pxe_tftp.c File Reference

PXE TFTP API. More...

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <byteswap.h>
#include <ipxe/uaccess.h>
#include <ipxe/in.h>
#include <ipxe/tftp.h>
#include <ipxe/iobuf.h>
#include <ipxe/xfer.h>
#include <ipxe/open.h>
#include <ipxe/process.h>
#include <ipxe/uri.h>
#include <realmode.h>
#include <pxe.h>

Go to the source code of this file.

Data Structures
struct	pxe_tftp_connection
	A PXE TFTP connection. More...

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
static void	pxe_tftp_close (struct pxe_tftp_connection *pxe_tftp, int rc)
	Close PXE TFTP connection. More...
static size_t	pxe_tftp_xfer_window (struct pxe_tftp_connection *pxe_tftp)
	Check flow control window. More...
static int	pxe_tftp_xfer_deliver (struct pxe_tftp_connection *pxe_tftp, struct io_buffer *iobuf, struct xfer_metadata *meta)
	Receive new data. More...
static int	pxe_tftp_open (IP4_t ipaddress, UDP_PORT_t port, UINT8_t *filename, UINT16_t blksize)
	Open PXE TFTP connection. More...
static PXENV_EXIT_t	pxenv_tftp_open (struct s_PXENV_TFTP_OPEN *tftp_open)
	TFTP OPEN. More...
static PXENV_EXIT_t	pxenv_tftp_close (struct s_PXENV_TFTP_CLOSE *tftp_close)
	TFTP CLOSE. More...
static PXENV_EXIT_t	pxenv_tftp_read (struct s_PXENV_TFTP_READ *tftp_read)
	TFTP READ. More...
PXENV_EXIT_t	pxenv_tftp_read_file (struct s_PXENV_TFTP_READ_FILE *tftp_read_file)
	TFTP/MTFTP read file. More...
static PXENV_EXIT_t	pxenv_tftp_get_fsize (struct s_PXENV_TFTP_GET_FSIZE *tftp_get_fsize)
	TFTP GET FILE SIZE. More...

Variables
static struct interface_operation	pxe_tftp_xfer_ops []
	PXE TFTP connection interface operations. More...
static struct interface_descriptor	pxe_tftp_xfer_desc
	PXE TFTP connection interface descriptor. More...
static struct pxe_tftp_connection	pxe_tftp
	The PXE TFTP connection. More...
struct pxe_api_call pxe_tftp_api []	__pxe_api_call
	PXE TFTP API. More...

Detailed Description

PXE TFTP API.

Definition in file pxe_tftp.c.

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

pxe_tftp_close()

static void pxe_tftp_close ( struct pxe_tftp_connection *  pxe_tftp, int  rc  )

static

Close PXE TFTP connection.

Parameters

pxe_tftp	PXE TFTP connection
rc	Final status code

Definition at line 75 of file pxe_tftp.c.

                                                                            {
        intf_shutdown ( &pxe_tftp->xfer, rc );
        pxe_tftp->rc = rc;
}

References intf_shutdown(), pxe_tftp, pxe_tftp_connection::rc, rc, and pxe_tftp_connection::xfer.

Referenced by pxe_tftp_xfer_deliver(), pxenv_tftp_close(), pxenv_tftp_get_fsize(), pxenv_tftp_open(), and pxenv_tftp_read_file().

pxe_tftp_xfer_window()

static size_t pxe_tftp_xfer_window ( struct pxe_tftp_connection *  pxe_tftp )

static

Check flow control window.

Parameters

pxe_tftp

PXE TFTP connection

Return values

len	Length of window

Definition at line 86 of file pxe_tftp.c.

                                                                            {

        return pxe_tftp->blksize;
}

References pxe_tftp_connection::blksize, and pxe_tftp.

pxe_tftp_xfer_deliver()

static int pxe_tftp_xfer_deliver ( struct pxe_tftp_connection *  pxe_tftp, struct io_buffer *  iobuf, struct xfer_metadata *  meta  )

static

Receive new data.

Parameters

pxe_tftp	PXE TFTP connection
iobuf	I/O buffer
meta	Transfer metadata

Return values

rc	Return status code

Definition at line 99 of file pxe_tftp.c.

                                                                {
        size_t len = iob_len ( iobuf );
        int rc = 0;

        /* Calculate new buffer position */
        if ( meta->flags & XFER_FL_ABS_OFFSET )
                pxe_tftp->offset = 0;
        pxe_tftp->offset += meta->offset;

        /* Copy data block to buffer */
        if ( len == 0 ) {
                /* No data (pure seek); treat as success */
        } else if ( pxe_tftp->offset < pxe_tftp->start ) {
                DBG ( " buffer underrun at %zx (min %zx)",
                      pxe_tftp->offset, pxe_tftp->start );
                rc = -ENOBUFS;
        } else if ( ( pxe_tftp->offset + len ) >
                    ( pxe_tftp->start + pxe_tftp->size ) ) {
                DBG ( " buffer overrun at %zx (max %zx)",
                      ( pxe_tftp->offset + len ),
                      ( pxe_tftp->start + pxe_tftp->size ) );
                rc = -ENOBUFS;
        } else {
                copy_to_user ( pxe_tftp->buffer,
                               ( pxe_tftp->offset - pxe_tftp->start ),
                               iobuf->data, len );
        }

        /* Calculate new buffer position */
        pxe_tftp->offset += len;

        /* Record maximum offset as the file size */
        if ( pxe_tftp->max_offset < pxe_tftp->offset )
                pxe_tftp->max_offset = pxe_tftp->offset;

        /* Terminate transfer on error */
        if ( rc != 0 )
                pxe_tftp_close ( pxe_tftp, rc );

        free_iob ( iobuf );
        return rc;
}

References pxe_tftp_connection::buffer, copy_to_user(), io_buffer::data, DBG, ENOBUFS, free_iob(), iob_len(), len, pxe_tftp_connection::max_offset, meta(), pxe_tftp_connection::offset, pxe_tftp, pxe_tftp_close(), rc, pxe_tftp_connection::size, pxe_tftp_connection::start, and XFER_FL_ABS_OFFSET.

pxe_tftp_open()

static int pxe_tftp_open ( IP4_t  ipaddress, UDP_PORT_t  port, UINT8_t *  filename, UINT16_t  blksize  )

static

Open PXE TFTP connection.

Parameters

ipaddress	IP address
port	TFTP server port (in network byte order)
filename	File name
blksize	Requested block size

Return values

rc	Return status code

Definition at line 171 of file pxe_tftp.c.

                                                                 {
        union {
                struct sockaddr sa;
                struct sockaddr_in sin;
        } server;
        struct uri *uri;
        int rc;

        /* Reset PXE TFTP connection structure */
        memset ( &pxe_tftp, 0, sizeof ( pxe_tftp ) );
        intf_init ( &pxe_tftp.xfer, &pxe_tftp_xfer_desc, NULL );
        if ( blksize < TFTP_DEFAULT_BLKSIZE )
                blksize = TFTP_DEFAULT_BLKSIZE;
        pxe_tftp.blksize = blksize;
        pxe_tftp.rc = -EINPROGRESS;

        /* Construct URI */
        memset ( &server, 0, sizeof ( server ) );
        server.sin.sin_family = AF_INET;
        server.sin.sin_addr.s_addr = ipaddress;
        server.sin.sin_port = port;
        DBG ( " %s", sock_ntoa ( &server.sa ) );
        if ( port )
                DBG ( ":%d", ntohs ( port ) );
        DBG ( ":%s", filename );
        uri = pxe_uri ( &server.sa, ( ( char * ) filename ) );
        if ( ! uri ) {
                DBG ( " could not create URI\n" );
                return -ENOMEM;
        }

        /* Open PXE TFTP connection */
        if ( ( rc = xfer_open_uri ( &pxe_tftp.xfer, uri ) ) != 0 ) {
                DBG ( " could not open (%s)\n", strerror ( rc ) );
                return rc;
        }

        return 0;
}

References AF_INET, blksize, pxe_tftp_connection::blksize, DBG, EINPROGRESS, ENOMEM, intf_init(), memset(), ntohs, NULL, port, pxe_tftp, pxe_tftp_xfer_desc, pxe_uri(), pxe_tftp_connection::rc, rc, sa, sin, sock_ntoa(), strerror(), TFTP_DEFAULT_BLKSIZE, pxe_tftp_connection::xfer, and xfer_open_uri().

Referenced by pxenv_tftp_get_fsize(), pxenv_tftp_open(), and pxenv_tftp_read_file().

pxenv_tftp_open()

static PXENV_EXIT_t pxenv_tftp_open ( struct s_PXENV_TFTP_OPEN *  tftp_open )

static

TFTP OPEN.

Parameters

tftp_open	Pointer to a struct s_PXENV_TFTP_OPEN
s_PXENV_TFTP_OPEN::ServerIPAddress	TFTP server IP address
s_PXENV_TFTP_OPEN::GatewayIPAddress	Relay agent IP address, or 0.0.0.0
s_PXENV_TFTP_OPEN::FileName	Name of file to open
s_PXENV_TFTP_OPEN::TFTPPort	TFTP server UDP port
s_PXENV_TFTP_OPEN::PacketSize	TFTP blksize option to request

Return values

PXENV_EXIT_SUCCESS	File was opened
PXENV_EXIT_FAILURE	File was not opened
s_PXENV_TFTP_OPEN::Status	PXE status code
s_PXENV_TFTP_OPEN::PacketSize	Negotiated blksize

Exceptions

PXENV_STATUS_TFTP_INVALID_PACKET_SIZE

Requested blksize too small

Opens a TFTP connection for downloading a file a block at a time using pxenv_tftp_read().

If s_PXENV_TFTP_OPEN::GatewayIPAddress is 0.0.0.0, normal IP routing will take place. See the relevant implementation note for more details.

On x86, you must set the s_PXE::StatusCallout field to a nonzero value before calling this function in protected mode. You cannot call this function with a 32-bit stack segment. (See the relevant implementation note for more details.)

Note

According to the PXE specification version 2.1, this call "opens a file for reading/writing", though how writing is to be achieved without the existence of an API call pxenv_tftp_write() is not made clear.

Despite the existence of the numerous statements within the PXE specification of the form "...if a TFTP/MTFTP or UDP connection is active...", you cannot use pxenv_tftp_open() and pxenv_tftp_read() to read a file via MTFTP; only via plain old TFTP. If you want to use MTFTP, use pxenv_tftp_read_file() instead. Astute readers will note that, since pxenv_tftp_read_file() is an atomic operation from the point of view of the PXE API, it is conceptually impossible to issue any other PXE API call "if an MTFTP connection is active".

Definition at line 254 of file pxe_tftp.c.

                                                                            {
        int rc;

        DBG ( "PXENV_TFTP_OPEN" );

        /* Guard against callers that fail to close before re-opening */
        pxe_tftp_close ( &pxe_tftp, 0 );

        /* Open connection */
        if ( ( rc = pxe_tftp_open ( tftp_open->ServerIPAddress,
                                    tftp_open->TFTPPort,
                                    tftp_open->FileName,
                                    tftp_open->PacketSize ) ) != 0 ) {
                tftp_open->Status = PXENV_STATUS ( rc );
                return PXENV_EXIT_FAILURE;
        }

        /* Wait for OACK to arrive so that we have the block size */
        while ( ( ( rc = pxe_tftp.rc ) == -EINPROGRESS ) &&
                ( pxe_tftp.max_offset == 0 ) ) {
                step();
        }
        pxe_tftp.blksize = xfer_window ( &pxe_tftp.xfer );
        tftp_open->PacketSize = pxe_tftp.blksize;
        DBG ( " blksize=%d", tftp_open->PacketSize );

        /* EINPROGRESS is normal; we don't wait for the whole transfer */
        if ( rc == -EINPROGRESS )
                rc = 0;

        tftp_open->Status = PXENV_STATUS ( rc );
        return ( rc ? PXENV_EXIT_FAILURE : PXENV_EXIT_SUCCESS );
}

References pxe_tftp_connection::blksize, DBG, EINPROGRESS, pxe_tftp_connection::max_offset, pxe_tftp, pxe_tftp_close(), pxe_tftp_open(), PXENV_EXIT_FAILURE, PXENV_EXIT_SUCCESS, PXENV_STATUS, pxe_tftp_connection::rc, rc, step(), tftp_open(), pxe_tftp_connection::xfer, and xfer_window().

pxenv_tftp_close()

static PXENV_EXIT_t pxenv_tftp_close ( struct s_PXENV_TFTP_CLOSE *  tftp_close )

static

TFTP CLOSE.

Parameters

tftp_close

Pointer to a struct s_PXENV_TFTP_CLOSE

Return values

PXENV_EXIT_SUCCESS	File was closed successfully
PXENV_EXIT_FAILURE	File was not closed
s_PXENV_TFTP_CLOSE::Status	PXE status code

Exceptions

None

-

Close a connection previously opened with pxenv_tftp_open(). You must have previously opened a connection with pxenv_tftp_open().

On x86, you must set the s_PXE::StatusCallout field to a nonzero value before calling this function in protected mode. You cannot call this function with a 32-bit stack segment. (See the relevant implementation note for more details.)

Definition at line 305 of file pxe_tftp.c.

                                                                               {
        DBG ( "PXENV_TFTP_CLOSE" );

        pxe_tftp_close ( &pxe_tftp, 0 );
        tftp_close->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}

References DBG, pxe_tftp, pxe_tftp_close(), PXENV_EXIT_SUCCESS, PXENV_STATUS_SUCCESS, and tftp_close().

pxenv_tftp_read()

static PXENV_EXIT_t pxenv_tftp_read ( struct s_PXENV_TFTP_READ *  tftp_read )

static

TFTP READ.

Parameters

tftp_read	Pointer to a struct s_PXENV_TFTP_READ
s_PXENV_TFTP_READ::Buffer	Address of data buffer

Return values

PXENV_EXIT_SUCCESS	Data was read successfully
PXENV_EXIT_FAILURE	Data was not read
s_PXENV_TFTP_READ::Status	PXE status code
s_PXENV_TFTP_READ::PacketNumber	TFTP packet number
s_PXENV_TFTP_READ::BufferSize	Length of data written into buffer

Reads a single packet from a connection previously opened with pxenv_tftp_open() into the data buffer pointed to by s_PXENV_TFTP_READ::Buffer. You must have previously opened a connection with pxenv_tftp_open(). The data written into s_PXENV_TFTP_READ::Buffer is just the file data; the various network headers have already been removed.

The buffer must be large enough to contain a packet of the size negotiated via the s_PXENV_TFTP_OPEN::PacketSize field in the pxenv_tftp_open() call. It is worth noting that the PXE specification does not require the caller to fill in s_PXENV_TFTP_READ::BufferSize before calling pxenv_tftp_read(), so the PXE stack is free to ignore whatever value the caller might place there and just assume that the buffer is large enough. That said, it may be worth the caller always filling in s_PXENV_TFTP_READ::BufferSize to guard against PXE stacks that mistake it for an input parameter.

The length of the TFTP data packet will be returned via s_PXENV_TFTP_READ::BufferSize. If this length is less than the blksize negotiated via s_PXENV_TFTP_OPEN::PacketSize in the call to pxenv_tftp_open(), this indicates that the block is the last block in the file. Note that zero is a valid length for s_PXENV_TFTP_READ::BufferSize, and will occur when the length of the file is a multiple of the blksize.

The PXE specification doesn't actually state that calls to pxenv_tftp_read() will return the data packets in strict sequential order, though most PXE stacks will probably do so. The sequence number of the packet will be returned in s_PXENV_TFTP_READ::PacketNumber. The first packet in the file has a sequence number of one, not zero.

To guard against flawed PXE stacks, the caller should probably set s_PXENV_TFTP_READ::PacketNumber to one less than the expected returned value (i.e. set it to zero for the first call to pxenv_tftp_read() and then re-use the returned s_PXENV_TFTP_READ parameter block for subsequent calls without modifying s_PXENV_TFTP_READ::PacketNumber between calls). The caller should also guard against potential problems caused by flawed implementations returning the occasional duplicate packet, by checking that the value returned in s_PXENV_TFTP_READ::PacketNumber is as expected (i.e. one greater than that returned from the previous call to pxenv_tftp_read()).

On x86, you must set the s_PXE::StatusCallout field to a nonzero value before calling this function in protected mode. You cannot call this function with a 32-bit stack segment. (See the relevant implementation note for more details.)

Definition at line 374 of file pxe_tftp.c.

                                                                            {
        int rc;

        DBG ( "PXENV_TFTP_READ to %04x:%04x",
              tftp_read->Buffer.segment, tftp_read->Buffer.offset );

        /* Read single block into buffer */
        pxe_tftp.buffer = real_to_user ( tftp_read->Buffer.segment,
                                         tftp_read->Buffer.offset );
        pxe_tftp.size = pxe_tftp.blksize;
        pxe_tftp.start = pxe_tftp.offset;
        while ( ( ( rc = pxe_tftp.rc ) == -EINPROGRESS ) &&
                ( pxe_tftp.offset == pxe_tftp.start ) )
                step();
        pxe_tftp.buffer = UNULL;
        tftp_read->BufferSize = ( pxe_tftp.offset - pxe_tftp.start );
        tftp_read->PacketNumber = ++pxe_tftp.blkidx;

        /* EINPROGRESS is normal if we haven't reached EOF yet */
        if ( rc == -EINPROGRESS )
                rc = 0;

        tftp_read->Status = PXENV_STATUS ( rc );
        return ( rc ? PXENV_EXIT_FAILURE : PXENV_EXIT_SUCCESS );
}

References pxe_tftp_connection::blkidx, pxe_tftp_connection::blksize, pxe_tftp_connection::buffer, s_PXENV_TFTP_READ::Buffer, s_PXENV_TFTP_READ::BufferSize, DBG, EINPROGRESS, pxe_tftp_connection::offset, s_PXENV_TFTP_READ::PacketNumber, pxe_tftp, PXENV_EXIT_FAILURE, PXENV_EXIT_SUCCESS, PXENV_STATUS, pxe_tftp_connection::rc, rc, real_to_user(), pxe_tftp_connection::size, pxe_tftp_connection::start, s_PXENV_TFTP_READ::Status, step(), and UNULL.

pxenv_tftp_read_file()

PXENV_EXIT_t pxenv_tftp_read_file

(

struct s_PXENV_TFTP_READ_FILE *

tftp_read_file

)

TFTP/MTFTP read file.

Parameters

tftp_read_file	Pointer to a struct s_PXENV_TFTP_READ_FILE
s_PXENV_TFTP_READ_FILE::FileName	File name
s_PXENV_TFTP_READ_FILE::BufferSize	Size of the receive buffer
s_PXENV_TFTP_READ_FILE::Buffer	Address of the receive buffer
s_PXENV_TFTP_READ_FILE::ServerIPAddress	TFTP server IP address
s_PXENV_TFTP_READ_FILE::GatewayIPAddress	Relay agent IP address
s_PXENV_TFTP_READ_FILE::McastIPAddress	File's multicast IP address
s_PXENV_TFTP_READ_FILE::TFTPClntPort	Client multicast UDP port
s_PXENV_TFTP_READ_FILE::TFTPSrvPort	Server multicast UDP port
s_PXENV_TFTP_READ_FILE::TFTPOpenTimeOut	Time to wait for first packet
s_PXENV_TFTP_READ_FILE::TFTPReopenDelay	MTFTP inactivity timeout

Return values

PXENV_EXIT_SUCCESS	File downloaded successfully
PXENV_EXIT_FAILURE	File not downloaded
s_PXENV_TFTP_READ_FILE::Status	PXE status code
s_PXENV_TFTP_READ_FILE::BufferSize	Length of downloaded file

Downloads an entire file via either TFTP or MTFTP into the buffer pointed to by s_PXENV_TFTP_READ_FILE::Buffer.

The PXE specification does not make it clear how the caller requests that MTFTP be used rather than TFTP (or vice versa). One reasonable guess is that setting s_PXENV_TFTP_READ_FILE::McastIPAddress to 0.0.0.0 would cause TFTP to be used instead of MTFTP, though it is conceivable that some PXE stacks would interpret that as "use the DHCP-provided multicast IP address" instead. Some PXE stacks will not implement MTFTP at all, and will always use TFTP.

It is not specified whether or not s_PXENV_TFTP_READ_FILE::TFTPSrvPort will be used as the TFTP server port for TFTP (rather than MTFTP) downloads. Callers should assume that the only way to access a TFTP server on a non-standard port is to use pxenv_tftp_open() and pxenv_tftp_read().

If s_PXENV_TFTP_READ_FILE::GatewayIPAddress is 0.0.0.0, normal IP routing will take place. See the relevant implementation note for more details.

It is interesting to note that s_PXENV_TFTP_READ_FILE::Buffer is an ADDR32_t type, i.e. nominally a flat physical address. Some PXE NBPs (e.g. NTLDR) are known to call pxenv_tftp_read_file() in real mode with s_PXENV_TFTP_READ_FILE::Buffer set to an address above 1MB. This means that PXE stacks must be prepared to write to areas outside base memory. Exactly how this is to be achieved is not specified, though using INT 15,87 is as close to a standard method as any, and should probably be used. Switching to protected-mode in order to access high memory will fail if pxenv_tftp_read_file() is called in V86 mode; it is reasonably to expect that a V86 monitor would intercept the relatively well-defined INT 15,87 if it wants the PXE stack to be able to write to high memory.

Things get even more interesting if pxenv_tftp_read_file() is called in protected mode, because there is then absolutely no way for the PXE stack to write to an absolute physical address. You can't even get around the problem by creating a special "access everything" segment in the s_PXE data structure, because the #SEGDESC_t descriptors are limited to 64kB in size.

Previous versions of the PXE specification (e.g. WfM 1.1a) provide a separate API call, pxenv_tftp_read_file_pmode(), specifically to work around this problem. The s_PXENV_TFTP_READ_FILE_PMODE parameter block splits s_PXENV_TFTP_READ_FILE::Buffer into s_PXENV_TFTP_READ_FILE_PMODE::BufferSelector and s_PXENV_TFTP_READ_FILE_PMODE::BufferOffset, i.e. it provides a protected-mode segment:offset address for the data buffer. This API call is no longer present in version 2.1 of the PXE specification.

Etherboot makes the assumption that s_PXENV_TFTP_READ_FILE::Buffer is an offset relative to the caller's data segment, when pxenv_tftp_read_file() is called in protected mode.

On x86, you must set the s_PXE::StatusCallout field to a nonzero value before calling this function in protected mode. You cannot call this function with a 32-bit stack segment. (See the relevant implementation note for more details.)

Definition at line 480 of file pxe_tftp.c.

                                                      {
        int rc;

        DBG ( "PXENV_TFTP_READ_FILE to %08x+%x", tftp_read_file->Buffer,
              tftp_read_file->BufferSize );

        /* Open TFTP file */
        if ( ( rc = pxe_tftp_open ( tftp_read_file->ServerIPAddress, 0,
                                    tftp_read_file->FileName, 0 ) ) != 0 ) {
                tftp_read_file->Status = PXENV_STATUS ( rc );
                return PXENV_EXIT_FAILURE;
        }

        /* Read entire file */
        pxe_tftp.buffer = phys_to_user ( tftp_read_file->Buffer );
        pxe_tftp.size = tftp_read_file->BufferSize;
        while ( ( rc = pxe_tftp.rc ) == -EINPROGRESS )
                step();
        pxe_tftp.buffer = UNULL;
        tftp_read_file->BufferSize = pxe_tftp.max_offset;

        /* Close TFTP file */
        pxe_tftp_close ( &pxe_tftp, rc );

        tftp_read_file->Status = PXENV_STATUS ( rc );
        return ( rc ? PXENV_EXIT_FAILURE : PXENV_EXIT_SUCCESS );
}

References pxe_tftp_connection::buffer, s_PXENV_TFTP_READ_FILE::Buffer, s_PXENV_TFTP_READ_FILE::BufferSize, DBG, EINPROGRESS, s_PXENV_TFTP_READ_FILE::FileName, pxe_tftp_connection::max_offset, phys_to_user(), pxe_tftp, pxe_tftp_close(), pxe_tftp_open(), PXENV_EXIT_FAILURE, PXENV_EXIT_SUCCESS, PXENV_STATUS, pxe_tftp_connection::rc, rc, s_PXENV_TFTP_READ_FILE::ServerIPAddress, pxe_tftp_connection::size, s_PXENV_TFTP_READ_FILE::Status, step(), and UNULL.

Referenced by pxenv_restart_tftp().

pxenv_tftp_get_fsize()

static PXENV_EXIT_t pxenv_tftp_get_fsize ( struct s_PXENV_TFTP_GET_FSIZE *  tftp_get_fsize )

static

TFTP GET FILE SIZE.

Parameters

tftp_get_fsize	Pointer to a struct s_PXENV_TFTP_GET_FSIZE
s_PXENV_TFTP_GET_FSIZE::ServerIPAddress	TFTP server IP address
s_PXENV_TFTP_GET_FSIZE::GatewayIPAddress	Relay agent IP address
s_PXENV_TFTP_GET_FSIZE::FileName	File name

Return values

PXENV_EXIT_SUCCESS	File size was determined successfully
PXENV_EXIT_FAILURE	File size was not determined
s_PXENV_TFTP_GET_FSIZE::Status	PXE status code
s_PXENV_TFTP_GET_FSIZE::FileSize	File size

Determine the size of a file on a TFTP server. This uses the "tsize" TFTP option, and so will not work with a TFTP server that does not support TFTP options, or that does not support the "tsize" option.

The PXE specification states that this API call will not open a TFTP connection for subsequent use with pxenv_tftp_read(). (This is somewhat daft, since the only way to obtain the file size via the "tsize" option involves issuing a TFTP open request, but that's life.)

You cannot call pxenv_tftp_get_fsize() while a TFTP or UDP connection is open.

If s_PXENV_TFTP_GET_FSIZE::GatewayIPAddress is 0.0.0.0, normal IP routing will take place. See the relevant implementation note for more details.

On x86, you must set the s_PXE::StatusCallout field to a nonzero value before calling this function in protected mode. You cannot call this function with a 32-bit stack segment. (See the relevant implementation note for more details.)

Note

There is no way to specify the TFTP server port with this API call. Though you can open a file using a non-standard TFTP server port (via s_PXENV_TFTP_OPEN::TFTPPort or, potentially, s_PXENV_TFTP_READ_FILE::TFTPSrvPort), you can only get the size of a file from a TFTP server listening on the standard TFTP port. "Consistency" is not a word in Intel's vocabulary.

Definition at line 551 of file pxe_tftp.c.

                                                             {
        int rc;

        DBG ( "PXENV_TFTP_GET_FSIZE" );

        /* Open TFTP file */
        if ( ( rc = pxe_tftp_open ( tftp_get_fsize->ServerIPAddress, 0,
                                    tftp_get_fsize->FileName, 0 ) ) != 0 ) {
                tftp_get_fsize->Status = PXENV_STATUS ( rc );
                return PXENV_EXIT_FAILURE;
        }

        /* Wait for initial seek to arrive, and record size */
        while ( ( ( rc = pxe_tftp.rc ) == -EINPROGRESS ) &&
                ( pxe_tftp.max_offset == 0 ) ) {
                step();
        }
        tftp_get_fsize->FileSize = pxe_tftp.max_offset;
        DBG ( " fsize=%d", tftp_get_fsize->FileSize );

        /* EINPROGRESS is normal; we don't wait for the whole transfer */
        if ( rc == -EINPROGRESS )
                rc = 0;

        /* Close TFTP file */
        pxe_tftp_close ( &pxe_tftp, rc );

        tftp_get_fsize->Status = PXENV_STATUS ( rc );
        return ( rc ? PXENV_EXIT_FAILURE : PXENV_EXIT_SUCCESS );
}

References DBG, EINPROGRESS, s_PXENV_TFTP_GET_FSIZE::FileName, s_PXENV_TFTP_GET_FSIZE::FileSize, pxe_tftp_connection::max_offset, pxe_tftp, pxe_tftp_close(), pxe_tftp_open(), PXENV_EXIT_FAILURE, PXENV_EXIT_SUCCESS, PXENV_STATUS, pxe_tftp_connection::rc, rc, s_PXENV_TFTP_GET_FSIZE::ServerIPAddress, s_PXENV_TFTP_GET_FSIZE::Status, and step().

Variable Documentation

pxe_tftp_xfer_ops

struct interface_operation pxe_tftp_xfer_ops[]

static

Initial value:

= {
        INTF_OP ( xfer_deliver, struct pxe_tftp_connection *,
                  pxe_tftp_xfer_deliver ),
        INTF_OP ( xfer_window, struct pxe_tftp_connection *,
                  pxe_tftp_xfer_window ),
        INTF_OP ( intf_close, struct pxe_tftp_connection *, pxe_tftp_close ),
}

PXE TFTP connection interface operations.

Definition at line 145 of file pxe_tftp.c.

pxe_tftp_xfer_desc

struct interface_descriptor pxe_tftp_xfer_desc

static

Initial value:

=
        INTF_DESC ( struct pxe_tftp_connection, xfer, pxe_tftp_xfer_ops )

PXE TFTP connection interface descriptor.

Definition at line 154 of file pxe_tftp.c.

Referenced by pxe_tftp_open().

pxe_tftp

struct pxe_tftp_connection pxe_tftp

static

Initial value:

= {
        .xfer = INTF_INIT ( pxe_tftp_xfer_desc ),
}

The PXE TFTP connection.

Definition at line 158 of file pxe_tftp.c.

Referenced by pxe_tftp_close(), pxe_tftp_open(), pxe_tftp_xfer_deliver(), pxe_tftp_xfer_window(), pxenv_tftp_close(), pxenv_tftp_get_fsize(), pxenv_tftp_open(), pxenv_tftp_read(), and pxenv_tftp_read_file().

__pxe_api_call

struct pxe_api_call pxe_tftp_api [] __pxe_api_call

Initial value:

= {
        PXE_API_CALL ( PXENV_TFTP_OPEN, pxenv_tftp_open,
                       struct s_PXENV_TFTP_OPEN ),
        PXE_API_CALL ( PXENV_TFTP_CLOSE, pxenv_tftp_close,
                       struct s_PXENV_TFTP_CLOSE ),
        PXE_API_CALL ( PXENV_TFTP_READ, pxenv_tftp_read,
                       struct s_PXENV_TFTP_READ ),
        PXE_API_CALL ( PXENV_TFTP_READ_FILE, pxenv_tftp_read_file,
                       struct s_PXENV_TFTP_READ_FILE ),
        PXE_API_CALL ( PXENV_TFTP_GET_FSIZE, pxenv_tftp_get_fsize,
                       struct s_PXENV_TFTP_GET_FSIZE ),
}

PXE TFTP API.

Definition at line 584 of file pxe_tftp.c.