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  * Copyright (c) 2012, Intel Corporation.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  *
  36  * lustre/obdclass/idmap.c
  37  *
  38  * Lustre user identity mapping.
  39  *
  40  * Author: Fan Yong <fanyong@clusterfs.com>
  41  */
  42
  43 #define DEBUG_SUBSYSTEM S_SEC
  44
  45 #include <libcfs/lucache.h>
  46
  47 #include <lustre_idmap.h>
  48 #include <md_object.h>
  49 #include <obd_support.h>
  50
  51 #define lustre_get_group_info(group_info) do {             \
  52         atomic_inc(&(group_info)->usage);              \
  53 } while (0)
  54
  55 #define lustre_put_group_info(group_info) do {             \
  56         if (atomic_dec_and_test(&(group_info)->usage)) \
  57                 groups_free(group_info);                   \
  58 } while (0)
  59
  60 /*
  61  * groups_search() is copied from linux kernel!
  62  * A simple bsearch.
  63  */
  64 static int lustre_groups_search(struct group_info *group_info,
  65                                 gid_t grp)
  66 {
  67         int left, right;
  68
  69         if (!group_info)
  70                 return 0;
  71
  72         left = 0;
  73         right = group_info->ngroups;
  74         while (left < right) {
  75                 int mid = (left + right) / 2;
  76                 int cmp = grp -
  77                         from_kgid(&init_user_ns, CFS_GROUP_AT(group_info, mid));
  78
  79                 if (cmp > 0)
  80                         left = mid + 1;
  81                 else if (cmp < 0)
  82                         right = mid;
  83                 else
  84                         return 1;
  85         }
  86         return 0;
  87 }
  88
  89 void lustre_groups_from_list(struct group_info *ginfo, gid_t *glist)
  90 {
  91         int i;
  92         int count = ginfo->ngroups;
  93
  94         /* fill group_info from gid array */
  95         for (i = 0; i < ginfo->nblocks && count > 0; i++) {
  96                 int cp_count = min(CFS_NGROUPS_PER_BLOCK, count);
  97                 int off = i * CFS_NGROUPS_PER_BLOCK;
  98                 int len = cp_count * sizeof(*glist);
  99
 100                 memcpy(ginfo->blocks[i], glist + off, len);
 101                 count -= cp_count;
 102         }
 103 }
 104 EXPORT_SYMBOL(lustre_groups_from_list);
 105
 106 /* groups_sort() is copied from linux kernel! */
 107 /* a simple shell-metzner sort */
 108 void lustre_groups_sort(struct group_info *group_info)
 109 {
 110         int base, max, stride;
 111         int gidsetsize = group_info->ngroups;
 112
 113         for (stride = 1; stride < gidsetsize; stride = 3 * stride + 1)
 114                 ; /* nothing */
 115         stride /= 3;
 116
 117         while (stride) {
 118                 max = gidsetsize - stride;
 119                 for (base = 0; base < max; base++) {
 120                         int left = base;
 121                         int right = left + stride;
 122                         gid_t tmp = from_kgid(&init_user_ns,
 123                                               CFS_GROUP_AT(group_info, right));
 124
 125                         while (left >= 0 &&
 126                                tmp < from_kgid(&init_user_ns,
 127                                                CFS_GROUP_AT(group_info, left))) {
 128                                 CFS_GROUP_AT(group_info, right) =
 129                                         CFS_GROUP_AT(group_info, left);
 130                                 right = left;
 131                                 left -= stride;
 132                         }
 133                         CFS_GROUP_AT(group_info, right) =
 134                                                 make_kgid(&init_user_ns, tmp);
 135                 }
 136                 stride /= 3;
 137         }
 138 }
 139 EXPORT_SYMBOL(lustre_groups_sort);
 140
 141 int lustre_in_group_p(struct lu_ucred *mu, gid_t grp)
 142 {
 143         int rc = 1;
 144
 145         if (grp != mu->uc_fsgid) {
 146                 struct group_info *group_info = NULL;
 147
 148                 if (mu->uc_ginfo || !mu->uc_identity ||
 149                     mu->uc_valid == UCRED_OLD)
 150                         if (grp == mu->uc_suppgids[0] ||
 151                             grp == mu->uc_suppgids[1])
 152                                 return 1;
 153
 154                 if (mu->uc_ginfo)
 155                         group_info = mu->uc_ginfo;
 156                 else if (mu->uc_identity)
 157                         group_info = mu->uc_identity->mi_ginfo;
 158
 159                 if (!group_info)
 160                         return 0;
 161
 162                 lustre_get_group_info(group_info);
 163                 rc = lustre_groups_search(group_info, grp);
 164                 lustre_put_group_info(group_info);
 165         }
 166         return rc;
 167 }
 168 EXPORT_SYMBOL(lustre_in_group_p);
 169
 170 struct lustre_idmap_entry {
 171         struct list_head       lie_rmt_uid_hash; /* hashed as lie_rmt_uid; */
 172         struct list_head       lie_lcl_uid_hash; /* hashed as lie_lcl_uid; */
 173         struct list_head       lie_rmt_gid_hash; /* hashed as lie_rmt_gid; */
 174         struct list_head       lie_lcl_gid_hash; /* hashed as lie_lcl_gid; */
 175         uid_t            lie_rmt_uid;      /* remote uid */
 176         uid_t            lie_lcl_uid;      /* local uid */
 177         gid_t            lie_rmt_gid;      /* remote gid */
 178         gid_t            lie_lcl_gid;      /* local gid */
 179 };
 180
 181 static inline __u32 lustre_idmap_hashfunc(__u32 id)
 182 {
 183         return id & (CFS_IDMAP_HASHSIZE - 1);
 184 }
 185
 186 static
 187 struct lustre_idmap_entry *idmap_entry_alloc(uid_t rmt_uid, uid_t lcl_uid,
 188                                              gid_t rmt_gid, gid_t lcl_gid)
 189 {
 190         struct lustre_idmap_entry *e;
 191
 192         OBD_ALLOC_PTR(e);
 193         if (e == NULL)
 194                 return NULL;
 195
 196         INIT_LIST_HEAD(&e->lie_rmt_uid_hash);
 197         INIT_LIST_HEAD(&e->lie_lcl_uid_hash);
 198         INIT_LIST_HEAD(&e->lie_rmt_gid_hash);
 199         INIT_LIST_HEAD(&e->lie_lcl_gid_hash);
 200         e->lie_rmt_uid = rmt_uid;
 201         e->lie_lcl_uid = lcl_uid;
 202         e->lie_rmt_gid = rmt_gid;
 203         e->lie_lcl_gid = lcl_gid;
 204
 205         return e;
 206 }
 207
 208 static void idmap_entry_free(struct lustre_idmap_entry *e)
 209 {
 210         list_del(&e->lie_rmt_uid_hash);
 211         list_del(&e->lie_lcl_uid_hash);
 212         list_del(&e->lie_rmt_gid_hash);
 213         list_del(&e->lie_lcl_gid_hash);
 214         OBD_FREE_PTR(e);
 215 }
 216
 217 /*
 218  * return value
 219  * NULL: not found entry
 220  * ERR_PTR(-EACCES): found 1(remote):N(local) mapped entry
 221  * others: found normal entry
 222  */
 223 static
 224 struct lustre_idmap_entry *idmap_search_entry(struct lustre_idmap_table *t,
 225                                               uid_t rmt_uid, uid_t lcl_uid,
 226                                               gid_t rmt_gid, gid_t lcl_gid)
 227 {
 228         struct list_head *head;
 229         struct lustre_idmap_entry *e;
 230
 231         head = &t->lit_idmaps[RMT_UIDMAP_IDX][lustre_idmap_hashfunc(rmt_uid)];
 232         list_for_each_entry(e, head, lie_rmt_uid_hash)
 233                 if (e->lie_rmt_uid == rmt_uid) {
 234                         if (e->lie_lcl_uid == lcl_uid) {
 235                                 if (e->lie_rmt_gid == rmt_gid &&
 236                                     e->lie_lcl_gid == lcl_gid)
 237                                         /* must be quaternion match */
 238                                         return e;
 239                         } else {
 240                                 /* 1:N uid mapping */
 241                                 CERROR("rmt uid %u already be mapped to %u"
 242                                        " (new %u)\n", e->lie_rmt_uid,
 243                                        e->lie_lcl_uid, lcl_uid);
 244                                 return ERR_PTR(-EACCES);
 245                         }
 246                 }
 247
 248         head = &t->lit_idmaps[RMT_GIDMAP_IDX][lustre_idmap_hashfunc(rmt_gid)];
 249         list_for_each_entry(e, head, lie_rmt_gid_hash)
 250                 if (e->lie_rmt_gid == rmt_gid) {
 251                         if (e->lie_lcl_gid == lcl_gid) {
 252                                 if (unlikely(e->lie_rmt_uid == rmt_uid &&
 253                                     e->lie_lcl_uid == lcl_uid))
 254                                         /* after uid mapping search above,
 255                                          * we should never come here */
 256                                         LBUG();
 257                         } else {
 258                                 /* 1:N gid mapping */
 259                                 CERROR("rmt gid %u already be mapped to %u"
 260                                        " (new %u)\n", e->lie_rmt_gid,
 261                                        e->lie_lcl_gid, lcl_gid);
 262                                 return ERR_PTR(-EACCES);
 263                         }
 264                 }
 265
 266         return NULL;
 267 }
 268
 269 static __u32 idmap_lookup_uid(struct list_head *hash, int reverse,
 270                               __u32 uid)
 271 {
 272         struct list_head *head = &hash[lustre_idmap_hashfunc(uid)];
 273         struct lustre_idmap_entry *e;
 274
 275         if (!reverse) {
 276                 list_for_each_entry(e, head, lie_rmt_uid_hash)
 277                         if (e->lie_rmt_uid == uid)
 278                                 return e->lie_lcl_uid;
 279         } else {
 280                 list_for_each_entry(e, head, lie_lcl_uid_hash)
 281                         if (e->lie_lcl_uid == uid)
 282                                 return e->lie_rmt_uid;
 283         }
 284
 285         return CFS_IDMAP_NOTFOUND;
 286 }
 287
 288 static __u32 idmap_lookup_gid(struct list_head *hash, int reverse, __u32 gid)
 289 {
 290         struct list_head *head = &hash[lustre_idmap_hashfunc(gid)];
 291         struct lustre_idmap_entry *e;
 292
 293         if (!reverse) {
 294                 list_for_each_entry(e, head, lie_rmt_gid_hash)
 295                         if (e->lie_rmt_gid == gid)
 296                                 return e->lie_lcl_gid;
 297         } else {
 298                 list_for_each_entry(e, head, lie_lcl_gid_hash)
 299                         if (e->lie_lcl_gid == gid)
 300                                 return e->lie_rmt_gid;
 301         }
 302
 303         return CFS_IDMAP_NOTFOUND;
 304 }
 305
 306 int lustre_idmap_add(struct lustre_idmap_table *t,
 307                      uid_t ruid, uid_t luid,
 308                      gid_t rgid, gid_t lgid)
 309 {
 310         struct lustre_idmap_entry *e0, *e1;
 311
 312         LASSERT(t);
 313
 314         spin_lock(&t->lit_lock);
 315         e0 = idmap_search_entry(t, ruid, luid, rgid, lgid);
 316         spin_unlock(&t->lit_lock);
 317         if (!e0) {
 318                 e0 = idmap_entry_alloc(ruid, luid, rgid, lgid);
 319                 if (!e0)
 320                         return -ENOMEM;
 321
 322                 spin_lock(&t->lit_lock);
 323                 e1 = idmap_search_entry(t, ruid, luid, rgid, lgid);
 324                 if (e1 == NULL) {
 325                         list_add_tail(&e0->lie_rmt_uid_hash,
 326                                       &t->lit_idmaps[RMT_UIDMAP_IDX]
 327                                       [lustre_idmap_hashfunc(ruid)]);
 328                         list_add_tail(&e0->lie_lcl_uid_hash,
 329                                       &t->lit_idmaps[LCL_UIDMAP_IDX]
 330                                       [lustre_idmap_hashfunc(luid)]);
 331                         list_add_tail(&e0->lie_rmt_gid_hash,
 332                                       &t->lit_idmaps[RMT_GIDMAP_IDX]
 333                                       [lustre_idmap_hashfunc(rgid)]);
 334                         list_add_tail(&e0->lie_lcl_gid_hash,
 335                                       &t->lit_idmaps[LCL_GIDMAP_IDX]
 336                                       [lustre_idmap_hashfunc(lgid)]);
 337                 }
 338                 spin_unlock(&t->lit_lock);
 339                 if (e1 != NULL) {
 340                         idmap_entry_free(e0);
 341                         if (IS_ERR(e1))
 342                                 return PTR_ERR(e1);
 343                 }
 344         } else if (IS_ERR(e0)) {
 345                 return PTR_ERR(e0);
 346         }
 347
 348         return 0;
 349 }
 350 EXPORT_SYMBOL(lustre_idmap_add);
 351
 352 int lustre_idmap_del(struct lustre_idmap_table *t,
 353                     uid_t ruid, uid_t luid,
 354                     gid_t rgid, gid_t lgid)
 355 {
 356         struct lustre_idmap_entry *e;
 357         int rc = 0;
 358
 359         LASSERT(t);
 360
 361         spin_lock(&t->lit_lock);
 362         e = idmap_search_entry(t, ruid, luid, rgid, lgid);
 363         if (IS_ERR(e))
 364                 rc = PTR_ERR(e);
 365         else if (e)
 366                 idmap_entry_free(e);
 367         spin_unlock(&t->lit_lock);
 368
 369         return rc;
 370 }
 371 EXPORT_SYMBOL(lustre_idmap_del);
 372
 373 int lustre_idmap_lookup_uid(struct lu_ucred *mu,
 374                             struct lustre_idmap_table *t,
 375                             int reverse, uid_t uid)
 376 {
 377         struct list_head *hash;
 378
 379         if (mu && (mu->uc_valid == UCRED_OLD || mu->uc_valid == UCRED_NEW)) {
 380                 if (!reverse) {
 381                         if (uid == mu->uc_o_uid)
 382                                 return mu->uc_uid;
 383                         else if (uid == mu->uc_o_fsuid)
 384                                 return mu->uc_fsuid;
 385                 } else {
 386                         if (uid == mu->uc_uid)
 387                                 return mu->uc_o_uid;
 388                         else if (uid == mu->uc_fsuid)
 389                                 return mu->uc_o_fsuid;
 390                 }
 391         }
 392
 393         if (t == NULL)
 394                 return CFS_IDMAP_NOTFOUND;
 395
 396         hash = t->lit_idmaps[reverse ? LCL_UIDMAP_IDX : RMT_UIDMAP_IDX];
 397
 398         spin_lock(&t->lit_lock);
 399         uid = idmap_lookup_uid(hash, reverse, uid);
 400         spin_unlock(&t->lit_lock);
 401
 402         return uid;
 403 }
 404 EXPORT_SYMBOL(lustre_idmap_lookup_uid);
 405
 406 int lustre_idmap_lookup_gid(struct lu_ucred *mu, struct lustre_idmap_table *t,
 407                             int reverse, gid_t gid)
 408 {
 409         struct list_head *hash;
 410
 411         if (mu && (mu->uc_valid == UCRED_OLD || mu->uc_valid == UCRED_NEW)) {
 412                 if (!reverse) {
 413                         if (gid == mu->uc_o_gid)
 414                                 return mu->uc_gid;
 415                         else if (gid == mu->uc_o_fsgid)
 416                                 return mu->uc_fsgid;
 417                 } else {
 418                         if (gid == mu->uc_gid)
 419                                 return mu->uc_o_gid;
 420                         else if (gid == mu->uc_fsgid)
 421                                 return mu->uc_o_fsgid;
 422                 }
 423         }
 424
 425         if (t == NULL)
 426                 return CFS_IDMAP_NOTFOUND;
 427
 428         hash = t->lit_idmaps[reverse ? LCL_GIDMAP_IDX : RMT_GIDMAP_IDX];
 429
 430         spin_lock(&t->lit_lock);
 431         gid = idmap_lookup_gid(hash, reverse, gid);
 432         spin_unlock(&t->lit_lock);
 433
 434         return gid;
 435 }
 436 EXPORT_SYMBOL(lustre_idmap_lookup_gid);
 437
 438 struct lustre_idmap_table *lustre_idmap_init(void)
 439 {
 440         struct lustre_idmap_table *t;
 441         int i, j;
 442
 443         OBD_ALLOC_PTR(t);
 444         if(unlikely(t == NULL))
 445                 return (ERR_PTR(-ENOMEM));
 446
 447         spin_lock_init(&t->lit_lock);
 448         for (i = 0; i < ARRAY_SIZE(t->lit_idmaps); i++)
 449                 for (j = 0; j < ARRAY_SIZE(t->lit_idmaps[i]); j++)
 450                         INIT_LIST_HEAD(&t->lit_idmaps[i][j]);
 451
 452         return t;
 453 }
 454 EXPORT_SYMBOL(lustre_idmap_init);
 455
 456 void lustre_idmap_fini(struct lustre_idmap_table *t)
 457 {
 458         struct list_head *list;
 459         struct lustre_idmap_entry *e;
 460         int i;
 461         LASSERT(t);
 462
 463         list = t->lit_idmaps[RMT_UIDMAP_IDX];
 464         spin_lock(&t->lit_lock);
 465         for (i = 0; i < CFS_IDMAP_HASHSIZE; i++)
 466                 while (!list_empty(&list[i])) {
 467                         e = list_entry(list[i].next,
 468                                        struct lustre_idmap_entry,
 469                                        lie_rmt_uid_hash);
 470                         idmap_entry_free(e);
 471                 }
 472         spin_unlock(&t->lit_lock);
 473
 474         OBD_FREE_PTR(t);
 475 }
 476 EXPORT_SYMBOL(lustre_idmap_fini);