Kyle Swenson | 8d8f654 | 2021-03-15 11:02:55 -0600 | [diff] [blame^] | 1 | /* |
| 2 | * fs/cifs/link.c |
| 3 | * |
| 4 | * Copyright (C) International Business Machines Corp., 2002,2008 |
| 5 | * Author(s): Steve French (sfrench@us.ibm.com) |
| 6 | * |
| 7 | * This library is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU Lesser General Public License as published |
| 9 | * by the Free Software Foundation; either version 2.1 of the License, or |
| 10 | * (at your option) any later version. |
| 11 | * |
| 12 | * This library is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
| 15 | * the GNU Lesser General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU Lesser General Public License |
| 18 | * along with this library; if not, write to the Free Software |
| 19 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 20 | */ |
| 21 | #include <linux/fs.h> |
| 22 | #include <linux/stat.h> |
| 23 | #include <linux/slab.h> |
| 24 | #include <linux/namei.h> |
| 25 | #include "cifsfs.h" |
| 26 | #include "cifspdu.h" |
| 27 | #include "cifsglob.h" |
| 28 | #include "cifsproto.h" |
| 29 | #include "cifs_debug.h" |
| 30 | #include "cifs_fs_sb.h" |
| 31 | #include "cifs_unicode.h" |
| 32 | #ifdef CONFIG_CIFS_SMB2 |
| 33 | #include "smb2proto.h" |
| 34 | #endif |
| 35 | |
| 36 | /* |
| 37 | * M-F Symlink Functions - Begin |
| 38 | */ |
| 39 | |
| 40 | #define CIFS_MF_SYMLINK_LEN_OFFSET (4+1) |
| 41 | #define CIFS_MF_SYMLINK_MD5_OFFSET (CIFS_MF_SYMLINK_LEN_OFFSET+(4+1)) |
| 42 | #define CIFS_MF_SYMLINK_LINK_OFFSET (CIFS_MF_SYMLINK_MD5_OFFSET+(32+1)) |
| 43 | #define CIFS_MF_SYMLINK_LINK_MAXLEN (1024) |
| 44 | #define CIFS_MF_SYMLINK_FILE_SIZE \ |
| 45 | (CIFS_MF_SYMLINK_LINK_OFFSET + CIFS_MF_SYMLINK_LINK_MAXLEN) |
| 46 | |
| 47 | #define CIFS_MF_SYMLINK_LEN_FORMAT "XSym\n%04u\n" |
| 48 | #define CIFS_MF_SYMLINK_MD5_FORMAT \ |
| 49 | "%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n" |
| 50 | #define CIFS_MF_SYMLINK_MD5_ARGS(md5_hash) \ |
| 51 | md5_hash[0], md5_hash[1], md5_hash[2], md5_hash[3], \ |
| 52 | md5_hash[4], md5_hash[5], md5_hash[6], md5_hash[7], \ |
| 53 | md5_hash[8], md5_hash[9], md5_hash[10], md5_hash[11],\ |
| 54 | md5_hash[12], md5_hash[13], md5_hash[14], md5_hash[15] |
| 55 | |
| 56 | static int |
| 57 | symlink_hash(unsigned int link_len, const char *link_str, u8 *md5_hash) |
| 58 | { |
| 59 | int rc; |
| 60 | unsigned int size; |
| 61 | struct crypto_shash *md5; |
| 62 | struct sdesc *sdescmd5; |
| 63 | |
| 64 | md5 = crypto_alloc_shash("md5", 0, 0); |
| 65 | if (IS_ERR(md5)) { |
| 66 | rc = PTR_ERR(md5); |
| 67 | cifs_dbg(VFS, "%s: Crypto md5 allocation error %d\n", |
| 68 | __func__, rc); |
| 69 | return rc; |
| 70 | } |
| 71 | size = sizeof(struct shash_desc) + crypto_shash_descsize(md5); |
| 72 | sdescmd5 = kmalloc(size, GFP_KERNEL); |
| 73 | if (!sdescmd5) { |
| 74 | rc = -ENOMEM; |
| 75 | goto symlink_hash_err; |
| 76 | } |
| 77 | sdescmd5->shash.tfm = md5; |
| 78 | sdescmd5->shash.flags = 0x0; |
| 79 | |
| 80 | rc = crypto_shash_init(&sdescmd5->shash); |
| 81 | if (rc) { |
| 82 | cifs_dbg(VFS, "%s: Could not init md5 shash\n", __func__); |
| 83 | goto symlink_hash_err; |
| 84 | } |
| 85 | rc = crypto_shash_update(&sdescmd5->shash, link_str, link_len); |
| 86 | if (rc) { |
| 87 | cifs_dbg(VFS, "%s: Could not update with link_str\n", __func__); |
| 88 | goto symlink_hash_err; |
| 89 | } |
| 90 | rc = crypto_shash_final(&sdescmd5->shash, md5_hash); |
| 91 | if (rc) |
| 92 | cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__); |
| 93 | |
| 94 | symlink_hash_err: |
| 95 | crypto_free_shash(md5); |
| 96 | kfree(sdescmd5); |
| 97 | |
| 98 | return rc; |
| 99 | } |
| 100 | |
| 101 | static int |
| 102 | parse_mf_symlink(const u8 *buf, unsigned int buf_len, unsigned int *_link_len, |
| 103 | char **_link_str) |
| 104 | { |
| 105 | int rc; |
| 106 | unsigned int link_len; |
| 107 | const char *md5_str1; |
| 108 | const char *link_str; |
| 109 | u8 md5_hash[16]; |
| 110 | char md5_str2[34]; |
| 111 | |
| 112 | if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE) |
| 113 | return -EINVAL; |
| 114 | |
| 115 | md5_str1 = (const char *)&buf[CIFS_MF_SYMLINK_MD5_OFFSET]; |
| 116 | link_str = (const char *)&buf[CIFS_MF_SYMLINK_LINK_OFFSET]; |
| 117 | |
| 118 | rc = sscanf(buf, CIFS_MF_SYMLINK_LEN_FORMAT, &link_len); |
| 119 | if (rc != 1) |
| 120 | return -EINVAL; |
| 121 | |
| 122 | rc = symlink_hash(link_len, link_str, md5_hash); |
| 123 | if (rc) { |
| 124 | cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc); |
| 125 | return rc; |
| 126 | } |
| 127 | |
| 128 | snprintf(md5_str2, sizeof(md5_str2), |
| 129 | CIFS_MF_SYMLINK_MD5_FORMAT, |
| 130 | CIFS_MF_SYMLINK_MD5_ARGS(md5_hash)); |
| 131 | |
| 132 | if (strncmp(md5_str1, md5_str2, 17) != 0) |
| 133 | return -EINVAL; |
| 134 | |
| 135 | if (_link_str) { |
| 136 | *_link_str = kstrndup(link_str, link_len, GFP_KERNEL); |
| 137 | if (!*_link_str) |
| 138 | return -ENOMEM; |
| 139 | } |
| 140 | |
| 141 | *_link_len = link_len; |
| 142 | return 0; |
| 143 | } |
| 144 | |
| 145 | static int |
| 146 | format_mf_symlink(u8 *buf, unsigned int buf_len, const char *link_str) |
| 147 | { |
| 148 | int rc; |
| 149 | unsigned int link_len; |
| 150 | unsigned int ofs; |
| 151 | u8 md5_hash[16]; |
| 152 | |
| 153 | if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE) |
| 154 | return -EINVAL; |
| 155 | |
| 156 | link_len = strlen(link_str); |
| 157 | |
| 158 | if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN) |
| 159 | return -ENAMETOOLONG; |
| 160 | |
| 161 | rc = symlink_hash(link_len, link_str, md5_hash); |
| 162 | if (rc) { |
| 163 | cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc); |
| 164 | return rc; |
| 165 | } |
| 166 | |
| 167 | snprintf(buf, buf_len, |
| 168 | CIFS_MF_SYMLINK_LEN_FORMAT CIFS_MF_SYMLINK_MD5_FORMAT, |
| 169 | link_len, |
| 170 | CIFS_MF_SYMLINK_MD5_ARGS(md5_hash)); |
| 171 | |
| 172 | ofs = CIFS_MF_SYMLINK_LINK_OFFSET; |
| 173 | memcpy(buf + ofs, link_str, link_len); |
| 174 | |
| 175 | ofs += link_len; |
| 176 | if (ofs < CIFS_MF_SYMLINK_FILE_SIZE) { |
| 177 | buf[ofs] = '\n'; |
| 178 | ofs++; |
| 179 | } |
| 180 | |
| 181 | while (ofs < CIFS_MF_SYMLINK_FILE_SIZE) { |
| 182 | buf[ofs] = ' '; |
| 183 | ofs++; |
| 184 | } |
| 185 | |
| 186 | return 0; |
| 187 | } |
| 188 | |
| 189 | bool |
| 190 | couldbe_mf_symlink(const struct cifs_fattr *fattr) |
| 191 | { |
| 192 | if (!S_ISREG(fattr->cf_mode)) |
| 193 | /* it's not a symlink */ |
| 194 | return false; |
| 195 | |
| 196 | if (fattr->cf_eof != CIFS_MF_SYMLINK_FILE_SIZE) |
| 197 | /* it's not a symlink */ |
| 198 | return false; |
| 199 | |
| 200 | return true; |
| 201 | } |
| 202 | |
| 203 | static int |
| 204 | create_mf_symlink(const unsigned int xid, struct cifs_tcon *tcon, |
| 205 | struct cifs_sb_info *cifs_sb, const char *fromName, |
| 206 | const char *toName) |
| 207 | { |
| 208 | int rc; |
| 209 | u8 *buf; |
| 210 | unsigned int bytes_written = 0; |
| 211 | |
| 212 | buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL); |
| 213 | if (!buf) |
| 214 | return -ENOMEM; |
| 215 | |
| 216 | rc = format_mf_symlink(buf, CIFS_MF_SYMLINK_FILE_SIZE, toName); |
| 217 | if (rc) |
| 218 | goto out; |
| 219 | |
| 220 | if (tcon->ses->server->ops->create_mf_symlink) |
| 221 | rc = tcon->ses->server->ops->create_mf_symlink(xid, tcon, |
| 222 | cifs_sb, fromName, buf, &bytes_written); |
| 223 | else |
| 224 | rc = -EOPNOTSUPP; |
| 225 | |
| 226 | if (rc) |
| 227 | goto out; |
| 228 | |
| 229 | if (bytes_written != CIFS_MF_SYMLINK_FILE_SIZE) |
| 230 | rc = -EIO; |
| 231 | out: |
| 232 | kfree(buf); |
| 233 | return rc; |
| 234 | } |
| 235 | |
| 236 | static int |
| 237 | query_mf_symlink(const unsigned int xid, struct cifs_tcon *tcon, |
| 238 | struct cifs_sb_info *cifs_sb, const unsigned char *path, |
| 239 | char **symlinkinfo) |
| 240 | { |
| 241 | int rc; |
| 242 | u8 *buf = NULL; |
| 243 | unsigned int link_len = 0; |
| 244 | unsigned int bytes_read = 0; |
| 245 | |
| 246 | buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL); |
| 247 | if (!buf) |
| 248 | return -ENOMEM; |
| 249 | |
| 250 | if (tcon->ses->server->ops->query_mf_symlink) |
| 251 | rc = tcon->ses->server->ops->query_mf_symlink(xid, tcon, |
| 252 | cifs_sb, path, buf, &bytes_read); |
| 253 | else |
| 254 | rc = -ENOSYS; |
| 255 | |
| 256 | if (rc) |
| 257 | goto out; |
| 258 | |
| 259 | if (bytes_read == 0) { /* not a symlink */ |
| 260 | rc = -EINVAL; |
| 261 | goto out; |
| 262 | } |
| 263 | |
| 264 | rc = parse_mf_symlink(buf, bytes_read, &link_len, symlinkinfo); |
| 265 | out: |
| 266 | kfree(buf); |
| 267 | return rc; |
| 268 | } |
| 269 | |
| 270 | int |
| 271 | check_mf_symlink(unsigned int xid, struct cifs_tcon *tcon, |
| 272 | struct cifs_sb_info *cifs_sb, struct cifs_fattr *fattr, |
| 273 | const unsigned char *path) |
| 274 | { |
| 275 | int rc; |
| 276 | u8 *buf = NULL; |
| 277 | unsigned int link_len = 0; |
| 278 | unsigned int bytes_read = 0; |
| 279 | |
| 280 | if (!couldbe_mf_symlink(fattr)) |
| 281 | /* it's not a symlink */ |
| 282 | return 0; |
| 283 | |
| 284 | buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL); |
| 285 | if (!buf) |
| 286 | return -ENOMEM; |
| 287 | |
| 288 | if (tcon->ses->server->ops->query_mf_symlink) |
| 289 | rc = tcon->ses->server->ops->query_mf_symlink(xid, tcon, |
| 290 | cifs_sb, path, buf, &bytes_read); |
| 291 | else |
| 292 | rc = -ENOSYS; |
| 293 | |
| 294 | if (rc) |
| 295 | goto out; |
| 296 | |
| 297 | if (bytes_read == 0) /* not a symlink */ |
| 298 | goto out; |
| 299 | |
| 300 | rc = parse_mf_symlink(buf, bytes_read, &link_len, NULL); |
| 301 | if (rc == -EINVAL) { |
| 302 | /* it's not a symlink */ |
| 303 | rc = 0; |
| 304 | goto out; |
| 305 | } |
| 306 | |
| 307 | if (rc != 0) |
| 308 | goto out; |
| 309 | |
| 310 | /* it is a symlink */ |
| 311 | fattr->cf_eof = link_len; |
| 312 | fattr->cf_mode &= ~S_IFMT; |
| 313 | fattr->cf_mode |= S_IFLNK | S_IRWXU | S_IRWXG | S_IRWXO; |
| 314 | fattr->cf_dtype = DT_LNK; |
| 315 | out: |
| 316 | kfree(buf); |
| 317 | return rc; |
| 318 | } |
| 319 | |
| 320 | /* |
| 321 | * SMB 1.0 Protocol specific functions |
| 322 | */ |
| 323 | |
| 324 | int |
| 325 | cifs_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon, |
| 326 | struct cifs_sb_info *cifs_sb, const unsigned char *path, |
| 327 | char *pbuf, unsigned int *pbytes_read) |
| 328 | { |
| 329 | int rc; |
| 330 | int oplock = 0; |
| 331 | struct cifs_fid fid; |
| 332 | struct cifs_open_parms oparms; |
| 333 | struct cifs_io_parms io_parms; |
| 334 | int buf_type = CIFS_NO_BUFFER; |
| 335 | FILE_ALL_INFO file_info; |
| 336 | |
| 337 | oparms.tcon = tcon; |
| 338 | oparms.cifs_sb = cifs_sb; |
| 339 | oparms.desired_access = GENERIC_READ; |
| 340 | oparms.create_options = CREATE_NOT_DIR; |
| 341 | oparms.disposition = FILE_OPEN; |
| 342 | oparms.path = path; |
| 343 | oparms.fid = &fid; |
| 344 | oparms.reconnect = false; |
| 345 | |
| 346 | rc = CIFS_open(xid, &oparms, &oplock, &file_info); |
| 347 | if (rc) |
| 348 | return rc; |
| 349 | |
| 350 | if (file_info.EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) { |
| 351 | rc = -ENOENT; |
| 352 | /* it's not a symlink */ |
| 353 | goto out; |
| 354 | } |
| 355 | |
| 356 | io_parms.netfid = fid.netfid; |
| 357 | io_parms.pid = current->tgid; |
| 358 | io_parms.tcon = tcon; |
| 359 | io_parms.offset = 0; |
| 360 | io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE; |
| 361 | |
| 362 | rc = CIFSSMBRead(xid, &io_parms, pbytes_read, &pbuf, &buf_type); |
| 363 | out: |
| 364 | CIFSSMBClose(xid, tcon, fid.netfid); |
| 365 | return rc; |
| 366 | } |
| 367 | |
| 368 | int |
| 369 | cifs_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon, |
| 370 | struct cifs_sb_info *cifs_sb, const unsigned char *path, |
| 371 | char *pbuf, unsigned int *pbytes_written) |
| 372 | { |
| 373 | int rc; |
| 374 | int oplock = 0; |
| 375 | struct cifs_fid fid; |
| 376 | struct cifs_open_parms oparms; |
| 377 | struct cifs_io_parms io_parms; |
| 378 | int create_options = CREATE_NOT_DIR; |
| 379 | |
| 380 | if (backup_cred(cifs_sb)) |
| 381 | create_options |= CREATE_OPEN_BACKUP_INTENT; |
| 382 | |
| 383 | oparms.tcon = tcon; |
| 384 | oparms.cifs_sb = cifs_sb; |
| 385 | oparms.desired_access = GENERIC_WRITE; |
| 386 | oparms.create_options = create_options; |
| 387 | oparms.disposition = FILE_CREATE; |
| 388 | oparms.path = path; |
| 389 | oparms.fid = &fid; |
| 390 | oparms.reconnect = false; |
| 391 | |
| 392 | rc = CIFS_open(xid, &oparms, &oplock, NULL); |
| 393 | if (rc) |
| 394 | return rc; |
| 395 | |
| 396 | io_parms.netfid = fid.netfid; |
| 397 | io_parms.pid = current->tgid; |
| 398 | io_parms.tcon = tcon; |
| 399 | io_parms.offset = 0; |
| 400 | io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE; |
| 401 | |
| 402 | rc = CIFSSMBWrite(xid, &io_parms, pbytes_written, pbuf, NULL, 0); |
| 403 | CIFSSMBClose(xid, tcon, fid.netfid); |
| 404 | return rc; |
| 405 | } |
| 406 | |
| 407 | /* |
| 408 | * SMB 2.1/SMB3 Protocol specific functions |
| 409 | */ |
| 410 | #ifdef CONFIG_CIFS_SMB2 |
| 411 | int |
| 412 | smb3_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon, |
| 413 | struct cifs_sb_info *cifs_sb, const unsigned char *path, |
| 414 | char *pbuf, unsigned int *pbytes_read) |
| 415 | { |
| 416 | int rc; |
| 417 | struct cifs_fid fid; |
| 418 | struct cifs_open_parms oparms; |
| 419 | struct cifs_io_parms io_parms; |
| 420 | int buf_type = CIFS_NO_BUFFER; |
| 421 | __le16 *utf16_path; |
| 422 | __u8 oplock = SMB2_OPLOCK_LEVEL_II; |
| 423 | struct smb2_file_all_info *pfile_info = NULL; |
| 424 | |
| 425 | oparms.tcon = tcon; |
| 426 | oparms.cifs_sb = cifs_sb; |
| 427 | oparms.desired_access = GENERIC_READ; |
| 428 | oparms.create_options = CREATE_NOT_DIR; |
| 429 | if (backup_cred(cifs_sb)) |
| 430 | oparms.create_options |= CREATE_OPEN_BACKUP_INTENT; |
| 431 | oparms.disposition = FILE_OPEN; |
| 432 | oparms.fid = &fid; |
| 433 | oparms.reconnect = false; |
| 434 | |
| 435 | utf16_path = cifs_convert_path_to_utf16(path, cifs_sb); |
| 436 | if (utf16_path == NULL) |
| 437 | return -ENOMEM; |
| 438 | |
| 439 | pfile_info = kzalloc(sizeof(struct smb2_file_all_info) + PATH_MAX * 2, |
| 440 | GFP_KERNEL); |
| 441 | |
| 442 | if (pfile_info == NULL) { |
| 443 | kfree(utf16_path); |
| 444 | return -ENOMEM; |
| 445 | } |
| 446 | |
| 447 | rc = SMB2_open(xid, &oparms, utf16_path, &oplock, pfile_info, NULL); |
| 448 | if (rc) |
| 449 | goto qmf_out_open_fail; |
| 450 | |
| 451 | if (pfile_info->EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) { |
| 452 | /* it's not a symlink */ |
| 453 | rc = -ENOENT; /* Is there a better rc to return? */ |
| 454 | goto qmf_out; |
| 455 | } |
| 456 | |
| 457 | io_parms.netfid = fid.netfid; |
| 458 | io_parms.pid = current->tgid; |
| 459 | io_parms.tcon = tcon; |
| 460 | io_parms.offset = 0; |
| 461 | io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE; |
| 462 | io_parms.persistent_fid = fid.persistent_fid; |
| 463 | io_parms.volatile_fid = fid.volatile_fid; |
| 464 | rc = SMB2_read(xid, &io_parms, pbytes_read, &pbuf, &buf_type); |
| 465 | qmf_out: |
| 466 | SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid); |
| 467 | qmf_out_open_fail: |
| 468 | kfree(utf16_path); |
| 469 | kfree(pfile_info); |
| 470 | return rc; |
| 471 | } |
| 472 | |
| 473 | int |
| 474 | smb3_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon, |
| 475 | struct cifs_sb_info *cifs_sb, const unsigned char *path, |
| 476 | char *pbuf, unsigned int *pbytes_written) |
| 477 | { |
| 478 | int rc; |
| 479 | struct cifs_fid fid; |
| 480 | struct cifs_open_parms oparms; |
| 481 | struct cifs_io_parms io_parms; |
| 482 | int create_options = CREATE_NOT_DIR; |
| 483 | __le16 *utf16_path; |
| 484 | __u8 oplock = SMB2_OPLOCK_LEVEL_EXCLUSIVE; |
| 485 | struct kvec iov[2]; |
| 486 | |
| 487 | if (backup_cred(cifs_sb)) |
| 488 | create_options |= CREATE_OPEN_BACKUP_INTENT; |
| 489 | |
| 490 | cifs_dbg(FYI, "%s: path: %s\n", __func__, path); |
| 491 | |
| 492 | utf16_path = cifs_convert_path_to_utf16(path, cifs_sb); |
| 493 | if (!utf16_path) |
| 494 | return -ENOMEM; |
| 495 | |
| 496 | oparms.tcon = tcon; |
| 497 | oparms.cifs_sb = cifs_sb; |
| 498 | oparms.desired_access = GENERIC_WRITE; |
| 499 | oparms.create_options = create_options; |
| 500 | oparms.disposition = FILE_CREATE; |
| 501 | oparms.fid = &fid; |
| 502 | oparms.reconnect = false; |
| 503 | |
| 504 | rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL, NULL); |
| 505 | if (rc) { |
| 506 | kfree(utf16_path); |
| 507 | return rc; |
| 508 | } |
| 509 | |
| 510 | io_parms.netfid = fid.netfid; |
| 511 | io_parms.pid = current->tgid; |
| 512 | io_parms.tcon = tcon; |
| 513 | io_parms.offset = 0; |
| 514 | io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE; |
| 515 | io_parms.persistent_fid = fid.persistent_fid; |
| 516 | io_parms.volatile_fid = fid.volatile_fid; |
| 517 | |
| 518 | /* iov[0] is reserved for smb header */ |
| 519 | iov[1].iov_base = pbuf; |
| 520 | iov[1].iov_len = CIFS_MF_SYMLINK_FILE_SIZE; |
| 521 | |
| 522 | rc = SMB2_write(xid, &io_parms, pbytes_written, iov, 1); |
| 523 | |
| 524 | /* Make sure we wrote all of the symlink data */ |
| 525 | if ((rc == 0) && (*pbytes_written != CIFS_MF_SYMLINK_FILE_SIZE)) |
| 526 | rc = -EIO; |
| 527 | |
| 528 | SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid); |
| 529 | |
| 530 | kfree(utf16_path); |
| 531 | return rc; |
| 532 | } |
| 533 | #endif /* CONFIG_CIFS_SMB2 */ |
| 534 | |
| 535 | /* |
| 536 | * M-F Symlink Functions - End |
| 537 | */ |
| 538 | |
| 539 | int |
| 540 | cifs_hardlink(struct dentry *old_file, struct inode *inode, |
| 541 | struct dentry *direntry) |
| 542 | { |
| 543 | int rc = -EACCES; |
| 544 | unsigned int xid; |
| 545 | char *from_name = NULL; |
| 546 | char *to_name = NULL; |
| 547 | struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb); |
| 548 | struct tcon_link *tlink; |
| 549 | struct cifs_tcon *tcon; |
| 550 | struct TCP_Server_Info *server; |
| 551 | struct cifsInodeInfo *cifsInode; |
| 552 | |
| 553 | tlink = cifs_sb_tlink(cifs_sb); |
| 554 | if (IS_ERR(tlink)) |
| 555 | return PTR_ERR(tlink); |
| 556 | tcon = tlink_tcon(tlink); |
| 557 | |
| 558 | xid = get_xid(); |
| 559 | |
| 560 | from_name = build_path_from_dentry(old_file); |
| 561 | to_name = build_path_from_dentry(direntry); |
| 562 | if ((from_name == NULL) || (to_name == NULL)) { |
| 563 | rc = -ENOMEM; |
| 564 | goto cifs_hl_exit; |
| 565 | } |
| 566 | |
| 567 | if (tcon->unix_ext) |
| 568 | rc = CIFSUnixCreateHardLink(xid, tcon, from_name, to_name, |
| 569 | cifs_sb->local_nls, |
| 570 | cifs_remap(cifs_sb)); |
| 571 | else { |
| 572 | server = tcon->ses->server; |
| 573 | if (!server->ops->create_hardlink) { |
| 574 | rc = -ENOSYS; |
| 575 | goto cifs_hl_exit; |
| 576 | } |
| 577 | rc = server->ops->create_hardlink(xid, tcon, from_name, to_name, |
| 578 | cifs_sb); |
| 579 | if ((rc == -EIO) || (rc == -EINVAL)) |
| 580 | rc = -EOPNOTSUPP; |
| 581 | } |
| 582 | |
| 583 | d_drop(direntry); /* force new lookup from server of target */ |
| 584 | |
| 585 | /* |
| 586 | * if source file is cached (oplocked) revalidate will not go to server |
| 587 | * until the file is closed or oplock broken so update nlinks locally |
| 588 | */ |
| 589 | if (d_really_is_positive(old_file)) { |
| 590 | cifsInode = CIFS_I(d_inode(old_file)); |
| 591 | if (rc == 0) { |
| 592 | spin_lock(&d_inode(old_file)->i_lock); |
| 593 | inc_nlink(d_inode(old_file)); |
| 594 | spin_unlock(&d_inode(old_file)->i_lock); |
| 595 | |
| 596 | /* |
| 597 | * parent dir timestamps will update from srv within a |
| 598 | * second, would it really be worth it to set the parent |
| 599 | * dir cifs inode time to zero to force revalidate |
| 600 | * (faster) for it too? |
| 601 | */ |
| 602 | } |
| 603 | /* |
| 604 | * if not oplocked will force revalidate to get info on source |
| 605 | * file from srv. Note Samba server prior to 4.2 has bug - |
| 606 | * not updating src file ctime on hardlinks but Windows servers |
| 607 | * handle it properly |
| 608 | */ |
| 609 | cifsInode->time = 0; |
| 610 | |
| 611 | /* |
| 612 | * Will update parent dir timestamps from srv within a second. |
| 613 | * Would it really be worth it to set the parent dir (cifs |
| 614 | * inode) time field to zero to force revalidate on parent |
| 615 | * directory faster ie |
| 616 | * |
| 617 | * CIFS_I(inode)->time = 0; |
| 618 | */ |
| 619 | } |
| 620 | |
| 621 | cifs_hl_exit: |
| 622 | kfree(from_name); |
| 623 | kfree(to_name); |
| 624 | free_xid(xid); |
| 625 | cifs_put_tlink(tlink); |
| 626 | return rc; |
| 627 | } |
| 628 | |
| 629 | const char * |
| 630 | cifs_follow_link(struct dentry *direntry, void **cookie) |
| 631 | { |
| 632 | struct inode *inode = d_inode(direntry); |
| 633 | int rc = -ENOMEM; |
| 634 | unsigned int xid; |
| 635 | char *full_path = NULL; |
| 636 | char *target_path = NULL; |
| 637 | struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb); |
| 638 | struct tcon_link *tlink = NULL; |
| 639 | struct cifs_tcon *tcon; |
| 640 | struct TCP_Server_Info *server; |
| 641 | |
| 642 | xid = get_xid(); |
| 643 | |
| 644 | tlink = cifs_sb_tlink(cifs_sb); |
| 645 | if (IS_ERR(tlink)) { |
| 646 | free_xid(xid); |
| 647 | return ERR_CAST(tlink); |
| 648 | } |
| 649 | tcon = tlink_tcon(tlink); |
| 650 | server = tcon->ses->server; |
| 651 | |
| 652 | full_path = build_path_from_dentry(direntry); |
| 653 | if (!full_path) { |
| 654 | free_xid(xid); |
| 655 | cifs_put_tlink(tlink); |
| 656 | return ERR_PTR(-ENOMEM); |
| 657 | } |
| 658 | |
| 659 | cifs_dbg(FYI, "Full path: %s inode = 0x%p\n", full_path, inode); |
| 660 | |
| 661 | rc = -EACCES; |
| 662 | /* |
| 663 | * First try Minshall+French Symlinks, if configured |
| 664 | * and fallback to UNIX Extensions Symlinks. |
| 665 | */ |
| 666 | if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) |
| 667 | rc = query_mf_symlink(xid, tcon, cifs_sb, full_path, |
| 668 | &target_path); |
| 669 | |
| 670 | if (rc != 0 && server->ops->query_symlink) |
| 671 | rc = server->ops->query_symlink(xid, tcon, full_path, |
| 672 | &target_path, cifs_sb); |
| 673 | |
| 674 | kfree(full_path); |
| 675 | free_xid(xid); |
| 676 | cifs_put_tlink(tlink); |
| 677 | if (rc != 0) { |
| 678 | kfree(target_path); |
| 679 | return ERR_PTR(rc); |
| 680 | } |
| 681 | return *cookie = target_path; |
| 682 | } |
| 683 | |
| 684 | int |
| 685 | cifs_symlink(struct inode *inode, struct dentry *direntry, const char *symname) |
| 686 | { |
| 687 | int rc = -EOPNOTSUPP; |
| 688 | unsigned int xid; |
| 689 | struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb); |
| 690 | struct tcon_link *tlink; |
| 691 | struct cifs_tcon *pTcon; |
| 692 | char *full_path = NULL; |
| 693 | struct inode *newinode = NULL; |
| 694 | |
| 695 | xid = get_xid(); |
| 696 | |
| 697 | tlink = cifs_sb_tlink(cifs_sb); |
| 698 | if (IS_ERR(tlink)) { |
| 699 | rc = PTR_ERR(tlink); |
| 700 | goto symlink_exit; |
| 701 | } |
| 702 | pTcon = tlink_tcon(tlink); |
| 703 | |
| 704 | full_path = build_path_from_dentry(direntry); |
| 705 | if (full_path == NULL) { |
| 706 | rc = -ENOMEM; |
| 707 | goto symlink_exit; |
| 708 | } |
| 709 | |
| 710 | cifs_dbg(FYI, "Full path: %s\n", full_path); |
| 711 | cifs_dbg(FYI, "symname is %s\n", symname); |
| 712 | |
| 713 | /* BB what if DFS and this volume is on different share? BB */ |
| 714 | if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) |
| 715 | rc = create_mf_symlink(xid, pTcon, cifs_sb, full_path, symname); |
| 716 | else if (pTcon->unix_ext) |
| 717 | rc = CIFSUnixCreateSymLink(xid, pTcon, full_path, symname, |
| 718 | cifs_sb->local_nls, |
| 719 | cifs_remap(cifs_sb)); |
| 720 | /* else |
| 721 | rc = CIFSCreateReparseSymLink(xid, pTcon, fromName, toName, |
| 722 | cifs_sb_target->local_nls); */ |
| 723 | |
| 724 | if (rc == 0) { |
| 725 | if (pTcon->unix_ext) |
| 726 | rc = cifs_get_inode_info_unix(&newinode, full_path, |
| 727 | inode->i_sb, xid); |
| 728 | else |
| 729 | rc = cifs_get_inode_info(&newinode, full_path, NULL, |
| 730 | inode->i_sb, xid, NULL); |
| 731 | |
| 732 | if (rc != 0) { |
| 733 | cifs_dbg(FYI, "Create symlink ok, getinodeinfo fail rc = %d\n", |
| 734 | rc); |
| 735 | } else { |
| 736 | d_instantiate(direntry, newinode); |
| 737 | } |
| 738 | } |
| 739 | symlink_exit: |
| 740 | kfree(full_path); |
| 741 | cifs_put_tlink(tlink); |
| 742 | free_xid(xid); |
| 743 | return rc; |
| 744 | } |