[PATCH] tpm: add bios measurement log

According to the TCG specifications measurements or hashes of the BIOS code
and data are extended into TPM PCRS and a log is kept in an ACPI table of
these extensions for later validation if desired.  This patch exports the
values in the ACPI table through a security-fs seq_file.

Signed-off-by: Seiji Munetoh <munetoh@jp.ibm.com>
Signed-off-by: Stefan Berger <stefanb@us.ibm.com>
Signed-off-by: Reiner Sailer <sailer@us.ibm.com>
Signed-off-by: Kylene Hall <kjhall@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Author: Kylene Jo Hall

drivers/acpi/osl.c

@@ -204,11 +204,13 @@ acpi_os_map_memory(acpi_physical_address phys, acpi_size size,
 
 	return AE_OK;
 }
+EXPORT_SYMBOL_GPL(acpi_os_map_memory);
 
 void acpi_os_unmap_memory(void __iomem * virt, acpi_size size)
 {
 	iounmap(virt);
 }
+EXPORT_SYMBOL_GPL(acpi_os_unmap_memory);
 
 #ifdef ACPI_FUTURE_USAGE
 acpi_status

drivers/char/tpm/Makefile

@@ -2,6 +2,9 @@
 # Makefile for the kernel tpm device drivers.
 #
 obj-$(CONFIG_TCG_TPM) += tpm.o
+ifdef CONFIG_ACPI
+	obj-$(CONFIG_TCG_TPM) += tpm_bios.o
+endif
 obj-$(CONFIG_TCG_NSC) += tpm_nsc.o
 obj-$(CONFIG_TCG_ATMEL) += tpm_atmel.o
 obj-$(CONFIG_TCG_INFINEON) += tpm_infineon.o

drivers/char/tpm/tpm.c

@@ -466,6 +466,7 @@ void tpm_remove_hardware(struct device *dev)
 	kfree(chip->vendor->miscdev.name);
 
 	sysfs_remove_group(&dev->kobj, chip->vendor->attr_group);
+	tpm_bios_log_teardown(chip->bios_dir);
 
 	dev_mask[chip->dev_num / TPM_NUM_MASK_ENTRIES ] &=
 		~(1 << (chip->dev_num % TPM_NUM_MASK_ENTRIES));
@@ -593,6 +594,8 @@ int tpm_register_hardware(struct device *dev, struct tpm_vendor_specific *entry)
 
 	sysfs_create_group(&dev->kobj, chip->vendor->attr_group);
 
+	chip->bios_dir = tpm_bios_log_setup(devname);
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(tpm_register_hardware);

drivers/char/tpm/tpm.h

@@ -82,6 +82,8 @@ struct tpm_chip {
 
 	struct tpm_vendor_specific *vendor;
 
+	struct dentry **bios_dir;
+
 	struct list_head list;
 };
 
@@ -107,3 +109,16 @@ extern ssize_t tpm_read(struct file *, char __user *, size_t, loff_t *);
 extern void tpm_remove_hardware(struct device *);
 extern int tpm_pm_suspend(struct device *, pm_message_t);
 extern int tpm_pm_resume(struct device *);
+
+#ifdef CONFIG_ACPI
+extern struct dentry ** tpm_bios_log_setup(char *);
+extern void tpm_bios_log_teardown(struct dentry **);
+#else
+static inline struct dentry* tpm_bios_log_setup(char *name)
+{
+	return NULL;
+}
+static inline void tpm_bios_log_teardown(struct dentry **dir)
+{
+}
+#endif