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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/char/tpm/eventlog/acpi.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/char/tpm/eventlog/acpi.c')
-rw-r--r--drivers/char/tpm/eventlog/acpi.c170
1 files changed, 170 insertions, 0 deletions
diff --git a/drivers/char/tpm/eventlog/acpi.c b/drivers/char/tpm/eventlog/acpi.c
new file mode 100644
index 000000000..cd266021d
--- /dev/null
+++ b/drivers/char/tpm/eventlog/acpi.c
@@ -0,0 +1,170 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2005 IBM Corporation
+ *
+ * Authors:
+ * Seiji Munetoh <munetoh@jp.ibm.com>
+ * Stefan Berger <stefanb@us.ibm.com>
+ * Reiner Sailer <sailer@watson.ibm.com>
+ * Kylene Hall <kjhall@us.ibm.com>
+ * Nayna Jain <nayna@linux.vnet.ibm.com>
+ *
+ * Maintained by: <tpmdd-devel@lists.sourceforge.net>
+ *
+ * Access to the event log extended by the TCG BIOS of PC platform
+ */
+
+#include <linux/seq_file.h>
+#include <linux/fs.h>
+#include <linux/security.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/acpi.h>
+#include <linux/tpm_eventlog.h>
+
+#include "../tpm.h"
+#include "common.h"
+
+struct acpi_tcpa {
+ struct acpi_table_header hdr;
+ u16 platform_class;
+ union {
+ struct client_hdr {
+ u32 log_max_len __packed;
+ u64 log_start_addr __packed;
+ } client;
+ struct server_hdr {
+ u16 reserved;
+ u64 log_max_len __packed;
+ u64 log_start_addr __packed;
+ } server;
+ };
+};
+
+/* Check that the given log is indeed a TPM2 log. */
+static bool tpm_is_tpm2_log(void *bios_event_log, u64 len)
+{
+ struct tcg_efi_specid_event_head *efispecid;
+ struct tcg_pcr_event *event_header;
+ int n;
+
+ if (len < sizeof(*event_header))
+ return false;
+ len -= sizeof(*event_header);
+ event_header = bios_event_log;
+
+ if (len < sizeof(*efispecid))
+ return false;
+ efispecid = (struct tcg_efi_specid_event_head *)event_header->event;
+
+ n = memcmp(efispecid->signature, TCG_SPECID_SIG,
+ sizeof(TCG_SPECID_SIG));
+ return n == 0;
+}
+
+/* read binary bios log */
+int tpm_read_log_acpi(struct tpm_chip *chip)
+{
+ struct acpi_tcpa *buff;
+ acpi_status status;
+ void __iomem *virt;
+ u64 len, start;
+ struct tpm_bios_log *log;
+ struct acpi_table_tpm2 *tbl;
+ struct acpi_tpm2_phy *tpm2_phy;
+ int format;
+ int ret;
+
+ log = &chip->log;
+
+ /* Unfortuntely ACPI does not associate the event log with a specific
+ * TPM, like PPI. Thus all ACPI TPMs will read the same log.
+ */
+ if (!chip->acpi_dev_handle)
+ return -ENODEV;
+
+ if (chip->flags & TPM_CHIP_FLAG_TPM2) {
+ status = acpi_get_table("TPM2", 1,
+ (struct acpi_table_header **)&tbl);
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ if (tbl->header.length <
+ sizeof(*tbl) + sizeof(struct acpi_tpm2_phy)) {
+ acpi_put_table((struct acpi_table_header *)tbl);
+ return -ENODEV;
+ }
+
+ tpm2_phy = (void *)tbl + sizeof(*tbl);
+ len = tpm2_phy->log_area_minimum_length;
+
+ start = tpm2_phy->log_area_start_address;
+ if (!start || !len) {
+ acpi_put_table((struct acpi_table_header *)tbl);
+ return -ENODEV;
+ }
+
+ acpi_put_table((struct acpi_table_header *)tbl);
+ format = EFI_TCG2_EVENT_LOG_FORMAT_TCG_2;
+ } else {
+ /* Find TCPA entry in RSDT (ACPI_LOGICAL_ADDRESSING) */
+ status = acpi_get_table(ACPI_SIG_TCPA, 1,
+ (struct acpi_table_header **)&buff);
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ switch (buff->platform_class) {
+ case BIOS_SERVER:
+ len = buff->server.log_max_len;
+ start = buff->server.log_start_addr;
+ break;
+ case BIOS_CLIENT:
+ default:
+ len = buff->client.log_max_len;
+ start = buff->client.log_start_addr;
+ break;
+ }
+
+ acpi_put_table((struct acpi_table_header *)buff);
+ format = EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2;
+ }
+
+ if (!len) {
+ dev_warn(&chip->dev, "%s: TCPA log area empty\n", __func__);
+ return -EIO;
+ }
+
+ /* malloc EventLog space */
+ log->bios_event_log = kmalloc(len, GFP_KERNEL);
+ if (!log->bios_event_log)
+ return -ENOMEM;
+
+ log->bios_event_log_end = log->bios_event_log + len;
+
+ ret = -EIO;
+ virt = acpi_os_map_iomem(start, len);
+ if (!virt) {
+ dev_warn(&chip->dev, "%s: Failed to map ACPI memory\n", __func__);
+ /* try EFI log next */
+ ret = -ENODEV;
+ goto err;
+ }
+
+ memcpy_fromio(log->bios_event_log, virt, len);
+
+ acpi_os_unmap_iomem(virt, len);
+
+ if (chip->flags & TPM_CHIP_FLAG_TPM2 &&
+ !tpm_is_tpm2_log(log->bios_event_log, len)) {
+ /* try EFI log next */
+ ret = -ENODEV;
+ goto err;
+ }
+
+ return format;
+
+err:
+ kfree(log->bios_event_log);
+ log->bios_event_log = NULL;
+ return ret;
+}