From: Eric Biggers <ebiggers@google.com>
Date: Sat, 30 Apr 2022 22:08:53 -0700
Subject: fscrypt: factor out fscrypt_policy_to_key_spec()
Git-commit: bfb9700bdf35417454a9bb8b67221d89d7c6e75a
Patch-mainline: v5.19-rc1
References: jsc#SES-1880
Factor out a function that builds the fscrypt_key_specifier for an
fscrypt_policy. Before this was only needed when finding the key for a
file, but now it will also be needed for test_dummy_encryption support.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20220501050857.538984-4-ebiggers@kernel.org
Acked-by: Luis Henriques <lhenriques@suse.de>
---
fs/crypto/fscrypt_private.h | 2 ++
fs/crypto/keysetup.c | 20 +++-----------------
fs/crypto/policy.c | 20 ++++++++++++++++++++
3 files changed, 25 insertions(+), 17 deletions(-)
diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h
index 33f08f1b1974..7c93325161b0 100644
--- a/fs/crypto/fscrypt_private.h
+++ b/fs/crypto/fscrypt_private.h
@@ -623,6 +623,8 @@ int fscrypt_setup_v1_file_key_via_subscribed_keyrings(struct fscrypt_info *ci);
bool fscrypt_policies_equal(const union fscrypt_policy *policy1,
const union fscrypt_policy *policy2);
+int fscrypt_policy_to_key_spec(const union fscrypt_policy *policy,
+ struct fscrypt_key_specifier *key_spec);
bool fscrypt_supported_policy(const union fscrypt_policy *policy_u,
const struct inode *inode);
int fscrypt_policy_from_context(union fscrypt_policy *policy_u,
diff --git a/fs/crypto/keysetup.c b/fs/crypto/keysetup.c
index 6b509af13e0d..c35711896bd4 100644
--- a/fs/crypto/keysetup.c
+++ b/fs/crypto/keysetup.c
@@ -425,23 +425,9 @@ static int setup_file_encryption_key(struct fscrypt_info *ci,
if (err)
return err;
- switch (ci->ci_policy.version) {
- case FSCRYPT_POLICY_V1:
- mk_spec.type = FSCRYPT_KEY_SPEC_TYPE_DESCRIPTOR;
- memcpy(mk_spec.u.descriptor,
- ci->ci_policy.v1.master_key_descriptor,
- FSCRYPT_KEY_DESCRIPTOR_SIZE);
- break;
- case FSCRYPT_POLICY_V2:
- mk_spec.type = FSCRYPT_KEY_SPEC_TYPE_IDENTIFIER;
- memcpy(mk_spec.u.identifier,
- ci->ci_policy.v2.master_key_identifier,
- FSCRYPT_KEY_IDENTIFIER_SIZE);
- break;
- default:
- WARN_ON(1);
- return -EINVAL;
- }
+ err = fscrypt_policy_to_key_spec(&ci->ci_policy, &mk_spec);
+ if (err)
+ return err;
key = fscrypt_find_master_key(ci->ci_inode->i_sb, &mk_spec);
if (IS_ERR(key)) {
diff --git a/fs/crypto/policy.c b/fs/crypto/policy.c
index ed3d623724cd..2a11276913a9 100644
--- a/fs/crypto/policy.c
+++ b/fs/crypto/policy.c
@@ -32,6 +32,26 @@ bool fscrypt_policies_equal(const union fscrypt_policy *policy1,
return !memcmp(policy1, policy2, fscrypt_policy_size(policy1));
}
+int fscrypt_policy_to_key_spec(const union fscrypt_policy *policy,
+ struct fscrypt_key_specifier *key_spec)
+{
+ switch (policy->version) {
+ case FSCRYPT_POLICY_V1:
+ key_spec->type = FSCRYPT_KEY_SPEC_TYPE_DESCRIPTOR;
+ memcpy(key_spec->u.descriptor, policy->v1.master_key_descriptor,
+ FSCRYPT_KEY_DESCRIPTOR_SIZE);
+ return 0;
+ case FSCRYPT_POLICY_V2:
+ key_spec->type = FSCRYPT_KEY_SPEC_TYPE_IDENTIFIER;
+ memcpy(key_spec->u.identifier, policy->v2.master_key_identifier,
+ FSCRYPT_KEY_IDENTIFIER_SIZE);
+ return 0;
+ default:
+ WARN_ON(1);
+ return -EINVAL;
+ }
+}
+
static const union fscrypt_policy *
fscrypt_get_dummy_policy(struct super_block *sb)
{