| Message ID | 20221122070632.21910-3-tianjia.zhang@linux.alibaba.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add SM4 XTS symmetric algorithm for blk-crypto and fscrypt | expand |
On Tue, Nov 22, 2022 at 03:06:32PM +0800, Tianjia Zhang wrote: > SM4 is a symmetric algorithm widely used in China, this patch enables > to use SM4-XTS mode to encrypt file content, and use SM4-CBC-CTS to > encrypt filename. > > Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com> There is still no explanation here about why you believe this algorithm is useful to support in fscrypt. - Eric
Hi Eric, On 11/23/22 3:22 AM, Eric Biggers wrote: > On Tue, Nov 22, 2022 at 03:06:32PM +0800, Tianjia Zhang wrote: >> SM4 is a symmetric algorithm widely used in China, this patch enables >> to use SM4-XTS mode to encrypt file content, and use SM4-CBC-CTS to >> encrypt filename. >> >> Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com> > > There is still no explanation here about why you believe this algorithm is > useful to support in fscrypt. > > - Eric Sorry, I will send a new version of patch to add these information. Best regards, Tianjia
diff --git a/Documentation/filesystems/fscrypt.rst b/Documentation/filesystems/fscrypt.rst index 5ba5817c17c2..af27e7b2c74f 100644 --- a/Documentation/filesystems/fscrypt.rst +++ b/Documentation/filesystems/fscrypt.rst @@ -336,6 +336,7 @@ Currently, the following pairs of encryption modes are supported: - AES-256-XTS for contents and AES-256-CTS-CBC for filenames - AES-128-CBC for contents and AES-128-CTS-CBC for filenames +- SM4-XTS for contents and SM4-CTS-CBC for filenames - Adiantum for both contents and filenames - AES-256-XTS for contents and AES-256-HCTR2 for filenames (v2 policies only) diff --git a/fs/crypto/keysetup.c b/fs/crypto/keysetup.c index f7407071a952..24e55c95abc3 100644 --- a/fs/crypto/keysetup.c +++ b/fs/crypto/keysetup.c @@ -44,6 +44,21 @@ struct fscrypt_mode fscrypt_modes[] = { .security_strength = 16, .ivsize = 16, }, + [FSCRYPT_MODE_SM4_XTS] = { + .friendly_name = "SM4-XTS", + .cipher_str = "xts(sm4)", + .keysize = 32, + .security_strength = 16, + .ivsize = 16, + .blk_crypto_mode = BLK_ENCRYPTION_MODE_SM4_XTS, + }, + [FSCRYPT_MODE_SM4_CTS] = { + .friendly_name = "SM4-CTS", + .cipher_str = "cts(cbc(sm4))", + .keysize = 16, + .security_strength = 16, + .ivsize = 16, + }, [FSCRYPT_MODE_ADIANTUM] = { .friendly_name = "Adiantum", .cipher_str = "adiantum(xchacha12,aes)", diff --git a/fs/crypto/policy.c b/fs/crypto/policy.c index 46757c3052ef..8e69bc0c35cd 100644 --- a/fs/crypto/policy.c +++ b/fs/crypto/policy.c @@ -71,6 +71,10 @@ static bool fscrypt_valid_enc_modes_v1(u32 contents_mode, u32 filenames_mode) filenames_mode == FSCRYPT_MODE_AES_128_CTS) return true; + if (contents_mode == FSCRYPT_MODE_SM4_XTS && + filenames_mode == FSCRYPT_MODE_SM4_CTS) + return true; + if (contents_mode == FSCRYPT_MODE_ADIANTUM && filenames_mode == FSCRYPT_MODE_ADIANTUM) return true; diff --git a/include/uapi/linux/fscrypt.h b/include/uapi/linux/fscrypt.h index a756b29afcc2..47dbd1994bfe 100644 --- a/include/uapi/linux/fscrypt.h +++ b/include/uapi/linux/fscrypt.h @@ -26,6 +26,8 @@ #define FSCRYPT_MODE_AES_256_CTS 4 #define FSCRYPT_MODE_AES_128_CBC 5 #define FSCRYPT_MODE_AES_128_CTS 6 +#define FSCRYPT_MODE_SM4_XTS 7 +#define FSCRYPT_MODE_SM4_CTS 8 #define FSCRYPT_MODE_ADIANTUM 9 #define FSCRYPT_MODE_AES_256_HCTR2 10 /* If adding a mode number > 10, update FSCRYPT_MODE_MAX in fscrypt_private.h */
SM4 is a symmetric algorithm widely used in China, this patch enables to use SM4-XTS mode to encrypt file content, and use SM4-CBC-CTS to encrypt filename. Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com> --- Documentation/filesystems/fscrypt.rst | 1 + fs/crypto/keysetup.c | 15 +++++++++++++++ fs/crypto/policy.c | 4 ++++ include/uapi/linux/fscrypt.h | 2 ++ 4 files changed, 22 insertions(+)