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/* J J Larworthy 27 September 2006 */
/* file to read the boot sector of a dis and the loaded image and report
* if the boot rom would accept the data as intact and suitable for use
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
extern uint32_t crc32(uint32_t, const unsigned char *, unsigned int);
#define NUMBER_VECTORS 12
struct {
unsigned int start_vector[NUMBER_VECTORS];
char code[4];
unsigned int header_length;
unsigned int reserved[3];
unsigned int length;
unsigned int img_CRC;
unsigned int CRC;
} img_header;
void print_usage(void)
{
printf("update_header file.bin\n");
}
void print_header(void)
{
int i;
printf("vectors in header\n");
for (i = 0; i < NUMBER_VECTORS; i++) {
printf("%d:0x%08x\n", i, img_header.start_vector[i]);
}
printf("length:%8x\nimg_CRC:0x%08x\nHeader CRC:0x%08x\n",
img_header.length, img_header.img_CRC, img_header.CRC);
}
int main(int argc, char **argv)
{
int in_file;
int status;
int unsigned crc;
int file_length;
int len;
struct stat file_stat;
void *executable;
in_file = open(argv[1], O_RDWR);
if (in_file < 0) {
printf("failed to open file:%s\n", argv[optind]);
return -ENOENT;
}
status = fstat(in_file, &file_stat);
/* read header and obtain size of image */
status = read(in_file, &img_header, sizeof(img_header));
file_length = file_stat.st_size - sizeof(img_header);
if (img_header.length != file_length) {
printf("size in header:%d, size of file: %d\n",
img_header.length, file_length);
}
img_header.length = file_length;
/* read working image and CRC */
executable = malloc(file_length);
status = read(in_file, executable, file_length);
if (status != file_length) {
printf("Failed to load image\n");
return -ENOENT;
}
/* verify image CRC */
crc = crc32(0, (const unsigned char *) executable, img_header.length);
if (crc != img_header.img_CRC) {
printf("New Image CRC:0x%08x, hdr:0x%08x\n", crc,
img_header.img_CRC);
img_header.img_CRC = crc;
}
memcpy(img_header.code, "BOOT", 4);
img_header.header_length = sizeof(img_header);
/* check header CRC */
crc = crc32(0, (const unsigned char *) &img_header,
sizeof(img_header) - sizeof(unsigned int));
if (crc != img_header.CRC) {
printf("New header CRC - crc:0x%08x hdr:0x%08x\n", crc,
img_header.CRC);
img_header.CRC = crc;
}
/* re-write the file */
status = lseek(in_file, 0, SEEK_SET);
if (status != 0) {
printf("failed to rewind\n");
return 1;
}
len = write(in_file, &img_header, sizeof(img_header));
assert(len == sizeof(img_header));
len = write(in_file, executable, file_length);
assert(len == file_length);
close(in_file);
return 0;
}
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