fakedhcp.h File Reference

Fake DHCP packets. More...

#include <stdint.h>

Go to the source code of this file.

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
int	create_fakedhcpdiscover (struct net_device *netdev, void *data, size_t max_len)
	Create fake DHCPDISCOVER packet. More...
int	create_fakedhcpack (struct net_device *netdev, void *data, size_t max_len)
	Create fake DHCPACK packet. More...
int	create_fakepxebsack (struct net_device *netdev, void *data, size_t max_len)
	Create fake PXE Boot Server ACK packet. More...

Detailed Description

Fake DHCP packets.

Definition in file fakedhcp.h.

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

create_fakedhcpdiscover()

int create_fakedhcpdiscover	(	struct net_device *	netdev,
		void *	data,
		size_t	max_len
	)

Create fake DHCPDISCOVER packet.

Parameters

netdev	Network device
data	Buffer for DHCP packet
max_len	Size of DHCP packet buffer

Return values

rc	Return status code

Used by external code.

Definition at line 109 of file fakedhcp.c.

                                                           {
        struct dhcp_packet dhcppkt;
        struct in_addr ciaddr = { 0 };
        int rc;

        if ( ( rc = dhcp_create_request ( &dhcppkt, netdev, DHCPDISCOVER,
                                          dhcp_last_xid, ciaddr, data,
                                          max_len ) ) != 0 ) {
                DBG ( "Could not create DHCPDISCOVER: %s\n",
                      strerror ( rc ) );
                return rc;
        }

        return 0;
}

References data, DBG, dhcp_create_request(), dhcp_last_xid, DHCPDISCOVER, netdev, rc, and strerror().

Referenced by efi_pxe_fake_all().

create_fakedhcpack()

int create_fakedhcpack	(	struct net_device *	netdev,
		void *	data,
		size_t	max_len
	)

Create fake DHCPACK packet.

Parameters

netdev	Network device
data	Buffer for DHCP packet
max_len	Size of DHCP packet buffer

Return values

rc	Return status code

Used by external code.

Definition at line 136 of file fakedhcp.c.

                                                      {
        struct dhcp_packet dhcppkt;
        int rc;

        /* Create base DHCPACK packet */
        if ( ( rc = dhcp_create_packet ( &dhcppkt, netdev, DHCPACK,
                                         dhcp_last_xid, NULL, 0,
                                         data, max_len ) ) != 0 ) {
                DBG ( "Could not create DHCPACK: %s\n", strerror ( rc ) );
                return rc;
        }

        /* Merge in globally-scoped settings, then netdev-specific
         * settings.  Do it in this order so that netdev-specific
         * settings take precedence regardless of stated priorities.
         */
        if ( ( rc = copy_settings ( &dhcppkt, NULL ) ) != 0 ) {
                DBG ( "Could not set DHCPACK global settings: %s\n",
                      strerror ( rc ) );
                return rc;
        }
        if ( ( rc = copy_settings ( &dhcppkt,
                                    netdev_settings ( netdev ) ) ) != 0 ) {
                DBG ( "Could not set DHCPACK netdev settings: %s\n",
                      strerror ( rc ) );
                return rc;
        }

        return 0;
}

References copy_settings(), data, DBG, dhcp_create_packet(), dhcp_last_xid, DHCPACK, netdev, netdev_settings(), NULL, rc, and strerror().

Referenced by create_fakepxebsack(), efi_pxe_fake_all(), and nbi_prepare_dhcp().

create_fakepxebsack()

int create_fakepxebsack	(	struct net_device *	netdev,
		void *	data,
		size_t	max_len
	)

Create fake PXE Boot Server ACK packet.

Parameters

netdev	Network device
data	Buffer for DHCP packet
max_len	Size of DHCP packet buffer

Return values

rc	Return status code

Used by external code.

Definition at line 178 of file fakedhcp.c.

                                                       {
        struct dhcp_packet dhcppkt;
        struct settings *proxy_settings;
        struct settings *pxebs_settings;
        int rc;

        /* Identify available settings */
        proxy_settings = find_settings ( PROXYDHCP_SETTINGS_NAME );
        pxebs_settings = find_settings ( PXEBS_SETTINGS_NAME );
        if ( ( ! proxy_settings ) && ( ! pxebs_settings ) ) {
                /* No PXE boot server; return the regular DHCPACK */
                return create_fakedhcpack ( netdev, data, max_len );
        }

        /* Create base DHCPACK packet */
        if ( ( rc = dhcp_create_packet ( &dhcppkt, netdev, DHCPACK,
                                         dhcp_last_xid, NULL, 0,
                                         data, max_len ) ) != 0 ) {
                DBG ( "Could not create PXE BS ACK: %s\n",
                      strerror ( rc ) );
                return rc;
        }

        /* Populate ciaddr */
        fetch_ipv4_setting ( netdev_settings ( netdev ), &ip_setting,
                             &dhcppkt.dhcphdr->ciaddr );

        /* Merge in ProxyDHCP options */
        if ( proxy_settings &&
             ( ( rc = copy_settings ( &dhcppkt, proxy_settings ) ) != 0 ) ) {
                DBG ( "Could not copy ProxyDHCP settings: %s\n",
                      strerror ( rc ) );
                return rc;
        }

        /* Merge in BootServerDHCP options, if present */
        if ( pxebs_settings &&
             ( ( rc = copy_settings ( &dhcppkt, pxebs_settings ) ) != 0 ) ) {
                DBG ( "Could not copy PXE BS settings: %s\n",
                      strerror ( rc ) );
                return rc;
        }

        return 0;
}

References dhcphdr::ciaddr, copy_settings(), create_fakedhcpack(), data, DBG, dhcp_create_packet(), dhcp_last_xid, DHCPACK, dhcp_packet::dhcphdr, fetch_ipv4_setting(), find_settings(), netdev, netdev_settings(), NULL, PROXYDHCP_SETTINGS_NAME, PXEBS_SETTINGS_NAME, rc, and strerror().

Referenced by efi_pxe_fake_all().