A collection of small fixes (#623)

airbnb · Mar 14, 2018 · e149e6e · e149e6e
1 parent c39814b
commit e149e6e
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Showing 17 changed files with 101 additions and 102 deletions.
diff --git a/conf/lambda.json b/conf/lambda.json
@@ -17,7 +17,6 @@
     "source_bucket": "PREFIX_GOES_HERE.streamalert.source",
     "source_current_hash": "<auto_generated>",
     "source_object_key": "<auto_generated>",
-    "third_party_libraries": [],
     "timeout": 60,
     "vpc_config": {
       "security_group_ids": [],
@@ -37,7 +36,6 @@
     "handler": "app_integrations.main.handler",
     "source_bucket": "PREFIX_GOES_HERE.streamalert.source",
     "source_current_hash": "<auto_generated>",
-    "source_object_key": "<auto_generated>",
-    "third_party_libraries": []
+    "source_object_key": "<auto_generated>"
   }
-}
+}
diff --git a/conf/sources.json b/conf/sources.json
@@ -16,6 +16,13 @@
       ]
     }
   },
+  "sns": {
+    "prefix_cluster_sample_topic": {
+      "logs": [
+        "binaryalert"
+      ]
+    }
+  },
   "stream_alert_app": {
     "prefix_cluster_box_admin_events_sm-app-name_app": {
       "logs": [

diff --git a/rules/community/binaryalert/__init__.py b/rules/community/binaryalert/__init__.py
diff --git a/rules/community/binaryalert/binaryalert_yara_match.py b/rules/community/binaryalert/binaryalert_yara_match.py
@@ -0,0 +1,15 @@
+"""Alert on destructive AWS API calls."""
+from stream_alert.rule_processor.rules_engine import StreamRules
+
+rule = StreamRules.rule
+
+
+@rule(logs=['binaryalert'],
+      outputs=['aws-sns:sample-topic'])
+def binaryalert_yara_match(rec):
+    """
+    author:       Austin Byers (Airbnb CSIRT)
+    description:  BinaryAlert found a binary matching a YARA rule
+    reference:    https://binaryalert.io
+    """
+    return rec['NumMatchedRules'] > 0
diff --git a/stream_alert/alert_processor/main.py b/stream_alert/alert_processor/main.py
@@ -13,6 +13,7 @@
 See the License for the specific language governing permissions and
 limitations under the License.
 """
+from __future__ import absolute_import  # Suppresses RuntimeWarning import error in Lambda
 from collections import OrderedDict
 import json
 

diff --git a/stream_alert/athena_partition_refresh/main.py b/stream_alert/athena_partition_refresh/main.py
@@ -13,6 +13,7 @@
 See the License for the specific language governing permissions and
 limitations under the License.
 """
+from __future__ import absolute_import  # Suppresses RuntimeWarning import error in Lambda
 from collections import defaultdict
 from datetime import datetime
 import json

diff --git a/stream_alert/rule_processor/main.py b/stream_alert/rule_processor/main.py
@@ -13,6 +13,7 @@
 See the License for the specific language governing permissions and
 limitations under the License.
 """
+from __future__ import absolute_import  # Suppresses RuntimeWarning import error in Lambda
 import importlib
 import os
 

diff --git a/stream_alert/threat_intel_downloader/main.py b/stream_alert/threat_intel_downloader/main.py
@@ -13,6 +13,7 @@
 See the License for the specific language governing permissions and
 limitations under the License.
 """
+from __future__ import absolute_import  # Suppresses RuntimeWarning import error in Lambda
 import json
 import os
 

diff --git a/stream_alert_cli/helpers.py b/stream_alert_cli/helpers.py
@@ -29,11 +29,13 @@
 from botocore.exceptions import ClientError
 from moto import (
     mock_cloudwatch,
-    mock_kms,
+    mock_dynamodb2,
     mock_kinesis,
+    mock_kms,
     mock_lambda,
     mock_s3,
-    mock_dynamodb2,
+    mock_sns,
+    mock_sqs
 )
 
 from stream_alert_cli.logger import LOGGER_CLI
@@ -522,10 +524,12 @@ def wrap(func):
         """Wrap the returned function with or without mocks"""
         if context.mocked:
             @mock_cloudwatch
+            @mock_kinesis
+            @mock_kms
             @mock_lambda
             @mock_s3
-            @mock_kms
-            @mock_kinesis
+            @mock_sns
+            @mock_sqs
             def mocked(options, context):
                 """This function is now mocked using moto mock decorators to
                 override any boto3 calls. Wrapping this function here allows

diff --git a/stream_alert_cli/manage_lambda/package.py b/stream_alert_cli/manage_lambda/package.py
@@ -231,7 +231,7 @@ def _resolve_third_party(self, temp_package_path):
 
         # Add any custom libs needed by rules, etc
         third_party_libs.update(
-            set(self.config['lambda'][self.config_key]['third_party_libraries']))
+            set(self.config['lambda'][self.config_key].get('third_party_libraries', [])))
 
         # Return a default of True here if no libraries to install
         if not third_party_libs:

diff --git a/stream_alert_cli/terraform/threat_intel_downloader.py b/stream_alert_cli/terraform/threat_intel_downloader.py
@@ -55,7 +55,6 @@ def generate_threat_intel_downloader(config):
                                              ['expiration_ts', 'itype', 'source', 'type', 'value']),
         'ioc_filters': ti_downloader_config.get('ioc_filters', ['crowdstrike', '@airbnb.com']),
         'ioc_types': ti_downloader_config.get('ioc_types', ['domain', 'ip', 'md5']),
-        'autoscale': ti_downloader_config.get('autoscale', False),
         'max_read_capacity': ti_downloader_config.get('max_read_capacity', '5'),
         'min_read_capacity': ti_downloader_config.get('min_read_capacity', '5'),
         'target_utilization': ti_downloader_config.get('target_utilization', '70')

diff --git a/stream_alert_cli/test.py b/stream_alert_cli/test.py
@@ -772,6 +772,15 @@ def setup_outputs(self, alert):
                     lambda_function = parts[-1]
                 helpers.create_lambda_function(lambda_function,
                                                self.region)
+
+            elif service == 'aws-sns':
+                topic_name = self.outputs_config[service][descriptor]
+                boto3.client('sns', region_name=self.region).create_topic(Name=topic_name)
+
+            elif service == 'aws-sqs':
+                queue_name = self.outputs_config[service][descriptor]
+                boto3.client('sqs', region_name=self.region).create_queue(QueueName=queue_name)
+
             elif service == 'komand':
                 output_name = '{}/{}'.format(service, descriptor)
                 creds = {'komand_auth_token': '00000000-0000-0000-0000-000000000000',

diff --git a/terraform/modules/tf_stream_alert_globals/main.tf b/terraform/modules/tf_stream_alert_globals/main.tf
@@ -19,19 +19,16 @@ resource "aws_dynamodb_table" "alerts_table" {
     name = "RuleName"
     type = "S"
   }
-
   attribute {
     name = "Timestamp"
     type = "S"
   }
-
   // Enable expriation time while testing Dynamo table for alerts
   // TODO: Remove TTL once Alert Merger is implemented
   ttl {
     attribute_name = "TTL"
     enabled        = true
   }
-
   tags {
     Name = "StreamAlert"
   }

diff --git a/terraform/modules/tf_threat_intel_downloader/dynamodb.tf b/terraform/modules/tf_threat_intel_downloader/dynamodb.tf
@@ -26,95 +26,16 @@ resource "aws_dynamodb_table" "threat_intel_ioc" {
   }
 }
 
-// IAM Role: Application autoscalling role
-resource "aws_iam_role" "stream_alert_dynamodb_appautoscaling" {
-  count              = "${var.autoscale ? 1 : 0}"
-  name               = "${var.prefix}_streamalert_dynamodb_appautoscaling"
-  assume_role_policy = "${data.aws_iam_policy_document.appautoscaling_assume_role_policy.json}"
-}
-
-// IAM Policy Doc: Generic Application Autoscaling AssumeRole
-data "aws_iam_policy_document" "appautoscaling_assume_role_policy" {
-  count = "${var.autoscale ? 1 : 0}"
-
-  statement {
-    effect  = "Allow"
-    actions = ["sts:AssumeRole"]
-
-    principals {
-      type        = "Service"
-      identifiers = ["application-autoscaling.amazonaws.com"]
-    }
-  }
-}
-
-// IAM Role Policy: Allow appautoscaling IAM role to autoscaling DynamoDB table
-resource "aws_iam_role_policy" "appautoscaling_update_table" {
-  count  = "${var.autoscale ? 1 : 0}"
-  name   = "DynamoDBAppAutoscaleUpdateTablePolicy"
-  role   = "${aws_iam_role.stream_alert_dynamodb_appautoscaling.id}"
-  policy = "${data.aws_iam_policy_document.appautoscaling_update_table.json}"
-}
-
-// IAM Policy Doc: Allow autoscaling IAM role to send alarm to CloudWatch
-// and change table settings for autoscaling.
-// This policy is allow the role to change table settings
-data "aws_iam_policy_document" "appautoscaling_update_table" {
-  count = "${var.autoscale ? 1 : 0}"
-
-  statement {
-    effect = "Allow"
-
-    actions = [
-      "dynamodb:DescribeTable",
-      "dynamodb:UpdateTable",
-    ]
-
-    resources = [
-      "${aws_dynamodb_table.threat_intel_ioc.arn}",
-    ]
-  }
-}
-
-// IAM Role Policy: Allow appautoscaling IAM role to autoscaling DynamoDB table
-resource "aws_iam_role_policy" "appautoscaling_cloudwatch_alarms" {
-  count  = "${var.autoscale ? 1 : 0}"
-  name   = "DynamoDBAppAutoscaleCloudWatchAlarmsPolicy"
-  role   = "${aws_iam_role.stream_alert_dynamodb_appautoscaling.id}"
-  policy = "${data.aws_iam_policy_document.appautoscaling_cloudwatch_alarms.json}"
-}
-
-// IAM Policy Doc: This policy is allow the role to send alarm to CloudWatch.
-data "aws_iam_policy_document" "appautoscaling_cloudwatch_alarms" {
-  count = "${var.autoscale ? 1 : 0}"
-
-  statement {
-    effect = "Allow"
-
-    actions = [
-      "cloudwatch:PutMetricAlarm",
-      "cloudwatch:DescribeAlarms",
-      "cloudwatch:GetMetricStatistics",
-      "cloudwatch:SetAlarmState",
-      "cloudwatch:DeleteAlarms",
-    ]
-
-    resources = ["*"]
-  }
-}
-
 resource "aws_appautoscaling_target" "dynamodb_table_read_target" {
-  count              = "${var.autoscale ? 1 : 0}"
   max_capacity       = "${var.max_read_capacity}"
   min_capacity       = "${var.min_read_capacity}"
-  resource_id        = "table/${var.prefix}_streamalert_threat_intel_downloader"
-  role_arn           = "${aws_iam_role.stream_alert_dynamodb_appautoscaling.arn}"
+  resource_id        = "table/${aws_dynamodb_table.threat_intel_ioc.name}"
+  role_arn           = "arn:aws:iam::${var.account_id}:role/aws-service-role/dynamodb.application-autoscaling.amazonaws.com/AWSServiceRoleForApplicationAutoScaling_DynamoDBTable"
   scalable_dimension = "dynamodb:table:ReadCapacityUnits"
   service_namespace  = "dynamodb"
 }
 
 resource "aws_appautoscaling_policy" "dynamodb_table_read_policy" {
-  count              = "${var.autoscale ? 1 : 0}"
   name               = "DynamoDBReadCapacityUtilization:${aws_appautoscaling_target.dynamodb_table_read_target.resource_id}"
   policy_type        = "TargetTrackingScaling"
   resource_id        = "${aws_appautoscaling_target.dynamodb_table_read_target.resource_id}"

diff --git a/terraform/modules/tf_threat_intel_downloader/variables.tf b/terraform/modules/tf_threat_intel_downloader/variables.tf
@@ -71,10 +71,6 @@ variable "log_retention" {
   default = 14
 }
 
-variable "autoscale" {
-  default = false
-}
-
 variable "max_read_capacity" {
   default = 5
 }

diff --git a/tests/integration/rules/binaryalert/binaryalert_yara_match.json b/tests/integration/rules/binaryalert/binaryalert_yara_match.json
@@ -0,0 +1,50 @@
+{
+  "records": [
+    {
+      "data": {
+        "FileInfo": {
+          "MD5": "...",
+          "S3LastModified": "...",
+          "S3Location": "...",
+          "S3Metadata": {},
+          "SHA256": "..."
+        },
+        "MatchedRules": {
+          "Rule1": {
+            "MatchedStrings": [
+              "$eicar_regex"
+            ],
+            "Meta": {
+              "author": "Austin Byers (Airbnb CSIRT)",
+              "description": "This is a standard AV test, intended to check whether BinaryAlert is working correctly.",
+              "reference": "http://www.eicar.org/86-0-Intended-use.html"
+            },
+            "RuleFile": "eicar.yar",
+            "RuleName": "eicar_av_test",
+            "RuleTags": []
+          }
+        },
+        "NumMatchedRules": "1"
+      },
+      "description": "All YARA matches from BinaryAlert trigger an alert",
+      "log": "binaryalert",
+      "service": "sns",
+      "source": "prefix_cluster_sample_topic",
+      "trigger_rules": [
+        "binaryalert_yara_match"
+      ]
+    },
+    {
+      "data": {
+        "FileInfo": {},
+        "MatchedRules": {},
+        "NumMatchedRules": "0"
+      },
+      "description": "No alerts triggered if no YARA rules were matched",
+      "log": "binaryalert",
+      "service": "sns",
+      "source": "prefix_cluster_sample_topic",
+      "trigger_rules": []
+    }
+  ]
+}
diff --git a/tests/unit/stream_alert_athena_partition_refresh/test_main.py b/tests/unit/stream_alert_athena_partition_refresh/test_main.py
@@ -175,14 +175,13 @@ def test_handler_no_received_messages(
     @patch('stream_alert.athena_partition_refresh.main.LOGGER')
     @patch('stream_alert.athena_partition_refresh.main._load_config',
            return_value=CONFIG_DATA)
-    @patch('stream_alert.athena_partition_refresh.main.'
-           'StreamAlertSQSClient.unique_s3_buckets_and_keys',
-           return_value={})
+    @patch('stream_alert.athena_partition_refresh.main.StreamAlertSQSClient')
     @mock_sqs
-    def test_handler_no_unique_buckets(self, _, mock_config, mock_logging):
+    def test_handler_no_unique_buckets(self, mock_sqs_client, mock_config, mock_logging):
         """Athena - Handler - No Unique Buckets"""
         test_sqs_client = TestStreamAlertSQSClient()
         test_sqs_client.setup()
+        mock_sqs_client.return_value.unique_s3_buckets_and_keys = lambda: {}
 
         handler(None, None)