1 files changed, 469 insertions, 0 deletions
diff --git a/drivers/char/tpm/tpm1_eventlog.c b/drivers/char/tpm/tpm1_eventlog.c
new file mode 100644
index 000000000000..9a8605e500b5
--- /dev/null
+++ b/drivers/char/tpm/tpm1_eventlog.c
@@ -0,0 +1,469 @@
+/*
+ * Copyright (C) 2005, 2012 IBM Corporation
+ *
+ * Authors:
+ *	Kent Yoder <key@linux.vnet.ibm.com>
+ *	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 created by a system's firmware / BIOS
+ *
+ * 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 <linux/slab.h>
+
+#include "tpm.h"
+#include "tpm_eventlog.h"
+
+
+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"
+};
+
+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_chip *chip = m->private;
+	struct tpm_bios_log *log = &chip->log;
+	void *addr = log->bios_event_log;
+	void *limit = log->bios_event_log_end;
+	struct tcpa_event *event;
+	u32 converted_event_size;
+	u32 converted_event_type;
+
+
+	/* read over *pos measurements */
+	for (i = 0; i < *pos; i++) {
+		event = addr;
+
+		converted_event_size =
+		    do_endian_conversion(event->event_size);
+		converted_event_type =
+		    do_endian_conversion(event->event_type);
+
+		if ((addr + sizeof(struct tcpa_event)) < limit) {
+			if ((converted_event_type == 0) &&
+			    (converted_event_size == 0))
+				return NULL;
+			addr += (sizeof(struct tcpa_event) +
+				 converted_event_size);
+		}
+	}
+
+	/* now check if current entry is valid */
+	if ((addr + sizeof(struct tcpa_event)) >= limit)
+		return NULL;
+
+	event = addr;
+
+	converted_event_size = do_endian_conversion(event->event_size);
+	converted_event_type = do_endian_conversion(event->event_type);
+
+	if (((converted_event_type == 0) && (converted_event_size == 0))
+	    || ((addr + sizeof(struct tcpa_event) + converted_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_chip *chip = m->private;
+	struct tpm_bios_log *log = &chip->log;
+	void *limit = log->bios_event_log_end;
+	u32 converted_event_size;
+	u32 converted_event_type;
+
+	converted_event_size = do_endian_conversion(event->event_size);
+
+	v += sizeof(struct tcpa_event) + converted_event_size;
+
+	/* now check if current entry is valid */
+	if ((v + sizeof(struct tcpa_event)) >= limit)
+		return NULL;
+
+	event = v;
+
+	converted_event_size = do_endian_conversion(event->event_size);
+	converted_event_type = do_endian_conversion(event->event_type);
+
+	if (((converted_event_type == 0) && (converted_event_size == 0)) ||
+	    ((v + sizeof(struct tcpa_event) + converted_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 (do_endian_conversion(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[do_endian_conversion
+						(event->event_type)];
+		n_len = strlen(name);
+		break;
+	case SEPARATOR:
+	case ACTION:
+		if (MAX_TEXT_EVENT >
+		    do_endian_conversion(event->event_size)) {
+			name = event_entry;
+			n_len = do_endian_conversion(event->event_size);
+		}
+		break;
+	case EVENT_TAG:
+		pc_event = (struct tcpa_pc_event *)event_entry;
+
+		/* ToDo Row data -> Base64 */
+
+		switch (do_endian_conversion(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[do_endian_conversion
+							(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[do_endian_conversion
+							(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;
+	struct tcpa_event temp_event;
+	char *temp_ptr;
+	int i;
+
+	memcpy(&temp_event, event, sizeof(struct tcpa_event));
+
+	/* convert raw integers for endianness */
+	temp_event.pcr_index = do_endian_conversion(event->pcr_index);
+	temp_event.event_type = do_endian_conversion(event->event_type);
+	temp_event.event_size = do_endian_conversion(event->event_size);
+
+	temp_ptr = (char *) &temp_event;
+
+	for (i = 0; i < (sizeof(struct tcpa_event) - 1) ; i++)
+		seq_putc(m, temp_ptr[i]);
+
+	temp_ptr = (char *) v;
+
+	for (i = (sizeof(struct tcpa_event) - 1);
+	     i < (sizeof(struct tcpa_event) + temp_event.event_size); i++)
+		seq_putc(m, temp_ptr[i]);
+
+	return 0;
+
+}
+
+static int tpm_bios_measurements_release(struct inode *inode,
+					 struct file *file)
+{
+	struct seq_file *seq = (struct seq_file *)file->private_data;
+	struct tpm_chip *chip = (struct tpm_chip *)seq->private;
+
+	put_device(&chip->dev);
+
+	return seq_release(inode, file);
+}
+
+static int tpm_ascii_bios_measurements_show(struct seq_file *m, void *v)
+{
+	int len = 0;
+	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;
+	}
+
+	/* 1st: PCR */
+	seq_printf(m, "%2d ", do_endian_conversion(event->pcr_index));
+
+	/* 2nd: SHA1 */
+	seq_printf(m, "%20phN", event->pcr_value);
+
+	/* 3rd: event type identifier */
+	seq_printf(m, " %02x", do_endian_conversion(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_measurements_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_measurements_seqops = {
+	.start = tpm_bios_measurements_start,
+	.next = tpm_bios_measurements_next,
+	.stop = tpm_bios_measurements_stop,
+	.show = tpm_binary_bios_measurements_show,
+};
+
+static int tpm_bios_measurements_open(struct inode *inode,
+					    struct file *file)
+{
+	int err;
+	struct seq_file *seq;
+	struct tpm_chip_seqops *chip_seqops;
+	const struct seq_operations *seqops;
+	struct tpm_chip *chip;
+
+	inode_lock(inode);
+	if (!inode->i_private) {
+		inode_unlock(inode);
+		return -ENODEV;
+	}
+	chip_seqops = (struct tpm_chip_seqops *)inode->i_private;
+	seqops = chip_seqops->seqops;
+	chip = chip_seqops->chip;
+	get_device(&chip->dev);
+	inode_unlock(inode);
+
+	/* now register seq file */
+	err = seq_open(file, seqops);
+	if (!err) {
+		seq = file->private_data;
+		seq->private = chip;
+	}
+
+	return err;
+}
+
+static const struct file_operations tpm_bios_measurements_ops = {
+	.owner = THIS_MODULE,
+	.open = tpm_bios_measurements_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = tpm_bios_measurements_release,
+};
+
+static int tpm_read_log(struct tpm_chip *chip)
+{
+	int rc;
+
+	if (chip->log.bios_event_log != NULL) {
+		dev_dbg(&chip->dev,
+			"%s: ERROR - event log already initialized\n",
+			__func__);
+		return -EFAULT;
+	}
+
+	rc = tpm_read_log_acpi(chip);
+	if (rc != -ENODEV)
+		return rc;
+
+	return tpm_read_log_of(chip);
+}
+
+/*
+ * tpm_bios_log_setup() - Read the event log from the firmware
+ * @chip: TPM chip to use.
+ *
+ * If an event log is found then the securityfs files are setup to
+ * export it to userspace, otherwise nothing is done.
+ *
+ * Returns -ENODEV if the firmware has no event log or securityfs is not
+ * supported.
+ */
+int tpm_bios_log_setup(struct tpm_chip *chip)
+{
+	const char *name = dev_name(&chip->dev);
+	unsigned int cnt;
+	int rc = 0;
+
+	rc = tpm_read_log(chip);
+	if (rc)
+		return rc;
+
+	cnt = 0;
+	chip->bios_dir[cnt] = securityfs_create_dir(name, NULL);
+	/* NOTE: securityfs_create_dir can return ENODEV if securityfs is
+	 * compiled out. The caller should ignore the ENODEV return code.
+	 */
+	if (IS_ERR(chip->bios_dir[cnt]))
+		goto err;
+	cnt++;
+
+	chip->bin_log_seqops.chip = chip;
+	if (chip->flags & TPM_CHIP_FLAG_TPM2)
+		chip->bin_log_seqops.seqops =
+			&tpm2_binary_b_measurements_seqops;
+	else
+		chip->bin_log_seqops.seqops =
+			&tpm_binary_b_measurements_seqops;
+
+
+	chip->bios_dir[cnt] =
+	    securityfs_create_file("binary_bios_measurements",
+				   0440, chip->bios_dir[0],
+				   (void *)&chip->bin_log_seqops,
+				   &tpm_bios_measurements_ops);
+	if (IS_ERR(chip->bios_dir[cnt]))
+		goto err;
+	cnt++;
+
+	if (!(chip->flags & TPM_CHIP_FLAG_TPM2)) {
+
+		chip->ascii_log_seqops.chip = chip;
+		chip->ascii_log_seqops.seqops =
+			&tpm_ascii_b_measurements_seqops;
+
+		chip->bios_dir[cnt] =
+			securityfs_create_file("ascii_bios_measurements",
+					       0440, chip->bios_dir[0],
+					       (void *)&chip->ascii_log_seqops,
+					       &tpm_bios_measurements_ops);
+		if (IS_ERR(chip->bios_dir[cnt]))
+			goto err;
+		cnt++;
+	}
+
+	return 0;
+
+err:
+	rc = PTR_ERR(chip->bios_dir[cnt]);
+	chip->bios_dir[cnt] = NULL;
+	tpm_bios_log_teardown(chip);
+	return rc;
+}
+
+void tpm_bios_log_teardown(struct tpm_chip *chip)
+{
+	int i;
+	struct inode *inode;
+
+	/* securityfs_remove currently doesn't take care of handling sync
+	 * between removal and opening of pseudo files. To handle this, a
+	 * workaround is added by making i_private = NULL here during removal
+	 * and to check it during open(), both within inode_lock()/unlock().
+	 * This design ensures that open() either safely gets kref or fails.
+	 */
+	for (i = (TPM_NUM_EVENT_LOG_FILES - 1); i >= 0; i--) {
+		if (chip->bios_dir[i]) {
+			inode = d_inode(chip->bios_dir[i]);
+			inode_lock(inode);
+			inode->i_private = NULL;
+			inode_unlock(inode);
+			securityfs_remove(chip->bios_dir[i]);
+		}
+	}
+}