B<openssl> B<s_client>
[B<-help>]
[B<-connect host:port>]
+[B<-bind host:port>]
[B<-proxy host:port>]
[B<-unix path>]
[B<-4>]
[B<-certform DER|PEM>]
[B<-key filename>]
[B<-keyform DER|PEM>]
+[B<-cert_chain filename>]
+[B<-build_chain>]
+[B<-xkey>]
+[B<-xcert>]
+[B<-xchain>]
+[B<-xchain_build>]
+[B<-xcertform PEM|DER>]
+[B<-xkeyform PEM|DER>]
[B<-pass arg>]
[B<-CApath directory>]
[B<-CAfile filename>]
+[B<-chainCApath directory>]
+[B<-chainCAfile filename>]
[B<-no-CAfile>]
[B<-no-CApath>]
[B<-requestCAfile filename>]
[B<-verify_hostname hostname>]
[B<-verify_ip ip>]
[B<-verify_name name>]
+[B<-build_chain>]
[B<-x509_strict>]
[B<-reconnect>]
[B<-showcerts>]
[B<-crlf>]
[B<-ign_eof>]
[B<-no_ign_eof>]
+[B<-psk_identity identity>]
+[B<-psk key>]
+[B<-psk_session file>]
[B<-quiet>]
[B<-ssl3>]
[B<-tls1>]
[B<-sigalgs sigalglist>]
[B<-curves curvelist>]
[B<-cipher cipherlist>]
+[B<-ciphersuites val>]
[B<-serverpref>]
[B<-starttls protocol>]
[B<-xmpphost hostname>]
[B<-ctlogfile>]
[B<-keylogfile file>]
[B<-early_data file>]
-[B<-force_pha>]
+[B<-enable_pha>]
[B<target>]
=head1 DESCRIPTION
This specifies the host and optional port to connect to. It is possible to
select the host and port using the optional target positional argument instead.
-If neither this nor the target positonal argument are specified then an attempt
+If neither this nor the target positional argument are specified then an attempt
is made to connect to the local host on port 4433.
+=item B<-bind host:port>]
+
+This specifies the host address and or port to bind as the source for the
+connection. For Unix-domain sockets the port is ignored and the host is
+used as the source socket address.
+
=item B<-proxy host:port>
When used with the B<-connect> flag, the program uses the host and port
The private format to use: DER or PEM. PEM is the default.
+=item B<-cert_chain>
+
+A file containing trusted certificates to use when attempting to build the
+client/server certificate chain related to the certificate specified via the
+B<-cert> option.
+
+=item B<-build_chain>
+
+Specify whether the application should build the certificate chain to be
+provided to the server.
+
+=item B<-xkey infile>, B<-xcert infile>, B<-xchain>
+
+Specify an extra certificate, private key and certificate chain. These behave
+in the same manner as the B<-cert>, B<-key> and B<-cert_chain> options. When
+specified, the callback returning the first valid chain will be in use by the
+client.
+
+=item B<-xchain_build>
+
+Specify whether the application should build the certificate chain to be
+provided to the server for the extra certificates provided via B<-xkey infile>,
+B<-xcert infile>, B<-xchain> options.
+
+=item B<-xcertform PEM|DER>, B<-xkeyform PEM|DER>
+
+Extra certificate and private key format respectively.
+
=item B<-pass arg>
the private key password source. For more information about the format of B<arg>
=item B<-CApath directory>
The directory to use for server certificate verification. This directory
-must be in "hash format", see B<verify> for more information. These are
+must be in "hash format", see L<verify(1)> for more information. These are
also used when building the client certificate chain.
=item B<-CAfile file>
A file containing trusted certificates to use during server authentication
and to use when attempting to build the client certificate chain.
+=item B<-chainCApath directory>
+
+The directory to use for building the chain provided to the server. This
+directory must be in "hash format", see L<verify(1)> for more information.
+
+=item B<-chainCAfile file>
+
+A file containing trusted certificates to use when attempting to build the
+client certificate chain.
+
=item B<-no-CAfile>
Do not load the trusted CA certificates from the default file location
=item B<-showcerts>
-Display the whole server certificate chain: normally only the server
-certificate itself is displayed.
+Displays the server certificate list as sent by the server: it only consists of
+certificates the server has sent (in the order the server has sent them). It is
+B<not> a verified chain.
=item B<-prexit>
1a2b3c4d.
This option must be provided in order to use a PSK cipher.
+=item B<-psk_session file>
+
+Use the pem encoded SSL_SESSION data stored in B<file> as the basis of a PSK.
+Note that this will only work if TLSv1.3 is negotiated.
+
=item B<-ssl3>, B<-tls1>, B<-tls1_1>, B<-tls1_2>, B<-tls1_3>, B<-no_ssl3>, B<-no_tls1>, B<-no_tls1_1>, B<-no_tls1_2>, B<-no_tls1_3>
These options require or disable the use of the specified SSL or TLS protocols.
version.
When a specific TLS version is required, only that version will be offered to
and accepted from the server.
+Note that not all protocols and flags may be available, depending on how
+OpenSSL was built.
=item B<-dtls>, B<-dtls1>, B<-dtls1_2>
=item B<-curves curvelist>
Specifies the list of supported curves to be sent by the client. The curve is
-is ultimately selected by the server. For a list of all curves, use:
+ultimately selected by the server. For a list of all curves, use:
$ openssl ecparam -list_curves
=item B<-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 B<ciphers>
-command for more information.
+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 ciphersuite is used it should
+take the first supported cipher in the list sent by the client. See the
+B<ciphers> command for more information.
+
+=item B<-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 the
+B<ciphers> command for more information. The format for this list is a simple
+colon (":") separated list of TLSv1.3 ciphersuite names.
=item B<-starttls protocol>
to the server. This will only work with resumed sessions that support early
data and when the server accepts the early data.
-=item B<-force_pha>
+=item B<-enable_pha>
-For TLSv1.3 only, always send the Post-Handshake Authentication extension,
-whether or not a certificate has been provided via B<-cert>.
+For TLSv1.3 only, send the Post-Handshake Authentication extension. This will
+happen whether or not a certificate has been provided via B<-cert>.
=item B<[target]>
If a connection is established with an SSL server then any data received
from the server is displayed and any key presses will be sent to the
-server. When used interactively (which means neither B<-quiet> nor B<-ign_eof>
-have been given), the session will be renegotiated if the line begins with an
-B<R>, and if the line begins with a B<Q> or if end of file is reached, the
-connection will be closed down.
+server. If end of file is reached then the connection will be closed down. When
+used interactively (which means neither B<-quiet> nor B<-ign_eof> have been
+given), then certain commands are also recognized which perform special
+operations. These commands are a letter which must appear at the start of a
+line. They are listed below.
+
+=over 4
+
+=item B<Q>
+
+End the current SSL connection and exit.
+
+=item B<R>
+
+Renegotiate the SSL session (TLSv1.2 and below only).
+
+=item B<B>
+
+Send a heartbeat message to the server (DTLS only)
+
+=item B<k>
+
+Send a key update message to the server (TLSv1.3 only)
+
+=item B<K>
+
+Send a key update message to the server and request one back (TLSv1.3 only)
+
+=back
=head1 NOTES
on the command line is no guarantee that the certificate works.
If there are problems verifying a server certificate then the
-B<-showcerts> option can be used to show the whole chain.
+B<-showcerts> option can be used to show all the certificates sent by the
+server.
The B<s_client> utility is a test tool and is designed to continue the
handshake after any certificate verification errors. As a result it will
attack. This behaviour can be changed by with the B<-verify_return_error>
option: any verify errors are then returned aborting the handshake.
+The B<-bind> option may be useful if the server or a firewall requires
+connections to come from some particular address and or port.
+
=head1 BUGS
Because this program has a lot of options and also because some of the
=head1 SEE ALSO
L<SSL_CONF_cmd(3)>, L<sess_id(1)>, L<s_server(1)>, L<ciphers(1)>,
-L<SSL_CTX_set_max_send_fragment(3)>, L<SSL_CTX_set_split_send_fragment(3)>
+L<SSL_CTX_set_max_send_fragment(3)>, L<SSL_CTX_set_split_send_fragment(3)>,
L<SSL_CTX_set_max_pipelines(3)>
=head1 HISTORY
projects / openssl.git / blobdiff