/*
* Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <errno.h>
#include <ctype.h>
#include <byteswap.h>
#include <ipxe/socket.h>
#include <ipxe/tcpip.h>
#include <ipxe/in.h>
#include <ipxe/iobuf.h>
#include <ipxe/xfer.h>
#include <ipxe/open.h>
#include <ipxe/uri.h>
#include <ipxe/features.h>
#include <ipxe/ftp.h>
/** @file
*
* File transfer protocol
*
*/
FEATURE ( FEATURE_PROTOCOL, "FTP", DHCP_EB_FEATURE_FTP, 1 );
/**
* FTP states
*
* These @b must be sequential, i.e. a successful FTP session must
* pass through each of these states in order.
*/
enum ftp_state {
FTP_CONNECT = 0,
FTP_USER,
FTP_PASS,
FTP_TYPE,
FTP_SIZE,
FTP_PASV,
FTP_RETR,
FTP_WAIT,
FTP_QUIT,
FTP_DONE,
};
/**
* An FTP request
*
*/
struct ftp_request {
/** Reference counter */
struct refcnt refcnt;
/** Data transfer interface */
struct interface xfer;
/** URI being fetched */
struct uri *uri;
/** FTP control channel interface */
struct interface control;
/** FTP data channel interface */
struct interface data;
/** Current state */
enum ftp_state state;
/** Buffer to be filled with data received via the control channel */
char *recvbuf;
/** Remaining size of recvbuf */
size_t recvsize;
/** FTP status code, as text */
char status_text[5];
/** Passive-mode parameters, as text */
char passive_text[24]; /* "aaa,bbb,ccc,ddd,eee,fff" */
/** File size, as text */
char filesize[20];
};
/**
* Free FTP request
*
* @v refcnt Reference counter
*/
static void ftp_free ( struct refcnt *refcnt ) {
struct ftp_request *ftp =
container_of ( refcnt, struct ftp_request, refcnt );
DBGC ( ftp, "FTP %p freed\n", ftp );
uri_put ( ftp->uri );
free ( ftp );
}
/**
* Mark FTP operation as complete
*
* @v ftp FTP request
* @v rc Return status code
*/
static void ftp_done ( struct ftp_request *ftp, int rc ) {
DBGC ( ftp, "FTP %p completed (%s)\n", ftp, strerror ( rc ) );
/* Close all data transfer interfaces */
intf_shutdown ( &ftp->data, rc );
intf_shutdown ( &ftp->control, rc );
intf_shutdown ( &ftp->xfer, rc );
}
/*****************************************************************************
*
* FTP control channel
*
*/
/** An FTP control channel string */
struct ftp_control_string {
/** Literal portion */
const char *literal;
/** Variable portion
*
* @v ftp FTP request
* @ret string Variable portion of string
*/
const char * ( *variable ) ( struct ftp_request *ftp );
};
/**
* Retrieve FTP pathname
*
* @v ftp FTP request
* @ret path FTP pathname
*/
static const char * ftp_uri_path ( struct ftp_request *ftp ) {
return ftp->uri->path;
}
/**
* Retrieve FTP user
*
* @v ftp FTP request
* @ret user FTP user
*/
static const char * ftp_user ( struct ftp_request *ftp ) {
static char *ftp_default_user = "anonymous";
return ftp->uri->user ? ftp->uri->user : ftp_default_user;
}
/**
* Retrieve FTP password
*
* @v ftp FTP request
* @ret password FTP password
*/
static const char * ftp_password ( struct ftp_request *ftp ) {
static char *ftp_default_password = "ipxe@ipxe.org";
return ftp->uri->password ? ftp->uri->password : ftp_default_password;
}
/** FTP control channel strings */
static struct ftp_control_string ftp_strings[] = {
[FTP_CONNECT] = { NULL, NULL },
[FTP_USER] = { "USER ", ftp_user },
[FTP_PASS] = { "PASS ", ftp_password },
[FTP_TYPE] = { "TYPE I", NULL },
[FTP_SIZE] = { "SIZE ", ftp_uri_path },
[FTP_PASV] = { "PASV", NULL },
[FTP_RETR] = { "RETR ", ftp_uri_path },
[FTP_WAIT] = { NULL, NULL },
[FTP_QUIT] = { "QUIT", NULL },
[FTP_DONE] = { NULL, NULL },
};
/**
* 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 );
}
/**
* Move to next state and send the appropriate FTP control string
*
* @v ftp FTP request
*
*/
static void ftp_next_state ( struct ftp_request *ftp ) {
struct ftp_control_string *ftp_string;
const char *literal;
const char *variable;
/* Move to next state */
if ( ftp->state < FTP_DONE )
ftp->state++;
/* Send control string if needed */
ftp_string = &ftp_strings[ftp->state];
literal = ftp_string->literal;
variable = ( ftp_string->variable ?
ftp_string->variable ( ftp ) : "" );
if ( literal ) {
DBGC ( ftp, "FTP %p sending %s%s\n", ftp, literal, variable );
xfer_printf ( &ftp->control, "%s%s\r\n", literal, variable );
}
}
/**
* Handle an FTP control channel response
*
* @v ftp FTP request
*
* This is called once we have received a complete response line.
*/
static void ftp_reply ( struct ftp_request *ftp ) {
char status_major = ftp->status_text[0];
char separator = ftp->status_text[3];
DBGC ( ftp, "FTP %p received status %s\n", ftp, ftp->status_text );
/* Ignore malformed lines */
if ( separator != ' ' )
return;
/* Ignore "intermediate" responses (1xx codes) */
if ( status_major == '1' )
return;
/* If the SIZE command is not supported by the server, we go to
* the next step.
*/
if ( ( status_major == '5' ) && ( ftp->state == FTP_SIZE ) ) {
ftp_next_state ( ftp );
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 ) ) ) ){
/* Flag protocol error and close connections */
ftp_done ( ftp, -EPROTO );
return;
}
/* Parse file size */
if ( ftp->state == FTP_SIZE ) {
size_t filesize;
char *endptr;
/* Parse size */
filesize = strtoul ( ftp->filesize, &endptr, 10 );
if ( *endptr != '\0' ) {
DBGC ( ftp, "FTP %p invalid SIZE \"%s\"\n",
ftp, ftp->filesize );
ftp_done ( ftp, -EPROTO );
return;
}
/* Use seek() to notify recipient of filesize */
DBGC ( ftp, "FTP %p file size is %zd bytes\n", ftp, filesize );
xfer_seek ( &ftp->xfer, filesize );
xfer_seek ( &ftp->xfer, 0 );
}
/* Open passive connection when we get "PASV" response */
if ( ftp->state == FTP_PASV ) {
char *ptr = ftp->passive_text;
union {
struct sockaddr_in sin;
struct sockaddr sa;
} sa;
int rc;
sa.sin.sin_family = AF_INET;
ftp_parse_value ( &ptr, ( uint8_t * ) &sa.sin.sin_addr,
sizeof ( sa.sin.sin_addr ) );
ftp_parse_value ( &ptr, ( uint8_t * ) &sa.sin.sin_port,
sizeof ( sa.sin.sin_port ) );
if ( ( rc = xfer_open_socket ( &ftp->data, SOCK_STREAM,
&sa.sa, NULL ) ) != 0 ) {
DBGC ( ftp, "FTP %p could not open data connection\n",
ftp );
ftp_done ( ftp, rc );
return;
}
}
/* Move to next state and send control string */
ftp_next_state ( ftp );
}
/**
* Handle new data arriving on FTP control channel
*
* @v ftp FTP request
* @v iob I/O buffer
* @v meta Data transfer metadata
* @ret rc Return status code
*
* Data is collected until a complete line is received, at which point
* its information is passed to ftp_reply().
*/
static int ftp_control_deliver ( struct ftp_request *ftp,
struct io_buffer *iobuf,
struct xfer_metadata *meta __unused ) {
char *data = iobuf->data;
size_t len = iob_len ( iobuf );
char *recvbuf = ftp->recvbuf;
size_t recvsize = ftp->recvsize;
char c;
while ( len-- ) {
c = *(data++);
if ( ( c == '\r' ) || ( c == '\n' ) ) {
/* End of line: call ftp_reply() to handle
* completed reply. Avoid calling ftp_reply()
* twice if we receive both \r and \n.
*/
if ( recvbuf != ftp->status_text )
ftp_reply ( ftp );
/* Start filling up the status code buffer */
recvbuf = ftp->status_text;
recvsize = sizeof ( ftp->status_text ) - 1;
} else if ( ( ftp->state == FTP_PASV ) && ( c == '(' ) ) {
/* Start filling up the passive parameter buffer */
recvbuf = ftp->passive_text;
recvsize = sizeof ( ftp->passive_text ) - 1;
} else if ( ( ftp->state == FTP_PASV ) && ( c == ')' ) ) {
/* Stop filling the passive parameter buffer */
recvsize = 0;
} else if ( ( ftp->state == FTP_SIZE ) && ( c == ' ' ) ) {
/* Start filling up the file size buffer */
recvbuf = ftp->filesize;
recvsize = sizeof ( ftp->filesize ) - 1;
} else {
/* Fill up buffer if applicable */
if ( recvsize > 0 ) {
*(recvbuf++) = c;
recvsize--;
}
}
}
/* Store for next invocation */
ftp->recvbuf = recvbuf;
ftp->recvsize = recvsize;
/* Free I/O buffer */
free_iob ( iobuf );
return 0;
}
/** FTP control channel interface operations */
static struct interface_operation ftp_control_operations[] = {
INTF_OP ( xfer_deliver, struct ftp_request *, ftp_control_deliver ),
INTF_OP ( intf_close, struct ftp_request *, ftp_done ),
};
/** FTP control channel interface descriptor */
static struct interface_descriptor ftp_control_desc =
INTF_DESC ( struct ftp_request, control, ftp_control_operations );
/*****************************************************************************
*
* FTP data channel
*
*/
/**
* Handle FTP data channel being closed
*
* @v ftp FTP request
* @v rc Reason for closure
*
* 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 ftp_request *ftp, int rc ) {
DBGC ( ftp, "FTP %p data connection closed: %s\n",
ftp, strerror ( rc ) );
/* If there was an error, close control channel and record status */
if ( rc ) {
ftp_done ( ftp, rc );
} else {
ftp_next_state ( ftp );
}
}
/** FTP data channel interface operations */
static struct interface_operation ftp_data_operations[] = {
INTF_OP ( intf_close, struct ftp_request *, ftp_data_closed ),
};
/** FTP data channel interface descriptor */
static struct interface_descriptor ftp_data_desc =
INTF_DESC_PASSTHRU ( struct ftp_request, data, ftp_data_operations,
xfer );
/*****************************************************************************
*
* Data transfer interface
*
*/
/** FTP data transfer interface operations */
static struct interface_operation ftp_xfer_operations[] = {
INTF_OP ( intf_close, struct ftp_request *, ftp_done ),
};
/** FTP data transfer interface descriptor */
static struct interface_descriptor ftp_xfer_desc =
INTF_DESC_PASSTHRU ( struct ftp_request, xfer, ftp_xfer_operations,
data );
/*****************************************************************************
*
* URI opener
*
*/
/**
* Check validity of FTP control channel string
*
* @v string String
* @ret rc Return status code
*/
static int ftp_check_string ( const char *string ) {
char c;
/* The FTP control channel is line-based. Check for invalid
* non-printable characters (e.g. newlines).
*/
while ( ( c = *(string++) ) ) {
if ( ! isprint ( c ) )
return -EINVAL;
}
return 0;
}
/**
* Initiate an FTP connection
*
* @v xfer Data transfer interface
* @v uri Uniform Resource Identifier
* @ret rc Return status code
*/
static int ftp_open ( struct interface *xfer, struct uri *uri ) {
struct ftp_request *ftp;
struct sockaddr_tcpip server;
int rc;
/* Sanity checks */
if ( ! uri->host )
return -EINVAL;
if ( ! uri->path )
return -EINVAL;
if ( ( rc = ftp_check_string ( uri->path ) ) != 0 )
return rc;
if ( uri->user && ( ( rc = ftp_check_string ( uri->user ) ) != 0 ) )
return rc;
if ( uri->password &&
( ( rc = ftp_check_string ( uri->password ) ) != 0 ) )
return rc;
/* Allocate and populate structure */
ftp = zalloc ( sizeof ( *ftp ) );
if ( ! ftp )
return -ENOMEM;
ref_init ( &ftp->refcnt, ftp_free );
intf_init ( &ftp->xfer, &ftp_xfer_desc, &ftp->refcnt );
intf_init ( &ftp->control, &ftp_control_desc, &ftp->refcnt );
intf_init ( &ftp->data, &ftp_data_desc, &ftp->refcnt );
ftp->uri = uri_get ( uri );
ftp->recvbuf = ftp->status_text;
ftp->recvsize = sizeof ( ftp->status_text ) - 1;
DBGC ( ftp, "FTP %p fetching %s\n", ftp, ftp->uri->path );
/* Open control connection */
memset ( &server, 0, sizeof ( server ) );
server.st_port = htons ( uri_port ( uri, FTP_PORT ) );
if ( ( rc = xfer_open_named_socket ( &ftp->control, SOCK_STREAM,
( struct sockaddr * ) &server,
uri->host, NULL ) ) != 0 )
goto err;
/* Attach to parent interface, mortalise self, and return */
intf_plug_plug ( &ftp->xfer, xfer );
ref_put ( &ftp->refcnt );
return 0;
err:
DBGC ( ftp, "FTP %p could not create request: %s\n",
ftp, strerror ( rc ) );
ftp_done ( ftp, rc );
ref_put ( &ftp->refcnt );
return rc;
}
/** FTP URI opener */
struct uri_opener ftp_uri_opener __uri_opener = {
.scheme = "ftp",
.open = ftp_open,
};
