From 523dca43e18b902a4efb2e8bbc796ae32668cf26 Mon Sep 17 00:00:00 2001
From: kaichaosun <kaichaosuna@gmail.com>
Date: Fri, 28 Nov 2025 16:09:02 +0800
Subject: [PATCH] fix: outgoing messages should not be decrypted

---
 src/chat_sdk/conversations/private_v1.nim | 4 ++++
 src/chat_sdk/errors.nim                   | 1 +
 src/naxolotl/naxolotl.nim                 | 2 +-
 3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/chat_sdk/conversations/private_v1.nim b/src/chat_sdk/conversations/private_v1.nim
index 7554bc9..08c6deb 100644
--- a/src/chat_sdk/conversations/private_v1.nim
+++ b/src/chat_sdk/conversations/private_v1.nim
@@ -94,6 +94,10 @@ proc decrypt*(convo: PrivateV1, enc: EncryptedPayload): Result[seq[byte], ChatEr
   )
   copyMem(addr header.dhPublic[0], unsafeAddr dr.dh[0], dr.dh.len) # TODO: Avoid this copy
 
+  if convo.doubleratchet.dhSelf.public == header.dhPublic:
+    info "outgoing message, no need to decrypt"
+    return err(ChatError(code: errDecryptOutgoing, context: "Attempted to decrypt outgoing message"))
+
   convo.doubleratchet.decrypt(header, dr.ciphertext, @[]).mapErr(proc(e: NaxolotlError): ChatError = ChatError(code: errWrapped, context: repr(e) ))
 
 
diff --git a/src/chat_sdk/errors.nim b/src/chat_sdk/errors.nim
index e7b8008..a838439 100644
--- a/src/chat_sdk/errors.nim
+++ b/src/chat_sdk/errors.nim
@@ -8,6 +8,7 @@ type
   ErrorCode* = enum
     errTypeError
     errWrapped
+    errDecryptOutgoing
 
 
 proc `$`*(x: ChatError): string =
diff --git a/src/naxolotl/naxolotl.nim b/src/naxolotl/naxolotl.nim
index f2b0fb8..0458126 100644
--- a/src/naxolotl/naxolotl.nim
+++ b/src/naxolotl/naxolotl.nim
@@ -16,7 +16,7 @@ const maxSkip = 10
 
 
 type Doubleratchet* = object
-  dhSelf: PrivateKey
+  dhSelf*: PrivateKey
   dhRemote: PublicKey
 
   rootKey: RootKey