linux-kernel - [RFC v6][PATCH 2/4] intel_txt: Intel(R) TXT reboot/halt shutdown support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <4A4ACA66.2000706@intel.com>
Date:	Tue, 30 Jun 2009 19:31:02 -0700
From:	Joseph Cihula <joseph.cihula@...el.com>
To:	linux-kernel@...r.kernel.org, mingo@...e.hu, arjan@...ux.intel.com,
	hpa@...or.com, andi@...stfloor.org
CC:	chrisw@...s-sol.org, jmorris@...ei.org, jbeulich@...ell.com,
	peterm@...hat.com, joseph.cihula@...el.com, gang.wei@...el.com,
	shane.wang@...el.com
Subject: [RFC v6][PATCH 2/4] intel_txt: Intel(R) TXT reboot/halt shutdown
 support

Support for graceful handling of kernel reboots after an Intel(R) TXT launch.

Without this patch, attempting to reboot or halt the system will cause the
TXT hardware to lock memory upon system restart because the secrets-in-memory
flag that was set on launch was never cleared.  This will in turn cause BIOS
to execute a TXT Authenticated Code Module (ACM) that will scrub all of memory
and then unlock it.  Depending on the amount of memory in the system and its type,
this may take some time.

This patch creates a 1:1 address mapping to the tboot module and then calls back
into tboot so that it may properly and securely clean up system state and clear
the secrets-in-memory flag.  When it has completed these steps, the tboot module
will reboot or halt the system.


 arch/x86/kernel/reboot.c |    8 ++++++++
 init/main.c              |    3 +++
 2 files changed, 11 insertions(+)

Signed-off-by: Joseph Cihula <joseph.cihula@...el.com>
Signed-off-by: Shane Wang <shane.wang@...el.com>

---

diff -uprN -X linus-2.6.git-0629/Documentation/dontdiff linus-2.6.git-0629/arch/x86/kernel/reboot.c linus-2.6.git-0629-txt/arch/x86/kernel/reboot.c
--- linus-2.6.git-0629/arch/x86/kernel/reboot.c	2009-06-29 21:57:17.000000000 -0700
+++ linus-2.6.git-0629-txt/arch/x86/kernel/reboot.c	2009-06-30 16:00:28.000000000 -0700
@@ -24,6 +24,8 @@
 # include <asm/iommu.h>
 #endif
 
+#include <asm/tboot.h>
+
 /*
  * Power off function, if any
  */
@@ -460,6 +462,8 @@ static void native_machine_emergency_res
 	if (reboot_emergency)
 		emergency_vmx_disable_all();
 
+	tboot_shutdown(TB_SHUTDOWN_REBOOT);
+
 	/* Tell the BIOS if we want cold or warm reboot */
 	*((unsigned short *)__va(0x472)) = reboot_mode;
 
@@ -586,6 +590,8 @@ static void native_machine_halt(void)
 	/* stop other cpus and apics */
 	machine_shutdown();
 
+	tboot_shutdown(TB_SHUTDOWN_HALT);
+
 	/* stop this cpu */
 	stop_this_cpu(NULL);
 }
@@ -597,6 +603,8 @@ static void native_machine_power_off(voi
 			machine_shutdown();
 		pm_power_off();
 	}
+	/* a fallback in case there is no PM info available */
+	tboot_shutdown(TB_SHUTDOWN_HALT);
 }
 
 struct machine_ops machine_ops = {
diff -uprN -X linus-2.6.git-0629/Documentation/dontdiff linus-2.6.git-0629/init/main.c linus-2.6.git-0629-txt/init/main.c
--- linus-2.6.git-0629/init/main.c	2009-06-29 21:57:26.000000000 -0700
+++ linus-2.6.git-0629-txt/init/main.c	2009-06-29 22:23:07.000000000 -0700
@@ -73,6 +73,7 @@
 #include <asm/io.h>
 #include <asm/bugs.h>
 #include <asm/setup.h>
+#include <asm/tboot.h>
 #include <asm/sections.h>
 #include <asm/cacheflush.h>
 
@@ -715,6 +716,8 @@ asmlinkage void __init start_kernel(void
 
 	ftrace_init();
 
+	tboot_create_trampoline();
+
 	/* Do the rest non-__init'ed, we're now alive */
 	rest_init();
 }

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/