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-rw-r--r--tools/applypatch/applypatch.c457
1 files changed, 0 insertions, 457 deletions
diff --git a/tools/applypatch/applypatch.c b/tools/applypatch/applypatch.c
deleted file mode 100644
index 9954869..0000000
--- a/tools/applypatch/applypatch.c
+++ /dev/null
@@ -1,457 +0,0 @@
-/*
- * Copyright (C) 2008 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 <errno.h>
-#include <libgen.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/stat.h>
-#include <sys/statfs.h>
-#include <unistd.h>
-
-#include "mincrypt/sha.h"
-#include "applypatch.h"
-
-// Read a file into memory; store it and its associated metadata in
-// *file. Return 0 on success.
-int LoadFileContents(const char* filename, FileContents* file) {
- file->data = NULL;
-
- if (stat(filename, &file->st) != 0) {
- fprintf(stderr, "failed to stat \"%s\": %s\n", filename, strerror(errno));
- return -1;
- }
-
- file->size = file->st.st_size;
- file->data = malloc(file->size);
-
- FILE* f = fopen(filename, "rb");
- if (f == NULL) {
- fprintf(stderr, "failed to open \"%s\": %s\n", filename, strerror(errno));
- free(file->data);
- return -1;
- }
-
- size_t bytes_read = fread(file->data, 1, file->size, f);
- if (bytes_read != file->size) {
- fprintf(stderr, "short read of \"%s\" (%d bytes of %d)\n",
- filename, bytes_read, file->size);
- free(file->data);
- return -1;
- }
- fclose(f);
-
- SHA(file->data, file->size, file->sha1);
- return 0;
-}
-
-// Save the contents of the given FileContents object under the given
-// filename. Return 0 on success.
-int SaveFileContents(const char* filename, FileContents file) {
- FILE* f = fopen(filename, "wb");
- if (f == NULL) {
- fprintf(stderr, "failed to open \"%s\" for write: %s\n",
- filename, strerror(errno));
- return -1;
- }
-
- size_t bytes_written = fwrite(file.data, 1, file.size, f);
- if (bytes_written != file.size) {
- fprintf(stderr, "short write of \"%s\" (%d bytes of %d)\n",
- filename, bytes_written, file.size);
- return -1;
- }
- fflush(f);
- fsync(fileno(f));
- fclose(f);
-
- if (chmod(filename, file.st.st_mode) != 0) {
- fprintf(stderr, "chmod of \"%s\" failed: %s\n", filename, strerror(errno));
- return -1;
- }
- if (chown(filename, file.st.st_uid, file.st.st_gid) != 0) {
- fprintf(stderr, "chown of \"%s\" failed: %s\n", filename, strerror(errno));
- return -1;
- }
-
- return 0;
-}
-
-
-// Take a string 'str' of 40 hex digits and parse it into the 20
-// byte array 'digest'. 'str' may contain only the digest or be of
-// the form "<digest>:<anything>". Return 0 on success, -1 on any
-// error.
-int ParseSha1(const char* str, uint8_t* digest) {
- int i;
- const char* ps = str;
- uint8_t* pd = digest;
- for (i = 0; i < SHA_DIGEST_SIZE * 2; ++i, ++ps) {
- int digit;
- if (*ps >= '0' && *ps <= '9') {
- digit = *ps - '0';
- } else if (*ps >= 'a' && *ps <= 'f') {
- digit = *ps - 'a' + 10;
- } else if (*ps >= 'A' && *ps <= 'F') {
- digit = *ps - 'A' + 10;
- } else {
- return -1;
- }
- if (i % 2 == 0) {
- *pd = digit << 4;
- } else {
- *pd |= digit;
- ++pd;
- }
- }
- if (*ps != '\0' && *ps != ':') return -1;
- return 0;
-}
-
-// Parse arguments (which should be of the form "<sha1>" or
-// "<sha1>:<filename>" into the array *patches, returning the number
-// of Patch objects in *num_patches. Return 0 on success.
-int ParseShaArgs(int argc, char** argv, Patch** patches, int* num_patches) {
- *num_patches = argc;
- *patches = malloc(*num_patches * sizeof(Patch));
-
- int i;
- for (i = 0; i < *num_patches; ++i) {
- if (ParseSha1(argv[i], (*patches)[i].sha1) != 0) {
- fprintf(stderr, "failed to parse sha1 \"%s\"\n", argv[i]);
- return -1;
- }
- if (argv[i][SHA_DIGEST_SIZE*2] == '\0') {
- (*patches)[i].patch_filename = NULL;
- } else if (argv[i][SHA_DIGEST_SIZE*2] == ':') {
- (*patches)[i].patch_filename = argv[i] + (SHA_DIGEST_SIZE*2+1);
- } else {
- fprintf(stderr, "failed to parse filename \"%s\"\n", argv[i]);
- return -1;
- }
- }
-
- return 0;
-}
-
-// Search an array of Patch objects for one matching the given sha1.
-// Return the Patch object on success, or NULL if no match is found.
-const Patch* FindMatchingPatch(uint8_t* sha1, Patch* patches, int num_patches) {
- int i;
- for (i = 0; i < num_patches; ++i) {
- if (memcmp(patches[i].sha1, sha1, SHA_DIGEST_SIZE) == 0) {
- return patches+i;
- }
- }
- return NULL;
-}
-
-// Returns 0 if the contents of the file (argv[2]) or the cached file
-// match any of the sha1's on the command line (argv[3:]). Returns
-// nonzero otherwise.
-int CheckMode(int argc, char** argv) {
- if (argc < 3) {
- fprintf(stderr, "no filename given\n");
- return 2;
- }
-
- int num_patches;
- Patch* patches;
- if (ParseShaArgs(argc-3, argv+3, &patches, &num_patches) != 0) { return 1; }
-
- FileContents file;
- file.data = NULL;
-
- if (LoadFileContents(argv[2], &file) != 0 ||
- FindMatchingPatch(file.sha1, patches, num_patches) == NULL) {
- fprintf(stderr, "file \"%s\" doesn't have any of expected "
- "sha1 sums; checking cache\n", argv[2]);
-
- free(file.data);
-
- // If the source file is missing or corrupted, it might be because
- // we were killed in the middle of patching it. A copy of it
- // should have been made in CACHE_TEMP_SOURCE. If that file
- // exists and matches the sha1 we're looking for, the check still
- // passes.
-
- if (LoadFileContents(CACHE_TEMP_SOURCE, &file) != 0) {
- fprintf(stderr, "failed to load cache file\n");
- return 1;
- }
-
- if (FindMatchingPatch(file.sha1, patches, num_patches) == NULL) {
- fprintf(stderr, "cache bits don't match any sha1 for \"%s\"\n",
- argv[2]);
- return 1;
- }
- }
-
- free(file.data);
- return 0;
-}
-
-int ShowLicenses() {
- ShowBSDiffLicense();
- return 0;
-}
-
-// 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) {
- fprintf(stderr, "failed to statfs %s: %s\n", filename, strerror(errno));
- return -1;
- }
- return sf.f_bsize * sf.f_bfree;
-}
-
-// This program 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 <file> is <tgt-sha1>, does nothing and exits
-// successfully.
-//
-// - otherwise, if the sha1 hash of <file> is <src-sha1>, applies the
-// bsdiff <patch> to <file> to produce a new file (the type of patch
-// is automatically detected from the file header). If that new
-// file has sha1 hash <tgt-sha1>, moves it to replace <file>, and
-// exits successfully.
-//
-// - otherwise, or if any error is encountered, exits with non-zero
-// status.
-
-int main(int argc, char** argv) {
- if (argc < 2) {
- usage:
- fprintf(stderr, "usage: %s <file> <tgt-sha1> <tgt-size> [<src-sha1>:<patch> ...]\n"
- " or %s -c <file> [<sha1> ...]\n"
- " or %s -s <bytes>\n"
- " or %s -l\n",
- argv[0], argv[0], argv[0], argv[0]);
- return 1;
- }
-
- if (strncmp(argv[1], "-l", 3) == 0) {
- return ShowLicenses();
- }
-
- if (strncmp(argv[1], "-c", 3) == 0) {
- return CheckMode(argc, argv);
- }
-
- if (strncmp(argv[1], "-s", 3) == 0) {
- if (argc != 3) {
- goto usage;
- }
- size_t bytes = strtol(argv[2], NULL, 10);
- if (MakeFreeSpaceOnCache(bytes) < 0) {
- printf("unable to make %ld bytes available on /cache\n", (long)bytes);
- return 1;
- } else {
- return 0;
- }
- }
-
- uint8_t target_sha1[SHA_DIGEST_SIZE];
-
- const char* source_filename = argv[1];
-
- // assume that source_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* source_fs = strdup(argv[1]);
- char* slash = strchr(source_fs+1, '/');
- if (slash != NULL) {
- *slash = '\0';
- }
-
- if (ParseSha1(argv[2], target_sha1) != 0) {
- fprintf(stderr, "failed to parse tgt-sha1 \"%s\"\n", argv[2]);
- return 1;
- }
-
- unsigned long target_size = strtoul(argv[3], NULL, 0);
-
- int num_patches;
- Patch* patches;
- if (ParseShaArgs(argc-4, argv+4, &patches, &num_patches) < 0) { return 1; }
-
- FileContents copy_file;
- FileContents source_file;
- const char* source_patch_filename = NULL;
- const char* copy_patch_filename = NULL;
- int made_copy = 0;
-
- if (LoadFileContents(source_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.
- fprintf(stderr, "\"%s\" is already target; no patch needed\n",
- source_filename);
- return 0;
- }
-
- const Patch* to_use =
- FindMatchingPatch(source_file.sha1, patches, num_patches);
- if (to_use != NULL) {
- source_patch_filename = to_use->patch_filename;
- }
- }
-
- if (source_patch_filename == NULL) {
- free(source_file.data);
- fprintf(stderr, "source file is bad; trying copy\n");
-
- if (LoadFileContents(CACHE_TEMP_SOURCE, &copy_file) < 0) {
- // fail.
- fprintf(stderr, "failed to read copy file\n");
- return 1;
- }
-
- const Patch* to_use =
- FindMatchingPatch(copy_file.sha1, patches, num_patches);
- if (to_use != NULL) {
- copy_patch_filename = to_use->patch_filename;
- }
-
- if (copy_patch_filename == NULL) {
- // fail.
- fprintf(stderr, "copy file doesn't match source SHA-1s either\n");
- return 1;
- }
- }
-
- // Is there enough room in the target filesystem to hold the patched file?
- size_t free_space = FreeSpaceForFile(source_fs);
- int enough_space = free_space > (target_size * 3 / 2); // 50% margin of error
- printf("target %ld bytes; free space %ld bytes; enough %d\n",
- (long)target_size, (long)free_space, enough_space);
-
- if (!enough_space && source_patch_filename != 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 (MakeFreeSpaceOnCache(source_file.size) < 0) {
- fprintf(stderr, "not enough free space on /cache\n");
- return 1;
- }
-
- if (SaveFileContents(CACHE_TEMP_SOURCE, source_file) < 0) {
- fprintf(stderr, "failed to back up source file\n");
- return 1;
- }
- made_copy = 1;
- unlink(source_filename);
-
- size_t free_space = FreeSpaceForFile(source_fs);
- printf("(now %ld bytes free for source)\n", (long)free_space);
- }
-
- FileContents* source_to_use;
- const char* patch_filename;
- if (source_patch_filename != NULL) {
- source_to_use = &source_file;
- patch_filename = source_patch_filename;
- } else {
- source_to_use = &copy_file;
- patch_filename = copy_patch_filename;
- }
-
- // We write the decoded output to "<file>.patch".
- char* outname = (char*)malloc(strlen(source_filename) + 10);
- strcpy(outname, source_filename);
- strcat(outname, ".patch");
- FILE* output = fopen(outname, "wb");
- if (output == NULL) {
- fprintf(stderr, "failed to patch file %s: %s\n",
- source_filename, strerror(errno));
- return 1;
- }
-
-#define MAX_HEADER_LENGTH 8
- unsigned char header[MAX_HEADER_LENGTH];
- FILE* patchf = fopen(patch_filename, "rb");
- if (patchf == NULL) {
- fprintf(stderr, "failed to open patch file %s: %s\n",
- patch_filename, strerror(errno));
- return 1;
- }
- int header_bytes_read = fread(header, 1, MAX_HEADER_LENGTH, patchf);
- fclose(patchf);
-
- SHA_CTX ctx;
- SHA_init(&ctx);
-
- if (header_bytes_read >= 4 &&
- header[0] == 0xd6 && header[1] == 0xc3 &&
- header[2] == 0xc4 && header[3] == 0) {
- // xdelta3 patches begin "VCD" (with the high bits set) followed
- // by a zero byte (the version number).
- fprintf(stderr, "error: xdelta3 patches no longer supported\n");
- return 1;
- } else if (header_bytes_read >= 8 &&
- memcmp(header, "BSDIFF40", 8) == 0) {
- int result = ApplyBSDiffPatch(source_to_use->data, source_to_use->size,
- patch_filename, output, &ctx);
- if (result != 0) {
- fprintf(stderr, "ApplyBSDiffPatch failed\n");
- return result;
- }
- } else {
- fprintf(stderr, "Unknown patch file format");
- return 1;
- }
-
- fflush(output);
- fsync(fileno(output));
- fclose(output);
-
- const uint8_t* current_target_sha1 = SHA_final(&ctx);
- if (memcmp(current_target_sha1, target_sha1, SHA_DIGEST_SIZE) != 0) {
- fprintf(stderr, "patch did not produce expected sha1\n");
- return 1;
- }
-
- // 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) {
- fprintf(stderr, "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) {
- fprintf(stderr, "chown of \"%s\" failed: %s\n", outname, strerror(errno));
- return 1;
- }
-
- // Finally, rename the .patch file to replace the original source file.
- if (rename(outname, source_filename) != 0) {
- fprintf(stderr, "rename of .patch to \"%s\" failed: %s\n",
- source_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;
-}
generated by cgit v1.1 at 2024-06-12 14:22:08 +0000