qemu/roms/SLOF/clients/net-snk/app/netlib/bootp.c

   1 /******************************************************************************
   2  * Copyright (c) 2004, 2008 IBM Corporation
   3  * All rights reserved.
   4  * This program and the accompanying materials
   5  * are made available under the terms of the BSD License
   6  * which accompanies this distribution, and is available at
   7  * http://www.opensource.org/licenses/bsd-license.php
   8  *
   9  * Contributors:
  10  *     IBM Corporation - initial implementation
  11  *****************************************************************************/
  12
  13
  14 #include <stdio.h>
  15 #include <string.h>
  16 #include <sys/socket.h>
  17 #include <time.h>
  18
  19 #include <ethernet.h>
  20 #include <ipv4.h>
  21 #include <udp.h>
  22 #include <dhcp.h>
  23
  24 #define DEBUG 0
  25
  26 static char * response_buffer;
  27
  28 #if DEBUG
  29 static void
  30 print_ip(char *ip)
  31 {
  32         printf("%d.%d.%d.%d\n", ip[0], ip[1], ip[2], ip[3]);
  33 }
  34 #endif
  35
  36 /* IP header checksum calculation */
  37 static unsigned short
  38 checksum(unsigned short *packet, int words)
  39 {
  40         unsigned long checksum;
  41         for (checksum = 0; words > 0; words--)
  42                 checksum += *packet++;
  43         checksum = (checksum >> 16) + (checksum & 0xffff);
  44         checksum += (checksum >> 16);
  45         return ~checksum;
  46 }
  47
  48
  49 static int
  50 send_bootp(filename_ip_t * fn_ip)
  51 {
  52 #if DEBUG
  53         int i;
  54 #endif
  55         unsigned int packetsize =
  56             sizeof(struct iphdr) + sizeof(struct ethhdr) +
  57             sizeof(struct udphdr) + sizeof(struct btphdr);
  58         unsigned char packet[packetsize];
  59         struct iphdr *iph;
  60         struct udphdr *udph;
  61         struct btphdr *btph;
  62
  63         iph = (struct iphdr *) packet;
  64         udph = (struct udphdr *) (iph + 1);
  65         btph = (struct btphdr *) (udph + 1);
  66
  67         memset(packet, 0, packetsize);
  68
  69         fill_iphdr((uint8_t *) iph, htons(packetsize - sizeof(struct ethhdr)),
  70                    IPTYPE_UDP, 0, fn_ip->server_ip);
  71         fill_udphdr((uint8_t *) udph,
  72                     htons(sizeof(struct udphdr) + sizeof(struct btphdr)),
  73                     htons(UDPPORT_BOOTPC), htons(UDPPORT_BOOTPS));
  74         btph->op = 1;
  75         btph->htype = 1;
  76         btph->hlen = 6;
  77         strcpy((char *) btph->file, "bla");
  78         memcpy(btph->chaddr, get_mac_address(), 6);
  79
  80 #if DEBUG
  81         printf("Sending packet\n");
  82         printf("Packet is ");
  83         for (i = 0; i < packetsize; i++)
  84                 printf(" %02x", packet[i]);
  85         printf(".\n");
  86 #endif
  87
  88         send_ipv4(fn_ip->fd, packet, iph->ip_len);
  89 #if DEBUG
  90         printf("%d bytes transmitted over socket.\n", i);
  91 #endif
  92
  93         return 0;
  94 }
  95
  96
  97 static int
  98 receive_bootp(filename_ip_t * fn_ip)
  99 {
 100         int len, old_sum;
 101         unsigned int packetsize = 2000;
 102         unsigned char packet[packetsize];
 103         struct iphdr *iph;
 104         struct udphdr *udph;
 105         struct btphdr *btph;
 106
 107 #if DEBUG
 108         struct ethhdr *ethh;
 109         ethh = (struct ethhdr *) packet;
 110 #endif
 111
 112         iph = (struct iphdr *) (packet + sizeof(struct ethhdr));
 113         udph = (struct udphdr *) (iph + 1);
 114         btph = (struct btphdr *) (udph + 1);
 115
 116         memset(packet, 0, packetsize);
 117
 118         /* setting up a timer with a timeout of one second */
 119         set_timer(TICKS_SEC);
 120
 121         do {
 122
 123                 /* let's receive a packet */
 124                 len = recv(fn_ip->fd, packet, packetsize, 0);
 125
 126 #if DEBUG
 127                 int j;
 128                 printf("%d bytes received, %d expected \n", len, packetsize);
 129                 if (len == 346) {
 130                         printf("Rec packet\n");
 131                         printf("Packet is ");
 132                         for (j = 0; j < len; j++) {
 133                                 if (j % 16 == 0)
 134                                         printf("\n");
 135                                 printf(" %02x", packet[j]);
 136                         }
 137                         printf(".\n");
 138                 }
 139 #endif
 140                 if (len == 0)
 141                         continue;
 142
 143                 /* check if the ip checksum is correct */
 144                 old_sum = iph->ip_sum;
 145                 iph->ip_sum = 0x00;
 146                 if (old_sum !=
 147                     checksum((unsigned short *) iph, sizeof(struct iphdr) >> 1))
 148                         /* checksum failed */
 149                         continue;
 150                 /* is it a udp packet */
 151                 if (iph->ip_p != IPTYPE_UDP)
 152                         continue;
 153                 /* check if the source port and destination port and the packet
 154                  * say that it is a bootp answer */
 155                 if (udph->uh_dport != htons(UDPPORT_BOOTPC) || udph->uh_sport != htons(UDPPORT_BOOTPS))
 156                         continue;
 157                 /* check if it is a Boot Reply */
 158                 if (btph->op != 2)
 159                         continue;
 160                 /* Comparing our mac address with the one in the bootp reply */
 161                 if (memcmp(get_mac_address(), btph->chaddr, ETH_ALEN))
 162                         continue;
 163
 164                 if(response_buffer)
 165                         memcpy(response_buffer, btph, 1720);
 166
 167                 fn_ip->own_ip = btph->yiaddr;
 168                 fn_ip->server_ip = btph->siaddr;
 169                 strcpy((char *) fn_ip->filename, (char *) btph->file);
 170
 171 #if DEBUG
 172                 printf("\nThese are the details of the bootp reply:\n");
 173                 printf("Our IP address: ");
 174                 print_ip((char*) &fn_ip->own_ip);
 175                 printf("Next server IP address: ");
 176                 print_ip((char*) &fn_ip->server_ip);
 177                 printf("Boot file name: %s\n", btph->file);
 178                 printf("Packet is: %s\n", btph->file);
 179                 for (j = 0; j < len; j++) {
 180                         if (j % 16 == 0)
 181                                 printf("\n");
 182                         printf(" %02x", packet[j]);
 183                 }
 184                 printf(".\n");
 185                 printf("fn_ip->own_mac: %02x:%02x:%02x:%02x:%02x:%02x\n",
 186                         get_mac_address()[0], get_mac_address()[1],
 187                         get_mac_address()[2], get_mac_address()[3],
 188                         get_mac_address()[4], get_mac_address()[5]);
 189                 printf("Header ethh->dest_mac: %02x:%02x:%02x:%02x:%02x:%02x\n",
 190                        ethh->dest_mac[0], ethh->dest_mac[1], ethh->dest_mac[2],
 191                        ethh->dest_mac[3], ethh->dest_mac[4], ethh->dest_mac[5]);
 192                 printf("Header ethh->src_mac: %02x:%02x:%02x:%02x:%02x:%02x\n",
 193                        ethh->src_mac[0], ethh->src_mac[1], ethh->src_mac[2],
 194                        ethh->src_mac[3], ethh->src_mac[4], ethh->src_mac[5]);
 195                 printf("Header ethh->typ: %x\n",ethh->type);
 196                 printf("Header iph->ip_hlv: %x\n",iph->ip_hlv);
 197                 printf("Header iph->ip_len: %x\n",iph->ip_len);
 198                 printf("Header iph->ip_id: %x\n",iph->ip_id);
 199                 printf("Header iph->ip_off: %x\n",iph->ip_off);
 200                 printf("Header iph->ip_ttl: %x\n",iph->ip_ttl);
 201                 printf("Header iph->ip_p: %x\n",iph->ip_p);
 202                 printf("Header iph->ip_sum: %x\n",iph->ip_sum);
 203                 printf("Header iph->ip_src: %x\n",iph->ip_src);
 204                 printf("Header iph->ip_dst: %x\n",iph->ip_dst);
 205
 206                 printf("Header btph->op: %x\n",btph->op);
 207                 printf("Header btph->htype: %x\n",btph->htype);
 208                 printf("Header btph->hlen: %x\n",btph->hlen);
 209                 printf("Header btph->hops: %x\n",btph->hops);
 210                 printf("Header btph->xid: %x\n",btph->xid);
 211                 printf("Header btph->secs: %x\n",btph->secs);
 212                 printf("Header btph->ciaddr: %x\n",btph->ciaddr);
 213                 printf("Header btph->yiaddr: %x\n",btph->yiaddr);
 214                 printf("Header btph->siaddr: %x\n",btph->siaddr);
 215                 printf("Header btph->giaddr: %x\n",btph->giaddr);
 216
 217                 printf("Header btph->chaddr: %02x:%02x:%02x:%02x:%02x:%02x:\n",
 218                        btph->chaddr[0], btph->chaddr[1], btph->chaddr[2],
 219                        btph->chaddr[3], btph->chaddr[4], btph->chaddr[5]);
 220 #endif
 221                 return 0;
 222
 223                 /* only do this for the time specified during set_timer() */
 224         } while (get_timer() > 0);
 225         return -1;
 226 }
 227
 228
 229 int
 230 bootp(char *ret_buffer, filename_ip_t * fn_ip, unsigned int retries)
 231 {
 232         int i = (int) retries+1;
 233         fn_ip->own_ip = 0;
 234
 235         printf("   ");
 236
 237         response_buffer = ret_buffer;
 238
 239         do {
 240                 printf("\b\b%02d", i);
 241                 if (!i--) {
 242                         printf("\nGiving up after %d bootp requests\n",
 243                                retries+1);
 244                         return -1;
 245                 }
 246                 send_bootp(fn_ip);
 247                 /* if the timer in receive_bootp expired it will return
 248                  * -1 and we will just send another bootp request just
 249                  * in case the previous one was lost. And because we don't
 250                  * trust the network cable we keep on doing this 30 times */
 251         } while (receive_bootp(fn_ip) != 0);
 252         printf("\b\b\b");
 253         return 0;
 254 }