tpm: modularize event log collection
Break ACPI-specific pieces of the event log handling into their own file
and create tpm_eventlog.[ch] to store common event log handling code.
This will be required to integrate future event log sources on platforms
without ACPI tables.
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
diff --git a/drivers/char/tpm/tpm_eventlog.c b/drivers/char/tpm/tpm_eventlog.c
new file mode 100644
index 0000000..84ddc55
--- /dev/null
+++ b/drivers/char/tpm/tpm_eventlog.c
@@ -0,0 +1,419 @@
+/*
+ * 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>
+ *
+ * Maintained by: <tpmdd-devel@lists.sourceforge.net>
+ *
+ * Access to the eventlog 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_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,
+};
+
+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");