more

Cargo.lock

@@ -17,16 +17,6 @@ version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f26201604c87b1e01bd3d98f8d5d9a8fcbb815e8cedb41ffccbeb4bf593a35fe"
 
-[[package]]
-name = "aead"
-version = "0.5.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d122413f284cf2d62fb1b7db97e02edb8cda96d769b16e443a4f6195e35662b0"
-dependencies = [
- "crypto-common",
- "generic-array",
-]
-
 [[package]]
 name = "aho-corasick"
 version = "1.1.3"
@@ -113,19 +103,6 @@ dependencies = [
  "cpufeatures",
 ]
 
-[[package]]
-name = "chacha20poly1305"
-version = "0.10.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "10cd79432192d1c0f4e1a0fef9527696cc039165d729fb41b3f4f4f354c2dc35"
-dependencies = [
- "aead",
- "chacha20",
- "cipher",
- "poly1305",
- "zeroize",
-]
-
 [[package]]
 name = "cipher"
 version = "0.4.4"
@@ -134,7 +111,6 @@ checksum = "773f3b9af64447d2ce9850330c473515014aa235e6a783b02db81ff39e4a3dad"
 dependencies = [
  "crypto-common",
  "inout",
- "zeroize",
 ]
 
 [[package]]
@@ -159,7 +135,6 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1bfb12502f3fc46cca1bb51ac28df9d618d813cdc3d2f25b9fe775a34af26bb3"
 dependencies = [
  "generic-array",
- "rand_core",
  "typenum",
 ]
 
@@ -692,10 +667,10 @@ name = "ssh-transport"
 version = "0.1.0"
 dependencies = [
  "chacha20",
- "chacha20poly1305",
  "ed25519-dalek",
  "eyre",
  "hex-literal",
+ "poly1305",
  "rand",
  "rand_core",
  "sha2",

ssh-transport/Cargo.toml

@@ -5,9 +5,9 @@ edition = "2021"
 
 [dependencies]
 chacha20 = "0.9.1"
-chacha20poly1305 = "0.10.1"
 ed25519-dalek = { version = "2.1.1" }
 eyre = "0.6.12"
+poly1305 = "0.8.0"
 rand = "0.8.5"
 rand_core = "0.6.4"
 sha2 = "0.10.8"

ssh-transport/src/keys.rs

@@ -1,4 +1,4 @@
-use chacha20poly1305::{ChaCha20Poly1305, KeyInit};
+use chacha20::cipher::{KeyInit, KeyIvInit, StreamCipher, StreamCipherSeek};
 use sha2::Digest;
 
 use crate::Result;
@@ -55,7 +55,8 @@ impl Decryptor for Session {
     }
 
     fn decrypt_packet(&mut self, bytes: &mut [u8], packet_number: u64) {
-        self.encryption_key_client_to_server.decrypt_packet(bytes, packet_number);
+        self.encryption_key_client_to_server
+            .decrypt_packet(bytes, packet_number);
     }
 
     fn rekey(&mut self, h: [u8; 32], k: [u8; 32]) -> Result<(), ()> {
@@ -110,28 +111,39 @@ pub(crate) fn encode_mpint_for_hash(mut key: &[u8], mut add_to_hash: impl FnMut(
 type SshChaCha20 = chacha20::ChaCha20Legacy;
 
 struct SshChaCha20Poly1305 {
-    header_key: [u8; 32],
+    header_key: chacha20::Key,
-    main: ChaCha20Poly1305,
+    main_key: chacha20::Key,
 }
 
 impl SshChaCha20Poly1305 {
     fn new(key: [u8; 64]) -> Self {
         Self {
-            main: ChaCha20Poly1305::new(&<[u8; 32]>::try_from(&key[..32]).unwrap().into()),
+            main_key: <[u8; 32]>::try_from(&key[..32]).unwrap().into(),
-            header_key: key[32..].try_into().unwrap(),
+            header_key: <[u8; 32]>::try_from(&key[32..]).unwrap().into(),
         }
     }
 
     fn decrypt_len(&self, bytes: &mut [u8], packet_number: u64) {
-        use chacha20::cipher::{KeyIvInit, StreamCipher};
-
         // <https://github.com/openssh/openssh-portable/blob/1ec0a64c5dc57b8a2053a93b5ef0d02ff8598e5c/PROTOCOL.chacha20poly1305>
-        let mut cipher =
+        let mut cipher = SshChaCha20::new(&self.header_key, &packet_number.to_be_bytes().into());
-            SshChaCha20::new(&self.header_key.into(), &packet_number.to_be_bytes().into());
         cipher.apply_keystream(bytes);
     }
 
     fn decrypt_packet(&mut self, bytes: &mut [u8], packet_number: u64) {
+        // <https://github.com/openssh/openssh-portable/blob/1ec0a64c5dc57b8a2053a93b5ef0d02ff8598e5c/PROTOCOL.chacha20poly1305>
+        let mut cipher = SshChaCha20::new(&self.main_key, &packet_number.to_be_bytes().into());
+
+        let mut poly1305_key = [0; poly1305::KEY_SIZE];
+        cipher.apply_keystream(&mut poly1305_key);
+
+        let total_len = bytes.len();
+        let payload = &mut bytes[..(total_len - 16)];
+
+        // TODO: Compute it over THE LENGTH AS WELL
+        let hash = poly1305::Poly1305::new(&poly1305_key.into()).compute_unpadded(payload);
+
+        cipher.seek(1_u32);
+
         todo!()
     }
 }