lustre/mds/mds_lib.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  *  Copyright (c) 2003 Cluster File Systems, Inc.
   5  *
   6  *   This file is part of Lustre, http://www.lustre.org.
   7  *
   8  *   Lustre is free software; you can redistribute it and/or
   9  *   modify it under the terms of version 2 of the GNU General Public
  10  *   License as published by the Free Software Foundation.
  11  *
  12  *   Lustre is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU General Public License
  18  *   along with Lustre; if not, write to the Free Software
  19  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  */
  21
  22 #define DEBUG_SUBSYSTEM S_MDS
  23
  24 #include <linux/config.h>
  25 #include <linux/module.h>
  26 #include <linux/kernel.h>
  27 #include <linux/mm.h>
  28 #include <linux/string.h>
  29 #include <linux/stat.h>
  30 #include <linux/errno.h>
  31 #include <linux/version.h>
  32 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
  33 # include <linux/locks.h>   // for wait_on_buffer
  34 #else
  35 # include <linux/buffer_head.h>   // for wait_on_buffer
  36 #endif
  37 #include <linux/unistd.h>
  38
  39 #include <asm/system.h>
  40 #include <asm/uaccess.h>
  41
  42 #include <linux/fs.h>
  43 #include <linux/stat.h>
  44 #include <asm/uaccess.h>
  45 #include <linux/slab.h>
  46 #include <asm/segment.h>
  47
  48 #include <linux/obd_support.h>
  49 #include <linux/lustre_lib.h>
  50 #include <linux/lustre_ucache.h>
  51 #include "mds_internal.h"
  52
  53 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,4)
  54 struct group_info *groups_alloc(int ngroups)
  55 {
  56         struct group_info *ginfo;
  57
  58         LASSERT(ngroups <= NGROUPS_SMALL);
  59
  60         OBD_ALLOC(ginfo, sizeof(*ginfo) + 1 * sizeof(gid_t *));
  61         if (!ginfo)
  62                 return NULL;
  63         ginfo->ngroups = ngroups;
  64         ginfo->nblocks = 1;
  65         ginfo->blocks[0] = ginfo->small_block;
  66         atomic_set(&ginfo->usage, 1);
  67
  68         return ginfo;
  69 }
  70
  71 void groups_free(struct group_info *ginfo)
  72 {
  73         LASSERT(ginfo->ngroups <= NGROUPS_SMALL);
  74         LASSERT(ginfo->nblocks == 1);
  75         LASSERT(ginfo->blocks[0] == ginfo->small_block);
  76
  77         OBD_FREE(ginfo, sizeof(*ginfo) + 1 * sizeof(gid_t *));
  78 }
  79
  80 /* for 2.4 the group number is small, so simply search the
  81  * whole array.
  82  */
  83 int groups_search(struct group_info *ginfo, gid_t grp)
  84 {
  85         int i;
  86
  87         if (!ginfo)
  88                 return 0;
  89
  90         for (i = 0; i < ginfo->ngroups; i++)
  91                 if (GROUP_AT(ginfo, i) == grp)
  92                         return 1;
  93         return 0;
  94 }
  95
  96 #else /* >= 2.6.4 */
  97
  98 void groups_sort(struct group_info *ginfo)
  99 {
 100         int base, max, stride;
 101         int gidsetsize = ginfo->ngroups;
 102
 103         for (stride = 1; stride < gidsetsize; stride = 3 * stride + 1)
 104                 ; /* nothing */
 105         stride /= 3;
 106
 107         while (stride) {
 108                 max = gidsetsize - stride;
 109                 for (base = 0; base < max; base++) {
 110                         int left = base;
 111                         int right = left + stride;
 112                         gid_t tmp = GROUP_AT(ginfo, right);
 113
 114                         while (left >= 0 && GROUP_AT(ginfo, left) > tmp) {
 115                                 GROUP_AT(ginfo, right) =
 116                                     GROUP_AT(ginfo, left);
 117                                 right = left;
 118                                 left -= stride;
 119                         }
 120                         GROUP_AT(ginfo, right) = tmp;
 121                 }
 122                 stride /= 3;
 123         }
 124 }
 125
 126 int groups_search(struct group_info *ginfo, gid_t grp)
 127 {
 128         int left, right;
 129
 130         if (!ginfo)
 131                 return 0;
 132
 133         left = 0;
 134         right = ginfo->ngroups;
 135         while (left < right) {
 136                 int mid = (left + right) / 2;
 137                 int cmp = grp - GROUP_AT(ginfo, mid);
 138                 if (cmp > 0)
 139                         left = mid + 1;
 140                 else if (cmp < 0)
 141                         right = mid;
 142                 else
 143                         return 1;
 144         }
 145         return 0;
 146 }
 147 #endif
 148
 149 void groups_from_buffer(struct group_info *ginfo, __u32 *gids)
 150 {
 151         int i, ngroups = ginfo->ngroups;
 152
 153         for (i = 0; i < ginfo->nblocks; i++) {
 154                 int count = min(NGROUPS_PER_BLOCK, ngroups);
 155
 156                 memcpy(ginfo->blocks[i], gids, count * sizeof(__u32));
 157                 gids += NGROUPS_PER_BLOCK;
 158                 ngroups -= count;
 159         }
 160 }
 161
 162 void mds_pack_dentry2id(struct obd_device *obd,
 163                         struct lustre_id *id,
 164                         struct dentry *dentry,
 165                         int fid)
 166 {
 167         id_ino(id) = dentry->d_inum;
 168         id_gen(id) = dentry->d_generation;
 169
 170         if (fid) {
 171                 id_fid(id) = dentry->d_fid;
 172                 id_group(id) = dentry->d_mdsnum;
 173         }
 174 }
 175
 176 void mds_pack_dentry2body(struct obd_device *obd,
 177                           struct mds_body *b,
 178                           struct dentry *dentry,
 179                           int fid)
 180 {
 181         b->valid |= OBD_MD_FLID | OBD_MD_FLGENER |
 182                 OBD_MD_MDS;
 183
 184         if (fid)
 185                 b->valid |= OBD_MD_FID;
 186
 187         mds_pack_dentry2id(obd, &b->id1, dentry, fid);
 188 }
 189
 190 int mds_pack_inode2id(struct obd_device *obd,
 191                       struct lustre_id *id,
 192                       struct inode *inode,
 193                       int fid)
 194 {
 195         int rc = 0;
 196         ENTRY;
 197
 198         if (fid) {
 199                 /* we have to avoid deadlock. */
 200                 if (!down_trylock(&inode->i_sem)) {
 201                         rc = mds_read_inode_sid(obd, inode, id);
 202                         up(&inode->i_sem);
 203                 } else {
 204                         rc = mds_read_inode_sid(obd, inode, id);
 205                 }
 206         }
 207
 208         if (rc == 0) {
 209                 id_ino(id) = inode->i_ino;
 210                 id_gen(id) = inode->i_generation;
 211                 id_type(id) = (S_IFMT & inode->i_mode);
 212         }
 213         RETURN(rc);
 214 }
 215
 216 /* Note that we can copy all of the fields, just some will not be "valid" */
 217 void mds_pack_inode2body(struct obd_device *obd, struct mds_body *b,
 218                          struct inode *inode, int fid)
 219 {
 220         b->valid |= OBD_MD_FLID | OBD_MD_FLCTIME | OBD_MD_FLUID |
 221                 OBD_MD_FLGID | OBD_MD_FLFLAGS | OBD_MD_FLTYPE |
 222                 OBD_MD_FLMODE | OBD_MD_FLNLINK | OBD_MD_FLGENER |
 223                 OBD_MD_FLATIME | OBD_MD_FLMTIME; /* bug 2020 */
 224
 225         if (!S_ISREG(inode->i_mode)) {
 226                 b->valid |= OBD_MD_FLSIZE | OBD_MD_FLBLOCKS |
 227                         OBD_MD_FLATIME | OBD_MD_FLMTIME |
 228                         OBD_MD_FLRDEV;
 229         }
 230         b->atime = LTIME_S(inode->i_atime);
 231         b->mtime = LTIME_S(inode->i_mtime);
 232         b->ctime = LTIME_S(inode->i_ctime);
 233         b->mode = inode->i_mode;
 234         b->size = inode->i_size;
 235         b->blocks = inode->i_blocks;
 236         b->uid = inode->i_uid;
 237         b->gid = inode->i_gid;
 238         b->flags = inode->i_flags;
 239         b->rdev = inode->i_rdev;
 240
 241         /* Return the correct link count for orphan inodes */
 242         if (mds_inode_is_orphan(inode)) {
 243                 b->nlink = 0;
 244         } else if (S_ISDIR(inode->i_mode)) {
 245                 b->nlink = 1;
 246         } else {
 247                 b->nlink = inode->i_nlink;
 248         }
 249
 250         if (fid)
 251                 b->valid |= OBD_MD_FID;
 252
 253         mds_pack_inode2id(obd, &b->id1, inode, fid);
 254 }
 255
 256 /* unpacking */
 257 static int mds_setattr_unpack(struct ptlrpc_request *req, int offset,
 258                               struct mds_update_record *r)
 259 {
 260         struct iattr *attr = &r->ur_iattr;
 261         struct mds_rec_setattr *rec;
 262         ENTRY;
 263
 264         rec = lustre_swab_reqbuf(req, offset, sizeof(*rec),
 265                                  lustre_swab_mds_rec_setattr);
 266         if (rec == NULL)
 267                 RETURN (-EFAULT);
 268
 269         r->ur_id1 = &rec->sa_id;
 270         attr->ia_valid = rec->sa_valid;
 271         attr->ia_mode = rec->sa_mode;
 272         attr->ia_uid = rec->sa_uid;
 273         attr->ia_gid = rec->sa_gid;
 274         attr->ia_size = rec->sa_size;
 275         LTIME_S(attr->ia_atime) = rec->sa_atime;
 276         LTIME_S(attr->ia_mtime) = rec->sa_mtime;
 277         LTIME_S(attr->ia_ctime) = rec->sa_ctime;
 278         attr->ia_attr_flags = rec->sa_attr_flags;
 279
 280         LASSERT_REQSWAB (req, offset + 1);
 281         if (req->rq_reqmsg->bufcount > offset + 1) {
 282                 r->ur_eadata = lustre_msg_buf (req->rq_reqmsg,
 283                                                offset + 1, 0);
 284                 if (r->ur_eadata == NULL)
 285                         RETURN (-EFAULT);
 286                 r->ur_eadatalen = req->rq_reqmsg->buflens[offset + 1];
 287         }
 288
 289         if (req->rq_reqmsg->bufcount > offset + 2) {
 290                 r->ur_ea2data = lustre_msg_buf(req->rq_reqmsg, offset + 2, 0);
 291                 if (r->ur_ea2data == NULL)
 292                         RETURN (-EFAULT);
 293
 294                 r->ur_ea2datalen = req->rq_reqmsg->buflens[offset + 2];
 295         }
 296
 297         RETURN(0);
 298 }
 299
 300 static int mds_create_unpack(struct ptlrpc_request *req, int offset,
 301                              struct mds_update_record *r)
 302 {
 303         struct mds_rec_create *rec;
 304         ENTRY;
 305
 306         rec = lustre_swab_reqbuf (req, offset, sizeof (*rec),
 307                                   lustre_swab_mds_rec_create);
 308         if (rec == NULL)
 309                 RETURN (-EFAULT);
 310
 311         r->ur_id1 = &rec->cr_id;
 312         r->ur_id2 = &rec->cr_replayid;
 313         r->ur_mode = rec->cr_mode;
 314         r->ur_rdev = rec->cr_rdev;
 315         r->ur_time = rec->cr_time;
 316         r->ur_flags = rec->cr_flags;
 317
 318         LASSERT_REQSWAB (req, offset + 1);
 319         r->ur_name = lustre_msg_string (req->rq_reqmsg, offset + 1, 0);
 320         if (r->ur_name == NULL)
 321                 RETURN (-EFAULT);
 322         r->ur_namelen = req->rq_reqmsg->buflens[offset + 1];
 323
 324         LASSERT_REQSWAB (req, offset + 2);
 325         if (req->rq_reqmsg->bufcount > offset + 2) {
 326                 if (S_ISLNK(r->ur_mode)) {
 327                         r->ur_tgt = lustre_msg_string(req->rq_reqmsg,
 328                                                       offset + 2, 0);
 329                         if (r->ur_tgt == NULL)
 330                                 RETURN (-EFAULT);
 331                         r->ur_tgtlen = req->rq_reqmsg->buflens[offset + 2];
 332                 } else if (S_ISDIR(r->ur_mode)) {
 333                         /* Stripe info for mkdir - just a 16bit integer */
 334                         if (req->rq_reqmsg->buflens[offset + 2] != 2) {
 335                                 CERROR("mkdir stripe info does not match "
 336                                        "expected size %d vs 2\n",
 337                                        req->rq_reqmsg->buflens[offset + 2]);
 338                                 RETURN (-EINVAL);
 339                         }
 340                         r->ur_eadata = lustre_swab_buf (req->rq_reqmsg,
 341                                                offset + 2, 2, __swab16s);
 342                         r->ur_eadatalen = req->rq_reqmsg->buflens[offset + 2];
 343                 } else {
 344                         /* Hm, no other users so far? */
 345                         LBUG();
 346                 }
 347         }
 348         RETURN(0);
 349 }
 350
 351 static int mds_link_unpack(struct ptlrpc_request *req, int offset,
 352                            struct mds_update_record *r)
 353 {
 354         struct mds_rec_link *rec;
 355         ENTRY;
 356
 357         rec = lustre_swab_reqbuf (req, offset, sizeof (*rec),
 358                                   lustre_swab_mds_rec_link);
 359         if (rec == NULL)
 360                 RETURN (-EFAULT);
 361
 362         r->ur_id1 = &rec->lk_id1;
 363         r->ur_id2 = &rec->lk_id2;
 364         r->ur_time = rec->lk_time;
 365
 366         LASSERT_REQSWAB (req, offset + 1);
 367         r->ur_name = lustre_msg_string (req->rq_reqmsg, offset + 1, 0);
 368         if (r->ur_name == NULL)
 369                 RETURN (-EFAULT);
 370         r->ur_namelen = req->rq_reqmsg->buflens[offset + 1];
 371         RETURN(0);
 372 }
 373
 374 static int mds_unlink_unpack(struct ptlrpc_request *req, int offset,
 375                              struct mds_update_record *r)
 376 {
 377         struct mds_rec_unlink *rec;
 378         ENTRY;
 379
 380         rec = lustre_swab_reqbuf (req, offset, sizeof (*rec),
 381                                   lustre_swab_mds_rec_unlink);
 382         if (rec == NULL)
 383                 RETURN(-EFAULT);
 384
 385         r->ur_mode = rec->ul_mode;
 386         r->ur_id1 = &rec->ul_id1;
 387         r->ur_id2 = &rec->ul_id2;
 388         r->ur_time = rec->ul_time;
 389
 390         LASSERT_REQSWAB (req, offset + 1);
 391         r->ur_name = lustre_msg_string(req->rq_reqmsg, offset + 1, 0);
 392         if (r->ur_name == NULL)
 393                 RETURN(-EFAULT);
 394         r->ur_namelen = req->rq_reqmsg->buflens[offset + 1];
 395         RETURN(0);
 396 }
 397
 398 static int mds_rename_unpack(struct ptlrpc_request *req, int offset,
 399                              struct mds_update_record *r)
 400 {
 401         struct mds_rec_rename *rec;
 402         ENTRY;
 403
 404         rec = lustre_swab_reqbuf (req, offset, sizeof (*rec),
 405                                   lustre_swab_mds_rec_rename);
 406         if (rec == NULL)
 407                 RETURN(-EFAULT);
 408
 409         r->ur_id1 = &rec->rn_id1;
 410         r->ur_id2 = &rec->rn_id2;
 411         r->ur_time = rec->rn_time;
 412
 413         LASSERT_REQSWAB (req, offset + 1);
 414         r->ur_name = lustre_msg_string(req->rq_reqmsg, offset + 1, 0);
 415         if (r->ur_name == NULL)
 416                 RETURN(-EFAULT);
 417         r->ur_namelen = req->rq_reqmsg->buflens[offset + 1];
 418
 419         LASSERT_REQSWAB (req, offset + 2);
 420         r->ur_tgt = lustre_msg_string(req->rq_reqmsg, offset + 2, 0);
 421         if (r->ur_tgt == NULL)
 422                 RETURN(-EFAULT);
 423         r->ur_tgtlen = req->rq_reqmsg->buflens[offset + 2];
 424         RETURN(0);
 425 }
 426
 427 static int mds_open_unpack(struct ptlrpc_request *req, int offset,
 428                            struct mds_update_record *r)
 429 {
 430         struct mds_rec_create *rec;
 431         ENTRY;
 432
 433         rec = lustre_swab_reqbuf (req, offset, sizeof (*rec),
 434                                   lustre_swab_mds_rec_create);
 435         if (rec == NULL)
 436                 RETURN(-EFAULT);
 437
 438         r->ur_id1 = &rec->cr_id;
 439         r->ur_id2 = &rec->cr_replayid;
 440         r->ur_mode = rec->cr_mode;
 441         r->ur_rdev = rec->cr_rdev;
 442         r->ur_time = rec->cr_time;
 443         r->ur_flags = rec->cr_flags;
 444
 445         LASSERT_REQSWAB (req, offset + 1);
 446         r->ur_name = lustre_msg_string (req->rq_reqmsg, offset + 1, 0);
 447         if (r->ur_name == NULL)
 448                 RETURN (-EFAULT);
 449         r->ur_namelen = req->rq_reqmsg->buflens[offset + 1];
 450
 451         LASSERT_REQSWAB (req, offset + 2);
 452         if (req->rq_reqmsg->bufcount > offset + 2) {
 453                 r->ur_eadata = lustre_msg_buf(req->rq_reqmsg, offset + 2, 0);
 454                 if (r->ur_eadata == NULL)
 455                         RETURN(-EFAULT);
 456                 r->ur_eadatalen = req->rq_reqmsg->buflens[offset + 2];
 457         }
 458         RETURN(0);
 459 }
 460
 461 typedef int (*update_unpacker)(struct ptlrpc_request *req, int offset,
 462                                struct mds_update_record *r);
 463
 464 static update_unpacker mds_unpackers[REINT_MAX + 1] = {
 465         [REINT_SETATTR] mds_setattr_unpack,
 466         [REINT_CREATE] mds_create_unpack,
 467         [REINT_LINK] mds_link_unpack,
 468         [REINT_UNLINK] mds_unlink_unpack,
 469         [REINT_RENAME] mds_rename_unpack,
 470         [REINT_OPEN] mds_open_unpack,
 471 };
 472
 473 int mds_update_unpack(struct ptlrpc_request *req, int offset,
 474                       struct mds_update_record *rec)
 475 {
 476         __u32 *opcodep;
 477         __u32  opcode;
 478         int rc;
 479         ENTRY;
 480
 481         /*
 482          * NB don't lustre_swab_reqbuf() here. We're just taking a peek and we
 483          * want to leave it to the specific unpacker once we've identified the
 484          * message type.
 485          */
 486         opcodep = lustre_msg_buf (req->rq_reqmsg, offset, sizeof(*opcodep));
 487         if (opcodep == NULL)
 488                 RETURN(-EFAULT);
 489
 490         opcode = *opcodep;
 491         if (lustre_msg_swabbed (req->rq_reqmsg))
 492                 __swab32s (&opcode);
 493
 494         if (opcode > REINT_MAX ||
 495             mds_unpackers[opcode] == NULL) {
 496                 CERROR ("Unexpected opcode %d\n", opcode);
 497                 RETURN(-EFAULT);
 498         }
 499
 500         rec->ur_id1 = NULL;
 501         rec->ur_id2 = NULL;
 502         rec->ur_opcode = opcode;
 503
 504         rc = mds_unpackers[opcode](req, offset, rec);
 505
 506 #if CRAY_PORTALS
 507         rec->ur_fsuid = req->rq_uid;
 508 #endif
 509         RETURN(rc);
 510 }
 511
 512 /********************************
 513  * MDS uid/gid mapping handling *
 514  ********************************/
 515
 516 static
 517 struct mds_idmap_entry* idmap_alloc_entry(__u32 rmt_id, __u32 lcl_id)
 518 {
 519         struct mds_idmap_entry *e;
 520
 521         OBD_ALLOC(e, sizeof(*e));
 522         if (!e)
 523                 return NULL;
 524
 525         INIT_LIST_HEAD(&e->rmt_hash);
 526         INIT_LIST_HEAD(&e->lcl_hash);
 527         atomic_set(&e->refcount, 1);
 528         e->rmt_id = rmt_id;
 529         e->lcl_id = lcl_id;
 530
 531         return e;
 532 }
 533
 534 void idmap_free_entry(struct mds_idmap_entry *e)
 535 {
 536         if (!list_empty(&e->rmt_hash))
 537                 list_del(&e->rmt_hash);
 538         if (!list_empty(&e->lcl_hash))
 539                 list_del(&e->lcl_hash);
 540         OBD_FREE(e, sizeof(*e));
 541 }
 542
 543 static
 544 int idmap_insert_entry(struct list_head *rmt_hash, struct list_head *lcl_hash,
 545                        struct mds_idmap_entry *new, const char *warn_msg)
 546 {
 547         struct list_head *rmt_head = &rmt_hash[MDS_IDMAP_HASHFUNC(new->rmt_id)];
 548         struct list_head *lcl_head = &lcl_hash[MDS_IDMAP_HASHFUNC(new->lcl_id)];
 549         struct mds_idmap_entry *e;
 550
 551         list_for_each_entry(e, rmt_head, rmt_hash) {
 552                 if (e->rmt_id == new->rmt_id &&
 553                     e->lcl_id == new->lcl_id) {
 554                         atomic_inc(&e->refcount);
 555                         return 1;
 556                 }
 557                 if (e->rmt_id == new->rmt_id && warn_msg)
 558                         CWARN("%s: rmt id %u already map to %u (new %u)\n",
 559                               warn_msg, e->rmt_id, e->lcl_id, new->lcl_id);
 560                 if (e->lcl_id == new->lcl_id && warn_msg)
 561                         CWARN("%s: lcl id %u already be mapped from %u "
 562                               "(new %u)\n", warn_msg,
 563                               e->lcl_id, e->rmt_id, new->rmt_id);
 564         }
 565
 566         list_add_tail(rmt_head, &new->rmt_hash);
 567         list_add_tail(lcl_head, &new->lcl_hash);
 568         return 0;
 569 }
 570
 571 static
 572 int idmap_remove_entry(struct list_head *rmt_hash, struct list_head *lcl_hash,
 573                        __u32 rmt_id, __u32 lcl_id)
 574 {
 575         struct list_head *rmt_head = &rmt_hash[MDS_IDMAP_HASHFUNC(rmt_id)];
 576         struct mds_idmap_entry *e;
 577
 578         list_for_each_entry(e, rmt_head, rmt_hash) {
 579                 if (e->rmt_id == rmt_id && e->lcl_id == lcl_id) {
 580                         if (atomic_dec_and_test(&e->refcount)) {
 581                                 list_del(&e->rmt_hash);
 582                                 list_del(&e->lcl_hash);
 583                                 OBD_FREE(e, sizeof(*e));
 584                                 return 0;
 585                         } else
 586                                 return 1;
 587                 }
 588         }
 589         return -ENOENT;
 590 }
 591
 592 int mds_idmap_add(struct mds_idmap_table *tbl,
 593                   uid_t rmt_uid, uid_t lcl_uid,
 594                   gid_t rmt_gid, gid_t lcl_gid)
 595 {
 596         struct mds_idmap_entry *ue, *ge;
 597         ENTRY;
 598
 599         if (!tbl)
 600                 RETURN(-EPERM);
 601
 602         ue = idmap_alloc_entry(rmt_uid, lcl_uid);
 603         if (!ue)
 604                 RETURN(-ENOMEM);
 605         ge = idmap_alloc_entry(rmt_gid, lcl_gid);
 606         if (!ge) {
 607                 idmap_free_entry(ue);
 608                 RETURN(-ENOMEM);
 609         }
 610
 611         spin_lock(&tbl->mit_lock);
 612
 613         if (idmap_insert_entry(tbl->mit_idmaps[MDS_RMT_UIDMAP_IDX],
 614                                tbl->mit_idmaps[MDS_LCL_UIDMAP_IDX],
 615                                ue, "UID mapping")) {
 616                 idmap_free_entry(ue);
 617         }
 618
 619         if (idmap_insert_entry(tbl->mit_idmaps[MDS_RMT_GIDMAP_IDX],
 620                                tbl->mit_idmaps[MDS_LCL_GIDMAP_IDX],
 621                                ge, "GID mapping")) {
 622                 idmap_free_entry(ge);
 623         }
 624
 625         spin_unlock(&tbl->mit_lock);
 626         RETURN(0);
 627 }
 628
 629 int mds_idmap_del(struct mds_idmap_table *tbl,
 630                   uid_t rmt_uid, uid_t lcl_uid,
 631                   gid_t rmt_gid, gid_t lcl_gid)
 632 {
 633         ENTRY;
 634
 635         if (!tbl)
 636                 RETURN(0);
 637
 638         spin_lock(&tbl->mit_lock);
 639         idmap_remove_entry(tbl->mit_idmaps[MDS_RMT_UIDMAP_IDX],
 640                            tbl->mit_idmaps[MDS_LCL_UIDMAP_IDX],
 641                            rmt_uid, lcl_uid);
 642         idmap_remove_entry(tbl->mit_idmaps[MDS_RMT_GIDMAP_IDX],
 643                            tbl->mit_idmaps[MDS_LCL_GIDMAP_IDX],
 644                            rmt_gid, lcl_gid);
 645         spin_unlock(&tbl->mit_lock);
 646         RETURN(0);
 647 }
 648
 649 static
 650 __u32 idmap_lookup_id(struct list_head *hash, int reverse, __u32 id)
 651 {
 652         struct list_head *head = &hash[MDS_IDMAP_HASHFUNC(id)];
 653         struct mds_idmap_entry *e;
 654
 655         if (!reverse) {
 656                 list_for_each_entry(e, head, rmt_hash) {
 657                         if (e->rmt_id == id)
 658                                 return e->lcl_id;
 659                 }
 660                 return MDS_IDMAP_NOTFOUND;
 661         } else {
 662                 list_for_each_entry(e, head, lcl_hash) {
 663                         if (e->lcl_id == id)
 664                                 return e->rmt_id;
 665                 }
 666                 return MDS_IDMAP_NOTFOUND;
 667         }
 668 }
 669
 670 int mds_idmap_lookup_uid(struct mds_idmap_table *tbl, int reverse, uid_t uid)
 671 {
 672         struct list_head *hash;
 673
 674         if (!tbl)
 675                 return MDS_IDMAP_NOTFOUND;
 676
 677         if (!reverse)
 678                 hash = tbl->mit_idmaps[MDS_RMT_UIDMAP_IDX];
 679         else
 680                 hash = tbl->mit_idmaps[MDS_LCL_UIDMAP_IDX];
 681
 682         spin_lock(&tbl->mit_lock);
 683         uid = idmap_lookup_id(hash, reverse, uid);
 684         spin_unlock(&tbl->mit_lock);
 685
 686         return uid;
 687 }
 688
 689 int mds_idmap_lookup_gid(struct mds_idmap_table *tbl, int reverse, gid_t gid)
 690 {
 691         struct list_head *hash;
 692
 693         if (!tbl)
 694                 return MDS_IDMAP_NOTFOUND;
 695
 696         if (!reverse)
 697                 hash = tbl->mit_idmaps[MDS_RMT_GIDMAP_IDX];
 698         else
 699                 hash = tbl->mit_idmaps[MDS_LCL_GIDMAP_IDX];
 700
 701         spin_lock(&tbl->mit_lock);
 702         gid = idmap_lookup_id(hash, reverse, gid);
 703         spin_unlock(&tbl->mit_lock);
 704
 705         return gid;
 706 }
 707
 708 struct mds_idmap_table *mds_idmap_alloc()
 709 {
 710         struct mds_idmap_table *tbl;
 711         int i, j;
 712
 713         OBD_ALLOC(tbl, sizeof(*tbl));
 714         if (!tbl)
 715                 return NULL;
 716
 717         spin_lock_init(&tbl->mit_lock);
 718         for (i = 0; i < MDS_IDMAP_N_HASHES; i++)
 719                 for (j = 0; j < MDS_IDMAP_HASHSIZE; j++)
 720                         INIT_LIST_HEAD(&tbl->mit_idmaps[i][j]);
 721
 722         return tbl;
 723 }
 724
 725 static void idmap_clear_rmt_hash(struct list_head *list)
 726 {
 727         struct mds_idmap_entry *e;
 728         int i;
 729
 730         for (i = 0; i < MDS_IDMAP_HASHSIZE; i++) {
 731                 while (!list_empty(&list[i])) {
 732                         e = list_entry(list[i].next, struct mds_idmap_entry,
 733                                        rmt_hash);
 734                         idmap_free_entry(e);
 735                 }
 736         }
 737 }
 738
 739 void mds_idmap_free(struct mds_idmap_table *tbl)
 740 {
 741         int i;
 742
 743         spin_lock(&tbl->mit_lock);
 744         idmap_clear_rmt_hash(tbl->mit_idmaps[MDS_RMT_UIDMAP_IDX]);
 745         idmap_clear_rmt_hash(tbl->mit_idmaps[MDS_RMT_GIDMAP_IDX]);
 746
 747         /* paranoid checking */
 748         for (i = 0; i < MDS_IDMAP_HASHSIZE; i++) {
 749                 LASSERT(list_empty(&tbl->mit_idmaps[MDS_LCL_UIDMAP_IDX][i]));
 750                 LASSERT(list_empty(&tbl->mit_idmaps[MDS_LCL_GIDMAP_IDX][i]));
 751         }
 752         spin_unlock(&tbl->mit_lock);
 753
 754         OBD_FREE(tbl, sizeof(*tbl));
 755 }
 756
 757 /*********************************
 758  * helpers doing mapping for MDS *
 759  *********************************/
 760
 761 /*
 762  * we allow remote setuid/setgid to an "authencated" one,
 763  * this policy probably change later.
 764  */
 765 static
 766 int mds_req_secdesc_do_map(struct mds_export_data *med,
 767                            struct mds_req_sec_desc *rsd)
 768 {
 769         struct mds_idmap_table *idmap = med->med_idmap;
 770         uid_t uid, fsuid;
 771         gid_t gid, fsgid;
 772
 773         uid = mds_idmap_lookup_uid(idmap, 0, rsd->rsd_uid);
 774         if (uid == MDS_IDMAP_NOTFOUND) {
 775                 CERROR("can't find map for uid %u\n", rsd->rsd_uid);
 776                 return -EPERM;
 777         }
 778
 779         if (rsd->rsd_uid == rsd->rsd_fsuid)
 780                 fsuid = uid;
 781         else {
 782                 fsuid = mds_idmap_lookup_uid(idmap, 0, rsd->rsd_fsuid);
 783                 if (fsuid == MDS_IDMAP_NOTFOUND) {
 784                         CERROR("can't find map for fsuid %u\n", rsd->rsd_fsuid);
 785                         return -EPERM;
 786                 }
 787         }
 788
 789         gid = mds_idmap_lookup_gid(idmap, 0, rsd->rsd_gid);
 790         if (gid == MDS_IDMAP_NOTFOUND) {
 791                 CERROR("can't find map for gid %u\n", rsd->rsd_gid);
 792                 return -EPERM;
 793         }
 794
 795         if (rsd->rsd_gid == rsd->rsd_fsgid)
 796                 fsgid = gid;
 797         else {
 798                 fsgid = mds_idmap_lookup_gid(idmap, 0, rsd->rsd_fsgid);
 799                 if (fsgid == MDS_IDMAP_NOTFOUND) {
 800                         CERROR("can't find map for fsgid %u\n", rsd->rsd_fsgid);
 801                         return -EPERM;
 802                 }
 803         }
 804
 805         rsd->rsd_uid = uid;
 806         rsd->rsd_gid = gid;
 807         rsd->rsd_fsuid = fsuid;
 808         rsd->rsd_fsgid = fsgid;
 809
 810         return 0;
 811 }
 812
 813 void mds_body_do_reverse_map(struct mds_export_data *med,
 814                              struct mds_body *body)
 815 {
 816         uid_t uid;
 817         gid_t gid;
 818
 819         if (!med->med_remote)
 820                 return;
 821
 822         ENTRY;
 823         if (body->valid & OBD_MD_FLUID) {
 824                 uid = mds_idmap_lookup_uid(med->med_idmap, 1, body->uid);
 825                 if (uid == MDS_IDMAP_NOTFOUND) {
 826                         uid = med->med_nllu;
 827                         if (body->valid & OBD_MD_FLMODE) {
 828                                 body->mode = (body->mode & ~S_IRWXU) |
 829                                              ((body->mode & S_IRWXO) << 6);
 830                         }
 831                 }
 832                 body->uid = uid;
 833         }
 834         if (body->valid & OBD_MD_FLGID) {
 835                 gid = mds_idmap_lookup_gid(med->med_idmap, 1, body->gid);
 836                 if (gid == MDS_IDMAP_NOTFOUND) {
 837                         gid = med->med_nllg;
 838                         if (body->valid & OBD_MD_FLMODE) {
 839                                 body->mode = (body->mode & ~S_IRWXG) |
 840                                              ((body->mode & S_IRWXO) << 3);
 841                         }
 842                 }
 843                 body->gid = gid;
 844         }
 845
 846         EXIT;
 847 }
 848
 849 /**********************
 850  * MDS ucred handling *
 851  **********************/
 852
 853 static inline void drop_ucred_ginfo(struct lvfs_ucred *ucred)
 854 {
 855         if (ucred->luc_ginfo) {
 856                 put_group_info(ucred->luc_ginfo);
 857                 ucred->luc_ginfo = NULL;
 858         }
 859 }
 860
 861 static inline void drop_ucred_lsd(struct lvfs_ucred *ucred)
 862 {
 863         if (ucred->luc_lsd) {
 864                 mds_put_lsd(ucred->luc_lsd);
 865                 ucred->luc_lsd = NULL;
 866         }
 867 }
 868
 869 /*
 870  * the heart of the uid/gid handling and security checking.
 871  *
 872  * root could set any group_info if we allowed setgroups, while
 873  * normal user only could 'reduce' their group members -- which
 874  * is somewhat expensive.
 875  */
 876 int mds_init_ucred(struct lvfs_ucred *ucred,
 877                    struct ptlrpc_request *req,
 878                    struct mds_req_sec_desc *rsd)
 879 {
 880         struct mds_obd *mds = &req->rq_export->exp_obd->u.mds;
 881         struct mds_export_data *med = &req->rq_export->u.eu_mds_data;
 882         struct lustre_sec_desc *lsd;
 883         ptl_nid_t peernid = req->rq_peer.peer_id.nid;
 884         struct group_info *gnew;
 885         unsigned int setuid, setgid, strong_sec, root_squashed;
 886         __u32 lsd_perms;
 887         ENTRY;
 888
 889         LASSERT(ucred);
 890         LASSERT(rsd);
 891         LASSERT(rsd->rsd_ngroups <= LUSTRE_MAX_GROUPS);
 892
 893         strong_sec = (req->rq_auth_uid != -1);
 894         LASSERT(!(req->rq_remote_realm && !strong_sec));
 895
 896         /* if we use strong authentication for a local client, we
 897          * expect the uid which client claimed is true.
 898          */
 899         if (!med->med_remote && strong_sec &&
 900             req->rq_auth_uid != rsd->rsd_uid) {
 901                 CWARN("nid "LPX64": UID %u was authenticated while client "
 902                       "claimed %u, enforce to be %u\n",
 903                       peernid, req->rq_auth_uid, rsd->rsd_uid,
 904                       req->rq_auth_uid);
 905                 if (rsd->rsd_uid != rsd->rsd_fsuid)
 906                         rsd->rsd_uid = req->rq_auth_uid;
 907                 else
 908                         rsd->rsd_uid = rsd->rsd_fsuid = req->rq_auth_uid;
 909         }
 910
 911         if (med->med_remote) {
 912                 int rc;
 913
 914                 if (req->rq_mapped_uid == MDS_IDMAP_NOTFOUND) {
 915                         CWARN("no mapping found, deny\n");
 916                         RETURN(-EPERM);
 917                 }
 918
 919                 rc = mds_req_secdesc_do_map(med, rsd);
 920                 if (rc)
 921                         RETURN(rc);
 922         }
 923
 924         /* now lsd come into play */
 925         ucred->luc_ginfo = NULL;
 926         ucred->luc_lsd = lsd = mds_get_lsd(rsd->rsd_uid);
 927
 928         if (!lsd) {
 929                 CERROR("Deny access without LSD: uid %d\n", rsd->rsd_uid);
 930                 RETURN(-EPERM);
 931         }
 932
 933         /* find out the setuid/setgid attempt */
 934         setuid = (rsd->rsd_uid != rsd->rsd_fsuid);
 935         setgid = (rsd->rsd_gid != rsd->rsd_fsgid ||
 936                   rsd->rsd_gid != lsd->lsd_gid);
 937
 938         lsd_perms = mds_lsd_get_perms(lsd, med->med_remote, 0, peernid);
 939
 940         /* check permission of setuid */
 941         if (setuid && !(lsd_perms & LSD_PERM_SETUID)) {
 942                 CWARN("mds blocked setuid attempt: %u -> %u\n",
 943                       rsd->rsd_uid, rsd->rsd_fsuid);
 944                 RETURN(-EPERM);
 945         }
 946
 947         /* check permission of setgid */
 948         if (setgid && !(lsd_perms & LSD_PERM_SETGID)) {
 949                 CWARN("mds blocked setgid attempt: %u -> %u\n",
 950                       rsd->rsd_gid, rsd->rsd_fsgid);
 951                 RETURN(-EPERM);
 952         }
 953
 954         root_squashed = mds_squash_root(mds, rsd, &peernid);
 955
 956         /* remove privilege for non-root user */
 957         if (rsd->rsd_fsuid)
 958                 rsd->rsd_cap &= ~CAP_FS_MASK;
 959
 960         /* by now every fields other than groups in rsd have been granted */
 961         ucred->luc_uid = rsd->rsd_uid;
 962         ucred->luc_gid = rsd->rsd_gid;
 963         ucred->luc_fsuid = rsd->rsd_fsuid;
 964         ucred->luc_fsgid = rsd->rsd_fsgid;
 965         ucred->luc_cap = rsd->rsd_cap;
 966
 967         /* don't use any supplementary group for remote client or
 968          * we squashed root */
 969         if (med->med_remote || root_squashed)
 970                 RETURN(0);
 971
 972         /* install groups from LSD */
 973         if (lsd->lsd_ginfo) {
 974                 ucred->luc_ginfo = lsd->lsd_ginfo;
 975                 get_group_info(ucred->luc_ginfo);
 976         }
 977
 978         /* everything is done if we don't allow setgroups */
 979         if (!(lsd_perms & LSD_PERM_SETGRP))
 980                 RETURN(0);
 981
 982         /* root could set any groups as he want (if allowed), normal
 983          * users only could reduce his group array.
 984          */
 985         if (ucred->luc_uid == 0) {
 986                 drop_ucred_ginfo(ucred);
 987
 988                 if (rsd->rsd_ngroups == 0)
 989                         RETURN(0);
 990
 991                 gnew = groups_alloc(rsd->rsd_ngroups);
 992                 if (!gnew) {
 993                         CERROR("out of memory\n");
 994                         drop_ucred_lsd(ucred);
 995                         RETURN(-ENOMEM);
 996                 }
 997                 groups_from_buffer(gnew, rsd->rsd_groups);
 998                 groups_sort(gnew); /* don't rely on client doing this */
 999
1000                 ucred->luc_ginfo = gnew;
1001         } else {
1002                 __u32 set = 0, cur = 0;
1003                 struct group_info *ginfo = ucred->luc_ginfo;
1004
1005                 if (!ginfo)
1006                         RETURN(0);
1007
1008                 /* Note: freeing a group_info count on 'nblocks' instead of
1009                  * 'ngroups', thus we can safely alloc enough buffer and reduce
1010                  * and ngroups number later.
1011                  */
1012                 gnew = groups_alloc(rsd->rsd_ngroups);
1013                 if (!gnew) {
1014                         CERROR("out of memory\n");
1015                         drop_ucred_ginfo(ucred);
1016                         drop_ucred_lsd(ucred);
1017                         RETURN(-ENOMEM);
1018                 }
1019
1020                 while (cur < rsd->rsd_ngroups) {
1021                         if (groups_search(ginfo, rsd->rsd_groups[cur])) {
1022                                 GROUP_AT(gnew, set) = rsd->rsd_groups[cur];
1023                                 set++;
1024                         }
1025                         cur++;
1026                 }
1027                 gnew->ngroups = set;
1028
1029                 put_group_info(ucred->luc_ginfo);
1030                 ucred->luc_ginfo = gnew;
1031         }
1032         RETURN(0);
1033 }
1034
1035 void mds_exit_ucred(struct lvfs_ucred *ucred)
1036 {
1037         ENTRY;
1038         drop_ucred_ginfo(ucred);
1039         drop_ucred_lsd(ucred);
1040         EXIT;
1041 }