void TFTPSRV_service_transaction
(
TFTPSRV_STATE_STRUCT_PTR tftpsrv_ptr,
/* [IN/OUT] The TFTP Server state */
TFTP_TRANS_STRUCT_PTR trans_ptr
/* [IN/OUT] The transaction state */
)
{ /* Body */
sockaddr_in sockaddr_tftp;
uint32_t block_num;
int32_t pkt_len, write_len;
uint16_t sockaddrlen, pkt_op;
/* receive the datagram */
sockaddrlen = sizeof(sockaddr_tftp);
pkt_len = recvfrom(trans_ptr->SOCK, tftpsrv_ptr->BUFFER,
TFTP_MAX_MESSAGE_SIZE, 0,(sockaddr *)&sockaddr_tftp, &sockaddrlen);
if (pkt_len == RTCS_ERROR) {
return;
} /* Endif */
/* verify the sender's address and port */
if ((trans_ptr->ADDR.sin_port != sockaddr_tftp.sin_port) ||
(trans_ptr->ADDR.sin_addr.s_addr != sockaddr_tftp.sin_addr.s_addr)) {
TFTP_SEND(tftpsrv_ptr->SRV_SOCK, _tftp_error_tid, sockaddr_tftp);
return;
} /* Endif */
/* get op and block number */
if (pkt_len < sizeof(TFTP_HEADER)) {
TFTP_SEND(trans_ptr->SOCK, _tftp_error_tid, sockaddr_tftp);
return;
} /* Endif */
pkt_op = mqx_ntohs(tftpsrv_ptr->BUFFER);
block_num = mqx_ntohs(tftpsrv_ptr->BUFFER + 2);
/* verify the requested operation */
if (pkt_op != trans_ptr->RECV_OP) {
if (pkt_op != TFTPOP_ERROR) {
TFTP_SEND(trans_ptr->SOCK, _tftp_error_op, sockaddr_tftp);
} /* Endif */
TFTPSRV_close_transaction(tftpsrv_ptr, trans_ptr);
return;
} /* Endif */
switch (pkt_op) {
case TFTPOP_DATA:
/* We are servicing a write request from a TFTP Client here */
if (block_num == trans_ptr->BLOCK) {
pkt_len -= sizeof(TFTP_HEADER);
write_len = RTCS_io_write(trans_ptr->TRANS_FILE_PTR,
tftpsrv_ptr->BUFFER + sizeof(TFTP_HEADER),
pkt_len);
fflush(trans_ptr->TRANS_FILE_PTR);
if (write_len != pkt_len) {
TFTP_SEND(trans_ptr->SOCK, _tftp_error_srv, trans_ptr->ADDR);
TFTPSRV_close_transaction(tftpsrv_ptr, trans_ptr);
return;
} /* Endif */
TFTPSRV_build_ACK(trans_ptr);
trans_ptr->EXIT = (write_len < sizeof(TFTP_PACKET) - sizeof(TFTP_HEADER));
TFTPSRV_timer_cancel(tftpsrv_ptr, trans_ptr);
TFTPSRV_timer_start(tftpsrv_ptr, trans_ptr, TFTP_timeout_update(&trans_ptr->XMIT_TIMER));
TFTPSRV_send(trans_ptr);
} else if (block_num == trans_ptr->BLOCK - 1) {
TFTPSRV_timer_cancel(tftpsrv_ptr, trans_ptr);
TFTPSRV_timer_start(tftpsrv_ptr, trans_ptr, TFTP_timeout_restart(&trans_ptr->XMIT_TIMER));
TFTPSRV_send(trans_ptr);
} /* Endif */
break;
case TFTPOP_ACK:
/* We are servicing a read request */
if (block_num == trans_ptr->BLOCK) {
if (trans_ptr->EXIT) {
/* We've received the last ACK, exit */
TFTPSRV_close_transaction(tftpsrv_ptr, trans_ptr);
return;
} /* Endif */
TFTPSRV_build_DATA(trans_ptr);
if (trans_ptr->SEND_SIZE < sizeof(TFTP_HEADER)) {
TFTP_SEND(trans_ptr->SOCK, _tftp_error_srv, sockaddr_tftp);
TFTPSRV_close_transaction(tftpsrv_ptr, trans_ptr);
return;
} /* Endif */
TFTPSRV_timer_cancel(tftpsrv_ptr, trans_ptr);
TFTPSRV_timer_start(tftpsrv_ptr, trans_ptr, TFTP_timeout_update(&trans_ptr->XMIT_TIMER));
TFTPSRV_send(trans_ptr);
} /* Endif */
break;
} /* Endswitch */
} /* Endbody */
uchar_ptr TFTP_read
(
uint_32_ptr size
/* [OUT] number of bytes read, or error code */
)
{ /* Body */
uint_32 sock;
sockaddr_in remote_addr;
uint_16 remote_size;
uint_16 ack_block;
uint_16 pkt_op, pkt_block;
uint_32 pkt_size;
uint_32 time_left;
boolean expired;
#if TFTP_TIMEOUT_RETRIES
uint_32 retries = 0;
#endif
ack_block = ntohs(TFTP_config.ACK.BLOCK);
TFTP_timeout_restart(&TFTP_config.TIMEOUT);
for (;;) {
/* Check for timeout */
time_left = TFTP_timeout_left(&TFTP_config.TIMEOUT, &expired);
if (expired) {
#if TFTP_TIMEOUT_RETRIES
retries++;
if (retries > TFTP_TIMEOUT_RETRIES) {
*size = RTCSERR_TFTP_TIMEOUT;
TFTP_close();
return NULL;
} /* Endif */
#endif
/* Retransmit the last packet */
TFTP_RESEND();
} /* Endif */
/* Wait for a packet */
sock = TFTP_WAIT(time_left);
/* Timeout -- retransmit last packet */
if (sock != TFTP_config.SOCK) {
continue;
} /* Endif */
remote_size = sizeof(remote_addr);
pkt_size = TFTP_RECV(TFTP_config.PACKET);
pkt_op = ntohs(TFTP_config.PACKET.HEAD.OP);
pkt_block = ntohs(TFTP_config.PACKET.HEAD.BLOCK);
/* Check source address of received packet */
if (remote_addr.sin_addr.s_addr != TFTP_config.SADDR.sin_addr.s_addr) {
continue;
} /* Endif */
/* Validate source port */
if (ack_block && remote_addr.sin_port != TFTP_config.SADDR.sin_port) {
TFTP_SEND(TFTP_config.SOCK, _tftp_error_tid, remote_addr);
continue;
} /* Endif */
/* Check size of received packet */
if (pkt_size < sizeof(TFTP_HEADER)) {
TFTP_SEND(TFTP_config.SOCK, _tftp_error_op, remote_addr);
*size = RTCSERR_TFTP_ERROR + TFTPERR_ILLEGAL_OP;
TFTP_close();
return NULL;
} /* Endif */
/* Check for error packet */
if (pkt_op == TFTPOP_ERROR) {
*size = RTCSERR_TFTP_ERROR + pkt_block;
TFTP_close();
return NULL;
} /* Endif */
/* Check for data packet */
if ((pkt_op != TFTPOP_DATA)
|| (pkt_size > sizeof(TFTP_PACKET))
|| (pkt_block < ack_block)
|| (pkt_block > ack_block+1)) {
TFTP_SEND(TFTP_config.SOCK, _tftp_error_op, remote_addr);
*size = RTCSERR_TFTP_ERROR + TFTPERR_ILLEGAL_OP;
TFTP_close();
return NULL;
} /* Endif */
/* Check for retransmitted packet */
if (pkt_block == ack_block) {
TFTP_timeout_restart(&TFTP_config.TIMEOUT);
TFTP_SEND(TFTP_config.SOCK, TFTP_config.ACK, TFTP_config.SADDR);
continue;
} /* Endif */
/* We have the next packet */
break;
} /* Endfor */
/* Update the adaptive timeout */
TFTP_timeout_update(&TFTP_config.TIMEOUT);
/* Free the original RRQ */
if (!ack_block) {
TFTP_config.SADDR.sin_port = remote_addr.sin_port;
_mem_free(TFTP_config.RRQ_PTR);
TFTP_config.RRQ_PTR = NULL;
} /* Endif */
/* ACK it */
ack_block++;
htons(TFTP_config.ACK.BLOCK, ack_block);
TFTP_SEND(TFTP_config.SOCK, TFTP_config.ACK, TFTP_config.SADDR);
TFTP_config.LAST = (pkt_size < sizeof(TFTP_PACKET));
/* Return the data */
*size = pkt_size - sizeof(TFTP_HEADER);
return TFTP_config.PACKET.DATA;
} /* Endbody */
unsigned char *TFTP_read
(
uint32_t *size
/* [OUT] number of bytes read, or error code */
)
{ /* Body */
uint32_t sock;
sockaddr_in remote_addr;
uint16_t remote_size;
uint16_t ack_block;
uint16_t pkt_op, pkt_block;
uint32_t pkt_size;
uint32_t time_left;
bool expired;
#if TFTP_TIMEOUT_RETRIES
uint32_t retries = 0;
#endif
ack_block = mqx_ntohs(TFTP_config.ACK.BLOCK);
TFTP_timeout_restart(&TFTP_config.TIMEOUT);
for (;;) {
/* Check for timeout */
time_left = TFTP_timeout_left(&TFTP_config.TIMEOUT, &expired);
if (expired) {
#if TFTP_TIMEOUT_RETRIES
retries++;
if (retries > TFTP_TIMEOUT_RETRIES) {
*size = RTCSERR_TFTP_TIMEOUT;
TFTP_close();
return NULL;
} /* Endif */
#endif
/* Retransmit the last packet */
TFTP_RESEND();
} /* Endif */
/* Wait for a packet */
sock = TFTP_WAIT(time_left);
/* Timeout -- retransmit last packet */
if (sock != TFTP_config.SOCK) {
continue;
} /* Endif */
remote_size = sizeof(remote_addr);
pkt_size = TFTP_RECV(TFTP_config.PACKET);
pkt_op = mqx_ntohs(TFTP_config.PACKET.HEAD.OP);
pkt_block = mqx_ntohs(TFTP_config.PACKET.HEAD.BLOCK);
/* Check source address of received packet */
if (remote_addr.sin_addr.s_addr != TFTP_config.SADDR.sin_addr.s_addr) {
continue;
} /* Endif */
/* Validate source port */
if (ack_block && remote_addr.sin_port != TFTP_config.SADDR.sin_port) {
TFTP_SEND(TFTP_config.SOCK, _tftp_error_tid, remote_addr);
continue;
} /* Endif */
/* Check size of received packet */
if (pkt_size < sizeof(TFTP_HEADER)) {
TFTP_SEND(TFTP_config.SOCK, _tftp_error_op, remote_addr);
*size = RTCSERR_TFTP_ERROR + TFTPERR_ILLEGAL_OP;
TFTP_close();
return NULL;
} /* Endif */
/* Check for error packet */
if (pkt_op == TFTPOP_ERROR) {
*size = RTCSERR_TFTP_ERROR + pkt_block;
TFTP_close();
return NULL;
} /* Endif */
/* Check for data packet */
if ((pkt_op != TFTPOP_DATA)
|| (pkt_size > sizeof(TFTP_PACKET))) {
TFTP_SEND(TFTP_config.SOCK, _tftp_error_op, remote_addr);
*size = RTCSERR_TFTP_ERROR + TFTPERR_ILLEGAL_OP;
TFTP_close();
return NULL;
} /* Endif */
/* Check for retransmitted packet */
if (pkt_block == ack_block) {
TFTP_timeout_restart(&TFTP_config.TIMEOUT);
TFTP_SEND(TFTP_config.SOCK, TFTP_config.ACK, TFTP_config.SADDR);
continue;
} /* Endif */
/* Aknowledge also packets with lower id, some servers do retransmit them until they get an ack */
if (pkt_block < ack_block) {
TFTP_timeout_restart(&TFTP_config.TIMEOUT);
mqx_htons(TFTP_config.ACK.BLOCK, pkt_block);
TFTP_SEND(TFTP_config.SOCK, TFTP_config.ACK, TFTP_config.SADDR);
mqx_htons(TFTP_config.ACK.BLOCK, ack_block); /* Restore id of last acknowledged packet */
continue;
} /* Endif */
/* Drop unexpected packets */
if (pkt_block > ack_block+1) {
/* Some server do send more than one packet at a time, these will eventually retransmitted */
continue;
}
/* We have the next packet */
break;
} /* Endfor */
/* Update the adaptive timeout */
TFTP_timeout_update(&TFTP_config.TIMEOUT);
/* Free the original RRQ */
if (!ack_block) {
TFTP_config.SADDR.sin_port = remote_addr.sin_port;
_mem_free(TFTP_config.RRQ_PTR);
TFTP_config.RRQ_PTR = NULL;
} /* Endif */
/* ACK it */
ack_block++;
mqx_htons(TFTP_config.ACK.BLOCK, ack_block);
TFTP_SEND(TFTP_config.SOCK, TFTP_config.ACK, TFTP_config.SADDR);
TFTP_config.LAST = (pkt_size < sizeof(TFTP_PACKET));
/* Return the data */
*size = pkt_size - sizeof(TFTP_HEADER);
return TFTP_config.PACKET.DATA;
} /* Endbody */
