1// Copyright 2015 The Go Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style 3// license that can be found in the LICENSE file. 4 5//go:build windows 6 7package registry 8 9import ( 10 "errors" 11 "syscall" 12 "unicode/utf16" 13 "unsafe" 14) 15 16const ( 17 // Registry value types. 18 NONE = 0 19 SZ = 1 20 EXPAND_SZ = 2 21 BINARY = 3 22 DWORD = 4 23 DWORD_BIG_ENDIAN = 5 24 LINK = 6 25 MULTI_SZ = 7 26 RESOURCE_LIST = 8 27 FULL_RESOURCE_DESCRIPTOR = 9 28 RESOURCE_REQUIREMENTS_LIST = 10 29 QWORD = 11 30) 31 32var ( 33 // ErrShortBuffer is returned when the buffer was too short for the operation. 34 ErrShortBuffer = syscall.ERROR_MORE_DATA 35 36 // ErrNotExist is returned when a registry key or value does not exist. 37 ErrNotExist = syscall.ERROR_FILE_NOT_FOUND 38 39 // ErrUnexpectedType is returned by Get*Value when the value's type was unexpected. 40 ErrUnexpectedType = errors.New("unexpected key value type") 41) 42 43// GetValue retrieves the type and data for the specified value associated 44// with an open key k. It fills up buffer buf and returns the retrieved 45// byte count n. If buf is too small to fit the stored value it returns 46// ErrShortBuffer error along with the required buffer size n. 47// If no buffer is provided, it returns true and actual buffer size n. 48// If no buffer is provided, GetValue returns the value's type only. 49// If the value does not exist, the error returned is ErrNotExist. 50// 51// GetValue is a low level function. If value's type is known, use the appropriate 52// Get*Value function instead. 53func (k Key) GetValue(name string, buf []byte) (n int, valtype uint32, err error) { 54 pname, err := syscall.UTF16PtrFromString(name) 55 if err != nil { 56 return 0, 0, err 57 } 58 var pbuf *byte 59 if len(buf) > 0 { 60 pbuf = (*byte)(unsafe.Pointer(&buf[0])) 61 } 62 l := uint32(len(buf)) 63 err = syscall.RegQueryValueEx(syscall.Handle(k), pname, nil, &valtype, pbuf, &l) 64 if err != nil { 65 return int(l), valtype, err 66 } 67 return int(l), valtype, nil 68} 69 70func (k Key) getValue(name string, buf []byte) (date []byte, valtype uint32, err error) { 71 p, err := syscall.UTF16PtrFromString(name) 72 if err != nil { 73 return nil, 0, err 74 } 75 var t uint32 76 n := uint32(len(buf)) 77 for { 78 err = syscall.RegQueryValueEx(syscall.Handle(k), p, nil, &t, (*byte)(unsafe.Pointer(&buf[0])), &n) 79 if err == nil { 80 return buf[:n], t, nil 81 } 82 if err != syscall.ERROR_MORE_DATA { 83 return nil, 0, err 84 } 85 if n <= uint32(len(buf)) { 86 return nil, 0, err 87 } 88 buf = make([]byte, n) 89 } 90} 91 92// GetStringValue retrieves the string value for the specified 93// value name associated with an open key k. It also returns the value's type. 94// If value does not exist, GetStringValue returns ErrNotExist. 95// If value is not SZ or EXPAND_SZ, it will return the correct value 96// type and ErrUnexpectedType. 97func (k Key) GetStringValue(name string) (val string, valtype uint32, err error) { 98 data, typ, err2 := k.getValue(name, make([]byte, 64)) 99 if err2 != nil { 100 return "", typ, err2 101 } 102 switch typ { 103 case SZ, EXPAND_SZ: 104 default: 105 return "", typ, ErrUnexpectedType 106 } 107 if len(data) == 0 { 108 return "", typ, nil 109 } 110 u := (*[1 << 29]uint16)(unsafe.Pointer(&data[0]))[: len(data)/2 : len(data)/2] 111 return syscall.UTF16ToString(u), typ, nil 112} 113 114// GetMUIStringValue retrieves the localized string value for 115// the specified value name associated with an open key k. 116// If the value name doesn't exist or the localized string value 117// can't be resolved, GetMUIStringValue returns ErrNotExist. 118func (k Key) GetMUIStringValue(name string) (string, error) { 119 pname, err := syscall.UTF16PtrFromString(name) 120 if err != nil { 121 return "", err 122 } 123 124 buf := make([]uint16, 1024) 125 var buflen uint32 126 var pdir *uint16 127 128 err = regLoadMUIString(syscall.Handle(k), pname, &buf[0], uint32(len(buf)), &buflen, 0, pdir) 129 if err == syscall.ERROR_FILE_NOT_FOUND { // Try fallback path 130 131 // Try to resolve the string value using the system directory as 132 // a DLL search path; this assumes the string value is of the form 133 // @[path]\dllname,-strID but with no path given, e.g. @tzres.dll,-320. 134 135 // This approach works with tzres.dll but may have to be revised 136 // in the future to allow callers to provide custom search paths. 137 138 var s string 139 s, err = ExpandString("%SystemRoot%\\system32\\") 140 if err != nil { 141 return "", err 142 } 143 pdir, err = syscall.UTF16PtrFromString(s) 144 if err != nil { 145 return "", err 146 } 147 148 err = regLoadMUIString(syscall.Handle(k), pname, &buf[0], uint32(len(buf)), &buflen, 0, pdir) 149 } 150 151 for err == syscall.ERROR_MORE_DATA { // Grow buffer if needed 152 if buflen <= uint32(len(buf)) { 153 break // Buffer not growing, assume race; break 154 } 155 buf = make([]uint16, buflen) 156 err = regLoadMUIString(syscall.Handle(k), pname, &buf[0], uint32(len(buf)), &buflen, 0, pdir) 157 } 158 159 if err != nil { 160 return "", err 161 } 162 163 return syscall.UTF16ToString(buf), nil 164} 165 166// ExpandString expands environment-variable strings and replaces 167// them with the values defined for the current user. 168// Use ExpandString to expand EXPAND_SZ strings. 169func ExpandString(value string) (string, error) { 170 if value == "" { 171 return "", nil 172 } 173 p, err := syscall.UTF16PtrFromString(value) 174 if err != nil { 175 return "", err 176 } 177 r := make([]uint16, 100) 178 for { 179 n, err := expandEnvironmentStrings(p, &r[0], uint32(len(r))) 180 if err != nil { 181 return "", err 182 } 183 if n <= uint32(len(r)) { 184 return syscall.UTF16ToString(r[:n]), nil 185 } 186 r = make([]uint16, n) 187 } 188} 189 190// GetStringsValue retrieves the []string value for the specified 191// value name associated with an open key k. It also returns the value's type. 192// If value does not exist, GetStringsValue returns ErrNotExist. 193// If value is not MULTI_SZ, it will return the correct value 194// type and ErrUnexpectedType. 195func (k Key) GetStringsValue(name string) (val []string, valtype uint32, err error) { 196 data, typ, err2 := k.getValue(name, make([]byte, 64)) 197 if err2 != nil { 198 return nil, typ, err2 199 } 200 if typ != MULTI_SZ { 201 return nil, typ, ErrUnexpectedType 202 } 203 if len(data) == 0 { 204 return nil, typ, nil 205 } 206 p := (*[1 << 29]uint16)(unsafe.Pointer(&data[0]))[: len(data)/2 : len(data)/2] 207 if len(p) == 0 { 208 return nil, typ, nil 209 } 210 if p[len(p)-1] == 0 { 211 p = p[:len(p)-1] // remove terminating null 212 } 213 val = make([]string, 0, 5) 214 from := 0 215 for i, c := range p { 216 if c == 0 { 217 val = append(val, syscall.UTF16ToString(p[from:i])) 218 from = i + 1 219 } 220 } 221 return val, typ, nil 222} 223 224// GetIntegerValue retrieves the integer value for the specified 225// value name associated with an open key k. It also returns the value's type. 226// If value does not exist, GetIntegerValue returns ErrNotExist. 227// If value is not DWORD or QWORD, it will return the correct value 228// type and ErrUnexpectedType. 229func (k Key) GetIntegerValue(name string) (val uint64, valtype uint32, err error) { 230 data, typ, err2 := k.getValue(name, make([]byte, 8)) 231 if err2 != nil { 232 return 0, typ, err2 233 } 234 switch typ { 235 case DWORD: 236 if len(data) != 4 { 237 return 0, typ, errors.New("DWORD value is not 4 bytes long") 238 } 239 return uint64(*(*uint32)(unsafe.Pointer(&data[0]))), DWORD, nil 240 case QWORD: 241 if len(data) != 8 { 242 return 0, typ, errors.New("QWORD value is not 8 bytes long") 243 } 244 return *(*uint64)(unsafe.Pointer(&data[0])), QWORD, nil 245 default: 246 return 0, typ, ErrUnexpectedType 247 } 248} 249 250// GetBinaryValue retrieves the binary value for the specified 251// value name associated with an open key k. It also returns the value's type. 252// If value does not exist, GetBinaryValue returns ErrNotExist. 253// If value is not BINARY, it will return the correct value 254// type and ErrUnexpectedType. 255func (k Key) GetBinaryValue(name string) (val []byte, valtype uint32, err error) { 256 data, typ, err2 := k.getValue(name, make([]byte, 64)) 257 if err2 != nil { 258 return nil, typ, err2 259 } 260 if typ != BINARY { 261 return nil, typ, ErrUnexpectedType 262 } 263 return data, typ, nil 264} 265 266func (k Key) setValue(name string, valtype uint32, data []byte) error { 267 p, err := syscall.UTF16PtrFromString(name) 268 if err != nil { 269 return err 270 } 271 if len(data) == 0 { 272 return regSetValueEx(syscall.Handle(k), p, 0, valtype, nil, 0) 273 } 274 return regSetValueEx(syscall.Handle(k), p, 0, valtype, &data[0], uint32(len(data))) 275} 276 277// SetDWordValue sets the data and type of a name value 278// under key k to value and DWORD. 279func (k Key) SetDWordValue(name string, value uint32) error { 280 return k.setValue(name, DWORD, (*[4]byte)(unsafe.Pointer(&value))[:]) 281} 282 283// SetQWordValue sets the data and type of a name value 284// under key k to value and QWORD. 285func (k Key) SetQWordValue(name string, value uint64) error { 286 return k.setValue(name, QWORD, (*[8]byte)(unsafe.Pointer(&value))[:]) 287} 288 289func (k Key) setStringValue(name string, valtype uint32, value string) error { 290 v, err := syscall.UTF16FromString(value) 291 if err != nil { 292 return err 293 } 294 buf := (*[1 << 29]byte)(unsafe.Pointer(&v[0]))[: len(v)*2 : len(v)*2] 295 return k.setValue(name, valtype, buf) 296} 297 298// SetStringValue sets the data and type of a name value 299// under key k to value and SZ. The value must not contain a zero byte. 300func (k Key) SetStringValue(name, value string) error { 301 return k.setStringValue(name, SZ, value) 302} 303 304// SetExpandStringValue sets the data and type of a name value 305// under key k to value and EXPAND_SZ. The value must not contain a zero byte. 306func (k Key) SetExpandStringValue(name, value string) error { 307 return k.setStringValue(name, EXPAND_SZ, value) 308} 309 310// SetStringsValue sets the data and type of a name value 311// under key k to value and MULTI_SZ. The value strings 312// must not contain a zero byte. 313func (k Key) SetStringsValue(name string, value []string) error { 314 ss := "" 315 for _, s := range value { 316 for i := 0; i < len(s); i++ { 317 if s[i] == 0 { 318 return errors.New("string cannot have 0 inside") 319 } 320 } 321 ss += s + "\x00" 322 } 323 v := utf16.Encode([]rune(ss + "\x00")) 324 buf := (*[1 << 29]byte)(unsafe.Pointer(&v[0]))[: len(v)*2 : len(v)*2] 325 return k.setValue(name, MULTI_SZ, buf) 326} 327 328// SetBinaryValue sets the data and type of a name value 329// under key k to value and BINARY. 330func (k Key) SetBinaryValue(name string, value []byte) error { 331 return k.setValue(name, BINARY, value) 332} 333 334// DeleteValue removes a named value from the key k. 335func (k Key) DeleteValue(name string) error { 336 return regDeleteValue(syscall.Handle(k), syscall.StringToUTF16Ptr(name)) 337} 338 339// ReadValueNames returns the value names of key k. 340func (k Key) ReadValueNames() ([]string, error) { 341 ki, err := k.Stat() 342 if err != nil { 343 return nil, err 344 } 345 names := make([]string, 0, ki.ValueCount) 346 buf := make([]uint16, ki.MaxValueNameLen+1) // extra room for terminating null character 347loopItems: 348 for i := uint32(0); ; i++ { 349 l := uint32(len(buf)) 350 for { 351 err := regEnumValue(syscall.Handle(k), i, &buf[0], &l, nil, nil, nil, nil) 352 if err == nil { 353 break 354 } 355 if err == syscall.ERROR_MORE_DATA { 356 // Double buffer size and try again. 357 l = uint32(2 * len(buf)) 358 buf = make([]uint16, l) 359 continue 360 } 361 if err == _ERROR_NO_MORE_ITEMS { 362 break loopItems 363 } 364 return names, err 365 } 366 names = append(names, syscall.UTF16ToString(buf[:l])) 367 } 368 return names, nil 369} 370