MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Route.h

   1 /** @file
   2
   3 Copyright (c) 2005 - 2006, Intel Corporation
   4 All rights reserved. This program and the accompanying materials
   5 are licensed and made available under the terms and conditions of the BSD License
   6 which accompanies this distribution.  The full text of the license may be found at
   7 http://opensource.org/licenses/bsd-license.php
   8
   9 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11
  12
  13 Module Name:
  14
  15   Ip4Route.h
  16
  17 Abstract:
  18
  19   EFI IP4 route table and route cache table defintions.
  20
  21
  22 **/
  23
  24 #ifndef __EFI_IP4_ROUTE_H__
  25 #define __EFI_IP4_ROUTE_H__
  26
  27 #include "Ip4Common.h"
  28
  29 typedef enum {
  30   IP4_DIRECT_ROUTE      = 0x00000001,
  31
  32   IP4_ROUTE_CACHE_HASH  = 31,
  33   IP4_ROUTE_CACHE_MAX   = 64  // Max NO. of cache entry per hash bucket
  34 } IP4_ROUTE_ENUM_TYPES;
  35
  36 #define IP4_ROUTE_CACHE_HASH(Dst, Src)  (((Dst) ^ (Src)) % IP4_ROUTE_CACHE_HASH)
  37
  38 ///
  39 /// The route entry in the route table. Dest/Netmask is the destion
  40 /// network. The nexthop is the gateway to send the packet to in
  41 /// order to reach the Dest/Netmask. If the Flag has IP4_DIRECT_ROUTE
  42 /// on, the gateway is the destination of the IP packet itself. Route
  43 /// enties of the connected network have the flag on.
  44 ///
  45 typedef struct {
  46   LIST_ENTRY                Link;
  47   INTN                      RefCnt;
  48   IP4_ADDR                  Dest;
  49   IP4_ADDR                  Netmask;
  50   IP4_ADDR                  NextHop;
  51   UINT32                    Flag;
  52 } IP4_ROUTE_ENTRY;
  53
  54 ///
  55 /// The route cache entry. The route cache entry is optional.
  56 /// But it is necessary to support the ICMP redirect message.
  57 /// Check Ip4ProcessIcmpRedirect for information.
  58 ///
  59 /// The cache entry field Tag is used to tag all the route
  60 /// cache entry spawned from a route table entry. This makes
  61 /// it simple to delete all the route cache entries from a
  62 /// to-be-deleted route entry.
  63 ///
  64 typedef struct {
  65   LIST_ENTRY                Link;
  66   INTN                      RefCnt;
  67   IP4_ADDR                  Dest;
  68   IP4_ADDR                  Src;
  69   IP4_ADDR                  NextHop;
  70   UINTN                     Tag;
  71 } IP4_ROUTE_CACHE_ENTRY;
  72
  73 ///
  74 /// The route cache table is organized as a hash table. Each
  75 /// IP4 route table has a embedded route cache. For now the
  76 /// route cache and route table are binded togehter. But keep
  77 /// the route cache a seperated structure in case we want to
  78 /// detach them later.
  79 ///
  80 typedef struct {
  81   LIST_ENTRY                CacheBucket[IP4_ROUTE_CACHE_HASH];
  82 } IP4_ROUTE_CACHE;
  83
  84 ///
  85 /// Each IP4 instance has its own route table. Each ServiceBinding
  86 /// instance has a default route table and default address.
  87 ///
  88 /// All the route table entries with the same mask are linked
  89 /// together in one route area. For example, RouteArea[0] contains
  90 /// the default routes. A route table also contains a route cache.
  91 ///
  92 typedef struct _IP4_ROUTE_TABLE IP4_ROUTE_TABLE;
  93
  94 struct _IP4_ROUTE_TABLE {
  95   INTN                      RefCnt;
  96   UINT32                    TotalNum;
  97   LIST_ENTRY                RouteArea[IP4_MASK_NUM];
  98   IP4_ROUTE_TABLE           *Next;
  99   IP4_ROUTE_CACHE           Cache;
 100 };
 101
 102 /**
 103   Create an empty route table, includes its internal route cache
 104
 105   @return NULL if failed to allocate memory for the route table, otherwise
 106           the point to newly created route table.
 107
 108 **/
 109 IP4_ROUTE_TABLE *
 110 Ip4CreateRouteTable (
 111   VOID
 112   );
 113
 114 /**
 115   Free the route table and its associated route cache. Route
 116   table is reference counted.
 117
 118   @param  RtTable               The route table to free.
 119
 120   @return None
 121
 122 **/
 123 VOID
 124 Ip4FreeRouteTable (
 125   IN IP4_ROUTE_TABLE        *RtTable
 126   );
 127
 128 /**
 129   Add a route entry to the route table. All the IP4_ADDRs are in
 130   host byte order.
 131
 132   @param  RtTable               Route table to add route to
 133   @param  Dest                  The destination of the network
 134   @param  Netmask               The netmask of the destination
 135   @param  Gateway               The next hop address
 136
 137   @retval EFI_ACCESS_DENIED     The same route already exists
 138   @retval EFI_OUT_OF_RESOURCES  Failed to allocate memory for the entry
 139   @retval EFI_SUCCESS           The route is added successfully.
 140
 141 **/
 142 EFI_STATUS
 143 Ip4AddRoute (
 144   IN OUT IP4_ROUTE_TABLE        *RtTable,
 145   IN     IP4_ADDR               Dest,
 146   IN     IP4_ADDR               Netmask,
 147   IN     IP4_ADDR               Gateway
 148   );
 149
 150 /**
 151   Remove a route entry and all the route caches spawn from it.
 152
 153   @param  RtTable               The route table to remove the route from
 154   @param  Dest                  The destination network
 155   @param  Netmask               The netmask of the Dest
 156   @param  Gateway               The next hop address
 157
 158   @retval EFI_SUCCESS           The route entry is successfully removed
 159   @retval EFI_NOT_FOUND         There is no route entry in the table with that
 160                                 properity.
 161
 162 **/
 163 EFI_STATUS
 164 Ip4DelRoute (
 165   IN OUT IP4_ROUTE_TABLE      *RtTable,
 166   IN     IP4_ADDR             Dest,
 167   IN     IP4_ADDR             Netmask,
 168   IN     IP4_ADDR             Gateway
 169   );
 170
 171 /**
 172   Find a route cache with the dst and src. This is used by ICMP
 173   redirect messasge process. All kinds of redirect is treated as
 174   host redirect according to RFC1122. So, only route cache entries
 175   are modified according to the ICMP redirect message.
 176
 177   @param  RtTable               The route table to search the cache for
 178   @param  Dest                  The destination address
 179   @param  Src                   The source address
 180
 181   @return NULL if no route entry to the (Dest, Src). Otherwise the point
 182           to the correct route cache entry.
 183
 184 **/
 185 IP4_ROUTE_CACHE_ENTRY *
 186 Ip4FindRouteCache (
 187   IN IP4_ROUTE_TABLE        *RtTable,
 188   IN IP4_ADDR               Dest,
 189   IN IP4_ADDR               Src
 190   );
 191
 192 /**
 193   Free the route cache entry. It is reference counted.
 194
 195   @param  RtCacheEntry          The route cache entry to free.
 196
 197   @return None
 198
 199 **/
 200 VOID
 201 Ip4FreeRouteCacheEntry (
 202   IN IP4_ROUTE_CACHE_ENTRY  *RtCacheEntry
 203   );
 204
 205 /**
 206   Search the route table to route the packet. Return/create a route
 207   cache if there is a route to the destination.
 208
 209   @param  RtTable               The route table to search from
 210   @param  Dest                  The destination address to search for
 211   @param  Src                   The source address to search for
 212
 213   @return NULL if failed to route packet, otherwise a route cache
 214           entry that can be used to route packet.
 215
 216 **/
 217 IP4_ROUTE_CACHE_ENTRY *
 218 Ip4Route (
 219   IN IP4_ROUTE_TABLE        *RtTable,
 220   IN IP4_ADDR               Dest,
 221   IN IP4_ADDR               Src
 222   );
 223
 224 /**
 225   Build a EFI_IP4_ROUTE_TABLE to be returned to the caller of
 226   GetModeData. The EFI_IP4_ROUTE_TABLE is clumsy to use in the
 227   internal operation of the IP4 driver.
 228
 229   @param  IpInstance            The IP4 child that requests the route table.
 230
 231   @retval EFI_SUCCESS           The route table is successfully build
 232   @retval EFI_OUT_OF_RESOURCES  Failed to allocate the memory for the rotue table.
 233
 234 **/
 235 EFI_STATUS
 236 Ip4BuildEfiRouteTable (
 237   IN IP4_PROTOCOL           *IpInstance
 238   );
 239 #endif