/usr/man2/cat.1/s_time.1.Z(/usr/man2/cat.1/s_time.1.Z)

NAME

       openssl-s_time, s_time - SSL/TLS performance timing program

SYNOPSIS

       openssl s_time [-connect host:port] [-www page] [-cert filename] [-key
       filename] [-CApath directory] [-CAfile filename] [-reuse] [-new] [-ver-
       ify depth] [-nbio] [-time seconds] [-ssl2] [-ssl3] [-bugs] [-cipher
       cipherlist]

DESCRIPTION

       The s_time command implements a generic SSL/TLS client which connects
       to a remote host using SSL/TLS. It can request a page from the server
       and includes the time to transfer the payload data in its timing mea-
       surements. It measures the number of connections within a given time-
       frame, the amount of data transferred (if any), and calculates the
       average time spent for one connection.

OPTIONS

       -connect host:port
           This specifies the host and optional port to connect to.

       -www page
           This specifies the page to GET from the server. A value of '/' gets
           the index.htm[l] page. If this parameter is not specified, then
           s_time will only perform the handshake to establish SSL connections
           but not transfer any payload data.

       -cert certname
           The certificate to use, if one is requested by the server. The
           default is not to use a certificate. The file is in PEM format.

       -key keyfile
           The private key to use. If not specified then the certificate file
           will be used. The file is in PEM format.

       -verify depth
           The verify depth to use. This specifies the maximum length of the
           server certificate chain and turns on server certificate verifica-
           tion.  Currently the verify operation continues after errors so all
           the problems with a certificate chain can be seen. As a side effect
           the connection will never fail due to a server certificate verify
           failure.

       -CApath directory
           The directory to use for server certificate verification. This
           directory must be in "hash format", see verify for more informa-
           tion. These are also used when building the client certificate
           chain.

       -CAfile file
           A file containing trusted certificates to use during server authen-
           tication and to use when attempting to build the client certificate
           chain.

       -new
           performs the timing test using a new session ID for each connec-
           tion.  If neither -new nor -reuse are specified, they are both on
           by default and executed in sequence.

       -reuse
           performs the timing test using the same session ID; this can be
           used as a test that session caching is working. If neither -new nor
           -reuse are specified, they are both on by default and executed in
           sequence.

       -nbio
           turns on non-blocking I/O.

       -ssl2, -ssl3
           these options disable the use of certain SSL or TLS protocols. By
           default the initial handshake uses a method which should be compat-
           ible with all servers and permit them to use SSL v3, SSL v2 or TLS
           as appropriate.  The timing program is not as rich in options to
           turn protocols on and off as the s_client(1) program and may not
           connect to all servers.

           Unfortunately there are a lot of ancient and broken servers in use
           which cannot handle this technique and will fail to connect. Some
           servers only work if TLS is turned off with the -ssl3 option; oth-
           ers will only support SSL v2 and may need the -ssl2 option.

       -bugs
           there are several known bug in SSL and TLS implementations. Adding
           this option enables various workarounds.

       -cipher cipherlist
           this allows the cipher list sent by the client to be modified.
           Although the server determines which cipher suite is used it should
           take the first supported cipher in the list sent by the client.
           See the ciphers(1) command for more information.

       -time length
           specifies how long (in seconds) s_time should establish connections
           and optionally transfer payload data from a server. Server and
           client performance and the link speed determine how many connec-
           tions s_time can establish.

NOTES

s_time can be used to measure the performance of an SSL connection. To
connect to an SSL HTTP server and get the default page the command

openssl s_time -connect servername:443 -www / -CApath yourdir -CAfile yourfile.pem -cipher commoncipher [-ssl3]

would typically be used (https uses port 443). 'commoncipher' is a
cipher to which both client and server can agree, see the ciphers(1)
command for details.

If the handshake fails then there are several possible causes, if it is
nothing obvious like no client certificate then the -bugs, -ssl2, -ssl3
options can be tried in case it is a buggy server. In particular you
should play with these options before submitting a bug report to an
OpenSSL mailing list.

A frequent problem when attempting to get client certificates working
is that a web client complains it has no certificates or gives an empty
list to choose from. This is normally because the server is not sending
the clients certificate authority in its "acceptable CA list" when it
requests a certificate. By using s_client(1) the CA list can be viewed
and checked. However some servers only request client authentication
after a specific URL is requested. To obtain the list in this case it
is necessary to use the -prexit option of s_client(1) and send an HTTP
request for an appropriate page.

If a certificate is specified on the command line using the -cert
option it will not be used unless the server specifically requests a
client certificate. Therefor merely including a client certificate on
the command line is no guarantee that the certificate works.

BUGS

       Because this program does not have all the options of the s_client(1)
       program to turn protocols on and off, you may not be able to measure
       the performance of all protocols with all servers.

       The -verify option should really exit if the server verification fails.