static int
tftp_ack(int *err)
{
struct tftphdr *hdr = (struct tftphdr *)tftp_stream.data;
// ACK last packet so server can shut down
if (tftp_stream.packets_received > 0) {
hdr->th_opcode = htons(ACK);
hdr->th_block = htons((cyg_uint16)tftp_stream.last_good_block & 0xFFFF);
if (__udp_sendto(tftp_stream.data, 4 /* FIXME */,
&tftp_stream.from_addr, &tftp_stream.local_addr) < 0) {
// Problem sending ACK
*err = TFTP_NETERR;
return -1;
}
}
return 0;
}
/* Send the query to the server and read the response back. Return -1
if it fails, otherwise put the response back in msg and return the
length of the response. */
static int
send_recv(char * msg, int len, int msglen)
{
struct dns_header *dns_hdr;
int finished = false;
int read = 0;
dns_hdr = (struct dns_header *) msg;
do {
int len_togo = len;
struct timeval timeout;
struct sockaddr_in local_addr, from_addr;
memset((char *)&local_addr, 0, sizeof(local_addr));
local_addr.sin_family = AF_INET;
local_addr.sin_addr.s_addr = htonl(INADDR_ANY);
local_addr.sin_port = htons(get_port++);
if (__udp_sendto(msg, len_togo, &server, &local_addr) < 0)
return -1;
memset((char *)&from_addr, 0, sizeof(from_addr));
timeout.tv_sec = CYGNUM_REDBOOT_NETWORKING_DNS_TIMEOUT;
timeout.tv_usec = 0;
read = __udp_recvfrom(msg, len, &from_addr, &local_addr, &timeout);
if (read < 0)
return -1;
/* Reply to an old query. Ignore it */
if (ntohs(dns_hdr->id) != (id-1)) {
continue;
}
finished = true;
} while (!finished);
return read;
}
int
tftp_stream_open(connection_info_t *info,
int *err)
{
struct tftphdr *hdr = (struct tftphdr *)tftp_stream.data;
char *cp, *fp;
char test_buf;
if (!have_net || tftp_stream.open) {
*err = TFTP_INVALID; // Already open
return -1;
}
// Create initial request
hdr->th_opcode = htons(RRQ); // Read file
cp = (char *)&hdr->th_stuff;
fp = info->filename;
while (*fp) *cp++ = *fp++;
*cp++ = '\0';
// Since this is used for downloading data, OCTET (binary) is the
// only mode that makes sense.
fp = "OCTET";
while (*fp) *cp++ = *fp++;
*cp++ = '\0';
memset((char *)&tftp_stream.local_addr, 0, sizeof(tftp_stream.local_addr));
tftp_stream.local_addr.sin_family = AF_INET;
tftp_stream.local_addr.sin_addr.s_addr = htonl(INADDR_ANY);
tftp_stream.local_addr.sin_port = htons(get_port++);
if (info->server->sin_port == 0) {
info->server->sin_port = htons(TFTP_PORT);
} else {
info->server->sin_port = htons(info->server->sin_port);
}
// Send request - note: RFC 1350 (TFTP rev 2) indicates that this should be
// only as long as required to hold the request, with the nul terminator.
// Some servers silently go to lunch if the request is not the correct size.
if (__udp_sendto(tftp_stream.data, cp-(char *)hdr,
info->server, &tftp_stream.local_addr) < 0) {
// Problem sending request
*err = TFTP_NETERR;
return -1;
}
tftp_stream.open = true;
tftp_stream.avail = 0;
tftp_stream.actual_len = -1;
tftp_stream.last_good_block = 0;
tftp_stream.total_timeouts = 0;
tftp_stream.from_addr.sin_port = 0;
tftp_stream.packets_received = 0;
// Try and read the first byte [block] since no errors are
// reported until then.
if (tftp_stream_read(&test_buf, 1, err) == 1) {
// Back up [rewind] over this datum
tftp_stream.bufp--;
tftp_stream.avail++;
return 0; // Open and first read successful
} else {
tftp_stream.open = false;
return -1; // Couldn't read
}
}
