//go:build windows package pluginhost import ( "context" "crypto/sha256" "encoding/hex" "errors" "fmt" "io" "os" "path/filepath" "runtime" "strings" "sync" "sync/atomic" "syscall" "unsafe" "golang.org/x/sys/windows") type windowsBuffer struct { ptr uintptr len uintptr} type windowsHostAPI struct { abiVersion uint32 hostCtx uintptr call uintptr freeBuffer uintptr} type windowsPluginAPI struct { abiVersion uint32 call uintptr freeBuffer uintptr shutdown uintptr} var ( windowsHostCallbackID atomic.Uintptr windowsHostCallbackEntries sync.Map windowsHostCallCallback = syscall.NewCallback(windowsHostCall) windowsHostFreeCallback = syscall.NewCallback(windowsHostFree) shadowPluginCleanupOnce sync.Once) const ( shadowPluginPrefix = "cliproxy-plugin-" shadowPluginTempPrefix = ".cliproxy-plugin-" shadowPluginProcessDirPrefix = "pid-" shadowPluginDigestLength = 32) type dynamicLibraryLoader struct{} type dynamicLibraryClient struct { dll *syscall.DLL tempPath string hostAPI *windowsHostAPI hostCtx *uintptr api windowsPluginAPI} func defaultPluginLoader() pluginLoader { return dynamicLibraryLoader{}} func (dynamicLibraryLoader) Open(file pluginFile, host *Host) (pluginClient, error) { loadPath, errShadow := shadowCopyPlugin(file) if errShadow != nil { return nil, errShadow } dll, errLoad := syscall.LoadDLL(loadPath) if errLoad != nil { removeShadowPlugin(loadPath) return nil, errLoad } proc, errProc := dll.FindProc("cliproxy_plugin_init") if errProc != nil { _ = dll.Release() removeShadowPlugin(loadPath) return nil, errProc } id := windowsHostCallbackID.Add(1) hostCtx := new(uintptr) *hostCtx = id windowsHostCallbackEntries.Store(id, dynamicHostCallbackEntry{host: host, pluginID: file.ID}) client := &dynamicLibraryClient{ dll: dll, tempPath: loadPath, hostCtx: hostCtx, hostAPI: &windowsHostAPI{ abiVersion: pluginHostABIVersion, hostCtx: uintptr(unsafe.Pointer(hostCtx)), call: windowsHostCallCallback, freeBuffer: windowsHostFreeCallback, }, } rc, _, errCall := proc.Call(uintptr(unsafe.Pointer(client.hostAPI)), uintptr(unsafe.Pointer(&client.api))) if rc != 0 { client.closeAfterOpenFailure() return nil, fmt.Errorf("cliproxy_plugin_init returned %d: %v", rc, errCall) } if client.api.abiVersion != pluginHostABIVersion { client.closeAfterOpenFailure() return nil, fmt.Errorf("plugin ABI version %d is not supported", client.api.abiVersion) } if client.api.call == 0 || client.api.freeBuffer == 0 { client.closeAfterOpenFailure() return nil, fmt.Errorf("plugin function table is incomplete") } return client, nil} func shadowCopyPlugin(file pluginFile) (string, error) { dir, errDir := shadowPluginDir() if errDir != nil { return "", errDir } shadowPluginCleanupOnce.Do(func() { removeStaleShadowPlugins(dir) }) return shadowCopyPluginToDir(file, dir)} func shadowCopyPluginToDir(file pluginFile, dir string) (string, error) { source := filepath.Clean(file.Path) tmp, errTemp := os.CreateTemp(dir, shadowPluginTempPrefix+file.ID+"-*"+filepath.Ext(source)) if errTemp != nil { return "", errTemp } tmpName := tmp.Name() removeTemp := true defer func() { if removeTemp { removeShadowPlugin(tmpName) } }() in, errOpen := os.Open(source) if errOpen != nil { _ = tmp.Close() return "", errOpen } defer func() { _ = in.Close() }() hasher := sha256.New() size, errCopy := io.Copy(io.MultiWriter(tmp, hasher), in) if errCopy != nil { _ = tmp.Close() return "", errCopy } if errClose := tmp.Close(); errClose != nil { return "", errClose } digest := hex.EncodeToString(hasher.Sum(nil)) target := shadowPluginPath(dir, file.ID, digest, filepath.Ext(source)) if shadowPluginMatches(target, size, digest) { return target, nil } if errRemove := os.Remove(target); errRemove != nil && !errors.Is(errRemove, os.ErrNotExist) { if shadowPluginMatches(target, size, digest) { return target, nil } removeShadowPlugin(target) return "", fmt.Errorf("remove stale shadow plugin: %w", errRemove) } if errRename := os.Rename(tmpName, target); errRename != nil { if shadowPluginMatches(target, size, digest) { return target, nil } return "", fmt.Errorf("move shadow plugin: %w", errRename) } removeTemp = false return target, nil} func shadowPluginDir() (string, error) { dir := filepath.Join(os.TempDir(), "cliproxy-pluginhost", shadowPluginProcessDirName(os.Getpid())) if errMkdir := os.MkdirAll(dir, 0o700); errMkdir != nil { return "", errMkdir } return dir, nil} func shadowPluginProcessDirName(pid int) string { return fmt.Sprintf("%s%d", shadowPluginProcessDirPrefix, pid)} func removeShadowPlugin(path string) { if path == "" { return } if errRemove := os.Remove(path); errRemove == nil { return } pathPtr, errPath := windows.UTF16PtrFromString(path) if errPath != nil { return } _ = windows.MoveFileEx(pathPtr, nil, windows.MOVEFILE_DELAY_UNTIL_REBOOT)} func removeStaleShadowPlugins(dir string) { entries, errRead := os.ReadDir(dir) if errRead != nil { return } for _, entry := range entries { if entry == nil || entry.IsDir() { continue } name := entry.Name() if strings.HasPrefix(name, shadowPluginPrefix) || strings.HasPrefix(name, shadowPluginTempPrefix) { removeShadowPlugin(filepath.Join(dir, name)) } }} func shadowPluginPath(dir string, id string, digest string, extension string) string { if len(digest) > shadowPluginDigestLength { digest = digest[:shadowPluginDigestLength] } return filepath.Join(dir, shadowPluginPrefix+id+"-"+digest+extension)} func shadowPluginMatches(path string, size int64, digest string) bool { info, errStat := os.Stat(path) if errStat != nil { return false } if !info.Mode().IsRegular() || info.Size() != size { return false } file, errOpen := os.Open(path) if errOpen != nil { return false } defer func() { _ = file.Close() }() hasher := sha256.New() if _, errCopy := io.Copy(hasher, file); errCopy != nil { return false } return hex.EncodeToString(hasher.Sum(nil)) == digest} func (c *dynamicLibraryClient) Call(ctx context.Context, method string, request []byte) ([]byte, error) { if c == nil || c.api.call == 0 { return nil, fmt.Errorf("plugin client is closed") } if ctx != nil { select { case <-ctx.Done(): return nil, ctx.Err() default: } } methodBytes, errMethod := syscall.BytePtrFromString(method) if errMethod != nil { return nil, errMethod } var requestPtr uintptr if len(request) > 0 { requestPtr = uintptr(unsafe.Pointer(&request[0])) } responseMem, errAlloc := windows.LocalAlloc( windows.LMEM_FIXED|windows.LMEM_ZEROINIT, uint32(unsafe.Sizeof(windowsBuffer{})), ) if errAlloc != nil { return nil, fmt.Errorf("allocate plugin response buffer: %w", errAlloc) } if responseMem == 0 { return nil, fmt.Errorf("allocate plugin response buffer") } defer func() { _, _ = windows.LocalFree(windows.Handle(responseMem)) }() response := (*windowsBuffer)(unsafe.Pointer(responseMem)) rc, _, _ := syscall.SyscallN( c.api.call, uintptr(unsafe.Pointer(methodBytes)), requestPtr, uintptr(len(request)), responseMem, ) runtime.KeepAlive(methodBytes) runtime.KeepAlive(request) var out []byte if response.ptr != 0 && response.len > 0 { out = unsafe.Slice((*byte)(unsafe.Pointer(response.ptr)), response.len) out = append([]byte(nil), out...) } if response.ptr != 0 { _, _, _ = syscall.SyscallN(c.api.freeBuffer, response.ptr, response.len) } if rc != 0 { if isPluginErrorEnvelope(out) { return out, nil } return nil, fmt.Errorf("plugin call %s returned %d: %s", method, rc, string(out)) } return out, nil} func (c *dynamicLibraryClient) Shutdown() { // Windows Go DLLs are not safe to hot-unload from the host process. // The plugin was loaded from a shadow copy, so keeping the module mapped // does not block deleting or replacing the source artifact. c.close(false)} func (c *dynamicLibraryClient) closeAfterOpenFailure() { c.close(true)} func (c *dynamicLibraryClient) close(releaseDLL bool) { if c == nil { return } if c.api.shutdown != 0 { _, _, _ = syscall.SyscallN(c.api.shutdown) c.api.shutdown = 0 } if c.hostCtx != nil { windowsHostCallbackEntries.Delete(*c.hostCtx) c.hostCtx = nil } if c.dll != nil { if releaseDLL { _ = c.dll.Release() } c.dll = nil } removeShadowPlugin(c.tempPath) c.tempPath = ""} func windowsHostCall(hostCtx uintptr, methodPtr uintptr, requestPtr uintptr, requestLen uintptr, responsePtr uintptr) uintptr { if responsePtr != 0 { response := (*windowsBuffer)(unsafe.Pointer(responsePtr)) response.ptr = 0 response.len = 0 } if hostCtx == 0 || methodPtr == 0 { return 1 } id := *(*uintptr)(unsafe.Pointer(hostCtx)) rawHost, okHost := windowsHostCallbackEntries.Load(id) if !okHost { return 1 } entry, okHost := rawHost.(dynamicHostCallbackEntry) if !okHost || entry.host == nil { return 1 } var request []byte if requestPtr != 0 && requestLen > 0 { request = unsafe.Slice((*byte)(unsafe.Pointer(requestPtr)), requestLen) request = append([]byte(nil), request...) } ctx := withHostCallbackPluginID(context.Background(), entry.pluginID) resp, errCall := entry.host.callFromPlugin(ctx, windowsString(methodPtr), request) if errCall != nil { resp = marshalRPCError("host_call_failed", errCall.Error()) } if len(resp) == 0 || responsePtr == 0 { return 0 } mem, errAlloc := windows.LocalAlloc(windows.LMEM_FIXED, uint32(len(resp))) if errAlloc != nil || mem == 0 { return 1 } copy(unsafe.Slice((*byte)(unsafe.Pointer(mem)), len(resp)), resp) response := (*windowsBuffer)(unsafe.Pointer(responsePtr)) response.ptr = mem response.len = uintptr(len(resp)) return 0} func windowsHostFree(ptr uintptr, len uintptr) uintptr { if ptr != 0 { _, _ = windows.LocalFree(windows.Handle(ptr)) } return 0} func windowsString(ptr uintptr) string { if ptr == 0 { return "" } bytes := make([]byte, 0) for offset := uintptr(0); ; offset++ { b := *(*byte)(unsafe.Pointer(ptr + offset)) if b == 0 { break } bytes = append(bytes, b) } return string(bytes)}
//go:build windows
package pluginhost
import (
"context"
"crypto/sha256"
"encoding/hex"
"errors"
"fmt"
"io"
"os"
"path/filepath"
"runtime"
"strings"
"sync"
"sync/atomic"
"syscall"
"unsafe"
"golang.org/x/sys/windows"
)
type windowsBuffer struct {
ptr uintptr
len uintptr
}
type windowsHostAPI struct {
abiVersion uint32
hostCtx uintptr
call uintptr
freeBuffer uintptr
}
type windowsPluginAPI struct {
abiVersion uint32
call uintptr
freeBuffer uintptr
shutdown uintptr
}
var (
windowsHostCallbackID atomic.Uintptr
windowsHostCallbackEntries sync.Map
windowsHostCallCallback = syscall.NewCallback(windowsHostCall)
windowsHostFreeCallback = syscall.NewCallback(windowsHostFree)
shadowPluginCleanupOnce sync.Once
)
const (
shadowPluginPrefix = "cliproxy-plugin-"
shadowPluginTempPrefix = ".cliproxy-plugin-"
shadowPluginProcessDirPrefix = "pid-"
shadowPluginDigestLength = 32
)
type dynamicLibraryLoader struct{}
type dynamicLibraryClient struct {
dll *syscall.DLL
tempPath string
hostAPI *windowsHostAPI
hostCtx *uintptr
api windowsPluginAPI
}
func defaultPluginLoader() pluginLoader {
return dynamicLibraryLoader{}
}
func (dynamicLibraryLoader) Open(file pluginFile, host *Host) (pluginClient, error) {
loadPath, errShadow := shadowCopyPlugin(file)
if errShadow != nil {
return nil, errShadow
}
dll, errLoad := syscall.LoadDLL(loadPath)
if errLoad != nil {
removeShadowPlugin(loadPath)
return nil, errLoad
}
proc, errProc := dll.FindProc("cliproxy_plugin_init")
if errProc != nil {
_ = dll.Release()
removeShadowPlugin(loadPath)
return nil, errProc
}
id := windowsHostCallbackID.Add(1)
hostCtx := new(uintptr)
*hostCtx = id
windowsHostCallbackEntries.Store(id, dynamicHostCallbackEntry{host: host, pluginID: file.ID})
client := &dynamicLibraryClient{
dll: dll,
tempPath: loadPath,
hostCtx: hostCtx,
hostAPI: &windowsHostAPI{
abiVersion: pluginHostABIVersion,
hostCtx: uintptr(unsafe.Pointer(hostCtx)),
call: windowsHostCallCallback,
freeBuffer: windowsHostFreeCallback,
},
}
rc, _, errCall := proc.Call(uintptr(unsafe.Pointer(client.hostAPI)), uintptr(unsafe.Pointer(&client.api)))
if rc != 0 {
client.closeAfterOpenFailure()
return nil, fmt.Errorf("cliproxy_plugin_init returned %d: %v", rc, errCall)
}
if client.api.abiVersion != pluginHostABIVersion {
client.closeAfterOpenFailure()
return nil, fmt.Errorf("plugin ABI version %d is not supported", client.api.abiVersion)
}
if client.api.call == 0 || client.api.freeBuffer == 0 {
client.closeAfterOpenFailure()
return nil, fmt.Errorf("plugin function table is incomplete")
}
return client, nil
}
func shadowCopyPlugin(file pluginFile) (string, error) {
dir, errDir := shadowPluginDir()
if errDir != nil {
return "", errDir
}
shadowPluginCleanupOnce.Do(func() {
removeStaleShadowPlugins(dir)
})
return shadowCopyPluginToDir(file, dir)
}
func shadowCopyPluginToDir(file pluginFile, dir string) (string, error) {
source := filepath.Clean(file.Path)
tmp, errTemp := os.CreateTemp(dir, shadowPluginTempPrefix+file.ID+"-*"+filepath.Ext(source))
if errTemp != nil {
return "", errTemp
}
tmpName := tmp.Name()
removeTemp := true
defer func() {
if removeTemp {
removeShadowPlugin(tmpName)
}
}()
in, errOpen := os.Open(source)
if errOpen != nil {
_ = tmp.Close()
return "", errOpen
}
defer func() {
_ = in.Close()
}()
hasher := sha256.New()
size, errCopy := io.Copy(io.MultiWriter(tmp, hasher), in)
if errCopy != nil {
_ = tmp.Close()
return "", errCopy
}
if errClose := tmp.Close(); errClose != nil {
return "", errClose
}
digest := hex.EncodeToString(hasher.Sum(nil))
target := shadowPluginPath(dir, file.ID, digest, filepath.Ext(source))
if shadowPluginMatches(target, size, digest) {
return target, nil
}
if errRemove := os.Remove(target); errRemove != nil && !errors.Is(errRemove, os.ErrNotExist) {
if shadowPluginMatches(target, size, digest) {
return target, nil
}
removeShadowPlugin(target)
return "", fmt.Errorf("remove stale shadow plugin: %w", errRemove)
}
if errRename := os.Rename(tmpName, target); errRename != nil {
if shadowPluginMatches(target, size, digest) {
return target, nil
}
return "", fmt.Errorf("move shadow plugin: %w", errRename)
}
removeTemp = false
return target, nil
}
func shadowPluginDir() (string, error) {
dir := filepath.Join(os.TempDir(), "cliproxy-pluginhost", shadowPluginProcessDirName(os.Getpid()))
if errMkdir := os.MkdirAll(dir, 0o700); errMkdir != nil {
return "", errMkdir
}
return dir, nil
}
func shadowPluginProcessDirName(pid int) string {
return fmt.Sprintf("%s%d", shadowPluginProcessDirPrefix, pid)
}
func removeShadowPlugin(path string) {
if path == "" {
return
}
if errRemove := os.Remove(path); errRemove == nil {
return
}
pathPtr, errPath := windows.UTF16PtrFromString(path)
if errPath != nil {
return
}
_ = windows.MoveFileEx(pathPtr, nil, windows.MOVEFILE_DELAY_UNTIL_REBOOT)
}
func removeStaleShadowPlugins(dir string) {
entries, errRead := os.ReadDir(dir)
if errRead != nil {
return
}
for _, entry := range entries {
if entry == nil || entry.IsDir() {
continue
}
name := entry.Name()
if strings.HasPrefix(name, shadowPluginPrefix) || strings.HasPrefix(name, shadowPluginTempPrefix) {
removeShadowPlugin(filepath.Join(dir, name))
}
}
}
func shadowPluginPath(dir string, id string, digest string, extension string) string {
if len(digest) > shadowPluginDigestLength {
digest = digest[:shadowPluginDigestLength]
}
return filepath.Join(dir, shadowPluginPrefix+id+"-"+digest+extension)
}
func shadowPluginMatches(path string, size int64, digest string) bool {
info, errStat := os.Stat(path)
if errStat != nil {
return false
}
if !info.Mode().IsRegular() || info.Size() != size {
return false
}
file, errOpen := os.Open(path)
if errOpen != nil {
return false
}
defer func() {
_ = file.Close()
}()
hasher := sha256.New()
if _, errCopy := io.Copy(hasher, file); errCopy != nil {
return false
}
return hex.EncodeToString(hasher.Sum(nil)) == digest
}
func (c *dynamicLibraryClient) Call(ctx context.Context, method string, request []byte) ([]byte, error) {
if c == nil || c.api.call == 0 {
return nil, fmt.Errorf("plugin client is closed")
}
if ctx != nil {
select {
case <-ctx.Done():
return nil, ctx.Err()
default:
}
}
methodBytes, errMethod := syscall.BytePtrFromString(method)
if errMethod != nil {
return nil, errMethod
}
var requestPtr uintptr
if len(request) > 0 {
requestPtr = uintptr(unsafe.Pointer(&request[0]))
}
responseMem, errAlloc := windows.LocalAlloc(
windows.LMEM_FIXED|windows.LMEM_ZEROINIT,
uint32(unsafe.Sizeof(windowsBuffer{})),
)
if errAlloc != nil {
return nil, fmt.Errorf("allocate plugin response buffer: %w", errAlloc)
}
if responseMem == 0 {
return nil, fmt.Errorf("allocate plugin response buffer")
}
defer func() {
_, _ = windows.LocalFree(windows.Handle(responseMem))
}()
response := (*windowsBuffer)(unsafe.Pointer(responseMem))
rc, _, _ := syscall.SyscallN(
c.api.call,
uintptr(unsafe.Pointer(methodBytes)),
requestPtr,
uintptr(len(request)),
responseMem,
)
runtime.KeepAlive(methodBytes)
runtime.KeepAlive(request)
var out []byte
if response.ptr != 0 && response.len > 0 {
out = unsafe.Slice((*byte)(unsafe.Pointer(response.ptr)), response.len)
out = append([]byte(nil), out...)
}
if response.ptr != 0 {
_, _, _ = syscall.SyscallN(c.api.freeBuffer, response.ptr, response.len)
}
if rc != 0 {
if isPluginErrorEnvelope(out) {
return out, nil
}
return nil, fmt.Errorf("plugin call %s returned %d: %s", method, rc, string(out))
}
return out, nil
}
func (c *dynamicLibraryClient) Shutdown() {
// Windows Go DLLs are not safe to hot-unload from the host process.
// The plugin was loaded from a shadow copy, so keeping the module mapped
// does not block deleting or replacing the source artifact.
c.close(false)
}
func (c *dynamicLibraryClient) closeAfterOpenFailure() {
c.close(true)
}
func (c *dynamicLibraryClient) close(releaseDLL bool) {
if c == nil {
return
}
if c.api.shutdown != 0 {
_, _, _ = syscall.SyscallN(c.api.shutdown)
c.api.shutdown = 0
}
if c.hostCtx != nil {
windowsHostCallbackEntries.Delete(*c.hostCtx)
c.hostCtx = nil
}
if c.dll != nil {
if releaseDLL {
_ = c.dll.Release()
}
c.dll = nil
}
removeShadowPlugin(c.tempPath)
c.tempPath = ""
}
func windowsHostCall(hostCtx uintptr, methodPtr uintptr, requestPtr uintptr, requestLen uintptr, responsePtr uintptr) uintptr {
if responsePtr != 0 {
response := (*windowsBuffer)(unsafe.Pointer(responsePtr))
response.ptr = 0
response.len = 0
}
if hostCtx == 0 || methodPtr == 0 {
return 1
}
id := *(*uintptr)(unsafe.Pointer(hostCtx))
rawHost, okHost := windowsHostCallbackEntries.Load(id)
if !okHost {
return 1
}
entry, okHost := rawHost.(dynamicHostCallbackEntry)
if !okHost || entry.host == nil {
return 1
}
var request []byte
if requestPtr != 0 && requestLen > 0 {
request = unsafe.Slice((*byte)(unsafe.Pointer(requestPtr)), requestLen)
request = append([]byte(nil), request...)
}
ctx := withHostCallbackPluginID(context.Background(), entry.pluginID)
resp, errCall := entry.host.callFromPlugin(ctx, windowsString(methodPtr), request)
if errCall != nil {
resp = marshalRPCError("host_call_failed", errCall.Error())
}
if len(resp) == 0 || responsePtr == 0 {
return 0
}
mem, errAlloc := windows.LocalAlloc(windows.LMEM_FIXED, uint32(len(resp)))
if errAlloc != nil || mem == 0 {
return 1
}
copy(unsafe.Slice((*byte)(unsafe.Pointer(mem)), len(resp)), resp)
response := (*windowsBuffer)(unsafe.Pointer(responsePtr))
response.ptr = mem
response.len = uintptr(len(resp))
return 0
}
func windowsHostFree(ptr uintptr, len uintptr) uintptr {
if ptr != 0 {
_, _ = windows.LocalFree(windows.Handle(ptr))
}
return 0
}
func windowsString(ptr uintptr) string {
if ptr == 0 {
return ""
}
bytes := make([]byte, 0)
for offset := uintptr(0); ; offset++ {
b := *(*byte)(unsafe.Pointer(ptr + offset))
if b == 0 {
break
}
bytes = append(bytes, b)
}
return string(bytes)
}