Manual Pages for UNIX Operating System command usage for man SSL_get_msg_callback_arg

OpenSSL                        SSL_CTX_set_msg_callback(3openssl)



NNNNAAAAMMMMEEEE
     SSL_CTX_set_msg_callback, SSL_CTX_set_msg_callback_arg,
     SSL_set_msg_callback, SSL_get_msg_callback_arg - install
     callback for observing protocol messages

SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS
      #include 

      void SSL_CTX_set_msg_callback(SSL_CTX *ctx, void (*cb)(int write_p, int version, int content_type, const void *buf, size_t len, SSL *ssl, void *arg));
      void SSL_CTX_set_msg_callback_arg(SSL_CTX *ctx, void *arg);

      void SSL_set_msg_callback(SSL_CTX *ctx, void (*cb)(int write_p, int version, int content_type, const void *buf, size_t len, SSL *ssl, void *arg));
      void SSL_set_msg_callback_arg(SSL_CTX *ctx, void *arg);


DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
     SSL_CTX_set_msg_callback() or SSL_set_msg_callback() can be
     used to define a message callback function cb for observing
     all SSL/TLS protocol messages (such as handshake messages)
     that are received or sent.  SSL_CTX_set_msg_callback_arg()
     and SSL_set_msg_callback_arg() can be used to set argument
     arg to the callback function, which is available for
     arbitrary application use.

     SSL_CTX_set_msg_callback() and
     SSL_CTX_set_msg_callback_arg() specify default settings that
     will be copied to new SSSSSSSSLLLL objects by SSL_new(3).
     SSL_set_msg_callback() and SSL_set_msg_callback_arg() modify
     the actual settings of an SSSSSSSSLLLL object. Using a 0000 pointer for
     cb disables the message callback.

     When cb is called by the SSL/TLS library for a protocol
     message, the function arguments have the following meaning:

     write_p
         This flag is 0000 when a protocol message has been received
         and 1111 when a protocol message has been sent.

     version
         The protocol version according to which the protocol
         message is interpreted by the library. Currently, this
         is one of SSSSSSSSLLLL2222_VVVVEEEERRRRSSSSIIIIOOOONNNN, SSSSSSSSLLLL3333_VVVVEEEERRRRSSSSIIIIOOOONNNN and TTTTLLLLSSSS1111_VVVVEEEERRRRSSSSIIIIOOOONNNN
         (for SSL 2.0, SSL 3.0 and TLS 1.0, respectively).

     content_type
         In the case of SSL 2.0, this is always 0000.  In the case
         of SSL 3.0 or TLS 1.0, this is one of the CCCCoooonnnntttteeeennnnttttTTTTyyyyppppeeee
         values defined in the protocol specification
         (cccchhhhaaaannnnggggeeee_cccciiiipppphhhheeeerrrr_ssssppppeeeecccc((((22220000)))), aaaalllleeeerrrrtttt((((22221111)))), hhhhaaaannnnddddsssshhhhaaaakkkkeeee((((22222222)))); but
         never aaaapppppppplllliiiiccccaaaattttiiiioooonnnn_ddddaaaattttaaaa((((22223333)))) because the callback will
         only be called for protocol messages).




15/Aug/2002            Last change: 0.9.8o                      1






OpenSSL                        SSL_CTX_set_msg_callback(3openssl)



     buf, len
         buf points to a buffer containing the protocol message,
         which consists of len bytes. The buffer is no longer
         valid after the callback function has returned.

     ssl The SSSSSSSSLLLL object that received or sent the message.

     arg The user-defined argument optionally defined by
         SSL_CTX_set_msg_callback_arg() or
         SSL_set_msg_callback_arg().

NNNNOOOOTTTTEEEESSSS
     Protocol messages are passed to the callback function after
     decryption and fragment collection where applicable. (Thus
     record boundaries are not visible.)

     If processing a received protocol message results in an
     error, the callback function may not be called.  For
     example, the callback function will never see messages that
     are considered too large to be processed.

     Due to automatic protocol version negotiation, version is
     not necessarily the protocol version used by the sender of
     the message: If a TLS 1.0 ClientHello message is received by
     an SSL 3.0-only server, version will be SSSSSSSSLLLL3333_VVVVEEEERRRRSSSSIIIIOOOONNNN.

SSSSEEEEEEEE AAAALLLLSSSSOOOO
     ssl(3), SSL_new(3)

HHHHIIIISSSSTTTTOOOORRRRYYYY
     SSL_CTX_set_msg_callback(), SSL_CTX_set_msg_callback_arg(),
     SSL_set_msg_callback() and SSL_get_msg_callback_arg() were
     added in OpenSSL 0.9.7.






















15/Aug/2002            Last change: 0.9.8o                      2