1 files changed, 389 insertions, 0 deletions

diff --git a/drivers/char/tpm/tpm_ppi.c b/drivers/char/tpm/tpm_ppi.c
new file mode 100644
index 000000000..b2dab941c
--- /dev/null
+++ b/drivers/char/tpm/tpm_ppi.c
@@ -0,0 +1,389 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2012-2014 Intel Corporation
+ *
+ * Authors:
+ * Xiaoyan Zhang <xiaoyan.zhang@intel.com>
+ * Jiang Liu <jiang.liu@linux.intel.com>
+ * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
+ *
+ * Maintained by: <tpmdd-devel@lists.sourceforge.net>
+ *
+ * This file contains implementation of the sysfs interface for PPI.
+ */
+
+
+#include <linux/acpi.h>
+#include "tpm.h"
+
+#define TPM_PPI_REVISION_ID_1	1
+#define TPM_PPI_REVISION_ID_2	2
+#define TPM_PPI_FN_VERSION	1
+#define TPM_PPI_FN_SUBREQ	2
+#define TPM_PPI_FN_GETREQ	3
+#define TPM_PPI_FN_GETACT	4
+#define TPM_PPI_FN_GETRSP	5
+#define TPM_PPI_FN_SUBREQ2	7
+#define TPM_PPI_FN_GETOPR	8
+#define PPI_TPM_REQ_MAX		101 /* PPI 1.3 for TPM 2 */
+#define PPI_VS_REQ_START	128
+#define PPI_VS_REQ_END		255
+
+static const guid_t tpm_ppi_guid =
+	GUID_INIT(0x3DDDFAA6, 0x361B, 0x4EB4,
+		  0xA4, 0x24, 0x8D, 0x10, 0x08, 0x9D, 0x16, 0x53);
+
+static bool tpm_ppi_req_has_parameter(u64 req)
+{
+	return req == 23;
+}
+
+static inline union acpi_object *
+tpm_eval_dsm(acpi_handle ppi_handle, int func, acpi_object_type type,
+	     union acpi_object *argv4, u64 rev)
+{
+	BUG_ON(!ppi_handle);
+	return acpi_evaluate_dsm_typed(ppi_handle, &tpm_ppi_guid,
+				       rev, func, argv4, type);
+}
+
+static ssize_t tpm_show_ppi_version(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct tpm_chip *chip = to_tpm_chip(dev);
+
+	return scnprintf(buf, PAGE_SIZE, "%s\n", chip->ppi_version);
+}
+
+static ssize_t tpm_show_ppi_request(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	ssize_t size = -EINVAL;
+	union acpi_object *obj;
+	struct tpm_chip *chip = to_tpm_chip(dev);
+	u64 rev = TPM_PPI_REVISION_ID_2;
+	u64 req;
+
+	if (strcmp(chip->ppi_version, "1.2") < 0)
+		rev = TPM_PPI_REVISION_ID_1;
+
+	obj = tpm_eval_dsm(chip->acpi_dev_handle, TPM_PPI_FN_GETREQ,
+			   ACPI_TYPE_PACKAGE, NULL, rev);
+	if (!obj)
+		return -ENXIO;
+
+	/*
+	 * output.pointer should be of package type, including two integers.
+	 * The first is function return code, 0 means success and 1 means
+	 * error. The second is pending TPM operation requested by the OS, 0
+	 * means none and >0 means operation value.
+	 */
+	if (obj->package.count == 3 &&
+	    obj->package.elements[0].type == ACPI_TYPE_INTEGER &&
+	    obj->package.elements[1].type == ACPI_TYPE_INTEGER &&
+	    obj->package.elements[2].type == ACPI_TYPE_INTEGER) {
+		if (obj->package.elements[0].integer.value)
+			size = -EFAULT;
+		else {
+			req = obj->package.elements[1].integer.value;
+			if (tpm_ppi_req_has_parameter(req))
+				size = scnprintf(buf, PAGE_SIZE,
+				    "%llu %llu\n", req,
+				    obj->package.elements[2].integer.value);
+			else
+				size = scnprintf(buf, PAGE_SIZE,
+						"%llu\n", req);
+		}
+	} else if (obj->package.count == 2 &&
+	    obj->package.elements[0].type == ACPI_TYPE_INTEGER &&
+	    obj->package.elements[1].type == ACPI_TYPE_INTEGER) {
+		if (obj->package.elements[0].integer.value)
+			size = -EFAULT;
+		else
+			size = scnprintf(buf, PAGE_SIZE, "%llu\n",
+				 obj->package.elements[1].integer.value);
+	}
+
+	ACPI_FREE(obj);
+
+	return size;
+}
+
+static ssize_t tpm_store_ppi_request(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf, size_t count)
+{
+	u32 req;
+	u64 ret;
+	int func = TPM_PPI_FN_SUBREQ;
+	union acpi_object *obj, tmp[2];
+	union acpi_object argv4 = ACPI_INIT_DSM_ARGV4(2, tmp);
+	struct tpm_chip *chip = to_tpm_chip(dev);
+	u64 rev = TPM_PPI_REVISION_ID_1;
+
+	/*
+	 * the function to submit TPM operation request to pre-os environment
+	 * is updated with function index from SUBREQ to SUBREQ2 since PPI
+	 * version 1.1
+	 */
+	if (acpi_check_dsm(chip->acpi_dev_handle, &tpm_ppi_guid,
+			   TPM_PPI_REVISION_ID_1, 1 << TPM_PPI_FN_SUBREQ2))
+		func = TPM_PPI_FN_SUBREQ2;
+
+	/*
+	 * PPI spec defines params[3].type as ACPI_TYPE_PACKAGE. Some BIOS
+	 * accept buffer/string/integer type, but some BIOS accept buffer/
+	 * string/package type. For PPI version 1.0 and 1.1, use buffer type
+	 * for compatibility, and use package type since 1.2 according to spec.
+	 */
+	if (strcmp(chip->ppi_version, "1.3") == 0) {
+		if (sscanf(buf, "%llu %llu", &tmp[0].integer.value,
+			   &tmp[1].integer.value) != 2)
+			goto ppi12;
+		rev = TPM_PPI_REVISION_ID_2;
+		tmp[0].type = ACPI_TYPE_INTEGER;
+		tmp[1].type = ACPI_TYPE_INTEGER;
+	} else if (strcmp(chip->ppi_version, "1.2") < 0) {
+		if (sscanf(buf, "%d", &req) != 1)
+			return -EINVAL;
+		argv4.type = ACPI_TYPE_BUFFER;
+		argv4.buffer.length = sizeof(req);
+		argv4.buffer.pointer = (u8 *)&req;
+	} else {
+ppi12:
+		argv4.package.count = 1;
+		tmp[0].type = ACPI_TYPE_INTEGER;
+		if (sscanf(buf, "%llu", &tmp[0].integer.value) != 1)
+			return -EINVAL;
+	}
+
+	obj = tpm_eval_dsm(chip->acpi_dev_handle, func, ACPI_TYPE_INTEGER,
+			   &argv4, rev);
+	if (!obj) {
+		return -ENXIO;
+	} else {
+		ret = obj->integer.value;
+		ACPI_FREE(obj);
+	}
+
+	if (ret == 0)
+		return (acpi_status)count;
+
+	return (ret == 1) ? -EPERM : -EFAULT;
+}
+
+static ssize_t tpm_show_ppi_transition_action(struct device *dev,
+					      struct device_attribute *attr,
+					      char *buf)
+{
+	u32 ret;
+	acpi_status status;
+	union acpi_object *obj = NULL;
+	union acpi_object tmp = {
+		.buffer.type = ACPI_TYPE_BUFFER,
+		.buffer.length = 0,
+		.buffer.pointer = NULL
+	};
+	struct tpm_chip *chip = to_tpm_chip(dev);
+
+	static char *info[] = {
+		"None",
+		"Shutdown",
+		"Reboot",
+		"OS Vendor-specific",
+		"Error",
+	};
+
+	/*
+	 * PPI spec defines params[3].type as empty package, but some platforms
+	 * (e.g. Capella with PPI 1.0) need integer/string/buffer type, so for
+	 * compatibility, define params[3].type as buffer, if PPI version < 1.2
+	 */
+	if (strcmp(chip->ppi_version, "1.2") < 0)
+		obj = &tmp;
+	obj = tpm_eval_dsm(chip->acpi_dev_handle, TPM_PPI_FN_GETACT,
+			   ACPI_TYPE_INTEGER, obj, TPM_PPI_REVISION_ID_1);
+	if (!obj) {
+		return -ENXIO;
+	} else {
+		ret = obj->integer.value;
+		ACPI_FREE(obj);
+	}
+
+	if (ret < ARRAY_SIZE(info) - 1)
+		status = scnprintf(buf, PAGE_SIZE, "%d: %s\n", ret, info[ret]);
+	else
+		status = scnprintf(buf, PAGE_SIZE, "%d: %s\n", ret,
+				   info[ARRAY_SIZE(info)-1]);
+	return status;
+}
+
+static ssize_t tpm_show_ppi_response(struct device *dev,
+				     struct device_attribute *attr,
+				     char *buf)
+{
+	acpi_status status = -EINVAL;
+	union acpi_object *obj, *ret_obj;
+	u64 req, res;
+	struct tpm_chip *chip = to_tpm_chip(dev);
+
+	obj = tpm_eval_dsm(chip->acpi_dev_handle, TPM_PPI_FN_GETRSP,
+			   ACPI_TYPE_PACKAGE, NULL, TPM_PPI_REVISION_ID_1);
+	if (!obj)
+		return -ENXIO;
+
+	/*
+	 * parameter output.pointer should be of package type, including
+	 * 3 integers. The first means function return code, the second means
+	 * most recent TPM operation request, and the last means response to
+	 * the most recent TPM operation request. Only if the first is 0, and
+	 * the second integer is not 0, the response makes sense.
+	 */
+	ret_obj = obj->package.elements;
+	if (obj->package.count < 3 ||
+	    ret_obj[0].type != ACPI_TYPE_INTEGER ||
+	    ret_obj[1].type != ACPI_TYPE_INTEGER ||
+	    ret_obj[2].type != ACPI_TYPE_INTEGER)
+		goto cleanup;
+
+	if (ret_obj[0].integer.value) {
+		status = -EFAULT;
+		goto cleanup;
+	}
+
+	req = ret_obj[1].integer.value;
+	res = ret_obj[2].integer.value;
+	if (req) {
+		if (res == 0)
+			status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
+					   "0: Success");
+		else if (res == 0xFFFFFFF0)
+			status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
+					   "0xFFFFFFF0: User Abort");
+		else if (res == 0xFFFFFFF1)
+			status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
+					   "0xFFFFFFF1: BIOS Failure");
+		else if (res >= 1 && res <= 0x00000FFF)
+			status = scnprintf(buf, PAGE_SIZE, "%llu %llu: %s\n",
+					   req, res, "Corresponding TPM error");
+		else
+			status = scnprintf(buf, PAGE_SIZE, "%llu %llu: %s\n",
+					   req, res, "Error");
+	} else {
+		status = scnprintf(buf, PAGE_SIZE, "%llu: %s\n",
+				   req, "No Recent Request");
+	}
+
+cleanup:
+	ACPI_FREE(obj);
+	return status;
+}
+
+static ssize_t show_ppi_operations(acpi_handle dev_handle, char *buf, u32 start,
+				   u32 end)
+{
+	int i;
+	u32 ret;
+	char *str = buf;
+	union acpi_object *obj, tmp;
+	union acpi_object argv = ACPI_INIT_DSM_ARGV4(1, &tmp);
+
+	static char *info[] = {
+		"Not implemented",
+		"BIOS only",
+		"Blocked for OS by BIOS",
+		"User required",
+		"User not required",
+	};
+
+	if (!acpi_check_dsm(dev_handle, &tpm_ppi_guid, TPM_PPI_REVISION_ID_1,
+			    1 << TPM_PPI_FN_GETOPR))
+		return -EPERM;
+
+	tmp.integer.type = ACPI_TYPE_INTEGER;
+	for (i = start; i <= end; i++) {
+		tmp.integer.value = i;
+		obj = tpm_eval_dsm(dev_handle, TPM_PPI_FN_GETOPR,
+				   ACPI_TYPE_INTEGER, &argv,
+				   TPM_PPI_REVISION_ID_1);
+		if (!obj) {
+			return -ENOMEM;
+		} else {
+			ret = obj->integer.value;
+			ACPI_FREE(obj);
+		}
+
+		if (ret > 0 && ret < ARRAY_SIZE(info))
+			str += scnprintf(str, PAGE_SIZE, "%d %d: %s\n",
+					 i, ret, info[ret]);
+	}
+
+	return str - buf;
+}
+
+static ssize_t tpm_show_ppi_tcg_operations(struct device *dev,
+					   struct device_attribute *attr,
+					   char *buf)
+{
+	struct tpm_chip *chip = to_tpm_chip(dev);
+
+	return show_ppi_operations(chip->acpi_dev_handle, buf, 0,
+				   PPI_TPM_REQ_MAX);
+}
+
+static ssize_t tpm_show_ppi_vs_operations(struct device *dev,
+					  struct device_attribute *attr,
+					  char *buf)
+{
+	struct tpm_chip *chip = to_tpm_chip(dev);
+
+	return show_ppi_operations(chip->acpi_dev_handle, buf, PPI_VS_REQ_START,
+				   PPI_VS_REQ_END);
+}
+
+static DEVICE_ATTR(version, S_IRUGO, tpm_show_ppi_version, NULL);
+static DEVICE_ATTR(request, S_IRUGO | S_IWUSR | S_IWGRP,
+		   tpm_show_ppi_request, tpm_store_ppi_request);
+static DEVICE_ATTR(transition_action, S_IRUGO,
+		   tpm_show_ppi_transition_action, NULL);
+static DEVICE_ATTR(response, S_IRUGO, tpm_show_ppi_response, NULL);
+static DEVICE_ATTR(tcg_operations, S_IRUGO, tpm_show_ppi_tcg_operations, NULL);
+static DEVICE_ATTR(vs_operations, S_IRUGO, tpm_show_ppi_vs_operations, NULL);
+
+static struct attribute *ppi_attrs[] = {
+	&dev_attr_version.attr,
+	&dev_attr_request.attr,
+	&dev_attr_transition_action.attr,
+	&dev_attr_response.attr,
+	&dev_attr_tcg_operations.attr,
+	&dev_attr_vs_operations.attr, NULL,
+};
+static struct attribute_group ppi_attr_grp = {
+	.name = "ppi",
+	.attrs = ppi_attrs
+};
+
+void tpm_add_ppi(struct tpm_chip *chip)
+{
+	union acpi_object *obj;
+
+	if (!chip->acpi_dev_handle)
+		return;
+
+	if (!acpi_check_dsm(chip->acpi_dev_handle, &tpm_ppi_guid,
+			    TPM_PPI_REVISION_ID_1, 1 << TPM_PPI_FN_VERSION))
+		return;
+
+	/* Cache PPI version string. */
+	obj = acpi_evaluate_dsm_typed(chip->acpi_dev_handle, &tpm_ppi_guid,
+				      TPM_PPI_REVISION_ID_1,
+				      TPM_PPI_FN_VERSION,
+				      NULL, ACPI_TYPE_STRING);
+	if (obj) {
+		strlcpy(chip->ppi_version, obj->string.pointer,
+			sizeof(chip->ppi_version));
+		ACPI_FREE(obj);
+	}
+
+	chip->groups[chip->groups_cnt++] = &ppi_attr_grp;
+}