937 lines
31 KiB
C
937 lines
31 KiB
C
/*
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* Copyright (C) 2008 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#include <errno.h>
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#include <libgen.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <sys/stat.h>
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#include <sys/statfs.h>
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#include <sys/types.h>
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#include <fcntl.h>
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#include <unistd.h>
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#include "mincrypt/sha.h"
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#include "applypatch.h"
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#include "mtdutils/mtdutils.h"
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#include "edify/expr.h"
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static int LoadPartitionContents(const char* filename, FileContents* file);
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static ssize_t FileSink(unsigned char* data, ssize_t len, void* token);
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static int GenerateTarget(FileContents* source_file,
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const Value* source_patch_value,
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FileContents* copy_file,
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const Value* copy_patch_value,
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const char* source_filename,
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const char* target_filename,
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const uint8_t target_sha1[SHA_DIGEST_SIZE],
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size_t target_size);
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static int mtd_partitions_scanned = 0;
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// Read a file into memory; optionally (retouch_flag == RETOUCH_DO_MASK) mask
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// the retouched entries back to their original value (such that SHA-1 checks
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// don't fail due to randomization); store the file contents and associated
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// metadata in *file.
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//
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// Return 0 on success.
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int LoadFileContents(const char* filename, FileContents* file,
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int retouch_flag) {
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file->data = NULL;
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// A special 'filename' beginning with "MTD:" or "EMMC:" means to
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// load the contents of a partition.
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if (strncmp(filename, "MTD:", 4) == 0 ||
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strncmp(filename, "EMMC:", 5) == 0) {
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return LoadPartitionContents(filename, file);
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}
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if (stat(filename, &file->st) != 0) {
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printf("failed to stat \"%s\": %s\n", filename, strerror(errno));
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return -1;
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}
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file->size = file->st.st_size;
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file->data = malloc(file->size);
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FILE* f = fopen(filename, "rb");
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if (f == NULL) {
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printf("failed to open \"%s\": %s\n", filename, strerror(errno));
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free(file->data);
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file->data = NULL;
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return -1;
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}
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ssize_t bytes_read = fread(file->data, 1, file->size, f);
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if (bytes_read != file->size) {
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printf("short read of \"%s\" (%ld bytes of %ld)\n",
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filename, (long)bytes_read, (long)file->size);
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free(file->data);
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file->data = NULL;
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return -1;
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}
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fclose(f);
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// apply_patch[_check] functions are blind to randomization. Randomization
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// is taken care of in [Undo]RetouchBinariesFn. If there is a mismatch
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// within a file, this means the file is assumed "corrupt" for simplicity.
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if (retouch_flag) {
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int32_t desired_offset = 0;
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if (retouch_mask_data(file->data, file->size,
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&desired_offset, NULL) != RETOUCH_DATA_MATCHED) {
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printf("error trying to mask retouch entries\n");
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free(file->data);
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file->data = NULL;
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return -1;
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}
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}
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SHA(file->data, file->size, file->sha1);
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return 0;
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}
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static size_t* size_array;
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// comparison function for qsort()ing an int array of indexes into
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// size_array[].
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static int compare_size_indices(const void* a, const void* b) {
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int aa = *(int*)a;
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int bb = *(int*)b;
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if (size_array[aa] < size_array[bb]) {
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return -1;
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} else if (size_array[aa] > size_array[bb]) {
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return 1;
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} else {
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return 0;
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}
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}
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// Load the contents of an MTD or EMMC partition into the provided
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// FileContents. filename should be a string of the form
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// "MTD:<partition_name>:<size_1>:<sha1_1>:<size_2>:<sha1_2>:..." (or
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// "EMMC:<partition_device>:..."). The smallest size_n bytes for
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// which that prefix of the partition contents has the corresponding
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// sha1 hash will be loaded. It is acceptable for a size value to be
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// repeated with different sha1s. Will return 0 on success.
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//
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// This complexity is needed because if an OTA installation is
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// interrupted, the partition might contain either the source or the
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// target data, which might be of different lengths. We need to know
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// the length in order to read from a partition (there is no
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// "end-of-file" marker), so the caller must specify the possible
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// lengths and the hash of the data, and we'll do the load expecting
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// to find one of those hashes.
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enum PartitionType { MTD, EMMC };
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static int LoadPartitionContents(const char* filename, FileContents* file) {
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char* copy = strdup(filename);
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const char* magic = strtok(copy, ":");
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enum PartitionType type;
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if (strcmp(magic, "MTD") == 0) {
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type = MTD;
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} else if (strcmp(magic, "EMMC") == 0) {
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type = EMMC;
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} else {
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printf("LoadPartitionContents called with bad filename (%s)\n",
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filename);
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return -1;
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}
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const char* partition = strtok(NULL, ":");
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int i;
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int colons = 0;
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for (i = 0; filename[i] != '\0'; ++i) {
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if (filename[i] == ':') {
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++colons;
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}
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}
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if (colons < 3 || colons%2 == 0) {
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printf("LoadPartitionContents called with bad filename (%s)\n",
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filename);
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}
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int pairs = (colons-1)/2; // # of (size,sha1) pairs in filename
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int* index = malloc(pairs * sizeof(int));
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size_t* size = malloc(pairs * sizeof(size_t));
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char** sha1sum = malloc(pairs * sizeof(char*));
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for (i = 0; i < pairs; ++i) {
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const char* size_str = strtok(NULL, ":");
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size[i] = strtol(size_str, NULL, 10);
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if (size[i] == 0) {
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printf("LoadPartitionContents called with bad size (%s)\n", filename);
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return -1;
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}
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sha1sum[i] = strtok(NULL, ":");
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index[i] = i;
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}
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// sort the index[] array so it indexes the pairs in order of
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// increasing size.
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size_array = size;
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qsort(index, pairs, sizeof(int), compare_size_indices);
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MtdReadContext* ctx = NULL;
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FILE* dev = NULL;
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switch (type) {
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case MTD:
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if (!mtd_partitions_scanned) {
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mtd_scan_partitions();
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mtd_partitions_scanned = 1;
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}
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const MtdPartition* mtd = mtd_find_partition_by_name(partition);
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if (mtd == NULL) {
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printf("mtd partition \"%s\" not found (loading %s)\n",
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partition, filename);
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return -1;
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}
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ctx = mtd_read_partition(mtd);
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if (ctx == NULL) {
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printf("failed to initialize read of mtd partition \"%s\"\n",
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partition);
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return -1;
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}
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break;
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case EMMC:
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dev = fopen(partition, "rb");
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if (dev == NULL) {
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printf("failed to open emmc partition \"%s\": %s\n",
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partition, strerror(errno));
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return -1;
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}
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}
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SHA_CTX sha_ctx;
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SHA_init(&sha_ctx);
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uint8_t parsed_sha[SHA_DIGEST_SIZE];
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// allocate enough memory to hold the largest size.
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file->data = malloc(size[index[pairs-1]]);
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char* p = (char*)file->data;
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file->size = 0; // # bytes read so far
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for (i = 0; i < pairs; ++i) {
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// Read enough additional bytes to get us up to the next size
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// (again, we're trying the possibilities in order of increasing
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// size).
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size_t next = size[index[i]] - file->size;
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size_t read = 0;
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if (next > 0) {
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switch (type) {
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case MTD:
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read = mtd_read_data(ctx, p, next);
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break;
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case EMMC:
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read = fread(p, 1, next, dev);
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break;
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}
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if (next != read) {
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printf("short read (%d bytes of %d) for partition \"%s\"\n",
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read, next, partition);
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free(file->data);
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file->data = NULL;
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return -1;
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}
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SHA_update(&sha_ctx, p, read);
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file->size += read;
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}
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// Duplicate the SHA context and finalize the duplicate so we can
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// check it against this pair's expected hash.
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SHA_CTX temp_ctx;
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memcpy(&temp_ctx, &sha_ctx, sizeof(SHA_CTX));
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const uint8_t* sha_so_far = SHA_final(&temp_ctx);
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if (ParseSha1(sha1sum[index[i]], parsed_sha) != 0) {
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printf("failed to parse sha1 %s in %s\n",
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sha1sum[index[i]], filename);
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free(file->data);
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file->data = NULL;
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return -1;
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}
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if (memcmp(sha_so_far, parsed_sha, SHA_DIGEST_SIZE) == 0) {
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// we have a match. stop reading the partition; we'll return
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// the data we've read so far.
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printf("partition read matched size %d sha %s\n",
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size[index[i]], sha1sum[index[i]]);
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break;
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}
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p += read;
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}
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switch (type) {
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case MTD:
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mtd_read_close(ctx);
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break;
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case EMMC:
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fclose(dev);
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break;
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}
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if (i == pairs) {
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// Ran off the end of the list of (size,sha1) pairs without
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// finding a match.
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printf("contents of partition \"%s\" didn't match %s\n",
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partition, filename);
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free(file->data);
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file->data = NULL;
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return -1;
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}
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const uint8_t* sha_final = SHA_final(&sha_ctx);
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for (i = 0; i < SHA_DIGEST_SIZE; ++i) {
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file->sha1[i] = sha_final[i];
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}
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// Fake some stat() info.
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file->st.st_mode = 0644;
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file->st.st_uid = 0;
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file->st.st_gid = 0;
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free(copy);
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free(index);
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free(size);
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free(sha1sum);
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return 0;
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}
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// Save the contents of the given FileContents object under the given
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// filename. Return 0 on success.
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int SaveFileContents(const char* filename, const FileContents* file) {
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int fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC);
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if (fd < 0) {
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printf("failed to open \"%s\" for write: %s\n",
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filename, strerror(errno));
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return -1;
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}
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ssize_t bytes_written = FileSink(file->data, file->size, &fd);
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if (bytes_written != file->size) {
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printf("short write of \"%s\" (%ld bytes of %ld) (%s)\n",
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filename, (long)bytes_written, (long)file->size,
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strerror(errno));
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close(fd);
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return -1;
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}
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fsync(fd);
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close(fd);
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if (chmod(filename, file->st.st_mode) != 0) {
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printf("chmod of \"%s\" failed: %s\n", filename, strerror(errno));
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return -1;
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}
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if (chown(filename, file->st.st_uid, file->st.st_gid) != 0) {
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printf("chown of \"%s\" failed: %s\n", filename, strerror(errno));
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return -1;
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}
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return 0;
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}
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// Write a memory buffer to 'target' partition, a string of the form
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// "MTD:<partition>[:...]" or "EMMC:<partition_device>:". Return 0 on
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// success.
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int WriteToPartition(unsigned char* data, size_t len,
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const char* target) {
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char* copy = strdup(target);
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const char* magic = strtok(copy, ":");
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enum PartitionType type;
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if (strcmp(magic, "MTD") == 0) {
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type = MTD;
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} else if (strcmp(magic, "EMMC") == 0) {
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type = EMMC;
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} else {
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printf("WriteToPartition called with bad target (%s)\n", target);
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return -1;
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}
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const char* partition = strtok(NULL, ":");
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if (partition == NULL) {
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printf("bad partition target name \"%s\"\n", target);
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return -1;
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}
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switch (type) {
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case MTD:
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if (!mtd_partitions_scanned) {
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mtd_scan_partitions();
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mtd_partitions_scanned = 1;
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}
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const MtdPartition* mtd = mtd_find_partition_by_name(partition);
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if (mtd == NULL) {
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printf("mtd partition \"%s\" not found for writing\n",
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partition);
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return -1;
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}
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MtdWriteContext* ctx = mtd_write_partition(mtd);
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if (ctx == NULL) {
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printf("failed to init mtd partition \"%s\" for writing\n",
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partition);
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return -1;
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}
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size_t written = mtd_write_data(ctx, (char*)data, len);
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if (written != len) {
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printf("only wrote %d of %d bytes to MTD %s\n",
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written, len, partition);
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mtd_write_close(ctx);
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return -1;
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}
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if (mtd_erase_blocks(ctx, -1) < 0) {
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printf("error finishing mtd write of %s\n", partition);
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mtd_write_close(ctx);
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return -1;
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}
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if (mtd_write_close(ctx)) {
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printf("error closing mtd write of %s\n", partition);
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return -1;
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}
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break;
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case EMMC:
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;
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FILE* f = fopen(partition, "wb");
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if (fwrite(data, 1, len, f) != len) {
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printf("short write writing to %s (%s)\n",
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partition, strerror(errno));
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return -1;
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}
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if (fclose(f) != 0) {
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printf("error closing %s (%s)\n", partition, strerror(errno));
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return -1;
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}
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break;
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}
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free(copy);
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return 0;
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}
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// Take a string 'str' of 40 hex digits and parse it into the 20
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// byte array 'digest'. 'str' may contain only the digest or be of
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// the form "<digest>:<anything>". Return 0 on success, -1 on any
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// error.
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int ParseSha1(const char* str, uint8_t* digest) {
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int i;
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const char* ps = str;
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uint8_t* pd = digest;
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for (i = 0; i < SHA_DIGEST_SIZE * 2; ++i, ++ps) {
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int digit;
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if (*ps >= '0' && *ps <= '9') {
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digit = *ps - '0';
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} else if (*ps >= 'a' && *ps <= 'f') {
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digit = *ps - 'a' + 10;
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} else if (*ps >= 'A' && *ps <= 'F') {
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digit = *ps - 'A' + 10;
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} else {
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return -1;
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}
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if (i % 2 == 0) {
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*pd = digit << 4;
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} else {
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*pd |= digit;
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++pd;
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}
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}
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if (*ps != '\0') return -1;
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return 0;
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}
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// Search an array of sha1 strings for one matching the given sha1.
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// Return the index of the match on success, or -1 if no match is
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// found.
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int FindMatchingPatch(uint8_t* sha1, const char** patch_sha1_str,
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int num_patches) {
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int i;
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uint8_t patch_sha1[SHA_DIGEST_SIZE];
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for (i = 0; i < num_patches; ++i) {
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if (ParseSha1(patch_sha1_str[i], patch_sha1) == 0 &&
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memcmp(patch_sha1, sha1, SHA_DIGEST_SIZE) == 0) {
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return i;
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}
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}
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return -1;
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}
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// Returns 0 if the contents of the file (argv[2]) or the cached file
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// match any of the sha1's on the command line (argv[3:]). Returns
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// nonzero otherwise.
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int applypatch_check(const char* filename,
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int num_patches, char** const patch_sha1_str) {
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FileContents file;
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file.data = NULL;
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// It's okay to specify no sha1s; the check will pass if the
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// LoadFileContents is successful. (Useful for reading
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// partitions, where the filename encodes the sha1s; no need to
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// check them twice.)
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if (LoadFileContents(filename, &file, RETOUCH_DO_MASK) != 0 ||
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(num_patches > 0 &&
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FindMatchingPatch(file.sha1, patch_sha1_str, num_patches) < 0)) {
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printf("file \"%s\" doesn't have any of expected "
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"sha1 sums; checking cache\n", filename);
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free(file.data);
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file.data = NULL;
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// If the source file is missing or corrupted, it might be because
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// we were killed in the middle of patching it. A copy of it
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// should have been made in CACHE_TEMP_SOURCE. If that file
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// exists and matches the sha1 we're looking for, the check still
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// passes.
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if (LoadFileContents(CACHE_TEMP_SOURCE, &file, RETOUCH_DO_MASK) != 0) {
|
|
printf("failed to load cache file\n");
|
|
return 1;
|
|
}
|
|
|
|
if (FindMatchingPatch(file.sha1, patch_sha1_str, num_patches) < 0) {
|
|
printf("cache bits don't match any sha1 for \"%s\"\n", filename);
|
|
free(file.data);
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
free(file.data);
|
|
return 0;
|
|
}
|
|
|
|
int ShowLicenses() {
|
|
ShowBSDiffLicense();
|
|
return 0;
|
|
}
|
|
|
|
ssize_t FileSink(unsigned char* data, ssize_t len, void* token) {
|
|
int fd = *(int *)token;
|
|
ssize_t done = 0;
|
|
ssize_t wrote;
|
|
while (done < (ssize_t) len) {
|
|
wrote = write(fd, data+done, len-done);
|
|
if (wrote <= 0) {
|
|
printf("error writing %d bytes: %s\n", (int)(len-done), strerror(errno));
|
|
return done;
|
|
}
|
|
done += wrote;
|
|
}
|
|
return done;
|
|
}
|
|
|
|
typedef struct {
|
|
unsigned char* buffer;
|
|
ssize_t size;
|
|
ssize_t pos;
|
|
} MemorySinkInfo;
|
|
|
|
ssize_t MemorySink(unsigned char* data, ssize_t len, void* token) {
|
|
MemorySinkInfo* msi = (MemorySinkInfo*)token;
|
|
if (msi->size - msi->pos < len) {
|
|
return -1;
|
|
}
|
|
memcpy(msi->buffer + msi->pos, data, len);
|
|
msi->pos += len;
|
|
return len;
|
|
}
|
|
|
|
// Return the amount of free space (in bytes) on the filesystem
|
|
// containing filename. filename must exist. Return -1 on error.
|
|
size_t FreeSpaceForFile(const char* filename) {
|
|
struct statfs sf;
|
|
if (statfs(filename, &sf) != 0) {
|
|
printf("failed to statfs %s: %s\n", filename, strerror(errno));
|
|
return -1;
|
|
}
|
|
return sf.f_bsize * sf.f_bfree;
|
|
}
|
|
|
|
int CacheSizeCheck(size_t bytes) {
|
|
if (MakeFreeSpaceOnCache(bytes) < 0) {
|
|
printf("unable to make %ld bytes available on /cache\n", (long)bytes);
|
|
return 1;
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
|
|
// This function applies binary patches to files in a way that is safe
|
|
// (the original file is not touched until we have the desired
|
|
// replacement for it) and idempotent (it's okay to run this program
|
|
// multiple times).
|
|
//
|
|
// - if the sha1 hash of <target_filename> is <target_sha1_string>,
|
|
// does nothing and exits successfully.
|
|
//
|
|
// - otherwise, if the sha1 hash of <source_filename> is one of the
|
|
// entries in <patch_sha1_str>, the corresponding patch from
|
|
// <patch_data> (which must be a VAL_BLOB) is applied to produce a
|
|
// new file (the type of patch is automatically detected from the
|
|
// blob daat). If that new file has sha1 hash <target_sha1_str>,
|
|
// moves it to replace <target_filename>, and exits successfully.
|
|
// Note that if <source_filename> and <target_filename> are not the
|
|
// same, <source_filename> is NOT deleted on success.
|
|
// <target_filename> may be the string "-" to mean "the same as
|
|
// source_filename".
|
|
//
|
|
// - otherwise, or if any error is encountered, exits with non-zero
|
|
// status.
|
|
//
|
|
// <source_filename> may refer to a partition to read the source data.
|
|
// See the comments for the LoadPartition Contents() function above
|
|
// for the format of such a filename.
|
|
|
|
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;
|
|
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,
|
|
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);
|
|
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,
|
|
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);
|
|
source_file.data = NULL;
|
|
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");
|
|
free(copy_file.data);
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
int result = GenerateTarget(&source_file, source_patch_value,
|
|
©_file, copy_patch_value,
|
|
source_filename, target_filename,
|
|
target_sha1, target_size);
|
|
free(source_file.data);
|
|
free(copy_file.data);
|
|
|
|
return result;
|
|
}
|
|
|
|
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) {
|
|
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
|
|
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, "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 %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 = 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 = 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);
|
|
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;
|
|
}
|