1 /** @file 2 EFI IP4 route table and route cache table definitions. 3 4 Copyright (c) 2005 - 2018, Intel Corporation. All rights reserved.<BR> 5 SPDX-License-Identifier: BSD-2-Clause-Patent 6 7 **/ 8 9 #ifndef __EFI_IP4_ROUTE_H__ 10 #define __EFI_IP4_ROUTE_H__ 11 12 #include "Ip4Common.h" 13 14 #define IP4_DIRECT_ROUTE 0x00000001 15 16 #define IP4_ROUTE_CACHE_HASH_VALUE 31 17 #define IP4_ROUTE_CACHE_MAX 64 // Max NO. of cache entry per hash bucket 18 19 #define IP4_ROUTE_CACHE_HASH(Dst, Src) (((Dst) ^ (Src)) % IP4_ROUTE_CACHE_HASH_VALUE) 20 21 /// 22 /// The route entry in the route table. Dest/Netmask is the destion 23 /// network. The nexthop is the gateway to send the packet to in 24 /// order to reach the Dest/Netmask. If the Flag has IP4_DIRECT_ROUTE 25 /// on, the gateway is the destination of the IP packet itself. Route 26 /// enties of the connected network have the flag on. 27 /// 28 typedef struct { 29 LIST_ENTRY Link; 30 INTN RefCnt; 31 IP4_ADDR Dest; 32 IP4_ADDR Netmask; 33 IP4_ADDR NextHop; 34 UINT32 Flag; 35 } IP4_ROUTE_ENTRY; 36 37 /// 38 /// The route cache entry. The route cache entry is optional. 39 /// But it is necessary to support the ICMP redirect message. 40 /// Check Ip4ProcessIcmpRedirect for information. 41 /// 42 /// The cache entry field Tag is used to tag all the route 43 /// cache entry spawned from a route table entry. This makes 44 /// it simple to delete all the route cache entries from a 45 /// to-be-deleted route entry. 46 /// 47 typedef struct { 48 LIST_ENTRY Link; 49 INTN RefCnt; 50 IP4_ADDR Dest; 51 IP4_ADDR Src; 52 IP4_ADDR NextHop; 53 UINTN Tag; 54 } IP4_ROUTE_CACHE_ENTRY; 55 56 /// 57 /// The route cache table is organized as a hash table. Each 58 /// IP4 route table has a embedded route cache. For now the 59 /// route cache and route table are binded together. But keep 60 /// the route cache a separated structure in case we want to 61 /// detach them later. 62 /// 63 typedef struct { 64 LIST_ENTRY CacheBucket[IP4_ROUTE_CACHE_HASH_VALUE]; 65 } IP4_ROUTE_CACHE; 66 67 /// 68 /// Each IP4 instance has its own route table. Each ServiceBinding 69 /// instance has a default route table and default address. 70 /// 71 /// All the route table entries with the same mask are linked 72 /// together in one route area. For example, RouteArea[0] contains 73 /// the default routes. A route table also contains a route cache. 74 /// 75 typedef struct _IP4_ROUTE_TABLE IP4_ROUTE_TABLE; 76 77 struct _IP4_ROUTE_TABLE { 78 INTN RefCnt; 79 UINT32 TotalNum; 80 LIST_ENTRY RouteArea[IP4_MASK_NUM]; 81 IP4_ROUTE_TABLE *Next; 82 IP4_ROUTE_CACHE Cache; 83 }; 84 85 /** 86 Create an empty route table, includes its internal route cache 87 88 @return NULL if failed to allocate memory for the route table, otherwise 89 the point to newly created route table. 90 91 **/ 92 IP4_ROUTE_TABLE * 93 Ip4CreateRouteTable ( 94 VOID 95 ); 96 97 /** 98 Free the route table and its associated route cache. Route 99 table is reference counted. 100 101 @param[in] RtTable The route table to free. 102 103 **/ 104 VOID 105 Ip4FreeRouteTable ( 106 IN IP4_ROUTE_TABLE *RtTable 107 ); 108 109 /** 110 Add a route entry to the route table. All the IP4_ADDRs are in 111 host byte order. 112 113 @param[in, out] RtTable Route table to add route to 114 @param[in] Dest The destination of the network 115 @param[in] Netmask The netmask of the destination 116 @param[in] Gateway The next hop address 117 118 @retval EFI_ACCESS_DENIED The same route already exists 119 @retval EFI_OUT_OF_RESOURCES Failed to allocate memory for the entry 120 @retval EFI_SUCCESS The route is added successfully. 121 122 **/ 123 EFI_STATUS 124 Ip4AddRoute ( 125 IN OUT IP4_ROUTE_TABLE *RtTable, 126 IN IP4_ADDR Dest, 127 IN IP4_ADDR Netmask, 128 IN IP4_ADDR Gateway 129 ); 130 131 /** 132 Remove a route entry and all the route caches spawn from it. 133 134 @param RtTable The route table to remove the route from 135 @param Dest The destination network 136 @param Netmask The netmask of the Dest 137 @param Gateway The next hop address 138 139 @retval EFI_SUCCESS The route entry is successfully removed 140 @retval EFI_NOT_FOUND There is no route entry in the table with that 141 property. 142 143 **/ 144 EFI_STATUS 145 Ip4DelRoute ( 146 IN OUT IP4_ROUTE_TABLE *RtTable, 147 IN IP4_ADDR Dest, 148 IN IP4_ADDR Netmask, 149 IN IP4_ADDR Gateway 150 ); 151 152 /** 153 Find a route cache with the dst and src. This is used by ICMP 154 redirect message process. All kinds of redirect is treated as 155 host redirect according to RFC1122. So, only route cache entries 156 are modified according to the ICMP redirect message. 157 158 @param[in] RtTable The route table to search the cache for 159 @param[in] Dest The destination address 160 @param[in] Src The source address 161 162 @return NULL if no route entry to the (Dest, Src). Otherwise the point 163 to the correct route cache entry. 164 165 **/ 166 IP4_ROUTE_CACHE_ENTRY * 167 Ip4FindRouteCache ( 168 IN IP4_ROUTE_TABLE *RtTable, 169 IN IP4_ADDR Dest, 170 IN IP4_ADDR Src 171 ); 172 173 /** 174 Free the route cache entry. It is reference counted. 175 176 @param RtCacheEntry The route cache entry to free. 177 178 **/ 179 VOID 180 Ip4FreeRouteCacheEntry ( 181 IN IP4_ROUTE_CACHE_ENTRY *RtCacheEntry 182 ); 183 184 /** 185 Search the route table to route the packet. Return/create a route 186 cache if there is a route to the destination. 187 188 @param[in] RtTable The route table to search from 189 @param[in] Dest The destination address to search for 190 @param[in] Src The source address to search for 191 @param[in] SubnetMask The subnet mask of the Src address, this field is 192 used to check if the station is using /32 subnet. 193 @param[in] AlwaysTryDestAddr Always try to use the dest address as next hop even 194 though we can't find a matching route entry. This 195 field is only valid when using /32 subnet. 196 197 @return NULL if failed to route packet, otherwise a route cache 198 entry that can be used to route packet. 199 200 **/ 201 IP4_ROUTE_CACHE_ENTRY * 202 Ip4Route ( 203 IN IP4_ROUTE_TABLE *RtTable, 204 IN IP4_ADDR Dest, 205 IN IP4_ADDR Src, 206 IN IP4_ADDR SubnetMask, 207 IN BOOLEAN AlwaysTryDestAddr 208 ); 209 210 /** 211 Build a EFI_IP4_ROUTE_TABLE to be returned to the caller of 212 GetModeData. The EFI_IP4_ROUTE_TABLE is clumsy to use in the 213 internal operation of the IP4 driver. 214 215 @param[in] IpInstance The IP4 child that requests the route table. 216 217 @retval EFI_SUCCESS The route table is successfully build 218 @retval EFI_OUT_OF_RESOURCES Failed to allocate the memory for the route table. 219 220 **/ 221 EFI_STATUS 222 Ip4BuildEfiRouteTable ( 223 IN IP4_PROTOCOL *IpInstance 224 ); 225 #endif 226