HyperDbg Documentation
CommunityDownloadResearchTutorialhwdbg
  • HyperDbg
  • Getting Started
    • Quick Start
    • FAQ
    • Build & Install
    • Attach to HyperDbg
      • Attach to a remote machine
      • Attach to local machine
      • Start a new process
      • Attach to a running process
  • Using HyperDbg
    • Prerequisites
      • Operation Modes
      • How to create a condition?
      • How to create an action?
      • Signatures
    • User-mode Debugging
      • Principles
      • Examples
        • basics
        • events
          • Getting Results of a System-call
    • Kernel-mode Debugging
      • Principles
      • Examples
        • beginning
          • Connecting To HyperDbg
          • Configuring Symbol Server/Path
        • basics
          • Setting Breakpoints & Stepping Instructions
          • Displaying & Editing & Searching Memory
          • Showing & Modifying Registers and Flags
          • Switching to a Specific Process or Thread
          • Mapping Data & Create Structures, and Enums From Symbols
        • events
          • Managing Events
          • Hooking Any Function
          • Intercepting All SYSCALLs
          • Monitoring Accesses To Structures
          • Triggering Special Instructions
          • Identifying System Behavior
        • Scripting Language Examples
    • Software Development Kit (SDK)
      • Events
        • Conditions
        • Actions
      • IOCTL
        • Event Registration
  • Commands
    • Debugging Commands
      • ? (evaluate and execute expressions and scripts in debuggee)
      • ~ (display and change the current operating core)
      • a (assemble virtual address)
      • load (load the kernel modules)
      • unload (unload the kernel modules)
      • status (show the debuggee status)
      • events (show and modify active/disabled events)
      • p (step-over)
      • t (step-in)
      • i (instrumentation step-in)
      • gu (step-out or go up)
      • r (read or modify registers)
      • bp (set breakpoint)
      • bl (list breakpoints)
      • be (enable breakpoints)
      • bd (disable breakpoints)
      • bc (clear and remove breakpoints)
      • g (continue debuggee or processing kernel packets)
      • x (examine symbols and find functions and variables address)
      • db, dc, dd, dq (read virtual memory)
      • eb, ed, eq (edit virtual memory)
      • sb, sd, sq (search virtual memory)
      • u, u64, u2, u32 (disassemble virtual address)
      • k, kd, kq (display stack backtrace)
      • dt (display and map virtual memory to structures)
      • struct (make structures, enums, data types from symbols)
      • sleep (wait for specific time in the .script command)
      • pause (break to the debugger and pause processing kernel packets)
      • print (evaluate and print expression in debuggee)
      • lm (view loaded modules)
      • cpu (check cpu supported technologies)
      • rdmsr (read model-specific register)
      • wrmsr (write model-specific register)
      • flush (remove pending kernel buffers and messages)
      • prealloc (reserve pre-allocated pools)
      • preactivate (pre-activate special functionalities)
      • output (create output source for event forwarding)
      • test (test functionalities)
      • settings (configures different options and preferences)
      • exit (exit from the debugger)
    • Meta Commands
      • .help (show the help of commands)
      • .debug (prepare and connect to debugger)
      • .connect (connect to a session)
      • .disconnect (disconnect from a session)
      • .listen (listen on a port and wait for the debugger to connect)
      • .status (show the debugger status)
      • .start (start a new process)
      • .restart (restart the process)
      • .attach (attach to a process)
      • .detach (detach from the process)
      • .switch (show the list and switch between active debugging processes)
      • .kill (terminate the process)
      • .process, .process2 (show the current process and switch to another process)
      • .thread, .thread2 (show the current thread and switch to another thread)
      • .pagein (bring the page into the RAM)
      • .dump (save the virtual memory into a file)
      • .formats (show number formats)
      • .script (run batch script commands)
      • .sympath (set the symbol server)
      • .sym (load pdb symbols)
      • .pe (parse PE file)
      • .logopen (open log file)
      • .logclose (close log file)
      • .cls (clear the screen)
    • Extension Commands
      • !a (assemble physical address)
      • !pte (display page-level address and entries)
      • !db, !dc, !dd, !dq (read physical memory)
      • !eb, !ed, !eq (edit physical memory)
      • !sb, !sd, !sq (search physical memory)
      • !u, !u64, !u2, !u32 (disassemble physical address)
      • !dt (display and map physical memory to structures)
      • !track (track and map function calls and returns to the symbols)
      • !epthook (hidden hook with EPT - stealth breakpoints)
      • !epthook2 (hidden hook with EPT - detours)
      • !monitor (monitor read/write/execute to a range of memory)
      • !syscall, !syscall2 (hook system-calls)
      • !sysret, !sysret2 (hook SYSRET instruction execution)
      • !mode (detect kernel-to-user and user-to-kernel transitions)
      • !cpuid (hook CPUID instruction execution)
      • !msrread (hook RDMSR instruction execution)
      • !msrwrite (hook WRMSR instruction execution)
      • !tsc (hook RDTSC/RDTSCP instruction execution)
      • !pmc (hook RDPMC instruction execution)
      • !vmcall (hook hypercalls)
      • !exception (hook first 32 entries of IDT)
      • !interrupt (hook external device interrupts)
      • !dr (hook access to debug registers)
      • !ioin (hook IN instruction execution)
      • !ioout (hook OUT instruction execution)
      • !hide (enable transparent-mode)
      • !unhide (disable transparent-mode)
      • !measure (measuring and providing details for transparent-mode)
      • !va2pa (convert a virtual address to physical address)
      • !pa2va (convert physical address to virtual address)
      • !dump (save the physical memory into a file)
      • !pcitree (show PCI/PCIe device tree)
      • !pcicam (dump the PCI/PCIe configuration space)
      • !idt (show Interrupt Descriptor Table entries)
      • !apic (dump local APIC entries in XAPIC and X2APIC modes)
      • !ioapic (dump I/O APIC)
    • Scripting Language
      • Assumptions & Evaluations
      • Variables & Assignments
      • Casting & Type-awareness
      • Conditionals & Loops
      • Constants & Functions
      • Debugger Script (DS)
      • Examples
        • view system state (registers, memory, variables)
        • change system state (registers, memory, variables)
        • trace function calls
        • pause the debugger conditionally
        • conditional breakpoints and events
        • patch the normal sequence of execution
        • access to a shared variable from different cores
        • count occurrences of events
      • Functions
        • debugger
          • pause
        • events
          • event_enable
          • event_disable
          • event_clear
          • event_sc
          • event_inject
          • event_inject_error_code
          • flush
        • exports
          • print
          • printf
        • interlocked
          • interlocked_compare_exchange
          • interlocked_decrement
          • interlocked_exchange
          • interlocked_exchange_add
          • interlocked_increment
        • memory
          • check_address
          • eb, ed, eq
          • eb_pa, ed_pa, eq_pa
          • memcpy
          • memcpy_pa
          • memcmp
          • virtual_to_physical
          • physical_to_virtual
        • diassembler
          • disassemble_len
          • disassemble_len32
        • spinlocks
          • spinlock_lock
          • spinlock_lock_custom_wait
          • spinlock_unlock
        • strings
          • strlen
          • wcslen
          • strcmp
          • strncmp
          • wcscmp
          • wcsncmp
    • Commands Map
  • Tips & Tricks
    • Considerations
      • Basic concepts in Intel VT-x
      • VMX root-mode vs VMX non-root mode
      • The "unsafe" behavior
      • Script engine in VMX non-root mode
      • Difference between process and thread switching commands
      • Accessing Invalid Address
      • Transparent Mode
    • Nested-Virtualization Environments
      • Supported Virtual Machines
      • Run HyperDbg on VMware
      • Run HyperDbg on Hyper-V
      • Supporting VMware/Hyper-V
      • VMware backdoor I/O ports
    • Misc
      • Event forwarding
      • Event short-circuiting
      • Event calling stage
      • Instant events
      • Message overflow
      • Customize build
        • Increase Communication Buffer Size
        • Number of EPT Hooks in One Page
        • Change Script Engine Limitations
      • Enable and disable events in Debugger Mode
      • Switch to New Process Layout
  • Contribution
    • Style Guide
      • Coding style
      • Command style
      • Doxygen style
    • Logo & Artworks
  • Design
    • Features
      • VMM (Module)
        • Control over NMIs
        • VMX root-mode compatible message tracing
        • Design of !epthook
        • Design of !epthook2
        • Design of !monitor
        • Design of !syscall & !sysret
        • Design of !exception & !interrupt
    • Debugger Internals
      • Events
      • Conditions
      • Actions
      • Kernel Debugger
        • Design Perspective
        • Connection
  • Links
    • Twitter
    • Telegram
    • Discord
    • Matrix
    • Mastodon
    • YouTube
    • hwdbg (Chip Debugger)
    • Doxygen
    • Contribution
Powered by GitBook
On this page
  • Command
  • Syntax
  • Description
  • Parameters
  • Examples
  • IOCTL
  • Remarks
  • Requirements
  • Related
Edit on GitHub
  1. Commands
  2. Debugging Commands

output (create output source for event forwarding)

Description of the 'output' command in HyperDbg.

Previouspreactivate (pre-activate special functionalities)Nexttest (test functionalities)

Last updated 9 months ago

Command

output

Syntax

output

output [create Name (string)] [file|namedpipe|tcp|module Address (string)]

output [open|close Name (string)]

Description

Create, open, or close a source output for event forwarding.

You can read more about event forwarding .

Examples of using this mechanism in different programming languages are available here:

Parameters

[create Name (string)]

The name of the instance output to be created.

[file|namedpipe|tcp|module Address (string)]

Type and address of the target resource.

[open|close Name (string)]

The action of this command or whether this command tries to open an output source or close it combined with its name.

If you don't specify any parameters to the 'output' command, it shows a list of output sources and their status.

Examples

The following command creates an output source, which is a file and the results of the command (script) will be saved into the c:\users\sina\desktop\output.txt.

HyperDbg> output create MyOutputName1 file c:\users\sina\desktop\output.txt

The following command creates an output source, which is a tcp and the results of the command (script) will be sent into the 192.168.1.10:8080.

HyperDbg> output create MyOutputName2 tcp 192.168.1.10:8080

The following command creates an output source, which is a namedpipe and the results of the command (script) will be sent into the \\.\Pipe\HyperDbgOutput.

HyperDbg> output create MyOutputName3 namedpipe \\.\Pipe\HyperDbgOutput

You cannot use the above resources until you open them using the following command. This command opens an output source (named "MyOutputName1") that was previously created by the output's create parameter.

HyperDbg> output open MyOutputName1

When you finished using an output source, you can close it using the following command. Once you close an output source, you cannot use it anymore, and also, you CANNOT open it again, but once again, you can create a new source with the same address but with a different name.

HyperDbg> output close MyOutputName1
HyperDbg> !syscall script { print(@rax); } output {MyOutputName1}

It is also possible to send the results to several output sources. You should separate the output names with , .

For example :

HyperDbg> !syscall script { print(@rax); } output {MyOutputName1 , MyOutputName2 , MyOutputName3}

Generally, DLLs (in all low-level languages) should export a function with the name hyperdbg_event_forwarding with the first parameter as a pointer to the buffer message and the second parameter as an integer with the size that will be called by HyperDbg's event forwarding module once an event is triggered. The following example is the definition of the function in C/C++ (You can do the same in Rust, GO, etc.).

hyperdbg_event_forwarding(const char* buffer_message, unsigned int buffer_length);

After compiling the above function and exporting the above function (e.g., by using __declspec(dllexport)), you can open a module using the following command:

output create MyOutputName1 module C:\module\event_forwarding_module.dll

and after that, open it using the following command:

output open MyOutputName1

and then (same as above examples) you can pass the events using the following event:

!epthook nt!ExAllocatePoolWithTag script {
	printf("Pool allocation called!");
} output { MyOutputName1 }

In case, you want to see a list of sources, you can use the 'output' command without any parameter.

HyperDbg> output
1  file        not opened       MyOutputName1
2  file        opened           MyOutputName2
3  file        not opened       MyOutputName3

IOCTL

None

Remarks

You cannot use event forwarding in the immediate messaging mode in events (imm no).

Requirements

None

Related

After creating and opening the output source, you can use its name in all HyperDbg events. You should pass output {MyOutputName1} when you are creating an event, for example is an event so that you can use it like this :

You can specify up to 5 output sources in the default build of HyperDbg, but if you need more output sources for a single event, then you should compile HyperDbg with different configurations as described on and change the DebuggerOutputSourceMaximumRemoteSourceForSingleEvent.

Starting from v0.10, HyperDbg supports modules (DLLs) as functions directly load DLLs and have the ability to forward events to functions. Note that, DLLs should be compiled into 64-bit binaries (32-bit binaries are not supported). Examples of DLLs are available in and .

You can use this command to forward the scripts' results from all the .

!syscall
Customize Build
Rust
C++
events
Event Forwarding
here
LogoGitHub - HyperDbg/event-forwarding-examples: Examples of using "Event Forwarding" mechanism in HyperDbgGitHub