| blob | 44baf901238cacc3ebdb300d824b6a994c42927e |
1 ext4 crypto: partial update to namei.c for fname crypto
3 From: Michael Halcrow <mhalcrow@google.com>
5 Modifies dx_show_leaf and dx_probe to support fname encryption.
6 Filename encryption not yet enabled.
8 Signed-off-by: Uday Savagaonkar <savagaon@google.com>
9 Signed-off-by: Ildar Muslukhov <ildarm@google.com>
10 Signed-off-by: Michael Halcrow <mhalcrow@google.com>
11 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
12 ---
13 fs/ext4/namei.c | 109 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-------
14 1 file changed, 101 insertions(+), 8 deletions(-)
16 diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
17 index f3234d4..8fcda60 100644
18 --- a/fs/ext4/namei.c
19 +++ b/fs/ext4/namei.c
20 @@ -588,8 +588,10 @@ struct stats
21 unsigned bcount;
22 };
24 -static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext4_dir_entry_2 *de,
25 - int size, int show_names)
26 +static struct stats dx_show_leaf(struct inode *dir,
27 + struct dx_hash_info *hinfo,
28 + struct ext4_dir_entry_2 *de,
29 + int size, int show_names)
30 {
31 unsigned names = 0, space = 0;
32 char *base = (char *) de;
33 @@ -602,12 +604,80 @@ static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext4_dir_ent
34 {
35 if (show_names)
36 {
37 +#ifdef CONFIG_EXT4_FS_ENCRYPTION
38 + int len;
39 + char *name;
40 + struct ext4_str fname_crypto_str
41 + = {.name = NULL, .len = 0};
42 + struct ext4_fname_crypto_ctx *ctx = NULL;
43 + int res;
44 +
45 + name = de->name;
46 + len = de->name_len;
47 + ctx = ext4_get_fname_crypto_ctx(dir,
48 + EXT4_NAME_LEN);
49 + if (IS_ERR(ctx)) {
50 + printk(KERN_WARNING "Error acquiring"
51 + " crypto ctxt--skipping crypto\n");
52 + ctx = NULL;
53 + }
54 + if (ctx == NULL) {
55 + /* Directory is not encrypted */
56 + ext4fs_dirhash(de->name,
57 + de->name_len, &h);
58 + printk("%*.s:(U)%x.%u ", len,
59 + name, h.hash,
60 + (unsigned) ((char *) de
61 + - base));
62 + } else {
63 + /* Directory is encrypted */
64 + res = ext4_fname_crypto_alloc_buffer(
65 + ctx, de->name_len,
66 + &fname_crypto_str);
67 + if (res < 0) {
68 + printk(KERN_WARNING "Error "
69 + "allocating crypto "
70 + "buffer--skipping "
71 + "crypto\n");
72 + ext4_put_fname_crypto_ctx(&ctx);
73 + ctx = NULL;
74 + }
75 + res = ext4_fname_disk_to_usr(ctx, de,
76 + &fname_crypto_str);
77 + if (res < 0) {
78 + printk(KERN_WARNING "Error "
79 + "converting filename "
80 + "from disk to usr"
81 + "\n");
82 + name = "??";
83 + len = 2;
84 + } else {
85 + name = fname_crypto_str.name;
86 + len = fname_crypto_str.len;
87 + }
88 + res = ext4_fname_disk_to_hash(ctx, de,
89 + &h);
90 + if (res < 0) {
91 + printk(KERN_WARNING "Error "
92 + "converting filename "
93 + "from disk to htree"
94 + "\n");
95 + h.hash = 0xDEADBEEF;
96 + }
97 + printk("%*.s:(E)%x.%u ", len, name,
98 + h.hash, (unsigned) ((char *) de
99 + - base));
100 + ext4_put_fname_crypto_ctx(&ctx);
101 + ext4_fname_crypto_free_buffer(
102 + &fname_crypto_str);
103 + }
104 +#else
105 int len = de->name_len;
106 char *name = de->name;
107 - while (len--) printk("%c", *name++);
108 ext4fs_dirhash(de->name, de->name_len, &h);
109 - printk(":%x.%u ", h.hash,
110 + printk("%*.s:%x.%u ", len, name, h.hash,
111 (unsigned) ((char *) de - base));
112 +#endif
113 }
114 space += EXT4_DIR_REC_LEN(de->name_len);
115 names++;
116 @@ -625,7 +695,6 @@ struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
117 unsigned count = dx_get_count(entries), names = 0, space = 0, i;
118 unsigned bcount = 0;
119 struct buffer_head *bh;
120 - int err;
121 printk("%i indexed blocks...\n", count);
122 for (i = 0; i < count; i++, entries++)
123 {
124 @@ -639,7 +708,8 @@ struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
125 continue;
126 stats = levels?
127 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):
128 - dx_show_leaf(hinfo, (struct ext4_dir_entry_2 *) bh->b_data, blocksize, 0);
129 + dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *)
130 + bh->b_data, blocksize, 0);
131 names += stats.names;
132 space += stats.space;
133 bcount += stats.bcount;
134 @@ -689,8 +759,28 @@ dx_probe(const struct qstr *d_name, struct inode *dir,
135 if (hinfo->hash_version <= DX_HASH_TEA)
136 hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
137 hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed;
138 +#ifdef CONFIG_EXT4_FS_ENCRYPTION
139 + if (d_name) {
140 + struct ext4_fname_crypto_ctx *ctx = NULL;
141 + int res;
142 +
143 + /* Check if the directory is encrypted */
144 + ctx = ext4_get_fname_crypto_ctx(dir, EXT4_NAME_LEN);
145 + if (IS_ERR(ctx)) {
146 + ret_err = ERR_PTR(PTR_ERR(ctx));
147 + goto fail;
148 + }
149 + res = ext4_fname_usr_to_hash(ctx, d_name, hinfo);
150 + if (res < 0) {
151 + ret_err = ERR_PTR(res);
152 + goto fail;
153 + }
154 + ext4_put_fname_crypto_ctx(&ctx);
155 + }
156 +#else
157 if (d_name)
158 ext4fs_dirhash(d_name->name, d_name->len, hinfo);
159 +#endif
160 hash = hinfo->hash;
162 if (root->info.unused_flags & 1) {
163 @@ -775,6 +865,7 @@ fail:
164 brelse(frame->bh);
165 frame--;
166 }
167 +
168 if (ret_err == ERR_PTR(ERR_BAD_DX_DIR))
169 ext4_warning(dir->i_sb,
170 "Corrupt dir inode %lu, running e2fsck is "
171 @@ -1602,8 +1693,10 @@ static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
172 initialize_dirent_tail(t, blocksize);
173 }
175 - dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data1, blocksize, 1));
176 - dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data2, blocksize, 1));
177 + dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data1,
178 + blocksize, 1));
179 + dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data2,
180 + blocksize, 1));
182 /* Which block gets the new entry? */
183 if (hinfo->hash >= hash2) {