diff --git a/fs/f2fs/crypto.c b/fs/f2fs/crypto.c index c6d11229aee4d2fcca7bfcc47ecbde2307cce0ba..2c7819aebcc5e4057345a7bf511480fb4b53b3d5 100644 --- a/fs/f2fs/crypto.c +++ b/fs/f2fs/crypto.c @@ -91,8 +91,6 @@ void f2fs_release_crypto_ctx(struct f2fs_crypto_ctx *ctx) } ctx->w.control_page = NULL; if (ctx->flags & F2FS_CTX_REQUIRES_FREE_ENCRYPT_FL) { - if (ctx->tfm) - crypto_free_tfm(ctx->tfm); kmem_cache_free(f2fs_crypto_ctx_cachep, ctx); } else { spin_lock_irqsave(&f2fs_crypto_ctx_lock, flags); @@ -113,7 +111,6 @@ void f2fs_release_crypto_ctx(struct f2fs_crypto_ctx *ctx) struct f2fs_crypto_ctx *f2fs_get_crypto_ctx(struct inode *inode) { struct f2fs_crypto_ctx *ctx = NULL; - int res = 0; unsigned long flags; struct f2fs_crypt_info *ci = F2FS_I(inode)->i_crypt_info; @@ -138,56 +135,13 @@ struct f2fs_crypto_ctx *f2fs_get_crypto_ctx(struct inode *inode) spin_unlock_irqrestore(&f2fs_crypto_ctx_lock, flags); if (!ctx) { ctx = kmem_cache_zalloc(f2fs_crypto_ctx_cachep, GFP_NOFS); - if (!ctx) { - res = -ENOMEM; - goto out; - } + if (!ctx) + return ERR_PTR(-ENOMEM); ctx->flags |= F2FS_CTX_REQUIRES_FREE_ENCRYPT_FL; } else { ctx->flags &= ~F2FS_CTX_REQUIRES_FREE_ENCRYPT_FL; } ctx->flags &= ~F2FS_WRITE_PATH_FL; - - /* - * Allocate a new Crypto API context if we don't already have - * one or if it isn't the right mode. - */ - if (ctx->tfm && (ctx->mode != ci->ci_data_mode)) { - crypto_free_tfm(ctx->tfm); - ctx->tfm = NULL; - ctx->mode = F2FS_ENCRYPTION_MODE_INVALID; - } - if (!ctx->tfm) { - switch (ci->ci_data_mode) { - case F2FS_ENCRYPTION_MODE_AES_256_XTS: - ctx->tfm = crypto_ablkcipher_tfm( - crypto_alloc_ablkcipher("xts(aes)", 0, 0)); - break; - case F2FS_ENCRYPTION_MODE_AES_256_GCM: - /* - * TODO(mhalcrow): AEAD w/ gcm(aes); - * crypto_aead_setauthsize() - */ - ctx->tfm = ERR_PTR(-ENOTSUPP); - break; - default: - BUG(); - } - if (IS_ERR_OR_NULL(ctx->tfm)) { - res = PTR_ERR(ctx->tfm); - ctx->tfm = NULL; - goto out; - } - ctx->mode = ci->ci_data_mode; - } - BUG_ON(ci->ci_size != f2fs_encryption_key_size(ci->ci_data_mode)); - -out: - if (res) { - if (!IS_ERR_OR_NULL(ctx)) - f2fs_release_crypto_ctx(ctx); - ctx = ERR_PTR(res); - } return ctx; } @@ -229,11 +183,8 @@ static void f2fs_crypto_destroy(void) { struct f2fs_crypto_ctx *pos, *n; - list_for_each_entry_safe(pos, n, &f2fs_free_crypto_ctxs, free_list) { - if (pos->tfm) - crypto_free_tfm(pos->tfm); + list_for_each_entry_safe(pos, n, &f2fs_free_crypto_ctxs, free_list) kmem_cache_free(f2fs_crypto_ctx_cachep, pos); - } INIT_LIST_HEAD(&f2fs_free_crypto_ctxs); if (f2fs_bounce_page_pool) mempool_destroy(f2fs_bounce_page_pool); @@ -383,32 +334,11 @@ static int f2fs_page_crypto(struct f2fs_crypto_ctx *ctx, struct ablkcipher_request *req = NULL; DECLARE_F2FS_COMPLETION_RESULT(ecr); struct scatterlist dst, src; - struct f2fs_inode_info *fi = F2FS_I(inode); - struct crypto_ablkcipher *atfm = __crypto_ablkcipher_cast(ctx->tfm); + struct f2fs_crypt_info *ci = F2FS_I(inode)->i_crypt_info; + struct crypto_ablkcipher *tfm = ci->ci_ctfm; int res = 0; - BUG_ON(!ctx->tfm); - BUG_ON(ctx->mode != fi->i_crypt_info->ci_data_mode); - - if (ctx->mode != F2FS_ENCRYPTION_MODE_AES_256_XTS) { - printk_ratelimited(KERN_ERR - "%s: unsupported crypto algorithm: %d\n", - __func__, ctx->mode); - return -ENOTSUPP; - } - - crypto_ablkcipher_clear_flags(atfm, ~0); - crypto_tfm_set_flags(ctx->tfm, CRYPTO_TFM_REQ_WEAK_KEY); - - res = crypto_ablkcipher_setkey(atfm, fi->i_crypt_info->ci_raw, - fi->i_crypt_info->ci_size); - if (res) { - printk_ratelimited(KERN_ERR - "%s: crypto_ablkcipher_setkey() failed\n", - __func__); - return res; - } - req = ablkcipher_request_alloc(atfm, GFP_NOFS); + req = ablkcipher_request_alloc(tfm, GFP_NOFS); if (!req) { printk_ratelimited(KERN_ERR "%s: crypto_request_alloc() failed\n", diff --git a/fs/f2fs/crypto_fname.c b/fs/f2fs/crypto_fname.c index 016c4b63b53d879a3537e7542c44b04818df315a..81852cca7bbe395eebad0a017abe91317b6f67e4 100644 --- a/fs/f2fs/crypto_fname.c +++ b/fs/f2fs/crypto_fname.c @@ -249,52 +249,6 @@ static int digest_decode(const char *src, int len, char *dst) return cp - dst; } -int f2fs_setup_fname_crypto(struct inode *inode) -{ - struct f2fs_inode_info *fi = F2FS_I(inode); - struct f2fs_crypt_info *ci = fi->i_crypt_info; - struct crypto_ablkcipher *ctfm; - int res; - - /* Check if the crypto policy is set on the inode */ - res = f2fs_encrypted_inode(inode); - if (res == 0) - return 0; - - res = f2fs_get_encryption_info(inode); - if (res < 0) - return res; - ci = fi->i_crypt_info; - - if (!ci || ci->ci_ctfm) - return 0; - - if (ci->ci_filename_mode != F2FS_ENCRYPTION_MODE_AES_256_CTS) { - printk_once(KERN_WARNING "f2fs: unsupported key mode %d\n", - ci->ci_filename_mode); - return -ENOKEY; - } - - ctfm = crypto_alloc_ablkcipher("cts(cbc(aes))", 0, 0); - if (!ctfm || IS_ERR(ctfm)) { - res = ctfm ? PTR_ERR(ctfm) : -ENOMEM; - printk(KERN_DEBUG "%s: error (%d) allocating crypto tfm\n", - __func__, res); - return res; - } - crypto_ablkcipher_clear_flags(ctfm, ~0); - crypto_tfm_set_flags(crypto_ablkcipher_tfm(ctfm), - CRYPTO_TFM_REQ_WEAK_KEY); - - res = crypto_ablkcipher_setkey(ctfm, ci->ci_raw, ci->ci_size); - if (res) { - crypto_free_ablkcipher(ctfm); - return -EIO; - } - ci->ci_ctfm = ctfm; - return 0; -} - /** * f2fs_fname_crypto_round_up() - * @@ -427,7 +381,7 @@ int f2fs_fname_setup_filename(struct inode *dir, const struct qstr *iname, fname->disk_name.len = iname->len; return 0; } - ret = f2fs_setup_fname_crypto(dir); + ret = f2fs_get_encryption_info(dir); if (ret) return ret; ci = F2FS_I(dir)->i_crypt_info; diff --git a/fs/f2fs/crypto_key.c b/fs/f2fs/crypto_key.c index 8a10569a8b7cddaa9c82c22c8b7886d10fec5c68..95b8f936f00b647086b4d8bb61b36295d2e915cc 100644 --- a/fs/f2fs/crypto_key.c +++ b/fs/f2fs/crypto_key.c @@ -87,20 +87,31 @@ static int f2fs_derive_key_aes(char deriving_key[F2FS_AES_128_ECB_KEY_SIZE], return res; } -void f2fs_free_encryption_info(struct inode *inode) +static void f2fs_free_crypt_info(struct f2fs_crypt_info *ci) { - struct f2fs_inode_info *fi = F2FS_I(inode); - struct f2fs_crypt_info *ci = fi->i_crypt_info; - if (!ci) return; if (ci->ci_keyring_key) key_put(ci->ci_keyring_key); crypto_free_ablkcipher(ci->ci_ctfm); - memzero_explicit(&ci->ci_raw, sizeof(ci->ci_raw)); kmem_cache_free(f2fs_crypt_info_cachep, ci); - fi->i_crypt_info = NULL; +} + +void f2fs_free_encryption_info(struct inode *inode, struct f2fs_crypt_info *ci) +{ + struct f2fs_inode_info *fi = F2FS_I(inode); + struct f2fs_crypt_info *prev; + + if (ci == NULL) + ci = ACCESS_ONCE(fi->i_crypt_info); + if (ci == NULL) + return; + prev = cmpxchg(&fi->i_crypt_info, ci, NULL); + if (prev != ci) + return; + + f2fs_free_crypt_info(ci); } int _f2fs_get_encryption_info(struct inode *inode) @@ -113,17 +124,23 @@ int _f2fs_get_encryption_info(struct inode *inode) struct f2fs_encryption_key *master_key; struct f2fs_encryption_context ctx; struct user_key_payload *ukp; + struct crypto_ablkcipher *ctfm; + const char *cipher_str; + char raw_key[F2FS_MAX_KEY_SIZE]; + char mode; int res; res = f2fs_crypto_initialize(); if (res) return res; - - if (fi->i_crypt_info) { - if (!fi->i_crypt_info->ci_keyring_key || - key_validate(fi->i_crypt_info->ci_keyring_key) == 0) +retry: + crypt_info = ACCESS_ONCE(fi->i_crypt_info); + if (crypt_info) { + if (!crypt_info->ci_keyring_key || + key_validate(crypt_info->ci_keyring_key) == 0) return 0; - f2fs_free_encryption_info(inode); + f2fs_free_encryption_info(inode, crypt_info); + goto retry; } res = f2fs_getxattr(inode, F2FS_XATTR_INDEX_ENCRYPTION, @@ -143,18 +160,30 @@ int _f2fs_get_encryption_info(struct inode *inode) crypt_info->ci_data_mode = ctx.contents_encryption_mode; crypt_info->ci_filename_mode = ctx.filenames_encryption_mode; crypt_info->ci_ctfm = NULL; + crypt_info->ci_keyring_key = NULL; memcpy(crypt_info->ci_master_key, ctx.master_key_descriptor, sizeof(crypt_info->ci_master_key)); if (S_ISREG(inode->i_mode)) - crypt_info->ci_size = - f2fs_encryption_key_size(crypt_info->ci_data_mode); + mode = crypt_info->ci_data_mode; else if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) - crypt_info->ci_size = - f2fs_encryption_key_size(crypt_info->ci_filename_mode); + mode = crypt_info->ci_filename_mode; else BUG(); - BUG_ON(!crypt_info->ci_size); + switch (mode) { + case F2FS_ENCRYPTION_MODE_AES_256_XTS: + cipher_str = "xts(aes)"; + break; + case F2FS_ENCRYPTION_MODE_AES_256_CTS: + cipher_str = "cts(cbc(aes))"; + break; + default: + printk_once(KERN_WARNING + "f2fs: unsupported key mode %d (ino %u)\n", + mode, (unsigned) inode->i_ino); + res = -ENOKEY; + goto out; + } memcpy(full_key_descriptor, F2FS_KEY_DESC_PREFIX, F2FS_KEY_DESC_PREFIX_SIZE); @@ -169,6 +198,7 @@ int _f2fs_get_encryption_info(struct inode *inode) keyring_key = NULL; goto out; } + crypt_info->ci_keyring_key = keyring_key; BUG_ON(keyring_key->type != &key_type_logon); ukp = ((struct user_key_payload *)keyring_key->payload.data); if (ukp->datalen != sizeof(struct f2fs_encryption_key)) { @@ -180,19 +210,40 @@ int _f2fs_get_encryption_info(struct inode *inode) F2FS_KEY_DERIVATION_NONCE_SIZE); BUG_ON(master_key->size != F2FS_AES_256_XTS_KEY_SIZE); res = f2fs_derive_key_aes(ctx.nonce, master_key->raw, - crypt_info->ci_raw); -out: - if (res < 0) { - if (res == -ENOKEY) - res = 0; - kmem_cache_free(f2fs_crypt_info_cachep, crypt_info); - } else { - fi->i_crypt_info = crypt_info; - crypt_info->ci_keyring_key = keyring_key; - keyring_key = NULL; + raw_key); + if (res) + goto out; + + ctfm = crypto_alloc_ablkcipher(cipher_str, 0, 0); + if (!ctfm || IS_ERR(ctfm)) { + res = ctfm ? PTR_ERR(ctfm) : -ENOMEM; + printk(KERN_DEBUG + "%s: error %d (inode %u) allocating crypto tfm\n", + __func__, res, (unsigned) inode->i_ino); + goto out; } - if (keyring_key) - key_put(keyring_key); + crypt_info->ci_ctfm = ctfm; + crypto_ablkcipher_clear_flags(ctfm, ~0); + crypto_tfm_set_flags(crypto_ablkcipher_tfm(ctfm), + CRYPTO_TFM_REQ_WEAK_KEY); + res = crypto_ablkcipher_setkey(ctfm, raw_key, + f2fs_encryption_key_size(mode)); + if (res) + goto out; + + memzero_explicit(raw_key, sizeof(raw_key)); + if (cmpxchg(&fi->i_crypt_info, NULL, crypt_info) != NULL) { + f2fs_free_crypt_info(crypt_info); + goto retry; + } + return 0; + +out: + if (res == -ENOKEY && !S_ISREG(inode->i_mode)) + res = 0; + + f2fs_free_crypt_info(crypt_info); + memzero_explicit(raw_key, sizeof(raw_key)); return res; } diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c index 3e923763daca0c44af75600de599babaf6839bc2..a34ebd8312ab89e703cfe85a3820072b4d06c083 100644 --- a/fs/f2fs/dir.c +++ b/fs/f2fs/dir.c @@ -825,11 +825,11 @@ static int f2fs_readdir(struct file *file, struct dir_context *ctx) struct f2fs_str fstr = FSTR_INIT(NULL, 0); int err = 0; - err = f2fs_setup_fname_crypto(inode); - if (err) - return err; - if (f2fs_encrypted_inode(inode)) { + err = f2fs_get_encryption_info(inode); + if (err) + return err; + err = f2fs_fname_crypto_alloc_buffer(inode, F2FS_NAME_LEN, &fstr); if (err < 0) diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 7e93fcf2df788b33480c513a305d3599b8ab8074..70cdf7b81e806727bdb3021ba1e51fabb4733c67 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -2016,7 +2016,7 @@ int f2fs_decrypt_one(struct inode *, struct page *); void f2fs_end_io_crypto_work(struct f2fs_crypto_ctx *, struct bio *); /* crypto_key.c */ -void f2fs_free_encryption_info(struct inode *); +void f2fs_free_encryption_info(struct inode *, struct f2fs_crypt_info *); int _f2fs_get_encryption_info(struct inode *inode); /* crypto_fname.c */ @@ -2051,7 +2051,6 @@ static inline int f2fs_get_encryption_info(struct inode *inode) return 0; } -int f2fs_setup_fname_crypto(struct inode *); void f2fs_fname_crypto_free_buffer(struct f2fs_str *); int f2fs_fname_setup_filename(struct inode *, const struct qstr *, int lookup, struct f2fs_filename *); @@ -2065,8 +2064,6 @@ static inline void f2fs_exit_crypto(void) { } static inline int f2fs_has_encryption_key(struct inode *i) { return 0; } static inline int f2fs_get_encryption_info(struct inode *i) { return 0; } - -static inline int f2fs_setup_fname_crypto(struct inode *i) { return 0; } static inline void f2fs_fname_crypto_free_buffer(struct f2fs_str *p) { } static inline int f2fs_fname_setup_filename(struct inode *dir, diff --git a/fs/f2fs/f2fs_crypto.h b/fs/f2fs/f2fs_crypto.h index e33cec9c3f3612c76a30f39e90d829c63f9edda6..be59d91928fdecd72bec88d99e52ef0ca3771157 100644 --- a/fs/f2fs/f2fs_crypto.h +++ b/fs/f2fs/f2fs_crypto.h @@ -75,13 +75,11 @@ struct f2fs_encryption_key { } __attribute__((__packed__)); struct f2fs_crypt_info { - unsigned char ci_size; char ci_data_mode; char ci_filename_mode; char ci_flags; struct crypto_ablkcipher *ci_ctfm; struct key *ci_keyring_key; - char ci_raw[F2FS_MAX_KEY_SIZE]; char ci_master_key[F2FS_KEY_DESCRIPTOR_SIZE]; }; @@ -90,7 +88,6 @@ struct f2fs_crypt_info { #define F2FS_WRITE_PATH_FL 0x00000004 struct f2fs_crypto_ctx { - struct crypto_tfm *tfm; /* Crypto API context */ union { struct { struct page *bounce_page; /* Ciphertext page */ @@ -103,7 +100,6 @@ struct f2fs_crypto_ctx { struct list_head free_list; /* Free list */ }; char flags; /* Flags */ - char mode; /* Encryption mode for tfm */ }; struct f2fs_completion_result { diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c index ea6ba3bc84725e9909cba51f64ae9c758280ef75..2550868dc651eefe3ed3f1643f9af47a777cdeb9 100644 --- a/fs/f2fs/inode.c +++ b/fs/f2fs/inode.c @@ -364,7 +364,7 @@ void f2fs_evict_inode(struct inode *inode) out_clear: #ifdef CONFIG_F2FS_FS_ENCRYPTION if (F2FS_I(inode)->i_crypt_info) - f2fs_free_encryption_info(inode); + f2fs_free_encryption_info(inode, F2FS_I(inode)->i_crypt_info); #endif clear_inode(inode); } diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c index a316783de8c9ca0a3e47a7e103870c67fcb4ef67..55d0d27dfdf2067b725070b14068849b21244323 100644 --- a/fs/f2fs/namei.c +++ b/fs/f2fs/namei.c @@ -364,7 +364,7 @@ static int f2fs_symlink(struct inode *dir, struct dentry *dentry, if (err) goto err_out; - err = f2fs_setup_fname_crypto(inode); + err = f2fs_get_encryption_info(inode); if (err) goto err_out; @@ -929,7 +929,7 @@ static void *f2fs_encrypted_follow_link(struct dentry *dentry, u32 max_size = inode->i_sb->s_blocksize; int res; - res = f2fs_setup_fname_crypto(inode); + res = f2fs_get_encryption_info(inode); if (res) return ERR_PTR(res); diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index d4cd04dc3314979251d3e058ceb1a8c354bede95..8b5f5fb8f5cb4e1d0e7c3487e90396b7ac08a558 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -449,7 +449,8 @@ static int f2fs_drop_inode(struct inode *inode) #ifdef CONFIG_F2FS_FS_ENCRYPTION if (F2FS_I(inode)->i_crypt_info) - f2fs_free_encryption_info(inode); + f2fs_free_encryption_info(inode, + F2FS_I(inode)->i_crypt_info); #endif spin_lock(&inode->i_lock); }