From 670027c507e99521d416994a18a498def9ef2ea3 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Fabian=20Silva=20Delgado?= Date: Sat, 22 Oct 2016 19:31:08 -0300 Subject: Linux-libre 4.8.3-gnu --- fs/ext4/crypto_key.c | 274 --------------------------------------------------- 1 file changed, 274 deletions(-) delete mode 100644 fs/ext4/crypto_key.c (limited to 'fs/ext4/crypto_key.c') diff --git a/fs/ext4/crypto_key.c b/fs/ext4/crypto_key.c deleted file mode 100644 index 0129d688d..000000000 --- a/fs/ext4/crypto_key.c +++ /dev/null @@ -1,274 +0,0 @@ -/* - * linux/fs/ext4/crypto_key.c - * - * Copyright (C) 2015, Google, Inc. - * - * This contains encryption key functions for ext4 - * - * Written by Michael Halcrow, Ildar Muslukhov, and Uday Savagaonkar, 2015. - */ - -#include -#include -#include -#include -#include -#include - -#include "ext4.h" -#include "xattr.h" - -static void derive_crypt_complete(struct crypto_async_request *req, int rc) -{ - struct ext4_completion_result *ecr = req->data; - - if (rc == -EINPROGRESS) - return; - - ecr->res = rc; - complete(&ecr->completion); -} - -/** - * ext4_derive_key_aes() - Derive a key using AES-128-ECB - * @deriving_key: Encryption key used for derivation. - * @source_key: Source key to which to apply derivation. - * @derived_key: Derived key. - * - * Return: Zero on success; non-zero otherwise. - */ -static int ext4_derive_key_aes(char deriving_key[EXT4_AES_128_ECB_KEY_SIZE], - char source_key[EXT4_AES_256_XTS_KEY_SIZE], - char derived_key[EXT4_AES_256_XTS_KEY_SIZE]) -{ - int res = 0; - struct skcipher_request *req = NULL; - DECLARE_EXT4_COMPLETION_RESULT(ecr); - struct scatterlist src_sg, dst_sg; - struct crypto_skcipher *tfm = crypto_alloc_skcipher("ecb(aes)", 0, 0); - - if (IS_ERR(tfm)) { - res = PTR_ERR(tfm); - tfm = NULL; - goto out; - } - crypto_skcipher_set_flags(tfm, CRYPTO_TFM_REQ_WEAK_KEY); - req = skcipher_request_alloc(tfm, GFP_NOFS); - if (!req) { - res = -ENOMEM; - goto out; - } - skcipher_request_set_callback(req, - CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP, - derive_crypt_complete, &ecr); - res = crypto_skcipher_setkey(tfm, deriving_key, - EXT4_AES_128_ECB_KEY_SIZE); - if (res < 0) - goto out; - sg_init_one(&src_sg, source_key, EXT4_AES_256_XTS_KEY_SIZE); - sg_init_one(&dst_sg, derived_key, EXT4_AES_256_XTS_KEY_SIZE); - skcipher_request_set_crypt(req, &src_sg, &dst_sg, - EXT4_AES_256_XTS_KEY_SIZE, NULL); - res = crypto_skcipher_encrypt(req); - if (res == -EINPROGRESS || res == -EBUSY) { - wait_for_completion(&ecr.completion); - res = ecr.res; - } - -out: - skcipher_request_free(req); - crypto_free_skcipher(tfm); - return res; -} - -void ext4_free_crypt_info(struct ext4_crypt_info *ci) -{ - if (!ci) - return; - - if (ci->ci_keyring_key) - key_put(ci->ci_keyring_key); - crypto_free_skcipher(ci->ci_ctfm); - kmem_cache_free(ext4_crypt_info_cachep, ci); -} - -void ext4_free_encryption_info(struct inode *inode, - struct ext4_crypt_info *ci) -{ - struct ext4_inode_info *ei = EXT4_I(inode); - struct ext4_crypt_info *prev; - - if (ci == NULL) - ci = ACCESS_ONCE(ei->i_crypt_info); - if (ci == NULL) - return; - prev = cmpxchg(&ei->i_crypt_info, ci, NULL); - if (prev != ci) - return; - - ext4_free_crypt_info(ci); -} - -int _ext4_get_encryption_info(struct inode *inode) -{ - struct ext4_inode_info *ei = EXT4_I(inode); - struct ext4_crypt_info *crypt_info; - char full_key_descriptor[EXT4_KEY_DESC_PREFIX_SIZE + - (EXT4_KEY_DESCRIPTOR_SIZE * 2) + 1]; - struct key *keyring_key = NULL; - struct ext4_encryption_key *master_key; - struct ext4_encryption_context ctx; - const struct user_key_payload *ukp; - struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); - struct crypto_skcipher *ctfm; - const char *cipher_str; - char raw_key[EXT4_MAX_KEY_SIZE]; - char mode; - int res; - - if (!ext4_read_workqueue) { - res = ext4_init_crypto(); - if (res) - return res; - } - -retry: - crypt_info = ACCESS_ONCE(ei->i_crypt_info); - if (crypt_info) { - if (!crypt_info->ci_keyring_key || - key_validate(crypt_info->ci_keyring_key) == 0) - return 0; - ext4_free_encryption_info(inode, crypt_info); - goto retry; - } - - res = ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION, - EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, - &ctx, sizeof(ctx)); - if (res < 0) { - if (!DUMMY_ENCRYPTION_ENABLED(sbi)) - return res; - ctx.contents_encryption_mode = EXT4_ENCRYPTION_MODE_AES_256_XTS; - ctx.filenames_encryption_mode = - EXT4_ENCRYPTION_MODE_AES_256_CTS; - ctx.flags = 0; - } else if (res != sizeof(ctx)) - return -EINVAL; - res = 0; - - crypt_info = kmem_cache_alloc(ext4_crypt_info_cachep, GFP_KERNEL); - if (!crypt_info) - return -ENOMEM; - - crypt_info->ci_flags = ctx.flags; - 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)) - mode = crypt_info->ci_data_mode; - else if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) - mode = crypt_info->ci_filename_mode; - else - BUG(); - switch (mode) { - case EXT4_ENCRYPTION_MODE_AES_256_XTS: - cipher_str = "xts(aes)"; - break; - case EXT4_ENCRYPTION_MODE_AES_256_CTS: - cipher_str = "cts(cbc(aes))"; - break; - default: - printk_once(KERN_WARNING - "ext4: unsupported key mode %d (ino %u)\n", - mode, (unsigned) inode->i_ino); - res = -ENOKEY; - goto out; - } - if (DUMMY_ENCRYPTION_ENABLED(sbi)) { - memset(raw_key, 0x42, EXT4_AES_256_XTS_KEY_SIZE); - goto got_key; - } - memcpy(full_key_descriptor, EXT4_KEY_DESC_PREFIX, - EXT4_KEY_DESC_PREFIX_SIZE); - sprintf(full_key_descriptor + EXT4_KEY_DESC_PREFIX_SIZE, - "%*phN", EXT4_KEY_DESCRIPTOR_SIZE, - ctx.master_key_descriptor); - full_key_descriptor[EXT4_KEY_DESC_PREFIX_SIZE + - (2 * EXT4_KEY_DESCRIPTOR_SIZE)] = '\0'; - keyring_key = request_key(&key_type_logon, full_key_descriptor, NULL); - if (IS_ERR(keyring_key)) { - res = PTR_ERR(keyring_key); - keyring_key = NULL; - goto out; - } - crypt_info->ci_keyring_key = keyring_key; - if (keyring_key->type != &key_type_logon) { - printk_once(KERN_WARNING - "ext4: key type must be logon\n"); - res = -ENOKEY; - goto out; - } - down_read(&keyring_key->sem); - ukp = user_key_payload(keyring_key); - if (ukp->datalen != sizeof(struct ext4_encryption_key)) { - res = -EINVAL; - up_read(&keyring_key->sem); - goto out; - } - master_key = (struct ext4_encryption_key *)ukp->data; - BUILD_BUG_ON(EXT4_AES_128_ECB_KEY_SIZE != - EXT4_KEY_DERIVATION_NONCE_SIZE); - if (master_key->size != EXT4_AES_256_XTS_KEY_SIZE) { - printk_once(KERN_WARNING - "ext4: key size incorrect: %d\n", - master_key->size); - res = -ENOKEY; - up_read(&keyring_key->sem); - goto out; - } - res = ext4_derive_key_aes(ctx.nonce, master_key->raw, - raw_key); - up_read(&keyring_key->sem); - if (res) - goto out; -got_key: - ctfm = crypto_alloc_skcipher(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; - } - crypt_info->ci_ctfm = ctfm; - crypto_skcipher_clear_flags(ctfm, ~0); - crypto_tfm_set_flags(crypto_skcipher_tfm(ctfm), - CRYPTO_TFM_REQ_WEAK_KEY); - res = crypto_skcipher_setkey(ctfm, raw_key, - ext4_encryption_key_size(mode)); - if (res) - goto out; - memzero_explicit(raw_key, sizeof(raw_key)); - if (cmpxchg(&ei->i_crypt_info, NULL, crypt_info) != NULL) { - ext4_free_crypt_info(crypt_info); - goto retry; - } - return 0; - -out: - if (res == -ENOKEY) - res = 0; - ext4_free_crypt_info(crypt_info); - memzero_explicit(raw_key, sizeof(raw_key)); - return res; -} - -int ext4_has_encryption_key(struct inode *inode) -{ - struct ext4_inode_info *ei = EXT4_I(inode); - - return (ei->i_crypt_info != NULL); -} -- cgit v1.2.3