Fix culpable lack of generality in keyboard-interactive

[sgt/putty] / scp.c

/*
 * scp.c  -  Scp (Secure Copy) client for PuTTY.
 * Joris van Rantwijk, Simon Tatham
 *
 * This is mainly based on ssh-1.2.26/scp.c by Timo Rinne & Tatu Ylonen.
 * They, in turn, used stuff from BSD rcp.
 * 
 * (SGT, 2001-09-10: Joris van Rantwijk assures me that although
 * this file as originally submitted was inspired by, and
 * _structurally_ based on, ssh-1.2.26's scp.c, there wasn't any
 * actual code duplicated, so the above comment shouldn't give rise
 * to licensing issues.)
 */

#include <windows.h>
#ifndef AUTO_WINSOCK
#ifdef WINSOCK_TWO
#include <winsock2.h>
#else
#include <winsock.h>
#endif
#endif
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <limits.h>
#include <time.h>
#include <assert.h>

#define PUTTY_DO_GLOBALS
#include "putty.h"
#include "ssh.h"
#include "sftp.h"
#include "winstuff.h"
#include "storage.h"

#define TIME_POSIX_TO_WIN(t, ft) (*(LONGLONG*)&(ft) = \
	((LONGLONG) (t) + (LONGLONG) 11644473600) * (LONGLONG) 10000000)
#define TIME_WIN_TO_POSIX(ft, t) ((t) = (unsigned long) \
	((*(LONGLONG*)&(ft)) / (LONGLONG) 10000000 - (LONGLONG) 11644473600))

/* GUI Adaptation - Sept 2000 */

/* This is just a base value from which the main message numbers are
 * derived. */
#define   WM_APP_BASE		0x8000

/* These two pass a single character value in wParam. They represent
 * the visible output from PSCP. */
#define   WM_STD_OUT_CHAR	( WM_APP_BASE+400 )
#define   WM_STD_ERR_CHAR	( WM_APP_BASE+401 )

/* These pass a transfer status update. WM_STATS_CHAR passes a single
 * character in wParam, and is called repeatedly to pass the name of
 * the file, terminated with "\n". WM_STATS_SIZE passes the size of
 * the file being transferred in wParam. WM_STATS_ELAPSED is called
 * to pass the elapsed time (in seconds) in wParam, and
 * WM_STATS_PERCENT passes the percentage of the transfer which is
 * complete, also in wParam. */
#define   WM_STATS_CHAR		( WM_APP_BASE+402 )
#define   WM_STATS_SIZE 	( WM_APP_BASE+403 )
#define   WM_STATS_PERCENT	( WM_APP_BASE+404 )
#define   WM_STATS_ELAPSED	( WM_APP_BASE+405 )

/* These are used at the end of a run to pass an error code in
 * wParam: zero means success, nonzero means failure. WM_RET_ERR_CNT
 * is used after a copy, and WM_LS_RET_ERR_CNT is used after a file
 * list operation. */
#define   WM_RET_ERR_CNT	( WM_APP_BASE+406 )
#define   WM_LS_RET_ERR_CNT	( WM_APP_BASE+407 )

/* More transfer status update messages. WM_STATS_DONE passes the
 * number of bytes sent so far in wParam. WM_STATS_ETA passes the
 * estimated time to completion (in seconds). WM_STATS_RATEBS passes
 * the average transfer rate (in bytes per second). */
#define   WM_STATS_DONE		( WM_APP_BASE+408 )
#define   WM_STATS_ETA		( WM_APP_BASE+409 )
#define   WM_STATS_RATEBS	( WM_APP_BASE+410 )

static int list = 0;
static int verbose = 0;
static int recursive = 0;
static int preserve = 0;
static int targetshouldbedirectory = 0;
static int statistics = 1;
static int portnumber = 0;
static int prev_stats_len = 0;
static int scp_unsafe_mode = 0;
static char *password = NULL;
static int errs = 0;
/* GUI Adaptation - Sept 2000 */
#define NAME_STR_MAX 2048
static char statname[NAME_STR_MAX + 1];
static unsigned long statsize = 0;
static unsigned long statdone = 0;
static unsigned long stateta = 0;
static unsigned long statratebs = 0;
static int statperct = 0;
static unsigned long statelapsed = 0;
static int gui_mode = 0;
static char *gui_hwnd = NULL;
static int using_sftp = 0;

static void source(char *src);
static void rsource(char *src);
static void sink(char *targ, char *src);
/* GUI Adaptation - Sept 2000 */
static void tell_char(FILE * stream, char c);
static void tell_str(FILE * stream, char *str);
static void tell_user(FILE * stream, char *fmt, ...);
static void gui_update_stats(char *name, unsigned long size,
			     int percentage, unsigned long elapsed, 
			     unsigned long done, unsigned long eta,
			     unsigned long ratebs);

/*
 * The maximum amount of queued data we accept before we stop and
 * wait for the server to process some.
 */
#define MAX_SCP_BUFSIZE 16384

void ldisc_send(char *buf, int len, int interactive)
{
    /*
     * This is only here because of the calls to ldisc_send(NULL,
     * 0) in ssh.c. Nothing in PSCP actually needs to use the ldisc
     * as an ldisc. So if we get called with any real data, I want
     * to know about it.
     */
    assert(len == 0);
}

/* GUI Adaptation - Sept 2000 */
static void send_msg(HWND h, UINT message, WPARAM wParam)
{
    while (!PostMessage(h, message, wParam, 0))
	SleepEx(1000, TRUE);
}

static void tell_char(FILE * stream, char c)
{
    if (!gui_mode)
	fputc(c, stream);
    else {
	unsigned int msg_id = WM_STD_OUT_CHAR;
	if (stream == stderr)
	    msg_id = WM_STD_ERR_CHAR;
	send_msg((HWND) atoi(gui_hwnd), msg_id, (WPARAM) c);
    }
}

static void tell_str(FILE * stream, char *str)
{
    unsigned int i;

    for (i = 0; i < strlen(str); ++i)
	tell_char(stream, str[i]);
}

static void tell_user(FILE * stream, char *fmt, ...)
{
    char str[0x100];		       /* Make the size big enough */
    va_list ap;
    va_start(ap, fmt);
    vsprintf(str, fmt, ap);
    va_end(ap);
    strcat(str, "\n");
    tell_str(stream, str);
}

static void gui_update_stats(char *name, unsigned long size,
			     int percentage, unsigned long elapsed,
			     unsigned long done, unsigned long eta,
			     unsigned long ratebs)
{
    unsigned int i;

    if (strcmp(name, statname) != 0) {
	for (i = 0; i < strlen(name); ++i)
	    send_msg((HWND) atoi(gui_hwnd), WM_STATS_CHAR,
		     (WPARAM) name[i]);
	send_msg((HWND) atoi(gui_hwnd), WM_STATS_CHAR, (WPARAM) '\n');
	strcpy(statname, name);
    }
    if (statsize != size) {
	send_msg((HWND) atoi(gui_hwnd), WM_STATS_SIZE, (WPARAM) size);
	statsize = size;
    }
    if (statdone != done) {
	send_msg((HWND) atoi(gui_hwnd), WM_STATS_DONE, (WPARAM) done);
	statdone = done;
    }
    if (stateta != eta) {
	send_msg((HWND) atoi(gui_hwnd), WM_STATS_ETA, (WPARAM) eta);
	stateta = eta;
    }
    if (statratebs != ratebs) {
	send_msg((HWND) atoi(gui_hwnd), WM_STATS_RATEBS, (WPARAM) ratebs);
	statratebs = ratebs;
    }
    if (statelapsed != elapsed) {
	send_msg((HWND) atoi(gui_hwnd), WM_STATS_ELAPSED,
		 (WPARAM) elapsed);
	statelapsed = elapsed;
    }
    if (statperct != percentage) {
	send_msg((HWND) atoi(gui_hwnd), WM_STATS_PERCENT,
		 (WPARAM) percentage);
	statperct = percentage;
    }
}

/*
 *  Print an error message and perform a fatal exit.
 */
void fatalbox(char *fmt, ...)
{
    char str[0x100];		       /* Make the size big enough */
    va_list ap;
    va_start(ap, fmt);
    strcpy(str, "Fatal: ");
    vsprintf(str + strlen(str), fmt, ap);
    va_end(ap);
    strcat(str, "\n");
    tell_str(stderr, str);
    errs++;

    if (gui_mode) {
	unsigned int msg_id = WM_RET_ERR_CNT;
	if (list)
	    msg_id = WM_LS_RET_ERR_CNT;
	while (!PostMessage
	       ((HWND) atoi(gui_hwnd), msg_id, (WPARAM) errs,
		0 /*lParam */ ))SleepEx(1000, TRUE);
    }

    cleanup_exit(1);
}
void connection_fatal(char *fmt, ...)
{
    char str[0x100];		       /* Make the size big enough */
    va_list ap;
    va_start(ap, fmt);
    strcpy(str, "Fatal: ");
    vsprintf(str + strlen(str), fmt, ap);
    va_end(ap);
    strcat(str, "\n");
    tell_str(stderr, str);
    errs++;

    if (gui_mode) {
	unsigned int msg_id = WM_RET_ERR_CNT;
	if (list)
	    msg_id = WM_LS_RET_ERR_CNT;
	while (!PostMessage
	       ((HWND) atoi(gui_hwnd), msg_id, (WPARAM) errs,
		0 /*lParam */ ))SleepEx(1000, TRUE);
    }

    cleanup_exit(1);
}

/*
 * Be told what socket we're supposed to be using.
 */
static SOCKET scp_ssh_socket;
char *do_select(SOCKET skt, int startup)
{
    if (startup)
	scp_ssh_socket = skt;
    else
	scp_ssh_socket = INVALID_SOCKET;
    return NULL;
}
extern int select_result(WPARAM, LPARAM);

/*
 * Receive a block of data from the SSH link. Block until all data
 * is available.
 *
 * To do this, we repeatedly call the SSH protocol module, with our
 * own trap in from_backend() to catch the data that comes back. We
 * do this until we have enough data.
 */

static unsigned char *outptr;	       /* where to put the data */
static unsigned outlen;		       /* how much data required */
static unsigned char *pending = NULL;  /* any spare data */
static unsigned pendlen = 0, pendsize = 0;	/* length and phys. size of buffer */
int from_backend(int is_stderr, char *data, int datalen)
{
    unsigned char *p = (unsigned char *) data;
    unsigned len = (unsigned) datalen;

    assert(len > 0);

    /*
     * stderr data is just spouted to local stderr and otherwise
     * ignored.
     */
    if (is_stderr) {
	fwrite(data, 1, len, stderr);
	return 0;
    }

    /*
     * If this is before the real session begins, just return.
     */
    if (!outptr)
	return 0;

    if (outlen > 0) {
	unsigned used = outlen;
	if (used > len)
	    used = len;
	memcpy(outptr, p, used);
	outptr += used;
	outlen -= used;
	p += used;
	len -= used;
    }

    if (len > 0) {
	if (pendsize < pendlen + len) {
	    pendsize = pendlen + len + 4096;
	    pending = (pending ? srealloc(pending, pendsize) :
		       smalloc(pendsize));
	    if (!pending)
		fatalbox("Out of memory");
	}
	memcpy(pending + pendlen, p, len);
	pendlen += len;
    }

    return 0;
}
static int scp_process_network_event(void)
{
    fd_set readfds;

    FD_ZERO(&readfds);
    FD_SET(scp_ssh_socket, &readfds);
    if (select(1, &readfds, NULL, NULL, NULL) < 0)
	return 0;		       /* doom */
    select_result((WPARAM) scp_ssh_socket, (LPARAM) FD_READ);
    return 1;
}
static int ssh_scp_recv(unsigned char *buf, int len)
{
    outptr = buf;
    outlen = len;

    /*
     * See if the pending-input block contains some of what we
     * need.
     */
    if (pendlen > 0) {
	unsigned pendused = pendlen;
	if (pendused > outlen)
	    pendused = outlen;
	memcpy(outptr, pending, pendused);
	memmove(pending, pending + pendused, pendlen - pendused);
	outptr += pendused;
	outlen -= pendused;
	pendlen -= pendused;
	if (pendlen == 0) {
	    pendsize = 0;
	    sfree(pending);
	    pending = NULL;
	}
	if (outlen == 0)
	    return len;
    }

    while (outlen > 0) {
	if (!scp_process_network_event())
	    return 0;		       /* doom */
    }

    return len;
}

/*
 * Loop through the ssh connection and authentication process.
 */
static void ssh_scp_init(void)
{
    if (scp_ssh_socket == INVALID_SOCKET)
	return;
    while (!back->sendok()) {
	fd_set readfds;
	FD_ZERO(&readfds);
	FD_SET(scp_ssh_socket, &readfds);
	if (select(1, &readfds, NULL, NULL, NULL) < 0)
	    return;		       /* doom */
	select_result((WPARAM) scp_ssh_socket, (LPARAM) FD_READ);
    }
    using_sftp = !ssh_fallback_cmd;
}

/*
 *  Print an error message and exit after closing the SSH link.
 */
static void bump(char *fmt, ...)
{
    char str[0x100];		       /* Make the size big enough */
    va_list ap;
    va_start(ap, fmt);
    strcpy(str, "Fatal: ");
    vsprintf(str + strlen(str), fmt, ap);
    va_end(ap);
    strcat(str, "\n");
    tell_str(stderr, str);
    errs++;

    if (back != NULL && back->socket() != NULL) {
	char ch;
	back->special(TS_EOF);
	ssh_scp_recv(&ch, 1);
    }

    if (gui_mode) {
	unsigned int msg_id = WM_RET_ERR_CNT;
	if (list)
	    msg_id = WM_LS_RET_ERR_CNT;
	while (!PostMessage
	       ((HWND) atoi(gui_hwnd), msg_id, (WPARAM) errs,
		0 /*lParam */ ))SleepEx(1000, TRUE);
    }

    cleanup_exit(1);
}

/*
 *  Open an SSH connection to user@host and execute cmd.
 */
static void do_cmd(char *host, char *user, char *cmd)
{
    char *err, *realhost;
    DWORD namelen;

    if (host == NULL || host[0] == '\0')
	bump("Empty host name");

    /* Try to load settings for this host */
    do_defaults(host, &cfg);
    if (cfg.host[0] == '\0') {
	/* No settings for this host; use defaults */
	do_defaults(NULL, &cfg);
	strncpy(cfg.host, host, sizeof(cfg.host) - 1);
	cfg.host[sizeof(cfg.host) - 1] = '\0';
	cfg.port = 22;
    }

    /*
     * Trim leading whitespace off the hostname if it's there.
     */
    {
	int space = strspn(cfg.host, " \t");
	memmove(cfg.host, cfg.host+space, 1+strlen(cfg.host)-space);
    }

    /* See if host is of the form user@host */
    if (cfg.host[0] != '\0') {
	char *atsign = strchr(cfg.host, '@');
	/* Make sure we're not overflowing the user field */
	if (atsign) {
	    if (atsign - cfg.host < sizeof cfg.username) {
		strncpy(cfg.username, cfg.host, atsign - cfg.host);
		cfg.username[atsign - cfg.host] = '\0';
	    }
	    memmove(cfg.host, atsign + 1, 1 + strlen(atsign + 1));
	}
    }

    /*
     * Trim a colon suffix off the hostname if it's there.
     */
    cfg.host[strcspn(cfg.host, ":")] = '\0';

    /* Set username */
    if (user != NULL && user[0] != '\0') {
	strncpy(cfg.username, user, sizeof(cfg.username) - 1);
	cfg.username[sizeof(cfg.username) - 1] = '\0';
    } else if (cfg.username[0] == '\0') {
	namelen = 0;
	if (GetUserName(user, &namelen) == FALSE)
	    bump("Empty user name");
	user = smalloc(namelen * sizeof(char));
	GetUserName(user, &namelen);
	if (verbose)
	    tell_user(stderr, "Guessing user name: %s", user);
	strncpy(cfg.username, user, sizeof(cfg.username) - 1);
	cfg.username[sizeof(cfg.username) - 1] = '\0';
	free(user);
    }

    if (cfg.protocol != PROT_SSH)
	cfg.port = 22;

    if (portnumber)
	cfg.port = portnumber;

    /*
     * Disable scary things which shouldn't be enabled for simple
     * things like SCP and SFTP: agent forwarding, port forwarding,
     * X forwarding.
     */
    cfg.x11_forward = 0;
    cfg.agentfwd = 0;
    cfg.portfwd[0] = cfg.portfwd[1] = '\0';

    /*
     * Attempt to start the SFTP subsystem as a first choice,
     * falling back to the provided scp command if that fails.
     */
    strcpy(cfg.remote_cmd, "sftp");
    cfg.ssh_subsys = TRUE;
    cfg.remote_cmd_ptr2 = cmd;
    cfg.ssh_subsys2 = FALSE;
    cfg.nopty = TRUE;

    back = &ssh_backend;

    err = back->init(cfg.host, cfg.port, &realhost, 0);
    if (err != NULL)
	bump("ssh_init: %s", err);
    ssh_scp_init();
    if (verbose && realhost != NULL)
	tell_user(stderr, "Connected to %s\n", realhost);
    sfree(realhost);
}

/*
 *  Update statistic information about current file.
 */
static void print_stats(char *name, unsigned long size, unsigned long done,
			time_t start, time_t now)
{
    float ratebs;
    unsigned long eta;
    char etastr[10];
    int pct;
    int len;
    int elap;

    elap = (unsigned long) difftime(now, start);

    if (now > start)
	ratebs = (float) done / elap;
    else
	ratebs = (float) done;

    if (ratebs < 1.0)
	eta = size - done;
    else
	eta = (unsigned long) ((size - done) / ratebs);
    sprintf(etastr, "%02ld:%02ld:%02ld",
	    eta / 3600, (eta % 3600) / 60, eta % 60);

    pct = (int) (100 * (done * 1.0 / size));

    if (gui_mode)
	/* GUI Adaptation - Sept 2000 */
	gui_update_stats(name, size, pct, elap, done, eta, 
			 (unsigned long) ratebs);
    else {
	len = printf("\r%-25.25s | %10ld kB | %5.1f kB/s | ETA: %8s | %3d%%",
		     name, done / 1024, ratebs / 1024.0, etastr, pct);
	if (len < prev_stats_len)
	    printf("%*s", prev_stats_len - len, "");
	prev_stats_len = len;

	if (done == size)
	    printf("\n");
    }
}

/*
 *  Find a colon in str and return a pointer to the colon.
 *  This is used to separate hostname from filename.
 */
static char *colon(char *str)
{
    /* We ignore a leading colon, since the hostname cannot be
       empty. We also ignore a colon as second character because
       of filenames like f:myfile.txt. */
    if (str[0] == '\0' || str[0] == ':' || str[1] == ':')
	return (NULL);
    while (*str != '\0' && *str != ':' && *str != '/' && *str != '\\')
	str++;
    if (*str == ':')
	return (str);
    else
	return (NULL);
}

/*
 * Return a pointer to the portion of str that comes after the last
 * slash (or backslash or colon, if `local' is TRUE).
 */
static char *stripslashes(char *str, int local)
{
    char *p;

    if (local) {
        p = strchr(str, ':');
        if (p) str = p+1;
    }

    p = strrchr(str, '/');
    if (p) str = p+1;

    if (local) {
	p = strrchr(str, '\\');
	if (p) str = p+1;
    }

    return str;
}

/*
 * Determine whether a string is entirely composed of dots.
 */
static int is_dots(char *str)
{
    return str[strspn(str, ".")] == '\0';
}

/*
 *  Wait for a response from the other side.
 *  Return 0 if ok, -1 if error.
 */
static int response(void)
{
    char ch, resp, rbuf[2048];
    int p;

    if (ssh_scp_recv(&resp, 1) <= 0)
	bump("Lost connection");

    p = 0;
    switch (resp) {
      case 0:			       /* ok */
	return (0);
      default:
	rbuf[p++] = resp;
	/* fallthrough */
      case 1:			       /* error */
      case 2:			       /* fatal error */
	do {
	    if (ssh_scp_recv(&ch, 1) <= 0)
		bump("Protocol error: Lost connection");
	    rbuf[p++] = ch;
	} while (p < sizeof(rbuf) && ch != '\n');
	rbuf[p - 1] = '\0';
	if (resp == 1)
	    tell_user(stderr, "%s\n", rbuf);
	else
	    bump("%s", rbuf);
	errs++;
	return (-1);
    }
}

int sftp_recvdata(char *buf, int len)
{
    return ssh_scp_recv(buf, len);
}
int sftp_senddata(char *buf, int len)
{
    back->send((unsigned char *) buf, len);
    return 1;
}

/* ----------------------------------------------------------------------
 * sftp-based replacement for the hacky `pscp -ls'.
 */
static int sftp_ls_compare(const void *av, const void *bv)
{
    const struct fxp_name *a = (const struct fxp_name *) av;
    const struct fxp_name *b = (const struct fxp_name *) bv;
    return strcmp(a->filename, b->filename);
}
void scp_sftp_listdir(char *dirname)
{
    struct fxp_handle *dirh;
    struct fxp_names *names;
    struct fxp_name *ournames;
    int nnames, namesize;
    int i;

    if (!fxp_init()) {
	tell_user(stderr, "unable to initialise SFTP: %s", fxp_error());
	errs++;
	return;
    }

    printf("Listing directory %s\n", dirname);

    dirh = fxp_opendir(dirname);
    if (dirh == NULL) {
	printf("Unable to open %s: %s\n", dirname, fxp_error());
    } else {
	nnames = namesize = 0;
	ournames = NULL;

	while (1) {

	    names = fxp_readdir(dirh);
	    if (names == NULL) {
		if (fxp_error_type() == SSH_FX_EOF)
		    break;
		printf("Reading directory %s: %s\n", dirname, fxp_error());
		break;
	    }
	    if (names->nnames == 0) {
		fxp_free_names(names);
		break;
	    }

	    if (nnames + names->nnames >= namesize) {
		namesize += names->nnames + 128;
		ournames =
		    srealloc(ournames, namesize * sizeof(*ournames));
	    }

	    for (i = 0; i < names->nnames; i++)
		ournames[nnames++] = names->names[i];

	    names->nnames = 0;	       /* prevent free_names */
	    fxp_free_names(names);
	}
	fxp_close(dirh);

	/*
	 * Now we have our filenames. Sort them by actual file
	 * name, and then output the longname parts.
	 */
	qsort(ournames, nnames, sizeof(*ournames), sftp_ls_compare);

	/*
	 * And print them.
	 */
	for (i = 0; i < nnames; i++)
	    printf("%s\n", ournames[i].longname);
    }
}

/* ----------------------------------------------------------------------
 * Helper routines that contain the actual SCP protocol elements,
 * implemented both as SCP1 and SFTP.
 */

static struct scp_sftp_dirstack {
    struct scp_sftp_dirstack *next;
    struct fxp_name *names;
    int namepos, namelen;
    char *dirpath;
    char *wildcard;
    int matched_something;	       /* wildcard match set was non-empty */
} *scp_sftp_dirstack_head;
static char *scp_sftp_remotepath, *scp_sftp_currentname;
static char *scp_sftp_wildcard;
static int scp_sftp_targetisdir, scp_sftp_donethistarget;
static int scp_sftp_preserve, scp_sftp_recursive;
static unsigned long scp_sftp_mtime, scp_sftp_atime;
static int scp_has_times;
static struct fxp_handle *scp_sftp_filehandle;
static uint64 scp_sftp_fileoffset;

void scp_source_setup(char *target, int shouldbedir)
{
    if (using_sftp) {
	/*
	 * Find out whether the target filespec is in fact a
	 * directory.
	 */
	struct fxp_attrs attrs;

	if (!fxp_init()) {
	    tell_user(stderr, "unable to initialise SFTP: %s", fxp_error());
	    errs++;
	    return 1;
	}

	if (!fxp_stat(target, &attrs) ||
	    !(attrs.flags & SSH_FILEXFER_ATTR_PERMISSIONS))
	    scp_sftp_targetisdir = 0;
	else
	    scp_sftp_targetisdir = (attrs.permissions & 0040000) != 0;

	if (shouldbedir && !scp_sftp_targetisdir) {
	    bump("pscp: remote filespec %s: not a directory\n", target);
	}

	scp_sftp_remotepath = dupstr(target);

	scp_has_times = 0;
    } else {
	(void) response();
    }
}

int scp_send_errmsg(char *str)
{
    if (using_sftp) {
	/* do nothing; we never need to send our errors to the server */
    } else {
	back->send("\001", 1);	       /* scp protocol error prefix */
	back->send(str, strlen(str));
    }
    return 0;			       /* can't fail */
}

int scp_send_filetimes(unsigned long mtime, unsigned long atime)
{
    if (using_sftp) {
	scp_sftp_mtime = mtime;
	scp_sftp_atime = atime;
	scp_has_times = 1;
	return 0;
    } else {
	char buf[80];
	sprintf(buf, "T%lu 0 %lu 0\n", mtime, atime);
	back->send(buf, strlen(buf));
	return response();
    }
}

int scp_send_filename(char *name, unsigned long size, int modes)
{
    if (using_sftp) {
	char *fullname;
	if (scp_sftp_targetisdir) {
	    fullname = dupcat(scp_sftp_remotepath, "/", name, NULL);
	} else {
	    fullname = dupstr(scp_sftp_remotepath);
	}
	scp_sftp_filehandle =
	    fxp_open(fullname, SSH_FXF_WRITE | SSH_FXF_CREAT | SSH_FXF_TRUNC);
	if (!scp_sftp_filehandle) {
	    tell_user(stderr, "pscp: unable to open %s: %s",
		      fullname, fxp_error());
	    errs++;
	    return 1;
	}
	scp_sftp_fileoffset = uint64_make(0, 0);
	sfree(fullname);
	return 0;
    } else {
	char buf[40];
	sprintf(buf, "C%04o %lu ", modes, size);
	back->send(buf, strlen(buf));
	back->send(name, strlen(name));
	back->send("\n", 1);
	return response();
    }
}

int scp_send_filedata(char *data, int len)
{
    if (using_sftp) {
	if (!scp_sftp_filehandle) {
	    return 1;
	}
	if (!fxp_write(scp_sftp_filehandle, data, scp_sftp_fileoffset, len)) {
	    tell_user(stderr, "error while writing: %s\n", fxp_error());
	    errs++;
	    return 1;
	}
	scp_sftp_fileoffset = uint64_add32(scp_sftp_fileoffset, len);
	return 0;
    } else {
	int bufsize = back->send(data, len);

	/*
	 * If the network transfer is backing up - that is, the
	 * remote site is not accepting data as fast as we can
	 * produce it - then we must loop on network events until
	 * we have space in the buffer again.
	 */
	while (bufsize > MAX_SCP_BUFSIZE) {
	    if (!scp_process_network_event())
		return 1;
	    bufsize = back->sendbuffer();
	}

	return 0;
    }
}

int scp_send_finish(void)
{
    if (using_sftp) {
	struct fxp_attrs attrs;
	if (!scp_sftp_filehandle) {
	    return 1;
	}
	if (scp_has_times) {
	    attrs.flags = SSH_FILEXFER_ATTR_ACMODTIME;
	    attrs.atime = scp_sftp_atime;
	    attrs.mtime = scp_sftp_mtime;
	    if (!fxp_fsetstat(scp_sftp_filehandle, attrs)) {
		tell_user(stderr, "unable to set file times: %s\n", fxp_error());
		errs++;
	    }
	}
	fxp_close(scp_sftp_filehandle);
	scp_has_times = 0;
	return 0;
    } else {
	back->send("", 1);
	return response();
    }
}

char *scp_save_remotepath(void)
{
    if (using_sftp)
	return scp_sftp_remotepath;
    else
	return NULL;
}

void scp_restore_remotepath(char *data)
{
    if (using_sftp)
	scp_sftp_remotepath = data;
}

int scp_send_dirname(char *name, int modes)
{
    if (using_sftp) {
	char *fullname;
	char const *err;
	struct fxp_attrs attrs;
	if (scp_sftp_targetisdir) {
	    fullname = dupcat(scp_sftp_remotepath, "/", name, NULL);
	} else {
	    fullname = dupstr(scp_sftp_remotepath);
	}

	/*
	 * We don't worry about whether we managed to create the
	 * directory, because if it exists already it's OK just to
	 * use it. Instead, we will stat it afterwards, and if it
	 * exists and is a directory we will assume we were either
	 * successful or it didn't matter.
	 */
	if (!fxp_mkdir(fullname))
	    err = fxp_error();
	else
	    err = "server reported no error";
	if (!fxp_stat(fullname, &attrs) ||
	    !(attrs.flags & SSH_FILEXFER_ATTR_PERMISSIONS) ||
	    !(attrs.permissions & 0040000)) {
	    tell_user(stderr, "unable to create directory %s: %s",
		      fullname, err);
	    errs++;
	    return 1;
	}

	scp_sftp_remotepath = fullname;

	return 0;
    } else {
	char buf[40];
	sprintf(buf, "D%04o 0 ", modes);
	back->send(buf, strlen(buf));
	back->send(name, strlen(name));
	back->send("\n", 1);
	return response();
    }
}

int scp_send_enddir(void)
{
    if (using_sftp) {
	sfree(scp_sftp_remotepath);
	return 0;
    } else {
	back->send("E\n", 2);
	return response();
    }
}

/*
 * Yes, I know; I have an scp_sink_setup _and_ an scp_sink_init.
 * That's bad. The difference is that scp_sink_setup is called once
 * right at the start, whereas scp_sink_init is called to
 * initialise every level of recursion in the protocol.
 */
int scp_sink_setup(char *source, int preserve, int recursive)
{
    if (using_sftp) {
	char *newsource;

	if (!fxp_init()) {
	    tell_user(stderr, "unable to initialise SFTP: %s", fxp_error());
	    errs++;
	    return 1;
	}
	/*
	 * It's possible that the source string we've been given
	 * contains a wildcard. If so, we must split the directory
	 * away from the wildcard itself (throwing an error if any
	 * wildcardness comes before the final slash) and arrange
	 * things so that a dirstack entry will be set up.
	 */
	newsource = smalloc(1+strlen(source));
	if (!wc_unescape(newsource, source)) {
	    /* Yes, here we go; it's a wildcard. Bah. */
	    char *dupsource, *lastpart, *dirpart, *wildcard;
	    dupsource = dupstr(source);
	    lastpart = stripslashes(dupsource, 0);
	    wildcard = dupstr(lastpart);
	    *lastpart = '\0';
	    if (*dupsource && dupsource[1]) {
		/*
		 * The remains of dupsource are at least two
		 * characters long, meaning the pathname wasn't
		 * empty or just `/'. Hence, we remove the trailing
		 * slash.
		 */
		lastpart[-1] = '\0';
	    } else if (!*dupsource) {
		/*
		 * The remains of dupsource are _empty_ - the whole
		 * pathname was a wildcard. Hence we need to
		 * replace it with ".".
		 */
		sfree(dupsource);
		dupsource = dupstr(".");
	    }

	    /*
	     * Now we have separated our string into dupsource (the
	     * directory part) and wildcard. Both of these will
	     * need freeing at some point. Next step is to remove
	     * wildcard escapes from the directory part, throwing
	     * an error if it contains a real wildcard.
	     */
	    dirpart = smalloc(1+strlen(dupsource));
	    if (!wc_unescape(dirpart, dupsource)) {
		tell_user(stderr, "%s: multiple-level wildcards unsupported",
			  source);
		errs++;
		sfree(dirpart);
		sfree(wildcard);
		sfree(dupsource);
		return 1;
	    }

	    /*
	     * Now we have dirpart (unescaped, ie a valid remote
	     * path), and wildcard (a wildcard). This will be
	     * sufficient to arrange a dirstack entry.
	     */
	    scp_sftp_remotepath = dirpart;
	    scp_sftp_wildcard = wildcard;
	    sfree(dupsource);
	} else {
	    scp_sftp_remotepath = newsource;
	    scp_sftp_wildcard = NULL;
	}
	scp_sftp_preserve = preserve;
	scp_sftp_recursive = recursive;
	scp_sftp_donethistarget = 0;
	scp_sftp_dirstack_head = NULL;
    }
    return 0;
}

int scp_sink_init(void)
{
    if (!using_sftp) {
	back->send("", 1);
    }
    return 0;
}

#define SCP_SINK_FILE   1
#define SCP_SINK_DIR    2
#define SCP_SINK_ENDDIR 3
#define SCP_SINK_RETRY  4	       /* not an action; just try again */
struct scp_sink_action {
    int action;			       /* FILE, DIR, ENDDIR */
    char *buf;			       /* will need freeing after use */
    char *name;			       /* filename or dirname (not ENDDIR) */
    int mode;			       /* access mode (not ENDDIR) */
    unsigned long size;		       /* file size (not ENDDIR) */
    int settime;		       /* 1 if atime and mtime are filled */
    unsigned long atime, mtime;	       /* access times for the file */
};

int scp_get_sink_action(struct scp_sink_action *act)
{
    if (using_sftp) {
	char *fname;
	int must_free_fname;
	struct fxp_attrs attrs;
	int ret;

	if (!scp_sftp_dirstack_head) {
	    if (!scp_sftp_donethistarget) {
		/*
		 * Simple case: we are only dealing with one file.
		 */
		fname = scp_sftp_remotepath;
		must_free_fname = 0;
		scp_sftp_donethistarget = 1;
	    } else {
		/*
		 * Even simpler case: one file _which we've done_.
		 * Return 1 (finished).
		 */
		return 1;
	    }
	} else {
	    /*
	     * We're now in the middle of stepping through a list
	     * of names returned from fxp_readdir(); so let's carry
	     * on.
	     */
	    struct scp_sftp_dirstack *head = scp_sftp_dirstack_head;
	    while (head->namepos < head->namelen &&
		   (is_dots(head->names[head->namepos].filename) ||
		    (head->wildcard &&
		     !wc_match(head->wildcard,
			       head->names[head->namepos].filename))))
		head->namepos++;       /* skip . and .. */
	    if (head->namepos < head->namelen) {
		head->matched_something = 1;
		fname = dupcat(head->dirpath, "/",
			       head->names[head->namepos++].filename,
			       NULL);
		must_free_fname = 1;
	    } else {
		/*
		 * We've come to the end of the list; pop it off
		 * the stack and return an ENDDIR action (or RETRY
		 * if this was a wildcard match).
		 */
		if (head->wildcard) {
		    act->action = SCP_SINK_RETRY;
		    if (!head->matched_something) {
			tell_user(stderr, "pscp: wildcard '%s' matched "
				  "no files", head->wildcard);
			errs++;
		    }
		    sfree(head->wildcard);

		} else {
		    act->action = SCP_SINK_ENDDIR;
		}

		sfree(head->dirpath);
		sfree(head->names);
		scp_sftp_dirstack_head = head->next;
		sfree(head);

		return 0;
	    }
	}

	/*
	 * Now we have a filename. Stat it, and see if it's a file
	 * or a directory.
	 */
	ret = fxp_stat(fname, &attrs);
	if (!ret || !(attrs.flags & SSH_FILEXFER_ATTR_PERMISSIONS)) {
	    tell_user(stderr, "unable to identify %s: %s", fname,
		      ret ? "file type not supplied" : fxp_error());
	    errs++;
	    return 1;
	}

	if (attrs.permissions & 0040000) {
	    struct scp_sftp_dirstack *newitem;
	    struct fxp_handle *dirhandle;
	    int nnames, namesize;
	    struct fxp_name *ournames;
	    struct fxp_names *names;

	    /*
	     * It's a directory. If we're not in recursive mode,
	     * this merits a complaint (which is fatal if the name
	     * was specified directly, but not if it was matched by
	     * a wildcard).
	     * 
	     * We skip this complaint completely if
	     * scp_sftp_wildcard is set, because that's an
	     * indication that we're not actually supposed to
	     * _recursively_ transfer the dir, just scan it for
	     * things matching the wildcard.
	     */
	    if (!scp_sftp_recursive && !scp_sftp_wildcard) {
		tell_user(stderr, "pscp: %s: is a directory", fname);
		errs++;
		if (must_free_fname) sfree(fname);
		if (scp_sftp_dirstack_head) {
		    act->action = SCP_SINK_RETRY;
		    return 0;
		} else {
		    return 1;
		}
	    }

	    /*
	     * Otherwise, the fun begins. We must fxp_opendir() the
	     * directory, slurp the filenames into memory, return
	     * SCP_SINK_DIR (unless this is a wildcard match), and
	     * set targetisdir. The next time we're called, we will
	     * run through the list of filenames one by one,
	     * matching them against a wildcard if present.
	     * 
	     * If targetisdir is _already_ set (meaning we're
	     * already in the middle of going through another such
	     * list), we must push the other (target,namelist) pair
	     * on a stack.
	     */
	    dirhandle = fxp_opendir(fname);
	    if (!dirhandle) {
		tell_user(stderr, "scp: unable to open directory %s: %s",
			  fname, fxp_error());
		if (must_free_fname) sfree(fname);
		errs++;
		return 1;
	    }
	    nnames = namesize = 0;
	    ournames = NULL;
	    while (1) {
		int i;

		names = fxp_readdir(dirhandle);
		if (names == NULL) {
		    if (fxp_error_type() == SSH_FX_EOF)
			break;
		    tell_user(stderr, "scp: reading directory %s: %s\n",
			      fname, fxp_error());
		    if (must_free_fname) sfree(fname);
		    sfree(ournames);
		    errs++;
		    return 1;
		}
		if (names->nnames == 0) {
		    fxp_free_names(names);
		    break;
		}
		if (nnames + names->nnames >= namesize) {
		    namesize += names->nnames + 128;
		    ournames =
			srealloc(ournames, namesize * sizeof(*ournames));
		}
		for (i = 0; i < names->nnames; i++)
		    ournames[nnames++] = names->names[i];
		names->nnames = 0;	       /* prevent free_names */
		fxp_free_names(names);
	    }
	    fxp_close(dirhandle);

	    newitem = smalloc(sizeof(struct scp_sftp_dirstack));
	    newitem->next = scp_sftp_dirstack_head;
	    newitem->names = ournames;
	    newitem->namepos = 0;
	    newitem->namelen = nnames;
	    if (must_free_fname)
		newitem->dirpath = fname;
	    else
		newitem->dirpath = dupstr(fname);
	    if (scp_sftp_wildcard) {
		newitem->wildcard = scp_sftp_wildcard;
		newitem->matched_something = 0;
		scp_sftp_wildcard = NULL;
	    } else {
		newitem->wildcard = NULL;
	    }
	    scp_sftp_dirstack_head = newitem;

	    if (newitem->wildcard) {
		act->action = SCP_SINK_RETRY;
	    } else {
		act->action = SCP_SINK_DIR;
		act->buf = dupstr(stripslashes(fname, 0));
		act->name = act->buf;
		act->size = 0;	       /* duhh, it's a directory */
		act->mode = 07777 & attrs.permissions;
		if (scp_sftp_preserve &&
		    (attrs.flags & SSH_FILEXFER_ATTR_ACMODTIME)) {
		    act->atime = attrs.atime;
		    act->mtime = attrs.mtime;
		    act->settime = 1;
		} else
		    act->settime = 0;
	    }
	    return 0;

	} else {
	    /*
	     * It's a file. Return SCP_SINK_FILE.
	     */
	    act->action = SCP_SINK_FILE;
	    act->buf = dupstr(stripslashes(fname, 0));
	    act->name = act->buf;
	    if (attrs.flags & SSH_FILEXFER_ATTR_SIZE) {
		if (uint64_compare(attrs.size,
				   uint64_make(0, ULONG_MAX)) > 0) {
		    act->size = ULONG_MAX;   /* *boggle* */
		} else
		    act->size = attrs.size.lo;
	    } else
		act->size = ULONG_MAX;   /* no idea */
	    act->mode = 07777 & attrs.permissions;
	    if (scp_sftp_preserve &&
		(attrs.flags & SSH_FILEXFER_ATTR_ACMODTIME)) {
		act->atime = attrs.atime;
		act->mtime = attrs.mtime;
		act->settime = 1;
	    } else
		act->settime = 0;
	    if (must_free_fname)
		scp_sftp_currentname = fname;
	    else
		scp_sftp_currentname = dupstr(fname);
	    return 0;
	}

    } else {
	int done = 0;
	int i, bufsize;
	int action;
	char ch;

	act->settime = 0;
	act->buf = NULL;
	bufsize = 0;

	while (!done) {
	    if (ssh_scp_recv(&ch, 1) <= 0)
		return 1;
	    if (ch == '\n')
		bump("Protocol error: Unexpected newline");
	    i = 0;
	    action = ch;
	    do {
		if (ssh_scp_recv(&ch, 1) <= 0)
		    bump("Lost connection");
		if (i >= bufsize) {
		    bufsize = i + 128;
		    act->buf = srealloc(act->buf, bufsize);
		}
		act->buf[i++] = ch;
	    } while (ch != '\n');
	    act->buf[i - 1] = '\0';
	    switch (action) {
	      case '\01':		       /* error */
		tell_user(stderr, "%s\n", act->buf);
		errs++;
		continue;		       /* go round again */
	      case '\02':		       /* fatal error */
		bump("%s", act->buf);
	      case 'E':
		back->send("", 1);
		act->action = SCP_SINK_ENDDIR;
		return 0;
	      case 'T':
		if (sscanf(act->buf, "%ld %*d %ld %*d",
			   &act->mtime, &act->atime) == 2) {
		    act->settime = 1;
		    back->send("", 1);
		    continue;	       /* go round again */
		}
		bump("Protocol error: Illegal time format");
	      case 'C':
	      case 'D':
		act->action = (action == 'C' ? SCP_SINK_FILE : SCP_SINK_DIR);
		break;
	      default:
		bump("Protocol error: Expected control record");
	    }
	    /*
	     * We will go round this loop only once, unless we hit
	     * `continue' above.
	     */
	    done = 1;
	}

	/*
	 * If we get here, we must have seen SCP_SINK_FILE or
	 * SCP_SINK_DIR.
	 */
	if (sscanf(act->buf, "%o %lu %n", &act->mode, &act->size, &i) != 2)
	    bump("Protocol error: Illegal file descriptor format");
	act->name = act->buf + i;
	return 0;
    }
}

int scp_accept_filexfer(void)
{
    if (using_sftp) {
	scp_sftp_filehandle =
	    fxp_open(scp_sftp_currentname, SSH_FXF_READ);
	if (!scp_sftp_filehandle) {
	    tell_user(stderr, "pscp: unable to open %s: %s",
		      scp_sftp_currentname, fxp_error());
	    errs++;
	    return 1;
	}
	scp_sftp_fileoffset = uint64_make(0, 0);
	sfree(scp_sftp_currentname);
	return 0;
    } else {
	back->send("", 1);
	return 0;		       /* can't fail */
    }
}

int scp_recv_filedata(char *data, int len)
{
    if (using_sftp) {
	int actuallen = fxp_read(scp_sftp_filehandle, data,
				 scp_sftp_fileoffset, len);
	if (actuallen == -1 && fxp_error_type() != SSH_FX_EOF) {
	    tell_user(stderr, "pscp: error while reading: %s", fxp_error());
	    errs++;
	    return -1;
	}
	if (actuallen < 0)
	    actuallen = 0;

	scp_sftp_fileoffset = uint64_add32(scp_sftp_fileoffset, actuallen);

	return actuallen;
    } else {
	return ssh_scp_recv(data, len);
    }
}

int scp_finish_filerecv(void)
{
    if (using_sftp) {
	fxp_close(scp_sftp_filehandle);
	return 0;
    } else {
	back->send("", 1);
	return response();
    }
}

/* ----------------------------------------------------------------------
 *  Send an error message to the other side and to the screen.
 *  Increment error counter.
 */
static void run_err(const char *fmt, ...)
{
    char str[2048];
    va_list ap;
    va_start(ap, fmt);
    errs++;
    strcpy(str, "scp: ");
    vsprintf(str + strlen(str), fmt, ap);
    strcat(str, "\n");
    scp_send_errmsg(str);
    tell_user(stderr, "%s", str);
    va_end(ap);
}

/*
 *  Execute the source part of the SCP protocol.
 */
static void source(char *src)
{
    unsigned long size;
    char *last;
    HANDLE f;
    DWORD attr;
    unsigned long i;
    unsigned long stat_bytes;
    time_t stat_starttime, stat_lasttime;

    attr = GetFileAttributes(src);
    if (attr == (DWORD) - 1) {
	run_err("%s: No such file or directory", src);
	return;
    }

    if ((attr & FILE_ATTRIBUTE_DIRECTORY) != 0) {
	if (recursive) {
	    /*
	     * Avoid . and .. directories.
	     */
	    char *p;
	    p = strrchr(src, '/');
	    if (!p)
		p = strrchr(src, '\\');
	    if (!p)
		p = src;
	    else
		p++;
	    if (!strcmp(p, ".") || !strcmp(p, ".."))
		/* skip . and .. */ ;
	    else
		rsource(src);
	} else {
	    run_err("%s: not a regular file", src);
	}
	return;
    }

    if ((last = strrchr(src, '/')) == NULL)
	last = src;
    else
	last++;
    if (strrchr(last, '\\') != NULL)
	last = strrchr(last, '\\') + 1;
    if (last == src && strchr(src, ':') != NULL)
	last = strchr(src, ':') + 1;

    f = CreateFile(src, GENERIC_READ, FILE_SHARE_READ, NULL,
		   OPEN_EXISTING, 0, 0);
    if (f == INVALID_HANDLE_VALUE) {
	run_err("%s: Cannot open file", src);
	return;
    }

    if (preserve) {
	FILETIME actime, wrtime;
	unsigned long mtime, atime;
	GetFileTime(f, NULL, &actime, &wrtime);
	TIME_WIN_TO_POSIX(actime, atime);
	TIME_WIN_TO_POSIX(wrtime, mtime);
	if (scp_send_filetimes(mtime, atime))
	    return;
    }

    size = GetFileSize(f, NULL);
    if (verbose)
	tell_user(stderr, "Sending file %s, size=%lu", last, size);
    if (scp_send_filename(last, size, 0644))
	return;

    stat_bytes = 0;
    stat_starttime = time(NULL);
    stat_lasttime = 0;

    for (i = 0; i < size; i += 4096) {
	char transbuf[4096];
	DWORD j, k = 4096;

	if (i + k > size)
	    k = size - i;
	if (!ReadFile(f, transbuf, k, &j, NULL) || j != k) {
	    if (statistics)
		printf("\n");
	    bump("%s: Read error", src);
	}
	if (scp_send_filedata(transbuf, k))
	    bump("%s: Network error occurred", src);

	if (statistics) {
	    stat_bytes += k;
	    if (time(NULL) != stat_lasttime || i + k == size) {
		stat_lasttime = time(NULL);
		print_stats(last, size, stat_bytes,
			    stat_starttime, stat_lasttime);
	    }
	}

    }
    CloseHandle(f);

    (void) scp_send_finish();
}

/*
 *  Recursively send the contents of a directory.
 */
static void rsource(char *src)
{
    char *last, *findfile;
    char *save_target;
    HANDLE dir;
    WIN32_FIND_DATA fdat;
    int ok;

    if ((last = strrchr(src, '/')) == NULL)
	last = src;
    else
	last++;
    if (strrchr(last, '\\') != NULL)
	last = strrchr(last, '\\') + 1;
    if (last == src && strchr(src, ':') != NULL)
	last = strchr(src, ':') + 1;

    /* maybe send filetime */

    save_target = scp_save_remotepath();

    if (verbose)
	tell_user(stderr, "Entering directory: %s", last);
    if (scp_send_dirname(last, 0755))
	return;

    findfile = dupcat(src, "/*", NULL);
    dir = FindFirstFile(findfile, &fdat);
    ok = (dir != INVALID_HANDLE_VALUE);
    while (ok) {
	if (strcmp(fdat.cFileName, ".") == 0 ||
	    strcmp(fdat.cFileName, "..") == 0) {
	    /* ignore . and .. */
	} else {
	    char *foundfile = dupcat(src, "/", fdat.cFileName, NULL);
	    source(foundfile);
	    sfree(foundfile);
	}
	ok = FindNextFile(dir, &fdat);
    }
    FindClose(dir);
    sfree(findfile);

    (void) scp_send_enddir();

    scp_restore_remotepath(save_target);
}

/*
 * Execute the sink part of the SCP protocol.
 */
static void sink(char *targ, char *src)
{
    char *destfname;
    int targisdir = 0;
    int exists;
    DWORD attr;
    HANDLE f;
    unsigned long received;
    int wrerror = 0;
    unsigned long stat_bytes;
    time_t stat_starttime, stat_lasttime;
    char *stat_name;

    attr = GetFileAttributes(targ);
    if (attr != (DWORD) - 1 && (attr & FILE_ATTRIBUTE_DIRECTORY) != 0)
	targisdir = 1;

    if (targetshouldbedirectory && !targisdir)
	bump("%s: Not a directory", targ);

    scp_sink_init();
    while (1) {
	struct scp_sink_action act;
	if (scp_get_sink_action(&act))
	    return;

	if (act.action == SCP_SINK_ENDDIR)
	    return;

	if (act.action == SCP_SINK_RETRY)
	    continue;

	if (targisdir) {
	    /*
	     * Prevent the remote side from maliciously writing to
	     * files outside the target area by sending a filename
	     * containing `../'. In fact, it shouldn't be sending
	     * filenames with any slashes or colons in at all; so
	     * we'll find the last slash, backslash or colon in the
	     * filename and use only the part after that. (And
	     * warn!)
	     * 
	     * In addition, we also ensure here that if we're
	     * copying a single file and the target is a directory
	     * (common usage: `pscp host:filename .') the remote
	     * can't send us a _different_ file name. We can
	     * distinguish this case because `src' will be non-NULL
	     * and the last component of that will fail to match
	     * (the last component of) the name sent.
	     * 
	     * Well, not always; if `src' is a wildcard, we do
	     * expect to get back filenames that don't correspond
	     * exactly to it. Ideally in this case, we would like
	     * to ensure that the returned filename actually
	     * matches the wildcard pattern - but one of SCP's
	     * protocol infelicities is that wildcard matching is
	     * done at the server end _by the server's rules_ and
	     * so in general this is infeasible. Hence, we only
	     * accept filenames that don't correspond to `src' if
	     * unsafe mode is enabled or we are using SFTP (which
	     * resolves remote wildcards on the client side and can
	     * be trusted).
	     */
	    char *striptarget, *stripsrc;

	    striptarget = stripslashes(act.name, 1);
	    if (striptarget != act.name) {
		tell_user(stderr, "warning: remote host sent a compound"
			  " pathname '%s'", act.name);
		tell_user(stderr, "         renaming local file to '%s'",
                          striptarget);
	    }

	    /*
	     * Also check to see if the target filename is '.' or
	     * '..', or indeed '...' and so on because Windows
	     * appears to interpret those like '..'.
	     */
	    if (is_dots(striptarget)) {
		bump("security violation: remote host attempted to write to"
		     " a '.' or '..' path!");
	    }

	    if (src) {
		stripsrc = stripslashes(src, 1);
		if (strcmp(striptarget, stripsrc) &&
		    !using_sftp && !scp_unsafe_mode) {
		    tell_user(stderr, "warning: remote host tried to write "
			      "to a file called '%s'", striptarget);
		    tell_user(stderr, "         when we requested a file "
			      "called '%s'.", stripsrc);
		    tell_user(stderr, "         If this is a wildcard, "
			      "consider upgrading to SSH 2 or using");
		    tell_user(stderr, "         the '-unsafe' option. Renaming"
			      " of this file has been disallowed.");
		    /* Override the name the server provided with our own. */
		    striptarget = stripsrc;
		}
	    }

	    if (targ[0] != '\0')
		destfname = dupcat(targ, "\\", striptarget, NULL);
	    else
		destfname = dupstr(striptarget);
	} else {
	    /*
	     * In this branch of the if, the target area is a
	     * single file with an explicitly specified name in any
	     * case, so there's no danger.
	     */
	    destfname = dupstr(targ);
	}
	attr = GetFileAttributes(destfname);
	exists = (attr != (DWORD) - 1);

	if (act.action == SCP_SINK_DIR) {
	    if (exists && (attr & FILE_ATTRIBUTE_DIRECTORY) == 0) {
		run_err("%s: Not a directory", destfname);
		continue;
	    }
	    if (!exists) {
		if (!CreateDirectory(destfname, NULL)) {
		    run_err("%s: Cannot create directory", destfname);
		    continue;
		}
	    }
	    sink(destfname, NULL);
	    /* can we set the timestamp for directories ? */
	    continue;
	}

	f = CreateFile(destfname, GENERIC_WRITE, 0, NULL,
		       CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, 0);
	if (f == INVALID_HANDLE_VALUE) {
	    run_err("%s: Cannot create file", destfname);
	    continue;
	}

	if (scp_accept_filexfer())
	    return;

	stat_bytes = 0;
	stat_starttime = time(NULL);
	stat_lasttime = 0;
	stat_name = stripslashes(destfname, 1);

	received = 0;
	while (received < act.size) {
	    char transbuf[4096];
	    DWORD blksize, read, written;
	    blksize = 4096;
	    if (blksize > act.size - received)
		blksize = act.size - received;
	    read = scp_recv_filedata(transbuf, blksize);
	    if (read <= 0)
		bump("Lost connection");
	    if (wrerror)
		continue;
	    if (!WriteFile(f, transbuf, read, &written, NULL) ||
		written != read) {
		wrerror = 1;
		/* FIXME: in sftp we can actually abort the transfer */
		if (statistics)
		    printf("\r%-25.25s | %50s\n",
			   stat_name,
			   "Write error.. waiting for end of file");
		continue;
	    }
	    if (statistics) {
		stat_bytes += read;
		if (time(NULL) > stat_lasttime ||
		    received + read == act.size) {
		    stat_lasttime = time(NULL);
		    print_stats(stat_name, act.size, stat_bytes,
				stat_starttime, stat_lasttime);
		}
	    }
	    received += read;
	}
	if (act.settime) {
	    FILETIME actime, wrtime;
	    TIME_POSIX_TO_WIN(act.atime, actime);
	    TIME_POSIX_TO_WIN(act.mtime, wrtime);
	    SetFileTime(f, NULL, &actime, &wrtime);
	}

	CloseHandle(f);
	if (wrerror) {
	    run_err("%s: Write error", destfname);
	    continue;
	}
	(void) scp_finish_filerecv();
	sfree(destfname);
	sfree(act.buf);
    }
}

/*
 * We will copy local files to a remote server.
 */
static void toremote(int argc, char *argv[])
{
    char *src, *targ, *host, *user;
    char *cmd;
    int i;

    targ = argv[argc - 1];

    /* Separate host from filename */
    host = targ;
    targ = colon(targ);
    if (targ == NULL)
	bump("targ == NULL in toremote()");
    *targ++ = '\0';
    if (*targ == '\0')
	targ = ".";
    /* Substitute "." for emtpy target */

    /* Separate host and username */
    user = host;
    host = strrchr(host, '@');
    if (host == NULL) {
	host = user;
	user = NULL;
    } else {
	*host++ = '\0';
	if (*user == '\0')
	    user = NULL;
    }

    if (argc == 2) {
	/* Find out if the source filespec covers multiple files
	   if so, we should set the targetshouldbedirectory flag */
	HANDLE fh;
	WIN32_FIND_DATA fdat;
	if (colon(argv[0]) != NULL)
	    bump("%s: Remote to remote not supported", argv[0]);
	fh = FindFirstFile(argv[0], &fdat);
	if (fh == INVALID_HANDLE_VALUE)
	    bump("%s: No such file or directory\n", argv[0]);
	if (FindNextFile(fh, &fdat))
	    targetshouldbedirectory = 1;
	FindClose(fh);
    }

    cmd = smalloc(strlen(targ) + 100);
    sprintf(cmd, "scp%s%s%s%s -t %s",
	    verbose ? " -v" : "",
	    recursive ? " -r" : "",
	    preserve ? " -p" : "",
	    targetshouldbedirectory ? " -d" : "", targ);
    do_cmd(host, user, cmd);
    sfree(cmd);

    scp_source_setup(targ, targetshouldbedirectory);

    for (i = 0; i < argc - 1; i++) {
	char *srcpath, *last;
	HANDLE dir;
	WIN32_FIND_DATA fdat;
	src = argv[i];
	if (colon(src) != NULL) {
	    tell_user(stderr, "%s: Remote to remote not supported\n", src);
	    errs++;
	    continue;
	}

	/*
	 * Trim off the last pathname component of `src', to
	 * provide the base pathname which will be prepended to
	 * filenames returned from Find{First,Next}File.
	 */
	srcpath = dupstr(src);
	last = stripslashes(srcpath, 1);
	*last = '\0';

	dir = FindFirstFile(src, &fdat);
	if (dir == INVALID_HANDLE_VALUE) {
	    run_err("%s: No such file or directory", src);
	    continue;
	}
	do {
	    char *filename;
	    /*
	     * Ensure that . and .. are never matched by wildcards,
	     * but only by deliberate action.
	     */
	    if (!strcmp(fdat.cFileName, ".") ||
		!strcmp(fdat.cFileName, "..")) {
		/*
		 * Find*File has returned a special dir. We require
		 * that _either_ `src' ends in a backslash followed
		 * by that string, _or_ `src' is precisely that
		 * string.
		 */
		int len = strlen(src), dlen = strlen(fdat.cFileName);
		if (len == dlen && !strcmp(src, fdat.cFileName)) {
		    /* ok */ ;
		} else if (len > dlen + 1 && src[len - dlen - 1] == '\\' &&
			   !strcmp(src + len - dlen, fdat.cFileName)) {
		    /* ok */ ;
		} else
		    continue;	       /* ignore this one */
	    }
	    filename = dupcat(srcpath, fdat.cFileName, NULL);
	    source(filename);
	    sfree(filename);
	} while (FindNextFile(dir, &fdat));
	FindClose(dir);
	sfree(srcpath);
    }
}

/*
 *  We will copy files from a remote server to the local machine.
 */
static void tolocal(int argc, char *argv[])
{
    char *src, *targ, *host, *user;
    char *cmd;

    if (argc != 2)
	bump("More than one remote source not supported");

    src = argv[0];
    targ = argv[1];

    /* Separate host from filename */
    host = src;
    src = colon(src);
    if (src == NULL)
	bump("Local to local copy not supported");
    *src++ = '\0';
    if (*src == '\0')
	src = ".";
    /* Substitute "." for empty filename */

    /* Separate username and hostname */
    user = host;
    host = strrchr(host, '@');
    if (host == NULL) {
	host = user;
	user = NULL;
    } else {
	*host++ = '\0';
	if (*user == '\0')
	    user = NULL;
    }

    cmd = smalloc(strlen(src) + 100);
    sprintf(cmd, "scp%s%s%s%s -f %s",
	    verbose ? " -v" : "",
	    recursive ? " -r" : "",
	    preserve ? " -p" : "",
	    targetshouldbedirectory ? " -d" : "", src);
    do_cmd(host, user, cmd);
    sfree(cmd);

    if (scp_sink_setup(src, preserve, recursive))
	return;

    sink(targ, src);
}

/*
 *  We will issue a list command to get a remote directory.
 */
static void get_dir_list(int argc, char *argv[])
{
    char *src, *host, *user;
    char *cmd, *p, *q;
    char c;

    src = argv[0];

    /* Separate host from filename */
    host = src;
    src = colon(src);
    if (src == NULL)
	bump("Local to local copy not supported");
    *src++ = '\0';
    if (*src == '\0')
	src = ".";
    /* Substitute "." for empty filename */

    /* Separate username and hostname */
    user = host;
    host = strrchr(host, '@');
    if (host == NULL) {
	host = user;
	user = NULL;
    } else {
	*host++ = '\0';
	if (*user == '\0')
	    user = NULL;
    }

    cmd = smalloc(4 * strlen(src) + 100);
    strcpy(cmd, "ls -la '");
    p = cmd + strlen(cmd);
    for (q = src; *q; q++) {
	if (*q == '\'') {
	    *p++ = '\'';
	    *p++ = '\\';
	    *p++ = '\'';
	    *p++ = '\'';
	} else {
	    *p++ = *q;
	}
    }
    *p++ = '\'';
    *p = '\0';

    do_cmd(host, user, cmd);
    sfree(cmd);

    if (using_sftp) {
	scp_sftp_listdir(src);
    } else {
	while (ssh_scp_recv(&c, 1) > 0)
	    tell_char(stdout, c);
    }
}

/*
 *  Initialize the Win$ock driver.
 */
static void init_winsock(void)
{
    WORD winsock_ver;
    WSADATA wsadata;

    winsock_ver = MAKEWORD(1, 1);
    if (WSAStartup(winsock_ver, &wsadata))
	bump("Unable to initialise WinSock");
    if (LOBYTE(wsadata.wVersion) != 1 || HIBYTE(wsadata.wVersion) != 1)
	bump("WinSock version is incompatible with 1.1");
}

/*
 *  Short description of parameters.
 */
static void usage(void)
{
    printf("PuTTY Secure Copy client\n");
    printf("%s\n", ver);
    printf("Usage: pscp [options] [user@]host:source target\n");
    printf
	("       pscp [options] source [source...] [user@]host:target\n");
    printf("       pscp [options] -ls user@host:filespec\n");
    printf("Options:\n");
    printf("  -p        preserve file attributes\n");
    printf("  -q        quiet, don't show statistics\n");
    printf("  -r        copy directories recursively\n");
    printf("  -v        show verbose messages\n");
    printf("  -P port   connect to specified port\n");
    printf("  -pw passw login with specified password\n");
    printf("  -unsafe   allow server-side wildcards (DANGEROUS)\n");
#if 0
    /*
     * -gui is an internal option, used by GUI front ends to get
     * pscp to pass progress reports back to them. It's not an
     * ordinary user-accessible option, so it shouldn't be part of
     * the command-line help. The only people who need to know
     * about it are programmers, and they can read the source.
     */
    printf
	("  -gui hWnd GUI mode with the windows handle for receiving messages\n");
#endif
    cleanup_exit(1);
}

/*
 *  Main program (no, really?)
 */
int main(int argc, char *argv[])
{
    int i;

    default_protocol = PROT_TELNET;

    flags = FLAG_STDERR;
    ssh_get_line = &console_get_line;
    init_winsock();
    sk_init();

    for (i = 1; i < argc; i++) {
	if (argv[i][0] != '-')
	    break;
	if (strcmp(argv[i], "-v") == 0)
	    verbose = 1, flags |= FLAG_VERBOSE;
	else if (strcmp(argv[i], "-r") == 0)
	    recursive = 1;
	else if (strcmp(argv[i], "-p") == 0)
	    preserve = 1;
	else if (strcmp(argv[i], "-q") == 0)
	    statistics = 0;
	else if (strcmp(argv[i], "-batch") == 0)
	    console_batch_mode = 1;
	else if (strcmp(argv[i], "-h") == 0 || strcmp(argv[i], "-?") == 0)
	    usage();
	else if (strcmp(argv[i], "-P") == 0 && i + 1 < argc)
	    portnumber = atoi(argv[++i]);
	else if (strcmp(argv[i], "-pw") == 0 && i + 1 < argc)
	    console_password = argv[++i];
	else if (strcmp(argv[i], "-gui") == 0 && i + 1 < argc) {
	    gui_hwnd = argv[++i];
	    gui_mode = 1;
	    console_batch_mode = TRUE;
	} else if (strcmp(argv[i], "-ls") == 0)
	    list = 1;
	else if (strcmp(argv[i], "-unsafe") == 0)
	    scp_unsafe_mode = 1;
	else if (strcmp(argv[i], "--") == 0) {
	    i++;
	    break;
	} else
	    usage();
    }
    argc -= i;
    argv += i;
    back = NULL;

    if (list) {
	if (argc != 1)
	    usage();
	get_dir_list(argc, argv);

    } else {

	if (argc < 2)
	    usage();
	if (argc > 2)
	    targetshouldbedirectory = 1;

	if (colon(argv[argc - 1]) != NULL)
	    toremote(argc, argv);
	else
	    tolocal(argc, argv);
    }

    if (back != NULL && back->socket() != NULL) {
	char ch;
	back->special(TS_EOF);
	ssh_scp_recv(&ch, 1);
    }
    WSACleanup();
    random_save_seed();

    /* GUI Adaptation - August 2000 */
    if (gui_mode) {
	unsigned int msg_id = WM_RET_ERR_CNT;
	if (list)
	    msg_id = WM_LS_RET_ERR_CNT;
	while (!PostMessage
	       ((HWND) atoi(gui_hwnd), msg_id, (WPARAM) errs,
		0 /*lParam */ ))SleepEx(1000, TRUE);
    }
    return (errs == 0 ? 0 : 1);
}

/* end */