Fix culpable lack of generality in keyboard-interactive

[u/mdw/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 */