OP#792 initial commit after fork

internal/config/certs.go

@@ -0,0 +1,114 @@
+// Copyright (c) 2015-2021 MinIO, Inc.
+//
+// This file is part of MinIO Object Storage stack
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package config
+
+import (
+	"bytes"
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/pem"
+	"errors"
+	"os"
+
+	"github.com/minio/pkg/v3/env"
+)
+
+// EnvCertPassword is the environment variable which contains the password used
+// to decrypt the TLS private key. It must be set if the TLS private key is
+// password protected.
+const EnvCertPassword = "MINIO_CERT_PASSWD"
+
+// ParsePublicCertFile - parses public cert into its *x509.Certificate equivalent.
+func ParsePublicCertFile(certFile string) (x509Certs []*x509.Certificate, err error) {
+	// Read certificate file.
+	var data []byte
+	if data, err = os.ReadFile(certFile); err != nil {
+		return nil, err
+	}
+
+	// Trimming leading and tailing white spaces.
+	data = bytes.TrimSpace(data)
+
+	// Parse all certs in the chain.
+	current := data
+	for len(current) > 0 {
+		var pemBlock *pem.Block
+		if pemBlock, current = pem.Decode(current); pemBlock == nil {
+			return nil, ErrTLSUnexpectedData(nil).Msgf("Could not read PEM block from file %s", certFile)
+		}
+
+		var x509Cert *x509.Certificate
+		if x509Cert, err = x509.ParseCertificate(pemBlock.Bytes); err != nil {
+			return nil, ErrTLSUnexpectedData(nil).Msgf("Failed to parse `%s`: %s", certFile, err.Error())
+		}
+
+		x509Certs = append(x509Certs, x509Cert)
+	}
+
+	if len(x509Certs) == 0 {
+		return nil, ErrTLSUnexpectedData(nil).Msgf("Empty public certificate file %s", certFile)
+	}
+
+	return x509Certs, nil
+}
+
+// LoadX509KeyPair - load an X509 key pair (private key , certificate)
+// from the provided paths. The private key may be encrypted and is
+// decrypted using the ENV_VAR: MINIO_CERT_PASSWD.
+func LoadX509KeyPair(certFile, keyFile string) (tls.Certificate, error) {
+	certPEMBlock, err := os.ReadFile(certFile)
+	if err != nil {
+		return tls.Certificate{}, ErrTLSReadError(nil).Msgf("Unable to read the public key: %s", err)
+	}
+	keyPEMBlock, err := os.ReadFile(keyFile)
+	if err != nil {
+		return tls.Certificate{}, ErrTLSReadError(nil).Msgf("Unable to read the private key: %s", err)
+	}
+	key, rest := pem.Decode(keyPEMBlock)
+	if len(rest) > 0 {
+		return tls.Certificate{}, ErrTLSUnexpectedData(nil).Msgf("The private key contains additional data")
+	}
+	if key == nil {
+		return tls.Certificate{}, ErrTLSUnexpectedData(nil).Msgf("The private key is not readable")
+	}
+	if x509.IsEncryptedPEMBlock(key) {
+		password := env.Get(EnvCertPassword, "")
+		if len(password) == 0 {
+			return tls.Certificate{}, ErrTLSNoPassword(nil)
+		}
+		decryptedKey, decErr := x509.DecryptPEMBlock(key, []byte(password))
+		if decErr != nil {
+			return tls.Certificate{}, ErrTLSWrongPassword(decErr)
+		}
+		keyPEMBlock = pem.EncodeToMemory(&pem.Block{Type: key.Type, Bytes: decryptedKey})
+	}
+	cert, err := tls.X509KeyPair(certPEMBlock, keyPEMBlock)
+	if err != nil {
+		return tls.Certificate{}, ErrTLSUnexpectedData(nil).Msg(err.Error())
+	}
+	return cert, nil
+}
+
+// EnsureCertAndKey checks if both client certificate and key paths are provided
+func EnsureCertAndKey(clientCert, clientKey string) error {
+	if (clientCert != "" && clientKey == "") ||
+		(clientCert == "" && clientKey != "") {
+		return errors.New("cert and key must be specified as a pair")
+	}
+	return nil
+}