view progressmeter.c @ 1715:3974f087d9c0

Disallow leading lines before the ident for server (#102) Per RFC4253 4.2 clients must be able to process other lines of data before the version string, server behavior is not defined neither with MUST/SHOULD nor with MAY. If server process up to 50 lines too - it may cause too long hanging session with invalid/evil client that consume host resources and potentially may lead to DDoS on poor embedded boxes. Let's require first line from client to be version string and fail early if it's not - matches both RFC and real OpenSSH behavior.
author Vladislav Grishenko <themiron@users.noreply.github.com>
date Mon, 15 Jun 2020 18:22:18 +0500
parents b72f98803e46
children
line wrap: on
line source

#ifdef PROGRESS_METER
/*
 * Copyright (c) 2003 Nils Nordman.  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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 "includes.h"
/*RCSID("$OpenBSD: progressmeter.c,v 1.24 2005/06/07 13:25:23 jaredy Exp $");*/

#include "progressmeter.h"
#include "atomicio.h"
#include "scpmisc.h"

#define DEFAULT_WINSIZE 80
#define MAX_WINSIZE 512
#define PADDING 1		/* padding between the progress indicators */
#define UPDATE_INTERVAL 1	/* update the progress meter every second */
#define STALL_TIME 5		/* we're stalled after this many seconds */

/* determines whether we can output to the terminal */
static int can_output(void);

/* formats and inserts the specified size into the given buffer */
static void format_size(char *, int, off_t);
static void format_rate(char *, int, off_t);

/* window resizing */
static void sig_winch(int);
static void setscreensize(void);

/* updates the progressmeter to reflect the current state of the transfer */
void refresh_progress_meter(void);

/* signal handler for updating the progress meter */
static void update_progress_meter(int);

static time_t start;		/* start progress */
static time_t last_update;	/* last progress update */
static char *file;		/* name of the file being transferred */
static off_t end_pos;		/* ending position of transfer */
static off_t cur_pos;		/* transfer position as of last refresh */
static volatile off_t *counter;	/* progress counter */
static long stalled;		/* how long we have been stalled */
static int bytes_per_second;	/* current speed in bytes per second */
static int win_size;		/* terminal window size */
static volatile sig_atomic_t win_resized; /* for window resizing */

/* units for format_size */
static const char unit[] = " KMGT";

static int
can_output(void)
{
	return (getpgrp() == tcgetpgrp(STDOUT_FILENO));
}

static void
format_rate(char *buf, int size, off_t bytes)
{
	int i;

	bytes *= 100;
	for (i = 0; bytes >= 100*1000 && unit[i] != 'T'; i++)
		bytes = (bytes + 512) / 1024;
	if (i == 0) {
		i++;
		bytes = (bytes + 512) / 1024;
	}
	snprintf(buf, size, "%3lld.%1lld%c%s",
	    (long long) (bytes + 5) / 100,
	    (long long) (bytes + 5) / 10 % 10,
	    unit[i],
	    i ? "B" : " ");
}

static void
format_size(char *buf, int size, off_t bytes)
{
	int i;

	for (i = 0; bytes >= 10000 && unit[i] != 'T'; i++)
		bytes = (bytes + 512) / 1024;
	snprintf(buf, size, "%4lld%c%s",
	    (long long) bytes,
	    unit[i],
	    i ? "B" : " ");
}

void
refresh_progress_meter(void)
{
	char buf[MAX_WINSIZE + 1];
	time_t now;
	off_t transferred;
	double elapsed;
	int percent;
	off_t bytes_left;
	int cur_speed;
	int hours, minutes, seconds;
	int i, len;
	int file_len;

	transferred = *counter - cur_pos;
	cur_pos = *counter;
	now = time(NULL);
	bytes_left = end_pos - cur_pos;

	if (bytes_left > 0)
		elapsed = now - last_update;
	else {
		elapsed = now - start;
		/* Calculate true total speed when done */
		transferred = end_pos;
		bytes_per_second = 0;
	}

	/* calculate speed */
	if (elapsed != 0)
		cur_speed = (transferred / elapsed);
	else
		cur_speed = transferred;

#define AGE_FACTOR 0.9
	if (bytes_per_second != 0) {
		bytes_per_second = (bytes_per_second * AGE_FACTOR) +
		    (cur_speed * (1.0 - AGE_FACTOR));
	} else
		bytes_per_second = cur_speed;

	/* filename */
	buf[0] = '\0';
	file_len = win_size - 35;
	if (file_len > 0) {
		len = snprintf(buf, file_len + 1, "\r%s", file);
		if (len < 0)
			len = 0;
		if (len >= file_len + 1)
			len = file_len;
		for (i = len;  i < file_len; i++ )
			buf[i] = ' ';
		buf[file_len] = '\0';
	}

	/* percent of transfer done */
	if (end_pos != 0)
		percent = ((float)cur_pos / end_pos) * 100;
	else
		percent = 100;
	snprintf(buf + strlen(buf), win_size - strlen(buf),
	    " %3d%% ", percent);

	/* amount transferred */
	format_size(buf + strlen(buf), win_size - strlen(buf),
	    cur_pos);
	strlcat(buf, " ", win_size);

	/* bandwidth usage */
	format_rate(buf + strlen(buf), win_size - strlen(buf),
	    (off_t)bytes_per_second);
	strlcat(buf, "/s ", win_size);

	/* ETA */
	if (!transferred)
		stalled += elapsed;
	else
		stalled = 0;

	if (stalled >= STALL_TIME)
		strlcat(buf, "- stalled -", win_size);
	else if (bytes_per_second == 0 && bytes_left)
		strlcat(buf, "  --:-- ETA", win_size);
	else {
		if (bytes_left > 0)
			seconds = bytes_left / bytes_per_second;
		else
			seconds = elapsed;

		hours = seconds / 3600;
		seconds -= hours * 3600;
		minutes = seconds / 60;
		seconds -= minutes * 60;

		if (hours != 0)
			snprintf(buf + strlen(buf), win_size - strlen(buf),
			    "%d:%02d:%02d", hours, minutes, seconds);
		else
			snprintf(buf + strlen(buf), win_size - strlen(buf),
			    "  %02d:%02d", minutes, seconds);

		if (bytes_left > 0)
			strlcat(buf, " ETA", win_size);
		else
			strlcat(buf, "    ", win_size);
	}

	atomicio(vwrite, STDOUT_FILENO, buf, win_size - 1);
	last_update = now;
}

static void
update_progress_meter(int ignore)
{
	int save_errno;

	save_errno = errno;

	if (win_resized) {
		setscreensize();
		win_resized = 0;
	}
	if (can_output())
		refresh_progress_meter();

	signal(SIGALRM, update_progress_meter);
	alarm(UPDATE_INTERVAL);
	errno = save_errno;
}

void
start_progress_meter(char *f, off_t filesize, off_t *ctr)
{
	start = last_update = time(NULL);
	file = f;
	end_pos = filesize;
	cur_pos = 0;
	counter = ctr;
	stalled = 0;
	bytes_per_second = 0;

	setscreensize();
	if (can_output())
		refresh_progress_meter();

	signal(SIGALRM, update_progress_meter);
	signal(SIGWINCH, sig_winch);
	alarm(UPDATE_INTERVAL);
}

void
stop_progress_meter(void)
{
	alarm(0);

	if (!can_output())
		return;

	/* Ensure we complete the progress */
	if (cur_pos != end_pos)
		refresh_progress_meter();

	atomicio(vwrite, STDOUT_FILENO, "\n", 1);
}

static void
sig_winch(int sig)
{
	win_resized = 1;
}

static void
setscreensize(void)
{
	struct winsize winsize;

	if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &winsize) != -1 &&
	    winsize.ws_col != 0) {
		if (winsize.ws_col > MAX_WINSIZE)
			win_size = MAX_WINSIZE;
		else
			win_size = winsize.ws_col;
	} else
		win_size = DEFAULT_WINSIZE;
	win_size += 1;					/* trailing \0 */
}
#endif /* PROGRESS_METER */