1 /* 2 * Copyright (C) 2009 Joshua Oreman <oremanj (at) rwcr.net>. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License as 6 * published by the Free Software Foundation; either version 2 of the 7 * License, or any later version. 8 * 9 * This program is distributed in the hope that it will be useful, but 10 * WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 * General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 17 */ 18 19 FILE_LICENCE ( GPL2_OR_LATER ); 20 21 #include <string.h> 22 #include <gpxe/dhcp.h> 23 #include <gpxe/netdevice.h> 24 #include <undipreload.h> 25 #include <pxeparent.h> 26 #include <realmode.h> 27 #include <pxe_api.h> 28 29 /** 30 * Present cached DHCP packet if it exists 31 */ 32 void __weak_impl ( get_cached_dhcpack ) ( void ) { 33 struct undi_device *undi; 34 struct s_PXENV_GET_CACHED_INFO get_cached_info; 35 int rc; 36 37 /* Use preloaded UNDI device to get at PXE entry point */ 38 undi = &preloaded_undi; 39 if ( ! undi->entry.segment ) { 40 DBG ( "PXEDHCP no preloaded UNDI device found\n" ); 41 return; 42 } 43 44 /* Check that stack is available to get cached info */ 45 if ( ! ( undi->flags & UNDI_FL_KEEP_ALL ) ) { 46 DBG ( "PXEDHCP stack was unloaded, no cache available\n" ); 47 return; 48 } 49 50 /* Obtain cached DHCP packet */ 51 memset ( &get_cached_info, 0, sizeof ( get_cached_info ) ); 52 get_cached_info.PacketType = PXENV_PACKET_TYPE_DHCP_ACK; 53 54 if ( ( rc = pxeparent_call ( undi->entry, PXENV_GET_CACHED_INFO, 55 &get_cached_info, 56 sizeof ( get_cached_info ) ) ) != 0 ) { 57 DBG ( "PXEDHCP GET_CACHED_INFO failed: %s\n", strerror ( rc ) ); 58 return; 59 } 60 61 DBG ( "PXEDHCP got cached info at %04x:%04x length %d\n", 62 get_cached_info.Buffer.segment, get_cached_info.Buffer.offset, 63 get_cached_info.BufferSize ); 64 65 /* Present cached DHCP packet */ 66 store_cached_dhcpack ( real_to_user ( get_cached_info.Buffer.segment, 67 get_cached_info.Buffer.offset ), 68 get_cached_info.BufferSize ); 69 } 70