crypto/bio/connect.c - boringssl - Git at Google

 /* 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 <openssl/bio.h>

 #if !defined(OPENSSL_NO_SOCK)

 #include <assert.h>
 #include <errno.h>
 #include <string.h>

 #if !defined(OPENSSL_WINDOWS)
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <unistd.h>
 #else
 OPENSSL_MSVC_PRAGMA(warning(push, 3))
 #include <winsock2.h>
 #include <ws2tcpip.h>
 OPENSSL_MSVC_PRAGMA(warning(pop))
 #endif

 #include <openssl/err.h>
 #include <openssl/mem.h>

 #include "internal.h"
 #include "../internal.h"


 enum {
   BIO_CONN_S_BEFORE,
   BIO_CONN_S_BLOCKED_CONNECT,
   BIO_CONN_S_OK,
 };

 typedef struct bio_connect_st {
   int state;

   char *param_hostname;
   char *param_port;
   int nbio;

   unsigned short port;

   struct sockaddr_storage them;
   socklen_t them_length;

   // the file descriptor is kept in bio->num in order to match the socket
   // BIO.

   // info_callback is called when the connection is initially made
   // callback(BIO,state,ret);  The callback should return 'ret', state is for
   // compatibility with the SSL info_callback.
   int (*info_callback)(const BIO *bio, int state, int ret);
 } BIO_CONNECT;

 #if !defined(OPENSSL_WINDOWS)
 static int closesocket(int sock) {
   return close(sock);
 }
 #endif

 // split_host_and_port sets |*out_host| and |*out_port| to the host and port
 // parsed from |name|. It returns one on success or zero on error. Even when
 // successful, |*out_port| may be NULL on return if no port was specified.
 static int split_host_and_port(char **out_host, char **out_port,
                                const char *name) {
   const char *host, *port = NULL;
   size_t host_len = 0;

   *out_host = NULL;
   *out_port = NULL;

   if (name[0] == '[') {  // bracketed IPv6 address
     const char *close = strchr(name, ']');
     if (close == NULL) {
       return 0;
     }
     host = name + 1;
     host_len = close - host;
     if (close[1] == ':') {  // [IP]:port
       port = close + 2;
     } else if (close[1] != 0) {
       return 0;
     }
   } else {
     const char *colon = strchr(name, ':');
     if (colon == NULL || strchr(colon + 1, ':') != NULL) {  // IPv6 address
       host = name;
       host_len = strlen(name);
     } else {  // host:port
       host = name;
       host_len = colon - name;
       port = colon + 1;
     }
   }

   *out_host = OPENSSL_strndup(host, host_len);
   if (*out_host == NULL) {
     return 0;
   }
   if (port == NULL) {
     *out_port = NULL;
     return 1;
   }
   *out_port = OPENSSL_strdup(port);
   if (*out_port == NULL) {
     OPENSSL_free(*out_host);
     *out_host = NULL;
     return 0;
   }
   return 1;
 }

 static int conn_state(BIO *bio, BIO_CONNECT *c) {
   int ret = -1, i;
   int (*cb)(const BIO *, int, int) = NULL;

   if (c->info_callback != NULL) {
     cb = c->info_callback;
   }

   for (;;) {
     switch (c->state) {
       case BIO_CONN_S_BEFORE:
         // If there's a hostname and a port, assume that both are
         // exactly what they say. If there is only a hostname, try
         // (just once) to split it into a hostname and port.

         if (c->param_hostname == NULL) {
           OPENSSL_PUT_ERROR(BIO, BIO_R_NO_HOSTNAME_SPECIFIED);
           goto exit_loop;
         }

         if (c->param_port == NULL) {
           char *host, *port;
           if (!split_host_and_port(&host, &port, c->param_hostname) ||
               port == NULL) {
             OPENSSL_free(host);
             OPENSSL_free(port);
             OPENSSL_PUT_ERROR(BIO, BIO_R_NO_PORT_SPECIFIED);
             ERR_add_error_data(2, "host=", c->param_hostname);
             goto exit_loop;
           }

           OPENSSL_free(c->param_port);
           c->param_port = port;
           OPENSSL_free(c->param_hostname);
           c->param_hostname = host;
         }

         if (!bio_ip_and_port_to_socket_and_addr(
                 &bio->num, &c->them, &c->them_length, c->param_hostname,
                 c->param_port)) {
           OPENSSL_PUT_ERROR(BIO, BIO_R_UNABLE_TO_CREATE_SOCKET);
           ERR_add_error_data(4, "host=", c->param_hostname, ":", c->param_port);
           goto exit_loop;
         }

         if (c->nbio) {
           if (!bio_socket_nbio(bio->num, 1)) {
             OPENSSL_PUT_ERROR(BIO, BIO_R_ERROR_SETTING_NBIO);
             ERR_add_error_data(4, "host=", c->param_hostname, ":",
                                c->param_port);
             goto exit_loop;
           }
         }

         i = 1;
         ret = setsockopt(bio->num, SOL_SOCKET, SO_KEEPALIVE, (char *)&i,
                          sizeof(i));
         if (ret < 0) {
           OPENSSL_PUT_SYSTEM_ERROR();
           OPENSSL_PUT_ERROR(BIO, BIO_R_KEEPALIVE);
           ERR_add_error_data(4, "host=", c->param_hostname, ":", c->param_port);
           goto exit_loop;
         }

         BIO_clear_retry_flags(bio);
         ret = connect(bio->num, (struct sockaddr*) &c->them, c->them_length);
         if (ret < 0) {
           if (bio_socket_should_retry(ret)) {
             BIO_set_flags(bio, (BIO_FLAGS_IO_SPECIAL | BIO_FLAGS_SHOULD_RETRY));
             c->state = BIO_CONN_S_BLOCKED_CONNECT;
             bio->retry_reason = BIO_RR_CONNECT;
           } else {
             OPENSSL_PUT_SYSTEM_ERROR();
             OPENSSL_PUT_ERROR(BIO, BIO_R_CONNECT_ERROR);
             ERR_add_error_data(4, "host=", c->param_hostname, ":",
                                c->param_port);
           }
           goto exit_loop;
         } else {
           c->state = BIO_CONN_S_OK;
         }
         break;

       case BIO_CONN_S_BLOCKED_CONNECT:
         i = bio_sock_error(bio->num);
         if (i) {
           if (bio_socket_should_retry(ret)) {
             BIO_set_flags(bio, (BIO_FLAGS_IO_SPECIAL | BIO_FLAGS_SHOULD_RETRY));
             c->state = BIO_CONN_S_BLOCKED_CONNECT;
             bio->retry_reason = BIO_RR_CONNECT;
             ret = -1;
           } else {
             BIO_clear_retry_flags(bio);
             OPENSSL_PUT_SYSTEM_ERROR();
             OPENSSL_PUT_ERROR(BIO, BIO_R_NBIO_CONNECT_ERROR);
             ERR_add_error_data(4, "host=", c->param_hostname, ":", c->param_port);
             ret = 0;
           }
           goto exit_loop;
         } else {
           c->state = BIO_CONN_S_OK;
         }
         break;

       case BIO_CONN_S_OK:
         ret = 1;
         goto exit_loop;
       default:
         assert(0);
         goto exit_loop;
     }

     if (cb != NULL) {
       ret = cb((BIO *)bio, c->state, ret);
       if (ret == 0) {
         goto end;
       }
     }
   }

 exit_loop:
   if (cb != NULL) {
     ret = cb((BIO *)bio, c->state, ret);
   }

 end:
   return ret;
 }

 static BIO_CONNECT *BIO_CONNECT_new(void) {
   BIO_CONNECT *ret = OPENSSL_zalloc(sizeof(BIO_CONNECT));
   if (ret == NULL) {
     return NULL;
   }
   ret->state = BIO_CONN_S_BEFORE;
   return ret;
 }

 static void BIO_CONNECT_free(BIO_CONNECT *c) {
   if (c == NULL) {
     return;
   }

   OPENSSL_free(c->param_hostname);
   OPENSSL_free(c->param_port);
   OPENSSL_free(c);
 }

 static int conn_new(BIO *bio) {
   bio->init = 0;
   bio->num = -1;
   bio->flags = 0;
   bio->ptr = BIO_CONNECT_new();
   return bio->ptr != NULL;
 }

 static void conn_close_socket(BIO *bio) {
   BIO_CONNECT *c = (BIO_CONNECT *) bio->ptr;

   if (bio->num == -1) {
     return;
   }

   // Only do a shutdown if things were established
   if (c->state == BIO_CONN_S_OK) {
     shutdown(bio->num, 2);
   }
   closesocket(bio->num);
   bio->num = -1;
 }

 static int conn_free(BIO *bio) {
   if (bio->shutdown) {
     conn_close_socket(bio);
   }

   BIO_CONNECT_free((BIO_CONNECT*) bio->ptr);

   return 1;
 }

 static int conn_read(BIO *bio, char *out, int out_len) {
   int ret = 0;
   BIO_CONNECT *data;

   data = (BIO_CONNECT *)bio->ptr;
   if (data->state != BIO_CONN_S_OK) {
     ret = conn_state(bio, data);
     if (ret <= 0) {
       return ret;
     }
   }

   bio_clear_socket_error();
   ret = (int)recv(bio->num, out, out_len, 0);
   BIO_clear_retry_flags(bio);
   if (ret <= 0) {
     if (bio_socket_should_retry(ret)) {
       BIO_set_retry_read(bio);
     }
   }

   return ret;
 }

 static int conn_write(BIO *bio, const char *in, int in_len) {
   int ret;
   BIO_CONNECT *data;

   data = (BIO_CONNECT *)bio->ptr;
   if (data->state != BIO_CONN_S_OK) {
     ret = conn_state(bio, data);
     if (ret <= 0) {
       return ret;
     }
   }

   bio_clear_socket_error();
   ret = (int)send(bio->num, in, in_len, 0);
   BIO_clear_retry_flags(bio);
   if (ret <= 0) {
     if (bio_socket_should_retry(ret)) {
       BIO_set_retry_write(bio);
     }
   }

   return ret;
 }

 static long conn_ctrl(BIO *bio, int cmd, long num, void *ptr) {
   int *ip;
   long ret = 1;
   BIO_CONNECT *data;

   data = (BIO_CONNECT *)bio->ptr;

   switch (cmd) {
     case BIO_CTRL_RESET:
       ret = 0;
       data->state = BIO_CONN_S_BEFORE;
       conn_close_socket(bio);
       bio->flags = 0;
       break;
     case BIO_C_DO_STATE_MACHINE:
       // use this one to start the connection
       if (data->state != BIO_CONN_S_OK) {
         ret = (long)conn_state(bio, data);
       } else {
         ret = 1;
       }
       break;
     case BIO_C_SET_CONNECT:
       if (ptr != NULL) {
         bio->init = 1;
         if (num == 0) {
           OPENSSL_free(data->param_hostname);
           data->param_hostname = OPENSSL_strdup(ptr);
           if (data->param_hostname == NULL) {
             ret = 0;
           }
         } else if (num == 1) {
           OPENSSL_free(data->param_port);
           data->param_port = OPENSSL_strdup(ptr);
           if (data->param_port == NULL) {
             ret = 0;
           }
         } else {
           ret = 0;
         }
       }
       break;
     case BIO_C_SET_NBIO:
       data->nbio = (int)num;
       break;
     case BIO_C_GET_FD:
       if (bio->init) {
         ip = (int *)ptr;
         if (ip != NULL) {
           *ip = bio->num;
         }
         ret = bio->num;
       } else {
         ret = -1;
       }
       break;
     case BIO_CTRL_GET_CLOSE:
       ret = bio->shutdown;
       break;
     case BIO_CTRL_SET_CLOSE:
       bio->shutdown = (int)num;
       break;
     case BIO_CTRL_PENDING:
     case BIO_CTRL_WPENDING:
       ret = 0;
       break;
     case BIO_CTRL_FLUSH:
       break;
     case BIO_CTRL_GET_CALLBACK: {
       int (**fptr)(const BIO *bio, int state, int xret) = ptr;
       *fptr = data->info_callback;
     } break;
     default:
       ret = 0;
       break;
   }
   return ret;
 }

 static long conn_callback_ctrl(BIO *bio, int cmd, bio_info_cb fp) {
   long ret = 1;
   BIO_CONNECT *data;

   data = (BIO_CONNECT *)bio->ptr;

   switch (cmd) {
     case BIO_CTRL_SET_CALLBACK:
       // This is the actual type signature of |fp|. The caller is expected to
       // cast it to |bio_info_cb| due to the |BIO_callback_ctrl| calling
       // convention.
       OPENSSL_MSVC_PRAGMA(warning(push))
       OPENSSL_MSVC_PRAGMA(warning(disable : 4191))
       OPENSSL_CLANG_PRAGMA("clang diagnostic push")
       OPENSSL_CLANG_PRAGMA("clang diagnostic ignored \"-Wunknown-warning-option\"")
       OPENSSL_CLANG_PRAGMA("clang diagnostic ignored \"-Wcast-function-type\"")
       data->info_callback = (int (*)(const struct bio_st *, int, int))fp;
       OPENSSL_CLANG_PRAGMA("clang diagnostic pop")
       OPENSSL_MSVC_PRAGMA(warning(pop))
       break;
     default:
       ret = 0;
       break;
   }
   return ret;
 }

 BIO *BIO_new_connect(const char *hostname) {
   BIO *ret;

   ret = BIO_new(BIO_s_connect());
   if (ret == NULL) {
     return NULL;
   }
   if (!BIO_set_conn_hostname(ret, hostname)) {
     BIO_free(ret);
     return NULL;
   }
   return ret;
 }

 static const BIO_METHOD methods_connectp = {
     BIO_TYPE_CONNECT, "socket connect",   conn_write, conn_read,
     NULL /* puts */,  NULL /* gets */,    conn_ctrl,  conn_new,
     conn_free,        conn_callback_ctrl,
 };

 const BIO_METHOD *BIO_s_connect(void) { return &methods_connectp; }

 int BIO_set_conn_hostname(BIO *bio, const char *name) {
   return (int)BIO_ctrl(bio, BIO_C_SET_CONNECT, 0, (void*) name);
 }

 int BIO_set_conn_port(BIO *bio, const char *port_str) {
   return (int)BIO_ctrl(bio, BIO_C_SET_CONNECT, 1, (void*) port_str);
 }

 int BIO_set_conn_int_port(BIO *bio, const int *port) {
   char buf[DECIMAL_SIZE(int) + 1];
   snprintf(buf, sizeof(buf), "%d", *port);
   return BIO_set_conn_port(bio, buf);
 }

 int BIO_set_nbio(BIO *bio, int on) {
   return (int)BIO_ctrl(bio, BIO_C_SET_NBIO, on, NULL);
 }

 int BIO_do_connect(BIO *bio) {
   return (int)BIO_ctrl(bio, BIO_C_DO_STATE_MACHINE, 0, NULL);
 }

 #endif  // OPENSSL_NO_SOCK
	/* 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 <openssl/bio.h>

	#if !defined(OPENSSL_NO_SOCK)

	#include <assert.h>
	#include <errno.h>
	#include <string.h>

	#if !defined(OPENSSL_WINDOWS)
	#include <sys/socket.h>
	#include <netinet/in.h>
	#include <arpa/inet.h>
	#include <unistd.h>
	#else
	OPENSSL_MSVC_PRAGMA(warning(push, 3))
	#include <winsock2.h>
	#include <ws2tcpip.h>
	OPENSSL_MSVC_PRAGMA(warning(pop))
	#endif

	#include <openssl/err.h>
	#include <openssl/mem.h>

	#include "internal.h"
	#include "../internal.h"


	enum {
	BIO_CONN_S_BEFORE,
	BIO_CONN_S_BLOCKED_CONNECT,
	BIO_CONN_S_OK,
	};

	typedef struct bio_connect_st {
	int state;

	char *param_hostname;
	char *param_port;
	int nbio;

	unsigned short port;

	struct sockaddr_storage them;
	socklen_t them_length;

	// the file descriptor is kept in bio->num in order to match the socket
	// BIO.

	// info_callback is called when the connection is initially made
	// callback(BIO,state,ret); The callback should return 'ret', state is for
	// compatibility with the SSL info_callback.
	int (info_callback)(const BIO bio, int state, int ret);
	} BIO_CONNECT;

	#if !defined(OPENSSL_WINDOWS)
	static int closesocket(int sock) {
	return close(sock);
	}
	#endif

	// split_host_and_port sets \|out_host\| and \|out_port\| to the host and port
	// parsed from \|name\|. It returns one on success or zero on error. Even when
	// successful, \|*out_port\| may be NULL on return if no port was specified.
	static int split_host_and_port(char out_host, char out_port,
	const char *name) {
	const char host, port = NULL;
	size_t host_len = 0;

	*out_host = NULL;
	*out_port = NULL;

	if (name[0] == '[') { // bracketed IPv6 address
	const char *close = strchr(name, ']');
	if (close == NULL) {
	return 0;
	}
	host = name + 1;
	host_len = close - host;
	if (close[1] == ':') { // [IP]:port
	port = close + 2;
	} else if (close[1] != 0) {
	return 0;
	}
	} else {
	const char *colon = strchr(name, ':');
	if (colon == NULL \|\| strchr(colon + 1, ':') != NULL) { // IPv6 address
	host = name;
	host_len = strlen(name);
	} else { // host:port
	host = name;
	host_len = colon - name;
	port = colon + 1;
	}
	}

	*out_host = OPENSSL_strndup(host, host_len);
	if (*out_host == NULL) {
	return 0;
	}
	if (port == NULL) {
	*out_port = NULL;
	return 1;
	}
	*out_port = OPENSSL_strdup(port);
	if (*out_port == NULL) {
	OPENSSL_free(*out_host);
	*out_host = NULL;
	return 0;
	}
	return 1;
	}

	static int conn_state(BIO bio, BIO_CONNECT c) {
	int ret = -1, i;
	int (cb)(const BIO , int, int) = NULL;

	if (c->info_callback != NULL) {
	cb = c->info_callback;
	}

	for (;;) {
	switch (c->state) {
	case BIO_CONN_S_BEFORE:
	// If there's a hostname and a port, assume that both are
	// exactly what they say. If there is only a hostname, try
	// (just once) to split it into a hostname and port.

	if (c->param_hostname == NULL) {
	OPENSSL_PUT_ERROR(BIO, BIO_R_NO_HOSTNAME_SPECIFIED);
	goto exit_loop;
	}

	if (c->param_port == NULL) {
	char host, port;
	if (!split_host_and_port(&host, &port, c->param_hostname) \|\|
	port == NULL) {
	OPENSSL_free(host);
	OPENSSL_free(port);
	OPENSSL_PUT_ERROR(BIO, BIO_R_NO_PORT_SPECIFIED);
	ERR_add_error_data(2, "host=", c->param_hostname);
	goto exit_loop;
	}

	OPENSSL_free(c->param_port);
	c->param_port = port;
	OPENSSL_free(c->param_hostname);
	c->param_hostname = host;
	}

	if (!bio_ip_and_port_to_socket_and_addr(
	&bio->num, &c->them, &c->them_length, c->param_hostname,
	c->param_port)) {
	OPENSSL_PUT_ERROR(BIO, BIO_R_UNABLE_TO_CREATE_SOCKET);
	ERR_add_error_data(4, "host=", c->param_hostname, ":", c->param_port);
	goto exit_loop;
	}

	if (c->nbio) {
	if (!bio_socket_nbio(bio->num, 1)) {
	OPENSSL_PUT_ERROR(BIO, BIO_R_ERROR_SETTING_NBIO);
	ERR_add_error_data(4, "host=", c->param_hostname, ":",
	c->param_port);
	goto exit_loop;
	}
	}

	i = 1;
	ret = setsockopt(bio->num, SOL_SOCKET, SO_KEEPALIVE, (char *)&i,
	sizeof(i));
	if (ret < 0) {
	OPENSSL_PUT_SYSTEM_ERROR();
	OPENSSL_PUT_ERROR(BIO, BIO_R_KEEPALIVE);
	ERR_add_error_data(4, "host=", c->param_hostname, ":", c->param_port);
	goto exit_loop;
	}

	BIO_clear_retry_flags(bio);
	ret = connect(bio->num, (struct sockaddr*) &c->them, c->them_length);
	if (ret < 0) {
	if (bio_socket_should_retry(ret)) {
	BIO_set_flags(bio, (BIO_FLAGS_IO_SPECIAL \| BIO_FLAGS_SHOULD_RETRY));
	c->state = BIO_CONN_S_BLOCKED_CONNECT;
	bio->retry_reason = BIO_RR_CONNECT;
	} else {
	OPENSSL_PUT_SYSTEM_ERROR();
	OPENSSL_PUT_ERROR(BIO, BIO_R_CONNECT_ERROR);
	ERR_add_error_data(4, "host=", c->param_hostname, ":",
	c->param_port);
	}
	goto exit_loop;
	} else {
	c->state = BIO_CONN_S_OK;
	}
	break;

	case BIO_CONN_S_BLOCKED_CONNECT:
	i = bio_sock_error(bio->num);
	if (i) {
	if (bio_socket_should_retry(ret)) {
	BIO_set_flags(bio, (BIO_FLAGS_IO_SPECIAL \| BIO_FLAGS_SHOULD_RETRY));
	c->state = BIO_CONN_S_BLOCKED_CONNECT;
	bio->retry_reason = BIO_RR_CONNECT;
	ret = -1;
	} else {
	BIO_clear_retry_flags(bio);
	OPENSSL_PUT_SYSTEM_ERROR();
	OPENSSL_PUT_ERROR(BIO, BIO_R_NBIO_CONNECT_ERROR);
	ERR_add_error_data(4, "host=", c->param_hostname, ":", c->param_port);
	ret = 0;
	}
	goto exit_loop;
	} else {
	c->state = BIO_CONN_S_OK;
	}
	break;

	case BIO_CONN_S_OK:
	ret = 1;
	goto exit_loop;
	default:
	assert(0);
	goto exit_loop;
	}

	if (cb != NULL) {
	ret = cb((BIO *)bio, c->state, ret);
	if (ret == 0) {
	goto end;
	}
	}
	}

	exit_loop:
	if (cb != NULL) {
	ret = cb((BIO *)bio, c->state, ret);
	}

	end:
	return ret;
	}

	static BIO_CONNECT *BIO_CONNECT_new(void) {
	BIO_CONNECT *ret = OPENSSL_zalloc(sizeof(BIO_CONNECT));
	if (ret == NULL) {
	return NULL;
	}
	ret->state = BIO_CONN_S_BEFORE;
	return ret;
	}

	static void BIO_CONNECT_free(BIO_CONNECT *c) {
	if (c == NULL) {
	return;
	}

	OPENSSL_free(c->param_hostname);
	OPENSSL_free(c->param_port);
	OPENSSL_free(c);
	}

	static int conn_new(BIO *bio) {
	bio->init = 0;
	bio->num = -1;
	bio->flags = 0;
	bio->ptr = BIO_CONNECT_new();
	return bio->ptr != NULL;
	}

	static void conn_close_socket(BIO *bio) {
	BIO_CONNECT c = (BIO_CONNECT ) bio->ptr;

	if (bio->num == -1) {
	return;
	}

	// Only do a shutdown if things were established
	if (c->state == BIO_CONN_S_OK) {
	shutdown(bio->num, 2);
	}
	closesocket(bio->num);
	bio->num = -1;
	}

	static int conn_free(BIO *bio) {
	if (bio->shutdown) {
	conn_close_socket(bio);
	}

	BIO_CONNECT_free((BIO_CONNECT*) bio->ptr);

	return 1;
	}

	static int conn_read(BIO bio, char out, int out_len) {
	int ret = 0;
	BIO_CONNECT *data;

	data = (BIO_CONNECT *)bio->ptr;
	if (data->state != BIO_CONN_S_OK) {
	ret = conn_state(bio, data);
	if (ret <= 0) {
	return ret;
	}
	}

	bio_clear_socket_error();
	ret = (int)recv(bio->num, out, out_len, 0);
	BIO_clear_retry_flags(bio);
	if (ret <= 0) {
	if (bio_socket_should_retry(ret)) {
	BIO_set_retry_read(bio);
	}
	}

	return ret;
	}

	static int conn_write(BIO bio, const char in, int in_len) {
	int ret;
	BIO_CONNECT *data;

	data = (BIO_CONNECT *)bio->ptr;
	if (data->state != BIO_CONN_S_OK) {
	ret = conn_state(bio, data);
	if (ret <= 0) {
	return ret;
	}
	}

	bio_clear_socket_error();
	ret = (int)send(bio->num, in, in_len, 0);
	BIO_clear_retry_flags(bio);
	if (ret <= 0) {
	if (bio_socket_should_retry(ret)) {
	BIO_set_retry_write(bio);
	}
	}

	return ret;
	}

	static long conn_ctrl(BIO bio, int cmd, long num, void ptr) {
	int *ip;
	long ret = 1;
	BIO_CONNECT *data;

	data = (BIO_CONNECT *)bio->ptr;

	switch (cmd) {
	case BIO_CTRL_RESET:
	ret = 0;
	data->state = BIO_CONN_S_BEFORE;
	conn_close_socket(bio);
	bio->flags = 0;
	break;
	case BIO_C_DO_STATE_MACHINE:
	// use this one to start the connection
	if (data->state != BIO_CONN_S_OK) {
	ret = (long)conn_state(bio, data);
	} else {
	ret = 1;
	}
	break;
	case BIO_C_SET_CONNECT:
	if (ptr != NULL) {
	bio->init = 1;
	if (num == 0) {
	OPENSSL_free(data->param_hostname);
	data->param_hostname = OPENSSL_strdup(ptr);
	if (data->param_hostname == NULL) {
	ret = 0;
	}
	} else if (num == 1) {
	OPENSSL_free(data->param_port);
	data->param_port = OPENSSL_strdup(ptr);
	if (data->param_port == NULL) {
	ret = 0;
	}
	} else {
	ret = 0;
	}
	}
	break;
	case BIO_C_SET_NBIO:
	data->nbio = (int)num;
	break;
	case BIO_C_GET_FD:
	if (bio->init) {
	ip = (int *)ptr;
	if (ip != NULL) {
	*ip = bio->num;
	}
	ret = bio->num;
	} else {
	ret = -1;
	}
	break;
	case BIO_CTRL_GET_CLOSE:
	ret = bio->shutdown;
	break;
	case BIO_CTRL_SET_CLOSE:
	bio->shutdown = (int)num;
	break;
	case BIO_CTRL_PENDING:
	case BIO_CTRL_WPENDING:
	ret = 0;
	break;
	case BIO_CTRL_FLUSH:
	break;
	case BIO_CTRL_GET_CALLBACK: {
	int (*fptr)(const BIO bio, int state, int xret) = ptr;
	*fptr = data->info_callback;
	} break;
	default:
	ret = 0;
	break;
	}
	return ret;
	}

	static long conn_callback_ctrl(BIO *bio, int cmd, bio_info_cb fp) {
	long ret = 1;
	BIO_CONNECT *data;

	data = (BIO_CONNECT *)bio->ptr;

	switch (cmd) {
	case BIO_CTRL_SET_CALLBACK:
	// This is the actual type signature of \|fp\|. The caller is expected to
	// cast it to \|bio_info_cb\| due to the \|BIO_callback_ctrl\| calling
	// convention.
	OPENSSL_MSVC_PRAGMA(warning(push))
	OPENSSL_MSVC_PRAGMA(warning(disable : 4191))
	OPENSSL_CLANG_PRAGMA("clang diagnostic push")
	OPENSSL_CLANG_PRAGMA("clang diagnostic ignored \"-Wunknown-warning-option\"")
	OPENSSL_CLANG_PRAGMA("clang diagnostic ignored \"-Wcast-function-type\"")
	data->info_callback = (int ()(const struct bio_st , int, int))fp;
	OPENSSL_CLANG_PRAGMA("clang diagnostic pop")
	OPENSSL_MSVC_PRAGMA(warning(pop))
	break;
	default:
	ret = 0;
	break;
	}
	return ret;
	}

	BIO BIO_new_connect(const char hostname) {
	BIO *ret;

	ret = BIO_new(BIO_s_connect());
	if (ret == NULL) {
	return NULL;
	}
	if (!BIO_set_conn_hostname(ret, hostname)) {
	BIO_free(ret);
	return NULL;
	}
	return ret;
	}

	static const BIO_METHOD methods_connectp = {
	BIO_TYPE_CONNECT, "socket connect", conn_write, conn_read,
	NULL /* puts /, NULL / gets */, conn_ctrl, conn_new,
	conn_free, conn_callback_ctrl,
	};

	const BIO_METHOD *BIO_s_connect(void) { return &methods_connectp; }

	int BIO_set_conn_hostname(BIO bio, const char name) {
	return (int)BIO_ctrl(bio, BIO_C_SET_CONNECT, 0, (void*) name);
	}

	int BIO_set_conn_port(BIO bio, const char port_str) {
	return (int)BIO_ctrl(bio, BIO_C_SET_CONNECT, 1, (void*) port_str);
	}

	int BIO_set_conn_int_port(BIO bio, const int port) {
	char buf[DECIMAL_SIZE(int) + 1];
	snprintf(buf, sizeof(buf), "%d", *port);
	return BIO_set_conn_port(bio, buf);
	}

	int BIO_set_nbio(BIO *bio, int on) {
	return (int)BIO_ctrl(bio, BIO_C_SET_NBIO, on, NULL);
	}

	int BIO_do_connect(BIO *bio) {
	return (int)BIO_ctrl(bio, BIO_C_DO_STATE_MACHINE, 0, NULL);
	}

	#endif // OPENSSL_NO_SOCK