diff options
Diffstat (limited to 'vendor/github.com/docker/libtrust/util.go')
-rw-r--r-- | vendor/github.com/docker/libtrust/util.go | 363 |
1 files changed, 363 insertions, 0 deletions
diff --git a/vendor/github.com/docker/libtrust/util.go b/vendor/github.com/docker/libtrust/util.go new file mode 100644 index 000000000..a5a101d3f --- /dev/null +++ b/vendor/github.com/docker/libtrust/util.go @@ -0,0 +1,363 @@ +package libtrust + +import ( + "bytes" + "crypto" + "crypto/elliptic" + "crypto/tls" + "crypto/x509" + "encoding/base32" + "encoding/base64" + "encoding/binary" + "encoding/pem" + "errors" + "fmt" + "math/big" + "net/url" + "os" + "path/filepath" + "strings" + "time" +) + +// LoadOrCreateTrustKey will load a PrivateKey from the specified path +func LoadOrCreateTrustKey(trustKeyPath string) (PrivateKey, error) { + if err := os.MkdirAll(filepath.Dir(trustKeyPath), 0700); err != nil { + return nil, err + } + + trustKey, err := LoadKeyFile(trustKeyPath) + if err == ErrKeyFileDoesNotExist { + trustKey, err = GenerateECP256PrivateKey() + if err != nil { + return nil, fmt.Errorf("error generating key: %s", err) + } + + if err := SaveKey(trustKeyPath, trustKey); err != nil { + return nil, fmt.Errorf("error saving key file: %s", err) + } + + dir, file := filepath.Split(trustKeyPath) + if err := SavePublicKey(filepath.Join(dir, "public-"+file), trustKey.PublicKey()); err != nil { + return nil, fmt.Errorf("error saving public key file: %s", err) + } + } else if err != nil { + return nil, fmt.Errorf("error loading key file: %s", err) + } + return trustKey, nil +} + +// NewIdentityAuthTLSClientConfig returns a tls.Config configured to use identity +// based authentication from the specified dockerUrl, the rootConfigPath and +// the server name to which it is connecting. +// If trustUnknownHosts is true it will automatically add the host to the +// known-hosts.json in rootConfigPath. +func NewIdentityAuthTLSClientConfig(dockerUrl string, trustUnknownHosts bool, rootConfigPath string, serverName string) (*tls.Config, error) { + tlsConfig := newTLSConfig() + + trustKeyPath := filepath.Join(rootConfigPath, "key.json") + knownHostsPath := filepath.Join(rootConfigPath, "known-hosts.json") + + u, err := url.Parse(dockerUrl) + if err != nil { + return nil, fmt.Errorf("unable to parse machine url") + } + + if u.Scheme == "unix" { + return nil, nil + } + + addr := u.Host + proto := "tcp" + + trustKey, err := LoadOrCreateTrustKey(trustKeyPath) + if err != nil { + return nil, fmt.Errorf("unable to load trust key: %s", err) + } + + knownHosts, err := LoadKeySetFile(knownHostsPath) + if err != nil { + return nil, fmt.Errorf("could not load trusted hosts file: %s", err) + } + + allowedHosts, err := FilterByHosts(knownHosts, addr, false) + if err != nil { + return nil, fmt.Errorf("error filtering hosts: %s", err) + } + + certPool, err := GenerateCACertPool(trustKey, allowedHosts) + if err != nil { + return nil, fmt.Errorf("Could not create CA pool: %s", err) + } + + tlsConfig.ServerName = serverName + tlsConfig.RootCAs = certPool + + x509Cert, err := GenerateSelfSignedClientCert(trustKey) + if err != nil { + return nil, fmt.Errorf("certificate generation error: %s", err) + } + + tlsConfig.Certificates = []tls.Certificate{{ + Certificate: [][]byte{x509Cert.Raw}, + PrivateKey: trustKey.CryptoPrivateKey(), + Leaf: x509Cert, + }} + + tlsConfig.InsecureSkipVerify = true + + testConn, err := tls.Dial(proto, addr, tlsConfig) + if err != nil { + return nil, fmt.Errorf("tls Handshake error: %s", err) + } + + opts := x509.VerifyOptions{ + Roots: tlsConfig.RootCAs, + CurrentTime: time.Now(), + DNSName: tlsConfig.ServerName, + Intermediates: x509.NewCertPool(), + } + + certs := testConn.ConnectionState().PeerCertificates + for i, cert := range certs { + if i == 0 { + continue + } + opts.Intermediates.AddCert(cert) + } + + if _, err := certs[0].Verify(opts); err != nil { + if _, ok := err.(x509.UnknownAuthorityError); ok { + if trustUnknownHosts { + pubKey, err := FromCryptoPublicKey(certs[0].PublicKey) + if err != nil { + return nil, fmt.Errorf("error extracting public key from cert: %s", err) + } + + pubKey.AddExtendedField("hosts", []string{addr}) + + if err := AddKeySetFile(knownHostsPath, pubKey); err != nil { + return nil, fmt.Errorf("error adding machine to known hosts: %s", err) + } + } else { + return nil, fmt.Errorf("unable to connect. unknown host: %s", addr) + } + } + } + + testConn.Close() + tlsConfig.InsecureSkipVerify = false + + return tlsConfig, nil +} + +// joseBase64UrlEncode encodes the given data using the standard base64 url +// encoding format but with all trailing '=' characters omitted in accordance +// with the jose specification. +// http://tools.ietf.org/html/draft-ietf-jose-json-web-signature-31#section-2 +func joseBase64UrlEncode(b []byte) string { + return strings.TrimRight(base64.URLEncoding.EncodeToString(b), "=") +} + +// joseBase64UrlDecode decodes the given string using the standard base64 url +// decoder but first adds the appropriate number of trailing '=' characters in +// accordance with the jose specification. +// http://tools.ietf.org/html/draft-ietf-jose-json-web-signature-31#section-2 +func joseBase64UrlDecode(s string) ([]byte, error) { + s = strings.Replace(s, "\n", "", -1) + s = strings.Replace(s, " ", "", -1) + switch len(s) % 4 { + case 0: + case 2: + s += "==" + case 3: + s += "=" + default: + return nil, errors.New("illegal base64url string") + } + return base64.URLEncoding.DecodeString(s) +} + +func keyIDEncode(b []byte) string { + s := strings.TrimRight(base32.StdEncoding.EncodeToString(b), "=") + var buf bytes.Buffer + var i int + for i = 0; i < len(s)/4-1; i++ { + start := i * 4 + end := start + 4 + buf.WriteString(s[start:end] + ":") + } + buf.WriteString(s[i*4:]) + return buf.String() +} + +func keyIDFromCryptoKey(pubKey PublicKey) string { + // Generate and return a 'libtrust' fingerprint of the public key. + // For an RSA key this should be: + // SHA256(DER encoded ASN1) + // Then truncated to 240 bits and encoded into 12 base32 groups like so: + // ABCD:EFGH:IJKL:MNOP:QRST:UVWX:YZ23:4567:ABCD:EFGH:IJKL:MNOP + derBytes, err := x509.MarshalPKIXPublicKey(pubKey.CryptoPublicKey()) + if err != nil { + return "" + } + hasher := crypto.SHA256.New() + hasher.Write(derBytes) + return keyIDEncode(hasher.Sum(nil)[:30]) +} + +func stringFromMap(m map[string]interface{}, key string) (string, error) { + val, ok := m[key] + if !ok { + return "", fmt.Errorf("%q value not specified", key) + } + + str, ok := val.(string) + if !ok { + return "", fmt.Errorf("%q value must be a string", key) + } + delete(m, key) + + return str, nil +} + +func parseECCoordinate(cB64Url string, curve elliptic.Curve) (*big.Int, error) { + curveByteLen := (curve.Params().BitSize + 7) >> 3 + + cBytes, err := joseBase64UrlDecode(cB64Url) + if err != nil { + return nil, fmt.Errorf("invalid base64 URL encoding: %s", err) + } + cByteLength := len(cBytes) + if cByteLength != curveByteLen { + return nil, fmt.Errorf("invalid number of octets: got %d, should be %d", cByteLength, curveByteLen) + } + return new(big.Int).SetBytes(cBytes), nil +} + +func parseECPrivateParam(dB64Url string, curve elliptic.Curve) (*big.Int, error) { + dBytes, err := joseBase64UrlDecode(dB64Url) + if err != nil { + return nil, fmt.Errorf("invalid base64 URL encoding: %s", err) + } + + // The length of this octet string MUST be ceiling(log-base-2(n)/8) + // octets (where n is the order of the curve). This is because the private + // key d must be in the interval [1, n-1] so the bitlength of d should be + // no larger than the bitlength of n-1. The easiest way to find the octet + // length is to take bitlength(n-1), add 7 to force a carry, and shift this + // bit sequence right by 3, which is essentially dividing by 8 and adding + // 1 if there is any remainder. Thus, the private key value d should be + // output to (bitlength(n-1)+7)>>3 octets. + n := curve.Params().N + octetLength := (new(big.Int).Sub(n, big.NewInt(1)).BitLen() + 7) >> 3 + dByteLength := len(dBytes) + + if dByteLength != octetLength { + return nil, fmt.Errorf("invalid number of octets: got %d, should be %d", dByteLength, octetLength) + } + + return new(big.Int).SetBytes(dBytes), nil +} + +func parseRSAModulusParam(nB64Url string) (*big.Int, error) { + nBytes, err := joseBase64UrlDecode(nB64Url) + if err != nil { + return nil, fmt.Errorf("invalid base64 URL encoding: %s", err) + } + + return new(big.Int).SetBytes(nBytes), nil +} + +func serializeRSAPublicExponentParam(e int) []byte { + // We MUST use the minimum number of octets to represent E. + // E is supposed to be 65537 for performance and security reasons + // and is what golang's rsa package generates, but it might be + // different if imported from some other generator. + buf := make([]byte, 4) + binary.BigEndian.PutUint32(buf, uint32(e)) + var i int + for i = 0; i < 8; i++ { + if buf[i] != 0 { + break + } + } + return buf[i:] +} + +func parseRSAPublicExponentParam(eB64Url string) (int, error) { + eBytes, err := joseBase64UrlDecode(eB64Url) + if err != nil { + return 0, fmt.Errorf("invalid base64 URL encoding: %s", err) + } + // Only the minimum number of bytes were used to represent E, but + // binary.BigEndian.Uint32 expects at least 4 bytes, so we need + // to add zero padding if necassary. + byteLen := len(eBytes) + buf := make([]byte, 4-byteLen, 4) + eBytes = append(buf, eBytes...) + + return int(binary.BigEndian.Uint32(eBytes)), nil +} + +func parseRSAPrivateKeyParamFromMap(m map[string]interface{}, key string) (*big.Int, error) { + b64Url, err := stringFromMap(m, key) + if err != nil { + return nil, err + } + + paramBytes, err := joseBase64UrlDecode(b64Url) + if err != nil { + return nil, fmt.Errorf("invaled base64 URL encoding: %s", err) + } + + return new(big.Int).SetBytes(paramBytes), nil +} + +func createPemBlock(name string, derBytes []byte, headers map[string]interface{}) (*pem.Block, error) { + pemBlock := &pem.Block{Type: name, Bytes: derBytes, Headers: map[string]string{}} + for k, v := range headers { + switch val := v.(type) { + case string: + pemBlock.Headers[k] = val + case []string: + if k == "hosts" { + pemBlock.Headers[k] = strings.Join(val, ",") + } else { + // Return error, non-encodable type + } + default: + // Return error, non-encodable type + } + } + + return pemBlock, nil +} + +func pubKeyFromPEMBlock(pemBlock *pem.Block) (PublicKey, error) { + cryptoPublicKey, err := x509.ParsePKIXPublicKey(pemBlock.Bytes) + if err != nil { + return nil, fmt.Errorf("unable to decode Public Key PEM data: %s", err) + } + + pubKey, err := FromCryptoPublicKey(cryptoPublicKey) + if err != nil { + return nil, err + } + + addPEMHeadersToKey(pemBlock, pubKey) + + return pubKey, nil +} + +func addPEMHeadersToKey(pemBlock *pem.Block, pubKey PublicKey) { + for key, value := range pemBlock.Headers { + var safeVal interface{} + if key == "hosts" { + safeVal = strings.Split(value, ",") + } else { + safeVal = value + } + pubKey.AddExtendedField(key, safeVal) + } +} |