1S_SERVER(1) OpenSSL S_SERVER(1)
2
6 s_server - SSL/TLS server program
7
9 openssl s_server [-accept port] [-context id] [-verify depth] [-Verify
10 depth] [-crl_check] [-crl_check_all] [-cert filename] [-certform
11 DER|PEM] [-key keyfile] [-keyform DER|PEM] [-pass arg] [-dcert
12 filename] [-dcertform DER|PEM] [-dkey keyfile] [-dkeyform DER|PEM]
13 [-dpass arg] [-dhparam filename] [-nbio] [-nbio_test] [-crlf] [-debug]
14 [-msg] [-state] [-CApath directory] [-CAfile filename] [-nocert]
15 [-cipher cipherlist] [-quiet] [-no_tmp_rsa] [-ssl2] [-ssl3] [-tls1]
16 [-no_ssl2] [-no_ssl3] [-no_tls1] [-no_dhe] [-bugs] [-hack] [-www]
17 [-WWW] [-HTTP] [-engine id] [-tlsextdebug] [-no_ticket] [-id_prefix
18 arg] [-rand file(s)]
19
21 The s_server command implements a generic SSL/TLS server which listens
22 for connections on a given port using SSL/TLS.
23
25 -accept port
26 the TCP port to listen on for connections. If not specified 4433 is
27 used.
28 -context id
30 sets the SSL context id. It can be given any string value. If this
31 option is not present a default value will be used.
32 -cert certname
34 The certificate to use, most servers cipher suites require the use
35 of a certificate and some require a certificate with a certain
36 public key type: for example the DSS cipher suites require a
37 certificate containing a DSS (DSA) key. If not specified then the
38 filename "server.pem" will be used.
39 -certform format
41 The certificate format to use: DER or PEM. PEM is the default.
42 -key keyfile
44 The private key to use. If not specified then the certificate file
45 will be used.
46 -keyform format
48 The private format to use: DER or PEM. PEM is the default.
49 -pass arg
51 the private key password source. For more information about the
52 format of arg see the PASS PHRASE ARGUMENTS section in openssl(1).
53 -dcert filename, -dkey keyname
55 specify an additional certificate and private key, these behave in
56 the same manner as the -cert and -key options except there is no
57 default if they are not specified (no additional certificate and
58 key is used). As noted above some cipher suites require a
59 certificate containing a key of a certain type. Some cipher suites
60 need a certificate carrying an RSA key and some a DSS (DSA) key. By
61 using RSA and DSS certificates and keys a server can support
62 clients which only support RSA or DSS cipher suites by using an
63 appropriate certificate.
64 -dcertform format, -dkeyform format, -dpass arg
66 addtional certificate and private key format and passphrase
67 respectively.
68 -nocert
70 if this option is set then no certificate is used. This restricts
71 the cipher suites available to the anonymous ones (currently just
72 anonymous DH).
73 -dhparam filename
75 the DH parameter file to use. The ephemeral DH cipher suites
76 generate keys using a set of DH parameters. If not specified then
77 an attempt is made to load the parameters from the server
78 certificate file. If this fails then a static set of parameters
79 hard coded into the s_server program will be used.
80 -no_dhe
82 if this option is set then no DH parameters will be loaded
83 effectively disabling the ephemeral DH cipher suites.
84 -no_tmp_rsa
86 certain export cipher suites sometimes use a temporary RSA key,
87 this option disables temporary RSA key generation.
88 -verify depth, -Verify depth
90 The verify depth to use. This specifies the maximum length of the
91 client certificate chain and makes the server request a certificate
92 from the client. With the -verify option a certificate is requested
93 but the client does not have to send one, with the -Verify option
94 the client must supply a certificate or an error occurs.
95 -crl_check, -crl_check_all
97 Check the peer certificate has not been revoked by its CA. The
98 CRL(s) are appended to the certificate file. With the
99 -crl_check_all option all CRLs of all CAs in the chain are checked.
100 -CApath directory
102 The directory to use for client certificate verification. This
103 directory must be in "hash format", see verify for more
104 information. These are also used when building the server
105 certificate chain.
106 -CAfile file
108 A file containing trusted certificates to use during client
109 authentication and to use when attempting to build the server
110 certificate chain. The list is also used in the list of acceptable
111 client CAs passed to the client when a certificate is requested.
112 -state
114 prints out the SSL session states.
115 -debug
117 print extensive debugging information including a hex dump of all
118 traffic.
119 -msg
121 show all protocol messages with hex dump.
122 -nbio_test
124 tests non blocking I/O
125 -nbio
127 turns on non blocking I/O
128 -crlf
130 this option translated a line feed from the terminal into CR+LF.
131 -quiet
133 inhibit printing of session and certificate information.
134 -psk_hint hint
136 Use the PSK identity hint hint when using a PSK cipher suite.
137 -psk key
139 Use the PSK key key when using a PSK cipher suite. The key is given
140 as a hexadecimal number without leading 0x, for example -psk
141 1a2b3c4d.
142 -ssl2, -ssl3, -tls1, -no_ssl2, -no_ssl3, -no_tls1
144 these options disable the use of certain SSL or TLS protocols. By
145 default the initial handshake uses a method which should be
146 compatible with all servers and permit them to use SSL v3, SSL v2
147 or TLS as appropriate.
148 -bugs
150 there are several known bug in SSL and TLS implementations. Adding
151 this option enables various workarounds.
152 -hack
154 this option enables a further workaround for some some early
155 Netscape SSL code (?).
156 -cipher cipherlist
158 this allows the cipher list used by the server to be modified.
159 When the client sends a list of supported ciphers the first client
160 cipher also included in the server list is used. Because the client
161 specifies the preference order, the order of the server cipherlist
162 irrelevant. See the ciphers command for more information.
163 -tlsextdebug
165 print out a hex dump of any TLS extensions received from the
166 server.
167 -no_ticket
169 disable RFC4507bis session ticket support.
170 -www
172 sends a status message back to the client when it connects. This
173 includes lots of information about the ciphers used and various
174 session parameters. The output is in HTML format so this option
175 will normally be used with a web browser.
176 -WWW
178 emulates a simple web server. Pages will be resolved relative to
179 the current directory, for example if the URL
180 https://myhost/page.html is requested the file ./page.html will be
181 loaded.
182 -HTTP
184 emulates a simple web server. Pages will be resolved relative to
185 the current directory, for example if the URL
186 https://myhost/page.html is requested the file ./page.html will be
187 loaded. The files loaded are assumed to contain a complete and
188 correct HTTP response (lines that are part of the HTTP response
189 line and headers must end with CRLF).
190 -engine id
192 specifying an engine (by its unique id string) will cause s_server
193 to attempt to obtain a functional reference to the specified
194 engine, thus initialising it if needed. The engine will then be set
195 as the default for all available algorithms.
196 -id_prefix arg
198 generate SSL/TLS session IDs prefixed by arg. This is mostly useful
199 for testing any SSL/TLS code (eg. proxies) that wish to deal with
200 multiple servers, when each of which might be generating a unique
201 range of session IDs (eg. with a certain prefix).
202 -rand file(s)
204 a file or files containing random data used to seed the random
205 number generator, or an EGD socket (see RAND_egd(3)). Multiple
206 files can be specified separated by a OS-dependent character. The
207 separator is ; for MS-Windows, , for OpenVMS, and : for all others.
208
210 If a connection request is established with an SSL client and neither
211 the -www nor the -WWW option has been used then normally any data
212 received from the client is displayed and any key presses will be sent
213 to the client.
214 Certain single letter commands are also recognized which perform
216 special operations: these are listed below.
217 q end the current SSL connection but still accept new connections.
219 Q end the current SSL connection and exit.
221 r renegotiate the SSL session.
223 R renegotiate the SSL session and request a client certificate.
225 P send some plain text down the underlying TCP connection: this
227 should cause the client to disconnect due to a protocol violation.
228 S print out some session cache status information.
230
232 s_server can be used to debug SSL clients. To accept connections from a
233 web browser the command:
234 openssl s_server -accept 443 -www
236 can be used for example.
238 Most web browsers (in particular Netscape and MSIE) only support RSA
240 cipher suites, so they cannot connect to servers which don't use a
241 certificate carrying an RSA key or a version of OpenSSL with RSA
242 disabled.
243 Although specifying an empty list of CAs when requesting a client
245 certificate is strictly speaking a protocol violation, some SSL clients
246 interpret this to mean any CA is acceptable. This is useful for
247 debugging purposes.
248 The session parameters can printed out using the sess_id program.
250
252 Because this program has a lot of options and also because some of the
253 techniques used are rather old, the C source of s_server is rather hard
254 to read and not a model of how things should be done. A typical SSL
255 server program would be much simpler.
256 The output of common ciphers is wrong: it just gives the list of
258 ciphers that OpenSSL recognizes and the client supports.
259 There should be a way for the s_server program to print out details of
261 any unknown cipher suites a client says it supports.
262
264 sess_id(1), s_client(1), ciphers(1)
2651.0.0e 2009-04-10 S_SERVER(1)