Adding upstream version 0.0~git20230121.c1716e8.upstream/0.0_git20230121.c1716e8upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 363 insertions, 0 deletions

diff --git a/util.go b/util.go
new file mode 100644
index 0000000..a5a101d
--- /dev/null
+++ b/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)
+	}
+}