summaryrefslogtreecommitdiffstats
path: root/lib/vty.c
blob: ed8b71ed22d548d04ab5ba53cf4fef3504172789 (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
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Virtual terminal [aka TeletYpe] interface routine.
 * Copyright (C) 1997, 98 Kunihiro Ishiguro
 */

#include <zebra.h>

#include <lib/version.h>
#include <sys/types.h>
#include <sys/types.h>
#ifdef HAVE_LIBPCRE2_POSIX
#ifndef _FRR_PCRE2_POSIX
#define _FRR_PCRE2_POSIX
#include <pcre2posix.h>
#endif /* _FRR_PCRE2_POSIX */
#elif defined(HAVE_LIBPCREPOSIX)
#include <pcreposix.h>
#else
#include <regex.h>
#endif /* HAVE_LIBPCRE2_POSIX */
#include <stdio.h>

#include "debug.h"
#include "linklist.h"
#include "frrevent.h"
#include "buffer.h"
#include "command.h"
#include "sockunion.h"
#include "memory.h"
#include "log.h"
#include "prefix.h"
#include "filter.h"
#include "vty.h"
#include "privs.h"
#include "network.h"
#include "libfrr.h"
#include "frrstr.h"
#include "lib_errors.h"
#include "northbound_cli.h"
#include "printfrr.h"
#include "json.h"

#include <arpa/telnet.h>
#include <termios.h>

#include "lib/vty_clippy.c"

DEFINE_MTYPE_STATIC(LIB, VTY, "VTY");
DEFINE_MTYPE_STATIC(LIB, VTY_SERV, "VTY server");
DEFINE_MTYPE_STATIC(LIB, VTY_OUT_BUF, "VTY output buffer");
DEFINE_MTYPE_STATIC(LIB, VTY_HIST, "VTY history");

DECLARE_DLIST(vtys, struct vty, itm);

/* Vty events */
enum vty_event {
	VTY_SERV,
	VTY_READ,
	VTY_WRITE,
	VTY_TIMEOUT_RESET,
#ifdef VTYSH
	VTYSH_SERV,
	VTYSH_READ,
	VTYSH_WRITE
#endif /* VTYSH */
};

struct nb_config *vty_mgmt_candidate_config;

static struct mgmt_fe_client *mgmt_fe_client;
static bool mgmt_fe_connected;
static uint64_t mgmt_client_id_next;
static uint64_t mgmt_last_req_id = UINT64_MAX;

PREDECL_DLIST(vtyservs);

struct vty_serv {
	struct vtyservs_item itm;

	int sock;
	bool vtysh;

	struct event *t_accept;
};

DECLARE_DLIST(vtyservs, struct vty_serv, itm);

static void vty_event_serv(enum vty_event event, struct vty_serv *);
static void vty_event(enum vty_event, struct vty *);
static int vtysh_flush(struct vty *vty);

/* Extern host structure from command.c */
extern struct host host;

/* active listeners */
static struct vtyservs_head vty_servs[1] = {INIT_DLIST(vty_servs[0])};

/* active connections */
static struct vtys_head vty_sessions[1] = {INIT_DLIST(vty_sessions[0])};
static struct vtys_head vtysh_sessions[1] = {INIT_DLIST(vtysh_sessions[0])};

/* Vty timeout value. */
static unsigned long vty_timeout_val = VTY_TIMEOUT_DEFAULT;

/* Vty access-class command */
static char *vty_accesslist_name = NULL;

/* Vty access-calss for IPv6. */
static char *vty_ipv6_accesslist_name = NULL;

/* Current directory. */
static char vty_cwd[MAXPATHLEN];

/* Login password check. */
static int no_password_check = 0;

/* Integrated configuration file path */
static char integrate_default[] = SYSCONFDIR INTEGRATE_DEFAULT_CONFIG;

bool vty_log_commands;
static bool vty_log_commands_perm;

char const *const mgmt_daemons[] = {
#ifdef HAVE_STATICD
	"staticd",
#endif
};
uint mgmt_daemons_count = array_size(mgmt_daemons);


static int vty_mgmt_lock_candidate_inline(struct vty *vty)
{
	assert(!vty->mgmt_locked_candidate_ds);
	(void)vty_mgmt_send_lockds_req(vty, MGMTD_DS_CANDIDATE, true, true);
	return vty->mgmt_locked_candidate_ds ? 0 : -1;
}

static int vty_mgmt_unlock_candidate_inline(struct vty *vty)
{
	assert(vty->mgmt_locked_candidate_ds);
	(void)vty_mgmt_send_lockds_req(vty, MGMTD_DS_CANDIDATE, false, true);
	return vty->mgmt_locked_candidate_ds ? -1 : 0;
}

static int vty_mgmt_lock_running_inline(struct vty *vty)
{
	assert(!vty->mgmt_locked_running_ds);
	(void)vty_mgmt_send_lockds_req(vty, MGMTD_DS_RUNNING, true, true);
	return vty->mgmt_locked_running_ds ? 0 : -1;
}

static int vty_mgmt_unlock_running_inline(struct vty *vty)
{
	assert(vty->mgmt_locked_running_ds);
	(void)vty_mgmt_send_lockds_req(vty, MGMTD_DS_RUNNING, false, true);
	return vty->mgmt_locked_running_ds ? -1 : 0;
}

void vty_mgmt_resume_response(struct vty *vty, bool success)
{
	uint8_t header[4] = {0, 0, 0, 0};
	int ret = CMD_SUCCESS;

	if (!vty->mgmt_req_pending_cmd) {
		zlog_err(
			"vty resume response called without mgmt_req_pending_cmd");
		return;
	}

	if (!success)
		ret = CMD_WARNING_CONFIG_FAILED;

	MGMTD_FE_CLIENT_DBG(
		"resuming CLI cmd after %s on vty session-id: %" PRIu64
		" with '%s'",
		vty->mgmt_req_pending_cmd, vty->mgmt_session_id,
		success ? "succeeded" : "failed");

	vty->mgmt_req_pending_cmd = NULL;

	if (vty->type != VTY_FILE) {
		header[3] = ret;
		buffer_put(vty->obuf, header, 4);
		if (!vty->t_write && (vtysh_flush(vty) < 0)) {
			zlog_err("failed to vtysh_flush");
			/* Try to flush results; exit if a write error occurs */
			return;
		}
	}

	if (vty->status == VTY_CLOSE)
		vty_close(vty);
	else if (vty->type != VTY_FILE)
		vty_event(VTYSH_READ, vty);
	else
		/* should we assert here? */
		zlog_err("mgmtd: unexpected resume while reading config file");
}

void vty_frame(struct vty *vty, const char *format, ...)
{
	va_list args;

	va_start(args, format);
	vsnprintfrr(vty->frame + vty->frame_pos,
		    sizeof(vty->frame) - vty->frame_pos, format, args);
	vty->frame_pos = strlen(vty->frame);
	va_end(args);
}

void vty_endframe(struct vty *vty, const char *endtext)
{
	if (vty->frame_pos == 0 && endtext)
		vty_out(vty, "%s", endtext);
	vty->frame_pos = 0;
}

bool vty_set_include(struct vty *vty, const char *regexp)
{
	int errcode;
	bool ret = true;
	char errbuf[256];

	if (!regexp) {
		if (vty->filter) {
			regfree(&vty->include);
			vty->filter = false;
		}
		return true;
	}

	errcode = regcomp(&vty->include, regexp,
			  REG_EXTENDED | REG_NEWLINE | REG_NOSUB);
	if (errcode) {
		ret = false;
		regerror(errcode, &vty->include, errbuf, sizeof(errbuf));
		vty_out(vty, "%% Regex compilation error: %s\n", errbuf);
	} else {
		vty->filter = true;
	}

	return ret;
}

/* VTY standard output function. */
int vty_out(struct vty *vty, const char *format, ...)
{
	va_list args;
	ssize_t len;
	char buf[1024];
	char *p = NULL;
	char *filtered;
	/* format string may contain %m, keep errno intact for printfrr */
	int saved_errno = errno;

	if (vty->frame_pos) {
		vty->frame_pos = 0;
		vty_out(vty, "%s", vty->frame);
	}

	va_start(args, format);
	errno = saved_errno;
	p = vasnprintfrr(MTYPE_VTY_OUT_BUF, buf, sizeof(buf), format, args);
	va_end(args);

	len = strlen(p);

	/* filter buffer */
	if (vty->filter) {
		vector lines = frrstr_split_vec(p, "\n");

		/* Place first value in the cache */
		char *firstline = vector_slot(lines, 0);
		buffer_put(vty->lbuf, (uint8_t *) firstline, strlen(firstline));

		/* If our split returned more than one entry, time to filter */
		if (vector_active(lines) > 1) {
			/*
			 * returned string is MTYPE_TMP so it matches the MTYPE
			 * of everything else in the vector
			 */
			char *bstr = buffer_getstr(vty->lbuf);
			buffer_reset(vty->lbuf);
			XFREE(MTYPE_TMP, lines->index[0]);
			vector_set_index(lines, 0, bstr);
			frrstr_filter_vec(lines, &vty->include);
			vector_compact(lines);
			/*
			 * Consider the string "foo\n". If the regex is an empty string
			 * and the line ended with a newline, then the vector will look
			 * like:
			 *
			 * [0]: 'foo'
			 * [1]: ''
			 *
			 * If the regex isn't empty, the vector will look like:
			 *
			 * [0]: 'foo'
			 *
			 * In this case we'd like to preserve the newline, so we add
			 * the empty string [1] as in the first example.
			 */
			if (p[strlen(p) - 1] == '\n' && vector_active(lines) > 0
			    && strlen(vector_slot(lines, vector_active(lines) - 1)))
				vector_set(lines, XSTRDUP(MTYPE_TMP, ""));

			filtered = frrstr_join_vec(lines, "\n");
		}
		else {
			filtered = NULL;
		}

		frrstr_strvec_free(lines);

	} else {
		filtered = p;
	}

	if (!filtered)
		goto done;

	switch (vty->type) {
	case VTY_TERM:
		/* print with crlf replacement */
		buffer_put_crlf(vty->obuf, (uint8_t *)filtered,
				strlen(filtered));
		break;
	case VTY_SHELL:
		if (vty->of) {
			fprintf(vty->of, "%s", filtered);
			fflush(vty->of);
		} else if (vty->of_saved) {
			fprintf(vty->of_saved, "%s", filtered);
			fflush(vty->of_saved);
		}
		break;
	case VTY_SHELL_SERV:
	case VTY_FILE:
	default:
		/* print without crlf replacement */
		buffer_put(vty->obuf, (uint8_t *)filtered, strlen(filtered));
		break;
	}

done:

	if (vty->filter && filtered)
		XFREE(MTYPE_TMP, filtered);

	/* If p is not different with buf, it is allocated buffer.  */
	if (p != buf)
		XFREE(MTYPE_VTY_OUT_BUF, p);

	return len;
}

static int vty_json_helper(struct vty *vty, struct json_object *json,
			   uint32_t options)
{
	const char *text;

	if (!json)
		return CMD_SUCCESS;

	text = json_object_to_json_string_ext(
		json, options);
	vty_out(vty, "%s\n", text);
	json_object_free(json);

	return CMD_SUCCESS;
}

int vty_json(struct vty *vty, struct json_object *json)
{
	return vty_json_helper(vty, json,
			       JSON_C_TO_STRING_PRETTY |
				       JSON_C_TO_STRING_NOSLASHESCAPE);
}

int vty_json_no_pretty(struct vty *vty, struct json_object *json)
{
	return vty_json_helper(vty, json, JSON_C_TO_STRING_NOSLASHESCAPE);
}

void vty_json_empty(struct vty *vty)
{
	json_object *json = json_object_new_object();

	vty_json(vty, json);
}

/* Output current time to the vty. */
void vty_time_print(struct vty *vty, int cr)
{
	char buf[FRR_TIMESTAMP_LEN];

	if (frr_timestamp(0, buf, sizeof(buf)) == 0) {
		zlog_info("frr_timestamp error");
		return;
	}
	if (cr)
		vty_out(vty, "%s\n", buf);
	else
		vty_out(vty, "%s ", buf);

	return;
}

/* Say hello to vty interface. */
void vty_hello(struct vty *vty)
{
	if (host.motdfile) {
		FILE *f;
		char buf[4096];

		f = fopen(host.motdfile, "r");
		if (f) {
			while (fgets(buf, sizeof(buf), f)) {
				char *s;
				/* work backwards to ignore trailling isspace()
				 */
				for (s = buf + strlen(buf);
				     (s > buf) && isspace((unsigned char)s[-1]);
				     s--)
					;
				*s = '\0';
				vty_out(vty, "%s\n", buf);
			}
			fclose(f);
		} else
			vty_out(vty, "MOTD file not found\n");
	} else if (host.motd)
		vty_out(vty, "%s", host.motd);
}

#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wformat-nonliteral"
/* prompt formatting has a %s in the cmd_node prompt string.
 *
 * Also for some reason GCC emits the warning on the end of the function
 * (optimization maybe?) rather than on the vty_out line, so this pragma
 * wraps the entire function rather than just the vty_out line.
 */

/* Put out prompt and wait input from user. */
static void vty_prompt(struct vty *vty)
{
	if (vty->type == VTY_TERM) {
		vty_out(vty, cmd_prompt(vty->node), cmd_hostname_get());
	}
}
#pragma GCC diagnostic pop

/* Send WILL TELOPT_ECHO to remote server. */
static void vty_will_echo(struct vty *vty)
{
	unsigned char cmd[] = {IAC, WILL, TELOPT_ECHO, '\0'};
	vty_out(vty, "%s", cmd);
}

/* Make suppress Go-Ahead telnet option. */
static void vty_will_suppress_go_ahead(struct vty *vty)
{
	unsigned char cmd[] = {IAC, WILL, TELOPT_SGA, '\0'};
	vty_out(vty, "%s", cmd);
}

/* Make don't use linemode over telnet. */
static void vty_dont_linemode(struct vty *vty)
{
	unsigned char cmd[] = {IAC, DONT, TELOPT_LINEMODE, '\0'};
	vty_out(vty, "%s", cmd);
}

/* Use window size. */
static void vty_do_window_size(struct vty *vty)
{
	unsigned char cmd[] = {IAC, DO, TELOPT_NAWS, '\0'};
	vty_out(vty, "%s", cmd);
}

/* Authentication of vty */
static void vty_auth(struct vty *vty, char *buf)
{
	char *passwd = NULL;
	enum node_type next_node = 0;
	int fail;

	switch (vty->node) {
	case AUTH_NODE:
		if (host.encrypt)
			passwd = host.password_encrypt;
		else
			passwd = host.password;
		if (host.advanced)
			next_node = host.enable ? VIEW_NODE : ENABLE_NODE;
		else
			next_node = VIEW_NODE;
		break;
	case AUTH_ENABLE_NODE:
		if (host.encrypt)
			passwd = host.enable_encrypt;
		else
			passwd = host.enable;
		next_node = ENABLE_NODE;
		break;
	}

	if (passwd) {
		if (host.encrypt)
			fail = strcmp(crypt(buf, passwd), passwd);
		else
			fail = strcmp(buf, passwd);
	} else
		fail = 1;

	if (!fail) {
		vty->fail = 0;
		vty->node = next_node; /* Success ! */
	} else {
		vty->fail++;
		if (vty->fail >= 3) {
			if (vty->node == AUTH_NODE) {
				vty_out(vty,
					"%% Bad passwords, too many failures!\n");
				vty->status = VTY_CLOSE;
			} else {
				/* AUTH_ENABLE_NODE */
				vty->fail = 0;
				vty_out(vty,
					"%% Bad enable passwords, too many failures!\n");
				vty->status = VTY_CLOSE;
			}
		}
	}
}

/* Command execution over the vty interface. */
static int vty_command(struct vty *vty, char *buf)
{
	int ret;
	const char *protocolname;
	char *cp = NULL;

	assert(vty);

	/*
	 * Log non empty command lines
	 */
	if (vty_log_commands &&
	    strncmp(buf, "echo PING", strlen("echo PING")) != 0)
		cp = buf;
	if (cp != NULL) {
		/* Skip white spaces. */
		while (isspace((unsigned char)*cp) && *cp != '\0')
			cp++;
	}
	if (cp != NULL && *cp != '\0') {
		char vty_str[VTY_BUFSIZ];
		char prompt_str[VTY_BUFSIZ];

		/* format the base vty info */
		snprintf(vty_str, sizeof(vty_str), "vty[%d]@%s", vty->fd,
			 vty->address);

		/* format the prompt */
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wformat-nonliteral"
		/* prompt formatting has a %s in the cmd_node prompt string */
		snprintf(prompt_str, sizeof(prompt_str), cmd_prompt(vty->node),
			 vty_str);
#pragma GCC diagnostic pop

		/* now log the command */
		zlog_notice("%s%s", prompt_str, buf);
	}

	RUSAGE_T before;
	RUSAGE_T after;
	unsigned long walltime, cputime;

	/* cmd_execute() may change cputime_enabled if we're executing the
	 * "service cputime-stats" command, which can result in nonsensical
	 * and very confusing warnings
	 */
	bool cputime_enabled_here = cputime_enabled;

	GETRUSAGE(&before);

	ret = cmd_execute(vty, buf, NULL, 0);

	GETRUSAGE(&after);

	walltime = event_consumed_time(&after, &before, &cputime);

	if (cputime_enabled_here && cputime_enabled && cputime_threshold
	    && cputime > cputime_threshold)
		/* Warn about CPU hog that must be fixed. */
		flog_warn(EC_LIB_SLOW_THREAD_CPU,
			  "CPU HOG: command took %lums (cpu time %lums): %s",
			  walltime / 1000, cputime / 1000, buf);
	else if (walltime_threshold && walltime > walltime_threshold)
		flog_warn(EC_LIB_SLOW_THREAD_WALL,
			  "STARVATION: command took %lums (cpu time %lums): %s",
			  walltime / 1000, cputime / 1000, buf);

	/* Get the name of the protocol if any */
	protocolname = frr_protoname;

	if (ret != CMD_SUCCESS)
		switch (ret) {
		case CMD_WARNING:
			if (vty->type == VTY_FILE)
				vty_out(vty, "Warning...\n");
			break;
		case CMD_ERR_AMBIGUOUS:
			vty_out(vty, "%% Ambiguous command.\n");
			break;
		case CMD_ERR_NO_MATCH:
			vty_out(vty, "%% [%s] Unknown command: %s\n",
				protocolname, buf);
			break;
		case CMD_ERR_INCOMPLETE:
			vty_out(vty, "%% Command incomplete.\n");
			break;
		}

	return ret;
}

static const char telnet_backward_char = 0x08;
static const char telnet_space_char = ' ';

/* Basic function to write buffer to vty. */
static void vty_write(struct vty *vty, const char *buf, size_t nbytes)
{
	if ((vty->node == AUTH_NODE) || (vty->node == AUTH_ENABLE_NODE))
		return;

	/* Should we do buffering here ?  And make vty_flush (vty) ? */
	buffer_put(vty->obuf, buf, nbytes);
}

/* Basic function to insert character into vty. */
static void vty_self_insert(struct vty *vty, char c)
{
	int i;
	int length;

	if (vty->length + 1 >= VTY_BUFSIZ)
		return;

	length = vty->length - vty->cp;
	memmove(&vty->buf[vty->cp + 1], &vty->buf[vty->cp], length);
	vty->buf[vty->cp] = c;

	vty_write(vty, &vty->buf[vty->cp], length + 1);
	for (i = 0; i < length; i++)
		vty_write(vty, &telnet_backward_char, 1);

	vty->cp++;
	vty->length++;

	vty->buf[vty->length] = '\0';
}

/* Self insert character 'c' in overwrite mode. */
static void vty_self_insert_overwrite(struct vty *vty, char c)
{
	if (vty->cp == vty->length) {
		vty_self_insert(vty, c);
		return;
	}

	vty->buf[vty->cp++] = c;
	vty_write(vty, &c, 1);
}

/**
 * Insert a string into vty->buf at the current cursor position.
 *
 * If the resultant string would be larger than VTY_BUFSIZ it is
 * truncated to fit.
 */
static void vty_insert_word_overwrite(struct vty *vty, char *str)
{
	if (vty->cp == VTY_BUFSIZ)
		return;

	size_t nwrite = MIN((int)strlen(str), VTY_BUFSIZ - vty->cp - 1);
	memcpy(&vty->buf[vty->cp], str, nwrite);
	vty->cp += nwrite;
	vty->length = MAX(vty->cp, vty->length);
	vty->buf[vty->length] = '\0';
	vty_write(vty, str, nwrite);
}

/* Forward character. */
static void vty_forward_char(struct vty *vty)
{
	if (vty->cp < vty->length) {
		vty_write(vty, &vty->buf[vty->cp], 1);
		vty->cp++;
	}
}

/* Backward character. */
static void vty_backward_char(struct vty *vty)
{
	if (vty->cp > 0) {
		vty->cp--;
		vty_write(vty, &telnet_backward_char, 1);
	}
}

/* Move to the beginning of the line. */
static void vty_beginning_of_line(struct vty *vty)
{
	while (vty->cp)
		vty_backward_char(vty);
}

/* Move to the end of the line. */
static void vty_end_of_line(struct vty *vty)
{
	while (vty->cp < vty->length)
		vty_forward_char(vty);
}

static void vty_kill_line_from_beginning(struct vty *);
static void vty_redraw_line(struct vty *);

/* Print command line history.  This function is called from
   vty_next_line and vty_previous_line. */
static void vty_history_print(struct vty *vty)
{
	int length;

	vty_kill_line_from_beginning(vty);

	/* Get previous line from history buffer */
	length = strlen(vty->hist[vty->hp]);
	memcpy(vty->buf, vty->hist[vty->hp], length);
	vty->cp = vty->length = length;
	vty->buf[vty->length] = '\0';

	/* Redraw current line */
	vty_redraw_line(vty);
}

/* Show next command line history. */
static void vty_next_line(struct vty *vty)
{
	int try_index;

	if (vty->hp == vty->hindex)
		return;

	/* Try is there history exist or not. */
	try_index = vty->hp;
	if (try_index == (VTY_MAXHIST - 1))
		try_index = 0;
	else
		try_index++;

	/* If there is not history return. */
	if (vty->hist[try_index] == NULL)
		return;
	else
		vty->hp = try_index;

	vty_history_print(vty);
}

/* Show previous command line history. */
static void vty_previous_line(struct vty *vty)
{
	int try_index;

	try_index = vty->hp;
	if (try_index == 0)
		try_index = VTY_MAXHIST - 1;
	else
		try_index--;

	if (vty->hist[try_index] == NULL)
		return;
	else
		vty->hp = try_index;

	vty_history_print(vty);
}

/* This function redraw all of the command line character. */
static void vty_redraw_line(struct vty *vty)
{
	vty_write(vty, vty->buf, vty->length);
	vty->cp = vty->length;
}

/* Forward word. */
static void vty_forward_word(struct vty *vty)
{
	while (vty->cp != vty->length && vty->buf[vty->cp] != ' ')
		vty_forward_char(vty);

	while (vty->cp != vty->length && vty->buf[vty->cp] == ' ')
		vty_forward_char(vty);
}

/* Backward word without skipping training space. */
static void vty_backward_pure_word(struct vty *vty)
{
	while (vty->cp > 0 && vty->buf[vty->cp - 1] != ' ')
		vty_backward_char(vty);
}

/* Backward word. */
static void vty_backward_word(struct vty *vty)
{
	while (vty->cp > 0 && vty->buf[vty->cp - 1] == ' ')
		vty_backward_char(vty);

	while (vty->cp > 0 && vty->buf[vty->cp - 1] != ' ')
		vty_backward_char(vty);
}

/* When '^D' is typed at the beginning of the line we move to the down
   level. */
static void vty_down_level(struct vty *vty)
{
	vty_out(vty, "\n");
	cmd_exit(vty);
	vty_prompt(vty);
	vty->cp = 0;
}

/* When '^Z' is received from vty, move down to the enable mode. */
static void vty_end_config(struct vty *vty)
{
	vty_out(vty, "\n");

	if (vty->config) {
		vty_config_exit(vty);
		vty->node = ENABLE_NODE;
	}

	vty_prompt(vty);
	vty->cp = 0;
}

/* Delete a character at the current point. */
static void vty_delete_char(struct vty *vty)
{
	int i;
	int size;

	if (vty->length == 0) {
		vty_down_level(vty);
		return;
	}

	if (vty->cp == vty->length)
		return; /* completion need here? */

	size = vty->length - vty->cp;

	vty->length--;
	memmove(&vty->buf[vty->cp], &vty->buf[vty->cp + 1], size - 1);
	vty->buf[vty->length] = '\0';

	if (vty->node == AUTH_NODE || vty->node == AUTH_ENABLE_NODE)
		return;

	vty_write(vty, &vty->buf[vty->cp], size - 1);
	vty_write(vty, &telnet_space_char, 1);

	for (i = 0; i < size; i++)
		vty_write(vty, &telnet_backward_char, 1);
}

/* Delete a character before the point. */
static void vty_delete_backward_char(struct vty *vty)
{
	if (vty->cp == 0)
		return;

	vty_backward_char(vty);
	vty_delete_char(vty);
}

/* Kill rest of line from current point. */
static void vty_kill_line(struct vty *vty)
{
	int i;
	int size;

	size = vty->length - vty->cp;

	if (size == 0)
		return;

	for (i = 0; i < size; i++)
		vty_write(vty, &telnet_space_char, 1);
	for (i = 0; i < size; i++)
		vty_write(vty, &telnet_backward_char, 1);

	memset(&vty->buf[vty->cp], 0, size);
	vty->length = vty->cp;
}

/* Kill line from the beginning. */
static void vty_kill_line_from_beginning(struct vty *vty)
{
	vty_beginning_of_line(vty);
	vty_kill_line(vty);
}

/* Delete a word before the point. */
static void vty_forward_kill_word(struct vty *vty)
{
	while (vty->cp != vty->length && vty->buf[vty->cp] == ' ')
		vty_delete_char(vty);
	while (vty->cp != vty->length && vty->buf[vty->cp] != ' ')
		vty_delete_char(vty);
}

/* Delete a word before the point. */
static void vty_backward_kill_word(struct vty *vty)
{
	while (vty->cp > 0 && vty->buf[vty->cp - 1] == ' ')
		vty_delete_backward_char(vty);
	while (vty->cp > 0 && vty->buf[vty->cp - 1] != ' ')
		vty_delete_backward_char(vty);
}

/* Transpose chars before or at the point. */
static void vty_transpose_chars(struct vty *vty)
{
	char c1, c2;

	/* If length is short or point is near by the beginning of line then
	   return. */
	if (vty->length < 2 || vty->cp < 1)
		return;

	/* In case of point is located at the end of the line. */
	if (vty->cp == vty->length) {
		c1 = vty->buf[vty->cp - 1];
		c2 = vty->buf[vty->cp - 2];

		vty_backward_char(vty);
		vty_backward_char(vty);
		vty_self_insert_overwrite(vty, c1);
		vty_self_insert_overwrite(vty, c2);
	} else {
		c1 = vty->buf[vty->cp];
		c2 = vty->buf[vty->cp - 1];

		vty_backward_char(vty);
		vty_self_insert_overwrite(vty, c1);
		vty_self_insert_overwrite(vty, c2);
	}
}

/* Do completion at vty interface. */
static void vty_complete_command(struct vty *vty)
{
	int i;
	int ret;
	char **matched = NULL;
	vector vline;

	if (vty->node == AUTH_NODE || vty->node == AUTH_ENABLE_NODE)
		return;

	vline = cmd_make_strvec(vty->buf);
	if (vline == NULL)
		return;

	/* In case of 'help \t'. */
	if (isspace((unsigned char)vty->buf[vty->length - 1]))
		vector_set(vline, NULL);

	matched = cmd_complete_command(vline, vty, &ret);

	cmd_free_strvec(vline);

	vty_out(vty, "\n");
	switch (ret) {
	case CMD_ERR_AMBIGUOUS:
		vty_out(vty, "%% Ambiguous command.\n");
		vty_prompt(vty);
		vty_redraw_line(vty);
		break;
	case CMD_ERR_NO_MATCH:
		/* vty_out (vty, "%% There is no matched command.\n"); */
		vty_prompt(vty);
		vty_redraw_line(vty);
		break;
	case CMD_COMPLETE_FULL_MATCH:
		if (!matched[0]) {
			/* 2016-11-28 equinox -- need to debug, SEGV here */
			vty_out(vty, "%% CLI BUG: FULL_MATCH with NULL str\n");
			vty_prompt(vty);
			vty_redraw_line(vty);
			break;
		}
		vty_prompt(vty);
		vty_redraw_line(vty);
		vty_backward_pure_word(vty);
		vty_insert_word_overwrite(vty, matched[0]);
		vty_self_insert(vty, ' ');
		XFREE(MTYPE_COMPLETION, matched[0]);
		break;
	case CMD_COMPLETE_MATCH:
		vty_prompt(vty);
		vty_redraw_line(vty);
		vty_backward_pure_word(vty);
		vty_insert_word_overwrite(vty, matched[0]);
		XFREE(MTYPE_COMPLETION, matched[0]);
		break;
	case CMD_COMPLETE_LIST_MATCH:
		for (i = 0; matched[i] != NULL; i++) {
			if (i != 0 && ((i % 6) == 0))
				vty_out(vty, "\n");
			vty_out(vty, "%-10s ", matched[i]);
			XFREE(MTYPE_COMPLETION, matched[i]);
		}
		vty_out(vty, "\n");

		vty_prompt(vty);
		vty_redraw_line(vty);
		break;
	case CMD_ERR_NOTHING_TODO:
		vty_prompt(vty);
		vty_redraw_line(vty);
		break;
	default:
		break;
	}
	XFREE(MTYPE_TMP, matched);
}

static void vty_describe_fold(struct vty *vty, int cmd_width,
			      unsigned int desc_width, struct cmd_token *token)
{
	char *buf;
	const char *cmd, *p;
	int pos;

	cmd = token->text;

	if (desc_width <= 0) {
		vty_out(vty, "  %-*s  %s\n", cmd_width, cmd, token->desc);
		return;
	}

	buf = XCALLOC(MTYPE_TMP, strlen(token->desc) + 1);

	for (p = token->desc; strlen(p) > desc_width; p += pos + 1) {
		for (pos = desc_width; pos > 0; pos--)
			if (*(p + pos) == ' ')
				break;

		if (pos == 0)
			break;

		memcpy(buf, p, pos);
		buf[pos] = '\0';
		vty_out(vty, "  %-*s  %s\n", cmd_width, cmd, buf);

		cmd = "";
	}

	vty_out(vty, "  %-*s  %s\n", cmd_width, cmd, p);

	XFREE(MTYPE_TMP, buf);
}

/* Describe matched command function. */
static void vty_describe_command(struct vty *vty)
{
	int ret;
	vector vline;
	vector describe;
	unsigned int i, width, desc_width;
	struct cmd_token *token, *token_cr = NULL;

	vline = cmd_make_strvec(vty->buf);

	/* In case of '> ?'. */
	if (vline == NULL) {
		vline = vector_init(1);
		vector_set(vline, NULL);
	} else if (isspace((unsigned char)vty->buf[vty->length - 1]))
		vector_set(vline, NULL);

	describe = cmd_describe_command(vline, vty, &ret);

	vty_out(vty, "\n");

	/* Ambiguous error. */
	switch (ret) {
	case CMD_ERR_AMBIGUOUS:
		vty_out(vty, "%% Ambiguous command.\n");
		goto out;
		break;
	case CMD_ERR_NO_MATCH:
		vty_out(vty, "%% There is no matched command.\n");
		goto out;
		break;
	}

	/* Get width of command string. */
	width = 0;
	for (i = 0; i < vector_active(describe); i++)
		if ((token = vector_slot(describe, i)) != NULL) {
			unsigned int len;

			if (token->text[0] == '\0')
				continue;

			len = strlen(token->text);

			if (width < len)
				width = len;
		}

	/* Get width of description string. */
	desc_width = vty->width - (width + 6);

	/* Print out description. */
	for (i = 0; i < vector_active(describe); i++)
		if ((token = vector_slot(describe, i)) != NULL) {
			if (token->text[0] == '\0')
				continue;

			if (strcmp(token->text, CMD_CR_TEXT) == 0) {
				token_cr = token;
				continue;
			}

			if (!token->desc)
				vty_out(vty, "  %-s\n", token->text);
			else if (desc_width >= strlen(token->desc))
				vty_out(vty, "  %-*s  %s\n", width, token->text,
					token->desc);
			else
				vty_describe_fold(vty, width, desc_width,
						  token);

			if (IS_VARYING_TOKEN(token->type)) {
				const char *ref = vector_slot(
					vline, vector_active(vline) - 1);

				vector varcomps = vector_init(VECTOR_MIN_SIZE);
				cmd_variable_complete(token, ref, varcomps);

				if (vector_active(varcomps) > 0) {
					char *ac = cmd_variable_comp2str(
						varcomps, vty->width);
					vty_out(vty, "%s\n", ac);
					XFREE(MTYPE_TMP, ac);
				}

				vector_free(varcomps);
			}
		}

	if ((token = token_cr)) {
		if (!token->desc)
			vty_out(vty, "  %-s\n", token->text);
		else if (desc_width >= strlen(token->desc))
			vty_out(vty, "  %-*s  %s\n", width, token->text,
				token->desc);
		else
			vty_describe_fold(vty, width, desc_width, token);
	}

out:
	cmd_free_strvec(vline);
	if (describe)
		vector_free(describe);

	vty_prompt(vty);
	vty_redraw_line(vty);
}

static void vty_clear_buf(struct vty *vty)
{
	memset(vty->buf, 0, vty->max);
}

/* ^C stop current input and do not add command line to the history. */
static void vty_stop_input(struct vty *vty)
{
	vty->cp = vty->length = 0;
	vty_clear_buf(vty);
	vty_out(vty, "\n");

	if (vty->config) {
		vty_config_exit(vty);
		vty->node = ENABLE_NODE;
	}

	vty_prompt(vty);

	/* Set history pointer to the latest one. */
	vty->hp = vty->hindex;
}

/* Add current command line to the history buffer. */
static void vty_hist_add(struct vty *vty)
{
	int index;

	if (vty->length == 0)
		return;

	index = vty->hindex ? vty->hindex - 1 : VTY_MAXHIST - 1;

	/* Ignore the same string as previous one. */
	if (vty->hist[index])
		if (strcmp(vty->buf, vty->hist[index]) == 0) {
			vty->hp = vty->hindex;
			return;
		}

	/* Insert history entry. */
	XFREE(MTYPE_VTY_HIST, vty->hist[vty->hindex]);
	vty->hist[vty->hindex] = XSTRDUP(MTYPE_VTY_HIST, vty->buf);

	/* History index rotation. */
	vty->hindex++;
	if (vty->hindex == VTY_MAXHIST)
		vty->hindex = 0;

	vty->hp = vty->hindex;
}

/* #define TELNET_OPTION_DEBUG */

/* Get telnet window size. */
static int vty_telnet_option(struct vty *vty, unsigned char *buf, int nbytes)
{
#ifdef TELNET_OPTION_DEBUG
	int i;

	for (i = 0; i < nbytes; i++) {
		switch (buf[i]) {
		case IAC:
			vty_out(vty, "IAC ");
			break;
		case WILL:
			vty_out(vty, "WILL ");
			break;
		case WONT:
			vty_out(vty, "WONT ");
			break;
		case DO:
			vty_out(vty, "DO ");
			break;
		case DONT:
			vty_out(vty, "DONT ");
			break;
		case SB:
			vty_out(vty, "SB ");
			break;
		case SE:
			vty_out(vty, "SE ");
			break;
		case TELOPT_ECHO:
			vty_out(vty, "TELOPT_ECHO \n");
			break;
		case TELOPT_SGA:
			vty_out(vty, "TELOPT_SGA \n");
			break;
		case TELOPT_NAWS:
			vty_out(vty, "TELOPT_NAWS \n");
			break;
		default:
			vty_out(vty, "%x ", buf[i]);
			break;
		}
	}
	vty_out(vty, "\n");

#endif /* TELNET_OPTION_DEBUG */

	switch (buf[0]) {
	case SB:
		vty->sb_len = 0;
		vty->iac_sb_in_progress = 1;
		return 0;
	case SE: {
		if (!vty->iac_sb_in_progress)
			return 0;

		if ((vty->sb_len == 0) || (vty->sb_buf[0] == '\0')) {
			vty->iac_sb_in_progress = 0;
			return 0;
		}
		switch (vty->sb_buf[0]) {
		case TELOPT_NAWS:
			if (vty->sb_len != TELNET_NAWS_SB_LEN)
				flog_err(
					EC_LIB_SYSTEM_CALL,
					"RFC 1073 violation detected: telnet NAWS option should send %d characters, but we received %lu",
					TELNET_NAWS_SB_LEN,
					(unsigned long)vty->sb_len);
			else if (sizeof(vty->sb_buf) < TELNET_NAWS_SB_LEN)
				flog_err(
					EC_LIB_DEVELOPMENT,
					"Bug detected: sizeof(vty->sb_buf) %lu < %d, too small to handle the telnet NAWS option",
					(unsigned long)sizeof(vty->sb_buf),
					TELNET_NAWS_SB_LEN);
			else {
				vty->width = ((vty->sb_buf[1] << 8)
					      | vty->sb_buf[2]);
				vty->height = ((vty->sb_buf[3] << 8)
					       | vty->sb_buf[4]);
#ifdef TELNET_OPTION_DEBUG
				vty_out(vty,
					"TELNET NAWS window size negotiation completed: width %d, height %d\n",
					vty->width, vty->height);
#endif
			}
			break;
		}
		vty->iac_sb_in_progress = 0;
		return 0;
	}
	default:
		break;
	}
	return 1;
}

/* Execute current command line. */
static int vty_execute(struct vty *vty)
{
	int ret;

	ret = CMD_SUCCESS;

	switch (vty->node) {
	case AUTH_NODE:
	case AUTH_ENABLE_NODE:
		vty_auth(vty, vty->buf);
		break;
	default:
		ret = vty_command(vty, vty->buf);
		if (vty->type == VTY_TERM)
			vty_hist_add(vty);
		break;
	}

	/* Clear command line buffer. */
	vty->cp = vty->length = 0;
	vty_clear_buf(vty);

	if (vty->status != VTY_CLOSE)
		vty_prompt(vty);

	return ret;
}

#define CONTROL(X)  ((X) - '@')
#define VTY_NORMAL     0
#define VTY_PRE_ESCAPE 1
#define VTY_ESCAPE     2
#define VTY_CR         3

/* Escape character command map. */
static void vty_escape_map(unsigned char c, struct vty *vty)
{
	switch (c) {
	case ('A'):
		vty_previous_line(vty);
		break;
	case ('B'):
		vty_next_line(vty);
		break;
	case ('C'):
		vty_forward_char(vty);
		break;
	case ('D'):
		vty_backward_char(vty);
		break;
	default:
		break;
	}

	/* Go back to normal mode. */
	vty->escape = VTY_NORMAL;
}

/* Quit print out to the buffer. */
static void vty_buffer_reset(struct vty *vty)
{
	buffer_reset(vty->obuf);
	buffer_reset(vty->lbuf);
	vty_prompt(vty);
	vty_redraw_line(vty);
}

/* Read data via vty socket. */
static void vty_read(struct event *thread)
{
	int i;
	int nbytes;
	unsigned char buf[VTY_READ_BUFSIZ];

	struct vty *vty = EVENT_ARG(thread);

	/* Read raw data from socket */
	if ((nbytes = read(vty->fd, buf, VTY_READ_BUFSIZ)) <= 0) {
		if (nbytes < 0) {
			if (ERRNO_IO_RETRY(errno)) {
				vty_event(VTY_READ, vty);
				return;
			}
			flog_err(
				EC_LIB_SOCKET,
				"%s: read error on vty client fd %d, closing: %s",
				__func__, vty->fd, safe_strerror(errno));
			buffer_reset(vty->obuf);
			buffer_reset(vty->lbuf);
		}
		vty->status = VTY_CLOSE;
	}

	for (i = 0; i < nbytes; i++) {
		if (buf[i] == IAC) {
			if (!vty->iac) {
				vty->iac = 1;
				continue;
			} else {
				vty->iac = 0;
			}
		}

		if (vty->iac_sb_in_progress && !vty->iac) {
			if (vty->sb_len < sizeof(vty->sb_buf))
				vty->sb_buf[vty->sb_len] = buf[i];
			vty->sb_len++;
			continue;
		}

		if (vty->iac) {
			/* In case of telnet command */
			int ret = 0;
			ret = vty_telnet_option(vty, buf + i, nbytes - i);
			vty->iac = 0;
			i += ret;
			continue;
		}


		if (vty->status == VTY_MORE) {
			switch (buf[i]) {
			case CONTROL('C'):
			case 'q':
			case 'Q':
				vty_buffer_reset(vty);
				break;
			default:
				break;
			}
			continue;
		}

		/* Escape character. */
		if (vty->escape == VTY_ESCAPE) {
			vty_escape_map(buf[i], vty);
			continue;
		}

		/* Pre-escape status. */
		if (vty->escape == VTY_PRE_ESCAPE) {
			switch (buf[i]) {
			case '[':
				vty->escape = VTY_ESCAPE;
				break;
			case 'b':
				vty_backward_word(vty);
				vty->escape = VTY_NORMAL;
				break;
			case 'f':
				vty_forward_word(vty);
				vty->escape = VTY_NORMAL;
				break;
			case 'd':
				vty_forward_kill_word(vty);
				vty->escape = VTY_NORMAL;
				break;
			case CONTROL('H'):
			case 0x7f:
				vty_backward_kill_word(vty);
				vty->escape = VTY_NORMAL;
				break;
			default:
				vty->escape = VTY_NORMAL;
				break;
			}
			continue;
		}

		if (vty->escape == VTY_CR) {
			/* if we get CR+NL, the NL results in an extra empty
			 * prompt line being printed without this;  just drop
			 * the NL if it immediately follows CR.
			 */
			vty->escape = VTY_NORMAL;

			if (buf[i] == '\n')
				continue;
		}

		switch (buf[i]) {
		case CONTROL('A'):
			vty_beginning_of_line(vty);
			break;
		case CONTROL('B'):
			vty_backward_char(vty);
			break;
		case CONTROL('C'):
			vty_stop_input(vty);
			break;
		case CONTROL('D'):
			vty_delete_char(vty);
			break;
		case CONTROL('E'):
			vty_end_of_line(vty);
			break;
		case CONTROL('F'):
			vty_forward_char(vty);
			break;
		case CONTROL('H'):
		case 0x7f:
			vty_delete_backward_char(vty);
			break;
		case CONTROL('K'):
			vty_kill_line(vty);
			break;
		case CONTROL('N'):
			vty_next_line(vty);
			break;
		case CONTROL('P'):
			vty_previous_line(vty);
			break;
		case CONTROL('T'):
			vty_transpose_chars(vty);
			break;
		case CONTROL('U'):
			vty_kill_line_from_beginning(vty);
			break;
		case CONTROL('W'):
			vty_backward_kill_word(vty);
			break;
		case CONTROL('Z'):
			vty_end_config(vty);
			break;
		case '\r':
			vty->escape = VTY_CR;
			/* fallthru */
		case '\n':
			vty_out(vty, "\n");
			buffer_flush_available(vty->obuf, vty->wfd);
			vty_execute(vty);

			if (vty->pass_fd != -1) {
				close(vty->pass_fd);
				vty->pass_fd = -1;
			}
			break;
		case '\t':
			vty_complete_command(vty);
			break;
		case '?':
			if (vty->node == AUTH_NODE
			    || vty->node == AUTH_ENABLE_NODE)
				vty_self_insert(vty, buf[i]);
			else
				vty_describe_command(vty);
			break;
		case '\033':
			if (i + 1 < nbytes && buf[i + 1] == '[') {
				vty->escape = VTY_ESCAPE;
				i++;
			} else
				vty->escape = VTY_PRE_ESCAPE;
			break;
		default:
			if (buf[i] > 31 && buf[i] < 127)
				vty_self_insert(vty, buf[i]);
			break;
		}
	}

	/* Check status. */
	if (vty->status == VTY_CLOSE)
		vty_close(vty);
	else {
		vty_event(VTY_WRITE, vty);
		vty_event(VTY_READ, vty);
	}
}

/* Flush buffer to the vty. */
static void vty_flush(struct event *thread)
{
	int erase;
	buffer_status_t flushrc;
	struct vty *vty = EVENT_ARG(thread);

	/* Tempolary disable read thread. */
	if (vty->lines == 0)
		EVENT_OFF(vty->t_read);

	/* Function execution continue. */
	erase = ((vty->status == VTY_MORE || vty->status == VTY_MORELINE));

	/* N.B. if width is 0, that means we don't know the window size. */
	if ((vty->lines == 0) || (vty->width == 0) || (vty->height == 0))
		flushrc = buffer_flush_available(vty->obuf, vty->wfd);
	else if (vty->status == VTY_MORELINE)
		flushrc = buffer_flush_window(vty->obuf, vty->wfd, vty->width,
					      1, erase, 0);
	else
		flushrc = buffer_flush_window(
			vty->obuf, vty->wfd, vty->width,
			vty->lines >= 0 ? vty->lines : vty->height, erase, 0);
	switch (flushrc) {
	case BUFFER_ERROR:
		zlog_info("buffer_flush failed on vty client fd %d/%d, closing",
			  vty->fd, vty->wfd);
		buffer_reset(vty->lbuf);
		buffer_reset(vty->obuf);
		vty_close(vty);
		return;
	case BUFFER_EMPTY:
		if (vty->status == VTY_CLOSE)
			vty_close(vty);
		else {
			vty->status = VTY_NORMAL;
			if (vty->lines == 0)
				vty_event(VTY_READ, vty);
		}
		break;
	case BUFFER_PENDING:
		/* There is more data waiting to be written. */
		vty->status = VTY_MORE;
		if (vty->lines == 0)
			vty_event(VTY_WRITE, vty);
		break;
	}
}

/* Allocate new vty struct. */
struct vty *vty_new(void)
{
	struct vty *new = XCALLOC(MTYPE_VTY, sizeof(struct vty));

	new->fd = new->wfd = -1;
	new->of = stdout;
	new->lbuf = buffer_new(0);
	new->obuf = buffer_new(0); /* Use default buffer size. */
	new->buf = XCALLOC(MTYPE_VTY, VTY_BUFSIZ);
	new->max = VTY_BUFSIZ;
	new->pass_fd = -1;

	if (mgmt_fe_client) {
		if (!mgmt_client_id_next)
			mgmt_client_id_next++;
		new->mgmt_client_id = mgmt_client_id_next++;
		new->mgmt_session_id = 0;
		mgmt_fe_create_client_session(
			mgmt_fe_client, new->mgmt_client_id, (uintptr_t) new);
		/* we short-circuit create the session so it must be set now */
		assertf(new->mgmt_session_id != 0,
			"Failed to create client session for VTY");
	}

	return new;
}


/* allocate and initialise vty */
static struct vty *vty_new_init(int vty_sock)
{
	struct vty *vty;

	vty = vty_new();
	vty->fd = vty_sock;
	vty->wfd = vty_sock;
	vty->type = VTY_TERM;
	vty->node = AUTH_NODE;
	vty->fail = 0;
	vty->cp = 0;
	vty_clear_buf(vty);
	vty->length = 0;
	memset(vty->hist, 0, sizeof(vty->hist));
	vty->hp = 0;
	vty->hindex = 0;
	vty->xpath_index = 0;
	memset(vty->xpath, 0, sizeof(vty->xpath));
	vty->private_config = false;
	vty->candidate_config = vty_shared_candidate_config;
	vty->status = VTY_NORMAL;
	vty->lines = -1;
	vty->iac = 0;
	vty->iac_sb_in_progress = 0;
	vty->sb_len = 0;

	vtys_add_tail(vty_sessions, vty);

	return vty;
}

/* Create new vty structure. */
static struct vty *vty_create(int vty_sock, union sockunion *su)
{
	char buf[SU_ADDRSTRLEN];
	struct vty *vty;

	sockunion2str(su, buf, SU_ADDRSTRLEN);

	/* Allocate new vty structure and set up default values. */
	vty = vty_new_init(vty_sock);

	/* configurable parameters not part of basic init */
	vty->v_timeout = vty_timeout_val;
	strlcpy(vty->address, buf, sizeof(vty->address));
	if (no_password_check) {
		if (host.advanced)
			vty->node = ENABLE_NODE;
		else
			vty->node = VIEW_NODE;
	}
	if (host.lines >= 0)
		vty->lines = host.lines;

	if (!no_password_check) {
		/* Vty is not available if password isn't set. */
		if (host.password == NULL && host.password_encrypt == NULL) {
			vty_out(vty, "Vty password is not set.\n");
			vty->status = VTY_CLOSE;
			vty_close(vty);
			return NULL;
		}
	}

	/* Say hello to the world. */
	vty_hello(vty);
	if (!no_password_check)
		vty_out(vty, "\nUser Access Verification\n\n");

	/* Setting up terminal. */
	vty_will_echo(vty);
	vty_will_suppress_go_ahead(vty);

	vty_dont_linemode(vty);
	vty_do_window_size(vty);
	/* vty_dont_lflow_ahead (vty); */

	vty_prompt(vty);

	/* Add read/write thread. */
	vty_event(VTY_WRITE, vty);
	vty_event(VTY_READ, vty);

	return vty;
}

/* create vty for stdio */
static struct termios stdio_orig_termios;
static struct vty *stdio_vty = NULL;
static bool stdio_termios = false;
static void (*stdio_vty_atclose)(int isexit);

static void vty_stdio_reset(int isexit)
{
	if (stdio_vty) {
		if (stdio_termios)
			tcsetattr(0, TCSANOW, &stdio_orig_termios);
		stdio_termios = false;

		stdio_vty = NULL;

		if (stdio_vty_atclose)
			stdio_vty_atclose(isexit);
		stdio_vty_atclose = NULL;
	}
}

static void vty_stdio_atexit(void)
{
	vty_stdio_reset(1);
}

void vty_stdio_suspend(void)
{
	if (!stdio_vty)
		return;

	EVENT_OFF(stdio_vty->t_write);
	EVENT_OFF(stdio_vty->t_read);
	EVENT_OFF(stdio_vty->t_timeout);

	if (stdio_termios)
		tcsetattr(0, TCSANOW, &stdio_orig_termios);
	stdio_termios = false;
}

void vty_stdio_resume(void)
{
	if (!stdio_vty)
		return;

	if (!tcgetattr(0, &stdio_orig_termios)) {
		struct termios termios;

		termios = stdio_orig_termios;
		termios.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP | INLCR
				     | IGNCR | ICRNL | IXON);
		termios.c_lflag &= ~(ECHO | ECHONL | ICANON | IEXTEN);
		termios.c_cflag &= ~(CSIZE | PARENB);
		termios.c_cflag |= CS8;
		tcsetattr(0, TCSANOW, &termios);
		stdio_termios = true;
	}

	vty_prompt(stdio_vty);

	/* Add read/write thread. */
	vty_event(VTY_WRITE, stdio_vty);
	vty_event(VTY_READ, stdio_vty);
}

void vty_stdio_close(void)
{
	if (!stdio_vty)
		return;
	vty_close(stdio_vty);
}

struct vty *vty_stdio(void (*atclose)(int isexit))
{
	struct vty *vty;

	/* refuse creating two vtys on stdio */
	if (stdio_vty)
		return NULL;

	vty = stdio_vty = vty_new_init(0);
	stdio_vty_atclose = atclose;
	vty->wfd = 1;

	/* always have stdio vty in a known _unchangeable_ state, don't want
	 * config
	 * to have any effect here to make sure scripting this works as intended
	 */
	vty->node = ENABLE_NODE;
	vty->v_timeout = 0;
	strlcpy(vty->address, "console", sizeof(vty->address));

	vty_stdio_resume();
	return vty;
}

/* Accept connection from the network. */
static void vty_accept(struct event *thread)
{
	struct vty_serv *vtyserv = EVENT_ARG(thread);
	int vty_sock;
	union sockunion su;
	int ret;
	unsigned int on;
	int accept_sock = vtyserv->sock;
	struct prefix p;
	struct access_list *acl = NULL;

	/* We continue hearing vty socket. */
	vty_event_serv(VTY_SERV, vtyserv);

	memset(&su, 0, sizeof(union sockunion));

	/* We can handle IPv4 or IPv6 socket. */
	vty_sock = sockunion_accept(accept_sock, &su);
	if (vty_sock < 0) {
		flog_err(EC_LIB_SOCKET, "can't accept vty socket : %s",
			 safe_strerror(errno));
		return;
	}
	set_nonblocking(vty_sock);
	set_cloexec(vty_sock);

	if (!sockunion2hostprefix(&su, &p)) {
		close(vty_sock);
		zlog_info("Vty unable to convert prefix from sockunion %pSU",
			  &su);
		return;
	}

	/* VTY's accesslist apply. */
	if (p.family == AF_INET && vty_accesslist_name) {
		if ((acl = access_list_lookup(AFI_IP, vty_accesslist_name))
		    && (access_list_apply(acl, &p) == FILTER_DENY)) {
			zlog_info("Vty connection refused from %pSU", &su);
			close(vty_sock);
			return;
		}
	}

	/* VTY's ipv6 accesslist apply. */
	if (p.family == AF_INET6 && vty_ipv6_accesslist_name) {
		if ((acl = access_list_lookup(AFI_IP6,
					      vty_ipv6_accesslist_name))
		    && (access_list_apply(acl, &p) == FILTER_DENY)) {
			zlog_info("Vty connection refused from %pSU", &su);
			close(vty_sock);
			return;
		}
	}

	on = 1;
	ret = setsockopt(vty_sock, IPPROTO_TCP, TCP_NODELAY, (char *)&on,
			 sizeof(on));
	if (ret < 0)
		zlog_info("can't set sockopt to vty_sock : %s",
			  safe_strerror(errno));

	zlog_info("Vty connection from %pSU", &su);

	vty_create(vty_sock, &su);
}

static void vty_serv_sock_addrinfo(const char *hostname, unsigned short port)
{
	int ret;
	struct addrinfo req;
	struct addrinfo *ainfo;
	struct addrinfo *ainfo_save;
	int sock;
	char port_str[BUFSIZ];

	memset(&req, 0, sizeof(req));
	req.ai_flags = AI_PASSIVE;
	req.ai_family = AF_UNSPEC;
	req.ai_socktype = SOCK_STREAM;
	snprintf(port_str, sizeof(port_str), "%d", port);
	port_str[sizeof(port_str) - 1] = '\0';

	ret = getaddrinfo(hostname, port_str, &req, &ainfo);

	if (ret != 0) {
		flog_err_sys(EC_LIB_SYSTEM_CALL, "getaddrinfo failed: %s",
			     gai_strerror(ret));
		exit(1);
	}

	ainfo_save = ainfo;

	do {
		struct vty_serv *vtyserv;

		if (ainfo->ai_family != AF_INET && ainfo->ai_family != AF_INET6)
			continue;

		sock = socket(ainfo->ai_family, ainfo->ai_socktype,
			      ainfo->ai_protocol);
		if (sock < 0)
			continue;

		sockopt_v6only(ainfo->ai_family, sock);
		sockopt_reuseaddr(sock);
		sockopt_reuseport(sock);
		set_cloexec(sock);

		ret = bind(sock, ainfo->ai_addr, ainfo->ai_addrlen);
		if (ret < 0) {
			close(sock); /* Avoid sd leak. */
			continue;
		}

		ret = listen(sock, 3);
		if (ret < 0) {
			close(sock); /* Avoid sd leak. */
			continue;
		}

		vtyserv = XCALLOC(MTYPE_VTY_SERV, sizeof(*vtyserv));
		vtyserv->sock = sock;
		vtyservs_add_tail(vty_servs, vtyserv);

		vty_event_serv(VTY_SERV, vtyserv);
	} while ((ainfo = ainfo->ai_next) != NULL);

	freeaddrinfo(ainfo_save);
}

#ifdef VTYSH
/* For sockaddr_un. */
#include <sys/un.h>

/* VTY shell UNIX domain socket. */
static void vty_serv_un(const char *path)
{
	struct vty_serv *vtyserv;
	int ret;
	int sock, len;
	struct sockaddr_un serv;
	mode_t old_mask;
	struct zprivs_ids_t ids;

	/* First of all, unlink existing socket */
	unlink(path);

	/* Set umask */
	old_mask = umask(0007);

	/* Make UNIX domain socket. */
	sock = socket(AF_UNIX, SOCK_STREAM, 0);
	if (sock < 0) {
		flog_err_sys(EC_LIB_SOCKET,
			     "Cannot create unix stream socket: %s",
			     safe_strerror(errno));
		return;
	}

	/* Make server socket. */
	memset(&serv, 0, sizeof(serv));
	serv.sun_family = AF_UNIX;
	strlcpy(serv.sun_path, path, sizeof(serv.sun_path));
#ifdef HAVE_STRUCT_SOCKADDR_UN_SUN_LEN
	len = serv.sun_len = SUN_LEN(&serv);
#else
	len = sizeof(serv.sun_family) + strlen(serv.sun_path);
#endif /* HAVE_STRUCT_SOCKADDR_UN_SUN_LEN */

	set_cloexec(sock);

	ret = bind(sock, (struct sockaddr *)&serv, len);
	if (ret < 0) {
		flog_err_sys(EC_LIB_SOCKET, "Cannot bind path %s: %s", path,
			     safe_strerror(errno));
		close(sock); /* Avoid sd leak. */
		return;
	}

	ret = listen(sock, 5);
	if (ret < 0) {
		flog_err_sys(EC_LIB_SOCKET, "listen(fd %d) failed: %s", sock,
			     safe_strerror(errno));
		close(sock); /* Avoid sd leak. */
		return;
	}

	umask(old_mask);

	zprivs_get_ids(&ids);

	/* Hack: ids.gid_vty is actually a uint, but we stored -1 in it
	   earlier for the case when we don't need to chown the file
	   type casting it here to make a compare */
	if ((int)ids.gid_vty > 0) {
		/* set group of socket */
		if (chown(path, -1, ids.gid_vty)) {
			flog_err_sys(EC_LIB_SYSTEM_CALL,
				     "vty_serv_un: could chown socket, %s",
				     safe_strerror(errno));
		}
	}

	vtyserv = XCALLOC(MTYPE_VTY_SERV, sizeof(*vtyserv));
	vtyserv->sock = sock;
	vtyserv->vtysh = true;
	vtyservs_add_tail(vty_servs, vtyserv);

	vty_event_serv(VTYSH_SERV, vtyserv);
}

/* #define VTYSH_DEBUG 1 */

static void vtysh_accept(struct event *thread)
{
	struct vty_serv *vtyserv = EVENT_ARG(thread);
	int accept_sock = vtyserv->sock;
	int sock;
	int client_len;
	struct sockaddr_un client;
	struct vty *vty;

	vty_event_serv(VTYSH_SERV, vtyserv);

	memset(&client, 0, sizeof(client));
	client_len = sizeof(struct sockaddr_un);

	sock = accept(accept_sock, (struct sockaddr *)&client,
		      (socklen_t *)&client_len);

	if (sock < 0) {
		flog_err(EC_LIB_SOCKET, "can't accept vty socket : %s",
			 safe_strerror(errno));
		return;
	}

	if (set_nonblocking(sock) < 0) {
		flog_err(
			EC_LIB_SOCKET,
			"vtysh_accept: could not set vty socket %d to non-blocking, %s, closing",
			sock, safe_strerror(errno));
		close(sock);
		return;
	}
	set_cloexec(sock);

#ifdef VTYSH_DEBUG
	printf("VTY shell accept\n");
#endif /* VTYSH_DEBUG */

	vty = vty_new();
	vty->fd = sock;
	vty->wfd = sock;
	vty->type = VTY_SHELL_SERV;
	vty->node = VIEW_NODE;
	vtys_add_tail(vtysh_sessions, vty);

	vty_event(VTYSH_READ, vty);
}

static int vtysh_do_pass_fd(struct vty *vty)
{
	struct iovec iov[1] = {
		{
			.iov_base = vty->pass_fd_status,
			.iov_len = sizeof(vty->pass_fd_status),
		},
	};
	union {
		uint8_t buf[CMSG_SPACE(sizeof(int))];
		struct cmsghdr align;
	} u;
	struct msghdr mh = {
		.msg_iov = iov,
		.msg_iovlen = array_size(iov),
		.msg_control = u.buf,
		.msg_controllen = sizeof(u.buf),
	};
	struct cmsghdr *cmh = CMSG_FIRSTHDR(&mh);
	ssize_t ret;

	memset(&u.buf, 0, sizeof(u.buf));
	cmh->cmsg_level = SOL_SOCKET;
	cmh->cmsg_type = SCM_RIGHTS;
	cmh->cmsg_len = CMSG_LEN(sizeof(int));
	memcpy(CMSG_DATA(cmh), &vty->pass_fd, sizeof(int));

	ret = sendmsg(vty->wfd, &mh, 0);
	if (ret < 0 && ERRNO_IO_RETRY(errno))
		return BUFFER_PENDING;

	close(vty->pass_fd);
	vty->pass_fd = -1;
	vty->status = VTY_NORMAL;

	if (ret <= 0)
		return BUFFER_ERROR;

	/* resume accepting commands (suspended in vtysh_read) */
	vty_event(VTYSH_READ, vty);

	if ((size_t)ret < sizeof(vty->pass_fd_status)) {
		size_t remains = sizeof(vty->pass_fd_status) - ret;

		buffer_put(vty->obuf, vty->pass_fd_status + ret, remains);
		return BUFFER_PENDING;
	}
	return BUFFER_EMPTY;
}

static int vtysh_flush(struct vty *vty)
{
	int ret;

	ret = buffer_flush_available(vty->obuf, vty->wfd);
	if (ret == BUFFER_EMPTY && vty->status == VTY_PASSFD)
		ret = vtysh_do_pass_fd(vty);

	switch (ret) {
	case BUFFER_PENDING:
		vty_event(VTYSH_WRITE, vty);
		break;
	case BUFFER_ERROR:
		flog_err(EC_LIB_SOCKET, "%s: write error to fd %d, closing",
			 __func__, vty->fd);
		buffer_reset(vty->lbuf);
		buffer_reset(vty->obuf);
		vty_close(vty);
		return -1;
	case BUFFER_EMPTY:
		break;
	}
	return 0;
}

void vty_pass_fd(struct vty *vty, int fd)
{
	if (vty->pass_fd != -1)
		close(vty->pass_fd);

	vty->pass_fd = fd;
}

bool mgmt_vty_read_configs(void)
{
	char path[PATH_MAX];
	struct vty *vty;
	FILE *confp;
	uint line_num = 0;
	uint count = 0;
	uint index;

	vty = vty_new();
	vty->wfd = STDERR_FILENO;
	vty->type = VTY_FILE;
	vty->node = CONFIG_NODE;
	vty->config = true;
	vty->pending_allowed = true;

	vty->candidate_config = vty_shared_candidate_config;

	vty_mgmt_lock_candidate_inline(vty);
	vty_mgmt_lock_running_inline(vty);

	for (index = 0; index < array_size(mgmt_daemons); index++) {
		snprintf(path, sizeof(path), "%s/%s.conf", frr_sysconfdir,
			 mgmt_daemons[index]);

		confp = vty_open_config(path, config_default);
		if (!confp)
			continue;

		zlog_info("mgmtd: reading config file: %s", path);

		/* Execute configuration file */
		line_num = 0;
		(void)config_from_file(vty, confp, &line_num);
		count++;

		fclose(confp);
	}

	snprintf(path, sizeof(path), "%s/mgmtd.conf", frr_sysconfdir);
	confp = vty_open_config(path, config_default);
	if (!confp) {
		char *orig;

		snprintf(path, sizeof(path), "%s/zebra.conf", frr_sysconfdir);
		orig = XSTRDUP(MTYPE_TMP, host_config_get());

		zlog_info("mgmtd: trying backup config file: %s", path);
		confp = vty_open_config(path, config_default);

		host_config_set(path);
		XFREE(MTYPE_TMP, orig);
	}

	if (confp) {
		zlog_info("mgmtd: reading config file: %s", path);

		line_num = 0;
		(void)config_from_file(vty, confp, &line_num);
		count++;

		fclose(confp);
	}

	/* Conditionally unlock as the config file may have "exit"d early which
	 * would then have unlocked things.
	 */
	if (vty->mgmt_locked_running_ds)
		vty_mgmt_unlock_running_inline(vty);
	if (vty->mgmt_locked_candidate_ds)
		vty_mgmt_unlock_candidate_inline(vty);

	vty->pending_allowed = false;

	if (!count)
		vty_close(vty);
	else
		vty_read_file_finish(vty, NULL);

	zlog_info("mgmtd: finished reading config files");

	return true;
}

static void vtysh_read(struct event *thread)
{
	int ret;
	int sock;
	int nbytes;
	struct vty *vty;
	unsigned char buf[VTY_READ_BUFSIZ];
	unsigned char *p;
	uint8_t header[4] = {0, 0, 0, 0};

	sock = EVENT_FD(thread);
	vty = EVENT_ARG(thread);

	/*
	 * This code looks like it can read multiple commands from the `buf`
	 * value returned by read(); however, it cannot in some cases.
	 *
	 * There are multiple paths out of the "copying to vty->buf" loop, which
	 * lose any content not yet copied from the stack `buf`, `passfd`,
	 * `CMD_SUSPEND` and finally if a front-end for mgmtd (generally this
	 * would be mgmtd itself). So these code paths are counting on vtysh not
	 * sending us more than 1 command line before waiting on the reply to
	 * that command.
	 */
	assert(vty->type == VTY_SHELL_SERV);

	if ((nbytes = read(sock, buf, VTY_READ_BUFSIZ)) <= 0) {
		if (nbytes < 0) {
			if (ERRNO_IO_RETRY(errno)) {
				vty_event(VTYSH_READ, vty);
				return;
			}
			flog_err(
				EC_LIB_SOCKET,
				"%s: read failed on vtysh client fd %d, closing: %s",
				__func__, sock, safe_strerror(errno));
		}
		buffer_reset(vty->lbuf);
		buffer_reset(vty->obuf);
		vty_close(vty);
#ifdef VTYSH_DEBUG
		printf("close vtysh\n");
#endif /* VTYSH_DEBUG */
		return;
	}

#ifdef VTYSH_DEBUG
	printf("line: %.*s\n", nbytes, buf);
#endif /* VTYSH_DEBUG */

	if (vty->length + nbytes >= VTY_BUFSIZ) {
		/* Clear command line buffer. */
		vty->cp = vty->length = 0;
		vty_clear_buf(vty);
		vty_out(vty, "%% Command is too long.\n");
	} else {
		for (p = buf; p < buf + nbytes; p++) {
			vty->buf[vty->length++] = *p;
			if (*p == '\0') {
				/* Pass this line to parser. */
				ret = vty_execute(vty);
/* Note that vty_execute clears the command buffer and resets
   vty->length to 0. */

/* Return result. */
#ifdef VTYSH_DEBUG
				printf("result: %d\n", ret);
				printf("vtysh node: %d\n", vty->node);
#endif /* VTYSH_DEBUG */
				if (vty->pass_fd >= 0) {
					memset(vty->pass_fd_status, 0, 4);
					vty->pass_fd_status[3] = ret;
					vty->status = VTY_PASSFD;

					if (!vty->t_write)
						vty_event(VTYSH_WRITE, vty);

					/* this introduces a "sequence point"
					 * command output is written normally,
					 * read processing is suspended until
					 * buffer is empty
					 * then retcode + FD is written
					 * then normal processing resumes
					 *
					 * => skip vty_event(VTYSH_READ, vty)!
					 */
					return;
				} else {
					assertf(vty->status != VTY_PASSFD,
						"%p address=%s passfd=%d", vty,
						vty->address, vty->pass_fd);

					/* normalize other invalid values */
					vty->pass_fd = -1;
				}

				/* hack for asynchronous "write integrated"
				 * - other commands in "buf" will be ditched
				 * - input during pending config-write is
				 * "unsupported" */
				if (ret == CMD_SUSPEND)
					break;

				/* with new infra we need to stop response till
				 * we get response through callback.
				 */
				if (vty->mgmt_req_pending_cmd) {
					MGMTD_FE_CLIENT_DBG(
						"postpone CLI response pending mgmtd %s on vty session-id %" PRIu64,
						vty->mgmt_req_pending_cmd,
						vty->mgmt_session_id);
					return;
				}

				/* warning: watchfrr hardcodes this result write
				 */
				header[3] = ret;
				buffer_put(vty->obuf, header, 4);

				if (!vty->t_write && (vtysh_flush(vty) < 0))
					/* Try to flush results; exit if a write
					 * error occurs. */
					return;
			}
		}
	}

	if (vty->status == VTY_CLOSE)
		vty_close(vty);
	else
		vty_event(VTYSH_READ, vty);
}

static void vtysh_write(struct event *thread)
{
	struct vty *vty = EVENT_ARG(thread);

	vtysh_flush(vty);
}

#endif /* VTYSH */

/* Determine address family to bind. */
void vty_serv_start(const char *addr, unsigned short port, const char *path)
{
	/* If port is set to 0, do not listen on TCP/IP at all! */
	if (port)
		vty_serv_sock_addrinfo(addr, port);

#ifdef VTYSH
	vty_serv_un(path);
#endif /* VTYSH */
}

void vty_serv_stop(void)
{
	struct vty_serv *vtyserv;

	while ((vtyserv = vtyservs_pop(vty_servs))) {
		EVENT_OFF(vtyserv->t_accept);
		close(vtyserv->sock);
		XFREE(MTYPE_VTY_SERV, vtyserv);
	}

	vtyservs_fini(vty_servs);
	vtyservs_init(vty_servs);
}

static void vty_error_delete(void *arg)
{
	struct vty_error *ve = arg;

	XFREE(MTYPE_TMP, ve);
}

/* Close vty interface.  Warning: call this only from functions that
   will be careful not to access the vty afterwards (since it has
   now been freed).  This is safest from top-level functions (called
   directly by the thread dispatcher). */
void vty_close(struct vty *vty)
{
	int i;
	bool was_stdio = false;

	vty->status = VTY_CLOSE;

	/*
	 * If we reach here with pending config to commit we will be losing it
	 * so warn the user.
	 */
	if (vty->mgmt_num_pending_setcfg)
		MGMTD_FE_CLIENT_ERR(
			"vty closed, uncommitted config will be lost.");

	/* Drop out of configure / transaction if needed. */
	vty_config_exit(vty);

	if (mgmt_fe_client && vty->mgmt_session_id) {
		MGMTD_FE_CLIENT_DBG("closing vty session");
		mgmt_fe_destroy_client_session(mgmt_fe_client,
					       vty->mgmt_client_id);
		vty->mgmt_session_id = 0;
	}

	/* Cancel threads.*/
	EVENT_OFF(vty->t_read);
	EVENT_OFF(vty->t_write);
	EVENT_OFF(vty->t_timeout);

	if (vty->pass_fd != -1) {
		close(vty->pass_fd);
		vty->pass_fd = -1;
	}
	zlog_live_close(&vty->live_log);

	/* Flush buffer. */
	buffer_flush_all(vty->obuf, vty->wfd);

	/* Free input buffer. */
	buffer_free(vty->obuf);
	buffer_free(vty->lbuf);

	/* Free command history. */
	for (i = 0; i < VTY_MAXHIST; i++) {
		XFREE(MTYPE_VTY_HIST, vty->hist[i]);
	}

	/* Unset vector. */
	if (vty->fd != -1) {
		if (vty->type == VTY_SHELL_SERV)
			vtys_del(vtysh_sessions, vty);
		else if (vty->type == VTY_TERM)
			vtys_del(vty_sessions, vty);
	}

	if (vty->wfd > 0 && vty->type == VTY_FILE)
		fsync(vty->wfd);

	/* Close socket.
	 * note check is for fd > STDERR_FILENO, not fd != -1.
	 * We never close stdin/stdout/stderr here, because we may be
	 * running in foreground mode with logging to stdout.  Also,
	 * additionally, we'd need to replace these fds with /dev/null. */
	if (vty->wfd > STDERR_FILENO && vty->wfd != vty->fd)
		close(vty->wfd);
	if (vty->fd > STDERR_FILENO)
		close(vty->fd);
	if (vty->fd == STDIN_FILENO)
		was_stdio = true;

	XFREE(MTYPE_TMP, vty->pending_cmds_buf);
	XFREE(MTYPE_VTY, vty->buf);

	if (vty->error) {
		vty->error->del = vty_error_delete;
		list_delete(&vty->error);
	}

	/* OK free vty. */
	XFREE(MTYPE_VTY, vty);

	if (was_stdio)
		vty_stdio_reset(0);
}

/* When time out occur output message then close connection. */
static void vty_timeout(struct event *thread)
{
	struct vty *vty;

	vty = EVENT_ARG(thread);
	vty->v_timeout = 0;

	/* Clear buffer*/
	buffer_reset(vty->lbuf);
	buffer_reset(vty->obuf);
	vty_out(vty, "\nVty connection is timed out.\n");

	/* Close connection. */
	vty->status = VTY_CLOSE;
	vty_close(vty);
}

/* Read up configuration file from file_name. */
void vty_read_file(struct nb_config *config, FILE *confp)
{
	struct vty *vty;
	unsigned int line_num = 0;

	vty = vty_new();
	/* vty_close won't close stderr;  if some config command prints
	 * something it'll end up there.  (not ideal; it'd be better if output
	 * from a file-load went to logging instead.  Also note that if this
	 * function is called after daemonizing, stderr will be /dev/null.)
	 *
	 * vty->fd will be -1 from vty_new()
	 */
	vty->wfd = STDERR_FILENO;
	vty->type = VTY_FILE;
	vty->node = CONFIG_NODE;
	vty->config = true;
	if (config)
		vty->candidate_config = config;
	else {
		vty->private_config = true;
		vty->candidate_config = nb_config_new(NULL);
	}

	/* Execute configuration file */
	(void)config_from_file(vty, confp, &line_num);

	vty_read_file_finish(vty, config);
}

void vty_read_file_finish(struct vty *vty, struct nb_config *config)
{
	struct vty_error *ve;
	struct listnode *node;

	/* Flush any previous errors before printing messages below */
	buffer_flush_all(vty->obuf, vty->wfd);

	for (ALL_LIST_ELEMENTS_RO(vty->error, node, ve)) {
		const char *message = NULL;
		char *nl;

		switch (ve->cmd_ret) {
		case CMD_SUCCESS:
			message = "Command succeeded";
			break;
		case CMD_ERR_NOTHING_TODO:
			message = "Nothing to do";
			break;
		case CMD_ERR_AMBIGUOUS:
			message = "Ambiguous command";
			break;
		case CMD_ERR_NO_MATCH:
			message = "No such command";
			break;
		case CMD_WARNING:
			message = "Command returned Warning";
			break;
		case CMD_WARNING_CONFIG_FAILED:
			message = "Command returned Warning Config Failed";
			break;
		case CMD_ERR_INCOMPLETE:
			message = "Command returned Incomplete";
			break;
		case CMD_ERR_EXEED_ARGC_MAX:
			message =
				"Command exceeded maximum number of Arguments";
			break;
		default:
			message = "Command returned unhandled error message";
			break;
		}

		nl = strchr(ve->error_buf, '\n');
		if (nl)
			*nl = '\0';
		flog_err(EC_LIB_VTY, "%s on config line %u: %s", message,
			 ve->line_num, ve->error_buf);
	}

	/*
	 * Automatically commit the candidate configuration after
	 * reading the configuration file.
	 */
	if (config == NULL) {
		struct nb_context context = {};
		char errmsg[BUFSIZ] = {0};
		int ret;

		context.client = NB_CLIENT_CLI;
		context.user = vty;
		ret = nb_candidate_commit(context, vty->candidate_config, true,
					  "Read configuration file", NULL,
					  errmsg, sizeof(errmsg));
		if (ret != NB_OK && ret != NB_ERR_NO_CHANGES)
			zlog_err(
				"%s: failed to read configuration file: %s (%s)",
				__func__, nb_err_name(ret), errmsg);
	}

	vty_close(vty);
}

static FILE *vty_use_backup_config(const char *fullpath)
{
	char *fullpath_sav, *fullpath_tmp;
	FILE *ret = NULL;
	int tmp, sav;
	int c;
	char buffer[512];

	size_t fullpath_sav_sz = strlen(fullpath) + strlen(CONF_BACKUP_EXT) + 1;
	fullpath_sav = malloc(fullpath_sav_sz);
	strlcpy(fullpath_sav, fullpath, fullpath_sav_sz);
	strlcat(fullpath_sav, CONF_BACKUP_EXT, fullpath_sav_sz);

	sav = open(fullpath_sav, O_RDONLY);
	if (sav < 0) {
		free(fullpath_sav);
		return NULL;
	}

	fullpath_tmp = malloc(strlen(fullpath) + 8);
	snprintf(fullpath_tmp, strlen(fullpath) + 8, "%s.XXXXXX", fullpath);

	/* Open file to configuration write. */
	tmp = mkstemp(fullpath_tmp);
	if (tmp < 0)
		goto out_close_sav;

	if (fchmod(tmp, CONFIGFILE_MASK) != 0)
		goto out_close;

	while ((c = read(sav, buffer, 512)) > 0) {
		if (write(tmp, buffer, c) <= 0)
			goto out_close;
	}
	close(sav);
	close(tmp);

	if (rename(fullpath_tmp, fullpath) == 0)
		ret = fopen(fullpath, "r");
	else
		unlink(fullpath_tmp);

	if (0) {
	out_close:
		close(tmp);
		unlink(fullpath_tmp);
	out_close_sav:
		close(sav);
	}

	free(fullpath_sav);
	free(fullpath_tmp);
	return ret;
}

FILE *vty_open_config(const char *config_file, char *config_default_dir)
{
	char cwd[MAXPATHLEN];
	FILE *confp = NULL;
	const char *fullpath;
	char *tmp = NULL;

	/* If -f flag specified. */
	if (config_file != NULL) {
		if (!IS_DIRECTORY_SEP(config_file[0])) {
			if (getcwd(cwd, MAXPATHLEN) == NULL) {
				flog_err_sys(
					EC_LIB_SYSTEM_CALL,
					"%s: failure to determine Current Working Directory %d!",
					__func__, errno);
				goto tmp_free_and_out;
			}
			size_t tmp_len = strlen(cwd) + strlen(config_file) + 2;
			tmp = XMALLOC(MTYPE_TMP, tmp_len);
			snprintf(tmp, tmp_len, "%s/%s", cwd, config_file);
			fullpath = tmp;
		} else
			fullpath = config_file;

		confp = fopen(fullpath, "r");

		if (confp == NULL) {
			flog_warn(
				EC_LIB_BACKUP_CONFIG,
				"%s: failed to open configuration file %s: %s, checking backup",
				__func__, fullpath, safe_strerror(errno));

			confp = vty_use_backup_config(fullpath);
			if (confp)
				flog_warn(EC_LIB_BACKUP_CONFIG,
					  "using backup configuration file!");
			else {
				flog_err(
					EC_LIB_VTY,
					"%s: can't open configuration file [%s]",
					__func__, config_file);
				goto tmp_free_and_out;
			}
		}
	} else {

		host_config_set(config_default_dir);

#ifdef VTYSH
		int ret;
		struct stat conf_stat;

		/* !!!!PLEASE LEAVE!!!!
		 * This is NEEDED for use with vtysh -b, or else you can get
		 * a real configuration food fight with a lot garbage in the
		 * merged configuration file it creates coming from the per
		 * daemon configuration files.  This also allows the daemons
		 * to start if there default configuration file is not
		 * present or ignore them, as needed when using vtysh -b to
		 * configure the daemons at boot - MAG
		 */

		/* Stat for vtysh Zebra.conf, if found startup and wait for
		 * boot configuration
		 */

		if (strstr(config_default_dir, "vtysh") == NULL) {
			ret = stat(integrate_default, &conf_stat);
			if (ret >= 0)
				goto tmp_free_and_out;
		}
#endif /* VTYSH */
		confp = fopen(config_default_dir, "r");
		if (confp == NULL) {
			flog_err(
				EC_LIB_SYSTEM_CALL,
				"%s: failed to open configuration file %s: %s, checking backup",
				__func__, config_default_dir,
				safe_strerror(errno));

			confp = vty_use_backup_config(config_default_dir);
			if (confp) {
				flog_warn(EC_LIB_BACKUP_CONFIG,
					  "using backup configuration file!");
				fullpath = config_default_dir;
			} else {
				flog_err(EC_LIB_VTY,
					 "can't open configuration file [%s]",
					 config_default_dir);
				goto tmp_free_and_out;
			}
		} else
			fullpath = config_default_dir;
	}

	host_config_set(fullpath);

tmp_free_and_out:
	XFREE(MTYPE_TMP, tmp);

	return confp;
}


bool vty_read_config(struct nb_config *config, const char *config_file,
		     char *config_default_dir)
{
	FILE *confp;

	confp = vty_open_config(config_file, config_default_dir);
	if (!confp)
		return false;

	vty_read_file(config, confp);

	fclose(confp);

	return true;
}

int vty_config_enter(struct vty *vty, bool private_config, bool exclusive,
		     bool file_lock)
{
	if (exclusive && !vty_mgmt_fe_enabled() &&
	    nb_running_lock(NB_CLIENT_CLI, vty)) {
		vty_out(vty, "%% Configuration is locked by other client\n");
		return CMD_WARNING;
	}

	/*
	 * We only need to do a lock when reading a config file as we will be
	 * sending a batch of setcfg changes followed by a single commit
	 * message. For user interactive mode we are doing implicit commits
	 * those will obtain the lock (or not) when they try and commit.
	 */
	if (file_lock && vty_mgmt_fe_enabled() && !private_config) {
		if (vty_mgmt_lock_candidate_inline(vty)) {
			vty_out(vty,
				"%% Can't enter config; candidate datastore locked by another session\n");
			return CMD_WARNING_CONFIG_FAILED;
		}
		if (vty_mgmt_lock_running_inline(vty)) {
			vty_out(vty,
				"%% Can't enter config; running datastore locked by another session\n");
			vty_mgmt_unlock_candidate_inline(vty);
			return CMD_WARNING_CONFIG_FAILED;
		}
		assert(vty->mgmt_locked_candidate_ds);
		assert(vty->mgmt_locked_running_ds);

		/*
		 * As datastores are locked explicitly, we don't need implicit
		 * commits and should allow pending changes.
		 */
		vty->pending_allowed = true;
	}

	vty->node = CONFIG_NODE;
	vty->config = true;
	vty->private_config = private_config;
	vty->xpath_index = 0;

	if (private_config) {
		vty->candidate_config = nb_config_dup(running_config);
		vty->candidate_config_base = nb_config_dup(running_config);
		vty_out(vty,
			"Warning: uncommitted changes will be discarded on exit.\n\n");
		return CMD_SUCCESS;
	}

	/*
	 * NOTE: On the MGMTD daemon we point the VTY candidate DS to
	 * the global MGMTD candidate DS. Else we point to the VTY
	 * Shared Candidate Config.
	 */
	vty->candidate_config = vty_mgmt_candidate_config
					? vty_mgmt_candidate_config
					: vty_shared_candidate_config;
	if (frr_get_cli_mode() == FRR_CLI_TRANSACTIONAL)
		vty->candidate_config_base = nb_config_dup(running_config);

	return CMD_SUCCESS;
}


void vty_config_exit(struct vty *vty)
{
	enum node_type node = vty->node;
	struct cmd_node *cnode;

	/* unlock and jump up to ENABLE_NODE if -and only if- we're
	 * somewhere below CONFIG_NODE */
	while (node && node != CONFIG_NODE) {
		cnode = vector_lookup(cmdvec, node);
		node = cnode->parent_node;
	}
	if (node != CONFIG_NODE)
		/* called outside config, e.g. vty_close() in ENABLE_NODE */
		return;

	while (vty->node != ENABLE_NODE)
		/* will call vty_config_node_exit() below */
		cmd_exit(vty);
}

int vty_config_node_exit(struct vty *vty)
{
	vty->xpath_index = 0;

	/* TODO: could we check for un-commited changes here? */

	vty->pending_allowed = false;

	if (vty->mgmt_locked_running_ds)
		vty_mgmt_unlock_running_inline(vty);

	if (vty->mgmt_locked_candidate_ds)
		vty_mgmt_unlock_candidate_inline(vty);

	/* Perform any pending commits. */
	(void)nb_cli_pending_commit_check(vty);

	/* Check if there's a pending confirmed commit. */
	if (vty->t_confirmed_commit_timeout) {
		vty_out(vty,
			"exiting with a pending confirmed commit. Rolling back to previous configuration.\n\n");
		nb_cli_confirmed_commit_rollback(vty);
		nb_cli_confirmed_commit_clean(vty);
	}

	(void)nb_running_unlock(NB_CLIENT_CLI, vty);

	if (vty->candidate_config) {
		if (vty->private_config)
			nb_config_free(vty->candidate_config);
		vty->candidate_config = NULL;
	}
	if (vty->candidate_config_base) {
		nb_config_free(vty->candidate_config_base);
		vty->candidate_config_base = NULL;
	}

	vty->config = false;

	/*
	 * If this is a config file and we are dropping out of config end
	 * parsing.
	 */
	if (vty->type == VTY_FILE && vty->status != VTY_CLOSE) {
		vty_out(vty, "exit from config node while reading config file");
		vty->status = VTY_CLOSE;
	}

	return 1;
}

/* Master of the threads. */
static struct event_loop *vty_master;

static void vty_event_serv(enum vty_event event, struct vty_serv *vty_serv)
{
	switch (event) {
	case VTY_SERV:
		event_add_read(vty_master, vty_accept, vty_serv, vty_serv->sock,
			       &vty_serv->t_accept);
		break;
#ifdef VTYSH
	case VTYSH_SERV:
		event_add_read(vty_master, vtysh_accept, vty_serv,
			       vty_serv->sock, &vty_serv->t_accept);
		break;
#endif /* VTYSH */
	case VTY_READ:
	case VTY_WRITE:
	case VTY_TIMEOUT_RESET:
	case VTYSH_READ:
	case VTYSH_WRITE:
		assert(!"vty_event_serv() called incorrectly");
	}
}

static void vty_event(enum vty_event event, struct vty *vty)
{
	switch (event) {
#ifdef VTYSH
	case VTYSH_READ:
		event_add_read(vty_master, vtysh_read, vty, vty->fd,
			       &vty->t_read);
		break;
	case VTYSH_WRITE:
		event_add_write(vty_master, vtysh_write, vty, vty->wfd,
				&vty->t_write);
		break;
#endif /* VTYSH */
	case VTY_READ:
		event_add_read(vty_master, vty_read, vty, vty->fd,
			       &vty->t_read);

		/* Time out treatment. */
		if (vty->v_timeout) {
			EVENT_OFF(vty->t_timeout);
			event_add_timer(vty_master, vty_timeout, vty,
					vty->v_timeout, &vty->t_timeout);
		}
		break;
	case VTY_WRITE:
		event_add_write(vty_master, vty_flush, vty, vty->wfd,
				&vty->t_write);
		break;
	case VTY_TIMEOUT_RESET:
		EVENT_OFF(vty->t_timeout);
		if (vty->v_timeout)
			event_add_timer(vty_master, vty_timeout, vty,
					vty->v_timeout, &vty->t_timeout);
		break;
	case VTY_SERV:
	case VTYSH_SERV:
		assert(!"vty_event() called incorrectly");
	}
}

DEFUN_NOSH (config_who,
       config_who_cmd,
       "who",
       "Display who is on vty\n")
{
	struct vty *v;

	frr_each (vtys, vty_sessions, v)
		vty_out(vty, "%svty[%d] connected from %s%s.\n",
			v->config ? "*" : " ", v->fd, v->address,
			zlog_live_is_null(&v->live_log) ? "" : ", live log");
	return CMD_SUCCESS;
}

/* Move to vty configuration mode. */
DEFUN_NOSH (line_vty,
       line_vty_cmd,
       "line vty",
       "Configure a terminal line\n"
       "Virtual terminal\n")
{
	vty->node = VTY_NODE;
	return CMD_SUCCESS;
}

/* Set time out value. */
static int exec_timeout(struct vty *vty, const char *min_str,
			const char *sec_str)
{
	unsigned long timeout = 0;

	/* min_str and sec_str are already checked by parser.  So it must be
	   all digit string. */
	if (min_str) {
		timeout = strtol(min_str, NULL, 10);
		timeout *= 60;
	}
	if (sec_str)
		timeout += strtol(sec_str, NULL, 10);

	vty_timeout_val = timeout;
	vty->v_timeout = timeout;
	vty_event(VTY_TIMEOUT_RESET, vty);


	return CMD_SUCCESS;
}

DEFUN (exec_timeout_min,
       exec_timeout_min_cmd,
       "exec-timeout (0-35791)",
       "Set timeout value\n"
       "Timeout value in minutes\n")
{
	int idx_number = 1;
	return exec_timeout(vty, argv[idx_number]->arg, NULL);
}

DEFUN (exec_timeout_sec,
       exec_timeout_sec_cmd,
       "exec-timeout (0-35791) (0-2147483)",
       "Set the EXEC timeout\n"
       "Timeout in minutes\n"
       "Timeout in seconds\n")
{
	int idx_number = 1;
	int idx_number_2 = 2;
	return exec_timeout(vty, argv[idx_number]->arg,
			    argv[idx_number_2]->arg);
}

DEFUN (no_exec_timeout,
       no_exec_timeout_cmd,
       "no exec-timeout",
       NO_STR
       "Set the EXEC timeout\n")
{
	return exec_timeout(vty, NULL, NULL);
}

/* Set vty access class. */
DEFUN (vty_access_class,
       vty_access_class_cmd,
       "access-class WORD",
       "Filter connections based on an IP access list\n"
       "IP access list\n")
{
	int idx_word = 1;
	if (vty_accesslist_name)
		XFREE(MTYPE_VTY, vty_accesslist_name);

	vty_accesslist_name = XSTRDUP(MTYPE_VTY, argv[idx_word]->arg);

	return CMD_SUCCESS;
}

/* Clear vty access class. */
DEFUN (no_vty_access_class,
       no_vty_access_class_cmd,
       "no access-class [WORD]",
       NO_STR
       "Filter connections based on an IP access list\n"
       "IP access list\n")
{
	int idx_word = 2;
	const char *accesslist = (argc == 3) ? argv[idx_word]->arg : NULL;
	if (!vty_accesslist_name
	    || (argc == 3 && strcmp(vty_accesslist_name, accesslist))) {
		vty_out(vty, "Access-class is not currently applied to vty\n");
		return CMD_WARNING_CONFIG_FAILED;
	}

	XFREE(MTYPE_VTY, vty_accesslist_name);

	vty_accesslist_name = NULL;

	return CMD_SUCCESS;
}

/* Set vty access class. */
DEFUN (vty_ipv6_access_class,
       vty_ipv6_access_class_cmd,
       "ipv6 access-class WORD",
       IPV6_STR
       "Filter connections based on an IP access list\n"
       "IPv6 access list\n")
{
	int idx_word = 2;
	if (vty_ipv6_accesslist_name)
		XFREE(MTYPE_VTY, vty_ipv6_accesslist_name);

	vty_ipv6_accesslist_name = XSTRDUP(MTYPE_VTY, argv[idx_word]->arg);

	return CMD_SUCCESS;
}

/* Clear vty access class. */
DEFUN (no_vty_ipv6_access_class,
       no_vty_ipv6_access_class_cmd,
       "no ipv6 access-class [WORD]",
       NO_STR
       IPV6_STR
       "Filter connections based on an IP access list\n"
       "IPv6 access list\n")
{
	int idx_word = 3;
	const char *accesslist = (argc == 4) ? argv[idx_word]->arg : NULL;

	if (!vty_ipv6_accesslist_name
	    || (argc == 4 && strcmp(vty_ipv6_accesslist_name, accesslist))) {
		vty_out(vty,
			"IPv6 access-class is not currently applied to vty\n");
		return CMD_WARNING_CONFIG_FAILED;
	}

	XFREE(MTYPE_VTY, vty_ipv6_accesslist_name);

	vty_ipv6_accesslist_name = NULL;

	return CMD_SUCCESS;
}

/* vty login. */
DEFUN (vty_login,
       vty_login_cmd,
       "login",
       "Enable password checking\n")
{
	no_password_check = 0;
	return CMD_SUCCESS;
}

DEFUN (no_vty_login,
       no_vty_login_cmd,
       "no login",
       NO_STR
       "Enable password checking\n")
{
	no_password_check = 1;
	return CMD_SUCCESS;
}

DEFUN (service_advanced_vty,
       service_advanced_vty_cmd,
       "service advanced-vty",
       "Set up miscellaneous service\n"
       "Enable advanced mode vty interface\n")
{
	host.advanced = 1;
	return CMD_SUCCESS;
}

DEFUN (no_service_advanced_vty,
       no_service_advanced_vty_cmd,
       "no service advanced-vty",
       NO_STR
       "Set up miscellaneous service\n"
       "Enable advanced mode vty interface\n")
{
	host.advanced = 0;
	return CMD_SUCCESS;
}

DEFUN_NOSH(terminal_monitor,
	   terminal_monitor_cmd,
	   "terminal monitor [detach]",
	   "Set terminal line parameters\n"
	   "Copy debug output to the current terminal line\n"
	   "Keep logging feed open independent of VTY session\n")
{
	int fd_ret = -1;

	if (vty->type != VTY_SHELL_SERV) {
		vty_out(vty, "%% not supported\n");
		return CMD_WARNING;
	}

	if (argc == 3) {
		struct zlog_live_cfg detach_log = {};

		zlog_live_open(&detach_log, LOG_DEBUG, &fd_ret);
		zlog_live_disown(&detach_log);
	} else
		zlog_live_open(&vty->live_log, LOG_DEBUG, &fd_ret);

	if (fd_ret == -1) {
		vty_out(vty, "%% error opening live log: %m\n");
		return CMD_WARNING;
	}

	vty_pass_fd(vty, fd_ret);
	return CMD_SUCCESS;
}

DEFUN_NOSH(no_terminal_monitor,
	   no_terminal_monitor_cmd,
	   "no terminal monitor",
	   NO_STR
	   "Set terminal line parameters\n"
	   "Copy debug output to the current terminal line\n")
{
	zlog_live_close(&vty->live_log);
	return CMD_SUCCESS;
}

DEFUN_NOSH(terminal_no_monitor,
	   terminal_no_monitor_cmd,
	   "terminal no monitor",
	   "Set terminal line parameters\n"
	   NO_STR
	   "Copy debug output to the current terminal line\n")
{
	return no_terminal_monitor(self, vty, argc, argv);
}


DEFUN_NOSH (show_history,
       show_history_cmd,
       "show history",
       SHOW_STR
       "Display the session command history\n")
{
	int index;

	for (index = vty->hindex + 1; index != vty->hindex;) {
		if (index == VTY_MAXHIST) {
			index = 0;
			continue;
		}

		if (vty->hist[index] != NULL)
			vty_out(vty, "  %s\n", vty->hist[index]);

		index++;
	}

	return CMD_SUCCESS;
}

/* vty login. */
DEFPY (log_commands,
       log_commands_cmd,
       "[no] log commands",
       NO_STR
       "Logging control\n"
       "Log all commands\n")
{
	if (no) {
		if (vty_log_commands_perm) {
			vty_out(vty,
				"Daemon started with permanent logging turned on for commands, ignoring\n");
			return CMD_WARNING;
		}

		vty_log_commands = false;
	} else
		vty_log_commands = true;

	return CMD_SUCCESS;
}

/* Display current configuration. */
static int vty_config_write(struct vty *vty)
{
	vty_frame(vty, "line vty\n");

	if (vty_accesslist_name)
		vty_out(vty, " access-class %s\n", vty_accesslist_name);

	if (vty_ipv6_accesslist_name)
		vty_out(vty, " ipv6 access-class %s\n",
			vty_ipv6_accesslist_name);

	/* exec-timeout */
	if (vty_timeout_val != VTY_TIMEOUT_DEFAULT)
		vty_out(vty, " exec-timeout %ld %ld\n", vty_timeout_val / 60,
			vty_timeout_val % 60);

	/* login */
	if (no_password_check)
		vty_out(vty, " no login\n");

	vty_endframe(vty, "exit\n");

	if (vty_log_commands)
		vty_out(vty, "log commands\n");

	vty_out(vty, "!\n");

	return CMD_SUCCESS;
}

static int vty_config_write(struct vty *vty);
struct cmd_node vty_node = {
	.name = "vty",
	.node = VTY_NODE,
	.parent_node = CONFIG_NODE,
	.prompt = "%s(config-line)# ",
	.config_write = vty_config_write,
};

/* Reset all VTY status. */
void vty_reset(void)
{
	struct vty *vty;

	frr_each_safe (vtys, vty_sessions, vty) {
		buffer_reset(vty->lbuf);
		buffer_reset(vty->obuf);
		vty->status = VTY_CLOSE;
		vty_close(vty);
	}

	vty_timeout_val = VTY_TIMEOUT_DEFAULT;

	XFREE(MTYPE_VTY, vty_accesslist_name);
	XFREE(MTYPE_VTY, vty_ipv6_accesslist_name);
}

static void vty_save_cwd(void)
{
	char *c;

	c = getcwd(vty_cwd, sizeof(vty_cwd));

	if (!c) {
		/*
		 * At this point if these go wrong, more than likely
		 * the whole world is coming down around us
		 * Hence not worrying about it too much.
		 */
		if (chdir(SYSCONFDIR)) {
			flog_err_sys(EC_LIB_SYSTEM_CALL,
				     "Failure to chdir to %s, errno: %d",
				     SYSCONFDIR, errno);
			exit(-1);
		}
		if (getcwd(vty_cwd, sizeof(vty_cwd)) == NULL) {
			flog_err_sys(EC_LIB_SYSTEM_CALL,
				     "Failure to getcwd, errno: %d", errno);
			exit(-1);
		}
	}
}

char *vty_get_cwd(void)
{
	return vty_cwd;
}

int vty_shell(struct vty *vty)
{
	return vty->type == VTY_SHELL ? 1 : 0;
}

int vty_shell_serv(struct vty *vty)
{
	return vty->type == VTY_SHELL_SERV ? 1 : 0;
}

void vty_init_vtysh(void)
{
	/* currently nothing to do, but likely to have future use */
}


/*
 * These functions allow for CLI handling to be placed inside daemons; however,
 * currently they are only used by mgmtd, with mgmtd having each daemons CLI
 * functionality linked into it. This design choice was taken for efficiency.
 */

static void vty_mgmt_server_connected(struct mgmt_fe_client *client,
				      uintptr_t usr_data, bool connected)
{
	MGMTD_FE_CLIENT_DBG("Got %sconnected %s MGMTD Frontend Server",
			    !connected ? "dis: " : "",
			    !connected ? "from" : "to");

	/*
	 * We should not have any sessions for connecting or disconnecting case.
	 * The  fe client library will delete all session on disconnect before
	 * calling us.
	 */
	assert(mgmt_fe_client_session_count(client) == 0);

	mgmt_fe_connected = connected;

	/* Start or stop listening for vty connections */
	if (connected)
		frr_vty_serv_start();
	else
		frr_vty_serv_stop();
}

/*
 * A session has successfully been created for a vty.
 */
static void vty_mgmt_session_notify(struct mgmt_fe_client *client,
				    uintptr_t usr_data, uint64_t client_id,
				    bool create, bool success,
				    uintptr_t session_id, uintptr_t session_ctx)
{
	struct vty *vty;

	vty = (struct vty *)session_ctx;

	if (!success) {
		zlog_err("%s session for client %" PRIu64 " failed!",
			 create ? "Creating" : "Destroying", client_id);
		return;
	}

	MGMTD_FE_CLIENT_DBG("%s session for client %" PRIu64 " successfully",
			    create ? "Created" : "Destroyed", client_id);

	if (create) {
		assert(session_id != 0);
		vty->mgmt_session_id = session_id;
	} else {
		vty->mgmt_session_id = 0;
		/* We may come here by way of vty_close() and short-circuits */
		if (vty->status != VTY_CLOSE)
			vty_close(vty);
	}
}

static void vty_mgmt_ds_lock_notified(struct mgmt_fe_client *client,
				      uintptr_t usr_data, uint64_t client_id,
				      uintptr_t session_id,
				      uintptr_t session_ctx, uint64_t req_id,
				      bool lock_ds, bool success,
				      Mgmtd__DatastoreId ds_id,
				      char *errmsg_if_any)
{
	struct vty *vty;
	bool is_short_circuit = mgmt_fe_client_current_msg_short_circuit(client);

	vty = (struct vty *)session_ctx;

	assert(ds_id == MGMTD_DS_CANDIDATE || ds_id == MGMTD_DS_RUNNING);
	if (!success)
		zlog_err("%socking for DS %u failed, Err: '%s' vty %p",
			 lock_ds ? "L" : "Unl", ds_id, errmsg_if_any, vty);
	else {
		MGMTD_FE_CLIENT_DBG("%socked DS %u successfully",
				    lock_ds ? "L" : "Unl", ds_id);
		if (ds_id == MGMTD_DS_CANDIDATE)
			vty->mgmt_locked_candidate_ds = lock_ds;
		else
			vty->mgmt_locked_running_ds = lock_ds;
	}

	if (!is_short_circuit && vty->mgmt_req_pending_cmd) {
		assert(!strcmp(vty->mgmt_req_pending_cmd, "MESSAGE_LOCKDS_REQ"));
		vty_mgmt_resume_response(vty, success);
	}
}

static void vty_mgmt_set_config_result_notified(
	struct mgmt_fe_client *client, uintptr_t usr_data, uint64_t client_id,
	uintptr_t session_id, uintptr_t session_ctx, uint64_t req_id,
	bool success, Mgmtd__DatastoreId ds_id, bool implicit_commit,
	char *errmsg_if_any)
{
	struct vty *vty;

	vty = (struct vty *)session_ctx;

	if (!success) {
		zlog_err("SET_CONFIG request for client 0x%" PRIx64
			 " failed, Error: '%s'",
			 client_id, errmsg_if_any ? errmsg_if_any : "Unknown");
		vty_out(vty, "ERROR: SET_CONFIG request failed, Error: %s\n",
			errmsg_if_any ? errmsg_if_any : "Unknown");
	} else {
		MGMTD_FE_CLIENT_DBG("SET_CONFIG request for client 0x%" PRIx64
				    " req-id %" PRIu64 " was successfull",
				    client_id, req_id);
	}

	if (implicit_commit) {
		/* In this case the changes have been applied, we are done */
		vty_mgmt_unlock_candidate_inline(vty);
		vty_mgmt_unlock_running_inline(vty);
	}

	vty_mgmt_resume_response(vty, success);
}

static void vty_mgmt_commit_config_result_notified(
	struct mgmt_fe_client *client, uintptr_t usr_data, uint64_t client_id,
	uintptr_t session_id, uintptr_t session_ctx, uint64_t req_id,
	bool success, Mgmtd__DatastoreId src_ds_id,
	Mgmtd__DatastoreId dst_ds_id, bool validate_only, char *errmsg_if_any)
{
	struct vty *vty;

	vty = (struct vty *)session_ctx;

	if (!success) {
		zlog_err("COMMIT_CONFIG request for client 0x%" PRIx64
			 " failed, Error: '%s'",
			 client_id, errmsg_if_any ? errmsg_if_any : "Unknown");
		vty_out(vty, "ERROR: COMMIT_CONFIG request failed, Error: %s\n",
			errmsg_if_any ? errmsg_if_any : "Unknown");
	} else {
		MGMTD_FE_CLIENT_DBG(
			"COMMIT_CONFIG request for client 0x%" PRIx64
			" req-id %" PRIu64 " was successfull",
			client_id, req_id);
		if (errmsg_if_any)
			vty_out(vty, "MGMTD: %s\n", errmsg_if_any);
	}

	vty_mgmt_resume_response(vty, success);
}

static int vty_mgmt_get_data_result_notified(
	struct mgmt_fe_client *client, uintptr_t usr_data, uint64_t client_id,
	uintptr_t session_id, uintptr_t session_ctx, uint64_t req_id,
	bool success, Mgmtd__DatastoreId ds_id, Mgmtd__YangData **yang_data,
	size_t num_data, int next_key, char *errmsg_if_any)
{
	struct vty *vty;
	size_t indx;

	vty = (struct vty *)session_ctx;

	if (!success) {
		zlog_err("GET_DATA request for client 0x%" PRIx64
			 " failed, Error: '%s'",
			 client_id, errmsg_if_any ? errmsg_if_any : "Unknown");
		vty_out(vty, "ERROR: GET_DATA request failed, Error: %s\n",
			errmsg_if_any ? errmsg_if_any : "Unknown");
		vty_mgmt_resume_response(vty, success);
		return -1;
	}

	MGMTD_FE_CLIENT_DBG("GET_DATA request succeeded, client 0x%" PRIx64
			    " req-id %" PRIu64,
			    client_id, req_id);

	if (req_id != mgmt_last_req_id) {
		mgmt_last_req_id = req_id;
		vty_out(vty, "[\n");
	}

	for (indx = 0; indx < num_data; indx++) {
		vty_out(vty, "  \"%s\": \"%s\"\n", yang_data[indx]->xpath,
			yang_data[indx]->value->encoded_str_val);
	}
	if (next_key < 0) {
		vty_out(vty, "]\n");
		vty_mgmt_resume_response(vty, success);
	}

	return 0;
}

static struct mgmt_fe_client_cbs mgmt_cbs = {
	.client_connect_notify = vty_mgmt_server_connected,
	.client_session_notify = vty_mgmt_session_notify,
	.lock_ds_notify = vty_mgmt_ds_lock_notified,
	.set_config_notify = vty_mgmt_set_config_result_notified,
	.commit_config_notify = vty_mgmt_commit_config_result_notified,
	.get_data_notify = vty_mgmt_get_data_result_notified,
};

void vty_init_mgmt_fe(void)
{
	char name[40];

	assert(vty_master);
	assert(!mgmt_fe_client);
	snprintf(name, sizeof(name), "vty-%s-%ld", frr_get_progname(),
		 (long)getpid());
	mgmt_fe_client = mgmt_fe_client_create(name, &mgmt_cbs, 0, vty_master);
	assert(mgmt_fe_client);
}

bool vty_mgmt_fe_enabled(void)
{
	return mgmt_fe_client && mgmt_fe_connected;
}

bool vty_mgmt_should_process_cli_apply_changes(struct vty *vty)
{
	return vty->type != VTY_FILE && vty_mgmt_fe_enabled();
}

int vty_mgmt_send_lockds_req(struct vty *vty, Mgmtd__DatastoreId ds_id,
			     bool lock, bool scok)
{
	assert(mgmt_fe_client);
	assert(vty->mgmt_session_id);

	vty->mgmt_req_id++;
	if (mgmt_fe_send_lockds_req(mgmt_fe_client, vty->mgmt_session_id,
				    vty->mgmt_req_id, ds_id, lock, scok)) {
		zlog_err("Failed sending %sLOCK-DS-REQ req-id %" PRIu64,
			 lock ? "" : "UN", vty->mgmt_req_id);
		vty_out(vty, "Failed to send %sLOCK-DS-REQ to MGMTD!\n",
			lock ? "" : "UN");
		return -1;
	}

	if (!scok)
		vty->mgmt_req_pending_cmd = "MESSAGE_LOCKDS_REQ";

	return 0;
}

int vty_mgmt_send_config_data(struct vty *vty, bool implicit_commit)
{
	Mgmtd__YangDataValue value[VTY_MAXCFGCHANGES];
	Mgmtd__YangData cfg_data[VTY_MAXCFGCHANGES];
	Mgmtd__YangCfgDataReq cfg_req[VTY_MAXCFGCHANGES];
	Mgmtd__YangCfgDataReq *cfgreq[VTY_MAXCFGCHANGES] = {0};
	size_t indx;

	if (vty->type == VTY_FILE) {
		/*
		 * if this is a config file read we will not send any of the
		 * changes until we are done reading the file and have modified
		 * the local candidate DS.
		 */
		/* no-one else should be sending data right now */
		assert(!vty->mgmt_num_pending_setcfg);
		return 0;
	}

	/* If we are FE client and we have a vty then we have a session */
	assert(mgmt_fe_client && vty->mgmt_client_id && vty->mgmt_session_id);

	if (!vty->num_cfg_changes)
		return 0;

	/* grab the candidate and running lock prior to sending implicit commit
	 * command
	 */
	if (implicit_commit) {
		if (vty_mgmt_lock_candidate_inline(vty)) {
			vty_out(vty,
				"%% command failed, could not lock candidate DS\n");
			return -1;
		} else if (vty_mgmt_lock_running_inline(vty)) {
			vty_out(vty,
				"%% command failed, could not lock running DS\n");
			vty_mgmt_unlock_candidate_inline(vty);
			return -1;
		}
	}

	for (indx = 0; indx < vty->num_cfg_changes; indx++) {
		mgmt_yang_data_init(&cfg_data[indx]);

		if (vty->cfg_changes[indx].value) {
			mgmt_yang_data_value_init(&value[indx]);
			value[indx].encoded_str_val =
				(char *)vty->cfg_changes[indx].value;
			value[indx].value_case =
				MGMTD__YANG_DATA_VALUE__VALUE_ENCODED_STR_VAL;
			cfg_data[indx].value = &value[indx];
		}

		cfg_data[indx].xpath = vty->cfg_changes[indx].xpath;

		mgmt_yang_cfg_data_req_init(&cfg_req[indx]);
		cfg_req[indx].data = &cfg_data[indx];
		switch (vty->cfg_changes[indx].operation) {
		case NB_OP_DESTROY:
			cfg_req[indx].req_type =
				MGMTD__CFG_DATA_REQ_TYPE__DELETE_DATA;
			break;

		case NB_OP_CREATE:
		case NB_OP_MODIFY:
		case NB_OP_MOVE:
		case NB_OP_PRE_VALIDATE:
		case NB_OP_APPLY_FINISH:
			cfg_req[indx].req_type =
				MGMTD__CFG_DATA_REQ_TYPE__SET_DATA;
			break;
		case NB_OP_GET_ELEM:
		case NB_OP_GET_NEXT:
		case NB_OP_GET_KEYS:
		case NB_OP_LOOKUP_ENTRY:
		case NB_OP_RPC:
		default:
			assertf(false,
				"Invalid operation type for send config: %d",
				vty->cfg_changes[indx].operation);
			/*NOTREACHED*/
			abort();
		}

		cfgreq[indx] = &cfg_req[indx];
	}
	if (!indx)
		return 0;

	vty->mgmt_req_id++;
	if (mgmt_fe_send_setcfg_req(mgmt_fe_client, vty->mgmt_session_id,
				    vty->mgmt_req_id, MGMTD_DS_CANDIDATE,
				    cfgreq, indx, implicit_commit,
				    MGMTD_DS_RUNNING)) {
		zlog_err("Failed to send %zu config xpaths to mgmtd", indx);
		vty_out(vty, "%% Failed to send commands to mgmtd\n");
		return -1;
	}

	vty->mgmt_req_pending_cmd = "MESSAGE_SETCFG_REQ";

	return 0;
}

int vty_mgmt_send_commit_config(struct vty *vty, bool validate_only, bool abort)
{
	if (mgmt_fe_client && vty->mgmt_session_id) {
		vty->mgmt_req_id++;
		if (mgmt_fe_send_commitcfg_req(
			    mgmt_fe_client, vty->mgmt_session_id,
			    vty->mgmt_req_id, MGMTD_DS_CANDIDATE,
			    MGMTD_DS_RUNNING, validate_only, abort)) {
			zlog_err("Failed sending COMMIT-REQ req-id %" PRIu64,
				 vty->mgmt_req_id);
			vty_out(vty, "Failed to send COMMIT-REQ to MGMTD!\n");
			return -1;
		}

		vty->mgmt_req_pending_cmd = "MESSAGE_COMMCFG_REQ";
		vty->mgmt_num_pending_setcfg = 0;
	}

	return 0;
}

int vty_mgmt_send_get_req(struct vty *vty, bool is_config,
			  Mgmtd__DatastoreId datastore, const char **xpath_list,
			  int num_req)
{
	Mgmtd__YangData yang_data[VTY_MAXCFGCHANGES];
	Mgmtd__YangGetDataReq get_req[VTY_MAXCFGCHANGES];
	Mgmtd__YangGetDataReq *getreq[VTY_MAXCFGCHANGES];
	int i;

	vty->mgmt_req_id++;

	for (i = 0; i < num_req; i++) {
		mgmt_yang_get_data_req_init(&get_req[i]);
		mgmt_yang_data_init(&yang_data[i]);

		yang_data->xpath = (char *)xpath_list[i];

		get_req[i].data = &yang_data[i];
		getreq[i] = &get_req[i];
	}
	if (mgmt_fe_send_get_req(mgmt_fe_client, vty->mgmt_session_id,
				 vty->mgmt_req_id, is_config, datastore, getreq,
				 num_req)) {
		zlog_err("Failed to send GET- to MGMTD for req-id %" PRIu64 ".",
			 vty->mgmt_req_id);
		vty_out(vty, "Failed to send GET-CONFIG to MGMTD!\n");
		return -1;
	}

	vty->mgmt_req_pending_cmd = "MESSAGE_GETCFG_REQ";

	return 0;
}

/* Install vty's own commands like `who' command. */
void vty_init(struct event_loop *master_thread, bool do_command_logging)
{
	/* For further configuration read, preserve current directory. */
	vty_save_cwd();

	vty_master = master_thread;

	atexit(vty_stdio_atexit);

	/* Install bgp top node. */
	install_node(&vty_node);

	install_element(VIEW_NODE, &config_who_cmd);
	install_element(VIEW_NODE, &show_history_cmd);
	install_element(CONFIG_NODE, &line_vty_cmd);
	install_element(CONFIG_NODE, &service_advanced_vty_cmd);
	install_element(CONFIG_NODE, &no_service_advanced_vty_cmd);
	install_element(CONFIG_NODE, &show_history_cmd);
	install_element(CONFIG_NODE, &log_commands_cmd);

	if (do_command_logging) {
		vty_log_commands = true;
		vty_log_commands_perm = true;
	}

	install_element(ENABLE_NODE, &terminal_monitor_cmd);
	install_element(ENABLE_NODE, &terminal_no_monitor_cmd);
	install_element(ENABLE_NODE, &no_terminal_monitor_cmd);

	install_default(VTY_NODE);
	install_element(VTY_NODE, &exec_timeout_min_cmd);
	install_element(VTY_NODE, &exec_timeout_sec_cmd);
	install_element(VTY_NODE, &no_exec_timeout_cmd);
	install_element(VTY_NODE, &vty_access_class_cmd);
	install_element(VTY_NODE, &no_vty_access_class_cmd);
	install_element(VTY_NODE, &vty_login_cmd);
	install_element(VTY_NODE, &no_vty_login_cmd);
	install_element(VTY_NODE, &vty_ipv6_access_class_cmd);
	install_element(VTY_NODE, &no_vty_ipv6_access_class_cmd);
}

void vty_terminate(void)
{
	struct vty *vty;

	if (mgmt_fe_client) {
		mgmt_fe_client_destroy(mgmt_fe_client);
		mgmt_fe_client = 0;
	}

	memset(vty_cwd, 0x00, sizeof(vty_cwd));

	vty_reset();

	/* default state of vty_sessions is initialized & empty. */
	vtys_fini(vty_sessions);
	vtys_init(vty_sessions);

	/* vty_reset() doesn't close vtysh sessions */
	frr_each_safe (vtys, vtysh_sessions, vty) {
		buffer_reset(vty->lbuf);
		buffer_reset(vty->obuf);
		vty->status = VTY_CLOSE;
		vty_close(vty);
	}

	vtys_fini(vtysh_sessions);
	vtys_init(vtysh_sessions);

	vty_serv_stop();
}