lustre/obdclass/idmap.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  */
  30 /*
  31  * This file is part of Lustre, http://www.lustre.org/
  32  * Lustre is a trademark of Sun Microsystems, Inc.
  33  *
  34  * lustre/obdclass/idmap.c
  35  *
  36  * Lustre user identity mapping.
  37  *
  38  * Author: Fan Yong <fanyong@clusterfs.com>
  39  */
  40
  41 #define DEBUG_SUBSYSTEM S_SEC
  42
  43 #include <lustre_idmap.h>
  44 #include <obd_support.h>
  45
  46 #define lustre_get_group_info(group_info) do {             \
  47         cfs_atomic_inc(&(group_info)->usage);              \
  48 } while (0)
  49
  50 #define lustre_put_group_info(group_info) do {             \
  51         if (cfs_atomic_dec_and_test(&(group_info)->usage)) \
  52                 cfs_groups_free(group_info);               \
  53 } while (0)
  54
  55 /*
  56  * groups_search() is copied from linux kernel!
  57  * A simple bsearch.
  58  */
  59 static int lustre_groups_search(cfs_group_info_t *group_info,
  60                                 gid_t grp)
  61 {
  62         int left, right;
  63
  64         if (!group_info)
  65                 return 0;
  66
  67         left = 0;
  68         right = group_info->ngroups;
  69         while (left < right) {
  70                 int mid = (left + right) / 2;
  71                 int cmp = grp - CFS_GROUP_AT(group_info, mid);
  72
  73                 if (cmp > 0)
  74                         left = mid + 1;
  75                 else if (cmp < 0)
  76                         right = mid;
  77                 else
  78                         return 1;
  79         }
  80         return 0;
  81 }
  82
  83 void lustre_groups_from_list(cfs_group_info_t *ginfo, gid_t *glist)
  84 {
  85         int i;
  86         int count = ginfo->ngroups;
  87
  88         /* fill group_info from gid array */
  89         for (i = 0; i < ginfo->nblocks && count > 0; i++) {
  90                 int cp_count = min(CFS_NGROUPS_PER_BLOCK, count);
  91                 int off = i * CFS_NGROUPS_PER_BLOCK;
  92                 int len = cp_count * sizeof(*glist);
  93
  94                 memcpy(ginfo->blocks[i], glist + off, len);
  95                 count -= cp_count;
  96         }
  97 }
  98 EXPORT_SYMBOL(lustre_groups_from_list);
  99
 100 /* groups_sort() is copied from linux kernel! */
 101 /* a simple shell-metzner sort */
 102 void lustre_groups_sort(cfs_group_info_t *group_info)
 103 {
 104         int base, max, stride;
 105         int gidsetsize = group_info->ngroups;
 106
 107         for (stride = 1; stride < gidsetsize; stride = 3 * stride + 1)
 108                 ; /* nothing */
 109         stride /= 3;
 110
 111         while (stride) {
 112                 max = gidsetsize - stride;
 113                 for (base = 0; base < max; base++) {
 114                         int left = base;
 115                         int right = left + stride;
 116                         gid_t tmp = CFS_GROUP_AT(group_info, right);
 117
 118                         while (left >= 0 &&
 119                                CFS_GROUP_AT(group_info, left) > tmp) {
 120                                 CFS_GROUP_AT(group_info, right) =
 121                                     CFS_GROUP_AT(group_info, left);
 122                                 right = left;
 123                                 left -= stride;
 124                         }
 125                         CFS_GROUP_AT(group_info, right) = tmp;
 126                 }
 127                 stride /= 3;
 128         }
 129 }
 130 EXPORT_SYMBOL(lustre_groups_sort);
 131
 132 int lustre_in_group_p(struct md_ucred *mu, gid_t grp)
 133 {
 134         int rc = 1;
 135
 136         if (grp != mu->mu_fsgid) {
 137                 cfs_group_info_t *group_info = NULL;
 138
 139                 if (mu->mu_ginfo || !mu->mu_identity ||
 140                     mu->mu_valid == UCRED_OLD)
 141                         if (grp == mu->mu_suppgids[0] ||
 142                             grp == mu->mu_suppgids[1])
 143                                 return 1;
 144
 145                 if (mu->mu_ginfo)
 146                         group_info = mu->mu_ginfo;
 147                 else if (mu->mu_identity)
 148                         group_info = mu->mu_identity->mi_ginfo;
 149
 150                 if (!group_info)
 151                         return 0;
 152
 153                 lustre_get_group_info(group_info);
 154                 rc = lustre_groups_search(group_info, grp);
 155                 lustre_put_group_info(group_info);
 156         }
 157         return rc;
 158 }
 159 EXPORT_SYMBOL(lustre_in_group_p);
 160
 161 struct lustre_idmap_entry {
 162         cfs_list_t       lie_rmt_uid_hash; /* hashed as lie_rmt_uid; */
 163         cfs_list_t       lie_lcl_uid_hash; /* hashed as lie_lcl_uid; */
 164         cfs_list_t       lie_rmt_gid_hash; /* hashed as lie_rmt_gid; */
 165         cfs_list_t       lie_lcl_gid_hash; /* hashed as lie_lcl_gid; */
 166         uid_t            lie_rmt_uid;      /* remote uid */
 167         uid_t            lie_lcl_uid;      /* local uid */
 168         gid_t            lie_rmt_gid;      /* remote gid */
 169         gid_t            lie_lcl_gid;      /* local gid */
 170 };
 171
 172 static inline __u32 lustre_idmap_hashfunc(__u32 id)
 173 {
 174         return id & (CFS_IDMAP_HASHSIZE - 1);
 175 }
 176
 177 static
 178 struct lustre_idmap_entry *idmap_entry_alloc(uid_t rmt_uid, uid_t lcl_uid,
 179                                              gid_t rmt_gid, gid_t lcl_gid)
 180 {
 181         struct lustre_idmap_entry *e;
 182
 183         OBD_ALLOC_PTR(e);
 184         if (e == NULL)
 185                 return NULL;
 186
 187         CFS_INIT_LIST_HEAD(&e->lie_rmt_uid_hash);
 188         CFS_INIT_LIST_HEAD(&e->lie_lcl_uid_hash);
 189         CFS_INIT_LIST_HEAD(&e->lie_rmt_gid_hash);
 190         CFS_INIT_LIST_HEAD(&e->lie_lcl_gid_hash);
 191         e->lie_rmt_uid = rmt_uid;
 192         e->lie_lcl_uid = lcl_uid;
 193         e->lie_rmt_gid = rmt_gid;
 194         e->lie_lcl_gid = lcl_gid;
 195
 196         return e;
 197 }
 198
 199 static void idmap_entry_free(struct lustre_idmap_entry *e)
 200 {
 201         if (!cfs_list_empty(&e->lie_rmt_uid_hash))
 202                 cfs_list_del(&e->lie_rmt_uid_hash);
 203         if (!cfs_list_empty(&e->lie_lcl_uid_hash))
 204                 cfs_list_del(&e->lie_lcl_uid_hash);
 205         if (!cfs_list_empty(&e->lie_rmt_gid_hash))
 206                 cfs_list_del(&e->lie_rmt_gid_hash);
 207         if (!cfs_list_empty(&e->lie_lcl_gid_hash))
 208                 cfs_list_del(&e->lie_lcl_gid_hash);
 209         OBD_FREE_PTR(e);
 210 }
 211
 212 /*
 213  * return value
 214  * NULL: not found entry
 215  * ERR_PTR(-EACCES): found 1(remote):N(local) mapped entry
 216  * others: found normal entry
 217  */
 218 static
 219 struct lustre_idmap_entry *idmap_search_entry(struct lustre_idmap_table *t,
 220                                               uid_t rmt_uid, uid_t lcl_uid,
 221                                               gid_t rmt_gid, gid_t lcl_gid)
 222 {
 223         cfs_list_t *head;
 224         struct lustre_idmap_entry *e;
 225
 226         head = &t->lit_idmaps[RMT_UIDMAP_IDX][lustre_idmap_hashfunc(rmt_uid)];
 227         cfs_list_for_each_entry(e, head, lie_rmt_uid_hash)
 228                 if (e->lie_rmt_uid == rmt_uid) {
 229                         if (e->lie_lcl_uid == lcl_uid) {
 230                                 if (e->lie_rmt_gid == rmt_gid &&
 231                                     e->lie_lcl_gid == lcl_gid)
 232                                         /* must be quaternion match */
 233                                         return e;
 234                         } else {
 235                                 /* 1:N uid mapping */
 236                                 CERROR("rmt uid %u already be mapped to %u"
 237                                        " (new %u)\n", e->lie_rmt_uid,
 238                                        e->lie_lcl_uid, lcl_uid);
 239                                 return ERR_PTR(-EACCES);
 240                         }
 241                 }
 242
 243         head = &t->lit_idmaps[RMT_GIDMAP_IDX][lustre_idmap_hashfunc(rmt_gid)];
 244         cfs_list_for_each_entry(e, head, lie_rmt_gid_hash)
 245                 if (e->lie_rmt_gid == rmt_gid) {
 246                         if (e->lie_lcl_gid == lcl_gid) {
 247                                 if (unlikely(e->lie_rmt_uid == rmt_uid &&
 248                                     e->lie_lcl_uid == lcl_uid))
 249                                         /* after uid mapping search above,
 250                                          * we should never come here */
 251                                         LBUG();
 252                         } else {
 253                                 /* 1:N gid mapping */
 254                                 CERROR("rmt gid %u already be mapped to %u"
 255                                        " (new %u)\n", e->lie_rmt_gid,
 256                                        e->lie_lcl_gid, lcl_gid);
 257                                 return ERR_PTR(-EACCES);
 258                         }
 259                 }
 260
 261         return NULL;
 262 }
 263
 264 static __u32 idmap_lookup_uid(cfs_list_t *hash, int reverse,
 265                               __u32 uid)
 266 {
 267         cfs_list_t *head = &hash[lustre_idmap_hashfunc(uid)];
 268         struct lustre_idmap_entry *e;
 269
 270         if (!reverse) {
 271                 cfs_list_for_each_entry(e, head, lie_rmt_uid_hash)
 272                         if (e->lie_rmt_uid == uid)
 273                                 return e->lie_lcl_uid;
 274         } else {
 275                 cfs_list_for_each_entry(e, head, lie_lcl_uid_hash)
 276                         if (e->lie_lcl_uid == uid)
 277                                 return e->lie_rmt_uid;
 278         }
 279
 280         return CFS_IDMAP_NOTFOUND;
 281 }
 282
 283 static __u32 idmap_lookup_gid(cfs_list_t *hash, int reverse, __u32 gid)
 284 {
 285         cfs_list_t *head = &hash[lustre_idmap_hashfunc(gid)];
 286         struct lustre_idmap_entry *e;
 287
 288         if (!reverse) {
 289                 cfs_list_for_each_entry(e, head, lie_rmt_gid_hash)
 290                         if (e->lie_rmt_gid == gid)
 291                                 return e->lie_lcl_gid;
 292         } else {
 293                 cfs_list_for_each_entry(e, head, lie_lcl_gid_hash)
 294                         if (e->lie_lcl_gid == gid)
 295                                 return e->lie_rmt_gid;
 296         }
 297
 298         return CFS_IDMAP_NOTFOUND;
 299 }
 300
 301 int lustre_idmap_add(struct lustre_idmap_table *t,
 302                      uid_t ruid, uid_t luid,
 303                      gid_t rgid, gid_t lgid)
 304 {
 305         struct lustre_idmap_entry *e0, *e1;
 306
 307         LASSERT(t);
 308
 309         spin_lock(&t->lit_lock);
 310         e0 = idmap_search_entry(t, ruid, luid, rgid, lgid);
 311         spin_unlock(&t->lit_lock);
 312         if (!e0) {
 313                 e0 = idmap_entry_alloc(ruid, luid, rgid, lgid);
 314                 if (!e0)
 315                         return -ENOMEM;
 316
 317                 spin_lock(&t->lit_lock);
 318                 e1 = idmap_search_entry(t, ruid, luid, rgid, lgid);
 319                 if (e1 == NULL) {
 320                         cfs_list_add_tail(&e0->lie_rmt_uid_hash,
 321                                           &t->lit_idmaps[RMT_UIDMAP_IDX]
 322                                           [lustre_idmap_hashfunc(ruid)]);
 323                         cfs_list_add_tail(&e0->lie_lcl_uid_hash,
 324                                           &t->lit_idmaps[LCL_UIDMAP_IDX]
 325                                           [lustre_idmap_hashfunc(luid)]);
 326                         cfs_list_add_tail(&e0->lie_rmt_gid_hash,
 327                                           &t->lit_idmaps[RMT_GIDMAP_IDX]
 328                                           [lustre_idmap_hashfunc(rgid)]);
 329                         cfs_list_add_tail(&e0->lie_lcl_gid_hash,
 330                                           &t->lit_idmaps[LCL_GIDMAP_IDX]
 331                                           [lustre_idmap_hashfunc(lgid)]);
 332                 }
 333                 spin_unlock(&t->lit_lock);
 334                 if (e1 != NULL) {
 335                         idmap_entry_free(e0);
 336                         if (IS_ERR(e1))
 337                                 return PTR_ERR(e1);
 338                 }
 339         } else if (IS_ERR(e0)) {
 340                 return PTR_ERR(e0);
 341         }
 342
 343         return 0;
 344 }
 345 EXPORT_SYMBOL(lustre_idmap_add);
 346
 347 int lustre_idmap_del(struct lustre_idmap_table *t,
 348                     uid_t ruid, uid_t luid,
 349                     gid_t rgid, gid_t lgid)
 350 {
 351         struct lustre_idmap_entry *e;
 352         int rc = 0;
 353
 354         LASSERT(t);
 355
 356         spin_lock(&t->lit_lock);
 357         e = idmap_search_entry(t, ruid, luid, rgid, lgid);
 358         if (IS_ERR(e))
 359                 rc = PTR_ERR(e);
 360         else if (e)
 361                 idmap_entry_free(e);
 362         spin_unlock(&t->lit_lock);
 363
 364         return rc;
 365 }
 366 EXPORT_SYMBOL(lustre_idmap_del);
 367
 368 int lustre_idmap_lookup_uid(struct md_ucred *mu,
 369                             struct lustre_idmap_table *t,
 370                             int reverse, uid_t uid)
 371 {
 372         cfs_list_t *hash;
 373
 374         if (mu && (mu->mu_valid == UCRED_OLD || mu->mu_valid == UCRED_NEW)) {
 375                 if (!reverse) {
 376                         if (uid == mu->mu_o_uid)
 377                                 return mu->mu_uid;
 378                         else if (uid == mu->mu_o_fsuid)
 379                                 return mu->mu_fsuid;
 380                 } else {
 381                         if (uid == mu->mu_uid)
 382                                 return mu->mu_o_uid;
 383                         else if (uid == mu->mu_fsuid)
 384                                 return mu->mu_o_fsuid;
 385                 }
 386         }
 387
 388         if (t == NULL)
 389                 return CFS_IDMAP_NOTFOUND;
 390
 391         hash = t->lit_idmaps[reverse ? LCL_UIDMAP_IDX : RMT_UIDMAP_IDX];
 392
 393         spin_lock(&t->lit_lock);
 394         uid = idmap_lookup_uid(hash, reverse, uid);
 395         spin_unlock(&t->lit_lock);
 396
 397         return uid;
 398 }
 399 EXPORT_SYMBOL(lustre_idmap_lookup_uid);
 400
 401 int lustre_idmap_lookup_gid(struct md_ucred *mu, struct lustre_idmap_table *t,
 402                             int reverse, gid_t gid)
 403 {
 404         cfs_list_t *hash;
 405
 406         if (mu && (mu->mu_valid == UCRED_OLD || mu->mu_valid == UCRED_NEW)) {
 407                 if (!reverse) {
 408                         if (gid == mu->mu_o_gid)
 409                                 return mu->mu_gid;
 410                         else if (gid == mu->mu_o_fsgid)
 411                                 return mu->mu_fsgid;
 412                 } else {
 413                         if (gid == mu->mu_gid)
 414                                 return mu->mu_o_gid;
 415                         else if (gid == mu->mu_fsgid)
 416                                 return mu->mu_o_fsgid;
 417                 }
 418         }
 419
 420         if (t == NULL)
 421                 return CFS_IDMAP_NOTFOUND;
 422
 423         hash = t->lit_idmaps[reverse ? LCL_GIDMAP_IDX : RMT_GIDMAP_IDX];
 424
 425         spin_lock(&t->lit_lock);
 426         gid = idmap_lookup_gid(hash, reverse, gid);
 427         spin_unlock(&t->lit_lock);
 428
 429         return gid;
 430 }
 431 EXPORT_SYMBOL(lustre_idmap_lookup_gid);
 432
 433 struct lustre_idmap_table *lustre_idmap_init(void)
 434 {
 435         struct lustre_idmap_table *t;
 436         int i, j;
 437
 438         OBD_ALLOC_PTR(t);
 439         if(unlikely(t == NULL))
 440                 return (ERR_PTR(-ENOMEM));
 441
 442         spin_lock_init(&t->lit_lock);
 443         for (i = 0; i < ARRAY_SIZE(t->lit_idmaps); i++)
 444                 for (j = 0; j < ARRAY_SIZE(t->lit_idmaps[i]); j++)
 445                         CFS_INIT_LIST_HEAD(&t->lit_idmaps[i][j]);
 446
 447         return t;
 448 }
 449 EXPORT_SYMBOL(lustre_idmap_init);
 450
 451 void lustre_idmap_fini(struct lustre_idmap_table *t)
 452 {
 453         cfs_list_t *list;
 454         struct lustre_idmap_entry *e;
 455         int i;
 456         LASSERT(t);
 457
 458         list = t->lit_idmaps[RMT_UIDMAP_IDX];
 459         spin_lock(&t->lit_lock);
 460         for (i = 0; i < CFS_IDMAP_HASHSIZE; i++)
 461                 while (!cfs_list_empty(&list[i])) {
 462                         e = cfs_list_entry(list[i].next,
 463                                            struct lustre_idmap_entry,
 464                                            lie_rmt_uid_hash);
 465                         idmap_entry_free(e);
 466                 }
 467         spin_unlock(&t->lit_lock);
 468
 469         OBD_FREE_PTR(t);
 470 }
 471 EXPORT_SYMBOL(lustre_idmap_fini);