rsh.c revision 1.4
1 /* $NetBSD: rsh.c,v 1.4 1997/01/09 20:21:15 tls Exp $ */ 2 3 /*- 4 * Copyright (c) 1983, 1990 The Regents of the University of California. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #ifndef lint 37 char copyright[] = 38 "@(#) Copyright (c) 1983, 1990 The Regents of the University of California.\n\ 39 All rights reserved.\n"; 40 #endif /* not lint */ 41 42 #ifndef lint 43 /*static char sccsid[] = "from: @(#)rsh.c 5.24 (Berkeley) 7/1/91";*/ 44 static char rcsid[] = "$NetBSD: rsh.c,v 1.4 1997/01/09 20:21:15 tls Exp $"; 45 #endif /* not lint */ 46 47 /* 48 * $Source: /tank/opengrok/rsync2/NetBSD/src/usr.bin/rsh/rsh.c,v $ 49 * $Header: /tank/opengrok/rsync2/NetBSD/src/usr.bin/rsh/rsh.c,v 1.4 1997/01/09 20:21:15 tls Exp $ 50 */ 51 52 #include <sys/types.h> 53 #include <sys/socket.h> 54 #include <sys/ioctl.h> 55 #include <sys/file.h> 56 57 #include <netinet/in.h> 58 #include <netdb.h> 59 60 #include <pwd.h> 61 #include <signal.h> 62 #include <stdio.h> 63 #include <errno.h> 64 #include <string.h> 65 #include <varargs.h> 66 #include "pathnames.h" 67 68 #ifdef KERBEROS 69 #include <kerberosIV/des.h> 70 #include <kerberosIV/krb.h> 71 72 CREDENTIALS cred; 73 Key_schedule schedule; 74 int use_kerberos = 1, doencrypt; 75 char dst_realm_buf[REALM_SZ], *dest_realm; 76 extern char *krb_realmofhost(); 77 #endif 78 79 /* 80 * rsh - remote shell 81 */ 82 extern int errno; 83 int rfd2; 84 85 main(argc, argv) 86 int argc; 87 char **argv; 88 { 89 extern char *optarg; 90 extern int optind; 91 struct passwd *pw; 92 struct servent *sp; 93 long omask; 94 int argoff, asrsh, ch, dflag, nflag, one, pid, rem, uid; 95 register char *p; 96 char *args, *host, *user, *copyargs(); 97 void sendsig(); 98 99 argoff = asrsh = dflag = nflag = 0; 100 one = 1; 101 host = user = NULL; 102 103 /* if called as something other than "rsh", use it as the host name */ 104 if (p = rindex(argv[0], '/')) 105 ++p; 106 else 107 p = argv[0]; 108 if (strcmp(p, "rsh")) 109 host = p; 110 else 111 asrsh = 1; 112 113 /* handle "rsh host flags" */ 114 if (!host && argc > 2 && argv[1][0] != '-') { 115 host = argv[1]; 116 argoff = 1; 117 } 118 119 #ifdef KERBEROS 120 #ifdef CRYPT 121 #define OPTIONS "8KLdek:l:nwx" 122 #else 123 #define OPTIONS "8KLdek:l:nw" 124 #endif 125 #else 126 #define OPTIONS "8KLdel:nw" 127 #endif 128 while ((ch = getopt(argc - argoff, argv + argoff, OPTIONS)) != EOF) 129 switch(ch) { 130 case 'K': 131 #ifdef KERBEROS 132 use_kerberos = 0; 133 #endif 134 break; 135 case 'L': /* -8Lew are ignored to allow rlogin aliases */ 136 case 'e': 137 case 'w': 138 case '8': 139 break; 140 case 'd': 141 dflag = 1; 142 break; 143 case 'l': 144 user = optarg; 145 break; 146 #ifdef KERBEROS 147 case 'k': 148 dest_realm = dst_realm_buf; 149 strncpy(dest_realm, optarg, REALM_SZ); 150 break; 151 #endif 152 case 'n': 153 nflag = 1; 154 break; 155 #ifdef KERBEROS 156 #ifdef CRYPT 157 case 'x': 158 doencrypt = 1; 159 des_set_key(cred.session, schedule); 160 break; 161 #endif 162 #endif 163 case '?': 164 default: 165 usage(); 166 } 167 optind += argoff; 168 169 /* if haven't gotten a host yet, do so */ 170 if (!host && !(host = argv[optind++])) 171 usage(); 172 173 /* if no further arguments, must have been called as rlogin. */ 174 if (!argv[optind]) { 175 if (asrsh) 176 *argv = "rlogin"; 177 execv(_PATH_RLOGIN, argv); 178 (void)fprintf(stderr, "rsh: can't exec %s.\n", _PATH_RLOGIN); 179 exit(1); 180 } 181 182 argc -= optind; 183 argv += optind; 184 185 if (!(pw = getpwuid(uid = getuid()))) { 186 (void)fprintf(stderr, "rsh: unknown user id.\n"); 187 exit(1); 188 } 189 if (!user) 190 user = pw->pw_name; 191 192 #ifdef KERBEROS 193 #ifdef CRYPT 194 /* -x turns off -n */ 195 if (doencrypt) 196 nflag = 0; 197 #endif 198 #endif 199 200 args = copyargs(argv); 201 202 sp = NULL; 203 #ifdef KERBEROS 204 if (use_kerberos) { 205 sp = getservbyname((doencrypt ? "ekshell" : "kshell"), "tcp"); 206 if (sp == NULL) { 207 use_kerberos = 0; 208 warning("can't get entry for %s/tcp service", 209 doencrypt ? "ekshell" : "kshell"); 210 } 211 } 212 #endif 213 if (sp == NULL) 214 sp = getservbyname("shell", "tcp"); 215 if (sp == NULL) { 216 (void)fprintf(stderr, "rsh: shell/tcp: unknown service.\n"); 217 exit(1); 218 } 219 220 #ifdef KERBEROS 221 try_connect: 222 if (use_kerberos) { 223 rem = KSUCCESS; 224 errno = 0; 225 if (dest_realm == NULL) 226 dest_realm = krb_realmofhost(host); 227 228 #ifdef CRYPT 229 if (doencrypt) 230 rem = krcmd_mutual(&host, sp->s_port, user, args, 231 &rfd2, dest_realm, &cred, schedule); 232 else 233 #endif 234 rem = krcmd(&host, sp->s_port, user, args, &rfd2, 235 dest_realm); 236 if (rem < 0) { 237 use_kerberos = 0; 238 sp = getservbyname("shell", "tcp"); 239 if (sp == NULL) { 240 (void)fprintf(stderr, 241 "rsh: unknown service shell/tcp.\n"); 242 exit(1); 243 } 244 if (errno == ECONNREFUSED) 245 warning("remote host doesn't support Kerberos"); 246 if (errno == ENOENT) 247 warning("can't provide Kerberos auth data"); 248 goto try_connect; 249 } 250 } else { 251 if (doencrypt) { 252 (void)fprintf(stderr, 253 "rsh: the -x flag requires Kerberos authentication.\n"); 254 exit(1); 255 } 256 rem = rcmd(&host, sp->s_port, pw->pw_name, user, args, &rfd2); 257 } 258 #else 259 rem = rcmd(&host, sp->s_port, pw->pw_name, user, args, &rfd2); 260 #endif 261 262 if (rem < 0) 263 exit(1); 264 265 if (rfd2 < 0) { 266 (void)fprintf(stderr, "rsh: can't establish stderr.\n"); 267 exit(1); 268 } 269 if (dflag) { 270 if (setsockopt(rem, SOL_SOCKET, SO_DEBUG, &one, 271 sizeof(one)) < 0) 272 (void)fprintf(stderr, "rsh: setsockopt: %s.\n", 273 strerror(errno)); 274 if (setsockopt(rfd2, SOL_SOCKET, SO_DEBUG, &one, 275 sizeof(one)) < 0) 276 (void)fprintf(stderr, "rsh: setsockopt: %s.\n", 277 strerror(errno)); 278 } 279 280 (void)setuid(uid); 281 omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGTERM)); 282 if (signal(SIGINT, SIG_IGN) != SIG_IGN) 283 (void)signal(SIGINT, sendsig); 284 if (signal(SIGQUIT, SIG_IGN) != SIG_IGN) 285 (void)signal(SIGQUIT, sendsig); 286 if (signal(SIGTERM, SIG_IGN) != SIG_IGN) 287 (void)signal(SIGTERM, sendsig); 288 289 if (!nflag) { 290 pid = fork(); 291 if (pid < 0) { 292 (void)fprintf(stderr, 293 "rsh: fork: %s.\n", strerror(errno)); 294 exit(1); 295 } 296 } 297 298 #ifdef KERBEROS 299 #ifdef CRYPT 300 if (!doencrypt) 301 #endif 302 #endif 303 { 304 (void)ioctl(rfd2, FIONBIO, &one); 305 (void)ioctl(rem, FIONBIO, &one); 306 } 307 308 talk(nflag, omask, pid, rem); 309 310 if (!nflag) 311 (void)kill(pid, SIGKILL); 312 exit(0); 313 } 314 315 talk(nflag, omask, pid, rem) 316 int nflag, pid; 317 long omask; 318 register int rem; 319 { 320 register int cc, wc; 321 register char *bp; 322 int readfrom, ready, rembits; 323 char buf[BUFSIZ]; 324 325 if (!nflag && pid == 0) { 326 (void)close(rfd2); 327 328 reread: errno = 0; 329 if ((cc = read(0, buf, sizeof buf)) <= 0) 330 goto done; 331 bp = buf; 332 333 rewrite: rembits = 1 << rem; 334 if (select(16, 0, &rembits, 0, 0) < 0) { 335 if (errno != EINTR) { 336 (void)fprintf(stderr, 337 "rsh: select: %s.\n", strerror(errno)); 338 exit(1); 339 } 340 goto rewrite; 341 } 342 if ((rembits & (1 << rem)) == 0) 343 goto rewrite; 344 #ifdef KERBEROS 345 #ifdef CRYPT 346 if (doencrypt) 347 wc = des_write(rem, bp, cc); 348 else 349 #endif 350 #endif 351 wc = write(rem, bp, cc); 352 if (wc < 0) { 353 if (errno == EWOULDBLOCK) 354 goto rewrite; 355 goto done; 356 } 357 bp += wc; 358 cc -= wc; 359 if (cc == 0) 360 goto reread; 361 goto rewrite; 362 done: 363 (void)shutdown(rem, 1); 364 exit(0); 365 } 366 367 (void)sigsetmask(omask); 368 readfrom = (1 << rfd2) | (1 << rem); 369 do { 370 ready = readfrom; 371 if (select(16, &ready, 0, 0, 0) < 0) { 372 if (errno != EINTR) { 373 (void)fprintf(stderr, 374 "rsh: select: %s.\n", strerror(errno)); 375 exit(1); 376 } 377 continue; 378 } 379 if (ready & (1 << rfd2)) { 380 errno = 0; 381 #ifdef KERBEROS 382 #ifdef CRYPT 383 if (doencrypt) 384 cc = des_read(rfd2, buf, sizeof buf); 385 else 386 #endif 387 #endif 388 cc = read(rfd2, buf, sizeof buf); 389 if (cc <= 0) { 390 if (errno != EWOULDBLOCK) 391 readfrom &= ~(1 << rfd2); 392 } else 393 (void)write(2, buf, cc); 394 } 395 if (ready & (1 << rem)) { 396 errno = 0; 397 #ifdef KERBEROS 398 #ifdef CRYPT 399 if (doencrypt) 400 cc = des_read(rem, buf, sizeof buf); 401 else 402 #endif 403 #endif 404 cc = read(rem, buf, sizeof buf); 405 if (cc <= 0) { 406 if (errno != EWOULDBLOCK) 407 readfrom &= ~(1 << rem); 408 } else 409 (void)write(1, buf, cc); 410 } 411 } while (readfrom); 412 } 413 414 void 415 sendsig(signo) 416 char signo; 417 { 418 #ifdef KERBEROS 419 #ifdef CRYPT 420 if (doencrypt) 421 (void)des_write(rfd2, &signo, 1); 422 else 423 #endif 424 #endif 425 (void)write(rfd2, &signo, 1); 426 } 427 428 #ifdef KERBEROS 429 /* VARARGS */ 430 warning(va_alist) 431 va_dcl 432 { 433 va_list ap; 434 char *fmt; 435 436 (void)fprintf(stderr, "rsh: warning, using standard rsh: "); 437 va_start(ap); 438 fmt = va_arg(ap, char *); 439 vfprintf(stderr, fmt, ap); 440 va_end(ap); 441 (void)fprintf(stderr, ".\n"); 442 } 443 #endif 444 445 char * 446 copyargs(argv) 447 char **argv; 448 { 449 register int cc; 450 register char **ap, *p; 451 char *args, *malloc(); 452 453 cc = 0; 454 for (ap = argv; *ap; ++ap) 455 cc += strlen(*ap) + 1; 456 if (!(args = malloc((u_int)cc))) { 457 (void)fprintf(stderr, "rsh: %s.\n", strerror(ENOMEM)); 458 exit(1); 459 } 460 for (p = args, ap = argv; *ap; ++ap) { 461 (void)strcpy(p, *ap); 462 for (p = strcpy(p, *ap); *p; ++p); 463 if (ap[1]) 464 *p++ = ' '; 465 } 466 return(args); 467 } 468 469 usage() 470 { 471 (void)fprintf(stderr, 472 "usage: rsh [-nd%s]%s[-l login] host [command]\n", 473 #ifdef KERBEROS 474 #ifdef CRYPT 475 "x", " [-k realm] "); 476 #else 477 "", " [-k realm] "); 478 #endif 479 #else 480 "", " "); 481 #endif 482 exit(1); 483 } 484
Indexes created Tue Sep 23 14:10:03 GMT 2025