5 BIO_s_connect, BIO_new_connect, BIO_set_conn_hostname, BIO_set_conn_port,
6 BIO_set_conn_ip, BIO_set_conn_int_port, BIO_get_conn_hostname,
7 BIO_get_conn_port, BIO_get_conn_ip, BIO_get_conn_int_port,
8 BIO_set_nbio, BIO_do_connect - connect BIO
12 #include <openssl/bio.h>
14 const BIO_METHOD * BIO_s_connect(void);
16 BIO *BIO_new_connect(char *name);
18 long BIO_set_conn_hostname(BIO *b, char *name);
19 long BIO_set_conn_port(BIO *b, char *port);
20 long BIO_set_conn_address(BIO *b, BIO_ADDR *addr);
21 const char *BIO_get_conn_hostname(BIO *b);
22 const char *BIO_get_conn_port(BIO *b);
23 const BIO_ADDR *BIO_get_conn_address(BIO *b);
25 long BIO_set_nbio(BIO *b, long n);
27 int BIO_do_connect(BIO *b);
31 BIO_s_connect() returns the connect BIO method. This is a wrapper
32 round the platform's TCP/IP socket connection routines.
34 Using connect BIOs, TCP/IP connections can be made and data
35 transferred using only BIO routines. In this way any platform
36 specific operations are hidden by the BIO abstraction.
38 Read and write operations on a connect BIO will perform I/O
39 on the underlying connection. If no connection is established
40 and the port and hostname (see below) is set up properly then
41 a connection is established first.
43 Connect BIOs support BIO_puts() but not BIO_gets().
45 If the close flag is set on a connect BIO then any active
46 connection is shutdown and the socket closed when the BIO
49 Calling BIO_reset() on a connect BIO will close any active
50 connection and reset the BIO into a state where it can connect
51 to the same host again.
53 BIO_get_fd() places the underlying socket in B<c> if it is not NULL,
54 it also returns the socket . If B<c> is not NULL it should be of
57 BIO_set_conn_hostname() uses the string B<name> to set the hostname.
58 The hostname can be an IP address; if the address is an IPv6 one, it
59 must be enclosed with brackets. The hostname can also include the
60 port in the form hostname:port.
62 BIO_set_conn_port() sets the port to B<port>. B<port> can be the
63 numerical form or a string such as "http". A string will be looked
64 up first using getservbyname() on the host platform but if that
65 fails a standard table of port names will be used. This internal
66 list is http, telnet, socks, https, ssl, ftp, and gopher.
68 BIO_set_conn_address() sets the address and port information using
71 BIO_get_conn_hostname() returns the hostname of the connect BIO or
72 NULL if the BIO is initialized but no hostname is set.
73 This return value is an internal pointer which should not be modified.
75 BIO_get_conn_port() returns the port as a string.
76 This return value is an internal pointer which should not be modified.
78 BIO_get_conn_address() returns the address information as a BIO_ADDR.
79 This return value is an internal pointer which should not be modified.
81 BIO_set_nbio() sets the non blocking I/O flag to B<n>. If B<n> is
82 zero then blocking I/O is set. If B<n> is 1 then non blocking I/O
83 is set. Blocking I/O is the default. The call to BIO_set_nbio()
84 should be made before the connection is established because
85 non blocking I/O is set during the connect process.
87 BIO_new_connect() combines BIO_new() and BIO_set_conn_hostname() into
88 a single call: that is it creates a new connect BIO with B<name>.
90 BIO_do_connect() attempts to connect the supplied BIO. It returns 1
91 if the connection was established successfully. A zero or negative
92 value is returned if the connection could not be established, the
93 call BIO_should_retry() should be used for non blocking connect BIOs
94 to determine if the call should be retried.
98 If blocking I/O is set then a non positive return value from any
99 I/O call is caused by an error condition, although a zero return
100 will normally mean that the connection was closed.
102 If the port name is supplied as part of the host name then this will
103 override any value set with BIO_set_conn_port(). This may be undesirable
104 if the application does not wish to allow connection to arbitrary
105 ports. This can be avoided by checking for the presence of the ':'
106 character in the passed hostname and either indicating an error or
107 truncating the string at that point.
109 The values returned by BIO_get_conn_hostname(), BIO_get_conn_port(),
110 BIO_get_conn_ip() and BIO_get_conn_int_port() are updated when a
111 connection attempt is made. Before any connection attempt the values
112 returned are those set by the application itself.
114 Applications do not have to call BIO_do_connect() but may wish to do
115 so to separate the connection process from other I/O processing.
117 If non blocking I/O is set then retries will be requested as appropriate.
119 It addition to BIO_should_read() and BIO_should_write() it is also
120 possible for BIO_should_io_special() to be true during the initial
121 connection process with the reason BIO_RR_CONNECT. If this is returned
122 then this is an indication that a connection attempt would block,
123 the application should then take appropriate action to wait until
124 the underlying socket has connected and retry the call.
126 BIO_set_conn_hostname(), BIO_set_conn_port(), BIO_set_conn_ip(),
127 BIO_set_conn_int_port(), BIO_get_conn_hostname(), BIO_get_conn_port(),
128 BIO_get_conn_ip(), BIO_get_conn_int_port(), BIO_set_nbio() and
129 BIO_do_connect() are macros.
133 BIO_s_connect() returns the connect BIO method.
135 BIO_get_fd() returns the socket or -1 if the BIO has not
138 BIO_set_conn_hostname(), BIO_set_conn_port(), BIO_set_conn_ip() and
139 BIO_set_conn_int_port() always return 1.
141 BIO_get_conn_hostname() returns the connected hostname or NULL is
144 BIO_get_conn_port() returns a string representing the connected
145 port or NULL if not set.
147 BIO_get_conn_ip() returns a pointer to the connected IP address in
148 binary form or all zeros if not set.
150 BIO_get_conn_int_port() returns the connected port or 0 if none was
153 BIO_set_nbio() always returns 1.
155 BIO_do_connect() returns 1 if the connection was successfully
156 established and 0 or -1 if the connection failed.
160 This is example connects to a webserver on the local host and attempts
161 to retrieve a page and copy the result to standard output.
168 cbio = BIO_new_connect("localhost:http");
169 out = BIO_new_fp(stdout, BIO_NOCLOSE);
170 if (BIO_do_connect(cbio) <= 0) {
171 fprintf(stderr, "Error connecting to server\n");
172 ERR_print_errors_fp(stderr);
175 BIO_puts(cbio, "GET / HTTP/1.0\n\n");
177 len = BIO_read(cbio, tmpbuf, 1024);
180 BIO_write(out, tmpbuf, len);
192 Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
194 Licensed under the OpenSSL license (the "License"). You may not use
195 this file except in compliance with the License. You can obtain a copy
196 in the file LICENSE in the source distribution or at
197 L<https://www.openssl.org/source/license.html>.