projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| ac27a0ec | 1 | /* |
| 617ba13b | 2 | * linux/fs/ext4/symlink.c |
| ac27a0ec DK |
3 | * |
| 4 | * Only fast symlinks left here - the rest is done by generic code. AV, 1999 | |
| 5 | * | |
| 6 | * Copyright (C) 1992, 1993, 1994, 1995 | |
| 7 | * Remy Card (card@masi.ibp.fr) | |
| 8 | * Laboratoire MASI - Institut Blaise Pascal | |
| 9 | * Universite Pierre et Marie Curie (Paris VI) | |
| 10 | * | |
| 11 | * from | |
| 12 | * | |
| 13 | * linux/fs/minix/symlink.c | |
| 14 | * | |
| 15 | * Copyright (C) 1991, 1992 Linus Torvalds | |
| 16 | * | |
| 617ba13b | 17 | * ext4 symlink handling code |
| ac27a0ec DK |
18 | */ |
| 19 | ||
| 20 | #include <linux/fs.h> | |
| ac27a0ec | 21 | #include <linux/namei.h> |
| 3dcf5451 | 22 | #include "ext4.h" |
| ac27a0ec DK |
23 | #include "xattr.h" |
| 24 | ||
| 6b255391 | 25 | static const char *ext4_encrypted_get_link(struct dentry *dentry, |
| fceef393 AV |
26 | struct inode *inode, |
| 27 | struct delayed_call *done) | |
| f348c252 TT |
28 | { |
| 29 | struct page *cpage = NULL; | |
| 30 | char *caddr, *paddr = NULL; | |
| a7550b30 JK |
31 | struct fscrypt_str cstr, pstr; |
| 32 | struct fscrypt_symlink_data *sd; | |
| f348c252 TT |
33 | loff_t size = min_t(loff_t, i_size_read(inode), PAGE_SIZE - 1); |
| 34 | int res; | |
| a7550b30 | 35 | u32 max_size = inode->i_sb->s_blocksize; |
| f348c252 | 36 | |
| 6b255391 AV |
37 | if (!dentry) |
| 38 | return ERR_PTR(-ECHILD); | |
| 39 | ||
| a7550b30 | 40 | res = fscrypt_get_encryption_info(inode); |
| b7236e21 TT |
41 | if (res) |
| 42 | return ERR_PTR(res); | |
| f348c252 TT |
43 | |
| 44 | if (ext4_inode_is_fast_symlink(inode)) { | |
| 9ec3a646 LT |
45 | caddr = (char *) EXT4_I(inode)->i_data; |
| 46 | max_size = sizeof(EXT4_I(inode)->i_data); | |
| f348c252 TT |
47 | } else { |
| 48 | cpage = read_mapping_page(inode->i_mapping, 0, NULL); | |
| b7236e21 | 49 | if (IS_ERR(cpage)) |
| 680baacb | 50 | return ERR_CAST(cpage); |
| 21fc61c7 | 51 | caddr = page_address(cpage); |
| f348c252 TT |
52 | caddr[size] = 0; |
| 53 | } | |
| 54 | ||
| 55 | /* Symlink is encrypted */ | |
| a7550b30 | 56 | sd = (struct fscrypt_symlink_data *)caddr; |
| f348c252 | 57 | cstr.name = sd->encrypted_path; |
| 5a1c7f47 | 58 | cstr.len = le16_to_cpu(sd->len); |
| a7550b30 | 59 | if ((cstr.len + sizeof(struct fscrypt_symlink_data) - 1) > max_size) { |
| f348c252 | 60 | /* Symlink data on the disk is corrupted */ |
| 6a797d27 | 61 | res = -EFSCORRUPTED; |
| f348c252 TT |
62 | goto errout; |
| 63 | } | |
| a7550b30 JK |
64 | |
| 65 | res = fscrypt_fname_alloc_buffer(inode, cstr.len, &pstr); | |
| 66 | if (res) | |
| f348c252 | 67 | goto errout; |
| a7550b30 JK |
68 | |
| 69 | res = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr); | |
| f348c252 TT |
70 | if (res < 0) |
| 71 | goto errout; | |
| a7550b30 JK |
72 | |
| 73 | paddr = pstr.name; | |
| 74 | ||
| f348c252 | 75 | /* Null-terminate the name */ |
| a7550b30 | 76 | if (res <= pstr.len) |
| f348c252 | 77 | paddr[res] = '\0'; |
| 21fc61c7 | 78 | if (cpage) |
| 09cbfeaf | 79 | put_page(cpage); |
| fceef393 AV |
80 | set_delayed_call(done, kfree_link, paddr); |
| 81 | return paddr; | |
| f348c252 | 82 | errout: |
| 21fc61c7 | 83 | if (cpage) |
| 09cbfeaf | 84 | put_page(cpage); |
| f348c252 TT |
85 | kfree(paddr); |
| 86 | return ERR_PTR(res); | |
| 87 | } | |
| 88 | ||
| a7a67e8a AV |
89 | const struct inode_operations ext4_encrypted_symlink_inode_operations = { |
| 90 | .readlink = generic_readlink, | |
| 6b255391 | 91 | .get_link = ext4_encrypted_get_link, |
| a7a67e8a AV |
92 | .setattr = ext4_setattr, |
| 93 | .setxattr = generic_setxattr, | |
| 94 | .getxattr = generic_getxattr, | |
| 95 | .listxattr = ext4_listxattr, | |
| 96 | .removexattr = generic_removexattr, | |
| 97 | }; | |
| f348c252 | 98 | |
| 754661f1 | 99 | const struct inode_operations ext4_symlink_inode_operations = { |
| ac27a0ec | 100 | .readlink = generic_readlink, |
| 6b255391 | 101 | .get_link = page_get_link, |
| 256a4535 | 102 | .setattr = ext4_setattr, |
| ac27a0ec DK |
103 | .setxattr = generic_setxattr, |
| 104 | .getxattr = generic_getxattr, | |
| 617ba13b | 105 | .listxattr = ext4_listxattr, |
| ac27a0ec | 106 | .removexattr = generic_removexattr, |
| ac27a0ec DK |
107 | }; |
| 108 | ||
| 754661f1 | 109 | const struct inode_operations ext4_fast_symlink_inode_operations = { |
| ac27a0ec | 110 | .readlink = generic_readlink, |
| 6b255391 | 111 | .get_link = simple_get_link, |
| 256a4535 | 112 | .setattr = ext4_setattr, |
| ac27a0ec DK |
113 | .setxattr = generic_setxattr, |
| 114 | .getxattr = generic_getxattr, | |
| 617ba13b | 115 | .listxattr = ext4_listxattr, |
| ac27a0ec | 116 | .removexattr = generic_removexattr, |
| ac27a0ec | 117 | }; |