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Commit | Line | Data |
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a2151c5b DSH |
1 | =pod |
2 | ||
3 | =head1 NAME | |
4 | ||
5 | s_server - SSL/TLS server program | |
6 | ||
7 | =head1 SYNOPSIS | |
8 | ||
a2bbe594 | 9 | B<openssl> B<s_server> |
169394d4 | 10 | [B<-help>] |
a22f9c84 E |
11 | [B<-port port>] |
12 | [B<-accept val>] | |
642aa226 | 13 | [B<-naccept count>] |
a22f9c84 E |
14 | [B<-unix val>] |
15 | [B<-unlink>] | |
16 | [B<-4>] | |
17 | [B<-6>] | |
a2151c5b DSH |
18 | [B<-context id>] |
19 | [B<-verify depth>] | |
20 | [B<-Verify depth>] | |
51e00db2 LJ |
21 | [B<-crl_check>] |
22 | [B<-crl_check_all>] | |
a2151c5b | 23 | [B<-cert filename>] |
826a42a0 | 24 | [B<-certform DER|PEM>] |
a2151c5b | 25 | [B<-key keyfile>] |
826a42a0 DSH |
26 | [B<-keyform DER|PEM>] |
27 | [B<-pass arg>] | |
a2151c5b | 28 | [B<-dcert filename>] |
826a42a0 | 29 | [B<-dcertform DER|PEM>] |
a2151c5b | 30 | [B<-dkey keyfile>] |
826a42a0 DSH |
31 | [B<-dkeyform DER|PEM>] |
32 | [B<-dpass arg>] | |
a2151c5b DSH |
33 | [B<-dhparam filename>] |
34 | [B<-nbio>] | |
35 | [B<-nbio_test>] | |
36 | [B<-crlf>] | |
37 | [B<-debug>] | |
1d8634b1 | 38 | [B<-msg>] |
a2151c5b DSH |
39 | [B<-state>] |
40 | [B<-CApath directory>] | |
41 | [B<-CAfile filename>] | |
40e2d76b MC |
42 | [B<-no-CAfile>] |
43 | [B<-no-CApath>] | |
e42d84be HK |
44 | [B<-attime timestamp>] |
45 | [B<-check_ss_sig>] | |
46 | [B<-explicit_policy>] | |
47 | [B<-extended_crl>] | |
48 | [B<-ignore_critical>] | |
49 | [B<-inhibit_any>] | |
50 | [B<-inhibit_map>] | |
5a1f853b | 51 | [B<-no_check_time>] |
e42d84be HK |
52 | [B<-partial_chain>] |
53 | [B<-policy arg>] | |
54 | [B<-policy_check>] | |
55 | [B<-policy_print>] | |
56 | [B<-purpose purpose>] | |
57 | [B<-suiteB_128>] | |
58 | [B<-suiteB_128_only>] | |
59 | [B<-suiteB_192>] | |
6d3d5793 | 60 | [B<-trusted_first>] |
fa7b0111 | 61 | [B<-no_alt_chains>] |
e42d84be | 62 | [B<-use_deltas>] |
fbb82a60 | 63 | [B<-auth_level num>] |
a7c04f2b | 64 | [B<-nameopt option>] |
e42d84be | 65 | [B<-verify_depth num>] |
8d419330 | 66 | [B<-verify_return_error>] |
e42d84be HK |
67 | [B<-verify_email email>] |
68 | [B<-verify_hostname hostname>] | |
69 | [B<-verify_ip ip>] | |
70 | [B<-verify_name name>] | |
71 | [B<-x509_strict>] | |
a2151c5b DSH |
72 | [B<-nocert>] |
73 | [B<-cipher cipherlist>] | |
fc1d88f0 | 74 | [B<-serverpref>] |
a2151c5b | 75 | [B<-quiet>] |
a2151c5b DSH |
76 | [B<-ssl3>] |
77 | [B<-tls1>] | |
582a17d6 MC |
78 | [B<-tls1_1>] |
79 | [B<-tls1_2>] | |
80 | [B<-tls1_3>] | |
35d15a39 MC |
81 | [B<-dtls>] |
82 | [B<-dtls1>] | |
83 | [B<-dtls1_2>] | |
84 | [B<-listen>] | |
bc8857bf | 85 | [B<-async>] |
0df80881 MC |
86 | [B<-split_send_frag>] |
87 | [B<-max_pipelines>] | |
88 | [B<-read_buf>] | |
a2151c5b DSH |
89 | [B<-no_ssl3>] |
90 | [B<-no_tls1>] | |
8c73aeb6 VD |
91 | [B<-no_tls1_1>] |
92 | [B<-no_tls1_2>] | |
582a17d6 | 93 | [B<-no_tls1_3>] |
a2151c5b DSH |
94 | [B<-no_dhe>] |
95 | [B<-bugs>] | |
cc5a9ba4 VD |
96 | [B<-comp>] |
97 | [B<-no_comp>] | |
765b4137 | 98 | [B<-brief>] |
a2151c5b DSH |
99 | [B<-www>] |
100 | [B<-WWW>] | |
7b825005 | 101 | [B<-HTTP>] |
5270e702 | 102 | [B<-engine id>] |
d24a9c8f DSH |
103 | [B<-tlsextdebug>] |
104 | [B<-no_ticket>] | |
e986704d | 105 | [B<-id_prefix arg>] |
52b621db | 106 | [B<-rand file(s)>] |
9cd50f73 | 107 | [B<-serverinfo file>] |
36086186 | 108 | [B<-no_resumption_on_reneg>] |
cba3f1c7 DSH |
109 | [B<-status>] |
110 | [B<-status_verbose>] | |
111 | [B<-status_timeout nsec>] | |
112 | [B<-status_url url>] | |
acf65ae5 | 113 | [B<-status_file file>] |
776e15f9 | 114 | [B<-alpn protocols>] |
7efd0e77 | 115 | [B<-nextprotoneg protocols>] |
6437b802 MC |
116 | [B<-max_early_data>] |
117 | [B<-early_data>] | |
7efd0e77 | 118 | |
a2151c5b DSH |
119 | =head1 DESCRIPTION |
120 | ||
121 | The B<s_server> command implements a generic SSL/TLS server which listens | |
122 | for connections on a given port using SSL/TLS. | |
123 | ||
124 | =head1 OPTIONS | |
125 | ||
765b4137 DSH |
126 | In addition to the options below the B<s_server> utility also supports the |
127 | common and server only options documented in the | |
6f0ac0e2 RS |
128 | in the "Supported Command Line Commands" section of the L<SSL_CONF_cmd(3)> |
129 | manual page. | |
765b4137 | 130 | |
a2151c5b DSH |
131 | =over 4 |
132 | ||
169394d4 MR |
133 | =item B<-help> |
134 | ||
135 | Print out a usage message. | |
136 | ||
a22f9c84 | 137 | =item B<-port port> |
a2151c5b | 138 | |
8c73aeb6 | 139 | The TCP port to listen on for connections. If not specified 4433 is used. |
a2151c5b | 140 | |
a22f9c84 E |
141 | =item B<-accept val> |
142 | ||
143 | The optional TCP host and port to listen on for connections. If not specified, *:4433 is used. | |
144 | ||
642aa226 DSH |
145 | =item B<-naccept count> |
146 | ||
8c73aeb6 | 147 | The server will exit after receiving B<number> connections, default unlimited. |
642aa226 | 148 | |
a22f9c84 E |
149 | =item B<-unix val> |
150 | ||
151 | Unix domain socket to accept on. | |
152 | ||
153 | =item B<-unlink> | |
154 | ||
155 | For -unix, unlink existing socket first. | |
156 | ||
157 | =item B<-4> | |
158 | ||
159 | Use IPv4 only. | |
160 | ||
161 | =item B<-6> | |
162 | ||
163 | Use IPv6 only. | |
164 | ||
a2151c5b DSH |
165 | =item B<-context id> |
166 | ||
8c73aeb6 | 167 | Sets the SSL context id. It can be given any string value. If this option |
cc8709a0 | 168 | is not present a default value will be used. |
a2151c5b DSH |
169 | |
170 | =item B<-cert certname> | |
171 | ||
172 | The certificate to use, most servers cipher suites require the use of a | |
173 | certificate and some require a certificate with a certain public key type: | |
174 | for example the DSS cipher suites require a certificate containing a DSS | |
175 | (DSA) key. If not specified then the filename "server.pem" will be used. | |
176 | ||
826a42a0 DSH |
177 | =item B<-certform format> |
178 | ||
179 | The certificate format to use: DER or PEM. PEM is the default. | |
180 | ||
a2151c5b DSH |
181 | =item B<-key keyfile> |
182 | ||
183 | The private key to use. If not specified then the certificate file will | |
184 | be used. | |
185 | ||
826a42a0 DSH |
186 | =item B<-keyform format> |
187 | ||
188 | The private format to use: DER or PEM. PEM is the default. | |
189 | ||
190 | =item B<-pass arg> | |
191 | ||
8c73aeb6 | 192 | The private key password source. For more information about the format of B<arg> |
9b86974e | 193 | see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)>. |
826a42a0 | 194 | |
a2151c5b DSH |
195 | =item B<-dcert filename>, B<-dkey keyname> |
196 | ||
8c73aeb6 | 197 | Specify an additional certificate and private key, these behave in the |
a2151c5b DSH |
198 | same manner as the B<-cert> and B<-key> options except there is no default |
199 | if they are not specified (no additional certificate and key is used). As | |
200 | noted above some cipher suites require a certificate containing a key of | |
201 | a certain type. Some cipher suites need a certificate carrying an RSA key | |
202 | and some a DSS (DSA) key. By using RSA and DSS certificates and keys | |
203 | a server can support clients which only support RSA or DSS cipher suites | |
204 | by using an appropriate certificate. | |
205 | ||
826a42a0 DSH |
206 | =item B<-dcertform format>, B<-dkeyform format>, B<-dpass arg> |
207 | ||
8c73aeb6 | 208 | Additional certificate and private key format and passphrase respectively. |
826a42a0 | 209 | |
a2151c5b DSH |
210 | =item B<-nocert> |
211 | ||
8c73aeb6 | 212 | If this option is set then no certificate is used. This restricts the |
a2151c5b DSH |
213 | cipher suites available to the anonymous ones (currently just anonymous |
214 | DH). | |
215 | ||
216 | =item B<-dhparam filename> | |
217 | ||
8c73aeb6 | 218 | The DH parameter file to use. The ephemeral DH cipher suites generate keys |
a2151c5b | 219 | using a set of DH parameters. If not specified then an attempt is made to |
8c73aeb6 VD |
220 | load the parameters from the server certificate file. |
221 | If this fails then a static set of parameters hard coded into the B<s_server> | |
222 | program will be used. | |
a2151c5b | 223 | |
45ecfb19 | 224 | =item B<-no_dhe> |
a2151c5b | 225 | |
8c73aeb6 | 226 | If this option is set then no DH parameters will be loaded effectively |
a2151c5b DSH |
227 | disabling the ephemeral DH cipher suites. |
228 | ||
51e00db2 LJ |
229 | =item B<-crl_check>, B<-crl_check_all> |
230 | ||
231 | Check the peer certificate has not been revoked by its CA. | |
232 | The CRL(s) are appended to the certificate file. With the B<-crl_check_all> | |
233 | option all CRLs of all CAs in the chain are checked. | |
234 | ||
a2151c5b DSH |
235 | =item B<-CApath directory> |
236 | ||
237 | The directory to use for client certificate verification. This directory | |
238 | must be in "hash format", see B<verify> for more information. These are | |
239 | also used when building the server certificate chain. | |
240 | ||
241 | =item B<-CAfile file> | |
242 | ||
243 | A file containing trusted certificates to use during client authentication | |
244 | and to use when attempting to build the server certificate chain. The list | |
245 | is also used in the list of acceptable client CAs passed to the client when | |
246 | a certificate is requested. | |
247 | ||
40e2d76b MC |
248 | =item B<-no-CAfile> |
249 | ||
250 | Do not load the trusted CA certificates from the default file location | |
251 | ||
252 | =item B<-no-CApath> | |
253 | ||
254 | Do not load the trusted CA certificates from the default directory location | |
255 | ||
8d419330 RS |
256 | =item B<-verify depth>, B<-Verify depth> |
257 | ||
258 | The verify depth to use. This specifies the maximum length of the | |
259 | client certificate chain and makes the server request a certificate from | |
260 | the client. With the B<-verify> option a certificate is requested but the | |
261 | client does not have to send one, with the B<-Verify> option the client | |
262 | must supply a certificate or an error occurs. | |
263 | ||
264 | If the ciphersuite cannot request a client certificate (for example an | |
265 | anonymous ciphersuite or PSK) this option has no effect. | |
266 | ||
a7c04f2b DB |
267 | =item B<-nameopt option> |
268 | ||
269 | option which determines how the subject or issuer names are displayed. The | |
270 | B<option> argument can be a single option or multiple options separated by | |
271 | commas. Alternatively the B<-nameopt> switch may be used more than once to | |
272 | set multiple options. See the L<x509(1)> manual page for details. | |
273 | ||
d33def66 VD |
274 | =item B<-attime>, B<-check_ss_sig>, B<-crl_check>, B<-crl_check_all>, |
275 | B<-explicit_policy>, B<-extended_crl>, B<-ignore_critical>, B<-inhibit_any>, | |
5a1f853b | 276 | B<-inhibit_map>, B<-no_alt_chains>, B<-no_check_time>, B<-partial_chain>, B<-policy>, |
d33def66 VD |
277 | B<-policy_check>, B<-policy_print>, B<-purpose>, B<-suiteB_128>, |
278 | B<-suiteB_128_only>, B<-suiteB_192>, B<-trusted_first>, B<-use_deltas>, | |
fbb82a60 VD |
279 | B<-auth_level>, B<-verify_depth>, B<-verify_email>, B<-verify_hostname>, |
280 | B<-verify_ip>, B<-verify_name>, B<-x509_strict> | |
6d3d5793 | 281 | |
e42d84be | 282 | Set different peer certificate verification options. |
9b86974e | 283 | See the L<verify(1)> manual page for details. |
6d3d5793 | 284 | |
8d419330 RS |
285 | =item B<-verify_return_error> |
286 | ||
287 | Verification errors normally just print a message but allow the | |
288 | connection to continue, for debugging purposes. | |
289 | If this option is used, then verification errors close the connection. | |
290 | ||
a2151c5b DSH |
291 | =item B<-state> |
292 | ||
8c73aeb6 | 293 | Prints the SSL session states. |
a2151c5b DSH |
294 | |
295 | =item B<-debug> | |
296 | ||
8c73aeb6 | 297 | Print extensive debugging information including a hex dump of all traffic. |
a2151c5b | 298 | |
1d8634b1 BM |
299 | =item B<-msg> |
300 | ||
8c73aeb6 | 301 | Show all protocol messages with hex dump. |
1d8634b1 | 302 | |
8dbeb110 DSH |
303 | =item B<-trace> |
304 | ||
8c73aeb6 | 305 | Show verbose trace output of protocol messages. OpenSSL needs to be compiled |
8dbeb110 DSH |
306 | with B<enable-ssl-trace> for this option to work. |
307 | ||
308 | =item B<-msgfile> | |
309 | ||
8c73aeb6 | 310 | File to send output of B<-msg> or B<-trace> to, default standard output. |
8dbeb110 | 311 | |
a2151c5b DSH |
312 | =item B<-nbio_test> |
313 | ||
8c73aeb6 | 314 | Tests non blocking I/O |
a2151c5b DSH |
315 | |
316 | =item B<-nbio> | |
317 | ||
8c73aeb6 | 318 | Turns on non blocking I/O |
a2151c5b DSH |
319 | |
320 | =item B<-crlf> | |
321 | ||
8c73aeb6 | 322 | This option translated a line feed from the terminal into CR+LF. |
a2151c5b DSH |
323 | |
324 | =item B<-quiet> | |
325 | ||
8c73aeb6 | 326 | Inhibit printing of session and certificate information. |
a2151c5b | 327 | |
ddac1974 NL |
328 | =item B<-psk_hint hint> |
329 | ||
330 | Use the PSK identity hint B<hint> when using a PSK cipher suite. | |
331 | ||
332 | =item B<-psk key> | |
333 | ||
334 | Use the PSK key B<key> when using a PSK cipher suite. The key is | |
335 | given as a hexadecimal number without leading 0x, for example -psk | |
336 | 1a2b3c4d. | |
337 | ||
582a17d6 | 338 | =item B<-ssl2>, B<-ssl3>, B<-tls1>, B<-tls1_1>, B<-tls1_2>, B<-tls1_3>, B<-no_ssl2>, B<-no_ssl3>, B<-no_tls1>, B<-no_tls1_1>, B<-no_tls1_2>, B<-no_tls1_3> |
a2151c5b | 339 | |
8c73aeb6 VD |
340 | These options require or disable the use of the specified SSL or TLS protocols. |
341 | By default B<s_server> will negotiate the highest mutually supported protocol | |
342 | version. | |
343 | When a specific TLS version is required, only that version will be accepted | |
344 | from the client. | |
a2151c5b | 345 | |
35d15a39 MC |
346 | =item B<-dtls>, B<-dtls1>, B<-dtls1_2> |
347 | ||
8c73aeb6 | 348 | These options make B<s_server> use DTLS protocols instead of TLS. |
77a795e4 | 349 | With B<-dtls>, B<s_server> will negotiate any supported DTLS protocol version, |
8c73aeb6 VD |
350 | whilst B<-dtls1> and B<-dtls1_2> will only support DTLSv1.0 and DTLSv1.2 |
351 | respectively. | |
35d15a39 MC |
352 | |
353 | =item B<-listen> | |
354 | ||
8c73aeb6 VD |
355 | This option can only be used in conjunction with one of the DTLS options above. |
356 | With this option B<s_server> will listen on a UDP port for incoming connections. | |
35d15a39 | 357 | Any ClientHellos that arrive will be checked to see if they have a cookie in |
8c73aeb6 VD |
358 | them or not. |
359 | Any without a cookie will be responded to with a HelloVerifyRequest. | |
360 | If a ClientHello with a cookie is received then B<s_server> will connect to | |
361 | that peer and complete the handshake. | |
35d15a39 | 362 | |
bc8857bf MC |
363 | =item B<-async> |
364 | ||
8c73aeb6 | 365 | Switch on asynchronous mode. Cryptographic operations will be performed |
bc8857bf MC |
366 | asynchronously. This will only have an effect if an asynchronous capable engine |
367 | is also used via the B<-engine> option. For test purposes the dummy async engine | |
368 | (dasync) can be used (if available). | |
369 | ||
0df80881 MC |
370 | =item B<-split_send_frag int> |
371 | ||
372 | The size used to split data for encrypt pipelines. If more data is written in | |
373 | one go than this value then it will be split into multiple pipelines, up to the | |
374 | maximum number of pipelines defined by max_pipelines. This only has an effect if | |
375 | a suitable ciphersuite has been negotiated, an engine that supports pipelining | |
376 | has been loaded, and max_pipelines is greater than 1. See | |
377 | L<SSL_CTX_set_split_send_fragment(3)> for further information. | |
378 | ||
379 | =item B<-max_pipelines int> | |
380 | ||
381 | The maximum number of encrypt/decrypt pipelines to be used. This will only have | |
382 | an effect if an engine has been loaded that supports pipelining (e.g. the dasync | |
77a795e4 | 383 | engine) and a suitable ciphersuite has been negotiated. The default value is 1. |
0df80881 MC |
384 | See L<SSL_CTX_set_max_pipelines(3)> for further information. |
385 | ||
386 | =item B<-read_buf int> | |
387 | ||
388 | The default read buffer size to be used for connections. This will only have an | |
389 | effect if the buffer size is larger than the size that would otherwise be used | |
390 | and pipelining is in use (see L<SSL_CTX_set_default_read_buffer_len(3)> for | |
391 | further information). | |
392 | ||
a2151c5b DSH |
393 | =item B<-bugs> |
394 | ||
8c73aeb6 | 395 | There are several known bug in SSL and TLS implementations. Adding this |
a2151c5b DSH |
396 | option enables various workarounds. |
397 | ||
cc5a9ba4 VD |
398 | =item B<-comp> |
399 | ||
400 | Enable negotiation of TLS compression. | |
401 | This option was introduced in OpenSSL 1.1.0. | |
402 | TLS compression is not recommended and is off by default as of | |
403 | OpenSSL 1.1.0. | |
404 | ||
405 | =item B<-no_comp> | |
406 | ||
407 | Disable negotiation of TLS compression. | |
408 | TLS compression is not recommended and is off by default as of | |
409 | OpenSSL 1.1.0. | |
410 | ||
765b4137 DSH |
411 | =item B<-brief> |
412 | ||
8c73aeb6 VD |
413 | Provide a brief summary of connection parameters instead of the normal verbose |
414 | output. | |
765b4137 | 415 | |
a2151c5b DSH |
416 | =item B<-cipher cipherlist> |
417 | ||
8c73aeb6 | 418 | This allows the cipher list used by the server to be modified. When |
fabce041 DSH |
419 | the client sends a list of supported ciphers the first client cipher |
420 | also included in the server list is used. Because the client specifies | |
421 | the preference order, the order of the server cipherlist irrelevant. See | |
422 | the B<ciphers> command for more information. | |
a2151c5b | 423 | |
fc1d88f0 RS |
424 | =item B<-serverpref> |
425 | ||
8c73aeb6 | 426 | Use the server's cipher preferences, rather than the client's preferences. |
fc1d88f0 | 427 | |
d24a9c8f DSH |
428 | =item B<-tlsextdebug> |
429 | ||
8c73aeb6 | 430 | Print a hex dump of any TLS extensions received from the server. |
d24a9c8f DSH |
431 | |
432 | =item B<-no_ticket> | |
433 | ||
8c73aeb6 | 434 | Disable RFC4507bis session ticket support. |
d24a9c8f | 435 | |
a2151c5b DSH |
436 | =item B<-www> |
437 | ||
8c73aeb6 VD |
438 | Sends a status message back to the client when it connects. This includes |
439 | information about the ciphers used and various session parameters. | |
a2151c5b DSH |
440 | The output is in HTML format so this option will normally be used with a |
441 | web browser. | |
442 | ||
443 | =item B<-WWW> | |
444 | ||
8c73aeb6 | 445 | Emulates a simple web server. Pages will be resolved relative to the |
a2151c5b DSH |
446 | current directory, for example if the URL https://myhost/page.html is |
447 | requested the file ./page.html will be loaded. | |
448 | ||
7b825005 RL |
449 | =item B<-HTTP> |
450 | ||
8c73aeb6 | 451 | Emulates a simple web server. Pages will be resolved relative to the |
7b825005 RL |
452 | current directory, for example if the URL https://myhost/page.html is |
453 | requested the file ./page.html will be loaded. The files loaded are | |
454 | assumed to contain a complete and correct HTTP response (lines that | |
3b80e3aa | 455 | are part of the HTTP response line and headers must end with CRLF). |
7b825005 | 456 | |
765b4137 DSH |
457 | =item B<-rev> |
458 | ||
8c73aeb6 | 459 | Simple test server which just reverses the text received from the client |
765b4137 DSH |
460 | and sends it back to the server. Also sets B<-brief>. |
461 | ||
5270e702 RL |
462 | =item B<-engine id> |
463 | ||
8c73aeb6 | 464 | Specifying an engine (by its unique B<id> string) will cause B<s_server> |
5270e702 RL |
465 | to attempt to obtain a functional reference to the specified engine, |
466 | thus initialising it if needed. The engine will then be set as the default | |
467 | for all available algorithms. | |
468 | ||
e986704d RL |
469 | =item B<-id_prefix arg> |
470 | ||
8c73aeb6 | 471 | Generate SSL/TLS session IDs prefixed by B<arg>. This is mostly useful |
e986704d RL |
472 | for testing any SSL/TLS code (eg. proxies) that wish to deal with multiple |
473 | servers, when each of which might be generating a unique range of session | |
474 | IDs (eg. with a certain prefix). | |
475 | ||
52b621db LJ |
476 | =item B<-rand file(s)> |
477 | ||
8c73aeb6 | 478 | A file or files containing random data used to seed the random number |
9b86974e | 479 | generator, or an EGD socket (see L<RAND_egd(3)>). |
35ed393e | 480 | Multiple files can be specified separated by an OS-dependent character. |
52b621db LJ |
481 | The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for |
482 | all others. | |
483 | ||
9cd50f73 T |
484 | =item B<-serverinfo file> |
485 | ||
8c73aeb6 | 486 | A file containing one or more blocks of PEM data. Each PEM block |
9cd50f73 T |
487 | must encode a TLS ServerHello extension (2 bytes type, 2 bytes length, |
488 | followed by "length" bytes of extension data). If the client sends | |
489 | an empty TLS ClientHello extension matching the type, the corresponding | |
490 | ServerHello extension will be returned. | |
491 | ||
36086186 SD |
492 | =item B<-no_resumption_on_reneg> |
493 | ||
8c73aeb6 | 494 | Set the B<SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION> option. |
36086186 | 495 | |
cba3f1c7 DSH |
496 | =item B<-status> |
497 | ||
8c73aeb6 | 498 | Enables certificate status request support (aka OCSP stapling). |
cba3f1c7 DSH |
499 | |
500 | =item B<-status_verbose> | |
501 | ||
8c73aeb6 | 502 | Enables certificate status request support (aka OCSP stapling) and gives |
cba3f1c7 DSH |
503 | a verbose printout of the OCSP response. |
504 | ||
505 | =item B<-status_timeout nsec> | |
506 | ||
8c73aeb6 | 507 | Sets the timeout for OCSP response to B<nsec> seconds. |
cba3f1c7 DSH |
508 | |
509 | =item B<-status_url url> | |
510 | ||
8c73aeb6 | 511 | Sets a fallback responder URL to use if no responder URL is present in the |
cba3f1c7 DSH |
512 | server certificate. Without this option an error is returned if the server |
513 | certificate does not contain a responder address. | |
514 | ||
acf65ae5 MC |
515 | =item B<-status_file file> |
516 | ||
517 | Overrides any OCSP responder URLs from the certificate and always provides the | |
518 | OCSP Response stored in the file. The file must be in DER format. | |
519 | ||
776e15f9 | 520 | =item B<-alpn protocols>, B<-nextprotoneg protocols> |
7efd0e77 | 521 | |
776e15f9 RS |
522 | these flags enable the |
523 | Enable the Application-Layer Protocol Negotiation or Next Protocol | |
524 | Negotiation extension, respectively. ALPN is the IETF standard and | |
525 | replaces NPN. | |
526 | The B<protocols> list is a | |
7efd0e77 HK |
527 | comma-separated list of supported protocol names. |
528 | The list should contain most wanted protocols first. | |
529 | Protocol names are printable ASCII strings, for example "http/1.1" or | |
530 | "spdy/3". | |
531 | ||
6437b802 MC |
532 | =item B<-max_early_data> |
533 | ||
534 | Change the default maximum early data bytes that are specified for new sessions | |
535 | and any incoming early data (when used in conjunction with the B<-early_data> | |
536 | flag). The default value is approximately 16k. | |
537 | ||
538 | =item B<-early_data> | |
539 | ||
540 | Accept early data where possible. | |
541 | ||
a2151c5b DSH |
542 | =back |
543 | ||
544 | =head1 CONNECTED COMMANDS | |
545 | ||
546 | If a connection request is established with an SSL client and neither the | |
4b08eaf5 | 547 | B<-www> nor the B<-WWW> option has been used then normally any data received |
8c73aeb6 | 548 | from the client is displayed and any key presses will be sent to the client. |
4b08eaf5 | 549 | |
657e60fa | 550 | Certain single letter commands are also recognized which perform special |
4b08eaf5 DSH |
551 | operations: these are listed below. |
552 | ||
553 | =over 4 | |
554 | ||
555 | =item B<q> | |
556 | ||
557 | end the current SSL connection but still accept new connections. | |
558 | ||
559 | =item B<Q> | |
560 | ||
561 | end the current SSL connection and exit. | |
562 | ||
563 | =item B<r> | |
564 | ||
565 | renegotiate the SSL session. | |
566 | ||
567 | =item B<R> | |
568 | ||
569 | renegotiate the SSL session and request a client certificate. | |
570 | ||
571 | =item B<P> | |
572 | ||
573 | send some plain text down the underlying TCP connection: this should | |
574 | cause the client to disconnect due to a protocol violation. | |
575 | ||
576 | =item B<S> | |
577 | ||
578 | print out some session cache status information. | |
579 | ||
4bf73e9f PW |
580 | =item B<-keylogfile path> |
581 | ||
582 | Appends TLS secrets to the specified keylog file such that external programs | |
583 | (like Wireshark) can decrypt TLS connections. | |
584 | ||
4b08eaf5 | 585 | =back |
a2151c5b DSH |
586 | |
587 | =head1 NOTES | |
588 | ||
589 | B<s_server> can be used to debug SSL clients. To accept connections from | |
590 | a web browser the command: | |
591 | ||
592 | openssl s_server -accept 443 -www | |
593 | ||
594 | can be used for example. | |
595 | ||
596 | Most web browsers (in particular Netscape and MSIE) only support RSA cipher | |
597 | suites, so they cannot connect to servers which don't use a certificate | |
598 | carrying an RSA key or a version of OpenSSL with RSA disabled. | |
599 | ||
600 | Although specifying an empty list of CAs when requesting a client certificate | |
4b08eaf5 DSH |
601 | is strictly speaking a protocol violation, some SSL clients interpret this to |
602 | mean any CA is acceptable. This is useful for debugging purposes. | |
a2151c5b DSH |
603 | |
604 | The session parameters can printed out using the B<sess_id> program. | |
605 | ||
606 | =head1 BUGS | |
607 | ||
8c73aeb6 VD |
608 | Because this program has a lot of options and also because some of the |
609 | techniques used are rather old, the C source of B<s_server> is rather hard to | |
610 | read and not a model of how things should be done. | |
611 | A typical SSL server program would be much simpler. | |
a2151c5b DSH |
612 | |
613 | The output of common ciphers is wrong: it just gives the list of ciphers that | |
4b08eaf5 | 614 | OpenSSL recognizes and the client supports. |
a2151c5b DSH |
615 | |
616 | There should be a way for the B<s_server> program to print out details of any | |
617 | unknown cipher suites a client says it supports. | |
618 | ||
619 | =head1 SEE ALSO | |
620 | ||
6f0ac0e2 | 621 | L<SSL_CONF_cmd(3)>, |
9b86974e | 622 | L<sess_id(1)>, L<s_client(1)>, L<ciphers(1)> |
a2151c5b | 623 | |
fa7b0111 MC |
624 | =head1 HISTORY |
625 | ||
626 | The -no_alt_chains options was first added to OpenSSL 1.1.0. | |
627 | ||
e2f92610 RS |
628 | =head1 COPYRIGHT |
629 | ||
630 | Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved. | |
631 | ||
632 | Licensed under the OpenSSL license (the "License"). You may not use | |
633 | this file except in compliance with the License. You can obtain a copy | |
634 | in the file LICENSE in the source distribution or at | |
635 | L<https://www.openssl.org/source/license.html>. | |
636 | ||
637 | =cut |