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 static 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) ? "" : "PGagnpru")) != -1)
  78                 switch(ch) {
  79                 case 'G':
  80                         Gflag = 1;
  81                         break;
  82                 case 'P':
  83                         Pflag = 1;
  84                         break;
  85                 case 'a':
  86                         break;
  87                 case 'g':
  88                         gflag = 1;
  89                         break;
  90                 case 'n':
  91                         nflag = 1;
  92                         break;
  93                 case 'p':
  94                         pflag = 1;
  95                         break;
  96                 case 'r':
  97                         rflag = 1;
  98                         break;
  99                 case 'u':
 100                         uflag = 1;
 101                         break;
 102                 case '?':
 103                 default:
 104                         usage();
 105                 }
 106         argc -= optind;
 107         argv += optind;
 108
 109         if (iswhoami && argc > 0)
 110                 usage();
 111
 112         switch(Gflag + Pflag + gflag + pflag + uflag) {
 113         case 1:
 114                 break;
 115         case 0:
 116                 if (!nflag && !rflag)
 117                         break;
 118                 /* FALLTHROUGH */
 119         default:
 120                 usage();
 121         }
 122
 123         pw = *argv ? who(*argv) : NULL;
 124
 125         if (gflag) {
 126                 id = pw ? pw->pw_gid : rflag ? getgid() : getegid();
 127                 if (nflag && (gr = getgrgid(id)))
 128                         printf("%s\n", gr->gr_name);
 129                 else
 130                         printf("%u\n", id);
 131                 exit(0);
 132         }
 133
 134         if (uflag) {
 135                 id = pw ? pw->pw_uid : rflag ? getuid() : geteuid();
 136                 if (nflag && (pw = getpwuid(id)))
 137                         printf("%s\n", pw->pw_name);
 138                 else
 139                         printf("%u\n", id);
 140                 exit(0);
 141         }
 142
 143         if (Gflag) {
 144                 group(pw, nflag);
 145                 exit(0);
 146         }
 147
 148         if (Pflag) {
 149                 pline(pw);
 150                 exit(0);
 151         }
 152
 153         if (pflag) {
 154                 pretty(pw);
 155                 exit(0);
 156         }
 157
 158         if (pw)
 159                 user(pw);
 160         else
 161                 current();
 162         exit(0);
 163 }
 164
 165 static void
 166 pretty(struct passwd *pw)
 167 {
 168         struct group *gr;
 169         u_int eid, rid;
 170         char *login;
 171
 172         if (pw) {
 173                 printf("uid\t%s\n", pw->pw_name);
 174                 printf("groups\t");
 175                 group(pw, 1);
 176         } else {
 177                 if ((login = getlogin()) == NULL)
 178                         err(1, "getlogin");
 179
 180                 pw = getpwuid(rid = getuid());
 181                 if (pw == NULL || strcmp(login, pw->pw_name))
 182                         printf("login\t%s\n", login);
 183                 if (pw)
 184                         printf("uid\t%s\n", pw->pw_name);
 185                 else
 186                         printf("uid\t%u\n", rid);
 187
 188                 if ((eid = geteuid()) != rid) {
 189                         if ((pw = getpwuid(eid)))
 190                                 printf("euid\t%s\n", pw->pw_name);
 191                         else
 192                                 printf("euid\t%u\n", eid);
 193                 }
 194                 if ((rid = getgid()) != (eid = getegid())) {
 195                         if ((gr = getgrgid(rid)))
 196                                 printf("rgid\t%s\n", gr->gr_name);
 197                         else
 198                                 printf("rgid\t%u\n", rid);
 199                 }
 200                 printf("groups\t");
 201                 group(NULL, 1);
 202         }
 203 }
 204
 205 static void
 206 current(void)
 207 {
 208         struct group *gr;
 209         struct passwd *pw;
 210         int cnt, id, eid, lastid, ngroups;
 211         gid_t groups[NGROUPS];
 212         const char *fmt;
 213
 214         id = getuid();
 215         printf("uid=%u", id);
 216         if ((pw = getpwuid(id)))
 217                 printf("(%s)", pw->pw_name);
 218         if ((eid = geteuid()) != id) {
 219                 printf(" euid=%u", eid);
 220                 if ((pw = getpwuid(eid)))
 221                         printf("(%s)", pw->pw_name);
 222         }
 223         id = getgid();
 224         printf(" gid=%u", id);
 225         if ((gr = getgrgid(id)))
 226                 printf("(%s)", gr->gr_name);
 227         if ((eid = getegid()) != id) {
 228                 printf(" egid=%u", eid);
 229                 if ((gr = getgrgid(eid)))
 230                         printf("(%s)", gr->gr_name);
 231         }
 232         if ((ngroups = getgroups(NGROUPS, groups))) {
 233                 for (fmt = " groups=%u", lastid = -1, cnt = 0; cnt < ngroups;
 234                     fmt = ", %u", lastid = id) {
 235                         id = groups[cnt++];
 236                         if (lastid == id)
 237                                 continue;
 238                         printf(fmt, id);
 239                         if ((gr = getgrgid(id)))
 240                                 printf("(%s)", gr->gr_name);
 241                 }
 242         }
 243         printf("\n");
 244 }
 245
 246 static void
 247 user(struct passwd *pw)
 248 {
 249         struct group *gr;
 250         const char *fmt;
 251         int cnt, ngroups;
 252         gid_t gid, lastgid, groups[NGROUPS + 1];
 253
 254         printf("uid=%u(%s)", pw->pw_uid, pw->pw_name);
 255         gid = pw->pw_gid;
 256         printf(" gid=%u", gid);
 257         if ((gr = getgrgid(gid)))
 258                 printf("(%s)", gr->gr_name);
 259         ngroups = NGROUPS + 1;
 260         getgrouplist(pw->pw_name, gid, groups, &ngroups);
 261         fmt = " groups=%u";
 262         for (lastgid = -1, cnt = 0; cnt < ngroups; ++cnt) {
 263                 if (lastgid == (gid = groups[cnt]))
 264                         continue;
 265                 printf(fmt, gid);
 266                 fmt = ", %u";
 267                 if ((gr = getgrgid(gid)))
 268                         printf("(%s)", gr->gr_name);
 269                 lastgid = gid;
 270         }
 271         printf("\n");
 272 }
 273
 274 static void
 275 group(struct passwd *pw, int nflag)
 276 {
 277         struct group *gr;
 278         int cnt, id, lastid, ngroups;
 279         gid_t groups[NGROUPS + 1];
 280         const char *fmt;
 281
 282         if (pw) {
 283                 ngroups = NGROUPS + 1;
 284                 getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups);
 285         } else {
 286                 groups[0] = getgid();
 287                 ngroups = getgroups(NGROUPS, groups + 1) + 1;
 288         }
 289         fmt = nflag ? "%s" : "%u";
 290         for (lastid = -1, cnt = 0; cnt < ngroups; ++cnt) {
 291                 if (lastid == (id = groups[cnt]))
 292                         continue;
 293                 if (nflag) {
 294                         if ((gr = getgrgid(id)))
 295                                 printf(fmt, gr->gr_name);
 296                         else
 297                                 printf(*fmt == ' ' ? " %u" : "%u",
 298                                     id);
 299                         fmt = " %s";
 300                 } else {
 301                         printf(fmt, id);
 302                         fmt = " %u";
 303                 }
 304                 lastid = id;
 305         }
 306         printf("\n");
 307 }
 308
 309 static struct passwd *
 310 who(char *u)
 311 {
 312         struct passwd *pw;
 313         long id;
 314         char *ep;
 315
 316         /*
 317          * Translate user argument into a pw pointer.  First, try to
 318          * get it as specified.  If that fails, try it as a number.
 319          */
 320         if ((pw = getpwnam(u)))
 321                 return(pw);
 322         id = strtol(u, &ep, 10);
 323         if (*u && !*ep && (pw = getpwuid(id)))
 324                 return(pw);
 325         errx(1, "%s: no such user", u);
 326         /* NOTREACHED */
 327 }
 328
 329 static void
 330 pline(struct passwd *pw)
 331 {
 332         u_int rid;
 333
 334         if (!pw) {
 335                 if ((pw = getpwuid(rid = getuid())) == NULL)
 336                         err(1, "getpwuid");
 337         }
 338
 339         printf("%s:%s:%d:%d:%s:%ld:%ld:%s:%s:%s\n", pw->pw_name,
 340                         pw->pw_passwd, pw->pw_uid, pw->pw_gid, pw->pw_class,
 341                         (long)pw->pw_change, (long)pw->pw_expire, pw->pw_gecos,
 342                         pw->pw_dir, pw->pw_shell);
 343 }
 344
 345
 346 static void
 347 usage(void)
 348 {
 349
 350         if (isgroups)
 351                 fprintf(stderr, "usage: groups [user]\n");
 352         else if (iswhoami)
 353                 fprintf(stderr, "usage: whoami\n");
 354         else
 355                 fprintf(stderr, "%s\n%s\n%s\n%s\n%s\n%s\n",
 356                     "usage: id [user]",
 357                     "       id -G [-n] [user]",
 358                     "       id -P [user]",
 359                     "       id -g [-nr] [user]",
 360                     "       id -p [user]",
 361                     "       id -u [-nr] [user]");
 362         exit(1);
 363 }