/*
* This function flashes a given image to the target partition. It verifies
* the target cheksum first, and will return if target has the desired hash.
* It checks the checksum of the given source image before flashing, and
* verifies the target partition afterwards. The function is idempotent.
* Returns zero on success.
*/
int applypatch_flash(const char* source_filename, const char* target_filename,
const char* target_sha1_str, size_t target_size) {
printf("flash %s: ", target_filename);
uint8_t target_sha1[SHA_DIGEST_SIZE];
if (ParseSha1(target_sha1_str, target_sha1) != 0) {
printf("failed to parse tgt-sha1 \"%s\"\n", target_sha1_str);
return 1;
}
FileContents source_file;
source_file.data = NULL;
std::string target_str(target_filename);
std::vector<std::string> pieces = android::base::Split(target_str, ":");
if (pieces.size() != 2 || (pieces[0] != "MTD" && pieces[0] != "EMMC")) {
printf("invalid target name \"%s\"", target_filename);
return 1;
}
// Load the target into the source_file object to see if already applied.
pieces.push_back(std::to_string(target_size));
pieces.push_back(target_sha1_str);
std::string fullname = android::base::Join(pieces, ':');
if (LoadPartitionContents(fullname.c_str(), &source_file) == 0 &&
memcmp(source_file.sha1, target_sha1, SHA_DIGEST_SIZE) == 0) {
// The early-exit case: the image was already applied, this partition
// has the desired hash, nothing for us to do.
printf("already %s\n", short_sha1(target_sha1).c_str());
free(source_file.data);
return 0;
}
if (LoadFileContents(source_filename, &source_file) == 0) {
if (memcmp(source_file.sha1, target_sha1, SHA_DIGEST_SIZE) != 0) {
// The source doesn't have desired checksum.
printf("source \"%s\" doesn't have expected sha1 sum\n", source_filename);
printf("expected: %s, found: %s\n", short_sha1(target_sha1).c_str(),
short_sha1(source_file.sha1).c_str());
free(source_file.data);
return 1;
}
}
if (WriteToPartition(source_file.data, target_size, target_filename) != 0) {
printf("write of copied data to %s failed\n", target_filename);
free(source_file.data);
return 1;
}
free(source_file.data);
return 0;
}
int applypatch(const char* source_filename,
const char* target_filename,
const char* target_sha1_str,
size_t target_size,
int num_patches,
char** const patch_sha1_str,
Value** patch_data) {
printf("\napplying patch to %s\n", source_filename);
if (target_filename[0] == '-' &&
target_filename[1] == '\0') {
target_filename = source_filename;
}
uint8_t target_sha1[SHA_DIGEST_SIZE];
if (ParseSha1(target_sha1_str, target_sha1) != 0) {
printf("failed to parse tgt-sha1 \"%s\"\n", target_sha1_str);
return 1;
}
FileContents copy_file;
FileContents source_file;
const Value* source_patch_value = NULL;
const Value* copy_patch_value = NULL;
int made_copy = 0;
// We try to load the target file into the source_file object.
if (LoadFileContents(target_filename, &source_file,
RETOUCH_DO_MASK) == 0) {
if (memcmp(source_file.sha1, target_sha1, SHA_DIGEST_SIZE) == 0) {
// The early-exit case: the patch was already applied, this file
// has the desired hash, nothing for us to do.
printf("\"%s\" is already target; no patch needed\n",
target_filename);
return 0;
}
}
if (source_file.data == NULL ||
(target_filename != source_filename &&
strcmp(target_filename, source_filename) != 0)) {
// Need to load the source file: either we failed to load the
// target file, or we did but it's different from the source file.
free(source_file.data);
LoadFileContents(source_filename, &source_file,
RETOUCH_DO_MASK);
}
if (source_file.data != NULL) {
int to_use = FindMatchingPatch(source_file.sha1,
patch_sha1_str, num_patches);
if (to_use >= 0) {
source_patch_value = patch_data[to_use];
}
}
if (source_patch_value == NULL) {
free(source_file.data);
printf("source file is bad; trying copy\n");
if (LoadFileContents(CACHE_TEMP_SOURCE, ©_file,
RETOUCH_DO_MASK) < 0) {
// fail.
printf("failed to read copy file\n");
return 1;
}
int to_use = FindMatchingPatch(copy_file.sha1,
patch_sha1_str, num_patches);
if (to_use >= 0) {
copy_patch_value = patch_data[to_use];
}
if (copy_patch_value == NULL) {
// fail.
printf("copy file doesn't match source SHA-1s either\n");
return 1;
}
}
int retry = 1;
SHA_CTX ctx;
int output;
MemorySinkInfo msi;
FileContents* source_to_use;
char* outname;
// assume that target_filename (eg "/system/app/Foo.apk") is located
// on the same filesystem as its top-level directory ("/system").
// We need something that exists for calling statfs().
char target_fs[strlen(target_filename)+1];
char* slash = strchr(target_filename+1, '/');
if (slash != NULL) {
int count = slash - target_filename;
strncpy(target_fs, target_filename, count);
target_fs[count] = '\0';
} else {
strcpy(target_fs, target_filename);
}
do {
// Is there enough room in the target filesystem to hold the patched
// file?
if (strncmp(target_filename, "EMMC:", 5) == 0) {
// If the target is a partition, we're actually going to
// write the output to /tmp and then copy it to the
// partition. statfs() always returns 0 blocks free for
// /tmp, so instead we'll just assume that /tmp has enough
// space to hold the file.
// We still write the original source to cache, in case
// the partition write is interrupted.
if (MakeFreeSpaceOnCache(source_file.size) < 0) {
printf("not enough free space on /cache\n");
return 1;
}
if (SaveFileContents(CACHE_TEMP_SOURCE, source_file) < 0) {
printf("failed to back up source file\n");
return 1;
}
made_copy = 1;
retry = 0;
} else {
int enough_space = 0;
if (retry > 0) {
size_t free_space = FreeSpaceForFile(target_fs);
enough_space =
(free_space > (256 << 10)) && // 256k (two-block) minimum
(free_space > (target_size * 3 / 2)); // 50% margin of error
printf("target %ld bytes; free space %ld bytes; retry %d; enough %d\n",
(long)target_size, (long)free_space, retry, enough_space);
}
if (!enough_space) {
retry = 0;
}
if (!enough_space && source_patch_value != NULL) {
// Using the original source, but not enough free space. First
// copy the source file to cache, then delete it from the original
// location.
if (strncmp(source_filename, "EMMC:", 5) == 0) {
// It's impossible to free space on the target filesystem by
// deleting the source if the source is a partition. If
// we're ever in a state where we need to do this, fail.
printf("not enough free space for target but source "
"is partition\n");
return 1;
}
if (MakeFreeSpaceOnCache(source_file.size) < 0) {
printf("not enough free space on /cache\n");
return 1;
}
if (SaveFileContents(CACHE_TEMP_SOURCE, source_file) < 0) {
printf("failed to back up source file\n");
return 1;
}
made_copy = 1;
unlink(source_filename);
size_t free_space = FreeSpaceForFile(target_fs);
printf("(now %ld bytes free for target)\n", (long)free_space);
}
}
const Value* patch;
if (source_patch_value != NULL) {
source_to_use = &source_file;
patch = source_patch_value;
} else {
source_to_use = ©_file;
patch = copy_patch_value;
}
if (patch->type != VAL_BLOB) {
printf("patch is not a blob\n");
return 1;
}
SinkFn sink = NULL;
void* token = NULL;
output = -1;
outname = NULL;
if (strncmp(target_filename, "EMMC:", 5) == 0) {
// We store the decoded output in memory.
msi.buffer = malloc(target_size);
if (msi.buffer == NULL) {
printf("failed to alloc %ld bytes for output\n",
(long)target_size);
return 1;
}
msi.pos = 0;
msi.size = target_size;
sink = MemorySink;
token = &msi;
} else {
// We write the decoded output to "<tgt-file>.patch".
outname = (char*)malloc(strlen(target_filename) + 10);
strcpy(outname, target_filename);
strcat(outname, ".patch");
output = open(outname, O_WRONLY | O_CREAT | O_TRUNC | O_SYNC,
S_IRUSR | S_IWUSR);
if (output < 0) {
printf("failed to open output file %s: %s\n",
outname, strerror(errno));
return 1;
}
sink = FileSink;
token = &output;
}
char* header = patch->data;
ssize_t header_bytes_read = patch->size;
SHA_init(&ctx);
int result;
if (header_bytes_read >= 8 &&
memcmp(header, "BSDIFF40", 8) == 0) {
result = ApplyBSDiffPatch(source_to_use->data, source_to_use->size,
patch, 0, sink, token, &ctx);
} else if (header_bytes_read >= 8 &&
memcmp(header, "IMGDIFF2", 8) == 0) {
result = ApplyImagePatch(source_to_use->data, source_to_use->size,
patch, sink, token, &ctx);
} else {
printf("Unknown patch file format\n");
return 1;
}
if (output >= 0) {
fsync(output);
close(output);
}
if (result != 0) {
if (retry == 0) {
printf("applying patch failed\n");
return result != 0;
} else {
printf("applying patch failed; retrying\n");
}
if (outname != NULL) {
unlink(outname);
}
} else {
// succeeded; no need to retry
break;
}
} while (retry-- > 0);
const uint8_t* current_target_sha1 = SHA_final(&ctx);
if (memcmp(current_target_sha1, target_sha1, SHA_DIGEST_SIZE) != 0) {
printf("patch did not produce expected sha1\n");
return 1;
}
if (output < 0) {
// Copy the temp file to the partition.
if (WriteToPartition(msi.buffer, msi.pos, target_filename) != 0) {
printf("write of patched data to %s failed\n", target_filename);
return 1;
}
free(msi.buffer);
} else {
// Give the .patch file the same owner, group, and mode of the
// original source file.
if (chmod(outname, source_to_use->st.st_mode) != 0) {
printf("chmod of \"%s\" failed: %s\n", outname, strerror(errno));
return 1;
}
if (chown(outname, source_to_use->st.st_uid,
source_to_use->st.st_gid) != 0) {
printf("chown of \"%s\" failed: %s\n", outname, strerror(errno));
return 1;
}
// Finally, rename the .patch file to replace the target file.
if (rename(outname, target_filename) != 0) {
printf("rename of .patch to \"%s\" failed: %s\n",
target_filename, strerror(errno));
return 1;
}
}
// If this run of applypatch created the copy, and we're here, we
// can delete it.
if (made_copy) unlink(CACHE_TEMP_SOURCE);
// Success!
return 0;
}
static int GenerateTarget(FileContents* source_file,
const Value* source_patch_value,
FileContents* copy_file,
const Value* copy_patch_value,
const char* source_filename,
const char* target_filename,
const uint8_t target_sha1[SHA_DIGEST_SIZE],
size_t target_size,
const Value* bonus_data) {
int retry = 1;
SHA_CTX ctx;
int output;
MemorySinkInfo msi;
FileContents* source_to_use;
char* outname;
int made_copy = 0;
// assume that target_filename (eg "/system/app/Foo.apk") is located
// on the same filesystem as its top-level directory ("/system").
// We need something that exists for calling statfs().
char target_fs[strlen(target_filename)+1];
char* slash = strchr(target_filename+1, '/');
if (slash != NULL) {
int count = slash - target_filename;
strncpy(target_fs, target_filename, count);
target_fs[count] = '\0';
} else {
strcpy(target_fs, target_filename);
}
do {
// Is there enough room in the target filesystem to hold the patched
// file?
if (strncmp(target_filename, "MTD:", 4) == 0 ||
strncmp(target_filename, "EMMC:", 5) == 0) {
// If the target is a partition, we're actually going to
// write the output to /tmp and then copy it to the
// partition. statfs() always returns 0 blocks free for
// /tmp, so instead we'll just assume that /tmp has enough
// space to hold the file.
// We still write the original source to cache, in case
// the partition write is interrupted.
if (MakeFreeSpaceOnCache(source_file->size) < 0) {
printf("not enough free space on /cache\n");
return 1;
}
if (SaveFileContents(CACHE_TEMP_SOURCE, source_file) < 0) {
printf("failed to back up source file\n");
return 1;
}
made_copy = 1;
retry = 0;
} else {
int enough_space = 0;
if (retry > 0) {
size_t free_space = FreeSpaceForFile(target_fs);
enough_space =
(free_space > (256 << 10)) && // 256k (two-block) minimum
(free_space > (target_size * 3 / 2)); // 50% margin of error
if (!enough_space) {
printf("target %zu bytes; free space %zu bytes; retry %d; enough %d\n",
target_size, free_space, retry, enough_space);
}
}
if (!enough_space) {
retry = 0;
}
if (!enough_space && source_patch_value != NULL) {
// Using the original source, but not enough free space. First
// copy the source file to cache, then delete it from the original
// location.
if (strncmp(source_filename, "MTD:", 4) == 0 ||
strncmp(source_filename, "EMMC:", 5) == 0) {
// It's impossible to free space on the target filesystem by
// deleting the source if the source is a partition. If
// we're ever in a state where we need to do this, fail.
printf("not enough free space for target but source is partition\n");
return 1;
}
if (MakeFreeSpaceOnCache(source_file->size) < 0) {
printf("not enough free space on /cache\n");
return 1;
}
if (SaveFileContents(CACHE_TEMP_SOURCE, source_file) < 0) {
printf("failed to back up source file\n");
return 1;
}
made_copy = 1;
unlink(source_filename);
size_t free_space = FreeSpaceForFile(target_fs);
printf("(now %zu bytes free for target) ", free_space);
}
}
const Value* patch;
if (source_patch_value != NULL) {
source_to_use = source_file;
patch = source_patch_value;
} else {
source_to_use = copy_file;
patch = copy_patch_value;
}
if (patch->type != VAL_BLOB) {
printf("patch is not a blob\n");
return 1;
}
SinkFn sink = NULL;
void* token = NULL;
output = -1;
outname = NULL;
if (strncmp(target_filename, "MTD:", 4) == 0 ||
strncmp(target_filename, "EMMC:", 5) == 0) {
// We store the decoded output in memory.
msi.buffer = reinterpret_cast<unsigned char*>(malloc(target_size));
if (msi.buffer == NULL) {
printf("failed to alloc %zu bytes for output\n", target_size);
return 1;
}
msi.pos = 0;
msi.size = target_size;
sink = MemorySink;
token = &msi;
} else {
// We write the decoded output to "<tgt-file>.patch".
outname = reinterpret_cast<char*>(malloc(strlen(target_filename) + 10));
strcpy(outname, target_filename);
strcat(outname, ".patch");
output = open(outname, O_WRONLY | O_CREAT | O_TRUNC | O_SYNC, S_IRUSR | S_IWUSR);
if (output < 0) {
printf("failed to open output file %s: %s\n",
outname, strerror(errno));
return 1;
}
sink = FileSink;
token = &output;
}
char* header = patch->data;
ssize_t header_bytes_read = patch->size;
SHA_init(&ctx);
int result;
if (header_bytes_read >= 8 &&
memcmp(header, "BSDIFF40", 8) == 0) {
result = ApplyBSDiffPatch(source_to_use->data, source_to_use->size,
patch, 0, sink, token, &ctx);
} else if (header_bytes_read >= 8 &&
memcmp(header, "IMGDIFF2", 8) == 0) {
result = ApplyImagePatch(source_to_use->data, source_to_use->size,
patch, sink, token, &ctx, bonus_data);
} else {
printf("Unknown patch file format\n");
return 1;
}
if (output >= 0) {
if (fsync(output) != 0) {
printf("failed to fsync file \"%s\" (%s)\n", outname, strerror(errno));
result = 1;
}
if (close(output) != 0) {
printf("failed to close file \"%s\" (%s)\n", outname, strerror(errno));
result = 1;
}
}
if (result != 0) {
if (retry == 0) {
printf("applying patch failed\n");
return result != 0;
} else {
printf("applying patch failed; retrying\n");
}
if (outname != NULL) {
unlink(outname);
}
} else {
// succeeded; no need to retry
break;
}
} while (retry-- > 0);
const uint8_t* current_target_sha1 = SHA_final(&ctx);
if (memcmp(current_target_sha1, target_sha1, SHA_DIGEST_SIZE) != 0) {
printf("patch did not produce expected sha1\n");
return 1;
} else {
printf("now %s\n", short_sha1(target_sha1).c_str());
}
if (output < 0) {
// Copy the temp file to the partition.
if (WriteToPartition(msi.buffer, msi.pos, target_filename) != 0) {
printf("write of patched data to %s failed\n", target_filename);
return 1;
}
free(msi.buffer);
} else {
// Give the .patch file the same owner, group, and mode of the
// original source file.
if (chmod(outname, source_to_use->st.st_mode) != 0) {
printf("chmod of \"%s\" failed: %s\n", outname, strerror(errno));
return 1;
}
if (chown(outname, source_to_use->st.st_uid, source_to_use->st.st_gid) != 0) {
printf("chown of \"%s\" failed: %s\n", outname, strerror(errno));
return 1;
}
// Finally, rename the .patch file to replace the target file.
if (rename(outname, target_filename) != 0) {
printf("rename of .patch to \"%s\" failed: %s\n", target_filename, strerror(errno));
return 1;
}
}
// If this run of applypatch created the copy, and we're here, we
// can delete it.
if (made_copy) {
unlink(CACHE_TEMP_SOURCE);
}
// Success!
return 0;
}
int applypatch(const char* source_filename,
const char* target_filename,
const char* target_sha1_str,
size_t target_size,
int num_patches,
char** const patch_sha1_str,
Value** patch_data,
Value* bonus_data) {
printf("patch %s: ", source_filename);
if (target_filename[0] == '-' &&
target_filename[1] == '\0') {
target_filename = source_filename;
}
uint8_t target_sha1[SHA_DIGEST_SIZE];
if (ParseSha1(target_sha1_str, target_sha1) != 0) {
printf("failed to parse tgt-sha1 \"%s\"\n", target_sha1_str);
return 1;
}
FileContents copy_file;
FileContents source_file;
copy_file.data = NULL;
source_file.data = NULL;
const Value* source_patch_value = NULL;
const Value* copy_patch_value = NULL;
// We try to load the target file into the source_file object.
if (LoadFileContents(target_filename, &source_file) == 0) {
if (memcmp(source_file.sha1, target_sha1, SHA_DIGEST_SIZE) == 0) {
// The early-exit case: the patch was already applied, this file
// has the desired hash, nothing for us to do.
printf("already ");
print_short_sha1(target_sha1);
putchar('\n');
free(source_file.data);
return 0;
}
}
if (source_file.data == NULL ||
(target_filename != source_filename &&
strcmp(target_filename, source_filename) != 0)) {
// Need to load the source file: either we failed to load the
// target file, or we did but it's different from the source file.
free(source_file.data);
source_file.data = NULL;
LoadFileContents(source_filename, &source_file);
}
if (source_file.data != NULL) {
int to_use = FindMatchingPatch(source_file.sha1,
patch_sha1_str, num_patches);
if (to_use >= 0) {
source_patch_value = patch_data[to_use];
}
}
if (source_patch_value == NULL) {
free(source_file.data);
source_file.data = NULL;
printf("source file is bad; trying copy\n");
if (LoadFileContents(CACHE_TEMP_SOURCE, ©_file) < 0) {
// fail.
printf("failed to read copy file\n");
return 1;
}
int to_use = FindMatchingPatch(copy_file.sha1,
patch_sha1_str, num_patches);
if (to_use >= 0) {
copy_patch_value = patch_data[to_use];
}
if (copy_patch_value == NULL) {
// fail.
printf("copy file doesn't match source SHA-1s either\n");
#if 0 //wschen 2013-05-23
free(copy_file.data);
return 1;
#else
if (memcmp(copy_file.sha1, target_sha1, SHA_DIGEST_SIZE) == 0) {
printf("use cache temp file to replace \"%s\"\n", target_filename);
if (strncmp(target_filename, "MTD:", 4) == 0 || strncmp(target_filename, "EMMC:", 5) == 0) {
if (WriteToPartition(copy_file.data, copy_file.size, target_filename) != 0) {
printf("write of patched data to %s failed\n", target_filename);
return 1;
}
//everything is fine
unlink(CACHE_TEMP_SOURCE);
sync();
return 0;
} else {
if (SaveFileContents(target_filename, ©_file) < 0) {
printf("failed to copy back %s\n", target_filename);
free(copy_file.data);
copy_file.data = NULL;
return 1;
} else {
//copy success
free(copy_file.data);
copy_file.data = NULL;
if (LoadFileContents(target_filename, &source_file) == 0) {
if (memcmp(source_file.sha1, target_sha1, SHA_DIGEST_SIZE) == 0) {
free(source_file.data);
source_file.data = NULL;
//everything is fine
unlink(CACHE_TEMP_SOURCE);
sync();
return 0;
} else {
free(source_file.data);
source_file.data = NULL;
printf("copied target file (%s) SHA1 does not match\n", target_filename);
return 1;
}
} else {
printf("failed to read copied target file (%s)\n", target_filename);
return 1;
}
}
}
} else {
printf("cache temp file doesn't match target SHA-1s (%s)\n", target_filename);
free(copy_file.data);
copy_file.data = NULL;
return 1;
}
#endif
}
}
int result = GenerateTarget(&source_file, source_patch_value,
©_file, copy_patch_value,
source_filename, target_filename,
target_sha1, target_size, bonus_data);
free(source_file.data);
free(copy_file.data);
return result;
}
