/****************************************************************************
* apps/netutils/tftpc/tftpc_get.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <stdint.h>
#include <stdbool.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <debug.h>
#include <arpa/inet.h>
#include <nuttx/net/netconfig.h>
#include "netutils/tftp.h"
#include "tftpc_internal.h"
#if defined(CONFIG_NET) && defined(CONFIG_NET_UDP)
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#define TFTP_RETRIES 3
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: tftp_parsedatapacket
****************************************************************************/
static inline int tftp_parsedatapacket(FAR const uint8_t *packet,
FAR uint16_t *opcode,
FAR uint16_t *blockno)
{
*opcode = (uint16_t)packet[0] << 8 | (uint16_t)packet[1];
if (*opcode == TFTP_DATA)
{
*blockno = (uint16_t)packet[2] << 8 | (uint16_t)packet[3];
return OK;
}
#ifdef CONFIG_DEBUG_NET_WARN
else if (*opcode == TFTP_ERR)
{
tftp_parseerrpacket(packet);
}
#endif
return ERROR;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: tftpget_cb
*
* Input Parameters:
* remote - The name of the file on the TFTP server.
* addr - The IP address of the server in network order
* binary - TRUE: Perform binary ('octet') transfer
* FALSE: Perform text ('netascii') transfer
* cb - callback that will be called with data packets
* ctx - pointer passed to the previous callback
*
****************************************************************************/
int tftpget_cb(FAR const char *remote, in_addr_t addr, bool binary,
tftp_callback_t tftp_cb, FAR void *ctx)
{
struct sockaddr_in server; /* The address of the TFTP server */
struct sockaddr_in from; /* The address the last UDP message recv'd from */
FAR uint8_t *packet; /* Allocated memory to hold one packet */
uint16_t blockno = 0; /* The current transfer block number */
uint16_t opcode; /* Received opcode */
uint16_t rblockno; /* Received block number */
int len; /* Generic length */
int sd; /* Socket descriptor for socket I/O */
int retry; /* Retry counter */
int nbytesrecvd = 0; /* The number of bytes received in the packet */
int ndatabytes; /* The number of data bytes received */
int result = ERROR; /* Assume failure */
int ret; /* Generic return status */
/* Allocate the buffer to used for socket/disk I/O */
packet = (FAR uint8_t *)zalloc(TFTP_IOBUFSIZE);
if (!packet)
{
nerr("ERROR: packet memory allocation failure\n");
errno = ENOMEM;
return result;
}
/* Initialize a UDP socket and setup the server address */
sd = tftp_sockinit(&server, addr);
if (sd < 0)
{
goto errout;
}
/* Then enter the transfer loop. Loop until the entire file has
* been received or until an error occurs.
*/
do
{
/* Increment the TFTP block number for the next transfer */
blockno++;
/* Send the next block if the file within a loop. We will
* retry up to TFTP_RETRIES times before giving up on the
* transfer.
*/
for (retry = 0; retry < TFTP_RETRIES; retry++)
{
/* Send the read request using the well-known port number before
* receiving the first block. Each retry of the first block will
* re-send the request.
*/
if (blockno == 1)
{
len = tftp_mkreqpacket(packet, TFTP_RRQ, remote,
binary);
server.sin_port = HTONS(CONFIG_NETUTILS_TFTP_PORT);
ret = tftp_sendto(sd, packet, len, &server);
if (ret != len)
{
goto errout_with_sd;
}
/* Subsequent sendto will use the port number selected by the
* TFTP server in the DATA packet. Setting the server port to
* zero here indicates that we have not yet received the server
* port number.
*/
server.sin_port = 0;
}
/* Get the next packet from the server */
nbytesrecvd = tftp_recvfrom(sd, packet, TFTP_IOBUFSIZE, &from);
/* Check if anything valid was received */
if (nbytesrecvd > 0)
{
/* Verify the sender address and port number */
if (server.sin_addr.s_addr != from.sin_addr.s_addr)
{
ninfo("Invalid address in DATA\n");
retry--;
continue;
}
if (server.sin_port && server.sin_port != from.sin_port)
{
ninfo("Invalid port in DATA\n");
len = tftp_mkerrpacket(packet, TFTP_ERR_UNKID,
TFTP_ERRST_UNKID);
ret = tftp_sendto(sd, packet, len, &from);
retry--;
continue;
}
/* Parse the incoming DATA packet */
if (nbytesrecvd < TFTP_DATAHEADERSIZE)
{
/* Packet is not big enough to be parsed */
ninfo("Tiny data packet ignored\n");
continue;
}
if (tftp_parsedatapacket(packet, &opcode, &rblockno) != OK ||
blockno != rblockno)
{
/* Opcode is not TFTP_DATA or the block number is
* unexpected.
*/
ninfo("Parse failure\n");
if (opcode > TFTP_MAXRFC1350)
{
len = tftp_mkerrpacket(packet, TFTP_ERR_ILLEGALOP,
TFTP_ERRST_ILLEGALOP);
ret = tftp_sendto(sd, packet, len, &from);
}
continue;
}
/* Replace the server port to the one in the good response */
if (!server.sin_port)
{
server.sin_port = from.sin_port;
}
/* Then break out of the loop */
break;
}
}
/* Did we exhaust all of the retries? */
if (retry == TFTP_RETRIES)
{
ninfo("Retry limit exceeded\n");
goto errout_with_sd;
}
/* Write the received data chunk to the file */
ndatabytes = nbytesrecvd - TFTP_DATAHEADERSIZE;
tftp_dumpbuffer("Recvd DATA",
packet + TFTP_DATAHEADERSIZE, ndatabytes);
if (tftp_cb(ctx, 0, packet + TFTP_DATAHEADERSIZE, ndatabytes) < 0)
{
goto errout_with_sd;
}
/* Send the acknowledgment */
len = tftp_mkackpacket(packet, blockno);
ret = tftp_sendto(sd, packet, len, &server);
if (ret != len)
{
goto errout_with_sd;
}
ninfo("ACK blockno %d\n", blockno);
}
while (ndatabytes >= TFTP_DATASIZE);
/* Return success */
result = OK;
errout_with_sd:
close(sd);
errout:
free(packet);
return result;
}
/****************************************************************************
* Name: tftp_write
****************************************************************************/
static ssize_t tftp_write(FAR void *ctx, uint32_t offset, FAR uint8_t *buf,
size_t len)
{
int fd = (intptr_t)ctx;
size_t left = len;
ssize_t nbyteswritten;
while (left > 0)
{
/* Write the data... repeating the write in the event that it was
* interrupted by a signal.
*/
do
{
nbyteswritten = write(fd, buf, left);
}
while (nbyteswritten < 0 && errno == EINTR);
/* Check for non-EINTR errors */
if (nbyteswritten < 0)
{
nerr("ERROR: write failed: %d\n", errno);
return ERROR;
}
/* Handle partial writes */
ninfo("Wrote %zd bytes to file\n", nbyteswritten);
left -= nbyteswritten;
buf += nbyteswritten;
}
return len;
}
/****************************************************************************
* Name: tftpget
*
* Input Parameters:
* remote - The name of the file on the TFTP server.
* local - Path to the location on a mounted filesystem where the file
* will be stored.
* addr - The IP address of the server in network order
* binary - TRUE: Perform binary ('octect') transfer
* FALSE: Perform text ('netascii') transfer
*
****************************************************************************/
int tftpget(FAR const char *remote, FAR const char *local, in_addr_t addr,
bool binary)
{
int fd; /* File descriptor for file I/O */
int result = ERROR; /* Generic return status */
/* Open the file for writing */
fd = open(local, O_WRONLY | O_CREAT | O_TRUNC, 0666);
if (fd < 0)
{
nerr("ERROR: open failed: %d\n", errno);
goto errout;
}
result = tftpget_cb(remote, addr, binary, tftp_write,
(FAR void *)(intptr_t)fd);
close(fd);
errout:
return result;
}
#endif /* CONFIG_NET && CONFIG_NET_UDP */