fs/nfs/idmap.c

   1 /*
   2  * fs/nfs/idmap.c
   3  *
   4  *  UID and GID to name mapping for clients.
   5  *
   6  *  Copyright (c) 2002 The Regents of the University of Michigan.
   7  *  All rights reserved.
   8  *
   9  *  Marius Aamodt Eriksen <marius@umich.edu>
  10  *
  11  *  Redistribution and use in source and binary forms, with or without
  12  *  modification, are permitted provided that the following conditions
  13  *  are met:
  14  *
  15  *  1. Redistributions of source code must retain the above copyright
  16  *     notice, this list of conditions and the following disclaimer.
  17  *  2. Redistributions in binary form must reproduce the above copyright
  18  *     notice, this list of conditions and the following disclaimer in the
  19  *     documentation and/or other materials provided with the distribution.
  20  *  3. Neither the name of the University nor the names of its
  21  *     contributors may be used to endorse or promote products derived
  22  *     from this software without specific prior written permission.
  23  *
  24  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  25  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  26  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  27  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  29  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  30  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  31  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  32  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  33  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  34  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35  */
  36 #include <linux/types.h>
  37 #include <linux/parser.h>
  38 #include <linux/fs.h>
  39 #include <linux/nfs_idmap.h>
  40 #include <net/net_namespace.h>
  41 #include <linux/sunrpc/rpc_pipe_fs.h>
  42 #include <linux/nfs_fs.h>
  43 #include <linux/nfs_fs_sb.h>
  44 #include <linux/key.h>
  45 #include <linux/keyctl.h>
  46 #include <linux/key-type.h>
  47 #include <keys/user-type.h>
  48 #include <linux/module.h>
  49
  50 #include "internal.h"
  51 #include "netns.h"
  52 #include "nfs4trace.h"
  53
  54 #define NFS_UINT_MAXLEN 11
  55
  56 static const struct cred *id_resolver_cache;
  57 static struct key_type key_type_id_resolver_legacy;
  58
  59 struct idmap_legacy_upcalldata {
  60         struct rpc_pipe_msg pipe_msg;
  61         struct idmap_msg idmap_msg;
  62         struct key_construction *key_cons;
  63         struct idmap *idmap;
  64 };
  65
  66 struct idmap {
  67         struct rpc_pipe_dir_object idmap_pdo;
  68         struct rpc_pipe         *idmap_pipe;
  69         struct idmap_legacy_upcalldata *idmap_upcall_data;
  70         struct mutex            idmap_mutex;
  71 };
  72
  73 /**
  74  * nfs_fattr_init_names - initialise the nfs_fattr owner_name/group_name fields
  75  * @fattr: fully initialised struct nfs_fattr
  76  * @owner_name: owner name string cache
  77  * @group_name: group name string cache
  78  */
  79 void nfs_fattr_init_names(struct nfs_fattr *fattr,
  80                 struct nfs4_string *owner_name,
  81                 struct nfs4_string *group_name)
  82 {
  83         fattr->owner_name = owner_name;
  84         fattr->group_name = group_name;
  85 }
  86
  87 static void nfs_fattr_free_owner_name(struct nfs_fattr *fattr)
  88 {
  89         fattr->valid &= ~NFS_ATTR_FATTR_OWNER_NAME;
  90         kfree(fattr->owner_name->data);
  91 }
  92
  93 static void nfs_fattr_free_group_name(struct nfs_fattr *fattr)
  94 {
  95         fattr->valid &= ~NFS_ATTR_FATTR_GROUP_NAME;
  96         kfree(fattr->group_name->data);
  97 }
  98
  99 static bool nfs_fattr_map_owner_name(struct nfs_server *server, struct nfs_fattr *fattr)
 100 {
 101         struct nfs4_string *owner = fattr->owner_name;
 102         kuid_t uid;
 103
 104         if (!(fattr->valid & NFS_ATTR_FATTR_OWNER_NAME))
 105                 return false;
 106         if (nfs_map_name_to_uid(server, owner->data, owner->len, &uid) == 0) {
 107                 fattr->uid = uid;
 108                 fattr->valid |= NFS_ATTR_FATTR_OWNER;
 109         }
 110         return true;
 111 }
 112
 113 static bool nfs_fattr_map_group_name(struct nfs_server *server, struct nfs_fattr *fattr)
 114 {
 115         struct nfs4_string *group = fattr->group_name;
 116         kgid_t gid;
 117
 118         if (!(fattr->valid & NFS_ATTR_FATTR_GROUP_NAME))
 119                 return false;
 120         if (nfs_map_group_to_gid(server, group->data, group->len, &gid) == 0) {
 121                 fattr->gid = gid;
 122                 fattr->valid |= NFS_ATTR_FATTR_GROUP;
 123         }
 124         return true;
 125 }
 126
 127 /**
 128  * nfs_fattr_free_names - free up the NFSv4 owner and group strings
 129  * @fattr: a fully initialised nfs_fattr structure
 130  */
 131 void nfs_fattr_free_names(struct nfs_fattr *fattr)
 132 {
 133         if (fattr->valid & NFS_ATTR_FATTR_OWNER_NAME)
 134                 nfs_fattr_free_owner_name(fattr);
 135         if (fattr->valid & NFS_ATTR_FATTR_GROUP_NAME)
 136                 nfs_fattr_free_group_name(fattr);
 137 }
 138
 139 /**
 140  * nfs_fattr_map_and_free_names - map owner/group strings into uid/gid and free
 141  * @server: pointer to the filesystem nfs_server structure
 142  * @fattr: a fully initialised nfs_fattr structure
 143  *
 144  * This helper maps the cached NFSv4 owner/group strings in fattr into
 145  * their numeric uid/gid equivalents, and then frees the cached strings.
 146  */
 147 void nfs_fattr_map_and_free_names(struct nfs_server *server, struct nfs_fattr *fattr)
 148 {
 149         if (nfs_fattr_map_owner_name(server, fattr))
 150                 nfs_fattr_free_owner_name(fattr);
 151         if (nfs_fattr_map_group_name(server, fattr))
 152                 nfs_fattr_free_group_name(fattr);
 153 }
 154
 155 static int nfs_map_string_to_numeric(const char *name, size_t namelen, __u32 *res)
 156 {
 157         unsigned long val;
 158         char buf[16];
 159
 160         if (memchr(name, '@', namelen) != NULL || namelen >= sizeof(buf))
 161                 return 0;
 162         memcpy(buf, name, namelen);
 163         buf[namelen] = '\0';
 164         if (kstrtoul(buf, 0, &val) != 0)
 165                 return 0;
 166         *res = val;
 167         return 1;
 168 }
 169
 170 static int nfs_map_numeric_to_string(__u32 id, char *buf, size_t buflen)
 171 {
 172         return snprintf(buf, buflen, "%u", id);
 173 }
 174
 175 static struct key_type key_type_id_resolver = {
 176         .name           = "id_resolver",
 177         .instantiate    = user_instantiate,
 178         .match          = user_match,
 179         .revoke         = user_revoke,
 180         .destroy        = user_destroy,
 181         .describe       = user_describe,
 182         .read           = user_read,
 183 };
 184
 185 static int nfs_idmap_init_keyring(void)
 186 {
 187         struct cred *cred;
 188         struct key *keyring;
 189         int ret = 0;
 190
 191         printk(KERN_NOTICE "NFS: Registering the %s key type\n",
 192                 key_type_id_resolver.name);
 193
 194         cred = prepare_kernel_cred(NULL);
 195         if (!cred)
 196                 return -ENOMEM;
 197
 198         keyring = keyring_alloc(".id_resolver",
 199                                 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
 200                                 (KEY_POS_ALL & ~KEY_POS_SETATTR) |
 201                                 KEY_USR_VIEW | KEY_USR_READ,
 202                                 KEY_ALLOC_NOT_IN_QUOTA, NULL);
 203         if (IS_ERR(keyring)) {
 204                 ret = PTR_ERR(keyring);
 205                 goto failed_put_cred;
 206         }
 207
 208         ret = register_key_type(&key_type_id_resolver);
 209         if (ret < 0)
 210                 goto failed_put_key;
 211
 212         ret = register_key_type(&key_type_id_resolver_legacy);
 213         if (ret < 0)
 214                 goto failed_reg_legacy;
 215
 216         set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags);
 217         cred->thread_keyring = keyring;
 218         cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING;
 219         id_resolver_cache = cred;
 220         return 0;
 221
 222 failed_reg_legacy:
 223         unregister_key_type(&key_type_id_resolver);
 224 failed_put_key:
 225         key_put(keyring);
 226 failed_put_cred:
 227         put_cred(cred);
 228         return ret;
 229 }
 230
 231 static void nfs_idmap_quit_keyring(void)
 232 {
 233         key_revoke(id_resolver_cache->thread_keyring);
 234         unregister_key_type(&key_type_id_resolver);
 235         unregister_key_type(&key_type_id_resolver_legacy);
 236         put_cred(id_resolver_cache);
 237 }
 238
 239 /*
 240  * Assemble the description to pass to request_key()
 241  * This function will allocate a new string and update dest to point
 242  * at it.  The caller is responsible for freeing dest.
 243  *
 244  * On error 0 is returned.  Otherwise, the length of dest is returned.
 245  */
 246 static ssize_t nfs_idmap_get_desc(const char *name, size_t namelen,
 247                                 const char *type, size_t typelen, char **desc)
 248 {
 249         char *cp;
 250         size_t desclen = typelen + namelen + 2;
 251
 252         *desc = kmalloc(desclen, GFP_KERNEL);
 253         if (!*desc)
 254                 return -ENOMEM;
 255
 256         cp = *desc;
 257         memcpy(cp, type, typelen);
 258         cp += typelen;
 259         *cp++ = ':';
 260
 261         memcpy(cp, name, namelen);
 262         cp += namelen;
 263         *cp = '\0';
 264         return desclen;
 265 }
 266
 267 static struct key *nfs_idmap_request_key(const char *name, size_t namelen,
 268                                          const char *type, struct idmap *idmap)
 269 {
 270         char *desc;
 271         struct key *rkey;
 272         ssize_t ret;
 273
 274         ret = nfs_idmap_get_desc(name, namelen, type, strlen(type), &desc);
 275         if (ret <= 0)
 276                 return ERR_PTR(ret);
 277
 278         rkey = request_key(&key_type_id_resolver, desc, "");
 279         if (IS_ERR(rkey)) {
 280                 mutex_lock(&idmap->idmap_mutex);
 281                 rkey = request_key_with_auxdata(&key_type_id_resolver_legacy,
 282                                                 desc, "", 0, idmap);
 283                 mutex_unlock(&idmap->idmap_mutex);
 284         }
 285
 286         kfree(desc);
 287         return rkey;
 288 }
 289
 290 static ssize_t nfs_idmap_get_key(const char *name, size_t namelen,
 291                                  const char *type, void *data,
 292                                  size_t data_size, struct idmap *idmap)
 293 {
 294         const struct cred *saved_cred;
 295         struct key *rkey;
 296         struct user_key_payload *payload;
 297         ssize_t ret;
 298
 299         saved_cred = override_creds(id_resolver_cache);
 300         rkey = nfs_idmap_request_key(name, namelen, type, idmap);
 301         revert_creds(saved_cred);
 302
 303         if (IS_ERR(rkey)) {
 304                 ret = PTR_ERR(rkey);
 305                 goto out;
 306         }
 307
 308         rcu_read_lock();
 309         rkey->perm |= KEY_USR_VIEW;
 310
 311         ret = key_validate(rkey);
 312         if (ret < 0)
 313                 goto out_up;
 314
 315         payload = rcu_dereference(rkey->payload.rcudata);
 316         if (IS_ERR_OR_NULL(payload)) {
 317                 ret = PTR_ERR(payload);
 318                 goto out_up;
 319         }
 320
 321         ret = payload->datalen;
 322         if (ret > 0 && ret <= data_size)
 323                 memcpy(data, payload->data, ret);
 324         else
 325                 ret = -EINVAL;
 326
 327 out_up:
 328         rcu_read_unlock();
 329         key_put(rkey);
 330 out:
 331         return ret;
 332 }
 333
 334 /* ID -> Name */
 335 static ssize_t nfs_idmap_lookup_name(__u32 id, const char *type, char *buf,
 336                                      size_t buflen, struct idmap *idmap)
 337 {
 338         char id_str[NFS_UINT_MAXLEN];
 339         int id_len;
 340         ssize_t ret;
 341
 342         id_len = snprintf(id_str, sizeof(id_str), "%u", id);
 343         ret = nfs_idmap_get_key(id_str, id_len, type, buf, buflen, idmap);
 344         if (ret < 0)
 345                 return -EINVAL;
 346         return ret;
 347 }
 348
 349 /* Name -> ID */
 350 static int nfs_idmap_lookup_id(const char *name, size_t namelen, const char *type,
 351                                __u32 *id, struct idmap *idmap)
 352 {
 353         char id_str[NFS_UINT_MAXLEN];
 354         long id_long;
 355         ssize_t data_size;
 356         int ret = 0;
 357
 358         data_size = nfs_idmap_get_key(name, namelen, type, id_str, NFS_UINT_MAXLEN, idmap);
 359         if (data_size <= 0) {
 360                 ret = -EINVAL;
 361         } else {
 362                 ret = kstrtol(id_str, 10, &id_long);
 363                 *id = (__u32)id_long;
 364         }
 365         return ret;
 366 }
 367
 368 /* idmap classic begins here */
 369
 370 enum {
 371         Opt_find_uid, Opt_find_gid, Opt_find_user, Opt_find_group, Opt_find_err
 372 };
 373
 374 static const match_table_t nfs_idmap_tokens = {
 375         { Opt_find_uid, "uid:%s" },
 376         { Opt_find_gid, "gid:%s" },
 377         { Opt_find_user, "user:%s" },
 378         { Opt_find_group, "group:%s" },
 379         { Opt_find_err, NULL }
 380 };
 381
 382 static int nfs_idmap_legacy_upcall(struct key_construction *, const char *, void *);
 383 static ssize_t idmap_pipe_downcall(struct file *, const char __user *,
 384                                    size_t);
 385 static void idmap_release_pipe(struct inode *);
 386 static void idmap_pipe_destroy_msg(struct rpc_pipe_msg *);
 387
 388 static const struct rpc_pipe_ops idmap_upcall_ops = {
 389         .upcall         = rpc_pipe_generic_upcall,
 390         .downcall       = idmap_pipe_downcall,
 391         .release_pipe   = idmap_release_pipe,
 392         .destroy_msg    = idmap_pipe_destroy_msg,
 393 };
 394
 395 static struct key_type key_type_id_resolver_legacy = {
 396         .name           = "id_legacy",
 397         .instantiate    = user_instantiate,
 398         .match          = user_match,
 399         .revoke         = user_revoke,
 400         .destroy        = user_destroy,
 401         .describe       = user_describe,
 402         .read           = user_read,
 403         .request_key    = nfs_idmap_legacy_upcall,
 404 };
 405
 406 static void nfs_idmap_pipe_destroy(struct dentry *dir,
 407                 struct rpc_pipe_dir_object *pdo)
 408 {
 409         struct idmap *idmap = pdo->pdo_data;
 410         struct rpc_pipe *pipe = idmap->idmap_pipe;
 411
 412         if (pipe->dentry) {
 413                 rpc_unlink(pipe->dentry);
 414                 pipe->dentry = NULL;
 415         }
 416 }
 417
 418 static int nfs_idmap_pipe_create(struct dentry *dir,
 419                 struct rpc_pipe_dir_object *pdo)
 420 {
 421         struct idmap *idmap = pdo->pdo_data;
 422         struct rpc_pipe *pipe = idmap->idmap_pipe;
 423         struct dentry *dentry;
 424
 425         dentry = rpc_mkpipe_dentry(dir, "idmap", idmap, pipe);
 426         if (IS_ERR(dentry))
 427                 return PTR_ERR(dentry);
 428         pipe->dentry = dentry;
 429         return 0;
 430 }
 431
 432 static const struct rpc_pipe_dir_object_ops nfs_idmap_pipe_dir_object_ops = {
 433         .create = nfs_idmap_pipe_create,
 434         .destroy = nfs_idmap_pipe_destroy,
 435 };
 436
 437 int
 438 nfs_idmap_new(struct nfs_client *clp)
 439 {
 440         struct idmap *idmap;
 441         struct rpc_pipe *pipe;
 442         int error;
 443
 444         idmap = kzalloc(sizeof(*idmap), GFP_KERNEL);
 445         if (idmap == NULL)
 446                 return -ENOMEM;
 447
 448         rpc_init_pipe_dir_object(&idmap->idmap_pdo,
 449                         &nfs_idmap_pipe_dir_object_ops,
 450                         idmap);
 451
 452         pipe = rpc_mkpipe_data(&idmap_upcall_ops, 0);
 453         if (IS_ERR(pipe)) {
 454                 error = PTR_ERR(pipe);
 455                 goto err;
 456         }
 457         idmap->idmap_pipe = pipe;
 458         mutex_init(&idmap->idmap_mutex);
 459
 460         error = rpc_add_pipe_dir_object(clp->cl_net,
 461                         &clp->cl_rpcclient->cl_pipedir_objects,
 462                         &idmap->idmap_pdo);
 463         if (error)
 464                 goto err_destroy_pipe;
 465
 466         clp->cl_idmap = idmap;
 467         return 0;
 468 err_destroy_pipe:
 469         rpc_destroy_pipe_data(idmap->idmap_pipe);
 470 err:
 471         kfree(idmap);
 472         return error;
 473 }
 474
 475 void
 476 nfs_idmap_delete(struct nfs_client *clp)
 477 {
 478         struct idmap *idmap = clp->cl_idmap;
 479
 480         if (!idmap)
 481                 return;
 482         clp->cl_idmap = NULL;
 483         rpc_remove_pipe_dir_object(clp->cl_net,
 484                         &clp->cl_rpcclient->cl_pipedir_objects,
 485                         &idmap->idmap_pdo);
 486         rpc_destroy_pipe_data(idmap->idmap_pipe);
 487         kfree(idmap);
 488 }
 489
 490 int nfs_idmap_init(void)
 491 {
 492         int ret;
 493         ret = nfs_idmap_init_keyring();
 494         if (ret != 0)
 495                 goto out;
 496 out:
 497         return ret;
 498 }
 499
 500 void nfs_idmap_quit(void)
 501 {
 502         nfs_idmap_quit_keyring();
 503 }
 504
 505 static int nfs_idmap_prepare_message(char *desc, struct idmap *idmap,
 506                                      struct idmap_msg *im,
 507                                      struct rpc_pipe_msg *msg)
 508 {
 509         substring_t substr;
 510         int token, ret;
 511
 512         im->im_type = IDMAP_TYPE_GROUP;
 513         token = match_token(desc, nfs_idmap_tokens, &substr);
 514
 515         switch (token) {
 516         case Opt_find_uid:
 517                 im->im_type = IDMAP_TYPE_USER;
 518         case Opt_find_gid:
 519                 im->im_conv = IDMAP_CONV_NAMETOID;
 520                 ret = match_strlcpy(im->im_name, &substr, IDMAP_NAMESZ);
 521                 break;
 522
 523         case Opt_find_user:
 524                 im->im_type = IDMAP_TYPE_USER;
 525         case Opt_find_group:
 526                 im->im_conv = IDMAP_CONV_IDTONAME;
 527                 ret = match_int(&substr, &im->im_id);
 528                 break;
 529
 530         default:
 531                 ret = -EINVAL;
 532                 goto out;
 533         }
 534
 535         msg->data = im;
 536         msg->len  = sizeof(struct idmap_msg);
 537
 538 out:
 539         return ret;
 540 }
 541
 542 static bool
 543 nfs_idmap_prepare_pipe_upcall(struct idmap *idmap,
 544                 struct idmap_legacy_upcalldata *data)
 545 {
 546         if (idmap->idmap_upcall_data != NULL) {
 547                 WARN_ON_ONCE(1);
 548                 return false;
 549         }
 550         idmap->idmap_upcall_data = data;
 551         return true;
 552 }
 553
 554 static void
 555 nfs_idmap_complete_pipe_upcall_locked(struct idmap *idmap, int ret)
 556 {
 557         struct key_construction *cons = idmap->idmap_upcall_data->key_cons;
 558
 559         kfree(idmap->idmap_upcall_data);
 560         idmap->idmap_upcall_data = NULL;
 561         complete_request_key(cons, ret);
 562 }
 563
 564 static void
 565 nfs_idmap_abort_pipe_upcall(struct idmap *idmap, int ret)
 566 {
 567         if (idmap->idmap_upcall_data != NULL)
 568                 nfs_idmap_complete_pipe_upcall_locked(idmap, ret);
 569 }
 570
 571 static int nfs_idmap_legacy_upcall(struct key_construction *cons,
 572                                    const char *op,
 573                                    void *aux)
 574 {
 575         struct idmap_legacy_upcalldata *data;
 576         struct rpc_pipe_msg *msg;
 577         struct idmap_msg *im;
 578         struct idmap *idmap = (struct idmap *)aux;
 579         struct key *key = cons->key;
 580         int ret = -ENOMEM;
 581
 582         /* msg and im are freed in idmap_pipe_destroy_msg */
 583         data = kzalloc(sizeof(*data), GFP_KERNEL);
 584         if (!data)
 585                 goto out1;
 586
 587         msg = &data->pipe_msg;
 588         im = &data->idmap_msg;
 589         data->idmap = idmap;
 590         data->key_cons = cons;
 591
 592         ret = nfs_idmap_prepare_message(key->description, idmap, im, msg);
 593         if (ret < 0)
 594                 goto out2;
 595
 596         ret = -EAGAIN;
 597         if (!nfs_idmap_prepare_pipe_upcall(idmap, data))
 598                 goto out2;
 599
 600         ret = rpc_queue_upcall(idmap->idmap_pipe, msg);
 601         if (ret < 0)
 602                 nfs_idmap_abort_pipe_upcall(idmap, ret);
 603
 604         return ret;
 605 out2:
 606         kfree(data);
 607 out1:
 608         complete_request_key(cons, ret);
 609         return ret;
 610 }
 611
 612 static int nfs_idmap_instantiate(struct key *key, struct key *authkey, char *data, size_t datalen)
 613 {
 614         return key_instantiate_and_link(key, data, datalen,
 615                                         id_resolver_cache->thread_keyring,
 616                                         authkey);
 617 }
 618
 619 static int nfs_idmap_read_and_verify_message(struct idmap_msg *im,
 620                 struct idmap_msg *upcall,
 621                 struct key *key, struct key *authkey)
 622 {
 623         char id_str[NFS_UINT_MAXLEN];
 624         size_t len;
 625         int ret = -ENOKEY;
 626
 627         /* ret = -ENOKEY */
 628         if (upcall->im_type != im->im_type || upcall->im_conv != im->im_conv)
 629                 goto out;
 630         switch (im->im_conv) {
 631         case IDMAP_CONV_NAMETOID:
 632                 if (strcmp(upcall->im_name, im->im_name) != 0)
 633                         break;
 634                 /* Note: here we store the NUL terminator too */
 635                 len = sprintf(id_str, "%d", im->im_id) + 1;
 636                 ret = nfs_idmap_instantiate(key, authkey, id_str, len);
 637                 break;
 638         case IDMAP_CONV_IDTONAME:
 639                 if (upcall->im_id != im->im_id)
 640                         break;
 641                 len = strlen(im->im_name);
 642                 ret = nfs_idmap_instantiate(key, authkey, im->im_name, len);
 643                 break;
 644         default:
 645                 ret = -EINVAL;
 646         }
 647 out:
 648         return ret;
 649 }
 650
 651 static ssize_t
 652 idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
 653 {
 654         struct rpc_inode *rpci = RPC_I(file_inode(filp));
 655         struct idmap *idmap = (struct idmap *)rpci->private;
 656         struct key_construction *cons;
 657         struct idmap_msg im;
 658         size_t namelen_in;
 659         int ret = -ENOKEY;
 660
 661         /* If instantiation is successful, anyone waiting for key construction
 662          * will have been woken up and someone else may now have used
 663          * idmap_key_cons - so after this point we may no longer touch it.
 664          */
 665         if (idmap->idmap_upcall_data == NULL)
 666                 goto out_noupcall;
 667
 668         cons = idmap->idmap_upcall_data->key_cons;
 669
 670         if (mlen != sizeof(im)) {
 671                 ret = -ENOSPC;
 672                 goto out;
 673         }
 674
 675         if (copy_from_user(&im, src, mlen) != 0) {
 676                 ret = -EFAULT;
 677                 goto out;
 678         }
 679
 680         if (!(im.im_status & IDMAP_STATUS_SUCCESS)) {
 681                 ret = -ENOKEY;
 682                 goto out;
 683         }
 684
 685         namelen_in = strnlen(im.im_name, IDMAP_NAMESZ);
 686         if (namelen_in == 0 || namelen_in == IDMAP_NAMESZ) {
 687                 ret = -EINVAL;
 688                 goto out;
 689 }
 690
 691         ret = nfs_idmap_read_and_verify_message(&im,
 692                         &idmap->idmap_upcall_data->idmap_msg,
 693                         cons->key, cons->authkey);
 694         if (ret >= 0) {
 695                 key_set_timeout(cons->key, nfs_idmap_cache_timeout);
 696                 ret = mlen;
 697         }
 698
 699 out:
 700         nfs_idmap_complete_pipe_upcall_locked(idmap, ret);
 701 out_noupcall:
 702         return ret;
 703 }
 704
 705 static void
 706 idmap_pipe_destroy_msg(struct rpc_pipe_msg *msg)
 707 {
 708         struct idmap_legacy_upcalldata *data = container_of(msg,
 709                         struct idmap_legacy_upcalldata,
 710                         pipe_msg);
 711         struct idmap *idmap = data->idmap;
 712
 713         if (msg->errno)
 714                 nfs_idmap_abort_pipe_upcall(idmap, msg->errno);
 715 }
 716
 717 static void
 718 idmap_release_pipe(struct inode *inode)
 719 {
 720         struct rpc_inode *rpci = RPC_I(inode);
 721         struct idmap *idmap = (struct idmap *)rpci->private;
 722
 723         nfs_idmap_abort_pipe_upcall(idmap, -EPIPE);
 724 }
 725
 726 int nfs_map_name_to_uid(const struct nfs_server *server, const char *name, size_t namelen, kuid_t *uid)
 727 {
 728         struct idmap *idmap = server->nfs_client->cl_idmap;
 729         __u32 id = -1;
 730         int ret = 0;
 731
 732         if (!nfs_map_string_to_numeric(name, namelen, &id))
 733                 ret = nfs_idmap_lookup_id(name, namelen, "uid", &id, idmap);
 734         if (ret == 0) {
 735                 *uid = make_kuid(&init_user_ns, id);
 736                 if (!uid_valid(*uid))
 737                         ret = -ERANGE;
 738         }
 739         trace_nfs4_map_name_to_uid(name, namelen, id, ret);
 740         return ret;
 741 }
 742
 743 int nfs_map_group_to_gid(const struct nfs_server *server, const char *name, size_t namelen, kgid_t *gid)
 744 {
 745         struct idmap *idmap = server->nfs_client->cl_idmap;
 746         __u32 id = -1;
 747         int ret = 0;
 748
 749         if (!nfs_map_string_to_numeric(name, namelen, &id))
 750                 ret = nfs_idmap_lookup_id(name, namelen, "gid", &id, idmap);
 751         if (ret == 0) {
 752                 *gid = make_kgid(&init_user_ns, id);
 753                 if (!gid_valid(*gid))
 754                         ret = -ERANGE;
 755         }
 756         trace_nfs4_map_group_to_gid(name, namelen, id, ret);
 757         return ret;
 758 }
 759
 760 int nfs_map_uid_to_name(const struct nfs_server *server, kuid_t uid, char *buf, size_t buflen)
 761 {
 762         struct idmap *idmap = server->nfs_client->cl_idmap;
 763         int ret = -EINVAL;
 764         __u32 id;
 765
 766         id = from_kuid(&init_user_ns, uid);
 767         if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
 768                 ret = nfs_idmap_lookup_name(id, "user", buf, buflen, idmap);
 769         if (ret < 0)
 770                 ret = nfs_map_numeric_to_string(id, buf, buflen);
 771         trace_nfs4_map_uid_to_name(buf, ret, id, ret);
 772         return ret;
 773 }
 774 int nfs_map_gid_to_group(const struct nfs_server *server, kgid_t gid, char *buf, size_t buflen)
 775 {
 776         struct idmap *idmap = server->nfs_client->cl_idmap;
 777         int ret = -EINVAL;
 778         __u32 id;
 779
 780         id = from_kgid(&init_user_ns, gid);
 781         if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
 782                 ret = nfs_idmap_lookup_name(id, "group", buf, buflen, idmap);
 783         if (ret < 0)
 784                 ret = nfs_map_numeric_to_string(id, buf, buflen);
 785         trace_nfs4_map_gid_to_group(buf, ret, id, ret);
 786         return ret;
 787 }