aboutsummaryrefslogtreecommitdiffstats
path: root/crypto/bio/bss_acpt.c
blob: 5a2cb50dfc39fe2e561602d8087a26b92e47606a (plain) (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
/*
 * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the OpenSSL license (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */

#include <stdio.h>
#include <errno.h>
#include "bio_local.h"

#ifndef OPENSSL_NO_SOCK

typedef struct bio_accept_st {
    int state;
    int accept_family;
    int bind_mode;     /* Socket mode for BIO_listen */
    int accepted_mode; /* Socket mode for BIO_accept (set on accepted sock) */
    char *param_addr;
    char *param_serv;

    int accept_sock;

    BIO_ADDRINFO *addr_first;
    const BIO_ADDRINFO *addr_iter;
    BIO_ADDR cache_accepting_addr;   /* Useful if we asked for port 0 */
    char *cache_accepting_name, *cache_accepting_serv;
    BIO_ADDR cache_peer_addr;
    char *cache_peer_name, *cache_peer_serv;

    BIO *bio_chain;
} BIO_ACCEPT;

static int acpt_write(BIO *h, const char *buf, int num);
static int acpt_read(BIO *h, char *buf, int size);
static int acpt_puts(BIO *h, const char *str);
static long acpt_ctrl(BIO *h, int cmd, long arg1, void *arg2);
static int acpt_new(BIO *h);
static int acpt_free(BIO *data);
static int acpt_state(BIO *b, BIO_ACCEPT *c);
static void acpt_close_socket(BIO *data);
static BIO_ACCEPT *BIO_ACCEPT_new(void);
static void BIO_ACCEPT_free(BIO_ACCEPT *a);

# define ACPT_S_BEFORE                   1
# define ACPT_S_GET_ADDR                 2
# define ACPT_S_CREATE_SOCKET            3
# define ACPT_S_LISTEN                   4
# define ACPT_S_ACCEPT                   5
# define ACPT_S_OK                       6

static const BIO_METHOD methods_acceptp = {
    BIO_TYPE_ACCEPT,
    "socket accept",
    /* TODO: Convert to new style write function */
    bwrite_conv,
    acpt_write,
    /* TODO: Convert to new style read function */
    bread_conv,
    acpt_read,
    acpt_puts,
    NULL,                       /* connect_gets,         */
    acpt_ctrl,
    acpt_new,
    acpt_free,
    NULL,                       /* connect_callback_ctrl */
};

const BIO_METHOD *BIO_s_accept(void)
{
    return &methods_acceptp;
}

static int acpt_new(BIO *bi)
{
    BIO_ACCEPT *ba;

    bi->init = 0;
    bi->num = (int)INVALID_SOCKET;
    bi->flags = 0;
    if ((ba = BIO_ACCEPT_new()) == NULL)
        return 0;
    bi->ptr = (char *)ba;
    ba->state = ACPT_S_BEFORE;
    bi->shutdown = 1;
    return 1;
}

static BIO_ACCEPT *BIO_ACCEPT_new(void)
{
    BIO_ACCEPT *ret;

    if ((ret = OPENSSL_zalloc(sizeof(*ret))) == NULL) {
        BIOerr(BIO_F_BIO_ACCEPT_NEW, ERR_R_MALLOC_FAILURE);
        return NULL;
    }
    ret->accept_family = BIO_FAMILY_IPANY;
    ret->accept_sock = (int)INVALID_SOCKET;
    return ret;
}

static void BIO_ACCEPT_free(BIO_ACCEPT *a)
{
    if (a == NULL)
        return;
    OPENSSL_free(a->param_addr);
    OPENSSL_free(a->param_serv);
    BIO_ADDRINFO_free(a->addr_first);
    OPENSSL_free(a->cache_accepting_name);
    OPENSSL_free(a->cache_accepting_serv);
    OPENSSL_free(a->cache_peer_name);
    OPENSSL_free(a->cache_peer_serv);
    BIO_free(a->bio_chain);
    OPENSSL_free(a);
}

static void acpt_close_socket(BIO *bio)
{
    BIO_ACCEPT *c;

    c = (BIO_ACCEPT *)bio->ptr;
    if (c->accept_sock != (int)INVALID_SOCKET) {
        shutdown(c->accept_sock, 2);
        closesocket(c->accept_sock);
        c->accept_sock = (int)INVALID_SOCKET;
        bio->num = (int)INVALID_SOCKET;
    }
}

static int acpt_free(BIO *a)
{
    BIO_ACCEPT *data;

    if (a == NULL)
        return 0;
    data = (BIO_ACCEPT *)a->ptr;

    if (a->shutdown) {
        acpt_close_socket(a);
        BIO_ACCEPT_free(data);
        a->ptr = NULL;
        a->flags = 0;
        a->init = 0;
    }
    return 1;
}

static int acpt_state(BIO *b, BIO_ACCEPT *c)
{
    BIO *bio = NULL, *dbio;
    int s = -1, ret = -1;

    for (;;) {
        switch (c->state) {
        case ACPT_S_BEFORE:
            if (c->param_addr == NULL && c->param_serv == NULL) {
                BIOerr(BIO_F_ACPT_STATE, BIO_R_NO_ACCEPT_ADDR_OR_SERVICE_SPECIFIED);
                ERR_add_error_data(4,
                                   "hostname=", c->param_addr,
                                   " service=", c->param_serv);
                goto exit_loop;
            }

            /* Because we're starting a new bind, any cached name and serv
             * are now obsolete and need to be cleaned out.
             * QUESTION: should this be done in acpt_close_socket() instead?
             */
            OPENSSL_free(c->cache_accepting_name);
            c->cache_accepting_name = NULL;
            OPENSSL_free(c->cache_accepting_serv);
            c->cache_accepting_serv = NULL;
            OPENSSL_free(c->cache_peer_name);
            c->cache_peer_name = NULL;
            OPENSSL_free(c->cache_peer_serv);
            c->cache_peer_serv = NULL;

            c->state = ACPT_S_GET_ADDR;
            break;

        case ACPT_S_GET_ADDR:
            {
                int family = AF_UNSPEC;
                switch (c->accept_family) {
                case BIO_FAMILY_IPV6:
                    if (1) { /* This is a trick we use to avoid bit rot.
                              * at least the "else" part will always be
                              * compiled.
                              */
#ifdef AF_INET6
                        family = AF_INET6;
                    } else {
#endif
                        BIOerr(BIO_F_ACPT_STATE, BIO_R_UNAVAILABLE_IP_FAMILY);
                        goto exit_loop;
                    }
                    break;
                case BIO_FAMILY_IPV4:
                    family = AF_INET;
                    break;
                case BIO_FAMILY_IPANY:
                    family = AF_UNSPEC;
                    break;
                default:
                    BIOerr(BIO_F_ACPT_STATE, BIO_R_UNSUPPORTED_IP_FAMILY);
                    goto exit_loop;
                }
                if (BIO_lookup(c->param_addr, c->param_serv, BIO_LOOKUP_SERVER,
                               family, SOCK_STREAM, &c->addr_first) == 0)
                    goto exit_loop;
            }
            if (c->addr_first == NULL) {
                BIOerr(BIO_F_ACPT_STATE, BIO_R_LOOKUP_RETURNED_NOTHING);
                goto exit_loop;
            }
            /* We're currently not iterating, but set this as preparation
             * for possible future development in that regard
             */
            c->addr_iter = c->addr_first;
            c->state = ACPT_S_CREATE_SOCKET;
            break;

        case ACPT_S_CREATE_SOCKET:
            s = BIO_socket(BIO_ADDRINFO_family(c->addr_iter),
                           BIO_ADDRINFO_socktype(c->addr_iter),
                           BIO_ADDRINFO_protocol(c->addr_iter), 0);
            if (s == (int)INVALID_SOCKET) {
                SYSerr(SYS_F_SOCKET, get_last_socket_error());
                ERR_add_error_data(4,
                                   "hostname=", c->param_addr,
                                   " service=", c->param_serv);
                BIOerr(BIO_F_ACPT_STATE, BIO_R_UNABLE_TO_CREATE_SOCKET);
                goto exit_loop;
            }
            c->accept_sock = s;
            b->num = s;
            c->state = ACPT_S_LISTEN;
            s = -1;
            break;

        case ACPT_S_LISTEN:
            {
                if (!BIO_listen(c->accept_sock,
                                BIO_ADDRINFO_address(c->addr_iter),
                                c->bind_mode)) {
                    BIO_closesocket(c->accept_sock);
                    goto exit_loop;
                }
            }

            {
                union BIO_sock_info_u info;

                info.addr = &c->cache_accepting_addr;
                if (!BIO_sock_info(c->accept_sock, BIO_SOCK_INFO_ADDRESS,
                                   &info)) {
                    BIO_closesocket(c->accept_sock);
                    goto exit_loop;
                }
            }

            c->cache_accepting_name =
                BIO_ADDR_hostname_string(&c->cache_accepting_addr, 1);
            c->cache_accepting_serv =
                BIO_ADDR_service_string(&c->cache_accepting_addr, 1);
            c->state = ACPT_S_ACCEPT;
            s = -1;
            ret = 1;
            goto end;

        case ACPT_S_ACCEPT:
            if (b->next_bio != NULL) {
                c->state = ACPT_S_OK;
                break;
            }
            BIO_clear_retry_flags(b);
            b->retry_reason = 0;

            OPENSSL_free(c->cache_peer_name);
            c->cache_peer_name = NULL;
            OPENSSL_free(c->cache_peer_serv);
            c->cache_peer_serv = NULL;

            s = BIO_accept_ex(c->accept_sock, &c->cache_peer_addr,
                              c->accepted_mode);

            /* If the returned socket is invalid, this might still be
             * retryable
             */
            if (s < 0) {
                if (BIO_sock_should_retry(s)) {
                    BIO_set_retry_special(b);
                    b->retry_reason = BIO_RR_ACCEPT;
                    goto end;
                }
            }

            /* If it wasn't retryable, we fail */
            if (s < 0) {
                ret = s;
                goto exit_loop;
            }

            bio = BIO_new_socket(s, BIO_CLOSE);
            if (bio == NULL)
                goto exit_loop;

            BIO_set_callback(bio, BIO_get_callback(b));
            BIO_set_callback_arg(bio, BIO_get_callback_arg(b));

            /*
             * If the accept BIO has an bio_chain, we dup it and put the new
             * socket at the end.
             */
            if (c->bio_chain != NULL) {
                if ((dbio = BIO_dup_chain(c->bio_chain)) == NULL)
                    goto exit_loop;
                if (!BIO_push(dbio, bio))
                    goto exit_loop;
                bio = dbio;
            }
            if (BIO_push(b, bio) == NULL)
                goto exit_loop;

            c->cache_peer_name =
                BIO_ADDR_hostname_string(&c->cache_peer_addr, 1);
            c->cache_peer_serv =
                BIO_ADDR_service_string(&c->cache_peer_addr, 1);
            c->state = ACPT_S_OK;
            bio = NULL;
            ret = 1;
            goto end;

        case ACPT_S_OK:
            if (b->next_bio == NULL) {
                c->state = ACPT_S_ACCEPT;
                break;
            }
            ret = 1;
            goto end;

        default:
            ret = 0;
            goto end;
        }
    }

  exit_loop:
    if (bio != NULL)
        BIO_free(bio);
    else if (s >= 0)
        BIO_closesocket(s);
  end:
    return ret;
}

static int acpt_read(BIO *b, char *out, int outl)
{
    int ret = 0;
    BIO_ACCEPT *data;

    BIO_clear_retry_flags(b);
    data = (BIO_ACCEPT *)b->ptr;

    while (b->next_bio == NULL) {
        ret = acpt_state(b, data);
        if (ret <= 0)
            return ret;
    }

    ret = BIO_read(b->next_bio, out, outl);
    BIO_copy_next_retry(b);
    return ret;
}

static int acpt_write(BIO *b, const char *in, int inl)
{
    int ret;
    BIO_ACCEPT *data;

    BIO_clear_retry_flags(b);
    data = (BIO_ACCEPT *)b->ptr;

    while (b->next_bio == NULL) {
        ret = acpt_state(b, data);
        if (ret <= 0)
            return ret;
    }

    ret = BIO_write(b->next_bio, in, inl);
    BIO_copy_next_retry(b);
    return ret;
}

static long acpt_ctrl(BIO *b, int cmd, long num, void *ptr)
{
    int *ip;
    long ret = 1;
    BIO_ACCEPT *data;
    char **pp;

    data = (BIO_ACCEPT *)b->ptr;

    switch (cmd) {
    case BIO_CTRL_RESET:
        ret = 0;
        data->state = ACPT_S_BEFORE;
        acpt_close_socket(b);
        BIO_ADDRINFO_free(data->addr_first);
        data->addr_first = NULL;
        b->flags = 0;
        break;
    case BIO_C_DO_STATE_MACHINE:
        /* use this one to start the connection */
        ret = (long)acpt_state(b, data);
        break;
    case BIO_C_SET_ACCEPT:
        if (ptr != NULL) {
            if (num == 0) {
                char *hold_serv = data->param_serv;
                /* We affect the hostname regardless.  However, the input
                 * string might contain a host:service spec, so we must
                 * parse it, which might or might not affect the service
                 */
                OPENSSL_free(data->param_addr);
                data->param_addr = NULL;
                ret = BIO_parse_hostserv(ptr,
                                         &data->param_addr,
                                         &data->param_serv,
                                         BIO_PARSE_PRIO_SERV);
                if (hold_serv != data->param_serv)
                    OPENSSL_free(hold_serv);
                b->init = 1;
            } else if (num == 1) {
                OPENSSL_free(data->param_serv);
                data->param_serv = BUF_strdup(ptr);
                b->init = 1;
            } else if (num == 2) {
                data->bind_mode |= BIO_SOCK_NONBLOCK;
            } else if (num == 3) {
                BIO_free(data->bio_chain);
                data->bio_chain = (BIO *)ptr;
            } else if (num == 4) {
                data->accept_family = *(int *)ptr;
            }
        } else {
            if (num == 2) {
                data->bind_mode &= ~BIO_SOCK_NONBLOCK;
            }
        }
        break;
    case BIO_C_SET_NBIO:
        if (num != 0)
            data->accepted_mode |= BIO_SOCK_NONBLOCK;
        else
            data->accepted_mode &= ~BIO_SOCK_NONBLOCK;
        break;
    case BIO_C_SET_FD:
        b->num = *((int *)ptr);
        data->accept_sock = b->num;
        data->state = ACPT_S_ACCEPT;
        b->shutdown = (int)num;
        b->init = 1;
        break;
    case BIO_C_GET_FD:
        if (b->init) {
            ip = (int *)ptr;
            if (ip != NULL)
                *ip = data->accept_sock;
            ret = data->accept_sock;
        } else
            ret = -1;
        break;
    case BIO_C_GET_ACCEPT:
        if (b->init) {
            if (num == 0 && ptr != NULL) {
                pp = (char **)ptr;
                *pp = data->cache_accepting_name;
            } else if (num == 1 && ptr != NULL) {
                pp = (char **)ptr;
                *pp = data->cache_accepting_serv;
            } else if (num == 2 && ptr != NULL) {
                pp = (char **)ptr;
                *pp = data->cache_peer_name;
            } else if (num == 3 && ptr != NULL) {
                pp = (char **)ptr;
                *pp = data->cache_peer_serv;
            } else if (num == 4) {
                switch (BIO_ADDRINFO_family(data->addr_iter)) {
#ifdef AF_INET6
                case AF_INET6:
                    ret = BIO_FAMILY_IPV6;
                    break;
#endif
                case AF_INET:
                    ret = BIO_FAMILY_IPV4;
                    break;
                case 0:
                    ret = data->accept_family;
                    break;
                default:
                    ret = -1;
                    break;
                }
            } else
                ret = -1;
        } else
            ret = -1;
        break;
    case BIO_CTRL_GET_CLOSE:
        ret = b->shutdown;
        break;
    case BIO_CTRL_SET_CLOSE:
        b->shutdown = (int)num;
        break;
    case BIO_CTRL_PENDING:
    case BIO_CTRL_WPENDING:
        ret = 0;
        break;
    case BIO_CTRL_FLUSH:
        break;
    case BIO_C_SET_BIND_MODE:
        data->bind_mode = (int)num;
        break;
    case BIO_C_GET_BIND_MODE:
        ret = (long)data->bind_mode;
        break;
    case BIO_CTRL_DUP:
        break;
    case BIO_CTRL_EOF:
        if (b->next_bio == NULL)
            ret = 0;
        else
            ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
        break;
    default:
        ret = 0;
        break;
    }
    return ret;
}

static int acpt_puts(BIO *bp, const char *str)
{
    int n, ret;

    n = strlen(str);
    ret = acpt_write(bp, str, n);
    return ret;
}

BIO *BIO_new_accept(const char *str)
{
    BIO *ret;

    ret = BIO_new(BIO_s_accept());
    if (ret == NULL)
        return NULL;
    if (BIO_set_accept_name(ret, str))
        return ret;
    BIO_free(ret);
    return NULL;
}

#endif