6 s_time - SSL/TLS performance timing program
12 [B<-connect host:port>]
16 [B<-CApath directory>]
27 [B<-cipher cipherlist>]
31 The B<s_time> command implements a generic SSL/TLS client which connects to a
32 remote host using SSL/TLS. It can request a page from the server and includes
33 the time to transfer the payload data in its timing measurements. It measures
34 the number of connections within a given timeframe, the amount of data
35 transferred (if any), and calculates the average time spent for one connection.
43 Print out a usage message.
45 =item B<-connect host:port>
47 This specifies the host and optional port to connect to.
51 This specifies the page to GET from the server. A value of '/' gets the
52 index.htm[l] page. If this parameter is not specified, then B<s_time> will only
53 perform the handshake to establish SSL connections but not transfer any
56 =item B<-cert certname>
58 The certificate to use, if one is requested by the server. The default is
59 not to use a certificate. The file is in PEM format.
63 The private key to use. If not specified then the certificate file will
64 be used. The file is in PEM format.
66 =item B<-verify depth>
68 The verify depth to use. This specifies the maximum length of the
69 server certificate chain and turns on server certificate verification.
70 Currently the verify operation continues after errors so all the problems
71 with a certificate chain can be seen. As a side effect the connection
72 will never fail due to a server certificate verify failure.
74 =item B<-CApath directory>
76 The directory to use for server certificate verification. This directory
77 must be in "hash format", see B<verify> for more information. These are
78 also used when building the client certificate chain.
82 A file containing trusted certificates to use during server authentication
83 and to use when attempting to build the client certificate chain.
87 Do not load the trusted CA certificates from the default file location
91 Do not load the trusted CA certificates from the default directory location
95 performs the timing test using a new session ID for each connection.
96 If neither B<-new> nor B<-reuse> are specified, they are both on by default
97 and executed in sequence.
101 performs the timing test using the same session ID; this can be used as a test
102 that session caching is working. If neither B<-new> nor B<-reuse> are
103 specified, they are both on by default and executed in sequence.
107 turns on non-blocking I/O.
111 these options disable the use of certain SSL or TLS protocols. By default
112 the initial handshake uses a method which should be compatible with all
113 servers and permit them to use SSL v3 or TLS as appropriate.
114 The timing program is not as rich in options to turn protocols on and off as
115 the L<s_client(1)> program and may not connect to all servers.
117 Unfortunately there are a lot of ancient and broken servers in use which
118 cannot handle this technique and will fail to connect. Some servers only
119 work if TLS is turned off with the B<-ssl3> option.
123 there are several known bug in SSL and TLS implementations. Adding this
124 option enables various workarounds.
126 =item B<-cipher cipherlist>
128 this allows the cipher list sent by the client to be modified. Although
129 the server determines which cipher suite is used it should take the first
130 supported cipher in the list sent by the client.
131 See the L<ciphers(1)> command for more information.
133 =item B<-time length>
135 specifies how long (in seconds) B<s_time> should establish connections and
136 optionally transfer payload data from a server. Server and client performance
137 and the link speed determine how many connections B<s_time> can establish.
143 B<s_time> can be used to measure the performance of an SSL connection.
144 To connect to an SSL HTTP server and get the default page the command
146 openssl s_time -connect servername:443 -www / -CApath yourdir -CAfile yourfile.pem -cipher commoncipher [-ssl3]
148 would typically be used (https uses port 443). 'commoncipher' is a cipher to
149 which both client and server can agree, see the L<ciphers(1)> command
152 If the handshake fails then there are several possible causes, if it is
153 nothing obvious like no client certificate then the B<-bugs> and
154 B<-ssl3> options can be tried
155 in case it is a buggy server. In particular you should play with these
156 options B<before> submitting a bug report to an OpenSSL mailing list.
158 A frequent problem when attempting to get client certificates working
159 is that a web client complains it has no certificates or gives an empty
160 list to choose from. This is normally because the server is not sending
161 the clients certificate authority in its "acceptable CA list" when it
162 requests a certificate. By using L<s_client(1)> the CA list can be
163 viewed and checked. However some servers only request client authentication
164 after a specific URL is requested. To obtain the list in this case it
165 is necessary to use the B<-prexit> option of L<s_client(1)> and
166 send an HTTP request for an appropriate page.
168 If a certificate is specified on the command line using the B<-cert>
169 option it will not be used unless the server specifically requests
170 a client certificate. Therefor merely including a client certificate
171 on the command line is no guarantee that the certificate works.
175 Because this program does not have all the options of the
176 L<s_client(1)> program to turn protocols on and off, you may not be
177 able to measure the performance of all protocols with all servers.
179 The B<-verify> option should really exit if the server verification
184 L<s_client(1)>, L<s_server(1)>, L<ciphers(1)>