Return to scp.c CVS log

Up to [local] / src / usr.bin / ssh

Switch to recallocarray() for a few operations.  Both growth and shrinkage
are handled safely, and there also is no need for preallocation dances.
Future changes in this area will be less error prone.
Review and one bug found by markus

/* $OpenBSD: scp.c,v 1.192 2017/05/31 09:15:42 deraadt Exp $ */
/*
 * scp - secure remote copy.  This is basically patched BSD rcp which
 * uses ssh to do the data transfer (instead of using rcmd).
 *
 * NOTE: This version should NOT be suid root.  (This uses ssh to
 * do the transfer and ssh has the necessary privileges.)
 *
 * 1995 Timo Rinne <tri@iki.fi>, Tatu Ylonen <ylo@cs.hut.fi>
 *
 * As far as I am concerned, the code I have written for this software
 * can be used freely for any purpose.  Any derived versions of this
 * software must be clearly marked as such, and if the derived work is
 * incompatible with the protocol description in the RFC file, it must be
 * called by a name other than "ssh" or "Secure Shell".
 */
/*
 * Copyright (c) 1999 Theo de Raadt.  All rights reserved.
 * Copyright (c) 1999 Aaron Campbell.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Parts from:
 *
 * Copyright (c) 1983, 1990, 1992, 1993, 1995
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 */

#include <sys/types.h>
#include <sys/poll.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/uio.h>

#include <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <locale.h>
#include <pwd.h>
#include <signal.h>
#include <stdarg.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <limits.h>
#include <vis.h>

#include "xmalloc.h"
#include "atomicio.h"
#include "pathnames.h"
#include "log.h"
#include "misc.h"
#include "progressmeter.h"
#include "utf8.h"

#define COPY_BUFLEN	16384

int do_cmd(char *host, char *remuser, char *cmd, int *fdin, int *fdout);
int do_cmd2(char *host, char *remuser, char *cmd, int fdin, int fdout);

/* Struct for addargs */
arglist args;
arglist remote_remote_args;

/* Bandwidth limit */
long long limit_kbps = 0;
struct bwlimit bwlimit;

/* Name of current file being transferred. */
char *curfile;

/* This is set to non-zero to enable verbose mode. */
int verbose_mode = 0;

/* This is set to zero if the progressmeter is not desired. */
int showprogress = 1;

/*
 * This is set to non-zero if remote-remote copy should be piped
 * through this process.
 */
int throughlocal = 0;

/* This is the program to execute for the secured connection. ("ssh" or -S) */
char *ssh_program = _PATH_SSH_PROGRAM;

/* This is used to store the pid of ssh_program */
pid_t do_cmd_pid = -1;

static void
killchild(int signo)
{
	if (do_cmd_pid > 1) {
		kill(do_cmd_pid, signo ? signo : SIGTERM);
		waitpid(do_cmd_pid, NULL, 0);
	}

	if (signo)
		_exit(1);
	exit(1);
}

static void
suspchild(int signo)
{
	int status;

	if (do_cmd_pid > 1) {
		kill(do_cmd_pid, signo);
		while (waitpid(do_cmd_pid, &status, WUNTRACED) == -1 &&
		    errno == EINTR)
			;
		kill(getpid(), SIGSTOP);
	}
}

static int
do_local_cmd(arglist *a)
{
	u_int i;
	int status;
	pid_t pid;

	if (a->num == 0)
		fatal("do_local_cmd: no arguments");

	if (verbose_mode) {
		fprintf(stderr, "Executing:");
		for (i = 0; i < a->num; i++)
			fmprintf(stderr, " %s", a->list[i]);
		fprintf(stderr, "\n");
	}
	if ((pid = fork()) == -1)
		fatal("do_local_cmd: fork: %s", strerror(errno));

	if (pid == 0) {
		execvp(a->list[0], a->list);
		perror(a->list[0]);
		exit(1);
	}

	do_cmd_pid = pid;
	signal(SIGTERM, killchild);
	signal(SIGINT, killchild);
	signal(SIGHUP, killchild);

	while (waitpid(pid, &status, 0) == -1)
		if (errno != EINTR)
			fatal("do_local_cmd: waitpid: %s", strerror(errno));

	do_cmd_pid = -1;

	if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
		return (-1);

	return (0);
}

/*
 * This function executes the given command as the specified user on the
 * given host.  This returns < 0 if execution fails, and >= 0 otherwise. This
 * assigns the input and output file descriptors on success.
 */

int
do_cmd(char *host, char *remuser, char *cmd, int *fdin, int *fdout)
{
	int pin[2], pout[2], reserved[2];

	if (verbose_mode)
		fmprintf(stderr,
		    "Executing: program %s host %s, user %s, command %s\n",
		    ssh_program, host,
		    remuser ? remuser : "(unspecified)", cmd);

	/*
	 * Reserve two descriptors so that the real pipes won't get
	 * descriptors 0 and 1 because that will screw up dup2 below.
	 */
	if (pipe(reserved) < 0)
		fatal("pipe: %s", strerror(errno));

	/* Create a socket pair for communicating with ssh. */
	if (pipe(pin) < 0)
		fatal("pipe: %s", strerror(errno));
	if (pipe(pout) < 0)
		fatal("pipe: %s", strerror(errno));

	/* Free the reserved descriptors. */
	close(reserved[0]);
	close(reserved[1]);

	signal(SIGTSTP, suspchild);
	signal(SIGTTIN, suspchild);
	signal(SIGTTOU, suspchild);

	/* Fork a child to execute the command on the remote host using ssh. */
	do_cmd_pid = fork();
	if (do_cmd_pid == 0) {
		/* Child. */
		close(pin[1]);
		close(pout[0]);
		dup2(pin[0], 0);
		dup2(pout[1], 1);
		close(pin[0]);
		close(pout[1]);

		replacearg(&args, 0, "%s", ssh_program);
		if (remuser != NULL) {
			addargs(&args, "-l");
			addargs(&args, "%s", remuser);
		}
		addargs(&args, "--");
		addargs(&args, "%s", host);
		addargs(&args, "%s", cmd);

		execvp(ssh_program, args.list);
		perror(ssh_program);
		exit(1);
	} else if (do_cmd_pid == -1) {
		fatal("fork: %s", strerror(errno));
	}
	/* Parent.  Close the other side, and return the local side. */
	close(pin[0]);
	*fdout = pin[1];
	close(pout[1]);
	*fdin = pout[0];
	signal(SIGTERM, killchild);
	signal(SIGINT, killchild);
	signal(SIGHUP, killchild);
	return 0;
}

/*
 * This functions executes a command simlar to do_cmd(), but expects the
 * input and output descriptors to be setup by a previous call to do_cmd().
 * This way the input and output of two commands can be connected.
 */
int
do_cmd2(char *host, char *remuser, char *cmd, int fdin, int fdout)
{
	pid_t pid;
	int status;

	if (verbose_mode)
		fmprintf(stderr,
		    "Executing: 2nd program %s host %s, user %s, command %s\n",
		    ssh_program, host,
		    remuser ? remuser : "(unspecified)", cmd);

	/* Fork a child to execute the command on the remote host using ssh. */
	pid = fork();
	if (pid == 0) {
		dup2(fdin, 0);
		dup2(fdout, 1);

		replacearg(&args, 0, "%s", ssh_program);
		if (remuser != NULL) {
			addargs(&args, "-l");
			addargs(&args, "%s", remuser);
		}
		addargs(&args, "--");
		addargs(&args, "%s", host);
		addargs(&args, "%s", cmd);

		execvp(ssh_program, args.list);
		perror(ssh_program);
		exit(1);
	} else if (pid == -1) {
		fatal("fork: %s", strerror(errno));
	}
	while (waitpid(pid, &status, 0) == -1)
		if (errno != EINTR)
			fatal("do_cmd2: waitpid: %s", strerror(errno));
	return 0;
}

typedef struct {
	size_t cnt;
	char *buf;
} BUF;

BUF *allocbuf(BUF *, int, int);
void lostconn(int);
int okname(char *);
void run_err(const char *,...);
void verifydir(char *);

struct passwd *pwd;
uid_t userid;
int errs, remin, remout;
int pflag, iamremote, iamrecursive, targetshouldbedirectory;

#define	CMDNEEDS	64
char cmd[CMDNEEDS];		/* must hold "rcp -r -p -d\0" */

int response(void);
void rsource(char *, struct stat *);
void sink(int, char *[]);
void source(int, char *[]);
void tolocal(int, char *[]);
void toremote(char *, int, char *[]);
void usage(void);

int
main(int argc, char **argv)
{
	int ch, fflag, tflag, status, n;
	char *targ, **newargv;
	const char *errstr;
	extern char *optarg;
	extern int optind;

	/* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
	sanitise_stdfd();

	setlocale(LC_CTYPE, "");

	/* Copy argv, because we modify it */
	newargv = xcalloc(MAXIMUM(argc + 1, 1), sizeof(*newargv));
	for (n = 0; n < argc; n++)
		newargv[n] = xstrdup(argv[n]);
	argv = newargv;

	memset(&args, '\0', sizeof(args));
	memset(&remote_remote_args, '\0', sizeof(remote_remote_args));
	args.list = remote_remote_args.list = NULL;
	addargs(&args, "%s", ssh_program);
	addargs(&args, "-x");
	addargs(&args, "-oForwardAgent=no");
	addargs(&args, "-oPermitLocalCommand=no");
	addargs(&args, "-oClearAllForwardings=yes");

	fflag = tflag = 0;
	while ((ch = getopt(argc, argv, "dfl:prtvBCc:i:P:q12346S:o:F:")) != -1)
		switch (ch) {
		/* User-visible flags. */
		case '1':
			fatal("SSH protocol v.1 is no longer supported");
			break;
		case '2':
			/* Ignored */
			break;
		case '4':
		case '6':
		case 'C':
			addargs(&args, "-%c", ch);
			addargs(&remote_remote_args, "-%c", ch);
			break;
		case '3':
			throughlocal = 1;
			break;
		case 'o':
		case 'c':
		case 'i':
		case 'F':
			addargs(&remote_remote_args, "-%c", ch);
			addargs(&remote_remote_args, "%s", optarg);
			addargs(&args, "-%c", ch);
			addargs(&args, "%s", optarg);
			break;
		case 'P':
			addargs(&remote_remote_args, "-p");
			addargs(&remote_remote_args, "%s", optarg);
			addargs(&args, "-p");
			addargs(&args, "%s", optarg);
			break;
		case 'B':
			addargs(&remote_remote_args, "-oBatchmode=yes");
			addargs(&args, "-oBatchmode=yes");
			break;
		case 'l':
			limit_kbps = strtonum(optarg, 1, 100 * 1024 * 1024,
			    &errstr);
			if (errstr != NULL)
				usage();
			limit_kbps *= 1024; /* kbps */
			bandwidth_limit_init(&bwlimit, limit_kbps, COPY_BUFLEN);
			break;
		case 'p':
			pflag = 1;
			break;
		case 'r':
			iamrecursive = 1;
			break;
		case 'S':
			ssh_program = xstrdup(optarg);
			break;
		case 'v':
			addargs(&args, "-v");
			addargs(&remote_remote_args, "-v");
			verbose_mode = 1;
			break;
		case 'q':
			addargs(&args, "-q");
			addargs(&remote_remote_args, "-q");
			showprogress = 0;
			break;

		/* Server options. */
		case 'd':
			targetshouldbedirectory = 1;
			break;
		case 'f':	/* "from" */
			iamremote = 1;
			fflag = 1;
			break;
		case 't':	/* "to" */
			iamremote = 1;
			tflag = 1;
			break;
		default:
			usage();
		}
	argc -= optind;
	argv += optind;

	if ((pwd = getpwuid(userid = getuid())) == NULL)
		fatal("unknown user %u", (u_int) userid);

	if (!isatty(STDOUT_FILENO))
		showprogress = 0;

	if (pflag) {
		/* Cannot pledge: -p allows setuid/setgid files... */
	} else {
		if (pledge("stdio rpath wpath cpath fattr tty proc exec",
		    NULL) == -1) {
			perror("pledge");
			exit(1);
		}
	}

	remin = STDIN_FILENO;
	remout = STDOUT_FILENO;

	if (fflag) {
		/* Follow "protocol", send data. */
		(void) response();
		source(argc, argv);
		exit(errs != 0);
	}
	if (tflag) {
		/* Receive data. */
		sink(argc, argv);
		exit(errs != 0);
	}
	if (argc < 2)
		usage();
	if (argc > 2)
		targetshouldbedirectory = 1;

	remin = remout = -1;
	do_cmd_pid = -1;
	/* Command to be executed on remote system using "ssh". */
	(void) snprintf(cmd, sizeof cmd, "scp%s%s%s%s",
	    verbose_mode ? " -v" : "",
	    iamrecursive ? " -r" : "", pflag ? " -p" : "",
	    targetshouldbedirectory ? " -d" : "");

	(void) signal(SIGPIPE, lostconn);

	if ((targ = colon(argv[argc - 1])))	/* Dest is remote host. */
		toremote(targ, argc, argv);
	else {
		if (targetshouldbedirectory)
			verifydir(argv[argc - 1]);
		tolocal(argc, argv);	/* Dest is local host. */
	}
	/*
	 * Finally check the exit status of the ssh process, if one was forked
	 * and no error has occurred yet
	 */
	if (do_cmd_pid != -1 && errs == 0) {
		if (remin != -1)
		    (void) close(remin);
		if (remout != -1)
		    (void) close(remout);
		if (waitpid(do_cmd_pid, &status, 0) == -1)
			errs = 1;
		else {
			if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
				errs = 1;
		}
	}
	exit(errs != 0);
}

/* Callback from atomicio6 to update progress meter and limit bandwidth */
static int
scpio(void *_cnt, size_t s)
{
	off_t *cnt = (off_t *)_cnt;

	*cnt += s;
	if (limit_kbps > 0)
		bandwidth_limit(&bwlimit, s);
	return 0;
}

static int
do_times(int fd, int verb, const struct stat *sb)
{
	/* strlen(2^64) == 20; strlen(10^6) == 7 */
	char buf[(20 + 7 + 2) * 2 + 2];

	(void)snprintf(buf, sizeof(buf), "T%llu 0 %llu 0\n",
	    (unsigned long long) (sb->st_mtime < 0 ? 0 : sb->st_mtime),
	    (unsigned long long) (sb->st_atime < 0 ? 0 : sb->st_atime));
	if (verb) {
		fprintf(stderr, "File mtime %lld atime %lld\n",
		    (long long)sb->st_mtime, (long long)sb->st_atime);
		fprintf(stderr, "Sending file timestamps: %s", buf);
	}
	(void) atomicio(vwrite, fd, buf, strlen(buf));
	return (response());
}

void
toremote(char *targ, int argc, char **argv)
{
	char *bp, *host, *src, *suser, *thost, *tuser, *arg;
	arglist alist;
	int i;
	u_int j;

	memset(&alist, '\0', sizeof(alist));
	alist.list = NULL;

	*targ++ = 0;
	if (*targ == 0)
		targ = ".";

	arg = xstrdup(argv[argc - 1]);
	if ((thost = strrchr(arg, '@'))) {
		/* user@host */
		*thost++ = 0;
		tuser = arg;
		if (*tuser == '\0')
			tuser = NULL;
	} else {
		thost = arg;
		tuser = NULL;
	}

	if (tuser != NULL && !okname(tuser)) {
		free(arg);
		return;
	}

	for (i = 0; i < argc - 1; i++) {
		src = colon(argv[i]);
		if (src && throughlocal) {	/* extended remote to remote */
			*src++ = 0;
			if (*src == 0)
				src = ".";
			host = strrchr(argv[i], '@');
			if (host) {
				*host++ = 0;
				host = cleanhostname(host);
				suser = argv[i];
				if (*suser == '\0')
					suser = pwd->pw_name;
				else if (!okname(suser))
					continue;
			} else {
				host = cleanhostname(argv[i]);
				suser = NULL;
			}
			xasprintf(&bp, "%s -f %s%s", cmd,
			    *src == '-' ? "-- " : "", src);
			if (do_cmd(host, suser, bp, &remin, &remout) < 0)
				exit(1);
			free(bp);
			host = cleanhostname(thost);
			xasprintf(&bp, "%s -t %s%s", cmd,
			    *targ == '-' ? "-- " : "", targ);
			if (do_cmd2(host, tuser, bp, remin, remout) < 0)
				exit(1);
			free(bp);
			(void) close(remin);
			(void) close(remout);
			remin = remout = -1;
		} else if (src) {	/* standard remote to remote */
			freeargs(&alist);
			addargs(&alist, "%s", ssh_program);
			addargs(&alist, "-x");
			addargs(&alist, "-oClearAllForwardings=yes");
			addargs(&alist, "-n");
			for (j = 0; j < remote_remote_args.num; j++) {
				addargs(&alist, "%s",
				    remote_remote_args.list[j]);
			}
			*src++ = 0;
			if (*src == 0)
				src = ".";
			host = strrchr(argv[i], '@');

			if (host) {
				*host++ = 0;
				host = cleanhostname(host);
				suser = argv[i];
				if (*suser == '\0')
					suser = pwd->pw_name;
				else if (!okname(suser))
					continue;
				addargs(&alist, "-l");
				addargs(&alist, "%s", suser);
			} else {
				host = cleanhostname(argv[i]);
			}
			addargs(&alist, "--");
			addargs(&alist, "%s", host);
			addargs(&alist, "%s", cmd);
			addargs(&alist, "%s", src);
			addargs(&alist, "%s%s%s:%s",
			    tuser ? tuser : "", tuser ? "@" : "",
			    thost, targ);
			if (do_local_cmd(&alist) != 0)
				errs = 1;
		} else {	/* local to remote */
			if (remin == -1) {
				xasprintf(&bp, "%s -t %s%s", cmd,
				    *targ == '-' ? "-- " : "", targ);
				host = cleanhostname(thost);
				if (do_cmd(host, tuser, bp, &remin,
				    &remout) < 0)
					exit(1);
				if (response() < 0)
					exit(1);
				free(bp);
			}
			source(1, argv + i);
		}
	}
	free(arg);
}

void
tolocal(int argc, char **argv)
{
	char *bp, *host, *src, *suser;
	arglist alist;
	int i;

	memset(&alist, '\0', sizeof(alist));
	alist.list = NULL;

	for (i = 0; i < argc - 1; i++) {
		if (!(src = colon(argv[i]))) {	/* Local to local. */
			freeargs(&alist);
			addargs(&alist, "%s", _PATH_CP);
			if (iamrecursive)
				addargs(&alist, "-r");
			if (pflag)
				addargs(&alist, "-p");
			addargs(&alist, "--");
			addargs(&alist, "%s", argv[i]);
			addargs(&alist, "%s", argv[argc-1]);
			if (do_local_cmd(&alist))
				++errs;
			continue;
		}
		*src++ = 0;
		if (*src == 0)
			src = ".";
		if ((host = strrchr(argv[i], '@')) == NULL) {
			host = argv[i];
			suser = NULL;
		} else {
			*host++ = 0;
			suser = argv[i];
			if (*suser == '\0')
				suser = pwd->pw_name;
		}
		host = cleanhostname(host);
		xasprintf(&bp, "%s -f %s%s",
		    cmd, *src == '-' ? "-- " : "", src);
		if (do_cmd(host, suser, bp, &remin, &remout) < 0) {
			free(bp);
			++errs;
			continue;
		}
		free(bp);
		sink(1, argv + argc - 1);
		(void) close(remin);
		remin = remout = -1;
	}
}

void
source(int argc, char **argv)
{
	struct stat stb;
	static BUF buffer;
	BUF *bp;
	off_t i, statbytes;
	size_t amt, nr;
	int fd = -1, haderr, indx;
	char *last, *name, buf[2048], encname[PATH_MAX];
	int len;

	for (indx = 0; indx < argc; ++indx) {
		name = argv[indx];
		statbytes = 0;
		len = strlen(name);
		while (len > 1 && name[len-1] == '/')
			name[--len] = '\0';
		if ((fd = open(name, O_RDONLY|O_NONBLOCK, 0)) < 0)
			goto syserr;
		if (strchr(name, '\n') != NULL) {
			strnvis(encname, name, sizeof(encname), VIS_NL);
			name = encname;
		}
		if (fstat(fd, &stb) < 0) {
syserr:			run_err("%s: %s", name, strerror(errno));
			goto next;
		}
		if (stb.st_size < 0) {
			run_err("%s: %s", name, "Negative file size");
			goto next;
		}
		unset_nonblock(fd);
		switch (stb.st_mode & S_IFMT) {
		case S_IFREG:
			break;
		case S_IFDIR:
			if (iamrecursive) {
				rsource(name, &stb);
				goto next;
			}
			/* FALLTHROUGH */
		default:
			run_err("%s: not a regular file", name);
			goto next;
		}
		if ((last = strrchr(name, '/')) == NULL)
			last = name;
		else
			++last;
		curfile = last;
		if (pflag) {
			if (do_times(remout, verbose_mode, &stb) < 0)
				goto next;
		}
#define	FILEMODEMASK	(S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO)
		snprintf(buf, sizeof buf, "C%04o %lld %s\n",
		    (u_int) (stb.st_mode & FILEMODEMASK),
		    (long long)stb.st_size, last);
		if (verbose_mode)
			fmprintf(stderr, "Sending file modes: %s", buf);
		(void) atomicio(vwrite, remout, buf, strlen(buf));
		if (response() < 0)
			goto next;
		if ((bp = allocbuf(&buffer, fd, COPY_BUFLEN)) == NULL) {
next:			if (fd != -1) {
				(void) close(fd);
				fd = -1;
			}
			continue;
		}
		if (showprogress)
			start_progress_meter(curfile, stb.st_size, &statbytes);
		set_nonblock(remout);
		for (haderr = i = 0; i < stb.st_size; i += bp->cnt) {
			amt = bp->cnt;
			if (i + (off_t)amt > stb.st_size)
				amt = stb.st_size - i;
			if (!haderr) {
				if ((nr = atomicio(read, fd,
				    bp->buf, amt)) != amt) {
					haderr = errno;
					memset(bp->buf + nr, 0, amt - nr);
				}
			}
			/* Keep writing after error to retain sync */
			if (haderr) {
				(void)atomicio(vwrite, remout, bp->buf, amt);
				memset(bp->buf, 0, amt);
				continue;
			}
			if (atomicio6(vwrite, remout, bp->buf, amt, scpio,
			    &statbytes) != amt)
				haderr = errno;
		}
		unset_nonblock(remout);

		if (fd != -1) {
			if (close(fd) < 0 && !haderr)
				haderr = errno;
			fd = -1;
		}
		if (!haderr)
			(void) atomicio(vwrite, remout, "", 1);
		else
			run_err("%s: %s", name, strerror(haderr));
		(void) response();
		if (showprogress)
			stop_progress_meter();
	}
}

void
rsource(char *name, struct stat *statp)
{
	DIR *dirp;
	struct dirent *dp;
	char *last, *vect[1], path[PATH_MAX];

	if (!(dirp = opendir(name))) {
		run_err("%s: %s", name, strerror(errno));
		return;
	}
	last = strrchr(name, '/');
	if (last == NULL)
		last = name;
	else
		last++;
	if (pflag) {
		if (do_times(remout, verbose_mode, statp) < 0) {
			closedir(dirp);
			return;
		}
	}
	(void) snprintf(path, sizeof path, "D%04o %d %.1024s\n",
	    (u_int) (statp->st_mode & FILEMODEMASK), 0, last);
	if (verbose_mode)
		fmprintf(stderr, "Entering directory: %s", path);
	(void) atomicio(vwrite, remout, path, strlen(path));
	if (response() < 0) {
		closedir(dirp);
		return;
	}
	while ((dp = readdir(dirp)) != NULL) {
		if (dp->d_ino == 0)
			continue;
		if (!strcmp(dp->d_name, ".") || !strcmp(dp->d_name, ".."))
			continue;
		if (strlen(name) + 1 + strlen(dp->d_name) >= sizeof(path) - 1) {
			run_err("%s/%s: name too long", name, dp->d_name);
			continue;
		}
		(void) snprintf(path, sizeof path, "%s/%s", name, dp->d_name);
		vect[0] = path;
		source(1, vect);
	}
	(void) closedir(dirp);
	(void) atomicio(vwrite, remout, "E\n", 2);
	(void) response();
}

#define TYPE_OVERFLOW(type, val) \
	((sizeof(type) == 4 && (val) > INT32_MAX) || \
	 (sizeof(type) == 8 && (val) > INT64_MAX) || \
	 (sizeof(type) != 4 && sizeof(type) != 8))

void
sink(int argc, char **argv)
{
	static BUF buffer;
	struct stat stb;
	enum {
		YES, NO, DISPLAYED
	} wrerr;
	BUF *bp;
	off_t i;
	size_t j, count;
	int amt, exists, first, ofd;
	mode_t mode, omode, mask;
	off_t size, statbytes;
	unsigned long long ull;
	int setimes, targisdir, wrerrno = 0;
	char ch, *cp, *np, *targ, *why, *vect[1], buf[2048], visbuf[2048];
	struct timeval tv[2];

#define	atime	tv[0]
#define	mtime	tv[1]
#define	SCREWUP(str)	{ why = str; goto screwup; }

	if (TYPE_OVERFLOW(time_t, 0) || TYPE_OVERFLOW(off_t, 0))
		SCREWUP("Unexpected off_t/time_t size");

	setimes = targisdir = 0;
	mask = umask(0);
	if (!pflag)
		(void) umask(mask);
	if (argc != 1) {
		run_err("ambiguous target");
		exit(1);
	}
	targ = *argv;
	if (targetshouldbedirectory)
		verifydir(targ);

	(void) atomicio(vwrite, remout, "", 1);
	if (stat(targ, &stb) == 0 && S_ISDIR(stb.st_mode))
		targisdir = 1;
	for (first = 1;; first = 0) {
		cp = buf;
		if (atomicio(read, remin, cp, 1) != 1)
			return;
		if (*cp++ == '\n')
			SCREWUP("unexpected <newline>");
		do {
			if (atomicio(read, remin, &ch, sizeof(ch)) != sizeof(ch))
				SCREWUP("lost connection");
			*cp++ = ch;
		} while (cp < &buf[sizeof(buf) - 1] && ch != '\n');
		*cp = 0;
		if (verbose_mode)
			fmprintf(stderr, "Sink: %s", buf);

		if (buf[0] == '\01' || buf[0] == '\02') {
			if (iamremote == 0) {
				(void) snmprintf(visbuf, sizeof(visbuf),
				    NULL, "%s", buf + 1);
				(void) atomicio(vwrite, STDERR_FILENO,
				    visbuf, strlen(visbuf));
			}
			if (buf[0] == '\02')
				exit(1);
			++errs;
			continue;
		}
		if (buf[0] == 'E') {
			(void) atomicio(vwrite, remout, "", 1);
			return;
		}
		if (ch == '\n')
			*--cp = 0;

		cp = buf;
		if (*cp == 'T') {
			setimes++;
			cp++;
			if (!isdigit((unsigned char)*cp))
				SCREWUP("mtime.sec not present");
			ull = strtoull(cp, &cp, 10);
			if (!cp || *cp++ != ' ')
				SCREWUP("mtime.sec not delimited");
			if (TYPE_OVERFLOW(time_t, ull))
				setimes = 0;	/* out of range */
			mtime.tv_sec = ull;
			mtime.tv_usec = strtol(cp, &cp, 10);
			if (!cp || *cp++ != ' ' || mtime.tv_usec < 0 ||
			    mtime.tv_usec > 999999)
				SCREWUP("mtime.usec not delimited");
			if (!isdigit((unsigned char)*cp))
				SCREWUP("atime.sec not present");
			ull = strtoull(cp, &cp, 10);
			if (!cp || *cp++ != ' ')
				SCREWUP("atime.sec not delimited");
			if (TYPE_OVERFLOW(time_t, ull))
				setimes = 0;	/* out of range */
			atime.tv_sec = ull;
			atime.tv_usec = strtol(cp, &cp, 10);
			if (!cp || *cp++ != '\0' || atime.tv_usec < 0 ||
			    atime.tv_usec > 999999)
				SCREWUP("atime.usec not delimited");
			(void) atomicio(vwrite, remout, "", 1);
			continue;
		}
		if (*cp != 'C' && *cp != 'D') {
			/*
			 * Check for the case "rcp remote:foo\* local:bar".
			 * In this case, the line "No match." can be returned
			 * by the shell before the rcp command on the remote is
			 * executed so the ^Aerror_message convention isn't
			 * followed.
			 */
			if (first) {
				run_err("%s", cp);
				exit(1);
			}
			SCREWUP("expected control record");
		}
		mode = 0;
		for (++cp; cp < buf + 5; cp++) {
			if (*cp < '0' || *cp > '7')
				SCREWUP("bad mode");
			mode = (mode << 3) | (*cp - '0');
		}
		if (*cp++ != ' ')
			SCREWUP("mode not delimited");

		if (!isdigit((unsigned char)*cp))
			SCREWUP("size not present");
		ull = strtoull(cp, &cp, 10);
		if (!cp || *cp++ != ' ')
			SCREWUP("size not delimited");
		if (TYPE_OVERFLOW(off_t, ull))
			SCREWUP("size out of range");
		size = (off_t)ull;

		if ((strchr(cp, '/') != NULL) || (strcmp(cp, "..") == 0)) {
			run_err("error: unexpected filename: %s", cp);
			exit(1);
		}
		if (targisdir) {
			static char *namebuf;
			static size_t cursize;
			size_t need;

			need = strlen(targ) + strlen(cp) + 250;
			if (need > cursize) {
				free(namebuf);
				namebuf = xmalloc(need);
				cursize = need;
			}
			(void) snprintf(namebuf, need, "%s%s%s", targ,
			    strcmp(targ, "/") ? "/" : "", cp);
			np = namebuf;
		} else
			np = targ;
		curfile = cp;
		exists = stat(np, &stb) == 0;
		if (buf[0] == 'D') {
			int mod_flag = pflag;
			if (!iamrecursive)
				SCREWUP("received directory without -r");
			if (exists) {
				if (!S_ISDIR(stb.st_mode)) {
					errno = ENOTDIR;
					goto bad;
				}
				if (pflag)
					(void) chmod(np, mode);
			} else {
				/* Handle copying from a read-only
				   directory */
				mod_flag = 1;
				if (mkdir(np, mode | S_IRWXU) < 0)
					goto bad;
			}
			vect[0] = xstrdup(np);
			sink(1, vect);
			if (setimes) {
				setimes = 0;
				if (utimes(vect[0], tv) < 0)
					run_err("%s: set times: %s",
					    vect[0], strerror(errno));
			}
			if (mod_flag)
				(void) chmod(vect[0], mode);
			free(vect[0]);
			continue;
		}
		omode = mode;
		mode |= S_IWUSR;
		if ((ofd = open(np, O_WRONLY|O_CREAT, mode)) < 0) {
bad:			run_err("%s: %s", np, strerror(errno));
			continue;
		}
		(void) atomicio(vwrite, remout, "", 1);
		if ((bp = allocbuf(&buffer, ofd, COPY_BUFLEN)) == NULL) {
			(void) close(ofd);
			continue;
		}
		cp = bp->buf;
		wrerr = NO;

		statbytes = 0;
		if (showprogress)
			start_progress_meter(curfile, size, &statbytes);
		set_nonblock(remin);
		for (count = i = 0; i < size; i += bp->cnt) {
			amt = bp->cnt;
			if (i + amt > size)
				amt = size - i;
			count += amt;
			do {
				j = atomicio6(read, remin, cp, amt,
				    scpio, &statbytes);
				if (j == 0) {
					run_err("%s", j != EPIPE ?
					    strerror(errno) :
					    "dropped connection");
					exit(1);
				}
				amt -= j;
				cp += j;
			} while (amt > 0);

			if (count == bp->cnt) {
				/* Keep reading so we stay sync'd up. */
				if (wrerr == NO) {
					if (atomicio(vwrite, ofd, bp->buf,
					    count) != count) {
						wrerr = YES;
						wrerrno = errno;
					}
				}
				count = 0;
				cp = bp->buf;
			}
		}
		unset_nonblock(remin);
		if (count != 0 && wrerr == NO &&
		    atomicio(vwrite, ofd, bp->buf, count) != count) {
			wrerr = YES;
			wrerrno = errno;
		}
		if (wrerr == NO && (!exists || S_ISREG(stb.st_mode)) &&
		    ftruncate(ofd, size) != 0) {
			run_err("%s: truncate: %s", np, strerror(errno));
			wrerr = DISPLAYED;
		}
		if (pflag) {
			if (exists || omode != mode)
				if (fchmod(ofd, omode)) {
					run_err("%s: set mode: %s",
					    np, strerror(errno));
					wrerr = DISPLAYED;
				}
		} else {
			if (!exists && omode != mode)
				if (fchmod(ofd, omode & ~mask)) {
					run_err("%s: set mode: %s",
					    np, strerror(errno));
					wrerr = DISPLAYED;
				}
		}
		if (close(ofd) == -1) {
			wrerr = YES;
			wrerrno = errno;
		}
		(void) response();
		if (showprogress)
			stop_progress_meter();
		if (setimes && wrerr == NO) {
			setimes = 0;
			if (utimes(np, tv) < 0) {
				run_err("%s: set times: %s",
				    np, strerror(errno));
				wrerr = DISPLAYED;
			}
		}
		switch (wrerr) {
		case YES:
			run_err("%s: %s", np, strerror(wrerrno));
			break;
		case NO:
			(void) atomicio(vwrite, remout, "", 1);
			break;
		case DISPLAYED:
			break;
		}
	}
screwup:
	run_err("protocol error: %s", why);
	exit(1);
}

int
response(void)
{
	char ch, *cp, resp, rbuf[2048], visbuf[2048];

	if (atomicio(read, remin, &resp, sizeof(resp)) != sizeof(resp))
		lostconn(0);

	cp = rbuf;
	switch (resp) {
	case 0:		/* ok */
		return (0);
	default:
		*cp++ = resp;
		/* FALLTHROUGH */
	case 1:		/* error, followed by error msg */
	case 2:		/* fatal error, "" */
		do {
			if (atomicio(read, remin, &ch, sizeof(ch)) != sizeof(ch))
				lostconn(0);
			*cp++ = ch;
		} while (cp < &rbuf[sizeof(rbuf) - 1] && ch != '\n');

		if (!iamremote) {
			cp[-1] = '\0';
			(void) snmprintf(visbuf, sizeof(visbuf),
			    NULL, "%s\n", rbuf);
			(void) atomicio(vwrite, STDERR_FILENO,
			    visbuf, strlen(visbuf));
		}
		++errs;
		if (resp == 1)
			return (-1);
		exit(1);
	}
	/* NOTREACHED */
}

void
usage(void)
{
	(void) fprintf(stderr,
	    "usage: scp [-346BCpqrv] [-c cipher] [-F ssh_config] [-i identity_file]\n"
	    "           [-l limit] [-o ssh_option] [-P port] [-S program]\n"
	    "           [[user@]host1:]file1 ... [[user@]host2:]file2\n");
	exit(1);
}

void
run_err(const char *fmt,...)
{
	static FILE *fp;
	va_list ap;

	++errs;
	if (fp != NULL || (remout != -1 && (fp = fdopen(remout, "w")))) {
		(void) fprintf(fp, "%c", 0x01);
		(void) fprintf(fp, "scp: ");
		va_start(ap, fmt);
		(void) vfprintf(fp, fmt, ap);
		va_end(ap);
		(void) fprintf(fp, "\n");
		(void) fflush(fp);
	}

	if (!iamremote) {
		va_start(ap, fmt);
		vfmprintf(stderr, fmt, ap);
		va_end(ap);
		fprintf(stderr, "\n");
	}
}

void
verifydir(char *cp)
{
	struct stat stb;

	if (!stat(cp, &stb)) {
		if (S_ISDIR(stb.st_mode))
			return;
		errno = ENOTDIR;
	}
	run_err("%s: %s", cp, strerror(errno));
	killchild(0);
}

int
okname(char *cp0)
{
	int c;
	char *cp;

	cp = cp0;
	do {
		c = (int)*cp;
		if (c & 0200)
			goto bad;
		if (!isalpha(c) && !isdigit((unsigned char)c)) {
			switch (c) {
			case '\'':
			case '"':
			case '`':
			case ' ':
			case '#':
				goto bad;
			default:
				break;
			}
		}
	} while (*++cp);
	return (1);

bad:	fmprintf(stderr, "%s: invalid user name\n", cp0);
	return (0);
}

BUF *
allocbuf(BUF *bp, int fd, int blksize)
{
	size_t size;
	struct stat stb;

	if (fstat(fd, &stb) < 0) {
		run_err("fstat: %s", strerror(errno));
		return (0);
	}
	size = ROUNDUP(stb.st_blksize, blksize);
	if (size == 0)
		size = blksize;
	if (bp->cnt >= size)
		return (bp);
	bp->buf = xrecallocarray(bp->buf, bp->cnt, size, 1);
	bp->cnt = size;
	return (bp);
}

void
lostconn(int signo)
{
	if (!iamremote)
		(void)write(STDERR_FILENO, "lost connection\n", 16);
	if (signo)
		_exit(1);
	else
		exit(1);
}