1 // SPDX-License-Identifier: GPL-2.0
4 * Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved.
6 * Directory handling functions for NTFS-based filesystems.
11 #include <linux/nls.h>
17 /* Convert little endian UTF-16 to NLS string. */
18 int ntfs_utf16_to_nls(struct ntfs_sb_info *sbi, const struct le_str *uni,
21 int ret, uni_len, warn;
24 struct nls_table *nls = sbi->options->nls;
26 static_assert(sizeof(wchar_t) == sizeof(__le16));
30 ret = utf16s_to_utf8s((wchar_t *)uni->name, uni->len,
31 UTF16_LITTLE_ENDIAN, buf, buf_len);
46 if (buf_len < NLS_MAX_CHARSET_SIZE) {
48 "filename was truncated while converting.");
52 ec = le16_to_cpu(*ip++);
53 charlen = nls->uni2char(ec, op, buf_len);
67 hex_byte_pack(&dump[0], ec >> 8);
68 hex_byte_pack(&dump[2], ec);
71 ntfs_err(sbi->sb, "failed to convert \"%s\" to %s", dump,
80 #define PLANE_SIZE 0x00010000
82 #define SURROGATE_PAIR 0x0000d800
83 #define SURROGATE_LOW 0x00000400
84 #define SURROGATE_BITS 0x000003ff
88 * put_utf16 - Modified version of put_utf16 from fs/nls/nls_base.c
90 * Function is sparse warnings free.
92 static inline void put_utf16(wchar_t *s, unsigned int c,
93 enum utf16_endian endian)
95 static_assert(sizeof(wchar_t) == sizeof(__le16));
96 static_assert(sizeof(wchar_t) == sizeof(__be16));
102 case UTF16_LITTLE_ENDIAN:
103 *(__le16 *)s = __cpu_to_le16(c);
105 case UTF16_BIG_ENDIAN:
106 *(__be16 *)s = __cpu_to_be16(c);
114 * Modified version of 'utf8s_to_utf16s' allows to
115 * detect -ENAMETOOLONG without writing out of expected maximum.
117 static int _utf8s_to_utf16s(const u8 *s, int inlen, enum utf16_endian endian,
118 wchar_t *pwcs, int maxout)
125 while (inlen > 0 && *s) {
127 size = utf8_to_utf32(s, inlen, &u);
133 if (u >= PLANE_SIZE) {
135 return -ENAMETOOLONG;
140 ((u >> 10) & SURROGATE_BITS),
143 SURROGATE_PAIR | SURROGATE_LOW |
144 (u & SURROGATE_BITS),
149 return -ENAMETOOLONG;
151 put_utf16(op++, u, endian);
156 return -ENAMETOOLONG;
158 put_utf16(op++, *s++, endian);
167 * ntfs_nls_to_utf16 - Convert input string to UTF-16.
169 * @name_len: Input name length.
170 * @uni: Destination memory.
171 * @max_ulen: Destination memory.
172 * @endian: Endian of target UTF-16 string.
174 * This function is called:
175 * - to create NTFS name
176 * - to create symlink
178 * Return: UTF-16 string length or error (if negative).
180 int ntfs_nls_to_utf16(struct ntfs_sb_info *sbi, const u8 *name, u32 name_len,
181 struct cpu_str *uni, u32 max_ulen,
182 enum utf16_endian endian)
186 struct nls_table *nls = sbi->options->nls;
187 u16 *uname = uni->name;
189 static_assert(sizeof(wchar_t) == sizeof(u16));
193 ret = _utf8s_to_utf16s(name, name_len, endian, uname, max_ulen);
198 for (ret = 0, end = name + name_len; name < end; ret++, name += slen) {
200 return -ENAMETOOLONG;
202 slen = nls->char2uni(name, end - name, uname + ret);
210 if (endian == UTF16_LITTLE_ENDIAN) {
214 __cpu_to_le16s(uname);
219 if (endian == UTF16_BIG_ENDIAN) {
223 __cpu_to_be16s(uname);
234 * dir_search_u - Helper function.
236 struct inode *dir_search_u(struct inode *dir, const struct cpu_str *uni,
237 struct ntfs_fnd *fnd)
240 struct super_block *sb = dir->i_sb;
241 struct ntfs_sb_info *sbi = sb->s_fs_info;
242 struct ntfs_inode *ni = ntfs_i(dir);
245 struct inode *inode = NULL;
246 struct ntfs_fnd *fnd_a = NULL;
257 err = indx_find(&ni->dir, ni, NULL, uni, 0, sbi, &diff, &e, fnd);
267 inode = ntfs_iget5(sb, &e->ref, uni);
268 if (!IS_ERR(inode) && is_bad_inode(inode)) {
275 return err == -ENOENT ? NULL : err ? ERR_PTR(err) : inode;
278 static inline int ntfs_filldir(struct ntfs_sb_info *sbi, struct ntfs_inode *ni,
279 const struct NTFS_DE *e, u8 *name,
280 struct dir_context *ctx)
282 const struct ATTR_FILE_NAME *fname;
287 fname = Add2Ptr(e, sizeof(struct NTFS_DE));
289 if (fname->type == FILE_NAME_DOS)
292 if (!mi_is_ref(&ni->mi, &fname->home))
295 ino = ino_get(&e->ref);
297 if (ino == MFT_REC_ROOT)
300 /* Skip meta files. Unless option to show metafiles is set. */
301 if (!sbi->options->showmeta && ntfs_is_meta_file(sbi, ino))
304 if (sbi->options->nohidden && (fname->dup.fa & FILE_ATTRIBUTE_HIDDEN))
307 name_len = ntfs_utf16_to_nls(sbi, (struct le_str *)&fname->name_len,
310 ntfs_warn(sbi->sb, "failed to convert name for inode %lx.",
315 dt_type = (fname->dup.fa & FILE_ATTRIBUTE_DIRECTORY) ? DT_DIR : DT_REG;
317 return !dir_emit(ctx, (s8 *)name, name_len, ino, dt_type);
321 * ntfs_read_hdr - Helper function for ntfs_readdir().
323 static int ntfs_read_hdr(struct ntfs_sb_info *sbi, struct ntfs_inode *ni,
324 const struct INDEX_HDR *hdr, u64 vbo, u64 pos,
325 u8 *name, struct dir_context *ctx)
328 const struct NTFS_DE *e;
330 u32 end = le32_to_cpu(hdr->used);
331 u32 off = le32_to_cpu(hdr->de_off);
333 for (;; off += e_size) {
334 if (off + sizeof(struct NTFS_DE) > end)
337 e = Add2Ptr(hdr, off);
338 e_size = le16_to_cpu(e->size);
339 if (e_size < sizeof(struct NTFS_DE) || off + e_size > end)
345 /* Skip already enumerated. */
349 if (le16_to_cpu(e->key_size) < SIZEOF_ATTRIBUTE_FILENAME)
352 ctx->pos = vbo + off;
354 /* Submit the name to the filldir callback. */
355 err = ntfs_filldir(sbi, ni, e, name, ctx);
362 * ntfs_readdir - file_operations::iterate_shared
364 * Use non sorted enumeration.
365 * We have an example of broken volume where sorted enumeration
366 * counts each name twice.
368 static int ntfs_readdir(struct file *file, struct dir_context *ctx)
370 const struct INDEX_ROOT *root;
375 struct inode *dir = file_inode(file);
376 struct ntfs_inode *ni = ntfs_i(dir);
377 struct super_block *sb = dir->i_sb;
378 struct ntfs_sb_info *sbi = sb->s_fs_info;
379 loff_t i_size = i_size_read(dir);
382 struct indx_node *node = NULL;
383 u8 index_bits = ni->dir.index_bits;
385 /* Name is a buffer of PATH_MAX length. */
386 static_assert(NTFS_NAME_LEN * 4 < PATH_MAX);
388 eod = i_size + sbi->record_size;
393 if (!dir_emit_dots(file, ctx))
396 /* Allocate PATH_MAX bytes. */
401 if (!ni->mi_loaded && ni->attr_list.size) {
403 * Directory inode is locked for read.
404 * Load all subrecords to avoid 'write' access to 'ni' during
408 if (!ni->mi_loaded && ni->attr_list.size) {
409 err = ni_load_all_mi(ni);
411 ni->mi_loaded = true;
418 root = indx_get_root(&ni->dir, ni, NULL, NULL);
424 if (pos >= sbi->record_size) {
425 bit = (pos - sbi->record_size) >> index_bits;
427 err = ntfs_read_hdr(sbi, ni, &root->ihdr, 0, pos, name, ctx);
439 vbo = (u64)bit << index_bits;
445 err = indx_used_bit(&ni->dir, ni, &bit);
449 if (bit == MINUS_ONE_T) {
454 vbo = (u64)bit << index_bits;
456 ntfs_inode_err(dir, "Looks like your dir is corrupt");
461 err = indx_read(&ni->dir, ni, bit << ni->dir.idx2vbn_bits,
466 err = ntfs_read_hdr(sbi, ni, &node->index->ihdr,
467 vbo + sbi->record_size, pos, name, ctx);
479 if (err == -ENOENT) {
487 static int ntfs_dir_count(struct inode *dir, bool *is_empty, size_t *dirs,
491 struct ntfs_inode *ni = ntfs_i(dir);
492 struct NTFS_DE *e = NULL;
493 struct INDEX_ROOT *root;
494 struct INDEX_HDR *hdr;
495 const struct ATTR_FILE_NAME *fname;
496 u32 e_size, off, end;
498 size_t drs = 0, fles = 0, bit = 0;
499 loff_t i_size = ni->vfs_inode.i_size;
500 struct indx_node *node = NULL;
501 u8 index_bits = ni->dir.index_bits;
506 root = indx_get_root(&ni->dir, ni, NULL, NULL);
513 end = le32_to_cpu(hdr->used);
514 off = le32_to_cpu(hdr->de_off);
516 for (; off + sizeof(struct NTFS_DE) <= end; off += e_size) {
517 e = Add2Ptr(hdr, off);
518 e_size = le16_to_cpu(e->size);
519 if (e_size < sizeof(struct NTFS_DE) ||
526 fname = de_get_fname(e);
530 if (fname->type == FILE_NAME_DOS)
539 if (fname->dup.fa & FILE_ATTRIBUTE_DIRECTORY)
548 err = indx_used_bit(&ni->dir, ni, &bit);
552 if (bit == MINUS_ONE_T)
555 vbo = (u64)bit << index_bits;
559 err = indx_read(&ni->dir, ni, bit << ni->dir.idx2vbn_bits,
564 hdr = &node->index->ihdr;
566 vbo = (u64)bit << ni->dir.idx2vbn_bits;
579 bool dir_is_empty(struct inode *dir)
581 bool is_empty = false;
583 ntfs_dir_count(dir, &is_empty, NULL, NULL);
589 const struct file_operations ntfs_dir_operations = {
590 .llseek = generic_file_llseek,
591 .read = generic_read_dir,
592 .iterate_shared = ntfs_readdir,
593 .fsync = generic_file_fsync,
594 .open = ntfs_file_open,