OPENSSL-S_TIME(1SSL) OpenSSL OPENSSL-S_TIME(1SSL)
NAME
openssl-s_time - SSL/TLS performance timing program
SYNOPSIS
openssl s_time [-help] [-connect host:port] [-www page] [-cert filename]
[-key filename] [-reuse] [-new] [-verify depth] [-time seconds] [-ssl3]
[-tls1] [-tls1_1] [-tls1_2] [-tls1_3] [-bugs] [-cipher cipherlist]
[-ciphersuites val] [-nameopt option] [-cafile file] [-CAfile file]
[-no-CAfile] [-CApath dir] [-no-CApath] [-CAstore uri] [-no-CAstore]
[-provider name] [-provider-path path] [-provparam [name:]key=value]
[-propquery propq]
DESCRIPTION
This 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. If the
host string is an IPv6 address, it must be enclosed in "[" and "]".
-www page
This specifies the page to GET from the server. A value of '/' gets
the index.html page. If this parameter is not specified, then this
command 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.
-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.
-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
openssl-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
openssl-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) this command should establish
connections and optionally transfer payload data from a server.
Server and client performance and the link speed determine how many
connections it can establish.
-nameopt option
This specifies how the subject or issuer names are displayed. See
openssl-namedisplay-options(1) for details.
-CAfile file, -no-CAfile, -CApath dir, -no-CApath, -CAstore uri,
-no-CAstore
See "Trusted Certificate Options" in openssl-verification-options(1)
for details.
-provider name
-provider-path path
-provparam [name:]key=value
-propquery propq
See "Provider Options" in openssl(1), provider(7), and property(7).
-cafile file
This is an obsolete synonym for -CAfile.
-ssl3, -tls1, -tls1_1, -tls1_2, -tls1_3
See "TLS Version Options" in openssl(1).
NOTES
This command 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 openssl-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 openssl-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
openssl-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. Therefore, 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
openssl-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.
HISTORY
The -cafile option was deprecated in OpenSSL 3.0.
SEE ALSO
openssl(1), openssl-s_client(1), openssl-s_server(1),
openssl-ciphers(1), ossl_store-file(7)
COPYRIGHT
Copyright 2004-2021 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the Apache License 2.0 (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>.
3.5.4 2025-09-30 OPENSSL-S_TIME(1SSL)
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