xref: /openbmc/u-boot/drivers/net/sandbox.c (revision 90c08fa0)
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/test.h>
14 
15 DECLARE_GLOBAL_DATA_PTR;
16 
17 /**
18  * struct eth_sandbox_priv - memory for sandbox mock driver
19  *
20  * fake_host_hwaddr: MAC address of mocked machine
21  * fake_host_ipaddr: IP address of mocked machine
22  * recv_packet_buffer: buffer of the packet returned as received
23  * recv_packet_length: length of the packet returned as received
24  */
25 struct eth_sandbox_priv {
26 	uchar fake_host_hwaddr[ARP_HLEN];
27 	struct in_addr fake_host_ipaddr;
28 	uchar *recv_packet_buffer;
29 	int recv_packet_length;
30 };
31 
32 static bool disabled[8] = {false};
33 static bool skip_timeout;
34 
35 /*
36  * sandbox_eth_disable_response()
37  *
38  * index - The alias index (also DM seq number)
39  * disable - If non-zero, ignore sent packets and don't send mock response
40  */
41 void sandbox_eth_disable_response(int index, bool disable)
42 {
43 	disabled[index] = disable;
44 }
45 
46 /*
47  * sandbox_eth_skip_timeout()
48  *
49  * When the first packet read is attempted, fast-forward time
50  */
51 void sandbox_eth_skip_timeout(void)
52 {
53 	skip_timeout = true;
54 }
55 
56 static int sb_eth_start(struct udevice *dev)
57 {
58 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
59 
60 	debug("eth_sandbox: Start\n");
61 
62 	fdtdec_get_byte_array(gd->fdt_blob, dev_of_offset(dev),
63 			      "fake-host-hwaddr", priv->fake_host_hwaddr,
64 			      ARP_HLEN);
65 	priv->recv_packet_buffer = net_rx_packets[0];
66 	return 0;
67 }
68 
69 static int sb_eth_send(struct udevice *dev, void *packet, int length)
70 {
71 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
72 	struct ethernet_hdr *eth = packet;
73 
74 	debug("eth_sandbox: Send packet %d\n", length);
75 
76 	if (dev->seq >= 0 && dev->seq < ARRAY_SIZE(disabled) &&
77 	    disabled[dev->seq])
78 		return 0;
79 
80 	if (ntohs(eth->et_protlen) == PROT_ARP) {
81 		struct arp_hdr *arp = packet + ETHER_HDR_SIZE;
82 
83 		if (ntohs(arp->ar_op) == ARPOP_REQUEST) {
84 			struct ethernet_hdr *eth_recv;
85 			struct arp_hdr *arp_recv;
86 
87 			/* store this as the assumed IP of the fake host */
88 			priv->fake_host_ipaddr = net_read_ip(&arp->ar_tpa);
89 			/* Formulate a fake response */
90 			eth_recv = (void *)priv->recv_packet_buffer;
91 			memcpy(eth_recv->et_dest, eth->et_src, ARP_HLEN);
92 			memcpy(eth_recv->et_src, priv->fake_host_hwaddr,
93 			       ARP_HLEN);
94 			eth_recv->et_protlen = htons(PROT_ARP);
95 
96 			arp_recv = (void *)priv->recv_packet_buffer +
97 				ETHER_HDR_SIZE;
98 			arp_recv->ar_hrd = htons(ARP_ETHER);
99 			arp_recv->ar_pro = htons(PROT_IP);
100 			arp_recv->ar_hln = ARP_HLEN;
101 			arp_recv->ar_pln = ARP_PLEN;
102 			arp_recv->ar_op = htons(ARPOP_REPLY);
103 			memcpy(&arp_recv->ar_sha, priv->fake_host_hwaddr,
104 			       ARP_HLEN);
105 			net_write_ip(&arp_recv->ar_spa, priv->fake_host_ipaddr);
106 			memcpy(&arp_recv->ar_tha, &arp->ar_sha, ARP_HLEN);
107 			net_copy_ip(&arp_recv->ar_tpa, &arp->ar_spa);
108 
109 			priv->recv_packet_length = ETHER_HDR_SIZE +
110 				ARP_HDR_SIZE;
111 		}
112 	} else if (ntohs(eth->et_protlen) == PROT_IP) {
113 		struct ip_udp_hdr *ip = packet + ETHER_HDR_SIZE;
114 
115 		if (ip->ip_p == IPPROTO_ICMP) {
116 			struct icmp_hdr *icmp = (struct icmp_hdr *)&ip->udp_src;
117 
118 			if (icmp->type == ICMP_ECHO_REQUEST) {
119 				struct ethernet_hdr *eth_recv;
120 				struct ip_udp_hdr *ipr;
121 				struct icmp_hdr *icmpr;
122 
123 				/* reply to the ping */
124 				memcpy(priv->recv_packet_buffer, packet,
125 				       length);
126 				eth_recv = (void *)priv->recv_packet_buffer;
127 				ipr = (void *)priv->recv_packet_buffer +
128 					ETHER_HDR_SIZE;
129 				icmpr = (struct icmp_hdr *)&ipr->udp_src;
130 				memcpy(eth_recv->et_dest, eth->et_src,
131 				       ARP_HLEN);
132 				memcpy(eth_recv->et_src, priv->fake_host_hwaddr,
133 				       ARP_HLEN);
134 				ipr->ip_sum = 0;
135 				ipr->ip_off = 0;
136 				net_copy_ip((void *)&ipr->ip_dst, &ip->ip_src);
137 				net_write_ip((void *)&ipr->ip_src,
138 					     priv->fake_host_ipaddr);
139 				ipr->ip_sum = compute_ip_checksum(ipr,
140 					IP_HDR_SIZE);
141 
142 				icmpr->type = ICMP_ECHO_REPLY;
143 				icmpr->checksum = 0;
144 				icmpr->checksum = compute_ip_checksum(icmpr,
145 					ICMP_HDR_SIZE);
146 
147 				priv->recv_packet_length = length;
148 			}
149 		}
150 	}
151 
152 	return 0;
153 }
154 
155 static int sb_eth_recv(struct udevice *dev, int flags, uchar **packetp)
156 {
157 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
158 
159 	if (skip_timeout) {
160 		sandbox_timer_add_offset(11000UL);
161 		skip_timeout = false;
162 	}
163 
164 	if (priv->recv_packet_length) {
165 		int lcl_recv_packet_length = priv->recv_packet_length;
166 
167 		debug("eth_sandbox: received packet %d\n",
168 		      priv->recv_packet_length);
169 		priv->recv_packet_length = 0;
170 		*packetp = priv->recv_packet_buffer;
171 		return lcl_recv_packet_length;
172 	}
173 	return 0;
174 }
175 
176 static void sb_eth_stop(struct udevice *dev)
177 {
178 	debug("eth_sandbox: Stop\n");
179 }
180 
181 static int sb_eth_write_hwaddr(struct udevice *dev)
182 {
183 	struct eth_pdata *pdata = dev_get_platdata(dev);
184 
185 	debug("eth_sandbox %s: Write HW ADDR - %pM\n", dev->name,
186 	      pdata->enetaddr);
187 	return 0;
188 }
189 
190 static const struct eth_ops sb_eth_ops = {
191 	.start			= sb_eth_start,
192 	.send			= sb_eth_send,
193 	.recv			= sb_eth_recv,
194 	.stop			= sb_eth_stop,
195 	.write_hwaddr		= sb_eth_write_hwaddr,
196 };
197 
198 static int sb_eth_remove(struct udevice *dev)
199 {
200 	return 0;
201 }
202 
203 static int sb_eth_ofdata_to_platdata(struct udevice *dev)
204 {
205 	struct eth_pdata *pdata = dev_get_platdata(dev);
206 
207 	pdata->iobase = devfdt_get_addr(dev);
208 	return 0;
209 }
210 
211 static const struct udevice_id sb_eth_ids[] = {
212 	{ .compatible = "sandbox,eth" },
213 	{ }
214 };
215 
216 U_BOOT_DRIVER(eth_sandbox) = {
217 	.name	= "eth_sandbox",
218 	.id	= UCLASS_ETH,
219 	.of_match = sb_eth_ids,
220 	.ofdata_to_platdata = sb_eth_ofdata_to_platdata,
221 	.remove	= sb_eth_remove,
222 	.ops	= &sb_eth_ops,
223 	.priv_auto_alloc_size = sizeof(struct eth_sandbox_priv),
224 	.platdata_auto_alloc_size = sizeof(struct eth_pdata),
225 };
226