KEYSRV(4) KEYSRV(4)
NAME
keysrv - secret key server
SYNOPSIS
auth/keysrv
DESCRIPTION
Keysrv is a file service run on a connection to an authenti-
cation server. It allows a remote user to change a secret
stored on the server by keyfs(4), which must have been
started before keysrv, in a name space with the authentica-
tion data available under /mnt/keys.
Keysrv serves a single file, secret, on a connection
accessed through file descriptor 0 (ie, the standard
`input'). When invoked, it first authenticates the connec-
tion using security-auth(2), requiring the client to use
sha1 and rc4_256. If authentication succeeds, keysrv
exports a name space containing a file secret. The authen-
tication ensures that only a user that possesses a valid
certificate can connect to the service.
If the authenticated user (ie, the user name in the verified
certificate) has an entry in /mnt/keys, as served by
keyfs(4), and that user has a non-empty secret, then the
file secret will accept reads and writes. (Otherwise, every
read or write returns an appropriate error.) Every success-
ful read returns 0 bytes; thus a read can be used to check
that the user is known and has a secret key. Each write
contains data of the following form:
oldhash [ newsecret ]
Oldhash is the SHA1 hash (see keyring-sha1(2)) of the user's
existing secret, as 20 hexadecimal digits. If the value of
oldhash does not match that of the stored secret, the write
returns an error and suitable diagnostic. Oldhash is
optionally followed by a newsecret, in clear text as a
sequence of bytes (typically the secret as utf(6)), sepa-
rated from oldhash by a single space. If the oldhash
matches that of the secret currently stored, newsecret
replaces it. The write returns an error if oldhash does not
match the stored value, or if something else goes wrong.
Keysrv can be invoked via listen(1):
listen -t -A 'tcp!*!infkey' {auth/keysrv}
Normally that is done automatically when starting an authen-
tication service using svc/auth (see svc(8)).
Page 1 Plan 9 (printed 11/22/24)
KEYSRV(4) KEYSRV(4)
Passwd(1) dials the service, authenticates, and mounts the
resulting connection on /mnt/keysrv, where it accesses the
secret file to change the secret.
FILES
/mnt/keys mount point for keyfs(4)
/mnt/keysrv exported mount point for keysrv
SOURCE
/appl/cmd/auth/keysrv.b
SEE ALSO
listen(1), passwd(1), keyfs(4), logind(8)
Page 2 Plan 9 (printed 11/22/24)