[MLSXFRM]: Define new SELinux service routine
This defines a routine that combines the Type Enforcement portion of
one sid with the MLS portion from the other sid to arrive at a new
sid. This would be used to define a sid for a security association
that is to be negotiated by IKE as well as for determing the sid for
open requests and connection-oriented child sockets.
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index 85e4298..b00ec69 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -1817,6 +1817,75 @@
return rc;
}
+/*
+ * security_sid_mls_copy() - computes a new sid based on the given
+ * sid and the mls portion of mls_sid.
+ */
+int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
+{
+ struct context *context1;
+ struct context *context2;
+ struct context newcon;
+ char *s;
+ u32 len;
+ int rc = 0;
+
+ if (!ss_initialized) {
+ *new_sid = sid;
+ goto out;
+ }
+
+ context_init(&newcon);
+
+ POLICY_RDLOCK;
+ context1 = sidtab_search(&sidtab, sid);
+ if (!context1) {
+ printk(KERN_ERR "security_sid_mls_copy: unrecognized SID "
+ "%d\n", sid);
+ rc = -EINVAL;
+ goto out_unlock;
+ }
+
+ context2 = sidtab_search(&sidtab, mls_sid);
+ if (!context2) {
+ printk(KERN_ERR "security_sid_mls_copy: unrecognized SID "
+ "%d\n", mls_sid);
+ rc = -EINVAL;
+ goto out_unlock;
+ }
+
+ newcon.user = context1->user;
+ newcon.role = context1->role;
+ newcon.type = context1->type;
+ rc = mls_copy_context(&newcon, context2);
+ if (rc)
+ goto out_unlock;
+
+
+ /* Check the validity of the new context. */
+ if (!policydb_context_isvalid(&policydb, &newcon)) {
+ rc = convert_context_handle_invalid_context(&newcon);
+ if (rc)
+ goto bad;
+ }
+
+ rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
+ goto out_unlock;
+
+bad:
+ if (!context_struct_to_string(&newcon, &s, &len)) {
+ audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
+ "security_sid_mls_copy: invalid context %s", s);
+ kfree(s);
+ }
+
+out_unlock:
+ POLICY_RDUNLOCK;
+ context_destroy(&newcon);
+out:
+ return rc;
+}
+
struct selinux_audit_rule {
u32 au_seqno;
struct context au_ctxt;