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Diffstat (limited to 'fs/f2fs/crypto_key.c')
-rw-r--r--fs/f2fs/crypto_key.c254
1 files changed, 0 insertions, 254 deletions
diff --git a/fs/f2fs/crypto_key.c b/fs/f2fs/crypto_key.c
deleted file mode 100644
index 5de2d866a..000000000
--- a/fs/f2fs/crypto_key.c
+++ /dev/null
@@ -1,254 +0,0 @@
-/*
- * linux/fs/f2fs/crypto_key.c
- *
- * Copied from linux/fs/f2fs/crypto_key.c
- *
- * Copyright (C) 2015, Google, Inc.
- *
- * This contains encryption key functions for f2fs
- *
- * Written by Michael Halcrow, Ildar Muslukhov, and Uday Savagaonkar, 2015.
- */
-#include <keys/encrypted-type.h>
-#include <keys/user-type.h>
-#include <linux/random.h>
-#include <linux/scatterlist.h>
-#include <uapi/linux/keyctl.h>
-#include <crypto/hash.h>
-#include <linux/f2fs_fs.h>
-
-#include "f2fs.h"
-#include "xattr.h"
-
-static void derive_crypt_complete(struct crypto_async_request *req, int rc)
-{
- struct f2fs_completion_result *ecr = req->data;
-
- if (rc == -EINPROGRESS)
- return;
-
- ecr->res = rc;
- complete(&ecr->completion);
-}
-
-/**
- * f2fs_derive_key_aes() - Derive a key using AES-128-ECB
- * @deriving_key: Encryption key used for derivatio.
- * @source_key: Source key to which to apply derivation.
- * @derived_key: Derived key.
- *
- * Return: Zero on success; non-zero otherwise.
- */
-static int f2fs_derive_key_aes(char deriving_key[F2FS_AES_128_ECB_KEY_SIZE],
- char source_key[F2FS_AES_256_XTS_KEY_SIZE],
- char derived_key[F2FS_AES_256_XTS_KEY_SIZE])
-{
- int res = 0;
- struct ablkcipher_request *req = NULL;
- DECLARE_F2FS_COMPLETION_RESULT(ecr);
- struct scatterlist src_sg, dst_sg;
- struct crypto_ablkcipher *tfm = crypto_alloc_ablkcipher("ecb(aes)", 0,
- 0);
-
- if (IS_ERR(tfm)) {
- res = PTR_ERR(tfm);
- tfm = NULL;
- goto out;
- }
- crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_REQ_WEAK_KEY);
- req = ablkcipher_request_alloc(tfm, GFP_NOFS);
- if (!req) {
- res = -ENOMEM;
- goto out;
- }
- ablkcipher_request_set_callback(req,
- CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
- derive_crypt_complete, &ecr);
- res = crypto_ablkcipher_setkey(tfm, deriving_key,
- F2FS_AES_128_ECB_KEY_SIZE);
- if (res < 0)
- goto out;
-
- sg_init_one(&src_sg, source_key, F2FS_AES_256_XTS_KEY_SIZE);
- sg_init_one(&dst_sg, derived_key, F2FS_AES_256_XTS_KEY_SIZE);
- ablkcipher_request_set_crypt(req, &src_sg, &dst_sg,
- F2FS_AES_256_XTS_KEY_SIZE, NULL);
- res = crypto_ablkcipher_encrypt(req);
- if (res == -EINPROGRESS || res == -EBUSY) {
- BUG_ON(req->base.data != &ecr);
- wait_for_completion(&ecr.completion);
- res = ecr.res;
- }
-out:
- if (req)
- ablkcipher_request_free(req);
- if (tfm)
- crypto_free_ablkcipher(tfm);
- return res;
-}
-
-static void f2fs_free_crypt_info(struct f2fs_crypt_info *ci)
-{
- if (!ci)
- return;
-
- key_put(ci->ci_keyring_key);
- crypto_free_ablkcipher(ci->ci_ctfm);
- kmem_cache_free(f2fs_crypt_info_cachep, ci);
-}
-
-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)
-{
- struct f2fs_inode_info *fi = F2FS_I(inode);
- struct f2fs_crypt_info *crypt_info;
- char full_key_descriptor[F2FS_KEY_DESC_PREFIX_SIZE +
- (F2FS_KEY_DESCRIPTOR_SIZE * 2) + 1];
- struct key *keyring_key = NULL;
- struct f2fs_encryption_key *master_key;
- struct f2fs_encryption_context ctx;
- const 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;
-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, crypt_info);
- goto retry;
- }
-
- res = f2fs_getxattr(inode, F2FS_XATTR_INDEX_ENCRYPTION,
- F2FS_XATTR_NAME_ENCRYPTION_CONTEXT,
- &ctx, sizeof(ctx), NULL);
- if (res < 0)
- return res;
- else if (res != sizeof(ctx))
- return -EINVAL;
- res = 0;
-
- crypt_info = kmem_cache_alloc(f2fs_crypt_info_cachep, GFP_NOFS);
- 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 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);
- sprintf(full_key_descriptor + F2FS_KEY_DESC_PREFIX_SIZE,
- "%*phN", F2FS_KEY_DESCRIPTOR_SIZE,
- ctx.master_key_descriptor);
- full_key_descriptor[F2FS_KEY_DESC_PREFIX_SIZE +
- (2 * F2FS_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;
- BUG_ON(keyring_key->type != &key_type_logon);
- ukp = user_key_payload(keyring_key);
- if (ukp->datalen != sizeof(struct f2fs_encryption_key)) {
- res = -EINVAL;
- goto out;
- }
- master_key = (struct f2fs_encryption_key *)ukp->data;
- BUILD_BUG_ON(F2FS_AES_128_ECB_KEY_SIZE !=
- 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,
- 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;
- }
- 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;
-}
-
-int f2fs_has_encryption_key(struct inode *inode)
-{
- struct f2fs_inode_info *fi = F2FS_I(inode);
-
- return (fi->i_crypt_info != NULL);
-}