LXR linux/drivers/char/tpm/eventlog/tpm1.c

   1/*
   2 * Copyright (C) 2005, 2012 IBM Corporation
   3 *
   4 * Authors:
   5 *      Kent Yoder <key@linux.vnet.ibm.com>
   6 *      Seiji Munetoh <munetoh@jp.ibm.com>
   7 *      Stefan Berger <stefanb@us.ibm.com>
   8 *      Reiner Sailer <sailer@watson.ibm.com>
   9 *      Kylene Hall <kjhall@us.ibm.com>
  10 *      Nayna Jain <nayna@linux.vnet.ibm.com>
  11 *
  12 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
  13 *
  14 * Access to the event log created by a system's firmware / BIOS
  15 *
  16 * This program is free software; you can redistribute it and/or
  17 * modify it under the terms of the GNU General Public License
  18 * as published by the Free Software Foundation; either version
  19 * 2 of the License, or (at your option) any later version.
  20 *
  21 */
  22
  23#include <linux/seq_file.h>
  24#include <linux/efi.h>
  25#include <linux/fs.h>
  26#include <linux/security.h>
  27#include <linux/module.h>
  28#include <linux/slab.h>
  29#include <linux/tpm_eventlog.h>
  30
  31#include "../tpm.h"
  32#include "common.h"
  33
  34
  35static const char* tcpa_event_type_strings[] = {
  36        "PREBOOT",
  37        "POST CODE",
  38        "",
  39        "NO ACTION",
  40        "SEPARATOR",
  41        "ACTION",
  42        "EVENT TAG",
  43        "S-CRTM Contents",
  44        "S-CRTM Version",
  45        "CPU Microcode",
  46        "Platform Config Flags",
  47        "Table of Devices",
  48        "Compact Hash",
  49        "IPL",
  50        "IPL Partition Data",
  51        "Non-Host Code",
  52        "Non-Host Config",
  53        "Non-Host Info"
  54};
  55
  56static const char* tcpa_pc_event_id_strings[] = {
  57        "",
  58        "SMBIOS",
  59        "BIS Certificate",
  60        "POST BIOS ",
  61        "ESCD ",
  62        "CMOS",
  63        "NVRAM",
  64        "Option ROM",
  65        "Option ROM config",
  66        "",
  67        "Option ROM microcode ",
  68        "S-CRTM Version",
  69        "S-CRTM Contents ",
  70        "POST Contents ",
  71        "Table of Devices",
  72};
  73
  74/* returns pointer to start of pos. entry of tcg log */
  75static void *tpm1_bios_measurements_start(struct seq_file *m, loff_t *pos)
  76{
  77        loff_t i = 0;
  78        struct tpm_chip *chip = m->private;
  79        struct tpm_bios_log *log = &chip->log;
  80        void *addr = log->bios_event_log;
  81        void *limit = log->bios_event_log_end;
  82        struct tcpa_event *event;
  83        u32 converted_event_size;
  84        u32 converted_event_type;
  85
  86        /* read over *pos measurements */
  87        do {
  88                event = addr;
  89
  90                /* check if current entry is valid */
  91                if (addr + sizeof(struct tcpa_event) > limit)
  92                        return NULL;
  93
  94                converted_event_size =
  95                    do_endian_conversion(event->event_size);
  96                converted_event_type =
  97                    do_endian_conversion(event->event_type);
  98
  99                if (((converted_event_type == 0) && (converted_event_size == 0))
 100                    || ((addr + sizeof(struct tcpa_event) + converted_event_size)
 101                        > limit))
 102                        return NULL;
 103
 104                if (i++ == *pos)
 105                        break;
 106
 107                addr += (sizeof(struct tcpa_event) + converted_event_size);
 108        } while (1);
 109
 110        return addr;
 111}
 112
 113static void *tpm1_bios_measurements_next(struct seq_file *m, void *v,
 114                                        loff_t *pos)
 115{
 116        struct tcpa_event *event = v;
 117        struct tpm_chip *chip = m->private;
 118        struct tpm_bios_log *log = &chip->log;
 119        void *limit = log->bios_event_log_end;
 120        u32 converted_event_size;
 121        u32 converted_event_type;
 122
 123        converted_event_size = do_endian_conversion(event->event_size);
 124
 125        v += sizeof(struct tcpa_event) + converted_event_size;
 126
 127        /* now check if current entry is valid */
 128        if ((v + sizeof(struct tcpa_event)) > limit)
 129                return NULL;
 130
 131        event = v;
 132
 133        converted_event_size = do_endian_conversion(event->event_size);
 134        converted_event_type = do_endian_conversion(event->event_type);
 135
 136        if (((converted_event_type == 0) && (converted_event_size == 0)) ||
 137            ((v + sizeof(struct tcpa_event) + converted_event_size) > limit))
 138                return NULL;
 139
 140        (*pos)++;
 141        return v;
 142}
 143
 144static void tpm1_bios_measurements_stop(struct seq_file *m, void *v)
 145{
 146}
 147
 148static int get_event_name(char *dest, struct tcpa_event *event,
 149                        unsigned char * event_entry)
 150{
 151        const char *name = "";
 152        /* 41 so there is room for 40 data and 1 nul */
 153        char data[41] = "";
 154        int i, n_len = 0, d_len = 0;
 155        struct tcpa_pc_event *pc_event;
 156
 157        switch (do_endian_conversion(event->event_type)) {
 158        case PREBOOT:
 159        case POST_CODE:
 160        case UNUSED:
 161        case NO_ACTION:
 162        case SCRTM_CONTENTS:
 163        case SCRTM_VERSION:
 164        case CPU_MICROCODE:
 165        case PLATFORM_CONFIG_FLAGS:
 166        case TABLE_OF_DEVICES:
 167        case COMPACT_HASH:
 168        case IPL:
 169        case IPL_PARTITION_DATA:
 170        case NONHOST_CODE:
 171        case NONHOST_CONFIG:
 172        case NONHOST_INFO:
 173                name = tcpa_event_type_strings[do_endian_conversion
 174                                                (event->event_type)];
 175                n_len = strlen(name);
 176                break;
 177        case SEPARATOR:
 178        case ACTION:
 179                if (MAX_TEXT_EVENT >
 180                    do_endian_conversion(event->event_size)) {
 181                        name = event_entry;
 182                        n_len = do_endian_conversion(event->event_size);
 183                }
 184                break;
 185        case EVENT_TAG:
 186                pc_event = (struct tcpa_pc_event *)event_entry;
 187
 188                /* ToDo Row data -> Base64 */
 189
 190                switch (do_endian_conversion(pc_event->event_id)) {
 191                case SMBIOS:
 192                case BIS_CERT:
 193                case CMOS:
 194                case NVRAM:
 195                case OPTION_ROM_EXEC:
 196                case OPTION_ROM_CONFIG:
 197                case S_CRTM_VERSION:
 198                        name = tcpa_pc_event_id_strings[do_endian_conversion
 199                                                        (pc_event->event_id)];
 200                        n_len = strlen(name);
 201                        break;
 202                /* hash data */
 203                case POST_BIOS_ROM:
 204                case ESCD:
 205                case OPTION_ROM_MICROCODE:
 206                case S_CRTM_CONTENTS:
 207                case POST_CONTENTS:
 208                        name = tcpa_pc_event_id_strings[do_endian_conversion
 209                                                        (pc_event->event_id)];
 210                        n_len = strlen(name);
 211                        for (i = 0; i < 20; i++)
 212                                d_len += sprintf(&data[2*i], "%02x",
 213                                                pc_event->event_data[i]);
 214                        break;
 215                default:
 216                        break;
 217                }
 218        default:
 219                break;
 220        }
 221
 222        return snprintf(dest, MAX_TEXT_EVENT, "[%.*s%.*s]",
 223                        n_len, name, d_len, data);
 224
 225}
 226
 227static int tpm1_binary_bios_measurements_show(struct seq_file *m, void *v)
 228{
 229        struct tcpa_event *event = v;
 230        struct tcpa_event temp_event;
 231        char *temp_ptr;
 232        int i;
 233
 234        memcpy(&temp_event, event, sizeof(struct tcpa_event));
 235
 236        /* convert raw integers for endianness */
 237        temp_event.pcr_index = do_endian_conversion(event->pcr_index);
 238        temp_event.event_type = do_endian_conversion(event->event_type);
 239        temp_event.event_size = do_endian_conversion(event->event_size);
 240
 241        temp_ptr = (char *) &temp_event;
 242
 243        for (i = 0; i < (sizeof(struct tcpa_event) - 1) ; i++)
 244                seq_putc(m, temp_ptr[i]);
 245
 246        temp_ptr = (char *) v;
 247
 248        for (i = (sizeof(struct tcpa_event) - 1);
 249             i < (sizeof(struct tcpa_event) + temp_event.event_size); i++)
 250                seq_putc(m, temp_ptr[i]);
 251
 252        return 0;
 253
 254}
 255
 256static int tpm1_ascii_bios_measurements_show(struct seq_file *m, void *v)
 257{
 258        int len = 0;
 259        char *eventname;
 260        struct tcpa_event *event = v;
 261        unsigned char *event_entry =
 262            (unsigned char *)(v + sizeof(struct tcpa_event));
 263
 264        eventname = kmalloc(MAX_TEXT_EVENT, GFP_KERNEL);
 265        if (!eventname) {
 266                printk(KERN_ERR "%s: ERROR - No Memory for event name\n ",
 267                       __func__);
 268                return -EFAULT;
 269        }
 270
 271        /* 1st: PCR */
 272        seq_printf(m, "%2d ", do_endian_conversion(event->pcr_index));
 273
 274        /* 2nd: SHA1 */
 275        seq_printf(m, "%20phN", event->pcr_value);
 276
 277        /* 3rd: event type identifier */
 278        seq_printf(m, " %02x", do_endian_conversion(event->event_type));
 279
 280        len += get_event_name(eventname, event, event_entry);
 281
 282        /* 4th: eventname <= max + \'0' delimiter */
 283        seq_printf(m, " %s\n", eventname);
 284
 285        kfree(eventname);
 286        return 0;
 287}
 288
 289const struct seq_operations tpm1_ascii_b_measurements_seqops = {
 290        .start = tpm1_bios_measurements_start,
 291        .next = tpm1_bios_measurements_next,
 292        .stop = tpm1_bios_measurements_stop,
 293        .show = tpm1_ascii_bios_measurements_show,
 294};
 295
 296const struct seq_operations tpm1_binary_b_measurements_seqops = {
 297        .start = tpm1_bios_measurements_start,
 298        .next = tpm1_bios_measurements_next,
 299        .stop = tpm1_bios_measurements_stop,
 300        .show = tpm1_binary_bios_measurements_show,
 301};
 302