@@ -52,6 +52,10 @@ Description:
template:= name of a defined IMA template type
(eg, ima-ng). Only valid when action is "measure".
pcr:= decimal value
+ data_sources:= list of kernel subsystems that contain
+ kernel in-memory data critical to the integrity of the kernel.
+ Only valid when action is "measure" and func is
+ CRITICAL_DATA.
default policy:
# PROC_SUPER_MAGIC
@@ -934,7 +934,7 @@ enum {
Opt_uid_lt, Opt_euid_lt, Opt_fowner_lt,
Opt_appraise_type, Opt_appraise_flag,
Opt_permit_directio, Opt_pcr, Opt_template, Opt_keyrings,
- Opt_err
+ Opt_data_sources, Opt_err
};
static const match_table_t policy_tokens = {
@@ -971,6 +971,7 @@ static const match_table_t policy_tokens = {
{Opt_pcr, "pcr=%s"},
{Opt_template, "template=%s"},
{Opt_keyrings, "keyrings=%s"},
+ {Opt_data_sources, "data_sources=%s"},
{Opt_err, NULL}
};
@@ -1350,6 +1351,24 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
entry->flags |= IMA_KEYRINGS;
break;
+ case Opt_data_sources:
+ ima_log_string(ab, "data_sources",
+ args[0].from);
+
+ if (entry->data_sources) {
+ result = -EINVAL;
+ break;
+ }
+
+ entry->data_sources = ima_alloc_rule_opt_list(args);
+ if (IS_ERR(entry->data_sources)) {
+ result = PTR_ERR(entry->data_sources);
+ entry->data_sources = NULL;
+ break;
+ }
+
+ entry->flags |= IMA_DATA_SOURCES;
+ break;
case Opt_fsuuid:
ima_log_string(ab, "fsuuid", args[0].from);
@@ -1730,6 +1749,12 @@ int ima_policy_show(struct seq_file *m, void *v)
seq_puts(m, " ");
}
+ if (entry->flags & IMA_DATA_SOURCES) {
+ seq_puts(m, "data_sources=");
+ ima_show_rule_opt_list(m, entry->data_sources);
+ seq_puts(m, " ");
+ }
+
if (entry->flags & IMA_PCR) {
snprintf(tbuf, sizeof(tbuf), "%d", entry->pcr);
seq_printf(m, pt(Opt_pcr), tbuf);
System administrators should be able to limit which kernel subsystems they want to measure the critical data for. To enable that, an IMA policy condition to choose specific kernel subsystems is needed. This policy condition would constrain the measurement of the critical data to the given kernel subsystems. Add a new IMA policy condition - "data_sources:=" to the IMA func CRITICAL_DATA to allow measurement of various kernel subsystems. This policy condition would enable the system administrators to restrict the measurement to the subsystems listed in "data_sources:=". Limit the measurement to the subsystems that are specified in the IMA policy - CRITICAL_DATA+"data_sources:=". If "data_sources:=" is not provided with the func CRITICAL_DATA, the data from all the supported kernel subsystems is measured. Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com> --- Documentation/ABI/testing/ima_policy | 4 ++++ security/integrity/ima/ima_policy.c | 27 ++++++++++++++++++++++++++- 2 files changed, 30 insertions(+), 1 deletion(-)