Manual Pages for UNIX Operating System command usage for man SSL_get_info_callback

OpenSSL                       SSL_CTX_set_info_callback(3openssl)



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     SSL_CTX_set_info_callback, SSL_CTX_get_info_callback,
     SSL_set_info_callback, SSL_get_info_callback - handle
     information callback for SSL connections

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      #include 

      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))();


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

     SSL_set_info_callback() sets the ccccaaaallllllllbbbbaaaacccckkkk function, that can
     be used to obtain state information for ssssssssllll during
     connection setup and use.  When ccccaaaallllllllbbbbaaaacccckkkk is NULL, the
     callback setting currently valid for ccccttttxxxx is used.

     SSL_CTX_get_info_callback() returns a pointer to the
     currently set information callback function for ccccttttxxxx.

     SSL_get_info_callback() returns a pointer to the currently
     set information callback function for ssssssssllll.

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     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 ccccaaaallllllllbbbbaaaacccckkkk((((SSSSSSSSLLLL ****ssssssssllll,,,, iiiinnnntttt
     wwwwhhhheeeerrrreeee,,,, iiiinnnntttt rrrreeeetttt)))).  The wwwwhhhheeeerrrreeee argument specifies information
     about where (in which context) the callback function was
     called. If rrrreeeetttt is 0, an error condition occurred.  If an
     alert is handled, SSL_CB_ALERT is set and rrrreeeetttt specifies the
     alert information.

     wwwwhhhheeeerrrreeee is a bitmask made up of the following bits:

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



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OpenSSL                       SSL_CTX_set_info_callback(3openssl)



     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.)

     SSL_CB_READ
         Callback has been called during read operation.

     SSL_CB_WRITE
         Callback has been called during write operation.

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

     SSL_CB_READ_ALERT               (SSL_CB_ALERT|SSL_CB_READ)

     SSL_CB_WRITE_ALERT              (SSL_CB_ALERT|SSL_CB_WRITE)

     SSL_CB_ACCEPT_LOOP              (SSL_ST_ACCEPT|SSL_CB_LOOP)

     SSL_CB_ACCEPT_EXIT              (SSL_ST_ACCEPT|SSL_CB_EXIT)

     SSL_CB_CONNECT_LOOP             (SSL_ST_CONNECT|SSL_CB_LOOP)

     SSL_CB_CONNECT_EXIT             (SSL_ST_CONNECT|SSL_CB_EXIT)

     SSL_CB_HANDSHAKE_START
         Callback has been called because a new handshake is
         started.

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

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

     The rrrreeeetttt information can be evaluated using the
     SSL_alert_type_string(3) family of functions.

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     SSL_set_info_callback() does not provide diagnostic
     information.

     SSL_get_info_callback() returns the current setting.

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




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OpenSSL                       SSL_CTX_set_info_callback(3openssl)



      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\n",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\n",
                             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\n",
                                     str,SSL_state_string_long(s));
                     else if (ret < 0)
                             {
                             BIO_printf(bio_err,"%s:error in %s\n",
                                     str,SSL_state_string_long(s));
                             }
                     }
             }


SSSSEEEEEEEE AAAALLLLSSSSOOOO
     ssl(3), SSL_state_string(3), SSL_alert_type_string(3)
















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OpenSSL                       SSL_CTX_set_info_callback(3openssl)























































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