5 BIO_set_conn_address, BIO_get_conn_address,
6 BIO_s_connect, BIO_new_connect, BIO_set_conn_hostname, BIO_set_conn_port,
7 BIO_set_conn_ip_family, BIO_get_conn_ip_family,
8 BIO_get_conn_hostname, BIO_get_conn_port,
9 BIO_set_nbio, BIO_do_connect - connect BIO
13 #include <openssl/bio.h>
15 const BIO_METHOD * BIO_s_connect(void);
17 BIO *BIO_new_connect(char *name);
19 long BIO_set_conn_hostname(BIO *b, char *name);
20 long BIO_set_conn_port(BIO *b, char *port);
21 long BIO_set_conn_address(BIO *b, BIO_ADDR *addr);
22 long BIO_set_conn_ip_family(BIO *b, long family);
23 const char *BIO_get_conn_hostname(BIO *b);
24 const char *BIO_get_conn_port(BIO *b);
25 const BIO_ADDR *BIO_get_conn_address(BIO *b);
26 const long BIO_get_conn_ip_family(BIO *b);
28 long BIO_set_nbio(BIO *b, long n);
30 int BIO_do_connect(BIO *b);
34 BIO_s_connect() returns the connect BIO method. This is a wrapper
35 round the platform's TCP/IP socket connection routines.
37 Using connect BIOs, TCP/IP connections can be made and data
38 transferred using only BIO routines. In this way any platform
39 specific operations are hidden by the BIO abstraction.
41 Read and write operations on a connect BIO will perform I/O
42 on the underlying connection. If no connection is established
43 and the port and hostname (see below) is set up properly then
44 a connection is established first.
46 Connect BIOs support BIO_puts() but not BIO_gets().
48 If the close flag is set on a connect BIO then any active
49 connection is shutdown and the socket closed when the BIO
52 Calling BIO_reset() on a connect BIO will close any active
53 connection and reset the BIO into a state where it can connect
54 to the same host again.
56 BIO_get_fd() places the underlying socket in B<c> if it is not NULL,
57 it also returns the socket . If B<c> is not NULL it should be of
60 BIO_set_conn_hostname() uses the string B<name> to set the hostname.
61 The hostname can be an IP address; if the address is an IPv6 one, it
62 must be enclosed with brackets. The hostname can also include the
63 port in the form hostname:port.
65 BIO_set_conn_port() sets the port to B<port>. B<port> can be the
66 numerical form or a string such as "http". A string will be looked
67 up first using getservbyname() on the host platform but if that
68 fails a standard table of port names will be used. This internal
69 list is http, telnet, socks, https, ssl, ftp, and gopher.
71 BIO_set_conn_address() sets the address and port information using
74 BIO_set_conn_ip_family() sets the IP family.
76 BIO_get_conn_hostname() returns the hostname of the connect BIO or
77 NULL if the BIO is initialized but no hostname is set.
78 This return value is an internal pointer which should not be modified.
80 BIO_get_conn_port() returns the port as a string.
81 This return value is an internal pointer which should not be modified.
83 BIO_get_conn_address() returns the address information as a BIO_ADDR.
84 This return value is an internal pointer which should not be modified.
86 BIO_get_conn_ip_family() returns the IP family of the connect BIO.
88 BIO_set_nbio() sets the non blocking I/O flag to B<n>. If B<n> is
89 zero then blocking I/O is set. If B<n> is 1 then non blocking I/O
90 is set. Blocking I/O is the default. The call to BIO_set_nbio()
91 should be made before the connection is established because
92 non blocking I/O is set during the connect process.
94 BIO_new_connect() combines BIO_new() and BIO_set_conn_hostname() into
95 a single call: that is it creates a new connect BIO with B<name>.
97 BIO_do_connect() attempts to connect the supplied BIO.
98 This performs an SSL/TLS handshake as far as supported by the BIO.
99 For non-SSL BIOs the connection is done typically at TCP level.
100 If domain name resolution yields multiple IP addresses all of them are tried
101 after connect() failures.
102 The function returns 1 if the connection was established successfully.
103 A zero or negative value is returned if the connection could not be established.
104 The call BIO_should_retry() should be used for non blocking connect BIOs
105 to determine if the call should be retried.
106 If a connection has already been established this call has no effect.
110 If blocking I/O is set then a non positive return value from any
111 I/O call is caused by an error condition, although a zero return
112 will normally mean that the connection was closed.
114 If the port name is supplied as part of the hostname then this will
115 override any value set with BIO_set_conn_port(). This may be undesirable
116 if the application does not wish to allow connection to arbitrary
117 ports. This can be avoided by checking for the presence of the ':'
118 character in the passed hostname and either indicating an error or
119 truncating the string at that point.
121 The values returned by BIO_get_conn_hostname(), BIO_get_conn_address(),
122 and BIO_get_conn_port() are updated when a connection attempt is made.
123 Before any connection attempt the values returned are those set by the
126 Applications do not have to call BIO_do_connect() but may wish to do
127 so to separate the connection process from other I/O processing.
129 If non blocking I/O is set then retries will be requested as appropriate.
131 It addition to BIO_should_read() and BIO_should_write() it is also
132 possible for BIO_should_io_special() to be true during the initial
133 connection process with the reason BIO_RR_CONNECT. If this is returned
134 then this is an indication that a connection attempt would block,
135 the application should then take appropriate action to wait until
136 the underlying socket has connected and retry the call.
138 BIO_set_conn_hostname(), BIO_set_conn_port(), BIO_get_conn_hostname(),
139 BIO_set_conn_address(), BIO_get_conn_port(), BIO_get_conn_address(),
140 BIO_set_conn_ip_family(), BIO_get_conn_ip_family(),
141 BIO_set_nbio(), and BIO_do_connect() are macros.
145 BIO_s_connect() returns the connect BIO method.
147 BIO_get_fd() returns the socket or -1 if the BIO has not
150 BIO_set_conn_address(), BIO_set_conn_port(), and BIO_set_conn_ip_family()
153 BIO_set_conn_hostname() returns 1 on success and 0 on failure.
155 BIO_get_conn_address() returns the address information or NULL if none
158 BIO_get_conn_hostname() returns the connected hostname or NULL if
161 BIO_get_conn_ip_family() returns the address family or -1 if none was set.
163 BIO_get_conn_port() returns a string representing the connected
164 port or NULL if not set.
166 BIO_set_nbio() always returns 1.
168 BIO_do_connect() returns 1 if the connection was successfully
169 established and 0 or -1 if the connection failed.
173 This is example connects to a webserver on the local host and attempts
174 to retrieve a page and copy the result to standard output.
181 cbio = BIO_new_connect("localhost:http");
182 out = BIO_new_fp(stdout, BIO_NOCLOSE);
183 if (BIO_do_connect(cbio) <= 0) {
184 fprintf(stderr, "Error connecting to server\n");
185 ERR_print_errors_fp(stderr);
188 BIO_puts(cbio, "GET / HTTP/1.0\n\n");
190 len = BIO_read(cbio, tmpbuf, 1024);
193 BIO_write(out, tmpbuf, len);
205 BIO_set_conn_int_port(), BIO_get_conn_int_port(), BIO_set_conn_ip(), and BIO_get_conn_ip()
206 were removed in OpenSSL 1.1.0.
207 Use BIO_set_conn_address() and BIO_get_conn_address() instead.
211 Copyright 2000-2020 The OpenSSL Project Authors. All Rights Reserved.
213 Licensed under the Apache License 2.0 (the "License"). You may not use
214 this file except in compliance with the License. You can obtain a copy
215 in the file LICENSE in the source distribution or at
216 L<https://www.openssl.org/source/license.html>.