tt_global_entry;
	const struct batadv_orig_node *orig_node = data_ptr;

	if (tt_common_entry->flags & BATADV_TT_CLIENT_ROAM ||
	    tt_common_entry->flags & BATADV_TT_CLIENT_TEMP)
		return 0;

	tt_global_entry = container_of(tt_common_entry,
				       struct batadv_tt_global_entry,
				       common);

	return batadv_tt_global_entry_has_orig(tt_global_entry, orig_node);
}

/**
 * batadv_tt_tvlv_generate - fill the tvlv buff with the tt entries from the
 *  specified tt hash
 * @bat_priv: the bat priv with all the soft interface information
 * @hash: hash table containing the tt entries
 * @tt_len: expected tvlv tt data buffer length in number of bytes
 * @tvlv_buff: pointer to the buffer to fill with the TT data
 * @valid_cb: function to filter tt change entries
 * @cb_data: data passed to the filter function as argument
 */
static void batadv_tt_tvlv_generate(struct batadv_priv *bat_priv,
				    struct batadv_hashtable *hash,
				    void *tvlv_buff, uint16_t tt_len,
				    int (*valid_cb)(const void *, const void *),
				    void *cb_data)
{
	struct batadv_tt_common_entry *tt_common_entry;
	struct batadv_tvlv_tt_change *tt_change;
	struct hlist_head *head;
	uint16_t tt_tot, tt_num_entries = 0;
	uint32_t i;

	tt_tot = batadv_tt_entries(tt_len);
	tt_change = (struct batadv_tvlv_tt_change *)tvlv_buff;

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

		hlist_for_each_entry_rcu(tt_common_entry,
					 head, hash_entry) {
			if (tt_tot == tt_num_entries)
				break;

			if ((valid_cb) && (!valid_cb(tt_common_entry, cb_data)))
				continue;

			ether_addr_copy(tt_change->addr, tt_common_entry->addr);
			tt_change->flags = tt_common_entry->flags;
			tt_change->vid = htons(tt_common_entry->vid);
			memset(tt_change->reserved, 0,
			       sizeof(tt_change->reserved));

			tt_num_entries++;
			tt_change++;
		}
	}
	rcu_read_unlock();
}

/**
 * batadv_tt_global_check_crc - check if all the CRCs are correct
 * @orig_node: originator for which the CRCs have to be checked
 * @tt_vlan: pointer to the first tvlv VLAN entry
 * @num_vlan: number of tvlv VLAN entries
 * @create: if true, create VLAN objects if not found
 *
 * Return true if all the received CRCs match the locally stored ones, false
 * otherwise
 */
static bool batadv_tt_global_check_crc(struct batadv_orig_node *orig_node,
				       struct batadv_tvlv_tt_vlan_data *tt_vlan,
				       uint16_t num_vlan)
{
	struct batadv_tvlv_tt_vlan_data *tt_vlan_tmp;
	struct batadv_orig_node_vlan *vlan;
	uint32_t crc;
	int i;

	/* check if each received CRC matches the locally stored one */
	for (i = 0; i < num_vlan; i++) {
		tt_vlan_tmp = tt_vlan + i;

		/* if orig_node is a backbone node for this VLAN, don't check
		 * the CRC as we ignore all the global entries over it
		 */
		if (batadv_bla_is_backbone_gw_orig(orig_node->bat_priv,
						   orig_node->orig,
						   ntohs(tt_vlan_tmp->vid)))
			continue;

		vlan = batadv_orig_node_vlan_get(orig_node,
						 ntohs(tt_vlan_tmp->vid));
		if (!vlan)
			return false;

		crc = vlan->tt.crc;
		batadv_orig_node_vlan_free_ref(vlan);

		if (crc != ntohl(tt_vlan_tmp->crc))
			return false;
	}

	return true;
}

/**
 * batadv_tt_local_update_crc - update all the local CRCs
 * @bat_priv: the bat priv with all the soft interface information
 */
static void batadv_tt_local_update_crc(struct batadv_priv *bat_priv)
{
	struct batadv_softif_vlan *vlan;

	/* recompute the global CRC for each VLAN */
	rcu_read_lock();
	hlist_for_each_entry_rcu(vlan, &bat_priv->softif_vlan_list, list) {
		vlan->tt.crc = batadv_tt_local_crc(bat_priv, vlan->vid);
	}
	rcu_read_unlock();
}

/**
 * batadv_tt_global_update_crc - update all the global CRCs for this orig_node
 * @bat_priv: the bat priv with all the soft interface information
 * @orig_node: the orig_node for which the CRCs have to be updated
 */
static void batadv_tt_global_update_crc(struct batadv_priv *bat_priv,
					struct batadv_orig_node *orig_node)
{
	struct batadv_orig_node_vlan *vlan;
	uint32_t crc;

	/* recompute the global CRC for each VLAN */
	rcu_read_lock();
	list_for_each_entry_rcu(vlan, &orig_node->vlan_list, list) {
		/* if orig_node is a backbone node for this VLAN, don't compute
		 * the CRC as we ignore all the global entries over it
		 */
		if (batadv_bla_is_backbone_gw_orig(bat_priv, orig_node->orig,
						   vlan->vid))
			continue;

		crc = batadv_tt_global_crc(bat_priv, orig_node, vlan->vid);
		vlan->tt.crc = crc;
	}
	rcu_read_unlock();
}

/**
 * batadv_send_tt_request - send a TT Request message to a given node
 * @bat_priv: the bat priv with all the soft interface information
 * @dst_orig_node: the destination of the message
 * @ttvn: the version number that the source of the message is looking for
 * @tt_vlan: pointer to the first tvlv VLAN object to request
 * @num_vlan: number of tvlv VLAN entries
 * @full_table: ask for the entire translation table if true, while only for the
 *  last TT diff otherwise
 */
static int batadv_send_tt_request(struct batadv_priv *bat_priv,
				  struct batadv_orig_node *dst_orig_node,
				  uint8_t ttvn,
				  struct batadv_tvlv_tt_vlan_data *tt_vlan,
				  uint16_t num_vlan, bool full_table)
{
	struct batadv_tvlv_tt_data *tvlv_tt_data = NULL;
	struct batadv_tt_req_node *tt_req_node = NULL;
	struct batadv_tvlv_tt_vlan_data *tt_vlan_req;
	struct batadv_hard_iface *primary_if;
	bool ret = false;
	int i, size;

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

	/* The new tt_req will be issued only if I'm not waiting for a
	 * reply from the same orig_node yet
	 */
	tt_req_node = batadv_new_tt_req_node(bat_priv, dst_orig_node);
	if (!tt_req_node)
		goto out;

	size = sizeof(*tvlv_tt_data) + sizeof(*tt_vlan_req) * num_vlan;
	tvlv_tt_data = kzalloc(size, GFP_ATOMIC);
	if (!tvlv_tt_data)
		goto out;

	tvlv_tt_data->flags = BATADV_TT_REQUEST;
	tvlv_tt_data->ttvn = ttvn;
	tvlv_tt_data->num_vlan = htons(num_vlan);

	/* send all the CRCs within the request. This is needed by intermediate
	 * nodes to ensure they have the correct table before replying
	 */
	tt_vlan_req = (struct batadv_tvlv_tt_vlan_data *)(tvlv_tt_data + 1);
	for (i = 0; i < num_vlan; i++) {
		tt_vlan_req->vid = tt_vlan->vid;
		tt_vlan_req->crc = tt_vlan->crc;

		tt_vlan_req++;
		tt_vlan++;
	}

	if (full_table)
		tvlv_tt_data->flags |= BATADV_TT_FULL_TABLE;

	batadv_dbg(BATADV_DBG_TT, bat_priv, "Sending TT_REQUEST to %pM [%c]\n",
		   dst_orig_node->orig, full_table ? 'F' : '.');

	batadv_inc_counter(bat_priv, BATADV_CNT_TT_REQUEST_TX);
	batadv_tvlv_unicast_send(bat_priv, primary_if->net_dev->dev_addr,
				 dst_orig_node->orig, BATADV_TVLV_TT, 1,
				 tvlv_tt_data, size);
	ret = true;

out:
	if (primary_if)
		batadv_hardif_free_ref(primary_if);
	if (ret && tt_req_node) {
		spin_lock_bh(&bat_priv->tt.req_list_lock);
		list_del(&tt_req_node->list);
		spin_unlock_bh(&bat_priv->tt.req_list_lock);
		kfree(tt_req_node);
	}
	kfree(tvlv_tt_data);
	return ret;
}

/**
 * batadv_send_other_tt_response - send reply to tt request concerning another
 *  node's translation table
 * @bat_priv: the bat priv with all the soft interface information
 * @tt_data: tt data containing the tt request information
 * @req_src: mac address of tt request sender
 * @req_dst: mac address of tt request recipient
 *
 * Returns true if tt request reply was sent, false otherwise.
 */
static bool batadv_send_other_tt_response(struct batadv_priv *bat_priv,
					  struct batadv_tvlv_tt_data *tt_data,
					  uint8_t *req_src, uint8_t *req_dst)
{
	struct batadv_orig_node *req_dst_orig_node;
	struct batadv_orig_node *res_dst_orig_node = NULL;
	struct batadv_tvlv_tt_change *tt_change;
	struct batadv_tvlv_tt_data *tvlv_tt_data = NULL;
	struct batadv_tvlv_tt_vlan_data *tt_vlan;
	bool ret = false, full_table;
	uint8_t orig_ttvn, req_ttvn;
	uint16_t tvlv_len;
	int32_t tt_len;

	batadv_dbg(BATADV_DBG_TT, bat_priv,
		   "Received TT_REQUEST from %pM for ttvn: %u (%pM) [%c]\n",
		   req_src, tt_data->ttvn, req_dst,
		   ((tt_data->flags & BATADV_TT_FULL_TABLE) ? 'F' : '.'));

	/* Let's get the orig node of the REAL destination */
	req_dst_orig_node = batadv_orig_hash_find(bat_priv, req_dst);
	if (!req_dst_orig_node)
		goto out;

	res_dst_orig_node = batadv_orig_hash_find(bat_priv, req_src);
	if (!res_dst_orig_node)
		goto out;

	orig_ttvn = (uint8_t)atomic_read(&req_dst_orig_node->last_ttvn);
	req_ttvn = tt_data->ttvn;

	tt_vlan = (struct batadv_tvlv_tt_vlan_data *)(tt_data + 1);
	/* this node doesn't have the requested data */
	if (orig_ttvn != req_ttvn ||
	    !batadv_tt_global_check_crc(req_dst_orig_node, tt_vlan,
					ntohs(tt_data->num_vlan)))
		goto out;

	/* If the full table has been explicitly requested */
	if (tt_data->flags & BATADV_TT_FULL_TABLE ||
	    !req_dst_orig_node->tt_buff)
		full_table = true;
	else
		full_table = false;

	/* TT fragmentation hasn't been implemented yet, so send as many
	 * TT entries fit a single packet as possible only
	 */
	if (!full_table) {
		spin_lock_bh(&req_dst_orig_node->tt_buff_lock);
		tt_len = req_dst_orig_node->tt_buff_len;

		tvlv_len = batadv_tt_prepare_tvlv_global_data(req_dst_orig_node,
							      &tvlv_tt_data,
							      &tt_change,
							      &tt_len);
		if (!tt_len)
			goto unlock;

		/* Copy the last orig_node's OGM buffer */
		memcpy(tt_change, req_dst_orig_node->tt_buff,
		       req_dst_orig_node->tt_buff_len);
		spin_unlock_bh(&req_dst_orig_node->tt_buff_lock);
	} else {
		/* allocate the tvlv, put the tt_data and all the tt_vlan_data
		 * in the initial part
		 */
		tt_len = -1;
		tvlv_len = batadv_tt_prepare_tvlv_global_data(req_dst_orig_node,
							      &tvlv_tt_data,
							      &tt_change,
							      &tt_len);
		if (!tt_len)
			goto out;

		/* fill the rest of the tvlv with the real TT entries */
		batadv_tt_tvlv_generate(bat_priv, bat_priv->tt.global_hash,
					tt_change, tt_len,
					batadv_tt_global_valid,
					req_dst_orig_node);
	}

	/* Don't send the response, if larger than fragmented packet. */
	tt_len = sizeof(struct batadv_unicast_tvlv_packet) + tvlv_len;
	if (tt_len > atomic_read(&bat_priv->packet_size_max)) {
		net_ratelimited_function(batadv_info, bat_priv->soft_iface,
					 "Ignoring TT_REQUEST from %pM; Response size exceeds max packet size.\n",
					 res_dst_orig_node->orig);
		goto out;
	}

	tvlv_tt_data->flags = BATADV_TT_RESPONSE;
	tvlv_tt_data->ttvn = req_ttvn;

	if (full_table)
		tvlv_tt_data->flags |= BATADV_TT_FULL_TABLE;

	batadv_dbg(BATADV_DBG_TT, bat_priv,
		   "Sending TT_RESPONSE %pM for %pM [%c] (ttvn: %u)\n",
		   res_dst_orig_node->orig, req_dst_orig_node->orig,
		   full_table ? 'F' : '.', req_ttvn);

	batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_TX);

	batadv_tvlv_unicast_send(bat_priv, req_dst_orig_node->orig,
				 req_src, BATADV_TVLV_TT, 1, tvlv_tt_data,
				 tvlv_len);

	ret = true;
	goto out;

unlock:
	spin_unlock_bh(&req_dst_orig_node->tt_buff_lock);

out:
	if (res_dst_orig_node)
		batadv_orig_node_free_ref(res_dst_orig_node);
	if (req_dst_orig_node)
		batadv_orig_node_free_ref(req_dst_orig_node);
	kfree(tvlv_tt_data);
	return ret;
}

/**
 * batadv_send_my_tt_response - send reply to tt request concerning this node's
 *  translation table
 * @bat_priv: the bat priv with all the soft interface information
 * @tt_data: tt data containing the tt request information
 * @req_src: mac address of tt request sender
 *
 * Returns true if tt request reply was sent, false otherwise.
 */
static bool batadv_send_my_tt_response(struct batadv_priv *bat_priv,
				       struct batadv_tvlv_tt_data *tt_data,
				       uint8_t *req_src)
{
	struct batadv_tvlv_tt_data *tvlv_tt_data = NULL;
	struct batadv_hard_iface *primary_if = NULL;
	struct batadv_tvlv_tt_change *tt_change;
	struct batadv_orig_node *orig_node;
	uint8_t my_ttvn, req_ttvn;
	uint16_t tvlv_len;
	bool full_table;
	int32_t tt_len;

	batadv_dbg(BATADV_DBG_TT, bat_priv,
		   "Received TT_REQUEST from %pM for ttvn: %u (me) [%c]\n",
		   req_src, tt_data->ttvn,
		   ((tt_data->flags & BATADV_TT_FULL_TABLE) ? 'F' : '.'));

	spin_lock_bh(&bat_priv->tt.commit_lock);

	my_ttvn = (uint8_t)atomic_read(&bat_priv->tt.vn);
	req_ttvn = tt_data->ttvn;

	orig_node = batadv_orig_hash_find(bat_priv, req_src);
	if (!orig_node)
		goto out;

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

	/* If the full table has been explicitly requested or the gap
	 * is too big send the whole local translation table
	 */
	if (tt_data->flags & BATADV_TT_FULL_TABLE || my_ttvn != req_ttvn ||
	    !bat_priv->tt.last_changeset)
		full_table = true;
	else
		full_table = false;

	/* TT fragmentation hasn't been implemented yet, so send as many
	 * TT entries fit a single packet as possible only
	 */
	if (!full_table) {
		spin_lock_bh(&bat_priv->tt.last_changeset_lock);

		tt_len = bat_priv->tt.last_changeset_len;
		tvlv_len = batadv_tt_prepare_tvlv_local_data(bat_priv,
							     &tvlv_tt_data,
							     &tt_change,
							     &tt_len);
		if (!tt_len)
			goto unlock;

		/* Copy the last orig_node's OGM buffer */
		memcpy(tt_change, bat_priv->tt.last_changeset,
		       bat_priv->tt.last_changeset_len);
		spin_unlock_bh(&bat_priv->tt.last_changeset_lock);
	} else {
		req_ttvn = (uint8_t)atomic_read(&bat_priv->tt.vn);

		/* allocate the tvlv, put the tt_data and all the tt_vlan_data
		 * in the initial part
		 */
		tt_len = -1;
		tvlv_len = batadv_tt_prepare_tvlv_local_data(bat_priv,
							     &tvlv_tt_data,
							     &tt_change,
							     &tt_len);
		if (!tt_len)
			goto out;

		/* fill the rest of the tvlv with the real TT entries */
		batadv_tt_tvlv_generate(bat_priv, bat_priv->tt.local_hash,
					tt_change, tt_len,
					batadv_tt_local_valid, NULL);
	}

	tvlv_tt_data->flags = BATADV_TT_RESPONSE;
	tvlv_tt_data->ttvn = req_ttvn;

	if (full_table)
		tvlv_tt_data->flags |= BATADV_TT_FULL_TABLE;

	batadv_dbg(BATADV_DBG_TT, bat_priv,
		   "Sending TT_RESPONSE to %pM [%c] (ttvn: %u)\n",
		   orig_node->orig, full_table ? 'F' : '.', req_ttvn);

	batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_TX);

	batadv_tvlv_unicast_send(bat_priv, primary_if->net_dev->dev_addr,
				 req_src, BATADV_TVLV_TT, 1, tvlv_tt_data,
				 tvlv_len);

	goto out;

unlock:
	spin_unlock_bh(&bat_priv->tt.last_changeset_lock);
out:
	spin_unlock_bh(&bat_priv->tt.commit_lock);
	if (orig_node)
		batadv_orig_node_free_ref(orig_node);
	if (primary_if)
		batadv_hardif_free_ref(primary_if);
	kfree(tvlv_tt_data);
	/* The packet was for this host, so it doesn't need to be re-routed */
	return true;
}

/**
 * batadv_send_tt_response - send reply to tt request
 * @bat_priv: the bat priv with all the soft interface information
 * @tt_data: tt data containing the tt request information
 * @req_src: mac address of tt request sender
 * @req_dst: mac address of tt request recipient
 *
 * Returns true if tt request reply was sent, false otherwise.
 */
static bool batadv_send_tt_response(struct batadv_priv *bat_priv,
				    struct batadv_tvlv_tt_data *tt_data,
				    uint8_t *req_src, uint8_t *req_dst)
{
	if (batadv_is_my_mac(bat_priv, req_dst))
		return batadv_send_my_tt_response(bat_priv, tt_data, req_src);
	return batadv_send_other_tt_response(bat_priv, tt_data, req_src,
					     req_dst);
}

static void _batadv_tt_update_changes(struct batadv_priv *bat_priv,
				      struct batadv_orig_node *orig_node,
				      struct batadv_tvlv_tt_change *tt_change,
				      uint16_t tt_num_changes, uint8_t ttvn)
{
	int i;
	int roams;

	for (i = 0; i < tt_num_changes; i++) {
		if ((tt_change + i)->flags & BATADV_TT_CLIENT_DEL) {
			roams = (tt_change + i)->flags & BATADV_TT_CLIENT_ROAM;
			batadv_tt_global_del(bat_priv, orig_node,
					     (tt_change + i)->addr,
					     ntohs((tt_change + i)->vid),
					     "tt removed by changes",
					     roams);
		} else {
			if (!batadv_tt_global_add(bat_priv, orig_node,
						  (tt_change + i)->addr,
						  ntohs((tt_change + i)->vid),
						  (tt_change + i)->flags, ttvn))
				/* In case of problem while storing a
				 * global_entry, we stop the updating
				 * procedure without committing the
				 * ttvn change. This will avoid to send
				 * corrupted data on tt_request
				 */
				return;
		}
	}
	orig_node->capa_initialized |= BATADV_ORIG_CAPA_HAS_TT;
}

static void batadv_tt_fill_gtable(struct batadv_priv *bat_priv,
				  struct batadv_tvlv_tt_change *tt_change,
				  uint8_t ttvn, uint8_t *resp_src,
				  uint16_t num_entries)
{
	struct batadv_orig_node *orig_node;

	orig_node = batadv_orig_hash_find(bat_priv, resp_src);
	if (!orig_node)
		goto out;

	/* Purge the old table first.. */
	batadv_tt_global_del_orig(bat_priv, orig_node, -1,
				  "Received full table");

	_batadv_tt_update_changes(bat_priv, orig_node, tt_change, num_entries,
				  ttvn);

	spin_lock_bh(&orig_node->tt_buff_lock);
	kfree(orig_node->tt_buff);
	orig_node->tt_buff_len = 0;
	orig_node->tt_buff = NULL;
	spin_unlock_bh(&orig_node->tt_buff_lock);

	atomic_set(&orig_node->last_ttvn, ttvn);

out:
	if (orig_node)
		batadv_orig_node_free_ref(orig_node);
}

static void batadv_tt_update_changes(struct batadv_priv *bat_priv,
				     struct batadv_orig_node *orig_node,
				     uint16_t tt_num_changes, uint8_t ttvn,
				     struct batadv_tvlv_tt_change *tt_change)
{
	_batadv_tt_update_changes(bat_priv, orig_node, tt_change,
				  tt_num_changes, ttvn);

	batadv_tt_save_orig_buffer(bat_priv, orig_node, tt_change,
				   batadv_tt_len(tt_num_changes));
	atomic_set(&orig_node->last_ttvn, ttvn);
}

/**
 * batadv_is_my_client - check if a client is served by the local node
 * @bat_priv: the bat priv with all the soft interface information
 * @addr: the mac address of the client to check
 * @vid: VLAN identifier
 *
 * Returns true if the client is served by this node, false otherwise.
 */
bool batadv_is_my_client(struct batadv_priv *bat_priv, const uint8_t *addr,
			 unsigned short vid)
{
	struct batadv_tt_local_entry *tt_local_entry;
	bool ret = false;

	tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr, vid);
	if (!tt_local_entry)
		goto out;
	/* Check if the client has been logically deleted (but is kept for
	 * consistency purpose)
	 */
	if ((tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING) ||
	    (tt_local_entry->common.flags & BATADV_TT_CLIENT_ROAM))
		goto out;
	ret = true;
out:
	if (tt_local_entry)
		batadv_tt_local_entry_free_ref(tt_local_entry);
	return ret;
}

/**
 * batadv_handle_tt_response - process incoming tt reply
 * @bat_priv: the bat priv with all the soft interface information
 * @tt_data: tt data containing the tt request information
 * @resp_src: mac address of tt reply sender
 * @num_entries: number of tt change entries appended to the tt data
 */
static void batadv_handle_tt_response(struct batadv_priv *bat_priv,
				      struct batadv_tvlv_tt_data *tt_data,
				      uint8_t *resp_src, uint16_t num_entries)
{
	struct batadv_tt_req_node *node, *safe;
	struct batadv_orig_node *orig_node = NULL;
	struct batadv_tvlv_tt_change *tt_change;
	uint8_t *tvlv_ptr = (uint8_t *)tt_data;
	uint16_t change_offset;

	batadv_dbg(BATADV_DBG_TT, bat_priv,
		   "Received TT_RESPONSE from %pM for ttvn %d t_size: %d [%c]\n",
		   resp_src, tt_data->ttvn, num_entries,
		   ((tt_data->flags & BATADV_TT_FULL_TABLE) ? 'F' : '.'));

	orig_node = batadv_orig_hash_find(bat_priv, resp_src);
	if (!orig_node)
		goto out;

	spin_lock_bh(&orig_node->tt_lock);

	change_offset = sizeof(struct batadv_tvlv_tt_vlan_data);
	change_offset *= ntohs(tt_data->num_vlan);
	change_offset += sizeof(*tt_data);
	tvlv_ptr += change_offset;

	tt_change = (struct batadv_tvlv_tt_change *)tvlv_ptr;
	if (tt_data->flags & BATADV_TT_FULL_TABLE) {
		batadv_tt_fill_gtable(bat_priv, tt_change, tt_data->ttvn,
				      resp_src, num_entries);
	} else {
		batadv_tt_update_changes(bat_priv, orig_node, num_entries,
					 tt_data->ttvn, tt_change);
	}

	/* Recalculate the CRC for this orig_node and store it */
	batadv_tt_global_update_crc(bat_priv, orig_node);

	spin_unlock_bh(&orig_node->tt_lock);

	/* Delete the tt_req_node from pending tt_requests list */
	spin_lock_bh(&bat_priv->tt.req_list_lock);
	list_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
		if (!batadv_compare_eth(node->addr, resp_src))
			continue;
		list_del(&node->list);
		kfree(node);
	}

	spin_unlock_bh(&bat_priv->tt.req_list_lock);
out:
	if (orig_node)
		batadv_orig_node_free_ref(orig_node);
}

static void batadv_tt_roam_list_free(struct batadv_priv *bat_priv)
{
	struct batadv_tt_roam_node *node, *safe;

	spin_lock_bh(&bat_priv->tt.roam_list_lock);

	list_for_each_entry_safe(node, safe, &bat_priv->tt.roam_list, list) {
		list_del(&node->list);
		kfree(node);
	}

	spin_unlock_bh(&bat_priv->tt.roam_list_lock);
}

static void batadv_tt_roam_purge(struct batadv_priv *bat_priv)
{
	struct batadv_tt_roam_node *node, *safe;

	spin_lock_bh(&bat_priv->tt.roam_list_lock);
	list_for_each_entry_safe(node, safe, &bat_priv->tt.roam_list, list) {
		if (!batadv_has_timed_out(node->first_time,
					  BATADV_ROAMING_MAX_TIME))
			continue;

		list_del(&node->list);
		kfree(node);
	}
	spin_unlock_bh(&bat_priv->tt.roam_list_lock);
}

/* This function checks whether the client already reached the
 * maximum number of possible roaming phases. In this case the ROAMING_ADV
 * will not be sent.
 *
 * returns true if the ROAMING_ADV can be sent, false otherwise
 */
static bool batadv_tt_check_roam_count(struct batadv_priv *bat_priv,
				       uint8_t *client)
{
	struct batadv_tt_roam_node *tt_roam_node;
	bool ret = false;

	spin_lock_bh(&bat_priv->tt.roam_list_lock);
	/* The new tt_req will be issued only if I'm not waiting for a
	 * reply from the same orig_node yet
	 */
	list_for_each_entry(tt_roam_node, &bat_priv->tt.roam_list, list) {
		if (!batadv_compare_eth(tt_roam_node->addr, client))
			continue;

		if (batadv_has_timed_out(tt_roam_node->first_time,
					 BATADV_ROAMING_MAX_TIME))
			continue;

		if (!batadv_atomic_dec_not_zero(&tt_roam_node->counter))
			/* Sorry, you roamed too many times! */
			goto unlock;
		ret = true;
		break;
	}

	if (!ret) {
		tt_roam_node = kmalloc(sizeof(*tt_roam_node), GFP_ATOMIC);
		if (!tt_roam_node)
			goto unlock;

		tt_roam_node->first_time = jiffies;
		atomic_set(&tt_roam_node->counter,
			   BATADV_ROAMING_MAX_COUNT - 1);
		ether_addr_copy(tt_roam_node->addr, client);

		list_add(&tt_roam_node->list, &bat_priv->tt.roam_list);
		ret = true;
	}

unlock:
	spin_unlock_bh(&bat_priv->tt.roam_list_lock);
	return ret;
}

/**
 * batadv_send_roam_adv - send a roaming advertisement message
 * @bat_priv: the bat priv with all the soft interface information
 * @client: mac address of the roaming client
 * @vid: VLAN identifier
 * @orig_node: message destination
 *
 * Send a ROAMING_ADV message to the node which was previously serving this
 * client. This is done to inform the node that from now on all traffic destined
 * for this particular roamed client has to be forwarded to the sender of the
 * roaming message.
 */
static void batadv_send_roam_adv(struct batadv_priv *bat_priv, uint8_t *client,
				 unsigned short vid,
				 struct batadv_orig_node *orig_node)
{
	struct batadv_hard_iface *primary_if;
	struct batadv_tvlv_roam_adv tvlv_roam;

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

	/* before going on we have to check whether the client has
	 * already roamed to us too many times
	 */
	if (!batadv_tt_check_roam_count(bat_priv, client))
		goto out;

	batadv_dbg(BATADV_DBG_TT, bat_priv,
		   "Sending ROAMING_ADV to %pM (client %pM, vid: %d)\n",
		   orig_node->orig, client, BATADV_PRINT_VID(vid));

	batadv_inc_counter(bat_priv, BATADV_CNT_TT_ROAM_ADV_TX);

	memcpy(tvlv_roam.client, client, sizeof(tvlv_roam.client));
	tvlv_roam.vid = htons(vid);

	batadv_tvlv_unicast_send(bat_priv, primary_if->net_dev->dev_addr,
				 orig_node->orig, BATADV_TVLV_ROAM, 1,
				 &tvlv_roam, sizeof(tvlv_roam));

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

static void batadv_tt_purge(struct work_struct *work)
{
	struct delayed_work *delayed_work;
	struct batadv_priv_tt *priv_tt;
	struct batadv_priv *bat_priv;

	delayed_work = container_of(work, struct delayed_work, work);
	priv_tt = container_of(delayed_work, struct batadv_priv_tt, work);
	bat_priv = container_of(priv_tt, struct batadv_priv, tt);

	batadv_tt_local_purge(bat_priv, BATADV_TT_LOCAL_TIMEOUT);
	batadv_tt_global_purge(bat_priv);
	batadv_tt_req_purge(bat_priv);
	batadv_tt_roam_purge(bat_priv);

	queue_delayed_work(batadv_event_workqueue, &bat_priv->tt.work,
			   msecs_to_jiffies(BATADV_TT_WORK_PERIOD));
}

void batadv_tt_free(struct batadv_priv *bat_priv)
{
	batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_TT, 1);
	batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_TT, 1);

	cancel_delayed_work_sync(&bat_priv->tt.work);

	batadv_tt_local_table_free(bat_priv);
	batadv_tt_global_table_free(bat_priv);
	batadv_tt_req_list_free(bat_priv);
	batadv_tt_changes_list_free(bat_priv);
	batadv_tt_roam_list_free(bat_priv);

	kfree(bat_priv->tt.last_changeset);
}

/**
 * batadv_tt_local_set_flags - set or unset the specified flags on the local
 *  table and possibly count them in the TT size
 * @bat_priv: the bat priv with all the soft interface information
 * @flags: the flag to switch
 * @enable: whether to set or unset the flag
 * @count: whether to increase the TT size by the number of changed entries
 */
static void batadv_tt_local_set_flags(struct batadv_priv *bat_priv,
				      uint16_t flags, bool enable, bool count)
{
	struct batadv_hashtable *hash = bat_priv->tt.local_hash;
	struct batadv_tt_common_entry *tt_common_entry;
	uint16_t changed_num = 0;
	struct hlist_head *head;
	uint32_t i;

	if (!hash)
		return;

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

		rcu_read_lock();
		hlist_for_each_entry_rcu(tt_common_entry,
					 head, hash_entry) {
			if (enable) {
				if ((tt_common_entry->flags & flags) == flags)
					continue;
				tt_common_entry->flags |= flags;
			} else {
				if (!(tt_common_entry->flags & flags))
					continue;
				tt_common_entry->flags &= ~flags;
			}
			changed_num++;

			if (!count)
				continue;

			batadv_tt_local_size_inc(bat_priv,
						 tt_common_entry->vid);
		}
		rcu_read_unlock();
	}
}

/* Purge out all the tt local entries marked with BATADV_TT_CLIENT_PENDING */
static void batadv_tt_local_purge_pending_clients(struct batadv_priv *bat_priv)
{
	struct batadv_hashtable *hash = bat_priv->tt.local_hash;
	struct batadv_tt_common_entry *tt_common;
	struct batadv_tt_local_entry *tt_local;
	struct batadv_softif_vlan *vlan;
	struct hlist_node *node_tmp;
	struct hlist_head *head;
	spinlock_t *list_lock; /* protects write access to the hash lists */
	uint32_t i;

	if (!hash)
		return;

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

		spin_lock_bh(list_lock);
		hlist_for_each_entry_safe(tt_common, node_tmp, head,
					  hash_entry) {
			if (!(tt_common->flags & BATADV_TT_CLIENT_PENDING))
				continue;

			batadv_dbg(BATADV_DBG_TT, bat_priv,
				   "Deleting local tt entry (%pM, vid: %d): pending\n",
				   tt_common->addr,
				   BATADV_PRINT_VID(tt_common->vid));

			batadv_tt_local_size_dec(bat_priv, tt_common->vid);
			hlist_del_rcu(&tt_common->hash_entry);
			tt_local = container_of(tt_common,
						struct batadv_tt_local_entry,
						common);

			/* decrease the reference held for this vlan */
			vlan = batadv_softif_vlan_get(bat_priv, tt_common->vid);
			batadv_softif_vlan_free_ref(vlan);
			batadv_softif_vlan_free_ref(vlan);

			batadv_tt_local_entry_free_ref(tt_local);
		}
		spin_unlock_bh(list_lock);
	}
}

/**
 * batadv_tt_local_commit_changes_nolock - commit all pending local tt changes
 *  which have been queued in the time since the last commit
 * @bat_priv: the bat priv with all the soft interface information
 *
 * Caller must hold tt->commit_lock.
 */
static void batadv_tt_local_commit_changes_nolock(struct batadv_priv *bat_priv)
{
	/* Update multicast addresses in local translation table */
	batadv_mcast_mla_update(bat_priv);

	if (atomic_read(&bat_priv->tt.local_changes) < 1) {
		if (!batadv_atomic_dec_not_zero(&bat_priv->tt.ogm_append_cnt))
			batadv_tt_tvlv_container_update(bat_priv);
		return;
	}

	batadv_tt_local_set_flags(bat_priv, BATADV_TT_CLIENT_NEW, false, true);

	batadv_tt_local_purge_pending_clients(bat_priv);
	batadv_tt_local_update_crc(bat_priv);

	/* Increment the TTVN only once per OGM interval */
	atomic_inc(&bat_priv->tt.vn);
	batadv_dbg(BATADV_DBG_TT, bat_priv,
		   "Local changes committed, updating to ttvn %u\n",
		   (uint8_t)atomic_read(&bat_priv->tt.vn));

	/* reset the sending counter */
	atomic_set(&bat_priv->tt.ogm_append_cnt, BATADV_TT_OGM_APPEND_MAX);
	batadv_tt_tvlv_container_update(bat_priv);
}

/**
 * batadv_tt_local_commit_changes - commit all pending local tt changes which
 *  have been queued in the time since the last commit
 * @bat_priv: the bat priv with all the soft interface information
 */
void batadv_tt_local_commit_changes(struct batadv_priv *bat_priv)
{
	spin_lock_bh(&bat_priv->tt.commit_lock);
	batadv_tt_local_commit_changes_nolock(bat_priv);
	spin_unlock_bh(&bat_priv->tt.commit_lock);
}

bool batadv_is_ap_isolated(struct batadv_priv *bat_priv, uint8_t *src,
			   uint8_t *dst, unsigned short vid)
{
	struct batadv_tt_local_entry *tt_local_entry = NULL;
	struct batadv_tt_global_entry *tt_global_entry = NULL;
	struct batadv_softif_vlan *vlan;
	bool ret = false;

	vlan = batadv_softif_vlan_get(bat_priv, vid);
	if (!vlan || !atomic_read(&vlan->ap_isolation))
		goto out;

	tt_local_entry = batadv_tt_local_hash_find(bat_priv, dst, vid);
	if (!tt_local_entry)
		goto out;

	tt_global_entry = batadv_tt_global_hash_find(bat_priv, src, vid);
	if (!tt_global_entry)
		goto out;

	if (!_batadv_is_ap_isolated(tt_local_entry, tt_global_entry))
		goto out;

	ret = true;

out:
	if (vlan)
		batadv_softif_vlan_free_ref(vlan);
	if (tt_global_entry)
		batadv_tt_global_entry_free_ref(tt_global_entry);
	if (tt_local_entry)
		batadv_tt_local_entry_free_ref(tt_local_entry);
	return ret;
}

/**
 * batadv_tt_update_orig - update global translation table with new tt
 *  information received via ogms
 * @bat_priv: the bat priv with all the soft interface information
 * @orig: the orig_node of the ogm
 * @tt_vlan: pointer to the first tvlv VLAN entry
 * @tt_num_vlan: number of tvlv VLAN entries
 * @tt_change: pointer to the first entry in the TT buffer
 * @tt_num_changes: number of tt changes inside the tt buffer
 * @ttvn: translation table version number of this changeset
 * @tt_crc: crc32 checksum of orig node's translation table
 */
static void batadv_tt_update_orig(struct batadv_priv *bat_priv,
				  struct batadv_orig_node *orig_node,
				  const void *tt_buff, uint16_t tt_num_vlan,
				  struct batadv_tvlv_tt_change *tt_change,
				  uint16_t tt_num_changes, uint8_t ttvn)
{
	uint8_t orig_ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn);
	struct batadv_tvlv_tt_vlan_data *tt_vlan;
	bool full_table = true;
	bool has_tt_init;

	tt_vlan = (struct batadv_tvlv_tt_vlan_data *)tt_buff;
	has_tt_init = orig_node->capa_initialized & BATADV_ORIG_CAPA_HAS_TT;

	/* orig table not initialised AND first diff is in the OGM OR the ttvn
	 * increased by one -> we can apply the attached changes
	 */
	if ((!has_tt_init && ttvn == 1) || ttvn - orig_ttvn == 1) {
		/* the OGM could not contain the changes due to their size or
		 * because they have already been sent BATADV_TT_OGM_APPEND_MAX
		 * times.
		 * In this case send a tt request
		 */
		if (!tt_num_changes) {
			full_table = false;
			goto request_table;
		}

		spin_lock_bh(&orig_node->tt_lock);

		batadv_tt_update_changes(bat_priv, orig_node, tt_num_changes,
					 ttvn, tt_change);

		/* Even if we received the precomputed crc with the OGM, we
		 * prefer to recompute it to spot any possible inconsistency
		 * in the global table
		 */
		batadv_tt_global_update_crc(bat_priv, orig_node);

		spin_unlock_bh(&orig_node->tt_lock);

		/* The ttvn alone is not enough to guarantee consistency
		 * because a single value could represent different states
		 * (due to the wrap around). Thus a node has to check whether
		 * the resulting table (after applying the changes) is still
		 * consistent or not. E.g. a node could disconnect while its
		 * ttvn is X and reconnect on ttvn = X + TTVN_MAX: in this case
		 * checking the CRC value is mandatory to detect the
		 * inconsistency
		 */
		if (!batadv_tt_global_check_crc(orig_node, tt_vlan,
						tt_num_vlan))
			goto request_table;
	} else {
		/* if we missed more than one change or our tables are not
		 * in sync anymore -> request fresh tt data
		 */
		if (!has_tt_init || ttvn != orig_ttvn ||
		    !batadv_tt_global_check_crc(orig_node, tt_vlan,
						tt_num_vlan)) {
request_table:
			batadv_dbg(BATADV_DBG_TT, bat_priv,
				   "TT inconsistency for %pM. Need to retrieve the correct information (ttvn: %u last_ttvn: %u num_changes: %u)\n",
				   orig_node->orig, ttvn, orig_ttvn,
				   tt_num_changes);
			batadv_send_tt_request(bat_priv, orig_node, ttvn,
					       tt_vlan, tt_num_vlan,
					       full_table);
			return;
		}
	}
}

/**
 * batadv_tt_global_client_is_roaming - check if a client is marked as roaming
 * @bat_priv: the bat priv with all the soft interface information
 * @addr: the mac address of the client to check
 * @vid: VLAN identifier
 *
 * Returns true if we know that the client has moved from its old originator
 * to another one. This entry is still kept for consistency purposes and will be
 * deleted later by a DEL or because of timeout
 */
bool batadv_tt_global_client_is_roaming(struct batadv_priv *bat_priv,
					uint8_t *addr, unsigned short vid)
{
	struct batadv_tt_global_entry *tt_global_entry;
	bool ret = false;

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

	ret = tt_global_entry->common.flags & BATADV_TT_CLIENT_ROAM;
	batadv_tt_global_entry_free_ref(tt_global_entry);
out:
	return ret;
}

/**
 * batadv_tt_local_client_is_roaming - tells whether the client is roaming
 * @bat_priv: the bat priv with all the soft interface information
 * @addr: the mac address of the local client to query
 * @vid: VLAN identifier
 *
 * Returns true if the local client is known to be roaming (it is not served by
 * this node anymore) or not. If yes, the client is still present in the table
 * to keep the latter consistent with the node TTVN
 */
bool batadv_tt_local_client_is_roaming(struct batadv_priv *bat_priv,
				       uint8_t *addr, unsigned short vid)
{
	struct batadv_tt_local_entry *tt_local_entry;
	bool ret = false;

	tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr, vid);
	if (!tt_local_entry)
		goto out;

	ret = tt_local_entry->common.flags & BATADV_TT_CLIENT_ROAM;
	batadv_tt_local_entry_free_ref(tt_local_entry);
out:
	return ret;
}

bool batadv_tt_add_temporary_global_entry(struct batadv_priv *bat_priv,
					  struct batadv_orig_node *orig_node,
					  const unsigned char *addr,
					  unsigned short vid)
{
	bool ret = false;

	if (!batadv_tt_global_add(bat_priv, orig_node, addr, vid,
				  BATADV_TT_CLIENT_TEMP,
				  atomic_read(&orig_node->last_ttvn)))
		goto out;

	batadv_dbg(BATADV_DBG_TT, bat_priv,
		   "Added temporary global client (addr: %pM, vid: %d, orig: %pM)\n",
		   addr, BATADV_PRINT_VID(vid), orig_node->orig);
	ret = true;
out:
	return ret;
}

/**
 * batadv_tt_local_resize_to_mtu - resize the local translation table fit the
 *  maximum packet size that can be transported through the mesh
 * @soft_iface: netdev struct of the mesh interface
 *
 * Remove entries older than 'timeout' and half timeout if more entries need
 * to be removed.
 */
void batadv_tt_local_resize_to_mtu(struct net_device *soft_iface)
{
	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
	int packet_size_max = atomic_read(&bat_priv->packet_size_max);
	int table_size, timeout = BATADV_TT_LOCAL_TIMEOUT / 2;
	bool reduced = false;

	spin_lock_bh(&bat_priv->tt.commit_lock);

	while (true) {
		table_size = batadv_tt_local_table_transmit_size(bat_priv);
		if (packet_size_max >= table_size)
			break;

		batadv_tt_local_purge(bat_priv, timeout);
		batadv_tt_local_purge_pending_clients(bat_priv);

		timeout /= 2;
		reduced = true;
		net_ratelimited_function(batadv_info, soft_iface,
					 "Forced to purge local tt entries to fit new maximum fragment MTU (%i)\n",
					 packet_size_max);
	}

	/* commit these changes immediately, to avoid synchronization problem
	 * with the TTVN
	 */
	if (reduced)
		batadv_tt_local_commit_changes_nolock(bat_priv);

	spin_unlock_bh(&bat_priv->tt.commit_lock);
}

/**
 * batadv_tt_tvlv_ogm_handler_v1 - process incoming tt 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 gateway data
 * @tvlv_value_len: tvlv buffer length
 */
static void batadv_tt_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
					  struct batadv_orig_node *orig,
					  uint8_t flags, void *tvlv_value,
					  uint16_t tvlv_value_len)
{
	struct batadv_tvlv_tt_vlan_data *tt_vlan;
	struct batadv_tvlv_tt_change *tt_change;
	struct batadv_tvlv_tt_data *tt_data;
	uint16_t num_entries, num_vlan;

	if (tvlv_value_len < sizeof(*tt_data))
		return;

	tt_data = (struct batadv_tvlv_tt_data *)tvlv_value;
	tvlv_value_len -= sizeof(*tt_data);

	num_vlan = ntohs(tt_data->num_vlan);

	if (tvlv_value_len < sizeof(*tt_vlan) * num_vlan)
		return;

	tt_vlan = (struct batadv_tvlv_tt_vlan_data *)(tt_data + 1);
	tt_change = (struct batadv_tvlv_tt_change *)(tt_vlan + num_vlan);
	tvlv_value_len -= sizeof(*tt_vlan) * num_vlan;

	num_entries = batadv_tt_entries(tvlv_value_len);

	batadv_tt_update_orig(bat_priv, orig, tt_vlan, num_vlan, tt_change,
			      num_entries, tt_data->ttvn);
}

/**
 * batadv_tt_tvlv_unicast_handler_v1 - process incoming (unicast) tt tvlv
 *  container
 * @bat_priv: the bat priv with all the soft interface information
 * @src: mac address of tt tvlv sender
 * @dst: mac address of tt tvlv recipient
 * @tvlv_value: tvlv buffer containing the tt data
 * @tvlv_value_len: tvlv buffer length
 *
 * Returns NET_RX_DROP if the tt tvlv is to be re-routed, NET_RX_SUCCESS
 * otherwise.
 */
static int batadv_tt_tvlv_unicast_handler_v1(struct batadv_priv *bat_priv,
					     uint8_t *src, uint8_t *dst,
					     void *tvlv_value,
					     uint16_t tvlv_value_len)
{
	struct batadv_tvlv_tt_data *tt_data;
	uint16_t tt_vlan_len, tt_num_entries;
	char tt_flag;
	bool ret;

	if (tvlv_value_len < sizeof(*tt_data))
		return NET_RX_SUCCESS;

	tt_data = (struct batadv_tvlv_tt_data *)tvlv_value;
	tvlv_value_len -= sizeof(*tt_data);

	tt_vlan_len = sizeof(struct batadv_tvlv_tt_vlan_data);
	tt_vlan_len *= ntohs(tt_data->num_vlan);

	if (tvlv_value_len < tt_vlan_len)
		return NET_RX_SUCCESS;

	tvlv_value_len -= tt_vlan_len;
	tt_num_entries = batadv_tt_entries(tvlv_value_len);

	switch (tt_data->flags & BATADV_TT_DATA_TYPE_MASK) {
	case BATADV_TT_REQUEST:
		batadv_inc_counter(bat_priv, BATADV_CNT_TT_REQUEST_RX);

		/* If this node cannot provide a TT response the tt_request is
		 * forwarded
		 */
		ret = batadv_send_tt_response(bat_priv, tt_data, src, dst);
		if (!ret) {
			if (tt_data->flags & BATADV_TT_FULL_TABLE)
				tt_flag = 'F';
			else
				tt_flag = '.';

			batadv_dbg(BATADV_DBG_TT, bat_priv,
				   "Routing TT_REQUEST to %pM [%c]\n",
				   dst, tt_flag);
			/* tvlv API will re-route the packet */
			return NET_RX_DROP;
		}
		break;
	case BATADV_TT_RESPONSE:
		batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_RX);

		if (batadv_is_my_mac(bat_priv, dst)) {
			batadv_handle_tt_response(bat_priv, tt_data,
						  src, tt_num_entries);
			return NET_RX_SUCCESS;
		}

		if (tt_data->flags & BATADV_TT_FULL_TABLE)
			tt_flag =  'F';
		else
			tt_flag = '.';

		batadv_dbg(BATADV_DBG_TT, bat_priv,
			   "Routing TT_RESPONSE to %pM [%c]\n", dst, tt_flag);

		/* tvlv API will re-route the packet */
		return NET_RX_DROP;
	}

	return NET_RX_SUCCESS;
}

/**
 * batadv_roam_tvlv_unicast_handler_v1 - process incoming tt roam tvlv container
 * @bat_priv: the bat priv with all the soft interface information
 * @src: mac address of tt tvlv sender
 * @dst: mac address of tt tvlv recipient
 * @tvlv_value: tvlv buffer containing the tt data
 * @tvlv_value_len: tvlv buffer length
 *
 * Returns NET_RX_DROP if the tt roam tvlv is to be re-routed, NET_RX_SUCCESS
 * otherwise.
 */
static int batadv_roam_tvlv_unicast_handler_v1(struct batadv_priv *bat_priv,
					       uint8_t *src, uint8_t *dst,
					       void *tvlv_value,
					       uint16_t tvlv_value_len)
{
	struct batadv_tvlv_roam_adv *roaming_adv;
	struct batadv_orig_node *orig_node = NULL;

	/* If this node is not the intended recipient of the
	 * roaming advertisement the packet is forwarded
	 * (the tvlv API will re-route the packet).
	 */
	if (!batadv_is_my_mac(bat_priv, dst))
		return NET_RX_DROP;

	if (tvlv_value_len < sizeof(*roaming_adv))
		goto out;

	orig_node = batadv_orig_hash_find(bat_priv, src);
	if (!orig_node)
		goto out;

	batadv_inc_counter(bat_priv, BATADV_CNT_TT_ROAM_ADV_RX);
	roaming_adv = (struct batadv_tvlv_roam_adv *)tvlv_value;

	batadv_dbg(BATADV_DBG_TT, bat_priv,
		   "Received ROAMING_ADV from %pM (client %pM)\n",
		   src, roaming_adv->client);

	batadv_tt_global_add(bat_priv, orig_node, roaming_adv->client,
			     ntohs(roaming_adv->vid), BATADV_TT_CLIENT_ROAM,
			     atomic_read(&orig_node->last_ttvn) + 1);

out:
	if (orig_node)
		batadv_orig_node_free_ref(orig_node);
	return NET_RX_SUCCESS;
}

/**
 * batadv_tt_init - initialise the translation table internals
 * @bat_priv: the bat priv with all the soft interface information
 *
 * Return 0 on success or negative error number in case of failure.
 */
int batadv_tt_init(struct batadv_priv *bat_priv)
{
	int ret;

	/* synchronized flags must be remote */
	BUILD_BUG_ON(!(BATADV_TT_SYNC_MASK & BATADV_TT_REMOTE_MASK));

	ret = batadv_tt_local_init(bat_priv);
	if (ret < 0)
		return ret;

	ret = batadv_tt_global_init(bat_priv);
	if (ret < 0)
		return ret;

	batadv_tvlv_handler_register(bat_priv, batadv_tt_tvlv_ogm_handler_v1,
				     batadv_tt_tvlv_unicast_handler_v1,
				     BATADV_TVLV_TT, 1, BATADV_NO_FLAGS);

	batadv_tvlv_handler_register(bat_priv, NULL,
				     batadv_roam_tvlv_unicast_handler_v1,
				     BATADV_TVLV_ROAM, 1, BATADV_NO_FLAGS);

	INIT_DELAYED_WORK(&bat_priv->tt.work, batadv_tt_purge);
	queue_delayed_work(batadv_event_workqueue, &bat_priv->tt.work,
			   msecs_to_jiffies(BATADV_TT_WORK_PERIOD));

	return 1;
}

/**
 * batadv_tt_global_is_isolated - check if a client is marked as isolated
 * @bat_priv: the bat priv with all the soft interface information
 * @addr: the mac address of the client
 * @vid: the identifier of the VLAN where this client is connected
 *
 * Returns true if the client is marked with the TT_CLIENT_ISOLA flag, false
 * otherwise
 */
bool batadv_tt_global_is_isolated(struct batadv_priv *bat_priv,
				  const uint8_t *addr, unsigned short vid)
{
	struct batadv_tt_global_entry *tt;
	bool ret;

	tt = batadv_tt_global_hash_find(bat_priv, addr, vid);
	if (!tt)
		return false;

	ret = tt->common.flags & BATADV_TT_CLIENT_ISOLA;

	batadv_tt_global_entry_free_ref(tt);

	return ret;
}