summaryrefslogtreecommitdiffstats
path: root/security/nss/lib/util/utilmod.c
blob: 7d3fcda819f52165d5bbdee5f9185b67f0b357c0 (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
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/*
 * The following code handles the storage of PKCS 11 modules used by the
 * NSS. For the rest of NSS, only one kind of database handle exists:
 *
 *     SFTKDBHandle
 *
 * There is one SFTKDBHandle for each key database and one for each cert
 * database. These databases are opened as associated pairs, one pair per
 * slot. SFTKDBHandles are reference counted objects.
 *
 * Each SFTKDBHandle points to a low level database handle (SDB). This handle
 * represents the underlying physical database. These objects are not
 * reference counted, and are 'owned' by their respective SFTKDBHandles.
 */

#include "prprf.h"
#include "prsystem.h"
#include "secport.h"
#include "utilpars.h"
#include "secerr.h"

#if defined(_WIN32)
#include <io.h>
#include <windows.h>
#endif
#ifdef XP_UNIX
#include <unistd.h>
#endif

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#if defined(_WIN32)
#define os_fdopen _fdopen
#define os_truncate_open_flags _O_CREAT | _O_RDWR | _O_TRUNC
#define os_append_open_flags _O_CREAT | _O_RDWR | _O_APPEND
#define os_open_permissions_type int
#define os_open_permissions_default _S_IREAD | _S_IWRITE
#define os_stat_type struct _stat

/*
 * Convert a UTF8 string to Unicode wide character
 */
LPWSTR
_NSSUTIL_UTF8ToWide(const char *buf)
{
    DWORD size;
    LPWSTR wide;

    if (!buf) {
        return NULL;
    }

    size = MultiByteToWideChar(CP_UTF8, 0, buf, -1, NULL, 0);
    if (size == 0) {
        return NULL;
    }
    wide = PORT_Alloc(sizeof(WCHAR) * size);
    if (!wide) {
        return NULL;
    }
    size = MultiByteToWideChar(CP_UTF8, 0, buf, -1, wide, size);
    if (size == 0) {
        PORT_Free(wide);
        return NULL;
    }
    return wide;
}

static int
os_open(const char *filename, int oflag, int pmode)
{
    int fd;

    if (!filename) {
        return -1;
    }

    wchar_t *filenameWide = _NSSUTIL_UTF8ToWide(filename);
    if (!filenameWide) {
        return -1;
    }
    fd = _wopen(filenameWide, oflag, pmode);
    PORT_Free(filenameWide);

    return fd;
}

static int
os_stat(const char *path, os_stat_type *buffer)
{
    int result;

    if (!path) {
        return -1;
    }

    wchar_t *pathWide = _NSSUTIL_UTF8ToWide(path);
    if (!pathWide) {
        return -1;
    }
    result = _wstat(pathWide, buffer);
    PORT_Free(pathWide);

    return result;
}

static FILE *
os_fopen(const char *filename, const char *mode)
{
    FILE *fp;

    if (!filename || !mode) {
        return NULL;
    }

    wchar_t *filenameWide = _NSSUTIL_UTF8ToWide(filename);
    if (!filenameWide) {
        return NULL;
    }
    wchar_t *modeWide = _NSSUTIL_UTF8ToWide(mode);
    if (!modeWide) {
        PORT_Free(filenameWide);
        return NULL;
    }
    fp = _wfopen(filenameWide, modeWide);
    PORT_Free(filenameWide);
    PORT_Free(modeWide);

    return fp;
}

PRStatus
_NSSUTIL_Access(const char *path, PRAccessHow how)
{
    int result;

    if (!path) {
        return PR_FAILURE;
    }

    int mode;
    switch (how) {
        case PR_ACCESS_WRITE_OK:
            mode = 2;
            break;
        case PR_ACCESS_READ_OK:
            mode = 4;
            break;
        case PR_ACCESS_EXISTS:
            mode = 0;
            break;
        default:
            return PR_FAILURE;
    }

    wchar_t *pathWide = _NSSUTIL_UTF8ToWide(path);
    if (!pathWide) {
        return PR_FAILURE;
    }
    result = _waccess(pathWide, mode);
    PORT_Free(pathWide);

    return result < 0 ? PR_FAILURE : PR_SUCCESS;
}

static PRStatus
nssutil_Delete(const char *name)
{
    BOOL result;

    if (!name) {
        return PR_FAILURE;
    }

    wchar_t *nameWide = _NSSUTIL_UTF8ToWide(name);
    if (!nameWide) {
        return PR_FAILURE;
    }
    result = DeleteFileW(nameWide);
    PORT_Free(nameWide);

    return result ? PR_SUCCESS : PR_FAILURE;
}

static PRStatus
nssutil_Rename(const char *from, const char *to)
{
    BOOL result;

    if (!from || !to) {
        return PR_FAILURE;
    }

    wchar_t *fromWide = _NSSUTIL_UTF8ToWide(from);
    if (!fromWide) {
        return PR_FAILURE;
    }
    wchar_t *toWide = _NSSUTIL_UTF8ToWide(to);
    if (!toWide) {
        PORT_Free(fromWide);
        return PR_FAILURE;
    }
    result = MoveFileW(fromWide, toWide);
    PORT_Free(fromWide);
    PORT_Free(toWide);

    return result ? PR_SUCCESS : PR_FAILURE;
}
#else
#define os_fopen fopen
#define os_open open
#define os_fdopen fdopen
#define os_stat stat
#define os_truncate_open_flags O_CREAT | O_RDWR | O_TRUNC
#define os_append_open_flags O_CREAT | O_RDWR | O_APPEND
#define os_open_permissions_type mode_t
#define os_open_permissions_default 0600
#define os_stat_type struct stat
#define nssutil_Delete PR_Delete
#define nssutil_Rename PR_Rename
#endif

/****************************************************************
 *
 * Secmod database.
 *
 * The new secmod database is simply a text file with each of the module
 * entries in the following form:
 *
 * #
 * # This is a comment The next line is the library to load
 * library=libmypkcs11.so
 * name="My PKCS#11 module"
 * params="my library's param string"
 * nss="NSS parameters"
 * other="parameters for other libraries and applications"
 *
 * library=libmynextpk11.so
 * name="My other PKCS#11 module"
 */

/*
 * Smart string cat functions. Automatically manage the memory.
 * The first parameter is the destination string. If it's null, we
 * allocate memory for it. If it's not, we reallocate memory
 * so the the concanenated string fits.
 */
static char *
nssutil_DupnCat(char *baseString, const char *str, int str_len)
{
    int baseStringLen = baseString ? PORT_Strlen(baseString) : 0;
    int len = baseStringLen + 1;
    char *newString;

    len += str_len;
    newString = (char *)PORT_Realloc(baseString, len);
    if (newString == NULL) {
        PORT_Free(baseString);
        return NULL;
    }
    PORT_Memcpy(&newString[baseStringLen], str, str_len);
    newString[len - 1] = 0;
    return newString;
}

/* Same as nssutil_DupnCat except it concatenates the full string, not a
 * partial one */
static char *
nssutil_DupCat(char *baseString, const char *str)
{
    return nssutil_DupnCat(baseString, str, PORT_Strlen(str));
}

/* function to free up all the memory associated with a null terminated
 * array of module specs */
static SECStatus
nssutil_releaseSpecList(char **moduleSpecList)
{
    if (moduleSpecList) {
        char **index;
        for (index = moduleSpecList; *index; index++) {
            PORT_Free(*index);
        }
        PORT_Free(moduleSpecList);
    }
    return SECSuccess;
}

#define SECMOD_STEP 10
static SECStatus
nssutil_growList(char ***pModuleList, int *useCount, int last)
{
    char **newModuleList;

    *useCount += SECMOD_STEP;
    newModuleList = (char **)PORT_Realloc(*pModuleList,
                                          *useCount * sizeof(char *));
    if (newModuleList == NULL) {
        return SECFailure;
    }
    PORT_Memset(&newModuleList[last], 0, sizeof(char *) * SECMOD_STEP);
    *pModuleList = newModuleList;
    return SECSuccess;
}

static char *
_NSSUTIL_GetOldSecmodName(const char *dbname, const char *filename)
{
    char *file = NULL;
    char *dirPath = PORT_Strdup(dbname);
    char *sep;

    sep = PORT_Strrchr(dirPath, *NSSUTIL_PATH_SEPARATOR);
#ifdef _WIN32
    if (!sep) {
        /* utilparst.h defines NSSUTIL_PATH_SEPARATOR as "/" for all
         * platforms. */
        sep = PORT_Strrchr(dirPath, '\\');
    }
#endif
    if (sep) {
        *sep = 0;
        file = PR_smprintf("%s" NSSUTIL_PATH_SEPARATOR "%s", dirPath, filename);
    } else {
        file = PR_smprintf("%s", filename);
    }
    PORT_Free(dirPath);
    return file;
}

static SECStatus nssutil_AddSecmodDBEntry(const char *appName,
                                          const char *filename,
                                          const char *dbname,
                                          const char *module, PRBool rw);

enum lfopen_mode { lfopen_truncate,
                   lfopen_append };

FILE *
lfopen(const char *name, enum lfopen_mode om, os_open_permissions_type open_perms)
{
    int fd;
    FILE *file;

    fd = os_open(name,
                 (om == lfopen_truncate) ? os_truncate_open_flags : os_append_open_flags,
                 open_perms);
    if (fd < 0) {
        return NULL;
    }
    file = os_fdopen(fd, (om == lfopen_truncate) ? "w+" : "a+");
    if (!file) {
        close(fd);
    }
    /* file inherits fd */
    return file;
}

#define MAX_LINE_LENGTH 2048

/*
 * Read all the existing modules in out of the file.
 */
static char **
nssutil_ReadSecmodDB(const char *appName,
                     const char *filename, const char *dbname,
                     char *params, PRBool rw)
{
    FILE *fd = NULL;
    char **moduleList = NULL;
    int moduleCount = 1;
    int useCount = SECMOD_STEP;
    char line[MAX_LINE_LENGTH];
    PRBool internal = PR_FALSE;
    PRBool skipParams = PR_FALSE;
    char *moduleString = NULL;
    char *paramsValue = NULL;
    PRBool failed = PR_TRUE;

    moduleList = (char **)PORT_ZAlloc(useCount * sizeof(char *));
    if (moduleList == NULL)
        return NULL;

    if (dbname == NULL) {
        goto return_default;
    }

    /* do we really want to use streams here */
    fd = os_fopen(dbname, "r");
    if (fd == NULL)
        goto done;

    /*
     * the following loop takes line separated config lines and collapses
     * the lines to a single string, escaping and quoting as necessary.
     */
    /* loop state variables */
    moduleString = NULL;   /* current concatenated string */
    internal = PR_FALSE;   /* is this an internal module */
    skipParams = PR_FALSE; /* did we find an override parameter block*/
    paramsValue = NULL;    /* the current parameter block value */
    do {
        int len;

        if (fgets(line, sizeof(line), fd) == NULL) {
            goto endloop;
        }

        /* remove the ending newline */
        len = PORT_Strlen(line);
        if (len && line[len - 1] == '\n') {
            len--;
            line[len] = 0;
        }
        if (*line == '#') {
            continue;
        }
        if (*line != 0) {
            /*
             * The PKCS #11 group standard assumes blocks of strings
             * separated by new lines, clumped by new lines. Internally
             * we take strings separated by spaces, so we may need to escape
             * certain spaces.
             */
            char *value = PORT_Strchr(line, '=');

            /* there is no value, write out the stanza as is */
            if (value == NULL || value[1] == 0) {
                if (moduleString) {
                    moduleString = nssutil_DupnCat(moduleString, " ", 1);
                    if (moduleString == NULL)
                        goto loser;
                }
                moduleString = nssutil_DupCat(moduleString, line);
                if (moduleString == NULL)
                    goto loser;
                /* value is already quoted, just write it out */
            } else if (value[1] == '"') {
                if (moduleString) {
                    moduleString = nssutil_DupnCat(moduleString, " ", 1);
                    if (moduleString == NULL)
                        goto loser;
                }
                moduleString = nssutil_DupCat(moduleString, line);
                if (moduleString == NULL)
                    goto loser;
                /* we have an override parameter section, remember that
                 * we found this (see following comment about why this
                 * is necessary). */
                if (PORT_Strncasecmp(line, "parameters", 10) == 0) {
                    skipParams = PR_TRUE;
                }
                /*
                 * The internal token always overrides it's parameter block
                 * from the passed in parameters, so wait until then end
                 * before we include the parameter block in case we need to
                 * override it. NOTE: if the parameter block is quoted with ("),
                 * this override does not happen. This allows you to override
                 * the application's parameter configuration.
                 *
                 * parameter block state is controlled by the following variables:
                 *  skipParams - Bool : set to true of we have an override param
                 *    block (all other blocks, either implicit or explicit are
                 *    ignored).
                 *  paramsValue - char * : pointer to the current param block. In
                 *    the absence of overrides, paramsValue is set to the first
                 *    parameter block we find. All subsequent blocks are ignored.
                 *    When we find an internal token, the application passed
                 *    parameters take precident.
                 */
            } else if (PORT_Strncasecmp(line, "parameters", 10) == 0) {
                /* already have parameters */
                if (paramsValue) {
                    continue;
                }
                paramsValue = NSSUTIL_Quote(&value[1], '"');
                if (paramsValue == NULL)
                    goto loser;
                continue;
            } else {
                /* may need to quote */
                char *newLine;
                if (moduleString) {
                    moduleString = nssutil_DupnCat(moduleString, " ", 1);
                    if (moduleString == NULL)
                        goto loser;
                }
                moduleString = nssutil_DupnCat(moduleString, line, value - line + 1);
                if (moduleString == NULL)
                    goto loser;
                newLine = NSSUTIL_Quote(&value[1], '"');
                if (newLine == NULL)
                    goto loser;
                moduleString = nssutil_DupCat(moduleString, newLine);
                PORT_Free(newLine);
                if (moduleString == NULL)
                    goto loser;
            }

            /* check to see if it's internal? */
            if (PORT_Strncasecmp(line, "NSS=", 4) == 0) {
                /* This should be case insensitive! reviewers make
                 * me fix it if it's not */
                if (PORT_Strstr(line, "internal")) {
                    internal = PR_TRUE;
                    /* override the parameters */
                    if (paramsValue) {
                        PORT_Free(paramsValue);
                    }
                    paramsValue = NSSUTIL_Quote(params, '"');
                }
            }
            continue;
        }
        if ((moduleString == NULL) || (*moduleString == 0)) {
            continue;
        }

    endloop:
        /*
         * if we are here, we have found a complete stanza. Now write out
         * any param section we may have found.
         */
        if (paramsValue) {
            /* we had an override */
            if (!skipParams) {
                moduleString = nssutil_DupnCat(moduleString, " parameters=", 12);
                if (moduleString == NULL)
                    goto loser;
                moduleString = nssutil_DupCat(moduleString, paramsValue);
                if (moduleString == NULL)
                    goto loser;
            }
            PORT_Free(paramsValue);
            paramsValue = NULL;
        }

        if ((moduleCount + 1) >= useCount) {
            SECStatus rv;
            rv = nssutil_growList(&moduleList, &useCount, moduleCount + 1);
            if (rv != SECSuccess) {
                goto loser;
            }
        }

        if (internal) {
            moduleList[0] = moduleString;
        } else {
            moduleList[moduleCount] = moduleString;
            moduleCount++;
        }
        moduleString = NULL;
        internal = PR_FALSE;
        skipParams = PR_FALSE;
    } while (!feof(fd));

    if (moduleString) {
        PORT_Free(moduleString);
        moduleString = NULL;
    }
done:
    /* if we couldn't open a pkcs11 database, look for the old one */
    if (fd == NULL) {
        char *olddbname = _NSSUTIL_GetOldSecmodName(dbname, filename);
        PRStatus status;

        /* couldn't get the old name */
        if (!olddbname) {
            goto bail;
        }

        /* old one exists */
        status = _NSSUTIL_Access(olddbname, PR_ACCESS_EXISTS);
        if (status == PR_SUCCESS) {
            PR_smprintf_free(olddbname);
            PORT_ZFree(moduleList, useCount * sizeof(char *));
            PORT_SetError(SEC_ERROR_LEGACY_DATABASE);
            return NULL;
        }

    bail:
        if (olddbname) {
            PR_smprintf_free(olddbname);
        }
    }

return_default:

    if (!moduleList[0]) {
        char *newParams;
        moduleString = PORT_Strdup(NSSUTIL_DEFAULT_INTERNAL_INIT1);
        newParams = NSSUTIL_Quote(params, '"');
        if (newParams == NULL)
            goto loser;
        moduleString = nssutil_DupCat(moduleString, newParams);
        PORT_Free(newParams);
        if (moduleString == NULL)
            goto loser;
        moduleString = nssutil_DupCat(moduleString,
                                      NSSUTIL_DEFAULT_INTERNAL_INIT2);
        if (moduleString == NULL)
            goto loser;
        moduleString = nssutil_DupCat(moduleString,
                                      NSSUTIL_DEFAULT_SFTKN_FLAGS);
        if (moduleString == NULL)
            goto loser;
        moduleString = nssutil_DupCat(moduleString,
                                      NSSUTIL_DEFAULT_INTERNAL_INIT3);
        if (moduleString == NULL)
            goto loser;
        moduleList[0] = moduleString;
        moduleString = NULL;
    }
    failed = PR_FALSE;

loser:
    /*
     * cleanup
     */
    /* deal with trust cert db here */
    if (moduleString) {
        PORT_Free(moduleString);
        moduleString = NULL;
    }
    if (paramsValue) {
        PORT_Free(paramsValue);
        paramsValue = NULL;
    }
    if (failed || (moduleList[0] == NULL)) {
        /* This is wrong! FIXME */
        nssutil_releaseSpecList(moduleList);
        moduleList = NULL;
        failed = PR_TRUE;
    }
    if (fd != NULL) {
        fclose(fd);
    } else if (!failed && rw) {
        /* update our internal module */
        nssutil_AddSecmodDBEntry(appName, filename, dbname, moduleList[0], rw);
    }
    return moduleList;
}

static SECStatus
nssutil_ReleaseSecmodDBData(const char *appName,
                            const char *filename, const char *dbname,
                            char **moduleSpecList, PRBool rw)
{
    if (moduleSpecList) {
        nssutil_releaseSpecList(moduleSpecList);
    }
    return SECSuccess;
}

/*
 * Delete a module from the Data Base
 */
static SECStatus
nssutil_DeleteSecmodDBEntry(const char *appName,
                            const char *filename,
                            const char *dbname,
                            const char *args,
                            PRBool rw)
{
    /* SHDB_FIXME implement */
    os_stat_type stat_existing;
    os_open_permissions_type file_mode;
    FILE *fd = NULL;
    FILE *fd2 = NULL;
    char line[MAX_LINE_LENGTH];
    char *dbname2 = NULL;
    char *block = NULL;
    char *name = NULL;
    char *lib = NULL;
    int name_len = 0, lib_len = 0;
    PRBool skip = PR_FALSE;
    PRBool found = PR_FALSE;

    if (dbname == NULL) {
        PORT_SetError(SEC_ERROR_INVALID_ARGS);
        return SECFailure;
    }

    if (!rw) {
        PORT_SetError(SEC_ERROR_READ_ONLY);
        return SECFailure;
    }

    dbname2 = PORT_Strdup(dbname);
    if (dbname2 == NULL)
        goto loser;
    dbname2[strlen(dbname) - 1]++;

    /* get the permissions of the existing file, or use the default */
    if (!os_stat(dbname, &stat_existing)) {
        file_mode = stat_existing.st_mode;
    } else {
        file_mode = os_open_permissions_default;
    }

    /* do we really want to use streams here */
    fd = os_fopen(dbname, "r");
    if (fd == NULL)
        goto loser;

    fd2 = lfopen(dbname2, lfopen_truncate, file_mode);

    if (fd2 == NULL)
        goto loser;

    name = NSSUTIL_ArgGetParamValue("name", args);
    if (name) {
        name_len = PORT_Strlen(name);
    }
    lib = NSSUTIL_ArgGetParamValue("library", args);
    if (lib) {
        lib_len = PORT_Strlen(lib);
    }

    /*
     * the following loop takes line separated config files and collapses
     * the lines to a single string, escaping and quoting as necessary.
     */
    /* loop state variables */
    block = NULL;
    skip = PR_FALSE;
    while (fgets(line, sizeof(line), fd) != NULL) {
        /* If we are processing a block (we haven't hit a blank line yet */
        if (*line != '\n') {
            /* skip means we are in the middle of a block we are deleting */
            if (skip) {
                continue;
            }
            /* if we haven't found the block yet, check to see if this block
             * matches our requirements */
            if (!found && ((name && (PORT_Strncasecmp(line, "name=", 5) == 0) &&
                            (PORT_Strncmp(line + 5, name, name_len) == 0)) ||
                           (lib && (PORT_Strncasecmp(line, "library=", 8) == 0) &&
                            (PORT_Strncmp(line + 8, lib, lib_len) == 0)))) {

                /* yup, we don't need to save any more data, */
                PORT_Free(block);
                block = NULL;
                /* we don't need to collect more of this block */
                skip = PR_TRUE;
                /* we don't need to continue searching for the block */
                found = PR_TRUE;
                continue;
            }
            /* not our match, continue to collect data in this block */
            block = nssutil_DupCat(block, line);
            continue;
        }
        /* we've collected a block of data that wasn't the module we were
         * looking for, write it out */
        if (block) {
            fwrite(block, PORT_Strlen(block), 1, fd2);
            PORT_Free(block);
            block = NULL;
        }
        /* If we didn't just delete the this block, keep the blank line */
        if (!skip) {
            fputs(line, fd2);
        }
        /* we are definately not in a deleted block anymore */
        skip = PR_FALSE;
    }
    fclose(fd);
    fclose(fd2);
    if (found) {
        /* rename dbname2 to dbname */
        nssutil_Delete(dbname);
        nssutil_Rename(dbname2, dbname);
    } else {
        nssutil_Delete(dbname2);
    }
    PORT_Free(dbname2);
    PORT_Free(lib);
    PORT_Free(name);
    PORT_Free(block);
    return SECSuccess;

loser:
    if (fd != NULL) {
        fclose(fd);
    }
    if (fd2 != NULL) {
        fclose(fd2);
    }
    if (dbname2) {
        nssutil_Delete(dbname2);
        PORT_Free(dbname2);
    }
    PORT_Free(lib);
    PORT_Free(name);
    return SECFailure;
}

/*
 * Add a module to the Data base
 */
static SECStatus
nssutil_AddSecmodDBEntry(const char *appName,
                         const char *filename, const char *dbname,
                         const char *module, PRBool rw)
{
    os_stat_type stat_existing;
    os_open_permissions_type file_mode;
    FILE *fd = NULL;
    char *block = NULL;
    PRBool libFound = PR_FALSE;

    if (dbname == NULL) {
        PORT_SetError(SEC_ERROR_INVALID_ARGS);
        return SECFailure;
    }

    /* can't write to a read only module */
    if (!rw) {
        PORT_SetError(SEC_ERROR_READ_ONLY);
        return SECFailure;
    }

    /* remove the previous version if it exists */
    (void)nssutil_DeleteSecmodDBEntry(appName, filename, dbname, module, rw);

    /* get the permissions of the existing file, or use the default */
    if (!os_stat(dbname, &stat_existing)) {
        file_mode = stat_existing.st_mode;
    } else {
        file_mode = os_open_permissions_default;
    }

    fd = lfopen(dbname, lfopen_append, file_mode);
    if (fd == NULL) {
        return SECFailure;
    }
    module = NSSUTIL_ArgStrip(module);
    while (*module) {
        int count;
        char *keyEnd = PORT_Strchr(module, '=');
        char *value;

        if (PORT_Strncmp(module, "library=", 8) == 0) {
            libFound = PR_TRUE;
        }
        if (keyEnd == NULL) {
            block = nssutil_DupCat(block, module);
            break;
        }
        block = nssutil_DupnCat(block, module, keyEnd - module + 1);
        if (block == NULL) {
            goto loser;
        }
        value = NSSUTIL_ArgFetchValue(&keyEnd[1], &count);
        if (value) {
            block = nssutil_DupCat(block, NSSUTIL_ArgStrip(value));
            PORT_Free(value);
        }
        if (block == NULL) {
            goto loser;
        }
        block = nssutil_DupnCat(block, "\n", 1);
        module = keyEnd + 1 + count;
        module = NSSUTIL_ArgStrip(module);
    }
    if (block) {
        if (!libFound) {
            fprintf(fd, "library=\n");
        }
        fwrite(block, PORT_Strlen(block), 1, fd);
        fprintf(fd, "\n");
        PORT_Free(block);
        block = NULL;
    }
    fclose(fd);
    return SECSuccess;

loser:
    PORT_Free(block);
    fclose(fd);
    return SECFailure;
}

char **
NSSUTIL_DoModuleDBFunction(unsigned long function, char *parameters, void *args)
{
    char *secmod = NULL;
    char *appName = NULL;
    char *filename = NULL;
    NSSDBType dbType = NSS_DB_TYPE_NONE;
    PRBool rw;
    static char *success = "Success";
    char **rvstr = NULL;

    secmod = _NSSUTIL_GetSecmodName(parameters, &dbType, &appName,
                                    &filename, &rw);
    if ((dbType == NSS_DB_TYPE_LEGACY) ||
        (dbType == NSS_DB_TYPE_MULTIACCESS)) {
        /* we can't handle the old database, only softoken can */
        PORT_SetError(SEC_ERROR_LEGACY_DATABASE);
        rvstr = NULL;
        goto done;
    }

    switch (function) {
        case SECMOD_MODULE_DB_FUNCTION_FIND:
            rvstr = nssutil_ReadSecmodDB(appName, filename,
                                         secmod, (char *)parameters, rw);
            break;
        case SECMOD_MODULE_DB_FUNCTION_ADD:
            rvstr = (nssutil_AddSecmodDBEntry(appName, filename,
                                              secmod, (char *)args, rw) == SECSuccess)
                        ? &success
                        : NULL;
            break;
        case SECMOD_MODULE_DB_FUNCTION_DEL:
            rvstr = (nssutil_DeleteSecmodDBEntry(appName, filename,
                                                 secmod, (char *)args, rw) == SECSuccess)
                        ? &success
                        : NULL;
            break;
        case SECMOD_MODULE_DB_FUNCTION_RELEASE:
            rvstr = (nssutil_ReleaseSecmodDBData(appName, filename,
                                                 secmod, (char **)args, rw) == SECSuccess)
                        ? &success
                        : NULL;
            break;
    }
done:
    if (secmod)
        PR_smprintf_free(secmod);
    if (appName)
        PORT_Free(appName);
    if (filename)
        PORT_Free(filename);
    return rvstr;
}