=head1 SYNOPSIS
B<openssl> B<ca>
+[B<-help>]
[B<-verbose>]
[B<-config filename>]
[B<-name section>]
the key password source. For more information about the format of B<arg>
see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)>.
+=item B<-help>
+
+Print out a usage message.
+
=item B<-verbose>
this prints extra details about the operations being performed.
=head1 SYNOPSIS
B<openssl> B<cms>
+[B<-help>]
[B<-encrypt>]
[B<-decrypt>]
[B<-sign>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-encrypt>
encrypt mail for the given recipient certificates. Input file is the message
=head1 SYNOPSIS
B<openssl> B<crl>
+[B<-help>]
[B<-inform PEM|DER>]
[B<-outform PEM|DER>]
[B<-text>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-inform DER|PEM>
This specifies the input format. B<DER> format is DER encoded CRL
=head1 SYNOPSIS
B<openssl> B<crl2pkcs7>
+[B<-help>]
[B<-inform PEM|DER>]
[B<-outform PEM|DER>]
[B<-in filename>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-inform DER|PEM>
This specifies the CRL input format. B<DER> format is DER encoded CRL
=head1 SYNOPSIS
B<openssl> B<dgst>
+[B<-help>]
[B<-sha|-sha1|-mdc2|-ripemd160|-sha224|-sha256|-sha384|-sha512|-md4|-md5>]
[B<-c>]
[B<-d>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-c>
print out the digest in two digit groups separated by colons, only relevant if
=head1 SYNOPSIS
B<openssl dhparam>
+[B<-help>]
[B<-inform DER|PEM>]
[B<-outform DER|PEM>]
[B<-in> I<filename>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-inform DER|PEM>
This specifies the input format. The B<DER> option uses an ASN1 DER encoded
=head1 SYNOPSIS
B<openssl> B<dsa>
+[B<-help>]
[B<-inform PEM|DER>]
[B<-outform PEM|DER>]
[B<-in filename>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-inform DER|PEM>
This specifies the input format. The B<DER> option with a private key uses
=head1 SYNOPSIS
B<openssl dsaparam>
+[B<-help>]
[B<-inform DER|PEM>]
[B<-outform DER|PEM>]
[B<-in filename>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-inform DER|PEM>
This specifies the input format. The B<DER> option uses an ASN1 DER encoded
=head1 SYNOPSIS
B<openssl> B<ec>
+[B<-help>]
[B<-inform PEM|DER>]
[B<-outform PEM|DER>]
[B<-in filename>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-inform DER|PEM>
This specifies the input format. The B<DER> option with a private key uses
=head1 SYNOPSIS
B<openssl ecparam>
+[B<-help>]
[B<-inform DER|PEM>]
[B<-outform DER|PEM>]
[B<-in filename>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-inform DER|PEM>
This specifies the input format. The B<DER> option uses an ASN.1 DER encoded
=head1 SYNOPSIS
B<openssl enc -ciphername>
+[B<-help>]
[B<-in filename>]
[B<-out filename>]
[B<-pass arg>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-in filename>
the input filename, standard input by default.
=head1 SYNOPSIS
B<openssl> B<gendsa>
+[B<-help>]
[B<-out filename>]
[B<-aes128>]
[B<-aes192>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
+=item B<-out filename>
+
+Output the key to the specified file. If this argument is not specified then
+standard output is used.
+
=item B<-aes128|-aes192|-aes256|-camellia128|-camellia192|-camellia256|-des|-des3|-idea>
These options encrypt the private key with specified
=head1 SYNOPSIS
B<openssl> B<genpkey>
+[B<-help>]
[B<-out filename>]
[B<-outform PEM|DER>]
[B<-pass arg>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-out filename>
-the output filename. If this argument is not specified then standard output is
-used.
+Output the key to the specified file. If this argument is not specified then
+standard output is used.
=item B<-outform DER|PEM>
=head1 SYNOPSIS
B<openssl> B<genrsa>
+[B<-help>]
[B<-out filename>]
[B<-passout arg>]
[B<-aes128>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-out filename>
-the output filename. If this argument is not specified then standard output is
-used.
+Output the key to the specified file. If this argument is not specified then
+standard output is used.
=item B<-passout arg>
=head1 SYNOPSIS
B<openssl> B<nseq>
+[B<-help>]
[B<-in filename>]
[B<-out filename>]
[B<-toseq>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-in filename>
This specifies the input filename to read or standard input if this
=head1 SYNOPSIS
B<openssl> B<ocsp>
+[B<-help>]
[B<-out file>]
[B<-issuer file>]
[B<-cert file>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-out filename>
specify output filename, default is standard output.
=head1 SYNOPSIS
B<openssl passwd>
+[B<-help>]
[B<-crypt>]
[B<-1>]
[B<-apr1>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-crypt>
Use the B<crypt> algorithm (default).
=head1 SYNOPSIS
B<openssl> B<pkcs12>
+[B<-help>]
[B<-export>]
[B<-chain>]
[B<-inkey filename>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-in filename>
This specifies filename of the PKCS#12 file to be parsed. Standard input is used
=head1 SYNOPSIS
B<openssl> B<pkcs7>
+[B<-help>]
[B<-inform PEM|DER>]
[B<-outform PEM|DER>]
[B<-in filename>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-inform DER|PEM>
This specifies the input format. B<DER> format is DER encoded PKCS#7
=head1 SYNOPSIS
B<openssl> B<pkcs8>
+[B<-help>]
[B<-topk8>]
[B<-inform PEM|DER>]
[B<-outform PEM|DER>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-topk8>
Normally a PKCS#8 private key is expected on input and a traditional format
=head1 SYNOPSIS
B<openssl> B<pkey>
+[B<-help>]
[B<-inform PEM|DER>]
[B<-outform PEM|DER>]
[B<-in filename>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-inform DER|PEM>
This specifies the input format DER or PEM.
=head1 SYNOPSIS
B<openssl> B<pkeyparam>
+[B<-help>]
[B<-in filename>]
[B<-out filename>]
[B<-text>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-in filename>
This specifies the input filename to read parameters from or standard input if
=head1 SYNOPSIS
B<openssl> B<pkeyutl>
+[B<-help>]
[B<-in file>]
[B<-out file>]
[B<-sigfile file>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-in filename>
This specifies the input filename to read data from or standard input
=head1 SYNOPSIS
B<openssl rand>
+[B<-help>]
[B<-out> I<file>]
[B<-rand> I<file(s)>]
[B<-base64>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-out> I<file>
Write to I<file> instead of standard output.
B<openssl>
B<rehash>
+B<[-help]>
B<[-old]>
-B<[-h]>
B<[-n]>
B<[-v]>
[ I<directory>...]
=over 4
+=item B<-help>
+
+Display a brief usage message.
+
=item B<-old>
Use old-style hashing (MD5, as opposed to SHA-1) for generating
links to be used for releases before 1.0.0.
Note that current versions will not use the old style.
-=item B<-h>
-
-Display a brief usage message.
-
=item B<-n>
Do not remove existing links.
=head1 SYNOPSIS
B<openssl> B<req>
+[B<-help>]
[B<-inform PEM|DER>]
[B<-outform PEM|DER>]
[B<-in filename>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-inform DER|PEM>
This specifies the input format. The B<DER> option uses an ASN1 DER encoded
=head1 SYNOPSIS
B<openssl> B<rsa>
+[B<-help>]
[B<-inform PEM|NET|DER>]
[B<-outform PEM|NET|DER>]
[B<-in filename>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-inform DER|NET|PEM>
This specifies the input format. The B<DER> option uses an ASN1 DER encoded
=head1 SYNOPSIS
B<openssl> B<rsautl>
+[B<-help>]
[B<-in file>]
[B<-out file>]
[B<-inkey file>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-in filename>
This specifies the input filename to read data from or standard input
=item B<-pubin>
-the input file is an RSA public key.
+the input file is an RSA public key.
=item B<-certin>
=head1 SYNOPSIS
B<openssl> B<s_client>
+[B<-help>]
[B<-connect host:port>]
[B<-proxy host:port>]
[B<-servername name>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-connect host:port>
This specifies the host and optional port to connect to. If not specified
--- /dev/null
+
+=pod
+
+=head1 NAME
+
+s_client - SSL/TLS client program
+
+=head1 SYNOPSIS
+
+B<openssl> B<s_client>
+[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>]
+[B<-keyform DER|PEM>]
+[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<-showcerts>]
+[B<-debug>]
+[B<-msg>]
+[B<-nbio_test>]
+[B<-state>]
+[B<-nbio>]
+[B<-crlf>]
+[B<-ign_eof>]
+[B<-no_ign_eof>]
+[B<-quiet>]
+[B<-ssl3>]
+[B<-tls1>]
+[B<-no_ssl3>]
+[B<-no_tls1>]
+[B<-no_tls1_1>]
+[B<-no_tls1_2>]
+[B<-fallback_scsv>]
+[B<-async>]
+[B<-bugs>]
+[B<-comp>]
+[B<-no_comp>]
+[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
+
+The B<s_client> command implements a generic SSL/TLS client which connects
+to a remote host using SSL/TLS. It is a I<very> useful diagnostic tool for
+SSL servers.
+
+=head1 OPTIONS
+
+In addition to the options below the B<s_client> utility also supports the
+common and client only options documented in the
+in the L<SSL_CONF_cmd(3)|SSL_CONF_cmd(3)/SUPPORTED COMMAND LINE COMMANDS>
+manual page.
+
+=over 4
+
+=item B<-connect host:port>
+
+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
+not to use a certificate.
+
+=item B<-certform format>
+
+The certificate format to use: DER or PEM. PEM is the default.
+
+=item B<-key keyfile>
+
+The private key to use. If not specified then the certificate file will
+be used.
+
+=item B<-keyform format>
+
+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>
+see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)>.
+
+=item B<-verify depth>
+
+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.
+
+=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
+must be in "hash format", see B<verify> 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<-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<-showcerts>
+
+display the whole server certificate chain: normally only the server
+certificate itself is displayed.
+
+=item B<-prexit>
+
+print session information when the program exits. This will always attempt
+to print out information even if the connection fails. Normally information
+will only be printed out once if the connection succeeds. This option is useful
+because the cipher in use may be renegotiated or the connection may fail
+because a client certificate is required or is requested only after an
+attempt is made to access a certain URL. Note: the output produced by this
+option is not always accurate because a connection might never have been
+established.
+
+=item B<-state>
+
+prints out the SSL session states.
+
+=item B<-debug>
+
+print extensive debugging information including a hex dump of all traffic.
+
+=item B<-msg>
+
+show all protocol messages with hex dump.
+
+=item B<-trace>
+
+show verbose trace output of protocol messages. OpenSSL needs to be compiled
+with B<enable-ssl-trace> 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
+
+=item B<-nbio>
+
+turns on non-blocking I/O
+
+=item B<-crlf>
+
+this option translated a line feed from the terminal into CR+LF as required
+by some servers.
+
+=item B<-ign_eof>
+
+inhibit shutting down the connection when end of file is reached in the
+input.
+
+=item B<-quiet>
+
+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 key>
+
+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.
+
+=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 or TLS as appropriate.
+
+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.
+
+=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<-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
+normal verbose output.
+
+=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.
+
+=item B<-starttls protocol>
+
+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", "xmpp", "xmpp-server",
+and "irc."
+
+=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<filename>
+
+=item B<-sess_in sess.pem>
+
+load SSL session from B<filename>. The client will attempt to resume a
+connection from this session.
+
+=item B<-engine id>
+
+specifying an engine (by its unique B<id> string) will cause B<s_client>
+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.
+
+=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)>).
+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
+
+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.
+
+=head1 NOTES
+
+B<s_client> can be used to debug SSL servers. To connect to an SSL HTTP
+server the command:
+
+ openssl s_client -connect servername:443
+
+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<-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.
+
+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 B<s_client> 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 B<-prexit> option and send an HTTP request
+for an appropriate page.
+
+If a certificate is specified on the command line using the B<-cert>
+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.
+
+If there are problems verifying a server certificate then the
+B<-showcerts> option can be used to show the whole chain.
+
+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
+
+Because this program has a lot of options and also because some of
+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<-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)>, L<s_server(1)>, L<ciphers(1)>
+
+=head1 HISTORY
+
+The -no_alt_chains options was first added to OpenSSL 1.1.0.
+
+=cut
=head1 SYNOPSIS
B<openssl> B<s_server>
+[B<-help>]
[B<-accept port>]
[B<-naccept count>]
[B<-context id>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-accept port>
the TCP port to listen on for connections. If not specified 4433 is used.
--- /dev/null
+
+=pod
+
+=head1 NAME
+
+s_server - SSL/TLS server program
+
+=head1 SYNOPSIS
+
+B<openssl> B<s_server>
+[B<-accept port>]
+[B<-naccept count>]
+[B<-context id>]
+[B<-verify depth>]
+[B<-Verify depth>]
+[B<-crl_check>]
+[B<-crl_check_all>]
+[B<-cert filename>]
+[B<-certform DER|PEM>]
+[B<-key keyfile>]
+[B<-keyform DER|PEM>]
+[B<-pass arg>]
+[B<-dcert filename>]
+[B<-dcertform DER|PEM>]
+[B<-dkey keyfile>]
+[B<-dkeyform DER|PEM>]
+[B<-dpass arg>]
+[B<-dhparam filename>]
+[B<-nbio>]
+[B<-nbio_test>]
+[B<-crlf>]
+[B<-debug>]
+[B<-msg>]
+[B<-state>]
+[B<-CApath directory>]
+[B<-CAfile filename>]
+[B<-no-CAfile>]
+[B<-no-CApath>]
+[B<-attime timestamp>]
+[B<-check_ss_sig>]
+[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_return_error>]
+[B<-verify_email email>]
+[B<-verify_hostname hostname>]
+[B<-verify_ip ip>]
+[B<-verify_name name>]
+[B<-x509_strict>]
+[B<-nocert>]
+[B<-cipher cipherlist>]
+[B<-serverpref>]
+[B<-quiet>]
+[B<-ssl3>]
+[B<-tls1>]
+[B<-dtls>]
+[B<-dtls1>]
+[B<-dtls1_2>]
+[B<-listen>]
+[B<-async>]
+[B<-no_ssl3>]
+[B<-no_tls1>]
+[B<-no_dhe>]
+[B<-bugs>]
+[B<-comp>]
+[B<-no_comp>]
+[B<-brief>]
+[B<-www>]
+[B<-WWW>]
+[B<-HTTP>]
+[B<-engine id>]
+[B<-tlsextdebug>]
+[B<-no_ticket>]
+[B<-id_prefix arg>]
+[B<-rand file(s)>]
+[B<-serverinfo file>]
+[B<-no_resumption_on_reneg>]
+[B<-status>]
+[B<-status_verbose>]
+[B<-status_timeout nsec>]
+[B<-status_url url>]
+[B<-nextprotoneg protocols>]
+
+=head1 DESCRIPTION
+
+The B<s_server> command implements a generic SSL/TLS server which listens
+for connections on a given port using SSL/TLS.
+
+=head1 OPTIONS
+
+In addition to the options below the B<s_server> utility also supports the
+common and server only options documented in the
+L<SSL_CONF_cmd(3)|SSL_CONF_cmd(3)/SUPPORTED COMMAND LINE COMMANDS> manual
+page.
+
+=over 4
+
+=item B<-accept port>
+
+the TCP port to listen on for connections. If not specified 4433 is used.
+
+=item B<-naccept count>
+
+The server will exit after receiving B<number> connections, default unlimited.
+
+=item B<-context id>
+
+sets the SSL context id. It can be given any string value. If this option
+is not present a default value will be used.
+
+=item B<-cert certname>
+
+The certificate to use, most servers cipher suites require the use of a
+certificate and some require a certificate with a certain public key type:
+for example the DSS cipher suites require a certificate containing a DSS
+(DSA) key. If not specified then the filename "server.pem" will be used.
+
+=item B<-certform format>
+
+The certificate format to use: DER or PEM. PEM is the default.
+
+=item B<-key keyfile>
+
+The private key to use. If not specified then the certificate file will
+be used.
+
+=item B<-keyform format>
+
+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>
+see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)>.
+
+=item B<-dcert filename>, B<-dkey keyname>
+
+specify an additional certificate and private key, these behave in the
+same manner as the B<-cert> and B<-key> options except there is no default
+if they are not specified (no additional certificate and key is used). As
+noted above some cipher suites require a certificate containing a key of
+a certain type. Some cipher suites need a certificate carrying an RSA key
+and some a DSS (DSA) key. By using RSA and DSS certificates and keys
+a server can support clients which only support RSA or DSS cipher suites
+by using an appropriate certificate.
+
+=item B<-dcertform format>, B<-dkeyform format>, B<-dpass arg>
+
+additional certificate and private key format and passphrase respectively.
+
+=item B<-nocert>
+
+if this option is set then no certificate is used. This restricts the
+cipher suites available to the anonymous ones (currently just anonymous
+DH).
+
+=item B<-dhparam filename>
+
+the DH parameter file to use. The ephemeral DH cipher suites generate keys
+using a set of DH parameters. If not specified then an attempt is made to
+load the parameters from the server certificate file. If this fails then
+a static set of parameters hard coded into the s_server program will be used.
+
+=item B<-no_dhe>
+
+if this option is set then no DH parameters will be loaded effectively
+disabling the ephemeral DH cipher suites.
+
+=item B<-crl_check>, B<-crl_check_all>
+
+Check the peer certificate has not been revoked by its CA.
+The CRL(s) are appended to the certificate file. With the B<-crl_check_all>
+option all CRLs of all CAs in the chain are checked.
+
+=item B<-CApath directory>
+
+The directory to use for client certificate verification. This directory
+must be in "hash format", see B<verify> for more information. These are
+also used when building the server certificate chain.
+
+=item B<-CAfile file>
+
+A file containing trusted certificates to use during client authentication
+and to use when attempting to build the server certificate chain. The list
+is also used in the list of acceptable client CAs passed to the client when
+a certificate is requested.
+
+=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<-verify depth>, B<-Verify depth>
+
+The verify depth to use. This specifies the maximum length of the
+client certificate chain and makes the server request a certificate from
+the client. With the B<-verify> option a certificate is requested but the
+client does not have to send one, with the B<-Verify> option the client
+must supply a certificate or an error occurs.
+
+If the ciphersuite cannot request a client certificate (for example an
+anonymous ciphersuite or PSK) this option has no effect.
+
+=item B<-attime>, B<-check_ss_sig>, 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 different peer certificate verification options.
+See the L<verify(1)> manual page for details.
+
+=item B<-verify_return_error>
+
+Verification errors normally just print a message but allow the
+connection to continue, for debugging purposes.
+If this option is used, then verification errors close the connection.
+
+=item B<-state>
+
+prints out the SSL session states.
+
+=item B<-debug>
+
+print extensive debugging information including a hex dump of all traffic.
+
+=item B<-msg>
+
+show all protocol messages with hex dump.
+
+=item B<-trace>
+
+show verbose trace output of protocol messages. OpenSSL needs to be compiled
+with B<enable-ssl-trace> 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
+
+=item B<-nbio>
+
+turns on non blocking I/O
+
+=item B<-crlf>
+
+this option translated a line feed from the terminal into CR+LF.
+
+=item B<-quiet>
+
+inhibit printing of session and certificate information.
+
+=item B<-psk_hint hint>
+
+Use the PSK identity hint B<hint> when using a PSK cipher suite.
+
+=item B<-psk key>
+
+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.
+
+=item B<-ssl3>, B<-tls1>, B<-no_ssl3>, B<-no_tls1>
+
+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 or TLS as appropriate.
+
+=item B<-dtls>, B<-dtls1>, B<-dtls1_2>
+
+these options make s_server use DTLS protocols instead of TLS. With B<-dtls>
+s_server will negotiate any supported DTLS protcol version, whilst B<-dtls1> and
+B<-dtls1_2> will only support DTLS1.0 and DTLS1.2 respectively.
+
+=item B<-listen>
+
+this option can only be used in conjunction with one of the DTLS options above.
+With this option s_server will listen on a UDP port for incoming connections.
+Any ClientHellos that arrive will be checked to see if they have a cookie in
+them or not. Any without a cookie will be responded to with a
+HelloVerifyRequest. If a ClientHello with a cookie is received then s_server
+will connect to that peer and complete the handshake.
+
+=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<-comp>
+
+Enable negotiation of 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>
+
+Disable negotiation of 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
+normal verbose output.
+
+=item B<-cipher cipherlist>
+
+this allows the cipher list used by the server to be modified. When
+the client sends a list of supported ciphers the first client cipher
+also included in the server list is used. Because the client specifies
+the preference order, the order of the server cipherlist irrelevant. See
+the B<ciphers> command for more information.
+
+=item B<-serverpref>
+
+use the server's cipher preferences, rather than the client's preferences.
+
+=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<-www>
+
+sends a status message back to the client when it connects. This includes
+lots of information about the ciphers used and various session parameters.
+The output is in HTML format so this option will normally be used with a
+web browser.
+
+=item B<-WWW>
+
+emulates a simple web server. Pages will be resolved relative to the
+current directory, for example if the URL https://myhost/page.html is
+requested the file ./page.html will be loaded.
+
+=item B<-HTTP>
+
+emulates a simple web server. Pages will be resolved relative to the
+current directory, for example if the URL https://myhost/page.html is
+requested the file ./page.html will be loaded. The files loaded are
+assumed to contain a complete and correct HTTP response (lines that
+are part of the HTTP response line and headers must end with CRLF).
+
+=item B<-rev>
+
+simple test server which just reverses the text received from the client
+and sends it back to the server. Also sets B<-brief>.
+
+=item B<-engine id>
+
+specifying an engine (by its unique B<id> string) will cause B<s_server>
+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.
+
+=item B<-id_prefix arg>
+
+generate SSL/TLS session IDs prefixed by B<arg>. This is mostly useful
+for testing any SSL/TLS code (eg. proxies) that wish to deal with multiple
+servers, when each of which might be generating a unique range of session
+IDs (eg. with a certain prefix).
+
+=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)>).
+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 file>
+
+a file containing one or more blocks of PEM data. Each PEM block
+must encode a TLS ServerHello extension (2 bytes type, 2 bytes length,
+followed by "length" bytes of extension data). If the client sends
+an empty TLS ClientHello extension matching the type, the corresponding
+ServerHello extension will be returned.
+
+=item B<-no_resumption_on_reneg>
+
+set SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION flag.
+
+=item B<-status>
+
+enables certificate status request support (aka OCSP stapling).
+
+=item B<-status_verbose>
+
+enables certificate status request support (aka OCSP stapling) and gives
+a verbose printout of the OCSP response.
+
+=item B<-status_timeout nsec>
+
+sets the timeout for OCSP response to B<nsec> seconds.
+
+=item B<-status_url url>
+
+sets a fallback responder URL to use if no responder URL is present in the
+server certificate. Without this option an error is returned if the server
+certificate does not contain a responder address.
+
+=item B<-nextprotoneg protocols>
+
+enable Next Protocol Negotiation TLS extension and provide a
+comma-separated list of supported protocol names.
+The list should contain most wanted protocols first.
+Protocol names are printable ASCII strings, for example "http/1.1" or
+"spdy/3".
+
+=back
+
+=head1 CONNECTED COMMANDS
+
+If a connection request is established with an SSL client and neither the
+B<-www> nor the B<-WWW> option has been used then normally any data received
+from the client is displayed and any key presses will be sent to the client.
+
+Certain single letter commands are also recognized which perform special
+operations: these are listed below.
+
+=over 4
+
+=item B<q>
+
+end the current SSL connection but still accept new connections.
+
+=item B<Q>
+
+end the current SSL connection and exit.
+
+=item B<r>
+
+renegotiate the SSL session.
+
+=item B<R>
+
+renegotiate the SSL session and request a client certificate.
+
+=item B<P>
+
+send some plain text down the underlying TCP connection: this should
+cause the client to disconnect due to a protocol violation.
+
+=item B<S>
+
+print out some session cache status information.
+
+=back
+
+=head1 NOTES
+
+B<s_server> can be used to debug SSL clients. To accept connections from
+a web browser the command:
+
+ openssl s_server -accept 443 -www
+
+can be used for example.
+
+Most web browsers (in particular Netscape and MSIE) only support RSA cipher
+suites, so they cannot connect to servers which don't use a certificate
+carrying an RSA key or a version of OpenSSL with RSA disabled.
+
+Although specifying an empty list of CAs when requesting a client certificate
+is strictly speaking a protocol violation, some SSL clients interpret this to
+mean any CA is acceptable. This is useful for debugging purposes.
+
+The session parameters can printed out using the B<sess_id> program.
+
+=head1 BUGS
+
+Because this program has a lot of options and also because some of
+the techniques used are rather old, the C source of s_server is rather
+hard to read and not a model of how things should be done. A typical
+SSL server program would be much simpler.
+
+The output of common ciphers is wrong: it just gives the list of ciphers that
+OpenSSL recognizes and the client supports.
+
+There should be a way for the B<s_server> program to print out details of any
+unknown cipher suites a client says it supports.
+
+=head1 SEE ALSO
+
+L<sess_id(1)>, L<s_client(1)>, L<ciphers(1)>
+
+=head1 HISTORY
+
+The -no_alt_chains options was first added to OpenSSL 1.1.0.
+
+=cut
=head1 SYNOPSIS
B<openssl> B<s_time>
+[B<-help>]
[B<-connect host:port>]
[B<-www page>]
[B<-cert filename>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-connect host:port>
This specifies the host and optional port to connect to.
=head1 SYNOPSIS
B<openssl> B<sess_id>
+[B<-help>]
[B<-inform PEM|DER>]
[B<-outform PEM|DER|NSS>]
[B<-in filename>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-inform DER|PEM>
This specifies the input format. The B<DER> option uses an ASN1 DER encoded
=head1 SYNOPSIS
B<openssl> B<smime>
+[B<-help>]
[B<-encrypt>]
[B<-decrypt>]
[B<-sign>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-encrypt>
encrypt mail for the given recipient certificates. Input file is the message
=head1 SYNOPSIS
B<openssl> B<spkac>
+[B<-help>]
[B<-in filename>]
[B<-out filename>]
[B<-key keyfile>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-in filename>
This specifies the input filename to read from or standard input if this
B<openssl> B<ts>
B<-query>
+[B<-help>]
[B<-rand> file:file...]
[B<-config> configfile]
[B<-data> file_to_hash]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-rand> file:file...
The files containing random data for seeding the random number
=head1 SYNOPSIS
B<openssl> B<verify>
+[B<-help>]
[B<-CAfile file>]
[B<-CApath directory>]
[B<-no-CAfile>]
[B<-engine id>]
[B<-explicit_policy>]
[B<-extended_crl>]
-[B<-help>]
[B<-ignore_critical>]
[B<-inhibit_any>]
[B<-inhibit_map>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-CAfile file>
A B<file> of trusted certificates.
Enable extended CRL features such as indirect CRLs and alternate CRL
signing keys.
-=item B<-help>
-
-Print out a usage message.
-
=item B<-ignore_critical>
Normally if an unhandled critical extension is present which is not
=head1 SYNOPSIS
B<openssl version>
+[B<-help>]
[B<-a>]
[B<-v>]
[B<-b>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-a>
all information, this is the same as setting all the other flags.
=head1 SYNOPSIS
B<openssl> B<x509>
+[B<-help>]
[B<-inform DER|PEM|NET>]
[B<-outform DER|PEM|NET>]
[B<-keyform DER|PEM>]
=over 4
+=item B<-help>
+
+Print out a usage message.
+
=item B<-inform DER|PEM|NET>
This specifies the input format normally the command will expect an X509
projects / oweals / openssl.git / commitdiff