deluser: 2nd attempt at deluser/delgroup size reduction and improvements

Signed-off-by: Tito Ragusa <farmatito@tiscali.it>
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>

diff --git a/loginutils/deluser.c b/loginutils/deluser.c
index 08ca266d0e8de5171854a614517482906abd4ea7..5a159b2050f7606fd16ed8ffcade91aa3ef5980f 100644 (file)
--- a/loginutils/deluser.c
+++ b/loginutils/deluser.c
@@ -14,41 +14,82 @@
 int deluser_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int deluser_main(int argc, char **argv)
 {
-       if (argc != 2
-        && (!ENABLE_FEATURE_DEL_USER_FROM_GROUP
-           || applet_name[3] != 'g'
-           || argc != 3)
-       ) {
-               bb_show_usage();
-       }
+       /* User or group name */
+       char *name;
+       /* Username (non-NULL only in "delgroup USER GROUP" case) */
+       char *member;
+       /* Name of passwd or group file */
+       const char *pfile;
+       /* Name of shadow or gshadow file */
+       const char *sfile;
+       /* Are we deluser or delgroup? */
+       bool do_deluser = (ENABLE_DELUSER && (!ENABLE_DELGROUP || applet_name[3] == 'u'));
 
-       if (geteuid())
+       if (geteuid() != 0)
                bb_error_msg_and_die(bb_msg_perm_denied_are_you_root);
 
-       if (ENABLE_DELUSER && applet_name[3] == 'u') {
-               /* deluser USER */
-               if (update_passwd(bb_path_passwd_file, argv[1], NULL, NULL) < 0)
-                       return EXIT_FAILURE;
-               if (ENABLE_FEATURE_SHADOWPASSWDS)
-                       if (update_passwd(bb_path_shadow_file, argv[1], NULL, NULL) < 0)
-                               return EXIT_FAILURE;
-       } else if (ENABLE_DELGROUP) {
-               /* delgroup ... */
-               if (!ENABLE_FEATURE_DEL_USER_FROM_GROUP || argc != 3) {
-                       /* delgroup GROUP */
-                       if (update_passwd(bb_path_group_file, argv[1], NULL, NULL) < 0)
-                               return EXIT_FAILURE;
+       name = argv[1];
+       member = NULL;
+
+       switch (argc) {
+       case 3:
+               if (!ENABLE_FEATURE_DEL_USER_FROM_GROUP || do_deluser)
+                       break;
+               /* It's "delgroup USER GROUP" */
+               member = name;
+               name = argv[2];
+               /* Fallthrough */
+
+       case 2:
+               if (do_deluser) {
+                       /* "deluser USER" */
+                       xgetpwnam(name); /* bail out if USER is wrong */
+                       pfile = bb_path_passwd_file;
                        if (ENABLE_FEATURE_SHADOWPASSWDS)
-                               if (update_passwd(bb_path_gshadow_file, argv[1], NULL, NULL) < 0)
-                                       return EXIT_FAILURE;
+                               sfile = bb_path_shadow_file;
                } else {
-                       /* delgroup USER GROUP */
-                       if (update_passwd(bb_path_group_file, argv[2], NULL, argv[1]) < 0)
-                               return EXIT_FAILURE;
+ do_delgroup:
+                       /* "delgroup GROUP" or "delgroup USER GROUP" */
+                       xgetgrnam(name); /* bail out if GROUP is wrong */
+                       if (!member) {
+                               /* "delgroup GROUP".
+                                * If user with tha same name exists,
+                                * bail out.
+                                */
+//BUG: check should be done by GID, not by matching name!
+//1. find GROUP's GID
+//2. check that /etc/passwd doesn't have lines of the form
+//   user:pwd:uid:GID:...
+//3. bail out if at least one such line exists
+                               if (getpwnam(name) != NULL)
+                                       bb_error_msg_and_die("'%s' still has '%s' as their primary group!", name, name);
+                       }
+                       pfile = bb_path_group_file;
                        if (ENABLE_FEATURE_SHADOWPASSWDS)
-                               if (update_passwd(bb_path_gshadow_file, argv[2], NULL, argv[1]) < 0)
-                                       return EXIT_FAILURE;
+                               sfile = bb_path_gshadow_file;
+               }
+
+               /* Modify pfile, then sfile */
+               do {
+                       if (update_passwd(pfile, name, NULL, member) == -1)
+                               return EXIT_FAILURE;
+                       if (ENABLE_FEATURE_SHADOWPASSWDS) {
+                               pfile = sfile;
+                               sfile = NULL;
+                       }
+               } while (ENABLE_FEATURE_SHADOWPASSWDS && pfile);
+
+               if (ENABLE_DELGROUP && do_deluser) {
+                       /* "deluser USER" also should try to delete
+                        * same-named group. IOW: do "delgroup USER"
+                        */
+//TODO: check how it actually works in upstream.
+//I suspect it is only done if group has no more members.
+                       do_deluser = 0;
+                       goto do_delgroup;
                }
+               return EXIT_SUCCESS;
        }
-       return EXIT_SUCCESS;
+       /* Reached only if number of command line args is wrong */
+       bb_show_usage();
 }