From b1702d749e96cc0869b37bfd825e417cf809994c Mon Sep 17 00:00:00 2001
From: Seth Pollack <spollack@beenverified.com>
Date: Thu, 23 Feb 2017 11:55:52 -0500
Subject: [PATCH] validate region

---
 util/pkg/vfs/s3context.go | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

diff --git a/util/pkg/vfs/s3context.go b/util/pkg/vfs/s3context.go
index d67cdce942..ce3f913636 100644
--- a/util/pkg/vfs/s3context.go
+++ b/util/pkg/vfs/s3context.go
@@ -18,14 +18,16 @@ package vfs
 
 import (
 	"fmt"
+	"os"
+	"sync"
+	"time"
+
 	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/endpoints"
 	"github.com/aws/aws-sdk-go/aws/session"
 	"github.com/aws/aws-sdk-go/service/ec2"
 	"github.com/aws/aws-sdk-go/service/s3"
 	"github.com/golang/glog"
-	"os"
-	"sync"
-	"time"
 )
 
 type S3Context struct {
@@ -76,6 +78,10 @@ func (s *S3Context) getRegionForBucket(bucket string) (string, error) {
 		awsRegion = "us-east-1"
 	}
 
+	if err := validateRegion(awsRegion); err != nil {
+		return "", err
+	}
+
 	request := &s3.GetBucketLocationInput{
 		Bucket: &bucket,
 	}
@@ -155,3 +161,16 @@ func bruteforceBucketLocation(region *string, request *s3.GetBucketLocationInput
 		return nil, fmt.Errorf("Could not retrieve location for AWS bucket %s", *request.Bucket)
 	}
 }
+
+func validateRegion(region string) error {
+	resolver := endpoints.DefaultResolver()
+	partitions := resolver.(endpoints.EnumPartitions).Partitions()
+	for _, p := range partitions {
+		for _, r := range p.Regions() {
+			if r.ID() == region {
+				return nil
+			}
+		}
+	}
+	return fmt.Errorf("%s is not a valid region\nPlease check that your region is formatted correctly (i.e. us-east-1)", region)
+}