lkml.org 
[lkml]   [2013]   [Nov]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 5/6] ima: do not include field length in template digest calc for ima template
Date
To maintain compatibility with userspace tools, the field length must not
be included in the template digest calculation for the 'ima' template.

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
---
security/integrity/ima/ima.h | 3 ++-
security/integrity/ima/ima_api.c | 1 +
security/integrity/ima/ima_crypto.c | 20 ++++++++++++--------
3 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index bf03c6a..a21cf70 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -97,7 +97,8 @@ int ima_add_template_entry(struct ima_template_entry *entry, int violation,
const char *op, struct inode *inode,
const unsigned char *filename);
int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash);
-int ima_calc_field_array_hash(struct ima_field_data *field_data, int num_fields,
+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);
int __init ima_calc_boot_aggregate(struct ima_digest_data *hash);
void ima_add_violation(struct file *file, const unsigned char *filename,
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index 0e75408..8037484 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -94,6 +94,7 @@ int ima_store_template(struct ima_template_entry *entry,
/* 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);
if (result < 0) {
integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode,
diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
index e22708b..fdf60de 100644
--- a/security/integrity/ima/ima_crypto.c
+++ b/security/integrity/ima/ima_crypto.c
@@ -140,6 +140,7 @@ 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 crypto_shash *tfm)
@@ -160,12 +161,13 @@ static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
return rc;

for (i = 0; i < num_fields; i++) {
- rc = crypto_shash_update(&desc.shash,
- (const u8 *) &field_data[i].len,
- sizeof(field_data[i].len));
- if (rc)
- break;
-
+ if (strcmp(td->name, IMA_TEMPLATE_IMA_NAME) != 0) {
+ rc = crypto_shash_update(&desc.shash,
+ (const u8 *) &field_data[i].len,
+ sizeof(field_data[i].len));
+ if (rc)
+ break;
+ }
rc = crypto_shash_update(&desc.shash, field_data[i].data,
field_data[i].len);
if (rc)
@@ -178,7 +180,8 @@ static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
return rc;
}

-int ima_calc_field_array_hash(struct ima_field_data *field_data, int num_fields,
+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 crypto_shash *tfm;
@@ -188,7 +191,8 @@ int ima_calc_field_array_hash(struct ima_field_data *field_data, int num_fields,
if (IS_ERR(tfm))
return PTR_ERR(tfm);

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

ima_free_tfm(tfm);

--
1.8.1.4
[unhandled content-type:application/x-pkcs7-signature]
\
 
 \ /
  Last update: 2013-11-15 15:01    [W:0.092 / U:0.056 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site