[ceph-users] radosgw - how to grant read-only access to another user by default

Hi, I'm new to radosgw (learned more about the MDS than I care to...), and it seems like the buckets and objects created by one user cannot be accessed by another user. Is there a way to make any content created by User A accessible (read-only) by User B? From the documentation it looks like this is handled as an S3 permission but I'm not finding an easy/obvious way to do this. Any help would be appreciated. Thanks in advance!