/* * 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) *//*   Copyright (C) 1999-2009 Free Software Foundation, Inc.   This file is part of GNU Bash.   Bash is free software: you can redistribute it and/or modify   it under the terms of the GNU General Public License as published by   the Free Software Foundation, either version 3 of the License, or   (at your option) any later version.   Bash is distributed in the hope that it will be useful,   but WITHOUT ANY WARRANTY; without even the implied warranty of   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the   GNU General Public License for more details.   You should have received a copy of the GNU General Public License   along with Bash.  If not, see <http://www.gnu.org/licenses/>.*/#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 ();#endifextern 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 ();intid_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 intinituser (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 intid_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 intid_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 intid_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 intid_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[] = {	"Display information about user."	"",	"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};