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      1 /** @file
      2  *
      3  * PXE UDP API
      4  *
      5  */
      6 
      7 #include <string.h>
      8 #include <byteswap.h>
      9 #include <gpxe/xfer.h>
     10 #include <gpxe/udp.h>
     11 #include <gpxe/uaccess.h>
     12 #include <gpxe/process.h>
     13 #include <pxe.h>
     14 
     15 /*
     16  * Copyright (C) 2004 Michael Brown <mbrown (at) fensystems.co.uk>.
     17  *
     18  * This program is free software; you can redistribute it and/or
     19  * modify it under the terms of the GNU General Public License as
     20  * published by the Free Software Foundation; either version 2 of the
     21  * License, or any later version.
     22  *
     23  * This program is distributed in the hope that it will be useful, but
     24  * WITHOUT ANY WARRANTY; without even the implied warranty of
     25  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     26  * General Public License for more details.
     27  *
     28  * You should have received a copy of the GNU General Public License
     29  * along with this program; if not, write to the Free Software
     30  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
     31  */
     32 
     33 FILE_LICENCE ( GPL2_OR_LATER );
     34 
     35 /** A PXE UDP connection */
     36 struct pxe_udp_connection {
     37 	/** Data transfer interface to UDP stack */
     38 	struct xfer_interface xfer;
     39 	/** Local address */
     40 	struct sockaddr_in local;
     41 	/** Current PXENV_UDP_READ parameter block */
     42 	struct s_PXENV_UDP_READ *pxenv_udp_read;
     43 };
     44 
     45 /**
     46  * Receive PXE UDP data
     47  *
     48  * @v xfer			Data transfer interface
     49  * @v iobuf			I/O buffer
     50  * @v meta			Data transfer metadata
     51  * @ret rc			Return status code
     52  *
     53  * Receives a packet as part of the current pxenv_udp_read()
     54  * operation.
     55  */
     56 static int pxe_udp_deliver_iob ( struct xfer_interface *xfer,
     57 				 struct io_buffer *iobuf,
     58 				 struct xfer_metadata *meta ) {
     59 	struct pxe_udp_connection *pxe_udp =
     60 		container_of ( xfer, struct pxe_udp_connection, xfer );
     61 	struct s_PXENV_UDP_READ *pxenv_udp_read = pxe_udp->pxenv_udp_read;
     62 	struct sockaddr_in *sin_src;
     63 	struct sockaddr_in *sin_dest;
     64 	userptr_t buffer;
     65 	size_t len;
     66 	int rc = 0;
     67 
     68 	if ( ! pxenv_udp_read ) {
     69 		DBG ( "PXE discarded UDP packet\n" );
     70 		rc = -ENOBUFS;
     71 		goto done;
     72 	}
     73 
     74 	/* Copy packet to buffer and record length */
     75 	buffer = real_to_user ( pxenv_udp_read->buffer.segment,
     76 				pxenv_udp_read->buffer.offset );
     77 	len = iob_len ( iobuf );
     78 	if ( len > pxenv_udp_read->buffer_size )
     79 		len = pxenv_udp_read->buffer_size;
     80 	copy_to_user ( buffer, 0, iobuf->data, len );
     81 	pxenv_udp_read->buffer_size = len;
     82 
     83 	/* Fill in source/dest information */
     84 	assert ( meta );
     85 	sin_src = ( struct sockaddr_in * ) meta->src;
     86 	assert ( sin_src );
     87 	assert ( sin_src->sin_family == AF_INET );
     88 	pxenv_udp_read->src_ip = sin_src->sin_addr.s_addr;
     89 	pxenv_udp_read->s_port = sin_src->sin_port;
     90 	sin_dest = ( struct sockaddr_in * ) meta->dest;
     91 	assert ( sin_dest );
     92 	assert ( sin_dest->sin_family == AF_INET );
     93 	pxenv_udp_read->dest_ip = sin_dest->sin_addr.s_addr;
     94 	pxenv_udp_read->d_port = sin_dest->sin_port;
     95 
     96 	/* Mark as received */
     97 	pxe_udp->pxenv_udp_read = NULL;
     98 
     99  done:
    100 	free_iob ( iobuf );
    101 	return rc;
    102 }
    103 
    104 /** PXE UDP data transfer interface operations */
    105 static struct xfer_interface_operations pxe_udp_xfer_operations = {
    106 	.close		= ignore_xfer_close,
    107 	.vredirect	= ignore_xfer_vredirect,
    108 	.window		= unlimited_xfer_window,
    109 	.alloc_iob	= default_xfer_alloc_iob,
    110 	.deliver_iob	= pxe_udp_deliver_iob,
    111 	.deliver_raw	= xfer_deliver_as_iob,
    112 };
    113 
    114 /** The PXE UDP connection */
    115 static struct pxe_udp_connection pxe_udp = {
    116 	.xfer = XFER_INIT ( &pxe_udp_xfer_operations ),
    117 	.local = {
    118 		.sin_family = AF_INET,
    119 	},
    120 };
    121 
    122 /**
    123  * UDP OPEN
    124  *
    125  * @v pxenv_udp_open			Pointer to a struct s_PXENV_UDP_OPEN
    126  * @v s_PXENV_UDP_OPEN::src_ip		IP address of this station, or 0.0.0.0
    127  * @ret #PXENV_EXIT_SUCCESS		Always
    128  * @ret s_PXENV_UDP_OPEN::Status	PXE status code
    129  * @err #PXENV_STATUS_UDP_OPEN		UDP connection already open
    130  * @err #PXENV_STATUS_OUT_OF_RESOURCES	Could not open connection
    131  *
    132  * Prepares the PXE stack for communication using pxenv_udp_write()
    133  * and pxenv_udp_read().
    134  *
    135  * The IP address supplied in s_PXENV_UDP_OPEN::src_ip will be
    136  * recorded and used as the local station's IP address for all further
    137  * communication, including communication by means other than
    138  * pxenv_udp_write() and pxenv_udp_read().  (If
    139  * s_PXENV_UDP_OPEN::src_ip is 0.0.0.0, the local station's IP address
    140  * will remain unchanged.)
    141  *
    142  * You can only have one open UDP connection at a time.  This is not a
    143  * meaningful restriction, since pxenv_udp_write() and
    144  * pxenv_udp_read() allow you to specify arbitrary local and remote
    145  * ports and an arbitrary remote address for each packet.  According
    146  * to the PXE specifiation, you cannot have a UDP connection open at
    147  * the same time as a TFTP connection; this restriction does not apply
    148  * to Etherboot.
    149  *
    150  * On x86, you must set the s_PXE::StatusCallout field to a nonzero
    151  * value before calling this function in protected mode.  You cannot
    152  * call this function with a 32-bit stack segment.  (See the relevant
    153  * @ref pxe_x86_pmode16 "implementation note" for more details.)
    154  *
    155  * @note The PXE specification does not make it clear whether the IP
    156  * address supplied in s_PXENV_UDP_OPEN::src_ip should be used only
    157  * for this UDP connection, or retained for all future communication.
    158  * The latter seems more consistent with typical PXE stack behaviour.
    159  *
    160  * @note Etherboot currently ignores the s_PXENV_UDP_OPEN::src_ip
    161  * parameter.
    162  *
    163  */
    164 PXENV_EXIT_t pxenv_udp_open ( struct s_PXENV_UDP_OPEN *pxenv_udp_open ) {
    165 	int rc;
    166 
    167 	DBG ( "PXENV_UDP_OPEN" );
    168 
    169 	/* Record source IP address */
    170 	pxe_udp.local.sin_addr.s_addr = pxenv_udp_open->src_ip;
    171 	DBG ( " %s", inet_ntoa ( pxe_udp.local.sin_addr ) );
    172 
    173 	/* Open promiscuous UDP connection */
    174 	xfer_close ( &pxe_udp.xfer, 0 );
    175 	if ( ( rc = udp_open_promisc ( &pxe_udp.xfer ) ) != 0 ) {
    176 		pxenv_udp_open->Status = PXENV_STATUS ( rc );
    177 		return PXENV_EXIT_FAILURE;
    178 	}
    179 
    180 	pxenv_udp_open->Status = PXENV_STATUS_SUCCESS;
    181 	return PXENV_EXIT_SUCCESS;
    182 }
    183 
    184 /**
    185  * UDP CLOSE
    186  *
    187  * @v pxenv_udp_close			Pointer to a struct s_PXENV_UDP_CLOSE
    188  * @ret #PXENV_EXIT_SUCCESS		Always
    189  * @ret s_PXENV_UDP_CLOSE::Status	PXE status code
    190  * @err None				-
    191  *
    192  * Closes a UDP connection opened with pxenv_udp_open().
    193  *
    194  * You can only have one open UDP connection at a time.  You cannot
    195  * have a UDP connection open at the same time as a TFTP connection.
    196  * You cannot use pxenv_udp_close() to close a TFTP connection; use
    197  * pxenv_tftp_close() instead.
    198  *
    199  * On x86, you must set the s_PXE::StatusCallout field to a nonzero
    200  * value before calling this function in protected mode.  You cannot
    201  * call this function with a 32-bit stack segment.  (See the relevant
    202  * @ref pxe_x86_pmode16 "implementation note" for more details.)
    203  *
    204  */
    205 PXENV_EXIT_t pxenv_udp_close ( struct s_PXENV_UDP_CLOSE *pxenv_udp_close ) {
    206 	DBG ( "PXENV_UDP_CLOSE" );
    207 
    208 	/* Close UDP connection */
    209 	xfer_close ( &pxe_udp.xfer, 0 );
    210 
    211 	pxenv_udp_close->Status = PXENV_STATUS_SUCCESS;
    212 	return PXENV_EXIT_SUCCESS;
    213 }
    214 
    215 /**
    216  * UDP WRITE
    217  *
    218  * @v pxenv_udp_write			Pointer to a struct s_PXENV_UDP_WRITE
    219  * @v s_PXENV_UDP_WRITE::ip		Destination IP address
    220  * @v s_PXENV_UDP_WRITE::gw		Relay agent IP address, or 0.0.0.0
    221  * @v s_PXENV_UDP_WRITE::src_port	Source UDP port, or 0
    222  * @v s_PXENV_UDP_WRITE::dst_port	Destination UDP port
    223  * @v s_PXENV_UDP_WRITE::buffer_size	Length of the UDP payload
    224  * @v s_PXENV_UDP_WRITE::buffer		Address of the UDP payload
    225  * @ret #PXENV_EXIT_SUCCESS		Packet was transmitted successfully
    226  * @ret #PXENV_EXIT_FAILURE		Packet could not be transmitted
    227  * @ret s_PXENV_UDP_WRITE::Status	PXE status code
    228  * @err #PXENV_STATUS_UDP_CLOSED	UDP connection is not open
    229  * @err #PXENV_STATUS_UNDI_TRANSMIT_ERROR Could not transmit packet
    230  *
    231  * Transmits a single UDP packet.  A valid IP and UDP header will be
    232  * prepended to the payload in s_PXENV_UDP_WRITE::buffer; the buffer
    233  * should not contain precomputed IP and UDP headers, nor should it
    234  * contain space allocated for these headers.  The first byte of the
    235  * buffer will be transmitted as the first byte following the UDP
    236  * header.
    237  *
    238  * If s_PXENV_UDP_WRITE::gw is 0.0.0.0, normal IP routing will take
    239  * place.  See the relevant @ref pxe_routing "implementation note" for
    240  * more details.
    241  *
    242  * If s_PXENV_UDP_WRITE::src_port is 0, port 2069 will be used.
    243  *
    244  * You must have opened a UDP connection with pxenv_udp_open() before
    245  * calling pxenv_udp_write().
    246  *
    247  * On x86, you must set the s_PXE::StatusCallout field to a nonzero
    248  * value before calling this function in protected mode.  You cannot
    249  * call this function with a 32-bit stack segment.  (See the relevant
    250  * @ref pxe_x86_pmode16 "implementation note" for more details.)
    251  *
    252  * @note Etherboot currently ignores the s_PXENV_UDP_WRITE::gw
    253  * parameter.
    254  *
    255  */
    256 PXENV_EXIT_t pxenv_udp_write ( struct s_PXENV_UDP_WRITE *pxenv_udp_write ) {
    257 	struct sockaddr_in dest;
    258 	struct xfer_metadata meta = {
    259 		.src = ( struct sockaddr * ) &pxe_udp.local,
    260 		.dest = ( struct sockaddr * ) &dest,
    261 		.netdev = pxe_netdev,
    262 	};
    263 	size_t len;
    264 	struct io_buffer *iobuf;
    265 	userptr_t buffer;
    266 	int rc;
    267 
    268 	DBG ( "PXENV_UDP_WRITE" );
    269 
    270 	/* Construct destination socket address */
    271 	memset ( &dest, 0, sizeof ( dest ) );
    272 	dest.sin_family = AF_INET;
    273 	dest.sin_addr.s_addr = pxenv_udp_write->ip;
    274 	dest.sin_port = pxenv_udp_write->dst_port;
    275 
    276 	/* Set local (source) port.  PXE spec says source port is 2069
    277 	 * if not specified.  Really, this ought to be set at UDP open
    278 	 * time but hey, we didn't design this API.
    279 	 */
    280 	pxe_udp.local.sin_port = pxenv_udp_write->src_port;
    281 	if ( ! pxe_udp.local.sin_port )
    282 		pxe_udp.local.sin_port = htons ( 2069 );
    283 
    284 	/* FIXME: we ignore the gateway specified, since we're
    285 	 * confident of being able to do our own routing.  We should
    286 	 * probably allow for multiple gateways.
    287 	 */
    288 
    289 	/* Allocate and fill data buffer */
    290 	len = pxenv_udp_write->buffer_size;
    291 	iobuf = xfer_alloc_iob ( &pxe_udp.xfer, len );
    292 	if ( ! iobuf ) {
    293 		pxenv_udp_write->Status = PXENV_STATUS_OUT_OF_RESOURCES;
    294 		return PXENV_EXIT_FAILURE;
    295 	}
    296 	buffer = real_to_user ( pxenv_udp_write->buffer.segment,
    297 				pxenv_udp_write->buffer.offset );
    298 	copy_from_user ( iob_put ( iobuf, len ), buffer, 0, len );
    299 
    300 	DBG ( " %04x:%04x+%x %d->%s:%d", pxenv_udp_write->buffer.segment,
    301 	      pxenv_udp_write->buffer.offset, pxenv_udp_write->buffer_size,
    302 	      ntohs ( pxenv_udp_write->src_port ),
    303 	      inet_ntoa ( dest.sin_addr ),
    304 	      ntohs ( pxenv_udp_write->dst_port ) );
    305 
    306 	/* Transmit packet */
    307 	if ( ( rc = xfer_deliver_iob_meta ( &pxe_udp.xfer, iobuf,
    308 					    &meta ) ) != 0 ) {
    309 		pxenv_udp_write->Status = PXENV_STATUS ( rc );
    310 		return PXENV_EXIT_FAILURE;
    311 	}
    312 
    313 	pxenv_udp_write->Status = PXENV_STATUS_SUCCESS;
    314 	return PXENV_EXIT_SUCCESS;
    315 }
    316 
    317 /**
    318  * UDP READ
    319  *
    320  * @v pxenv_udp_read			Pointer to a struct s_PXENV_UDP_READ
    321  * @v s_PXENV_UDP_READ::dest_ip		Destination IP address, or 0.0.0.0
    322  * @v s_PXENV_UDP_READ::d_port		Destination UDP port, or 0
    323  * @v s_PXENV_UDP_READ::buffer_size	Size of the UDP payload buffer
    324  * @v s_PXENV_UDP_READ::buffer		Address of the UDP payload buffer
    325  * @ret #PXENV_EXIT_SUCCESS		A packet has been received
    326  * @ret #PXENV_EXIT_FAILURE		No packet has been received
    327  * @ret s_PXENV_UDP_READ::Status	PXE status code
    328  * @ret s_PXENV_UDP_READ::src_ip	Source IP address
    329  * @ret s_PXENV_UDP_READ::dest_ip	Destination IP address
    330  * @ret s_PXENV_UDP_READ::s_port	Source UDP port
    331  * @ret s_PXENV_UDP_READ::d_port	Destination UDP port
    332  * @ret s_PXENV_UDP_READ::buffer_size	Length of UDP payload
    333  * @err #PXENV_STATUS_UDP_CLOSED	UDP connection is not open
    334  * @err #PXENV_STATUS_FAILURE		No packet was ready to read
    335  *
    336  * Receive a single UDP packet.  This is a non-blocking call; if no
    337  * packet is ready to read, the call will return instantly with
    338  * s_PXENV_UDP_READ::Status==PXENV_STATUS_FAILURE.
    339  *
    340  * If s_PXENV_UDP_READ::dest_ip is 0.0.0.0, UDP packets addressed to
    341  * any IP address will be accepted and may be returned to the caller.
    342  *
    343  * If s_PXENV_UDP_READ::d_port is 0, UDP packets addressed to any UDP
    344  * port will be accepted and may be returned to the caller.
    345  *
    346  * You must have opened a UDP connection with pxenv_udp_open() before
    347  * calling pxenv_udp_read().
    348  *
    349  * On x86, you must set the s_PXE::StatusCallout field to a nonzero
    350  * value before calling this function in protected mode.  You cannot
    351  * call this function with a 32-bit stack segment.  (See the relevant
    352  * @ref pxe_x86_pmode16 "implementation note" for more details.)
    353  *
    354  * @note The PXE specification (version 2.1) does not state that we
    355  * should fill in s_PXENV_UDP_READ::dest_ip and
    356  * s_PXENV_UDP_READ::d_port, but Microsoft Windows' NTLDR program
    357  * expects us to do so, and will fail if we don't.
    358  *
    359  */
    360 PXENV_EXIT_t pxenv_udp_read ( struct s_PXENV_UDP_READ *pxenv_udp_read ) {
    361 	struct in_addr dest_ip_wanted = { .s_addr = pxenv_udp_read->dest_ip };
    362 	struct in_addr dest_ip;
    363 	uint16_t d_port_wanted = pxenv_udp_read->d_port;
    364 	uint16_t d_port;
    365 
    366 	DBG ( "PXENV_UDP_READ" );
    367 
    368 	/* Try receiving a packet */
    369 	pxe_udp.pxenv_udp_read = pxenv_udp_read;
    370 	step();
    371 	if ( pxe_udp.pxenv_udp_read ) {
    372 		/* No packet received */
    373 		pxe_udp.pxenv_udp_read = NULL;
    374 		goto no_packet;
    375 	}
    376 	dest_ip.s_addr = pxenv_udp_read->dest_ip;
    377 	d_port = pxenv_udp_read->d_port;
    378 
    379 	/* Filter on destination address and/or port */
    380 	if ( dest_ip_wanted.s_addr &&
    381 	     ( dest_ip_wanted.s_addr != dest_ip.s_addr ) ) {
    382 		DBG ( " wrong IP %s", inet_ntoa ( dest_ip ) );
    383 		DBG ( " (wanted %s)", inet_ntoa ( dest_ip_wanted ) );
    384 		goto no_packet;
    385 	}
    386 	if ( d_port_wanted && ( d_port_wanted != d_port ) ) {
    387 		DBG ( " wrong port %d ", htons ( d_port ) );
    388 		DBG ( " (wanted %d)", htons ( d_port_wanted ) );
    389 		goto no_packet;
    390 	}
    391 
    392 	DBG ( " %04x:%04x+%x %s:", pxenv_udp_read->buffer.segment,
    393 	      pxenv_udp_read->buffer.offset, pxenv_udp_read->buffer_size,
    394 	      inet_ntoa ( *( ( struct in_addr * ) &pxenv_udp_read->src_ip ) ));
    395 	DBG ( "%d<-%s:%d",  ntohs ( pxenv_udp_read->s_port ),
    396 	      inet_ntoa ( *( ( struct in_addr * ) &pxenv_udp_read->dest_ip ) ),
    397 	      ntohs ( pxenv_udp_read->d_port ) );
    398 
    399 	pxenv_udp_read->Status = PXENV_STATUS_SUCCESS;
    400 	return PXENV_EXIT_SUCCESS;
    401 
    402  no_packet:
    403 	pxenv_udp_read->Status = PXENV_STATUS_FAILURE;
    404 	return PXENV_EXIT_FAILURE;
    405 }
    406