Modules |Directives |FAQ |Glossary |Sitemap
Apache HTTP Server Version 2.4
| Description: | User authentication using MD5 Digest Authentication |
|---|---|
| Status: | Extension |
| Module Identifier: | auth_digest_module |
| Source File: | mod_auth_digest.c |
This module implements HTTP Digest Authentication (RFC2617), and provides an alternative tomod_auth_basic where the password is not transmitted as cleartext. However, this doesnot lead to a significant security advantage over basic authentication. On the other hand, the password storage on the server is much less secure with digest authentication than with basic authentication. Therefore, using basic auth and encrypting the whole connection usingmod_ssl is a much better alternative.
AuthDigestAlgorithmAuthDigestDomainAuthDigestNonceLifetimeAuthDigestProviderAuthDigestQopAuthDigestShmemSize
To use MD5 Digest authentication, configure the location to be protected as shown in the below example:
<Location "/private/"> AuthType Digest AuthName "private area" AuthDigestDomain "/private/" "http://mirror.my.dom/private2/" AuthDigestProvider file AuthUserFile "/web/auth/.digest_pw" Require valid-user</Location>
AuthDigestDomain should list the locations that will be protected by this configuration.
The password file referenced in theAuthUserFile directive may be created and managed using thehtdigest tool.
Digest authentication was intended to be more secure than basic authentication, but no longer fulfills that design goal. A man-in-the-middle attacker can trivially force the browser to downgrade to basic authentication. And even a passive eavesdropper can brute-force the password using today's graphics hardware, because the hashing algorithm used by digest authentication is too fast. Another problem is that the storage of the passwords on the server is insecure. The contents of a stolen htdigest file can be used directly for digest authentication. Therefore usingmod_ssl to encrypt the whole connection is strongly recommended.
mod_auth_digest only works properly on platforms where APR supports shared memory.
| Description: | Selects the algorithm used to calculate the challenge andresponse hashes in digest authentication |
|---|---|
| Syntax: | AuthDigestAlgorithm MD5|MD5-sess |
| Default: | AuthDigestAlgorithm MD5 |
| Context: | directory, .htaccess |
| Override: | AuthConfig |
| Status: | Extension |
| Module: | mod_auth_digest |
TheAuthDigestAlgorithm directive selects the algorithm used to calculate the challenge and response hashes.
MD5-sess is not correctly implemented yet.| Description: | URIs that are in the same protection space for digestauthentication |
|---|---|
| Syntax: | AuthDigestDomainURI [URI] ... |
| Context: | directory, .htaccess |
| Override: | AuthConfig |
| Status: | Extension |
| Module: | mod_auth_digest |
TheAuthDigestDomain directive allows you to specify one or more URIs which are in the same protection space (i.e. use the same realm and username/password info). The specified URIs are prefixes; the client will assume that all URIs "below" these are also protected by the same username/password. The URIs may be either absolute URIs (i.e. including a scheme, host, port, etc.) or relative URIs.
This directiveshould always be specified and contain at least the (set of) root URI(s) for this space. Omitting to do so will cause the client to send the Authorization header forevery request sent to this server.
The URIs specified can also point to different servers, in which case clients (which understand this) will then share username/password info across multiple servers without prompting the user each time.
| Description: | How long the server nonce is valid |
|---|---|
| Syntax: | AuthDigestNonceLifetimeseconds |
| Default: | AuthDigestNonceLifetime 300 |
| Context: | directory, .htaccess |
| Override: | AuthConfig |
| Status: | Extension |
| Module: | mod_auth_digest |
TheAuthDigestNonceLifetime directive controls how long the server nonce is valid. When the client contacts the server using an expired nonce the server will send back a 401 withstale=true. Ifseconds is greater than 0 then it specifies the amount of time for which the nonce is valid; this should probably never be set to less than 10 seconds. Ifseconds is less than 0 then the nonce never expires.
| Description: | Sets the authentication provider(s) for this location |
|---|---|
| Syntax: | AuthDigestProviderprovider-name[provider-name] ... |
| Default: | AuthDigestProvider file |
| Context: | directory, .htaccess |
| Override: | AuthConfig |
| Status: | Extension |
| Module: | mod_auth_digest |
TheAuthDigestProvider directive sets which provider is used to authenticate the users for this location. The defaultfile provider is implemented by themod_authn_file module. Make sure that the chosen provider module is present in the server.
Seemod_authn_dbm,mod_authn_file,mod_authn_dbd andmod_authn_socache for providers.
| Description: | Determines the quality-of-protection to use in digestauthentication |
|---|---|
| Syntax: | AuthDigestQop none|auth|auth-int [auth|auth-int] |
| Default: | AuthDigestQop auth |
| Context: | directory, .htaccess |
| Override: | AuthConfig |
| Status: | Extension |
| Module: | mod_auth_digest |
TheAuthDigestQop directive determines thequality-of-protection to use.auth will only do authentication (username/password);auth-int is authentication plus integrity checking (an MD5 hash of the entity is also computed and checked);none will cause the module to use the old RFC-2069 digest algorithm (which does not include integrity checking). Bothauth andauth-int may be specified, in which the case the browser will choose which of these to use.none should only be used if the browser for some reason does not like the challenge it receives otherwise.
auth-int is not implemented yet.| Description: | The amount of shared memory to allocate for keeping trackof clients |
|---|---|
| Syntax: | AuthDigestShmemSizesize |
| Default: | AuthDigestShmemSize 1000 |
| Context: | server config |
| Status: | Extension |
| Module: | mod_auth_digest |
TheAuthDigestShmemSize directive defines the amount of shared memory, that will be allocated at the server startup for keeping track of clients. Note that the shared memory segment cannot be set less than the space that is necessary for tracking at leastone client. This value is dependent on your system. If you want to find out the exact value, you may simply setAuthDigestShmemSize to the value of0 and read the error message after trying to start the server.
Thesize is normally expressed in Bytes, but you may follow the number with aK or anM to express your value as KBytes or MBytes. For example, the following directives are all equivalent:
AuthDigestShmemSize 1048576AuthDigestShmemSize 1024KAuthDigestShmemSize 1M
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Licensed under theApache License, Version 2.0.