drivers/staging/lustre/lustre/obdclass/capa.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) 2005, 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/capa.c
  37  *
  38  * Lustre Capability Hash Management
  39  *
  40  * Author: Lai Siyao<lsy@clusterfs.com>
  41  */
  42
  43 #define DEBUG_SUBSYSTEM S_SEC
  44
  45 #include <linux/fs.h>
  46 #include <asm/unistd.h>
  47 #include <linux/slab.h>
  48 #include <linux/module.h>
  49 #include <linux/crypto.h>
  50
  51 #include <obd_class.h>
  52 #include <lustre_debug.h>
  53 #include <lustre/lustre_idl.h>
  54
  55 #include <linux/list.h>
  56 #include <lustre_capa.h>
  57
  58 #define NR_CAPAHASH 32
  59 #define CAPA_HASH_SIZE 3000           /* for MDS & OSS */
  60
  61 struct kmem_cache *capa_cachep = NULL;
  62
  63 /* lock for capa hash/capa_list/fo_capa_keys */
  64 DEFINE_SPINLOCK(capa_lock);
  65
  66 struct list_head capa_list[CAPA_SITE_MAX];
  67
  68 static struct capa_hmac_alg capa_hmac_algs[] = {
  69         DEF_CAPA_HMAC_ALG("sha1", SHA1, 20, 20),
  70 };
  71 /* capa count */
  72 int capa_count[CAPA_SITE_MAX] = { 0, };
  73
  74 EXPORT_SYMBOL(capa_cachep);
  75 EXPORT_SYMBOL(capa_list);
  76 EXPORT_SYMBOL(capa_lock);
  77 EXPORT_SYMBOL(capa_count);
  78
  79 static inline
  80 unsigned int ll_crypto_tfm_alg_min_keysize(struct crypto_blkcipher *tfm)
  81 {
  82         return crypto_blkcipher_tfm(tfm)->__crt_alg->cra_blkcipher.min_keysize;
  83 }
  84
  85 struct hlist_head *init_capa_hash(void)
  86 {
  87         struct hlist_head *hash;
  88         int nr_hash, i;
  89
  90         OBD_ALLOC(hash, PAGE_CACHE_SIZE);
  91         if (!hash)
  92                 return NULL;
  93
  94         nr_hash = PAGE_CACHE_SIZE / sizeof(struct hlist_head);
  95         LASSERT(nr_hash > NR_CAPAHASH);
  96
  97         for (i = 0; i < NR_CAPAHASH; i++)
  98                 INIT_HLIST_HEAD(hash + i);
  99         return hash;
 100 }
 101 EXPORT_SYMBOL(init_capa_hash);
 102
 103 static inline int capa_on_server(struct obd_capa *ocapa)
 104 {
 105         return ocapa->c_site == CAPA_SITE_SERVER;
 106 }
 107
 108 static inline void capa_delete(struct obd_capa *ocapa)
 109 {
 110         LASSERT(capa_on_server(ocapa));
 111         hlist_del_init(&ocapa->u.tgt.c_hash);
 112         list_del_init(&ocapa->c_list);
 113         capa_count[ocapa->c_site]--;
 114         /* release the ref when alloc */
 115         capa_put(ocapa);
 116 }
 117
 118 void cleanup_capa_hash(struct hlist_head *hash)
 119 {
 120         int i;
 121         struct hlist_node *next;
 122         struct obd_capa *oc;
 123
 124         spin_lock(&capa_lock);
 125         for (i = 0; i < NR_CAPAHASH; i++) {
 126                 hlist_for_each_entry_safe(oc, next, hash + i,
 127                                               u.tgt.c_hash)
 128                         capa_delete(oc);
 129         }
 130         spin_unlock(&capa_lock);
 131
 132         OBD_FREE(hash, PAGE_CACHE_SIZE);
 133 }
 134 EXPORT_SYMBOL(cleanup_capa_hash);
 135
 136 static inline int capa_hashfn(struct lu_fid *fid)
 137 {
 138         return (fid_oid(fid) ^ fid_ver(fid)) *
 139                (unsigned long)(fid_seq(fid) + 1) % NR_CAPAHASH;
 140 }
 141
 142 /* capa renewal time check is earlier than that on client, which is to prevent
 143  * client renew right after obtaining it. */
 144 static inline int capa_is_to_expire(struct obd_capa *oc)
 145 {
 146         return cfs_time_before(cfs_time_sub(oc->c_expiry,
 147                                    cfs_time_seconds(oc->c_capa.lc_timeout)*2/3),
 148                                cfs_time_current());
 149 }
 150
 151 static struct obd_capa *find_capa(struct lustre_capa *capa,
 152                                   struct hlist_head *head, int alive)
 153 {
 154         struct obd_capa *ocapa;
 155         int len = alive ? offsetof(struct lustre_capa, lc_keyid):sizeof(*capa);
 156
 157         hlist_for_each_entry(ocapa, head, u.tgt.c_hash) {
 158                 if (memcmp(&ocapa->c_capa, capa, len))
 159                         continue;
 160                 /* don't return one that will expire soon in this case */
 161                 if (alive && capa_is_to_expire(ocapa))
 162                         continue;
 163
 164                 LASSERT(capa_on_server(ocapa));
 165
 166                 DEBUG_CAPA(D_SEC, &ocapa->c_capa, "found");
 167                 return ocapa;
 168         }
 169
 170         return NULL;
 171 }
 172
 173 #define LRU_CAPA_DELETE_COUNT 12
 174 static inline void capa_delete_lru(struct list_head *head)
 175 {
 176         struct obd_capa *ocapa;
 177         struct list_head *node = head->next;
 178         int count = 0;
 179
 180         /* free LRU_CAPA_DELETE_COUNT unused capa from head */
 181         while (count++ < LRU_CAPA_DELETE_COUNT) {
 182                 ocapa = list_entry(node, struct obd_capa, c_list);
 183                 node = node->next;
 184                 if (atomic_read(&ocapa->c_refc))
 185                         continue;
 186
 187                 DEBUG_CAPA(D_SEC, &ocapa->c_capa, "free lru");
 188                 capa_delete(ocapa);
 189         }
 190 }
 191
 192 /* add or update */
 193 struct obd_capa *capa_add(struct hlist_head *hash, struct lustre_capa *capa)
 194 {
 195         struct hlist_head *head = hash + capa_hashfn(&capa->lc_fid);
 196         struct obd_capa *ocapa, *old = NULL;
 197         struct list_head *list = &capa_list[CAPA_SITE_SERVER];
 198
 199         ocapa = alloc_capa(CAPA_SITE_SERVER);
 200         if (IS_ERR(ocapa))
 201                 return NULL;
 202
 203         spin_lock(&capa_lock);
 204         old = find_capa(capa, head, 0);
 205         if (!old) {
 206                 ocapa->c_capa = *capa;
 207                 set_capa_expiry(ocapa);
 208                 hlist_add_head(&ocapa->u.tgt.c_hash, head);
 209                 list_add_tail(&ocapa->c_list, list);
 210                 capa_get(ocapa);
 211                 capa_count[CAPA_SITE_SERVER]++;
 212                 if (capa_count[CAPA_SITE_SERVER] > CAPA_HASH_SIZE)
 213                         capa_delete_lru(list);
 214                 spin_unlock(&capa_lock);
 215                 return ocapa;
 216         } else {
 217                 capa_get(old);
 218                 spin_unlock(&capa_lock);
 219                 capa_put(ocapa);
 220                 return old;
 221         }
 222 }
 223 EXPORT_SYMBOL(capa_add);
 224
 225 struct obd_capa *capa_lookup(struct hlist_head *hash, struct lustre_capa *capa,
 226                              int alive)
 227 {
 228         struct obd_capa *ocapa;
 229
 230         spin_lock(&capa_lock);
 231         ocapa = find_capa(capa, hash + capa_hashfn(&capa->lc_fid), alive);
 232         if (ocapa) {
 233                 list_move_tail(&ocapa->c_list,
 234                                    &capa_list[CAPA_SITE_SERVER]);
 235                 capa_get(ocapa);
 236         }
 237         spin_unlock(&capa_lock);
 238
 239         return ocapa;
 240 }
 241 EXPORT_SYMBOL(capa_lookup);
 242
 243 static inline int ll_crypto_hmac(struct crypto_hash *tfm,
 244                                  u8 *key, unsigned int *keylen,
 245                                  struct scatterlist *sg,
 246                                  unsigned int size, u8 *result)
 247 {
 248         struct hash_desc desc;
 249         int           rv;
 250         desc.tfm   = tfm;
 251         desc.flags = 0;
 252         rv = crypto_hash_setkey(desc.tfm, key, *keylen);
 253         if (rv) {
 254                 CERROR("failed to hash setkey: %d\n", rv);
 255                 return rv;
 256         }
 257         return crypto_hash_digest(&desc, sg, size, result);
 258 }
 259
 260 int capa_hmac(__u8 *hmac, struct lustre_capa *capa, __u8 *key)
 261 {
 262         struct crypto_hash *tfm;
 263         struct capa_hmac_alg  *alg;
 264         int keylen;
 265         struct scatterlist sl;
 266
 267         if (capa_alg(capa) != CAPA_HMAC_ALG_SHA1) {
 268                 CERROR("unknown capability hmac algorithm!\n");
 269                 return -EFAULT;
 270         }
 271
 272         alg = &capa_hmac_algs[capa_alg(capa)];
 273
 274         tfm = crypto_alloc_hash(alg->ha_name, 0, 0);
 275         if (!tfm) {
 276                 CERROR("crypto_alloc_tfm failed, check whether your kernel"
 277                        "has crypto support!\n");
 278                 return -ENOMEM;
 279         }
 280         keylen = alg->ha_keylen;
 281
 282         sg_set_page(&sl, virt_to_page(capa),
 283                     offsetof(struct lustre_capa, lc_hmac),
 284                     (unsigned long)(capa) % PAGE_CACHE_SIZE);
 285
 286         ll_crypto_hmac(tfm, key, &keylen, &sl, sl.length, hmac);
 287         crypto_free_hash(tfm);
 288
 289         return 0;
 290 }
 291 EXPORT_SYMBOL(capa_hmac);
 292
 293 int capa_encrypt_id(__u32 *d, __u32 *s, __u8 *key, int keylen)
 294 {
 295         struct crypto_blkcipher *tfm;
 296         struct scatterlist sd;
 297         struct scatterlist ss;
 298         struct blkcipher_desc desc;
 299         unsigned int min;
 300         int rc;
 301         char alg[CRYPTO_MAX_ALG_NAME+1] = "aes";
 302
 303         /* passing "aes" in a variable instead of a constant string keeps gcc
 304          * 4.3.2 happy */
 305         tfm = crypto_alloc_blkcipher(alg, 0, 0 );
 306         if (IS_ERR(tfm)) {
 307                 CERROR("failed to load transform for aes\n");
 308                 return PTR_ERR(tfm);
 309         }
 310
 311         min = ll_crypto_tfm_alg_min_keysize(tfm);
 312         if (keylen < min) {
 313                 CERROR("keylen at least %d bits for aes\n", min * 8);
 314                 GOTO(out, rc = -EINVAL);
 315         }
 316
 317         rc = crypto_blkcipher_setkey(tfm, key, min);
 318         if (rc) {
 319                 CERROR("failed to setting key for aes\n");
 320                 GOTO(out, rc);
 321         }
 322
 323         sg_set_page(&sd, virt_to_page(d), 16,
 324                     (unsigned long)(d) % PAGE_CACHE_SIZE);
 325
 326         sg_set_page(&ss, virt_to_page(s), 16,
 327                     (unsigned long)(s) % PAGE_CACHE_SIZE);
 328         desc.tfm   = tfm;
 329         desc.info  = NULL;
 330         desc.flags = 0;
 331         rc = crypto_blkcipher_encrypt(&desc, &sd, &ss, 16);
 332         if (rc) {
 333                 CERROR("failed to encrypt for aes\n");
 334                 GOTO(out, rc);
 335         }
 336
 337 out:
 338         crypto_free_blkcipher(tfm);
 339         return rc;
 340 }
 341 EXPORT_SYMBOL(capa_encrypt_id);
 342
 343 int capa_decrypt_id(__u32 *d, __u32 *s, __u8 *key, int keylen)
 344 {
 345         struct crypto_blkcipher *tfm;
 346         struct scatterlist sd;
 347         struct scatterlist ss;
 348         struct blkcipher_desc desc;
 349         unsigned int min;
 350         int rc;
 351         char alg[CRYPTO_MAX_ALG_NAME+1] = "aes";
 352
 353         /* passing "aes" in a variable instead of a constant string keeps gcc
 354          * 4.3.2 happy */
 355         tfm = crypto_alloc_blkcipher(alg, 0, 0 );
 356         if (IS_ERR(tfm)) {
 357                 CERROR("failed to load transform for aes\n");
 358                 return PTR_ERR(tfm);
 359         }
 360
 361         min = ll_crypto_tfm_alg_min_keysize(tfm);
 362         if (keylen < min) {
 363                 CERROR("keylen at least %d bits for aes\n", min * 8);
 364                 GOTO(out, rc = -EINVAL);
 365         }
 366
 367         rc = crypto_blkcipher_setkey(tfm, key, min);
 368         if (rc) {
 369                 CERROR("failed to setting key for aes\n");
 370                 GOTO(out, rc);
 371         }
 372
 373         sg_set_page(&sd, virt_to_page(d), 16,
 374                     (unsigned long)(d) % PAGE_CACHE_SIZE);
 375
 376         sg_set_page(&ss, virt_to_page(s), 16,
 377                     (unsigned long)(s) % PAGE_CACHE_SIZE);
 378
 379         desc.tfm   = tfm;
 380         desc.info  = NULL;
 381         desc.flags = 0;
 382         rc = crypto_blkcipher_decrypt(&desc, &sd, &ss, 16);
 383         if (rc) {
 384                 CERROR("failed to decrypt for aes\n");
 385                 GOTO(out, rc);
 386         }
 387
 388 out:
 389         crypto_free_blkcipher(tfm);
 390         return rc;
 391 }
 392 EXPORT_SYMBOL(capa_decrypt_id);
 393
 394 void capa_cpy(void *capa, struct obd_capa *ocapa)
 395 {
 396         spin_lock(&ocapa->c_lock);
 397         *(struct lustre_capa *)capa = ocapa->c_capa;
 398         spin_unlock(&ocapa->c_lock);
 399 }
 400 EXPORT_SYMBOL(capa_cpy);
 401
 402 void _debug_capa(struct lustre_capa *c,
 403                  struct libcfs_debug_msg_data *msgdata,
 404                  const char *fmt, ... )
 405 {
 406         va_list args;
 407         va_start(args, fmt);
 408         libcfs_debug_vmsg2(msgdata, fmt, args,
 409                            " capability@%p fid "DFID" opc "LPX64" uid "LPU64
 410                            " gid "LPU64" flags %u alg %d keyid %u timeout %u "
 411                            "expiry %u\n", c, PFID(capa_fid(c)), capa_opc(c),
 412                            capa_uid(c), capa_gid(c), capa_flags(c),
 413                            capa_alg(c), capa_keyid(c), capa_timeout(c),
 414                            capa_expiry(c));
 415         va_end(args);
 416 }
 417 EXPORT_SYMBOL(_debug_capa);