1 files changed, 155 insertions, 0 deletions
diff --git a/modules/caddypki/crypto.go b/modules/caddypki/crypto.go
new file mode 100644
index 0000000..e701c40
--- /dev/null
+++ b/modules/caddypki/crypto.go
@@ -0,0 +1,155 @@
+// Copyright 2015 Matthew Holt and The Caddy Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package caddypki
+
+import (
+	"bytes"
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/ed25519"
+	"crypto/rsa"
+	"crypto/x509"
+	"encoding/pem"
+	"fmt"
+	"io/ioutil"
+	"strings"
+)
+
+func pemDecodeSingleCert(pemDER []byte) (*x509.Certificate, error) {
+	pemBlock, remaining := pem.Decode(pemDER)
+	if pemBlock == nil {
+		return nil, fmt.Errorf("no PEM block found")
+	}
+	if len(remaining) > 0 {
+		return nil, fmt.Errorf("input contained more than a single PEM block")
+	}
+	if pemBlock.Type != "CERTIFICATE" {
+		return nil, fmt.Errorf("expected PEM block type to be CERTIFICATE, but got '%s'", pemBlock.Type)
+	}
+	return x509.ParseCertificate(pemBlock.Bytes)
+}
+
+func pemEncodeCert(der []byte) ([]byte, error) {
+	return pemEncode("CERTIFICATE", der)
+}
+
+// pemEncodePrivateKey marshals a EC or RSA private key into a PEM-encoded array of bytes.
+// TODO: this is the same thing as in certmagic. Should we reuse that code somehow? It's unexported.
+func pemEncodePrivateKey(key crypto.PrivateKey) ([]byte, error) {
+	var pemType string
+	var keyBytes []byte
+	switch key := key.(type) {
+	case *ecdsa.PrivateKey:
+		var err error
+		pemType = "EC"
+		keyBytes, err = x509.MarshalECPrivateKey(key)
+		if err != nil {
+			return nil, err
+		}
+	case *rsa.PrivateKey:
+		pemType = "RSA"
+		keyBytes = x509.MarshalPKCS1PrivateKey(key)
+	case *ed25519.PrivateKey:
+		var err error
+		pemType = "ED25519"
+		keyBytes, err = x509.MarshalPKCS8PrivateKey(key)
+		if err != nil {
+			return nil, err
+		}
+	default:
+		return nil, fmt.Errorf("unsupported key type: %T", key)
+	}
+	return pemEncode(pemType+" PRIVATE KEY", keyBytes)
+}
+
+// pemDecodePrivateKey loads a PEM-encoded ECC/RSA private key from an array of bytes.
+// Borrowed from Go standard library, to handle various private key and PEM block types.
+// https://github.com/golang/go/blob/693748e9fa385f1e2c3b91ca9acbb6c0ad2d133d/src/crypto/tls/tls.go#L291-L308
+// https://github.com/golang/go/blob/693748e9fa385f1e2c3b91ca9acbb6c0ad2d133d/src/crypto/tls/tls.go#L238)
+// TODO: this is the same thing as in certmagic. Should we reuse that code somehow? It's unexported.
+func pemDecodePrivateKey(keyPEMBytes []byte) (crypto.PrivateKey, error) {
+	keyBlockDER, _ := pem.Decode(keyPEMBytes)
+
+	if keyBlockDER.Type != "PRIVATE KEY" && !strings.HasSuffix(keyBlockDER.Type, " PRIVATE KEY") {
+		return nil, fmt.Errorf("unknown PEM header %q", keyBlockDER.Type)
+	}
+
+	if key, err := x509.ParsePKCS1PrivateKey(keyBlockDER.Bytes); err == nil {
+		return key, nil
+	}
+
+	if key, err := x509.ParsePKCS8PrivateKey(keyBlockDER.Bytes); err == nil {
+		switch key := key.(type) {
+		case *rsa.PrivateKey, *ecdsa.PrivateKey, ed25519.PrivateKey:
+			return key, nil
+		default:
+			return nil, fmt.Errorf("found unknown private key type in PKCS#8 wrapping: %T", key)
+		}
+	}
+
+	if key, err := x509.ParseECPrivateKey(keyBlockDER.Bytes); err == nil {
+		return key, nil
+	}
+
+	return nil, fmt.Errorf("unknown private key type")
+}
+
+func pemEncode(blockType string, b []byte) ([]byte, error) {
+	var buf bytes.Buffer
+	err := pem.Encode(&buf, &pem.Block{Type: blockType, Bytes: b})
+	return buf.Bytes(), err
+}
+
+func trusted(cert *x509.Certificate) bool {
+	chains, err := cert.Verify(x509.VerifyOptions{})
+	return len(chains) > 0 && err == nil
+}
+
+// KeyPair represents a public-private key pair, where the
+// public key is also called a certificate.
+type KeyPair struct {
+	Certificate string `json:"certificate,omitempty"`
+	PrivateKey  string `json:"private_key,omitempty"`
+	Format      string `json:"format,omitempty"`
+}
+
+// Load loads the certificate and key.
+func (kp KeyPair) Load() (*x509.Certificate, interface{}, error) {
+	switch kp.Format {
+	case "", "pem_file":
+		certData, err := ioutil.ReadFile(kp.Certificate)
+		if err != nil {
+			return nil, nil, err
+		}
+		keyData, err := ioutil.ReadFile(kp.PrivateKey)
+		if err != nil {
+			return nil, nil, err
+		}
+
+		cert, err := pemDecodeSingleCert(certData)
+		if err != nil {
+			return nil, nil, err
+		}
+		key, err := pemDecodePrivateKey(keyData)
+		if err != nil {
+			return nil, nil, err
+		}
+
+		return cert, key, nil
+
+	default:
+		return nil, nil, fmt.Errorf("unsupported format: %s", kp.Format)
+	}
+}