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Diffstat (limited to 'fs/ext4/crypto_key.c')
-rw-r--r--fs/ext4/crypto_key.c98
1 files changed, 66 insertions, 32 deletions
diff --git a/fs/ext4/crypto_key.c b/fs/ext4/crypto_key.c
index 14ae7781f2a8..d3d6b28ce9b9 100644
--- a/fs/ext4/crypto_key.c
+++ b/fs/ext4/crypto_key.c
@@ -15,6 +15,7 @@
#include <uapi/linux/keyctl.h>
#include "ext4.h"
+#include "ext4_ice.h"
#include "xattr.h"
static void derive_crypt_complete(struct crypto_async_request *req, int rc)
@@ -173,6 +174,8 @@ 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_ablkcipher(ci->ci_ctfm);
kmem_cache_free(ext4_crypt_info_cachep, ci);
}
@@ -194,7 +197,13 @@ void ext4_free_encryption_info(struct inode *inode,
ext4_free_crypt_info(ci);
}
-int ext4_get_encryption_info(struct inode *inode)
+static int ext4_default_data_encryption_mode(void)
+{
+ return ext4_is_ice_enabled() ? EXT4_ENCRYPTION_MODE_PRIVATE :
+ EXT4_ENCRYPTION_MODE_AES_256_XTS;
+}
+
+int _ext4_get_encryption_info(struct inode *inode)
{
struct ext4_inode_info *ei = EXT4_I(inode);
struct ext4_crypt_info *crypt_info;
@@ -207,24 +216,32 @@ int ext4_get_encryption_info(struct inode *inode)
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
struct crypto_ablkcipher *ctfm;
const char *cipher_str;
- char raw_key[EXT4_MAX_KEY_SIZE];
- char mode;
+ int for_fname = 0;
+ int mode;
int res;
- if (ei->i_crypt_info)
- return 0;
-
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.contents_encryption_mode =
+ ext4_default_data_encryption_mode();
ctx.filenames_encryption_mode =
EXT4_ENCRYPTION_MODE_AES_256_CTS;
ctx.flags = 0;
@@ -240,14 +257,15 @@ int ext4_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))
- 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
+ if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
+ for_fname = 1;
+ else if (!S_ISREG(inode->i_mode))
BUG();
+ mode = for_fname ? crypt_info->ci_filename_mode :
+ crypt_info->ci_data_mode;
switch (mode) {
case EXT4_ENCRYPTION_MODE_AES_256_XTS:
cipher_str = "xts(aes)";
@@ -255,6 +273,8 @@ int ext4_get_encryption_info(struct inode *inode)
case EXT4_ENCRYPTION_MODE_AES_256_CTS:
cipher_str = "cts(cbc(aes))";
break;
+ case EXT4_ENCRYPTION_MODE_PRIVATE:
+ cipher_str = "bugon";
case EXT4_ENCRYPTION_MODE_AES_256_HEH:
cipher_str = "heh(aes)";
break;
@@ -266,7 +286,7 @@ int ext4_get_encryption_info(struct inode *inode)
goto out;
}
if (DUMMY_ENCRYPTION_ENABLED(sbi)) {
- memset(raw_key, 0x42, EXT4_AES_256_XTS_KEY_SIZE);
+ memset(crypt_info->ci_raw_key, 0x42, EXT4_AES_256_XTS_KEY_SIZE);
goto got_key;
}
memcpy(full_key_descriptor, EXT4_KEY_DESC_PREFIX,
@@ -282,6 +302,7 @@ int ext4_get_encryption_info(struct inode *inode)
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");
@@ -312,36 +333,49 @@ int ext4_get_encryption_info(struct inode *inode)
up_read(&keyring_key->sem);
goto out;
}
- res = ext4_derive_key(&ctx, master_key->raw, raw_key);
+ res = ext4_derive_key(&ctx, master_key->raw,
+ crypt_info->ci_raw_key);
up_read(&keyring_key->sem);
if (res)
goto out;
got_key:
- 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);
+ if (for_fname ||
+ (crypt_info->ci_data_mode != EXT4_ENCRYPTION_MODE_PRIVATE)) {
+ ctfm = crypto_alloc_ablkcipher(cipher_str, 0, 0);
+ if (!ctfm || IS_ERR(ctfm)) {
+ res = ctfm ? PTR_ERR(ctfm) : -ENOMEM;
+ pr_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, crypt_info->ci_raw_key,
+ ext4_encryption_key_size(mode));
+ if (res)
+ goto out;
+ memzero_explicit(crypt_info->ci_raw_key,
+ sizeof(crypt_info->ci_raw_key));
+ } else if (!ext4_is_ice_enabled()) {
+ pr_warn("%s: ICE support not available\n",
+ __func__);
+ res = -EINVAL;
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,
- ext4_encryption_key_size(mode));
- if (res)
- goto out;
+ if (cmpxchg(&ei->i_crypt_info, NULL, crypt_info) != NULL) {
+ ext4_free_crypt_info(crypt_info);
+ goto retry;
+ }
+ return 0;
- if (cmpxchg(&ei->i_crypt_info, NULL, crypt_info) == NULL)
- crypt_info = NULL;
out:
if (res == -ENOKEY)
res = 0;
- key_put(keyring_key);
+ memzero_explicit(crypt_info->ci_raw_key,
+ sizeof(crypt_info->ci_raw_key));
ext4_free_crypt_info(crypt_info);
- memzero_explicit(raw_key, sizeof(raw_key));
return res;
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-24 15:09:26 +0000