/* * Copyright (C) 2012-2014 Intel Corporation * * Authors: * Xiaoyan Zhang * Jiang Liu * Jarkko Sakkinen * * Maintained by: * * This file contains implementation of the sysfs interface for PPI. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; version 2 * of the License. */ #include #include "tpm.h" #define TPM_PPI_REVISION_ID 1 #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 22 #define PPI_VS_REQ_START 128 #define PPI_VS_REQ_END 255 static const u8 tpm_ppi_uuid[] = { 0xA6, 0xFA, 0xDD, 0x3D, 0x1B, 0x36, 0xB4, 0x4E, 0xA4, 0x24, 0x8D, 0x10, 0x08, 0x9D, 0x16, 0x53 }; static inline union acpi_object * tpm_eval_dsm(acpi_handle ppi_handle, int func, acpi_object_type type, union acpi_object *argv4) { BUG_ON(!ppi_handle); return acpi_evaluate_dsm_typed(ppi_handle, tpm_ppi_uuid, TPM_PPI_REVISION_ID, func, argv4, type); } static ssize_t tpm_show_ppi_version(struct device *dev, struct device_attribute *attr, char *buf) { struct tpm_chip *chip = dev_get_drvdata(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 = dev_get_drvdata(dev); obj = tpm_eval_dsm(chip->acpi_dev_handle, TPM_PPI_FN_GETREQ, ACPI_TYPE_PACKAGE, NULL); 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 == 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; union acpi_object argv4 = ACPI_INIT_DSM_ARGV4(1, &tmp); struct tpm_chip *chip = dev_get_drvdata(dev); /* * 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_uuid, TPM_PPI_REVISION_ID, 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, "1.2") < 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 { tmp.type = ACPI_TYPE_INTEGER; if (sscanf(buf, "%llu", &tmp.integer.value) != 1) return -EINVAL; } obj = tpm_eval_dsm(chip->acpi_dev_handle, func, ACPI_TYPE_INTEGER, &argv4); 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 = dev_get_drvdata(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); 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 = dev_get_drvdata(dev); obj = tpm_eval_dsm(chip->acpi_dev_handle, TPM_PPI_FN_GETRSP, ACPI_TYPE_PACKAGE, NULL); 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_uuid, TPM_PPI_REVISION_ID, 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); 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 = dev_get_drvdata(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 = dev_get_drvdata(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 }; int tpm_add_ppi(struct tpm_chip *chip) { union acpi_object *obj; int rc; if (!chip->acpi_dev_handle) return 0; if (!acpi_check_dsm(chip->acpi_dev_handle, tpm_ppi_uuid, TPM_PPI_REVISION_ID, 1 << TPM_PPI_FN_VERSION)) return 0; /* Cache PPI version string. */ obj = acpi_evaluate_dsm_typed(chip->acpi_dev_handle, tpm_ppi_uuid, TPM_PPI_REVISION_ID, TPM_PPI_FN_VERSION, NULL, ACPI_TYPE_STRING); if (obj) { strlcpy(chip->ppi_version, obj->string.pointer, sizeof(chip->ppi_version)); ACPI_FREE(obj); } rc = sysfs_create_group(&chip->pdev->kobj, &ppi_attr_grp); if (!rc) chip->flags |= TPM_CHIP_FLAG_PPI; return rc; } void tpm_remove_ppi(struct tpm_chip *chip) { if (chip->flags & TPM_CHIP_FLAG_PPI) sysfs_remove_group(&chip->pdev->kobj, &ppi_attr_grp); }