SSLCTXsetinfocallback(3) OpenSSL SSLCTXsetinfocallback(3)

NAME
       SSLCTXsetinfocallback, SSLCTXgetinfocallback,
       SSLsetinfocallback, SSLgetinfocallback - handle information
       callback for SSL connections

SYNOPSIS
        #include 

        void SSLCTXsetinfocallback(SSLCTX *ctx, void (*callback)());
        void (*SSLCTXgetinfocallback(const SSLCTX *ctx))();

        void SSLsetinfocallback(SSL *ssl, void (*callback)());
        void (*SSLgetinfocallback(const SSL *ssl))();

DESCRIPTION
       SSLCTXsetinfocallback() sets the ccaallllbbaacckk function, that can be
       used to obtain state information for SSL objects created from ccttxx
       during connection setup and use. The setting for ccttxx is overridden from
       the setting for a specific SSL object, if specified.  When ccaallllbbaacckk is
       NULL, not callback function is used.

       SSLsetinfocallback() sets the ccaallllbbaacckk function, that can be used to
       obtain state information for ssssll during connection setup and use.  When
       ccaallllbbaacckk is NULL, the callback setting currently valid for ccttxx is used.

       SSLCTXgetinfocallback() returns a pointer to the currently set
       information callback function for ccttxx.

       SSLgetinfocallback() returns a pointer to the currently set
       information callback function for ssssll.

NNOOTTEESS
       When setting up a connection and during use, it is possible to obtain
       state information from the SSL/TLS engine. When set, an information
       callback function is called whenever the state changes, an alert
       appears, or an error occurs.

       The callback function is called as ccaallllbbaacckk((SSSSLL **ssssll,, iinntt wwhheerree,, iinntt
       rreett)).  The wwhheerree argument specifies information about where (in which
       context) the callback function was called. If rreett is 0, an error
       condition occurred.  If an alert is handled, SSLCBALERT is set and
       rreett specifies the alert information.

       wwhheerree is a bitmask made up of the following bits:

       SSLCBLOOP
           Callback has been called to indicate state change inside a loop.

       SSLCBEXIT
           Callback has been called to indicate error exit of a handshake
           function.  (May be soft error with retry option for non-blocking
           setups.)

       SSLCBREAD
           Callback has been called during read operation.

       SSLCBWRITE
           Callback has been called during write operation.

       SSLCBALERT
           Callback has been called due to an alert being sent or received.

       SSLCBREADALERT               (SSLCBALERT|SSLCBREAD)
       SSLCBWRITEALERT              (SSLCBALERT|SSLCBWRITE)
       SSLCBACCEPTLOOP              (SSLSTACCEPT|SSLCBLOOP)
       SSLCBACCEPTEXIT              (SSLSTACCEPT|SSLCBEXIT)
       SSLCBCONNECTLOOP             (SSLSTCONNECT|SSLCBLOOP)
       SSLCBCONNECTEXIT             (SSLSTCONNECT|SSLCBEXIT)
       SSLCBHANDSHAKESTART
           Callback has been called because a new handshake is started.

       SSLCBHANDSHAKEDONE           0x20
           Callback has been called because a handshake is finished.

       The current state information can be obtained using the
       SSLstatestring(3) family of functions.

       The rreett information can be evaluated using the SSLalerttypestring(3)
       family of functions.

RETURN VALUES
       SSLsetinfocallback() does not provide diagnostic information.

       SSLgetinfocallback() returns the current setting.

EEXXAAMMPPLLEESS
       The following example callback function prints state strings,
       information about alerts being handled and error messages to the
       bbiiooeerrrr BIO.

        void appssslinfocallback(SSL *s, int where, int ret)
               {
               const char *str;
               int w;

               w=where& ~SSLSTMASK;

               if (w & SSLSTCONNECT) str="SSLconnect";
               else if (w & SSLSTACCEPT) str="SSLaccept";
               else str="undefined";

               if (where & SSLCBLOOP)
                       {
                       BIOprintf(bioerr,"%s:%s\n",str,SSLstatestringlong(s));
                       }
               else if (where & SSLCBALERT)
                       {
                       str=(where & SSLCBREAD)?"read":"write";
                       BIOprintf(bioerr,"SSL3 alert %s:%s:%s\n",
                               str,
                               SSLalerttypestringlong(ret),
                               SSLalertdescstringlong(ret));
                       }
               else if (where & SSLCBEXIT)
                       {
                       if (ret == 0)
                               BIOprintf(bioerr,"%s:failed in %s\n",
                                       str,SSLstatestringlong(s));
                       else if (ret < 0)
                               {
                               BIOprintf(bioerr,"%s:error in %s\n",
                                       str,SSLstatestringlong(s));
                               }
                       }
               }

SEE ALSO
       ssl(3), SSLstatestring(3), SSLalerttypestring(3)



0.9.7l                            2005-03-30      SSLCTXsetinfocallback(3)