← Back
Editing: SSL_get_info_callback.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 "SSL_CTX_set_info_callback 3" .TH SSL_CTX_set_info_callback 3 "2019-12-20" "1.0.2u" "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" SSL_CTX_set_info_callback, SSL_CTX_get_info_callback, SSL_set_info_callback, SSL_get_info_callback \- handle information callback for SSL connections .SH "SYNOPSIS" .IX Header "SYNOPSIS" .Vb 1 \& #include <openssl/ssl.h> \& \& void SSL_CTX_set_info_callback(SSL_CTX *ctx, void (*callback)()); \& void (*SSL_CTX_get_info_callback(const SSL_CTX *ctx))(); \& \& void SSL_set_info_callback(SSL *ssl, void (*callback)()); \& void (*SSL_get_info_callback(const SSL *ssl))(); .Ve .SH "DESCRIPTION" .IX Header "DESCRIPTION" \&\fBSSL_CTX_set_info_callback()\fR sets the \fBcallback\fR function, that can be used to obtain state information for \s-1SSL\s0 objects created from \fBctx\fR during connection setup and use. The setting for \fBctx\fR is overridden from the setting for a specific \s-1SSL\s0 object, if specified. When \fBcallback\fR is \s-1NULL,\s0 not callback function is used. .PP \&\fBSSL_set_info_callback()\fR sets the \fBcallback\fR function, that can be used to obtain state information for \fBssl\fR during connection setup and use. When \fBcallback\fR is \s-1NULL,\s0 the callback setting currently valid for \&\fBctx\fR is used. .PP \&\fBSSL_CTX_get_info_callback()\fR returns a pointer to the currently set information callback function for \fBctx\fR. .PP \&\fBSSL_get_info_callback()\fR returns a pointer to the currently set information callback function for \fBssl\fR. .SH "NOTES" .IX Header "NOTES" When setting up a connection and during use, it is possible to obtain state information from the \s-1SSL/TLS\s0 engine. When set, an information callback function is called whenever the state changes, an alert appears, or an error occurs. .PP The callback function is called as \fBcallback(\s-1SSL\s0 *ssl, int where, int ret)\fR. The \fBwhere\fR argument specifies information about where (in which context) the callback function was called. If \fBret\fR is 0, an error condition occurred. If an alert is handled, \s-1SSL_CB_ALERT\s0 is set and \fBret\fR specifies the alert information. .PP \&\fBwhere\fR is a bitmask made up of the following bits: .IP "\s-1SSL_CB_LOOP\s0" 4 .IX Item "SSL_CB_LOOP" Callback has been called to indicate state change inside a loop. .IP "\s-1SSL_CB_EXIT\s0" 4 .IX Item "SSL_CB_EXIT" Callback has been called to indicate error exit of a handshake function. (May be soft error with retry option for non-blocking setups.) .IP "\s-1SSL_CB_READ\s0" 4 .IX Item "SSL_CB_READ" Callback has been called during read operation. .IP "\s-1SSL_CB_WRITE\s0" 4 .IX Item "SSL_CB_WRITE" Callback has been called during write operation. .IP "\s-1SSL_CB_ALERT\s0" 4 .IX Item "SSL_CB_ALERT" Callback has been called due to an alert being sent or received. .IP "\s-1SSL_CB_READ_ALERT\s0 (SSL_CB_ALERT|SSL_CB_READ)" 4 .IX Item "SSL_CB_READ_ALERT (SSL_CB_ALERT|SSL_CB_READ)" .PD 0 .IP "\s-1SSL_CB_WRITE_ALERT\s0 (SSL_CB_ALERT|SSL_CB_WRITE)" 4 .IX Item "SSL_CB_WRITE_ALERT (SSL_CB_ALERT|SSL_CB_WRITE)" .IP "\s-1SSL_CB_ACCEPT_LOOP\s0 (SSL_ST_ACCEPT|SSL_CB_LOOP)" 4 .IX Item "SSL_CB_ACCEPT_LOOP (SSL_ST_ACCEPT|SSL_CB_LOOP)" .IP "\s-1SSL_CB_ACCEPT_EXIT\s0 (SSL_ST_ACCEPT|SSL_CB_EXIT)" 4 .IX Item "SSL_CB_ACCEPT_EXIT (SSL_ST_ACCEPT|SSL_CB_EXIT)" .IP "\s-1SSL_CB_CONNECT_LOOP\s0 (SSL_ST_CONNECT|SSL_CB_LOOP)" 4 .IX Item "SSL_CB_CONNECT_LOOP (SSL_ST_CONNECT|SSL_CB_LOOP)" .IP "\s-1SSL_CB_CONNECT_EXIT\s0 (SSL_ST_CONNECT|SSL_CB_EXIT)" 4 .IX Item "SSL_CB_CONNECT_EXIT (SSL_ST_CONNECT|SSL_CB_EXIT)" .IP "\s-1SSL_CB_HANDSHAKE_START\s0" 4 .IX Item "SSL_CB_HANDSHAKE_START" .PD Callback has been called because a new handshake is started. .IP "\s-1SSL_CB_HANDSHAKE_DONE\s0 0x20" 4 .IX Item "SSL_CB_HANDSHAKE_DONE 0x20" Callback has been called because a handshake is finished. .PP The current state information can be obtained using the \&\fBSSL_state_string\fR\|(3) family of functions. .PP The \fBret\fR information can be evaluated using the \&\fBSSL_alert_type_string\fR\|(3) family of functions. .SH "RETURN VALUES" .IX Header "RETURN VALUES" \&\fBSSL_set_info_callback()\fR does not provide diagnostic information. .PP \&\fBSSL_get_info_callback()\fR returns the current setting. .SH "EXAMPLES" .IX Header "EXAMPLES" The following example callback function prints state strings, information about alerts being handled and error messages to the \fBbio_err\fR \s-1BIO.\s0 .PP .Vb 4 \& void apps_ssl_info_callback(SSL *s, int where, int ret) \& { \& const char *str; \& int w; \& \& w=where& ~SSL_ST_MASK; \& \& if (w & SSL_ST_CONNECT) str="SSL_connect"; \& else if (w & SSL_ST_ACCEPT) str="SSL_accept"; \& else str="undefined"; \& \& if (where & SSL_CB_LOOP) \& { \& BIO_printf(bio_err,"%s:%s\en",str,SSL_state_string_long(s)); \& } \& else if (where & SSL_CB_ALERT) \& { \& str=(where & SSL_CB_READ)?"read":"write"; \& BIO_printf(bio_err,"SSL3 alert %s:%s:%s\en", \& str, \& SSL_alert_type_string_long(ret), \& SSL_alert_desc_string_long(ret)); \& } \& else if (where & SSL_CB_EXIT) \& { \& if (ret == 0) \& BIO_printf(bio_err,"%s:failed in %s\en", \& str,SSL_state_string_long(s)); \& else if (ret < 0) \& { \& BIO_printf(bio_err,"%s:error in %s\en", \& str,SSL_state_string_long(s)); \& } \& } \& } .Ve .SH "SEE ALSO" .IX Header "SEE ALSO" \&\fBssl\fR\|(3), \fBSSL_state_string\fR\|(3), \&\fBSSL_alert_type_string\fR\|(3)
Save File
Cancel