bin/rcp/rcp.c

   1 /*-
   2  * Copyright (c) 1983, 1990, 1992, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  * Copyright (c) 2002 Networks Associates Technology, Inc.
   5  * All rights reserved.
   6  *
   7  * Portions of this software were developed for the FreeBSD Project by
   8  * ThinkSec AS and NAI Labs, the Security Research Division of Network
   9  * Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
  10  * ("CBOSS"), as part of the DARPA CHATS research program.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions and the following disclaimer.
  17  * 2. Redistributions in binary form must reproduce the above copyright
  18  *    notice, this list of conditions and the following disclaimer in the
  19  *    documentation and/or other materials provided with the distribution.
  20  * 4. Neither the name of the University nor the names of its contributors
  21  *    may be used to endorse or promote products derived from this software
  22  *    without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  */
  36
  37 #if 0
  38 #ifndef lint
  39 static char const copyright[] =
  40 "@(#) Copyright (c) 1983, 1990, 1992, 1993\n\
  41         The Regents of the University of California.  All rights reserved.\n";
  42 #endif /* not lint */
  43
  44 #ifndef lint
  45 static char sccsid[] = "@(#)rcp.c       8.2 (Berkeley) 4/2/94";
  46 #endif /* not lint */
  47 #endif
  48 #include <sys/cdefs.h>
  49 __FBSDID("$FreeBSD$");
  50
  51 #include <sys/param.h>
  52 #include <sys/stat.h>
  53 #include <sys/time.h>
  54 #include <sys/socket.h>
  55 #include <netinet/in.h>
  56 #include <netinet/in_systm.h>
  57 #include <netinet/ip.h>
  58
  59 #include <ctype.h>
  60 #include <dirent.h>
  61 #include <err.h>
  62 #include <errno.h>
  63 #include <fcntl.h>
  64 #include <libutil.h>
  65 #include <limits.h>
  66 #include <netdb.h>
  67 #include <paths.h>
  68 #include <pwd.h>
  69 #include <signal.h>
  70 #include <stdint.h>
  71 #include <stdio.h>
  72 #include <stdlib.h>
  73 #include <string.h>
  74 #include <string.h>
  75 #include <unistd.h>
  76
  77 #include "extern.h"
  78
  79 #define OPTIONS "46dfprt"
  80
  81 struct passwd *pwd;
  82 u_short port;
  83 uid_t   userid;
  84 int errs, rem;
  85 int pflag, iamremote, iamrecursive, targetshouldbedirectory;
  86 int family = PF_UNSPEC;
  87
  88 static int argc_copy;
  89 static const char **argv_copy;
  90
  91 static char period[] = ".";
  92
  93 #define CMDNEEDS        64
  94 char cmd[CMDNEEDS];             /* must hold "rcp -r -p -d\0" */
  95
  96 int      response(void);
  97 void     rsource(char *, struct stat *);
  98 void     sink(int, char *[]);
  99 void     source(int, char *[]);
 100 void     tolocal(int, char *[]);
 101 void     toremote(char *, int, char *[]);
 102 void     usage(void);
 103
 104 int
 105 main(int argc, char *argv[])
 106 {
 107         struct servent *sp;
 108         int ch, fflag, i, tflag;
 109         char *targ;
 110
 111         /*
 112          * Prepare for execing ourselves.
 113          */
 114         argc_copy = argc + 1;
 115         argv_copy = malloc((argc_copy + 1) * sizeof(*argv_copy));
 116         if (argv_copy == NULL)
 117                 err(1, "malloc");
 118         argv_copy[0] = argv[0];
 119         argv_copy[1] = "-K";
 120         for (i = 1; i < argc; ++i) {
 121                 argv_copy[i + 1] = strdup(argv[i]);
 122                 if (argv_copy[i + 1] == NULL)
 123                         errx(1, "strdup: out of memory");
 124         }
 125         argv_copy[argc + 1] = NULL;
 126
 127         fflag = tflag = 0;
 128         while ((ch = getopt(argc, argv, OPTIONS)) != -1)
 129                 switch(ch) {                    /* User-visible flags. */
 130                 case '4':
 131                         family = PF_INET;
 132                         break;
 133
 134                 case '6':
 135                         family = PF_INET6;
 136                         break;
 137
 138                 case 'p':
 139                         pflag = 1;
 140                         break;
 141                 case 'r':
 142                         iamrecursive = 1;
 143                         break;
 144                                                 /* Server options. */
 145                 case 'd':
 146                         targetshouldbedirectory = 1;
 147                         break;
 148                 case 'f':                       /* "from" */
 149                         iamremote = 1;
 150                         fflag = 1;
 151                         break;
 152                 case 't':                       /* "to" */
 153                         iamremote = 1;
 154                         tflag = 1;
 155                         break;
 156                 case '?':
 157                 default:
 158                         usage();
 159                 }
 160         argc -= optind;
 161         argv += optind;
 162
 163         sp = getservbyname("shell", "tcp");
 164         if (sp == NULL)
 165                 errx(1, "shell/tcp: unknown service");
 166         port = sp->s_port;
 167
 168         if ((pwd = getpwuid(userid = getuid())) == NULL)
 169                 errx(1, "unknown user %d", (int)userid);
 170
 171         rem = STDIN_FILENO;             /* XXX */
 172
 173         if (fflag) {                    /* Follow "protocol", send data. */
 174                 (void)response();
 175                 (void)setuid(userid);
 176                 source(argc, argv);
 177                 exit(errs);
 178         }
 179
 180         if (tflag) {                    /* Receive data. */
 181                 (void)setuid(userid);
 182                 sink(argc, argv);
 183                 exit(errs);
 184         }
 185
 186         if (argc < 2)
 187                 usage();
 188         if (argc > 2)
 189                 targetshouldbedirectory = 1;
 190
 191         rem = -1;
 192         /* Command to be executed on remote system using "rsh". */
 193         (void)snprintf(cmd, sizeof(cmd), "rcp%s%s%s",
 194             iamrecursive ? " -r" : "", pflag ? " -p" : "",
 195             targetshouldbedirectory ? " -d" : "");
 196
 197         (void)signal(SIGPIPE, lostconn);
 198
 199         if ((targ = colon(argv[argc - 1])))     /* Dest is remote host. */
 200                 toremote(targ, argc, argv);
 201         else {
 202                 tolocal(argc, argv);            /* Dest is local host. */
 203                 if (targetshouldbedirectory)
 204                         verifydir(argv[argc - 1]);
 205         }
 206         exit(errs);
 207 }
 208
 209 void
 210 toremote(char *targ, int argc, char *argv[])
 211 {
 212         int i, tos;
 213         char *bp, *host, *src, *suser, *thost, *tuser;
 214
 215         *targ++ = 0;
 216         if (*targ == 0)
 217                 targ = period;
 218
 219         if ((thost = strchr(argv[argc - 1], '@'))) {
 220                 /* user@host */
 221                 *thost++ = 0;
 222                 tuser = argv[argc - 1];
 223                 if (*tuser == '\0')
 224                         tuser = NULL;
 225                 else if (!okname(tuser))
 226                         exit(1);
 227         } else {
 228                 thost = argv[argc - 1];
 229                 tuser = NULL;
 230         }
 231
 232         for (i = 0; i < argc - 1; i++) {
 233                 src = colon(argv[i]);
 234                 if (src) {                      /* remote to remote */
 235                         *src++ = 0;
 236                         if (*src == 0)
 237                                 src = period;
 238                         host = strchr(argv[i], '@');
 239                         if (host) {
 240                                 *host++ = 0;
 241                                 suser = argv[i];
 242                                 if (*suser == '\0')
 243                                         suser = pwd->pw_name;
 244                                 else if (!okname(suser)) {
 245                                         ++errs;
 246                                         continue;
 247                                 }
 248                                 if (asprintf(&bp,
 249                                     "%s %s -l %s -n %s %s '%s%s%s:%s'",
 250                                     _PATH_RSH, host, suser, cmd, src,
 251                                     tuser ? tuser : "", tuser ? "@" : "",
 252                                     thost, targ) == -1)
 253                                         err(1, "asprintf");
 254                         } else
 255                                 if (asprintf(&bp,
 256                                     "exec %s %s -n %s %s '%s%s%s:%s'",
 257                                     _PATH_RSH, argv[i], cmd, src,
 258                                     tuser ? tuser : "", tuser ? "@" : "",
 259                                     thost, targ) == -1)
 260                                         err(1, "asprintf");
 261                         (void)susystem(bp, userid);
 262                         (void)free(bp);
 263                 } else {                        /* local to remote */
 264                         if (rem == -1) {
 265                                 if (asprintf(&bp, "%s -t %s", cmd, targ)
 266                                         == -1)
 267                                         err(1, "asprintf");
 268                                 host = thost;
 269                                 rem = rcmd_af(&host, port,
 270                                     pwd->pw_name,
 271                                     tuser ? tuser : pwd->pw_name,
 272                                     bp, 0, family);
 273                                 if (rem < 0)
 274                                         exit(1);
 275                                 if (family == PF_INET) {
 276                                         tos = IPTOS_THROUGHPUT;
 277                                         if (setsockopt(rem, IPPROTO_IP, IP_TOS,
 278                                             &tos, sizeof(int)) < 0)
 279                                                 warn("TOS (ignored)");
 280                                 }
 281                                 if (response() < 0)
 282                                         exit(1);
 283                                 (void)free(bp);
 284                                 (void)setuid(userid);
 285                         }
 286                         source(1, argv+i);
 287                 }
 288         }
 289 }
 290
 291 void
 292 tolocal(int argc, char *argv[])
 293 {
 294         int i, len, tos;
 295         char *bp, *host, *src, *suser;
 296
 297         for (i = 0; i < argc - 1; i++) {
 298                 if (!(src = colon(argv[i]))) {          /* Local to local. */
 299                         len = strlen(_PATH_CP) + strlen(argv[i]) +
 300                             strlen(argv[argc - 1]) + 20;
 301                         if (!(bp = malloc(len)))
 302                                 err(1, "malloc");
 303                         (void)snprintf(bp, len, "exec %s%s%s %s %s", _PATH_CP,
 304                             iamrecursive ? " -PR" : "", pflag ? " -p" : "",
 305                             argv[i], argv[argc - 1]);
 306                         if (susystem(bp, userid))
 307                                 ++errs;
 308                         (void)free(bp);
 309                         continue;
 310                 }
 311                 *src++ = 0;
 312                 if (*src == 0)
 313                         src = period;
 314                 if ((host = strchr(argv[i], '@')) == NULL) {
 315                         host = argv[i];
 316                         suser = pwd->pw_name;
 317                 } else {
 318                         *host++ = 0;
 319                         suser = argv[i];
 320                         if (*suser == '\0')
 321                                 suser = pwd->pw_name;
 322                         else if (!okname(suser)) {
 323                                 ++errs;
 324                                 continue;
 325                         }
 326                 }
 327                 len = strlen(src) + CMDNEEDS + 20;
 328                 if ((bp = malloc(len)) == NULL)
 329                         err(1, "malloc");
 330                 (void)snprintf(bp, len, "%s -f %s", cmd, src);
 331                 rem = rcmd_af(&host, port, pwd->pw_name, suser, bp, 0,
 332                             family);
 333                 (void)free(bp);
 334                 if (rem < 0) {
 335                         ++errs;
 336                         continue;
 337                 }
 338                 (void)seteuid(userid);
 339                 if (family == PF_INET) {
 340                         tos = IPTOS_THROUGHPUT;
 341                         if (setsockopt(rem, IPPROTO_IP, IP_TOS, &tos,
 342                             sizeof(int)) < 0)
 343                                 warn("TOS (ignored)");
 344                 }
 345                 sink(1, argv + argc - 1);
 346                 (void)seteuid(0);
 347                 (void)close(rem);
 348                 rem = -1;
 349         }
 350 }
 351
 352 void
 353 source(int argc, char *argv[])
 354 {
 355         struct stat stb;
 356         static BUF buffer;
 357         BUF *bp;
 358         off_t i;
 359         int amt, fd, haderr, indx, result;
 360         char *last, *name, buf[BUFSIZ];
 361
 362         for (indx = 0; indx < argc; ++indx) {
 363                 name = argv[indx];
 364                 if ((fd = open(name, O_RDONLY, 0)) < 0)
 365                         goto syserr;
 366                 if (fstat(fd, &stb)) {
 367 syserr:                 run_err("%s: %s", name, strerror(errno));
 368                         goto next;
 369                 }
 370                 switch (stb.st_mode & S_IFMT) {
 371                 case S_IFREG:
 372                         break;
 373                 case S_IFDIR:
 374                         if (iamrecursive) {
 375                                 rsource(name, &stb);
 376                                 goto next;
 377                         }
 378                         /* FALLTHROUGH */
 379                 default:
 380                         run_err("%s: not a regular file", name);
 381                         goto next;
 382                 }
 383                 if ((last = strrchr(name, '/')) == NULL)
 384                         last = name;
 385                 else
 386                         ++last;
 387                 if (pflag) {
 388                         /*
 389                          * Make it compatible with possible future
 390                          * versions expecting microseconds.
 391                          */
 392                         (void)snprintf(buf, sizeof(buf), "T%ld 0 %ld 0\n",
 393                             (long)stb.st_mtimespec.tv_sec,
 394                             (long)stb.st_atimespec.tv_sec);
 395                         (void)write(rem, buf, strlen(buf));
 396                         if (response() < 0)
 397                                 goto next;
 398                 }
 399 #define MODEMASK        (S_ISUID|S_ISGID|S_ISTXT|S_IRWXU|S_IRWXG|S_IRWXO)
 400                 (void)snprintf(buf, sizeof(buf), "C%04o %jd %s\n",
 401                     stb.st_mode & MODEMASK, (intmax_t)stb.st_size, last);
 402                 (void)write(rem, buf, strlen(buf));
 403                 if (response() < 0)
 404                         goto next;
 405                 if ((bp = allocbuf(&buffer, fd, BUFSIZ)) == NULL) {
 406 next:                   if (fd >= 0)
 407                                 (void)close(fd);
 408                         continue;
 409                 }
 410
 411                 /* Keep writing after an error so that we stay sync'd up. */
 412                 for (haderr = i = 0; i < stb.st_size; i += bp->cnt) {
 413                         amt = bp->cnt;
 414                         if (i + amt > stb.st_size)
 415                                 amt = stb.st_size - i;
 416                         if (!haderr) {
 417                                 result = read(fd, bp->buf, amt);
 418                                 if (result != amt)
 419                                         haderr = result >= 0 ? EIO : errno;
 420                         }
 421                         if (haderr)
 422                                 (void)write(rem, bp->buf, amt);
 423                         else {
 424                                 result = write(rem, bp->buf, amt);
 425                                 if (result != amt)
 426                                         haderr = result >= 0 ? EIO : errno;
 427                         }
 428                 }
 429                 if (close(fd) && !haderr)
 430                         haderr = errno;
 431                 if (!haderr)
 432                         (void)write(rem, "", 1);
 433                 else
 434                         run_err("%s: %s", name, strerror(haderr));
 435                 (void)response();
 436         }
 437 }
 438
 439 void
 440 rsource(char *name, struct stat *statp)
 441 {
 442         DIR *dirp;
 443         struct dirent *dp;
 444         char *last, *vect[1], path[PATH_MAX];
 445
 446         if (!(dirp = opendir(name))) {
 447                 run_err("%s: %s", name, strerror(errno));
 448                 return;
 449         }
 450         last = strrchr(name, '/');
 451         if (last == 0)
 452                 last = name;
 453         else
 454                 last++;
 455         if (pflag) {
 456                 (void)snprintf(path, sizeof(path), "T%ld 0 %ld 0\n",
 457                     (long)statp->st_mtimespec.tv_sec,
 458                     (long)statp->st_atimespec.tv_sec);
 459                 (void)write(rem, path, strlen(path));
 460                 if (response() < 0) {
 461                         closedir(dirp);
 462                         return;
 463                 }
 464         }
 465         (void)snprintf(path, sizeof(path),
 466             "D%04o %d %s\n", statp->st_mode & MODEMASK, 0, last);
 467         (void)write(rem, path, strlen(path));
 468         if (response() < 0) {
 469                 closedir(dirp);
 470                 return;
 471         }
 472         while ((dp = readdir(dirp))) {
 473                 if (dp->d_ino == 0)
 474                         continue;
 475                 if (!strcmp(dp->d_name, ".") || !strcmp(dp->d_name, ".."))
 476                         continue;
 477                 if (strlen(name) + 1 + strlen(dp->d_name) >= sizeof(path)) {
 478                         run_err("%s/%s: name too long", name, dp->d_name);
 479                         continue;
 480                 }
 481                 (void)snprintf(path, sizeof(path), "%s/%s", name, dp->d_name);
 482                 vect[0] = path;
 483                 source(1, vect);
 484         }
 485         (void)closedir(dirp);
 486         (void)write(rem, "E\n", 2);
 487         (void)response();
 488 }
 489
 490 void
 491 sink(int argc, char *argv[])
 492 {
 493         static BUF buffer;
 494         struct stat stb;
 495         struct timeval tv[2];
 496         enum { YES, NO, DISPLAYED } wrerr;
 497         BUF *bp;
 498         off_t i, j, size;
 499         int amt, exists, first, mask, mode, ofd, omode;
 500         size_t count;
 501         int setimes, targisdir, wrerrno = 0;
 502         char ch, *cp, *np, *targ, *vect[1], buf[BUFSIZ], path[PATH_MAX];
 503         const char *why;
 504
 505 #define atime   tv[0]
 506 #define mtime   tv[1]
 507 #define SCREWUP(str)    { why = str; goto screwup; }
 508
 509         setimes = targisdir = 0;
 510         mask = umask(0);
 511         if (!pflag)
 512                 (void)umask(mask);
 513         if (argc != 1) {
 514                 run_err("ambiguous target");
 515                 exit(1);
 516         }
 517         targ = *argv;
 518         if (targetshouldbedirectory)
 519                 verifydir(targ);
 520         (void)write(rem, "", 1);
 521         if (stat(targ, &stb) == 0 && S_ISDIR(stb.st_mode))
 522                 targisdir = 1;
 523         for (first = 1;; first = 0) {
 524                 cp = buf;
 525                 if (read(rem, cp, 1) <= 0)
 526                         return;
 527                 if (*cp++ == '\n')
 528                         SCREWUP("unexpected <newline>");
 529                 do {
 530                         if (read(rem, &ch, sizeof(ch)) != sizeof(ch))
 531                                 SCREWUP("lost connection");
 532                         *cp++ = ch;
 533                 } while (cp < &buf[BUFSIZ - 1] && ch != '\n');
 534                 *cp = 0;
 535
 536                 if (buf[0] == '\01' || buf[0] == '\02') {
 537                         if (iamremote == 0)
 538                                 (void)write(STDERR_FILENO,
 539                                     buf + 1, strlen(buf + 1));
 540                         if (buf[0] == '\02')
 541                                 exit(1);
 542                         ++errs;
 543                         continue;
 544                 }
 545                 if (buf[0] == 'E') {
 546                         (void)write(rem, "", 1);
 547                         return;
 548                 }
 549
 550                 if (ch == '\n')
 551                         *--cp = 0;
 552
 553                 cp = buf;
 554                 if (*cp == 'T') {
 555                         setimes++;
 556                         cp++;
 557                         mtime.tv_sec = strtol(cp, &cp, 10);
 558                         if (!cp || *cp++ != ' ')
 559                                 SCREWUP("mtime.sec not delimited");
 560                         mtime.tv_usec = strtol(cp, &cp, 10);
 561                         if (!cp || *cp++ != ' ')
 562                                 SCREWUP("mtime.usec not delimited");
 563                         atime.tv_sec = strtol(cp, &cp, 10);
 564                         if (!cp || *cp++ != ' ')
 565                                 SCREWUP("atime.sec not delimited");
 566                         atime.tv_usec = strtol(cp, &cp, 10);
 567                         if (!cp || *cp++ != '\0')
 568                                 SCREWUP("atime.usec not delimited");
 569                         (void)write(rem, "", 1);
 570                         continue;
 571                 }
 572                 if (*cp != 'C' && *cp != 'D') {
 573                         /*
 574                          * Check for the case "rcp remote:foo\* local:bar".
 575                          * In this case, the line "No match." can be returned
 576                          * by the shell before the rcp command on the remote is
 577                          * executed so the ^Aerror_message convention isn't
 578                          * followed.
 579                          */
 580                         if (first) {
 581                                 run_err("%s", cp);
 582                                 exit(1);
 583                         }
 584                         SCREWUP("expected control record");
 585                 }
 586                 mode = 0;
 587                 for (++cp; cp < buf + 5; cp++) {
 588                         if (*cp < '0' || *cp > '7')
 589                                 SCREWUP("bad mode");
 590                         mode = (mode << 3) | (*cp - '0');
 591                 }
 592                 if (*cp++ != ' ')
 593                         SCREWUP("mode not delimited");
 594
 595                 for (size = 0; isdigit(*cp);)
 596                         size = size * 10 + (*cp++ - '0');
 597                 if (*cp++ != ' ')
 598                         SCREWUP("size not delimited");
 599                 if (targisdir) {
 600                         if (strlen(targ) + (*targ ? 1 : 0) + strlen(cp)
 601                                         >= sizeof(path)) {
 602                                 run_err("%s%s%s: name too long", targ,
 603                                         *targ ? "/" : "", cp);
 604                                 exit(1);
 605                         }
 606                         (void)snprintf(path, sizeof(path), "%s%s%s", targ,
 607                             *targ ? "/" : "", cp);
 608                         np = path;
 609                 } else
 610                         np = targ;
 611                 exists = stat(np, &stb) == 0;
 612                 if (buf[0] == 'D') {
 613                         int mod_flag = pflag;
 614                         if (exists) {
 615                                 if (!S_ISDIR(stb.st_mode)) {
 616                                         errno = ENOTDIR;
 617                                         goto bad;
 618                                 }
 619                                 if (pflag)
 620                                         (void)chmod(np, mode);
 621                         } else {
 622                                 /* Handle copying from a read-only directory */
 623                                 mod_flag = 1;
 624                                 if (mkdir(np, mode | S_IRWXU) < 0)
 625                                         goto bad;
 626                         }
 627                         vect[0] = np;
 628                         sink(1, vect);
 629                         if (setimes) {
 630                                 setimes = 0;
 631                                 if (utimes(np, tv) < 0)
 632                                     run_err("%s: set times: %s",
 633                                         np, strerror(errno));
 634                         }
 635                         if (mod_flag)
 636                                 (void)chmod(np, mode);
 637                         continue;
 638                 }
 639                 omode = mode;
 640                 mode |= S_IWRITE;
 641                 if ((ofd = open(np, O_WRONLY|O_CREAT, mode)) < 0) {
 642 bad:                    run_err("%s: %s", np, strerror(errno));
 643                         continue;
 644                 }
 645                 (void)write(rem, "", 1);
 646                 if ((bp = allocbuf(&buffer, ofd, BUFSIZ)) == NULL) {
 647                         (void)close(ofd);
 648                         continue;
 649                 }
 650                 cp = bp->buf;
 651                 wrerr = NO;
 652                 for (count = i = 0; i < size; i += BUFSIZ) {
 653                         amt = BUFSIZ;
 654                         if (i + amt > size)
 655                                 amt = size - i;
 656                         count += amt;
 657                         do {
 658                                 j = read(rem, cp, amt);
 659                                 if (j <= 0) {
 660                                         run_err("%s", j ? strerror(errno) :
 661                                             "dropped connection");
 662                                         exit(1);
 663                                 }
 664                                 amt -= j;
 665                                 cp += j;
 666                         } while (amt > 0);
 667                         if (count == bp->cnt) {
 668                                 /* Keep reading so we stay sync'd up. */
 669                                 if (wrerr == NO) {
 670                                         j = write(ofd, bp->buf, count);
 671                                         if (j != (off_t)count) {
 672                                                 wrerr = YES;
 673                                                 wrerrno = j >= 0 ? EIO : errno;
 674                                         }
 675                                 }
 676                                 count = 0;
 677                                 cp = bp->buf;
 678                         }
 679                 }
 680                 if (count != 0 && wrerr == NO &&
 681                     (j = write(ofd, bp->buf, count)) != (off_t)count) {
 682                         wrerr = YES;
 683                         wrerrno = j >= 0 ? EIO : errno;
 684                 }
 685                 if (ftruncate(ofd, size)) {
 686                         run_err("%s: truncate: %s", np, strerror(errno));
 687                         wrerr = DISPLAYED;
 688                 }
 689                 if (pflag) {
 690                         if (exists || omode != mode)
 691                                 if (fchmod(ofd, omode))
 692                                         run_err("%s: set mode: %s",
 693                                             np, strerror(errno));
 694                 } else {
 695                         if (!exists && omode != mode)
 696                                 if (fchmod(ofd, omode & ~mask))
 697                                         run_err("%s: set mode: %s",
 698                                             np, strerror(errno));
 699                 }
 700                 (void)close(ofd);
 701                 (void)response();
 702                 if (setimes && wrerr == NO) {
 703                         setimes = 0;
 704                         if (utimes(np, tv) < 0) {
 705                                 run_err("%s: set times: %s",
 706                                     np, strerror(errno));
 707                                 wrerr = DISPLAYED;
 708                         }
 709                 }
 710                 switch(wrerr) {
 711                 case YES:
 712                         run_err("%s: %s", np, strerror(wrerrno));
 713                         break;
 714                 case NO:
 715                         (void)write(rem, "", 1);
 716                         break;
 717                 case DISPLAYED:
 718                         break;
 719                 }
 720         }
 721 screwup:
 722         run_err("protocol error: %s", why);
 723         exit(1);
 724 }
 725
 726 int
 727 response(void)
 728 {
 729         char ch, *cp, resp, rbuf[BUFSIZ];
 730
 731         if (read(rem, &resp, sizeof(resp)) != sizeof(resp))
 732                 lostconn(0);
 733
 734         cp = rbuf;
 735         switch(resp) {
 736         case 0:                         /* ok */
 737                 return (0);
 738         default:
 739                 *cp++ = resp;
 740                 /* FALLTHROUGH */
 741         case 1:                         /* error, followed by error msg */
 742         case 2:                         /* fatal error, "" */
 743                 do {
 744                         if (read(rem, &ch, sizeof(ch)) != sizeof(ch))
 745                                 lostconn(0);
 746                         *cp++ = ch;
 747                 } while (cp < &rbuf[BUFSIZ] && ch != '\n');
 748
 749                 if (!iamremote)
 750                         (void)write(STDERR_FILENO, rbuf, cp - rbuf);
 751                 ++errs;
 752                 if (resp == 1)
 753                         return (-1);
 754                 exit(1);
 755         }
 756         /* NOTREACHED */
 757 }
 758
 759 void
 760 usage(void)
 761 {
 762         (void)fprintf(stderr, "%s\n%s\n",
 763             "usage: rcp [-46p] file1 file2",
 764             "       rcp [-46pr] file ... directory");
 765         exit(1);
 766 }
 767
 768 #include <stdarg.h>
 769
 770 void
 771 run_err(const char *fmt, ...)
 772 {
 773         static FILE *fp;
 774         va_list ap;
 775
 776         ++errs;
 777         if (fp == NULL && !(fp = fdopen(rem, "w")))
 778                 return;
 779         (void)fprintf(fp, "%c", 0x01);
 780         (void)fprintf(fp, "rcp: ");
 781         va_start(ap, fmt);
 782         (void)vfprintf(fp, fmt, ap);
 783         va_end(ap);
 784         (void)fprintf(fp, "\n");
 785         (void)fflush(fp);
 786
 787         if (!iamremote) {
 788                 va_start(ap, fmt);
 789                 vwarnx(fmt, ap);
 790                 va_end(ap);
 791         }
 792 }