xref: /openbmc/u-boot/drivers/net/sandbox.c (revision 76a503439e38be9d4fe365bdf87a6d0e74ea41c9)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2015 National Instruments
4  *
5  * (C) Copyright 2015
6  * Joe Hershberger <joe.hershberger@ni.com>
7  */
8 
9 #include <common.h>
10 #include <dm.h>
11 #include <malloc.h>
12 #include <net.h>
13 #include <asm/eth.h>
14 #include <asm/test.h>
15 
16 DECLARE_GLOBAL_DATA_PTR;
17 
18 static bool skip_timeout;
19 
20 /*
21  * sandbox_eth_disable_response()
22  *
23  * index - The alias index (also DM seq number)
24  * disable - If non-zero, ignore sent packets and don't send mock response
25  */
26 void sandbox_eth_disable_response(int index, bool disable)
27 {
28 	struct udevice *dev;
29 	struct eth_sandbox_priv *priv;
30 	int ret;
31 
32 	ret = uclass_get_device(UCLASS_ETH, index, &dev);
33 	if (ret)
34 		return;
35 
36 	priv = dev_get_priv(dev);
37 	priv->disabled = disable;
38 }
39 
40 /*
41  * sandbox_eth_skip_timeout()
42  *
43  * When the first packet read is attempted, fast-forward time
44  */
45 void sandbox_eth_skip_timeout(void)
46 {
47 	skip_timeout = true;
48 }
49 
50 /*
51  * sandbox_eth_arp_req_to_reply()
52  *
53  * Check for an arp request to be sent. If so, inject a reply
54  *
55  * returns 0 if injected, -EAGAIN if not
56  */
57 int sandbox_eth_arp_req_to_reply(struct udevice *dev, void *packet,
58 				 unsigned int len)
59 {
60 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
61 	struct ethernet_hdr *eth = packet;
62 	struct arp_hdr *arp;
63 	struct ethernet_hdr *eth_recv;
64 	struct arp_hdr *arp_recv;
65 
66 	if (ntohs(eth->et_protlen) != PROT_ARP)
67 		return -EAGAIN;
68 
69 	arp = packet + ETHER_HDR_SIZE;
70 
71 	if (ntohs(arp->ar_op) != ARPOP_REQUEST)
72 		return -EAGAIN;
73 
74 	/* store this as the assumed IP of the fake host */
75 	priv->fake_host_ipaddr = net_read_ip(&arp->ar_tpa);
76 
77 	/* Formulate a fake response */
78 	eth_recv = (void *)priv->recv_packet_buffer;
79 	memcpy(eth_recv->et_dest, eth->et_src, ARP_HLEN);
80 	memcpy(eth_recv->et_src, priv->fake_host_hwaddr, ARP_HLEN);
81 	eth_recv->et_protlen = htons(PROT_ARP);
82 
83 	arp_recv = (void *)eth_recv + ETHER_HDR_SIZE;
84 	arp_recv->ar_hrd = htons(ARP_ETHER);
85 	arp_recv->ar_pro = htons(PROT_IP);
86 	arp_recv->ar_hln = ARP_HLEN;
87 	arp_recv->ar_pln = ARP_PLEN;
88 	arp_recv->ar_op = htons(ARPOP_REPLY);
89 	memcpy(&arp_recv->ar_sha, priv->fake_host_hwaddr, ARP_HLEN);
90 	net_write_ip(&arp_recv->ar_spa, priv->fake_host_ipaddr);
91 	memcpy(&arp_recv->ar_tha, &arp->ar_sha, ARP_HLEN);
92 	net_copy_ip(&arp_recv->ar_tpa, &arp->ar_spa);
93 
94 	priv->recv_packet_length = ETHER_HDR_SIZE + ARP_HDR_SIZE;
95 
96 	return 0;
97 }
98 
99 /*
100  * sandbox_eth_ping_req_to_reply()
101  *
102  * Check for a ping request to be sent. If so, inject a reply
103  *
104  * returns 0 if injected, -EAGAIN if not
105  */
106 int sandbox_eth_ping_req_to_reply(struct udevice *dev, void *packet,
107 				  unsigned int len)
108 {
109 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
110 	struct ethernet_hdr *eth = packet;
111 	struct ip_udp_hdr *ip;
112 	struct icmp_hdr *icmp;
113 	struct ethernet_hdr *eth_recv;
114 	struct ip_udp_hdr *ipr;
115 	struct icmp_hdr *icmpr;
116 
117 	if (ntohs(eth->et_protlen) != PROT_IP)
118 		return -EAGAIN;
119 
120 	ip = packet + ETHER_HDR_SIZE;
121 
122 	if (ip->ip_p != IPPROTO_ICMP)
123 		return -EAGAIN;
124 
125 	icmp = (struct icmp_hdr *)&ip->udp_src;
126 
127 	if (icmp->type != ICMP_ECHO_REQUEST)
128 		return -EAGAIN;
129 
130 	/* reply to the ping */
131 	eth_recv = (void *)priv->recv_packet_buffer;
132 	memcpy(eth_recv, packet, len);
133 	ipr = (void *)eth_recv + ETHER_HDR_SIZE;
134 	icmpr = (struct icmp_hdr *)&ipr->udp_src;
135 	memcpy(eth_recv->et_dest, eth->et_src, ARP_HLEN);
136 	memcpy(eth_recv->et_src, priv->fake_host_hwaddr, ARP_HLEN);
137 	ipr->ip_sum = 0;
138 	ipr->ip_off = 0;
139 	net_copy_ip((void *)&ipr->ip_dst, &ip->ip_src);
140 	net_write_ip((void *)&ipr->ip_src, priv->fake_host_ipaddr);
141 	ipr->ip_sum = compute_ip_checksum(ipr, IP_HDR_SIZE);
142 
143 	icmpr->type = ICMP_ECHO_REPLY;
144 	icmpr->checksum = 0;
145 	icmpr->checksum = compute_ip_checksum(icmpr, ICMP_HDR_SIZE);
146 
147 	priv->recv_packet_length = len;
148 
149 	return 0;
150 }
151 
152 /*
153  * sb_default_handler()
154  *
155  * perform typical responses to simple ping
156  *
157  * dev - device pointer
158  * pkt - "sent" packet buffer
159  * len - length of packet
160  */
161 static int sb_default_handler(struct udevice *dev, void *packet,
162 			      unsigned int len)
163 {
164 	if (!sandbox_eth_arp_req_to_reply(dev, packet, len))
165 		return 0;
166 	if (!sandbox_eth_ping_req_to_reply(dev, packet, len))
167 		return 0;
168 
169 	return 0;
170 }
171 
172 /*
173  * sandbox_eth_set_tx_handler()
174  *
175  * Set a custom response to a packet being sent through the sandbox eth test
176  *	driver
177  *
178  * index - interface to set the handler for
179  * handler - The func ptr to call on send. If NULL, set to default handler
180  */
181 void sandbox_eth_set_tx_handler(int index, sandbox_eth_tx_hand_f *handler)
182 {
183 	struct udevice *dev;
184 	struct eth_sandbox_priv *priv;
185 	int ret;
186 
187 	ret = uclass_get_device(UCLASS_ETH, index, &dev);
188 	if (ret)
189 		return;
190 
191 	priv = dev_get_priv(dev);
192 	if (handler)
193 		priv->tx_handler = handler;
194 	else
195 		priv->tx_handler = sb_default_handler;
196 }
197 
198 static int sb_eth_start(struct udevice *dev)
199 {
200 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
201 
202 	debug("eth_sandbox: Start\n");
203 
204 	priv->recv_packet_buffer = net_rx_packets[0];
205 
206 	return 0;
207 }
208 
209 static int sb_eth_send(struct udevice *dev, void *packet, int length)
210 {
211 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
212 
213 	debug("eth_sandbox: Send packet %d\n", length);
214 
215 	if (priv->disabled)
216 		return 0;
217 
218 	return priv->tx_handler(dev, packet, length);
219 }
220 
221 static int sb_eth_recv(struct udevice *dev, int flags, uchar **packetp)
222 {
223 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
224 
225 	if (skip_timeout) {
226 		sandbox_timer_add_offset(11000UL);
227 		skip_timeout = false;
228 	}
229 
230 	if (priv->recv_packet_length) {
231 		int lcl_recv_packet_length = priv->recv_packet_length;
232 
233 		debug("eth_sandbox: received packet %d\n",
234 		      priv->recv_packet_length);
235 		priv->recv_packet_length = 0;
236 		*packetp = priv->recv_packet_buffer;
237 		return lcl_recv_packet_length;
238 	}
239 	return 0;
240 }
241 
242 static void sb_eth_stop(struct udevice *dev)
243 {
244 	debug("eth_sandbox: Stop\n");
245 }
246 
247 static int sb_eth_write_hwaddr(struct udevice *dev)
248 {
249 	struct eth_pdata *pdata = dev_get_platdata(dev);
250 
251 	debug("eth_sandbox %s: Write HW ADDR - %pM\n", dev->name,
252 	      pdata->enetaddr);
253 	return 0;
254 }
255 
256 static const struct eth_ops sb_eth_ops = {
257 	.start			= sb_eth_start,
258 	.send			= sb_eth_send,
259 	.recv			= sb_eth_recv,
260 	.stop			= sb_eth_stop,
261 	.write_hwaddr		= sb_eth_write_hwaddr,
262 };
263 
264 static int sb_eth_remove(struct udevice *dev)
265 {
266 	return 0;
267 }
268 
269 static int sb_eth_ofdata_to_platdata(struct udevice *dev)
270 {
271 	struct eth_pdata *pdata = dev_get_platdata(dev);
272 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
273 	const u8 *mac;
274 
275 	pdata->iobase = dev_read_addr(dev);
276 
277 	mac = dev_read_u8_array_ptr(dev, "fake-host-hwaddr", ARP_HLEN);
278 	if (!mac) {
279 		printf("'fake-host-hwaddr' is missing from the DT\n");
280 		return -EINVAL;
281 	}
282 	memcpy(priv->fake_host_hwaddr, mac, ARP_HLEN);
283 	priv->disabled = false;
284 	priv->tx_handler = sb_default_handler;
285 
286 	return 0;
287 }
288 
289 static const struct udevice_id sb_eth_ids[] = {
290 	{ .compatible = "sandbox,eth" },
291 	{ }
292 };
293 
294 U_BOOT_DRIVER(eth_sandbox) = {
295 	.name	= "eth_sandbox",
296 	.id	= UCLASS_ETH,
297 	.of_match = sb_eth_ids,
298 	.ofdata_to_platdata = sb_eth_ofdata_to_platdata,
299 	.remove	= sb_eth_remove,
300 	.ops	= &sb_eth_ops,
301 	.priv_auto_alloc_size = sizeof(struct eth_sandbox_priv),
302 	.platdata_auto_alloc_size = sizeof(struct eth_pdata),
303 };
304