1// SPDX-License-Identifier: GPL-2.0
 2#include "ubifs.h"
 3
 4static int ubifs_crypt_get_context(struct inode *inode, void *ctx, size_t len)
 5{
 6	return ubifs_xattr_get(inode, UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT,
 7			       ctx, len);
 8}
 9
10static int ubifs_crypt_set_context(struct inode *inode, const void *ctx,
11				   size_t len, void *fs_data)
12{
13	/*
14	 * Creating an encryption context is done unlocked since we
15	 * operate on a new inode which is not visible to other users
16	 * at this point. So, no need to check whether inode is locked.
17	 */
18	return ubifs_xattr_set(inode, UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT,
19			       ctx, len, 0, false);
20}
21
22static bool ubifs_crypt_empty_dir(struct inode *inode)
23{
24	return ubifs_check_dir_empty(inode) == 0;
25}
26
27int ubifs_encrypt(const struct inode *inode, struct ubifs_data_node *dn,
28		  unsigned int in_len, unsigned int *out_len, int block)
29{
30	struct ubifs_info *c = inode->i_sb->s_fs_info;
31	void *p = &dn->data;
32	unsigned int pad_len = round_up(in_len, UBIFS_CIPHER_BLOCK_SIZE);
33	int err;
34
35	ubifs_assert(c, pad_len <= *out_len);
36	dn->compr_size = cpu_to_le16(in_len);
37
38	/* pad to full block cipher length */
39	if (pad_len != in_len)
40		memset(p + in_len, 0, pad_len - in_len);
41
42	err = fscrypt_encrypt_block_inplace(inode, virt_to_page(p), pad_len,
43					    offset_in_page(p), block, GFP_NOFS);
44	if (err) {
45		ubifs_err(c, "fscrypt_encrypt_block_inplace() failed: %d", err);
46		return err;
47	}
48	*out_len = pad_len;
49
50	return 0;
51}
52
53int ubifs_decrypt(const struct inode *inode, struct ubifs_data_node *dn,
54		  unsigned int *out_len, int block)
55{
56	struct ubifs_info *c = inode->i_sb->s_fs_info;
57	int err;
58	unsigned int clen = le16_to_cpu(dn->compr_size);
59	unsigned int dlen = *out_len;
60
61	if (clen <= 0 || clen > UBIFS_BLOCK_SIZE || clen > dlen) {
62		ubifs_err(c, "bad compr_size: %i", clen);
63		return -EINVAL;
64	}
65
66	ubifs_assert(c, dlen <= UBIFS_BLOCK_SIZE);
67	err = fscrypt_decrypt_block_inplace(inode, virt_to_page(&dn->data),
68					    dlen, offset_in_page(&dn->data),
69					    block);
70	if (err) {
71		ubifs_err(c, "fscrypt_decrypt_block_inplace() failed: %d", err);
72		return err;
73	}
74	*out_len = clen;
75
76	return 0;
77}
78
79const struct fscrypt_operations ubifs_crypt_operations = {
80	.flags			= FS_CFLG_OWN_PAGES,
81	.key_prefix		= "ubifs:",
82	.get_context		= ubifs_crypt_get_context,
83	.set_context		= ubifs_crypt_set_context,
84	.empty_dir		= ubifs_crypt_empty_dir,
85	.max_namelen		= UBIFS_MAX_NLEN,
86};

 1// SPDX-License-Identifier: GPL-2.0
 2#include "ubifs.h"
 3
 4static int ubifs_crypt_get_context(struct inode *inode, void *ctx, size_t len)
 5{
 6	return ubifs_xattr_get(inode, UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT,
 7			       ctx, len);
 8}
 9
10static int ubifs_crypt_set_context(struct inode *inode, const void *ctx,
11				   size_t len, void *fs_data)
12{
13	/*
14	 * Creating an encryption context is done unlocked since we
15	 * operate on a new inode which is not visible to other users
16	 * at this point. So, no need to check whether inode is locked.
17	 */
18	return ubifs_xattr_set(inode, UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT,
19			       ctx, len, 0, false);
20}
21
22static bool ubifs_crypt_empty_dir(struct inode *inode)
23{
24	return ubifs_check_dir_empty(inode) == 0;
25}
26
27int ubifs_encrypt(const struct inode *inode, struct ubifs_data_node *dn,
28		  unsigned int in_len, unsigned int *out_len, int block)
29{
30	struct ubifs_info *c = inode->i_sb->s_fs_info;
31	void *p = &dn->data;
32	unsigned int pad_len = round_up(in_len, UBIFS_CIPHER_BLOCK_SIZE);
33	int err;
34
35	ubifs_assert(c, pad_len <= *out_len);
36	dn->compr_size = cpu_to_le16(in_len);
37
38	/* pad to full block cipher length */
39	if (pad_len != in_len)
40		memset(p + in_len, 0, pad_len - in_len);
41
42	err = fscrypt_encrypt_block_inplace(inode, virt_to_page(p), pad_len,
43					    offset_in_page(p), block, GFP_NOFS);
44	if (err) {
45		ubifs_err(c, "fscrypt_encrypt_block_inplace() failed: %d", err);
46		return err;
47	}
48	*out_len = pad_len;
49
50	return 0;
51}
52
53int ubifs_decrypt(const struct inode *inode, struct ubifs_data_node *dn,
54		  unsigned int *out_len, int block)
55{
56	struct ubifs_info *c = inode->i_sb->s_fs_info;
57	int err;
58	unsigned int clen = le16_to_cpu(dn->compr_size);
59	unsigned int dlen = *out_len;
60
61	if (clen <= 0 || clen > UBIFS_BLOCK_SIZE || clen > dlen) {
62		ubifs_err(c, "bad compr_size: %i", clen);
63		return -EINVAL;
64	}
65
66	ubifs_assert(c, dlen <= UBIFS_BLOCK_SIZE);
67	err = fscrypt_decrypt_block_inplace(inode, virt_to_page(&dn->data),
68					    dlen, offset_in_page(&dn->data),
69					    block);
70	if (err) {
71		ubifs_err(c, "fscrypt_decrypt_block_inplace() failed: %d", err);
72		return err;
73	}
74	*out_len = clen;
75
76	return 0;
77}
78
79const struct fscrypt_operations ubifs_crypt_operations = {
80	.flags			= FS_CFLG_OWN_PAGES,
81	.key_prefix		= "ubifs:",
82	.get_context		= ubifs_crypt_get_context,
83	.set_context		= ubifs_crypt_set_context,
84	.empty_dir		= ubifs_crypt_empty_dir,
85	.max_namelen		= UBIFS_MAX_NLEN,
86};