289 lines
8.3 KiB
C
289 lines
8.3 KiB
C
/* $NetBSD: tftpsubs.c,v 1.10 2006/04/09 18:45:19 christos Exp $ */
|
|
|
|
/*
|
|
* Copyright (c) 1983, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
#ifndef lint
|
|
#if 0
|
|
static char sccsid[] = "@(#)tftpsubs.c 8.1 (Berkeley) 6/6/93";
|
|
#else
|
|
__RCSID("$NetBSD: tftpsubs.c,v 1.10 2006/04/09 18:45:19 christos Exp $");
|
|
#endif
|
|
#endif /* not lint */
|
|
|
|
/* Simple minded read-ahead/write-behind subroutines for tftp user and
|
|
server. Written originally with multiple buffers in mind, but current
|
|
implementation has two buffer logic wired in.
|
|
|
|
Todo: add some sort of final error check so when the write-buffer
|
|
is finally flushed, the caller can detect if the disk filled up
|
|
(or had an i/o error) and return a nak to the other side.
|
|
|
|
Jim Guyton 10/85
|
|
*/
|
|
|
|
#include <sys/types.h>
|
|
#include <sys/socket.h>
|
|
#include <sys/ioctl.h>
|
|
#include <netinet/in.h>
|
|
#include <arpa/tftp.h>
|
|
|
|
#include <stdio.h>
|
|
#include <unistd.h>
|
|
|
|
#include "tftpsubs.h"
|
|
|
|
struct bf {
|
|
int counter; /* size of data in buffer, or flag */
|
|
char buf[MAXPKTSIZE]; /* room for data packet */
|
|
} bfs[2];
|
|
|
|
/* Values for bf.counter */
|
|
#define BF_ALLOC -3 /* alloc'd but not yet filled */
|
|
#define BF_FREE -2 /* free */
|
|
/* [-1 .. SEGSIZE] = size of data in the data buffer */
|
|
|
|
static int nextone; /* index of next buffer to use */
|
|
static int current; /* index of buffer in use */
|
|
|
|
/* control flags for crlf conversions */
|
|
int newline = 0; /* fillbuf: in middle of newline expansion */
|
|
int prevchar = -1; /* putbuf: previous char (cr check) */
|
|
|
|
static struct tftphdr *rw_init __P((int));
|
|
|
|
struct tftphdr *
|
|
w_init() /* write-behind */
|
|
{
|
|
return rw_init(0);
|
|
}
|
|
|
|
struct tftphdr *
|
|
r_init() /* read-ahead */
|
|
{
|
|
return rw_init(1);
|
|
}
|
|
|
|
static struct tftphdr *
|
|
rw_init(x) /* init for either read-ahead or write-behind */
|
|
int x; /* zero for write-behind, one for read-head */
|
|
{
|
|
newline = 0; /* init crlf flag */
|
|
prevchar = -1;
|
|
bfs[0].counter = BF_ALLOC; /* pass out the first buffer */
|
|
current = 0;
|
|
bfs[1].counter = BF_FREE;
|
|
nextone = x; /* ahead or behind? */
|
|
return (struct tftphdr *)(void *)bfs[0].buf;
|
|
}
|
|
|
|
/* Have emptied current buffer by sending to net and getting ack.
|
|
Free it and return next buffer filled with data.
|
|
*/
|
|
int
|
|
readit(file, dpp, amt, convert)
|
|
FILE *file; /* file opened for read */
|
|
struct tftphdr **dpp;
|
|
size_t amt;
|
|
int convert; /* if true, convert to ascii */
|
|
{
|
|
struct bf *b;
|
|
|
|
bfs[current].counter = BF_FREE; /* free old one */
|
|
current = !current; /* "incr" current */
|
|
|
|
b = &bfs[current]; /* look at new buffer */
|
|
if (b->counter == BF_FREE) /* if it's empty */
|
|
read_ahead(file, amt, convert); /* fill it */
|
|
/* assert(b->counter != BF_FREE);*//* check */
|
|
*dpp = (struct tftphdr *)(void *)b->buf; /* set caller's ptr */
|
|
return b->counter;
|
|
}
|
|
|
|
/*
|
|
* fill the input buffer, doing ascii conversions if requested
|
|
* conversions are lf -> cr,lf and cr -> cr, nul
|
|
*/
|
|
void
|
|
read_ahead(file, amt, convert)
|
|
FILE *file; /* file opened for read */
|
|
size_t amt; /* number of bytes to read */
|
|
int convert; /* if true, convert to ascii */
|
|
{
|
|
int i;
|
|
char *p;
|
|
int c;
|
|
struct bf *b;
|
|
struct tftphdr *dp;
|
|
|
|
b = &bfs[nextone]; /* look at "next" buffer */
|
|
if (b->counter != BF_FREE) /* nop if not free */
|
|
return;
|
|
nextone = !nextone; /* "incr" next buffer ptr */
|
|
|
|
dp = (struct tftphdr *)(void *)b->buf;
|
|
|
|
if (convert == 0) {
|
|
b->counter = read(fileno(file), dp->th_data, amt);
|
|
return;
|
|
}
|
|
|
|
p = dp->th_data;
|
|
for (i = 0 ; i < amt; i++) {
|
|
if (newline) {
|
|
if (prevchar == '\n')
|
|
c = '\n'; /* lf to cr,lf */
|
|
else c = '\0'; /* cr to cr,nul */
|
|
newline = 0;
|
|
}
|
|
else {
|
|
c = getc(file);
|
|
if (c == EOF) break;
|
|
if (c == '\n' || c == '\r') {
|
|
prevchar = c;
|
|
c = '\r';
|
|
newline = 1;
|
|
}
|
|
}
|
|
*p++ = c;
|
|
}
|
|
b->counter = (int)(p - dp->th_data);
|
|
}
|
|
|
|
/* Update count associated with the buffer, get new buffer
|
|
from the queue. Calls write_behind only if next buffer not
|
|
available.
|
|
*/
|
|
int
|
|
writeit(file, dpp, ct, convert)
|
|
FILE *file;
|
|
struct tftphdr **dpp;
|
|
int ct, convert;
|
|
{
|
|
bfs[current].counter = ct; /* set size of data to write */
|
|
current = !current; /* switch to other buffer */
|
|
if (bfs[current].counter != BF_FREE) /* if not free */
|
|
if (write_behind(file, convert) == -1) /* flush it */
|
|
return -1;
|
|
bfs[current].counter = BF_ALLOC; /* mark as alloc'd */
|
|
*dpp = (struct tftphdr *)(void *)bfs[current].buf;
|
|
return ct; /* this is a lie of course */
|
|
}
|
|
|
|
/*
|
|
* Output a buffer to a file, converting from netascii if requested.
|
|
* CR,NUL -> CR and CR,LF => LF.
|
|
* Note spec is undefined if we get CR as last byte of file or a
|
|
* CR followed by anything else. In this case we leave it alone.
|
|
*/
|
|
int
|
|
write_behind(file, convert)
|
|
FILE *file;
|
|
int convert;
|
|
{
|
|
char *buf;
|
|
int count;
|
|
int ct;
|
|
char *p;
|
|
int c; /* current character */
|
|
struct bf *b;
|
|
struct tftphdr *dp;
|
|
|
|
b = &bfs[nextone];
|
|
if (b->counter < -1) /* anything to flush? */
|
|
return 0; /* just nop if nothing to do */
|
|
|
|
count = b->counter; /* remember byte count */
|
|
b->counter = BF_FREE; /* reset flag */
|
|
dp = (struct tftphdr *)(void *)b->buf;
|
|
nextone = !nextone; /* incr for next time */
|
|
buf = dp->th_data;
|
|
|
|
if (count <= 0) return -1; /* nak logic? */
|
|
|
|
if (convert == 0)
|
|
return write(fileno(file), buf, (size_t)count);
|
|
|
|
p = buf;
|
|
ct = count;
|
|
while (ct--) { /* loop over the buffer */
|
|
c = *p++; /* pick up a character */
|
|
if (prevchar == '\r') { /* if prev char was cr */
|
|
if (c == '\n') /* if have cr,lf then just */
|
|
(void)fseeko(file, (off_t)-1, 1); /* smash lf on top of the cr */
|
|
else
|
|
if (c == '\0') /* if have cr,nul then */
|
|
goto skipit; /* just skip over the putc */
|
|
/* else just fall through and allow it */
|
|
}
|
|
if (putc(c, file) == EOF)
|
|
return -1;
|
|
skipit:
|
|
prevchar = c;
|
|
}
|
|
return count;
|
|
}
|
|
|
|
|
|
/* When an error has occurred, it is possible that the two sides
|
|
* are out of synch. Ie: that what I think is the other side's
|
|
* response to packet N is really their response to packet N-1.
|
|
*
|
|
* So, to try to prevent that, we flush all the input queued up
|
|
* for us on the network connection on our host.
|
|
*
|
|
* We return the number of packets we flushed (mostly for reporting
|
|
* when trace is active).
|
|
*/
|
|
|
|
int
|
|
/*ARGSUSED*/
|
|
synchnet(f, bsize)
|
|
int f; /* socket to flush */
|
|
size_t bsize; /* size of buffer to sync */
|
|
{
|
|
int i, j = 0;
|
|
char rbuf[PKTSIZE];
|
|
struct sockaddr_storage from;
|
|
socklen_t fromlen;
|
|
|
|
for (;;) {
|
|
(void) ioctl(f, FIONREAD, &i);
|
|
if (i) {
|
|
j++;
|
|
fromlen = sizeof from;
|
|
(void) recvfrom(f, rbuf, sizeof (rbuf), 0,
|
|
(struct sockaddr *)(void *)&from, &fromlen);
|
|
} else {
|
|
return(j);
|
|
}
|
|
}
|
|
}
|