usr.bin/id/id.c

   1 /*-
   2  * Copyright (c) 1991, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#) Copyright (c) 1991, 1993 The Regents of the University of California.  All rights reserved.
  30  * @(#)id.c     8.2 (Berkeley) 2/16/94
  31  * $FreeBSD: src/usr.bin/id/id.c,v 1.12.2.3 2001/12/20 12:09:03 ru Exp $
  32  */
  33
  34 #include <sys/param.h>
  35
  36 #include <err.h>
  37 #include <grp.h>
  38 #include <pwd.h>
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42 #include <unistd.h>
  43
  44 static void     current(void);
  45 static void     pline(struct passwd *);
  46 static void     pretty(struct passwd *);
  47 static void     group(struct passwd *, int);
  48 static void     usage(void);
  49 static void     user(struct passwd *);
  50 static struct passwd *
  51                 who(char *);
  52
  53 int isgroups, iswhoami;
  54
  55 int
  56 main(int argc, char **argv)
  57 {
  58         struct group *gr;
  59         struct passwd *pw;
  60         int Gflag, Pflag, ch, gflag, id, nflag, pflag, rflag, uflag;
  61         const char *myname;
  62
  63         Gflag = Pflag = gflag = nflag = pflag = rflag = uflag = 0;
  64
  65         myname = strrchr(argv[0], '/');
  66         myname = (myname != NULL) ? myname + 1 : argv[0];
  67         if (strcmp(myname, "groups") == 0) {
  68                 isgroups = 1;
  69                 Gflag = nflag = 1;
  70         }
  71         else if (strcmp(myname, "whoami") == 0) {
  72                 iswhoami = 1;
  73                 uflag = nflag = 1;
  74         }
  75
  76         while ((ch = getopt(argc, argv,
  77             (isgroups || iswhoami) ? "" : "PGgnpru")) != -1)
  78                 switch(ch) {
  79                 case 'G':
  80                         Gflag = 1;
  81                         break;
  82                 case 'P':
  83                         Pflag = 1;
  84                         break;
  85                 case 'g':
  86                         gflag = 1;
  87                         break;
  88                 case 'n':
  89                         nflag = 1;
  90                         break;
  91                 case 'p':
  92                         pflag = 1;
  93                         break;
  94                 case 'r':
  95                         rflag = 1;
  96                         break;
  97                 case 'u':
  98                         uflag = 1;
  99                         break;
 100                 case '?':
 101                 default:
 102                         usage();
 103                 }
 104         argc -= optind;
 105         argv += optind;
 106
 107         if (iswhoami && argc > 0)
 108                 usage();
 109
 110         switch(Gflag + Pflag + gflag + pflag + uflag) {
 111         case 1:
 112                 break;
 113         case 0:
 114                 if (!nflag && !rflag)
 115                         break;
 116                 /* FALLTHROUGH */
 117         default:
 118                 usage();
 119         }
 120
 121         pw = *argv ? who(*argv) : NULL;
 122
 123         if (gflag) {
 124                 id = pw ? pw->pw_gid : rflag ? getgid() : getegid();
 125                 if (nflag && (gr = getgrgid(id)))
 126                         printf("%s\n", gr->gr_name);
 127                 else
 128                         printf("%u\n", id);
 129                 exit(0);
 130         }
 131
 132         if (uflag) {
 133                 id = pw ? pw->pw_uid : rflag ? getuid() : geteuid();
 134                 if (nflag && (pw = getpwuid(id)))
 135                         printf("%s\n", pw->pw_name);
 136                 else
 137                         printf("%u\n", id);
 138                 exit(0);
 139         }
 140
 141         if (Gflag) {
 142                 group(pw, nflag);
 143                 exit(0);
 144         }
 145
 146         if (Pflag) {
 147                 pline(pw);
 148                 exit(0);
 149         }
 150
 151         if (pflag) {
 152                 pretty(pw);
 153                 exit(0);
 154         }
 155
 156         if (pw)
 157                 user(pw);
 158         else
 159                 current();
 160         exit(0);
 161 }
 162
 163 static void
 164 pretty(struct passwd *pw)
 165 {
 166         struct group *gr;
 167         u_int eid, rid;
 168         char *login;
 169
 170         if (pw) {
 171                 printf("uid\t%s\n", pw->pw_name);
 172                 printf("groups\t");
 173                 group(pw, 1);
 174         } else {
 175                 if ((login = getlogin()) == NULL)
 176                         err(1, "getlogin");
 177
 178                 pw = getpwuid(rid = getuid());
 179                 if (pw == NULL || strcmp(login, pw->pw_name))
 180                         printf("login\t%s\n", login);
 181                 if (pw)
 182                         printf("uid\t%s\n", pw->pw_name);
 183                 else
 184                         printf("uid\t%u\n", rid);
 185
 186                 if ((eid = geteuid()) != rid) {
 187                         if ((pw = getpwuid(eid)))
 188                                 printf("euid\t%s\n", pw->pw_name);
 189                         else
 190                                 printf("euid\t%u\n", eid);
 191                 }
 192                 if ((rid = getgid()) != (eid = getegid())) {
 193                         if ((gr = getgrgid(rid)))
 194                                 printf("rgid\t%s\n", gr->gr_name);
 195                         else
 196                                 printf("rgid\t%u\n", rid);
 197                 }
 198                 printf("groups\t");
 199                 group(NULL, 1);
 200         }
 201 }
 202
 203 static void
 204 current(void)
 205 {
 206         struct group *gr;
 207         struct passwd *pw;
 208         int cnt, id, eid, lastid, ngroups;
 209         gid_t groups[NGROUPS];
 210         const char *fmt;
 211
 212         id = getuid();
 213         printf("uid=%u", id);
 214         if ((pw = getpwuid(id)))
 215                 printf("(%s)", pw->pw_name);
 216         if ((eid = geteuid()) != id) {
 217                 printf(" euid=%u", eid);
 218                 if ((pw = getpwuid(eid)))
 219                         printf("(%s)", pw->pw_name);
 220         }
 221         id = getgid();
 222         printf(" gid=%u", id);
 223         if ((gr = getgrgid(id)))
 224                 printf("(%s)", gr->gr_name);
 225         if ((eid = getegid()) != id) {
 226                 printf(" egid=%u", eid);
 227                 if ((gr = getgrgid(eid)))
 228                         printf("(%s)", gr->gr_name);
 229         }
 230         if ((ngroups = getgroups(NGROUPS, groups))) {
 231                 for (fmt = " groups=%u", lastid = -1, cnt = 0; cnt < ngroups;
 232                     fmt = ", %u", lastid = id) {
 233                         id = groups[cnt++];
 234                         if (lastid == id)
 235                                 continue;
 236                         printf(fmt, id);
 237                         if ((gr = getgrgid(id)))
 238                                 printf("(%s)", gr->gr_name);
 239                 }
 240         }
 241         printf("\n");
 242 }
 243
 244 static void
 245 user(struct passwd *pw)
 246 {
 247         struct group *gr;
 248         const char *fmt;
 249         int cnt, ngroups;
 250         gid_t gid, lastgid, groups[NGROUPS + 1];
 251
 252         printf("uid=%u(%s)", pw->pw_uid, pw->pw_name);
 253         gid = pw->pw_gid;
 254         printf(" gid=%u", gid);
 255         if ((gr = getgrgid(gid)))
 256                 printf("(%s)", gr->gr_name);
 257         ngroups = NGROUPS + 1;
 258         getgrouplist(pw->pw_name, gid, groups, &ngroups);
 259         fmt = " groups=%u";
 260         for (lastgid = -1, cnt = 0; cnt < ngroups; ++cnt) {
 261                 if (lastgid == (gid = groups[cnt]))
 262                         continue;
 263                 printf(fmt, gid);
 264                 fmt = ", %u";
 265                 if ((gr = getgrgid(gid)))
 266                         printf("(%s)", gr->gr_name);
 267                 lastgid = gid;
 268         }
 269         printf("\n");
 270 }
 271
 272 static void
 273 group(struct passwd *pw, int nflag)
 274 {
 275         struct group *gr;
 276         int cnt, id, lastid, ngroups;
 277         gid_t groups[NGROUPS + 1];
 278         const char *fmt;
 279
 280         if (pw) {
 281                 ngroups = NGROUPS + 1;
 282                 getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups);
 283         } else {
 284                 groups[0] = getgid();
 285                 ngroups = getgroups(NGROUPS, groups + 1) + 1;
 286         }
 287         fmt = nflag ? "%s" : "%u";
 288         for (lastid = -1, cnt = 0; cnt < ngroups; ++cnt) {
 289                 if (lastid == (id = groups[cnt]))
 290                         continue;
 291                 if (nflag) {
 292                         if ((gr = getgrgid(id)))
 293                                 printf(fmt, gr->gr_name);
 294                         else
 295                                 printf(*fmt == ' ' ? " %u" : "%u",
 296                                     id);
 297                         fmt = " %s";
 298                 } else {
 299                         printf(fmt, id);
 300                         fmt = " %u";
 301                 }
 302                 lastid = id;
 303         }
 304         printf("\n");
 305 }
 306
 307 static struct passwd *
 308 who(char *u)
 309 {
 310         struct passwd *pw;
 311         long id;
 312         char *ep;
 313
 314         /*
 315          * Translate user argument into a pw pointer.  First, try to
 316          * get it as specified.  If that fails, try it as a number.
 317          */
 318         if ((pw = getpwnam(u)))
 319                 return(pw);
 320         id = strtol(u, &ep, 10);
 321         if (*u && !*ep && (pw = getpwuid(id)))
 322                 return(pw);
 323         errx(1, "%s: no such user", u);
 324         /* NOTREACHED */
 325 }
 326
 327 static void
 328 pline(struct passwd *pw)
 329 {
 330         u_int rid;
 331
 332         if (!pw) {
 333                 if ((pw = getpwuid(rid = getuid())) == NULL)
 334                         err(1, "getpwuid");
 335         }
 336
 337         printf("%s:%s:%d:%d:%s:%ld:%ld:%s:%s:%s\n", pw->pw_name,
 338                         pw->pw_passwd, pw->pw_uid, pw->pw_gid, pw->pw_class,
 339                         (long)pw->pw_change, (long)pw->pw_expire, pw->pw_gecos,
 340                         pw->pw_dir, pw->pw_shell);
 341 }
 342
 343
 344 static void
 345 usage(void)
 346 {
 347
 348         if (isgroups)
 349                 fprintf(stderr, "usage: groups [user]\n");
 350         else if (iswhoami)
 351                 fprintf(stderr, "usage: whoami\n");
 352         else
 353                 fprintf(stderr, "%s\n%s\n%s\n%s\n%s\n%s\n",
 354                     "usage: id [user]",
 355                     "       id -G [-n] [user]",
 356                     "       id -P [user]",
 357                     "       id -g [-nr] [user]",
 358                     "       id -p [user]",
 359                     "       id -u [-nr] [user]");
 360         exit(1);
 361 }