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><A
NAME="CHKPASS"
>F.6. chkpass</A
></H1
><P
> This module implements a data type <TT
CLASS="TYPE"
>chkpass</TT
> that is
designed for storing encrypted passwords.
Each password is automatically converted to encrypted form upon entry,
and is always stored encrypted. To compare, simply compare against a clear
text password and the comparison function will encrypt it before comparing.
</P
><P
> There are provisions in the code to report an error if the password is
determined to be easily crackable. However, this is currently just
a stub that does nothing.
</P
><P
> If you precede an input string with a colon, it is assumed to be an
already-encrypted password, and is stored without further encryption.
This allows entry of previously-encrypted passwords.
</P
><P
> On output, a colon is prepended. This makes it possible to dump and reload
passwords without re-encrypting them. If you want the encrypted password
without the colon then use the <CODE
CLASS="FUNCTION"
>raw()</CODE
> function.
This allows you to use the
type with things like Apache's <TT
CLASS="LITERAL"
>Auth_PostgreSQL</TT
> module.
</P
><P
> The encryption uses the standard Unix function <CODE
CLASS="FUNCTION"
>crypt()</CODE
>,
and so it suffers
from all the usual limitations of that function; notably that only the
first eight characters of a password are considered.
</P
><P
> Note that the <TT
CLASS="TYPE"
>chkpass</TT
> data type is not indexable.
</P
><P
> Sample usage:
</P
><PRE
CLASS="PROGRAMLISTING"
>test=# create table test (p chkpass);
CREATE TABLE
test=# insert into test values ('hello');
INSERT 0 1
test=# select * from test;
p
----------------
:dVGkpXdOrE3ko
(1 row)
test=# select raw(p) from test;
raw
---------------
dVGkpXdOrE3ko
(1 row)
test=# select p = 'hello' from test;
?column?
----------
t
(1 row)
test=# select p = 'goodbye' from test;
?column?
----------
f
(1 row)</PRE
><DIV
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><H2
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><A
NAME="AEN146752"
>F.6.1. Author</A
></H2
><P
> D'Arcy J.M. Cain (<CODE
CLASS="EMAIL"
><<A
HREF="mailto:darcy@druid.net"
>darcy@druid.net</A
>></CODE
>)
</P
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