ova: fix the version of encoding/gob

Unfortunately, we rely on 'encoding/gob' to determine the UUID of VMs
from OVAs and this package has changed in Go 1.21 in a way we get a
different UUID compared to the one we get with Go 1.20 for the same
input, which could break existing OVA providers.

Therefore, this package integrates the relevant pieces from
'encoding/gob' of Go 1.20 so that we can bump Go to 1.21 without
breaking compatibility with OVA providers that were defined in lower
versions of Forklift.

Signed-off-by: Arik Hadas <[email protected]>

.golangci.yml

@@ -1,3 +1,6 @@
+run:
+  skip-dirs:
+    - pkg/lib/gob
 linters:
   enable:
   - ginkgolinter

cmd/ova-provider-server/BUILD.bazel

@@ -5,7 +5,10 @@ go_library(
     srcs = ["ova-provider-server.go"],
     importpath = "github.com/konveyor/forklift-controller/cmd/ova-provider-server",
     visibility = ["//visibility:private"],
-    deps = ["//vendor/github.com/google/uuid"],
+    deps = [
+        "//pkg/lib/gob",
+        "//vendor/github.com/google/uuid",
+    ],
 )
 
 go_binary(

cmd/ova-provider-server/ova-provider-server.go

@@ -4,7 +4,6 @@ import (
 	"archive/tar"
 	"bytes"
 	"crypto/sha256"
-	"encoding/gob"
 	"encoding/hex"
 	"encoding/json"
 	"encoding/xml"
@@ -17,6 +16,8 @@ import (
 	"strconv"
 	"strings"
 
+	"github.com/konveyor/forklift-controller/pkg/lib/gob"
+
 	"github.com/google/uuid"
 )
 

pkg/lib/gob/BUILD.bazel

@@ -0,0 +1,15 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "gob",
+    srcs = [
+        "decoder.go",
+        "enc_helpers.go",
+        "encode.go",
+        "encoder.go",
+        "error.go",
+        "type.go",
+    ],
+    importpath = "github.com/konveyor/forklift-controller/pkg/lib/gob",
+    visibility = ["//visibility:public"],
+)

pkg/lib/gob/decoder.go

@@ -0,0 +1,10 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gob
+
+// tooBig provides a sanity check for sizes; used in several places. Upper limit
+// of is 1GB on 32-bit systems, 8GB on 64-bit, allowing room to grow a little
+// without overflow.
+const tooBig = (1 << 30) << (^uint(0) >> 62)