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. 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  * @(#) Copyright (c) 1991, 1993 The Regents of the University of California.  All rights reserved.
  34  * @(#)id.c     8.2 (Berkeley) 2/16/94
  35  * $FreeBSD: src/usr.bin/id/id.c,v 1.12.2.3 2001/12/20 12:09:03 ru Exp $
  36  * $DragonFly: src/usr.bin/id/id.c,v 1.6 2004/12/31 20:58:17 cpressey Exp $
  37  */
  38
  39 #include <sys/param.h>
  40
  41 #include <err.h>
  42 #include <grp.h>
  43 #include <pwd.h>
  44 #include <stdio.h>
  45 #include <stdlib.h>
  46 #include <string.h>
  47 #include <unistd.h>
  48
  49 int             main(int, char *[]);
  50 static void     current(void);
  51 static void     pline(struct passwd *);
  52 static void     pretty(struct passwd *);
  53 static void     group(struct passwd *, int);
  54 static void     usage(void);
  55 static void     user(struct passwd *);
  56 static struct passwd *
  57                 who(char *);
  58
  59 int isgroups, iswhoami;
  60
  61 int
  62 main(int argc, char **argv)
  63 {
  64         struct group *gr;
  65         struct passwd *pw;
  66         int Gflag, Pflag, ch, gflag, id, nflag, pflag, rflag, uflag;
  67         const char *myname;
  68
  69         Gflag = Pflag = gflag = nflag = pflag = rflag = uflag = 0;
  70
  71         myname = strrchr(argv[0], '/');
  72         myname = (myname != NULL) ? myname + 1 : argv[0];
  73         if (strcmp(myname, "groups") == 0) {
  74                 isgroups = 1;
  75                 Gflag = nflag = 1;
  76         }
  77         else if (strcmp(myname, "whoami") == 0) {
  78                 iswhoami = 1;
  79                 uflag = nflag = 1;
  80         }
  81
  82         while ((ch = getopt(argc, argv,
  83             (isgroups || iswhoami) ? "" : "PGgnpru")) != -1)
  84                 switch(ch) {
  85                 case 'G':
  86                         Gflag = 1;
  87                         break;
  88                 case 'P':
  89                         Pflag = 1;
  90                         break;
  91                 case 'g':
  92                         gflag = 1;
  93                         break;
  94                 case 'n':
  95                         nflag = 1;
  96                         break;
  97                 case 'p':
  98                         pflag = 1;
  99                         break;
 100                 case 'r':
 101                         rflag = 1;
 102                         break;
 103                 case 'u':
 104                         uflag = 1;
 105                         break;
 106                 case '?':
 107                 default:
 108                         usage();
 109                 }
 110         argc -= optind;
 111         argv += optind;
 112
 113         if (iswhoami && argc > 0)
 114                 usage();
 115
 116         switch(Gflag + Pflag + gflag + pflag + uflag) {
 117         case 1:
 118                 break;
 119         case 0:
 120                 if (!nflag && !rflag)
 121                         break;
 122                 /* FALLTHROUGH */
 123         default:
 124                 usage();
 125         }
 126
 127         pw = *argv ? who(*argv) : NULL;
 128
 129         if (gflag) {
 130                 id = pw ? pw->pw_gid : rflag ? getgid() : getegid();
 131                 if (nflag && (gr = getgrgid(id)))
 132                         printf("%s\n", gr->gr_name);
 133                 else
 134                         printf("%u\n", id);
 135                 exit(0);
 136         }
 137
 138         if (uflag) {
 139                 id = pw ? pw->pw_uid : rflag ? getuid() : geteuid();
 140                 if (nflag && (pw = getpwuid(id)))
 141                         printf("%s\n", pw->pw_name);
 142                 else
 143                         printf("%u\n", id);
 144                 exit(0);
 145         }
 146
 147         if (Gflag) {
 148                 group(pw, nflag);
 149                 exit(0);
 150         }
 151
 152         if (Pflag) {
 153                 pline(pw);
 154                 exit(0);
 155         }
 156
 157         if (pflag) {
 158                 pretty(pw);
 159                 exit(0);
 160         }
 161
 162         if (pw)
 163                 user(pw);
 164         else
 165                 current();
 166         exit(0);
 167 }
 168
 169 static void
 170 pretty(struct passwd *pw)
 171 {
 172         struct group *gr;
 173         u_int eid, rid;
 174         char *login;
 175
 176         if (pw) {
 177                 printf("uid\t%s\n", pw->pw_name);
 178                 printf("groups\t");
 179                 group(pw, 1);
 180         } else {
 181                 if ((login = getlogin()) == NULL)
 182                         err(1, "getlogin");
 183
 184                 pw = getpwuid(rid = getuid());
 185                 if (pw == NULL || strcmp(login, pw->pw_name))
 186                         printf("login\t%s\n", login);
 187                 if (pw)
 188                         printf("uid\t%s\n", pw->pw_name);
 189                 else
 190                         printf("uid\t%u\n", rid);
 191
 192                 if ((eid = geteuid()) != rid) {
 193                         if ((pw = getpwuid(eid)))
 194                                 printf("euid\t%s\n", pw->pw_name);
 195                         else
 196                                 printf("euid\t%u\n", eid);
 197                 }
 198                 if ((rid = getgid()) != (eid = getegid())) {
 199                         if ((gr = getgrgid(rid)))
 200                                 printf("rgid\t%s\n", gr->gr_name);
 201                         else
 202                                 printf("rgid\t%u\n", rid);
 203                 }
 204                 printf("groups\t");
 205                 group(NULL, 1);
 206         }
 207 }
 208
 209 static void
 210 current(void)
 211 {
 212         struct group *gr;
 213         struct passwd *pw;
 214         int cnt, id, eid, lastid, ngroups;
 215         gid_t groups[NGROUPS];
 216         const char *fmt;
 217
 218         id = getuid();
 219         printf("uid=%u", id);
 220         if ((pw = getpwuid(id)))
 221                 printf("(%s)", pw->pw_name);
 222         if ((eid = geteuid()) != id) {
 223                 printf(" euid=%u", eid);
 224                 if ((pw = getpwuid(eid)))
 225                         printf("(%s)", pw->pw_name);
 226         }
 227         id = getgid();
 228         printf(" gid=%u", id);
 229         if ((gr = getgrgid(id)))
 230                 printf("(%s)", gr->gr_name);
 231         if ((eid = getegid()) != id) {
 232                 printf(" egid=%u", eid);
 233                 if ((gr = getgrgid(eid)))
 234                         printf("(%s)", gr->gr_name);
 235         }
 236         if ((ngroups = getgroups(NGROUPS, groups))) {
 237                 for (fmt = " groups=%u", lastid = -1, cnt = 0; cnt < ngroups;
 238                     fmt = ", %u", lastid = id) {
 239                         id = groups[cnt++];
 240                         if (lastid == id)
 241                                 continue;
 242                         printf(fmt, id);
 243                         if ((gr = getgrgid(id)))
 244                                 printf("(%s)", gr->gr_name);
 245                 }
 246         }
 247         printf("\n");
 248 }
 249
 250 static void
 251 user(struct passwd *pw)
 252 {
 253         struct group *gr;
 254         const char *fmt;
 255         int cnt, ngroups;
 256         gid_t gid, lastgid, groups[NGROUPS + 1];
 257
 258         printf("uid=%u(%s)", pw->pw_uid, pw->pw_name);
 259         gid = pw->pw_gid;
 260         printf(" gid=%u", gid);
 261         if ((gr = getgrgid(gid)))
 262                 printf("(%s)", gr->gr_name);
 263         ngroups = NGROUPS + 1;
 264         getgrouplist(pw->pw_name, gid, groups, &ngroups);
 265         fmt = " groups=%u";
 266         for (lastgid = -1, cnt = 0; cnt < ngroups; ++cnt) {
 267                 if (lastgid == (gid = groups[cnt]))
 268                         continue;
 269                 printf(fmt, gid);
 270                 fmt = ", %u";
 271                 if ((gr = getgrgid(gid)))
 272                         printf("(%s)", gr->gr_name);
 273                 lastgid = gid;
 274         }
 275         printf("\n");
 276 }
 277
 278 static void
 279 group(struct passwd *pw, int nflag)
 280 {
 281         struct group *gr;
 282         int cnt, id, lastid, ngroups;
 283         gid_t groups[NGROUPS + 1];
 284         const char *fmt;
 285
 286         if (pw) {
 287                 ngroups = NGROUPS + 1;
 288                 getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups);
 289         } else {
 290                 groups[0] = getgid();
 291                 ngroups = getgroups(NGROUPS, groups + 1) + 1;
 292         }
 293         fmt = nflag ? "%s" : "%u";
 294         for (lastid = -1, cnt = 0; cnt < ngroups; ++cnt) {
 295                 if (lastid == (id = groups[cnt]))
 296                         continue;
 297                 if (nflag) {
 298                         if ((gr = getgrgid(id)))
 299                                 printf(fmt, gr->gr_name);
 300                         else
 301                                 printf(*fmt == ' ' ? " %u" : "%u",
 302                                     id);
 303                         fmt = " %s";
 304                 } else {
 305                         printf(fmt, id);
 306                         fmt = " %u";
 307                 }
 308                 lastid = id;
 309         }
 310         printf("\n");
 311 }
 312
 313 static struct passwd *
 314 who(char *u)
 315 {
 316         struct passwd *pw;
 317         long id;
 318         char *ep;
 319
 320         /*
 321          * Translate user argument into a pw pointer.  First, try to
 322          * get it as specified.  If that fails, try it as a number.
 323          */
 324         if ((pw = getpwnam(u)))
 325                 return(pw);
 326         id = strtol(u, &ep, 10);
 327         if (*u && !*ep && (pw = getpwuid(id)))
 328                 return(pw);
 329         errx(1, "%s: no such user", u);
 330         /* NOTREACHED */
 331 }
 332
 333 static void
 334 pline(struct passwd *pw)
 335 {
 336         u_int rid;
 337
 338         if (!pw) {
 339                 if ((pw = getpwuid(rid = getuid())) == NULL)
 340                         err(1, "getpwuid");
 341         }
 342
 343         printf("%s:%s:%d:%d:%s:%ld:%ld:%s:%s:%s\n", pw->pw_name,
 344                         pw->pw_passwd, pw->pw_uid, pw->pw_gid, pw->pw_class,
 345                         (long)pw->pw_change, (long)pw->pw_expire, pw->pw_gecos,
 346                         pw->pw_dir, pw->pw_shell);
 347 }
 348
 349
 350 static void
 351 usage(void)
 352 {
 353
 354         if (isgroups)
 355                 fprintf(stderr, "usage: groups [user]\n");
 356         else if (iswhoami)
 357                 fprintf(stderr, "usage: whoami\n");
 358         else
 359                 fprintf(stderr, "%s\n%s\n%s\n%s\n%s\n%s\n",
 360                     "usage: id [user]",
 361                     "       id -G [-n] [user]",
 362                     "       id -P [user]",
 363                     "       id -g [-nr] [user]",
 364                     "       id -p [user]",
 365                     "       id -u [-nr] [user]");
 366         exit(1);
 367 }