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1581 lines
63 KiB
Plaintext
1581 lines
63 KiB
Plaintext
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#use "ssl_template.inc" title="Reference" tag=ref num=3
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<page_prev name="Introduction" url="ssl_intro.html">
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<page_next name="Compatibility" url="ssl_compat.html">
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#use wml::std::toc style=nbsp
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#use wml::std::grid
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<quotation width=150 author="Unknown">
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``Try to understand everything,
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but believe nothing!''
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</quotation>
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<p>
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<table cellspacing="0" cellpadding="0" border="0">
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<tr valign="bottom">
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<td>
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<big T>his chapter provides a reference to all configuration directives and
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additional user visible features mod_ssl provides. It's intended as the
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official resource when you want to know how a particilar mod_ssl functionality
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is actually configured or activated. Each directive is documented similar to
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the way standard Apache directives are documented in the official Apache
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documentation set, i.e. for each directive especially the syntax, default and
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context where applicable is given.
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<p>
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Notice that there are three major classes of directives which are used by
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mod_ssl: First <em>Global Directives</em> (i.e. directives with context
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``server config''), which can occur inside the server config files but only
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outside of any sectioning commands like <VirtualHost>. Second
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<em>Per-Server Directives</em> (i.e. those with context ``server config,
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virtual host''), which can occur inside the server config files both outside
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(for the main/default server) and inside <VirtualHost> sections.
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</td>
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<td>
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</td>
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<td>
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<div align="right">
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<table cellspacing="0" cellpadding="5" border="0" bgcolor="#ccccff">
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<tr>
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<td bgcolor="#333399">
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<font face="Arial,Helvetica" color="#ccccff">
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<b>Table Of Contents</b>
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</font>
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</td>
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</tr>
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<tr>
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<td>
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<font face="Arial,Helvetica" size="-1">
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<toc>
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</font>
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</td>
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</tr>
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</table>
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</div>
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</td>
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</tr>
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</table>
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<p>
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And third <em>Per-Directory Directives</em> (i.e. those with context ``server
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config, virtual host, directory, .htaccess''), which can pretty much occur
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everywhere. Especially both inside the server config files and the
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per-directory <code>.htaccess</code> files. The three classes are subsets of
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each other, i.e. directives from the per-directory class can also be used in
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the per-server and global context, and directives from the per-server class
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can also be used the in the global context.
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<p>
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Additional directives and environment variables provided by mod_ssl (via
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on-the-fly mapping) for backward compatiblity to other Apache SSL solutions
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are documented in the <a href="ssl_compat.html">Compatibility</a> chapter.
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<h1>Configuration Directives</h1>
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The most visible and error-prone things of mod_ssl are its configuration
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directives. So we document them in great detail here to assist you in setting
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up the best possible configuration of your SSL-aware webserver.
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<!-- SSLPassPhraseDialog -------------------------------------------->
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<p>
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<br>
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<a name="SSLPassPhraseDialog"></a>
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<h2>SSLPassPhraseDialog</h2>
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<p>
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<directive
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name="SSLPassPhraseDialog"
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description="Type of pass phrase dialog for encrypted private keys"
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syntax="<code>SSLPassPhraseDialog</code> <em>type</em>"
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default="<code>SSLPassPhraseDialog builtin</code>"
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context="server config"
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override="<em>Not applicable</em>"
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compat="mod_ssl 2.1"
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>
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<p>
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When Apache starts up it has to read the various Certificate (see <a
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href="#SSLCertificateFile">SSLCertificateFile</a>) and Private Key (see <a
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href="#SSLCertificateKeyFile">SSLCertificateKeyFile</a>) files of the
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SSL-enabled virtual servers. Because for security reasons the Private Key
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files are usually encrypted, mod_ssl needs to query the administrator for a
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Pass Phrase in order to decrypt those files. This query can be done in two ways
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which can be configured by <em>type</em>:
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<ul>
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<li><code>builtin</code>
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<p>
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This is the default where an interactive terminal dialog occurs at startup
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time just before Apache detaches from the terminal. Here the administrator
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has to manually enter the Pass Phrase for each encrypted Private Key file.
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Because a lot of SSL-enabled virtual hosts can be configured, the
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following reuse-scheme is used to minimize the dialog: When a Private Key
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file is encrypted, all known Pass Phrases (at the beginning there are
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none, of course) are tried. If one of those known Pass Phrases succeeds no
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dialog pops up for this particular Private Key file. If none succeeded,
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another Pass Phrase is queried on the terminal and remembered for the next
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round (where it perhaps can be reused).
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<p>
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This scheme allows mod_ssl to be maximally flexible (because for N encrypted
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Private Key files you <em>can</em> use N different Pass Phrases - but then
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you have to enter all of them, of course) while minimizing the terminal
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dialog (i.e. when you use a single Pass Phrase for all N Private Key files
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this Pass Phrase is queried only once).
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<p>
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<li><code>exec:/path/to/program</code>
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<p>
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Here an external program is configured which is called at startup for each
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encrypted Private Key file. It is called with two arguments (the first is
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of the form ``<code>servername:portnumber</code>'', the second is either
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``<code>RSA</code>'' or ``<code>DSA</code>''), which indicate for which
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server and algorithm it has to print the corresponding Pass Phrase to
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<code>stdout</code>. The intent is that this external program first runs
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security checks to make sure that the system is not compromised by an
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attacker, and only when these checks were passed successfully it provides
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the Pass Phrase.
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<p>
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Both these security checks, and the way the Pass Phrase is determined, can
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be as complex as you like. Mod_ssl just defines the interface: an
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executable program which provides the Pass Phrase on <code>stdout</code>.
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Nothing more or less! So, if you're really paranoid about security, here
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is your interface. Anything else has to be left as an exercise to the
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administrator, because local security requirements are so different.
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<p>
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The reuse-algorithm above is used here, too. In other words: The external
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program is called only once per unique Pass Phrase.
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</ul>
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<p>
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Example:
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<blockquote>
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<pre>
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SSLPassPhraseDialog exec:/usr/local/apache/sbin/pp-filter
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</pre>
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</blockquote>
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<!-- SSLMutex ------------------------------------------------------->
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<p>
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<br>
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<a name="SSLMutex"></a>
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<h2>SSLMutex</h2>
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<p>
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<directive
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name="SSLMutex"
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description="Semaphore for internal mutual exclusion of operations"
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syntax="<code>SSLMutex</code> <em>type</em>"
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default="<code>SSLMutex none</code>"
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context="server config"
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override="<em>Not applicable</em>"
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compat="mod_ssl 2.1"
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>
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<p>
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This configures the SSL engine's semaphore (aka. lock) which is used for mutual
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exclusion of operations which have to be done in a synchronized way between the
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pre-forked Apache server processes. This directive can only be used in the
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global server context because it's only useful to have one global mutex.
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<p>
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The following Mutex <em>types</em> are available:
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<ul>
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<li><code>none</code>
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<p>
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This is the default where no Mutex is used at all. Use it at your own
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risk. But because currently the Mutex is mainly used for synchronizing
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write access to the SSL Session Cache you can live without it as long
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as you accept a sometimes garbled Session Cache. So it's not recommended
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to leave this the default. Instead configure a real Mutex.
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<p>
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<li><code>file:/path/to/mutex</code>
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<p>
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This is the portable and (under Unix) always provided Mutex variant where
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a physical (lock-)file is used as the Mutex. Always use a local disk
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filesystem for <code>/path/to/mutex</code> and never a file residing on a
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NFS- or AFS-filesystem. Note: Internally, the Process ID (PID) of the
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Apache parent process is automatically appended to
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<code>/path/to/mutex</code> to make it unique, so you don't have to worry
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about conflicts yourself. Notice that this type of mutex is not available
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under the Win32 environment. There you <i>have</i> to use the semaphore
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mutex.
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<p>
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<li><code>sem</code>
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<p>
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This is the most elegant but also most non-portable Mutex variant where a
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SysV IPC Semaphore (under Unix) and a Windows Mutex (under Win32) is used
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when possible. It is only available when the underlying platform
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supports it.
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</ul>
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<p>
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Example:
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<blockquote>
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<pre>
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SSLMutex file:/usr/local/apache/logs/ssl_mutex
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</pre>
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</blockquote>
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<!-- SSLRandomSeed -------------------------------------------------->
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<p>
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<br>
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<a name="SSLRandomSeed"></a>
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<h2>SSLRandomSeed</h2>
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<p>
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<directive
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name="SSLRandomSeed"
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description="Pseudo Random Number Generator (PRNG) seeding source"
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syntax="<code>SSLRandomSeed</code> <em>context</em> <em>source</em> [<em>bytes</em>]"
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default="<em>none</em>"
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context="server config"
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override="<em>Not applicable</em>"
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compat="mod_ssl 2.2"
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>
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<p>
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This configures one or more sources for seeding the Pseudo Random Number
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Generator (PRNG) in OpenSSL at startup time (<em>context</em> is
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<code>startup</code>) and/or just before a new SSL connection is established
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(<em>context</em> is <code>connect</code>). This directive can only be used
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in the global server context because the PRNG is a global facility.
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<p>
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The following <em>source</em> variants are available:
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<ul>
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<li><code>builtin</code>
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<p> This is the always available builtin seeding source. It's usage
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consumes minimum CPU cycles under runtime and hence can be always used
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without drawbacks. The source used for seeding the PRNG contains of the
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current time, the current process id and (when applicable) a randomly
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choosen 1KB extract of the inter-process scoreboard structure of Apache.
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The drawback is that this is not really a strong source and at startup
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time (where the scoreboard is still not available) this source just
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produces a few bytes of entropy. So you should always, at least for the
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startup, use an additional seeding source.
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<p>
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<li><code>file:/path/to/source</code>
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<p>
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This variant uses an external file <code>/path/to/source</code> as the
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source for seeding the PRNG. When <em>bytes</em> is specified, only the
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first <em>bytes</em> number of bytes of the file form the entropy (and
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<em>bytes</em> is given to <code>/path/to/source</code> as the first
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argument). When <em>bytes</em> is not specified the whole file forms the
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entropy (and <code>0</code> is given to <code>/path/to/source</code> as
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the first argument). Use this especially at startup time, for instance
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with an available <code>/dev/random</code> and/or
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<code>/dev/urandom</code> devices (which usually exist on modern Unix
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derivates like FreeBSD and Linux).
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<p>
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<em>But be careful</em>: Usually <code>/dev/random</code> provides only as
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much entropy data as it actually has, i.e. when you request 512 bytes of
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entropy, but the device currently has only 100 bytes available two things
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can happen: On some platforms you receive only the 100 bytes while on
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other platforms the read blocks until enough bytes are available (which
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can take a long time). Here using an existing <code>/dev/urandom</code> is
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better, because it never blocks and actually gives the amount of requested
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data. The drawback is just that the quality of the received data may not
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be the best.
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<p>
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On some platforms like FreeBSD one can even control how the entropy is
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actually generated, i.e. by which system interrupts. More details one can
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find under <i>rndcontrol(8)</i> on those platforms. Alternatively, when
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your system lacks such a random device, you can use tool
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like <a href="http://www.lothar.com/tech/crypto/">EGD</a>
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(Entropy Gathering Daemon) and run it's client program with the
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<code>exec:/path/to/program/</code> variant (see below) or use
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<code>egd:/path/to/egd-socket</code> (see below).
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<p>
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<li><code>exec:/path/to/program</code>
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<p>
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This variant uses an external executable <code>/path/to/program</code> as
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the source for seeding the PRNG. When <em>bytes</em> is specified, only the
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first <em>bytes</em> number of bytes of its <code>stdout</code> contents
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form the entropy. When <em>bytes</em> is not specified, the entirety of
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the data produced on <code>stdout</code> form the entropy. Use this only
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at startup time when you need a very strong seeding with the help of an
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external program (for instance as in the example above with the
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<code>truerand</code> utility you can find in the mod_ssl distribution
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which is based on the AT&T <em>truerand</em> library). Using this in
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the connection context slows down the server too dramatically, of course.
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So usually you should avoid using external programs in that context.
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<p>
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<li><code>egd:/path/to/egd-socket</code> (Unix only)
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<p>
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This variant uses the Unix domain socket of the
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external Entropy Gathering Daemon (EGD) (see <a
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href="http://www.lothar.com/tech/crypto/">http://www.lothar.com/tech
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/crypto/</a>) to seed the PRNG. Use this if no random device exists
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on your platform.
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</ul>
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<p>
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Example:
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<blockquote>
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<pre>
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SSLRandomSeed startup builtin
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SSLRandomSeed startup file:/dev/random
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SSLRandomSeed startup file:/dev/urandom 1024
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SSLRandomSeed startup exec:/usr/local/bin/truerand 16
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SSLRandomSeed connect builtin
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SSLRandomSeed connect file:/dev/random
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SSLRandomSeed connect file:/dev/urandom 1024
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</pre>
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</blockquote>
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<!-- SSLSessionCache ------------------------------------------------>
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<p>
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<br>
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<a name="SSLSessionCache"></a>
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<h2>SSLSessionCache</h2>
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<directive
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name="SSLSessionCache"
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description="Type of the global/inter-process SSL Session Cache"
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syntax="<code>SSLSessionCache</code> <em>type</em>"
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default="<code>SSLSessionCache none</code>"
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context="server config"
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override="<em>Not applicable</em>"
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compat="mod_ssl 2.1"
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>
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<p>
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This configures the storage type of the global/inter-process SSL Session
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Cache. This cache is an optional facility which speeds up parallel request
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processing. For requests to the same server process (via HTTP keep-alive),
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OpenSSL already caches the SSL session information locally. But because modern
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clients request inlined images and other data via parallel requests (usually
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up to four parallel requests are common) those requests are served by
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<em>different</em> pre-forked server processes. Here an inter-process cache
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helps to avoid unneccessary session handshakes.
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<p>
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The following two storage <em>type</em>s are currently supported:
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<ul>
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<li><code>none</code>
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<p>
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This is the default and just disables the global/inter-process Session
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Cache. There is no drawback in functionality, but a noticeable speed
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penalty can be observed.
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<p>
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<li><code>dbm:/path/to/datafile</code>
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<p>
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This makes use of a DBM hashfile on the local disk to synchronize the
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local OpenSSL memory caches of the server processes. The slight increase
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in I/O on the server results in a visible request speedup for your
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clients, so this type of storage is generally recommended.
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<p>
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<li><code>shm:/path/to/datafile</code>[<code>(</code><i>size</i><code>)</code>]
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<p>
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This makes use of a high-performance hash table (approx. <i>size</i> bytes
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in size) inside a shared memory segment in RAM (established via
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<code>/path/to/datafile</code>) to synchronize the local OpenSSL memory
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caches of the server processes. This storage type is not available on all
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platforms. See the mod_ssl <code>INSTALL</code> document for details on
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how to build Apache+EAPI with shared memory support.
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</ul>
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<p>
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Examples:
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<blockquote>
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<pre>
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SSLSessionCache dbm:/usr/local/apache/logs/ssl_gcache_data
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SSLSessionCache shm:/usr/local/apache/logs/ssl_gcache_data(512000)
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</pre>
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</blockquote>
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<!-- SSLSessionCacheTimeout ----------------------------------------->
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<p>
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<br>
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<a name="SSLSessionCacheTimeout"></a>
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<h2>SSLSessionCacheTimeout</h2>
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<directive
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name="SSLSessionCacheTimeout"
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description="Number of seconds before an SSL session expires in the Session Cache"
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syntax="<code>SSLSessionCacheTimeout</code> <em>seconds</em>"
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default="<code>SSLSessionCacheTimeout 300</code>"
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context="server config, virtual host"
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override="<em>Not applicable</em>"
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compat="mod_ssl 2.0"
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>
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<p>
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This directive sets the timeout in seconds for the information stored in the
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global/inter-process SSL Session Cache and the OpenSSL internal memory cache.
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It can be set as low as 15 for testing, but should be set to higher
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values like 300 in real life.
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<p>
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|
Example:
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|
<blockquote>
|
|
<pre>
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SSLSessionCacheTimeout 600
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</pre>
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</blockquote>
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<!-- SSLEngine ------------------------------------------------------>
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<p>
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<br>
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<a name="SSLEngine"></a>
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<h2>SSLEngine</h2>
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|
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<directive
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name="SSLEngine"
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description="SSL Engine Operation Switch"
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syntax="<code>SSLEngine</code> <em>on|off</em>"
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default="<code>SSLEngine off</code>"
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context="server config, virtual host"
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override="<em>Not applicable</em>"
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compat="mod_ssl 2.1"
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>
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<p>
|
|
This directive toggles the usage of the SSL/TLS Protocol Engine. This is
|
|
usually used inside a <VirtualHost> section to enable SSL/TLS for a
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particular virtual host. By default the SSL/TLS Protocol Engine is disabled
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for both the main server and all configured virtual hosts.
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|
|
|
<p>
|
|
Example:
|
|
<blockquote>
|
|
<pre>
|
|
<VirtualHost _default_:443>
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SSLEngine on
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...
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</VirtualHost>
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</pre>
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|
</blockquote>
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<!-- SSLProtocol ---------------------------------------------------->
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|
<p>
|
|
<br>
|
|
<a name="SSLProtocol"></a>
|
|
<h2>SSLProtocol</h2>
|
|
|
|
<directive
|
|
name="SSLProtocol"
|
|
description="Configure usable SSL protocol flavors"
|
|
syntax="<code>SSLProtocol</code> [+-]<em>protocol</em> ..."
|
|
default="<code>SSLProtocol all</code>"
|
|
context="server config, virtual host"
|
|
override="Options"
|
|
compat="mod_ssl 2.2"
|
|
>
|
|
|
|
<p>
|
|
This directive can be used to control the SSL protocol flavors mod_ssl should
|
|
use when establishing its server environment. Clients then can only connect
|
|
with one of the provided protocols.
|
|
|
|
<p>
|
|
The available (case-insensitive) <em>protocol</em>s are:
|
|
|
|
<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.
|
|
<p>
|
|
<li><code>SSLv3</code>
|
|
<p>
|
|
This is the Secure Sockets Layer (SSL) protocol, version 3.0. It is the
|
|
successor to SSLv2 and the currently (as of February 1999) de-facto
|
|
standardized SSL protocol from Netscape Corporation. It's supported by
|
|
almost all popular browsers.
|
|
<p>
|
|
<li><code>TLSv1</code>
|
|
<p>
|
|
This is the Transport Layer Security (TLS) protocol, version 1.0. It is the
|
|
successor to SSLv3 and currently (as of February 1999) still under
|
|
construction by the Internet Engineering Task Force (IETF). It's still
|
|
not supported by any popular browsers.
|
|
<p>
|
|
<li><code>All</code>
|
|
<p>
|
|
This is a shortcut for ``<code>+SSLv2 +SSLv3 +TLSv1</code>'' and a
|
|
convinient way for enabling all protocols except one when used in
|
|
combination with the minus sign on a protocol as the example above shows.
|
|
</ul>
|
|
|
|
<p>
|
|
Example:
|
|
<blockquote>
|
|
<pre>
|
|
\# enable SSLv3 and TLSv1, but not SSLv2
|
|
SSLProtocol all -SSLv2
|
|
</pre>
|
|
</blockquote>
|
|
|
|
|
|
<!-- SSLCipherSuite ------------------------------------------------->
|
|
|
|
<p>
|
|
<br>
|
|
<a name="SSLCipherSuite"></a>
|
|
<h2>SSLCipherSuite</h2>
|
|
|
|
<directive
|
|
name="SSLCipherSuite"
|
|
description="Cipher Suite available for negotiation in SSL handshake"
|
|
syntax="<code>SSLCipherSuite</code> <em>cipher-spec</em>"
|
|
default="<code>SSLCipherSuite ALL:!ADH:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv2:+EXP</code>"
|
|
context="server config, virtual host, directory, .htaccess"
|
|
override="AuthConfig"
|
|
compat="mod_ssl 2.1"
|
|
>
|
|
|
|
<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 renegotation with the
|
|
reconfigured Cipher Suite after the HTTP request was read but before the HTTP
|
|
response is sent.
|
|
|
|
<p>
|
|
An SSL cipher specification in <em>cipher-spec</em> is composed of 4 major
|
|
attributes plus a few extra minor ones:
|
|
|
|
<ul>
|
|
<li><em>Key Exchange Algorithm</em>:<br>
|
|
RSA or Diffie-Hellman variants.
|
|
<p>
|
|
<li><em>Authentication Algorithm</em>:<br>
|
|
RSA, Diffie-Hellman, DSS or none.
|
|
<p>
|
|
<li><em>Cipher/Encryption Algorithm</em>:<br>
|
|
DES, Triple-DES, RC4, RC2, IDEA or none.
|
|
<p>
|
|
<li><em>MAC Digest Algorithm</em>:<br>
|
|
MD5, SHA or SHA1.
|
|
</ul>
|
|
|
|
An SSL cipher can also be an export cipher and is either a 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>
|
|
<float name="table1" caption="Table 1: OpenSSL Cipher Specification Tags">
|
|
<table border="0" cellspacing="0" cellpadding="2" width=598>
|
|
<tr id=D><td><b>Tag</b></td> <td><b>Description</b></td>
|
|
|
|
<tr id=H><td colspan=2><em>Key Exchange Algorithm:</em></td></tr>
|
|
<tr id=D><td><code>kRSA</code></td> <td>RSA key exchange</td></tr>
|
|
<tr id=H><td><code>kDHr</code></td> <td>Diffie-Hellman key exchange with RSA key</td></tr>
|
|
<tr id=D><td><code>kDHd</code></td> <td>Diffie-Hellman key exchange with DSA key</td></tr>
|
|
<tr id=H><td><code>kEDH</code></td> <td>Ephemeral (temp.key) Diffie-Hellman key exchange (no cert)</td> </tr>
|
|
|
|
<tr id=H><td colspan=2><em>Authentication Algorithm:</em></td></tr>
|
|
<tr id=D><td><code>aNULL</code></td> <td>No authentication</td></tr>
|
|
<tr id=H><td><code>aRSA</code></td> <td>RSA authentication</td></tr>
|
|
<tr id=D><td><code>aDSS</code></td> <td>DSS authentication</td> </tr>
|
|
<tr id=H><td><code>aDH</code></td> <td>Diffie-Hellman authentication</td></tr>
|
|
|
|
<tr id=D><td colspan=2><em>Cipher Encoding Algorithm:</em></td></tr></tr>
|
|
<tr id=H><td><code>eNULL</code></td> <td>No encoding</td> </tr>
|
|
<tr id=D><td><code>DES</code></td> <td>DES encoding</td> </tr>
|
|
<tr id=H><td><code>3DES</code></td> <td>Triple-DES encoding</td> </tr>
|
|
<tr id=D><td><code>RC4</code></td> <td>RC4 encoding</td> </tr>
|
|
<tr id=H><td><code>RC2</code></td> <td>RC2 encoding</td> </tr>
|
|
<tr id=D><td><code>IDEA</code></td> <td>IDEA encoding</td> </tr>
|
|
|
|
<tr id=H><td colspan=2><em>MAC Digest Algorithm</em>:</td></tr>
|
|
<tr id=D><td><code>MD5</code></td> <td>MD5 hash function</td></tr>
|
|
<tr id=H><td><code>SHA1</code></td> <td>SHA1 hash function</td></tr>
|
|
<tr id=D><td><code>SHA</code></td> <td>SHA hash function</td> </tr>
|
|
|
|
<tr id=H><td colspan=2><em>Aliases:</em></td></tr>
|
|
<tr id=D><td><code>SSLv2</code></td> <td>all SSL version 2.0 ciphers</td></tr>
|
|
<tr id=H><td><code>SSLv3</code></td> <td>all SSL version 3.0 ciphers</td> </tr>
|
|
<tr id=D><td><code>TLSv1</code></td> <td>all TLS version 1.0 ciphers</td> </tr>
|
|
<tr id=H><td><code>EXP</code></td> <td>all export ciphers</td> </tr>
|
|
<tr id=D><td><code>EXPORT40</code></td> <td>all 40-bit export ciphers only</td> </tr>
|
|
<tr id=H><td><code>EXPORT56</code></td> <td>all 56-bit export ciphers only</td> </tr>
|
|
<tr id=D><td><code>LOW</code></td> <td>all low strength ciphers (no export, single DES)</td></tr>
|
|
<tr id=H><td><code>MEDIUM</code></td> <td>all ciphers with 128 bit encryption</td> </tr>
|
|
<tr id=D><td><code>HIGH</code></td> <td>all ciphers using Triple-DES</td> </tr>
|
|
<tr id=H><td><code>RSA</code></td> <td>all ciphers using RSA key exchange</td> </tr>
|
|
<tr id=D><td><code>DH</code></td> <td>all ciphers using Diffie-Hellman key exchange</td> </tr>
|
|
<tr id=H><td><code>EDH</code></td> <td>all ciphers using Ephemeral Diffie-Hellman key exchange</td> </tr>
|
|
<tr id=D><td><code>ADH</code></td> <td>all ciphers using Anonymous Diffie-Hellman key exchange</td> </tr>
|
|
<tr id=H><td><code>DSS</code></td> <td>all ciphers using DSS authentication</td> </tr>
|
|
<tr id=D><td><code>NULL</code></td> <td>all ciphers using no encryption</td> </tr>
|
|
|
|
</table>
|
|
</float>
|
|
|
|
<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:
|
|
|
|
<ul>
|
|
<li>none: add cipher to list
|
|
<li><code>+</code>: add ciphers to list and pull them to current location in list
|
|
<li><code>-</code>: remove cipher from list (can be added later again)
|
|
<li><code>!</code>: kill cipher from list completely (can <b>not</b> be added later again)
|
|
</ul>
|
|
|
|
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.
|
|
|
|
<blockquote>
|
|
<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>
|
|
</blockquote>
|
|
|
|
The complete list of particular RSA & DH ciphers for SSL is given in <a
|
|
href="#table2">Table 2</a>.
|
|
|
|
<p>
|
|
Example:
|
|
<blockquote>
|
|
<pre>
|
|
# allow only strongest RSA ciphers
|
|
SSLCipherSuite RSA:!EXP:!NULL:+HIGH:+MEDIUM:-LOW
|
|
</pre>
|
|
</blockquote>
|
|
|
|
<p>
|
|
<float name="table2" caption="Table 2: Particular SSL Ciphers">
|
|
<table border="0" cellspacing="0" cellpadding="2" width=598>
|
|
<tr id=D><td><b>Cipher-Tag</b></td> <td><b>Protocol</b></td> <td><b>Key Ex.</b></td> <td><b>Auth.</b></td> <td><b>Enc.</b></td> <td><b>MAC</b></td> <td><b>Type</b></td> </tr>
|
|
|
|
<tr id=H><td colspan=7><em>RSA Ciphers:</em></td></tr>
|
|
<tr id=D><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 id=H><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 id=D><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 id=H><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 id=D><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 id=H><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 id=D><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 id=H><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 id=D><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 id=H><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 id=D><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 id=H><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 id=D><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 id=H><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 id=D><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 id=H><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 id=D><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 id=H><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 id=D><td colspan=7><em>Diffie-Hellman Ciphers:</em></td></tr>
|
|
<tr id=H><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 id=D><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 id=H><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 id=D><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 id=H><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 id=D><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 id=H><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 id=D><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 id=H><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 id=D><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 id=H><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>
|
|
</float>
|
|
|
|
|
|
<!-- SSLCertificateFile --------------------------------------------->
|
|
|
|
<p>
|
|
<br>
|
|
<a name="SSLCertificateFile"></a>
|
|
<h2>SSLCertificateFile</h2>
|
|
|
|
<directive
|
|
name="SSLCertificateFile"
|
|
description="Server PEM-encoded X.509 Certificate file"
|
|
syntax="<code>SSLCertificateFile</code> <em>filename</em>"
|
|
default="<em>None</em>"
|
|
context="server config, virtual host"
|
|
override="<em>Not applicable</em>"
|
|
compat="mod_ssl 2.0"
|
|
>
|
|
|
|
<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:
|
|
<blockquote>
|
|
<pre>
|
|
SSLCertificateFile /usr/local/apache/conf/ssl.crt/server.crt
|
|
</pre>
|
|
</blockquote>
|
|
|
|
|
|
<!-- SSLCertificateKeyFile ------------------------------------------>
|
|
|
|
<p>
|
|
<br>
|
|
<a name="SSLCertificateKeyFile"></a>
|
|
<h2>SSLCertificateKeyFile</h2>
|
|
|
|
<directive
|
|
name="SSLCertificateKeyFile"
|
|
description="Server PEM-encoded Private Key file"
|
|
syntax="<code>SSLCertificateKeyFile</code> <em>filename</em>"
|
|
default="<em>None</em>"
|
|
context="server config, virtual host"
|
|
override="<em>Not applicable</em>"
|
|
compat="mod_ssl 2.0"
|
|
>
|
|
|
|
<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
|
|
<code>SSLCertificateFile</code>, use this additional directive to point to the
|
|
file with the stand-alone Private Key. When <code>SSLCertificateFile</code>
|
|
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:
|
|
<blockquote>
|
|
<pre>
|
|
SSLCertificateKeyFile /usr/local/apache/conf/ssl.key/server.key
|
|
</pre>
|
|
</blockquote>
|
|
|
|
|
|
<!-- SSLCertificateChainFile ---------------------------------------->
|
|
|
|
<p>
|
|
<br>
|
|
<a name="SSLCertificateChainFile"></a>
|
|
<h2>SSLCertificateChainFile</h2>
|
|
|
|
<directive
|
|
name="SSLCertificateChainFile"
|
|
description="File of PEM-encoded Server CA Certificates"
|
|
syntax="<code>SSLCertificateChainFile</code> <em>filename</em>"
|
|
default="<em>None</em>"
|
|
context="server config, virtual host"
|
|
override="<em>Not applicable</em>"
|
|
compat="mod_ssl 2.3.6"
|
|
>
|
|
|
|
<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 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>
|
|
This should be used alternatively and/or additionally to <a
|
|
href="#SSLCACertificatePath">SSLCACertificatePath</a> 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 <a
|
|
href="#SSLCACertificatePath">SSLCACertificatePath</a> 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. That's usually not one expect.
|
|
|
|
<p>
|
|
But be careful: Providing the certificate chain works only if you are using a
|
|
<i>single</i> (either RSA <i>or</i> DSA) based server certificate. If you are
|
|
using a coupled RSA+DSA certificate pair, this will work only if actually both
|
|
certificates use the <i>same</i> certificate chain. Else the browsers will be
|
|
confused in this situation.
|
|
|
|
<p>
|
|
Example:
|
|
<blockquote>
|
|
<pre>
|
|
SSLCertificateChainFile /usr/local/apache/conf/ssl.crt/ca.crt
|
|
</pre>
|
|
</blockquote>
|
|
|
|
|
|
<!-- SSLCACertificatePath ------------------------------------------->
|
|
|
|
<p>
|
|
<br>
|
|
<a name="SSLCACertificatePath"></a>
|
|
<h2>SSLCACertificatePath</h2>
|
|
|
|
<directive
|
|
name="SSLCACertificatePath"
|
|
description="Directory of PEM-encoded CA Certificates for Client Auth."
|
|
syntax="<code>SSLCACertificatePath</code> <em>directory</em>"
|
|
default="<em>None</em>"
|
|
context="server config, virtual host"
|
|
override="<em>Not applicable</em>"
|
|
compat="mod_ssl 2.0"
|
|
>
|
|
|
|
<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>
|
|
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
|
|
<i>hash-value</i><tt>.N</tt>. 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:
|
|
<blockquote>
|
|
<pre>
|
|
SSLCACertificatePath /usr/local/apache/conf/ssl.crt/
|
|
</pre>
|
|
</blockquote>
|
|
|
|
|
|
<!-- SSLCACertificateFile ------------------------------------------->
|
|
|
|
<p>
|
|
<br>
|
|
<a name="SSLCACertificateFile"></a>
|
|
<h2>SSLCACertificateFile</h2>
|
|
|
|
<directive
|
|
name="SSLCACertificateFile"
|
|
description="File of concatenated PEM-encoded CA Certificates for Client Auth."
|
|
syntax="<code>SSLCACertificateFile</code> <em>filename</em>"
|
|
default="<em>None</em>"
|
|
context="server config, virtual host"
|
|
override="<em>Not applicable</em>"
|
|
compat="mod_ssl 2.0"
|
|
>
|
|
|
|
<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 <a
|
|
href="#SSLCACertificatePath">SSLCACertificatePath</a>.
|
|
|
|
<p>
|
|
Example:
|
|
<blockquote>
|
|
<pre>
|
|
SSLCACertificateFile /usr/local/apache/conf/ssl.crt/ca-bundle-client.crt
|
|
</pre>
|
|
</blockquote>
|
|
|
|
|
|
<!-- SSLCARevocationPath -------------------------------------------->
|
|
|
|
<p>
|
|
<br>
|
|
<a name="SSLCARevocationPath"></a>
|
|
<h2>SSLCARevocationPath</h2>
|
|
|
|
<directive
|
|
name="SSLCARevocationPath"
|
|
description="Directory of PEM-encoded CA CRLs for Client Auth."
|
|
syntax="<code>SSLCARevocationPath</code> <em>directory</em>"
|
|
default="<em>None</em>"
|
|
context="server config, virtual host"
|
|
override="<em>Not applicable</em>"
|
|
compat="mod_ssl 2.3"
|
|
>
|
|
|
|
<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>
|
|
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
|
|
<i>hash-value</i><tt>.rN</tt>. 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:
|
|
<blockquote>
|
|
<pre>
|
|
SSLCARevocationPath /usr/local/apache/conf/ssl.crl/
|
|
</pre>
|
|
</blockquote>
|
|
|
|
|
|
<!-- SSLCARevocationFile -------------------------------------------->
|
|
|
|
<p>
|
|
<br>
|
|
<a name="SSLCARevocationFile"></a>
|
|
<h2>SSLCARevocationFile</h2>
|
|
|
|
<directive
|
|
name="SSLCARevocationFile"
|
|
description="File of concatenated PEM-encoded CA CRLs for Client Auth."
|
|
syntax="<code>SSLCARevocationFile</code> <em>filename</em>"
|
|
default="<em>None</em>"
|
|
context="server config, virtual host"
|
|
override="<em>Not applicable</em>"
|
|
compat="mod_ssl 2.3"
|
|
>
|
|
|
|
<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 <a href="#SSLCARevocationPath">SSLCARevocationPath</a>.
|
|
|
|
<p>
|
|
Example:
|
|
<blockquote>
|
|
<pre>
|
|
SSLCARevocationFile /usr/local/apache/conf/ssl.crl/ca-bundle-client.crl
|
|
</pre>
|
|
</blockquote>
|
|
|
|
|
|
<!-- SSLVerifyClient ------------------------------------------------->
|
|
|
|
<p>
|
|
<br>
|
|
<a name="SSLVerifyClient"></a>
|
|
<h2>SSLVerifyClient</h2>
|
|
|
|
<directive
|
|
name="SSLVerifyClient"
|
|
description="Type of Client Certificate verification"
|
|
syntax="<code>SSLVerifyClient</code> <em>level</em>"
|
|
default="<code>SSLVerifyClient none</code>"
|
|
context="server config, virtual host, directory, .htaccess"
|
|
override="AuthConfig"
|
|
compat="mod_ssl 2.0"
|
|
>
|
|
|
|
<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 renegotation with the
|
|
reconfigured client verification level after the HTTP request was read but
|
|
before the HTTP response is sent.
|
|
|
|
<p>
|
|
The following levels are available for <em>level</em>:
|
|
|
|
<ul>
|
|
<li><strong>none</strong>:
|
|
no client Certificate is required at all
|
|
<li><strong>optional</strong>:
|
|
the client <em>may</em> present a valid Certificate
|
|
<li><strong>require</strong>:
|
|
the client <em>has to</em> present a valid Certificate
|
|
<li><strong>optional_no_ca</strong>:
|
|
the client may present a valid Certificate<br>
|
|
but it need not to be (successfully) verifiable.
|
|
</ul>
|
|
|
|
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:
|
|
<blockquote>
|
|
<pre>
|
|
SSLVerifyClient require
|
|
</pre>
|
|
</blockquote>
|
|
|
|
|
|
<!-- SSLVerifyDepth ------------------------------------------------->
|
|
|
|
<p>
|
|
<br>
|
|
<a name="SSLVerifyDepth"></a>
|
|
<h2>SSLVerifyDepth</h2>
|
|
|
|
<directive
|
|
name="SSLVerifyDepth"
|
|
description="Maximum depth of CA Certificates in Client Certificate verification"
|
|
syntax="<code>SSLVerifyDepth</code> <em>number</em>"
|
|
default="<code>SSLVerifyDepth 1</code>"
|
|
context="server config, virtual host, directory, .htaccess"
|
|
override="AuthConfig"
|
|
compat="mod_ssl 2.0"
|
|
>
|
|
|
|
<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 renegotation with the reconfigured client verification depth after the
|
|
HTTP request was read but before the HTTP response is sent.
|
|
|
|
<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
|
|
<code>SSLCACertificatePath</code>), etc.
|
|
|
|
<p>
|
|
Example:
|
|
<blockquote>
|
|
<pre>
|
|
SSLVerifyDepth 10
|
|
</pre>
|
|
</blockquote>
|
|
|
|
|
|
<!-- SSLLog --------------------------------------------------------->
|
|
|
|
<p>
|
|
<br>
|
|
<a name="SSLLog"></a>
|
|
<h2>SSLLog</h2>
|
|
|
|
<directive
|
|
name="SSLLog"
|
|
description="Where to write the dedicated SSL engine logfile"
|
|
syntax="<code>SSLLog</code> <em>filename</em>"
|
|
default="<em>None</em>"
|
|
context="server config, virtual host"
|
|
override="<em>Not applicable</em>"
|
|
compat="mod_ssl 2.1"
|
|
>
|
|
|
|
<p>
|
|
This directive sets the name of the dedicated SSL protocol engine logfile.
|
|
Error type messages are additionally duplicated to the general Apache error
|
|
log file (directive <code>ErrorLog</code>). Put this somewhere where it cannot
|
|
be used for symlink attacks on a real server (i.e. somewhere where only root
|
|
can write). If the <em>filename</em> does not begin with a slash
|
|
('<code>/</code>') then it is assumed to be relative to the <em>Server
|
|
Root</em>. If <em>filename</em> begins with a bar ('<code>|</code>') then the
|
|
following string is assumed to be a path to an executable program to which a
|
|
reliable pipe can be established. The directive should occur only once per
|
|
virtual server config.
|
|
|
|
<p>
|
|
Example:
|
|
<blockquote>
|
|
<pre>
|
|
SSLLog /usr/local/apache/logs/ssl_engine_log
|
|
</pre>
|
|
</blockquote>
|
|
|
|
|
|
<!-- SSLLogLevel ---------------------------------------------------->
|
|
|
|
<p>
|
|
<br>
|
|
<a name="SSLLogLevel"></a>
|
|
<h2>SSLLogLevel</h2>
|
|
|
|
<directive
|
|
name="SSLLogLevel"
|
|
description="Logging level for the dedicated SSL engine logfile"
|
|
syntax="<code>SSLLogLevel</code> <em>level</em>"
|
|
default="<code>SSLLogLevel none</code>"
|
|
context="server config, virtual host"
|
|
override="<em>Not applicable</em>"
|
|
compat="mod_ssl 2.1"
|
|
>
|
|
|
|
<p>
|
|
This directive sets the verbosity degree of the dedicated SSL protocol engine
|
|
logfile. The <em>level</em> is one of the following (in ascending order where
|
|
higher levels include lower levels):
|
|
|
|
<ul>
|
|
<li><code>none</code><br>
|
|
no dedicated SSL logging is done, but messages of level
|
|
``<code>error</code>'' are still written to the general Apache error
|
|
logfile.
|
|
<p>
|
|
<li><code>error</code><br>
|
|
log messages of error type only, i.e. messages which show fatal situations
|
|
(processing is stopped). Those messages are also duplicated to the
|
|
general Apache error logfile.
|
|
<p>
|
|
<li><code>warn</code><br>
|
|
log also warning messages, i.e. messages which show non-fatal problems
|
|
(processing is continued).
|
|
<p>
|
|
<li><code>info</code><br>
|
|
log also informational messages, i.e. messages which show major
|
|
processing steps.
|
|
<p>
|
|
<li><code>trace</code><br>
|
|
log also trace messages, i.e. messages which show minor processing steps.
|
|
<p>
|
|
<li><code>debug</code><br>
|
|
log also debugging messages, i.e. messages which show development and
|
|
low-level I/O information.
|
|
</ul>
|
|
|
|
<p>
|
|
Example:
|
|
<blockquote>
|
|
<pre>
|
|
SSLLogLevel warn
|
|
</pre>
|
|
</blockquote>
|
|
|
|
|
|
<!-- SSLOptions ----------------------------------------------------->
|
|
|
|
<p>
|
|
<br>
|
|
<a name="SSLOptions"></a>
|
|
<h2>SSLOptions</h2>
|
|
|
|
<directive
|
|
name="SSLOptions"
|
|
description="Configure various SSL engine run-time options"
|
|
syntax="<code>SSLOptions</code> [+-]<em>option</em> ..."
|
|
default="<em>None</em>"
|
|
context="server config, virtual host, directory, .htaccess"
|
|
override="Options"
|
|
compat="mod_ssl 2.1"
|
|
>
|
|
|
|
<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>
|
|
The available <em>option</em>s are:
|
|
|
|
<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><code>CompatEnvVars</code>
|
|
<p>
|
|
When this option is enabled, additional CGI/SSI environment variables are
|
|
created for backward compatibility to other Apache SSL solutions. Look in
|
|
the <a href="ssl_compat.html">Compatibility</a> chapter for details
|
|
on the particular variables generated.
|
|
<p>
|
|
<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><i>n</i> (with <i>n</i> = 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><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...$Owx8s2/m9/gfkcRVXzgoE/</code>''.
|
|
<p>
|
|
<li><code>StrictRequire</code>
|
|
<p>
|
|
This <i>forces</i> forbidden access when <code>SSLRequireSSL</code> or
|
|
<code>SSLRequire</code> successfully decided that access should be
|
|
forbidden. Usually the default is that in the case where a ``<code>Satisfy
|
|
any</code>'' directive is used, and other access restrictions are passed,
|
|
denial of access due to <code>SSLRequireSSL</code> or
|
|
<code>SSLRequire</code> is overridden (because that's how the Apache
|
|
<tt>Satisfy</tt> mechanism should work.) But for strict access restriction
|
|
you can use <code>SSLRequireSSL</code> and/or <code>SSLRequire</code> in
|
|
combination with an ``<code>SSLOptions +StrictRequire</code>''. Then an
|
|
additional ``<code>Satisfy Any</code>'' has no chance once mod_ssl has
|
|
decided to deny access.
|
|
<p>
|
|
<li><code>OptRenegotiate</code>
|
|
<p>
|
|
This enables optimized SSL connection renegotiation handling when SSL
|
|
directives are used in per-directory context. By default a strict
|
|
scheme is enabled where <i>every</i> per-directory reconfiguration of
|
|
SSL parameters causes a <i>full</i> SSL renegotiation handshake. When this
|
|
option is used mod_ssl tries to avoid unnecessary handshakes by doing more
|
|
granular (but still safe) parameter checks. Nevertheless these granular
|
|
checks sometimes maybe not what the user expects, so enable this on a
|
|
per-directory basis only, please.
|
|
</ul>
|
|
|
|
<p>
|
|
Example:
|
|
<blockquote>
|
|
<pre>
|
|
SSLOptions +FakeBasicAuth -StrictRequire
|
|
<Files ~ "\.(cgi|shtml)$">
|
|
SSLOptions +StdEnvVars +CompatEnvVars -ExportCertData
|
|
<Files>
|
|
</pre>
|
|
</blockquote>
|
|
|
|
|
|
<!-- SSLRequireSSL -------------------------------------------------->
|
|
|
|
<p>
|
|
<br>
|
|
<a name="SSLRequireSSL"></a>
|
|
<h2>SSLRequireSSL</h2>
|
|
|
|
<directive
|
|
name="SSLRequireSSL"
|
|
description="Deny access when SSL is not used for the HTTP request"
|
|
syntax="<code>SSLRequireSSL</code>"
|
|
default="<em>None</em>"
|
|
context="directory, .htaccess"
|
|
override="AuthConfig"
|
|
compat="mod_ssl 2.0"
|
|
>
|
|
|
|
<p>
|
|
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:
|
|
<blockquote>
|
|
<pre>
|
|
SSLRequireSSL
|
|
</pre>
|
|
</blockquote>
|
|
|
|
|
|
<!-- SSLRequire ----------------------------------------------------->
|
|
|
|
<p>
|
|
<br>
|
|
<a name="SSLRequire"></a>
|
|
<h2>SSLRequire</h2>
|
|
|
|
<directive
|
|
name="SSLRequire"
|
|
description="Allow access only when an arbitrarily complex boolean expression is true"
|
|
syntax="<code>SSLRequire</code> <em>expression</em>"
|
|
default="<em>None</em>"
|
|
context="directory, .htaccess"
|
|
override="AuthConfig"
|
|
compat="mod_ssl 2.1"
|
|
>
|
|
|
|
<p>
|
|
This directive specifies a general access requirement which has to be
|
|
fulfilled in order to allow access. It's a very powerful directive because the
|
|
requirement specification is an arbitrarily complex boolean expression
|
|
containing any number of access checks.
|
|
|
|
<p>
|
|
The <em>expression</em> must match the following syntax (given as a BNF
|
|
grammar notation):
|
|
|
|
<blockquote>
|
|
<pre>
|
|
expr ::= "<b>true</b>" | "<b>false</b>"
|
|
| "<b>!</b>" expr
|
|
| expr "<b>&&</b>" expr
|
|
| expr "<b>||</b>" expr
|
|
| "<b>(</b>" expr "<b>)</b>"
|
|
| comp
|
|
|
|
comp ::= word "<b>==</b>" word | word "<b>eq</b>" word
|
|
| word "<b>!=</b>" word | word "<b>ne</b>" word
|
|
| word "<b><</b>" word | word "<b>lt</b>" word
|
|
| word "<b><=</b>" word | word "<b>le</b>" word
|
|
| word "<b>></b>" word | word "<b>gt</b>" word
|
|
| word "<b>>=</b>" word | word "<b>ge</b>" word
|
|
| word "<b>in</b>" "<b>{</b>" wordlist "<b>}</b>"
|
|
| word "<b>=~</b>" regex
|
|
| word "<b>!~</b>" regex
|
|
|
|
wordlist ::= word
|
|
| wordlist "<b>,</b>" word
|
|
|
|
word ::= digit
|
|
| cstring
|
|
| variable
|
|
| function
|
|
|
|
digit ::= [0-9]+
|
|
cstring ::= "..."
|
|
variable ::= "<b>%{</b>" varname "<b>}</b>"
|
|
function ::= funcname "<b>(</b>" funcargs "<b>)</b>"
|
|
</pre>
|
|
</blockquote>
|
|
|
|
while for <code>varname</code> any variable from <a href="#table3">Table 3</a>
|
|
can be used. Finally for <code>funcname</code> the following functions
|
|
are available:
|
|
|
|
<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.
|
|
</ul>
|
|
|
|
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:
|
|
<blockquote>
|
|
<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>
|
|
</blockquote>
|
|
|
|
<float name="table3" caption="Table 3: Available Variables for SSLRequire">
|
|
<table><tr><td>
|
|
<em>Standard CGI/1.0 and Apache variables:</em>
|
|
<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
|
|
HTTP:headername SERVER_NAME TIME_MIN
|
|
THE_REQUEST SERVER_PORT TIME_SEC
|
|
REQUEST_METHOD SERVER_PROTOCOL TIME_WDAY
|
|
REQUEST_SCHEME REMOTE_ADDR TIME
|
|
REQUEST_URI REMOTE_USER ENV:<b>variablename</b>
|
|
REQUEST_FILENAME
|
|
</pre>
|
|
|
|
<em>SSL-related variables:</em>
|
|
<pre>
|
|
HTTPS SSL_CLIENT_M_VERSION SSL_SERVER_M_VERSION
|
|
SSL_CLIENT_M_SERIAL SSL_SERVER_M_SERIAL
|
|
SSL_PROTOCOL SSL_CLIENT_V_START SSL_SERVER_V_START
|
|
SSL_SESSION_ID SSL_CLIENT_V_END SSL_SERVER_V_END
|
|
SSL_CIPHER SSL_CLIENT_S_DN SSL_SERVER_S_DN
|
|
SSL_CIPHER_EXPORT SSL_CLIENT_S_DN_C SSL_SERVER_S_DN_C
|
|
SSL_CIPHER_ALGKEYSIZE SSL_CLIENT_S_DN_ST SSL_SERVER_S_DN_ST
|
|
SSL_CIPHER_USEKEYSIZE SSL_CLIENT_S_DN_L SSL_SERVER_S_DN_L
|
|
SSL_VERSION_LIBRARY SSL_CLIENT_S_DN_O SSL_SERVER_S_DN_O
|
|
SSL_VERSION_INTERFACE SSL_CLIENT_S_DN_OU SSL_SERVER_S_DN_OU
|
|
SSL_CLIENT_S_DN_CN SSL_SERVER_S_DN_CN
|
|
SSL_CLIENT_S_DN_T SSL_SERVER_S_DN_T
|
|
SSL_CLIENT_S_DN_I SSL_SERVER_S_DN_I
|
|
SSL_CLIENT_S_DN_G SSL_SERVER_S_DN_G
|
|
SSL_CLIENT_S_DN_S SSL_SERVER_S_DN_S
|
|
SSL_CLIENT_S_DN_D SSL_SERVER_S_DN_D
|
|
SSL_CLIENT_S_DN_UID SSL_SERVER_S_DN_UID
|
|
SSL_CLIENT_S_DN_Email SSL_SERVER_S_DN_Email
|
|
SSL_CLIENT_I_DN SSL_SERVER_I_DN
|
|
SSL_CLIENT_I_DN_C SSL_SERVER_I_DN_C
|
|
SSL_CLIENT_I_DN_ST SSL_SERVER_I_DN_ST
|
|
SSL_CLIENT_I_DN_L SSL_SERVER_I_DN_L
|
|
SSL_CLIENT_I_DN_O SSL_SERVER_I_DN_O
|
|
SSL_CLIENT_I_DN_OU SSL_SERVER_I_DN_OU
|
|
SSL_CLIENT_I_DN_CN SSL_SERVER_I_DN_CN
|
|
SSL_CLIENT_I_DN_T SSL_SERVER_I_DN_T
|
|
SSL_CLIENT_I_DN_I SSL_SERVER_I_DN_I
|
|
SSL_CLIENT_I_DN_G SSL_SERVER_I_DN_G
|
|
SSL_CLIENT_I_DN_S SSL_SERVER_I_DN_S
|
|
SSL_CLIENT_I_DN_D SSL_SERVER_I_DN_D
|
|
SSL_CLIENT_I_DN_UID SSL_SERVER_I_DN_UID
|
|
SSL_CLIENT_I_DN_Email SSL_SERVER_I_DN_Email
|
|
SSL_CLIENT_A_SIG SSL_SERVER_A_SIG
|
|
SSL_CLIENT_A_KEY SSL_SERVER_A_KEY
|
|
SSL_CLIENT_CERT SSL_SERVER_CERT
|
|
SSL_CLIENT_CERT_CHAIN<b>n</b>
|
|
SSL_CLIENT_VERIFY
|
|
</pre>
|
|
</td></tr></table>
|
|
</float>
|
|
|
|
<br>
|
|
<br>
|
|
<p>
|
|
<h1>Additional Features</h1>
|
|
|
|
<h2>Environment Variables</h2>
|
|
|
|
This module provides a lot of SSL information as additional environment
|
|
variables to the SSI and CGI namespace. The generated variables are listed in
|
|
<a href="#table4">Table 4</a>. For backward compatibility the information can
|
|
be made available under different names, too. Look in the <a
|
|
href="ssl_compat.html">Compatibility</a> chapter for details on the
|
|
compatibility variables.
|
|
|
|
<p>
|
|
<float name="table4" caption="Table 4: SSI/CGI Environment Variables">
|
|
<table border="0" cellspacing="0" cellpadding="2" width=598>
|
|
<tr id=H>
|
|
<td><b>Variable Name:</b></td>
|
|
<td><b>Value Type:</b></td>
|
|
<td><b>Description:</b></td>
|
|
</tr>
|
|
<tr id=D><td><code>HTTPS</code></td> <td>flag</td> <td>HTTPS is being used.</td></tr>
|
|
<tr id=H><td><code>SSL_PROTOCOL</code></td> <td>string</td> <td>The SSL protocol version (SSLv2, SSLv3, TLSv1)</td></tr>
|
|
<tr id=H><td><code>SSL_SESSION_ID</code></td> <td>string</td> <td>The hex-encoded SSL session id</td></tr>
|
|
<tr id=D><td><code>SSL_CIPHER</code></td> <td>string</td> <td>The cipher specification name</td></tr>
|
|
<tr id=D><td><code>SSL_CIPHER_EXPORT</code></td> <td>string</td> <td><code>true</code> if cipher is an export cipher</td></tr>
|
|
<tr id=H><td><code>SSL_CIPHER_USEKEYSIZE</code></td> <td>number</td> <td>Number of cipher bits (actually used)</td></tr>
|
|
<tr id=D><td><code>SSL_CIPHER_ALGKEYSIZE</code></td> <td>number</td> <td>Number of cipher bits (possible)</td></tr>
|
|
<tr id=H><td><code>SSL_VERSION_INTERFACE</code></td> <td>string</td> <td>The mod_ssl program version</td></tr>
|
|
<tr id=D><td><code>SSL_VERSION_LIBRARY</code></td> <td>string</td> <td>The OpenSSL program version</td></tr>
|
|
<tr id=H><td><code>SSL_CLIENT_M_VERSION</code></td> <td>string</td> <td>The version of the client certificate</td></tr>
|
|
<tr id=D><td><code>SSL_CLIENT_M_SERIAL</code></td> <td>string</td> <td>The serial of the client certificate</td></tr>
|
|
<tr id=H><td><code>SSL_CLIENT_S_DN</code></td> <td>string</td> <td>Subject DN in client's certificate</td></tr>
|
|
<tr id=D><td><code>SSL_CLIENT_S_DN_</code><em>x509</em></td> <td>string</td> <td>Component of client's Subject DN</td></tr>
|
|
<tr id=H><td><code>SSL_CLIENT_I_DN</code></td> <td>string</td> <td>Issuer DN of client's certificate</td></tr>
|
|
<tr id=D><td><code>SSL_CLIENT_I_DN_</code><em>x509</em></td> <td>string</td> <td>Component of client's Issuer DN</td></tr>
|
|
<tr id=H><td><code>SSL_CLIENT_V_START</code></td> <td>string</td> <td>Validity of client's certificate (start time)</td></tr>
|
|
<tr id=D><td><code>SSL_CLIENT_V_END</code></td> <td>string</td> <td>Validity of client's certificate (end time)</td></tr>
|
|
<tr id=H><td><code>SSL_CLIENT_A_SIG</code></td> <td>string</td> <td>Algorithm used for the signature of client's certificate</td></tr>
|
|
<tr id=D><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 id=H><td><code>SSL_CLIENT_CERT</code></td> <td>string</td> <td>PEM-encoded client certificate</td></tr>
|
|
<tr id=D><td><code>SSL_CLIENT_CERT_CHAIN</code><i>n</i></td> <td>string</td> <td>PEM-encoded certificates in client certificate chain</td></tr>
|
|
<tr id=H><td><code>SSL_CLIENT_VERIFY</code></td> <td>string</td> <td><tt>NONE</tt>, <tt>SUCCESS</tt>, <tt>GENEROUS</tt> or <tt>FAILED:</tt><i>reason</i></td></tr>
|
|
<tr id=D><td><code>SSL_SERVER_M_VERSION</code></td> <td>string</td> <td>The version of the server certificate</td></tr>
|
|
<tr id=H><td><code>SSL_SERVER_M_SERIAL</code></td> <td>string</td> <td>The serial of the server certificate</td></tr>
|
|
<tr id=D><td><code>SSL_SERVER_S_DN</code></td> <td>string</td> <td>Subject DN in server's certificate</td></tr>
|
|
<tr id=H><td><code>SSL_SERVER_S_DN_</code><em>x509</em></td> <td>string</td> <td>Component of server's Subject DN</td></tr>
|
|
<tr id=D><td><code>SSL_SERVER_I_DN</code></td> <td>string</td> <td>Issuer DN of server's certificate</td></tr>
|
|
<tr id=H><td><code>SSL_SERVER_I_DN_</code><em>x509</em></td> <td>string</td> <td>Component of server's Issuer DN</td></tr>
|
|
<tr id=D><td><code>SSL_SERVER_V_START</code></td> <td>string</td> <td>Validity of server's certificate (start time)</td></tr>
|
|
<tr id=H><td><code>SSL_SERVER_V_END</code></td> <td>string</td> <td>Validity of server's certificate (end time)</td></tr>
|
|
<tr id=D><td><code>SSL_SERVER_A_SIG</code></td> <td>string</td> <td>Algorithm used for the signature of server's certificate</td></tr>
|
|
<tr id=H><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 id=D><td><code>SSL_SERVER_CERT</code></td> <td>string</td> <td>PEM-encoded server certificate</td></tr>
|
|
</table>
|
|
[ where <em>x509</em> is a component of a X.509 DN:
|
|
<code>C,ST,L,O,OU,CN,T,I,G,S,D,UID,Email</code> ]
|
|
</float>
|
|
|
|
|
|
<p>
|
|
<br>
|
|
<h2>Custom Log Formats</h2>
|
|
|
|
When mod_ssl 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 <a
|
|
href="../mod_log_config.html">mod_log_config</a>. 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 <a href="#table4">Table 4</a>.
|
|
|
|
<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_compat.html">Compatibility</a> chapter.
|
|
|
|
<p>
|
|
Example:
|
|
<blockquote>
|
|
<pre>
|
|
CustomLog logs/ssl_request_log \\
|
|
"%t %h %{SSL_PROTOCOL}x %{SSL_CIPHER}x \"%r\" %b"
|
|
</pre>
|
|
</blockquote>
|
|
|