crypto/openssh-4/ssh-keygen.c

   1 /*
   2  * Author: Tatu Ylonen <ylo@cs.hut.fi>
   3  * Copyright (c) 1994 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
   4  *                    All rights reserved
   5  * Identity and host key generation and maintenance.
   6  *
   7  * As far as I am concerned, the code I have written for this software
   8  * can be used freely for any purpose.  Any derived versions of this
   9  * software must be clearly marked as such, and if the derived work is
  10  * incompatible with the protocol description in the RFC file, it must be
  11  * called by a name other than "ssh" or "Secure Shell".
  12  */
  13
  14 #include "includes.h"
  15 RCSID("$OpenBSD: ssh-keygen.c,v 1.135 2005/11/29 02:04:55 dtucker Exp $");
  16
  17 #include <openssl/evp.h>
  18 #include <openssl/pem.h>
  19
  20 #include "xmalloc.h"
  21 #include "key.h"
  22 #include "rsa.h"
  23 #include "authfile.h"
  24 #include "uuencode.h"
  25 #include "buffer.h"
  26 #include "bufaux.h"
  27 #include "pathnames.h"
  28 #include "log.h"
  29 #include "misc.h"
  30 #include "match.h"
  31 #include "hostfile.h"
  32
  33 #ifdef SMARTCARD
  34 #include "scard.h"
  35 #endif
  36 #include "dns.h"
  37
  38 /* Number of bits in the RSA/DSA key.  This value can be set on the command line. */
  39 #define DEFAULT_BITS            2048
  40 #define DEFAULT_BITS_DSA        1024
  41 u_int32_t bits = 0;
  42
  43 /*
  44  * Flag indicating that we just want to change the passphrase.  This can be
  45  * set on the command line.
  46  */
  47 int change_passphrase = 0;
  48
  49 /*
  50  * Flag indicating that we just want to change the comment.  This can be set
  51  * on the command line.
  52  */
  53 int change_comment = 0;
  54
  55 int quiet = 0;
  56
  57 /* Flag indicating that we want to hash a known_hosts file */
  58 int hash_hosts = 0;
  59 /* Flag indicating that we want lookup a host in known_hosts file */
  60 int find_host = 0;
  61 /* Flag indicating that we want to delete a host from a known_hosts file */
  62 int delete_host = 0;
  63
  64 /* Flag indicating that we just want to see the key fingerprint */
  65 int print_fingerprint = 0;
  66 int print_bubblebabble = 0;
  67
  68 /* The identity file name, given on the command line or entered by the user. */
  69 char identity_file[1024];
  70 int have_identity = 0;
  71
  72 /* This is set to the passphrase if given on the command line. */
  73 char *identity_passphrase = NULL;
  74
  75 /* This is set to the new passphrase if given on the command line. */
  76 char *identity_new_passphrase = NULL;
  77
  78 /* This is set to the new comment if given on the command line. */
  79 char *identity_comment = NULL;
  80
  81 /* Dump public key file in format used by real and the original SSH 2 */
  82 int convert_to_ssh2 = 0;
  83 int convert_from_ssh2 = 0;
  84 int print_public = 0;
  85 int print_generic = 0;
  86
  87 char *key_type_name = NULL;
  88
  89 /* argv0 */
  90 extern char *__progname;
  91
  92 char hostname[MAXHOSTNAMELEN];
  93
  94 /* moduli.c */
  95 int gen_candidates(FILE *, u_int32_t, u_int32_t, BIGNUM *);
  96 int prime_test(FILE *, FILE *, u_int32_t, u_int32_t);
  97
  98 static void
  99 ask_filename(struct passwd *pw, const char *prompt)
 100 {
 101         char buf[1024];
 102         char *name = NULL;
 103
 104         if (key_type_name == NULL)
 105                 name = _PATH_SSH_CLIENT_ID_RSA;
 106         else
 107                 switch (key_type_from_name(key_type_name)) {
 108                 case KEY_RSA1:
 109                         name = _PATH_SSH_CLIENT_IDENTITY;
 110                         break;
 111                 case KEY_DSA:
 112                         name = _PATH_SSH_CLIENT_ID_DSA;
 113                         break;
 114                 case KEY_RSA:
 115                         name = _PATH_SSH_CLIENT_ID_RSA;
 116                         break;
 117                 default:
 118                         fprintf(stderr, "bad key type");
 119                         exit(1);
 120                         break;
 121                 }
 122
 123         snprintf(identity_file, sizeof(identity_file), "%s/%s", pw->pw_dir, name);
 124         fprintf(stderr, "%s (%s): ", prompt, identity_file);
 125         if (fgets(buf, sizeof(buf), stdin) == NULL)
 126                 exit(1);
 127         if (strchr(buf, '\n'))
 128                 *strchr(buf, '\n') = 0;
 129         if (strcmp(buf, "") != 0)
 130                 strlcpy(identity_file, buf, sizeof(identity_file));
 131         have_identity = 1;
 132 }
 133
 134 static Key *
 135 load_identity(char *filename)
 136 {
 137         char *pass;
 138         Key *prv;
 139
 140         prv = key_load_private(filename, "", NULL);
 141         if (prv == NULL) {
 142                 if (identity_passphrase)
 143                         pass = xstrdup(identity_passphrase);
 144                 else
 145                         pass = read_passphrase("Enter passphrase: ",
 146                             RP_ALLOW_STDIN);
 147                 prv = key_load_private(filename, pass, NULL);
 148                 memset(pass, 0, strlen(pass));
 149                 xfree(pass);
 150         }
 151         return prv;
 152 }
 153
 154 #define SSH_COM_PUBLIC_BEGIN            "---- BEGIN SSH2 PUBLIC KEY ----"
 155 #define SSH_COM_PUBLIC_END              "---- END SSH2 PUBLIC KEY ----"
 156 #define SSH_COM_PRIVATE_BEGIN           "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----"
 157 #define SSH_COM_PRIVATE_KEY_MAGIC       0x3f6ff9eb
 158
 159 static void
 160 do_convert_to_ssh2(struct passwd *pw)
 161 {
 162         Key *k;
 163         u_int len;
 164         u_char *blob;
 165         struct stat st;
 166
 167         if (!have_identity)
 168                 ask_filename(pw, "Enter file in which the key is");
 169         if (stat(identity_file, &st) < 0) {
 170                 perror(identity_file);
 171                 exit(1);
 172         }
 173         if ((k = key_load_public(identity_file, NULL)) == NULL) {
 174                 if ((k = load_identity(identity_file)) == NULL) {
 175                         fprintf(stderr, "load failed\n");
 176                         exit(1);
 177                 }
 178         }
 179         if (k->type == KEY_RSA1) {
 180                 fprintf(stderr, "version 1 keys are not supported\n");
 181                 exit(1);
 182         }
 183         if (key_to_blob(k, &blob, &len) <= 0) {
 184                 fprintf(stderr, "key_to_blob failed\n");
 185                 exit(1);
 186         }
 187         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_BEGIN);
 188         fprintf(stdout,
 189             "Comment: \"%u-bit %s, converted from OpenSSH by %s@%s\"\n",
 190             key_size(k), key_type(k),
 191             pw->pw_name, hostname);
 192         dump_base64(stdout, blob, len);
 193         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_END);
 194         key_free(k);
 195         xfree(blob);
 196         exit(0);
 197 }
 198
 199 static void
 200 buffer_get_bignum_bits(Buffer *b, BIGNUM *value)
 201 {
 202         u_int bignum_bits = buffer_get_int(b);
 203         u_int bytes = (bignum_bits + 7) / 8;
 204
 205         if (buffer_len(b) < bytes)
 206                 fatal("buffer_get_bignum_bits: input buffer too small: "
 207                     "need %d have %d", bytes, buffer_len(b));
 208         BN_bin2bn(buffer_ptr(b), bytes, value);
 209         buffer_consume(b, bytes);
 210 }
 211
 212 static Key *
 213 do_convert_private_ssh2_from_blob(u_char *blob, u_int blen)
 214 {
 215         Buffer b;
 216         Key *key = NULL;
 217         char *type, *cipher;
 218         u_char *sig, data[] = "abcde12345";
 219         int magic, rlen, ktype, i1, i2, i3, i4;
 220         u_int slen;
 221         u_long e;
 222
 223         buffer_init(&b);
 224         buffer_append(&b, blob, blen);
 225
 226         magic  = buffer_get_int(&b);
 227         if (magic != SSH_COM_PRIVATE_KEY_MAGIC) {
 228                 error("bad magic 0x%x != 0x%x", magic, SSH_COM_PRIVATE_KEY_MAGIC);
 229                 buffer_free(&b);
 230                 return NULL;
 231         }
 232         i1 = buffer_get_int(&b);
 233         type   = buffer_get_string(&b, NULL);
 234         cipher = buffer_get_string(&b, NULL);
 235         i2 = buffer_get_int(&b);
 236         i3 = buffer_get_int(&b);
 237         i4 = buffer_get_int(&b);
 238         debug("ignore (%d %d %d %d)", i1,i2,i3,i4);
 239         if (strcmp(cipher, "none") != 0) {
 240                 error("unsupported cipher %s", cipher);
 241                 xfree(cipher);
 242                 buffer_free(&b);
 243                 xfree(type);
 244                 return NULL;
 245         }
 246         xfree(cipher);
 247
 248         if (strstr(type, "dsa")) {
 249                 ktype = KEY_DSA;
 250         } else if (strstr(type, "rsa")) {
 251                 ktype = KEY_RSA;
 252         } else {
 253                 buffer_free(&b);
 254                 xfree(type);
 255                 return NULL;
 256         }
 257         key = key_new_private(ktype);
 258         xfree(type);
 259
 260         switch (key->type) {
 261         case KEY_DSA:
 262                 buffer_get_bignum_bits(&b, key->dsa->p);
 263                 buffer_get_bignum_bits(&b, key->dsa->g);
 264                 buffer_get_bignum_bits(&b, key->dsa->q);
 265                 buffer_get_bignum_bits(&b, key->dsa->pub_key);
 266                 buffer_get_bignum_bits(&b, key->dsa->priv_key);
 267                 break;
 268         case KEY_RSA:
 269                 e  = buffer_get_char(&b);
 270                 debug("e %lx", e);
 271                 if (e < 30) {
 272                         e <<= 8;
 273                         e += buffer_get_char(&b);
 274                         debug("e %lx", e);
 275                         e <<= 8;
 276                         e += buffer_get_char(&b);
 277                         debug("e %lx", e);
 278                 }
 279                 if (!BN_set_word(key->rsa->e, e)) {
 280                         buffer_free(&b);
 281                         key_free(key);
 282                         return NULL;
 283                 }
 284                 buffer_get_bignum_bits(&b, key->rsa->d);
 285                 buffer_get_bignum_bits(&b, key->rsa->n);
 286                 buffer_get_bignum_bits(&b, key->rsa->iqmp);
 287                 buffer_get_bignum_bits(&b, key->rsa->q);
 288                 buffer_get_bignum_bits(&b, key->rsa->p);
 289                 rsa_generate_additional_parameters(key->rsa);
 290                 break;
 291         }
 292         rlen = buffer_len(&b);
 293         if (rlen != 0)
 294                 error("do_convert_private_ssh2_from_blob: "
 295                     "remaining bytes in key blob %d", rlen);
 296         buffer_free(&b);
 297
 298         /* try the key */
 299         key_sign(key, &sig, &slen, data, sizeof(data));
 300         key_verify(key, sig, slen, data, sizeof(data));
 301         xfree(sig);
 302         return key;
 303 }
 304
 305 static void
 306 do_convert_from_ssh2(struct passwd *pw)
 307 {
 308         Key *k;
 309         int blen;
 310         u_int len;
 311         char line[1024], *p;
 312         u_char blob[8096];
 313         char encoded[8096];
 314         struct stat st;
 315         int escaped = 0, private = 0, ok;
 316         FILE *fp;
 317
 318         if (!have_identity)
 319                 ask_filename(pw, "Enter file in which the key is");
 320         if (stat(identity_file, &st) < 0) {
 321                 perror(identity_file);
 322                 exit(1);
 323         }
 324         fp = fopen(identity_file, "r");
 325         if (fp == NULL) {
 326                 perror(identity_file);
 327                 exit(1);
 328         }
 329         encoded[0] = '\0';
 330         while (fgets(line, sizeof(line), fp)) {
 331                 if (!(p = strchr(line, '\n'))) {
 332                         fprintf(stderr, "input line too long.\n");
 333                         exit(1);
 334                 }
 335                 if (p > line && p[-1] == '\\')
 336                         escaped++;
 337                 if (strncmp(line, "----", 4) == 0 ||
 338                     strstr(line, ": ") != NULL) {
 339                         if (strstr(line, SSH_COM_PRIVATE_BEGIN) != NULL)
 340                                 private = 1;
 341                         if (strstr(line, " END ") != NULL) {
 342                                 break;
 343                         }
 344                         /* fprintf(stderr, "ignore: %s", line); */
 345                         continue;
 346                 }
 347                 if (escaped) {
 348                         escaped--;
 349                         /* fprintf(stderr, "escaped: %s", line); */
 350                         continue;
 351                 }
 352                 *p = '\0';
 353                 strlcat(encoded, line, sizeof(encoded));
 354         }
 355         len = strlen(encoded);
 356         if (((len % 4) == 3) &&
 357             (encoded[len-1] == '=') &&
 358             (encoded[len-2] == '=') &&
 359             (encoded[len-3] == '='))
 360                 encoded[len-3] = '\0';
 361         blen = uudecode(encoded, blob, sizeof(blob));
 362         if (blen < 0) {
 363                 fprintf(stderr, "uudecode failed.\n");
 364                 exit(1);
 365         }
 366         k = private ?
 367             do_convert_private_ssh2_from_blob(blob, blen) :
 368             key_from_blob(blob, blen);
 369         if (k == NULL) {
 370                 fprintf(stderr, "decode blob failed.\n");
 371                 exit(1);
 372         }
 373         ok = private ?
 374             (k->type == KEY_DSA ?
 375                  PEM_write_DSAPrivateKey(stdout, k->dsa, NULL, NULL, 0, NULL, NULL) :
 376                  PEM_write_RSAPrivateKey(stdout, k->rsa, NULL, NULL, 0, NULL, NULL)) :
 377             key_write(k, stdout);
 378         if (!ok) {
 379                 fprintf(stderr, "key write failed");
 380                 exit(1);
 381         }
 382         key_free(k);
 383         if (!private)
 384                 fprintf(stdout, "\n");
 385         fclose(fp);
 386         exit(0);
 387 }
 388
 389 static void
 390 do_print_public(struct passwd *pw)
 391 {
 392         Key *prv;
 393         struct stat st;
 394
 395         if (!have_identity)
 396                 ask_filename(pw, "Enter file in which the key is");
 397         if (stat(identity_file, &st) < 0) {
 398                 perror(identity_file);
 399                 exit(1);
 400         }
 401         prv = load_identity(identity_file);
 402         if (prv == NULL) {
 403                 fprintf(stderr, "load failed\n");
 404                 exit(1);
 405         }
 406         if (!key_write(prv, stdout))
 407                 fprintf(stderr, "key_write failed");
 408         key_free(prv);
 409         fprintf(stdout, "\n");
 410         exit(0);
 411 }
 412
 413 #ifdef SMARTCARD
 414 static void
 415 do_upload(struct passwd *pw, const char *sc_reader_id)
 416 {
 417         Key *prv = NULL;
 418         struct stat st;
 419         int ret;
 420
 421         if (!have_identity)
 422                 ask_filename(pw, "Enter file in which the key is");
 423         if (stat(identity_file, &st) < 0) {
 424                 perror(identity_file);
 425                 exit(1);
 426         }
 427         prv = load_identity(identity_file);
 428         if (prv == NULL) {
 429                 error("load failed");
 430                 exit(1);
 431         }
 432         ret = sc_put_key(prv, sc_reader_id);
 433         key_free(prv);
 434         if (ret < 0)
 435                 exit(1);
 436         logit("loading key done");
 437         exit(0);
 438 }
 439
 440 static void
 441 do_download(struct passwd *pw, const char *sc_reader_id)
 442 {
 443         Key **keys = NULL;
 444         int i;
 445
 446         keys = sc_get_keys(sc_reader_id, NULL);
 447         if (keys == NULL)
 448                 fatal("cannot read public key from smartcard");
 449         for (i = 0; keys[i]; i++) {
 450                 key_write(keys[i], stdout);
 451                 key_free(keys[i]);
 452                 fprintf(stdout, "\n");
 453         }
 454         xfree(keys);
 455         exit(0);
 456 }
 457 #endif /* SMARTCARD */
 458
 459 static void
 460 do_fingerprint(struct passwd *pw)
 461 {
 462         FILE *f;
 463         Key *public;
 464         char *comment = NULL, *cp, *ep, line[16*1024], *fp;
 465         int i, skip = 0, num = 1, invalid = 1;
 466         enum fp_rep rep;
 467         enum fp_type fptype;
 468         struct stat st;
 469
 470         fptype = print_bubblebabble ? SSH_FP_SHA1 : SSH_FP_MD5;
 471         rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_HEX;
 472
 473         if (!have_identity)
 474                 ask_filename(pw, "Enter file in which the key is");
 475         if (stat(identity_file, &st) < 0) {
 476                 perror(identity_file);
 477                 exit(1);
 478         }
 479         public = key_load_public(identity_file, &comment);
 480         if (public != NULL) {
 481                 fp = key_fingerprint(public, fptype, rep);
 482                 printf("%u %s %s\n", key_size(public), fp, comment);
 483                 key_free(public);
 484                 xfree(comment);
 485                 xfree(fp);
 486                 exit(0);
 487         }
 488         if (comment)
 489                 xfree(comment);
 490
 491         f = fopen(identity_file, "r");
 492         if (f != NULL) {
 493                 while (fgets(line, sizeof(line), f)) {
 494                         i = strlen(line) - 1;
 495                         if (line[i] != '\n') {
 496                                 error("line %d too long: %.40s...", num, line);
 497                                 skip = 1;
 498                                 continue;
 499                         }
 500                         num++;
 501                         if (skip) {
 502                                 skip = 0;
 503                                 continue;
 504                         }
 505                         line[i] = '\0';
 506
 507                         /* Skip leading whitespace, empty and comment lines. */
 508                         for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
 509                                 ;
 510                         if (!*cp || *cp == '\n' || *cp == '#')
 511                                 continue ;
 512                         i = strtol(cp, &ep, 10);
 513                         if (i == 0 || ep == NULL || (*ep != ' ' && *ep != '\t')) {
 514                                 int quoted = 0;
 515                                 comment = cp;
 516                                 for (; *cp && (quoted || (*cp != ' ' &&
 517                                     *cp != '\t')); cp++) {
 518                                         if (*cp == '\\' && cp[1] == '"')
 519                                                 cp++;   /* Skip both */
 520                                         else if (*cp == '"')
 521                                                 quoted = !quoted;
 522                                 }
 523                                 if (!*cp)
 524                                         continue;
 525                                 *cp++ = '\0';
 526                         }
 527                         ep = cp;
 528                         public = key_new(KEY_RSA1);
 529                         if (key_read(public, &cp) != 1) {
 530                                 cp = ep;
 531                                 key_free(public);
 532                                 public = key_new(KEY_UNSPEC);
 533                                 if (key_read(public, &cp) != 1) {
 534                                         key_free(public);
 535                                         continue;
 536                                 }
 537                         }
 538                         comment = *cp ? cp : comment;
 539                         fp = key_fingerprint(public, fptype, rep);
 540                         printf("%u %s %s\n", key_size(public), fp,
 541                             comment ? comment : "no comment");
 542                         xfree(fp);
 543                         key_free(public);
 544                         invalid = 0;
 545                 }
 546                 fclose(f);
 547         }
 548         if (invalid) {
 549                 printf("%s is not a public key file.\n", identity_file);
 550                 exit(1);
 551         }
 552         exit(0);
 553 }
 554
 555 static void
 556 print_host(FILE *f, char *name, Key *public, int hash)
 557 {
 558         if (hash && (name = host_hash(name, NULL, 0)) == NULL)
 559                 fatal("hash_host failed");
 560         fprintf(f, "%s ", name);
 561         if (!key_write(public, f))
 562                 fatal("key_write failed");
 563         fprintf(f, "\n");
 564 }
 565
 566 static void
 567 do_known_hosts(struct passwd *pw, const char *name)
 568 {
 569         FILE *in, *out = stdout;
 570         Key *public;
 571         char *cp, *cp2, *kp, *kp2;
 572         char line[16*1024], tmp[MAXPATHLEN], old[MAXPATHLEN];
 573         int c, i, skip = 0, inplace = 0, num = 0, invalid = 0, has_unhashed = 0;
 574
 575         if (!have_identity) {
 576                 cp = tilde_expand_filename(_PATH_SSH_USER_HOSTFILE, pw->pw_uid);
 577                 if (strlcpy(identity_file, cp, sizeof(identity_file)) >=
 578                     sizeof(identity_file))
 579                         fatal("Specified known hosts path too long");
 580                 xfree(cp);
 581                 have_identity = 1;
 582         }
 583         if ((in = fopen(identity_file, "r")) == NULL)
 584                 fatal("fopen: %s", strerror(errno));
 585
 586         /*
 587          * Find hosts goes to stdout, hash and deletions happen in-place
 588          * A corner case is ssh-keygen -HF foo, which should go to stdout
 589          */
 590         if (!find_host && (hash_hosts || delete_host)) {
 591                 if (strlcpy(tmp, identity_file, sizeof(tmp)) >= sizeof(tmp) ||
 592                     strlcat(tmp, ".XXXXXXXXXX", sizeof(tmp)) >= sizeof(tmp) ||
 593                     strlcpy(old, identity_file, sizeof(old)) >= sizeof(old) ||
 594                     strlcat(old, ".old", sizeof(old)) >= sizeof(old))
 595                         fatal("known_hosts path too long");
 596                 umask(077);
 597                 if ((c = mkstemp(tmp)) == -1)
 598                         fatal("mkstemp: %s", strerror(errno));
 599                 if ((out = fdopen(c, "w")) == NULL) {
 600                         c = errno;
 601                         unlink(tmp);
 602                         fatal("fdopen: %s", strerror(c));
 603                 }
 604                 inplace = 1;
 605         }
 606
 607         while (fgets(line, sizeof(line), in)) {
 608                 num++;
 609                 i = strlen(line) - 1;
 610                 if (line[i] != '\n') {
 611                         error("line %d too long: %.40s...", num, line);
 612                         skip = 1;
 613                         invalid = 1;
 614                         continue;
 615                 }
 616                 if (skip) {
 617                         skip = 0;
 618                         continue;
 619                 }
 620                 line[i] = '\0';
 621
 622                 /* Skip leading whitespace, empty and comment lines. */
 623                 for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
 624                         ;
 625                 if (!*cp || *cp == '\n' || *cp == '#') {
 626                         if (inplace)
 627                                 fprintf(out, "%s\n", cp);
 628                         continue;
 629                 }
 630                 /* Find the end of the host name portion. */
 631                 for (kp = cp; *kp && *kp != ' ' && *kp != '\t'; kp++)
 632                         ;
 633                 if (*kp == '\0' || *(kp + 1) == '\0') {
 634                         error("line %d missing key: %.40s...",
 635                             num, line);
 636                         invalid = 1;
 637                         continue;
 638                 }
 639                 *kp++ = '\0';
 640                 kp2 = kp;
 641
 642                 public = key_new(KEY_RSA1);
 643                 if (key_read(public, &kp) != 1) {
 644                         kp = kp2;
 645                         key_free(public);
 646                         public = key_new(KEY_UNSPEC);
 647                         if (key_read(public, &kp) != 1) {
 648                                 error("line %d invalid key: %.40s...",
 649                                     num, line);
 650                                 key_free(public);
 651                                 invalid = 1;
 652                                 continue;
 653                         }
 654                 }
 655
 656                 if (*cp == HASH_DELIM) {
 657                         if (find_host || delete_host) {
 658                                 cp2 = host_hash(name, cp, strlen(cp));
 659                                 if (cp2 == NULL) {
 660                                         error("line %d: invalid hashed "
 661                                             "name: %.64s...", num, line);
 662                                         invalid = 1;
 663                                         continue;
 664                                 }
 665                                 c = (strcmp(cp2, cp) == 0);
 666                                 if (find_host && c) {
 667                                         printf("# Host %s found: "
 668                                             "line %d type %s\n", name,
 669                                             num, key_type(public));
 670                                         print_host(out, cp, public, 0);
 671                                 }
 672                                 if (delete_host && !c)
 673                                         print_host(out, cp, public, 0);
 674                         } else if (hash_hosts)
 675                                 print_host(out, cp, public, 0);
 676                 } else {
 677                         if (find_host || delete_host) {
 678                                 c = (match_hostname(name, cp,
 679                                     strlen(cp)) == 1);
 680                                 if (find_host && c) {
 681                                         printf("# Host %s found: "
 682                                             "line %d type %s\n", name,
 683                                             num, key_type(public));
 684                                         print_host(out, cp, public, hash_hosts);
 685                                 }
 686                                 if (delete_host && !c)
 687                                         print_host(out, cp, public, 0);
 688                         } else if (hash_hosts) {
 689                                 for (cp2 = strsep(&cp, ",");
 690                                     cp2 != NULL && *cp2 != '\0';
 691                                     cp2 = strsep(&cp, ",")) {
 692                                         if (strcspn(cp2, "*?!") != strlen(cp2))
 693                                                 fprintf(stderr, "Warning: "
 694                                                     "ignoring host name with "
 695                                                     "metacharacters: %.64s\n",
 696                                                     cp2);
 697                                         else
 698                                                 print_host(out, cp2, public, 1);
 699                                 }
 700                                 has_unhashed = 1;
 701                         }
 702                 }
 703                 key_free(public);
 704         }
 705         fclose(in);
 706
 707         if (invalid) {
 708                 fprintf(stderr, "%s is not a valid known_host file.\n",
 709                     identity_file);
 710                 if (inplace) {
 711                         fprintf(stderr, "Not replacing existing known_hosts "
 712                             "file because of errors\n");
 713                         fclose(out);
 714                         unlink(tmp);
 715                 }
 716                 exit(1);
 717         }
 718
 719         if (inplace) {
 720                 fclose(out);
 721
 722                 /* Backup existing file */
 723                 if (unlink(old) == -1 && errno != ENOENT)
 724                         fatal("unlink %.100s: %s", old, strerror(errno));
 725                 if (link(identity_file, old) == -1)
 726                         fatal("link %.100s to %.100s: %s", identity_file, old,
 727                             strerror(errno));
 728                 /* Move new one into place */
 729                 if (rename(tmp, identity_file) == -1) {
 730                         error("rename\"%s\" to \"%s\": %s", tmp, identity_file,
 731                             strerror(errno));
 732                         unlink(tmp);
 733                         unlink(old);
 734                         exit(1);
 735                 }
 736
 737                 fprintf(stderr, "%s updated.\n", identity_file);
 738                 fprintf(stderr, "Original contents retained as %s\n", old);
 739                 if (has_unhashed) {
 740                         fprintf(stderr, "WARNING: %s contains unhashed "
 741                             "entries\n", old);
 742                         fprintf(stderr, "Delete this file to ensure privacy "
 743                             "of hostnames\n");
 744                 }
 745         }
 746
 747         exit(0);
 748 }
 749
 750 /*
 751  * Perform changing a passphrase.  The argument is the passwd structure
 752  * for the current user.
 753  */
 754 static void
 755 do_change_passphrase(struct passwd *pw)
 756 {
 757         char *comment;
 758         char *old_passphrase, *passphrase1, *passphrase2;
 759         struct stat st;
 760         Key *private;
 761
 762         if (!have_identity)
 763                 ask_filename(pw, "Enter file in which the key is");
 764         if (stat(identity_file, &st) < 0) {
 765                 perror(identity_file);
 766                 exit(1);
 767         }
 768         /* Try to load the file with empty passphrase. */
 769         private = key_load_private(identity_file, "", &comment);
 770         if (private == NULL) {
 771                 if (identity_passphrase)
 772                         old_passphrase = xstrdup(identity_passphrase);
 773                 else
 774                         old_passphrase =
 775                             read_passphrase("Enter old passphrase: ",
 776                             RP_ALLOW_STDIN);
 777                 private = key_load_private(identity_file, old_passphrase,
 778                     &comment);
 779                 memset(old_passphrase, 0, strlen(old_passphrase));
 780                 xfree(old_passphrase);
 781                 if (private == NULL) {
 782                         printf("Bad passphrase.\n");
 783                         exit(1);
 784                 }
 785         }
 786         printf("Key has comment '%s'\n", comment);
 787
 788         /* Ask the new passphrase (twice). */
 789         if (identity_new_passphrase) {
 790                 passphrase1 = xstrdup(identity_new_passphrase);
 791                 passphrase2 = NULL;
 792         } else {
 793                 passphrase1 =
 794                         read_passphrase("Enter new passphrase (empty for no "
 795                             "passphrase): ", RP_ALLOW_STDIN);
 796                 passphrase2 = read_passphrase("Enter same passphrase again: ",
 797                     RP_ALLOW_STDIN);
 798
 799                 /* Verify that they are the same. */
 800                 if (strcmp(passphrase1, passphrase2) != 0) {
 801                         memset(passphrase1, 0, strlen(passphrase1));
 802                         memset(passphrase2, 0, strlen(passphrase2));
 803                         xfree(passphrase1);
 804                         xfree(passphrase2);
 805                         printf("Pass phrases do not match.  Try again.\n");
 806                         exit(1);
 807                 }
 808                 /* Destroy the other copy. */
 809                 memset(passphrase2, 0, strlen(passphrase2));
 810                 xfree(passphrase2);
 811         }
 812
 813         /* Save the file using the new passphrase. */
 814         if (!key_save_private(private, identity_file, passphrase1, comment)) {
 815                 printf("Saving the key failed: %s.\n", identity_file);
 816                 memset(passphrase1, 0, strlen(passphrase1));
 817                 xfree(passphrase1);
 818                 key_free(private);
 819                 xfree(comment);
 820                 exit(1);
 821         }
 822         /* Destroy the passphrase and the copy of the key in memory. */
 823         memset(passphrase1, 0, strlen(passphrase1));
 824         xfree(passphrase1);
 825         key_free(private);               /* Destroys contents */
 826         xfree(comment);
 827
 828         printf("Your identification has been saved with the new passphrase.\n");
 829         exit(0);
 830 }
 831
 832 /*
 833  * Print the SSHFP RR.
 834  */
 835 static void
 836 do_print_resource_record(struct passwd *pw, char *hname)
 837 {
 838         Key *public;
 839         char *comment = NULL;
 840         struct stat st;
 841
 842         if (!have_identity)
 843                 ask_filename(pw, "Enter file in which the key is");
 844         if (stat(identity_file, &st) < 0) {
 845                 perror(identity_file);
 846                 exit(1);
 847         }
 848         public = key_load_public(identity_file, &comment);
 849         if (public != NULL) {
 850                 export_dns_rr(hname, public, stdout, print_generic);
 851                 key_free(public);
 852                 xfree(comment);
 853                 exit(0);
 854         }
 855         if (comment)
 856                 xfree(comment);
 857
 858         printf("failed to read v2 public key from %s.\n", identity_file);
 859         exit(1);
 860 }
 861
 862 /*
 863  * Change the comment of a private key file.
 864  */
 865 static void
 866 do_change_comment(struct passwd *pw)
 867 {
 868         char new_comment[1024], *comment, *passphrase;
 869         Key *private;
 870         Key *public;
 871         struct stat st;
 872         FILE *f;
 873         int fd;
 874
 875         if (!have_identity)
 876                 ask_filename(pw, "Enter file in which the key is");
 877         if (stat(identity_file, &st) < 0) {
 878                 perror(identity_file);
 879                 exit(1);
 880         }
 881         private = key_load_private(identity_file, "", &comment);
 882         if (private == NULL) {
 883                 if (identity_passphrase)
 884                         passphrase = xstrdup(identity_passphrase);
 885                 else if (identity_new_passphrase)
 886                         passphrase = xstrdup(identity_new_passphrase);
 887                 else
 888                         passphrase = read_passphrase("Enter passphrase: ",
 889                             RP_ALLOW_STDIN);
 890                 /* Try to load using the passphrase. */
 891                 private = key_load_private(identity_file, passphrase, &comment);
 892                 if (private == NULL) {
 893                         memset(passphrase, 0, strlen(passphrase));
 894                         xfree(passphrase);
 895                         printf("Bad passphrase.\n");
 896                         exit(1);
 897                 }
 898         } else {
 899                 passphrase = xstrdup("");
 900         }
 901         if (private->type != KEY_RSA1) {
 902                 fprintf(stderr, "Comments are only supported for RSA1 keys.\n");
 903                 key_free(private);
 904                 exit(1);
 905         }
 906         printf("Key now has comment '%s'\n", comment);
 907
 908         if (identity_comment) {
 909                 strlcpy(new_comment, identity_comment, sizeof(new_comment));
 910         } else {
 911                 printf("Enter new comment: ");
 912                 fflush(stdout);
 913                 if (!fgets(new_comment, sizeof(new_comment), stdin)) {
 914                         memset(passphrase, 0, strlen(passphrase));
 915                         key_free(private);
 916                         exit(1);
 917                 }
 918                 if (strchr(new_comment, '\n'))
 919                         *strchr(new_comment, '\n') = 0;
 920         }
 921
 922         /* Save the file using the new passphrase. */
 923         if (!key_save_private(private, identity_file, passphrase, new_comment)) {
 924                 printf("Saving the key failed: %s.\n", identity_file);
 925                 memset(passphrase, 0, strlen(passphrase));
 926                 xfree(passphrase);
 927                 key_free(private);
 928                 xfree(comment);
 929                 exit(1);
 930         }
 931         memset(passphrase, 0, strlen(passphrase));
 932         xfree(passphrase);
 933         public = key_from_private(private);
 934         key_free(private);
 935
 936         strlcat(identity_file, ".pub", sizeof(identity_file));
 937         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 938         if (fd == -1) {
 939                 printf("Could not save your public key in %s\n", identity_file);
 940                 exit(1);
 941         }
 942         f = fdopen(fd, "w");
 943         if (f == NULL) {
 944                 printf("fdopen %s failed", identity_file);
 945                 exit(1);
 946         }
 947         if (!key_write(public, f))
 948                 fprintf(stderr, "write key failed");
 949         key_free(public);
 950         fprintf(f, " %s\n", new_comment);
 951         fclose(f);
 952
 953         xfree(comment);
 954
 955         printf("The comment in your key file has been changed.\n");
 956         exit(0);
 957 }
 958
 959 static void
 960 usage(void)
 961 {
 962         fprintf(stderr, "Usage: %s [options]\n", __progname);
 963         fprintf(stderr, "Options:\n");
 964         fprintf(stderr, "  -a trials   Number of trials for screening DH-GEX moduli.\n");
 965         fprintf(stderr, "  -B          Show bubblebabble digest of key file.\n");
 966         fprintf(stderr, "  -b bits     Number of bits in the key to create.\n");
 967         fprintf(stderr, "  -C comment  Provide new comment.\n");
 968         fprintf(stderr, "  -c          Change comment in private and public key files.\n");
 969 #ifdef SMARTCARD
 970         fprintf(stderr, "  -D reader   Download public key from smartcard.\n");
 971 #endif /* SMARTCARD */
 972         fprintf(stderr, "  -e          Convert OpenSSH to IETF SECSH key file.\n");
 973         fprintf(stderr, "  -F hostname Find hostname in known hosts file.\n");
 974         fprintf(stderr, "  -f filename Filename of the key file.\n");
 975         fprintf(stderr, "  -G file     Generate candidates for DH-GEX moduli.\n");
 976         fprintf(stderr, "  -g          Use generic DNS resource record format.\n");
 977         fprintf(stderr, "  -H          Hash names in known_hosts file.\n");
 978         fprintf(stderr, "  -i          Convert IETF SECSH to OpenSSH key file.\n");
 979         fprintf(stderr, "  -l          Show fingerprint of key file.\n");
 980         fprintf(stderr, "  -M memory   Amount of memory (MB) to use for generating DH-GEX moduli.\n");
 981         fprintf(stderr, "  -N phrase   Provide new passphrase.\n");
 982         fprintf(stderr, "  -P phrase   Provide old passphrase.\n");
 983         fprintf(stderr, "  -p          Change passphrase of private key file.\n");
 984         fprintf(stderr, "  -q          Quiet.\n");
 985         fprintf(stderr, "  -R hostname Remove host from known_hosts file.\n");
 986         fprintf(stderr, "  -r hostname Print DNS resource record.\n");
 987         fprintf(stderr, "  -S start    Start point (hex) for generating DH-GEX moduli.\n");
 988         fprintf(stderr, "  -T file     Screen candidates for DH-GEX moduli.\n");
 989         fprintf(stderr, "  -t type     Specify type of key to create.\n");
 990 #ifdef SMARTCARD
 991         fprintf(stderr, "  -U reader   Upload private key to smartcard.\n");
 992 #endif /* SMARTCARD */
 993         fprintf(stderr, "  -v          Verbose.\n");
 994         fprintf(stderr, "  -W gen      Generator to use for generating DH-GEX moduli.\n");
 995         fprintf(stderr, "  -y          Read private key file and print public key.\n");
 996
 997         exit(1);
 998 }
 999
1000 /*
1001  * Main program for key management.
1002  */
1003 int
1004 main(int ac, char **av)
1005 {
1006         char dotsshdir[MAXPATHLEN], comment[1024], *passphrase1, *passphrase2;
1007         char out_file[MAXPATHLEN], *reader_id = NULL;
1008         char *rr_hostname = NULL;
1009         Key *private, *public;
1010         struct passwd *pw;
1011         struct stat st;
1012         int opt, type, fd, download = 0;
1013         u_int32_t memory = 0, generator_wanted = 0, trials = 100;
1014         int do_gen_candidates = 0, do_screen_candidates = 0;
1015         int log_level = SYSLOG_LEVEL_INFO;
1016         BIGNUM *start = NULL;
1017         FILE *f;
1018         const char *errstr;
1019
1020         extern int optind;
1021         extern char *optarg;
1022
1023         /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
1024         sanitise_stdfd();
1025
1026         __progname = ssh_get_progname(av[0]);
1027
1028         SSLeay_add_all_algorithms();
1029         log_init(av[0], SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_USER, 1);
1030
1031         init_rng();
1032         seed_rng();
1033
1034         /* we need this for the home * directory.  */
1035         pw = getpwuid(getuid());
1036         if (!pw) {
1037                 printf("You don't exist, go away!\n");
1038                 exit(1);
1039         }
1040         if (gethostname(hostname, sizeof(hostname)) < 0) {
1041                 perror("gethostname");
1042                 exit(1);
1043         }
1044
1045         while ((opt = getopt(ac, av,
1046             "degiqpclBHvxXyF:b:f:t:U:D:P:N:C:r:g:R:T:G:M:S:a:W:")) != -1) {
1047                 switch (opt) {
1048                 case 'b':
1049                         bits = strtonum(optarg, 768, 32768, &errstr);
1050                         if (errstr)
1051                                 fatal("Bits has bad value %s (%s)",
1052                                         optarg, errstr);
1053                         break;
1054                 case 'F':
1055                         find_host = 1;
1056                         rr_hostname = optarg;
1057                         break;
1058                 case 'H':
1059                         hash_hosts = 1;
1060                         break;
1061                 case 'R':
1062                         delete_host = 1;
1063                         rr_hostname = optarg;
1064                         break;
1065                 case 'l':
1066                         print_fingerprint = 1;
1067                         break;
1068                 case 'B':
1069                         print_bubblebabble = 1;
1070                         break;
1071                 case 'p':
1072                         change_passphrase = 1;
1073                         break;
1074                 case 'c':
1075                         change_comment = 1;
1076                         break;
1077                 case 'f':
1078                         if (strlcpy(identity_file, optarg, sizeof(identity_file)) >=
1079                             sizeof(identity_file))
1080                                 fatal("Identity filename too long");
1081                         have_identity = 1;
1082                         break;
1083                 case 'g':
1084                         print_generic = 1;
1085                         break;
1086                 case 'P':
1087                         identity_passphrase = optarg;
1088                         break;
1089                 case 'N':
1090                         identity_new_passphrase = optarg;
1091                         break;
1092                 case 'C':
1093                         identity_comment = optarg;
1094                         break;
1095                 case 'q':
1096                         quiet = 1;
1097                         break;
1098                 case 'e':
1099                 case 'x':
1100                         /* export key */
1101                         convert_to_ssh2 = 1;
1102                         break;
1103                 case 'i':
1104                 case 'X':
1105                         /* import key */
1106                         convert_from_ssh2 = 1;
1107                         break;
1108                 case 'y':
1109                         print_public = 1;
1110                         break;
1111                 case 'd':
1112                         key_type_name = "dsa";
1113                         break;
1114                 case 't':
1115                         key_type_name = optarg;
1116                         break;
1117                 case 'D':
1118                         download = 1;
1119                 case 'U':
1120                         reader_id = optarg;
1121                         break;
1122                 case 'v':
1123                         if (log_level == SYSLOG_LEVEL_INFO)
1124                                 log_level = SYSLOG_LEVEL_DEBUG1;
1125                         else {
1126                                 if (log_level >= SYSLOG_LEVEL_DEBUG1 &&
1127                                     log_level < SYSLOG_LEVEL_DEBUG3)
1128                                         log_level++;
1129                         }
1130                         break;
1131                 case 'r':
1132                         rr_hostname = optarg;
1133                         break;
1134                 case 'W':
1135                         generator_wanted = strtonum(optarg, 1, UINT_MAX, &errstr);
1136                         if (errstr)
1137                                 fatal("Desired generator has bad value: %s (%s)",
1138                                         optarg, errstr);
1139                         break;
1140                 case 'a':
1141                         trials = strtonum(optarg, 1, UINT_MAX, &errstr);
1142                         if (errstr)
1143                                 fatal("Invalid number of trials: %s (%s)",
1144                                         optarg, errstr);
1145                         break;
1146                 case 'M':
1147                         memory = strtonum(optarg, 1, UINT_MAX, &errstr);
1148                         if (errstr) {
1149                                 fatal("Memory limit is %s: %s", errstr, optarg);
1150                         }
1151                         break;
1152                 case 'G':
1153                         do_gen_candidates = 1;
1154                         if (strlcpy(out_file, optarg, sizeof(out_file)) >=
1155                             sizeof(out_file))
1156                                 fatal("Output filename too long");
1157                         break;
1158                 case 'T':
1159                         do_screen_candidates = 1;
1160                         if (strlcpy(out_file, optarg, sizeof(out_file)) >=
1161                             sizeof(out_file))
1162                                 fatal("Output filename too long");
1163                         break;
1164                 case 'S':
1165                         /* XXX - also compare length against bits */
1166                         if (BN_hex2bn(&start, optarg) == 0)
1167                                 fatal("Invalid start point.");
1168                         break;
1169                 case '?':
1170                 default:
1171                         usage();
1172                 }
1173         }
1174
1175         /* reinit */
1176         log_init(av[0], log_level, SYSLOG_FACILITY_USER, 1);
1177
1178         if (optind < ac) {
1179                 printf("Too many arguments.\n");
1180                 usage();
1181         }
1182         if (change_passphrase && change_comment) {
1183                 printf("Can only have one of -p and -c.\n");
1184                 usage();
1185         }
1186         if (delete_host || hash_hosts || find_host)
1187                 do_known_hosts(pw, rr_hostname);
1188         if (print_fingerprint || print_bubblebabble)
1189                 do_fingerprint(pw);
1190         if (change_passphrase)
1191                 do_change_passphrase(pw);
1192         if (change_comment)
1193                 do_change_comment(pw);
1194         if (convert_to_ssh2)
1195                 do_convert_to_ssh2(pw);
1196         if (convert_from_ssh2)
1197                 do_convert_from_ssh2(pw);
1198         if (print_public)
1199                 do_print_public(pw);
1200         if (rr_hostname != NULL) {
1201                 do_print_resource_record(pw, rr_hostname);
1202         }
1203         if (reader_id != NULL) {
1204 #ifdef SMARTCARD
1205                 if (download)
1206                         do_download(pw, reader_id);
1207                 else
1208                         do_upload(pw, reader_id);
1209 #else /* SMARTCARD */
1210                 fatal("no support for smartcards.");
1211 #endif /* SMARTCARD */
1212         }
1213
1214         if (do_gen_candidates) {
1215                 FILE *out = fopen(out_file, "w");
1216
1217                 if (out == NULL) {
1218                         error("Couldn't open modulus candidate file \"%s\": %s",
1219                             out_file, strerror(errno));
1220                         return (1);
1221                 }
1222                 if (bits == 0)
1223                         bits = DEFAULT_BITS;
1224                 if (gen_candidates(out, memory, bits, start) != 0)
1225                         fatal("modulus candidate generation failed");
1226
1227                 return (0);
1228         }
1229
1230         if (do_screen_candidates) {
1231                 FILE *in;
1232                 FILE *out = fopen(out_file, "w");
1233
1234                 if (have_identity && strcmp(identity_file, "-") != 0) {
1235                         if ((in = fopen(identity_file, "r")) == NULL) {
1236                                 fatal("Couldn't open modulus candidate "
1237                                     "file \"%s\": %s", identity_file,
1238                                     strerror(errno));
1239                         }
1240                 } else
1241                         in = stdin;
1242
1243                 if (out == NULL) {
1244                         fatal("Couldn't open moduli file \"%s\": %s",
1245                             out_file, strerror(errno));
1246                 }
1247                 if (prime_test(in, out, trials, generator_wanted) != 0)
1248                         fatal("modulus screening failed");
1249                 return (0);
1250         }
1251
1252         arc4random_stir();
1253
1254         if (key_type_name == NULL)
1255                 key_type_name = "rsa";
1256
1257         type = key_type_from_name(key_type_name);
1258         if (type == KEY_UNSPEC) {
1259                 fprintf(stderr, "unknown key type %s\n", key_type_name);
1260                 exit(1);
1261         }
1262         if (bits == 0)
1263                 bits = (type == KEY_DSA) ? DEFAULT_BITS_DSA : DEFAULT_BITS;
1264         if (type == KEY_DSA && bits != 1024)
1265                 fatal("DSA keys must be 1024 bits");
1266         if (!quiet)
1267                 printf("Generating public/private %s key pair.\n", key_type_name);
1268         private = key_generate(type, bits);
1269         if (private == NULL) {
1270                 fprintf(stderr, "key_generate failed");
1271                 exit(1);
1272         }
1273         public  = key_from_private(private);
1274
1275         if (!have_identity)
1276                 ask_filename(pw, "Enter file in which to save the key");
1277
1278         /* Create ~/.ssh directory if it doesn't already exist. */
1279         snprintf(dotsshdir, sizeof dotsshdir, "%s/%s", pw->pw_dir, _PATH_SSH_USER_DIR);
1280         if (strstr(identity_file, dotsshdir) != NULL &&
1281             stat(dotsshdir, &st) < 0) {
1282                 if (mkdir(dotsshdir, 0700) < 0)
1283                         error("Could not create directory '%s'.", dotsshdir);
1284                 else if (!quiet)
1285                         printf("Created directory '%s'.\n", dotsshdir);
1286         }
1287         /* If the file already exists, ask the user to confirm. */
1288         if (stat(identity_file, &st) >= 0) {
1289                 char yesno[3];
1290                 printf("%s already exists.\n", identity_file);
1291                 printf("Overwrite (y/n)? ");
1292                 fflush(stdout);
1293                 if (fgets(yesno, sizeof(yesno), stdin) == NULL)
1294                         exit(1);
1295                 if (yesno[0] != 'y' && yesno[0] != 'Y')
1296                         exit(1);
1297         }
1298         /* Ask for a passphrase (twice). */
1299         if (identity_passphrase)
1300                 passphrase1 = xstrdup(identity_passphrase);
1301         else if (identity_new_passphrase)
1302                 passphrase1 = xstrdup(identity_new_passphrase);
1303         else {
1304 passphrase_again:
1305                 passphrase1 =
1306                         read_passphrase("Enter passphrase (empty for no "
1307                             "passphrase): ", RP_ALLOW_STDIN);
1308                 passphrase2 = read_passphrase("Enter same passphrase again: ",
1309                     RP_ALLOW_STDIN);
1310                 if (strcmp(passphrase1, passphrase2) != 0) {
1311                         /*
1312                          * The passphrases do not match.  Clear them and
1313                          * retry.
1314                          */
1315                         memset(passphrase1, 0, strlen(passphrase1));
1316                         memset(passphrase2, 0, strlen(passphrase2));
1317                         xfree(passphrase1);
1318                         xfree(passphrase2);
1319                         printf("Passphrases do not match.  Try again.\n");
1320                         goto passphrase_again;
1321                 }
1322                 /* Clear the other copy of the passphrase. */
1323                 memset(passphrase2, 0, strlen(passphrase2));
1324                 xfree(passphrase2);
1325         }
1326
1327         if (identity_comment) {
1328                 strlcpy(comment, identity_comment, sizeof(comment));
1329         } else {
1330                 /* Create default commend field for the passphrase. */
1331                 snprintf(comment, sizeof comment, "%s@%s", pw->pw_name, hostname);
1332         }
1333
1334         /* Save the key with the given passphrase and comment. */
1335         if (!key_save_private(private, identity_file, passphrase1, comment)) {
1336                 printf("Saving the key failed: %s.\n", identity_file);
1337                 memset(passphrase1, 0, strlen(passphrase1));
1338                 xfree(passphrase1);
1339                 exit(1);
1340         }
1341         /* Clear the passphrase. */
1342         memset(passphrase1, 0, strlen(passphrase1));
1343         xfree(passphrase1);
1344
1345         /* Clear the private key and the random number generator. */
1346         key_free(private);
1347         arc4random_stir();
1348
1349         if (!quiet)
1350                 printf("Your identification has been saved in %s.\n", identity_file);
1351
1352         strlcat(identity_file, ".pub", sizeof(identity_file));
1353         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
1354         if (fd == -1) {
1355                 printf("Could not save your public key in %s\n", identity_file);
1356                 exit(1);
1357         }
1358         f = fdopen(fd, "w");
1359         if (f == NULL) {
1360                 printf("fdopen %s failed", identity_file);
1361                 exit(1);
1362         }
1363         if (!key_write(public, f))
1364                 fprintf(stderr, "write key failed");
1365         fprintf(f, " %s\n", comment);
1366         fclose(f);
1367
1368         if (!quiet) {
1369                 char *fp = key_fingerprint(public, SSH_FP_MD5, SSH_FP_HEX);
1370                 printf("Your public key has been saved in %s.\n",
1371                     identity_file);
1372                 printf("The key fingerprint is:\n");
1373                 printf("%s %s\n", fp, comment);
1374                 xfree(fp);
1375         }
1376
1377         key_free(public);
1378         exit(0);
1379 }