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