usr/src/lib/libc/port/gen/getgrnam_r.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  * Copyright (c) 2016 by Delphix. All rights reserved.
  26  */
  27
  28 #include "lint.h"
  29 #include <mtlib.h>
  30 #include <sys/types.h>
  31 #include <grp.h>
  32 #include <memory.h>
  33 #include <deflt.h>
  34 #include <nsswitch.h>
  35 #include <nss_dbdefs.h>
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <string.h>
  39 #include <synch.h>
  40 #include <sys/param.h>
  41 #include <sys/mman.h>
  42 #include <errno.h>
  43
  44 extern int _getgroupsbymember(const char *, gid_t[], int, int);
  45 int str2group(const char *, int, void *, char *, int);
  46
  47 static DEFINE_NSS_DB_ROOT(db_root);
  48 static DEFINE_NSS_GETENT(context);
  49
  50 #define USE_NETID_STR   "NETID_AUTHORITATIVE=TRUE"
  51
  52 void
  53 _nss_initf_group(nss_db_params_t *p)
  54 {
  55         p->name = NSS_DBNAM_GROUP;
  56         p->default_config = NSS_DEFCONF_GROUP;
  57 }
  58
  59 #include <getxby_door.h>
  60 #include <sys/door.h>
  61
  62 struct group *
  63 _uncached_getgrnam_r(const char *name, struct group *result, char *buffer,
  64     int buflen);
  65
  66 struct group *
  67 _uncached_getgrgid_r(gid_t gid, struct group *result, char *buffer, int buflen);
  68
  69 /*
  70  * POSIX.1c Draft-6 version of the function getgrnam_r.
  71  * It was implemented by Solaris 2.3.
  72  */
  73 struct group *
  74 getgrnam_r(const char *name, struct group *result, char *buffer, int buflen)
  75 {
  76         nss_XbyY_args_t arg;
  77
  78         if (name == (const char *)NULL) {
  79                 errno = ERANGE;
  80                 return (NULL);
  81         }
  82         NSS_XbyY_INIT(&arg, result, buffer, buflen, str2group);
  83         arg.key.name = name;
  84         (void) nss_search(&db_root, _nss_initf_group,
  85             NSS_DBOP_GROUP_BYNAME, &arg);
  86         return ((struct group *)NSS_XbyY_FINI(&arg));
  87 }
  88
  89 /*
  90  * POSIX.1c Draft-6 version of the function getgrgid_r.
  91  * It was implemented by Solaris 2.3.
  92  */
  93 struct group *
  94 getgrgid_r(gid_t gid, struct group *result, char *buffer, int buflen)
  95 {
  96         nss_XbyY_args_t arg;
  97
  98         NSS_XbyY_INIT(&arg, result, buffer, buflen, str2group);
  99         arg.key.gid = gid;
 100         (void) nss_search(&db_root, _nss_initf_group,
 101             NSS_DBOP_GROUP_BYGID, &arg);
 102         return ((struct group *)NSS_XbyY_FINI(&arg));
 103 }
 104
 105 struct group *
 106 _uncached_getgrgid_r(gid_t gid, struct group *result, char *buffer,
 107     int buflen)
 108 {
 109         nss_XbyY_args_t arg;
 110
 111         NSS_XbyY_INIT(&arg, result, buffer, buflen, str2group);
 112         arg.key.gid = gid;
 113         (void) nss_search(&db_root, _nss_initf_group,
 114             NSS_DBOP_GROUP_BYGID, &arg);
 115         return ((struct group *)NSS_XbyY_FINI(&arg));
 116 }
 117
 118 /*
 119  * POSIX.1c standard version of the function getgrgid_r.
 120  * User gets it via static getgrgid_r from the header file.
 121  */
 122 int
 123 __posix_getgrgid_r(gid_t gid, struct group *grp, char *buffer,
 124     size_t bufsize, struct group **result)
 125 {
 126         int nerrno = 0;
 127         int oerrno = errno;
 128
 129         errno = 0;
 130         if ((*result = getgrgid_r(gid, grp, buffer, (uintptr_t)bufsize))
 131             == NULL) {
 132                         nerrno = errno;
 133         }
 134         errno = oerrno;
 135         return (nerrno);
 136 }
 137
 138 struct group *
 139 _uncached_getgrnam_r(const char *name, struct group *result, char *buffer,
 140         int buflen)
 141 {
 142         nss_XbyY_args_t arg;
 143
 144         NSS_XbyY_INIT(&arg, result, buffer, buflen, str2group);
 145         arg.key.name = name;
 146         (void) nss_search(&db_root, _nss_initf_group,
 147             NSS_DBOP_GROUP_BYNAME, &arg);
 148         return ((struct group *)NSS_XbyY_FINI(&arg));
 149 }
 150
 151 /*
 152  * POSIX.1c standard version of the function getgrnam_r.
 153  * User gets it via static getgrnam_r from the header file.
 154  */
 155 int
 156 __posix_getgrnam_r(const char *name, struct group *grp, char *buffer,
 157     size_t bufsize, struct group **result)
 158 {
 159         int nerrno = 0;
 160         int oerrno = errno;
 161
 162         if ((*result = getgrnam_r(name, grp, buffer, (uintptr_t)bufsize))
 163             == NULL) {
 164                         nerrno = errno;
 165         }
 166         errno = oerrno;
 167         return (nerrno);
 168 }
 169
 170 void
 171 setgrent(void)
 172 {
 173         nss_setent(&db_root, _nss_initf_group, &context);
 174 }
 175
 176 void
 177 endgrent(void)
 178 {
 179         nss_endent(&db_root, _nss_initf_group, &context);
 180         nss_delete(&db_root);
 181 }
 182
 183 struct group *
 184 getgrent_r(struct group *result, char *buffer, int buflen)
 185 {
 186         nss_XbyY_args_t arg;
 187         char            *nam;
 188
 189         NSS_XbyY_INIT(&arg, result, buffer, buflen, str2group);
 190         /* No key to fill in */
 191         (void) nss_getent(&db_root, _nss_initf_group, &context, &arg);
 192
 193         return ((struct group *)NSS_XbyY_FINI(&arg));
 194 }
 195
 196 struct group *
 197 fgetgrent_r(FILE *f, struct group *result, char *buffer, int buflen)
 198 {
 199         extern void     _nss_XbyY_fgets(FILE *, nss_XbyY_args_t *);
 200         nss_XbyY_args_t arg;
 201
 202         /* No key to fill in */
 203         NSS_XbyY_INIT(&arg, result, buffer, buflen, str2group);
 204         _nss_XbyY_fgets(f, &arg);
 205         return ((struct group *)NSS_XbyY_FINI(&arg));
 206 }
 207
 208 /*
 209  * _getgroupsbymember(uname, gid_array, maxgids, numgids):
 210  *      Private interface for initgroups().  It returns the group ids of
 211  *      groups of which the specified user is a member.
 212  *
 213  * Arguments:
 214  *   username   Username of the putative member
 215  *   gid_array  Space in which to return the gids.  The first [numgids]
 216  *              elements are assumed to already contain valid gids.
 217  *   maxgids    Maximum number of elements in gid_array.
 218  *   numgids    Number of elements (normally 0 or 1) that already contain
 219  *              valid gids.
 220  * Return value:
 221  *   number of valid gids in gid_array (may be zero)
 222  *      or
 223  *   -1 (and errno set appropriately) on errors (none currently defined)
 224  *
 225  * NSS2 Consistency enhancements:
 226  *   The "files normal" format between an application and nscd for the
 227  *   NSS_DBOP_GROUP_BYMEMBER nss_search operation is defined to be a
 228  *   processed array of numgids [up to maxgids] gid_t values.  gid_t
 229  *   values in the array are unique.
 230  */
 231
 232 extern nss_status_t process_cstr(const char *, int, struct nss_groupsbymem *);
 233
 234 int
 235 _getgroupsbymember(const char *username, gid_t gid_array[],
 236     int maxgids, int numgids)
 237 {
 238         struct nss_groupsbymem  arg;
 239         void    *defp;
 240
 241         arg.username    = username;
 242         arg.gid_array   = gid_array;
 243         arg.maxgids     = maxgids;
 244         arg.numgids     = numgids;
 245         /*
 246          * In backwards compatibility mode, use the old str2group &
 247          * process_cstr interfaces.  Ditto within nscd processing.
 248          */
 249         arg.str2ent     = str2group;
 250         arg.process_cstr = process_cstr;
 251
 252         /*
 253          * The old value being provided here was 0, ie do the quick
 254          * way.  Given that this was never actually used under NIS
 255          * and had the wrong (now corrected) meaning for NIS+ we need
 256          * to change the default to be 1 (TRUE) as we now need the
 257          * admin to decided to use netid, setting NETID_AUTHORITATIVE
 258          * in /etc/default/nss to TRUE gets us a value of 0 for
 259          * force_slow_way - don't you just love double negatives ;-)
 260          *
 261          * We need to do this to preserve the behaviour seen when the
 262          * admin makes no changes.
 263          */
 264         arg.force_slow_way = 1;
 265
 266         if ((defp = defopen_r(__NSW_DEFAULT_FILE)) != NULL) {
 267                 if (defread_r(USE_NETID_STR, defp) != NULL)
 268                         arg.force_slow_way = 0;
 269                 defclose_r(defp);
 270         }
 271
 272         (void) nss_search(&db_root, _nss_initf_group,
 273             NSS_DBOP_GROUP_BYMEMBER, &arg);
 274
 275         return (arg.numgids);
 276 }
 277
 278
 279 static char *
 280 gettok(char **nextpp, char sep)
 281 {
 282         char    *p = *nextpp;
 283         char    *q = p;
 284         char    c;
 285
 286         if (p == 0)
 287                 return (0);
 288
 289         while ((c = *q) != '\0' && c != sep)
 290                 q++;
 291
 292         if (c == '\0')
 293                 *nextpp = 0;
 294         else {
 295                 *q++ = '\0';
 296                 *nextpp = q;
 297         }
 298         return (p);
 299 }
 300
 301 /*
 302  * Return values: 0 = success, 1 = parse error, 2 = erange ...
 303  * The structure pointer passed in is a structure in the caller's space
 304  * wherein the field pointers would be set to areas in the buffer if
 305  * need be. instring and buffer should be separate areas.
 306  */
 307 int
 308 str2group(const char *instr, int lenstr, void *ent, char *buffer, int buflen)
 309 {
 310         struct group            *group  = (struct group *)ent;
 311         char                    *p, *next;
 312         char                    **memlist, **limit;
 313         ulong_t                 tmp;
 314
 315         if (lenstr + 1 > buflen)
 316                 return (NSS_STR_PARSE_ERANGE);
 317
 318         /*
 319          * We copy the input string into the output buffer and
 320          * operate on it in place.
 321          */
 322         if (instr != buffer) {
 323                 /* Overlapping buffer copies are OK */
 324                 (void) memmove(buffer, instr, lenstr);
 325                 buffer[lenstr] = '\0';
 326         }
 327
 328         /* quick exit do not entry fill if not needed */
 329         if (ent == NULL)
 330                 return (NSS_STR_PARSE_SUCCESS);
 331
 332         next = buffer;
 333
 334         /*
 335          * Parsers for passwd and group have always been pretty rigid;
 336          * we wouldn't want to buck a Unix tradition
 337          */
 338
 339         group->gr_name = p = gettok(&next, ':');
 340         if (*p == '\0') {
 341                 /* Empty group-name;  not allowed */
 342                 return (NSS_STR_PARSE_PARSE);
 343         }
 344
 345         /* Always return at least an empty gr_mem list */
 346         memlist = (char **)ROUND_UP(buffer + lenstr + 1, sizeof (char *));
 347         limit   = (char **)ROUND_DOWN(buffer + buflen, sizeof (char *));
 348         *memlist = 0;
 349         group->gr_mem = memlist;
 350
 351         group->gr_passwd = p = gettok(&next, ':');
 352         if (p == 0)
 353                 return (NSS_STR_PARSE_PARSE);
 354
 355         p = next;                                       /* gid */
 356         if (p == 0 || *p == '\0')
 357                 return (NSS_STR_PARSE_PARSE);
 358
 359         errno = 0;
 360         tmp = strtoul(p, &next, 10);
 361         if (next == p || errno != 0) {
 362                 /* gid field should be nonempty */
 363                 /* also check errno from strtoul */
 364                 return (NSS_STR_PARSE_PARSE);
 365         }
 366         if (tmp >= UINT32_MAX)
 367                 group->gr_gid = GID_NOBODY;
 368         else
 369                 group->gr_gid = (gid_t)tmp;
 370
 371         if (*next++ != ':')
 372                 return (NSS_STR_PARSE_PARSE);
 373
 374         /* === Could check and complain if there are any extra colons */
 375         while (memlist < limit) {
 376                 p = gettok(&next, ',');
 377                 if (p == 0 || *p == '\0') {
 378                         *memlist = 0;
 379                         /* Successfully parsed and stored */
 380                         return (NSS_STR_PARSE_SUCCESS);
 381                 }
 382                 *memlist++ = p;
 383         }
 384         /* Out of space */
 385         return (NSS_STR_PARSE_ERANGE);
 386 }
 387
 388 nss_status_t
 389 process_cstr(const char *instr, int instr_len, struct nss_groupsbymem *gbm)
 390 {
 391         /*
 392          * It's possible to do a much less inefficient version of this by
 393          * selectively duplicating code from str2group().  For now,
 394          * however, we'll take the easy way out and implement this on
 395          * top of str2group().
 396          */
 397
 398         const char              *username = gbm->username;
 399         nss_XbyY_buf_t          *buf;
 400         struct group            *grp;
 401         char                    **memp;
 402         char                    *mem;
 403         int     parsestat;
 404
 405         buf = _nss_XbyY_buf_alloc(sizeof (struct group), NSS_BUFLEN_GROUP);
 406         if (buf == 0)
 407                 return (NSS_UNAVAIL);
 408
 409         grp = (struct group *)buf->result;
 410
 411         parsestat = (*gbm->str2ent)(instr, instr_len,
 412             grp, buf->buffer, buf->buflen);
 413
 414         if (parsestat != NSS_STR_PARSE_SUCCESS) {
 415                 _nss_XbyY_buf_free(buf);
 416                 return (NSS_NOTFOUND);  /* === ? */
 417         }
 418
 419         if (grp->gr_mem) {
 420                 for (memp = grp->gr_mem; (memp) && ((mem = *memp) != 0);
 421                     memp++) {
 422                         if (strcmp(mem, username) == 0) {
 423                                 gid_t   gid     = grp->gr_gid;
 424                                 gid_t   *gidp   = gbm->gid_array;
 425                                 int     numgids = gbm->numgids;
 426                                 int     i;
 427
 428                                 _nss_XbyY_buf_free(buf);
 429
 430                                 for (i = 0; i < numgids && *gidp != gid; i++,
 431                                     gidp++) {
 432                                         ;
 433                                 }
 434                                 if (i >= numgids) {
 435                                         if (i >= gbm->maxgids) {
 436                                         /* Filled the array;  stop searching */
 437                                                 return (NSS_SUCCESS);
 438                                         }
 439                                         *gidp = gid;
 440                                         gbm->numgids = numgids + 1;
 441                                 }
 442                                 return (NSS_NOTFOUND);  /* Explained in   */
 443                                                         /* <nss_dbdefs.h> */
 444                         }
 445                 }
 446         }
 447         _nss_XbyY_buf_free(buf);
 448         return (NSS_NOTFOUND);
 449 }