lustre/obdfilter/filter_capa.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * GPL HEADER START
   5  *
   6  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 only,
  10  * as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License version 2 for more details (a copy is included
  16  * in the LICENSE file that accompanied this code).
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * version 2 along with this program; If not, see [sun.com URL with a
  20  * copy of GPLv2].
  21  *
  22  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  23  * CA 95054 USA or visit www.sun.com if you need additional information or
  24  * have any questions.
  25  *
  26  * GPL HEADER END
  27  */
  28 /*
  29  * Copyright  2008 Sun Microsystems, Inc. All rights reserved
  30  * Use is subject to license terms.
  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/obdfilter/filter_capa.c
  37  *
  38  * Author: Lai Siyao <lsy@clusterfs.com>
  39  */
  40
  41 #define DEBUG_SUBSYSTEM S_FILTER
  42
  43 #include <linux/fs.h>
  44 #include <linux/version.h>
  45 #include <asm/uaccess.h>
  46 #include <linux/file.h>
  47 #include <linux/kmod.h>
  48
  49 #include <lustre_fsfilt.h>
  50 #include <lustre_capa.h>
  51
  52 #include "filter_internal.h"
  53
  54 static inline __u32 filter_ck_keyid(struct filter_capa_key *key)
  55 {
  56         return key->k_key.lk_keyid;
  57 }
  58
  59 int filter_update_capa_key(struct obd_device *obd, struct lustre_capa_key *new)
  60 {
  61         struct filter_obd *filter = &obd->u.filter;
  62         struct filter_capa_key *k, *keys[2] = { NULL, NULL };
  63         int i;
  64
  65         spin_lock(&capa_lock);
  66         list_for_each_entry(k, &filter->fo_capa_keys, k_list) {
  67                 if (k->k_key.lk_mdsid != new->lk_mdsid)
  68                         continue;
  69
  70                 if (keys[0]) {
  71                         keys[1] = k;
  72                         if (filter_ck_keyid(keys[1]) > filter_ck_keyid(keys[0]))
  73                                 keys[1] = keys[0], keys[0] = k;
  74                 } else {
  75                         keys[0] = k;
  76                 }
  77         }
  78         spin_unlock(&capa_lock);
  79
  80         for (i = 0; i < 2; i++) {
  81                 if (!keys[i])
  82                         continue;
  83                 if (filter_ck_keyid(keys[i]) != new->lk_keyid)
  84                         continue;
  85                 /* maybe because of recovery or other reasons, MDS sent the
  86                  * the old capability key again.
  87                  */
  88                 spin_lock(&capa_lock);
  89                 keys[i]->k_key = *new;
  90                 spin_unlock(&capa_lock);
  91
  92                 RETURN(0);
  93         }
  94
  95         if (keys[1]) {
  96                 /* if OSS already have two keys, update the old one */
  97                 k = keys[1];
  98         } else {
  99                 OBD_ALLOC_PTR(k);
 100                 if (!k)
 101                         RETURN(-ENOMEM);
 102                 CFS_INIT_LIST_HEAD(&k->k_list);
 103         }
 104
 105         spin_lock(&capa_lock);
 106         k->k_key = *new;
 107         if (list_empty(&k->k_list))
 108                 list_add(&k->k_list, &filter->fo_capa_keys);
 109         spin_unlock(&capa_lock);
 110
 111         DEBUG_CAPA_KEY(D_SEC, new, "new");
 112         RETURN(0);
 113 }
 114
 115 int filter_auth_capa(struct obd_export *exp, struct lu_fid *fid, __u64 mdsid,
 116                      struct lustre_capa *capa, __u64 opc)
 117 {
 118         struct obd_device *obd = exp->exp_obd;
 119         struct filter_obd *filter = &obd->u.filter;
 120         struct filter_capa_key *k;
 121         struct lustre_capa_key key;
 122         struct obd_capa *oc;
 123         __u8 *hmac;
 124         int keys_ready = 0, key_found = 0, rc = 0;
 125         ENTRY;
 126
 127         /* capability is disabled */
 128         if (!filter->fo_fl_oss_capa)
 129                 RETURN(0);
 130
 131         if (capa == NULL) {
 132                 if (fid)
 133                         CERROR("mdsno/fid/opc "LPU64"/"DFID"/"LPX64
 134                                ": no capability has been passed\n",
 135                                mdsid, PFID(fid), opc);
 136                 else
 137                         CERROR("mdsno/opc "LPU64"/"LPX64
 138                                ": no capability has been passed\n",
 139                                mdsid, opc);
 140                 RETURN(-EACCES);
 141         }
 142
 143         if (opc == CAPA_OPC_OSS_READ) {
 144                 if (!(capa->lc_opc & CAPA_OPC_OSS_RW))
 145                         rc = -EACCES;
 146         } else if (!capa_opc_supported(capa, opc)) {
 147                 rc = -EACCES;
 148         }
 149         if (rc) {
 150                 DEBUG_CAPA(D_ERROR, capa, "opc "LPX64" not supported by", opc);
 151                 RETURN(rc);
 152         }
 153
 154         oc = capa_lookup(filter->fo_capa_hash, capa, 0);
 155         if (oc) {
 156                 spin_lock(&oc->c_lock);
 157                 if (capa_is_expired(oc)) {
 158                         DEBUG_CAPA(D_ERROR, capa, "expired");
 159                         rc = -ESTALE;
 160                 }
 161                 spin_unlock(&oc->c_lock);
 162
 163                 capa_put(oc);
 164                 RETURN(rc);
 165         }
 166
 167         spin_lock(&capa_lock);
 168         list_for_each_entry(k, &filter->fo_capa_keys, k_list)
 169                 if (k->k_key.lk_mdsid == mdsid) {
 170                         keys_ready = 1;
 171                         if (k->k_key.lk_keyid == capa_keyid(capa)) {
 172                                 key = k->k_key;
 173                                 key_found = 1;
 174                                 break;
 175                         }
 176                 }
 177         spin_unlock(&capa_lock);
 178
 179         if (!keys_ready) {
 180                 CDEBUG(D_SEC, "MDS hasn't propagated capability keys yet, "
 181                        "ignore check!\n");
 182                 RETURN(0);
 183         }
 184
 185        if (!key_found) {
 186                 DEBUG_CAPA(D_ERROR, capa, "no matched capability key for");
 187                 RETURN(-ESTALE);
 188         }
 189
 190         OBD_ALLOC(hmac, CAPA_HMAC_MAX_LEN);
 191         if (hmac == NULL)
 192                 RETURN(-ENOMEM);
 193
 194         rc = capa_hmac(hmac, capa, key.lk_key);
 195         if (rc) {
 196                 DEBUG_CAPA(D_ERROR, capa, "HMAC failed: rc %d", rc);
 197                 OBD_FREE(hmac, CAPA_HMAC_MAX_LEN);
 198                 RETURN(rc);
 199         }
 200
 201         rc = memcmp(hmac, capa->lc_hmac, CAPA_HMAC_MAX_LEN);
 202         OBD_FREE(hmac, CAPA_HMAC_MAX_LEN);
 203         if (rc) {
 204                 DEBUG_CAPA_KEY(D_ERROR, &key, "calculate HMAC with ");
 205                 DEBUG_CAPA(D_ERROR, capa, "HMAC mismatch");
 206                 RETURN(-EACCES);
 207         }
 208
 209         /* store in capa hash */
 210         oc = capa_add(filter->fo_capa_hash, capa);
 211         capa_put(oc);
 212         RETURN(0);
 213 }
 214
 215 void filter_free_capa_keys(struct filter_obd *filter)
 216 {
 217         struct filter_capa_key *key, *n;
 218
 219         spin_lock(&capa_lock);
 220         list_for_each_entry_safe(key, n, &filter->fo_capa_keys, k_list) {
 221                 list_del_init(&key->k_list);
 222                 OBD_FREE(key, sizeof(*key));
 223         }
 224         spin_unlock(&capa_lock);
 225 }