Move etcd, logger, crypto into their own packages (#8366)

- Deprecates _MINIO_PROFILER, `mc admin profile` does the job
- Move ENVs to common location in cmd/config/

cmd/config/certs.go

@@ -0,0 +1,150 @@
+/*
+ * MinIO Cloud Storage, (C) 2015, 2016, 2017 MinIO, Inc.
+ *
+ * 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 config
+
+import (
+	"bytes"
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/pem"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+
+	"github.com/minio/minio/pkg/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 = ioutil.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, ErrSSLUnexpectedData(nil).Msg("Could not read PEM block from file %s", certFile)
+		}
+
+		var x509Cert *x509.Certificate
+		if x509Cert, err = x509.ParseCertificate(pemBlock.Bytes); err != nil {
+			return nil, ErrSSLUnexpectedData(err)
+		}
+
+		x509Certs = append(x509Certs, x509Cert)
+	}
+
+	if len(x509Certs) == 0 {
+		return nil, ErrSSLUnexpectedData(nil).Msg("Empty public certificate file %s", certFile)
+	}
+
+	return x509Certs, nil
+}
+
+// GetRootCAs - returns all the root CAs into certPool
+// at the input certsCADir
+func GetRootCAs(certsCAsDir string) (*x509.CertPool, error) {
+	rootCAs, _ := x509.SystemCertPool()
+	if rootCAs == nil {
+		// In some systems (like Windows) system cert pool is
+		// not supported or no certificates are present on the
+		// system - so we create a new cert pool.
+		rootCAs = x509.NewCertPool()
+	}
+
+	fis, err := ioutil.ReadDir(certsCAsDir)
+	if err != nil {
+		if os.IsNotExist(err) {
+			err = nil // Return success if CA's directory is missing.
+		}
+		return rootCAs, err
+	}
+
+	// Load all custom CA files.
+	for _, fi := range fis {
+		// Only load regular files as public cert.
+		if fi.Mode().IsRegular() {
+			caCert, err := ioutil.ReadFile(filepath.Join(certsCAsDir, fi.Name()))
+			if err != nil {
+				return rootCAs, err
+			}
+			rootCAs.AppendCertsFromPEM(caCert)
+		}
+	}
+	return rootCAs, 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 := ioutil.ReadFile(certFile)
+	if err != nil {
+		return tls.Certificate{}, ErrSSLUnexpectedError(err)
+	}
+	keyPEMBlock, err := ioutil.ReadFile(keyFile)
+	if err != nil {
+		return tls.Certificate{}, ErrSSLUnexpectedError(err)
+	}
+	key, rest := pem.Decode(keyPEMBlock)
+	if len(rest) > 0 {
+		return tls.Certificate{}, ErrSSLUnexpectedData(nil).Msg("The private key contains additional data")
+	}
+	if x509.IsEncryptedPEMBlock(key) {
+		password, ok := env.Lookup(EnvCertPassword)
+		if !ok {
+			return tls.Certificate{}, ErrSSLNoPassword(nil)
+		}
+		decryptedKey, decErr := x509.DecryptPEMBlock(key, []byte(password))
+		if decErr != nil {
+			return tls.Certificate{}, ErrSSLWrongPassword(decErr)
+		}
+		keyPEMBlock = pem.EncodeToMemory(&pem.Block{Type: key.Type, Bytes: decryptedKey})
+	}
+	cert, err := tls.X509KeyPair(certPEMBlock, keyPEMBlock)
+	if err != nil {
+		return tls.Certificate{}, ErrSSLUnexpectedData(nil).Msg(err.Error())
+	}
+	// Ensure that the private key is not a P-384 or P-521 EC key.
+	// The Go TLS stack does not provide constant-time implementations of P-384 and P-521.
+	if priv, ok := cert.PrivateKey.(crypto.Signer); ok {
+		if pub, ok := priv.Public().(*ecdsa.PublicKey); ok {
+			switch pub.Params().Name {
+			case "P-384":
+				fallthrough
+			case "P-521":
+				// unfortunately there is no cleaner way to check
+				return tls.Certificate{}, ErrSSLUnexpectedData(nil).Msg("tls: the ECDSA curve '%s' is not supported", pub.Params().Name)
+			}
+		}
+	}
+	return cert, nil
+}