qudag_crypto/
hash.rs

1//! Cryptographic hash functions implementation.
2
3use thiserror::Error;
4
5/// Errors that can occur during hash operations.
6#[derive(Debug, Error)]
7pub enum HashError {
8    /// Input data is too large
9    #[error("Input data is too large")]
10    InputTooLarge,
11
12    /// Hash computation failed
13    #[error("Hash computation failed")]
14    ComputationFailed,
15}
16
17/// Hash function output.
18///
19/// # Examples
20///
21/// ```rust
22/// use qudag_crypto::hash::Digest;
23///
24/// let digest = Digest(vec![0x12, 0x34, 0x56, 0x78]);
25/// let bytes = digest.as_bytes();
26/// assert_eq!(bytes, &[0x12, 0x34, 0x56, 0x78]);
27/// ```
28#[derive(Debug, Clone, PartialEq, Eq)]
29pub struct Digest(Vec<u8>);
30
31impl Digest {
32    /// Get the digest as a byte slice.
33    ///
34    /// # Examples
35    ///
36    /// ```rust
37    /// use qudag_crypto::hash::Digest;
38    ///
39    /// let digest = Digest(vec![0x12, 0x34, 0x56, 0x78]);
40    /// let bytes = digest.as_bytes();
41    /// assert_eq!(bytes, &[0x12, 0x34, 0x56, 0x78]);
42    /// ```
43    pub fn as_bytes(&self) -> &[u8] {
44        &self.0
45    }
46
47    /// Convert the digest into a vector of bytes.
48    ///
49    /// # Examples
50    ///
51    /// ```rust
52    /// use qudag_crypto::hash::Digest;
53    ///
54    /// let digest = Digest(vec![0x12, 0x34, 0x56, 0x78]);
55    /// let bytes = digest.into_bytes();
56    /// assert_eq!(bytes, vec![0x12, 0x34, 0x56, 0x78]);
57    /// ```
58    pub fn into_bytes(self) -> Vec<u8> {
59        self.0
60    }
61}
62
63/// Cryptographic hash function trait.
64///
65/// # Examples
66///
67/// ```rust
68/// use qudag_crypto::hash::{HashFunction, HashError};
69///
70/// // Implement a simple hash function for demonstration
71/// struct SimpleHash {
72///     state: Vec<u8>,
73/// }
74///
75/// impl HashFunction for SimpleHash {
76///     fn new() -> Self {
77///         Self { state: Vec::new() }
78///     }
79///     
80///     fn update(&mut self, data: &[u8]) -> Result<(), HashError> {
81///         self.state.extend_from_slice(data);
82///         Ok(())
83///     }
84///     
85///     fn finalize(self) -> Result<qudag_crypto::hash::Digest, HashError> {
86///         // Simple checksum for example
87///         let sum = self.state.iter().fold(0u8, |acc, &x| acc.wrapping_add(x));
88///         Ok(qudag_crypto::hash::Digest(vec![sum]))
89///     }
90///     
91///     fn hash(data: &[u8]) -> Result<qudag_crypto::hash::Digest, HashError> {
92///         let mut hasher = Self::new();
93///         hasher.update(data)?;
94///         hasher.finalize()
95///     }
96/// }
97///
98/// // Use the hash function
99/// let data = b"hello world";
100/// let digest = SimpleHash::hash(data).unwrap();
101/// ```
102pub trait HashFunction {
103    /// Create a new hash instance.
104    ///
105    /// # Examples
106    ///
107    /// ```rust,ignore
108    /// let mut hasher = Blake3Hash::new();
109    /// ```
110    fn new() -> Self;
111
112    /// Update the hash state with input data.
113    ///
114    /// # Examples
115    ///
116    /// ```rust,ignore
117    /// let mut hasher = Blake3Hash::new();
118    /// hasher.update(b"hello").unwrap();
119    /// hasher.update(b" world").unwrap();
120    /// ```
121    fn update(&mut self, data: &[u8]) -> Result<(), HashError>;
122
123    /// Finalize the hash computation and return the digest.
124    ///
125    /// # Examples
126    ///
127    /// ```rust,ignore
128    /// let mut hasher = Blake3Hash::new();
129    /// hasher.update(b"hello world").unwrap();
130    /// let digest = hasher.finalize().unwrap();
131    /// ```
132    fn finalize(self) -> Result<Digest, HashError>;
133
134    /// Compute hash of input data in one step.
135    ///
136    /// # Examples
137    ///
138    /// ```rust,ignore
139    /// let digest = Blake3Hash::hash(b"hello world").unwrap();
140    /// ```
141    fn hash(data: &[u8]) -> Result<Digest, HashError>;
142}
qudag_crypto/hash.rs

qudag_crypto/
hash.rs
