dacscookie(1) create DACS credentials and emit as a cookie


dacscookie [m[blue]dacsoptionsm[][1]] [-create] [-i ident] [-user user] [-ip ipaddr]
[-role role_str] [-expires date] [-ua str]
dacscookie [m[blue]dacsoptionsm[][1]] -decrypt [-concise]


This program is part of the DACS suite.

The dacscookie utility constructs DACS credentials that represent a single DACS identity and emits them as the NAME=VALUE element of a m[blue]HTTP cookiem[][2] (m[blue]RFC 2109m[][3], m[blue]RFC 2965m[][4]) that may be used by DACS. It can also decode and display these cookies, provided the same encryption keys used to create the cookies are available. The program is useful for testing purposes, or by programs that perform authentication (e.g., by calling m[blue]dacsauth(1)m[][5]) and need to return credentials. It may also be used to generate an identity "offline"; the resulting credentials could be used by applications other than standard Web browsers, or be distributed via any secure channel (e.g., encrypted email) for use by the recipient.

Configured or derived defaults are used if optional identity information is not provided.


Only the DACS administrator should be able to successfully run this program. Because DACS keys and configuration files must be limited to the administrator, this will normally be the case, but a careful administrator will set file permissions to deny access to all other users, or even delete the binary.

Similarly, access to cookies generated by this program must be carefully controlled. Any jurisdiction within the same federation in which the credentials were created will be able to directly decrypt the credentials.


dacscookie recognizes these options for cookie creation:


Create the specified credentials and emit them to the standard output as the NAME=VALUE component of an HTTP cookie. This is the default.

-expires date

Set the expiry date for the cookie. If date begins with '+' and is followed by a digit string, the expiry date will be that number of seconds relative to the current time. Otherwise, the date is expected to be in one of the recognized formats (see m[blue]concise syntaxm[][6]). If not provided, the configured default value, m[blue]AUTH_CREDENTIALS_DEFAULT_LIFETIME_SECSm[][7], will be used.

-i ident

The identity (ident) is given in the m[blue]concise syntaxm[][6]. Note that any elements that are explicitly given will override those that appear in ident.

-ip ipaddr

Use ipaddr as the user's IP address (in numerical dot notation). If not provided, this element will be obtained from any -i flag or else omitted from the credentials.

-role role_str

Use role_str as the user's role string, which must be syntactically correct. If not provided, this element will be obtained from any -i flag or else omitted from the credentials.

-ua str

Use str as the user agent string associated with the credentials. If no string is specified, the credentials cannot be verified against a user agent string. See m[blue]dacs.conf(5)m[][8].

-user name

Use name, a syntactically correct username, within the applicable jurisdiction. If not provided, this element must be specified using the -i flag.

dacscookie recognizes these options for cookie decryption:


Instead of creating credentials, read a cookie from the standard input and print its decoded contents to the standard output. If the input is invalid in any way, a message is displayed.


With the -decrypt flag, only print the identity in the m[blue]concise user syntaxm[][6].


The following will generate an identity and store it in a file:

% dacscookie -u j1.example.com -user bobo > cookie.out
% chmod 0600 cookie.out

The following will display various elements of the credentials to stdout:

% dacscookie -u j1.example.com -decrypt < cookie.out
% rm cookie.out


The program exits 0 if everything was fine, 1 if an error occurred.


Distributed Systems Software (m[blue]www.dss.cam[][14])


Copyright2003-2012 Distributed Systems Software. See the m[blue]LICENSEm[][15] file that accompanies the distribution for licensing information.