crypto/external/bsd/openssh/dist/ssh-keyscan.c

   1 /*      $NetBSD$        */
   2 /* $OpenBSD: ssh-keyscan.c,v 1.78 2009/01/22 10:02:34 djm Exp $ */
   3 /*
   4  * Copyright 1995, 1996 by David Mazieres <dm@lcs.mit.edu>.
   5  *
   6  * Modification and redistribution in source and binary forms is
   7  * permitted provided that due credit is given to the author and the
   8  * OpenBSD project by leaving this copyright notice intact.
   9  */
  10
  11 #include "includes.h"
  12 __RCSID("$NetBSD: ssh-keyscan.c,v 1.27 2009/02/16 20:53:55 christos Exp $");
  13 #include <sys/types.h>
  14 #include <sys/socket.h>
  15 #include <sys/queue.h>
  16 #include <sys/time.h>
  17 #include <sys/resource.h>
  18
  19 #include <openssl/bn.h>
  20
  21 #include <errno.h>
  22 #include <netdb.h>
  23 #include <setjmp.h>
  24 #include <stdarg.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <signal.h>
  28 #include <string.h>
  29 #include <unistd.h>
  30
  31 #include "xmalloc.h"
  32 #include "ssh.h"
  33 #include "ssh1.h"
  34 #include "buffer.h"
  35 #include "key.h"
  36 #include "cipher.h"
  37 #include "kex.h"
  38 #include "compat.h"
  39 #include "myproposal.h"
  40 #include "packet.h"
  41 #include "dispatch.h"
  42 #include "log.h"
  43 #include "atomicio.h"
  44 #include "misc.h"
  45 #include "hostfile.h"
  46
  47 /* Flag indicating whether IPv4 or IPv6.  This can be set on the command line.
  48    Default value is AF_UNSPEC means both IPv4 and IPv6. */
  49 int IPv4or6 = AF_UNSPEC;
  50
  51 int ssh_port = SSH_DEFAULT_PORT;
  52
  53 #define KT_RSA1 1
  54 #define KT_DSA  2
  55 #define KT_RSA  4
  56
  57 int get_keytypes = KT_RSA;      /* Get only RSA keys by default */
  58
  59 int hash_hosts = 0;             /* Hash hostname on output */
  60
  61 #define MAXMAXFD 256
  62
  63 /* The number of seconds after which to give up on a TCP connection */
  64 int timeout = 5;
  65
  66 int maxfd;
  67 #define MAXCON (maxfd - 10)
  68
  69 extern char *__progname;
  70 fd_set *read_wait;
  71 size_t read_wait_nfdset;
  72 int ncon;
  73 int nonfatal_fatal = 0;
  74 jmp_buf kexjmp;
  75 Key *kexjmp_key;
  76
  77 /*
  78  * Keep a connection structure for each file descriptor.  The state
  79  * associated with file descriptor n is held in fdcon[n].
  80  */
  81 typedef struct Connection {
  82         u_char c_status;        /* State of connection on this file desc. */
  83 #define CS_UNUSED 0             /* File descriptor unused */
  84 #define CS_CON 1                /* Waiting to connect/read greeting */
  85 #define CS_SIZE 2               /* Waiting to read initial packet size */
  86 #define CS_KEYS 3               /* Waiting to read public key packet */
  87         int c_fd;               /* Quick lookup: c->c_fd == c - fdcon */
  88         int c_plen;             /* Packet length field for ssh packet */
  89         int c_len;              /* Total bytes which must be read. */
  90         int c_off;              /* Length of data read so far. */
  91         int c_keytype;          /* Only one of KT_RSA1, KT_DSA, or KT_RSA */
  92         char *c_namebase;       /* Address to free for c_name and c_namelist */
  93         char *c_name;           /* Hostname of connection for errors */
  94         char *c_namelist;       /* Pointer to other possible addresses */
  95         char *c_output_name;    /* Hostname of connection for output */
  96         char *c_data;           /* Data read from this fd */
  97         Kex *c_kex;             /* The key-exchange struct for ssh2 */
  98         struct timeval c_tv;    /* Time at which connection gets aborted */
  99         TAILQ_ENTRY(Connection) c_link; /* List of connections in timeout order. */
 100 } con;
 101
 102 TAILQ_HEAD(conlist, Connection) tq;     /* Timeout Queue */
 103 con *fdcon;
 104
 105 /*
 106  *  This is just a wrapper around fgets() to make it usable.
 107  */
 108
 109 /* Stress-test.  Increase this later. */
 110 #define LINEBUF_SIZE 16
 111
 112 typedef struct {
 113         char *buf;
 114         u_int size;
 115         int lineno;
 116         const char *filename;
 117         FILE *stream;
 118         void (*errfun) (const char *,...);
 119 } Linebuf;
 120
 121 static Linebuf *
 122 Linebuf_alloc(const char *filename, void (*errfun) (const char *,...))
 123 {
 124         Linebuf *lb;
 125
 126         if (!(lb = malloc(sizeof(*lb)))) {
 127                 if (errfun)
 128                         (*errfun) ("linebuf (%s): malloc failed\n",
 129                             filename ? filename : "(stdin)");
 130                 return (NULL);
 131         }
 132         if (filename) {
 133                 lb->filename = filename;
 134                 if (!(lb->stream = fopen(filename, "r"))) {
 135                         xfree(lb);
 136                         if (errfun)
 137                                 (*errfun) ("%s: %s\n", filename, strerror(errno));
 138                         return (NULL);
 139                 }
 140         } else {
 141                 lb->filename = "(stdin)";
 142                 lb->stream = stdin;
 143         }
 144
 145         if (!(lb->buf = malloc((lb->size = LINEBUF_SIZE)))) {
 146                 if (errfun)
 147                         (*errfun) ("linebuf (%s): malloc failed\n", lb->filename);
 148                 xfree(lb);
 149                 return (NULL);
 150         }
 151         lb->errfun = errfun;
 152         lb->lineno = 0;
 153         return (lb);
 154 }
 155
 156 static void
 157 Linebuf_free(Linebuf * lb)
 158 {
 159         fclose(lb->stream);
 160         xfree(lb->buf);
 161         xfree(lb);
 162 }
 163
 164 #if 0
 165 static void
 166 Linebuf_restart(Linebuf * lb)
 167 {
 168         clearerr(lb->stream);
 169         rewind(lb->stream);
 170         lb->lineno = 0;
 171 }
 172
 173 static int
 174 Linebuf_lineno(Linebuf * lb)
 175 {
 176         return (lb->lineno);
 177 }
 178 #endif
 179
 180 static char *
 181 Linebuf_getline(Linebuf * lb)
 182 {
 183         size_t n = 0;
 184         void *p;
 185
 186         lb->lineno++;
 187         for (;;) {
 188                 /* Read a line */
 189                 if (!fgets(&lb->buf[n], lb->size - n, lb->stream)) {
 190                         if (ferror(lb->stream) && lb->errfun)
 191                                 (*lb->errfun)("%s: %s\n", lb->filename,
 192                                     strerror(errno));
 193                         return (NULL);
 194                 }
 195                 n = strlen(lb->buf);
 196
 197                 /* Return it or an error if it fits */
 198                 if (n > 0 && lb->buf[n - 1] == '\n') {
 199                         lb->buf[n - 1] = '\0';
 200                         return (lb->buf);
 201                 }
 202                 if (n != lb->size - 1) {
 203                         if (lb->errfun)
 204                                 (*lb->errfun)("%s: skipping incomplete last line\n",
 205                                     lb->filename);
 206                         return (NULL);
 207                 }
 208                 /* Double the buffer if we need more space */
 209                 lb->size *= 2;
 210                 if ((p = realloc(lb->buf, lb->size)) == NULL) {
 211                         lb->size /= 2;
 212                         if (lb->errfun)
 213                                 (*lb->errfun)("linebuf (%s): realloc failed\n",
 214                                     lb->filename);
 215                         return (NULL);
 216                 }
 217                 lb->buf = p;
 218         }
 219 }
 220
 221 static int
 222 fdlim_get(int hard)
 223 {
 224         struct rlimit rlfd;
 225
 226         if (getrlimit(RLIMIT_NOFILE, &rlfd) < 0)
 227                 return (-1);
 228         if ((hard ? rlfd.rlim_max : rlfd.rlim_cur) == RLIM_INFINITY)
 229                 return sysconf(_SC_OPEN_MAX);
 230         else
 231                 return hard ? rlfd.rlim_max : rlfd.rlim_cur;
 232 }
 233
 234 static int
 235 fdlim_set(int lim)
 236 {
 237         struct rlimit rlfd;
 238
 239         if (lim <= 0)
 240                 return (-1);
 241         if (getrlimit(RLIMIT_NOFILE, &rlfd) < 0)
 242                 return (-1);
 243         rlfd.rlim_cur = lim;
 244         if (setrlimit(RLIMIT_NOFILE, &rlfd) < 0)
 245                 return (-1);
 246         return (0);
 247 }
 248
 249 /*
 250  * This is an strsep function that returns a null field for adjacent
 251  * separators.  This is the same as the 4.4BSD strsep, but different from the
 252  * one in the GNU libc.
 253  */
 254 static char *
 255 xstrsep(char **str, const char *delim)
 256 {
 257         char *s, *e;
 258
 259         if (!**str)
 260                 return (NULL);
 261
 262         s = *str;
 263         e = s + strcspn(s, delim);
 264
 265         if (*e != '\0')
 266                 *e++ = '\0';
 267         *str = e;
 268
 269         return (s);
 270 }
 271
 272 /*
 273  * Get the next non-null token (like GNU strsep).  Strsep() will return a
 274  * null token for two adjacent separators, so we may have to loop.
 275  */
 276 static char *
 277 strnnsep(char **stringp, char *delim)
 278 {
 279         char *tok;
 280
 281         do {
 282                 tok = xstrsep(stringp, delim);
 283         } while (tok && *tok == '\0');
 284         return (tok);
 285 }
 286
 287 static Key *
 288 keygrab_ssh1(con *c)
 289 {
 290         static Key *rsa;
 291         static Buffer msg;
 292
 293         if (rsa == NULL) {
 294                 buffer_init(&msg);
 295                 rsa = key_new(KEY_RSA1);
 296         }
 297         buffer_append(&msg, c->c_data, c->c_plen);
 298         buffer_consume(&msg, 8 - (c->c_plen & 7));      /* padding */
 299         if (buffer_get_char(&msg) != (int) SSH_SMSG_PUBLIC_KEY) {
 300                 error("%s: invalid packet type", c->c_name);
 301                 buffer_clear(&msg);
 302                 return NULL;
 303         }
 304         buffer_consume(&msg, 8);                /* cookie */
 305
 306         /* server key */
 307         (void) buffer_get_int(&msg);
 308         buffer_get_bignum(&msg, rsa->rsa->e);
 309         buffer_get_bignum(&msg, rsa->rsa->n);
 310
 311         /* host key */
 312         (void) buffer_get_int(&msg);
 313         buffer_get_bignum(&msg, rsa->rsa->e);
 314         buffer_get_bignum(&msg, rsa->rsa->n);
 315
 316         buffer_clear(&msg);
 317
 318         return (rsa);
 319 }
 320
 321 static int
 322 hostjump(Key *hostkey)
 323 {
 324         kexjmp_key = hostkey;
 325         longjmp(kexjmp, 1);
 326 }
 327
 328 static int
 329 ssh2_capable(int remote_major, int remote_minor)
 330 {
 331         switch (remote_major) {
 332         case 1:
 333                 if (remote_minor == 99)
 334                         return 1;
 335                 break;
 336         case 2:
 337                 return 1;
 338         default:
 339                 break;
 340         }
 341         return 0;
 342 }
 343
 344 static Key *
 345 keygrab_ssh2(con *c)
 346 {
 347         int j;
 348
 349         packet_set_connection(c->c_fd, c->c_fd);
 350         enable_compat20();
 351         myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = c->c_keytype == KT_DSA?
 352             "ssh-dss": "ssh-rsa";
 353         c->c_kex = kex_setup(myproposal);
 354         c->c_kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
 355         c->c_kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
 356         c->c_kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
 357         c->c_kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
 358         c->c_kex->verify_host_key = hostjump;
 359
 360         if (!(j = setjmp(kexjmp))) {
 361                 nonfatal_fatal = 1;
 362                 dispatch_run(DISPATCH_BLOCK, &c->c_kex->done, c->c_kex);
 363                 fprintf(stderr, "Impossible! dispatch_run() returned!\n");
 364                 exit(1);
 365         }
 366         nonfatal_fatal = 0;
 367         xfree(c->c_kex);
 368         c->c_kex = NULL;
 369         packet_close();
 370
 371         return j < 0? NULL : kexjmp_key;
 372 }
 373
 374 static void
 375 keyprint(con *c, Key *key)
 376 {
 377         char *host = c->c_output_name ? c->c_output_name : c->c_name;
 378
 379         if (!key)
 380                 return;
 381         if (hash_hosts && (host = host_hash(host, NULL, 0)) == NULL)
 382                 fatal("host_hash failed");
 383
 384         fprintf(stdout, "%s ", host);
 385         key_write(key, stdout);
 386         fputs("\n", stdout);
 387 }
 388
 389 static int
 390 tcpconnect(char *host)
 391 {
 392         struct addrinfo hints, *ai, *aitop;
 393         char strport[NI_MAXSERV];
 394         int gaierr, s = -1;
 395
 396         snprintf(strport, sizeof strport, "%d", ssh_port);
 397         memset(&hints, 0, sizeof(hints));
 398         hints.ai_family = IPv4or6;
 399         hints.ai_socktype = SOCK_STREAM;
 400         if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0)
 401                 fatal("getaddrinfo %s: %s", host, ssh_gai_strerror(gaierr));
 402         for (ai = aitop; ai; ai = ai->ai_next) {
 403                 s = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
 404                 if (s < 0) {
 405                         error("socket: %s", strerror(errno));
 406                         continue;
 407                 }
 408                 if (set_nonblock(s) == -1)
 409                         fatal("%s: set_nonblock(%d)", __func__, s);
 410                 if (connect(s, ai->ai_addr, ai->ai_addrlen) < 0 &&
 411                     errno != EINPROGRESS)
 412                         error("connect (`%s'): %s", host, strerror(errno));
 413                 else
 414                         break;
 415                 close(s);
 416                 s = -1;
 417         }
 418         freeaddrinfo(aitop);
 419         return s;
 420 }
 421
 422 static int
 423 conalloc(char *iname, char *oname, int keytype)
 424 {
 425         char *namebase, *name, *namelist;
 426         int s;
 427
 428         namebase = namelist = xstrdup(iname);
 429
 430         do {
 431                 name = xstrsep(&namelist, ",");
 432                 if (!name) {
 433                         xfree(namebase);
 434                         return (-1);
 435                 }
 436         } while ((s = tcpconnect(name)) < 0);
 437
 438         if (s >= maxfd)
 439                 fatal("conalloc: fdno %d too high", s);
 440         if (fdcon[s].c_status)
 441                 fatal("conalloc: attempt to reuse fdno %d", s);
 442
 443         fdcon[s].c_fd = s;
 444         fdcon[s].c_status = CS_CON;
 445         fdcon[s].c_namebase = namebase;
 446         fdcon[s].c_name = name;
 447         fdcon[s].c_namelist = namelist;
 448         fdcon[s].c_output_name = xstrdup(oname);
 449         fdcon[s].c_data = (char *) &fdcon[s].c_plen;
 450         fdcon[s].c_len = 4;
 451         fdcon[s].c_off = 0;
 452         fdcon[s].c_keytype = keytype;
 453         gettimeofday(&fdcon[s].c_tv, NULL);
 454         fdcon[s].c_tv.tv_sec += timeout;
 455         TAILQ_INSERT_TAIL(&tq, &fdcon[s], c_link);
 456         FD_SET(s, read_wait);
 457         ncon++;
 458         return (s);
 459 }
 460
 461 static void
 462 confree(int s)
 463 {
 464         if (s >= maxfd || fdcon[s].c_status == CS_UNUSED)
 465                 fatal("confree: attempt to free bad fdno %d", s);
 466         close(s);
 467         xfree(fdcon[s].c_namebase);
 468         xfree(fdcon[s].c_output_name);
 469         if (fdcon[s].c_status == CS_KEYS)
 470                 xfree(fdcon[s].c_data);
 471         fdcon[s].c_status = CS_UNUSED;
 472         fdcon[s].c_keytype = 0;
 473         TAILQ_REMOVE(&tq, &fdcon[s], c_link);
 474         FD_CLR(s, read_wait);
 475         ncon--;
 476 }
 477
 478 static void
 479 contouch(int s)
 480 {
 481         TAILQ_REMOVE(&tq, &fdcon[s], c_link);
 482         gettimeofday(&fdcon[s].c_tv, NULL);
 483         fdcon[s].c_tv.tv_sec += timeout;
 484         TAILQ_INSERT_TAIL(&tq, &fdcon[s], c_link);
 485 }
 486
 487 static int
 488 conrecycle(int s)
 489 {
 490         con *c = &fdcon[s];
 491         int ret;
 492
 493         ret = conalloc(c->c_namelist, c->c_output_name, c->c_keytype);
 494         confree(s);
 495         return (ret);
 496 }
 497
 498 static void
 499 congreet(int s)
 500 {
 501         int n = 0, remote_major = 0, remote_minor = 0;
 502         char buf[256], *cp;
 503         char remote_version[sizeof buf];
 504         size_t bufsiz;
 505         con *c = &fdcon[s];
 506
 507         for (;;) {
 508                 memset(buf, '\0', sizeof(buf));
 509                 bufsiz = sizeof(buf);
 510                 cp = buf;
 511                 while (bufsiz-- &&
 512                     (n = atomicio(read, s, cp, 1)) == 1 && *cp != '\n') {
 513                         if (*cp == '\r')
 514                                 *cp = '\n';
 515                         cp++;
 516                 }
 517                 if (n != 1 || strncmp(buf, "SSH-", 4) == 0)
 518                         break;
 519         }
 520         if (n == 0) {
 521                 switch (errno) {
 522                 case EPIPE:
 523                         error("%s: Connection closed by remote host", c->c_name);
 524                         break;
 525                 case ECONNREFUSED:
 526                         break;
 527                 default:
 528                         error("read (%s): %s", c->c_name, strerror(errno));
 529                         break;
 530                 }
 531                 conrecycle(s);
 532                 return;
 533         }
 534         if (*cp != '\n' && *cp != '\r') {
 535                 error("%s: bad greeting", c->c_name);
 536                 confree(s);
 537                 return;
 538         }
 539         *cp = '\0';
 540         if (sscanf(buf, "SSH-%d.%d-%[^\n]\n",
 541             &remote_major, &remote_minor, remote_version) == 3)
 542                 compat_datafellows(remote_version);
 543         else
 544                 datafellows = 0;
 545         if (c->c_keytype != KT_RSA1) {
 546                 if (!ssh2_capable(remote_major, remote_minor)) {
 547                         debug("%s doesn't support ssh2", c->c_name);
 548                         confree(s);
 549                         return;
 550                 }
 551         } else if (remote_major != 1) {
 552                 debug("%s doesn't support ssh1", c->c_name);
 553                 confree(s);
 554                 return;
 555         }
 556         fprintf(stderr, "# %s %s\n", c->c_name, chop(buf));
 557         n = snprintf(buf, sizeof buf, "SSH-%d.%d-OpenSSH-keyscan\r\n",
 558             c->c_keytype == KT_RSA1? PROTOCOL_MAJOR_1 : PROTOCOL_MAJOR_2,
 559             c->c_keytype == KT_RSA1? PROTOCOL_MINOR_1 : PROTOCOL_MINOR_2);
 560         if (n < 0 || (size_t)n >= sizeof(buf)) {
 561                 error("snprintf: buffer too small");
 562                 confree(s);
 563                 return;
 564         }
 565         if (atomicio(vwrite, s, buf, n) != (size_t)n) {
 566                 error("write (%s): %s", c->c_name, strerror(errno));
 567                 confree(s);
 568                 return;
 569         }
 570         if (c->c_keytype != KT_RSA1) {
 571                 keyprint(c, keygrab_ssh2(c));
 572                 confree(s);
 573                 return;
 574         }
 575         c->c_status = CS_SIZE;
 576         contouch(s);
 577 }
 578
 579 static void
 580 conread(int s)
 581 {
 582         con *c = &fdcon[s];
 583         size_t n;
 584
 585         if (c->c_status == CS_CON) {
 586                 congreet(s);
 587                 return;
 588         }
 589         n = atomicio(read, s, c->c_data + c->c_off, c->c_len - c->c_off);
 590         if (n == 0) {
 591                 error("read (%s): %s", c->c_name, strerror(errno));
 592                 confree(s);
 593                 return;
 594         }
 595         c->c_off += n;
 596
 597         if (c->c_off == c->c_len)
 598                 switch (c->c_status) {
 599                 case CS_SIZE:
 600                         c->c_plen = htonl(c->c_plen);
 601                         c->c_len = c->c_plen + 8 - (c->c_plen & 7);
 602                         c->c_off = 0;
 603                         c->c_data = xmalloc(c->c_len);
 604                         c->c_status = CS_KEYS;
 605                         break;
 606                 case CS_KEYS:
 607                         keyprint(c, keygrab_ssh1(c));
 608                         confree(s);
 609                         return;
 610                 default:
 611                         fatal("conread: invalid status %d", c->c_status);
 612                         break;
 613                 }
 614
 615         contouch(s);
 616 }
 617
 618 static void
 619 conloop(void)
 620 {
 621         struct timeval seltime, now;
 622         fd_set *r, *e;
 623         con *c;
 624         int i;
 625
 626         gettimeofday(&now, NULL);
 627         c = TAILQ_FIRST(&tq);
 628
 629         if (c && (c->c_tv.tv_sec > now.tv_sec ||
 630             (c->c_tv.tv_sec == now.tv_sec && c->c_tv.tv_usec > now.tv_usec))) {
 631                 seltime = c->c_tv;
 632                 seltime.tv_sec -= now.tv_sec;
 633                 seltime.tv_usec -= now.tv_usec;
 634                 if (seltime.tv_usec < 0) {
 635                         seltime.tv_usec += 1000000;
 636                         seltime.tv_sec--;
 637                 }
 638         } else
 639                 seltime.tv_sec = seltime.tv_usec = 0;
 640
 641         r = xcalloc(read_wait_nfdset, sizeof(fd_mask));
 642         e = xcalloc(read_wait_nfdset, sizeof(fd_mask));
 643         memcpy(r, read_wait, read_wait_nfdset * sizeof(fd_mask));
 644         memcpy(e, read_wait, read_wait_nfdset * sizeof(fd_mask));
 645
 646         while (select(maxfd, r, NULL, e, &seltime) == -1 &&
 647             (errno == EAGAIN || errno == EINTR))
 648                 ;
 649
 650         for (i = 0; i < maxfd; i++) {
 651                 if (FD_ISSET(i, e)) {
 652                         error("%s: exception!", fdcon[i].c_name);
 653                         confree(i);
 654                 } else if (FD_ISSET(i, r))
 655                         conread(i);
 656         }
 657         xfree(r);
 658         xfree(e);
 659
 660         c = TAILQ_FIRST(&tq);
 661         while (c && (c->c_tv.tv_sec < now.tv_sec ||
 662             (c->c_tv.tv_sec == now.tv_sec && c->c_tv.tv_usec < now.tv_usec))) {
 663                 int s = c->c_fd;
 664
 665                 c = TAILQ_NEXT(c, c_link);
 666                 conrecycle(s);
 667         }
 668 }
 669
 670 static void
 671 do_host(char *host)
 672 {
 673         char *name = strnnsep(&host, " \t\n");
 674         int j;
 675
 676         if (name == NULL)
 677                 return;
 678         for (j = KT_RSA1; j <= KT_RSA; j *= 2) {
 679                 if (get_keytypes & j) {
 680                         while (ncon >= MAXCON)
 681                                 conloop();
 682                         conalloc(name, *host ? host : name, j);
 683                 }
 684         }
 685 }
 686
 687 void
 688 fatal(const char *fmt,...)
 689 {
 690         va_list args;
 691
 692         va_start(args, fmt);
 693         do_log(SYSLOG_LEVEL_FATAL, fmt, args);
 694         va_end(args);
 695         if (nonfatal_fatal)
 696                 longjmp(kexjmp, -1);
 697         else
 698                 exit(255);
 699 }
 700
 701 static void
 702 usage(void)
 703 {
 704         fprintf(stderr,
 705             "usage: %s [-46Hv] [-f file] [-p port] [-T timeout] [-t type]\n"
 706             "\t\t   [host | addrlist namelist] ...\n",
 707             __progname);
 708         exit(1);
 709 }
 710
 711 int
 712 main(int argc, char **argv)
 713 {
 714         int debug_flag = 0, log_level = SYSLOG_LEVEL_INFO;
 715         int opt, fopt_count = 0;
 716         char *tname;
 717
 718         extern int optind;
 719         extern char *optarg;
 720
 721         TAILQ_INIT(&tq);
 722
 723         /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
 724         sanitise_stdfd();
 725
 726         if (argc <= 1)
 727                 usage();
 728
 729         while ((opt = getopt(argc, argv, "Hv46p:T:t:f:")) != -1) {
 730                 switch (opt) {
 731                 case 'H':
 732                         hash_hosts = 1;
 733                         break;
 734                 case 'p':
 735                         ssh_port = a2port(optarg);
 736                         if (ssh_port <= 0) {
 737                                 fprintf(stderr, "Bad port '%s'\n", optarg);
 738                                 exit(1);
 739                         }
 740                         break;
 741                 case 'T':
 742                         timeout = convtime(optarg);
 743                         if (timeout == -1 || timeout == 0) {
 744                                 fprintf(stderr, "Bad timeout '%s'\n", optarg);
 745                                 usage();
 746                         }
 747                         break;
 748                 case 'v':
 749                         if (!debug_flag) {
 750                                 debug_flag = 1;
 751                                 log_level = SYSLOG_LEVEL_DEBUG1;
 752                         }
 753                         else if (log_level < SYSLOG_LEVEL_DEBUG3)
 754                                 log_level++;
 755                         else
 756                                 fatal("Too high debugging level.");
 757                         break;
 758                 case 'f':
 759                         if (strcmp(optarg, "-") == 0)
 760                                 optarg = NULL;
 761                         argv[fopt_count++] = optarg;
 762                         break;
 763                 case 't':
 764                         get_keytypes = 0;
 765                         tname = strtok(optarg, ",");
 766                         while (tname) {
 767                                 int type = key_type_from_name(tname);
 768                                 switch (type) {
 769                                 case KEY_RSA1:
 770                                         get_keytypes |= KT_RSA1;
 771                                         break;
 772                                 case KEY_DSA:
 773                                         get_keytypes |= KT_DSA;
 774                                         break;
 775                                 case KEY_RSA:
 776                                         get_keytypes |= KT_RSA;
 777                                         break;
 778                                 case KEY_UNSPEC:
 779                                         fatal("unknown key type %s", tname);
 780                                 }
 781                                 tname = strtok(NULL, ",");
 782                         }
 783                         break;
 784                 case '4':
 785                         IPv4or6 = AF_INET;
 786                         break;
 787                 case '6':
 788                         IPv4or6 = AF_INET6;
 789                         break;
 790                 case '?':
 791                 default:
 792                         usage();
 793                 }
 794         }
 795         if (optind == argc && !fopt_count)
 796                 usage();
 797
 798         log_init("ssh-keyscan", log_level, SYSLOG_FACILITY_USER, 1);
 799
 800         maxfd = fdlim_get(1);
 801         if (maxfd < 0)
 802                 fatal("%s: fdlim_get: bad value", __progname);
 803         if (maxfd > MAXMAXFD)
 804                 maxfd = MAXMAXFD;
 805         if (MAXCON <= 0)
 806                 fatal("%s: not enough file descriptors", __progname);
 807         if (maxfd > fdlim_get(0))
 808                 fdlim_set(maxfd);
 809         fdcon = xcalloc(maxfd, sizeof(con));
 810
 811         read_wait_nfdset = howmany(maxfd, NFDBITS);
 812         read_wait = xcalloc(read_wait_nfdset, sizeof(fd_mask));
 813
 814         if (fopt_count) {
 815                 Linebuf *lb;
 816                 char *line;
 817                 int j;
 818
 819                 for (j = 0; j < fopt_count; j++) {
 820                         lb = Linebuf_alloc(argv[j], error);
 821                         if (!lb)
 822                                 continue;
 823                         while ((line = Linebuf_getline(lb)) != NULL)
 824                                 do_host(line);
 825                         Linebuf_free(lb);
 826                 }
 827         }
 828
 829         while (optind < argc)
 830                 do_host(argv[optind++]);
 831
 832         while (ncon > 0)
 833                 conloop();
 834
 835         return (0);
 836 }