NAME

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

SYNOPSIS

       openssl s_time [-help] [-connect host:port] [-www page] [-cert filename] [-key filename] [-CApath
       directory] [-cafile filename] [-no-CAfile] [-no-CApath] [-reuse] [-new] [-verify depth] [-nameopt option]
       [-time seconds] [-ssl3] [-bugs] [-cipher cipherlist] [-ciphersuites val]

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

       -help
           Print out a usage message.

       -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.

       -nameopt option
           Option which determines how the subject or issuer names are displayed. The option argument can be a
           single option or multiple options separated by commas.  Alternatively the -nameopt switch may be used
           more than once to set multiple options. See the x509(1) manual page for details.

       -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 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.

       -no-CAfile
           Do not load the trusted CA certificates from the default file location

       -no-CApath
           Do not load the trusted CA certificates from the default directory location

       -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.

       -ssl3
           This option disables the use of SSL version 3. By default the initial handshake uses a method which
           should be compatible with all servers and permit them to use SSL v3 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.

           Note that this option may not be available, depending on how OpenSSL was built.

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

       -cipher cipherlist
           This allows the TLSv1.2 and below cipher list sent by the client to be modified.  This list will be
           combined with any TLSv1.3 ciphersuites that have been configured. Although the server determines
           which cipher suite is used it should take the first supported cipher in the list sent by the client.
           See ciphers(1) for more information.

       -ciphersuites val
           This allows the TLSv1.3 ciphersuites sent by the client to be modified. This list will be combined
           with any TLSv1.2 and below ciphersuites that have been configured. Although the server determines
           which cipher suite is used it should take the first supported cipher in the list sent by the client.
           See ciphers(1) for more information. The format for this list is a simple colon (":") separated list
           of TLSv1.3 ciphersuite names.

       -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 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 and -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.

SEE ALSO

       s_client(1), s_server(1), ciphers(1)

COPYRIGHT

       Copyright 2004-2019 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the OpenSSL license (the "License").  You may not use this file except in compliance with
       the License.  You can obtain a copy in the file LICENSE in the source distribution or at
       <https://www.openssl.org/source/license.html>.