SERVER-44858 Implement speculative sasl auth

 create mode 100644 jstests/auth/speculative-auth-replset.js
 create mode 100644 jstests/auth/speculative-sasl-start.js
 create mode 100644 jstests/ssl/speculative-auth-replset.js
 create mode 100644 jstests/ssl/speculative-authenticate.js
 create mode 100644 src/mongo/db/auth/sasl_commands.h
 create mode 100644 src/mongo/db/s/balancer/core_options_stub.cpp

3 files changed, 156 insertions, 2 deletions

diff --git a/jstests/auth/mongoURIAuth.js b/jstests/auth/mongoURIAuth.js
index 7688db2084e..abf518c5a98 100644
--- a/jstests/auth/mongoURIAuth.js
+++ b/jstests/auth/mongoURIAuth.js
@@ -68,6 +68,6 @@ runURIAuthTest(false, true, SCRAM_SHA_256, SCRAM_SHA_256_regex);
 jsTestLog("Test that a mechanism specified in CreateUser() is the chosen authentication method.");
 runURIAuthTest(true, false, SCRAM_SHA_1, SCRAM_SHA_1_regex);
 
-jsTestLog("Test that SCRAM-SHA-1 is the default authentication method.");
+jsTestLog("Test that SCRAM-SHA-256 is the default authentication method.");
 runURIAuthTest(false, false, SCRAM_SHA_256, SCRAM_SHA_256_regex);
-})();
\ No newline at end of file
+})();
diff --git a/jstests/auth/speculative-auth-replset.js b/jstests/auth/speculative-auth-replset.js
new file mode 100644
index 00000000000..65d83acba44
--- /dev/null
+++ b/jstests/auth/speculative-auth-replset.js
@@ -0,0 +1,58 @@
+// Verify that replica sets can speculatively authenticate
+// to each other during intra-cluster communication.
+// @tags: [requires_replication]
+
+(function() {
+'use strict';
+
+const rst = new ReplSetTest({nodes: 3, keyFile: 'jstests/libs/key1'});
+rst.startSet();
+rst.initiate();
+rst.awaitSecondaryNodes();
+
+const admin = rst.getPrimary().getDB('admin');
+admin.createUser({user: 'admin', pwd: 'pwd', roles: ['root']});
+admin.auth('admin', 'pwd');
+
+const baseURI = (function() {
+    let uri = 'mongodb://admin:pwd@';
+
+    for (let i = 0; i < rst.ports.length; ++i) {
+        if (i > 0) {
+            uri = uri + ',';
+        }
+        uri = uri + rst.host + ':' + rst.ports[i];
+    }
+
+    return uri + '/admin?replicaSet=' + rst.name;
+})();
+
+function test(uri) {
+    assert.eq(runMongoProgram('./mongo', uri, '--eval', ';'), 0);
+}
+
+// We've made no client connections for which speculation was possible,
+// since this connection came in during localhost auth bypass.
+// However we should have non-zero SCRAM-SHA-256 successes using internal auth.
+const mechStats =
+    assert.commandWorked(admin.runCommand({serverStatus: 1})).security.authentication.mechanisms;
+printjson(mechStats);
+assert(mechStats['SCRAM-SHA-256'] !== undefined);
+Object.keys(mechStats).forEach(function(mech) {
+    const stats = mechStats[mech].speculativeAuthenticate;
+
+    if (mech === 'SCRAM-SHA-256') {
+        assert.gte(stats.received, 2);
+    } else {
+        assert.eq(stats.received, 0);
+    }
+    assert.eq(stats.received, stats.successful);
+});
+
+test(baseURI);
+test(baseURI + '&authMechanism=SCRAM-SHA-1');
+test(baseURI + '&authMechanism=SCRAM-SHA-256');
+
+admin.logout();
+rst.stopSet();
+}());
diff --git a/jstests/auth/speculative-sasl-start.js b/jstests/auth/speculative-sasl-start.js
new file mode 100644
index 00000000000..a29d19815e7
--- /dev/null
+++ b/jstests/auth/speculative-sasl-start.js
@@ -0,0 +1,96 @@
+// Test for speculativeSaslStart during isMaster.
+
+(function() {
+'use strict';
+
+const mongod = MongoRunner.runMongod({auth: ''});
+const admin = mongod.getDB('admin');
+
+admin.createUser(
+    {user: 'admin', pwd: 'pwd', roles: ['root'], mechanisms: ['SCRAM-SHA-1', 'SCRAM-SHA-256']});
+admin.auth('admin', 'pwd');
+
+function test(uri, succeed) {
+    const shell = runMongoProgram('./mongo', uri, '--eval', ';');
+
+    if (succeed) {
+        assert.eq(0, shell);
+    } else {
+        assert.neq(0, shell);
+    }
+}
+
+function assertStats(cb) {
+    const mechStats = assert.commandWorked(admin.runCommand({serverStatus: 1}))
+                          .security.authentication.mechanisms;
+    cb(mechStats);
+}
+
+// No speculative auth attempts yet.
+assertStats(function(mechStats) {
+    Object.keys(mechStats).forEach(function(mech) {
+        const stats = mechStats[mech].speculativeAuthenticate;
+        assert.eq(stats.received, 0);
+        assert.eq(stats.successful, 0);
+    });
+});
+
+function expectN(mechStats, mech, N, M) {
+    const stats = mechStats[mech].speculativeAuthenticate;
+    assert.eq(N, stats.received);
+    assert.eq(M, stats.successful);
+}
+
+const baseOKURI = 'mongodb://admin:pwd@localhost:' + mongod.port + '/admin';
+
+// Speculate SCRAM-SHA-1
+test(baseOKURI + '?authMechanism=SCRAM-SHA-1', true);
+assertStats((s) => expectN(s, 'SCRAM-SHA-1', 1, 1));
+assertStats((s) => expectN(s, 'SCRAM-SHA-256', 0, 0));
+
+// Speculate SCRAM-SHA-256
+test(baseOKURI + '?authMechanism=SCRAM-SHA-256', true);
+assertStats((s) => expectN(s, 'SCRAM-SHA-1', 1, 1));
+assertStats((s) => expectN(s, 'SCRAM-SHA-256', 1, 1));
+
+// Fallback should speculate SCRAM-SHA-256
+test(baseOKURI, true);
+assertStats((s) => expectN(s, 'SCRAM-SHA-1', 1, 1));
+assertStats((s) => expectN(s, 'SCRAM-SHA-256', 2, 2));
+
+const baseFAILURI = 'mongodb://admin:haxx@localhost:' + mongod.port + '/admin';
+
+// Invalid password should never connect regardless of speculative auth.
+test(baseFAILURI + '?authMechanism=SCRAM-SHA-1', false);
+assertStats((s) => expectN(s, 'SCRAM-SHA-1', 2, 1));
+assertStats((s) => expectN(s, 'SCRAM-SHA-256', 2, 2));
+
+test(baseFAILURI + '?authMechanism=SCRAM-SHA-256', false);
+assertStats((s) => expectN(s, 'SCRAM-SHA-1', 2, 1));
+assertStats((s) => expectN(s, 'SCRAM-SHA-256', 3, 2));
+
+test(baseFAILURI, false);
+assertStats((s) => expectN(s, 'SCRAM-SHA-1', 2, 1));
+assertStats((s) => expectN(s, 'SCRAM-SHA-256', 4, 2));
+
+// Update admin use to only allow SCRAM-SHA-1
+
+admin.updateUser('admin', {mechanisms: ['SCRAM-SHA-1']});
+
+// Fallback (SCRAM-SHA-256) should fail to speculate.
+test(baseOKURI, true);
+assertStats((s) => expectN(s, 'SCRAM-SHA-1', 2, 1));
+assertStats((s) => expectN(s, 'SCRAM-SHA-256', 5, 2));
+
+// Explicit SCRAM-SHA-1 should successfully speculate.
+test(baseOKURI + '?authMechanism=SCRAM-SHA-1', true);
+assertStats((s) => expectN(s, 'SCRAM-SHA-1', 3, 2));
+assertStats((s) => expectN(s, 'SCRAM-SHA-256', 5, 2));
+
+// Explicit SCRAM-SHA-256 should fail to speculate or connect at all.
+test(baseOKURI + '?authMechanism=SCRAM-SHA-256', false);
+assertStats((s) => expectN(s, 'SCRAM-SHA-1', 3, 2));
+assertStats((s) => expectN(s, 'SCRAM-SHA-256', 6, 2));
+
+MongoRunner.stopMongod(mongod);
+})();