Document new list Defaults type and convert env_keep and env_delete

to lists.
Document new env_check option.

diff --git a/sudoers.pod b/sudoers.pod
index 8e9db38df64eb428c036ef75004f69668a4cee69..174802debc44313f0c6d0855c6e1f5997139c86d 100644 (file)
--- a/sudoers.pod
+++ b/sudoers.pod
@@ -1,5 +1,5 @@
 =cut
-Copyright (c) 1994-1996,1998-2000 Todd C. Miller <Todd.Miller@courtesan.com>
+Copyright (c) 1994-1996,1998-2001 Todd C. Miller <Todd.Miller@courtesan.com>
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without
@@ -212,14 +212,21 @@ value on a matching line takes effect.
  Default_Entry ::= Default_Type Parameter_List
 
  Parameter ::= Parameter '=' Value ||
+              Parameter '+=' Value ||
+              Parameter '-=' Value ||
               '!'* Parameter ||
 
-Parameters may be B<flags>, B<integer> values, or B<strings>.  Flags
-are implicitly boolean and can be turned off via the '!' operator.
-Some integer and string parameters may also be used in a boolean
-context to disable them.  Values may be enclosed in double quotes
-(C<">) when they contain multiple words.  Special characters may
-be escaped with a backslash (C<\>).
+Parameters may be B<flags>, B<integer> values, B<strings>, or B<lists>.
+Flags are implicitly boolean and can be turned off via the '!'
+operator.  Some integer, string and list parameters may also be
+used in a boolean context to disable them.  Values may be enclosed
+in double quotes (C<">) when they contain multiple words.  Special
+characters may be escaped with a backslash (C<\>).
+
+Lists have two additional assignment operators, C<+=> and C<-=>.
+These operators are used to add to and delete from a list respectively.
+It is not an error to use the C<-=> operator to remove an element
+that does not exist in a list.
 
 B<Flags>:
 
@@ -513,25 +520,6 @@ Defaults to C<@goodpri@>.
 Syslog priority to use when user authenticates unsuccessfully.
 Defaults to C<@badpri@>.
 
-=item env_delete
-
-A double-quoted, space-separated list of environment variables
-to be removed from the user's environment.  By default this list
-will B<replace> sudo's builtin list of environment variables to remove.
-To B<append> to the builtin list instead of replacing it, the argument
-to I<env_delete> should start with a I<+> (think "add").
-The default list of environment variable to remove is printed
-when B<sudo> is run by root with the I<-V> option.
-
-=item env_keep
-
-A double-quoted, space-separated list of environment variables
-to be preserved in the user's environment.  When used in conjuction
-with the I<env_reset> option, this allows fine control over the
-environment B<sudo>-spawned processes will get.  If the I<env_reset>
-option is not used, I<env_keep> can be used to make exceptions to
-the built in list of "dangerous" environment variables.
-
 =item editor
 
 A colon (':') separated list of editors allowed to be used with
@@ -629,6 +617,41 @@ The default value is `any'.
 
 =back 12
 
+B<Lists that can be used in a boolean context>:
+
+=over 12
+
+=item env_check
+
+A double-quoted, space-separated list of environment variables to
+be removed from the user's environment if the variable's value
+contains C<%> or C</> characters.  This can be used to guard against
+printf-style format vulnerabilties in poorly-written programs.  The
+list can be replaced, added to, deleted from, or disabled by using
+the C<=>, C<+=>, C<-=>, and <!> operators respectively.  The default
+list of environment variable to check is printed when B<sudo> is
+run by root with the I<-V> option.
+
+=item env_delete
+
+A double-quoted, space-separated list of environment variables to
+be removed from the user's environment.  The list can be replaced,
+added to, deleted from, or disabled by using the C<=>, C<+=>, C<-=>,
+and <!> operators respectively.  The default list of environment
+variable to remove is printed when B<sudo> is run by root with the
+I<-V> option.
+
+=item env_keep
+
+A double-quoted, space-separated list of environment variables to
+be preserved in the user's environment when the I<env_reset> option
+is in effect.  This allows fine-grained control over the environment
+B<sudo>-spawned processes will get.  The list can be replaced, added
+to, deleted from, or disabled by using the C<=>, C<+=>, C<-=>, and
+<!> operators respectively.  This list has no default members.
+
+=back 12
+
 When logging via syslog(3), B<sudo> accepts the following values for the syslog
 facility (the value of the B<syslog> Parameter): B<authpriv> (if your OS
 supports it), B<auth>, B<daemon>, B<user>, B<local0>, B<local1>, B<local2>,