x86, intel_txt: Intel TXT boot support

This patch adds kernel configuration and boot support for Intel Trusted
Execution Technology (Intel TXT).

Intel's technology for safer computing, Intel Trusted Execution
Technology (Intel TXT), defines platform-level enhancements that
provide the building blocks for creating trusted platforms.

Intel TXT was formerly known by the code name LaGrande Technology (LT).

Intel TXT in Brief:
o  Provides dynamic root of trust for measurement (DRTM)
o  Data protection in case of improper shutdown
o  Measurement and verification of launched environment

Intel TXT is part of the vPro(TM) brand and is also available some
non-vPro systems.  It is currently available on desktop systems based on
the Q35, X38, Q45, and Q43 Express chipsets (e.g. Dell Optiplex 755, HP
dc7800, etc.) and mobile systems based on the GM45, PM45, and GS45
Express chipsets.

For more information, see http://www.intel.com/technology/security/.
This site also has a link to the Intel TXT MLE Developers Manual, which
has been updated for the new released platforms.

A much more complete description of how these patches support TXT, how to
configure a system for it, etc. is in the Documentation/intel_txt.txt file
in this patch.

This patch provides the TXT support routines for complete functionality,
documentation for TXT support and for the changes to the boot_params structure,
and boot detection of a TXT launch.  Attempts to shutdown (reboot, Sx) the system
will result in platform resets; subsequent patches will support these shutdown modes
properly.

 Documentation/intel_txt.txt      |  210 +++++++++++++++++++++
 Documentation/x86/zero-page.txt  |    1
 arch/x86/include/asm/bootparam.h |    3
 arch/x86/include/asm/fixmap.h    |    3
 arch/x86/include/asm/tboot.h     |  197 ++++++++++++++++++++
 arch/x86/kernel/Makefile         |    1
 arch/x86/kernel/setup.c          |    4
 arch/x86/kernel/tboot.c          |  379 +++++++++++++++++++++++++++++++++++++++
 security/Kconfig                 |   30 +++
 9 files changed, 827 insertions(+), 1 deletion(-)

Signed-off-by: Joseph Cihula <joseph.cihula@intel.com>
Signed-off-by: Shane Wang <shane.wang@intel.com>
Signed-off-by: Gang Wei <gang.wei@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

3 files changed, 202 insertions, 1 deletions

diff --git a/arch/x86/include/asm/bootparam.h b/arch/x86/include/asm/bootparam.h
index 1724e8de317c..6ca20218dd72 100644
--- a/arch/x86/include/asm/bootparam.h
+++ b/arch/x86/include/asm/bootparam.h
@@ -85,7 +85,8 @@ struct efi_info {
 struct boot_params {
         struct screen_info screen_info;                 /* 0x000 */
         struct apm_bios_info apm_bios_info;             /* 0x040 */
-        __u8  _pad2[12];                                /* 0x054 */
+        __u8  _pad2[4];                                 /* 0x054 */
+        __u64  tboot_addr;                              /* 0x058 */
         struct ist_info ist_info;                       /* 0x060 */
         __u8  _pad3[16];                                /* 0x070 */
         __u8  hd0_info[16];     /* obsolete! */         /* 0x080 */
diff --git a/arch/x86/include/asm/fixmap.h b/arch/x86/include/asm/fixmap.h
index 7b2d71df39a6..14f9890eb495 100644
--- a/arch/x86/include/asm/fixmap.h
+++ b/arch/x86/include/asm/fixmap.h
@@ -132,6 +132,9 @@ enum fixed_addresses {
 #ifdef CONFIG_X86_32
         FIX_WP_TEST,
 #endif
+#ifdef CONFIG_INTEL_TXT
+        FIX_TBOOT_BASE,
+#endif
         __end_of_fixed_addresses
 };
 
diff --git a/arch/x86/include/asm/tboot.h b/arch/x86/include/asm/tboot.h
new file mode 100644
index 000000000000..b13929d4e5f4
--- /dev/null
+++ b/arch/x86/include/asm/tboot.h
@@ -0,0 +1,197 @@
+/*
+ * tboot.h: shared data structure with tboot and kernel and functions
+ *          used by kernel for runtime support of Intel(R) Trusted
+ *          Execution Technology
+ *
+ * Copyright (c) 2006-2009, Intel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#ifndef _ASM_TBOOT_H
+#define _ASM_TBOOT_H
+
+#include <acpi/acpi.h>
+
+/* these must have the values from 0-5 in this order */
+enum {
+        TB_SHUTDOWN_REBOOT = 0,
+        TB_SHUTDOWN_S5,
+        TB_SHUTDOWN_S4,
+        TB_SHUTDOWN_S3,
+        TB_SHUTDOWN_HALT,
+        TB_SHUTDOWN_WFS
+};
+
+#ifdef CONFIG_INTEL_TXT
+
+/* used to communicate between tboot and the launched kernel */
+
+#define TB_KEY_SIZE             64   /* 512 bits */
+
+#define MAX_TB_MAC_REGIONS      32
+
+struct tboot_mac_region {
+        u64  start;         /* must be 64 byte -aligned */
+        u32  size;          /* must be 64 byte -granular */
+} __packed;
+
+/* GAS - Generic Address Structure (ACPI 2.0+) */
+struct tboot_acpi_generic_address {
+        u8  space_id;
+        u8  bit_width;
+        u8  bit_offset;
+        u8  access_width;
+        u64 address;
+} __packed;
+
+/*
+ * combines Sx info from FADT and FACS tables per ACPI 2.0+ spec
+ * (http://www.acpi.info/)
+ */
+struct tboot_acpi_sleep_info {
+        struct tboot_acpi_generic_address pm1a_cnt_blk;
+        struct tboot_acpi_generic_address pm1b_cnt_blk;
+        struct tboot_acpi_generic_address pm1a_evt_blk;
+        struct tboot_acpi_generic_address pm1b_evt_blk;
+        u16 pm1a_cnt_val;
+        u16 pm1b_cnt_val;
+        u64 wakeup_vector;
+        u32 vector_width;
+        u64 kernel_s3_resume_vector;
+} __packed;
+
+/*
+ * shared memory page used for communication between tboot and kernel
+ */
+struct tboot {
+        /*
+         * version 3+ fields:
+         */
+
+        /* TBOOT_UUID */
+        u8 uuid[16];
+
+        /* version number: 5 is current */
+        u32 version;
+
+        /* physical addr of tb_log_t log */
+        u32 log_addr;
+
+        /*
+         * physical addr of entry point for tboot shutdown and
+         * type of shutdown (TB_SHUTDOWN_*) being requested
+         */
+        u32 shutdown_entry;
+        u32 shutdown_type;
+
+        /* kernel-specified ACPI info for Sx shutdown */
+        struct tboot_acpi_sleep_info acpi_sinfo;
+
+        /* tboot location in memory (physical) */
+        u32 tboot_base;
+        u32 tboot_size;
+
+        /* memory regions (phys addrs) for tboot to MAC on S3 */
+        u8 num_mac_regions;
+        struct tboot_mac_region mac_regions[MAX_TB_MAC_REGIONS];
+
+
+        /*
+         * version 4+ fields:
+         */
+
+        /* symmetric key for use by kernel; will be encrypted on S3 */
+        u8 s3_key[TB_KEY_SIZE];
+
+
+        /*
+         * version 5+ fields:
+         */
+
+        /* used to 4byte-align num_in_wfs */
+        u8 reserved_align[3];
+
+        /* number of processors in wait-for-SIPI */
+        u32 num_in_wfs;
+} __packed;
+
+/*
+ * UUID for tboot data struct to facilitate matching
+ * defined as {663C8DFF-E8B3-4b82-AABF-19EA4D057A08} by tboot, which is
+ * represented as {} in the char array used here
+ */
+#define TBOOT_UUID      {0xff, 0x8d, 0x3c, 0x66, 0xb3, 0xe8, 0x82, 0x4b, 0xbf,\
+                         0xaa, 0x19, 0xea, 0x4d, 0x5, 0x7a, 0x8}
+
+extern struct tboot *tboot;
+
+static inline int tboot_enabled(void)
+{
+        return tboot != NULL;
+}
+
+extern void tboot_probe(void);
+extern void tboot_create_trampoline(void);
+extern void tboot_shutdown(u32 shutdown_type);
+extern void tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control);
+extern int tboot_wait_for_aps(int num_aps);
+extern struct acpi_table_header *tboot_get_dmar_table(
+                                      struct acpi_table_header *dmar_tbl);
+extern int tboot_force_iommu(void);
+
+#else     /* CONFIG_INTEL_TXT */
+
+static inline int tboot_enabled(void)
+{
+        return 0;
+}
+
+static inline void tboot_probe(void)
+{
+}
+
+static inline void tboot_create_trampoline(void)
+{
+}
+
+static inline void tboot_shutdown(u32 shutdown_type)
+{
+}
+
+static inline void tboot_sleep(u8 sleep_state, u32 pm1a_control,
+                               u32 pm1b_control)
+{
+}
+
+static inline int tboot_wait_for_aps(int num_aps)
+{
+        return 0;
+}
+
+static inline struct acpi_table_header *tboot_get_dmar_table(
+                                        struct acpi_table_header *dmar_tbl)
+{
+        return dmar_tbl;
+}
+
+static inline int tboot_force_iommu(void)
+{
+        return 0;
+}
+
+#endif /* !CONFIG_INTEL_TXT */
+
+#endif /* _ASM_TBOOT_H */