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CREDS_MSDOS(8) NetBSD System Manager's Manual CREDS_MSDOS(8)
Powered by man-cgi (2020-09-24).
Maintained for NetBSD
by Kimmo Suominen.
Based on man-cgi by Panagiotis Christias.
creds_msdos -- automatically add login credentials from MSDOS partition
The creds_msdos rc.d script allows automatic addition of login creden-
tials during boot using a special file found on the MSDOS partition of a
bootable image. This script is not distributed with the normal system
and is only included with pre-installed bootable images. The goal is to
allow remote access of the system without having to edit the primary root
file system (which may not be accessible from the host the image is being
written from), but place this information in the MSDOS partition that
most platforms can easily access.
Typically, an installable image (such as arm64.img) is written to an SD
card or similar media, and has both a native FFS partition as well as an
MSDOS partition for booting. If this script is enabled and has been
pointed at the boot partition it will inspect the file creds.txt for any
credentials to be added to the system.
These are the supported options in the credentials files:
sshkeyfile user keyfile
sshkey user keystring
useraddpwhash user pwhash
useradd user password
In all cases user is the username to be added, and the user will be added
to the ``wheel'' group.
The sshkeyfile method looks in the MSDOS boot partition for the specified
file and merges ssh keys from this file into user's
The sshkey method adds the keystring to the user's ~/.ssh/authorized_keys
The useraddpwhash method uses pwhash as the users's password hash.
The above three methods are the preferred methods.
For the useradd method password is an unencrypted raw password that will
be hashed and added to the system. This method is not recommended as it
leaves unencrypted passwords around until such time that the script runs.
If this method is used then the creds.txt file will be shredded and
deleted using ``rm -P'' after the credentials are updated.
pwhash(1), rm(1), ssh(1), ssh_config(5), mount_msdos(8), sshd(8),
The creds_msdos script appeared in NetBSD 9.0.
Matthew R. Green <firstname.lastname@example.org>.
NetBSD 9.99 June 10, 2019 NetBSD 9.99