User cannot read password file

With the caveat that I'm very new to docker...

Inside the container, /certificates is owned by the uid of the user who created $(pwd)/certificates on the host. When the container runs with the "ca" parameter, uid=1000 (hagrid) expects to be able to have access to /certificates/password. Since the file's owner on the host is not uid 1000, "${KEYMASTER} ca" fails:

host$ $ docker -v
Docker version 1.6.0, build 4749651
host$ ${KEYMASTER} ca
cat: /certificates/password: Permission denied
host$ docker run -it --rm -v $(pwd)/certificates/:/certificates/ cloudpipe/keymaster /bin/bash
hagrid@string:~$ ls -l /certificates/password
-rw------- 1 2354 2354 175 May 7 00:08 password
hagrid@string:~$ id
uid=1000(hagrid) gid=1000(hagrid) groups=1000(hagrid)