📄 tftp_client.c
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freeaddrinfo(res);
return -1;
}
//
// Read a file from a host into a local buffer. Returns the
// number of bytes actually read, or (-1) if an error occurs.
// On error, *err will hold the reason.
//
// Depreciated. Use tftp_client_get instead.
int
tftp_get(char *filename,
struct sockaddr_in *server,
char *buf,
int len,
int mode,
int *err)
{
char server_name[20];
char *ret;
int port;
ret = inet_ntop(AF_INET, (void *)&server->sin_addr,
server_name, sizeof(server_name));
if (NULL == ret) {
*err = TFTP_NETERR;
return -1;
}
port = server->sin_port;
return tftp_client_get(filename, server_name, port, buf, len, mode, err);
}
//
// Send data to a file on a server via TFTP.
//
int
tftp_put(char *filename,
struct sockaddr_in *server,
char *buf,
int len,
int mode,
int *err)
{
char server_name[20];
char *ret;
int port;
ret = inet_ntop(AF_INET, (void *)&server->sin_addr,
server_name, sizeof(server_name));
if (NULL == ret) {
*err = TFTP_NETERR;
return -1;
}
port = server->sin_port;
return tftp_client_put(filename, server_name, port, buf, len, mode, err);
}
//
// Put a file to a host from a local buffer. Returns the
// number of bytes actually writen, or (-1) if an error occurs.
// On error, *err will hold the reason.
// This version uses the server name. This can be a name for DNS lookup
// or a dotty or colony number format for IPv4 or IPv6.
int tftp_client_put(char *filename,
char *server,
int port,
char *buf,
int len,
int mode,
int *err) {
int result = 0;
int s = -1, actual_len, data_len, recv_len, from_len;
static int put_port = 7800;
struct sockaddr local_addr, from_addr;
char data[SEGSIZE+sizeof(struct tftphdr)];
struct tftphdr *hdr = (struct tftphdr *)data;
char *cp, *fp, *sfp;
struct timeval timeout;
unsigned short last_good_block = 0;
fd_set fds;
int total_timeouts = 0;
struct addrinfo hints;
struct addrinfo * addrinfo;
struct addrinfo * res;
int error;
*err = 0; // Just in case
memset(&hints,0,sizeof(hints));
hints.ai_family = PF_UNSPEC;
error = getaddrinfo(server, "tftp", &hints, &res);
if (error) {
*err = TFTP_NETERR;
return -1;
}
addrinfo = res;
while (addrinfo) {
s = socket(addrinfo->ai_family, addrinfo->ai_socktype,
addrinfo->ai_protocol);
if (s >= 0) {
memcpy(&local_addr,addrinfo->ai_addr,addrinfo->ai_addrlen);
switch(addrinfo->ai_addr->sa_family) {
case AF_INET: {
struct sockaddr_in * saddr =
(struct sockaddr_in *) addrinfo->ai_addr;
struct sockaddr_in * laddr =
(struct sockaddr_in *) &local_addr;
if (port) {
saddr->sin_port = htons(port);
}
laddr->sin_port = htons(put_port++);
laddr->sin_addr.s_addr = INADDR_ANY;
break;
}
#ifdef CYGPKG_NET_INET6
case AF_INET6: {
struct sockaddr_in6 * saddr =
(struct sockaddr_in6 *) addrinfo->ai_addr;
struct sockaddr_in6 * laddr =
(struct sockaddr_in6 *) &local_addr;
if (port) {
saddr->sin6_port = htons(port);
}
laddr->sin6_port = htons(put_port++);
laddr->sin6_addr = in6addr_any;
break;
}
#endif
default:
*err = TFTP_NETERR;
goto out;
}
if (bind(s,
(struct sockaddr *)&local_addr,
addrinfo->ai_addrlen) < 0) {
// Problem setting up my end
*err = TFTP_NETERR;
goto out;
}
while (1) {
// Create initial request
hdr->th_opcode = htons(WRQ); // Create/write file
cp = (char *)&hdr->th_stuff;
fp = filename;
while (*fp) *cp++ = *fp++;
*cp++ = '\0';
if (mode == TFTP_NETASCII) {
fp = "NETASCII";
} else if (mode == TFTP_OCTET) {
fp = "OCTET";
} else {
*err = TFTP_INVALID;
goto out;
}
while (*fp) *cp++ = *fp++;
*cp++ = '\0';
// Send request
if (sendto(s, data, (int)(cp-data), 0,
addrinfo->ai_addr,
addrinfo->ai_addrlen) < 0) {
// Problem sending request
*err = TFTP_NETERR;
goto nextaddr;
}
// Wait for ACK
timeout.tv_sec = TFTP_TIMEOUT_PERIOD;
timeout.tv_usec = 0;
FD_ZERO(&fds);
FD_SET(s, &fds);
if (select(s+1, &fds, 0, 0, &timeout) <= 0) {
if (++total_timeouts > TFTP_RETRIES_MAX) {
// Timeout - no ACK received
*err = TFTP_TIMEOUT;
goto nextaddr;
}
} else {
recv_len = sizeof(data);
from_len = sizeof(from_addr);
if ((data_len = recvfrom(s, &data, recv_len, 0,
&from_addr, &from_len)) < 0) {
// What happened?
*err = TFTP_NETERR;
goto out;
}
if (ntohs(hdr->th_opcode) == ACK) {
// Write request accepted - start sending data
break;
} else
if (ntohs(hdr->th_opcode) == ERROR) {
*err = ntohs(hdr->th_code);
goto out;
} else {
// What kind of packet is this?
goto out;
}
}
}
// Send data
sfp = buf;
last_good_block = 1;
while (result < len) {
// Build packet of data to send
data_len = min(SEGSIZE, len-result);
hdr->th_opcode = htons(DATA);
hdr->th_block = htons(last_good_block);
cp = hdr->th_data;
fp = sfp;
actual_len = data_len + 4;
// FIXME - what about "netascii" data?
while (data_len-- > 0) *cp++ = *fp++;
// Send data packet
if (sendto(s, data, actual_len, 0,
&from_addr, from_len) < 0) {
// Problem sending request
*err = TFTP_NETERR;
goto out;
}
// Wait for ACK
timeout.tv_sec = TFTP_TIMEOUT_PERIOD;
timeout.tv_usec = 0;
FD_ZERO(&fds);
FD_SET(s, &fds);
if (select(s+1, &fds, 0, 0, &timeout) <= 0) {
if (++total_timeouts > TFTP_TIMEOUT_MAX) {
// Timeout - no data received
*err = TFTP_TIMEOUT;
goto out;
}
} else {
recv_len = sizeof(data);
from_len = sizeof(from_addr);
if ((data_len = recvfrom(s, &data, recv_len, 0,
&from_addr, &from_len)) < 0) {
// What happened?
*err = TFTP_NETERR;
goto out;
}
if (ntohs(hdr->th_opcode) == ACK) {
if (ntohs(hdr->th_block) == last_good_block) {
// Advance pointers, etc
sfp = fp;
result += (actual_len - 4);
last_good_block++;
} else {
diag_printf("Send block #%d, got ACK for #%d\n",
last_good_block, ntohs(hdr->th_block));
}
} else
if (ntohs(hdr->th_opcode) == ERROR) {
*err = ntohs(hdr->th_code);
goto out;
} else {
// What kind of packet is this?
*err = TFTP_PROTOCOL;
goto out;
}
}
}
close (s);
return result;
}
// If we got here, it means there was a problem connecting to the
// server. Try the next address returned by getaddrinfo
nextaddr:
if (-1 != s) {
close(s);
}
addrinfo=addrinfo->ai_next;
}
// We ran into problems. Cleanup
out:
if (-1 != s) {
close (s);
}
freeaddrinfo(res);
return -1;
}
// EOF tftp_client.c
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