Viewing file:  id.c (5.51 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
/*
* id - POSIX.2 user identity
*
* (INCOMPLETE -- supplementary groups for other users not yet done)
*
* usage: id [-Ggu] [-nr] [user]
*
* The default output format looks something like:
* uid=xxx(chet) gid=xx groups=aa(aname), bb(bname), cc(cname)
*/
#include <config.h>
#include <stdio.h>
#include "bashtypes.h"
#include <pwd.h>
#include <grp.h>
#include "bashansi.h"
#ifdef HAVE_LIMITS_H
# include <limits.h>
#else
# include <sys/param.h>
#endif
#if !defined (HAVE_GETPW_DECLS)
extern struct passwd *getpwuid ();
#endif
extern struct group *getgrgid ();
#include "shell.h"
#include "builtins.h"
#include "stdc.h"
#include "common.h"
#include "bashgetopt.h"
#define ID_ALLGROUPS 0x001 /* -G */
#define ID_GIDONLY 0x002 /* -g */
#define ID_USENAME 0x004 /* -n */
#define ID_USEREAL 0x008 /* -r */
#define ID_USERONLY 0x010 /* -u */
#define ID_FLAGSET(s) ((id_flags & (s)) != 0)
static int id_flags;
static uid_t ruid, euid;
static gid_t rgid, egid;
static char *id_user;
static int inituser ();
static int id_pruser ();
static int id_prgrp ();
static int id_prgroups ();
static int id_prall ();
int
id_builtin (list)
WORD_LIST *list;
{
int opt;
char *user;
id_flags = 0;
reset_internal_getopt ();
while ((opt = internal_getopt (list, "Ggnru")) != -1)
{
switch (opt)
{
case 'G': id_flags |= ID_ALLGROUPS; break;
case 'g': id_flags |= ID_GIDONLY; break;
case 'n': id_flags |= ID_USENAME; break;
case 'r': id_flags |= ID_USEREAL; break;
case 'u': id_flags |= ID_USERONLY; break;
default:
builtin_usage ();
return (EX_USAGE);
}
}
list = loptend;
user = list ? list->word->word : (char *)NULL;
/* Check for some invalid option combinations */
opt = ID_FLAGSET (ID_ALLGROUPS) + ID_FLAGSET (ID_GIDONLY) + ID_FLAGSET (ID_USERONLY);
if (opt > 1 || (opt == 0 && ((id_flags & (ID_USEREAL|ID_USENAME)) != 0)))
{
builtin_usage ();
return (EX_USAGE);
}
if (list && list->next)
{
builtin_usage ();
return (EX_USAGE);
}
if (inituser (user) < 0)
return (EXECUTION_FAILURE);
opt = 0;
if (id_flags & ID_USERONLY)
opt += id_pruser ((id_flags & ID_USEREAL) ? ruid : euid);
else if (id_flags & ID_GIDONLY)
opt += id_prgrp ((id_flags & ID_USEREAL) ? rgid : egid);
else if (id_flags & ID_ALLGROUPS)
opt += id_prgroups (user);
else
opt += id_prall (user);
putchar ('\n');
fflush (stdout);
return (opt == 0 ? EXECUTION_SUCCESS : EXECUTION_FAILURE);
}
static int
inituser (uname)
char *uname;
{
struct passwd *pwd;
if (uname)
{
pwd = getpwnam (uname);
if (pwd == 0)
{
builtin_error ("%s: no such user", uname);
return -1;
}
ruid = euid = pwd->pw_uid;
rgid = egid = pwd->pw_gid;
}
else
{
ruid = current_user.uid;
euid = current_user.euid;
rgid = current_user.gid;
egid = current_user.egid;
}
return 0;
}
/* Print the name or value of user ID UID. */
static int
id_pruser (uid)
int uid;
{
struct passwd *pwd = NULL;
int r;
r = 0;
if (id_flags & ID_USENAME)
{
pwd = getpwuid (uid);
if (pwd == NULL)
r = 1;
}
if (pwd)
printf ("%s", pwd->pw_name);
else
printf ("%u", (unsigned) uid);
return r;
}
/* Print the name or value of group ID GID. */
static int
id_prgrp (gid)
int gid;
{
struct group *grp = NULL;
int r;
r = 0;
if (id_flags & ID_USENAME)
{
grp = getgrgid (gid);
if (grp == NULL)
r = 1;
}
if (grp)
printf ("%s", grp->gr_name);
else
printf ("%u", (unsigned) gid);
return r;
}
static int
id_prgroups (uname)
char *uname;
{
int *glist, ng, i, r;
r = 0;
id_prgrp (rgid);
if (egid != rgid)
{
putchar (' ');
id_prgrp (egid);
}
if (uname)
{
builtin_error ("supplementary groups for other users not yet implemented");
glist = (int *)NULL;
ng = 0;
r = 1;
}
else
glist = get_group_array (&ng);
for (i = 0; i < ng; i++)
if (glist[i] != rgid && glist[i] != egid)
{
putchar (' ');
id_prgrp (glist[i]);
}
return r;
}
static int
id_prall (uname)
char *uname;
{
int r, i, ng, *glist;
struct passwd *pwd;
struct group *grp;
r = 0;
printf ("uid=%u", (unsigned) ruid);
pwd = getpwuid (ruid);
if (pwd == NULL)
r = 1;
else
printf ("(%s)", pwd->pw_name);
printf (" gid=%u", (unsigned) rgid);
grp = getgrgid (rgid);
if (grp == NULL)
r = 1;
else
printf ("(%s)", grp->gr_name);
if (euid != ruid)
{
printf (" euid=%u", (unsigned) euid);
pwd = getpwuid (euid);
if (pwd == NULL)
r = 1;
else
printf ("(%s)", pwd->pw_name);
}
if (egid != rgid)
{
printf (" egid=%u", (unsigned) egid);
grp = getgrgid (egid);
if (grp == NULL)
r = 1;
else
printf ("(%s)", grp->gr_name);
}
if (uname)
{
builtin_error ("supplementary groups for other users not yet implemented");
glist = (int *)NULL;
ng = 0;
r = 1;
}
else
glist = get_group_array (&ng);
if (ng > 0)
printf (" groups=");
for (i = 0; i < ng; i++)
{
if (i > 0)
printf (", ");
printf ("%u", (unsigned) glist[i]);
grp = getgrgid (glist[i]);
if (grp == NULL)
r = 1;
else
printf ("(%s)", grp->gr_name);
}
return r;
}
char *id_doc[] = {
"return information about user identity",
(char *)NULL
};
struct builtin id_struct = {
"id",
id_builtin,
BUILTIN_ENABLED,
id_doc,
"id [user]\n\tid -G [-n] [user]\n\tid -g [-nr] [user]\n\tid -u [-nr] [user]",
0
};
|