OpenBSD-4.6/usr.bin/id/id.c
/* $OpenBSD: id.c,v 1.17 2004/11/16 13:51:35 jmc Exp $ */
/*-
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
static char copyright[] =
"@(#) Copyright (c) 1991, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
/*static char sccsid[] = "@(#)id.c 8.3 (Berkeley) 4/28/95";*/
static char rcsid[] = "$OpenBSD: id.c,v 1.17 2004/11/16 13:51:35 jmc Exp $";
#endif /* not lint */
#include <sys/param.h>
#include <errno.h>
#include <grp.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <err.h>
void current(void);
void pretty(struct passwd *);
void group(struct passwd *, int);
void usage(void);
void user(struct passwd *);
struct passwd *
who(char *);
int
main(int argc, char *argv[])
{
struct group *gr;
struct passwd *pw;
int Gflag, ch, gflag, nflag, pflag, rflag, uflag;
uid_t uid;
gid_t gid;
Gflag = gflag = nflag = pflag = rflag = uflag = 0;
while ((ch = getopt(argc, argv, "Ggnpru")) != -1)
switch(ch) {
case 'G':
Gflag = 1;
break;
case 'g':
gflag = 1;
break;
case 'n':
nflag = 1;
break;
case 'p':
pflag = 1;
break;
case 'r':
rflag = 1;
break;
case 'u':
uflag = 1;
break;
case '?':
default:
usage();
}
argc -= optind;
argv += optind;
switch(Gflag + gflag + pflag + uflag) {
case 1:
break;
case 0:
if (!nflag && !rflag)
break;
/* FALLTHROUGH */
default:
usage();
}
pw = *argv ? who(*argv) : NULL;
if (gflag) {
gid = pw ? pw->pw_gid : rflag ? getgid() : getegid();
if (nflag && (gr = getgrgid(gid)))
(void)printf("%s\n", gr->gr_name);
else
(void)printf("%u\n", gid);
exit(0);
}
if (uflag) {
uid = pw ? pw->pw_uid : rflag ? getuid() : geteuid();
if (nflag && (pw = getpwuid(uid)))
(void)printf("%s\n", pw->pw_name);
else
(void)printf("%u\n", uid);
exit(0);
}
if (Gflag) {
group(pw, nflag);
exit(0);
}
if (pflag) {
pretty(pw);
exit(0);
}
if (pw)
user(pw);
else
current();
exit(0);
}
void
pretty(struct passwd *pw)
{
struct group *gr;
uid_t eid, rid;
char *login;
if (pw) {
(void)printf("uid\t%s\n", pw->pw_name);
(void)printf("groups\t");
group(pw, 1);
} else {
if ((login = getlogin()) == NULL)
err(1, "getlogin");
pw = getpwuid(rid = getuid());
if (pw == NULL || strcmp(login, pw->pw_name))
(void)printf("login\t%s\n", login);
if (pw)
(void)printf("uid\t%s\n", pw->pw_name);
else
(void)printf("uid\t%u\n", rid);
if ((eid = geteuid()) != rid) {
if ((pw = getpwuid(eid)))
(void)printf("euid\t%s\n", pw->pw_name);
else
(void)printf("euid\t%u\n", eid);
}
if ((rid = getgid()) != (eid = getegid())) {
if ((gr = getgrgid(rid)))
(void)printf("rgid\t%s\n", gr->gr_name);
else
(void)printf("rgid\t%u\n", rid);
}
(void)printf("groups\t");
group(NULL, 1);
}
}
void
current(void)
{
struct group *gr;
struct passwd *pw;
int cnt, ngroups;
uid_t uid, euid;
gid_t groups[NGROUPS], gid, egid, lastgid;
char *fmt;
uid = getuid();
(void)printf("uid=%u", uid);
if ((pw = getpwuid(uid)))
(void)printf("(%s)", pw->pw_name);
if ((euid = geteuid()) != uid) {
(void)printf(" euid=%u", euid);
if ((pw = getpwuid(euid)))
(void)printf("(%s)", pw->pw_name);
}
gid = getgid();
(void)printf(" gid=%u", gid);
if ((gr = getgrgid(gid)))
(void)printf("(%s)", gr->gr_name);
if ((egid = getegid()) != gid) {
(void)printf(" egid=%u", egid);
if ((gr = getgrgid(egid)))
(void)printf("(%s)", gr->gr_name);
}
if ((ngroups = getgroups(NGROUPS, groups))) {
for (fmt = " groups=%u", lastgid = (gid_t)-1, cnt = 0; cnt < ngroups;
fmt = ", %u", lastgid = gid) {
gid = groups[cnt++];
if (lastgid == gid)
continue;
(void)printf(fmt, gid);
if ((gr = getgrgid(gid)))
(void)printf("(%s)", gr->gr_name);
}
}
(void)printf("\n");
}
void
user(struct passwd *pw)
{
gid_t gid, groups[NGROUPS + 1];
int cnt, ngroups;
uid_t uid;
struct group *gr;
char *fmt;
uid = pw->pw_uid;
(void)printf("uid=%u(%s)", uid, pw->pw_name);
(void)printf(" gid=%u", pw->pw_gid);
if ((gr = getgrgid(pw->pw_gid)))
(void)printf("(%s)", gr->gr_name);
ngroups = NGROUPS + 1;
(void) getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups);
fmt = " groups=%u";
for (cnt = 0; cnt < ngroups;) {
gid = groups[cnt];
(void)printf(fmt, gid);
fmt = ", %u";
if ((gr = getgrgid(gid)))
(void)printf("(%s)", gr->gr_name);
/* Skip same gid entries. */
while (++cnt < ngroups && gid == groups[cnt]);
}
(void)printf("\n");
}
void
group(struct passwd *pw, int nflag)
{
int cnt, ngroups;
gid_t gid, groups[NGROUPS + 1];
struct group *gr;
char *fmt;
if (pw) {
ngroups = NGROUPS + 1;
(void) getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups);
} else {
groups[0] = getgid();
ngroups = getgroups(NGROUPS, groups + 1) + 1;
}
fmt = nflag ? "%s" : "%u";
for (cnt = 0; cnt < ngroups;) {
gid = groups[cnt];
if (nflag) {
if ((gr = getgrgid(gid)))
(void)printf(fmt, gr->gr_name);
else
(void)printf(*fmt == ' ' ? " %u" : "%u",
gid);
fmt = " %s";
} else {
(void)printf(fmt, gid);
fmt = " %u";
}
/* Skip same gid entries. */
while (++cnt < ngroups && gid == groups[cnt]);
}
(void)printf("\n");
}
struct passwd *
who(char *u)
{
struct passwd *pw;
uid_t uid;
const char *errstr;
/*
* Translate user argument into a pw pointer. First, try to
* get it as specified. If that fails, try it as a number.
*/
if ((pw = getpwnam(u)))
return(pw);
uid = strtonum(u, 0, UID_MAX, &errstr);
if (!errstr && (pw = getpwuid(uid)))
return(pw);
errx(1, "%s: No such user", u);
/* NOTREACHED */
}
void
usage(void)
{
(void)fprintf(stderr, "usage: id [user]\n"
" id -G [-n] [user]\n"
" id -g [-nr] [user]\n"
" id -p [user]\n"
" id -u [-nr] [user]\n");
exit(1);
}