use my own key exchange (diffie hellman) crate :D

Cargo.lock

@@ -3,54 +3,16 @@
 version = 4
 
 [[package]]
-name = "anstream"
+name = "arrayref"
-version = "0.6.21"
+version = "0.3.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "43d5b281e737544384e969a5ccad3f1cdd24b48086a0fc1b2a5262a26b8f4f4a"
+checksum = "76a2e8124351fda1ef8aaaa3bbd7ebbcb486bbcd4225aca0aa0d84bb2db8fecb"
-dependencies = [
- "anstyle",
- "anstyle-parse",
- "anstyle-query",
- "anstyle-wincon",
- "colorchoice",
- "is_terminal_polyfill",
- "utf8parse",
-]
 
 [[package]]
-name = "anstyle"
+name = "arrayvec"
-version = "1.0.13"
+version = "0.7.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5192cca8006f1fd4f7237516f40fa183bb07f8fbdfedaa0036de5ea9b0b45e78"
+checksum = "7c02d123df017efcdfbd739ef81735b36c5ba83ec3c59c80a9d7ecc718f92e50"
-
-[[package]]
-name = "anstyle-parse"
-version = "0.2.7"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4e7644824f0aa2c7b9384579234ef10eb7efb6a0deb83f9630a49594dd9c15c2"
-dependencies = [
- "utf8parse",
-]
-
-[[package]]
-name = "anstyle-query"
-version = "1.1.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9e231f6134f61b71076a3eab506c379d4f36122f2af15a9ff04415ea4c3339e2"
-dependencies = [
- "windows-sys",
-]
-
-[[package]]
-name = "anstyle-wincon"
-version = "3.0.10"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3e0633414522a32ffaac8ac6cc8f748e090c5717661fddeea04219e2344f5f2a"
-dependencies = [
- "anstyle",
- "once_cell_polyfill",
- "windows-sys",
-]
 
 [[package]]
 name = "autocfg"
@@ -58,6 +20,29 @@ version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c08606f8c3cbf4ce6ec8e28fb0014a2c086708fe954eaa885384a6165172e7e8"
 
+[[package]]
+name = "blake3"
+version = "1.8.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3888aaa89e4b2a40fca9848e400f6a658a5a3978de7be858e209cafa8be9a4a0"
+dependencies = [
+ "arrayref",
+ "arrayvec",
+ "cc",
+ "cfg-if",
+ "constant_time_eq",
+]
+
+[[package]]
+name = "cc"
+version = "1.2.44"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "37521ac7aabe3d13122dc382493e20c9416f299d2ccd5b3a5340a2570cdeb0f3"
+dependencies = [
+ "find-msvc-tools",
+ "shlex",
+]
+
 [[package]]
 name = "cfg-if"
 version = "1.0.3"
@@ -67,106 +52,36 @@ checksum = "2fd1289c04a9ea8cb22300a459a72a385d7c73d3259e2ed7dcb2af674838cfa9"
 [[package]]
 name = "chacha"
 version = "0.1.0"
-dependencies = [
- "clap",
- "clap-num",
-]
 
 [[package]]
-name = "clap"
+name = "constant_time_eq"
-version = "4.5.48"
+version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e2134bb3ea021b78629caa971416385309e0131b351b25e01dc16fb54e1b5fae"
+checksum = "7c74b8349d32d297c9134b8c88677813a227df8f779daa29bfc29c183fe3dca6"
-dependencies = [
- "clap_builder",
- "clap_derive",
-]
 
 [[package]]
-name = "clap-num"
+name = "crypto-bigint"
-version = "1.2.0"
+version = "0.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "822c4000301ac390e65995c62207501e3ef800a1fc441df913a5e8e4dc374816"
+checksum = "96272c2ff28b807e09250b180ad1fb7889a3258f7455759b5c3c58b719467130"
 dependencies = [
  "num-traits",
-]
+ "rand_core 0.6.4",
-
-[[package]]
-name = "clap_builder"
-version = "4.5.48"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c2ba64afa3c0a6df7fa517765e31314e983f51dda798ffba27b988194fb65dc9"
-dependencies = [
- "anstream",
- "anstyle",
- "clap_lex",
- "strsim",
-]
-
-[[package]]
-name = "clap_derive"
-version = "4.5.47"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bbfd7eae0b0f1a6e63d4b13c9c478de77c2eb546fba158ad50b4203dc24b9f9c"
-dependencies = [
- "heck",
- "proc-macro2",
- "quote",
- "syn",
-]
-
-[[package]]
-name = "clap_lex"
-version = "0.7.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b94f61472cee1439c0b966b47e3aca9ae07e45d070759512cd390ea2bebc6675"
-
-[[package]]
-name = "colorchoice"
-version = "1.0.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b05b61dc5112cbb17e4b6cd61790d9845d13888356391624cbe7e41efeac1e75"
-
-[[package]]
-name = "cpufeatures"
-version = "0.2.17"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "59ed5838eebb26a2bb2e58f6d5b5316989ae9d08bab10e0e6d103e656d1b0280"
-dependencies = [
- "libc",
-]
-
-[[package]]
-name = "curve25519-dalek"
-version = "4.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "97fb8b7c4503de7d6ae7b42ab72a5a59857b4c937ec27a3d4539dba95b5ab2be"
-dependencies = [
- "cfg-if",
- "cpufeatures",
- "curve25519-dalek-derive",
- "fiat-crypto",
- "rustc_version",
  "subtle",
- "zeroize",
 ]
 
 [[package]]
-name = "curve25519-dalek-derive"
+name = "diffie-hellman"
-version = "0.1.1"
+version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f46882e17999c6cc590af592290432be3bce0428cb0d5f8b6715e4dc7b383eb3"
 dependencies = [
- "proc-macro2",
+ "crypto-bigint",
- "quote",
- "syn",
 ]
 
 [[package]]
-name = "fiat-crypto"
+name = "find-msvc-tools"
-version = "0.2.9"
+version = "0.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "28dea519a9695b9977216879a3ebfddf92f1c08c05d984f8996aecd6ecdc811d"
+checksum = "52051878f80a721bb68ebfbc930e07b65ba72f2da88968ea5c06fd6ca3d3a127"
 
 [[package]]
 name = "getrandom"
@@ -191,27 +106,16 @@ dependencies = [
  "wasi 0.14.7+wasi-0.2.4",
 ]
 
-[[package]]
-name = "heck"
-version = "0.5.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2304e00983f87ffb38b55b444b5e3b60a884b5d30c0fca7d82fe33449bbe55ea"
-
 [[package]]
 name = "hermes"
 version = "0.1.0"
 dependencies = [
+ "blake3",
  "chacha",
+ "diffie-hellman",
  "rand",
- "x25519-dalek",
 ]
 
-[[package]]
-name = "is_terminal_polyfill"
-version = "1.70.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7943c866cc5cd64cbc25b2e01621d07fa8eb2a1a23160ee81ce38704e97b8ecf"
-
 [[package]]
 name = "libc"
 version = "0.2.176"
@@ -227,12 +131,6 @@ dependencies = [
  "autocfg",
 ]
 
-[[package]]
-name = "once_cell_polyfill"
-version = "1.70.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a4895175b425cb1f87721b59f0f286c2092bd4af812243672510e1ac53e2e0ad"
-
 [[package]]
 name = "ppv-lite86"
 version = "0.2.21"
@@ -305,55 +203,10 @@ dependencies = [
 ]
 
 [[package]]
-name = "rustc_version"
+name = "shlex"
-version = "0.4.1"
+version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cfcb3a22ef46e85b45de6ee7e79d063319ebb6594faafcf1c225ea92ab6e9b92"
+checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
-dependencies = [
- "semver",
-]
-
-[[package]]
-name = "semver"
-version = "1.0.27"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d767eb0aabc880b29956c35734170f26ed551a859dbd361d140cdbeca61ab1e2"
-
-[[package]]
-name = "serde"
-version = "1.0.228"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9a8e94ea7f378bd32cbbd37198a4a91436180c5bb472411e48b5ec2e2124ae9e"
-dependencies = [
- "serde_core",
- "serde_derive",
-]
-
-[[package]]
-name = "serde_core"
-version = "1.0.228"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "41d385c7d4ca58e59fc732af25c3983b67ac852c1a25000afe1175de458b67ad"
-dependencies = [
- "serde_derive",
-]
-
-[[package]]
-name = "serde_derive"
-version = "1.0.228"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d540f220d3187173da220f885ab66608367b6574e925011a9353e4badda91d79"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn",
-]
-
-[[package]]
-name = "strsim"
-version = "0.11.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7da8b5736845d9f2fcb837ea5d9e2628564b3b043a70948a3f0b778838c5fb4f"
 
 [[package]]
 name = "subtle"
@@ -378,12 +231,6 @@ version = "1.0.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f63a545481291138910575129486daeaf8ac54aee4387fe7906919f7830c7d9d"
 
-[[package]]
-name = "utf8parse"
-version = "0.2.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "06abde3611657adf66d383f00b093d7faecc7fa57071cce2578660c9f1010821"
-
 [[package]]
 name = "wasi"
 version = "0.11.1+wasi-snapshot-preview1"
@@ -408,104 +255,12 @@ dependencies = [
  "wit-bindgen",
 ]
 
-[[package]]
-name = "windows-link"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "45e46c0661abb7180e7b9c281db115305d49ca1709ab8242adf09666d2173c65"
-
-[[package]]
-name = "windows-sys"
-version = "0.60.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f2f500e4d28234f72040990ec9d39e3a6b950f9f22d3dba18416c35882612bcb"
-dependencies = [
- "windows-targets",
-]
-
-[[package]]
-name = "windows-targets"
-version = "0.53.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2d42b7b7f66d2a06854650af09cfdf8713e427a439c97ad65a6375318033ac4b"
-dependencies = [
- "windows-link",
- "windows_aarch64_gnullvm",
- "windows_aarch64_msvc",
- "windows_i686_gnu",
- "windows_i686_gnullvm",
- "windows_i686_msvc",
- "windows_x86_64_gnu",
- "windows_x86_64_gnullvm",
- "windows_x86_64_msvc",
-]
-
-[[package]]
-name = "windows_aarch64_gnullvm"
-version = "0.53.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "86b8d5f90ddd19cb4a147a5fa63ca848db3df085e25fee3cc10b39b6eebae764"
-
-[[package]]
-name = "windows_aarch64_msvc"
-version = "0.53.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c7651a1f62a11b8cbd5e0d42526e55f2c99886c77e007179efff86c2b137e66c"
-
-[[package]]
-name = "windows_i686_gnu"
-version = "0.53.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c1dc67659d35f387f5f6c479dc4e28f1d4bb90ddd1a5d3da2e5d97b42d6272c3"
-
-[[package]]
-name = "windows_i686_gnullvm"
-version = "0.53.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9ce6ccbdedbf6d6354471319e781c0dfef054c81fbc7cf83f338a4296c0cae11"
-
-[[package]]
-name = "windows_i686_msvc"
-version = "0.53.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "581fee95406bb13382d2f65cd4a908ca7b1e4c2f1917f143ba16efe98a589b5d"
-
-[[package]]
-name = "windows_x86_64_gnu"
-version = "0.53.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2e55b5ac9ea33f2fc1716d1742db15574fd6fc8dadc51caab1c16a3d3b4190ba"
-
-[[package]]
-name = "windows_x86_64_gnullvm"
-version = "0.53.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0a6e035dd0599267ce1ee132e51c27dd29437f63325753051e71dd9e42406c57"
-
-[[package]]
-name = "windows_x86_64_msvc"
-version = "0.53.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "271414315aff87387382ec3d271b52d7ae78726f5d44ac98b4f4030c91880486"
-
 [[package]]
 name = "wit-bindgen"
 version = "0.46.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f17a85883d4e6d00e8a97c586de764dabcc06133f7f1d55dce5cdc070ad7fe59"
 
-[[package]]
-name = "x25519-dalek"
-version = "2.0.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c7e468321c81fb07fa7f4c636c3972b9100f0346e5b6a9f2bd0603a52f7ed277"
-dependencies = [
- "curve25519-dalek",
- "rand_core 0.6.4",
- "serde",
- "zeroize",
-]
-
 [[package]]
 name = "zerocopy"
 version = "0.8.27"
@@ -525,23 +280,3 @@ dependencies = [
  "quote",
  "syn",
 ]
-
-[[package]]
-name = "zeroize"
-version = "1.8.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b97154e67e32c85465826e8bcc1c59429aaaf107c1e4a9e53c8d8ccd5eff88d0"
-dependencies = [
- "zeroize_derive",
-]
-
-[[package]]
-name = "zeroize_derive"
-version = "1.4.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ce36e65b0d2999d2aafac989fb249189a141aee1f53c612c1f37d72631959f69"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn",
-]

Cargo.toml

@@ -4,6 +4,7 @@ version = "0.1.0"
 edition = "2024"
 
 [dependencies]
-x25519-dalek = { version = "2", features = ["getrandom"] }
+diffie-hellman = { path = "../diffie-hellman", features = ["rand"] }
 chacha = { path = "../chacha" }
 rand = "0.9.2"
+blake3 = "1.8.2"

README.md

@@ -0,0 +1,26 @@
+# Hermes
+i mek protokol (pls don't guillotine me, is for fun)
+
+## bad things (*that i should really fix*)
+- no verification of authenticity
+  - [ ] message/MAC ([poly1305](https://en.wikipedia.org/wiki/Poly1305)?)
+  - [ ] server/client (static keys)
+- protocol structure
+  - [ ] how to prevent nonce reuse/how to get shared nonce? (current version uses one nonce for the entire connection :P)
+    - pseudorandom function? (but how would you seed it??? shared key?)
+      - you would need to seed it with something else than *just* the shared key, or else the output would be completely predictable and an attacker could easily decrypt all your traffic if they manage to get the secret key (if they get the secret key, then your data is probably screwed anyways). however, if the nonce is ephemeral (not saved), and reasonably unpredictable for an attacker, then that would mean they would have to search up to $2^{96}$ blocks in order to get the data. its *nothing* compared to the secret key ($2^{256}$), and it is *not* where the security of the protocol or the chacha stream cipher should be derived.
+      - seeding it with the mac or using the hash of the previous message(s) would mean that if they were to replay or repeat the same message blocks, then an attacker would be able to see the same pattern of messages. it would also make it vulnerable to replay attacks, where an attacker could replay a message to the server, given that they somehow know the same nonce is reused. 
+      - the benefit of depending on some other method that would produce the same results on each end is that a malicious user would be unable to send a bogus nonce that has already been used. may not be a problem, since the server shouldn't send information that is so sensitive that the client sharing it with a third party would be detrimental for the server. 
+    - in message header (would mean ~~a lot more~~ *a bit more* (12 bytes isn't that much, and it's probably not wise to prematurely optimize it away) data being sent)
+      - should it be public? or should it be sent encrypted with prev. msg?
+      - having it public wouldn't be the end of the world, but if it were, an attacker would know when two blocks are encrypted with the same nonce. the chance of two nonces being the same is $2^{-96}$, so it's not exactly something to be scared of. 
+      - better to rely on `/dev/urandom` made by people who actually know their shit and who do have experience (also isn't based on my arbitrary schemes; keep it simple stupid (unless you have a very good reason not to))
+    - based on message content/MAC? hashing???
+      - eh, not that effective at preventing nonce reuse
+- [ ] no fucking tests (dummy servers and clients?)
+  - how tf would i know if i break something???
+  - except for manually testing ofc.
+
+## things that would be sick but also idk if i have the time or willpower before my attention gets taken by other shit i really want to do like implementing a post-quantum secure KEM (maybe KYBER..)
+- [ ] custom blake3 implementation (~ *IM NOT A BIG FAN OF THE GOVERNMENT* ~)
+- [ ] custom poly1305 implementation (it would be fine to use one from `crates.io`, but it would *be so awesome, it would be so cool* if i made it myself :D + fun)

src/lib.rs

@@ -1,106 +1,85 @@
 use chacha::Block;
+use diffie_hellman::{Public, Secret};
+use rand::{RngCore, rng};
 use std::io::{Error, Read, Write};
 use std::net::{Shutdown, TcpStream};
-use rand::{rng, RngCore};
-use x25519_dalek::{EphemeralSecret, PublicKey};
 
 #[inline]
 fn u8_to_u32(to: &mut [u32], from: &[u8]) {
     for i in 0..to.len() {
-        to[i] = u32::from_le_bytes(from[4*i..][..4].try_into().unwrap());
+        to[i] = u32::from_le_bytes(from[4 * i..][..4].try_into().unwrap());
     }
 }
 
-/*
-#[repr(u8)]
-enum Exchange {
-    DHCurve25519 = 0
-}
-
-impl TryFrom<u8> for Exchange {
-    type Error = Error;
-
-    fn try_from(value: u8) -> Result<Self, Self::Error> {
-        match value {
-            0 => Ok(Exchange::DHCurve25519),
-            _ => Err(Error::new(ErrorKind::InvalidData, "Invalid exchange code")),
-        }
-    }
-}
-
-#[repr(u8)]
-enum Encryption {
-    ChaCha = 0
-}
-
-impl TryFrom<u8> for Encryption {
-    type Error = Error;
-
-    fn try_from(value: u8) -> Result<Self, Self::Error> {
-        match value {
-            0 => Ok(Encryption::ChaCha),
-            _ => Err(Error::new(ErrorKind::InvalidData, "Invalid encryption code")),
-        }
-    }
-}
-
- */
-
 #[derive(Debug)]
 pub struct EncryptedStream {
     socket: TcpStream,
     block: Block,
 }
 
+const KEY_DERIVATION_CONTEXT: &str = concat!(env!("CARGO_PKG_NAME"), "/", env!("CARGO_PKG_VERSION"));
+
 impl EncryptedStream {
+    /// connect and negotiate an encrypted stream as a client
     pub fn connect(address: &str) -> Result<EncryptedStream, Error> {
-        let secret = EphemeralSecret::random();
+        let secret = Secret::random();
-        let public = PublicKey::from(&secret);
+        let public = Public::from(&secret);
 
         let mut socket = TcpStream::connect(address)?;
 
-        socket.write(public.as_bytes())?;
+        socket.write(&public.as_bytes())?;
 
         let mut their_public_bytes = [0u8; 32];
         socket.read_exact(&mut their_public_bytes)?;
 
-        let their_public = PublicKey::from(their_public_bytes);
+        let their_public = Public::from(their_public_bytes);
 
         let shared_secret = secret.diffie_hellman(&their_public);
 
         let mut nonce_bytes = [0u8; 12];
         socket.read_exact(&mut nonce_bytes)?;
 
+        let key = blake3::derive_key(KEY_DERIVATION_CONTEXT, &shared_secret.to_bytes());
+
+        Ok(EncryptedStream::wrap(socket, key, nonce_bytes))
+    }
+
+    pub fn wrap(socket: TcpStream, key: [u8; 32], nonce: [u8; 12]) -> EncryptedStream {
         let mut nonce_u32s = [0u32; 3];
-        u8_to_u32(&mut nonce_u32s, &nonce_bytes);
+        u8_to_u32(&mut nonce_u32s, &nonce);
 
         let mut key_u32s = [0u32; 8];
-        u8_to_u32(&mut key_u32s, &shared_secret.to_bytes());
+        u8_to_u32(&mut key_u32s, &key);
 
-        Ok(EncryptedStream {
+        EncryptedStream {
             socket,
-            block: Block::new(key_u32s, 0, nonce_u32s, 20)
+            block: Block::new(key_u32s, 0, nonce_u32s, 20),
-        })
+        }
     }
 
     pub fn shutdown(&self, how: Shutdown) -> Result<(), Error> {
         self.socket.shutdown(how)
     }
+
+    pub fn reset(&mut self, next_nonce: [u32; 3]) {
+        self.block.reset(next_nonce)
+    }
 }
 
 impl TryFrom<TcpStream> for EncryptedStream {
     type Error = Error;
 
+    /// Accept and negotiate an encrypted connection as a server
     fn try_from(mut socket: TcpStream) -> Result<Self, Self::Error> {
-        let secret = EphemeralSecret::random();
+        let secret = Secret::random();
-        let public = PublicKey::from(&secret);
+        let public = Public::from(&secret);
 
         let mut their_public_bytes = [0u8; 32];
         socket.read(&mut their_public_bytes)?;
 
-        socket.write(public.as_bytes())?;
+        socket.write(&public.as_bytes())?;
 
-        let their_public = PublicKey::from(their_public_bytes);
+        let their_public = Public::from(their_public_bytes);
 
         let shared_secret = secret.diffie_hellman(&their_public);
 
@@ -109,16 +88,9 @@ impl TryFrom<TcpStream> for EncryptedStream {
 
         socket.write(&nonce_bytes)?;
 
-        let mut nonce_u32s = [0u32; 3];
+        let key = blake3::derive_key(KEY_DERIVATION_CONTEXT, &shared_secret.to_bytes());
-        u8_to_u32(&mut nonce_u32s, &nonce_bytes);
 
-        let mut key_u32s = [0u32; 8];
+        Ok(EncryptedStream::wrap(socket, key, nonce_bytes))
-        u8_to_u32(&mut key_u32s, &shared_secret.to_bytes());
-
-        Ok(EncryptedStream {
-            socket,
-            block: Block::new(key_u32s, 0, nonce_u32s, 20)
-        })
     }
 }
 
@@ -154,6 +126,5 @@ impl Write for EncryptedStream {
     }
 }
 
-
 #[cfg(test)]
 mod tests {}

src/main.rs

@@ -1,7 +1,7 @@
 use hermes::EncryptedStream;
 use std::env::args;
 use std::io::{Read, Write};
-use std::net::{Shutdown, TcpListener, TcpStream};
+use std::net::{Shutdown, TcpListener};
 use std::process::exit;
 
 fn main() {
@@ -21,7 +21,9 @@ fn main() {
                 let mut encrypted = EncryptedStream::try_from(incoming.unwrap()).unwrap();
                 println!("successfully encrypted stream");
 
-                encrypted.write(b"the fitness gram pacer test is a multi-stage aerobic fitness test...").unwrap();
+                encrypted
+                    .write(b"the fitness gram pacer test is a multi-stage aerobic fitness test...")
+                    .unwrap();
                 println!("successfully wrote data");
 
                 encrypted.flush().unwrap();