lineedit: do not hang on error, but return error indicator.
[oweals/busybox.git] / coreutils / id.c
index d50de4775151087f263c753f5a7e7e7b7e62f396..56286f4d4558415bcbbe2bc52dbdc61bf53d939d 100644 (file)
  * Mini id implementation for busybox
  *
  * Copyright (C) 2000 by Randolph Chung <tausq@debian.org>
+ * Copyright (C) 2008 by Tito Ragusa <farmatito@tiscali.it>
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 
-#include "busybox.h"
-#include <stdio.h>
-#include <unistd.h>
-#include <getopt.h>
-#include <sys/types.h>
+/* BB_AUDIT SUSv3 compliant. */
+/* Hacked by Tito Ragusa (C) 2004 to handle usernames of whatever
+ * length and to be more similar to GNU id.
+ * -Z option support: by Yuichi Nakamura <ynakam@hitachisoft.jp>
+ * Added -G option Tito Ragusa (C) 2008 for SUSv3.
+ */
 
-extern int id_main(int argc, char **argv)
-{
-       int no_user = 0, no_group = 0, print_real = 0;
-       int name_not_number = 0;
-       char user[9], group[9];
-       long gid;
-       long pwnam, grnam;
-       int opt;
-       
-       gid = 0;
+#include "libbb.h"
 
-       while ((opt = getopt(argc, argv, "ugrn")) > 0) {
-               switch (opt) {
-                       case 'u':
-                               no_group++;
-                               break;
-                       case 'g':
-                               no_user++;
-                               break;
-                       case 'r':
-                               print_real++;
-                               break;
-                       case 'n':
-                               name_not_number++;
-                               break;
-                       default:
-                               usage(id_usage);
-               }
-       }
+#if !ENABLE_USE_BB_PWD_GRP
+#if defined(__UCLIBC_MAJOR__) && (__UCLIBC_MAJOR__ == 0)
+#if (__UCLIBC_MINOR__ < 9) || (__UCLIBC_MINOR__ == 9 &&  __UCLIBC_SUBLEVEL__ < 30)
+#error "Sorry, you need at least uClibc version 0.9.30 for id applet to build"
+#endif
+#endif
+#endif
 
-       if (no_user && no_group) usage(id_usage);
+enum {
+       PRINT_REAL      = (1 << 0),
+       NAME_NOT_NUMBER = (1 << 1),
+       JUST_USER       = (1 << 2),
+       JUST_GROUP      = (1 << 3),
+       JUST_ALL_GROUPS = (1 << 4),
+#if ENABLE_SELINUX
+       JUST_CONTEXT    = (1 << 5),
+#endif
+};
 
-       if (argv[optind] == NULL) {
-               if (print_real) {
-                       my_getpwuid(user, getuid());
-                       my_getgrgid(group, getgid());
+static int print_common(unsigned id, const char *name, const char *prefix)
+{
+       if (prefix) {
+               printf("%s", prefix);
+       }
+       if (!(option_mask32 & NAME_NOT_NUMBER) || !name) {
+               printf("%u", id);
+       }
+       if (!option_mask32 || (option_mask32 & NAME_NOT_NUMBER)) {
+               if (name) {
+                       printf(option_mask32 ? "%s" : "(%s)", name);
                } else {
-                       my_getpwuid(user, geteuid());
-                       my_getgrgid(group, getegid());
+                       /* Don't set error status flag in default mode */
+                       if (option_mask32) {
+                               if (ENABLE_DESKTOP)
+                                       bb_error_msg("unknown ID %u", id);
+                               return EXIT_FAILURE;
+                       }
                }
-       } else {
-               strncpy(user, argv[optind], 8);
-               user[8] = '\0';
-           gid = my_getpwnamegid(user);
-               my_getgrgid(group, gid);
        }
+       return EXIT_SUCCESS;
+}
 
-       pwnam=my_getpwnam(user);
-       grnam=my_getgrnam(group);
-       if (gid == -1 || pwnam==-1 || grnam==-1) {
-               error_msg_and_die("%s: No such user\n", user);
-       }
+static int print_group(gid_t id, const char *prefix)
+{
+       return print_common(id, gid2group(id), prefix);
+}
+
+static int print_user(uid_t id, const char *prefix)
+{
+       return print_common(id, uid2uname(id), prefix);
+}
 
-       if (no_group) {
-               if(name_not_number && user)
-                       printf("%s\n",user);
-               else
-                       printf("%ld\n", pwnam);
-       } else if (no_user) {
-               if(name_not_number && group)
-                       printf("%s\n", group);
-               else
-                       printf("%ld\n", grnam);
+/* On error set *n < 0 and return >= 0
+ * If *n is too small, update it and return < 0
+ *  (ok to trash groups[] in both cases)
+ * Otherwise fill in groups[] and return >= 0
+ */
+static int get_groups(const char *username, gid_t rgid, gid_t *groups, int *n)
+{
+       int m;
+
+       if (username) {
+               /* If the user is a member of more than
+                * *n groups, then -1 is returned. Otherwise >= 0.
+                * (and no defined way of detecting errors?!) */
+               m = getgrouplist(username, rgid, groups, n);
+               /* I guess *n < 0 might indicate error. Anyway,
+                * malloc'ing -1 bytes won't be good, so: */
+               //if (*n < 0)
+               //      return 0;
+               //return m;
+               //commented out here, happens below anyway
        } else {
-               printf("uid=%ld(%s) gid=%ld(%s)\n", pwnam, user, grnam, group);
+               /* On error -1 is returned, which ends up in *n */
+               int nn = getgroups(*n, groups);
+               /* 0: nn <= *n, groups[] was big enough; -1 otherwise */
+               m = - (nn > *n);
+               *n = nn;
        }
-       return(0);
+       if (*n < 0)
+               return 0; /* error, don't return < 0! */
+       return m;
 }
 
+int id_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int id_main(int argc UNUSED_PARAM, char **argv)
+{
+       uid_t ruid;
+       gid_t rgid;
+       uid_t euid;
+       gid_t egid;
+       unsigned opt;
+       int i;
+       int status = EXIT_SUCCESS;
+       const char *prefix;
+       const char *username;
+#if ENABLE_SELINUX
+       security_context_t scontext = NULL;
+#endif
+       /* Don't allow -n -r -nr -ug -rug -nug -rnug -uZ -gZ -GZ*/
+       /* Don't allow more than one username */
+       opt_complementary = "?1:u--g:g--u:G--u:u--G:g--G:G--g:r?ugG:n?ugG"
+                        IF_SELINUX(":u--Z:Z--u:g--Z:Z--g:G--Z:Z--G");
+       opt = getopt32(argv, "rnugG" IF_SELINUX("Z"));
 
-/* END CODE */
+       username = argv[optind];
+       if (username) {
+               struct passwd *p = xgetpwnam(username);
+               euid = ruid = p->pw_uid;
+               egid = rgid = p->pw_gid;
+       } else {
+               egid = getegid();
+               rgid = getgid();
+               euid = geteuid();
+               ruid = getuid();
+       }
+       /* JUST_ALL_GROUPS ignores -r PRINT_REAL flag even if man page for */
+       /* id says: print the real ID instead of the effective ID, with -ugG */
+       /* in fact in this case egid is always printed if egid != rgid */
+       if (!opt || (opt & JUST_ALL_GROUPS)) {
+               gid_t *groups;
+               int n;
+
+               if (!opt) {
+                       /* Default Mode */
+                       status |= print_user(ruid, "uid=");
+                       status |= print_group(rgid, " gid=");
+                       if (euid != ruid)
+                               status |= print_user(euid, " euid=");
+                       if (egid != rgid)
+                               status |= print_group(egid, " egid=");
+               } else {
+                       /* JUST_ALL_GROUPS */
+                       status |= print_group(rgid, NULL);
+                       if (egid != rgid)
+                               status |= print_group(egid, " ");
+               }
+               /* We are supplying largish buffer, trying
+                * to not run get_groups() twice. That might be slow
+                * ("user database in remote SQL server" case) */
+               groups = xmalloc(64 * sizeof(gid_t));
+               n = 64;
+               if (get_groups(username, rgid, groups, &n) < 0) {
+                       /* Need bigger buffer after all */
+                       groups = xrealloc(groups, n * sizeof(gid_t));
+                       get_groups(username, rgid, groups, &n);
+               }
+               if (n > 0) {
+                       /* Print the list */
+                       prefix = " groups=";
+                       for (i = 0; i < n; i++) {
+                               if (opt && (groups[i] == rgid || groups[i] == egid))
+                                       continue;
+                               status |= print_group(groups[i], opt ? " " : prefix);
+                               prefix = ",";
+                       }
+               } else if (n < 0) { /* error in get_groups() */
+                       if (!ENABLE_DESKTOP)
+                               bb_error_msg_and_die("can't get groups");
+                       else
+                               return EXIT_FAILURE;
+               }
+               if (ENABLE_FEATURE_CLEAN_UP)
+                       free(groups);
+#if ENABLE_SELINUX
+               if (is_selinux_enabled()) {
+                       if (getcon(&scontext) == 0)
+                               printf(" context=%s", scontext);
+               }
+#endif
+       } else if (opt & PRINT_REAL) {
+               euid = ruid;
+               egid = rgid;
+       }
+
+       if (opt & JUST_USER)
+               status |= print_user(euid, NULL);
+       else if (opt & JUST_GROUP)
+               status |= print_group(egid, NULL);
+#if ENABLE_SELINUX
+       else if (opt & JUST_CONTEXT) {
+               selinux_or_die();
+               if (username || getcon(&scontext)) {
+                       bb_error_msg_and_die("can't get process context%s",
+                               username ? " for a different user" : "");
+               }
+               fputs(scontext, stdout);
+       }
+       /* freecon(NULL) seems to be harmless */
+       if (ENABLE_FEATURE_CLEAN_UP)
+               freecon(scontext);
+#endif
+       bb_putchar('\n');
+       fflush_stdout_and_exit(status);
+}