Authentication

The Java driver supports all MongoDB authentication mechanisms, including those only available in the MongoDB Enterprise Edition.

MongoCredential

import com.mongodb.MongoCredential;
import com.mongodb.ConnectionString;
import com.mongodb.reactivestreams.client.MongoClients;
import com.mongodb.reactivestreams.client.MongoClient;

An authentication credential is represented as an instance of the MongoCredential class. The MongoCredential class includes static factory methods for each of the supported authentication mechanisms.

Default Authentication Mechanism

In MongoDB 3.0, MongoDB changed the default authentication mechanism from MONGODB-CR to SCRAM-SHA-1. In MongoDB 4.0 support for the deprecated MONGODB-CR mechanism was removed and SCRAM-SHA-256 support was added.

To create a credential that will authenticate using the default authentication mechanism regardless of server version, create a credential using the createCredential static factory method:

String user;     // the user name
String source;   // the source where the user is defined
char[] password; // the password as a character array
// ...
MongoCredential credential = MongoCredential.createCredential(user, source, password);

MongoClient mongoClient = MongoClients.create(
        MongoClientSettings.builder()
                .applyToClusterSettings(builder -> 
                        builder.hosts(Arrays.asList(new ServerAddress("host1", 27017))))
                .credential(credential)
                .build());

Or use a connection string without explicitly specifying the authentication mechanism:

MongoClient mongoClient = MongoClients.create("mongodb://user1:pwd1@host1/?authSource=db1");

For challenge and response mechanisms, using the default authentication mechanism is the recommended approach as it will make upgrading from MongoDB 2.6 to MongoDB 3.0 seamless, even after upgrading the authentication schema. For MongoDB 4.0 users it is also recommended as the supported authentication mechanisms are checked and the correct hashing algorithm is used.

SCRAM

Salted Challenge Response Authentication Mechanism (SCRAM) has been the default authentication mechanism for MongoDB since 3.0. SCRAM is based on the IETF RFC 5802 standard that defines best practices for implementation of challenge-response mechanisms for authenticating users with passwords.

MongoDB 3.0 introduced support for SCRAM-SHA-1 which uses the SHA-1 hashing function. MongoDB 4.0 introduced support for SCRAM-SHA-256 which uses the SHA-256 hashing function.

SCRAM-SHA-256

Requires MongoDB 4.0 and featureCompatibilityVersion to be set to 4.0.

To explicitly create a credential of type SCRAM-SHA-256, use the createScramSha256Credential method:

String user;     // the user name
String source;   // the source where the user is defined
char[] password; // the password as a character array
// ...
MongoCredential credential = MongoCredential.createScramSha256Credential(user, source, password);

MongoClient mongoClient = MongoClients.create(
        MongoClientSettings.builder()
                .applyToClusterSettings(builder ->
                        builder.hosts(Arrays.asList(new ServerAddress("host1", 27017))))
                .credential(credential)
                .build());

Or use a connection string that explicitly specifies the authMechanism=SCRAM-SHA-256:

MongoClient mongoClient = MongoClients.create("mongodb://user1:pwd1@host1/?authSource=db1&authMechanism=SCRAM-SHA-256");

SCRAM-SHA-1

To explicitly create a credential of type SCRAM-SHA-1, use the createScramSha1Credential method:

String user;     // the user name
String source;   // the source where the user is defined
char[] password; // the password as a character array
// ...
MongoCredential credential = MongoCredential.createScramSha1Credential(user, source, password);

MongoClient mongoClient = MongoClients.create(
        MongoClientSettings.builder()
                .applyToClusterSettings(builder -> 
                        builder.hosts(Arrays.asList(new ServerAddress("host1", 27017))))
                .credential(credential)
                .build());

Or use a connection string that explicitly specifies the authMechanism=SCRAM-SHA-1:

MongoClient mongoClient = MongoClients.create("mongodb://user1:pwd1@host1/?authSource=db1&authMechanism=SCRAM-SHA-1");

MONGODB-CR

To explicitly create a credential of type MONGODB-CR use the createMongCRCredential static factory method:

String user; // the user name
String database; // the name of the database in which the user is defined
char[] password; // the password as a character array
// ...
MongoCredential credential = MongoCredential.createMongoCRCredential(user, database, password);

MongoClient mongoClient = MongoClients.create(
        MongoClientSettings.builder()
                .applyToClusterSettings(builder -> 
                        builder.hosts(Arrays.asList(new ServerAddress("host1", 27017))))
                .credential(credential)
                .build());

Or use a connection string that explicitly specifies the authMechanism=MONGODB-CR:

MongoClient mongoClient = MongoClients.create("mongodb://user1:pwd1@host1/?authSource=db1&authMechanism=MONGODB-CR");

X.509

With X.509 mechanism, MongoDB uses the X.509 certificate presented during SSL negotiation to authenticate a user whose name is derived from the distinguished name of the X.509 certificate.

X.509 authentication requires the use of SSL connections with certificate validation. To create a credential of this type use the createMongoX509Credential static factory method:

String user;     // The X.509 certificate derived user name, e.g. "CN=user,OU=OrgUnit,O=myOrg,..."
// ...
MongoCredential credential = MongoCredential.createMongoX509Credential(user);

MongoClient mongoClient = MongoClients.create(
        MongoClientSettings.builder()
                .applyToClusterSettings(builder ->
                        builder.hosts(Arrays.asList(new ServerAddress("host1", 27017))))
                .credential(credential)
                .build());

Or use a connection string that explicitly specifies the authMechanism=MONGODB-X509:

MongoClient mongoClient = MongoClients.create("mongodb://subjectName@host1/?authMechanism=MONGODB-X509&ssl=true");

See the MongoDB server x.509 tutorial for more information about determining the subject name from the certificate.

Kerberos (GSSAPI)

MongoDB Enterprise supports proxy authentication through Kerberos service. To create a credential of type Kerberos (GSSAPI), use the createGSSAPICredential static factory method:

String user;   // The Kerberos user name, including the realm, e.g. "user1@MYREALM.ME"
// ...
MongoCredential credential = MongoCredential.createGSSAPICredential(user);

MongoClient mongoClient = MongoClients.create(
        MongoClientSettings.builder()
                .applyToClusterSettings(builder ->
                        builder.hosts(Arrays.asList(new ServerAddress("host1", 27017))))
                .credential(credential)
                .build());

Or use a connection string that explicitly specifies the authMechanism=GSSAPI:

MongoClient mongoClient = MongoClients.create("mongodb://username%40REALM.ME@host1/?authMechanism=GSSAPI");

To successfully authenticate via Kerberos, the application typically must specify several system properties so that the underlying GSSAPI Java libraries can acquire a Kerberos ticket:

java.security.krb5.realm=MYREALM.ME
java.security.krb5.kdc=mykdc.myrealm.me

Depending on the Kerberos setup, additional property specifications may be required, either via the application code or, in some cases, the withMechanismProperty() method of the MongoCredential instance:

• SERVICE_NAME

• CANONICALIZE_HOST_NAME

• JAVA_SUBJECT

• JAVA_SASL_CLIENT_PROPERTIES

For example, to specify the SERVICE_NAME property via the MongoCredential object:

credential = credential.withMechanismProperty(MongoCredential.SERVICE_NAME_KEY, "othername");

Or via the ConnectionString:

mongodb://username%40MYREALM.com@myserver/?authMechanism=GSSAPI&authMechanismProperties=SERVICE_NAME:othername

LDAP (PLAIN)

MongoDB Enterprise supports proxy authentication through a Lightweight Directory Access Protocol (LDAP) service. To create a credential of type LDAP use the createPlainCredential static factory method:

String user;          // The LDAP user name
char[] password;      // The LDAP password
// ...
MongoCredential credential = MongoCredential.createPlainCredential(user, "$external", password);
MongoClient mongoClient = MongoClients.create(
        MongoClientSettings.builder()
                .applyToClusterSettings(builder ->
                        builder.hosts(Arrays.asList(new ServerAddress("host1", 27017))))
                .credential(credential)
                .build());

Or use a connection string that explicitly specifies the authMechanism=PLAIN:

MongoClient mongoClient = MongoClients.create("mongodb://user1@host1/?authSource=$external&authMechanism=PLAIN");