proxmox-protocol/src/tools.rs

   1 use failure::{bail, Error};
   2
   3 pub fn digest_to_hex(digest: &[u8]) -> String {
   4     const HEX_CHARS: &'static [u8; 16] = b"0123456789abcdef";
   5
   6     let mut buf = Vec::<u8>::with_capacity(digest.len() * 2);
   7
   8     for i in 0..digest.len() {
   9         buf.push(HEX_CHARS[(digest[i] >> 4) as usize]);
  10         buf.push(HEX_CHARS[(digest[i] & 0xf) as usize]);
  11     }
  12
  13     unsafe { String::from_utf8_unchecked(buf) }
  14 }
  15
  16 pub unsafe fn swapped_data_to_buf<T>(data: &T) -> &[u8] {
  17     std::slice::from_raw_parts(data as *const T as *const u8, std::mem::size_of::<T>())
  18 }
  19
  20 fn hex_nibble(c: u8) -> Result<u8, Error> {
  21     Ok(match c {
  22         b'0'..=b'9' => c - b'0',
  23         b'a'..=b'f' => c - b'a' + 0xa,
  24         b'A'..=b'F' => c - b'A' + 0xa,
  25         _ => bail!("not a hex digit: {}", c as char),
  26     })
  27 }
  28
  29 #[inline]
  30 pub fn parse_hex_digest<T: AsRef<[u8]>>(hex: T) -> Result<[u8; 32], Error> {
  31     let mut digest: [u8; 32] = unsafe { std::mem::uninitialized() };
  32
  33     let hex = hex.as_ref();
  34
  35     if hex.len() != 64 {
  36         bail!(
  37             "invalid hex digest ({} instead of 64 digits long)",
  38             hex.len()
  39         );
  40     }
  41
  42     for i in 0..32 {
  43         digest[i] = (hex_nibble(hex[i * 2])? << 4) + hex_nibble(hex[i * 2 + 1])?;
  44     }
  45
  46     Ok(digest)
  47 }