/*
* Trivial File Transfer Protocol (RFC 1350)
*
* Transfer file to/from remote host
*
* W. Eric Norum
* Saskatchewan Accelerator Laboratory
* University of Saskatchewan
* Saskatoon, Saskatchewan, CANADA
* eric@skatter.usask.ca
*
* $Id$
*/
#include <stdio.h>
#include <errno.h>
#include <malloc.h>
#include <string.h>
#include <unistd.h>
#include <rtems.h>
#include <rtems/libio.h>
#include <rtems/rtems_bsdnet.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
/*
* Range of UDP ports to try
*/
#define UDP_PORT_BASE 3180
/*
* Pathname prefix
*/
#define TFTP_PATHNAME_PREFIX "/TFTP/"
/*
* Default limits
*/
#define PACKET_REPLY_MILLISECONDS 6000
#define OPEN_RETRY_LIMIT 10
#define IO_RETRY_LIMIT 10
/*
* TFTP opcodes
*/
#define TFTP_OPCODE_RRQ 1
#define TFTP_OPCODE_WRQ 2
#define TFTP_OPCODE_DATA 3
#define TFTP_OPCODE_ACK 4
#define TFTP_OPCODE_ERROR 5
/*
* Largest data transfer
*/
#define TFTP_BUFSIZE 512
/*
* Packets transferred between machines
*/
union tftpPacket {
/*
* RRQ/WRQ packet
*/
struct tftpRWRQ {
rtems_unsigned16 opcode;
char filename_mode[TFTP_BUFSIZE];
} tftpRWRQ;
/*
* DATA packet
*/
struct tftpDATA {
rtems_unsigned16 opcode;
rtems_unsigned16 blocknum;
rtems_unsigned8 data[TFTP_BUFSIZE];
} tftpDATA;
/*
* ACK packet
*/
struct tftpACK {
rtems_unsigned16 opcode;
rtems_unsigned16 blocknum;
} tftpACK;
/*
* ERROR packet
*/
struct tftpERROR {
rtems_unsigned16 opcode;
rtems_unsigned16 errorCode;
char errorMessage[TFTP_BUFSIZE];
} tftpERROR;
};
/*
* State of each TFTP stream
*/
struct tftpStream {
/*
* Buffer for storing most recently-received packet
*/
union tftpPacket pkbuf;
/*
* Last block number received
*/
rtems_unsigned16 blocknum;
/*
* Data transfer socket
*/
int socket;
struct sockaddr_in myAddress;
struct sockaddr_in farAddress;
/*
* Indices into buffer
*/
int nleft;
int nused;
/*
* Flags
*/
int firstReply;
int eof;
};
/*
* Number of streams open at the same time
*/
static rtems_id tftp_mutex;
static int nStreams;
static struct tftpStream ** volatile tftpStreams;
/*
* Initialize the TFTP driver
*/
rtems_device_driver rtems_tftp_initialize(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *pargp
)
{
rtems_status_code sc;
sc = rtems_semaphore_create (rtems_build_name('T', 'F', 'T', 'P'),
1,
RTEMS_FIFO |
RTEMS_BINARY_SEMAPHORE |
RTEMS_NO_INHERIT_PRIORITY |
RTEMS_NO_PRIORITY_CEILING |
RTEMS_LOCAL,
0,
&tftp_mutex);
if (sc != RTEMS_SUCCESSFUL)
return sc;
rtems_io_register_name (TFTP_PATHNAME_PREFIX, major, minor);
return RTEMS_SUCCESSFUL;
}
/*
* Set error message
* This RTEMS/UNIX error mapping needs to be fixed!
*/
static void
tftpSetErrno (struct tftpStream *tp)
{
unsigned int tftpError;
static const int errorMap[] = {
0,
ENOENT,
EPERM,
ENOSPC,
EINVAL,
ENXIO,
EEXIST,
ESRCH,
0,
};
tftpError = ntohs (tp->pkbuf.tftpERROR.errorCode);
if (tftpError < (sizeof errorMap / sizeof errorMap[0]))
errno = errorMap[tftpError];
else
errno = 1000 + tftpError;
}
/*
* Send a message to make the other end shut up
*/
static void
sendStifle (struct tftpStream *tp, struct sockaddr_in *to)
{
int len;
/*
* Create the error packet (Unknown transfer ID).
*/
tp->pkbuf.tftpERROR.opcode = htons (TFTP_OPCODE_ERROR);
tp->pkbuf.tftpERROR.errorCode = htons (5);
len = sizeof tp->pkbuf.tftpERROR.opcode +
sizeof tp->pkbuf.tftpERROR.errorCode + 1;
len += sprintf (tp->pkbuf.tftpERROR.errorMessage, "GO AWAY");
/*
* Send it
*/
sendto (tp->socket, (char *)&tp->pkbuf, len, 0,
(struct sockaddr *)to, sizeof *to);
}
/*
* Wait for a data packet
*/
static int
getPacket (struct tftpStream *tp)
{
int len;
struct timeval tv;
tv.tv_sec = 6;
tv.tv_usec = 0;
setsockopt (tp->socket, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof tv);
for (;;) {
union {
struct sockaddr s;
struct sockaddr_in i;
} from;
int fromlen = sizeof from;
len = recvfrom (tp->socket, (char *)&tp->pkbuf,
sizeof tp->pkbuf, 0,
&from.s, &fromlen);
if (len < 0)
break;
if (from.i.sin_addr.s_addr == tp->farAddress.sin_addr.s_addr) {
if (tp->firstReply) {
tp->firstReply = 0;
tp->farAddress.sin_port = from.i.sin_port;
}
if (tp->farAddress.sin_port == from.i.sin_port)
break;
}
/*
* Packet is from someone with whom we are
* not interested. Tell them to go away.
*/
sendStifle (tp, &from.i);
}
tv.tv_sec = 0;
setsockopt (tp->socket, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof tv);
return len;
}
/*
* Send an acknowledgement
*/
static int
sendAck (struct tftpStream *tp)
{
/*
* Create the acknowledgement
*/
tp->pkbuf.tftpACK.opcode = htons (TFTP_OPCODE_ACK);
tp->pkbuf.tftpACK.blocknum = htons (tp->blocknum);
/*
* Send it
*/
if (sendto (tp->socket, (char *)&tp->pkbuf, sizeof tp->pkbuf.tftpACK, 0,
(struct sockaddr *)&tp->farAddress,
sizeof tp->farAddress) < 0)
return errno;
return 0;
}
/*
* Release a stream and clear the pointer to it
*/
static void
releaseStream (int s)
{
rtems_semaphore_obtain (tftp_mutex, RTEMS_WAIT, RTEMS_NO_TIMEOUT);
free (tftpStreams[s]);
tftpStreams[s] = NULL;
rtems_semaphore_release (tftp_mutex);
}
/*
* Open a TFTP stream
*/
rtems_device_driver rtems_tftp_open(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *pargp
)
{
rtems_libio_open_close_args_t *ap = pargp;
struct tftpStream *tp;
int retryCount;
rtems_unsigned32 farAddress;
int s;
int len;
char *cp1, *cp2;
char *remoteFilename;
rtems_interval now;
rtems_status_code sc;
/*
* Read-only for now
*/
if (ap->flags & LIBIO_FLAGS_WRITE)
return RTEMS_NOT_IMPLEMENTED;
/*
* Pick apart the name into a host:pathname pair
*/
if (strlen (ap->iop->pathname) <= strlen (TFTP_PATHNAME_PREFIX))
return RTEMS_INVALID_NAME;
cp2 = ap->iop->pathname + strlen (TFTP_PATHNAME_PREFIX);
if (*cp2 == '/') {
farAddress = rtems_bsdnet_bootp_server_address.s_addr;
}
else {
char *hostname;
cp1 = cp2;
while (*cp2 != '/') {
if (*cp2 == '\0')
return RTEMS_INVALID_NAME;
cp2++;
}
len = cp2 - cp1;
hostname = malloc (len + 1);
if (hostname == NULL)
return RTEMS_NO_MEMORY;
strncpy (hostname, cp1, len);
hostname[len] = '\0';
farAddress = inet_addr (hostname);
free (hostname);
}
if ((farAddress == 0) || (farAddress == ~0))
return RTEMS_INVALID_NAME;
if (*++cp2 == '\0')
return RTEMS_INVALID_NAME;
remoteFilename = cp2;
if (strlen (remoteFilename) > (TFTP_BUFSIZE - 10))
return RTEMS_INVALID_NAME;
/*
* Find a free stream
*/
sc = rtems_semaphore_obtain (tftp_mutex, RTEMS_WAIT, RTEMS_NO_TIMEOUT);
if (sc != RTEMS_SUCCESSFUL)
return sc;
for (s = 0 ; s < nStreams ; s++) {
if (tftpStreams[s] == NULL)
break;
}
if (s == nStreams) {
/*
* Reallocate stream pointers
* Guard against the case where realloc() returns NULL.
*/
struct tftpStream **np;
np = realloc (tftpStreams, ++nStreams * sizeof *tftpStreams);
if (np == NULL) {
rtems_semaphore_release (tftp_mutex);
return RTEMS_NO_MEMORY;
}
tftpStreams = np;
}
tp = tftpStreams[s] = malloc (sizeof (struct tftpStream));
rtems_semaphore_release (tftp_mutex);
if (tp == NULL)
return RTEMS_NO_MEMORY;
ap->iop->data0 = s;
ap->iop->data1 = tp;
/*
* Create the socket
*/
if ((tp->socket = socket (AF_INET, SOCK_DGRAM, 0)) < 0) {
releaseStream (s);
return RTEMS_TOO_MANY;
}
/*
* Bind the socket to a local address
*/
retryCount = 0;
rtems_clock_get (RTEMS_CLOCK_GET_TICKS_SINCE_BOOT, &now);
for (;;) {
int try = (now + retryCount) % 10;
tp->myAddress.sin_family = AF_INET;
tp->myAddress.sin_port = htons (UDP_PORT_BASE + nStreams * try + minor);
tp->myAddress.sin_addr.s_addr = htonl (INADDR_ANY);
if (bind (tp->socket, (struct sockaddr *)&tp->myAddress, sizeof tp->myAddress) >= 0)
break;
if (++retryCount == 10) {
close (tp->socket);
releaseStream (minor);
return RTEMS_RESOURCE_IN_USE;
}
}
/*
* Set the UDP destination to the TFTP server
* port on the remote machine.
*/
tp->farAddress.sin_family = AF_INET;
tp->farAddress.sin_addr.s_addr = farAddress;
tp->farAddress.sin_port = htons (69);
/*
* Start the transfer
*/
tp->firstReply = 1;
for (;;) {
/*
* Create the request
*/
tp->pkbuf.tftpRWRQ.opcode = htons (TFTP_OPCODE_RRQ);
cp1 = tp->pkbuf.tftpRWRQ.filename_mode;
cp2 = remoteFilename;
while ((*cp1++ = *cp2++) != '\0')
continue;
cp2 = "octet";
while ((*cp1++ = *cp2++) != '\0')
continue;
len = cp1 - (char *)&tp->pkbuf.tftpRWRQ;
/*
* Send the request
*/
if (sendto (tp->socket, (char *)&tp->pkbuf, len, 0,
(struct sockaddr *)&tp->farAddress,
sizeof tp->farAddress) < 0) {
close (tp->socket);
releaseStream (minor);
return RTEMS_UNSATISFIED;
}
/*
* Get reply
*/
len = getPacket (tp);
if (len >= (int) sizeof tp->pkbuf.tftpACK) {
int opcode = ntohs (tp->pkbuf.tftpDATA.opcode);
if ((opcode == TFTP_OPCODE_DATA)
&& (ntohs (tp->pkbuf.tftpDATA.blocknum) == 1)) {
tp->nused = 0;
tp->blocknum = 1;
tp->nleft = len - 2 * sizeof (rtems_unsigned16);
tp->eof = (tp->nleft < TFTP_BUFSIZE);
if (sendAck (tp) != 0) {
close (tp->socket);
releaseStream (minor);
return RTEMS_UNSATISFIED;
}
break;
}
if (opcode == TFTP_OPCODE_ERROR) {
tftpSetErrno (tp);
close (tp->socket);
releaseStream (ap->iop->data0);
return RTEMS_INTERNAL_ERROR;
}
}
/*
* Keep trying
*/
if (++retryCount >= OPEN_RETRY_LIMIT) {
close (tp->socket);
releaseStream (minor);
return RTEMS_UNSATISFIED;
}
}
return RTEMS_SUCCESSFUL;
}
/*
* Read from a TFTP stream
*/
rtems_device_driver rtems_tftp_read(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *pargp
)
{
rtems_libio_rw_args_t *ap = pargp;
char *bp;
struct tftpStream *tp;
int retryCount;
int nwant;
tp = ap->iop->data1;
/*
* Read till user request is satisfied or EOF is reached
*/
bp = ap->buffer;
nwant = ap->count;
while (nwant) {
if (tp->nleft) {
int count;
if (nwant < tp->nleft)
count = nwant;
else
count = tp->nleft;
memcpy (bp, &tp->pkbuf.tftpDATA.data[tp->nused], count);
tp->nused += count;
tp->nleft -= count;
bp += count;
nwant -= count;
if (nwant == 0)
break;
}
if (tp->eof)
break;
/*
* Wait for the next packet
*/
retryCount = 0;
for (;;) {
int len = getPacket (tp);
if (len >= (int)sizeof tp->pkbuf.tftpACK) {
int opcode = ntohs (tp->pkbuf.tftpDATA.opcode);
rtems_unsigned16 nextBlock = tp->blocknum + 1;
if ((opcode == TFTP_OPCODE_DATA)
&& (ntohs (tp->pkbuf.tftpDATA.blocknum) == nextBlock)) {
tp->nused = 0;
tp->nleft = len - 2 * sizeof (rtems_unsigned16);
tp->eof = (tp->nleft < TFTP_BUFSIZE);
tp->blocknum++;
if (sendAck (tp) != 0)
return RTEMS_IO_ERROR;
break;
}
if (opcode == TFTP_OPCODE_ERROR) {
tftpSetErrno (tp);
return RTEMS_INTERNAL_ERROR;
}
}
/*
* Keep trying?
*/
if (++retryCount == IO_RETRY_LIMIT)
return RTEMS_IO_ERROR;
if (sendAck (tp) != 0)
return RTEMS_IO_ERROR;
}
}
ap->bytes_moved = ap->count - nwant;
return RTEMS_SUCCESSFUL;
}
/*
* Close a TFTP stream
*/
rtems_device_driver rtems_tftp_close(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *pargp
)
{
rtems_libio_open_close_args_t *ap = pargp;
struct tftpStream *tp = ap->iop->data1;;
if (!tp->eof && !tp->firstReply) {
/*
* Tell the other end to stop
*/
rtems_interval ticksPerSecond;
sendStifle (tp, &tp->farAddress);
rtems_clock_get (RTEMS_CLOCK_GET_TICKS_PER_SECOND, &ticksPerSecond);
rtems_task_wake_after (1 + ticksPerSecond / 10);
}
close (tp->socket);
releaseStream (ap->iop->data0);
return RTEMS_SUCCESSFUL;
}
rtems_device_driver rtems_tftp_write(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *pargp
)
{
return RTEMS_NOT_CONFIGURED;
}
rtems_device_driver rtems_tftp_control(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *pargp
)
{
return RTEMS_NOT_CONFIGURED;
}