KEYFS(4) KEYFS(4)
NAME
keyfs - authentication database files
SYNOPSIS
keyfs [ -mmntpt ] [ -kkey ] [ -rnsfile ] [ keyfile ]
DESCRIPTION
Keyfs serves a two-level file tree for manipulating authen-
tication information. It runs on the machine providing
authentication service for the local Plan 9 network, which
may be a dedicated authentication server or a CPU server.
The programs described in auth(8) use keyfs as their inter-
face to the authentication database.
Keyfs reads and decrypts file keyfile (default /adm/keys)
using the DES key key, which is by default read from
#r/nvram (see rtc(3)). Keyfile holds a 41-byte record for
each user in the database. Each record is encrypted sepa-
rately and contains the user's name, DES key, status, host
status, and expiration date. The name is a null-terminated
UTF string NAMELEN bytes long. The status is a byte con-
taining binary 0 if the account is enabled, 1 if it is dis-
abled. Host status is a byte containing binary 1 if the
user is a host, and 0 otherwise. The expiration date is
four-byte little-endian integer which represents the time in
seconds since the epoch (see date(1)) at which the account
will expire. If any changes are made to the database that
affect the information stored in keyfile, a new version of
the file is written. If given option -r, keyfs rebuilds its
name space from nsfile before writing any changes to its
database.
There are two authentication databases, one for Plan 9 user
information, and one for SecureNet user information. A user
need not be installed in both databases but must be
installed in the Plan 9 database to connect to a Plan 9
server.
Keyfs serves an interpretation of the keyfile in the file
tree rooted at mntpt (default /mnt/keys). Each user user in
keyfile is represented as the directory mntpt/user.
Making a new directory in mntpt creates a new user entry in
the database. Removing a directory removes the user entry,
and renaming it changes the name in the entry. Keyfs does
not allow duplicate names when creating or renaming user
entries.
All files in the user directories except for key contain UTF
strings with a trailing newline when read, and should be
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KEYFS(4) KEYFS(4)
written as UTF strings with or without a trailing newline.
Key contains the DESKEYLEN-byte encryption key for the user.
The following files appear in the user directories.
key The authentication key for the user. If the user's
account is disabled or expired, reading this file
returns an error. Writing key changes the key in the
database.
log The number of consecutive failed authentication
attempts for the user. Writing the string bad incre-
ments this number; writing good resets it to 0. If the
number reaches fifty, keyfs disables the account. Once
the account is disabled, the only way to enable it is
to write the string ok to status. This number is not
stored in keyfile, and is initialized to 0 when keyfs
starts.
status
The current status of the account, either ok or
disabled. Writing ok enables the account; writing
disabled disables it.
expire
The expiration time for the account. When read, it
contains either the string never or the time in seconds
since the epoch that the account will expire. When
written with strings of the same form, it sets the
expiration date for the user. If the expiration date
is reached, the account is not disabled, but key cannot
be read without an error.
ishost
This file exists only if the user is a host (the host
status for the user is 1). Hosts are the only users
able to receive calls. Creating it makes the user a
host and sets the host status to 1, and removing it
sets the host status to 0.
FILES
/adm/keys
Encrypted key file for the Plan 9 database.
/adm/netkeys
Encrypted key file for the SecureNet database.
#r/nvram
The non-volatile RAM on the server, which holds the
key used to decrypt key files.
SEE ALSO
auth(6), namespace(6), auth(8)
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