gitee.com/lh-her-team/common@v1.5.1/crypto/tls/credentials/credentials.go

// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package credentials

import (
	"errors"
	"fmt"
	"io/ioutil"
	"net"
	"strings"

	cmtls "gitee.com/lh-her-team/common/crypto/tls"
	cmx509 "gitee.com/lh-her-team/common/crypto/x509"
	"golang.org/x/net/context"
	"google.golang.org/grpc/credentials"
)

var (
	// alpnProtoStr are the specified application level protocols for gRPC.
	alpnProtoStr = []string{"h2"}
)

// PerRPCCredentials defines the common interface for the credentials which need to
// attach security information to every RPC (e.g., oauth2).
type PerRPCCredentials interface {
	// GetRequestMetadata gets the current request metadata, refreshing
	// tokens if required. This should be called by the transport layer on
	// each request, and the data should be populated in headers or other
	// context. uri is the URI of the entry point for the request. When
	// supported by the underlying implementation, ctx can be used for
	// timeout and cancellation.
	// TODO(zhaoq): Define the set of the qualified keys instead of leaving
	// it as an arbitrary string.
	GetRequestMetadata(ctx context.Context, uri ...string) (map[string]string, error)
	// RequireTransportSecurity indicates whether the credentials requires
	// transport security.
	RequireTransportSecurity() bool
}

// ProtocolInfo provides information regarding the gRPC wire protocol version,
// security protocol, security protocol version in use, server name, etc.
type ProtocolInfo struct {
	// ProtocolVersion is the gRPC wire protocol version.
	ProtocolVersion string
	// SecurityProtocol is the security protocol in use.
	SecurityProtocol string
	// SecurityVersion is the security protocol version.
	SecurityVersion string
	// ServerName is the user-configured server name.
	ServerName string
}

// AuthInfo defines the common interface for the auth information the users are interested in.
type AuthInfo interface {
	AuthType() string
}

var (
	// ErrConnDispatched indicates that rawConn has been dispatched out of gRPC
	// and the caller should not close rawConn.
	ErrConnDispatched = errors.New("credentials: rawConn is dispatched out of gRPC")
)

// TLSInfo contains the auth information for a TLS authenticated connection.
// It implements the AuthInfo interface.
type TLSInfo struct {
	State cmtls.ConnectionState
}

// AuthType returns the type of TLSInfo as a string.
func (t TLSInfo) AuthType() string {
	return "tls"
}

// tlsCreds is the credentials required for authenticating a connection using TLS.
type tlsCreds struct {
	// TLS configuration
	config *cmtls.Config
}

func (c tlsCreds) Info() credentials.ProtocolInfo {
	return credentials.ProtocolInfo{
		SecurityProtocol: "tls",
		SecurityVersion:  "1.2",
		ServerName:       c.config.ServerName,
	}
}

func (c *tlsCreds) ClientHandshake(ctx context.Context, addr string, rawConn net.Conn) (_ net.Conn, _ credentials.AuthInfo, err error) {
	// use local cfg to avoid clobbering ServerName if using multiple endpoints
	cfg := cloneTLSConfig(c.config)
	if cfg.ServerName == "" {
		colonPos := strings.LastIndex(addr, ":")
		if colonPos == -1 {
			colonPos = len(addr)
		}
		cfg.ServerName = addr[:colonPos]
	}
	conn := cmtls.Client(rawConn, cfg)
	errChannel := make(chan error, 1)
	go func() {
		errChannel <- conn.Handshake()
	}()
	select {
	case err := <-errChannel:
		if err != nil {
			return nil, nil, err
		}
	case <-ctx.Done():
		return nil, nil, ctx.Err()
	}
	return conn, TLSInfo{conn.ConnectionState()}, nil
}

func (c *tlsCreds) ServerHandshake(rawConn net.Conn) (net.Conn, credentials.AuthInfo, error) {
	conn := cmtls.Server(rawConn, c.config)
	if err := conn.Handshake(); err != nil {
		return nil, nil, err
	}
	return conn, TLSInfo{conn.ConnectionState()}, nil
}

func (c *tlsCreds) Clone() credentials.TransportCredentials {
	return NewTLS(c.config)
}

func (c *tlsCreds) OverrideServerName(serverNameOverride string) error {
	c.config.ServerName = serverNameOverride
	return nil
}

// NewTLS uses c to construct a TransportCredentials based on TLS.
func NewTLS(c *cmtls.Config) credentials.TransportCredentials {
	tc := &tlsCreds{cloneTLSConfig(c)}
	tc.config.NextProtos = alpnProtoStr
	return tc
}

// NewClientTLSFromCert constructs TLS credentials from the input certificate for client.
// serverNameOverride is for testing only. If set to a non empty string,
// it will override the virtual host name of authority (e.g. :authority header field) in requests.
func NewClientTLSFromCert(cp *cmx509.CertPool, serverNameOverride string) credentials.TransportCredentials {
	return NewTLS(&cmtls.Config{ServerName: serverNameOverride, RootCAs: cp})
}

// NewClientTLSFromFile constructs TLS credentials from the input certificate file for client.
// serverNameOverride is for testing only. If set to a non empty string,
// it will override the virtual host name of authority (e.g. :authority header field) in requests.
func NewClientTLSFromFile(certFile, serverNameOverride string) (credentials.TransportCredentials, error) {
	b, err := ioutil.ReadFile(certFile)
	if err != nil {
		return nil, err
	}
	cp := cmx509.NewCertPool()
	if !cp.AppendCertsFromPEM(b) {
		return nil, fmt.Errorf("credentials: failed to append certificates")
	}
	return NewTLS(&cmtls.Config{ServerName: serverNameOverride, RootCAs: cp}), nil
}

// NewServerTLSFromCert constructs TLS credentials from the input certificate for server.
func NewServerTLSFromCert(cert *cmtls.Certificate) credentials.TransportCredentials {
	return NewTLS(&cmtls.Config{Certificates: []cmtls.Certificate{*cert}})
}

// NewServerTLSFromFile constructs TLS credentials from the input certificate file and key
// file for server.
func NewServerTLSFromFile(certFile, keyFile string) (credentials.TransportCredentials, error) {
	cert, err := cmtls.LoadX509KeyPair(certFile, keyFile)
	if err != nil {
		return nil, err
	}
	return NewTLS(&cmtls.Config{Certificates: []cmtls.Certificate{cert}}), nil
}