dusk_cdf/element/
scalar.rs

1use std::io;
2use std::ops::{Deref, DerefMut};
3
4use crate::{
5    Config, DecodableElement, DecoderContext, Element, EncodableElement, EncoderContext, Preamble,
6};
7
8/// Scalar field representation with up to 256 bits.
9///
10/// This is agnostic to the curve choice and no canonical encoding assumption is involved.
11#[derive(Debug, Default, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
12pub struct Scalar {
13    scalar: [u8; Self::LEN],
14}
15
16impl Scalar {
17    /// Fixed serialized length
18    pub const LEN: usize = 32;
19}
20
21impl From<[u8; Scalar::LEN]> for Scalar {
22    fn from(scalar: [u8; Self::LEN]) -> Self {
23        Self { scalar }
24    }
25}
26
27impl AsRef<[u8]> for Scalar {
28    fn as_ref(&self) -> &[u8] {
29        &self.scalar
30    }
31}
32
33impl Deref for Scalar {
34    type Target = [u8; Self::LEN];
35
36    fn deref(&self) -> &Self::Target {
37        &self.scalar
38    }
39}
40
41impl DerefMut for Scalar {
42    fn deref_mut(&mut self) -> &mut Self::Target {
43        &mut self.scalar
44    }
45}
46
47impl Element for Scalar {
48    fn len(ctx: &Config) -> usize {
49        if ctx.zeroed_scalar_values {
50            0
51        } else {
52            Self::LEN
53        }
54    }
55
56    fn validate(&self, _preamble: &Preamble) -> io::Result<()> {
57        Ok(())
58    }
59}
60
61impl EncodableElement for Scalar {
62    fn to_buffer(&self, ctx: &mut EncoderContext, buf: &mut [u8]) {
63        if !ctx.config().zeroed_scalar_values {
64            let buf = &mut buf[..Self::LEN];
65
66            buf.copy_from_slice(&self.scalar);
67        }
68    }
69}
70
71impl DecodableElement for Scalar {
72    fn try_from_buffer_in_place<'b>(
73        &mut self,
74        ctx: &DecoderContext,
75        buf: &'b [u8],
76    ) -> io::Result<()> {
77        Self::validate_buffer(ctx.config(), buf)?;
78
79        if !ctx.config().zeroed_scalar_values {
80            self.scalar.copy_from_slice(&buf[..Self::LEN]);
81        }
82
83        Ok(())
84    }
85}
dusk_cdf/element/scalar.rs

dusk_cdf/element/
scalar.rs
