Move memo to its own module under note_encryption, turn try_from into a match cmp

This commit is contained in:
Deirdre Connolly 2020-02-12 20:21:59 -05:00 committed by Deirdre Connolly
parent 54b1172dc8
commit 01fcce53f4
2 changed files with 84 additions and 88 deletions

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@ -1,92 +1,5 @@
//! Note encryption types.
use std::{
convert::{AsRef, From},
fmt,
};
pub mod memo;
mod sapling;
mod sprout;
/// A 512-byte _Memo_ field associated with a note, as described in
/// [protocol specification §5.5][ps].
///
/// The _Memo- field of a note is a plaintext type; the parent note is
/// what is encrypted and stored on the blockchain. The underlying
/// usage of the memo field is by agreement between the sender and
/// recipient of the note.
///
/// [ps]: https://zips.z.cash/protocol/protocol.pdf#notept
#[derive(Clone, Copy)]
pub struct Memo([u8; 512]);
impl<T: AsRef<[u8]>> From<T> for Memo {
fn from(input: T) -> Self {
let input_bytes: &[u8] = input.as_ref();
let mut full_bytes = [0; 512];
if input_bytes.len() < 512 {
full_bytes[0..input_bytes.len()].copy_from_slice(input_bytes);
Memo(full_bytes)
} else if input_bytes.len() == 512 {
full_bytes[..].copy_from_slice(input_bytes);
Memo(full_bytes)
} else {
// Because this is a From impl, we truncate your input
// rather than return any Memo at all.
full_bytes.copy_from_slice(&input_bytes[0..512]);
Memo(full_bytes)
}
}
}
impl fmt::Debug for Memo {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let output: String;
// This saves work but if the 'valid utf8 string' is just a
// bunch of numbers, it prints them out like
// 'Memo("\u{0}\u{0}..")', so. ¯\_(ツ)_/¯
match std::str::from_utf8(&self.0[..]) {
Ok(memo) => output = String::from(memo),
_ => output = hex::encode(&self.0[..]),
}
f.debug_tuple("Memo").field(&output).finish()
}
}
#[test]
fn memo_fmt() {
let memo = Memo(
*b"thiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiis \
iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiis \
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa \
veeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeryyyyyyyyyyyyyyyyyyyyyyyyyy \
looooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooong \
meeeeeeeeeeeeeeeeeeemooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo \
but it's just short enough",
);
assert_eq!(format!("{:?}", memo),
"Memo(\"thiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiis iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiis aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa veeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeryyyyyyyyyyyyyyyyyyyyyyyyyy looooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooong meeeeeeeeeeeeeeeeeeemooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo but it\\\'s just short enough\")"
);
let mut some_bytes = [0u8; 512];
some_bytes[0] = 0xF6;
assert_eq!(format!("{:?}", Memo(some_bytes)),
"Memo(\"f600000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000\")"
);
}
#[test]
fn memo_from_string() {
let memo = Memo::from("foo bar baz");
let mut bytes = [0; 512];
bytes[0..11].copy_from_slice(&[102, 111, 111, 32, 98, 97, 114, 32, 98, 97, 122]);
assert!(memo.0.iter().eq(bytes.iter()));
}

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@ -0,0 +1,83 @@
use std::{cmp, convert::TryFrom, fmt};
/// A 512-byte _Memo_ field associated with a note, as described in
/// [protocol specification §5.5][ps].
///
/// The _Memo_ field of a note is a plaintext type; the parent note is
/// what is encrypted and stored on the blockchain. The underlying
/// usage of the memo field is by agreement between the sender and
/// recipient of the note.
///
/// [ps]: https://zips.z.cash/protocol/protocol.pdf#notept
#[derive(Clone, Copy)]
pub struct Memo([u8; 512]);
impl<'a> TryFrom<&'a [u8]> for Memo {
type Error = &'static str;
fn try_from(input: &'a [u8]) -> Result<Self, Self::Error> {
let mut full_bytes = [0; 512];
match input.len().cmp(&512) {
cmp::Ordering::Less => {
full_bytes[0..input.len()].copy_from_slice(input);
Ok(Memo(full_bytes))
}
cmp::Ordering::Equal => {
full_bytes[..].copy_from_slice(input);
Ok(Memo(full_bytes))
}
cmp::Ordering::Greater => Err("Memos have a max length of 512 bytes."),
}
}
}
impl fmt::Debug for Memo {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let output: String;
// This saves work but if the 'valid utf8 string' is just a
// bunch of numbers, it prints them out like
// 'Memo("\u{0}\u{0}..")', so. ¯\_(ツ)_/¯
match std::str::from_utf8(&self.0[..]) {
Ok(memo) => output = String::from(memo),
_ => output = hex::encode(&self.0[..]),
}
f.debug_tuple("Memo").field(&output).finish()
}
}
#[test]
fn memo_fmt() {
let memo = Memo(
*b"thiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiis \
iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiis \
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa \
veeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeryyyyyyyyyyyyyyyyyyyyyyyyyy \
looooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooong \
meeeeeeeeeeeeeeeeeeemooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo \
but it's just short enough",
);
assert_eq!(format!("{:?}", memo),
"Memo(\"thiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiis iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiis aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa veeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeryyyyyyyyyyyyyyyyyyyyyyyyyy looooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooong meeeeeeeeeeeeeeeeeeemooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo but it\\\'s just short enough\")"
);
let mut some_bytes = [0u8; 512];
some_bytes[0] = 0xF6;
assert_eq!(format!("{:?}", Memo(some_bytes)),
"Memo(\"f600000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000\")"
);
}
#[test]
fn memo_from_string() {
let memo = Memo::try_from("foo bar baz".as_ref()).unwrap();
let mut bytes = [0; 512];
bytes[0..11].copy_from_slice(&[102, 111, 111, 32, 98, 97, 114, 32, 98, 97, 122]);
assert!(memo.0.iter().eq(bytes.iter()));
}