Class BasicAuthHandler
- All Implemented Interfaces:
Handler
BasicAuthHandler
obtains a Session ID by performing
"basic" authentication, using either the "Authorization" or the
"Proxy-Authorization" headers. This handler prevents
subsequent downstream handlers from being accessed unless the proper
authentication was seen in the request. The Session ID obtained by this
handler is meant to be used by those downsteams handlers to access
whatever session-dependent information they need.
If the request does not contain the authentication headers or the
authentication information is not valid, this handler sends an HTTP
error message along with the "WWW-Authenticate" or "Proxy-Authenticate"
header, as appropriate. See
code
,
authorization
,
authenticate
If the request does contain valid authentication information, the
Session ID associated with the authentication information is inserted
into the request properties, for use by downstream handlers. After
inserting the Session ID, this handler returns false
to
allow the downstream handlers to run.
IF the Session ID in empty (e.g. ""), then, although authenticateion
succeeds, no Session Id property is set.
The set of valid Session IDs is contained
in a globally accessible table managed by the SessionManager
,
which may be initialized with a static table
(see mapFile
).
The format of the initialization table (if any) described above is a Java properties file where keys are the Base64 encoded strings obtained from the Authentication header and the values are the associated Session IDs. Base64 strings can contain the '=' character, but the keys in a Java properties file cannot contain an '=' character, so all '=' characters in the Base64 strings must be converted to '!' in the properties file, as shown in the following sample properties file:
bXIuIGhhdGU6a2ZqYw!! = radion Zm9vOmJhcg!! = fooThe data in the SessionManager table doesn't use the '!'s, only ='s.
There are several different types of authentication possible. All authentication handlers should follow these basic principles:
- The authentication handler examines some aspect of the request to decide if the appropriate authentication is present.
- If the request is acceptable, the authentication handler should
insert the extracted Session ID into a request property
and then return
false
, to allow subsequent handlers to run and perhaps use the Session ID. - If the request is not acceptable, the authentication handler can return an error message or do some other thing to try to obtain a valid authentication.
- Handlers wishing to be protected by authentication should not subclass an authentication handler. Instead, such handler should be written to assume that authentication has already been performed and then just examine the Session ID present. The web developer is then responsible for choosing which one (of possibly many) forms of authentication to use and installing those authentication handlers before the "sensitive" handler.
- Handlers that are protected by an authentication handler can use the Session ID stored in the request properties regardless of the specifics of the authentication handler.
handlers=auth history file auth.class=BasicAuthHandler auth.session=account auth.message=Go away, you're not allowed here! history.class=HistoryHandler history.session=account file.class=FileHandler file.root=htdocsIn the sample pseudo-configuation file specified above, the
BasicAuthHandler
is first invoked to see if the HTTP "basic"
authentication header is present in the request. If it isn't, a nasty
message is sent back. If the "basic" authentication header is present
and corresponds to a user that the BasicAuthHandler
knows
about, the Session ID associated with that user is stored in the specified
property named "account".
Subsequently, the HistoryHandler
examines its specified
property (also "account") for the Session ID and uses that to keep
track of which session is issuing the HTTP request.
Each handler that needs a Session ID should have a configuration parameter that allows the web developer to specify the name of the request property that holds the Session ID. Multiple handlers can all use the same request property as each other, all protected by the same authentication handler.
This handler uses the following configuration properties:
- prefix, suffix, glob, match
- Sepcify the URL that triggers this handler.
-
code
- The type of authentication to perform. The default value is 401.
The value 401 corresponds to standard "basic" authentication. The "Authorization" request header is supposed to contain the authentication string. If the request was not authenticated, the "WWW-Authenticate" header is sent in the HTTP error response to cause the browser to prompt the client to authenticate.
The value 407 corresponds to "basic" proxy/firewall authentication. The "Proxy-Authorization" request header is supposed to contain the authentication string. If the request was not authenticated, the "Proxy-Authenticate" header is sent in the HTTP error response to cause the browser to prompt the client to authenticate.
Any other value may also be specified. Whatever the value, it will be returned as the HTTP result code of the error message.
-
authorization
- If specified, this is the request header that will contain the
"basic" authentication string, instead of the "Authorization"
or "Proxy-Authorization" header implied by
code
. -
authenticate
- If specified, this is the response header that will be sent in the
HTTP error response if the user is not authenticated.
If this string is "", then this handler will authenticate the request if the authorization header is present, but will not send an HTTP error message if the request could not be authenticated. This is useful if the web developer wants to do something more complex (such as invoking an arbitrary set of handlers) instead of just sending a simple error message if the request was not authenticated. In this case, the web developer can determine that the request was not authenticated because no Session ID will be present in the request properties.
-
realm
- The "realm" of the HTTP authentication error message. This is a string that the browser is supposed to present to the client when asking the client the authenticate. It provides a human-friendly name describing who wants the authentication.
-
message
- The body of the HTTP authentication error message. This will be
displayed by the browser if the client chooses not to authenticate.
The default value is "". Patterns of the form ${xxx} are
replaced with the value of the xxx
entry of
request.props
. -
mapFile
- If specified, this is the initial Session ID file.
This is expected to be
a java properties file, whose keys are the authentication tokens,
and whose values are the Session IDs that are inserted into the
request properties.
The keys in the file are basic authentication (base64) tokens with any trailing
"="
characters changed to"!"
. -
session
- The name of the request property that the Session ID will be stored in, to be passed to downstream handlers. The default value is "SessionID".
-
ident
- The
ident
argument toSessionManager.getSession(java.lang.Object, java.lang.Object, java.lang.Class)
to get the table of valid sessions. The default value is "authorized". Ifident
is of the formident:session
, then thesession
portion is used as thesession
argument to SessionManager.get(). Otherwise thesession
argument is NULL. This table may be manipulated with the SetTemplate, using the "ident" namespace and "session" for the SetTemplate "sessionTable" parameter.
- Version:
- 2.3, 06/11/13
- Author:
- Stephen Uhler (stephen.uhler@sun.com), Colin Stevens (colin.stevens@sun.com)
-
Field Summary
Fields -
Constructor Summary
Constructors -
Method Summary
-
Field Details
-
code
public int code -
authorization
-
authenticate
-
realm
-
message
-
mapFile
-
session
-
ident
-
sessionTable
-
-
Constructor Details
-
BasicAuthHandler
public BasicAuthHandler()
-
-
Method Details
-
init
Initializes this handler. It is an error if themapFile
parameter is specified but that file cannot be loaded. -
respond
Looks up the credentials for this request, and insert them into the request stream. If no credentials are found, prompt the user for them.- Specified by:
respond
in interfaceHandler
- Parameters:
request
- TheRequest
object that represents the HTTP request.- Returns:
true
if the request was handled. A request was handled if a response was supplied to the client, typically by callingRequest.sendResponse()
orRequest.sendError
.- Throws:
IOException
- if there was an I/O error while sending the response to the client. Typically, in that case, theServer
will (try to) send an error message to the client and then close the client's connection.The
IOException
should not be used to silently ignore problems such as being unable to access some server-side resource (for example getting aFileNotFoundException
due to not being able to open a file). In that case, theHandler
's duty is to turn thatIOException
into a HTTP response indicating, in this case, that a file could not be found.
-
complain
Authentication failed. Send the appropriate authentication required header as a response.- Parameters:
request
- The request to respond toreason
- The reason for failure (for diagnostics)- Returns:
- True
- Throws:
IOException
-