Commit 9e90f30e authored by Eric Biggers's avatar Eric Biggers
Browse files

fs-verity: rename fsverity_signed_digest to fsverity_formatted_digest 



The name "struct fsverity_signed_digest" is causing confusion because it
isn't actually a signed digest, but rather it's the way that the digest
is formatted in order to be signed.  Rename it to
"struct fsverity_formatted_digest" to prevent this confusion.

Also update the struct's comment to clarify that it's specific to the
built-in signature verification support and isn't a requirement for all
fs-verity users.

I'll be renaming this struct in fsverity-utils too.

Acked-by: default avatarLuca Boccassi <luca.boccassi@microsoft.com>
Link: https://lore.kernel.org/r/20201113211918.71883-3-ebiggers@kernel.org


Signed-off-by: default avatarEric Biggers <ebiggers@google.com>
parent 7bf765dd

Documentation/filesystems/fsverity.rst

+1 −1
Original line number Diff line number Diff line
@@ -372,7 +372,7 @@ kernel. Specifically, it adds support for: 
File measurements must be signed in the following format, which is

similar to the structure used by `FS_IOC_MEASURE_VERITY`_::



    struct fsverity_signed_digest {

    struct fsverity_formatted_digest {

            char magic[8];                  /* must be "FSVerity" */

            __le16 digest_algorithm;

            __le16 digest_size;

fs/verity/fsverity_private.h

+12 −5
Original line number Diff line number Diff line
@@ -101,12 +101,19 @@ struct fsverity_descriptor { 
					 sizeof(struct fsverity_descriptor))



/*

 * Format in which verity file measurements are signed.  This is the same as

 * 'struct fsverity_digest', except here some magic bytes are prepended to

 * provide some context about what is being signed in case the same key is used

 * for non-fsverity purposes, and here the fields have fixed endianness.

 * Format in which verity file measurements are signed in built-in signatures.

 * This is the same as 'struct fsverity_digest', except here some magic bytes

 * are prepended to provide some context about what is being signed in case the

 * same key is used for non-fsverity purposes, and here the fields have fixed

 * endianness.

 *

 * This struct is specific to the built-in signature verification support, which

 * is optional.  fs-verity users may also verify signatures in userspace, in

 * which case userspace is responsible for deciding on what bytes are signed.

 * This struct may still be used, but it doesn't have to be.  For example,

 * userspace could instead use a string like "sha256:$digest_as_hex_string".

 */

struct fsverity_signed_digest {

struct fsverity_formatted_digest {

	char magic[8];			/* must be "FSVerity" */

	__le16 digest_algorithm;

	__le16 digest_size;

fs/verity/signature.c

+1 −1
Original line number Diff line number Diff line
@@ -44,7 +44,7 @@ int fsverity_verify_signature(const struct fsverity_info *vi, 
	const struct inode *inode = vi->inode;

	const struct fsverity_hash_alg *hash_alg = vi->tree_params.hash_alg;

	const u32 sig_size = le32_to_cpu(desc->sig_size);

	struct fsverity_signed_digest *d;

	struct fsverity_formatted_digest *d;

	int err;



	if (sig_size == 0) {