diff options
Diffstat (limited to 'gpxe/src/net/udp/dhcp.c')
| -rw-r--r-- | gpxe/src/net/udp/dhcp.c | 1587 |
1 files changed, 0 insertions, 1587 deletions
diff --git a/gpxe/src/net/udp/dhcp.c b/gpxe/src/net/udp/dhcp.c deleted file mode 100644 index ce2c8207..00000000 --- a/gpxe/src/net/udp/dhcp.c +++ /dev/null @@ -1,1587 +0,0 @@ -/* - * Copyright (C) 2006 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., 675 Mass Ave, Cambridge, MA 02139, USA. - */ - -FILE_LICENCE ( GPL2_OR_LATER ); - -#include <string.h> -#include <stdlib.h> -#include <stdio.h> -#include <ctype.h> -#include <errno.h> -#include <assert.h> -#include <byteswap.h> -#include <gpxe/if_ether.h> -#include <gpxe/netdevice.h> -#include <gpxe/device.h> -#include <gpxe/xfer.h> -#include <gpxe/open.h> -#include <gpxe/job.h> -#include <gpxe/retry.h> -#include <gpxe/tcpip.h> -#include <gpxe/ip.h> -#include <gpxe/uuid.h> -#include <gpxe/timer.h> -#include <gpxe/settings.h> -#include <gpxe/dhcp.h> -#include <gpxe/dhcpopts.h> -#include <gpxe/dhcppkt.h> -#include <gpxe/features.h> - -/** @file - * - * Dynamic Host Configuration Protocol - * - */ - -struct dhcp_session; -static int dhcp_tx ( struct dhcp_session *dhcp ); - -/** - * DHCP operation types - * - * This table maps from DHCP message types (i.e. values of the @c - * DHCP_MESSAGE_TYPE option) to values of the "op" field within a DHCP - * packet. - */ -static const uint8_t dhcp_op[] = { - [DHCPDISCOVER] = BOOTP_REQUEST, - [DHCPOFFER] = BOOTP_REPLY, - [DHCPREQUEST] = BOOTP_REQUEST, - [DHCPDECLINE] = BOOTP_REQUEST, - [DHCPACK] = BOOTP_REPLY, - [DHCPNAK] = BOOTP_REPLY, - [DHCPRELEASE] = BOOTP_REQUEST, - [DHCPINFORM] = BOOTP_REQUEST, -}; - -/** Raw option data for options common to all DHCP requests */ -static uint8_t dhcp_request_options_data[] = { - DHCP_MESSAGE_TYPE, DHCP_BYTE ( 0 ), - DHCP_MAX_MESSAGE_SIZE, - DHCP_WORD ( ETH_MAX_MTU - 20 /* IP header */ - 8 /* UDP header */ ), - DHCP_CLIENT_ARCHITECTURE, DHCP_WORD ( 0 ), - DHCP_CLIENT_NDI, DHCP_OPTION ( 1 /* UNDI */ , 2, 1 /* v2.1 */ ), - DHCP_VENDOR_CLASS_ID, - DHCP_STRING ( 'P', 'X', 'E', 'C', 'l', 'i', 'e', 'n', 't', ':', - 'A', 'r', 'c', 'h', ':', '0', '0', '0', '0', '0', ':', - 'U', 'N', 'D', 'I', ':', '0', '0', '2', '0', '0', '1' ), - DHCP_USER_CLASS_ID, - DHCP_STRING ( 'g', 'P', 'X', 'E' ), - DHCP_PARAMETER_REQUEST_LIST, - DHCP_OPTION ( DHCP_SUBNET_MASK, DHCP_ROUTERS, DHCP_DNS_SERVERS, - DHCP_LOG_SERVERS, DHCP_HOST_NAME, DHCP_DOMAIN_NAME, - DHCP_ROOT_PATH, DHCP_VENDOR_ENCAP, DHCP_VENDOR_CLASS_ID, - DHCP_TFTP_SERVER_NAME, DHCP_BOOTFILE_NAME, - DHCP_EB_ENCAP, DHCP_ISCSI_INITIATOR_IQN ), - DHCP_END -}; - -/** Version number feature */ -FEATURE_VERSION ( VERSION_MAJOR, VERSION_MINOR, VERSION_PATCH ); - -/** DHCP server address setting */ -struct setting dhcp_server_setting __setting = { - .name = "dhcp-server", - .description = "DHCP server address", - .tag = DHCP_SERVER_IDENTIFIER, - .type = &setting_type_ipv4, -}; - -/** DHCP user class setting */ -struct setting user_class_setting __setting = { - .name = "user-class", - .description = "User class identifier", - .tag = DHCP_USER_CLASS_ID, - .type = &setting_type_string, -}; - -/** Use cached network settings */ -struct setting use_cached_setting __setting = { - .name = "use-cached", - .description = "Use cached network settings", - .tag = DHCP_EB_USE_CACHED, - .type = &setting_type_uint8, -}; - -/** - * Name a DHCP packet type - * - * @v msgtype DHCP message type - * @ret string DHCP mesasge type name - */ -static inline const char * dhcp_msgtype_name ( unsigned int msgtype ) { - switch ( msgtype ) { - case DHCPNONE: return "BOOTP"; /* Non-DHCP packet */ - case DHCPDISCOVER: return "DHCPDISCOVER"; - case DHCPOFFER: return "DHCPOFFER"; - case DHCPREQUEST: return "DHCPREQUEST"; - case DHCPDECLINE: return "DHCPDECLINE"; - case DHCPACK: return "DHCPACK"; - case DHCPNAK: return "DHCPNAK"; - case DHCPRELEASE: return "DHCPRELEASE"; - case DHCPINFORM: return "DHCPINFORM"; - default: return "DHCP<invalid>"; - } -} - -/** - * Calculate DHCP transaction ID for a network device - * - * @v netdev Network device - * @ret xid DHCP XID - * - * Extract the least significant bits of the hardware address for use - * as the transaction ID. - */ -static uint32_t dhcp_xid ( struct net_device *netdev ) { - uint32_t xid; - - memcpy ( &xid, ( netdev->ll_addr + netdev->ll_protocol->ll_addr_len - - sizeof ( xid ) ), sizeof ( xid ) ); - return xid; -} - -/**************************************************************************** - * - * DHCP session - * - */ - -struct dhcp_session; - -/** DHCP session state operations */ -struct dhcp_session_state { - /** State name */ - const char *name; - /** - * Construct transmitted packet - * - * @v dhcp DHCP session - * @v dhcppkt DHCP packet - * @v peer Destination address - */ - int ( * tx ) ( struct dhcp_session *dhcp, - struct dhcp_packet *dhcppkt, - struct sockaddr_in *peer ); - /** Handle received packet - * - * @v dhcp DHCP session - * @v dhcppkt DHCP packet - * @v peer DHCP server address - * @v msgtype DHCP message type - * @v server_id DHCP server ID - */ - void ( * rx ) ( struct dhcp_session *dhcp, - struct dhcp_packet *dhcppkt, - struct sockaddr_in *peer, - uint8_t msgtype, struct in_addr server_id ); - /** Handle timer expiry - * - * @v dhcp DHCP session - */ - void ( * expired ) ( struct dhcp_session *dhcp ); - /** Transmitted message type */ - uint8_t tx_msgtype; - /** Apply minimum timeout */ - uint8_t apply_min_timeout; -}; - -static struct dhcp_session_state dhcp_state_discover; -static struct dhcp_session_state dhcp_state_request; -static struct dhcp_session_state dhcp_state_proxy; -static struct dhcp_session_state dhcp_state_pxebs; - -/** DHCP offer is valid for IP lease */ -#define DHCP_OFFER_IP 1 - -/** DHCP offer is valid for PXE options */ -#define DHCP_OFFER_PXE 2 - -/** A DHCP offer */ -struct dhcp_offer { - /** IP address of server granting offer */ - struct in_addr server; - - /** IP address being offered, or 0.0.0.0 for a pure proxy */ - struct in_addr ip; - - /** DHCP packet containing PXE options; NULL if missing or proxied */ - struct dhcp_packet *pxe; - - /** Valid uses for this offer, a combination of DHCP_OFFER bits */ - uint8_t valid; - - /** Priority of this offer */ - int8_t priority; - - /** Whether to ignore PXE DHCP extensions */ - uint8_t no_pxedhcp; -}; - -/** Maximum number of DHCP offers to queue */ -#define DHCP_MAX_OFFERS 6 - -/** A DHCP session */ -struct dhcp_session { - /** Reference counter */ - struct refcnt refcnt; - /** Job control interface */ - struct job_interface job; - /** Data transfer interface */ - struct xfer_interface xfer; - - /** Network device being configured */ - struct net_device *netdev; - /** Local socket address */ - struct sockaddr_in local; - /** State of the session */ - struct dhcp_session_state *state; - - /** PXE Boot Server type */ - uint16_t pxe_type; - /** List of PXE Boot Servers to attempt */ - struct in_addr *pxe_attempt; - /** List of PXE Boot Servers to accept */ - struct in_addr *pxe_accept; - - /** Retransmission timer */ - struct retry_timer timer; - /** Start time of the current state (in ticks) */ - unsigned long start; - - /** DHCP offer just requested */ - struct dhcp_offer *current_offer; - /** List of DHCP offers received */ - struct dhcp_offer offers[DHCP_MAX_OFFERS]; -}; - -/** - * Free DHCP session - * - * @v refcnt Reference counter - */ -static void dhcp_free ( struct refcnt *refcnt ) { - struct dhcp_session *dhcp = - container_of ( refcnt, struct dhcp_session, refcnt ); - int i; - - for ( i = 0 ; i < DHCP_MAX_OFFERS ; i++ ) { - if ( dhcp->offers[i].pxe ) - dhcppkt_put ( dhcp->offers[i].pxe ); - } - - netdev_put ( dhcp->netdev ); - free ( dhcp ); -} - -/** - * Mark DHCP session as complete - * - * @v dhcp DHCP session - * @v rc Return status code - */ -static void dhcp_finished ( struct dhcp_session *dhcp, int rc ) { - - /* Block futher incoming messages */ - job_nullify ( &dhcp->job ); - xfer_nullify ( &dhcp->xfer ); - - /* Stop retry timer */ - stop_timer ( &dhcp->timer ); - - /* Free resources and close interfaces */ - xfer_close ( &dhcp->xfer, rc ); - job_done ( &dhcp->job, rc ); -} - -/** - * Transition to new DHCP session state - * - * @v dhcp DHCP session - * @v state New session state - */ -static void dhcp_set_state ( struct dhcp_session *dhcp, - struct dhcp_session_state *state ) { - - DBGC ( dhcp, "DHCP %p entering %s state\n", dhcp, state->name ); - dhcp->state = state; - dhcp->start = currticks(); - stop_timer ( &dhcp->timer ); - dhcp->timer.min_timeout = - ( state->apply_min_timeout ? DHCP_MIN_TIMEOUT : 0 ); - dhcp->timer.max_timeout = DHCP_MAX_TIMEOUT; - start_timer_nodelay ( &dhcp->timer ); -} - -/** - * Determine next DHCP offer to try - * - * @v dhcp DHCP session - * @v type DHCP offer type - * @ret offer Next DHCP offer to try - * - * Offers are ranked by priority, then by completeness (combined - * IP+PXE are tried before @a type alone), then by order of receipt. - */ -static struct dhcp_offer * dhcp_next_offer ( struct dhcp_session *dhcp, - uint8_t type ) { - - struct dhcp_offer *offer; - struct dhcp_offer *best = NULL; - - for ( offer = dhcp->offers ; offer < dhcp->offers + DHCP_MAX_OFFERS ; - offer++ ) { - if ( ( offer->valid & type ) && - ( ( best == NULL ) || - ( offer->priority > best->priority ) || - ( ( offer->priority == best->priority ) && - ( offer->valid & ~best->valid ) ) ) ) - best = offer; - } - - return best; -} - -/**************************************************************************** - * - * DHCP state machine - * - */ - -/** - * Construct transmitted packet for DHCP discovery - * - * @v dhcp DHCP session - * @v dhcppkt DHCP packet - * @v peer Destination address - */ -static int dhcp_discovery_tx ( struct dhcp_session *dhcp, - struct dhcp_packet *dhcppkt __unused, - struct sockaddr_in *peer ) { - - DBGC ( dhcp, "DHCP %p DHCPDISCOVER\n", dhcp ); - - /* Set server address */ - peer->sin_addr.s_addr = INADDR_BROADCAST; - peer->sin_port = htons ( BOOTPS_PORT ); - - return 0; -} - -/** - * Handle received DHCPOFFER during any state - * - * @v dhcp DHCP session - * @v dhcppkt DHCP packet - * @v peer DHCP server address - * @v msgtype DHCP message type - * @v server_id DHCP server ID - */ -static void dhcp_rx_offer ( struct dhcp_session *dhcp, - struct dhcp_packet *dhcppkt, - struct sockaddr_in *peer, uint8_t msgtype, - struct in_addr server_id ) { - char vci[9]; /* "PXEClient" */ - int vci_len; - int has_pxeclient; - int pxeopts_len; - int has_pxeopts; - struct dhcp_offer *offer; - int i; - - DBGC ( dhcp, "DHCP %p %s from %s:%d", dhcp, - dhcp_msgtype_name ( msgtype ), inet_ntoa ( peer->sin_addr ), - ntohs ( peer->sin_port ) ); - if ( server_id.s_addr != peer->sin_addr.s_addr ) - DBGC ( dhcp, " (%s)", inet_ntoa ( server_id ) ); - - /* Identify offered IP address */ - if ( dhcppkt->dhcphdr->yiaddr.s_addr ) - DBGC ( dhcp, " for %s", inet_ntoa ( dhcppkt->dhcphdr->yiaddr )); - - /* Enqueue an offer to be filled in */ - for ( i = 0 ; i < DHCP_MAX_OFFERS ; i++ ) { - if ( dhcp->offers[i].server.s_addr == server_id.s_addr ) { - DBGC ( dhcp, " dup\n" ); - return; - } - - if ( ! dhcp->offers[i].valid ) - break; - } - if ( i == DHCP_MAX_OFFERS ) { - DBGC ( dhcp, " dropped\n" ); - return; - } - - offer = &dhcp->offers[i]; - offer->server = server_id; - offer->ip = dhcppkt->dhcphdr->yiaddr; - - /* Identify "PXEClient" vendor class */ - vci_len = dhcppkt_fetch ( dhcppkt, DHCP_VENDOR_CLASS_ID, - vci, sizeof ( vci ) ); - has_pxeclient = ( ( vci_len >= ( int ) sizeof ( vci ) ) && - ( strncmp ( "PXEClient", vci, sizeof (vci) ) == 0 )); - - /* Identify presence of PXE-specific options */ - pxeopts_len = dhcppkt_fetch ( dhcppkt, DHCP_PXE_BOOT_MENU, NULL, 0 ); - has_pxeopts = ( pxeopts_len >= 0 ); - if ( has_pxeclient ) - DBGC ( dhcp, "%s", ( has_pxeopts ? " pxe" : " proxy" ) ); - - if ( has_pxeclient && has_pxeopts ) { - /* Save reference to packet for future use */ - if ( offer->pxe ) - dhcppkt_put ( offer->pxe ); - offer->pxe = dhcppkt_get ( dhcppkt ); - } - - /* Identify priority */ - dhcppkt_fetch ( dhcppkt, DHCP_EB_PRIORITY, &offer->priority, - sizeof ( offer->priority ) ); - if ( offer->priority ) - DBGC ( dhcp, " pri %d", offer->priority ); - - /* Identify ignore-PXE flag */ - dhcppkt_fetch ( dhcppkt, DHCP_EB_NO_PXEDHCP, &offer->no_pxedhcp, - sizeof ( offer->no_pxedhcp ) ); - if ( offer->no_pxedhcp ) - DBGC ( dhcp, " nopxe" ); - DBGC ( dhcp, "\n" ); - - /* Determine roles this offer can fill */ - if ( offer->ip.s_addr && - ( peer->sin_port == htons ( BOOTPS_PORT ) ) && - ( ( msgtype == DHCPOFFER ) || ( ! msgtype /* BOOTP */ ) ) ) - offer->valid |= DHCP_OFFER_IP; - - if ( has_pxeclient && ( msgtype == DHCPOFFER ) ) - offer->valid |= DHCP_OFFER_PXE; -} - -/** - * Handle received packet during DHCP discovery - * - * @v dhcp DHCP session - * @v dhcppkt DHCP packet - * @v peer DHCP server address - * @v msgtype DHCP message type - * @v server_id DHCP server ID - */ -static void dhcp_discovery_rx ( struct dhcp_session *dhcp, - struct dhcp_packet *dhcppkt, - struct sockaddr_in *peer, uint8_t msgtype, - struct in_addr server_id ) { - unsigned long elapsed; - struct dhcp_offer *ip_offer; - - dhcp_rx_offer ( dhcp, dhcppkt, peer, msgtype, server_id ); - - /* We can exit the discovery state when we have a valid - * DHCPOFFER, and either: - * - * o The DHCPOFFER instructs us to ignore ProxyDHCPOFFERs, or - * o We have a valid ProxyDHCPOFFER, or - * o We have allowed sufficient time for ProxyDHCPOFFERs. - */ - - /* If we don't yet have a DHCPOFFER, do nothing */ - ip_offer = dhcp_next_offer ( dhcp, DHCP_OFFER_IP ); - if ( ! ip_offer ) - return; - - /* If we can't yet transition to DHCPREQUEST, do nothing */ - elapsed = ( currticks() - dhcp->start ); - if ( ! ( ip_offer->no_pxedhcp || - dhcp_next_offer ( dhcp, DHCP_OFFER_PXE ) || - ( elapsed > PROXYDHCP_MAX_TIMEOUT ) ) ) - return; - - /* Transition to DHCPREQUEST */ - dhcp_set_state ( dhcp, &dhcp_state_request ); -} - -/** - * Handle timer expiry during DHCP discovery - * - * @v dhcp DHCP session - */ -static void dhcp_discovery_expired ( struct dhcp_session *dhcp ) { - unsigned long elapsed = ( currticks() - dhcp->start ); - - /* Give up waiting for ProxyDHCP before we reach the failure point */ - if ( dhcp_next_offer ( dhcp, DHCP_OFFER_IP ) && - ( elapsed > PROXYDHCP_MAX_TIMEOUT ) ) { - dhcp_set_state ( dhcp, &dhcp_state_request ); - return; - } - - /* Otherwise, retransmit current packet */ - dhcp_tx ( dhcp ); -} - -/** DHCP discovery state operations */ -static struct dhcp_session_state dhcp_state_discover = { - .name = "discovery", - .tx = dhcp_discovery_tx, - .rx = dhcp_discovery_rx, - .expired = dhcp_discovery_expired, - .tx_msgtype = DHCPDISCOVER, - .apply_min_timeout = 1, -}; - -/** - * Construct transmitted packet for DHCP request - * - * @v dhcp DHCP session - * @v dhcppkt DHCP packet - * @v peer Destination address - */ -static int dhcp_request_tx ( struct dhcp_session *dhcp, - struct dhcp_packet *dhcppkt, - struct sockaddr_in *peer ) { - int rc; - struct dhcp_offer *offer; - - offer = dhcp->current_offer = dhcp_next_offer ( dhcp, DHCP_OFFER_IP ); - - DBGC ( dhcp, "DHCP %p DHCPREQUEST to %s:%d", - dhcp, inet_ntoa ( offer->server ), BOOTPS_PORT ); - DBGC ( dhcp, " for %s\n", inet_ntoa ( offer->ip ) ); - - /* Set server ID */ - if ( ( rc = dhcppkt_store ( dhcppkt, DHCP_SERVER_IDENTIFIER, - &offer->server, - sizeof ( offer->server ) ) ) != 0 ) - return rc; - - /* Set requested IP address */ - if ( ( rc = dhcppkt_store ( dhcppkt, DHCP_REQUESTED_ADDRESS, - &offer->ip, sizeof ( offer->ip ) ) ) != 0 ) - return rc; - - /* Set server address */ - peer->sin_addr.s_addr = INADDR_BROADCAST; - peer->sin_port = htons ( BOOTPS_PORT ); - - return 0; -} - -/** - * Handle received packet during DHCP request - * - * @v dhcp DHCP session - * @v dhcppkt DHCP packet - * @v peer DHCP server address - * @v msgtype DHCP message type - * @v server_id DHCP server ID - */ -static void dhcp_request_rx ( struct dhcp_session *dhcp, - struct dhcp_packet *dhcppkt, - struct sockaddr_in *peer, uint8_t msgtype, - struct in_addr server_id ) { - struct in_addr ip; - struct settings *parent; - int rc; - struct dhcp_offer *pxe_offer; - - if ( msgtype == DHCPOFFER ) { - dhcp_rx_offer ( dhcp, dhcppkt, peer, msgtype, server_id ); - if ( dhcp_next_offer ( dhcp, DHCP_OFFER_IP ) != - dhcp->current_offer ) { - /* Restart due to higher-priority offer received */ - DBGC ( dhcp, "DHCP %p re-requesting\n", dhcp ); - dhcp_set_state ( dhcp, &dhcp_state_request ); - } - return; - } - - DBGC ( dhcp, "DHCP %p %s from %s:%d", dhcp, - dhcp_msgtype_name ( msgtype ), inet_ntoa ( peer->sin_addr ), - ntohs ( peer->sin_port ) ); - if ( server_id.s_addr != peer->sin_addr.s_addr ) - DBGC ( dhcp, " (%s)", inet_ntoa ( server_id ) ); - - /* Identify leased IP address */ - ip = dhcppkt->dhcphdr->yiaddr; - if ( ip.s_addr ) - DBGC ( dhcp, " for %s", inet_ntoa ( ip ) ); - DBGC ( dhcp, "\n" ); - - /* Filter out unacceptable responses */ - if ( peer->sin_port != htons ( BOOTPS_PORT ) ) - return; - if ( msgtype /* BOOTP */ && ( msgtype != DHCPACK ) ) - return; - if ( server_id.s_addr != dhcp->current_offer->server.s_addr ) - return; - - /* Record assigned address */ - dhcp->local.sin_addr = ip; - - /* Register settings */ - parent = netdev_settings ( dhcp->netdev ); - if ( ( rc = register_settings ( &dhcppkt->settings, parent ) ) != 0 ){ - DBGC ( dhcp, "DHCP %p could not register settings: %s\n", - dhcp, strerror ( rc ) ); - dhcp_finished ( dhcp, rc ); - return; - } - - /* Locate best source of PXE settings */ - pxe_offer = dhcp_next_offer ( dhcp, DHCP_OFFER_PXE ); - - if ( ( ! pxe_offer ) || /* No PXE available */ - /* IP offer instructs us to ignore PXE */ - dhcp->current_offer->no_pxedhcp || - /* PXE settings already registered with IP offer */ - ( ( dhcp->current_offer == pxe_offer ) && ( pxe_offer->pxe ) ) ) { - - /* Terminate DHCP */ - dhcp_finished ( dhcp, 0 ); - - } else if ( pxe_offer->pxe ) { - /* Register PXE settings and terminate DHCP */ - pxe_offer->pxe->settings.name = PROXYDHCP_SETTINGS_NAME; - if ( ( rc = register_settings ( &pxe_offer->pxe->settings, - NULL ) ) != 0 ) { - DBGC ( dhcp, "DHCP %p could not register settings: " - "%s\n", dhcp, strerror ( rc ) ); - } - dhcp_finished ( dhcp, rc ); - } else { - /* Start ProxyDHCP */ - dhcp_set_state ( dhcp, &dhcp_state_proxy ); - } -} - -/** - * Handle timer expiry during DHCP discovery - * - * @v dhcp DHCP session - */ -static void dhcp_request_expired ( struct dhcp_session *dhcp ) { - - /* Retransmit current packet */ - dhcp_tx ( dhcp ); -} - -/** DHCP request state operations */ -static struct dhcp_session_state dhcp_state_request = { - .name = "request", - .tx = dhcp_request_tx, - .rx = dhcp_request_rx, - .expired = dhcp_request_expired, - .tx_msgtype = DHCPREQUEST, - .apply_min_timeout = 0, -}; - -/** - * Construct transmitted packet for ProxyDHCP request - * - * @v dhcp DHCP session - * @v dhcppkt DHCP packet - * @v peer Destination address - */ -static int dhcp_proxy_tx ( struct dhcp_session *dhcp, - struct dhcp_packet *dhcppkt, - struct sockaddr_in *peer ) { - int rc; - struct dhcp_offer *offer; - - offer = dhcp->current_offer = dhcp_next_offer ( dhcp, DHCP_OFFER_PXE ); - - DBGC ( dhcp, "DHCP %p ProxyDHCP REQUEST to %s:%d\n", dhcp, - inet_ntoa ( offer->server ), PXE_PORT ); - - /* Set server ID */ - if ( ( rc = dhcppkt_store ( dhcppkt, DHCP_SERVER_IDENTIFIER, - &offer->server, - sizeof ( offer->server ) ) ) != 0 ) - return rc; - - /* Set server address */ - peer->sin_addr = offer->server; - peer->sin_port = htons ( PXE_PORT ); - - return 0; -} - -/** - * Handle received packet during ProxyDHCP request - * - * @v dhcp DHCP session - * @v dhcppkt DHCP packet - * @v peer DHCP server address - * @v msgtype DHCP message type - * @v server_id DHCP server ID - */ -static void dhcp_proxy_rx ( struct dhcp_session *dhcp, - struct dhcp_packet *dhcppkt, - struct sockaddr_in *peer, uint8_t msgtype, - struct in_addr server_id ) { - int rc; - - /* Enqueue last-minute DHCPOFFERs for use in case of failure */ - if ( peer->sin_port == htons ( BOOTPS_PORT ) && - msgtype == DHCPOFFER ) { - dhcp_rx_offer ( dhcp, dhcppkt, peer, msgtype, server_id ); - return; - } - - DBGC ( dhcp, "DHCP %p %s from %s:%d", dhcp, - dhcp_msgtype_name ( msgtype ), inet_ntoa ( peer->sin_addr ), - ntohs ( peer->sin_port ) ); - if ( server_id.s_addr != peer->sin_addr.s_addr ) - DBGC ( dhcp, " (%s)", inet_ntoa ( server_id ) ); - DBGC ( dhcp, "\n" ); - - /* Filter out unacceptable responses */ - if ( peer->sin_port != htons ( PXE_PORT ) ) - return; - if ( msgtype != DHCPACK && msgtype != DHCPOFFER ) - return; - if ( server_id.s_addr /* Linux PXE server omits server ID */ && - ( server_id.s_addr != dhcp->current_offer->server.s_addr ) ) - return; - - /* Register settings */ - dhcppkt->settings.name = PROXYDHCP_SETTINGS_NAME; - if ( ( rc = register_settings ( &dhcppkt->settings, NULL ) ) != 0 ) { - DBGC ( dhcp, "DHCP %p could not register settings: %s\n", - dhcp, strerror ( rc ) ); - dhcp_finished ( dhcp, rc ); - return; - } - - /* Terminate DHCP */ - dhcp_finished ( dhcp, 0 ); -} - -/** - * Handle timer expiry during ProxyDHCP request - * - * @v dhcp DHCP session - */ -static void dhcp_proxy_expired ( struct dhcp_session *dhcp ) { - unsigned long elapsed = ( currticks() - dhcp->start ); - - /* Give up waiting for ProxyDHCP before we reach the failure point */ - if ( elapsed > PROXYDHCP_MAX_TIMEOUT ) { - - /* Mark failed offer as unsuitable for ProxyDHCP */ - dhcp->current_offer->valid &= ~DHCP_OFFER_PXE; - - /* Prefer not to use only half of a PXE+IP offer if we - * have other offers available - */ - dhcp->current_offer->priority = -1; - - /* If we have any other PXE offers we can try, go back - * to DHCPREQUEST (since they might not be proxied - * offers, or might be coupled to a new IP address). - * We should probably DHCPRELEASE our old IP, but the - * standard does not require it. - */ - if ( dhcp_next_offer ( dhcp, DHCP_OFFER_PXE ) ) { - dhcp->local.sin_addr.s_addr = 0; - dhcp_set_state ( dhcp, &dhcp_state_request ); - return; - } - - /* No possibilities left; finish without PXE options */ - dhcp_finished ( dhcp, 0 ); - return; - } - - /* Retransmit current packet */ - dhcp_tx ( dhcp ); -} - -/** ProxyDHCP request state operations */ -static struct dhcp_session_state dhcp_state_proxy = { - .name = "ProxyDHCP", - .tx = dhcp_proxy_tx, - .rx = dhcp_proxy_rx, - .expired = dhcp_proxy_expired, - .tx_msgtype = DHCPREQUEST, - .apply_min_timeout = 0, -}; - -/** - * Construct transmitted packet for PXE Boot Server Discovery - * - * @v dhcp DHCP session - * @v dhcppkt DHCP packet - * @v peer Destination address - */ -static int dhcp_pxebs_tx ( struct dhcp_session *dhcp, - struct dhcp_packet *dhcppkt, - struct sockaddr_in *peer ) { - struct dhcp_pxe_boot_menu_item menu_item = { 0, 0 }; - int rc; - - /* Set server address */ - peer->sin_addr = *(dhcp->pxe_attempt); - peer->sin_port = ( ( peer->sin_addr.s_addr == INADDR_BROADCAST ) ? - htons ( BOOTPS_PORT ) : htons ( PXE_PORT ) ); - - DBGC ( dhcp, "DHCP %p PXEBS REQUEST to %s:%d for type %d\n", - dhcp, inet_ntoa ( peer->sin_addr ), ntohs ( peer->sin_port ), - le16_to_cpu ( dhcp->pxe_type ) ); - - /* Set boot menu item */ - menu_item.type = dhcp->pxe_type; - if ( ( rc = dhcppkt_store ( dhcppkt, DHCP_PXE_BOOT_MENU_ITEM, - &menu_item, sizeof ( menu_item ) ) ) != 0 ) - return rc; - - return 0; -} - -/** - * Check to see if PXE Boot Server address is acceptable - * - * @v dhcp DHCP session - * @v bs Boot Server address - * @ret accept Boot Server is acceptable - */ -static int dhcp_pxebs_accept ( struct dhcp_session *dhcp, - struct in_addr bs ) { - struct in_addr *accept; - - /* Accept if we have no acceptance filter */ - if ( ! dhcp->pxe_accept ) - return 1; - - /* Scan through acceptance list */ - for ( accept = dhcp->pxe_accept ; accept->s_addr ; accept++ ) { - if ( accept->s_addr == bs.s_addr ) - return 1; - } - - DBGC ( dhcp, "DHCP %p rejecting server %s\n", - dhcp, inet_ntoa ( bs ) ); - return 0; -} - -/** - * Handle received packet during PXE Boot Server Discovery - * - * @v dhcp DHCP session - * @v dhcppkt DHCP packet - * @v peer DHCP server address - * @v msgtype DHCP message type - * @v server_id DHCP server ID - */ -static void dhcp_pxebs_rx ( struct dhcp_session *dhcp, - struct dhcp_packet *dhcppkt, - struct sockaddr_in *peer, uint8_t msgtype, - struct in_addr server_id ) { - struct dhcp_pxe_boot_menu_item menu_item = { 0, 0 }; - int rc; - - DBGC ( dhcp, "DHCP %p %s from %s:%d", dhcp, - dhcp_msgtype_name ( msgtype ), inet_ntoa ( peer->sin_addr ), - ntohs ( peer->sin_port ) ); - if ( server_id.s_addr != peer->sin_addr.s_addr ) - DBGC ( dhcp, " (%s)", inet_ntoa ( server_id ) ); - - /* Identify boot menu item */ - dhcppkt_fetch ( dhcppkt, DHCP_PXE_BOOT_MENU_ITEM, - &menu_item, sizeof ( menu_item ) ); - if ( menu_item.type ) - DBGC ( dhcp, " for type %d", ntohs ( menu_item.type ) ); - DBGC ( dhcp, "\n" ); - - /* Filter out unacceptable responses */ - if ( ( peer->sin_port != htons ( BOOTPS_PORT ) ) && - ( peer->sin_port != htons ( PXE_PORT ) ) ) - return; - if ( msgtype != DHCPACK ) - return; - if ( menu_item.type != dhcp->pxe_type ) - return; - if ( ! dhcp_pxebs_accept ( dhcp, ( server_id.s_addr ? - server_id : peer->sin_addr ) ) ) - return; - - /* Register settings */ - dhcppkt->settings.name = PXEBS_SETTINGS_NAME; - if ( ( rc = register_settings ( &dhcppkt->settings, NULL ) ) != 0 ) { - DBGC ( dhcp, "DHCP %p could not register settings: %s\n", - dhcp, strerror ( rc ) ); - dhcp_finished ( dhcp, rc ); - return; - } - - /* Terminate DHCP */ - dhcp_finished ( dhcp, 0 ); -} - -/** - * Handle timer expiry during PXE Boot Server Discovery - * - * @v dhcp DHCP session - */ -static void dhcp_pxebs_expired ( struct dhcp_session *dhcp ) { - unsigned long elapsed = ( currticks() - dhcp->start ); - - /* Give up waiting before we reach the failure point, and fail - * over to the next server in the attempt list - */ - if ( elapsed > PXEBS_MAX_TIMEOUT ) { - dhcp->pxe_attempt++; - if ( dhcp->pxe_attempt->s_addr ) { - dhcp_set_state ( dhcp, &dhcp_state_pxebs ); - return; - } else { - dhcp_finished ( dhcp, -ETIMEDOUT ); - return; - } - } - - /* Retransmit current packet */ - dhcp_tx ( dhcp ); -} - -/** PXE Boot Server Discovery state operations */ -static struct dhcp_session_state dhcp_state_pxebs = { - .name = "PXEBS", - .tx = dhcp_pxebs_tx, - .rx = dhcp_pxebs_rx, - .expired = dhcp_pxebs_expired, - .tx_msgtype = DHCPREQUEST, - .apply_min_timeout = 1, -}; - -/**************************************************************************** - * - * Packet construction - * - */ - -/** - * Construct DHCP client hardware address field and broadcast flag - * - * @v netdev Network device - * @v hlen DHCP hardware address length to fill in - * @v flags DHCP flags to fill in - * @ret chaddr DHCP client hardware address - */ -void * dhcp_chaddr ( struct net_device *netdev, uint8_t *hlen, - uint16_t *flags ) { - struct ll_protocol *ll_protocol = netdev->ll_protocol; - typeof ( ( ( struct dhcphdr * ) NULL )->chaddr ) chaddr; - - /* If the link-layer address cannot fit into the chaddr field - * (as is the case for IPoIB) then try using the hardware - * address instead. If we do this, set the broadcast flag, - * since chaddr then does not represent a valid link-layer - * address for the return path. - * - * If even the hardware address is too large, use an empty - * chaddr field and set the broadcast flag. - * - * This goes against RFC4390, but RFC4390 mandates that we use - * a DHCP client identifier that conforms with RFC4361, which - * we cannot do without either persistent (NIC-independent) - * storage, or by eliminating the hardware address completely - * from the DHCP packet, which seems unfriendly to users. - */ - if ( ( *hlen = ll_protocol->ll_addr_len ) <= sizeof ( chaddr ) ) { - return netdev->ll_addr; - } - *flags = htons ( BOOTP_FL_BROADCAST ); - if ( ( *hlen = ll_protocol->hw_addr_len ) <= sizeof ( chaddr ) ) { - return netdev->hw_addr; - } else { - *hlen = 0; - return NULL; - } -} - -/** - * Create a DHCP packet - * - * @v dhcppkt DHCP packet structure to fill in - * @v netdev Network device - * @v msgtype DHCP message type - * @v options Initial options to include (or NULL) - * @v options_len Length of initial options - * @v data Buffer for DHCP packet - * @v max_len Size of DHCP packet buffer - * @ret rc Return status code - * - * Creates a DHCP packet in the specified buffer, and initialise a - * DHCP packet structure. - */ -int dhcp_create_packet ( struct dhcp_packet *dhcppkt, - struct net_device *netdev, uint8_t msgtype, - const void *options, size_t options_len, - void *data, size_t max_len ) { - struct dhcphdr *dhcphdr = data; - void *chaddr; - int rc; - - /* Sanity check */ - if ( max_len < ( sizeof ( *dhcphdr ) + options_len ) ) - return -ENOSPC; - - /* Initialise DHCP packet content */ - memset ( dhcphdr, 0, max_len ); - dhcphdr->xid = dhcp_xid ( netdev ); - dhcphdr->magic = htonl ( DHCP_MAGIC_COOKIE ); - dhcphdr->htype = ntohs ( netdev->ll_protocol->ll_proto ); - dhcphdr->op = dhcp_op[msgtype]; - chaddr = dhcp_chaddr ( netdev, &dhcphdr->hlen, &dhcphdr->flags ); - memcpy ( dhcphdr->chaddr, chaddr, dhcphdr->hlen ); - memcpy ( dhcphdr->options, options, options_len ); - - /* Initialise DHCP packet structure */ - memset ( dhcppkt, 0, sizeof ( *dhcppkt ) ); - dhcppkt_init ( dhcppkt, data, max_len ); - - /* Set DHCP_MESSAGE_TYPE option */ - if ( ( rc = dhcppkt_store ( dhcppkt, DHCP_MESSAGE_TYPE, - &msgtype, sizeof ( msgtype ) ) ) != 0 ) - return rc; - - return 0; -} - -/** - * Create DHCP request packet - * - * @v dhcppkt DHCP packet structure to fill in - * @v netdev Network device - * @v msgtype DHCP message type - * @v ciaddr Client IP address - * @v data Buffer for DHCP packet - * @v max_len Size of DHCP packet buffer - * @ret rc Return status code - * - * Creates a DHCP request packet in the specified buffer, and - * initialise a DHCP packet structure. - */ -int dhcp_create_request ( struct dhcp_packet *dhcppkt, - struct net_device *netdev, unsigned int msgtype, - struct in_addr ciaddr, void *data, size_t max_len ) { - struct dhcp_netdev_desc dhcp_desc; - struct dhcp_client_id client_id; - struct dhcp_client_uuid client_uuid; - uint8_t *dhcp_features; - size_t dhcp_features_len; - size_t ll_addr_len; - ssize_t len; - int rc; - - /* Create DHCP packet */ - if ( ( rc = dhcp_create_packet ( dhcppkt, netdev, msgtype, - dhcp_request_options_data, - sizeof ( dhcp_request_options_data ), - data, max_len ) ) != 0 ) { - DBG ( "DHCP could not create DHCP packet: %s\n", - strerror ( rc ) ); - return rc; - } - - /* Set client IP address */ - dhcppkt->dhcphdr->ciaddr = ciaddr; - - /* Add options to identify the feature list */ - dhcp_features = table_start ( DHCP_FEATURES ); - dhcp_features_len = table_num_entries ( DHCP_FEATURES ); - if ( ( rc = dhcppkt_store ( dhcppkt, DHCP_EB_ENCAP, dhcp_features, - dhcp_features_len ) ) != 0 ) { - DBG ( "DHCP could not set features list option: %s\n", - strerror ( rc ) ); - return rc; - } - - /* Add options to identify the network device */ - fetch_setting ( &netdev->settings.settings, &busid_setting, &dhcp_desc, - sizeof ( dhcp_desc ) ); - if ( ( rc = dhcppkt_store ( dhcppkt, DHCP_EB_BUS_ID, &dhcp_desc, - sizeof ( dhcp_desc ) ) ) != 0 ) { - DBG ( "DHCP could not set bus ID option: %s\n", - strerror ( rc ) ); - return rc; - } - - /* Add DHCP client identifier. Required for Infiniband, and - * doesn't hurt other link layers. - */ - client_id.ll_proto = ntohs ( netdev->ll_protocol->ll_proto ); - ll_addr_len = netdev->ll_protocol->ll_addr_len; - assert ( ll_addr_len <= sizeof ( client_id.ll_addr ) ); - memcpy ( client_id.ll_addr, netdev->ll_addr, ll_addr_len ); - if ( ( rc = dhcppkt_store ( dhcppkt, DHCP_CLIENT_ID, &client_id, - ( ll_addr_len + 1 ) ) ) != 0 ) { - DBG ( "DHCP could not set client ID: %s\n", - strerror ( rc ) ); - return rc; - } - - /* Add client UUID, if we have one. Required for PXE. */ - client_uuid.type = DHCP_CLIENT_UUID_TYPE; - if ( ( len = fetch_uuid_setting ( NULL, &uuid_setting, - &client_uuid.uuid ) ) >= 0 ) { - if ( ( rc = dhcppkt_store ( dhcppkt, DHCP_CLIENT_UUID, - &client_uuid, - sizeof ( client_uuid ) ) ) != 0 ) { - DBG ( "DHCP could not set client UUID: %s\n", - strerror ( rc ) ); - return rc; - } - } - - /* Add user class, if we have one. */ - if ( ( len = fetch_setting_len ( NULL, &user_class_setting ) ) >= 0 ) { - char user_class[len]; - fetch_setting ( NULL, &user_class_setting, user_class, - sizeof ( user_class ) ); - if ( ( rc = dhcppkt_store ( dhcppkt, DHCP_USER_CLASS_ID, - &user_class, - sizeof ( user_class ) ) ) != 0 ) { - DBG ( "DHCP could not set user class: %s\n", - strerror ( rc ) ); - return rc; - } - } - - return 0; -} - -/**************************************************************************** - * - * Data transfer interface - * - */ - -/** - * Transmit DHCP request - * - * @v dhcp DHCP session - * @ret rc Return status code - */ -static int dhcp_tx ( struct dhcp_session *dhcp ) { - static struct sockaddr_in peer = { - .sin_family = AF_INET, - }; - struct xfer_metadata meta = { - .netdev = dhcp->netdev, - .src = ( struct sockaddr * ) &dhcp->local, - .dest = ( struct sockaddr * ) &peer, - }; - struct io_buffer *iobuf; - uint8_t msgtype = dhcp->state->tx_msgtype; - struct dhcp_packet dhcppkt; - int rc; - - /* Start retry timer. Do this first so that failures to - * transmit will be retried. - */ - start_timer ( &dhcp->timer ); - - /* Allocate buffer for packet */ - iobuf = xfer_alloc_iob ( &dhcp->xfer, DHCP_MIN_LEN ); - if ( ! iobuf ) - return -ENOMEM; - - /* Create basic DHCP packet in temporary buffer */ - if ( ( rc = dhcp_create_request ( &dhcppkt, dhcp->netdev, msgtype, - dhcp->local.sin_addr, iobuf->data, - iob_tailroom ( iobuf ) ) ) != 0 ) { - DBGC ( dhcp, "DHCP %p could not construct DHCP request: %s\n", - dhcp, strerror ( rc ) ); - goto done; - } - - /* Fill in packet based on current state */ - if ( ( rc = dhcp->state->tx ( dhcp, &dhcppkt, &peer ) ) != 0 ) { - DBGC ( dhcp, "DHCP %p could not fill DHCP request: %s\n", - dhcp, strerror ( rc ) ); - goto done; - } - - /* Transmit the packet */ - iob_put ( iobuf, dhcppkt.len ); - if ( ( rc = xfer_deliver_iob_meta ( &dhcp->xfer, iob_disown ( iobuf ), - &meta ) ) != 0 ) { - DBGC ( dhcp, "DHCP %p could not transmit UDP packet: %s\n", - dhcp, strerror ( rc ) ); - goto done; - } - - done: - free_iob ( iobuf ); - return rc; -} - -/** - * Receive new data - * - * @v xfer Data transfer interface - * @v iobuf I/O buffer - * @v meta Transfer metadata - * @ret rc Return status code - */ -static int dhcp_deliver_iob ( struct xfer_interface *xfer, - struct io_buffer *iobuf, - struct xfer_metadata *meta ) { - struct dhcp_session *dhcp = - container_of ( xfer, struct dhcp_session, xfer ); - struct sockaddr_in *peer; - size_t data_len; - struct dhcp_packet *dhcppkt; - struct dhcphdr *dhcphdr; - uint8_t msgtype = 0; - struct in_addr server_id = { 0 }; - int rc = 0; - - /* Sanity checks */ - if ( ! meta->src ) { - DBGC ( dhcp, "DHCP %p received packet without source port\n", - dhcp ); - rc = -EINVAL; - goto err_no_src; - } - peer = ( struct sockaddr_in * ) meta->src; - - /* Create a DHCP packet containing the I/O buffer contents. - * Whilst we could just use the original buffer in situ, that - * would waste the unused space in the packet buffer, and also - * waste a relatively scarce fully-aligned I/O buffer. - */ - data_len = iob_len ( iobuf ); - dhcppkt = zalloc ( sizeof ( *dhcppkt ) + data_len ); - if ( ! dhcppkt ) { - rc = -ENOMEM; - goto err_alloc_dhcppkt; - } - dhcphdr = ( ( ( void * ) dhcppkt ) + sizeof ( *dhcppkt ) ); - memcpy ( dhcphdr, iobuf->data, data_len ); - dhcppkt_init ( dhcppkt, dhcphdr, data_len ); - - /* Identify message type */ - dhcppkt_fetch ( dhcppkt, DHCP_MESSAGE_TYPE, &msgtype, - sizeof ( msgtype ) ); - - /* Identify server ID */ - dhcppkt_fetch ( dhcppkt, DHCP_SERVER_IDENTIFIER, - &server_id, sizeof ( server_id ) ); - - /* Check for matching transaction ID */ - if ( dhcphdr->xid != dhcp_xid ( dhcp->netdev ) ) { - DBGC ( dhcp, "DHCP %p %s from %s:%d has bad transaction " - "ID\n", dhcp, dhcp_msgtype_name ( msgtype ), - inet_ntoa ( peer->sin_addr ), - ntohs ( peer->sin_port ) ); - rc = -EINVAL; - goto err_xid; - }; - - /* Handle packet based on current state */ - dhcp->state->rx ( dhcp, dhcppkt, peer, msgtype, server_id ); - - err_xid: - dhcppkt_put ( dhcppkt ); - err_alloc_dhcppkt: - err_no_src: - free_iob ( iobuf ); - return rc; -} - -/** DHCP data transfer interface operations */ -static struct xfer_interface_operations dhcp_xfer_operations = { - .close = ignore_xfer_close, - .vredirect = xfer_vreopen, - .window = unlimited_xfer_window, - .alloc_iob = default_xfer_alloc_iob, - .deliver_iob = dhcp_deliver_iob, - .deliver_raw = xfer_deliver_as_iob, -}; - -/** - * Handle DHCP retry timer expiry - * - * @v timer DHCP retry timer - * @v fail Failure indicator - */ -static void dhcp_timer_expired ( struct retry_timer *timer, int fail ) { - struct dhcp_session *dhcp = - container_of ( timer, struct dhcp_session, timer ); - - /* If we have failed, terminate DHCP */ - if ( fail ) { - dhcp_finished ( dhcp, -ETIMEDOUT ); - return; - } - - /* Handle timer expiry based on current state */ - dhcp->state->expired ( dhcp ); -} - -/**************************************************************************** - * - * Job control interface - * - */ - -/** - * Handle kill() event received via job control interface - * - * @v job DHCP job control interface - */ -static void dhcp_job_kill ( struct job_interface *job ) { - struct dhcp_session *dhcp = - container_of ( job, struct dhcp_session, job ); - - /* Terminate DHCP session */ - dhcp_finished ( dhcp, -ECANCELED ); -} - -/** DHCP job control interface operations */ -static struct job_interface_operations dhcp_job_operations = { - .done = ignore_job_done, - .kill = dhcp_job_kill, - .progress = ignore_job_progress, -}; - -/**************************************************************************** - * - * Instantiators - * - */ - -/** - * DHCP peer address for socket opening - * - * This is a dummy address; the only useful portion is the socket - * family (so that we get a UDP connection). The DHCP client will set - * the IP address and source port explicitly on each transmission. - */ -static struct sockaddr dhcp_peer = { - .sa_family = AF_INET, -}; - -/** - * Start DHCP state machine on a network device - * - * @v job Job control interface - * @v netdev Network device - * @ret rc Return status code, or positive if cached - * - * Starts DHCP on the specified network device. If successful, the - * DHCPACK (and ProxyDHCPACK, if applicable) will be registered as - * option sources. - * - * On a return of 0, a background job has been started to perform the - * DHCP request. Any nonzero return means the job has not been - * started; a positive return value indicates the success condition of - * having fetched the appropriate data from cached information. - */ -int start_dhcp ( struct job_interface *job, struct net_device *netdev ) { - struct dhcp_session *dhcp; - int rc; - - /* Check for cached DHCP information */ - get_cached_dhcpack(); - if ( fetch_uintz_setting ( NULL, &use_cached_setting ) ) { - DBG ( "DHCP using cached network settings\n" ); - return 1; - } - - /* Allocate and initialise structure */ - dhcp = zalloc ( sizeof ( *dhcp ) ); - if ( ! dhcp ) - return -ENOMEM; - dhcp->refcnt.free = dhcp_free; - job_init ( &dhcp->job, &dhcp_job_operations, &dhcp->refcnt ); - xfer_init ( &dhcp->xfer, &dhcp_xfer_operations, &dhcp->refcnt ); - dhcp->netdev = netdev_get ( netdev ); - dhcp->local.sin_family = AF_INET; - dhcp->local.sin_port = htons ( BOOTPC_PORT ); - dhcp->timer.expired = dhcp_timer_expired; - - /* Instantiate child objects and attach to our interfaces */ - if ( ( rc = xfer_open_socket ( &dhcp->xfer, SOCK_DGRAM, &dhcp_peer, - ( struct sockaddr * ) &dhcp->local ) ) != 0 ) - goto err; - - /* Enter DHCPDISCOVER state */ - dhcp_set_state ( dhcp, &dhcp_state_discover ); - - /* Attach parent interface, mortalise self, and return */ - job_plug_plug ( &dhcp->job, job ); - ref_put ( &dhcp->refcnt ); - return 0; - - err: - dhcp_finished ( dhcp, rc ); - ref_put ( &dhcp->refcnt ); - return rc; -} - -/** - * Retrieve list of PXE boot servers for a given server type - * - * @v dhcp DHCP session - * @v raw DHCP PXE boot server list - * @v raw_len Length of DHCP PXE boot server list - * @v ip IP address list to fill in - * - * The caller must ensure that the IP address list has sufficient - * space. - */ -static void pxebs_list ( struct dhcp_session *dhcp, void *raw, - size_t raw_len, struct in_addr *ip ) { - struct dhcp_pxe_boot_server *server = raw; - size_t server_len; - unsigned int i; - - while ( raw_len ) { - if ( raw_len < sizeof ( *server ) ) { - DBGC ( dhcp, "DHCP %p malformed PXE server list\n", - dhcp ); - break; - } - server_len = offsetof ( typeof ( *server ), - ip[ server->num_ip ] ); - if ( raw_len < server_len ) { - DBGC ( dhcp, "DHCP %p malformed PXE server list\n", - dhcp ); - break; - } - if ( server->type == dhcp->pxe_type ) { - for ( i = 0 ; i < server->num_ip ; i++ ) - *(ip++) = server->ip[i]; - } - server = ( ( ( void * ) server ) + server_len ); - raw_len -= server_len; - } -} - -/** - * Start PXE Boot Server Discovery on a network device - * - * @v job Job control interface - * @v netdev Network device - * @v pxe_type PXE server type - * @ret rc Return status code - * - * Starts PXE Boot Server Discovery on the specified network device. - * If successful, the Boot Server ACK will be registered as an option - * source. - */ -int start_pxebs ( struct job_interface *job, struct net_device *netdev, - unsigned int pxe_type ) { - struct setting pxe_discovery_control_setting = - { .tag = DHCP_PXE_DISCOVERY_CONTROL }; - struct setting pxe_boot_servers_setting = - { .tag = DHCP_PXE_BOOT_SERVERS }; - struct setting pxe_boot_server_mcast_setting = - { .tag = DHCP_PXE_BOOT_SERVER_MCAST }; - ssize_t pxebs_list_len; - struct dhcp_session *dhcp; - struct in_addr *ip; - unsigned int pxe_discovery_control; - int rc; - - /* Get upper bound for PXE boot server IP address list */ - pxebs_list_len = fetch_setting_len ( NULL, &pxe_boot_servers_setting ); - if ( pxebs_list_len < 0 ) - pxebs_list_len = 0; - - /* Allocate and initialise structure */ - dhcp = zalloc ( sizeof ( *dhcp ) + sizeof ( *ip ) /* mcast */ + - sizeof ( *ip ) /* bcast */ + pxebs_list_len + - sizeof ( *ip ) /* terminator */ ); - if ( ! dhcp ) - return -ENOMEM; - dhcp->refcnt.free = dhcp_free; - job_init ( &dhcp->job, &dhcp_job_operations, &dhcp->refcnt ); - xfer_init ( &dhcp->xfer, &dhcp_xfer_operations, &dhcp->refcnt ); - dhcp->netdev = netdev_get ( netdev ); - dhcp->local.sin_family = AF_INET; - fetch_ipv4_setting ( netdev_settings ( netdev ), &ip_setting, - &dhcp->local.sin_addr ); - dhcp->local.sin_port = htons ( BOOTPC_PORT ); - dhcp->pxe_type = cpu_to_le16 ( pxe_type ); - dhcp->timer.expired = dhcp_timer_expired; - - /* Construct PXE boot server IP address lists */ - pxe_discovery_control = - fetch_uintz_setting ( NULL, &pxe_discovery_control_setting ); - ip = ( ( ( void * ) dhcp ) + sizeof ( *dhcp ) ); - dhcp->pxe_attempt = ip; - if ( ! ( pxe_discovery_control & PXEBS_NO_MULTICAST ) ) { - fetch_ipv4_setting ( NULL, &pxe_boot_server_mcast_setting, ip); - if ( ip->s_addr ) - ip++; - } - if ( ! ( pxe_discovery_control & PXEBS_NO_BROADCAST ) ) - (ip++)->s_addr = INADDR_BROADCAST; - if ( pxe_discovery_control & PXEBS_NO_UNKNOWN_SERVERS ) - dhcp->pxe_accept = ip; - if ( pxebs_list_len ) { - uint8_t buf[pxebs_list_len]; - - fetch_setting ( NULL, &pxe_boot_servers_setting, - buf, sizeof ( buf ) ); - pxebs_list ( dhcp, buf, sizeof ( buf ), ip ); - } - if ( ! dhcp->pxe_attempt->s_addr ) { - DBGC ( dhcp, "DHCP %p has no PXE boot servers for type %04x\n", - dhcp, pxe_type ); - rc = -EINVAL; - goto err; - } - - /* Dump out PXE server lists */ - DBGC ( dhcp, "DHCP %p attempting", dhcp ); - for ( ip = dhcp->pxe_attempt ; ip->s_addr ; ip++ ) - DBGC ( dhcp, " %s", inet_ntoa ( *ip ) ); - DBGC ( dhcp, "\n" ); - if ( dhcp->pxe_accept ) { - DBGC ( dhcp, "DHCP %p accepting", dhcp ); - for ( ip = dhcp->pxe_accept ; ip->s_addr ; ip++ ) - DBGC ( dhcp, " %s", inet_ntoa ( *ip ) ); - DBGC ( dhcp, "\n" ); - } - - /* Instantiate child objects and attach to our interfaces */ - if ( ( rc = xfer_open_socket ( &dhcp->xfer, SOCK_DGRAM, &dhcp_peer, - ( struct sockaddr * ) &dhcp->local ) ) != 0 ) - goto err; - - /* Enter PXEBS state */ - dhcp_set_state ( dhcp, &dhcp_state_pxebs ); - - /* Attach parent interface, mortalise self, and return */ - job_plug_plug ( &dhcp->job, job ); - ref_put ( &dhcp->refcnt ); - return 0; - - err: - dhcp_finished ( dhcp, rc ); - ref_put ( &dhcp->refcnt ); - return rc; -} |