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