Support migrating inconsistent bucket policies (#5855)

Previously we used allow bucket policies without
`Version` field to be set to any given value, but
this behavior is inconsistent with AWS S3.

PR #5790 addressed this by making bucket policies
stricter and cleaner, but this causes a breaking
change causing any existing policies perhaps without
`Version` field or the field to be empty to fail upon
server startup.

This PR brings a code to migrate under these scenarios
as a one time operation.
This commit is contained in:
Harshavardhana 2018-04-27 15:02:54 -07:00 committed by Dee Koder
parent 1bd7eb979c
commit b6ca39ea48
4 changed files with 40 additions and 9 deletions

View File

@ -79,6 +79,12 @@ func (api objectAPIHandlers) PutBucketPolicyHandler(w http.ResponseWriter, r *ht
return
}
// Version in policy must not be empty
if bucketPolicy.Version == "" {
writeErrorResponse(w, ErrMalformedPolicy, r.URL)
return
}
if err = objAPI.SetBucketPolicy(ctx, bucket, bucketPolicy); err != nil {
writeErrorResponse(w, toAPIErrorCode(err), r.URL)
return

View File

@ -110,6 +110,8 @@ func testPutBucketPolicyHandler(obj ObjectLayer, instanceType, bucketName string
// template for constructing HTTP request body for PUT bucket policy.
bucketPolicyTemplate := `{"Version":"2012-10-17","Statement":[{"Sid":"","Effect":"Allow","Principal":{"AWS":["*"]},"Action":["s3:GetBucketLocation","s3:ListBucket"],"Resource":["arn:aws:s3:::%s"]},{"Sid":"","Effect":"Allow","Principal":{"AWS":["*"]},"Action":["s3:GetObject"],"Resource":["arn:aws:s3:::%s/this*"]}]}`
bucketPolicyTemplateWithoutVersion := `{"Version":"","Statement":[{"Sid":"","Effect":"Allow","Principal":{"AWS":["*"]},"Action":["s3:GetBucketLocation","s3:ListBucket"],"Resource":["arn:aws:s3:::%s"]},{"Sid":"","Effect":"Allow","Principal":{"AWS":["*"]},"Action":["s3:GetObject"],"Resource":["arn:aws:s3:::%s/this*"]}]}`
// test cases with sample input and expected output.
testCases := []struct {
bucketName string
@ -207,7 +209,7 @@ func testPutBucketPolicyHandler(obj ObjectLayer, instanceType, bucketName string
// Test case - 8.
// non-existent bucket is used.
// writing BucketPolicy should fail.
// should result is 404 StatusNotFound
// should result in 404 StatusNotFound
{
bucketName: "non-existent-bucket",
bucketPolicyReader: bytes.NewReader([]byte(fmt.Sprintf(bucketPolicyTemplate, "non-existent-bucket", "non-existent-bucket"))),
@ -220,7 +222,7 @@ func testPutBucketPolicyHandler(obj ObjectLayer, instanceType, bucketName string
// Test case - 9.
// non-existent bucket is used (with invalid bucket name)
// writing BucketPolicy should fail.
// should result is 404 StatusNotFound
// should result in 404 StatusNotFound
{
bucketName: ".invalid-bucket",
bucketPolicyReader: bytes.NewReader([]byte(fmt.Sprintf(bucketPolicyTemplate, ".invalid-bucket", ".invalid-bucket"))),
@ -230,6 +232,19 @@ func testPutBucketPolicyHandler(obj ObjectLayer, instanceType, bucketName string
secretKey: credentials.SecretKey,
expectedRespStatus: http.StatusNotFound,
},
// Test case - 10.
// Existent bucket with policy with Version field empty.
// writing BucketPolicy should fail.
// should result in 400 StatusBadRequest.
{
bucketName: bucketName,
bucketPolicyReader: bytes.NewReader([]byte(fmt.Sprintf(bucketPolicyTemplateWithoutVersion, bucketName, bucketName))),
policyLen: len(fmt.Sprintf(bucketPolicyTemplateWithoutVersion, bucketName, bucketName)),
accessKey: credentials.AccessKey,
secretKey: credentials.SecretKey,
expectedRespStatus: http.StatusBadRequest,
},
}
// Iterating over the test cases, calling the function under test and asserting the response.

View File

@ -24,6 +24,7 @@ import (
"sync"
miniogopolicy "github.com/minio/minio-go/pkg/policy"
"github.com/minio/minio/cmd/logger"
"github.com/minio/minio/pkg/handlers"
"github.com/minio/minio/pkg/policy"
)
@ -87,6 +88,20 @@ func (sys *PolicySys) Init(objAPI ObjectLayer) error {
return err
}
} else {
// This part is specifically written to handle migration
// when the Version string is empty, this was allowed
// in all previous minio releases but we need to migrate
// those policies by properly setting the Version string
// from now on.
if config.Version == "" {
logger.Info("Found in-consistent bucket policies, Migrating them for Bucket: (%s)", bucket.Name)
config.Version = policy.DefaultVersion
if err = savePolicyConfig(objAPI, bucket.Name, config); err != nil {
return err
}
}
sys.Set(bucket.Name, *config)
}
}
@ -143,12 +158,7 @@ func GetPolicyConfig(objAPI ObjectLayer, bucketName string) (*policy.Policy, err
return nil, err
}
bucketPolicy, err := policy.ParseConfig(reader, bucketName)
if err != nil {
return nil, err
}
return bucketPolicy, nil
return policy.ParseConfig(reader, bucketName)
}
func savePolicyConfig(objAPI ObjectLayer, bucketName string, bucketPolicy *policy.Policy) error {

View File

@ -77,7 +77,7 @@ func (policy Policy) IsEmpty() bool {
// isValid - checks if Policy is valid or not.
func (policy Policy) isValid() error {
if policy.Version != DefaultVersion {
if policy.Version != DefaultVersion && policy.Version != "" {
return fmt.Errorf("invalid version '%v'", policy.Version)
}