/usr/man/cat.1/openssl-s_time.1(/usr/man/cat.1/openssl-s_time.1)



S_TIME(1)                    OpenSSL                    S_TIME(1)

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] [-verify 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 measurements. It measures the
     number of connections within a given timeframe, 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 verification.  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 information. These are also used

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S_TIME(1)                    OpenSSL                    S_TIME(1)

         when building the client certificate chain.

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

     -new
         performs the timing test using a new session ID for each
         connection.  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 compatible 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; others 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

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S_TIME(1)                    OpenSSL                    S_TIME(1)

         determine how many connections 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.