diff options
Diffstat (limited to 'drivers/char/tpm/tpm_eventlog.c')
-rw-r--r-- | drivers/char/tpm/tpm_eventlog.c | 419 |
1 files changed, 419 insertions, 0 deletions
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"); |