tailscale/util/osdiag/osdiag_windows.go
Aaron Klotz 5fb1695bcb util/osdiag, util/osdiag/internal/wsc: add code to probe the Windows Security Center for installed software
The Windows Security Center is a component that manages the registration of
security products on a Windows system. Only products that have obtained a
special cert from Microsoft may register themselves using the WSC API.
Practically speaking, most vendors do in fact sign up for the program as it
enhances their legitimacy.

From our perspective, this is useful because it gives us a high-signal
source of information to query for the security products installed on the
system. I've tied this query into the osdiag package and is run during
bugreports.

It uses COM bindings that were automatically generated by my prototype
metadata processor, however that program still has a few bugs, so I had
to make a few manual tweaks. I dropped those binding into an internal
package because (for the moment, at least) they are effectively
purpose-built for the osdiag use case.

We also update the wingoes dependency to pick up BSTR.

Fixes #10646

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-08-24 11:51:18 -06:00

592 lines
14 KiB
Go

// Copyright (c) Tailscale Inc & AUTHORS
// SPDX-License-Identifier: BSD-3-Clause
package osdiag
import (
"encoding/binary"
"encoding/json"
"errors"
"fmt"
"io"
"path/filepath"
"strings"
"unicode/utf16"
"unsafe"
"github.com/dblohm7/wingoes/com"
"github.com/dblohm7/wingoes/pe"
"golang.org/x/sys/windows"
"golang.org/x/sys/windows/registry"
"tailscale.com/types/logger"
"tailscale.com/util/osdiag/internal/wsc"
"tailscale.com/util/winutil"
"tailscale.com/util/winutil/authenticode"
)
var (
errUnexpectedResult = errors.New("API call returned an unexpected value")
)
const (
maxBinaryValueLen = 128 // we'll truncate any binary values longer than this
maxRegValueNameLen = 16384 // maximum length supported by Windows + 1
initialValueBufLen = 80 // large enough to contain a stringified GUID encoded as UTF-16
)
func logSupportInfo(logf logger.Logf, reason LogSupportInfoReason) {
var b strings.Builder
if err := getSupportInfo(&b, reason); err != nil {
logf("error encoding support info: %v", err)
return
}
logf("%s", b.String())
}
const (
supportInfoKeyModules = "modules"
supportInfoKeyRegistry = "registry"
supportInfoKeySecurity = "securitySoftware"
supportInfoKeyWinsockLSP = "winsockLSP"
)
func getSupportInfo(w io.Writer, reason LogSupportInfoReason) error {
output := make(map[string]any)
regInfo, err := getRegistrySupportInfo(registry.LOCAL_MACHINE, []string{`SOFTWARE\Policies\Tailscale`, winutil.RegBase})
if err == nil {
output[supportInfoKeyRegistry] = regInfo
} else {
output[supportInfoKeyRegistry] = err
}
if reason == LogSupportInfoReasonBugReport {
modInfo, err := getModuleInfo()
if err == nil {
output[supportInfoKeyModules] = modInfo
} else {
output[supportInfoKeyModules] = err
}
output[supportInfoKeySecurity] = getSecurityInfo()
lspInfo, err := getWinsockLSPInfo()
if err == nil {
output[supportInfoKeyWinsockLSP] = lspInfo
} else {
output[supportInfoKeyWinsockLSP] = err
}
}
enc := json.NewEncoder(w)
return enc.Encode(output)
}
type getRegistrySupportInfoBufs struct {
nameBuf []uint16
valueBuf []byte
}
func getRegistrySupportInfo(root registry.Key, subKeys []string) (map[string]any, error) {
bufs := getRegistrySupportInfoBufs{
nameBuf: make([]uint16, maxRegValueNameLen),
valueBuf: make([]byte, initialValueBufLen),
}
output := make(map[string]any)
for _, subKey := range subKeys {
if err := getRegSubKey(root, subKey, 5, &bufs, output); err != nil && !errors.Is(err, registry.ErrNotExist) {
return nil, fmt.Errorf("getRegistrySupportInfo: %w", err)
}
}
return output, nil
}
func keyString(key registry.Key, subKey string) string {
var keyStr string
switch key {
case registry.CLASSES_ROOT:
keyStr = `HKCR\`
case registry.CURRENT_USER:
keyStr = `HKCU\`
case registry.LOCAL_MACHINE:
keyStr = `HKLM\`
case registry.USERS:
keyStr = `HKU\`
case registry.CURRENT_CONFIG:
keyStr = `HKCC\`
case registry.PERFORMANCE_DATA:
keyStr = `HKPD\`
default:
}
return keyStr + subKey
}
func getRegSubKey(key registry.Key, subKey string, recursionLimit int, bufs *getRegistrySupportInfoBufs, output map[string]any) error {
keyStr := keyString(key, subKey)
k, err := registry.OpenKey(key, subKey, registry.READ)
if err != nil {
return fmt.Errorf("opening %q: %w", keyStr, err)
}
defer k.Close()
kv := make(map[string]any)
index := uint32(0)
loopValues:
for {
nbuf := bufs.nameBuf
nameLen := uint32(len(nbuf))
valueType := uint32(0)
vbuf := bufs.valueBuf
valueLen := uint32(len(vbuf))
err := regEnumValue(k, index, &nbuf[0], &nameLen, nil, &valueType, &vbuf[0], &valueLen)
switch err {
case windows.ERROR_NO_MORE_ITEMS:
break loopValues
case windows.ERROR_MORE_DATA:
bufs.valueBuf = make([]byte, valueLen)
continue
case nil:
default:
return fmt.Errorf("regEnumValue: %w", err)
}
var value any
switch valueType {
case registry.SZ, registry.EXPAND_SZ:
value = windows.UTF16PtrToString((*uint16)(unsafe.Pointer(&vbuf[0])))
case registry.BINARY:
if valueLen > maxBinaryValueLen {
valueLen = maxBinaryValueLen
}
value = append([]byte{}, vbuf[:valueLen]...)
case registry.DWORD:
value = binary.LittleEndian.Uint32(vbuf[:4])
case registry.MULTI_SZ:
// Adapted from x/sys/windows/registry/(Key).GetStringsValue
p := (*[1 << 29]uint16)(unsafe.Pointer(&vbuf[0]))[: valueLen/2 : valueLen/2]
var strs []string
if len(p) > 0 {
if p[len(p)-1] == 0 {
p = p[:len(p)-1]
}
strs = make([]string, 0, 5)
from := 0
for i, c := range p {
if c == 0 {
strs = append(strs, string(utf16.Decode(p[from:i])))
from = i + 1
}
}
}
value = strs
case registry.QWORD:
value = binary.LittleEndian.Uint64(vbuf[:8])
default:
value = fmt.Sprintf("<unsupported value type %d>", valueType)
}
kv[windows.UTF16PtrToString(&nbuf[0])] = value
index++
}
if recursionLimit > 0 {
if sks, err := k.ReadSubKeyNames(0); err == nil {
for _, sk := range sks {
if err := getRegSubKey(k, sk, recursionLimit-1, bufs, kv); err != nil {
return err
}
}
}
}
output[keyStr] = kv
return nil
}
type moduleInfo struct {
path string `json:"-"` // internal use only
BaseAddress uintptr `json:"baseAddress"`
Size uint32 `json:"size"`
DebugInfo map[string]string `json:"debugInfo,omitempty"` // map for JSON marshaling purposes
DebugInfoErr error `json:"debugInfoErr,omitempty"`
Signature map[string]string `json:"signature,omitempty"` // map for JSON marshaling purposes
SignatureErr error `json:"signatureErr,omitempty"`
VersionInfo map[string]string `json:"versionInfo,omitempty"` // map for JSON marshaling purposes
VersionErr error `json:"versionErr,omitempty"`
}
func (mi *moduleInfo) setVersionInfo() {
vi, err := pe.NewVersionInfo(mi.path)
if err != nil {
if !errors.Is(err, pe.ErrNotPresent) {
mi.VersionErr = err
}
return
}
info := map[string]string{
"": vi.VersionNumber().String(),
}
ci, err := vi.Field("CompanyName")
if err == nil {
info["companyName"] = ci
}
mi.VersionInfo = info
}
var errAssertingType = errors.New("asserting DataDirectory type")
func (mi *moduleInfo) setDebugInfo() {
pem, err := pe.NewPEFromBaseAddressAndSize(mi.BaseAddress, mi.Size)
if err != nil {
mi.DebugInfoErr = err
return
}
defer pem.Close()
debugDirAny, err := pem.DataDirectoryEntry(pe.IMAGE_DIRECTORY_ENTRY_DEBUG)
if err != nil {
if !errors.Is(err, pe.ErrNotPresent) {
mi.DebugInfoErr = err
}
return
}
debugDir, ok := debugDirAny.([]pe.IMAGE_DEBUG_DIRECTORY)
if !ok {
mi.DebugInfoErr = errAssertingType
return
}
for _, dde := range debugDir {
if dde.Type != pe.IMAGE_DEBUG_TYPE_CODEVIEW {
continue
}
cv, err := pem.ExtractCodeViewInfo(dde)
if err == nil {
mi.DebugInfo = map[string]string{
"id": cv.String(),
"pdb": strings.ToLower(filepath.Base(cv.PDBPath)),
}
} else {
mi.DebugInfoErr = err
}
return
}
}
func (mi *moduleInfo) setAuthenticodeInfo() {
certSubject, provenance, err := authenticode.QueryCertSubject(mi.path)
if err != nil {
if !errors.Is(err, authenticode.ErrSigNotFound) {
mi.SignatureErr = err
}
return
}
sigInfo := map[string]string{
"subject": certSubject,
}
switch provenance {
case authenticode.SigProvEmbedded:
sigInfo["provenance"] = "embedded"
case authenticode.SigProvCatalog:
sigInfo["provenance"] = "catalog"
default:
}
mi.Signature = sigInfo
}
func getModuleInfo() (map[string]moduleInfo, error) {
// Take a snapshot of all modules currently loaded into the current process
snap, err := windows.CreateToolhelp32Snapshot(windows.TH32CS_SNAPMODULE, 0)
if err != nil {
return nil, err
}
defer windows.CloseHandle(snap)
result := make(map[string]moduleInfo)
me := windows.ModuleEntry32{
Size: uint32(unsafe.Sizeof(windows.ModuleEntry32{})),
}
// Now walk the list
for merr := windows.Module32First(snap, &me); merr == nil; merr = windows.Module32Next(snap, &me) {
name := strings.ToLower(windows.UTF16ToString(me.Module[:]))
path := windows.UTF16ToString(me.ExePath[:])
base := me.ModBaseAddr
size := me.ModBaseSize
entry := moduleInfo{
path: path,
BaseAddress: base,
Size: size,
}
entry.setVersionInfo()
entry.setDebugInfo()
entry.setAuthenticodeInfo()
result[name] = entry
}
return result, nil
}
type _WSC_PROVIDER_INFO_TYPE int32
const (
providerInfoLspCategories _WSC_PROVIDER_INFO_TYPE = 0
)
const (
_SOCKET_ERROR = -1
)
// Note that wsaProtocolInfo needs to be identical to windows.WSAProtocolInfo;
// the purpose of this type is to have the ability to use it as a reciever in
// the path and categoryFlags funcs defined below.
type wsaProtocolInfo windows.WSAProtocolInfo
func (pi *wsaProtocolInfo) path() (string, error) {
var errno int32
var buf [windows.MAX_PATH]uint16
bufCount := int32(len(buf))
ret := wscGetProviderPath(&pi.ProviderId, &buf[0], &bufCount, &errno)
if ret == _SOCKET_ERROR {
return "", windows.Errno(errno)
}
if ret != 0 {
return "", errUnexpectedResult
}
return windows.UTF16ToString(buf[:bufCount]), nil
}
func (pi *wsaProtocolInfo) categoryFlags() (uint32, error) {
var errno int32
var result uint32
bufLen := uintptr(unsafe.Sizeof(result))
ret := wscGetProviderInfo(&pi.ProviderId, providerInfoLspCategories, unsafe.Pointer(&result), &bufLen, 0, &errno)
if ret == _SOCKET_ERROR {
return 0, windows.Errno(errno)
}
if ret != 0 {
return 0, errUnexpectedResult
}
return result, nil
}
type wsaProtocolInfoOutput struct {
Description string `json:"description,omitempty"`
Version int32 `json:"version"`
AddressFamily int32 `json:"addressFamily"`
SocketType int32 `json:"socketType"`
Protocol int32 `json:"protocol"`
ServiceFlags1 string `json:"serviceFlags1"`
ProviderFlags string `json:"providerFlags"`
Path string `json:"path,omitempty"`
PathErr error `json:"pathErr,omitempty"`
Category string `json:"category,omitempty"`
CategoryErr error `json:"categoryErr,omitempty"`
BaseProviderID string `json:"baseProviderID,omitempty"`
LayerProviderID string `json:"layerProviderID,omitempty"`
Chain []uint32 `json:"chain,omitempty"`
}
func getWinsockLSPInfo() (map[uint32]wsaProtocolInfoOutput, error) {
protocols, err := enumWinsockProtocols()
if err != nil {
return nil, err
}
result := make(map[uint32]wsaProtocolInfoOutput, len(protocols))
for _, p := range protocols {
v := wsaProtocolInfoOutput{
Description: windows.UTF16ToString(p.ProtocolName[:]),
Version: p.Version,
AddressFamily: p.AddressFamily,
SocketType: p.SocketType,
Protocol: p.Protocol,
ServiceFlags1: fmt.Sprintf("0x%08X", p.ServiceFlags1), // Serializing as hex string to make the flags easier to decode by human inspection
ProviderFlags: fmt.Sprintf("0x%08X", p.ProviderFlags),
}
switch p.ProtocolChain.ChainLen {
case windows.BASE_PROTOCOL:
v.BaseProviderID = p.ProviderId.String()
case windows.LAYERED_PROTOCOL:
v.LayerProviderID = p.ProviderId.String()
default:
v.Chain = p.ProtocolChain.ChainEntries[:p.ProtocolChain.ChainLen]
}
// Queries that are only valid for base and layered protocols (not chains)
if v.Chain == nil {
path, err := p.path()
if err == nil {
v.Path = strings.ToLower(path)
} else {
v.PathErr = err
}
category, err := p.categoryFlags()
if err == nil {
v.Category = fmt.Sprintf("0x%08X", category)
} else if !errors.Is(err, windows.WSAEINVALIDPROVIDER) {
// WSAEINVALIDPROVIDER == "no category info found", so we only log
// errors other than that one.
v.CategoryErr = err
}
}
// Chains reference other providers using catalog entry IDs, so we use that
// value as the key in our map.
result[p.CatalogEntryId] = v
}
return result, nil
}
func enumWinsockProtocols() ([]wsaProtocolInfo, error) {
// Get the required size
var errno int32
var bytesReqd uint32
ret := wscEnumProtocols(nil, nil, &bytesReqd, &errno)
if ret != _SOCKET_ERROR {
return nil, errUnexpectedResult
}
if e := windows.Errno(errno); e != windows.WSAENOBUFS {
return nil, e
}
// Allocate
szEntry := uint32(unsafe.Sizeof(wsaProtocolInfo{}))
buf := make([]wsaProtocolInfo, bytesReqd/szEntry)
// Now do the query for real
bufLen := uint32(len(buf)) * szEntry
ret = wscEnumProtocols(nil, &buf[0], &bufLen, &errno)
if ret == _SOCKET_ERROR {
return nil, windows.Errno(errno)
}
return buf, nil
}
type providerKey struct {
provType wsc.WSC_SECURITY_PROVIDER
provKey string
}
var providerKeys = []providerKey{
providerKey{
wsc.WSC_SECURITY_PROVIDER_ANTIVIRUS,
"av",
},
providerKey{
wsc.WSC_SECURITY_PROVIDER_ANTISPYWARE,
"antispy",
},
providerKey{
wsc.WSC_SECURITY_PROVIDER_FIREWALL,
"firewall",
},
}
const (
maxProvCount = 100
)
type secProductInfo struct {
Name string `json:"name,omitempty"`
NameErr error `json:"nameErr,omitempty"`
State string `json:"state,omitempty"`
StateErr error `json:"stateErr,omitempty"`
}
func getSecurityInfo() map[string]any {
result := make(map[string]any)
for _, prov := range providerKeys {
// Note that we need to obtain a new product list for each provider type;
// the docs clearly state that we cannot reuse objects.
productList, err := com.CreateInstance[wsc.WSCProductList](wsc.CLSID_WSCProductList)
if err != nil {
result[prov.provKey] = err
continue
}
err = productList.Initialize(prov.provType)
if err != nil {
result[prov.provKey] = err
continue
}
n, err := productList.GetCount()
if err != nil {
result[prov.provKey] = err
continue
}
if n == 0 {
continue
}
n = min(n, maxProvCount)
values := make([]any, 0, n)
for i := int32(0); i < n; i++ {
product, err := productList.GetItem(uint32(i))
if err != nil {
values = append(values, err)
continue
}
var value secProductInfo
value.Name, err = product.GetProductName()
if err != nil {
value.NameErr = err
}
state, err := product.GetProductState()
if err == nil {
switch state {
case wsc.WSC_SECURITY_PRODUCT_STATE_ON:
value.State = "on"
case wsc.WSC_SECURITY_PRODUCT_STATE_OFF:
value.State = "off"
case wsc.WSC_SECURITY_PRODUCT_STATE_SNOOZED:
value.State = "snoozed"
case wsc.WSC_SECURITY_PRODUCT_STATE_EXPIRED:
value.State = "expired"
default:
value.State = fmt.Sprintf("<unknown state value %d>", state)
}
} else {
value.StateErr = err
}
values = append(values, value)
}
result[prov.provKey] = values
}
return result
}