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 1.136 2006/02/20 17:19:54 stevesk Exp $");
  16
  17 #include <sys/types.h>
  18 #include <sys/stat.h>
  19
  20 #include <openssl/evp.h>
  21 #include <openssl/pem.h>
  22
  23 #include "xmalloc.h"
  24 #include "key.h"
  25 #include "rsa.h"
  26 #include "authfile.h"
  27 #include "uuencode.h"
  28 #include "buffer.h"
  29 #include "bufaux.h"
  30 #include "pathnames.h"
  31 #include "log.h"
  32 #include "misc.h"
  33 #include "match.h"
  34 #include "hostfile.h"
  35
  36 #ifdef SMARTCARD
  37 #include "scard.h"
  38 #endif
  39 #include "dns.h"
  40
  41 /* Number of bits in the RSA/DSA key.  This value can be set on the command line. */
  42 #define DEFAULT_BITS            2048
  43 #define DEFAULT_BITS_DSA        1024
  44 u_int32_t bits = 0;
  45
  46 /*
  47  * Flag indicating that we just want to change the passphrase.  This can be
  48  * set on the command line.
  49  */
  50 int change_passphrase = 0;
  51
  52 /*
  53  * Flag indicating that we just want to change the comment.  This can be set
  54  * on the command line.
  55  */
  56 int change_comment = 0;
  57
  58 int quiet = 0;
  59
  60 /* Flag indicating that we want to hash a known_hosts file */
  61 int hash_hosts = 0;
  62 /* Flag indicating that we want lookup a host in known_hosts file */
  63 int find_host = 0;
  64 /* Flag indicating that we want to delete a host from a known_hosts file */
  65 int delete_host = 0;
  66
  67 /* Flag indicating that we just want to see the key fingerprint */
  68 int print_fingerprint = 0;
  69 int print_bubblebabble = 0;
  70
  71 /* The identity file name, given on the command line or entered by the user. */
  72 char identity_file[1024];
  73 int have_identity = 0;
  74
  75 /* This is set to the passphrase if given on the command line. */
  76 char *identity_passphrase = NULL;
  77
  78 /* This is set to the new passphrase if given on the command line. */
  79 char *identity_new_passphrase = NULL;
  80
  81 /* This is set to the new comment if given on the command line. */
  82 char *identity_comment = NULL;
  83
  84 /* Dump public key file in format used by real and the original SSH 2 */
  85 int convert_to_ssh2 = 0;
  86 int convert_from_ssh2 = 0;
  87 int print_public = 0;
  88 int print_generic = 0;
  89
  90 char *key_type_name = NULL;
  91
  92 /* argv0 */
  93 extern char *__progname;
  94
  95 char hostname[MAXHOSTNAMELEN];
  96
  97 /* moduli.c */
  98 int gen_candidates(FILE *, u_int32_t, u_int32_t, BIGNUM *);
  99 int prime_test(FILE *, FILE *, u_int32_t, u_int32_t);
 100
 101 static void
 102 ask_filename(struct passwd *pw, const char *prompt)
 103 {
 104         char buf[1024];
 105         char *name = NULL;
 106
 107         if (key_type_name == NULL)
 108                 name = _PATH_SSH_CLIENT_ID_RSA;
 109         else
 110                 switch (key_type_from_name(key_type_name)) {
 111                 case KEY_RSA1:
 112                         name = _PATH_SSH_CLIENT_IDENTITY;
 113                         break;
 114                 case KEY_DSA:
 115                         name = _PATH_SSH_CLIENT_ID_DSA;
 116                         break;
 117                 case KEY_RSA:
 118                         name = _PATH_SSH_CLIENT_ID_RSA;
 119                         break;
 120                 default:
 121                         fprintf(stderr, "bad key type");
 122                         exit(1);
 123                         break;
 124                 }
 125
 126         snprintf(identity_file, sizeof(identity_file), "%s/%s", pw->pw_dir, name);
 127         fprintf(stderr, "%s (%s): ", prompt, identity_file);
 128         if (fgets(buf, sizeof(buf), stdin) == NULL)
 129                 exit(1);
 130         if (strchr(buf, '\n'))
 131                 *strchr(buf, '\n') = 0;
 132         if (strcmp(buf, "") != 0)
 133                 strlcpy(identity_file, buf, sizeof(identity_file));
 134         have_identity = 1;
 135 }
 136
 137 static Key *
 138 load_identity(char *filename)
 139 {
 140         char *pass;
 141         Key *prv;
 142
 143         prv = key_load_private(filename, "", NULL);
 144         if (prv == NULL) {
 145                 if (identity_passphrase)
 146                         pass = xstrdup(identity_passphrase);
 147                 else
 148                         pass = read_passphrase("Enter passphrase: ",
 149                             RP_ALLOW_STDIN);
 150                 prv = key_load_private(filename, pass, NULL);
 151                 memset(pass, 0, strlen(pass));
 152                 xfree(pass);
 153         }
 154         return prv;
 155 }
 156
 157 #define SSH_COM_PUBLIC_BEGIN            "---- BEGIN SSH2 PUBLIC KEY ----"
 158 #define SSH_COM_PUBLIC_END              "---- END SSH2 PUBLIC KEY ----"
 159 #define SSH_COM_PRIVATE_BEGIN           "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----"
 160 #define SSH_COM_PRIVATE_KEY_MAGIC       0x3f6ff9eb
 161
 162 static void
 163 do_convert_to_ssh2(struct passwd *pw)
 164 {
 165         Key *k;
 166         u_int len;
 167         u_char *blob;
 168         struct stat st;
 169
 170         if (!have_identity)
 171                 ask_filename(pw, "Enter file in which the key is");
 172         if (stat(identity_file, &st) < 0) {
 173                 perror(identity_file);
 174                 exit(1);
 175         }
 176         if ((k = key_load_public(identity_file, NULL)) == NULL) {
 177                 if ((k = load_identity(identity_file)) == NULL) {
 178                         fprintf(stderr, "load failed\n");
 179                         exit(1);
 180                 }
 181         }
 182         if (k->type == KEY_RSA1) {
 183                 fprintf(stderr, "version 1 keys are not supported\n");
 184                 exit(1);
 185         }
 186         if (key_to_blob(k, &blob, &len) <= 0) {
 187                 fprintf(stderr, "key_to_blob failed\n");
 188                 exit(1);
 189         }
 190         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_BEGIN);
 191         fprintf(stdout,
 192             "Comment: \"%u-bit %s, converted from OpenSSH by %s@%s\"\n",
 193             key_size(k), key_type(k),
 194             pw->pw_name, hostname);
 195         dump_base64(stdout, blob, len);
 196         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_END);
 197         key_free(k);
 198         xfree(blob);
 199         exit(0);
 200 }
 201
 202 static void
 203 buffer_get_bignum_bits(Buffer *b, BIGNUM *value)
 204 {
 205         u_int bignum_bits = buffer_get_int(b);
 206         u_int bytes = (bignum_bits + 7) / 8;
 207
 208         if (buffer_len(b) < bytes)
 209                 fatal("buffer_get_bignum_bits: input buffer too small: "
 210                     "need %d have %d", bytes, buffer_len(b));
 211         BN_bin2bn(buffer_ptr(b), bytes, value);
 212         buffer_consume(b, bytes);
 213 }
 214
 215 static Key *
 216 do_convert_private_ssh2_from_blob(u_char *blob, u_int blen)
 217 {
 218         Buffer b;
 219         Key *key = NULL;
 220         char *type, *cipher;
 221         u_char *sig, data[] = "abcde12345";
 222         int magic, rlen, ktype, i1, i2, i3, i4;
 223         u_int slen;
 224         u_long e;
 225
 226         buffer_init(&b);
 227         buffer_append(&b, blob, blen);
 228
 229         magic  = buffer_get_int(&b);
 230         if (magic != SSH_COM_PRIVATE_KEY_MAGIC) {
 231                 error("bad magic 0x%x != 0x%x", magic, SSH_COM_PRIVATE_KEY_MAGIC);
 232                 buffer_free(&b);
 233                 return NULL;
 234         }
 235         i1 = buffer_get_int(&b);
 236         type   = buffer_get_string(&b, NULL);
 237         cipher = buffer_get_string(&b, NULL);
 238         i2 = buffer_get_int(&b);
 239         i3 = buffer_get_int(&b);
 240         i4 = buffer_get_int(&b);
 241         debug("ignore (%d %d %d %d)", i1,i2,i3,i4);
 242         if (strcmp(cipher, "none") != 0) {
 243                 error("unsupported cipher %s", cipher);
 244                 xfree(cipher);
 245                 buffer_free(&b);
 246                 xfree(type);
 247                 return NULL;
 248         }
 249         xfree(cipher);
 250
 251         if (strstr(type, "dsa")) {
 252                 ktype = KEY_DSA;
 253         } else if (strstr(type, "rsa")) {
 254                 ktype = KEY_RSA;
 255         } else {
 256                 buffer_free(&b);
 257                 xfree(type);
 258                 return NULL;
 259         }
 260         key = key_new_private(ktype);
 261         xfree(type);
 262
 263         switch (key->type) {
 264         case KEY_DSA:
 265                 buffer_get_bignum_bits(&b, key->dsa->p);
 266                 buffer_get_bignum_bits(&b, key->dsa->g);
 267                 buffer_get_bignum_bits(&b, key->dsa->q);
 268                 buffer_get_bignum_bits(&b, key->dsa->pub_key);
 269                 buffer_get_bignum_bits(&b, key->dsa->priv_key);
 270                 break;
 271         case KEY_RSA:
 272                 e  = buffer_get_char(&b);
 273                 debug("e %lx", e);
 274                 if (e < 30) {
 275                         e <<= 8;
 276                         e += buffer_get_char(&b);
 277                         debug("e %lx", e);
 278                         e <<= 8;
 279                         e += buffer_get_char(&b);
 280                         debug("e %lx", e);
 281                 }
 282                 if (!BN_set_word(key->rsa->e, e)) {
 283                         buffer_free(&b);
 284                         key_free(key);
 285                         return NULL;
 286                 }
 287                 buffer_get_bignum_bits(&b, key->rsa->d);
 288                 buffer_get_bignum_bits(&b, key->rsa->n);
 289                 buffer_get_bignum_bits(&b, key->rsa->iqmp);
 290                 buffer_get_bignum_bits(&b, key->rsa->q);
 291                 buffer_get_bignum_bits(&b, key->rsa->p);
 292                 rsa_generate_additional_parameters(key->rsa);
 293                 break;
 294         }
 295         rlen = buffer_len(&b);
 296         if (rlen != 0)
 297                 error("do_convert_private_ssh2_from_blob: "
 298                     "remaining bytes in key blob %d", rlen);
 299         buffer_free(&b);
 300
 301         /* try the key */
 302         key_sign(key, &sig, &slen, data, sizeof(data));
 303         key_verify(key, sig, slen, data, sizeof(data));
 304         xfree(sig);
 305         return key;
 306 }
 307
 308 static void
 309 do_convert_from_ssh2(struct passwd *pw)
 310 {
 311         Key *k;
 312         int blen;
 313         u_int len;
 314         char line[1024], *p;
 315         u_char blob[8096];
 316         char encoded[8096];
 317         struct stat st;
 318         int escaped = 0, private = 0, ok;
 319         FILE *fp;
 320
 321         if (!have_identity)
 322                 ask_filename(pw, "Enter file in which the key is");
 323         if (stat(identity_file, &st) < 0) {
 324                 perror(identity_file);
 325                 exit(1);
 326         }
 327         fp = fopen(identity_file, "r");
 328         if (fp == NULL) {
 329                 perror(identity_file);
 330                 exit(1);
 331         }
 332         encoded[0] = '\0';
 333         while (fgets(line, sizeof(line), fp)) {
 334                 if (!(p = strchr(line, '\n'))) {
 335                         fprintf(stderr, "input line too long.\n");
 336                         exit(1);
 337                 }
 338                 if (p > line && p[-1] == '\\')
 339                         escaped++;
 340                 if (strncmp(line, "----", 4) == 0 ||
 341                     strstr(line, ": ") != NULL) {
 342                         if (strstr(line, SSH_COM_PRIVATE_BEGIN) != NULL)
 343                                 private = 1;
 344                         if (strstr(line, " END ") != NULL) {
 345                                 break;
 346                         }
 347                         /* fprintf(stderr, "ignore: %s", line); */
 348                         continue;
 349                 }
 350                 if (escaped) {
 351                         escaped--;
 352                         /* fprintf(stderr, "escaped: %s", line); */
 353                         continue;
 354                 }
 355                 *p = '\0';
 356                 strlcat(encoded, line, sizeof(encoded));
 357         }
 358         len = strlen(encoded);
 359         if (((len % 4) == 3) &&
 360             (encoded[len-1] == '=') &&
 361             (encoded[len-2] == '=') &&
 362             (encoded[len-3] == '='))
 363                 encoded[len-3] = '\0';
 364         blen = uudecode(encoded, blob, sizeof(blob));
 365         if (blen < 0) {
 366                 fprintf(stderr, "uudecode failed.\n");
 367                 exit(1);
 368         }
 369         k = private ?
 370             do_convert_private_ssh2_from_blob(blob, blen) :
 371             key_from_blob(blob, blen);
 372         if (k == NULL) {
 373                 fprintf(stderr, "decode blob failed.\n");
 374                 exit(1);
 375         }
 376         ok = private ?
 377             (k->type == KEY_DSA ?
 378                  PEM_write_DSAPrivateKey(stdout, k->dsa, NULL, NULL, 0, NULL, NULL) :
 379                  PEM_write_RSAPrivateKey(stdout, k->rsa, NULL, NULL, 0, NULL, NULL)) :
 380             key_write(k, stdout);
 381         if (!ok) {
 382                 fprintf(stderr, "key write failed");
 383                 exit(1);
 384         }
 385         key_free(k);
 386         if (!private)
 387                 fprintf(stdout, "\n");
 388         fclose(fp);
 389         exit(0);
 390 }
 391
 392 static void
 393 do_print_public(struct passwd *pw)
 394 {
 395         Key *prv;
 396         struct stat st;
 397
 398         if (!have_identity)
 399                 ask_filename(pw, "Enter file in which the key is");
 400         if (stat(identity_file, &st) < 0) {
 401                 perror(identity_file);
 402                 exit(1);
 403         }
 404         prv = load_identity(identity_file);
 405         if (prv == NULL) {
 406                 fprintf(stderr, "load failed\n");
 407                 exit(1);
 408         }
 409         if (!key_write(prv, stdout))
 410                 fprintf(stderr, "key_write failed");
 411         key_free(prv);
 412         fprintf(stdout, "\n");
 413         exit(0);
 414 }
 415
 416 #ifdef SMARTCARD
 417 static void
 418 do_upload(struct passwd *pw, const char *sc_reader_id)
 419 {
 420         Key *prv = NULL;
 421         struct stat st;
 422         int ret;
 423
 424         if (!have_identity)
 425                 ask_filename(pw, "Enter file in which the key is");
 426         if (stat(identity_file, &st) < 0) {
 427                 perror(identity_file);
 428                 exit(1);
 429         }
 430         prv = load_identity(identity_file);
 431         if (prv == NULL) {
 432                 error("load failed");
 433                 exit(1);
 434         }
 435         ret = sc_put_key(prv, sc_reader_id);
 436         key_free(prv);
 437         if (ret < 0)
 438                 exit(1);
 439         logit("loading key done");
 440         exit(0);
 441 }
 442
 443 static void
 444 do_download(struct passwd *pw, const char *sc_reader_id)
 445 {
 446         Key **keys = NULL;
 447         int i;
 448
 449         keys = sc_get_keys(sc_reader_id, NULL);
 450         if (keys == NULL)
 451                 fatal("cannot read public key from smartcard");
 452         for (i = 0; keys[i]; i++) {
 453                 key_write(keys[i], stdout);
 454                 key_free(keys[i]);
 455                 fprintf(stdout, "\n");
 456         }
 457         xfree(keys);
 458         exit(0);
 459 }
 460 #endif /* SMARTCARD */
 461
 462 static void
 463 do_fingerprint(struct passwd *pw)
 464 {
 465         FILE *f;
 466         Key *public;
 467         char *comment = NULL, *cp, *ep, line[16*1024], *fp;
 468         int i, skip = 0, num = 1, invalid = 1;
 469         enum fp_rep rep;
 470         enum fp_type fptype;
 471         struct stat st;
 472
 473         fptype = print_bubblebabble ? SSH_FP_SHA1 : SSH_FP_MD5;
 474         rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_HEX;
 475
 476         if (!have_identity)
 477                 ask_filename(pw, "Enter file in which the key is");
 478         if (stat(identity_file, &st) < 0) {
 479                 perror(identity_file);
 480                 exit(1);
 481         }
 482         public = key_load_public(identity_file, &comment);
 483         if (public != NULL) {
 484                 fp = key_fingerprint(public, fptype, rep);
 485                 printf("%u %s %s\n", key_size(public), fp, comment);
 486                 key_free(public);
 487                 xfree(comment);
 488                 xfree(fp);
 489                 exit(0);
 490         }
 491         if (comment)
 492                 xfree(comment);
 493
 494         f = fopen(identity_file, "r");
 495         if (f != NULL) {
 496                 while (fgets(line, sizeof(line), f)) {
 497                         i = strlen(line) - 1;
 498                         if (line[i] != '\n') {
 499                                 error("line %d too long: %.40s...", num, line);
 500                                 skip = 1;
 501                                 continue;
 502                         }
 503                         num++;
 504                         if (skip) {
 505                                 skip = 0;
 506                                 continue;
 507                         }
 508                         line[i] = '\0';
 509
 510                         /* Skip leading whitespace, empty and comment lines. */
 511                         for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
 512                                 ;
 513                         if (!*cp || *cp == '\n' || *cp == '#')
 514                                 continue ;
 515                         i = strtol(cp, &ep, 10);
 516                         if (i == 0 || ep == NULL || (*ep != ' ' && *ep != '\t')) {
 517                                 int quoted = 0;
 518                                 comment = cp;
 519                                 for (; *cp && (quoted || (*cp != ' ' &&
 520                                     *cp != '\t')); cp++) {
 521                                         if (*cp == '\\' && cp[1] == '"')
 522                                                 cp++;   /* Skip both */
 523                                         else if (*cp == '"')
 524                                                 quoted = !quoted;
 525                                 }
 526                                 if (!*cp)
 527                                         continue;
 528                                 *cp++ = '\0';
 529                         }
 530                         ep = cp;
 531                         public = key_new(KEY_RSA1);
 532                         if (key_read(public, &cp) != 1) {
 533                                 cp = ep;
 534                                 key_free(public);
 535                                 public = key_new(KEY_UNSPEC);
 536                                 if (key_read(public, &cp) != 1) {
 537                                         key_free(public);
 538                                         continue;
 539                                 }
 540                         }
 541                         comment = *cp ? cp : comment;
 542                         fp = key_fingerprint(public, fptype, rep);
 543                         printf("%u %s %s\n", key_size(public), fp,
 544                             comment ? comment : "no comment");
 545                         xfree(fp);
 546                         key_free(public);
 547                         invalid = 0;
 548                 }
 549                 fclose(f);
 550         }
 551         if (invalid) {
 552                 printf("%s is not a public key file.\n", identity_file);
 553                 exit(1);
 554         }
 555         exit(0);
 556 }
 557
 558 static void
 559 print_host(FILE *f, char *name, Key *public, int hash)
 560 {
 561         if (hash && (name = host_hash(name, NULL, 0)) == NULL)
 562                 fatal("hash_host failed");
 563         fprintf(f, "%s ", name);
 564         if (!key_write(public, f))
 565                 fatal("key_write failed");
 566         fprintf(f, "\n");
 567 }
 568
 569 static void
 570 do_known_hosts(struct passwd *pw, const char *name)
 571 {
 572         FILE *in, *out = stdout;
 573         Key *public;
 574         char *cp, *cp2, *kp, *kp2;
 575         char line[16*1024], tmp[MAXPATHLEN], old[MAXPATHLEN];
 576         int c, i, skip = 0, inplace = 0, num = 0, invalid = 0, has_unhashed = 0;
 577
 578         if (!have_identity) {
 579                 cp = tilde_expand_filename(_PATH_SSH_USER_HOSTFILE, pw->pw_uid);
 580                 if (strlcpy(identity_file, cp, sizeof(identity_file)) >=
 581                     sizeof(identity_file))
 582                         fatal("Specified known hosts path too long");
 583                 xfree(cp);
 584                 have_identity = 1;
 585         }
 586         if ((in = fopen(identity_file, "r")) == NULL)
 587                 fatal("fopen: %s", strerror(errno));
 588
 589         /*
 590          * Find hosts goes to stdout, hash and deletions happen in-place
 591          * A corner case is ssh-keygen -HF foo, which should go to stdout
 592          */
 593         if (!find_host && (hash_hosts || delete_host)) {
 594                 if (strlcpy(tmp, identity_file, sizeof(tmp)) >= sizeof(tmp) ||
 595                     strlcat(tmp, ".XXXXXXXXXX", sizeof(tmp)) >= sizeof(tmp) ||
 596                     strlcpy(old, identity_file, sizeof(old)) >= sizeof(old) ||
 597                     strlcat(old, ".old", sizeof(old)) >= sizeof(old))
 598                         fatal("known_hosts path too long");
 599                 umask(077);
 600                 if ((c = mkstemp(tmp)) == -1)
 601                         fatal("mkstemp: %s", strerror(errno));
 602                 if ((out = fdopen(c, "w")) == NULL) {
 603                         c = errno;
 604                         unlink(tmp);
 605                         fatal("fdopen: %s", strerror(c));
 606                 }
 607                 inplace = 1;
 608         }
 609
 610         while (fgets(line, sizeof(line), in)) {
 611                 num++;
 612                 i = strlen(line) - 1;
 613                 if (line[i] != '\n') {
 614                         error("line %d too long: %.40s...", num, line);
 615                         skip = 1;
 616                         invalid = 1;
 617                         continue;
 618                 }
 619                 if (skip) {
 620                         skip = 0;
 621                         continue;
 622                 }
 623                 line[i] = '\0';
 624
 625                 /* Skip leading whitespace, empty and comment lines. */
 626                 for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
 627                         ;
 628                 if (!*cp || *cp == '\n' || *cp == '#') {
 629                         if (inplace)
 630                                 fprintf(out, "%s\n", cp);
 631                         continue;
 632                 }
 633                 /* Find the end of the host name portion. */
 634                 for (kp = cp; *kp && *kp != ' ' && *kp != '\t'; kp++)
 635                         ;
 636                 if (*kp == '\0' || *(kp + 1) == '\0') {
 637                         error("line %d missing key: %.40s...",
 638                             num, line);
 639                         invalid = 1;
 640                         continue;
 641                 }
 642                 *kp++ = '\0';
 643                 kp2 = kp;
 644
 645                 public = key_new(KEY_RSA1);
 646                 if (key_read(public, &kp) != 1) {
 647                         kp = kp2;
 648                         key_free(public);
 649                         public = key_new(KEY_UNSPEC);
 650                         if (key_read(public, &kp) != 1) {
 651                                 error("line %d invalid key: %.40s...",
 652                                     num, line);
 653                                 key_free(public);
 654                                 invalid = 1;
 655                                 continue;
 656                         }
 657                 }
 658
 659                 if (*cp == HASH_DELIM) {
 660                         if (find_host || delete_host) {
 661                                 cp2 = host_hash(name, cp, strlen(cp));
 662                                 if (cp2 == NULL) {
 663                                         error("line %d: invalid hashed "
 664                                             "name: %.64s...", num, line);
 665                                         invalid = 1;
 666                                         continue;
 667                                 }
 668                                 c = (strcmp(cp2, cp) == 0);
 669                                 if (find_host && c) {
 670                                         printf("# Host %s found: "
 671                                             "line %d type %s\n", name,
 672                                             num, key_type(public));
 673                                         print_host(out, cp, public, 0);
 674                                 }
 675                                 if (delete_host && !c)
 676                                         print_host(out, cp, public, 0);
 677                         } else if (hash_hosts)
 678                                 print_host(out, cp, public, 0);
 679                 } else {
 680                         if (find_host || delete_host) {
 681                                 c = (match_hostname(name, cp,
 682                                     strlen(cp)) == 1);
 683                                 if (find_host && c) {
 684                                         printf("# Host %s found: "
 685                                             "line %d type %s\n", name,
 686                                             num, key_type(public));
 687                                         print_host(out, cp, public, hash_hosts);
 688                                 }
 689                                 if (delete_host && !c)
 690                                         print_host(out, cp, public, 0);
 691                         } else if (hash_hosts) {
 692                                 for (cp2 = strsep(&cp, ",");
 693                                     cp2 != NULL && *cp2 != '\0';
 694                                     cp2 = strsep(&cp, ",")) {
 695                                         if (strcspn(cp2, "*?!") != strlen(cp2))
 696                                                 fprintf(stderr, "Warning: "
 697                                                     "ignoring host name with "
 698                                                     "metacharacters: %.64s\n",
 699                                                     cp2);
 700                                         else
 701                                                 print_host(out, cp2, public, 1);
 702                                 }
 703                                 has_unhashed = 1;
 704                         }
 705                 }
 706                 key_free(public);
 707         }
 708         fclose(in);
 709
 710         if (invalid) {
 711                 fprintf(stderr, "%s is not a valid known_host file.\n",
 712                     identity_file);
 713                 if (inplace) {
 714                         fprintf(stderr, "Not replacing existing known_hosts "
 715                             "file because of errors\n");
 716                         fclose(out);
 717                         unlink(tmp);
 718                 }
 719                 exit(1);
 720         }
 721
 722         if (inplace) {
 723                 fclose(out);
 724
 725                 /* Backup existing file */
 726                 if (unlink(old) == -1 && errno != ENOENT)
 727                         fatal("unlink %.100s: %s", old, strerror(errno));
 728                 if (link(identity_file, old) == -1)
 729                         fatal("link %.100s to %.100s: %s", identity_file, old,
 730                             strerror(errno));
 731                 /* Move new one into place */
 732                 if (rename(tmp, identity_file) == -1) {
 733                         error("rename\"%s\" to \"%s\": %s", tmp, identity_file,
 734                             strerror(errno));
 735                         unlink(tmp);
 736                         unlink(old);
 737                         exit(1);
 738                 }
 739
 740                 fprintf(stderr, "%s updated.\n", identity_file);
 741                 fprintf(stderr, "Original contents retained as %s\n", old);
 742                 if (has_unhashed) {
 743                         fprintf(stderr, "WARNING: %s contains unhashed "
 744                             "entries\n", old);
 745                         fprintf(stderr, "Delete this file to ensure privacy "
 746                             "of hostnames\n");
 747                 }
 748         }
 749
 750         exit(0);
 751 }
 752
 753 /*
 754  * Perform changing a passphrase.  The argument is the passwd structure
 755  * for the current user.
 756  */
 757 static void
 758 do_change_passphrase(struct passwd *pw)
 759 {
 760         char *comment;
 761         char *old_passphrase, *passphrase1, *passphrase2;
 762         struct stat st;
 763         Key *private;
 764
 765         if (!have_identity)
 766                 ask_filename(pw, "Enter file in which the key is");
 767         if (stat(identity_file, &st) < 0) {
 768                 perror(identity_file);
 769                 exit(1);
 770         }
 771         /* Try to load the file with empty passphrase. */
 772         private = key_load_private(identity_file, "", &comment);
 773         if (private == NULL) {
 774                 if (identity_passphrase)
 775                         old_passphrase = xstrdup(identity_passphrase);
 776                 else
 777                         old_passphrase =
 778                             read_passphrase("Enter old passphrase: ",
 779                             RP_ALLOW_STDIN);
 780                 private = key_load_private(identity_file, old_passphrase,
 781                     &comment);
 782                 memset(old_passphrase, 0, strlen(old_passphrase));
 783                 xfree(old_passphrase);
 784                 if (private == NULL) {
 785                         printf("Bad passphrase.\n");
 786                         exit(1);
 787                 }
 788         }
 789         printf("Key has comment '%s'\n", comment);
 790
 791         /* Ask the new passphrase (twice). */
 792         if (identity_new_passphrase) {
 793                 passphrase1 = xstrdup(identity_new_passphrase);
 794                 passphrase2 = NULL;
 795         } else {
 796                 passphrase1 =
 797                         read_passphrase("Enter new passphrase (empty for no "
 798                             "passphrase): ", RP_ALLOW_STDIN);
 799                 passphrase2 = read_passphrase("Enter same passphrase again: ",
 800                     RP_ALLOW_STDIN);
 801
 802                 /* Verify that they are the same. */
 803                 if (strcmp(passphrase1, passphrase2) != 0) {
 804                         memset(passphrase1, 0, strlen(passphrase1));
 805                         memset(passphrase2, 0, strlen(passphrase2));
 806                         xfree(passphrase1);
 807                         xfree(passphrase2);
 808                         printf("Pass phrases do not match.  Try again.\n");
 809                         exit(1);
 810                 }
 811                 /* Destroy the other copy. */
 812                 memset(passphrase2, 0, strlen(passphrase2));
 813                 xfree(passphrase2);
 814         }
 815
 816         /* Save the file using the new passphrase. */
 817         if (!key_save_private(private, identity_file, passphrase1, comment)) {
 818                 printf("Saving the key failed: %s.\n", identity_file);
 819                 memset(passphrase1, 0, strlen(passphrase1));
 820                 xfree(passphrase1);
 821                 key_free(private);
 822                 xfree(comment);
 823                 exit(1);
 824         }
 825         /* Destroy the passphrase and the copy of the key in memory. */
 826         memset(passphrase1, 0, strlen(passphrase1));
 827         xfree(passphrase1);
 828         key_free(private);               /* Destroys contents */
 829         xfree(comment);
 830
 831         printf("Your identification has been saved with the new passphrase.\n");
 832         exit(0);
 833 }
 834
 835 /*
 836  * Print the SSHFP RR.
 837  */
 838 static void
 839 do_print_resource_record(struct passwd *pw, char *hname)
 840 {
 841         Key *public;
 842         char *comment = NULL;
 843         struct stat st;
 844
 845         if (!have_identity)
 846                 ask_filename(pw, "Enter file in which the key is");
 847         if (stat(identity_file, &st) < 0) {
 848                 perror(identity_file);
 849                 exit(1);
 850         }
 851         public = key_load_public(identity_file, &comment);
 852         if (public != NULL) {
 853                 export_dns_rr(hname, public, stdout, print_generic);
 854                 key_free(public);
 855                 xfree(comment);
 856                 exit(0);
 857         }
 858         if (comment)
 859                 xfree(comment);
 860
 861         printf("failed to read v2 public key from %s.\n", identity_file);
 862         exit(1);
 863 }
 864
 865 /*
 866  * Change the comment of a private key file.
 867  */
 868 static void
 869 do_change_comment(struct passwd *pw)
 870 {
 871         char new_comment[1024], *comment, *passphrase;
 872         Key *private;
 873         Key *public;
 874         struct stat st;
 875         FILE *f;
 876         int fd;
 877
 878         if (!have_identity)
 879                 ask_filename(pw, "Enter file in which the key is");
 880         if (stat(identity_file, &st) < 0) {
 881                 perror(identity_file);
 882                 exit(1);
 883         }
 884         private = key_load_private(identity_file, "", &comment);
 885         if (private == NULL) {
 886                 if (identity_passphrase)
 887                         passphrase = xstrdup(identity_passphrase);
 888                 else if (identity_new_passphrase)
 889                         passphrase = xstrdup(identity_new_passphrase);
 890                 else
 891                         passphrase = read_passphrase("Enter passphrase: ",
 892                             RP_ALLOW_STDIN);
 893                 /* Try to load using the passphrase. */
 894                 private = key_load_private(identity_file, passphrase, &comment);
 895                 if (private == NULL) {
 896                         memset(passphrase, 0, strlen(passphrase));
 897                         xfree(passphrase);
 898                         printf("Bad passphrase.\n");
 899                         exit(1);
 900                 }
 901         } else {
 902                 passphrase = xstrdup("");
 903         }
 904         if (private->type != KEY_RSA1) {
 905                 fprintf(stderr, "Comments are only supported for RSA1 keys.\n");
 906                 key_free(private);
 907                 exit(1);
 908         }
 909         printf("Key now has comment '%s'\n", comment);
 910
 911         if (identity_comment) {
 912                 strlcpy(new_comment, identity_comment, sizeof(new_comment));
 913         } else {
 914                 printf("Enter new comment: ");
 915                 fflush(stdout);
 916                 if (!fgets(new_comment, sizeof(new_comment), stdin)) {
 917                         memset(passphrase, 0, strlen(passphrase));
 918                         key_free(private);
 919                         exit(1);
 920                 }
 921                 if (strchr(new_comment, '\n'))
 922                         *strchr(new_comment, '\n') = 0;
 923         }
 924
 925         /* Save the file using the new passphrase. */
 926         if (!key_save_private(private, identity_file, passphrase, new_comment)) {
 927                 printf("Saving the key failed: %s.\n", identity_file);
 928                 memset(passphrase, 0, strlen(passphrase));
 929                 xfree(passphrase);
 930                 key_free(private);
 931                 xfree(comment);
 932                 exit(1);
 933         }
 934         memset(passphrase, 0, strlen(passphrase));
 935         xfree(passphrase);
 936         public = key_from_private(private);
 937         key_free(private);
 938
 939         strlcat(identity_file, ".pub", sizeof(identity_file));
 940         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 941         if (fd == -1) {
 942                 printf("Could not save your public key in %s\n", identity_file);
 943                 exit(1);
 944         }
 945         f = fdopen(fd, "w");
 946         if (f == NULL) {
 947                 printf("fdopen %s failed", identity_file);
 948                 exit(1);
 949         }
 950         if (!key_write(public, f))
 951                 fprintf(stderr, "write key failed");
 952         key_free(public);
 953         fprintf(f, " %s\n", new_comment);
 954         fclose(f);
 955
 956         xfree(comment);
 957
 958         printf("The comment in your key file has been changed.\n");
 959         exit(0);
 960 }
 961
 962 static void
 963 usage(void)
 964 {
 965         fprintf(stderr, "Usage: %s [options]\n", __progname);
 966         fprintf(stderr, "Options:\n");
 967         fprintf(stderr, "  -a trials   Number of trials for screening DH-GEX moduli.\n");
 968         fprintf(stderr, "  -B          Show bubblebabble digest of key file.\n");
 969         fprintf(stderr, "  -b bits     Number of bits in the key to create.\n");
 970         fprintf(stderr, "  -C comment  Provide new comment.\n");
 971         fprintf(stderr, "  -c          Change comment in private and public key files.\n");
 972 #ifdef SMARTCARD
 973         fprintf(stderr, "  -D reader   Download public key from smartcard.\n");
 974 #endif /* SMARTCARD */
 975         fprintf(stderr, "  -e          Convert OpenSSH to IETF SECSH key file.\n");
 976         fprintf(stderr, "  -F hostname Find hostname in known hosts file.\n");
 977         fprintf(stderr, "  -f filename Filename of the key file.\n");
 978         fprintf(stderr, "  -G file     Generate candidates for DH-GEX moduli.\n");
 979         fprintf(stderr, "  -g          Use generic DNS resource record format.\n");
 980         fprintf(stderr, "  -H          Hash names in known_hosts file.\n");
 981         fprintf(stderr, "  -i          Convert IETF SECSH to OpenSSH key file.\n");
 982         fprintf(stderr, "  -l          Show fingerprint of key file.\n");
 983         fprintf(stderr, "  -M memory   Amount of memory (MB) to use for generating DH-GEX moduli.\n");
 984         fprintf(stderr, "  -N phrase   Provide new passphrase.\n");
 985         fprintf(stderr, "  -P phrase   Provide old passphrase.\n");
 986         fprintf(stderr, "  -p          Change passphrase of private key file.\n");
 987         fprintf(stderr, "  -q          Quiet.\n");
 988         fprintf(stderr, "  -R hostname Remove host from known_hosts file.\n");
 989         fprintf(stderr, "  -r hostname Print DNS resource record.\n");
 990         fprintf(stderr, "  -S start    Start point (hex) for generating DH-GEX moduli.\n");
 991         fprintf(stderr, "  -T file     Screen candidates for DH-GEX moduli.\n");
 992         fprintf(stderr, "  -t type     Specify type of key to create.\n");
 993 #ifdef SMARTCARD
 994         fprintf(stderr, "  -U reader   Upload private key to smartcard.\n");
 995 #endif /* SMARTCARD */
 996         fprintf(stderr, "  -v          Verbose.\n");
 997         fprintf(stderr, "  -W gen      Generator to use for generating DH-GEX moduli.\n");
 998         fprintf(stderr, "  -y          Read private key file and print public key.\n");
 999
1000         exit(1);
1001 }
1002
1003 /*
1004  * Main program for key management.
1005  */
1006 int
1007 main(int ac, char **av)
1008 {
1009         char dotsshdir[MAXPATHLEN], comment[1024], *passphrase1, *passphrase2;
1010         char out_file[MAXPATHLEN], *reader_id = NULL;
1011         char *rr_hostname = NULL;
1012         Key *private, *public;
1013         struct passwd *pw;
1014         struct stat st;
1015         int opt, type, fd, download = 0;
1016         u_int32_t memory = 0, generator_wanted = 0, trials = 100;
1017         int do_gen_candidates = 0, do_screen_candidates = 0;
1018         int log_level = SYSLOG_LEVEL_INFO;
1019         BIGNUM *start = NULL;
1020         FILE *f;
1021         const char *errstr;
1022
1023         extern int optind;
1024         extern char *optarg;
1025
1026         /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
1027         sanitise_stdfd();
1028
1029         __progname = ssh_get_progname(av[0]);
1030
1031         SSLeay_add_all_algorithms();
1032         log_init(av[0], SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_USER, 1);
1033
1034         init_rng();
1035         seed_rng();
1036
1037         /* we need this for the home * directory.  */
1038         pw = getpwuid(getuid());
1039         if (!pw) {
1040                 printf("You don't exist, go away!\n");
1041                 exit(1);
1042         }
1043         if (gethostname(hostname, sizeof(hostname)) < 0) {
1044                 perror("gethostname");
1045                 exit(1);
1046         }
1047
1048         while ((opt = getopt(ac, av,
1049             "degiqpclBHvxXyF:b:f:t:U:D:P:N:C:r:g:R:T:G:M:S:a:W:")) != -1) {
1050                 switch (opt) {
1051                 case 'b':
1052                         bits = strtonum(optarg, 768, 32768, &errstr);
1053                         if (errstr)
1054                                 fatal("Bits has bad value %s (%s)",
1055                                         optarg, errstr);
1056                         break;
1057                 case 'F':
1058                         find_host = 1;
1059                         rr_hostname = optarg;
1060                         break;
1061                 case 'H':
1062                         hash_hosts = 1;
1063                         break;
1064                 case 'R':
1065                         delete_host = 1;
1066                         rr_hostname = optarg;
1067                         break;
1068                 case 'l':
1069                         print_fingerprint = 1;
1070                         break;
1071                 case 'B':
1072                         print_bubblebabble = 1;
1073                         break;
1074                 case 'p':
1075                         change_passphrase = 1;
1076                         break;
1077                 case 'c':
1078                         change_comment = 1;
1079                         break;
1080                 case 'f':
1081                         if (strlcpy(identity_file, optarg, sizeof(identity_file)) >=
1082                             sizeof(identity_file))
1083                                 fatal("Identity filename too long");
1084                         have_identity = 1;
1085                         break;
1086                 case 'g':
1087                         print_generic = 1;
1088                         break;
1089                 case 'P':
1090                         identity_passphrase = optarg;
1091                         break;
1092                 case 'N':
1093                         identity_new_passphrase = optarg;
1094                         break;
1095                 case 'C':
1096                         identity_comment = optarg;
1097                         break;
1098                 case 'q':
1099                         quiet = 1;
1100                         break;
1101                 case 'e':
1102                 case 'x':
1103                         /* export key */
1104                         convert_to_ssh2 = 1;
1105                         break;
1106                 case 'i':
1107                 case 'X':
1108                         /* import key */
1109                         convert_from_ssh2 = 1;
1110                         break;
1111                 case 'y':
1112                         print_public = 1;
1113                         break;
1114                 case 'd':
1115                         key_type_name = "dsa";
1116                         break;
1117                 case 't':
1118                         key_type_name = optarg;
1119                         break;
1120                 case 'D':
1121                         download = 1;
1122                 case 'U':
1123                         reader_id = optarg;
1124                         break;
1125                 case 'v':
1126                         if (log_level == SYSLOG_LEVEL_INFO)
1127                                 log_level = SYSLOG_LEVEL_DEBUG1;
1128                         else {
1129                                 if (log_level >= SYSLOG_LEVEL_DEBUG1 &&
1130                                     log_level < SYSLOG_LEVEL_DEBUG3)
1131                                         log_level++;
1132                         }
1133                         break;
1134                 case 'r':
1135                         rr_hostname = optarg;
1136                         break;
1137                 case 'W':
1138                         generator_wanted = strtonum(optarg, 1, UINT_MAX, &errstr);
1139                         if (errstr)
1140                                 fatal("Desired generator has bad value: %s (%s)",
1141                                         optarg, errstr);
1142                         break;
1143                 case 'a':
1144                         trials = strtonum(optarg, 1, UINT_MAX, &errstr);
1145                         if (errstr)
1146                                 fatal("Invalid number of trials: %s (%s)",
1147                                         optarg, errstr);
1148                         break;
1149                 case 'M':
1150                         memory = strtonum(optarg, 1, UINT_MAX, &errstr);
1151                         if (errstr) {
1152                                 fatal("Memory limit is %s: %s", errstr, optarg);
1153                         }
1154                         break;
1155                 case 'G':
1156                         do_gen_candidates = 1;
1157                         if (strlcpy(out_file, optarg, sizeof(out_file)) >=
1158                             sizeof(out_file))
1159                                 fatal("Output filename too long");
1160                         break;
1161                 case 'T':
1162                         do_screen_candidates = 1;
1163                         if (strlcpy(out_file, optarg, sizeof(out_file)) >=
1164                             sizeof(out_file))
1165                                 fatal("Output filename too long");
1166                         break;
1167                 case 'S':
1168                         /* XXX - also compare length against bits */
1169                         if (BN_hex2bn(&start, optarg) == 0)
1170                                 fatal("Invalid start point.");
1171                         break;
1172                 case '?':
1173                 default:
1174                         usage();
1175                 }
1176         }
1177
1178         /* reinit */
1179         log_init(av[0], log_level, SYSLOG_FACILITY_USER, 1);
1180
1181         if (optind < ac) {
1182                 printf("Too many arguments.\n");
1183                 usage();
1184         }
1185         if (change_passphrase && change_comment) {
1186                 printf("Can only have one of -p and -c.\n");
1187                 usage();
1188         }
1189         if (delete_host || hash_hosts || find_host)
1190                 do_known_hosts(pw, rr_hostname);
1191         if (print_fingerprint || print_bubblebabble)
1192                 do_fingerprint(pw);
1193         if (change_passphrase)
1194                 do_change_passphrase(pw);
1195         if (change_comment)
1196                 do_change_comment(pw);
1197         if (convert_to_ssh2)
1198                 do_convert_to_ssh2(pw);
1199         if (convert_from_ssh2)
1200                 do_convert_from_ssh2(pw);
1201         if (print_public)
1202                 do_print_public(pw);
1203         if (rr_hostname != NULL) {
1204                 do_print_resource_record(pw, rr_hostname);
1205         }
1206         if (reader_id != NULL) {
1207 #ifdef SMARTCARD
1208                 if (download)
1209                         do_download(pw, reader_id);
1210                 else
1211                         do_upload(pw, reader_id);
1212 #else /* SMARTCARD */
1213                 fatal("no support for smartcards.");
1214 #endif /* SMARTCARD */
1215         }
1216
1217         if (do_gen_candidates) {
1218                 FILE *out = fopen(out_file, "w");
1219
1220                 if (out == NULL) {
1221                         error("Couldn't open modulus candidate file \"%s\": %s",
1222                             out_file, strerror(errno));
1223                         return (1);
1224                 }
1225                 if (bits == 0)
1226                         bits = DEFAULT_BITS;
1227                 if (gen_candidates(out, memory, bits, start) != 0)
1228                         fatal("modulus candidate generation failed");
1229
1230                 return (0);
1231         }
1232
1233         if (do_screen_candidates) {
1234                 FILE *in;
1235                 FILE *out = fopen(out_file, "w");
1236
1237                 if (have_identity && strcmp(identity_file, "-") != 0) {
1238                         if ((in = fopen(identity_file, "r")) == NULL) {
1239                                 fatal("Couldn't open modulus candidate "
1240                                     "file \"%s\": %s", identity_file,
1241                                     strerror(errno));
1242                         }
1243                 } else
1244                         in = stdin;
1245
1246                 if (out == NULL) {
1247                         fatal("Couldn't open moduli file \"%s\": %s",
1248                             out_file, strerror(errno));
1249                 }
1250                 if (prime_test(in, out, trials, generator_wanted) != 0)
1251                         fatal("modulus screening failed");
1252                 return (0);
1253         }
1254
1255         arc4random_stir();
1256
1257         if (key_type_name == NULL)
1258                 key_type_name = "rsa";
1259
1260         type = key_type_from_name(key_type_name);
1261         if (type == KEY_UNSPEC) {
1262                 fprintf(stderr, "unknown key type %s\n", key_type_name);
1263                 exit(1);
1264         }
1265         if (bits == 0)
1266                 bits = (type == KEY_DSA) ? DEFAULT_BITS_DSA : DEFAULT_BITS;
1267         if (type == KEY_DSA && bits != 1024)
1268                 fatal("DSA keys must be 1024 bits");
1269         if (!quiet)
1270                 printf("Generating public/private %s key pair.\n", key_type_name);
1271         private = key_generate(type, bits);
1272         if (private == NULL) {
1273                 fprintf(stderr, "key_generate failed");
1274                 exit(1);
1275         }
1276         public  = key_from_private(private);
1277
1278         if (!have_identity)
1279                 ask_filename(pw, "Enter file in which to save the key");
1280
1281         /* Create ~/.ssh directory if it doesn't already exist. */
1282         snprintf(dotsshdir, sizeof dotsshdir, "%s/%s", pw->pw_dir, _PATH_SSH_USER_DIR);
1283         if (strstr(identity_file, dotsshdir) != NULL &&
1284             stat(dotsshdir, &st) < 0) {
1285                 if (mkdir(dotsshdir, 0700) < 0)
1286                         error("Could not create directory '%s'.", dotsshdir);
1287                 else if (!quiet)
1288                         printf("Created directory '%s'.\n", dotsshdir);
1289         }
1290         /* If the file already exists, ask the user to confirm. */
1291         if (stat(identity_file, &st) >= 0) {
1292                 char yesno[3];
1293                 printf("%s already exists.\n", identity_file);
1294                 printf("Overwrite (y/n)? ");
1295                 fflush(stdout);
1296                 if (fgets(yesno, sizeof(yesno), stdin) == NULL)
1297                         exit(1);
1298                 if (yesno[0] != 'y' && yesno[0] != 'Y')
1299                         exit(1);
1300         }
1301         /* Ask for a passphrase (twice). */
1302         if (identity_passphrase)
1303                 passphrase1 = xstrdup(identity_passphrase);
1304         else if (identity_new_passphrase)
1305                 passphrase1 = xstrdup(identity_new_passphrase);
1306         else {
1307 passphrase_again:
1308                 passphrase1 =
1309                         read_passphrase("Enter passphrase (empty for no "
1310                             "passphrase): ", RP_ALLOW_STDIN);
1311                 passphrase2 = read_passphrase("Enter same passphrase again: ",
1312                     RP_ALLOW_STDIN);
1313                 if (strcmp(passphrase1, passphrase2) != 0) {
1314                         /*
1315                          * The passphrases do not match.  Clear them and
1316                          * retry.
1317                          */
1318                         memset(passphrase1, 0, strlen(passphrase1));
1319                         memset(passphrase2, 0, strlen(passphrase2));
1320                         xfree(passphrase1);
1321                         xfree(passphrase2);
1322                         printf("Passphrases do not match.  Try again.\n");
1323                         goto passphrase_again;
1324                 }
1325                 /* Clear the other copy of the passphrase. */
1326                 memset(passphrase2, 0, strlen(passphrase2));
1327                 xfree(passphrase2);
1328         }
1329
1330         if (identity_comment) {
1331                 strlcpy(comment, identity_comment, sizeof(comment));
1332         } else {
1333                 /* Create default commend field for the passphrase. */
1334                 snprintf(comment, sizeof comment, "%s@%s", pw->pw_name, hostname);
1335         }
1336
1337         /* Save the key with the given passphrase and comment. */
1338         if (!key_save_private(private, identity_file, passphrase1, comment)) {
1339                 printf("Saving the key failed: %s.\n", identity_file);
1340                 memset(passphrase1, 0, strlen(passphrase1));
1341                 xfree(passphrase1);
1342                 exit(1);
1343         }
1344         /* Clear the passphrase. */
1345         memset(passphrase1, 0, strlen(passphrase1));
1346         xfree(passphrase1);
1347
1348         /* Clear the private key and the random number generator. */
1349         key_free(private);
1350         arc4random_stir();
1351
1352         if (!quiet)
1353                 printf("Your identification has been saved in %s.\n", identity_file);
1354
1355         strlcat(identity_file, ".pub", sizeof(identity_file));
1356         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
1357         if (fd == -1) {
1358                 printf("Could not save your public key in %s\n", identity_file);
1359                 exit(1);
1360         }
1361         f = fdopen(fd, "w");
1362         if (f == NULL) {
1363                 printf("fdopen %s failed", identity_file);
1364                 exit(1);
1365         }
1366         if (!key_write(public, f))
1367                 fprintf(stderr, "write key failed");
1368         fprintf(f, " %s\n", comment);
1369         fclose(f);
1370
1371         if (!quiet) {
1372                 char *fp = key_fingerprint(public, SSH_FP_MD5, SSH_FP_HEX);
1373                 printf("Your public key has been saved in %s.\n",
1374                     identity_file);
1375                 printf("The key fingerprint is:\n");
1376                 printf("%s %s\n", fp, comment);
1377                 xfree(fp);
1378         }
1379
1380         key_free(public);
1381         exit(0);
1382 }