/** \page ctrl_iface_page Control interface %wpa_supplicant implements a control interface that can be used by external programs to control the operations of the %wpa_supplicant daemon and to get status information and event notifications. There is a small C library, in a form of a single C file, wpa_ctrl.c, that provides helper functions to facilitate the use of the control interface. External programs can link this file into them and then use the library functions documented in wpa_ctrl.h to interact with %wpa_supplicant. This library can also be used with C++. wpa_cli.c and wpa_gui are example programs using this library. There are multiple mechanisms for inter-process communication. For example, Linux version of %wpa_supplicant is using UNIX domain sockets for the control interface and Windows version UDP sockets. The use of the functions defined in wpa_ctrl.h can be used to hide the details of the used IPC from external programs. \section using_ctrl_iface Using the control interface External programs, e.g., a GUI or a configuration utility, that need to communicate with %wpa_supplicant should link in wpa_ctrl.c. This allows them to use helper functions to open connection to the control interface with wpa_ctrl_open() and to send commands with wpa_ctrl_request(). %wpa_supplicant uses the control interface for two types of communication: commands and unsolicited event messages. Commands are a pair of messages, a request from the external program and a response from %wpa_supplicant. These can be executed using wpa_ctrl_request(). Unsolicited event messages are sent by %wpa_supplicant to the control interface connection without specific request from the external program for receiving each message. However, the external program needs to attach to the control interface with wpa_ctrl_attach() to receive these unsolicited messages. If the control interface connection is used both for commands and unsolicited event messages, there is potential for receiving an unsolicited message between the command request and response. wpa_ctrl_request() caller will need to supply a callback, msg_cb, for processing these messages. Often it is easier to open two control interface connections by calling wpa_ctrl_open() twice and then use one of the connections for commands and the other one for unsolicited messages. This way command request/response pairs will not be broken by unsolicited messages. wpa_cli is an example of how to use only one connection for both purposes and wpa_gui demonstrates how to use two separate connections. Once the control interface connection is not needed anymore, it should be closed by calling wpa_ctrl_close(). If the connection was used for unsolicited event messages, it should be first detached by calling wpa_ctrl_detach(). \section ctrl_iface_cmds Control interface commands Following commands can be used with wpa_ctrl_request(): \subsection ctrl_iface_PING PING This command can be used to test whether %wpa_supplicant is replying to the control interface commands. The expected reply is \c PONG if the connection is open and %wpa_supplicant is processing commands. \subsection ctrl_iface_MIB MIB Request a list of MIB variables (dot1x, dot11). The output is a text block with each line in \c variable=value format. For example: \verbatim dot11RSNAOptionImplemented=TRUE dot11RSNAPreauthenticationImplemented=TRUE dot11RSNAEnabled=FALSE dot11RSNAPreauthenticationEnabled=FALSE dot11RSNAConfigVersion=1 dot11RSNAConfigPairwiseKeysSupported=5 dot11RSNAConfigGroupCipherSize=128 dot11RSNAConfigPMKLifetime=43200 dot11RSNAConfigPMKReauthThreshold=70 dot11RSNAConfigNumberOfPTKSAReplayCounters=1 dot11RSNAConfigSATimeout=60 dot11RSNAAuthenticationSuiteSelected=00-50-f2-2 dot11RSNAPairwiseCipherSelected=00-50-f2-4 dot11RSNAGroupCipherSelected=00-50-f2-4 dot11RSNAPMKIDUsed= dot11RSNAAuthenticationSuiteRequested=00-50-f2-2 dot11RSNAPairwiseCipherRequested=00-50-f2-4 dot11RSNAGroupCipherRequested=00-50-f2-4 dot11RSNAConfigNumberOfGTKSAReplayCounters=0 dot11RSNA4WayHandshakeFailures=0 dot1xSuppPaeState=5 dot1xSuppHeldPeriod=60 dot1xSuppAuthPeriod=30 dot1xSuppStartPeriod=30 dot1xSuppMaxStart=3 dot1xSuppSuppControlledPortStatus=Authorized dot1xSuppBackendPaeState=2 dot1xSuppEapolFramesRx=0 dot1xSuppEapolFramesTx=440 dot1xSuppEapolStartFramesTx=2 dot1xSuppEapolLogoffFramesTx=0 dot1xSuppEapolRespFramesTx=0 dot1xSuppEapolReqIdFramesRx=0 dot1xSuppEapolReqFramesRx=0 dot1xSuppInvalidEapolFramesRx=0 dot1xSuppEapLengthErrorFramesRx=0 dot1xSuppLastEapolFrameVersion=0 dot1xSuppLastEapolFrameSource=00:00:00:00:00:00 \endverbatim \subsection ctrl_iface_STATUS STATUS Request current WPA/EAPOL/EAP status information. The output is a text block with each line in \c variable=value format. For example: \verbatim bssid=02:00:01:02:03:04 ssid=test network pairwise_cipher=CCMP group_cipher=CCMP key_mgmt=WPA-PSK wpa_state=COMPLETED ip_address=192.168.1.21 Supplicant PAE state=AUTHENTICATED suppPortStatus=Authorized EAP state=SUCCESS \endverbatim \subsection ctrl_iface_STATUS-VERBOSE STATUS-VERBOSE Same as STATUS, but with more verbosity (i.e., more \c variable=value pairs). \verbatim bssid=02:00:01:02:03:04 ssid=test network id=0 pairwise_cipher=CCMP group_cipher=CCMP key_mgmt=WPA-PSK wpa_state=COMPLETED ip_address=192.168.1.21 Supplicant PAE state=AUTHENTICATED suppPortStatus=Authorized heldPeriod=60 authPeriod=30 startPeriod=30 maxStart=3 portControl=Auto Supplicant Backend state=IDLE EAP state=SUCCESS reqMethod=0 methodState=NONE decision=COND_SUCC ClientTimeout=60 \endverbatim \subsection ctrl_iface_PMKSA PMKSA Show PMKSA cache \verbatim Index / AA / PMKID / expiration (in seconds) / opportunistic 1 / 02:00:01:02:03:04 / 000102030405060708090a0b0c0d0e0f / 41362 / 0 2 / 02:00:01:33:55:77 / 928389281928383b34afb34ba4212345 / 362 / 1 \endverbatim \subsection ctrl_iface_SET SET Set variables: - EAPOL::heldPeriod - EAPOL::authPeriod - EAPOL::startPeriod - EAPOL::maxStart - dot11RSNAConfigPMKLifetime - dot11RSNAConfigPMKReauthThreshold - dot11RSNAConfigSATimeout Example command: \verbatim SET EAPOL::heldPeriod 45 \endverbatim \subsection ctrl_iface_LOGON LOGON IEEE 802.1X EAPOL state machine logon. \subsection ctrl_iface_LOGOFF LOGOFF IEEE 802.1X EAPOL state machine logoff. \subsection ctrl_iface_REASSOCIATE REASSOCIATE Force reassociation. \subsection ctrl_iface_RECONNECT RECONNECT Connect if disconnected (i.e., like \c REASSOCIATE, but only connect if in disconnected state). \subsection ctrl_iface_PREAUTH PREAUTH Start pre-authentication with the given BSSID. \subsection ctrl_iface_ATTACH ATTACH Attach the connection as a monitor for unsolicited events. This can be done with wpa_ctrl_attach(). \subsection ctrl_iface_DETACH DETACH Detach the connection as a monitor for unsolicited events. This can be done with wpa_ctrl_detach(). \subsection ctrl_iface_LEVEL LEVEL Change debug level. \subsection ctrl_iface_RECONFIGURE RECONFIGURE Force %wpa_supplicant to re-read its configuration data. \subsection ctrl_iface_TERMINATE TERMINATE Terminate %wpa_supplicant process. \subsection ctrl_iface_BSSID BSSID Set preferred BSSID for a network. Network id can be received from the \c LIST_NETWORKS command output. \subsection ctrl_iface_LIST_NETWORKS LIST_NETWORKS List configured networks. \verbatim network id / ssid / bssid / flags 0 example network any [CURRENT] \endverbatim (note: fields are separated with tabs) \subsection ctrl_iface_DISCONNECT DISCONNECT Disconnect and wait for \c REASSOCIATE or \c RECONNECT command before connecting. \subsection ctrl_iface_SCAN SCAN Request a new BSS scan. \subsection ctrl_iface_SCAN_RESULTS SCAN_RESULTS Get the latest scan results. \verbatim bssid / frequency / signal level / flags / ssid 00:09:5b:95:e0:4e 2412 208 [WPA-PSK-CCMP] jkm private 02:55:24:33:77:a3 2462 187 [WPA-PSK-TKIP] testing 00:09:5b:95:e0:4f 2412 209 jkm guest \endverbatim (note: fields are separated with tabs) \subsection ctrl_iface_BSS BSS Get detailed per-BSS scan results. \c BSS command can be used to iterate through scan results one BSS at a time and to fetch all information from the found BSSes. This provides access to the same data that is available through \c SCAN_RESULTS but in a way that avoids problems with large number of scan results not fitting in the ctrl_iface messages. There are two options for selecting the BSS with the \c BSS command: "BSS " requests information for the BSS identified by the index (0 .. size-1) in the scan results table and "BSS " requests information for the given BSS (based on BSSID in 00:01:02:03:04:05 format). BSS information is presented in following format. Please note that new fields may be added to this field=value data, so the ctrl_iface user should be prepared to ignore values it does not understand. \verbatim bssid=00:09:5b:95:e0:4e freq=2412 beacon_int=0 capabilities=0x0011 qual=51 noise=161 level=212 tsf=0000000000000000 ie=000b6a6b6d2070726976617465010180dd180050f20101000050f20401000050f20401000050f2020000 ssid=jkm private \endverbatim \subsection ctrl_iface_SELECT_NETWORK SELECT_NETWORK Select a network (disable others). Network id can be received from the \c LIST_NETWORKS command output. \subsection ctrl_iface_ENABLE_NETWORK ENABLE_NETWORK Enable a network. Network id can be received from the \c LIST_NETWORKS command output. Special network id \c all can be used to enable all network. \subsection ctrl_iface_DISABLE_NETWORK DISABLE_NETWORK Disable a network. Network id can be received from the \c LIST_NETWORKS command output. Special network id \c all can be used to disable all network. \subsection ctrl_iface_ADD_NETWORK ADD_NETWORK Add a new network. This command creates a new network with empty configuration. The new network is disabled and once it has been configured it can be enabled with \c ENABLE_NETWORK command. \c ADD_NETWORK returns the network id of the new network or FAIL on failure. \subsection ctrl_iface_REMOVE_NETWORK REMOVE_NETWORK Remove a network. Network id can be received from the \c LIST_NETWORKS command output. Special network id \c all can be used to remove all network. \subsection ctrl_iface_SET_NETWORK SET_NETWORK Set network variables. Network id can be received from the \c LIST_NETWORKS command output. This command uses the same variables and data formats as the configuration file. See example wpa_supplicant.conf for more details. - ssid (network name, SSID) - psk (WPA passphrase or pre-shared key) - key_mgmt (key management protocol) - identity (EAP identity) - password (EAP password) - ... \subsection ctrl_iface_GET_NETWORK GET_NETWORK Get network variables. Network id can be received from the \c LIST_NETWORKS command output. \subsection ctrl_iface_SAVE_CONFIG SAVE_CONFIG Save the current configuration. \section ctrl_iface_interactive Interactive requests If %wpa_supplicant needs additional information during authentication (e.g., password), it will use a specific prefix, \c CTRL-REQ- (\a WPA_CTRL_REQ macro) in an unsolicited event message. An external program, e.g., a GUI, can provide such information by using \c CTRL-RSP- (\a WPA_CTRL_RSP macro) prefix in a command with matching field name. The following fields can be requested in this way from the user: - IDENTITY (EAP identity/user name) - PASSWORD (EAP password) - NEW_PASSWORD (New password if the server is requesting password change) - PIN (PIN code for accessing a SIM or smartcard) - OTP (one-time password; like password, but the value is used only once) - PASSPHRASE (passphrase for a private key file) \verbatim CTRL-REQ--- CTRL-RSP--- \endverbatim For example, request from %wpa_supplicant: \verbatim CTRL-REQ-PASSWORD-1-Password needed for SSID test-network \endverbatim And a matching reply from the GUI: \verbatim CTRL-RSP-PASSWORD-1-secret \endverbatim \subsection ctrl_iface_GET_CAPABILITY GET_CAPABILITY