iPXE
eapol.h
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00001 /*
00002  * Copyright (c) 2009 Joshua Oreman <oremanj@rwcr.net>.
00003  *
00004  * This program is free software; you can redistribute it and/or
00005  * modify it under the terms of the GNU General Public License as
00006  * published by the Free Software Foundation; either version 2 of the
00007  * License, or any later version.
00008  *
00009  * This program is distributed in the hope that it will be useful, but
00010  * WITHOUT ANY WARRANTY; without even the implied warranty of
00011  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00012  * General Public License for more details.
00013  *
00014  * You should have received a copy of the GNU General Public License
00015  * along with this program; if not, write to the Free Software
00016  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
00017  * 02110-1301, USA.
00018  */
00019 
00020 #ifndef _IPXE_EAPOL_H
00021 #define _IPXE_EAPOL_H
00022 
00023 /** @file
00024  *
00025  * Definitions for EAPOL (Extensible Authentication Protocol over
00026  * LANs) frames. Definitions for the packets usually encapsulated in
00027  * them are elsewhere.
00028  */
00029 
00030 #include <ipxe/tables.h>
00031 #include <stdint.h>
00032 
00033 FILE_LICENCE ( GPL2_OR_LATER );
00034 
00035 
00036 /**
00037  * @defgroup eapol_type EAPOL archetype identifiers
00038  * @{
00039  */
00040 #define EAPOL_TYPE_EAP          0 /**< EAP authentication handshake packet */
00041 #define EAPOL_TYPE_START        1 /**< Request by Peer to begin (no data) */
00042 #define EAPOL_TYPE_LOGOFF       2 /**< Request by Peer to terminate (no data) */
00043 #define EAPOL_TYPE_KEY          3 /**< EAPOL-Key packet */
00044 /** @} */
00045 
00046 /** Expected EAPOL version field value
00047  *
00048  * Version 2 is often seen and has no format differences from version 1;
00049  * however, many older APs will completely drop version-2 packets, so
00050  * we advertise ourselves as version 1.
00051  */
00052 #define EAPOL_THIS_VERSION      1
00053 
00054 /** Length of an EAPOL frame header */
00055 #define EAPOL_HDR_LEN           4
00056 
00057 /** An EAPOL frame
00058  *
00059  * This may encapsulate an eap_pkt, an eapol_key_pkt, or a Start or
00060  * Logoff request with no data attached. It is transmitted directly in
00061  * an Ethernet frame, with no IP packet header.
00062  */
00063 struct eapol_frame
00064 {
00065         /** EAPOL version identifier, always 1 */
00066         u8 version;
00067 
00068         /** EAPOL archetype identifier indicating format of payload */
00069         u8 type;
00070 
00071         /** Length of payload, in network byte order */
00072         u16 length;
00073 
00074         /** Payload, if @a type is EAP or EAPOL-Key */
00075         u8 data[0];
00076 } __attribute__ (( packed ));
00077 
00078 
00079 /** An EAPOL frame type handler
00080  *
00081  * Normally there will be at most two of these, one for EAP and one
00082  * for EAPOL-Key frames. The EAPOL interface code handles Start and
00083  * Logoff directly.
00084  */
00085 struct eapol_handler
00086 {
00087         /** EAPOL archetype identifier for payload this handler will handle */
00088         u8 type;
00089 
00090         /** Receive EAPOL-encapsulated packet of specified type
00091          *
00092          * @v iob       I/O buffer containing packet payload
00093          * @v netdev    Network device from which packet was received
00094          * @V ll_dest   Destination link-layer address
00095          * @v ll_source Source link-layer address
00096          * @ret rc      Return status code
00097          *
00098          * The I/O buffer will have the EAPOL header pulled off it, so
00099          * @c iob->data points to the first byte of the payload.
00100          *
00101          * This function takes ownership of the I/O buffer passed to it.
00102          */
00103         int ( * rx ) ( struct io_buffer *iob, struct net_device *netdev,
00104                        const void *ll_dest, const void *ll_source );
00105 };
00106 
00107 #define EAPOL_HANDLERS  __table ( struct eapol_handler, "eapol_handlers" )
00108 #define __eapol_handler __table_entry ( EAPOL_HANDLERS, 01 )
00109 
00110 
00111 extern struct net_protocol eapol_protocol __net_protocol;
00112 
00113 
00114 #endif /* _IPXE_EAPOL_H */