1 /* $OpenBSD: ssh-keyscan.c,v 1.85 2011/03/15 10:36:02 okan Exp $ */ 2 /* 3 * Copyright 1995, 1996 by David Mazieres <dm@lcs.mit.edu>. 4 * 5 * Modification and redistribution in source and binary forms is 6 * permitted provided that due credit is given to the author and the 7 * OpenBSD project by leaving this copyright notice intact. 8 */ 9 10 #include "includes.h" 11 12 #include "openbsd-compat/sys-queue.h" 13 #include <sys/resource.h> 14 #ifdef HAVE_SYS_TIME_H 15 # include <sys/time.h> 16 #endif 17 18 #include <netinet/in.h> 19 #include <arpa/inet.h> 20 21 #include <openssl/bn.h> 22 23 #include <netdb.h> 24 #include <errno.h> 25 #include <setjmp.h> 26 #include <stdarg.h> 27 #include <stdio.h> 28 #include <stdlib.h> 29 #include <signal.h> 30 #include <string.h> 31 #include <unistd.h> 32 33 #include "xmalloc.h" 34 #include "ssh.h" 35 #include "ssh1.h" 36 #include "buffer.h" 37 #include "key.h" 38 #include "cipher.h" 39 #include "kex.h" 40 #include "compat.h" 41 #include "myproposal.h" 42 #include "packet.h" 43 #include "dispatch.h" 44 #include "log.h" 45 #include "atomicio.h" 46 #include "misc.h" 47 #include "hostfile.h" 48 49 /* Flag indicating whether IPv4 or IPv6. This can be set on the command line. 50 Default value is AF_UNSPEC means both IPv4 and IPv6. */ 51 int IPv4or6 = AF_UNSPEC; 52 53 int ssh_port = SSH_DEFAULT_PORT; 54 55 #define KT_RSA1 1 56 #define KT_DSA 2 57 #define KT_RSA 4 58 #define KT_ECDSA 8 59 60 int get_keytypes = KT_RSA; /* Get only RSA keys by default */ 61 62 int hash_hosts = 0; /* Hash hostname on output */ 63 64 #define MAXMAXFD 256 65 66 /* The number of seconds after which to give up on a TCP connection */ 67 int timeout = 5; 68 69 int maxfd; 70 #define MAXCON (maxfd - 10) 71 72 extern char *__progname; 73 fd_set *read_wait; 74 size_t read_wait_nfdset; 75 int ncon; 76 int nonfatal_fatal = 0; 77 jmp_buf kexjmp; 78 Key *kexjmp_key; 79 80 /* 81 * Keep a connection structure for each file descriptor. The state 82 * associated with file descriptor n is held in fdcon[n]. 83 */ 84 typedef struct Connection { 85 u_char c_status; /* State of connection on this file desc. */ 86 #define CS_UNUSED 0 /* File descriptor unused */ 87 #define CS_CON 1 /* Waiting to connect/read greeting */ 88 #define CS_SIZE 2 /* Waiting to read initial packet size */ 89 #define CS_KEYS 3 /* Waiting to read public key packet */ 90 int c_fd; /* Quick lookup: c->c_fd == c - fdcon */ 91 int c_plen; /* Packet length field for ssh packet */ 92 int c_len; /* Total bytes which must be read. */ 93 int c_off; /* Length of data read so far. */ 94 int c_keytype; /* Only one of KT_RSA1, KT_DSA, or KT_RSA */ 95 char *c_namebase; /* Address to free for c_name and c_namelist */ 96 char *c_name; /* Hostname of connection for errors */ 97 char *c_namelist; /* Pointer to other possible addresses */ 98 char *c_output_name; /* Hostname of connection for output */ 99 char *c_data; /* Data read from this fd */ 100 Kex *c_kex; /* The key-exchange struct for ssh2 */ 101 struct timeval c_tv; /* Time at which connection gets aborted */ 102 TAILQ_ENTRY(Connection) c_link; /* List of connections in timeout order. */ 103 } con; 104 105 TAILQ_HEAD(conlist, Connection) tq; /* Timeout Queue */ 106 con *fdcon; 107 108 static int 109 fdlim_get(int hard) 110 { 111 #if defined(HAVE_GETRLIMIT) && defined(RLIMIT_NOFILE) 112 struct rlimit rlfd; 113 114 if (getrlimit(RLIMIT_NOFILE, &rlfd) < 0) 115 return (-1); 116 if ((hard ? rlfd.rlim_max : rlfd.rlim_cur) == RLIM_INFINITY) 117 return SSH_SYSFDMAX; 118 else 119 return hard ? rlfd.rlim_max : rlfd.rlim_cur; 120 #else 121 return SSH_SYSFDMAX; 122 #endif 123 } 124 125 static int 126 fdlim_set(int lim) 127 { 128 #if defined(HAVE_SETRLIMIT) && defined(RLIMIT_NOFILE) 129 struct rlimit rlfd; 130 #endif 131 132 if (lim <= 0) 133 return (-1); 134 #if defined(HAVE_SETRLIMIT) && defined(RLIMIT_NOFILE) 135 if (getrlimit(RLIMIT_NOFILE, &rlfd) < 0) 136 return (-1); 137 rlfd.rlim_cur = lim; 138 if (setrlimit(RLIMIT_NOFILE, &rlfd) < 0) 139 return (-1); 140 #elif defined (HAVE_SETDTABLESIZE) 141 setdtablesize(lim); 142 #endif 143 return (0); 144 } 145 146 /* 147 * This is an strsep function that returns a null field for adjacent 148 * separators. This is the same as the 4.4BSD strsep, but different from the 149 * one in the GNU libc. 150 */ 151 static char * 152 xstrsep(char **str, const char *delim) 153 { 154 char *s, *e; 155 156 if (!**str) 157 return (NULL); 158 159 s = *str; 160 e = s + strcspn(s, delim); 161 162 if (*e != '\0') 163 *e++ = '\0'; 164 *str = e; 165 166 return (s); 167 } 168 169 /* 170 * Get the next non-null token (like GNU strsep). Strsep() will return a 171 * null token for two adjacent separators, so we may have to loop. 172 */ 173 static char * 174 strnnsep(char **stringp, char *delim) 175 { 176 char *tok; 177 178 do { 179 tok = xstrsep(stringp, delim); 180 } while (tok && *tok == '\0'); 181 return (tok); 182 } 183 184 static Key * 185 keygrab_ssh1(con *c) 186 { 187 static Key *rsa; 188 static Buffer msg; 189 190 if (rsa == NULL) { 191 buffer_init(&msg); 192 rsa = key_new(KEY_RSA1); 193 } 194 buffer_append(&msg, c->c_data, c->c_plen); 195 buffer_consume(&msg, 8 - (c->c_plen & 7)); /* padding */ 196 if (buffer_get_char(&msg) != (int) SSH_SMSG_PUBLIC_KEY) { 197 error("%s: invalid packet type", c->c_name); 198 buffer_clear(&msg); 199 return NULL; 200 } 201 buffer_consume(&msg, 8); /* cookie */ 202 203 /* server key */ 204 (void) buffer_get_int(&msg); 205 buffer_get_bignum(&msg, rsa->rsa->e); 206 buffer_get_bignum(&msg, rsa->rsa->n); 207 208 /* host key */ 209 (void) buffer_get_int(&msg); 210 buffer_get_bignum(&msg, rsa->rsa->e); 211 buffer_get_bignum(&msg, rsa->rsa->n); 212 213 buffer_clear(&msg); 214 215 return (rsa); 216 } 217 218 static int 219 hostjump(Key *hostkey) 220 { 221 kexjmp_key = hostkey; 222 longjmp(kexjmp, 1); 223 } 224 225 static int 226 ssh2_capable(int remote_major, int remote_minor) 227 { 228 switch (remote_major) { 229 case 1: 230 if (remote_minor == 99) 231 return 1; 232 break; 233 case 2: 234 return 1; 235 default: 236 break; 237 } 238 return 0; 239 } 240 241 static Key * 242 keygrab_ssh2(con *c) 243 { 244 int j; 245 246 packet_set_connection(c->c_fd, c->c_fd); 247 enable_compat20(); 248 myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = c->c_keytype == KT_DSA? 249 "ssh-dss" : (c->c_keytype == KT_RSA ? "ssh-rsa" : 250 "ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521"); 251 c->c_kex = kex_setup(myproposal); 252 c->c_kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client; 253 c->c_kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client; 254 c->c_kex->kex[KEX_DH_GEX_SHA1] = kexgex_client; 255 c->c_kex->kex[KEX_DH_GEX_SHA256] = kexgex_client; 256 c->c_kex->kex[KEX_ECDH_SHA2] = kexecdh_client; 257 c->c_kex->verify_host_key = hostjump; 258 259 if (!(j = setjmp(kexjmp))) { 260 nonfatal_fatal = 1; 261 dispatch_run(DISPATCH_BLOCK, &c->c_kex->done, c->c_kex); 262 fprintf(stderr, "Impossible! dispatch_run() returned!\n"); 263 exit(1); 264 } 265 nonfatal_fatal = 0; 266 xfree(c->c_kex); 267 c->c_kex = NULL; 268 packet_close(); 269 270 return j < 0? NULL : kexjmp_key; 271 } 272 273 static void 274 keyprint(con *c, Key *key) 275 { 276 char *host = c->c_output_name ? c->c_output_name : c->c_name; 277 278 if (!key) 279 return; 280 if (hash_hosts && (host = host_hash(host, NULL, 0)) == NULL) 281 fatal("host_hash failed"); 282 283 fprintf(stdout, "%s ", host); 284 key_write(key, stdout); 285 fputs("\n", stdout); 286 } 287 288 static int 289 tcpconnect(char *host) 290 { 291 struct addrinfo hints, *ai, *aitop; 292 char strport[NI_MAXSERV]; 293 int gaierr, s = -1; 294 295 snprintf(strport, sizeof strport, "%d", ssh_port); 296 memset(&hints, 0, sizeof(hints)); 297 hints.ai_family = IPv4or6; 298 hints.ai_socktype = SOCK_STREAM; 299 if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) 300 fatal("getaddrinfo %s: %s", host, ssh_gai_strerror(gaierr)); 301 for (ai = aitop; ai; ai = ai->ai_next) { 302 s = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); 303 if (s < 0) { 304 error("socket: %s", strerror(errno)); 305 continue; 306 } 307 if (set_nonblock(s) == -1) 308 fatal("%s: set_nonblock(%d)", __func__, s); 309 if (connect(s, ai->ai_addr, ai->ai_addrlen) < 0 && 310 errno != EINPROGRESS) 311 error("connect (`%s'): %s", host, strerror(errno)); 312 else 313 break; 314 close(s); 315 s = -1; 316 } 317 freeaddrinfo(aitop); 318 return s; 319 } 320 321 static int 322 conalloc(char *iname, char *oname, int keytype) 323 { 324 char *namebase, *name, *namelist; 325 int s; 326 327 namebase = namelist = xstrdup(iname); 328 329 do { 330 name = xstrsep(&namelist, ","); 331 if (!name) { 332 xfree(namebase); 333 return (-1); 334 } 335 } while ((s = tcpconnect(name)) < 0); 336 337 if (s >= maxfd) 338 fatal("conalloc: fdno %d too high", s); 339 if (fdcon[s].c_status) 340 fatal("conalloc: attempt to reuse fdno %d", s); 341 342 fdcon[s].c_fd = s; 343 fdcon[s].c_status = CS_CON; 344 fdcon[s].c_namebase = namebase; 345 fdcon[s].c_name = name; 346 fdcon[s].c_namelist = namelist; 347 fdcon[s].c_output_name = xstrdup(oname); 348 fdcon[s].c_data = (char *) &fdcon[s].c_plen; 349 fdcon[s].c_len = 4; 350 fdcon[s].c_off = 0; 351 fdcon[s].c_keytype = keytype; 352 gettimeofday(&fdcon[s].c_tv, NULL); 353 fdcon[s].c_tv.tv_sec += timeout; 354 TAILQ_INSERT_TAIL(&tq, &fdcon[s], c_link); 355 FD_SET(s, read_wait); 356 ncon++; 357 return (s); 358 } 359 360 static void 361 confree(int s) 362 { 363 if (s >= maxfd || fdcon[s].c_status == CS_UNUSED) 364 fatal("confree: attempt to free bad fdno %d", s); 365 close(s); 366 xfree(fdcon[s].c_namebase); 367 xfree(fdcon[s].c_output_name); 368 if (fdcon[s].c_status == CS_KEYS) 369 xfree(fdcon[s].c_data); 370 fdcon[s].c_status = CS_UNUSED; 371 fdcon[s].c_keytype = 0; 372 TAILQ_REMOVE(&tq, &fdcon[s], c_link); 373 FD_CLR(s, read_wait); 374 ncon--; 375 } 376 377 static void 378 contouch(int s) 379 { 380 TAILQ_REMOVE(&tq, &fdcon[s], c_link); 381 gettimeofday(&fdcon[s].c_tv, NULL); 382 fdcon[s].c_tv.tv_sec += timeout; 383 TAILQ_INSERT_TAIL(&tq, &fdcon[s], c_link); 384 } 385 386 static int 387 conrecycle(int s) 388 { 389 con *c = &fdcon[s]; 390 int ret; 391 392 ret = conalloc(c->c_namelist, c->c_output_name, c->c_keytype); 393 confree(s); 394 return (ret); 395 } 396 397 static void 398 congreet(int s) 399 { 400 int n = 0, remote_major = 0, remote_minor = 0; 401 char buf[256], *cp; 402 char remote_version[sizeof buf]; 403 size_t bufsiz; 404 con *c = &fdcon[s]; 405 406 for (;;) { 407 memset(buf, '\0', sizeof(buf)); 408 bufsiz = sizeof(buf); 409 cp = buf; 410 while (bufsiz-- && 411 (n = atomicio(read, s, cp, 1)) == 1 && *cp != '\n') { 412 if (*cp == '\r') 413 *cp = '\n'; 414 cp++; 415 } 416 if (n != 1 || strncmp(buf, "SSH-", 4) == 0) 417 break; 418 } 419 if (n == 0) { 420 switch (errno) { 421 case EPIPE: 422 error("%s: Connection closed by remote host", c->c_name); 423 break; 424 case ECONNREFUSED: 425 break; 426 default: 427 error("read (%s): %s", c->c_name, strerror(errno)); 428 break; 429 } 430 conrecycle(s); 431 return; 432 } 433 if (*cp != '\n' && *cp != '\r') { 434 error("%s: bad greeting", c->c_name); 435 confree(s); 436 return; 437 } 438 *cp = '\0'; 439 if (sscanf(buf, "SSH-%d.%d-%[^\n]\n", 440 &remote_major, &remote_minor, remote_version) == 3) 441 compat_datafellows(remote_version); 442 else 443 datafellows = 0; 444 if (c->c_keytype != KT_RSA1) { 445 if (!ssh2_capable(remote_major, remote_minor)) { 446 debug("%s doesn't support ssh2", c->c_name); 447 confree(s); 448 return; 449 } 450 } else if (remote_major != 1) { 451 debug("%s doesn't support ssh1", c->c_name); 452 confree(s); 453 return; 454 } 455 fprintf(stderr, "# %s %s\n", c->c_name, chop(buf)); 456 n = snprintf(buf, sizeof buf, "SSH-%d.%d-OpenSSH-keyscan\r\n", 457 c->c_keytype == KT_RSA1? PROTOCOL_MAJOR_1 : PROTOCOL_MAJOR_2, 458 c->c_keytype == KT_RSA1? PROTOCOL_MINOR_1 : PROTOCOL_MINOR_2); 459 if (n < 0 || (size_t)n >= sizeof(buf)) { 460 error("snprintf: buffer too small"); 461 confree(s); 462 return; 463 } 464 if (atomicio(vwrite, s, buf, n) != (size_t)n) { 465 error("write (%s): %s", c->c_name, strerror(errno)); 466 confree(s); 467 return; 468 } 469 if (c->c_keytype != KT_RSA1) { 470 keyprint(c, keygrab_ssh2(c)); 471 confree(s); 472 return; 473 } 474 c->c_status = CS_SIZE; 475 contouch(s); 476 } 477 478 static void 479 conread(int s) 480 { 481 con *c = &fdcon[s]; 482 size_t n; 483 484 if (c->c_status == CS_CON) { 485 congreet(s); 486 return; 487 } 488 n = atomicio(read, s, c->c_data + c->c_off, c->c_len - c->c_off); 489 if (n == 0) { 490 error("read (%s): %s", c->c_name, strerror(errno)); 491 confree(s); 492 return; 493 } 494 c->c_off += n; 495 496 if (c->c_off == c->c_len) 497 switch (c->c_status) { 498 case CS_SIZE: 499 c->c_plen = htonl(c->c_plen); 500 c->c_len = c->c_plen + 8 - (c->c_plen & 7); 501 c->c_off = 0; 502 c->c_data = xmalloc(c->c_len); 503 c->c_status = CS_KEYS; 504 break; 505 case CS_KEYS: 506 keyprint(c, keygrab_ssh1(c)); 507 confree(s); 508 return; 509 default: 510 fatal("conread: invalid status %d", c->c_status); 511 break; 512 } 513 514 contouch(s); 515 } 516 517 static void 518 conloop(void) 519 { 520 struct timeval seltime, now; 521 fd_set *r, *e; 522 con *c; 523 int i; 524 525 gettimeofday(&now, NULL); 526 c = TAILQ_FIRST(&tq); 527 528 if (c && (c->c_tv.tv_sec > now.tv_sec || 529 (c->c_tv.tv_sec == now.tv_sec && c->c_tv.tv_usec > now.tv_usec))) { 530 seltime = c->c_tv; 531 seltime.tv_sec -= now.tv_sec; 532 seltime.tv_usec -= now.tv_usec; 533 if (seltime.tv_usec < 0) { 534 seltime.tv_usec += 1000000; 535 seltime.tv_sec--; 536 } 537 } else 538 timerclear(&seltime); 539 540 r = xcalloc(read_wait_nfdset, sizeof(fd_mask)); 541 e = xcalloc(read_wait_nfdset, sizeof(fd_mask)); 542 memcpy(r, read_wait, read_wait_nfdset * sizeof(fd_mask)); 543 memcpy(e, read_wait, read_wait_nfdset * sizeof(fd_mask)); 544 545 while (select(maxfd, r, NULL, e, &seltime) == -1 && 546 (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK)) 547 ; 548 549 for (i = 0; i < maxfd; i++) { 550 if (FD_ISSET(i, e)) { 551 error("%s: exception!", fdcon[i].c_name); 552 confree(i); 553 } else if (FD_ISSET(i, r)) 554 conread(i); 555 } 556 xfree(r); 557 xfree(e); 558 559 c = TAILQ_FIRST(&tq); 560 while (c && (c->c_tv.tv_sec < now.tv_sec || 561 (c->c_tv.tv_sec == now.tv_sec && c->c_tv.tv_usec < now.tv_usec))) { 562 int s = c->c_fd; 563 564 c = TAILQ_NEXT(c, c_link); 565 conrecycle(s); 566 } 567 } 568 569 static void 570 do_host(char *host) 571 { 572 char *name = strnnsep(&host, " \t\n"); 573 int j; 574 575 if (name == NULL) 576 return; 577 for (j = KT_RSA1; j <= KT_ECDSA; j *= 2) { 578 if (get_keytypes & j) { 579 while (ncon >= MAXCON) 580 conloop(); 581 conalloc(name, *host ? host : name, j); 582 } 583 } 584 } 585 586 void 587 fatal(const char *fmt,...) 588 { 589 va_list args; 590 591 va_start(args, fmt); 592 do_log(SYSLOG_LEVEL_FATAL, fmt, args); 593 va_end(args); 594 if (nonfatal_fatal) 595 longjmp(kexjmp, -1); 596 else 597 exit(255); 598 } 599 600 static void 601 usage(void) 602 { 603 fprintf(stderr, 604 "usage: %s [-46Hv] [-f file] [-p port] [-T timeout] [-t type]\n" 605 "\t\t [host | addrlist namelist] ...\n", 606 __progname); 607 exit(1); 608 } 609 610 int 611 main(int argc, char **argv) 612 { 613 int debug_flag = 0, log_level = SYSLOG_LEVEL_INFO; 614 int opt, fopt_count = 0, j; 615 char *tname, *cp, line[NI_MAXHOST]; 616 FILE *fp; 617 u_long linenum; 618 619 extern int optind; 620 extern char *optarg; 621 622 __progname = ssh_get_progname(argv[0]); 623 seed_rng(); 624 TAILQ_INIT(&tq); 625 626 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 627 sanitise_stdfd(); 628 629 if (argc <= 1) 630 usage(); 631 632 while ((opt = getopt(argc, argv, "Hv46p:T:t:f:")) != -1) { 633 switch (opt) { 634 case 'H': 635 hash_hosts = 1; 636 break; 637 case 'p': 638 ssh_port = a2port(optarg); 639 if (ssh_port <= 0) { 640 fprintf(stderr, "Bad port '%s'\n", optarg); 641 exit(1); 642 } 643 break; 644 case 'T': 645 timeout = convtime(optarg); 646 if (timeout == -1 || timeout == 0) { 647 fprintf(stderr, "Bad timeout '%s'\n", optarg); 648 usage(); 649 } 650 break; 651 case 'v': 652 if (!debug_flag) { 653 debug_flag = 1; 654 log_level = SYSLOG_LEVEL_DEBUG1; 655 } 656 else if (log_level < SYSLOG_LEVEL_DEBUG3) 657 log_level++; 658 else 659 fatal("Too high debugging level."); 660 break; 661 case 'f': 662 if (strcmp(optarg, "-") == 0) 663 optarg = NULL; 664 argv[fopt_count++] = optarg; 665 break; 666 case 't': 667 get_keytypes = 0; 668 tname = strtok(optarg, ","); 669 while (tname) { 670 int type = key_type_from_name(tname); 671 switch (type) { 672 case KEY_RSA1: 673 get_keytypes |= KT_RSA1; 674 break; 675 case KEY_DSA: 676 get_keytypes |= KT_DSA; 677 break; 678 case KEY_ECDSA: 679 get_keytypes |= KT_ECDSA; 680 break; 681 case KEY_RSA: 682 get_keytypes |= KT_RSA; 683 break; 684 case KEY_UNSPEC: 685 fatal("unknown key type %s", tname); 686 } 687 tname = strtok(NULL, ","); 688 } 689 break; 690 case '4': 691 IPv4or6 = AF_INET; 692 break; 693 case '6': 694 IPv4or6 = AF_INET6; 695 break; 696 case '?': 697 default: 698 usage(); 699 } 700 } 701 if (optind == argc && !fopt_count) 702 usage(); 703 704 log_init("ssh-keyscan", log_level, SYSLOG_FACILITY_USER, 1); 705 706 maxfd = fdlim_get(1); 707 if (maxfd < 0) 708 fatal("%s: fdlim_get: bad value", __progname); 709 if (maxfd > MAXMAXFD) 710 maxfd = MAXMAXFD; 711 if (MAXCON <= 0) 712 fatal("%s: not enough file descriptors", __progname); 713 if (maxfd > fdlim_get(0)) 714 fdlim_set(maxfd); 715 fdcon = xcalloc(maxfd, sizeof(con)); 716 717 read_wait_nfdset = howmany(maxfd, NFDBITS); 718 read_wait = xcalloc(read_wait_nfdset, sizeof(fd_mask)); 719 720 for (j = 0; j < fopt_count; j++) { 721 if (argv[j] == NULL) 722 fp = stdin; 723 else if ((fp = fopen(argv[j], "r")) == NULL) 724 fatal("%s: %s: %s", __progname, argv[j], 725 strerror(errno)); 726 linenum = 0; 727 728 while (read_keyfile_line(fp, 729 argv[j] == NULL ? "(stdin)" : argv[j], line, sizeof(line), 730 &linenum) != -1) { 731 /* Chomp off trailing whitespace and comments */ 732 if ((cp = strchr(line, '#')) == NULL) 733 cp = line + strlen(line) - 1; 734 while (cp >= line) { 735 if (*cp == ' ' || *cp == '\t' || 736 *cp == '\n' || *cp == '#') 737 *cp-- = '\0'; 738 else 739 break; 740 } 741 742 /* Skip empty lines */ 743 if (*line == '\0') 744 continue; 745 746 do_host(line); 747 } 748 749 if (ferror(fp)) 750 fatal("%s: %s: %s", __progname, argv[j], 751 strerror(errno)); 752 753 fclose(fp); 754 } 755 756 while (optind < argc) 757 do_host(argv[optind++]); 758 759 while (ncon > 0) 760 conloop(); 761 762 return (0); 763 } 764