| /* vi: set sw=4 ts=4: */ |
| /* |
| * 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 source tree. |
| */ |
| /* 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" |
| //config: default y |
| //config: help |
| //config: id displays the current user and group ID names. |
| //config: |
| //config:config GROUPS |
| //config: bool "groups" |
| //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" |
| |
| //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" |
| |
| #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 |
| 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 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); |
| } |
| |
| /* 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; |
| } |
| |
| *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) 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 |
| |
| 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_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")); |
| } |
| |
| 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(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_error_msg_and_die("can't get groups"); |
| 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); |
| } |