text: /* ssl/bio_ssl.c */
  /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
   * All rights reserved.
   *
   * This package is an SSL implementation written
   * by Eric Young (eay@cryptsoft.com).
   * The implementation was written so as to conform with Netscapes SSL.
   *
   * This library is free for commercial and non-commercial use as long as
   * the following conditions are aheared to.  The following conditions
   * apply to all code found in this distribution, be it the RC4, RSA,
   * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
   * included with this distribution is covered by the same copyright terms
   * except that the holder is Tim Hudson (tjh@cryptsoft.com).
   *
   * Copyright remains Eric Young's, and as such any Copyright notices in
   * the code are not to be removed.
   * If this package is used in a product, Eric Young should be given attribution
   * as the author of the parts of the library used.
   * This can be in the form of a textual message at program startup or
   * in documentation (online or textual) provided with the package.
   *
   * 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 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 acknowledgement:
   *    "This product includes cryptographic software written by
   *     Eric Young (eay@cryptsoft.com)"
   *    The word 'cryptographic' can be left out if the rouines from the library
   *    being used are not cryptographic related :-).
   * 4. If you include any Windows specific code (or a derivative thereof) from
   *    the apps directory (application code) you must include an acknowledgement:
   *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
   *
   * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
   * ANY EXPRESS 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 AUTHOR OR 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.
   *
   * The licence and distribution terms for any publically available version or
   * derivative of this code cannot be changed.  i.e. this code cannot simply be
   * copied and put under another distribution licence
   * [including the GNU Public Licence.]
   */
  
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <errno.h>
  #include <openssl/crypto.h>
  #include <openssl/bio.h>
  #include <openssl/err.h>
  #include "ssl_locl.h"
  
  static int ssl_write(BIO *h, const char *buf, int num);
  static int ssl_read(BIO *h, char *buf, int size);
  static int ssl_puts(BIO *h, const char *str);
  static long ssl_ctrl(BIO *h, int cmd, long arg1, void *arg2);
  static int ssl_new(BIO *h);
  static int ssl_free(BIO *data);
  static long ssl_callback_ctrl(BIO *h, int cmd, bio_info_cb *fp);
  typedef struct bio_ssl_st {
      SSL *ssl;                   /* The ssl handle :-) */
      /* re-negotiate every time the total number of bytes is this size */
      int num_renegotiates;
      unsigned long renegotiate_count;
      unsigned long byte_count;
      unsigned long renegotiate_timeout;
      unsigned long last_time;
  } BIO_SSL;
  
  static BIO_METHOD methods_sslp = {
      BIO_TYPE_SSL, "ssl",
      ssl_write,
      ssl_read,
      ssl_puts,
      NULL,                       /* ssl_gets, */
      ssl_ctrl,
      ssl_new,
      ssl_free,
      ssl_callback_ctrl,
  };
  
  BIO_METHOD *BIO_f_ssl(void)
  {
      return (&methods_sslp);
  }
  
  static int ssl_new(BIO *bi)
  {
      BIO_SSL *bs = OPENSSL_zalloc(sizeof(*bs));
  
      if (bs == NULL) {
          BIOerr(BIO_F_SSL_NEW, ERR_R_MALLOC_FAILURE);
          return (0);
      }
      bi->init = 0;
      bi->ptr = (char *)bs;
      bi->flags = 0;
      return (1);
  }
  
  static int ssl_free(BIO *a)
  {
      BIO_SSL *bs;
  
      if (a == NULL)
          return (0);
      bs = (BIO_SSL *)a->ptr;
      if (bs->ssl != NULL)
          SSL_shutdown(bs->ssl);
      if (a->shutdown) {
          if (a->init)
              SSL_free(bs->ssl);
          a->init = 0;
          a->flags = 0;
      }
      OPENSSL_free(a->ptr);
      return (1);
  }
  
  static int ssl_read(BIO *b, char *out, int outl)
  {
      int ret = 1;
      BIO_SSL *sb;
      SSL *ssl;
      int retry_reason = 0;
      int r = 0;
  
      if (out == NULL)
          return (0);
      sb = (BIO_SSL *)b->ptr;
      ssl = sb->ssl;
  
      BIO_clear_retry_flags(b);
  
      ret = SSL_read(ssl, out, outl);
  
      switch (SSL_get_error(ssl, ret)) {
      case SSL_ERROR_NONE:
          if (ret <= 0)
              break;
          if (sb->renegotiate_count > 0) {
              sb->byte_count += ret;
              if (sb->byte_count > sb->renegotiate_count) {
                  sb->byte_count = 0;
                  sb->num_renegotiates++;
                  SSL_renegotiate(ssl);
                  r = 1;
              }
          }
          if ((sb->renegotiate_timeout > 0) && (!r)) {
              unsigned long tm;
  
              tm = (unsigned long)time(NULL);
              if (tm > sb->last_time + sb->renegotiate_timeout) {
                  sb->last_time = tm;
                  sb->num_renegotiates++;
                  SSL_renegotiate(ssl);
              }
          }
  
          break;
      case SSL_ERROR_WANT_READ:
          BIO_set_retry_read(b);
          break;
      case SSL_ERROR_WANT_WRITE:
          BIO_set_retry_write(b);
          break;
      case SSL_ERROR_WANT_X509_LOOKUP:
          BIO_set_retry_special(b);
          retry_reason = BIO_RR_SSL_X509_LOOKUP;
          break;
      case SSL_ERROR_WANT_ACCEPT:
          BIO_set_retry_special(b);
          retry_reason = BIO_RR_ACCEPT;
          break;
      case SSL_ERROR_WANT_CONNECT:
          BIO_set_retry_special(b);
          retry_reason = BIO_RR_CONNECT;
          break;
      case SSL_ERROR_SYSCALL:
      case SSL_ERROR_SSL:
      case SSL_ERROR_ZERO_RETURN:
      default:
          break;
      }
  
      b->retry_reason = retry_reason;
      return (ret);
  }
  
  static int ssl_write(BIO *b, const char *out, int outl)
  {
      int ret, r = 0;
      int retry_reason = 0;
      SSL *ssl;
      BIO_SSL *bs;
  
      if (out == NULL)
          return (0);
      bs = (BIO_SSL *)b->ptr;
      ssl = bs->ssl;
  
      BIO_clear_retry_flags(b);
  
      /*
       * ret=SSL_do_handshake(ssl); if (ret > 0)
       */
      ret = SSL_write(ssl, out, outl);
  
      switch (SSL_get_error(ssl, ret)) {
      case SSL_ERROR_NONE:
          if (ret <= 0)
              break;
          if (bs->renegotiate_count > 0) {
              bs->byte_count += ret;
              if (bs->byte_count > bs->renegotiate_count) {
                  bs->byte_count = 0;
                  bs->num_renegotiates++;
                  SSL_renegotiate(ssl);
                  r = 1;
              }
          }
          if ((bs->renegotiate_timeout > 0) && (!r)) {
              unsigned long tm;
  
              tm = (unsigned long)time(NULL);
              if (tm > bs->last_time + bs->renegotiate_timeout) {
                  bs->last_time = tm;
                  bs->num_renegotiates++;
                  SSL_renegotiate(ssl);
              }
          }
          break;
      case SSL_ERROR_WANT_WRITE:
          BIO_set_retry_write(b);
          break;
      case SSL_ERROR_WANT_READ:
          BIO_set_retry_read(b);
          break;
      case SSL_ERROR_WANT_X509_LOOKUP:
          BIO_set_retry_special(b);
          retry_reason = BIO_RR_SSL_X509_LOOKUP;
          break;
      case SSL_ERROR_WANT_CONNECT:
          BIO_set_retry_special(b);
          retry_reason = BIO_RR_CONNECT;
      case SSL_ERROR_SYSCALL:
      case SSL_ERROR_SSL:
      default:
          break;
      }
  
      b->retry_reason = retry_reason;
      return (ret);
  }
  
  static long ssl_ctrl(BIO *b, int cmd, long num, void *ptr)
  {
      SSL **sslp, *ssl;
      BIO_SSL *bs;
      BIO *dbio, *bio;
      long ret = 1;
  
      bs = (BIO_SSL *)b->ptr;
      ssl = bs->ssl;
      if ((ssl == NULL) && (cmd != BIO_C_SET_SSL))
          return (0);
      switch (cmd) {
      case BIO_CTRL_RESET:
          SSL_shutdown(ssl);
  
          if (ssl->handshake_func == ssl->method->ssl_connect)
              SSL_set_connect_state(ssl);
          else if (ssl->handshake_func == ssl->method->ssl_accept)
              SSL_set_accept_state(ssl);
  
          if (!SSL_clear(ssl)) {
              ret = 0;
              break;
          }
  
          if (b->next_bio != NULL)
              ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
          else if (ssl->rbio != NULL)
              ret = BIO_ctrl(ssl->rbio, cmd, num, ptr);
          else
              ret = 1;
          break;
      case BIO_CTRL_INFO:
          ret = 0;
          break;
      case BIO_C_SSL_MODE:
          if (num)                /* client mode */
              SSL_set_connect_state(ssl);
          else
              SSL_set_accept_state(ssl);
          break;
      case BIO_C_SET_SSL_RENEGOTIATE_TIMEOUT:
          ret = bs->renegotiate_timeout;
          if (num < 60)
              num = 5;
          bs->renegotiate_timeout = (unsigned long)num;
          bs->last_time = (unsigned long)time(NULL);
          break;
      case BIO_C_SET_SSL_RENEGOTIATE_BYTES:
          ret = bs->renegotiate_count;
          if ((long)num >= 512)
              bs->renegotiate_count = (unsigned long)num;
          break;
      case BIO_C_GET_SSL_NUM_RENEGOTIATES:
          ret = bs->num_renegotiates;
          break;
      case BIO_C_SET_SSL:
          if (ssl != NULL) {
              ssl_free(b);
              if (!ssl_new(b))
                  return 0;
          }
          b->shutdown = (int)num;
          ssl = (SSL *)ptr;
          ((BIO_SSL *)b->ptr)->ssl = ssl;
          bio = SSL_get_rbio(ssl);
          if (bio != NULL) {
              if (b->next_bio != NULL)
                  BIO_push(bio, b->next_bio);
              b->next_bio = bio;
              CRYPTO_add(&bio->references, 1, CRYPTO_LOCK_BIO);
          }
          b->init = 1;
          break;
      case BIO_C_GET_SSL:
          if (ptr != NULL) {
              sslp = (SSL **)ptr;
              *sslp = ssl;
          } else
              ret = 0;
          break;
      case BIO_CTRL_GET_CLOSE:
          ret = b->shutdown;
          break;
      case BIO_CTRL_SET_CLOSE:
          b->shutdown = (int)num;
          break;
      case BIO_CTRL_WPENDING:
          ret = BIO_ctrl(ssl->wbio, cmd, num, ptr);
          break;
      case BIO_CTRL_PENDING:
          ret = SSL_pending(ssl);
          if (ret == 0)
              ret = BIO_pending(ssl->rbio);
          break;
      case BIO_CTRL_FLUSH:
          BIO_clear_retry_flags(b);
          ret = BIO_ctrl(ssl->wbio, cmd, num, ptr);
          BIO_copy_next_retry(b);
          break;
      case BIO_CTRL_PUSH:
          if ((b->next_bio != NULL) && (b->next_bio != ssl->rbio)) {
              SSL_set_bio(ssl, b->next_bio, b->next_bio);
              CRYPTO_add(&b->next_bio->references, 1, CRYPTO_LOCK_BIO);
          }
          break;
      case BIO_CTRL_POP:
          /* Only detach if we are the BIO explicitly being popped */
          if (b == ptr) {
              /*
               * Shouldn't happen in practice because the rbio and wbio are the
               * same when pushed.
               */
              if (ssl->rbio != ssl->wbio)
                  BIO_free_all(ssl->wbio);
              if (b->next_bio != NULL)
                  CRYPTO_add(&b->next_bio->references, -1, CRYPTO_LOCK_BIO);
              ssl->wbio = NULL;
              ssl->rbio = NULL;
          }
          break;
      case BIO_C_DO_STATE_MACHINE:
          BIO_clear_retry_flags(b);
  
          b->retry_reason = 0;
          ret = (int)SSL_do_handshake(ssl);
  
          switch (SSL_get_error(ssl, (int)ret)) {
          case SSL_ERROR_WANT_READ:
              BIO_set_flags(b, BIO_FLAGS_READ | BIO_FLAGS_SHOULD_RETRY);
              break;
          case SSL_ERROR_WANT_WRITE:
              BIO_set_flags(b, BIO_FLAGS_WRITE | BIO_FLAGS_SHOULD_RETRY);
              break;
          case SSL_ERROR_WANT_CONNECT:
              BIO_set_flags(b, BIO_FLAGS_IO_SPECIAL | BIO_FLAGS_SHOULD_RETRY);
              b->retry_reason = b->next_bio->retry_reason;
              break;
          case SSL_ERROR_WANT_X509_LOOKUP:
              BIO_set_retry_special(b);
              b->retry_reason = BIO_RR_SSL_X509_LOOKUP;
              break;
          default:
              break;
          }
          break;
      case BIO_CTRL_DUP:
          dbio = (BIO *)ptr;
          SSL_free(((BIO_SSL *)dbio->ptr)->ssl);
          ((BIO_SSL *)dbio->ptr)->ssl = SSL_dup(ssl);
          ((BIO_SSL *)dbio->ptr)->renegotiate_count =
              ((BIO_SSL *)b->ptr)->renegotiate_count;
          ((BIO_SSL *)dbio->ptr)->byte_count = ((BIO_SSL *)b->ptr)->byte_count;
          ((BIO_SSL *)dbio->ptr)->renegotiate_timeout =
              ((BIO_SSL *)b->ptr)->renegotiate_timeout;
          ((BIO_SSL *)dbio->ptr)->last_time = ((BIO_SSL *)b->ptr)->last_time;
          ret = (((BIO_SSL *)dbio->ptr)->ssl != NULL);
          break;
      case BIO_C_GET_FD:
          ret = BIO_ctrl(ssl->rbio, cmd, num, ptr);
          break;
      case BIO_CTRL_SET_CALLBACK:
          {
  #if 0                           /* FIXME: Should this be used? -- Richard
                                   * Levitte */
              SSLerr(SSL_F_SSL_CTRL, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
              ret = -1;
  #else
              ret = 0;
  #endif
          }
          break;
      case BIO_CTRL_GET_CALLBACK:
          {
              void (**fptr) (const SSL *xssl, int type, int val);
  
              fptr = (void (**)(const SSL *xssl, int type, int val))ptr;
              *fptr = SSL_get_info_callback(ssl);
          }
          break;
      default:
          ret = BIO_ctrl(ssl->rbio, cmd, num, ptr);
          break;
      }
      return (ret);
  }
  
  static long ssl_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)
  {
      SSL *ssl;
      BIO_SSL *bs;
      long ret = 1;
  
      bs = (BIO_SSL *)b->ptr;
      ssl = bs->ssl;
      switch (cmd) {
      case BIO_CTRL_SET_CALLBACK:
          {
              /*
               * FIXME: setting this via a completely different prototype seems
               * like a crap idea
               */
              SSL_set_info_callback(ssl, (void (*)(const SSL *, int, int))fp);
          }
          break;
      default:
          ret = BIO_callback_ctrl(ssl->rbio, cmd, fp);
          break;
      }
      return (ret);
  }
  
  static int ssl_puts(BIO *bp, const char *str)
  {
      int n, ret;
  
      n = strlen(str);
      ret = BIO_write(bp, str, n);
      return (ret);
  }
  
  BIO *BIO_new_buffer_ssl_connect(SSL_CTX *ctx)
  {
  #ifndef OPENSSL_NO_SOCK
      BIO *ret = NULL, *buf = NULL, *ssl = NULL;
  
      if ((buf = BIO_new(BIO_f_buffer())) == NULL)
          return (NULL);
      if ((ssl = BIO_new_ssl_connect(ctx)) == NULL)
          goto err;
      if ((ret = BIO_push(buf, ssl)) == NULL)
          goto err;
      return (ret);
   err:
      BIO_free(buf);
      BIO_free(ssl);
  #endif
      return (NULL);
  }
  
  BIO *BIO_new_ssl_connect(SSL_CTX *ctx)
  {
  #ifndef OPENSSL_NO_SOCK
      BIO *ret = NULL, *con = NULL, *ssl = NULL;
  
      if ((con = BIO_new(BIO_s_connect())) == NULL)
          return (NULL);
      if ((ssl = BIO_new_ssl(ctx, 1)) == NULL)
          goto err;
      if ((ret = BIO_push(ssl, con)) == NULL)
          goto err;
      return (ret);
   err:
      BIO_free(con);
  #endif
      return (NULL);
  }
  
  BIO *BIO_new_ssl(SSL_CTX *ctx, int client)
  {
      BIO *ret;
      SSL *ssl;
  
      if ((ret = BIO_new(BIO_f_ssl())) == NULL)
          return (NULL);
      if ((ssl = SSL_new(ctx)) == NULL) {
          BIO_free(ret);
          return (NULL);
      }
      if (client)
          SSL_set_connect_state(ssl);
      else
          SSL_set_accept_state(ssl);
  
      BIO_set_ssl(ret, ssl, BIO_CLOSE);
      return (ret);
  }
  
  int BIO_ssl_copy_session_id(BIO *t, BIO *f)
  {
      t = BIO_find_type(t, BIO_TYPE_SSL);
      f = BIO_find_type(f, BIO_TYPE_SSL);
      if ((t == NULL) || (f == NULL))
          return (0);
      if ((((BIO_SSL *)t->ptr)->ssl == NULL) ||
          (((BIO_SSL *)f->ptr)->ssl == NULL))
          return (0);
      if (!SSL_copy_session_id(((BIO_SSL *)t->ptr)->ssl, ((BIO_SSL *)f->ptr)->ssl))
          return 0;
      return (1);
  }
  
  void BIO_ssl_shutdown(BIO *b)
  {
      SSL *s;
  
      while (b != NULL) {
          if (b->method->type == BIO_TYPE_SSL) {
              s = ((BIO_SSL *)b->ptr)->ssl;
              SSL_shutdown(s);
              break;
          }
          b = b->next_bio;
      }
  }
  