fix: outgoing messages should not be decrypted

Author: kaichaosun

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) ))
 
 

src/chat_sdk/errors.nim

@@ -8,6 +8,7 @@ type
   ErrorCode* = enum
     errTypeError
     errWrapped
+    errDecryptOutgoing
 
 
 proc `$`*(x: ChatError): string =

src/naxolotl/naxolotl.nim

@@ -16,7 +16,7 @@ const maxSkip = 10
 
 
 type Doubleratchet* = object
-  dhSelf: PrivateKey
+  dhSelf*: PrivateKey
   dhRemote: PublicKey
 
   rootKey: RootKey