xref: /freebsd/stand/forth/check-password.4th.8 (revision cc68614da8232d8baaca0ae0d0dd8f890f06623e)
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25.\" $FreeBSD$
26.\"
27.Dd June 24, 2018
28.Dt CHECK-PASSWORD.4TH 8
29.Os
30.Sh NAME
31.Nm check-password.4th
32.Nd FreeBSD password-checking boot module
33.Sh DESCRIPTION
34The file that goes by the name of
35.Nm
36is a set of commands designed to do one or more of the following:
37.Pp
38.Dl o Prevent booting without password
39.Dl o Prevent modification of boot options without password
40.Dl o Provide a password to mount geli(8) encrypted root disk(s)
41.Pp
42The commands of
43.Nm
44by themselves are not enough for most uses.
45Please refer to the
46examples below for the most common situations, and to
47.Xr loader 8
48for additional commands.
49.Pp
50Before using any of the commands provided in
51.Nm ,
52it must be included
53through the command:
54.Pp
55.Dl include check-password.4th
56.Pp
57This line is present in
58.Pa /boot/loader.4th
59file, so it is not needed (and should not be re-issued) in a normal setup.
60.Pp
61The commands provided by it are:
62.Pp
63.Bl -tag -width disable-module_module -compact -offset indent
64.It Ic check-password
65Multi-purpose function that can protect the interactive boot menu,
66prevent boot without password, or prompt for geli(8) passphrase
67.Pq depending on Xr loader.conf 5 settings .
68.Pp
69First checks
70.Va bootlock_password
71and if-set, the user cannot continue until the correct password is entered.
72.Pp
73Next, checks
74.Va geom_eli_passphrase_prompt
75and if set to
76.Li YES
77.Pq case-insensitive
78prompts the user to enter their GELI password for later mounting of the root
79device(s) during boot.
80.Pp
81Last, checks
82.Va password
83and if-set, tries to
84.Ic autoboot
85and only prompts for password on failure or user-interrupt.
86See
87.Xr loader.conf 5
88for additional information.
89.El
90.Pp
91The environment variables that effect its behavior are:
92.Bl -tag -width bootlock_password -offset indent
93.It Va bootlock_password
94Sets the bootlock password (up to 255 characters long) that is required by
95.Ic check-password
96to be entered before the system is allowed to boot.
97.It Va geom_eli_passphrase_prompt
98Selects whether loader(8) will prompt for GELI credentials, handing-off to the
99kernel for later mounting of
100.Xr geli 8
101encrypted root device(s).
102.It Va password
103Sets the password (up to 255 characters long) that is required by
104.Ic check-password
105before the user is allowed to visit the boot menu.
106.El
107.Sh FILES
108.Bl -tag -width /boot/check-password.4th -compact
109.It Pa /boot/loader
110The
111.Xr loader 8 .
112.It Pa /boot/check-password.4th
113.Nm
114itself.
115.It Pa /boot/loader.rc
116.Xr loader 8
117bootstrapping script.
118.El
119.Sh EXAMPLES
120Standard i386
121.Pa /boot/loader.rc :
122.Pp
123.Bd -literal -offset indent -compact
124include /boot/loader.4th
125check-password
126.Ed
127.Pp
128Set a password in
129.Xr loader.conf 5
130to prevent modification of boot options:
131.Pp
132.Bd -literal -offset indent -compact
133password="abc123"
134.Ed
135.Pp
136Set a password in
137.Xr loader.conf 5
138to prevent booting without password:
139.Pp
140.Bd -literal -offset indent -compact
141bootlock_password="boot"
142.Ed
143.Pp
144Add the following to
145.Xr loader.conf 5
146to generate a prompt at boot to collect GELI credentials for mounting
147.Xr geli 8
148encrypted root device(s):
149.Pp
150.Bd -literal -offset indent -compact
151geom_eli_passphrase_prompt="YES"
152.Ed
153.Sh SEE ALSO
154.Xr loader.conf 5 ,
155.Xr loader 8 ,
156.Xr loader.4th 8
157.Sh HISTORY
158The
159.Nm
160set of commands first appeared in
161.Fx 9.0 .
162.Sh AUTHORS
163The
164.Nm
165set of commands was written by
166.An -nosplit
167.An Devin Teske Aq dteske@FreeBSD.org .
168