[PATCH 2/4] ima: define a new signature type named IMA_VERITY_DIGSIG

Mimi Zohar
2021-11-29T17:03:40Z

To differentiate between a regular file hash and an fs-verity file digest
based signature stored as security.ima xattr, define a new signature type
named IMA_VERITY_DIGSIG.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
---
security/integrity/ima/ima_appraise.c | 6 ++++++
security/integrity/integrity.h | 1 +
2 files changed, 7 insertions(+)

diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
index dbba51583e7c..d43a27a9a9b6 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -13,7 +13,9 @@
#include <linux/magic.h>
#include <linux/ima.h>
#include <linux/evm.h>
+#include <linux/fsverity.h>
#include <keys/system_keyring.h>
+#include <uapi/linux/fsverity.h>

#include "ima.h"

@@ -183,6 +185,8 @@ enum hash_algo ima_get_hash_algo(const struct evm_ima_xattr_data *xattr_value,
return ima_hash_algo;

switch (xattr_value->type) {
+ case IMA_VERITY_DIGSIG:
+ fallthrough;
case EVM_IMA_XATTR_DIGSIG:
sig = (typeof(sig))xattr_value;
if (sig->version != 2 || xattr_len <= sizeof(*sig)
@@ -272,6 +276,8 @@ static int xattr_verify(enum ima_hooks func, struct integrity_iint_cache *iint,
}
*status = INTEGRITY_PASS;
break;
+ case IMA_VERITY_DIGSIG:
+ fallthrough;
case EVM_IMA_XATTR_DIGSIG:
set_bit(IMA_DIGSIG, &iint->atomic_flags);
rc = integrity_digsig_verify(INTEGRITY_KEYRING_IMA,
diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h
index 547425c20e11..94f9ba55e840 100644
--- a/security/integrity/integrity.h
+++ b/security/integrity/integrity.h
@@ -77,6 +77,7 @@ enum evm_ima_xattr_type {
EVM_IMA_XATTR_DIGSIG,
IMA_XATTR_DIGEST_NG,
EVM_XATTR_PORTABLE_DIGSIG,
+ IMA_VERITY_DIGSIG,
IMA_XATTR_LAST
};

--
2.27.0