src/tools.rs: implement hex_to_digest

This commit is contained in:
Dietmar Maurer 2019-05-19 12:15:46 +02:00
parent 751030aa7c
commit f2269d8f99

View File

@ -564,10 +564,9 @@ pub fn get_hardware_address() -> Result<String, Error> {
Ok(format!("{:0x}", digest))
}
const HEX_CHARS: &'static [u8; 16] = b"0123456789abcdef";
pub fn digest_to_hex(digest: &[u8]) -> String {
const HEX_CHARS: &'static [u8; 16] = b"0123456789abcdef";
let mut buf = Vec::<u8>::with_capacity(digest.len()*2);
for i in 0..digest.len() {
@ -578,6 +577,29 @@ pub fn digest_to_hex(digest: &[u8]) -> String {
unsafe { String::from_utf8_unchecked(buf) }
}
pub fn hex_to_digest(hex: &str) -> Result<[u8; 32], Error> {
let mut digest = [0u8; 32];
let bytes = hex.as_bytes();
if bytes.len() != 64 { bail!("got wrong digest length."); }
let mut pos = 0;
for pair in bytes.chunks(2) {
if pos >= digest.len() { bail!("hex digest too long."); }
let mut h = pair[0];
if h >= b'0' && h <= b'f' { h = h - b'0'; } else { bail!("found illegal hex character."); }
let mut l = pair[1];
if l >= b'0' && l <= b'f' { l = l - b'0'; } else { bail!("found illegal hex character."); }
digest[pos] = (h<<4)|l;
pos +=1;
}
if pos != digest.len() { bail!("hex digest too short."); }
Ok(digest)
}
pub fn assert_if_modified(digest1: &str, digest2: &str) -> Result<(), Error> {
if digest1 != digest2 {
bail!("detected modified configuration - file changed by other user? Try again.");