static int decode_header_info(struct header *hdr, RSA *pkey, int *img_len)
{
struct little_header lhdr;
/* Decode header information */
if (fb_seek_end(sizeof(lhdr)) != 0) {
error("image not cryptographically enabled");
exit(NO_CRYPT);
}
fb_read(&lhdr, sizeof(lhdr));
if (lhdr.magic != htons(LITTLE_CRYPTO_MAGIC)) {
#ifdef CONFIG_USER_NETFLASH_CRYPTO_OPTIONAL
notice("WARNING: no crypto header found\n");
return 0;
#else
error("size magic incorrect");
exit(BAD_CRYPT_MAGIC);
#endif
}
{
unsigned short hlen = ntohs(lhdr.hlen);
unsigned char tmp[hlen];
unsigned char t2[hlen];
int len;
if (fb_seek_end(sizeof(lhdr) + hlen) != 0) {
error("crypt header length invalid");
exit(BAD_CRYPT_LEN);
}
fb_read(tmp, hlen);
#ifdef CONFIG_USER_NETFLASH_CRYPTO_V2
fb_meta_add(sizeof(lhdr) + hlen);
*img_len = fb_len() - fb_meta_len();
#else
fb_trim(sizeof(lhdr) + hlen);
*img_len = fb_len();
#endif
len = RSA_public_decrypt(hlen, tmp, t2,
pkey, RSA_PKCS1_PADDING);
if (len == -1) {
error("decrypt failed");
exit(BAD_DECRYPT);
}
if (len != sizeof(struct header)) {
error("length mismatch %d %d\n", (int)sizeof(struct header), len);
}
memcpy(hdr, t2, sizeof(struct header));
}
if (hdr->magic != htonl(CRYPTO_MAGIC)) {
error("image not cryptographically enabled");
exit(NO_CRYPT);
}
return 1;
}
/*
* The last few bytes of the image look like the following:
*
* \0version\0vendore_name\0product_namechksum
* the chksum is 16bits wide, and the version is no more than 20bytes.
*
* version is w.x.y[nz], where n is ubpi, and w, x, y and z are 1 or 2 digit
* numbers.
*
* vendorName and productName may be a comma separated list of names
* which are acceptable
*/
int check_vendor(void)
{
int versionInfo;
/*
* Point to what should be the last byte in the product name string.
*/
if (fb_seek_end(1) != 0)
return 5;
/*
* Now try to get the vendor/product/version strings, from the end
* of the image
*/
if (get_string(imageProductName, MAX_PRODUCT_SIZE) != 0)
return 5;
if (get_string(imageVendorName, MAX_VENDOR_SIZE) != 0)
return 5;
if (get_string(imageVersion, MAX_VERSION_SIZE) != 0)
return 5;
/* Looks like there was versioning information there, strip it off
* now so that we don't write it to flash, or try to decompress it, etc */
fb_trim(strlen(imageProductName) + strlen(imageVendorName) + strlen(imageVersion) + 3);
/*
* Check the product name. Our product name may be a comma separated list of names.
*/
if (!check_match(imageProductName, our_product_name)) {
return 1;
}
/*
* Check the vendor name. Our vendor name may be a comma separated list of names.
*/
if (!check_match(imageVendorName, our_vendor_name)) {
return 2;
}
/*
* Check the version number.
*/
versionInfo = check_version_info(our_image_version, imageVersion);
return versionInfo;
}