[PATCH v4 04/10] IMA: Read keyrings= option from the IMA policy into ima_rule_entry

[Lakshmi Ramasubramanian <nramas@linux.microsoft.com>]

"keyrings=" option, if specified in the IMA policy, needs to be
stored in the list of IMA rules when the configured IMA policy is read.

This patch defines a new policy token enum namely Opt_keyrings
for reading "keyrings=" option from the IMA policy.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
 security/integrity/ima/ima_policy.c | 28 +++++++++++++++++++++++++++-
 1 file changed, 27 insertions(+), 1 deletion(-)

diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index 4d68ad8ed91c..74a727dc6030 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -768,7 +768,8 @@ enum {
 	Opt_uid_gt, Opt_euid_gt, Opt_fowner_gt,
 	Opt_uid_lt, Opt_euid_lt, Opt_fowner_lt,
 	Opt_appraise_type, Opt_appraise_flag,
-	Opt_permit_directio, Opt_pcr, Opt_template, Opt_err
+	Opt_permit_directio, Opt_pcr, Opt_template, Opt_keyrings,
+	Opt_err
 };
 
 static const match_table_t policy_tokens = {
@@ -804,6 +805,7 @@ static const match_table_t policy_tokens = {
 	{Opt_permit_directio, "permit_directio"},
 	{Opt_pcr, "pcr=%s"},
 	{Opt_template, "template=%s"},
+	{Opt_keyrings, "keyrings=%s"},
 	{Opt_err, NULL}
 };
 
@@ -1051,6 +1053,23 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
 			result = 0;
 			entry->flags |= IMA_FSNAME;
 			break;
+		case Opt_keyrings:
+			ima_log_string(ab, "keyrings", args[0].from);
+
+			if ((entry->keyrings) ||
+			    (entry->action != MEASURE) ||
+			    (entry->func != KEYRING_CHECK)) {
+				result = -EINVAL;
+				break;
+			}
+			entry->keyrings = kstrdup(args[0].from, GFP_KERNEL);
+			if (!entry->keyrings) {
+				result = -ENOMEM;
+				break;
+			}
+			result = 0;
+			entry->flags |= IMA_KEYRINGS;
+			break;
 		case Opt_fsuuid:
 			ima_log_string(ab, "fsuuid", args[0].from);
 
@@ -1426,6 +1445,13 @@ int ima_policy_show(struct seq_file *m, void *v)
 		seq_puts(m, " ");
 	}
 
+	if (entry->flags & IMA_KEYRINGS) {
+		if (entry->keyrings != NULL)
+			snprintf(tbuf, sizeof(tbuf), "%s", entry->keyrings);
+		seq_printf(m, pt(Opt_keyrings), tbuf);
+		seq_puts(m, " ");
+	}
+
 	if (entry->flags & IMA_PCR) {
 		snprintf(tbuf, sizeof(tbuf), "%d", entry->pcr);
 		seq_printf(m, pt(Opt_pcr), tbuf);
-- 
2.17.1