[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[PATCH v2 2/2] flask: implement xsm_transtion_running


  • To: xen-devel@xxxxxxxxxxxxxxxxxxxx, "Daniel P. Smith" <dpsmith@xxxxxxxxxxxxxxxxxxxx>
  • From: "Daniel P. Smith" <dpsmith@xxxxxxxxxxxxxxxxxxxx>
  • Date: Wed, 20 Apr 2022 18:28:34 -0400
  • Arc-authentication-results: i=1; mx.zohomail.com; dkim=pass header.i=apertussolutions.com; spf=pass smtp.mailfrom=dpsmith@xxxxxxxxxxxxxxxxxxxx; dmarc=pass header.from=<dpsmith@xxxxxxxxxxxxxxxxxxxx>
  • Arc-message-signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1650493730; h=Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:To; bh=rHJBVfL0hECCWnf5o+DbpSbD0YLUZ/xJtca9sdXcG1M=; b=ayMfG5enGgHrnHUImdpGE3OWHYaY+CIcxc5/9xTaROf4CxL0SW2n6eo50JTnBdvIvCqRrmduftJxkdcdj0Dg/GckZfXlPCTnpB9Z4Mib6xaobXpbmTqpvPMB7sNAX+3QNK3sYuokzs/83zZbjSa4BZSdyweGRDpeNo2oN0bWISs=
  • Arc-seal: i=1; a=rsa-sha256; t=1650493730; cv=none; d=zohomail.com; s=zohoarc; b=iuJcKq+ndj+QWhAzGfa0ETYdjBS9od22RVIYMRfUNU6z7UgC3FyBj/5xHaDoKyYsdZqD6MjRvkBUcAyvVVHDG1sFJ8l5WFcyEoPb7GzEvMjA9GCxcOHiiJSrOqyxuR+f543abUHowW+Gb+ckXZd4uY/MCJMHnfOCpM/owKnXbcs=
  • Cc: scott.davis@xxxxxxxxxx, jandryuk@xxxxxxxxx, Daniel De Graaf <dgdegra@xxxxxxxxxxxxx>, Wei Liu <wl@xxxxxxx>, Anthony PERARD <anthony.perard@xxxxxxxxxx>
  • Delivery-date: Wed, 20 Apr 2022 22:29:18 +0000
  • List-id: Xen developer discussion <xen-devel.lists.xenproject.org>

This commit implements full support for starting the idle domain privileged by
introducing a new flask label xenboot_t which the idle domain is labeled with
at creation.  It then provides the implementation for the XSM hook
xsm_transition_running to relabel the idle domain to the existing xen_t flask
label.

In the reference flask policy a new macro, xen_build_domain(target), is
introduced for creating policies for dom0less/hyperlaunch allowing the
hypervisor to create and assign the necessary resources for domain
construction.

Signed-off-by: Daniel P. Smith <dpsmith@xxxxxxxxxxxxxxxxxxxx>
---
 tools/flask/policy/modules/xen.if      | 6 ++++++
 tools/flask/policy/modules/xen.te      | 1 +
 tools/flask/policy/policy/initial_sids | 1 +
 xen/xsm/flask/hooks.c                  | 7 ++++++-
 xen/xsm/flask/policy/initial_sids      | 1 +
 5 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/tools/flask/policy/modules/xen.if 
b/tools/flask/policy/modules/xen.if
index 5e2aa472b6..4ec676fff1 100644
--- a/tools/flask/policy/modules/xen.if
+++ b/tools/flask/policy/modules/xen.if
@@ -62,6 +62,12 @@ define(`create_domain_common', `
                        setparam altp2mhvm altp2mhvm_op dm };
 ')
 
+# xen_build_domain(target)
+#   Allow a domain to be created at boot by the hypervisor
+define(`xen_build_domain', `
+       allow xenboot_t $1_channel:event create;
+')
+
 # create_domain(priv, target)
 #   Allow a domain to be created directly
 define(`create_domain', `
diff --git a/tools/flask/policy/modules/xen.te 
b/tools/flask/policy/modules/xen.te
index 3dbf93d2b8..de98206fdd 100644
--- a/tools/flask/policy/modules/xen.te
+++ b/tools/flask/policy/modules/xen.te
@@ -24,6 +24,7 @@ attribute mls_priv;
 
################################################################################
 
 # The hypervisor itself
+type xenboot_t, xen_type, mls_priv;
 type xen_t, xen_type, mls_priv;
 
 # Domain 0
diff --git a/tools/flask/policy/policy/initial_sids 
b/tools/flask/policy/policy/initial_sids
index 6b7b7eff21..ec729d3ba3 100644
--- a/tools/flask/policy/policy/initial_sids
+++ b/tools/flask/policy/policy/initial_sids
@@ -2,6 +2,7 @@
 # objects created before the policy is loaded or for objects that do not have a
 # label defined in some other manner.
 
+sid xenboot gen_context(system_u:system_r:xenboot_t,s0)
 sid xen gen_context(system_u:system_r:xen_t,s0)
 sid dom0 gen_context(system_u:system_r:dom0_t,s0)
 sid domxen gen_context(system_u:system_r:domxen_t,s0)
diff --git a/xen/xsm/flask/hooks.c b/xen/xsm/flask/hooks.c
index decebc8231..0643654aba 100644
--- a/xen/xsm/flask/hooks.c
+++ b/xen/xsm/flask/hooks.c
@@ -168,7 +168,7 @@ static int cf_check flask_domain_alloc_security(struct 
domain *d)
     switch ( d->domain_id )
     {
     case DOMID_IDLE:
-        dsec->sid = SECINITSID_XEN;
+        dsec->sid = SECINITSID_XENBOOT;
         break;
     case DOMID_XEN:
         dsec->sid = SECINITSID_DOMXEN;
@@ -188,6 +188,7 @@ static int cf_check flask_domain_alloc_security(struct 
domain *d)
 
 static void cf_check flask_transition_running(void)
 {
+    struct domain_security_struct *dsec;
     struct domain *d = current->domain;
 
     if ( d->domain_id != DOMID_IDLE )
@@ -198,6 +199,10 @@ static void cf_check flask_transition_running(void)
      * set to false for the consistency check(s) in the setup code.
      */
     d->is_privileged = false;
+
+    dsec = d->ssid;
+    dsec->sid = SECINITSID_XEN;
+    dsec->self_sid = dsec->sid;
 }
 
 static void cf_check flask_domain_free_security(struct domain *d)
diff --git a/xen/xsm/flask/policy/initial_sids 
b/xen/xsm/flask/policy/initial_sids
index 7eca70d339..e8b55b8368 100644
--- a/xen/xsm/flask/policy/initial_sids
+++ b/xen/xsm/flask/policy/initial_sids
@@ -3,6 +3,7 @@
 #
 # Define initial security identifiers 
 #
+sid xenboot
 sid xen
 sid dom0
 sid domio
-- 
2.20.1




 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.