mirror of
https://github.com/VictoriaMetrics/VictoriaMetrics.git
synced 2024-12-16 00:41:24 +01:00
283 lines
10 KiB
Go
283 lines
10 KiB
Go
// Copyright 2020 Google LLC.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
// cba.go (certificate-based access) contains utils for implementing Device Certificate
|
|
// Authentication according to https://google.aip.dev/auth/4114 and Default Credentials
|
|
// for Google Cloud Virtual Environments according to https://google.aip.dev/auth/4115.
|
|
//
|
|
// The overall logic for DCA is as follows:
|
|
// 1. If both endpoint override and client certificate are specified, use them as is.
|
|
// 2. If user does not specify client certificate, we will attempt to use default
|
|
// client certificate.
|
|
// 3. If user does not specify endpoint override, we will use defaultMtlsEndpoint if
|
|
// client certificate is available and defaultEndpoint otherwise.
|
|
//
|
|
// Implications of the above logic:
|
|
// 1. If the user specifies a non-mTLS endpoint override but client certificate is
|
|
// available, we will pass along the cert anyway and let the server decide what to do.
|
|
// 2. If the user specifies an mTLS endpoint override but client certificate is not
|
|
// available, we will not fail-fast, but let backend throw error when connecting.
|
|
//
|
|
// If running within Google's cloud environment, and client certificate is not specified
|
|
// and not available through DCA, we will try mTLS with credentials held by
|
|
// the Secure Session Agent, which is part of Google's cloud infrastructure.
|
|
//
|
|
// We would like to avoid introducing client-side logic that parses whether the
|
|
// endpoint override is an mTLS url, since the url pattern may change at anytime.
|
|
//
|
|
// This package is not intended for use by end developers. Use the
|
|
// google.golang.org/api/option package to configure API clients.
|
|
|
|
// Package internal supports the options and transport packages.
|
|
package internal
|
|
|
|
import (
|
|
"context"
|
|
"crypto/tls"
|
|
"net"
|
|
"net/url"
|
|
"os"
|
|
"strings"
|
|
|
|
"github.com/google/s2a-go"
|
|
"github.com/google/s2a-go/fallback"
|
|
"google.golang.org/api/internal/cert"
|
|
"google.golang.org/grpc/credentials"
|
|
)
|
|
|
|
const (
|
|
mTLSModeAlways = "always"
|
|
mTLSModeNever = "never"
|
|
mTLSModeAuto = "auto"
|
|
|
|
// Experimental: if true, the code will try MTLS with S2A as the default for transport security. Default value is false.
|
|
googleAPIUseS2AEnv = "EXPERIMENTAL_GOOGLE_API_USE_S2A"
|
|
)
|
|
|
|
// getClientCertificateSourceAndEndpoint is a convenience function that invokes
|
|
// getClientCertificateSource and getEndpoint sequentially and returns the client
|
|
// cert source and endpoint as a tuple.
|
|
func getClientCertificateSourceAndEndpoint(settings *DialSettings) (cert.Source, string, error) {
|
|
clientCertSource, err := getClientCertificateSource(settings)
|
|
if err != nil {
|
|
return nil, "", err
|
|
}
|
|
endpoint, err := getEndpoint(settings, clientCertSource)
|
|
if err != nil {
|
|
return nil, "", err
|
|
}
|
|
return clientCertSource, endpoint, nil
|
|
}
|
|
|
|
type transportConfig struct {
|
|
clientCertSource cert.Source // The client certificate source.
|
|
endpoint string // The corresponding endpoint to use based on client certificate source.
|
|
s2aAddress string // The S2A address if it can be used, otherwise an empty string.
|
|
s2aMTLSEndpoint string // The MTLS endpoint to use with S2A.
|
|
}
|
|
|
|
func getTransportConfig(settings *DialSettings) (*transportConfig, error) {
|
|
clientCertSource, endpoint, err := getClientCertificateSourceAndEndpoint(settings)
|
|
if err != nil {
|
|
return &transportConfig{
|
|
clientCertSource: nil, endpoint: "", s2aAddress: "", s2aMTLSEndpoint: "",
|
|
}, err
|
|
}
|
|
defaultTransportConfig := transportConfig{
|
|
clientCertSource: clientCertSource,
|
|
endpoint: endpoint,
|
|
s2aAddress: "",
|
|
s2aMTLSEndpoint: "",
|
|
}
|
|
|
|
// Check the env to determine whether to use S2A.
|
|
if !isGoogleS2AEnabled() {
|
|
return &defaultTransportConfig, nil
|
|
}
|
|
|
|
// If client cert is found, use that over S2A.
|
|
// If MTLS is not enabled for the endpoint, skip S2A.
|
|
if clientCertSource != nil || !mtlsEndpointEnabledForS2A() {
|
|
return &defaultTransportConfig, nil
|
|
}
|
|
s2aMTLSEndpoint := settings.DefaultMTLSEndpoint
|
|
// If there is endpoint override, honor it.
|
|
if settings.Endpoint != "" {
|
|
s2aMTLSEndpoint = endpoint
|
|
}
|
|
s2aAddress := GetS2AAddress()
|
|
if s2aAddress == "" {
|
|
return &defaultTransportConfig, nil
|
|
}
|
|
return &transportConfig{
|
|
clientCertSource: clientCertSource,
|
|
endpoint: endpoint,
|
|
s2aAddress: s2aAddress,
|
|
s2aMTLSEndpoint: s2aMTLSEndpoint,
|
|
}, nil
|
|
}
|
|
|
|
func isGoogleS2AEnabled() bool {
|
|
return strings.ToLower(os.Getenv(googleAPIUseS2AEnv)) == "true"
|
|
}
|
|
|
|
// getClientCertificateSource returns a default client certificate source, if
|
|
// not provided by the user.
|
|
//
|
|
// A nil default source can be returned if the source does not exist. Any exceptions
|
|
// encountered while initializing the default source will be reported as client
|
|
// error (ex. corrupt metadata file).
|
|
//
|
|
// Important Note: For now, the environment variable GOOGLE_API_USE_CLIENT_CERTIFICATE
|
|
// must be set to "true" to allow certificate to be used (including user provided
|
|
// certificates). For details, see AIP-4114.
|
|
func getClientCertificateSource(settings *DialSettings) (cert.Source, error) {
|
|
if !isClientCertificateEnabled() {
|
|
return nil, nil
|
|
} else if settings.ClientCertSource != nil {
|
|
return settings.ClientCertSource, nil
|
|
} else {
|
|
return cert.DefaultSource()
|
|
}
|
|
}
|
|
|
|
func isClientCertificateEnabled() bool {
|
|
useClientCert := os.Getenv("GOOGLE_API_USE_CLIENT_CERTIFICATE")
|
|
// TODO(andyrzhao): Update default to return "true" after DCA feature is fully released.
|
|
return strings.ToLower(useClientCert) == "true"
|
|
}
|
|
|
|
// getEndpoint returns the endpoint for the service, taking into account the
|
|
// user-provided endpoint override "settings.Endpoint".
|
|
//
|
|
// If no endpoint override is specified, we will either return the default endpoint or
|
|
// the default mTLS endpoint if a client certificate is available.
|
|
//
|
|
// You can override the default endpoint choice (mtls vs. regular) by setting the
|
|
// GOOGLE_API_USE_MTLS_ENDPOINT environment variable.
|
|
//
|
|
// If the endpoint override is an address (host:port) rather than full base
|
|
// URL (ex. https://...), then the user-provided address will be merged into
|
|
// the default endpoint. For example, WithEndpoint("myhost:8000") and
|
|
// WithDefaultEndpoint("https://foo.com/bar/baz") will return "https://myhost:8080/bar/baz"
|
|
func getEndpoint(settings *DialSettings, clientCertSource cert.Source) (string, error) {
|
|
if settings.Endpoint == "" {
|
|
mtlsMode := getMTLSMode()
|
|
if mtlsMode == mTLSModeAlways || (clientCertSource != nil && mtlsMode == mTLSModeAuto) {
|
|
return settings.DefaultMTLSEndpoint, nil
|
|
}
|
|
return settings.DefaultEndpoint, nil
|
|
}
|
|
if strings.Contains(settings.Endpoint, "://") {
|
|
// User passed in a full URL path, use it verbatim.
|
|
return settings.Endpoint, nil
|
|
}
|
|
if settings.DefaultEndpoint == "" {
|
|
// If DefaultEndpoint is not configured, use the user provided endpoint verbatim.
|
|
// This allows a naked "host[:port]" URL to be used with GRPC Direct Path.
|
|
return settings.Endpoint, nil
|
|
}
|
|
|
|
// Assume user-provided endpoint is host[:port], merge it with the default endpoint.
|
|
return mergeEndpoints(settings.DefaultEndpoint, settings.Endpoint)
|
|
}
|
|
|
|
func getMTLSMode() string {
|
|
mode := os.Getenv("GOOGLE_API_USE_MTLS_ENDPOINT")
|
|
if mode == "" {
|
|
mode = os.Getenv("GOOGLE_API_USE_MTLS") // Deprecated.
|
|
}
|
|
if mode == "" {
|
|
return mTLSModeAuto
|
|
}
|
|
return strings.ToLower(mode)
|
|
}
|
|
|
|
func mergeEndpoints(baseURL, newHost string) (string, error) {
|
|
u, err := url.Parse(fixScheme(baseURL))
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
return strings.Replace(baseURL, u.Host, newHost, 1), nil
|
|
}
|
|
|
|
func fixScheme(baseURL string) string {
|
|
if !strings.Contains(baseURL, "://") {
|
|
return "https://" + baseURL
|
|
}
|
|
return baseURL
|
|
}
|
|
|
|
// GetGRPCTransportConfigAndEndpoint returns an instance of credentials.TransportCredentials, and the
|
|
// corresponding endpoint to use for GRPC client.
|
|
func GetGRPCTransportConfigAndEndpoint(settings *DialSettings) (credentials.TransportCredentials, string, error) {
|
|
config, err := getTransportConfig(settings)
|
|
if err != nil {
|
|
return nil, "", err
|
|
}
|
|
|
|
defaultTransportCreds := credentials.NewTLS(&tls.Config{
|
|
GetClientCertificate: config.clientCertSource,
|
|
})
|
|
if config.s2aAddress == "" {
|
|
return defaultTransportCreds, config.endpoint, nil
|
|
}
|
|
|
|
var fallbackOpts *s2a.FallbackOptions
|
|
// In case of S2A failure, fall back to the endpoint that would've been used without S2A.
|
|
if fallbackHandshake, err := fallback.DefaultFallbackClientHandshakeFunc(config.endpoint); err == nil {
|
|
fallbackOpts = &s2a.FallbackOptions{
|
|
FallbackClientHandshakeFunc: fallbackHandshake,
|
|
}
|
|
}
|
|
|
|
s2aTransportCreds, err := s2a.NewClientCreds(&s2a.ClientOptions{
|
|
S2AAddress: config.s2aAddress,
|
|
FallbackOpts: fallbackOpts,
|
|
})
|
|
if err != nil {
|
|
// Use default if we cannot initialize S2A client transport credentials.
|
|
return defaultTransportCreds, config.endpoint, nil
|
|
}
|
|
return s2aTransportCreds, config.s2aMTLSEndpoint, nil
|
|
}
|
|
|
|
// GetHTTPTransportConfigAndEndpoint returns a client certificate source, a function for dialing MTLS with S2A,
|
|
// and the endpoint to use for HTTP client.
|
|
func GetHTTPTransportConfigAndEndpoint(settings *DialSettings) (cert.Source, func(context.Context, string, string) (net.Conn, error), string, error) {
|
|
config, err := getTransportConfig(settings)
|
|
if err != nil {
|
|
return nil, nil, "", err
|
|
}
|
|
|
|
if config.s2aAddress == "" {
|
|
return config.clientCertSource, nil, config.endpoint, nil
|
|
}
|
|
|
|
var fallbackOpts *s2a.FallbackOptions
|
|
// In case of S2A failure, fall back to the endpoint that would've been used without S2A.
|
|
if fallbackURL, err := url.Parse(config.endpoint); err == nil {
|
|
if fallbackDialer, fallbackServerAddr, err := fallback.DefaultFallbackDialerAndAddress(fallbackURL.Hostname()); err == nil {
|
|
fallbackOpts = &s2a.FallbackOptions{
|
|
FallbackDialer: &s2a.FallbackDialer{
|
|
Dialer: fallbackDialer,
|
|
ServerAddr: fallbackServerAddr,
|
|
},
|
|
}
|
|
}
|
|
}
|
|
|
|
dialTLSContextFunc := s2a.NewS2ADialTLSContextFunc(&s2a.ClientOptions{
|
|
S2AAddress: config.s2aAddress,
|
|
FallbackOpts: fallbackOpts,
|
|
})
|
|
return nil, dialTLSContextFunc, config.s2aMTLSEndpoint, nil
|
|
}
|
|
|
|
// mtlsEndpointEnabledForS2A checks if the endpoint is indeed MTLS-enabled, so that we can use S2A for MTLS connection.
|
|
var mtlsEndpointEnabledForS2A = func() bool {
|
|
// TODO(xmenxk): determine this via discovery config.
|
|
return true
|
|
}
|