diff options
Diffstat (limited to 'updater/blockimg.cpp')
-rw-r--r-- | updater/blockimg.cpp | 2011 |
1 files changed, 2011 insertions, 0 deletions
diff --git a/updater/blockimg.cpp b/updater/blockimg.cpp new file mode 100644 index 000000000..310bbf94c --- /dev/null +++ b/updater/blockimg.cpp @@ -0,0 +1,2011 @@ +/* + * 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 <dirent.h> +#include <fcntl.h> +#include <inttypes.h> +#include <libgen.h> +#include <linux/fs.h> +#include <pthread.h> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/stat.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/Hash.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 + +#define STASH_DIRECTORY_BASE "/cache/recovery" +#define STASH_DIRECTORY_MODE 0700 +#define STASH_FILE_MODE 0600 + +char* PrintSha1(const uint8_t* digest); + +typedef struct { + int count; + int size; + int pos[0]; +} RangeSet; + +#define RANGESET_MAX_POINTS \ + ((int)((INT_MAX / sizeof(int)) - sizeof(RangeSet))) + +static RangeSet* parse_range(char* text) { + char* save; + char* token; + int num; + long int val; + RangeSet* out = NULL; + size_t bufsize; + + if (!text) { + goto err; + } + + token = strtok_r(text, ",", &save); + + if (!token) { + goto err; + } + + val = strtol(token, NULL, 0); + + if (val < 2 || val > RANGESET_MAX_POINTS) { + goto err; + } else if (val % 2) { + goto err; // must be even + } + + num = (int) val; + bufsize = sizeof(RangeSet) + num * sizeof(int); + + out = reinterpret_cast<RangeSet*>(malloc(bufsize)); + + if (!out) { + fprintf(stderr, "failed to allocate range of %zu bytes\n", bufsize); + goto err; + } + + out->count = num / 2; + out->size = 0; + + for (int i = 0; i < num; ++i) { + token = strtok_r(NULL, ",", &save); + + if (!token) { + goto err; + } + + val = strtol(token, NULL, 0); + + if (val < 0 || val > INT_MAX) { + goto err; + } + + out->pos[i] = (int) val; + + if (i % 2) { + if (out->pos[i - 1] >= out->pos[i]) { + goto err; // empty or negative range + } + + if (out->size > INT_MAX - out->pos[i]) { + goto err; // overflow + } + + out->size += out->pos[i]; + } else { + if (out->size < 0) { + goto err; + } + + out->size -= out->pos[i]; + } + } + + if (out->size <= 0) { + goto err; + } + + return out; + +err: + fprintf(stderr, "failed to parse range '%s'\n", text ? text : "NULL"); + exit(1); +} + +static int range_overlaps(RangeSet* r1, RangeSet* r2) { + int i, j, r1_0, r1_1, r2_0, r2_1; + + if (!r1 || !r2) { + return 0; + } + + for (i = 0; i < r1->count; ++i) { + r1_0 = r1->pos[i * 2]; + r1_1 = r1->pos[i * 2 + 1]; + + for (j = 0; j < r2->count; ++j) { + r2_0 = r2->pos[j * 2]; + r2_1 = r2->pos[j * 2 + 1]; + + if (!(r2_0 >= r1_1 || r1_0 >= r2_1)) { + return 1; + } + } + } + + return 0; +} + +static int read_all(int fd, uint8_t* data, size_t size) { + size_t so_far = 0; + while (so_far < size) { + ssize_t r = TEMP_FAILURE_RETRY(read(fd, data+so_far, size-so_far)); + if (r == -1) { + fprintf(stderr, "read failed: %s\n", strerror(errno)); + return -1; + } + so_far += r; + } + return 0; +} + +static int write_all(int fd, const uint8_t* data, size_t size) { + size_t written = 0; + while (written < size) { + ssize_t w = TEMP_FAILURE_RETRY(write(fd, data+written, size-written)); + if (w == -1) { + fprintf(stderr, "write failed: %s\n", strerror(errno)); + return -1; + } + written += w; + } + + if (fsync(fd) == -1) { + fprintf(stderr, "fsync failed: %s\n", strerror(errno)); + return -1; + } + + return 0; +} + +static bool check_lseek(int fd, off64_t offset, int whence) { + off64_t rc = TEMP_FAILURE_RETRY(lseek64(fd, offset, whence)); + if (rc == -1) { + fprintf(stderr, "lseek64 failed: %s\n", strerror(errno)); + return false; + } + return true; +} + +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"); + return 0; + } + + ssize_t written = 0; + while (size > 0) { + size_t write_now = size; + + if (rss->p_remain < write_now) { + write_now = rss->p_remain; + } + + if (write_all(rss->fd, data, write_now) == -1) { + break; + } + + 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; + + if (!check_lseek(rss->fd, (off64_t)rss->tgt->pos[rss->p_block*2] * BLOCKSIZE, + SEEK_SET)) { + break; + } + } else { + // we can't write any more; return how many bytes have + // been written so far. + break; + } + } + } + + 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; +} + +static int ReadBlocks(RangeSet* src, uint8_t* buffer, int fd) { + int i; + size_t p = 0; + size_t size; + + if (!src || !buffer) { + return -1; + } + + for (i = 0; i < src->count; ++i) { + if (!check_lseek(fd, (off64_t) src->pos[i * 2] * BLOCKSIZE, SEEK_SET)) { + return -1; + } + + size = (src->pos[i * 2 + 1] - src->pos[i * 2]) * BLOCKSIZE; + + if (read_all(fd, buffer + p, size) == -1) { + return -1; + } + + p += size; + } + + return 0; +} + +static int WriteBlocks(RangeSet* tgt, uint8_t* buffer, int fd) { + int i; + size_t p = 0; + size_t size; + + if (!tgt || !buffer) { + return -1; + } + + for (i = 0; i < tgt->count; ++i) { + if (!check_lseek(fd, (off64_t) tgt->pos[i * 2] * BLOCKSIZE, SEEK_SET)) { + return -1; + } + + size = (tgt->pos[i * 2 + 1] - tgt->pos[i * 2]) * BLOCKSIZE; + + if (write_all(fd, buffer + p, size) == -1) { + return -1; + } + + p += size; + } + + return 0; +} + +// Do a source/target load for move/bsdiff/imgdiff in version 1. +// 'wordsave' is the save_ptr of a strtok_r()-in-progress. We expect +// to parse the remainder of the string as: +// +// <src_range> <tgt_range> +// +// The source range is loaded into the provided buffer, reallocating +// it to make it larger if necessary. The target ranges are returned +// in *tgt, if tgt is non-NULL. + +static int LoadSrcTgtVersion1(char** wordsave, RangeSet** tgt, int* src_blocks, + uint8_t** buffer, size_t* buffer_alloc, int fd) { + char* word; + int rc; + + word = strtok_r(NULL, " ", wordsave); + RangeSet* src = parse_range(word); + + if (tgt != NULL) { + word = strtok_r(NULL, " ", wordsave); + *tgt = parse_range(word); + } + + allocate(src->size * BLOCKSIZE, buffer, buffer_alloc); + rc = ReadBlocks(src, *buffer, fd); + *src_blocks = src->size; + + free(src); + return rc; +} + +static int VerifyBlocks(const char *expected, const uint8_t *buffer, + size_t blocks, int printerror) { + char* hexdigest = NULL; + int rc = -1; + uint8_t digest[SHA_DIGEST_SIZE]; + + if (!expected || !buffer) { + return rc; + } + + SHA_hash(buffer, blocks * BLOCKSIZE, digest); + hexdigest = PrintSha1(digest); + + if (hexdigest != NULL) { + rc = strcmp(expected, hexdigest); + + if (rc != 0 && printerror) { + fprintf(stderr, "failed to verify blocks (expected %s, read %s)\n", + expected, hexdigest); + } + + free(hexdigest); + } + + return rc; +} + +static char* GetStashFileName(const char* base, const char* id, const char* postfix) { + char* fn; + int len; + int res; + + if (base == NULL) { + return NULL; + } + + if (id == NULL) { + id = ""; + } + + if (postfix == NULL) { + postfix = ""; + } + + len = strlen(STASH_DIRECTORY_BASE) + 1 + strlen(base) + 1 + strlen(id) + strlen(postfix) + 1; + fn = reinterpret_cast<char*>(malloc(len)); + + if (fn == NULL) { + fprintf(stderr, "failed to malloc %d bytes for fn\n", len); + return NULL; + } + + res = snprintf(fn, len, STASH_DIRECTORY_BASE "/%s/%s%s", base, id, postfix); + + if (res < 0 || res >= len) { + fprintf(stderr, "failed to format file name (return value %d)\n", res); + free(fn); + return NULL; + } + + return fn; +} + +typedef void (*StashCallback)(const char*, void*); + +// Does a best effort enumeration of stash files. Ignores possible non-file +// items in the stash directory and continues despite of errors. Calls the +// 'callback' function for each file and passes 'data' to the function as a +// parameter. + +static void EnumerateStash(const char* dirname, StashCallback callback, void* data) { + char* fn; + DIR* directory; + int len; + int res; + struct dirent* item; + + if (dirname == NULL || callback == NULL) { + return; + } + + directory = opendir(dirname); + + if (directory == NULL) { + if (errno != ENOENT) { + fprintf(stderr, "opendir \"%s\" failed: %s\n", dirname, strerror(errno)); + } + return; + } + + while ((item = readdir(directory)) != NULL) { + if (item->d_type != DT_REG) { + continue; + } + + len = strlen(dirname) + 1 + strlen(item->d_name) + 1; + fn = reinterpret_cast<char*>(malloc(len)); + + if (fn == NULL) { + fprintf(stderr, "failed to malloc %d bytes for fn\n", len); + continue; + } + + res = snprintf(fn, len, "%s/%s", dirname, item->d_name); + + if (res < 0 || res >= len) { + fprintf(stderr, "failed to format file name (return value %d)\n", res); + free(fn); + continue; + } + + callback(fn, data); + free(fn); + } + + if (closedir(directory) == -1) { + fprintf(stderr, "closedir \"%s\" failed: %s\n", dirname, strerror(errno)); + } +} + +static void UpdateFileSize(const char* fn, void* data) { + int* size = (int*) data; + struct stat st; + + if (!fn || !data) { + return; + } + + if (stat(fn, &st) == -1) { + fprintf(stderr, "stat \"%s\" failed: %s\n", fn, strerror(errno)); + return; + } + + *size += st.st_size; +} + +// Deletes the stash directory and all files in it. Assumes that it only +// contains files. There is nothing we can do about unlikely, but possible +// errors, so they are merely logged. + +static void DeleteFile(const char* fn, void* data) { + if (fn) { + fprintf(stderr, "deleting %s\n", fn); + + if (unlink(fn) == -1 && errno != ENOENT) { + fprintf(stderr, "unlink \"%s\" failed: %s\n", fn, strerror(errno)); + } + } +} + +static void DeletePartial(const char* fn, void* data) { + if (fn && strstr(fn, ".partial") != NULL) { + DeleteFile(fn, data); + } +} + +static void DeleteStash(const char* base) { + char* dirname; + + if (base == NULL) { + return; + } + + dirname = GetStashFileName(base, NULL, NULL); + + if (dirname == NULL) { + return; + } + + fprintf(stderr, "deleting stash %s\n", base); + EnumerateStash(dirname, DeleteFile, NULL); + + if (rmdir(dirname) == -1) { + if (errno != ENOENT && errno != ENOTDIR) { + fprintf(stderr, "rmdir \"%s\" failed: %s\n", dirname, strerror(errno)); + } + } + + free(dirname); +} + +static int LoadStash(const char* base, const char* id, int verify, int* blocks, uint8_t** buffer, + size_t* buffer_alloc, int printnoent) { + char *fn = NULL; + int blockcount = 0; + int fd = -1; + int rc = -1; + int res; + struct stat st; + + if (!base || !id || !buffer || !buffer_alloc) { + goto lsout; + } + + if (!blocks) { + blocks = &blockcount; + } + + fn = GetStashFileName(base, id, NULL); + + if (fn == NULL) { + goto lsout; + } + + res = stat(fn, &st); + + if (res == -1) { + if (errno != ENOENT || printnoent) { + fprintf(stderr, "stat \"%s\" failed: %s\n", fn, strerror(errno)); + } + goto lsout; + } + + fprintf(stderr, " loading %s\n", fn); + + if ((st.st_size % BLOCKSIZE) != 0) { + fprintf(stderr, "%s size %" PRId64 " not multiple of block size %d", + fn, static_cast<int64_t>(st.st_size), BLOCKSIZE); + goto lsout; + } + + fd = TEMP_FAILURE_RETRY(open(fn, O_RDONLY)); + + if (fd == -1) { + fprintf(stderr, "open \"%s\" failed: %s\n", fn, strerror(errno)); + goto lsout; + } + + allocate(st.st_size, buffer, buffer_alloc); + + if (read_all(fd, *buffer, st.st_size) == -1) { + goto lsout; + } + + *blocks = st.st_size / BLOCKSIZE; + + if (verify && VerifyBlocks(id, *buffer, *blocks, 1) != 0) { + fprintf(stderr, "unexpected contents in %s\n", fn); + DeleteFile(fn, NULL); + goto lsout; + } + + rc = 0; + +lsout: + if (fd != -1) { + close(fd); + } + + if (fn) { + free(fn); + } + + return rc; +} + +static int WriteStash(const char* base, const char* id, int blocks, uint8_t* buffer, + int checkspace, int *exists) { + char *fn = NULL; + char *cn = NULL; + int fd = -1; + int rc = -1; + int dfd = -1; + int res; + struct stat st; + + if (base == NULL || buffer == NULL) { + goto wsout; + } + + if (checkspace && CacheSizeCheck(blocks * BLOCKSIZE) != 0) { + fprintf(stderr, "not enough space to write stash\n"); + goto wsout; + } + + fn = GetStashFileName(base, id, ".partial"); + cn = GetStashFileName(base, id, NULL); + + if (fn == NULL || cn == NULL) { + goto wsout; + } + + if (exists) { + res = stat(cn, &st); + + if (res == 0) { + // The file already exists and since the name is the hash of the contents, + // it's safe to assume the contents are identical (accidental hash collisions + // are unlikely) + fprintf(stderr, " skipping %d existing blocks in %s\n", blocks, cn); + *exists = 1; + rc = 0; + goto wsout; + } + + *exists = 0; + } + + fprintf(stderr, " writing %d blocks to %s\n", blocks, cn); + + fd = TEMP_FAILURE_RETRY(open(fn, O_WRONLY | O_CREAT | O_TRUNC | O_SYNC, STASH_FILE_MODE)); + + if (fd == -1) { + fprintf(stderr, "failed to create \"%s\": %s\n", fn, strerror(errno)); + goto wsout; + } + + if (write_all(fd, buffer, blocks * BLOCKSIZE) == -1) { + goto wsout; + } + + if (fsync(fd) == -1) { + fprintf(stderr, "fsync \"%s\" failed: %s\n", fn, strerror(errno)); + goto wsout; + } + + if (rename(fn, cn) == -1) { + fprintf(stderr, "rename(\"%s\", \"%s\") failed: %s\n", fn, cn, strerror(errno)); + goto wsout; + } + + const char* dname; + dname = dirname(cn); + dfd = TEMP_FAILURE_RETRY(open(dname, O_RDONLY | O_DIRECTORY)); + + if (dfd == -1) { + fprintf(stderr, "failed to open \"%s\" failed: %s\n", dname, strerror(errno)); + goto wsout; + } + + if (fsync(dfd) == -1) { + fprintf(stderr, "fsync \"%s\" failed: %s\n", dname, strerror(errno)); + goto wsout; + } + + rc = 0; + +wsout: + if (fd != -1) { + close(fd); + } + + if (dfd != -1) { + close(dfd); + } + + if (fn) { + free(fn); + } + + if (cn) { + free(cn); + } + + return rc; +} + +// Creates a directory for storing stash files and checks if the /cache partition +// hash enough space for the expected amount of blocks we need to store. Returns +// >0 if we created the directory, zero if it existed already, and <0 of failure. + +static int CreateStash(State* state, int maxblocks, const char* blockdev, char** base) { + char* dirname = NULL; + const uint8_t* digest; + int rc = -1; + int res; + int size = 0; + SHA_CTX ctx; + struct stat st; + + if (blockdev == NULL || base == NULL) { + goto csout; + } + + // Stash directory should be different for each partition to avoid conflicts + // when updating multiple partitions at the same time, so we use the hash of + // the block device name as the base directory + SHA_init(&ctx); + SHA_update(&ctx, blockdev, strlen(blockdev)); + digest = SHA_final(&ctx); + *base = PrintSha1(digest); + + if (*base == NULL) { + goto csout; + } + + dirname = GetStashFileName(*base, NULL, NULL); + + if (dirname == NULL) { + goto csout; + } + + res = stat(dirname, &st); + + if (res == -1 && errno != ENOENT) { + ErrorAbort(state, "stat \"%s\" failed: %s\n", dirname, strerror(errno)); + goto csout; + } else if (res != 0) { + fprintf(stderr, "creating stash %s\n", dirname); + res = mkdir(dirname, STASH_DIRECTORY_MODE); + + if (res != 0) { + ErrorAbort(state, "mkdir \"%s\" failed: %s\n", dirname, strerror(errno)); + goto csout; + } + + if (CacheSizeCheck(maxblocks * BLOCKSIZE) != 0) { + ErrorAbort(state, "not enough space for stash\n"); + goto csout; + } + + rc = 1; // Created directory + goto csout; + } + + fprintf(stderr, "using existing stash %s\n", dirname); + + // If the directory already exists, calculate the space already allocated to + // stash files and check if there's enough for all required blocks. Delete any + // partially completed stash files first. + + EnumerateStash(dirname, DeletePartial, NULL); + EnumerateStash(dirname, UpdateFileSize, &size); + + size = (maxblocks * BLOCKSIZE) - size; + + if (size > 0 && CacheSizeCheck(size) != 0) { + ErrorAbort(state, "not enough space for stash (%d more needed)\n", size); + goto csout; + } + + rc = 0; // Using existing directory + +csout: + if (dirname) { + free(dirname); + } + + return rc; +} + +static int SaveStash(const char* base, char** wordsave, uint8_t** buffer, size_t* buffer_alloc, + int fd, int usehash, int* isunresumable) { + char *id = NULL; + int blocks = 0; + + if (!wordsave || !buffer || !buffer_alloc || !isunresumable) { + return -1; + } + + id = strtok_r(NULL, " ", wordsave); + + if (id == NULL) { + fprintf(stderr, "missing id field in stash command\n"); + return -1; + } + + if (usehash && LoadStash(base, id, 1, &blocks, buffer, buffer_alloc, 0) == 0) { + // Stash file already exists and has expected contents. Do not + // read from source again, as the source may have been already + // overwritten during a previous attempt. + return 0; + } + + if (LoadSrcTgtVersion1(wordsave, NULL, &blocks, buffer, buffer_alloc, fd) == -1) { + return -1; + } + + if (usehash && VerifyBlocks(id, *buffer, blocks, 1) != 0) { + // Source blocks have unexpected contents. If we actually need this + // data later, this is an unrecoverable error. However, the command + // that uses the data may have already completed previously, so the + // possible failure will occur during source block verification. + fprintf(stderr, "failed to load source blocks for stash %s\n", id); + return 0; + } + + fprintf(stderr, "stashing %d blocks to %s\n", blocks, id); + return WriteStash(base, id, blocks, *buffer, 0, NULL); +} + +static int FreeStash(const char* base, const char* id) { + char *fn = NULL; + + if (base == NULL || id == NULL) { + return -1; + } + + fn = GetStashFileName(base, id, NULL); + + if (fn == NULL) { + return -1; + } + + DeleteFile(fn, NULL); + free(fn); + + return 0; +} + +static void MoveRange(uint8_t* dest, RangeSet* locs, const uint8_t* source) { + // source contains packed data, which we want to move to the + // locations given in *locs in the dest buffer. source and dest + // may be the same buffer. + + int start = locs->size; + int i; + for (i = locs->count-1; i >= 0; --i) { + int blocks = locs->pos[i*2+1] - locs->pos[i*2]; + start -= blocks; + memmove(dest + (locs->pos[i*2] * BLOCKSIZE), source + (start * BLOCKSIZE), + blocks * BLOCKSIZE); + } +} + +// Do a source/target load for move/bsdiff/imgdiff in version 2. +// 'wordsave' is the save_ptr of a strtok_r()-in-progress. We expect +// to parse the remainder of the string as one of: +// +// <tgt_range> <src_block_count> <src_range> +// (loads data from source image only) +// +// <tgt_range> <src_block_count> - <[stash_id:stash_range] ...> +// (loads data from stashes only) +// +// <tgt_range> <src_block_count> <src_range> <src_loc> <[stash_id:stash_range] ...> +// (loads data from both source image and stashes) +// +// On return, buffer is filled with the loaded source data (rearranged +// and combined with stashed data as necessary). buffer may be +// reallocated if needed to accommodate the source data. *tgt is the +// target RangeSet. Any stashes required are loaded using LoadStash. + +static int LoadSrcTgtVersion2(char** wordsave, RangeSet** tgt, int* src_blocks, + uint8_t** buffer, size_t* buffer_alloc, int fd, + const char* stashbase, int* overlap) { + char* word; + char* colonsave; + char* colon; + int res; + RangeSet* locs; + size_t stashalloc = 0; + uint8_t* stash = NULL; + + if (tgt != NULL) { + word = strtok_r(NULL, " ", wordsave); + *tgt = parse_range(word); + } + + word = strtok_r(NULL, " ", wordsave); + *src_blocks = strtol(word, NULL, 0); + + allocate(*src_blocks * BLOCKSIZE, buffer, buffer_alloc); + + word = strtok_r(NULL, " ", wordsave); + if (word[0] == '-' && word[1] == '\0') { + // no source ranges, only stashes + } else { + RangeSet* src = parse_range(word); + res = ReadBlocks(src, *buffer, fd); + + if (overlap && tgt) { + *overlap = range_overlaps(src, *tgt); + } + + free(src); + + if (res == -1) { + return -1; + } + + word = strtok_r(NULL, " ", wordsave); + if (word == NULL) { + // no stashes, only source range + return 0; + } + + locs = parse_range(word); + MoveRange(*buffer, locs, *buffer); + free(locs); + } + + while ((word = strtok_r(NULL, " ", wordsave)) != NULL) { + // Each word is a an index into the stash table, a colon, and + // then a rangeset describing where in the source block that + // stashed data should go. + colonsave = NULL; + colon = strtok_r(word, ":", &colonsave); + + res = LoadStash(stashbase, colon, 0, NULL, &stash, &stashalloc, 1); + + if (res == -1) { + // These source blocks will fail verification if used later, but we + // will let the caller decide if this is a fatal failure + fprintf(stderr, "failed to load stash %s\n", colon); + continue; + } + + colon = strtok_r(NULL, ":", &colonsave); + locs = parse_range(colon); + + MoveRange(*buffer, locs, stash); + free(locs); + } + + if (stash) { + free(stash); + } + + return 0; +} + +// Parameters for transfer list command functions +typedef struct { + char* cmdname; + char* cpos; + char* freestash; + char* stashbase; + int canwrite; + int createdstash; + int fd; + int foundwrites; + int isunresumable; + int version; + int written; + NewThreadInfo nti; + pthread_t thread; + size_t bufsize; + uint8_t* buffer; + uint8_t* patch_start; +} CommandParameters; + +// Do a source/target load for move/bsdiff/imgdiff in version 3. +// +// Parameters are the same as for LoadSrcTgtVersion2, except for 'onehash', which +// tells the function whether to expect separate source and targe block hashes, or +// if they are both the same and only one hash should be expected, and +// 'isunresumable', which receives a non-zero value if block verification fails in +// a way that the update cannot be resumed anymore. +// +// If the function is unable to load the necessary blocks or their contents don't +// match the hashes, the return value is -1 and the command should be aborted. +// +// If the return value is 1, the command has already been completed according to +// the contents of the target blocks, and should not be performed again. +// +// If the return value is 0, source blocks have expected content and the command +// can be performed. + +static int LoadSrcTgtVersion3(CommandParameters* params, RangeSet** tgt, int* src_blocks, + int onehash, int* overlap) { + char* srchash = NULL; + char* tgthash = NULL; + int stash_exists = 0; + int rc = -1; + uint8_t* tgtbuffer = NULL; + + if (!params|| !tgt || !src_blocks || !overlap) { + goto v3out; + } + + srchash = strtok_r(NULL, " ", ¶ms->cpos); + + if (srchash == NULL) { + fprintf(stderr, "missing source hash\n"); + goto v3out; + } + + if (onehash) { + tgthash = srchash; + } else { + tgthash = strtok_r(NULL, " ", ¶ms->cpos); + + if (tgthash == NULL) { + fprintf(stderr, "missing target hash\n"); + goto v3out; + } + } + + if (LoadSrcTgtVersion2(¶ms->cpos, tgt, src_blocks, ¶ms->buffer, ¶ms->bufsize, + params->fd, params->stashbase, overlap) == -1) { + goto v3out; + } + + tgtbuffer = (uint8_t*) malloc((*tgt)->size * BLOCKSIZE); + + if (tgtbuffer == NULL) { + fprintf(stderr, "failed to allocate %d bytes\n", (*tgt)->size * BLOCKSIZE); + goto v3out; + } + + if (ReadBlocks(*tgt, tgtbuffer, params->fd) == -1) { + goto v3out; + } + + if (VerifyBlocks(tgthash, tgtbuffer, (*tgt)->size, 0) == 0) { + // Target blocks already have expected content, command should be skipped + rc = 1; + goto v3out; + } + + if (VerifyBlocks(srchash, params->buffer, *src_blocks, 1) == 0) { + // If source and target blocks overlap, stash the source blocks so we can + // resume from possible write errors + if (*overlap) { + fprintf(stderr, "stashing %d overlapping blocks to %s\n", *src_blocks, + srchash); + + if (WriteStash(params->stashbase, srchash, *src_blocks, params->buffer, 1, + &stash_exists) != 0) { + fprintf(stderr, "failed to stash overlapping source blocks\n"); + goto v3out; + } + + // Can be deleted when the write has completed + if (!stash_exists) { + params->freestash = srchash; + } + } + + // Source blocks have expected content, command can proceed + rc = 0; + goto v3out; + } + + if (*overlap && LoadStash(params->stashbase, srchash, 1, NULL, ¶ms->buffer, + ¶ms->bufsize, 1) == 0) { + // Overlapping source blocks were previously stashed, command can proceed. + // We are recovering from an interrupted command, so we don't know if the + // stash can safely be deleted after this command. + rc = 0; + goto v3out; + } + + // Valid source data not available, update cannot be resumed + fprintf(stderr, "partition has unexpected contents\n"); + params->isunresumable = 1; + +v3out: + if (tgtbuffer) { + free(tgtbuffer); + } + + return rc; +} + +static int PerformCommandMove(CommandParameters* params) { + int blocks = 0; + int overlap = 0; + int rc = -1; + int status = 0; + RangeSet* tgt = NULL; + + if (!params) { + goto pcmout; + } + + if (params->version == 1) { + status = LoadSrcTgtVersion1(¶ms->cpos, &tgt, &blocks, ¶ms->buffer, + ¶ms->bufsize, params->fd); + } else if (params->version == 2) { + status = LoadSrcTgtVersion2(¶ms->cpos, &tgt, &blocks, ¶ms->buffer, + ¶ms->bufsize, params->fd, params->stashbase, NULL); + } else if (params->version >= 3) { + status = LoadSrcTgtVersion3(params, &tgt, &blocks, 1, &overlap); + } + + if (status == -1) { + fprintf(stderr, "failed to read blocks for move\n"); + goto pcmout; + } + + if (status == 0) { + params->foundwrites = 1; + } else if (params->foundwrites) { + fprintf(stderr, "warning: commands executed out of order [%s]\n", params->cmdname); + } + + if (params->canwrite) { + if (status == 0) { + fprintf(stderr, " moving %d blocks\n", blocks); + + if (WriteBlocks(tgt, params->buffer, params->fd) == -1) { + goto pcmout; + } + } else { + fprintf(stderr, "skipping %d already moved blocks\n", blocks); + } + + } + + if (params->freestash) { + FreeStash(params->stashbase, params->freestash); + params->freestash = NULL; + } + + params->written += tgt->size; + rc = 0; + +pcmout: + if (tgt) { + free(tgt); + } + + return rc; +} + +static int PerformCommandStash(CommandParameters* params) { + if (!params) { + return -1; + } + + return SaveStash(params->stashbase, ¶ms->cpos, ¶ms->buffer, ¶ms->bufsize, + params->fd, (params->version >= 3), ¶ms->isunresumable); +} + +static int PerformCommandFree(CommandParameters* params) { + if (!params) { + return -1; + } + + if (params->createdstash || params->canwrite) { + return FreeStash(params->stashbase, params->cpos); + } + + return 0; +} + +static int PerformCommandZero(CommandParameters* params) { + char* range = NULL; + int i; + int j; + int rc = -1; + RangeSet* tgt = NULL; + + if (!params) { + goto pczout; + } + + range = strtok_r(NULL, " ", ¶ms->cpos); + + if (range == NULL) { + fprintf(stderr, "missing target blocks for zero\n"); + goto pczout; + } + + tgt = parse_range(range); + + fprintf(stderr, " zeroing %d blocks\n", tgt->size); + + allocate(BLOCKSIZE, ¶ms->buffer, ¶ms->bufsize); + memset(params->buffer, 0, BLOCKSIZE); + + if (params->canwrite) { + for (i = 0; i < tgt->count; ++i) { + if (!check_lseek(params->fd, (off64_t) tgt->pos[i * 2] * BLOCKSIZE, SEEK_SET)) { + goto pczout; + } + + for (j = tgt->pos[i * 2]; j < tgt->pos[i * 2 + 1]; ++j) { + if (write_all(params->fd, params->buffer, BLOCKSIZE) == -1) { + goto pczout; + } + } + } + } + + if (params->cmdname[0] == 'z') { + // Update only for the zero command, as the erase command will call + // this if DEBUG_ERASE is defined. + params->written += tgt->size; + } + + rc = 0; + +pczout: + if (tgt) { + free(tgt); + } + + return rc; +} + +static int PerformCommandNew(CommandParameters* params) { + char* range = NULL; + int rc = -1; + RangeSet* tgt = NULL; + RangeSinkState rss; + + if (!params) { + goto pcnout; + } + + range = strtok_r(NULL, " ", ¶ms->cpos); + + if (range == NULL) { + goto pcnout; + } + + tgt = parse_range(range); + + if (params->canwrite) { + fprintf(stderr, " writing %d blocks of new data\n", tgt->size); + + rss.fd = params->fd; + rss.tgt = tgt; + rss.p_block = 0; + rss.p_remain = (tgt->pos[1] - tgt->pos[0]) * BLOCKSIZE; + + if (!check_lseek(params->fd, (off64_t) tgt->pos[0] * BLOCKSIZE, SEEK_SET)) { + goto pcnout; + } + + pthread_mutex_lock(¶ms->nti.mu); + params->nti.rss = &rss; + pthread_cond_broadcast(¶ms->nti.cv); + + while (params->nti.rss) { + pthread_cond_wait(¶ms->nti.cv, ¶ms->nti.mu); + } + + pthread_mutex_unlock(¶ms->nti.mu); + } + + params->written += tgt->size; + rc = 0; + +pcnout: + if (tgt) { + free(tgt); + } + + return rc; +} + +static int PerformCommandDiff(CommandParameters* params) { + char* logparams = NULL; + char* value = NULL; + int blocks = 0; + int overlap = 0; + int rc = -1; + int status = 0; + RangeSet* tgt = NULL; + RangeSinkState rss; + size_t len = 0; + size_t offset = 0; + Value patch_value; + + if (!params) { + goto pcdout; + } + + logparams = strdup(params->cpos); + value = strtok_r(NULL, " ", ¶ms->cpos); + + if (value == NULL) { + fprintf(stderr, "missing patch offset for %s\n", params->cmdname); + goto pcdout; + } + + offset = strtoul(value, NULL, 0); + + value = strtok_r(NULL, " ", ¶ms->cpos); + + if (value == NULL) { + fprintf(stderr, "missing patch length for %s\n", params->cmdname); + goto pcdout; + } + + len = strtoul(value, NULL, 0); + + if (params->version == 1) { + status = LoadSrcTgtVersion1(¶ms->cpos, &tgt, &blocks, ¶ms->buffer, + ¶ms->bufsize, params->fd); + } else if (params->version == 2) { + status = LoadSrcTgtVersion2(¶ms->cpos, &tgt, &blocks, ¶ms->buffer, + ¶ms->bufsize, params->fd, params->stashbase, NULL); + } else if (params->version >= 3) { + status = LoadSrcTgtVersion3(params, &tgt, &blocks, 0, &overlap); + } + + if (status == -1) { + fprintf(stderr, "failed to read blocks for diff\n"); + goto pcdout; + } + + if (status == 0) { + params->foundwrites = 1; + } else if (params->foundwrites) { + fprintf(stderr, "warning: commands executed out of order [%s]\n", params->cmdname); + } + + if (params->canwrite) { + if (status == 0) { + fprintf(stderr, "patching %d blocks to %d\n", blocks, tgt->size); + + patch_value.type = VAL_BLOB; + patch_value.size = len; + patch_value.data = (char*) (params->patch_start + offset); + + rss.fd = params->fd; + rss.tgt = tgt; + rss.p_block = 0; + rss.p_remain = (tgt->pos[1] - tgt->pos[0]) * BLOCKSIZE; + + if (!check_lseek(params->fd, (off64_t) tgt->pos[0] * BLOCKSIZE, SEEK_SET)) { + goto pcdout; + } + + if (params->cmdname[0] == 'i') { // imgdiff + ApplyImagePatch(params->buffer, blocks * BLOCKSIZE, &patch_value, + &RangeSinkWrite, &rss, NULL, NULL); + } else { + ApplyBSDiffPatch(params->buffer, blocks * 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"); + } + } else { + fprintf(stderr, "skipping %d blocks already patched to %d [%s]\n", + blocks, tgt->size, logparams); + } + } + + if (params->freestash) { + FreeStash(params->stashbase, params->freestash); + params->freestash = NULL; + } + + params->written += tgt->size; + rc = 0; + +pcdout: + if (logparams) { + free(logparams); + } + + if (tgt) { + free(tgt); + } + + return rc; +} + +static int PerformCommandErase(CommandParameters* params) { + char* range = NULL; + int i; + int rc = -1; + RangeSet* tgt = NULL; + struct stat st; + uint64_t blocks[2]; + + if (DEBUG_ERASE) { + return PerformCommandZero(params); + } + + if (!params) { + goto pceout; + } + + if (fstat(params->fd, &st) == -1) { + fprintf(stderr, "failed to fstat device to erase: %s\n", strerror(errno)); + goto pceout; + } + + if (!S_ISBLK(st.st_mode)) { + fprintf(stderr, "not a block device; skipping erase\n"); + goto pceout; + } + + range = strtok_r(NULL, " ", ¶ms->cpos); + + if (range == NULL) { + fprintf(stderr, "missing target blocks for erase\n"); + goto pceout; + } + + tgt = parse_range(range); + + if (params->canwrite) { + fprintf(stderr, " erasing %d blocks\n", tgt->size); + + for (i = 0; i < tgt->count; ++i) { + // offset in bytes + blocks[0] = tgt->pos[i * 2] * (uint64_t) BLOCKSIZE; + // length in bytes + blocks[1] = (tgt->pos[i * 2 + 1] - tgt->pos[i * 2]) * (uint64_t) BLOCKSIZE; + + if (ioctl(params->fd, BLKDISCARD, &blocks) == -1) { + fprintf(stderr, "BLKDISCARD ioctl failed: %s\n", strerror(errno)); + goto pceout; + } + } + } + + rc = 0; + +pceout: + if (tgt) { + free(tgt); + } + + return rc; +} + +// Definitions for transfer list command functions +typedef int (*CommandFunction)(CommandParameters*); + +typedef struct { + const char* name; + CommandFunction f; +} Command; + +// CompareCommands and CompareCommandNames are for the hash table + +static int CompareCommands(const void* c1, const void* c2) { + return strcmp(((const Command*) c1)->name, ((const Command*) c2)->name); +} + +static int CompareCommandNames(const void* c1, const void* c2) { + return strcmp(((const Command*) c1)->name, (const char*) c2); +} + +// HashString is used to hash command names for the hash table + +static unsigned int HashString(const char *s) { + unsigned int hash = 0; + if (s) { + while (*s) { + hash = hash * 33 + *s++; + } + } + return hash; +} + +// 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) + +static Value* PerformBlockImageUpdate(const char* name, State* state, int argc, Expr* argv[], + const Command* commands, int cmdcount, int dryrun) { + + char* line = NULL; + char* linesave = NULL; + char* logcmd = NULL; + char* transfer_list = NULL; + CommandParameters params; + const Command* cmd = NULL; + const ZipEntry* new_entry = NULL; + const ZipEntry* patch_entry = NULL; + FILE* cmd_pipe = NULL; + HashTable* cmdht = NULL; + int i; + int res; + int rc = -1; + int stash_max_blocks = 0; + int total_blocks = 0; + pthread_attr_t attr; + unsigned int cmdhash; + UpdaterInfo* ui = NULL; + Value* blockdev_filename = NULL; + Value* new_data_fn = NULL; + Value* patch_data_fn = NULL; + Value* transfer_list_value = NULL; + ZipArchive* za = NULL; + + memset(¶ms, 0, sizeof(params)); + params.canwrite = !dryrun; + + fprintf(stderr, "performing %s\n", dryrun ? "verification" : "update"); + + if (ReadValueArgs(state, argv, 4, &blockdev_filename, &transfer_list_value, + &new_data_fn, &patch_data_fn) < 0) { + goto pbiudone; + } + + if (blockdev_filename->type != VAL_STRING) { + ErrorAbort(state, "blockdev_filename argument to %s must be string", name); + goto pbiudone; + } + if (transfer_list_value->type != VAL_BLOB) { + ErrorAbort(state, "transfer_list argument to %s must be blob", name); + goto pbiudone; + } + if (new_data_fn->type != VAL_STRING) { + ErrorAbort(state, "new_data_fn argument to %s must be string", name); + goto pbiudone; + } + if (patch_data_fn->type != VAL_STRING) { + ErrorAbort(state, "patch_data_fn argument to %s must be string", name); + goto pbiudone; + } + + ui = (UpdaterInfo*) state->cookie; + + if (ui == NULL) { + goto pbiudone; + } + + cmd_pipe = ui->cmd_pipe; + za = ui->package_zip; + + if (cmd_pipe == NULL || za == NULL) { + goto pbiudone; + } + + patch_entry = mzFindZipEntry(za, patch_data_fn->data); + + if (patch_entry == NULL) { + fprintf(stderr, "%s(): no file \"%s\" in package", name, patch_data_fn->data); + goto pbiudone; + } + + params.patch_start = ui->package_zip_addr + mzGetZipEntryOffset(patch_entry); + new_entry = mzFindZipEntry(za, new_data_fn->data); + + if (new_entry == NULL) { + fprintf(stderr, "%s(): no file \"%s\" in package", name, new_data_fn->data); + goto pbiudone; + } + + params.fd = TEMP_FAILURE_RETRY(open(blockdev_filename->data, O_RDWR)); + + if (params.fd == -1) { + fprintf(stderr, "open \"%s\" failed: %s\n", blockdev_filename->data, strerror(errno)); + goto pbiudone; + } + + if (params.canwrite) { + params.nti.za = za; + params.nti.entry = new_entry; + + pthread_mutex_init(¶ms.nti.mu, NULL); + pthread_cond_init(¶ms.nti.cv, NULL); + pthread_attr_init(&attr); + pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE); + + int error = pthread_create(¶ms.thread, &attr, unzip_new_data, ¶ms.nti); + if (error != 0) { + fprintf(stderr, "pthread_create failed: %s\n", strerror(error)); + goto pbiudone; + } + } + + // 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 = reinterpret_cast<char*>(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); + goto pbiudone; + } + + memcpy(transfer_list, transfer_list_value->data, transfer_list_value->size); + transfer_list[transfer_list_value->size] = '\0'; + + // First line in transfer list is the version number + line = strtok_r(transfer_list, "\n", &linesave); + params.version = strtol(line, NULL, 0); + + if (params.version < 1 || params.version > 3) { + fprintf(stderr, "unexpected transfer list version [%s]\n", line); + goto pbiudone; + } + + fprintf(stderr, "blockimg version is %d\n", params.version); + + // Second line in transfer list is the total number of blocks we expect to write + line = strtok_r(NULL, "\n", &linesave); + total_blocks = strtol(line, NULL, 0); + + if (total_blocks < 0) { + ErrorAbort(state, "unexpected block count [%s]\n", line); + goto pbiudone; + } else if (total_blocks == 0) { + rc = 0; + goto pbiudone; + } + + if (params.version >= 2) { + // Third line is how many stash entries are needed simultaneously + line = strtok_r(NULL, "\n", &linesave); + fprintf(stderr, "maximum stash entries %s\n", line); + + // Fourth line is the maximum number of blocks that will be stashed simultaneously + line = strtok_r(NULL, "\n", &linesave); + stash_max_blocks = strtol(line, NULL, 0); + + if (stash_max_blocks < 0) { + ErrorAbort(state, "unexpected maximum stash blocks [%s]\n", line); + goto pbiudone; + } + + if (stash_max_blocks >= 0) { + res = CreateStash(state, stash_max_blocks, blockdev_filename->data, + ¶ms.stashbase); + + if (res == -1) { + goto pbiudone; + } + + params.createdstash = res; + } + } + + // Build a hash table of the available commands + cmdht = mzHashTableCreate(cmdcount, NULL); + + for (i = 0; i < cmdcount; ++i) { + cmdhash = HashString(commands[i].name); + mzHashTableLookup(cmdht, cmdhash, (void*) &commands[i], CompareCommands, true); + } + + // Subsequent lines are all individual transfer commands + for (line = strtok_r(NULL, "\n", &linesave); line; + line = strtok_r(NULL, "\n", &linesave)) { + + logcmd = strdup(line); + params.cmdname = strtok_r(line, " ", ¶ms.cpos); + + if (params.cmdname == NULL) { + fprintf(stderr, "missing command [%s]\n", line); + goto pbiudone; + } + + cmdhash = HashString(params.cmdname); + cmd = (const Command*) mzHashTableLookup(cmdht, cmdhash, params.cmdname, + CompareCommandNames, false); + + if (cmd == NULL) { + fprintf(stderr, "unexpected command [%s]\n", params.cmdname); + goto pbiudone; + } + + if (cmd->f != NULL && cmd->f(¶ms) == -1) { + fprintf(stderr, "failed to execute command [%s]\n", + logcmd ? logcmd : params.cmdname); + goto pbiudone; + } + + if (logcmd) { + free(logcmd); + logcmd = NULL; + } + + if (params.canwrite) { + fprintf(cmd_pipe, "set_progress %.4f\n", (double) params.written / total_blocks); + fflush(cmd_pipe); + } + } + + if (params.canwrite) { + pthread_join(params.thread, NULL); + + fprintf(stderr, "wrote %d blocks; expected %d\n", params.written, total_blocks); + fprintf(stderr, "max alloc needed was %zu\n", params.bufsize); + + // Delete stash only after successfully completing the update, as it + // may contain blocks needed to complete the update later. + DeleteStash(params.stashbase); + } else { + fprintf(stderr, "verified partition contents; update may be resumed\n"); + } + + rc = 0; + +pbiudone: + if (params.fd != -1) { + if (fsync(params.fd) == -1) { + fprintf(stderr, "fsync failed: %s\n", strerror(errno)); + } + close(params.fd); + } + + if (logcmd) { + free(logcmd); + } + + if (cmdht) { + mzHashTableFree(cmdht); + } + + if (params.buffer) { + free(params.buffer); + } + + if (transfer_list) { + free(transfer_list); + } + + if (blockdev_filename) { + FreeValue(blockdev_filename); + } + + if (transfer_list_value) { + FreeValue(transfer_list_value); + } + + if (new_data_fn) { + FreeValue(new_data_fn); + } + + if (patch_data_fn) { + FreeValue(patch_data_fn); + } + + // Only delete the stash if the update cannot be resumed, or it's + // a verification run and we created the stash. + if (params.isunresumable || (!params.canwrite && params.createdstash)) { + DeleteStash(params.stashbase); + } + + if (params.stashbase) { + free(params.stashbase); + } + + return StringValue(rc == 0 ? strdup("t") : strdup("")); +} + +// 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 +// +// erase [rangeset] +// - mark the given blocks as empty +// +// move <...> +// bsdiff <patchstart> <patchlen> <...> +// imgdiff <patchstart> <patchlen> <...> +// - read the source blocks, apply a patch (or not in the +// case of move), write result to target blocks. bsdiff or +// imgdiff specifies the type of patch; move means no patch +// at all. +// +// The format of <...> differs between versions 1 and 2; +// see the LoadSrcTgtVersion{1,2}() functions for a +// description of what's expected. +// +// stash <stash_id> <src_range> +// - (version 2+ only) load the given source range and stash +// the data in the given slot of the stash table. +// +// 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. +// +// In version 2, the creator will guarantee that a given stash is +// loaded (with a stash command) before it's used in a +// move/bsdiff/imgdiff command. +// +// 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.) +// +// In version 3, commands that read data from the partition (i.e. +// move/bsdiff/imgdiff/stash) have one or more additional hashes +// before the range parameters, which are used to check if the +// command has already been completed and verify the integrity of +// the source data. + +Value* BlockImageVerifyFn(const char* name, State* state, int argc, Expr* argv[]) { + // Commands which are not tested are set to NULL to skip them completely + const Command commands[] = { + { "bsdiff", PerformCommandDiff }, + { "erase", NULL }, + { "free", PerformCommandFree }, + { "imgdiff", PerformCommandDiff }, + { "move", PerformCommandMove }, + { "new", NULL }, + { "stash", PerformCommandStash }, + { "zero", NULL } + }; + + // Perform a dry run without writing to test if an update can proceed + return PerformBlockImageUpdate(name, state, argc, argv, commands, + sizeof(commands) / sizeof(commands[0]), 1); +} + +Value* BlockImageUpdateFn(const char* name, State* state, int argc, Expr* argv[]) { + const Command commands[] = { + { "bsdiff", PerformCommandDiff }, + { "erase", PerformCommandErase }, + { "free", PerformCommandFree }, + { "imgdiff", PerformCommandDiff }, + { "move", PerformCommandMove }, + { "new", PerformCommandNew }, + { "stash", PerformCommandStash }, + { "zero", PerformCommandZero } + }; + + return PerformBlockImageUpdate(name, state, argc, argv, commands, + sizeof(commands) / sizeof(commands[0]), 0); +} + +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; + fd = open(blockdev_filename->data, O_RDWR); + if (fd < 0) { + ErrorAbort(state, "open \"%s\" failed: %s", blockdev_filename->data, strerror(errno)); + goto done; + } + + RangeSet* rs; + 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) { + if (!check_lseek(fd, (off64_t)rs->pos[i*2] * BLOCKSIZE, SEEK_SET)) { + ErrorAbort(state, "failed to seek %s: %s", blockdev_filename->data, + strerror(errno)); + goto done; + } + + for (j = rs->pos[i*2]; j < rs->pos[i*2+1]; ++j) { + if (read_all(fd, buffer, BLOCKSIZE) == -1) { + ErrorAbort(state, "failed to read %s: %s", blockdev_filename->data, + strerror(errno)); + goto done; + } + + 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_verify", BlockImageVerifyFn); + RegisterFunction("block_image_update", BlockImageUpdateFn); + RegisterFunction("range_sha1", RangeSha1Fn); +} |