diff options
Diffstat (limited to 'applypatch/applypatch.c')
| -rw-r--r-- | applypatch/applypatch.c | 1359 |
1 files changed, 637 insertions, 722 deletions
diff --git a/applypatch/applypatch.c b/applypatch/applypatch.c index daf3729..99d3661 100644 --- a/applypatch/applypatch.c +++ b/applypatch/applypatch.c @@ -28,6 +28,7 @@ #include "mincrypt/sha.h" #include "applypatch.h" #include "mtdutils/mtdutils.h" +#include "edify/expr.h" int SaveFileContents(const char* filename, FileContents file); int LoadMTDContents(const char* filename, FileContents* file); @@ -39,57 +40,57 @@ static int mtd_partitions_scanned = 0; // 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; + file->data = NULL; - // A special 'filename' beginning with "MTD:" means to load the - // contents of an MTD partition. - if (strncmp(filename, "MTD:", 4) == 0) { - return LoadMTDContents(filename, file); - } + // A special 'filename' beginning with "MTD:" means to load the + // contents of an MTD partition. + if (strncmp(filename, "MTD:", 4) == 0) { + return LoadMTDContents(filename, file); + } - if (stat(filename, &file->st) != 0) { - printf("failed to stat \"%s\": %s\n", filename, strerror(errno)); - return -1; - } + if (stat(filename, &file->st) != 0) { + printf("failed to stat \"%s\": %s\n", filename, strerror(errno)); + return -1; + } - file->size = file->st.st_size; - file->data = malloc(file->size); + file->size = file->st.st_size; + file->data = malloc(file->size); - FILE* f = fopen(filename, "rb"); - if (f == NULL) { - printf("failed to open \"%s\": %s\n", filename, strerror(errno)); - free(file->data); - file->data = NULL; - return -1; - } + FILE* f = fopen(filename, "rb"); + if (f == NULL) { + printf("failed to open \"%s\": %s\n", filename, strerror(errno)); + free(file->data); + file->data = NULL; + return -1; + } - size_t bytes_read = fread(file->data, 1, file->size, f); - if (bytes_read != file->size) { - printf("short read of \"%s\" (%d bytes of %d)\n", - filename, bytes_read, file->size); - free(file->data); - file->data = NULL; - return -1; - } - fclose(f); + ssize_t bytes_read = fread(file->data, 1, file->size, f); + if (bytes_read != file->size) { + printf("short read of \"%s\" (%ld bytes of %ld)\n", + filename, (long)bytes_read, (long)file->size); + free(file->data); + file->data = NULL; + return -1; + } + fclose(f); - SHA(file->data, file->size, file->sha1); - return 0; + SHA(file->data, file->size, file->sha1); + return 0; } static size_t* size_array; // comparison function for qsort()ing an int array of indexes into // size_array[]. static int compare_size_indices(const void* a, const void* b) { - int aa = *(int*)a; - int bb = *(int*)b; - if (size_array[aa] < size_array[bb]) { - return -1; - } else if (size_array[aa] > size_array[bb]) { - return 1; - } else { - return 0; - } + int aa = *(int*)a; + int bb = *(int*)b; + if (size_array[aa] < size_array[bb]) { + return -1; + } else if (size_array[aa] > size_array[bb]) { + return 1; + } else { + return 0; + } } void FreeFileContents(FileContents* file) { @@ -113,239 +114,240 @@ void FreeFileContents(FileContents* file) { // hash of the data, and we'll do the load expecting to find one of // those hashes. int LoadMTDContents(const char* filename, FileContents* file) { - char* copy = strdup(filename); - const char* magic = strtok(copy, ":"); - if (strcmp(magic, "MTD") != 0) { - printf("LoadMTDContents called with bad filename (%s)\n", - filename); - return -1; - } - const char* partition = strtok(NULL, ":"); - - int i; - int colons = 0; - for (i = 0; filename[i] != '\0'; ++i) { - if (filename[i] == ':') { - ++colons; - } - } - if (colons < 3 || colons%2 == 0) { - printf("LoadMTDContents called with bad filename (%s)\n", - filename); - } - - int pairs = (colons-1)/2; // # of (size,sha1) pairs in filename - int* index = malloc(pairs * sizeof(int)); - size_t* size = malloc(pairs * sizeof(size_t)); - char** sha1sum = malloc(pairs * sizeof(char*)); - - for (i = 0; i < pairs; ++i) { - const char* size_str = strtok(NULL, ":"); - size[i] = strtol(size_str, NULL, 10); - if (size[i] == 0) { - printf("LoadMTDContents called with bad size (%s)\n", filename); - return -1; - } - sha1sum[i] = strtok(NULL, ":"); - index[i] = i; - } - - // sort the index[] array so it indexes the pairs in order of - // increasing size. - size_array = size; - qsort(index, pairs, sizeof(int), compare_size_indices); - - if (!mtd_partitions_scanned) { - mtd_scan_partitions(); - mtd_partitions_scanned = 1; - } - - const MtdPartition* mtd = mtd_find_partition_by_name(partition); - if (mtd == NULL) { - printf("mtd partition \"%s\" not found (loading %s)\n", - partition, filename); - return -1; - } - - MtdReadContext* ctx = mtd_read_partition(mtd); - if (ctx == NULL) { - printf("failed to initialize read of mtd partition \"%s\"\n", - partition); - return -1; - } - - SHA_CTX sha_ctx; - SHA_init(&sha_ctx); - uint8_t parsed_sha[SHA_DIGEST_SIZE]; - - // allocate enough memory to hold the largest size. - file->data = malloc(size[index[pairs-1]]); - char* p = (char*)file->data; - file->size = 0; // # bytes read so far - - for (i = 0; i < pairs; ++i) { - // Read enough additional bytes to get us up to the next size - // (again, we're trying the possibilities in order of increasing - // size). - size_t next = size[index[i]] - file->size; - size_t read = 0; - if (next > 0) { - read = mtd_read_data(ctx, p, next); - if (next != read) { - printf("short read (%d bytes of %d) for partition \"%s\"\n", - read, next, partition); - free(file->data); - file->data = NULL; + char* copy = strdup(filename); + const char* magic = strtok(copy, ":"); + if (strcmp(magic, "MTD") != 0) { + printf("LoadMTDContents called with bad filename (%s)\n", + filename); return -1; - } - SHA_update(&sha_ctx, p, read); - file->size += read; } + const char* partition = strtok(NULL, ":"); - // Duplicate the SHA context and finalize the duplicate so we can - // check it against this pair's expected hash. - SHA_CTX temp_ctx; - memcpy(&temp_ctx, &sha_ctx, sizeof(SHA_CTX)); - const uint8_t* sha_so_far = SHA_final(&temp_ctx); + int i; + int colons = 0; + for (i = 0; filename[i] != '\0'; ++i) { + if (filename[i] == ':') { + ++colons; + } + } + if (colons < 3 || colons%2 == 0) { + printf("LoadMTDContents called with bad filename (%s)\n", + filename); + } - if (ParseSha1(sha1sum[index[i]], parsed_sha) != 0) { - printf("failed to parse sha1 %s in %s\n", - sha1sum[index[i]], filename); - free(file->data); - file->data = NULL; - return -1; + int pairs = (colons-1)/2; // # of (size,sha1) pairs in filename + int* index = malloc(pairs * sizeof(int)); + size_t* size = malloc(pairs * sizeof(size_t)); + char** sha1sum = malloc(pairs * sizeof(char*)); + + for (i = 0; i < pairs; ++i) { + const char* size_str = strtok(NULL, ":"); + size[i] = strtol(size_str, NULL, 10); + if (size[i] == 0) { + printf("LoadMTDContents called with bad size (%s)\n", filename); + return -1; + } + sha1sum[i] = strtok(NULL, ":"); + index[i] = i; } - if (memcmp(sha_so_far, parsed_sha, SHA_DIGEST_SIZE) == 0) { - // we have a match. stop reading the partition; we'll return - // the data we've read so far. - printf("mtd read matched size %d sha %s\n", - size[index[i]], sha1sum[index[i]]); - break; + // sort the index[] array so it indexes the pairs in order of + // increasing size. + size_array = size; + qsort(index, pairs, sizeof(int), compare_size_indices); + + if (!mtd_partitions_scanned) { + mtd_scan_partitions(); + mtd_partitions_scanned = 1; } - p += read; - } + const MtdPartition* mtd = mtd_find_partition_by_name(partition); + if (mtd == NULL) { + printf("mtd partition \"%s\" not found (loading %s)\n", + partition, filename); + return -1; + } - mtd_read_close(ctx); + MtdReadContext* ctx = mtd_read_partition(mtd); + if (ctx == NULL) { + printf("failed to initialize read of mtd partition \"%s\"\n", + partition); + return -1; + } - if (i == pairs) { - // Ran off the end of the list of (size,sha1) pairs without - // finding a match. - printf("contents of MTD partition \"%s\" didn't match %s\n", - partition, filename); - free(file->data); - file->data = NULL; - return -1; - } + SHA_CTX sha_ctx; + SHA_init(&sha_ctx); + uint8_t parsed_sha[SHA_DIGEST_SIZE]; + + // allocate enough memory to hold the largest size. + file->data = malloc(size[index[pairs-1]]); + char* p = (char*)file->data; + file->size = 0; // # bytes read so far + + for (i = 0; i < pairs; ++i) { + // Read enough additional bytes to get us up to the next size + // (again, we're trying the possibilities in order of increasing + // size). + size_t next = size[index[i]] - file->size; + size_t read = 0; + if (next > 0) { + read = mtd_read_data(ctx, p, next); + if (next != read) { + printf("short read (%d bytes of %d) for partition \"%s\"\n", + read, next, partition); + free(file->data); + file->data = NULL; + return -1; + } + SHA_update(&sha_ctx, p, read); + file->size += read; + } + + // Duplicate the SHA context and finalize the duplicate so we can + // check it against this pair's expected hash. + SHA_CTX temp_ctx; + memcpy(&temp_ctx, &sha_ctx, sizeof(SHA_CTX)); + const uint8_t* sha_so_far = SHA_final(&temp_ctx); + + if (ParseSha1(sha1sum[index[i]], parsed_sha) != 0) { + printf("failed to parse sha1 %s in %s\n", + sha1sum[index[i]], filename); + free(file->data); + file->data = NULL; + return -1; + } + + if (memcmp(sha_so_far, parsed_sha, SHA_DIGEST_SIZE) == 0) { + // we have a match. stop reading the partition; we'll return + // the data we've read so far. + printf("mtd read matched size %d sha %s\n", + size[index[i]], sha1sum[index[i]]); + break; + } - const uint8_t* sha_final = SHA_final(&sha_ctx); - for (i = 0; i < SHA_DIGEST_SIZE; ++i) { - file->sha1[i] = sha_final[i]; - } + p += read; + } + + mtd_read_close(ctx); + + if (i == pairs) { + // Ran off the end of the list of (size,sha1) pairs without + // finding a match. + printf("contents of MTD partition \"%s\" didn't match %s\n", + partition, filename); + free(file->data); + file->data = NULL; + return -1; + } + + const uint8_t* sha_final = SHA_final(&sha_ctx); + for (i = 0; i < SHA_DIGEST_SIZE; ++i) { + file->sha1[i] = sha_final[i]; + } - // Fake some stat() info. - file->st.st_mode = 0644; - file->st.st_uid = 0; - file->st.st_gid = 0; + // Fake some stat() info. + file->st.st_mode = 0644; + file->st.st_uid = 0; + file->st.st_gid = 0; - free(copy); - free(index); - free(size); - free(sha1sum); + free(copy); + free(index); + free(size); + free(sha1sum); - return 0; + 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) { - int fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC); - if (fd < 0) { - printf("failed to open \"%s\" for write: %s\n", - filename, strerror(errno)); - return -1; - } + int fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC); + if (fd < 0) { + printf("failed to open \"%s\" for write: %s\n", + filename, strerror(errno)); + return -1; + } - size_t bytes_written = FileSink(file.data, file.size, &fd); - if (bytes_written != file.size) { - printf("short write of \"%s\" (%d bytes of %d) (%s)\n", - filename, bytes_written, file.size, strerror(errno)); + ssize_t bytes_written = FileSink(file.data, file.size, &fd); + if (bytes_written != file.size) { + printf("short write of \"%s\" (%ld bytes of %ld) (%s)\n", + filename, (long)bytes_written, (long)file.size, + strerror(errno)); + close(fd); + return -1; + } + fsync(fd); close(fd); - return -1; - } - fsync(fd); - close(fd); - if (chmod(filename, file.st.st_mode) != 0) { - printf("chmod of \"%s\" failed: %s\n", filename, strerror(errno)); - return -1; - } - if (chown(filename, file.st.st_uid, file.st.st_gid) != 0) { - printf("chown of \"%s\" failed: %s\n", filename, strerror(errno)); - return -1; - } + if (chmod(filename, file.st.st_mode) != 0) { + printf("chmod of \"%s\" failed: %s\n", filename, strerror(errno)); + return -1; + } + if (chown(filename, file.st.st_uid, file.st.st_gid) != 0) { + printf("chown of \"%s\" failed: %s\n", filename, strerror(errno)); + return -1; + } - return 0; + return 0; } // Write a memory buffer to target_mtd partition, a string of the form // "MTD:<partition>[:...]". Return 0 on success. int WriteToMTDPartition(unsigned char* data, size_t len, const char* target_mtd) { - char* partition = strchr(target_mtd, ':'); - if (partition == NULL) { - printf("bad MTD target name \"%s\"\n", target_mtd); - return -1; - } - ++partition; - // Trim off anything after a colon, eg "MTD:boot:blah:blah:blah...". - // We want just the partition name "boot". - partition = strdup(partition); - char* end = strchr(partition, ':'); - if (end != NULL) - *end = '\0'; - - if (!mtd_partitions_scanned) { - mtd_scan_partitions(); - mtd_partitions_scanned = 1; - } - - const MtdPartition* mtd = mtd_find_partition_by_name(partition); - if (mtd == NULL) { - printf("mtd partition \"%s\" not found for writing\n", partition); - return -1; - } + char* partition = strchr(target_mtd, ':'); + if (partition == NULL) { + printf("bad MTD target name \"%s\"\n", target_mtd); + return -1; + } + ++partition; + // Trim off anything after a colon, eg "MTD:boot:blah:blah:blah...". + // We want just the partition name "boot". + partition = strdup(partition); + char* end = strchr(partition, ':'); + if (end != NULL) + *end = '\0'; + + if (!mtd_partitions_scanned) { + mtd_scan_partitions(); + mtd_partitions_scanned = 1; + } - MtdWriteContext* ctx = mtd_write_partition(mtd); - if (ctx == NULL) { - printf("failed to init mtd partition \"%s\" for writing\n", - partition); - return -1; - } + const MtdPartition* mtd = mtd_find_partition_by_name(partition); + if (mtd == NULL) { + printf("mtd partition \"%s\" not found for writing\n", partition); + return -1; + } - size_t written = mtd_write_data(ctx, (char*)data, len); - if (written != len) { - printf("only wrote %d of %d bytes to MTD %s\n", - written, len, partition); - mtd_write_close(ctx); - return -1; - } + MtdWriteContext* ctx = mtd_write_partition(mtd); + if (ctx == NULL) { + printf("failed to init mtd partition \"%s\" for writing\n", + partition); + return -1; + } - if (mtd_erase_blocks(ctx, -1) < 0) { - printf("error finishing mtd write of %s\n", partition); - mtd_write_close(ctx); - return -1; - } + size_t written = mtd_write_data(ctx, (char*)data, len); + if (written != len) { + printf("only wrote %d of %d bytes to MTD %s\n", + written, len, partition); + mtd_write_close(ctx); + return -1; + } - if (mtd_write_close(ctx)) { - printf("error closing mtd write of %s\n", partition); - return -1; - } + if (mtd_erase_blocks(ctx, -1) < 0) { + printf("error finishing mtd write of %s\n", partition); + mtd_write_close(ctx); + return -1; + } - free(partition); - return 0; + if (mtd_write_close(ctx)) { + printf("error closing mtd write of %s\n", partition); + return -1; + } + + free(partition); + return 0; } @@ -354,547 +356,460 @@ int WriteToMTDPartition(unsigned char* data, size_t len, // 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) { - printf("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 { - printf("failed to parse filename \"%s\"\n", argv[i]); - return -1; + 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; + } } - } - - return 0; + if (*ps != '\0') 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; +// Search an array of sha1 strings for one matching the given sha1. +// Return the index of the match on success, or -1 if no match is +// found. +int FindMatchingPatch(uint8_t* sha1, char** const patch_sha1_str, + int num_patches) { + int i; + uint8_t patch_sha1[SHA_DIGEST_SIZE]; + for (i = 0; i < num_patches; ++i) { + if (ParseSha1(patch_sha1_str[i], patch_sha1) == 0 && + memcmp(patch_sha1, sha1, SHA_DIGEST_SIZE) == 0) { + return i; + } } - } - return NULL; + return -1; } // 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) { - printf("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; - - // It's okay to specify no sha1s; the check will pass if the - // LoadFileContents is successful. (Useful for reading MTD - // partitions, where the filename encodes the sha1s; no need to - // check them twice.) - if (LoadFileContents(argv[2], &file) != 0 || - (num_patches > 0 && - FindMatchingPatch(file.sha1, patches, num_patches) == NULL)) { - printf("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) { - printf("failed to load cache file\n"); - return 1; - } +int applypatch_check(const char* filename, + int num_patches, char** const patch_sha1_str) { + FileContents file; + file.data = NULL; + + // It's okay to specify no sha1s; the check will pass if the + // LoadFileContents is successful. (Useful for reading MTD + // partitions, where the filename encodes the sha1s; no need to + // check them twice.) + if (LoadFileContents(filename, &file) != 0 || + (num_patches > 0 && + FindMatchingPatch(file.sha1, patch_sha1_str, num_patches) < 0)) { + printf("file \"%s\" doesn't have any of expected " + "sha1 sums; checking cache\n", filename); + + 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) { + printf("failed to load cache file\n"); + return 1; + } - if (FindMatchingPatch(file.sha1, patches, num_patches) == NULL) { - printf("cache bits don't match any sha1 for \"%s\"\n", - argv[2]); - 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; + free(file.data); + return 0; } int ShowLicenses() { - ShowBSDiffLicense(); - return 0; + 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; - } - printf("wrote %d bytes to output\n", (int)done); - return done; + 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; + 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; + 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; + 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 program applies binary patches to files in a way that is safe + +// 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 <tgt-file> is <tgt-sha1>, does nothing and exits -// successfully. +// - if the sha1 hash of <target_filename> is <target_sha1_string>, +// does nothing and exits successfully. // -// - otherwise, if the sha1 hash of <src-file> is <src-sha1>, applies the -// bsdiff <patch> to <src-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 <tgt-file>, and -// exits successfully. Note that if <src-file> and <tgt-file> are -// not the same, <src-file> is NOT deleted on success. <tgt-file> -// may be the string "-" to mean "the same as src-file". +// - 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. // -// <src-file> (or <file> in check mode) may refer to an MTD partition -// to read the source data. See the comments for the -// LoadMTDContents() function above for the format of such a filename. -// -// -// As you might guess from the arguments, this function used to be -// main(); it was split out this way so applypatch could be built as a -// static library and linked into other executables as well. In the -// future only the library form will exist; we will not need to build -// this as a standalone executable. -// -// The arguments to this function are just the command-line of the -// standalone executable: -// -// <src-file> <tgt-file> <tgt-sha1> <tgt-size> [<src-sha1>:<patch> ...] -// to apply a patch. Returns 0 on success, 1 on failure. -// -// "-c" <file> [<sha1> ...] -// to check a file's contents against zero or more sha1s. Returns -// 0 if it matches any of them, 1 if it doesn't. -// -// "-s" <bytes> -// returns 0 if enough free space is available on /cache; 1 if it -// does not. -// -// "-l" -// shows open-source license information and returns 0. -// -// This function returns 2 if the arguments are not understood (in the -// standalone executable, this causes the usage message to be -// printed). -// -// TODO: make the interface more sensible for use as a library. - -int applypatch(int argc, char** argv) { - if (argc < 2) { - return 2; - } +// <source_filename> may refer to an MTD partition to read the source +// data. See the comments for the LoadMTDContents() 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; + } - if (strncmp(argv[1], "-l", 3) == 0) { - return ShowLicenses(); - } + 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; + } - if (strncmp(argv[1], "-c", 3) == 0) { - return CheckMode(argc, argv); - } + 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) == 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 (strncmp(argv[1], "-s", 3) == 0) { - if (argc != 3) { - return 2; + 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); } - 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]; - const char* target_filename = argv[2]; - if (target_filename[0] == '-' && - target_filename[1] == '\0') { - target_filename = source_filename; - } - - printf("\napplying patch to %s\n", source_filename); - - if (ParseSha1(argv[3], target_sha1) != 0) { - printf("failed to parse tgt-sha1 \"%s\"\n", argv[3]); - return 1; - } - - unsigned long target_size = strtoul(argv[4], NULL, 0); - - int num_patches; - Patch* patches; - if (ParseShaArgs(argc-5, argv+5, &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; - - // 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("\"%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); - } - - if (source_file.data != NULL) { - 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); - 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; - } - - 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. - 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, "MTD:", 4) == 0) { - // If the target is an MTD 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 MTD - // 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); - int enough_space = - (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_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 (strncmp(source_filename, "MTD:", 4) == 0) { - // It's impossible to free space on the target filesystem by - // deleting the source if the source is an MTD 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 MTD\n"); - return 1; + + 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 (MakeFreeSpaceOnCache(source_file.size) < 0) { - printf("not enough free space on /cache\n"); - return 1; + if (source_patch_value == NULL) { + free(source_file.data); + 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; } - if (SaveFileContents(CACHE_TEMP_SOURCE, source_file) < 0) { - printf("failed to back up source 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]; } - made_copy = 1; - unlink(source_filename); - size_t free_space = FreeSpaceForFile(target_fs); - printf("(now %ld bytes free for target)\n", (long)free_space); - } + if (copy_patch_value == NULL) { + // fail. + printf("copy file doesn't match source SHA-1s either\n"); + return 1; + } } - const char* patch_filename; - if (source_patch_filename != NULL) { - source_to_use = &source_file; - patch_filename = source_patch_filename; - } else { - source_to_use = ©_file; - patch_filename = copy_patch_filename; - } - - SinkFn sink = NULL; - void* token = NULL; - output = -1; - outname = NULL; - if (strncmp(target_filename, "MTD:", 4) == 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; - } - -#define MAX_HEADER_LENGTH 8 - unsigned char header[MAX_HEADER_LENGTH]; - FILE* patchf = fopen(patch_filename, "rb"); - if (patchf == NULL) { - printf("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_init(&ctx); - - int result; - - 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). - printf("error: xdelta3 patches no longer supported\n"); - return 1; - } else if (header_bytes_read >= 8 && - memcmp(header, "BSDIFF40", 8) == 0) { - result = ApplyBSDiffPatch(source_to_use->data, source_to_use->size, - patch_filename, 0, sink, token, &ctx); - } else if (header_bytes_read >= 8 && - memcmp(header, "IMGDIFF", 7) == 0 && - (header[7] == '1' || header[7] == '2')) { - result = ApplyImagePatch(source_to_use->data, source_to_use->size, - patch_filename, sink, token, &ctx); + 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 { - printf("Unknown patch file format\n"); - return 1; + strcpy(target_fs, target_filename); } - if (output >= 0) { - fsync(output); - close(output); + do { + // Is there enough room in the target filesystem to hold the patched + // file? + + if (strncmp(target_filename, "MTD:", 4) == 0) { + // If the target is an MTD 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 MTD + // 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); + int enough_space = + (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) { + // It's impossible to free space on the target filesystem by + // deleting the source if the source is an MTD 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 MTD\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, "MTD:", 4) == 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 (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); - } + if (output < 0) { + // Copy the temp file to the MTD partition. + if (WriteToMTDPartition(msi.buffer, msi.pos, target_filename) != 0) { + printf("write of patched data to %s failed\n", target_filename); + return 1; + } + free(msi.buffer); } 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 MTD partition. - if (WriteToMTDPartition(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; + // 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; } |