xref: /openbmc/u-boot/drivers/net/sandbox.c (revision 9cbe5972c3c00e974482181cd4062d9229a9b7d5)
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 	/* Don't allow the buffer to overrun */
75 	if (priv->recv_packets >= PKTBUFSRX)
76 		return 0;
77 
78 	/* store this as the assumed IP of the fake host */
79 	priv->fake_host_ipaddr = net_read_ip(&arp->ar_tpa);
80 
81 	/* Formulate a fake response */
82 	eth_recv = (void *)priv->recv_packet_buffer[priv->recv_packets];
83 	memcpy(eth_recv->et_dest, eth->et_src, ARP_HLEN);
84 	memcpy(eth_recv->et_src, priv->fake_host_hwaddr, ARP_HLEN);
85 	eth_recv->et_protlen = htons(PROT_ARP);
86 
87 	arp_recv = (void *)eth_recv + ETHER_HDR_SIZE;
88 	arp_recv->ar_hrd = htons(ARP_ETHER);
89 	arp_recv->ar_pro = htons(PROT_IP);
90 	arp_recv->ar_hln = ARP_HLEN;
91 	arp_recv->ar_pln = ARP_PLEN;
92 	arp_recv->ar_op = htons(ARPOP_REPLY);
93 	memcpy(&arp_recv->ar_sha, priv->fake_host_hwaddr, ARP_HLEN);
94 	net_write_ip(&arp_recv->ar_spa, priv->fake_host_ipaddr);
95 	memcpy(&arp_recv->ar_tha, &arp->ar_sha, ARP_HLEN);
96 	net_copy_ip(&arp_recv->ar_tpa, &arp->ar_spa);
97 
98 	priv->recv_packet_length[priv->recv_packets] =
99 		ETHER_HDR_SIZE + ARP_HDR_SIZE;
100 	++priv->recv_packets;
101 
102 	return 0;
103 }
104 
105 /*
106  * sandbox_eth_ping_req_to_reply()
107  *
108  * Check for a ping request to be sent. If so, inject a reply
109  *
110  * returns 0 if injected, -EAGAIN if not
111  */
112 int sandbox_eth_ping_req_to_reply(struct udevice *dev, void *packet,
113 				  unsigned int len)
114 {
115 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
116 	struct ethernet_hdr *eth = packet;
117 	struct ip_udp_hdr *ip;
118 	struct icmp_hdr *icmp;
119 	struct ethernet_hdr *eth_recv;
120 	struct ip_udp_hdr *ipr;
121 	struct icmp_hdr *icmpr;
122 
123 	if (ntohs(eth->et_protlen) != PROT_IP)
124 		return -EAGAIN;
125 
126 	ip = packet + ETHER_HDR_SIZE;
127 
128 	if (ip->ip_p != IPPROTO_ICMP)
129 		return -EAGAIN;
130 
131 	icmp = (struct icmp_hdr *)&ip->udp_src;
132 
133 	if (icmp->type != ICMP_ECHO_REQUEST)
134 		return -EAGAIN;
135 
136 	/* Don't allow the buffer to overrun */
137 	if (priv->recv_packets >= PKTBUFSRX)
138 		return 0;
139 
140 	/* reply to the ping */
141 	eth_recv = (void *)priv->recv_packet_buffer[priv->recv_packets];
142 	memcpy(eth_recv, packet, len);
143 	ipr = (void *)eth_recv + ETHER_HDR_SIZE;
144 	icmpr = (struct icmp_hdr *)&ipr->udp_src;
145 	memcpy(eth_recv->et_dest, eth->et_src, ARP_HLEN);
146 	memcpy(eth_recv->et_src, priv->fake_host_hwaddr, ARP_HLEN);
147 	ipr->ip_sum = 0;
148 	ipr->ip_off = 0;
149 	net_copy_ip((void *)&ipr->ip_dst, &ip->ip_src);
150 	net_write_ip((void *)&ipr->ip_src, priv->fake_host_ipaddr);
151 	ipr->ip_sum = compute_ip_checksum(ipr, IP_HDR_SIZE);
152 
153 	icmpr->type = ICMP_ECHO_REPLY;
154 	icmpr->checksum = 0;
155 	icmpr->checksum = compute_ip_checksum(icmpr, ICMP_HDR_SIZE);
156 
157 	priv->recv_packet_length[priv->recv_packets] = len;
158 	++priv->recv_packets;
159 
160 	return 0;
161 }
162 
163 /*
164  * sb_default_handler()
165  *
166  * perform typical responses to simple ping
167  *
168  * dev - device pointer
169  * pkt - "sent" packet buffer
170  * len - length of packet
171  */
172 static int sb_default_handler(struct udevice *dev, void *packet,
173 			      unsigned int len)
174 {
175 	if (!sandbox_eth_arp_req_to_reply(dev, packet, len))
176 		return 0;
177 	if (!sandbox_eth_ping_req_to_reply(dev, packet, len))
178 		return 0;
179 
180 	return 0;
181 }
182 
183 /*
184  * sandbox_eth_set_tx_handler()
185  *
186  * Set a custom response to a packet being sent through the sandbox eth test
187  *	driver
188  *
189  * index - interface to set the handler for
190  * handler - The func ptr to call on send. If NULL, set to default handler
191  */
192 void sandbox_eth_set_tx_handler(int index, sandbox_eth_tx_hand_f *handler)
193 {
194 	struct udevice *dev;
195 	struct eth_sandbox_priv *priv;
196 	int ret;
197 
198 	ret = uclass_get_device(UCLASS_ETH, index, &dev);
199 	if (ret)
200 		return;
201 
202 	priv = dev_get_priv(dev);
203 	if (handler)
204 		priv->tx_handler = handler;
205 	else
206 		priv->tx_handler = sb_default_handler;
207 }
208 
209 /*
210  * Set priv ptr
211  *
212  * priv - priv void ptr to store in the device
213  */
214 void sandbox_eth_set_priv(int index, void *priv)
215 {
216 	struct udevice *dev;
217 	struct eth_sandbox_priv *dev_priv;
218 	int ret;
219 
220 	ret = uclass_get_device(UCLASS_ETH, index, &dev);
221 	if (ret)
222 		return;
223 
224 	dev_priv = dev_get_priv(dev);
225 
226 	dev_priv->priv = priv;
227 }
228 
229 static int sb_eth_start(struct udevice *dev)
230 {
231 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
232 
233 	debug("eth_sandbox: Start\n");
234 
235 	priv->recv_packets = 0;
236 	for (int i = 0; i < PKTBUFSRX; i++) {
237 		priv->recv_packet_buffer[i] = net_rx_packets[i];
238 		priv->recv_packet_length[i] = 0;
239 	}
240 
241 	return 0;
242 }
243 
244 static int sb_eth_send(struct udevice *dev, void *packet, int length)
245 {
246 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
247 
248 	debug("eth_sandbox: Send packet %d\n", length);
249 
250 	if (priv->disabled)
251 		return 0;
252 
253 	return priv->tx_handler(dev, packet, length);
254 }
255 
256 static int sb_eth_recv(struct udevice *dev, int flags, uchar **packetp)
257 {
258 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
259 
260 	if (skip_timeout) {
261 		sandbox_timer_add_offset(11000UL);
262 		skip_timeout = false;
263 	}
264 
265 	if (priv->recv_packets) {
266 		int lcl_recv_packet_length = priv->recv_packet_length[0];
267 
268 		debug("eth_sandbox: received packet[%d], %d waiting\n",
269 		      lcl_recv_packet_length, priv->recv_packets - 1);
270 		*packetp = priv->recv_packet_buffer[0];
271 		return lcl_recv_packet_length;
272 	}
273 	return 0;
274 }
275 
276 static int sb_eth_free_pkt(struct udevice *dev, uchar *packet, int length)
277 {
278 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
279 	int i;
280 
281 	if (!priv->recv_packets)
282 		return 0;
283 
284 	--priv->recv_packets;
285 	for (i = 0; i < priv->recv_packets; i++) {
286 		priv->recv_packet_length[i] = priv->recv_packet_length[i + 1];
287 		memcpy(priv->recv_packet_buffer[i],
288 		       priv->recv_packet_buffer[i + 1],
289 		       priv->recv_packet_length[i + 1]);
290 	}
291 	priv->recv_packet_length[priv->recv_packets] = 0;
292 
293 	return 0;
294 }
295 
296 static void sb_eth_stop(struct udevice *dev)
297 {
298 	debug("eth_sandbox: Stop\n");
299 }
300 
301 static int sb_eth_write_hwaddr(struct udevice *dev)
302 {
303 	struct eth_pdata *pdata = dev_get_platdata(dev);
304 
305 	debug("eth_sandbox %s: Write HW ADDR - %pM\n", dev->name,
306 	      pdata->enetaddr);
307 	return 0;
308 }
309 
310 static const struct eth_ops sb_eth_ops = {
311 	.start			= sb_eth_start,
312 	.send			= sb_eth_send,
313 	.recv			= sb_eth_recv,
314 	.free_pkt		= sb_eth_free_pkt,
315 	.stop			= sb_eth_stop,
316 	.write_hwaddr		= sb_eth_write_hwaddr,
317 };
318 
319 static int sb_eth_remove(struct udevice *dev)
320 {
321 	return 0;
322 }
323 
324 static int sb_eth_ofdata_to_platdata(struct udevice *dev)
325 {
326 	struct eth_pdata *pdata = dev_get_platdata(dev);
327 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
328 	const u8 *mac;
329 
330 	pdata->iobase = dev_read_addr(dev);
331 
332 	mac = dev_read_u8_array_ptr(dev, "fake-host-hwaddr", ARP_HLEN);
333 	if (!mac) {
334 		printf("'fake-host-hwaddr' is missing from the DT\n");
335 		return -EINVAL;
336 	}
337 	memcpy(priv->fake_host_hwaddr, mac, ARP_HLEN);
338 	priv->disabled = false;
339 	priv->tx_handler = sb_default_handler;
340 
341 	return 0;
342 }
343 
344 static const struct udevice_id sb_eth_ids[] = {
345 	{ .compatible = "sandbox,eth" },
346 	{ }
347 };
348 
349 U_BOOT_DRIVER(eth_sandbox) = {
350 	.name	= "eth_sandbox",
351 	.id	= UCLASS_ETH,
352 	.of_match = sb_eth_ids,
353 	.ofdata_to_platdata = sb_eth_ofdata_to_platdata,
354 	.remove	= sb_eth_remove,
355 	.ops	= &sb_eth_ops,
356 	.priv_auto_alloc_size = sizeof(struct eth_sandbox_priv),
357 	.platdata_auto_alloc_size = sizeof(struct eth_pdata),
358 };
359