[dm-devel] [PATCH 5/6] dm ima: update dm target attributes for ima measurements

[Tushar Sugandhi]

Certain DM targets ('integrity', 'multipath', 'verity') need to update the
way their attributes are recorded in the ima log, so that the attestation
servers can interpret the data correctly and decide if the devices
meet the attestation requirements.  For instance, the "mode=%c" attribute
in the 'integrity' target is measured twice, the 'verity' target is
missing the attribute "root_hash_sig_key_desc=%s", and the 'multipath'
target needs to index the attributes properly.

Update 'integrity' target to remove the duplicate measurement of
the attribute "mode=%c".  Add "root_hash_sig_key_desc=%s" attribute
for the 'verity' target.  Index various attributes in 'multipath'
target.  Also, add "nr_priority_groups=%u" attribute to 'multipath'
target to record the number of priority groups.

Signed-off-by: Tushar Sugandhi <tusharsu at linux.microsoft.com>
Suggested-by: Thore Sommer <public at thson.de>
---
 drivers/md/dm-integrity.c     |  1 -
 drivers/md/dm-mpath.c         | 26 ++++++++++++++++++--------
 drivers/md/dm-verity-target.c |  2 ++
 3 files changed, 20 insertions(+), 9 deletions(-)

diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c
index 40f8116c8e44..6e0b2f2f5911 100644
--- a/drivers/md/dm-integrity.c
+++ b/drivers/md/dm-integrity.c
@@ -3328,7 +3328,6 @@ static void dm_integrity_status(struct dm_target *ti, status_type_t type,
 		DMEMIT(",journal_sectors=%u", ic->initial_sectors - SB_SECTORS);
 		DMEMIT(",interleave_sectors=%u", 1U << ic->sb->log2_interleave_sectors);
 		DMEMIT(",buffer_sectors=%u", 1U << ic->log2_buffer_sectors);
-		DMEMIT(",mode=%c", ic->mode);
 		DMEMIT(";");
 		break;
 	}
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index c3c514a9edbb..694aaca4eea2 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -1790,7 +1790,7 @@ static void multipath_resume(struct dm_target *ti)
 static void multipath_status(struct dm_target *ti, status_type_t type,
 			     unsigned status_flags, char *result, unsigned maxlen)
 {
-	int sz = 0;
+	int sz = 0, pg_counter, pgpath_counter;
 	unsigned long flags;
 	struct multipath *m = ti->private;
 	struct priority_group *pg;
@@ -1906,7 +1906,12 @@ static void multipath_status(struct dm_target *ti, status_type_t type,
 		break;
 
 	case STATUSTYPE_IMA:
+		sz = 0; /*reset the result pointer*/
+
 		DMEMIT_TARGET_NAME_VERSION(ti->type);
+		DMEMIT(",nr_priority_groups=%u", m->nr_priority_groups);
+
+		pg_counter = 0;
 		list_for_each_entry(pg, &m->priority_groups, list) {
 			if (pg->bypassed)
 				state = 'D';	/* Disabled */
@@ -1914,21 +1919,26 @@ static void multipath_status(struct dm_target *ti, status_type_t type,
 				state = 'A';	/* Currently Active */
 			else
 				state = 'E';	/* Enabled */
-			DMEMIT(",pg_state=%c", state);
-			DMEMIT(",nr_pgpaths=%u", pg->nr_pgpaths);
-			DMEMIT(",path_selector_name=%s", pg->ps.type->name);
+			DMEMIT(",pg_state_%d=%c", pg_counter, state);
+			DMEMIT(",nr_pgpaths_%d=%u", pg_counter, pg->nr_pgpaths);
+			DMEMIT(",path_selector_name_%d=%s", pg_counter, pg->ps.type->name);
 
+			pgpath_counter = 0;
 			list_for_each_entry(p, &pg->pgpaths, list) {
-				DMEMIT(",path_name=%s,is_active=%c,fail_count=%u",
-				       p->path.dev->name, p->is_active ? 'A' : 'F',
-				       p->fail_count);
+				DMEMIT(",path_name_%d_%d=%s,is_active_%d_%d=%c,fail_count_%d_%d=%u",
+				       pg_counter, pgpath_counter, p->path.dev->name,
+				       pg_counter, pgpath_counter, p->is_active ? 'A' : 'F',
+				       pg_counter, pgpath_counter, p->fail_count);
 				if (pg->ps.type->status) {
-					DMEMIT(",path_selector_status=");
+					DMEMIT(",path_selector_status_%d_%d=",
+					       pg_counter, pgpath_counter);
 					sz += pg->ps.type->status(&pg->ps, &p->path,
 								  type, result + sz,
 								  maxlen - sz);
 				}
+				pgpath_counter++;
 			}
+			pg_counter++;
 		}
 		DMEMIT(";");
 		break;
diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c
index bfefa100c265..22a5ac82446a 100644
--- a/drivers/md/dm-verity-target.c
+++ b/drivers/md/dm-verity-target.c
@@ -794,6 +794,8 @@ static void verity_status(struct dm_target *ti, status_type_t type,
 
 		DMEMIT(",ignore_zero_blocks=%c", v->zero_digest ? 'y' : 'n');
 		DMEMIT(",check_at_most_once=%c", v->validated_blocks ? 'y' : 'n');
+		if (v->signature_key_desc)
+			DMEMIT(",root_hash_sig_key_desc=%s", v->signature_key_desc);
 
 		if (v->mode != DM_VERITY_MODE_EIO) {
 			DMEMIT(",verity_mode=");
-- 
2.32.0