diff options
| -rw-r--r-- | Documentation/filesystems/fscrypt.rst | 10 | ||||
| -rw-r--r-- | fs/crypto/crypto.c | 1 | ||||
| -rw-r--r-- | fs/crypto/fname.c | 140 | ||||
| -rw-r--r-- | fs/crypto/fscrypt_private.h | 31 | ||||
| -rw-r--r-- | fs/crypto/hooks.c | 158 | ||||
| -rw-r--r-- | fs/crypto/keyinfo.c | 17 | ||||
| -rw-r--r-- | fs/ext4/namei.c | 58 | ||||
| -rw-r--r-- | fs/ext4/super.c | 4 | ||||
| -rw-r--r-- | fs/ext4/symlink.c | 43 | ||||
| -rw-r--r-- | fs/f2fs/inode.c | 2 | ||||
| -rw-r--r-- | fs/f2fs/namei.c | 132 | ||||
| -rw-r--r-- | fs/ubifs/dir.c | 63 | ||||
| -rw-r--r-- | fs/ubifs/file.c | 36 | ||||
| -rw-r--r-- | fs/ubifs/super.c | 4 | ||||
| -rw-r--r-- | include/linux/fscrypt.h | 174 | ||||
| -rw-r--r-- | include/linux/fscrypt_notsupp.h | 59 | ||||
| -rw-r--r-- | include/linux/fscrypt_supp.h | 68 |
17 files changed, 500 insertions, 500 deletions
diff --git a/Documentation/filesystems/fscrypt.rst b/Documentation/filesystems/fscrypt.rst index 776ddc655f79..cfbc18f0d9c9 100644 --- a/Documentation/filesystems/fscrypt.rst +++ b/Documentation/filesystems/fscrypt.rst @@ -448,8 +448,14 @@ astute users may notice some differences in behavior: - The st_size of an encrypted symlink will not necessarily give the length of the symlink target as required by POSIX. It will actually - give the length of the ciphertext, which may be slightly longer than - the plaintext due to the NUL-padding. + give the length of the ciphertext, which will be slightly longer + than the plaintext due to NUL-padding and an extra 2-byte overhead. + +- The maximum length of an encrypted symlink is 2 bytes shorter than + the maximum length of an unencrypted symlink. For example, on an + EXT4 filesystem with a 4K block size, unencrypted symlinks can be up + to 4095 bytes long, while encrypted symlinks can only be up to 4093 + bytes long (both lengths excluding the terminating null). Note that mmap *is* supported. This is possible because the pagecache for an encrypted file contains the plaintext, not the ciphertext. diff --git a/fs/crypto/crypto.c b/fs/crypto/crypto.c index 732a786cce9d..ce654526c0fb 100644 --- a/fs/crypto/crypto.c +++ b/fs/crypto/crypto.c @@ -27,6 +27,7 @@ #include <linux/dcache.h> #include <linux/namei.h> #include <crypto/aes.h> +#include <crypto/skcipher.h> #include "fscrypt_private.h" static unsigned int num_prealloc_crypto_pages = 32; diff --git a/fs/crypto/fname.c b/fs/crypto/fname.c index 305541bcd108..e33f3d3c5ade 100644 --- a/fs/crypto/fname.c +++ b/fs/crypto/fname.c @@ -13,42 +13,46 @@ #include <linux/scatterlist.h> #include <linux/ratelimit.h> +#include <crypto/skcipher.h> #include "fscrypt_private.h" +static inline bool fscrypt_is_dot_dotdot(const struct qstr *str) +{ + if (str->len == 1 && str->name[0] == '.') + return true; + + if (str->len == 2 && str->name[0] == '.' && str->name[1] == '.') + return true; + + return false; +} + /** * fname_encrypt() - encrypt a filename * - * The caller must have allocated sufficient memory for the @oname string. + * The output buffer must be at least as large as the input buffer. + * Any extra space is filled with NUL padding before encryption. * * Return: 0 on success, -errno on failure */ -static int fname_encrypt(struct inode *inode, - const struct qstr *iname, struct fscrypt_str *oname) +int fname_encrypt(struct inode *inode, const struct qstr *iname, + u8 *out, unsigned int olen) { struct skcipher_request *req = NULL; DECLARE_CRYPTO_WAIT(wait); - struct fscrypt_info *ci = inode->i_crypt_info; - struct crypto_skcipher *tfm = ci->ci_ctfm; + struct crypto_skcipher *tfm = inode->i_crypt_info->ci_ctfm; int res = 0; char iv[FS_CRYPTO_BLOCK_SIZE]; struct scatterlist sg; - int padding = 4 << (ci->ci_flags & FS_POLICY_FLAGS_PAD_MASK); - unsigned int lim; - unsigned int cryptlen; - - lim = inode->i_sb->s_cop->max_namelen(inode); - if (iname->len <= 0 || iname->len > lim) - return -EIO; /* * Copy the filename to the output buffer for encrypting in-place and * pad it with the needed number of NUL bytes. */ - cryptlen = max_t(unsigned int, iname->len, FS_CRYPTO_BLOCK_SIZE); - cryptlen = round_up(cryptlen, padding); - cryptlen = min(cryptlen, lim); - memcpy(oname->name, iname->name, iname->len); - memset(oname->name + iname->len, 0, cryptlen - iname->len); + if (WARN_ON(olen < iname->len)) + return -ENOBUFS; + memcpy(out, iname->name, iname->len); + memset(out + iname->len, 0, olen - iname->len); /* Initialize the IV */ memset(iv, 0, FS_CRYPTO_BLOCK_SIZE); @@ -63,8 +67,8 @@ static int fname_encrypt(struct inode *inode, skcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP, crypto_req_done, &wait); - sg_init_one(&sg, oname->name, cryptlen); - skcipher_request_set_crypt(req, &sg, &sg, cryptlen, iv); + sg_init_one(&sg, out, olen); + skcipher_request_set_crypt(req, &sg, &sg, olen, iv); /* Do the encryption */ res = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); @@ -75,7 +79,6 @@ static int fname_encrypt(struct inode *inode, return res; } - oname->len = cryptlen; return 0; } @@ -188,50 +191,52 @@ static int digest_decode(const char *src, int len, char *dst) return cp - dst; } -u32 fscrypt_fname_encrypted_size(const struct inode *inode, u32 ilen) +bool fscrypt_fname_encrypted_size(const struct inode *inode, u32 orig_len, + u32 max_len, u32 *encrypted_len_ret) { - int padding = 32; - struct fscrypt_info *ci = inode->i_crypt_info; - - if (ci) - padding = 4 << (ci->ci_flags & FS_POLICY_FLAGS_PAD_MASK); - ilen = max(ilen, (u32)FS_CRYPTO_BLOCK_SIZE); - return round_up(ilen, padding); + int padding = 4 << (inode->i_crypt_info->ci_flags & + FS_POLICY_FLAGS_PAD_MASK); + u32 encrypted_len; + + if (orig_len > max_len) + return false; + encrypted_len = max(orig_len, (u32)FS_CRYPTO_BLOCK_SIZE); + encrypted_len = round_up(encrypted_len, padding); + *encrypted_len_ret = min(encrypted_len, max_len); + return true; } -EXPORT_SYMBOL(fscrypt_fname_encrypted_size); /** - * fscrypt_fname_crypto_alloc_obuff() - + * fscrypt_fname_alloc_buffer - allocate a buffer for presented filenames + * + * Allocate a buffer that is large enough to hold any decrypted or encoded + * filename (null-terminated), for the given maximum encrypted filename length. * - * Allocates an output buffer that is sufficient for the crypto operation - * specified by the context and the direction. + * Return: 0 on success, -errno on failure */ int fscrypt_fname_alloc_buffer(const struct inode *inode, - u32 ilen, struct fscrypt_str *crypto_str) + u32 max_encrypted_len, + struct fscrypt_str *crypto_str) { - u32 olen = fscrypt_fname_encrypted_size(inode, ilen); const u32 max_encoded_len = max_t(u32, BASE64_CHARS(FSCRYPT_FNAME_MAX_UNDIGESTED_SIZE), 1 + BASE64_CHARS(sizeof(struct fscrypt_digested_name))); + u32 max_presented_len; - crypto_str->len = olen; - olen = max(olen, max_encoded_len); + max_presented_len = max(max_encoded_len, max_encrypted_len); - /* - * Allocated buffer can hold one more character to null-terminate the - * string - */ - crypto_str->name = kmalloc(olen + 1, GFP_NOFS); - if (!(crypto_str->name)) + crypto_str->name = kmalloc(max_presented_len + 1, GFP_NOFS); + if (!crypto_str->name) return -ENOMEM; + crypto_str->len = max_presented_len; return 0; } EXPORT_SYMBOL(fscrypt_fname_alloc_buffer); /** - * fscrypt_fname_crypto_free_buffer() - + * fscrypt_fname_free_buffer - free the buffer for presented filenames * - * Frees the buffer allocated for crypto operation. + * Free the buffer allocated by fscrypt_fname_alloc_buffer(). */ void fscrypt_fname_free_buffer(struct fscrypt_str *crypto_str) { @@ -298,35 +303,6 @@ int fscrypt_fname_disk_to_usr(struct inode *inode, EXPORT_SYMBOL(fscrypt_fname_disk_to_usr); /** - * fscrypt_fname_usr_to_disk() - converts a filename from user space to disk - * space - * - * The caller must have allocated sufficient memory for the @oname string. - * - * Return: 0 on success, -errno on failure - */ -int fscrypt_fname_usr_to_disk(struct inode *inode, - const struct qstr *iname, - struct fscrypt_str *oname) -{ - if (fscrypt_is_dot_dotdot(iname)) { - oname->name[0] = '.'; - oname->name[iname->len - 1] = '.'; - oname->len = iname->len; - return 0; - } - if (inode->i_crypt_info) - return fname_encrypt(inode, iname, oname); - /* - * Without a proper key, a user is not allowed to modify the filenames - * in a directory. Consequently, a user space name cannot be mapped to - * a disk-space name - */ - return -ENOKEY; -} -EXPORT_SYMBOL(fscrypt_fname_usr_to_disk); - -/** * fscrypt_setup_filename() - prepare to search a possibly encrypted directory * @dir: the directory that will be searched * @iname: the user-provided filename being searched for @@ -369,11 +345,17 @@ int fscrypt_setup_filename(struct inode *dir, const struct qstr *iname, return ret; if (dir->i_crypt_info) { - ret = fscrypt_fname_alloc_buffer(dir, iname->len, - &fname->crypto_buf); - if (ret) - return ret; - ret = fname_encrypt(dir, iname, &fname->crypto_buf); + if (!fscrypt_fname_encrypted_size(dir, iname->len, + dir->i_sb->s_cop->max_namelen(dir), + &fname->crypto_buf.len)) + return -ENAMETOOLONG; + fname->crypto_buf.name = kmalloc(fname->crypto_buf.len, + GFP_NOFS); + if (!fname->crypto_buf.name) + return -ENOMEM; + + ret = fname_encrypt(dir, iname, fname->crypto_buf.name, + fname->crypto_buf.len); if (ret) goto errout; fname->disk_name.name = fname->crypto_buf.name; @@ -425,7 +407,7 @@ int fscrypt_setup_filename(struct inode *dir, const struct qstr *iname, return 0; errout: - fscrypt_fname_free_buffer(&fname->crypto_buf); + kfree(fname->crypto_buf.name); return ret; } EXPORT_SYMBOL(fscrypt_setup_filename); diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h index c0b4f5597e1a..ad6722bae8b7 100644 --- a/fs/crypto/fscrypt_private.h +++ b/fs/crypto/fscrypt_private.h @@ -50,6 +50,15 @@ struct fscrypt_context { #define FS_ENCRYPTION_CONTEXT_FORMAT_V1 1 +/** + * For encrypted symlinks, the ciphertext length is stored at the beginning + * of the string in little-endian format. + */ +struct fscrypt_symlink_data { + __le16 len; + char encrypted_path[1]; +} __packed; + /* * A pointer to this structure is stored in the file system's in-core * representation of an inode. @@ -71,7 +80,22 @@ typedef enum { #define FS_CTX_REQUIRES_FREE_ENCRYPT_FL 0x00000001 #define FS_CTX_HAS_BOUNCE_BUFFER_FL 0x00000002 +static inline bool fscrypt_valid_enc_modes(u32 contents_mode, + u32 filenames_mode) +{ + if (contents_mode == FS_ENCRYPTION_MODE_AES_128_CBC && + filenames_mode == FS_ENCRYPTION_MODE_AES_128_CTS) + return true; + + if (contents_mode == FS_ENCRYPTION_MODE_AES_256_XTS && + filenames_mode == FS_ENCRYPTION_MODE_AES_256_CTS) + return true; + + return false; +} + /* crypto.c */ +extern struct kmem_cache *fscrypt_info_cachep; extern int fscrypt_initialize(unsigned int cop_flags); extern struct workqueue_struct *fscrypt_read_workqueue; extern int fscrypt_do_page_crypto(const struct inode *inode, @@ -83,6 +107,13 @@ extern int fscrypt_do_page_crypto(const struct inode *inode, extern struct page *fscrypt_alloc_bounce_page(struct fscrypt_ctx *ctx, gfp_t gfp_flags); +/* fname.c */ +extern int fname_encrypt(struct inode *inode, const struct qstr *iname, + u8 *out, unsigned int olen); +extern bool fscrypt_fname_encrypted_size(const struct inode *inode, + u32 orig_len, u32 max_len, + u32 *encrypted_len_ret); + /* keyinfo.c */ extern void __exit fscrypt_essiv_cleanup(void); diff --git a/fs/crypto/hooks.c b/fs/crypto/hooks.c index 9f5fb2eb9cf7..bec06490fb13 100644 --- a/fs/crypto/hooks.c +++ b/fs/crypto/hooks.c @@ -110,3 +110,161 @@ int __fscrypt_prepare_lookup(struct inode *dir, struct dentry *dentry) return 0; } EXPORT_SYMBOL_GPL(__fscrypt_prepare_lookup); + +int __fscrypt_prepare_symlink(struct inode *dir, unsigned int len, + unsigned int max_len, + struct fscrypt_str *disk_link) +{ + int err; + + /* + * To calculate the size of the encrypted symlink target we need to know + * the amount of NUL padding, which is determined by the flags set in + * the encryption policy which will be inherited from the directory. + * The easiest way to get access to this is to just load the directory's + * fscrypt_info, since we'll need it to create the dir_entry anyway. + * + * Note: in test_dummy_encryption mode, @dir may be unencrypted. + */ + err = fscrypt_get_encryption_info(dir); + if (err) + return err; + if (!fscrypt_has_encryption_key(dir)) + return -ENOKEY; + + /* + * Calculate the size of the encrypted symlink and verify it won't + * exceed max_len. Note that for historical reasons, encrypted symlink + * targets are prefixed with the ciphertext length, despite this + * actually being redundant with i_size. This decreases by 2 bytes the + * longest symlink target we can accept. + * + * We could recover 1 byte by not counting a null terminator, but + * counting it (even though it is meaningless for ciphertext) is simpler + * for now since filesystems will assume it is there and subtract it. + */ + if (!fscrypt_fname_encrypted_size(dir, len, + max_len - sizeof(struct fscrypt_symlink_data), + &disk_link->len)) + return -ENAMETOOLONG; + disk_link->len += sizeof(struct fscrypt_symlink_data); + + disk_link->name = NULL; + return 0; +} +EXPORT_SYMBOL_GPL(__fscrypt_prepare_symlink); + +int __fscrypt_encrypt_symlink(struct inode *inode, const char *target, + unsigned int len, struct fscrypt_str *disk_link) +{ + int err; + struct qstr iname = QSTR_INIT(target, len); + struct fscrypt_symlink_data *sd; + unsigned int ciphertext_len; + + err = fscrypt_require_key(inode); + if (err) + return err; + + if (disk_link->name) { + /* filesystem-provided buffer */ + sd = (struct fscrypt_symlink_data *)disk_link->name; + } else { + sd = kmalloc(disk_link->len, GFP_NOFS); + if (!sd) + return -ENOMEM; + } + ciphertext_len = disk_link->len - sizeof(*sd); + sd->len = cpu_to_le16(ciphertext_len); + + err = fname_encrypt(inode, &iname, sd->encrypted_path, ciphertext_len); + if (err) { + if (!disk_link->name) + kfree(sd); + return err; + } + /* + * Null-terminating the ciphertext doesn't make sense, but we still + * count the null terminator in the length, so we might as well + * initialize it just in case the filesystem writes it out. + */ + sd->encrypted_path[ciphertext_len] = '\0'; + + if (!disk_link->name) + disk_link->name = (unsigned char *)sd; + return 0; +} +EXPORT_SYMBOL_GPL(__fscrypt_encrypt_symlink); + +/** + * fscrypt_get_symlink - get the target of an encrypted symlink + * @inode: the symlink inode + * @caddr: the on-disk contents of the symlink + * @max_size: size of @caddr buffer + * @done: if successful, will be set up to free the returned target + * + * If the symlink's encryption key is available, we decrypt its target. + * Otherwise, we encode its target for presentation. + * + * This may sleep, so the filesystem must have dropped out of RCU mode already. + * + * Return: the presentable symlink target or an ERR_PTR() + */ +const char *fscrypt_get_symlink(struct inode *inode, const void *caddr, + unsigned int max_size, + struct delayed_call *done) +{ + const struct fscrypt_symlink_data *sd; + struct fscrypt_str cstr, pstr; + int err; + + /* This is for encrypted symlinks only */ + if (WARN_ON(!IS_ENCRYPTED(inode))) + return ERR_PTR(-EINVAL); + + /* + * Try to set up the symlink's encryption key, but we can continue + * regardless of whether the key is available or not. + */ + err = fscrypt_get_encryption_info(inode); + if (err) + return ERR_PTR(err); + + /* + * For historical reasons, encrypted symlink targets are prefixed with + * the ciphertext length, even though this is redundant with i_size. + */ + + if (max_size < sizeof(*sd)) + return ERR_PTR(-EUCLEAN); + sd = caddr; + cstr.name = (unsigned char *)sd->encrypted_path; + cstr.len = le16_to_cpu(sd->len); + + if (cstr.len == 0) + return ERR_PTR(-EUCLEAN); + + if (cstr.len + sizeof(*sd) - 1 > max_size) + return ERR_PTR(-EUCLEAN); + + err = fscrypt_fname_alloc_buffer(inode, cstr.len, &pstr); + if (err) + return ERR_PTR(err); + + err = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr); + if (err) + goto err_kfree; + + err = -EUCLEAN; + if (pstr.name[0] == '\0') + goto err_kfree; + + pstr.name[pstr.len] = '\0'; + set_delayed_call(done, kfree_link, pstr.name); + return pstr.name; + +err_kfree: + kfree(pstr.name); + return ERR_PTR(err); +} +EXPORT_SYMBOL_GPL(fscrypt_get_symlink); diff --git a/fs/crypto/keyinfo.c b/fs/crypto/keyinfo.c index 5e6e846f5a24..05f5ee1f0705 100644 --- a/fs/crypto/keyinfo.c +++ b/fs/crypto/keyinfo.c @@ -14,6 +14,7 @@ #include <linux/ratelimit.h> #include <crypto/aes.h> #include <crypto/sha.h> +#include <crypto/skcipher.h> #include "fscrypt_private.h" static struct crypto_shash *essiv_hash_tfm; @@ -354,19 +355,9 @@ out: } EXPORT_SYMBOL(fscrypt_get_encryption_info); -void fscrypt_put_encryption_info(struct inode *inode, struct fscrypt_info *ci) +void fscrypt_put_encryption_info(struct inode *inode) { - struct fscrypt_info *prev; - - if (ci == NULL) - ci = READ_ONCE(inode->i_crypt_info); - if (ci == NULL) - return; - - prev = cmpxchg(&inode->i_crypt_info, ci, NULL); - if (prev != ci) - return; - - put_crypt_info(ci); + put_crypt_info(inode->i_crypt_info); + inode->i_crypt_info = NULL; } EXPORT_SYMBOL(fscrypt_put_encryption_info); diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index 9aa1deb1a525..b1f21e3a0763 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -3057,39 +3057,19 @@ static int ext4_symlink(struct inode *dir, struct inode *inode; int err, len = strlen(symname); int credits; - bool encryption_required; struct fscrypt_str disk_link; - struct fscrypt_symlink_data *sd = NULL; if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) return -EIO; - disk_link.len = len + 1; - disk_link.name = (char *) symname; - - encryption_required = (ext4_encrypted_inode(dir) || - DUMMY_ENCRYPTION_ENABLED(EXT4_SB(dir->i_sb))); - if (encryption_required) { - err = fscrypt_get_encryption_info(dir); - if (err) - return err; - if (!fscrypt_has_encryption_key(dir)) - return -ENOKEY; - disk_link.len = (fscrypt_fname_encrypted_size(dir, len) + - sizeof(struct fscrypt_symlink_data)); - sd = kzalloc(disk_link.len, GFP_KERNEL); - if (!sd) - return -ENOMEM; - } - - if (disk_link.len > dir->i_sb->s_blocksize) { - err = -ENAMETOOLONG; - goto err_free_sd; - } + err = fscrypt_prepare_symlink(dir, symname, len, dir->i_sb->s_blocksize, + &disk_link); + if (err) + return err; err = dquot_initialize(dir); if (err) - goto err_free_sd; + return err; if ((disk_link.len > EXT4_N_BLOCKS * 4)) { /* @@ -3118,27 +3098,18 @@ static int ext4_symlink(struct inode *dir, if (IS_ERR(inode)) { if (handle) ext4_journal_stop(handle); - err = PTR_ERR(inode); - goto err_free_sd; + return PTR_ERR(inode); } - if (encryption_required) { - struct qstr istr; - struct fscrypt_str ostr = - FSTR_INIT(sd->encrypted_path, disk_link.len); - - istr.name = (const unsigned char *) symname; - istr.len = len; - err = fscrypt_fname_usr_to_disk(inode, &istr, &ostr); + if (IS_ENCRYPTED(inode)) { + err = fscrypt_encrypt_symlink(inode, symname, len, &disk_link); if (err) goto err_drop_inode; - sd->len = cpu_to_le16(ostr.len); - disk_link.name = (char *) sd; inode->i_op = &ext4_encrypted_symlink_inode_operations; } if ((disk_link.len > EXT4_N_BLOCKS * 4)) { - if (!encryption_required) + if (!IS_ENCRYPTED(inode)) inode->i_op = &ext4_symlink_inode_operations; inode_nohighmem(inode); ext4_set_aops(inode); @@ -3180,7 +3151,7 @@ static int ext4_symlink(struct inode *dir, } else { /* clear the extent format for fast symlink */ ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS); - if (!encryption_required) { + if (!IS_ENCRYPTED(inode)) { inode->i_op = &ext4_fast_symlink_inode_operations; inode->i_link = (char *)&EXT4_I(inode)->i_data; } @@ -3195,16 +3166,17 @@ static int ext4_symlink(struct inode *dir, if (handle) ext4_journal_stop(handle); - kfree(sd); - return err; + goto out_free_encrypted_link; + err_drop_inode: if (handle) ext4_journal_stop(handle); clear_nlink(inode); unlock_new_inode(inode); iput(inode); -err_free_sd: - kfree(sd); +out_free_encrypted_link: + if (disk_link.name != (unsigned char *)symname) + kfree(disk_link.name); return err; } diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 899e6faf3381..421222ec3509 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1073,9 +1073,7 @@ void ext4_clear_inode(struct inode *inode) jbd2_free_inode(EXT4_I(inode)->jinode); EXT4_I(inode)->jinode = NULL; } -#ifdef CONFIG_EXT4_FS_ENCRYPTION - fscrypt_put_encryption_info(inode, NULL); -#endif + fscrypt_put_encryption_info(inode); } static struct inode *ext4_nfs_get_inode(struct super_block *sb, diff --git a/fs/ext4/symlink.c b/fs/ext4/symlink.c index a2006c9af1d9..dd05af983092 100644 --- a/fs/ext4/symlink.c +++ b/fs/ext4/symlink.c @@ -28,59 +28,28 @@ static const char *ext4_encrypted_get_link(struct dentry *dentry, struct delayed_call *done) { struct page *cpage = NULL; - char *caddr, *paddr = NULL; - struct fscrypt_str cstr, pstr; - struct fscrypt_symlink_data *sd; - int res; - u32 max_size = inode->i_sb->s_blocksize; + const void *caddr; + unsigned int max_size; + const char *paddr; if (!dentry) return ERR_PTR(-ECHILD); - res = fscrypt_get_encryption_info(inode); - if (res) - return ERR_PTR(res); - if (ext4_inode_is_fast_symlink(inode)) { - caddr = (char *) EXT4_I(inode)->i_data; + caddr = EXT4_I(inode)->i_data; max_size = sizeof(EXT4_I(inode)->i_data); } else { cpage = read_mapping_page(inode->i_mapping, 0, NULL); if (IS_ERR(cpage)) return ERR_CAST(cpage); caddr = page_address(cpage); + max_size = inode->i_sb->s_blocksize; } - /* Symlink is encrypted */ - sd = (struct fscrypt_symlink_data *)caddr; - cstr.name = sd->encrypted_path; - cstr.len = le16_to_cpu(sd->len); - if ((cstr.len + sizeof(struct fscrypt_symlink_data) - 1) > max_size) { - /* Symlink data on the disk is corrupted */ - res = -EFSCORRUPTED; - goto errout; - } - - res = fscrypt_fname_alloc_buffer(inode, cstr.len, &pstr); - if (res) - goto errout; - paddr = pstr.name; - - res = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr); - if (res) - goto errout; - - /* Null-terminate the name */ - paddr[pstr.len] = '\0'; + paddr = fscrypt_get_symlink(inode, caddr, max_size, done); if (cpage) put_page(cpage); - set_delayed_call(done, kfree_link, paddr); return paddr; -errout: - if (cpage) - put_page(cpage); - kfree(paddr); - return ERR_PTR(res); } const struct inode_operations ext4_encrypted_symlink_inode_operations = { diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c index 89c838bfb067..205add3d0f3a 100644 --- a/fs/f2fs/inode.c +++ b/fs/f2fs/inode.c @@ -585,7 +585,7 @@ no_delete: !exist_written_data(sbi, inode->i_ino, ORPHAN_INO)); } out_clear: - fscrypt_put_encryption_info(inode, NULL); + fscrypt_put_encryption_info(inode); clear_inode(inode); } diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c index c4c94c7e9f4f..b68e7b03959f 100644 --- a/fs/f2fs/namei.c +++ b/fs/f2fs/namei.c @@ -486,27 +486,16 @@ static int f2fs_symlink(struct inode *dir, struct dentry *dentry, struct f2fs_sb_info *sbi = F2FS_I_SB(dir); struct inode *inode; size_t len = strlen(symname); - struct fscrypt_str disk_link = FSTR_INIT((char *)symname, len + 1); - struct fscrypt_symlink_data *sd = NULL; + struct fscrypt_str disk_link; int err; if (unlikely(f2fs_cp_error(sbi))) return -EIO; - if (f2fs_encrypted_inode(dir)) { - err = fscrypt_get_encryption_info(dir); - if (err) - return err; - - if (!fscrypt_has_encryption_key(dir)) - return -ENOKEY; - - disk_link.len = (fscrypt_fname_encrypted_size(dir, len) + - sizeof(struct fscrypt_symlink_data)); - } - - if (disk_link.len > dir->i_sb->s_blocksize) - return -ENAMETOOLONG; + err = fscrypt_prepare_symlink(dir, symname, len, dir->i_sb->s_blocksize, + &disk_link); + if (err) + return err; err = dquot_initialize(dir); if (err) @@ -516,7 +505,7 @@ static int f2fs_symlink(struct inode *dir, struct dentry *dentry, if (IS_ERR(inode)) return PTR_ERR(inode); - if (f2fs_encrypted_inode(inode)) + if (IS_ENCRYPTED(inode)) inode->i_op = &f2fs_encrypted_symlink_inode_operations; else inode->i_op = &f2fs_symlink_inode_operations; @@ -526,38 +515,13 @@ static int f2fs_symlink(struct inode *dir, struct dentry *dentry, f2fs_lock_op(sbi); err = f2fs_add_link(dentry, inode); if (err) - goto out; + goto out_handle_failed_inode; f2fs_unlock_op(sbi); alloc_nid_done(sbi, inode->i_ino); - if (f2fs_encrypted_inode(inode)) { - struct qstr istr = QSTR_INIT(symname, len); - struct fscrypt_str ostr; - - sd = f2fs_kzalloc(sbi, disk_link.len, GFP_NOFS); - if (!sd) { - err = -ENOMEM; - goto err_out; - } - - err = fscrypt_get_encryption_info(inode); - if (err) - goto err_out; - - if (!fscrypt_has_encryption_key(inode)) { - err = -ENOKEY; - goto err_out; - } - - ostr.name = sd->encrypted_path; - ostr.len = disk_link.len; - err = fscrypt_fname_usr_to_disk(inode, &istr, &ostr); - if (err) - goto err_out; - - sd->len = cpu_to_le16(ostr.len); - disk_link.name = (char *)sd; - } + err = fscrypt_encrypt_symlink(inode, symname, len, &disk_link); + if (err) + goto err_out; err = page_symlink(inode, disk_link.name, disk_link.len); @@ -584,12 +548,14 @@ err_out: f2fs_unlink(dir, dentry); } - kfree(sd); - f2fs_balance_fs(sbi, true); - return err; -out: + goto out_free_encrypted_link; + +out_handle_failed_inode: handle_failed_inode(inode); +out_free_encrypted_link: + if (disk_link.name != (unsigned char *)symname) + kfree(disk_link.name); return err; } @@ -1148,68 +1114,20 @@ static const char *f2fs_encrypted_get_link(struct dentry *dentry, struct inode *inode, struct delayed_call *done) { - struct page *cpage = NULL; - char *caddr, *paddr = NULL; - struct fscrypt_str cstr = FSTR_INIT(NULL, 0); - struct fscrypt_str pstr = FSTR_INIT(NULL, 0); - struct fscrypt_symlink_data *sd; - u32 max_size = inode->i_sb->s_blocksize; - int res; + struct page *page; + const char *target; if (!dentry) return ERR_PTR(-ECHILD); - res = fscrypt_get_encryption_info(inode); - if (res) - return ERR_PTR(res); - - cpage = read_mapping_page(inode->i_mapping, 0, NULL); - if (IS_ERR(cpage)) - return ERR_CAST(cpage); - caddr = page_address(cpage); - - /* Symlink is encrypted */ - sd = (struct fscrypt_symlink_data *)caddr; - cstr.name = sd->encrypted_path; - cstr.len = le16_to_cpu(sd->len); - - /* this is broken symlink case */ - if (unlikely(cstr.len == 0)) { - res = -ENOENT; - goto errout; - } - - if ((cstr.len + sizeof(struct fscrypt_symlink_data) - 1) > max_size) { - /* Symlink data on the disk is corrupted */ - res = -EIO; - goto errout; - } - res = fscrypt_fname_alloc_buffer(inode, cstr.len, &pstr); - if (res) - goto errout; - - res = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr); - if (res) - goto errout; - - /* this is broken symlink case */ - if (unlikely(pstr.name[0] == 0)) { - res = -ENOENT; - goto errout; - } - - paddr = pstr.name; - - /* Null-terminate the name */ - paddr[pstr.len] = '\0'; + page = read_mapping_page(inode->i_mapping, 0, NULL); + if (IS_ERR(page)) + return ERR_CAST(page); - put_page(cpage); - set_delayed_call(done, kfree_link, paddr); - return paddr; -errout: - fscrypt_fname_free_buffer(&pstr); - put_page(cpage); - return ERR_PTR(res); + target = fscrypt_get_symlink(inode, page_address(page), + inode->i_sb->s_blocksize, done); + put_page(page); + return target; } const struct inode_operations f2fs_encrypted_symlink_inode_operations = { diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c index a2ea4856e67b..9d7fb88e172e 100644 --- a/fs/ubifs/dir.c +++ b/fs/ubifs/dir.c @@ -1138,38 +1138,24 @@ static int ubifs_symlink(struct inode *dir, struct dentry *dentry, struct ubifs_info *c = dir->i_sb->s_fs_info; int err, len = strlen(symname); int sz_change = CALC_DENT_SIZE(len); - struct fscrypt_str disk_link = FSTR_INIT((char *)symname, len + 1); - struct fscrypt_symlink_data *sd = NULL; + struct fscrypt_str disk_link; struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1, .new_ino_d = ALIGN(len, 8), .dirtied_ino = 1 }; struct fscrypt_name nm; - if (ubifs_crypt_is_encrypted(dir)) { - err = fscrypt_get_encryption_info(dir); - if (err) - goto out_budg; - - if (!fscrypt_has_encryption_key(dir)) { - err = -EPERM; - goto out_budg; - } + dbg_gen("dent '%pd', target '%s' in dir ino %lu", dentry, + symname, dir->i_ino); - disk_link.len = (fscrypt_fname_encrypted_size(dir, len) + - sizeof(struct fscrypt_symlink_data)); - } + err = fscrypt_prepare_symlink(dir, symname, len, UBIFS_MAX_INO_DATA, + &disk_link); + if (err) + return err; /* * Budget request settings: new inode, new direntry and changing parent * directory inode. */ - - dbg_gen("dent '%pd', target '%s' in dir ino %lu", dentry, - symname, dir->i_ino); - - if (disk_link.len > UBIFS_MAX_INO_DATA) - return -ENAMETOOLONG; - err = ubifs_budget_space(c, &req); if (err) return err; @@ -1191,38 +1177,20 @@ static int ubifs_symlink(struct inode *dir, struct dentry *dentry, goto out_inode; } - if (ubifs_crypt_is_encrypted(dir)) { - struct qstr istr = QSTR_INIT(symname, len); - struct fscrypt_str ostr; - - sd = kzalloc(disk_link.len, GFP_NOFS); - if (!sd) { - err = -ENOMEM; - goto out_inode; - } - - ostr.name = sd->encrypted_path; - ostr.len = disk_link.len; - - err = fscrypt_fname_usr_to_disk(inode, &istr, &ostr); - if (err) { - kfree(sd); + if (IS_ENCRYPTED(inode)) { + disk_link.name = ui->data; /* encrypt directly into ui->data */ + err = fscrypt_encrypt_symlink(inode, symname, len, &disk_link); + if (err) goto out_inode; - } - - sd->len = cpu_to_le16(ostr.len); - disk_link.name = (char *)sd; } else { + memcpy(ui->data, disk_link.name, disk_link.len); inode->i_link = ui->data; } - memcpy(ui->data, disk_link.name, disk_link.len); - ((char *)ui->data)[disk_link.len - 1] = '\0'; - /* * The terminating zero byte is not written to the flash media and it * is put just to make later in-memory string processing simpler. Thus, - * data length is @len, not @len + %1. + * data length is @disk_link.len - 1, not @disk_link.len. */ ui->data_len = disk_link.len - 1; inode->i_size = ubifs_inode(inode)->ui_size = disk_link.len - 1; @@ -1240,11 +1208,10 @@ static int ubifs_symlink(struct inode *dir, struct dentry *dentry, goto out_cancel; mutex_unlock(&dir_ui->ui_mutex); - ubifs_release_budget(c, &req); insert_inode_hash(inode); d_instantiate(dentry, inode); - fscrypt_free_filename(&nm); - return 0; + err = 0; + goto out_fname; out_cancel: dir->i_size -= sz_change; diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c index 9fe194a4fa9b..cf348ba99238 100644 --- a/fs/ubifs/file.c +++ b/fs/ubifs/file.c @@ -1629,49 +1629,17 @@ static const char *ubifs_get_link(struct dentry *dentry, struct inode *inode, struct delayed_call *done) { - int err; - struct fscrypt_symlink_data *sd; struct ubifs_inode *ui = ubifs_inode(inode); - struct fscrypt_str cstr; - struct fscrypt_str pstr; - if (!ubifs_crypt_is_encrypted(inode)) + if (!IS_ENCRYPTED(inode)) return ui->data; if (!dentry) return ERR_PTR(-ECHILD); - err = fscrypt_get_encryption_info(inode); - if (err) - return ERR_PTR(err); - - sd = (struct fscrypt_symlink_data *)ui->data; - cstr.name = sd->encrypted_path; - cstr.len = le16_to_cpu(sd->len); - - if (cstr.len == 0) - return ERR_PTR(-ENOENT); - - if ((cstr.len + sizeof(struct fscrypt_symlink_data) - 1) > ui->data_len) - return ERR_PTR(-EIO); - - err = fscrypt_fname_alloc_buffer(inode, cstr.len, &pstr); - if (err) - return ERR_PTR(err); - - err = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr); - if (err) { - fscrypt_fname_free_buffer(&pstr); - return ERR_PTR(err); - } - - pstr.name[pstr.len] = '\0'; - - set_delayed_call(done, kfree_link, pstr.name); - return pstr.name; + return fscrypt_get_symlink(inode, ui->data, ui->data_len, done); } - const struct address_space_operations ubifs_file_address_operations = { .readpage = ubifs_readpage, .writepage = ubifs_writepage, diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c index 0beb285b143d..b16ef162344a 100644 --- a/fs/ubifs/super.c +++ b/fs/ubifs/super.c @@ -379,9 +379,7 @@ out: } done: clear_inode(inode); -#ifdef CONFIG_UBIFS_FS_ENCRYPTION - fscrypt_put_encryption_info(inode, NULL); -#endif + fscrypt_put_encryption_info(inode); } static void ubifs_dirty_inode(struct inode *inode, int flags) diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h index 08b4b40c5aa8..952ab97af325 100644 --- a/include/linux/fscrypt.h +++ b/include/linux/fscrypt.h @@ -14,42 +14,13 @@ #ifndef _LINUX_FSCRYPT_H #define _LINUX_FSCRYPT_H -#include <linux/key.h> #include <linux/fs.h> -#include <linux/mm.h> -#include <linux/bio.h> -#include <linux/dcache.h> -#include <crypto/skcipher.h> -#include <uapi/linux/fs.h> #define FS_CRYPTO_BLOCK_SIZE 16 +struct fscrypt_ctx; struct fscrypt_info; -struct fscrypt_ctx { - union { - struct { - struct page *bounce_page; /* Ciphertext page */ - struct page *control_page; /* Original page */ - } w; - struct { - struct bio *bio; - struct work_struct work; - } r; - struct list_head free_list; /* Free list */ - }; - u8 flags; /* Flags */ -}; - -/** - * For encrypted symlinks, the ciphertext length is stored at the beginning - * of the string in little-endian format. - */ -struct fscrypt_symlink_data { - __le16 len; - char encrypted_path[1]; -} __packed; - struct fscrypt_str { unsigned char *name; u32 len; @@ -68,89 +39,14 @@ struct fscrypt_name { #define fname_name(p) ((p)->disk_name.name) #define fname_len(p) ((p)->disk_name.len) -/* - * fscrypt superblock flags - */ -#define FS_CFLG_OWN_PAGES (1U << 1) - -/* - * crypto opertions for filesystems - */ -struct fscrypt_operations { - unsigned int flags; - const char *key_prefix; - int (*get_context)(struct inode *, void *, size_t); - int (*set_context)(struct inode *, const void *, size_t, void *); - bool (*dummy_context)(struct inode *); - bool (*empty_dir)(struct inode *); - unsigned (*max_namelen)(struct inode *); -}; - /* Maximum value for the third parameter of fscrypt_operations.set_context(). */ #define FSCRYPT_SET_CONTEXT_MAX_SIZE 28 -static inline bool fscrypt_dummy_context_enabled(struct inode *inode) -{ - if (inode->i_sb->s_cop->dummy_context && - inode->i_sb->s_cop->dummy_context(inode)) - return true; - return false; -} - -static inline bool fscrypt_valid_enc_modes(u32 contents_mode, - u32 filenames_mode) -{ - if (contents_mode == FS_ENCRYPTION_MODE_AES_128_CBC && - filenames_mode == FS_ENCRYPTION_MODE_AES_128_CTS) - return true; - - if (contents_mode == FS_ENCRYPTION_MODE_AES_256_XTS && - filenames_mode == FS_ENCRYPTION_MODE_AES_256_CTS) - return true; - - return false; -} - -static inline bool fscrypt_is_dot_dotdot(const struct qstr *str) -{ - if (str->len == 1 && str->name[0] == '.') - return true; - - if (str->len == 2 && str->name[0] == '.' && str->name[1] == '.') - return true; - - return false; -} - #if __FS_HAS_ENCRYPTION - -static inline struct page *fscrypt_control_page(struct page *page) -{ - return ((struct fscrypt_ctx *)page_private(page))->w.control_page; -} - -static inline bool fscrypt_has_encryption_key(const struct inode *inode) -{ - return (inode->i_crypt_info != NULL); -} - #include <linux/fscrypt_supp.h> - -#else /* !__FS_HAS_ENCRYPTION */ - -static inline struct page *fscrypt_control_page(struct page *page) -{ - WARN_ON_ONCE(1); - return ERR_PTR(-EINVAL); -} - -static inline bool fscrypt_has_encryption_key(const struct inode *inode) -{ - return 0; -} - +#else #include <linux/fscrypt_notsupp.h> -#endif /* __FS_HAS_ENCRYPTION */ +#endif /** * fscrypt_require_key - require an inode's encryption key @@ -291,4 +187,68 @@ static inline int fscrypt_prepare_setattr(struct dentry *dentry, return 0; } +/** + * fscrypt_prepare_symlink - prepare to create a possibly-encrypted symlink + * @dir: directory in which the symlink is being created + * @target: plaintext symlink target + * @len: length of @target excluding null terminator + * @max_len: space the filesystem has available to store the symlink target + * @disk_link: (out) the on-disk symlink target being prepared + * + * This function computes the size the symlink target will require on-disk, + * stores it in @disk_link->len, and validates it against @max_len. An + * encrypted symlink may be longer than the original. + * + * Additionally, @disk_link->name is set to @target if the symlink will be + * unencrypted, but left NULL if the symlink will be encrypted. For encrypted + * symlinks, the filesystem must call fscrypt_encrypt_symlink() to create the + * on-disk target later. (The reason for the two-step process is that some + * filesystems need to know the size of the symlink target before creating the + * inode, e.g. to determine whether it will be a "fast" or "slow" symlink.) + * + * Return: 0 on success, -ENAMETOOLONG if the symlink target is too long, + * -ENOKEY if the encryption key is missing, or another -errno code if a problem + * occurred while setting up the encryption key. + */ +static inline int fscrypt_prepare_symlink(struct inode *dir, + const char *target, + unsigned int len, + unsigned int max_len, + struct fscrypt_str *disk_link) +{ + if (IS_ENCRYPTED(dir) || fscrypt_dummy_context_enabled(dir)) + return __fscrypt_prepare_symlink(dir, len, max_len, disk_link); + + disk_link->name = (unsigned char *)target; + disk_link->len = len + 1; + if (disk_link->len > max_len) + return -ENAMETOOLONG; + return 0; +} + +/** + * fscrypt_encrypt_symlink - encrypt the symlink target if needed + * @inode: symlink inode + * @target: plaintext symlink target + * @len: length of @target excluding null terminator + * @disk_link: (in/out) the on-disk symlink target being prepared + * + * If the symlink target needs to be encrypted, then this function encrypts it + * into @disk_link->name. fscrypt_prepare_symlink() must have been called + * previously to compute @disk_link->len. If the filesystem did not allocate a + * buffer for @disk_link->name after calling fscrypt_prepare_link(), then one + * will be kmalloc()'ed and the filesystem will be responsible for freeing it. + * + * Return: 0 on success, -errno on failure + */ +static inline int fscrypt_encrypt_symlink(struct inode *inode, + const char *target, + unsigned int len, + struct fscrypt_str *disk_link) +{ + if (IS_ENCRYPTED(inode)) + return __fscrypt_encrypt_symlink(inode, target, len, disk_link); + return 0; +} + #endif /* _LINUX_FSCRYPT_H */ diff --git a/include/linux/fscrypt_notsupp.h b/include/linux/fscrypt_notsupp.h index 63e58808519a..44b50c04bae9 100644 --- a/include/linux/fscrypt_notsupp.h +++ b/include/linux/fscrypt_notsupp.h @@ -14,6 +14,16 @@ #ifndef _LINUX_FSCRYPT_NOTSUPP_H #define _LINUX_FSCRYPT_NOTSUPP_H +static inline bool fscrypt_has_encryption_key(const struct inode *inode) +{ + return false; +} + +static inline bool fscrypt_dummy_context_enabled(struct inode *inode) +{ + return false; +} + /* crypto.c */ static inline struct fscrypt_ctx *fscrypt_get_ctx(const struct inode *inode, gfp_t gfp_flags) @@ -43,6 +53,11 @@ static inline int fscrypt_decrypt_page(const struct inode *inode, return -EOPNOTSUPP; } +static inline struct page *fscrypt_control_page(struct page *page) +{ + WARN_ON_ONCE(1); + return ERR_PTR(-EINVAL); +} static inline void fscrypt_restore_control_page(struct page *page) { @@ -90,8 +105,7 @@ static inline int fscrypt_get_encryption_info(struct inode *inode) return -EOPNOTSUPP; } -static inline void fscrypt_put_encryption_info(struct inode *inode, - struct fscrypt_info *ci) +static inline void fscrypt_put_encryption_info(struct inode *inode) { return; } @@ -116,16 +130,8 @@ static inline void fscrypt_free_filename(struct fscrypt_name *fname) return; } -static inline u32 fscrypt_fname_encrypted_size(const struct inode *inode, - u32 ilen) -{ - /* never happens */ - WARN_ON(1); - return 0; -} - static inline int fscrypt_fname_alloc_buffer(const struct inode *inode, - u32 ilen, + u32 max_encrypted_len, struct fscrypt_str *crypto_str) { return -EOPNOTSUPP; @@ -144,13 +150,6 @@ static inline int fscrypt_fname_disk_to_usr(struct inode *inode, return -EOPNOTSUPP; } -static inline int fscrypt_fname_usr_to_disk(struct inode *inode, - const struct qstr *iname, - struct fscrypt_str *oname) -{ - return -EOPNOTSUPP; -} - static inline bool fscrypt_match_name(const struct fscrypt_name *fname, const u8 *de_name, u32 de_name_len) { @@ -208,4 +207,28 @@ static inline int __fscrypt_prepare_lookup(struct inode *dir, return -EOPNOTSUPP; } +static inline int __fscrypt_prepare_symlink(struct inode *dir, + unsigned int len, + unsigned int max_len, + struct fscrypt_str *disk_link) +{ + return -EOPNOTSUPP; +} + +static inline int __fscrypt_encrypt_symlink(struct inode *inode, + const char *target, + unsigned int len, + struct fscrypt_str *disk_link) +{ + return -EOPNOTSUPP; +} + +static inline const char *fscrypt_get_symlink(struct inode *inode, + const void *caddr, + unsigned int max_size, + struct delayed_call *done) +{ + return ERR_PTR(-EOPNOTSUPP); +} + #endif /* _LINUX_FSCRYPT_NOTSUPP_H */ diff --git a/include/linux/fscrypt_supp.h b/include/linux/fscrypt_supp.h index cf9e9fc02f0a..477a7a6504d2 100644 --- a/include/linux/fscrypt_supp.h +++ b/include/linux/fscrypt_supp.h @@ -11,8 +11,54 @@ #ifndef _LINUX_FSCRYPT_SUPP_H #define _LINUX_FSCRYPT_SUPP_H +#include <linux/mm.h> +#include <linux/slab.h> + +/* + * fscrypt superblock flags + */ +#define FS_CFLG_OWN_PAGES (1U << 1) + +/* + * crypto operations for filesystems + */ +struct fscrypt_operations { + unsigned int flags; + const char *key_prefix; + int (*get_context)(struct inode *, void *, size_t); + int (*set_context)(struct inode *, const void *, size_t, void *); + bool (*dummy_context)(struct inode *); + bool (*empty_dir)(struct inode *); + unsigned (*max_namelen)(struct inode *); +}; + +struct fscrypt_ctx { + union { + struct { + struct page *bounce_page; /* Ciphertext page */ + struct page *control_page; /* Original page */ + } w; + struct { + struct bio *bio; + struct work_struct work; + } r; + struct list_head free_list; /* Free list */ + }; + u8 flags; /* Flags */ +}; + +static inline bool fscrypt_has_encryption_key(const struct inode *inode) +{ + return (inode->i_crypt_info != NULL); +} + +static inline bool fscrypt_dummy_context_enabled(struct inode *inode) +{ + return inode->i_sb->s_cop->dummy_context && + inode->i_sb->s_cop->dummy_context(inode); +} + /* crypto.c */ -extern struct kmem_cache *fscrypt_info_cachep; extern struct fscrypt_ctx *fscrypt_get_ctx(const struct inode *, gfp_t); extern void fscrypt_release_ctx(struct fscrypt_ctx *); extern struct page *fscrypt_encrypt_page(const struct inode *, struct page *, @@ -20,6 +66,12 @@ extern struct page *fscrypt_encrypt_page(const struct inode *, struct page *, u64, gfp_t); extern int fscrypt_decrypt_page(const struct inode *, struct page *, unsigned int, unsigned int, u64); + +static inline struct page *fscrypt_control_page(struct page *page) +{ + return ((struct fscrypt_ctx *)page_private(page))->w.control_page; +} + extern void fscrypt_restore_control_page(struct page *); extern const struct dentry_operations fscrypt_d_ops; @@ -44,7 +96,7 @@ extern int fscrypt_inherit_context(struct inode *, struct inode *, void *, bool); /* keyinfo.c */ extern int fscrypt_get_encryption_info(struct inode *); -extern void fscrypt_put_encryption_info(struct inode *, struct fscrypt_info *); +extern void fscrypt_put_encryption_info(struct inode *); /* fname.c */ extern int fscrypt_setup_filename(struct inode *, const struct qstr *, @@ -55,14 +107,11 @@ static inline void fscrypt_free_filename(struct fscrypt_name *fname) kfree(fname->crypto_buf.name); } -extern u32 fscrypt_fname_encrypted_size(const struct inode *, u32); extern int fscrypt_fname_alloc_buffer(const struct inode *, u32, struct fscrypt_str *); extern void fscrypt_fname_free_buffer(struct fscrypt_str *); extern int fscrypt_fname_disk_to_usr(struct inode *, u32, u32, const struct fscrypt_str *, struct fscrypt_str *); -extern int fscrypt_fname_usr_to_disk(struct inode *, const struct qstr *, - struct fscrypt_str *); #define FSCRYPT_FNAME_MAX_UNDIGESTED_SIZE 32 @@ -153,5 +202,14 @@ extern int __fscrypt_prepare_rename(struct inode *old_dir, struct dentry *new_dentry, unsigned int flags); extern int __fscrypt_prepare_lookup(struct inode *dir, struct dentry *dentry); +extern int __fscrypt_prepare_symlink(struct inode *dir, unsigned int len, + unsigned int max_len, + struct fscrypt_str *disk_link); +extern int __fscrypt_encrypt_symlink(struct inode *inode, const char *target, + unsigned int len, + struct fscrypt_str *disk_link); +extern const char *fscrypt_get_symlink(struct inode *inode, const void *caddr, + unsigned int max_size, + struct delayed_call *done); #endif /* _LINUX_FSCRYPT_SUPP_H */ |