← Back
Editing: BIO_s_connect.3
.\" Automatically generated by Pod::Man 4.11 (Pod::Simple 3.35) .\" .\" Standard preamble: .\" ======================================================================== .de Sp \" Vertical space (when we can't use .PP) .if t .sp .5v .if n .sp .. .de Vb \" Begin verbatim text .ft CW .nf .ne \\$1 .. .de Ve \" End verbatim text .ft R .fi .. .\" Set up some character translations and predefined strings. \*(-- will .\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left .\" double quote, and \*(R" will give a right double quote. \*(C+ will .\" give a nicer C++. Capital omega is used to do unbreakable dashes and .\" therefore won't be available. \*(C` and \*(C' expand to `' in nroff, .\" nothing in troff, for use with C<>. .tr \(*W- .ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p' .ie n \{\ . ds -- \(*W- . ds PI pi . if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch . if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch . ds L" "" . ds R" "" . ds C` "" . ds C' "" 'br\} .el\{\ . ds -- \|\(em\| . ds PI \(*p . ds L" `` . ds R" '' . ds C` . ds C' 'br\} .\" .\" Escape single quotes in literal strings from groff's Unicode transform. .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" .\" If the F register is >0, we'll generate index entries on stderr for .\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index .\" entries marked with X<> in POD. Of course, you'll have to process the .\" output yourself in some meaningful fashion. .\" .\" Avoid warning from groff about undefined register 'F'. .de IX .. .nr rF 0 .if \n(.g .if rF .nr rF 1 .if (\n(rF:(\n(.g==0)) \{\ . if \nF \{\ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{\ . nr % 0 . nr F 2 . \} . \} .\} .rr rF .\" .\" Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2). .\" Fear. Run. Save yourself. No user-serviceable parts. . \" fudge factors for nroff and troff .if n \{\ . ds #H 0 . ds #V .8m . ds #F .3m . ds #[ \f1 . ds #] \fP .\} .if t \{\ . ds #H ((1u-(\\\\n(.fu%2u))*.13m) . ds #V .6m . ds #F 0 . ds #[ \& . ds #] \& .\} . \" simple accents for nroff and troff .if n \{\ . ds ' \& . ds ` \& . ds ^ \& . ds , \& . ds ~ ~ . ds / .\} .if t \{\ . ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u" . ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u' . ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u' . ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u' . ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u' . ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u' .\} . \" troff and (daisy-wheel) nroff accents .ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V' .ds 8 \h'\*(#H'\(*b\h'-\*(#H' .ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#] .ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H' .ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u' .ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#] .ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#] .ds ae a\h'-(\w'a'u*4/10)'e .ds Ae A\h'-(\w'A'u*4/10)'E . \" corrections for vroff .if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u' .if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u' . \" for low resolution devices (crt and lpr) .if \n(.H>23 .if \n(.V>19 \ \{\ . ds : e . ds 8 ss . ds o a . ds d- d\h'-1'\(ga . ds D- D\h'-1'\(hy . ds th \o'bp' . ds Th \o'LP' . ds ae ae . ds Ae AE .\} .rm #[ #] #H #V #F C .\" ======================================================================== .\" .IX Title "BIO_S_CONNECT 3" .TH BIO_S_CONNECT 3 "2023-09-11" "1.1.1w" "OpenSSL" .\" For nroff, turn off justification. Always turn off hyphenation; it makes .\" way too many mistakes in technical documents. .if n .ad l .nh .SH "NAME" BIO_set_conn_address, BIO_get_conn_address, BIO_s_connect, BIO_new_connect, BIO_set_conn_hostname, BIO_set_conn_port, BIO_set_conn_ip_family, BIO_get_conn_ip_family, BIO_get_conn_hostname, BIO_get_conn_port, BIO_set_nbio, BIO_do_connect \- connect BIO .SH "SYNOPSIS" .IX Header "SYNOPSIS" .Vb 1 \& #include <openssl/bio.h> \& \& const BIO_METHOD * BIO_s_connect(void); \& \& BIO *BIO_new_connect(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_do_connect(BIO *b); .Ve .SH "DESCRIPTION" .IX Header "DESCRIPTION" \&\fBBIO_s_connect()\fR returns the connect \s-1BIO\s0 method. This is a wrapper round the platform's \s-1TCP/IP\s0 socket connection routines. .PP Using connect BIOs, \s-1TCP/IP\s0 connections can be made and data transferred using only \s-1BIO\s0 routines. In this way any platform specific operations are hidden by the \s-1BIO\s0 abstraction. .PP Read and write operations on a connect \s-1BIO\s0 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. .PP Connect BIOs support \fBBIO_puts()\fR but not \fBBIO_gets()\fR. .PP If the close flag is set on a connect \s-1BIO\s0 then any active connection is shutdown and the socket closed when the \s-1BIO\s0 is freed. .PP Calling \fBBIO_reset()\fR on a connect \s-1BIO\s0 will close any active connection and reset the \s-1BIO\s0 into a state where it can connect to the same host again. .PP \&\fBBIO_get_fd()\fR places the underlying socket in \fBc\fR if it is not \s-1NULL,\s0 it also returns the socket . If \fBc\fR is not \s-1NULL\s0 it should be of type (int *). .PP \&\fBBIO_set_conn_hostname()\fR uses the string \fBname\fR to set the hostname. The hostname can be an \s-1IP\s0 address; if the address is an IPv6 one, it must be enclosed with brackets. The hostname can also include the port in the form hostname:port. .PP \&\fBBIO_set_conn_port()\fR sets the port to \fBport\fR. \fBport\fR can be the numerical form or a string such as \*(L"http\*(R". A string will be looked up first using \fBgetservbyname()\fR on the host platform but if that fails a standard table of port names will be used. This internal list is http, telnet, socks, https, ssl, ftp, and gopher. .PP \&\fBBIO_set_conn_address()\fR sets the address and port information using a \s-1\fBBIO_ADDR\s0\fR\|(3ssl). .PP \&\fBBIO_set_conn_ip_family()\fR sets the \s-1IP\s0 family. .PP \&\fBBIO_get_conn_hostname()\fR returns the hostname of the connect \s-1BIO\s0 or \&\s-1NULL\s0 if the \s-1BIO\s0 is initialized but no hostname is set. This return value is an internal pointer which should not be modified. .PP \&\fBBIO_get_conn_port()\fR returns the port as a string. This return value is an internal pointer which should not be modified. .PP \&\fBBIO_get_conn_address()\fR returns the address information as a \s-1BIO_ADDR.\s0 This return value is an internal pointer which should not be modified. .PP \&\fBBIO_get_conn_ip_family()\fR returns the \s-1IP\s0 family of the connect \s-1BIO.\s0 .PP \&\fBBIO_set_nbio()\fR sets the non blocking I/O flag to \fBn\fR. If \fBn\fR is zero then blocking I/O is set. If \fBn\fR is 1 then non blocking I/O is set. Blocking I/O is the default. The call to \fBBIO_set_nbio()\fR should be made before the connection is established because non blocking I/O is set during the connect process. .PP \&\fBBIO_new_connect()\fR combines \fBBIO_new()\fR and \fBBIO_set_conn_hostname()\fR into a single call: that is it creates a new connect \s-1BIO\s0 with \fBname\fR. .PP \&\fBBIO_do_connect()\fR attempts to connect the supplied \s-1BIO.\s0 It returns 1 if the connection was established successfully. A zero or negative value is returned if the connection could not be established, the call \fBBIO_should_retry()\fR should be used for non blocking connect BIOs to determine if the call should be retried. .SH "NOTES" .IX Header "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. .PP If the port name is supplied as part of the hostname then this will override any value set with \fBBIO_set_conn_port()\fR. 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. .PP The values returned by \fBBIO_get_conn_hostname()\fR, \fBBIO_get_conn_address()\fR, and \fBBIO_get_conn_port()\fR are updated when a connection attempt is made. Before any connection attempt the values returned are those set by the application itself. .PP Applications do not have to call \fBBIO_do_connect()\fR but may wish to do so to separate the connection process from other I/O processing. .PP If non blocking I/O is set then retries will be requested as appropriate. .PP It addition to \fBBIO_should_read()\fR and \fBBIO_should_write()\fR it is also possible for \fBBIO_should_io_special()\fR to be true during the initial connection process with the reason \s-1BIO_RR_CONNECT.\s0 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. .PP \&\fBBIO_set_conn_hostname()\fR, \fBBIO_set_conn_port()\fR, \fBBIO_get_conn_hostname()\fR, \&\fBBIO_set_conn_address()\fR, \fBBIO_get_conn_port()\fR, \fBBIO_get_conn_address()\fR, \&\fBBIO_set_conn_ip_family()\fR, \fBBIO_get_conn_ip_family()\fR, \&\fBBIO_set_nbio()\fR, and \fBBIO_do_connect()\fR are macros. .SH "RETURN VALUES" .IX Header "RETURN VALUES" \&\fBBIO_s_connect()\fR returns the connect \s-1BIO\s0 method. .PP \&\fBBIO_get_fd()\fR returns the socket or \-1 if the \s-1BIO\s0 has not been initialized. .PP \&\fBBIO_set_conn_address()\fR, \fBBIO_set_conn_port()\fR, and \fBBIO_set_conn_ip_family()\fR always return 1. .PP \&\fBBIO_set_conn_hostname()\fR returns 1 on success and 0 on failure. .PP \&\fBBIO_get_conn_address()\fR returns the address information or \s-1NULL\s0 if none was set. .PP \&\fBBIO_get_conn_hostname()\fR returns the connected hostname or \s-1NULL\s0 if none was set. .PP \&\fBBIO_get_conn_ip_family()\fR returns the address family or \-1 if none was set. .PP \&\fBBIO_get_conn_port()\fR returns a string representing the connected port or \s-1NULL\s0 if not set. .PP \&\fBBIO_set_nbio()\fR always returns 1. .PP \&\fBBIO_do_connect()\fR returns 1 if the connection was successfully established and 0 or \-1 if the connection failed. .SH "EXAMPLES" .IX Header "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. .PP .Vb 3 \& 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\en"); \& ERR_print_errors_fp(stderr); \& exit(1); \& } \& BIO_puts(cbio, "GET / HTTP/1.0\en\en"); \& for (;;) { \& len = BIO_read(cbio, tmpbuf, 1024); \& if (len <= 0) \& break; \& BIO_write(out, tmpbuf, len); \& } \& BIO_free(cbio); \& BIO_free(out); .Ve .SH "SEE ALSO" .IX Header "SEE ALSO" \&\s-1\fBBIO_ADDR\s0\fR\|(3) .SH "HISTORY" .IX Header "HISTORY" \&\fBBIO_set_conn_int_port()\fR, \fBBIO_get_conn_int_port()\fR, \fBBIO_set_conn_ip()\fR, and \fBBIO_get_conn_ip()\fR were removed in OpenSSL 1.1.0. Use \fBBIO_set_conn_address()\fR and \fBBIO_get_conn_address()\fR instead. .SH "COPYRIGHT" .IX Header "COPYRIGHT" Copyright 2000\-2020 The OpenSSL Project Authors. All Rights Reserved. .PP Licensed under the OpenSSL license (the \*(L"License\*(R"). You may not use this file except in compliance with the License. You can obtain a copy in the file \s-1LICENSE\s0 in the source distribution or at <https://www.openssl.org/source/license.html>.
Save File
Cancel