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| <?xml version="1.0"?> | |
| <!DOCTYPE modulesynopsis SYSTEM "../style/modulesynopsis.dtd"> | |
| <?xml-stylesheet type="text/xsl" href="../style/manual.en.xsl"?> | |
| <!-- $LastChangedRevision$ --> | |
| <!-- | |
| Licensed to the Apache Software Foundation (ASF) under one or more | |
| contributor license agreements. See the NOTICE file distributed with | |
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| (the "License"); you may not use this file except in compliance with | |
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| http://www.apache.org/licenses/LICENSE-2.0 | |
| Unless required by applicable law or agreed to in writing, software | |
| distributed under the License is distributed on an "AS IS" BASIS, | |
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| <modulesynopsis metafile="mod_ssl.xml.meta"> | |
| <name>mod_ssl</name> | |
| <description>Strong cryptography using the Secure Sockets | |
| Layer (SSL) and Transport Layer Security (TLS) protocols</description> | |
| <status>Extension</status> | |
| <sourcefile>mod_ssl.c</sourcefile> | |
| <identifier>ssl_module</identifier> | |
| <summary> | |
| <p>This module provides SSL v2/v3 and TLS v1 support for the Apache | |
| HTTP Server. It was contributed by Ralf S. Engelschall based on his | |
| mod_ssl project and originally derived from work by Ben Laurie.</p> | |
| <p>This module relies on <a href="http://www.openssl.org/">OpenSSL</a> | |
| to provide the cryptography engine.</p> | |
| <p>Further details, discussion, and examples are provided in the | |
| <a href="../ssl/">SSL documentation</a>.</p> | |
| </summary> | |
| <section id="envvars"><title>Environment Variables</title> | |
| <p>This module provides a lot of SSL information as additional environment | |
| variables to the SSI and CGI namespace. The generated variables are listed in | |
| the table below. For backward compatibility the information can | |
| be made available under different names, too. Look in the <a | |
| href="../ssl/ssl_compat.html">Compatibility</a> chapter for details on the | |
| compatibility variables.</p> | |
| <table border="1"> | |
| <columnspec><column width=".3"/><column width=".2"/><column width=".5"/> | |
| </columnspec> | |
| <tr> | |
| <th><a name="table3">Variable Name:</a></th> | |
| <th>Value Type:</th> | |
| <th>Description:</th> | |
| </tr> | |
| <tr><td><code>HTTPS</code></td> <td>flag</td> <td>HTTPS is being used.</td></tr> | |
| <tr><td><code>SSL_PROTOCOL</code></td> <td>string</td> <td>The SSL protocol version (SSLv2, SSLv3, TLSv1)</td></tr> | |
| <tr><td><code>SSL_SESSION_ID</code></td> <td>string</td> <td>The hex-encoded SSL session id</td></tr> | |
| <tr><td><code>SSL_SESSION_RESUMED</code></td> <td>string</td> <td>Initial or Resumed SSL Session. Note: multiple requests may be served over the same (Initial or Resumed) SSL session if HTTP KeepAlive is in use</td></tr> | |
| <tr><td><code>SSL_SECURE_RENEG</code></td> <td>string</td> <td><code>true</code> if secure renegotiation is supported, else <code>false</code></td></tr> | |
| <tr><td><code>SSL_CIPHER</code></td> <td>string</td> <td>The cipher specification name</td></tr> | |
| <tr><td><code>SSL_CIPHER_EXPORT</code></td> <td>string</td> <td><code>true</code> if cipher is an export cipher</td></tr> | |
| <tr><td><code>SSL_CIPHER_USEKEYSIZE</code></td> <td>number</td> <td>Number of cipher bits (actually used)</td></tr> | |
| <tr><td><code>SSL_CIPHER_ALGKEYSIZE</code></td> <td>number</td> <td>Number of cipher bits (possible)</td></tr> | |
| <tr><td><code>SSL_COMPRESS_METHOD</code></td> <td>string</td> <td>SSL compression method negotiated</td></tr> | |
| <tr><td><code>SSL_VERSION_INTERFACE</code></td> <td>string</td> <td>The mod_ssl program version</td></tr> | |
| <tr><td><code>SSL_VERSION_LIBRARY</code></td> <td>string</td> <td>The OpenSSL program version</td></tr> | |
| <tr><td><code>SSL_CLIENT_M_VERSION</code></td> <td>string</td> <td>The version of the client certificate</td></tr> | |
| <tr><td><code>SSL_CLIENT_M_SERIAL</code></td> <td>string</td> <td>The serial of the client certificate</td></tr> | |
| <tr><td><code>SSL_CLIENT_S_DN</code></td> <td>string</td> <td>Subject DN in client's certificate</td></tr> | |
| <tr><td><code>SSL_CLIENT_S_DN_</code><em>x509</em></td> <td>string</td> <td>Component of client's Subject DN</td></tr> | |
| <tr><td><code>SSL_CLIENT_I_DN</code></td> <td>string</td> <td>Issuer DN of client's certificate</td></tr> | |
| <tr><td><code>SSL_CLIENT_I_DN_</code><em>x509</em></td> <td>string</td> <td>Component of client's Issuer DN</td></tr> | |
| <tr><td><code>SSL_CLIENT_V_START</code></td> <td>string</td> <td>Validity of client's certificate (start time)</td></tr> | |
| <tr><td><code>SSL_CLIENT_V_END</code></td> <td>string</td> <td>Validity of client's certificate (end time)</td></tr> | |
| <tr><td><code>SSL_CLIENT_V_REMAIN</code></td> <td>string</td> <td>Number of days until client's certificate expires</td></tr> | |
| <tr><td><code>SSL_CLIENT_A_SIG</code></td> <td>string</td> <td>Algorithm used for the signature of client's certificate</td></tr> | |
| <tr><td><code>SSL_CLIENT_A_KEY</code></td> <td>string</td> <td>Algorithm used for the public key of client's certificate</td></tr> | |
| <tr><td><code>SSL_CLIENT_CERT</code></td> <td>string</td> <td>PEM-encoded client certificate</td></tr> | |
| <tr><td><code>SSL_CLIENT_CERT_CHAIN_</code><em>n</em></td> <td>string</td> <td>PEM-encoded certificates in client certificate chain</td></tr> | |
| <tr><td><code>SSL_CLIENT_VERIFY</code></td> <td>string</td> <td><code>NONE</code>, <code>SUCCESS</code>, <code>GENEROUS</code> or <code>FAILED:</code><em>reason</em></td></tr> | |
| <tr><td><code>SSL_SERVER_M_VERSION</code></td> <td>string</td> <td>The version of the server certificate</td></tr> | |
| <tr><td><code>SSL_SERVER_M_SERIAL</code></td> <td>string</td> <td>The serial of the server certificate</td></tr> | |
| <tr><td><code>SSL_SERVER_S_DN</code></td> <td>string</td> <td>Subject DN in server's certificate</td></tr> | |
| <tr><td><code>SSL_SERVER_S_DN_</code><em>x509</em></td> <td>string</td> <td>Component of server's Subject DN</td></tr> | |
| <tr><td><code>SSL_SERVER_I_DN</code></td> <td>string</td> <td>Issuer DN of server's certificate</td></tr> | |
| <tr><td><code>SSL_SERVER_I_DN_</code><em>x509</em></td> <td>string</td> <td>Component of server's Issuer DN</td></tr> | |
| <tr><td><code>SSL_SERVER_V_START</code></td> <td>string</td> <td>Validity of server's certificate (start time)</td></tr> | |
| <tr><td><code>SSL_SERVER_V_END</code></td> <td>string</td> <td>Validity of server's certificate (end time)</td></tr> | |
| <tr><td><code>SSL_SERVER_A_SIG</code></td> <td>string</td> <td>Algorithm used for the signature of server's certificate</td></tr> | |
| <tr><td><code>SSL_SERVER_A_KEY</code></td> <td>string</td> <td>Algorithm used for the public key of server's certificate</td></tr> | |
| <tr><td><code>SSL_SERVER_CERT</code></td> <td>string</td> <td>PEM-encoded server certificate</td></tr> | |
| </table> | |
| <p><em>x509</em> specifies a component of an X.509 DN; one of | |
| <code>C,ST,L,O,OU,CN,T,I,G,S,D,UID,Email</code>. In Apache 2.1 and | |
| later, <em>x509</em> may also include a numeric <code>_n</code> | |
| suffix. If the DN in question contains multiple attributes of the | |
| same name, this suffix is used as an index to select a particular | |
| attribute. For example, where the server certificate subject DN | |
| included two OU fields, <code>SSL_SERVER_S_DN_OU_0</code> and | |
| <code>SSL_SERVER_S_DN_OU_1</code> could be used to reference each.</p> | |
| <p><code>SSL_CLIENT_V_REMAIN</code> is only available in version 2.1 | |
| and later.</p> | |
| <p>A number of additional environment variables can also be used | |
| in <directive>SSLRequire</directive> expressions, or in custom log | |
| formats:</p> | |
| <note><pre>HTTP_USER_AGENT PATH_INFO AUTH_TYPE | |
| HTTP_REFERER QUERY_STRING SERVER_SOFTWARE | |
| HTTP_COOKIE REMOTE_HOST API_VERSION | |
| HTTP_FORWARDED REMOTE_IDENT TIME_YEAR | |
| HTTP_HOST IS_SUBREQ TIME_MON | |
| HTTP_PROXY_CONNECTION DOCUMENT_ROOT TIME_DAY | |
| HTTP_ACCEPT SERVER_ADMIN TIME_HOUR | |
| THE_REQUEST SERVER_NAME TIME_MIN | |
| REQUEST_FILENAME SERVER_PORT TIME_SEC | |
| REQUEST_METHOD SERVER_PROTOCOL TIME_WDAY | |
| REQUEST_SCHEME REMOTE_ADDR TIME | |
| REQUEST_URI REMOTE_USER</pre></note> | |
| <p>In these contexts, two special formats can also be used:</p> | |
| <dl> | |
| <dt><code>ENV:<em>variablename</em></code></dt> | |
| <dd>This will expand to the standard environment | |
| variable <em>variablename</em>.</dd> | |
| <dt><code>HTTP:<em>headername</em></code></dt> | |
| <dd>This will expand to the value of the request header with name | |
| <em>headername</em>.</dd> | |
| </dl> | |
| </section> | |
| <section id="logformats"><title>Custom Log Formats</title> | |
| <p>When <module>mod_ssl</module> is built into Apache or at least | |
| loaded (under DSO situation) additional functions exist for the <a | |
| href="mod_log_config.html#formats">Custom Log Format</a> of | |
| <module>mod_log_config</module>. First there is an | |
| additional ``<code>%{</code><em>varname</em><code>}x</code>'' | |
| eXtension format function which can be used to expand any variables | |
| provided by any module, especially those provided by mod_ssl which can | |
| you find in the above table.</p> | |
| <p> | |
| For backward compatibility there is additionally a special | |
| ``<code>%{</code><em>name</em><code>}c</code>'' cryptography format function | |
| provided. Information about this function is provided in the <a | |
| href="../ssl/ssl_compat.html">Compatibility</a> chapter.</p> | |
| <example><title>Example</title> | |
| CustomLog logs/ssl_request_log \ | |
| "%t %h %{SSL_PROTOCOL}x %{SSL_CIPHER}x \"%r\" %b" | |
| </example> | |
| </section> | |
| <section id="notes"><title>Request Notes</title> | |
| <p><module>mod_ssl</module> sets "notes" for the request which can be | |
| used in logging with the <code>%{<em>name</em>}n</code> format | |
| string in <module>mod_log_config</module>.</p> | |
| <p>The notes supported are as follows:</p> | |
| <dl> | |
| <dt><code>ssl-access-forbidden</code></dt> | |
| <dd>This note is set to the value <code>1</code> if access was | |
| denied due to an <directive>SSLRequire</directive> | |
| or <directive>SSLRequireSSL</directive> directive.</dd> | |
| <dt><code>ssl-secure-reneg</code></dt> | |
| <dd>If <module>mod_ssl</module> is built against a version of | |
| OpenSSL which supports the secure renegotiation extension, this note | |
| is set to the value <code>1</code> if SSL is in used for the current | |
| connection, and the client also supports the secure renegotiation | |
| extension. If the client does not support the secure renegotiation | |
| extension, the note is set to the value <code>0</code>. | |
| If <module>mod_ssl</module> is not built against a version of | |
| OpenSSL which supports secure renegotiation, or if SSL is not in use | |
| for the current connection, the note is not set.</dd> | |
| </dl> | |
| </section> | |
| <section id="authzproviders"><title>Authorization providers for use with Require</title> | |
| <p><module>mod_ssl</module> provides a few authentication providers for use | |
| with <module>mod_authz_core</module>'s | |
| <directive module="mod_authz_core">Require</directive> directive.</p> | |
| <section id="reqssl"><title>Require ssl</title> | |
| <p>The <code>ssl</code> provider denies access if a connection is not | |
| encrypted with SSL. This is similar to the | |
| <directive>SSLRequireSSL</directive> directive.</p> | |
| <example> | |
| Require ssl | |
| </example> | |
| </section> | |
| <section id="reqverifyclient"><title>Require ssl-verify-client</title> | |
| <p>The <code>ssl</code> provider allows access if the user is | |
| authenticated with a valid client certificate. This is only | |
| useful if <code>SSLVerifyClient optional</code> is in effect.</p> | |
| <p>The following example grants access if the user is authenticated | |
| either with a client certificate or by username and password.</p> | |
| <example> | |
| Require ssl-verify-client<br/> | |
| Require valid-user | |
| </example> | |
| </section> | |
| </section> | |
| <directivesynopsis> | |
| <name>SSLPassPhraseDialog</name> | |
| <description>Type of pass phrase dialog for encrypted private | |
| keys</description> | |
| <syntax>SSLPassPhraseDialog <em>type</em></syntax> | |
| <default>SSLPassPhraseDialog builtin</default> | |
| <contextlist><context>server config</context></contextlist> | |
| <usage> | |
| <p> | |
| When Apache starts up it has to read the various Certificate (see | |
| <directive module="mod_ssl">SSLCertificateFile</directive>) and | |
| Private Key (see <directive | |
| module="mod_ssl">SSLCertificateKeyFile</directive>) files of the | |
| SSL-enabled virtual servers. Because for security reasons the Private | |
| Key files are usually encrypted, mod_ssl needs to query the | |
| administrator for a Pass Phrase in order to decrypt those files. This | |
| query can be done in two ways which can be configured by | |
| <em>type</em>:</p> | |
| <ul> | |
| <li><code>builtin</code> | |
| <p> | |
| This is the default where an interactive terminal dialog occurs at startup | |
| time just before Apache detaches from the terminal. Here the administrator | |
| has to manually enter the Pass Phrase for each encrypted Private Key file. | |
| Because a lot of SSL-enabled virtual hosts can be configured, the | |
| following reuse-scheme is used to minimize the dialog: When a Private Key | |
| file is encrypted, all known Pass Phrases (at the beginning there are | |
| none, of course) are tried. If one of those known Pass Phrases succeeds no | |
| dialog pops up for this particular Private Key file. If none succeeded, | |
| another Pass Phrase is queried on the terminal and remembered for the next | |
| round (where it perhaps can be reused).</p> | |
| <p> | |
| This scheme allows mod_ssl to be maximally flexible (because for N encrypted | |
| Private Key files you <em>can</em> use N different Pass Phrases - but then | |
| you have to enter all of them, of course) while minimizing the terminal | |
| dialog (i.e. when you use a single Pass Phrase for all N Private Key files | |
| this Pass Phrase is queried only once).</p></li> | |
| <li><code>|/path/to/program [args...]</code> | |
| <p>This mode allows an external program to be used which acts as a | |
| pipe to a particular input device; the program is sent the standard | |
| prompt text used for the <code>builtin</code> mode on | |
| <code>stdin</code>, and is expected to write password strings on | |
| <code>stdout</code>. If several passwords are needed (or an | |
| incorrect password is entered), additional prompt text will be | |
| written subsequent to the first password being returned, and more | |
| passwords must then be written back.</p></li> | |
| <li><code>exec:/path/to/program</code> | |
| <p> | |
| Here an external program is configured which is called at startup for each | |
| encrypted Private Key file. It is called with two arguments (the first is | |
| of the form ``<code>servername:portnumber</code>'', the second is either | |
| ``<code>RSA</code>'' or ``<code>DSA</code>''), which indicate for which | |
| server and algorithm it has to print the corresponding Pass Phrase to | |
| <code>stdout</code>. The intent is that this external program first runs | |
| security checks to make sure that the system is not compromised by an | |
| attacker, and only when these checks were passed successfully it provides | |
| the Pass Phrase.</p> | |
| <p> | |
| Both these security checks, and the way the Pass Phrase is determined, can | |
| be as complex as you like. Mod_ssl just defines the interface: an | |
| executable program which provides the Pass Phrase on <code>stdout</code>. | |
| Nothing more or less! So, if you're really paranoid about security, here | |
| is your interface. Anything else has to be left as an exercise to the | |
| administrator, because local security requirements are so different.</p> | |
| <p> | |
| The reuse-algorithm above is used here, too. In other words: The external | |
| program is called only once per unique Pass Phrase.</p></li> | |
| </ul> | |
| <example><title>Example</title> | |
| SSLPassPhraseDialog exec:/usr/local/apache/sbin/pp-filter | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLRandomSeed</name> | |
| <description>Pseudo Random Number Generator (PRNG) seeding | |
| source</description> | |
| <syntax>SSLRandomSeed <em>context</em> <em>source</em> | |
| [<em>bytes</em>]</syntax> | |
| <contextlist><context>server config</context></contextlist> | |
| <usage> | |
| <p> | |
| This configures one or more sources for seeding the Pseudo Random Number | |
| Generator (PRNG) in OpenSSL at startup time (<em>context</em> is | |
| <code>startup</code>) and/or just before a new SSL connection is established | |
| (<em>context</em> is <code>connect</code>). This directive can only be used | |
| in the global server context because the PRNG is a global facility.</p> | |
| <p> | |
| The following <em>source</em> variants are available:</p> | |
| <ul> | |
| <li><code>builtin</code> | |
| <p> This is the always available builtin seeding source. It's usage | |
| consumes minimum CPU cycles under runtime and hence can be always used | |
| without drawbacks. The source used for seeding the PRNG contains of the | |
| current time, the current process id and (when applicable) a randomly | |
| chosen 1KB extract of the inter-process scoreboard structure of Apache. | |
| The drawback is that this is not really a strong source and at startup | |
| time (where the scoreboard is still not available) this source just | |
| produces a few bytes of entropy. So you should always, at least for the | |
| startup, use an additional seeding source.</p></li> | |
| <li><code>file:/path/to/source</code> | |
| <p> | |
| This variant uses an external file <code>/path/to/source</code> as the | |
| source for seeding the PRNG. When <em>bytes</em> is specified, only the | |
| first <em>bytes</em> number of bytes of the file form the entropy (and | |
| <em>bytes</em> is given to <code>/path/to/source</code> as the first | |
| argument). When <em>bytes</em> is not specified the whole file forms the | |
| entropy (and <code>0</code> is given to <code>/path/to/source</code> as | |
| the first argument). Use this especially at startup time, for instance | |
| with an available <code>/dev/random</code> and/or | |
| <code>/dev/urandom</code> devices (which usually exist on modern Unix | |
| derivatives like FreeBSD and Linux).</p> | |
| <p> | |
| <em>But be careful</em>: Usually <code>/dev/random</code> provides only as | |
| much entropy data as it actually has, i.e. when you request 512 bytes of | |
| entropy, but the device currently has only 100 bytes available two things | |
| can happen: On some platforms you receive only the 100 bytes while on | |
| other platforms the read blocks until enough bytes are available (which | |
| can take a long time). Here using an existing <code>/dev/urandom</code> is | |
| better, because it never blocks and actually gives the amount of requested | |
| data. The drawback is just that the quality of the received data may not | |
| be the best.</p> | |
| <p> | |
| On some platforms like FreeBSD one can even control how the entropy is | |
| actually generated, i.e. by which system interrupts. More details one can | |
| find under <em>rndcontrol(8)</em> on those platforms. Alternatively, when | |
| your system lacks such a random device, you can use tool | |
| like <a href="http://www.lothar.com/tech/crypto/">EGD</a> | |
| (Entropy Gathering Daemon) and run it's client program with the | |
| <code>exec:/path/to/program/</code> variant (see below) or use | |
| <code>egd:/path/to/egd-socket</code> (see below).</p></li> | |
| <li><code>exec:/path/to/program</code> | |
| <p> | |
| This variant uses an external executable | |
| <code>/path/to/program</code> as the source for seeding the | |
| PRNG. When <em>bytes</em> is specified, only the first | |
| <em>bytes</em> number of bytes of its <code>stdout</code> contents | |
| form the entropy. When <em>bytes</em> is not specified, the | |
| entirety of the data produced on <code>stdout</code> form the | |
| entropy. Use this only at startup time when you need a very strong | |
| seeding with the help of an external program (for instance as in | |
| the example above with the <code>truerand</code> utility you can | |
| find in the mod_ssl distribution which is based on the AT&T | |
| <em>truerand</em> library). Using this in the connection context | |
| slows down the server too dramatically, of course. So usually you | |
| should avoid using external programs in that context.</p></li> | |
| <li><code>egd:/path/to/egd-socket</code> (Unix only) | |
| <p> | |
| This variant uses the Unix domain socket of the | |
| external Entropy Gathering Daemon (EGD) (see <a | |
| href="http://www.lothar.com/tech/crypto/">http://www.lothar.com/tech | |
| /crypto/</a>) to seed the PRNG. Use this if no random device exists | |
| on your platform.</p></li> | |
| </ul> | |
| <example><title>Example</title> | |
| SSLRandomSeed startup builtin<br /> | |
| SSLRandomSeed startup file:/dev/random<br /> | |
| SSLRandomSeed startup file:/dev/urandom 1024<br /> | |
| SSLRandomSeed startup exec:/usr/local/bin/truerand 16<br /> | |
| SSLRandomSeed connect builtin<br /> | |
| SSLRandomSeed connect file:/dev/random<br /> | |
| SSLRandomSeed connect file:/dev/urandom 1024<br /> | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLSessionCache</name> | |
| <description>Type of the global/inter-process SSL Session | |
| Cache</description> | |
| <syntax>SSLSessionCache <em>type</em></syntax> | |
| <default>SSLSessionCache none</default> | |
| <contextlist><context>server config</context></contextlist> | |
| <usage> | |
| <p> | |
| This configures the storage type of the global/inter-process SSL Session | |
| Cache. This cache is an optional facility which speeds up parallel request | |
| processing. For requests to the same server process (via HTTP keep-alive), | |
| OpenSSL already caches the SSL session information locally. But because modern | |
| clients request inlined images and other data via parallel requests (usually | |
| up to four parallel requests are common) those requests are served by | |
| <em>different</em> pre-forked server processes. Here an inter-process cache | |
| helps to avoid unnecessary session handshakes.</p> | |
| <p> | |
| The following four storage <em>type</em>s are currently supported:</p> | |
| <ul> | |
| <li><code>none</code> | |
| <p>This disables the global/inter-process Session Cache. This | |
| will incur a noticeable speed penalty and may cause problems if | |
| using certain browsers, particularly if client certificates are | |
| enabled. This setting is not recommended.</p></li> | |
| <li><code>nonenotnull</code> | |
| <p>This disables any global/inter-process Session Cache. However | |
| it does force OpenSSL to send a non-null session ID to | |
| accommodate buggy clients that require one.</p></li> | |
| <li><code>dbm:/path/to/datafile</code> | |
| <p>This makes use of a DBM hashfile on the local disk to | |
| synchronize the local OpenSSL memory caches of the server | |
| processes. This session cache may suffer reliability issues under | |
| high load.</p></li> | |
| <li><code>shm:/path/to/datafile</code>[<code>(</code><em>size</em><code>)</code>] | |
| <p>This makes use of a high-performance cyclic buffer | |
| (approx. <em>size</em> bytes in size) inside a shared memory | |
| segment in RAM (established via <code>/path/to/datafile</code>) to | |
| synchronize the local OpenSSL memory caches of the server | |
| processes. This is the recommended session cache.</p></li> | |
| <li><code>dc:UNIX:/path/to/socket</code> | |
| <p>This makes use of the <a | |
| href="http://www.distcache.org/">distcache</a> distributed session | |
| caching libraries. The argument should specify the location of | |
| the server or proxy to be used using the distcache address syntax; | |
| for example, <code>UNIX:/path/to/socket</code> specifies a UNIX | |
| domain socket (typically a local dc_client proxy); | |
| <code>IP:server.example.com:9001</code> specifies an IP | |
| address.</p></li> | |
| </ul> | |
| <example><title>Examples</title> | |
| SSLSessionCache dbm:/usr/local/apache/logs/ssl_gcache_data<br /> | |
| SSLSessionCache shm:/usr/local/apache/logs/ssl_gcache_data(512000) | |
| </example> | |
| <p>The <code>ssl-cache</code> mutex is used to serialize access to | |
| the session cache to prevent corruption. This mutex can be configured | |
| using the <directive module="core">Mutex</directive> directive.</p> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLSessionCacheTimeout</name> | |
| <description>Number of seconds before an SSL session expires | |
| in the Session Cache</description> | |
| <syntax>SSLSessionCacheTimeout <em>seconds</em></syntax> | |
| <default>SSLSessionCacheTimeout 300</default> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive sets the timeout in seconds for the information stored in the | |
| global/inter-process SSL Session Cache and the OpenSSL internal memory cache. | |
| It can be set as low as 15 for testing, but should be set to higher | |
| values like 300 in real life.</p> | |
| <example><title>Example</title> | |
| SSLSessionCacheTimeout 600 | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLEngine</name> | |
| <description>SSL Engine Operation Switch</description> | |
| <syntax>SSLEngine on|off|optional</syntax> | |
| <default>SSLEngine off</default> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive toggles the usage of the SSL/TLS Protocol Engine. This | |
| is usually used inside a <directive module="core" | |
| type="section">VirtualHost</directive> section to enable SSL/TLS for a | |
| particular virtual host. By default the SSL/TLS Protocol Engine is | |
| disabled for both the main server and all configured virtual hosts.</p> | |
| <example><title>Example</title> | |
| <VirtualHost _default_:443><br /> | |
| SSLEngine on<br /> | |
| ...<br /> | |
| </VirtualHost> | |
| </example> | |
| <p>In Apache 2.1 and later, <directive>SSLEngine</directive> can be set to | |
| <code>optional</code>. This enables support for | |
| <a href="http://www.ietf.org/rfc/rfc2817.txt">RFC 2817</a>, Upgrading to TLS | |
| Within HTTP/1.1. At this time no web browsers support RFC 2817.</p> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLFIPS</name> | |
| <description>SSL FIPS mode Switch</description> | |
| <syntax>SSLFIPS on|off</syntax> | |
| <default>SSLFIPS off</default> | |
| <contextlist><context>server config</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive toggles the usage of the SSL library FIPS_mode flag. | |
| It must be set in the global server context and cannot be configured | |
| with conflicting settings (SSLFIPS on followed by SSLFIPS off or | |
| similar). The mode applies to all SSL library operations. | |
| </p> | |
| <p> | |
| If httpd was compiled against an SSL library which did not support | |
| the FIPS_mode flag, <code>SSLFIPS on</code> will fail. Refer to the | |
| FIPS 140-2 Security Policy document of the SSL provider library for | |
| specific requirements to use mod_ssl in a FIPS 140-2 approved mode | |
| of operation; note that mod_ssl itself is not validated, but may be | |
| described as using FIPS 140-2 validated cryptographic module, when | |
| all components are assembled and operated under the guidelines imposed | |
| by the applicable Security Policy. | |
| </p> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLProtocol</name> | |
| <description>Configure usable SSL protocol versions</description> | |
| <syntax>SSLProtocol [+|-]<em>protocol</em> ...</syntax> | |
| <default>SSLProtocol all</default> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive can be used to control which versions of the SSL protocol | |
| will be accepted in new connections.</p> | |
| <p> | |
| The available (case-insensitive) <em>protocol</em>s are:</p> | |
| <ul> | |
| <li><code>SSLv2</code> | |
| <p> | |
| This is the Secure Sockets Layer (SSL) protocol, version 2.0. It is the | |
| original SSL protocol as designed by Netscape Corporation. Though it's | |
| use has been deprecated, because of weaknesses in the security of the protocol.</p></li> | |
| <li><code>SSLv3</code> | |
| <p> | |
| This is the Secure Sockets Layer (SSL) protocol, version 3.0, from | |
| the Netscape Corporation. | |
| It is the successor to SSLv2 and the predecessor to TLSv1. It's supported by | |
| almost all popular browsers.</p></li> | |
| <li><code>TLSv1</code> | |
| <p> | |
| This is the Transport Layer Security (TLS) protocol, version 1.0. It is the | |
| successor to SSLv3 and is defined in <a href="http://www.ietf.org/rfc/rfc2246.txt">RFC2246</a>. | |
| Which has been obsoleted by <a href="http://www.ietf.org/rfc/rfc4346.txt">RFC4346</a>.</p></li> | |
| <li><code>All</code> | |
| <p> | |
| This is a shortcut for ``<code>+SSLv2 +SSLv3 +TLSv1</code>'' and a | |
| convenient way for enabling all protocols except one when used in | |
| combination with the minus sign on a protocol as the example above | |
| shows.</p></li> | |
| </ul> | |
| <example><title>Example</title> | |
| # enable SSLv3 and TLSv1, but not SSLv2<br /> | |
| SSLProtocol all -SSLv2 | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLCipherSuite</name> | |
| <description>Cipher Suite available for negotiation in SSL | |
| handshake</description> | |
| <syntax>SSLCipherSuite <em>cipher-spec</em></syntax> | |
| <default>SSLCipherSuite ALL:!ADH:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv2:+EXP</default> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context> | |
| <context>directory</context> | |
| <context>.htaccess</context></contextlist> | |
| <override>AuthConfig</override> | |
| <usage> | |
| <p> | |
| This complex directive uses a colon-separated <em>cipher-spec</em> string | |
| consisting of OpenSSL cipher specifications to configure the Cipher Suite the | |
| client is permitted to negotiate in the SSL handshake phase. Notice that this | |
| directive can be used both in per-server and per-directory context. In | |
| per-server context it applies to the standard SSL handshake when a connection | |
| is established. In per-directory context it forces a SSL renegotiation with the | |
| reconfigured Cipher Suite after the HTTP request was read but before the HTTP | |
| response is sent.</p> | |
| <p> | |
| An SSL cipher specification in <em>cipher-spec</em> is composed of 4 major | |
| attributes plus a few extra minor ones:</p> | |
| <ul> | |
| <li><em>Key Exchange Algorithm</em>:<br /> | |
| RSA or Diffie-Hellman variants. | |
| </li> | |
| <li><em>Authentication Algorithm</em>:<br /> | |
| RSA, Diffie-Hellman, DSS or none. | |
| </li> | |
| <li><em>Cipher/Encryption Algorithm</em>:<br /> | |
| DES, Triple-DES, RC4, RC2, IDEA or none. | |
| </li> | |
| <li><em>MAC Digest Algorithm</em>:<br /> | |
| MD5, SHA or SHA1. | |
| </li> | |
| </ul> | |
| <p>An SSL cipher can also be an export cipher and is either an SSLv2 or SSLv3/TLSv1 | |
| cipher (here TLSv1 is equivalent to SSLv3). To specify which ciphers to use, | |
| one can either specify all the Ciphers, one at a time, or use aliases to | |
| specify the preference and order for the ciphers (see <a href="#table1">Table | |
| 1</a>).</p> | |
| <table border="1"> | |
| <columnspec><column width=".5"/><column width=".5"/></columnspec> | |
| <tr><th><a name="table1">Tag</a></th> <th>Description</th></tr> | |
| <tr><td colspan="2"><em>Key Exchange Algorithm:</em></td></tr> | |
| <tr><td><code>kRSA</code></td> <td>RSA key exchange</td></tr> | |
| <tr><td><code>kDHr</code></td> <td>Diffie-Hellman key exchange with RSA key</td></tr> | |
| <tr><td><code>kDHd</code></td> <td>Diffie-Hellman key exchange with DSA key</td></tr> | |
| <tr><td><code>kEDH</code></td> <td>Ephemeral (temp.key) Diffie-Hellman key exchange (no cert)</td> </tr> | |
| <tr><td colspan="2"><em>Authentication Algorithm:</em></td></tr> | |
| <tr><td><code>aNULL</code></td> <td>No authentication</td></tr> | |
| <tr><td><code>aRSA</code></td> <td>RSA authentication</td></tr> | |
| <tr><td><code>aDSS</code></td> <td>DSS authentication</td> </tr> | |
| <tr><td><code>aDH</code></td> <td>Diffie-Hellman authentication</td></tr> | |
| <tr><td colspan="2"><em>Cipher Encoding Algorithm:</em></td></tr> | |
| <tr><td><code>eNULL</code></td> <td>No encoding</td> </tr> | |
| <tr><td><code>DES</code></td> <td>DES encoding</td> </tr> | |
| <tr><td><code>3DES</code></td> <td>Triple-DES encoding</td> </tr> | |
| <tr><td><code>RC4</code></td> <td>RC4 encoding</td> </tr> | |
| <tr><td><code>RC2</code></td> <td>RC2 encoding</td> </tr> | |
| <tr><td><code>IDEA</code></td> <td>IDEA encoding</td> </tr> | |
| <tr><td colspan="2"><em>MAC Digest Algorithm</em>:</td></tr> | |
| <tr><td><code>MD5</code></td> <td>MD5 hash function</td></tr> | |
| <tr><td><code>SHA1</code></td> <td>SHA1 hash function</td></tr> | |
| <tr><td><code>SHA</code></td> <td>SHA hash function</td> </tr> | |
| <tr><td colspan="2"><em>Aliases:</em></td></tr> | |
| <tr><td><code>SSLv2</code></td> <td>all SSL version 2.0 ciphers</td></tr> | |
| <tr><td><code>SSLv3</code></td> <td>all SSL version 3.0 ciphers</td> </tr> | |
| <tr><td><code>TLSv1</code></td> <td>all TLS version 1.0 ciphers</td> </tr> | |
| <tr><td><code>EXP</code></td> <td>all export ciphers</td> </tr> | |
| <tr><td><code>EXPORT40</code></td> <td>all 40-bit export ciphers only</td> </tr> | |
| <tr><td><code>EXPORT56</code></td> <td>all 56-bit export ciphers only</td> </tr> | |
| <tr><td><code>LOW</code></td> <td>all low strength ciphers (no export, single DES)</td></tr> | |
| <tr><td><code>MEDIUM</code></td> <td>all ciphers with 128 bit encryption</td> </tr> | |
| <tr><td><code>HIGH</code></td> <td>all ciphers using Triple-DES</td> </tr> | |
| <tr><td><code>RSA</code></td> <td>all ciphers using RSA key exchange</td> </tr> | |
| <tr><td><code>DH</code></td> <td>all ciphers using Diffie-Hellman key exchange</td> </tr> | |
| <tr><td><code>EDH</code></td> <td>all ciphers using Ephemeral Diffie-Hellman key exchange</td> </tr> | |
| <tr><td><code>ADH</code></td> <td>all ciphers using Anonymous Diffie-Hellman key exchange</td> </tr> | |
| <tr><td><code>DSS</code></td> <td>all ciphers using DSS authentication</td> </tr> | |
| <tr><td><code>NULL</code></td> <td>all ciphers using no encryption</td> </tr> | |
| </table> | |
| <p> | |
| Now where this becomes interesting is that these can be put together | |
| to specify the order and ciphers you wish to use. To speed this up | |
| there are also aliases (<code>SSLv2, SSLv3, TLSv1, EXP, LOW, MEDIUM, | |
| HIGH</code>) for certain groups of ciphers. These tags can be joined | |
| together with prefixes to form the <em>cipher-spec</em>. Available | |
| prefixes are:</p> | |
| <ul> | |
| <li>none: add cipher to list</li> | |
| <li><code>+</code>: add ciphers to list and pull them to current location in list</li> | |
| <li><code>-</code>: remove cipher from list (can be added later again)</li> | |
| <li><code>!</code>: kill cipher from list completely (can <strong>not</strong> be added later again)</li> | |
| </ul> | |
| <p>A simpler way to look at all of this is to use the ``<code>openssl ciphers | |
| -v</code>'' command which provides a nice way to successively create the | |
| correct <em>cipher-spec</em> string. The default <em>cipher-spec</em> string | |
| is ``<code>ALL:!ADH:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv2:+EXP</code>'' which | |
| means the following: first, remove from consideration any ciphers that do not | |
| authenticate, i.e. for SSL only the Anonymous Diffie-Hellman ciphers. Next, | |
| use ciphers using RC4 and RSA. Next include the high, medium and then the low | |
| security ciphers. Finally <em>pull</em> all SSLv2 and export ciphers to the | |
| end of the list.</p> | |
| <example> | |
| <pre> | |
| $ openssl ciphers -v 'ALL:!ADH:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv2:+EXP' | |
| NULL-SHA SSLv3 Kx=RSA Au=RSA Enc=None Mac=SHA1 | |
| NULL-MD5 SSLv3 Kx=RSA Au=RSA Enc=None Mac=MD5 | |
| EDH-RSA-DES-CBC3-SHA SSLv3 Kx=DH Au=RSA Enc=3DES(168) Mac=SHA1 | |
| ... ... ... ... ... | |
| EXP-RC4-MD5 SSLv3 Kx=RSA(512) Au=RSA Enc=RC4(40) Mac=MD5 export | |
| EXP-RC2-CBC-MD5 SSLv2 Kx=RSA(512) Au=RSA Enc=RC2(40) Mac=MD5 export | |
| EXP-RC4-MD5 SSLv2 Kx=RSA(512) Au=RSA Enc=RC4(40) Mac=MD5 export | |
| </pre> | |
| </example> | |
| <p>The complete list of particular RSA & DH ciphers for SSL is given in <a | |
| href="#table2">Table 2</a>.</p> | |
| <example><title>Example</title> | |
| SSLCipherSuite RSA:!EXP:!NULL:+HIGH:+MEDIUM:-LOW | |
| </example> | |
| <table border="1"> | |
| <columnspec><column width=".3"/><column width=".1"/><column width=".13"/> | |
| <column width=".1"/><column width=".13"/><column width=".1"/> | |
| <column width=".13"/></columnspec> | |
| <tr><th><a name="table2">Cipher-Tag</a></th> <th>Protocol</th> <th>Key Ex.</th> <th>Auth.</th> <th>Enc.</th> <th>MAC</th> <th>Type</th> </tr> | |
| <tr><td colspan="7"><em>RSA Ciphers:</em></td></tr> | |
| <tr><td><code>DES-CBC3-SHA</code></td> <td>SSLv3</td> <td>RSA</td> <td>RSA</td> <td>3DES(168)</td> <td>SHA1</td> <td></td> </tr> | |
| <tr><td><code>DES-CBC3-MD5</code></td> <td>SSLv2</td> <td>RSA</td> <td>RSA</td> <td>3DES(168)</td> <td>MD5</td> <td></td> </tr> | |
| <tr><td><code>IDEA-CBC-SHA</code></td> <td>SSLv3</td> <td>RSA</td> <td>RSA</td> <td>IDEA(128)</td> <td>SHA1</td> <td></td> </tr> | |
| <tr><td><code>RC4-SHA</code></td> <td>SSLv3</td> <td>RSA</td> <td>RSA</td> <td>RC4(128)</td> <td>SHA1</td> <td></td> </tr> | |
| <tr><td><code>RC4-MD5</code></td> <td>SSLv3</td> <td>RSA</td> <td>RSA</td> <td>RC4(128)</td> <td>MD5</td> <td></td> </tr> | |
| <tr><td><code>IDEA-CBC-MD5</code></td> <td>SSLv2</td> <td>RSA</td> <td>RSA</td> <td>IDEA(128)</td> <td>MD5</td> <td></td> </tr> | |
| <tr><td><code>RC2-CBC-MD5</code></td> <td>SSLv2</td> <td>RSA</td> <td>RSA</td> <td>RC2(128)</td> <td>MD5</td> <td></td> </tr> | |
| <tr><td><code>RC4-MD5</code></td> <td>SSLv2</td> <td>RSA</td> <td>RSA</td> <td>RC4(128)</td> <td>MD5</td> <td></td> </tr> | |
| <tr><td><code>DES-CBC-SHA</code></td> <td>SSLv3</td> <td>RSA</td> <td>RSA</td> <td>DES(56)</td> <td>SHA1</td> <td></td> </tr> | |
| <tr><td><code>RC4-64-MD5</code></td> <td>SSLv2</td> <td>RSA</td> <td>RSA</td> <td>RC4(64)</td> <td>MD5</td> <td></td> </tr> | |
| <tr><td><code>DES-CBC-MD5</code></td> <td>SSLv2</td> <td>RSA</td> <td>RSA</td> <td>DES(56)</td> <td>MD5</td> <td></td> </tr> | |
| <tr><td><code>EXP-DES-CBC-SHA</code></td> <td>SSLv3</td> <td>RSA(512)</td> <td>RSA</td> <td>DES(40)</td> <td>SHA1</td> <td> export</td> </tr> | |
| <tr><td><code>EXP-RC2-CBC-MD5</code></td> <td>SSLv3</td> <td>RSA(512)</td> <td>RSA</td> <td>RC2(40)</td> <td>MD5</td> <td> export</td> </tr> | |
| <tr><td><code>EXP-RC4-MD5</code></td> <td>SSLv3</td> <td>RSA(512)</td> <td>RSA</td> <td>RC4(40)</td> <td>MD5</td> <td> export</td> </tr> | |
| <tr><td><code>EXP-RC2-CBC-MD5</code></td> <td>SSLv2</td> <td>RSA(512)</td> <td>RSA</td> <td>RC2(40)</td> <td>MD5</td> <td> export</td> </tr> | |
| <tr><td><code>EXP-RC4-MD5</code></td> <td>SSLv2</td> <td>RSA(512)</td> <td>RSA</td> <td>RC4(40)</td> <td>MD5</td> <td> export</td> </tr> | |
| <tr><td><code>NULL-SHA</code></td> <td>SSLv3</td> <td>RSA</td> <td>RSA</td> <td>None</td> <td>SHA1</td> <td></td> </tr> | |
| <tr><td><code>NULL-MD5</code></td> <td>SSLv3</td> <td>RSA</td> <td>RSA</td> <td>None</td> <td>MD5</td> <td></td> </tr> | |
| <tr><td colspan="7"><em>Diffie-Hellman Ciphers:</em></td></tr> | |
| <tr><td><code>ADH-DES-CBC3-SHA</code></td> <td>SSLv3</td> <td>DH</td> <td>None</td> <td>3DES(168)</td> <td>SHA1</td> <td></td> </tr> | |
| <tr><td><code>ADH-DES-CBC-SHA</code></td> <td>SSLv3</td> <td>DH</td> <td>None</td> <td>DES(56)</td> <td>SHA1</td> <td></td> </tr> | |
| <tr><td><code>ADH-RC4-MD5</code></td> <td>SSLv3</td> <td>DH</td> <td>None</td> <td>RC4(128)</td> <td>MD5</td> <td></td> </tr> | |
| <tr><td><code>EDH-RSA-DES-CBC3-SHA</code></td> <td>SSLv3</td> <td>DH</td> <td>RSA</td> <td>3DES(168)</td> <td>SHA1</td> <td></td> </tr> | |
| <tr><td><code>EDH-DSS-DES-CBC3-SHA</code></td> <td>SSLv3</td> <td>DH</td> <td>DSS</td> <td>3DES(168)</td> <td>SHA1</td> <td></td> </tr> | |
| <tr><td><code>EDH-RSA-DES-CBC-SHA</code></td> <td>SSLv3</td> <td>DH</td> <td>RSA</td> <td>DES(56)</td> <td>SHA1</td> <td></td> </tr> | |
| <tr><td><code>EDH-DSS-DES-CBC-SHA</code></td> <td>SSLv3</td> <td>DH</td> <td>DSS</td> <td>DES(56)</td> <td>SHA1</td> <td></td> </tr> | |
| <tr><td><code>EXP-EDH-RSA-DES-CBC-SHA</code></td> <td>SSLv3</td> <td>DH(512)</td> <td>RSA</td> <td>DES(40)</td> <td>SHA1</td> <td> export</td> </tr> | |
| <tr><td><code>EXP-EDH-DSS-DES-CBC-SHA</code></td> <td>SSLv3</td> <td>DH(512)</td> <td>DSS</td> <td>DES(40)</td> <td>SHA1</td> <td> export</td> </tr> | |
| <tr><td><code>EXP-ADH-DES-CBC-SHA</code></td> <td>SSLv3</td> <td>DH(512)</td> <td>None</td> <td>DES(40)</td> <td>SHA1</td> <td> export</td> </tr> | |
| <tr><td><code>EXP-ADH-RC4-MD5</code></td> <td>SSLv3</td> <td>DH(512)</td> <td>None</td> <td>RC4(40)</td> <td>MD5</td> <td> export</td> </tr> | |
| </table> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLCertificateFile</name> | |
| <description>Server PEM-encoded X.509 Certificate file</description> | |
| <syntax>SSLCertificateFile <em>file-path</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive points to the PEM-encoded Certificate file for the server and | |
| optionally also to the corresponding RSA or DSA Private Key file for it | |
| (contained in the same file). If the contained Private Key is encrypted the | |
| Pass Phrase dialog is forced at startup time. This directive can be used up to | |
| two times (referencing different filenames) when both a RSA and a DSA based | |
| server certificate is used in parallel.</p> | |
| <example><title>Example</title> | |
| SSLCertificateFile /usr/local/apache2/conf/ssl.crt/server.crt | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLCertificateKeyFile</name> | |
| <description>Server PEM-encoded Private Key file</description> | |
| <syntax>SSLCertificateKeyFile <em>file-path</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive points to the PEM-encoded Private Key file for the | |
| server. If the Private Key is not combined with the Certificate in the | |
| <directive>SSLCertificateFile</directive>, use this additional directive to | |
| point to the file with the stand-alone Private Key. When | |
| <directive>SSLCertificateFile</directive> is used and the file | |
| contains both the Certificate and the Private Key this directive need | |
| not be used. But we strongly discourage this practice. Instead we | |
| recommend you to separate the Certificate and the Private Key. If the | |
| contained Private Key is encrypted, the Pass Phrase dialog is forced | |
| at startup time. This directive can be used up to two times | |
| (referencing different filenames) when both a RSA and a DSA based | |
| private key is used in parallel.</p> | |
| <example><title>Example</title> | |
| SSLCertificateKeyFile /usr/local/apache2/conf/ssl.key/server.key | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLCertificateChainFile</name> | |
| <description>File of PEM-encoded Server CA Certificates</description> | |
| <syntax>SSLCertificateChainFile <em>file-path</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive sets the optional <em>all-in-one</em> file where you can | |
| assemble the certificates of Certification Authorities (CA) which form the | |
| certificate chain of the server certificate. This starts with the issuing CA | |
| certificate of the server certificate and can range up to the root CA | |
| certificate. Such a file is simply the concatenation of the various | |
| PEM-encoded CA Certificate files, usually in certificate chain order.</p> | |
| <p> | |
| This should be used alternatively and/or additionally to <directive | |
| module="mod_ssl">SSLCACertificatePath</directive> for explicitly | |
| constructing the server certificate chain which is sent to the browser | |
| in addition to the server certificate. It is especially useful to | |
| avoid conflicts with CA certificates when using client | |
| authentication. Because although placing a CA certificate of the | |
| server certificate chain into <directive | |
| module="mod_ssl">SSLCACertificatePath</directive> has the same effect | |
| for the certificate chain construction, it has the side-effect that | |
| client certificates issued by this same CA certificate are also | |
| accepted on client authentication.</p> | |
| <p> | |
| But be careful: Providing the certificate chain works only if you are using a | |
| <em>single</em> RSA <em>or</em> DSA based server certificate. If you are | |
| using a coupled RSA+DSA certificate pair, this will work only if actually both | |
| certificates use the <em>same</em> certificate chain. Else the browsers will be | |
| confused in this situation.</p> | |
| <example><title>Example</title> | |
| SSLCertificateChainFile /usr/local/apache2/conf/ssl.crt/ca.crt | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLCACertificatePath</name> | |
| <description>Directory of PEM-encoded CA Certificates for | |
| Client Auth</description> | |
| <syntax>SSLCACertificatePath <em>directory-path</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive sets the directory where you keep the Certificates of | |
| Certification Authorities (CAs) whose clients you deal with. These are used to | |
| verify the client certificate on Client Authentication.</p> | |
| <p> | |
| The files in this directory have to be PEM-encoded and are accessed through | |
| hash filenames. So usually you can't just place the Certificate files | |
| there: you also have to create symbolic links named | |
| <em>hash-value</em><code>.N</code>. And you should always make sure this directory | |
| contains the appropriate symbolic links. Use the <code>Makefile</code> which | |
| comes with mod_ssl to accomplish this task.</p> | |
| <example><title>Example</title> | |
| SSLCACertificatePath /usr/local/apache2/conf/ssl.crt/ | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLCACertificateFile</name> | |
| <description>File of concatenated PEM-encoded CA Certificates | |
| for Client Auth</description> | |
| <syntax>SSLCACertificateFile <em>file-path</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive sets the <em>all-in-one</em> file where you can assemble the | |
| Certificates of Certification Authorities (CA) whose <em>clients</em> you deal | |
| with. These are used for Client Authentication. Such a file is simply the | |
| concatenation of the various PEM-encoded Certificate files, in order of | |
| preference. This can be used alternatively and/or additionally to | |
| <directive module="mod_ssl">SSLCACertificatePath</directive>.</p> | |
| <example><title>Example</title> | |
| SSLCACertificateFile /usr/local/apache2/conf/ssl.crt/ca-bundle-client.crt | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLCADNRequestFile</name> | |
| <description>File of concatenated PEM-encoded CA Certificates | |
| for defining acceptable CA names</description> | |
| <syntax>SSLCADNRequestFile <em>file-path</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p>When a client certificate is requested by mod_ssl, a list of | |
| <em>acceptable Certificate Authority names</em> is sent to the client | |
| in the SSL handshake. These CA names can be used by the client to | |
| select an appropriate client certificate out of those it has | |
| available.</p> | |
| <p>If neither of the directives <directive | |
| module="mod_ssl">SSLCADNRequestPath</directive> or <directive | |
| module="mod_ssl">SSLCADNRequestFile</directive> are given, then the | |
| set of acceptable CA names sent to the client is the names of all the | |
| CA certificates given by the <directive | |
| module="mod_ssl">SSLCACertificateFile</directive> and <directive | |
| module="mod_ssl">SSLCACertificatePath</directive> directives; in other | |
| words, the names of the CAs which will actually be used to verify the | |
| client certificate.</p> | |
| <p>In some circumstances, it is useful to be able to send a set of | |
| acceptable CA names which differs from the actual CAs used to verify | |
| the client certificate - for example, if the client certificates are | |
| signed by intermediate CAs. In such cases, <directive | |
| module="mod_ssl">SSLCADNRequestPath</directive> and/or <directive | |
| module="mod_ssl">SSLCADNRequestFile</directive> can be used; the | |
| acceptable CA names are then taken from the complete set of | |
| certificates in the directory and/or file specified by this pair of | |
| directives.</p> | |
| <p><directive module="mod_ssl">SSLCADNRequestFile</directive> must | |
| specify an <em>all-in-one</em> file containing a concatenation of | |
| PEM-encoded CA certificates.</p> | |
| <example><title>Example</title> | |
| SSLCADNRequestFile /usr/local/apache2/conf/ca-names.crt | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLCADNRequestPath</name> | |
| <description>Directory of PEM-encoded CA Certificates for | |
| defining acceptable CA names</description> | |
| <syntax>SSLCADNRequestPath <em>directory-path</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p>This optional directive can be used to specify the set of | |
| <em>acceptable CA names</em> which will be sent to the client when a | |
| client certificate is requested. See the <directive | |
| module="mod_ssl">SSLCADNRequestFile</directive> directive for more | |
| details.</p> | |
| <p>The files in this directory have to be PEM-encoded and are accessed | |
| through hash filenames. So usually you can't just place the | |
| Certificate files there: you also have to create symbolic links named | |
| <em>hash-value</em><code>.N</code>. And you should always make sure | |
| this directory contains the appropriate symbolic links. Use the | |
| <code>Makefile</code> which comes with mod_ssl to accomplish this | |
| task.</p> | |
| <example><title>Example</title> | |
| SSLCADNRequestPath /usr/local/apache2/conf/ca-names.crt/ | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLCARevocationPath</name> | |
| <description>Directory of PEM-encoded CA CRLs for | |
| Client Auth</description> | |
| <syntax>SSLCARevocationPath <em>directory-path</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive sets the directory where you keep the Certificate Revocation | |
| Lists (CRL) of Certification Authorities (CAs) whose clients you deal with. | |
| These are used to revoke the client certificate on Client Authentication.</p> | |
| <p> | |
| The files in this directory have to be PEM-encoded and are accessed through | |
| hash filenames. So usually you have not only to place the CRL files there. | |
| Additionally you have to create symbolic links named | |
| <em>hash-value</em><code>.rN</code>. And you should always make sure this directory | |
| contains the appropriate symbolic links. Use the <code>Makefile</code> which | |
| comes with <module>mod_ssl</module> to accomplish this task.</p> | |
| <example><title>Example</title> | |
| SSLCARevocationPath /usr/local/apache2/conf/ssl.crl/ | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLCARevocationFile</name> | |
| <description>File of concatenated PEM-encoded CA CRLs for | |
| Client Auth</description> | |
| <syntax>SSLCARevocationFile <em>file-path</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive sets the <em>all-in-one</em> file where you can | |
| assemble the Certificate Revocation Lists (CRL) of Certification | |
| Authorities (CA) whose <em>clients</em> you deal with. These are used | |
| for Client Authentication. Such a file is simply the concatenation of | |
| the various PEM-encoded CRL files, in order of preference. This can be | |
| used alternatively and/or additionally to <directive | |
| module="mod_ssl">SSLCARevocationPath</directive>.</p> | |
| <example><title>Example</title> | |
| SSLCARevocationFile /usr/local/apache2/conf/ssl.crl/ca-bundle-client.crl | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLVerifyClient</name> | |
| <description>Type of Client Certificate verification</description> | |
| <syntax>SSLVerifyClient <em>level</em></syntax> | |
| <default>SSLVerifyClient none</default> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context> | |
| <context>directory</context> | |
| <context>.htaccess</context></contextlist> | |
| <override>AuthConfig</override> | |
| <usage> | |
| <p> | |
| This directive sets the Certificate verification level for the Client | |
| Authentication. Notice that this directive can be used both in per-server and | |
| per-directory context. In per-server context it applies to the client | |
| authentication process used in the standard SSL handshake when a connection is | |
| established. In per-directory context it forces a SSL renegotiation with the | |
| reconfigured client verification level after the HTTP request was read but | |
| before the HTTP response is sent.</p> | |
| <p> | |
| The following levels are available for <em>level</em>:</p> | |
| <ul> | |
| <li><strong>none</strong>: | |
| no client Certificate is required at all</li> | |
| <li><strong>optional</strong>: | |
| the client <em>may</em> present a valid Certificate</li> | |
| <li><strong>require</strong>: | |
| the client <em>has to</em> present a valid Certificate</li> | |
| <li><strong>optional_no_ca</strong>: | |
| the client may present a valid Certificate<br /> | |
| but it need not to be (successfully) verifiable.</li> | |
| </ul> | |
| <p>In practice only levels <strong>none</strong> and | |
| <strong>require</strong> are really interesting, because level | |
| <strong>optional</strong> doesn't work with all browsers and level | |
| <strong>optional_no_ca</strong> is actually against the idea of | |
| authentication (but can be used to establish SSL test pages, etc.)</p> | |
| <example><title>Example</title> | |
| SSLVerifyClient require | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLVerifyDepth</name> | |
| <description>Maximum depth of CA Certificates in Client | |
| Certificate verification</description> | |
| <syntax>SSLVerifyDepth <em>number</em></syntax> | |
| <default>SSLVerifyDepth 1</default> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context> | |
| <context>directory</context> | |
| <context>.htaccess</context></contextlist> | |
| <override>AuthConfig</override> | |
| <usage> | |
| <p> | |
| This directive sets how deeply mod_ssl should verify before deciding that the | |
| clients don't have a valid certificate. Notice that this directive can be | |
| used both in per-server and per-directory context. In per-server context it | |
| applies to the client authentication process used in the standard SSL | |
| handshake when a connection is established. In per-directory context it forces | |
| a SSL renegotiation with the reconfigured client verification depth after the | |
| HTTP request was read but before the HTTP response is sent.</p> | |
| <p> | |
| The depth actually is the maximum number of intermediate certificate issuers, | |
| i.e. the number of CA certificates which are max allowed to be followed while | |
| verifying the client certificate. A depth of 0 means that self-signed client | |
| certificates are accepted only, the default depth of 1 means the client | |
| certificate can be self-signed or has to be signed by a CA which is directly | |
| known to the server (i.e. the CA's certificate is under | |
| <directive module="mod_ssl">SSLCACertificatePath</directive>), etc.</p> | |
| <example><title>Example</title> | |
| SSLVerifyDepth 10 | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLOptions</name> | |
| <description>Configure various SSL engine run-time options</description> | |
| <syntax>SSLOptions [+|-]<em>option</em> ...</syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context> | |
| <context>directory</context> | |
| <context>.htaccess</context></contextlist> | |
| <override>Options</override> | |
| <usage> | |
| <p> | |
| This directive can be used to control various run-time options on a | |
| per-directory basis. Normally, if multiple <code>SSLOptions</code> | |
| could apply to a directory, then the most specific one is taken | |
| completely; the options are not merged. However if <em>all</em> the | |
| options on the <code>SSLOptions</code> directive are preceded by a | |
| plus (<code>+</code>) or minus (<code>-</code>) symbol, the options | |
| are merged. Any options preceded by a <code>+</code> are added to the | |
| options currently in force, and any options preceded by a | |
| <code>-</code> are removed from the options currently in force.</p> | |
| <p> | |
| The available <em>option</em>s are:</p> | |
| <ul> | |
| <li><code>StdEnvVars</code> | |
| <p> | |
| When this option is enabled, the standard set of SSL related CGI/SSI | |
| environment variables are created. This per default is disabled for | |
| performance reasons, because the information extraction step is a | |
| rather expensive operation. So one usually enables this option for | |
| CGI and SSI requests only.</p> | |
| </li> | |
| <li><code>ExportCertData</code> | |
| <p> | |
| When this option is enabled, additional CGI/SSI environment variables are | |
| created: <code>SSL_SERVER_CERT</code>, <code>SSL_CLIENT_CERT</code> and | |
| <code>SSL_CLIENT_CERT_CHAIN_</code><em>n</em> (with <em>n</em> = 0,1,2,..). | |
| These contain the PEM-encoded X.509 Certificates of server and client for | |
| the current HTTPS connection and can be used by CGI scripts for deeper | |
| Certificate checking. Additionally all other certificates of the client | |
| certificate chain are provided, too. This bloats up the environment a | |
| little bit which is why you have to use this option to enable it on | |
| demand.</p> | |
| </li> | |
| <li><code>FakeBasicAuth</code> | |
| <p> | |
| When this option is enabled, the Subject Distinguished Name (DN) of the | |
| Client X509 Certificate is translated into a HTTP Basic Authorization | |
| username. This means that the standard Apache authentication methods can | |
| be used for access control. The user name is just the Subject of the | |
| Client's X509 Certificate (can be determined by running OpenSSL's | |
| <code>openssl x509</code> command: <code>openssl x509 -noout -subject -in | |
| </code><em>certificate</em><code>.crt</code>). Note that no password is | |
| obtained from the user. Every entry in the user file needs this password: | |
| ``<code>xxj31ZMTZzkVA</code>'', which is the DES-encrypted version of the | |
| word `<code>password</code>''. Those who live under MD5-based encryption | |
| (for instance under FreeBSD or BSD/OS, etc.) should use the following MD5 | |
| hash of the same word: ``<code>$1$OXLyS...$Owx8s2/m9/gfkcRVXzgoE/</code>''.</p> | |
| </li> | |
| <li><code>StrictRequire</code> | |
| <p> | |
| This <em>forces</em> forbidden access when <code>SSLRequireSSL</code> or | |
| <code>SSLRequire</code> successfully decided that access should be | |
| forbidden. Usually the default is that in the case where a ``<code>Satisfy | |
| any</code>'' directive is used, and other access restrictions are passed, | |
| denial of access due to <code>SSLRequireSSL</code> or | |
| <code>SSLRequire</code> is overridden (because that's how the Apache | |
| <code>Satisfy</code> mechanism should work.) But for strict access restriction | |
| you can use <code>SSLRequireSSL</code> and/or <code>SSLRequire</code> in | |
| combination with an ``<code>SSLOptions +StrictRequire</code>''. Then an | |
| additional ``<code>Satisfy Any</code>'' has no chance once mod_ssl has | |
| decided to deny access.</p> | |
| </li> | |
| <li><code>OptRenegotiate</code> | |
| <p> | |
| This enables optimized SSL connection renegotiation handling when SSL | |
| directives are used in per-directory context. By default a strict | |
| scheme is enabled where <em>every</em> per-directory reconfiguration of | |
| SSL parameters causes a <em>full</em> SSL renegotiation handshake. When this | |
| option is used mod_ssl tries to avoid unnecessary handshakes by doing more | |
| granular (but still safe) parameter checks. Nevertheless these granular | |
| checks sometimes maybe not what the user expects, so enable this on a | |
| per-directory basis only, please.</p> | |
| </li> | |
| </ul> | |
| <example><title>Example</title> | |
| SSLOptions +FakeBasicAuth -StrictRequire<br /> | |
| <Files ~ "\.(cgi|shtml)$"><br /> | |
| SSLOptions +StdEnvVars -ExportCertData<br /> | |
| <Files> | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLRequireSSL</name> | |
| <description>Deny access when SSL is not used for the | |
| HTTP request</description> | |
| <syntax>SSLRequireSSL</syntax> | |
| <contextlist><context>directory</context> | |
| <context>.htaccess</context></contextlist> | |
| <override>AuthConfig</override> | |
| <usage> | |
| <p><!-- XXX: I think the syntax is wrong --> | |
| This directive forbids access unless HTTP over SSL (i.e. HTTPS) is enabled for | |
| the current connection. This is very handy inside the SSL-enabled virtual | |
| host or directories for defending against configuration errors that expose | |
| stuff that should be protected. When this directive is present all requests | |
| are denied which are not using SSL.</p> | |
| <example><title>Example</title> | |
| SSLRequireSSL | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLRequire</name> | |
| <description>Allow access only when an arbitrarily complex | |
| boolean expression is true</description> | |
| <syntax>SSLRequire <em>expression</em></syntax> | |
| <contextlist><context>directory</context> | |
| <context>.htaccess</context></contextlist> | |
| <override>AuthConfig</override> | |
| <usage> | |
| <p> | |
| This directive specifies a general access requirement which has to be | |
| fulfilled in order to allow access. It is a very powerful directive because the | |
| requirement specification is an arbitrarily complex boolean expression | |
| containing any number of access checks.</p> | |
| <p> | |
| The <em>expression</em> must match the following syntax (given as a BNF | |
| grammar notation):</p> | |
| <blockquote> | |
| <pre> | |
| expr ::= "<strong>true</strong>" | "<strong>false</strong>" | |
| | "<strong>!</strong>" expr | |
| | expr "<strong>&&</strong>" expr | |
| | expr "<strong>||</strong>" expr | |
| | "<strong>(</strong>" expr "<strong>)</strong>" | |
| | comp | |
| comp ::= word "<strong>==</strong>" word | word "<strong>eq</strong>" word | |
| | word "<strong>!=</strong>" word | word "<strong>ne</strong>" word | |
| | word "<strong><</strong>" word | word "<strong>lt</strong>" word | |
| | word "<strong><=</strong>" word | word "<strong>le</strong>" word | |
| | word "<strong>></strong>" word | word "<strong>gt</strong>" word | |
| | word "<strong>>=</strong>" word | word "<strong>ge</strong>" word | |
| | word "<strong>in</strong>" "<strong>{</strong>" wordlist "<strong>}</strong>" | |
| | word "<strong>in</strong>" "<strong>PeerExtList(</strong>" word "<strong>)</strong>" | |
| | word "<strong>=~</strong>" regex | |
| | word "<strong>!~</strong>" regex | |
| wordlist ::= word | |
| | wordlist "<strong>,</strong>" word | |
| word ::= digit | |
| | cstring | |
| | variable | |
| | function | |
| digit ::= [0-9]+ | |
| cstring ::= "..." | |
| variable ::= "<strong>%{</strong>" varname "<strong>}</strong>" | |
| function ::= funcname "<strong>(</strong>" funcargs "<strong>)</strong>" | |
| </pre> | |
| </blockquote> | |
| <p>For <code>varname</code> any of the variables described in <a | |
| href="#envvars">Environment Variables</a> can be used. For | |
| <code>funcname</code> the following functions are available:</p> | |
| <ul> | |
| <li><code>file(</code><em>filename</em><code>)</code> | |
| <p> | |
| This function takes one string argument and expands to the contents of the | |
| file. This is especially useful for matching this contents against a | |
| regular expression, etc.</p> | |
| </li> | |
| </ul> | |
| <p>Notice that <em>expression</em> is first parsed into an internal machine | |
| representation and then evaluated in a second step. Actually, in Global and | |
| Per-Server Class context <em>expression</em> is parsed at startup time and | |
| at runtime only the machine representation is executed. For Per-Directory | |
| context this is different: here <em>expression</em> has to be parsed and | |
| immediately executed for every request.</p> | |
| <example><title>Example</title> | |
| <pre>SSLRequire ( %{SSL_CIPHER} !~ m/^(EXP|NULL)-/ \ | |
| and %{SSL_CLIENT_S_DN_O} eq "Snake Oil, Ltd." \ | |
| and %{SSL_CLIENT_S_DN_OU} in {"Staff", "CA", "Dev"} \ | |
| and %{TIME_WDAY} >= 1 and %{TIME_WDAY} <= 5 \ | |
| and %{TIME_HOUR} >= 8 and %{TIME_HOUR} <= 20 ) \ | |
| or %{REMOTE_ADDR} =~ m/^192\.76\.162\.[0-9]+$/</pre> | |
| </example> | |
| <p>The <code>PeerExtList(<em>object-ID</em>)</code> function expects | |
| to find zero or more instances of the X.509 certificate extension | |
| identified by the given <em>object ID</em> (OID) in the client certificate. | |
| The expression evaluates to true if the left-hand side string matches | |
| exactly against the value of an extension identified with this OID. | |
| (If multiple extensions with the same OID are present, at least one | |
| extension must match).</p> | |
| <example><title>Example</title> | |
| SSLRequire "foobar" in PeerExtList("1.2.3.4.5.6") | |
| </example> | |
| <note><title>Notes on the PeerExtList function</title> | |
| <ul> | |
| <li><p>The object ID can be specified either as a descriptive | |
| name recognized by the SSL library, such as <code>"nsComment"</code>, | |
| or as a numeric OID, such as <code>"1.2.3.4.5.6"</code>.</p></li> | |
| <li><p>Expressions with types known to the SSL library are rendered to | |
| a string before comparison. For an extension with a type not | |
| recognized by the SSL library, mod_ssl will parse the value if it is | |
| one of the primitive ASN.1 types UTF8String, IA5String, VisibleString, | |
| or BMPString. For an extension of one of these types, the string | |
| value will be converted to UTF-8 if necessary, then compared against | |
| the left-hand-side expression.</p></li> | |
| </ul> | |
| </note> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLRenegBufferSize</name> | |
| <description>Set the size for the SSL renegotiation buffer</description> | |
| <syntax>SSLRenegBufferSize <var>bytes</var></syntax> | |
| <default>SSLRenegBufferSize 131072</default> | |
| <contextlist><context>directory</context> | |
| <context>.htaccess</context></contextlist> | |
| <override>AuthConfig</override> | |
| <usage> | |
| <p>If an SSL renegotiation is required in per-location context, for | |
| example, any use of <directive | |
| module="mod_ssl">SSLVerifyClient</directive> in a Directory or | |
| Location block, then <module>mod_ssl</module> must buffer any HTTP | |
| request body into memory until the new SSL handshake can be performed. | |
| This directive can be used to set the amount of memory that will be | |
| used for this buffer. </p> | |
| <note type="warning"><p> | |
| Note that in many configurations, the client sending the request body | |
| will be untrusted so a denial of service attack by consumption of | |
| memory must be considered when changing this configuration setting. | |
| </p></note> | |
| <example><title>Example</title> | |
| SSLRenegBufferSize 262144 | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLStrictSNIVHostCheck</name> | |
| <description>Whether to allow non-SNI clients to access a name-based virtual | |
| host. | |
| </description> | |
| <syntax>SSLStrictSNIVHostCheck on|off</syntax> | |
| <default>SSLStrictSNIVHostCheck off</default> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <compatibility>Available in Apache 2.2.12 and later</compatibility> | |
| <usage> | |
| <p> | |
| This directive sets whether a non-SNI client is allowed to access a name-based | |
| virtual host. If set to <code>on</code> in the default name-based virtual | |
| host, clients that are SNI unaware will not be allowed to access <em>any</em> | |
| virtual host, belonging to this particular IP / port combination. | |
| If set to <code>on</code> in any other virtual host, SNI unaware clients | |
| are not allowed to access this particular virtual host. | |
| </p> | |
| <note type="warning"><p> | |
| This option is only available if httpd was compiled against an SNI capable | |
| version of OpenSSL. | |
| </p></note> | |
| <example><title>Example</title> | |
| SSLStrictSNIVHostCheck on | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLProxyMachineCertificatePath</name> | |
| <description>Directory of PEM-encoded client certificates and keys to be used by the proxy</description> | |
| <syntax>SSLProxyMachineCertificatePath <em>directory</em></syntax> | |
| <contextlist><context>server config</context></contextlist> | |
| <override>Not applicable</override> | |
| <usage> | |
| <p> | |
| This directive sets the directory where you keep the certificates and | |
| keys used for authentication of the proxy server to remote servers. | |
| </p> | |
| <p>The files in this directory must be PEM-encoded and are accessed through | |
| hash filenames. Additionally, you must create symbolic links named | |
| <code><em>hash-value</em>.N</code>. And you should always make sure this | |
| directory contains the appropriate symbolic links. Use the Makefile which | |
| comes with mod_ssl to accomplish this task. | |
| </p> | |
| <note type="warning"> | |
| <p>Currently there is no support for encrypted private keys</p> | |
| </note> | |
| <example><title>Example</title> | |
| SSLProxyMachineCertificatePath /usr/local/apache2/conf/proxy.crt/ | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLProxyMachineCertificateFile</name> | |
| <description>File of concatenated PEM-encoded client certificates and keys to be used by the proxy</description> | |
| <syntax>SSLProxyMachineCertificateFile <em>filename</em></syntax> | |
| <contextlist><context>server config</context></contextlist> | |
| <override>Not applicable</override> | |
| <usage> | |
| <p> | |
| This directive sets the all-in-one file where you keep the certificates and | |
| keys used for authentication of the proxy server to remote servers. | |
| </p> | |
| <p> | |
| This referenced file is simply the concatenation of the various PEM-encoded | |
| certificate files, in order of preference. Use this directive alternatively | |
| or additionally to <code>SSLProxyMachineCertificatePath</code>. | |
| </p> | |
| <note type="warning"> | |
| <p>Currently there is no support for encrypted private keys</p> | |
| </note> | |
| <example><title>Example</title> | |
| SSLProxyMachineCertificateFile /usr/local/apache2/conf/ssl.crt/proxy.pem | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLProxyVerify</name> | |
| <description>Type of remote server Certificate verification</description> | |
| <syntax>SSLProxyVerify <em>level</em></syntax> | |
| <default>SSLProxyVerify none</default> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context> | |
| <context>directory</context> | |
| <context>.htaccess</context></contextlist> | |
| <override>AuthConfig</override> | |
| <usage> | |
| <p>When a proxy is configured to forward requests to a remote SSL | |
| server, this directive can be used to configure certificate | |
| verification of the remote server. Notice that this directive can be | |
| used both in per-server and per-directory context. In per-server | |
| context it applies to the remote server authentication process used in | |
| the standard SSL handshake when a connection is established by the | |
| proxy. In per-directory context it forces a SSL renegotiation with the | |
| reconfigured remote server verification level after the HTTP request | |
| was read but before the HTTP response is sent.</p> | |
| <p> | |
| The following levels are available for <em>level</em>:</p> | |
| <ul> | |
| <li><strong>none</strong>: | |
| no remote server Certificate is required at all</li> | |
| <li><strong>optional</strong>: | |
| the remote server <em>may</em> present a valid Certificate</li> | |
| <li><strong>require</strong>: | |
| the remote server <em>has to</em> present a valid Certificate</li> | |
| <li><strong>optional_no_ca</strong>: | |
| the remote server may present a valid Certificate<br /> | |
| but it need not to be (successfully) verifiable.</li> | |
| </ul> | |
| <p>In practice only levels <strong>none</strong> and | |
| <strong>require</strong> are really interesting, because level | |
| <strong>optional</strong> doesn't work with all servers and level | |
| <strong>optional_no_ca</strong> is actually against the idea of | |
| authentication (but can be used to establish SSL test pages, etc.)</p> | |
| <example><title>Example</title> | |
| SSLProxyVerify require | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLProxyVerifyDepth</name> | |
| <description>Maximum depth of CA Certificates in Remote Server | |
| Certificate verification</description> | |
| <syntax>SSLProxyVerifyDepth <em>number</em></syntax> | |
| <default>SSLProxyVerifyDepth 1</default> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context> | |
| <context>directory</context> | |
| <context>.htaccess</context></contextlist> | |
| <override>AuthConfig</override> | |
| <usage> | |
| <p> | |
| This directive sets how deeply mod_ssl should verify before deciding that the | |
| remote server does not have a valid certificate. Notice that this directive can be | |
| used both in per-server and per-directory context. In per-server context it | |
| applies to the client authentication process used in the standard SSL | |
| handshake when a connection is established. In per-directory context it forces | |
| a SSL renegotiation with the reconfigured remote server verification depth after the | |
| HTTP request was read but before the HTTP response is sent.</p> | |
| <p> | |
| The depth actually is the maximum number of intermediate certificate issuers, | |
| i.e. the number of CA certificates which are max allowed to be followed while | |
| verifying the remote server certificate. A depth of 0 means that self-signed | |
| remote server certificates are accepted only, the default depth of 1 means | |
| the remote server certificate can be self-signed or has to be signed by a CA | |
| which is directly known to the server (i.e. the CA's certificate is under | |
| <directive module="mod_ssl">SSLProxyCACertificatePath</directive>), etc.</p> | |
| <example><title>Example</title> | |
| SSLProxyVerifyDepth 10 | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLProxyCheckPeerExpire</name> | |
| <description>Whether to check if remote server certificate is expired | |
| </description> | |
| <syntax>SSLProxyCheckPeerExpire on|off</syntax> | |
| <default>SSLProxyCheckPeerExpire on</default> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive sets whether it is checked if the remote server certificate | |
| is expired or not. If the check fails a 502 status code (Bad Gateway) is | |
| sent. | |
| </p> | |
| <example><title>Example</title> | |
| SSLProxyCheckPeerExpire on | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLProxyCheckPeerCN</name> | |
| <description>Whether to check the remote server certificates CN field | |
| </description> | |
| <syntax>SSLProxyCheckPeerCN on|off</syntax> | |
| <default>SSLProxyCheckPeerCN on</default> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive sets whether the remote server certificates CN field is | |
| compared against the hostname of the request URL. If both are not equal | |
| a 502 status code (Bad Gateway) is sent. | |
| </p> | |
| <example><title>Example</title> | |
| SSLProxyCheckPeerCN on | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLProxyEngine</name> | |
| <description>SSL Proxy Engine Operation Switch</description> | |
| <syntax>SSLProxyEngine on|off</syntax> | |
| <default>SSLProxyEngine off</default> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive toggles the usage of the SSL/TLS Protocol Engine for proxy. This | |
| is usually used inside a <directive module="core" | |
| type="section">VirtualHost</directive> section to enable SSL/TLS for proxy | |
| usage in a particular virtual host. By default the SSL/TLS Protocol Engine is | |
| disabled for proxy image both for the main server and all configured virtual hosts.</p> | |
| <example><title>Example</title> | |
| <VirtualHost _default_:443><br /> | |
| SSLProxyEngine on<br /> | |
| ...<br /> | |
| </VirtualHost> | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLProxyProtocol</name> | |
| <description>Configure usable SSL protocol flavors for proxy usage</description> | |
| <syntax>SSLProxyProtocol [+|-]<em>protocol</em> ...</syntax> | |
| <default>SSLProxyProtocol all</default> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <override>Options</override> | |
| <usage> | |
| <!-- XXX Why does this have an override and not .htaccess context? --> | |
| <p> | |
| This directive can be used to control the SSL protocol flavors mod_ssl should | |
| use when establishing its server environment for proxy . It will only connect | |
| to servers using one of the provided protocols.</p> | |
| <p>Please refer to <directive module="mod_ssl">SSLProtocol</directive> | |
| for additional information. | |
| </p> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLProxyCipherSuite</name> | |
| <description>Cipher Suite available for negotiation in SSL | |
| proxy handshake</description> | |
| <syntax>SSLProxyCipherSuite <em>cipher-spec</em></syntax> | |
| <default>SSLProxyCipherSuite ALL:!ADH:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv2:+EXP</default> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context> | |
| <context>directory</context> | |
| <context>.htaccess</context></contextlist> | |
| <override>AuthConfig</override> | |
| <usage> | |
| <p>Equivalent to <code>SSLCipherSuite</code>, but for the proxy connection. | |
| Please refer to <directive module="mod_ssl">SSLCipherSuite</directive> | |
| for additional information.</p> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLProxyCACertificatePath</name> | |
| <description>Directory of PEM-encoded CA Certificates for | |
| Remote Server Auth</description> | |
| <syntax>SSLProxyCACertificatePath <em>directory-path</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive sets the directory where you keep the Certificates of | |
| Certification Authorities (CAs) whose remote servers you deal with. These are used to | |
| verify the remote server certificate on Remote Server Authentication.</p> | |
| <p> | |
| The files in this directory have to be PEM-encoded and are accessed through | |
| hash filenames. So usually you can't just place the Certificate files | |
| there: you also have to create symbolic links named | |
| <em>hash-value</em><code>.N</code>. And you should always make sure this directory | |
| contains the appropriate symbolic links. Use the <code>Makefile</code> which | |
| comes with mod_ssl to accomplish this task.</p> | |
| <example><title>Example</title> | |
| SSLProxyCACertificatePath /usr/local/apache2/conf/ssl.crt/ | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLProxyCACertificateFile</name> | |
| <description>File of concatenated PEM-encoded CA Certificates | |
| for Remote Server Auth</description> | |
| <syntax>SSLProxyCACertificateFile <em>file-path</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive sets the <em>all-in-one</em> file where you can assemble the | |
| Certificates of Certification Authorities (CA) whose <em>remote servers</em> you deal | |
| with. These are used for Remote Server Authentication. Such a file is simply the | |
| concatenation of the various PEM-encoded Certificate files, in order of | |
| preference. This can be used alternatively and/or additionally to | |
| <directive module="mod_ssl">SSLProxyCACertificatePath</directive>.</p> | |
| <example><title>Example</title> | |
| SSLProxyCACertificateFile /usr/local/apache2/conf/ssl.crt/ca-bundle-remote-server.crt | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLProxyCARevocationPath</name> | |
| <description>Directory of PEM-encoded CA CRLs for | |
| Remote Server Auth</description> | |
| <syntax>SSLProxyCARevocationPath <em>directory-path</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive sets the directory where you keep the Certificate Revocation | |
| Lists (CRL) of Certification Authorities (CAs) whose remote servers you deal with. | |
| These are used to revoke the remote server certificate on Remote Server Authentication.</p> | |
| <p> | |
| The files in this directory have to be PEM-encoded and are accessed through | |
| hash filenames. So usually you have not only to place the CRL files there. | |
| Additionally you have to create symbolic links named | |
| <em>hash-value</em><code>.rN</code>. And you should always make sure this directory | |
| contains the appropriate symbolic links. Use the <code>Makefile</code> which | |
| comes with <module>mod_ssl</module> to accomplish this task.</p> | |
| <example><title>Example</title> | |
| SSLProxyCARevocationPath /usr/local/apache2/conf/ssl.crl/ | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLProxyCARevocationFile</name> | |
| <description>File of concatenated PEM-encoded CA CRLs for | |
| Remote Server Auth</description> | |
| <syntax>SSLProxyCARevocationFile <em>file-path</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive sets the <em>all-in-one</em> file where you can | |
| assemble the Certificate Revocation Lists (CRL) of Certification | |
| Authorities (CA) whose <em>remote servers</em> you deal with. These are used | |
| for Remote Server Authentication. Such a file is simply the concatenation of | |
| the various PEM-encoded CRL files, in order of preference. This can be | |
| used alternatively and/or additionally to <directive | |
| module="mod_ssl">SSLProxyCARevocationPath</directive>.</p> | |
| <example><title>Example</title> | |
| SSLProxyCARevocationFile /usr/local/apache2/conf/ssl.crl/ca-bundle-remote-server.crl | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLUserName</name> | |
| <description>Variable name to determine user name</description> | |
| <syntax>SSLUserName <em>varname</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>directory</context> | |
| <context>.htaccess</context></contextlist> | |
| <override>AuthConfig</override> | |
| <compatibility>Available in Apache 2.0.51 and later</compatibility> | |
| <usage> | |
| <p> | |
| This directive sets the "user" field in the Apache request object. | |
| This is used by lower modules to identify the user with a character | |
| string. In particular, this may cause the environment variable | |
| <code>REMOTE_USER</code> to be set. The <em>varname</em> can be | |
| any of the <a href="#envvars">SSL environment variables</a>.</p> | |
| <p>Note that this directive has no effect if the | |
| <code>FakeBasicAuth</code> option is used (see <a | |
| href="#ssloptions">SSLOptions</a>).</p> | |
| <example><title>Example</title> | |
| SSLUserName SSL_CLIENT_S_DN_CN | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLHonorCipherOrder</name> | |
| <description>Option to prefer the server's cipher preference order</description> | |
| <syntax>SSLHonorCipherOrder <em>flag</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <compatibility>Available in Apache 2.1 and later, if using OpenSSL 0.9.7 or later</compatibility> | |
| <usage> | |
| <p>When choosing a cipher during an SSLv3 or TLSv1 handshake, normally | |
| the client's preference is used. If this directive is enabled, the | |
| server's preference will be used instead.</p> | |
| <example><title>Example</title> | |
| SSLHonorCipherOrder on | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLCryptoDevice</name> | |
| <description>Enable use of a cryptographic hardware accelerator</description> | |
| <syntax>SSLCryptoDevice <em>engine</em></syntax> | |
| <default>SSLCryptoDevice builtin</default> | |
| <contextlist><context>server config</context></contextlist> | |
| <usage> | |
| <p> | |
| This directive enables use of a cryptographic hardware accelerator | |
| board to offload some of the SSL processing overhead. This directive | |
| can only be used if the SSL toolkit is built with "engine" support; | |
| OpenSSL 0.9.7 and later releases have "engine" support by default, the | |
| separate "-engine" releases of OpenSSL 0.9.6 must be used.</p> | |
| <p>To discover which engine names are supported, run the command | |
| "<code>openssl engine</code>".</p> | |
| <example><title>Example</title> | |
| # For a Broadcom accelerator:<br /> | |
| SSLCryptoDevice ubsec | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLOCSPEnable</name> | |
| <description>Enable OCSP validation of the client certificate chain</description> | |
| <syntax>SSLOCSPEnable <em>flag</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <compatibility>Available in httpd 2.3 and later, if using OpenSSL 0.9.7 or later</compatibility> | |
| <usage> | |
| <p>This option enables OCSP validation of the client certificate | |
| chain. If this option is enabled, certificates in the client's | |
| certificate chain will be validated against an OCSP responder after | |
| normal verification (including CRL checks) have taken place.</p> | |
| <p>The OCSP responder used is either extracted from the certificate | |
| itself, or derived by configuration; see the | |
| <directive module="mod_ssl">SSLOCSPDefaultResponder</directive> and | |
| <directive module="mod_ssl">SSLOCSPOverrideResponder</directive> | |
| directives.</p> | |
| <example><title>Example</title> | |
| SSLVerifyClient on<br/> | |
| SSLOCSPEnable on<br/> | |
| SSLOCSPDefaultResponder http://responder.example.com:8888/responder<br/> | |
| SSLOCSPOverrideResponder on | |
| </example> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLOCSPDefaultResponder</name> | |
| <description>Set the default responder URI for OCSP validation</description> | |
| <syntax>SSLOCSDefaultResponder <em>uri</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <compatibility>Available in httpd 2.3 and later, if using OpenSSL 0.9.7 or later</compatibility> | |
| <usage> | |
| <p>This option sets the default OCSP responder to use. If <directive | |
| module="mod_ssl">SSLOCSPOverrideResponder</directive> is not enabled, | |
| the URI given will be used only if no responder URI is specified in | |
| the certificate being verified.</p> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLOCSPOverrideResponder</name> | |
| <description>Force use of the default responder URI for OCSP validation</description> | |
| <syntax>SSLOCSPOverrideResponder <em>flag</em></syntax> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <compatibility>Available in httpd 2.3 and later, if using OpenSSL 0.9.7 or later</compatibility> | |
| <usage> | |
| <p>This option forces the configured default OCSP responder to be used | |
| during OCSP certificate validation, regardless of whether the | |
| certificate being validated references an OCSP responder.</p> | |
| </usage> | |
| </directivesynopsis> | |
| <directivesynopsis> | |
| <name>SSLInsecureRenegotiation</name> | |
| <description>Option to enable support for insecure renegotiation</description> | |
| <syntax>SSLInsecureRenegotiation <em>flag</em></syntax> | |
| <default>SSLInsecureRenegotiation off</default> | |
| <contextlist><context>server config</context> | |
| <context>virtual host</context></contextlist> | |
| <compatibility>Available in httpd 2.2.15 and later, if using OpenSSL 0.9.8m or later</compatibility> | |
| <usage> | |
| <p>As originally specified, all versions of the SSL and TLS protocols | |
| (up to and including TLS/1.2) were vulnerable to a Man-in-the-Middle | |
| attack | |
| (<a href="http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2009-3555">CVE-2009-3555</a>) | |
| during a renegotiation. This vulnerability allowed an attacker to | |
| "prefix" a chosen plaintext to the HTTP request as seen by the web | |
| server. A protocol extension was developed which fixed this | |
| vulnerability if supported by both client and server.</p> | |
| <p>If <module>mod_ssl</module> is linked against OpenSSL version 0.9.8m | |
| or later, by default renegotiation is only supported with | |
| clients supporting the new protocol extension. If this directive is | |
| enabled, renegotiation will be allowed with old (unpatched) clients, | |
| albeit insecurely.</p> | |
| <note type="warning"><title>Security warning</title> | |
| <p>If this directive is enabled, SSL connections will be vulnerable to | |
| the Man-in-the-Middle prefix attack as described | |
| in <a href="http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2009-3555">CVE-2009-3555</a>.</p> | |
| </note> | |
| <example><title>Example</title> | |
| SSLInsecureRenegotiation on | |
| </example> | |
| <p>The <code>SSL_SECURE_RENEG</code> environment variable can be used | |
| from an SSI or CGI script to determine whether secure renegotiation is | |
| supported for a given SSL connection.</p> | |
| </usage> | |
| </directivesynopsis> | |
| </modulesynopsis> |