[go: nahoru, domu]
1/*
2 * Copyright (C) 2005 IBM Corporation
3 *
4 * Authors:
5 *	Seiji Munetoh <munetoh@jp.ibm.com>
6 *	Stefan Berger <stefanb@us.ibm.com>
7 *	Reiner Sailer <sailer@watson.ibm.com>
8 *	Kylene Hall <kjhall@us.ibm.com>
9 *
10 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
11 *
12 * Access to the eventlog extended by the TCG BIOS of PC platform
13 *
14 * This program is free software; you can redistribute it and/or
15 * modify it under the terms of the GNU General Public License
16 * as published by the Free Software Foundation; either version
17 * 2 of the License, or (at your option) any later version.
18 *
19 */
20
21#include <linux/seq_file.h>
22#include <linux/fs.h>
23#include <linux/security.h>
24#include <linux/module.h>
25#include <linux/slab.h>
26#include <linux/acpi.h>
27
28#include "tpm.h"
29#include "tpm_eventlog.h"
30
31struct acpi_tcpa {
32	struct acpi_table_header hdr;
33	u16 platform_class;
34	union {
35		struct client_hdr {
36			u32 log_max_len __packed;
37			u64 log_start_addr __packed;
38		} client;
39		struct server_hdr {
40			u16 reserved;
41			u64 log_max_len __packed;
42			u64 log_start_addr __packed;
43		} server;
44	};
45};
46
47/* read binary bios log */
48int read_log(struct tpm_bios_log *log)
49{
50	struct acpi_tcpa *buff;
51	acpi_status status;
52	void __iomem *virt;
53	u64 len, start;
54
55	if (log->bios_event_log != NULL) {
56		printk(KERN_ERR
57		       "%s: ERROR - Eventlog already initialized\n",
58		       __func__);
59		return -EFAULT;
60	}
61
62	/* Find TCPA entry in RSDT (ACPI_LOGICAL_ADDRESSING) */
63	status = acpi_get_table(ACPI_SIG_TCPA, 1,
64				(struct acpi_table_header **)&buff);
65
66	if (ACPI_FAILURE(status)) {
67		printk(KERN_ERR "%s: ERROR - Could not get TCPA table\n",
68		       __func__);
69		return -EIO;
70	}
71
72	switch(buff->platform_class) {
73	case BIOS_SERVER:
74		len = buff->server.log_max_len;
75		start = buff->server.log_start_addr;
76		break;
77	case BIOS_CLIENT:
78	default:
79		len = buff->client.log_max_len;
80		start = buff->client.log_start_addr;
81		break;
82	}
83	if (!len) {
84		printk(KERN_ERR "%s: ERROR - TCPA log area empty\n", __func__);
85		return -EIO;
86	}
87
88	/* malloc EventLog space */
89	log->bios_event_log = kmalloc(len, GFP_KERNEL);
90	if (!log->bios_event_log) {
91		printk("%s: ERROR - Not enough  Memory for BIOS measurements\n",
92			__func__);
93		return -ENOMEM;
94	}
95
96	log->bios_event_log_end = log->bios_event_log + len;
97
98	virt = acpi_os_map_iomem(start, len);
99	if (!virt) {
100		kfree(log->bios_event_log);
101		printk("%s: ERROR - Unable to map memory\n", __func__);
102		return -EIO;
103	}
104
105	memcpy_fromio(log->bios_event_log, virt, len);
106
107	acpi_os_unmap_iomem(virt, len);
108	return 0;
109}
110