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
27/**
28 * ubifs_encrypt - Encrypt data.
29 * @inode: inode which refers to the data node
30 * @dn: data node to encrypt
31 * @in_len: length of data to be compressed
32 * @out_len: allocated memory size for the data area of @dn
33 * @block: logical block number of the block
34 *
35 * This function encrypt a possibly-compressed data in the data node.
36 * The encrypted data length will store in @out_len.
37 */
38int ubifs_encrypt(const struct inode *inode, struct ubifs_data_node *dn,
39		  unsigned int in_len, unsigned int *out_len, int block)
40{
41	struct ubifs_info *c = inode->i_sb->s_fs_info;
42	void *p = &dn->data;
43	unsigned int pad_len = round_up(in_len, UBIFS_CIPHER_BLOCK_SIZE);
44	int err;
45
46	ubifs_assert(c, pad_len <= *out_len);
47	dn->compr_size = cpu_to_le16(in_len);
48
49	/* pad to full block cipher length */
50	if (pad_len != in_len)
51		memset(p + in_len, 0, pad_len - in_len);
52
53	err = fscrypt_encrypt_block_inplace(inode, virt_to_page(p), pad_len,
54					    offset_in_page(p), block, GFP_NOFS);
55	if (err) {
56		ubifs_err(c, "fscrypt_encrypt_block_inplace() failed: %d", err);
57		return err;
58	}
59	*out_len = pad_len;
60
61	return 0;
62}
63
64int ubifs_decrypt(const struct inode *inode, struct ubifs_data_node *dn,
65		  unsigned int *out_len, int block)
66{
67	struct ubifs_info *c = inode->i_sb->s_fs_info;
68	int err;
69	unsigned int clen = le16_to_cpu(dn->compr_size);
70	unsigned int dlen = *out_len;
71
72	if (clen <= 0 || clen > UBIFS_BLOCK_SIZE || clen > dlen) {
73		ubifs_err(c, "bad compr_size: %i", clen);
74		return -EINVAL;
75	}
76
77	ubifs_assert(c, dlen <= UBIFS_BLOCK_SIZE);
78	err = fscrypt_decrypt_block_inplace(inode, virt_to_page(&dn->data),
79					    dlen, offset_in_page(&dn->data),
80					    block);
81	if (err) {
82		ubifs_err(c, "fscrypt_decrypt_block_inplace() failed: %d", err);
83		return err;
84	}
85	*out_len = clen;
86
87	return 0;
88}
89
90const struct fscrypt_operations ubifs_crypt_operations = {
91	.flags			= FS_CFLG_OWN_PAGES,
92	.key_prefix		= "ubifs:",
93	.get_context		= ubifs_crypt_get_context,
94	.set_context		= ubifs_crypt_set_context,
95	.empty_dir		= ubifs_crypt_empty_dir,
 
96};