1 files changed, 443 insertions, 0 deletions
diff --git a/package/system/fwtool/src/fwtool.c b/package/system/fwtool/src/fwtool.c
new file mode 100644
index 0000000000..e77b8b58e1
--- /dev/null
+++ b/package/system/fwtool/src/fwtool.c
@@ -0,0 +1,443 @@
+/*
+ * Copyright (C) 2016 Felix Fietkau <nbd@nbd.name>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+#include <sys/types.h>
+#include <stdio.h>
+#include <getopt.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "fwimage.h"
+#include "utils.h"
+#include "crc32.h"
+
+#define METADATA_MAXLEN		30 * 1024
+#define SIGNATURE_MAXLEN	1 * 1024
+
+#define BUFLEN			(METADATA_MAXLEN + SIGNATURE_MAXLEN + 1024)
+
+enum {
+	MODE_DEFAULT = -1,
+	MODE_EXTRACT = 0,
+	MODE_APPEND = 1,
+};
+
+struct data_buf {
+	char *cur;
+	char *prev;
+	int cur_len;
+	int file_len;
+};
+
+static FILE *signature_file, *metadata_file, *firmware_file;
+static int file_mode = MODE_DEFAULT;
+static bool truncate_file;
+static bool quiet = false;
+
+static uint32_t crc_table[256];
+
+#define msg(...)					\
+	do {						\
+		if (!quiet)				\
+			fprintf(stderr, __VA_ARGS__);	\
+	} while (0)
+
+static int
+usage(const char *progname)
+{
+	fprintf(stderr, "Usage: %s <options> <firmware>\n"
+		"\n"
+		"Options:\n"
+		"  -S <file>:		Append signature file to firmware image\n"
+		"  -I <file>:		Append metadata file to firmware image\n"
+		"  -s <file>:		Extract signature file from firmware image\n"
+		"  -i <file>:		Extract metadata file from firmware image\n"
+		"  -t:			Remove extracted chunks from firmare image (using -s, -i)\n"
+		"  -q:			Quiet (suppress error messages)\n"
+		"\n", progname);
+	return 1;
+}
+
+static FILE *
+open_file(const char *name, bool write)
+{
+	FILE *ret;
+
+	if (!strcmp(name, "-"))
+		return write ? stdout : stdin;
+
+	ret = fopen(name, write ? "w" : "r+");
+	if (!ret && !write)
+		ret = fopen(name, "r");
+
+	return ret;
+}
+
+static int
+set_file(FILE **file, const char *name, int mode)
+{
+	if (file_mode < 0)
+		file_mode = mode;
+	else if (file_mode != mode) {
+		msg("Error: mixing appending and extracting data is not supported\n");
+		return 1;
+	}
+
+	if (*file) {
+		msg("Error: the same append/extract option cannot be used multiple times\n");
+		return 1;
+	}
+
+	*file = open_file(name, mode == MODE_EXTRACT);
+	return !*file;
+}
+
+static void
+trailer_update_crc(struct fwimage_trailer *tr, void *buf, int len)
+{
+	tr->crc32 = cpu_to_be32(crc32_block(be32_to_cpu(tr->crc32), buf, len, crc_table));
+}
+
+static int
+append_data(FILE *in, FILE *out, struct fwimage_trailer *tr, int maxlen)
+{
+	while (1) {
+		char buf[512];
+		int len;
+
+		len = fread(buf, 1, sizeof(buf), in);
+		if (!len)
+			break;
+
+		maxlen -= len;
+		if (maxlen < 0)
+			return 1;
+
+		tr->size += len;
+		trailer_update_crc(tr, buf, len);
+		fwrite(buf, len, 1, out);
+	}
+
+	return 0;
+}
+
+static void
+append_trailer(FILE *out, struct fwimage_trailer *tr)
+{
+	tr->size = cpu_to_be32(tr->size);
+	fwrite(tr, sizeof(*tr), 1, out);
+	trailer_update_crc(tr, tr, sizeof(*tr));
+}
+
+static int
+add_metadata(struct fwimage_trailer *tr)
+{
+	struct fwimage_header hdr = {};
+
+	tr->type = FWIMAGE_INFO;
+	tr->size = sizeof(hdr) + sizeof(*tr);
+
+	trailer_update_crc(tr, &hdr, sizeof(hdr));
+	fwrite(&hdr, sizeof(hdr), 1, firmware_file);
+
+	if (append_data(metadata_file, firmware_file, tr, METADATA_MAXLEN))
+		return 1;
+
+	append_trailer(firmware_file, tr);
+
+	return 0;
+}
+
+static int
+add_signature(struct fwimage_trailer *tr)
+{
+	if (!signature_file)
+		return 0;
+
+	tr->type = FWIMAGE_SIGNATURE;
+	tr->size = sizeof(*tr);
+
+	if (append_data(signature_file, firmware_file, tr, SIGNATURE_MAXLEN))
+		return 1;
+
+	append_trailer(firmware_file, tr);
+
+	return 0;
+}
+
+static int
+add_data(const char *name)
+{
+	struct fwimage_trailer tr = {
+		.magic = cpu_to_be32(FWIMAGE_MAGIC),
+		.crc32 = ~0,
+	};
+	int file_len = 0;
+	int ret = 0;
+
+	firmware_file = fopen(name, "r+");
+	if (!firmware_file) {
+		msg("Failed to open firmware file\n");
+		return 1;
+	}
+
+	while (1) {
+		char buf[512];
+		int len;
+
+		len = fread(buf, 1, sizeof(buf), firmware_file);
+		if (!len)
+			break;
+
+		file_len += len;
+		trailer_update_crc(&tr, buf, len);
+	}
+
+	if (metadata_file)
+		ret = add_metadata(&tr);
+	else if (signature_file)
+		ret = add_signature(&tr);
+
+	if (ret) {
+		fflush(firmware_file);
+		ftruncate(fileno(firmware_file), file_len);
+	}
+
+	return ret;
+}
+
+static void
+remove_tail(struct data_buf *dbuf, int len)
+{
+	dbuf->cur_len -= len;
+	dbuf->file_len -= len;
+
+	if (dbuf->cur_len)
+		return;
+
+	free(dbuf->cur);
+	dbuf->cur = dbuf->prev;
+	dbuf->prev = NULL;
+	dbuf->cur_len = BUFLEN;
+}
+
+static int
+extract_tail(struct data_buf *dbuf, void *dest, int len)
+{
+	int cur_len = dbuf->cur_len;
+
+	if (!dbuf->cur)
+		return 1;
+
+	if (cur_len >= len)
+		cur_len = len;
+
+	memcpy(dest + (len - cur_len), dbuf->cur + dbuf->cur_len - cur_len, cur_len);
+	remove_tail(dbuf, cur_len);
+
+	cur_len = len - cur_len;
+	if (cur_len && !dbuf->cur)
+		return 1;
+
+	memcpy(dest, dbuf->cur + dbuf->cur_len - cur_len, cur_len);
+	remove_tail(dbuf, cur_len);
+
+	return 0;
+}
+
+static uint32_t
+tail_crc32(struct data_buf *dbuf, uint32_t crc32)
+{
+	if (dbuf->prev)
+		crc32 = crc32_block(crc32, dbuf->prev, BUFLEN, crc_table);
+
+	return crc32_block(crc32, dbuf->cur, dbuf->cur_len, crc_table);
+}
+
+static int
+validate_metadata(struct fwimage_header *hdr, int data_len)
+{
+	 if (hdr->version != 0)
+		 return 1;
+	 return 0;
+}
+
+static int
+extract_data(const char *name)
+{
+	struct fwimage_header *hdr;
+	struct fwimage_trailer tr;
+	struct data_buf dbuf = {};
+	uint32_t crc32 = ~0;
+	int ret = 1;
+	void *buf;
+
+	firmware_file = open_file(name, false);
+	if (!firmware_file) {
+		msg("Failed to open firmware file\n");
+		return 1;
+	}
+
+	if (truncate_file && firmware_file == stdin) {
+		msg("Cannot truncate file when reading from stdin\n");
+		return 1;
+	}
+
+	buf = malloc(BUFLEN);
+	if (!buf)
+		return 1;
+
+	do {
+		char *tmp = dbuf.cur;
+
+		dbuf.cur = dbuf.prev;
+		dbuf.prev = tmp;
+
+		if (dbuf.cur)
+			crc32 = crc32_block(crc32, dbuf.cur, BUFLEN, crc_table);
+		else
+			dbuf.cur = malloc(BUFLEN);
+
+		if (!dbuf.cur)
+			goto out;
+
+		dbuf.cur_len = fread(dbuf.cur, 1, BUFLEN, firmware_file);
+		dbuf.file_len += dbuf.cur_len;
+	} while (dbuf.cur_len == BUFLEN);
+
+	while (1) {
+		int data_len;
+
+		if (extract_tail(&dbuf, &tr, sizeof(tr)))
+			break;
+
+		data_len = be32_to_cpu(tr.size) - sizeof(tr);
+		if (tr.magic != cpu_to_be32(FWIMAGE_MAGIC)) {
+			msg("Data not found\n");
+			break;
+		}
+
+		if (be32_to_cpu(tr.crc32) != tail_crc32(&dbuf, crc32)) {
+			msg("CRC error\n");
+			break;
+		}
+
+		if (data_len > BUFLEN) {
+			msg("Size error\n");
+			break;
+		}
+
+		extract_tail(&dbuf, buf, data_len);
+
+		if (tr.type == FWIMAGE_SIGNATURE) {
+			if (!signature_file)
+				continue;
+			fwrite(buf, data_len, 1, signature_file);
+			ret = 0;
+			break;
+		} else if (tr.type == FWIMAGE_INFO) {
+			if (!metadata_file)
+				break;
+
+			hdr = buf;
+			data_len -= sizeof(*hdr);
+			if (validate_metadata(hdr, data_len))
+				continue;
+
+			fwrite(hdr + 1, data_len, 1, metadata_file);
+			ret = 0;
+			break;
+		} else {
+			continue;
+		}
+	}
+
+	if (!ret && truncate_file)
+		ftruncate(fileno(firmware_file), dbuf.file_len);
+
+out:
+	free(buf);
+	free(dbuf.cur);
+	free(dbuf.prev);
+	return ret;
+}
+
+static void cleanup(void)
+{
+	if (signature_file)
+		fclose(signature_file);
+	if (metadata_file)
+		fclose(metadata_file);
+	if (firmware_file)
+		fclose(firmware_file);
+}
+
+int main(int argc, char **argv)
+{
+	const char *progname = argv[0];
+	int ret, ch;
+
+	crc32_filltable(crc_table);
+
+	while ((ch = getopt(argc, argv, "i:I:qs:S:t")) != -1) {
+		ret = 0;
+		switch(ch) {
+		case 'S':
+			ret = set_file(&signature_file, optarg, MODE_APPEND);
+			break;
+		case 'I':
+			ret = set_file(&metadata_file, optarg, MODE_APPEND);
+			break;
+		case 's':
+			ret = set_file(&signature_file, optarg, MODE_EXTRACT);
+			break;
+		case 'i':
+			ret = set_file(&metadata_file, optarg, MODE_EXTRACT);
+			break;
+		case 't':
+			truncate_file = true;
+			break;
+		case 'q':
+			quiet = true;
+			break;
+		}
+
+		if (ret)
+			goto out;
+	}
+
+	if (optind >= argc) {
+		ret = usage(progname);
+		goto out;
+	}
+
+	if (file_mode == MODE_DEFAULT) {
+		ret = usage(progname);
+		goto out;
+	}
+
+	if (signature_file && metadata_file) {
+		msg("Cannot append/extract metadata and signature in one run\n");
+		return 1;
+	}
+
+	if (file_mode)
+		ret = add_data(argv[optind]);
+	else
+		ret = extract_data(argv[optind]);
+
+out:
+	cleanup();
+	return ret;
+}