branch: master
tftp.c
40262 bytesRaw
/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* SPDX-License-Identifier: curl
*
***************************************************************************/
#include "curl_setup.h"
#include "urldata.h"
#include "tftp.h"
#ifndef CURL_DISABLE_TFTP
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#ifdef HAVE_NET_IF_H
#include <net/if.h>
#endif
#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif
#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#include "cfilters.h"
#include "cf-socket.h"
#include "transfer.h"
#include "sendf.h"
#include "curl_trc.h"
#include "progress.h"
#include "connect.h"
#include "sockaddr.h" /* required for Curl_sockaddr_storage */
#include "url.h"
#include "strcase.h"
#include "select.h"
#include "escape.h"
#include "curlx/strerr.h"
#include "curlx/strparse.h"
#include "curlx/strcopy.h"
/* RFC2348 allows the block size to be negotiated */
#define TFTP_BLKSIZE_DEFAULT 512
#define TFTP_OPTION_BLKSIZE "blksize"
/* from RFC2349: */
#define TFTP_OPTION_TSIZE "tsize"
#define TFTP_OPTION_INTERVAL "timeout"
typedef enum {
TFTP_MODE_NETASCII = 0,
TFTP_MODE_OCTET
} tftp_mode_t;
typedef enum {
TFTP_STATE_START = 0,
TFTP_STATE_RX,
TFTP_STATE_TX,
TFTP_STATE_FIN
} tftp_state_t;
typedef enum {
TFTP_EVENT_NONE = -1,
TFTP_EVENT_INIT = 0,
TFTP_EVENT_RRQ = 1,
TFTP_EVENT_WRQ = 2,
TFTP_EVENT_DATA = 3,
TFTP_EVENT_ACK = 4,
TFTP_EVENT_ERROR = 5,
TFTP_EVENT_OACK = 6,
TFTP_EVENT_TIMEOUT
} tftp_event_t;
typedef enum {
TFTP_ERR_UNDEF = 0,
TFTP_ERR_NOTFOUND,
TFTP_ERR_PERM,
TFTP_ERR_DISKFULL,
TFTP_ERR_ILLEGAL,
TFTP_ERR_UNKNOWNID,
TFTP_ERR_EXISTS,
TFTP_ERR_NOSUCHUSER, /* This will never be triggered by this code */
/* The remaining error codes are internal to curl */
TFTP_ERR_NONE = -100,
TFTP_ERR_TIMEOUT,
TFTP_ERR_NORESPONSE
} tftp_error_t;
struct tftp_packet {
unsigned char *data;
};
/* meta key for storing protocol meta at connection */
#define CURL_META_TFTP_CONN "meta:proto:tftp:conn"
struct tftp_conn {
struct Curl_sockaddr_storage local_addr;
struct Curl_sockaddr_storage remote_addr;
struct tftp_packet rpacket;
struct tftp_packet spacket;
tftp_state_t state;
tftp_mode_t mode;
tftp_error_t error;
tftp_event_t event;
struct Curl_easy *data;
curl_socket_t sockfd;
int retries;
int retry_time;
int retry_max;
time_t rx_time;
curl_socklen_t remote_addrlen;
int rbytes;
size_t sbytes;
unsigned int blksize;
unsigned int requested_blksize;
unsigned short block;
BIT(remote_pinned);
};
/**********************************************************
*
* tftp_set_timeouts -
*
* Set timeouts based on state machine state.
* Use user provided connect timeouts until DATA or ACK
* packet is received, then use user-provided transfer timeouts
*
*
**********************************************************/
static CURLcode tftp_set_timeouts(struct tftp_conn *state)
{
time_t timeout;
timediff_t timeout_ms;
/* Compute drop-dead time */
timeout_ms = Curl_timeleft_ms(state->data);
if(timeout_ms < 0) {
/* time-out, bail out, go home */
failf(state->data, "Connection time-out");
return CURLE_OPERATION_TIMEDOUT;
}
/* Set per-block timeout to total */
if(timeout_ms > 0)
timeout = (time_t)(timeout_ms + 500) / 1000;
else
timeout = 15;
/* Average reposting an ACK after 5 seconds */
state->retry_max = (int)timeout / 5;
/* Bound the total number */
if(state->retry_max < 3)
state->retry_max = 3;
if(state->retry_max > 50)
state->retry_max = 50;
/* Compute the re-ACK interval to suit the timeout */
state->retry_time = (int)(timeout / state->retry_max);
if(state->retry_time < 1)
state->retry_time = 1;
infof(state->data,
"set timeouts for state %d; Total %" FMT_OFF_T ", retry %d maxtry %d",
(int)state->state, timeout_ms, state->retry_time, state->retry_max);
/* init RX time */
state->rx_time = time(NULL);
return CURLE_OK;
}
/**********************************************************
*
* tftp_set_send_first
*
* Event handler for the START state
*
**********************************************************/
static void setpacketevent(struct tftp_packet *packet, unsigned short num)
{
packet->data[0] = (unsigned char)(num >> 8);
packet->data[1] = (unsigned char)(num & 0xff);
}
static void setpacketblock(struct tftp_packet *packet, unsigned short num)
{
packet->data[2] = (unsigned char)(num >> 8);
packet->data[3] = (unsigned char)(num & 0xff);
}
static unsigned short getrpacketevent(const struct tftp_packet *packet)
{
return (unsigned short)((packet->data[0] << 8) | packet->data[1]);
}
static unsigned short getrpacketblock(const struct tftp_packet *packet)
{
return (unsigned short)((packet->data[2] << 8) | packet->data[3]);
}
static size_t tftp_strnlen(const char *string, size_t maxlen)
{
const char *end = memchr(string, '\0', maxlen);
return end ? (size_t)(end - string) : maxlen;
}
static const char *tftp_option_get(const char *buf, size_t len,
const char **option, const char **value)
{
size_t loc;
loc = tftp_strnlen(buf, len);
loc++; /* NULL term */
if(loc >= len)
return NULL;
*option = buf;
loc += tftp_strnlen(buf + loc, len - loc);
loc++; /* NULL term */
if(loc > len)
return NULL;
*value = &buf[strlen(*option) + 1];
return &buf[loc];
}
static CURLcode tftp_parse_option_ack(struct tftp_conn *state,
const char *ptr, int len)
{
const char *tmp = ptr;
struct Curl_easy *data = state->data;
/* if OACK does not contain blksize option, the default (512) must be used */
state->blksize = TFTP_BLKSIZE_DEFAULT;
while(tmp < ptr + len) {
const char *option, *value;
tmp = tftp_option_get(tmp, ptr + len - tmp, &option, &value);
if(!tmp) {
failf(data, "Malformed ACK packet, rejecting");
return CURLE_TFTP_ILLEGAL;
}
infof(data, "got option=(%s) value=(%s)", option, value);
if(checkprefix(TFTP_OPTION_BLKSIZE, option)) {
curl_off_t blksize;
if(curlx_str_number(&value, &blksize, TFTP_BLKSIZE_MAX)) {
failf(data, "%s (%d)", "blksize is larger than max supported",
TFTP_BLKSIZE_MAX);
return CURLE_TFTP_ILLEGAL;
}
if(!blksize) {
failf(data, "invalid blocksize value in OACK packet");
return CURLE_TFTP_ILLEGAL;
}
else if(blksize < TFTP_BLKSIZE_MIN) {
failf(data, "%s (%d)", "blksize is smaller than min supported",
TFTP_BLKSIZE_MIN);
return CURLE_TFTP_ILLEGAL;
}
else if(blksize > state->requested_blksize) {
/* could realloc pkt buffers here, but the spec does not call out
* support for the server requesting a bigger blksize than the client
* requests */
failf(data, "server requested blksize larger than allocated (%"
CURL_FORMAT_CURL_OFF_T ")", blksize);
return CURLE_TFTP_ILLEGAL;
}
state->blksize = (int)blksize;
infof(data, "blksize parsed from OACK (%d) requested (%d)",
state->blksize, state->requested_blksize);
}
else if(checkprefix(TFTP_OPTION_TSIZE, option)) {
curl_off_t tsize = 0;
/* tsize should be ignored on upload: Who cares about the size of the
remote file? */
if(!data->state.upload &&
!curlx_str_number(&value, &tsize, CURL_OFF_T_MAX)) {
if(!tsize) {
failf(data, "invalid tsize -:%s:- value in OACK packet", value);
return CURLE_TFTP_ILLEGAL;
}
infof(data, "tsize parsed from OACK (%" CURL_FORMAT_CURL_OFF_T ")",
tsize);
Curl_pgrsSetDownloadSize(data, tsize);
}
}
}
return CURLE_OK;
}
static CURLcode tftp_option_add(struct tftp_conn *state, size_t *csize,
size_t index, const char *option)
{
char *buf = (char *)&state->spacket.data[index];
size_t oplen = strlen(option);
size_t blen;
if((state->blksize <= index) ||
(oplen + 1) > (size_t)(state->blksize - index))
return CURLE_TFTP_ILLEGAL;
blen = state->blksize - index;
curlx_strcopy(buf, blen, option, oplen);
*csize += oplen + 1;
return CURLE_OK;
}
/* the next blocknum is x + 1 but it needs to wrap at an unsigned 16-bit
boundary */
#define NEXT_BLOCKNUM(x) (((x) + 1) & 0xffff)
/**********************************************************
*
* tftp_tx
*
* Event handler for the TX state
*
**********************************************************/
static CURLcode tftp_tx(struct tftp_conn *state, tftp_event_t event)
{
struct Curl_easy *data = state->data;
ssize_t sbytes;
CURLcode result = CURLE_OK;
struct SingleRequest *k = &data->req;
size_t cb; /* Bytes currently read */
char buffer[STRERROR_LEN];
char *bufptr;
bool eos;
switch(event) {
case TFTP_EVENT_ACK:
case TFTP_EVENT_OACK:
if(event == TFTP_EVENT_ACK) {
/* Ack the packet */
int rblock = getrpacketblock(&state->rpacket);
if(rblock != state->block &&
/* There is a bug in tftpd-hpa that causes it to send us an ACK for
* 65535 when the block number wraps to 0. To handle it, when we are
* expecting 0, also accept 65535. See
* https://www.syslinux.org/archives/2010-September/015612.html
* */
!(state->block == 0 && rblock == 65535)) {
/* This is not the expected block. Log it and up the retry counter */
infof(data, "Received ACK for block %d, expecting %d",
rblock, state->block);
state->retries++;
/* Bail out if over the maximum */
if(state->retries > state->retry_max) {
failf(data, "tftp_tx: giving up waiting for block %d ack",
state->block);
result = CURLE_SEND_ERROR;
}
else {
/* Re-send the data packet */
sbytes = sendto(state->sockfd, (void *)state->spacket.data,
4 + (SEND_TYPE_ARG3)state->sbytes, SEND_4TH_ARG,
(struct sockaddr *)&state->remote_addr,
state->remote_addrlen);
/* Check all sbytes were sent */
if(sbytes < 0) {
failf(data, "%s",
curlx_strerror(SOCKERRNO, buffer, sizeof(buffer)));
result = CURLE_SEND_ERROR;
}
}
return result;
}
/* This is the expected packet. Reset the counters and send the next
block */
state->rx_time = time(NULL);
state->block++;
}
else
state->block = 1; /* first data block is 1 when using OACK */
state->retries = 0;
setpacketevent(&state->spacket, TFTP_EVENT_DATA);
setpacketblock(&state->spacket, state->block);
if(state->block > 1 && state->sbytes < state->blksize) {
state->state = TFTP_STATE_FIN;
return CURLE_OK;
}
/* TFTP considers data block size < 512 bytes as an end of session, so
* in some cases we must wait for additional data to build full (512 bytes)
* data block.
* */
state->sbytes = 0;
bufptr = (char *)state->spacket.data + 4;
do {
result = Curl_client_read(data, bufptr, state->blksize - state->sbytes,
&cb, &eos);
if(result)
return result;
state->sbytes += cb;
bufptr += cb;
} while(state->sbytes < state->blksize && cb);
sbytes = sendto(state->sockfd, (void *)state->spacket.data,
4 + (SEND_TYPE_ARG3)state->sbytes, SEND_4TH_ARG,
(struct sockaddr *)&state->remote_addr,
state->remote_addrlen);
/* Check all sbytes were sent */
if(sbytes < 0) {
failf(data, "%s", curlx_strerror(SOCKERRNO, buffer, sizeof(buffer)));
return CURLE_SEND_ERROR;
}
/* Update the progress meter */
k->writebytecount += state->sbytes;
Curl_pgrs_upload_inc(data, state->sbytes);
break;
case TFTP_EVENT_TIMEOUT:
/* Increment the retry counter and log the timeout */
state->retries++;
infof(data, "Timeout waiting for block %d ACK. "
"Retries = %d", NEXT_BLOCKNUM(state->block), state->retries);
/* Decide if we have had enough */
if(state->retries > state->retry_max) {
state->error = TFTP_ERR_TIMEOUT;
state->state = TFTP_STATE_FIN;
}
else {
/* Re-send the data packet */
sbytes = sendto(state->sockfd, (void *)state->spacket.data,
4 + (SEND_TYPE_ARG3)state->sbytes, SEND_4TH_ARG,
(struct sockaddr *)&state->remote_addr,
state->remote_addrlen);
/* Check all sbytes were sent */
if(sbytes < 0) {
failf(data, "%s", curlx_strerror(SOCKERRNO, buffer, sizeof(buffer)));
return CURLE_SEND_ERROR;
}
/* since this was a re-send, we remain at the still byte position */
Curl_pgrsSetUploadCounter(data, k->writebytecount);
}
break;
case TFTP_EVENT_ERROR:
state->state = TFTP_STATE_FIN;
setpacketevent(&state->spacket, TFTP_EVENT_ERROR);
setpacketblock(&state->spacket, state->block);
(void)sendto(state->sockfd, (void *)state->spacket.data, 4, SEND_4TH_ARG,
(struct sockaddr *)&state->remote_addr,
state->remote_addrlen);
/* do not bother with the return code, but if the socket is still up we
* should be a good TFTP client and let the server know we are done */
state->state = TFTP_STATE_FIN;
break;
default:
failf(data, "tftp_tx: internal error, event: %i", (int)event);
break;
}
return result;
}
static CURLcode tftp_connect_for_tx(struct tftp_conn *state,
tftp_event_t event)
{
CURLcode result;
infof(state->data, "%s", "Connected for transmit");
state->state = TFTP_STATE_TX;
result = tftp_set_timeouts(state);
if(result)
return result;
return tftp_tx(state, event);
}
/**********************************************************
*
* tftp_rx
*
* Event handler for the RX state
*
**********************************************************/
static CURLcode tftp_rx(struct tftp_conn *state, tftp_event_t event)
{
ssize_t sbytes;
int rblock;
struct Curl_easy *data = state->data;
char buffer[STRERROR_LEN];
switch(event) {
case TFTP_EVENT_DATA:
/* Is this the block we expect? */
rblock = getrpacketblock(&state->rpacket);
if(NEXT_BLOCKNUM(state->block) == rblock) {
/* This is the expected block. Reset counters and ACK it. */
state->retries = 0;
}
else if(state->block == rblock) {
/* This is the last recently received block again. Log it and ACK it
again. */
infof(data, "Received last DATA packet block %d again.", rblock);
}
else {
/* totally unexpected, log it */
infof(data,
"Received unexpected DATA packet block %d, expecting block %d",
rblock, NEXT_BLOCKNUM(state->block));
break;
}
/* ACK this block. */
state->block = (unsigned short)rblock;
setpacketevent(&state->spacket, TFTP_EVENT_ACK);
setpacketblock(&state->spacket, state->block);
sbytes = sendto(state->sockfd, (void *)state->spacket.data,
4, SEND_4TH_ARG,
(struct sockaddr *)&state->remote_addr,
state->remote_addrlen);
if(sbytes < 0) {
failf(data, "%s", curlx_strerror(SOCKERRNO, buffer, sizeof(buffer)));
return CURLE_SEND_ERROR;
}
/* Check if completed (That is, a less than full packet is received) */
if(state->rbytes < (ssize_t)state->blksize + 4) {
state->state = TFTP_STATE_FIN;
}
else {
state->state = TFTP_STATE_RX;
}
state->rx_time = time(NULL);
break;
case TFTP_EVENT_OACK:
/* ACK option acknowledgement so we can move on to data */
state->block = 0;
state->retries = 0;
setpacketevent(&state->spacket, TFTP_EVENT_ACK);
setpacketblock(&state->spacket, state->block);
sbytes = sendto(state->sockfd, (void *)state->spacket.data,
4, SEND_4TH_ARG,
(struct sockaddr *)&state->remote_addr,
state->remote_addrlen);
if(sbytes < 0) {
failf(data, "%s", curlx_strerror(SOCKERRNO, buffer, sizeof(buffer)));
return CURLE_SEND_ERROR;
}
/* we are ready to RX data */
state->state = TFTP_STATE_RX;
state->rx_time = time(NULL);
break;
case TFTP_EVENT_TIMEOUT:
/* Increment the retry count and fail if over the limit */
state->retries++;
infof(data,
"Timeout waiting for block %d ACK. Retries = %d",
NEXT_BLOCKNUM(state->block), state->retries);
if(state->retries > state->retry_max) {
state->error = TFTP_ERR_TIMEOUT;
state->state = TFTP_STATE_FIN;
}
else {
/* Resend the previous ACK */
sbytes = sendto(state->sockfd, (void *)state->spacket.data,
4, SEND_4TH_ARG,
(struct sockaddr *)&state->remote_addr,
state->remote_addrlen);
if(sbytes < 0) {
failf(data, "%s", curlx_strerror(SOCKERRNO, buffer, sizeof(buffer)));
return CURLE_SEND_ERROR;
}
}
break;
case TFTP_EVENT_ERROR:
setpacketevent(&state->spacket, TFTP_EVENT_ERROR);
setpacketblock(&state->spacket, state->block);
(void)sendto(state->sockfd, (void *)state->spacket.data,
4, SEND_4TH_ARG,
(struct sockaddr *)&state->remote_addr,
state->remote_addrlen);
/* do not bother with the return code, but if the socket is still up we
* should be a good TFTP client and let the server know we are done */
state->state = TFTP_STATE_FIN;
break;
default:
failf(data, "%s", "tftp_rx: internal error");
return CURLE_TFTP_ILLEGAL; /* not really the perfect return code for
this */
}
return CURLE_OK;
}
static CURLcode tftp_connect_for_rx(struct tftp_conn *state,
tftp_event_t event)
{
CURLcode result;
infof(state->data, "%s", "Connected for receive");
state->state = TFTP_STATE_RX;
result = tftp_set_timeouts(state);
if(result)
return result;
return tftp_rx(state, event);
}
static CURLcode tftp_send_first(struct tftp_conn *state,
tftp_event_t event)
{
size_t sbytes;
ssize_t senddata;
const char *mode = "octet";
char *filename;
struct Curl_easy *data = state->data;
const struct Curl_sockaddr_ex *remote_addr = NULL;
CURLcode result = CURLE_OK;
/* Set ASCII mode if -B flag was used */
if(data->state.prefer_ascii)
mode = "netascii";
switch(event) {
case TFTP_EVENT_INIT: /* Send the first packet out */
case TFTP_EVENT_TIMEOUT: /* Resend the first packet out */
/* Increment the retry counter, quit if over the limit */
state->retries++;
if(state->retries > state->retry_max) {
state->error = TFTP_ERR_NORESPONSE;
state->state = TFTP_STATE_FIN;
return result;
}
if(data->state.upload) {
/* If we are uploading, send an WRQ */
setpacketevent(&state->spacket, TFTP_EVENT_WRQ);
if(data->state.infilesize != -1)
Curl_pgrsSetUploadSize(data, data->state.infilesize);
}
else {
/* If we are downloading, send an RRQ */
setpacketevent(&state->spacket, TFTP_EVENT_RRQ);
}
/* As RFC3617 describes the separator slash is not actually part of the
filename so we skip the always-present first letter of the path
string. */
if(!state->data->state.up.path[1]) {
failf(data, "Missing filename");
return CURLE_TFTP_ILLEGAL;
}
result = Curl_urldecode(&state->data->state.up.path[1], 0,
&filename, NULL, REJECT_ZERO);
if(result)
return result;
if(strlen(filename) + strlen(mode) + 4 > state->blksize) {
failf(data, "TFTP filename too long");
curlx_free(filename);
return CURLE_TFTP_ILLEGAL; /* too long filename field */
}
sbytes = 2 +
curl_msnprintf((char *)state->spacket.data + 2,
state->blksize,
"%s%c%s%c", filename, '\0', mode, '\0');
curlx_free(filename);
/* optional addition of TFTP options */
if(!data->set.tftp_no_options) {
char buf[64];
/* add tsize option */
curl_msnprintf(buf, sizeof(buf), "%" FMT_OFF_T,
data->state.upload && (data->state.infilesize != -1) ?
data->state.infilesize : 0);
result = tftp_option_add(state, &sbytes, sbytes, TFTP_OPTION_TSIZE);
if(result == CURLE_OK)
result = tftp_option_add(state, &sbytes, sbytes, buf);
/* add blksize option */
curl_msnprintf(buf, sizeof(buf), "%d", state->requested_blksize);
if(result == CURLE_OK)
result = tftp_option_add(state, &sbytes, sbytes, TFTP_OPTION_BLKSIZE);
if(result == CURLE_OK)
result = tftp_option_add(state, &sbytes, sbytes, buf);
/* add timeout option */
curl_msnprintf(buf, sizeof(buf), "%d", state->retry_time);
if(result == CURLE_OK)
result = tftp_option_add(state, &sbytes, sbytes, TFTP_OPTION_INTERVAL);
if(result == CURLE_OK)
result = tftp_option_add(state, &sbytes, sbytes, buf);
if(result != CURLE_OK) {
failf(data, "TFTP buffer too small for options");
return CURLE_TFTP_ILLEGAL;
}
}
/* the typecase for the 3rd argument is mostly for systems that do
not have a size_t argument, like older unixes that want an 'int' */
#ifdef __AMIGA__
#define CURL_SENDTO_ARG5(x) CURL_UNCONST(x)
#else
#define CURL_SENDTO_ARG5(x) (x)
#endif
remote_addr = Curl_conn_get_remote_addr(data, FIRSTSOCKET);
if(!remote_addr)
return CURLE_FAILED_INIT;
senddata = sendto(state->sockfd, (void *)state->spacket.data,
(SEND_TYPE_ARG3)sbytes, 0,
CURL_SENDTO_ARG5(&remote_addr->curl_sa_addr),
(curl_socklen_t)remote_addr->addrlen);
if(senddata != (ssize_t)sbytes) {
char buffer[STRERROR_LEN];
failf(data, "%s", curlx_strerror(SOCKERRNO, buffer, sizeof(buffer)));
return CURLE_SEND_ERROR;
}
break;
case TFTP_EVENT_OACK:
if(data->state.upload) {
result = tftp_connect_for_tx(state, event);
}
else {
result = tftp_connect_for_rx(state, event);
}
break;
case TFTP_EVENT_ACK: /* Connected for transmit */
result = tftp_connect_for_tx(state, event);
break;
case TFTP_EVENT_DATA: /* Connected for receive */
result = tftp_connect_for_rx(state, event);
break;
case TFTP_EVENT_ERROR:
state->state = TFTP_STATE_FIN;
break;
default:
failf(state->data, "tftp_send_first: internal error");
return CURLE_TFTP_ILLEGAL;
}
return result;
}
/**********************************************************
*
* tftp_translate_code
*
* Translate internal error codes to CURL error codes
*
**********************************************************/
static CURLcode tftp_translate_code(tftp_error_t error)
{
CURLcode result = CURLE_OK;
if(error != TFTP_ERR_NONE) {
switch(error) {
case TFTP_ERR_NOTFOUND:
result = CURLE_TFTP_NOTFOUND;
break;
case TFTP_ERR_PERM:
result = CURLE_TFTP_PERM;
break;
case TFTP_ERR_DISKFULL:
result = CURLE_REMOTE_DISK_FULL;
break;
case TFTP_ERR_UNDEF:
case TFTP_ERR_ILLEGAL:
result = CURLE_TFTP_ILLEGAL;
break;
case TFTP_ERR_UNKNOWNID:
result = CURLE_TFTP_UNKNOWNID;
break;
case TFTP_ERR_EXISTS:
result = CURLE_REMOTE_FILE_EXISTS;
break;
case TFTP_ERR_NOSUCHUSER:
result = CURLE_TFTP_NOSUCHUSER;
break;
case TFTP_ERR_TIMEOUT:
result = CURLE_OPERATION_TIMEDOUT;
break;
case TFTP_ERR_NORESPONSE:
result = CURLE_COULDNT_CONNECT;
break;
default:
result = CURLE_ABORTED_BY_CALLBACK;
break;
}
}
else
result = CURLE_OK;
return result;
}
/**********************************************************
*
* tftp_state_machine
*
* The tftp state machine event dispatcher
*
**********************************************************/
static CURLcode tftp_state_machine(struct tftp_conn *state,
tftp_event_t event)
{
CURLcode result = CURLE_OK;
struct Curl_easy *data = state->data;
switch(state->state) {
case TFTP_STATE_START:
DEBUGF(infof(data, "TFTP_STATE_START"));
result = tftp_send_first(state, event);
break;
case TFTP_STATE_RX:
DEBUGF(infof(data, "TFTP_STATE_RX"));
result = tftp_rx(state, event);
break;
case TFTP_STATE_TX:
DEBUGF(infof(data, "TFTP_STATE_TX"));
result = tftp_tx(state, event);
break;
case TFTP_STATE_FIN:
infof(data, "%s", "TFTP finished");
break;
default:
DEBUGF(infof(data, "STATE: %d", state->state));
failf(data, "%s", "Internal state machine error");
result = CURLE_TFTP_ILLEGAL;
break;
}
return result;
}
static void tftp_conn_dtor(void *key, size_t klen, void *entry)
{
struct tftp_conn *state = entry;
(void)key;
(void)klen;
Curl_safefree(state->rpacket.data);
Curl_safefree(state->spacket.data);
curlx_free(state);
}
/**********************************************************
*
* tftp_connect
*
* The connect callback
*
**********************************************************/
static CURLcode tftp_connect(struct Curl_easy *data, bool *done)
{
struct tftp_conn *state;
int blksize;
int need_blksize;
struct connectdata *conn = data->conn;
const struct Curl_sockaddr_ex *remote_addr = NULL;
CURLcode result;
blksize = TFTP_BLKSIZE_DEFAULT;
state = curlx_calloc(1, sizeof(*state));
if(!state ||
Curl_conn_meta_set(conn, CURL_META_TFTP_CONN, state, tftp_conn_dtor))
return CURLE_OUT_OF_MEMORY;
/* alloc pkt buffers based on specified blksize */
if(data->set.tftp_blksize)
/* range checked when set */
blksize = (int)data->set.tftp_blksize;
need_blksize = blksize;
/* default size is the fallback when no OACK is received */
if(need_blksize < TFTP_BLKSIZE_DEFAULT)
need_blksize = TFTP_BLKSIZE_DEFAULT;
if(!state->rpacket.data) {
state->rpacket.data = curlx_calloc(1, need_blksize + 2 + 2);
if(!state->rpacket.data)
return CURLE_OUT_OF_MEMORY;
}
if(!state->spacket.data) {
state->spacket.data = curlx_calloc(1, need_blksize + 2 + 2);
if(!state->spacket.data)
return CURLE_OUT_OF_MEMORY;
}
/* we do not keep TFTP connections up because there is none or little gain
* for UDP */
connclose(conn, "TFTP");
state->data = data;
state->sockfd = conn->sock[FIRSTSOCKET];
state->state = TFTP_STATE_START;
state->error = TFTP_ERR_NONE;
state->blksize = TFTP_BLKSIZE_DEFAULT; /* Unless updated by OACK response */
state->requested_blksize = blksize;
remote_addr = Curl_conn_get_remote_addr(data, FIRSTSOCKET);
DEBUGASSERT(remote_addr);
if(!remote_addr)
return CURLE_FAILED_INIT;
((struct sockaddr *)&state->local_addr)->sa_family =
(CURL_SA_FAMILY_T)(remote_addr->family);
result = tftp_set_timeouts(state);
if(result)
return result;
if(!conn->bits.bound) {
/* If not already bound, bind to any interface, random UDP port. If it is
* reused or a custom local port was desired, this has already been done!
*
* We once used the size of the local_addr struct as the third argument
* for bind() to better work with IPv6 or whatever size the struct could
* have, but we learned that at least Tru64, AIX and IRIX *requires* the
* size of that argument to match the exact size of a 'sockaddr_in' struct
* when running IPv4-only.
*
* Therefore we use the size from the address we connected to, which we
* assume uses the same IP version and thus hopefully this works for both
* IPv4 and IPv6...
*/
int rc = bind(state->sockfd, (struct sockaddr *)&state->local_addr,
(curl_socklen_t)remote_addr->addrlen);
if(rc) {
char buffer[STRERROR_LEN];
failf(data, "bind() failed; %s",
curlx_strerror(SOCKERRNO, buffer, sizeof(buffer)));
return CURLE_COULDNT_CONNECT;
}
conn->bits.bound = TRUE;
}
Curl_pgrsStartNow(data);
*done = TRUE;
return CURLE_OK;
}
/**********************************************************
*
* tftp_done
*
* The done callback
*
**********************************************************/
static CURLcode tftp_done(struct Curl_easy *data, CURLcode status,
bool premature)
{
CURLcode result = CURLE_OK;
struct connectdata *conn = data->conn;
struct tftp_conn *state = Curl_conn_meta_get(conn, CURL_META_TFTP_CONN);
(void)status;
(void)premature;
if(Curl_pgrsDone(data))
return CURLE_ABORTED_BY_CALLBACK;
/* If we have encountered an error */
if(state)
result = tftp_translate_code(state->error);
return result;
}
static CURLcode tftp_pollset(struct Curl_easy *data,
struct easy_pollset *ps)
{
return Curl_pollset_add_in(data, ps, data->conn->sock[FIRSTSOCKET]);
}
/**********************************************************
*
* tftp_receive_packet
*
* Called once select fires and data is ready on the socket
*
**********************************************************/
static CURLcode tftp_receive_packet(struct Curl_easy *data,
struct tftp_conn *state)
{
CURLcode result = CURLE_OK;
struct Curl_sockaddr_storage remote_addr;
curl_socklen_t fromlen = sizeof(remote_addr);
/* Receive the packet */
state->rbytes = (int)recvfrom(state->sockfd,
(void *)state->rpacket.data,
(RECV_TYPE_ARG3)state->blksize + 4,
0,
(struct sockaddr *)&remote_addr,
&fromlen);
if((state->rbytes >= 0) && fromlen) {
if(state->remote_pinned) {
/* pinned, verify that it comes from the same address */
if((state->remote_addrlen != fromlen) ||
memcmp(&remote_addr, &state->remote_addr, fromlen)) {
failf(data, "Data received from another address");
return CURLE_RECV_ERROR;
}
}
else {
/* pin address on first use */
state->remote_pinned = TRUE;
state->remote_addrlen = fromlen;
memcpy(&state->remote_addr, &remote_addr, fromlen);
}
}
/* Sanity check packet length */
if(state->rbytes < 4) {
failf(data, "Received too short packet");
/* Not a timeout, but how best to handle it? */
state->event = TFTP_EVENT_TIMEOUT;
}
else {
/* The event is given by the TFTP packet time */
unsigned short event = getrpacketevent(&state->rpacket);
state->event = (tftp_event_t)event;
switch(state->event) {
case TFTP_EVENT_DATA:
/* Do not pass to the client empty or retransmitted packets */
if(state->rbytes > 4 &&
(NEXT_BLOCKNUM(state->block) == getrpacketblock(&state->rpacket))) {
result = Curl_client_write(data, CLIENTWRITE_BODY,
(const char *)state->rpacket.data + 4,
state->rbytes - 4);
if(result) {
tftp_state_machine(state, TFTP_EVENT_ERROR);
return result;
}
}
break;
case TFTP_EVENT_ERROR: {
unsigned short error = getrpacketblock(&state->rpacket);
const char *str = (const char *)state->rpacket.data + 4;
size_t strn = state->rbytes - 4;
state->error = (tftp_error_t)error;
if(tftp_strnlen(str, strn) < strn)
infof(data, "TFTP error: %s", str);
break;
}
case TFTP_EVENT_ACK:
break;
case TFTP_EVENT_OACK:
result = tftp_parse_option_ack(state,
(const char *)state->rpacket.data + 2,
state->rbytes-2);
if(result)
return result;
break;
case TFTP_EVENT_RRQ:
case TFTP_EVENT_WRQ:
default:
failf(data, "%s", "Internal error: Unexpected packet");
break;
}
/* Update the progress meter */
result = Curl_pgrsUpdate(data);
if(result) {
tftp_state_machine(state, TFTP_EVENT_ERROR);
return result;
}
}
return result;
}
/**********************************************************
*
* tftp_state_timeout
*
* Check if timeouts have been reached
*
**********************************************************/
static timediff_t tftp_state_timeout(struct tftp_conn *state,
tftp_event_t *event)
{
time_t current;
timediff_t timeout_ms;
if(event)
*event = TFTP_EVENT_NONE;
timeout_ms = Curl_timeleft_ms(state->data);
if(timeout_ms < 0) {
state->error = TFTP_ERR_TIMEOUT;
state->state = TFTP_STATE_FIN;
return timeout_ms;
}
current = time(NULL);
if(current > state->rx_time + state->retry_time) {
if(event)
*event = TFTP_EVENT_TIMEOUT;
state->rx_time = time(NULL); /* update even though we received nothing */
}
return timeout_ms;
}
/**********************************************************
*
* tftp_multi_statemach
*
* Handle single RX socket event and return
*
**********************************************************/
static CURLcode tftp_multi_statemach(struct Curl_easy *data, bool *done)
{
tftp_event_t event;
CURLcode result = CURLE_OK;
struct connectdata *conn = data->conn;
struct tftp_conn *state = Curl_conn_meta_get(conn, CURL_META_TFTP_CONN);
timediff_t timeout_ms;
*done = FALSE;
if(!state)
return CURLE_FAILED_INIT;
timeout_ms = tftp_state_timeout(state, &event);
if(timeout_ms < 0) {
failf(data, "TFTP response timeout");
return CURLE_OPERATION_TIMEDOUT;
}
if(event != TFTP_EVENT_NONE) {
result = tftp_state_machine(state, event);
if(result)
return result;
*done = (state->state == TFTP_STATE_FIN);
if(*done)
/* Tell curl we are done */
Curl_xfer_setup_nop(data);
}
else {
/* no timeouts to handle, check our socket */
int rc = SOCKET_READABLE(state->sockfd, 0);
if(rc == -1) {
/* bail out */
int error = SOCKERRNO;
char buffer[STRERROR_LEN];
failf(data, "%s", curlx_strerror(error, buffer, sizeof(buffer)));
state->event = TFTP_EVENT_ERROR;
}
else if(rc) {
result = tftp_receive_packet(data, state);
if(result)
return result;
result = tftp_state_machine(state, state->event);
if(result)
return result;
*done = (state->state == TFTP_STATE_FIN);
if(*done)
/* Tell curl we are done */
Curl_xfer_setup_nop(data);
}
/* if rc == 0, then select() timed out */
}
return result;
}
/**********************************************************
*
* tftp_doing
*
* Called from multi.c while DOing
*
**********************************************************/
static CURLcode tftp_doing(struct Curl_easy *data, bool *dophase_done)
{
CURLcode result;
result = tftp_multi_statemach(data, dophase_done);
if(*dophase_done) {
DEBUGF(infof(data, "DO phase is complete"));
}
else if(!result) {
/* The multi code does not have this logic for the DOING state so we
provide it for TFTP since it may do the entire transfer in this
state. */
result = Curl_pgrsCheck(data);
}
return result;
}
/**********************************************************
*
* tftp_perform
*
* Entry point for transfer from tftp_do, starts state mach
*
**********************************************************/
static CURLcode tftp_perform(struct Curl_easy *data, bool *dophase_done)
{
CURLcode result = CURLE_OK;
struct connectdata *conn = data->conn;
struct tftp_conn *state = Curl_conn_meta_get(conn, CURL_META_TFTP_CONN);
*dophase_done = FALSE;
if(!state)
return CURLE_FAILED_INIT;
result = tftp_state_machine(state, TFTP_EVENT_INIT);
if((state->state == TFTP_STATE_FIN) || result)
return result;
result = tftp_multi_statemach(data, dophase_done);
if(*dophase_done)
DEBUGF(infof(data, "DO phase is complete"));
return result;
}
/**********************************************************
*
* tftp_do
*
* The do callback
*
* This callback initiates the TFTP transfer
*
**********************************************************/
static CURLcode tftp_do(struct Curl_easy *data, bool *done)
{
struct connectdata *conn = data->conn;
struct tftp_conn *state = Curl_conn_meta_get(conn, CURL_META_TFTP_CONN);
CURLcode result;
*done = FALSE;
if(!state) {
result = tftp_connect(data, done);
if(result)
return result;
state = Curl_conn_meta_get(conn, CURL_META_TFTP_CONN);
if(!state)
return CURLE_TFTP_ILLEGAL;
}
result = tftp_perform(data, done);
/* If tftp_perform() returned an error, use that for return code. If it
was OK, see if tftp_translate_code() has an error. */
if(!result)
/* If we have encountered an internal tftp error, translate it. */
result = tftp_translate_code(state->error);
return result;
}
static CURLcode tftp_setup_connection(struct Curl_easy *data,
struct connectdata *conn)
{
char *path = data->state.up.path;
size_t len = strlen(path);
conn->transport_wanted = TRNSPRT_UDP;
/* TFTP URLs support a trailing ";mode=netascii" or ";mode=octet" */
if((len >= 14) && !memcmp(&path[len - 14], ";mode=netascii", 14)) {
data->state.prefer_ascii = TRUE;
path[len - 14] = 0; /* cut it there */
}
else if((len >= 11) && !memcmp(&path[len - 11], ";mode=octet", 11)) {
data->state.prefer_ascii = FALSE;
path[len - 11] = 0; /* cut it there */
}
return CURLE_OK;
}
/*
* TFTP protocol handler.
*/
const struct Curl_protocol Curl_protocol_tftp = {
tftp_setup_connection, /* setup_connection */
tftp_do, /* do_it */
tftp_done, /* done */
ZERO_NULL, /* do_more */
tftp_connect, /* connect_it */
tftp_multi_statemach, /* connecting */
tftp_doing, /* doing */
tftp_pollset, /* proto_pollset */
tftp_pollset, /* doing_pollset */
ZERO_NULL, /* domore_pollset */
ZERO_NULL, /* perform_pollset */
ZERO_NULL, /* disconnect */
ZERO_NULL, /* write_resp */
ZERO_NULL, /* write_resp_hd */
ZERO_NULL, /* connection_is_dead */
ZERO_NULL, /* attach connection */
ZERO_NULL, /* follow */
};
#endif