# Inspiration: https://github.com/Tecnativa/docker-socket-proxy/blob/master/haproxy.cfg

defaults
    timeout connect 10s
    timeout client 10s
    timeout server 10s

frontend http
    mode http
    bind :2375
    http-request deny unless { src 127.0.0.1 } || { src ::1 } || { src NC_IPV4_PLACEHOLDER } || { src NC_IPV6_PLACEHOLDER }
    http-request allow if { path,url_dec -m reg -i ^(/v[\d\.]+)?/containers/nc_app_[a-zA-Z0-9_.-]+/((json)|(start)|(stop)) } METH_GET
    http-request allow if { path,url_dec -m reg -i ^(/v[\d\.]+)?/containers/nc_app_[a-zA-Z0-9_.-]+ } METH_DELETE

    # ACL to restrict container name to nc_app_[a-zA-Z0-9_.-]+
    acl nc_app_container_name url_param(name) -m reg -i "^nc_app_[a-zA-Z0-9_.-]+"

    # ACL to restrict the number of Mounts to 1
    acl one_mount_volume req.body -m reg -i "\"Mounts\"\s*:\s*\[\s*(?:(?!\"Mounts\"\s*:\s*\[)[^}]*)}[^}]*\]"
    # ACL to deny if there are any binds
    acl binds_present req.body -m reg -i "\"HostConfig\"\s*:.*\"Binds\"\s*:"
    # ACL to restrict the type of Mounts to volume
    acl type_not_volume req.body -m reg -i "\"Mounts\":\s*\[[^\]]*(\"Type\":\s*\"(?!volume\b)\w+\"[^\]]*)+\]"
    http-request deny if { path,url_dec -m reg -i ^(/v[\d\.]+)?/containers/create } nc_app_container_name !one_mount_volume binds_present type_not_volume METH_POST

    # ACL to restrict container creation, that it has HostConfig.Privileged only set to false
    acl no_privileged_flag req.body -m reg -i "\"HostConfig\":\s?{[^}]*\"Privileged\":\s?false"
    # ACL to allow mount volume with strict pattern for name: nc_app_[a-zA-Z0-9_.-]+_data
    acl nc_app_volume_data_only req.body -m reg -i "\"Mounts\":\s?\[\s?{[^}]*\"Source\":\s?\"nc_app_[a-zA-Z0-9_.-]+_data\""
    http-request allow if { path,url_dec -m reg -i ^(/v[\d\.]+)?/containers/create } nc_app_container_name no_privileged_flag nc_app_volume_data_only METH_POST

    acl nc_app_volume_data req.body -m reg -i "\"Name\":\s?\"nc_app_[a-zA-Z0-9_.-]+_data\""
    http-request allow if { path,url_dec -m reg -i ^(/v[\d\.]+)?/volumes/create } nc_app_volume_data METH_POST
    http-request allow if { path,url_dec -m reg -i ^(/v[\d\.]+)?/volumes/nc_app_[a-zA-Z0-9_.-]+_data } METH_DELETE
    http-request allow if { path,url_dec -m reg -i ^(/v[\d\.]+)?/images/create } METH_POST
    http-request deny
    default_backend dockerbackend

backend dockerbackend
    mode http
    server dockersocket /var/run/docker.sock