kafka sasl-mechanism auth support for SCRAM-SHA-256, SCRAM-SHA-512, G…

…SSAPI (influxdata#8318)

docs/LICENSE_OF_DEPENDENCIES.md

@@ -141,6 +141,8 @@ following works:
 - github.com/wavefronthq/wavefront-sdk-go [Apache License 2.0](https://github.com/wavefrontHQ/wavefront-sdk-go/blob/master/LICENSE)
 - github.com/wvanbergen/kafka [MIT License](https://github.com/wvanbergen/kafka/blob/master/LICENSE)
 - github.com/wvanbergen/kazoo-go [MIT License](https://github.com/wvanbergen/kazoo-go/blob/master/MIT-LICENSE)
+- github.com/xdg/scram [Apache License 2.0](https://github.com/xdg-go/scram/blob/master/LICENSE)
+- github.com/xdg/stringprep [Apache License 2.0](https://github.com/xdg-go/stringprep/blob/master/LICENSE)
 - github.com/yuin/gopher-lua [MIT License](https://github.com/yuin/gopher-lua/blob/master/LICENSE)
 - go.opencensus.io [Apache License 2.0](https://github.com/census-instrumentation/opencensus-go/blob/master/LICENSE)
 - go.starlark.net [BSD 3-Clause "New" or "Revised" License](https://github.com/google/starlark-go/blob/master/LICENSE)

go.mod

@@ -127,6 +127,7 @@ require (
 	github.com/wavefronthq/wavefront-sdk-go v0.9.2
 	github.com/wvanbergen/kafka v0.0.0-20171203153745-e2edea948ddf
 	github.com/wvanbergen/kazoo-go v0.0.0-20180202103751-f72d8611297a // indirect
+	github.com/xdg/scram v0.0.0-20180814205039-7eeb5667e42c
 	github.com/yuin/gopher-lua v0.0.0-20180630135845-46796da1b0b4 // indirect
 	go.starlark.net v0.0.0-20200901195727-6e684ef5eeee
 	golang.org/x/exp v0.0.0-20200224162631-6cc2880d07d6 // indirect

go.sum

@@ -592,7 +592,9 @@ github.com/wvanbergen/kafka v0.0.0-20171203153745-e2edea948ddf h1:TOV5PC6fIWwFOF
 github.com/wvanbergen/kafka v0.0.0-20171203153745-e2edea948ddf/go.mod h1:nxx7XRXbR9ykhnC8lXqQyJS0rfvJGxKyKw/sT1YOttg=
 github.com/wvanbergen/kazoo-go v0.0.0-20180202103751-f72d8611297a h1:ILoU84rj4AQ3q6cjQvtb9jBjx4xzR/Riq/zYhmDQiOk=
 github.com/wvanbergen/kazoo-go v0.0.0-20180202103751-f72d8611297a/go.mod h1:vQQATAGxVK20DC1rRubTJbZDDhhpA4QfU02pMdPxGO4=
+github.com/xdg/scram v0.0.0-20180814205039-7eeb5667e42c h1:u40Z8hqBAAQyv+vATcGgV0YCnDjqSL7/q/JyPhhJSPk=
 github.com/xdg/scram v0.0.0-20180814205039-7eeb5667e42c/go.mod h1:lB8K/P019DLNhemzwFU4jHLhdvlE6uDZjXFejJXr49I=
+github.com/xdg/stringprep v1.0.0 h1:d9X0esnoa3dFsV0FG35rAT0RIhYFlPq7MiP+DW89La0=
 github.com/xdg/stringprep v1.0.0/go.mod h1:Jhud4/sHMO4oL310DaZAKk9ZaJ08SJfe+sJh0HrGL1Y=
 github.com/yuin/goldmark v1.1.25/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/gopher-lua v0.0.0-20180630135845-46796da1b0b4 h1:f6CCNiTjQZ0uWK4jPwhwYB8QIGGfn0ssD9kVzRUUUpk=

plugins/common/kafka/sasl.go

@@ -6,6 +6,78 @@ import (
 	"github.com/Shopify/sarama"
 )
 
+type SASLAuth struct {
+	SASLUsername  string `toml:"sasl_username"`
+	SASLPassword  string `toml:"sasl_password"`
+	SASLMechanism string `toml:"sasl_mechanism"`
+	SASLVersion   *int   `toml:"sasl_version"`
+
+	// GSSAPI config
+	SASLGSSAPIServiceName        string `toml:"sasl_gssapi_service_name"`
+	SASLGSSAPIAuthType           string `toml:"sasl_gssapi_auth_type"`
+	SASLGSSAPIDisablePAFXFAST    bool   `toml:"sasl_gssapi_disable_pafxfast"`
+	SASLGSSAPIKerberosConfigPath string `toml:"sasl_gssapi_kerberos_config_path"`
+	SASLGSSAPIKeyTabPath         string `toml:"sasl_gssapi_key_tab_path"`
+	SASLGSSAPIRealm              string `toml:"sasl_gssapi_realm"`
+
+	// OAUTHBEARER config. experimental. undoubtedly this is not good enough.
+	SASLAccessToken string `toml:"sasl_access_token"`
+}
+
+// SetSASLConfig configures SASL for kafka (sarama)
+func (k *SASLAuth) SetSASLConfig(config *sarama.Config) error {
+	config.Net.SASL.User = k.SASLUsername
+	config.Net.SASL.Password = k.SASLPassword
+
+	if k.SASLMechanism != "" {
+		config.Net.SASL.Mechanism = sarama.SASLMechanism(k.SASLMechanism)
+		switch config.Net.SASL.Mechanism {
+		case sarama.SASLTypeSCRAMSHA256:
+			config.Net.SASL.SCRAMClientGeneratorFunc = func() sarama.SCRAMClient {
+				return &XDGSCRAMClient{HashGeneratorFcn: SHA256}
+			}
+		case sarama.SASLTypeSCRAMSHA512:
+			config.Net.SASL.SCRAMClientGeneratorFunc = func() sarama.SCRAMClient {
+				return &XDGSCRAMClient{HashGeneratorFcn: SHA512}
+			}
+		case sarama.SASLTypeOAuth:
+			config.Net.SASL.TokenProvider = k // use self as token provider.
+		case sarama.SASLTypeGSSAPI:
+			config.Net.SASL.GSSAPI.ServiceName = k.SASLGSSAPIServiceName
+			config.Net.SASL.GSSAPI.AuthType = gssapiAuthType(k.SASLGSSAPIAuthType)
+			config.Net.SASL.GSSAPI.Username = k.SASLUsername
+			config.Net.SASL.GSSAPI.Password = k.SASLPassword
+			config.Net.SASL.GSSAPI.DisablePAFXFAST = k.SASLGSSAPIDisablePAFXFAST
+			config.Net.SASL.GSSAPI.KerberosConfigPath = k.SASLGSSAPIKerberosConfigPath
+			config.Net.SASL.GSSAPI.KeyTabPath = k.SASLGSSAPIKeyTabPath
+			config.Net.SASL.GSSAPI.Realm = k.SASLGSSAPIRealm
+
+		case sarama.SASLTypePlaintext:
+			// nothing.
+		default:
+		}
+	}
+
+	if k.SASLUsername != "" || k.SASLMechanism != "" {
+		config.Net.SASL.Enable = true
+
+		version, err := SASLVersion(config.Version, k.SASLVersion)
+		if err != nil {
+			return err
+		}
+		config.Net.SASL.Version = version
+	}
+	return nil
+}
+
+// Token does nothing smart, it just grabs a hard-coded token from config.
+func (k *SASLAuth) Token() (*sarama.AccessToken, error) {
+	return &sarama.AccessToken{
+		Token:      k.SASLAccessToken,
+		Extensions: map[string]string{},
+	}, nil
+}
+
 func SASLVersion(kafkaVersion sarama.KafkaVersion, saslVersion *int) (int16, error) {
 	if saslVersion == nil {
 		if kafkaVersion.IsAtLeast(sarama.V1_0_0_0) {
@@ -23,3 +95,15 @@ func SASLVersion(kafkaVersion sarama.KafkaVersion, saslVersion *int) (int16, err
 		return 0, errors.New("invalid SASL version")
 	}
 }
+
+func gssapiAuthType(authType string) int {
+	switch authType {
+	case "KRB5_USER_AUTH":
+		return sarama.KRB5_USER_AUTH
+	case "KRB5_KEYTAB_AUTH":
+		return sarama.KRB5_KEYTAB_AUTH
+	default:
+		return 0
+	}
+
+}

plugins/common/kafka/scram_client.go

@@ -0,0 +1,36 @@
+package kafka
+
+import (
+	"crypto/sha256"
+	"crypto/sha512"
+	"hash"
+
+	"github.com/xdg/scram"
+)
+
+var SHA256 scram.HashGeneratorFcn = func() hash.Hash { return sha256.New() }
+var SHA512 scram.HashGeneratorFcn = func() hash.Hash { return sha512.New() }
+
+type XDGSCRAMClient struct {
+	*scram.Client
+	*scram.ClientConversation
+	scram.HashGeneratorFcn
+}
+
+func (x *XDGSCRAMClient) Begin(userName, password, authzID string) (err error) {
+	x.Client, err = x.HashGeneratorFcn.NewClient(userName, password, authzID)
+	if err != nil {
+		return err
+	}
+	x.ClientConversation = x.Client.NewConversation()
+	return nil
+}
+
+func (x *XDGSCRAMClient) Step(challenge string) (response string, err error) {
+	response, err = x.ClientConversation.Step(challenge)
+	return
+}
+
+func (x *XDGSCRAMClient) Done() bool {
+	return x.ClientConversation.Done()
+}

plugins/inputs/kafka_consumer/README.md

@@ -39,6 +39,23 @@ and use the old zookeeper connection method.
   # sasl_username = "kafka"
   # sasl_password = "secret"
 
+  ## Optional SASL:
+  ## one of: OAUTHBEARER, PLAIN, SCRAM-SHA-256, SCRAM-SHA-512, GSSAPI
+  ## (defaults to PLAIN)
+  # sasl_mechanism = ""
+
+  ## used if sasl_mechanism is GSSAPI (experimental)
+  # sasl_gssapi_service_name = ""
+  # ## One of: KRB5_USER_AUTH and KRB5_KEYTAB_AUTH
+  # sasl_gssapi_auth_type = "KRB5_USER_AUTH"
+  # sasl_gssapi_kerberos_config_path = "/"
+  # sasl_gssapi_realm = "realm"
+  # sasl_gssapi_key_tab_path = ""
+  # sasl_gssapi_disable_pafxfast = false
+
+  ## used if sasl_mechanism is OAUTHBEARER (experimental)
+  # sasl_access_token = ""
+
   ## SASL protocol version.  When connecting to Azure EventHub set to 0.
   # sasl_version = 1
 

plugins/inputs/kafka_consumer/kafka_consumer.go

@@ -48,6 +48,23 @@ const sampleConfig = `
   # sasl_username = "kafka"
   # sasl_password = "secret"
 
+  ## Optional SASL:
+  ## one of: OAUTHBEARER, PLAIN, SCRAM-SHA-256, SCRAM-SHA-512, GSSAPI
+  ## (defaults to PLAIN)
+  # sasl_mechanism = ""
+
+  ## used if sasl_mechanism is GSSAPI (experimental)
+  # sasl_gssapi_service_name = ""
+  # ## One of: KRB5_USER_AUTH and KRB5_KEYTAB_AUTH
+  # sasl_gssapi_auth_type = "KRB5_USER_AUTH"
+  # sasl_gssapi_kerberos_config_path = "/"
+  # sasl_gssapi_realm = "realm"
+  # sasl_gssapi_key_tab_path = ""
+  # sasl_gssapi_disable_pafxfast = false
+
+  ## used if sasl_mechanism is OAUTHBEARER (experimental)
+  # sasl_access_token = ""
+
   ## SASL protocol version.  When connecting to Azure EventHub set to 0.
   # sasl_version = 1
 
@@ -102,9 +119,8 @@ type KafkaConsumer struct {
 	Topics                 []string `toml:"topics"`
 	TopicTag               string   `toml:"topic_tag"`
 	Version                string   `toml:"version"`
-	SASLPassword           string   `toml:"sasl_password"`
-	SASLUsername           string   `toml:"sasl_username"`
-	SASLVersion            *int     `toml:"sasl_version"`
+
+	kafka.SASLAuth
 
 	EnableTLS *bool `toml:"enable_tls"`
 	tls.ClientConfig
@@ -191,16 +207,8 @@ func (k *KafkaConsumer) Init() error {
 		}
 	}
 
-	if k.SASLUsername != "" && k.SASLPassword != "" {
-		config.Net.SASL.User = k.SASLUsername
-		config.Net.SASL.Password = k.SASLPassword
-		config.Net.SASL.Enable = true
-
-		version, err := kafka.SASLVersion(config.Version, k.SASLVersion)
-		if err != nil {
-			return err
-		}
-		config.Net.SASL.Version = version
+	if err := k.SetSASLConfig(config); err != nil {
+		return err
 	}
 
 	if k.ClientID != "" {

plugins/outputs/kafka/README.md

@@ -111,6 +111,23 @@ This plugin writes to a [Kafka Broker](http://kafka.apache.org/07/quickstart.htm
   # sasl_username = "kafka"
   # sasl_password = "secret"
 
+  ## Optional SASL:
+  ## one of: OAUTHBEARER, PLAIN, SCRAM-SHA-256, SCRAM-SHA-512, GSSAPI
+  ## (defaults to PLAIN)
+  # sasl_mechanism = ""
+
+  ## used if sasl_mechanism is GSSAPI (experimental)
+  # sasl_gssapi_service_name = ""
+  # ## One of: KRB5_USER_AUTH and KRB5_KEYTAB_AUTH
+  # sasl_gssapi_auth_type = "KRB5_USER_AUTH"
+  # sasl_gssapi_kerberos_config_path = "/"
+  # sasl_gssapi_realm = "realm"
+  # sasl_gssapi_key_tab_path = ""
+  # sasl_gssapi_disable_pafxfast = false
+
+  ## used if sasl_mechanism is OAUTHBEARER (experimental)
+  # sasl_access_token = ""
+
   ## SASL protocol version.  When connecting to Azure EventHub set to 0.
   # sasl_version = 1