1 /*
2 * Copyright (C) 2013 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 <string.h>
27 #include <byteswap.h>
28 #include <errno.h>
29 #include <ipxe/iobuf.h>
30 #include <ipxe/in.h>
31 #include <ipxe/tcpip.h>
32 #include <ipxe/ping.h>
33 #include <ipxe/crc32.h>
34 #include <ipxe/icmp.h>
35
36 /** @file
37 *
38 * ICMP protocol
39 *
40 */
41
42 /**
43 * Identify ICMP echo protocol
44 *
45 * @v st_family Address family
46 * @ret echo_protocol ICMP echo protocol, or NULL
47 */
icmp_echo_protocol(sa_family_t family)48 static struct icmp_echo_protocol * icmp_echo_protocol ( sa_family_t family ) {
49 struct icmp_echo_protocol *echo_protocol;
50
51 for_each_table_entry ( echo_protocol, ICMP_ECHO_PROTOCOLS ) {
52 if ( echo_protocol->family == family )
53 return echo_protocol;
54 }
55 return NULL;
56 }
57
58 /**
59 *
60 * Determine debugging colour for ICMP debug messages
61 *
62 * @v st_peer Peer address
63 * @ret col Debugging colour (for DBGC())
64 */
icmpcol(struct sockaddr_tcpip * st_peer)65 static uint32_t icmpcol ( struct sockaddr_tcpip *st_peer ) {
66
67 return crc32_le ( 0, st_peer, sizeof ( *st_peer ) );
68 }
69
70 /**
71 * Transmit ICMP echo packet
72 *
73 * @v iobuf I/O buffer
74 * @v st_dest Destination socket address
75 * @v echo_protocol ICMP echo protocol
76 * @ret rc Return status code
77 */
icmp_tx_echo(struct io_buffer * iobuf,struct sockaddr_tcpip * st_dest,struct icmp_echo_protocol * echo_protocol)78 static int icmp_tx_echo ( struct io_buffer *iobuf,
79 struct sockaddr_tcpip *st_dest,
80 struct icmp_echo_protocol *echo_protocol ) {
81 struct icmp_echo *echo = iobuf->data;
82 int rc;
83
84 /* Set ICMP type and (re)calculate checksum */
85 echo->icmp.chksum = 0;
86 echo->icmp.chksum = tcpip_chksum ( echo, iob_len ( iobuf ) );
87
88 /* Transmit packet */
89 if ( ( rc = tcpip_tx ( iobuf, echo_protocol->tcpip_protocol, NULL,
90 st_dest, NULL,
91 ( echo_protocol->net_checksum ?
92 &echo->icmp.chksum : NULL ) ) ) != 0 )
93 return rc;
94
95 return 0;
96 }
97
98 /**
99 * Transmit ICMP echo request
100 *
101 * @v iobuf I/O buffer
102 * @v st_dest Destination socket address
103 * @ret rc Return status code
104 */
icmp_tx_echo_request(struct io_buffer * iobuf,struct sockaddr_tcpip * st_dest)105 int icmp_tx_echo_request ( struct io_buffer *iobuf,
106 struct sockaddr_tcpip *st_dest ) {
107 struct icmp_echo *echo = iobuf->data;
108 struct icmp_echo_protocol *echo_protocol;
109 int rc;
110
111 /* Identify ICMP echo protocol */
112 echo_protocol = icmp_echo_protocol ( st_dest->st_family );
113 if ( ! echo_protocol ) {
114 DBGC ( icmpcol ( st_dest ), "ICMP TX echo request unknown "
115 "address family %d\n", st_dest->st_family );
116 free_iob ( iobuf );
117 return -ENOTSUP;
118 }
119
120 /* Set type */
121 echo->icmp.type = echo_protocol->request;
122
123 /* Transmit request */
124 DBGC ( icmpcol ( st_dest ), "ICMP TX echo request id %04x seq %04x\n",
125 ntohs ( echo->ident ), ntohs ( echo->sequence ) );
126 if ( ( rc = icmp_tx_echo ( iobuf, st_dest, echo_protocol ) ) != 0 )
127 return rc;
128
129 return 0;
130 }
131
132 /**
133 * Transmit ICMP echo reply
134 *
135 * @v iobuf I/O buffer
136 * @v st_dest Destination socket address
137 * @ret rc Return status code
138 */
icmp_tx_echo_reply(struct io_buffer * iobuf,struct sockaddr_tcpip * st_dest,struct icmp_echo_protocol * echo_protocol)139 static int icmp_tx_echo_reply ( struct io_buffer *iobuf,
140 struct sockaddr_tcpip *st_dest,
141 struct icmp_echo_protocol *echo_protocol ) {
142 struct icmp_echo *echo = iobuf->data;
143 int rc;
144
145 /* Set type */
146 echo->icmp.type = echo_protocol->reply;
147
148 /* Transmit reply */
149 DBGC ( icmpcol ( st_dest ), "ICMP TX echo reply id %04x seq %04x\n",
150 ntohs ( echo->ident ), ntohs ( echo->sequence ) );
151 if ( ( rc = icmp_tx_echo ( iobuf, st_dest, echo_protocol ) ) != 0 )
152 return rc;
153
154 return 0;
155 }
156
157 /**
158 * Process a received ICMP echo request
159 *
160 * @v iobuf I/O buffer
161 * @v st_src Source socket address
162 * @v echo_protocol ICMP echo protocol
163 * @ret rc Return status code
164 */
icmp_rx_echo_request(struct io_buffer * iobuf,struct sockaddr_tcpip * st_src,struct icmp_echo_protocol * echo_protocol)165 int icmp_rx_echo_request ( struct io_buffer *iobuf,
166 struct sockaddr_tcpip *st_src,
167 struct icmp_echo_protocol *echo_protocol ) {
168 struct icmp_echo *echo = iobuf->data;
169 int rc;
170
171 /* Sanity check */
172 if ( iob_len ( iobuf ) < sizeof ( *echo ) ) {
173 DBGC ( icmpcol ( st_src ), "ICMP RX echo request too short at "
174 "%zd bytes (min %zd bytes)\n",
175 iob_len ( iobuf ), sizeof ( *echo ) );
176 free_iob ( iobuf );
177 return -EINVAL;
178 }
179 DBGC ( icmpcol ( st_src ), "ICMP RX echo request id %04x seq %04x\n",
180 ntohs ( echo->ident ), ntohs ( echo->sequence ) );
181
182 /* Transmit echo reply */
183 if ( ( rc = icmp_tx_echo_reply ( iobuf, st_src, echo_protocol ) ) != 0 )
184 return rc;
185
186 return 0;
187 }
188
189 /**
190 * Process a received ICMP echo request
191 *
192 * @v iobuf I/O buffer
193 * @v st_src Source socket address
194 * @ret rc Return status code
195 */
icmp_rx_echo_reply(struct io_buffer * iobuf,struct sockaddr_tcpip * st_src)196 int icmp_rx_echo_reply ( struct io_buffer *iobuf,
197 struct sockaddr_tcpip *st_src ) {
198 struct icmp_echo *echo = iobuf->data;
199 int rc;
200
201 /* Sanity check */
202 if ( iob_len ( iobuf ) < sizeof ( *echo ) ) {
203 DBGC ( icmpcol ( st_src ), "ICMP RX echo reply too short at "
204 "%zd bytes (min %zd bytes)\n",
205 iob_len ( iobuf ), sizeof ( *echo ) );
206 free_iob ( iobuf );
207 return -EINVAL;
208 }
209 DBGC ( icmpcol ( st_src ), "ICMP RX echo reply id %04x seq %04x\n",
210 ntohs ( echo->ident ), ntohs ( echo->sequence ) );
211
212 /* Deliver to ping protocol */
213 if ( ( rc = ping_rx ( iobuf, st_src ) ) != 0 )
214 return rc;
215
216 return 0;
217 }
218
219 /**
220 * Receive ping reply (when no ping protocol is present)
221 *
222 * @v iobuf I/O buffer
223 * @v st_src Source socket address
224 * @ret rc Return status code
225 */
ping_rx(struct io_buffer * iobuf,struct sockaddr_tcpip * st_src __unused)226 __weak int ping_rx ( struct io_buffer *iobuf,
227 struct sockaddr_tcpip *st_src __unused ) {
228 free_iob ( iobuf );
229 return 0;
230 }
231