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|
/*
* Copyright 2015 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.
*/
#include <asm/byteorder.h>
#include <endian.h>
#include <fcntl.h>
#include <getopt.h>
#include <libusb.h>
#include <openssl/sha.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#ifndef __packed
#define __packed __attribute__((packed))
#endif
#include "config_chip.h"
#include "board.h"
#include "compile_time_macros.h"
#include "misc_util.h"
#include "signed_header.h"
#include "tpm_vendor_cmds.h"
#include "upgrade_fw.h"
#include "usb_descriptor.h"
#ifdef DEBUG
#define debug printf
#else
#define debug(fmt, args...)
#endif
/*
* This file contains the source code of a Linux application used to update
* CR50 device firmware.
*
* The CR50 firmware image consists of multiple sections, of interest to this
* app are the RO and RW code sections, two of each. When firmware update
* session is established, the CR50 device reports locations of backup RW and RO
* sections (those not used by the device at the time of transfer).
*
* Based on this information this app carves out the appropriate sections form
* the full CR50 firmware binary image and sends them to the device for
* programming into flash. Once the new sections are programmed and the device
* is restarted, the new RO and RW are used if they pass verification and are
* logically newer than the existing sections.
*
* There are two ways to communicate with the CR50 device: USB and SPI (when
* this app is running on a chromebook with the CR50 device). Originally
* different protocols were used to communicate over different channels,
* starting with version 3 the same protocol is used.
*
* This app provides backwards compatibility to ensure that earlier CR50
* devices still can be updated.
*
*
* The host (either a local AP or a workstation) is the master of the firmware
* update protocol, it sends data to the cr50 device, which proceeses it and
* responds.
*
* The encapsultation format is different between the SPI and USB cases:
*
* 4 bytes 4 bytes 4 bytes variable size
* +-----------+--------------+---------------+----------~~--------------+
* + total size| block digest | dest address | data |
* +-----------+--------------+---------------+----------~~--------------+
* \ \ /
* \ \ /
* \ +-------- FW update PDU sent over SPI --------------+
* \ /
* +--------- USB frame, requires total size field ------------+
*
* The update protocol data unints (PDUs) are passed over SPI, the
* encapsulation includes integritiy verification and destination address of
* the data (more of this later). SPI transactions pretty much do not have
* size limits, whereas the USB data is sent in chunks of the size determined
* when the USB connestion is set up. This is why USB requires an additional
* encapsulation int frames to communicate the PDU size to the client side so
* that the PDU can be reassembled before passing to the programming function.
*
* In general, the protocol consists of two phases: connection establishment
* and actual image transfer.
*
* The very first PDU of the transfer session is used to establish the
* connection. The first PDU does not have any data, and the dest. address
* field is set to zero. Receiving such a PDU signals the programming function
* that the host intends to transfer a new image.
*
* The response to the first PDU varies depending on the protocol version.
*
* Version 1 is used over SPI. The response is either 4 or 1 bytes in size.
* The 4 byte response is the *base address* of the backup RW section, no
* support for RO updates. The one byte response is an error indication,
* possibly reporting flash erase failure, command format error, etc.
*
* Version 2 is used over USB. The response is 8 bytes in size. The first four
* bytes are either the *base address* of the backup RW section (still no RO
* updates), or an error code, the same as in Version 1. The second 4 bytes
* are the protocol version number (set to 2).
*
* All versions above 2 behave the same over SPI and USB.
*
* Version 3 response is 16 bytes in size. The first 4 bytes are the error code
* the second 4 bytes are the protocol version (set to 3) and then 4 byte
* *offset* of the RO section followed by the 4 byte *offset* of the RW section.
*
* Version 4 response in addition to version 3 provides header revision fields
* for active RO and RW images running on the target.
*
* Once the connection is established, the image to be programmed into flash
* is transferred to the CR50 in 1K PDUs. In versions 1 and 2 the address in
* the header is the absolute address to place the block to, in version 3 and
* later it is the offset into the flash.
*
* Protocol version 5 includes RO and RW key ID information into the first PDU
* response. The key ID could be used to tell between prod and dev signing
* modes, among other things.
*
* Protocol version 6 does not change the format of the first PDU response,
* but it indicates the target's ablitiy to channel TPM venfor commands
* through USB connection.
*
* When channeling TPM vendor commands the USB frame looks as follows:
*
* 4 bytes 4 bytes 4 bytes 2 bytes variable size
* +-----------+--------------+---------------+-----------+------~~~-------+
* + total size| block digest | EXT_CMD | Vend. sub.| data |
* +-----------+--------------+---------------+-----------+------~~~-------+
*
* Where 'Vend. sub' is the vendor subcommand, and data field is subcommand
* dependent. The target tells between update PDUs and encapsulated vendor
* subcommands by looking at the EXT_CMD value - it is set to 0xbaccd00a and
* as such is guaranteed not to be a valid update PDU destination address.
*
* The vendor command response size is not fixed, it is subcommand dependent.
*
* The CR50 device responds to each update PDU with a confirmation which is 4
* bytes in size in protocol version 2, and 1 byte in size in all other
* versions. Zero value means success, non zero value is the error code
* reported by CR50.
*
* Again, vendor command responses are subcommand specific.
*/
/* Look for Cr50 FW update interface */
#define VID USB_VID_GOOGLE
#define PID CONFIG_USB_PID
#define SUBCLASS USB_SUBCLASS_GOOGLE_CR50
#define PROTOCOL USB_PROTOCOL_GOOGLE_CR50_NON_HC_FW_UPDATE
#define FLASH_BASE 0x40000
enum exit_values {
noop = 0, /* All up to date, no update needed. */
all_updated = 1, /* Update completed, reboot required. */
rw_updated = 2, /* RO was not updated, reboot required. */
update_error = 3 /* Something went wrong. */
};
/*
* Need to create an entire TPM PDU when upgrading over /dev/tpm0 and need to
* have space to prepare the entire PDU.
*/
struct upgrade_pkt {
__be16 tag;
__be32 length;
__be32 ordinal;
__be16 subcmd;
__be32 digest;
__be32 address;
char data[0];
} __packed;
#define SIGNED_TRANSFER_SIZE 1024
#define MAX_BUF_SIZE (SIGNED_TRANSFER_SIZE + sizeof(struct upgrade_pkt))
struct usb_endpoint {
struct libusb_device_handle *devh;
uint8_t ep_num;
int chunk_len;
};
struct transfer_descriptor {
/*
* Set to true for use in an upstart script. Do not reboot after
* transfer, and do not transfer RW if versions are the same.
*
* When using in development environment it is beneficial to transfer
* RW images with the same version, as they get started based on the
* header timestamp.
*/
uint32_t upstart_mode;
/*
* offsets of RO and WR sections available for update (not currently
* active).
*/
uint32_t ro_offset;
uint32_t rw_offset;
enum transfer_type {
usb_xfer = 0,
spi_xfer = 1
} ep_type;
union {
struct usb_endpoint uep;
int tpm_fd;
};
};
static uint32_t protocol_version;
static char *progname;
static char *short_opts = ":bcfd:hsu";
static const struct option long_opts[] = {
/* name hasarg *flag val */
{"binvers", 0, NULL, 'b'},
{"corrupt", 0, NULL, 'c'},
{"device", 1, NULL, 'd'},
{"help", 0, NULL, 'h'},
{"spi", 0, NULL, 's'},
{"upstart", 0, NULL, 'u'},
{"fwver", 0, NULL, 'f'},
{NULL, 0, NULL, 0},
};
/* Prepare and transfer a block to /dev/tpm0, get a reply. */
static int tpm_send_pkt(int fd, unsigned int digest, unsigned int addr,
const void *data, int size,
void *response, size_t *response_size,
uint16_t subcmd)
{
/* Used by transfer to /dev/tpm0 */
static uint8_t outbuf[MAX_BUF_SIZE];
struct upgrade_pkt *out = (struct upgrade_pkt *)outbuf;
/* Use the same structure, it will not be filled completely. */
int len, done;
int response_offset = offsetof(struct upgrade_pkt, digest);
debug("%s: sending to %#x %d bytes\n", __func__, addr, size);
len = size + sizeof(struct upgrade_pkt);
out->tag = htobe16(0x8001);
out->length = htobe32(len);
if (subcmd <= LAST_EXTENSION_COMMAND)
out->ordinal = htobe32(CONFIG_EXTENSION_COMMAND);
else
out->ordinal = htobe32(TPM_CC_VENDOR_BIT_MASK);
out->subcmd = htobe16(subcmd);
out->digest = digest;
out->address = htobe32(addr);
memcpy(out->data, data, size);
#ifdef DEBUG
{
int i;
debug("Writing %d bytes to TPM at %x\n", len, addr);
for (i = 0; i < 20; i++)
debug("%2.2x ", outbuf[i]);
debug("\n");
}
#endif
done = write(fd, out, len);
if (done < 0) {
perror("Could not write to TPM");
return -1;
} else if (done != len) {
fprintf(stderr, "Error: Wrote %d bytes, expected to write %d\n",
done, len);
return -1;
}
/*
* Let's reuse the output buffer as the receve buffer; the combined
* size of the two structures below is sure enough for any expected
* response size.
*/
len = read(fd, outbuf, sizeof(struct upgrade_pkt) +
sizeof(struct first_response_pdu));
#ifdef DEBUG
debug("Read %d bytes from TPM\n", len);
if (len > 0) {
int i;
for (i = 0; i < len; i++)
debug("%2.2x ", outbuf[i]);
debug("\n");
}
#endif
len = len - response_offset;
if (len < 0) {
fprintf(stderr, "Problems reading from TPM, got %d bytes\n",
len + response_offset);
return -1;
}
len = MIN(len, *response_size);
memcpy(response, outbuf + response_offset, len);
*response_size = len;
return 0;
}
/* Release USB device and return error to the OS. */
static void shut_down(struct usb_endpoint *uep)
{
libusb_close(uep->devh);
libusb_exit(NULL);
exit(update_error);
}
static void usage(int errs)
{
printf("\nUsage: %s [options] <binary image>\n"
"\n"
"This updates the Cr50 RW firmware over USB.\n"
"The required argument is the full RO+RW image.\n"
"\n"
"Options:\n"
"\n"
" -b,--binvers Report versions of image's "
"RW and RO headers, do not update\n"
" -c,--corrupt Corrupt the inactive rw.\n"
" -d,--device VID:PID USB device (default %04x:%04x)\n"
" -f,--fwver Report running firmware versions.\n"
" -h,--help Show this message\n"
" -s,--spi Use /dev/tmp0 (-d is ignored)\n"
" -u,--upstart "
"Upstart mode (strict header checks)\n"
"\n", progname, VID, PID);
exit(errs ? update_error : noop);
}
/* Read file into buffer */
static uint8_t *get_file_or_die(const char *filename, size_t *len_ptr)
{
FILE *fp;
struct stat st;
uint8_t *data;
size_t len;
fp = fopen(filename, "rb");
if (!fp) {
perror(filename);
exit(update_error);
}
if (fstat(fileno(fp), &st)) {
perror("stat");
exit(update_error);
}
len = st.st_size;
data = malloc(len);
if (!data) {
perror("malloc");
exit(update_error);
}
if (1 != fread(data, st.st_size, 1, fp)) {
perror("fread");
exit(update_error);
}
fclose(fp);
*len_ptr = len;
return data;
}
#define USB_ERROR(m, r) \
fprintf(stderr, "%s:%d, %s returned %d (%s)\n", __FILE__, __LINE__, \
m, r, libusb_strerror(r))
/*
* Actual USB transfer function, the 'allow_less' flag indicates that the
* valid response could be shortef than allotted memory, the 'rxed_count'
* pointer, if provided along with 'allow_less' lets the caller know how mavy
* bytes were received.
*/
static void do_xfer(struct usb_endpoint *uep, void *outbuf, int outlen,
void *inbuf, int inlen, int allow_less,
size_t *rxed_count)
{
int r, actual;
/* Send data out */
if (outbuf && outlen) {
actual = 0;
r = libusb_bulk_transfer(uep->devh, uep->ep_num,
outbuf, outlen,
&actual, 1000);
if (r < 0) {
USB_ERROR("libusb_bulk_transfer", r);
exit(update_error);
}
if (actual != outlen) {
fprintf(stderr, "%s:%d, only sent %d/%d bytes\n",
__FILE__, __LINE__, actual, outlen);
shut_down(uep);
}
}
/* Read reply back */
if (inbuf && inlen) {
actual = 0;
r = libusb_bulk_transfer(uep->devh, uep->ep_num | 0x80,
inbuf, inlen,
&actual, 1000);
if (r < 0) {
USB_ERROR("libusb_bulk_transfer", r);
exit(update_error);
}
if ((actual != inlen) && !allow_less) {
fprintf(stderr, "%s:%d, only received %d/%d bytes\n",
__FILE__, __LINE__, actual, inlen);
shut_down(uep);
}
if (rxed_count)
*rxed_count = actual;
}
}
static void xfer(struct usb_endpoint *uep, void *outbuf,
size_t outlen, void *inbuf, size_t inlen)
{
do_xfer(uep, outbuf, outlen, inbuf, inlen, 0, NULL);
}
/* Return 0 on error, since it's never gonna be EP 0 */
static int find_endpoint(const struct libusb_interface_descriptor *iface,
struct usb_endpoint *uep)
{
const struct libusb_endpoint_descriptor *ep;
if (iface->bInterfaceClass == 255 &&
iface->bInterfaceSubClass == SUBCLASS &&
iface->bInterfaceProtocol == PROTOCOL &&
iface->bNumEndpoints) {
ep = &iface->endpoint[0];
uep->ep_num = ep->bEndpointAddress & 0x7f;
uep->chunk_len = ep->wMaxPacketSize;
return 1;
}
return 0;
}
/* Return -1 on error */
static int find_interface(struct usb_endpoint *uep)
{
int iface_num = -1;
int r, i, j;
struct libusb_device *dev;
struct libusb_config_descriptor *conf = 0;
const struct libusb_interface *iface0;
const struct libusb_interface_descriptor *iface;
dev = libusb_get_device(uep->devh);
r = libusb_get_active_config_descriptor(dev, &conf);
if (r < 0) {
USB_ERROR("libusb_get_active_config_descriptor", r);
goto out;
}
for (i = 0; i < conf->bNumInterfaces; i++) {
iface0 = &conf->interface[i];
for (j = 0; j < iface0->num_altsetting; j++) {
iface = &iface0->altsetting[j];
if (find_endpoint(iface, uep)) {
iface_num = i;
goto out;
}
}
}
out:
libusb_free_config_descriptor(conf);
return iface_num;
}
/* Returns true if parsed. */
static int parse_vidpid(const char *input, uint16_t *vid_ptr, uint16_t *pid_ptr)
{
char *copy, *s, *e = 0;
copy = strdup(input);
s = strchr(copy, ':');
if (!s)
return 0;
*s++ = '\0';
*vid_ptr = (uint16_t) strtoul(copy, &e, 16);
if (!*optarg || (e && *e))
return 0;
*pid_ptr = (uint16_t) strtoul(s, &e, 16);
if (!*optarg || (e && *e))
return 0;
return 1;
}
static void usb_findit(uint16_t vid, uint16_t pid, struct usb_endpoint *uep)
{
int iface_num, r;
memset(uep, 0, sizeof(*uep));
r = libusb_init(NULL);
if (r < 0) {
USB_ERROR("libusb_init", r);
exit(update_error);
}
printf("open_device %04x:%04x\n", vid, pid);
/* NOTE: This doesn't handle multiple matches! */
uep->devh = libusb_open_device_with_vid_pid(NULL, vid, pid);
if (!uep->devh) {
fprintf(stderr, "Can't find device\n");
exit(update_error);
}
iface_num = find_interface(uep);
if (iface_num < 0) {
fprintf(stderr, "USB FW update not supported by that device\n");
shut_down(uep);
}
if (!uep->chunk_len) {
fprintf(stderr, "wMaxPacketSize isn't valid\n");
shut_down(uep);
}
printf("found interface %d endpoint %d, chunk_len %d\n",
iface_num, uep->ep_num, uep->chunk_len);
libusb_set_auto_detach_kernel_driver(uep->devh, 1);
r = libusb_claim_interface(uep->devh, iface_num);
if (r < 0) {
USB_ERROR("libusb_claim_interface", r);
shut_down(uep);
}
printf("READY\n-------\n");
}
struct update_pdu {
uint32_t block_size; /* Total block size, include this field's size. */
struct upgrade_command cmd;
/* The actual payload goes here. */
};
static int transfer_block(struct usb_endpoint *uep, struct update_pdu *updu,
uint8_t *transfer_data_ptr, size_t payload_size)
{
size_t transfer_size;
uint32_t reply;
int actual;
int r;
/* First send the header. */
xfer(uep, updu, sizeof(*updu), NULL, 0);
/* Now send the block, chunk by chunk. */
for (transfer_size = 0; transfer_size < payload_size;) {
int chunk_size;
chunk_size = MIN(uep->chunk_len, payload_size - transfer_size);
xfer(uep, transfer_data_ptr, chunk_size, NULL, 0);
transfer_data_ptr += chunk_size;
transfer_size += chunk_size;
}
/* Now get the reply. */
r = libusb_bulk_transfer(uep->devh, uep->ep_num | 0x80,
(void *) &reply, sizeof(reply),
&actual, 1000);
if (r) {
if ((r == -7) && (protocol_version >= 2)) {
fprintf(stderr, "Timeout!\n");
return r;
}
USB_ERROR("libusb_bulk_transfer", r);
shut_down(uep);
}
if (protocol_version > 2)
reply = *((uint8_t *)&reply);
else
reply = be32toh(reply);
if (reply) {
fprintf(stderr, "Error: status %#x\n", reply);
exit(update_error);
}
return 0;
}
/**
* Transfer an image section (typically RW or RO).
*
* td - transfer descriptor to use to communicate with the target
* data_ptr - pointer at the section base in the image
* section_addr - address of the section in the target memory space
* data_len - section size
*/
static void transfer_section(struct transfer_descriptor *td,
uint8_t *data_ptr,
uint32_t section_addr,
size_t data_len)
{
/*
* Actually, we can skip trailing chunks of 0xff, as the entire
* section space must be erased before the update is attempted.
*/
while (data_len && (data_ptr[data_len - 1] == 0xff))
data_len--;
printf("sending 0x%zx bytes to %#x\n", data_len, section_addr);
while (data_len) {
size_t payload_size;
SHA_CTX ctx;
uint8_t digest[SHA_DIGEST_LENGTH];
int max_retries;
struct update_pdu updu;
/* prepare the header to prepend to the block. */
payload_size = MIN(data_len, SIGNED_TRANSFER_SIZE);
updu.block_size = htobe32(payload_size +
sizeof(struct update_pdu));
if (protocol_version <= 2)
updu.cmd.block_base = htobe32(section_addr +
FLASH_BASE);
else
updu.cmd.block_base = htobe32(section_addr);
/* Calculate the digest. */
SHA1_Init(&ctx);
SHA1_Update(&ctx, &updu.cmd.block_base,
sizeof(updu.cmd.block_base));
SHA1_Update(&ctx, data_ptr, payload_size);
SHA1_Final(digest, &ctx);
/* Copy the first few bytes. */
memcpy(&updu.cmd.block_digest, digest,
sizeof(updu.cmd.block_digest));
if (td->ep_type == usb_xfer) {
for (max_retries = 10; max_retries; max_retries--)
if (!transfer_block(&td->uep, &updu,
data_ptr, payload_size))
break;
if (!max_retries) {
fprintf(stderr,
"Failed to transfer block, %zd to go\n",
data_len);
exit(update_error);
}
} else {
uint8_t error_code[4];
size_t rxed_size = sizeof(error_code);
uint32_t block_addr;
if (protocol_version <= 2)
block_addr = section_addr + FLASH_BASE;
else
block_addr = section_addr;
/*
* A single byte response is expected, but let's give
* the driver a few extra bytes to catch cases when a
* different amount of data is transferred (which
* would indicate a synchronization problem).
*/
if (tpm_send_pkt(td->tpm_fd,
updu.cmd.block_digest,
block_addr,
data_ptr,
payload_size, error_code,
&rxed_size,
EXTENSION_FW_UPGRADE) < 0) {
fprintf(stderr,
"Failed to trasfer block, %zd to go\n",
data_len);
exit(update_error);
}
if (rxed_size != 1) {
fprintf(stderr, "Unexpected return size %zd\n",
rxed_size);
exit(update_error);
}
if (error_code[0]) {
fprintf(stderr, "Error %d\n", error_code[0]);
exit(update_error);
}
}
data_len -= payload_size;
data_ptr += payload_size;
section_addr += payload_size;
}
}
/* Information about the target */
static struct first_response_pdu targ;
/*
* Each RO or RW section of the new image can be in one of the following
* states.
*/
enum upgrade_status {
not_needed = 0, /* Version below or equal that on the target. */
not_possible, /*
* RO is newer, but can't be transferred due to
* target RW shortcomings.
*/
needed /*
* This section needs to be transferred to the
* target.
*/
};
/* This array describes all four sections of the new image. */
static struct {
const char *name;
uint32_t offset;
uint32_t size;
enum upgrade_status ustatus;
struct signed_header_version shv;
uint32_t keyid;
} sections[] = {
{"RO_A", CONFIG_RO_MEM_OFF, CONFIG_RO_SIZE},
{"RW_A", CONFIG_RW_MEM_OFF, CONFIG_RW_SIZE},
{"RO_B", CHIP_RO_B_MEM_OFF, CONFIG_RO_SIZE},
{"RW_B", CONFIG_RW_B_MEM_OFF, CONFIG_RW_SIZE}
};
/*
* Scan the new image and retrieve versions of all four sections, two RO and
* two RW.
*/
static void fetch_header_versions(const void *image)
{
size_t i;
for (i = 0; i < ARRAY_SIZE(sections); i++) {
const struct SignedHeader *h;
h = (const struct SignedHeader *)((uintptr_t)image +
sections[i].offset);
sections[i].shv.epoch = h->epoch_;
sections[i].shv.major = h->major_;
sections[i].shv.minor = h->minor_;
sections[i].keyid = h->keyid;
}
}
/* Compare to signer headers and determine which one is newer. */
static int a_newer_than_b(struct signed_header_version *a,
struct signed_header_version *b)
{
uint32_t fields[][3] = {
{a->epoch, a->major, a->minor},
{b->epoch, b->major, b->minor},
};
size_t i;
/*
* Even though header version fields are 32 bits in size, we don't
* exepect any version field ever exceed say 1000. Anything in excess
* of 1000 should is considered zero.
*
* This would cover old images where one of the RO version fields is
* the number of git patches since last tag (and is in excess of
* 4000), and images where there is no code in a section (all fields
* are set to 0xffffffff).
*/
for (i = 0; i < ARRAY_SIZE(fields[0]); i++) {
uint32_t a_value;
uint32_t b_value;
a_value = fields[0][i];
b_value = fields[1][i];
if (a_value > 4000)
a_value = 0;
if (b_value > 4000)
b_value = 0;
if (a_value != b_value)
return a_value > b_value;
}
return 0; /* All else being equal A is no newer than B. */
}
/*
* Pick sections to transfer based on information retrieved from the target,
* the new image, and the protocol version the target is running.
*/
static void pick_sections(struct transfer_descriptor *td)
{
size_t i;
for (i = 0; i < ARRAY_SIZE(sections); i++) {
uint32_t offset = sections[i].offset;
if ((offset == CONFIG_RW_MEM_OFF) ||
(offset == CONFIG_RW_B_MEM_OFF)) {
/* Skip currently active section. */
if (offset != td->rw_offset)
continue;
/*
* Ok, this would be the RW section to transfer to the
* device. Is it newer in the new image than the
* running RW section on the device?
*
* If not in 'upstart' mode - transfer even if
* versions are the same, timestamps could be
* different.
*/
if (a_newer_than_b(§ions[i].shv, &targ.shv[1]) ||
!td->upstart_mode)
sections[i].ustatus = needed;
continue;
}
/*
* RO update not supported in versions below 3, another
* invocation will be required once the RW is updated to
* handle protocol 3 or above.
*/
if (protocol_version < 3) {
sections[i].ustatus = not_possible;
continue;
}
/* Skip currently active section. */
if (offset != td->ro_offset)
continue;
/*
* Ok, this would be the RO section to transfer to the device.
* Is it newer in the new image than the running RO section on
* the device?
*/
if (a_newer_than_b(§ions[i].shv, &targ.shv[0]))
sections[i].ustatus = needed;
}
}
static void setup_connection(struct transfer_descriptor *td)
{
size_t rxed_size;
uint32_t error_code;
/*
* Need to be backwards compatible, communicate with targets running
* different protocol versions.
*/
union {
struct first_response_pdu rpdu;
uint32_t legacy_resp;
} start_resp;
/* Send start request. */
printf("start\n");
if (td->ep_type == usb_xfer) {
struct update_pdu updu;
memset(&updu, 0, sizeof(updu));
updu.block_size = htobe32(sizeof(updu));
do_xfer(&td->uep, &updu, sizeof(updu), &start_resp,
sizeof(start_resp), 1, &rxed_size);
} else {
rxed_size = sizeof(start_resp);
if (tpm_send_pkt(td->tpm_fd, 0, 0, NULL, 0,
&start_resp, &rxed_size,
EXTENSION_FW_UPGRADE) < 0) {
fprintf(stderr, "Failed to start transfer\n");
exit(update_error);
}
}
/* We got something. Check for errors in response */
if (rxed_size <= 4) {
if (td->ep_type != spi_xfer) {
size_t i;
fprintf(stderr, "Unexpected response size %zd: ",
rxed_size);
for (i = 0; i < rxed_size; i++)
fprintf(stderr, " %02x",
((uint8_t *)&start_resp)[i]);
fprintf(stderr, "\n");
exit(update_error);
}
/* This is a protocol version one response. */
protocol_version = 1;
if (rxed_size == 1) {
/* Target is reporting an error. */
error_code = *((uint8_t *) &start_resp);
} else {
/* Target reporting RW base_address. */
td->rw_offset = be32toh(start_resp.legacy_resp) -
FLASH_BASE;
error_code = 0;
}
} else {
protocol_version = be32toh(start_resp.rpdu.protocol_version);
error_code = be32toh(start_resp.rpdu.return_value);
if (protocol_version == 2) {
if (error_code > 256) {
td->rw_offset = error_code - FLASH_BASE;
error_code = 0;
}
} else {
/* All newer protocols. */
td->rw_offset = be32toh
(start_resp.rpdu.backup_rw_offset);
if (protocol_version > 3) {
size_t i;
/* Running header versions are available. */
for (i = 0; i < ARRAY_SIZE(targ.shv); i++) {
targ.shv[i].minor = be32toh
(start_resp.rpdu.shv[i].minor);
targ.shv[i].major = be32toh
(start_resp.rpdu.shv[i].major);
targ.shv[i].epoch = be32toh
(start_resp.rpdu.shv[i].epoch);
}
}
if (protocol_version > 4) {
size_t i;
for (i = 0; i < ARRAY_SIZE(targ.keyid); i++)
targ.keyid[i] = be32toh
(start_resp.rpdu.keyid[i]);
}
}
}
printf("target running protocol version %d\n", protocol_version);
if (!error_code) {
if (protocol_version > 2) {
td->ro_offset = be32toh
(start_resp.rpdu.backup_ro_offset);
printf("offsets: backup RO at %#x, backup RW at %#x\n",
td->ro_offset, td->rw_offset);
}
if (protocol_version > 4)
printf("keyids: RO 0x%08x, RW 0x%08x\n",
targ.keyid[0], targ.keyid[1]);
pick_sections(td);
return;
}
fprintf(stderr, "Target reporting error %d\n", error_code);
if (td->ep_type == usb_xfer)
shut_down(&td->uep);
exit(update_error);
}
/*
* Channel TPM extension/vendor command over USB. The payload of the USB frame
* in this case consists of the 2 byte subcommand code concatenated with the
* command body. The caller needs to indicate if a response is expected, and
* if it is - of what maximum size.
*/
static int ext_cmd_over_usb(struct usb_endpoint *uep, uint16_t subcommand,
void *cmd_body, size_t body_size,
void *resp, size_t *resp_size)
{
struct update_frame_header *ufh;
uint16_t *frame_ptr;
size_t usb_msg_size;
SHA_CTX ctx;
uint8_t digest[SHA_DIGEST_LENGTH];
usb_msg_size = sizeof(struct update_frame_header) +
sizeof(subcommand) + body_size;
ufh = malloc(usb_msg_size);
if (!ufh) {
printf("%s: failed to allocate %zd bytes\n",
__func__, usb_msg_size);
return -1;
}
ufh->block_size = htobe32(usb_msg_size);
ufh->cmd.block_base = htobe32(CONFIG_EXTENSION_COMMAND);
frame_ptr = (uint16_t *)(ufh + 1);
*frame_ptr = htobe16(subcommand);
if (body_size)
memcpy(frame_ptr + 1, cmd_body, body_size);
/* Calculate the digest. */
SHA1_Init(&ctx);
SHA1_Update(&ctx, &ufh->cmd.block_base,
usb_msg_size -
offsetof(struct update_frame_header, cmd.block_base));
SHA1_Final(digest, &ctx);
memcpy(&ufh->cmd.block_digest, digest, sizeof(ufh->cmd.block_digest));
xfer(uep, ufh, usb_msg_size, resp, resp_size ? *resp_size : 0);
free(ufh);
return 0;
}
/*
* Indicate to the target that update image transfer has been completed. Upon
* receiveing of this message the target state machine transitions into the
* 'rx_idle' state. The host may send an extension command to reset the target
* after this.
*/
static void send_done(struct usb_endpoint *uep)
{
uint32_t out;
/* Send stop request, ignoring reply. */
out = htobe32(UPGRADE_DONE);
xfer(uep, &out, sizeof(out), &out,
protocol_version < 3 ? sizeof(out) : 1);
}
/*
* Corrupt the header of the inactive rw image to make sure the system can't
* rollback
*/
static void invalidate_inactive_rw(struct transfer_descriptor *td)
{
/* Corrupt the rw image that is not running. */
uint16_t subcommand = VENDOR_CC_INVALIDATE_INACTIVE_RW;
if (td->ep_type == usb_xfer) {
send_done(&td->uep);
if (protocol_version > 5) {
ext_cmd_over_usb(&td->uep, subcommand,
NULL, 0,
NULL, 0);
printf("inactive rw corrupted\n");
}
}
}
/* Returns number of successfully transmitted image sections. */
static int transfer_and_reboot(struct transfer_descriptor *td,
uint8_t *data, size_t data_len)
{
size_t i;
int num_txed_secitons = 0;
/* By default target is reset immediately after update. */
uint16_t subcommand = VENDOR_CC_IMMEDIATE_RESET;
for (i = 0; i < ARRAY_SIZE(sections); i++)
if (sections[i].ustatus == needed) {
transfer_section(td,
data + sections[i].offset,
sections[i].offset,
sections[i].size);
num_txed_secitons++;
}
if (!num_txed_secitons) {
if (td->ep_type == usb_xfer)
send_done(&td->uep);
printf("nothing to do\n");
return 0;
}
printf("-------\nupdate complete\n");
/*
* In upstart mode or in case target is running older protocol version
* - post reset is requested.
*/
if (td->upstart_mode || (protocol_version <= 5))
subcommand = EXTENSION_POST_RESET;
if (td->ep_type == usb_xfer) {
uint32_t out;
send_done(&td->uep);
if (protocol_version > 5) {
uint8_t response;
size_t response_size;
void *presponse;
/*
* Protocol versions 6 and above use vendor command to
* communicate reset mode (immediate or posted) to the
* target.
*
* No response is expected in case of immediate reset.
*/
if (subcommand == VENDOR_CC_IMMEDIATE_RESET) {
presponse = NULL;
response_size = 0;
} else {
presponse = &response;
response_size = sizeof(response);
}
ext_cmd_over_usb(&td->uep, subcommand,
NULL, 0,
presponse, &response_size);
} else {
/*
* Send a second stop request, which should reboot
* without replying.
*/
xfer(&td->uep, &out, sizeof(out), 0, 0);
}
} else {
uint8_t response;
size_t response_size;
/* Need to send extended command for posted reboot. */
if (tpm_send_pkt(td->tpm_fd, 0, 0, NULL, 0,
&response, &response_size, subcommand) < 0) {
fprintf(stderr, "Failed to request posted reboot\n");
exit(update_error);
}
}
printf("reboot %s\n", subcommand == EXTENSION_POST_RESET ?
"request posted" : "triggered");
return num_txed_secitons;
}
static int show_headers_versions(const void *image)
{
const struct {
const char *name;
uint32_t offset;
} sections[] = {
{"RO_A", CONFIG_RO_MEM_OFF},
{"RW_A", CONFIG_RW_MEM_OFF},
{"RO_B", CHIP_RO_B_MEM_OFF},
{"RW_B", CONFIG_RW_B_MEM_OFF}
};
size_t i;
for (i = 0; i < ARRAY_SIZE(sections); i++) {
const struct SignedHeader *h;
h = (const struct SignedHeader *)((uintptr_t)image +
sections[i].offset);
printf("%s%s:%d.%d.%d", i ? " " : "", sections[i].name,
h->epoch_, h->major_, h->minor_);
}
printf("\n");
return 0;
}
int main(int argc, char *argv[])
{
struct transfer_descriptor td;
int errorcnt;
uint8_t *data = 0;
size_t data_len = 0;
uint16_t vid = VID, pid = PID;
int i;
size_t j;
int transferred_sections = 0;
int binary_vers = 0;
int show_fw_ver = 0;
int corrupt_inactive_rw;
progname = strrchr(argv[0], '/');
if (progname)
progname++;
else
progname = argv[0];
/* Usb transfer - default mode. */
memset(&td, 0, sizeof(td));
td.ep_type = usb_xfer;
errorcnt = 0;
opterr = 0; /* quiet, you */
while ((i = getopt_long(argc, argv, short_opts, long_opts, 0)) != -1) {
switch (i) {
case 'b':
binary_vers = 1;
break;
case 'd':
if (!parse_vidpid(optarg, &vid, &pid)) {
printf("Invalid argument: \"%s\"\n", optarg);
errorcnt++;
}
break;
case 'c':
corrupt_inactive_rw = 1;
break;
case 'f':
show_fw_ver = 1;
break;
case 'h':
usage(errorcnt);
break;
case 's':
td.ep_type = spi_xfer;
break;
case 'u':
td.upstart_mode = 1;
break;
case 0: /* auto-handled option */
break;
case '?':
if (optopt)
printf("Unrecognized option: -%c\n", optopt);
else
printf("Unrecognized option: %s\n",
argv[optind - 1]);
errorcnt++;
break;
case ':':
printf("Missing argument to %s\n", argv[optind - 1]);
errorcnt++;
break;
default:
printf("Internal error at %s:%d\n", __FILE__, __LINE__);
exit(update_error);
}
}
if (errorcnt)
usage(errorcnt);
if (!show_fw_ver && !corrupt_inactive_rw) {
if (optind >= argc) {
fprintf(stderr,
"\nERROR: Missing required <binary image>\n\n");
usage(1);
}
data = get_file_or_die(argv[optind], &data_len);
printf("read %zd(%#zx) bytes from %s\n",
data_len, data_len, argv[optind]);
if (data_len != CONFIG_FLASH_SIZE) {
fprintf(stderr, "Image file is not %d bytes\n",
CONFIG_FLASH_SIZE);
exit(update_error);
}
fetch_header_versions(data);
if (binary_vers)
exit(show_headers_versions(data));
}
if (td.ep_type == usb_xfer) {
usb_findit(vid, pid, &td.uep);
} else {
td.tpm_fd = open("/dev/tpm0", O_RDWR);
if (td.tpm_fd < 0) {
perror("Could not open TPM");
exit(update_error);
}
}
setup_connection(&td);
if (show_fw_ver) {
printf("Current versions:\n");
printf("RO %d.%d.%d\n", targ.shv[0].epoch, targ.shv[0].major,
targ.shv[0].minor);
printf("RW %d.%d.%d\n", targ.shv[1].epoch, targ.shv[1].major,
targ.shv[1].minor);
}
if (corrupt_inactive_rw)
invalidate_inactive_rw(&td);
if (data) {
transferred_sections = transfer_and_reboot(&td, data, data_len);
free(data);
}
if (td.ep_type == usb_xfer) {
if (!data && !corrupt_inactive_rw)
send_done(&td.uep);
libusb_close(td.uep.devh);
libusb_exit(NULL);
}
if (!transferred_sections)
return noop;
/*
* We should indicate if RO update was not done because of the
* insufficient RW version.
*/
for (j = 0; j < ARRAY_SIZE(sections); j++)
if (sections[j].ustatus == not_possible) {
/* This will allow scripting repeat attempts. */
printf("Failed to update RO, run the command again\n");
return rw_updated;
}
printf("image updated\n");
return all_updated;
}
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