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      1 /* $OpenBSD: scp.c,v 1.182 2015/04/24 01:36:00 deraadt Exp $ */
      2 /*
      3  * scp - secure remote copy.  This is basically patched BSD rcp which
      4  * uses ssh to do the data transfer (instead of using rcmd).
      5  *
      6  * NOTE: This version should NOT be suid root.  (This uses ssh to
      7  * do the transfer and ssh has the necessary privileges.)
      8  *
      9  * 1995 Timo Rinne <tri (at) iki.fi>, Tatu Ylonen <ylo (at) cs.hut.fi>
     10  *
     11  * As far as I am concerned, the code I have written for this software
     12  * can be used freely for any purpose.  Any derived versions of this
     13  * software must be clearly marked as such, and if the derived work is
     14  * incompatible with the protocol description in the RFC file, it must be
     15  * called by a name other than "ssh" or "Secure Shell".
     16  */
     17 /*
     18  * Copyright (c) 1999 Theo de Raadt.  All rights reserved.
     19  * Copyright (c) 1999 Aaron Campbell.  All rights reserved.
     20  *
     21  * Redistribution and use in source and binary forms, with or without
     22  * modification, are permitted provided that the following conditions
     23  * are met:
     24  * 1. Redistributions of source code must retain the above copyright
     25  *    notice, this list of conditions and the following disclaimer.
     26  * 2. Redistributions in binary form must reproduce the above copyright
     27  *    notice, this list of conditions and the following disclaimer in the
     28  *    documentation and/or other materials provided with the distribution.
     29  *
     30  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     31  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     32  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     33  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     34  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     35  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     36  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     37  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     38  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     39  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     40  */
     41 
     42 /*
     43  * Parts from:
     44  *
     45  * Copyright (c) 1983, 1990, 1992, 1993, 1995
     46  *	The Regents of the University of California.  All rights reserved.
     47  *
     48  * Redistribution and use in source and binary forms, with or without
     49  * modification, are permitted provided that the following conditions
     50  * are met:
     51  * 1. Redistributions of source code must retain the above copyright
     52  *    notice, this list of conditions and the following disclaimer.
     53  * 2. Redistributions in binary form must reproduce the above copyright
     54  *    notice, this list of conditions and the following disclaimer in the
     55  *    documentation and/or other materials provided with the distribution.
     56  * 3. Neither the name of the University nor the names of its contributors
     57  *    may be used to endorse or promote products derived from this software
     58  *    without specific prior written permission.
     59  *
     60  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     61  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     62  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     63  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     64  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     65  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     66  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     67  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     68  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     69  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     70  * SUCH DAMAGE.
     71  *
     72  */
     73 
     74 #include "includes.h"
     75 
     76 #include <sys/types.h>
     77 #include <sys/param.h>
     78 #ifdef HAVE_SYS_STAT_H
     79 # include <sys/stat.h>
     80 #endif
     81 #ifdef HAVE_POLL_H
     82 #include <poll.h>
     83 #else
     84 # ifdef HAVE_SYS_POLL_H
     85 #  include <sys/poll.h>
     86 # endif
     87 #endif
     88 #ifdef HAVE_SYS_TIME_H
     89 # include <sys/time.h>
     90 #endif
     91 #include <sys/wait.h>
     92 #include <sys/uio.h>
     93 
     94 #include <ctype.h>
     95 #include <dirent.h>
     96 #include <errno.h>
     97 #include <fcntl.h>
     98 #include <limits.h>
     99 #include <pwd.h>
    100 #include <signal.h>
    101 #include <stdarg.h>
    102 #include <stdio.h>
    103 #include <stdlib.h>
    104 #include <string.h>
    105 #include <time.h>
    106 #include <unistd.h>
    107 #if defined(HAVE_STRNVIS) && defined(HAVE_VIS_H) && !defined(BROKEN_STRNVIS)
    108 #include <vis.h>
    109 #endif
    110 
    111 #include "xmalloc.h"
    112 #include "atomicio.h"
    113 #include "pathnames.h"
    114 #include "log.h"
    115 #include "misc.h"
    116 #include "progressmeter.h"
    117 
    118 extern char *__progname;
    119 
    120 #define COPY_BUFLEN	16384
    121 
    122 int do_cmd(char *host, char *remuser, char *cmd, int *fdin, int *fdout);
    123 int do_cmd2(char *host, char *remuser, char *cmd, int fdin, int fdout);
    124 
    125 /* Struct for addargs */
    126 arglist args;
    127 arglist remote_remote_args;
    128 
    129 /* Bandwidth limit */
    130 long long limit_kbps = 0;
    131 struct bwlimit bwlimit;
    132 
    133 /* Name of current file being transferred. */
    134 char *curfile;
    135 
    136 /* This is set to non-zero to enable verbose mode. */
    137 int verbose_mode = 0;
    138 
    139 /* This is set to zero if the progressmeter is not desired. */
    140 int showprogress = 1;
    141 
    142 /*
    143  * This is set to non-zero if remote-remote copy should be piped
    144  * through this process.
    145  */
    146 int throughlocal = 0;
    147 
    148 /* This is the program to execute for the secured connection. ("ssh" or -S) */
    149 char *ssh_program = _PATH_SSH_PROGRAM;
    150 
    151 /* This is used to store the pid of ssh_program */
    152 pid_t do_cmd_pid = -1;
    153 
    154 static void
    155 killchild(int signo)
    156 {
    157 	if (do_cmd_pid > 1) {
    158 		kill(do_cmd_pid, signo ? signo : SIGTERM);
    159 		waitpid(do_cmd_pid, NULL, 0);
    160 	}
    161 
    162 	if (signo)
    163 		_exit(1);
    164 	exit(1);
    165 }
    166 
    167 static void
    168 suspchild(int signo)
    169 {
    170 	int status;
    171 
    172 	if (do_cmd_pid > 1) {
    173 		kill(do_cmd_pid, signo);
    174 		while (waitpid(do_cmd_pid, &status, WUNTRACED) == -1 &&
    175 		    errno == EINTR)
    176 			;
    177 		kill(getpid(), SIGSTOP);
    178 	}
    179 }
    180 
    181 static int
    182 do_local_cmd(arglist *a)
    183 {
    184 	u_int i;
    185 	int status;
    186 	pid_t pid;
    187 
    188 	if (a->num == 0)
    189 		fatal("do_local_cmd: no arguments");
    190 
    191 	if (verbose_mode) {
    192 		fprintf(stderr, "Executing:");
    193 		for (i = 0; i < a->num; i++)
    194 			fprintf(stderr, " %s", a->list[i]);
    195 		fprintf(stderr, "\n");
    196 	}
    197 	if ((pid = fork()) == -1)
    198 		fatal("do_local_cmd: fork: %s", strerror(errno));
    199 
    200 	if (pid == 0) {
    201 		execvp(a->list[0], a->list);
    202 		perror(a->list[0]);
    203 		exit(1);
    204 	}
    205 
    206 	do_cmd_pid = pid;
    207 	signal(SIGTERM, killchild);
    208 	signal(SIGINT, killchild);
    209 	signal(SIGHUP, killchild);
    210 
    211 	while (waitpid(pid, &status, 0) == -1)
    212 		if (errno != EINTR)
    213 			fatal("do_local_cmd: waitpid: %s", strerror(errno));
    214 
    215 	do_cmd_pid = -1;
    216 
    217 	if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
    218 		return (-1);
    219 
    220 	return (0);
    221 }
    222 
    223 /*
    224  * This function executes the given command as the specified user on the
    225  * given host.  This returns < 0 if execution fails, and >= 0 otherwise. This
    226  * assigns the input and output file descriptors on success.
    227  */
    228 
    229 int
    230 do_cmd(char *host, char *remuser, char *cmd, int *fdin, int *fdout)
    231 {
    232 	int pin[2], pout[2], reserved[2];
    233 
    234 	if (verbose_mode)
    235 		fprintf(stderr,
    236 		    "Executing: program %s host %s, user %s, command %s\n",
    237 		    ssh_program, host,
    238 		    remuser ? remuser : "(unspecified)", cmd);
    239 
    240 	/*
    241 	 * Reserve two descriptors so that the real pipes won't get
    242 	 * descriptors 0 and 1 because that will screw up dup2 below.
    243 	 */
    244 	if (pipe(reserved) < 0)
    245 		fatal("pipe: %s", strerror(errno));
    246 
    247 	/* Create a socket pair for communicating with ssh. */
    248 	if (pipe(pin) < 0)
    249 		fatal("pipe: %s", strerror(errno));
    250 	if (pipe(pout) < 0)
    251 		fatal("pipe: %s", strerror(errno));
    252 
    253 	/* Free the reserved descriptors. */
    254 	close(reserved[0]);
    255 	close(reserved[1]);
    256 
    257 	signal(SIGTSTP, suspchild);
    258 	signal(SIGTTIN, suspchild);
    259 	signal(SIGTTOU, suspchild);
    260 
    261 	/* Fork a child to execute the command on the remote host using ssh. */
    262 	do_cmd_pid = fork();
    263 	if (do_cmd_pid == 0) {
    264 		/* Child. */
    265 		close(pin[1]);
    266 		close(pout[0]);
    267 		dup2(pin[0], 0);
    268 		dup2(pout[1], 1);
    269 		close(pin[0]);
    270 		close(pout[1]);
    271 
    272 		replacearg(&args, 0, "%s", ssh_program);
    273 		if (remuser != NULL) {
    274 			addargs(&args, "-l");
    275 			addargs(&args, "%s", remuser);
    276 		}
    277 		addargs(&args, "--");
    278 		addargs(&args, "%s", host);
    279 		addargs(&args, "%s", cmd);
    280 
    281 		execvp(ssh_program, args.list);
    282 		perror(ssh_program);
    283 		exit(1);
    284 	} else if (do_cmd_pid == -1) {
    285 		fatal("fork: %s", strerror(errno));
    286 	}
    287 	/* Parent.  Close the other side, and return the local side. */
    288 	close(pin[0]);
    289 	*fdout = pin[1];
    290 	close(pout[1]);
    291 	*fdin = pout[0];
    292 	signal(SIGTERM, killchild);
    293 	signal(SIGINT, killchild);
    294 	signal(SIGHUP, killchild);
    295 	return 0;
    296 }
    297 
    298 /*
    299  * This functions executes a command simlar to do_cmd(), but expects the
    300  * input and output descriptors to be setup by a previous call to do_cmd().
    301  * This way the input and output of two commands can be connected.
    302  */
    303 int
    304 do_cmd2(char *host, char *remuser, char *cmd, int fdin, int fdout)
    305 {
    306 	pid_t pid;
    307 	int status;
    308 
    309 	if (verbose_mode)
    310 		fprintf(stderr,
    311 		    "Executing: 2nd program %s host %s, user %s, command %s\n",
    312 		    ssh_program, host,
    313 		    remuser ? remuser : "(unspecified)", cmd);
    314 
    315 	/* Fork a child to execute the command on the remote host using ssh. */
    316 	pid = fork();
    317 	if (pid == 0) {
    318 		dup2(fdin, 0);
    319 		dup2(fdout, 1);
    320 
    321 		replacearg(&args, 0, "%s", ssh_program);
    322 		if (remuser != NULL) {
    323 			addargs(&args, "-l");
    324 			addargs(&args, "%s", remuser);
    325 		}
    326 		addargs(&args, "--");
    327 		addargs(&args, "%s", host);
    328 		addargs(&args, "%s", cmd);
    329 
    330 		execvp(ssh_program, args.list);
    331 		perror(ssh_program);
    332 		exit(1);
    333 	} else if (pid == -1) {
    334 		fatal("fork: %s", strerror(errno));
    335 	}
    336 	while (waitpid(pid, &status, 0) == -1)
    337 		if (errno != EINTR)
    338 			fatal("do_cmd2: waitpid: %s", strerror(errno));
    339 	return 0;
    340 }
    341 
    342 typedef struct {
    343 	size_t cnt;
    344 	char *buf;
    345 } BUF;
    346 
    347 BUF *allocbuf(BUF *, int, int);
    348 void lostconn(int);
    349 int okname(char *);
    350 void run_err(const char *,...);
    351 void verifydir(char *);
    352 
    353 struct passwd *pwd;
    354 uid_t userid;
    355 int errs, remin, remout;
    356 int pflag, iamremote, iamrecursive, targetshouldbedirectory;
    357 
    358 #define	CMDNEEDS	64
    359 char cmd[CMDNEEDS];		/* must hold "rcp -r -p -d\0" */
    360 
    361 int response(void);
    362 void rsource(char *, struct stat *);
    363 void sink(int, char *[]);
    364 void source(int, char *[]);
    365 void tolocal(int, char *[]);
    366 void toremote(char *, int, char *[]);
    367 void usage(void);
    368 
    369 int
    370 main(int argc, char **argv)
    371 {
    372 	int ch, fflag, tflag, status, n;
    373 	char *targ, **newargv;
    374 	const char *errstr;
    375 	extern char *optarg;
    376 	extern int optind;
    377 
    378 	/* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
    379 	sanitise_stdfd();
    380 
    381 	/* Copy argv, because we modify it */
    382 	newargv = xcalloc(MAX(argc + 1, 1), sizeof(*newargv));
    383 	for (n = 0; n < argc; n++)
    384 		newargv[n] = xstrdup(argv[n]);
    385 	argv = newargv;
    386 
    387 	__progname = ssh_get_progname(argv[0]);
    388 
    389 	memset(&args, '\0', sizeof(args));
    390 	memset(&remote_remote_args, '\0', sizeof(remote_remote_args));
    391 	args.list = remote_remote_args.list = NULL;
    392 	addargs(&args, "%s", ssh_program);
    393 	addargs(&args, "-x");
    394 	addargs(&args, "-oForwardAgent=no");
    395 	addargs(&args, "-oPermitLocalCommand=no");
    396 	addargs(&args, "-oClearAllForwardings=yes");
    397 
    398 	fflag = tflag = 0;
    399 	while ((ch = getopt(argc, argv, "dfl:prtvBCc:i:P:q12346S:o:F:")) != -1)
    400 		switch (ch) {
    401 		/* User-visible flags. */
    402 		case '1':
    403 		case '2':
    404 		case '4':
    405 		case '6':
    406 		case 'C':
    407 			addargs(&args, "-%c", ch);
    408 			addargs(&remote_remote_args, "-%c", ch);
    409 			break;
    410 		case '3':
    411 			throughlocal = 1;
    412 			break;
    413 		case 'o':
    414 		case 'c':
    415 		case 'i':
    416 		case 'F':
    417 			addargs(&remote_remote_args, "-%c", ch);
    418 			addargs(&remote_remote_args, "%s", optarg);
    419 			addargs(&args, "-%c", ch);
    420 			addargs(&args, "%s", optarg);
    421 			break;
    422 		case 'P':
    423 			addargs(&remote_remote_args, "-p");
    424 			addargs(&remote_remote_args, "%s", optarg);
    425 			addargs(&args, "-p");
    426 			addargs(&args, "%s", optarg);
    427 			break;
    428 		case 'B':
    429 			addargs(&remote_remote_args, "-oBatchmode=yes");
    430 			addargs(&args, "-oBatchmode=yes");
    431 			break;
    432 		case 'l':
    433 			limit_kbps = strtonum(optarg, 1, 100 * 1024 * 1024,
    434 			    &errstr);
    435 			if (errstr != NULL)
    436 				usage();
    437 			limit_kbps *= 1024; /* kbps */
    438 			bandwidth_limit_init(&bwlimit, limit_kbps, COPY_BUFLEN);
    439 			break;
    440 		case 'p':
    441 			pflag = 1;
    442 			break;
    443 		case 'r':
    444 			iamrecursive = 1;
    445 			break;
    446 		case 'S':
    447 			ssh_program = xstrdup(optarg);
    448 			break;
    449 		case 'v':
    450 			addargs(&args, "-v");
    451 			addargs(&remote_remote_args, "-v");
    452 			verbose_mode = 1;
    453 			break;
    454 		case 'q':
    455 			addargs(&args, "-q");
    456 			addargs(&remote_remote_args, "-q");
    457 			showprogress = 0;
    458 			break;
    459 
    460 		/* Server options. */
    461 		case 'd':
    462 			targetshouldbedirectory = 1;
    463 			break;
    464 		case 'f':	/* "from" */
    465 			iamremote = 1;
    466 			fflag = 1;
    467 			break;
    468 		case 't':	/* "to" */
    469 			iamremote = 1;
    470 			tflag = 1;
    471 #ifdef HAVE_CYGWIN
    472 			setmode(0, O_BINARY);
    473 #endif
    474 			break;
    475 		default:
    476 			usage();
    477 		}
    478 	argc -= optind;
    479 	argv += optind;
    480 
    481 	if ((pwd = getpwuid(userid = getuid())) == NULL)
    482 		fatal("unknown user %u", (u_int) userid);
    483 
    484 	if (!isatty(STDOUT_FILENO))
    485 		showprogress = 0;
    486 
    487 	remin = STDIN_FILENO;
    488 	remout = STDOUT_FILENO;
    489 
    490 	if (fflag) {
    491 		/* Follow "protocol", send data. */
    492 		(void) response();
    493 		source(argc, argv);
    494 		exit(errs != 0);
    495 	}
    496 	if (tflag) {
    497 		/* Receive data. */
    498 		sink(argc, argv);
    499 		exit(errs != 0);
    500 	}
    501 	if (argc < 2)
    502 		usage();
    503 	if (argc > 2)
    504 		targetshouldbedirectory = 1;
    505 
    506 	remin = remout = -1;
    507 	do_cmd_pid = -1;
    508 	/* Command to be executed on remote system using "ssh". */
    509 	(void) snprintf(cmd, sizeof cmd, "scp%s%s%s%s",
    510 	    verbose_mode ? " -v" : "",
    511 	    iamrecursive ? " -r" : "", pflag ? " -p" : "",
    512 	    targetshouldbedirectory ? " -d" : "");
    513 
    514 	(void) signal(SIGPIPE, lostconn);
    515 
    516 	if ((targ = colon(argv[argc - 1])))	/* Dest is remote host. */
    517 		toremote(targ, argc, argv);
    518 	else {
    519 		if (targetshouldbedirectory)
    520 			verifydir(argv[argc - 1]);
    521 		tolocal(argc, argv);	/* Dest is local host. */
    522 	}
    523 	/*
    524 	 * Finally check the exit status of the ssh process, if one was forked
    525 	 * and no error has occurred yet
    526 	 */
    527 	if (do_cmd_pid != -1 && errs == 0) {
    528 		if (remin != -1)
    529 		    (void) close(remin);
    530 		if (remout != -1)
    531 		    (void) close(remout);
    532 		if (waitpid(do_cmd_pid, &status, 0) == -1)
    533 			errs = 1;
    534 		else {
    535 			if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
    536 				errs = 1;
    537 		}
    538 	}
    539 	exit(errs != 0);
    540 }
    541 
    542 /* Callback from atomicio6 to update progress meter and limit bandwidth */
    543 static int
    544 scpio(void *_cnt, size_t s)
    545 {
    546 	off_t *cnt = (off_t *)_cnt;
    547 
    548 	*cnt += s;
    549 	if (limit_kbps > 0)
    550 		bandwidth_limit(&bwlimit, s);
    551 	return 0;
    552 }
    553 
    554 static int
    555 do_times(int fd, int verb, const struct stat *sb)
    556 {
    557 	/* strlen(2^64) == 20; strlen(10^6) == 7 */
    558 	char buf[(20 + 7 + 2) * 2 + 2];
    559 
    560 	(void)snprintf(buf, sizeof(buf), "T%llu 0 %llu 0\n",
    561 	    (unsigned long long) (sb->st_mtime < 0 ? 0 : sb->st_mtime),
    562 	    (unsigned long long) (sb->st_atime < 0 ? 0 : sb->st_atime));
    563 	if (verb) {
    564 		fprintf(stderr, "File mtime %lld atime %lld\n",
    565 		    (long long)sb->st_mtime, (long long)sb->st_atime);
    566 		fprintf(stderr, "Sending file timestamps: %s", buf);
    567 	}
    568 	(void) atomicio(vwrite, fd, buf, strlen(buf));
    569 	return (response());
    570 }
    571 
    572 void
    573 toremote(char *targ, int argc, char **argv)
    574 {
    575 	char *bp, *host, *src, *suser, *thost, *tuser, *arg;
    576 	arglist alist;
    577 	int i;
    578 	u_int j;
    579 
    580 	memset(&alist, '\0', sizeof(alist));
    581 	alist.list = NULL;
    582 
    583 	*targ++ = 0;
    584 	if (*targ == 0)
    585 		targ = ".";
    586 
    587 	arg = xstrdup(argv[argc - 1]);
    588 	if ((thost = strrchr(arg, '@'))) {
    589 		/* user@host */
    590 		*thost++ = 0;
    591 		tuser = arg;
    592 		if (*tuser == '\0')
    593 			tuser = NULL;
    594 	} else {
    595 		thost = arg;
    596 		tuser = NULL;
    597 	}
    598 
    599 	if (tuser != NULL && !okname(tuser)) {
    600 		free(arg);
    601 		return;
    602 	}
    603 
    604 	for (i = 0; i < argc - 1; i++) {
    605 		src = colon(argv[i]);
    606 		if (src && throughlocal) {	/* extended remote to remote */
    607 			*src++ = 0;
    608 			if (*src == 0)
    609 				src = ".";
    610 			host = strrchr(argv[i], '@');
    611 			if (host) {
    612 				*host++ = 0;
    613 				host = cleanhostname(host);
    614 				suser = argv[i];
    615 				if (*suser == '\0')
    616 					suser = pwd->pw_name;
    617 				else if (!okname(suser))
    618 					continue;
    619 			} else {
    620 				host = cleanhostname(argv[i]);
    621 				suser = NULL;
    622 			}
    623 			xasprintf(&bp, "%s -f %s%s", cmd,
    624 			    *src == '-' ? "-- " : "", src);
    625 			if (do_cmd(host, suser, bp, &remin, &remout) < 0)
    626 				exit(1);
    627 			free(bp);
    628 			host = cleanhostname(thost);
    629 			xasprintf(&bp, "%s -t %s%s", cmd,
    630 			    *targ == '-' ? "-- " : "", targ);
    631 			if (do_cmd2(host, tuser, bp, remin, remout) < 0)
    632 				exit(1);
    633 			free(bp);
    634 			(void) close(remin);
    635 			(void) close(remout);
    636 			remin = remout = -1;
    637 		} else if (src) {	/* standard remote to remote */
    638 			freeargs(&alist);
    639 			addargs(&alist, "%s", ssh_program);
    640 			addargs(&alist, "-x");
    641 			addargs(&alist, "-oClearAllForwardings=yes");
    642 			addargs(&alist, "-n");
    643 			for (j = 0; j < remote_remote_args.num; j++) {
    644 				addargs(&alist, "%s",
    645 				    remote_remote_args.list[j]);
    646 			}
    647 			*src++ = 0;
    648 			if (*src == 0)
    649 				src = ".";
    650 			host = strrchr(argv[i], '@');
    651 
    652 			if (host) {
    653 				*host++ = 0;
    654 				host = cleanhostname(host);
    655 				suser = argv[i];
    656 				if (*suser == '\0')
    657 					suser = pwd->pw_name;
    658 				else if (!okname(suser))
    659 					continue;
    660 				addargs(&alist, "-l");
    661 				addargs(&alist, "%s", suser);
    662 			} else {
    663 				host = cleanhostname(argv[i]);
    664 			}
    665 			addargs(&alist, "--");
    666 			addargs(&alist, "%s", host);
    667 			addargs(&alist, "%s", cmd);
    668 			addargs(&alist, "%s", src);
    669 			addargs(&alist, "%s%s%s:%s",
    670 			    tuser ? tuser : "", tuser ? "@" : "",
    671 			    thost, targ);
    672 			if (do_local_cmd(&alist) != 0)
    673 				errs = 1;
    674 		} else {	/* local to remote */
    675 			if (remin == -1) {
    676 				xasprintf(&bp, "%s -t %s%s", cmd,
    677 				    *targ == '-' ? "-- " : "", targ);
    678 				host = cleanhostname(thost);
    679 				if (do_cmd(host, tuser, bp, &remin,
    680 				    &remout) < 0)
    681 					exit(1);
    682 				if (response() < 0)
    683 					exit(1);
    684 				free(bp);
    685 			}
    686 			source(1, argv + i);
    687 		}
    688 	}
    689 	free(arg);
    690 }
    691 
    692 void
    693 tolocal(int argc, char **argv)
    694 {
    695 	char *bp, *host, *src, *suser;
    696 	arglist alist;
    697 	int i;
    698 
    699 	memset(&alist, '\0', sizeof(alist));
    700 	alist.list = NULL;
    701 
    702 	for (i = 0; i < argc - 1; i++) {
    703 		if (!(src = colon(argv[i]))) {	/* Local to local. */
    704 			freeargs(&alist);
    705 			addargs(&alist, "%s", _PATH_CP);
    706 			if (iamrecursive)
    707 				addargs(&alist, "-r");
    708 			if (pflag)
    709 				addargs(&alist, "-p");
    710 			addargs(&alist, "--");
    711 			addargs(&alist, "%s", argv[i]);
    712 			addargs(&alist, "%s", argv[argc-1]);
    713 			if (do_local_cmd(&alist))
    714 				++errs;
    715 			continue;
    716 		}
    717 		*src++ = 0;
    718 		if (*src == 0)
    719 			src = ".";
    720 		if ((host = strrchr(argv[i], '@')) == NULL) {
    721 			host = argv[i];
    722 			suser = NULL;
    723 		} else {
    724 			*host++ = 0;
    725 			suser = argv[i];
    726 			if (*suser == '\0')
    727 				suser = pwd->pw_name;
    728 		}
    729 		host = cleanhostname(host);
    730 		xasprintf(&bp, "%s -f %s%s",
    731 		    cmd, *src == '-' ? "-- " : "", src);
    732 		if (do_cmd(host, suser, bp, &remin, &remout) < 0) {
    733 			free(bp);
    734 			++errs;
    735 			continue;
    736 		}
    737 		free(bp);
    738 		sink(1, argv + argc - 1);
    739 		(void) close(remin);
    740 		remin = remout = -1;
    741 	}
    742 }
    743 
    744 void
    745 source(int argc, char **argv)
    746 {
    747 	struct stat stb;
    748 	static BUF buffer;
    749 	BUF *bp;
    750 	off_t i, statbytes;
    751 	size_t amt, nr;
    752 	int fd = -1, haderr, indx;
    753 	char *last, *name, buf[2048], encname[PATH_MAX];
    754 	int len;
    755 
    756 	for (indx = 0; indx < argc; ++indx) {
    757 		name = argv[indx];
    758 		statbytes = 0;
    759 		len = strlen(name);
    760 		while (len > 1 && name[len-1] == '/')
    761 			name[--len] = '\0';
    762 		if ((fd = open(name, O_RDONLY|O_NONBLOCK, 0)) < 0)
    763 			goto syserr;
    764 		if (strchr(name, '\n') != NULL) {
    765 			strnvis(encname, name, sizeof(encname), VIS_NL);
    766 			name = encname;
    767 		}
    768 		if (fstat(fd, &stb) < 0) {
    769 syserr:			run_err("%s: %s", name, strerror(errno));
    770 			goto next;
    771 		}
    772 		if (stb.st_size < 0) {
    773 			run_err("%s: %s", name, "Negative file size");
    774 			goto next;
    775 		}
    776 		unset_nonblock(fd);
    777 		switch (stb.st_mode & S_IFMT) {
    778 		case S_IFREG:
    779 			break;
    780 		case S_IFDIR:
    781 			if (iamrecursive) {
    782 				rsource(name, &stb);
    783 				goto next;
    784 			}
    785 			/* FALLTHROUGH */
    786 		default:
    787 			run_err("%s: not a regular file", name);
    788 			goto next;
    789 		}
    790 		if ((last = strrchr(name, '/')) == NULL)
    791 			last = name;
    792 		else
    793 			++last;
    794 		curfile = last;
    795 		if (pflag) {
    796 			if (do_times(remout, verbose_mode, &stb) < 0)
    797 				goto next;
    798 		}
    799 #define	FILEMODEMASK	(S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO)
    800 		snprintf(buf, sizeof buf, "C%04o %lld %s\n",
    801 		    (u_int) (stb.st_mode & FILEMODEMASK),
    802 		    (long long)stb.st_size, last);
    803 		if (verbose_mode) {
    804 			fprintf(stderr, "Sending file modes: %s", buf);
    805 		}
    806 		(void) atomicio(vwrite, remout, buf, strlen(buf));
    807 		if (response() < 0)
    808 			goto next;
    809 		if ((bp = allocbuf(&buffer, fd, COPY_BUFLEN)) == NULL) {
    810 next:			if (fd != -1) {
    811 				(void) close(fd);
    812 				fd = -1;
    813 			}
    814 			continue;
    815 		}
    816 		if (showprogress)
    817 			start_progress_meter(curfile, stb.st_size, &statbytes);
    818 		set_nonblock(remout);
    819 		for (haderr = i = 0; i < stb.st_size; i += bp->cnt) {
    820 			amt = bp->cnt;
    821 			if (i + (off_t)amt > stb.st_size)
    822 				amt = stb.st_size - i;
    823 			if (!haderr) {
    824 				if ((nr = atomicio(read, fd,
    825 				    bp->buf, amt)) != amt) {
    826 					haderr = errno;
    827 					memset(bp->buf + nr, 0, amt - nr);
    828 				}
    829 			}
    830 			/* Keep writing after error to retain sync */
    831 			if (haderr) {
    832 				(void)atomicio(vwrite, remout, bp->buf, amt);
    833 				memset(bp->buf, 0, amt);
    834 				continue;
    835 			}
    836 			if (atomicio6(vwrite, remout, bp->buf, amt, scpio,
    837 			    &statbytes) != amt)
    838 				haderr = errno;
    839 		}
    840 		unset_nonblock(remout);
    841 		if (showprogress)
    842 			stop_progress_meter();
    843 
    844 		if (fd != -1) {
    845 			if (close(fd) < 0 && !haderr)
    846 				haderr = errno;
    847 			fd = -1;
    848 		}
    849 		if (!haderr)
    850 			(void) atomicio(vwrite, remout, "", 1);
    851 		else
    852 			run_err("%s: %s", name, strerror(haderr));
    853 		(void) response();
    854 	}
    855 }
    856 
    857 void
    858 rsource(char *name, struct stat *statp)
    859 {
    860 	DIR *dirp;
    861 	struct dirent *dp;
    862 	char *last, *vect[1], path[PATH_MAX];
    863 
    864 	if (!(dirp = opendir(name))) {
    865 		run_err("%s: %s", name, strerror(errno));
    866 		return;
    867 	}
    868 	last = strrchr(name, '/');
    869 	if (last == 0)
    870 		last = name;
    871 	else
    872 		last++;
    873 	if (pflag) {
    874 		if (do_times(remout, verbose_mode, statp) < 0) {
    875 			closedir(dirp);
    876 			return;
    877 		}
    878 	}
    879 	(void) snprintf(path, sizeof path, "D%04o %d %.1024s\n",
    880 	    (u_int) (statp->st_mode & FILEMODEMASK), 0, last);
    881 	if (verbose_mode)
    882 		fprintf(stderr, "Entering directory: %s", path);
    883 	(void) atomicio(vwrite, remout, path, strlen(path));
    884 	if (response() < 0) {
    885 		closedir(dirp);
    886 		return;
    887 	}
    888 	while ((dp = readdir(dirp)) != NULL) {
    889 		if (dp->d_ino == 0)
    890 			continue;
    891 		if (!strcmp(dp->d_name, ".") || !strcmp(dp->d_name, ".."))
    892 			continue;
    893 		if (strlen(name) + 1 + strlen(dp->d_name) >= sizeof(path) - 1) {
    894 			run_err("%s/%s: name too long", name, dp->d_name);
    895 			continue;
    896 		}
    897 		(void) snprintf(path, sizeof path, "%s/%s", name, dp->d_name);
    898 		vect[0] = path;
    899 		source(1, vect);
    900 	}
    901 	(void) closedir(dirp);
    902 	(void) atomicio(vwrite, remout, "E\n", 2);
    903 	(void) response();
    904 }
    905 
    906 void
    907 sink(int argc, char **argv)
    908 {
    909 	static BUF buffer;
    910 	struct stat stb;
    911 	enum {
    912 		YES, NO, DISPLAYED
    913 	} wrerr;
    914 	BUF *bp;
    915 	off_t i;
    916 	size_t j, count;
    917 	int amt, exists, first, ofd;
    918 	mode_t mode, omode, mask;
    919 	off_t size, statbytes;
    920 	unsigned long long ull;
    921 	int setimes, targisdir, wrerrno = 0;
    922 	char ch, *cp, *np, *targ, *why, *vect[1], buf[2048];
    923 	struct timeval tv[2];
    924 
    925 #define	atime	tv[0]
    926 #define	mtime	tv[1]
    927 #define	SCREWUP(str)	{ why = str; goto screwup; }
    928 
    929 	setimes = targisdir = 0;
    930 	mask = umask(0);
    931 	if (!pflag)
    932 		(void) umask(mask);
    933 	if (argc != 1) {
    934 		run_err("ambiguous target");
    935 		exit(1);
    936 	}
    937 	targ = *argv;
    938 	if (targetshouldbedirectory)
    939 		verifydir(targ);
    940 
    941 	(void) atomicio(vwrite, remout, "", 1);
    942 	if (stat(targ, &stb) == 0 && S_ISDIR(stb.st_mode))
    943 		targisdir = 1;
    944 	for (first = 1;; first = 0) {
    945 		cp = buf;
    946 		if (atomicio(read, remin, cp, 1) != 1)
    947 			return;
    948 		if (*cp++ == '\n')
    949 			SCREWUP("unexpected <newline>");
    950 		do {
    951 			if (atomicio(read, remin, &ch, sizeof(ch)) != sizeof(ch))
    952 				SCREWUP("lost connection");
    953 			*cp++ = ch;
    954 		} while (cp < &buf[sizeof(buf) - 1] && ch != '\n');
    955 		*cp = 0;
    956 		if (verbose_mode)
    957 			fprintf(stderr, "Sink: %s", buf);
    958 
    959 		if (buf[0] == '\01' || buf[0] == '\02') {
    960 			if (iamremote == 0)
    961 				(void) atomicio(vwrite, STDERR_FILENO,
    962 				    buf + 1, strlen(buf + 1));
    963 			if (buf[0] == '\02')
    964 				exit(1);
    965 			++errs;
    966 			continue;
    967 		}
    968 		if (buf[0] == 'E') {
    969 			(void) atomicio(vwrite, remout, "", 1);
    970 			return;
    971 		}
    972 		if (ch == '\n')
    973 			*--cp = 0;
    974 
    975 		cp = buf;
    976 		if (*cp == 'T') {
    977 			setimes++;
    978 			cp++;
    979 			if (!isdigit((unsigned char)*cp))
    980 				SCREWUP("mtime.sec not present");
    981 			ull = strtoull(cp, &cp, 10);
    982 			if (!cp || *cp++ != ' ')
    983 				SCREWUP("mtime.sec not delimited");
    984 			if ((time_t)ull < 0 ||
    985 			    (unsigned long long)(time_t)ull != ull)
    986 				setimes = 0;	/* out of range */
    987 			mtime.tv_sec = ull;
    988 			mtime.tv_usec = strtol(cp, &cp, 10);
    989 			if (!cp || *cp++ != ' ' || mtime.tv_usec < 0 ||
    990 			    mtime.tv_usec > 999999)
    991 				SCREWUP("mtime.usec not delimited");
    992 			if (!isdigit((unsigned char)*cp))
    993 				SCREWUP("atime.sec not present");
    994 			ull = strtoull(cp, &cp, 10);
    995 			if (!cp || *cp++ != ' ')
    996 				SCREWUP("atime.sec not delimited");
    997 			if ((time_t)ull < 0 ||
    998 			    (unsigned long long)(time_t)ull != ull)
    999 				setimes = 0;	/* out of range */
   1000 			atime.tv_sec = ull;
   1001 			atime.tv_usec = strtol(cp, &cp, 10);
   1002 			if (!cp || *cp++ != '\0' || atime.tv_usec < 0 ||
   1003 			    atime.tv_usec > 999999)
   1004 				SCREWUP("atime.usec not delimited");
   1005 			(void) atomicio(vwrite, remout, "", 1);
   1006 			continue;
   1007 		}
   1008 		if (*cp != 'C' && *cp != 'D') {
   1009 			/*
   1010 			 * Check for the case "rcp remote:foo\* local:bar".
   1011 			 * In this case, the line "No match." can be returned
   1012 			 * by the shell before the rcp command on the remote is
   1013 			 * executed so the ^Aerror_message convention isn't
   1014 			 * followed.
   1015 			 */
   1016 			if (first) {
   1017 				run_err("%s", cp);
   1018 				exit(1);
   1019 			}
   1020 			SCREWUP("expected control record");
   1021 		}
   1022 		mode = 0;
   1023 		for (++cp; cp < buf + 5; cp++) {
   1024 			if (*cp < '0' || *cp > '7')
   1025 				SCREWUP("bad mode");
   1026 			mode = (mode << 3) | (*cp - '0');
   1027 		}
   1028 		if (*cp++ != ' ')
   1029 			SCREWUP("mode not delimited");
   1030 
   1031 		for (size = 0; isdigit((unsigned char)*cp);)
   1032 			size = size * 10 + (*cp++ - '0');
   1033 		if (*cp++ != ' ')
   1034 			SCREWUP("size not delimited");
   1035 		if ((strchr(cp, '/') != NULL) || (strcmp(cp, "..") == 0)) {
   1036 			run_err("error: unexpected filename: %s", cp);
   1037 			exit(1);
   1038 		}
   1039 		if (targisdir) {
   1040 			static char *namebuf;
   1041 			static size_t cursize;
   1042 			size_t need;
   1043 
   1044 			need = strlen(targ) + strlen(cp) + 250;
   1045 			if (need > cursize) {
   1046 				free(namebuf);
   1047 				namebuf = xmalloc(need);
   1048 				cursize = need;
   1049 			}
   1050 			(void) snprintf(namebuf, need, "%s%s%s", targ,
   1051 			    strcmp(targ, "/") ? "/" : "", cp);
   1052 			np = namebuf;
   1053 		} else
   1054 			np = targ;
   1055 		curfile = cp;
   1056 		exists = stat(np, &stb) == 0;
   1057 		if (buf[0] == 'D') {
   1058 			int mod_flag = pflag;
   1059 			if (!iamrecursive)
   1060 				SCREWUP("received directory without -r");
   1061 			if (exists) {
   1062 				if (!S_ISDIR(stb.st_mode)) {
   1063 					errno = ENOTDIR;
   1064 					goto bad;
   1065 				}
   1066 				if (pflag)
   1067 					(void) chmod(np, mode);
   1068 			} else {
   1069 				/* Handle copying from a read-only
   1070 				   directory */
   1071 				mod_flag = 1;
   1072 				if (mkdir(np, mode | S_IRWXU) < 0)
   1073 					goto bad;
   1074 			}
   1075 			vect[0] = xstrdup(np);
   1076 			sink(1, vect);
   1077 			if (setimes) {
   1078 				setimes = 0;
   1079 				if (utimes(vect[0], tv) < 0)
   1080 					run_err("%s: set times: %s",
   1081 					    vect[0], strerror(errno));
   1082 			}
   1083 			if (mod_flag)
   1084 				(void) chmod(vect[0], mode);
   1085 			free(vect[0]);
   1086 			continue;
   1087 		}
   1088 		omode = mode;
   1089 		mode |= S_IWUSR;
   1090 		if ((ofd = open(np, O_WRONLY|O_CREAT, mode)) < 0) {
   1091 bad:			run_err("%s: %s", np, strerror(errno));
   1092 			continue;
   1093 		}
   1094 		(void) atomicio(vwrite, remout, "", 1);
   1095 		if ((bp = allocbuf(&buffer, ofd, COPY_BUFLEN)) == NULL) {
   1096 			(void) close(ofd);
   1097 			continue;
   1098 		}
   1099 		cp = bp->buf;
   1100 		wrerr = NO;
   1101 
   1102 		statbytes = 0;
   1103 		if (showprogress)
   1104 			start_progress_meter(curfile, size, &statbytes);
   1105 		set_nonblock(remin);
   1106 		for (count = i = 0; i < size; i += bp->cnt) {
   1107 			amt = bp->cnt;
   1108 			if (i + amt > size)
   1109 				amt = size - i;
   1110 			count += amt;
   1111 			do {
   1112 				j = atomicio6(read, remin, cp, amt,
   1113 				    scpio, &statbytes);
   1114 				if (j == 0) {
   1115 					run_err("%s", j != EPIPE ?
   1116 					    strerror(errno) :
   1117 					    "dropped connection");
   1118 					exit(1);
   1119 				}
   1120 				amt -= j;
   1121 				cp += j;
   1122 			} while (amt > 0);
   1123 
   1124 			if (count == bp->cnt) {
   1125 				/* Keep reading so we stay sync'd up. */
   1126 				if (wrerr == NO) {
   1127 					if (atomicio(vwrite, ofd, bp->buf,
   1128 					    count) != count) {
   1129 						wrerr = YES;
   1130 						wrerrno = errno;
   1131 					}
   1132 				}
   1133 				count = 0;
   1134 				cp = bp->buf;
   1135 			}
   1136 		}
   1137 		unset_nonblock(remin);
   1138 		if (showprogress)
   1139 			stop_progress_meter();
   1140 		if (count != 0 && wrerr == NO &&
   1141 		    atomicio(vwrite, ofd, bp->buf, count) != count) {
   1142 			wrerr = YES;
   1143 			wrerrno = errno;
   1144 		}
   1145 		if (wrerr == NO && (!exists || S_ISREG(stb.st_mode)) &&
   1146 		    ftruncate(ofd, size) != 0) {
   1147 			run_err("%s: truncate: %s", np, strerror(errno));
   1148 			wrerr = DISPLAYED;
   1149 		}
   1150 		if (pflag) {
   1151 			if (exists || omode != mode)
   1152 #ifdef HAVE_FCHMOD
   1153 				if (fchmod(ofd, omode)) {
   1154 #else /* HAVE_FCHMOD */
   1155 				if (chmod(np, omode)) {
   1156 #endif /* HAVE_FCHMOD */
   1157 					run_err("%s: set mode: %s",
   1158 					    np, strerror(errno));
   1159 					wrerr = DISPLAYED;
   1160 				}
   1161 		} else {
   1162 			if (!exists && omode != mode)
   1163 #ifdef HAVE_FCHMOD
   1164 				if (fchmod(ofd, omode & ~mask)) {
   1165 #else /* HAVE_FCHMOD */
   1166 				if (chmod(np, omode & ~mask)) {
   1167 #endif /* HAVE_FCHMOD */
   1168 					run_err("%s: set mode: %s",
   1169 					    np, strerror(errno));
   1170 					wrerr = DISPLAYED;
   1171 				}
   1172 		}
   1173 		if (close(ofd) == -1) {
   1174 			wrerr = YES;
   1175 			wrerrno = errno;
   1176 		}
   1177 		(void) response();
   1178 		if (setimes && wrerr == NO) {
   1179 			setimes = 0;
   1180 			if (utimes(np, tv) < 0) {
   1181 				run_err("%s: set times: %s",
   1182 				    np, strerror(errno));
   1183 				wrerr = DISPLAYED;
   1184 			}
   1185 		}
   1186 		switch (wrerr) {
   1187 		case YES:
   1188 			run_err("%s: %s", np, strerror(wrerrno));
   1189 			break;
   1190 		case NO:
   1191 			(void) atomicio(vwrite, remout, "", 1);
   1192 			break;
   1193 		case DISPLAYED:
   1194 			break;
   1195 		}
   1196 	}
   1197 screwup:
   1198 	run_err("protocol error: %s", why);
   1199 	exit(1);
   1200 }
   1201 
   1202 int
   1203 response(void)
   1204 {
   1205 	char ch, *cp, resp, rbuf[2048];
   1206 
   1207 	if (atomicio(read, remin, &resp, sizeof(resp)) != sizeof(resp))
   1208 		lostconn(0);
   1209 
   1210 	cp = rbuf;
   1211 	switch (resp) {
   1212 	case 0:		/* ok */
   1213 		return (0);
   1214 	default:
   1215 		*cp++ = resp;
   1216 		/* FALLTHROUGH */
   1217 	case 1:		/* error, followed by error msg */
   1218 	case 2:		/* fatal error, "" */
   1219 		do {
   1220 			if (atomicio(read, remin, &ch, sizeof(ch)) != sizeof(ch))
   1221 				lostconn(0);
   1222 			*cp++ = ch;
   1223 		} while (cp < &rbuf[sizeof(rbuf) - 1] && ch != '\n');
   1224 
   1225 		if (!iamremote)
   1226 			(void) atomicio(vwrite, STDERR_FILENO, rbuf, cp - rbuf);
   1227 		++errs;
   1228 		if (resp == 1)
   1229 			return (-1);
   1230 		exit(1);
   1231 	}
   1232 	/* NOTREACHED */
   1233 }
   1234 
   1235 void
   1236 usage(void)
   1237 {
   1238 	(void) fprintf(stderr,
   1239 	    "usage: scp [-12346BCpqrv] [-c cipher] [-F ssh_config] [-i identity_file]\n"
   1240 	    "           [-l limit] [-o ssh_option] [-P port] [-S program]\n"
   1241 	    "           [[user@]host1:]file1 ... [[user@]host2:]file2\n");
   1242 	exit(1);
   1243 }
   1244 
   1245 void
   1246 run_err(const char *fmt,...)
   1247 {
   1248 	static FILE *fp;
   1249 	va_list ap;
   1250 
   1251 	++errs;
   1252 	if (fp != NULL || (remout != -1 && (fp = fdopen(remout, "w")))) {
   1253 		(void) fprintf(fp, "%c", 0x01);
   1254 		(void) fprintf(fp, "scp: ");
   1255 		va_start(ap, fmt);
   1256 		(void) vfprintf(fp, fmt, ap);
   1257 		va_end(ap);
   1258 		(void) fprintf(fp, "\n");
   1259 		(void) fflush(fp);
   1260 	}
   1261 
   1262 	if (!iamremote) {
   1263 		va_start(ap, fmt);
   1264 		vfprintf(stderr, fmt, ap);
   1265 		va_end(ap);
   1266 		fprintf(stderr, "\n");
   1267 	}
   1268 }
   1269 
   1270 void
   1271 verifydir(char *cp)
   1272 {
   1273 	struct stat stb;
   1274 
   1275 	if (!stat(cp, &stb)) {
   1276 		if (S_ISDIR(stb.st_mode))
   1277 			return;
   1278 		errno = ENOTDIR;
   1279 	}
   1280 	run_err("%s: %s", cp, strerror(errno));
   1281 	killchild(0);
   1282 }
   1283 
   1284 int
   1285 okname(char *cp0)
   1286 {
   1287 	int c;
   1288 	char *cp;
   1289 
   1290 	cp = cp0;
   1291 	do {
   1292 		c = (int)*cp;
   1293 		if (c & 0200)
   1294 			goto bad;
   1295 		if (!isalpha(c) && !isdigit((unsigned char)c)) {
   1296 			switch (c) {
   1297 			case '\'':
   1298 			case '"':
   1299 			case '`':
   1300 			case ' ':
   1301 			case '#':
   1302 				goto bad;
   1303 			default:
   1304 				break;
   1305 			}
   1306 		}
   1307 	} while (*++cp);
   1308 	return (1);
   1309 
   1310 bad:	fprintf(stderr, "%s: invalid user name\n", cp0);
   1311 	return (0);
   1312 }
   1313 
   1314 BUF *
   1315 allocbuf(BUF *bp, int fd, int blksize)
   1316 {
   1317 	size_t size;
   1318 #ifdef HAVE_STRUCT_STAT_ST_BLKSIZE
   1319 	struct stat stb;
   1320 
   1321 	if (fstat(fd, &stb) < 0) {
   1322 		run_err("fstat: %s", strerror(errno));
   1323 		return (0);
   1324 	}
   1325 	size = roundup(stb.st_blksize, blksize);
   1326 	if (size == 0)
   1327 		size = blksize;
   1328 #else /* HAVE_STRUCT_STAT_ST_BLKSIZE */
   1329 	size = blksize;
   1330 #endif /* HAVE_STRUCT_STAT_ST_BLKSIZE */
   1331 	if (bp->cnt >= size)
   1332 		return (bp);
   1333 	if (bp->buf == NULL)
   1334 		bp->buf = xmalloc(size);
   1335 	else
   1336 		bp->buf = xreallocarray(bp->buf, 1, size);
   1337 	memset(bp->buf, 0, size);
   1338 	bp->cnt = size;
   1339 	return (bp);
   1340 }
   1341 
   1342 void
   1343 lostconn(int signo)
   1344 {
   1345 	if (!iamremote)
   1346 		(void)write(STDERR_FILENO, "lost connection\n", 16);
   1347 	if (signo)
   1348 		_exit(1);
   1349 	else
   1350 		exit(1);
   1351 }
   1352