Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/fs/nfsd/nfsfh.c |
| 3 | * |
| 4 | * NFS server file handle treatment. |
| 5 | * |
| 6 | * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> |
| 7 | * Portions Copyright (C) 1999 G. Allen Morris III <gam3@acm.org> |
| 8 | * Extensive rewrite by Neil Brown <neilb@cse.unsw.edu.au> Southern-Spring 1999 |
| 9 | * ... and again Southern-Winter 2001 to support export_operations |
| 10 | */ |
| 11 | |
Christoph Hellwig | a569425 | 2007-07-17 04:04:28 -0700 | [diff] [blame] | 12 | #include <linux/exportfs.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | |
Andy Adamson | 32c1eb0 | 2007-07-17 04:04:48 -0700 | [diff] [blame] | 14 | #include <linux/sunrpc/svcauth_gss.h> |
Boaz Harrosh | 9a74af2 | 2009-12-03 20:30:56 +0200 | [diff] [blame] | 15 | #include "nfsd.h" |
J. Bruce Fields | 0a3adad | 2009-11-04 18:12:35 -0500 | [diff] [blame] | 16 | #include "vfs.h" |
J. Bruce Fields | 2e8138a | 2007-11-15 17:05:43 -0500 | [diff] [blame] | 17 | #include "auth.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | |
| 19 | #define NFSDDBG_FACILITY NFSDDBG_FH |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | |
| 21 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | /* |
| 23 | * our acceptability function. |
| 24 | * if NOSUBTREECHECK, accept anything |
| 25 | * if not, require that we can walk up to exp->ex_dentry |
| 26 | * doing some checks on the 'x' bits |
| 27 | */ |
| 28 | static int nfsd_acceptable(void *expv, struct dentry *dentry) |
| 29 | { |
| 30 | struct svc_export *exp = expv; |
| 31 | int rv; |
| 32 | struct dentry *tdentry; |
| 33 | struct dentry *parent; |
| 34 | |
| 35 | if (exp->ex_flags & NFSEXP_NOSUBTREECHECK) |
| 36 | return 1; |
| 37 | |
| 38 | tdentry = dget(dentry); |
Jan Blunck | 5477549 | 2008-02-14 19:38:39 -0800 | [diff] [blame] | 39 | while (tdentry != exp->ex_path.dentry && !IS_ROOT(tdentry)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | /* make sure parents give x permission to user */ |
| 41 | int err; |
| 42 | parent = dget_parent(tdentry); |
Al Viro | f419a2e | 2008-07-22 00:07:17 -0400 | [diff] [blame] | 43 | err = inode_permission(parent->d_inode, MAY_EXEC); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 44 | if (err < 0) { |
| 45 | dput(parent); |
| 46 | break; |
| 47 | } |
| 48 | dput(tdentry); |
| 49 | tdentry = parent; |
| 50 | } |
Jan Blunck | 5477549 | 2008-02-14 19:38:39 -0800 | [diff] [blame] | 51 | if (tdentry != exp->ex_path.dentry) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | dprintk("nfsd_acceptable failed at %p %s\n", tdentry, tdentry->d_name.name); |
Jan Blunck | 5477549 | 2008-02-14 19:38:39 -0800 | [diff] [blame] | 53 | rv = (tdentry == exp->ex_path.dentry); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 54 | dput(tdentry); |
| 55 | return rv; |
| 56 | } |
| 57 | |
| 58 | /* Type check. The correct error return for type mismatches does not seem to be |
| 59 | * generally agreed upon. SunOS seems to use EISDIR if file isn't S_IFREG; a |
| 60 | * comment in the NFSv3 spec says this is incorrect (implementation notes for |
| 61 | * the write call). |
| 62 | */ |
Al Viro | 83b1134 | 2006-10-19 23:28:55 -0700 | [diff] [blame] | 63 | static inline __be32 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 64 | nfsd_mode_check(struct svc_rqst *rqstp, umode_t mode, int type) |
| 65 | { |
| 66 | /* Type can be negative when creating hardlinks - not to a dir */ |
| 67 | if (type > 0 && (mode & S_IFMT) != type) { |
| 68 | if (rqstp->rq_vers == 4 && (mode & S_IFMT) == S_IFLNK) |
| 69 | return nfserr_symlink; |
| 70 | else if (type == S_IFDIR) |
| 71 | return nfserr_notdir; |
| 72 | else if ((mode & S_IFMT) == S_IFDIR) |
| 73 | return nfserr_isdir; |
| 74 | else |
| 75 | return nfserr_inval; |
| 76 | } |
| 77 | if (type < 0 && (mode & S_IFMT) == -type) { |
| 78 | if (rqstp->rq_vers == 4 && (mode & S_IFMT) == S_IFLNK) |
| 79 | return nfserr_symlink; |
| 80 | else if (type == -S_IFDIR) |
| 81 | return nfserr_isdir; |
| 82 | else |
| 83 | return nfserr_notdir; |
| 84 | } |
| 85 | return 0; |
| 86 | } |
| 87 | |
J. Bruce Fields | 6fa0283 | 2007-11-12 16:05:03 -0500 | [diff] [blame] | 88 | static __be32 nfsd_setuser_and_check_port(struct svc_rqst *rqstp, |
| 89 | struct svc_export *exp) |
| 90 | { |
J. Bruce Fields | 12045a6e | 2009-12-08 18:15:52 -0500 | [diff] [blame] | 91 | int flags = nfsexp_flags(rqstp, exp); |
| 92 | |
J. Bruce Fields | 6fa0283 | 2007-11-12 16:05:03 -0500 | [diff] [blame] | 93 | /* Check if the request originated from a secure port. */ |
J. Bruce Fields | 12045a6e | 2009-12-08 18:15:52 -0500 | [diff] [blame] | 94 | if (!rqstp->rq_secure && (flags & NFSEXP_INSECURE_PORT)) { |
Pavel Emelyanov | 5216a8e | 2008-02-21 10:57:45 +0300 | [diff] [blame] | 95 | RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]); |
J. Bruce Fields | 6fa0283 | 2007-11-12 16:05:03 -0500 | [diff] [blame] | 96 | dprintk(KERN_WARNING |
| 97 | "nfsd: request from insecure port %s!\n", |
| 98 | svc_print_addr(rqstp, buf, sizeof(buf))); |
| 99 | return nfserr_perm; |
| 100 | } |
| 101 | |
| 102 | /* Set user creds for this exportpoint */ |
| 103 | return nfserrno(nfsd_setuser(rqstp, exp)); |
| 104 | } |
| 105 | |
Steve Dickson | 03a816b | 2009-09-09 15:06:05 -0400 | [diff] [blame^] | 106 | static inline __be32 check_pseudo_root(struct svc_rqst *rqstp, |
| 107 | struct dentry *dentry, struct svc_export *exp) |
| 108 | { |
| 109 | if (!(exp->ex_flags & NFSEXP_V4ROOT)) |
| 110 | return nfs_ok; |
| 111 | /* |
| 112 | * v2/v3 clients have no need for the V4ROOT export--they use |
| 113 | * the mount protocl instead; also, further V4ROOT checks may be |
| 114 | * in v4-specific code, in which case v2/v3 clients could bypass |
| 115 | * them. |
| 116 | */ |
| 117 | if (!nfsd_v4client(rqstp)) |
| 118 | return nfserr_stale; |
| 119 | /* |
| 120 | * We're exposing only the directories and symlinks that have to be |
| 121 | * traversed on the way to real exports: |
| 122 | */ |
| 123 | if (unlikely(!S_ISDIR(dentry->d_inode->i_mode) && |
| 124 | !S_ISLNK(dentry->d_inode->i_mode))) |
| 125 | return nfserr_stale; |
| 126 | /* |
| 127 | * A pseudoroot export gives permission to access only one |
| 128 | * single directory; the kernel has to make another upcall |
| 129 | * before granting access to anything else under it: |
| 130 | */ |
| 131 | if (unlikely(dentry != exp->ex_path.dentry)) |
| 132 | return nfserr_stale; |
| 133 | return nfs_ok; |
| 134 | } |
| 135 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 136 | /* |
J. Bruce Fields | 03550fa | 2008-03-14 17:51:12 -0400 | [diff] [blame] | 137 | * Use the given filehandle to look up the corresponding export and |
| 138 | * dentry. On success, the results are used to set fh_export and |
| 139 | * fh_dentry. |
| 140 | */ |
| 141 | static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp) |
| 142 | { |
| 143 | struct knfsd_fh *fh = &fhp->fh_handle; |
| 144 | struct fid *fid = NULL, sfid; |
| 145 | struct svc_export *exp; |
| 146 | struct dentry *dentry; |
| 147 | int fileid_type; |
| 148 | int data_left = fh->fh_size/4; |
| 149 | __be32 error; |
| 150 | |
| 151 | error = nfserr_stale; |
| 152 | if (rqstp->rq_vers > 2) |
| 153 | error = nfserr_badhandle; |
| 154 | if (rqstp->rq_vers == 4 && fh->fh_size == 0) |
| 155 | return nfserr_nofilehandle; |
| 156 | |
| 157 | if (fh->fh_version == 1) { |
| 158 | int len; |
| 159 | |
| 160 | if (--data_left < 0) |
| 161 | return error; |
| 162 | if (fh->fh_auth_type != 0) |
| 163 | return error; |
| 164 | len = key_len(fh->fh_fsid_type) / 4; |
| 165 | if (len == 0) |
| 166 | return error; |
| 167 | if (fh->fh_fsid_type == FSID_MAJOR_MINOR) { |
| 168 | /* deprecated, convert to type 3 */ |
| 169 | len = key_len(FSID_ENCODE_DEV)/4; |
| 170 | fh->fh_fsid_type = FSID_ENCODE_DEV; |
| 171 | fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl(fh->fh_fsid[0]), ntohl(fh->fh_fsid[1]))); |
| 172 | fh->fh_fsid[1] = fh->fh_fsid[2]; |
| 173 | } |
| 174 | data_left -= len; |
| 175 | if (data_left < 0) |
| 176 | return error; |
| 177 | exp = rqst_exp_find(rqstp, fh->fh_fsid_type, fh->fh_auth); |
| 178 | fid = (struct fid *)(fh->fh_auth + len); |
| 179 | } else { |
| 180 | __u32 tfh[2]; |
| 181 | dev_t xdev; |
| 182 | ino_t xino; |
| 183 | |
| 184 | if (fh->fh_size != NFS_FHSIZE) |
| 185 | return error; |
| 186 | /* assume old filehandle format */ |
| 187 | xdev = old_decode_dev(fh->ofh_xdev); |
| 188 | xino = u32_to_ino_t(fh->ofh_xino); |
| 189 | mk_fsid(FSID_DEV, tfh, xdev, xino, 0, NULL); |
| 190 | exp = rqst_exp_find(rqstp, FSID_DEV, tfh); |
| 191 | } |
| 192 | |
| 193 | error = nfserr_stale; |
| 194 | if (PTR_ERR(exp) == -ENOENT) |
| 195 | return error; |
| 196 | |
| 197 | if (IS_ERR(exp)) |
| 198 | return nfserrno(PTR_ERR(exp)); |
| 199 | |
Neil Brown | 496d6c3 | 2008-05-08 13:03:09 +1000 | [diff] [blame] | 200 | if (exp->ex_flags & NFSEXP_NOSUBTREECHECK) { |
| 201 | /* Elevate privileges so that the lack of 'r' or 'x' |
| 202 | * permission on some parent directory will |
| 203 | * not stop exportfs_decode_fh from being able |
| 204 | * to reconnect a directory into the dentry cache. |
| 205 | * The same problem can affect "SUBTREECHECK" exports, |
| 206 | * but as nfsd_acceptable depends on correct |
| 207 | * access control settings being in effect, we cannot |
| 208 | * fix that case easily. |
| 209 | */ |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 210 | struct cred *new = prepare_creds(); |
| 211 | if (!new) |
| 212 | return nfserrno(-ENOMEM); |
| 213 | new->cap_effective = |
| 214 | cap_raise_nfsd_set(new->cap_effective, |
| 215 | new->cap_permitted); |
| 216 | put_cred(override_creds(new)); |
| 217 | put_cred(new); |
Neil Brown | 496d6c3 | 2008-05-08 13:03:09 +1000 | [diff] [blame] | 218 | } else { |
| 219 | error = nfsd_setuser_and_check_port(rqstp, exp); |
| 220 | if (error) |
| 221 | goto out; |
| 222 | } |
J. Bruce Fields | 03550fa | 2008-03-14 17:51:12 -0400 | [diff] [blame] | 223 | |
| 224 | /* |
| 225 | * Look up the dentry using the NFS file handle. |
| 226 | */ |
| 227 | error = nfserr_stale; |
| 228 | if (rqstp->rq_vers > 2) |
| 229 | error = nfserr_badhandle; |
| 230 | |
| 231 | if (fh->fh_version != 1) { |
| 232 | sfid.i32.ino = fh->ofh_ino; |
| 233 | sfid.i32.gen = fh->ofh_generation; |
| 234 | sfid.i32.parent_ino = fh->ofh_dirino; |
| 235 | fid = &sfid; |
| 236 | data_left = 3; |
| 237 | if (fh->ofh_dirino == 0) |
| 238 | fileid_type = FILEID_INO32_GEN; |
| 239 | else |
| 240 | fileid_type = FILEID_INO32_GEN_PARENT; |
| 241 | } else |
| 242 | fileid_type = fh->fh_fileid_type; |
| 243 | |
| 244 | if (fileid_type == FILEID_ROOT) |
| 245 | dentry = dget(exp->ex_path.dentry); |
| 246 | else { |
| 247 | dentry = exportfs_decode_fh(exp->ex_path.mnt, fid, |
| 248 | data_left, fileid_type, |
| 249 | nfsd_acceptable, exp); |
| 250 | } |
| 251 | if (dentry == NULL) |
| 252 | goto out; |
| 253 | if (IS_ERR(dentry)) { |
| 254 | if (PTR_ERR(dentry) != -EINVAL) |
| 255 | error = nfserrno(PTR_ERR(dentry)); |
| 256 | goto out; |
| 257 | } |
| 258 | |
| 259 | if (S_ISDIR(dentry->d_inode->i_mode) && |
| 260 | (dentry->d_flags & DCACHE_DISCONNECTED)) { |
| 261 | printk("nfsd: find_fh_dentry returned a DISCONNECTED directory: %s/%s\n", |
| 262 | dentry->d_parent->d_name.name, dentry->d_name.name); |
| 263 | } |
| 264 | |
| 265 | fhp->fh_dentry = dentry; |
| 266 | fhp->fh_export = exp; |
J. Bruce Fields | 03550fa | 2008-03-14 17:51:12 -0400 | [diff] [blame] | 267 | return 0; |
| 268 | out: |
| 269 | exp_put(exp); |
| 270 | return error; |
| 271 | } |
| 272 | |
J. Bruce Fields | b3d47676 | 2008-10-20 13:01:59 -0400 | [diff] [blame] | 273 | /** |
| 274 | * fh_verify - filehandle lookup and access checking |
| 275 | * @rqstp: pointer to current rpc request |
| 276 | * @fhp: filehandle to be verified |
| 277 | * @type: expected type of object pointed to by filehandle |
| 278 | * @access: type of access needed to object |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 279 | * |
J. Bruce Fields | b3d47676 | 2008-10-20 13:01:59 -0400 | [diff] [blame] | 280 | * Look up a dentry from the on-the-wire filehandle, check the client's |
| 281 | * access to the export, and set the current task's credentials. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 282 | * |
J. Bruce Fields | b3d47676 | 2008-10-20 13:01:59 -0400 | [diff] [blame] | 283 | * Regardless of success or failure of fh_verify(), fh_put() should be |
| 284 | * called on @fhp when the caller is finished with the filehandle. |
| 285 | * |
| 286 | * fh_verify() may be called multiple times on a given filehandle, for |
| 287 | * example, when processing an NFSv4 compound. The first call will look |
| 288 | * up a dentry using the on-the-wire filehandle. Subsequent calls will |
| 289 | * skip the lookup and just perform the other checks and possibly change |
| 290 | * the current task's credentials. |
| 291 | * |
| 292 | * @type specifies the type of object expected using one of the S_IF* |
| 293 | * constants defined in include/linux/stat.h. The caller may use zero |
| 294 | * to indicate that it doesn't care, or a negative integer to indicate |
| 295 | * that it expects something not of the given type. |
| 296 | * |
| 297 | * @access is formed from the NFSD_MAY_* constants defined in |
| 298 | * include/linux/nfsd/nfsd.h. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 299 | */ |
Al Viro | 83b1134 | 2006-10-19 23:28:55 -0700 | [diff] [blame] | 300 | __be32 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 301 | fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, int access) |
| 302 | { |
J. Bruce Fields | 03550fa | 2008-03-14 17:51:12 -0400 | [diff] [blame] | 303 | struct svc_export *exp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 304 | struct dentry *dentry; |
J. Bruce Fields | 03550fa | 2008-03-14 17:51:12 -0400 | [diff] [blame] | 305 | __be32 error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 306 | |
| 307 | dprintk("nfsd: fh_verify(%s)\n", SVCFH_fmt(fhp)); |
| 308 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 309 | if (!fhp->fh_dentry) { |
J. Bruce Fields | 03550fa | 2008-03-14 17:51:12 -0400 | [diff] [blame] | 310 | error = nfsd_set_fh_dentry(rqstp, fhp); |
NeilBrown | d1bbf14 | 2006-07-30 03:03:16 -0700 | [diff] [blame] | 311 | if (error) |
| 312 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 313 | } |
J. Bruce Fields | 864f0f6 | 2009-11-25 17:42:05 -0500 | [diff] [blame] | 314 | dentry = fhp->fh_dentry; |
| 315 | exp = fhp->fh_export; |
| 316 | /* |
| 317 | * We still have to do all these permission checks, even when |
| 318 | * fh_dentry is already set: |
| 319 | * - fh_verify may be called multiple times with different |
| 320 | * "access" arguments (e.g. nfsd_proc_create calls |
| 321 | * fh_verify(...,NFSD_MAY_EXEC) first, then later (in |
| 322 | * nfsd_create) calls fh_verify(...,NFSD_MAY_CREATE). |
| 323 | * - in the NFSv4 case, the filehandle may have been filled |
| 324 | * in by fh_compose, and given a dentry, but further |
| 325 | * compound operations performed with that filehandle |
| 326 | * still need permissions checks. In the worst case, a |
| 327 | * mountpoint crossing may have changed the export |
| 328 | * options, and we may now need to use a different uid |
| 329 | * (for example, if different id-squashing options are in |
| 330 | * effect on the new filesystem). |
| 331 | */ |
Steve Dickson | 03a816b | 2009-09-09 15:06:05 -0400 | [diff] [blame^] | 332 | error = check_pseudo_root(rqstp, dentry, exp); |
| 333 | if (error) |
| 334 | goto out; |
| 335 | |
J. Bruce Fields | 864f0f6 | 2009-11-25 17:42:05 -0500 | [diff] [blame] | 336 | error = nfsd_setuser_and_check_port(rqstp, exp); |
| 337 | if (error) |
| 338 | goto out; |
J. Bruce Fields | 7fc90ec | 2006-06-30 01:56:14 -0700 | [diff] [blame] | 339 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 340 | error = nfsd_mode_check(rqstp, dentry->d_inode->i_mode, type); |
| 341 | if (error) |
| 342 | goto out; |
| 343 | |
J. Bruce Fields | 04716e6 | 2008-08-07 13:00:20 -0400 | [diff] [blame] | 344 | /* |
| 345 | * pseudoflavor restrictions are not enforced on NLM, |
| 346 | * which clients virtually always use auth_sys for, |
| 347 | * even while using RPCSEC_GSS for NFS. |
| 348 | */ |
| 349 | if (access & NFSD_MAY_LOCK) |
| 350 | goto skip_pseudoflavor_check; |
| 351 | /* |
| 352 | * Clients may expect to be able to use auth_sys during mount, |
| 353 | * even if they use gss for everything else; see section 2.3.2 |
| 354 | * of rfc 2623. |
| 355 | */ |
| 356 | if (access & NFSD_MAY_BYPASS_GSS_ON_ROOT |
| 357 | && exp->ex_path.dentry == dentry) |
| 358 | goto skip_pseudoflavor_check; |
Andy Adamson | 32c1eb0 | 2007-07-17 04:04:48 -0700 | [diff] [blame] | 359 | |
J. Bruce Fields | 04716e6 | 2008-08-07 13:00:20 -0400 | [diff] [blame] | 360 | error = check_nfsd_access(exp, rqstp); |
| 361 | if (error) |
| 362 | goto out; |
| 363 | |
| 364 | skip_pseudoflavor_check: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 365 | /* Finally, check access permissions. */ |
J. Bruce Fields | 0ec757d | 2007-07-17 04:04:48 -0700 | [diff] [blame] | 366 | error = nfsd_permission(rqstp, exp, dentry, access); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 367 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 368 | if (error) { |
NeilBrown | 34e9a63 | 2007-01-29 13:19:52 -0800 | [diff] [blame] | 369 | dprintk("fh_verify: %s/%s permission failure, " |
| 370 | "acc=%x, error=%d\n", |
| 371 | dentry->d_parent->d_name.name, |
| 372 | dentry->d_name.name, |
Al Viro | fc2dd2e | 2007-02-01 13:52:43 +0000 | [diff] [blame] | 373 | access, ntohl(error)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 374 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 375 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 376 | if (error == nfserr_stale) |
| 377 | nfsdstats.fh_stale++; |
| 378 | return error; |
| 379 | } |
| 380 | |
| 381 | |
| 382 | /* |
| 383 | * Compose a file handle for an NFS reply. |
| 384 | * |
| 385 | * Note that when first composed, the dentry may not yet have |
| 386 | * an inode. In this case a call to fh_update should be made |
| 387 | * before the fh goes out on the wire ... |
| 388 | */ |
Christoph Hellwig | 6e91ea2 | 2007-10-21 16:42:03 -0700 | [diff] [blame] | 389 | static void _fh_update(struct svc_fh *fhp, struct svc_export *exp, |
| 390 | struct dentry *dentry) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 391 | { |
Jan Blunck | 5477549 | 2008-02-14 19:38:39 -0800 | [diff] [blame] | 392 | if (dentry != exp->ex_path.dentry) { |
Christoph Hellwig | 6e91ea2 | 2007-10-21 16:42:03 -0700 | [diff] [blame] | 393 | struct fid *fid = (struct fid *) |
| 394 | (fhp->fh_handle.fh_auth + fhp->fh_handle.fh_size/4 - 1); |
| 395 | int maxsize = (fhp->fh_maxsize - fhp->fh_handle.fh_size)/4; |
| 396 | int subtreecheck = !(exp->ex_flags & NFSEXP_NOSUBTREECHECK); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 397 | |
Christoph Hellwig | 6e91ea2 | 2007-10-21 16:42:03 -0700 | [diff] [blame] | 398 | fhp->fh_handle.fh_fileid_type = |
| 399 | exportfs_encode_fh(dentry, fid, &maxsize, subtreecheck); |
| 400 | fhp->fh_handle.fh_size += maxsize * 4; |
| 401 | } else { |
| 402 | fhp->fh_handle.fh_fileid_type = FILEID_ROOT; |
| 403 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 404 | } |
| 405 | |
| 406 | /* |
| 407 | * for composing old style file handles |
| 408 | */ |
| 409 | static inline void _fh_update_old(struct dentry *dentry, |
| 410 | struct svc_export *exp, |
| 411 | struct knfsd_fh *fh) |
| 412 | { |
| 413 | fh->ofh_ino = ino_t_to_u32(dentry->d_inode->i_ino); |
| 414 | fh->ofh_generation = dentry->d_inode->i_generation; |
| 415 | if (S_ISDIR(dentry->d_inode->i_mode) || |
| 416 | (exp->ex_flags & NFSEXP_NOSUBTREECHECK)) |
| 417 | fh->ofh_dirino = 0; |
| 418 | } |
| 419 | |
J. Bruce Fields | 8e49875 | 2009-09-02 19:31:32 -0400 | [diff] [blame] | 420 | static bool is_root_export(struct svc_export *exp) |
| 421 | { |
| 422 | return exp->ex_path.dentry == exp->ex_path.dentry->d_sb->s_root; |
| 423 | } |
| 424 | |
| 425 | static struct super_block *exp_sb(struct svc_export *exp) |
| 426 | { |
| 427 | return exp->ex_path.dentry->d_inode->i_sb; |
| 428 | } |
| 429 | |
| 430 | static bool fsid_type_ok_for_exp(u8 fsid_type, struct svc_export *exp) |
| 431 | { |
| 432 | switch (fsid_type) { |
| 433 | case FSID_DEV: |
| 434 | if (!old_valid_dev(exp_sb(exp)->s_dev)) |
| 435 | return 0; |
| 436 | /* FALL THROUGH */ |
| 437 | case FSID_MAJOR_MINOR: |
| 438 | case FSID_ENCODE_DEV: |
| 439 | return exp_sb(exp)->s_type->fs_flags & FS_REQUIRES_DEV; |
| 440 | case FSID_NUM: |
| 441 | return exp->ex_flags & NFSEXP_FSID; |
| 442 | case FSID_UUID8: |
| 443 | case FSID_UUID16: |
| 444 | if (!is_root_export(exp)) |
| 445 | return 0; |
| 446 | /* fall through */ |
| 447 | case FSID_UUID4_INUM: |
| 448 | case FSID_UUID16_INUM: |
| 449 | return exp->ex_uuid != NULL; |
| 450 | } |
| 451 | return 1; |
| 452 | } |
| 453 | |
J. Bruce Fields | bc6c53d | 2009-09-02 19:50:40 -0400 | [diff] [blame] | 454 | |
| 455 | static void set_version_and_fsid_type(struct svc_fh *fhp, struct svc_export *exp, struct svc_fh *ref_fh) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 456 | { |
NeilBrown | b41eeef | 2007-05-09 02:34:57 -0700 | [diff] [blame] | 457 | u8 version; |
J. Bruce Fields | bc6c53d | 2009-09-02 19:50:40 -0400 | [diff] [blame] | 458 | u8 fsid_type; |
| 459 | retry: |
NeilBrown | b41eeef | 2007-05-09 02:34:57 -0700 | [diff] [blame] | 460 | version = 1; |
NeilBrown | 7e40536 | 2006-06-30 01:56:12 -0700 | [diff] [blame] | 461 | if (ref_fh && ref_fh->fh_export == exp) { |
NeilBrown | 982aedf | 2007-02-14 00:33:11 -0800 | [diff] [blame] | 462 | version = ref_fh->fh_handle.fh_version; |
NeilBrown | b41eeef | 2007-05-09 02:34:57 -0700 | [diff] [blame] | 463 | fsid_type = ref_fh->fh_handle.fh_fsid_type; |
| 464 | |
NeilBrown | b41eeef | 2007-05-09 02:34:57 -0700 | [diff] [blame] | 465 | ref_fh = NULL; |
| 466 | |
| 467 | switch (version) { |
| 468 | case 0xca: |
NeilBrown | af6a4e2 | 2007-02-14 00:33:12 -0800 | [diff] [blame] | 469 | fsid_type = FSID_DEV; |
NeilBrown | b41eeef | 2007-05-09 02:34:57 -0700 | [diff] [blame] | 470 | break; |
| 471 | case 1: |
| 472 | break; |
| 473 | default: |
| 474 | goto retry; |
| 475 | } |
| 476 | |
J. Bruce Fields | 8e49875 | 2009-09-02 19:31:32 -0400 | [diff] [blame] | 477 | /* |
| 478 | * As the fsid -> filesystem mapping was guided by |
| 479 | * user-space, there is no guarantee that the filesystem |
| 480 | * actually supports that fsid type. If it doesn't we |
| 481 | * loop around again without ref_fh set. |
NeilBrown | 982aedf | 2007-02-14 00:33:11 -0800 | [diff] [blame] | 482 | */ |
J. Bruce Fields | 8e49875 | 2009-09-02 19:31:32 -0400 | [diff] [blame] | 483 | if (!fsid_type_ok_for_exp(fsid_type, exp)) |
| 484 | goto retry; |
Steve Dickson | 30fa8c0 | 2009-01-07 16:54:30 -0500 | [diff] [blame] | 485 | } else if (exp->ex_flags & NFSEXP_FSID) { |
| 486 | fsid_type = FSID_NUM; |
NeilBrown | af6a4e2 | 2007-02-14 00:33:12 -0800 | [diff] [blame] | 487 | } else if (exp->ex_uuid) { |
| 488 | if (fhp->fh_maxsize >= 64) { |
J. Bruce Fields | 8e49875 | 2009-09-02 19:31:32 -0400 | [diff] [blame] | 489 | if (is_root_export(exp)) |
NeilBrown | af6a4e2 | 2007-02-14 00:33:12 -0800 | [diff] [blame] | 490 | fsid_type = FSID_UUID16; |
| 491 | else |
| 492 | fsid_type = FSID_UUID16_INUM; |
| 493 | } else { |
J. Bruce Fields | 8e49875 | 2009-09-02 19:31:32 -0400 | [diff] [blame] | 494 | if (is_root_export(exp)) |
NeilBrown | af6a4e2 | 2007-02-14 00:33:12 -0800 | [diff] [blame] | 495 | fsid_type = FSID_UUID8; |
| 496 | else |
| 497 | fsid_type = FSID_UUID4_INUM; |
| 498 | } |
J. Bruce Fields | bc6c53d | 2009-09-02 19:50:40 -0400 | [diff] [blame] | 499 | } else if (!old_valid_dev(exp_sb(exp)->s_dev)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 500 | /* for newer device numbers, we must use a newer fsid format */ |
NeilBrown | af6a4e2 | 2007-02-14 00:33:12 -0800 | [diff] [blame] | 501 | fsid_type = FSID_ENCODE_DEV; |
NeilBrown | 982aedf | 2007-02-14 00:33:11 -0800 | [diff] [blame] | 502 | else |
NeilBrown | af6a4e2 | 2007-02-14 00:33:12 -0800 | [diff] [blame] | 503 | fsid_type = FSID_DEV; |
J. Bruce Fields | bc6c53d | 2009-09-02 19:50:40 -0400 | [diff] [blame] | 504 | fhp->fh_handle.fh_version = version; |
| 505 | if (version) |
| 506 | fhp->fh_handle.fh_fsid_type = fsid_type; |
| 507 | } |
| 508 | |
| 509 | __be32 |
| 510 | fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry, |
| 511 | struct svc_fh *ref_fh) |
| 512 | { |
| 513 | /* ref_fh is a reference file handle. |
| 514 | * if it is non-null and for the same filesystem, then we should compose |
| 515 | * a filehandle which is of the same version, where possible. |
| 516 | * Currently, that means that if ref_fh->fh_handle.fh_version == 0xca |
| 517 | * Then create a 32byte filehandle using nfs_fhbase_old |
| 518 | * |
| 519 | */ |
| 520 | |
| 521 | struct inode * inode = dentry->d_inode; |
| 522 | struct dentry *parent = dentry->d_parent; |
| 523 | __u32 *datap; |
| 524 | dev_t ex_dev = exp_sb(exp)->s_dev; |
| 525 | |
| 526 | dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %s/%s, ino=%ld)\n", |
| 527 | MAJOR(ex_dev), MINOR(ex_dev), |
| 528 | (long) exp->ex_path.dentry->d_inode->i_ino, |
| 529 | parent->d_name.name, dentry->d_name.name, |
| 530 | (inode ? inode->i_ino : 0)); |
| 531 | |
| 532 | /* Choose filehandle version and fsid type based on |
| 533 | * the reference filehandle (if it is in the same export) |
| 534 | * or the export options. |
| 535 | */ |
| 536 | set_version_and_fsid_type(fhp, exp, ref_fh); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 537 | |
| 538 | if (ref_fh == fhp) |
| 539 | fh_put(ref_fh); |
| 540 | |
| 541 | if (fhp->fh_locked || fhp->fh_dentry) { |
| 542 | printk(KERN_ERR "fh_compose: fh %s/%s not initialized!\n", |
NeilBrown | 982aedf | 2007-02-14 00:33:11 -0800 | [diff] [blame] | 543 | parent->d_name.name, dentry->d_name.name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 544 | } |
| 545 | if (fhp->fh_maxsize < NFS_FHSIZE) |
| 546 | printk(KERN_ERR "fh_compose: called with maxsize %d! %s/%s\n", |
NeilBrown | 982aedf | 2007-02-14 00:33:11 -0800 | [diff] [blame] | 547 | fhp->fh_maxsize, |
| 548 | parent->d_name.name, dentry->d_name.name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 549 | |
| 550 | fhp->fh_dentry = dget(dentry); /* our internal copy */ |
| 551 | fhp->fh_export = exp; |
| 552 | cache_get(&exp->h); |
| 553 | |
J. Bruce Fields | bc6c53d | 2009-09-02 19:50:40 -0400 | [diff] [blame] | 554 | if (fhp->fh_handle.fh_version == 0xca) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 555 | /* old style filehandle please */ |
| 556 | memset(&fhp->fh_handle.fh_base, 0, NFS_FHSIZE); |
| 557 | fhp->fh_handle.fh_size = NFS_FHSIZE; |
| 558 | fhp->fh_handle.ofh_dcookie = 0xfeebbaca; |
| 559 | fhp->fh_handle.ofh_dev = old_encode_dev(ex_dev); |
| 560 | fhp->fh_handle.ofh_xdev = fhp->fh_handle.ofh_dev; |
NeilBrown | 982aedf | 2007-02-14 00:33:11 -0800 | [diff] [blame] | 561 | fhp->fh_handle.ofh_xino = |
Jan Blunck | 5477549 | 2008-02-14 19:38:39 -0800 | [diff] [blame] | 562 | ino_t_to_u32(exp->ex_path.dentry->d_inode->i_ino); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 563 | fhp->fh_handle.ofh_dirino = ino_t_to_u32(parent_ino(dentry)); |
| 564 | if (inode) |
| 565 | _fh_update_old(dentry, exp, &fhp->fh_handle); |
| 566 | } else { |
| 567 | int len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 568 | fhp->fh_handle.fh_auth_type = 0; |
| 569 | datap = fhp->fh_handle.fh_auth+0; |
J. Bruce Fields | bc6c53d | 2009-09-02 19:50:40 -0400 | [diff] [blame] | 570 | mk_fsid(fhp->fh_handle.fh_fsid_type, datap, ex_dev, |
Jan Blunck | 5477549 | 2008-02-14 19:38:39 -0800 | [diff] [blame] | 571 | exp->ex_path.dentry->d_inode->i_ino, |
NeilBrown | af6a4e2 | 2007-02-14 00:33:12 -0800 | [diff] [blame] | 572 | exp->ex_fsid, exp->ex_uuid); |
| 573 | |
J. Bruce Fields | bc6c53d | 2009-09-02 19:50:40 -0400 | [diff] [blame] | 574 | len = key_len(fhp->fh_handle.fh_fsid_type); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 575 | datap += len/4; |
| 576 | fhp->fh_handle.fh_size = 4 + len; |
| 577 | |
Christoph Hellwig | 6e91ea2 | 2007-10-21 16:42:03 -0700 | [diff] [blame] | 578 | if (inode) |
| 579 | _fh_update(fhp, exp, dentry); |
J. Bruce Fields | 1be10a8 | 2009-09-04 11:59:32 -0400 | [diff] [blame] | 580 | if (fhp->fh_handle.fh_fileid_type == 255) { |
| 581 | fh_put(fhp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 582 | return nfserr_opnotsupp; |
J. Bruce Fields | 1be10a8 | 2009-09-04 11:59:32 -0400 | [diff] [blame] | 583 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 584 | } |
| 585 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 586 | return 0; |
| 587 | } |
| 588 | |
| 589 | /* |
| 590 | * Update file handle information after changing a dentry. |
| 591 | * This is only called by nfsd_create, nfsd_create_v3 and nfsd_proc_create |
| 592 | */ |
Al Viro | 83b1134 | 2006-10-19 23:28:55 -0700 | [diff] [blame] | 593 | __be32 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 594 | fh_update(struct svc_fh *fhp) |
| 595 | { |
| 596 | struct dentry *dentry; |
NeilBrown | 982aedf | 2007-02-14 00:33:11 -0800 | [diff] [blame] | 597 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 598 | if (!fhp->fh_dentry) |
| 599 | goto out_bad; |
| 600 | |
| 601 | dentry = fhp->fh_dentry; |
| 602 | if (!dentry->d_inode) |
| 603 | goto out_negative; |
| 604 | if (fhp->fh_handle.fh_version != 1) { |
| 605 | _fh_update_old(dentry, fhp->fh_export, &fhp->fh_handle); |
| 606 | } else { |
Christoph Hellwig | 6e91ea2 | 2007-10-21 16:42:03 -0700 | [diff] [blame] | 607 | if (fhp->fh_handle.fh_fileid_type != FILEID_ROOT) |
NeilBrown | 4c9608b | 2006-06-30 01:56:11 -0700 | [diff] [blame] | 608 | goto out; |
Christoph Hellwig | 6e91ea2 | 2007-10-21 16:42:03 -0700 | [diff] [blame] | 609 | |
| 610 | _fh_update(fhp, fhp->fh_export, dentry); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 611 | if (fhp->fh_handle.fh_fileid_type == 255) |
| 612 | return nfserr_opnotsupp; |
| 613 | } |
| 614 | out: |
| 615 | return 0; |
| 616 | |
| 617 | out_bad: |
| 618 | printk(KERN_ERR "fh_update: fh not verified!\n"); |
| 619 | goto out; |
| 620 | out_negative: |
| 621 | printk(KERN_ERR "fh_update: %s/%s still negative!\n", |
| 622 | dentry->d_parent->d_name.name, dentry->d_name.name); |
| 623 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 624 | } |
| 625 | |
| 626 | /* |
| 627 | * Release a file handle. |
| 628 | */ |
| 629 | void |
| 630 | fh_put(struct svc_fh *fhp) |
| 631 | { |
| 632 | struct dentry * dentry = fhp->fh_dentry; |
| 633 | struct svc_export * exp = fhp->fh_export; |
| 634 | if (dentry) { |
| 635 | fh_unlock(fhp); |
| 636 | fhp->fh_dentry = NULL; |
| 637 | dput(dentry); |
| 638 | #ifdef CONFIG_NFSD_V3 |
| 639 | fhp->fh_pre_saved = 0; |
| 640 | fhp->fh_post_saved = 0; |
| 641 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 642 | } |
| 643 | if (exp) { |
NeilBrown | baab935 | 2006-03-27 01:15:09 -0800 | [diff] [blame] | 644 | cache_put(&exp->h, &svc_export_cache); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 645 | fhp->fh_export = NULL; |
| 646 | } |
| 647 | return; |
| 648 | } |
| 649 | |
| 650 | /* |
| 651 | * Shorthand for dprintk()'s |
| 652 | */ |
| 653 | char * SVCFH_fmt(struct svc_fh *fhp) |
| 654 | { |
| 655 | struct knfsd_fh *fh = &fhp->fh_handle; |
| 656 | |
| 657 | static char buf[80]; |
| 658 | sprintf(buf, "%d: %08x %08x %08x %08x %08x %08x", |
| 659 | fh->fh_size, |
| 660 | fh->fh_base.fh_pad[0], |
| 661 | fh->fh_base.fh_pad[1], |
| 662 | fh->fh_base.fh_pad[2], |
| 663 | fh->fh_base.fh_pad[3], |
| 664 | fh->fh_base.fh_pad[4], |
| 665 | fh->fh_base.fh_pad[5]); |
| 666 | return buf; |
| 667 | } |
NeilBrown | af6a4e2 | 2007-02-14 00:33:12 -0800 | [diff] [blame] | 668 | |
| 669 | enum fsid_source fsid_source(struct svc_fh *fhp) |
| 670 | { |
| 671 | if (fhp->fh_handle.fh_version != 1) |
| 672 | return FSIDSOURCE_DEV; |
| 673 | switch(fhp->fh_handle.fh_fsid_type) { |
| 674 | case FSID_DEV: |
| 675 | case FSID_ENCODE_DEV: |
| 676 | case FSID_MAJOR_MINOR: |
J. Bruce Fields | 8e49875 | 2009-09-02 19:31:32 -0400 | [diff] [blame] | 677 | if (exp_sb(fhp->fh_export)->s_type->fs_flags & FS_REQUIRES_DEV) |
Neil Brown | b8da0d1 | 2007-09-05 17:22:13 -0400 | [diff] [blame] | 678 | return FSIDSOURCE_DEV; |
| 679 | break; |
NeilBrown | af6a4e2 | 2007-02-14 00:33:12 -0800 | [diff] [blame] | 680 | case FSID_NUM: |
NeilBrown | af6a4e2 | 2007-02-14 00:33:12 -0800 | [diff] [blame] | 681 | if (fhp->fh_export->ex_flags & NFSEXP_FSID) |
| 682 | return FSIDSOURCE_FSID; |
Neil Brown | b8da0d1 | 2007-09-05 17:22:13 -0400 | [diff] [blame] | 683 | break; |
| 684 | default: |
| 685 | break; |
NeilBrown | af6a4e2 | 2007-02-14 00:33:12 -0800 | [diff] [blame] | 686 | } |
Neil Brown | b8da0d1 | 2007-09-05 17:22:13 -0400 | [diff] [blame] | 687 | /* either a UUID type filehandle, or the filehandle doesn't |
| 688 | * match the export. |
| 689 | */ |
| 690 | if (fhp->fh_export->ex_flags & NFSEXP_FSID) |
| 691 | return FSIDSOURCE_FSID; |
| 692 | if (fhp->fh_export->ex_uuid) |
| 693 | return FSIDSOURCE_UUID; |
| 694 | return FSIDSOURCE_DEV; |
NeilBrown | af6a4e2 | 2007-02-14 00:33:12 -0800 | [diff] [blame] | 695 | } |