1PAM_SECURETTY(8) Linux-PAM Manual PAM_SECURETTY(8)
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6 pam_securetty - Limit root login to special devices
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9 pam_securetty.so [debug]
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12 pam_securetty is a PAM module that allows root logins only if the user
13 is logging in on a "secure" tty, as defined by the listing in the
14 securetty file. pam_securetty checks at first, if /etc/securetty
15 exists. If not and it was built with vendordir support, it will use
16 <vendordir>/securetty. pam_securetty also checks that the securetty
17 files are plain files and not world writable. It will also allow root
18 logins on the tty specified with console= switch on the kernel command
19 line and on ttys from the /sys/class/tty/console/active.
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21 This module has no effect on non-root users and requires that the
22 application fills in the PAM_TTY item correctly.
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24 For canonical usage, should be listed as a required authentication
25 method before any sufficient authentication methods.
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28 debug
29 Print debug information.
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31 noconsole
32 Do not automatically allow root logins on the kernel console
33 device, as specified on the kernel command line or by the sys file,
34 if it is not also specified in the securetty file.
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37 Only the auth module type is provided.
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40 PAM_SUCCESS
41 The user is allowed to continue authentication. Either the user is
42 not root, or the root user is trying to log in on an acceptable
43 device.
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45 PAM_AUTH_ERR
46 Authentication is rejected. Either root is attempting to log in via
47 an unacceptable device, or the securetty file is world writable or
48 not a normal file.
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50 PAM_BUF_ERR
51 Memory buffer error.
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53 PAM_CONV_ERR
54 The conversation method supplied by the application failed to
55 obtain the username.
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57 PAM_INCOMPLETE
58 The conversation method supplied by the application returned
59 PAM_CONV_AGAIN.
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61 PAM_SERVICE_ERR
62 An error occurred while the module was determining the user's name
63 or tty, or the module could not open the securetty file.
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65 PAM_USER_UNKNOWN
66 The module could not find the user name in the /etc/passwd file to
67 verify whether the user had a UID of 0. Therefore, the results of
68 running this module are ignored.
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71 auth required pam_securetty.so
72 auth required pam_unix.so
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77 securetty(5), pam.conf(5), pam.d(5), pam(8)
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80 pam_securetty was written by Elliot Lee <sopwith@cuc.edu>.
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84Linux-PAM Manual 09/03/2021 PAM_SECURETTY(8)