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platform_bootable_recovery/updater/blockimg.cpp
Chih-hung Hsieh fafa6a6531 Merge "Fix google-explicit-constructor warnings."
2016-04-29 22:26:41 +00:00

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/*
* Copyright (C) 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <ctype.h>
#include <errno.h>
#include <dirent.h>
#include <fcntl.h>
#include <inttypes.h>
#include <linux/fs.h>
#include <pthread.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/ioctl.h>
#include <time.h>
#include <unistd.h>
#include <fec/io.h>
#include <map>
#include <memory>
#include <string>
#include <vector>
#include <android-base/parseint.h>
#include <android-base/strings.h>
#include <android-base/unique_fd.h>
#include "applypatch/applypatch.h"
#include "edify/expr.h"
#include "install.h"
#include "openssl/sha.h"
#include "minzip/Hash.h"
#include "ota_io.h"
#include "print_sha1.h"
#include "updater.h"
#define BLOCKSIZE 4096
// Set this to 0 to interpret 'erase' transfers to mean do a
// BLKDISCARD ioctl (the normal behavior). Set to 1 to interpret
// erase to mean fill the region with zeroes.
#define DEBUG_ERASE 0
#define STASH_DIRECTORY_BASE "/cache/recovery"
#define STASH_DIRECTORY_MODE 0700
#define STASH_FILE_MODE 0600
struct RangeSet {
size_t count; // Limit is INT_MAX.
size_t size;
std::vector<size_t> pos; // Actual limit is INT_MAX.
};
static std::map<std::string, RangeSet> stash_map;
static void parse_range(const std::string& range_text, RangeSet& rs) {
std::vector<std::string> pieces = android::base::Split(range_text, ",");
if (pieces.size() < 3) {
goto err;
}
size_t num;
if (!android::base::ParseUint(pieces[0].c_str(), &num, static_cast<size_t>(INT_MAX))) {
goto err;
}
if (num == 0 || num % 2) {
goto err; // must be even
} else if (num != pieces.size() - 1) {
goto err;
}
rs.pos.resize(num);
rs.count = num / 2;
rs.size = 0;
for (size_t i = 0; i < num; i += 2) {
if (!android::base::ParseUint(pieces[i+1].c_str(), &rs.pos[i],
static_cast<size_t>(INT_MAX))) {
goto err;
}
if (!android::base::ParseUint(pieces[i+2].c_str(), &rs.pos[i+1],
static_cast<size_t>(INT_MAX))) {
goto err;
}
if (rs.pos[i] >= rs.pos[i+1]) {
goto err; // empty or negative range
}
size_t sz = rs.pos[i+1] - rs.pos[i];
if (rs.size > SIZE_MAX - sz) {
goto err; // overflow
}
rs.size += sz;
}
return;
err:
fprintf(stderr, "failed to parse range '%s'\n", range_text.c_str());
exit(1);
}
static bool range_overlaps(const RangeSet& r1, const RangeSet& r2) {
for (size_t i = 0; i < r1.count; ++i) {
size_t r1_0 = r1.pos[i * 2];
size_t r1_1 = r1.pos[i * 2 + 1];
for (size_t j = 0; j < r2.count; ++j) {
size_t r2_0 = r2.pos[j * 2];
size_t r2_1 = r2.pos[j * 2 + 1];
if (!(r2_0 >= r1_1 || r1_0 >= r2_1)) {
return true;
}
}
}
return false;
}
static int read_all(int fd, uint8_t* data, size_t size) {
size_t so_far = 0;
while (so_far < size) {
ssize_t r = TEMP_FAILURE_RETRY(ota_read(fd, data+so_far, size-so_far));
if (r == -1) {
fprintf(stderr, "read failed: %s\n", strerror(errno));
return -1;
}
so_far += r;
}
return 0;
}
static int read_all(int fd, std::vector<uint8_t>& buffer, size_t size) {
return read_all(fd, buffer.data(), size);
}
static int write_all(int fd, const uint8_t* data, size_t size) {
size_t written = 0;
while (written < size) {
ssize_t w = TEMP_FAILURE_RETRY(ota_write(fd, data+written, size-written));
if (w == -1) {
fprintf(stderr, "write failed: %s\n", strerror(errno));
return -1;
}
written += w;
}
return 0;
}
static int write_all(int fd, const std::vector<uint8_t>& buffer, size_t size) {
return write_all(fd, buffer.data(), size);
}
static bool check_lseek(int fd, off64_t offset, int whence) {
off64_t rc = TEMP_FAILURE_RETRY(lseek64(fd, offset, whence));
if (rc == -1) {
fprintf(stderr, "lseek64 failed: %s\n", strerror(errno));
return false;
}
return true;
}
static void allocate(size_t size, std::vector<uint8_t>& buffer) {
// if the buffer's big enough, reuse it.
if (size <= buffer.size()) return;
buffer.resize(size);
}
struct RangeSinkState {
explicit RangeSinkState(RangeSet& rs) : tgt(rs) { };
int fd;
const RangeSet& tgt;
size_t p_block;
size_t p_remain;
};
static ssize_t RangeSinkWrite(const uint8_t* data, ssize_t size, void* token) {
RangeSinkState* rss = reinterpret_cast<RangeSinkState*>(token);
if (rss->p_remain == 0) {
fprintf(stderr, "range sink write overrun");
return 0;
}
ssize_t written = 0;
while (size > 0) {
size_t write_now = size;
if (rss->p_remain < write_now) {
write_now = rss->p_remain;
}
if (write_all(rss->fd, data, write_now) == -1) {
break;
}
data += write_now;
size -= write_now;
rss->p_remain -= write_now;
written += write_now;
if (rss->p_remain == 0) {
// move to the next block
++rss->p_block;
if (rss->p_block < rss->tgt.count) {
rss->p_remain = (rss->tgt.pos[rss->p_block * 2 + 1] -
rss->tgt.pos[rss->p_block * 2]) * BLOCKSIZE;
if (!check_lseek(rss->fd, (off64_t)rss->tgt.pos[rss->p_block*2] * BLOCKSIZE,
SEEK_SET)) {
break;
}
} else {
// we can't write any more; return how many bytes have
// been written so far.
break;
}
}
}
return written;
}
// All of the data for all the 'new' transfers is contained in one
// file in the update package, concatenated together in the order in
// which transfers.list will need it. We want to stream it out of the
// archive (it's compressed) without writing it to a temp file, but we
// can't write each section until it's that transfer's turn to go.
//
// To achieve this, we expand the new data from the archive in a
// background thread, and block that threads 'receive uncompressed
// data' function until the main thread has reached a point where we
// want some new data to be written. We signal the background thread
// with the destination for the data and block the main thread,
// waiting for the background thread to complete writing that section.
// Then it signals the main thread to wake up and goes back to
// blocking waiting for a transfer.
//
// NewThreadInfo is the struct used to pass information back and forth
// between the two threads. When the main thread wants some data
// written, it sets rss to the destination location and signals the
// condition. When the background thread is done writing, it clears
// rss and signals the condition again.
struct NewThreadInfo {
ZipArchive* za;
const ZipEntry* entry;
RangeSinkState* rss;
pthread_mutex_t mu;
pthread_cond_t cv;
};
static bool receive_new_data(const unsigned char* data, int size, void* cookie) {
NewThreadInfo* nti = reinterpret_cast<NewThreadInfo*>(cookie);
while (size > 0) {
// Wait for nti->rss to be non-null, indicating some of this
// data is wanted.
pthread_mutex_lock(&nti->mu);
while (nti->rss == nullptr) {
pthread_cond_wait(&nti->cv, &nti->mu);
}
pthread_mutex_unlock(&nti->mu);
// At this point nti->rss is set, and we own it. The main
// thread is waiting for it to disappear from nti.
ssize_t written = RangeSinkWrite(data, size, nti->rss);
data += written;
size -= written;
if (nti->rss->p_block == nti->rss->tgt.count) {
// we have written all the bytes desired by this rss.
pthread_mutex_lock(&nti->mu);
nti->rss = nullptr;
pthread_cond_broadcast(&nti->cv);
pthread_mutex_unlock(&nti->mu);
}
}
return true;
}
static void* unzip_new_data(void* cookie) {
NewThreadInfo* nti = (NewThreadInfo*) cookie;
mzProcessZipEntryContents(nti->za, nti->entry, receive_new_data, nti);
return nullptr;
}
static int ReadBlocks(const RangeSet& src, std::vector<uint8_t>& buffer, int fd) {
size_t p = 0;
uint8_t* data = buffer.data();
for (size_t i = 0; i < src.count; ++i) {
if (!check_lseek(fd, (off64_t) src.pos[i * 2] * BLOCKSIZE, SEEK_SET)) {
return -1;
}
size_t size = (src.pos[i * 2 + 1] - src.pos[i * 2]) * BLOCKSIZE;
if (read_all(fd, data + p, size) == -1) {
return -1;
}
p += size;
}
return 0;
}
static int WriteBlocks(const RangeSet& tgt, const std::vector<uint8_t>& buffer, int fd) {
const uint8_t* data = buffer.data();
size_t p = 0;
for (size_t i = 0; i < tgt.count; ++i) {
if (!check_lseek(fd, (off64_t) tgt.pos[i * 2] * BLOCKSIZE, SEEK_SET)) {
return -1;
}
size_t size = (tgt.pos[i * 2 + 1] - tgt.pos[i * 2]) * BLOCKSIZE;
if (write_all(fd, data + p, size) == -1) {
return -1;
}
p += size;
}
return 0;
}
// Parameters for transfer list command functions
struct CommandParameters {
std::vector<std::string> tokens;
size_t cpos;
const char* cmdname;
const char* cmdline;
std::string freestash;
std::string stashbase;
bool canwrite;
int createdstash;
android::base::unique_fd fd;
bool foundwrites;
bool isunresumable;
int version;
size_t written;
NewThreadInfo nti;
pthread_t thread;
std::vector<uint8_t> buffer;
uint8_t* patch_start;
};
// Do a source/target load for move/bsdiff/imgdiff in version 1.
// We expect to parse the remainder of the parameter tokens as:
//
// <src_range> <tgt_range>
//
// The source range is loaded into the provided buffer, reallocating
// it to make it larger if necessary.
static int LoadSrcTgtVersion1(CommandParameters& params, RangeSet& tgt, size_t& src_blocks,
std::vector<uint8_t>& buffer, int fd) {
if (params.cpos + 1 >= params.tokens.size()) {
fprintf(stderr, "invalid parameters\n");
return -1;
}
// <src_range>
RangeSet src;
parse_range(params.tokens[params.cpos++], src);
// <tgt_range>
parse_range(params.tokens[params.cpos++], tgt);
allocate(src.size * BLOCKSIZE, buffer);
int rc = ReadBlocks(src, buffer, fd);
src_blocks = src.size;
return rc;
}
static int VerifyBlocks(const std::string& expected, const std::vector<uint8_t>& buffer,
const size_t blocks, bool printerror) {
uint8_t digest[SHA_DIGEST_LENGTH];
const uint8_t* data = buffer.data();
SHA1(data, blocks * BLOCKSIZE, digest);
std::string hexdigest = print_sha1(digest);
if (hexdigest != expected) {
if (printerror) {
fprintf(stderr, "failed to verify blocks (expected %s, read %s)\n",
expected.c_str(), hexdigest.c_str());
}
return -1;
}
return 0;
}
static std::string GetStashFileName(const std::string& base, const std::string& id,
const std::string& postfix) {
if (base.empty()) {
return "";
}
std::string fn(STASH_DIRECTORY_BASE);
fn += "/" + base + "/" + id + postfix;
return fn;
}
typedef void (*StashCallback)(const std::string&, void*);
// Does a best effort enumeration of stash files. Ignores possible non-file
// items in the stash directory and continues despite of errors. Calls the
// 'callback' function for each file and passes 'data' to the function as a
// parameter.
static void EnumerateStash(const std::string& dirname, StashCallback callback, void* data) {
if (dirname.empty() || callback == nullptr) {
return;
}
std::unique_ptr<DIR, int(*)(DIR*)> directory(opendir(dirname.c_str()), closedir);
if (directory == nullptr) {
if (errno != ENOENT) {
fprintf(stderr, "opendir \"%s\" failed: %s\n", dirname.c_str(), strerror(errno));
}
return;
}
struct dirent* item;
while ((item = readdir(directory.get())) != nullptr) {
if (item->d_type != DT_REG) {
continue;
}
std::string fn = dirname + "/" + std::string(item->d_name);
callback(fn, data);
}
}
static void UpdateFileSize(const std::string& fn, void* data) {
if (fn.empty() || !data) {
return;
}
struct stat sb;
if (stat(fn.c_str(), &sb) == -1) {
fprintf(stderr, "stat \"%s\" failed: %s\n", fn.c_str(), strerror(errno));
return;
}
int* size = reinterpret_cast<int*>(data);
*size += sb.st_size;
}
// Deletes the stash directory and all files in it. Assumes that it only
// contains files. There is nothing we can do about unlikely, but possible
// errors, so they are merely logged.
static void DeleteFile(const std::string& fn, void* /* data */) {
if (!fn.empty()) {
fprintf(stderr, "deleting %s\n", fn.c_str());
if (unlink(fn.c_str()) == -1 && errno != ENOENT) {
fprintf(stderr, "unlink \"%s\" failed: %s\n", fn.c_str(), strerror(errno));
}
}
}
static void DeletePartial(const std::string& fn, void* data) {
if (android::base::EndsWith(fn, ".partial")) {
DeleteFile(fn, data);
}
}
static void DeleteStash(const std::string& base) {
if (base.empty()) {
return;
}
fprintf(stderr, "deleting stash %s\n", base.c_str());
std::string dirname = GetStashFileName(base, "", "");
EnumerateStash(dirname, DeleteFile, nullptr);
if (rmdir(dirname.c_str()) == -1) {
if (errno != ENOENT && errno != ENOTDIR) {
fprintf(stderr, "rmdir \"%s\" failed: %s\n", dirname.c_str(), strerror(errno));
}
}
}
static int LoadStash(CommandParameters& params, const std::string& base, const std::string& id,
bool verify, size_t* blocks, std::vector<uint8_t>& buffer, bool printnoent) {
// In verify mode, if source range_set was saved for the given hash,
// check contents in the source blocks first. If the check fails,
// search for the stashed files on /cache as usual.
if (!params.canwrite) {
if (stash_map.find(id) != stash_map.end()) {
const RangeSet& src = stash_map[id];
allocate(src.size * BLOCKSIZE, buffer);
if (ReadBlocks(src, buffer, params.fd) == -1) {
fprintf(stderr, "failed to read source blocks in stash map.\n");
return -1;
}
if (VerifyBlocks(id, buffer, src.size, true) != 0) {
fprintf(stderr, "failed to verify loaded source blocks in stash map.\n");
return -1;
}
return 0;
}
}
if (base.empty()) {
return -1;
}
size_t blockcount = 0;
if (!blocks) {
blocks = &blockcount;
}
std::string fn = GetStashFileName(base, id, "");
struct stat sb;
int res = stat(fn.c_str(), &sb);
if (res == -1) {
if (errno != ENOENT || printnoent) {
fprintf(stderr, "stat \"%s\" failed: %s\n", fn.c_str(), strerror(errno));
}
return -1;
}
fprintf(stderr, " loading %s\n", fn.c_str());
if ((sb.st_size % BLOCKSIZE) != 0) {
fprintf(stderr, "%s size %" PRId64 " not multiple of block size %d",
fn.c_str(), static_cast<int64_t>(sb.st_size), BLOCKSIZE);
return -1;
}
android::base::unique_fd fd(TEMP_FAILURE_RETRY(ota_open(fn.c_str(), O_RDONLY)));
if (fd == -1) {
fprintf(stderr, "open \"%s\" failed: %s\n", fn.c_str(), strerror(errno));
return -1;
}
allocate(sb.st_size, buffer);
if (read_all(fd, buffer, sb.st_size) == -1) {
return -1;
}
*blocks = sb.st_size / BLOCKSIZE;
if (verify && VerifyBlocks(id, buffer, *blocks, true) != 0) {
fprintf(stderr, "unexpected contents in %s\n", fn.c_str());
DeleteFile(fn, nullptr);
return -1;
}
return 0;
}
static int WriteStash(const std::string& base, const std::string& id, int blocks,
std::vector<uint8_t>& buffer, bool checkspace, bool *exists) {
if (base.empty()) {
return -1;
}
if (checkspace && CacheSizeCheck(blocks * BLOCKSIZE) != 0) {
fprintf(stderr, "not enough space to write stash\n");
return -1;
}
std::string fn = GetStashFileName(base, id, ".partial");
std::string cn = GetStashFileName(base, id, "");
if (exists) {
struct stat sb;
int res = stat(cn.c_str(), &sb);
if (res == 0) {
// The file already exists and since the name is the hash of the contents,
// it's safe to assume the contents are identical (accidental hash collisions
// are unlikely)
fprintf(stderr, " skipping %d existing blocks in %s\n", blocks, cn.c_str());
*exists = true;
return 0;
}
*exists = false;
}
fprintf(stderr, " writing %d blocks to %s\n", blocks, cn.c_str());
android::base::unique_fd fd(TEMP_FAILURE_RETRY(ota_open(fn.c_str(),
O_WRONLY | O_CREAT | O_TRUNC,
STASH_FILE_MODE)));
if (fd == -1) {
fprintf(stderr, "failed to create \"%s\": %s\n", fn.c_str(), strerror(errno));
return -1;
}
if (write_all(fd, buffer, blocks * BLOCKSIZE) == -1) {
return -1;
}
if (ota_fsync(fd) == -1) {
fprintf(stderr, "fsync \"%s\" failed: %s\n", fn.c_str(), strerror(errno));
return -1;
}
if (rename(fn.c_str(), cn.c_str()) == -1) {
fprintf(stderr, "rename(\"%s\", \"%s\") failed: %s\n", fn.c_str(), cn.c_str(),
strerror(errno));
return -1;
}
std::string dname = GetStashFileName(base, "", "");
android::base::unique_fd dfd(TEMP_FAILURE_RETRY(ota_open(dname.c_str(),
O_RDONLY | O_DIRECTORY)));
if (dfd == -1) {
fprintf(stderr, "failed to open \"%s\" failed: %s\n", dname.c_str(), strerror(errno));
return -1;
}
if (ota_fsync(dfd) == -1) {
fprintf(stderr, "fsync \"%s\" failed: %s\n", dname.c_str(), strerror(errno));
return -1;
}
return 0;
}
// Creates a directory for storing stash files and checks if the /cache partition
// hash enough space for the expected amount of blocks we need to store. Returns
// >0 if we created the directory, zero if it existed already, and <0 of failure.
static int CreateStash(State* state, int maxblocks, const char* blockdev, std::string& base) {
if (blockdev == nullptr) {
return -1;
}
// Stash directory should be different for each partition to avoid conflicts
// when updating multiple partitions at the same time, so we use the hash of
// the block device name as the base directory
uint8_t digest[SHA_DIGEST_LENGTH];
SHA1(reinterpret_cast<const uint8_t*>(blockdev), strlen(blockdev), digest);
base = print_sha1(digest);
std::string dirname = GetStashFileName(base, "", "");
struct stat sb;
int res = stat(dirname.c_str(), &sb);
if (res == -1 && errno != ENOENT) {
ErrorAbort(state, "stat \"%s\" failed: %s\n", dirname.c_str(), strerror(errno));
return -1;
} else if (res != 0) {
fprintf(stderr, "creating stash %s\n", dirname.c_str());
res = mkdir(dirname.c_str(), STASH_DIRECTORY_MODE);
if (res != 0) {
ErrorAbort(state, "mkdir \"%s\" failed: %s\n", dirname.c_str(), strerror(errno));
return -1;
}
if (CacheSizeCheck(maxblocks * BLOCKSIZE) != 0) {
ErrorAbort(state, "not enough space for stash\n");
return -1;
}
return 1; // Created directory
}
fprintf(stderr, "using existing stash %s\n", dirname.c_str());
// If the directory already exists, calculate the space already allocated to
// stash files and check if there's enough for all required blocks. Delete any
// partially completed stash files first.
EnumerateStash(dirname, DeletePartial, nullptr);
int size = 0;
EnumerateStash(dirname, UpdateFileSize, &size);
size = maxblocks * BLOCKSIZE - size;
if (size > 0 && CacheSizeCheck(size) != 0) {
ErrorAbort(state, "not enough space for stash (%d more needed)\n", size);
return -1;
}
return 0; // Using existing directory
}
static int SaveStash(CommandParameters& params, const std::string& base,
std::vector<uint8_t>& buffer, int fd, bool usehash) {
// <stash_id> <src_range>
if (params.cpos + 1 >= params.tokens.size()) {
fprintf(stderr, "missing id and/or src range fields in stash command\n");
return -1;
}
const std::string& id = params.tokens[params.cpos++];
size_t blocks = 0;
if (usehash && LoadStash(params, base, id, true, &blocks, buffer, false) == 0) {
// Stash file already exists and has expected contents. Do not
// read from source again, as the source may have been already
// overwritten during a previous attempt.
return 0;
}
RangeSet src;
parse_range(params.tokens[params.cpos++], src);
allocate(src.size * BLOCKSIZE, buffer);
if (ReadBlocks(src, buffer, fd) == -1) {
return -1;
}
blocks = src.size;
if (usehash && VerifyBlocks(id, buffer, blocks, true) != 0) {
// Source blocks have unexpected contents. If we actually need this
// data later, this is an unrecoverable error. However, the command
// that uses the data may have already completed previously, so the
// possible failure will occur during source block verification.
fprintf(stderr, "failed to load source blocks for stash %s\n", id.c_str());
return 0;
}
// In verify mode, save source range_set instead of stashing blocks.
if (!params.canwrite && usehash) {
stash_map[id] = src;
return 0;
}
fprintf(stderr, "stashing %zu blocks to %s\n", blocks, id.c_str());
return WriteStash(base, id, blocks, buffer, false, nullptr);
}
static int FreeStash(const std::string& base, const std::string& id) {
if (base.empty() || id.empty()) {
return -1;
}
std::string fn = GetStashFileName(base, id, "");
DeleteFile(fn, nullptr);
return 0;
}
static void MoveRange(std::vector<uint8_t>& dest, const RangeSet& locs,
const std::vector<uint8_t>& source) {
// source contains packed data, which we want to move to the
// locations given in locs in the dest buffer. source and dest
// may be the same buffer.
const uint8_t* from = source.data();
uint8_t* to = dest.data();
size_t start = locs.size;
for (int i = locs.count-1; i >= 0; --i) {
size_t blocks = locs.pos[i*2+1] - locs.pos[i*2];
start -= blocks;
memmove(to + (locs.pos[i*2] * BLOCKSIZE), from + (start * BLOCKSIZE),
blocks * BLOCKSIZE);
}
}
// Do a source/target load for move/bsdiff/imgdiff in version 2.
// We expect to parse the remainder of the parameter tokens as one of:
//
// <tgt_range> <src_block_count> <src_range>
// (loads data from source image only)
//
// <tgt_range> <src_block_count> - <[stash_id:stash_range] ...>
// (loads data from stashes only)
//
// <tgt_range> <src_block_count> <src_range> <src_loc> <[stash_id:stash_range] ...>
// (loads data from both source image and stashes)
//
// On return, buffer is filled with the loaded source data (rearranged
// and combined with stashed data as necessary). buffer may be
// reallocated if needed to accommodate the source data. *tgt is the
// target RangeSet. Any stashes required are loaded using LoadStash.
static int LoadSrcTgtVersion2(CommandParameters& params, RangeSet& tgt, size_t& src_blocks,
std::vector<uint8_t>& buffer, int fd, const std::string& stashbase, bool* overlap) {
// At least it needs to provide three parameters: <tgt_range>,
// <src_block_count> and "-"/<src_range>.
if (params.cpos + 2 >= params.tokens.size()) {
fprintf(stderr, "invalid parameters\n");
return -1;
}
// <tgt_range>
parse_range(params.tokens[params.cpos++], tgt);
// <src_block_count>
const std::string& token = params.tokens[params.cpos++];
if (!android::base::ParseUint(token.c_str(), &src_blocks)) {
fprintf(stderr, "invalid src_block_count \"%s\"\n", token.c_str());
return -1;
}
allocate(src_blocks * BLOCKSIZE, buffer);
// "-" or <src_range> [<src_loc>]
if (params.tokens[params.cpos] == "-") {
// no source ranges, only stashes
params.cpos++;
} else {
RangeSet src;
parse_range(params.tokens[params.cpos++], src);
int res = ReadBlocks(src, buffer, fd);
if (overlap) {
*overlap = range_overlaps(src, tgt);
}
if (res == -1) {
return -1;
}
if (params.cpos >= params.tokens.size()) {
// no stashes, only source range
return 0;
}
RangeSet locs;
parse_range(params.tokens[params.cpos++], locs);
MoveRange(buffer, locs, buffer);
}
// <[stash_id:stash_range]>
while (params.cpos < params.tokens.size()) {
// Each word is a an index into the stash table, a colon, and
// then a rangeset describing where in the source block that
// stashed data should go.
std::vector<std::string> tokens = android::base::Split(params.tokens[params.cpos++], ":");
if (tokens.size() != 2) {
fprintf(stderr, "invalid parameter\n");
return -1;
}
std::vector<uint8_t> stash;
int res = LoadStash(params, stashbase, tokens[0], false, nullptr, stash, true);
if (res == -1) {
// These source blocks will fail verification if used later, but we
// will let the caller decide if this is a fatal failure
fprintf(stderr, "failed to load stash %s\n", tokens[0].c_str());
continue;
}
RangeSet locs;
parse_range(tokens[1], locs);
MoveRange(buffer, locs, stash);
}
return 0;
}
// Do a source/target load for move/bsdiff/imgdiff in version 3.
//
// Parameters are the same as for LoadSrcTgtVersion2, except for 'onehash', which
// tells the function whether to expect separate source and targe block hashes, or
// if they are both the same and only one hash should be expected, and
// 'isunresumable', which receives a non-zero value if block verification fails in
// a way that the update cannot be resumed anymore.
//
// If the function is unable to load the necessary blocks or their contents don't
// match the hashes, the return value is -1 and the command should be aborted.
//
// If the return value is 1, the command has already been completed according to
// the contents of the target blocks, and should not be performed again.
//
// If the return value is 0, source blocks have expected content and the command
// can be performed.
static int LoadSrcTgtVersion3(CommandParameters& params, RangeSet& tgt, size_t& src_blocks,
bool onehash, bool& overlap) {
if (params.cpos >= params.tokens.size()) {
fprintf(stderr, "missing source hash\n");
return -1;
}
std::string srchash = params.tokens[params.cpos++];
std::string tgthash;
if (onehash) {
tgthash = srchash;
} else {
if (params.cpos >= params.tokens.size()) {
fprintf(stderr, "missing target hash\n");
return -1;
}
tgthash = params.tokens[params.cpos++];
}
if (LoadSrcTgtVersion2(params, tgt, src_blocks, params.buffer, params.fd,
params.stashbase, &overlap) == -1) {
return -1;
}
std::vector<uint8_t> tgtbuffer(tgt.size * BLOCKSIZE);
if (ReadBlocks(tgt, tgtbuffer, params.fd) == -1) {
return -1;
}
if (VerifyBlocks(tgthash, tgtbuffer, tgt.size, false) == 0) {
// Target blocks already have expected content, command should be skipped
return 1;
}
if (VerifyBlocks(srchash, params.buffer, src_blocks, true) == 0) {
// If source and target blocks overlap, stash the source blocks so we can
// resume from possible write errors. In verify mode, we can skip stashing
// because the source blocks won't be overwritten.
if (overlap && params.canwrite) {
fprintf(stderr, "stashing %zu overlapping blocks to %s\n", src_blocks,
srchash.c_str());
bool stash_exists = false;
if (WriteStash(params.stashbase, srchash, src_blocks, params.buffer, true,
&stash_exists) != 0) {
fprintf(stderr, "failed to stash overlapping source blocks\n");
return -1;
}
// Can be deleted when the write has completed
if (!stash_exists) {
params.freestash = srchash;
}
}
// Source blocks have expected content, command can proceed
return 0;
}
if (overlap && LoadStash(params, params.stashbase, srchash, true, nullptr, params.buffer,
true) == 0) {
// Overlapping source blocks were previously stashed, command can proceed.
// We are recovering from an interrupted command, so we don't know if the
// stash can safely be deleted after this command.
return 0;
}
// Valid source data not available, update cannot be resumed
fprintf(stderr, "partition has unexpected contents\n");
params.isunresumable = true;
return -1;
}
static int PerformCommandMove(CommandParameters& params) {
size_t blocks = 0;
bool overlap = false;
int status = 0;
RangeSet tgt;
if (params.version == 1) {
status = LoadSrcTgtVersion1(params, tgt, blocks, params.buffer, params.fd);
} else if (params.version == 2) {
status = LoadSrcTgtVersion2(params, tgt, blocks, params.buffer, params.fd,
params.stashbase, nullptr);
} else if (params.version >= 3) {
status = LoadSrcTgtVersion3(params, tgt, blocks, true, overlap);
}
if (status == -1) {
fprintf(stderr, "failed to read blocks for move\n");
return -1;
}
if (status == 0) {
params.foundwrites = true;
} else if (params.foundwrites) {
fprintf(stderr, "warning: commands executed out of order [%s]\n", params.cmdname);
}
if (params.canwrite) {
if (status == 0) {
fprintf(stderr, " moving %zu blocks\n", blocks);
if (WriteBlocks(tgt, params.buffer, params.fd) == -1) {
return -1;
}
} else {
fprintf(stderr, "skipping %zu already moved blocks\n", blocks);
}
}
if (!params.freestash.empty()) {
FreeStash(params.stashbase, params.freestash);
params.freestash.clear();
}
params.written += tgt.size;
return 0;
}
static int PerformCommandStash(CommandParameters& params) {
return SaveStash(params, params.stashbase, params.buffer, params.fd,
(params.version >= 3));
}
static int PerformCommandFree(CommandParameters& params) {
// <stash_id>
if (params.cpos >= params.tokens.size()) {
fprintf(stderr, "missing stash id in free command\n");
return -1;
}
const std::string& id = params.tokens[params.cpos++];
if (!params.canwrite && stash_map.find(id) != stash_map.end()) {
stash_map.erase(id);
return 0;
}
if (params.createdstash || params.canwrite) {
return FreeStash(params.stashbase, id);
}
return 0;
}
static int PerformCommandZero(CommandParameters& params) {
if (params.cpos >= params.tokens.size()) {
fprintf(stderr, "missing target blocks for zero\n");
return -1;
}
RangeSet tgt;
parse_range(params.tokens[params.cpos++], tgt);
fprintf(stderr, " zeroing %zu blocks\n", tgt.size);
allocate(BLOCKSIZE, params.buffer);
memset(params.buffer.data(), 0, BLOCKSIZE);
if (params.canwrite) {
for (size_t i = 0; i < tgt.count; ++i) {
if (!check_lseek(params.fd, (off64_t) tgt.pos[i * 2] * BLOCKSIZE, SEEK_SET)) {
return -1;
}
for (size_t j = tgt.pos[i * 2]; j < tgt.pos[i * 2 + 1]; ++j) {
if (write_all(params.fd, params.buffer, BLOCKSIZE) == -1) {
return -1;
}
}
}
}
if (params.cmdname[0] == 'z') {
// Update only for the zero command, as the erase command will call
// this if DEBUG_ERASE is defined.
params.written += tgt.size;
}
return 0;
}
static int PerformCommandNew(CommandParameters& params) {
if (params.cpos >= params.tokens.size()) {
fprintf(stderr, "missing target blocks for new\n");
return -1;
}
RangeSet tgt;
parse_range(params.tokens[params.cpos++], tgt);
if (params.canwrite) {
fprintf(stderr, " writing %zu blocks of new data\n", tgt.size);
RangeSinkState rss(tgt);
rss.fd = params.fd;
rss.p_block = 0;
rss.p_remain = (tgt.pos[1] - tgt.pos[0]) * BLOCKSIZE;
if (!check_lseek(params.fd, (off64_t) tgt.pos[0] * BLOCKSIZE, SEEK_SET)) {
return -1;
}
pthread_mutex_lock(&params.nti.mu);
params.nti.rss = &rss;
pthread_cond_broadcast(&params.nti.cv);
while (params.nti.rss) {
pthread_cond_wait(&params.nti.cv, &params.nti.mu);
}
pthread_mutex_unlock(&params.nti.mu);
}
params.written += tgt.size;
return 0;
}
static int PerformCommandDiff(CommandParameters& params) {
// <offset> <length>
if (params.cpos + 1 >= params.tokens.size()) {
fprintf(stderr, "missing patch offset or length for %s\n", params.cmdname);
return -1;
}
size_t offset;
if (!android::base::ParseUint(params.tokens[params.cpos++].c_str(), &offset)) {
fprintf(stderr, "invalid patch offset\n");
return -1;
}
size_t len;
if (!android::base::ParseUint(params.tokens[params.cpos++].c_str(), &len)) {
fprintf(stderr, "invalid patch offset\n");
return -1;
}
RangeSet tgt;
size_t blocks = 0;
bool overlap = false;
int status = 0;
if (params.version == 1) {
status = LoadSrcTgtVersion1(params, tgt, blocks, params.buffer, params.fd);
} else if (params.version == 2) {
status = LoadSrcTgtVersion2(params, tgt, blocks, params.buffer, params.fd,
params.stashbase, nullptr);
} else if (params.version >= 3) {
status = LoadSrcTgtVersion3(params, tgt, blocks, false, overlap);
}
if (status == -1) {
fprintf(stderr, "failed to read blocks for diff\n");
return -1;
}
if (status == 0) {
params.foundwrites = true;
} else if (params.foundwrites) {
fprintf(stderr, "warning: commands executed out of order [%s]\n", params.cmdname);
}
if (params.canwrite) {
if (status == 0) {
fprintf(stderr, "patching %zu blocks to %zu\n", blocks, tgt.size);
Value patch_value;
patch_value.type = VAL_BLOB;
patch_value.size = len;
patch_value.data = (char*) (params.patch_start + offset);
RangeSinkState rss(tgt);
rss.fd = params.fd;
rss.p_block = 0;
rss.p_remain = (tgt.pos[1] - tgt.pos[0]) * BLOCKSIZE;
if (!check_lseek(params.fd, (off64_t) tgt.pos[0] * BLOCKSIZE, SEEK_SET)) {
return -1;
}
if (params.cmdname[0] == 'i') { // imgdiff
ApplyImagePatch(params.buffer.data(), blocks * BLOCKSIZE, &patch_value,
&RangeSinkWrite, &rss, nullptr, nullptr);
} else {
ApplyBSDiffPatch(params.buffer.data(), blocks * BLOCKSIZE, &patch_value, 0,
&RangeSinkWrite, &rss, nullptr);
}
// We expect the output of the patcher to fill the tgt ranges exactly.
if (rss.p_block != tgt.count || rss.p_remain != 0) {
fprintf(stderr, "range sink underrun?\n");
}
} else {
fprintf(stderr, "skipping %zu blocks already patched to %zu [%s]\n",
blocks, tgt.size, params.cmdline);
}
}
if (!params.freestash.empty()) {
FreeStash(params.stashbase, params.freestash);
params.freestash.clear();
}
params.written += tgt.size;
return 0;
}
static int PerformCommandErase(CommandParameters& params) {
if (DEBUG_ERASE) {
return PerformCommandZero(params);
}
struct stat sb;
if (fstat(params.fd, &sb) == -1) {
fprintf(stderr, "failed to fstat device to erase: %s\n", strerror(errno));
return -1;
}
if (!S_ISBLK(sb.st_mode)) {
fprintf(stderr, "not a block device; skipping erase\n");
return -1;
}
if (params.cpos >= params.tokens.size()) {
fprintf(stderr, "missing target blocks for erase\n");
return -1;
}
RangeSet tgt;
parse_range(params.tokens[params.cpos++], tgt);
if (params.canwrite) {
fprintf(stderr, " erasing %zu blocks\n", tgt.size);
for (size_t i = 0; i < tgt.count; ++i) {
uint64_t blocks[2];
// offset in bytes
blocks[0] = tgt.pos[i * 2] * (uint64_t) BLOCKSIZE;
// length in bytes
blocks[1] = (tgt.pos[i * 2 + 1] - tgt.pos[i * 2]) * (uint64_t) BLOCKSIZE;
if (ioctl(params.fd, BLKDISCARD, &blocks) == -1) {
fprintf(stderr, "BLKDISCARD ioctl failed: %s\n", strerror(errno));
return -1;
}
}
}
return 0;
}
// Definitions for transfer list command functions
typedef int (*CommandFunction)(CommandParameters&);
struct Command {
const char* name;
CommandFunction f;
};
// CompareCommands and CompareCommandNames are for the hash table
static int CompareCommands(const void* c1, const void* c2) {
return strcmp(((const Command*) c1)->name, ((const Command*) c2)->name);
}
static int CompareCommandNames(const void* c1, const void* c2) {
return strcmp(((const Command*) c1)->name, (const char*) c2);
}
// HashString is used to hash command names for the hash table
static unsigned int HashString(const char *s) {
unsigned int hash = 0;
if (s) {
while (*s) {
hash = hash * 33 + *s++;
}
}
return hash;
}
// args:
// - block device (or file) to modify in-place
// - transfer list (blob)
// - new data stream (filename within package.zip)
// - patch stream (filename within package.zip, must be uncompressed)
static Value* PerformBlockImageUpdate(const char* name, State* state, int /* argc */, Expr* argv[],
const Command* commands, size_t cmdcount, bool dryrun) {
CommandParameters params = {};
params.canwrite = !dryrun;
fprintf(stderr, "performing %s\n", dryrun ? "verification" : "update");
Value* blockdev_filename = nullptr;
Value* transfer_list_value = nullptr;
Value* new_data_fn = nullptr;
Value* patch_data_fn = nullptr;
if (ReadValueArgs(state, argv, 4, &blockdev_filename, &transfer_list_value,
&new_data_fn, &patch_data_fn) < 0) {
return StringValue(strdup(""));
}
std::unique_ptr<Value, decltype(&FreeValue)> blockdev_filename_holder(blockdev_filename,
FreeValue);
std::unique_ptr<Value, decltype(&FreeValue)> transfer_list_value_holder(transfer_list_value,
FreeValue);
std::unique_ptr<Value, decltype(&FreeValue)> new_data_fn_holder(new_data_fn, FreeValue);
std::unique_ptr<Value, decltype(&FreeValue)> patch_data_fn_holder(patch_data_fn, FreeValue);
if (blockdev_filename->type != VAL_STRING) {
ErrorAbort(state, "blockdev_filename argument to %s must be string", name);
return StringValue(strdup(""));
}
if (transfer_list_value->type != VAL_BLOB) {
ErrorAbort(state, "transfer_list argument to %s must be blob", name);
return StringValue(strdup(""));
}
if (new_data_fn->type != VAL_STRING) {
ErrorAbort(state, "new_data_fn argument to %s must be string", name);
return StringValue(strdup(""));
}
if (patch_data_fn->type != VAL_STRING) {
ErrorAbort(state, "patch_data_fn argument to %s must be string", name);
return StringValue(strdup(""));
}
UpdaterInfo* ui = reinterpret_cast<UpdaterInfo*>(state->cookie);
if (ui == nullptr) {
return StringValue(strdup(""));
}
FILE* cmd_pipe = ui->cmd_pipe;
ZipArchive* za = ui->package_zip;
if (cmd_pipe == nullptr || za == nullptr) {
return StringValue(strdup(""));
}
const ZipEntry* patch_entry = mzFindZipEntry(za, patch_data_fn->data);
if (patch_entry == nullptr) {
fprintf(stderr, "%s(): no file \"%s\" in package", name, patch_data_fn->data);
return StringValue(strdup(""));
}
params.patch_start = ui->package_zip_addr + mzGetZipEntryOffset(patch_entry);
const ZipEntry* new_entry = mzFindZipEntry(za, new_data_fn->data);
if (new_entry == nullptr) {
fprintf(stderr, "%s(): no file \"%s\" in package", name, new_data_fn->data);
return StringValue(strdup(""));
}
params.fd.reset(TEMP_FAILURE_RETRY(ota_open(blockdev_filename->data, O_RDWR)));
if (params.fd == -1) {
fprintf(stderr, "open \"%s\" failed: %s\n", blockdev_filename->data, strerror(errno));
return StringValue(strdup(""));
}
if (params.canwrite) {
params.nti.za = za;
params.nti.entry = new_entry;
pthread_mutex_init(&params.nti.mu, nullptr);
pthread_cond_init(&params.nti.cv, nullptr);
pthread_attr_t attr;
pthread_attr_init(&attr);
pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);
int error = pthread_create(&params.thread, &attr, unzip_new_data, &params.nti);
if (error != 0) {
fprintf(stderr, "pthread_create failed: %s\n", strerror(error));
return StringValue(strdup(""));
}
}
// Copy all the lines in transfer_list_value into std::string for
// processing.
const std::string transfer_list(transfer_list_value->data, transfer_list_value->size);
std::vector<std::string> lines = android::base::Split(transfer_list, "\n");
if (lines.size() < 2) {
ErrorAbort(state, "too few lines in the transfer list [%zd]\n", lines.size());
return StringValue(strdup(""));
}
// First line in transfer list is the version number
if (!android::base::ParseInt(lines[0].c_str(), &params.version, 1, 4)) {
fprintf(stderr, "unexpected transfer list version [%s]\n", lines[0].c_str());
return StringValue(strdup(""));
}
fprintf(stderr, "blockimg version is %d\n", params.version);
// Second line in transfer list is the total number of blocks we expect to write
int total_blocks;
if (!android::base::ParseInt(lines[1].c_str(), &total_blocks, 0)) {
ErrorAbort(state, "unexpected block count [%s]\n", lines[1].c_str());
return StringValue(strdup(""));
}
if (total_blocks == 0) {
return StringValue(strdup("t"));
}
size_t start = 2;
if (params.version >= 2) {
if (lines.size() < 4) {
ErrorAbort(state, "too few lines in the transfer list [%zu]\n", lines.size());
return StringValue(strdup(""));
}
// Third line is how many stash entries are needed simultaneously
fprintf(stderr, "maximum stash entries %s\n", lines[2].c_str());
// Fourth line is the maximum number of blocks that will be stashed simultaneously
int stash_max_blocks;
if (!android::base::ParseInt(lines[3].c_str(), &stash_max_blocks, 0)) {
ErrorAbort(state, "unexpected maximum stash blocks [%s]\n", lines[3].c_str());
return StringValue(strdup(""));
}
int res = CreateStash(state, stash_max_blocks, blockdev_filename->data, params.stashbase);
if (res == -1) {
return StringValue(strdup(""));
}
params.createdstash = res;
start += 2;
}
// Build a hash table of the available commands
HashTable* cmdht = mzHashTableCreate(cmdcount, nullptr);
std::unique_ptr<HashTable, decltype(&mzHashTableFree)> cmdht_holder(cmdht, mzHashTableFree);
for (size_t i = 0; i < cmdcount; ++i) {
unsigned int cmdhash = HashString(commands[i].name);
mzHashTableLookup(cmdht, cmdhash, (void*) &commands[i], CompareCommands, true);
}
int rc = -1;
// Subsequent lines are all individual transfer commands
for (auto it = lines.cbegin() + start; it != lines.cend(); it++) {
const std::string& line_str(*it);
if (line_str.empty()) {
continue;
}
params.tokens = android::base::Split(line_str, " ");
params.cpos = 0;
params.cmdname = params.tokens[params.cpos++].c_str();
params.cmdline = line_str.c_str();
unsigned int cmdhash = HashString(params.cmdname);
const Command* cmd = reinterpret_cast<const Command*>(mzHashTableLookup(cmdht, cmdhash,
const_cast<char*>(params.cmdname), CompareCommandNames,
false));
if (cmd == nullptr) {
fprintf(stderr, "unexpected command [%s]\n", params.cmdname);
goto pbiudone;
}
if (cmd->f != nullptr && cmd->f(params) == -1) {
fprintf(stderr, "failed to execute command [%s]\n", line_str.c_str());
goto pbiudone;
}
if (params.canwrite) {
if (ota_fsync(params.fd) == -1) {
fprintf(stderr, "fsync failed: %s\n", strerror(errno));
goto pbiudone;
}
fprintf(cmd_pipe, "set_progress %.4f\n", (double) params.written / total_blocks);
fflush(cmd_pipe);
}
}
if (params.canwrite) {
pthread_join(params.thread, nullptr);
fprintf(stderr, "wrote %zu blocks; expected %d\n", params.written, total_blocks);
fprintf(stderr, "max alloc needed was %zu\n", params.buffer.size());
// Delete stash only after successfully completing the update, as it
// may contain blocks needed to complete the update later.
DeleteStash(params.stashbase);
} else {
fprintf(stderr, "verified partition contents; update may be resumed\n");
}
rc = 0;
pbiudone:
if (ota_fsync(params.fd) == -1) {
fprintf(stderr, "fsync failed: %s\n", strerror(errno));
}
// params.fd will be automatically closed because it's a unique_fd.
// Only delete the stash if the update cannot be resumed, or it's
// a verification run and we created the stash.
if (params.isunresumable || (!params.canwrite && params.createdstash)) {
DeleteStash(params.stashbase);
}
return StringValue(rc == 0 ? strdup("t") : strdup(""));
}
// The transfer list is a text file containing commands to
// transfer data from one place to another on the target
// partition. We parse it and execute the commands in order:
//
// zero [rangeset]
// - fill the indicated blocks with zeros
//
// new [rangeset]
// - fill the blocks with data read from the new_data file
//
// erase [rangeset]
// - mark the given blocks as empty
//
// move <...>
// bsdiff <patchstart> <patchlen> <...>
// imgdiff <patchstart> <patchlen> <...>
// - read the source blocks, apply a patch (or not in the
// case of move), write result to target blocks. bsdiff or
// imgdiff specifies the type of patch; move means no patch
// at all.
//
// The format of <...> differs between versions 1 and 2;
// see the LoadSrcTgtVersion{1,2}() functions for a
// description of what's expected.
//
// stash <stash_id> <src_range>
// - (version 2+ only) load the given source range and stash
// the data in the given slot of the stash table.
//
// free <stash_id>
// - (version 3+ only) free the given stash data.
//
// The creator of the transfer list will guarantee that no block
// is read (ie, used as the source for a patch or move) after it
// has been written.
//
// In version 2, the creator will guarantee that a given stash is
// loaded (with a stash command) before it's used in a
// move/bsdiff/imgdiff command.
//
// Within one command the source and target ranges may overlap so
// in general we need to read the entire source into memory before
// writing anything to the target blocks.
//
// All the patch data is concatenated into one patch_data file in
// the update package. It must be stored uncompressed because we
// memory-map it in directly from the archive. (Since patches are
// already compressed, we lose very little by not compressing
// their concatenation.)
//
// In version 3, commands that read data from the partition (i.e.
// move/bsdiff/imgdiff/stash) have one or more additional hashes
// before the range parameters, which are used to check if the
// command has already been completed and verify the integrity of
// the source data.
Value* BlockImageVerifyFn(const char* name, State* state, int argc, Expr* argv[]) {
// Commands which are not tested are set to nullptr to skip them completely
const Command commands[] = {
{ "bsdiff", PerformCommandDiff },
{ "erase", nullptr },
{ "free", PerformCommandFree },
{ "imgdiff", PerformCommandDiff },
{ "move", PerformCommandMove },
{ "new", nullptr },
{ "stash", PerformCommandStash },
{ "zero", nullptr }
};
// Perform a dry run without writing to test if an update can proceed
return PerformBlockImageUpdate(name, state, argc, argv, commands,
sizeof(commands) / sizeof(commands[0]), true);
}
Value* BlockImageUpdateFn(const char* name, State* state, int argc, Expr* argv[]) {
const Command commands[] = {
{ "bsdiff", PerformCommandDiff },
{ "erase", PerformCommandErase },
{ "free", PerformCommandFree },
{ "imgdiff", PerformCommandDiff },
{ "move", PerformCommandMove },
{ "new", PerformCommandNew },
{ "stash", PerformCommandStash },
{ "zero", PerformCommandZero }
};
return PerformBlockImageUpdate(name, state, argc, argv, commands,
sizeof(commands) / sizeof(commands[0]), false);
}
Value* RangeSha1Fn(const char* name, State* state, int /* argc */, Expr* argv[]) {
Value* blockdev_filename;
Value* ranges;
if (ReadValueArgs(state, argv, 2, &blockdev_filename, &ranges) < 0) {
return StringValue(strdup(""));
}
std::unique_ptr<Value, decltype(&FreeValue)> ranges_holder(ranges, FreeValue);
std::unique_ptr<Value, decltype(&FreeValue)> blockdev_filename_holder(blockdev_filename,
FreeValue);
if (blockdev_filename->type != VAL_STRING) {
ErrorAbort(state, "blockdev_filename argument to %s must be string", name);
return StringValue(strdup(""));
}
if (ranges->type != VAL_STRING) {
ErrorAbort(state, "ranges argument to %s must be string", name);
return StringValue(strdup(""));
}
android::base::unique_fd fd(ota_open(blockdev_filename->data, O_RDWR));
if (fd == -1) {
ErrorAbort(state, "open \"%s\" failed: %s", blockdev_filename->data, strerror(errno));
return StringValue(strdup(""));
}
RangeSet rs;
parse_range(ranges->data, rs);
SHA_CTX ctx;
SHA1_Init(&ctx);
std::vector<uint8_t> buffer(BLOCKSIZE);
for (size_t i = 0; i < rs.count; ++i) {
if (!check_lseek(fd, (off64_t)rs.pos[i*2] * BLOCKSIZE, SEEK_SET)) {
ErrorAbort(state, "failed to seek %s: %s", blockdev_filename->data, strerror(errno));
return StringValue(strdup(""));
}
for (size_t j = rs.pos[i*2]; j < rs.pos[i*2+1]; ++j) {
if (read_all(fd, buffer, BLOCKSIZE) == -1) {
ErrorAbort(state, "failed to read %s: %s", blockdev_filename->data,
strerror(errno));
return StringValue(strdup(""));
}
SHA1_Update(&ctx, buffer.data(), BLOCKSIZE);
}
}
uint8_t digest[SHA_DIGEST_LENGTH];
SHA1_Final(digest, &ctx);
return StringValue(strdup(print_sha1(digest).c_str()));
}
// This function checks if a device has been remounted R/W prior to an incremental
// OTA update. This is an common cause of update abortion. The function reads the
// 1st block of each partition and check for mounting time/count. It return string "t"
// if executes successfully and an empty string otherwise.
Value* CheckFirstBlockFn(const char* name, State* state, int argc, Expr* argv[]) {
Value* arg_filename;
if (ReadValueArgs(state, argv, 1, &arg_filename) < 0) {
return nullptr;
}
std::unique_ptr<Value, decltype(&FreeValue)> filename(arg_filename, FreeValue);
if (filename->type != VAL_STRING) {
ErrorAbort(state, "filename argument to %s must be string", name);
return StringValue(strdup(""));
}
android::base::unique_fd fd(ota_open(arg_filename->data, O_RDONLY));
if (fd == -1) {
ErrorAbort(state, "open \"%s\" failed: %s", arg_filename->data, strerror(errno));
return StringValue(strdup(""));
}
RangeSet blk0 {1 /*count*/, 1/*size*/, std::vector<size_t> {0, 1}/*position*/};
std::vector<uint8_t> block0_buffer(BLOCKSIZE);
if (ReadBlocks(blk0, block0_buffer, fd) == -1) {
ErrorAbort(state, "failed to read %s: %s", arg_filename->data, strerror(errno));
return StringValue(strdup(""));
}
// https://ext4.wiki.kernel.org/index.php/Ext4_Disk_Layout
// Super block starts from block 0, offset 0x400
// 0x2C: len32 Mount time
// 0x30: len32 Write time
// 0x34: len16 Number of mounts since the last fsck
// 0x38: len16 Magic signature 0xEF53
time_t mount_time = *reinterpret_cast<uint32_t*>(&block0_buffer[0x400+0x2C]);
uint16_t mount_count = *reinterpret_cast<uint16_t*>(&block0_buffer[0x400+0x34]);
if (mount_count > 0) {
uiPrintf(state, "Device was remounted R/W %d times\n", mount_count);
uiPrintf(state, "Last remount happened on %s", ctime(&mount_time));
}
return StringValue(strdup("t"));
}
Value* BlockImageRecoverFn(const char* name, State* state, int argc, Expr* argv[]) {
Value* arg_filename;
Value* arg_ranges;
if (ReadValueArgs(state, argv, 2, &arg_filename, &arg_ranges) < 0) {
return NULL;
}
std::unique_ptr<Value, decltype(&FreeValue)> filename(arg_filename, FreeValue);
std::unique_ptr<Value, decltype(&FreeValue)> ranges(arg_ranges, FreeValue);
if (filename->type != VAL_STRING) {
ErrorAbort(state, "filename argument to %s must be string", name);
return StringValue(strdup(""));
}
if (ranges->type != VAL_STRING) {
ErrorAbort(state, "ranges argument to %s must be string", name);
return StringValue(strdup(""));
}
// Output notice to log when recover is attempted
fprintf(stderr, "%s image corrupted, attempting to recover...\n", filename->data);
// When opened with O_RDWR, libfec rewrites corrupted blocks when they are read
fec::io fh(filename->data, O_RDWR);
if (!fh) {
ErrorAbort(state, "fec_open \"%s\" failed: %s", filename->data, strerror(errno));
return StringValue(strdup(""));
}
if (!fh.has_ecc() || !fh.has_verity()) {
ErrorAbort(state, "unable to use metadata to correct errors");
return StringValue(strdup(""));
}
fec_status status;
if (!fh.get_status(status)) {
ErrorAbort(state, "failed to read FEC status");
return StringValue(strdup(""));
}
RangeSet rs;
parse_range(ranges->data, rs);
uint8_t buffer[BLOCKSIZE];
for (size_t i = 0; i < rs.count; ++i) {
for (size_t j = rs.pos[i * 2]; j < rs.pos[i * 2 + 1]; ++j) {
// Stay within the data area, libfec validates and corrects metadata
if (status.data_size <= (uint64_t)j * BLOCKSIZE) {
continue;
}
if (fh.pread(buffer, BLOCKSIZE, (off64_t)j * BLOCKSIZE) != BLOCKSIZE) {
ErrorAbort(state, "failed to recover %s (block %zu): %s", filename->data,
j, strerror(errno));
return StringValue(strdup(""));
}
// If we want to be able to recover from a situation where rewriting a corrected
// block doesn't guarantee the same data will be returned when re-read later, we
// can save a copy of corrected blocks to /cache. Note:
//
// 1. Maximum space required from /cache is the same as the maximum number of
// corrupted blocks we can correct. For RS(255, 253) and a 2 GiB partition,
// this would be ~16 MiB, for example.
//
// 2. To find out if this block was corrupted, call fec_get_status after each
// read and check if the errors field value has increased.
}
}
fprintf(stderr, "...%s image recovered successfully.\n", filename->data);
return StringValue(strdup("t"));
}
void RegisterBlockImageFunctions() {
RegisterFunction("block_image_verify", BlockImageVerifyFn);
RegisterFunction("block_image_update", BlockImageUpdateFn);
RegisterFunction("block_image_recover", BlockImageRecoverFn);
RegisterFunction("check_first_block", CheckFirstBlockFn);
RegisterFunction("range_sha1", RangeSha1Fn);
}
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