diff options
Diffstat (limited to 'updater/blockimg.c')
-rw-r--r-- | updater/blockimg.c | 645 |
1 files changed, 645 insertions, 0 deletions
diff --git a/updater/blockimg.c b/updater/blockimg.c new file mode 100644 index 000000000..c3319c973 --- /dev/null +++ b/updater/blockimg.c @@ -0,0 +1,645 @@ +/* + * Copyright (C) 2014 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include <ctype.h> +#include <errno.h> +#include <fcntl.h> +#include <inttypes.h> +#include <pthread.h> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <sys/ioctl.h> +#include <time.h> +#include <unistd.h> + +#include "applypatch/applypatch.h" +#include "edify/expr.h" +#include "mincrypt/sha.h" +#include "minzip/DirUtil.h" +#include "updater.h" + +#define BLOCKSIZE 4096 + +// Set this to 0 to interpret 'erase' transfers to mean do a +// BLKDISCARD ioctl (the normal behavior). Set to 1 to interpret +// erase to mean fill the region with zeroes. +#define DEBUG_ERASE 0 + +#ifndef BLKDISCARD +#define BLKDISCARD _IO(0x12,119) +#endif + +char* PrintSha1(const uint8_t* digest); + +typedef struct { + int count; + int size; + int pos[0]; +} RangeSet; + +static RangeSet* parse_range(char* text) { + char* save; + int num; + num = strtol(strtok_r(text, ",", &save), NULL, 0); + + RangeSet* out = malloc(sizeof(RangeSet) + num * sizeof(int)); + if (out == NULL) { + fprintf(stderr, "failed to allocate range of %lu bytes\n", + sizeof(RangeSet) + num * sizeof(int)); + exit(1); + } + out->count = num / 2; + out->size = 0; + int i; + for (i = 0; i < num; ++i) { + out->pos[i] = strtol(strtok_r(NULL, ",", &save), NULL, 0); + if (i%2) { + out->size += out->pos[i]; + } else { + out->size -= out->pos[i]; + } + } + + return out; +} + +static void readblock(int fd, uint8_t* data, size_t size) { + size_t so_far = 0; + while (so_far < size) { + ssize_t r = read(fd, data+so_far, size-so_far); + if (r < 0 && errno != EINTR) { + fprintf(stderr, "read failed: %s\n", strerror(errno)); + return; + } else { + so_far += r; + } + } +} + +static void writeblock(int fd, const uint8_t* data, size_t size) { + size_t written = 0; + while (written < size) { + ssize_t w = write(fd, data+written, size-written); + if (w < 0 && errno != EINTR) { + fprintf(stderr, "write failed: %s\n", strerror(errno)); + return; + } else { + written += w; + } + } +} + +static void check_lseek(int fd, off64_t offset, int whence) { + while (true) { + off64_t ret = lseek64(fd, offset, whence); + if (ret < 0) { + if (errno != EINTR) { + fprintf(stderr, "lseek64 failed: %s\n", strerror(errno)); + exit(1); + } + } else { + break; + } + } +} + +static void allocate(size_t size, uint8_t** buffer, size_t* buffer_alloc) { + // if the buffer's big enough, reuse it. + if (size <= *buffer_alloc) return; + + free(*buffer); + + *buffer = (uint8_t*) malloc(size); + if (*buffer == NULL) { + fprintf(stderr, "failed to allocate %zu bytes\n", size); + exit(1); + } + *buffer_alloc = size; +} + +typedef struct { + int fd; + RangeSet* tgt; + int p_block; + size_t p_remain; +} RangeSinkState; + +static ssize_t RangeSinkWrite(const uint8_t* data, ssize_t size, void* token) { + RangeSinkState* rss = (RangeSinkState*) token; + + if (rss->p_remain <= 0) { + fprintf(stderr, "range sink write overrun"); + exit(1); + } + + ssize_t written = 0; + while (size > 0) { + size_t write_now = size; + if (rss->p_remain < write_now) write_now = rss->p_remain; + writeblock(rss->fd, data, write_now); + data += write_now; + size -= write_now; + + rss->p_remain -= write_now; + written += write_now; + + if (rss->p_remain == 0) { + // move to the next block + ++rss->p_block; + if (rss->p_block < rss->tgt->count) { + rss->p_remain = (rss->tgt->pos[rss->p_block*2+1] - rss->tgt->pos[rss->p_block*2]) * BLOCKSIZE; + check_lseek(rss->fd, (off64_t)rss->tgt->pos[rss->p_block*2] * BLOCKSIZE, SEEK_SET); + } else { + // we can't write any more; return how many bytes have + // been written so far. + return written; + } + } + } + + return written; +} + +// All of the data for all the 'new' transfers is contained in one +// file in the update package, concatenated together in the order in +// which transfers.list will need it. We want to stream it out of the +// archive (it's compressed) without writing it to a temp file, but we +// can't write each section until it's that transfer's turn to go. +// +// To achieve this, we expand the new data from the archive in a +// background thread, and block that threads 'receive uncompressed +// data' function until the main thread has reached a point where we +// want some new data to be written. We signal the background thread +// with the destination for the data and block the main thread, +// waiting for the background thread to complete writing that section. +// Then it signals the main thread to wake up and goes back to +// blocking waiting for a transfer. +// +// NewThreadInfo is the struct used to pass information back and forth +// between the two threads. When the main thread wants some data +// written, it sets rss to the destination location and signals the +// condition. When the background thread is done writing, it clears +// rss and signals the condition again. + +typedef struct { + ZipArchive* za; + const ZipEntry* entry; + + RangeSinkState* rss; + + pthread_mutex_t mu; + pthread_cond_t cv; +} NewThreadInfo; + +static bool receive_new_data(const unsigned char* data, int size, void* cookie) { + NewThreadInfo* nti = (NewThreadInfo*) cookie; + + while (size > 0) { + // Wait for nti->rss to be non-NULL, indicating some of this + // data is wanted. + pthread_mutex_lock(&nti->mu); + while (nti->rss == NULL) { + pthread_cond_wait(&nti->cv, &nti->mu); + } + pthread_mutex_unlock(&nti->mu); + + // At this point nti->rss is set, and we own it. The main + // thread is waiting for it to disappear from nti. + ssize_t written = RangeSinkWrite(data, size, nti->rss); + data += written; + size -= written; + + if (nti->rss->p_block == nti->rss->tgt->count) { + // we have written all the bytes desired by this rss. + + pthread_mutex_lock(&nti->mu); + nti->rss = NULL; + pthread_cond_broadcast(&nti->cv); + pthread_mutex_unlock(&nti->mu); + } + } + + return true; +} + +static void* unzip_new_data(void* cookie) { + NewThreadInfo* nti = (NewThreadInfo*) cookie; + mzProcessZipEntryContents(nti->za, nti->entry, receive_new_data, nti); + return NULL; +} + +// args: +// - block device (or file) to modify in-place +// - transfer list (blob) +// - new data stream (filename within package.zip) +// - patch stream (filename within package.zip, must be uncompressed) + +Value* BlockImageUpdateFn(const char* name, State* state, int argc, Expr* argv[]) { + Value* blockdev_filename; + Value* transfer_list_value; + char* transfer_list = NULL; + Value* new_data_fn; + Value* patch_data_fn; + bool success = false; + + if (ReadValueArgs(state, argv, 4, &blockdev_filename, &transfer_list_value, + &new_data_fn, &patch_data_fn) < 0) { + return NULL; + } + + if (blockdev_filename->type != VAL_STRING) { + ErrorAbort(state, "blockdev_filename argument to %s must be string", name); + goto done; + } + if (transfer_list_value->type != VAL_BLOB) { + ErrorAbort(state, "transfer_list argument to %s must be blob", name); + goto done; + } + if (new_data_fn->type != VAL_STRING) { + ErrorAbort(state, "new_data_fn argument to %s must be string", name); + goto done; + } + if (patch_data_fn->type != VAL_STRING) { + ErrorAbort(state, "patch_data_fn argument to %s must be string", name); + goto done; + } + + UpdaterInfo* ui = (UpdaterInfo*)(state->cookie); + FILE* cmd_pipe = ui->cmd_pipe; + + ZipArchive* za = ((UpdaterInfo*)(state->cookie))->package_zip; + + const ZipEntry* patch_entry = mzFindZipEntry(za, patch_data_fn->data); + if (patch_entry == NULL) { + ErrorAbort(state, "%s(): no file \"%s\" in package", name, patch_data_fn->data); + goto done; + } + + uint8_t* patch_start = ((UpdaterInfo*)(state->cookie))->package_zip_addr + + mzGetZipEntryOffset(patch_entry); + + const ZipEntry* new_entry = mzFindZipEntry(za, new_data_fn->data); + if (new_entry == NULL) { + ErrorAbort(state, "%s(): no file \"%s\" in package", name, new_data_fn->data); + goto done; + } + + // The transfer list is a text file containing commands to + // transfer data from one place to another on the target + // partition. We parse it and execute the commands in order: + // + // zero [rangeset] + // - fill the indicated blocks with zeros + // + // new [rangeset] + // - fill the blocks with data read from the new_data file + // + // bsdiff patchstart patchlen [src rangeset] [tgt rangeset] + // imgdiff patchstart patchlen [src rangeset] [tgt rangeset] + // - read the source blocks, apply a patch, write result to + // target blocks. bsdiff or imgdiff specifies the type of + // patch. + // + // move [src rangeset] [tgt rangeset] + // - copy data from source blocks to target blocks (no patch + // needed; rangesets are the same size) + // + // erase [rangeset] + // - mark the given blocks as empty + // + // The creator of the transfer list will guarantee that no block + // is read (ie, used as the source for a patch or move) after it + // has been written. + // + // Within one command the source and target ranges may overlap so + // in general we need to read the entire source into memory before + // writing anything to the target blocks. + // + // All the patch data is concatenated into one patch_data file in + // the update package. It must be stored uncompressed because we + // memory-map it in directly from the archive. (Since patches are + // already compressed, we lose very little by not compressing + // their concatenation.) + + pthread_t new_data_thread; + NewThreadInfo nti; + nti.za = za; + nti.entry = new_entry; + nti.rss = NULL; + pthread_mutex_init(&nti.mu, NULL); + pthread_cond_init(&nti.cv, NULL); + + pthread_attr_t attr; + pthread_attr_init(&attr); + pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE); + pthread_create(&new_data_thread, &attr, unzip_new_data, &nti); + + int i, j; + + char* linesave; + char* wordsave; + + int fd = open(blockdev_filename->data, O_RDWR); + if (fd < 0) { + ErrorAbort(state, "failed to open %s: %s", blockdev_filename->data, strerror(errno)); + goto done; + } + + char* line; + char* word; + + // The data in transfer_list_value is not necessarily + // null-terminated, so we need to copy it to a new buffer and add + // the null that strtok_r will need. + transfer_list = malloc(transfer_list_value->size+1); + if (transfer_list == NULL) { + fprintf(stderr, "failed to allocate %zd bytes for transfer list\n", + transfer_list_value->size+1); + exit(1); + } + memcpy(transfer_list, transfer_list_value->data, transfer_list_value->size); + transfer_list[transfer_list_value->size] = '\0'; + + line = strtok_r(transfer_list, "\n", &linesave); + + // first line in transfer list is the version number; currently + // there's only version 1. + if (strcmp(line, "1") != 0) { + ErrorAbort(state, "unexpected transfer list version [%s]\n", line); + goto done; + } + + // second line in transfer list is the total number of blocks we + // expect to write. + line = strtok_r(NULL, "\n", &linesave); + int total_blocks = strtol(line, NULL, 0); + // shouldn't happen, but avoid divide by zero. + if (total_blocks == 0) ++total_blocks; + int blocks_so_far = 0; + + uint8_t* buffer = NULL; + size_t buffer_alloc = 0; + + // third and subsequent lines are all individual transfer commands. + for (line = strtok_r(NULL, "\n", &linesave); line; + line = strtok_r(NULL, "\n", &linesave)) { + char* style; + style = strtok_r(line, " ", &wordsave); + + if (strcmp("move", style) == 0) { + word = strtok_r(NULL, " ", &wordsave); + RangeSet* src = parse_range(word); + word = strtok_r(NULL, " ", &wordsave); + RangeSet* tgt = parse_range(word); + + printf(" moving %d blocks\n", src->size); + + allocate(src->size * BLOCKSIZE, &buffer, &buffer_alloc); + size_t p = 0; + for (i = 0; i < src->count; ++i) { + check_lseek(fd, (off64_t)src->pos[i*2] * BLOCKSIZE, SEEK_SET); + size_t sz = (src->pos[i*2+1] - src->pos[i*2]) * BLOCKSIZE; + readblock(fd, buffer+p, sz); + p += sz; + } + + p = 0; + for (i = 0; i < tgt->count; ++i) { + check_lseek(fd, (off64_t)tgt->pos[i*2] * BLOCKSIZE, SEEK_SET); + size_t sz = (tgt->pos[i*2+1] - tgt->pos[i*2]) * BLOCKSIZE; + writeblock(fd, buffer+p, sz); + p += sz; + } + + blocks_so_far += tgt->size; + fprintf(cmd_pipe, "set_progress %.4f\n", (double)blocks_so_far / total_blocks); + fflush(cmd_pipe); + + free(src); + free(tgt); + + } else if (strcmp("zero", style) == 0 || + (DEBUG_ERASE && strcmp("erase", style) == 0)) { + word = strtok_r(NULL, " ", &wordsave); + RangeSet* tgt = parse_range(word); + + printf(" zeroing %d blocks\n", tgt->size); + + allocate(BLOCKSIZE, &buffer, &buffer_alloc); + memset(buffer, 0, BLOCKSIZE); + for (i = 0; i < tgt->count; ++i) { + check_lseek(fd, (off64_t)tgt->pos[i*2] * BLOCKSIZE, SEEK_SET); + for (j = tgt->pos[i*2]; j < tgt->pos[i*2+1]; ++j) { + writeblock(fd, buffer, BLOCKSIZE); + } + } + + if (style[0] == 'z') { // "zero" but not "erase" + blocks_so_far += tgt->size; + fprintf(cmd_pipe, "set_progress %.4f\n", (double)blocks_so_far / total_blocks); + fflush(cmd_pipe); + } + + free(tgt); + } else if (strcmp("new", style) == 0) { + + word = strtok_r(NULL, " ", &wordsave); + RangeSet* tgt = parse_range(word); + + printf(" writing %d blocks of new data\n", tgt->size); + + RangeSinkState rss; + rss.fd = fd; + rss.tgt = tgt; + rss.p_block = 0; + rss.p_remain = (tgt->pos[1] - tgt->pos[0]) * BLOCKSIZE; + check_lseek(fd, (off64_t)tgt->pos[0] * BLOCKSIZE, SEEK_SET); + + pthread_mutex_lock(&nti.mu); + nti.rss = &rss; + pthread_cond_broadcast(&nti.cv); + while (nti.rss) { + pthread_cond_wait(&nti.cv, &nti.mu); + } + pthread_mutex_unlock(&nti.mu); + + blocks_so_far += tgt->size; + fprintf(cmd_pipe, "set_progress %.4f\n", (double)blocks_so_far / total_blocks); + fflush(cmd_pipe); + + free(tgt); + + } else if (strcmp("bsdiff", style) == 0 || + strcmp("imgdiff", style) == 0) { + word = strtok_r(NULL, " ", &wordsave); + size_t patch_offset = strtoul(word, NULL, 0); + word = strtok_r(NULL, " ", &wordsave); + size_t patch_len = strtoul(word, NULL, 0); + + word = strtok_r(NULL, " ", &wordsave); + RangeSet* src = parse_range(word); + word = strtok_r(NULL, " ", &wordsave); + RangeSet* tgt = parse_range(word); + + printf(" patching %d blocks to %d\n", src->size, tgt->size); + + // Read the source into memory. + allocate(src->size * BLOCKSIZE, &buffer, &buffer_alloc); + size_t p = 0; + for (i = 0; i < src->count; ++i) { + check_lseek(fd, (off64_t)src->pos[i*2] * BLOCKSIZE, SEEK_SET); + size_t sz = (src->pos[i*2+1] - src->pos[i*2]) * BLOCKSIZE; + readblock(fd, buffer+p, sz); + p += sz; + } + + Value patch_value; + patch_value.type = VAL_BLOB; + patch_value.size = patch_len; + patch_value.data = (char*)(patch_start + patch_offset); + + RangeSinkState rss; + rss.fd = fd; + rss.tgt = tgt; + rss.p_block = 0; + rss.p_remain = (tgt->pos[1] - tgt->pos[0]) * BLOCKSIZE; + check_lseek(fd, (off64_t)tgt->pos[0] * BLOCKSIZE, SEEK_SET); + + if (style[0] == 'i') { // imgdiff + ApplyImagePatch(buffer, src->size * BLOCKSIZE, + &patch_value, + &RangeSinkWrite, &rss, NULL, NULL); + } else { + ApplyBSDiffPatch(buffer, src->size * BLOCKSIZE, + &patch_value, 0, + &RangeSinkWrite, &rss, NULL); + } + + // We expect the output of the patcher to fill the tgt ranges exactly. + if (rss.p_block != tgt->count || rss.p_remain != 0) { + fprintf(stderr, "range sink underrun?\n"); + } + + blocks_so_far += tgt->size; + fprintf(cmd_pipe, "set_progress %.4f\n", (double)blocks_so_far / total_blocks); + fflush(cmd_pipe); + + free(src); + free(tgt); + } else if (!DEBUG_ERASE && strcmp("erase", style) == 0) { + struct stat st; + if (fstat(fd, &st) == 0 && S_ISBLK(st.st_mode)) { + word = strtok_r(NULL, " ", &wordsave); + RangeSet* tgt = parse_range(word); + + printf(" erasing %d blocks\n", tgt->size); + + for (i = 0; i < tgt->count; ++i) { + uint64_t range[2]; + // offset in bytes + range[0] = tgt->pos[i*2] * (uint64_t)BLOCKSIZE; + // len in bytes + range[1] = (tgt->pos[i*2+1] - tgt->pos[i*2]) * (uint64_t)BLOCKSIZE; + + if (ioctl(fd, BLKDISCARD, &range) < 0) { + printf(" blkdiscard failed: %s\n", strerror(errno)); + } + } + + free(tgt); + } else { + printf(" ignoring erase (not block device)\n"); + } + } else { + fprintf(stderr, "unknown transfer style \"%s\"\n", style); + exit(1); + } + } + + pthread_join(new_data_thread, NULL); + success = true; + + free(buffer); + printf("wrote %d blocks; expected %d\n", blocks_so_far, total_blocks); + printf("max alloc needed was %zu\n", buffer_alloc); + + done: + free(transfer_list); + FreeValue(blockdev_filename); + FreeValue(transfer_list_value); + FreeValue(new_data_fn); + FreeValue(patch_data_fn); + return StringValue(success ? strdup("t") : strdup("")); +} + +Value* RangeSha1Fn(const char* name, State* state, int argc, Expr* argv[]) { + Value* blockdev_filename; + Value* ranges; + const uint8_t* digest = NULL; + if (ReadValueArgs(state, argv, 2, &blockdev_filename, &ranges) < 0) { + return NULL; + } + + if (blockdev_filename->type != VAL_STRING) { + ErrorAbort(state, "blockdev_filename argument to %s must be string", name); + goto done; + } + if (ranges->type != VAL_STRING) { + ErrorAbort(state, "ranges argument to %s must be string", name); + goto done; + } + + int fd = open(blockdev_filename->data, O_RDWR); + if (fd < 0) { + ErrorAbort(state, "failed to open %s: %s", blockdev_filename->data, strerror(errno)); + goto done; + } + + RangeSet* rs = parse_range(ranges->data); + uint8_t buffer[BLOCKSIZE]; + + SHA_CTX ctx; + SHA_init(&ctx); + + int i, j; + for (i = 0; i < rs->count; ++i) { + check_lseek(fd, (off64_t)rs->pos[i*2] * BLOCKSIZE, SEEK_SET); + for (j = rs->pos[i*2]; j < rs->pos[i*2+1]; ++j) { + readblock(fd, buffer, BLOCKSIZE); + SHA_update(&ctx, buffer, BLOCKSIZE); + } + } + digest = SHA_final(&ctx); + close(fd); + + done: + FreeValue(blockdev_filename); + FreeValue(ranges); + if (digest == NULL) { + return StringValue(strdup("")); + } else { + return StringValue(PrintSha1(digest)); + } +} + +void RegisterBlockImageFunctions() { + RegisterFunction("block_image_update", BlockImageUpdateFn); + RegisterFunction("range_sha1", RangeSha1Fn); +} |