| /* |
| * Copyright (C) 2013 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 <errno.h> |
| #include <ipxe/dhcppkt.h> |
| #include <ipxe/init.h> |
| #include <ipxe/netdevice.h> |
| #include <ipxe/cachedhcp.h> |
| |
| /** @file |
| * |
| * Cached DHCP packet |
| * |
| */ |
| |
| /** Cached DHCPACK */ |
| static struct dhcp_packet *cached_dhcpack; |
| |
| /** Colour for debug messages */ |
| #define colour &cached_dhcpack |
| |
| /** |
| * Record cached DHCPACK |
| * |
| * @v data DHCPACK packet buffer |
| * @v max_len Maximum possible length |
| * @ret rc Return status code |
| */ |
| int cachedhcp_record ( userptr_t data, size_t max_len ) { |
| struct dhcp_packet *dhcppkt; |
| struct dhcp_packet *tmp; |
| struct dhcphdr *dhcphdr; |
| size_t len; |
| |
| /* Allocate and populate DHCP packet */ |
| dhcppkt = zalloc ( sizeof ( *dhcppkt ) + max_len ); |
| if ( ! dhcppkt ) { |
| DBGC ( colour, "CACHEDHCP could not allocate copy\n" ); |
| return -ENOMEM; |
| } |
| dhcphdr = ( ( ( void * ) dhcppkt ) + sizeof ( *dhcppkt ) ); |
| copy_from_user ( dhcphdr, data, 0, max_len ); |
| dhcppkt_init ( dhcppkt, dhcphdr, max_len ); |
| |
| /* Shrink packet to required length. If reallocation fails, |
| * just continue to use the original packet and waste the |
| * unused space. |
| */ |
| len = dhcppkt_len ( dhcppkt ); |
| assert ( len <= max_len ); |
| tmp = realloc ( dhcppkt, ( sizeof ( *dhcppkt ) + len ) ); |
| if ( tmp ) |
| dhcppkt = tmp; |
| |
| /* Reinitialise packet at new address */ |
| dhcphdr = ( ( ( void * ) dhcppkt ) + sizeof ( *dhcppkt ) ); |
| dhcppkt_init ( dhcppkt, dhcphdr, len ); |
| |
| /* Store as cached DHCPACK, and mark original copy as consumed */ |
| DBGC ( colour, "CACHEDHCP found cached DHCPACK at %#08lx+%#zx/%#zx\n", |
| user_to_phys ( data, 0 ), len, max_len ); |
| cached_dhcpack = dhcppkt; |
| |
| return 0; |
| } |
| |
| /** |
| * Cached DHCPACK startup function |
| * |
| */ |
| static void cachedhcp_startup ( void ) { |
| |
| /* If cached DHCP packet was not claimed by any network device |
| * during startup, then free it. |
| */ |
| if ( cached_dhcpack ) { |
| DBGC ( colour, "CACHEDHCP freeing unclaimed cached DHCPACK\n" ); |
| dhcppkt_put ( cached_dhcpack ); |
| cached_dhcpack = NULL; |
| } |
| } |
| |
| /** Cached DHCPACK startup function */ |
| struct startup_fn cachedhcp_startup_fn __startup_fn ( STARTUP_LATE ) = { |
| .name = "cachedhcp", |
| .startup = cachedhcp_startup, |
| }; |
| |
| /** |
| * Apply cached DHCPACK to network device, if applicable |
| * |
| * @v netdev Network device |
| * @ret rc Return status code |
| */ |
| static int cachedhcp_probe ( struct net_device *netdev ) { |
| struct ll_protocol *ll_protocol = netdev->ll_protocol; |
| int rc; |
| |
| /* Do nothing unless we have a cached DHCPACK */ |
| if ( ! cached_dhcpack ) |
| return 0; |
| |
| /* Do nothing unless cached DHCPACK's MAC address matches this |
| * network device. |
| */ |
| if ( memcmp ( netdev->ll_addr, cached_dhcpack->dhcphdr->chaddr, |
| ll_protocol->ll_addr_len ) != 0 ) { |
| DBGC ( colour, "CACHEDHCP cached DHCPACK does not match %s\n", |
| netdev->name ); |
| return 0; |
| } |
| DBGC ( colour, "CACHEDHCP cached DHCPACK is for %s\n", netdev->name ); |
| |
| /* Register as DHCP settings for this network device */ |
| if ( ( rc = register_settings ( &cached_dhcpack->settings, |
| netdev_settings ( netdev ), |
| DHCP_SETTINGS_NAME ) ) != 0 ) { |
| DBGC ( colour, "CACHEDHCP could not register settings: %s\n", |
| strerror ( rc ) ); |
| return rc; |
| } |
| |
| /* Claim cached DHCPACK */ |
| dhcppkt_put ( cached_dhcpack ); |
| cached_dhcpack = NULL; |
| |
| return 0; |
| } |
| |
| /** Cached DHCP packet network device driver */ |
| struct net_driver cachedhcp_driver __net_driver = { |
| .name = "cachedhcp", |
| .probe = cachedhcp_probe, |
| }; |