From: Mimi Zohar <zohar@linux.ibm.com>
To: linux-integrity@vger.kernel.org
Cc: Mimi Zohar <zohar@linux.ibm.com>,
Eric Biggers <ebiggers@kernel.org>,
linux-fscrypt@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v1 5/5] fsverity: update the documentation
Date: Thu, 2 Dec 2021 16:55:07 -0500 [thread overview]
Message-ID: <20211202215507.298415-6-zohar@linux.ibm.com> (raw)
In-Reply-To: <20211202215507.298415-1-zohar@linux.ibm.com>
Update the fsverity documentation related to IMA signature support.
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
---
Documentation/filesystems/fsverity.rst | 22 +++++++++++++---------
1 file changed, 13 insertions(+), 9 deletions(-)
diff --git a/Documentation/filesystems/fsverity.rst b/Documentation/filesystems/fsverity.rst
index 1d831e3cbcb3..c71f6e365df5 100644
--- a/Documentation/filesystems/fsverity.rst
+++ b/Documentation/filesystems/fsverity.rst
@@ -74,8 +74,12 @@ authenticating the files is up to userspace. However, to meet some
users' needs, fs-verity optionally supports a simple signature
verification mechanism where users can configure the kernel to require
that all fs-verity files be signed by a key loaded into a keyring; see
-`Built-in signature verification`_. Support for fs-verity file hashes
-in IMA (Integrity Measurement Architecture) policies is also planned.
+`Built-in signature verification`_.
+
+IMA (Integrity Measurement Architecture) supports fs-verity file
+digests based signatures stored as security.ima xattrs, which are
+identified by the signature type IMA_VERITY_DIGSIG.
+
User API
========
@@ -653,13 +657,13 @@ weren't already directly answered in other parts of this document.
hashed and what to do with those hashes, such as log them,
authenticate them, or add them to a measurement list.
- IMA is planned to support the fs-verity hashing mechanism as an
- alternative to doing full file hashes, for people who want the
- performance and security benefits of the Merkle tree based hash.
- But it doesn't make sense to force all uses of fs-verity to be
- through IMA. As a standalone filesystem feature, fs-verity
- already meets many users' needs, and it's testable like other
- filesystem features e.g. with xfstests.
+ IMA supports the fs-verity hashing mechanism as an alternative
+ to doing full file hashes, for people who want the performance
+ and security benefits of the Merkle tree based hash. But it
+ doesn't make sense to force all uses of fs-verity to be through
+ IMA. As a standalone filesystem feature, fs-verity already meets
+ many users' needs, and it's testable like other filesystem
+ features e.g. with xfstests.
:Q: Isn't fs-verity useless because the attacker can just modify the
hashes in the Merkle tree, which is stored on-disk?
--
2.27.0
next prev parent reply other threads:[~2021-12-02 21:55 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-12-02 21:55 [PATCH v1 0/5] ima: support fs-verity signatures stored as Mimi Zohar
2021-12-02 21:55 ` [PATCH v1 1/5] fs-verity: define a function to return the integrity protected file digest Mimi Zohar
2021-12-02 22:15 ` Eric Biggers
2021-12-02 21:55 ` [PATCH v1 2/5] ima: define a new signature type named IMA_VERITY_DIGSIG Mimi Zohar
2021-12-02 21:55 ` [PATCH v1 3/5] ima: limit including fs-verity's file digest in measurement list Mimi Zohar
2021-12-02 22:22 ` Eric Biggers
2021-12-02 22:55 ` Mimi Zohar
2021-12-02 21:55 ` [PATCH v1 4/5] ima: support fs-verity file digest based signatures Mimi Zohar
2021-12-02 22:07 ` Eric Biggers
2021-12-02 22:13 ` Mimi Zohar
2021-12-02 22:18 ` Eric Biggers
2021-12-31 15:35 ` Mimi Zohar
2022-01-05 23:37 ` Eric Biggers
2022-01-09 20:45 ` Vitaly Chikunov
2022-01-09 21:07 ` Eric Biggers
2022-01-15 5:31 ` Vitaly Chikunov
2022-01-15 6:21 ` Eric Biggers
2022-01-16 3:31 ` Stefan Berger
2022-01-16 5:24 ` Stefan Berger
2022-01-19 0:49 ` Eric Biggers
2022-01-19 15:41 ` Stefan Berger
2022-01-16 17:01 ` Mimi Zohar
2022-01-19 0:39 ` Eric Biggers
2022-01-20 16:39 ` Mimi Zohar
2022-01-20 21:05 ` Eric Biggers
2021-12-02 21:55 ` Mimi Zohar [this message]
2021-12-02 22:09 ` [PATCH v1 5/5] fsverity: update the documentation Eric Biggers
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