/*
* Copyright (C) 2015 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.
*/
extern "C" {
#include <fec.h>
}
#undef NDEBUG
#include <assert.h>
#include <errno.h>
#include <getopt.h>
#include <fcntl.h>
#include <pthread.h>
#include <stdlib.h>
#include <string.h>
#include <android-base/file.h>
#include "image.h"
enum {
MODE_ENCODE,
MODE_DECODE,
MODE_PRINTSIZE,
MODE_GETECCSTART,
MODE_GETVERITYSTART
};
static void encode_rs(struct image_proc_ctx *ctx)
{
struct image *fcx = ctx->ctx;
int j;
uint8_t data[fcx->rs_n];
uint64_t i;
for (i = ctx->start; i < ctx->end; i += fcx->rs_n) {
for (j = 0; j < fcx->rs_n; ++j) {
data[j] = image_get_interleaved_byte(i + j, fcx);
}
encode_rs_char(ctx->rs, data, &fcx->fec[ctx->fec_pos]);
ctx->fec_pos += fcx->roots;
}
}
static void decode_rs(struct image_proc_ctx *ctx)
{
struct image *fcx = ctx->ctx;
int j, rv;
uint8_t data[fcx->rs_n + fcx->roots];
uint64_t i;
assert(sizeof(data) == FEC_RSM);
for (i = ctx->start; i < ctx->end; i += fcx->rs_n) {
for (j = 0; j < fcx->rs_n; ++j) {
data[j] = image_get_interleaved_byte(i + j, fcx);
}
memcpy(&data[fcx->rs_n], &fcx->fec[ctx->fec_pos], fcx->roots);
rv = decode_rs_char(ctx->rs, data, NULL, 0);
if (rv < 0) {
FATAL("failed to recover [%" PRIu64 ", %" PRIu64 ")\n",
i, i + fcx->rs_n);
} else if (rv > 0) {
/* copy corrected data to output */
for (j = 0; j < fcx->rs_n; ++j) {
image_set_interleaved_byte(i + j, fcx, data[j]);
}
ctx->rv += rv;
}
ctx->fec_pos += fcx->roots;
}
}
static int usage()
{
printf("fec: a tool for encoding and decoding files using RS(255, N).\n"
"\n"
"usage: fec <mode> [ <options> ] [ <data> <fec> [ <output> ] ]\n"
"mode:\n"
" -e --encode encode (default)\n"
" -d --decode decode\n"
" -s, --print-fec-size=<data size> print FEC size\n"
" -E, --get-ecc-start=data print ECC offset in data\n"
" -V, --get-verity-start=data print verity offset\n"
"options:\n"
" -h show this help\n"
" -v enable verbose logging\n"
" -r, --roots=<bytes> number of parity bytes\n"
" -j, --threads=<threads> number of threads to use\n"
" -S treat data as a sparse file\n"
"encoding options:\n"
" -p, --padding=<bytes> add padding after ECC data\n"
"decoding options:\n"
" -i, --inplace correct <data> in place\n"
);
return 1;
}
static uint64_t parse_arg(const char *arg, const char *name, uint64_t maxval)
{
char* endptr;
errno = 0;
unsigned long long int value = strtoull(arg, &endptr, 0);
if (arg[0] == '\0' || *endptr != '\0' ||
(errno == ERANGE && value == ULLONG_MAX)) {
FATAL("invalid value of %s\n", name);
}
if (value > maxval) {
FATAL("value of roots too large (max. %" PRIu64 ")\n", maxval);
}
return (uint64_t)value;
}
static int print_size(image& ctx)
{
/* output size including header */
printf("%" PRIu64 "\n", fec_ecc_get_size(ctx.inp_size, ctx.roots));
return 0;
}
static int get_start(int mode, const std::string& filename)
{
fec::io fh(filename, O_RDONLY, FEC_VERITY_DISABLE);
if (!fh) {
FATAL("failed to open input\n");
}
if (mode == MODE_GETECCSTART) {
fec_ecc_metadata data;
if (!fh.get_ecc_metadata(data)) {
FATAL("no ecc data\n");
}
printf("%" PRIu64 "\n", data.start);
} else {
fec_verity_metadata data;
if (!fh.get_verity_metadata(data)) {
FATAL("no verity data\n");
}
printf("%" PRIu64 "\n", data.data_size);
}
return 0;
}
static int encode(image& ctx, const std::vector<std::string>& inp_filenames,
const std::string& fec_filename)
{
if (ctx.inplace) {
FATAL("invalid parameters: inplace can only used when decoding\n");
}
if (!image_load(inp_filenames, &ctx)) {
FATAL("failed to read input\n");
}
if (!image_ecc_new(fec_filename, &ctx)) {
FATAL("failed to allocate ecc\n");
}
INFO("encoding RS(255, %d) to '%s' for input files:\n", ctx.rs_n,
fec_filename.c_str());
size_t n = 1;
for (const auto& fn : inp_filenames) {
INFO("\t%zu: '%s'\n", n++, fn.c_str());
}
if (ctx.verbose) {
INFO("\traw fec size: %u\n", ctx.fec_size);
INFO("\tblocks: %" PRIu64 "\n", ctx.blocks);
INFO("\trounds: %" PRIu64 "\n", ctx.rounds);
}
if (!image_process(encode_rs, &ctx)) {
FATAL("failed to process input\n");
}
if (!image_ecc_save(&ctx)) {
FATAL("failed to write output\n");
}
image_free(&ctx);
return 0;
}
static int decode(image& ctx, const std::vector<std::string>& inp_filenames,
const std::string& fec_filename, std::string& out_filename)
{
const std::string& inp_filename = inp_filenames.front();
if (ctx.inplace && ctx.sparse) {
FATAL("invalid parameters: inplace cannot be used with sparse "
"files\n");
}
if (ctx.padding) {
FATAL("invalid parameters: padding is only relevant when encoding\n");
}
if (!image_ecc_load(fec_filename, &ctx) ||
!image_load(inp_filenames, &ctx)) {
FATAL("failed to read input\n");
}
if (ctx.inplace) {
INFO("correcting '%s' using RS(255, %d) from '%s'\n",
inp_filename.c_str(), ctx.rs_n, fec_filename.c_str());
out_filename = inp_filename;
} else {
INFO("decoding '%s' to '%s' using RS(255, %d) from '%s'\n",
inp_filename.c_str(),
out_filename.empty() ? out_filename.c_str() : "<none>", ctx.rs_n,
fec_filename.c_str());
}
if (ctx.verbose) {
INFO("\traw fec size: %u\n", ctx.fec_size);
INFO("\tblocks: %" PRIu64 "\n", ctx.blocks);
INFO("\trounds: %" PRIu64 "\n", ctx.rounds);
}
if (!image_process(decode_rs, &ctx)) {
FATAL("failed to process input\n");
}
if (ctx.rv) {
INFO("corrected %" PRIu64 " errors\n", ctx.rv);
} else {
INFO("no errors found\n");
}
if (!out_filename.empty() && !image_save(out_filename, &ctx)) {
FATAL("failed to write output\n");
}
image_free(&ctx);
return 0;
}
int main(int argc, char **argv)
{
std::string fec_filename;
std::string out_filename;
std::vector<std::string> inp_filenames;
int mode = MODE_ENCODE;
image ctx;
image_init(&ctx);
ctx.roots = FEC_DEFAULT_ROOTS;
while (1) {
const static struct option long_options[] = {
{"help", no_argument, 0, 'h'},
{"encode", no_argument, 0, 'e'},
{"decode", no_argument, 0, 'd'},
{"sparse", no_argument, 0, 'S'},
{"roots", required_argument, 0, 'r'},
{"inplace", no_argument, 0, 'i'},
{"threads", required_argument, 0, 'j'},
{"print-fec-size", required_argument, 0, 's'},
{"get-ecc-start", required_argument, 0, 'E'},
{"get-verity-start", required_argument, 0, 'V'},
{"padding", required_argument, 0, 'p'},
{"verbose", no_argument, 0, 'v'},
{NULL, 0, 0, 0}
};
int c = getopt_long(argc, argv, "hedSr:ij:s:E:V:p:v", long_options, NULL);
if (c < 0) {
break;
}
switch (c) {
case 'h':
return usage();
case 'S':
ctx.sparse = true;
break;
case 'e':
if (mode != MODE_ENCODE) {
return usage();
}
break;
case 'd':
if (mode != MODE_ENCODE) {
return usage();
}
mode = MODE_DECODE;
break;
case 'r':
ctx.roots = (int)parse_arg(optarg, "roots", FEC_RSM);
break;
case 'i':
ctx.inplace = true;
break;
case 'j':
ctx.threads = (int)parse_arg(optarg, "threads", IMAGE_MAX_THREADS);
break;
case 's':
if (mode != MODE_ENCODE) {
return usage();
}
mode = MODE_PRINTSIZE;
ctx.inp_size = parse_arg(optarg, "print-fec-size", UINT64_MAX);
break;
case 'E':
if (mode != MODE_ENCODE) {
return usage();
}
mode = MODE_GETECCSTART;
inp_filenames.push_back(optarg);
break;
case 'V':
if (mode != MODE_ENCODE) {
return usage();
}
mode = MODE_GETVERITYSTART;
inp_filenames.push_back(optarg);
break;
case 'p':
ctx.padding = (uint32_t)parse_arg(optarg, "padding", UINT32_MAX);
if (ctx.padding % FEC_BLOCKSIZE) {
FATAL("padding must be multiple of %u\n", FEC_BLOCKSIZE);
}
break;
case 'v':
ctx.verbose = true;
break;
case '?':
return usage();
default:
abort();
}
}
argc -= optind;
argv += optind;
assert(ctx.roots > 0 && ctx.roots < FEC_RSM);
/* check for input / output parameters */
if (mode == MODE_ENCODE) {
/* allow multiple input files */
for (int i = 0; i < (argc - 1); ++i) {
inp_filenames.push_back(argv[i]);
}
if (inp_filenames.empty()) {
return usage();
}
/* the last one is the output file */
fec_filename = argv[argc - 1];
} else if (mode == MODE_DECODE) {
if (argc < 2 || argc > 3) {
return usage();
} else if (argc == 3) {
if (ctx.inplace) {
return usage();
}
out_filename = argv[2];
}
inp_filenames.push_back(argv[0]);
fec_filename = argv[1];
}
switch (mode) {
case MODE_PRINTSIZE:
return print_size(ctx);
case MODE_GETECCSTART:
case MODE_GETVERITYSTART:
return get_start(mode, inp_filenames.front());
case MODE_ENCODE:
return encode(ctx, inp_filenames, fec_filename);
case MODE_DECODE:
return decode(ctx, inp_filenames, fec_filename, out_filename);
default:
abort();
}
return 1;
}