/**
* @brief processes tftp write operation
* @param upcb: pointer on upd pcb
* @param to: pointer on remote IP address
* @param to_port: pointer on remote udp port
* @param FileName: pointer on filename to be written
* @retval error code
*/
int tftp_process_write(struct udp_pcb *upcb, const ip_addr_t *to, unsigned short to_port, char *FileName)
{
tftp_connection_args *args = NULL;
char *path = malloc(strlen(FileName) + sizeof(TFTPD_PATH) + 1);
if(!path)
return 0;
strcpy(path, TFTPD_PATH);
strcat(path, FileName);
/* Can not create file */
if (f_open(&file_CR, (const TCHAR*)FileName, FA_CREATE_ALWAYS|FA_WRITE) != FR_OK)
{
tftp_send_error_message(upcb, to, to_port, TFTP_ERR_NOTDEFINED);
tftp_cleanup_wr(upcb, args);
return 0;
}
args = mem_malloc(sizeof *args);
if (!args)
{
tftp_send_error_message(upcb, to, to_port, TFTP_ERR_NOTDEFINED);
tftp_cleanup_wr(upcb, args);
return 0;
}
args->op = TFTP_WRQ;
args->to_ip.addr = to->addr;
args->to_port = to_port;
/* the block # used as a positive response to a WRQ is _always_ 0!!! (see RFC1350) */
args->block = 0;
args->tot_bytes = 0;
/* set callback for receives on this UDP PCB */
udp_recv(upcb, wrq_recv_callback, args);
/* initiate the write transaction by sending the first ack */
tftp_send_ack_packet(upcb, to, to_port, args->block);
return 0;
}
int tftp_process_write(struct udp_pcb *upcb, struct ip_addr *to, int to_port, char *FileName)
{
tftp_connection_args *args = NULL;
/* If Could not open the file which will be transmitted */
if (file_fopen(&file_CR, &efs2.myFs, FileName, 'w') != 0)
{
tftp_send_error_message(upcb, to, to_port, TFTP_ERR_FILE_ALREADY_EXISTS);
tftp_cleanup_wr(upcb, args);
return 0;
}
/* This function is called from a callback,
* therefore interrupts are disabled,
* therefore we can use regular malloc */
args = mem_malloc(sizeof *args);
if (!args)
{
tftp_send_error_message(upcb, to, to_port, TFTP_ERR_NOTDEFINED);
tftp_cleanup_wr(upcb, args);
return 0;
}
args->op = TFTP_WRQ;
args->to_ip.addr = to->addr;
args->to_port = to_port;
/* the block # used as a positive response to a WRQ is _always_ 0!!! (see RFC1350) */
args->block = 0;
args->tot_bytes = 0;
/* set callback for receives on this UDP PCB (Protocol Control Block) */
udp_recv(upcb, wrq_recv_callback, args);
/* initiate the write transaction by sending the first ack */
tftp_send_ack_packet(upcb, to, to_port, args->block);
return 0;
}
/**
* @brief receive callback during tftp write operation (not on standard port 69)
* @param arg: pointer on argument passed to callback
* @param udp_pcb: pointer on the udp pcb
* @param pkt_buf: pointer on the received pbuf
* @param addr: pointer on remote IP address
* @param port: pointer on remote port
* @retval None
*/
void wrq_recv_callback(void *arg, struct udp_pcb *upcb, struct pbuf *pkt_buf, struct ip_addr *addr, u16_t port)
{
tftp_connection_args *args = (tftp_connection_args *)arg;
int n = 0;
/* we expect to receive only one pbuf (pbuf size should be
configured > max TFTP frame size */
if (pkt_buf->len != pkt_buf->tot_len)
{
return;
}
/* Does this packet have any valid data to write? */
if ((pkt_buf->len > TFTP_DATA_PKT_HDR_LEN) &&
(tftp_extract_block(pkt_buf->payload) == (args->block + 1)))
{
/* write the received data to the file */
memcpy((char*)TempBuffer, (char*)pkt_buf->payload + TFTP_DATA_PKT_HDR_LEN, pkt_buf->len - TFTP_DATA_PKT_HDR_LEN);
f_write(&file_CR, (char*)TempBuffer, pkt_buf->len - TFTP_DATA_PKT_HDR_LEN, (UINT*)&n);
if (n <= 0)
{
tftp_send_error_message(upcb, addr, port, TFTP_ERR_FILE_NOT_FOUND);
/* close the connection */
tftp_cleanup_wr(upcb, args); /* close the connection */
}
/* update our block number to match the block number just received */
args->block++;
/* update total bytes */
(args->tot_bytes) += (pkt_buf->len - TFTP_DATA_PKT_HDR_LEN);
}
else if (tftp_extract_block(pkt_buf->payload) == (args->block + 1))
{
/* update our block number to match the block number just received */
args->block++;
}
/* Send the appropriate ACK pkt (the block number sent in the ACK pkt echoes
* the block number of the DATA pkt we just received - see RFC1350)
* NOTE!: If the DATA pkt we received did not have the appropriate block
* number, then the args->block (our block number) is never updated and
* we simply send "duplicate ACK" which has the same block number as the
* last ACK pkt we sent. This lets the host know that we are still waiting
* on block number args->block+1.
*/
tftp_send_ack_packet(upcb, addr, port, args->block);
/* If the last write returned less than the maximum TFTP data pkt length,
* then we've received the whole file and so we can quit (this is how TFTP
* signals the end of a transfer!)
*/
if (pkt_buf->len < TFTP_DATA_PKT_LEN_MAX)
{
tftp_cleanup_wr(upcb, args);
pbuf_free(pkt_buf);
}
else
{
pbuf_free(pkt_buf);
return;
}
}
void wrq_recv_callback(void *_args, struct udp_pcb *upcb, struct pbuf *pkt_buf, struct ip_addr *addr, u16_t port)
{
tftp_connection_args *args = (tftp_connection_args *)_args;
int n = 0;
if (pkt_buf->len != pkt_buf->tot_len)
{
return;
}
/* Does this packet have any valid data to write? */
if ((pkt_buf->len > TFTP_DATA_PKT_HDR_LEN) &&
(tftp_extract_block(pkt_buf->payload) == (args->block + 1)))
{
/* write the received data to the file */
n = file_write(&file_CR,
pkt_buf->len - TFTP_DATA_PKT_HDR_LEN,
(euint8*)pkt_buf->payload + TFTP_DATA_PKT_HDR_LEN);
if (n <= 0)
{
tftp_send_error_message(upcb, addr, port, TFTP_ERR_FILE_NOT_FOUND);
/* close the connection */
tftp_cleanup_wr(upcb, args); /* close the connection */
}
/* update our block number to match the block number just received */
args->block++;
/* update total bytes */
(args->tot_bytes) += (pkt_buf->len - TFTP_DATA_PKT_HDR_LEN);
/* This is a valid pkt but it has no data. This would occur if the file being
written is an exact multiple of 512 bytes. In this case, the args->block
value must still be updated, but we can skip everything else. */
}
else if (tftp_extract_block(pkt_buf->payload) == (args->block + 1))
{
/* update our block number to match the block number just received */
args->block++;
}
/* SEndTransferthe appropriate ACK pkt (the block number sent in the ACK pkt echoes
* the block number of the DATA pkt we just received - see RFC1350)
* NOTE!: If the DATA pkt we received did not have the appropriate block
* number, then the args->block (our block number) is never updated and
* we simply sEndTransfera "duplicate ACK" which has the same block number as the
* last ACK pkt we sent. This lets the host know that we are still waiting
* on block number args->block+1. */
tftp_send_ack_packet(upcb, addr, port, args->block);
/* If the last write returned less than the maximum TFTP data pkt length,
* then we've received the whole file and so we can quit (this is how TFTP
* signals the EndTransferof a transfer!)
*/
if (pkt_buf->len < TFTP_DATA_PKT_LEN_MAX)
{
tftp_cleanup_wr(upcb, args);
pbuf_free(pkt_buf);
}
else
{
pbuf_free(pkt_buf);
return;
}
}
