+/**\r
+ This worker function sets the DNS server list for the EFI IPv4 network\r
+ stack running on the communication device that this EFI_IP4_CONFIG2_PROTOCOL\r
+ manages. The DNS server addresses must be unicast IPv4 addresses.\r
+\r
+ @param[in] Instance The pointer to the IP4 config2 instance data.\r
+ @param[in] DataSize The size of the buffer pointed to by Data in bytes.\r
+ @param[in] Data The data buffer to set, points to an array of\r
+ EFI_IPv4_ADDRESS instances.\r
+\r
+ @retval EFI_BAD_BUFFER_SIZE The DataSize does not match the size of the type.\r
+ @retval EFI_INVALID_PARAMETER One or more fields in Data is invalid.\r
+ @retval EFI_OUT_OF_RESOURCES Failed to allocate resources to complete the operation.\r
+ @retval EFI_ABORTED The DNS server addresses to be set equal the current\r
+ configuration.\r
+ @retval EFI_SUCCESS The specified configuration data for the EFI IPv4\r
+ network stack was set.\r
+\r
+**/\r
+EFI_STATUS\r
+Ip4Config2SetDnsServerWorker (\r
+ IN IP4_CONFIG2_INSTANCE *Instance,\r
+ IN UINTN DataSize,\r
+ IN VOID *Data\r
+ )\r
+{\r
+ UINTN OldIndex;\r
+ UINTN NewIndex;\r
+ EFI_IPv4_ADDRESS *OldDns;\r
+ EFI_IPv4_ADDRESS *NewDns;\r
+ UINTN OldDnsCount;\r
+ UINTN NewDnsCount;\r
+ IP4_CONFIG2_DATA_ITEM *Item;\r
+ BOOLEAN OneAdded;\r
+ VOID *Tmp;\r
+ IP4_ADDR DnsAddress;\r
+\r
+ if ((DataSize % sizeof (EFI_IPv4_ADDRESS) != 0) || (DataSize == 0)) {\r
+ return EFI_BAD_BUFFER_SIZE;\r
+ }\r
+\r
+ Item = &Instance->DataItem[Ip4Config2DataTypeDnsServer];\r
+ NewDns = (EFI_IPv4_ADDRESS *) Data;\r
+ OldDns = Item->Data.DnsServers;\r
+ NewDnsCount = DataSize / sizeof (EFI_IPv4_ADDRESS);\r
+ OldDnsCount = Item->DataSize / sizeof (EFI_IPv4_ADDRESS);\r
+ OneAdded = FALSE;\r
+\r
+ if (NewDnsCount != OldDnsCount) {\r
+ Tmp = AllocatePool (DataSize);\r
+ if (Tmp == NULL) {\r
+ return EFI_OUT_OF_RESOURCES;\r
+ }\r
+ } else {\r
+ Tmp = NULL;\r
+ }\r
+\r
+ for (NewIndex = 0; NewIndex < NewDnsCount; NewIndex++) {\r
+ CopyMem (&DnsAddress, NewDns + NewIndex, sizeof (IP4_ADDR));\r
+ if (IP4_IS_UNSPECIFIED (NTOHL (DnsAddress)) || IP4_IS_LOCAL_BROADCAST (NTOHL (DnsAddress))) {\r
+ //\r
+ // The dns server address must be unicast.\r
+ //\r
+ if (Tmp != NULL) {\r
+ FreePool (Tmp);\r
+ }\r
+ return EFI_INVALID_PARAMETER;\r
+ }\r
+\r
+ if (OneAdded) {\r
+ //\r
+ // If any address in the new setting is not in the old settings, skip the\r
+ // comparision below.\r
+ //\r
+ continue;\r
+ }\r
+\r
+ for (OldIndex = 0; OldIndex < OldDnsCount; OldIndex++) {\r
+ if (EFI_IP4_EQUAL (NewDns + NewIndex, OldDns + OldIndex)) {\r
+ //\r
+ // If found break out.\r
+ //\r
+ break;\r
+ }\r
+ }\r
+\r
+ if (OldIndex == OldDnsCount) {\r
+ OneAdded = TRUE;\r
+ }\r
+ }\r
+\r
+ if (!OneAdded && (DataSize == Item->DataSize)) {\r
+ //\r
+ // No new item is added and the size is the same.\r
+ //\r
+ Item->Status = EFI_SUCCESS;\r
+ return EFI_ABORTED;\r
+ } else {\r
+ if (Tmp != NULL) {\r
+ if (Item->Data.Ptr != NULL) {\r
+ FreePool (Item->Data.Ptr);\r
+ }\r
+ Item->Data.Ptr = Tmp;\r
+ }\r
+\r
+ CopyMem (Item->Data.Ptr, Data, DataSize);\r
+ Item->DataSize = DataSize;\r
+ Item->Status = EFI_SUCCESS;\r
+ return EFI_SUCCESS;\r
+ }\r
+}\r
+\r
+\r