drivers/net/sandbox.c

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