1 #include "ubifs.h" 2 3 static int ubifs_crypt_get_context(struct inode *inode, void *ctx, size_t len) 4 { 5 return ubifs_xattr_get(inode, UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT, 6 ctx, len); 7 } 8 9 static int ubifs_crypt_set_context(struct inode *inode, const void *ctx, 10 size_t len, void *fs_data) 11 { 12 return ubifs_xattr_set(inode, UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT, 13 ctx, len, 0); 14 } 15 16 static bool ubifs_crypt_empty_dir(struct inode *inode) 17 { 18 return ubifs_check_dir_empty(inode) == 0; 19 } 20 21 static unsigned int ubifs_crypt_max_namelen(struct inode *inode) 22 { 23 if (S_ISLNK(inode->i_mode)) 24 return UBIFS_MAX_INO_DATA; 25 else 26 return UBIFS_MAX_NLEN; 27 } 28 29 int ubifs_encrypt(const struct inode *inode, struct ubifs_data_node *dn, 30 unsigned int in_len, unsigned int *out_len, int block) 31 { 32 struct ubifs_info *c = inode->i_sb->s_fs_info; 33 void *p = &dn->data; 34 struct page *ret; 35 unsigned int pad_len = round_up(in_len, UBIFS_CIPHER_BLOCK_SIZE); 36 37 ubifs_assert(pad_len <= *out_len); 38 dn->compr_size = cpu_to_le16(in_len); 39 40 /* pad to full block cipher length */ 41 if (pad_len != in_len) 42 memset(p + in_len, 0, pad_len - in_len); 43 44 ret = fscrypt_encrypt_page(inode, virt_to_page(&dn->data), pad_len, 45 offset_in_page(&dn->data), block, GFP_NOFS); 46 if (IS_ERR(ret)) { 47 ubifs_err(c, "fscrypt_encrypt_page failed: %ld", PTR_ERR(ret)); 48 return PTR_ERR(ret); 49 } 50 *out_len = pad_len; 51 52 return 0; 53 } 54 55 int ubifs_decrypt(const struct inode *inode, struct ubifs_data_node *dn, 56 unsigned int *out_len, int block) 57 { 58 struct ubifs_info *c = inode->i_sb->s_fs_info; 59 int err; 60 unsigned int clen = le16_to_cpu(dn->compr_size); 61 unsigned int dlen = *out_len; 62 63 if (clen <= 0 || clen > UBIFS_BLOCK_SIZE || clen > dlen) { 64 ubifs_err(c, "bad compr_size: %i", clen); 65 return -EINVAL; 66 } 67 68 ubifs_assert(dlen <= UBIFS_BLOCK_SIZE); 69 err = fscrypt_decrypt_page(inode, virt_to_page(&dn->data), dlen, 70 offset_in_page(&dn->data), block); 71 if (err) { 72 ubifs_err(c, "fscrypt_decrypt_page failed: %i", err); 73 return err; 74 } 75 *out_len = clen; 76 77 return 0; 78 } 79 80 const struct fscrypt_operations ubifs_crypt_operations = { 81 .flags = FS_CFLG_OWN_PAGES, 82 .key_prefix = "ubifs:", 83 .get_context = ubifs_crypt_get_context, 84 .set_context = ubifs_crypt_set_context, 85 .is_encrypted = __ubifs_crypt_is_encrypted, 86 .empty_dir = ubifs_crypt_empty_dir, 87 .max_namelen = ubifs_crypt_max_namelen, 88 }; 89