fddi.c 5.7 KB

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  1. /*
  2. * INET An implementation of the TCP/IP protocol suite for the LINUX
  3. * operating system. INET is implemented using the BSD Socket
  4. * interface as the means of communication with the user level.
  5. *
  6. * FDDI-type device handling.
  7. *
  8. * Version: @(#)fddi.c 1.0.0 08/12/96
  9. *
  10. * Authors: Lawrence V. Stefani, <stefani@lkg.dec.com>
  11. *
  12. * fddi.c is based on previous eth.c and tr.c work by
  13. * Ross Biro
  14. * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  15. * Mark Evans, <evansmp@uhura.aston.ac.uk>
  16. * Florian La Roche, <rzsfl@rz.uni-sb.de>
  17. * Alan Cox, <gw4pts@gw4pts.ampr.org>
  18. *
  19. * This program is free software; you can redistribute it and/or
  20. * modify it under the terms of the GNU General Public License
  21. * as published by the Free Software Foundation; either version
  22. * 2 of the License, or (at your option) any later version.
  23. *
  24. * Changes
  25. * Alan Cox : New arp/rebuild header
  26. * Maciej W. Rozycki : IPv6 support
  27. */
  28. #include <linux/module.h>
  29. #include <asm/system.h>
  30. #include <linux/types.h>
  31. #include <linux/kernel.h>
  32. #include <linux/string.h>
  33. #include <linux/mm.h>
  34. #include <linux/socket.h>
  35. #include <linux/in.h>
  36. #include <linux/inet.h>
  37. #include <linux/netdevice.h>
  38. #include <linux/fddidevice.h>
  39. #include <linux/if_ether.h>
  40. #include <linux/skbuff.h>
  41. #include <linux/errno.h>
  42. #include <net/arp.h>
  43. #include <net/sock.h>
  44. /*
  45. * Create the FDDI MAC header for an arbitrary protocol layer
  46. *
  47. * saddr=NULL means use device source address
  48. * daddr=NULL means leave destination address (eg unresolved arp)
  49. */
  50. static int fddi_header(struct sk_buff *skb, struct net_device *dev,
  51. unsigned short type,
  52. void *daddr, void *saddr, unsigned len)
  53. {
  54. int hl = FDDI_K_SNAP_HLEN;
  55. struct fddihdr *fddi;
  56. if(type != ETH_P_IP && type != ETH_P_IPV6 && type != ETH_P_ARP)
  57. hl=FDDI_K_8022_HLEN-3;
  58. fddi = (struct fddihdr *)skb_push(skb, hl);
  59. fddi->fc = FDDI_FC_K_ASYNC_LLC_DEF;
  60. if(type == ETH_P_IP || type == ETH_P_IPV6 || type == ETH_P_ARP)
  61. {
  62. fddi->hdr.llc_snap.dsap = FDDI_EXTENDED_SAP;
  63. fddi->hdr.llc_snap.ssap = FDDI_EXTENDED_SAP;
  64. fddi->hdr.llc_snap.ctrl = FDDI_UI_CMD;
  65. fddi->hdr.llc_snap.oui[0] = 0x00;
  66. fddi->hdr.llc_snap.oui[1] = 0x00;
  67. fddi->hdr.llc_snap.oui[2] = 0x00;
  68. fddi->hdr.llc_snap.ethertype = htons(type);
  69. }
  70. /* Set the source and destination hardware addresses */
  71. if (saddr != NULL)
  72. memcpy(fddi->saddr, saddr, dev->addr_len);
  73. else
  74. memcpy(fddi->saddr, dev->dev_addr, dev->addr_len);
  75. if (daddr != NULL)
  76. {
  77. memcpy(fddi->daddr, daddr, dev->addr_len);
  78. return(hl);
  79. }
  80. return(-hl);
  81. }
  82. /*
  83. * Rebuild the FDDI MAC header. This is called after an ARP
  84. * (or in future other address resolution) has completed on
  85. * this sk_buff. We now let ARP fill in the other fields.
  86. */
  87. static int fddi_rebuild_header(struct sk_buff *skb)
  88. {
  89. struct fddihdr *fddi = (struct fddihdr *)skb->data;
  90. #ifdef CONFIG_INET
  91. if (fddi->hdr.llc_snap.ethertype == __constant_htons(ETH_P_IP))
  92. /* Try to get ARP to resolve the header and fill destination address */
  93. return arp_find(fddi->daddr, skb);
  94. else
  95. #endif
  96. {
  97. printk("%s: Don't know how to resolve type %04X addresses.\n",
  98. skb->dev->name, ntohs(fddi->hdr.llc_snap.ethertype));
  99. return(0);
  100. }
  101. }
  102. /*
  103. * Determine the packet's protocol ID and fill in skb fields.
  104. * This routine is called before an incoming packet is passed
  105. * up. It's used to fill in specific skb fields and to set
  106. * the proper pointer to the start of packet data (skb->data).
  107. */
  108. __be16 fddi_type_trans(struct sk_buff *skb, struct net_device *dev)
  109. {
  110. struct fddihdr *fddi = (struct fddihdr *)skb->data;
  111. __be16 type;
  112. /*
  113. * Set mac.raw field to point to FC byte, set data field to point
  114. * to start of packet data. Assume 802.2 SNAP frames for now.
  115. */
  116. skb->mac.raw = skb->data; /* point to frame control (FC) */
  117. if(fddi->hdr.llc_8022_1.dsap==0xe0)
  118. {
  119. skb_pull(skb, FDDI_K_8022_HLEN-3);
  120. type = __constant_htons(ETH_P_802_2);
  121. }
  122. else
  123. {
  124. skb_pull(skb, FDDI_K_SNAP_HLEN); /* adjust for 21 byte header */
  125. type=fddi->hdr.llc_snap.ethertype;
  126. }
  127. /* Set packet type based on destination address and flag settings */
  128. if (*fddi->daddr & 0x01)
  129. {
  130. if (memcmp(fddi->daddr, dev->broadcast, FDDI_K_ALEN) == 0)
  131. skb->pkt_type = PACKET_BROADCAST;
  132. else
  133. skb->pkt_type = PACKET_MULTICAST;
  134. }
  135. else if (dev->flags & IFF_PROMISC)
  136. {
  137. if (memcmp(fddi->daddr, dev->dev_addr, FDDI_K_ALEN))
  138. skb->pkt_type = PACKET_OTHERHOST;
  139. }
  140. /* Assume 802.2 SNAP frames, for now */
  141. return(type);
  142. }
  143. EXPORT_SYMBOL(fddi_type_trans);
  144. static int fddi_change_mtu(struct net_device *dev, int new_mtu)
  145. {
  146. if ((new_mtu < FDDI_K_SNAP_HLEN) || (new_mtu > FDDI_K_SNAP_DLEN))
  147. return(-EINVAL);
  148. dev->mtu = new_mtu;
  149. return(0);
  150. }
  151. static void fddi_setup(struct net_device *dev)
  152. {
  153. dev->change_mtu = fddi_change_mtu;
  154. dev->hard_header = fddi_header;
  155. dev->rebuild_header = fddi_rebuild_header;
  156. dev->type = ARPHRD_FDDI;
  157. dev->hard_header_len = FDDI_K_SNAP_HLEN+3; /* Assume 802.2 SNAP hdr len + 3 pad bytes */
  158. dev->mtu = FDDI_K_SNAP_DLEN; /* Assume max payload of 802.2 SNAP frame */
  159. dev->addr_len = FDDI_K_ALEN;
  160. dev->tx_queue_len = 100; /* Long queues on FDDI */
  161. dev->flags = IFF_BROADCAST | IFF_MULTICAST;
  162. memset(dev->broadcast, 0xFF, FDDI_K_ALEN);
  163. }
  164. /**
  165. * alloc_fddidev - Register FDDI device
  166. * @sizeof_priv: Size of additional driver-private structure to be allocated
  167. * for this FDDI device
  168. *
  169. * Fill in the fields of the device structure with FDDI-generic values.
  170. *
  171. * Constructs a new net device, complete with a private data area of
  172. * size @sizeof_priv. A 32-byte (not bit) alignment is enforced for
  173. * this private data area.
  174. */
  175. struct net_device *alloc_fddidev(int sizeof_priv)
  176. {
  177. return alloc_netdev(sizeof_priv, "fddi%d", fddi_setup);
  178. }
  179. EXPORT_SYMBOL(alloc_fddidev);