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BIO_s_connect(3)


NAME

  BIO_s_connect, BIO_set_conn_hostname, BIO_set_conn_port, BIO_set_conn_ip,
  BIO_set_conn_int_port, BIO_get_conn_hostname, BIO_get_conn_port,
  BIO_get_conn_ip, BIO_get_conn_int_port, BIO_set_nbio, BIO_do_connect -
  Connect BIO


SYNOPSIS

  #include <openssl/bio.h>

  BIO_METHOD * BIO_s_connect(
	  void );

       #define BIO_set_conn_hostname(b,name) BIO_ctrl(b,BIO_C_SET_CONNECT,0,(char *)name)
       #define BIO_set_conn_port(b,port) BIO_ctrl(b,BIO_C_SET_CONNECT,1,(char *)port)
       #define BIO_set_conn_ip(b,ip)	 BIO_ctrl(b,BIO_C_SET_CONNECT,2,(char *)ip)
       #define BIO_set_conn_int_port(b,port) BIO_ctrl(b,BIO_C_SET_CONNECT,3,(char *)port)
       #define BIO_get_conn_hostname(b)	 BIO_ptr_ctrl(b,BIO_C_GET_CONNECT,0)
       #define BIO_get_conn_port(b)	 BIO_ptr_ctrl(b,BIO_C_GET_CONNECT,1)
       #define BIO_get_conn_ip(b,ip) BIO_ptr_ctrl(b,BIO_C_SET_CONNECT,2)
       #define BIO_get_conn_int_port(b,port) BIO_int_ctrl(b,BIO_C_SET_CONNECT,3,port)

       #define BIO_set_nbio(b,n)       BIO_ctrl(b,BIO_C_SET_NBIO,(n),NULL)

       #define BIO_do_connect(b)       BIO_do_handshake(b)


DESCRIPTION

  The BIO_s_connect() function returns the connect BIO method. This is a
  wrapper round the platform's TCP/IP socket connection routines.

  Using connect BIOs TCP/IP connections can be made and data transferred
  using only BIO routines. In this way any platform specific operations are
  hidden by the BIO abstraction.

  Read and write operations on a connect BIO will perform I/O on the
  underlying connection. If no connection is established and the port and
  hostname is set up properly then a connection is established first.

  Connect BIOs support BIO_puts() but not BIO_gets().

  If the close flag is set on a connect BIO then any active connection is
  shutdown and the socket closed when the BIO is freed.

  Calling BIO_reset() on a connect BIO will close any active connection and
  reset the BIO into a state where it can connect to the same host again.

  The BIO_get_fd() function places the underlying socket in c if it is not
  NULL. It also returns the socket . If c is not NULL it should be of type
  (int *).

  BIO_set_conn_hostname() uses the string name to set the hostname. The
  hostname can be an IP address. The hostname can also include the port in
  the form hostname:port.  It is also acceptable to use the form
  hostname/any/other/path or hostname:port/any/other/path.

  The BIO_set_conn_port() function sets the port to port. The port can be the
  numerical form or a string such as http. A string will be looked up first
  using getservbyname() on the host platform, but if that fails a standard
  table of port names will be used. Currently the list is http, telnet,
  socks, https, ssl, ftp, gopher and wais.

  The BIO_set_conn_ip() function sets the IP address to ip using binary form,
  that is four bytes specifying the IP address in big-endian form.

  The BIO_set_conn_int_port() function sets the port using port. The port
  should be of type (int *).

  The BIO_get_conn_hostname() function returns the hostname of the connect
  BIO or NULL if the BIO is initialized but no hostname is set. This return
  value is an internal pointer which should not be modified.

  The BIO_get_conn_port() functon returns the port as a string.

  The BIO_get_conn_ip() function returns the IP address in binary form.

  The BIO_get_conn_int_port() function returns the port as an int.

  The BIO_set_nbio() function sets the non blocking I/O flag to n. If n is
  zero then blocking I/O is set. If n is 1 then non blocking I/O is set.
  Blocking I/O is the default. The call to BIO_set_nbio() should be made
  before the connection is established because	nonblocking I/O is set during
  the connect process.

  The BIO_do_connect() function attempts to connect the supplied BIO. It
  returns 1 if the connection was established successfully.  A zero or
  negative value is returned if the connection could not be established.  The
  BIO_should_retry() function should be used for nonblocking connect BIOs to
  determine if the call should be retried.


NOTES

  If blocking I/O is set, then a nonpositive return value from any I/O call
  is caused by an error condition. A zero return will normally mean that the
  connection was closed.

  If the port name is supplied as part of the host name then this will
  override any value set with BIO_set_conn_port(). This might be undesirable
  if the application does not wish to allow connection to arbitrary ports.
  This can be avoided by checking for the presence of the colon (:) character
  in the passed hostname, and either indicating an error or truncating the
  string at that point.

  The values returned by BIO_get_conn_hostname(), BIO_get_conn_port(),
  BIO_get_conn_ip(), and BIO_get_conn_int_port() are updated when a
  connection attempt is made. Before any connection attempt the values
  returned are those set by the application itself.

  Applications do not have to call BIO_do_connect() but may wish to do so to
  separate the connection process from other I/O processing.

  If nonblocking I/O is set then retries will be requested as appropriate.

  It addition to BIO_should_read() and BIO_should_write() it is also possible
  for BIO_should_io_special() to be true during the initial connection
  process with the reason BIO_RR_CONNECT.  If this is returned then this is
  an indication that a connection attempt would block. The application should
  then take appropriate action to wait until the underlying socket has
  connected and retry the call.


RETURN VALUES

  BIO_s_connect() returns the connect BIO method.

  BIO_get_fd() returns the socket or -1 if the BIO has not been initialized.

  BIO_set_conn_hostname(), BIO_set_conn_port(), BIO_set_conn_ip(), and
  BIO_set_conn_int_port() always return 1.

  BIO_get_conn_hostname() returns the connected hostname or NULL is none was
  set.

  BIO_get_conn_port() returns a string representing the connected port or
  NULL if not set.

  BIO_get_conn_ip() returns a pointer to the connected IP address in binary
  form or all zeros if not set.

  BIO_get_conn_int_port() returns the connected port or 0 if none was set.

  BIO_set_nbio() always returns 1.

  BIO_do_connect() returns 1 if the connection was successfully established
  and 0 or -1 if the connection failed.


EXAMPLES

  This example connects to a webserver on the local host and attempts to
  retrieve a page and copy the result to standard output.

       BIO *cbio, *out;
       int len;
       char tmpbuf[1024];
       ERR_load_crypto_strings();
       cbio = BIO_new_connect("localhost:http");
       out = BIO_new_fp(stdout, BIO_NOCLOSE);
		       if(BIO_do_connect(cbio) <= 0) {fprintf(stderr, "Error connecting to server\n");
		       ERR_print_errors_fp(stderr);
		       /* whatever ... */
		       }
       BIO_puts(cbio, "GET / HTTP/1.0\n\n");
       for(;;) {
		       len = BIO_read(cbio, tmpbuf, 1024);
		       if(len <= 0) break;
		       BIO_write(out, tmpbuf, len);
       }
       BIO_free(cbio);
       BIO_free(out);


SEE ALSO

  TBA

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