ima: extend the measurement list to include the file signature
This patch defines a new template called 'ima-sig', which includes
the file signature in the template data, in addition to the file's
digest and pathname.
A template is composed of a set of fields. Associated with each
field is an initialization and display function. This patch defines
a new template field called 'sig', the initialization function
ima_eventsig_init(), and the display function ima_show_template_sig().
This patch modifies the .field_init() function definition to include
the 'security.ima' extended attribute and length.
Changelog:
- remove unused code (Dmitry Kasatkin)
- avoid calling ima_write_template_field_data() unnecesarily (Roberto Sassu)
- rename DATA_FMT_SIG to DATA_FMT_HEX
- cleanup ima_eventsig_init() based on Roberto's comments
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
diff --git a/security/integrity/ima/ima_template_lib.c b/security/integrity/ima/ima_template_lib.c
index 7d84144..6d66ad6 100644
--- a/security/integrity/ima/ima_template_lib.c
+++ b/security/integrity/ima/ima_template_lib.c
@@ -28,7 +28,8 @@
DATA_FMT_DIGEST = 0,
DATA_FMT_DIGEST_WITH_ALGO,
DATA_FMT_EVENT_NAME,
- DATA_FMT_STRING
+ DATA_FMT_STRING,
+ DATA_FMT_HEX
};
static int ima_write_template_field_data(const void *data, const u32 datalen,
@@ -90,6 +91,9 @@
buf_ptr += 2;
buflen -= buf_ptr - field_data->data;
case DATA_FMT_DIGEST:
+ case DATA_FMT_HEX:
+ if (!buflen)
+ break;
ima_print_digest(m, buf_ptr, buflen);
break;
case DATA_FMT_STRING:
@@ -147,6 +151,12 @@
ima_show_template_field_data(m, show, DATA_FMT_STRING, field_data);
}
+void ima_show_template_sig(struct seq_file *m, enum ima_show_type show,
+ struct ima_field_data *field_data)
+{
+ ima_show_template_field_data(m, show, DATA_FMT_HEX, field_data);
+}
+
static int ima_eventdigest_init_common(u8 *digest, u32 digestsize, u8 hash_algo,
struct ima_field_data *field_data,
bool size_limit)
@@ -190,6 +200,7 @@
*/
int ima_eventdigest_init(struct integrity_iint_cache *iint, struct file *file,
const unsigned char *filename,
+ struct evm_ima_xattr_data *xattr_value, int xattr_len,
struct ima_field_data *field_data)
{
struct {
@@ -237,7 +248,8 @@
*/
int ima_eventdigest_ng_init(struct integrity_iint_cache *iint,
struct file *file, const unsigned char *filename,
- struct ima_field_data *field_data)
+ struct evm_ima_xattr_data *xattr_value,
+ int xattr_len, struct ima_field_data *field_data)
{
u8 *cur_digest = NULL, hash_algo = HASH_ALGO__LAST;
u32 cur_digestsize = 0;
@@ -295,6 +307,7 @@
*/
int ima_eventname_init(struct integrity_iint_cache *iint, struct file *file,
const unsigned char *filename,
+ struct evm_ima_xattr_data *xattr_value, int xattr_len,
struct ima_field_data *field_data)
{
return ima_eventname_init_common(iint, file, filename,
@@ -306,8 +319,29 @@
*/
int ima_eventname_ng_init(struct integrity_iint_cache *iint, struct file *file,
const unsigned char *filename,
+ struct evm_ima_xattr_data *xattr_value, int xattr_len,
struct ima_field_data *field_data)
{
return ima_eventname_init_common(iint, file, filename,
field_data, false);
}
+
+/*
+ * ima_eventsig_init - include the file signature as part of the template data
+ */
+int ima_eventsig_init(struct integrity_iint_cache *iint, struct file *file,
+ const unsigned char *filename,
+ struct evm_ima_xattr_data *xattr_value, int xattr_len,
+ struct ima_field_data *field_data)
+{
+ enum data_formats fmt = DATA_FMT_HEX;
+ int rc = 0;
+
+ if ((!xattr_value) || (xattr_value->type != EVM_IMA_XATTR_DIGSIG))
+ goto out;
+
+ rc = ima_write_template_field_data(xattr_value, xattr_len, fmt,
+ field_data);
+out:
+ return rc;
+}