* Mini id implementation for busybox
*
* Copyright (C) 2000 by Randolph Chung <tausq@debian.org>
+ * Copyright (C) 2008 by Tito Ragusa <farmatito@tiscali.it>
*
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
-
-/* BB_AUDIT SUSv3 _NOT_ compliant -- option -G is not currently supported. */
-/* Hacked by Tito Ragusa (C) 2004 to handle usernames of whatever length and to
- * be more similar to GNU id.
+/* 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.
*/
+//config:config ID
+//config: bool "id (7 kb)"
+//config: default y
+//config: help
+//config: id displays the current user and group ID names.
+//config:
+//config:config GROUPS
+//config: bool "groups (6.7 kb)"
+//config: default y
+//config: help
+//config: Print the group names associated with current user id.
+
+//applet:IF_GROUPS(APPLET_NOEXEC(groups, id, BB_DIR_USR_BIN, BB_SUID_DROP, groups))
+//applet:IF_ID( APPLET_NOEXEC(id, id, BB_DIR_USR_BIN, BB_SUID_DROP, id ))
+
+//kbuild:lib-$(CONFIG_GROUPS) += id.o
+//kbuild:lib-$(CONFIG_ID) += id.o
+
+/* BB_AUDIT SUSv3 compliant. */
+
+//usage:#define id_trivial_usage
+//usage: "[OPTIONS] [USER]"
+//usage:#define id_full_usage "\n\n"
+//usage: "Print information about USER or the current user\n"
+//usage: IF_SELINUX(
+//usage: "\n -Z Security context"
+//usage: )
+//usage: "\n -u User ID"
+//usage: "\n -g Group ID"
+//usage: "\n -G Supplementary group IDs"
+//usage: "\n -n Print names instead of numbers"
+//usage: "\n -r Print real ID instead of effective ID"
+//usage:
+//usage:#define id_example_usage
+//usage: "$ id\n"
+//usage: "uid=1000(andersen) gid=1000(andersen)\n"
-#include "busybox.h"
-#include <stdio.h>
-#include <unistd.h>
-#include <sys/types.h>
+//usage:#define groups_trivial_usage
+//usage: "[USER]"
+//usage:#define groups_full_usage "\n\n"
+//usage: "Print the group memberships of USER or for the current process"
+//usage:
+//usage:#define groups_example_usage
+//usage: "$ groups\n"
+//usage: "andersen lp dialout cdrom floppy\n"
-#define PRINT_REAL 1
-#define NAME_NOT_NUMBER 2
-#define JUST_USER 4
-#define JUST_GROUP 8
+#include "libbb.h"
+
+/* This is a NOEXEC applet. Be very careful! */
+
+#if !ENABLE_USE_BB_PWD_GRP
+#if defined(__UCLIBC__) && UCLIBC_VERSION < KERNEL_VERSION(0, 9, 30)
+#error "Sorry, you need at least uClibc version 0.9.30 for id applet to build"
+#endif
+#endif
+
+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
-#define JUST_CONTEXT 16
+ JUST_CONTEXT = (1 << 5),
#endif
+};
+
+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 {
+ /* 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;
+ }
+ }
+ }
+ return EXIT_SUCCESS;
+}
-static short printf_full(unsigned int id, const char *arg, const char prefix)
+static int print_group(gid_t id, const char *prefix)
{
- const char *fmt = "%cid=%u";
- short status = EXIT_FAILURE;
+ 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 (arg) {
- fmt = "%cid=%u(%s)";
- status = EXIT_SUCCESS;
+/* 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;
}
- printf(fmt, prefix, id, arg);
- return status;
+
+ *n = getgroups(*n, groups);
+ if (*n >= 0)
+ return *n;
+ /* Error */
+ if (errno == EINVAL) /* *n is too small? */
+ *n = getgroups(0, groups); /* get needed *n */
+ /* if *n >= 0, return -1 (got new *n), else return 0 (error): */
+ return -(*n >= 0);
}
-int id_main(int argc, char **argv);
-int id_main(int argc, char **argv)
+int id_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int id_main(int argc UNUSED_PARAM, char **argv)
{
- struct passwd *p;
- uid_t uid;
- gid_t gid;
- unsigned long flags;
- short status;
+ 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;
+ security_context_t scontext = NULL;
#endif
- /* Don't allow -n -r -nr -ug -rug -nug -rnug */
- /* Don't allow more than one username */
- opt_complementary = "?1:?:u--g:g--u:r?ug:n?ug" USE_SELINUX(":u--Z:Z--u:g--Z:Z--g");
- flags = getopt32(argc, argv, "rnug" USE_SELINUX("Z"));
-
- /* This values could be overwritten later */
- uid = geteuid();
- gid = getegid();
- if (flags & PRINT_REAL) {
- uid = getuid();
- gid = getgid();
+
+ if (ENABLE_GROUPS && (!ENABLE_ID || applet_name[0] == 'g')) {
+ /* TODO: coreutils groups prepend "USER : " prefix,
+ * and accept many usernames. Example:
+ * # groups root root
+ * root : root
+ * root : root
+ */
+ opt = option_mask32 = getopt32(argv, "") | JUST_ALL_GROUPS | NAME_NOT_NUMBER;
+ } else {
+ /* Don't allow -n -r -nr -ug -rug -nug -rnug -uZ -gZ -GZ*/
+ /* Don't allow more than one username */
+ opt = getopt32(argv, "^"
+ "rnugG" IF_SELINUX("Z")
+ "\0"
+ "?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")
+ );
}
- if (argv[optind]) {
- p = getpwnam(argv[optind]);
- /* xuname2uid is needed because it exits on failure */
- uid = xuname2uid(argv[optind]);
- gid = p->pw_gid;
- /* in this case PRINT_REAL is the same */
+ 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 (flags & (JUST_GROUP | JUST_USER USE_SELINUX(| JUST_CONTEXT))) {
- /* JUST_GROUP and JUST_USER are mutually exclusive */
- if (flags & NAME_NOT_NUMBER) {
- /* bb_getpwuid and bb_getgrgid exit on failure so puts cannot segfault */
- puts((flags & JUST_USER) ? bb_getpwuid(NULL, uid, -1 ) : bb_getgrgid(NULL, gid, -1 ));
+ 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 {
- if (flags & JUST_USER) {
- printf("%u\n", uid);
- }
- if (flags & JUST_GROUP) {
- printf("%u\n", gid);
- }
- }
-
+ /* 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(groups[0]));
+ n = 64;
+ if (get_groups(username, rgid, groups, &n) < 0) {
+ /* Need bigger buffer after all */
+ groups = xrealloc(groups, n * sizeof(groups[0]));
+ 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_simple_error_msg_and_die("can't get groups");
+ return EXIT_FAILURE;
+ }
+ if (ENABLE_FEATURE_CLEAN_UP)
+ free(groups);
#if ENABLE_SELINUX
- if (flags & JUST_CONTEXT) {
- selinux_or_die();
- if (argc - optind == 1) {
- bb_error_msg_and_die("user name can't be passed with -Z");
- }
-
- if (getcon(&scontext)) {
- bb_error_msg_and_die("can't get process context");
- }
- printf("%s\n", scontext);
- }
-#endif
- /* exit */
- fflush_stdout_and_exit(EXIT_SUCCESS);
+ if (is_selinux_enabled()) {
+ if (getcon(&scontext) == 0)
+ printf(" context=%s", scontext);
+ }
+#endif
+ } else if (opt & PRINT_REAL) {
+ euid = ruid;
+ egid = rgid;
}
- /* Print full info like GNU id */
- /* bb_getpwuid doesn't exit on failure here */
- status = printf_full(uid, bb_getpwuid(NULL, uid, 0), 'u');
- putchar(' ');
- /* bb_getgrgid doesn't exit on failure here */
- status |= printf_full(gid, bb_getgrgid(NULL, gid, 0), 'g');
-
+ if (opt & JUST_USER)
+ status |= print_user(euid, NULL);
+ else if (opt & JUST_GROUP)
+ status |= print_group(egid, NULL);
#if ENABLE_SELINUX
- if (is_selinux_enabled()) {
- security_context_t mysid;
- const char *context;
-
- context = "unknown";
- getcon(&mysid);
- if (mysid) {
- context = alloca(strlen(mysid) + 1);
- strcpy((char*)context, mysid);
- freecon(mysid);
+ 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" : "");
}
- printf(" context=%s", context);
+ fputs(scontext, stdout);
}
+ /* freecon(NULL) seems to be harmless */
+ if (ENABLE_FEATURE_CLEAN_UP)
+ freecon(scontext);
#endif
-
- putchar('\n');
+ bb_putchar('\n');
fflush_stdout_and_exit(status);
}
projects / oweals / busybox.git / blobdiff