@@ -1591,6 +1591,9 @@ struct lsm_info {
int *enabled; /* Optional: controlled by CONFIG_LSM */
int (*init)(void); /* Required. */
struct lsm_blob_sizes *blobs; /* Optional: for blob sharing. */
+ int (*security_state)(void); /* Optional: for measuring the state
+ * of the security module.
+ */
};
extern struct lsm_info __start_lsm_info[], __end_lsm_info[];
@@ -86,6 +86,9 @@ static __initconst const char * const builtin_lsm_order = CONFIG_LSM;
static __initdata struct lsm_info **ordered_lsms;
static __initdata struct lsm_info *exclusive;
+static struct lsm_info *security_state_lsms;
+static int security_state_lsms_count;
+
static __initdata bool debug;
#define init_debug(...) \
do { \
@@ -235,6 +238,45 @@ static void __init initialize_lsm(struct lsm_info *lsm)
}
}
+static int measure_security_state(struct lsm_info *lsm)
+{
+ if (!lsm->security_state)
+ return 0;
+
+ return lsm->security_state();
+}
+
+static void __init initialize_security_state_lsms(void)
+{
+ struct lsm_info **lsm;
+ int count = 0;
+ int inx;
+
+ for (lsm = ordered_lsms; *lsm; lsm++) {
+ if ((*lsm)->security_state)
+ count++;
+ }
+
+ if (count == 0)
+ return;
+
+ security_state_lsms = kcalloc(count, sizeof(struct lsm_info),
+ GFP_KERNEL);
+ if (!security_state_lsms)
+ return;
+
+ inx = 0;
+ for (lsm = ordered_lsms; *lsm; lsm++) {
+ if ((*lsm)->security_state) {
+ security_state_lsms[inx].security_state =
+ (*lsm)->security_state;
+ inx++;
+ }
+ }
+
+ security_state_lsms_count = count;
+}
+
/* Populate ordered LSMs list from comma-separated LSM name list. */
static void __init ordered_lsm_parse(const char *order, const char *origin)
{
@@ -352,8 +394,12 @@ static void __init ordered_lsm_init(void)
lsm_early_cred((struct cred *) current->cred);
lsm_early_task(current);
- for (lsm = ordered_lsms; *lsm; lsm++)
+ for (lsm = ordered_lsms; *lsm; lsm++) {
initialize_lsm(*lsm);
+ measure_security_state(*lsm);
+ }
+
+ initialize_security_state_lsms();
kfree(ordered_lsms);
}
The security modules that require their data to be measured using the IMA subsystem need to define a function that the LSM can call to trigger the measurement. Add a function pointer field namely security_state in lsm_info structure. Update LSM to call this security module function, if defined, to measure the security module's data using the IMA subsystem. Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> --- include/linux/lsm_hooks.h | 3 +++ security/security.c | 48 ++++++++++++++++++++++++++++++++++++++- 2 files changed, 50 insertions(+), 1 deletion(-)