diff --git a/.vscode/extensions.json b/.vscode/extensions.json
new file mode 100644
index 0000000..50f33e0
--- /dev/null
+++ b/.vscode/extensions.json
@@ -0,0 +1,6 @@
+{
+ "recommendations": [
+ "golang.go",
+ "ms-vscode.cpptools"
+ ]
+}
diff --git a/.vscode/tasks.json b/.vscode/tasks.json
new file mode 100644
index 0000000..7b77ddc
--- /dev/null
+++ b/.vscode/tasks.json
@@ -0,0 +1,23 @@
+{
+ // See https://go.microsoft.com/fwlink/?LinkId=733558
+ // for the documentation about the tasks.json format
+ "version": "2.0.0",
+ "tasks": [
+ {
+ "label": "Build shelidate.exe",
+ "type": "shell",
+ "command": "gcc shellcode/main.c -o shelidate.exe --entry=entry -nostdlib -ffunction-sections -fno-asynchronous-unwind-tables -fno-ident '-Wl,--strip-all,--no-seh,-Tshellcode/main.S'",
+ "problemMatcher": [
+ "$gcc"
+ ]
+ },
+ {
+ "label": "Build shelidate.bin",
+ "type": "shell",
+ "command": "objcopy -O binary --only-section=.text shelidate.exe shelidate.bin",
+ "problemMatcher": [
+ "$gcc"
+ ]
+ }
+ ]
+}
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
new file mode 100644
index 0000000..b16bd94
--- /dev/null
+++ b/CONTRIBUTING.md
@@ -0,0 +1,33 @@
+# How to contribute
+
+We'd love to accept your patches and contributions to this project.
+
+## Before you begin
+
+### Sign our Contributor License Agreement
+
+Contributions to this project must be accompanied by a
+[Contributor License Agreement](https://cla.developers.google.com/about) (CLA).
+You (or your employer) retain the copyright to your contribution; this simply
+gives us permission to use and redistribute your contributions as part of the
+project.
+
+If you or your current employer have already signed the Google CLA (even if it
+was for a different project), you probably don't need to do it again.
+
+Visit to see your current agreements or to
+sign a new one.
+
+### Review our community guidelines
+
+This project follows
+[Google's Open Source Community Guidelines](https://opensource.google/conduct/).
+
+## Contribution process
+
+### Code reviews
+
+All submissions, including submissions by project members, require review. We
+use GitHub pull requests for this purpose. Consult
+[GitHub Help](https://help.github.com/articles/about-pull-requests/) for more
+information on using pull requests.
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..261eeb9
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,201 @@
+ Apache License
+ Version 2.0, January 2004
+ http://www.apache.org/licenses/
+
+ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+ 1. Definitions.
+
+ "License" shall mean the terms and conditions for use, reproduction,
+ and distribution as defined by Sections 1 through 9 of this document.
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+ "Licensor" shall mean the copyright owner or entity authorized by
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+ "Legal Entity" shall mean the union of the acting entity and all
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+ otherwise, or (ii) ownership of fifty percent (50%) or more of the
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+
+ "You" (or "Your") shall mean an individual or Legal Entity
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+ "Object" form shall mean any form resulting from mechanical
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+ not limited to compiled object code, generated documentation,
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+ "Work" shall mean the work of authorship, whether in Source or
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+ "Derivative Works" shall mean any work, whether in Source or Object
+ form, that is based on (or derived from) the Work and for which the
+ editorial revisions, annotations, elaborations, or other modifications
+ represent, as a whole, an original work of authorship. For the purposes
+ of this License, Derivative Works shall not include works that remain
+ separable from, or merely link (or bind by name) to the interfaces of,
+ the Work and Derivative Works thereof.
+
+ "Contribution" shall mean any work of authorship, including
+ the original version of the Work and any modifications or additions
+ to that Work or Derivative Works thereof, that is intentionally
+ submitted to Licensor for inclusion in the Work by the copyright owner
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+ communication on electronic mailing lists, source code control systems,
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+ designated in writing by the copyright owner as "Not a Contribution."
+
+ "Contributor" shall mean Licensor and any individual or Legal Entity
+ on behalf of whom a Contribution has been received by Licensor and
+ subsequently incorporated within the Work.
+
+ 2. Grant of Copyright License. Subject to the terms and conditions of
+ this License, each Contributor hereby grants to You a perpetual,
+ worldwide, non-exclusive, no-charge, royalty-free, irrevocable
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+ 3. Grant of Patent License. Subject to the terms and conditions of
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+ meet the following conditions:
+
+ (a) You must give any other recipients of the Work or
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+
+ (b) You must cause any modified files to carry prominent notices
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+
+ (c) You must retain, in the Source form of any Derivative Works
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+ (d) If the Work includes a "NOTICE" text file as part of its
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+ wherever such third-party notices normally appear. The contents
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+ do not modify the License. You may add Your own attribution
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+ or as an addendum to the NOTICE text from the Work, provided
+ that such additional attribution notices cannot be construed
+ as modifying the License.
+
+ You may add Your own copyright statement to Your modifications and
+ may provide additional or different license terms and conditions
+ for use, reproduction, or distribution of Your modifications, or
+ for any such Derivative Works as a whole, provided Your use,
+ reproduction, and distribution of the Work otherwise complies with
+ the conditions stated in this License.
+
+ 5. Submission of Contributions. Unless You explicitly state otherwise,
+ any Contribution intentionally submitted for inclusion in the Work
+ by You to the Licensor shall be under the terms and conditions of
+ this License, without any additional terms or conditions.
+ Notwithstanding the above, nothing herein shall supersede or modify
+ the terms of any separate license agreement you may have executed
+ with Licensor regarding such Contributions.
+
+ 6. Trademarks. This License does not grant permission to use the trade
+ names, trademarks, service marks, or product names of the Licensor,
+ except as required for reasonable and customary use in describing the
+ origin of the Work and reproducing the content of the NOTICE file.
+
+ 7. Disclaimer of Warranty. Unless required by applicable law or
+ agreed to in writing, Licensor provides the Work (and each
+ Contributor provides its Contributions) on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
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+ PARTICULAR PURPOSE. You are solely responsible for determining the
+ appropriateness of using or redistributing the Work and assume any
+ risks associated with Your exercise of permissions under this License.
+
+ 8. Limitation of Liability. In no event and under no legal theory,
+ whether in tort (including negligence), contract, or otherwise,
+ unless required by applicable law (such as deliberate and grossly
+ negligent acts) or agreed to in writing, shall any Contributor be
+ liable to You for damages, including any direct, indirect, special,
+ incidental, or consequential damages of any character arising as a
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+ Work (including but not limited to damages for loss of goodwill,
+ work stoppage, computer failure or malfunction, or any and all
+ other commercial damages or losses), even if such Contributor
+ has been advised of the possibility of such damages.
+
+ 9. Accepting Warranty or Additional Liability. While redistributing
+ the Work or Derivative Works thereof, You may choose to offer,
+ and charge a fee for, acceptance of support, warranty, indemnity,
+ or other liability obligations and/or rights consistent with this
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+ on Your own behalf and on Your sole responsibility, not on behalf
+ of any other Contributor, and only if You agree to indemnify,
+ defend, and hold each Contributor harmless for any liability
+ incurred by, or claims asserted against, such Contributor by reason
+ of your accepting any such warranty or additional liability.
+
+ END OF TERMS AND CONDITIONS
+
+ APPENDIX: How to apply the Apache License to your work.
+
+ To apply the Apache License to your work, attach the following
+ boilerplate notice, with the fields enclosed by brackets "[]"
+ replaced with your own identifying information. (Don't include
+ the brackets!) The text should be enclosed in the appropriate
+ comment syntax for the file format. We also recommend that a
+ file or class name and description of purpose be included on the
+ same "printed page" as the copyright notice for easier
+ identification within third-party archives.
+
+ Copyright [yyyy] [name of copyright owner]
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..34dd22f
--- /dev/null
+++ b/README.md
@@ -0,0 +1,53 @@
+# shelidate
+
+A shellcode integration testing harness. shelidate can be used standalone to confirm payload callbacks without standing up a full command and control framework or integrated into the testing process to ensure payloads execute properly.
+
+## Usage
+
+```
+Usage of shelidate.exe:
+ -address string
+ shellcode listener address (default "127.0.0.1:1337")
+ -command string
+ command to execute while listening, use {{.Shellcode}} to substitute the shellcode file
+ -timeout string
+ timeout duration (only used if commmand is specified) (default "30s")
+```
+
+### Examples
+
+Generate shellcode that calls back to `127.0.0.1:1337` and listen indefinitely:
+
+```
+shelidate.exe
+```
+
+Generate shellcode, run the command `shellcode_runner.exe C:\Path\To\Shellcode`, and time out after 30 seconds
+
+```
+shelidate.exe -command 'shellcode_runner.exe {{.Shellcode}}'
+```
+
+## Setup
+
+shelidate expects Go 1.22 on Windows to build. shelidate can be build with
+
+```
+go build -o shelidate ./cmd/...
+```
+
+### Building shellcode
+
+[MinGW-w64](https://www.mingw-w64.org/) must be installed and `gcc` and `objcopy` must be available on the path to rebuild the shellcode, `shelidate.bin`.
+
+The initial executable can be built with:
+
+```
+gcc shellcode/main.c -o shelidate.exe --entry=entry -nostdlib -ffunction-sections -fno-asynchronous-unwind-tables -fno-ident '-Wl,--strip-all,--no-seh,-Tshellcode/main.S'
+```
+
+The shellcode can be extracted with:
+
+```
+objcopy -O binary --only-section=.text shelidate.exe shelidate.bin
+```
diff --git a/cmd/main.go b/cmd/main.go
new file mode 100644
index 0000000..84afc6a
--- /dev/null
+++ b/cmd/main.go
@@ -0,0 +1,134 @@
+// Copyright 2024 Google LLC
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+// https://www.apache.org/licenses/LICENSE-2.0
+
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package main
+
+import (
+ "bytes"
+ "context"
+ "flag"
+ "html/template"
+ "log"
+ "math/rand"
+ "os"
+ "os/exec"
+ "os/signal"
+ "sync"
+ "syscall"
+ "time"
+
+ "github.com/mandiant/shelidate"
+)
+
+var address = flag.String("address", "127.0.0.1:1337", "shellcode listener address")
+var command = flag.String("command", "", "command to execute while listening, use {{.Shellcode}} to substitute the shellcode file")
+var timeout = flag.String("timeout", "30s", "timeout duration (only used if commmand is specified)")
+
+type Variables struct {
+ Shellcode string
+}
+
+func main() {
+ flag.Parse()
+
+ var svr shelidate.Server
+
+ c := make(chan os.Signal, 1)
+ signal.Notify(c, os.Interrupt, syscall.SIGTERM)
+ wg := new(sync.WaitGroup)
+
+ if err := svr.Listen(*address); err != nil {
+ log.Fatalf("failed to start listener - address: %v - error: %v", *address, err)
+ }
+
+ log.Printf("callback server listening - address: %v", *address)
+
+ dir, err := os.Getwd()
+ if err != nil {
+ log.Fatalf("failed to get working directory - error: %v", err)
+ }
+
+ shellcode, err := svr.Generate(dir, rand.Uint32())
+ if err != nil {
+ log.Fatalf("failed to generate shellcode - error: %v", err)
+ }
+ defer os.Remove(shellcode.Path)
+
+ log.Printf("generated test shellcode: %v", shellcode.Path)
+
+ var cmd string
+ if *command != "" {
+ tmpl, err := template.New("command").Parse(*command)
+ if err != nil {
+ log.Fatalf("failed to template provided command - command: %v - error: %v", command, err)
+ }
+
+ var buf bytes.Buffer
+ if err := tmpl.Execute(
+ &buf,
+ Variables{
+ Shellcode: shellcode.Path,
+ },
+ ); err != nil {
+ log.Fatalf("failed to template provided command - command: %v - error: %v", command, err)
+ }
+
+ cmd = buf.String()
+ }
+
+ wg.Add(1)
+
+ var ctx context.Context
+ var cancel context.CancelFunc
+
+ if cmd != "" {
+ duration, err := time.ParseDuration(*timeout)
+ if err != nil {
+ log.Fatalf("failed to parse provided timeout - timout: %v - error: %v", *timeout, err)
+ }
+ ctx, cancel = context.WithTimeout(context.Background(), duration)
+ } else {
+ ctx, cancel = context.WithCancel(context.Background())
+ }
+
+ go func() {
+ defer wg.Done()
+ defer svr.Close()
+ defer shellcode.Cancel()
+ defer cancel()
+
+ for {
+ select {
+ case <-c:
+ return
+ case <-ctx.Done():
+ return
+ case <-shellcode.Recv:
+ log.Printf("test shellcode checked in")
+ if cmd != "" {
+ time.Sleep(500 * time.Millisecond)
+ return
+ }
+ }
+ }
+ }()
+
+ if cmd != "" {
+ log.Printf("running the command: %v", cmd)
+ if err := exec.CommandContext(ctx, "C:\\Windows\\System32\\cmd.exe", "/c", cmd).Run(); err != nil {
+ log.Fatalf("command failed to run: %v", err)
+ }
+ }
+
+ wg.Wait()
+}
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..d998541
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module github.com/mandiant/shelidate
+
+go 1.22.5
diff --git a/shelidate.bin b/shelidate.bin
new file mode 100644
index 0000000..1b2cde0
Binary files /dev/null and b/shelidate.bin differ
diff --git a/shelidate.go b/shelidate.go
new file mode 100644
index 0000000..1751967
--- /dev/null
+++ b/shelidate.go
@@ -0,0 +1,191 @@
+// Copyright 2024 Google LLC
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+// https://www.apache.org/licenses/LICENSE-2.0
+
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package shelidate
+
+import (
+ "bytes"
+ _ "embed"
+ "encoding/binary"
+ "fmt"
+ "io"
+ "math/big"
+ "net"
+ "os"
+ "path/filepath"
+ "strconv"
+ "sync"
+)
+
+//go:embed shelidate.bin
+var shelidate []byte
+
+func inetaton(host string) uint32 {
+ res := big.NewInt(0)
+ res.SetBytes(net.ParseIP(host).To4())
+ return uint32(res.Uint64())
+}
+
+type val struct{}
+
+type Server struct {
+ address string
+ l net.Listener
+ mu sync.Mutex
+ ch map[uint32]chan<- val
+}
+
+type Shellcode struct {
+ Path string
+ Recv <-chan val
+ Cancel Cancel
+}
+
+type Cancel func()
+
+func (s *Server) Listen(address string) error {
+ var err error
+ s.l, err = net.Listen("tcp", address)
+ if err != nil {
+ return err
+ }
+ s.address = address
+ go func() {
+ for {
+ conn, err := s.l.Accept()
+ if err != nil {
+ return
+ }
+
+ go s.handle(conn)
+ }
+ }()
+ return nil
+}
+
+func (s *Server) Close() error {
+ return s.l.Close()
+}
+
+func (s *Server) handle(conn net.Conn) error {
+ defer conn.Close()
+ var value uint32
+ if err := binary.Read(conn, binary.LittleEndian, &value); err != nil {
+ return err
+ }
+
+ s.mu.Lock()
+ if s.ch != nil {
+ ch, ok := s.ch[value]
+ s.mu.Unlock()
+ if ok {
+ ch <- val{}
+ }
+ } else {
+ s.mu.Unlock()
+ }
+
+ return nil
+}
+
+func (s *Server) Generate(dir string, value uint32) (Shellcode, error) {
+ if s.address == "" {
+ return Shellcode{}, fmt.Errorf("must be listening before generating shellcode")
+ }
+
+ s.mu.Lock()
+ defer s.mu.Unlock()
+
+ if s.ch == nil {
+ s.ch = make(map[uint32]chan<- val)
+ }
+
+ _, ok := s.ch[value]
+ if ok {
+ return Shellcode{}, fmt.Errorf("value already in use")
+ }
+
+ host, port, err := net.SplitHostPort(s.address)
+ if err != nil {
+ return Shellcode{}, fmt.Errorf("failed to parse listen address: %v", err)
+ }
+
+ uPort, err := strconv.ParseUint(port, 10, 32)
+ if err != nil {
+ return Shellcode{}, fmt.Errorf("failed to parse listen address: %v", err)
+ }
+
+ uHost := inetaton(host)
+
+ var b bytes.Buffer
+ if _, err := b.Write([]byte{0xEB, 0x13, 0x58, 0xB9}); err != nil {
+ return Shellcode{}, fmt.Errorf("failed to prep shellcode: %v", err)
+ }
+
+ if err := binary.Write(&b, binary.BigEndian, uint16(uPort)); err != nil {
+ return Shellcode{}, fmt.Errorf("failed to prep shellcode: %v", err)
+ }
+
+ if _, err := b.Write([]byte{0x00, 0x00}); err != nil {
+ return Shellcode{}, fmt.Errorf("failed to prep shellcode: %v", err)
+ }
+
+ if err := b.WriteByte(0xBA); err != nil {
+ return Shellcode{}, fmt.Errorf("failed to prep shellcode: %v", err)
+ }
+
+ if err := binary.Write(&b, binary.BigEndian, uHost); err != nil {
+ return Shellcode{}, fmt.Errorf("failed to prep shellcode: %v", err)
+ }
+
+ if _, err := b.Write([]byte{0x41, 0xB8}); err != nil {
+ return Shellcode{}, fmt.Errorf("failed to prep shellcode: %v", err)
+ }
+
+ if err := binary.Write(&b, binary.LittleEndian, value); err != nil {
+ return Shellcode{}, fmt.Errorf("failed to prep shellcode: %v", err)
+ }
+
+ if _, err := b.Write([]byte{0xFF, 0xE0, 0xE8, 0xE8, 0xFF, 0xFF, 0xFF}); err != nil {
+ return Shellcode{}, fmt.Errorf("failed to prep shellcode: %v", err)
+ }
+
+ out := filepath.Join(dir, fmt.Sprintf("shellcode_%d.bin", value))
+
+ fd, err := os.Create(out)
+ if err != nil {
+ return Shellcode{}, fmt.Errorf("failed to create shellcode file: %v", err)
+ }
+ defer fd.Close()
+
+ if _, err := io.Copy(fd, &b); err != nil {
+ return Shellcode{}, fmt.Errorf("failed to write shellcode file: %v", err)
+ }
+
+ if _, err := fd.Write(shelidate); err != nil {
+ return Shellcode{}, fmt.Errorf("failed to write shellcode file: %v", err)
+ }
+
+ ch := make(chan val)
+ s.ch[value] = ch
+
+ return Shellcode{
+ Path: out,
+ Recv: ch,
+ Cancel: func() {
+ s.mu.Lock()
+ defer s.mu.Unlock()
+ delete(s.ch, value)
+ },
+ }, nil
+}
diff --git a/shellcode/main.S b/shellcode/main.S
new file mode 100644
index 0000000..4e6ace2
--- /dev/null
+++ b/shellcode/main.S
@@ -0,0 +1,21 @@
+/* Copyright 2024 Google LLC
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+ https://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License. */
+SECTIONS
+{
+ .text 0x140001000:
+ {
+ *(.text$entry)
+ *(.text*)
+ }
+}
diff --git a/shellcode/main.c b/shellcode/main.c
new file mode 100644
index 0000000..6f99a14
--- /dev/null
+++ b/shellcode/main.c
@@ -0,0 +1,224 @@
+// Copyright 2024 Google LLC
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+// https://www.apache.org/licenses/LICENSE-2.0
+
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#define WIN32_LEAN_AND_MEAN
+
+#include
+#include
+#include
+
+#pragma comment (lib, "Ws2_32.lib")
+
+// Dependency Loading
+typedef PVOID(WINAPI* FnGetProcAddress)(HMODULE mod, char* apiName);
+typedef HMODULE(WINAPI* FnLoadLibraryA)(char* moduleName);
+typedef HMODULE(WINAPI* FnGetModuleHandleA)(LPCSTR lpModuleName);
+typedef void(WINAPI* FnSleep)(DWORD dwMilliseconds);
+typedef void(WINAPI* FnExitProcess)(UINT uExitCode);
+// sockets
+typedef int(WINAPI* FnWSAStartup)(WORD wVersionRequired, LPWSADATA lpWSAData);
+typedef SOCKET(WSAAPI* FnWSASocketA)(int af, int type, int protocol, LPWSAPROTOCOL_INFOA lpProtocolInfo, GROUP g, DWORD dwFlags);
+typedef int(WSAAPI* FnConnect)(SOCKET s, const SOCKADDR* name, int namelen);
+typedef int(WSAAPI* FnSend)(SOCKET s, const char* buf, int len, int flags);
+typedef int(WSAAPI* FnCloseSocket)(SOCKET s);
+
+DWORD entry(int port, unsigned long host, int nonce);
+PPEB GetPEB();
+PVOID GetKernel32DLL(PPEB ppeb);
+HMODULE MemGetProcAddress(PVOID pModule, PCSTR funcName);
+
+DWORD entry(int port, unsigned long host, int nonce) {
+ PVOID kernel32 = NULL;
+ FnLoadLibraryA myLoadLibrary = NULL;
+ FnGetProcAddress myGetProcAddress = NULL;
+ FnSleep mySleep = NULL;
+ FnExitProcess myExitProcess = NULL;
+
+ FnWSAStartup myWSAStartup = NULL;
+ FnWSASocketA myWSASocketA = NULL;
+ FnConnect myConnect = NULL;
+ FnSend mySend = NULL;
+ FnCloseSocket myClose = NULL;
+
+ WSADATA wsaData;
+ SOCKET soc;
+ struct sockaddr_in remote;
+
+ char kernel32Str[] = { 'k', 'e', 'r', 'n', 'e', 'l', '3', '2', '.', 'd', 'l', 'l', 0 };
+ char loadLibrary[] = { 'L', 'o', 'a', 'd', 'L', 'i', 'b', 'r', 'a', 'r', 'y', 'A', 0 };
+ char getProcAddress[] = { 'G', 'e', 't', 'P', 'r', 'o', 'c', 'A', 'd', 'd', 'r', 'e', 's', 's', 0 };
+ char sleep[] = { 'S', 'l', 'e', 'e', 'p', 0 };
+ char exitProcess[] = { 'E', 'x', 'i', 't', 'P', 'r', 'o', 'c', 'e', 's', 's', 0 };
+
+ char ws2_32dll[] = { 'W', 's', '2', '_', '3', '2', '.', 'd', 'l', 'l', 0 };
+ char wsaStartup[] = { 'W', 'S', 'A', 'S', 't', 'a', 'r', 't', 'u', 'p', 0 };
+ char wsaSocketA[] = { 'W', 'S', 'A', 'S', 'o', 'c', 'k', 'e', 't', 'A', 0 };
+ char connect[] = { 'c', 'o', 'n', 'n', 'e', 'c', 't', 0 };
+ char send[] = { 's', 'e', 'n', 'd', 0 };
+ char close[] = { 'c', 'l', 'o', 's', 'e', 's', 'o', 'c', 'k', 'e', 't', 0 };
+
+ kernel32 = GetKernel32DLL(GetPEB());
+
+ myGetProcAddress = (FnGetProcAddress)MemGetProcAddress(kernel32, getProcAddress);
+ myLoadLibrary = (FnLoadLibraryA)myGetProcAddress(kernel32, loadLibrary);
+
+ if (myLoadLibrary == NULL || myGetProcAddress == NULL) {
+ return 0;
+ }
+
+ mySleep = (FnSleep)myGetProcAddress(kernel32, sleep);
+ myExitProcess = (FnExitProcess)myGetProcAddress(kernel32, exitProcess);
+
+ HMODULE winsock = myLoadLibrary(ws2_32dll);
+ if (!winsock) {
+ myExitProcess(2);
+ }
+
+ myWSAStartup = (FnWSAStartup)myGetProcAddress(winsock, wsaStartup);
+ myWSASocketA = (FnWSASocketA)myGetProcAddress(winsock, wsaSocketA);
+ myConnect = (FnConnect)myGetProcAddress(winsock, connect);
+ mySend = (FnSend)myGetProcAddress(winsock, send);
+ myClose = (FnCloseSocket)myGetProcAddress(winsock, close);
+
+ if (myWSAStartup(MAKEWORD(2, 2), &wsaData) != 0) {
+ myExitProcess(3);
+ }
+
+ soc = myWSASocketA(AF_INET, SOCK_STREAM, IPPROTO_TCP, NULL, 0, 0);
+ if (soc == INVALID_SOCKET) {
+ myExitProcess(4);
+ }
+
+ remote.sin_family = AF_INET;
+ remote.sin_addr.s_addr = host;
+ remote.sin_port = port;
+
+ if (myConnect(soc, (SOCKADDR*)&remote, sizeof(remote))) {
+ myExitProcess(5);
+ }
+
+ if (mySend(soc, (char*)&nonce, sizeof(int), 0) == SOCKET_ERROR) {
+ myExitProcess(6);
+ }
+
+ // sleep for 100 milliseconds, so we know the send is going to complete
+ mySleep(100);
+
+ myClose(soc);
+
+ myExitProcess(0);
+
+ return 0;
+}
+
+PPEB GetPEB() {
+#if defined(_WIN64)
+ return (PPEB)__readgsqword(0x60);
+#else
+ return (PPEB)__readfsdword(0x30);
+#endif
+}
+
+wchar_t* mywcsistr(wchar_t* string, wchar_t* substring)
+{
+ wchar_t* a;
+ wchar_t* b;
+
+ if (*substring == 0)
+ {
+ return string;
+ }
+
+ while (*string != 0)
+ {
+ b = substring;
+
+ if (*string != *b && *string != (*b ^ 0x20))
+ {
+ *string++;
+ continue;
+ }
+ a = string;
+
+ while (*b != 0)
+ {
+ if (*a != *b && *a != (*b ^ 0x20))
+ {
+ break;
+ }
+
+ *a++;
+ *b++;
+
+ if (*b == 0)
+ {
+ return string;
+ }
+ }
+
+ *string++;
+ }
+ return NULL;
+}
+
+int mystrcmp(const char* string1, const char* string2)
+{
+
+ while(*string1 != 0 && (*string1 == *string2)) {
+ string1++;
+ string2++;
+ }
+
+ return *string1 - *string2;
+}
+
+PVOID GetKernel32DLL(PPEB ppeb) {
+ wchar_t kernel32[] = { 'K', 'E', 'R', 'N', 'E', 'L', '3', '2', '.', 'D', 'L', 'L', 0 };
+ PPEB_LDR_DATA pLdr = ppeb->Ldr;
+
+ PLIST_ENTRY pNextModule = &pLdr->InMemoryOrderModuleList;
+ PLIST_ENTRY pCurEntry = pNextModule->Flink;
+ PLDR_DATA_TABLE_ENTRY pDataTableEntry = CONTAINING_RECORD(pCurEntry, LDR_DATA_TABLE_ENTRY, InMemoryOrderLinks);
+
+ do {
+ if (mywcsistr(pDataTableEntry->FullDllName.Buffer, kernel32) != NULL) {
+ return pDataTableEntry->DllBase;
+ }
+ pNextModule = &(pDataTableEntry->InMemoryOrderLinks);
+ pCurEntry = pNextModule->Flink;
+ pDataTableEntry = CONTAINING_RECORD(pCurEntry, LDR_DATA_TABLE_ENTRY, InMemoryOrderLinks);
+ } while (pDataTableEntry->DllBase != NULL);
+ return NULL;
+}
+
+HMODULE MemGetProcAddress(PVOID pModule, PCSTR funcName) {
+ PIMAGE_NT_HEADERS pNTHeader = (PIMAGE_NT_HEADERS)((ULONG_PTR)pModule + ((PIMAGE_DOS_HEADER)pModule)->e_lfanew);
+ DWORD dwExportDirRVA = pNTHeader->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress;
+ if (dwExportDirRVA != 0) {
+ PIMAGE_EXPORT_DIRECTORY pExportsDir = (PIMAGE_EXPORT_DIRECTORY)(((ULONG_PTR)pModule) + dwExportDirRVA);
+ PDWORD pdwNameBase = (PDWORD)((ULONG_PTR)pModule + pExportsDir->AddressOfNames);
+ PWORD pdwOrdinalBase = (PWORD)((ULONG_PTR)pModule + pExportsDir->AddressOfNameOrdinals);
+ PDWORD pdwFunctionBase = (PDWORD)((ULONG_PTR)pModule + pExportsDir->AddressOfFunctions);
+ for (int i = 0; i < pExportsDir->NumberOfFunctions; i++) {
+ PCSTR pFunctionName = (PCSTR)(*pdwNameBase + (ULONG_PTR)pModule);
+ if (!mystrcmp(funcName, pFunctionName)) {
+ return (HMODULE)((ULONG_PTR)pModule + *((PDWORD)(pdwFunctionBase + *pdwOrdinalBase)));
+ }
+ pdwOrdinalBase++;
+ pdwNameBase++;
+ }
+ }
+ return NULL;
+}
+