mod_auth_tkt(3) User Contributed Perl Documentation mod_auth_tkt(3)NAMEmod_auth_tkt - apache ticket authentication module
DESCRIPTIONmod_auth_tkt is a lightweight cookie-based authentication module,
written in C, for apache versions 1.3.x, 2.0.x, and 2.2.x It implements
a single-signon framework that works across multiple apache instances,
different apache versions, and multiple machines.
mod_auth_tkt itself is completely repository-agnostic, as the actual
authentication is done by a user-supplied CGI or script in your
language of choice (examples are provided in Perl, with contrib
libraries for use with python and PHP). This allows authentication
against virtually any kind of user repository you can imagine (password
files, ldap directories, databases, etc.)
mod_auth_tkt supports inactivity timeouts (including the ability to
control how aggressively the ticket is refreshed), the ability to
include arbitrary user data within the cookie, configurable cookie
names and domains, token-based access to subsections of a site, and
optional 'guest' access for unauthenticated users.
CONFIGURATIONmod_auth_tkt is configured in your apache configuration files using the
following set of directives (all mod_auth_tkt directives begin with
'TKTAuth'):
Server Directives
mod_auth_tkt supports two apache server-level directives, one required
- TKTAuthDigest, the shared secret used for digest hashing - and one
optional - TKTAuthDigestType, the type of digest to use in ticket
hashes. Both may be global or specific to a virtual host.
TKTAuthSecret <secret>
String - the secret used for digest hashing. This should be kept
secret and changed periodically. e.g.
TKTAuthSecret "w b@5b15#664038f.f9d8U19b7e25 664eY9ad2%4393e,a2ef"
TKTAuthDigestType [ MD5 | SHA256 | SHA512 ]
String, one of MD5 | SHA256 | SHA512. The digest/hash type to use
in tickets. The default is MD5, which is faster, but has now been
shown to be vulnerable to collision attacks. Such attacks are not
directly applicable to mod_auth_tkt, which primarily relies on the
security of the shared secret rather than the strength of the
hashing scheme. More paranoid users will probably prefer to use one
of the SHA digest types, however.
The default is likely to change in a future version, so setting the
digest type explicitly is encouraged.
Note that using one of the SHA digest types with the perl CGI
scripts requires a version of Apache::AuthTkt >= 2.1.
Directory Directives
All directory-level directives are optional, except that either
TKTAuthLoginURL or TKTAuthGuestLogin (or both) must be set to cause
mod_auth_tkt to be invoked for a particular directory. As usual,
directory-level directives may be set in Directory or Location
sections, or in .htaccess files.
AuthType None / require <users>
mod_auth_tkt requires the following standard apache authentication
directives to trigger authentication:
AuthType None
require valid-user # or require user1, user2, etc.
TKTAuthLoginURL <url>
Standard URL to which unauthenticated users are redirected. This
is a required directive unless you are using guest mode via
'TKTAuthGuestLogin on'. e.g.
TKTAuthLoginURL https://www.example.com/auth/login.cgi
TKTAuthTimeoutURL <url>
URL to which users are redirected in the event their ticket times
out. Default: TKTAuthLoginURL. e.g.
TKTAuthTimeoutURL https://www.example.com/auth/login.cgi?timeout=1
TKTAuthPostTimeoutURL <url>
URL to which users are redirected in the event their ticket times
out during a POST operation. This case is distinguished to allow
you to handle such cases specially - you probably don't want to
redirect back to the referrer after login, for instance. Default:
TKTAuthTImeoutURL. e.g.
TKTAuthPostTimeoutURL https://www.example.com/auth/login.cgi?posttimeout=1
TKTAuthUnauthURL <url>
URL to which users are redirected in the event that they are not
authorised for a particular area e.g. incorrect tokens.
TKTAuthUnauthURL https://www.example.com/auth/login.cgi?unauth=1
TKTAuthGuestLogin <boolean>
Flag to turn on 'guest' mode, which means that any user without a
valid ticket is authenticated anyway as the TKTAuthGuestUser user.
This is useful for allowing public access for guests and robots,
while allowing more personalised or privileged access for users who
login. Default: off. e.g.
TKTAuthGuestLogin on
TKTAuthGuestCookie <boolean>
Flag to indicate whether or not to issue a ticket cookie for guest
users. Issuing a cookie is primarily useful where you are using
UUID-ed guest users where you want them to keep the initial guest
username you issue them for tracking purposes. e.g.
TKTAuthGuestCookie on
Default is 'off', unless you use a TKTAuthGuestUser with a UUID
(see next), in which case it's 'on'. Setting explicitly is
recommended, however.
TKTAuthGuestUser <string>
Username to be used for the guest user (in the ticket uid,
REMOTE_USER environment variable, etc).
On apache 2.0.x and 2.2.x (but not on apache 1.3.x), the
TKTAuthGuestUser may also contain a special sprintf-like pattern
'%U', which is expanded to 36-character UUID, allowing
individualised guest usernames. The %U may also include an integer
<= 36 to limit the number of characters used in the UUID e.g. %12U,
%20U etc.
Default: 'guest'. Examples:
TKTAuthGuestUser visitor
TKTAuthGuestUser guest-%12U
TKTAuthGuestFallback <boolean>
Flag to indicate that a timed out user ticket should automatically
fallback to 'guest' status, and issue a new guest ticket, instead
of redirecting to the TKTAuthTimeoutURL. Only makes sense with
TKTAuthGuestLogin on, of course.
Default: off.
TKTAuthTimeout <seconds>
The ticket timeout period, in seconds. After this period, the
ticket is considered stale, and the user is redirected to the
TKTAuthTimeoutURL (if set, else to the TKTAuthLoginURL). Note that
the ticket can be automatically refreshed, however, using the next
setting.
The following units can also be specified on the timeout (with no
spaces between timeout and unit): y/years, M/months, w/weeks,
d/days, h/hours, m/minutes, and s/seconds.
This timeout is protected by the ticket hashing, so cannot be
trivially modified, unlike the TKTAuthCookieExpires setting below.
Setting TKTAuthTimeout to 0 means never timeout, but this is
strongly discouraged, as it allows for trivial replay attacks. Set
it to a week or two if you really don't want timeouts.
Default: 2h. Examples:
TKTAuthTimeout 86400
TKTAuthTimeout 1w
TKTAuthTimeout 1w 4d 3h
TKTAuthTimeoutRefresh <decimal>
A number between 0 and 1 indicating whether and how to refresh
ticket timestamps. 0 means never refresh (hard timeouts). 1 means
refresh tickets every time. .33 (for example) means refresh if less
than .33 of the timeout period remains.
This is a politeness setting for those paranoid types who have
their browsers set to confirm all cookies - refreshing every time
quickly becomes VERY tedious. Default: 0.5. e.g.
TKTAuthTimeoutRefresh 0.66
TKTAuthCookieName <name>
The name used for the ticket cookie. Default: 'auth_tkt'.
TKTAuthDomain <domain>
The domain to use in ticket cookies, which defines the hosts for
which the browser will submit this cookie. Default: the apache
ServerName (either global or for a specific virtual host).
TKTAuthCookieExpires <seconds>
NB: This directive is not currently supported on apache 1.3.x!
The period until the cookie expires, used to set the 'expires'
field on the ticket cookie, in seconds. This is useful if you want
cookies to persist across browser sessions (and your login script
must support it too, of course).
The following units can also be specified on the expiry period
(with no spaces between period and unit): y/years, M/months,
w/weeks, d/days, h/hours, m/minutes, and s/seconds.
Note that his is a client-side setting and is not protected by the
ticket hashing, so you should always set a TKTAuthTimeout in
addition to using an expiry. Cookie expiries are refreshed with
tickets if TKTAuthTimeoutRefresh is set.
Default: none (not used).
e.g.
TKTAuthCookieExpires 86400
TKTAuthCookieExpires 1w
TKTAuthCookieExpires 1w 3d 4h
TKTAuthBackArgName <name>
The name used for the back GET parameter. If this is set,
mod_auth_tkt will add a GET parameter to all redirect URLs
containing a URI-escaped version of the current requested page e.g.
if the requested page is http://www.example.com/index.html and
TKTAuthBackArgName is set to 'back', mod_auth_tkt will add a
parameter like:
back=http%3A%2F%2Fwww.example.com%2Findex.html
to the TKTAuthLoginURL it redirects to, allowing your login script
to redirect back to the requested page upon successful login.
To omit altogether, set to the string None i.e.
TKTAuthBackArgName None
Default: 'back'.
TKTAuthBackCookieName <name>
The cookie name to use for the back cookie. If this is set,
mod_auth_tkt will set a back cookie containing a URI-escaped
version of current requested page when redirecting (see
TKTAuthBackArgName above), instead of using a GET parameter.
Default: none (not used).
TKTAuthToken <token>
String indicating a required token for the given location,
implementing a simple form of token-based access control. If the
user's ticket does not contain one or more of the required tokens
in the ticket token list then mod_auth_tkt will redirect to the
TKTAuthUnauthURL location (or TKTAuthLoginURL if not set). Your
login script is expected to set the appropriate token list up at
login time, of course.
Note that this directive can be repeated, and the semantics are
that any of the required tokens is sufficient for access i.e. the
tokens are ORed.
Default: none (not used).
e.g.
TKTAuthToken finance
TKTAuthToken admin
TKTAuthIgnoreIP <boolean>
Flag indicating that mod_auth_tkt should ignore the client IP
address in authenticating tickets (your login script must support
this as well, setting the client IP address to 0.0.0.0). This is
often required out on the open internet, especially if you are
using an HTTPS login page (as you should) and are dealing with more
than a handful of users (the typical problem being transparent HTTP
proxies at ISPs).
Default: 'off' i.e. ticket is only valid from the originating IP
address.
e.g.
TKTAuthIgnoreIP on
TKTAuthRequireSSL <boolean>
Flag used to indicate that tickets should be refused except in
SSL/HTTPS protected contexts (redirects to TKTAuthLoginURL if not,
which presumably would be using HTTPS). Default: 'off' (don't
require SSL). e.g.
TKTAuthRequireSSL on
See also TKTAuthCookieSecure below.
TKTAuthCookieSecure <boolean>
Flag used to set the 'secure' flag on all ticket cookies issued,
indicating to the browser that they should only be sent in
SSL/HTTPS protected contexts. Default: 'off' (don't set 'secure'
flag). e.g.
TKTAuthCookieSecure on
TKTAuthRequireSSL and TKTAuthCookieSecure are normally used
together. One case where it makes sense to use them separately is
where you are proxying through a separate SSL-equipped reverse
proxy, where you would want to use TKTAuthCookieSecure by itself
(since the proxied request will never be via SSL).
TKTAuthDebug <integer>
Turn on mod_auth_tkt debug output messages in your error log, with
verbosity increasing with higher integer values. Current range:
1-3.
Note that you will also require apache 'LogLevel debug' set to see
these messages.
EXAMPLES
Minimal config using logins:
<Location /secret1>
AuthType None
require valid-user
TKTAuthLoginURL https://www.example.com/auth/login.cgi
</Location>
Minimal config using guest logins (users can still login explicitly, of
course):
<Location /secret2>
AuthType None
require valid-user
TKTAuthGuestLogin on
</Location>
Example internet configuration:
<Location /secret3>
AuthType None
require valid-user
TKTAuthLoginURL https://www.example.com/auth/login.cgi
TKTAuthTimeoutURL https://www.example.com/auth/login.cgi?timeout=1
TKTAuthPostTimeoutURL https://www.example.com/auth/login.cgi?timeout=1&post=1
TKTAuthIgnoreIP on
TKTAuthTimeout 2h
TKTAuthCookieExpires 2h
</Location>
Example intranet configuration:
<Location /secret4>
AuthType None
require valid-user
TKTAuthGuestLogin on
TKTAuthLoginURL https://www.example.com/auth/login.cgi
TKTAuthTimeoutURL https://www.example.com/auth/login.cgi?timeout=1
TKTAuthPostTimeoutURL https://www.example.com/auth/login.cgi?timeout=1&post=1
TKTAuthTimeout 4h
TKTAuthCookieExpires 4h
</Location>
SUPPORT
Support is available on the mod_auth_tkt mailing list, courtesy of
sourceforge:
List
modauthtkt-users@lists.sourceforge.net
List Page and Signup
https://lists.sourceforge.net/lists/listinfo/modauthtkt-users
List Archive
http://sourceforge.net/mailarchive/forum.php?forum=modauthtkt-users
BUGS
Ticket payload should include IP address, to make debugging IP address
problems easier.
AUTHOR
Gavin Carr <gavin@openfusion.com.au>
LICENCEmod_auth_tkt is licensed under the terms of the Apache Licence.
2.1.0 2016-02-19 mod_auth_tkt(3)
