Provided by: dacs_1.4.28b-3ubuntu1_amd64 
NAME
dacs_passwd - manage private DACS passwords
SYNOPSIS
dacs_passwd [dacsoptions[1]]
DESCRIPTION
This program is part of the DACS suite.
The dacs_passwd web service is used to manage usernames and passwords recognized by
local_passwd_authenticate[2], a DACS authentication module. This utility serves a similar
purpose for local_passwd_authenticate that Apache's htpasswd(1)[3] command does for its
mod_auth[4] and mod_auth_dbm[5] modules. These accounts and passwords are used only by
local_passwd_authenticate and are completely separate from any other accounts and
passwords.
Note
Much of the functionality of this program is also available as a DACS utility,
dacspasswd(1)[6], which operates on the same password files. Because dacs_admin(8)[7]
provides the same functionality and more, dacs_passwd may be removed in a future
release.
Security
The default DACS ACL restricts use of this web service to a DACS administrator and to
users who are setting the password for their own DACS account at the receiving
jurisdiction. Administrators should ensure that the ACL for dacs_passwd is correct for
their environment.
OPTIONS
Web Service Arguments
In addition to the standard CGI arguments[8], dacs_passwd understands the following CGI
arguments:
OPERATION
The following operations are supported:
• ADD
Like SET but add or replace an entry for USERNAME.
• DELETE
Delete the account for USERNAME.
• DISABLE
Disable the account for USERNAME.
• ENABLE
Enable the account for USERNAME.
• LIST
List USERNAME, if it exists, otherwise all usernames. A disabled account is
indicated by a '*' (which is not a valid character in a username).
• SET
Sets or resets a DACS password for USERNAME to NEW_PASSWORD. The
CONFIRM_NEW_PASSWORD argument must also be given and be identical to NEW_PASSWORD.
Unless the operation is performed by a DACS administrator (i.e., an
ADMIN_IDENTITY[9]) or disabled by the PASSWORD_OPS_NEED_PASSWORD[10] directive,
the current password for USERNAME must be given as PASSWORD.
Security
For users other than a DACS administrator, a password must meet certain
requirements on its length and the character set from which it is comprised.
Note that these requirements are only significant at the time a password is
set or changed; existing passwords are unaffected by changes to the
configuration directives. Please refer to the PASSWORD_CONSTRAINTS[11]
directive.
Users should be made aware of security issues related to passwords, including
better techniques for selecting passwords and keeping them private.
How to choose better passwords
Users might consider adopting a method such as the one described in this
proposal[12]. It suggests that users construct site-specific passwords from
three components:
1. PIN-1, a short, random string that is common to all of the user's
passwords, kept secret, and not likely to be in any dictionary;
2. SITE, a string that is derived from the site's domain name using some
simple and easy-to-remember procedure (e.g., using the first four letters
or consonents); and
3. PIN-2, a short, site-specific random string (this component is different
for each of a user's passwords, and is something not likely to be in any
dictionary).
PIN-1 is memorized by the user. The other two components may be written down
but must be kept in a relatively secure location (such as in the user's wallet
or in a desk drawer). The user forms his or her passwords by combining these
three components in any order that is easy to remember.
For the site www.example.net, a user might select the password "examRB8s#i8",
where "exam" (component 2, SITE) is derived from the site's domain name,
"RB8s" is a random string used with this password only (component 3, PIN-2),
and "#i8" is the user's secret PIN (component 1, PIN-1). Because it is
probably difficult to remember, the user might create a note with "examRB8s"
written on it (SITE and PIN-2), but not PIN-1.
For the site dacs.dss.ca, the same user might select the password
"dssceIM#i8".
Since most people are not very good at it, the random strings should be chosen
using a good-quality random generator, such as the random()[13] function:
% dacsexpr -e "random(string, 4, 'a-zA-Z0-9,./;@#')"
"y2FJ"
In addition to being difficult to guess because of their random components and
reasonably large character set, these passwords are different for each site;
should one password be compromised, the others are not immediately available
to an attacker. Similarly, the written strings cannot be immediately exploited
if they are stolen or copied. The strength of the method can be increased by
making either or both PIN components longer, or chosen from a larger space of
characters.
ACCOUNT
Either PASSWD (the default) or SIMPLE, case insensitively, to select between the item
types passwds and simple, respectively. The requested item type must be configured
(see dacs.conf(5)[14]).
USERNAME
The DACS username of interest.
FORMAT
By default, output is emitted in HTML. Several varieties of XML output can be
selected, however, using the FORMAT argument (please refer to dacs(1)[15] and
dacs_passwd.dtd[16]).
DIAGNOSTICS
The program exits 0 if everything was fine, 1 if an error occurred.
SEE ALSO
dacspasswd(1)[6], dacs.conf(5)[17]
AUTHOR
Distributed Systems Software (www.dss.ca[18])
COPYING
Copyright2003-2013 Distributed Systems Software. See the LICENSE[19] file that accompanies
the distribution for licensing information.
NOTES
1. dacsoptions
http://dacs.dss.ca/man/dacs.1.html#dacsoptions
2. local_passwd_authenticate
http://dacs.dss.ca/man/dacs_authenticate.8.html#local_passwd_authenticate
3. htpasswd(1)
http://httpd.apache.org/docs/2.2/programs/htpasswd.html
4. mod_auth
http://httpd.apache.org/docs-2.2/mod/mod_auth.html
5. mod_auth_dbm
http://httpd.apache.org/docs-2.2/mod/mod_auth_dbm.html
6. dacspasswd(1)
http://dacs.dss.ca/man/dacspasswd.1.html
7. dacs_admin(8)
http://dacs.dss.ca/man/dacs_admin.8.html
8. standard CGI arguments
http://dacs.dss.ca/man/dacs.services.8.html#standard_cgi_args
9. ADMIN_IDENTITY
http://dacs.dss.ca/man/dacs.conf.5.html#ADMIN_IDENTITY
10. PASSWORD_OPS_NEED_PASSWORD
http://dacs.dss.ca/man/dacs.conf.5.html#PASSWORD_OPS_NEED_PASSWORD
11. PASSWORD_CONSTRAINTS
http://dacs.dss.ca/man/dacs.conf.5.html#PASSWORD_CONSTRAINTS
12. this proposal
http://www.f-secure.com/weblog/archives/00001691.html
13. random()
http://dacs.dss.ca/man/dacs.exprs.5.html#random
14. dacs.conf(5)
http://dacs.dss.ca/man/dacs.conf.5.html#VFS
15. dacs(1)
http://dacs.dss.ca/man/dacs.1.html
16. dacs_passwd.dtd
http://dacs.dss.ca/man/../dtd-xsd/dacs_passwd.dtd
17. dacs.conf(5)
http://dacs.dss.ca/man/dacs.conf.5.html
18. www.dss.ca
http://www.dss.ca
19. LICENSE
http://dacs.dss.ca/man/../misc/LICENSE