X-Git-Url: https://git.openssl.org/gitweb/?a=blobdiff_plain;f=doc%2Fapps%2Fs_client.pod;h=04982e64141753858feaae31aaf780da6760f966;hb=035014cd22c502bca93c73e6475da73ee31f1078;hp=afdc3f7df2f772075da9d5d85666a77c317e0e55;hpb=85c6749216f47bcefc916d4b0331794dac0a5db7;p=openssl.git diff --git a/doc/apps/s_client.pod b/doc/apps/s_client.pod index afdc3f7df2..04982e6414 100644 --- a/doc/apps/s_client.pod +++ b/doc/apps/s_client.pod @@ -9,7 +9,10 @@ s_client - SSL/TLS client program B B [B<-connect host:port>] +[B<-proxy host:port>] +[B<-servername name>] [B<-verify depth>] +[B<-verify_return_error>] [B<-cert filename>] [B<-certform DER|PEM>] [B<-key filename>] @@ -17,6 +20,33 @@ B B [B<-pass arg>] [B<-CApath directory>] [B<-CAfile filename>] +[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<-pause>] [B<-showcerts>] @@ -27,18 +57,29 @@ B B [B<-nbio>] [B<-crlf>] [B<-ign_eof>] +[B<-no_ign_eof>] [B<-quiet>] -[B<-ssl2>] [B<-ssl3>] [B<-tls1>] -[B<-no_ssl2>] [B<-no_ssl3>] [B<-no_tls1>] +[B<-no_tls1_1>] +[B<-no_tls1_2>] +[B<-fallback_scsv>] [B<-bugs>] [B<-cipher cipherlist>] +[B<-serverpref>] [B<-starttls protocol>] +[B<-xmpphost hostname>] [B<-engine id>] +[B<-tlsextdebug>] +[B<-no_ticket>] +[B<-sess_out filename>] +[B<-sess_in filename>] [B<-rand file(s)>] +[B<-serverinfo types>] +[B<-status>] +[B<-nextprotoneg protocols>] =head1 DESCRIPTION @@ -48,6 +89,11 @@ SSL servers. =head1 OPTIONS +In addition to the options below the B utility also supports the +common and client only options documented in the +in the L +manual page. + =over 4 =item B<-connect host:port> @@ -55,6 +101,16 @@ SSL servers. 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 @@ -76,7 +132,7 @@ 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 -see the B section in L. +see the B section in L. =item B<-verify depth> @@ -86,6 +142,11 @@ 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. +=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 @@ -97,6 +158,17 @@ 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. +=item B<-attime>, B<-check_ss_sig>, B<-crl_check>, B<-crl_check_all>, +B, 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 manual page for details. + =item B<-reconnect> reconnects to the same server 5 times using the same session ID, this can @@ -134,6 +206,15 @@ print extensive debugging information including a hex dump of all traffic. show all protocol messages with hex dump. +=item B<-trace> + +show verbose trace output of protocol messages. OpenSSL needs to be compiled +with B for this option to work. + +=item B<-msgfile> + +file to send output of B<-msg> or B<-trace> to, default standard output. + =item B<-nbio_test> tests non-blocking I/O @@ -157,6 +238,11 @@ input. 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 when using a PSK cipher suite. @@ -167,22 +253,30 @@ Use the PSK key B when using a PSK cipher suite. The key is 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 -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 -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<-bugs> there are several known bug in SSL and TLS implementations. Adding this option enables various workarounds. +=item B<-brief> + +only provide a brief summary of connection parameters instead of the +normal verbose output. + =item B<-cipher cipherlist> this allows the cipher list sent by the client to be modified. Although @@ -194,11 +288,36 @@ command for more information. send the protocol-specific message(s) to switch to TLS for communication. B is a keyword for the intended protocol. Currently, the only -supported keywords are "smtp", "pop3", "imap", and "ftp". +supported keywords are "smtp", "pop3", "imap", "ftp", "xmpp", +and "xmpp-server". + +=item B<-xmpphost hostname> + +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. + +=item B<-tlsextdebug> + +print out a hex dump of any TLS extensions received from the server. + +=item B<-no_ticket> + +disable RFC4507bis session ticket support. + +=item B<-sess_out filename> + +output SSL session to B + +=item B<-sess_in sess.pem> + +load SSL session from B. The client will attempt to resume a +connection from this session. =item B<-engine id> -specifying an engine (by it's unique B string) will cause B +specifying an engine (by its unique B string) will cause B to attempt to obtain a functional reference to the specified engine, thus initialising it if needed. The engine will then be set as the default for all available algorithms. @@ -206,11 +325,34 @@ for all available algorithms. =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). +generator, or an EGD socket (see L). 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. +=item B<-serverinfo types> + +a list of comma-separated TLS Extension Types (numbers between 0 and +65535). Each type will be sent as an empty ClientHello TLS Extension. +The server's response (if any) will be encoded and displayed as a PEM +file. + +=item B<-status> + +sends a certificate status request to the server (OCSP stapling). The server +response (if any) is printed out. + +=item B<-nextprotoneg protocols> + +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 =head1 CONNECTED COMMANDS @@ -233,8 +375,8 @@ 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 -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 submitting a bug report to an OpenSSL mailing list. @@ -256,6 +398,13 @@ 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. +The B 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 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 Because this program has a lot of options and also because some of @@ -263,14 +412,15 @@ 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. -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 -L, L, L +L, L, L + +=head1 HISTORY + +The -no_alt_chains options was first added to OpenSSL 1.1.0. =cut