/usr/share/freeradius/dictionary.usr.illegal is in freeradius-common 2.1.12+dfsg-1.2ubuntu8.2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45  | # -*- text -*-
##############################################################################
#
#	USE dictionary that illegally uses the RFC space.
#
#	$Id$
#
##############################################################################
#
#	USR specific attributes
#
# Prompt value should be 1 for echo, 0 for no echo, default 1.
#ATTRIBUTE	Prompt			64	integer
ATTRIBUTE	Multi-Link-Flag				126	integer
ATTRIBUTE	Char-Noecho				250	integer
#
#	USR specific Integer Translations
#
VALUE	Termination-Action		Manage-Resources	2
VALUE	Acct-Status-Type		Modem-Start		4
VALUE	Acct-Status-Type		Modem-Stop		5
VALUE	Acct-Status-Type		Cancel			6
VALUE	Multi-Link-Flag			True			1
VALUE	Multi-Link-Flag			False			0
#	USR specific Authentication Types
#
#  These are commented out because the conflict with the standard
#  definitions.
#
#VALUE		Acct-Authentic		None			0
#VALUE		Acct-Authentic		Remote			3
#VALUE		Acct-Authentic		RADIUS			4
#VALUE		Acct-Authentic		MNET			5
#VALUE		Acct-Authentic		KCHAP			6
#VALUE		Acct-Authentic		TACACS			7
#VALUE		Acct-Authentic		Realm			8
#VALUE		Acct-Authentic		Local			9
#VALUE		Acct-Authentic		File			10
#VALUE		Acct-Authentic		Local-VPN		11
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