miden_crypto/utils/
mod.rsuse alloc::string::String;
use core::fmt::{self, Display, Write};
use super::Word;
mod kv_map;
pub use winter_utils::{
uninit_vector, ByteReader, ByteWriter, Deserializable, DeserializationError, Serializable,
SliceReader,
};
pub mod collections {
pub use super::kv_map::*;
}
pub fn word_to_hex(w: &Word) -> Result<String, fmt::Error> {
let mut s = String::new();
for byte in w.iter().flat_map(|e| e.to_bytes()) {
write!(s, "{byte:02x}")?;
}
Ok(s)
}
pub fn bytes_to_hex_string<const N: usize>(data: [u8; N]) -> String {
let mut s = String::with_capacity(N + 2);
s.push_str("0x");
for byte in data.iter() {
write!(s, "{byte:02x}").expect("formatting hex failed");
}
s
}
#[derive(Debug)]
pub enum HexParseError {
InvalidLength { expected: usize, actual: usize },
MissingPrefix,
InvalidChar,
OutOfRange,
}
impl Display for HexParseError {
fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
match self {
HexParseError::InvalidLength { expected, actual } => {
write!(f, "Expected hex data to have length {expected}, including the 0x prefix. Got {actual}")
},
HexParseError::MissingPrefix => {
write!(f, "Hex encoded data must start with 0x prefix")
},
HexParseError::InvalidChar => {
write!(f, "Hex encoded data must contain characters [a-zA-Z0-9]")
},
HexParseError::OutOfRange => {
write!(f, "Hex encoded values of an RpoDigest must be inside the field modulus")
},
}
}
}
#[cfg(feature = "std")]
impl std::error::Error for HexParseError {}
pub fn hex_to_bytes<const N: usize>(value: &str) -> Result<[u8; N], HexParseError> {
let expected: usize = (N * 2) + 2;
if value.len() != expected {
return Err(HexParseError::InvalidLength { expected, actual: value.len() });
}
if !value.starts_with("0x") {
return Err(HexParseError::MissingPrefix);
}
let mut data = value.bytes().skip(2).map(|v| match v {
b'0'..=b'9' => Ok(v - b'0'),
b'a'..=b'f' => Ok(v - b'a' + 10),
b'A'..=b'F' => Ok(v - b'A' + 10),
_ => Err(HexParseError::InvalidChar),
});
let mut decoded = [0u8; N];
for byte in decoded.iter_mut() {
let high: u8 = data.next().unwrap()?;
let low: u8 = data.next().unwrap()?;
*byte = (high << 4) + low;
}
Ok(decoded)
}