1 /* crypto/bio/bss_bio.c -*- Mode: C; c-file-style: "eay" -*- */
2 /* ====================================================================
3 * Copyright (c) 1998-2003 The OpenSSL Project. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
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
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/)"
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.
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.
31 * 6. Redistributions of any form whatsoever must retain the following
33 * "This product includes software developed by the OpenSSL Project
34 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
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 * ====================================================================
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).
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.
64 /* BIO_DEBUG implies BIO_PAIR_DEBUG */
66 # ifndef BIO_PAIR_DEBUG
67 # define BIO_PAIR_DEBUG
71 /* disable assert() unless BIO_PAIR_DEBUG has been defined */
72 #ifndef BIO_PAIR_DEBUG
83 #include <openssl/bio.h>
84 #include <openssl/err.h>
85 #include <openssl/crypto.h>
89 /* VxWorks defines SSIZE_MAX with an empty value causing compile errors */
90 #if defined(OPENSSL_SYS_VXWORKS)
94 # define SSIZE_MAX INT_MAX
97 static int bio_new(BIO
*bio
);
98 static int bio_free(BIO
*bio
);
99 static int bio_read(BIO
*bio
, char *buf
, int size
);
100 static int bio_write(BIO
*bio
, const char *buf
, int num
);
101 static long bio_ctrl(BIO
*bio
, int cmd
, long num
, void *ptr
);
102 static int bio_puts(BIO
*bio
, const char *str
);
104 static int bio_make_pair(BIO
*bio1
, BIO
*bio2
);
105 static void bio_destroy_pair(BIO
*bio
);
107 static BIO_METHOD methods_biop
= {
113 NULL
/* no bio_gets */ ,
117 NULL
/* no bio_callback_ctrl */
120 BIO_METHOD
*BIO_s_bio(void)
122 return &methods_biop
;
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 */
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)
143 static int bio_new(BIO
*bio
)
145 struct bio_bio_st
*b
;
147 b
= OPENSSL_malloc(sizeof *b
);
152 /* enough for one TLS record (just a default) */
160 static int bio_free(BIO
*bio
)
162 struct bio_bio_st
*b
;
171 bio_destroy_pair(bio
);
173 if (b
->buf
!= NULL
) {
174 OPENSSL_free(b
->buf
);
182 static int bio_read(BIO
*bio
, char *buf
, int size_
)
186 struct bio_bio_st
*b
, *peer_b
;
188 BIO_clear_retry_flags(bio
);
195 assert(b
->peer
!= NULL
);
196 peer_b
= b
->peer
->ptr
;
197 assert(peer_b
!= NULL
);
198 assert(peer_b
->buf
!= NULL
);
200 peer_b
->request
= 0; /* will be set in "retry_read" situation */
202 if (buf
== NULL
|| size
== 0)
205 if (peer_b
->len
== 0) {
207 return 0; /* writer has closed, and no data is left */
209 BIO_set_retry_read(bio
); /* buffer is empty */
210 if (size
<= peer_b
->size
)
211 peer_b
->request
= size
;
214 * don't ask for more than the peer can deliver in one write
216 peer_b
->request
= peer_b
->size
;
222 if (peer_b
->len
< size
)
225 /* now read "size" bytes */
230 do { /* one or two iterations */
233 assert(rest
<= peer_b
->len
);
234 if (peer_b
->offset
+ rest
<= peer_b
->size
)
237 /* wrap around ring buffer */
238 chunk
= peer_b
->size
- peer_b
->offset
;
239 assert(peer_b
->offset
+ chunk
<= peer_b
->size
);
241 memcpy(buf
, peer_b
->buf
+ peer_b
->offset
, chunk
);
243 peer_b
->len
-= chunk
;
245 peer_b
->offset
+= chunk
;
246 assert(peer_b
->offset
<= peer_b
->size
);
247 if (peer_b
->offset
== peer_b
->size
)
251 /* buffer now empty, no need to advance "buf" */
252 assert(chunk
== rest
);
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)
270 * WARNING: The non-copying interface is largely untested as of yet and may
273 static ossl_ssize_t
bio_nread0(BIO
*bio
, char **buf
)
275 struct bio_bio_st
*b
, *peer_b
;
278 BIO_clear_retry_flags(bio
);
285 assert(b
->peer
!= NULL
);
286 peer_b
= b
->peer
->ptr
;
287 assert(peer_b
!= NULL
);
288 assert(peer_b
->buf
!= NULL
);
292 if (peer_b
->len
== 0) {
295 /* avoid code duplication -- nothing available for reading */
296 return bio_read(bio
, &dummy
, 1); /* returns 0 or -1 */
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
;
306 *buf
= peer_b
->buf
+ peer_b
->offset
;
310 static ossl_ssize_t
bio_nread(BIO
*bio
, char **buf
, size_t num_
)
312 struct bio_bio_st
*b
, *peer_b
;
313 ossl_ssize_t num
, available
;
315 if (num_
> SSIZE_MAX
)
318 num
= (ossl_ssize_t
) num_
;
320 available
= bio_nread0(bio
, buf
);
327 peer_b
= b
->peer
->ptr
;
331 peer_b
->offset
+= num
;
332 assert(peer_b
->offset
<= peer_b
->size
);
333 if (peer_b
->offset
== peer_b
->size
)
341 static int bio_write(BIO
*bio
, const char *buf
, int num_
)
345 struct bio_bio_st
*b
;
347 BIO_clear_retry_flags(bio
);
349 if (!bio
->init
|| buf
== NULL
|| num
== 0)
354 assert(b
->peer
!= NULL
);
355 assert(b
->buf
!= NULL
);
359 /* we already closed */
360 BIOerr(BIO_F_BIO_WRITE
, BIO_R_BROKEN_PIPE
);
364 assert(b
->len
<= b
->size
);
366 if (b
->len
== b
->size
) {
367 BIO_set_retry_write(bio
); /* buffer is full */
372 if (num
> b
->size
- b
->len
)
373 num
= b
->size
- b
->len
;
375 /* now write "num" bytes */
380 do { /* one or two iterations */
384 assert(b
->len
+ rest
<= b
->size
);
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. */
391 if (write_offset
+ rest
<= b
->size
)
394 /* wrap around ring buffer */
395 chunk
= b
->size
- write_offset
;
397 memcpy(b
->buf
+ write_offset
, buf
, chunk
);
401 assert(b
->len
<= b
->size
);
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)
418 static ossl_ssize_t
bio_nwrite0(BIO
*bio
, char **buf
)
420 struct bio_bio_st
*b
;
424 BIO_clear_retry_flags(bio
);
431 assert(b
->peer
!= NULL
);
432 assert(b
->buf
!= NULL
);
436 BIOerr(BIO_F_BIO_NWRITE0
, BIO_R_BROKEN_PIPE
);
440 assert(b
->len
<= b
->size
);
442 if (b
->len
== b
->size
) {
443 BIO_set_retry_write(bio
);
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
)
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)
457 num
= b
->size
- write_offset
;
460 *buf
= b
->buf
+ write_offset
;
461 assert(write_offset
+ num
<= b
->size
);
466 static ossl_ssize_t
bio_nwrite(BIO
*bio
, char **buf
, size_t num_
)
468 struct bio_bio_st
*b
;
469 ossl_ssize_t num
, space
;
471 if (num_
> SSIZE_MAX
)
474 num
= (ossl_ssize_t
) num_
;
476 space
= bio_nwrite0(bio
, buf
);
484 assert(b
->len
<= b
->size
);
489 static long bio_ctrl(BIO
*bio
, int cmd
, long num
, void *ptr
)
492 struct bio_bio_st
*b
= bio
->ptr
;
497 /* specific CTRL codes */
499 case BIO_C_SET_WRITE_BUF_SIZE
:
501 BIOerr(BIO_F_BIO_CTRL
, BIO_R_IN_USE
);
503 } else if (num
== 0) {
504 BIOerr(BIO_F_BIO_CTRL
, BIO_R_INVALID_ARGUMENT
);
507 size_t new_size
= num
;
509 if (b
->size
!= new_size
) {
511 OPENSSL_free(b
->buf
);
520 case BIO_C_GET_WRITE_BUF_SIZE
:
524 case BIO_C_MAKE_BIO_PAIR
:
526 BIO
*other_bio
= ptr
;
528 if (bio_make_pair(bio
, other_bio
))
535 case BIO_C_DESTROY_BIO_PAIR
:
537 * Affects both BIOs in the pair -- call just once! Or let
538 * BIO_free(bio1); BIO_free(bio2); do the job.
540 bio_destroy_pair(bio
);
544 case BIO_C_GET_WRITE_GUARANTEE
:
546 * How many bytes can the caller feed to the next write without
547 * having to keep any?
549 if (b
->peer
== NULL
|| b
->closed
)
552 ret
= (long)b
->size
- b
->len
;
555 case BIO_C_GET_READ_REQUEST
:
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.)
561 ret
= (long)b
->request
;
564 case BIO_C_RESET_READ_REQUEST
:
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.)
574 case BIO_C_SHUTDOWN_WR
:
575 /* similar to shutdown(..., SHUT_WR) */
581 /* prepare for non-copying read */
582 ret
= (long)bio_nread0(bio
, ptr
);
586 /* non-copying read */
587 ret
= (long)bio_nread(bio
, ptr
, (size_t)num
);
591 /* prepare for non-copying write */
592 ret
= (long)bio_nwrite0(bio
, ptr
);
596 /* non-copying write */
597 ret
= (long)bio_nwrite(bio
, ptr
, (size_t)num
);
600 /* standard CTRL codes follow */
603 if (b
->buf
!= NULL
) {
610 case BIO_CTRL_GET_CLOSE
:
614 case BIO_CTRL_SET_CLOSE
:
615 bio
->shutdown
= (int)num
;
619 case BIO_CTRL_PENDING
:
620 if (b
->peer
!= NULL
) {
621 struct bio_bio_st
*peer_b
= b
->peer
->ptr
;
623 ret
= (long)peer_b
->len
;
628 case BIO_CTRL_WPENDING
:
636 /* See BIO_dup_chain for circumstances we have to expect. */
638 BIO
*other_bio
= ptr
;
639 struct bio_bio_st
*other_b
;
641 assert(other_bio
!= NULL
);
642 other_b
= other_bio
->ptr
;
643 assert(other_b
!= NULL
);
645 assert(other_b
->buf
== NULL
); /* other_bio is always fresh */
647 other_b
->size
= b
->size
;
659 BIO
*other_bio
= ptr
;
662 struct bio_bio_st
*other_b
= other_bio
->ptr
;
664 assert(other_b
!= NULL
);
665 ret
= other_b
->len
== 0 && other_b
->closed
;
677 static int bio_puts(BIO
*bio
, const char *str
)
679 return bio_write(bio
, str
, strlen(str
));
682 static int bio_make_pair(BIO
*bio1
, BIO
*bio2
)
684 struct bio_bio_st
*b1
, *b2
;
686 assert(bio1
!= NULL
);
687 assert(bio2
!= NULL
);
692 if (b1
->peer
!= NULL
|| b2
->peer
!= NULL
) {
693 BIOerr(BIO_F_BIO_MAKE_PAIR
, BIO_R_IN_USE
);
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
);
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
);
730 static void bio_destroy_pair(BIO
*bio
)
732 struct bio_bio_st
*b
= bio
->ptr
;
735 BIO
*peer_bio
= b
->peer
;
737 if (peer_bio
!= NULL
) {
738 struct bio_bio_st
*peer_b
= peer_bio
->ptr
;
740 assert(peer_b
!= NULL
);
741 assert(peer_b
->peer
== bio
);
745 assert(peer_b
->buf
!= NULL
);
751 assert(b
->buf
!= NULL
);
758 /* Exported convenience functions */
759 int BIO_new_bio_pair(BIO
**bio1_p
, size_t writebuf1
,
760 BIO
**bio2_p
, size_t writebuf2
)
762 BIO
*bio1
= NULL
, *bio2
= NULL
;
766 bio1
= BIO_new(BIO_s_bio());
769 bio2
= BIO_new(BIO_s_bio());
774 r
= BIO_set_write_buf_size(bio1
, writebuf1
);
779 r
= BIO_set_write_buf_size(bio2
, writebuf2
);
784 r
= BIO_make_bio_pair(bio1
, bio2
);
802 size_t BIO_ctrl_get_write_guarantee(BIO
*bio
)
804 return BIO_ctrl(bio
, BIO_C_GET_WRITE_GUARANTEE
, 0, NULL
);
807 size_t BIO_ctrl_get_read_request(BIO
*bio
)
809 return BIO_ctrl(bio
, BIO_C_GET_READ_REQUEST
, 0, NULL
);
812 int BIO_ctrl_reset_read_request(BIO
*bio
)
814 return (BIO_ctrl(bio
, BIO_C_RESET_READ_REQUEST
, 0, NULL
) != 0);
818 * BIO_nread0/nread/nwrite0/nwrite are available only for BIO pairs for now
819 * (conceivably some other BIOs could allow non-copying reads and writes
822 int BIO_nread0(BIO
*bio
, char **buf
)
827 BIOerr(BIO_F_BIO_NREAD0
, BIO_R_UNINITIALIZED
);
831 ret
= BIO_ctrl(bio
, BIO_C_NREAD0
, 0, buf
);
838 int BIO_nread(BIO
*bio
, char **buf
, int num
)
843 BIOerr(BIO_F_BIO_NREAD
, BIO_R_UNINITIALIZED
);
847 ret
= (int)BIO_ctrl(bio
, BIO_C_NREAD
, num
, buf
);
849 bio
->num_read
+= ret
;
853 int BIO_nwrite0(BIO
*bio
, char **buf
)
858 BIOerr(BIO_F_BIO_NWRITE0
, BIO_R_UNINITIALIZED
);
862 ret
= BIO_ctrl(bio
, BIO_C_NWRITE0
, 0, buf
);
869 int BIO_nwrite(BIO
*bio
, char **buf
, int num
)
874 BIOerr(BIO_F_BIO_NWRITE
, BIO_R_UNINITIALIZED
);
878 ret
= BIO_ctrl(bio
, BIO_C_NWRITE
, num
, buf
);
880 bio
->num_write
+= ret
;