blob: 61cbb910bd474fea9c15a2070bb37988b3367e57 [file] [log] [blame]
/* Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*
* High-level firmware wrapper API - entry points for kernel selection
*/
#include "gbb_header.h"
#include "load_kernel_fw.h"
#include "rollback_index.h"
#include "utility.h"
#include "vboot_api.h"
#include "vboot_common.h"
#include "vboot_nvstorage.h"
/* Global variables */
static uint32_t disp_current_screen = VB_SCREEN_BLANK;
static uint32_t disp_width = 0, disp_height = 0;
static VbNvContext vnc;
#ifdef CHROMEOS_ENVIRONMENT
/* Global variable accessors for unit tests */
VbNvContext* VbApiKernelGetVnc(void) {
return &vnc;
}
#endif
/* Set recovery request */
static void VbSetRecoveryRequest(uint32_t recovery_request) {
VBDEBUG(("VbSetRecoveryRequest(%d)\n", (int)recovery_request));
VbNvSet(&vnc, VBNV_RECOVERY_REQUEST, recovery_request);
}
/* Get the number of localizations in the GBB bitmap data. */
static VbError_t VbGetLocalizationCount(VbCommonParams* cparams,
uint32_t* count) {
GoogleBinaryBlockHeader* gbb = (GoogleBinaryBlockHeader*)cparams->gbb_data;
BmpBlockHeader* hdr;
/* Default to 0 on error */
*count = 0;
/* Make sure the bitmap data is inside the GBB and is non-zero in size */
if (0 == gbb->bmpfv_size ||
gbb->bmpfv_offset > cparams->gbb_size ||
gbb->bmpfv_offset + gbb->bmpfv_size > cparams->gbb_size) {
return VBERROR_INVALID_GBB;
}
/* Sanity-check the bitmap block header */
hdr = (BmpBlockHeader *)(((uint8_t*)gbb) + gbb->bmpfv_offset);
if ((0 != Memcmp(hdr->signature, BMPBLOCK_SIGNATURE,
BMPBLOCK_SIGNATURE_SIZE)) ||
(hdr->major_version > BMPBLOCK_MAJOR_VERSION) ||
((hdr->major_version == BMPBLOCK_MAJOR_VERSION) &&
(hdr->minor_version > BMPBLOCK_MINOR_VERSION))) {
return VBERROR_INVALID_BMPFV;
}
*count = hdr->number_of_localizations;
return VBERROR_SUCCESS;
}
/* Display a screen from the GBB. */
static VbError_t VbDisplayScreenFromGBB(VbCommonParams* cparams,
uint32_t screen) {
GoogleBinaryBlockHeader* gbb = (GoogleBinaryBlockHeader*)cparams->gbb_data;
uint8_t* bmpfv = NULL;
BmpBlockHeader* hdr;
ScreenLayout* layout;
ImageInfo* image_info;
uint32_t screen_index;
uint32_t localization = 0;
VbError_t retval = VBERROR_UNKNOWN; /* Assume error until proven
* successful */
uint32_t offset;
uint32_t i;
/* Make sure the bitmap data is inside the GBB and is non-zero in size */
if (0 == gbb->bmpfv_size ||
gbb->bmpfv_offset > cparams->gbb_size ||
gbb->bmpfv_offset + gbb->bmpfv_size > cparams->gbb_size) {
VBDEBUG(("VbDisplayScreenFromGBB(): invalid bmpfv offset/size\n"));
return VBERROR_INVALID_GBB;
}
/* Copy bitmap data from GBB into RAM for speed */
bmpfv = (uint8_t*)VbExMalloc(gbb->bmpfv_size);
Memcpy(bmpfv, ((uint8_t*)gbb) + gbb->bmpfv_offset, gbb->bmpfv_size);
/* Sanity-check the bitmap block header */
hdr = (BmpBlockHeader *)bmpfv;
if ((0 != Memcmp(hdr->signature, BMPBLOCK_SIGNATURE,
BMPBLOCK_SIGNATURE_SIZE)) ||
(hdr->major_version > BMPBLOCK_MAJOR_VERSION) ||
((hdr->major_version == BMPBLOCK_MAJOR_VERSION) &&
(hdr->minor_version > BMPBLOCK_MINOR_VERSION))) {
VBDEBUG(("VbDisplayScreenFromGBB(): invalid/too new bitmap header\n"));
retval = VBERROR_INVALID_BMPFV;
goto VbDisplayScreenFromGBB_exit;
}
/* Translate screen ID into index. Note that not all screens are in the
* GBB. */
/* TODO: ensure screen IDs match indices? Having this translation
* here is awful. */
switch (screen) {
case VB_SCREEN_DEVELOPER_WARNING:
screen_index = 0;
break;
case VB_SCREEN_RECOVERY_REMOVE:
screen_index = 1;
break;
case VB_SCREEN_RECOVERY_NO_GOOD:
screen_index = 2;
break;
case VB_SCREEN_RECOVERY_INSERT:
screen_index = 3;
break;
case VB_SCREEN_BLANK:
case VB_SCREEN_DEVELOPER_EGG:
default:
/* Screens which aren't in the GBB */
VBDEBUG(("VbDisplayScreenFromGBB(): screen %d not in the GBB\n",
(int)screen));
retval = VBERROR_INVALID_SCREEN_INDEX;
goto VbDisplayScreenFromGBB_exit;
}
if (screen_index >= hdr->number_of_screenlayouts) {
VBDEBUG(("VbDisplayScreenFromGBB(): screen %d index %d not in the GBB\n",
(int)screen, (int)screen_index));
retval = VBERROR_INVALID_SCREEN_INDEX;
goto VbDisplayScreenFromGBB_exit;
}
/* Clip localization to the number of localizations present in the GBB */
VbNvGet(&vnc, VBNV_LOCALIZATION_INDEX, &localization);
if (localization >= hdr->number_of_localizations) {
localization = 0;
VbNvSet(&vnc, VBNV_LOCALIZATION_INDEX, localization);
}
/* Calculate offset of screen layout = start of screen stuff +
* correct locale + correct screen. */
offset = sizeof(BmpBlockHeader) +
localization * hdr->number_of_screenlayouts * sizeof(ScreenLayout) +
screen_index * sizeof(ScreenLayout);
VBDEBUG(("VbDisplayScreenFromGBB(): scr_%d_%d at offset 0x%x\n",
localization, screen_index, offset));
layout = (ScreenLayout*)(bmpfv + offset);
/* Display all bitmaps for the image */
for (i = 0; i < MAX_IMAGE_IN_LAYOUT; i++) {
if (layout->images[i].image_info_offset) {
offset = layout->images[i].image_info_offset;
image_info = (ImageInfo*)(bmpfv + offset);
VBDEBUG(("VbDisplayScreenFromGBB: image %d: %dx%d+%d+%d %d/%d"
"tag %d at 0x%x\n",
i, image_info->width, image_info->height,
layout->images[i].x, layout->images[i].y,
image_info->compressed_size, image_info->original_size,
image_info->tag, offset));
retval = VbExDisplayImage(layout->images[i].x, layout->images[i].y,
image_info, bmpfv + offset + sizeof(ImageInfo));
if (VBERROR_SUCCESS != retval)
goto VbDisplayScreenFromGBB_exit;
}
}
/* Successful if all bitmaps displayed */
retval = VBERROR_SUCCESS;
VbDisplayScreenFromGBB_exit:
/* Free the bitmap data copy */
VbExFree(bmpfv);
return retval;
}
/* Display a screen, initializing the display if necessary. If force!=0,
* redisplays the screen even if it's the same as the current screen. */
static VbError_t VbDisplayScreen(VbCommonParams* cparams, uint32_t screen,
int force) {
VbError_t retval;
VBDEBUG(("VbDisplayScreen(%d, %d)\n", (int)screen, force));
/* Initialize display if necessary */
if (!disp_width) {
retval = VbExDisplayInit(&disp_width, &disp_height);
if (VBERROR_SUCCESS != retval)
return retval;
}
/* If the requested screen is the same as the current one, we're done. */
if (disp_current_screen == screen && 0 == force)
return VBERROR_SUCCESS;
/* If the screen is blank, turn off the backlight; else turn it on. */
VbExDisplayBacklight(VB_SCREEN_BLANK == screen ? 0 : 1);
/* Request the screen */
disp_current_screen = screen;
/* Look in the GBB first */
if (VBERROR_SUCCESS == VbDisplayScreenFromGBB(cparams, screen))
return VBERROR_SUCCESS;
/* If the screen wasn't in the GBB bitmaps, fall back to a default screen. */
return VbExDisplayScreen(screen);
}
#define DEBUG_INFO_SIZE 512
/* Display debug info to the screen */
static VbError_t VbDisplayDebugInfo(VbCommonParams* cparams) {
VbSharedDataHeader* shared = (VbSharedDataHeader*)cparams->shared_data_blob;
GoogleBinaryBlockHeader* gbb = (GoogleBinaryBlockHeader*)cparams->gbb_data;
char buf[DEBUG_INFO_SIZE] = "";
uint32_t used = 0;
uint32_t i;
/* Redisplay the current screen, to overwrite any previous debug output */
VbDisplayScreen(cparams, disp_current_screen, 1);
/* Add hardware ID */
used += Strncat(buf + used, "HWID: ", DEBUG_INFO_SIZE - used);
if (0 == gbb->hwid_size ||
gbb->hwid_offset > cparams->gbb_size ||
gbb->hwid_offset + gbb->hwid_size > cparams->gbb_size) {
VBDEBUG(("VbCheckDisplayKey(): invalid hwid offset/size\n"));
used += Strncat(buf + used, "(INVALID)", DEBUG_INFO_SIZE - used);
} else {
used += Strncat(buf + used, (char*)((uint8_t*)gbb + gbb->hwid_offset),
DEBUG_INFO_SIZE - used);
}
/* Add recovery reason */
used += Strncat(buf + used, "\nrecovery_reason: 0x", DEBUG_INFO_SIZE - used);
used += Uint64ToString(buf + used, DEBUG_INFO_SIZE - used,
shared->recovery_reason, 16, 2);
/* Add VbSharedData flags */
used += Strncat(buf + used, "\nVbSD.flags: 0x", DEBUG_INFO_SIZE - used);
used += Uint64ToString(buf + used, DEBUG_INFO_SIZE - used,
shared->flags, 16, 8);
/* Add raw contents of VbNvStorage */
used += Strncat(buf + used, "\nVbNv.raw:", DEBUG_INFO_SIZE - used);
for (i = 0; i < VBNV_BLOCK_SIZE; i++) {
used += Strncat(buf + used, " ", DEBUG_INFO_SIZE - used);
used += Uint64ToString(buf + used, DEBUG_INFO_SIZE - used,
vnc.raw[i], 16, 2);
}
/* Add dev_boot_usb flag */
VbNvGet(&vnc, VBNV_DEV_BOOT_USB, &i);
used += Strncat(buf + used, "\ndev_boot_usb: ", DEBUG_INFO_SIZE - used);
used += Uint64ToString(buf + used, DEBUG_INFO_SIZE - used, i, 10, 0);
/* Add TPM versions */
used += Strncat(buf + used, "\nTPM: fwver=0x", DEBUG_INFO_SIZE - used);
used += Uint64ToString(buf + used, DEBUG_INFO_SIZE - used,
shared->fw_version_tpm, 16, 8);
used += Strncat(buf + used, " kernver=0x", DEBUG_INFO_SIZE - used);
used += Uint64ToString(buf + used, DEBUG_INFO_SIZE - used,
shared->kernel_version_tpm, 16, 8);
/* Add GBB flags */
used += Strncat(buf + used, "\ngbb.flags: 0x", DEBUG_INFO_SIZE - used);
if (gbb->major_version == GBB_MAJOR_VER && gbb->minor_version >= 1) {
used += Uint64ToString(buf + used, DEBUG_INFO_SIZE - used,
gbb->flags, 16, 8);
} else {
used += Strncat(buf + used, "0 (default)", DEBUG_INFO_SIZE - used);
}
/* Make sure we finish with a newline */
used += Strncat(buf + used, "\n", DEBUG_INFO_SIZE - used);
/* TODO: add more interesting data:
* - SHA1 of kernel subkey (assuming we always set it in VbSelectFirmware,
* even in recovery mode, where we just copy it from the root key)
* - Information on current disks */
buf[DEBUG_INFO_SIZE - 1] = '\0';
return VbExDisplayDebugInfo(buf);
}
static VbError_t VbCheckDisplayKey(VbCommonParams* cparams, uint32_t key) {
if ('\t' == key) {
/* Tab = display debug info */
return VbDisplayDebugInfo(cparams);
} else if (VB_KEY_LEFT == key || VB_KEY_RIGHT == key) {
/* Arrow keys = change localization */
uint32_t loc = 0;
uint32_t count = 0;
VbNvGet(&vnc, VBNV_LOCALIZATION_INDEX, &loc);
if (VBERROR_SUCCESS != VbGetLocalizationCount(cparams, &count))
loc = 0; /* No localization count (bad GBB?), so set to 0 (default) */
else if (VB_KEY_RIGHT == key)
loc = (loc < count - 1 ? loc + 1 : 0);
else
loc = (loc > 0 ? loc - 1 : count - 1);
VBDEBUG(("VbCheckDisplayKey() - change localization to %d\n", (int)loc));
VbNvSet(&vnc, VBNV_LOCALIZATION_INDEX, loc);
/* Force redraw of current screen */
return VbDisplayScreen(cparams, disp_current_screen, 1);
}
return VBERROR_SUCCESS;
}
/* Attempt loading a kernel from the specified type(s) of disks. If
* successful, sets p->disk_handle to the disk for the kernel and returns
* VBERROR_SUCCESS.
*
* Returns VBERROR_NO_DISK_FOUND if no disks of the specified type were found.
*
* May return other VBERROR_ codes for other failures. */
uint32_t VbTryLoadKernel(VbCommonParams* cparams, LoadKernelParams* p,
uint32_t get_info_flags) {
VbError_t retval = VBERROR_UNKNOWN;
VbDiskInfo* disk_info = NULL;
uint32_t disk_count = 0;
uint32_t i;
VBDEBUG(("VbTryLoadKernel() start, get_info_flags=0x%x\n",
(unsigned)get_info_flags));
p->disk_handle = NULL;
/* Find disks */
if (VBERROR_SUCCESS != VbExDiskGetInfo(&disk_info, &disk_count,
get_info_flags))
disk_count = 0;
VBDEBUG(("VbTryLoadKernel() found %d disks\n", (int)disk_count));
if (0 == disk_count) {
VbSetRecoveryRequest(VBNV_RECOVERY_RW_NO_DISK);
return VBERROR_NO_DISK_FOUND;
}
/* Loop over disks */
for (i = 0; i < disk_count; i++) {
VBDEBUG(("VbTryLoadKernel() trying disk %d\n", (int)i));
p->disk_handle = disk_info[i].handle;
p->bytes_per_lba = disk_info[i].bytes_per_lba;
p->ending_lba = disk_info[i].lba_count - 1;
retval = LoadKernel(p);
VBDEBUG(("VbTryLoadKernel() LoadKernel() returned %d\n", retval));
/* Stop now if we found a kernel */
/* TODO: If recovery requested, should track the farthest we get, instead
* of just returning the value from the last disk attempted. */
if (VBERROR_SUCCESS == retval)
break;
}
/* If we didn't succeed, don't return a disk handle */
if (VBERROR_SUCCESS != retval)
p->disk_handle = NULL;
VbExDiskFreeInfo(disk_info, p->disk_handle);
/* Pass through return code. Recovery reason (if any) has already been set
* by LoadKernel(). */
return retval;
}
/* Handle a normal boot. */
VbError_t VbBootNormal(VbCommonParams* cparams, LoadKernelParams* p) {
/* Force dev_boot_usb flag disabled. This ensures the flag will be
* initially disabled if the user later transitions back into
* developer mode. */
VbNvSet(&vnc, VBNV_DEV_BOOT_USB, 0);
/* Boot from fixed disk only */
return VbTryLoadKernel(cparams, p, VB_DISK_FLAG_FIXED);
}
/* Developer mode delays. All must be multiples of DEV_DELAY_INCREMENT */
#define DEV_DELAY_INCREMENT 250 /* Delay each loop, in msec */
#define DEV_DELAY_BEEP1 20000 /* Beep for first time at this time */
#define DEV_DELAY_BEEP2 21000 /* Beep for second time at this time */
#define DEV_DELAY_TIMEOUT 30000 /* Give up at this time */
#define DEV_DELAY_TIMEOUT_SHORT 2000 /* Give up at this time (short delay) */
/* Handle a developer-mode boot */
VbError_t VbBootDeveloper(VbCommonParams* cparams, LoadKernelParams* p) {
GoogleBinaryBlockHeader* gbb = (GoogleBinaryBlockHeader*)cparams->gbb_data;
uint32_t delay_timeout = DEV_DELAY_TIMEOUT;
uint32_t delay_time = 0;
uint32_t allow_usb = 0;
/* Check if USB booting is allowed */
VbNvGet(&vnc, VBNV_DEV_BOOT_USB, &allow_usb);
/* Use a short developer screen delay if indicated by GBB flags */
if (gbb->major_version == GBB_MAJOR_VER && gbb->minor_version >= 1
&& (gbb->flags & GBB_FLAG_DEV_SCREEN_SHORT_DELAY)) {
VBDEBUG(("VbBootDeveloper() - using short developer screen delay\n"));
delay_timeout = DEV_DELAY_TIMEOUT_SHORT;
}
/* Show the dev mode warning screen */
VbDisplayScreen(cparams, VB_SCREEN_DEVELOPER_WARNING, 0);
/* Loop for dev mode warning delay */
for (delay_time = 0; delay_time < delay_timeout;
delay_time += DEV_DELAY_INCREMENT) {
uint32_t key;
if (VbExIsShutdownRequested())
return VBERROR_SHUTDOWN_REQUESTED;
if (DEV_DELAY_BEEP1 == delay_time || DEV_DELAY_BEEP2 == delay_time)
VbExBeep(DEV_DELAY_INCREMENT, 400);
else
VbExSleepMs(DEV_DELAY_INCREMENT);
/* Handle keypress */
key = VbExKeyboardRead();
switch (key) {
case '\r':
case ' ':
case 0x1B:
/* Enter, space, or ESC = reboot to recovery */
VBDEBUG(("VbBootDeveloper() - user pressed ENTER/SPACE/ESC"));
VbSetRecoveryRequest(VBNV_RECOVERY_RW_DEV_SCREEN);
return 1;
case 0x04:
/* Ctrl+D = dismiss warning; advance to timeout */
VBDEBUG(("VbBootDeveloper() - user pressed Ctrl+D; skip delay\n"));
delay_time = DEV_DELAY_TIMEOUT;
break;
case 0x15:
/* Ctrl+U = try USB boot, or beep if failure */
VBDEBUG(("VbBootDeveloper() - user pressed Ctrl+U; try USB\n"));
if (!allow_usb) {
VBDEBUG(("VbBootDeveloper() - USB booting is disabled\n"));
VbExBeep(DEV_DELAY_INCREMENT / 2, 400);
VbExSleepMs(DEV_DELAY_INCREMENT / 2);
VbExBeep(DEV_DELAY_INCREMENT / 2, 400);
} else if (VBERROR_SUCCESS ==
VbTryLoadKernel(cparams, p, VB_DISK_FLAG_REMOVABLE)) {
VBDEBUG(("VbBootDeveloper() - booting USB\n"));
return VBERROR_SUCCESS;
} else {
VBDEBUG(("VbBootDeveloper() - no kernel found on USB\n"));
VbExBeep(DEV_DELAY_INCREMENT, 400);
/* Clear recovery requests from failed kernel loading, so
* that powering off at this point doesn't put us into
* recovery mode. */
VbSetRecoveryRequest(VBNV_RECOVERY_NOT_REQUESTED);
}
break;
default:
VbCheckDisplayKey(cparams, key);
break;
/* TODO: xyzzy easter egg check */
}
}
/* Timeout or Ctrl+D; attempt loading from fixed disk */
VBDEBUG(("VbBootDeveloper() - trying fixed disk\n"));
return VbTryLoadKernel(cparams, p, VB_DISK_FLAG_FIXED);
}
/* Delay between disk checks in recovery mode */
#define REC_DELAY_INCREMENT 250
/* Handle a recovery-mode boot */
VbError_t VbBootRecovery(VbCommonParams* cparams, LoadKernelParams* p) {
VbSharedDataHeader* shared = (VbSharedDataHeader*)cparams->shared_data_blob;
uint32_t retval;
int i;
VBDEBUG(("VbBootRecovery() start\n"));
/* If dev mode switch is off, require removal of all external media. */
if (!(shared->flags & VBSD_BOOT_DEV_SWITCH_ON)) {
VbDiskInfo* disk_info = NULL;
uint32_t disk_count = 0;
VBDEBUG(("VbBootRecovery() forcing device removal\n"));
while (1) {
if (VBERROR_SUCCESS != VbExDiskGetInfo(&disk_info, &disk_count,
VB_DISK_FLAG_REMOVABLE))
disk_count = 0;
VbExDiskFreeInfo(disk_info, NULL);
if (0 == disk_count) {
VbDisplayScreen(cparams, VB_SCREEN_BLANK, 0);
break;
}
VBDEBUG(("VbBootRecovery() waiting for %d disks to be removed\n",
(int)disk_count));
VbDisplayScreen(cparams, VB_SCREEN_RECOVERY_REMOVE, 0);
/* Scan keyboard more frequently than media, since x86 platforms
* don't like to scan USB too rapidly. */
for (i = 0; i < 4; i++) {
VbCheckDisplayKey(cparams, VbExKeyboardRead());
if (VbExIsShutdownRequested())
return VBERROR_SHUTDOWN_REQUESTED;
VbExSleepMs(REC_DELAY_INCREMENT);
}
}
}
/* Loop and wait for a recovery image */
while (1) {
VBDEBUG(("VbBootRecovery() attempting to load kernel\n"));
retval = VbTryLoadKernel(cparams, p, VB_DISK_FLAG_REMOVABLE);
/* Clear recovery requests from failed kernel loading, since we're
* already in recovery mode. Do this now, so that powering off after
* inserting an invalid disk doesn't leave us stuck in recovery mode. */
VbSetRecoveryRequest(VBNV_RECOVERY_NOT_REQUESTED);
if (VBERROR_SUCCESS == retval)
break; /* Found a recovery kernel */
VbDisplayScreen(cparams, VBERROR_NO_DISK_FOUND == retval ?
VB_SCREEN_RECOVERY_INSERT : VB_SCREEN_RECOVERY_NO_GOOD, 0);
/* Scan keyboard more frequently than media, since x86 platforms don't like
* to scan USB too rapidly. */
for (i = 0; i < 4; i++) {
VbCheckDisplayKey(cparams, VbExKeyboardRead());
if (VbExIsShutdownRequested())
return VBERROR_SHUTDOWN_REQUESTED;
VbExSleepMs(REC_DELAY_INCREMENT);
}
}
return VBERROR_SUCCESS;
}
VbError_t VbSelectAndLoadKernel(VbCommonParams* cparams,
VbSelectAndLoadKernelParams* kparams) {
VbSharedDataHeader* shared = (VbSharedDataHeader*)cparams->shared_data_blob;
VbError_t retval = VBERROR_SUCCESS;
LoadKernelParams p;
uint32_t tpm_status = 0;
VBDEBUG(("VbSelectAndLoadKernel() start\n"));
/* Start timer */
shared->timer_vb_select_and_load_kernel_enter = VbExGetTimer();
VbExNvStorageRead(vnc.raw);
VbNvSetup(&vnc);
/* Clear output params in case we fail */
kparams->disk_handle = NULL;
kparams->partition_number = 0;
kparams->bootloader_address = 0;
kparams->bootloader_size = 0;
Memset(kparams->partition_guid, 0, sizeof(kparams->partition_guid));
/* Read the kernel version from the TPM. Ignore errors in recovery mode. */
tpm_status = RollbackKernelRead(&shared->kernel_version_tpm);
if (0 != tpm_status) {
VBDEBUG(("Unable to get kernel versions from TPM\n"));
if (!shared->recovery_reason) {
VbSetRecoveryRequest(VBNV_RECOVERY_RW_TPM_ERROR);
retval = VBERROR_TPM_READ_KERNEL;
goto VbSelectAndLoadKernel_exit;
}
}
shared->kernel_version_tpm_start = shared->kernel_version_tpm;
/* Fill in params for calls to LoadKernel() */
Memset(&p, 0, sizeof(p));
p.shared_data_blob = cparams->shared_data_blob;
p.shared_data_size = cparams->shared_data_size;
p.gbb_data = cparams->gbb_data;
p.gbb_size = cparams->gbb_size;
p.kernel_buffer = kparams->kernel_buffer;
p.kernel_buffer_size = kparams->kernel_buffer_size;
p.nv_context = &vnc;
p.boot_flags = 0;
if (shared->flags & VBSD_BOOT_DEV_SWITCH_ON)
p.boot_flags |= BOOT_FLAG_DEVELOPER;
/* Handle separate normal and developer firmware builds. */
#if defined(VBOOT_FIRMWARE_TYPE_NORMAL)
/* Normal-type firmware always acts like the dev switch is off. */
p.boot_flags &= ~BOOT_FLAG_DEVELOPER;
#elif defined(VBOOT_FIRMWARE_TYPE_DEVELOPER)
/* Developer-type firmware fails if the dev switch is off. */
if (!(p.boot_flags & BOOT_FLAG_DEVELOPER)) {
/* Dev firmware should be signed with a key that only verifies
* when the dev switch is on, so we should never get here. */
VBDEBUG(("Developer firmware called with dev switch off!\n"));
VbSetRecoveryRequest(VBNV_RECOVERY_RW_DEV_MISMATCH);
retval = VBERROR_DEV_FIRMWARE_SWITCH_MISMATCH;
goto VbSelectAndLoadKernel_exit;
}
#else
/* Recovery firmware, or merged normal+developer firmware. No
* need to override flags. */
#endif
/* Select boot path */
if (shared->recovery_reason) {
/* Recovery boot */
p.boot_flags |= BOOT_FLAG_RECOVERY;
retval = VbBootRecovery(cparams, &p);
VbDisplayScreen(cparams, VB_SCREEN_BLANK, 0);
} else if (p.boot_flags & BOOT_FLAG_DEVELOPER) {
/* Developer boot */
retval = VbBootDeveloper(cparams, &p);
VbDisplayScreen(cparams, VB_SCREEN_BLANK, 0);
} else {
/* Normal boot */
retval = VbBootNormal(cparams, &p);
if ((1 == shared->firmware_index) && (shared->flags & VBSD_FWB_TRIED)) {
/* Special cases for when we're trying a new firmware B. These are
* needed because firmware updates also usually change the kernel key,
* which means that the B firmware can only boot a new kernel, and the
* old firmware in A can only boot the previous kernel. */
/* Don't advance the TPM if we're trying a new firmware B, because we
* don't yet know if the new kernel will successfully boot. We still
* want to be able to fall back to the previous firmware+kernel if the
* new firmware+kernel fails. */
/* If we found only invalid kernels, reboot and try again. This allows
* us to fall back to the previous firmware+kernel instead of giving up
* and going to recovery mode right away. We'll still go to recovery
* mode if we run out of tries and the old firmware can't find a kernel
* it likes. */
if (VBERROR_INVALID_KERNEL_FOUND == retval) {
VBDEBUG(("Trying firmware B, and only found invalid kernels.\n"));
VbSetRecoveryRequest(VBNV_RECOVERY_NOT_REQUESTED);
goto VbSelectAndLoadKernel_exit;
}
} else {
/* Not trying a new firmware B. */
/* See if we need to update the TPM. */
VBDEBUG(("Checking if TPM kernel version needs advancing\n"));
if (shared->kernel_version_tpm > shared->kernel_version_tpm_start) {
tpm_status = RollbackKernelWrite(shared->kernel_version_tpm);
if (0 != tpm_status) {
VBDEBUG(("Error writing kernel versions to TPM.\n"));
VbSetRecoveryRequest(VBNV_RECOVERY_RW_TPM_ERROR);
retval = VBERROR_TPM_WRITE_KERNEL;
goto VbSelectAndLoadKernel_exit;
}
}
}
}
if (VBERROR_SUCCESS != retval)
goto VbSelectAndLoadKernel_exit;
/* Save disk parameters */
kparams->disk_handle = p.disk_handle;
kparams->partition_number = (uint32_t)p.partition_number;
kparams->bootloader_address = p.bootloader_address;
kparams->bootloader_size = (uint32_t)p.bootloader_size;
Memcpy(kparams->partition_guid, p.partition_guid,
sizeof(kparams->partition_guid));
/* Lock the kernel versions. Ignore errors in recovery mode. */
tpm_status = RollbackKernelLock();
if (0 != tpm_status) {
VBDEBUG(("Error locking kernel versions.\n"));
if (!shared->recovery_reason) {
VbSetRecoveryRequest(VBNV_RECOVERY_RW_TPM_ERROR);
retval = VBERROR_TPM_LOCK_KERNEL;
goto VbSelectAndLoadKernel_exit;
}
}
VbSelectAndLoadKernel_exit:
VbNvTeardown(&vnc);
if (vnc.raw_changed)
VbExNvStorageWrite(vnc.raw);
/* Stop timer */
shared->timer_vb_select_and_load_kernel_exit = VbExGetTimer();
VBDEBUG(("VbSelectAndLoadKernel() returning %d\n", (int)retval));
/* Pass through return value from boot path */
return retval;
}