manpagez: man pages & more
man BIO_set_conn_ip(3)
Home | html | info | man
BIO_S_CONNECT(3ossl)                OpenSSL               BIO_S_CONNECT(3ossl)



NAME

       BIO_s_connect, BIO_new_connect, BIO_set_conn_hostname,
       BIO_set_conn_port, BIO_set_conn_address, BIO_set_conn_ip_family,
       BIO_get_conn_hostname, BIO_get_conn_port, BIO_get_conn_address,
       BIO_get_conn_ip_family, BIO_set_nbio, BIO_set_sock_type,
       BIO_get_sock_type, BIO_get0_dgram_bio, BIO_do_connect - connect BIO


SYNOPSIS

        #include <openssl/bio.h>

        const BIO_METHOD *BIO_s_connect(void);

        BIO *BIO_new_connect(const char *name);

        long BIO_set_conn_hostname(BIO *b, char *name);
        long BIO_set_conn_port(BIO *b, char *port);
        long BIO_set_conn_address(BIO *b, BIO_ADDR *addr);
        long BIO_set_conn_ip_family(BIO *b, long family);
        const char *BIO_get_conn_hostname(BIO *b);
        const char *BIO_get_conn_port(BIO *b);
        const BIO_ADDR *BIO_get_conn_address(BIO *b);
        const long BIO_get_conn_ip_family(BIO *b);

        long BIO_set_nbio(BIO *b, long n);

        int BIO_set_sock_type(BIO *b, int sock_type);
        int BIO_get_sock_type(BIO *b);
        int BIO_get0_dgram_bio(BIO *B, BIO **dgram_bio);

        long BIO_do_connect(BIO *b);


DESCRIPTION

       BIO_s_connect(3) 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 (see below) is set up properly then a connection is
       established first.

       Connect BIOs support BIO_puts() and 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.

       BIO_new_connect() combines BIO_new() and BIO_set_conn_hostname() into a
       single call: that is it creates a new connect BIO with hostname name.

       BIO_set_conn_hostname() uses the string name to set the hostname.  The
       hostname can be an IP address; if the address is an IPv6 one, it must
       be enclosed with brackets "[" and "]".  The hostname can also include
       the port in the form hostname:port; see BIO_parse_hostserv(3) and
       BIO_set_conn_port() for details.

       BIO_set_conn_port() sets the port to port. port can be the numerical
       form or a service string such as "http", which will be mapped to a port
       number using the system function getservbyname().

       BIO_set_conn_address() sets the address and port information using a
       BIO_ADDR(3ssl).

       BIO_set_conn_ip_family() sets the IP family.

       BIO_get_conn_hostname() 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.

       BIO_get_conn_port() returns the port as a string.  This return value is
       an internal pointer which should not be modified.

       BIO_get_conn_address() returns the address information as a BIO_ADDR.
       This return value is an internal pointer which should not be modified.

       BIO_get_conn_ip_family() returns the IP family of the connect BIO.

       BIO_set_nbio() 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 non blocking I/O is set during
       the connect process.

       BIO_do_connect() attempts to connect the supplied BIO. This performs an
       SSL/TLS handshake as far as supported by the BIO. For non-SSL BIOs the
       connection is done typically at TCP level.  If domain name resolution
       yields multiple IP addresses all of them are tried after connect()
       failures.  The function returns 1 if the connection was established
       successfully.  A zero or negative value is returned if the connection
       could not be established.  The call BIO_should_retry() should be used
       for non blocking connect BIOs to determine if the call should be
       retried.  If a connection has already been established this call has no
       effect.

       BIO_set_sock_type() can be used to set a socket type value as would be
       passed in a call to socket(2). The only currently supported values are
       SOCK_STREAM (the default) and SOCK_DGRAM. If SOCK_DGRAM is configured,
       the connection created is a UDP datagram socket handled via
       BIO_s_datagram(3).  I/O calls such as BIO_read(3) and BIO_write(3) are
       forwarded transparently to an internal BIO_s_datagram(3) instance. The
       created BIO_s_datagram(3) instance can be retrieved using
       BIO_get0_dgram_bio() if desired, which writes a pointer to the
       BIO_s_datagram(3) instance to *dgram_bio. The lifetime of the internal
       BIO_s_connect(3) and does not need to be
       freed by the caller.

       BIO_get_sock_type() retrieves the value set using BIO_set_sock_type().


NOTES

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

       If the port name is supplied as part of the hostname then this will
       override any value set with BIO_set_conn_port(). This may 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 ':' 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_address(),
       and BIO_get_conn_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 non blocking 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.

       BIO_set_conn_hostname(), BIO_set_conn_port(), BIO_get_conn_hostname(),
       BIO_set_conn_address(), BIO_get_conn_port(), BIO_get_conn_address(),
       BIO_set_conn_ip_family(), BIO_get_conn_ip_family(), BIO_set_nbio(), and
       BIO_do_connect() are macros.


RETURN VALUES

       BIO_s_connect(3) returns the connect BIO method.

       BIO_set_conn_address(), BIO_set_conn_port(), and
       BIO_set_conn_ip_family() return 1 or <=0 if an error occurs.

       BIO_set_conn_hostname() returns 1 on success and <=0 on failure.

       BIO_get_conn_address() returns the address information or NULL if none
       was set.

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

       BIO_get_conn_ip_family() returns the address family or -1 if none was
       set.

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

       BIO_set_nbio() returns 1 or <=0 if an error occurs.

       BIO_do_connect() returns 1 if the connection was successfully
       established and <=0 if the connection failed.

       BIO_set_sock_type() returns 1 on success or 0 on failure.

       BIO_get_sock_type() returns a socket type or 0 if the call is not
       supported.

       BIO_get0_dgram_bio() returns 1 on success or 0 on failure.


EXAMPLES

       This is 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];

        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);
            exit(1);
        }
        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

       BIO_ADDR(3), BIO_parse_hostserv(3)


HISTORY

       BIO_set_conn_int_port(), BIO_get_conn_int_port(), BIO_set_conn_ip(),
       and BIO_get_conn_ip() were removed in OpenSSL 1.1.0.  Use
       BIO_set_conn_address() and BIO_get_conn_address() instead.

       Connect BIOs support BIO_gets() since OpenSSL 3.2.


COPYRIGHT

       Copyright 2000-2023 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the Apache License 2.0 (the "License").  You may not use
       this file except in compliance with the License.  You can obtain a copy
       in the file LICENSE in the source distribution or at
       <https://www.openssl.org/source/license.html>.

3.2.0                             2023-11-23              BIO_S_CONNECT(3ossl)

openssl 3.2.0 - Generated Fri Dec 1 07:48:09 CST 2023
© manpagez.com 2000-2024
Individual documents may contain additional copyright information.