First version
This commit is contained in:
Michael Brown
parent
5265975334
commit
8ae966720d
|
|
@ -0,0 +1,299 @@
|
|||
#include "tftp.h"
|
||||
#include "tcp.h" /* for struct tcphdr */
|
||||
#include "errno.h"
|
||||
#include "etherboot.h"
|
||||
|
||||
/** @file
|
||||
*
|
||||
* TFTP core functions
|
||||
*
|
||||
* This file provides functions that are common to the TFTP (rfc1350),
|
||||
* TFTM (rfc2090) and MTFTP (PXE) protocols.
|
||||
*
|
||||
*/
|
||||
|
||||
/**
|
||||
* Wait for a TFTP packet
|
||||
*
|
||||
* @v ptr Pointer to a struct tftp_state
|
||||
* @v ip IP header
|
||||
* @v udp UDP header
|
||||
* @ret True This is our TFTP packet
|
||||
* @ret False This is not one of our TFTP packets
|
||||
*
|
||||
* Wait for a TFTP packet that is part of the current connection
|
||||
* (i.e. comes from the TFTP server, has the correct destination port,
|
||||
* and is addressed either to our IP address or to our multicast
|
||||
* listening address).
|
||||
*/
|
||||
static int await_tftp ( int ival __unused, void *ptr,
|
||||
unsigned short ptype __unused, struct iphdr *ip,
|
||||
struct udphdr *udp, struct tcphdr *tcp __unused ) {
|
||||
struct tftp_state *state = ptr;
|
||||
|
||||
/* Must have valid UDP (and, therefore, also IP) headers */
|
||||
if ( ! udp ) {
|
||||
return 0;
|
||||
}
|
||||
/* Packet must come from the TFTP server */
|
||||
if ( ip->src.s_addr != state->server.sin_addr.s_addr )
|
||||
return 0;
|
||||
/* Packet must be addressed to the correct UDP port */
|
||||
if ( ntohs ( udp->dest ) != state->client.sin_port )
|
||||
return 0;
|
||||
/* Packet must be addressed to us, or to our multicast
|
||||
* listening address (if we have one).
|
||||
*/
|
||||
if ( ! ( ( ip->dest.s_addr == arptable[ARP_CLIENT].ipaddr.s_addr ) ||
|
||||
( ( state->client.sin_addr.s_addr ) &&
|
||||
( ip->dest.s_addr == state->client.sin_addr.s_addr ) ) ) )
|
||||
return 0;
|
||||
return 1;
|
||||
}
|
||||
|
||||
|
||||
/**
|
||||
* Issue a TFTP open request (RRQ)
|
||||
*
|
||||
* @v filename File name
|
||||
* @v state TFTP transfer state
|
||||
* @v tftp_state::server::sin_addr TFTP server IP address
|
||||
* @v tftp_state::server::sin_port TFTP server UDP port, or 0
|
||||
* @v tftp_state::client::sin_addr Client multicast IP address, or 0.0.0.0
|
||||
* @v tftp_state::client::sin_port Client UDP port, or 0
|
||||
* @v tftp_state::blksize Requested blksize, or 0
|
||||
* @ret True Received a non-error response
|
||||
* @ret False Received error response / no response
|
||||
* @ret tftp_state::client::sin_port Client UDP port
|
||||
* @ret tftp_state::client::blksize Always #TFTP_DEFAULT_BLKSIZE
|
||||
* @ret *tftp The server's response, if any
|
||||
*
|
||||
* Send a TFTP/TFTM/MTFTP RRQ (read request) to a TFTP server, and
|
||||
* return the server's reply (which may be an OACK, DATA or ERROR
|
||||
* packet). The server's reply will not be acknowledged, or processed
|
||||
* in any way.
|
||||
*
|
||||
* If tftp_state::server::sin_port is 0, the standard tftp server port
|
||||
* (#TFTP_PORT) will be used.
|
||||
*
|
||||
* If tftp_state::client::sin_addr is not 0.0.0.0, it will be used as
|
||||
* a multicast listening address for replies from the TFTP server.
|
||||
*
|
||||
* If tftp_state::client::sin_port is 0, the standard mechanism of
|
||||
* using a new, unique port number for each TFTP request will be used.
|
||||
*
|
||||
* For the various different types of TFTP server, you should treat
|
||||
* tftp_state::client as follows:
|
||||
*
|
||||
* - Standard TFTP server: set tftp_state::client::sin_addr to
|
||||
* 0.0.0.0 and tftp_state::client::sin_port to 0. tftp_open()
|
||||
* will set tftp_state::client::sin_port to the assigned local UDP
|
||||
* port.
|
||||
*
|
||||
* - TFTM server: set tftp_state::client::sin_addr to 0.0.0.0 and
|
||||
* tftp_state::client::sin_port to 0. tftp_open() will set
|
||||
* tftp_state::client::sin_port to the assigned local UDP port.
|
||||
* (Your call to tftp_process_opts() will then overwrite both
|
||||
* tftp_state::client::sin_addr and tftp_state::client::sin_port
|
||||
* with the values return in the OACK packet.)
|
||||
*
|
||||
* - MTFTP server: set tftp_state::client::sin_addr to the client
|
||||
* multicast address and tftp_state::client::sin_port to the
|
||||
* client multicast port (both of which must be previously known,
|
||||
* e.g. provided by a DHCP server). tftp_open() will not alter
|
||||
* these values.
|
||||
*
|
||||
* If tftp_state::blksize is 0, the maximum blocksize
|
||||
* (#TFTP_MAX_BLKSIZE) will be requested.
|
||||
*
|
||||
* On exit, tftp_state::blksize will always contain
|
||||
* #TFTP_DEFAULT_BLKSIZE, since this is the blocksize value that must
|
||||
* be assumed until the OACK packet is processed (by a subsequent call
|
||||
* to tftp_process_opts()).
|
||||
*
|
||||
* The options "blksize", "tsize" and "multicast" will always be
|
||||
* appended to a TFTP open request. Servers that do not understand
|
||||
* any of these options should simply ignore them.
|
||||
*
|
||||
* tftp_open() will not automatically join or leave multicast groups;
|
||||
* the caller is responsible for calling join_group() and
|
||||
* leave_group() at appropriate times.
|
||||
*
|
||||
*/
|
||||
int tftp_open ( const char *filename, struct tftp_state *state,
|
||||
union tftp_any **tftp ) {
|
||||
static unsigned short lport = 2000; /* local port */
|
||||
int fixed_lport;
|
||||
struct tftp_rrq rrq;
|
||||
unsigned int rrqlen;
|
||||
int retry;
|
||||
|
||||
/* Flush receive queue */
|
||||
rx_qdrain();
|
||||
|
||||
/* Default to blksize of TFTP_MAX_BLKSIZE if none specified */
|
||||
if ( ! state->blksize )
|
||||
state->blksize = TFTP_MAX_BLKSIZE;
|
||||
|
||||
/* Use default TFTP server port if none specified */
|
||||
if ( ! state->server.sin_port )
|
||||
state->server.sin_port = TFTP_PORT;
|
||||
|
||||
/* Determine whether or not to use lport */
|
||||
fixed_lport = state->server.sin_port;
|
||||
|
||||
/* Set up RRQ */
|
||||
rrq.opcode = htons ( TFTP_RRQ );
|
||||
rrqlen = ( offsetof ( typeof ( rrq ), data ) +
|
||||
sprintf ( rrq.data,
|
||||
"%s%coctet%cblksize%c%d%ctsize%c0%cmulticast%c",
|
||||
filename, 0, 0, 0, state->blksize, 0, 0, 0, 0 )
|
||||
+ 1 );
|
||||
|
||||
/* Set negotiated blksize to default value */
|
||||
state->blksize = TFTP_DEFAULT_BLKSIZE;
|
||||
|
||||
/* Nullify received packet pointer */
|
||||
*tftp = NULL;
|
||||
|
||||
/* Transmit RRQ until we get a response */
|
||||
for ( retry = 0 ; retry < MAX_TFTP_RETRIES ; retry++ ) {
|
||||
long timeout = rfc2131_sleep_interval ( TIMEOUT, retry );
|
||||
|
||||
/* Set client UDP port, if not already fixed */
|
||||
if ( ! fixed_lport )
|
||||
state->client.sin_port = ++lport;
|
||||
|
||||
/* Send the RRQ */
|
||||
if ( ! udp_transmit ( state->server.sin_addr.s_addr,
|
||||
state->client.sin_port,
|
||||
state->server.sin_port,
|
||||
rrqlen, &rrq ) )
|
||||
return 0;
|
||||
|
||||
/* Wait for response */
|
||||
if ( await_reply ( await_tftp, 0, state, timeout ) ) {
|
||||
*tftp = ( union tftp_any * ) &nic.packet[ETH_HLEN];
|
||||
return 1;
|
||||
}
|
||||
}
|
||||
|
||||
errno = PXENV_STATUS_TFTP_OPEN_TIMEOUT;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* Process a TFTP OACK packet
|
||||
*
|
||||
* @v oack The TFTP OACK packet
|
||||
* @v state TFTP transfer state
|
||||
* @ret True Options were processed successfully
|
||||
* @ret False Options were not processed successfully
|
||||
* @ret tftp_state::blksize Negotiated blksize
|
||||
* @ret tftp_state::tsize File size (if known), or 0
|
||||
* @ret tftp_state::client::sin_addr Client multicast IP address, or 0.0.0.0
|
||||
* @ret tftp_state::client::sin_port Client UDP port
|
||||
* @ret tftp_state::master Client is master
|
||||
* @err EINVAL An invalid option value was encountered
|
||||
*
|
||||
* Process the options returned by the TFTP server in an rfc2347 OACK
|
||||
* packet. The options "blksize" (rfc2348), "tsize" (rfc2349) and
|
||||
* "multicast" (rfc2090) are recognised and processed; any other
|
||||
* options are silently ignored.
|
||||
*
|
||||
* Where an option is not present in the OACK packet, the
|
||||
* corresponding field(s) in #state will be left unaltered.
|
||||
*
|
||||
* Calling tftp_process_opts() does not send an acknowledgement for
|
||||
* the OACK packet; this is the responsibility of the caller.
|
||||
*
|
||||
* @note If the "blksize" option is not present, tftp_state::blksize
|
||||
* will @b not be implicitly set to #TFTP_DEFAULT_BLKSIZE. However,
|
||||
* since tftp_open() always sets tftp_state::blksize to
|
||||
* #TFTP_DEFAULT_BLKSIZE before returning, you probably don't need to
|
||||
* worry about this.
|
||||
*/
|
||||
int tftp_process_opts ( struct tftp_oack *oack, struct tftp_state *state ) {
|
||||
const char *p;
|
||||
const char *end;
|
||||
|
||||
/* End of options */
|
||||
end = ( ( char * ) &oack->udp ) + ntohs ( oack->udp.len );
|
||||
|
||||
/* Only possible error */
|
||||
errno = EINVAL;
|
||||
|
||||
for ( p = oack->data ; p < end ; ) {
|
||||
if ( strcasecmp ( "blksize", p ) == 0 ) {
|
||||
p += 8;
|
||||
state->blksize = strtoul ( p, &p, 10 );
|
||||
if ( *p ) {
|
||||
DBG ( "TFTPCORE: garbage \"%s\" "
|
||||
"after blksize\n", p );
|
||||
return 0;
|
||||
}
|
||||
p++;
|
||||
} else if ( strcasecmp ( "tsize", p ) == 0 ) {
|
||||
p += 6;
|
||||
state->tsize = strtoul ( p, &p, 10 );
|
||||
if ( *p ) {
|
||||
DBG ( "TFTPCORE: garbage \"%s\" "
|
||||
"after tsize\n", p );
|
||||
return 0;
|
||||
}
|
||||
p++;
|
||||
} else if ( strcasecmp ( "multicast", p ) == 0 ) {
|
||||
char *e = strchr ( p, ',' );
|
||||
if ( ( ! e ) || ( e >= end ) ) {
|
||||
DBG ( "TFTPCORE: malformed multicast field "
|
||||
"\"%s\"\n", p );
|
||||
return 0;
|
||||
}
|
||||
/* IP address may be missing, in which case we
|
||||
* should leave state->client.sin_addr
|
||||
* unaltered.
|
||||
*/
|
||||
if ( e != p ) {
|
||||
int rc;
|
||||
*e = '\0';
|
||||
rc = inet_aton ( p, &state->client.sin_addr );
|
||||
*e = ',';
|
||||
if ( ! rc ) {
|
||||
DBG ( "TFTPCORE: malformed multicast "
|
||||
"IP address \"%s\"\n", p );
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
p = e + 1;
|
||||
/* UDP port may also be missing */
|
||||
if ( *p != ',' ) {
|
||||
state->client.sin_port = strtoul ( p, &p, 10 );
|
||||
if ( *p != ',' ) {
|
||||
DBG ( "TFTPCORE: garbage \"%s\" "
|
||||
"after multicast port\n", p );
|
||||
return 0;
|
||||
}
|
||||
} else {
|
||||
p++;
|
||||
}
|
||||
/* "Master Client" must always be present */
|
||||
state->master = strtoul ( p, &p, 10 );
|
||||
if ( *p ) {
|
||||
DBG ( "TFTPCORE: garbage \"%s\" "
|
||||
"after multicast mc\n", p );
|
||||
return 0;
|
||||
}
|
||||
p++;
|
||||
} else {
|
||||
p += strlen ( p ) + 1; /* skip option name */
|
||||
p += strlen ( p ) + 1; /* skip option value */
|
||||
}
|
||||
}
|
||||
|
||||
if ( p > end ) {
|
||||
DBG ( "TFTPCORE: overran options in OACK\n" );
|
||||
return 0;
|
||||
}
|
||||
|
||||
return 1;
|
||||
}
|
||||
Reference in New Issue