diff options
Diffstat (limited to 'src/VBox/Devices/PC/ipxe/src/net/fakedhcp.c')
| -rw-r--r-- | src/VBox/Devices/PC/ipxe/src/net/fakedhcp.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/src/VBox/Devices/PC/ipxe/src/net/fakedhcp.c b/src/VBox/Devices/PC/ipxe/src/net/fakedhcp.c new file mode 100644 index 00000000..009b12c5 --- /dev/null +++ b/src/VBox/Devices/PC/ipxe/src/net/fakedhcp.c @@ -0,0 +1,223 @@ +/* + * Copyright (C) 2008 Michael Brown <mbrown@fensystems.co.uk>. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of the + * License, or any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + * + * You can also choose to distribute this program under the terms of + * the Unmodified Binary Distribution Licence (as given in the file + * COPYING.UBDL), provided that you have satisfied its requirements. + */ + +FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ); + +#include <stdint.h> +#include <stdlib.h> +#include <stdio.h> +#include <errno.h> +#include <string.h> +#include <ipxe/settings.h> +#include <ipxe/netdevice.h> +#include <ipxe/dhcppkt.h> +#include <ipxe/fakedhcp.h> + +/** @file + * + * Fake DHCP packets + * + */ + +/** + * Copy settings to DHCP packet + * + * @v dest Destination DHCP packet + * @v source Source settings block + * @v encapsulator Encapsulating setting tag number, or zero + * @ret rc Return status code + */ +static int copy_encap_settings ( struct dhcp_packet *dest, + struct settings *source, + unsigned int encapsulator ) { + struct setting setting = { .name = "" }; + unsigned int subtag; + unsigned int tag; + void *data; + int len; + int rc; + + for ( subtag = DHCP_MIN_OPTION; subtag <= DHCP_MAX_OPTION; subtag++ ) { + tag = DHCP_ENCAP_OPT ( encapsulator, subtag ); + switch ( tag ) { + case DHCP_EB_ENCAP: + case DHCP_VENDOR_ENCAP: + /* Process encapsulated settings */ + if ( ( rc = copy_encap_settings ( dest, source, + tag ) ) != 0 ) + return rc; + break; + default: + /* Copy setting, if present */ + setting.tag = tag; + len = fetch_raw_setting_copy ( source, &setting, &data); + if ( len >= 0 ) { + rc = dhcppkt_store ( dest, tag, data, len ); + free ( data ); + if ( rc != 0 ) + return rc; + } + break; + } + } + + return 0; +} + +/** + * Copy settings to DHCP packet + * + * @v dest Destination DHCP packet + * @v source Source settings block + * @ret rc Return status code + */ +static int copy_settings ( struct dhcp_packet *dest, + struct settings *source ) { + return copy_encap_settings ( dest, source, 0 ); +} + +/** + * Create fake DHCPDISCOVER packet + * + * @v netdev Network device + * @v data Buffer for DHCP packet + * @v max_len Size of DHCP packet buffer + * @ret rc Return status code + * + * Used by external code. + */ +int create_fakedhcpdiscover ( struct net_device *netdev, + void *data, size_t max_len ) { + struct dhcp_packet dhcppkt; + struct in_addr ciaddr = { 0 }; + int rc; + + if ( ( rc = dhcp_create_request ( &dhcppkt, netdev, DHCPDISCOVER, + dhcp_last_xid, ciaddr, data, + max_len ) ) != 0 ) { + DBG ( "Could not create DHCPDISCOVER: %s\n", + strerror ( rc ) ); + return rc; + } + + return 0; +} + +/** + * Create fake DHCPACK packet + * + * @v netdev Network device + * @v data Buffer for DHCP packet + * @v max_len Size of DHCP packet buffer + * @ret rc Return status code + * + * Used by external code. + */ +int create_fakedhcpack ( struct net_device *netdev, + void *data, size_t max_len ) { + struct dhcp_packet dhcppkt; + int rc; + + /* Create base DHCPACK packet */ + if ( ( rc = dhcp_create_packet ( &dhcppkt, netdev, DHCPACK, + dhcp_last_xid, NULL, 0, + data, max_len ) ) != 0 ) { + DBG ( "Could not create DHCPACK: %s\n", strerror ( rc ) ); + return rc; + } + + /* Merge in globally-scoped settings, then netdev-specific + * settings. Do it in this order so that netdev-specific + * settings take precedence regardless of stated priorities. + */ + if ( ( rc = copy_settings ( &dhcppkt, NULL ) ) != 0 ) { + DBG ( "Could not set DHCPACK global settings: %s\n", + strerror ( rc ) ); + return rc; + } + if ( ( rc = copy_settings ( &dhcppkt, + netdev_settings ( netdev ) ) ) != 0 ) { + DBG ( "Could not set DHCPACK netdev settings: %s\n", + strerror ( rc ) ); + return rc; + } + + return 0; +} + +/** + * Create fake PXE Boot Server ACK packet + * + * @v netdev Network device + * @v data Buffer for DHCP packet + * @v max_len Size of DHCP packet buffer + * @ret rc Return status code + * + * Used by external code. + */ +int create_fakepxebsack ( struct net_device *netdev, + void *data, size_t max_len ) { + struct dhcp_packet dhcppkt; + struct settings *proxy_settings; + struct settings *pxebs_settings; + int rc; + + /* Identify available settings */ + proxy_settings = find_settings ( PROXYDHCP_SETTINGS_NAME ); + pxebs_settings = find_settings ( PXEBS_SETTINGS_NAME ); + if ( ( ! proxy_settings ) && ( ! pxebs_settings ) ) { + /* No PXE boot server; return the regular DHCPACK */ + return create_fakedhcpack ( netdev, data, max_len ); + } + + /* Create base DHCPACK packet */ + if ( ( rc = dhcp_create_packet ( &dhcppkt, netdev, DHCPACK, + dhcp_last_xid, NULL, 0, + data, max_len ) ) != 0 ) { + DBG ( "Could not create PXE BS ACK: %s\n", + strerror ( rc ) ); + return rc; + } + + /* Populate ciaddr */ + fetch_ipv4_setting ( netdev_settings ( netdev ), &ip_setting, + &dhcppkt.dhcphdr->ciaddr ); + + /* Merge in ProxyDHCP options */ + if ( proxy_settings && + ( ( rc = copy_settings ( &dhcppkt, proxy_settings ) ) != 0 ) ) { + DBG ( "Could not copy ProxyDHCP settings: %s\n", + strerror ( rc ) ); + return rc; + } + + /* Merge in BootServerDHCP options, if present */ + if ( pxebs_settings && + ( ( rc = copy_settings ( &dhcppkt, pxebs_settings ) ) != 0 ) ) { + DBG ( "Could not copy PXE BS settings: %s\n", + strerror ( rc ) ); + return rc; + } + + return 0; +} |