sha1/
lib.rs

1//! Pure Rust implementation of the [SHA-1][1] cryptographic hash algorithm
2//! with optional hardware-specific optimizations.
3//!
4//! # 🚨 Warning: Cryptographically Broken! 🚨
5//!
6//! The SHA-1 hash function should be considered cryptographically broken and
7//! unsuitable for further use in any security critical capacity, as it is
8//! [practically vulnerable to chosen-prefix collisions][2].
9//!
10//! We provide this crate for legacy interoperability purposes only.
11//!
12//! # Usage
13//!
14//! ```rust
15//! use hex_literal::hex;
16//! use sha1::{Sha1, Digest};
17//!
18//! // create a Sha1 object
19//! let mut hasher = Sha1::new();
20//!
21//! // process input message
22//! hasher.update(b"hello world");
23//!
24//! // acquire hash digest in the form of GenericArray,
25//! // which in this case is equivalent to [u8; 20]
26//! let result = hasher.finalize();
27//! assert_eq!(result[..], hex!("2aae6c35c94fcfb415dbe95f408b9ce91ee846ed"));
28//! ```
29//!
30//! Also see [RustCrypto/hashes][3] readme.
31//!
32//! # Note for users of `sha1 v0.6`
33//!
34//! This crate has been transferred to the RustCrypto organization and uses
35//! implementation previously published as the `sha-1` crate. The previous
36//! zero dependencies version is now published as the [`sha1_smol`] crate.
37//!
38//! [1]: https://en.wikipedia.org/wiki/SHA-1
39//! [2]: https://sha-mbles.github.io/
40//! [3]: https://github.com/RustCrypto/hashes
41//! [`sha1_smol`]: https://github.com/mitsuhiko/sha1-smol/
42
43#![no_std]
44#![cfg_attr(docsrs, feature(doc_cfg))]
45#![doc(
46    html_logo_url = "https://raw.githubusercontent.com/RustCrypto/media/6ee8e381/logo.svg",
47    html_favicon_url = "https://raw.githubusercontent.com/RustCrypto/media/6ee8e381/logo.svg"
48)]
49#![warn(missing_docs, rust_2018_idioms)]
50
51pub use digest::{self, Digest};
52
53use core::{fmt, slice::from_ref};
54#[cfg(feature = "oid")]
55use digest::const_oid::{AssociatedOid, ObjectIdentifier};
56use digest::{
57    block_buffer::Eager,
58    core_api::{
59        AlgorithmName, Block, BlockSizeUser, Buffer, BufferKindUser, CoreWrapper, FixedOutputCore,
60        OutputSizeUser, Reset, UpdateCore,
61    },
62    typenum::{Unsigned, U20, U64},
63    HashMarker, Output,
64};
65
66mod compress;
67
68#[cfg(feature = "compress")]
69pub use compress::compress;
70#[cfg(not(feature = "compress"))]
71use compress::compress;
72
73const STATE_LEN: usize = 5;
74
75/// Core SHA-1 hasher state.
76#[derive(Clone)]
77pub struct Sha1Core {
78    h: [u32; STATE_LEN],
79    block_len: u64,
80}
81
82impl HashMarker for Sha1Core {}
83
84impl BlockSizeUser for Sha1Core {
85    type BlockSize = U64;
86}
87
88impl BufferKindUser for Sha1Core {
89    type BufferKind = Eager;
90}
91
92impl OutputSizeUser for Sha1Core {
93    type OutputSize = U20;
94}
95
96impl UpdateCore for Sha1Core {
97    #[inline]
98    fn update_blocks(&mut self, blocks: &[Block<Self>]) {
99        self.block_len += blocks.len() as u64;
100        compress(&mut self.h, blocks);
101    }
102}
103
104impl FixedOutputCore for Sha1Core {
105    #[inline]
106    fn finalize_fixed_core(&mut self, buffer: &mut Buffer<Self>, out: &mut Output<Self>) {
107        let bs = Self::BlockSize::U64;
108        let bit_len = 8 * (buffer.get_pos() as u64 + bs * self.block_len);
109
110        let mut h = self.h;
111        buffer.len64_padding_be(bit_len, |b| compress(&mut h, from_ref(b)));
112        for (chunk, v) in out.chunks_exact_mut(4).zip(h.iter()) {
113            chunk.copy_from_slice(&v.to_be_bytes());
114        }
115    }
116}
117
118impl Default for Sha1Core {
119    #[inline]
120    fn default() -> Self {
121        Self {
122            h: [0x67452301, 0xEFCDAB89, 0x98BADCFE, 0x10325476, 0xC3D2E1F0],
123            block_len: 0,
124        }
125    }
126}
127
128impl Reset for Sha1Core {
129    #[inline]
130    fn reset(&mut self) {
131        *self = Default::default();
132    }
133}
134
135impl AlgorithmName for Sha1Core {
136    fn write_alg_name(f: &mut fmt::Formatter<'_>) -> fmt::Result {
137        f.write_str("Sha1")
138    }
139}
140
141impl fmt::Debug for Sha1Core {
142    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
143        f.write_str("Sha1Core { ... }")
144    }
145}
146
147#[cfg(feature = "oid")]
148#[cfg_attr(docsrs, doc(cfg(feature = "oid")))]
149impl AssociatedOid for Sha1Core {
150    const OID: ObjectIdentifier = ObjectIdentifier::new_unwrap("1.3.14.3.2.26");
151}
152
153/// SHA-1 hasher state.
154pub type Sha1 = CoreWrapper<Sha1Core>;
sha1/lib.rs

sha1/
lib.rs
