[illumos-Developer] webrev: 1213 chmod could handle empty access mask as wildcard when removing user/group ACEs

[Yuri Pankov]

Hi,

https://www.xvoid.org/illumos/webrev/chmod/

The idea is to use empty access mask as wildcard when removing
user/group ACes (I hope the example is readable):

$ mkdir -p dir1/dir2/dir3; \
  chmod -R A+user:yuri:rwx:allow,user:bin:rwx:deny dir1; \
  ls -Vd dir1/dir2; \
  LD_PRELOAD=~/ws/chmod/proto/root_i386/usr/lib/libsec.so.1 chmod \
  A-user:bin::deny dir1/dir2; \
  ls -Vd dir1/dir2; \
  ls -Vd dir1/dir2/dir3; \
  LD_PRELOAD=~/ws/chmod/proto/root_i386/usr/lib/libsec.so.1 chmod -R \
  A-user:yuri::allow dir1; \
  ls -Vd dir1/dir2/dir3
drwxr-xr-x+  3 yuri     staff          3 Jul 19 02:25 dir1/dir2
              user:yuri:rwx-----------:-------:allow
               user:bin:rwx-----------:-------:deny
                 owner@:rwxp--aARWcCos:-------:allow
                 group@:r-x---a-R-c--s:-------:allow
              everyone@:r-x---a-R-c--s:-------:allow
drwxr-xr-x+  3 yuri     staff          3 Jul 19 02:25 dir1/dir2
              user:yuri:rwx-----------:-------:allow
                 owner@:rwxp--aARWcCos:-------:allow
                 group@:r-x---a-R-c--s:-------:allow
              everyone@:r-x---a-R-c--s:-------:allow
drwxr-xr-x+  2 yuri     staff          2 Jul 19 02:25 dir1/dir2/dir3
              user:yuri:rwx-----------:-------:allow
               user:bin:rwx-----------:-------:deny
                 owner@:rwxp--aARWcCos:-------:allow
                 group@:r-x---a-R-c--s:-------:allow
              everyone@:r-x---a-R-c--s:-------:allow
drwxr-xr-x+  2 yuri     staff          2 Jul 19 02:25 dir1/dir2/dir3
               user:bin:rwx-----------:-------:deny
                 owner@:rwxp--aARWcCos:-------:allow
                 group@:r-x---a-R-c--s:-------:allow
              everyone@:r-x---a-R-c--s:-------:allow

Another change to make this more usable is to deny creating ACEs with
empty access mask (they don't make any sense, do they?).

All changed functions are used only by cmd/chmod, so this shouldn't have
any side effects.


Yuri