2 * Copyright (C) 2015 Michael Brown <mbrown@fensystems.co.uk>.
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 (at your option) any later version.
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.
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
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.
24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
28 #include <ipxe/netdevice.h>
29 #include <ipxe/ethernet.h>
30 #include <ipxe/iobuf.h>
31 #include <ipxe/timer.h>
36 * Spanning Tree Protocol (STP)
40 /* Disambiguate the various error causes */
41 #define ENOTSUP_PROTOCOL __einfo_error ( EINFO_ENOTSUP_PROTOCOL )
42 #define EINFO_ENOTSUP_PROTOCOL \
43 __einfo_uniqify ( EINFO_ENOTSUP, 0x01, \
44 "Non-STP packet received" )
45 #define ENOTSUP_VERSION __einfo_error ( EINFO_ENOTSUP_VERSION )
46 #define EINFO_ENOTSUP_VERSION \
47 __einfo_uniqify ( EINFO_ENOTSUP, 0x01, \
48 "Legacy STP packet received" )
49 #define ENOTSUP_TYPE __einfo_error ( EINFO_ENOTSUP_TYPE )
50 #define EINFO_ENOTSUP_TYPE \
51 __einfo_uniqify ( EINFO_ENOTSUP, 0x01, \
52 "Non-RSTP packet received" )
55 * Process incoming STP packets
58 * @v netdev Network device
59 * @v ll_source Link-layer source address
60 * @v flags Packet flags
61 * @ret rc Return status code
63 static int stp_rx ( struct io_buffer *iobuf, struct net_device *netdev,
64 const void *ll_dest __unused,
65 const void *ll_source __unused,
66 unsigned int flags __unused ) {
72 if ( iob_len ( iobuf ) < sizeof ( *stp ) ) {
73 DBGC ( netdev, "STP %s received underlength packet (%zd "
74 "bytes):\n", netdev->name, iob_len ( iobuf ) );
75 DBGC_HDA ( netdev, 0, iobuf->data, iob_len ( iobuf ) );
81 /* Ignore non-RSTP packets */
82 if ( stp->protocol != htons ( STP_PROTOCOL ) ) {
83 DBGC ( netdev, "STP %s ignoring non-STP packet (protocol "
84 "%#04x)\n", netdev->name, ntohs ( stp->protocol ) );
85 rc = -ENOTSUP_PROTOCOL;
88 if ( stp->version < STP_VERSION_RSTP ) {
89 DBGC ( netdev, "STP %s received legacy STP packet (version "
90 "%#02x)\n", netdev->name, stp->version );
91 rc = -ENOTSUP_VERSION;
94 if ( stp->type != STP_TYPE_RSTP ) {
95 DBGC ( netdev, "STP %s received non-RSTP packet (type %#02x)\n",
96 netdev->name, stp->type );
101 /* Dump information */
102 DBGC2 ( netdev, "STP %s %s port %#04x flags %#02x hello %d delay %d\n",
103 netdev->name, eth_ntoa ( stp->sender.mac ), ntohs ( stp->port ),
104 stp->flags, ntohs ( stp->hello ), ntohs ( stp->delay ) );
106 /* Check if port is forwarding */
107 if ( ! ( stp->flags & STP_FL_FORWARDING ) ) {
108 /* Port is not forwarding: block link for two hello times */
109 DBGC ( netdev, "STP %s %s port %#04x flags %#02x is not "
111 netdev->name, eth_ntoa ( stp->sender.mac ),
112 ntohs ( stp->port ), stp->flags );
113 hello = ( ( ntohs ( stp->hello ) * TICKS_PER_SEC ) / 256 );
114 netdev_link_block ( netdev, ( hello * 2 ) );
120 if ( netdev_link_blocked ( netdev ) ) {
121 DBGC ( netdev, "STP %s %s port %#04x flags %#02x is "
123 netdev->name, eth_ntoa ( stp->sender.mac ),
124 ntohs ( stp->port ), stp->flags );
126 netdev_link_unblock ( netdev );
135 * Transcribe STP address
137 * @v net_addr STP address
138 * @ret string "<STP>"
140 * This operation is meaningless for the STP protocol.
142 static const char * stp_ntoa ( const void *net_addr __unused ) {
146 /** STP network protocol */
147 struct net_protocol stp_protocol __net_protocol = {
149 .net_proto = htons ( ETH_P_STP ),