Restore -no_comp switch for backwards compatible behaviour

[openssl.git] / doc / apps / s_client.pod

diff --git a/doc/apps/s_client.pod b/doc/apps/s_client.pod
index 85e5b9cecb016a1eda145501f04460ddb4e0aae0..e9f3280e3ee542ead108ea69cb7e2dc39cdb30c4 100644 (file)
--- a/doc/apps/s_client.pod
+++ b/doc/apps/s_client.pod
@@ -9,7 +9,10 @@ s_client - SSL/TLS client program
 
 B<openssl> B<s_client>
 [B<-connect host:port>]
 
 B<openssl> B<s_client>
 [B<-connect host:port>]

+[B<-proxy host:port>]
+[B<-servername name>]

 [B<-verify depth>]
 [B<-verify depth>]

+[B<-verify_return_error>]

 [B<-cert filename>]
 [B<-certform DER|PEM>]
 [B<-key filename>]
 [B<-cert filename>]
 [B<-certform DER|PEM>]
 [B<-key filename>]


@@ -17,8 +20,38 @@ B<openssl> B<s_client>
 [B<-pass arg>]
 [B<-CApath directory>]
 [B<-CAfile filename>]
 [B<-pass arg>]
 [B<-CApath directory>]
 [B<-CAfile filename>]

+[B<-no-CAfile>]
+[B<-no-CApath>]
+[B<-dane_tlsa_domain domain>]
+[B<-dane_tlsa_rrdata rrdata>]
+[B<-attime timestamp>]
+[B<-check_ss_sig>]
+[B<-crl_check>]
+[B<-crl_check_all>]
+[B<-explicit_policy>]
+[B<-extended_crl>]
+[B<-ignore_critical>]
+[B<-inhibit_any>]
+[B<-inhibit_map>]
+[B<-issuer_checks>]
+[B<-partial_chain>]
+[B<-policy arg>]
+[B<-policy_check>]
+[B<-policy_print>]
+[B<-purpose purpose>]
+[B<-suiteB_128>]
+[B<-suiteB_128_only>]
+[B<-suiteB_192>]
+[B<-trusted_first>]
+[B<-no_alt_chains>]
+[B<-use_deltas>]
+[B<-verify_depth num>]
+[B<-verify_email email>]
+[B<-verify_hostname hostname>]
+[B<-verify_ip ip>]
+[B<-verify_name name>]
+[B<-x509_strict>]

 [B<-reconnect>]
 [B<-reconnect>]

-[B<-pause>]

 [B<-showcerts>]
 [B<-debug>]
 [B<-msg>]
 [B<-showcerts>]
 [B<-debug>]
 [B<-msg>]


@@ -27,15 +60,21 @@ B<openssl> B<s_client>
 [B<-nbio>]
 [B<-crlf>]
 [B<-ign_eof>]
 [B<-nbio>]
 [B<-crlf>]
 [B<-ign_eof>]

+[B<-no_ign_eof>]

 [B<-quiet>]
 [B<-quiet>]

-[B<-ssl2>]

 [B<-ssl3>]
 [B<-tls1>]
 [B<-ssl3>]
 [B<-tls1>]

-[B<-no_ssl2>]

 [B<-no_ssl3>]
 [B<-no_tls1>]
 [B<-no_ssl3>]
 [B<-no_tls1>]

+[B<-no_tls1_1>]
+[B<-no_tls1_2>]
+[B<-fallback_scsv>]
+[B<-async>]

 [B<-bugs>]
 [B<-bugs>]

+[B<-comp>]
+[B<-no_comp>]

 [B<-cipher cipherlist>]
 [B<-cipher cipherlist>]

+[B<-serverpref>]

 [B<-starttls protocol>]
 [B<-xmpphost hostname>]
 [B<-engine id>]
 [B<-starttls protocol>]
 [B<-xmpphost hostname>]
 [B<-engine id>]


@@ -45,8 +84,8 @@ B<openssl> B<s_client>
 [B<-sess_in filename>]
 [B<-rand file(s)>]
 [B<-serverinfo types>]
 [B<-sess_in filename>]
 [B<-rand file(s)>]
 [B<-serverinfo types>]

-[B<-auth>]
-[B<-auth_require_reneg>]
+[B<-status>]
+[B<-nextprotoneg protocols>]

 
 =head1 DESCRIPTION
 
 
 =head1 DESCRIPTION
 


@@ -68,6 +107,16 @@ manual page.
 This specifies the host and optional port to connect to. If not specified
 then an attempt is made to connect to the local host on port 4433.
 
 This specifies the host and optional port to connect to. If not specified
 then an attempt is made to connect to the local host on port 4433.
 

+=item B<-proxy host:port>
+
+When used with the B<-connect> flag, the program uses the host and port
+specified with this flag and issues an HTTP CONNECT command to connect
+to the desired server.
+
+=item B<-servername name>
+
+Set the TLS SNI (Server Name Indication) extension in the ClientHello message.
+

 =item B<-cert certname>
 
 The certificate to use, if one is requested by the server. The default is
 =item B<-cert certname>
 
 The certificate to use, if one is requested by the server. The default is


@@ -89,7 +138,7 @@ The private format to use: DER or PEM. PEM is the default.
 =item B<-pass arg>
 
 the private key password source. For more information about the format of B<arg>
 =item B<-pass arg>
 
 the private key password source. For more information about the format of B<arg>

-see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)|openssl(1)>.
+see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)>.

 
 =item B<-verify depth>
 
 
 =item B<-verify depth>
 


@@ -99,6 +148,11 @@ 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.
 
 with a certificate chain can be seen. As a side effect the connection
 will never fail due to a server certificate verify failure.
 

+=item B<-verify_return_error>
+
+Return verification errors instead of continuing. This will typically
+abort the handshake with a fatal error.
+

 =item B<-CApath directory>
 
 The directory to use for server certificate verification. This directory
 =item B<-CApath directory>
 
 The directory to use for server certificate verification. This directory


@@ -110,20 +164,69 @@ also used when building the client certificate chain.
 A file containing trusted certificates to use during server authentication
 and to use when attempting to build the client certificate chain.
 
 A file containing trusted certificates to use during server authentication
 and to use when attempting to build the client certificate chain.
 

-=item B<-purpose, -ignore_critical, -issuer_checks, -crl_check, -crl_check_all, -policy_check, -extended_crl, -x509_strict, -policy -check_ss_sig>
-
-Set various certificate chain valiadition option. See the
-L<B<verify>|verify(1)> manual page for details.
+=item B<-no-CAfile>
+
+Do not load the trusted CA certificates from the default file location
+
+=item B<-no-CApath>
+
+Do not load the trusted CA certificates from the default directory location
+
+=item B<-dane_tlsa_domain domain>
+
+Enable RFC6698/RFC7671 DANE TLSA authentication and specify the
+TLSA base domain which becomes the default SNI hint and the primary
+reference identifier for hostname checks.  This must be used in
+combination with at least one instance of the B<-dane_tlsa_rrdata>
+option below.
+
+When DANE authentication succeeds, the diagnostic output will include
+the lowest (closest to 0) depth at which a TLSA record authenticated
+a chain certificate.  When that TLSA record is a "2 1 0" trust
+anchor public key that signed (rather than matched) the top-most
+certificate of the chain, the result is reported as "TA public key
+verified".  Otherwise, either the TLSA record "matched TA certificate"
+at a positive depth or else "matched EE certificate" at depth 0.
+
+=item B<-dane_tlsa_rrdata rrdata>
+
+Use one or more times to specify the RRDATA fields of the DANE TLSA
+RRset associated with the target service.  The B<rrdata> value is
+specied in "presentation form", that is four whitespace separated
+fields that specify the usage, selector, matching type and associated
+data, with the last of these encoded in hexadecimal.  Optional
+whitespace is ignored in the associated data field.  For example:
+
+  $ openssl s_client -starttls smtp -connect smtp.example.com:25 \
+    -dane_tlsa_domain smtp.example.com \
+    -dane_tlsa_rrdata "2 1 1
+      B111DD8A1C2091A89BD4FD60C57F0716CCE50FEEFF8137CDBEE0326E 02CF362B" \
+    -dane_tlsa_rrdata "2 1 1
+      60B87575447DCBA2A36B7D11AC09FB24A9DB406FEE12D2CC90180517 616E8A18"
+  CONNECTED(00000003)
+  ...
+  DANE TLSA 2 1 1 matched TA certificate at depth 1
+  Verified peername: smtp.example.com
+  ...
+      Verify return code: 0 (ok)
+  ...
+
+=item B<-attime>, B<-check_ss_sig>, B<-crl_check>, B<-crl_check_all>,
+B<explicit_policy>, B<-extended_crl>, B<-ignore_critical>, B<-inhibit_any>,
+B<-inhibit_map>, B<-issuer_checks>, B<-partial_chain>, B<-policy>,
+B<-policy_check>, B<-policy_print>, B<-purpose>, B<-suiteB_128>,
+B<-suiteB_128_only>, B<-suiteB_192>, B<-trusted_first>, B<-no_alt_chains>,
+B<-use_deltas>, B<-verify_depth>, B<-verify_email>, B<-verify_hostname>,
+B<-verify_ip>, B<-verify_name>, B<-x509_strict>
+
+Set various certificate chain validation options. See the
+L<verify(1)> manual page for details.

 
 =item B<-reconnect>
 
 reconnects to the same server 5 times using the same session ID, this can
 be used as a test that session caching is working.
 
 
 =item B<-reconnect>
 
 reconnects to the same server 5 times using the same session ID, this can
 be used as a test that session caching is working.
 

-=item B<-pause>
-
-pauses 1 second between each read and write call.
-

 =item B<-showcerts>
 
 display the whole server certificate chain: normally only the server
 =item B<-showcerts>
 
 display the whole server certificate chain: normally only the server


@@ -184,6 +287,11 @@ input.
 inhibit printing of session and certificate information.  This implicitly
 turns on B<-ign_eof> as well.
 
 inhibit printing of session and certificate information.  This implicitly
 turns on B<-ign_eof> as well.
 

+=item B<-no_ign_eof>
+
+shut down the connection when end of file is reached in the input.
+Can be used to override the implicit B<-ign_eof> after B<-quiet>.
+

 =item B<-psk_identity identity>
 
 Use the PSK identity B<identity> when using a PSK cipher suite.
 =item B<-psk_identity identity>
 
 Use the PSK identity B<identity> when using a PSK cipher suite.


@@ -194,22 +302,45 @@ Use the PSK key B<key> when using a PSK cipher suite. The key is
 given as a hexadecimal number without leading 0x, for example -psk
 1a2b3c4d.
 
 given as a hexadecimal number without leading 0x, for example -psk
 1a2b3c4d.
 

-=item B<-ssl2>, B<-ssl3>, B<-tls1>, B<-no_ssl2>, B<-no_ssl3>, B<-no_tls1>
+=item B<-ssl3>, B<-tls1>, B<-no_ssl3>, B<-no_tls1>, B<-no_tls1_1>, B<-no_tls1_2>

 
 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
 
 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.
+servers and permit them to use SSL v3 or TLS as appropriate.

 
 

-Unfortunately there are a lot of ancient and broken servers in use which
+Unfortunately there are still ancient and broken servers in use which

 cannot handle this technique and will fail to connect. Some servers only
 cannot handle this technique and will fail to connect. Some servers only

-work if TLS is turned off with the B<-no_tls> option others will only
-support SSL v2 and may need the B<-ssl2> option.
+work if TLS is turned off.
+
+=item B<-fallback_scsv>
+
+Send TLS_FALLBACK_SCSV in the ClientHello.
+
+=item B<-async>
+
+switch on asynchronous mode. Cryptographic operations will be performed
+asynchronously. This will only have an effect if an asynchronous capable engine
+is also used via the B<-engine> option. For test purposes the dummy async engine
+(dasync) can be used (if available).

 
 =item B<-bugs>
 
 there are several known bug in SSL and TLS implementations. Adding this
 option enables various workarounds.
 
 
 =item B<-bugs>
 
 there are several known bug in SSL and TLS implementations. Adding this
 option enables various workarounds.
 

+=item B<-comp>
+
+Enables support for SSL/TLS compression.
+This option was introduced in OpenSSL 1.1.0.
+TLS compression is not recommended and is off by default as of
+OpenSSL 1.1.0.
+
+=item B<-no_comp>
+
+Disables support for SSL/TLS compression.
+TLS compression is not recommended and is off by default as of
+OpenSSL 1.1.0.
+

 =item B<-brief>
 
 only provide a brief summary of connection parameters instead of the
 =item B<-brief>
 
 only provide a brief summary of connection parameters instead of the


@@ -226,12 +357,13 @@ command for more information.
 
 send the protocol-specific message(s) to switch to TLS for communication.
 B<protocol> is a keyword for the intended protocol.  Currently, the only
 
 send the protocol-specific message(s) to switch to TLS for communication.
 B<protocol> is a keyword for the intended protocol.  Currently, the only

-supported keywords are "smtp", "pop3", "imap", "ftp" and "xmpp".
+supported keywords are "smtp", "pop3", "imap", "ftp", "xmpp", "xmpp-server",
+and "irc."

 
 =item B<-xmpphost hostname>
 
 
 =item B<-xmpphost hostname>
 

-This option, when used with "-starttls xmpp", specifies the host for the
-"to" attribute of the stream element.
+This option, when used with "-starttls xmpp" or "-starttls xmpp-server",
+specifies the host for the "to" attribute of the stream element.

 If this option is not specified, then the host specified with "-connect"
 will be used.
 
 If this option is not specified, then the host specified with "-connect"
 will be used.
 


@@ -262,7 +394,7 @@ for all available algorithms.
 =item B<-rand file(s)>
 
 a file or files containing random data used to seed the random number
 =item B<-rand file(s)>
 
 a file or files containing random data used to seed the random number

-generator, or an EGD socket (see L<RAND_egd(3)|RAND_egd(3)>).
+generator, or an EGD socket (see L<RAND_egd(3)>).

 Multiple files can be specified separated by a OS-dependent character.
 The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for
 all others.
 Multiple files can be specified separated by a OS-dependent character.
 The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for
 all others.


@@ -274,14 +406,21 @@ a list of comma-separated TLS Extension Types (numbers between 0 and
 The server's response (if any) will be encoded and displayed as a PEM
 file.
 
 The server's response (if any) will be encoded and displayed as a PEM
 file.
 

-=item B<-auth>
+=item B<-status>

 
 

-send RFC 5878 client and server authorization extensions in the Client Hello as well as
-supplemental data if the server also sent the authorization extensions in the Server Hello.
+sends a certificate status request to the server (OCSP stapling). The server
+response (if any) is printed out.

 
 

-=item B<-auth_require_reneg>
+=item B<-nextprotoneg protocols>

 
 

-only send RFC 5878 client and server authorization extensions during renegotiation.
+enable Next Protocol Negotiation TLS extension and provide a list of
+comma-separated protocol names that the client should advertise
+support for. The list should contain most wanted protocols first.
+Protocol names are printable ASCII strings, for example "http/1.1" or
+"spdy/3".
+Empty list of protocols is treated specially and will cause the client to
+advertise support for the TLS extension but disconnect just after
+receiving ServerHello with a list of server supported protocols.

 
 =back
 
 
 =back
 


@@ -305,8 +444,8 @@ would typically be used (https uses port 443). If the connection succeeds
 then an HTTP command can be given such as "GET /" to retrieve a web page.
 
 If the handshake fails then there are several possible causes, if it is
 then an HTTP command can be given such as "GET /" to retrieve a web page.
 
 If the handshake fails then there are several possible causes, if it is

-nothing obvious like no client certificate then the B<-bugs>, B<-ssl2>,
-B<-ssl3>, B<-tls1>, B<-no_ssl2>, B<-no_ssl3>, B<-no_tls1> options can be tried
+nothing obvious like no client certificate then the B<-bugs>,
+B<-ssl3>, B<-tls1>, B<-no_ssl3>, B<-no_tls1> options can be tried

 in case it is a buggy server. In particular you should play with these
 options B<before> submitting a bug report to an OpenSSL mailing list.
 
 in case it is a buggy server. In particular you should play with these
 options B<before> submitting a bug report to an OpenSSL mailing list.
 


@@ -328,9 +467,12 @@ 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.
 
 If there are problems verifying a server certificate then the
 B<-showcerts> option can be used to show the whole chain.
 

-Since the SSLv23 client hello cannot include compression methods or extensions
-these will only be supported if its use is disabled, for example by using the
-B<-no_sslv2> option.
+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
+accept any certificate chain (trusted or not) sent by the peer. None test
+applications should B<not> do this as it makes them vulnerable to a MITM
+attack. This behaviour can be changed by with the B<-verify_return_error>
+option: any verify errors are then returned aborting the handshake.

 
 =head1 BUGS
 
 
 =head1 BUGS
 


@@ -339,14 +481,15 @@ the techniques used are rather old, the C source of s_client is rather
 hard to read and not a model of how things should be done. A typical
 SSL client program would be much simpler.
 
 hard to read and not a model of how things should be done. A typical
 SSL client program would be much simpler.
 

-The B<-verify> option should really exit if the server verification
-fails.
-

 The B<-prexit> option is a bit of a hack. We should really report
 information whenever a session is renegotiated.
 
 =head1 SEE ALSO
 
 The B<-prexit> option is a bit of a hack. We should really report
 information whenever a session is renegotiated.
 
 =head1 SEE ALSO
 

-L<sess_id(1)|sess_id(1)>, L<s_server(1)|s_server(1)>, L<ciphers(1)|ciphers(1)>
+L<sess_id(1)>, L<s_server(1)>, L<ciphers(1)>
+
+=head1 HISTORY
+
+The -no_alt_chains options was first added to OpenSSL 1.1.0.

 
 =cut
 
 =cut