aboutsummaryrefslogtreecommitdiff
path: root/openssl/crypto/bio/bss_bio.c
diff options
context:
space:
mode:
Diffstat (limited to 'openssl/crypto/bio/bss_bio.c')
-rw-r--r--openssl/crypto/bio/bss_bio.c924
1 files changed, 924 insertions, 0 deletions
diff --git a/openssl/crypto/bio/bss_bio.c b/openssl/crypto/bio/bss_bio.c
new file mode 100644
index 000000000..76bd48e76
--- /dev/null
+++ b/openssl/crypto/bio/bss_bio.c
@@ -0,0 +1,924 @@
+/* crypto/bio/bss_bio.c -*- Mode: C; c-file-style: "eay" -*- */
+/* ====================================================================
+ * Copyright (c) 1998-2003 The OpenSSL Project. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ * software must display the following acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ * endorse or promote products derived from this software without
+ * prior written permission. For written permission, please contact
+ * openssl-core@openssl.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ * nor may "OpenSSL" appear in their names without prior written
+ * permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ * acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This product includes cryptographic software written by Eric Young
+ * (eay@cryptsoft.com). This product includes software written by Tim
+ * Hudson (tjh@cryptsoft.com).
+ *
+ */
+
+/* Special method for a BIO where the other endpoint is also a BIO
+ * of this kind, handled by the same thread (i.e. the "peer" is actually
+ * ourselves, wearing a different hat).
+ * Such "BIO pairs" are mainly for using the SSL library with I/O interfaces
+ * for which no specific BIO method is available.
+ * See ssl/ssltest.c for some hints on how this can be used. */
+
+/* BIO_DEBUG implies BIO_PAIR_DEBUG */
+#ifdef BIO_DEBUG
+# ifndef BIO_PAIR_DEBUG
+# define BIO_PAIR_DEBUG
+# endif
+#endif
+
+/* disable assert() unless BIO_PAIR_DEBUG has been defined */
+#ifndef BIO_PAIR_DEBUG
+# ifndef NDEBUG
+# define NDEBUG
+# endif
+#endif
+
+#include <assert.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <openssl/bio.h>
+#include <openssl/err.h>
+#include <openssl/crypto.h>
+
+#include "e_os.h"
+
+/* VxWorks defines SSIZE_MAX with an empty value causing compile errors */
+#if defined(OPENSSL_SYS_VXWORKS)
+# undef SSIZE_MAX
+#endif
+#ifndef SSIZE_MAX
+# define SSIZE_MAX INT_MAX
+#endif
+
+static int bio_new(BIO *bio);
+static int bio_free(BIO *bio);
+static int bio_read(BIO *bio, char *buf, int size);
+static int bio_write(BIO *bio, const char *buf, int num);
+static long bio_ctrl(BIO *bio, int cmd, long num, void *ptr);
+static int bio_puts(BIO *bio, const char *str);
+
+static int bio_make_pair(BIO *bio1, BIO *bio2);
+static void bio_destroy_pair(BIO *bio);
+
+static BIO_METHOD methods_biop =
+{
+ BIO_TYPE_BIO,
+ "BIO pair",
+ bio_write,
+ bio_read,
+ bio_puts,
+ NULL /* no bio_gets */,
+ bio_ctrl,
+ bio_new,
+ bio_free,
+ NULL /* no bio_callback_ctrl */
+};
+
+BIO_METHOD *BIO_s_bio(void)
+ {
+ return &methods_biop;
+ }
+
+struct bio_bio_st
+{
+ BIO *peer; /* NULL if buf == NULL.
+ * If peer != NULL, then peer->ptr is also a bio_bio_st,
+ * and its "peer" member points back to us.
+ * peer != NULL iff init != 0 in the BIO. */
+
+ /* This is for what we write (i.e. reading uses peer's struct): */
+ int closed; /* valid iff peer != NULL */
+ size_t len; /* valid iff buf != NULL; 0 if peer == NULL */
+ size_t offset; /* valid iff buf != NULL; 0 if len == 0 */
+ size_t size;
+ char *buf; /* "size" elements (if != NULL) */
+
+ size_t request; /* valid iff peer != NULL; 0 if len != 0,
+ * otherwise set by peer to number of bytes
+ * it (unsuccessfully) tried to read,
+ * never more than buffer space (size-len) warrants. */
+};
+
+static int bio_new(BIO *bio)
+ {
+ struct bio_bio_st *b;
+
+ b = OPENSSL_malloc(sizeof *b);
+ if (b == NULL)
+ return 0;
+
+ b->peer = NULL;
+ b->size = 17*1024; /* enough for one TLS record (just a default) */
+ b->buf = NULL;
+
+ bio->ptr = b;
+ return 1;
+ }
+
+
+static int bio_free(BIO *bio)
+ {
+ struct bio_bio_st *b;
+
+ if (bio == NULL)
+ return 0;
+ b = bio->ptr;
+
+ assert(b != NULL);
+
+ if (b->peer)
+ bio_destroy_pair(bio);
+
+ if (b->buf != NULL)
+ {
+ OPENSSL_free(b->buf);
+ }
+
+ OPENSSL_free(b);
+
+ return 1;
+ }
+
+
+
+static int bio_read(BIO *bio, char *buf, int size_)
+ {
+ size_t size = size_;
+ size_t rest;
+ struct bio_bio_st *b, *peer_b;
+
+ BIO_clear_retry_flags(bio);
+
+ if (!bio->init)
+ return 0;
+
+ b = bio->ptr;
+ assert(b != NULL);
+ assert(b->peer != NULL);
+ peer_b = b->peer->ptr;
+ assert(peer_b != NULL);
+ assert(peer_b->buf != NULL);
+
+ peer_b->request = 0; /* will be set in "retry_read" situation */
+
+ if (buf == NULL || size == 0)
+ return 0;
+
+ if (peer_b->len == 0)
+ {
+ if (peer_b->closed)
+ return 0; /* writer has closed, and no data is left */
+ else
+ {
+ BIO_set_retry_read(bio); /* buffer is empty */
+ if (size <= peer_b->size)
+ peer_b->request = size;
+ else
+ /* don't ask for more than the peer can
+ * deliver in one write */
+ peer_b->request = peer_b->size;
+ return -1;
+ }
+ }
+
+ /* we can read */
+ if (peer_b->len < size)
+ size = peer_b->len;
+
+ /* now read "size" bytes */
+
+ rest = size;
+
+ assert(rest > 0);
+ do /* one or two iterations */
+ {
+ size_t chunk;
+
+ assert(rest <= peer_b->len);
+ if (peer_b->offset + rest <= peer_b->size)
+ chunk = rest;
+ else
+ /* wrap around ring buffer */
+ chunk = peer_b->size - peer_b->offset;
+ assert(peer_b->offset + chunk <= peer_b->size);
+
+ memcpy(buf, peer_b->buf + peer_b->offset, chunk);
+
+ peer_b->len -= chunk;
+ if (peer_b->len)
+ {
+ peer_b->offset += chunk;
+ assert(peer_b->offset <= peer_b->size);
+ if (peer_b->offset == peer_b->size)
+ peer_b->offset = 0;
+ buf += chunk;
+ }
+ else
+ {
+ /* buffer now empty, no need to advance "buf" */
+ assert(chunk == rest);
+ peer_b->offset = 0;
+ }
+ rest -= chunk;
+ }
+ while (rest);
+
+ return size;
+ }
+
+/* non-copying interface: provide pointer to available data in buffer
+ * bio_nread0: return number of available bytes
+ * bio_nread: also advance index
+ * (example usage: bio_nread0(), read from buffer, bio_nread()
+ * or just bio_nread(), read from buffer)
+ */
+/* WARNING: The non-copying interface is largely untested as of yet
+ * and may contain bugs. */
+static ssize_t bio_nread0(BIO *bio, char **buf)
+ {
+ struct bio_bio_st *b, *peer_b;
+ ssize_t num;
+
+ BIO_clear_retry_flags(bio);
+
+ if (!bio->init)
+ return 0;
+
+ b = bio->ptr;
+ assert(b != NULL);
+ assert(b->peer != NULL);
+ peer_b = b->peer->ptr;
+ assert(peer_b != NULL);
+ assert(peer_b->buf != NULL);
+
+ peer_b->request = 0;
+
+ if (peer_b->len == 0)
+ {
+ char dummy;
+
+ /* avoid code duplication -- nothing available for reading */
+ return bio_read(bio, &dummy, 1); /* returns 0 or -1 */
+ }
+
+ num = peer_b->len;
+ if (peer_b->size < peer_b->offset + num)
+ /* no ring buffer wrap-around for non-copying interface */
+ num = peer_b->size - peer_b->offset;
+ assert(num > 0);
+
+ if (buf != NULL)
+ *buf = peer_b->buf + peer_b->offset;
+ return num;
+ }
+
+static ssize_t bio_nread(BIO *bio, char **buf, size_t num_)
+ {
+ struct bio_bio_st *b, *peer_b;
+ ssize_t num, available;
+
+ if (num_ > SSIZE_MAX)
+ num = SSIZE_MAX;
+ else
+ num = (ssize_t)num_;
+
+ available = bio_nread0(bio, buf);
+ if (num > available)
+ num = available;
+ if (num <= 0)
+ return num;
+
+ b = bio->ptr;
+ peer_b = b->peer->ptr;
+
+ peer_b->len -= num;
+ if (peer_b->len)
+ {
+ peer_b->offset += num;
+ assert(peer_b->offset <= peer_b->size);
+ if (peer_b->offset == peer_b->size)
+ peer_b->offset = 0;
+ }
+ else
+ peer_b->offset = 0;
+
+ return num;
+ }
+
+
+static int bio_write(BIO *bio, const char *buf, int num_)
+ {
+ size_t num = num_;
+ size_t rest;
+ struct bio_bio_st *b;
+
+ BIO_clear_retry_flags(bio);
+
+ if (!bio->init || buf == NULL || num == 0)
+ return 0;
+
+ b = bio->ptr;
+ assert(b != NULL);
+ assert(b->peer != NULL);
+ assert(b->buf != NULL);
+
+ b->request = 0;
+ if (b->closed)
+ {
+ /* we already closed */
+ BIOerr(BIO_F_BIO_WRITE, BIO_R_BROKEN_PIPE);
+ return -1;
+ }
+
+ assert(b->len <= b->size);
+
+ if (b->len == b->size)
+ {
+ BIO_set_retry_write(bio); /* buffer is full */
+ return -1;
+ }
+
+ /* we can write */
+ if (num > b->size - b->len)
+ num = b->size - b->len;
+
+ /* now write "num" bytes */
+
+ rest = num;
+
+ assert(rest > 0);
+ do /* one or two iterations */
+ {
+ size_t write_offset;
+ size_t chunk;
+
+ assert(b->len + rest <= b->size);
+
+ write_offset = b->offset + b->len;
+ if (write_offset >= b->size)
+ write_offset -= b->size;
+ /* b->buf[write_offset] is the first byte we can write to. */
+
+ if (write_offset + rest <= b->size)
+ chunk = rest;
+ else
+ /* wrap around ring buffer */
+ chunk = b->size - write_offset;
+
+ memcpy(b->buf + write_offset, buf, chunk);
+
+ b->len += chunk;
+
+ assert(b->len <= b->size);
+
+ rest -= chunk;
+ buf += chunk;
+ }
+ while (rest);
+
+ return num;
+ }
+
+/* non-copying interface: provide pointer to region to write to
+ * bio_nwrite0: check how much space is available
+ * bio_nwrite: also increase length
+ * (example usage: bio_nwrite0(), write to buffer, bio_nwrite()
+ * or just bio_nwrite(), write to buffer)
+ */
+static ssize_t bio_nwrite0(BIO *bio, char **buf)
+ {
+ struct bio_bio_st *b;
+ size_t num;
+ size_t write_offset;
+
+ BIO_clear_retry_flags(bio);
+
+ if (!bio->init)
+ return 0;
+
+ b = bio->ptr;
+ assert(b != NULL);
+ assert(b->peer != NULL);
+ assert(b->buf != NULL);
+
+ b->request = 0;
+ if (b->closed)
+ {
+ BIOerr(BIO_F_BIO_NWRITE0, BIO_R_BROKEN_PIPE);
+ return -1;
+ }
+
+ assert(b->len <= b->size);
+
+ if (b->len == b->size)
+ {
+ BIO_set_retry_write(bio);
+ return -1;
+ }
+
+ num = b->size - b->len;
+ write_offset = b->offset + b->len;
+ if (write_offset >= b->size)
+ write_offset -= b->size;
+ if (write_offset + num > b->size)
+ /* no ring buffer wrap-around for non-copying interface
+ * (to fulfil the promise by BIO_ctrl_get_write_guarantee,
+ * BIO_nwrite may have to be called twice) */
+ num = b->size - write_offset;
+
+ if (buf != NULL)
+ *buf = b->buf + write_offset;
+ assert(write_offset + num <= b->size);
+
+ return num;
+ }
+
+static ssize_t bio_nwrite(BIO *bio, char **buf, size_t num_)
+ {
+ struct bio_bio_st *b;
+ ssize_t num, space;
+
+ if (num_ > SSIZE_MAX)
+ num = SSIZE_MAX;
+ else
+ num = (ssize_t)num_;
+
+ space = bio_nwrite0(bio, buf);
+ if (num > space)
+ num = space;
+ if (num <= 0)
+ return num;
+ b = bio->ptr;
+ assert(b != NULL);
+ b->len += num;
+ assert(b->len <= b->size);
+
+ return num;
+ }
+
+
+static long bio_ctrl(BIO *bio, int cmd, long num, void *ptr)
+ {
+ long ret;
+ struct bio_bio_st *b = bio->ptr;
+
+ assert(b != NULL);
+
+ switch (cmd)
+ {
+ /* specific CTRL codes */
+
+ case BIO_C_SET_WRITE_BUF_SIZE:
+ if (b->peer)
+ {
+ BIOerr(BIO_F_BIO_CTRL, BIO_R_IN_USE);
+ ret = 0;
+ }
+ else if (num == 0)
+ {
+ BIOerr(BIO_F_BIO_CTRL, BIO_R_INVALID_ARGUMENT);
+ ret = 0;
+ }
+ else
+ {
+ size_t new_size = num;
+
+ if (b->size != new_size)
+ {
+ if (b->buf)
+ {
+ OPENSSL_free(b->buf);
+ b->buf = NULL;
+ }
+ b->size = new_size;
+ }
+ ret = 1;
+ }
+ break;
+
+ case BIO_C_GET_WRITE_BUF_SIZE:
+ ret = (long) b->size;
+ break;
+
+ case BIO_C_MAKE_BIO_PAIR:
+ {
+ BIO *other_bio = ptr;
+
+ if (bio_make_pair(bio, other_bio))
+ ret = 1;
+ else
+ ret = 0;
+ }
+ break;
+
+ case BIO_C_DESTROY_BIO_PAIR:
+ /* Affects both BIOs in the pair -- call just once!
+ * Or let BIO_free(bio1); BIO_free(bio2); do the job. */
+ bio_destroy_pair(bio);
+ ret = 1;
+ break;
+
+ case BIO_C_GET_WRITE_GUARANTEE:
+ /* How many bytes can the caller feed to the next write
+ * without having to keep any? */
+ if (b->peer == NULL || b->closed)
+ ret = 0;
+ else
+ ret = (long) b->size - b->len;
+ break;
+
+ case BIO_C_GET_READ_REQUEST:
+ /* If the peer unsuccessfully tried to read, how many bytes
+ * were requested? (As with BIO_CTRL_PENDING, that number
+ * can usually be treated as boolean.) */
+ ret = (long) b->request;
+ break;
+
+ case BIO_C_RESET_READ_REQUEST:
+ /* Reset request. (Can be useful after read attempts
+ * at the other side that are meant to be non-blocking,
+ * e.g. when probing SSL_read to see if any data is
+ * available.) */
+ b->request = 0;
+ ret = 1;
+ break;
+
+ case BIO_C_SHUTDOWN_WR:
+ /* similar to shutdown(..., SHUT_WR) */
+ b->closed = 1;
+ ret = 1;
+ break;
+
+ case BIO_C_NREAD0:
+ /* prepare for non-copying read */
+ ret = (long) bio_nread0(bio, ptr);
+ break;
+
+ case BIO_C_NREAD:
+ /* non-copying read */
+ ret = (long) bio_nread(bio, ptr, (size_t) num);
+ break;
+
+ case BIO_C_NWRITE0:
+ /* prepare for non-copying write */
+ ret = (long) bio_nwrite0(bio, ptr);
+ break;
+
+ case BIO_C_NWRITE:
+ /* non-copying write */
+ ret = (long) bio_nwrite(bio, ptr, (size_t) num);
+ break;
+
+
+ /* standard CTRL codes follow */
+
+ case BIO_CTRL_RESET:
+ if (b->buf != NULL)
+ {
+ b->len = 0;
+ b->offset = 0;
+ }
+ ret = 0;
+ break;
+
+ case BIO_CTRL_GET_CLOSE:
+ ret = bio->shutdown;
+ break;
+
+ case BIO_CTRL_SET_CLOSE:
+ bio->shutdown = (int) num;
+ ret = 1;
+ break;
+
+ case BIO_CTRL_PENDING:
+ if (b->peer != NULL)
+ {
+ struct bio_bio_st *peer_b = b->peer->ptr;
+
+ ret = (long) peer_b->len;
+ }
+ else
+ ret = 0;
+ break;
+
+ case BIO_CTRL_WPENDING:
+ if (b->buf != NULL)
+ ret = (long) b->len;
+ else
+ ret = 0;
+ break;
+
+ case BIO_CTRL_DUP:
+ /* See BIO_dup_chain for circumstances we have to expect. */
+ {
+ BIO *other_bio = ptr;
+ struct bio_bio_st *other_b;
+
+ assert(other_bio != NULL);
+ other_b = other_bio->ptr;
+ assert(other_b != NULL);
+
+ assert(other_b->buf == NULL); /* other_bio is always fresh */
+
+ other_b->size = b->size;
+ }
+
+ ret = 1;
+ break;
+
+ case BIO_CTRL_FLUSH:
+ ret = 1;
+ break;
+
+ case BIO_CTRL_EOF:
+ {
+ BIO *other_bio = ptr;
+
+ if (other_bio)
+ {
+ struct bio_bio_st *other_b = other_bio->ptr;
+
+ assert(other_b != NULL);
+ ret = other_b->len == 0 && other_b->closed;
+ }
+ else
+ ret = 1;
+ }
+ break;
+
+ default:
+ ret = 0;
+ }
+ return ret;
+ }
+
+static int bio_puts(BIO *bio, const char *str)
+ {
+ return bio_write(bio, str, strlen(str));
+ }
+
+
+static int bio_make_pair(BIO *bio1, BIO *bio2)
+ {
+ struct bio_bio_st *b1, *b2;
+
+ assert(bio1 != NULL);
+ assert(bio2 != NULL);
+
+ b1 = bio1->ptr;
+ b2 = bio2->ptr;
+
+ if (b1->peer != NULL || b2->peer != NULL)
+ {
+ BIOerr(BIO_F_BIO_MAKE_PAIR, BIO_R_IN_USE);
+ return 0;
+ }
+
+ if (b1->buf == NULL)
+ {
+ b1->buf = OPENSSL_malloc(b1->size);
+ if (b1->buf == NULL)
+ {
+ BIOerr(BIO_F_BIO_MAKE_PAIR, ERR_R_MALLOC_FAILURE);
+ return 0;
+ }
+ b1->len = 0;
+ b1->offset = 0;
+ }
+
+ if (b2->buf == NULL)
+ {
+ b2->buf = OPENSSL_malloc(b2->size);
+ if (b2->buf == NULL)
+ {
+ BIOerr(BIO_F_BIO_MAKE_PAIR, ERR_R_MALLOC_FAILURE);
+ return 0;
+ }
+ b2->len = 0;
+ b2->offset = 0;
+ }
+
+ b1->peer = bio2;
+ b1->closed = 0;
+ b1->request = 0;
+ b2->peer = bio1;
+ b2->closed = 0;
+ b2->request = 0;
+
+ bio1->init = 1;
+ bio2->init = 1;
+
+ return 1;
+ }
+
+static void bio_destroy_pair(BIO *bio)
+ {
+ struct bio_bio_st *b = bio->ptr;
+
+ if (b != NULL)
+ {
+ BIO *peer_bio = b->peer;
+
+ if (peer_bio != NULL)
+ {
+ struct bio_bio_st *peer_b = peer_bio->ptr;
+
+ assert(peer_b != NULL);
+ assert(peer_b->peer == bio);
+
+ peer_b->peer = NULL;
+ peer_bio->init = 0;
+ assert(peer_b->buf != NULL);
+ peer_b->len = 0;
+ peer_b->offset = 0;
+
+ b->peer = NULL;
+ bio->init = 0;
+ assert(b->buf != NULL);
+ b->len = 0;
+ b->offset = 0;
+ }
+ }
+ }
+
+
+/* Exported convenience functions */
+int BIO_new_bio_pair(BIO **bio1_p, size_t writebuf1,
+ BIO **bio2_p, size_t writebuf2)
+ {
+ BIO *bio1 = NULL, *bio2 = NULL;
+ long r;
+ int ret = 0;
+
+ bio1 = BIO_new(BIO_s_bio());
+ if (bio1 == NULL)
+ goto err;
+ bio2 = BIO_new(BIO_s_bio());
+ if (bio2 == NULL)
+ goto err;
+
+ if (writebuf1)
+ {
+ r = BIO_set_write_buf_size(bio1, writebuf1);
+ if (!r)
+ goto err;
+ }
+ if (writebuf2)
+ {
+ r = BIO_set_write_buf_size(bio2, writebuf2);
+ if (!r)
+ goto err;
+ }
+
+ r = BIO_make_bio_pair(bio1, bio2);
+ if (!r)
+ goto err;
+ ret = 1;
+
+ err:
+ if (ret == 0)
+ {
+ if (bio1)
+ {
+ BIO_free(bio1);
+ bio1 = NULL;
+ }
+ if (bio2)
+ {
+ BIO_free(bio2);
+ bio2 = NULL;
+ }
+ }
+
+ *bio1_p = bio1;
+ *bio2_p = bio2;
+ return ret;
+ }
+
+size_t BIO_ctrl_get_write_guarantee(BIO *bio)
+ {
+ return BIO_ctrl(bio, BIO_C_GET_WRITE_GUARANTEE, 0, NULL);
+ }
+
+size_t BIO_ctrl_get_read_request(BIO *bio)
+ {
+ return BIO_ctrl(bio, BIO_C_GET_READ_REQUEST, 0, NULL);
+ }
+
+int BIO_ctrl_reset_read_request(BIO *bio)
+ {
+ return (BIO_ctrl(bio, BIO_C_RESET_READ_REQUEST, 0, NULL) != 0);
+ }
+
+
+/* BIO_nread0/nread/nwrite0/nwrite are available only for BIO pairs for now
+ * (conceivably some other BIOs could allow non-copying reads and writes too.)
+ */
+int BIO_nread0(BIO *bio, char **buf)
+ {
+ long ret;
+
+ if (!bio->init)
+ {
+ BIOerr(BIO_F_BIO_NREAD0, BIO_R_UNINITIALIZED);
+ return -2;
+ }
+
+ ret = BIO_ctrl(bio, BIO_C_NREAD0, 0, buf);
+ if (ret > INT_MAX)
+ return INT_MAX;
+ else
+ return (int) ret;
+ }
+
+int BIO_nread(BIO *bio, char **buf, int num)
+ {
+ int ret;
+
+ if (!bio->init)
+ {
+ BIOerr(BIO_F_BIO_NREAD, BIO_R_UNINITIALIZED);
+ return -2;
+ }
+
+ ret = (int) BIO_ctrl(bio, BIO_C_NREAD, num, buf);
+ if (ret > 0)
+ bio->num_read += ret;
+ return ret;
+ }
+
+int BIO_nwrite0(BIO *bio, char **buf)
+ {
+ long ret;
+
+ if (!bio->init)
+ {
+ BIOerr(BIO_F_BIO_NWRITE0, BIO_R_UNINITIALIZED);
+ return -2;
+ }
+
+ ret = BIO_ctrl(bio, BIO_C_NWRITE0, 0, buf);
+ if (ret > INT_MAX)
+ return INT_MAX;
+ else
+ return (int) ret;
+ }
+
+int BIO_nwrite(BIO *bio, char **buf, int num)
+ {
+ int ret;
+
+ if (!bio->init)
+ {
+ BIOerr(BIO_F_BIO_NWRITE, BIO_R_UNINITIALIZED);
+ return -2;
+ }
+
+ ret = BIO_ctrl(bio, BIO_C_NWRITE, num, buf);
+ if (ret > 0)
+ bio->num_write += ret;
+ return ret;
+ }