xref: /freebsd/libexec/ftpd/ftpchroot.5 (revision eb69d1f144a6fcc765d1b9d44a5ae8082353e70b)
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25.\" $FreeBSD$
26.\"
27.Dd January 26, 2003
28.Dt FTPCHROOT 5
29.Os
30.Sh NAME
31.Nm ftpchroot
32.Nd "list users and groups subject to FTP access restrictions"
33.Sh DESCRIPTION
34The file
35.Nm
36is read by
37.Xr ftpd 8
38at the beginning of an FTP session, after having authenticated the user.
39Each line in
40.Nm
41corresponds to a user or group.
42If a line in
43.Nm
44matches the current user or a group he is a member of,
45access restrictions will be applied to this
46session by changing its root directory with
47.Xr chroot 2
48to that specified on the line or to the user's login directory.
49.Pp
50The order of records in
51.Nm
52is important because the first match will be used.
53Fields on each line are separated by tabs or spaces.
54.Pp
55The first field specifies a user or group name.
56If it is prefixed by an
57.Dq at
58sign,
59.Ql @ ,
60it specifies a group name;
61the line will match each user who is a member of this group.
62As a special case, a single
63.Ql @
64in this field will match any user.
65A username is specified otherwise.
66.Pp
67The optional second field describes the directory for the user
68or each member of the group to be locked up in using
69.Xr chroot 2 .
70Be it omitted, the user's login directory will be used.
71If it is not an absolute pathname, then it will be relative
72to the user's login directory.
73If it contains the
74.Pa /./
75separator,
76.Xr ftpd 8
77will treat its left-hand side as the name of the directory to do
78.Xr chroot 2
79to, and its right-hand side to change the current directory to afterwards.
80.Sh FILES
81.Bl -tag -width ".Pa /etc/ftpchroot" -compact
82.It Pa /etc/ftpchroot
83.El
84.Sh EXAMPLES
85These lines in
86.Nm
87will lock up the user
88.Dq Li webuser
89and each member of the group
90.Dq Li hostee
91in their respective login directories:
92.Bd -literal -offset indent
93webuser
94@hostee
95.Ed
96.Pp
97And this line will tell
98.Xr ftpd 8
99to lock up the user
100.Dq Li joe
101in
102.Pa /var/spool/ftp
103and then to change the current directory to
104.Pa /joe ,
105which is relative to the session's new root:
106.Pp
107.Dl "joe	/var/spool/ftp/./joe"
108.Pp
109And finally the following line will lock up every user connecting
110through FTP in his respective
111.Pa ~/public_html ,
112thus lowering possible impact on the system
113from intrinsic insecurity of FTP:
114.Pp
115.Dl "@	public_html"
116.Sh SEE ALSO
117.Xr chroot 2 ,
118.Xr group 5 ,
119.Xr passwd 5 ,
120.Xr ftpd 8
121