From 85bcacac905be0fb08696a5035dc1ce0dc89f377 Mon Sep 17 00:00:00 2001
From: Nick Craig-Wood <nick@craig-wood.com>
Date: Thu, 18 Jun 2020 17:50:50 +0100
Subject: [PATCH] s3: Cap expiry duration to 1 Week and return error when
 sharing dir

---
 backend/s3/s3.go | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/backend/s3/s3.go b/backend/s3/s3.go
index d287375c2..9cdc53401 100644
--- a/backend/s3/s3.go
+++ b/backend/s3/s3.go
@@ -965,6 +965,7 @@ const (
 
 	memoryPoolFlushTime = fs.Duration(time.Minute) // flush the cached buffers after this long
 	memoryPoolUseMmap   = false
+	maxExpireDuration   = fs.Duration(7 * 24 * time.Hour) // max expiry is 1 week
 )
 
 // Options defines the configuration for this backend
@@ -2021,9 +2022,16 @@ func (f *Fs) getMemoryPool(size int64) *pool.Pool {
 
 // PublicLink generates a public link to the remote path (usually readable by anyone)
 func (f *Fs) PublicLink(ctx context.Context, remote string, expire fs.Duration, unlink bool) (link string, err error) {
+	if strings.HasSuffix(remote, "/") {
+		return "", fs.ErrorCantShareDirectories
+	}
 	if _, err := f.NewObject(ctx, remote); err != nil {
 		return "", err
 	}
+	if expire > maxExpireDuration {
+		fs.Logf(f, "Public Link: Reducing expiry to %v as %v is greater than the max time allowed", maxExpireDuration, expire)
+		expire = maxExpireDuration
+	}
 	bucket, bucketPath := f.split(remote)
 	httpReq, _ := f.c.GetObjectRequest(&s3.GetObjectInput{
 		Bucket: &bucket,