| "+""+(item.is_alias===true?(""+item.alias+" - see "):"")+item.displayPath+""+name+" | "+""+""+item.desc+" |
"+code.outerHTML+" |
fn:) to \
+ restrict the search to a given item kind.","Accepted kinds are: fn, mod, struct, \
+ enum, trait, type, macro, \
+ and const.","Search functions by type signature (e.g., vec -> usize or \
+ * -> vec)","Search multiple things at once by splitting your query with comma (e.g., \
+ str,u8 or String,struct:Vec,test)","You can look for items with an exact name by putting double quotes around \
+ your request: \"string\"","Look for items inside another one by searching for a path: vec::Vec",].map(x=>""+x+"
").join("");var div_infos=document.createElement("div");addClass(div_infos,"infos");div_infos.innerHTML="Error type for ConfigBuilder
+UninitializedField(&'static str)Uninitialized field
+ValidationError(String)Custom validation error
+impl Debug for ConfigBuilderError[src]impl Display for ConfigBuilderError[src]impl Error for ConfigBuilderError[src]pub fn source(&self) -> Option<&(dyn Error + 'static)>1.30.0[src]pub fn backtrace(&self) -> Option<&Backtrace>[src]pub fn description(&self) -> &str1.0.0[src]pub fn cause(&self) -> Option<&dyn Error>1.0.0[src]impl From<String> for ConfigBuilderError[src]impl From<UninitializedFieldError> for ConfigBuilderError[src]impl RefUnwindSafe for ConfigBuilderError[src]impl Send for ConfigBuilderError[src]impl Sync for ConfigBuilderError[src]impl Unpin for ConfigBuilderError[src]impl UnwindSafe for ConfigBuilderError[src]impl<T> Any for T where
T: 'static + ?Sized, [src]impl<T> Borrow<T> for T where
T: ?Sized, [src]impl<T> BorrowMut<T> for T where
T: ?Sized, [src]pub fn borrow_mut(&mut self) -> &mut T[src]impl<T> From<T> for T[src]impl<T, U> Into<U> for T where
U: From<T>, [src]impl<T> Same<T> for Ttype Output = TShould always be Self
impl<T> ToString for T where
T: Display + ?Sized, [src]impl<T, U> TryFrom<U> for T where
U: Into<T>, [src]type Error = InfallibleThe type returned in the event of a conversion error.
+pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>[src]impl<T, U> TryInto<U> for T where
U: TryFrom<T>, [src]Error type for PoWBuilder
+UninitializedField(&'static str)Uninitialized field
+ValidationError(String)Custom validation error
+impl Debug for PoWBuilderError[src]impl Display for PoWBuilderError[src]impl Error for PoWBuilderError[src]pub fn source(&self) -> Option<&(dyn Error + 'static)>1.30.0[src]pub fn backtrace(&self) -> Option<&Backtrace>[src]pub fn description(&self) -> &str1.0.0[src]pub fn cause(&self) -> Option<&dyn Error>1.0.0[src]impl From<String> for PoWBuilderError[src]impl From<UninitializedFieldError> for PoWBuilderError[src]impl RefUnwindSafe for PoWBuilderError[src]impl Send for PoWBuilderError[src]impl Sync for PoWBuilderError[src]impl Unpin for PoWBuilderError[src]impl UnwindSafe for PoWBuilderError[src]impl<T> Any for T where
T: 'static + ?Sized, [src]impl<T> Borrow<T> for T where
T: ?Sized, [src]impl<T> BorrowMut<T> for T where
T: ?Sized, [src]pub fn borrow_mut(&mut self) -> &mut T[src]impl<T> From<T> for T[src]impl<T, U> Into<U> for T where
U: From<T>, [src]impl<T> Same<T> for Ttype Output = TShould always be Self
impl<T> ToString for T where
T: Display + ?Sized, [src]impl<T, U> TryFrom<U> for T where
U: Into<T>, [src]type Error = InfallibleThe type returned in the event of a conversion error.
+pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>[src]impl<T, U> TryInto<U> for T where
U: TryFrom<T>, [src]MCaptch's SHA256 based Proof of Work library
++ use pow_sha256::{ConfigBuilder, PoW}; + + fn main() { + let config = ConfigBuilder::default() + .salt("myrandomsaltisnotlongenoug".into()) + .build() + .unwrap(); + + let phrase = "ironmansucks"; + + const DIFFICULTY: u32 = 1000; + + let work = config.prove_work(&phrase, DIFFICULTY).unwrap(); + assert!(config.is_valid_proof(&work, &phrase)); + assert!(config.is_sufficient_difficulty(&work, DIFFICULTY)); + }
| Config | Configuration for generting proof of work +Please choose a long, unique value for salt +Resistance to dictionary/rainbow attacks depend on uniqueness +of the salt + |
| ConfigBuilder | Builder for |
| PoW | Proof of Work over concrete type T. T can be any type that implements serde::Serialize. + |
| PoWBuilder | Builder for |
| ConfigBuilderError | Error type for ConfigBuilder + |
| PoWBuilderError | Error type for PoWBuilder + |
Configuration for generting proof of work +Please choose a long, unique value for salt +Resistance to dictionary/rainbow attacks depend on uniqueness +of the salt
+salt: Stringimpl Config[src]pub fn prove_work<T>(&self, t: &T, difficulty: u32) -> Result<PoW<T>> where
T: Serialize, [src]Create Proof of Work over item of type T.
+Make sure difficulty is not too high. A 64 bit difficulty, +for example, takes a long time on a general purpose processor. +Returns bincode::Error if serialization fails.
+pub fn prove_work_serialized<T>(&self, prefix: &[u8], difficulty: u32) -> PoW<T> where
T: Serialize, [src]Create Proof of Work on an already serialized item of type T. +The input is assumed to be serialized using network byte order.
+Make sure difficulty is not too high. A 64 bit difficulty, +for example, takes a long time on a general purpose processor.
+pub fn calculate<T>(&self, pow: &PoW<T>, t: &T) -> Result<u128> where
T: Serialize, [src]Calculate the PoW score with the provided input T.
+pub fn calculate_serialized<T>(&self, pow: &PoW<T>, target: &[u8]) -> u128 where
T: Serialize, [src]Calculate the PoW score of an already serialized T and self. +The input is assumed to be serialized using network byte order.
+pub fn is_valid_proof<T>(&self, pow: &PoW<T>, t: &T) -> bool where
T: Serialize, [src]Verifies that the PoW is indeed generated out of the phrase provided.
+pub fn is_sufficient_difficulty<T>(
&self,
pow: &PoW<T>,
target_diff: u32
) -> bool where
T: Serialize, [src]Checks if the PoW result is of sufficient difficulty
+impl Clone for Config[src]impl Debug for Config[src]impl<'de> Deserialize<'de> for Config[src]fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error> where
__D: Deserializer<'de>, [src]impl PartialEq<Config> for Config[src]impl Serialize for Config[src]fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error> where
__S: Serializer, [src]impl StructuralPartialEq for Config[src]impl RefUnwindSafe for Config[src]impl Send for Config[src]impl Sync for Config[src]impl Unpin for Config[src]impl UnwindSafe for Config[src]impl<T> Any for T where
T: 'static + ?Sized, [src]impl<T> Borrow<T> for T where
T: ?Sized, [src]impl<T> BorrowMut<T> for T where
T: ?Sized, [src]pub fn borrow_mut(&mut self) -> &mut T[src]impl<T> DeserializeOwned for T where
T: for<'de> Deserialize<'de>, [src]impl<T> From<T> for T[src]impl<T, U> Into<U> for T where
U: From<T>, [src]impl<T> Same<T> for Ttype Output = TShould always be Self
impl<T> ToOwned for T where
T: Clone, [src]type Owned = TThe resulting type after obtaining ownership.
+pub fn to_owned(&self) -> T[src]pub fn clone_into(&self, target: &mut T)[src]impl<T, U> TryFrom<U> for T where
U: Into<T>, [src]type Error = InfallibleThe type returned in the event of a conversion error.
+pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>[src]impl<T, U> TryInto<U> for T where
U: TryFrom<T>, [src]Builder for Config.
impl ConfigBuilder[src]pub fn salt(&mut self, value: String) -> &mut Self[src]pub fn build(&self) -> Result<Config, ConfigBuilderError>[src]impl Clone for ConfigBuilder[src]fn clone(&self) -> ConfigBuilder[src]pub fn clone_from(&mut self, source: &Self)1.0.0[src]impl Default for ConfigBuilder[src]impl RefUnwindSafe for ConfigBuilder[src]impl Send for ConfigBuilder[src]impl Sync for ConfigBuilder[src]impl Unpin for ConfigBuilder[src]impl UnwindSafe for ConfigBuilder[src]impl<T> Any for T where
T: 'static + ?Sized, [src]impl<T> Borrow<T> for T where
T: ?Sized, [src]impl<T> BorrowMut<T> for T where
T: ?Sized, [src]pub fn borrow_mut(&mut self) -> &mut T[src]impl<T> From<T> for T[src]impl<T, U> Into<U> for T where
U: From<T>, [src]impl<T> Same<T> for Ttype Output = TShould always be Self
impl<T> ToOwned for T where
T: Clone, [src]type Owned = TThe resulting type after obtaining ownership.
+pub fn to_owned(&self) -> T[src]pub fn clone_into(&self, target: &mut T)[src]impl<T, U> TryFrom<U> for T where
U: Into<T>, [src]type Error = InfallibleThe type returned in the event of a conversion error.
+pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>[src]impl<T, U> TryInto<U> for T where
U: TryFrom<T>, [src]Proof of Work over concrete type T. T can be any type that implements serde::Serialize.
+nonce: u64result: Stringimpl<T: Clone> Clone for PoW<T>[src]impl<T: Debug> Debug for PoW<T>[src]impl<'de, T> Deserialize<'de> for PoW<T>[src]fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error> where
__D: Deserializer<'de>, [src]impl<T: PartialEq> PartialEq<PoW<T>> for PoW<T>[src]impl<T> Serialize for PoW<T>[src]fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error> where
__S: Serializer, [src]impl<T> StructuralPartialEq for PoW<T>[src]impl<T> RefUnwindSafe for PoW<T> where
T: RefUnwindSafe, [src]impl<T> Send for PoW<T> where
T: Send, [src]impl<T> Sync for PoW<T> where
T: Sync, [src]impl<T> Unpin for PoW<T> where
T: Unpin, [src]impl<T> UnwindSafe for PoW<T> where
T: UnwindSafe, [src]impl<T> Any for T where
T: 'static + ?Sized, [src]impl<T> Borrow<T> for T where
T: ?Sized, [src]impl<T> BorrowMut<T> for T where
T: ?Sized, [src]pub fn borrow_mut(&mut self) -> &mut T[src]impl<T> DeserializeOwned for T where
T: for<'de> Deserialize<'de>, [src]impl<T> From<T> for T[src]impl<T, U> Into<U> for T where
U: From<T>, [src]impl<T> Same<T> for Ttype Output = TShould always be Self
impl<T> ToOwned for T where
T: Clone, [src]type Owned = TThe resulting type after obtaining ownership.
+pub fn to_owned(&self) -> T[src]pub fn clone_into(&self, target: &mut T)[src]impl<T, U> TryFrom<U> for T where
U: Into<T>, [src]type Error = InfallibleThe type returned in the event of a conversion error.
+pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>[src]impl<T, U> TryInto<U> for T where
U: TryFrom<T>, [src]Builder for PoW.
impl<T: Clone> PoWBuilder<T>[src]pub fn nonce(&mut self, value: u64) -> &mut Self[src]pub fn result(&mut self, value: String) -> &mut Self[src]pub fn build(&self) -> Result<PoW<T>, PoWBuilderError>[src]impl<T: Clone> Clone for PoWBuilder<T>[src]fn clone(&self) -> PoWBuilder<T>[src]pub fn clone_from(&mut self, source: &Self)1.0.0[src]impl<T: Clone> Default for PoWBuilder<T>[src]impl<T> RefUnwindSafe for PoWBuilder<T> where
T: RefUnwindSafe, [src]impl<T> Send for PoWBuilder<T> where
T: Send, [src]impl<T> Sync for PoWBuilder<T> where
T: Sync, [src]impl<T> Unpin for PoWBuilder<T> where
T: Unpin, [src]impl<T> UnwindSafe for PoWBuilder<T> where
T: UnwindSafe, [src]impl<T> Any for T where
T: 'static + ?Sized, [src]impl<T> Borrow<T> for T where
T: ?Sized, [src]impl<T> BorrowMut<T> for T where
T: ?Sized, [src]pub fn borrow_mut(&mut self) -> &mut T[src]impl<T> From<T> for T[src]impl<T, U> Into<U> for T where
U: From<T>, [src]impl<T> Same<T> for Ttype Output = TShould always be Self
impl<T> ToOwned for T where
T: Clone, [src]type Owned = TThe resulting type after obtaining ownership.
+pub fn to_owned(&self) -> T[src]pub fn clone_into(&self, target: &mut T)[src]impl<T, U> TryFrom<U> for T where
U: Into<T>, [src]type Error = InfallibleThe type returned in the event of a conversion error.
+pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>[src]impl<T, U> TryInto<U> for T where
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new file mode 100644
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+//! MCaptch's SHA256 based Proof of Work library +//! +//! # Example: +//! ```rust +//! use pow_sha256::{ConfigBuilder, PoW}; +//! +//! fn main() { +//! let config = ConfigBuilder::default() +//! .salt("myrandomsaltisnotlongenoug".into()) +//! .build() +//! .unwrap(); +//! +//! let phrase = "ironmansucks"; +//! +//! const DIFFICULTY: u32 = 1000; +//! +//! let work = config.prove_work(&phrase, DIFFICULTY).unwrap(); +//! assert!(config.is_valid_proof(&work, &phrase)); +//! assert!(config.is_sufficient_difficulty(&work, DIFFICULTY)); +//! } +//! ``` + +use std::marker::PhantomData; + +use derive_builder::Builder; +use serde::{Deserialize, Serialize}; +use sha2::{Digest, Sha256}; + +/// Proof of Work over concrete type T. T can be any type that implements serde::Serialize. +#[derive(Serialize, Builder, Deserialize, PartialEq, Clone, Debug)] +pub struct PoW<T> { + pub nonce: u64, + pub result: String, + #[builder(default = "PhantomData", setter(skip))] + _spook: PhantomData<T>, +} + +/// Configuration for generting proof of work +/// Please choose a long, unique value for salt +/// Resistance to dictionary/rainbow attacks depend on uniqueness +/// of the salt +#[derive(Serialize, Deserialize, Builder, PartialEq, Clone, Debug)] +pub struct Config { + pub salt: String, +} + +impl Config { + /// Create Proof of Work over item of type T. + /// + /// Make sure difficulty is not too high. A 64 bit difficulty, + /// for example, takes a long time on a general purpose processor. + /// Returns bincode::Error if serialization fails. + pub fn prove_work<T>(&self, t: &T, difficulty: u32) -> bincode::Result<PoW<T>> + where + T: Serialize, + { + bincode::serialize(t).map(|v| self.prove_work_serialized(&v, difficulty)) + } + + /// Create Proof of Work on an already serialized item of type T. + /// The input is assumed to be serialized using network byte order. + /// + /// Make sure difficulty is not too high. A 64 bit difficulty, + /// for example, takes a long time on a general purpose processor. + pub fn prove_work_serialized<T>(&self, prefix: &[u8], difficulty: u32) -> PoW<T> + where + T: Serialize, + { + let prefix_sha = Sha256::new().chain(&self.salt).chain(prefix); + let mut n = 0; + let mut result = 0; + let difficulty = get_difficulty(difficulty); + while result < difficulty { + n += 1; + result = score(prefix_sha.clone(), n); + } + PoW { + nonce: n, + result: result.to_string(), + _spook: PhantomData, + } + } + + /// Calculate the PoW score with the provided input T. + pub fn calculate<T>(&self, pow: &PoW<T>, t: &T) -> bincode::Result<u128> + where + T: Serialize, + { + bincode::serialize(t).map(|v| self.calculate_serialized(pow, &v)) + } + + /// Calculate the PoW score of an already serialized T and self. + /// The input is assumed to be serialized using network byte order. + pub fn calculate_serialized<T>(&self, pow: &PoW<T>, target: &[u8]) -> u128 + where + T: Serialize, + { + score(Sha256::new().chain(&self.salt).chain(target), pow.nonce) + } + + /// Verifies that the PoW is indeed generated out of the phrase provided. + pub fn is_valid_proof<T>(&self, pow: &PoW<T>, t: &T) -> bool + where + T: Serialize, + { + match self.calculate(pow, t) { + Ok(res) => { + return if pow.result == res.to_string() { + true + } else { + false + } + } + Err(_) => return false, + } + } + + /// Checks if the PoW result is of sufficient difficulty + pub fn is_sufficient_difficulty<T>(&self, pow: &PoW<T>, target_diff: u32) -> bool + where + T: Serialize, + { + match pow.result.parse::<u128>() { + Ok(res) => return res >= get_difficulty(target_diff), + Err(_) => return false, + } + } +} + +fn score(prefix_sha: Sha256, nonce: u64) -> u128 { + first_bytes_as_u128( + prefix_sha + .chain(&nonce.to_be_bytes()) // to_be_bytes() converts to network endian + .finalize() + .as_slice(), + ) +} + +/// # Panics +/// +/// panics if inp.len() < 16 +fn first_bytes_as_u128(inp: &[u8]) -> u128 { + use bincode::config::*; + DefaultOptions::new() + .with_fixint_encoding() + .allow_trailing_bytes() + .with_no_limit() + .with_big_endian() + .deserialize(&inp) + .unwrap() +} + +// utility function to get u128 difficulty factor from u32 +// javacript isn't capable of represnting u128 so +fn get_difficulty(difficulty_factor: u32) -> u128 { + u128::max_value() - u128::max_value() / difficulty_factor as u128 +} + +#[cfg(test)] +mod test { + use super::*; + + const DIFFICULTY: u32 = 1000; + + fn get_config() -> Config { + ConfigBuilder::default() + .salt( + "79ziepia7vhjgviiwjhnend3ofjqocsi2winc4ptqhmkvcajihywxcizewvckg9h6gs4j83v9".into(), + ) + .build() + .unwrap() + } + + #[test] + fn base_functionality() { + // Let's prove we did work targeting a phrase. + let phrase = b"Ex nihilo nihil fit.".to_vec(); + let config = get_config(); + let pw = config.prove_work(&phrase, DIFFICULTY).unwrap(); + assert!(config.calculate(&pw, &phrase).unwrap() >= get_difficulty(DIFFICULTY)); + assert!(config.is_valid_proof(&pw, &phrase)); + assert!(config.is_sufficient_difficulty(&pw, DIFFICULTY)); + } + + #[test] + fn double_pow() { + let phrase = "Ex nihilo nihil fit.".to_owned(); + let config = get_config(); + + let pw = config.prove_work(&phrase, DIFFICULTY).unwrap(); + let pwpw = config.prove_work(&pw, DIFFICULTY).unwrap(); + + assert!(config.calculate(&pw, &phrase).unwrap() >= get_difficulty(DIFFICULTY)); + assert!(config.is_valid_proof(&pw, &phrase)); + assert!(config.is_sufficient_difficulty(&pw, DIFFICULTY)); + + assert!(config.calculate(&pwpw, &pw).unwrap() >= get_difficulty(DIFFICULTY)); + assert!(config.is_valid_proof(&pwpw, &pw)); + assert!(config.is_sufficient_difficulty(&pwpw, DIFFICULTY)); + } + + #[test] + fn is_not_valid_proof() { + let phrase = "Ex nihilo nihil fit.".to_owned(); + let phrase2 = "Omne quod movetur ab alio movetur.".to_owned(); + + let config = get_config(); + let pw = config.prove_work(&phrase, DIFFICULTY).unwrap(); + + let pw2 = config.prove_work(&phrase2, DIFFICULTY).unwrap(); + + assert!(!config.is_valid_proof(&pw, &phrase2)); + assert!(!config.is_valid_proof(&pw2, &phrase)); + } + + #[test] + fn serialization_test() { + let target: u8 = 1; + let config = get_config(); + let pw = config.prove_work(&target, DIFFICULTY).unwrap(); + + let message: (u8, PoW<u8>) = (target, pw); + let message_ser = bincode::serialize(&message).unwrap(); + let recieved_message: (u8, PoW<u8>) = bincode::deserialize(&message_ser).unwrap(); + assert_eq!(recieved_message, message); + assert!(config.is_sufficient_difficulty(&message.1, DIFFICULTY)); + assert!(config.is_valid_proof(&message.1, &target)); + } +} +