Backport ossl_ssize_t type from HEAD.
[openssl.git] / crypto / bio / bss_bio.c
index 84b91b5778f6981bd697d5ae51ebb675dd5258bf..52ef0ebcb3e59f57d317041f7f7bf44a245ad0a3 100644 (file)
 /* crypto/bio/bss_bio.c  -*- Mode: C; c-file-style: "eay" -*- */
-
-/*  *** Not yet finished (or even tested). *** */
+/* ====================================================================
+ * 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.
+ * 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. */
+ * 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, char *buf, int num);
-static long bio_ctrl(BIO *bio, int cmd, long num, char *ptr);
-static int bio_puts(BIO *bio, char *str);
+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);
@@ -34,7 +113,8 @@ static BIO_METHOD methods_biop =
        NULL /* no bio_gets */,
        bio_ctrl,
        bio_new,
-       bio_free
+       bio_free,
+       NULL /* no bio_callback_ctrl */
 };
 
 BIO_METHOD *BIO_s_bio(void)
@@ -45,23 +125,28 @@ BIO_METHOD *BIO_s_bio(void)
 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. */
+                       * 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 */
+       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) */
+       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 = Malloc(sizeof *b);
+       b = OPENSSL_malloc(sizeof *b);
        if (b == NULL)
                return 0;
 
@@ -69,6 +154,7 @@ static int bio_new(BIO *bio)
        b->size = 17*1024; /* enough for one TLS record (just a default) */
        b->buf = NULL;
 
+       bio->ptr = b;
        return 1;
        }
 
@@ -88,29 +174,333 @@ static int bio_free(BIO *bio)
        
        if (b->buf != NULL)
                {
-               Free(b->buf);
+               OPENSSL_free(b->buf);
                }
 
-       Free(b);
+       OPENSSL_free(b);
 
        return 1;
        }
 
 
 
-static int bio_read(BIO *bio, char *buf, int size)
+static int bio_read(BIO *bio, char *buf, int size_)
        {
-       /* XXX */
-       return -1;
+       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;
        }
 
-static int bio_write(BIO *bio, char *buf, int num)
+/* 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 ossl_ssize_t bio_nread0(BIO *bio, char **buf)
        {
-       /* XXX */
-       return -1;
+       struct bio_bio_st *b, *peer_b;
+       ossl_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 ossl_ssize_t bio_nread(BIO *bio, char **buf, size_t num_)
+       {
+       struct bio_bio_st *b, *peer_b;
+       ossl_ssize_t num, available;
+
+       if (num_ > SSIZE_MAX)
+               num = SSIZE_MAX;
+       else
+               num = (ossl_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;
        
-static long bio_ctrl(BIO *bio, int cmd, long num, char *ptr)
+       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 ossl_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 ossl_ssize_t bio_nwrite(BIO *bio, char **buf, size_t num_)
+       {
+       struct bio_bio_st *b;
+       ossl_ssize_t num, space;
+
+       if (num_ > SSIZE_MAX)
+               num = SSIZE_MAX;
+       else
+               num = (ossl_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;
@@ -119,12 +509,111 @@ static long bio_ctrl(BIO *bio, int cmd, long num, char *ptr)
 
        switch (cmd)
                {
-               /* XXX Additional commands: */
-               /* - Set buffer size */
-               /* - make pair */
-               /* - destroy pair */
-               /* - get number of bytes that the next write will accept */
-               /* - send "close" */
+       /* 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)
@@ -147,7 +636,7 @@ static long bio_ctrl(BIO *bio, int cmd, long num, char *ptr)
        case BIO_CTRL_PENDING:
                if (b->peer != NULL)
                        {
-                       struct bio_bio_st *peer_b =b->peer->ptr;
+                       struct bio_bio_st *peer_b = b->peer->ptr;
                        
                        ret = (long) peer_b->len;
                        }
@@ -163,25 +652,55 @@ static long bio_ctrl(BIO *bio, int cmd, long num, char *ptr)
                break;
 
        case BIO_CTRL_DUP:
-               /* XXX */
+               /* 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, char *str)
+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;
@@ -198,9 +717,9 @@ static int bio_make_pair(BIO *bio1, BIO *bio2)
                return 0;
                }
        
-       if (b1->buf != NULL)
+       if (b1->buf == NULL)
                {
-               b1->buf = Malloc(b1->size);
+               b1->buf = OPENSSL_malloc(b1->size);
                if (b1->buf == NULL)
                        {
                        BIOerr(BIO_F_BIO_MAKE_PAIR, ERR_R_MALLOC_FAILURE);
@@ -210,9 +729,9 @@ static int bio_make_pair(BIO *bio1, BIO *bio2)
                b1->offset = 0;
                }
        
-       if (b2->buf != NULL)
+       if (b2->buf == NULL)
                {
-               b2->buf = Malloc(b2->size);
+               b2->buf = OPENSSL_malloc(b2->size);
                if (b2->buf == NULL)
                        {
                        BIOerr(BIO_F_BIO_MAKE_PAIR, ERR_R_MALLOC_FAILURE);
@@ -223,7 +742,11 @@ static int bio_make_pair(BIO *bio1, BIO *bio2)
                }
        
        b1->peer = bio2;
+       b1->closed = 0;
+       b1->request = 0;
        b2->peer = bio1;
+       b2->closed = 0;
+       b2->request = 0;
 
        bio1->init = 1;
        bio2->init = 1;
@@ -260,3 +783,142 @@ static void bio_destroy_pair(BIO *bio)
                        }
                }
        }
+
+/* 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;
+       }