ima: provide hash algo info in the xattr

All files labeled with 'security.ima' hashes, are hashed using the
same hash algorithm.  Changing from one hash algorithm to another,
requires relabeling the filesystem.  This patch defines a new xattr
type, which includes the hash algorithm, permitting different files
to be hashed with different algorithms.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

1 files changed, 12 insertions, 1 deletions

diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h
index 5429ca59125b..2fb5e53e927f 100644
--- a/security/integrity/integrity.h
+++ b/security/integrity/integrity.h
@@ -54,6 +54,7 @@ enum evm_ima_xattr_type {
 	IMA_XATTR_DIGEST = 0x01,
 	EVM_XATTR_HMAC,
 	EVM_IMA_XATTR_DIGSIG,
+	IMA_XATTR_DIGEST_NG,
 };
 
 struct evm_ima_xattr_data {
@@ -66,7 +67,17 @@ struct evm_ima_xattr_data {
 struct ima_digest_data {
 	u8 algo;
 	u8 length;
-	u8 type;
+	union {
+		struct {
+			u8 unused;
+			u8 type;
+		} sha1;
+		struct {
+			u8 type;
+			u8 algo;
+		} ng;
+		u8 data[2];
+	} xattr;
 	u8 digest[0];
 } __packed;