+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * zytrx - add header to images for ZyXEL NR7101
+ *
+ * Based on add_header.c - partially based on OpenWrt's
+ * motorola-bin.c
+ *
+ * Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
+ * Gabor Juhos <juhosg@openwrt.org>
+ * Copyright (C) 2021 Bjørn Mork <bjorn@mork.no>
+
+ * 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.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <unistd.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <string.h>
+#include <netinet/in.h>
+#include <inttypes.h>
+
+#define BPB 8 /* bits/byte */
+
+static uint32_t crc32[1<<BPB];
+
+static void init_crc32(void)
+{
+ const uint32_t poly = ntohl(0x2083b8ed);
+ int n;
+
+ for (n = 0; n < 1<<BPB; n++) {
+ uint32_t crc = n;
+ int bit;
+
+ for (bit = 0; bit < BPB; bit++)
+ crc = (crc & 1) ? (poly ^ (crc >> 1)) : (crc >> 1);
+ crc32[n] = crc;
+ }
+}
+
+static uint32_t crc32buf(const unsigned char *buf, size_t len)
+{
+ uint32_t crc = 0xFFFFFFFF;
+
+ for (; len; len--, buf++)
+ crc = crc32[(uint8_t)crc ^ *buf] ^ (crc >> BPB);
+ return ~crc;
+}
+
+/* HDR0 reversed, to be stored as BE */
+#define MAGIC 0x30524448 /* HDR0 reversed, to be stored as BE */
+
+/* All numbers are stored as BE */
+struct zytrx_t {
+ uint32_t magic;
+ uint32_t len_h; /* Length of this header */
+ uint32_t len_t; /* Total length of file */
+ uint32_t crc32_p; /* Bit inverted 32-bit CRC of image payload */
+ uint8_t verInt[32]; /* String "5.0.0.0\n" zero padded */
+ uint8_t verExt[32]; /* String "\n" zero padded */
+ uint32_t len_p; /* Length of image payload */
+ uint8_t pad1[12]; /* zero padding(?) */
+ uint8_t code[164]; /* string "3 6035 122 0\n" zero padded */
+ uint8_t chipid[8]; /* string "MT7621A" zero padded */
+ uint8_t boardid[16]; /* string "NR7101" zero padded */
+ uint32_t modelid; /* modelid as 4 BCD digits: 0x07010001 */
+ uint8_t pad2[8]; /* zero padding(?) */
+ uint8_t swVersionInt[32]; /* ZyXEL version string: "1.00(ABUV.0)D0" zero padded */
+ uint8_t swVersionExt[32]; /* identical to swVersionInt */
+ uint8_t pad4[4]; /* zero padding(?) */
+ uint32_t kernelChksum; /* no idea how this is computed - reported but not validated */
+ uint8_t pad5[4]; /* zero padding(?) */
+ uint32_t crc32_h; /* Bit inverted 32-bit CRC of this header payload */
+ uint8_t pad6[4]; /* zero padding(?) */
+};
+
+/* static?() field values of unknown meaning - maybe ove to board
+ * table when we know the significance
+ */
+#define VER_INT "5.0.0.0\n"
+#define VER_EXT "\n"
+#define CODE "3 6035 122 0\n"
+#define KERNELCHKSUM 0x12345678
+
+/* table of supported devices using this header format */
+static struct board_t {
+ uint8_t chipid[8];
+ uint8_t boardid[16];
+ uint32_t modelid;
+} boards[] = {
+ { "MT7621A", "NR7101", 0x07010001 },
+ {}
+};
+
+static int find_board(struct zytrx_t *h, char *board)
+{
+ struct board_t *p;
+
+ for (p = boards; p->modelid; p++) {
+ if (strncmp((const char *)p->boardid, board, sizeof(p->boardid)))
+ continue;
+ memcpy(h->chipid, p->chipid, sizeof(h->chipid));
+ memcpy(h->boardid, p->boardid, sizeof(h->boardid));
+ h->modelid = htonl(p->modelid);
+ return 0;
+ }
+ return -1;
+}
+
+static void usage(const char *name)
+{
+ struct board_t *p;
+
+ fprintf(stderr, "Usage:\n");
+ fprintf(stderr, " %s -B <board> -v <versionstr> -i <file> [-o <outputfile>]\n\n", name);
+ fprintf(stderr, "Supported <board> values:\n");
+ for (p = boards; p->modelid; p++)
+ fprintf(stderr, "\t%-12s\n", p->boardid);
+ fprintf(stderr, "\nExample:\n");
+ fprintf(stderr, " %s -B %s -v foobar-1.0 -i my.img -o out.img\n\n", name,
+ boards[0].boardid);
+ exit(EXIT_FAILURE);
+}
+
+static void errexit(const char *msg)
+{
+ fprintf(stderr, "ERR: %s: %s\n", msg, errno ? strerror(errno) : "unknown");
+ exit(EXIT_FAILURE);
+}
+
+static void *map_input(const char *name, size_t *len)
+{
+ struct stat stat;
+ void *mapped;
+ int fd;
+
+ fd = open(name, O_RDONLY);
+ if (fd < 0)
+ return NULL;
+ if (fstat(fd, &stat) < 0) {
+ close(fd);
+ return NULL;
+ }
+ *len = stat.st_size;
+ mapped = mmap(NULL, stat.st_size, PROT_READ, MAP_SHARED, fd, 0);
+ if (close(fd) < 0)
+ return NULL;
+ return mapped;
+}
+
+int main(int argc, char **argv)
+{
+ int c, fdout = STDOUT_FILENO;
+ void *input_file = NULL;
+ size_t file_len, len;
+ uint32_t crc;
+ struct zytrx_t h = {
+ .magic = htonl(MAGIC),
+ .len_h = htonl(sizeof(h)),
+ .verInt = VER_INT,
+ .verExt = VER_EXT,
+ .code = CODE,
+ .kernelChksum = htonl(KERNELCHKSUM),
+ };
+
+ while ((c = getopt(argc, argv, "B:v:i:o:")) != -1) {
+ switch (c) {
+ case 'B':
+ if (find_board(&h, optarg) < 0)
+ errexit("unsupported board");
+ break;
+ case 'v':
+ len = strlen(optarg);
+ if (len > sizeof(h.swVersionInt))
+ errexit("version string too long");
+ memcpy(h.swVersionInt, optarg, len);
+ memcpy(h.swVersionExt, optarg, len);
+ break;
+ case 'i':
+ input_file = map_input(optarg, &file_len);
+ if (!input_file)
+ errexit(optarg);
+ break;
+ case 'o':
+ fdout = open(optarg, O_WRONLY | O_CREAT, 0644);
+ if (fdout < 0)
+ errexit(optarg);
+ break;
+ default:
+ usage(argv[0]);
+ }
+ }
+
+ /* required paremeters */
+ if (!input_file || !h.modelid || !h.swVersionInt[0])
+ usage(argv[0]);
+
+ /* length fields */
+ h.len_t = htonl(sizeof(h) + file_len);
+ h.len_p = htonl(file_len);
+
+ /* crc fields */
+ init_crc32();
+ crc = crc32buf(input_file, file_len);
+ h.crc32_p = htonl(~crc);
+ crc = crc32buf((unsigned char *)&h, sizeof(h));
+ h.crc32_h = htonl(~crc);
+
+ /* dump new image */
+ write(fdout, &h, sizeof(h));
+ write(fdout, input_file, file_len);
+
+ /* close files */
+ munmap(input_file, file_len);
+ if (fdout != STDOUT_FILENO)
+ close(fdout);
+
+ return EXIT_SUCCESS;
+}
projects / openwrt / openwrt.git / commitdiff