Add support for mTLS for Audit log target (#11645)

cmd/config-current.go

@@ -553,7 +553,7 @@ If you need help to migrate smoothly visit: https://min.io/pricing`
 					http.WithAuthToken(l.AuthToken),
 					http.WithUserAgent(loggerUserAgent),
 					http.WithLogKind(string(logger.All)),
-					http.WithTransport(NewGatewayHTTPTransport()),
+					http.WithTransport(NewGatewayHTTPTransportWithClientCerts(l.ClientCert, l.ClientKey)),
 				),
 			); err != nil {
 				logger.LogIf(ctx, fmt.Errorf("Unable to initialize audit HTTP target: %w", err))

cmd/config/certs.go

@@ -23,6 +23,7 @@ import (
 	"crypto/tls"
 	"crypto/x509"
 	"encoding/pem"
+	"errors"
 	"io/ioutil"
 
 	"github.com/minio/minio/pkg/env"
@@ -113,3 +114,12 @@ func LoadX509KeyPair(certFile, keyFile string) (tls.Certificate, 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
+}

cmd/logger/config.go

@@ -33,6 +33,8 @@ type HTTP struct {
 	Enabled    bool   `json:"enabled"`
 	Endpoint   string `json:"endpoint"`
 	AuthToken  string `json:"authToken"`
+	ClientCert string `json:"clientCert"`
+	ClientKey  string `json:"clientKey"`
 }
 
 // Config console and http logger targets
@@ -46,6 +48,8 @@ type Config struct {
 const (
 	Endpoint   = "endpoint"
 	AuthToken  = "auth_token"
+	ClientCert = "client_cert"
+	ClientKey  = "client_key"
 
 	EnvLoggerWebhookEnable    = "MINIO_LOGGER_WEBHOOK_ENABLE"
 	EnvLoggerWebhookEndpoint  = "MINIO_LOGGER_WEBHOOK_ENDPOINT"
@@ -54,6 +58,8 @@ const (
 	EnvAuditWebhookEnable     = "MINIO_AUDIT_WEBHOOK_ENABLE"
 	EnvAuditWebhookEndpoint   = "MINIO_AUDIT_WEBHOOK_ENDPOINT"
 	EnvAuditWebhookAuthToken  = "MINIO_AUDIT_WEBHOOK_AUTH_TOKEN"
+	EnvAuditWebhookClientCert = "MINIO_AUDIT_WEBHOOK_CLIENT_CERT"
+	EnvAuditWebhookClientKey  = "MINIO_AUDIT_WEBHOOK_CLIENT_KEY"
 )
 
 // Default KVS for loggerHTTP and loggerAuditHTTP
@@ -85,6 +91,14 @@ var (
 			Key:   AuthToken,
 			Value: "",
 		},
+		config.KV{
+			Key:   ClientCert,
+			Value: "",
+		},
+		config.KV{
+			Key:   ClientKey,
+			Value: "",
+		},
 	}
 )
 
@@ -251,10 +265,24 @@ func LookupConfig(scfg config.Config) (Config, error) {
 		if target != config.Default {
 			authTokenEnv = EnvAuditWebhookAuthToken + config.Default + target
 		}
+		clientCertEnv := EnvAuditWebhookClientCert
+		if target != config.Default {
+			clientCertEnv = EnvAuditWebhookClientCert + config.Default + target
+		}
+		clientKeyEnv := EnvAuditWebhookClientKey
+		if target != config.Default {
+			clientKeyEnv = EnvAuditWebhookClientKey + config.Default + target
+		}
+		err = config.EnsureCertAndKey(env.Get(clientCertEnv, ""), env.Get(clientKeyEnv, ""))
+		if err != nil {
+			return cfg, err
+		}
 		cfg.Audit[target] = HTTP{
 			Enabled:    true,
 			Endpoint:   env.Get(endpointEnv, ""),
 			AuthToken:  env.Get(authTokenEnv, ""),
+			ClientCert: env.Get(clientCertEnv, ""),
+			ClientKey:  env.Get(clientKeyEnv, ""),
 		}
 	}
 
@@ -307,10 +335,16 @@ func LookupConfig(scfg config.Config) (Config, error) {
 		if !enabled {
 			continue
 		}
+		err = config.EnsureCertAndKey(kv.Get(ClientCert), kv.Get(ClientKey))
+		if err != nil {
+			return cfg, err
+		}
 		cfg.Audit[starget] = HTTP{
 			Enabled:    true,
 			Endpoint:   kv.Get(Endpoint),
 			AuthToken:  kv.Get(AuthToken),
+			ClientCert: kv.Get(ClientCert),
+			ClientKey:  kv.Get(ClientKey),
 		}
 	}
 

cmd/logger/help.go

@@ -16,7 +16,9 @@
 
 package logger
 
-import "github.com/minio/minio/cmd/config"
+import (
+	"github.com/minio/minio/cmd/config"
+)
 
 // Help template for logger http and audit
 var (
@@ -58,5 +60,17 @@ var (
 			Optional:    true,
 			Type:        "sentence",
 		},
+		config.HelpKV{
+			Key:         ClientCert,
+			Description: "mTLS certificate for Audit Webhook authentication",
+			Optional:    true,
+			Type:        "string",
+		},
+		config.HelpKV{
+			Key:         ClientKey,
+			Description: "mTLS certificate key for Audit Webhook authentication",
+			Optional:    true,
+			Type:        "string",
+		},
 	}
 )

cmd/utils.go

@@ -43,6 +43,7 @@ import (
 	"github.com/gorilla/mux"
 	xhttp "github.com/minio/minio/cmd/http"
 	"github.com/minio/minio/cmd/logger"
+	"github.com/minio/minio/pkg/certs"
 	"github.com/minio/minio/pkg/handlers"
 	"github.com/minio/minio/pkg/madmin"
 	"golang.org/x/net/http2"
@@ -606,6 +607,25 @@ func newCustomHTTPTransport(tlsConfig *tls.Config, dialTimeout time.Duration) fu
 	}
 }
 
+// NewGatewayHTTPTransportWithClientCerts returns a new http configuration
+// used while communicating with the cloud backends.
+func NewGatewayHTTPTransportWithClientCerts(clientCert, clientKey string) *http.Transport {
+	transport := newGatewayHTTPTransport(1 * time.Minute)
+	if clientCert != "" && clientKey != "" {
+		ctx, cancel := context.WithTimeout(context.Background(), time.Second)
+		defer cancel()
+		c, err := certs.NewManager(ctx, clientCert, clientKey, tls.LoadX509KeyPair)
+		if err != nil {
+			logger.LogIf(ctx, fmt.Errorf("failed to load client key and cert, please check your endpoint configuration: %s",
+				err.Error()))
+		}
+		if c != nil {
+			transport.TLSClientConfig.GetClientCertificate = c.GetClientCertificate
+		}
+	}
+	return transport
+}
+
 // NewGatewayHTTPTransport returns a new http configuration
 // used while communicating with the cloud backends.
 func NewGatewayHTTPTransport() *http.Transport {

docs/logging/README.md

@@ -38,7 +38,7 @@ minio server /mnt/data
 Assuming `mc` is already [configured](https://docs.min.io/docs/minio-client-quickstart-guide.html)
 ```
 mc admin config get myminio/ audit_webhook
-audit_webhook:name1 auth_token="" endpoint=""
+audit_webhook:name1 enable=off endpoint= auth_token= client_cert= client_key= 
 ```
 
 ```
@@ -53,6 +53,8 @@ MinIO also honors environment variable for HTTP target Audit logging as shown be
 export MINIO_AUDIT_WEBHOOK_ENABLE_target1="on"
 export MINIO_AUDIT_WEBHOOK_AUTH_TOKEN_target1="token"
 export MINIO_AUDIT_WEBHOOK_ENDPOINT_target1=http://localhost:8080/minio/logs
+export MINIO_AUDIT_WEBHOOK_CLIENT_CERT="/tmp/cert.pem"
+export MINIO_AUDIT_WEBHOOK_CLIENT_KEY=="/tmp/key.pem"
 minio server /mnt/data
 ```