Codebase list cyrus-sasl2 / lintian-fixes/main include / sasl.h
lintian-fixes/main

Tree @lintian-fixes/main (Download .tar.gz)

sasl.h @lintian-fixes/mainraw · history · blame

   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
/* This is a proposed C API for support of SASL
 *
 *********************************IMPORTANT*******************************
 * send email to chris.newman@innosoft.com and cyrus-bugs@andrew.cmu.edu *
 * if you need to add new error codes, callback types, property values,  *
 * etc.   It is important to keep the multiple implementations of this   *
 * API from diverging.                                                   *
 *********************************IMPORTANT*******************************
 *
 * Basic Type Summary:
 *  sasl_conn_t       Context for a SASL connection negotiation
 *  sasl_ssf_t        Security layer Strength Factor
 *  sasl_callback_t   A typed client/server callback function and context
 *  sasl_interact_t   A client interaction descriptor
 *  sasl_secret_t     A client password
 *  sasl_rand_t       Random data context structure
 *  sasl_security_properties_t  An application's required security level
 *
 * Callbacks:
 *  sasl_getopt_t     client/server: Get an option value
 *  sasl_logmsg_t     client/server: Log message handler
 *  sasl_getsimple_t  client: Get user/language list
 *  sasl_getsecret_t  client: Get authentication secret
 *  sasl_chalprompt_t client: Display challenge and prompt for response
 *
 * Server only Callbacks:
 *  sasl_authorize_t             user authorization policy callback
 *  sasl_getconfpath_t           get path to search for config file
 *  sasl_server_userdb_checkpass check password and auxprops in userdb
 *  sasl_server_userdb_setpass   set password in userdb
 *  sasl_server_canon_user       canonicalize username routine
 *
 * Client/Server Function Summary:
 *  sasl_done         Release all SASL global state
 *  sasl_dispose      Connection done: Dispose of sasl_conn_t
 *  sasl_getprop      Get property (e.g., user name, security layer info)
 *  sasl_setprop      Set property (e.g., external ssf)
 *  sasl_errdetail    Generate string from last error on connection
 *  sasl_errstring    Translate sasl error code to a string
 *  sasl_encode       Encode data to send using security layer
 *  sasl_decode       Decode data received using security layer
 *  
 * Utility functions:
 *  sasl_encode64     Encode data to send using MIME base64 encoding
 *  sasl_decode64     Decode data received using MIME base64 encoding
 *  sasl_erasebuffer  Erase a buffer
 *
 * Client Function Summary:
 *  sasl_client_init  Load and initialize client plug-ins (call once)
 *  sasl_client_new   Initialize client connection context: sasl_conn_t
 *  sasl_client_start Select mechanism for connection
 *  sasl_client_step  Perform one authentication step
 *
 * Server Function Summary
 *  sasl_server_init  Load and initialize server plug-ins (call once)
 *  sasl_server_new   Initialize server connection context: sasl_conn_t
 *  sasl_listmech     Create list of available mechanisms
 *  sasl_server_start Begin an authentication exchange
 *  sasl_server_step  Perform one authentication exchange step
 *  sasl_checkpass    Check a plaintext passphrase
 *  sasl_checkapop    Check an APOP challenge/response (uses pseudo "APOP"
 *                    mechanism similar to CRAM-MD5 mechanism; optional)
 *  sasl_user_exists  Check if user exists
 *  sasl_setpass      Change a password or add a user entry
 *  sasl_auxprop_request  Request auxiliary properties
 *  sasl_auxprop_getctx   Get auxiliary property context for connection
 *  sasl_auxprop_store    Store a set of auxiliary properties
 *
 * Basic client model:
 *  1. client calls sasl_client_init() at startup to load plug-ins
 *  2. when connection formed, call sasl_client_new()
 *  3. once list of supported mechanisms received from server, client
 *     calls sasl_client_start().  goto 4a
 *  4. client calls sasl_client_step()
 * [4a. If SASL_INTERACT, fill in prompts and goto 4
 *      -- doesn't happen if callbacks provided]
 *  4b. If SASL error, goto 7 or 3
 *  4c. If SASL_OK, continue or goto 6 if last server response was success
 *  5. send message to server, wait for response
 *  5a. On data or success with server response, goto 4
 *  5b. On failure goto 7 or 3
 *  5c. On success with no server response continue
 *  6. continue with application protocol until connection closes
 *     call sasl_getprop/sasl_encode/sasl_decode() if using security layer
 *  7. call sasl_dispose(), may return to step 2
 *  8. call sasl_done() when program terminates
 *
 * Basic Server model:
 *  1. call sasl_server_init() at startup to load plug-ins
 *  2. On connection, call sasl_server_new()
 *  3. call sasl_listmech() and send list to client]
 *  4. after client AUTH command, call sasl_server_start(), goto 5a
 *  5. call sasl_server_step()
 *  5a. If SASL_CONTINUE, output to client, wait response, repeat 5
 *  5b. If SASL error, then goto 7
 *  5c. If SASL_OK, move on
 *  6. continue with application protocol until connection closes
 *     call sasl_getprop to get username
 *     call sasl_getprop/sasl_encode/sasl_decode() if using security layer
 *  7. call sasl_dispose(), may return to step 2
 *  8. call sasl_done() when program terminates
 *
 *************************************************
 * IMPORTANT NOTE: server realms / username syntax
 *
 * If a user name contains a "@", then the rightmost "@" in the user name
 * separates the account name from the realm in which this account is
 * located.  A single server may support multiple realms.  If the
 * server knows the realm at connection creation time (e.g., a server
 * with multiple IP addresses tightly binds one address to a specific
 * realm) then that realm must be passed in the user_realm field of
 * the sasl_server_new call.  If user_realm is non-empty and an
 * unqualified user name is supplied, then the canon_user facility is
 * expected to append "@" and user_realm to the user name.  The canon_user
 * facility may treat other characters such as "%" as equivalent to "@".
 *
 * If the server forbids the use of "@" in user names for other
 * purposes, this simplifies security validation.
 */

#ifndef SASL_H
#define SASL_H 1

#include <stddef.h>  /* For size_t */

/* Keep in sync with win32/common.mak */
#define SASL_VERSION_MAJOR 2
#define SASL_VERSION_MINOR 1
#define SASL_VERSION_STEP 27

/* A convenience macro: same as was defined in the OpenLDAP LDAPDB */
#define SASL_VERSION_FULL ((SASL_VERSION_MAJOR << 16) |\
      (SASL_VERSION_MINOR << 8) | SASL_VERSION_STEP)

#include "prop.h"

/*************
 * Basic API *
 *************/

/* SASL result codes: */
#define SASL_CONTINUE    1   /* another step is needed in authentication */
#define SASL_OK          0   /* successful result */
#define SASL_FAIL       -1   /* generic failure */
#define SASL_NOMEM      -2   /* memory shortage failure */
#define SASL_BUFOVER    -3   /* overflowed buffer */
#define SASL_NOMECH     -4   /* mechanism not supported */
#define SASL_BADPROT    -5   /* bad protocol / cancel */
#define SASL_NOTDONE    -6   /* can't request info until later in exchange */
#define SASL_BADPARAM   -7   /* invalid parameter supplied */
#define SASL_TRYAGAIN   -8   /* transient failure (e.g., weak key) */
#define SASL_BADMAC	-9   /* integrity check failed */
#define SASL_NOTINIT    -12  /* SASL library not initialized */
                             /* -- client only codes -- */
#define SASL_INTERACT    2   /* needs user interaction */
#define SASL_BADSERV    -10  /* server failed mutual authentication step */
#define SASL_WRONGMECH  -11  /* mechanism doesn't support requested feature */
                             /* -- server only codes -- */
#define SASL_BADAUTH    -13  /* authentication failure */
#define SASL_NOAUTHZ    -14  /* authorization failure */
#define SASL_TOOWEAK    -15  /* mechanism too weak for this user */
#define SASL_ENCRYPT    -16  /* encryption needed to use mechanism */
#define SASL_TRANS      -17  /* One time use of a plaintext password will
				enable requested mechanism for user */
#define SASL_EXPIRED    -18  /* passphrase expired, has to be reset */
#define SASL_DISABLED   -19  /* account disabled */
#define SASL_NOUSER     -20  /* user not found */
#define SASL_BADVERS    -23  /* version mismatch with plug-in */
#define SASL_UNAVAIL    -24  /* remote authentication server unavailable */
#define SASL_NOVERIFY   -26  /* user exists, but no verifier for user */
			     /* -- codes for password setting -- */
#define SASL_PWLOCK     -21  /* passphrase locked */
#define SASL_NOCHANGE   -22  /* requested change was not needed */
#define SASL_WEAKPASS   -27  /* passphrase is too weak for security policy */
#define SASL_NOUSERPASS -28  /* user supplied passwords not permitted */
#define SASL_NEED_OLD_PASSWD -29 /* sasl_setpass needs old password in order
				    to perform password change */
#define SASL_CONSTRAINT_VIOLAT	-30 /* a property can't be stored,
				       because of some constrains/policy violation */

#define SASL_BADBINDING -32  /* channel binding failure */
#define SASL_CONFIGERR  -100 /* error when parsing configuration file */

/* max size of a sasl mechanism name */
#define SASL_MECHNAMEMAX 20

#ifdef _WIN32
/* Define to have the same layout as a WSABUF */
#ifndef STRUCT_IOVEC_DEFINED
#define STRUCT_IOVEC_DEFINED 1
struct iovec {
    long iov_len;
    char *iov_base;
};
#endif
#else
struct iovec;				     /* Defined in OS headers */
#endif


/* per-connection SASL negotiation state for client or server
 */
typedef struct sasl_conn sasl_conn_t;

/* Plain text password structure.
 *  len is the length of the password, data is the text.
 */
typedef struct sasl_secret {
    unsigned long len;
    unsigned char data[1];		/* variable sized */
} sasl_secret_t;

/* random data context structure
 */
typedef struct sasl_rand_s sasl_rand_t;

#ifdef __cplusplus
extern "C" {
#endif

/****************************
 * Configure Basic Services *
 ****************************/

/* the following functions are used to adjust how allocation and mutexes work
 * they must be called before all other SASL functions:
 */

#include <sys/types.h>

/* memory allocation functions which may optionally be replaced:
 */
typedef void *sasl_malloc_t(size_t);
typedef void *sasl_calloc_t(size_t, size_t);
typedef void *sasl_realloc_t(void *, size_t);
typedef void sasl_free_t(void *);

LIBSASL_API void sasl_set_alloc(sasl_malloc_t *,
				sasl_calloc_t *,
				sasl_realloc_t *,
				sasl_free_t *);

/* mutex functions which may optionally be replaced:
 *  sasl_mutex_alloc allocates a mutex structure
 *  sasl_mutex_lock blocks until mutex locked
 *   returns -1 on deadlock or parameter error
 *   returns 0 on success
 *  sasl_mutex_unlock unlocks mutex if it's locked
 *   returns -1 if not locked or parameter error
 *   returns 0 on success
 *  sasl_mutex_free frees a mutex structure
 */
typedef void *sasl_mutex_alloc_t(void);
typedef int sasl_mutex_lock_t(void *mutex);
typedef int sasl_mutex_unlock_t(void *mutex);
typedef void sasl_mutex_free_t(void *mutex);
LIBSASL_API void sasl_set_mutex(sasl_mutex_alloc_t *, sasl_mutex_lock_t *,
				sasl_mutex_unlock_t *, sasl_mutex_free_t *);

/*****************************
 * Security preference types *
 *****************************/

/* security layer strength factor -- an unsigned integer usable by the caller
 *  to specify approximate security layer strength desired.  Roughly
 *  correlated to effective key length for encryption.
 * 0   = no protection
 * 1   = integrity protection only
 * 40  = 40-bit DES or 40-bit RC2/RC4
 * 56  = DES
 * 112 = triple-DES
 * 128 = 128-bit RC2/RC4/BLOWFISH
 * 256 = baseline AES
 */
typedef unsigned sasl_ssf_t;

/* usage flags provided to sasl_server_new and sasl_client_new:
 */
#define SASL_SUCCESS_DATA    0x0004 /* server supports data on success */
#define SASL_NEED_PROXY      0x0008 /* require a mech that allows proxying */
#define SASL_NEED_HTTP       0x0010 /* require a mech that can do HTTP auth */

/***************************
 * Security Property Types *
 ***************************/

/* Structure specifying the client or server's security policy
 * and optional additional properties.
 */

/* These are the various security flags apps can specify. */
/* NOPLAINTEXT          -- don't permit mechanisms susceptible to simple
 *                         passive attack (e.g., PLAIN, LOGIN)
 * NOACTIVE             -- protection from active (non-dictionary) attacks
 *                         during authentication exchange.
 *                         Authenticates server.
 * NODICTIONARY         -- don't permit mechanisms susceptible to passive
 *                         dictionary attack
 * FORWARD_SECRECY      -- require forward secrecy between sessions
 *                         (breaking one won't help break next)
 * NOANONYMOUS          -- don't permit mechanisms that allow anonymous login
 * PASS_CREDENTIALS     -- require mechanisms which pass client
 *			   credentials, and allow mechanisms which can pass
 *			   credentials to do so
 * MUTUAL_AUTH          -- require mechanisms which provide mutual
 *			   authentication
 */
#define SASL_SEC_NOPLAINTEXT      0x0001
#define SASL_SEC_NOACTIVE         0x0002
#define SASL_SEC_NODICTIONARY     0x0004
#define SASL_SEC_FORWARD_SECRECY  0x0008
#define SASL_SEC_NOANONYMOUS      0x0010
#define SASL_SEC_PASS_CREDENTIALS 0x0020
#define SASL_SEC_MUTUAL_AUTH      0x0040
#define SASL_SEC_MAXIMUM          0x00FF

typedef struct sasl_security_properties 
{ 
    /* security strength factor
     *  min_ssf      = minimum acceptable final level
     *  max_ssf      = maximum acceptable final level
     */ 
    sasl_ssf_t min_ssf;
    sasl_ssf_t max_ssf;

    /* Maximum security layer receive buffer size.
     *  0=security layer not supported
     */
    unsigned maxbufsize; 
    
    /* bitfield for attacks to protect against */
    unsigned security_flags;

    /* NULL terminated array of additional property names, values */ 
    const char **property_names;
    const char **property_values;
} sasl_security_properties_t; 

/******************
 * Callback types *
 ******************/

/*
 * Extensible type for a client/server callbacks
 *  id      -- identifies callback type
 *  proc    -- procedure call arguments vary based on id
 *  context -- context passed to procedure
 */
/* Note that any memory that is allocated by the callback needs to be
 * freed by the application, be it via function call or interaction.
 *
 * It may be freed after sasl_*_step returns SASL_OK.  if the mechanism
 * requires this information to persist (for a security layer, for example)
 * it must maintain a private copy.
 */
typedef struct sasl_callback {
    /* Identifies the type of the callback function.
     * Mechanisms must ignore callbacks with id's they don't recognize.
     */
    unsigned long id;
    int (*proc)(void);   /* Callback function.  Types of arguments vary by 'id' */
    void *context;
} sasl_callback_t;

/* callback ids & functions:
 */
#define SASL_CB_LIST_END   0  /* end of list */

/* option reading callback -- this allows a SASL configuration to be
 *  encapsulated in the caller's configuration system.  Some implementations
 *  may use default config file(s) if this is omitted.  Configuration items
 *  may be plugin-specific and are arbitrary strings.
 *
 * inputs:
 *  context     -- option context from callback record
 *  plugin_name -- name of plugin (NULL = general SASL option)
 *  option      -- name of option
 * output:
 *  result      -- set to result which persists until next getopt in
 *                 same thread, unchanged if option not found
 *  len         -- length of result (may be NULL)
 * returns:
 *  SASL_OK     -- no error
 *  SASL_FAIL   -- error
 */
typedef int sasl_getopt_t(void *context, const char *plugin_name,
			  const char *option,
			  const char **result, unsigned *len);
#define SASL_CB_GETOPT       1

/* Logging levels for use with the logging callback function. */
#define SASL_LOG_NONE  0	/* don't log anything */
#define SASL_LOG_ERR   1	/* log unusual errors (default) */
#define SASL_LOG_FAIL  2	/* log all authentication failures */
#define SASL_LOG_WARN  3	/* log non-fatal warnings */
#define SASL_LOG_NOTE  4	/* more verbose than LOG_WARN */
#define SASL_LOG_DEBUG 5	/* more verbose than LOG_NOTE */
#define SASL_LOG_TRACE 6	/* traces of internal protocols */
#define SASL_LOG_PASS  7	/* traces of internal protocols, including
				 * passwords */

/* logging callback -- this allows plugins and the middleware to
 *  log operations they perform.
 * inputs:
 *  context     -- logging context from the callback record
 *  level       -- logging level; see above
 *  message     -- message to log
 * returns:
 *  SASL_OK     -- no error
 *  SASL_FAIL   -- error
 */
typedef int sasl_log_t(void *context,
		       int level,
		       const char *message);
#define SASL_CB_LOG	    2

/* getpath callback -- this allows applications to specify the
 * colon-separated path to search for plugins (by default,
 * taken from an implementation-specific location).
 * inputs:
 *  context     -- getpath context from the callback record
 * outputs:
 *  path	-- colon seperated path
 * returns:
 *  SASL_OK     -- no error
 *  SASL_FAIL   -- error
 */
typedef int sasl_getpath_t(void *context,
			   const char **path);

#define SASL_CB_GETPATH	    3

/* verify file callback -- this allows applications to check if they
 * want SASL to use files, file by file.  This is intended to allow
 * applications to sanity check the environment to make sure plugins
 * or the configuration file can't be written to, etc.
 * inputs: 
 *  context     -- verifypath context from the callback record
 *  file        -- full path to file to verify
 *  type        -- type of file to verify (see below)

 * returns:
 *  SASL_OK        -- no error (file can safely be used)
 *  SASL_CONTINUE  -- continue WITHOUT using this file
 *  SASL_FAIL      -- error 
 */

/* these are the types of files libsasl will ask about */
typedef enum {
    SASL_VRFY_PLUGIN=0,		/* a DLL/shared library plug-in */
    SASL_VRFY_CONF=1,		/* a configuration file */
    SASL_VRFY_PASSWD=2,		/* a password storage file/db */
    SASL_VRFY_OTHER=3		/* some other file */
} sasl_verify_type_t;

typedef int sasl_verifyfile_t(void *context,
                              const char *file, sasl_verify_type_t type);
#define SASL_CB_VERIFYFILE  4

/* getconfpath callback -- this allows applications to specify the
 * colon-separated path to search for config files (by default,
 * taken from the SASL_CONF_PATH environment variable).
 * inputs:
 *  context     -- getconfpath context from the callback record
 * outputs:
 *  path        -- colon seperated path (allocated on the heap; the
 *                 library will free it using the sasl_free_t *
 *                 passed to sasl_set_callback, or the standard free()
 *                 library call).
 * returns:
 *  SASL_OK     -- no error
 *  SASL_FAIL   -- error
 */
typedef int sasl_getconfpath_t(void *context,
                               char **path);

#define SASL_CB_GETCONFPATH  5

/* client/user interaction callbacks:
 */
/* Simple prompt -- result must persist until next call to getsimple on
 *  same connection or until connection context is disposed
 * inputs:
 *  context       -- context from callback structure
 *  id            -- callback id
 * outputs:
 *  result        -- set to NUL terminated string
 *                   NULL = user cancel
 *  len           -- length of result
 * returns SASL_OK
 */
typedef int sasl_getsimple_t(void *context, int id,
			     const char **result, unsigned *len);
#define SASL_CB_USER         0x4001  /* client user identity to login as */
#define SASL_CB_AUTHNAME     0x4002  /* client authentication name */
#define SASL_CB_LANGUAGE     0x4003  /* comma separated list of RFC 1766
			              * language codes in order of preference
				      * to be used to localize client prompts
				      * or server error codes */
#define SASL_CB_CNONCE       0x4007  /* caller supplies client-nonce
				      * primarily for testing purposes */

/* get a sasl_secret_t (plaintext password with length)
 * inputs:
 *  conn          -- connection context
 *  context       -- context from callback structure
 *  id            -- callback id
 * outputs:
 *  psecret       -- set to NULL to cancel
 *                   set to password structure which must persist until
 *                   next call to getsecret in same connection, but middleware
 *                   will erase password data when it's done with it.
 * returns SASL_OK
 */
typedef int sasl_getsecret_t(sasl_conn_t *conn, void *context, int id,
			     sasl_secret_t **psecret);
#define SASL_CB_PASS         0x4004  /* client passphrase-based secret */


/* prompt for input in response to a challenge.
 * input:
 *  context   -- context from callback structure
 *  id        -- callback id
 *  challenge -- server challenge
 * output:
 *  result    -- NUL terminated result, NULL = user cancel
 *  len       -- length of result
 * returns SASL_OK
 */
typedef int sasl_chalprompt_t(void *context, int id,
			      const char *challenge,
			      const char *prompt, const char *defresult,
			      const char **result, unsigned *len);
#define SASL_CB_ECHOPROMPT   0x4005 /* challenge and client enterred result */
#define SASL_CB_NOECHOPROMPT 0x4006 /* challenge and client enterred result */

/* prompt (or autoselect) the realm to do authentication in.
 *  may get a list of valid realms.
 * input:
 *  context     -- context from callback structure
 *  id          -- callback id
 *  availrealms -- available realms; string list; NULL terminated
 *                 list may be empty.
 * output:
 *  result      -- NUL terminated realm; NULL is equivalent to ""
 * returns SASL_OK
 * result must persist until the next callback
 */
typedef int sasl_getrealm_t(void *context, int id,
			    const char **availrealms,
			    const char **result);
#define SASL_CB_GETREALM (0x4008) /* realm to attempt authentication in */

/* server callbacks:
 */

/* improved callback to verify authorization;
 *     canonicalization now handled elsewhere
 *  conn           -- connection context
 *  requested_user -- the identity/username to authorize (NUL terminated)
 *  rlen           -- length of requested_user
 *  auth_identity  -- the identity associated with the secret (NUL terminated)
 *  alen           -- length of auth_identity
 *  default_realm  -- default user realm, as passed to sasl_server_new if
 *  urlen          -- length of default realm
 *  propctx        -- auxiliary properties
 * returns SASL_OK on success,
 *         SASL_NOAUTHZ or other SASL response on failure
 */
typedef int sasl_authorize_t(sasl_conn_t *conn,
			     void *context,
			     const char *requested_user, unsigned rlen,
			     const char *auth_identity, unsigned alen,
			     const char *def_realm, unsigned urlen,
			     struct propctx *propctx);
#define SASL_CB_PROXY_POLICY 0x8001

/* functions for "userdb" based plugins to call to get/set passwords.
 * the location for the passwords is determined by the caller or middleware.
 * plug-ins may get passwords from other locations.
 */

/* callback to verify a plaintext password against the caller-supplied
 * user database.  This is necessary to allow additional <method>s for
 * encoding of the userPassword property.
 *  user          -- NUL terminated user name with user@realm syntax
 *  pass          -- password to check (may not be NUL terminated)
 *  passlen       -- length of password to check
 *  propctx       -- auxiliary properties for user
 */
typedef int sasl_server_userdb_checkpass_t(sasl_conn_t *conn,
					   void *context,
					   const char *user,
					   const char *pass,
					   unsigned passlen,
					   struct propctx *propctx);
#define SASL_CB_SERVER_USERDB_CHECKPASS (0x8005)

/* callback to store/change a plaintext password in the user database
 *  user          -- NUL terminated user name with user@realm syntax
 *  pass          -- password to store (may not be NUL terminated)
 *  passlen       -- length of password to store
 *  propctx       -- auxiliary properties (not stored)
 *  flags         -- see SASL_SET_* flags below (SASL_SET_CREATE optional)
 */
typedef int sasl_server_userdb_setpass_t(sasl_conn_t *conn,
					 void *context,
					 const char *user,
					 const char *pass,
					 unsigned passlen,
					 struct propctx *propctx,
					 unsigned flags);
#define SASL_CB_SERVER_USERDB_SETPASS (0x8006)

/* callback for a server-supplied user canonicalization function.
 *
 * This function is called directly after the mechanism has the
 * authentication and authorization IDs.  It is called before any
 * User Canonicalization plugin is called.  It has the responsibility
 * of copying its output into the provided output buffers.
 * 
 *  in, inlen     -- user name to canonicalize, may not be NUL terminated
 *                   may be same buffer as out
 *  flags         -- not currently used, supplied by auth mechanism
 *  user_realm    -- the user realm (may be NULL in case of client)
 *  out           -- buffer to copy user name
 *  out_max       -- max length of user name
 *  out_len       -- set to length of user name
 *
 * returns
 *  SASL_OK         on success
 *  SASL_BADPROT    username contains invalid character
 */

/* User Canonicalization Function Flags */

#define SASL_CU_NONE    0x00 /* Not a valid flag to pass */
/* One of the following two is required */
#define SASL_CU_AUTHID  0x01
#define SASL_CU_AUTHZID 0x02

/* Combine the following with SASL_CU_AUTHID, if you don't want
   to fail if auxprop returned SASL_NOUSER/SASL_NOMECH. */
#define SASL_CU_EXTERNALLY_VERIFIED 0x04

#define SASL_CU_OVERRIDE	    0x08    /* mapped to SASL_AUXPROP_OVERRIDE */

/* The following CU flags are passed "as is" down to auxprop lookup */
#define SASL_CU_ASIS_MASK	    0xFFF0
/* NOTE: Keep in sync with SASL_AUXPROP_<XXX> flags */
#define SASL_CU_VERIFY_AGAINST_HASH 0x10


typedef int sasl_canon_user_t(sasl_conn_t *conn,
			      void *context,
			      const char *in, unsigned inlen,
			      unsigned flags,
			      const char *user_realm,
			      char *out,
			      unsigned out_max, unsigned *out_len);

#define SASL_CB_CANON_USER (0x8007)

/**********************************
 * Common Client/server functions *
 **********************************/

/* Types of paths to set (see sasl_set_path below). */
#define SASL_PATH_TYPE_PLUGIN	0
#define SASL_PATH_TYPE_CONFIG	1

/* a simpler way to set plugin path or configuration file path
 * without the need to set sasl_getpath_t callback.
 *
 * This function can be called before sasl_server_init/sasl_client_init.
 */  
LIBSASL_API int sasl_set_path (int path_type, char * path);

/* get sasl library version information
 * implementation is a vendor-defined string
 * version is a vender-defined representation of the version #.
 *
 * This function is being deprecated in favor of sasl_version_info. */
LIBSASL_API void sasl_version(const char **implementation,
			      int *version);

/* Extended version of sasl_version().
 *
 * This function is to be used
 *  for library version display and logging
 *  for bug workarounds in old library versions
 *
 * The sasl_version_info is not to be used for API feature detection.
 *
 * All parameters are optional. If NULL is specified, the value is not returned.
 */
LIBSASL_API void sasl_version_info (const char **implementation,
				const char **version_string,
				int *version_major,
				int *version_minor,
				int *version_step,
				int *version_patch);

/* dispose of all SASL plugins.  Connection
 * states have to be disposed of before calling this.
 *
 * This function is DEPRECATED in favour of sasl_server_done/
 * sasl_client_done.
 */
LIBSASL_API void sasl_done(void);

/* dispose of all SASL plugins.  Connection
 * states have to be disposed of before calling this.
 * This function should be called instead of sasl_done(),
   whenever possible.
 */
LIBSASL_API int sasl_server_done(void);

/* dispose of all SASL plugins.  Connection
 * states have to be disposed of before calling this.
 * This function should be called instead of sasl_done(),
   whenever possible.
 */
LIBSASL_API int sasl_client_done(void);

/* dispose connection state, sets it to NULL
 *  checks for pointer to NULL
 */
LIBSASL_API void sasl_dispose(sasl_conn_t **pconn);

/* translate an error number into a string
 * input:
 *  saslerr  -- the error number
 *  langlist -- comma separated list of RFC 1766 languages (may be NULL)
 * results:
 *  outlang  -- the language actually used (may be NULL if don't care)
 * returns:
 *  the error message in UTF-8 (only the US-ASCII subset if langlist is NULL)
 */
LIBSASL_API const char *sasl_errstring(int saslerr,
				       const char *langlist,
				       const char **outlang);

/* get detail about the last error that occurred on a connection
 * text is sanitized so it's suitable to send over the wire
 * (e.g., no distinction between SASL_BADAUTH and SASL_NOUSER)
 * input:
 *  conn          -- mandatory connection context
 * returns:
 *  the error message in UTF-8 (only the US-ASCII subset permitted if no
 *  SASL_CB_LANGUAGE callback is present)
 */
LIBSASL_API const char *sasl_errdetail(sasl_conn_t *conn);

/* set the error string which will be returned by sasl_errdetail() using
 *  syslog()-style formatting (e.g. printf-style with %m as most recent
 *  errno error)
 *
 *  primarily for use by server callbacks such as the sasl_authorize_t
 *  callback and internally to plug-ins
 *
 * This will also trigger a call to the SASL logging callback (if any)
 * with a level of SASL_LOG_FAIL unless the SASL_NOLOG flag is set.
 *
 * Messages should be sensitive to the current language setting.  If there
 * is no SASL_CB_LANGUAGE callback messages MUST be US-ASCII otherwise UTF-8
 * is used and use of RFC 2482 for mixed-language text is encouraged.
 *
 * if conn is NULL, function does nothing
 */
LIBSASL_API void sasl_seterror(sasl_conn_t *conn, unsigned flags,
			       const char *fmt, ...);
#define SASL_NOLOG       0x01
			   
/* get property from SASL connection state
 *  propnum       -- property number
 *  pvalue        -- pointer to value
 * returns:
 *  SASL_OK       -- no error
 *  SASL_NOTDONE  -- property not available yet
 *  SASL_BADPARAM -- bad property number
 */
LIBSASL_API int sasl_getprop(sasl_conn_t *conn, int propnum,
			     const void **pvalue);
#define SASL_USERNAME     0	/* pointer to NUL terminated user name */
#define SASL_SSF          1	/* security layer security strength factor,
                                 * if 0, call to sasl_encode, sasl_decode
                                 * unnecessary */
#define SASL_MAXOUTBUF    2     /* security layer max output buf unsigned */  
#define SASL_DEFUSERREALM 3	/* default realm passed to server_new */
				/* or set with setprop */
#define SASL_GETOPTCTX    4	/* context for getopt callback */
#define SASL_CALLBACK     7	/* current callback function list */
#define SASL_IPLOCALPORT  8	/* iplocalport string passed to server_new */
#define SASL_IPREMOTEPORT 9	/* ipremoteport string passed to server_new */

/* This returns a string which is either empty or has an error message
 * from sasl_seterror (e.g., from a plug-in or callback).  It differs
 * from the result of sasl_errdetail() which also takes into account the
 * last return status code.
 */
#define SASL_PLUGERR     10

/* a handle to any delegated credentials or NULL if none is present 
 * is returned by the mechanism. The user will probably need to know
 * which mechanism was used to actually known how to make use of them
 * currently only implemented for the gssapi mechanism */
#define SASL_DELEGATEDCREDS 11

#define SASL_SERVICE      12	/* service passed to sasl_*_new */
#define SASL_SERVERFQDN   13	/* serverFQDN passed to sasl_*_new */
#define SASL_AUTHSOURCE   14	/* name of auth source last used, useful
				 * for failed authentication tracking */
#define SASL_MECHNAME     15    /* active mechanism name, if any */
#define SASL_AUTHUSER     16    /* authentication/admin user */
#define SASL_APPNAME	  17	/* application name (used for logging/
				   configuration), same as appname parameter
				   to sasl_server_init */

/* GSS-API credential handle for sasl_client_step() or sasl_server_step().
 * The application is responsible for releasing this credential handle. */
#define	SASL_GSS_CREDS	  18

/* GSS name (gss_name_t) of the peer, as output by gss_inquire_context()
 * or gss_accept_sec_context().
 * On server end this is similar to SASL_USERNAME, but the gss_name_t
 * structure can contain additional attributes associated with the peer.
 */
#define	SASL_GSS_PEER_NAME	19

/* Local GSS name (gss_name_t) as output by gss_inquire_context(). This
 * is particularly useful for servers that respond to multiple names. */
#define	SASL_GSS_LOCAL_NAME	20

/* Channel binding information. Memory is managed by the caller. */
typedef struct sasl_channel_binding {
    const char *name;
    int critical;
    unsigned long len;
    const unsigned char *data;
} sasl_channel_binding_t;

#define SASL_CHANNEL_BINDING    21

/* HTTP Request (RFC 2616) - ONLY used for HTTP Digest Auth (RFC 2617) */
typedef struct sasl_http_request {
    const char *method;			/* HTTP Method */
    const char *uri;			/* request-URI */
    const unsigned char *entity;	/* entity-body */
    unsigned long elen;			/* entity-body length */
    unsigned non_persist;		/* Is it a non-persistent connection? */
} sasl_http_request_t;

#define SASL_HTTP_REQUEST	22

/* set property in SASL connection state
 * returns:
 *  SASL_OK       -- value set
 *  SASL_BADPARAM -- invalid property or value
 */
LIBSASL_API int sasl_setprop(sasl_conn_t *conn,
			     int propnum,
			     const void *value);
#define SASL_SSF_EXTERNAL  100	/* external SSF active (sasl_ssf_t *) */
#define SASL_SEC_PROPS     101	/* sasl_security_properties_t */
#define SASL_AUTH_EXTERNAL 102	/* external authentication ID (const char *) */

/* If the SASL_AUTH_EXTERNAL value is non-NULL, then a special version of the
 * EXTERNAL mechanism is enabled (one for server-embedded EXTERNAL mechanisms).
 * Otherwise, the EXTERNAL mechanism will be absent unless a plug-in
 * including EXTERNAL is present.
 */

/* do precalculations during an idle period or network round trip
 *  may pass NULL to precompute for some mechanisms prior to connect
 *  returns 1 if action taken, 0 if no action taken
 */
LIBSASL_API int sasl_idle(sasl_conn_t *conn);

/**************
 * Client API *
 **************/

/* list of client interactions with user for caller to fill in
 */
typedef struct sasl_interact {
    unsigned long id;		/* same as client/user callback ID */
    const char *challenge;	/* presented to user (e.g. OTP challenge) */
    const char *prompt;		/* presented to user (e.g. "Username: ") */
    const char *defresult;	/* default result string */
    const void *result;		/* set to point to result */
    unsigned len;		/* set to length of result */
} sasl_interact_t;

/* initialize the SASL client drivers
 *  callbacks      -- base callbacks for all client connections;
 *                    must include getopt callback
 * returns:
 *  SASL_OK        -- Success
 *  SASL_NOMEM     -- Not enough memory
 *  SASL_BADVERS   -- Mechanism version mismatch
 *  SASL_BADPARAM  -- missing getopt callback or error in config file
 *  SASL_NOMECH    -- No mechanisms available
 *  ...
 */
LIBSASL_API int sasl_client_init(const sasl_callback_t *callbacks);

/* initialize a client exchange based on the specified mechanism
 *  service       -- registered name of the service using SASL (e.g. "imap")
 *  serverFQDN    -- the fully qualified domain name of the server
 *  iplocalport   -- client IPv4/IPv6 domain literal string with port
 *                    (if NULL, then mechanisms requiring IPaddr are disabled)
 *  ipremoteport  -- server IPv4/IPv6 domain literal string with port
 *                    (if NULL, then mechanisms requiring IPaddr are disabled)
 *  prompt_supp   -- list of client interactions supported
 *                   may also include sasl_getopt_t context & call
 *                   NULL prompt_supp = user/pass via SASL_INTERACT only
 *                   NULL proc = interaction supported via SASL_INTERACT
 *  flags         -- server usage flags (see above)
 * in/out:
 *  pconn         -- connection negotiation structure
 *                   pointer to NULL => allocate new
 *
 * Returns:
 *  SASL_OK       -- success
 *  SASL_NOMECH   -- no mechanism meets requested properties
 *  SASL_NOMEM    -- not enough memory
 */
LIBSASL_API int sasl_client_new(const char *service,
				const char *serverFQDN,
				const char *iplocalport,
				const char *ipremoteport,
				const sasl_callback_t *prompt_supp,
				unsigned flags,
				sasl_conn_t **pconn);

/* select a mechanism for a connection
 *  mechlist      -- mechanisms server has available (punctuation ignored)
 *                   if NULL, then discard cached info and retry last mech
 * output:
 *  prompt_need   -- on SASL_INTERACT, list of prompts needed to continue
 *                   may be NULL if callbacks provided
 *  clientout     -- the initial client response to send to the server
 *                   will be valid until next call to client_start/client_step
 *                   NULL if mech doesn't include initial client challenge
 *  mech          -- set to mechansm name of selected mechanism (may be NULL)
 *
 * Returns:
 *  SASL_OK       -- success
 *  SASL_NOMEM    -- not enough memory
 *  SASL_NOMECH   -- no mechanism meets requested properties
 *  SASL_INTERACT -- user interaction needed to fill in prompt_need list
 */
LIBSASL_API int sasl_client_start(sasl_conn_t *conn,
				  const char *mechlist,
				  sasl_interact_t **prompt_need,
				  const char **clientout,
				  unsigned *clientoutlen,
				  const char **mech);

/* do a single authentication step.
 *  serverin    -- the server message received by the client, MUST have a NUL
 *                 sentinel, not counted by serverinlen
 * output:
 *  prompt_need -- on SASL_INTERACT, list of prompts needed to continue
 *  clientout   -- the client response to send to the server
 *                 will be valid until next call to client_start/client_step
 *
 * returns:
 *  SASL_OK        -- success
 *  SASL_INTERACT  -- user interaction needed to fill in prompt_need list
 *  SASL_BADPROT   -- server protocol incorrect/cancelled
 *  SASL_BADSERV   -- server failed mutual auth
 */
LIBSASL_API int sasl_client_step(sasl_conn_t *conn,
				 const char *serverin,
				 unsigned serverinlen,
				 sasl_interact_t **prompt_need,
				 const char **clientout,
				 unsigned *clientoutlen);

/**************
 * Server API *
 **************/

/* initialize server drivers, done once per process
 *  callbacks      -- callbacks for all server connections; must include
 *                    getopt callback
 *  appname        -- name of calling application (for lower level logging)
 * results:
 *  state          -- server state
 * returns:
 *  SASL_OK        -- success
 *  SASL_BADPARAM  -- error in config file
 *  SASL_NOMEM     -- memory failure
 *  SASL_BADVERS   -- Mechanism version mismatch
 */
LIBSASL_API int sasl_server_init(const sasl_callback_t *callbacks,
				 const char *appname);

/* IP/port syntax:
 *  a.b.c.d;p              where a-d are 0-255 and p is 0-65535 port number.
 *  e:f:g:h:i:j:k:l;p      where e-l are 0000-ffff lower-case hexidecimal
 *  e:f:g:h:i:j:a.b.c.d;p  alternate syntax for previous
 *
 *  Note that one or more "0" fields in f-k can be replaced with "::"
 *  Thus:                 e:f:0000:0000:0000:j:k:l;p
 *  can be abbreviated:   e:f::j:k:l;p
 *
 * A buffer of size 52 is adequate for the longest format with NUL terminator.
 */

/* create context for a single SASL connection
 *  service        -- registered name of the service using SASL (e.g. "imap")
 *  serverFQDN     -- Fully qualified domain name of server.  NULL means use
 *                    gethostname() or equivalent.
 *                    Useful for multi-homed servers.
 *  user_realm     -- permits multiple user realms on server, NULL = default
 *  iplocalport    -- server IPv4/IPv6 domain literal string with port
 *                    (if NULL, then mechanisms requiring IPaddr are disabled)
 *  ipremoteport   -- client IPv4/IPv6 domain literal string with port
 *                    (if NULL, then mechanisms requiring IPaddr are disabled)
 *  callbacks      -- callbacks (e.g., authorization, lang, new getopt context)
 *  flags          -- usage flags (see above)
 * returns:
 *  pconn          -- new connection context
 *
 * returns:
 *  SASL_OK        -- success
 *  SASL_NOMEM     -- not enough memory
 */
LIBSASL_API int sasl_server_new(const char *service,
				const char *serverFQDN,
				const char *user_realm,
				const char *iplocalport,
				const char *ipremoteport,
				const sasl_callback_t *callbacks,
				unsigned flags,
				sasl_conn_t **pconn);

/* Return an array of NUL-terminated strings, terminated by a NULL pointer,
 * which lists all possible mechanisms that the library can supply
 *
 * Returns NULL on failure. */
LIBSASL_API const char ** sasl_global_listmech(void);

/* This returns a list of mechanisms in a NUL-terminated string
 *  conn          -- the connection to list mechanisms for (either client
 *                   or server)
 *  user          -- restricts mechanisms to those available to that user
 *                   (may be NULL, not used for client case)
 *  prefix        -- appended to beginning of result
 *  sep           -- appended between mechanisms
 *  suffix        -- appended to end of result
 * results:
 *  result        -- NUL terminated result which persists until next
 *                   call to sasl_listmech for this sasl_conn_t
 *  plen          -- gets length of result (excluding NUL), may be NULL
 *  pcount        -- gets number of mechanisms, may be NULL
 *
 * returns:
 *  SASL_OK        -- success
 *  SASL_NOMEM     -- not enough memory
 *  SASL_NOMECH    -- no enabled mechanisms
 */
LIBSASL_API int sasl_listmech(sasl_conn_t *conn,
			      const char *user,
			      const char *prefix,
			      const char *sep,
			      const char *suffix,
			      const char **result,
			      unsigned *plen,
			      int *pcount);

/* start a mechanism exchange within a connection context
 *  mech           -- the mechanism name client requested
 *  clientin       -- client initial response (NUL terminated), NULL if empty
 *  clientinlen    -- length of initial response
 *  serverout      -- initial server challenge, NULL if done 
 *                    (library handles freeing this string)
 *  serveroutlen   -- length of initial server challenge
 * output:
 *  pconn          -- the connection negotiation state on success
 *
 * Same returns as sasl_server_step() or
 * SASL_NOMECH if mechanism not available.
 */
LIBSASL_API int sasl_server_start(sasl_conn_t *conn,
				  const char *mech,
				  const char *clientin,
				  unsigned clientinlen,
				  const char **serverout,
				  unsigned *serveroutlen);

/* perform one step of the SASL exchange
 *  inputlen & input -- client data
 *                      NULL on first step if no optional client step
 *  outputlen & output -- set to the server data to transmit
 *                        to the client in the next step
 *                        (library handles freeing this)
 *
 * returns:
 *  SASL_OK        -- exchange is complete.
 *  SASL_CONTINUE  -- indicates another step is necessary.
 *  SASL_TRANS     -- entry for user exists, but not for mechanism
 *                    and transition is possible
 *  SASL_BADPARAM  -- service name needed
 *  SASL_BADPROT   -- invalid input from client
 *  ...
 */
LIBSASL_API int sasl_server_step(sasl_conn_t *conn,
				 const char *clientin,
				 unsigned clientinlen,
				 const char **serverout,
				 unsigned *serveroutlen);

/* check if an apop exchange is valid
 *  (note this is an optional part of the SASL API)
 *  if challenge is NULL, just check if APOP is enabled
 * inputs:
 *  challenge     -- challenge which was sent to client
 *  challen       -- length of challenge, 0 = strlen(challenge)
 *  response      -- client response, "<user> <digest>" (RFC 1939)
 *  resplen       -- length of response, 0 = strlen(response)
 * returns 
 *  SASL_OK       -- success
 *  SASL_BADAUTH  -- authentication failed
 *  SASL_BADPARAM -- missing challenge
 *  SASL_BADPROT  -- protocol error (e.g., response in wrong format)
 *  SASL_NOVERIFY -- user found, but no verifier
 *  SASL_NOMECH   -- mechanism not supported
 *  SASL_NOUSER   -- user not found
 */
LIBSASL_API int sasl_checkapop(sasl_conn_t *conn,
			       const char *challenge, unsigned challen,
			       const char *response, unsigned resplen);

/* check if a plaintext password is valid
 *   if user is NULL, check if plaintext passwords are enabled
 * inputs:
 *  user          -- user to query in current user_domain
 *  userlen       -- length of username, 0 = strlen(user)
 *  pass          -- plaintext password to check
 *  passlen       -- length of password, 0 = strlen(pass)
 * returns 
 *  SASL_OK       -- success
 *  SASL_NOMECH   -- mechanism not supported
 *  SASL_NOVERIFY -- user found, but no verifier
 *  SASL_NOUSER   -- user not found
 */
LIBSASL_API int sasl_checkpass(sasl_conn_t *conn,
			       const char *user, unsigned userlen,
			       const char *pass, unsigned passlen);

/* check if a user exists on server
 *  conn          -- connection context
 *  service       -- registered name of the service using SASL (e.g. "imap")
 *  user_realm    -- permits multiple user realms on server, NULL = default
 *  user          -- NUL terminated user name
 *
 * returns:
 *  SASL_OK       -- success
 *  SASL_DISABLED -- account disabled
 *  SASL_NOUSER   -- user not found
 *  SASL_NOVERIFY -- user found, but no usable mechanism
 *  SASL_NOMECH   -- no mechanisms enabled
 *  SASL_UNAVAIL  -- remote authentication server unavailable, try again later
 */
LIBSASL_API int sasl_user_exists(sasl_conn_t *conn,
				 const char *service,
				 const char *user_realm,
				 const char *user);

/* set the password for a user
 *  conn        -- SASL connection
 *  user        -- user name
 *  pass        -- plaintext password, may be NULL to remove user
 *  passlen     -- length of password, 0 = strlen(pass)
 *  oldpass     -- NULL will sometimes work
 *  oldpasslen  -- length of password, 0 = strlen(oldpass)
 *  flags       -- see flags below
 * 
 * returns:
 *  SASL_NOCHANGE  -- proper entry already exists
 *  SASL_NOMECH    -- no authdb supports password setting as configured
 *  SASL_NOVERIFY  -- user exists, but no settable password present
 *  SASL_DISABLED  -- account disabled
 *  SASL_PWLOCK    -- password locked
 *  SASL_WEAKPASS  -- password too weak for security policy
 *  SASL_NOUSERPASS -- user-supplied passwords not permitted
 *  SASL_FAIL      -- OS error
 *  SASL_BADPARAM  -- password too long
 *  SASL_OK        -- successful
 */
LIBSASL_API int sasl_setpass(sasl_conn_t *conn,
			     const char *user,
			     const char *pass, unsigned passlen,
			     const char *oldpass, unsigned oldpasslen,
			     unsigned flags);
#define SASL_SET_CREATE  0x01   /* create a new entry for user */
#define SASL_SET_DISABLE 0x02	/* disable user account */
#define SASL_SET_NOPLAIN 0x04	/* do not store secret in plain text */
#define SASL_SET_CURMECH_ONLY 0x08	/* set the mechanism specific password only.
					   fail if no current mechanism */

/*********************************************************
 * Auxiliary Property Support -- added by cjn 1999-09-29 *
 *********************************************************/

#define SASL_AUX_END      NULL	/* last auxiliary property */

#define SASL_AUX_ALL "*" /* A special flag to signal user deletion */

/* traditional Posix items (should be implemented on Posix systems) */
#define SASL_AUX_PASSWORD_PROP "userPassword" /* User Password */
#define SASL_AUX_PASSWORD "*" SASL_AUX_PASSWORD_PROP /* User Password (of authid) */
#define SASL_AUX_UIDNUM   "uidNumber"	/* UID number for the user */
#define SASL_AUX_GIDNUM   "gidNumber"	/* GID for the user */
#define SASL_AUX_FULLNAME "gecos"	/* full name of the user, unix-style */
#define SASL_AUX_HOMEDIR  "homeDirectory" /* home directory for user */
#define SASL_AUX_SHELL    "loginShell"	/* login shell for the user */

/* optional additional items (not necessarily implemented) */
/* single preferred mail address for user canonically-quoted
 * RFC821/822 syntax */
#define SASL_AUX_MAILADDR "mail"
/* path to unix-style mailbox for user */
#define SASL_AUX_UNIXMBX  "mailMessageStore"
/* SMTP mail channel name to use if user authenticates successfully */
#define SASL_AUX_MAILCHAN "mailSMTPSubmitChannel"

/* Request a set of auxiliary properties
 *  conn         connection context
 *  propnames    list of auxiliary property names to request ending with
 *               NULL.  
 *
 * Subsequent calls will add items to the request list.  Call with NULL
 * to clear the request list.
 *
 * errors
 *  SASL_OK       -- success
 *  SASL_BADPARAM -- bad count/conn parameter
 *  SASL_NOMEM    -- out of memory
 */
LIBSASL_API int sasl_auxprop_request(sasl_conn_t *conn,
				     const char **propnames);

/* Returns current auxiliary property context.
 * Use functions in prop.h to access content
 *
 *  if authentication hasn't completed, property values may be empty/NULL
 *
 *  properties not recognized by active plug-ins will be left empty/NULL
 *
 *  returns NULL if conn is invalid.
 */
LIBSASL_API struct propctx *sasl_auxprop_getctx(sasl_conn_t *conn);

/* Store the set of auxiliary properties for the given user.
 * Use functions in prop.h to set the content.
 *
 *  conn         connection context
 *  ctx          property context from prop_new()/prop_request()/prop_set()
 *  user         NUL terminated user
 *
 * Call with NULL 'ctx' to see if the backend allows storing properties.
 *
 * errors
 *  SASL_OK       -- success
 *  SASL_NOMECH   -- can not store some/all properties
 *  SASL_BADPARAM -- bad conn/ctx/user parameter
 *  SASL_NOMEM    -- out of memory
 *  SASL_FAIL     -- failed to store
 */
LIBSASL_API int sasl_auxprop_store(sasl_conn_t *conn,
				   struct propctx *ctx, const char *user);

/**********************
 * security layer API *
 **********************/

/* encode a block of data for transmission using security layer,
 *  returning the input buffer if there is no security layer.
 *  output is only valid until next call to sasl_encode or sasl_encodev
 * returns:
 *  SASL_OK      -- success (returns input if no layer negotiated)
 *  SASL_NOTDONE -- security layer negotiation not finished
 *  SASL_BADPARAM -- inputlen is greater than the SASL_MAXOUTBUF
 */
LIBSASL_API int sasl_encode(sasl_conn_t *conn,
			    const char *input, unsigned inputlen,
			    const char **output, unsigned *outputlen);

/* encode a block of data for transmission using security layer
 *  output is only valid until next call to sasl_encode or sasl_encodev
 * returns:
 *  SASL_OK      -- success (returns input if no layer negotiated)
 *  SASL_NOTDONE -- security layer negotiation not finished
 *  SASL_BADPARAM -- input length is greater than the SASL_MAXOUTBUF
 *		     or no security layer
 */
LIBSASL_API int sasl_encodev(sasl_conn_t *conn,
			     const struct iovec *invec, unsigned numiov,
			     const char **output, unsigned *outputlen);

/* decode a block of data received using security layer
 *  returning the input buffer if there is no security layer.
 *  output is only valid until next call to sasl_decode
 *
 *  if outputlen is 0 on return, than the value of output is undefined.
 *  
 * returns:
 *  SASL_OK      -- success (returns input if no layer negotiated)
 *  SASL_NOTDONE -- security layer negotiation not finished
 *  SASL_BADMAC  -- bad message integrity check
 */
LIBSASL_API int sasl_decode(sasl_conn_t *conn,
			    const char *input, unsigned inputlen,
			    const char **output, unsigned *outputlen);

#ifdef __cplusplus
}
#endif

#endif /* SASL_H */