[PATCH 3/8] ima: store template digest directly in ima_template_entry

Roberto Sassu
2020-01-27T17:06:36Z

In preparation for the patch that calculates a digest for each allocated
PCR bank, this patch passes to ima_calc_field_array_hash() the
ima_template_entry structure, so that digests can be directly stored in
that structure instead of ima_digest_data.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
---
security/integrity/ima/ima.h | 3 +--
security/integrity/ima/ima_api.c | 12 +-----------
security/integrity/ima/ima_crypto.c | 18 +++++++-----------
3 files changed, 9 insertions(+), 24 deletions(-)

diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 6bb3152b3e24..6238c50ae44e 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -138,8 +138,7 @@ int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash);
int ima_calc_buffer_hash(const void *buf, loff_t len,
struct ima_digest_data *hash);
int ima_calc_field_array_hash(struct ima_field_data *field_data,
- struct ima_template_desc *desc, int num_fields,
- struct ima_digest_data *hash);
+ struct ima_template_entry *entry);
int __init ima_calc_boot_aggregate(struct ima_digest_data *hash);
void ima_add_violation(struct file *file, const unsigned char *filename,
struct integrity_iint_cache *iint,
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index f6bc00914aa5..2ef5a40c7ca5 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -96,26 +96,16 @@ int ima_store_template(struct ima_template_entry *entry,
static const char audit_cause[] = "hashing_error";
char *template_name = entry->template_desc->name;
int result;
- struct {
- struct ima_digest_data hdr;
- char digest[TPM_DIGEST_SIZE];
- } hash;

if (!violation) {
- int num_fields = entry->template_desc->num_fields;
-
- /* this function uses default algo */
- hash.hdr.algo = HASH_ALGO_SHA1;
result = ima_calc_field_array_hash(&entry->template_data[0],
- entry->template_desc,
- num_fields, &hash.hdr);
+ entry);
if (result < 0) {
integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode,
template_name, op,
audit_cause, result, 0);
return result;
}
- memcpy(entry->digest, hash.hdr.digest, hash.hdr.length);
}
entry->pcr = pcr;
result = ima_add_template_entry(entry, violation, op, inode, filename);
diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
index 7967a6904851..f2d9d4b18499 100644
--- a/security/integrity/ima/ima_crypto.c
+++ b/security/integrity/ima/ima_crypto.c
@@ -466,18 +466,16 @@ int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash)
* Calculate the hash of template data
*/
static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
- struct ima_template_desc *td,
- int num_fields,
- struct ima_digest_data *hash,
+ struct ima_template_entry *entry,
struct crypto_shash *tfm)
{
SHASH_DESC_ON_STACK(shash, tfm);
+ struct ima_template_desc *td = entry->template_desc;
+ int num_fields = entry->template_desc->num_fields;
int rc, i;

shash->tfm = tfm;

- hash->length = crypto_shash_digestsize(tfm);
-
rc = crypto_shash_init(shash);
if (rc != 0)
return rc;
@@ -506,24 +504,22 @@ static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
}

if (!rc)
- rc = crypto_shash_final(shash, hash->digest);
+ rc = crypto_shash_final(shash, entry->digest);

return rc;
}

int ima_calc_field_array_hash(struct ima_field_data *field_data,
- struct ima_template_desc *desc, int num_fields,
- struct ima_digest_data *hash)
+ struct ima_template_entry *entry)
{
struct crypto_shash *tfm;
int rc;

- tfm = ima_alloc_tfm(hash->algo);
+ tfm = ima_alloc_tfm(HASH_ALGO_SHA1);
if (IS_ERR(tfm))
return PTR_ERR(tfm);

- rc = ima_calc_field_array_hash_tfm(field_data, desc, num_fields,
- hash, tfm);
+ rc = ima_calc_field_array_hash_tfm(field_data, entry, tfm);

ima_free_tfm(tfm);

--
2.17.1