NeilBrown | a55370a | 2005-06-23 22:03:52 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/fs/nfsd/nfs4recover.c |
| 3 | * |
| 4 | * Copyright (c) 2004 The Regents of the University of Michigan. |
| 5 | * All rights reserved. |
| 6 | * |
| 7 | * Andy Adamson <andros@citi.umich.edu> |
| 8 | * |
| 9 | * Redistribution and use in source and binary forms, with or without |
| 10 | * modification, are permitted provided that the following conditions |
| 11 | * are met: |
| 12 | * |
| 13 | * 1. Redistributions of source code must retain the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer. |
| 15 | * 2. Redistributions in binary form must reproduce the above copyright |
| 16 | * notice, this list of conditions and the following disclaimer in the |
| 17 | * documentation and/or other materials provided with the distribution. |
| 18 | * 3. Neither the name of the University nor the names of its |
| 19 | * contributors may be used to endorse or promote products derived |
| 20 | * from this software without specific prior written permission. |
| 21 | * |
| 22 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED |
| 23 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| 24 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| 25 | * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 26 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 27 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 28 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR |
| 29 | * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
| 30 | * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
| 31 | * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
| 32 | * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 33 | * |
| 34 | */ |
| 35 | |
| 36 | |
| 37 | #include <linux/sunrpc/svc.h> |
| 38 | #include <linux/nfsd/nfsd.h> |
| 39 | #include <linux/nfs4.h> |
| 40 | #include <linux/nfsd/state.h> |
| 41 | #include <linux/nfsd/xdr4.h> |
NeilBrown | 190e4fb | 2005-06-23 22:04:25 -0700 | [diff] [blame^] | 42 | #include <linux/param.h> |
| 43 | #include <linux/file.h> |
| 44 | #include <linux/namei.h> |
NeilBrown | a55370a | 2005-06-23 22:03:52 -0700 | [diff] [blame] | 45 | #include <asm/uaccess.h> |
| 46 | #include <asm/scatterlist.h> |
| 47 | #include <linux/crypto.h> |
| 48 | |
| 49 | |
| 50 | #define NFSDDBG_FACILITY NFSDDBG_PROC |
| 51 | |
NeilBrown | 190e4fb | 2005-06-23 22:04:25 -0700 | [diff] [blame^] | 52 | /* Globals */ |
| 53 | char recovery_dirname[PATH_MAX] = "/var/lib/nfs/v4recovery"; |
| 54 | static struct nameidata rec_dir; |
| 55 | static int rec_dir_init = 0; |
| 56 | |
| 57 | static void |
| 58 | nfs4_save_user(uid_t *saveuid, gid_t *savegid) |
| 59 | { |
| 60 | *saveuid = current->fsuid; |
| 61 | *savegid = current->fsgid; |
| 62 | current->fsuid = 0; |
| 63 | current->fsgid = 0; |
| 64 | } |
| 65 | |
| 66 | static void |
| 67 | nfs4_reset_user(uid_t saveuid, gid_t savegid) |
| 68 | { |
| 69 | current->fsuid = saveuid; |
| 70 | current->fsgid = savegid; |
| 71 | } |
| 72 | |
NeilBrown | a55370a | 2005-06-23 22:03:52 -0700 | [diff] [blame] | 73 | static void |
| 74 | md5_to_hex(char *out, char *md5) |
| 75 | { |
| 76 | int i; |
| 77 | |
| 78 | for (i=0; i<16; i++) { |
| 79 | unsigned char c = md5[i]; |
| 80 | |
| 81 | *out++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1); |
| 82 | *out++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1); |
| 83 | } |
| 84 | *out = '\0'; |
| 85 | } |
| 86 | |
| 87 | int |
| 88 | nfs4_make_rec_clidname(char *dname, struct xdr_netobj *clname) |
| 89 | { |
| 90 | struct xdr_netobj cksum; |
| 91 | struct crypto_tfm *tfm; |
| 92 | struct scatterlist sg[1]; |
| 93 | int status = nfserr_resource; |
| 94 | |
| 95 | dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n", |
| 96 | clname->len, clname->data); |
| 97 | tfm = crypto_alloc_tfm("md5", 0); |
| 98 | if (tfm == NULL) |
| 99 | goto out; |
| 100 | cksum.len = crypto_tfm_alg_digestsize(tfm); |
| 101 | cksum.data = kmalloc(cksum.len, GFP_KERNEL); |
| 102 | if (cksum.data == NULL) |
| 103 | goto out; |
| 104 | crypto_digest_init(tfm); |
| 105 | |
| 106 | sg[0].page = virt_to_page(clname->data); |
| 107 | sg[0].offset = offset_in_page(clname->data); |
| 108 | sg[0].length = clname->len; |
| 109 | |
| 110 | crypto_digest_update(tfm, sg, 1); |
| 111 | crypto_digest_final(tfm, cksum.data); |
| 112 | |
| 113 | md5_to_hex(dname, cksum.data); |
| 114 | |
| 115 | kfree(cksum.data); |
| 116 | status = nfs_ok; |
| 117 | out: |
| 118 | if (tfm) |
| 119 | crypto_free_tfm(tfm); |
| 120 | return status; |
| 121 | } |
NeilBrown | 190e4fb | 2005-06-23 22:04:25 -0700 | [diff] [blame^] | 122 | |
| 123 | typedef int (recdir_func)(struct dentry *, struct dentry *); |
| 124 | |
| 125 | struct dentry_list { |
| 126 | struct dentry *dentry; |
| 127 | struct list_head list; |
| 128 | }; |
| 129 | |
| 130 | struct dentry_list_arg { |
| 131 | struct list_head dentries; |
| 132 | struct dentry *parent; |
| 133 | }; |
| 134 | |
| 135 | static int |
| 136 | nfsd4_build_dentrylist(void *arg, const char *name, int namlen, |
| 137 | loff_t offset, ino_t ino, unsigned int d_type) |
| 138 | { |
| 139 | struct dentry_list_arg *dla = arg; |
| 140 | struct list_head *dentries = &dla->dentries; |
| 141 | struct dentry *parent = dla->parent; |
| 142 | struct dentry *dentry; |
| 143 | struct dentry_list *child; |
| 144 | |
| 145 | if (name && isdotent(name, namlen)) |
| 146 | return nfs_ok; |
| 147 | dentry = lookup_one_len(name, parent, namlen); |
| 148 | if (IS_ERR(dentry)) |
| 149 | return PTR_ERR(dentry); |
| 150 | child = kmalloc(sizeof(*child), GFP_KERNEL); |
| 151 | if (child == NULL) |
| 152 | return -ENOMEM; |
| 153 | child->dentry = dentry; |
| 154 | list_add(&child->list, dentries); |
| 155 | return 0; |
| 156 | } |
| 157 | |
| 158 | static int |
| 159 | nfsd4_list_rec_dir(struct dentry *dir, recdir_func *f) |
| 160 | { |
| 161 | struct file *filp; |
| 162 | struct dentry_list_arg dla = { |
| 163 | .parent = dir, |
| 164 | }; |
| 165 | struct list_head *dentries = &dla.dentries; |
| 166 | struct dentry_list *child; |
| 167 | uid_t uid; |
| 168 | gid_t gid; |
| 169 | int status; |
| 170 | |
| 171 | if (!rec_dir_init) |
| 172 | return 0; |
| 173 | |
| 174 | nfs4_save_user(&uid, &gid); |
| 175 | |
| 176 | filp = dentry_open(dget(dir), mntget(rec_dir.mnt), |
| 177 | O_RDWR); |
| 178 | status = PTR_ERR(filp); |
| 179 | if (IS_ERR(filp)) |
| 180 | goto out; |
| 181 | INIT_LIST_HEAD(dentries); |
| 182 | status = vfs_readdir(filp, nfsd4_build_dentrylist, &dla); |
| 183 | fput(filp); |
| 184 | while (!list_empty(dentries)) { |
| 185 | child = list_entry(dentries->next, struct dentry_list, list); |
| 186 | status = f(dir, child->dentry); |
| 187 | if (status) |
| 188 | goto out; |
| 189 | list_del(&child->list); |
| 190 | dput(child->dentry); |
| 191 | kfree(child); |
| 192 | } |
| 193 | out: |
| 194 | while (!list_empty(dentries)) { |
| 195 | child = list_entry(dentries->next, struct dentry_list, list); |
| 196 | list_del(&child->list); |
| 197 | dput(child->dentry); |
| 198 | kfree(child); |
| 199 | } |
| 200 | nfs4_reset_user(uid, gid); |
| 201 | return status; |
| 202 | } |
| 203 | |
| 204 | static int |
| 205 | load_recdir(struct dentry *parent, struct dentry *child) |
| 206 | { |
| 207 | if (child->d_name.len != HEXDIR_LEN - 1) { |
| 208 | printk("nfsd4: illegal name %s in recovery directory\n", |
| 209 | child->d_name.name); |
| 210 | /* Keep trying; maybe the others are OK: */ |
| 211 | return nfs_ok; |
| 212 | } |
| 213 | nfs4_client_to_reclaim(child->d_name.name); |
| 214 | return nfs_ok; |
| 215 | } |
| 216 | |
| 217 | int |
| 218 | nfsd4_recdir_load(void) { |
| 219 | int status; |
| 220 | |
| 221 | status = nfsd4_list_rec_dir(rec_dir.dentry, load_recdir); |
| 222 | if (status) |
| 223 | printk("nfsd4: failed loading clients from recovery" |
| 224 | " directory %s\n", rec_dir.dentry->d_name.name); |
| 225 | return status; |
| 226 | } |
| 227 | |
| 228 | /* |
| 229 | * Hold reference to the recovery directory. |
| 230 | */ |
| 231 | |
| 232 | void |
| 233 | nfsd4_init_recdir(char *rec_dirname) |
| 234 | { |
| 235 | uid_t uid = 0; |
| 236 | gid_t gid = 0; |
| 237 | int status; |
| 238 | |
| 239 | printk("NFSD: Using %s as the NFSv4 state recovery directory\n", |
| 240 | rec_dirname); |
| 241 | |
| 242 | BUG_ON(rec_dir_init); |
| 243 | |
| 244 | nfs4_save_user(&uid, &gid); |
| 245 | |
| 246 | status = path_lookup(rec_dirname, LOOKUP_FOLLOW, &rec_dir); |
| 247 | if (status == -ENOENT) |
| 248 | printk("NFSD: recovery directory %s doesn't exist\n", |
| 249 | rec_dirname); |
| 250 | |
| 251 | if (!status) |
| 252 | rec_dir_init = 1; |
| 253 | nfs4_reset_user(uid, gid); |
| 254 | } |
| 255 | |
| 256 | void |
| 257 | nfsd4_shutdown_recdir(void) |
| 258 | { |
| 259 | if (!rec_dir_init) |
| 260 | return; |
| 261 | rec_dir_init = 0; |
| 262 | path_release(&rec_dir); |
| 263 | } |