#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <vsprintf.h>
#include <assert.h>
#include <errno.h>
#include <gpxe/async.h>
#include <gpxe/ftp.h>
/** @file
*
* File transfer protocol
*
*/
/*****************************************************************************
*
* FTP control channel
*
*/
/** An FTP control channel string */
struct ftp_string {
/** String format */
const char *format;
/** Offset to string data
*
* This is the offset within the struct ftp_request to the
* pointer to the string data. Use ftp_string_data() to get a
* pointer to the actual data.
*/
off_t data_offset;
};
/** FTP control channel strings */
static const struct ftp_string ftp_strings[] = {
[FTP_CONNECT] = { "", 0 },
[FTP_USER] = { "USER anonymous\r\n", 0 },
[FTP_PASS] = { "PASS etherboot@etherboot.org\r\n", 0 },
[FTP_TYPE] = { "TYPE I\r\n", 0 },
[FTP_PASV] = { "PASV\r\n", 0 },
[FTP_RETR] = { "RETR %s\r\n",
offsetof ( struct ftp_request, filename ) },
[FTP_QUIT] = { "QUIT\r\n", 0 },
[FTP_DONE] = { "", 0 },
};
/**
* Get data associated with an FTP control channel string
*
* @v ftp FTP request
* @v data_offset Data offset field from ftp_string structure
* @ret data Pointer to data
*/
static inline const void * ftp_string_data ( struct ftp_request *ftp,
off_t data_offset ) {
return * ( ( void ** ) ( ( ( void * ) ftp ) + data_offset ) );
}
/**
* Get FTP request from control TCP connection
*
* @v conn TCP connection
* @ret ftp FTP request
*/
static inline struct ftp_request * tcp_to_ftp ( struct tcp_connection *conn ) {
return container_of ( conn, struct ftp_request, tcp );
}
static void ftp_set_status ( struct ftp_request *ftp, int rc ) {
if ( ! ftp->rc )
ftp->rc = rc;
}
static void ftp_clear_status ( struct ftp_request *ftp ) {
ftp->rc = 0;
}
/**
* Mark FTP operation as complete
*
* @v ftp FTP request
*/
static void ftp_done ( struct ftp_request *ftp ) {
async_done ( &ftp->aop, ftp->rc );
}
/**
* Parse FTP byte sequence value
*
* @v text Text string
* @v value Value buffer
* @v len Length of value buffer
*
* This parses an FTP byte sequence value (e.g. the "aaa,bbb,ccc,ddd"
* form for IP addresses in PORT commands) into a byte sequence. @c
* *text will be updated to point beyond the end of the parsed byte
* sequence.
*
* This function is safe in the presence of malformed data, though the
* output is undefined.
*/
static void ftp_parse_value ( char **text, uint8_t *value, size_t len ) {
do {
*(value++) = strtoul ( *text, text, 10 );
if ( **text )
(*text)++;
} while ( --len );
}
/**
* Handle an FTP control channel response
*
* @v ftp FTP request
*
* This is called once we have received a complete repsonse line.
*/
static void ftp_reply ( struct ftp_request *ftp ) {
char status_major = ftp->status_text[0];
/* Ignore "intermediate" responses (1xx codes) */
if ( status_major == '1' )
return;
/* Anything other than success (2xx) or, in the case of a
* repsonse to a "USER" command, a password prompt (3xx), is a
* fatal error.
*/
if ( ! ( ( status_major == '2' ) ||
( ( status_major == '3' ) && ( ftp->state == FTP_USER ) ) ) )
goto err;
/* Open passive connection when we get "PASV" response */
if ( ftp->state == FTP_PASV ) {
char *ptr = ftp->passive_text;
struct sockaddr_in *sin =
( struct sockaddr_in * ) &ftp->tcp_data.peer;
sin->sin_family = AF_INET;
ftp_parse_value ( &ptr, ( uint8_t * ) &sin->sin_addr,
sizeof ( sin->sin_addr ) );
ftp_parse_value ( &ptr, ( uint8_t * ) &sin->sin_port,
sizeof ( sin->sin_port ) );
tcp_connect ( &ftp->tcp_data );
}
/* Move to next state */
if ( ftp->state < FTP_DONE )
ftp->state++;
ftp->already_sent = 0;
return;
err:
/* Flag protocol error and close connections */
ftp_set_status ( ftp, -EPROTO );
tcp_close ( &ftp->tcp );
}
/**
* Handle new data arriving on FTP control channel
*
* @v conn TCP connection
* @v data New data
* @v len Length of new data
*
* Data is collected until a complete line is received, at which point
* its information is passed to ftp_reply().
*/
static void ftp_newdata ( struct tcp_connection *conn,
void *data, size_t len ) {
struct ftp_request *ftp = tcp_to_ftp ( conn );
char *recvbuf = ftp->recvbuf;
size_t recvsize = ftp->recvsize;
char c;
while ( len-- ) {
c = * ( ( char * ) data++ );
switch ( c ) {
case '\r' :
case '\n' :
/* End of line: call ftp_reply() to handle
* completed reply. Avoid calling ftp_reply()
* twice if we receive both \r and \n.
*/
if ( recvsize == 0 )
ftp_reply ( ftp );
/* Start filling up the status code buffer */
recvbuf = ftp->status_text;
recvsize = sizeof ( ftp->status_text ) - 1;
break;
case '(' :
/* Start filling up the passive parameter buffer */
recvbuf = ftp->passive_text;
recvsize = sizeof ( ftp->passive_text ) - 1;
break;
case ')' :
/* Stop filling the passive parameter buffer */
recvsize = 0;
break;
default :
/* Fill up buffer if applicable */
if ( recvsize > 0 ) {
*(recvbuf++) = c;
recvsize--;
}
break;
}
}
/* Store for next invocation */
ftp->recvbuf = recvbuf;
ftp->recvsize = recvsize;
}
/**
* Handle acknowledgement of data sent on FTP control channel
*
* @v conn TCP connection
*/
static void ftp_acked ( struct tcp_connection *conn, size_t len ) {
struct ftp_request *ftp = tcp_to_ftp ( conn );
/* Mark off ACKed portion of the currently-transmitted data */
ftp->already_sent += len;
}
/**
* Construct data to send on FTP control channel
*
* @v conn TCP connection
* @v buf Temporary data buffer
* @v len Length of temporary data buffer
*/
static void ftp_senddata ( struct tcp_connection *conn,
void *buf, size_t len ) {
struct ftp_request *ftp = tcp_to_ftp ( conn );
const struct ftp_string *string;
/* Send the as-yet-unACKed portion of the string for the
* current state.
*/
string = &ftp_strings[ftp->state];
len = snprintf ( buf, len, string->format,
ftp_string_data ( ftp, string->data_offset ) );
tcp_send ( conn, buf + ftp->already_sent, len - ftp->already_sent );
}
/**
* Handle control channel being closed
*
* @v conn TCP connection
*
* When the control channel is closed, the data channel must also be
* closed, if it is currently open.
*/
static void ftp_closed ( struct tcp_connection *conn, int status ) {
struct ftp_request *ftp = tcp_to_ftp ( conn );
/* Close data channel and record status */
ftp_set_status ( ftp, status );
tcp_close ( &ftp->tcp_data );
/* Mark FTP operation as complete if we are the last
* connection to close
*/
if ( tcp_closed ( &ftp->tcp_data ) )
ftp_done ( ftp );
}
/** FTP control channel operations */
static struct tcp_operations ftp_tcp_operations = {
.closed = ftp_closed,
.acked = ftp_acked,
.newdata = ftp_newdata,
.senddata = ftp_senddata,
};
/*****************************************************************************
*
* FTP data channel
*
*/
/**
* Get FTP request from data TCP connection
*
* @v conn TCP connection
* @ret ftp FTP request
*/
static inline struct ftp_request *
tcp_to_ftp_data ( struct tcp_connection *conn ) {
return container_of ( conn, struct ftp_request, tcp_data );
}
/**
* Handle data channel being closed
*
* @v conn TCP connection
*
* When the data channel is closed, the control channel should be left
* alone; the server will send a completion message via the control
* channel which we'll pick up.
*
* If the data channel is closed due to an error, we abort the request.
*/
static void ftp_data_closed ( struct tcp_connection *conn, int status ) {
struct ftp_request *ftp = tcp_to_ftp_data ( conn );
/* If there was an error, close control channel and record status */
if ( status ) {
ftp_set_status ( ftp, status );
tcp_close ( &ftp->tcp );
}
/* Mark FTP operation as complete if we are the last
* connection to close
*/
if ( tcp_closed ( &ftp->tcp ) )
ftp_done ( ftp );
}
/**
* Handle new data arriving on the FTP data channel
*
* @v conn TCP connection
* @v data New data
* @v len Length of new data
*
* Data is handed off to the callback registered in the FTP request.
*/
static void ftp_data_newdata ( struct tcp_connection *conn,
void *data, size_t len ) {
struct ftp_request *ftp = tcp_to_ftp_data ( conn );
ftp->callback ( data, len );
}
/** FTP data channel operations */
static struct tcp_operations ftp_data_tcp_operations = {
.closed = ftp_data_closed,
.newdata = ftp_data_newdata,
};
/*****************************************************************************
*
* API
*
*/
/**
* Initiate an FTP connection
*
* @v ftp FTP request
*/
struct async_operation * ftp_get ( struct ftp_request *ftp ) {
ftp->tcp.tcp_op = &ftp_tcp_operations;
ftp->tcp_data.tcp_op = &ftp_data_tcp_operations;
ftp->recvbuf = ftp->status_text;
ftp->recvsize = sizeof ( ftp->status_text ) - 1;
ftp_clear_status ( ftp );
tcp_connect ( &ftp->tcp );
return &ftp->aop;
}
