use core::{borrow, fmt, ops, str};
#[cfg(feature = "serde")]
use serde::{Deserialize, Deserializer, Serialize, Serializer};
use crate::{FromSliceError, Hash, HashEngine};
#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
#[cfg_attr(feature = "schemars", schemars(transparent))]
#[repr(transparent)]
pub struct Hmac<T: Hash>(T);
impl<T: Hash + str::FromStr> str::FromStr for Hmac<T> {
type Err = <T as str::FromStr>::Err;
fn from_str(s: &str) -> Result<Self, Self::Err> { Ok(Hmac(str::FromStr::from_str(s)?)) }
}
pub struct HmacMidState<T: Hash> {
pub inner: <T::Engine as HashEngine>::MidState,
pub outer: <T::Engine as HashEngine>::MidState,
}
#[derive(Clone)]
pub struct HmacEngine<T: Hash> {
iengine: T::Engine,
oengine: T::Engine,
}
impl<T: Hash> Default for HmacEngine<T> {
fn default() -> Self { HmacEngine::new(&[]) }
}
impl<T: Hash> HmacEngine<T> {
pub fn new(key: &[u8]) -> HmacEngine<T> {
debug_assert!(T::Engine::BLOCK_SIZE <= 128);
let mut ipad = [0x36u8; 128];
let mut opad = [0x5cu8; 128];
let mut ret = HmacEngine { iengine: <T as Hash>::engine(), oengine: <T as Hash>::engine() };
if key.len() > T::Engine::BLOCK_SIZE {
let hash = <T as Hash>::hash(key);
for (b_i, b_h) in ipad.iter_mut().zip(&hash[..]) {
*b_i ^= *b_h;
}
for (b_o, b_h) in opad.iter_mut().zip(&hash[..]) {
*b_o ^= *b_h;
}
} else {
for (b_i, b_h) in ipad.iter_mut().zip(key) {
*b_i ^= *b_h;
}
for (b_o, b_h) in opad.iter_mut().zip(key) {
*b_o ^= *b_h;
}
};
HashEngine::input(&mut ret.iengine, &ipad[..T::Engine::BLOCK_SIZE]);
HashEngine::input(&mut ret.oengine, &opad[..T::Engine::BLOCK_SIZE]);
ret
}
pub fn from_inner_engines(iengine: T::Engine, oengine: T::Engine) -> HmacEngine<T> {
HmacEngine { iengine, oengine }
}
}
impl<T: Hash> HashEngine for HmacEngine<T> {
type MidState = HmacMidState<T>;
fn midstate(&self) -> Self::MidState {
HmacMidState { inner: self.iengine.midstate(), outer: self.oengine.midstate() }
}
const BLOCK_SIZE: usize = T::Engine::BLOCK_SIZE;
fn n_bytes_hashed(&self) -> usize { self.iengine.n_bytes_hashed() }
fn input(&mut self, buf: &[u8]) { self.iengine.input(buf) }
}
impl<T: Hash> fmt::Debug for Hmac<T> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { fmt::Debug::fmt(&self.0, f) }
}
impl<T: Hash> fmt::Display for Hmac<T> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { fmt::Display::fmt(&self.0, f) }
}
impl<T: Hash> fmt::LowerHex for Hmac<T> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { fmt::LowerHex::fmt(&self.0, f) }
}
impl<T: Hash> ops::Index<usize> for Hmac<T> {
type Output = u8;
fn index(&self, index: usize) -> &u8 { &self.0[index] }
}
impl<T: Hash> ops::Index<ops::Range<usize>> for Hmac<T> {
type Output = [u8];
fn index(&self, index: ops::Range<usize>) -> &[u8] { &self.0[index] }
}
impl<T: Hash> ops::Index<ops::RangeFrom<usize>> for Hmac<T> {
type Output = [u8];
fn index(&self, index: ops::RangeFrom<usize>) -> &[u8] { &self.0[index] }
}
impl<T: Hash> ops::Index<ops::RangeTo<usize>> for Hmac<T> {
type Output = [u8];
fn index(&self, index: ops::RangeTo<usize>) -> &[u8] { &self.0[index] }
}
impl<T: Hash> ops::Index<ops::RangeFull> for Hmac<T> {
type Output = [u8];
fn index(&self, index: ops::RangeFull) -> &[u8] { &self.0[index] }
}
impl<T: Hash> borrow::Borrow<[u8]> for Hmac<T> {
fn borrow(&self) -> &[u8] { &self[..] }
}
impl<T: Hash> Hash for Hmac<T> {
type Engine = HmacEngine<T>;
type Bytes = T::Bytes;
fn from_engine(mut e: HmacEngine<T>) -> Hmac<T> {
let ihash = T::from_engine(e.iengine);
e.oengine.input(&ihash[..]);
let ohash = T::from_engine(e.oengine);
Hmac(ohash)
}
const LEN: usize = T::LEN;
fn from_slice(sl: &[u8]) -> Result<Hmac<T>, FromSliceError> { T::from_slice(sl).map(Hmac) }
fn to_byte_array(self) -> Self::Bytes { self.0.to_byte_array() }
fn as_byte_array(&self) -> &Self::Bytes { self.0.as_byte_array() }
fn from_byte_array(bytes: T::Bytes) -> Self { Hmac(T::from_byte_array(bytes)) }
fn all_zeros() -> Self {
let zeros = T::all_zeros();
Hmac(zeros)
}
}
#[cfg(feature = "serde")]
impl<T: Hash + Serialize> Serialize for Hmac<T> {
fn serialize<S: Serializer>(&self, s: S) -> Result<S::Ok, S::Error> {
Serialize::serialize(&self.0, s)
}
}
#[cfg(feature = "serde")]
impl<'de, T: Hash + Deserialize<'de>> Deserialize<'de> for Hmac<T> {
fn deserialize<D: Deserializer<'de>>(d: D) -> Result<Hmac<T>, D::Error> {
let bytes = Deserialize::deserialize(d)?;
Ok(Hmac(bytes))
}
}
#[cfg(test)]
mod tests {
#[test]
#[cfg(feature = "alloc")]
fn test() {
use crate::{sha256, Hash, HashEngine, Hmac, HmacEngine};
#[derive(Clone)]
struct Test {
key: Vec<u8>,
input: Vec<u8>,
output: Vec<u8>,
}
#[rustfmt::skip]
let tests = vec![
Test {
key: vec![ 0x0b; 20],
input: vec![0x48, 0x69, 0x20, 0x54, 0x68, 0x65, 0x72, 0x65],
output: vec![
0xb0, 0x34, 0x4c, 0x61, 0xd8, 0xdb, 0x38, 0x53,
0x5c, 0xa8, 0xaf, 0xce, 0xaf, 0x0b, 0xf1, 0x2b,
0x88, 0x1d, 0xc2, 0x00, 0xc9, 0x83, 0x3d, 0xa7,
0x26, 0xe9, 0x37, 0x6c, 0x2e, 0x32, 0xcf, 0xf7,
],
},
Test {
key: vec![ 0x4a, 0x65, 0x66, 0x65 ],
input: vec![
0x77, 0x68, 0x61, 0x74, 0x20, 0x64, 0x6f, 0x20,
0x79, 0x61, 0x20, 0x77, 0x61, 0x6e, 0x74, 0x20,
0x66, 0x6f, 0x72, 0x20, 0x6e, 0x6f, 0x74, 0x68,
0x69, 0x6e, 0x67, 0x3f,
],
output: vec![
0x5b, 0xdc, 0xc1, 0x46, 0xbf, 0x60, 0x75, 0x4e,
0x6a, 0x04, 0x24, 0x26, 0x08, 0x95, 0x75, 0xc7,
0x5a, 0x00, 0x3f, 0x08, 0x9d, 0x27, 0x39, 0x83,
0x9d, 0xec, 0x58, 0xb9, 0x64, 0xec, 0x38, 0x43,
],
},
Test {
key: vec![ 0xaa; 20 ],
input: vec![ 0xdd; 50 ],
output: vec![
0x77, 0x3e, 0xa9, 0x1e, 0x36, 0x80, 0x0e, 0x46,
0x85, 0x4d, 0xb8, 0xeb, 0xd0, 0x91, 0x81, 0xa7,
0x29, 0x59, 0x09, 0x8b, 0x3e, 0xf8, 0xc1, 0x22,
0xd9, 0x63, 0x55, 0x14, 0xce, 0xd5, 0x65, 0xfe,
],
},
Test {
key: vec![
0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08,
0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10,
0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18,
0x19
],
input: vec![ 0xcd; 50 ],
output: vec![
0x82, 0x55, 0x8a, 0x38, 0x9a, 0x44, 0x3c, 0x0e,
0xa4, 0xcc, 0x81, 0x98, 0x99, 0xf2, 0x08, 0x3a,
0x85, 0xf0, 0xfa, 0xa3, 0xe5, 0x78, 0xf8, 0x07,
0x7a, 0x2e, 0x3f, 0xf4, 0x67, 0x29, 0x66, 0x5b,
],
},
Test {
key: vec! [ 0xaa; 131 ],
input: vec![
0x54, 0x65, 0x73, 0x74, 0x20, 0x55, 0x73, 0x69,
0x6e, 0x67, 0x20, 0x4c, 0x61, 0x72, 0x67, 0x65,
0x72, 0x20, 0x54, 0x68, 0x61, 0x6e, 0x20, 0x42,
0x6c, 0x6f, 0x63, 0x6b, 0x2d, 0x53, 0x69, 0x7a,
0x65, 0x20, 0x4b, 0x65, 0x79, 0x20, 0x2d, 0x20,
0x48, 0x61, 0x73, 0x68, 0x20, 0x4b, 0x65, 0x79,
0x20, 0x46, 0x69, 0x72, 0x73, 0x74,
],
output: vec![
0x60, 0xe4, 0x31, 0x59, 0x1e, 0xe0, 0xb6, 0x7f,
0x0d, 0x8a, 0x26, 0xaa, 0xcb, 0xf5, 0xb7, 0x7f,
0x8e, 0x0b, 0xc6, 0x21, 0x37, 0x28, 0xc5, 0x14,
0x05, 0x46, 0x04, 0x0f, 0x0e, 0xe3, 0x7f, 0x54,
],
},
Test {
key: vec! [ 0xaa; 131 ],
input: vec![
0x54, 0x68, 0x69, 0x73, 0x20, 0x69, 0x73, 0x20,
0x61, 0x20, 0x74, 0x65, 0x73, 0x74, 0x20, 0x75,
0x73, 0x69, 0x6e, 0x67, 0x20, 0x61, 0x20, 0x6c,
0x61, 0x72, 0x67, 0x65, 0x72, 0x20, 0x74, 0x68,
0x61, 0x6e, 0x20, 0x62, 0x6c, 0x6f, 0x63, 0x6b,
0x2d, 0x73, 0x69, 0x7a, 0x65, 0x20, 0x6b, 0x65,
0x79, 0x20, 0x61, 0x6e, 0x64, 0x20, 0x61, 0x20,
0x6c, 0x61, 0x72, 0x67, 0x65, 0x72, 0x20, 0x74,
0x68, 0x61, 0x6e, 0x20, 0x62, 0x6c, 0x6f, 0x63,
0x6b, 0x2d, 0x73, 0x69, 0x7a, 0x65, 0x20, 0x64,
0x61, 0x74, 0x61, 0x2e, 0x20, 0x54, 0x68, 0x65,
0x20, 0x6b, 0x65, 0x79, 0x20, 0x6e, 0x65, 0x65,
0x64, 0x73, 0x20, 0x74, 0x6f, 0x20, 0x62, 0x65,
0x20, 0x68, 0x61, 0x73, 0x68, 0x65, 0x64, 0x20,
0x62, 0x65, 0x66, 0x6f, 0x72, 0x65, 0x20, 0x62,
0x65, 0x69, 0x6e, 0x67, 0x20, 0x75, 0x73, 0x65,
0x64, 0x20, 0x62, 0x79, 0x20, 0x74, 0x68, 0x65,
0x20, 0x48, 0x4d, 0x41, 0x43, 0x20, 0x61, 0x6c,
0x67, 0x6f, 0x72, 0x69, 0x74, 0x68, 0x6d, 0x2e,
],
output: vec![
0x9b, 0x09, 0xff, 0xa7, 0x1b, 0x94, 0x2f, 0xcb,
0x27, 0x63, 0x5f, 0xbc, 0xd5, 0xb0, 0xe9, 0x44,
0xbf, 0xdc, 0x63, 0x64, 0x4f, 0x07, 0x13, 0x93,
0x8a, 0x7f, 0x51, 0x53, 0x5c, 0x3a, 0x35, 0xe2,
],
},
];
for test in tests {
let mut engine = HmacEngine::<sha256::Hash>::new(&test.key);
engine.input(&test.input);
let hash = Hmac::<sha256::Hash>::from_engine(engine);
assert_eq!(&hash[..], &test.output[..]);
assert_eq!(hash.as_byte_array(), test.output.as_slice());
}
}
#[cfg(feature = "serde")]
#[test]
fn hmac_sha512_serde() {
use serde_test::{assert_tokens, Configure, Token};
use crate::{sha512, Hash, Hmac};
#[rustfmt::skip]
static HASH_BYTES: [u8; 64] = [
0x8b, 0x41, 0xe1, 0xb7, 0x8a, 0xd1, 0x15, 0x21,
0x11, 0x3c, 0x52, 0xff, 0x18, 0x2a, 0x1b, 0x8e,
0x0a, 0x19, 0x57, 0x54, 0xaa, 0x52, 0x7f, 0xcd,
0x00, 0xa4, 0x11, 0x62, 0x0b, 0x46, 0xf2, 0x0f,
0xff, 0xfb, 0x80, 0x88, 0xcc, 0xf8, 0x54, 0x97,
0x12, 0x1a, 0xd4, 0x49, 0x9e, 0x08, 0x45, 0xb8,
0x76, 0xf6, 0xdd, 0x66, 0x40, 0x08, 0x8a, 0x2f,
0x0b, 0x2d, 0x8a, 0x60, 0x0b, 0xdf, 0x4c, 0x0c,
];
let hash = Hmac::<sha512::Hash>::from_slice(&HASH_BYTES).expect("right number of bytes");
assert_tokens(&hash.compact(), &[Token::BorrowedBytes(&HASH_BYTES[..])]);
assert_tokens(
&hash.readable(),
&[Token::Str(
"8b41e1b78ad11521113c52ff182a1b8e0a195754aa527fcd00a411620b46f20f\
fffb8088ccf85497121ad4499e0845b876f6dd6640088a2f0b2d8a600bdf4c0c",
)],
);
}
}
#[cfg(bench)]
mod benches {
use test::Bencher;
use crate::{sha256, Hash, HashEngine, Hmac};
#[bench]
pub fn hmac_sha256_10(bh: &mut Bencher) {
let mut engine = Hmac::<sha256::Hash>::engine();
let bytes = [1u8; 10];
bh.iter(|| {
engine.input(&bytes);
});
bh.bytes = bytes.len() as u64;
}
#[bench]
pub fn hmac_sha256_1k(bh: &mut Bencher) {
let mut engine = Hmac::<sha256::Hash>::engine();
let bytes = [1u8; 1024];
bh.iter(|| {
engine.input(&bytes);
});
bh.bytes = bytes.len() as u64;
}
#[bench]
pub fn hmac_sha256_64k(bh: &mut Bencher) {
let mut engine = Hmac::<sha256::Hash>::engine();
let bytes = [1u8; 65536];
bh.iter(|| {
engine.input(&bytes);
});
bh.bytes = bytes.len() as u64;
}
}