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Diffstat (limited to 'fs/crypto/keysetup.c')
-rw-r--r--fs/crypto/keysetup.c86
1 files changed, 68 insertions, 18 deletions
diff --git a/fs/crypto/keysetup.c b/fs/crypto/keysetup.c
index b4fe01ea4bd4..4f3b9ecbfe4e 100644
--- a/fs/crypto/keysetup.c
+++ b/fs/crypto/keysetup.c
@@ -9,6 +9,7 @@
*/
#include <crypto/skcipher.h>
+#include <linux/export.h>
#include <linux/random.h>
#include "fscrypt_private.h"
@@ -96,14 +97,15 @@ select_encryption_mode(const union fscrypt_policy *policy,
}
/* Create a symmetric cipher object for the given encryption mode and key */
-static struct crypto_skcipher *
+static struct crypto_sync_skcipher *
fscrypt_allocate_skcipher(struct fscrypt_mode *mode, const u8 *raw_key,
const struct inode *inode)
{
- struct crypto_skcipher *tfm;
+ struct crypto_sync_skcipher *tfm;
int err;
- tfm = crypto_alloc_skcipher(mode->cipher_str, 0, 0);
+ tfm = crypto_alloc_sync_skcipher(mode->cipher_str, 0,
+ FSCRYPT_CRYPTOAPI_MASK);
if (IS_ERR(tfm)) {
if (PTR_ERR(tfm) == -ENOENT) {
fscrypt_warn(inode,
@@ -123,21 +125,22 @@ fscrypt_allocate_skcipher(struct fscrypt_mode *mode, const u8 *raw_key,
* first time a mode is used.
*/
pr_info("fscrypt: %s using implementation \"%s\"\n",
- mode->friendly_name, crypto_skcipher_driver_name(tfm));
+ mode->friendly_name,
+ crypto_skcipher_driver_name(&tfm->base));
}
- if (WARN_ON_ONCE(crypto_skcipher_ivsize(tfm) != mode->ivsize)) {
+ if (WARN_ON_ONCE(crypto_sync_skcipher_ivsize(tfm) != mode->ivsize)) {
err = -EINVAL;
goto err_free_tfm;
}
- crypto_skcipher_set_flags(tfm, CRYPTO_TFM_REQ_FORBID_WEAK_KEYS);
- err = crypto_skcipher_setkey(tfm, raw_key, mode->keysize);
+ crypto_sync_skcipher_set_flags(tfm, CRYPTO_TFM_REQ_FORBID_WEAK_KEYS);
+ err = crypto_sync_skcipher_setkey(tfm, raw_key, mode->keysize);
if (err)
goto err_free_tfm;
return tfm;
err_free_tfm:
- crypto_free_skcipher(tfm);
+ crypto_free_sync_skcipher(tfm);
return ERR_PTR(err);
}
@@ -150,10 +153,12 @@ err_free_tfm:
int fscrypt_prepare_key(struct fscrypt_prepared_key *prep_key,
const u8 *raw_key, const struct fscrypt_inode_info *ci)
{
- struct crypto_skcipher *tfm;
+ struct crypto_sync_skcipher *tfm;
if (fscrypt_using_inline_encryption(ci))
- return fscrypt_prepare_inline_crypt_key(prep_key, raw_key, ci);
+ return fscrypt_prepare_inline_crypt_key(prep_key, raw_key,
+ ci->ci_mode->keysize,
+ false, ci);
tfm = fscrypt_allocate_skcipher(ci->ci_mode, raw_key, ci->ci_inode);
if (IS_ERR(tfm))
@@ -172,7 +177,7 @@ int fscrypt_prepare_key(struct fscrypt_prepared_key *prep_key,
void fscrypt_destroy_prepared_key(struct super_block *sb,
struct fscrypt_prepared_key *prep_key)
{
- crypto_free_skcipher(prep_key->tfm);
+ crypto_free_sync_skcipher(prep_key->tfm);
fscrypt_destroy_inline_crypt_key(sb, prep_key);
memzero_explicit(prep_key, sizeof(*prep_key));
}
@@ -195,14 +200,29 @@ static int setup_per_mode_enc_key(struct fscrypt_inode_info *ci,
struct fscrypt_mode *mode = ci->ci_mode;
const u8 mode_num = mode - fscrypt_modes;
struct fscrypt_prepared_key *prep_key;
- u8 mode_key[FSCRYPT_MAX_KEY_SIZE];
+ u8 mode_key[FSCRYPT_MAX_RAW_KEY_SIZE];
u8 hkdf_info[sizeof(mode_num) + sizeof(sb->s_uuid)];
unsigned int hkdf_infolen = 0;
+ bool use_hw_wrapped_key = false;
int err;
if (WARN_ON_ONCE(mode_num > FSCRYPT_MODE_MAX))
return -EINVAL;
+ if (mk->mk_secret.is_hw_wrapped && S_ISREG(inode->i_mode)) {
+ /* Using a hardware-wrapped key for file contents encryption */
+ if (!fscrypt_using_inline_encryption(ci)) {
+ if (sb->s_flags & SB_INLINECRYPT)
+ fscrypt_warn(ci->ci_inode,
+ "Hardware-wrapped key required, but no suitable inline encryption capabilities are available");
+ else
+ fscrypt_warn(ci->ci_inode,
+ "Hardware-wrapped keys require inline encryption (-o inlinecrypt)");
+ return -EINVAL;
+ }
+ use_hw_wrapped_key = true;
+ }
+
prep_key = &keys[mode_num];
if (fscrypt_is_key_prepared(prep_key, ci)) {
ci->ci_enc_key = *prep_key;
@@ -214,6 +234,16 @@ static int setup_per_mode_enc_key(struct fscrypt_inode_info *ci,
if (fscrypt_is_key_prepared(prep_key, ci))
goto done_unlock;
+ if (use_hw_wrapped_key) {
+ err = fscrypt_prepare_inline_crypt_key(prep_key,
+ mk->mk_secret.bytes,
+ mk->mk_secret.size, true,
+ ci);
+ if (err)
+ goto out_unlock;
+ goto done_unlock;
+ }
+
BUILD_BUG_ON(sizeof(mode_num) != 1);
BUILD_BUG_ON(sizeof(sb->s_uuid) != 16);
BUILD_BUG_ON(sizeof(hkdf_info) != 17);
@@ -336,6 +366,14 @@ static int fscrypt_setup_v2_file_key(struct fscrypt_inode_info *ci,
{
int err;
+ if (mk->mk_secret.is_hw_wrapped &&
+ !(ci->ci_policy.v2.flags & (FSCRYPT_POLICY_FLAG_IV_INO_LBLK_64 |
+ FSCRYPT_POLICY_FLAG_IV_INO_LBLK_32))) {
+ fscrypt_warn(ci->ci_inode,
+ "Hardware-wrapped keys are only supported with IV_INO_LBLK policies");
+ return -EINVAL;
+ }
+
if (ci->ci_policy.v2.flags & FSCRYPT_POLICY_FLAG_DIRECT_KEY) {
/*
* DIRECT_KEY: instead of deriving per-file encryption keys, the
@@ -362,7 +400,7 @@ static int fscrypt_setup_v2_file_key(struct fscrypt_inode_info *ci,
FSCRYPT_POLICY_FLAG_IV_INO_LBLK_32) {
err = fscrypt_setup_iv_ino_lblk_32_key(ci, mk);
} else {
- u8 derived_key[FSCRYPT_MAX_KEY_SIZE];
+ u8 derived_key[FSCRYPT_MAX_RAW_KEY_SIZE];
err = fscrypt_hkdf_expand(&mk->mk_secret.hkdf,
HKDF_CONTEXT_PER_FILE_ENC_KEY,
@@ -445,10 +483,6 @@ static int setup_file_encryption_key(struct fscrypt_inode_info *ci,
struct fscrypt_master_key *mk;
int err;
- err = fscrypt_select_encryption_impl(ci);
- if (err)
- return err;
-
err = fscrypt_policy_to_key_spec(&ci->ci_policy, &mk_spec);
if (err)
return err;
@@ -476,6 +510,10 @@ static int setup_file_encryption_key(struct fscrypt_inode_info *ci,
if (ci->ci_policy.version != FSCRYPT_POLICY_V1)
return -ENOKEY;
+ err = fscrypt_select_encryption_impl(ci, false);
+ if (err)
+ return err;
+
/*
* As a legacy fallback for v1 policies, search for the key in
* the current task's subscribed keyrings too. Don't move this
@@ -497,9 +535,21 @@ static int setup_file_encryption_key(struct fscrypt_inode_info *ci,
goto out_release_key;
}
+ err = fscrypt_select_encryption_impl(ci, mk->mk_secret.is_hw_wrapped);
+ if (err)
+ goto out_release_key;
+
switch (ci->ci_policy.version) {
case FSCRYPT_POLICY_V1:
- err = fscrypt_setup_v1_file_key(ci, mk->mk_secret.raw);
+ if (WARN_ON_ONCE(mk->mk_secret.is_hw_wrapped)) {
+ /*
+ * This should never happen, as adding a v1 policy key
+ * that is hardware-wrapped isn't allowed.
+ */
+ err = -EINVAL;
+ goto out_release_key;
+ }
+ err = fscrypt_setup_v1_file_key(ci, mk->mk_secret.bytes);
break;
case FSCRYPT_POLICY_V2:
err = fscrypt_setup_v2_file_key(ci, mk, need_dirhash_key);
generated by cgit (git 2.34.1) at 2025-08-05 18:44:00 +0000