ossl_do_PVK_header
if (!ossl_do_PVK_header(&p, 24, 0, isdss, &saltlen, &keylen))
if (!ossl_do_PVK_header(&p, sizeof(peekbuf), 0, &isdss, &saltlen, &keylen))
int ossl_do_PVK_header(const unsigned char **in, unsigned int length,
ok = ossl_do_PVK_header(&p, 24, 0, &isdss, &saltlen, &keylen) > 0;
return ossl_do_PVK_header(&in, data_len, 0, &isdss, &saltlen, &keylen);