[PATCH v3 4/8] ima: define a new template field 'd-type' and a new template 'ima-ngv2'

[Mimi Zohar <zohar@xxxxxxxxxxxxx>]

In preparation to differentiate between regular file hashes and
fs-verity's file digests, define a new template field named 'd-type'.
Define and include the new 'd-type' field in the new template named
'ima-ngv2'.

Signed-off-by: Mimi Zohar <zohar@xxxxxxxxxxxxx>
---
 security/integrity/ima/ima_template.c     |  3 +++
 security/integrity/ima/ima_template_lib.c | 13 +++++++++++++
 security/integrity/ima/ima_template_lib.h |  2 ++
 3 files changed, 18 insertions(+)

diff --git a/security/integrity/ima/ima_template.c b/security/integrity/ima/ima_template.c
index 694560396be0..9d8253c6c52c 100644
--- a/security/integrity/ima/ima_template.c
+++ b/security/integrity/ima/ima_template.c
@@ -19,6 +19,7 @@ enum header_fields { HDR_PCR, HDR_DIGEST, HDR_TEMPLATE_NAME,
 static struct ima_template_desc builtin_templates[] = {
 	{.name = IMA_TEMPLATE_IMA_NAME, .fmt = IMA_TEMPLATE_IMA_FMT},
 	{.name = "ima-ng", .fmt = "d-ng|n-ng"},
+	{.name = "ima-ngv2", .fmt = "d-ng|n-ng|d-type"},
 	{.name = "ima-sig", .fmt = "d-ng|n-ng|sig"},
 	{.name = "ima-buf", .fmt = "d-ng|n-ng|buf"},
 	{.name = "ima-modsig", .fmt = "d-ng|n-ng|sig|d-modsig|modsig"},
@@ -39,6 +40,8 @@ static const struct ima_template_field supported_fields[] = {
 	 .field_show = ima_show_template_digest_ng},
 	{.field_id = "n-ng", .field_init = ima_eventname_ng_init,
 	 .field_show = ima_show_template_string},
+	{.field_id = "d-type", .field_init = ima_eventdigest_type_init,
+	 .field_show = ima_show_template_string},
 	{.field_id = "sig", .field_init = ima_eventsig_init,
 	 .field_show = ima_show_template_sig},
 	{.field_id = "buf", .field_init = ima_eventbuf_init,
diff --git a/security/integrity/ima/ima_template_lib.c b/security/integrity/ima/ima_template_lib.c
index d3aa511027cd..aa5d4a490657 100644
--- a/security/integrity/ima/ima_template_lib.c
+++ b/security/integrity/ima/ima_template_lib.c
@@ -387,6 +387,19 @@ int ima_eventdigest_ng_init(struct ima_event_data *event_data,
 					   hash_algo, field_data);
 }
 
+/*
+ * This function writes the digest type of an event.
+ */
+int ima_eventdigest_type_init(struct ima_event_data *event_data,
+			      struct ima_field_data *field_data)
+{
+	static const char * const digest_type[] = {"hash"};
+
+	return ima_write_template_field_data(digest_type[0],
+					     strlen(digest_type[0]),
+					     DATA_FMT_STRING, field_data);
+}
+
 /*
  * This function writes the digest of the file which is expected to match the
  * digest contained in the file's appended signature.
diff --git a/security/integrity/ima/ima_template_lib.h b/security/integrity/ima/ima_template_lib.h
index c71f1de95753..539a5e354925 100644
--- a/security/integrity/ima/ima_template_lib.h
+++ b/security/integrity/ima/ima_template_lib.h
@@ -38,6 +38,8 @@ int ima_eventname_init(struct ima_event_data *event_data,
 		       struct ima_field_data *field_data);
 int ima_eventdigest_ng_init(struct ima_event_data *event_data,
 			    struct ima_field_data *field_data);
+int ima_eventdigest_type_init(struct ima_event_data *event_data,
+			      struct ima_field_data *field_data);
 int ima_eventdigest_modsig_init(struct ima_event_data *event_data,
 				struct ima_field_data *field_data);
 int ima_eventname_ng_init(struct ima_event_data *event_data,
-- 
2.27.0