bss_bio.c revision 296465 
1/* crypto/bio/bss_bio.c  -*- Mode: C; c-file-style: "eay" -*- */
2/* ====================================================================
3 * Copyright (c) 1998-2003 The OpenSSL Project.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in
14 *    the documentation and/or other materials provided with the
15 *    distribution.
16 *
17 * 3. All advertising materials mentioning features or use of this
18 *    software must display the following acknowledgment:
19 *    "This product includes software developed by the OpenSSL Project
20 *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
21 *
22 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
23 *    endorse or promote products derived from this software without
24 *    prior written permission. For written permission, please contact
25 *    openssl-core@openssl.org.
26 *
27 * 5. Products derived from this software may not be called "OpenSSL"
28 *    nor may "OpenSSL" appear in their names without prior written
29 *    permission of the OpenSSL Project.
30 *
31 * 6. Redistributions of any form whatsoever must retain the following
32 *    acknowledgment:
33 *    "This product includes software developed by the OpenSSL Project
34 *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
35 *
36 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
37 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
39 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
40 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
41 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
42 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
43 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
44 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
45 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
46 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
47 * OF THE POSSIBILITY OF SUCH DAMAGE.
48 * ====================================================================
49 *
50 * This product includes cryptographic software written by Eric Young
51 * (eay@cryptsoft.com).  This product includes software written by Tim
52 * Hudson (tjh@cryptsoft.com).
53 *
54 */
55
56/*
57 * Special method for a BIO where the other endpoint is also a BIO of this
58 * kind, handled by the same thread (i.e. the "peer" is actually ourselves,
59 * wearing a different hat). Such "BIO pairs" are mainly for using the SSL
60 * library with I/O interfaces for which no specific BIO method is available.
61 * See ssl/ssltest.c for some hints on how this can be used.
62 */
63
64/* BIO_DEBUG implies BIO_PAIR_DEBUG */
65#ifdef BIO_DEBUG
66# ifndef BIO_PAIR_DEBUG
67#  define BIO_PAIR_DEBUG
68# endif
69#endif
70
71/* disable assert() unless BIO_PAIR_DEBUG has been defined */
72#ifndef BIO_PAIR_DEBUG
73# ifndef NDEBUG
74#  define NDEBUG
75# endif
76#endif
77
78#include <assert.h>
79#include <limits.h>
80#include <stdlib.h>
81#include <string.h>
82
83#include <openssl/bio.h>
84#include <openssl/err.h>
85#include <openssl/crypto.h>
86
87#include "e_os.h"
88
89/* VxWorks defines SSIZE_MAX with an empty value causing compile errors */
90#if defined(OPENSSL_SYS_VXWORKS)
91# undef SSIZE_MAX
92#endif
93#ifndef SSIZE_MAX
94# define SSIZE_MAX INT_MAX
95#endif
96
97static int bio_new(BIO *bio);
98static int bio_free(BIO *bio);
99static int bio_read(BIO *bio, char *buf, int size);
100static int bio_write(BIO *bio, const char *buf, int num);
101static long bio_ctrl(BIO *bio, int cmd, long num, void *ptr);
102static int bio_puts(BIO *bio, const char *str);
103
104static int bio_make_pair(BIO *bio1, BIO *bio2);
105static void bio_destroy_pair(BIO *bio);
106
107static BIO_METHOD methods_biop = {
108    BIO_TYPE_BIO,
109    "BIO pair",
110    bio_write,
111    bio_read,
112    bio_puts,
113    NULL /* no bio_gets */ ,
114    bio_ctrl,
115    bio_new,
116    bio_free,
117    NULL                        /* no bio_callback_ctrl */
118};
119
120BIO_METHOD *BIO_s_bio(void)
121{
122    return &methods_biop;
123}
124
125struct bio_bio_st {
126    BIO *peer;                  /* NULL if buf == NULL. If peer != NULL, then
127                                 * peer->ptr is also a bio_bio_st, and its
128                                 * "peer" member points back to us. peer !=
129                                 * NULL iff init != 0 in the BIO. */
130    /* This is for what we write (i.e. reading uses peer's struct): */
131    int closed;                 /* valid iff peer != NULL */
132    size_t len;                 /* valid iff buf != NULL; 0 if peer == NULL */
133    size_t offset;              /* valid iff buf != NULL; 0 if len == 0 */
134    size_t size;
135    char *buf;                  /* "size" elements (if != NULL) */
136    size_t request;             /* valid iff peer != NULL; 0 if len != 0,
137                                 * otherwise set by peer to number of bytes
138                                 * it (unsuccessfully) tried to read, never
139                                 * more than buffer space (size-len)
140                                 * warrants. */
141};
142
143static int bio_new(BIO *bio)
144{
145    struct bio_bio_st *b;
146
147    b = OPENSSL_malloc(sizeof *b);
148    if (b == NULL)
149        return 0;
150
151    b->peer = NULL;
152    /* enough for one TLS record (just a default) */
153    b->size = 17 * 1024;
154    b->buf = NULL;
155
156    bio->ptr = b;
157    return 1;
158}
159
160static int bio_free(BIO *bio)
161{
162    struct bio_bio_st *b;
163
164    if (bio == NULL)
165        return 0;
166    b = bio->ptr;
167
168    assert(b != NULL);
169
170    if (b->peer)
171        bio_destroy_pair(bio);
172
173    if (b->buf != NULL) {
174        OPENSSL_free(b->buf);
175    }
176
177    OPENSSL_free(b);
178
179    return 1;
180}
181
182static int bio_read(BIO *bio, char *buf, int size_)
183{
184    size_t size = size_;
185    size_t rest;
186    struct bio_bio_st *b, *peer_b;
187
188    BIO_clear_retry_flags(bio);
189
190    if (!bio->init)
191        return 0;
192
193    b = bio->ptr;
194    assert(b != NULL);
195    assert(b->peer != NULL);
196    peer_b = b->peer->ptr;
197    assert(peer_b != NULL);
198    assert(peer_b->buf != NULL);
199
200    peer_b->request = 0;        /* will be set in "retry_read" situation */
201
202    if (buf == NULL || size == 0)
203        return 0;
204
205    if (peer_b->len == 0) {
206        if (peer_b->closed)
207            return 0;           /* writer has closed, and no data is left */
208        else {
209            BIO_set_retry_read(bio); /* buffer is empty */
210            if (size <= peer_b->size)
211                peer_b->request = size;
212            else
213                /*
214                 * don't ask for more than the peer can deliver in one write
215                 */
216                peer_b->request = peer_b->size;
217            return -1;
218        }
219    }
220
221    /* we can read */
222    if (peer_b->len < size)
223        size = peer_b->len;
224
225    /* now read "size" bytes */
226
227    rest = size;
228
229    assert(rest > 0);
230    do {                        /* one or two iterations */
231        size_t chunk;
232
233        assert(rest <= peer_b->len);
234        if (peer_b->offset + rest <= peer_b->size)
235            chunk = rest;
236        else
237            /* wrap around ring buffer */
238            chunk = peer_b->size - peer_b->offset;
239        assert(peer_b->offset + chunk <= peer_b->size);
240
241        memcpy(buf, peer_b->buf + peer_b->offset, chunk);
242
243        peer_b->len -= chunk;
244        if (peer_b->len) {
245            peer_b->offset += chunk;
246            assert(peer_b->offset <= peer_b->size);
247            if (peer_b->offset == peer_b->size)
248                peer_b->offset = 0;
249            buf += chunk;
250        } else {
251            /* buffer now empty, no need to advance "buf" */
252            assert(chunk == rest);
253            peer_b->offset = 0;
254        }
255        rest -= chunk;
256    }
257    while (rest);
258
259    return size;
260}
261
262/*-
263 * non-copying interface: provide pointer to available data in buffer
264 *    bio_nread0:  return number of available bytes
265 *    bio_nread:   also advance index
266 * (example usage:  bio_nread0(), read from buffer, bio_nread()
267 *  or just         bio_nread(), read from buffer)
268 */
269/*
270 * WARNING: The non-copying interface is largely untested as of yet and may
271 * contain bugs.
272 */
273static ssize_t bio_nread0(BIO *bio, char **buf)
274{
275    struct bio_bio_st *b, *peer_b;
276    ssize_t num;
277
278    BIO_clear_retry_flags(bio);
279
280    if (!bio->init)
281        return 0;
282
283    b = bio->ptr;
284    assert(b != NULL);
285    assert(b->peer != NULL);
286    peer_b = b->peer->ptr;
287    assert(peer_b != NULL);
288    assert(peer_b->buf != NULL);
289
290    peer_b->request = 0;
291
292    if (peer_b->len == 0) {
293        char dummy;
294
295        /* avoid code duplication -- nothing available for reading */
296        return bio_read(bio, &dummy, 1); /* returns 0 or -1 */
297    }
298
299    num = peer_b->len;
300    if (peer_b->size < peer_b->offset + num)
301        /* no ring buffer wrap-around for non-copying interface */
302        num = peer_b->size - peer_b->offset;
303    assert(num > 0);
304
305    if (buf != NULL)
306        *buf = peer_b->buf + peer_b->offset;
307    return num;
308}
309
310static ssize_t bio_nread(BIO *bio, char **buf, size_t num_)
311{
312    struct bio_bio_st *b, *peer_b;
313    ssize_t num, available;
314
315    if (num_ > SSIZE_MAX)
316        num = SSIZE_MAX;
317    else
318        num = (ssize_t) num_;
319
320    available = bio_nread0(bio, buf);
321    if (num > available)
322        num = available;
323    if (num <= 0)
324        return num;
325
326    b = bio->ptr;
327    peer_b = b->peer->ptr;
328
329    peer_b->len -= num;
330    if (peer_b->len) {
331        peer_b->offset += num;
332        assert(peer_b->offset <= peer_b->size);
333        if (peer_b->offset == peer_b->size)
334            peer_b->offset = 0;
335    } else
336        peer_b->offset = 0;
337
338    return num;
339}
340
341static int bio_write(BIO *bio, const char *buf, int num_)
342{
343    size_t num = num_;
344    size_t rest;
345    struct bio_bio_st *b;
346
347    BIO_clear_retry_flags(bio);
348
349    if (!bio->init || buf == NULL || num == 0)
350        return 0;
351
352    b = bio->ptr;
353    assert(b != NULL);
354    assert(b->peer != NULL);
355    assert(b->buf != NULL);
356
357    b->request = 0;
358    if (b->closed) {
359        /* we already closed */
360        BIOerr(BIO_F_BIO_WRITE, BIO_R_BROKEN_PIPE);
361        return -1;
362    }
363
364    assert(b->len <= b->size);
365
366    if (b->len == b->size) {
367        BIO_set_retry_write(bio); /* buffer is full */
368        return -1;
369    }
370
371    /* we can write */
372    if (num > b->size - b->len)
373        num = b->size - b->len;
374
375    /* now write "num" bytes */
376
377    rest = num;
378
379    assert(rest > 0);
380    do {                        /* one or two iterations */
381        size_t write_offset;
382        size_t chunk;
383
384        assert(b->len + rest <= b->size);
385
386        write_offset = b->offset + b->len;
387        if (write_offset >= b->size)
388            write_offset -= b->size;
389        /* b->buf[write_offset] is the first byte we can write to. */
390
391        if (write_offset + rest <= b->size)
392            chunk = rest;
393        else
394            /* wrap around ring buffer */
395            chunk = b->size - write_offset;
396
397        memcpy(b->buf + write_offset, buf, chunk);
398
399        b->len += chunk;
400
401        assert(b->len <= b->size);
402
403        rest -= chunk;
404        buf += chunk;
405    }
406    while (rest);
407
408    return num;
409}
410
411/*-
412 * non-copying interface: provide pointer to region to write to
413 *   bio_nwrite0:  check how much space is available
414 *   bio_nwrite:   also increase length
415 * (example usage:  bio_nwrite0(), write to buffer, bio_nwrite()
416 *  or just         bio_nwrite(), write to buffer)
417 */
418static ssize_t bio_nwrite0(BIO *bio, char **buf)
419{
420    struct bio_bio_st *b;
421    size_t num;
422    size_t write_offset;
423
424    BIO_clear_retry_flags(bio);
425
426    if (!bio->init)
427        return 0;
428
429    b = bio->ptr;
430    assert(b != NULL);
431    assert(b->peer != NULL);
432    assert(b->buf != NULL);
433
434    b->request = 0;
435    if (b->closed) {
436        BIOerr(BIO_F_BIO_NWRITE0, BIO_R_BROKEN_PIPE);
437        return -1;
438    }
439
440    assert(b->len <= b->size);
441
442    if (b->len == b->size) {
443        BIO_set_retry_write(bio);
444        return -1;
445    }
446
447    num = b->size - b->len;
448    write_offset = b->offset + b->len;
449    if (write_offset >= b->size)
450        write_offset -= b->size;
451    if (write_offset + num > b->size)
452        /*
453         * no ring buffer wrap-around for non-copying interface (to fulfil
454         * the promise by BIO_ctrl_get_write_guarantee, BIO_nwrite may have
455         * to be called twice)
456         */
457        num = b->size - write_offset;
458
459    if (buf != NULL)
460        *buf = b->buf + write_offset;
461    assert(write_offset + num <= b->size);
462
463    return num;
464}
465
466static ssize_t bio_nwrite(BIO *bio, char **buf, size_t num_)
467{
468    struct bio_bio_st *b;
469    ssize_t num, space;
470
471    if (num_ > SSIZE_MAX)
472        num = SSIZE_MAX;
473    else
474        num = (ssize_t) num_;
475
476    space = bio_nwrite0(bio, buf);
477    if (num > space)
478        num = space;
479    if (num <= 0)
480        return num;
481    b = bio->ptr;
482    assert(b != NULL);
483    b->len += num;
484    assert(b->len <= b->size);
485
486    return num;
487}
488
489static long bio_ctrl(BIO *bio, int cmd, long num, void *ptr)
490{
491    long ret;
492    struct bio_bio_st *b = bio->ptr;
493
494    assert(b != NULL);
495
496    switch (cmd) {
497        /* specific CTRL codes */
498
499    case BIO_C_SET_WRITE_BUF_SIZE:
500        if (b->peer) {
501            BIOerr(BIO_F_BIO_CTRL, BIO_R_IN_USE);
502            ret = 0;
503        } else if (num == 0) {
504            BIOerr(BIO_F_BIO_CTRL, BIO_R_INVALID_ARGUMENT);
505            ret = 0;
506        } else {
507            size_t new_size = num;
508
509            if (b->size != new_size) {
510                if (b->buf) {
511                    OPENSSL_free(b->buf);
512                    b->buf = NULL;
513                }
514                b->size = new_size;
515            }
516            ret = 1;
517        }
518        break;
519
520    case BIO_C_GET_WRITE_BUF_SIZE:
521        ret = (long)b->size;
522        break;
523
524    case BIO_C_MAKE_BIO_PAIR:
525        {
526            BIO *other_bio = ptr;
527
528            if (bio_make_pair(bio, other_bio))
529                ret = 1;
530            else
531                ret = 0;
532        }
533        break;
534
535    case BIO_C_DESTROY_BIO_PAIR:
536        /*
537         * Affects both BIOs in the pair -- call just once! Or let
538         * BIO_free(bio1); BIO_free(bio2); do the job.
539         */
540        bio_destroy_pair(bio);
541        ret = 1;
542        break;
543
544    case BIO_C_GET_WRITE_GUARANTEE:
545        /*
546         * How many bytes can the caller feed to the next write without
547         * having to keep any?
548         */
549        if (b->peer == NULL || b->closed)
550            ret = 0;
551        else
552            ret = (long)b->size - b->len;
553        break;
554
555    case BIO_C_GET_READ_REQUEST:
556        /*
557         * If the peer unsuccessfully tried to read, how many bytes were
558         * requested? (As with BIO_CTRL_PENDING, that number can usually be
559         * treated as boolean.)
560         */
561        ret = (long)b->request;
562        break;
563
564    case BIO_C_RESET_READ_REQUEST:
565        /*
566         * Reset request.  (Can be useful after read attempts at the other
567         * side that are meant to be non-blocking, e.g. when probing SSL_read
568         * to see if any data is available.)
569         */
570        b->request = 0;
571        ret = 1;
572        break;
573
574    case BIO_C_SHUTDOWN_WR:
575        /* similar to shutdown(..., SHUT_WR) */
576        b->closed = 1;
577        ret = 1;
578        break;
579
580    case BIO_C_NREAD0:
581        /* prepare for non-copying read */
582        ret = (long)bio_nread0(bio, ptr);
583        break;
584
585    case BIO_C_NREAD:
586        /* non-copying read */
587        ret = (long)bio_nread(bio, ptr, (size_t)num);
588        break;
589
590    case BIO_C_NWRITE0:
591        /* prepare for non-copying write */
592        ret = (long)bio_nwrite0(bio, ptr);
593        break;
594
595    case BIO_C_NWRITE:
596        /* non-copying write */
597        ret = (long)bio_nwrite(bio, ptr, (size_t)num);
598        break;
599
600        /* standard CTRL codes follow */
601
602    case BIO_CTRL_RESET:
603        if (b->buf != NULL) {
604            b->len = 0;
605            b->offset = 0;
606        }
607        ret = 0;
608        break;
609
610    case BIO_CTRL_GET_CLOSE:
611        ret = bio->shutdown;
612        break;
613
614    case BIO_CTRL_SET_CLOSE:
615        bio->shutdown = (int)num;
616        ret = 1;
617        break;
618
619    case BIO_CTRL_PENDING:
620        if (b->peer != NULL) {
621            struct bio_bio_st *peer_b = b->peer->ptr;
622
623            ret = (long)peer_b->len;
624        } else
625            ret = 0;
626        break;
627
628    case BIO_CTRL_WPENDING:
629        if (b->buf != NULL)
630            ret = (long)b->len;
631        else
632            ret = 0;
633        break;
634
635    case BIO_CTRL_DUP:
636        /* See BIO_dup_chain for circumstances we have to expect. */
637        {
638            BIO *other_bio = ptr;
639            struct bio_bio_st *other_b;
640
641            assert(other_bio != NULL);
642            other_b = other_bio->ptr;
643            assert(other_b != NULL);
644
645            assert(other_b->buf == NULL); /* other_bio is always fresh */
646
647            other_b->size = b->size;
648        }
649
650        ret = 1;
651        break;
652
653    case BIO_CTRL_FLUSH:
654        ret = 1;
655        break;
656
657    case BIO_CTRL_EOF:
658        {
659            BIO *other_bio = ptr;
660
661            if (other_bio) {
662                struct bio_bio_st *other_b = other_bio->ptr;
663
664                assert(other_b != NULL);
665                ret = other_b->len == 0 && other_b->closed;
666            } else
667                ret = 1;
668        }
669        break;
670
671    default:
672        ret = 0;
673    }
674    return ret;
675}
676
677static int bio_puts(BIO *bio, const char *str)
678{
679    return bio_write(bio, str, strlen(str));
680}
681
682static int bio_make_pair(BIO *bio1, BIO *bio2)
683{
684    struct bio_bio_st *b1, *b2;
685
686    assert(bio1 != NULL);
687    assert(bio2 != NULL);
688
689    b1 = bio1->ptr;
690    b2 = bio2->ptr;
691
692    if (b1->peer != NULL || b2->peer != NULL) {
693        BIOerr(BIO_F_BIO_MAKE_PAIR, BIO_R_IN_USE);
694        return 0;
695    }
696
697    if (b1->buf == NULL) {
698        b1->buf = OPENSSL_malloc(b1->size);
699        if (b1->buf == NULL) {
700            BIOerr(BIO_F_BIO_MAKE_PAIR, ERR_R_MALLOC_FAILURE);
701            return 0;
702        }
703        b1->len = 0;
704        b1->offset = 0;
705    }
706
707    if (b2->buf == NULL) {
708        b2->buf = OPENSSL_malloc(b2->size);
709        if (b2->buf == NULL) {
710            BIOerr(BIO_F_BIO_MAKE_PAIR, ERR_R_MALLOC_FAILURE);
711            return 0;
712        }
713        b2->len = 0;
714        b2->offset = 0;
715    }
716
717    b1->peer = bio2;
718    b1->closed = 0;
719    b1->request = 0;
720    b2->peer = bio1;
721    b2->closed = 0;
722    b2->request = 0;
723
724    bio1->init = 1;
725    bio2->init = 1;
726
727    return 1;
728}
729
730static void bio_destroy_pair(BIO *bio)
731{
732    struct bio_bio_st *b = bio->ptr;
733
734    if (b != NULL) {
735        BIO *peer_bio = b->peer;
736
737        if (peer_bio != NULL) {
738            struct bio_bio_st *peer_b = peer_bio->ptr;
739
740            assert(peer_b != NULL);
741            assert(peer_b->peer == bio);
742
743            peer_b->peer = NULL;
744            peer_bio->init = 0;
745            assert(peer_b->buf != NULL);
746            peer_b->len = 0;
747            peer_b->offset = 0;
748
749            b->peer = NULL;
750            bio->init = 0;
751            assert(b->buf != NULL);
752            b->len = 0;
753            b->offset = 0;
754        }
755    }
756}
757
758/* Exported convenience functions */
759int BIO_new_bio_pair(BIO **bio1_p, size_t writebuf1,
760                     BIO **bio2_p, size_t writebuf2)
761{
762    BIO *bio1 = NULL, *bio2 = NULL;
763    long r;
764    int ret = 0;
765
766    bio1 = BIO_new(BIO_s_bio());
767    if (bio1 == NULL)
768        goto err;
769    bio2 = BIO_new(BIO_s_bio());
770    if (bio2 == NULL)
771        goto err;
772
773    if (writebuf1) {
774        r = BIO_set_write_buf_size(bio1, writebuf1);
775        if (!r)
776            goto err;
777    }
778    if (writebuf2) {
779        r = BIO_set_write_buf_size(bio2, writebuf2);
780        if (!r)
781            goto err;
782    }
783
784    r = BIO_make_bio_pair(bio1, bio2);
785    if (!r)
786        goto err;
787    ret = 1;
788
789 err:
790    if (ret == 0) {
791        if (bio1) {
792            BIO_free(bio1);
793            bio1 = NULL;
794        }
795        if (bio2) {
796            BIO_free(bio2);
797            bio2 = NULL;
798        }
799    }
800
801    *bio1_p = bio1;
802    *bio2_p = bio2;
803    return ret;
804}
805
806size_t BIO_ctrl_get_write_guarantee(BIO *bio)
807{
808    return BIO_ctrl(bio, BIO_C_GET_WRITE_GUARANTEE, 0, NULL);
809}
810
811size_t BIO_ctrl_get_read_request(BIO *bio)
812{
813    return BIO_ctrl(bio, BIO_C_GET_READ_REQUEST, 0, NULL);
814}
815
816int BIO_ctrl_reset_read_request(BIO *bio)
817{
818    return (BIO_ctrl(bio, BIO_C_RESET_READ_REQUEST, 0, NULL) != 0);
819}
820
821/*
822 * BIO_nread0/nread/nwrite0/nwrite are available only for BIO pairs for now
823 * (conceivably some other BIOs could allow non-copying reads and writes
824 * too.)
825 */
826int BIO_nread0(BIO *bio, char **buf)
827{
828    long ret;
829
830    if (!bio->init) {
831        BIOerr(BIO_F_BIO_NREAD0, BIO_R_UNINITIALIZED);
832        return -2;
833    }
834
835    ret = BIO_ctrl(bio, BIO_C_NREAD0, 0, buf);
836    if (ret > INT_MAX)
837        return INT_MAX;
838    else
839        return (int)ret;
840}
841
842int BIO_nread(BIO *bio, char **buf, int num)
843{
844    int ret;
845
846    if (!bio->init) {
847        BIOerr(BIO_F_BIO_NREAD, BIO_R_UNINITIALIZED);
848        return -2;
849    }
850
851    ret = (int)BIO_ctrl(bio, BIO_C_NREAD, num, buf);
852    if (ret > 0)
853        bio->num_read += ret;
854    return ret;
855}
856
857int BIO_nwrite0(BIO *bio, char **buf)
858{
859    long ret;
860
861    if (!bio->init) {
862        BIOerr(BIO_F_BIO_NWRITE0, BIO_R_UNINITIALIZED);
863        return -2;
864    }
865
866    ret = BIO_ctrl(bio, BIO_C_NWRITE0, 0, buf);
867    if (ret > INT_MAX)
868        return INT_MAX;
869    else
870        return (int)ret;
871}
872
873int BIO_nwrite(BIO *bio, char **buf, int num)
874{
875    int ret;
876
877    if (!bio->init) {
878        BIOerr(BIO_F_BIO_NWRITE, BIO_R_UNINITIALIZED);
879        return -2;
880    }
881
882    ret = BIO_ctrl(bio, BIO_C_NWRITE, num, buf);
883    if (ret > 0)
884        bio->num_write += ret;
885    return ret;
886}
887