summaryrefslogtreecommitdiffstats
path: root/security/nss/lib/ssl/sslmutex.c
blob: 0e3c37f072e8017a646c522f9a943f5d4177b59d (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
/* 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/. */

#include "seccomon.h"
/* This ifdef should match the one in sslsnce.c */
#if defined(XP_UNIX) || defined(XP_WIN32) || defined(XP_OS2)

#include "sslmutex.h"
#include "prerr.h"

static SECStatus
single_process_sslMutex_Init(sslMutex* pMutex)
{
    PR_ASSERT(pMutex != 0 && pMutex->u.sslLock == 0);

    pMutex->u.sslLock = PR_NewLock();
    if (!pMutex->u.sslLock) {
        return SECFailure;
    }
    return SECSuccess;
}

static SECStatus
single_process_sslMutex_Destroy(sslMutex* pMutex)
{
    PR_ASSERT(pMutex != 0);
    PR_ASSERT(pMutex->u.sslLock != 0);
    if (!pMutex->u.sslLock) {
        PORT_SetError(PR_INVALID_ARGUMENT_ERROR);
        return SECFailure;
    }
    PR_DestroyLock(pMutex->u.sslLock);
    return SECSuccess;
}

static SECStatus
single_process_sslMutex_Unlock(sslMutex* pMutex)
{
    PR_ASSERT(pMutex != 0);
    PR_ASSERT(pMutex->u.sslLock != 0);
    if (!pMutex->u.sslLock) {
        PORT_SetError(PR_INVALID_ARGUMENT_ERROR);
        return SECFailure;
    }
    PR_Unlock(pMutex->u.sslLock);
    return SECSuccess;
}

static SECStatus
single_process_sslMutex_Lock(sslMutex* pMutex)
{
    PR_ASSERT(pMutex != 0);
    PR_ASSERT(pMutex->u.sslLock != 0);
    if (!pMutex->u.sslLock) {
        PORT_SetError(PR_INVALID_ARGUMENT_ERROR);
        return SECFailure;
    }
    PR_Lock(pMutex->u.sslLock);
    return SECSuccess;
}

#if defined(LINUX) || defined(AIX) || defined(BSDI) || \
    (defined(NETBSD) && __NetBSD_Version__ < 500000000) || defined(OPENBSD) || defined(__GLIBC__)

#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>
#include "unix_err.h"
#include "pratom.h"

#define SSL_MUTEX_MAGIC 0xfeedfd
#define NONBLOCKING_POSTS 1 /* maybe this is faster */

#if NONBLOCKING_POSTS

#ifndef FNONBLOCK
#define FNONBLOCK O_NONBLOCK
#endif

static int
setNonBlocking(int fd, int nonBlocking)
{
    int flags;
    int err;

    flags = fcntl(fd, F_GETFL, 0);
    if (0 > flags)
        return flags;
    if (nonBlocking)
        flags |= FNONBLOCK;
    else
        flags &= ~FNONBLOCK;
    err = fcntl(fd, F_SETFL, flags);
    return err;
}
#endif

SECStatus
sslMutex_Init(sslMutex* pMutex, int shared)
{
    int err;
    PR_ASSERT(pMutex);
    pMutex->isMultiProcess = (PRBool)(shared != 0);
    if (!shared) {
        return single_process_sslMutex_Init(pMutex);
    }
    pMutex->u.pipeStr.mPipes[0] = -1;
    pMutex->u.pipeStr.mPipes[1] = -1;
    pMutex->u.pipeStr.mPipes[2] = -1;
    pMutex->u.pipeStr.nWaiters = 0;

    err = pipe(pMutex->u.pipeStr.mPipes);
    if (err) {
        nss_MD_unix_map_default_error(errno);
        return err;
    }
#if NONBLOCKING_POSTS
    err = setNonBlocking(pMutex->u.pipeStr.mPipes[1], 1);
    if (err)
        goto loser;
#endif

    pMutex->u.pipeStr.mPipes[2] = SSL_MUTEX_MAGIC;

#if defined(LINUX) && defined(i386)
    /* Pipe starts out empty */
    return SECSuccess;
#else
    /* Pipe starts with one byte. */
    return sslMutex_Unlock(pMutex);
#endif

loser:
    nss_MD_unix_map_default_error(errno);
    close(pMutex->u.pipeStr.mPipes[0]);
    close(pMutex->u.pipeStr.mPipes[1]);
    return SECFailure;
}

SECStatus
sslMutex_Destroy(sslMutex* pMutex, PRBool processLocal)
{
    if (PR_FALSE == pMutex->isMultiProcess) {
        return single_process_sslMutex_Destroy(pMutex);
    }
    if (pMutex->u.pipeStr.mPipes[2] != SSL_MUTEX_MAGIC) {
        PORT_SetError(PR_INVALID_ARGUMENT_ERROR);
        return SECFailure;
    }
    close(pMutex->u.pipeStr.mPipes[0]);
    close(pMutex->u.pipeStr.mPipes[1]);

    if (processLocal) {
        return SECSuccess;
    }

    pMutex->u.pipeStr.mPipes[0] = -1;
    pMutex->u.pipeStr.mPipes[1] = -1;
    pMutex->u.pipeStr.mPipes[2] = -1;
    pMutex->u.pipeStr.nWaiters = 0;

    return SECSuccess;
}

#if defined(LINUX) && defined(i386)
/* No memory barrier needed for this platform */

/* nWaiters includes the holder of the lock (if any) and the number
** threads waiting for it.  After incrementing nWaiters, if the count
** is exactly 1, then you have the lock and may proceed.  If the
** count is greater than 1, then you must wait on the pipe.
*/

SECStatus
sslMutex_Unlock(sslMutex* pMutex)
{
    PRInt32 newValue;
    if (PR_FALSE == pMutex->isMultiProcess) {
        return single_process_sslMutex_Unlock(pMutex);
    }

    if (pMutex->u.pipeStr.mPipes[2] != SSL_MUTEX_MAGIC) {
        PORT_SetError(PR_INVALID_ARGUMENT_ERROR);
        return SECFailure;
    }
    /* Do Memory Barrier here. */
    newValue = PR_ATOMIC_DECREMENT(&pMutex->u.pipeStr.nWaiters);
    if (newValue > 0) {
        int cc;
        char c = 1;
        do {
            cc = write(pMutex->u.pipeStr.mPipes[1], &c, 1);
        } while (cc < 0 && (errno == EINTR || errno == EAGAIN));
        if (cc != 1) {
            if (cc < 0)
                nss_MD_unix_map_default_error(errno);
            else
                PORT_SetError(PR_UNKNOWN_ERROR);
            return SECFailure;
        }
    }
    return SECSuccess;
}

SECStatus
sslMutex_Lock(sslMutex* pMutex)
{
    PRInt32 newValue;
    if (PR_FALSE == pMutex->isMultiProcess) {
        return single_process_sslMutex_Lock(pMutex);
    }

    if (pMutex->u.pipeStr.mPipes[2] != SSL_MUTEX_MAGIC) {
        PORT_SetError(PR_INVALID_ARGUMENT_ERROR);
        return SECFailure;
    }
    newValue = PR_ATOMIC_INCREMENT(&pMutex->u.pipeStr.nWaiters);
    /* Do Memory Barrier here. */
    if (newValue > 1) {
        int cc;
        char c;
        do {
            cc = read(pMutex->u.pipeStr.mPipes[0], &c, 1);
        } while (cc < 0 && errno == EINTR);
        if (cc != 1) {
            if (cc < 0)
                nss_MD_unix_map_default_error(errno);
            else
                PORT_SetError(PR_UNKNOWN_ERROR);
            return SECFailure;
        }
    }
    return SECSuccess;
}

#else

/* Using Atomic operations requires the use of a memory barrier instruction
** on PowerPC, Sparc, and Alpha.  NSPR's PR_Atomic functions do not perform
** them, and NSPR does not provide a function that does them (e.g. PR_Barrier).
** So, we don't use them on those platforms.
*/

SECStatus
sslMutex_Unlock(sslMutex* pMutex)
{
    int cc;
    char c = 1;

    if (PR_FALSE == pMutex->isMultiProcess) {
        return single_process_sslMutex_Unlock(pMutex);
    }

    if (pMutex->u.pipeStr.mPipes[2] != SSL_MUTEX_MAGIC) {
        PORT_SetError(PR_INVALID_ARGUMENT_ERROR);
        return SECFailure;
    }
    do {
        cc = write(pMutex->u.pipeStr.mPipes[1], &c, 1);
    } while (cc < 0 && (errno == EINTR || errno == EAGAIN));
    if (cc != 1) {
        if (cc < 0)
            nss_MD_unix_map_default_error(errno);
        else
            PORT_SetError(PR_UNKNOWN_ERROR);
        return SECFailure;
    }

    return SECSuccess;
}

SECStatus
sslMutex_Lock(sslMutex* pMutex)
{
    int cc;
    char c;

    if (PR_FALSE == pMutex->isMultiProcess) {
        return single_process_sslMutex_Lock(pMutex);
    }

    if (pMutex->u.pipeStr.mPipes[2] != SSL_MUTEX_MAGIC) {
        PORT_SetError(PR_INVALID_ARGUMENT_ERROR);
        return SECFailure;
    }

    do {
        cc = read(pMutex->u.pipeStr.mPipes[0], &c, 1);
    } while (cc < 0 && errno == EINTR);
    if (cc != 1) {
        if (cc < 0)
            nss_MD_unix_map_default_error(errno);
        else
            PORT_SetError(PR_UNKNOWN_ERROR);
        return SECFailure;
    }

    return SECSuccess;
}

#endif

#elif defined(WIN32)

#include "win32err.h"

/* on Windows, we need to find the optimal type of locking mechanism to use
 for the sslMutex.

 There are 3 cases :
 1) single-process, use a PRLock, as for all other platforms
 2) Win95 multi-process, use a Win32 mutex
 3) on WINNT multi-process, use a PRLock + a Win32 mutex

*/

#ifdef WINNT

SECStatus
sslMutex_2LevelInit(sslMutex *sem)
{
    /*  the following adds a PRLock to sslMutex . This is done in each
        process of a multi-process server and is only needed on WINNT, if
        using fibers. We can't tell if native threads or fibers are used, so
        we always do it on WINNT
    */
    PR_ASSERT(sem);
    if (sem) {
        /* we need to reset the sslLock in the children or the single_process init
           function below will assert */
        sem->u.sslLock = NULL;
    }
    return single_process_sslMutex_Init(sem);
}

static SECStatus
sslMutex_2LevelDestroy(sslMutex *sem)
{
    return single_process_sslMutex_Destroy(sem);
}

#endif

SECStatus
sslMutex_Init(sslMutex *pMutex, int shared)
{
#ifdef WINNT
    SECStatus retvalue;
#endif
    HANDLE hMutex;
    SECURITY_ATTRIBUTES attributes = { sizeof(SECURITY_ATTRIBUTES), NULL, TRUE };

    PR_ASSERT(pMutex != 0 && (pMutex->u.sslMutx == 0 ||
                              pMutex->u.sslMutx ==
                                  INVALID_HANDLE_VALUE));

    pMutex->isMultiProcess = (PRBool)(shared != 0);

    if (PR_FALSE == pMutex->isMultiProcess) {
        return single_process_sslMutex_Init(pMutex);
    }

#ifdef WINNT
    /*  we need a lock on WINNT for fibers in the parent process */
    retvalue = sslMutex_2LevelInit(pMutex);
    if (SECSuccess != retvalue)
        return SECFailure;
#endif

    if (!pMutex || ((hMutex = pMutex->u.sslMutx) != 0 &&
                    hMutex !=
                        INVALID_HANDLE_VALUE)) {
        PORT_SetError(PR_INVALID_ARGUMENT_ERROR);
        return SECFailure;
    }
    attributes.bInheritHandle = (shared ? TRUE : FALSE);
    hMutex = CreateMutex(&attributes, FALSE, NULL);
    if (hMutex == NULL) {
        hMutex = INVALID_HANDLE_VALUE;
        nss_MD_win32_map_default_error(GetLastError());
        return SECFailure;
    }
    pMutex->u.sslMutx = hMutex;
    return SECSuccess;
}

SECStatus
sslMutex_Destroy(sslMutex *pMutex, PRBool processLocal)
{
    HANDLE hMutex;
    int rv;
    int retvalue = SECSuccess;

    PR_ASSERT(pMutex != 0);
    if (!pMutex) {
        PORT_SetError(PR_INVALID_ARGUMENT_ERROR);
        return SECFailure;
    }

    if (PR_FALSE == pMutex->isMultiProcess) {
        return single_process_sslMutex_Destroy(pMutex);
    }

/*  multi-process mode */
#ifdef WINNT
    /* on NT, get rid of the PRLock used for fibers within a process */
    retvalue = sslMutex_2LevelDestroy(pMutex);
#endif

    PR_ASSERT(pMutex->u.sslMutx != 0 &&
              pMutex->u.sslMutx != INVALID_HANDLE_VALUE);
    if ((hMutex = pMutex->u.sslMutx) == 0 || hMutex == INVALID_HANDLE_VALUE) {
        PORT_SetError(PR_INVALID_ARGUMENT_ERROR);
        return SECFailure;
    }

    rv = CloseHandle(hMutex); /* ignore error */
    if (!processLocal && rv) {
        pMutex->u.sslMutx = hMutex = INVALID_HANDLE_VALUE;
    }
    if (!rv) {
        nss_MD_win32_map_default_error(GetLastError());
        retvalue = SECFailure;
    }
    return retvalue;
}

int
sslMutex_Unlock(sslMutex *pMutex)
{
    BOOL success = FALSE;
    HANDLE hMutex;

    PR_ASSERT(pMutex != 0);
    if (!pMutex) {
        PORT_SetError(PR_INVALID_ARGUMENT_ERROR);
        return SECFailure;
    }

    if (PR_FALSE == pMutex->isMultiProcess) {
        return single_process_sslMutex_Unlock(pMutex);
    }

    PR_ASSERT(pMutex->u.sslMutx != 0 &&
              pMutex->u.sslMutx != INVALID_HANDLE_VALUE);
    if ((hMutex = pMutex->u.sslMutx) == 0 || hMutex == INVALID_HANDLE_VALUE) {
        PORT_SetError(PR_INVALID_ARGUMENT_ERROR);
        return SECFailure;
    }
    success = ReleaseMutex(hMutex);
    if (!success) {
        nss_MD_win32_map_default_error(GetLastError());
        return SECFailure;
    }
#ifdef WINNT
    return single_process_sslMutex_Unlock(pMutex);
/* release PRLock for other fibers in the process */
#else
    return SECSuccess;
#endif
}

int
sslMutex_Lock(sslMutex *pMutex)
{
    HANDLE hMutex;
    DWORD event;
    DWORD lastError;
    SECStatus rv;
    SECStatus retvalue = SECSuccess;

    PR_ASSERT(pMutex != 0);
    if (!pMutex) {
        PORT_SetError(PR_INVALID_ARGUMENT_ERROR);
        return SECFailure;
    }

    if (PR_FALSE == pMutex->isMultiProcess) {
        return single_process_sslMutex_Lock(pMutex);
    }
#ifdef WINNT
    /* lock first to preserve from other threads/fibers in the same process */
    retvalue = single_process_sslMutex_Lock(pMutex);
#endif
    PR_ASSERT(pMutex->u.sslMutx != 0 &&
              pMutex->u.sslMutx != INVALID_HANDLE_VALUE);
    if ((hMutex = pMutex->u.sslMutx) == 0 || hMutex == INVALID_HANDLE_VALUE) {
        PORT_SetError(PR_INVALID_ARGUMENT_ERROR);
        return SECFailure; /* what else ? */
    }
    /* acquire the mutex to be the only owner accross all other processes */
    event = WaitForSingleObject(hMutex, INFINITE);
    switch (event) {
        case WAIT_OBJECT_0:
        case WAIT_ABANDONED:
            rv = SECSuccess;
            break;

        case WAIT_TIMEOUT:
#if defined(WAIT_IO_COMPLETION)
        case WAIT_IO_COMPLETION:
#endif
        default: /* should never happen. nothing we can do. */
            PR_ASSERT(PR_FALSE && "WaitForSingleObject returned invalid value.");
            PORT_SetError(PR_UNKNOWN_ERROR);
            rv = SECFailure;
            break;

        case WAIT_FAILED: /* failure returns this */
            rv = SECFailure;
            lastError = GetLastError(); /* for debugging */
            nss_MD_win32_map_default_error(lastError);
            break;
    }

    if (!(SECSuccess == retvalue && SECSuccess == rv)) {
        return SECFailure;
    }

    return SECSuccess;
}

#elif defined(XP_UNIX) && !defined(DARWIN)

#include <errno.h>
#include "unix_err.h"

SECStatus
sslMutex_Init(sslMutex* pMutex, int shared)
{
    int rv;
    PR_ASSERT(pMutex);
    pMutex->isMultiProcess = (PRBool)(shared != 0);
    if (!shared) {
        return single_process_sslMutex_Init(pMutex);
    }
    do {
        rv = sem_init(&pMutex->u.sem, shared, 1);
    } while (rv < 0 && errno == EINTR);
    if (rv < 0) {
        nss_MD_unix_map_default_error(errno);
        return SECFailure;
    }
    return SECSuccess;
}

SECStatus
sslMutex_Destroy(sslMutex* pMutex, PRBool processLocal)
{
    int rv;
    if (PR_FALSE == pMutex->isMultiProcess) {
        return single_process_sslMutex_Destroy(pMutex);
    }

    /* semaphores are global resources. See SEM_DESTROY(3) man page */
    if (processLocal) {
        return SECSuccess;
    }
    do {
        rv = sem_destroy(&pMutex->u.sem);
    } while (rv < 0 && errno == EINTR);
    if (rv < 0) {
        nss_MD_unix_map_default_error(errno);
        return SECFailure;
    }
    return SECSuccess;
}

SECStatus
sslMutex_Unlock(sslMutex* pMutex)
{
    int rv;
    if (PR_FALSE == pMutex->isMultiProcess) {
        return single_process_sslMutex_Unlock(pMutex);
    }
    do {
        rv = sem_post(&pMutex->u.sem);
    } while (rv < 0 && errno == EINTR);
    if (rv < 0) {
        nss_MD_unix_map_default_error(errno);
        return SECFailure;
    }
    return SECSuccess;
}

SECStatus
sslMutex_Lock(sslMutex* pMutex)
{
    int rv;
    if (PR_FALSE == pMutex->isMultiProcess) {
        return single_process_sslMutex_Lock(pMutex);
    }
    do {
        rv = sem_wait(&pMutex->u.sem);
    } while (rv < 0 && errno == EINTR);
    if (rv < 0) {
        nss_MD_unix_map_default_error(errno);
        return SECFailure;
    }
    return SECSuccess;
}

#else

SECStatus
sslMutex_Init(sslMutex* pMutex, int shared)
{
    PR_ASSERT(pMutex);
    pMutex->isMultiProcess = (PRBool)(shared != 0);
    if (!shared) {
        return single_process_sslMutex_Init(pMutex);
    }
    PORT_Assert(PR_FALSE && "sslMutex_Init not implemented for multi-process applications !");
    PORT_SetError(PR_NOT_IMPLEMENTED_ERROR);
    return SECFailure;
}

SECStatus
sslMutex_Destroy(sslMutex* pMutex, PRBool processLocal)
{
    PR_ASSERT(pMutex);
    if (PR_FALSE == pMutex->isMultiProcess) {
        return single_process_sslMutex_Destroy(pMutex);
    }
    PORT_Assert(PR_FALSE && "sslMutex_Destroy not implemented for multi-process applications !");
    PORT_SetError(PR_NOT_IMPLEMENTED_ERROR);
    return SECFailure;
}

SECStatus
sslMutex_Unlock(sslMutex* pMutex)
{
    PR_ASSERT(pMutex);
    if (PR_FALSE == pMutex->isMultiProcess) {
        return single_process_sslMutex_Unlock(pMutex);
    }
    PORT_Assert(PR_FALSE && "sslMutex_Unlock not implemented for multi-process applications !");
    PORT_SetError(PR_NOT_IMPLEMENTED_ERROR);
    return SECFailure;
}

SECStatus
sslMutex_Lock(sslMutex* pMutex)
{
    PR_ASSERT(pMutex);
    if (PR_FALSE == pMutex->isMultiProcess) {
        return single_process_sslMutex_Lock(pMutex);
    }
    PORT_Assert(PR_FALSE && "sslMutex_Lock not implemented for multi-process applications !");
    PORT_SetError(PR_NOT_IMPLEMENTED_ERROR);
    return SECFailure;
}

#endif

#endif