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. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #ifndef lint
  35 static const char copyright[] =
  36 "@(#) Copyright (c) 1991, 1993\n\
  37         The Regents of the University of California.  All rights reserved.\n";
  38 #endif /* not lint */
  39
  40 #ifndef lint
  41 #if 0
  42 static char sccsid[] = "@(#)id.c        8.2 (Berkeley) 2/16/94";
  43 #endif
  44 #endif /* not lint */
  45 #include <sys/cdefs.h>
  46 __RCSID("$FreeBSD: src/usr.bin/id/id.c,v 1.19 2002/09/04 23:29:02 dwmalone Exp $");
  47
  48 #include <sys/param.h>
  49
  50 #include <err.h>
  51 #include <grp.h>
  52 #include <pwd.h>
  53 #include <stdio.h>
  54 #include <stdlib.h>
  55 #include <string.h>
  56 #include <unistd.h>
  57
  58 void    current(void);
  59 void    pline(struct passwd *);
  60 void    pretty(struct passwd *);
  61 void    group(struct passwd *, int);
  62 void    usage(void);
  63 void    user(struct passwd *);
  64 struct passwd *
  65         who(char *);
  66
  67 int isgroups, iswhoami;
  68
  69 int
  70 main(int argc, char *argv[])
  71 {
  72         struct group *gr;
  73         struct passwd *pw;
  74         int Gflag, Pflag, ch, gflag, id, nflag, pflag, rflag, uflag;
  75         const char *myname;
  76
  77         Gflag = Pflag = gflag = nflag = pflag = rflag = uflag = 0;
  78
  79         myname = strrchr(argv[0], '/');
  80         myname = (myname != NULL) ? myname + 1 : argv[0];
  81         if (strcmp(myname, "groups") == 0) {
  82                 isgroups = 1;
  83                 Gflag = nflag = 1;
  84         }
  85         else if (strcmp(myname, "whoami") == 0) {
  86                 iswhoami = 1;
  87                 uflag = nflag = 1;
  88         }
  89
  90         while ((ch = getopt(argc, argv,
  91             (isgroups || iswhoami) ? "" : "PGgnpru")) != -1)
  92                 switch(ch) {
  93                 case 'G':
  94                         Gflag = 1;
  95                         break;
  96                 case 'P':
  97                         Pflag = 1;
  98                         break;
  99                 case 'g':
 100                         gflag = 1;
 101                         break;
 102                 case 'n':
 103                         nflag = 1;
 104                         break;
 105                 case 'p':
 106                         pflag = 1;
 107                         break;
 108                 case 'r':
 109                         rflag = 1;
 110                         break;
 111                 case 'u':
 112                         uflag = 1;
 113                         break;
 114                 case '?':
 115                 default:
 116                         usage();
 117                 }
 118         argc -= optind;
 119         argv += optind;
 120
 121         if (iswhoami && argc > 0)
 122                 usage();
 123
 124         switch(Gflag + Pflag + gflag + pflag + uflag) {
 125         case 1:
 126                 break;
 127         case 0:
 128                 if (!nflag && !rflag)
 129                         break;
 130                 /* FALLTHROUGH */
 131         default:
 132                 usage();
 133         }
 134
 135         pw = *argv ? who(*argv) : NULL;
 136
 137         if (gflag) {
 138                 id = pw ? pw->pw_gid : rflag ? getgid() : getegid();
 139                 if (nflag && (gr = getgrgid(id)))
 140                         (void)printf("%s\n", gr->gr_name);
 141                 else
 142                         (void)printf("%u\n", id);
 143                 exit(0);
 144         }
 145
 146         if (uflag) {
 147                 id = pw ? pw->pw_uid : rflag ? getuid() : geteuid();
 148                 if (nflag && (pw = getpwuid(id)))
 149                         (void)printf("%s\n", pw->pw_name);
 150                 else
 151                         (void)printf("%u\n", id);
 152                 exit(0);
 153         }
 154
 155         if (Gflag) {
 156                 group(pw, nflag);
 157                 exit(0);
 158         }
 159
 160         if (Pflag) {
 161                 pline(pw);
 162                 exit(0);
 163         }
 164
 165         if (pflag) {
 166                 pretty(pw);
 167                 exit(0);
 168         }
 169
 170         if (pw)
 171                 user(pw);
 172         else
 173                 current();
 174         exit(0);
 175 }
 176
 177 void
 178 pretty(struct passwd *pw)
 179 {
 180         struct group *gr;
 181         u_int eid, rid;
 182         char *login;
 183
 184         if (pw) {
 185                 (void)printf("uid\t%s\n", pw->pw_name);
 186                 (void)printf("groups\t");
 187                 group(pw, 1);
 188         } else {
 189                 if ((login = getlogin()) == NULL)
 190                         err(1, "getlogin");
 191
 192                 pw = getpwuid(rid = getuid());
 193                 if (pw == NULL || strcmp(login, pw->pw_name))
 194                         (void)printf("login\t%s\n", login);
 195                 if (pw)
 196                         (void)printf("uid\t%s\n", pw->pw_name);
 197                 else
 198                         (void)printf("uid\t%u\n", rid);
 199
 200                 if ((eid = geteuid()) != rid) {
 201                         if ((pw = getpwuid(eid)))
 202                                 (void)printf("euid\t%s\n", pw->pw_name);
 203                         else
 204                                 (void)printf("euid\t%u\n", eid);
 205                 }
 206                 if ((rid = getgid()) != (eid = getegid())) {
 207                         if ((gr = getgrgid(rid)))
 208                                 (void)printf("rgid\t%s\n", gr->gr_name);
 209                         else
 210                                 (void)printf("rgid\t%u\n", rid);
 211                 }
 212                 (void)printf("groups\t");
 213                 group(NULL, 1);
 214         }
 215 }
 216
 217 void
 218 current(void)
 219 {
 220         struct group *gr;
 221         struct passwd *pw;
 222         int cnt, id, eid, gid, egid, lastid, ngroups;
 223         gid_t groups[NGROUPS];
 224         const char *fmt;
 225
 226         id = getuid();
 227         (void)printf("uid=%u", id);
 228         if ((pw = getpwuid(id)))
 229                 (void)printf("(%s)", pw->pw_name);
 230         gid = getgid();
 231         (void)printf(" gid=%u", gid);
 232         if ((gr = getgrgid(gid)))
 233                 (void)printf("(%s)", gr->gr_name);
 234         if ((eid = geteuid()) != id) {
 235                 (void)printf(" euid=%u", eid);
 236                 if ((pw = getpwuid(eid)))
 237                         (void)printf("(%s)", pw->pw_name);
 238         }
 239         if ((egid = getegid()) != gid) {
 240                 (void)printf(" egid=%u", egid);
 241                 if ((gr = getgrgid(egid)))
 242                         (void)printf("(%s)", gr->gr_name);
 243         }
 244         if ((ngroups = getgroups(NGROUPS, groups))) {
 245                 for (fmt = " groups=%u", lastid = -1, cnt = 0; cnt < ngroups;
 246                     fmt = ", %u", lastid = id) {
 247                         id = groups[cnt++];
 248                         if (lastid == id)
 249                                 continue;
 250                         (void)printf(fmt, id);
 251                         if ((gr = getgrgid(id)))
 252                                 (void)printf("(%s)", gr->gr_name);
 253                 }
 254         }
 255         (void)printf("\n");
 256 }
 257
 258 void
 259 user(struct passwd *pw)
 260 {
 261         struct group *gr;
 262         const char *fmt;
 263         int cnt, gid, lastgid, ngroups, groups[NGROUPS + 1];
 264
 265         (void)printf("uid=%u(%s)", pw->pw_uid, pw->pw_name);
 266         gid = pw->pw_gid;
 267         (void)printf(" gid=%u", gid);
 268         if ((gr = getgrgid(gid)))
 269                 (void)printf("(%s)", gr->gr_name);
 270         ngroups = NGROUPS + 1;
 271         (void) getgrouplist(pw->pw_name, gid, groups, &ngroups);
 272         fmt = " groups=%u";
 273         for (lastgid = -1, cnt = 0; cnt < ngroups; ++cnt) {
 274                 if (lastgid == (gid = groups[cnt]))
 275                         continue;
 276                 (void)printf(fmt, gid);
 277                 fmt = ", %u";
 278                 if ((gr = getgrgid(gid)))
 279                         (void)printf("(%s)", gr->gr_name);
 280                 lastgid = gid;
 281         }
 282         (void)printf("\n");
 283 }
 284
 285 void
 286 group(struct passwd *pw, int nflag)
 287 {
 288         struct group *gr;
 289         int cnt, id, lastid, ngroups;
 290         gid_t groups[NGROUPS + 1];
 291         const char *fmt;
 292
 293         if (pw) {
 294                 ngroups = NGROUPS + 1;
 295                 (void) getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups);
 296         } else {
 297                 groups[0] = getgid();
 298                 ngroups = getgroups(NGROUPS, groups + 1) + 1;
 299         }
 300         fmt = nflag ? "%s" : "%u";
 301         for (lastid = -1, cnt = 0; cnt < ngroups; ++cnt) {
 302                 if (lastid == (id = groups[cnt]))
 303                         continue;
 304                 if (nflag) {
 305                         if ((gr = getgrgid(id)))
 306                                 (void)printf(fmt, gr->gr_name);
 307                         else
 308                                 (void)printf(*fmt == ' ' ? " %u" : "%u",
 309                                     id);
 310                         fmt = " %s";
 311                 } else {
 312                         (void)printf(fmt, id);
 313                         fmt = " %u";
 314                 }
 315                 lastid = id;
 316         }
 317         (void)printf("\n");
 318 }
 319
 320 struct passwd *
 321 who(char *u)
 322 {
 323         struct passwd *pw;
 324         long id;
 325         char *ep;
 326
 327         /*
 328          * Translate user argument into a pw pointer.  First, try to
 329          * get it as specified.  If that fails, try it as a number.
 330          */
 331         if ((pw = getpwnam(u)))
 332                 return(pw);
 333         id = strtol(u, &ep, 10);
 334         if (*u && !*ep && (pw = getpwuid(id)))
 335                 return(pw);
 336         errx(1, "%s: no such user", u);
 337         /* NOTREACHED */
 338 }
 339
 340 void
 341 pline(struct passwd *pw)
 342 {
 343         u_int rid;
 344
 345         if (!pw) {
 346                 if ((pw = getpwuid(rid = getuid())) == NULL)
 347                         err(1, "getpwuid");
 348         }
 349
 350         (void)printf("%s:%s:%d:%d:%s:%ld:%ld:%s:%s:%s\n", pw->pw_name,
 351                         pw->pw_passwd, pw->pw_uid, pw->pw_gid, pw->pw_class,
 352                         (long)pw->pw_change, (long)pw->pw_expire, pw->pw_gecos,
 353                         pw->pw_dir, pw->pw_shell);
 354 }
 355
 356
 357 void
 358 usage(void)
 359 {
 360
 361         if (isgroups)
 362                 (void)fprintf(stderr, "usage: groups [user]\n");
 363         else if (iswhoami)
 364                 (void)fprintf(stderr, "usage: whoami\n");
 365         else
 366                 (void)fprintf(stderr, "%s\n%s\n%s\n%s\n%s\n%s\n",
 367                     "usage: id [user]",
 368                     "       id -G [-n] [user]",
 369                     "       id -P [user]",
 370                     "       id -g [-nr] [user]",
 371                     "       id -p [user]",
 372                     "       id -u [-nr] [user]");
 373         exit(1);
 374 }