S_TIME 1 2004-03-19 0.9.9-dev OpenSSL

NAME

s_time - SSL/TLS performance timing program

LIBRARY

libcrypto, -lcrypto

SYNOPSIS

ooppeennssssll ss__ttiimmee [--ccoonnnneecctt hhoosstt::ppoorrtt] [--wwwwww ppaaggee] [--cceerrtt ffiilleennaammee] [--kkeeyy ffiilleennaammee] [--CCAAppaatthh ddiirreeccttoorryy] [--CCAAffiillee ffiilleennaammee] [--rreeuussee] [--nneeww] [--vveerriiffyy ddeepptthh] [--nnbbiioo] [--ttiimmee sseeccoonnddss] [--ssssll22] [--ssssll33] [--bbuuggss] [--cciipphheerr cciipphheerrlliisstt]

DESCRIPTION

The ss__cclliieenntt 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

--ccoonnnneecctt hhoosstt::ppoorrtt This specifies the host and optional port to connect to.
--wwwwww ppaaggee 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 ss__ttiimmee will only perform the handshake to establish SSL connections but not transfer any payload data.
--cceerrtt cceerrttnnaammee 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.
--kkeeyy kkeeyyffiillee The private key to use. If not specified then the certificate file will
be used. The file is in PEM format.
--vveerriiffyy ddeepptthh 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.
--CCAAppaatthh ddiirreeccttoorryy The directory to use for server certificate verification. This directory
must be in "hash format", see vveerriiffyy for more information. These are also used when building the client certificate chain.
--CCAAffiillee ffiillee A file containing trusted certificates to use during server authentication
and to use when attempting to build the client certificate chain.
--nneeww performs the timing test using a new session ID for each connection.
If neither --nneeww nor --rreeuussee are specified, they are both on by default and executed in sequence.
--rreeuussee performs the timing test using the same session ID; this can be used as a test
that session caching is working. If neither --nneeww nor --rreeuussee are specified, they are both on by default and executed in sequence.
--nnbbiioo turns on non-blocking I/O.
--ssssll22, --ssssll33 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 _o_p_e_n_s_s_l___s___c_l_i_e_n_t(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 --ssssll33 option; others will only support SSL v2 and may need the --ssssll22 option.
--bbuuggss there are several known bug in SSL and TLS implementations. Adding this
option enables various workarounds.
--cciipphheerr cciipphheerrlliisstt 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 _o_p_e_n_s_s_l___c_i_p_h_e_r_s(1) command for more information.
--ttiimmee lleennggtthh specifies how long (in seconds) ss__ttiimmee should establish connections and
optionally transfer payload data from a server. Server and client performance and the link speed determine how many connections ss__ttiimmee can establish.

NOTES

ss__cclliieenntt 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 _o_p_e_n_s_s_l___c_i_p_h_e_r_s(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 --bbuuggss, --ssssll22, --ssssll33 options can be tried in case it is a buggy server. In particular you should play with these options bbeeffoorree 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 _o_p_e_n_s_s_l___s___c_l_i_e_n_t(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 --pprreexxiitt option of _o_p_e_n_s_s_l___s___c_l_i_e_n_t(1) and send an HTTP request for an appropriate page.

If a certificate is specified on the command line using the --cceerrtt 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 _o_p_e_n_s_s_l___s___c_l_i_e_n_t(1) program to turn protocols on and off, you may not be able to measure the performance of all protocols with all servers.

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

SEE ALSO

_o_p_e_n_s_s_l___s___c_l_i_e_n_t(1), _o_p_e_n_s_s_l___s___s_e_r_v_e_r(1), _o_p_e_n_s_s_l___c_i_p_h_e_r_s(1)