usr.sbin/pw/pw_group.c

   1 /*-
   2  * Copyright (C) 1996
   3  *      David L. Nugent.  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  *
  14  * THIS SOFTWARE IS PROVIDED BY DAVID L. NUGENT AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL DAVID L. NUGENT OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  *
  26  * $FreeBSD: src/usr.sbin/pw/pw_group.c,v 1.16 2008/02/23 01:25:22 scf Exp $
  27  */
  28
  29 #include <ctype.h>
  30 #include <err.h>
  31 #include <termios.h>
  32 #include <stdbool.h>
  33 #include <unistd.h>
  34
  35 #include "pw.h"
  36 #include "bitmap.h"
  37
  38
  39 static struct passwd *lookup_pwent(const char *user);
  40 static void     delete_members(char ***members, int *grmembers, int *i,
  41     struct carg *arg, struct group *grp);
  42 static int      print_group(struct group * grp, int pretty);
  43 static gid_t    gr_gidpolicy(struct userconf * cnf, struct cargs * args);
  44
  45 static
  46 int
  47 alldigits(const char *str)
  48 {
  49         while (*str) {
  50                 if (*str < '0' || *str > '9')
  51                         return(0);
  52                 ++str;
  53         }
  54         return(1);
  55 }
  56
  57 int
  58 pw_group(struct userconf * cnf, int mode, struct cargs * args)
  59 {
  60         int             rc;
  61         struct carg    *a_name = getarg(args, 'n');
  62         struct carg    *a_gid = getarg(args, 'g');
  63         struct carg    *arg;
  64         struct group   *grp = NULL;
  65         int             grmembers = 0;
  66         char           **members = NULL;
  67
  68         static struct group fakegroup =
  69         {
  70                 "nogroup",
  71                 "*",
  72                 -1,
  73                 NULL
  74         };
  75
  76         if (mode == M_LOCK || mode == M_UNLOCK)
  77                 errx(EX_USAGE, "'lock' command is not available for groups");
  78
  79         /*
  80          * With M_NEXT, we only need to return the
  81          * next gid to stdout
  82          */
  83         if (mode == M_NEXT) {
  84                 gid_t next = gr_gidpolicy(cnf, args);
  85                 if (getarg(args, 'q'))
  86                         return next;
  87                 printf("%ld\n", (long)next);
  88                 return EXIT_SUCCESS;
  89         }
  90
  91         if (mode == M_PRINT && getarg(args, 'a')) {
  92                 int             pretty = getarg(args, 'P') != NULL;
  93
  94                 SETGRENT();
  95                 while ((grp = GETGRENT()) != NULL)
  96                         print_group(grp, pretty);
  97                 ENDGRENT();
  98                 return EXIT_SUCCESS;
  99         }
 100         if (a_gid == NULL) {
 101                 if (a_name == NULL)
 102                         errx(EX_DATAERR, "group name or id required");
 103
 104                 if (mode != M_ADD && grp == NULL && alldigits(a_name->val)) {
 105                         (a_gid = a_name)->ch = 'g';
 106                         a_name = NULL;
 107                 }
 108         }
 109         grp = (a_name != NULL) ? GETGRNAM(a_name->val) : GETGRGID((gid_t) atoi(a_gid->val));
 110
 111         if (mode == M_UPDATE || mode == M_DELETE || mode == M_PRINT) {
 112                 if (a_name == NULL && grp == NULL)      /* Try harder */
 113                         grp = GETGRGID(atoi(a_gid->val));
 114
 115                 if (grp == NULL) {
 116                         if (mode == M_PRINT && getarg(args, 'F')) {
 117                                 char    *fmems[1];
 118                                 fmems[0] = NULL;
 119                                 fakegroup.gr_name = a_name ? a_name->val : "nogroup";
 120                                 fakegroup.gr_gid = a_gid ? (gid_t) atol(a_gid->val) : -1;
 121                                 fakegroup.gr_mem = fmems;
 122                                 return print_group(&fakegroup, getarg(args, 'P') != NULL);
 123                         }
 124                         errx(EX_DATAERR, "unknown group `%s'", a_name ? a_name->val : a_gid->val);
 125                 }
 126                 if (a_name == NULL)     /* Needed later */
 127                         a_name = addarg(args, 'n', grp->gr_name);
 128
 129                 /*
 130                  * Handle deletions now
 131                  */
 132                 if (mode == M_DELETE) {
 133                         gid_t           gid = grp->gr_gid;
 134
 135                         rc = delgrent(grp);
 136                         if (rc == -1)
 137                                 err(EX_IOERR, "group '%s' not available (NIS?)", grp->gr_name);
 138                         else if (rc != 0) {
 139                                 warn("group update");
 140                                 return EX_IOERR;
 141                         }
 142                         pw_log(cnf, mode, W_GROUP, "%s(%ld) removed", a_name->val, (long) gid);
 143                         return EXIT_SUCCESS;
 144                 } else if (mode == M_PRINT)
 145                         return print_group(grp, getarg(args, 'P') != NULL);
 146
 147                 if (a_gid)
 148                         grp->gr_gid = (gid_t) atoi(a_gid->val);
 149
 150                 if ((arg = getarg(args, 'l')) != NULL)
 151                         grp->gr_name = pw_checkname((u_char *)arg->val, 0);
 152         } else {
 153                 if (a_name == NULL)     /* Required */
 154                         errx(EX_DATAERR, "group name required");
 155                 else if (grp != NULL)   /* Exists */
 156                         errx(EX_DATAERR, "group name `%s' already exists", a_name->val);
 157
 158                 extendarray(&members, &grmembers, 200);
 159                 members[0] = NULL;
 160                 grp = &fakegroup;
 161                 grp->gr_name = pw_checkname((u_char *)a_name->val, 0);
 162                 grp->gr_passwd = "*";
 163                 grp->gr_gid = gr_gidpolicy(cnf, args);
 164                 grp->gr_mem = members;
 165         }
 166
 167         /*
 168          * This allows us to set a group password Group passwords is an
 169          * antique idea, rarely used and insecure (no secure database) Should
 170          * be discouraged, but it is apparently still supported by some
 171          * software.
 172          */
 173
 174         if ((arg = getarg(args, 'h')) != NULL ||
 175             (arg = getarg(args, 'H')) != NULL) {
 176                 if (strcmp(arg->val, "-") == 0)
 177                         grp->gr_passwd = "*";   /* No access */
 178                 else {
 179                         int             fd = atoi(arg->val);
 180                         int             precrypt = (arg->ch == 'H');
 181                         int             b;
 182                         int             istty = isatty(fd);
 183                         struct termios  t;
 184                         char           *p, line[256];
 185
 186                         if (istty) {
 187                                 if (tcgetattr(fd, &t) == -1)
 188                                         istty = 0;
 189                                 else {
 190                                         struct termios  n = t;
 191
 192                                         /* Disable echo */
 193                                         n.c_lflag &= ~(ECHO);
 194                                         tcsetattr(fd, TCSANOW, &n);
 195                                         printf("%sassword for group %s:", (mode == M_UPDATE) ? "New p" : "P", grp->gr_name);
 196                                         fflush(stdout);
 197                                 }
 198                         }
 199                         b = read(fd, line, sizeof(line) - 1);
 200                         if (istty) {    /* Restore state */
 201                                 tcsetattr(fd, TCSANOW, &t);
 202                                 fputc('\n', stdout);
 203                                 fflush(stdout);
 204                         }
 205                         if (b < 0) {
 206                                 warn("-h file descriptor");
 207                                 return EX_OSERR;
 208                         }
 209                         line[b] = '\0';
 210                         if ((p = strpbrk(line, " \t\r\n")) != NULL)
 211                                 *p = '\0';
 212                         if (!*line)
 213                                 errx(EX_DATAERR, "empty password read on file descriptor %d", fd);
 214                         if (precrypt) {
 215                                 if (strchr(line, ':') != NULL)
 216                                         return EX_DATAERR;
 217                                 grp->gr_passwd = line;
 218                         } else
 219                                 grp->gr_passwd = pw_pwcrypt(line);
 220                 }
 221         }
 222
 223         if (((arg = getarg(args, 'M')) != NULL ||
 224             (arg = getarg(args, 'd')) != NULL ||
 225             (arg = getarg(args, 'm')) != NULL) && arg->val) {
 226                 int     i = 0;
 227                 char   *p;
 228                 struct passwd   *pwd;
 229
 230                 /* Make sure this is not stay NULL with -M "" */
 231                 extendarray(&members, &grmembers, 200);
 232                 if (arg->ch == 'd')
 233                         delete_members(&members, &grmembers, &i, arg, grp);
 234                 else if (arg->ch == 'm') {
 235                         int     k = 0;
 236
 237                         while (grp->gr_mem[k] != NULL) {
 238                                 if (extendarray(&members, &grmembers, i + 2) != -1)
 239                                         members[i++] = grp->gr_mem[k];
 240                                 k++;
 241                         }
 242                 }
 243
 244                 if (arg->ch != 'd')
 245                         for (p = strtok(arg->val, ", \t"); p != NULL; p = strtok(NULL, ", \t")) {
 246                                 int     j;
 247
 248                                 /*
 249                                  * Check for duplicates
 250                                  */
 251                                 pwd = lookup_pwent(p);
 252                                 for (j = 0; j < i && strcmp(members[j], pwd->pw_name) != 0; j++)
 253                                         ;
 254                                 if (j == i && extendarray(&members, &grmembers, i + 2) != -1)
 255                                         members[i++] = newstr(pwd->pw_name);
 256                         }
 257                 while (i < grmembers)
 258                         members[i++] = NULL;
 259                 grp->gr_mem = members;
 260         }
 261
 262         if (getarg(args, 'N') != NULL)
 263                 return print_group(grp, getarg(args, 'P') != NULL);
 264
 265         if (mode == M_ADD && (rc = addgrent(grp)) != 0) {
 266                 if (rc == -1)
 267                         warnx("group '%s' already exists", grp->gr_name);
 268                 else
 269                         warn("group update");
 270                 return EX_IOERR;
 271         } else if (mode == M_UPDATE && (rc = chggrent(a_name->val, grp)) != 0) {
 272                 if (rc == -1)
 273                         warnx("group '%s' not available (NIS?)", grp->gr_name);
 274                 else
 275                         warn("group update");
 276                 return EX_IOERR;
 277         }
 278         /* grp may have been invalidated */
 279         if ((grp = GETGRNAM(a_name->val)) == NULL)
 280                 errx(EX_SOFTWARE, "group disappeared during update");
 281
 282         pw_log(cnf, mode, W_GROUP, "%s(%ld)", grp->gr_name, (long) grp->gr_gid);
 283
 284         if (members)
 285                 free(members);
 286
 287         return EXIT_SUCCESS;
 288 }
 289
 290
 291 /*
 292  * Lookup a passwd entry using a name or UID.
 293  */
 294 static struct passwd *
 295 lookup_pwent(const char *user)
 296 {
 297         struct passwd *pwd;
 298
 299         if ((pwd = GETPWNAM(user)) == NULL &&
 300             (!isdigit((unsigned char)*user) ||
 301             (pwd = getpwuid((uid_t) atoi(user))) == NULL))
 302                 errx(EX_NOUSER, "user `%s' does not exist", user);
 303
 304         return (pwd);
 305 }
 306
 307
 308 /*
 309  * Delete requested members from a group.
 310  */
 311 static void
 312 delete_members(char ***members, int *grmembers, int *i, struct carg *arg,
 313     struct group *grp)
 314 {
 315         bool matchFound;
 316         char *user;
 317         char *valueCopy;
 318         char *valuePtr;
 319         int k;
 320         struct passwd *pwd;
 321
 322         k = 0;
 323         while (grp->gr_mem[k] != NULL) {
 324                 matchFound = false;
 325                 if ((valueCopy = strdup(arg->val)) == NULL)
 326                         errx(EX_UNAVAILABLE, "out of memory");
 327                 valuePtr = valueCopy;
 328                 while ((user = strsep(&valuePtr, ", \t")) != NULL) {
 329                         pwd = lookup_pwent(user);
 330                         if (strcmp(grp->gr_mem[k], pwd->pw_name) == 0) {
 331                                 matchFound = true;
 332                                 break;
 333                         }
 334                 }
 335                 free(valueCopy);
 336
 337                 if (!matchFound &&
 338                     extendarray(members, grmembers, *i + 2) != -1)
 339                         (*members)[(*i)++] = grp->gr_mem[k];
 340
 341                 k++;
 342         }
 343
 344         return;
 345 }
 346
 347
 348 static          gid_t
 349 gr_gidpolicy(struct userconf * cnf, struct cargs * args)
 350 {
 351         struct group   *grp;
 352         gid_t           gid = (gid_t) - 1;
 353         struct carg    *a_gid = getarg(args, 'g');
 354
 355         /*
 356          * Check the given gid, if any
 357          */
 358         if (a_gid != NULL) {
 359                 gid = (gid_t) atol(a_gid->val);
 360
 361                 if ((grp = GETGRGID(gid)) != NULL && getarg(args, 'o') == NULL)
 362                         errx(EX_DATAERR, "gid `%ld' has already been allocated", (long) grp->gr_gid);
 363         } else {
 364                 struct bitmap   bm;
 365
 366                 /*
 367                  * We need to allocate the next available gid under one of
 368                  * two policies a) Grab the first unused gid b) Grab the
 369                  * highest possible unused gid
 370                  */
 371                 if (cnf->min_gid >= cnf->max_gid) {     /* Sanity claus^H^H^H^Hheck */
 372                         cnf->min_gid = 1000;
 373                         cnf->max_gid = 32000;
 374                 }
 375                 bm = bm_alloc(cnf->max_gid - cnf->min_gid + 1);
 376
 377                 /*
 378                  * Now, let's fill the bitmap from the password file
 379                  */
 380                 SETGRENT();
 381                 while ((grp = GETGRENT()) != NULL)
 382                         if ((gid_t)grp->gr_gid >= (gid_t)cnf->min_gid &&
 383                             (gid_t)grp->gr_gid <= (gid_t)cnf->max_gid)
 384                                 bm_setbit(&bm, grp->gr_gid - cnf->min_gid);
 385                 ENDGRENT();
 386
 387                 /*
 388                  * Then apply the policy, with fallback to reuse if necessary
 389                  */
 390                 if (cnf->reuse_gids)
 391                         gid = (gid_t) (bm_firstunset(&bm) + cnf->min_gid);
 392                 else {
 393                         gid = (gid_t) (bm_lastset(&bm) + 1);
 394                         if (!bm_isset(&bm, gid))
 395                                 gid += cnf->min_gid;
 396                         else
 397                                 gid = (gid_t) (bm_firstunset(&bm) + cnf->min_gid);
 398                 }
 399
 400                 /*
 401                  * Another sanity check
 402                  */
 403                 if (gid < cnf->min_gid || gid > cnf->max_gid)
 404                         errx(EX_SOFTWARE, "unable to allocate a new gid - range fully used");
 405                 bm_dealloc(&bm);
 406         }
 407         return gid;
 408 }
 409
 410
 411 static int
 412 print_group(struct group * grp, int pretty)
 413 {
 414         if (!pretty) {
 415                 int             buflen = 0;
 416                 char           *buf = NULL;
 417
 418                 fmtgrent(&buf, &buflen, grp);
 419                 fputs(buf, stdout);
 420                 free(buf);
 421         } else {
 422                 int             i;
 423
 424                 printf("Group Name: %-15s   #%lu\n"
 425                        "   Members: ",
 426                        grp->gr_name, (long) grp->gr_gid);
 427                 for (i = 0; grp->gr_mem[i]; i++)
 428                         printf("%s%s", i ? "," : "", grp->gr_mem[i]);
 429                 fputs("\n\n", stdout);
 430         }
 431         return EXIT_SUCCESS;
 432 }