Hi, i find way to show exchange of digital certificates information.

i'm sorry, I did not read the document

http://wiki.nginx.org/HttpSslModule

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Module ngx_http_ssl_module supports the following built-in variables:

$ssl_cipher returns the cipher suite being used for the currently established SSL/TLS connection
$ssl_client_serial returns the serial number of the client certificate for the currently established SSL/TLS connection — if applicable, i.e., if client authentication is activated in the connection
$ssl_client_s_dn returns the subject Distinguished Name (DN) of the client certificate for the currently established SSL/TLS connection — if applicable, i.e., if client authentication is activated in the connection
$ssl_client_i_dn returns the issuer DN of the client certificate for the currently established SSL/TLS connection — if applicable, i.e., if client authentication is activated in the connection
$ssl_protocol returns the protocol of the currently established SSL/TLS connection — depending on the configuration and client available options it's one of SSLv2, SSLv3 or TLSv1
$ssl_session_id the Session ID of the established secure connection — requires Nginx version greater or equal to 0.8.20
$ssl_client_cert
$ssl_client_raw_cert
$ssl_client_verify takes the value "SUCCESS" when the client certificate is successfully verified