drivers/net/sandbox.c

   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  * disabled: Will not respond
  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         bool disabled;
  30         uchar *recv_packet_buffer;
  31         int recv_packet_length;
  32 };
  33
  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         struct udevice *dev;
  45         struct eth_sandbox_priv *priv;
  46         int ret;
  47
  48         ret = uclass_get_device(UCLASS_ETH, index, &dev);
  49         if (ret)
  50                 return;
  51
  52         priv = dev_get_priv(dev);
  53         priv->disabled = disable;
  54 }
  55
  56 /*
  57  * sandbox_eth_skip_timeout()
  58  *
  59  * When the first packet read is attempted, fast-forward time
  60  */
  61 void sandbox_eth_skip_timeout(void)
  62 {
  63         skip_timeout = true;
  64 }
  65
  66 static int sb_eth_start(struct udevice *dev)
  67 {
  68         struct eth_sandbox_priv *priv = dev_get_priv(dev);
  69
  70         debug("eth_sandbox: Start\n");
  71
  72         priv->recv_packet_buffer = net_rx_packets[0];
  73
  74         return 0;
  75 }
  76
  77 static int sb_eth_send(struct udevice *dev, void *packet, int length)
  78 {
  79         struct eth_sandbox_priv *priv = dev_get_priv(dev);
  80         struct ethernet_hdr *eth = packet;
  81
  82         debug("eth_sandbox: Send packet %d\n", length);
  83
  84         if (priv->disabled)
  85                 return 0;
  86
  87         if (ntohs(eth->et_protlen) == PROT_ARP) {
  88                 struct arp_hdr *arp = packet + ETHER_HDR_SIZE;
  89
  90                 if (ntohs(arp->ar_op) == ARPOP_REQUEST) {
  91                         struct ethernet_hdr *eth_recv;
  92                         struct arp_hdr *arp_recv;
  93
  94                         /* store this as the assumed IP of the fake host */
  95                         priv->fake_host_ipaddr = net_read_ip(&arp->ar_tpa);
  96                         /* Formulate a fake response */
  97                         eth_recv = (void *)priv->recv_packet_buffer;
  98                         memcpy(eth_recv->et_dest, eth->et_src, ARP_HLEN);
  99                         memcpy(eth_recv->et_src, priv->fake_host_hwaddr,
 100                                ARP_HLEN);
 101                         eth_recv->et_protlen = htons(PROT_ARP);
 102
 103                         arp_recv = (void *)priv->recv_packet_buffer +
 104                                 ETHER_HDR_SIZE;
 105                         arp_recv->ar_hrd = htons(ARP_ETHER);
 106                         arp_recv->ar_pro = htons(PROT_IP);
 107                         arp_recv->ar_hln = ARP_HLEN;
 108                         arp_recv->ar_pln = ARP_PLEN;
 109                         arp_recv->ar_op = htons(ARPOP_REPLY);
 110                         memcpy(&arp_recv->ar_sha, priv->fake_host_hwaddr,
 111                                ARP_HLEN);
 112                         net_write_ip(&arp_recv->ar_spa, priv->fake_host_ipaddr);
 113                         memcpy(&arp_recv->ar_tha, &arp->ar_sha, ARP_HLEN);
 114                         net_copy_ip(&arp_recv->ar_tpa, &arp->ar_spa);
 115
 116                         priv->recv_packet_length = ETHER_HDR_SIZE +
 117                                 ARP_HDR_SIZE;
 118                 }
 119         } else if (ntohs(eth->et_protlen) == PROT_IP) {
 120                 struct ip_udp_hdr *ip = packet + ETHER_HDR_SIZE;
 121
 122                 if (ip->ip_p == IPPROTO_ICMP) {
 123                         struct icmp_hdr *icmp = (struct icmp_hdr *)&ip->udp_src;
 124
 125                         if (icmp->type == ICMP_ECHO_REQUEST) {
 126                                 struct ethernet_hdr *eth_recv;
 127                                 struct ip_udp_hdr *ipr;
 128                                 struct icmp_hdr *icmpr;
 129
 130                                 /* reply to the ping */
 131                                 memcpy(priv->recv_packet_buffer, packet,
 132                                        length);
 133                                 eth_recv = (void *)priv->recv_packet_buffer;
 134                                 ipr = (void *)priv->recv_packet_buffer +
 135                                         ETHER_HDR_SIZE;
 136                                 icmpr = (struct icmp_hdr *)&ipr->udp_src;
 137                                 memcpy(eth_recv->et_dest, eth->et_src,
 138                                        ARP_HLEN);
 139                                 memcpy(eth_recv->et_src, priv->fake_host_hwaddr,
 140                                        ARP_HLEN);
 141                                 ipr->ip_sum = 0;
 142                                 ipr->ip_off = 0;
 143                                 net_copy_ip((void *)&ipr->ip_dst, &ip->ip_src);
 144                                 net_write_ip((void *)&ipr->ip_src,
 145                                              priv->fake_host_ipaddr);
 146                                 ipr->ip_sum = compute_ip_checksum(ipr,
 147                                         IP_HDR_SIZE);
 148
 149                                 icmpr->type = ICMP_ECHO_REPLY;
 150                                 icmpr->checksum = 0;
 151                                 icmpr->checksum = compute_ip_checksum(icmpr,
 152                                         ICMP_HDR_SIZE);
 153
 154                                 priv->recv_packet_length = length;
 155                         }
 156                 }
 157         }
 158
 159         return 0;
 160 }
 161
 162 static int sb_eth_recv(struct udevice *dev, int flags, uchar **packetp)
 163 {
 164         struct eth_sandbox_priv *priv = dev_get_priv(dev);
 165
 166         if (skip_timeout) {
 167                 sandbox_timer_add_offset(11000UL);
 168                 skip_timeout = false;
 169         }
 170
 171         if (priv->recv_packet_length) {
 172                 int lcl_recv_packet_length = priv->recv_packet_length;
 173
 174                 debug("eth_sandbox: received packet %d\n",
 175                       priv->recv_packet_length);
 176                 priv->recv_packet_length = 0;
 177                 *packetp = priv->recv_packet_buffer;
 178                 return lcl_recv_packet_length;
 179         }
 180         return 0;
 181 }
 182
 183 static void sb_eth_stop(struct udevice *dev)
 184 {
 185         debug("eth_sandbox: Stop\n");
 186 }
 187
 188 static int sb_eth_write_hwaddr(struct udevice *dev)
 189 {
 190         struct eth_pdata *pdata = dev_get_platdata(dev);
 191
 192         debug("eth_sandbox %s: Write HW ADDR - %pM\n", dev->name,
 193               pdata->enetaddr);
 194         return 0;
 195 }
 196
 197 static const struct eth_ops sb_eth_ops = {
 198         .start                  = sb_eth_start,
 199         .send                   = sb_eth_send,
 200         .recv                   = sb_eth_recv,
 201         .stop                   = sb_eth_stop,
 202         .write_hwaddr           = sb_eth_write_hwaddr,
 203 };
 204
 205 static int sb_eth_remove(struct udevice *dev)
 206 {
 207         return 0;
 208 }
 209
 210 static int sb_eth_ofdata_to_platdata(struct udevice *dev)
 211 {
 212         struct eth_pdata *pdata = dev_get_platdata(dev);
 213         struct eth_sandbox_priv *priv = dev_get_priv(dev);
 214         const u8 *mac;
 215
 216         pdata->iobase = dev_read_addr(dev);
 217
 218         mac = dev_read_u8_array_ptr(dev, "fake-host-hwaddr", ARP_HLEN);
 219         if (!mac) {
 220                 printf("'fake-host-hwaddr' is missing from the DT\n");
 221                 return -EINVAL;
 222         }
 223         memcpy(priv->fake_host_hwaddr, mac, ARP_HLEN);
 224         priv->disabled = false;
 225
 226         return 0;
 227 }
 228
 229 static const struct udevice_id sb_eth_ids[] = {
 230         { .compatible = "sandbox,eth" },
 231         { }
 232 };
 233
 234 U_BOOT_DRIVER(eth_sandbox) = {
 235         .name   = "eth_sandbox",
 236         .id     = UCLASS_ETH,
 237         .of_match = sb_eth_ids,
 238         .ofdata_to_platdata = sb_eth_ofdata_to_platdata,
 239         .remove = sb_eth_remove,
 240         .ops    = &sb_eth_ops,
 241         .priv_auto_alloc_size = sizeof(struct eth_sandbox_priv),
 242         .platdata_auto_alloc_size = sizeof(struct eth_pdata),
 243 };