xref: /openbmc/u-boot/drivers/net/sandbox.c (revision 33b78476)
1 /*
2  * Copyright (c) 2015 National Instruments
3  *
4  * (C) Copyright 2015
5  * Joe Hershberger <joe.hershberger@ni.com>
6  *
7  * SPDX-License-Identifier:	GPL-2.0
8  */
9 
10 #include <common.h>
11 #include <dm.h>
12 #include <malloc.h>
13 #include <net.h>
14 #include <asm/test.h>
15 
16 DECLARE_GLOBAL_DATA_PTR;
17 
18 /**
19  * struct eth_sandbox_priv - memory for sandbox mock driver
20  *
21  * fake_host_hwaddr: MAC address of mocked machine
22  * fake_host_ipaddr: IP address of mocked machine
23  * recv_packet_buffer: buffer of the packet returned as received
24  * recv_packet_length: length of the packet returned as received
25  */
26 struct eth_sandbox_priv {
27 	uchar fake_host_hwaddr[ARP_HLEN];
28 	struct in_addr fake_host_ipaddr;
29 	uchar *recv_packet_buffer;
30 	int recv_packet_length;
31 };
32 
33 static bool disabled[8] = {false};
34 static bool skip_timeout;
35 
36 /*
37  * sandbox_eth_disable_response()
38  *
39  * index - The alias index (also DM seq number)
40  * disable - If non-zero, ignore sent packets and don't send mock response
41  */
42 void sandbox_eth_disable_response(int index, bool disable)
43 {
44 	disabled[index] = disable;
45 }
46 
47 /*
48  * sandbox_eth_skip_timeout()
49  *
50  * When the first packet read is attempted, fast-forward time
51  */
52 void sandbox_eth_skip_timeout(void)
53 {
54 	skip_timeout = true;
55 }
56 
57 static int sb_eth_start(struct udevice *dev)
58 {
59 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
60 
61 	debug("eth_sandbox: Start\n");
62 
63 	fdtdec_get_byte_array(gd->fdt_blob, dev_of_offset(dev),
64 			      "fake-host-hwaddr", priv->fake_host_hwaddr,
65 			      ARP_HLEN);
66 	priv->recv_packet_buffer = net_rx_packets[0];
67 	return 0;
68 }
69 
70 static int sb_eth_send(struct udevice *dev, void *packet, int length)
71 {
72 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
73 	struct ethernet_hdr *eth = packet;
74 
75 	debug("eth_sandbox: Send packet %d\n", length);
76 
77 	if (dev->seq >= 0 && dev->seq < ARRAY_SIZE(disabled) &&
78 	    disabled[dev->seq])
79 		return 0;
80 
81 	if (ntohs(eth->et_protlen) == PROT_ARP) {
82 		struct arp_hdr *arp = packet + ETHER_HDR_SIZE;
83 
84 		if (ntohs(arp->ar_op) == ARPOP_REQUEST) {
85 			struct ethernet_hdr *eth_recv;
86 			struct arp_hdr *arp_recv;
87 
88 			/* store this as the assumed IP of the fake host */
89 			priv->fake_host_ipaddr = net_read_ip(&arp->ar_tpa);
90 			/* Formulate a fake response */
91 			eth_recv = (void *)priv->recv_packet_buffer;
92 			memcpy(eth_recv->et_dest, eth->et_src, ARP_HLEN);
93 			memcpy(eth_recv->et_src, priv->fake_host_hwaddr,
94 			       ARP_HLEN);
95 			eth_recv->et_protlen = htons(PROT_ARP);
96 
97 			arp_recv = (void *)priv->recv_packet_buffer +
98 				ETHER_HDR_SIZE;
99 			arp_recv->ar_hrd = htons(ARP_ETHER);
100 			arp_recv->ar_pro = htons(PROT_IP);
101 			arp_recv->ar_hln = ARP_HLEN;
102 			arp_recv->ar_pln = ARP_PLEN;
103 			arp_recv->ar_op = htons(ARPOP_REPLY);
104 			memcpy(&arp_recv->ar_sha, priv->fake_host_hwaddr,
105 			       ARP_HLEN);
106 			net_write_ip(&arp_recv->ar_spa, priv->fake_host_ipaddr);
107 			memcpy(&arp_recv->ar_tha, &arp->ar_sha, ARP_HLEN);
108 			net_copy_ip(&arp_recv->ar_tpa, &arp->ar_spa);
109 
110 			priv->recv_packet_length = ETHER_HDR_SIZE +
111 				ARP_HDR_SIZE;
112 		}
113 	} else if (ntohs(eth->et_protlen) == PROT_IP) {
114 		struct ip_udp_hdr *ip = packet + ETHER_HDR_SIZE;
115 
116 		if (ip->ip_p == IPPROTO_ICMP) {
117 			struct icmp_hdr *icmp = (struct icmp_hdr *)&ip->udp_src;
118 
119 			if (icmp->type == ICMP_ECHO_REQUEST) {
120 				struct ethernet_hdr *eth_recv;
121 				struct ip_udp_hdr *ipr;
122 				struct icmp_hdr *icmpr;
123 
124 				/* reply to the ping */
125 				memcpy(priv->recv_packet_buffer, packet,
126 				       length);
127 				eth_recv = (void *)priv->recv_packet_buffer;
128 				ipr = (void *)priv->recv_packet_buffer +
129 					ETHER_HDR_SIZE;
130 				icmpr = (struct icmp_hdr *)&ipr->udp_src;
131 				memcpy(eth_recv->et_dest, eth->et_src,
132 				       ARP_HLEN);
133 				memcpy(eth_recv->et_src, priv->fake_host_hwaddr,
134 				       ARP_HLEN);
135 				ipr->ip_sum = 0;
136 				ipr->ip_off = 0;
137 				net_copy_ip((void *)&ipr->ip_dst, &ip->ip_src);
138 				net_write_ip((void *)&ipr->ip_src,
139 					     priv->fake_host_ipaddr);
140 				ipr->ip_sum = compute_ip_checksum(ipr,
141 					IP_HDR_SIZE);
142 
143 				icmpr->type = ICMP_ECHO_REPLY;
144 				icmpr->checksum = 0;
145 				icmpr->checksum = compute_ip_checksum(icmpr,
146 					ICMP_HDR_SIZE);
147 
148 				priv->recv_packet_length = length;
149 			}
150 		}
151 	}
152 
153 	return 0;
154 }
155 
156 static int sb_eth_recv(struct udevice *dev, int flags, uchar **packetp)
157 {
158 	struct eth_sandbox_priv *priv = dev_get_priv(dev);
159 
160 	if (skip_timeout) {
161 		sandbox_timer_add_offset(11000UL);
162 		skip_timeout = false;
163 	}
164 
165 	if (priv->recv_packet_length) {
166 		int lcl_recv_packet_length = priv->recv_packet_length;
167 
168 		debug("eth_sandbox: received packet %d\n",
169 		      priv->recv_packet_length);
170 		priv->recv_packet_length = 0;
171 		*packetp = priv->recv_packet_buffer;
172 		return lcl_recv_packet_length;
173 	}
174 	return 0;
175 }
176 
177 static void sb_eth_stop(struct udevice *dev)
178 {
179 	debug("eth_sandbox: Stop\n");
180 }
181 
182 static int sb_eth_write_hwaddr(struct udevice *dev)
183 {
184 	struct eth_pdata *pdata = dev_get_platdata(dev);
185 
186 	debug("eth_sandbox %s: Write HW ADDR - %pM\n", dev->name,
187 	      pdata->enetaddr);
188 	return 0;
189 }
190 
191 static const struct eth_ops sb_eth_ops = {
192 	.start			= sb_eth_start,
193 	.send			= sb_eth_send,
194 	.recv			= sb_eth_recv,
195 	.stop			= sb_eth_stop,
196 	.write_hwaddr		= sb_eth_write_hwaddr,
197 };
198 
199 static int sb_eth_remove(struct udevice *dev)
200 {
201 	return 0;
202 }
203 
204 static int sb_eth_ofdata_to_platdata(struct udevice *dev)
205 {
206 	struct eth_pdata *pdata = dev_get_platdata(dev);
207 
208 	pdata->iobase = dev_get_addr(dev);
209 	return 0;
210 }
211 
212 static const struct udevice_id sb_eth_ids[] = {
213 	{ .compatible = "sandbox,eth" },
214 	{ }
215 };
216 
217 U_BOOT_DRIVER(eth_sandbox) = {
218 	.name	= "eth_sandbox",
219 	.id	= UCLASS_ETH,
220 	.of_match = sb_eth_ids,
221 	.ofdata_to_platdata = sb_eth_ofdata_to_platdata,
222 	.remove	= sb_eth_remove,
223 	.ops	= &sb_eth_ops,
224 	.priv_auto_alloc_size = sizeof(struct eth_sandbox_priv),
225 	.platdata_auto_alloc_size = sizeof(struct eth_pdata),
226 };
227