busybox/coreutils/id.c

131 lines
3.2 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Mini id implementation for busybox
*
* Copyright (C) 2000 by Randolph Chung <tausq@debian.org>
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
/* 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.
* -Z option support: by Yuichi Nakamura <ynakam@hitachisoft.jp>
*/
#include "busybox.h"
#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#define PRINT_REAL 1
#define NAME_NOT_NUMBER 2
#define JUST_USER 4
#define JUST_GROUP 8
#if ENABLE_SELINUX
#define JUST_CONTEXT 16
#endif
static short printf_full(unsigned int id, const char *arg, const char prefix)
{
const char *fmt = "%cid=%u";
short status = EXIT_FAILURE;
if (arg) {
fmt = "%cid=%u(%s)";
status = EXIT_SUCCESS;
}
printf(fmt, prefix, id, arg);
return status;
}
int id_main(int argc, char **argv);
int id_main(int argc, char **argv)
{
struct passwd *p;
uid_t uid;
gid_t gid;
unsigned long flags;
short status;
#if ENABLE_SELINUX
security_context_t scontext;
#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 (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 */
}
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 ));
} else {
if (flags & JUST_USER) {
printf("%u\n", uid);
}
if (flags & JUST_GROUP) {
printf("%u\n", gid);
}
}
#if ENABLE_SELINUX
if (flags & JUST_CONTEXT) {
selinux_or_die();
if (argc - optind == 1) {
bb_error_msg_and_die("can't print security context when user specified");
}
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);
}
/* 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 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);
}
printf(" context=%s", context);
}
#endif
putchar('\n');
fflush_stdout_and_exit(status);
}