SELinux: Add a capabilities bitmap to SELinux policy version 22
Add a new policy capabilities bitmap to SELinux policy version 22. This bitmap
will enable the security server to query the policy to determine which features
it supports.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index 8dfaa3e..8ee04a4 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -16,12 +16,13 @@
* Updated: Hewlett-Packard <paul.moore@hp.com>
*
* Added support for NetLabel
+ * Added support for the policy capability bitmap
*
* Updated: Chad Sellers <csellers@tresys.com>
*
* Added validation of kernel classes and permissions
*
- * Copyright (C) 2006 Hewlett-Packard Development Company, L.P.
+ * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
* Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
* Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
* Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
@@ -59,6 +60,8 @@
extern void selnl_notify_policyload(u32 seqno);
unsigned int policydb_loaded_version;
+int selinux_policycap_netpeer;
+
/*
* This is declared in avc.c
*/
@@ -1299,6 +1302,12 @@
goto out;
}
+static void security_load_policycaps(void)
+{
+ selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps,
+ POLICYDB_CAPABILITY_NETPEER);
+}
+
extern void selinux_complete_init(void);
static int security_preserve_bools(struct policydb *p);
@@ -1346,6 +1355,7 @@
avtab_cache_destroy();
return -EINVAL;
}
+ security_load_policycaps();
policydb_loaded_version = policydb.policyvers;
ss_initialized = 1;
seqno = ++latest_granting;
@@ -1404,6 +1414,7 @@
POLICY_WRLOCK;
memcpy(&policydb, &newpolicydb, sizeof policydb);
sidtab_set(&sidtab, &newsidtab);
+ security_load_policycaps();
seqno = ++latest_granting;
policydb_loaded_version = policydb.policyvers;
POLICY_WRUNLOCK;
@@ -2148,6 +2159,60 @@
return policydb.allow_unknown;
}
+/**
+ * security_get_policycaps - Query the loaded policy for its capabilities
+ * @len: the number of capability bits
+ * @values: the capability bit array
+ *
+ * Description:
+ * Get an array of the policy capabilities in @values where each entry in
+ * @values is either true (1) or false (0) depending the policy's support of
+ * that feature. The policy capabilities are defined by the
+ * POLICYDB_CAPABILITY_* enums. The size of the array is stored in @len and it
+ * is up to the caller to free the array in @values. Returns zero on success,
+ * negative values on failure.
+ *
+ */
+int security_get_policycaps(int *len, int **values)
+{
+ int rc = -ENOMEM;
+ unsigned int iter;
+
+ POLICY_RDLOCK;
+
+ *values = kcalloc(POLICYDB_CAPABILITY_MAX, sizeof(int), GFP_ATOMIC);
+ if (*values == NULL)
+ goto out;
+ for (iter = 0; iter < POLICYDB_CAPABILITY_MAX; iter++)
+ (*values)[iter] = ebitmap_get_bit(&policydb.policycaps, iter);
+ *len = POLICYDB_CAPABILITY_MAX;
+
+out:
+ POLICY_RDUNLOCK;
+ return rc;
+}
+
+/**
+ * security_policycap_supported - Check for a specific policy capability
+ * @req_cap: capability
+ *
+ * Description:
+ * This function queries the currently loaded policy to see if it supports the
+ * capability specified by @req_cap. Returns true (1) if the capability is
+ * supported, false (0) if it isn't supported.
+ *
+ */
+int security_policycap_supported(unsigned int req_cap)
+{
+ int rc;
+
+ POLICY_RDLOCK;
+ rc = ebitmap_get_bit(&policydb.policycaps, req_cap);
+ POLICY_RDUNLOCK;
+
+ return rc;
+}
+
struct selinux_audit_rule {
u32 au_seqno;
struct context au_ctxt;