dhcp.c File Reference

Dynamic Host Configuration Protocol. More...

#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
#include <errno.h>
#include <assert.h>
#include <byteswap.h>
#include <ipxe/if_ether.h>
#include <ipxe/iobuf.h>
#include <ipxe/netdevice.h>
#include <ipxe/device.h>
#include <ipxe/xfer.h>
#include <ipxe/open.h>
#include <ipxe/job.h>
#include <ipxe/retry.h>
#include <ipxe/tcpip.h>
#include <ipxe/ip.h>
#include <ipxe/uuid.h>
#include <ipxe/timer.h>
#include <ipxe/settings.h>
#include <ipxe/dhcp.h>
#include <ipxe/dhcpopts.h>
#include <ipxe/dhcppkt.h>
#include <ipxe/dhcparch.h>
#include <ipxe/features.h>
#include <config/dhcp.h>

Go to the source code of this file.

Data Structures
struct	dhcp_session_state
	DHCP session state operations. More...
struct	dhcp_session
	A DHCP session. More...

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
static int	dhcp_tx (struct dhcp_session *dhcp)
	Transmit DHCP request. More...
const struct setting dhcp_server_setting	__setting (SETTING_MISC, dhcp-server)
	DHCP server address setting. More...
static const char *	dhcp_msgtype_name (unsigned int msgtype)
	Name a DHCP packet type. More...
static void	dhcp_free (struct refcnt *refcnt)
	Free DHCP session. More...
static void	dhcp_finished (struct dhcp_session *dhcp, int rc)
	Mark DHCP session as complete. More...
static void	dhcp_set_state (struct dhcp_session *dhcp, struct dhcp_session_state *state)
	Transition to new DHCP session state. More...
static int	dhcp_has_pxeopts (struct dhcp_packet *dhcppkt)
	Check if DHCP packet contains PXE options. More...
static int	dhcp_discovery_tx (struct dhcp_session *dhcp, struct dhcp_packet *dhcppkt __unused, struct sockaddr_in *peer)
	Construct transmitted packet for DHCP discovery. More...
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, struct in_addr pseudo_id)
	Handle received packet during DHCP discovery. More...
static void	dhcp_defer (struct dhcp_session *dhcp)
	Defer DHCP discovery. More...
static void	dhcp_discovery_expired (struct dhcp_session *dhcp)
	Handle timer expiry during DHCP discovery. More...
static int	dhcp_request_tx (struct dhcp_session *dhcp, struct dhcp_packet *dhcppkt, struct sockaddr_in *peer)
	Construct transmitted packet for DHCP request. More...
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 pseudo_id)
	Handle received packet during DHCP request. More...
static void	dhcp_request_expired (struct dhcp_session *dhcp)
	Handle timer expiry during DHCP discovery. More...
static int	dhcp_proxy_tx (struct dhcp_session *dhcp, struct dhcp_packet *dhcppkt, struct sockaddr_in *peer)
	Construct transmitted packet for ProxyDHCP request. More...
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, struct in_addr pseudo_id)
	Handle received packet during ProxyDHCP request. More...
static void	dhcp_proxy_expired (struct dhcp_session *dhcp)
	Handle timer expiry during ProxyDHCP request. More...
static int	dhcp_pxebs_tx (struct dhcp_session *dhcp, struct dhcp_packet *dhcppkt, struct sockaddr_in *peer)
	Construct transmitted packet for PXE Boot Server Discovery. More...
static int	dhcp_pxebs_accept (struct dhcp_session *dhcp, struct in_addr bs)
	Check to see if PXE Boot Server address is acceptable. More...
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 in_addr pseudo_id)
	Handle received packet during PXE Boot Server Discovery. More...
static void	dhcp_pxebs_expired (struct dhcp_session *dhcp)
	Handle timer expiry during PXE Boot Server Discovery. More...
int	dhcp_create_packet (struct dhcp_packet *dhcppkt, struct net_device *netdev, uint8_t msgtype, uint32_t xid, const void *options, size_t options_len, void *data, size_t max_len)
	Create a DHCP packet. More...
int	dhcp_create_request (struct dhcp_packet *dhcppkt, struct net_device *netdev, unsigned int msgtype, uint32_t xid, struct in_addr ciaddr, void *data, size_t max_len)
	Create DHCP request packet. More...
static int	dhcp_deliver (struct dhcp_session *dhcp, struct io_buffer *iobuf, struct xfer_metadata *meta)
	Receive new data. More...
static void	dhcp_timer_expired (struct retry_timer *timer, int fail)
	Handle DHCP retry timer expiry. More...
int	start_dhcp (struct interface *job, struct net_device *netdev)
	Start DHCP state machine on a network device. More...
static void	pxebs_list (struct dhcp_session *dhcp, void *raw, size_t raw_len, struct in_addr *ip)
	Retrieve list of PXE boot servers for a given server type. More...
int	start_pxebs (struct interface *job, struct net_device *netdev, unsigned int pxe_type)
	Start PXE Boot Server Discovery on a network device. More...

Variables
static const uint8_t	dhcp_op []
	DHCP operation types. More...
static uint8_t	dhcp_request_options_data []
	Raw option data for options common to all DHCP requests. More...
static const struct setting *	dhcp_request_settings []
	Settings copied in to all DHCP requests. More...
uint32_t	dhcp_last_xid
	Most recent DHCP transaction ID. More...
static struct dhcp_session_state	dhcp_state_discover
	DHCP discovery state operations. More...
static struct dhcp_session_state	dhcp_state_request
	DHCP request state operations. More...
static struct dhcp_session_state	dhcp_state_proxy
	ProxyDHCP request state operations. More...
static struct dhcp_session_state	dhcp_state_pxebs
	PXE Boot Server Discovery state operations. More...
static struct interface_operation	dhcp_xfer_operations []
	DHCP data transfer interface operations. More...
static struct interface_descriptor	dhcp_xfer_desc
	DHCP data transfer interface descriptor. More...
static struct interface_operation	dhcp_job_op []
	DHCP job control interface operations. More...
static struct interface_descriptor	dhcp_job_desc
	DHCP job control interface descriptor. More...
static struct sockaddr	dhcp_peer
	DHCP peer address for socket opening. More...
struct net_device_configurator dhcp_configurator	__net_device_configurator
	DHCP network device configurator. More...

Detailed Description

Dynamic Host Configuration Protocol.

Definition in file dhcp.c.

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

dhcp_tx()

static int dhcp_tx ( struct dhcp_session *  dhcp )

static

Transmit DHCP request.

Parameters

dhcp	DHCP session

Return values

rc	Return status code

Definition at line 1125 of file dhcp.c.

                                                 {
        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->xid, 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;
        }

        /* (Ab)use the "secs" field to convey metadata about the DHCP
         * session state into packet traces.  Useful for extracting
         * debug information from non-debug builds.
         */
        dhcppkt.dhcphdr->secs = htons ( ( dhcp->count << 2 ) |
                                        ( dhcp->offer.s_addr ? 0x02 : 0 ) |
                                        ( dhcp->proxy_offer ? 0x01 : 0 ) );

        /* 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 ( &dhcppkt ) );
        if ( ( rc = xfer_deliver ( &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;
}

References AF_INET, dhcp_session::count, io_buffer::data, DBGC, dhcp_create_request(), DHCP_MIN_LEN, dhcp_packet::dhcphdr, dhcppkt_len(), done, ENOMEM, free_iob(), htons, iob_disown, iob_put, iob_tailroom(), dhcp_session::local, meta(), dhcp_session::netdev, dhcp_session::offer, peer, dhcp_session::proxy_offer, rc, in_addr::s_addr, dhcphdr::secs, sockaddr_in::sin_addr, start_timer(), dhcp_session::state, strerror(), dhcp_session::timer, dhcp_session_state::tx, dhcp_session_state::tx_msgtype, dhcp_session::xfer, xfer_alloc_iob(), xfer_deliver(), and dhcp_session::xid.

Referenced by dhcp_discovery_expired(), dhcp_proxy_expired(), dhcp_pxebs_expired(), and dhcp_request_expired().

__setting()

const struct setting dhcp_server_setting __setting	(	SETTING_MISC	,
		dhcp-	server
	)

DHCP server address setting.

dhcp_msgtype_name()

static const char* dhcp_msgtype_name ( unsigned int  msgtype )

inlinestatic

Name a DHCP packet type.

Parameters

msgtype

DHCP message type

Return values

string

DHCP mesasge type name

Definition at line 132 of file dhcp.c.

                                                                      {
        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>";
        }
}

References DHCPACK, DHCPDECLINE, DHCPDISCOVER, DHCPINFORM, DHCPNAK, DHCPNONE, DHCPOFFER, DHCPRELEASE, and DHCPREQUEST.

Referenced by dhcp_deliver(), dhcp_discovery_rx(), dhcp_proxy_rx(), dhcp_pxebs_rx(), and dhcp_request_rx().

dhcp_free()

static void dhcp_free ( struct refcnt *  refcnt )

static

Free DHCP session.

Parameters

refcnt

Reference counter

Definition at line 253 of file dhcp.c.

                                                {
        struct dhcp_session *dhcp =
                container_of ( refcnt, struct dhcp_session, refcnt );

        netdev_put ( dhcp->netdev );
        dhcppkt_put ( dhcp->proxy_offer );
        free ( dhcp );
}

References container_of, dhcppkt_put(), free, dhcp_session::netdev, netdev_put(), and dhcp_session::proxy_offer.

Referenced by start_dhcp(), and start_pxebs().

dhcp_finished()

static void dhcp_finished ( struct dhcp_session *  dhcp, int  rc  )

static

Mark DHCP session as complete.

Parameters

dhcp	DHCP session
rc	Return status code

Definition at line 268 of file dhcp.c.

                                                                {

        /* Stop retry timer */
        stop_timer ( &dhcp->timer );

        /* Shut down interfaces */
        intf_shutdown ( &dhcp->xfer, rc );
        intf_shutdown ( &dhcp->job, rc );
}

References intf_shutdown(), dhcp_session::job, rc, stop_timer(), dhcp_session::timer, and dhcp_session::xfer.

Referenced by dhcp_proxy_expired(), dhcp_proxy_rx(), dhcp_pxebs_expired(), dhcp_pxebs_rx(), dhcp_request_rx(), dhcp_timer_expired(), start_dhcp(), and start_pxebs().

dhcp_set_state()

static void dhcp_set_state ( struct dhcp_session *  dhcp, struct dhcp_session_state *  state  )

static

Transition to new DHCP session state.

Parameters

dhcp	DHCP session
state	New session state

Definition at line 284 of file dhcp.c.

                                                                {

        DBGC ( dhcp, "DHCP %p entering %s state\n", dhcp, state->name );
        dhcp->state = state;
        dhcp->start = currticks();
        stop_timer ( &dhcp->timer );
        set_timer_limits ( &dhcp->timer,
                           ( state->min_timeout_sec * TICKS_PER_SEC ),
                           ( state->max_timeout_sec * TICKS_PER_SEC ) );
        start_timer_nodelay ( &dhcp->timer );
}

References currticks(), DBGC, dhcp_session::start, start_timer_nodelay(), state, dhcp_session::state, stop_timer(), TICKS_PER_SEC, and dhcp_session::timer.

Referenced by dhcp_defer(), dhcp_discovery_expired(), dhcp_discovery_rx(), dhcp_pxebs_expired(), dhcp_request_rx(), start_dhcp(), and start_pxebs().

dhcp_has_pxeopts()

static int dhcp_has_pxeopts ( struct dhcp_packet *  dhcppkt )

static

Check if DHCP packet contains PXE options.

Parameters

dhcppkt

DHCP packet

Return values

has_pxeopts

DHCP packet contains PXE options

It is assumed that the packet is already known to contain option 60 set to "PXEClient".

Definition at line 306 of file dhcp.c.

                                                            {

        /* Check for a next-server and boot filename */
        if ( dhcppkt->dhcphdr->siaddr.s_addr &&
             ( dhcppkt_fetch ( dhcppkt, DHCP_BOOTFILE_NAME, NULL, 0 ) > 0 ) )
                return 1;

        /* Check for a PXE boot menu */
        if ( dhcppkt_fetch ( dhcppkt, DHCP_PXE_BOOT_MENU, NULL, 0 ) > 0 )
                return 1;

        return 0;
}

References DHCP_BOOTFILE_NAME, DHCP_PXE_BOOT_MENU, dhcp_packet::dhcphdr, dhcppkt_fetch(), NULL, in_addr::s_addr, and dhcphdr::siaddr.

Referenced by dhcp_discovery_rx(), dhcp_proxy_rx(), and dhcp_request_rx().

dhcp_discovery_tx()

static int dhcp_discovery_tx ( struct dhcp_session *  dhcp, struct dhcp_packet *dhcppkt  __unused, struct sockaddr_in *  peer  )

static

Construct transmitted packet for DHCP discovery.

Parameters

dhcp	DHCP session
dhcppkt	DHCP packet
peer	Destination address

Definition at line 333 of file dhcp.c.

                                                          {

        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;
}

References BOOTPS_PORT, DBGC, htons, INADDR_BROADCAST, and peer.

dhcp_discovery_rx()

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, struct in_addr  pseudo_id  )

static

Handle received packet during DHCP discovery.

Parameters

dhcp	DHCP session
dhcppkt	DHCP packet
peer	DHCP server address
msgtype	DHCP message type
server_id	DHCP server ID
pseudo_id	DHCP server pseudo-ID

Definition at line 356 of file dhcp.c.

                                                           {
        struct in_addr ip;
        char vci[9]; /* "PXEClient" */
        int vci_len;
        int has_pxeclient;
        int8_t priority = 0;
        uint8_t no_pxedhcp = 0;
        unsigned long elapsed;

        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 ) ||
             ( pseudo_id.s_addr != peer->sin_addr.s_addr ) ) {
                DBGC ( dhcp, " (%s/", inet_ntoa ( server_id ) );
                DBGC ( dhcp, "%s)", inet_ntoa ( pseudo_id ) );
        }

        /* Identify offered IP address */
        ip = dhcppkt->dhcphdr->yiaddr;
        if ( ip.s_addr )
                DBGC ( dhcp, " for %s", inet_ntoa ( ip ) );

        /* 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 ));
        if ( has_pxeclient ) {
                DBGC ( dhcp, "%s",
                       ( dhcp_has_pxeopts ( dhcppkt ) ? " pxe" : " proxy" ) );
        }

        /* Identify priority */
        dhcppkt_fetch ( dhcppkt, DHCP_EB_PRIORITY, &priority,
                        sizeof ( priority ) );
        if ( priority )
                DBGC ( dhcp, " pri %d", priority );

        /* Identify ignore-PXE flag */
        dhcppkt_fetch ( dhcppkt, DHCP_EB_NO_PXEDHCP, &no_pxedhcp,
                        sizeof ( no_pxedhcp ) );
        if ( no_pxedhcp )
                DBGC ( dhcp, " nopxe" );
        DBGC ( dhcp, "\n" );

        /* Select as DHCP offer, if applicable */
        if ( ip.s_addr && ( peer->sin_port == htons ( BOOTPS_PORT ) ) &&
             ( ( msgtype == DHCPOFFER ) || ( ! msgtype /* BOOTP */ ) ) &&
             ( priority >= dhcp->priority ) ) {
                dhcp->offer = ip;
                dhcp->server = server_id;
                dhcp->priority = priority;
                dhcp->no_pxedhcp = no_pxedhcp;
        }

        /* Select as ProxyDHCP offer, if applicable */
        if ( pseudo_id.s_addr && has_pxeclient &&
             ( priority >= dhcp->proxy_priority ) ) {
                dhcppkt_put ( dhcp->proxy_offer );
                dhcp->proxy_server = pseudo_id;
                dhcp->proxy_offer = dhcppkt_get ( dhcppkt );
                dhcp->proxy_priority = priority;
        }

        /* 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 */
        if ( ! dhcp->offer.s_addr )
                return;

        /* If we can't yet transition to DHCPREQUEST, do nothing */
        elapsed = ( currticks() - dhcp->start );
        if ( ! ( dhcp->no_pxedhcp || dhcp->proxy_offer ||
                 ( elapsed > DHCP_DISC_PROXY_TIMEOUT_SEC * TICKS_PER_SEC ) ) )
                return;

        /* Transition to DHCPREQUEST */
        dhcp_set_state ( dhcp, &dhcp_state_request );
}

References BOOTPS_PORT, currticks(), DBGC, DHCP_DISC_PROXY_TIMEOUT_SEC, DHCP_EB_NO_PXEDHCP, DHCP_EB_PRIORITY, dhcp_has_pxeopts(), dhcp_msgtype_name(), dhcp_set_state(), dhcp_state_request, DHCP_VENDOR_CLASS_ID, dhcp_packet::dhcphdr, DHCPOFFER, dhcppkt_fetch(), dhcppkt_get(), dhcppkt_put(), htons, inet_ntoa(), ip, dhcp_session::no_pxedhcp, ntohs, dhcp_session::offer, peer, priority, dhcp_session::priority, dhcp_session::proxy_offer, dhcp_session::proxy_priority, dhcp_session::proxy_server, in_addr::s_addr, dhcp_session::server, dhcp_session::start, strncmp(), TICKS_PER_SEC, and dhcphdr::yiaddr.

dhcp_defer()

static void dhcp_defer ( struct dhcp_session *  dhcp )

static

Defer DHCP discovery.

Parameters

dhcp	DHCP session

Definition at line 452 of file dhcp.c.

                                                     {

        /* Do nothing if we have reached the deferral limit */
        if ( dhcp->count > DHCP_DISC_MAX_DEFERRALS )
                return;

        /* Return to discovery state */
        DBGC ( dhcp, "DHCP %p deferring discovery\n", dhcp );
        dhcp_set_state ( dhcp, &dhcp_state_discover );

        /* Delay first DHCPDISCOVER */
        start_timer_fixed ( &dhcp->timer,
                            ( DHCP_DISC_START_TIMEOUT_SEC * TICKS_PER_SEC ) );
}

References dhcp_session::count, DBGC, DHCP_DISC_MAX_DEFERRALS, DHCP_DISC_START_TIMEOUT_SEC, dhcp_set_state(), dhcp_state_discover, start_timer_fixed(), TICKS_PER_SEC, and dhcp_session::timer.

Referenced by dhcp_discovery_expired(), and dhcp_request_rx().

dhcp_discovery_expired()

static void dhcp_discovery_expired ( struct dhcp_session *  dhcp )

static

Handle timer expiry during DHCP discovery.

Parameters

dhcp	DHCP session

Definition at line 472 of file dhcp.c.

                                                                 {
        unsigned long elapsed = ( currticks() - dhcp->start );

        /* Give up waiting for ProxyDHCP before we reach the failure point */
        if ( dhcp->offer.s_addr &&
             ( elapsed > DHCP_DISC_PROXY_TIMEOUT_SEC * TICKS_PER_SEC ) ) {
                dhcp_set_state ( dhcp, &dhcp_state_request );
                return;
        }

        /* Retransmit current packet */
        dhcp_tx ( dhcp );

        /* If link is blocked, defer DHCP discovery timeout */
        if ( netdev_link_blocked ( dhcp->netdev ) )
             dhcp_defer ( dhcp );
}

References currticks(), dhcp_defer(), DHCP_DISC_PROXY_TIMEOUT_SEC, dhcp_set_state(), dhcp_state_request, dhcp_tx(), dhcp_session::netdev, netdev_link_blocked(), dhcp_session::offer, in_addr::s_addr, dhcp_session::start, and TICKS_PER_SEC.

dhcp_request_tx()

static int dhcp_request_tx ( struct dhcp_session *  dhcp, struct dhcp_packet *  dhcppkt, struct sockaddr_in *  peer  )

static

Construct transmitted packet for DHCP request.

Parameters

dhcp	DHCP session
dhcppkt	DHCP packet
peer	Destination address

Definition at line 508 of file dhcp.c.

                                                        {
        int rc;

        DBGC ( dhcp, "DHCP %p DHCPREQUEST to %s:%d",
               dhcp, inet_ntoa ( dhcp->server ), BOOTPS_PORT );
        DBGC ( dhcp, " for %s\n", inet_ntoa ( dhcp->offer ) );

        /* Set server ID */
        if ( ( rc = dhcppkt_store ( dhcppkt, DHCP_SERVER_IDENTIFIER,
                                    &dhcp->server,
                                    sizeof ( dhcp->server ) ) ) != 0 )
                return rc;

        /* Set requested IP address */
        if ( ( rc = dhcppkt_store ( dhcppkt, DHCP_REQUESTED_ADDRESS,
                                    &dhcp->offer,
                                    sizeof ( dhcp->offer ) ) ) != 0 )
                return rc;

        /* Set server address */
        peer->sin_addr.s_addr = INADDR_BROADCAST;
        peer->sin_port = htons ( BOOTPS_PORT );

        return 0;
}

References BOOTPS_PORT, DBGC, DHCP_REQUESTED_ADDRESS, DHCP_SERVER_IDENTIFIER, dhcppkt_store(), htons, INADDR_BROADCAST, inet_ntoa(), dhcp_session::offer, peer, rc, and dhcp_session::server.

dhcp_request_rx()

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  pseudo_id  )

static

Handle received packet during DHCP request.

Parameters

dhcp	DHCP session
dhcppkt	DHCP packet
peer	DHCP server address
msgtype	DHCP message type
server_id	DHCP server ID
pseudo_id	DHCP server pseudo-ID

Definition at line 546 of file dhcp.c.

                                                         {
        struct in_addr ip;
        struct settings *parent;
        struct settings *settings;
        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 ) ||
             ( pseudo_id.s_addr != peer->sin_addr.s_addr ) ) {
                DBGC ( dhcp, " (%s/", inet_ntoa ( server_id ) );
                DBGC ( dhcp, "%s)", inet_ntoa ( pseudo_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 invalid port */
        if ( peer->sin_port != htons ( BOOTPS_PORT ) )
                return;

        /* Filter out non-selected servers */
        if ( server_id.s_addr != dhcp->server.s_addr )
                return;

        /* Handle DHCPNAK */
        if ( msgtype == DHCPNAK ) {
                dhcp_defer ( dhcp );
                return;
        }

        /* Filter out unacceptable responses */
        if ( msgtype /* BOOTP */ && ( msgtype != DHCPACK ) )
                return;
        if ( ip.s_addr != dhcp->offer.s_addr )
                return;

        /* Record assigned address */
        dhcp->local.sin_addr = ip;

        /* Register settings */
        parent = netdev_settings ( dhcp->netdev );
        settings = &dhcppkt->settings;
        if ( ( rc = register_settings ( settings, parent,
                                        DHCP_SETTINGS_NAME ) ) != 0 ) {
                DBGC ( dhcp, "DHCP %p could not register settings: %s\n",
                       dhcp, strerror ( rc ) );
                dhcp_finished ( dhcp, rc );
                return;
        }

        /* Unregister any existing ProxyDHCP or PXEBS settings */
        if ( ( settings = find_settings ( PROXYDHCP_SETTINGS_NAME ) ) != NULL )
                unregister_settings ( settings );
        if ( ( settings = find_settings ( PXEBS_SETTINGS_NAME ) ) != NULL )
                unregister_settings ( settings );

        /* Perform ProxyDHCP if applicable */
        if ( dhcp->proxy_offer /* Have ProxyDHCP offer */ &&
             ( ! dhcp->no_pxedhcp ) /* ProxyDHCP not disabled */ ) {
                if ( dhcp_has_pxeopts ( dhcp->proxy_offer ) ) {
                        /* PXE options already present; register settings
                         * without performing a ProxyDHCPREQUEST
                         */
                        settings = &dhcp->proxy_offer->settings;
                        if ( ( rc = register_settings ( settings, NULL,
                                           PROXYDHCP_SETTINGS_NAME ) ) != 0 ) {
                                DBGC ( dhcp, "DHCP %p could not register "
                                       "proxy settings: %s\n",
                                       dhcp, strerror ( rc ) );
                                dhcp_finished ( dhcp, rc );
                                return;
                        }
                } else {
                        /* PXE options not present; use a ProxyDHCPREQUEST */
                        dhcp_set_state ( dhcp, &dhcp_state_proxy );
                        return;
                }
        }

        /* Terminate DHCP */
        dhcp_finished ( dhcp, 0 );
}

References BOOTPS_PORT, DBGC, dhcp_defer(), dhcp_finished(), dhcp_has_pxeopts(), dhcp_msgtype_name(), dhcp_set_state(), DHCP_SETTINGS_NAME, dhcp_state_proxy, DHCPACK, dhcp_packet::dhcphdr, DHCPNAK, find_settings(), htons, inet_ntoa(), ip, dhcp_session::local, dhcp_session::netdev, netdev_settings(), dhcp_session::no_pxedhcp, ntohs, NULL, dhcp_session::offer, settings::parent, peer, dhcp_session::proxy_offer, PROXYDHCP_SETTINGS_NAME, PXEBS_SETTINGS_NAME, rc, register_settings(), in_addr::s_addr, dhcp_session::server, dhcp_packet::settings, sockaddr_in::sin_addr, strerror(), unregister_settings(), and dhcphdr::yiaddr.

dhcp_request_expired()

static void dhcp_request_expired ( struct dhcp_session *  dhcp )

static

Handle timer expiry during DHCP discovery.

Parameters

dhcp	DHCP session

Definition at line 643 of file dhcp.c.

                                                               {

        /* Retransmit current packet */
        dhcp_tx ( dhcp );
}

References dhcp_tx().

dhcp_proxy_tx()

static int dhcp_proxy_tx ( struct dhcp_session *  dhcp, struct dhcp_packet *  dhcppkt, struct sockaddr_in *  peer  )

static

Construct transmitted packet for ProxyDHCP request.

Parameters

dhcp	DHCP session
dhcppkt	DHCP packet
peer	Destination address

Definition at line 667 of file dhcp.c.

                                                      {
        int rc;

        DBGC ( dhcp, "DHCP %p ProxyDHCP REQUEST to %s\n", dhcp,
               inet_ntoa ( dhcp->proxy_server ) );

        /* Set server ID */
        if ( ( rc = dhcppkt_store ( dhcppkt, DHCP_SERVER_IDENTIFIER,
                                    &dhcp->proxy_server,
                                    sizeof ( dhcp->proxy_server ) ) ) != 0 )
                return rc;

        /* Set server address */
        peer->sin_addr = dhcp->proxy_server;
        peer->sin_port = htons ( PXE_PORT );

        return 0;
}

References DBGC, DHCP_SERVER_IDENTIFIER, dhcppkt_store(), htons, inet_ntoa(), peer, dhcp_session::proxy_server, PXE_PORT, and rc.

dhcp_proxy_rx()

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, struct in_addr  pseudo_id  )

static

Handle received packet during ProxyDHCP request.

Parameters

dhcp	DHCP session
dhcppkt	DHCP packet
peer	DHCP server address
msgtype	DHCP message type
server_id	DHCP server ID
pseudo_id	DHCP server pseudo-ID

Definition at line 698 of file dhcp.c.

                                                       {
        struct settings *settings = &dhcppkt->settings;
        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 ) ||
             ( pseudo_id.s_addr != peer->sin_addr.s_addr ) ) {
                DBGC ( dhcp, " (%s/", inet_ntoa ( server_id ) );
                DBGC ( dhcp, "%s)", inet_ntoa ( pseudo_id ) );
        }
        if ( dhcp_has_pxeopts ( dhcppkt ) )
                DBGC ( dhcp, " pxe" );
        DBGC ( dhcp, "\n" );

        /* Filter out unacceptable responses */
        if ( peer->sin_port != ntohs ( PXE_PORT ) )
                return;
        if ( ( msgtype != DHCPOFFER ) && ( msgtype != DHCPACK ) )
                return;
        if ( ( pseudo_id.s_addr != dhcp->proxy_server.s_addr ) )
                return;
        if ( ! dhcp_has_pxeopts ( dhcppkt ) )
                return;

        /* Register settings */
        if ( ( rc = register_settings ( settings, NULL,
                                        PROXYDHCP_SETTINGS_NAME ) ) != 0 ) {
                DBGC ( dhcp, "DHCP %p could not register proxy settings: %s\n",
                       dhcp, strerror ( rc ) );
                dhcp_finished ( dhcp, rc );
                return;
        }

        /* Terminate DHCP */
        dhcp_finished ( dhcp, 0 );
}

References DBGC, dhcp_finished(), dhcp_has_pxeopts(), dhcp_msgtype_name(), DHCPACK, DHCPOFFER, inet_ntoa(), ntohs, NULL, peer, dhcp_session::proxy_server, PROXYDHCP_SETTINGS_NAME, PXE_PORT, rc, register_settings(), in_addr::s_addr, dhcp_packet::settings, and strerror().

dhcp_proxy_expired()

static void dhcp_proxy_expired ( struct dhcp_session *  dhcp )

static

Handle timer expiry during ProxyDHCP request.

Parameters

dhcp	DHCP session

Definition at line 746 of file dhcp.c.

                                                             {
        unsigned long elapsed = ( currticks() - dhcp->start );

        /* Give up waiting for ProxyDHCP before we reach the failure point */
        if ( elapsed > DHCP_REQ_PROXY_TIMEOUT_SEC * TICKS_PER_SEC ) {
                dhcp_finished ( dhcp, 0 );
                return;
        }

        /* Retransmit current packet */
        dhcp_tx ( dhcp );
}

References currticks(), dhcp_finished(), DHCP_REQ_PROXY_TIMEOUT_SEC, dhcp_tx(), dhcp_session::start, and TICKS_PER_SEC.

dhcp_pxebs_tx()

static int dhcp_pxebs_tx ( struct dhcp_session *  dhcp, struct dhcp_packet *  dhcppkt, struct sockaddr_in *  peer  )

static

Construct transmitted packet for PXE Boot Server Discovery.

Parameters

dhcp	DHCP session
dhcppkt	DHCP packet
peer	Destination address

Definition at line 777 of file dhcp.c.

                                                      {
        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;
}

References BOOTPS_PORT, DBGC, DHCP_PXE_BOOT_MENU_ITEM, dhcppkt_store(), htons, INADDR_BROADCAST, inet_ntoa(), le16_to_cpu, ntohs, peer, dhcp_session::pxe_attempt, PXE_PORT, dhcp_session::pxe_type, and rc.

dhcp_pxebs_accept()

static int dhcp_pxebs_accept ( struct dhcp_session *  dhcp, struct in_addr  bs  )

static

Check to see if PXE Boot Server address is acceptable.

Parameters

dhcp	DHCP session
bs	Boot Server address

Return values

accept

Boot Server is acceptable

Definition at line 808 of file dhcp.c.

                                                   {
        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;
}

References DBGC, inet_ntoa(), dhcp_session::pxe_accept, and in_addr::s_addr.

Referenced by dhcp_pxebs_rx().

dhcp_pxebs_rx()

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 in_addr  pseudo_id  )

static

Handle received packet during PXE Boot Server Discovery.

Parameters

dhcp	DHCP session
dhcppkt	DHCP packet
peer	DHCP server address
msgtype	DHCP message type
server_id	DHCP server ID
pseudo_id	DHCP server pseudo-ID

Definition at line 837 of file dhcp.c.

                                                       {
        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 ) ||
             ( pseudo_id.s_addr != peer->sin_addr.s_addr ) ) {
                DBGC ( dhcp, " (%s/", inet_ntoa ( server_id ) );
                DBGC ( dhcp, "%s)", inet_ntoa ( pseudo_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, pseudo_id ) )
                return;

        /* Register settings */
        if ( ( rc = register_settings ( &dhcppkt->settings, NULL,
                                        PXEBS_SETTINGS_NAME ) ) != 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 );
}

References BOOTPS_PORT, DBGC, dhcp_finished(), dhcp_msgtype_name(), DHCP_PXE_BOOT_MENU_ITEM, dhcp_pxebs_accept(), DHCPACK, dhcppkt_fetch(), htons, inet_ntoa(), ntohs, NULL, peer, PXE_PORT, dhcp_session::pxe_type, PXEBS_SETTINGS_NAME, rc, register_settings(), in_addr::s_addr, dhcp_packet::settings, and strerror().

dhcp_pxebs_expired()

static void dhcp_pxebs_expired ( struct dhcp_session *  dhcp )

static

Handle timer expiry during PXE Boot Server Discovery.

Parameters

dhcp	DHCP session

Definition at line 890 of file dhcp.c.

                                                             {
        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_SEC * TICKS_PER_SEC ) {
                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 );
}

References currticks(), dhcp_finished(), dhcp_set_state(), dhcp_state_pxebs, dhcp_tx(), ETIMEDOUT, dhcp_session::pxe_attempt, PXEBS_MAX_TIMEOUT_SEC, in_addr::s_addr, dhcp_session::start, and TICKS_PER_SEC.

dhcp_create_packet()

int dhcp_create_packet	(	struct dhcp_packet *	dhcppkt,
		struct net_device *	netdev,
		uint8_t	msgtype,
		uint32_t	xid,
		const void *	options,
		size_t	options_len,
		void *	data,
		size_t	max_len
	)

Create a DHCP packet.

Parameters

dhcppkt	DHCP packet structure to fill in
netdev	Network device
msgtype	DHCP message type
xid	Transaction ID (in network-endian order)
options	Initial options to include (or NULL)
options_len	Length of initial options
data	Buffer for DHCP packet
max_len	Size of DHCP packet buffer

Return values

rc	Return status code

Creates a DHCP packet in the specified buffer, and initialise a DHCP packet structure.

Definition at line 944 of file dhcp.c.

                                                      {
        struct dhcphdr *dhcphdr = data;
        int rc;

        /* Sanity check */
        if ( max_len < ( sizeof ( *dhcphdr ) + options_len ) )
                return -ENOSPC;

        /* Initialise DHCP packet content */
        memset ( dhcphdr, 0, max_len );
        dhcphdr->xid = xid;
        dhcphdr->magic = htonl ( DHCP_MAGIC_COOKIE );
        dhcphdr->htype = ntohs ( netdev->ll_protocol->ll_proto );
        dhcphdr->op = dhcp_op[msgtype];
        dhcphdr->hlen = netdev->ll_protocol->ll_addr_len;
        memcpy ( dhcphdr->chaddr, netdev->ll_addr,
                 netdev->ll_protocol->ll_addr_len );
        memcpy ( dhcphdr->options, options, options_len );

        /* If the local link-layer address functions only as a name
         * (i.e. cannot be used as a destination address), then
         * request broadcast responses.
         */
        if ( netdev->ll_protocol->flags & LL_NAME_ONLY )
                dhcphdr->flags |= htons ( BOOTP_FL_BROADCAST );

        /* If the network device already has an IPv4 address then
         * unicast responses from the DHCP server may be rejected, so
         * request broadcast responses.
         */
        if ( ipv4_has_any_addr ( netdev ) )
                dhcphdr->flags |= htons ( BOOTP_FL_BROADCAST );

        /* 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;
}

References BOOTP_FL_BROADCAST, dhcphdr::chaddr, data, DHCP_MAGIC_COOKIE, DHCP_MESSAGE_TYPE, dhcp_op, dhcppkt_init(), dhcppkt_store(), ENOSPC, ll_protocol::flags, dhcphdr::flags, dhcphdr::hlen, htonl, htons, dhcphdr::htype, ipv4_has_any_addr(), net_device::ll_addr, ll_protocol::ll_addr_len, LL_NAME_ONLY, ll_protocol::ll_proto, net_device::ll_protocol, dhcphdr::magic, max_len, memcpy(), memset(), netdev, ntohs, dhcphdr::op, options, dhcphdr::options, rc, and dhcphdr::xid.

Referenced by create_fakedhcpack(), create_fakepxebsack(), and dhcp_create_request().

dhcp_create_request()

int dhcp_create_request	(	struct dhcp_packet *	dhcppkt,
		struct net_device *	netdev,
		unsigned int	msgtype,
		uint32_t	xid,
		struct in_addr	ciaddr,
		void *	data,
		size_t	max_len
	)

Create DHCP request packet.

Parameters

dhcppkt	DHCP packet structure to fill in
netdev	Network device
msgtype	DHCP message type
xid	Transaction ID (in network-endian order)
ciaddr	Client IP address
data	Buffer for DHCP packet
max_len	Size of DHCP packet buffer

Return values

rc	Return status code

Creates a DHCP request packet in the specified buffer, and initialise a DHCP packet structure.

Definition at line 1007 of file dhcp.c.

                                                       {
        struct dhcp_netdev_desc dhcp_desc;
        struct dhcp_client_id client_id;
        struct dhcp_client_uuid client_uuid;
        const struct setting *setting;
        uint8_t *dhcp_features;
        size_t dhcp_features_len;
        size_t ll_addr_len;
        void *raw;
        ssize_t len;
        unsigned int i;
        int rc;

        /* Create DHCP packet */
        if ( ( rc = dhcp_create_packet ( dhcppkt, netdev, msgtype, xid,
                                         dhcp_request_options_data,
                                         sizeof ( dhcp_request_options_data ),
                                         data, max_len ) ) != 0 ) {
                DBG ( "DHCP could not create DHCP packet: %s\n",
                      strerror ( rc ) );
                goto err_create_packet;
        }

        /* 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 ) );
                goto err_store_features;
        }

        /* Add options to identify the network device */
        fetch_raw_setting ( netdev_settings ( netdev ), &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 ) );
                goto err_store_busid;
        }

        /* 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 ) );
                goto err_store_client_id;
        }

        /* Add client UUID, if we have one.  Required for PXE.  The
         * PXE spec does not specify a byte ordering for UUIDs, but
         * RFC4578 suggests that it follows the EFI spec, in which the
         * first three fields are little-endian.
         */
        client_uuid.type = DHCP_CLIENT_UUID_TYPE;
        if ( ( len = fetch_uuid_setting ( NULL, &uuid_setting,
                                          &client_uuid.uuid ) ) >= 0 ) {
                uuid_mangle ( &client_uuid.uuid );
                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 ) );
                        goto err_store_client_uuid;
                }
        }

        /* Add request settings, if applicable */
        for ( i = 0 ; i < ( sizeof ( dhcp_request_settings ) /
                            sizeof ( dhcp_request_settings[0] ) ) ; i++ ) {
                setting = dhcp_request_settings[i];
                if ( ( len = fetch_raw_setting_copy ( NULL, setting,
                                                      &raw ) ) >= 0 ) {
                        rc = dhcppkt_store ( dhcppkt, setting->tag, raw, len );
                        free ( raw );
                        if ( rc != 0 ) {
                                DBG ( "DHCP could not set %s: %s\n",
                                      setting->name, strerror ( rc ) );
                                goto err_store_raw;
                        }
                }
        }

 err_store_raw:
 err_store_client_uuid:
 err_store_client_id:
 err_store_busid:
 err_store_features:
 err_create_packet:
        return rc;
}

References assert(), dhcphdr::ciaddr, data, DBG, DHCP_CLIENT_ID, DHCP_CLIENT_UUID, DHCP_CLIENT_UUID_TYPE, dhcp_create_packet(), DHCP_EB_BUS_ID, DHCP_EB_ENCAP, DHCP_FEATURES, dhcp_request_options_data, dhcp_request_settings, dhcp_packet::dhcphdr, dhcppkt_store(), fetch_raw_setting(), fetch_raw_setting_copy(), fetch_uuid_setting(), free, len, dhcp_client_id::ll_addr, net_device::ll_addr, ll_protocol::ll_addr_len, ll_protocol::ll_proto, dhcp_client_id::ll_proto, net_device::ll_protocol, max_len, memcpy(), setting::name, netdev, netdev_settings(), ntohs, NULL, raw, rc, strerror(), table_num_entries, table_start, setting::tag, dhcp_client_uuid::type, dhcp_client_uuid::uuid, and uuid_mangle().

Referenced by create_fakedhcpdiscover(), and dhcp_tx().

dhcp_deliver()

static int dhcp_deliver ( struct dhcp_session *  dhcp, struct io_buffer *  iobuf, struct xfer_metadata *  meta  )

static

Receive new data.

Parameters

dhcp	DHCP session
iobuf	I/O buffer
meta	Transfer metadata

Return values

rc	Return status code

Definition at line 1196 of file dhcp.c.

                                                       {
        struct net_device *netdev = dhcp->netdev;
        struct ll_protocol *ll_protocol = netdev->ll_protocol;
        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 };
        struct in_addr pseudo_id;
        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 ) );

        /* Identify server pseudo-ID */
        pseudo_id = server_id;
        if ( ! pseudo_id.s_addr )
                pseudo_id = dhcppkt->dhcphdr->siaddr;
        if ( ! pseudo_id.s_addr )
                pseudo_id = peer->sin_addr;

        /* Check for matching transaction ID */
        if ( dhcphdr->xid != dhcp->xid ) {
                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;
        };

        /* Check for matching client hardware address */
        if ( memcmp ( dhcphdr->chaddr, netdev->ll_addr,
                      ll_protocol->ll_addr_len ) != 0 ) {
                DBGC ( dhcp, "DHCP %p %s from %s:%d has bad chaddr %s\n",
                       dhcp, dhcp_msgtype_name ( msgtype ),
                       inet_ntoa ( peer->sin_addr ), ntohs ( peer->sin_port ),
                       ll_protocol->ntoa ( dhcphdr->chaddr ) );
                rc = -EINVAL;
                goto err_chaddr;
        }

        /* Handle packet based on current state */
        dhcp->state->rx ( dhcp, dhcppkt, peer, msgtype, server_id, pseudo_id );

 err_chaddr:
 err_xid:
        dhcppkt_put ( dhcppkt );
 err_alloc_dhcppkt:
 err_no_src:
        free_iob ( iobuf );
        return rc;
}

References dhcphdr::chaddr, io_buffer::data, data_len, DBGC, DHCP_MESSAGE_TYPE, dhcp_msgtype_name(), DHCP_SERVER_IDENTIFIER, dhcp_packet::dhcphdr, dhcppkt_fetch(), dhcppkt_init(), dhcppkt_put(), EINVAL, ENOMEM, free_iob(), inet_ntoa(), iob_len(), net_device::ll_addr, ll_protocol::ll_addr_len, net_device::ll_protocol, memcmp(), memcpy(), meta(), netdev, dhcp_session::netdev, ll_protocol::ntoa, ntohs, peer, rc, dhcp_session_state::rx, in_addr::s_addr, dhcphdr::siaddr, dhcp_session::state, dhcp_session::xid, dhcphdr::xid, and zalloc().

dhcp_timer_expired()

static void dhcp_timer_expired ( struct retry_timer *  timer, int  fail  )

static

Handle DHCP retry timer expiry.

Parameters

timer	DHCP retry timer
fail	Failure indicator

Definition at line 1297 of file dhcp.c.

                                                                       {
        struct dhcp_session *dhcp =
                container_of ( timer, struct dhcp_session, timer );

        /* If we have failed, terminate DHCP */
        if ( fail ) {
                dhcp_finished ( dhcp, -ETIMEDOUT );
                return;
        }

        /* Increment transmission counter */
        dhcp->count++;

        /* Handle timer expiry based on current state */
        dhcp->state->expired ( dhcp );
}

References container_of, dhcp_session::count, dhcp_finished(), ETIMEDOUT, dhcp_session_state::expired, and dhcp_session::state.

Referenced by start_dhcp(), and start_pxebs().

start_dhcp()

int start_dhcp	(	struct interface *	job,
		struct net_device *	netdev
	)

Start DHCP state machine on a network device.

Parameters

job	Job control interface
netdev	Network device

Return values

rc	Return status code

Starts DHCP on the specified network device. If successful, the DHCPACK (and ProxyDHCPACK, if applicable) will be registered as option sources.

Definition at line 1357 of file dhcp.c.

                                                                    {
        struct dhcp_session *dhcp;
        int rc;

        /* Allocate and initialise structure */
        dhcp = zalloc ( sizeof ( *dhcp ) );
        if ( ! dhcp )
                return -ENOMEM;
        ref_init ( &dhcp->refcnt, dhcp_free );
        intf_init ( &dhcp->job, &dhcp_job_desc, &dhcp->refcnt );
        intf_init ( &dhcp->xfer, &dhcp_xfer_desc, &dhcp->refcnt );
        timer_init ( &dhcp->timer, dhcp_timer_expired, &dhcp->refcnt );
        dhcp->netdev = netdev_get ( netdev );
        dhcp->local.sin_family = AF_INET;
        dhcp->local.sin_port = htons ( BOOTPC_PORT );
        dhcp->xid = random();

        /* Store DHCP transaction ID for fakedhcp code */
        dhcp_last_xid = dhcp->xid;

        /* 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 */
        intf_plug_plug ( &dhcp->job, job );
        ref_put ( &dhcp->refcnt );
        return 0;

 err:
        dhcp_finished ( dhcp, rc );
        ref_put ( &dhcp->refcnt );
        return rc;
}

References AF_INET, BOOTPC_PORT, dhcp_finished(), dhcp_free(), dhcp_job_desc, dhcp_last_xid, dhcp_peer, dhcp_set_state(), dhcp_state_discover, dhcp_timer_expired(), dhcp_xfer_desc, ENOMEM, htons, intf_init(), intf_plug_plug(), dhcp_session::job, dhcp_session::local, netdev, dhcp_session::netdev, netdev_get(), random(), rc, ref_init, ref_put, dhcp_session::refcnt, sockaddr_in::sin_family, sockaddr_in::sin_port, SOCK_DGRAM, dhcp_session::timer, dhcp_session::xfer, xfer_open_socket(), dhcp_session::xid, and zalloc().

pxebs_list()

static void pxebs_list ( struct dhcp_session *  dhcp, void *  raw, size_t  raw_len, struct in_addr *  ip  )

static

Retrieve list of PXE boot servers for a given server type.

Parameters

dhcp	DHCP session
raw	DHCP PXE boot server list
raw_len	Length of DHCP PXE boot server list
ip	IP address list to fill in

The caller must ensure that the IP address list has sufficient space.

Definition at line 1407 of file dhcp.c.

                                                              {
        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;
        }
}

References DBGC, ip, dhcp_pxe_boot_server::ip, dhcp_pxe_boot_server::num_ip, offsetof, dhcp_session::pxe_type, raw, raw_len, dhcp_pxe_boot_server::type, and typeof().

Referenced by start_pxebs().

start_pxebs()

int start_pxebs	(	struct interface *	job,
		struct net_device *	netdev,
		unsigned int	pxe_type
	)

Start PXE Boot Server Discovery on a network device.

Parameters

job	Job control interface
netdev	Network device
pxe_type	PXE server type

Return values

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.

Definition at line 1447 of file dhcp.c.

                                          {
        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_raw_setting ( NULL, &pxe_boot_servers_setting,
                                             NULL, 0 );
        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;
        ref_init ( &dhcp->refcnt, dhcp_free );
        intf_init ( &dhcp->job, &dhcp_job_desc, &dhcp->refcnt );
        intf_init ( &dhcp->xfer, &dhcp_xfer_desc, &dhcp->refcnt );
        timer_init ( &dhcp->timer, dhcp_timer_expired, &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 );

        /* 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_raw_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 */
        intf_plug_plug ( &dhcp->job, job );
        ref_put ( &dhcp->refcnt );
        return 0;

 err:
        dhcp_finished ( dhcp, rc );
        ref_put ( &dhcp->refcnt );
        return rc;
}

References AF_INET, BOOTPC_PORT, cpu_to_le16, DBGC, dhcp_finished(), dhcp_free(), dhcp_job_desc, dhcp_peer, DHCP_PXE_BOOT_SERVER_MCAST, DHCP_PXE_BOOT_SERVERS, DHCP_PXE_DISCOVERY_CONTROL, dhcp_set_state(), dhcp_state_pxebs, dhcp_timer_expired(), dhcp_xfer_desc, EINVAL, ENOMEM, fetch_ipv4_setting(), fetch_raw_setting(), fetch_uintz_setting(), htons, INADDR_BROADCAST, inet_ntoa(), intf_init(), intf_plug_plug(), ip, dhcp_session::job, dhcp_session::local, netdev, dhcp_session::netdev, netdev_get(), netdev_settings(), NULL, dhcp_session::pxe_accept, dhcp_session::pxe_attempt, dhcp_session::pxe_type, pxebs_list(), PXEBS_NO_BROADCAST, PXEBS_NO_MULTICAST, PXEBS_NO_UNKNOWN_SERVERS, rc, ref_init, ref_put, dhcp_session::refcnt, in_addr::s_addr, sockaddr_in::sin_addr, sockaddr_in::sin_family, sockaddr_in::sin_port, SOCK_DGRAM, setting::tag, dhcp_session::timer, dhcp_session::xfer, xfer_open_socket(), and zalloc().

Referenced by pxebs().

Variable Documentation

dhcp_op

const uint8_t dhcp_op[]

static

Initial value:

= {
        [DHCPDISCOVER]  = BOOTP_REQUEST,
        [DHCPOFFER]     = BOOTP_REPLY,
        [DHCPREQUEST]   = BOOTP_REQUEST,
        [DHCPDECLINE]   = BOOTP_REQUEST,
        [DHCPACK]       = BOOTP_REPLY,
        [DHCPNAK]       = BOOTP_REPLY,
        [DHCPRELEASE]   = BOOTP_REQUEST,
        [DHCPINFORM]    = BOOTP_REQUEST,
}

DHCP operation types.

This table maps from DHCP message types (i.e. values of the DHCP_MESSAGE_TYPE option) to values of the "op" field within a DHCP packet.

Definition at line 69 of file dhcp.c.

Referenced by dhcp_create_packet().

dhcp_request_options_data

uint8_t dhcp_request_options_data[]

static

Initial value:

= {
        DHCP_MESSAGE_TYPE, DHCP_BYTE ( 0 ),
        DHCP_MAX_MESSAGE_SIZE,
        DHCP_WORD ( ETH_MAX_MTU - 20  - 8  ),
        DHCP_CLIENT_ARCHITECTURE, DHCP_WORD ( DHCP_ARCH_CLIENT_ARCHITECTURE ),
        DHCP_CLIENT_NDI, DHCP_OPTION ( DHCP_ARCH_CLIENT_NDI ),
        DHCP_VENDOR_CLASS_ID,
        DHCP_STRING ( DHCP_VENDOR_PXECLIENT ( DHCP_ARCH_CLIENT_ARCHITECTURE,
                                              DHCP_ARCH_CLIENT_NDI ) ),
        DHCP_USER_CLASS_ID, DHCP_STRING ( 'i', '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_MTU, DHCP_NTP_SERVERS,
                      DHCP_VENDOR_ENCAP, DHCP_VENDOR_CLASS_ID,
                      DHCP_TFTP_SERVER_NAME, DHCP_BOOTFILE_NAME,
                      DHCP_DOMAIN_SEARCH,
                      128, 129, 130, 131, 132, 133, 134, 135, 
                      DHCP_EB_ENCAP, DHCP_ISCSI_INITIATOR_IQN ),
        DHCP_END
}

Raw option data for options common to all DHCP requests.

Definition at line 81 of file dhcp.c.

Referenced by dhcp_create_request().

dhcp_request_settings

const struct setting* dhcp_request_settings[]

static

Initial value:

= {
        &user_class_setting,
        &vendor_class_setting,
}

Settings copied in to all DHCP requests.

Definition at line 104 of file dhcp.c.

Referenced by dhcp_create_request().

dhcp_last_xid

uint32_t dhcp_last_xid

Most recent DHCP transaction ID.

This is exposed for use by the fakedhcp code when reconstructing DHCP packets for PXE NBPs.

Definition at line 124 of file dhcp.c.

Referenced by create_fakedhcpack(), create_fakedhcpdiscover(), create_fakepxebsack(), and start_dhcp().

dhcp_state_discover

static struct dhcp_session_state dhcp_state_discover

static

Initial value:

= {
        .name                   = "discovery",
        .tx                     = dhcp_discovery_tx,
        .rx                     = dhcp_discovery_rx,
        .expired                = dhcp_discovery_expired,
        .tx_msgtype             = DHCPDISCOVER,
        .min_timeout_sec        = DHCP_DISC_START_TIMEOUT_SEC,
        .max_timeout_sec        = DHCP_DISC_END_TIMEOUT_SEC,
}

DHCP discovery state operations.

Definition at line 194 of file dhcp.c.

Referenced by dhcp_defer(), and start_dhcp().

dhcp_state_request

static struct dhcp_session_state dhcp_state_request

static

Initial value:

= {
        .name                   = "request",
        .tx                     = dhcp_request_tx,
        .rx                     = dhcp_request_rx,
        .expired                = dhcp_request_expired,
        .tx_msgtype             = DHCPREQUEST,
        .min_timeout_sec        = DHCP_REQ_START_TIMEOUT_SEC,
        .max_timeout_sec        = DHCP_REQ_END_TIMEOUT_SEC,
}

DHCP request state operations.

Definition at line 195 of file dhcp.c.

Referenced by dhcp_discovery_expired(), and dhcp_discovery_rx().

dhcp_state_proxy

static struct dhcp_session_state dhcp_state_proxy

static

Initial value:

= {
        .name                   = "ProxyDHCP",
        .tx                     = dhcp_proxy_tx,
        .rx                     = dhcp_proxy_rx,
        .expired                = dhcp_proxy_expired,
        .tx_msgtype             = DHCPREQUEST,
        .min_timeout_sec        = DHCP_PROXY_START_TIMEOUT_SEC,
        .max_timeout_sec        = DHCP_PROXY_END_TIMEOUT_SEC,
}

ProxyDHCP request state operations.

Definition at line 196 of file dhcp.c.

Referenced by dhcp_request_rx().

dhcp_state_pxebs

static struct dhcp_session_state dhcp_state_pxebs

static

Initial value:

= {
        .name                   = "PXEBS",
        .tx                     = dhcp_pxebs_tx,
        .rx                     = dhcp_pxebs_rx,
        .expired                = dhcp_pxebs_expired,
        .tx_msgtype             = DHCPREQUEST,
        .min_timeout_sec        = PXEBS_START_TIMEOUT_SEC,
        .max_timeout_sec        = PXEBS_END_TIMEOUT_SEC,
}

PXE Boot Server Discovery state operations.

Definition at line 197 of file dhcp.c.

Referenced by dhcp_pxebs_expired(), and start_pxebs().

dhcp_xfer_operations

struct interface_operation dhcp_xfer_operations[]

static

Initial value:

= {
        INTF_OP ( xfer_deliver, struct dhcp_session *, dhcp_deliver ),
}

DHCP data transfer interface operations.

Definition at line 1283 of file dhcp.c.

dhcp_xfer_desc

struct interface_descriptor dhcp_xfer_desc

static

Initial value:

=
        INTF_DESC ( struct dhcp_session, xfer, dhcp_xfer_operations )

DHCP data transfer interface descriptor.

Definition at line 1288 of file dhcp.c.

Referenced by start_dhcp(), and start_pxebs().

dhcp_job_op

struct interface_operation dhcp_job_op[]

static

Initial value:

= {
        INTF_OP ( intf_close, struct dhcp_session *, dhcp_finished ),
}

DHCP job control interface operations.

Definition at line 1321 of file dhcp.c.

dhcp_job_desc

struct interface_descriptor dhcp_job_desc

static

Initial value:

=
        INTF_DESC ( struct dhcp_session, job, dhcp_job_op )

DHCP job control interface descriptor.

Definition at line 1326 of file dhcp.c.

Referenced by start_dhcp(), and start_pxebs().

dhcp_peer

struct sockaddr dhcp_peer

static

Initial value:

= {
        .sa_family = AF_INET,
}

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.

Definition at line 1342 of file dhcp.c.

Referenced by start_dhcp(), and start_pxebs().

__net_device_configurator

struct net_device_configurator dhcp_configurator __net_device_configurator

Initial value:

= {
        .name = "dhcp",
        .start = start_dhcp,
}

DHCP network device configurator.

Definition at line 1544 of file dhcp.c.