refactor(blocks): use sha256

7 files changed, 177 insertions, 59 deletions

diff --git a/Cargo.lock b/Cargo.lock
index bebdc38..729212d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3,13 +3,35 @@
 version = 4
 
 [[package]]
+name = "bincode"
+version = "2.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "36eaf5d7b090263e8150820482d5d93cd964a81e4019913c972f4edcc6edb740"
+dependencies = [
+ "bincode_derive",
+ "serde",
+ "unty",
+]
+
+[[package]]
+name = "bincode_derive"
+version = "2.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bf95709a440f45e986983918d0e8a1f30a9b1df04918fc828670606804ac3c09"
+dependencies = [
+ "virtue",
+]
+
+[[package]]
 name = "bitcoin"
 version = "0.1.0"
 dependencies = [
+ "bincode",
  "futures",
  "rand",
  "serde",
  "serde_json",
+ "sha2",
  "tokio",
  "tokio-serde",
  "tokio-util",
@@ -22,6 +44,15 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "812e12b5285cc515a9c72a5c1d3b6d46a19dac5acfef5265968c166106e31dd3"
 
 [[package]]
+name = "block-buffer"
+version = "0.10.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3078c7629b62d3f0439517fa394996acacc5cbc91c5a20d8c658e77abd503a71"
+dependencies = [
+ "generic-array",
+]
+
+[[package]]
 name = "bytes"
 version = "1.10.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -34,6 +65,35 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9330f8b2ff13f34540b44e946ef35111825727b38d33286ef986142615121801"
 
 [[package]]
+name = "cpufeatures"
+version = "0.2.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "59ed5838eebb26a2bb2e58f6d5b5316989ae9d08bab10e0e6d103e656d1b0280"
+dependencies = [
+ "libc",
+]
+
+[[package]]
+name = "crypto-common"
+version = "0.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1bfb12502f3fc46cca1bb51ac28df9d618d813cdc3d2f25b9fe775a34af26bb3"
+dependencies = [
+ "generic-array",
+ "typenum",
+]
+
+[[package]]
+name = "digest"
+version = "0.10.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9ed9a281f7bc9b7576e61468ba615a66a5c8cfdff42420a70aa82701a3b1e292"
+dependencies = [
+ "block-buffer",
+ "crypto-common",
+]
+
+[[package]]
 name = "educe"
 version = "0.5.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -155,6 +215,16 @@ dependencies = [
 ]
 
 [[package]]
+name = "generic-array"
+version = "0.14.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4bb6743198531e02858aeaea5398fcc883e71851fcbcb5a2f773e2fb6cb1edf2"
+dependencies = [
+ "typenum",
+ "version_check",
+]
+
+[[package]]
 name = "getrandom"
 version = "0.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -386,6 +456,17 @@ dependencies = [
 ]
 
 [[package]]
+name = "sha2"
+version = "0.10.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a7507d819769d01a365ab707794a4084392c824f54a7a6a7862f8c3d0892b283"
+dependencies = [
+ "cfg-if",
+ "cpufeatures",
+ "digest",
+]
+
+[[package]]
 name = "signal-hook-registry"
 version = "1.4.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -484,12 +565,36 @@ dependencies = [
 ]
 
 [[package]]
+name = "typenum"
+version = "1.19.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "562d481066bde0658276a35467c4af00bdc6ee726305698a55b86e61d7ad82bb"
+
+[[package]]
 name = "unicode-ident"
 version = "1.0.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f63a545481291138910575129486daeaf8ac54aee4387fe7906919f7830c7d9d"
 
 [[package]]
+name = "unty"
+version = "0.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6d49784317cd0d1ee7ec5c716dd598ec5b4483ea832a2dced265471cc0f690ae"
+
+[[package]]
+name = "version_check"
+version = "0.9.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0b928f33d975fc6ad9f86c8f283853ad26bdd5b10b7f1542aa2fa15e2289105a"
+
+[[package]]
+name = "virtue"
+version = "0.0.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "051eb1abcf10076295e815102942cc58f9d5e3b4560e46e53c21e8ff6f3af7b1"
+
+[[package]]
 name = "wasi"
 version = "0.11.1+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/Cargo.toml b/Cargo.toml
index 7343510..6367695 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -11,3 +11,5 @@ tokio-serde = { version = "0.9.0", features = ["json"] }
 tokio-util = { version = "0.7.16", features = ["codec"] }
 futures = "0.3.31"
 rand = "0.9.2"
+sha2 = "0.10.9"
+bincode = "2.0.1"
diff --git a/src/blocks.rs b/src/blocks.rs
index 1fa8486..17e6d4f 100644
--- a/src/blocks.rs
+++ b/src/blocks.rs
@@ -1,5 +1,7 @@
+use bincode::Encode;
+use sha2::{Digest, Sha256, digest::DynDigest};
 use std::{
-    hash::{DefaultHasher, Hash, Hasher},
+    hash::{Hash, Hasher},
     ops::Deref,
 };
 
@@ -7,68 +9,69 @@ use serde::{Deserialize, Serialize};
 
 use crate::{ZERO_PREFIX_AMOUNT, transaction::Transaction};
 
-#[derive(Deserialize, Serialize, Clone, Copy, PartialEq)]
+pub trait CryptoDigest {
+    fn digest(&self, state: &mut impl DynDigest);
+}
+
+#[derive(Deserialize, Serialize, Clone, PartialEq, Encode)]
 pub struct Block {
-    pub prev_hash: u64,
+    pub prev_hash: Vec<u8>,
     pub trans: Transaction,
-    pub pow: Option<u64>,
+    pub pow: Vec<u8>,
 }
 
 impl Block {
-    fn new(prev_hash: Option<u64>, trans: Transaction) -> Self {
+    fn new(prev_hash: Option<&[u8]>, trans: Transaction) -> Self {
         Self {
-            prev_hash: prev_hash.unwrap_or(0), // special blocks
+            prev_hash: prev_hash
+                .unwrap_or(&[])
+                .to_vec(), // special blocks
             trans,
-            pow: None,
+            pow: Vec::default(),
         }
     }
 
-    fn calc_pow(&self) -> u64 {
+    fn pref_zeros(hashed: &[u8]) -> Result<usize, usize> {
+        hashed
+            .iter()
+            .try_fold(0, |nonce, x| {
+                if nonce >= ZERO_PREFIX_AMOUNT {
+                    Ok(nonce)
+                } else if *x == 0 {
+                    Ok(nonce + 1)
+                } else {
+                    Err(nonce)
+                }
+            })
+    }
+
+    fn calc_pow(&self) -> Vec<u8> {
         for i in 0.. {
             // reset every loop
-            let mut hasher = DefaultHasher::new();
-            (&self.prev_hash, &self.trans, i).hash(&mut hasher);
-            let hashed = hasher.finish();
-            if hashed
-                .to_string()
-                .starts_with(
-                    &"0".repeat(ZERO_PREFIX_AMOUNT)
-                        .to_string(),
-                )
-            {
-                return hashed;
+            let mut hasher = Sha256::new();
+            Digest::update(&mut hasher, bincode::encode_to_vec((&self.prev_hash, &self.trans, i), bincode::config::standard()).unwrap());
+            let hashed = hasher.finalize();
+            if Self::pref_zeros(&hashed).is_ok() {
+                return hashed.to_vec();
             }
         }
         unreachable!()
     }
 
     pub fn verify_pow(&mut self) -> bool {
-        let mut hasher = DefaultHasher::new();
-        self.hash(&mut hasher);
-        hasher
-            .finish()
-            .to_string()
-            .to_string()
-            .starts_with(
-                &"0".repeat(ZERO_PREFIX_AMOUNT)
-                    .to_string(),
-            )
+        let mut hasher = Sha256::new();
+        Digest::update(&mut hasher, bincode::encode_to_vec(&*self, bincode::config::standard()).unwrap());
+        Self::pref_zeros(&hasher.finalize()).is_ok()
     }
 
     pub fn calc_set_pow(&mut self) {
-        self.pow = Some(self.calc_pow());
+        self.pow = self.calc_pow();
     }
 }
 
-impl Hash for Block {
-    fn hash<H: Hasher>(&self, state: &mut H) {
-        self.prev_hash
-            .hash(state);
-        self.trans
-            .hash(state);
-        self.pow
-            .expect("Cannot hash whole block with no PoW")
-            .hash(state);
+impl CryptoDigest for Block {
+    fn digest(&self, state: &mut impl DynDigest) {
+        state.update(&bincode::encode_to_vec((&self.prev_hash, &self.trans, &self.pow), bincode::config::standard()).unwrap());
     }
 }
 
@@ -85,16 +88,17 @@ impl BlockChain {
     }
 
     pub fn new_block(&self, trans: Transaction) -> Block {
-        let mut hasher = DefaultHasher::new();
-        Block::new(
-            self.blocks
-                .last()
-                .map(|b| {
-                    b.hash(&mut hasher);
-                    hasher.finish()
-                }),
-            trans,
-        )
+        let mut hasher = Sha256::new();
+        let prev = self
+            .blocks
+            .last();
+        let prev_hash = if let Some(b) = prev {
+            b.digest(&mut hasher);
+            Some(&*hasher.finalize())
+        } else {
+            None
+        };
+        Block::new(prev_hash, trans)
     }
 
     pub fn store(&mut self, block: Block) {
@@ -106,6 +110,7 @@ impl BlockChain {
 
 impl Deref for BlockChain {
     type Target = Vec<Block>;
+
     fn deref(&self) -> &Self::Target {
         &self.blocks
     }
diff --git a/src/client.rs b/src/client.rs
index 457a70d..eb417fd 100644
--- a/src/client.rs
+++ b/src/client.rs
@@ -1,7 +1,8 @@
+use bincode::Encode;
 use rand::Rng;
 use serde::{Deserialize, Serialize};
 
-#[derive(Hash, Deserialize, Serialize, Clone, Copy, PartialEq)]
+#[derive(Hash, Deserialize, Serialize, Clone, Copy, PartialEq, Encode)]
 pub struct Client {
     id: u32,
 }
diff --git a/src/lib.rs b/src/lib.rs
index 0545aa5..9cdbdcd 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -6,4 +6,4 @@ pub mod client;
 
 pub mod network;
 
-const ZERO_PREFIX_AMOUNT: usize = 5; // TODO: make this dynamic
+const ZERO_PREFIX_AMOUNT: usize = 2; // TODO: make this dynamic
diff --git a/src/network.rs b/src/network.rs
index 753f743..c18ae07 100644
--- a/src/network.rs
+++ b/src/network.rs
@@ -75,7 +75,7 @@ impl Network {
         let peer = Arc::new(Mutex::new(Peer::new(
             self.this
                 .clone(),
-            TcpStream::connect("192.168.143.90:6767")
+            TcpStream::connect("192.168.1.16:6767")
                 .await
                 .unwrap(),
         )));
@@ -222,8 +222,11 @@ impl Peer {
 
     async fn handle(parent: Weak<Mutex<Network>>, req: Request) {
         match req {
-            Request::Block(mut block) => match block.pow {
-                Some(_pow) => {
+            Request::Block(mut block) => {
+                if !block
+                    .pow
+                    .is_empty()
+                {
                     if !block.verify_pow() {
                         eprintln!("Rejecting remote block, POW verification failed"); // TODO: log remote IP
                         return;
@@ -237,8 +240,8 @@ impl Peer {
                         .lock()
                         .await
                         .store(block)
-                }
-                None => {
+                } else {
+                    print!("as");
                     block.calc_set_pow();
                     let parent = parent
                         .upgrade()
@@ -250,7 +253,7 @@ impl Peer {
                         .broadcast(Request::Block(block))
                         .await;
                 }
-            },
+            }
             Request::Ibd(bc) => match bc {
                 Some(bc) => {
                     let parent = parent
@@ -267,10 +270,11 @@ impl Peer {
                         || (self_bc
                             .blocks
                             .iter()
+                            // TODO: Optimize via try_fold
                             .fold(true, |i, b| {
                                 if i {
                                     b.pow
-                                        .is_none()
+                                        .is_empty()
                                 } else {
                                     false
                                 }
diff --git a/src/transaction.rs b/src/transaction.rs
index dcaff49..760f080 100644
--- a/src/transaction.rs
+++ b/src/transaction.rs
@@ -1,8 +1,9 @@
+use bincode::Encode;
 use serde::{Deserialize, Serialize};
 
 use crate::client::Client;
 
-#[derive(Hash, Deserialize, Serialize, Clone, Copy, PartialEq)]
+#[derive(Hash, Deserialize, Serialize, Clone, Copy, PartialEq, Encode)]
 pub struct Transaction {
     from: Client,
     to: Client,