2 {- OpenSSL::safe::output_do_not_edit_headers(); -}
6 openssl-s_client - SSL/TLS client program
10 B<openssl> B<s_client>
12 [B<-connect> I<host:port>]
13 [B<-bind> I<host:port>]
14 [B<-proxy> I<host:port>]
15 [B<-proxy_user> I<userid>]
16 [B<-proxy_pass> I<arg>]
20 [B<-servername> I<name>]
23 [B<-verify_return_error>]
24 [B<-cert> I<filename>]
25 [B<-certform> B<DER>|B<PEM>]
26 [B<-CRLform> B<DER>|B<PEM>]
28 [B<-keyform> B<DER>|B<PEM>]
29 [B<-cert_chain> I<filename>]
32 [B<-chainCApath> I<directory>]
33 [B<-chainCAfile> I<filename>]
34 [B<-chainCAstore> I<uri>]
35 [B<-requestCAfile> I<filename>]
36 [B<-dane_tlsa_domain> I<domain>]
37 [B<-dane_tlsa_rrdata> I<rrdata>]
38 [B<-dane_ee_no_namechecks>]
39 [B<-attime> I<timestamp>]
53 [B<-purpose> I<purpose>]
60 [B<-auth_level> I<num>]
61 [B<-verify_depth> I<num>]
62 [B<-verify_email> I<email>]
63 [B<-verify_hostname> I<hostname>]
65 [B<-verify_name> I<name>]
78 [B<-psk_identity> I<identity>]
80 [B<-psk_session> I<file>]
100 [B<-split_send_frag>]
106 [B<-allow_no_dhe_kex>]
107 [B<-sigalgs> I<sigalglist>]
108 [B<-curves> I<curvelist>]
109 [B<-cipher> I<cipherlist>]
110 [B<-ciphersuites> I<val>]
112 [B<-starttls> I<protocol>]
113 [B<-xmpphost> I<hostname>]
114 [B<-name> I<hostname>]
117 [B<-sess_out> I<filename>]
118 [B<-sess_in> I<filename>]
119 [B<-serverinfo> I<types>]
121 [B<-alpn> I<protocols>]
122 [B<-nextprotoneg> I<protocols>]
126 [B<-keylogfile> I<file>]
127 [B<-early_data> I<file>]
129 {- $OpenSSL::safe::opt_name_synopsis -}
130 {- $OpenSSL::safe::opt_x_synopsis -}
131 {- $OpenSSL::safe::opt_trust_synopsis -}
132 {- $OpenSSL::safe::opt_r_synopsis -}
133 {- $OpenSSL::safe::opt_engine_synopsis -}
136 =for openssl ifdef engine ssl_client_engine ct noct ctlogfile
138 =for openssl ifdef ssl3 unix 4 6 use_srtp status trace wdebug nextprotoneg
140 =for openssl ifdef ssl3 tls1 tls1_1 tls1_2 tls1_3 dtls mtu dtls1 dtls1_2
142 =for openssl ifdef sctp_label_bug sctp
144 =for openssl ifdef srpuser srppass srp_lateuser srp_moregroups srp_strength
148 This command implements a generic SSL/TLS client which
149 connects to a remote host using SSL/TLS. It is a I<very> useful diagnostic
150 tool for SSL servers.
154 In addition to the options below, this command also supports the
155 common and client only options documented
156 in the "Supported Command Line Commands" section of the L<SSL_CONF_cmd(3)>
163 Print out a usage message.
165 =item B<-connect> I<host>:I<port>
167 This specifies the host and optional port to connect to. It is possible to
168 select the host and port using the optional target positional argument instead.
169 If neither this nor the target positional argument are specified then an attempt
170 is made to connect to the local host on port 4433.
172 =item B<-bind> I<host:port>
174 This specifies the host address and or port to bind as the source for the
175 connection. For Unix-domain sockets the port is ignored and the host is
176 used as the source socket address.
178 =item B<-proxy> I<host:port>
180 When used with the B<-connect> flag, the program uses the host and port
181 specified with this flag and issues an HTTP CONNECT command to connect
182 to the desired server.
184 =item B<-proxy_user> I<userid>
186 When used with the B<-proxy> flag, the program will attempt to authenticate
187 with the specified proxy using basic (base64) authentication.
188 NB: Basic authentication is insecure; the credentials are sent to the proxy
189 in easily reversible base64 encoding before any TLS/SSL session is established.
190 Therefore these credentials are easily recovered by anyone able to sniff/trace
191 the network. Use with caution.
193 =item B<-proxy_pass> I<arg>
195 The proxy password source, used with the B<-proxy_user> flag.
196 For more information about the format of B<arg>
197 see L<openssl(1)/Pass Phrase Options>.
199 =item B<-unix> I<path>
201 Connect over the specified Unix-domain socket.
211 =item B<-servername> I<name>
213 Set the TLS SNI (Server Name Indication) extension in the ClientHello message to
215 If B<-servername> is not provided, the TLS SNI extension will be populated with
216 the name given to B<-connect> if it follows a DNS name format. If B<-connect> is
217 not provided either, the SNI is set to "localhost".
218 This is the default since OpenSSL 1.1.1.
220 Even though SNI should normally be a DNS name and not an IP address, if
221 B<-servername> is provided then that name will be sent, regardless of whether
222 it is a DNS name or not.
224 This option cannot be used in conjunction with B<-noservername>.
226 =item B<-noservername>
228 Suppresses sending of the SNI (Server Name Indication) extension in the
229 ClientHello message. Cannot be used in conjunction with the B<-servername> or
230 <-dane_tlsa_domain> options.
232 =item B<-cert> I<certname>
234 The certificate to use, if one is requested by the server. The default is
235 not to use a certificate.
237 =item B<-certform> I<format>
239 The certificate format to use: DER or PEM. PEM is the default.
241 =item B<-CRLform> B<DER>|B<PEM>
243 The CRL format; the default is B<PEM>.
244 See L<openssl(1)/Format Options> for details.
246 =item B<-key> I<keyfile>
248 The private key to use. If not specified then the certificate file will
251 =item B<-keyform> I<format>
253 The key format; the default is B<PEM>.
254 See L<openssl(1)/Format Options> for details.
258 A file containing trusted certificates to use when attempting to build the
259 client/server certificate chain related to the certificate specified via the
262 =item B<-build_chain>
264 Specify whether the application should build the certificate chain to be
265 provided to the server.
267 =item B<-pass> I<arg>
269 the private key password source. For more information about the format of I<arg>
270 see L<openssl(1)/Pass phrase options>.
272 =item B<-verify> I<depth>
274 The verify depth to use. This specifies the maximum length of the
275 server certificate chain and turns on server certificate verification.
276 Currently the verify operation continues after errors so all the problems
277 with a certificate chain can be seen. As a side effect the connection
278 will never fail due to a server certificate verify failure.
280 =item B<-verify_return_error>
282 Return verification errors instead of continuing. This will typically
283 abort the handshake with a fatal error.
285 =item B<-chainCApath> I<directory>
287 The directory to use for building the chain provided to the server. This
288 directory must be in "hash format", see L<openssl-verify(1)> for more
291 =item B<-chainCAfile> I<file>
293 A file containing trusted certificates to use when attempting to build the
294 client certificate chain.
296 =item B<-chainCAstore> I<uri>
298 The URI to use when attempting to build the client certificate chain.
300 =item B<-requestCAfile> I<file>
302 A file containing a list of certificates whose subject names will be sent
303 to the server in the B<certificate_authorities> extension. Only supported
306 =item B<-dane_tlsa_domain> I<domain>
308 Enable RFC6698/RFC7671 DANE TLSA authentication and specify the
309 TLSA base domain which becomes the default SNI hint and the primary
310 reference identifier for hostname checks. This must be used in
311 combination with at least one instance of the B<-dane_tlsa_rrdata>
314 When DANE authentication succeeds, the diagnostic output will include
315 the lowest (closest to 0) depth at which a TLSA record authenticated
316 a chain certificate. When that TLSA record is a "2 1 0" trust
317 anchor public key that signed (rather than matched) the top-most
318 certificate of the chain, the result is reported as "TA public key
319 verified". Otherwise, either the TLSA record "matched TA certificate"
320 at a positive depth or else "matched EE certificate" at depth 0.
322 =item B<-dane_tlsa_rrdata> I<rrdata>
324 Use one or more times to specify the RRDATA fields of the DANE TLSA
325 RRset associated with the target service. The I<rrdata> value is
326 specied in "presentation form", that is four whitespace separated
327 fields that specify the usage, selector, matching type and associated
328 data, with the last of these encoded in hexadecimal. Optional
329 whitespace is ignored in the associated data field. For example:
331 $ openssl s_client -brief -starttls smtp \
332 -connect smtp.example.com:25 \
333 -dane_tlsa_domain smtp.example.com \
334 -dane_tlsa_rrdata "2 1 1
335 B111DD8A1C2091A89BD4FD60C57F0716CCE50FEEFF8137CDBEE0326E 02CF362B" \
336 -dane_tlsa_rrdata "2 1 1
337 60B87575447DCBA2A36B7D11AC09FB24A9DB406FEE12D2CC90180517 616E8A18"
340 Verified peername: smtp.example.com
341 DANE TLSA 2 1 1 ...ee12d2cc90180517616e8a18 matched TA certificate at depth 1
344 =item B<-dane_ee_no_namechecks>
346 This disables server name checks when authenticating via DANE-EE(3) TLSA
348 For some applications, primarily web browsers, it is not safe to disable name
349 checks due to "unknown key share" attacks, in which a malicious server can
350 convince a client that a connection to a victim server is instead a secure
351 connection to the malicious server.
352 The malicious server may then be able to violate cross-origin scripting
354 Thus, despite the text of RFC7671, name checks are by default enabled for
355 DANE-EE(3) TLSA records, and can be disabled in applications where it is safe
357 In particular, SMTP and XMPP clients should set this option as SRV and MX
358 records already make it possible for a remote domain to redirect client
359 connections to any server of its choice, and in any case SMTP and XMPP clients
360 do not execute scripts downloaded from remote servers.
362 =item B<-attime>, B<-check_ss_sig>, B<-crl_check>, B<-crl_check_all>,
363 B<-explicit_policy>, B<-extended_crl>, B<-ignore_critical>, B<-inhibit_any>,
364 B<-inhibit_map>, B<-no_alt_chains>, B<-no_check_time>, B<-partial_chain>, B<-policy>,
365 B<-policy_check>, B<-policy_print>, B<-purpose>, B<-suiteB_128>,
366 B<-suiteB_128_only>, B<-suiteB_192>, B<-trusted_first>, B<-use_deltas>,
367 B<-auth_level>, B<-verify_depth>, B<-verify_email>, B<-verify_hostname>,
368 B<-verify_ip>, B<-verify_name>, B<-x509_strict>
370 Set various certificate chain validation options. See the
371 L<openssl-verify(1)> manual page for details.
375 Reconnects to the same server 5 times using the same session ID, this can
376 be used as a test that session caching is working.
380 Displays the server certificate list as sent by the server: it only consists of
381 certificates the server has sent (in the order the server has sent them). It is
382 B<not> a verified chain.
386 Print session information when the program exits. This will always attempt
387 to print out information even if the connection fails. Normally information
388 will only be printed out once if the connection succeeds. This option is useful
389 because the cipher in use may be renegotiated or the connection may fail
390 because a client certificate is required or is requested only after an
391 attempt is made to access a certain URL. Note: the output produced by this
392 option is not always accurate because a connection might never have been
397 Prints out the SSL session states.
401 Print extensive debugging information including a hex dump of all traffic.
405 Show all protocol messages with hex dump.
409 Show verbose trace output of protocol messages. OpenSSL needs to be compiled
410 with B<enable-ssl-trace> for this option to work.
414 File to send output of B<-msg> or B<-trace> to, default standard output.
418 Tests non-blocking I/O
422 Turns on non-blocking I/O
426 This option translated a line feed from the terminal into CR+LF as required
431 Inhibit shutting down the connection when end of file is reached in the
436 Inhibit printing of session and certificate information. This implicitly
437 turns on B<-ign_eof> as well.
441 Shut down the connection when end of file is reached in the input.
442 Can be used to override the implicit B<-ign_eof> after B<-quiet>.
444 =item B<-psk_identity> I<identity>
446 Use the PSK identity I<identity> when using a PSK cipher suite.
447 The default value is "Client_identity" (without the quotes).
451 Use the PSK key I<key> when using a PSK cipher suite. The key is
452 given as a hexadecimal number without leading 0x, for example -psk
454 This option must be provided in order to use a PSK cipher.
456 =item B<-psk_session> I<file>
458 Use the pem encoded SSL_SESSION data stored in I<file> as the basis of a PSK.
459 Note that this will only work if TLSv1.3 is negotiated.
461 =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>
463 These options require or disable the use of the specified SSL or TLS protocols.
464 By default, this command will negotiate the highest mutually supported protocol
466 When a specific TLS version is required, only that version will be offered to
467 and accepted from the server.
468 Note that not all protocols and flags may be available, depending on how
471 =item B<-dtls>, B<-dtls1>, B<-dtls1_2>
473 These options make this command use DTLS protocols instead of TLS.
474 With B<-dtls>, it will negotiate any supported DTLS protocol version,
475 whilst B<-dtls1> and B<-dtls1_2> will only support DTLS1.0 and DTLS1.2
480 Use SCTP for the transport protocol instead of UDP in DTLS. Must be used in
481 conjunction with B<-dtls>, B<-dtls1> or B<-dtls1_2>. This option is only
482 available where OpenSSL has support for SCTP enabled.
484 =item B<-sctp_label_bug>
486 Use the incorrect behaviour of older OpenSSL implementations when computing
487 endpoint-pair shared secrets for DTLS/SCTP. This allows communication with
488 older broken implementations but breaks interoperability with correct
489 implementations. Must be used in conjunction with B<-sctp>. This option is only
490 available where OpenSSL has support for SCTP enabled.
492 =item B<-fallback_scsv>
494 Send TLS_FALLBACK_SCSV in the ClientHello.
498 Switch on asynchronous mode. Cryptographic operations will be performed
499 asynchronously. This will only have an effect if an asynchronous capable engine
500 is also used via the B<-engine> option. For test purposes the dummy async engine
501 (dasync) can be used (if available).
503 =item B<-max_send_frag> I<int>
505 The maximum size of data fragment to send.
506 See L<SSL_CTX_set_max_send_fragment(3)> for further information.
508 =item B<-split_send_frag> I<int>
510 The size used to split data for encrypt pipelines. If more data is written in
511 one go than this value then it will be split into multiple pipelines, up to the
512 maximum number of pipelines defined by max_pipelines. This only has an effect if
513 a suitable cipher suite has been negotiated, an engine that supports pipelining
514 has been loaded, and max_pipelines is greater than 1. See
515 L<SSL_CTX_set_split_send_fragment(3)> for further information.
517 =item B<-max_pipelines> I<int>
519 The maximum number of encrypt/decrypt pipelines to be used. This will only have
520 an effect if an engine has been loaded that supports pipelining (e.g. the dasync
521 engine) and a suitable cipher suite has been negotiated. The default value is 1.
522 See L<SSL_CTX_set_max_pipelines(3)> for further information.
524 =item B<-read_buf> I<int>
526 The default read buffer size to be used for connections. This will only have an
527 effect if the buffer size is larger than the size that would otherwise be used
528 and pipelining is in use (see L<SSL_CTX_set_default_read_buffer_len(3)> for
529 further information).
533 There are several known bugs in SSL and TLS implementations. Adding this
534 option enables various workarounds.
538 Enables support for SSL/TLS compression.
539 This option was introduced in OpenSSL 1.1.0.
540 TLS compression is not recommended and is off by default as of
545 Disables support for SSL/TLS compression.
546 TLS compression is not recommended and is off by default as of
551 Only provide a brief summary of connection parameters instead of the
552 normal verbose output.
554 =item B<-sigalgs> I<sigalglist>
556 Specifies the list of signature algorithms that are sent by the client.
557 The server selects one entry in the list based on its preferences.
558 For example strings, see L<SSL_CTX_set1_sigalgs(3)>
560 =item B<-curves> I<curvelist>
562 Specifies the list of supported curves to be sent by the client. The curve is
563 ultimately selected by the server. For a list of all curves, use:
565 $ openssl ecparam -list_curves
567 =item B<-cipher> I<cipherlist>
569 This allows the TLSv1.2 and below cipher list sent by the client to be modified.
570 This list will be combined with any TLSv1.3 ciphersuites that have been
571 configured. Although the server determines which ciphersuite is used it should
572 take the first supported cipher in the list sent by the client. See
573 L<openssl-ciphers(1)> for more information.
575 =item B<-ciphersuites> I<val>
577 This allows the TLSv1.3 ciphersuites sent by the client to be modified. This
578 list will be combined with any TLSv1.2 and below ciphersuites that have been
579 configured. Although the server determines which cipher suite is used it should
580 take the first supported cipher in the list sent by the client. See
581 L<openssl-ciphers(1)> for more information. The format for this list is a simple
582 colon (":") separated list of TLSv1.3 ciphersuite names.
584 =item B<-starttls> I<protocol>
586 Send the protocol-specific message(s) to switch to TLS for communication.
587 I<protocol> is a keyword for the intended protocol. Currently, the only
588 supported keywords are "smtp", "pop3", "imap", "ftp", "xmpp", "xmpp-server",
589 "irc", "postgres", "mysql", "lmtp", "nntp", "sieve" and "ldap".
591 =item B<-xmpphost> I<hostname>
593 This option, when used with "-starttls xmpp" or "-starttls xmpp-server",
594 specifies the host for the "to" attribute of the stream element.
595 If this option is not specified, then the host specified with "-connect"
598 This option is an alias of the B<-name> option for "xmpp" and "xmpp-server".
600 =item B<-name> I<hostname>
602 This option is used to specify hostname information for various protocols
603 used with B<-starttls> option. Currently only "xmpp", "xmpp-server",
604 "smtp" and "lmtp" can utilize this B<-name> option.
606 If this option is used with "-starttls xmpp" or "-starttls xmpp-server",
607 if specifies the host for the "to" attribute of the stream element. If this
608 option is not specified, then the host specified with "-connect" will be used.
610 If this option is used with "-starttls lmtp" or "-starttls smtp", it specifies
611 the name to use in the "LMTP LHLO" or "SMTP EHLO" message, respectively. If
612 this option is not specified, then "mail.example.com" will be used.
614 =item B<-tlsextdebug>
616 Print out a hex dump of any TLS extensions received from the server.
620 Disable RFC4507bis session ticket support.
622 =item B<-sess_out> I<filename>
624 Output SSL session to I<filename>.
626 =item B<-sess_in> I<filename>
628 Load SSL session from I<filename>. The client will attempt to resume a
629 connection from this session.
631 =item B<-serverinfo> I<types>
633 A list of comma-separated TLS Extension Types (numbers between 0 and
634 65535). Each type will be sent as an empty ClientHello TLS Extension.
635 The server's response (if any) will be encoded and displayed as a PEM
640 Sends a certificate status request to the server (OCSP stapling). The server
641 response (if any) is printed out.
643 =item B<-alpn> I<protocols>, B<-nextprotoneg> I<protocols>
645 These flags enable the Enable the Application-Layer Protocol Negotiation
646 or Next Protocol Negotiation (NPN) extension, respectively. ALPN is the
647 IETF standard and replaces NPN.
648 The I<protocols> list is a comma-separated list of protocol names that
649 the client should advertise support for. The list should contain the most
650 desirable protocols first. Protocol names are printable ASCII strings,
651 for example "http/1.1" or "spdy/3".
652 An empty list of protocols is treated specially and will cause the
653 client to advertise support for the TLS extension but disconnect just
654 after receiving ServerHello with a list of server supported protocols.
655 The flag B<-nextprotoneg> cannot be specified if B<-tls1_3> is used.
657 =item B<-ct>, B<-noct>
659 Use one of these two options to control whether Certificate Transparency (CT)
660 is enabled (B<-ct>) or disabled (B<-noct>).
661 If CT is enabled, signed certificate timestamps (SCTs) will be requested from
662 the server and reported at handshake completion.
664 Enabling CT also enables OCSP stapling, as this is one possible delivery method
669 A file containing a list of known Certificate Transparency logs. See
670 L<SSL_CTX_set_ctlog_list_file(3)> for the expected file format.
672 =item B<-keylogfile> I<file>
674 Appends TLS secrets to the specified keylog file such that external programs
675 (like Wireshark) can decrypt TLS connections.
677 =item B<-early_data> I<file>
679 Reads the contents of the specified file and attempts to send it as early data
680 to the server. This will only work with resumed sessions that support early
681 data and when the server accepts the early data.
685 For TLSv1.3 only, send the Post-Handshake Authentication extension. This will
686 happen whether or not a certificate has been provided via B<-cert>.
688 =item I<host>:I<port>
690 Rather than providing B<-connect>, the target hostname and optional port may
691 be provided as a single positional argument after all options. If neither this
692 nor B<-connect> are provided, falls back to attempting to connect to
693 I<localhost> on port I<4433>.
695 {- $OpenSSL::safe::opt_name_item -}
697 {- $OpenSSL::safe::opt_x_item -}
699 {- $OpenSSL::safe::opt_trust_item -}
701 {- $OpenSSL::safe::opt_r_item -}
703 {- $OpenSSL::safe::opt_engine_item -}
707 =head1 CONNECTED COMMANDS
709 If a connection is established with an SSL server then any data received
710 from the server is displayed and any key presses will be sent to the
711 server. If end of file is reached then the connection will be closed down. When
712 used interactively (which means neither B<-quiet> nor B<-ign_eof> have been
713 given), then certain commands are also recognized which perform special
714 operations. These commands are a letter which must appear at the start of a
715 line. They are listed below.
721 End the current SSL connection and exit.
725 Renegotiate the SSL session (TLSv1.2 and below only).
729 Send a key update message to the server (TLSv1.3 only)
733 Send a key update message to the server and request one back (TLSv1.3 only)
739 This command can be used to debug SSL servers. To connect to an SSL HTTP
742 openssl s_client -connect servername:443
744 would typically be used (https uses port 443). If the connection succeeds
745 then an HTTP command can be given such as "GET /" to retrieve a web page.
747 If the handshake fails then there are several possible causes, if it is
748 nothing obvious like no client certificate then the B<-bugs>,
749 B<-ssl3>, B<-tls1>, B<-no_ssl3>, B<-no_tls1> options can be tried
750 in case it is a buggy server. In particular you should play with these
751 options B<before> submitting a bug report to an OpenSSL mailing list.
753 A frequent problem when attempting to get client certificates working
754 is that a web client complains it has no certificates or gives an empty
755 list to choose from. This is normally because the server is not sending
756 the clients certificate authority in its "acceptable CA list" when it
757 requests a certificate. By using this command, the CA list can be viewed
758 and checked. However some servers only request client authentication
759 after a specific URL is requested. To obtain the list in this case it
760 is necessary to use the B<-prexit> option and send an HTTP request
761 for an appropriate page.
763 If a certificate is specified on the command line using the B<-cert>
764 option it will not be used unless the server specifically requests
765 a client certificate. Therefor merely including a client certificate
766 on the command line is no guarantee that the certificate works.
768 If there are problems verifying a server certificate then the
769 B<-showcerts> option can be used to show all the certificates sent by the
772 This command is a test tool and is designed to continue the
773 handshake after any certificate verification errors. As a result it will
774 accept any certificate chain (trusted or not) sent by the peer. None test
775 applications should B<not> do this as it makes them vulnerable to a MITM
776 attack. This behaviour can be changed by with the B<-verify_return_error>
777 option: any verify errors are then returned aborting the handshake.
779 The B<-bind> option may be useful if the server or a firewall requires
780 connections to come from some particular address and or port.
784 Because this program has a lot of options and also because some of the
785 techniques used are rather old, the C source for this command is rather
786 hard to read and not a model of how things should be done.
787 A typical SSL client program would be much simpler.
789 The B<-prexit> option is a bit of a hack. We should really report
790 information whenever a session is renegotiated.
795 L<openssl-sess_id(1)>,
796 L<openssl-s_server(1)>,
797 L<openssl-ciphers(1)>,
799 L<SSL_CTX_set_max_send_fragment(3)>,
800 L<SSL_CTX_set_split_send_fragment(3)>,
801 L<SSL_CTX_set_max_pipelines(3)>,
802 L<ossl_store-file(7)>
806 The B<-no_alt_chains> option was added in OpenSSL 1.1.0.
807 The B<-name> option was added in OpenSSL 1.1.1.
811 Copyright 2000-2019 The OpenSSL Project Authors. All Rights Reserved.
813 Licensed under the Apache License 2.0 (the "License"). You may not use
814 this file except in compliance with the License. You can obtain a copy
815 in the file LICENSE in the source distribution or at
816 L<https://www.openssl.org/source/license.html>.