linux/drivers/char/tpm/tpm_bios.c

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/*
* 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>
*
* Maintained by: <tpmdd-devel@lists.sourceforge.net>
*
* Access to the eventlog extended by the TCG BIOS of PC platform
*
* 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; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <linux/seq_file.h>
#include <linux/fs.h>
#include <linux/security.h>
#include <linux/module.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#include <acpi/acpi.h>
#include "tpm.h"
#define TCG_EVENT_NAME_LEN_MAX 255
#define MAX_TEXT_EVENT 1000 /* Max event string length */
#define ACPI_TCPA_SIG "TCPA" /* 0x41504354 /'TCPA' */
enum bios_platform_class {
BIOS_CLIENT = 0x00,
BIOS_SERVER = 0x01,
};
struct tpm_bios_log {
void *bios_event_log;
void *bios_event_log_end;
};
struct acpi_tcpa {
struct acpi_table_header hdr;
u16 platform_class;
union {
struct client_hdr {
u32 log_max_len __attribute__ ((packed));
u64 log_start_addr __attribute__ ((packed));
} client;
struct server_hdr {
u16 reserved;
u64 log_max_len __attribute__ ((packed));
u64 log_start_addr __attribute__ ((packed));
} server;
};
};
struct tcpa_event {
u32 pcr_index;
u32 event_type;
u8 pcr_value[20]; /* SHA1 */
u32 event_size;
u8 event_data[0];
};
enum tcpa_event_types {
PREBOOT = 0,
POST_CODE,
UNUSED,
NO_ACTION,
SEPARATOR,
ACTION,
EVENT_TAG,
SCRTM_CONTENTS,
SCRTM_VERSION,
CPU_MICROCODE,
PLATFORM_CONFIG_FLAGS,
TABLE_OF_DEVICES,
COMPACT_HASH,
IPL,
IPL_PARTITION_DATA,
NONHOST_CODE,
NONHOST_CONFIG,
NONHOST_INFO,
};
static const char* tcpa_event_type_strings[] = {
"PREBOOT",
"POST CODE",
"",
"NO ACTION",
"SEPARATOR",
"ACTION",
"EVENT TAG",
"S-CRTM Contents",
"S-CRTM Version",
"CPU Microcode",
"Platform Config Flags",
"Table of Devices",
"Compact Hash",
"IPL",
"IPL Partition Data",
"Non-Host Code",
"Non-Host Config",
"Non-Host Info"
};
struct tcpa_pc_event {
u32 event_id;
u32 event_size;
u8 event_data[0];
};
enum tcpa_pc_event_ids {
SMBIOS = 1,
BIS_CERT,
POST_BIOS_ROM,
ESCD,
CMOS,
NVRAM,
OPTION_ROM_EXEC,
OPTION_ROM_CONFIG,
OPTION_ROM_MICROCODE = 10,
S_CRTM_VERSION,
S_CRTM_CONTENTS,
POST_CONTENTS,
HOST_TABLE_OF_DEVICES,
};
static const char* tcpa_pc_event_id_strings[] = {
"",
"SMBIOS",
"BIS Certificate",
"POST BIOS ",
"ESCD ",
"CMOS",
"NVRAM",
"Option ROM",
"Option ROM config",
"",
"Option ROM microcode ",
"S-CRTM Version",
"S-CRTM Contents ",
"POST Contents ",
"Table of Devices",
};
/* returns pointer to start of pos. entry of tcg log */
static void *tpm_bios_measurements_start(struct seq_file *m, loff_t *pos)
{
loff_t i;
struct tpm_bios_log *log = m->private;
void *addr = log->bios_event_log;
void *limit = log->bios_event_log_end;
struct tcpa_event *event;
/* read over *pos measurements */
for (i = 0; i < *pos; i++) {
event = addr;
if ((addr + sizeof(struct tcpa_event)) < limit) {
if (event->event_type == 0 && event->event_size == 0)
return NULL;
addr += sizeof(struct tcpa_event) + event->event_size;
}
}
/* now check if current entry is valid */
if ((addr + sizeof(struct tcpa_event)) >= limit)
return NULL;
event = addr;
if ((event->event_type == 0 && event->event_size == 0) ||
((addr + sizeof(struct tcpa_event) + event->event_size) >= limit))
return NULL;
return addr;
}
static void *tpm_bios_measurements_next(struct seq_file *m, void *v,
loff_t *pos)
{
struct tcpa_event *event = v;
struct tpm_bios_log *log = m->private;
void *limit = log->bios_event_log_end;
v += sizeof(struct tcpa_event) + event->event_size;
/* now check if current entry is valid */
if ((v + sizeof(struct tcpa_event)) >= limit)
return NULL;
event = v;
if (event->event_type == 0 && event->event_size == 0)
return NULL;
if ((event->event_type == 0 && event->event_size == 0) ||
((v + sizeof(struct tcpa_event) + event->event_size) >= limit))
return NULL;
(*pos)++;
return v;
}
static void tpm_bios_measurements_stop(struct seq_file *m, void *v)
{
}
static int get_event_name(char *dest, struct tcpa_event *event,
unsigned char * event_entry)
{
const char *name = "";
/* 41 so there is room for 40 data and 1 nul */
char data[41] = "";
int i, n_len = 0, d_len = 0;
struct tcpa_pc_event *pc_event;
switch(event->event_type) {
case PREBOOT:
case POST_CODE:
case UNUSED:
case NO_ACTION:
case SCRTM_CONTENTS:
case SCRTM_VERSION:
case CPU_MICROCODE:
case PLATFORM_CONFIG_FLAGS:
case TABLE_OF_DEVICES:
case COMPACT_HASH:
case IPL:
case IPL_PARTITION_DATA:
case NONHOST_CODE:
case NONHOST_CONFIG:
case NONHOST_INFO:
name = tcpa_event_type_strings[event->event_type];
n_len = strlen(name);
break;
case SEPARATOR:
case ACTION:
if (MAX_TEXT_EVENT > event->event_size) {
name = event_entry;
n_len = event->event_size;
}
break;
case EVENT_TAG:
pc_event = (struct tcpa_pc_event *)event_entry;
/* ToDo Row data -> Base64 */
switch (pc_event->event_id) {
case SMBIOS:
case BIS_CERT:
case CMOS:
case NVRAM:
case OPTION_ROM_EXEC:
case OPTION_ROM_CONFIG:
case S_CRTM_VERSION:
name = tcpa_pc_event_id_strings[pc_event->event_id];
n_len = strlen(name);
break;
/* hash data */
case POST_BIOS_ROM:
case ESCD:
case OPTION_ROM_MICROCODE:
case S_CRTM_CONTENTS:
case POST_CONTENTS:
name = tcpa_pc_event_id_strings[pc_event->event_id];
n_len = strlen(name);
for (i = 0; i < 20; i++)
d_len += sprintf(&data[2*i], "%02x",
pc_event->event_data[i]);
break;
default:
break;
}
default:
break;
}
return snprintf(dest, MAX_TEXT_EVENT, "[%.*s%.*s]",
n_len, name, d_len, data);
}
static int tpm_binary_bios_measurements_show(struct seq_file *m, void *v)
{
struct tcpa_event *event = v;
char *data = v;
int i;
for (i = 0; i < sizeof(struct tcpa_event) + event->event_size; i++)
seq_putc(m, data[i]);
return 0;
}
static int tpm_bios_measurements_release(struct inode *inode,
struct file *file)
{
struct seq_file *seq = file->private_data;
struct tpm_bios_log *log = seq->private;
if (log) {
kfree(log->bios_event_log);
kfree(log);
}
return seq_release(inode, file);
}
static int tpm_ascii_bios_measurements_show(struct seq_file *m, void *v)
{
int len = 0;
int i;
char *eventname;
struct tcpa_event *event = v;
unsigned char *event_entry =
(unsigned char *) (v + sizeof(struct tcpa_event));
eventname = kmalloc(MAX_TEXT_EVENT, GFP_KERNEL);
if (!eventname) {
printk(KERN_ERR "%s: ERROR - No Memory for event name\n ",
__func__);
return -EFAULT;
}
seq_printf(m, "%2d ", event->pcr_index);
/* 2nd: SHA1 */
for (i = 0; i < 20; i++)
seq_printf(m, "%02x", event->pcr_value[i]);
/* 3rd: event type identifier */
seq_printf(m, " %02x", event->event_type);
len += get_event_name(eventname, event, event_entry);
/* 4th: eventname <= max + \'0' delimiter */
seq_printf(m, " %s\n", eventname);
kfree(eventname);
return 0;
}
static const struct seq_operations tpm_ascii_b_measurments_seqops = {
.start = tpm_bios_measurements_start,
.next = tpm_bios_measurements_next,
.stop = tpm_bios_measurements_stop,
.show = tpm_ascii_bios_measurements_show,
};
static const struct seq_operations tpm_binary_b_measurments_seqops = {
.start = tpm_bios_measurements_start,
.next = tpm_bios_measurements_next,
.stop = tpm_bios_measurements_stop,
.show = tpm_binary_bios_measurements_show,
};
/* read binary bios log */
static int read_log(struct tpm_bios_log *log)
{
struct acpi_tcpa *buff;
acpi_status status;
struct acpi_table_header *virt;
u64 len, start;
if (log->bios_event_log != NULL) {
printk(KERN_ERR
"%s: ERROR - Eventlog already initialized\n",
__func__);
return -EFAULT;
}
/* 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)) {
printk(KERN_ERR "%s: ERROR - Could not get TCPA table\n",
__func__);
return -EIO;
}
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;
}
if (!len) {
printk(KERN_ERR "%s: ERROR - TCPA log area empty\n", __func__);
return -EIO;
}
/* malloc EventLog space */
log->bios_event_log = kmalloc(len, GFP_KERNEL);
if (!log->bios_event_log) {
printk("%s: ERROR - Not enough Memory for BIOS measurements\n",
__func__);
return -ENOMEM;
}
log->bios_event_log_end = log->bios_event_log + len;
virt = acpi_os_map_memory(start, len);
memcpy(log->bios_event_log, virt, len);
acpi_os_unmap_memory(virt, len);
return 0;
}
static int tpm_ascii_bios_measurements_open(struct inode *inode,
struct file *file)
{
int err;
struct tpm_bios_log *log;
struct seq_file *seq;
log = kzalloc(sizeof(struct tpm_bios_log), GFP_KERNEL);
if (!log)
return -ENOMEM;
if ((err = read_log(log)))
goto out_free;
/* now register seq file */
err = seq_open(file, &tpm_ascii_b_measurments_seqops);
if (!err) {
seq = file->private_data;
seq->private = log;
} else {
goto out_free;
}
out:
return err;
out_free:
kfree(log->bios_event_log);
kfree(log);
goto out;
}
static const struct file_operations tpm_ascii_bios_measurements_ops = {
.open = tpm_ascii_bios_measurements_open,
.read = seq_read,
.llseek = seq_lseek,
.release = tpm_bios_measurements_release,
};
static int tpm_binary_bios_measurements_open(struct inode *inode,
struct file *file)
{
int err;
struct tpm_bios_log *log;
struct seq_file *seq;
log = kzalloc(sizeof(struct tpm_bios_log), GFP_KERNEL);
if (!log)
return -ENOMEM;
if ((err = read_log(log)))
goto out_free;
/* now register seq file */
err = seq_open(file, &tpm_binary_b_measurments_seqops);
if (!err) {
seq = file->private_data;
seq->private = log;
} else {
goto out_free;
}
out:
return err;
out_free:
kfree(log->bios_event_log);
kfree(log);
goto out;
}
static const struct file_operations tpm_binary_bios_measurements_ops = {
.open = tpm_binary_bios_measurements_open,
.read = seq_read,
.llseek = seq_lseek,
.release = tpm_bios_measurements_release,
};
static int is_bad(void *p)
{
if (!p)
return 1;
if (IS_ERR(p) && (PTR_ERR(p) != -ENODEV))
return 1;
return 0;
}
struct dentry **tpm_bios_log_setup(char *name)
{
struct dentry **ret = NULL, *tpm_dir, *bin_file, *ascii_file;
tpm_dir = securityfs_create_dir(name, NULL);
if (is_bad(tpm_dir))
goto out;
bin_file =
securityfs_create_file("binary_bios_measurements",
S_IRUSR | S_IRGRP, tpm_dir, NULL,
&tpm_binary_bios_measurements_ops);
if (is_bad(bin_file))
goto out_tpm;
ascii_file =
securityfs_create_file("ascii_bios_measurements",
S_IRUSR | S_IRGRP, tpm_dir, NULL,
&tpm_ascii_bios_measurements_ops);
if (is_bad(ascii_file))
goto out_bin;
ret = kmalloc(3 * sizeof(struct dentry *), GFP_KERNEL);
if (!ret)
goto out_ascii;
ret[0] = ascii_file;
ret[1] = bin_file;
ret[2] = tpm_dir;
return ret;
out_ascii:
securityfs_remove(ascii_file);
out_bin:
securityfs_remove(bin_file);
out_tpm:
securityfs_remove(tpm_dir);
out:
return NULL;
}
EXPORT_SYMBOL_GPL(tpm_bios_log_setup);
void tpm_bios_log_teardown(struct dentry **lst)
{
int i;
for (i = 0; i < 3; i++)
securityfs_remove(lst[i]);
}
EXPORT_SYMBOL_GPL(tpm_bios_log_teardown);
MODULE_LICENSE("GPL");