mirror of
https://github.com/go-gitea/gitea.git
synced 2024-08-22 12:33:27 +02:00
565 lines
14 KiB
Go
565 lines
14 KiB
Go
// Copyright 2011 The Go Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package packet
|
|
|
|
import (
|
|
"bytes"
|
|
"crypto/cipher"
|
|
"crypto/dsa"
|
|
"crypto/ecdsa"
|
|
"crypto/sha1"
|
|
"fmt"
|
|
"io"
|
|
"io/ioutil"
|
|
"math/big"
|
|
"strconv"
|
|
"time"
|
|
|
|
"github.com/keybase/go-crypto/ed25519"
|
|
"github.com/keybase/go-crypto/openpgp/ecdh"
|
|
"github.com/keybase/go-crypto/openpgp/elgamal"
|
|
"github.com/keybase/go-crypto/openpgp/errors"
|
|
"github.com/keybase/go-crypto/openpgp/s2k"
|
|
"github.com/keybase/go-crypto/rsa"
|
|
)
|
|
|
|
// PrivateKey represents a possibly encrypted private key. See RFC 4880,
|
|
// section 5.5.3.
|
|
type PrivateKey struct {
|
|
PublicKey
|
|
Encrypted bool // if true then the private key is unavailable until Decrypt has been called.
|
|
encryptedData []byte
|
|
cipher CipherFunction
|
|
s2k func(out, in []byte)
|
|
PrivateKey interface{} // An *rsa.PrivateKey or *dsa.PrivateKey.
|
|
sha1Checksum bool
|
|
iv []byte
|
|
s2kHeader []byte
|
|
}
|
|
|
|
type EdDSAPrivateKey struct {
|
|
PrivateKey
|
|
seed parsedMPI
|
|
}
|
|
|
|
func (e *EdDSAPrivateKey) Seed() []byte {
|
|
return e.seed.bytes
|
|
}
|
|
|
|
func (e *EdDSAPrivateKey) Sign(digest []byte) (R, S []byte, err error) {
|
|
r := bytes.NewReader(e.seed.bytes)
|
|
publicKey, privateKey, err := ed25519.GenerateKey(r)
|
|
if err != nil {
|
|
return nil, nil, err
|
|
}
|
|
|
|
if !bytes.Equal(publicKey, e.PublicKey.edk.p.bytes[1:]) { // [1:] because [0] is 0x40 mpi header
|
|
return nil, nil, errors.UnsupportedError("EdDSA: Private key does not match public key.")
|
|
}
|
|
|
|
sig := ed25519.Sign(privateKey, digest)
|
|
|
|
sigLen := ed25519.SignatureSize / 2
|
|
return sig[:sigLen], sig[sigLen:], nil
|
|
}
|
|
|
|
func NewRSAPrivateKey(currentTime time.Time, priv *rsa.PrivateKey) *PrivateKey {
|
|
pk := new(PrivateKey)
|
|
pk.PublicKey = *NewRSAPublicKey(currentTime, &priv.PublicKey)
|
|
pk.PrivateKey = priv
|
|
return pk
|
|
}
|
|
|
|
func NewDSAPrivateKey(currentTime time.Time, priv *dsa.PrivateKey) *PrivateKey {
|
|
pk := new(PrivateKey)
|
|
pk.PublicKey = *NewDSAPublicKey(currentTime, &priv.PublicKey)
|
|
pk.PrivateKey = priv
|
|
return pk
|
|
}
|
|
|
|
func NewElGamalPrivateKey(currentTime time.Time, priv *elgamal.PrivateKey) *PrivateKey {
|
|
pk := new(PrivateKey)
|
|
pk.PublicKey = *NewElGamalPublicKey(currentTime, &priv.PublicKey)
|
|
pk.PrivateKey = priv
|
|
return pk
|
|
}
|
|
|
|
func NewECDSAPrivateKey(currentTime time.Time, priv *ecdsa.PrivateKey) *PrivateKey {
|
|
pk := new(PrivateKey)
|
|
pk.PublicKey = *NewECDSAPublicKey(currentTime, &priv.PublicKey)
|
|
pk.PrivateKey = priv
|
|
return pk
|
|
}
|
|
|
|
func NewECDHPrivateKey(currentTime time.Time, priv *ecdh.PrivateKey) *PrivateKey {
|
|
pk := new(PrivateKey)
|
|
pk.PublicKey = *NewECDHPublicKey(currentTime, &priv.PublicKey)
|
|
pk.PrivateKey = priv
|
|
return pk
|
|
}
|
|
|
|
func (pk *PrivateKey) parse(r io.Reader) (err error) {
|
|
err = (&pk.PublicKey).parse(r)
|
|
if err != nil {
|
|
return
|
|
}
|
|
var buf [1]byte
|
|
_, err = readFull(r, buf[:])
|
|
if err != nil {
|
|
return
|
|
}
|
|
|
|
s2kType := buf[0]
|
|
|
|
switch s2kType {
|
|
case 0:
|
|
pk.s2k = nil
|
|
pk.Encrypted = false
|
|
case 254, 255:
|
|
_, err = readFull(r, buf[:])
|
|
if err != nil {
|
|
return
|
|
}
|
|
pk.cipher = CipherFunction(buf[0])
|
|
pk.Encrypted = true
|
|
pk.s2k, err = s2k.Parse(r)
|
|
if err != nil {
|
|
return
|
|
}
|
|
if s2kType == 254 {
|
|
pk.sha1Checksum = true
|
|
}
|
|
// S2K == nil implies that we got a "GNU Dummy" S2K. For instance,
|
|
// because our master secret key is on a USB key in a vault somewhere.
|
|
// In that case, there is no further data to consume here.
|
|
if pk.s2k == nil {
|
|
pk.Encrypted = false
|
|
return
|
|
}
|
|
default:
|
|
return errors.UnsupportedError("deprecated s2k function in private key")
|
|
}
|
|
if pk.Encrypted {
|
|
blockSize := pk.cipher.blockSize()
|
|
if blockSize == 0 {
|
|
return errors.UnsupportedError("unsupported cipher in private key: " + strconv.Itoa(int(pk.cipher)))
|
|
}
|
|
pk.iv = make([]byte, blockSize)
|
|
_, err = readFull(r, pk.iv)
|
|
if err != nil {
|
|
return
|
|
}
|
|
}
|
|
|
|
pk.encryptedData, err = ioutil.ReadAll(r)
|
|
if err != nil {
|
|
return
|
|
}
|
|
|
|
if !pk.Encrypted {
|
|
return pk.parsePrivateKey(pk.encryptedData)
|
|
}
|
|
|
|
return
|
|
}
|
|
|
|
func mod64kHash(d []byte) uint16 {
|
|
var h uint16
|
|
for _, b := range d {
|
|
h += uint16(b)
|
|
}
|
|
return h
|
|
}
|
|
|
|
// Encrypt is the counterpart to the Decrypt() method below. It encrypts
|
|
// the private key with the provided passphrase. If config is nil, then
|
|
// the standard, and sensible, defaults apply.
|
|
//
|
|
// A key will be derived from the given passphrase using S2K Specifier
|
|
// Type 3 (Iterated + Salted, see RFC-4880 Sec. 3.7.1.3). This choice
|
|
// is hardcoded in s2k.Serialize(). S2KCount is hardcoded to 0, which is
|
|
// equivalent to 65536. And the hash algorithm for key-derivation can be
|
|
// set with config. The encrypted PrivateKey, using the algorithm specified
|
|
// in config (if provided), is written out to the encryptedData member.
|
|
// When Serialize() is called, this encryptedData member will be
|
|
// serialized, using S2K Usage value of 254, and thus SHA1 checksum.
|
|
func (pk *PrivateKey) Encrypt(passphrase []byte, config *Config) (err error) {
|
|
if pk.PrivateKey == nil {
|
|
return errors.InvalidArgumentError("there is no private key to encrypt")
|
|
}
|
|
|
|
pk.sha1Checksum = true
|
|
pk.cipher = config.Cipher()
|
|
s2kConfig := s2k.Config{
|
|
Hash: config.Hash(),
|
|
S2KCount: 0,
|
|
}
|
|
s2kBuf := bytes.NewBuffer(nil)
|
|
derivedKey := make([]byte, pk.cipher.KeySize())
|
|
err = s2k.Serialize(s2kBuf, derivedKey, config.Random(), passphrase, &s2kConfig)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
pk.s2kHeader = s2kBuf.Bytes()
|
|
// No good way to set pk.s2k but to call s2k.Parse(),
|
|
// even though we have all the information here, but
|
|
// most of the functions needed are private to s2k.
|
|
pk.s2k, err = s2k.Parse(s2kBuf)
|
|
pk.iv = make([]byte, pk.cipher.blockSize())
|
|
if _, err = config.Random().Read(pk.iv); err != nil {
|
|
return err
|
|
}
|
|
|
|
privateKeyBuf := bytes.NewBuffer(nil)
|
|
if err = pk.serializePrivateKey(privateKeyBuf); err != nil {
|
|
return err
|
|
}
|
|
|
|
checksum := sha1.Sum(privateKeyBuf.Bytes())
|
|
if _, err = privateKeyBuf.Write(checksum[:]); err != nil {
|
|
return err
|
|
}
|
|
|
|
pkData := privateKeyBuf.Bytes()
|
|
block := pk.cipher.new(derivedKey)
|
|
pk.encryptedData = make([]byte, len(pkData))
|
|
cfb := cipher.NewCFBEncrypter(block, pk.iv)
|
|
cfb.XORKeyStream(pk.encryptedData, pkData)
|
|
pk.Encrypted = true
|
|
return nil
|
|
}
|
|
|
|
func (pk *PrivateKey) Serialize(w io.Writer) (err error) {
|
|
buf := bytes.NewBuffer(nil)
|
|
err = pk.PublicKey.serializeWithoutHeaders(buf)
|
|
if err != nil {
|
|
return
|
|
}
|
|
|
|
privateKeyBuf := bytes.NewBuffer(nil)
|
|
|
|
if pk.PrivateKey == nil {
|
|
_, err = buf.Write([]byte{
|
|
254, // SHA-1 Convention
|
|
9, // Encryption scheme (AES256)
|
|
101, // GNU Extensions
|
|
2, // Hash value (SHA1)
|
|
'G', 'N', 'U', // "GNU" as a string
|
|
1, // Extension type 1001 (minus 1000)
|
|
})
|
|
} else if pk.Encrypted {
|
|
_, err = buf.Write([]byte{
|
|
254, // SHA-1 Convention
|
|
byte(pk.cipher), // Encryption scheme
|
|
})
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if _, err = buf.Write(pk.s2kHeader); err != nil {
|
|
return err
|
|
}
|
|
if _, err = buf.Write(pk.iv); err != nil {
|
|
return err
|
|
}
|
|
if _, err = privateKeyBuf.Write(pk.encryptedData); err != nil {
|
|
return err
|
|
}
|
|
} else {
|
|
buf.WriteByte(0 /* no encryption */)
|
|
if err = pk.serializePrivateKey(privateKeyBuf); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
ptype := packetTypePrivateKey
|
|
contents := buf.Bytes()
|
|
privateKeyBytes := privateKeyBuf.Bytes()
|
|
if pk.IsSubkey {
|
|
ptype = packetTypePrivateSubkey
|
|
}
|
|
totalLen := len(contents) + len(privateKeyBytes)
|
|
if !pk.Encrypted {
|
|
totalLen += 2
|
|
}
|
|
err = serializeHeader(w, ptype, totalLen)
|
|
if err != nil {
|
|
return
|
|
}
|
|
_, err = w.Write(contents)
|
|
if err != nil {
|
|
return
|
|
}
|
|
_, err = w.Write(privateKeyBytes)
|
|
if err != nil {
|
|
return
|
|
}
|
|
|
|
if len(privateKeyBytes) > 0 && !pk.Encrypted {
|
|
checksum := mod64kHash(privateKeyBytes)
|
|
var checksumBytes [2]byte
|
|
checksumBytes[0] = byte(checksum >> 8)
|
|
checksumBytes[1] = byte(checksum)
|
|
_, err = w.Write(checksumBytes[:])
|
|
}
|
|
|
|
return
|
|
}
|
|
|
|
func (pk *PrivateKey) serializePrivateKey(w io.Writer) (err error) {
|
|
switch priv := pk.PrivateKey.(type) {
|
|
case *rsa.PrivateKey:
|
|
err = serializeRSAPrivateKey(w, priv)
|
|
case *dsa.PrivateKey:
|
|
err = serializeDSAPrivateKey(w, priv)
|
|
case *elgamal.PrivateKey:
|
|
err = serializeElGamalPrivateKey(w, priv)
|
|
case *ecdsa.PrivateKey:
|
|
err = serializeECDSAPrivateKey(w, priv)
|
|
case *ecdh.PrivateKey:
|
|
err = serializeECDHPrivateKey(w, priv)
|
|
case *EdDSAPrivateKey:
|
|
err = serializeEdDSAPrivateKey(w, priv)
|
|
default:
|
|
err = errors.InvalidArgumentError("unknown private key type")
|
|
}
|
|
|
|
return err
|
|
}
|
|
|
|
func serializeRSAPrivateKey(w io.Writer, priv *rsa.PrivateKey) error {
|
|
err := writeBig(w, priv.D)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
err = writeBig(w, priv.Primes[1])
|
|
if err != nil {
|
|
return err
|
|
}
|
|
err = writeBig(w, priv.Primes[0])
|
|
if err != nil {
|
|
return err
|
|
}
|
|
return writeBig(w, priv.Precomputed.Qinv)
|
|
}
|
|
|
|
func serializeDSAPrivateKey(w io.Writer, priv *dsa.PrivateKey) error {
|
|
return writeBig(w, priv.X)
|
|
}
|
|
|
|
func serializeElGamalPrivateKey(w io.Writer, priv *elgamal.PrivateKey) error {
|
|
return writeBig(w, priv.X)
|
|
}
|
|
|
|
func serializeECDSAPrivateKey(w io.Writer, priv *ecdsa.PrivateKey) error {
|
|
return writeBig(w, priv.D)
|
|
}
|
|
|
|
func serializeECDHPrivateKey(w io.Writer, priv *ecdh.PrivateKey) error {
|
|
return writeBig(w, priv.X)
|
|
}
|
|
|
|
func serializeEdDSAPrivateKey(w io.Writer, priv *EdDSAPrivateKey) error {
|
|
return writeMPI(w, priv.seed.bitLength, priv.seed.bytes)
|
|
}
|
|
|
|
// Decrypt decrypts an encrypted private key using a passphrase.
|
|
func (pk *PrivateKey) Decrypt(passphrase []byte) error {
|
|
if !pk.Encrypted {
|
|
return nil
|
|
}
|
|
// For GNU Dummy S2K, there's no key here, so don't do anything.
|
|
if pk.s2k == nil {
|
|
return nil
|
|
}
|
|
|
|
key := make([]byte, pk.cipher.KeySize())
|
|
pk.s2k(key, passphrase)
|
|
block := pk.cipher.new(key)
|
|
cfb := cipher.NewCFBDecrypter(block, pk.iv)
|
|
|
|
data := make([]byte, len(pk.encryptedData))
|
|
cfb.XORKeyStream(data, pk.encryptedData)
|
|
|
|
if pk.sha1Checksum {
|
|
if len(data) < sha1.Size {
|
|
return errors.StructuralError("truncated private key data")
|
|
}
|
|
h := sha1.New()
|
|
h.Write(data[:len(data)-sha1.Size])
|
|
sum := h.Sum(nil)
|
|
if !bytes.Equal(sum, data[len(data)-sha1.Size:]) {
|
|
return errors.StructuralError("private key checksum failure")
|
|
}
|
|
data = data[:len(data)-sha1.Size]
|
|
} else {
|
|
if len(data) < 2 {
|
|
return errors.StructuralError("truncated private key data")
|
|
}
|
|
var sum uint16
|
|
for i := 0; i < len(data)-2; i++ {
|
|
sum += uint16(data[i])
|
|
}
|
|
if data[len(data)-2] != uint8(sum>>8) ||
|
|
data[len(data)-1] != uint8(sum) {
|
|
return errors.StructuralError("private key checksum failure")
|
|
}
|
|
data = data[:len(data)-2]
|
|
}
|
|
|
|
return pk.parsePrivateKey(data)
|
|
}
|
|
|
|
func (pk *PrivateKey) parsePrivateKey(data []byte) (err error) {
|
|
switch pk.PublicKey.PubKeyAlgo {
|
|
case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly, PubKeyAlgoRSAEncryptOnly:
|
|
return pk.parseRSAPrivateKey(data)
|
|
case PubKeyAlgoDSA:
|
|
return pk.parseDSAPrivateKey(data)
|
|
case PubKeyAlgoElGamal:
|
|
return pk.parseElGamalPrivateKey(data)
|
|
case PubKeyAlgoECDSA:
|
|
return pk.parseECDSAPrivateKey(data)
|
|
case PubKeyAlgoECDH:
|
|
return pk.parseECDHPrivateKey(data)
|
|
case PubKeyAlgoEdDSA:
|
|
return pk.parseEdDSAPrivateKey(data)
|
|
case PubKeyAlgoBadElGamal:
|
|
return errors.UnsupportedError("parsing el-gamal sign-or-encrypt privatekeys is unsupported")
|
|
default:
|
|
return errors.UnsupportedError("cannot parse this private key type")
|
|
}
|
|
}
|
|
|
|
func (pk *PrivateKey) parseRSAPrivateKey(data []byte) (err error) {
|
|
rsaPub := pk.PublicKey.PublicKey.(*rsa.PublicKey)
|
|
rsaPriv := new(rsa.PrivateKey)
|
|
rsaPriv.PublicKey = *rsaPub
|
|
|
|
buf := bytes.NewBuffer(data)
|
|
d, _, err := readMPI(buf)
|
|
if err != nil {
|
|
return
|
|
}
|
|
p, _, err := readMPI(buf)
|
|
if err != nil {
|
|
return
|
|
}
|
|
q, _, err := readMPI(buf)
|
|
if err != nil {
|
|
return
|
|
}
|
|
|
|
rsaPriv.D = new(big.Int).SetBytes(d)
|
|
rsaPriv.Primes = make([]*big.Int, 2)
|
|
rsaPriv.Primes[0] = new(big.Int).SetBytes(p)
|
|
rsaPriv.Primes[1] = new(big.Int).SetBytes(q)
|
|
if err := rsaPriv.Validate(); err != nil {
|
|
return err
|
|
}
|
|
rsaPriv.Precompute()
|
|
pk.PrivateKey = rsaPriv
|
|
pk.Encrypted = false
|
|
pk.encryptedData = nil
|
|
|
|
return nil
|
|
}
|
|
|
|
func (pk *PrivateKey) parseDSAPrivateKey(data []byte) (err error) {
|
|
dsaPub := pk.PublicKey.PublicKey.(*dsa.PublicKey)
|
|
dsaPriv := new(dsa.PrivateKey)
|
|
dsaPriv.PublicKey = *dsaPub
|
|
|
|
buf := bytes.NewBuffer(data)
|
|
x, _, err := readMPI(buf)
|
|
if err != nil {
|
|
return
|
|
}
|
|
|
|
dsaPriv.X = new(big.Int).SetBytes(x)
|
|
pk.PrivateKey = dsaPriv
|
|
pk.Encrypted = false
|
|
pk.encryptedData = nil
|
|
|
|
return nil
|
|
}
|
|
|
|
func (pk *PrivateKey) parseElGamalPrivateKey(data []byte) (err error) {
|
|
pub := pk.PublicKey.PublicKey.(*elgamal.PublicKey)
|
|
priv := new(elgamal.PrivateKey)
|
|
priv.PublicKey = *pub
|
|
|
|
buf := bytes.NewBuffer(data)
|
|
x, _, err := readMPI(buf)
|
|
if err != nil {
|
|
return
|
|
}
|
|
|
|
priv.X = new(big.Int).SetBytes(x)
|
|
pk.PrivateKey = priv
|
|
pk.Encrypted = false
|
|
pk.encryptedData = nil
|
|
|
|
return nil
|
|
}
|
|
|
|
func (pk *PrivateKey) parseECDHPrivateKey(data []byte) (err error) {
|
|
pub := pk.PublicKey.PublicKey.(*ecdh.PublicKey)
|
|
priv := new(ecdh.PrivateKey)
|
|
priv.PublicKey = *pub
|
|
|
|
buf := bytes.NewBuffer(data)
|
|
d, _, err := readMPI(buf)
|
|
if err != nil {
|
|
return
|
|
}
|
|
|
|
priv.X = new(big.Int).SetBytes(d)
|
|
pk.PrivateKey = priv
|
|
pk.Encrypted = false
|
|
pk.encryptedData = nil
|
|
return nil
|
|
}
|
|
|
|
func (pk *PrivateKey) parseECDSAPrivateKey(data []byte) (err error) {
|
|
ecdsaPub := pk.PublicKey.PublicKey.(*ecdsa.PublicKey)
|
|
ecdsaPriv := new(ecdsa.PrivateKey)
|
|
ecdsaPriv.PublicKey = *ecdsaPub
|
|
|
|
buf := bytes.NewBuffer(data)
|
|
d, _, err := readMPI(buf)
|
|
if err != nil {
|
|
return
|
|
}
|
|
|
|
ecdsaPriv.D = new(big.Int).SetBytes(d)
|
|
pk.PrivateKey = ecdsaPriv
|
|
pk.Encrypted = false
|
|
pk.encryptedData = nil
|
|
|
|
return nil
|
|
}
|
|
|
|
func (pk *PrivateKey) parseEdDSAPrivateKey(data []byte) (err error) {
|
|
eddsaPriv := new(EdDSAPrivateKey)
|
|
eddsaPriv.PublicKey = pk.PublicKey
|
|
|
|
buf := bytes.NewBuffer(data)
|
|
eddsaPriv.seed.bytes, eddsaPriv.seed.bitLength, err = readMPI(buf)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if bLen := len(eddsaPriv.seed.bytes); bLen != 32 { // 32 bytes private part of ed25519 key.
|
|
return errors.UnsupportedError(fmt.Sprintf("Unexpected EdDSA private key length: %d", bLen))
|
|
}
|
|
|
|
pk.PrivateKey = eddsaPriv
|
|
pk.Encrypted = false
|
|
pk.encryptedData = nil
|
|
|
|
return nil
|
|
}
|