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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 | // SPDX-License-Identifier: GPL-2.0-or-later /* Extended attribute handling for AFS. We use xattrs to get and set metadata * instead of providing pioctl(). * * Copyright (C) 2017 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) */ #include <linux/slab.h> #include <linux/fs.h> #include <linux/xattr.h> #include "internal.h" /* * Get a file's ACL. */ static int afs_xattr_get_acl(const struct xattr_handler *handler, struct dentry *dentry, struct inode *inode, const char *name, void *buffer, size_t size) { struct afs_fs_cursor fc; struct afs_status_cb *scb; struct afs_vnode *vnode = AFS_FS_I(inode); struct afs_acl *acl = NULL; struct key *key; int ret = -ENOMEM; scb = kzalloc(sizeof(struct afs_status_cb), GFP_NOFS); if (!scb) goto error; key = afs_request_key(vnode->volume->cell); if (IS_ERR(key)) { ret = PTR_ERR(key); goto error_scb; } ret = -ERESTARTSYS; if (afs_begin_vnode_operation(&fc, vnode, key, true)) { afs_dataversion_t data_version = vnode->status.data_version; while (afs_select_fileserver(&fc)) { fc.cb_break = afs_calc_vnode_cb_break(vnode); acl = afs_fs_fetch_acl(&fc, scb); } afs_check_for_remote_deletion(&fc, fc.vnode); afs_vnode_commit_status(&fc, vnode, fc.cb_break, &data_version, scb); ret = afs_end_vnode_operation(&fc); } if (ret == 0) { ret = acl->size; if (size > 0) { if (acl->size <= size) memcpy(buffer, acl->data, acl->size); else ret = -ERANGE; } kfree(acl); } key_put(key); error_scb: kfree(scb); error: return ret; } /* * Set a file's AFS3 ACL. */ static int afs_xattr_set_acl(const struct xattr_handler *handler, struct dentry *dentry, struct inode *inode, const char *name, const void *buffer, size_t size, int flags) { struct afs_fs_cursor fc; struct afs_status_cb *scb; struct afs_vnode *vnode = AFS_FS_I(inode); struct afs_acl *acl = NULL; struct key *key; int ret = -ENOMEM; if (flags == XATTR_CREATE) return -EINVAL; scb = kzalloc(sizeof(struct afs_status_cb), GFP_NOFS); if (!scb) goto error; acl = kmalloc(sizeof(*acl) + size, GFP_KERNEL); if (!acl) goto error_scb; key = afs_request_key(vnode->volume->cell); if (IS_ERR(key)) { ret = PTR_ERR(key); goto error_acl; } acl->size = size; memcpy(acl->data, buffer, size); ret = -ERESTARTSYS; if (afs_begin_vnode_operation(&fc, vnode, key, true)) { afs_dataversion_t data_version = vnode->status.data_version; while (afs_select_fileserver(&fc)) { fc.cb_break = afs_calc_vnode_cb_break(vnode); afs_fs_store_acl(&fc, acl, scb); } afs_check_for_remote_deletion(&fc, fc.vnode); afs_vnode_commit_status(&fc, vnode, fc.cb_break, &data_version, scb); ret = afs_end_vnode_operation(&fc); } key_put(key); error_acl: kfree(acl); error_scb: kfree(scb); error: return ret; } static const struct xattr_handler afs_xattr_afs_acl_handler = { .name = "afs.acl", .get = afs_xattr_get_acl, .set = afs_xattr_set_acl, }; /* * Get a file's YFS ACL. */ static int afs_xattr_get_yfs(const struct xattr_handler *handler, struct dentry *dentry, struct inode *inode, const char *name, void *buffer, size_t size) { struct afs_fs_cursor fc; struct afs_status_cb *scb; struct afs_vnode *vnode = AFS_FS_I(inode); struct yfs_acl *yacl = NULL; struct key *key; char buf[16], *data; int which = 0, dsize, ret = -ENOMEM; if (strcmp(name, "acl") == 0) which = 0; else if (strcmp(name, "acl_inherited") == 0) which = 1; else if (strcmp(name, "acl_num_cleaned") == 0) which = 2; else if (strcmp(name, "vol_acl") == 0) which = 3; else return -EOPNOTSUPP; yacl = kzalloc(sizeof(struct yfs_acl), GFP_KERNEL); if (!yacl) goto error; if (which == 0) yacl->flags |= YFS_ACL_WANT_ACL; else if (which == 3) yacl->flags |= YFS_ACL_WANT_VOL_ACL; scb = kzalloc(sizeof(struct afs_status_cb), GFP_NOFS); if (!scb) goto error_yacl; key = afs_request_key(vnode->volume->cell); if (IS_ERR(key)) { ret = PTR_ERR(key); goto error_scb; } ret = -ERESTARTSYS; if (afs_begin_vnode_operation(&fc, vnode, key, true)) { afs_dataversion_t data_version = vnode->status.data_version; while (afs_select_fileserver(&fc)) { fc.cb_break = afs_calc_vnode_cb_break(vnode); yfs_fs_fetch_opaque_acl(&fc, yacl, scb); } afs_check_for_remote_deletion(&fc, fc.vnode); afs_vnode_commit_status(&fc, vnode, fc.cb_break, &data_version, scb); ret = afs_end_vnode_operation(&fc); } if (ret < 0) goto error_key; switch (which) { case 0: data = yacl->acl->data; dsize = yacl->acl->size; break; case 1: data = buf; dsize = snprintf(buf, sizeof(buf), "%u", yacl->inherit_flag); break; case 2: data = buf; dsize = snprintf(buf, sizeof(buf), "%u", yacl->num_cleaned); break; case 3: data = yacl->vol_acl->data; dsize = yacl->vol_acl->size; break; default: ret = -EOPNOTSUPP; goto error_key; } ret = dsize; if (size > 0) { if (dsize > size) { ret = -ERANGE; goto error_key; } memcpy(buffer, data, dsize); } error_key: key_put(key); error_scb: kfree(scb); error_yacl: yfs_free_opaque_acl(yacl); error: return ret; } /* * Set a file's YFS ACL. */ static int afs_xattr_set_yfs(const struct xattr_handler *handler, struct dentry *dentry, struct inode *inode, const char *name, const void *buffer, size_t size, int flags) { struct afs_fs_cursor fc; struct afs_status_cb *scb; struct afs_vnode *vnode = AFS_FS_I(inode); struct afs_acl *acl = NULL; struct key *key; int ret = -ENOMEM; if (flags == XATTR_CREATE || strcmp(name, "acl") != 0) return -EINVAL; scb = kzalloc(sizeof(struct afs_status_cb), GFP_NOFS); if (!scb) goto error; acl = kmalloc(sizeof(*acl) + size, GFP_KERNEL); if (!acl) goto error_scb; acl->size = size; memcpy(acl->data, buffer, size); key = afs_request_key(vnode->volume->cell); if (IS_ERR(key)) { ret = PTR_ERR(key); goto error_acl; } ret = -ERESTARTSYS; if (afs_begin_vnode_operation(&fc, vnode, key, true)) { afs_dataversion_t data_version = vnode->status.data_version; while (afs_select_fileserver(&fc)) { fc.cb_break = afs_calc_vnode_cb_break(vnode); yfs_fs_store_opaque_acl2(&fc, acl, scb); } afs_check_for_remote_deletion(&fc, fc.vnode); afs_vnode_commit_status(&fc, vnode, fc.cb_break, &data_version, scb); ret = afs_end_vnode_operation(&fc); } error_acl: kfree(acl); key_put(key); error_scb: kfree(scb); error: return ret; } static const struct xattr_handler afs_xattr_yfs_handler = { .prefix = "afs.yfs.", .get = afs_xattr_get_yfs, .set = afs_xattr_set_yfs, }; /* * Get the name of the cell on which a file resides. */ static int afs_xattr_get_cell(const struct xattr_handler *handler, struct dentry *dentry, struct inode *inode, const char *name, void *buffer, size_t size) { struct afs_vnode *vnode = AFS_FS_I(inode); struct afs_cell *cell = vnode->volume->cell; size_t namelen; namelen = cell->name_len; if (size == 0) return namelen; if (namelen > size) return -ERANGE; memcpy(buffer, cell->name, namelen); return namelen; } static const struct xattr_handler afs_xattr_afs_cell_handler = { .name = "afs.cell", .get = afs_xattr_get_cell, }; /* * Get the volume ID, vnode ID and vnode uniquifier of a file as a sequence of * hex numbers separated by colons. */ static int afs_xattr_get_fid(const struct xattr_handler *handler, struct dentry *dentry, struct inode *inode, const char *name, void *buffer, size_t size) { struct afs_vnode *vnode = AFS_FS_I(inode); char text[16 + 1 + 24 + 1 + 8 + 1]; size_t len; /* The volume ID is 64-bit, the vnode ID is 96-bit and the * uniquifier is 32-bit. */ len = sprintf(text, "%llx:", vnode->fid.vid); if (vnode->fid.vnode_hi) len += sprintf(text + len, "%x%016llx", vnode->fid.vnode_hi, vnode->fid.vnode); else len += sprintf(text + len, "%llx", vnode->fid.vnode); len += sprintf(text + len, ":%x", vnode->fid.unique); if (size == 0) return len; if (len > size) return -ERANGE; memcpy(buffer, text, len); return len; } static const struct xattr_handler afs_xattr_afs_fid_handler = { .name = "afs.fid", .get = afs_xattr_get_fid, }; /* * Get the name of the volume on which a file resides. */ static int afs_xattr_get_volume(const struct xattr_handler *handler, struct dentry *dentry, struct inode *inode, const char *name, void *buffer, size_t size) { struct afs_vnode *vnode = AFS_FS_I(inode); const char *volname = vnode->volume->name; size_t namelen; namelen = strlen(volname); if (size == 0) return namelen; if (namelen > size) return -ERANGE; memcpy(buffer, volname, namelen); return namelen; } static const struct xattr_handler afs_xattr_afs_volume_handler = { .name = "afs.volume", .get = afs_xattr_get_volume, }; const struct xattr_handler *afs_xattr_handlers[] = { &afs_xattr_afs_acl_handler, &afs_xattr_afs_cell_handler, &afs_xattr_afs_fid_handler, &afs_xattr_afs_volume_handler, &afs_xattr_yfs_handler, /* afs.yfs. prefix */ NULL }; 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