blob: 6060ac28bc35a6822f6e62c324a408ce03e65d9c [file] [log] [blame]
/*
* 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 %zu 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;
}
// 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 void LoadSrcTgtVersion1(char* wordsave, RangeSet** tgt, int* src_blocks,
uint8_t** buffer, size_t* buffer_alloc, int fd) {
char* word;
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);
size_t p = 0;
int i;
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;
}
*src_blocks = src->size;
free(src);
}
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 taken from stash_table
// and free()'d after being used.
static void LoadSrcTgtVersion2(char* wordsave, RangeSet** tgt, int* src_blocks,
uint8_t** buffer, size_t* buffer_alloc, int fd,
uint8_t** stash_table) {
char* word;
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);
size_t p = 0;
int i;
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;
}
free(src);
word = strtok_r(NULL, " ", &wordsave);
if (word == NULL) {
// no stashes, only source range
return;
}
RangeSet* locs = parse_range(word);
MoveRange(*buffer, locs, *buffer);
}
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.
char* colonsave = NULL;
char* colon = strtok_r(word, ":", &colonsave);
int stash_id = strtol(colon, NULL, 0);
colon = strtok_r(NULL, ":", &colonsave);
RangeSet* locs = parse_range(colon);
MoveRange(*buffer, locs, stash_table[stash_id]);
free(stash_table[stash_id]);
stash_table[stash_id] = NULL;
free(locs);
}
}
// 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
//
// 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.)
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);
int version;
// first line in transfer list is the version number; currently
// there's only version 1.
if (strcmp(line, "1") == 0) {
version = 1;
} else if (strcmp(line, "2") == 0) {
version = 2;
} else {
ErrorAbort(state, "unexpected transfer list version [%s]\n", line);
goto done;
}
printf("blockimg version is %d\n", version);
// 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** stash_table = NULL;
if (version >= 2) {
// Next line is how many stash entries are needed simultaneously.
line = strtok_r(NULL, "\n", &linesave);
int stash_entries = strtol(line, NULL, 0);
stash_table = (uint8_t**) calloc(stash_entries, sizeof(uint8_t*));
if (stash_table == NULL) {
fprintf(stderr, "failed to allocate %d-entry stash table\n", stash_entries);
exit(1);
}
// Next line is the maximum number of blocks that will be
// stashed simultaneously. This could be used to verify that
// enough memory or scratch disk space is available.
line = strtok_r(NULL, "\n", &linesave);
int stash_max_blocks = strtol(line, NULL, 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) {
RangeSet* tgt;
int src_blocks;
if (version == 1) {
LoadSrcTgtVersion1(wordsave, &tgt, &src_blocks,
&buffer, &buffer_alloc, fd);
} else if (version == 2) {
LoadSrcTgtVersion2(wordsave, &tgt, &src_blocks,
&buffer, &buffer_alloc, fd, stash_table);
}
printf(" moving %d blocks\n", src_blocks);
size_t 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(tgt);
} else if (strcmp("stash", style) == 0) {
word = strtok_r(NULL, " ", &wordsave);
int stash_id = strtol(word, NULL, 0);
int src_blocks;
size_t stash_alloc = 0;
// Even though the "stash" style only appears in version
// 2, the version 1 source loader happens to do exactly
// what we want to read data into the stash_table.
LoadSrcTgtVersion1(wordsave, NULL, &src_blocks,
stash_table + stash_id, &stash_alloc, fd);
} 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);
RangeSet* tgt;
int src_blocks;
if (version == 1) {
LoadSrcTgtVersion1(wordsave, &tgt, &src_blocks,
&buffer, &buffer_alloc, fd);
} else if (version == 2) {
LoadSrcTgtVersion2(wordsave, &tgt, &src_blocks,
&buffer, &buffer_alloc, fd, stash_table);
}
printf(" patching %d blocks to %d\n", src_blocks, tgt->size);
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);
int ret;
if (style[0] == 'i') { // imgdiff
ret = ApplyImagePatch(buffer, src_blocks * BLOCKSIZE,
&patch_value,
&RangeSinkWrite, &rss, NULL, NULL);
} else {
ret = ApplyBSDiffPatch(buffer, src_blocks * BLOCKSIZE,
&patch_value, 0,
&RangeSinkWrite, &rss, NULL);
}
if (ret != 0) {
ErrorAbort(state, "patch failed\n");
goto done;
}
// We expect the output of the patcher to fill the tgt ranges exactly.
if (rss.p_block != tgt->count || rss.p_remain != 0) {
ErrorAbort(state, "range sink underrun?\n");
goto done;
}
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 (!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) {
ErrorAbort(state, " blkdiscard failed: %s\n", strerror(errno));
goto done;
}
}
free(tgt);
} else {
printf(" ignoring erase (not block device)\n");
}
} else {
ErrorAbort(state, "unknown transfer style \"%s\"\n", style);
goto done;
}
}
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);
if (success) {
return StringValue(strdup("t"));
} else {
// NULL will be passed to its caller at Evaluate() and abort the OTA
// process.
return NULL;
}
}
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 NULL;
} else {
return StringValue(PrintSha1(digest));
}
}
void RegisterBlockImageFunctions() {
RegisterFunction("block_image_update", BlockImageUpdateFn);
RegisterFunction("range_sha1", RangeSha1Fn);
}