summaryrefslogtreecommitdiff
path: root/source4/dsdb/samdb/ldb_modules/repl_meta_data.c
blob: 6ae8e928b0ec4dc0441536adc82a19a7e162ebff (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
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
/*
   ldb database library

   Copyright (C) Simo Sorce  2004-2008
   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005
   Copyright (C) Andrew Tridgell 2005
   Copyright (C) Stefan Metzmacher <metze@samba.org> 2007
   Copyright (C) Matthieu Patou <mat@samba.org> 2010

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

/*
 *  Name: ldb
 *
 *  Component: ldb repl_meta_data module
 *
 *  Description: - add a unique objectGUID onto every new record,
 *               - handle whenCreated, whenChanged timestamps
 *               - handle uSNCreated, uSNChanged numbers
 *               - handle replPropertyMetaData attribute
 *
 *  Author: Simo Sorce
 *  Author: Stefan Metzmacher
 */

#include "includes.h"
#include "ldb_module.h"
#include "dsdb/samdb/samdb.h"
#include "dsdb/common/proto.h"
#include "../libds/common/flags.h"
#include "librpc/gen_ndr/ndr_misc.h"
#include "librpc/gen_ndr/ndr_drsuapi.h"
#include "librpc/gen_ndr/ndr_drsblobs.h"
#include "param/param.h"
#include "libcli/security/dom_sid.h"
#include "lib/util/dlinklist.h"
#include "dsdb/samdb/ldb_modules/util.h"
#include "lib/util/binsearch.h"
#include "libcli/security/security.h"
#include "lib/util/tsort.h"

struct replmd_private {
	TALLOC_CTX *la_ctx;
	struct la_entry *la_list;
	TALLOC_CTX *bl_ctx;
	struct la_backlink *la_backlinks;
	struct nc_entry {
		struct nc_entry *prev, *next;
		struct ldb_dn *dn;
		uint64_t mod_usn;
		uint64_t mod_usn_urgent;
	} *ncs;
};

struct la_entry {
	struct la_entry *next, *prev;
	struct drsuapi_DsReplicaLinkedAttribute *la;
};

struct replmd_replicated_request {
	struct ldb_module *module;
	struct ldb_request *req;

	const struct dsdb_schema *schema;

	/* the controls we pass down */
	struct ldb_control **controls;

	/* details for the mode where we apply a bunch of inbound replication meessages */
	bool apply_mode;
	uint32_t index_current;
	struct dsdb_extended_replicated_objects *objs;

	struct ldb_message *search_msg;

	uint64_t seq_num;
	bool is_urgent;
};

enum urgent_situation {
	REPL_URGENT_ON_CREATE = 1,
	REPL_URGENT_ON_UPDATE = 2,
	REPL_URGENT_ON_DELETE = 4
};


static const struct {
	const char *update_name;
	enum urgent_situation repl_situation;
} urgent_objects[] = {
		{"nTDSDSA", (REPL_URGENT_ON_CREATE | REPL_URGENT_ON_DELETE)},
		{"crossRef", (REPL_URGENT_ON_CREATE | REPL_URGENT_ON_DELETE)},
		{"attributeSchema", (REPL_URGENT_ON_CREATE | REPL_URGENT_ON_UPDATE)},
		{"classSchema", (REPL_URGENT_ON_CREATE | REPL_URGENT_ON_UPDATE)},
		{"secret", (REPL_URGENT_ON_CREATE | REPL_URGENT_ON_UPDATE)},
		{"rIDManager", (REPL_URGENT_ON_CREATE | REPL_URGENT_ON_UPDATE)},
		{NULL, 0}
};

/* Attributes looked for when updating or deleting, to check for a urgent replication needed */
static const char *urgent_attrs[] = {
		"lockoutTime",
		"pwdLastSet",
		"userAccountControl",
		NULL
};


static bool replmd_check_urgent_objectclass(const struct ldb_message_element *objectclass_el,
					enum urgent_situation situation)
{
	unsigned int i, j;
	for (i=0; urgent_objects[i].update_name; i++) {

		if ((situation & urgent_objects[i].repl_situation) == 0) {
			continue;
		}

		for (j=0; j<objectclass_el->num_values; j++) {
			const struct ldb_val *v = &objectclass_el->values[j];
			if (ldb_attr_cmp((const char *)v->data, urgent_objects[i].update_name) == 0) {
				return true;
			}
		}
	}
	return false;
}

static bool replmd_check_urgent_attribute(const struct ldb_message_element *el)
{
	if (ldb_attr_in_list(urgent_attrs, el->name)) {
		return true;
	}
	return false;
}


static int replmd_replicated_apply_next(struct replmd_replicated_request *ar);

/*
  initialise the module
  allocate the private structure and build the list
  of partition DNs for use by replmd_notify()
 */
static int replmd_init(struct ldb_module *module)
{
	struct replmd_private *replmd_private;
	struct ldb_context *ldb = ldb_module_get_ctx(module);

	replmd_private = talloc_zero(module, struct replmd_private);
	if (replmd_private == NULL) {
		ldb_oom(ldb);
		return LDB_ERR_OPERATIONS_ERROR;
	}
	ldb_module_set_private(module, replmd_private);

	return ldb_next_init(module);
}

/*
  cleanup our per-transaction contexts
 */
static void replmd_txn_cleanup(struct replmd_private *replmd_private)
{
	talloc_free(replmd_private->la_ctx);
	replmd_private->la_list = NULL;
	replmd_private->la_ctx = NULL;

	talloc_free(replmd_private->bl_ctx);
	replmd_private->la_backlinks = NULL;
	replmd_private->bl_ctx = NULL;
}


struct la_backlink {
	struct la_backlink *next, *prev;
	const char *attr_name;
	struct GUID forward_guid, target_guid;
	bool active;
};

/*
  process a backlinks we accumulated during a transaction, adding and
  deleting the backlinks from the target objects
 */
static int replmd_process_backlink(struct ldb_module *module, struct la_backlink *bl)
{
	struct ldb_dn *target_dn, *source_dn;
	int ret;
	struct ldb_context *ldb = ldb_module_get_ctx(module);
	struct ldb_message *msg;
	TALLOC_CTX *tmp_ctx = talloc_new(bl);
	char *dn_string;

	/*
	  - find DN of target
	  - find DN of source
	  - construct ldb_message
              - either an add or a delete
	 */
	ret = dsdb_module_dn_by_guid(module, tmp_ctx, &bl->target_guid, &target_dn);
	if (ret != LDB_SUCCESS) {
		DEBUG(2,(__location__ ": WARNING: Failed to find target DN for linked attribute with GUID %s\n",
			 GUID_string(bl, &bl->target_guid)));
		return LDB_SUCCESS;
	}

	ret = dsdb_module_dn_by_guid(module, tmp_ctx, &bl->forward_guid, &source_dn);
	if (ret != LDB_SUCCESS) {
		ldb_asprintf_errstring(ldb, "Failed to find source DN for linked attribute with GUID %s\n",
				       GUID_string(bl, &bl->forward_guid));
		talloc_free(tmp_ctx);
		return ret;
	}

	msg = ldb_msg_new(tmp_ctx);
	if (msg == NULL) {
		ldb_module_oom(module);
		talloc_free(tmp_ctx);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	/* construct a ldb_message for adding/deleting the backlink */
	msg->dn = target_dn;
	dn_string = ldb_dn_get_extended_linearized(tmp_ctx, source_dn, 1);
	if (!dn_string) {
		ldb_module_oom(module);
		talloc_free(tmp_ctx);
		return LDB_ERR_OPERATIONS_ERROR;
	}
	ret = ldb_msg_add_steal_string(msg, bl->attr_name, dn_string);
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}
	msg->elements[0].flags = bl->active?LDB_FLAG_MOD_ADD:LDB_FLAG_MOD_DELETE;

	ret = dsdb_module_modify(module, msg, DSDB_FLAG_NEXT_MODULE);
	if (ret != LDB_SUCCESS) {
		ldb_asprintf_errstring(ldb, "Failed to %s backlink from %s to %s - %s",
				       bl->active?"add":"remove",
				       ldb_dn_get_linearized(source_dn),
				       ldb_dn_get_linearized(target_dn),
				       ldb_errstring(ldb));
		talloc_free(tmp_ctx);
		return ret;
	}
	talloc_free(tmp_ctx);
	return ret;
}

/*
  add a backlink to the list of backlinks to add/delete in the prepare
  commit
 */
static int replmd_add_backlink(struct ldb_module *module, const struct dsdb_schema *schema,
			       struct GUID *forward_guid, struct GUID *target_guid,
			       bool active, const struct dsdb_attribute *schema_attr, bool immediate)
{
	const struct dsdb_attribute *target_attr;
	struct la_backlink *bl;
	struct replmd_private *replmd_private =
		talloc_get_type_abort(ldb_module_get_private(module), struct replmd_private);

	target_attr = dsdb_attribute_by_linkID(schema, schema_attr->linkID ^ 1);
	if (!target_attr) {
		/*
		 * windows 2003 has a broken schema where the
		 * definition of msDS-IsDomainFor is missing (which is
		 * supposed to be the backlink of the
		 * msDS-HasDomainNCs attribute
		 */
		return LDB_SUCCESS;
	}

	/* see if its already in the list */
	for (bl=replmd_private->la_backlinks; bl; bl=bl->next) {
		if (GUID_equal(forward_guid, &bl->forward_guid) &&
		    GUID_equal(target_guid, &bl->target_guid) &&
		    (target_attr->lDAPDisplayName == bl->attr_name ||
		     strcmp(target_attr->lDAPDisplayName, bl->attr_name) == 0)) {
			break;
		}
	}

	if (bl) {
		/* we found an existing one */
		if (bl->active == active) {
			return LDB_SUCCESS;
		}
		DLIST_REMOVE(replmd_private->la_backlinks, bl);
		talloc_free(bl);
		return LDB_SUCCESS;
	}

	if (replmd_private->bl_ctx == NULL) {
		replmd_private->bl_ctx = talloc_new(replmd_private);
		if (replmd_private->bl_ctx == NULL) {
			ldb_module_oom(module);
			return LDB_ERR_OPERATIONS_ERROR;
		}
	}

	/* its a new one */
	bl = talloc(replmd_private->bl_ctx, struct la_backlink);
	if (bl == NULL) {
		ldb_module_oom(module);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	/* Ensure the schema does not go away before the bl->attr_name is used */
	if (!talloc_reference(bl, schema)) {
		talloc_free(bl);
		ldb_module_oom(module);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	bl->attr_name = target_attr->lDAPDisplayName;
	bl->forward_guid = *forward_guid;
	bl->target_guid = *target_guid;
	bl->active = active;

	/* the caller may ask for this backlink to be processed
	   immediately */
	if (immediate) {
		int ret = replmd_process_backlink(module, bl);
		talloc_free(bl);
		return ret;
	}

	DLIST_ADD(replmd_private->la_backlinks, bl);

	return LDB_SUCCESS;
}


/*
 * Callback for most write operations in this module:
 *
 * notify the repl task that a object has changed. The notifies are
 * gathered up in the replmd_private structure then written to the
 * @REPLCHANGED object in each partition during the prepare_commit
 */
static int replmd_op_callback(struct ldb_request *req, struct ldb_reply *ares)
{
	int ret;
	struct replmd_replicated_request *ac =
		talloc_get_type_abort(req->context, struct replmd_replicated_request);
	struct replmd_private *replmd_private =
		talloc_get_type_abort(ldb_module_get_private(ac->module), struct replmd_private);
	struct nc_entry *modified_partition;
	struct ldb_control *partition_ctrl;
	const struct dsdb_control_current_partition *partition;

	struct ldb_control **controls;

	partition_ctrl = ldb_reply_get_control(ares, DSDB_CONTROL_CURRENT_PARTITION_OID);

	/* Remove the 'partition' control from what we pass up the chain */
	controls = controls_except_specified(ares->controls, ares, partition_ctrl);

	if (ares->error != LDB_SUCCESS) {
		return ldb_module_done(ac->req, controls,
					ares->response, ares->error);
	}

	if (ares->type != LDB_REPLY_DONE) {
		ldb_set_errstring(ldb_module_get_ctx(ac->module), "Invalid reply type for notify\n!");
		return ldb_module_done(ac->req, NULL,
				       NULL, LDB_ERR_OPERATIONS_ERROR);
	}

	if (!partition_ctrl) {
		ldb_set_errstring(ldb_module_get_ctx(ac->module),"No partition control on reply");
		return ldb_module_done(ac->req, NULL,
				       NULL, LDB_ERR_OPERATIONS_ERROR);
	}

	partition = talloc_get_type_abort(partition_ctrl->data,
				    struct dsdb_control_current_partition);

	if (ac->seq_num > 0) {
		for (modified_partition = replmd_private->ncs; modified_partition;
		     modified_partition = modified_partition->next) {
			if (ldb_dn_compare(modified_partition->dn, partition->dn) == 0) {
				break;
			}
		}

		if (modified_partition == NULL) {
			modified_partition = talloc_zero(replmd_private, struct nc_entry);
			if (!modified_partition) {
				ldb_oom(ldb_module_get_ctx(ac->module));
				return ldb_module_done(ac->req, NULL,
						       NULL, LDB_ERR_OPERATIONS_ERROR);
			}
			modified_partition->dn = ldb_dn_copy(modified_partition, partition->dn);
			if (!modified_partition->dn) {
				ldb_oom(ldb_module_get_ctx(ac->module));
				return ldb_module_done(ac->req, NULL,
						       NULL, LDB_ERR_OPERATIONS_ERROR);
			}
			DLIST_ADD(replmd_private->ncs, modified_partition);
		}

		if (ac->seq_num > modified_partition->mod_usn) {
			modified_partition->mod_usn = ac->seq_num;
			if (ac->is_urgent) {
				modified_partition->mod_usn_urgent = ac->seq_num;
			}
		}
	}

	if (ac->apply_mode) {
		talloc_free(ares);
		ac->index_current++;

		ret = replmd_replicated_apply_next(ac);
		if (ret != LDB_SUCCESS) {
			return ldb_module_done(ac->req, NULL, NULL, ret);
		}
		return ret;
	} else {
		/* free the partition control container here, for the
		 * common path.  Other cases will have it cleaned up
		 * eventually with the ares */
		talloc_free(partition_ctrl);
		return ldb_module_done(ac->req,
				       controls_except_specified(controls, ares, partition_ctrl),
				       ares->response, LDB_SUCCESS);
	}
}


/*
 * update a @REPLCHANGED record in each partition if there have been
 * any writes of replicated data in the partition
 */
static int replmd_notify_store(struct ldb_module *module)
{
	struct replmd_private *replmd_private =
		talloc_get_type(ldb_module_get_private(module), struct replmd_private);

	while (replmd_private->ncs) {
		int ret;
		struct nc_entry *modified_partition = replmd_private->ncs;

		ret = dsdb_module_save_partition_usn(module, modified_partition->dn,
						     modified_partition->mod_usn,
						     modified_partition->mod_usn_urgent);
		if (ret != LDB_SUCCESS) {
			DEBUG(0,(__location__ ": Failed to save partition uSN for %s\n",
				 ldb_dn_get_linearized(modified_partition->dn)));
			return ret;
		}
		DLIST_REMOVE(replmd_private->ncs, modified_partition);
		talloc_free(modified_partition);
	}

	return LDB_SUCCESS;
}


/*
  created a replmd_replicated_request context
 */
static struct replmd_replicated_request *replmd_ctx_init(struct ldb_module *module,
							 struct ldb_request *req)
{
	struct ldb_context *ldb;
	struct replmd_replicated_request *ac;

	ldb = ldb_module_get_ctx(module);

	ac = talloc_zero(req, struct replmd_replicated_request);
	if (ac == NULL) {
		ldb_oom(ldb);
		return NULL;
	}

	ac->module = module;
	ac->req	= req;

	ac->schema = dsdb_get_schema(ldb, ac);
	if (!ac->schema) {
		ldb_debug_set(ldb, LDB_DEBUG_FATAL,
			      "replmd_modify: no dsdb_schema loaded");
		DEBUG(0,(__location__ ": %s\n", ldb_errstring(ldb)));
		return NULL;
	}

	return ac;
}

/*
  add a time element to a record
*/
static int add_time_element(struct ldb_message *msg, const char *attr, time_t t)
{
	struct ldb_message_element *el;
	char *s;

	if (ldb_msg_find_element(msg, attr) != NULL) {
		return LDB_SUCCESS;
	}

	s = ldb_timestring(msg, t);
	if (s == NULL) {
		return LDB_ERR_OPERATIONS_ERROR;
	}

	if (ldb_msg_add_string(msg, attr, s) != LDB_SUCCESS) {
		return LDB_ERR_OPERATIONS_ERROR;
	}

	el = ldb_msg_find_element(msg, attr);
	/* always set as replace. This works because on add ops, the flag
	   is ignored */
	el->flags = LDB_FLAG_MOD_REPLACE;

	return LDB_SUCCESS;
}

/*
  add a uint64_t element to a record
*/
static int add_uint64_element(struct ldb_message *msg, const char *attr, uint64_t v)
{
	struct ldb_message_element *el;

	if (ldb_msg_find_element(msg, attr) != NULL) {
		return LDB_SUCCESS;
	}

	if (ldb_msg_add_fmt(msg, attr, "%llu", (unsigned long long)v) != LDB_SUCCESS) {
		return LDB_ERR_OPERATIONS_ERROR;
	}

	el = ldb_msg_find_element(msg, attr);
	/* always set as replace. This works because on add ops, the flag
	   is ignored */
	el->flags = LDB_FLAG_MOD_REPLACE;

	return LDB_SUCCESS;
}

static int replmd_replPropertyMetaData1_attid_sort(const struct replPropertyMetaData1 *m1,
						   const struct replPropertyMetaData1 *m2,
						   const uint32_t *rdn_attid)
{
	if (m1->attid == m2->attid) {
		return 0;
	}

	/*
	 * the rdn attribute should be at the end!
	 * so we need to return a value greater than zero
	 * which means m1 is greater than m2
	 */
	if (m1->attid == *rdn_attid) {
		return 1;
	}

	/*
	 * the rdn attribute should be at the end!
	 * so we need to return a value less than zero
	 * which means m2 is greater than m1
	 */
	if (m2->attid == *rdn_attid) {
		return -1;
	}

	return m1->attid > m2->attid ? 1 : -1;
}

static int replmd_replPropertyMetaDataCtr1_sort(struct replPropertyMetaDataCtr1 *ctr1,
						const struct dsdb_schema *schema,
						struct ldb_dn *dn)
{
	const char *rdn_name;
	const struct dsdb_attribute *rdn_sa;

	rdn_name = ldb_dn_get_rdn_name(dn);
	if (!rdn_name) {
		DEBUG(0,(__location__ ": No rDN for %s?\n", ldb_dn_get_linearized(dn)));
		return LDB_ERR_OPERATIONS_ERROR;
	}

	rdn_sa = dsdb_attribute_by_lDAPDisplayName(schema, rdn_name);
	if (rdn_sa == NULL) {
		DEBUG(0,(__location__ ": No sa found for rDN %s for %s\n", rdn_name, ldb_dn_get_linearized(dn)));
		return LDB_ERR_OPERATIONS_ERROR;
	}

	DEBUG(6,("Sorting rpmd with attid exception %u rDN=%s DN=%s\n",
		 rdn_sa->attributeID_id, rdn_name, ldb_dn_get_linearized(dn)));

	LDB_TYPESAFE_QSORT(ctr1->array, ctr1->count, &rdn_sa->attributeID_id, replmd_replPropertyMetaData1_attid_sort);

	return LDB_SUCCESS;
}

static int replmd_ldb_message_element_attid_sort(const struct ldb_message_element *e1,
						 const struct ldb_message_element *e2,
						 const struct dsdb_schema *schema)
{
	const struct dsdb_attribute *a1;
	const struct dsdb_attribute *a2;

	/*
	 * TODO: make this faster by caching the dsdb_attribute pointer
	 *       on the ldb_messag_element
	 */

	a1 = dsdb_attribute_by_lDAPDisplayName(schema, e1->name);
	a2 = dsdb_attribute_by_lDAPDisplayName(schema, e2->name);

	/*
	 * TODO: remove this check, we should rely on e1 and e2 having valid attribute names
	 *       in the schema
	 */
	if (!a1 || !a2) {
		return strcasecmp(e1->name, e2->name);
	}
	if (a1->attributeID_id == a2->attributeID_id) {
		return 0;
	}
	return a1->attributeID_id > a2->attributeID_id ? 1 : -1;
}

static void replmd_ldb_message_sort(struct ldb_message *msg,
				    const struct dsdb_schema *schema)
{
	LDB_TYPESAFE_QSORT(msg->elements, msg->num_elements, schema, replmd_ldb_message_element_attid_sort);
}

static int replmd_build_la_val(TALLOC_CTX *mem_ctx, struct ldb_val *v, struct dsdb_dn *dsdb_dn,
			       const struct GUID *invocation_id, uint64_t seq_num,
			       uint64_t local_usn, NTTIME nttime, uint32_t version, bool deleted);


/*
  fix up linked attributes in replmd_add.
  This involves setting up the right meta-data in extended DN
  components, and creating backlinks to the object
 */
static int replmd_add_fix_la(struct ldb_module *module, struct ldb_message_element *el,
			     uint64_t seq_num, const struct GUID *invocationId, time_t t,
			     struct GUID *guid, const struct dsdb_attribute *sa)
{
	unsigned int i;
	TALLOC_CTX *tmp_ctx = talloc_new(el->values);
	struct ldb_context *ldb = ldb_module_get_ctx(module);

	/* We will take a reference to the schema in replmd_add_backlink */
	const struct dsdb_schema *schema = dsdb_get_schema(ldb, NULL);
	NTTIME now;

	unix_to_nt_time(&now, t);

	for (i=0; i<el->num_values; i++) {
		struct ldb_val *v = &el->values[i];
		struct dsdb_dn *dsdb_dn = dsdb_dn_parse(tmp_ctx, ldb, v, sa->syntax->ldap_oid);
		struct GUID target_guid;
		NTSTATUS status;
		int ret;

		/* note that the DN already has the extended
		   components from the extended_dn_store module */
		status = dsdb_get_extended_dn_guid(dsdb_dn->dn, &target_guid, "GUID");
		if (!NT_STATUS_IS_OK(status) || GUID_all_zero(&target_guid)) {
			ret = dsdb_module_guid_by_dn(module, dsdb_dn->dn, &target_guid);
			if (ret != LDB_SUCCESS) {
				talloc_free(tmp_ctx);
				return ret;
			}
			ret = dsdb_set_extended_dn_guid(dsdb_dn->dn, &target_guid, "GUID");
			if (ret != LDB_SUCCESS) {
				talloc_free(tmp_ctx);
				return ret;
			}
		}

		ret = replmd_build_la_val(el->values, v, dsdb_dn, invocationId,
					  seq_num, seq_num, now, 0, false);
		if (ret != LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			return ret;
		}

		ret = replmd_add_backlink(module, schema, guid, &target_guid, true, sa, false);
		if (ret != LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			return ret;
		}
	}

	talloc_free(tmp_ctx);
	return LDB_SUCCESS;
}


/*
  intercept add requests
 */
static int replmd_add(struct ldb_module *module, struct ldb_request *req)
{
	struct ldb_context *ldb;
        struct ldb_control *control;
	struct replmd_replicated_request *ac;
	enum ndr_err_code ndr_err;
	struct ldb_request *down_req;
	struct ldb_message *msg;
        const DATA_BLOB *guid_blob;
	struct GUID guid;
	struct replPropertyMetaDataBlob nmd;
	struct ldb_val nmd_value;
	const struct GUID *our_invocation_id;
	time_t t = time(NULL);
	NTTIME now;
	char *time_str;
	int ret;
	unsigned int i;
	unsigned int functional_level;
	uint32_t ni=0;
	bool allow_add_guid = false;
	bool remove_current_guid = false;
	bool is_urgent = false;
	struct ldb_message_element *objectclass_el;

        /* check if there's a show relax control (used by provision to say 'I know what I'm doing') */
        control = ldb_request_get_control(req, LDB_CONTROL_RELAX_OID);
	if (control) {
		allow_add_guid = true;
	}

	/* do not manipulate our control entries */
	if (ldb_dn_is_special(req->op.add.message->dn)) {
		return ldb_next_request(module, req);
	}

	ldb = ldb_module_get_ctx(module);

	functional_level = dsdb_functional_level(ldb);

	ldb_debug(ldb, LDB_DEBUG_TRACE, "replmd_add\n");

	ac = replmd_ctx_init(module, req);
	if (!ac) {
		return LDB_ERR_OPERATIONS_ERROR;
	}

        guid_blob = ldb_msg_find_ldb_val(req->op.add.message, "objectGUID");
	if ( guid_blob != NULL ) {
		if( !allow_add_guid ) {
			ldb_debug_set(ldb, LDB_DEBUG_ERROR,
			      "replmd_add: it's not allowed to add an object with objectGUID\n");
			talloc_free(ac);
			return LDB_ERR_UNWILLING_TO_PERFORM;
		} else {
			NTSTATUS status = GUID_from_data_blob(guid_blob,&guid);
		        if ( !NT_STATUS_IS_OK(status)) {
       				ldb_debug_set(ldb, LDB_DEBUG_ERROR,
				      "replmd_add: Unable to parse as a GUID the attribute objectGUID\n");
				talloc_free(ac);
				return LDB_ERR_UNWILLING_TO_PERFORM;
			}
			/* we remove this attribute as it can be a string and will not be treated
			correctly and then we will readd it latter on in the good format*/
			remove_current_guid = true;
		}
	} else {
		/* a new GUID */
		guid = GUID_random();
	}

	/* Get a sequence number from the backend */
	ret = ldb_sequence_number(ldb, LDB_SEQ_NEXT, &ac->seq_num);
	if (ret != LDB_SUCCESS) {
		talloc_free(ac);
		return ret;
	}

	/* get our invocationId */
	our_invocation_id = samdb_ntds_invocation_id(ldb);
	if (!our_invocation_id) {
		ldb_debug_set(ldb, LDB_DEBUG_ERROR,
			      "replmd_add: unable to find invocationId\n");
		talloc_free(ac);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	/* we have to copy the message as the caller might have it as a const */
	msg = ldb_msg_copy_shallow(ac, req->op.add.message);
	if (msg == NULL) {
		ldb_oom(ldb);
		talloc_free(ac);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	/* generated times */
	unix_to_nt_time(&now, t);
	time_str = ldb_timestring(msg, t);
	if (!time_str) {
		ldb_oom(ldb);
		talloc_free(ac);
		return LDB_ERR_OPERATIONS_ERROR;
	}
	if (remove_current_guid) {
		ldb_msg_remove_attr(msg,"objectGUID");
	}

	/*
	 * remove autogenerated attributes
	 */
	ldb_msg_remove_attr(msg, "whenCreated");
	ldb_msg_remove_attr(msg, "whenChanged");
	ldb_msg_remove_attr(msg, "uSNCreated");
	ldb_msg_remove_attr(msg, "uSNChanged");
	ldb_msg_remove_attr(msg, "replPropertyMetaData");

	/*
	 * readd replicated attributes
	 */
	ret = ldb_msg_add_string(msg, "whenCreated", time_str);
	if (ret != LDB_SUCCESS) {
		ldb_oom(ldb);
		talloc_free(ac);
		return ret;
	}

	/* build the replication meta_data */
	ZERO_STRUCT(nmd);
	nmd.version		= 1;
	nmd.ctr.ctr1.count	= msg->num_elements;
	nmd.ctr.ctr1.array	= talloc_array(msg,
					       struct replPropertyMetaData1,
					       nmd.ctr.ctr1.count);
	if (!nmd.ctr.ctr1.array) {
		ldb_oom(ldb);
		talloc_free(ac);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	for (i=0; i < msg->num_elements; i++) {
		struct ldb_message_element *e = &msg->elements[i];
		struct replPropertyMetaData1 *m = &nmd.ctr.ctr1.array[ni];
		const struct dsdb_attribute *sa;

		if (e->name[0] == '@') continue;

		sa = dsdb_attribute_by_lDAPDisplayName(ac->schema, e->name);
		if (!sa) {
			ldb_debug_set(ldb, LDB_DEBUG_ERROR,
				      "replmd_add: attribute '%s' not defined in schema\n",
				      e->name);
			talloc_free(ac);
			return LDB_ERR_NO_SUCH_ATTRIBUTE;
		}

		if ((sa->systemFlags & DS_FLAG_ATTR_NOT_REPLICATED) || (sa->systemFlags & DS_FLAG_ATTR_IS_CONSTRUCTED)) {
			/* if the attribute is not replicated (0x00000001)
			 * or constructed (0x00000004) it has no metadata
			 */
			continue;
		}

		if (sa->linkID != 0 && functional_level > DS_DOMAIN_FUNCTION_2000) {
			ret = replmd_add_fix_la(module, e, ac->seq_num, our_invocation_id, t, &guid, sa);
			if (ret != LDB_SUCCESS) {
				talloc_free(ac);
				return ret;
			}
			/* linked attributes are not stored in
			   replPropertyMetaData in FL above w2k */
			continue;
		}

		m->attid			= sa->attributeID_id;
		m->version			= 1;
		m->originating_change_time	= now;
		m->originating_invocation_id	= *our_invocation_id;
		m->originating_usn		= ac->seq_num;
		m->local_usn			= ac->seq_num;
		ni++;
	}

	/* fix meta data count */
	nmd.ctr.ctr1.count = ni;

	/*
	 * sort meta data array, and move the rdn attribute entry to the end
	 */
	ret = replmd_replPropertyMetaDataCtr1_sort(&nmd.ctr.ctr1, ac->schema, msg->dn);
	if (ret != LDB_SUCCESS) {
		talloc_free(ac);
		return ret;
	}

	/* generated NDR encoded values */
	ndr_err = ndr_push_struct_blob(&nmd_value, msg,
				       &nmd,
				       (ndr_push_flags_fn_t)ndr_push_replPropertyMetaDataBlob);
	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
		ldb_oom(ldb);
		talloc_free(ac);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	/*
	 * add the autogenerated values
	 */
	ret = dsdb_msg_add_guid(msg, &guid, "objectGUID");
	if (ret != LDB_SUCCESS) {
		ldb_oom(ldb);
		talloc_free(ac);
		return ret;
	}
	ret = ldb_msg_add_string(msg, "whenChanged", time_str);
	if (ret != LDB_SUCCESS) {
		ldb_oom(ldb);
		talloc_free(ac);
		return ret;
	}
	ret = samdb_msg_add_uint64(ldb, msg, msg, "uSNCreated", ac->seq_num);
	if (ret != LDB_SUCCESS) {
		ldb_oom(ldb);
		talloc_free(ac);
		return ret;
	}
	ret = samdb_msg_add_uint64(ldb, msg, msg, "uSNChanged", ac->seq_num);
	if (ret != LDB_SUCCESS) {
		ldb_oom(ldb);
		talloc_free(ac);
		return ret;
	}
	ret = ldb_msg_add_value(msg, "replPropertyMetaData", &nmd_value, NULL);
	if (ret != LDB_SUCCESS) {
		ldb_oom(ldb);
		talloc_free(ac);
		return ret;
	}

	/*
	 * sort the attributes by attid before storing the object
	 */
	replmd_ldb_message_sort(msg, ac->schema);

	objectclass_el = ldb_msg_find_element(msg, "objectClass");
	is_urgent = replmd_check_urgent_objectclass(objectclass_el,
							REPL_URGENT_ON_CREATE);

	ac->is_urgent = is_urgent;
	ret = ldb_build_add_req(&down_req, ldb, ac,
				msg,
				req->controls,
				ac, replmd_op_callback,
				req);

	if (ret != LDB_SUCCESS) {
		talloc_free(ac);
		return ret;
	}

	if (functional_level == DS_DOMAIN_FUNCTION_2000) {
		ret = ldb_request_add_control(down_req, DSDB_CONTROL_APPLY_LINKS, false, NULL);
		if (ret != LDB_SUCCESS) {
			talloc_free(ac);
			return ret;
		}
	}

	/* mark the control done */
	if (control) {
		control->critical = 0;
	}

	/* go on with the call chain */
	return ldb_next_request(module, down_req);
}


/*
 * update the replPropertyMetaData for one element
 */
static int replmd_update_rpmd_element(struct ldb_context *ldb,
				      struct ldb_message *msg,
				      struct ldb_message_element *el,
				      struct ldb_message_element *old_el,
				      struct replPropertyMetaDataBlob *omd,
				      const struct dsdb_schema *schema,
				      uint64_t *seq_num,
				      const struct GUID *our_invocation_id,
				      NTTIME now)
{
	uint32_t i;
	const struct dsdb_attribute *a;
	struct replPropertyMetaData1 *md1;

	a = dsdb_attribute_by_lDAPDisplayName(schema, el->name);
	if (a == NULL) {
		DEBUG(0,(__location__ ": Unable to find attribute %s in schema\n",
			 el->name));
		return LDB_ERR_OPERATIONS_ERROR;
	}

	if ((a->systemFlags & DS_FLAG_ATTR_NOT_REPLICATED) || (a->systemFlags & DS_FLAG_ATTR_IS_CONSTRUCTED)) {
		return LDB_SUCCESS;
	}

	/* if the attribute's value haven't changed then return LDB_SUCCESS	*/
	if (old_el != NULL && ldb_msg_element_compare(el, old_el) == 0) {
		return LDB_SUCCESS;
	}

	for (i=0; i<omd->ctr.ctr1.count; i++) {
		if (a->attributeID_id == omd->ctr.ctr1.array[i].attid) break;
	}

	if (a->linkID != 0 && dsdb_functional_level(ldb) > DS_DOMAIN_FUNCTION_2000) {
		/* linked attributes are not stored in
		   replPropertyMetaData in FL above w2k, but we do
		   raise the seqnum for the object  */
		if (*seq_num == 0 &&
		    ldb_sequence_number(ldb, LDB_SEQ_NEXT, seq_num) != LDB_SUCCESS) {
			return LDB_ERR_OPERATIONS_ERROR;
		}
		return LDB_SUCCESS;
	}

	if (i == omd->ctr.ctr1.count) {
		/* we need to add a new one */
		omd->ctr.ctr1.array = talloc_realloc(msg, omd->ctr.ctr1.array,
						     struct replPropertyMetaData1, omd->ctr.ctr1.count+1);
		if (omd->ctr.ctr1.array == NULL) {
			ldb_oom(ldb);
			return LDB_ERR_OPERATIONS_ERROR;
		}
		omd->ctr.ctr1.count++;
		ZERO_STRUCT(omd->ctr.ctr1.array[i]);
	}

	/* Get a new sequence number from the backend. We only do this
	 * if we have a change that requires a new
	 * replPropertyMetaData element
	 */
	if (*seq_num == 0) {
		int ret = ldb_sequence_number(ldb, LDB_SEQ_NEXT, seq_num);
		if (ret != LDB_SUCCESS) {
			return LDB_ERR_OPERATIONS_ERROR;
		}
	}

	md1 = &omd->ctr.ctr1.array[i];
	md1->version++;
	md1->attid                     = a->attributeID_id;
	md1->originating_change_time   = now;
	md1->originating_invocation_id = *our_invocation_id;
	md1->originating_usn           = *seq_num;
	md1->local_usn                 = *seq_num;

	return LDB_SUCCESS;
}

static uint64_t find_max_local_usn(struct replPropertyMetaDataBlob omd)
{
	uint32_t count = omd.ctr.ctr1.count;
	uint64_t max = 0;
	uint32_t i;
	for (i=0; i < count; i++) {
		struct replPropertyMetaData1 m = omd.ctr.ctr1.array[i];
		if (max < m.local_usn) {
			max = m.local_usn;
		}
	}
	return max;
}

/*
 * update the replPropertyMetaData object each time we modify an
 * object. This is needed for DRS replication, as the merge on the
 * client is based on this object
 */
static int replmd_update_rpmd(struct ldb_module *module,
			      const struct dsdb_schema *schema,
			      struct ldb_request *req,
			      struct ldb_message *msg, uint64_t *seq_num,
			      time_t t,
			      bool *is_urgent)
{
	const struct ldb_val *omd_value;
	enum ndr_err_code ndr_err;
	struct replPropertyMetaDataBlob omd;
	unsigned int i;
	NTTIME now;
	const struct GUID *our_invocation_id;
	int ret;
	const char *attrs[] = { "replPropertyMetaData", "*", NULL };
	const char *attrs2[] = { "uSNChanged", "objectClass", NULL };
	struct ldb_result *res;
	struct ldb_context *ldb;
	struct ldb_message_element *objectclass_el;
	enum urgent_situation situation;
	bool rodc, rmd_is_provided;

	ldb = ldb_module_get_ctx(module);

	our_invocation_id = samdb_ntds_invocation_id(ldb);
	if (!our_invocation_id) {
		/* this happens during an initial vampire while
		   updating the schema */
		DEBUG(5,("No invocationID - skipping replPropertyMetaData update\n"));
		return LDB_SUCCESS;
	}

	unix_to_nt_time(&now, t);

	if (ldb_request_get_control(req, DSDB_CONTROL_CHANGEREPLMETADATA_OID)) {
		rmd_is_provided = true;
	} else {
		rmd_is_provided = false;
	}

	/* if isDeleted is present and is TRUE, then we consider we are deleting,
	 * otherwise we consider we are updating */
	if (ldb_msg_check_string_attribute(msg, "isDeleted", "TRUE")) {
		situation = REPL_URGENT_ON_DELETE;
	} else {
		situation = REPL_URGENT_ON_UPDATE;
	}

	if (rmd_is_provided) {
		/* In this case the change_replmetadata control was supplied */
		/* We check that it's the only attribute that is provided
		 * (it's a rare case so it's better to keep the code simplier)
		 * We also check that the highest local_usn is bigger than
		 * uSNChanged. */
		uint64_t db_seq;
		if( msg->num_elements != 1 ||
			strncmp(msg->elements[0].name,
				"replPropertyMetaData", 20) ) {
			DEBUG(0,(__location__ ": changereplmetada control called without "\
				"a specified replPropertyMetaData attribute or with others\n"));
			return LDB_ERR_OPERATIONS_ERROR;
		}
		if (situation == REPL_URGENT_ON_DELETE) {
			DEBUG(0,(__location__ ": changereplmetada control can't be called when deleting an object\n"));
			return LDB_ERR_OPERATIONS_ERROR;
		}
		omd_value = ldb_msg_find_ldb_val(msg, "replPropertyMetaData");
		if (!omd_value) {
			DEBUG(0,(__location__ ": replPropertyMetaData was not specified for Object %s\n",
				 ldb_dn_get_linearized(msg->dn)));
			return LDB_ERR_OPERATIONS_ERROR;
		}
		ndr_err = ndr_pull_struct_blob(omd_value, msg, &omd,
					       (ndr_pull_flags_fn_t)ndr_pull_replPropertyMetaDataBlob);
		if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
			DEBUG(0,(__location__ ": Failed to parse replPropertyMetaData for %s\n",
				 ldb_dn_get_linearized(msg->dn)));
			return LDB_ERR_OPERATIONS_ERROR;
		}
		*seq_num = find_max_local_usn(omd);

		ret = dsdb_module_search_dn(module, msg, &res, msg->dn, attrs2,
					    DSDB_FLAG_NEXT_MODULE |
					    DSDB_SEARCH_SHOW_DELETED |
					    DSDB_SEARCH_SHOW_EXTENDED_DN |
					    DSDB_SEARCH_SHOW_DN_IN_STORAGE_FORMAT |
					    DSDB_SEARCH_REVEAL_INTERNALS);

		if (ret != LDB_SUCCESS || res->count != 1) {
			DEBUG(0,(__location__ ": Object %s failed to find uSNChanged\n",
				 ldb_dn_get_linearized(msg->dn)));
			return LDB_ERR_OPERATIONS_ERROR;
		}

		objectclass_el = ldb_msg_find_element(res->msgs[0], "objectClass");
		if (is_urgent && replmd_check_urgent_objectclass(objectclass_el,
								situation)) {
			*is_urgent = true;
		}

		db_seq = ldb_msg_find_attr_as_uint64(res->msgs[0], "uSNChanged", 0);
		if (*seq_num <= db_seq) {
			DEBUG(0,(__location__ ": changereplmetada control provided but max(local_usn)"\
					      " is less or equal to uSNChanged (max = %lld uSNChanged = %lld)\n",
				 (long long)*seq_num, (long long)db_seq));
			return LDB_ERR_OPERATIONS_ERROR;
		}

	} else {
		/* search for the existing replPropertyMetaDataBlob. We need
		 * to use REVEAL and ask for DNs in storage format to support
		 * the check for values being the same in
		 * replmd_update_rpmd_element()
		 */
		ret = dsdb_module_search_dn(module, msg, &res, msg->dn, attrs,
					    DSDB_FLAG_NEXT_MODULE |
					    DSDB_SEARCH_SHOW_DELETED |
					    DSDB_SEARCH_SHOW_EXTENDED_DN |
					    DSDB_SEARCH_SHOW_DN_IN_STORAGE_FORMAT |
					    DSDB_SEARCH_REVEAL_INTERNALS);
		if (ret != LDB_SUCCESS || res->count != 1) {
			DEBUG(0,(__location__ ": Object %s failed to find replPropertyMetaData\n",
				 ldb_dn_get_linearized(msg->dn)));
			return LDB_ERR_OPERATIONS_ERROR;
		}

		objectclass_el = ldb_msg_find_element(res->msgs[0], "objectClass");
		if (is_urgent && replmd_check_urgent_objectclass(objectclass_el,
								situation)) {
			*is_urgent = true;
		}

		omd_value = ldb_msg_find_ldb_val(res->msgs[0], "replPropertyMetaData");
		if (!omd_value) {
			DEBUG(0,(__location__ ": Object %s does not have a replPropertyMetaData attribute\n",
				 ldb_dn_get_linearized(msg->dn)));
			return LDB_ERR_OPERATIONS_ERROR;
		}

		ndr_err = ndr_pull_struct_blob(omd_value, msg, &omd,
					       (ndr_pull_flags_fn_t)ndr_pull_replPropertyMetaDataBlob);
		if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
			DEBUG(0,(__location__ ": Failed to parse replPropertyMetaData for %s\n",
				 ldb_dn_get_linearized(msg->dn)));
			return LDB_ERR_OPERATIONS_ERROR;
		}

		if (omd.version != 1) {
			DEBUG(0,(__location__ ": bad version %u in replPropertyMetaData for %s\n",
				 omd.version, ldb_dn_get_linearized(msg->dn)));
			return LDB_ERR_OPERATIONS_ERROR;
		}

		for (i=0; i<msg->num_elements; i++) {
			struct ldb_message_element *old_el;
			old_el = ldb_msg_find_element(res->msgs[0], msg->elements[i].name);
			ret = replmd_update_rpmd_element(ldb, msg, &msg->elements[i], old_el, &omd, schema, seq_num,
							 our_invocation_id, now);
			if (ret != LDB_SUCCESS) {
				return ret;
			}

			if (is_urgent && !*is_urgent && (situation == REPL_URGENT_ON_UPDATE)) {
				*is_urgent = replmd_check_urgent_attribute(&msg->elements[i]);
			}

		}
	}
	/*
	 * replmd_update_rpmd_element has done an update if the
	 * seq_num is set
	 */
	if (*seq_num != 0) {
		struct ldb_val *md_value;
		struct ldb_message_element *el;

		/*if we are RODC and this is a DRSR update then its ok*/
		if (!ldb_request_get_control(req, DSDB_CONTROL_REPLICATED_UPDATE_OID)) {
			ret = samdb_rodc(ldb, &rodc);
			if (ret != LDB_SUCCESS) {
				DEBUG(4, (__location__ ": unable to tell if we are an RODC\n"));
			} else if (rodc) {
				ldb_asprintf_errstring(ldb, "RODC modify is forbidden\n");
				return LDB_ERR_REFERRAL;
			}
		}

		md_value = talloc(msg, struct ldb_val);
		if (md_value == NULL) {
			ldb_oom(ldb);
			return LDB_ERR_OPERATIONS_ERROR;
		}

		ret = replmd_replPropertyMetaDataCtr1_sort(&omd.ctr.ctr1, schema, msg->dn);
		if (ret != LDB_SUCCESS) {
			return ret;
		}

		ndr_err = ndr_push_struct_blob(md_value, msg, &omd,
					       (ndr_push_flags_fn_t)ndr_push_replPropertyMetaDataBlob);
		if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
			DEBUG(0,(__location__ ": Failed to marshall replPropertyMetaData for %s\n",
				 ldb_dn_get_linearized(msg->dn)));
			return LDB_ERR_OPERATIONS_ERROR;
		}

		ret = ldb_msg_add_empty(msg, "replPropertyMetaData", LDB_FLAG_MOD_REPLACE, &el);
		if (ret != LDB_SUCCESS) {
			DEBUG(0,(__location__ ": Failed to add updated replPropertyMetaData %s\n",
				 ldb_dn_get_linearized(msg->dn)));
			return ret;
		}

		el->num_values = 1;
		el->values = md_value;
	}

	return LDB_SUCCESS;
}

struct parsed_dn {
	struct dsdb_dn *dsdb_dn;
	struct GUID *guid;
	struct ldb_val *v;
};

static int parsed_dn_compare(struct parsed_dn *pdn1, struct parsed_dn *pdn2)
{
	return GUID_compare(pdn1->guid, pdn2->guid);
}

static struct parsed_dn *parsed_dn_find(struct parsed_dn *pdn, int count, struct GUID *guid, struct ldb_dn *dn)
{
	struct parsed_dn *ret;
	if (dn && GUID_all_zero(guid)) {
		/* when updating a link using DRS, we sometimes get a
		   NULL GUID. We then need to try and match by DN */
		int i;
		for (i=0; i<count; i++) {
			if (ldb_dn_compare(pdn[i].dsdb_dn->dn, dn) == 0) {
				dsdb_get_extended_dn_guid(pdn[i].dsdb_dn->dn, guid, "GUID");
				return &pdn[i];
			}
		}
		return NULL;
	}
	BINARY_ARRAY_SEARCH(pdn, count, guid, guid, GUID_compare, ret);
	return ret;
}

/*
  get a series of message element values as an array of DNs and GUIDs
  the result is sorted by GUID
 */
static int get_parsed_dns(struct ldb_module *module, TALLOC_CTX *mem_ctx,
			  struct ldb_message_element *el, struct parsed_dn **pdn,
			  const char *ldap_oid)
{
	unsigned int i;
	struct ldb_context *ldb = ldb_module_get_ctx(module);

	if (el == NULL) {
		*pdn = NULL;
		return LDB_SUCCESS;
	}

	(*pdn) = talloc_array(mem_ctx, struct parsed_dn, el->num_values);
	if (!*pdn) {
		ldb_module_oom(module);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	for (i=0; i<el->num_values; i++) {
		struct ldb_val *v = &el->values[i];
		NTSTATUS status;
		struct ldb_dn *dn;
		struct parsed_dn *p;

		p = &(*pdn)[i];

		p->dsdb_dn = dsdb_dn_parse(*pdn, ldb, v, ldap_oid);
		if (p->dsdb_dn == NULL) {
			return LDB_ERR_INVALID_DN_SYNTAX;
		}

		dn = p->dsdb_dn->dn;

		p->guid = talloc(*pdn, struct GUID);
		if (p->guid == NULL) {
			ldb_module_oom(module);
			return LDB_ERR_OPERATIONS_ERROR;
		}

		status = dsdb_get_extended_dn_guid(dn, p->guid, "GUID");
		if (NT_STATUS_EQUAL(status, NT_STATUS_OBJECT_NAME_NOT_FOUND)) {
			/* we got a DN without a GUID - go find the GUID */
			int ret = dsdb_module_guid_by_dn(module, dn, p->guid);
			if (ret != LDB_SUCCESS) {
				ldb_asprintf_errstring(ldb, "Unable to find GUID for DN %s\n",
						       ldb_dn_get_linearized(dn));
				return ret;
			}
			ret = dsdb_set_extended_dn_guid(dn, p->guid, "GUID");
			if (ret != LDB_SUCCESS) {
				return ret;
			}
		} else if (!NT_STATUS_IS_OK(status)) {
			return LDB_ERR_OPERATIONS_ERROR;
		}

		/* keep a pointer to the original ldb_val */
		p->v = v;
	}

	TYPESAFE_QSORT(*pdn, el->num_values, parsed_dn_compare);

	return LDB_SUCCESS;
}

/*
  build a new extended DN, including all meta data fields

  RMD_FLAGS           = DSDB_RMD_FLAG_* bits
  RMD_ADDTIME         = originating_add_time
  RMD_INVOCID         = originating_invocation_id
  RMD_CHANGETIME      = originating_change_time
  RMD_ORIGINATING_USN = originating_usn
  RMD_LOCAL_USN       = local_usn
  RMD_VERSION         = version
 */
static int replmd_build_la_val(TALLOC_CTX *mem_ctx, struct ldb_val *v, struct dsdb_dn *dsdb_dn,
			       const struct GUID *invocation_id, uint64_t seq_num,
			       uint64_t local_usn, NTTIME nttime, uint32_t version, bool deleted)
{
	struct ldb_dn *dn = dsdb_dn->dn;
	const char *tstring, *usn_string, *flags_string;
	struct ldb_val tval;
	struct ldb_val iid;
	struct ldb_val usnv, local_usnv;
	struct ldb_val vers, flagsv;
	NTSTATUS status;
	int ret;
	const char *dnstring;
	char *vstring;
	uint32_t rmd_flags = deleted?DSDB_RMD_FLAG_DELETED:0;

	tstring = talloc_asprintf(mem_ctx, "%llu", (unsigned long long)nttime);
	if (!tstring) {
		return LDB_ERR_OPERATIONS_ERROR;
	}
	tval = data_blob_string_const(tstring);

	usn_string = talloc_asprintf(mem_ctx, "%llu", (unsigned long long)seq_num);
	if (!usn_string) {
		return LDB_ERR_OPERATIONS_ERROR;
	}
	usnv = data_blob_string_const(usn_string);

	usn_string = talloc_asprintf(mem_ctx, "%llu", (unsigned long long)local_usn);
	if (!usn_string) {
		return LDB_ERR_OPERATIONS_ERROR;
	}
	local_usnv = data_blob_string_const(usn_string);

	vstring = talloc_asprintf(mem_ctx, "%lu", (unsigned long)version);
	if (!vstring) {
		return LDB_ERR_OPERATIONS_ERROR;
	}
	vers = data_blob_string_const(vstring);

	status = GUID_to_ndr_blob(invocation_id, dn, &iid);
	if (!NT_STATUS_IS_OK(status)) {
		return LDB_ERR_OPERATIONS_ERROR;
	}

	flags_string = talloc_asprintf(mem_ctx, "%u", rmd_flags);
	if (!flags_string) {
		return LDB_ERR_OPERATIONS_ERROR;
	}
	flagsv = data_blob_string_const(flags_string);

	ret = ldb_dn_set_extended_component(dn, "RMD_FLAGS", &flagsv);
	if (ret != LDB_SUCCESS) return ret;
	ret = ldb_dn_set_extended_component(dn, "RMD_ADDTIME", &tval);
	if (ret != LDB_SUCCESS) return ret;
	ret = ldb_dn_set_extended_component(dn, "RMD_INVOCID", &iid);
	if (ret != LDB_SUCCESS) return ret;
	ret = ldb_dn_set_extended_component(dn, "RMD_CHANGETIME", &tval);
	if (ret != LDB_SUCCESS) return ret;
	ret = ldb_dn_set_extended_component(dn, "RMD_LOCAL_USN", &local_usnv);
	if (ret != LDB_SUCCESS) return ret;
	ret = ldb_dn_set_extended_component(dn, "RMD_ORIGINATING_USN", &usnv);
	if (ret != LDB_SUCCESS) return ret;
	ret = ldb_dn_set_extended_component(dn, "RMD_VERSION", &vers);
	if (ret != LDB_SUCCESS) return ret;

	dnstring = dsdb_dn_get_extended_linearized(mem_ctx, dsdb_dn, 1);
	if (dnstring == NULL) {
		return LDB_ERR_OPERATIONS_ERROR;
	}
	*v = data_blob_string_const(dnstring);

	return LDB_SUCCESS;
}

static int replmd_update_la_val(TALLOC_CTX *mem_ctx, struct ldb_val *v, struct dsdb_dn *dsdb_dn,
				struct dsdb_dn *old_dsdb_dn, const struct GUID *invocation_id,
				uint64_t seq_num, uint64_t local_usn, NTTIME nttime,
				uint32_t version, bool deleted);

/*
  check if any links need upgrading from w2k format

  The parent_ctx is the ldb_message_element which contains the values array that dns[i].v points at, and which should be used for allocating any new value.
 */
static int replmd_check_upgrade_links(struct parsed_dn *dns, uint32_t count, struct ldb_message_element *parent_ctx, const struct GUID *invocation_id)
{
	uint32_t i;
	for (i=0; i<count; i++) {
		NTSTATUS status;
		uint32_t version;
		int ret;

		status = dsdb_get_extended_dn_uint32(dns[i].dsdb_dn->dn, &version, "RMD_VERSION");
		if (!NT_STATUS_EQUAL(status, NT_STATUS_OBJECT_NAME_NOT_FOUND)) {
			continue;
		}

		/* it's an old one that needs upgrading */
		ret = replmd_update_la_val(parent_ctx->values, dns[i].v, dns[i].dsdb_dn, dns[i].dsdb_dn, invocation_id,
					   1, 1, 0, 0, false);
		if (ret != LDB_SUCCESS) {
			return ret;
		}
	}
	return LDB_SUCCESS;
}

/*
  update an extended DN, including all meta data fields

  see replmd_build_la_val for value names
 */
static int replmd_update_la_val(TALLOC_CTX *mem_ctx, struct ldb_val *v, struct dsdb_dn *dsdb_dn,
				struct dsdb_dn *old_dsdb_dn, const struct GUID *invocation_id,
				uint64_t seq_num, uint64_t local_usn, NTTIME nttime,
				uint32_t version, bool deleted)
{
	struct ldb_dn *dn = dsdb_dn->dn;
	const char *tstring, *usn_string, *flags_string;
	struct ldb_val tval;
	struct ldb_val iid;
	struct ldb_val usnv, local_usnv;
	struct ldb_val vers, flagsv;
	const struct ldb_val *old_addtime;
	uint32_t old_version;
	NTSTATUS status;
	int ret;
	const char *dnstring;
	char *vstring;
	uint32_t rmd_flags = deleted?DSDB_RMD_FLAG_DELETED:0;

	tstring = talloc_asprintf(mem_ctx, "%llu", (unsigned long long)nttime);
	if (!tstring) {
		return LDB_ERR_OPERATIONS_ERROR;
	}
	tval = data_blob_string_const(tstring);

	usn_string = talloc_asprintf(mem_ctx, "%llu", (unsigned long long)seq_num);
	if (!usn_string) {
		return LDB_ERR_OPERATIONS_ERROR;
	}
	usnv = data_blob_string_const(usn_string);

	usn_string = talloc_asprintf(mem_ctx, "%llu", (unsigned long long)local_usn);
	if (!usn_string) {
		return LDB_ERR_OPERATIONS_ERROR;
	}
	local_usnv = data_blob_string_const(usn_string);

	status = GUID_to_ndr_blob(invocation_id, dn, &iid);
	if (!NT_STATUS_IS_OK(status)) {
		return LDB_ERR_OPERATIONS_ERROR;
	}

	flags_string = talloc_asprintf(mem_ctx, "%u", rmd_flags);
	if (!flags_string) {
		return LDB_ERR_OPERATIONS_ERROR;
	}
	flagsv = data_blob_string_const(flags_string);

	ret = ldb_dn_set_extended_component(dn, "RMD_FLAGS", &flagsv);
	if (ret != LDB_SUCCESS) return ret;

	/* get the ADDTIME from the original */
	old_addtime = ldb_dn_get_extended_component(old_dsdb_dn->dn, "RMD_ADDTIME");
	if (old_addtime == NULL) {
		old_addtime = &tval;
	}
	if (dsdb_dn != old_dsdb_dn) {
		ret = ldb_dn_set_extended_component(dn, "RMD_ADDTIME", old_addtime);
		if (ret != LDB_SUCCESS) return ret;
	}

	/* use our invocation id */
	ret = ldb_dn_set_extended_component(dn, "RMD_INVOCID", &iid);
	if (ret != LDB_SUCCESS) return ret;

	/* changetime is the current time */
	ret = ldb_dn_set_extended_component(dn, "RMD_CHANGETIME", &tval);
	if (ret != LDB_SUCCESS) return ret;

	/* update the USN */
	ret = ldb_dn_set_extended_component(dn, "RMD_ORIGINATING_USN", &usnv);
	if (ret != LDB_SUCCESS) return ret;

	ret = ldb_dn_set_extended_component(dn, "RMD_LOCAL_USN", &local_usnv);
	if (ret != LDB_SUCCESS) return ret;

	/* increase the version by 1 */
	status = dsdb_get_extended_dn_uint32(old_dsdb_dn->dn, &old_version, "RMD_VERSION");
	if (NT_STATUS_IS_OK(status) && old_version >= version) {
		version = old_version+1;
	}
	vstring = talloc_asprintf(dn, "%lu", (unsigned long)version);
	vers = data_blob_string_const(vstring);
	ret = ldb_dn_set_extended_component(dn, "RMD_VERSION", &vers);
	if (ret != LDB_SUCCESS) return ret;

	dnstring = dsdb_dn_get_extended_linearized(mem_ctx, dsdb_dn, 1);
	if (dnstring == NULL) {
		return LDB_ERR_OPERATIONS_ERROR;
	}
	*v = data_blob_string_const(dnstring);

	return LDB_SUCCESS;
}

/*
  handle adding a linked attribute
 */
static int replmd_modify_la_add(struct ldb_module *module,
				const struct dsdb_schema *schema,
				struct ldb_message *msg,
				struct ldb_message_element *el,
				struct ldb_message_element *old_el,
				const struct dsdb_attribute *schema_attr,
				uint64_t seq_num,
				time_t t,
				struct GUID *msg_guid)
{
	unsigned int i;
	struct parsed_dn *dns, *old_dns;
	TALLOC_CTX *tmp_ctx = talloc_new(msg);
	int ret;
	struct ldb_val *new_values = NULL;
	unsigned int num_new_values = 0;
	unsigned old_num_values = old_el?old_el->num_values:0;
	const struct GUID *invocation_id;
	struct ldb_context *ldb = ldb_module_get_ctx(module);
	NTTIME now;

	unix_to_nt_time(&now, t);

	ret = get_parsed_dns(module, tmp_ctx, el, &dns, schema_attr->syntax->ldap_oid);
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}

	ret = get_parsed_dns(module, tmp_ctx, old_el, &old_dns, schema_attr->syntax->ldap_oid);
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}

	invocation_id = samdb_ntds_invocation_id(ldb);
	if (!invocation_id) {
		talloc_free(tmp_ctx);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	ret = replmd_check_upgrade_links(old_dns, old_num_values, old_el, invocation_id);
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}

	/* for each new value, see if it exists already with the same GUID */
	for (i=0; i<el->num_values; i++) {
		struct parsed_dn *p = parsed_dn_find(old_dns, old_num_values, dns[i].guid, NULL);
		if (p == NULL) {
			/* this is a new linked attribute value */
			new_values = talloc_realloc(tmp_ctx, new_values, struct ldb_val, num_new_values+1);
			if (new_values == NULL) {
				ldb_module_oom(module);
				talloc_free(tmp_ctx);
				return LDB_ERR_OPERATIONS_ERROR;
			}
			ret = replmd_build_la_val(new_values, &new_values[num_new_values], dns[i].dsdb_dn,
						  invocation_id, seq_num, seq_num, now, 0, false);
			if (ret != LDB_SUCCESS) {
				talloc_free(tmp_ctx);
				return ret;
			}
			num_new_values++;
		} else {
			/* this is only allowed if the GUID was
			   previously deleted. */
			uint32_t rmd_flags = dsdb_dn_rmd_flags(p->dsdb_dn->dn);

			if (!(rmd_flags & DSDB_RMD_FLAG_DELETED)) {
				ldb_asprintf_errstring(ldb, "Attribute %s already exists for target GUID %s",
						       el->name, GUID_string(tmp_ctx, p->guid));
				talloc_free(tmp_ctx);
				return LDB_ERR_ATTRIBUTE_OR_VALUE_EXISTS;
			}
			ret = replmd_update_la_val(old_el->values, p->v, dns[i].dsdb_dn, p->dsdb_dn,
						   invocation_id, seq_num, seq_num, now, 0, false);
			if (ret != LDB_SUCCESS) {
				talloc_free(tmp_ctx);
				return ret;
			}
		}

		ret = replmd_add_backlink(module, schema, msg_guid, dns[i].guid, true, schema_attr, true);
		if (ret != LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			return ret;
		}
	}

	/* add the new ones on to the end of the old values, constructing a new el->values */
	el->values = talloc_realloc(msg->elements, old_el?old_el->values:NULL,
				    struct ldb_val,
				    old_num_values+num_new_values);
	if (el->values == NULL) {
		ldb_module_oom(module);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	memcpy(&el->values[old_num_values], new_values, num_new_values*sizeof(struct ldb_val));
	el->num_values = old_num_values + num_new_values;

	talloc_steal(msg->elements, el->values);
	talloc_steal(el->values, new_values);

	talloc_free(tmp_ctx);

	/* we now tell the backend to replace all existing values
	   with the one we have constructed */
	el->flags = LDB_FLAG_MOD_REPLACE;

	return LDB_SUCCESS;
}


/*
  handle deleting all active linked attributes
 */
static int replmd_modify_la_delete(struct ldb_module *module,
				   const struct dsdb_schema *schema,
				   struct ldb_message *msg,
				   struct ldb_message_element *el,
				   struct ldb_message_element *old_el,
				   const struct dsdb_attribute *schema_attr,
				   uint64_t seq_num,
				   time_t t,
				   struct GUID *msg_guid)
{
	unsigned int i;
	struct parsed_dn *dns, *old_dns;
	TALLOC_CTX *tmp_ctx = talloc_new(msg);
	int ret;
	const struct GUID *invocation_id;
	struct ldb_context *ldb = ldb_module_get_ctx(module);
	NTTIME now;

	unix_to_nt_time(&now, t);

	/* check if there is nothing to delete */
	if ((!old_el || old_el->num_values == 0) &&
	    el->num_values == 0) {
		return LDB_SUCCESS;
	}

	if (!old_el || old_el->num_values == 0) {
		return LDB_ERR_NO_SUCH_ATTRIBUTE;
	}

	ret = get_parsed_dns(module, tmp_ctx, el, &dns, schema_attr->syntax->ldap_oid);
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}

	ret = get_parsed_dns(module, tmp_ctx, old_el, &old_dns, schema_attr->syntax->ldap_oid);
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}

	invocation_id = samdb_ntds_invocation_id(ldb);
	if (!invocation_id) {
		return LDB_ERR_OPERATIONS_ERROR;
	}

	ret = replmd_check_upgrade_links(old_dns, old_el->num_values, old_el, invocation_id);
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}

	el->values = NULL;

	/* see if we are being asked to delete any links that
	   don't exist or are already deleted */
	for (i=0; i<el->num_values; i++) {
		struct parsed_dn *p = &dns[i];
		struct parsed_dn *p2;
		uint32_t rmd_flags;

		p2 = parsed_dn_find(old_dns, old_el->num_values, p->guid, NULL);
		if (!p2) {
			ldb_asprintf_errstring(ldb, "Attribute %s doesn't exist for target GUID %s",
					       el->name, GUID_string(tmp_ctx, p->guid));
			return LDB_ERR_NO_SUCH_ATTRIBUTE;
		}
		rmd_flags = dsdb_dn_rmd_flags(p2->dsdb_dn->dn);
		if (rmd_flags & DSDB_RMD_FLAG_DELETED) {
			ldb_asprintf_errstring(ldb, "Attribute %s already deleted for target GUID %s",
					       el->name, GUID_string(tmp_ctx, p->guid));
			return LDB_ERR_NO_SUCH_ATTRIBUTE;
		}
	}

	/* for each new value, see if it exists already with the same GUID
	   if it is not already deleted and matches the delete list then delete it
	*/
	for (i=0; i<old_el->num_values; i++) {
		struct parsed_dn *p = &old_dns[i];
		uint32_t rmd_flags;

		if (el->num_values && parsed_dn_find(dns, el->num_values, p->guid, NULL) == NULL) {
			continue;
		}

		rmd_flags = dsdb_dn_rmd_flags(p->dsdb_dn->dn);
		if (rmd_flags & DSDB_RMD_FLAG_DELETED) continue;

		ret = replmd_update_la_val(old_el->values, p->v, p->dsdb_dn, p->dsdb_dn,
					   invocation_id, seq_num, seq_num, now, 0, true);
		if (ret != LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			return ret;
		}

		ret = replmd_add_backlink(module, schema, msg_guid, old_dns[i].guid, false, schema_attr, true);
		if (ret != LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			return ret;
		}
	}

	el->values = talloc_steal(msg->elements, old_el->values);
	el->num_values = old_el->num_values;

	talloc_free(tmp_ctx);

	/* we now tell the backend to replace all existing values
	   with the one we have constructed */
	el->flags = LDB_FLAG_MOD_REPLACE;

	return LDB_SUCCESS;
}

/*
  handle replacing a linked attribute
 */
static int replmd_modify_la_replace(struct ldb_module *module,
				    const struct dsdb_schema *schema,
				    struct ldb_message *msg,
				    struct ldb_message_element *el,
				    struct ldb_message_element *old_el,
				    const struct dsdb_attribute *schema_attr,
				    uint64_t seq_num,
				    time_t t,
				    struct GUID *msg_guid)
{
	unsigned int i;
	struct parsed_dn *dns, *old_dns;
	TALLOC_CTX *tmp_ctx = talloc_new(msg);
	int ret;
	const struct GUID *invocation_id;
	struct ldb_context *ldb = ldb_module_get_ctx(module);
	struct ldb_val *new_values = NULL;
	unsigned int num_new_values = 0;
	unsigned int old_num_values = old_el?old_el->num_values:0;
	NTTIME now;

	unix_to_nt_time(&now, t);

	/* check if there is nothing to replace */
	if ((!old_el || old_el->num_values == 0) &&
	    el->num_values == 0) {
		return LDB_SUCCESS;
	}

	ret = get_parsed_dns(module, tmp_ctx, el, &dns, schema_attr->syntax->ldap_oid);
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}

	ret = get_parsed_dns(module, tmp_ctx, old_el, &old_dns, schema_attr->syntax->ldap_oid);
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}

	invocation_id = samdb_ntds_invocation_id(ldb);
	if (!invocation_id) {
		return LDB_ERR_OPERATIONS_ERROR;
	}

	ret = replmd_check_upgrade_links(old_dns, old_num_values, old_el, invocation_id);
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}

	/* mark all the old ones as deleted */
	for (i=0; i<old_num_values; i++) {
		struct parsed_dn *old_p = &old_dns[i];
		struct parsed_dn *p;
		uint32_t rmd_flags = dsdb_dn_rmd_flags(old_p->dsdb_dn->dn);

		if (rmd_flags & DSDB_RMD_FLAG_DELETED) continue;

		ret = replmd_add_backlink(module, schema, msg_guid, old_dns[i].guid, false, schema_attr, false);
		if (ret != LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			return ret;
		}

		p = parsed_dn_find(dns, el->num_values, old_p->guid, NULL);
		if (p) {
			/* we don't delete it if we are re-adding it */
			continue;
		}

		ret = replmd_update_la_val(old_el->values, old_p->v, old_p->dsdb_dn, old_p->dsdb_dn,
					   invocation_id, seq_num, seq_num, now, 0, true);
		if (ret != LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			return ret;
		}
	}

	/* for each new value, either update its meta-data, or add it
	 * to old_el
	*/
	for (i=0; i<el->num_values; i++) {
		struct parsed_dn *p = &dns[i], *old_p;

		if (old_dns &&
		    (old_p = parsed_dn_find(old_dns,
					    old_num_values, p->guid, NULL)) != NULL) {
			/* update in place */
			ret = replmd_update_la_val(old_el->values, old_p->v, old_p->dsdb_dn,
						   old_p->dsdb_dn, invocation_id,
						   seq_num, seq_num, now, 0, false);
			if (ret != LDB_SUCCESS) {
				talloc_free(tmp_ctx);
				return ret;
			}
		} else {
			/* add a new one */
			new_values = talloc_realloc(tmp_ctx, new_values, struct ldb_val,
						    num_new_values+1);
			if (new_values == NULL) {
				ldb_module_oom(module);
				talloc_free(tmp_ctx);
				return LDB_ERR_OPERATIONS_ERROR;
			}
			ret = replmd_build_la_val(new_values, &new_values[num_new_values], dns[i].dsdb_dn,
						  invocation_id, seq_num, seq_num, now, 0, false);
			if (ret != LDB_SUCCESS) {
				talloc_free(tmp_ctx);
				return ret;
			}
			num_new_values++;
		}

		ret = replmd_add_backlink(module, schema, msg_guid, dns[i].guid, true, schema_attr, false);
		if (ret != LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			return ret;
		}
	}

	/* add the new values to the end of old_el */
	if (num_new_values != 0) {
		el->values = talloc_realloc(msg->elements, old_el?old_el->values:NULL,
					    struct ldb_val, old_num_values+num_new_values);
		if (el->values == NULL) {
			ldb_module_oom(module);
			return LDB_ERR_OPERATIONS_ERROR;
		}
		memcpy(&el->values[old_num_values], &new_values[0],
		       sizeof(struct ldb_val)*num_new_values);
		el->num_values = old_num_values + num_new_values;
		talloc_steal(msg->elements, new_values);
	} else {
		el->values = old_el->values;
		el->num_values = old_el->num_values;
		talloc_steal(msg->elements, el->values);
	}

	talloc_free(tmp_ctx);

	/* we now tell the backend to replace all existing values
	   with the one we have constructed */
	el->flags = LDB_FLAG_MOD_REPLACE;

	return LDB_SUCCESS;
}


/*
  handle linked attributes in modify requests
 */
static int replmd_modify_handle_linked_attribs(struct ldb_module *module,
					       struct ldb_message *msg,
					       uint64_t seq_num, time_t t)
{
	struct ldb_result *res;
	unsigned int i;
	int ret;
	struct ldb_context *ldb = ldb_module_get_ctx(module);
	struct ldb_message *old_msg;

	const struct dsdb_schema *schema;
	struct GUID old_guid;

	if (seq_num == 0) {
		/* there the replmd_update_rpmd code has already
		 * checked and saw that there are no linked
		 * attributes */
		return LDB_SUCCESS;
	}

	if (dsdb_functional_level(ldb) == DS_DOMAIN_FUNCTION_2000) {
		/* don't do anything special for linked attributes */
		return LDB_SUCCESS;
	}

	ret = dsdb_module_search_dn(module, msg, &res, msg->dn, NULL,
	                            DSDB_FLAG_NEXT_MODULE |
	                            DSDB_SEARCH_SHOW_DELETED |
				    DSDB_SEARCH_REVEAL_INTERNALS |
				    DSDB_SEARCH_SHOW_DN_IN_STORAGE_FORMAT);
	if (ret != LDB_SUCCESS) {
		return ret;
	}
	schema = dsdb_get_schema(ldb, res);
	if (!schema) {
		return LDB_ERR_OPERATIONS_ERROR;
	}

	old_msg = res->msgs[0];

	old_guid = samdb_result_guid(old_msg, "objectGUID");

	for (i=0; i<msg->num_elements; i++) {
		struct ldb_message_element *el = &msg->elements[i];
		struct ldb_message_element *old_el, *new_el;
		const struct dsdb_attribute *schema_attr
			= dsdb_attribute_by_lDAPDisplayName(schema, el->name);
		if (!schema_attr) {
			ldb_asprintf_errstring(ldb,
					       "attribute %s is not a valid attribute in schema", el->name);
			return LDB_ERR_OBJECT_CLASS_VIOLATION;
		}
		if (schema_attr->linkID == 0) {
			continue;
		}
		if ((schema_attr->linkID & 1) == 1) {
			/* Odd is for the target.  Illegal to modify */
			ldb_asprintf_errstring(ldb,
					       "attribute %s must not be modified directly, it is a linked attribute", el->name);
			return LDB_ERR_UNWILLING_TO_PERFORM;
		}
		old_el = ldb_msg_find_element(old_msg, el->name);
		switch (el->flags & LDB_FLAG_MOD_MASK) {
		case LDB_FLAG_MOD_REPLACE:
			ret = replmd_modify_la_replace(module, schema, msg, el, old_el, schema_attr, seq_num, t, &old_guid);
			break;
		case LDB_FLAG_MOD_DELETE:
			ret = replmd_modify_la_delete(module, schema, msg, el, old_el, schema_attr, seq_num, t, &old_guid);
			break;
		case LDB_FLAG_MOD_ADD:
			ret = replmd_modify_la_add(module, schema, msg, el, old_el, schema_attr, seq_num, t, &old_guid);
			break;
		default:
			ldb_asprintf_errstring(ldb,
					       "invalid flags 0x%x for %s linked attribute",
					       el->flags, el->name);
			return LDB_ERR_UNWILLING_TO_PERFORM;
		}
		if (ret != LDB_SUCCESS) {
			return ret;
		}
		if (old_el) {
			ldb_msg_remove_attr(old_msg, el->name);
		}
		ldb_msg_add_empty(old_msg, el->name, 0, &new_el);
		new_el->num_values = el->num_values;
		new_el->values = talloc_steal(msg->elements, el->values);

		/* TODO: this relises a bit too heavily on the exact
		   behaviour of ldb_msg_find_element and
		   ldb_msg_remove_element */
		old_el = ldb_msg_find_element(msg, el->name);
		if (old_el != el) {
			ldb_msg_remove_element(msg, old_el);
			i--;
		}
	}

	talloc_free(res);
	return ret;
}



static int replmd_modify(struct ldb_module *module, struct ldb_request *req)
{
	struct ldb_context *ldb;
	struct replmd_replicated_request *ac;
	struct ldb_request *down_req;
	struct ldb_message *msg;
	time_t t = time(NULL);
	int ret;
	bool is_urgent = false;
	struct loadparm_context *lp_ctx;
	char *referral;
	unsigned int functional_level;

	/* do not manipulate our control entries */
	if (ldb_dn_is_special(req->op.mod.message->dn)) {
		return ldb_next_request(module, req);
	}

	ldb = ldb_module_get_ctx(module);
	functional_level = dsdb_functional_level(ldb);

	lp_ctx = talloc_get_type(ldb_get_opaque(ldb, "loadparm"),
				 struct loadparm_context);

	ldb_debug(ldb, LDB_DEBUG_TRACE, "replmd_modify\n");

	ac = replmd_ctx_init(module, req);
	if (!ac) {
		return LDB_ERR_OPERATIONS_ERROR;
	}

	/* we have to copy the message as the caller might have it as a const */
	msg = ldb_msg_copy_shallow(ac, req->op.mod.message);
	if (msg == NULL) {
		ldb_oom(ldb);
		talloc_free(ac);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	ldb_msg_remove_attr(msg, "whenChanged");
	ldb_msg_remove_attr(msg, "uSNChanged");

	ret = replmd_update_rpmd(module, ac->schema, req, msg, &ac->seq_num, t, &is_urgent);
	if (ret == LDB_ERR_REFERRAL) {
		referral = talloc_asprintf(req,
					   "ldap://%s/%s",
					   lpcfg_dnsdomain(lp_ctx),
					   ldb_dn_get_linearized(msg->dn));
		ret = ldb_module_send_referral(req, referral);
		talloc_free(ac);
		return ldb_module_done(req, NULL, NULL, ret);
	}

	if (ret != LDB_SUCCESS) {
		talloc_free(ac);
		return ret;
	}

	ret = replmd_modify_handle_linked_attribs(module, msg, ac->seq_num, t);
	if (ret != LDB_SUCCESS) {
		talloc_free(ac);
		return ret;
	}

	/* TODO:
	 * - replace the old object with the newly constructed one
	 */

	ac->is_urgent = is_urgent;

	ret = ldb_build_mod_req(&down_req, ldb, ac,
				msg,
				req->controls,
				ac, replmd_op_callback,
				req);
	if (ret != LDB_SUCCESS) {
		talloc_free(ac);
		return ret;
	}

	/* If we are in functional level 2000, then
	 * replmd_modify_handle_linked_attribs will have done
	 * nothing */
	if (functional_level == DS_DOMAIN_FUNCTION_2000) {
		ret = ldb_request_add_control(down_req, DSDB_CONTROL_APPLY_LINKS, false, NULL);
		if (ret != LDB_SUCCESS) {
			talloc_free(ac);
			return ret;
		}
	}

	talloc_steal(down_req, msg);

	/* we only change whenChanged and uSNChanged if the seq_num
	   has changed */
	if (ac->seq_num != 0) {
		if (add_time_element(msg, "whenChanged", t) != LDB_SUCCESS) {
			talloc_free(ac);
			return ret;
		}

		if (add_uint64_element(msg, "uSNChanged", ac->seq_num) != LDB_SUCCESS) {
			talloc_free(ac);
			return ret;
		}
	}

	/* go on with the call chain */
	return ldb_next_request(module, down_req);
}

static int replmd_rename_callback(struct ldb_request *req, struct ldb_reply *ares);

/*
  handle a rename request

  On a rename we need to do an extra ldb_modify which sets the
  whenChanged and uSNChanged attributes.  We do this in a callback after the success.
 */
static int replmd_rename(struct ldb_module *module, struct ldb_request *req)
{
	struct ldb_context *ldb;
	struct replmd_replicated_request *ac;
	int ret;
	struct ldb_request *down_req;

	/* do not manipulate our control entries */
	if (ldb_dn_is_special(req->op.mod.message->dn)) {
		return ldb_next_request(module, req);
	}

	ldb = ldb_module_get_ctx(module);

	ldb_debug(ldb, LDB_DEBUG_TRACE, "replmd_rename\n");

	ac = replmd_ctx_init(module, req);
	if (!ac) {
		return LDB_ERR_OPERATIONS_ERROR;
	}
	ret = ldb_build_rename_req(&down_req, ldb, ac,
				   ac->req->op.rename.olddn,
				   ac->req->op.rename.newdn,
				   ac->req->controls,
				   ac, replmd_rename_callback,
				   ac->req);

	if (ret != LDB_SUCCESS) {
		talloc_free(ac);
		return ret;
	}

	/* go on with the call chain */
	return ldb_next_request(module, down_req);
}

/* After the rename is compleated, update the whenchanged etc */
static int replmd_rename_callback(struct ldb_request *req, struct ldb_reply *ares)
{
	struct ldb_context *ldb;
	struct replmd_replicated_request *ac;
	struct ldb_request *down_req;
	struct ldb_message *msg;
	time_t t = time(NULL);
	int ret;

	ac = talloc_get_type(req->context, struct replmd_replicated_request);
	ldb = ldb_module_get_ctx(ac->module);

	if (ares->error != LDB_SUCCESS) {
		return ldb_module_done(ac->req, ares->controls,
					ares->response, ares->error);
	}

	if (ares->type != LDB_REPLY_DONE) {
		ldb_set_errstring(ldb,
				  "invalid ldb_reply_type in callback");
		talloc_free(ares);
		return ldb_module_done(ac->req, NULL, NULL,
					LDB_ERR_OPERATIONS_ERROR);
	}

	/* Get a sequence number from the backend */
	ret = ldb_sequence_number(ldb, LDB_SEQ_NEXT, &ac->seq_num);
	if (ret != LDB_SUCCESS) {
		return ret;
	}

	/* TODO:
	 * - replace the old object with the newly constructed one
	 */

	msg = ldb_msg_new(ac);
	if (msg == NULL) {
		ldb_oom(ldb);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	msg->dn = ac->req->op.rename.newdn;

	ret = ldb_build_mod_req(&down_req, ldb, ac,
				msg,
				req->controls,
				ac, replmd_op_callback,
				req);

	if (ret != LDB_SUCCESS) {
		talloc_free(ac);
		return ret;
	}
	talloc_steal(down_req, msg);

	if (add_time_element(msg, "whenChanged", t) != LDB_SUCCESS) {
		talloc_free(ac);
		return ret;
	}

	if (add_uint64_element(msg, "uSNChanged", ac->seq_num) != LDB_SUCCESS) {
		talloc_free(ac);
		return ret;
	}

	/* go on with the call chain - do the modify after the rename */
	return ldb_next_request(ac->module, down_req);
}

/*
   remove links from objects that point at this object when an object
   is deleted
 */
static int replmd_delete_remove_link(struct ldb_module *module,
				     const struct dsdb_schema *schema,
				     struct ldb_dn *dn,
				     struct ldb_message_element *el,
				     const struct dsdb_attribute *sa)
{
	unsigned int i;
	TALLOC_CTX *tmp_ctx = talloc_new(module);
	struct ldb_context *ldb = ldb_module_get_ctx(module);

	for (i=0; i<el->num_values; i++) {
		struct dsdb_dn *dsdb_dn;
		NTSTATUS status;
		int ret;
		struct GUID guid2;
		struct ldb_message *msg;
		const struct dsdb_attribute *target_attr;
		struct ldb_message_element *el2;
		struct ldb_val dn_val;

		if (dsdb_dn_is_deleted_val(&el->values[i])) {
			continue;
		}

		dsdb_dn = dsdb_dn_parse(tmp_ctx, ldb, &el->values[i], sa->syntax->ldap_oid);
		if (!dsdb_dn) {
			talloc_free(tmp_ctx);
			return LDB_ERR_OPERATIONS_ERROR;
		}

		status = dsdb_get_extended_dn_guid(dsdb_dn->dn, &guid2, "GUID");
		if (!NT_STATUS_IS_OK(status)) {
			talloc_free(tmp_ctx);
			return LDB_ERR_OPERATIONS_ERROR;
		}

		/* remove the link */
		msg = ldb_msg_new(tmp_ctx);
		if (!msg) {
			ldb_module_oom(module);
			talloc_free(tmp_ctx);
			return LDB_ERR_OPERATIONS_ERROR;
		}


		msg->dn = dsdb_dn->dn;

		target_attr = dsdb_attribute_by_linkID(schema, sa->linkID ^ 1);
		if (target_attr == NULL) {
			continue;
		}

		ret = ldb_msg_add_empty(msg, target_attr->lDAPDisplayName, LDB_FLAG_MOD_DELETE, &el2);
		if (ret != LDB_SUCCESS) {
			ldb_module_oom(module);
			talloc_free(tmp_ctx);
			return LDB_ERR_OPERATIONS_ERROR;
		}
		dn_val = data_blob_string_const(ldb_dn_get_linearized(dn));
		el2->values = &dn_val;
		el2->num_values = 1;

		ret = dsdb_module_modify(module, msg, DSDB_FLAG_OWN_MODULE);
		if (ret != LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			return ret;
		}
	}
	talloc_free(tmp_ctx);
	return LDB_SUCCESS;
}


/*
  handle update of replication meta data for deletion of objects

  This also handles the mapping of delete to a rename operation
  to allow deletes to be replicated.
 */
static int replmd_delete(struct ldb_module *module, struct ldb_request *req)
{
	int ret = LDB_ERR_OTHER;
	bool retb;
	struct ldb_dn *old_dn, *new_dn;
	const char *rdn_name;
	const struct ldb_val *rdn_value, *new_rdn_value;
	struct GUID guid;
	struct ldb_context *ldb = ldb_module_get_ctx(module);
	const struct dsdb_schema *schema;
	struct ldb_message *msg, *old_msg;
	struct ldb_message_element *el;
	TALLOC_CTX *tmp_ctx;
	struct ldb_result *res, *parent_res;
	const char *preserved_attrs[] = {
		/* yes, this really is a hard coded list. See MS-ADTS
		   section 3.1.1.5.5.1.1 */
		"nTSecurityDescriptor", "attributeID", "attributeSyntax", "dNReferenceUpdate", "dNSHostName",
		"flatName", "governsID", "groupType", "instanceType", "lDAPDisplayName", "legacyExchangeDN",
		"isDeleted", "isRecycled", "lastKnownParent", "msDS-LastKnownRDN", "mS-DS-CreatorSID",
		"mSMQOwnerID", "nCName", "objectClass", "distinguishedName", "objectGUID", "objectSid",
		"oMSyntax", "proxiedObjectName", "name", "replPropertyMetaData", "sAMAccountName",
		"securityIdentifier", "sIDHistory", "subClassOf", "systemFlags", "trustPartner", "trustDirection",
		"trustType", "trustAttributes", "userAccountControl", "uSNChanged", "uSNCreated", "whenCreated",
		"whenChanged", NULL};
	unsigned int i, el_count = 0;
	enum deletion_state { OBJECT_NOT_DELETED=1, OBJECT_DELETED=2, OBJECT_RECYCLED=3,
						OBJECT_TOMBSTONE=4, OBJECT_REMOVED=5 };
	enum deletion_state deletion_state, next_deletion_state;
	bool enabled;

	if (ldb_dn_is_special(req->op.del.dn)) {
		return ldb_next_request(module, req);
	}

	tmp_ctx = talloc_new(ldb);
	if (!tmp_ctx) {
		ldb_oom(ldb);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	schema = dsdb_get_schema(ldb, tmp_ctx);
	if (!schema) {
		return LDB_ERR_OPERATIONS_ERROR;
	}

	old_dn = ldb_dn_copy(tmp_ctx, req->op.del.dn);

	/* we need the complete msg off disk, so we can work out which
	   attributes need to be removed */
	ret = dsdb_module_search_dn(module, tmp_ctx, &res, old_dn, NULL,
	                            DSDB_FLAG_NEXT_MODULE |
	                            DSDB_SEARCH_SHOW_DELETED |
				    DSDB_SEARCH_REVEAL_INTERNALS |
				    DSDB_SEARCH_SHOW_DN_IN_STORAGE_FORMAT);
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}
	old_msg = res->msgs[0];


	ret = dsdb_recyclebin_enabled(module, &enabled);
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}

	if (ldb_msg_check_string_attribute(old_msg, "isDeleted", "TRUE")) {
		if (!enabled) {
			deletion_state = OBJECT_TOMBSTONE;
			next_deletion_state = OBJECT_REMOVED;
		} else if (ldb_msg_check_string_attribute(old_msg, "isRecycled", "TRUE")) {
			deletion_state = OBJECT_RECYCLED;
			next_deletion_state = OBJECT_REMOVED;
		} else {
			deletion_state = OBJECT_DELETED;
			next_deletion_state = OBJECT_RECYCLED;
		}
	} else {
		deletion_state = OBJECT_NOT_DELETED;
		if (enabled) {
			next_deletion_state = OBJECT_DELETED;
		} else {
			next_deletion_state = OBJECT_TOMBSTONE;
		}
	}

	if (next_deletion_state == OBJECT_REMOVED) {
		struct auth_session_info *session_info =
				(struct auth_session_info *)ldb_get_opaque(ldb, "sessionInfo");
		if (security_session_user_level(session_info, NULL) != SECURITY_SYSTEM) {
			ldb_asprintf_errstring(ldb, "Refusing to delete deleted object %s",
					ldb_dn_get_linearized(old_msg->dn));
			return LDB_ERR_UNWILLING_TO_PERFORM;
		}

		/* it is already deleted - really remove it this time */
		talloc_free(tmp_ctx);
		return ldb_next_request(module, req);
	}

	rdn_name = ldb_dn_get_rdn_name(old_dn);
	rdn_value = ldb_dn_get_rdn_val(old_dn);

	msg = ldb_msg_new(tmp_ctx);
	if (msg == NULL) {
		ldb_module_oom(module);
		talloc_free(tmp_ctx);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	msg->dn = old_dn;

	if (deletion_state == OBJECT_NOT_DELETED){
		/* work out where we will be renaming this object to */
		ret = dsdb_get_deleted_objects_dn(ldb, tmp_ctx, old_dn, &new_dn);
		if (ret != LDB_SUCCESS) {
			/* this is probably an attempted delete on a partition
			 * that doesn't allow delete operations, such as the
			 * schema partition */
			ldb_asprintf_errstring(ldb, "No Deleted Objects container for DN %s",
						   ldb_dn_get_linearized(old_dn));
			talloc_free(tmp_ctx);
			return LDB_ERR_UNWILLING_TO_PERFORM;
		}

		/* get the objects GUID from the search we just did */
		guid = samdb_result_guid(old_msg, "objectGUID");

		/* Add a formatted child */
		retb = ldb_dn_add_child_fmt(new_dn, "%s=%s\\0ADEL:%s",
						rdn_name,
						rdn_value->data,
						GUID_string(tmp_ctx, &guid));
		if (!retb) {
			DEBUG(0,(__location__ ": Unable to add a formatted child to dn: %s",
					ldb_dn_get_linearized(new_dn)));
			talloc_free(tmp_ctx);
			return LDB_ERR_OPERATIONS_ERROR;
		}

		ret = ldb_msg_add_string(msg, "isDeleted", "TRUE");
		if (ret != LDB_SUCCESS) {
			DEBUG(0,(__location__ ": Failed to add isDeleted string to the msg\n"));
			ldb_module_oom(module);
			talloc_free(tmp_ctx);
			return ret;
		}
		msg->elements[el_count++].flags = LDB_FLAG_MOD_ADD;
	}

	/*
	  now we need to modify the object in the following ways:

	  - add isDeleted=TRUE
	  - update rDN and name, with new rDN
	  - remove linked attributes
	  - remove objectCategory and sAMAccountType
	  - remove attribs not on the preserved list
	     - preserved if in above list, or is rDN
	  - remove all linked attribs from this object
	  - remove all links from other objects to this object
	  - add lastKnownParent
	  - update replPropertyMetaData?

	  see MS-ADTS "Tombstone Requirements" section 3.1.1.5.5.1.1
	 */

	/* we need the storage form of the parent GUID */
	ret = dsdb_module_search_dn(module, tmp_ctx, &parent_res,
				    ldb_dn_get_parent(tmp_ctx, old_dn), NULL,
				    DSDB_FLAG_NEXT_MODULE |
				    DSDB_SEARCH_SHOW_DN_IN_STORAGE_FORMAT |
				    DSDB_SEARCH_REVEAL_INTERNALS|
				    DSDB_SEARCH_SHOW_DELETED);
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}

	if (deletion_state == OBJECT_NOT_DELETED){
		ret = ldb_msg_add_steal_string(msg, "lastKnownParent",
						   ldb_dn_get_extended_linearized(tmp_ctx, parent_res->msgs[0]->dn, 1));
		if (ret != LDB_SUCCESS) {
			DEBUG(0,(__location__ ": Failed to add lastKnownParent string to the msg\n"));
			ldb_module_oom(module);
			talloc_free(tmp_ctx);
			return ret;
		}
		msg->elements[el_count++].flags = LDB_FLAG_MOD_ADD;
	}

	switch (next_deletion_state){

	case OBJECT_DELETED:

		ret = ldb_msg_add_value(msg, "msDS-LastKnownRDN", rdn_value, NULL);
		if (ret != LDB_SUCCESS) {
			DEBUG(0,(__location__ ": Failed to add msDS-LastKnownRDN string to the msg\n"));
			ldb_module_oom(module);
			talloc_free(tmp_ctx);
			return ret;
		}
		msg->elements[el_count++].flags = LDB_FLAG_MOD_ADD;

		ret = ldb_msg_add_empty(msg, "objectCategory", LDB_FLAG_MOD_DELETE, NULL);
		if (ret != LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			ldb_module_oom(module);
			return ret;
		}

		ret = ldb_msg_add_empty(msg, "sAMAccountType", LDB_FLAG_MOD_DELETE, NULL);
		if (ret != LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			ldb_module_oom(module);
			return ret;
		}

		break;

	case OBJECT_RECYCLED:
	case OBJECT_TOMBSTONE:

		/* we also mark it as recycled, meaning this object can't be
		   recovered (we are stripping its attributes) */
		if (dsdb_functional_level(ldb) >= DS_DOMAIN_FUNCTION_2008_R2) {
			ret = ldb_msg_add_string(msg, "isRecycled", "TRUE");
			if (ret != LDB_SUCCESS) {
				DEBUG(0,(__location__ ": Failed to add isRecycled string to the msg\n"));
				ldb_module_oom(module);
				talloc_free(tmp_ctx);
				return ret;
			}
			msg->elements[el_count++].flags = LDB_FLAG_MOD_ADD;
		}

		/* work out which of the old attributes we will be removing */
		for (i=0; i<old_msg->num_elements; i++) {
			const struct dsdb_attribute *sa;
			el = &old_msg->elements[i];
			sa = dsdb_attribute_by_lDAPDisplayName(schema, el->name);
			if (!sa) {
				talloc_free(tmp_ctx);
				return LDB_ERR_OPERATIONS_ERROR;
			}
			if (ldb_attr_cmp(el->name, rdn_name) == 0) {
				/* don't remove the rDN */
				continue;
			}
			if (sa->linkID && sa->linkID & 1) {
				ret = replmd_delete_remove_link(module, schema, old_dn, el, sa);
				if (ret != LDB_SUCCESS) {
					talloc_free(tmp_ctx);
					return LDB_ERR_OPERATIONS_ERROR;
				}
				continue;
			}
			if (!sa->linkID && ldb_attr_in_list(preserved_attrs, el->name)) {
				continue;
			}
			ret = ldb_msg_add_empty(msg, el->name, LDB_FLAG_MOD_DELETE, &el);
			if (ret != LDB_SUCCESS) {
				talloc_free(tmp_ctx);
				ldb_module_oom(module);
				return ret;
			}
		}
		break;

	default:
		break;
	}

	if (deletion_state == OBJECT_NOT_DELETED) {
		/* work out what the new rdn value is, for updating the
		   rDN and name fields */
		new_rdn_value = ldb_dn_get_rdn_val(new_dn);

		ret = ldb_msg_add_value(msg, strlower_talloc(tmp_ctx, rdn_name), new_rdn_value, &el);
		if (ret != LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			return ret;
		}
		el->flags = LDB_FLAG_MOD_REPLACE;

		el = ldb_msg_find_element(old_msg, "name");
		if (el) {
			ret = ldb_msg_add_value(msg, "name", new_rdn_value, &el);
			if (ret != LDB_SUCCESS) {
				talloc_free(tmp_ctx);
				return ret;
			}
			el->flags = LDB_FLAG_MOD_REPLACE;
		}
	}

	ret = dsdb_module_modify(module, msg, DSDB_FLAG_OWN_MODULE);
	if (ret != LDB_SUCCESS) {
		ldb_asprintf_errstring(ldb, "replmd_delete: Failed to modify object %s in delete - %s",
				       ldb_dn_get_linearized(old_dn), ldb_errstring(ldb));
		talloc_free(tmp_ctx);
		return ret;
	}

	if (deletion_state == OBJECT_NOT_DELETED) {
		/* now rename onto the new DN */
		ret = dsdb_module_rename(module, old_dn, new_dn, DSDB_FLAG_NEXT_MODULE);
		if (ret != LDB_SUCCESS){
			DEBUG(0,(__location__ ": Failed to rename object from '%s' to '%s' - %s\n",
				 ldb_dn_get_linearized(old_dn),
				 ldb_dn_get_linearized(new_dn),
				 ldb_errstring(ldb)));
			talloc_free(tmp_ctx);
			return ret;
		}
	}

	talloc_free(tmp_ctx);

	return ldb_module_done(req, NULL, NULL, LDB_SUCCESS);
}



static int replmd_replicated_request_error(struct replmd_replicated_request *ar, int ret)
{
	return ret;
}

static int replmd_replicated_request_werror(struct replmd_replicated_request *ar, WERROR status)
{
	int ret = LDB_ERR_OTHER;
	/* TODO: do some error mapping */
	return ret;
}

static int replmd_replicated_apply_add(struct replmd_replicated_request *ar)
{
	struct ldb_context *ldb;
	struct ldb_request *change_req;
	enum ndr_err_code ndr_err;
	struct ldb_message *msg;
	struct replPropertyMetaDataBlob *md;
	struct ldb_val md_value;
	unsigned int i;
	int ret;

	/*
	 * TODO: check if the parent object exist
	 */

	/*
	 * TODO: handle the conflict case where an object with the
	 *       same name exist
	 */

	ldb = ldb_module_get_ctx(ar->module);
	msg = ar->objs->objects[ar->index_current].msg;
	md = ar->objs->objects[ar->index_current].meta_data;

	ret = ldb_sequence_number(ldb, LDB_SEQ_NEXT, &ar->seq_num);
	if (ret != LDB_SUCCESS) {
		return replmd_replicated_request_error(ar, ret);
	}

	ret = ldb_msg_add_value(msg, "objectGUID", &ar->objs->objects[ar->index_current].guid_value, NULL);
	if (ret != LDB_SUCCESS) {
		return replmd_replicated_request_error(ar, ret);
	}

	ret = ldb_msg_add_string(msg, "whenChanged", ar->objs->objects[ar->index_current].when_changed);
	if (ret != LDB_SUCCESS) {
		return replmd_replicated_request_error(ar, ret);
	}

	ret = samdb_msg_add_uint64(ldb, msg, msg, "uSNCreated", ar->seq_num);
	if (ret != LDB_SUCCESS) {
		return replmd_replicated_request_error(ar, ret);
	}

	ret = samdb_msg_add_uint64(ldb, msg, msg, "uSNChanged", ar->seq_num);
	if (ret != LDB_SUCCESS) {
		return replmd_replicated_request_error(ar, ret);
	}

	/* remove any message elements that have zero values */
	for (i=0; i<msg->num_elements; i++) {
		struct ldb_message_element *el = &msg->elements[i];

		if (el->num_values == 0) {
			DEBUG(4,(__location__ ": Removing attribute %s with num_values==0\n",
				 el->name));
			memmove(el, el+1, sizeof(*el)*(msg->num_elements - (i+1)));
			msg->num_elements--;
			i--;
			continue;
		}
	}

	/*
	 * the meta data array is already sorted by the caller
	 */
	for (i=0; i < md->ctr.ctr1.count; i++) {
		md->ctr.ctr1.array[i].local_usn = ar->seq_num;
	}
	ndr_err = ndr_push_struct_blob(&md_value, msg, md,
				       (ndr_push_flags_fn_t)ndr_push_replPropertyMetaDataBlob);
	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
		NTSTATUS nt_status = ndr_map_error2ntstatus(ndr_err);
		return replmd_replicated_request_werror(ar, ntstatus_to_werror(nt_status));
	}
	ret = ldb_msg_add_value(msg, "replPropertyMetaData", &md_value, NULL);
	if (ret != LDB_SUCCESS) {
		return replmd_replicated_request_error(ar, ret);
	}

	replmd_ldb_message_sort(msg, ar->schema);

	if (DEBUGLVL(4)) {
		char *s = ldb_ldif_message_string(ldb, ar, LDB_CHANGETYPE_ADD, msg);
		DEBUG(4, ("DRS replication add message:\n%s\n", s));
		talloc_free(s);
	}

	ret = ldb_build_add_req(&change_req,
				ldb,
				ar,
				msg,
				ar->controls,
				ar,
				replmd_op_callback,
				ar->req);
	if (ret != LDB_SUCCESS) return replmd_replicated_request_error(ar, ret);

	return ldb_next_request(ar->module, change_req);
}

/*
   return true if an update is newer than an existing entry
   see section 5.11 of MS-ADTS
*/
static bool replmd_update_is_newer(const struct GUID *current_invocation_id,
				   const struct GUID *update_invocation_id,
				   uint32_t current_version,
				   uint32_t update_version,
				   NTTIME current_change_time,
				   NTTIME update_change_time)
{
	if (update_version != current_version) {
		return update_version > current_version;
	}
	if (update_change_time > current_change_time) {
		return true;
	}
	if (update_change_time == current_change_time) {
		return GUID_compare(update_invocation_id, current_invocation_id) > 0;
	}
	return false;
}

static bool replmd_replPropertyMetaData1_is_newer(struct replPropertyMetaData1 *cur_m,
						  struct replPropertyMetaData1 *new_m)
{
	return replmd_update_is_newer(&cur_m->originating_invocation_id,
				      &new_m->originating_invocation_id,
				      cur_m->version,
				      new_m->version,
				      cur_m->originating_change_time,
				      new_m->originating_change_time);
}

static struct replPropertyMetaData1 *
replmd_replPropertyMetaData1_find_attid(struct replPropertyMetaDataBlob *md_blob,
                                        enum drsuapi_DsAttributeId attid)
{
	uint32_t i;
	struct replPropertyMetaDataCtr1 *rpmd_ctr = &md_blob->ctr.ctr1;

	for (i = 0; i < rpmd_ctr->count; i++) {
		if (rpmd_ctr->array[i].attid == attid) {
			return &rpmd_ctr->array[i];
		}
	}
	return NULL;
}

static int replmd_replicated_apply_merge(struct replmd_replicated_request *ar)
{
	struct ldb_context *ldb;
	struct ldb_request *change_req;
	enum ndr_err_code ndr_err;
	struct ldb_message *msg;
	struct replPropertyMetaDataBlob *rmd;
	struct replPropertyMetaDataBlob omd;
	const struct ldb_val *omd_value;
	struct replPropertyMetaDataBlob nmd;
	struct ldb_val nmd_value;
	struct replPropertyMetaData1 *md_remote;
	struct replPropertyMetaData1 *md_local;
	unsigned int i;
	uint32_t j,ni=0;
	unsigned int removed_attrs = 0;
	int ret;

	ldb = ldb_module_get_ctx(ar->module);
	msg = ar->objs->objects[ar->index_current].msg;
	rmd = ar->objs->objects[ar->index_current].meta_data;
	ZERO_STRUCT(omd);
	omd.version = 1;

	/* find existing meta data */
	omd_value = ldb_msg_find_ldb_val(ar->search_msg, "replPropertyMetaData");
	if (omd_value) {
		ndr_err = ndr_pull_struct_blob(omd_value, ar, &omd,
					       (ndr_pull_flags_fn_t)ndr_pull_replPropertyMetaDataBlob);
		if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
			NTSTATUS nt_status = ndr_map_error2ntstatus(ndr_err);
			return replmd_replicated_request_werror(ar, ntstatus_to_werror(nt_status));
		}

		if (omd.version != 1) {
			return replmd_replicated_request_werror(ar, WERR_DS_DRA_INTERNAL_ERROR);
		}
	}

	/* check if remote 'name' has change,
	 * which indicates a rename operation */
	md_remote = replmd_replPropertyMetaData1_find_attid(rmd, DRSUAPI_ATTRIBUTE_name);
	if (md_remote) {
		md_local = replmd_replPropertyMetaData1_find_attid(&omd, DRSUAPI_ATTRIBUTE_name);
		SMB_ASSERT(md_local);
		if (replmd_replPropertyMetaData1_is_newer(md_local, md_remote)) {
			SMB_ASSERT(ldb_dn_compare(msg->dn, ar->search_msg->dn) != 0);
			/* TODO: Find appropriate local name (dn) for the object
			 *       and modify msg->dn appropriately */

			DEBUG(4,("replmd_replicated_request rename %s => %s\n",
				  ldb_dn_get_linearized(ar->search_msg->dn),
				  ldb_dn_get_linearized(msg->dn)));
			/* pass rename to the next module
			 * so it doesn't appear as an originating update */
			ret = dsdb_module_rename(ar->module,
			                         ar->search_msg->dn, msg->dn,
			                         DSDB_FLAG_NEXT_MODULE);
			if (ret != LDB_SUCCESS) {
				ldb_debug(ldb, LDB_DEBUG_FATAL,
				          "replmd_replicated_request rename %s => %s failed - %s\n",
					  ldb_dn_get_linearized(ar->search_msg->dn),
					  ldb_dn_get_linearized(msg->dn),
					  ldb_errstring(ldb));
				return replmd_replicated_request_werror(ar, WERR_DS_DRA_DB_ERROR);
			}
		}
	}

	ZERO_STRUCT(nmd);
	nmd.version = 1;
	nmd.ctr.ctr1.count = omd.ctr.ctr1.count + rmd->ctr.ctr1.count;
	nmd.ctr.ctr1.array = talloc_array(ar,
					  struct replPropertyMetaData1,
					  nmd.ctr.ctr1.count);
	if (!nmd.ctr.ctr1.array) return replmd_replicated_request_werror(ar, WERR_NOMEM);

	/* first copy the old meta data */
	for (i=0; i < omd.ctr.ctr1.count; i++) {
		nmd.ctr.ctr1.array[ni]	= omd.ctr.ctr1.array[i];
		ni++;
	}

	/* now merge in the new meta data */
	for (i=0; i < rmd->ctr.ctr1.count; i++) {
		bool found = false;

		for (j=0; j < ni; j++) {
			bool cmp;

			if (rmd->ctr.ctr1.array[i].attid != nmd.ctr.ctr1.array[j].attid) {
				continue;
			}

			cmp = replmd_replPropertyMetaData1_is_newer(&nmd.ctr.ctr1.array[j],
								    &rmd->ctr.ctr1.array[i]);
			if (cmp) {
				/* replace the entry */
				nmd.ctr.ctr1.array[j] = rmd->ctr.ctr1.array[i];
				found = true;
				break;
			}

			if (rmd->ctr.ctr1.array[i].attid != DRSUAPI_ATTRIBUTE_instanceType) {
				DEBUG(3,("Discarding older DRS attribute update to %s on %s from %s\n",
					 msg->elements[i-removed_attrs].name,
					 ldb_dn_get_linearized(msg->dn),
					 GUID_string(ar, &rmd->ctr.ctr1.array[i].originating_invocation_id)));
			}

			/* we don't want to apply this change so remove the attribute */
			ldb_msg_remove_element(msg, &msg->elements[i-removed_attrs]);
			removed_attrs++;

			found = true;
			break;
		}

		if (found) continue;

		nmd.ctr.ctr1.array[ni] = rmd->ctr.ctr1.array[i];
		ni++;
	}

	/*
	 * finally correct the size of the meta_data array
	 */
	nmd.ctr.ctr1.count = ni;

	/*
	 * the rdn attribute (the alias for the name attribute),
	 * 'cn' for most objects is the last entry in the meta data array
	 * we have stored
	 *
	 * sort the new meta data array
	 */
	ret = replmd_replPropertyMetaDataCtr1_sort(&nmd.ctr.ctr1, ar->schema, msg->dn);
	if (ret != LDB_SUCCESS) {
		return ret;
	}

	/*
	 * check if some replicated attributes left, otherwise skip the ldb_modify() call
	 */
	if (msg->num_elements == 0) {
		ldb_debug(ldb, LDB_DEBUG_TRACE, "replmd_replicated_apply_merge[%u]: skip replace\n",
			  ar->index_current);

		ar->index_current++;
		return replmd_replicated_apply_next(ar);
	}

	ldb_debug(ldb, LDB_DEBUG_TRACE, "replmd_replicated_apply_merge[%u]: replace %u attributes\n",
		  ar->index_current, msg->num_elements);

	ret = ldb_sequence_number(ldb, LDB_SEQ_NEXT, &ar->seq_num);
	if (ret != LDB_SUCCESS) {
		return replmd_replicated_request_error(ar, ret);
	}

	for (i=0; i<ni; i++) {
		nmd.ctr.ctr1.array[i].local_usn = ar->seq_num;
	}

	/* create the meta data value */
	ndr_err = ndr_push_struct_blob(&nmd_value, msg, &nmd,
				       (ndr_push_flags_fn_t)ndr_push_replPropertyMetaDataBlob);
	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
		NTSTATUS nt_status = ndr_map_error2ntstatus(ndr_err);
		return replmd_replicated_request_werror(ar, ntstatus_to_werror(nt_status));
	}

	/*
	 * when we know that we'll modify the record, add the whenChanged, uSNChanged
	 * and replPopertyMetaData attributes
	 */
	ret = ldb_msg_add_string(msg, "whenChanged", ar->objs->objects[ar->index_current].when_changed);
	if (ret != LDB_SUCCESS) {
		return replmd_replicated_request_error(ar, ret);
	}
	ret = samdb_msg_add_uint64(ldb, msg, msg, "uSNChanged", ar->seq_num);
	if (ret != LDB_SUCCESS) {
		return replmd_replicated_request_error(ar, ret);
	}
	ret = ldb_msg_add_value(msg, "replPropertyMetaData", &nmd_value, NULL);
	if (ret != LDB_SUCCESS) {
		return replmd_replicated_request_error(ar, ret);
	}

	replmd_ldb_message_sort(msg, ar->schema);

	/* we want to replace the old values */
	for (i=0; i < msg->num_elements; i++) {
		msg->elements[i].flags = LDB_FLAG_MOD_REPLACE;
	}

	if (DEBUGLVL(4)) {
		char *s = ldb_ldif_message_string(ldb, ar, LDB_CHANGETYPE_MODIFY, msg);
		DEBUG(4, ("DRS replication modify message:\n%s\n", s));
		talloc_free(s);
	}

	ret = ldb_build_mod_req(&change_req,
				ldb,
				ar,
				msg,
				ar->controls,
				ar,
				replmd_op_callback,
				ar->req);
	if (ret != LDB_SUCCESS) return replmd_replicated_request_error(ar, ret);

	return ldb_next_request(ar->module, change_req);
}

static int replmd_replicated_apply_search_callback(struct ldb_request *req,
						   struct ldb_reply *ares)
{
	struct replmd_replicated_request *ar = talloc_get_type(req->context,
					       struct replmd_replicated_request);
	int ret;

	if (!ares) {
		return ldb_module_done(ar->req, NULL, NULL,
					LDB_ERR_OPERATIONS_ERROR);
	}
	if (ares->error != LDB_SUCCESS &&
	    ares->error != LDB_ERR_NO_SUCH_OBJECT) {
		return ldb_module_done(ar->req, ares->controls,
					ares->response, ares->error);
	}

	switch (ares->type) {
	case LDB_REPLY_ENTRY:
		ar->search_msg = talloc_steal(ar, ares->message);
		break;

	case LDB_REPLY_REFERRAL:
		/* we ignore referrals */
		break;

	case LDB_REPLY_DONE:
		if (ar->search_msg != NULL) {
			ret = replmd_replicated_apply_merge(ar);
		} else {
			ret = replmd_replicated_apply_add(ar);
		}
		if (ret != LDB_SUCCESS) {
			return ldb_module_done(ar->req, NULL, NULL, ret);
		}
	}

	talloc_free(ares);
	return LDB_SUCCESS;
}

static int replmd_replicated_uptodate_vector(struct replmd_replicated_request *ar);

static int replmd_replicated_apply_next(struct replmd_replicated_request *ar)
{
	struct ldb_context *ldb;
	int ret;
	char *tmp_str;
	char *filter;
	struct ldb_request *search_req;
	struct ldb_search_options_control *options;

	if (ar->index_current >= ar->objs->num_objects) {
		/* done with it, go to next stage */
		return replmd_replicated_uptodate_vector(ar);
	}

	ldb = ldb_module_get_ctx(ar->module);
	ar->search_msg = NULL;

	tmp_str = ldb_binary_encode(ar, ar->objs->objects[ar->index_current].guid_value);
	if (!tmp_str) return replmd_replicated_request_werror(ar, WERR_NOMEM);

	filter = talloc_asprintf(ar, "(objectGUID=%s)", tmp_str);
	if (!filter) return replmd_replicated_request_werror(ar, WERR_NOMEM);
	talloc_free(tmp_str);

	ret = ldb_build_search_req(&search_req,
				   ldb,
				   ar,
				   NULL,
				   LDB_SCOPE_SUBTREE,
				   filter,
				   NULL,
				   NULL,
				   ar,
				   replmd_replicated_apply_search_callback,
				   ar->req);

	ret = ldb_request_add_control(search_req, LDB_CONTROL_SHOW_DELETED_OID, true, NULL);
	if (ret != LDB_SUCCESS) {
		return ret;
	}

	/* we need to cope with cross-partition links, so search for
	   the GUID over all partitions */
	options = talloc(search_req, struct ldb_search_options_control);
	if (options == NULL) {
		DEBUG(0, (__location__ ": out of memory\n"));
		return LDB_ERR_OPERATIONS_ERROR;
	}
	options->search_options = LDB_SEARCH_OPTION_PHANTOM_ROOT;

	ret = ldb_request_add_control(search_req,
				      LDB_CONTROL_SEARCH_OPTIONS_OID,
				      true, options);
	if (ret != LDB_SUCCESS) {
		return ret;
	}

	if (ret != LDB_SUCCESS) return replmd_replicated_request_error(ar, ret);

	return ldb_next_request(ar->module, search_req);
}

static int replmd_replicated_uptodate_modify_callback(struct ldb_request *req,
						      struct ldb_reply *ares)
{
	struct ldb_context *ldb;
	struct replmd_replicated_request *ar = talloc_get_type(req->context,
					       struct replmd_replicated_request);
	ldb = ldb_module_get_ctx(ar->module);

	if (!ares) {
		return ldb_module_done(ar->req, NULL, NULL,
					LDB_ERR_OPERATIONS_ERROR);
	}
	if (ares->error != LDB_SUCCESS) {
		return ldb_module_done(ar->req, ares->controls,
					ares->response, ares->error);
	}

	if (ares->type != LDB_REPLY_DONE) {
		ldb_set_errstring(ldb, "Invalid reply type\n!");
		return ldb_module_done(ar->req, NULL, NULL,
					LDB_ERR_OPERATIONS_ERROR);
	}

	talloc_free(ares);

	return ldb_module_done(ar->req, NULL, NULL, LDB_SUCCESS);
}

static int replmd_replicated_uptodate_modify(struct replmd_replicated_request *ar)
{
	struct ldb_context *ldb;
	struct ldb_request *change_req;
	enum ndr_err_code ndr_err;
	struct ldb_message *msg;
	struct replUpToDateVectorBlob ouv;
	const struct ldb_val *ouv_value;
	const struct drsuapi_DsReplicaCursor2CtrEx *ruv;
	struct replUpToDateVectorBlob nuv;
	struct ldb_val nuv_value;
	struct ldb_message_element *nuv_el = NULL;
	const struct GUID *our_invocation_id;
	struct ldb_message_element *orf_el = NULL;
	struct repsFromToBlob nrf;
	struct ldb_val *nrf_value = NULL;
	struct ldb_message_element *nrf_el = NULL;
	unsigned int i;
	uint32_t j,ni=0;
	bool found = false;
	time_t t = time(NULL);
	NTTIME now;
	int ret;

	ldb = ldb_module_get_ctx(ar->module);
	ruv = ar->objs->uptodateness_vector;
	ZERO_STRUCT(ouv);
	ouv.version = 2;
	ZERO_STRUCT(nuv);
	nuv.version = 2;

	unix_to_nt_time(&now, t);

	/*
	 * first create the new replUpToDateVector
	 */
	ouv_value = ldb_msg_find_ldb_val(ar->search_msg, "replUpToDateVector");
	if (ouv_value) {
		ndr_err = ndr_pull_struct_blob(ouv_value, ar, &ouv,
					       (ndr_pull_flags_fn_t)ndr_pull_replUpToDateVectorBlob);
		if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
			NTSTATUS nt_status = ndr_map_error2ntstatus(ndr_err);
			return replmd_replicated_request_werror(ar, ntstatus_to_werror(nt_status));
		}

		if (ouv.version != 2) {
			return replmd_replicated_request_werror(ar, WERR_DS_DRA_INTERNAL_ERROR);
		}
	}

	/*
	 * the new uptodateness vector will at least
	 * contain 1 entry, one for the source_dsa
	 *
	 * plus optional values from our old vector and the one from the source_dsa
	 */
	nuv.ctr.ctr2.count = 1 + ouv.ctr.ctr2.count;
	if (ruv) nuv.ctr.ctr2.count += ruv->count;
	nuv.ctr.ctr2.cursors = talloc_array(ar,
					    struct drsuapi_DsReplicaCursor2,
					    nuv.ctr.ctr2.count);
	if (!nuv.ctr.ctr2.cursors) return replmd_replicated_request_werror(ar, WERR_NOMEM);

	/* first copy the old vector */
	for (i=0; i < ouv.ctr.ctr2.count; i++) {
		nuv.ctr.ctr2.cursors[ni] = ouv.ctr.ctr2.cursors[i];
		ni++;
	}

	/* get our invocation_id if we have one already attached to the ldb */
	our_invocation_id = samdb_ntds_invocation_id(ldb);

	/* merge in the source_dsa vector is available */
	for (i=0; (ruv && i < ruv->count); i++) {
		found = false;

		if (our_invocation_id &&
		    GUID_equal(&ruv->cursors[i].source_dsa_invocation_id,
			       our_invocation_id)) {
			continue;
		}

		for (j=0; j < ni; j++) {
			if (!GUID_equal(&ruv->cursors[i].source_dsa_invocation_id,
					&nuv.ctr.ctr2.cursors[j].source_dsa_invocation_id)) {
				continue;
			}

			found = true;

			/*
			 * we update only the highest_usn and not the latest_sync_success time,
			 * because the last success stands for direct replication
			 */
			if (ruv->cursors[i].highest_usn > nuv.ctr.ctr2.cursors[j].highest_usn) {
				nuv.ctr.ctr2.cursors[j].highest_usn = ruv->cursors[i].highest_usn;
			}
			break;
		}

		if (found) continue;

		/* if it's not there yet, add it */
		nuv.ctr.ctr2.cursors[ni] = ruv->cursors[i];
		ni++;
	}

	/*
	 * merge in the current highwatermark for the source_dsa
	 */
	found = false;
	for (j=0; j < ni; j++) {
		if (!GUID_equal(&ar->objs->source_dsa->source_dsa_invocation_id,
				&nuv.ctr.ctr2.cursors[j].source_dsa_invocation_id)) {
			continue;
		}

		found = true;

		/*
		 * here we update the highest_usn and last_sync_success time
		 * because we're directly replicating from the source_dsa
		 *
		 * and use the tmp_highest_usn because this is what we have just applied
		 * to our ldb
		 */
		nuv.ctr.ctr2.cursors[j].highest_usn		= ar->objs->source_dsa->highwatermark.tmp_highest_usn;
		nuv.ctr.ctr2.cursors[j].last_sync_success	= now;
		break;
	}
	if (!found) {
		/*
		 * here we update the highest_usn and last_sync_success time
		 * because we're directly replicating from the source_dsa
		 *
		 * and use the tmp_highest_usn because this is what we have just applied
		 * to our ldb
		 */
		nuv.ctr.ctr2.cursors[ni].source_dsa_invocation_id= ar->objs->source_dsa->source_dsa_invocation_id;
		nuv.ctr.ctr2.cursors[ni].highest_usn		= ar->objs->source_dsa->highwatermark.tmp_highest_usn;
		nuv.ctr.ctr2.cursors[ni].last_sync_success	= now;
		ni++;
	}

	/*
	 * finally correct the size of the cursors array
	 */
	nuv.ctr.ctr2.count = ni;

	/*
	 * sort the cursors
	 */
	TYPESAFE_QSORT(nuv.ctr.ctr2.cursors, nuv.ctr.ctr2.count, drsuapi_DsReplicaCursor2_compare);

	/*
	 * create the change ldb_message
	 */
	msg = ldb_msg_new(ar);
	if (!msg) return replmd_replicated_request_werror(ar, WERR_NOMEM);
	msg->dn = ar->search_msg->dn;

	ndr_err = ndr_push_struct_blob(&nuv_value, msg, &nuv,
				       (ndr_push_flags_fn_t)ndr_push_replUpToDateVectorBlob);
	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
		NTSTATUS nt_status = ndr_map_error2ntstatus(ndr_err);
		return replmd_replicated_request_werror(ar, ntstatus_to_werror(nt_status));
	}
	ret = ldb_msg_add_value(msg, "replUpToDateVector", &nuv_value, &nuv_el);
	if (ret != LDB_SUCCESS) {
		return replmd_replicated_request_error(ar, ret);
	}
	nuv_el->flags = LDB_FLAG_MOD_REPLACE;

	/*
	 * now create the new repsFrom value from the given repsFromTo1 structure
	 */
	ZERO_STRUCT(nrf);
	nrf.version					= 1;
	nrf.ctr.ctr1					= *ar->objs->source_dsa;
	/* and fix some values... */
	nrf.ctr.ctr1.consecutive_sync_failures		= 0;
	nrf.ctr.ctr1.last_success			= now;
	nrf.ctr.ctr1.last_attempt			= now;
	nrf.ctr.ctr1.result_last_attempt		= WERR_OK;
	nrf.ctr.ctr1.highwatermark.highest_usn		= nrf.ctr.ctr1.highwatermark.tmp_highest_usn;

	/*
	 * first see if we already have a repsFrom value for the current source dsa
	 * if so we'll later replace this value
	 */
	orf_el = ldb_msg_find_element(ar->search_msg, "repsFrom");
	if (orf_el) {
		for (i=0; i < orf_el->num_values; i++) {
			struct repsFromToBlob *trf;

			trf = talloc(ar, struct repsFromToBlob);
			if (!trf) return replmd_replicated_request_werror(ar, WERR_NOMEM);

			ndr_err = ndr_pull_struct_blob(&orf_el->values[i], trf, trf,
						       (ndr_pull_flags_fn_t)ndr_pull_repsFromToBlob);
			if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
				NTSTATUS nt_status = ndr_map_error2ntstatus(ndr_err);
				return replmd_replicated_request_werror(ar, ntstatus_to_werror(nt_status));
			}

			if (trf->version != 1) {
				return replmd_replicated_request_werror(ar, WERR_DS_DRA_INTERNAL_ERROR);
			}

			/*
			 * we compare the source dsa objectGUID not the invocation_id
			 * because we want only one repsFrom value per source dsa
			 * and when the invocation_id of the source dsa has changed we don't need
			 * the old repsFrom with the old invocation_id
			 */
			if (!GUID_equal(&trf->ctr.ctr1.source_dsa_obj_guid,
					&ar->objs->source_dsa->source_dsa_obj_guid)) {
				talloc_free(trf);
				continue;
			}

			talloc_free(trf);
			nrf_value = &orf_el->values[i];
			break;
		}

		/*
		 * copy over all old values to the new ldb_message
		 */
		ret = ldb_msg_add_empty(msg, "repsFrom", 0, &nrf_el);
		if (ret != LDB_SUCCESS) return replmd_replicated_request_error(ar, ret);
		*nrf_el = *orf_el;
	}

	/*
	 * if we haven't found an old repsFrom value for the current source dsa
	 * we'll add a new value
	 */
	if (!nrf_value) {
		struct ldb_val zero_value;
		ZERO_STRUCT(zero_value);
		ret = ldb_msg_add_value(msg, "repsFrom", &zero_value, &nrf_el);
		if (ret != LDB_SUCCESS) return replmd_replicated_request_error(ar, ret);

		nrf_value = &nrf_el->values[nrf_el->num_values - 1];
	}

	/* we now fill the value which is already attached to ldb_message */
	ndr_err = ndr_push_struct_blob(nrf_value, msg,
				       &nrf,
				       (ndr_push_flags_fn_t)ndr_push_repsFromToBlob);
	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
		NTSTATUS nt_status = ndr_map_error2ntstatus(ndr_err);
		return replmd_replicated_request_werror(ar, ntstatus_to_werror(nt_status));
	}

	/*
	 * the ldb_message_element for the attribute, has all the old values and the new one
	 * so we'll replace the whole attribute with all values
	 */
	nrf_el->flags = LDB_FLAG_MOD_REPLACE;

	if (DEBUGLVL(4)) {
		char *s = ldb_ldif_message_string(ldb, ar, LDB_CHANGETYPE_MODIFY, msg);
		DEBUG(4, ("DRS replication uptodate modify message:\n%s\n", s));
		talloc_free(s);
	}

	/* prepare the ldb_modify() request */
	ret = ldb_build_mod_req(&change_req,
				ldb,
				ar,
				msg,
				ar->controls,
				ar,
				replmd_replicated_uptodate_modify_callback,
				ar->req);
	if (ret != LDB_SUCCESS) return replmd_replicated_request_error(ar, ret);

	return ldb_next_request(ar->module, change_req);
}

static int replmd_replicated_uptodate_search_callback(struct ldb_request *req,
						      struct ldb_reply *ares)
{
	struct replmd_replicated_request *ar = talloc_get_type(req->context,
					       struct replmd_replicated_request);
	int ret;

	if (!ares) {
		return ldb_module_done(ar->req, NULL, NULL,
					LDB_ERR_OPERATIONS_ERROR);
	}
	if (ares->error != LDB_SUCCESS &&
	    ares->error != LDB_ERR_NO_SUCH_OBJECT) {
		return ldb_module_done(ar->req, ares->controls,
					ares->response, ares->error);
	}

	switch (ares->type) {
	case LDB_REPLY_ENTRY:
		ar->search_msg = talloc_steal(ar, ares->message);
		break;

	case LDB_REPLY_REFERRAL:
		/* we ignore referrals */
		break;

	case LDB_REPLY_DONE:
		if (ar->search_msg == NULL) {
			ret = replmd_replicated_request_werror(ar, WERR_DS_DRA_INTERNAL_ERROR);
		} else {
			ret = replmd_replicated_uptodate_modify(ar);
		}
		if (ret != LDB_SUCCESS) {
			return ldb_module_done(ar->req, NULL, NULL, ret);
		}
	}

	talloc_free(ares);
	return LDB_SUCCESS;
}


static int replmd_replicated_uptodate_vector(struct replmd_replicated_request *ar)
{
	struct ldb_context *ldb;
	int ret;
	static const char *attrs[] = {
		"replUpToDateVector",
		"repsFrom",
		NULL
	};
	struct ldb_request *search_req;

	ldb = ldb_module_get_ctx(ar->module);
	ar->search_msg = NULL;

	ret = ldb_build_search_req(&search_req,
				   ldb,
				   ar,
				   ar->objs->partition_dn,
				   LDB_SCOPE_BASE,
				   "(objectClass=*)",
				   attrs,
				   NULL,
				   ar,
				   replmd_replicated_uptodate_search_callback,
				   ar->req);
	if (ret != LDB_SUCCESS) return replmd_replicated_request_error(ar, ret);

	return ldb_next_request(ar->module, search_req);
}



static int replmd_extended_replicated_objects(struct ldb_module *module, struct ldb_request *req)
{
	struct ldb_context *ldb;
	struct dsdb_extended_replicated_objects *objs;
	struct replmd_replicated_request *ar;
	struct ldb_control **ctrls;
	int ret;
	uint32_t i;
	struct replmd_private *replmd_private =
		talloc_get_type(ldb_module_get_private(module), struct replmd_private);

	ldb = ldb_module_get_ctx(module);

	ldb_debug(ldb, LDB_DEBUG_TRACE, "replmd_extended_replicated_objects\n");

	objs = talloc_get_type(req->op.extended.data, struct dsdb_extended_replicated_objects);
	if (!objs) {
		ldb_debug(ldb, LDB_DEBUG_FATAL, "replmd_extended_replicated_objects: invalid extended data\n");
		return LDB_ERR_PROTOCOL_ERROR;
	}

	if (objs->version != DSDB_EXTENDED_REPLICATED_OBJECTS_VERSION) {
		ldb_debug(ldb, LDB_DEBUG_FATAL, "replmd_extended_replicated_objects: extended data invalid version [%u != %u]\n",
			  objs->version, DSDB_EXTENDED_REPLICATED_OBJECTS_VERSION);
		return LDB_ERR_PROTOCOL_ERROR;
	}

	ar = replmd_ctx_init(module, req);
	if (!ar)
		return LDB_ERR_OPERATIONS_ERROR;

	/* Set the flags to have the replmd_op_callback run over the full set of objects */
	ar->apply_mode = true;
	ar->objs = objs;
	ar->schema = dsdb_get_schema(ldb, ar);
	if (!ar->schema) {
		ldb_debug_set(ldb, LDB_DEBUG_FATAL, "replmd_ctx_init: no loaded schema found\n");
		talloc_free(ar);
		DEBUG(0,(__location__ ": %s\n", ldb_errstring(ldb)));
		return LDB_ERR_CONSTRAINT_VIOLATION;
	}

	ctrls = req->controls;

	if (req->controls) {
		req->controls = talloc_memdup(ar, req->controls,
					      talloc_get_size(req->controls));
		if (!req->controls) return replmd_replicated_request_werror(ar, WERR_NOMEM);
	}

	/* This allows layers further down to know if a change came in over replication */
	ret = ldb_request_add_control(req, DSDB_CONTROL_REPLICATED_UPDATE_OID, false, NULL);
	if (ret != LDB_SUCCESS) {
		return ret;
	}

	/* If this change contained linked attributes in the body
	 * (rather than in the links section) we need to update
	 * backlinks in linked_attributes */
	ret = ldb_request_add_control(req, DSDB_CONTROL_APPLY_LINKS, false, NULL);
	if (ret != LDB_SUCCESS) {
		return ret;
	}

	ar->controls = req->controls;
	req->controls = ctrls;

	DEBUG(4,("linked_attributes_count=%u\n", objs->linked_attributes_count));

	/* save away the linked attributes for the end of the
	   transaction */
	for (i=0; i<ar->objs->linked_attributes_count; i++) {
		struct la_entry *la_entry;

		if (replmd_private->la_ctx == NULL) {
			replmd_private->la_ctx = talloc_new(replmd_private);
		}
		la_entry = talloc(replmd_private->la_ctx, struct la_entry);
		if (la_entry == NULL) {
			ldb_oom(ldb);
			return LDB_ERR_OPERATIONS_ERROR;
		}
		la_entry->la = talloc(la_entry, struct drsuapi_DsReplicaLinkedAttribute);
		if (la_entry->la == NULL) {
			talloc_free(la_entry);
			ldb_oom(ldb);
			return LDB_ERR_OPERATIONS_ERROR;
		}
		*la_entry->la = ar->objs->linked_attributes[i];

		/* we need to steal the non-scalars so they stay
		   around until the end of the transaction */
		talloc_steal(la_entry->la, la_entry->la->identifier);
		talloc_steal(la_entry->la, la_entry->la->value.blob);

		DLIST_ADD(replmd_private->la_list, la_entry);
	}

	return replmd_replicated_apply_next(ar);
}

/*
  process one linked attribute structure
 */
static int replmd_process_linked_attribute(struct ldb_module *module,
					   struct la_entry *la_entry)
{
	struct drsuapi_DsReplicaLinkedAttribute *la = la_entry->la;
	struct ldb_context *ldb = ldb_module_get_ctx(module);
	struct ldb_message *msg;
	TALLOC_CTX *tmp_ctx = talloc_new(la_entry);
	const struct dsdb_schema *schema = dsdb_get_schema(ldb, tmp_ctx);
	int ret;
	const struct dsdb_attribute *attr;
	struct dsdb_dn *dsdb_dn;
	uint64_t seq_num = 0;
	struct ldb_message_element *old_el;
	WERROR status;
	time_t t = time(NULL);
	struct ldb_result *res;
	const char *attrs[2];
	struct parsed_dn *pdn_list, *pdn;
	struct GUID guid = GUID_zero();
	NTSTATUS ntstatus;
	bool active = (la->flags & DRSUAPI_DS_LINKED_ATTRIBUTE_FLAG_ACTIVE)?true:false;
	const struct GUID *our_invocation_id;

/*
linked_attributes[0]:
     &objs->linked_attributes[i]: struct drsuapi_DsReplicaLinkedAttribute
        identifier               : *
            identifier: struct drsuapi_DsReplicaObjectIdentifier
                __ndr_size               : 0x0000003a (58)
                __ndr_size_sid           : 0x00000000 (0)
                guid                     : 8e95b6a9-13dd-4158-89db-3220a5be5cc7
                sid                      : S-0-0
                __ndr_size_dn            : 0x00000000 (0)
                dn                       : ''
        attid                    : DRSUAPI_ATTRIBUTE_member (0x1F)
        value: struct drsuapi_DsAttributeValue
            __ndr_size               : 0x0000007e (126)
            blob                     : *
                blob                     : DATA_BLOB length=126
        flags                    : 0x00000001 (1)
               1: DRSUAPI_DS_LINKED_ATTRIBUTE_FLAG_ACTIVE
        originating_add_time     : Wed Sep  2 22:20:01 2009 EST
        meta_data: struct drsuapi_DsReplicaMetaData
            version                  : 0x00000015 (21)
            originating_change_time  : Wed Sep  2 23:39:07 2009 EST
            originating_invocation_id: 794640f3-18cf-40ee-a211-a93992b67a64
            originating_usn          : 0x000000000001e19c (123292)

(for cases where the link is to a normal DN)
     &target: struct drsuapi_DsReplicaObjectIdentifier3
        __ndr_size               : 0x0000007e (126)
        __ndr_size_sid           : 0x0000001c (28)
        guid                     : 7639e594-db75-4086-b0d4-67890ae46031
        sid                      : S-1-5-21-2848215498-2472035911-1947525656-19924
        __ndr_size_dn            : 0x00000022 (34)
        dn                       : 'CN=UOne,OU=TestOU,DC=vsofs8,DC=com'
 */

	/* find the attribute being modified */
	attr = dsdb_attribute_by_attributeID_id(schema, la->attid);
	if (attr == NULL) {
		DEBUG(0, (__location__ ": Unable to find attributeID 0x%x\n", la->attid));
		talloc_free(tmp_ctx);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	attrs[0] = attr->lDAPDisplayName;
	attrs[1] = NULL;

	/* get the existing message from the db for the object with
	   this GUID, returning attribute being modified. We will then
	   use this msg as the basis for a modify call */
	ret = dsdb_module_search(module, tmp_ctx, &res, NULL, LDB_SCOPE_SUBTREE, attrs,
	                         DSDB_FLAG_NEXT_MODULE |
				 DSDB_SEARCH_SEARCH_ALL_PARTITIONS |
				 DSDB_SEARCH_SHOW_DELETED |
				 DSDB_SEARCH_SHOW_DN_IN_STORAGE_FORMAT |
				 DSDB_SEARCH_REVEAL_INTERNALS,
				 "objectGUID=%s", GUID_string(tmp_ctx, &la->identifier->guid));
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}
	if (res->count != 1) {
		ldb_asprintf_errstring(ldb, "DRS linked attribute for GUID %s - DN not found",
				       GUID_string(tmp_ctx, &la->identifier->guid));
		talloc_free(tmp_ctx);
		return LDB_ERR_NO_SUCH_OBJECT;
	}
	msg = res->msgs[0];

	if (msg->num_elements == 0) {
		ret = ldb_msg_add_empty(msg, attr->lDAPDisplayName, LDB_FLAG_MOD_REPLACE, &old_el);
		if (ret != LDB_SUCCESS) {
			ldb_module_oom(module);
			talloc_free(tmp_ctx);
			return LDB_ERR_OPERATIONS_ERROR;
		}
	} else {
		old_el = &msg->elements[0];
		old_el->flags = LDB_FLAG_MOD_REPLACE;
	}

	/* parse the existing links */
	ret = get_parsed_dns(module, tmp_ctx, old_el, &pdn_list, attr->syntax->ldap_oid);
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}

	/* get our invocationId */
	our_invocation_id = samdb_ntds_invocation_id(ldb);
	if (!our_invocation_id) {
		ldb_debug_set(ldb, LDB_DEBUG_ERROR, __location__ ": unable to find invocationId\n");
		talloc_free(tmp_ctx);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	ret = replmd_check_upgrade_links(pdn_list, old_el->num_values, old_el, our_invocation_id);
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}

	status = dsdb_dn_la_from_blob(ldb, attr, schema, tmp_ctx, la->value.blob, &dsdb_dn);
	if (!W_ERROR_IS_OK(status)) {
		ldb_asprintf_errstring(ldb, "Failed to parsed linked attribute blob for %s on %s - %s\n",
				       old_el->name, ldb_dn_get_linearized(msg->dn), win_errstr(status));
		return LDB_ERR_OPERATIONS_ERROR;
	}

	ntstatus = dsdb_get_extended_dn_guid(dsdb_dn->dn, &guid, "GUID");
	if (!NT_STATUS_IS_OK(ntstatus) && active) {
		ldb_asprintf_errstring(ldb, "Failed to find GUID in linked attribute blob for %s on %s from %s",
				       old_el->name,
				       ldb_dn_get_linearized(dsdb_dn->dn),
				       ldb_dn_get_linearized(msg->dn));
		return LDB_ERR_OPERATIONS_ERROR;
	}

	/* re-resolve the DN by GUID, as the DRS server may give us an
	   old DN value */
	ret = dsdb_module_dn_by_guid(module, dsdb_dn, &guid, &dsdb_dn->dn);
	if (ret != LDB_SUCCESS) {
		DEBUG(2,(__location__ ": WARNING: Failed to re-resolve GUID %s - using %s",
			 GUID_string(tmp_ctx, &guid),
			 ldb_dn_get_linearized(dsdb_dn->dn)));
	}

	/* see if this link already exists */
	pdn = parsed_dn_find(pdn_list, old_el->num_values, &guid, dsdb_dn->dn);
	if (pdn != NULL) {
		/* see if this update is newer than what we have already */
		struct GUID invocation_id = GUID_zero();
		uint32_t version = 0;
		NTTIME change_time = 0;
		uint32_t rmd_flags = dsdb_dn_rmd_flags(pdn->dsdb_dn->dn);

		dsdb_get_extended_dn_guid(pdn->dsdb_dn->dn, &invocation_id, "RMD_INVOCID");
		dsdb_get_extended_dn_uint32(pdn->dsdb_dn->dn, &version, "RMD_VERSION");
		dsdb_get_extended_dn_nttime(pdn->dsdb_dn->dn, &change_time, "RMD_CHANGETIME");

		if (!replmd_update_is_newer(&invocation_id,
					    &la->meta_data.originating_invocation_id,
					    version,
					    la->meta_data.version,
					    change_time,
					    la->meta_data.originating_change_time)) {
			DEBUG(3,("Discarding older DRS linked attribute update to %s on %s from %s\n",
				 old_el->name, ldb_dn_get_linearized(msg->dn),
				 GUID_string(tmp_ctx, &la->meta_data.originating_invocation_id)));
			talloc_free(tmp_ctx);
			return LDB_SUCCESS;
		}

		/* get a seq_num for this change */
		ret = ldb_sequence_number(ldb, LDB_SEQ_NEXT, &seq_num);
		if (ret != LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			return ret;
		}

		if (!(rmd_flags & DSDB_RMD_FLAG_DELETED)) {
			/* remove the existing backlink */
			ret = replmd_add_backlink(module, schema, &la->identifier->guid, &guid, false, attr, false);
			if (ret != LDB_SUCCESS) {
				talloc_free(tmp_ctx);
				return ret;
			}
		}

		ret = replmd_update_la_val(tmp_ctx, pdn->v, dsdb_dn, pdn->dsdb_dn,
					   &la->meta_data.originating_invocation_id,
					   la->meta_data.originating_usn, seq_num,
					   la->meta_data.originating_change_time,
					   la->meta_data.version,
					   !active);
		if (ret != LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			return ret;
		}

		if (active) {
			/* add the new backlink */
			ret = replmd_add_backlink(module, schema, &la->identifier->guid, &guid, true, attr, false);
			if (ret != LDB_SUCCESS) {
				talloc_free(tmp_ctx);
				return ret;
			}
		}
	} else {
		/* get a seq_num for this change */
		ret = ldb_sequence_number(ldb, LDB_SEQ_NEXT, &seq_num);
		if (ret != LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			return ret;
		}

		old_el->values = talloc_realloc(msg->elements, old_el->values,
						struct ldb_val, old_el->num_values+1);
		if (!old_el->values) {
			ldb_module_oom(module);
			return LDB_ERR_OPERATIONS_ERROR;
		}
		old_el->num_values++;

		ret = replmd_build_la_val(tmp_ctx, &old_el->values[old_el->num_values-1], dsdb_dn,
					  &la->meta_data.originating_invocation_id,
					  la->meta_data.originating_usn, seq_num,
					  la->meta_data.originating_change_time,
					  la->meta_data.version,
					  (la->flags & DRSUAPI_DS_LINKED_ATTRIBUTE_FLAG_ACTIVE)?false:true);
		if (ret != LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			return ret;
		}

		if (active) {
			ret = replmd_add_backlink(module, schema, &la->identifier->guid, &guid,
						  true, attr, false);
			if (ret != LDB_SUCCESS) {
				talloc_free(tmp_ctx);
				return ret;
			}
		}
	}

	/* we only change whenChanged and uSNChanged if the seq_num
	   has changed */
	if (add_time_element(msg, "whenChanged", t) != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	if (add_uint64_element(msg, "uSNChanged", seq_num) != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return LDB_ERR_OPERATIONS_ERROR;
	}

	ret = dsdb_check_single_valued_link(attr, old_el);
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ret;
	}

	ret = dsdb_module_modify(module, msg, DSDB_FLAG_NEXT_MODULE | DSDB_MODIFY_RELAX);
	if (ret != LDB_SUCCESS) {
		ldb_debug(ldb, LDB_DEBUG_WARNING, "Failed to apply linked attribute change '%s'\n%s\n",
			  ldb_errstring(ldb),
			  ldb_ldif_message_string(ldb, tmp_ctx, LDB_CHANGETYPE_MODIFY, msg));
		talloc_free(tmp_ctx);
		return ret;
	}

	talloc_free(tmp_ctx);

	return ret;
}

static int replmd_extended(struct ldb_module *module, struct ldb_request *req)
{
	if (strcmp(req->op.extended.oid, DSDB_EXTENDED_REPLICATED_OBJECTS_OID) == 0) {
		return replmd_extended_replicated_objects(module, req);
	}

	return ldb_next_request(module, req);
}


/*
  we hook into the transaction operations to allow us to
  perform the linked attribute updates at the end of the whole
  transaction. This allows a forward linked attribute to be created
  before the object is created. During a vampire, w2k8 sends us linked
  attributes before the objects they are part of.
 */
static int replmd_start_transaction(struct ldb_module *module)
{
	/* create our private structure for this transaction */
	struct replmd_private *replmd_private = talloc_get_type(ldb_module_get_private(module),
								struct replmd_private);
	replmd_txn_cleanup(replmd_private);

	/* free any leftover mod_usn records from cancelled
	   transactions */
	while (replmd_private->ncs) {
		struct nc_entry *e = replmd_private->ncs;
		DLIST_REMOVE(replmd_private->ncs, e);
		talloc_free(e);
	}

	return ldb_next_start_trans(module);
}

/*
  on prepare commit we loop over our queued la_context structures and
  apply each of them
 */
static int replmd_prepare_commit(struct ldb_module *module)
{
	struct replmd_private *replmd_private =
		talloc_get_type(ldb_module_get_private(module), struct replmd_private);
	struct la_entry *la, *prev;
	struct la_backlink *bl;
	int ret;

	/* walk the list backwards, to do the first entry first, as we
	 * added the entries with DLIST_ADD() which puts them at the
	 * start of the list */
	for (la = DLIST_TAIL(replmd_private->la_list); la; la=prev) {
		prev = DLIST_PREV(la);
		DLIST_REMOVE(replmd_private->la_list, la);
		ret = replmd_process_linked_attribute(module, la);
		if (ret != LDB_SUCCESS) {
			replmd_txn_cleanup(replmd_private);
			return ret;
		}
	}

	/* process our backlink list, creating and deleting backlinks
	   as necessary */
	for (bl=replmd_private->la_backlinks; bl; bl=bl->next) {
		ret = replmd_process_backlink(module, bl);
		if (ret != LDB_SUCCESS) {
			replmd_txn_cleanup(replmd_private);
			return ret;
		}
	}

	replmd_txn_cleanup(replmd_private);

	/* possibly change @REPLCHANGED */
	ret = replmd_notify_store(module);
	if (ret != LDB_SUCCESS) {
		return ret;
	}

	return ldb_next_prepare_commit(module);
}

static int replmd_del_transaction(struct ldb_module *module)
{
	struct replmd_private *replmd_private =
		talloc_get_type(ldb_module_get_private(module), struct replmd_private);
	replmd_txn_cleanup(replmd_private);

	return ldb_next_del_trans(module);
}


_PUBLIC_ const struct ldb_module_ops ldb_repl_meta_data_module_ops = {
	.name          = "repl_meta_data",
	.init_context	   = replmd_init,
	.add               = replmd_add,
	.modify            = replmd_modify,
	.rename            = replmd_rename,
	.del	           = replmd_delete,
	.extended          = replmd_extended,
	.start_transaction = replmd_start_transaction,
	.prepare_commit    = replmd_prepare_commit,
	.del_transaction   = replmd_del_transaction,
};