iPXE
eapol.c
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1 /*
2  * Copyright (C) 2021 Michael Brown <mbrown@fensystems.co.uk>.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License as
6  * published by the Free Software Foundation; either version 2 of the
7  * License, or any later version.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17  * 02110-1301, USA.
18  *
19  * You can also choose to distribute this program under the terms of
20  * the Unmodified Binary Distribution Licence (as given in the file
21  * COPYING.UBDL), provided that you have satisfied its requirements.
22  */
23 
24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
25 
26 #include <assert.h>
27 #include <errno.h>
28 #include <byteswap.h>
29 #include <ipxe/iobuf.h>
30 #include <ipxe/if_ether.h>
31 #include <ipxe/netdevice.h>
32 #include <ipxe/eap.h>
33 #include <ipxe/eapol.h>
34 
35 /** @file
36  *
37  * Extensible Authentication Protocol over LAN (EAPoL)
38  *
39  */
40 
41 /**
42  * Process EAPoL packet
43  *
44  * @v iobuf I/O buffer
45  * @v netdev Network device
46  * @v ll_dest Link-layer destination address
47  * @v ll_source Link-layer source address
48  * @v flags Packet flags
49  * @ret rc Return status code
50  */
51 static int eapol_rx ( struct io_buffer *iobuf, struct net_device *netdev,
52  const void *ll_dest __unused, const void *ll_source,
53  unsigned int flags __unused ) {
54  struct eapol_header *eapol;
55  struct eapol_handler *handler;
56  size_t remaining;
57  size_t len;
58  int rc;
59 
60  /* Sanity checks */
61  if ( iob_len ( iobuf ) < sizeof ( *eapol ) ) {
62  DBGC ( netdev, "EAPOL %s underlength header:\n",
63  netdev->name );
64  DBGC_HDA ( netdev, 0, iobuf->data, iob_len ( iobuf ) );
65  rc = -EINVAL;
66  goto drop;
67  }
68  eapol = iobuf->data;
69  remaining = ( iob_len ( iobuf ) - sizeof ( *eapol ) );
70  len = ntohs ( eapol->len );
71  if ( len > remaining ) {
72  DBGC ( netdev, "EAPOL %s v%d type %d len %zd underlength "
73  "payload:\n", netdev->name, eapol->version,
74  eapol->type, len );
75  DBGC_HDA ( netdev, 0, iobuf->data, iob_len ( iobuf ) );
76  rc = -EINVAL;
77  goto drop;
78  }
79 
80  /* Strip any trailing padding */
81  iob_unput ( iobuf, ( len - remaining ) );
82 
83  /* Handle according to type */
85  if ( handler->type == eapol->type ) {
86  return handler->rx ( iob_disown ( iobuf ) , netdev,
87  ll_source );
88  }
89  }
90  rc = -ENOTSUP;
91  DBGC ( netdev, "EAPOL %s v%d type %d unsupported\n",
92  netdev->name, eapol->version, eapol->type );
93  DBGC_HDA ( netdev, 0, iobuf->data, iob_len ( iobuf ) );
94 
95  drop:
96  free_iob ( iobuf );
97  return rc;
98 }
99 
100 /** EAPoL protocol */
101 struct net_protocol eapol_protocol __net_protocol = {
102  .name = "EAPOL",
103  .net_proto = htons ( ETH_P_EAPOL ),
104  .rx = eapol_rx,
105 };
106 
107 /**
108  * Process EAPoL-encapsulated EAP packet
109  *
110  * @v netdev Network device
111  * @v ll_source Link-layer source address
112  * @ret rc Return status code
113  */
114 static int eapol_eap_rx ( struct io_buffer *iobuf, struct net_device *netdev,
115  const void *ll_source __unused ) {
116  struct eapol_header *eapol;
117  int rc;
118 
119  /* Sanity check */
120  assert ( iob_len ( iobuf ) >= sizeof ( *eapol ) );
121 
122  /* Strip EAPoL header */
123  eapol = iob_pull ( iobuf, sizeof ( *eapol ) );
124 
125  /* Process EAP packet */
126  if ( ( rc = eap_rx ( netdev, iobuf->data, iob_len ( iobuf ) ) ) != 0 ) {
127  DBGC ( netdev, "EAPOL %s v%d EAP failed: %s\n",
128  netdev->name, eapol->version, strerror ( rc ) );
129  goto drop;
130  }
131 
132  drop:
133  free_iob ( iobuf );
134  return rc;
135 }
136 
137 /** EAPoL handler for EAP packets */
138 struct eapol_handler eapol_eap __eapol_handler = {
139  .type = EAPOL_TYPE_EAP,
140  .rx = eapol_eap_rx,
141 };
#define iob_pull(iobuf, len)
Definition: iobuf.h:102
uint16_t len
Payload length.
Definition: eapol.h:23
#define EINVAL
Invalid argument.
Definition: errno.h:428
struct arbelprm_rc_send_wqe rc
Definition: arbel.h:14
const char * name
Protocol name.
Definition: netdevice.h:66
int eap_rx(struct net_device *netdev, const void *data, size_t len)
Handle EAP packet.
Definition: eap.c:118
struct net_protocol eapol_protocol __net_protocol
EAPoL protocol.
Definition: eapol.c:101
Error codes.
FILE_LICENCE(GPL2_OR_LATER_OR_UBDL)
I/O buffers.
void free_iob(struct io_buffer *iobuf)
Free I/O buffer.
Definition: iobuf.c:146
#define DBGC(...)
Definition: compiler.h:505
static int eapol_rx(struct io_buffer *iobuf, struct net_device *netdev, const void *ll_dest __unused, const void *ll_source, unsigned int flags __unused)
Process EAPoL packet.
Definition: eapol.c:51
#define ntohs(value)
Definition: byteswap.h:136
#define EAPOL_HANDLERS
EAPoL handler table.
Definition: eapol.h:54
#define ENOTSUP
Operation not supported.
Definition: errno.h:589
#define iob_disown(iobuf)
Disown an I/O buffer.
Definition: iobuf.h:212
EAPoL header.
Definition: eapol.h:17
Assertions.
assert((readw(&hdr->flags) &(GTF_reading|GTF_writing))==0)
#define DBGC_HDA(...)
Definition: compiler.h:506
static struct net_device * netdev
Definition: gdbudp.c:52
Extensible Authentication Protocol over LAN (EAPoL)
An EAPoL handler.
Definition: eapol.h:36
#define iob_unput(iobuf, len)
Definition: iobuf.h:135
char * strerror(int errno)
Retrieve string representation of error number.
Definition: strerror.c:78
static size_t iob_len(struct io_buffer *iobuf)
Calculate length of data in an I/O buffer.
Definition: iobuf.h:155
#define for_each_table_entry(pointer, table)
Iterate through all entries within a linker table.
Definition: tables.h:358
int(* rx)(struct io_buffer *iobuf, struct net_device *netdev, const void *ll_source)
Process received packet.
Definition: eapol.h:49
A network device.
Definition: netdevice.h:352
#define EAPOL_TYPE_EAP
EAPoL-encapsulated EAP packets.
Definition: eapol.h:30
uint8_t type
Type.
Definition: eapol.h:21
A network-layer protocol.
Definition: netdevice.h:64
Network device management.
#define __unused
Declare a variable or data structure as unused.
Definition: compiler.h:573
static int eapol_eap_rx(struct io_buffer *iobuf, struct net_device *netdev, const void *ll_source __unused)
Process EAPoL-encapsulated EAP packet.
Definition: eapol.c:114
char name[NETDEV_NAME_LEN]
Name of this network device.
Definition: netdevice.h:362
uint32_t len
Length.
Definition: ena.h:14
void * data
Start of data.
Definition: iobuf.h:48
uint8_t version
Version.
Definition: eapol.h:19
#define ETH_P_EAPOL
Definition: if_ether.h:24
uint8_t type
Type.
Definition: eapol.h:38
#define htons(value)
Definition: byteswap.h:135
struct eapol_handler eapol_eap __eapol_handler
EAPoL handler for EAP packets.
Definition: eapol.c:138
Extensible Authentication Protocol.
A persistent I/O buffer.
Definition: iobuf.h:33
uint8_t flags
Flags.
Definition: ena.h:18