fix: enforce 5gb copy source object size threshold.

Fixes #1896

Enforces the S3 `5 GiB` copy source size limit across the posix and azure
backends for `CopyObject` and `UploadPartCopy`, returning `InvalidRequest` when
the source object exceeds the threshold.

The limit is now configurable via `--copy-object-threshold`
(`VGW_COPY_OBJECT_THRESHOLD`, default 5 GiB).
A new `--mp-max-parts flag` (`VGW_MP_MAX_PARTS`, default `10000`) has been added to make multipart upload parts number limit configurable.

No integration test has been added, as GitHub Actions cannot reliably
handle large objects.

s3api/controllers/admin_test.go

@@ -681,7 +681,7 @@ func TestAdminController_CreateBucket(t *testing.T) {
 				},
 			}
 
-			s3api := New(be, iam, nil, nil, nil, false, false, "")
+			s3api := New(be, iam, nil, nil, nil, false, false, "", 10000)
 
 			ctrl := AdminController{
 				iam:   iam,

s3api/controllers/base.go

@@ -38,6 +38,7 @@ type S3ApiController struct {
 	logger        s3log.AuditLogger
 	evSender      s3event.S3EventSender
 	mm            metrics.Manager
+	mpMaxParts    int
 	readonly      bool
 	disableACL    bool
 	virtualDomain string
@@ -60,7 +61,7 @@ var (
 	xmlhdr = []byte(`<?xml version="1.0" encoding="UTF-8"?>` + "\n")
 )
 
-func New(be backend.Backend, iam auth.IAMService, logger s3log.AuditLogger, evs s3event.S3EventSender, mm metrics.Manager, readonly, disableACL bool, virtualDomain string) S3ApiController {
+func New(be backend.Backend, iam auth.IAMService, logger s3log.AuditLogger, evs s3event.S3EventSender, mm metrics.Manager, readonly, disableACL bool, virtualDomain string, mpMaxParts int) S3ApiController {
 	return S3ApiController{
 		be:            be,
 		iam:           iam,
@@ -70,6 +71,7 @@ func New(be backend.Backend, iam auth.IAMService, logger s3log.AuditLogger, evs
 		mm:            mm,
 		disableACL:    disableACL,
 		virtualDomain: virtualDomain,
+		mpMaxParts:    mpMaxParts,
 	}
 }
 

s3api/controllers/object-put.go

@@ -282,7 +282,7 @@ func (c S3ApiController) UploadPart(ctx *fiber.Ctx) (*Response, error) {
 		}, err
 	}
 
-	if partNumber < minPartNumber || partNumber > maxPartNumber {
+	if partNumber < minPartNumber || partNumber > int32(c.mpMaxParts) {
 		debuglogger.Logf("invalid part number: %d", partNumber)
 		return &Response{
 			MetaOpts: &MetaOptions{

s3api/controllers/object-put_test.go

@@ -607,7 +607,8 @@ func TestS3ApiController_UploadPart(t *testing.T) {
 			}
 
 			ctrl := S3ApiController{
-				be: be,
+				be:         be,
+				mpMaxParts: 10000,
 			}
 
 			testController(

s3api/router.go

@@ -42,10 +42,11 @@ type S3ApiRouter struct {
 	region          string
 	virtualDomain   string
 	corsAllowOrigin string
+	mpMaxParts      int
 }
 
 func (sa *S3ApiRouter) Init() {
-	ctrl := controllers.New(sa.be, sa.iam, sa.logger, sa.evs, sa.mm, sa.readonly, sa.disableACL, sa.virtualDomain)
+	ctrl := controllers.New(sa.be, sa.iam, sa.logger, sa.evs, sa.mm, sa.readonly, sa.disableACL, sa.virtualDomain, sa.mpMaxParts)
 	sa.Ctrl = ctrl
 	adminServices := &controllers.Services{
 		Logger: sa.aLogger,

s3api/server.go

@@ -175,6 +175,11 @@ func WithReadOnly() Option {
 	return func(s *S3ApiServer) { s.Router.readonly = true }
 }
 
+// WithMpMaxParts sets the maximum number of parts allowed in a multipart upload.
+func WithMpMaxParts(n int) Option {
+	return func(s *S3ApiServer) { s.Router.mpMaxParts = n }
+}
+
 // WithHostStyle enabled host-style bucket addressing on the server
 func WithHostStyle(virtualDomain string) Option {
 	return func(s *S3ApiServer) {