Apache HTTP Server Version 2.4
Apache HTTP Server Version 2.4
This documented is intended to get you started, and get a few things working. You are strongly encouraged to read the rest of the SSL documentation, and arrive at a deeper understanding of the material, before progressing to the advanced techniques.
Your SSL configuration will need to contain, at minimum, the following directives.
LoadModule ssl_module modules/mod_ssl.so
Listen 443
<VirtualHost *:443>
ServerName www.example.com
SSLEngine on
SSLCertificateFile /path/to/www.example.com.cert
SSLCertificateKeyFile /path/to/www.example.com.key
</VirtualHost>
The following enables only the strongest ciphers:
SSLCipherSuite HIGH:!aNULL:!MD5
While with the following configuration you specify a preference for specific speed-optimized ciphers (which will be selected by mod_ssl, provided that they are supported by the client):
SSLCipherSuite RC4-SHA:AES128-SHA:HIGH:!aNULL:!MD5 SSLHonorCipherOrder on
Obviously, a server-wide SSLCipherSuite which restricts
ciphers to the strong variants, isn't the answer here. However,
mod_ssl can be reconfigured within Location
blocks, to give a per-directory solution, and can automatically force
a renegotiation of the SSL parameters to meet the new configuration.
This can be done as follows:
# be liberal in general SSLCipherSuite ALL:!aNULL:RC4+RSA:+HIGH:+MEDIUM:+LOW:+EXP:+eNULL <Location /strong/area> # but https://hostname/strong/area/ and below # requires strong ciphers SSLCipherSuite HIGH:!aNULL:!MD5 </Location>
When you know all of your users (eg, as is often the case on a corporate
Intranet), you can require plain certificate authentication. All you
need to do is to create client certificates signed by your own CA
certificate (ca.crt) and then verify the clients against this
certificate.
# require a client certificate which has to be directly # signed by our CA certificate in ca.crt SSLVerifyClient require SSLVerifyDepth 1 SSLCACertificateFile conf/ssl.crt/ca.crt
To force clients to authenticate using certificates for a particular URL,
you can use the per-directory reconfiguration features of
mod_ssl:
SSLVerifyClient none SSLCACertificateFile conf/ssl.crt/ca.crt <Location /secure/area> SSLVerifyClient require SSLVerifyDepth 1 </Location>
The key to doing this is checking that part of the client certificate
matches what you expect. Usually this means checking all or part of the
Distinguished Name (DN), to see if it contains some known string.
There are two ways to do this, using either mod_auth_basic or
SSLRequire.
The mod_auth_basic method is generally required when
the certificates are completely arbitrary, or when their DNs have
no common fields (usually the organisation, etc.). In this case,
you should establish a password database containing all
clients allowed, as follows:
SSLVerifyClient none
SSLCACertificateFile conf/ssl.crt/ca.crt
SSLCACertificatePath conf/ssl.crt
<Directory /usr/local/apache2/htdocs/secure/area>
SSLVerifyClient require
SSLVerifyDepth 5
SSLOptions +FakeBasicAuth
SSLRequireSSL
AuthName "Snake Oil Authentication"
AuthType Basic
AuthBasicProvider file
AuthUserFile /usr/local/apache2/conf/httpd.passwd
Require valid-user
</Directory>
The password used in this example is the DES encrypted string "password".
See the SSLOptions docs for more
information.
/C=DE/L=Munich/O=Snake Oil, Ltd./OU=Staff/CN=Foo:xxj31ZMTZzkVA /C=US/L=S.F./O=Snake Oil, Ltd./OU=CA/CN=Bar:xxj31ZMTZzkVA /C=US/L=L.A./O=Snake Oil, Ltd./OU=Dev/CN=Quux:xxj31ZMTZzkVA
When your clients are all part of a common hierarchy, which is encoded
into the DN, you can match them more easily using SSLRequire, as follows:
SSLVerifyClient none
SSLCACertificateFile conf/ssl.crt/ca.crt
SSLCACertificatePath conf/ssl.crt
<Directory /usr/local/apache2/htdocs/secure/area>
SSLVerifyClient require
SSLVerifyDepth 5
SSLOptions +FakeBasicAuth
SSLRequireSSL
SSLRequire %{SSL_CLIENT_S_DN_O} eq "Snake Oil, Ltd." \
and %{SSL_CLIENT_S_DN_OU} in {"Staff", "CA", "Dev"}
</Directory>
These examples presume that clients on the Intranet have IPs in the range
192.168.1.0/24, and that the part of the Intranet website you want to allow
internet access to is /usr/local/apache2/htdocs/subarea.
This configuration should remain outside of your HTTPS virtual host, so
that it applies to both HTTPS and HTTP.
SSLCACertificateFile conf/ssl.crt/company-ca.crt
<Directory /usr/local/apache2/htdocs>
# Outside the subarea only Intranet access is granted
Require ip 192.168.1.0/24
</Directory>
<Directory /usr/local/apache2/htdocs/subarea>
# Inside the subarea any Intranet access is allowed
# but from the Internet only HTTPS + Strong-Cipher + Password
# or the alternative HTTPS + Strong-Cipher + Client-Certificate
# If HTTPS is used, make sure a strong cipher is used.
# Additionally allow client certs as alternative to basic auth.
SSLVerifyClient optional
SSLVerifyDepth 1
SSLOptions +FakeBasicAuth +StrictRequire
SSLRequire %{SSL_CIPHER_USEKEYSIZE} >= 128
# Force clients from the Internet to use HTTPS
RewriteEngine on
RewriteCond %{REMOTE_ADDR} !^192\.168\.1\.[0-9]+$
RewriteCond %{HTTPS} !=on
RewriteRule . - [F]
# Allow Network Access and/or Basic Auth
Satisfy any
# Network Access Control
Require ip 192.168.1.0/24
# HTTP Basic Authentication
AuthType basic
AuthName "Protected Intranet Area"
AuthBasicProvider file
AuthUserFile conf/protected.passwd
Require valid-user
</Directory>