OpenWrt – Rev 1
?pathlinks?
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/types.h>
#include <unistd.h>
#include <byteswap.h>
#include <endian.h>
#include <getopt.h>
#if !defined(__BYTE_ORDER)
#error "Unknown byte order"
#endif
#if __BYTE_ORDER == __BIG_ENDIAN
#define cpu_to_be32(x) (x)
#elif __BYTE_ORDER == __LITTLE_ENDIAN
#define cpu_to_be32(x) bswap_32(x)
#else
#error "Unsupported endianness"
#endif
/* #define DEBUG 1 */
#ifdef DEBUG
#define DBG(...) {printf(__VA_ARGS__); }
#else
#define DBG(...) {}
#endif
#define ERR(...) {printf(__VA_ARGS__); }
/*
* Fw Header Layout for Netgear / Sercomm devices (bytes)
*
* Size : 512 bytes + zipped image size
*
* Locations:
* magic : 0-6 ASCII
* version: 7-11 fixed
* hwID : 11-44 ASCII
* hwVer : 45-54 ASCII
* swVer : 55-62 uint32_t in BE
* magic : 63-69 ASCII
* ChkSum : 511 Inverse value of the full image checksum while this location is 0x00
*/
static const char* magic = "sErCoMm"; /* 7 */
static const unsigned char version[4] = { 0x00, 0x01, 0x00, 0x00 };
static const int header_sz = 512;
static const int footer_sz = 71;
static int is_header = 1;
struct file_info {
char* file_name; /* name of the file */
char* file_data; /* data of the file in memory */
u_int32_t file_size; /* length of the file */
};
static u_int8_t getCheckSum(char* data, int len) {
u_int8_t new = 0;
int i;
if (!data) {
ERR("Invalid pointer provided!\n");
return 0;
}
for (i = 0; i < len; i++) {
new += data[i];
}
return new;
}
/*
* read file into buffer
* add space for header/footer
*/
static int copyToOutputBuf(struct file_info* finfo) {
FILE* fp = NULL;
int file_sz = 0;
int extra_sz;
int hdr_pos;
int img_pos;
if (!finfo || !finfo->file_name) {
ERR("Invalid pointer provided!\n");
return -1;
}
DBG("Opening file: %s\n", finfo->file_name);
if (!(fp = fopen(finfo->file_name, "rb"))) {
ERR("Error opening file: %s\n", finfo->file_name);
return -1;
}
/* Get filesize */
rewind(fp);
fseek(fp, 0L, SEEK_END);
file_sz = ftell(fp);
rewind(fp);
if (file_sz < 1) {
ERR("Error getting filesize: %s\n", finfo->file_name);
fclose(fp);
return -1;
}
if (is_header) {
extra_sz = header_sz;
hdr_pos = 0;
img_pos = header_sz;
} else {
extra_sz = footer_sz;
hdr_pos = file_sz;
img_pos = 0;
}
DBG("Filesize: %i\n", file_sz);
finfo->file_size = file_sz + extra_sz;
if (!(finfo->file_data = malloc(finfo->file_size))) {
ERR("Out of memory!\n");
fclose(fp);
return -1;
}
/* init header/footer bytes */
memset(finfo->file_data + hdr_pos, 0, extra_sz);
/* read file and take care of leading header if exists */
if (fread(finfo->file_data + img_pos, 1, file_sz, fp) != file_sz) {
ERR("Error reading file %s\n", finfo->file_name);
fclose(fp);
return -1;
}
DBG("File: read successful\n");
fclose(fp);
return hdr_pos;
}
static int writeFile(struct file_info* finfo) {
FILE* fp;
if (!finfo || !finfo->file_name) {
ERR("Invalid pointer provided!\n");
return -1;
}
DBG("Opening file: %s\n", finfo->file_name);
if (!(fp = fopen(finfo->file_name, "w"))) {
ERR("Error opening file: %s\n", finfo->file_name);
return -1;
}
DBG("Writing file: %s\n", finfo->file_name);
if (fwrite(finfo->file_data, 1, finfo->file_size, fp) != finfo->file_size) {
ERR("Wanted to write, but something went wrong!\n");
fclose(fp);
return -1;
}
fclose(fp);
return 0;
}
static void usage(char* argv[]) {
printf("Usage: %s [OPTIONS...]\n"
"\n"
"Options:\n"
" -f add sercom footer (if absent, header)\n"
" -b <hwid> use hardware id specified with <hwid> (ASCII)\n"
" -r <hwrev> use hardware revision specified with <hwrev> (ASCII)\n"
" -v <version> set image version to <version> (decimal, hex or octal notation)\n"
" -i <file> input file\n"
, argv[0]);
}
int main(int argc, char* argv[]) {
struct file_info image = { 0 };
char* hwID = NULL;
char* hwVer = NULL;
u_int32_t swVer = 0;
u_int8_t chkSum;
int hdr_offset;
while ( 1 ) {
int c;
c = getopt(argc, argv, "b:i:r:v:f");
if (c == -1)
break;
switch (c) {
case 'b':
hwID = optarg;
break;
case 'f':
is_header = 0;
break;
case 'i':
image.file_name = optarg;
break;
case 'r':
hwVer = optarg;
break;
case 'v':
swVer = (u_int32_t) strtol(optarg, NULL, 0);
swVer = cpu_to_be32(swVer);
break;
default:
usage(argv);
return EXIT_FAILURE;
}
}
if (!hwID || !hwVer || !image.file_name) {
usage(argv);
return EXIT_FAILURE;
}
/*
* copy input to buffer, add extra space for header/footer and return
* header position
*/
hdr_offset = copyToOutputBuf(&image);
if (hdr_offset < 0)
return EXIT_FAILURE;
DBG("Filling header: %s %s %2X %s\n", hwID, hwVer, swVer, magic);
strncpy(image.file_data + hdr_offset + 0, magic, 7);
memcpy(image.file_data + hdr_offset + 7, version, sizeof(version));
strncpy(image.file_data + hdr_offset + 11, hwID, 34);
strncpy(image.file_data + hdr_offset + 45, hwVer, 10);
memcpy(image.file_data + hdr_offset + 55, &swVer, sizeof(swVer));
strncpy(image.file_data + hdr_offset + 63, magic, 7);
/* calculate checksum and invert checksum */
if (is_header) {
chkSum = getCheckSum(image.file_data, image.file_size);
chkSum = (chkSum ^ 0xFF) + 1;
DBG("Checksum for Image: %hhX\n", chkSum);
/* write checksum to header */
image.file_data[511] = (char) chkSum;
}
/* overwrite input file */
if (writeFile(&image))
return EXIT_FAILURE;
return EXIT_SUCCESS;
}