deluser: add optional support for removing users from groups

(by Tito <farmatito@tiscali.it>)

diff --git a/include/usage.h b/include/usage.h
index 2fb8112b0a5dde0a7ac99d22667f618894272182..afcc4b3d794e36595586a80724e26a6d8f7f2878 100644 (file)
--- a/include/usage.h
+++ b/include/usage.h
@@ -571,9 +571,10 @@
        "Deallocate unused virtual terminal /dev/ttyN"
 
 #define delgroup_trivial_usage \
-       "GROUP"
+        USE_FEATURE_DEL_USER_FROM_GROUP("[USER] ")"GROUP"
 #define delgroup_full_usage \
-       "Delete group GROUP from the system"
+       "Delete group GROUP from the system" \
+        USE_FEATURE_DEL_USER_FROM_GROUP(" or user USER from group GROUP")
 
 #define deluser_trivial_usage \
        "USER"

diff --git a/loginutils/Config.in b/loginutils/Config.in
index 1d52cdfe56912b14d3561c813fc956fbc17f7865..e8ab9ec3c73270f8b43b867be4b23612df5f8591 100644 (file)
--- a/loginutils/Config.in
+++ b/loginutils/Config.in
@@ -74,6 +74,14 @@ config DELGROUP
        help
          Utility for deleting a group account.
 
+config FEATURE_DEL_USER_FROM_GROUP
+       bool "Support for removing users from groups."
+       default n
+       depends on DELGROUP
+       help
+         If called with two non-option arguments, deluser 
+         or delgroup will remove an user from a specified group.
+
 config ADDUSER
        bool "adduser"
        default n

diff --git a/loginutils/deluser.c b/loginutils/deluser.c
index e9bde00bd4a8aa47a0574bf48417ded9cd943f5b..2781df3192cd20c2437e9259789b88858d973f13 100644 (file)
--- a/loginutils/deluser.c
+++ b/loginutils/deluser.c
@@ -1,10 +1,10 @@
 /* vi: set sw=4 ts=4: */
 /*
- * deluser (remove lusers from the system ;) for TinyLogin
+ * deluser/delgroup implementation for busybox
  *
  * Copyright (C) 1999 by Lineo, inc. and John Beppu
  * Copyright (C) 1999,2000,2001 by John Beppu <beppu@codepoet.org>
- * Unified with delgroup by Tito Ragusa <farmatito@tiscali.it>
+ * Copyright (C) 2007 by Tito Ragusa <farmatito@tiscali.it>
  *
  * Licensed under GPL version 2, see file LICENSE in this tarball for details.
  *
@@ -12,72 +12,114 @@
 
 #include "busybox.h"
 
-static void del_line_matching(const char *login, const char *filename)
+/* Status */
+#define STATUS_OK            0
+#define NAME_NOT_FOUND       1
+#define MEMBER_NOT_FOUND     2
+
+static void del_line_matching(char **args,
+               const char *filename,
+               FILE *(*fopen_func)(const char *fileName, const char *mode))
 {
-       char *line;
        FILE *passwd;
-       int len = strlen(login);
-       int found = 0;
-       llist_t *plist = NULL;
+       smallint error = NAME_NOT_FOUND;
+       char *name = (ENABLE_FEATURE_DEL_USER_FROM_GROUP && args[2]) ? args[2] : args[1];
+       char *line, *del;
+       char *new = xzalloc(1);
 
-       passwd = fopen_or_warn(filename, "r");
-       if (!passwd) return;
+       passwd = fopen_func(filename, "r");
+       if (passwd) {
+               while ((line = xmalloc_fgets(passwd))) {
+                       int len = strlen(name);
 
-       while ((line = xmalloc_fgets(passwd))) {
-               if (!strncmp(line, login, len)
-                && line[len] == ':'
-               ) {
-                       found++;
+                       if (strncmp(line, name, len) == 0
+                        && line[len] == ':'
+                       ) {
+                               error = STATUS_OK;
+                               if (ENABLE_FEATURE_DEL_USER_FROM_GROUP) {
+                                       struct group *gr;
+                                       char *p;
+                                       if (args[2]
+                                        /* There were two args on commandline */
+                                        && (gr = getgrnam(name))
+                                        /* The group was not deleted in the meanwhile */
+                                        && (p = strrchr(line, ':'))
+                                        /* We can find a pointer to the last ':' */
+                                       ) {
+                                               error = MEMBER_NOT_FOUND;
+                                               /* Move past ':' (worst case to '\0') and cut the line */
+                                               p[1] = '\0';
+                                               /* Reuse p */
+                                               for (p = xzalloc(1); *gr->gr_mem != NULL; gr->gr_mem++) {
+                                                       /* Add all the other group members */
+                                                       if (strcmp(args[1], *gr->gr_mem) != 0) {
+                                                               del = p;
+                                                               p = xasprintf("%s%s%s", p, p[0] ? "," : "", *gr->gr_mem);
+                                                               free(del);
+                                                       } else
+                                                               error = STATUS_OK;
+                                               }
+                                               /* Recompose the line */
+                                               line = xasprintf("%s%s\n", line, p);
+                                               if (ENABLE_FEATURE_CLEAN_UP) free(p);
+                                       } else
+                                               goto skip;
+                               }
+                       }
+                       del = new;
+                       new = xasprintf("%s%s", new, line);
+                       free(del);
+ skip:
                        free(line);
-               } else {
-                       llist_add_to_end(&plist, line);
                }
-       }
 
-       if (!ENABLE_FEATURE_CLEAN_UP) {
-               if (!found) {
-                       bb_error_msg("can't find '%s' in '%s'", login, filename);
-                       return;
-               }
-               passwd = fopen_or_warn(filename, "w");
-               if (passwd)
-                       while ((line = llist_pop(&plist)))
-                               fputs(line, passwd);
-       } else {
-               if (!found) {
-                       bb_error_msg("can't find '%s' in '%s'", login, filename);
-                       goto clean_up;
-               }
-               fclose(passwd);
-               passwd = fopen_or_warn(filename, "w");
-               if (passwd) {
- clean_up:
-                       while ((line = llist_pop(&plist))) {
-                               if (found) fputs(line, passwd);
-                               free(line);
+               if (ENABLE_FEATURE_CLEAN_UP) fclose(passwd);
+
+               if (error) {
+                       if (ENABLE_FEATURE_DEL_USER_FROM_GROUP && error == MEMBER_NOT_FOUND) {
+                               /* Set the correct values for error message */
+                               filename = name;
+                               name = args[1];
+                       }
+                       bb_error_msg("can't find %s in %s", name, filename);
+               } else {
+                       passwd = fopen_func(filename, "w");
+                       if (passwd) {
+                               fputs(new, passwd);
+                               if (ENABLE_FEATURE_CLEAN_UP) fclose(passwd);
                        }
-                       fclose(passwd);
                }
        }
+       free(new);
 }
 
 int deluser_main(int argc, char **argv);
 int deluser_main(int argc, char **argv)
 {
-       if (argc != 2)
-               bb_show_usage();
-
-       if (ENABLE_DELUSER
-        && (!ENABLE_DELGROUP || applet_name[3] == 'u')
+       if (argc == 2 
+        || (ENABLE_FEATURE_DEL_USER_FROM_GROUP 
+           && (applet_name[3] == 'g' && argc == 3))
        ) {
-               del_line_matching(argv[1], bb_path_passwd_file);
+               if (geteuid())
+                       bb_error_msg_and_die(bb_msg_perm_denied_are_you_root);
+               
+               if ((ENABLE_FEATURE_DEL_USER_FROM_GROUP && argc != 3) 
+                || ENABLE_DELUSER
+                || (ENABLE_DELGROUP && ENABLE_DESKTOP)
+               ) {
+                       if (ENABLE_DELUSER
+                        && (!ENABLE_DELGROUP || applet_name[3] == 'u')
+                       ) {
+                               del_line_matching(argv, bb_path_passwd_file, xfopen);
+                               if (ENABLE_FEATURE_SHADOWPASSWDS)
+                                       del_line_matching(argv, bb_path_shadow_file, fopen_or_warn);
+                       } else if (ENABLE_DESKTOP && ENABLE_DELGROUP && getpwnam(argv[1]))
+                               bb_error_msg_and_die("can't remove primary group of user %s", argv[1]);
+               }
+               del_line_matching(argv, bb_path_group_file, xfopen);
                if (ENABLE_FEATURE_SHADOWPASSWDS)
-                       del_line_matching(argv[1], bb_path_shadow_file);
-       }
-       del_line_matching(argv[1], bb_path_group_file);
-       if (ENABLE_FEATURE_SHADOWPASSWDS)
-               del_line_matching(argv[1], bb_path_gshadow_file);
-
-       return EXIT_SUCCESS;
+                       del_line_matching(argv, bb_path_gshadow_file, fopen_or_warn);
+               return EXIT_SUCCESS;
+       } else
+               bb_show_usage();
 }
-

diff --git a/scripts/defconfig b/scripts/defconfig
index 009026e5acdf6f49d04df2982221fb9d40de8223..c9086eb13e346eca20b25b436c98471bf683e02a 100644 (file)
--- a/scripts/defconfig
+++ b/scripts/defconfig
@@ -349,6 +349,7 @@ CONFIG_USE_BB_PWD_GRP=y
 CONFIG_ADDGROUP=y
 CONFIG_FEATURE_ADDUSER_TO_GROUP=y
 CONFIG_DELGROUP=y
+CONFIG_FEATURE_DEL_USER_FROM_GROUP=y
 CONFIG_ADDUSER=y
 CONFIG_DELUSER=y
 CONFIG_GETTY=y