Connection Manager ****************** Copyright (C) 2007-2012 Intel Corporation. All rights reserved. Functionality and features ========================== The following features are built-in into Connection Manager: - Generic plugin infrastructure - Device and network abstraction (with basic storage support) - IPv4, IPv4-LL (link-local) and DHCP - IPv6, DHCPv6 and 6to4 tunnels - Advanced routing and DNS configuration - Built-in DNS proxy and intelligent caching - Built-in WISPr hotspot logins and portal detection - Time and timezone configuration (manual and automatic with NTP) - Proxy handling (manual and automatic with WPAD) - Tethering support (USB, Bluetooth and WiFi AP mode) - Detailed statistics handling (home and roaming) Various plugins can be enabled for networking support: - Ethernet plugin - WiFi plugin with WEP40/WEP128 and WPA/WPA2 (personal and enterprise) - Bluetooth plugin (using BlueZ) - 2G/3G/4G plugin (using oFono) Also plugins with additional features are available: - Loopback interface setup - PACrunner proxy handling - PolicyKit authorization support Note that when ConnMan starts, it clears all network interfaces that are going to be used. If this is not desired, network interfaces can be ignored either by setting NetworkInterfaceBlacklist in the main.conf config file or by using the -I command line option. Compilation and installation ============================ In order to compile Connection Manager you need following software packages: - GCC compiler - GLib library - D-Bus library - IP-Tables library (for tethering support) - GnuTLS library (optional) - PolicyKit (optional) - readline (command line client) To configure run: ./configure --prefix=/usr --sysconfdir=/etc --localstatedir=/var Configure automatically searches for all required components and packages. To compile and install run: make && make install Configuration and options ========================= For a working system, certain configuration options need to be enabled: --disable-ethernet Disable support for Ethernet network cards By default Ethernet technology support is built-in and enabled. This option can be used to build a small daemon for a specific system if Ethernet support is not required. --disable-gadget Disable support for USB Ethernet Gadget devices By default USB Ethernet Gadget technology support is built-in and enabled. This option can be used to build a small daemon for a specific system if USB Ethernet Gadget support is not required. --disable-wifi Disable support for WiFi devices By default WiFi technology support is built-in and enabled. This option can be used to build a small daemon for a specific system if WiFi support is not required. It is safe to build a daemon with WiFi support and no running wpa_supplicant. The start of wpa_supplicant is automatically detected and only a runtime dependency. It is not needed to build ConnMan. --disable-bluetooth Disable support for Bluetooth devices By default Bluetooth technology support is built-in and enabled. This option can be used to build a small daemon for a specific system if Bluetooth support is not required. It is safe to build a daemon with Bluetooth support and no running bluetoothd. The start of bluetoothd is automatically detected and only a runtime dependency. It is not needed to build ConnMan. --disable-ofono Disable support for cellular 2G/3G/4G devices By default oFono technology support is built-in and enabled. This option can be used to build a small daemon for a specific system where oFono is not used. It is safe to build a daemon with oFono support and no running ofonod. That start of ofonod is automatically detected and only a runtime dependency. It is not needed to build ConnMan. --disable-dundee Disable support for Bluetooth DUN devices By default Bluetooth DUN technology (dundee) support is built-in and enabled. This option can be used to build a small daemon for a specific system where dundee is not used. It is safe to build a daemon with dundee support and no running dundee. That start of dundee is automatically detected and only a runtime dependency. It is not needed to build ConnMan. --enable-iwd Enable support for Wireless daemon for Linux The IWD project does not have initial release so far, therefore by default IWD support is not enabled. It is safe to enable this option along WiFi support. --disable-pacrunner Disable support for PACrunner proxy handling By default PACrunner support is built-in and enabled. This option can be used to build a small daemon for a specific system where PACrunner is not used. It is safe to build a daemon with PACrunner support and no pacrunner daemon. It will detect and start a PACrunner process if needed at runtime. The presence is not needed to build ConnMan. --disable-loopback Disable setup of loopback device For distributions with a really minimal init system and no networking scripts this can take care of setting up the loopback device and enabling it. It is safe to leave this selected even if networking scripts are in place. It detects an already configured loopback device and leaves it as it is. --disable-wispr Disable support for WISPr hotspot logins For systems with really minimal memory requirements, this will disable the support for WISPr hotspot logins. The code for WISPr will be still compiled into the daemon, but its requirement on GnuTLS for secure connections will be lifted. The missing GnuTLS support shrinks the memory requirements by about 30% and for systems that are more stationary and do not log into hotspots this might be a better trade off. Disabling WISPr support is not disabling the portal detection support. A portal will still be detected, but instead of being asked for login credentials, the request for a browser session will be made through the agent. --enable-polkit Enable support for PolicyKit authorization This allows to check every D-Bus access against a security policy and so restrict access to certain functionality. --enable-nmcompat Enable support for NetworkManager compatibility interfaces This allows to expose a minimal set of NetworkManager interfaces. It is useful for systems with applications written to use NetworkManager to detect online/offline status and have not yet been converted to use ConnMan. --disable-client Disable support for the command line client By default the command line client is enabled and uses the readline library. For specific systems where ConnMan is configured by other means, the command line client can be disabled and the dependency on readline is removed. --enable-selinux Enable support for compiling SElinux type enforcement rules The TE rules are needed if host environment is in enforcing mode. Without this option, the VPN client process cannot send notification to connman-vpnd via net.connman.Task interface. The compiled connman-task.pp module needs to also installed using this command # semodule -i connman-task.pp in order to enable the dbus access. Activating debugging ==================== One can activate debugging prints in ConnMan using -d command line option. If the -d option has no parameters, then debugging is activated for all source code files. If the -d option has parameters, they tell which source code files have debugging activated. One can use wild cards in file names. Example: -d Activate all normal debug prints -d src/service.c This prints debugging info from src/service.c file only -d src/network.c:src/ipconfig.c This activates debug prints in src/network.c and src/ipconfig.c files. -d 'src/n*.c' This would activate debug print from all the C source files starting with letter 'n' in src directory. Note the quotation marks around option, that is to prevent shell expansion. -d '*/n*.c:*/i*.c' Activate debug prints for all C source files starting with letters 'n' or 'i' in any sub-directory. Some components of ConnMan have environment variable activated debug prints. If the environment variable is set, then corresponding component will print some extra debugging information. Following environment variables can be used: CONNMAN_DHCP_DEBUG DHCPv4 related debug information CONNMAN_DHCPV6_DEBUG DHCPv6 related debug information CONNMAN_IPTABLES_DEBUG Extra information when iptables is used CONNMAN_RESOLV_DEBUG Name resolver debug prints. These debug prints are used when ConnMan resolves host names for its own use. Note that the DNS proxy debug prints do not use this environment variable. For that, one can use "-d src/dnsproxy.c" command line option. CONNMAN_SUPPLICANT_DEBUG Debugging prints for communication between connmand and wpa_supplicant processes. CONNMAN_WEB_DEBUG Debug information when ConnMan does Internet connectivity check in Wispr and 6to4 components. Example: CONNMAN_WEB_DEBUG=1 src/connmand -n If timing conditions are relevant then it is recommended command to get log traces as follows: connmand -d 2>&1 | ts '[%H:%M:%.S]' | tee connman.log The 'ts' program is normaly avialable in the moreutils package. Kernel configuration ==================== In order to support tethering, the following kernel configuration options need to be enabled either as modules (m) or builtin (y): CONFIG_BRIDGE CONFIG_IP_NF_TARGET_MASQUERADE In order to enable CONFIG_IP_NF_TARGET_MASQUERADE, the following options need to be enabled also as modules (m) or builtin (y): CONFIG_NETFILTER CONFIG_NF_CONNTRACK_IPV4 CONFIG_NF_NAT_IPV4 For routing and statistic support in Sessions, the following options need to be enabled as modules (m) or builtin (y): CONFIG_IP_NF_IPTABLES CONFIG_IP_MULTIPLE_TABLES CONFIG_NETFILTER_NETLINK_ACCT CONFIG_NETFILTER_XT_MATCH_NFACCT CONFIG_NETFILTER_XT_CONNMARK CONFIG_NETFILTER_XT_TARGET_CONNMARK CONFIG_NETFILTER_XT_MATCH_CONNMARK In order to support USB gadget tethering, the following kernel configuration options need to be enabled: CONFIG_USB_GADGET CONFIG_USB_ETH wpa_supplicant configuration ============================ In order to get wpa_supplicant and Connection Manager working properly together you should edit wpa_supplicant .config file and set: CONFIG_WPS=y CONFIG_AP=y CONFIG_CTRL_IFACE_DBUS_NEW=y add: CONFIG_BGSCAN_SIMPLE=y This last option will enable the support of background scanning while being connected, which is necessary when roaming on wifi. It is recommended to use wpa_supplicant 2.x or later. If wpa_supplicant is configured to D-Bus autostart, then ConnMan will trigger the autostart of wpa_supplicant. However please keep in mind that this trigger only happens once. If wpa_supplicant stops or crashes, ConnMan does not periodically try to autostart it. It is up to systemd or similar service management tool to autostart it. VPN === In order to compile pptp and l2tp VPN plugins, you need ppp development package. To run l2tp you will need - xl2tpd, http://www.xelerance.com/services/software/xl2tpd To run pptp you will need - pptp client, http://pptpclient.sourceforge.net Both l2tp and pptp also need pppd. OpenVPN ======= Up to version 2.2 of OpenVPN, pushing additional routes from the server will not always work. Some of the symptons are that additional routes will not be set by ConnMan if the uplink is a cellular network. While the same setup works well for a WiFi or ethernet uplink. GnuTLS ====== When using GnuTLS be aware that depending on the configuration of GnuTLS does either an lazy or eager initialization of an internal entropy pool using /dev/urandom. On eager initialization the loading of ConnMan will be delayed by the link loader until the entropy pool is filled. On smaller system this can easily delay the startup of ConnMan by several seconds (we had reports of 25 seconds and more delay). GnuTLS allows to switch back to lazy evaluation when the environment variable GNUTLS_NO_EXPLICIT_INIT. For more details please read the man page to gnutls_global_init(3). Online check ============ ConnMan tries to detect if it has Internet connection or not when a service is connected. If the online check succeeds the service enters Online state, if not it stays in Ready state. The online check is also used to detect whether ConnMan is behind a captive portal like when you are in hotel and need to pay for connectivity. The online check is done by trying to fetch status.html document from ipv4.connman.net (for IPv4 connectivity) and ipv6.connman.net (for IPv6 connectivity). The used URL looks like this http://ipv{4|6}.connman.net/online/status.html See connman.conf(5) for the EnableOnlineCheck option, if you need to disable the feature. During the online check procedure, ConnMan will temporarily install a host route to both the ipv4.connman.net and ipv6.connman.net so that the online check query can be directed via the correct network interface which the connected service is using. This host route is automatically removed when the online check is done. Note that the server expressly does not log any connection information, including IPv4/6 addresses of connecting clients. The server runtime logs cycle in RAM memory depending on amount of connections processed. ConnMan sends this very minimal information in http header when doing the online check request (example): Host: ipv4.connman.net User-Agent: ConnMan/1.23 wispr Connection: close Currently following information is returned from connman.net if the connection is successfull (200 OK http response code is returned): Server: nginx Date: Mon, 09 Jun 2014 09:25:42 GMT Content-Type: text/html Connection: close X-ConnMan-Status: online The X-ConnMan-Status field is used in portal detection, if it is missing ConnMan will call RequestBrowser method in net.connman.Agent dbus interface to handle the portal login if the portal does not support WISPr. See doc/agent-api.txt for more details. Information =========== Mailing list: connman@connman.net For additional information about the project visit ConnMan web site: https://01.org/connman http://www.connman.net You can report bugs at https://01.org/jira/browse/CM