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 1.61 2001/05/25 14:37:32 markus 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 "readpass.h"
  30
  31 /* Number of bits in the RSA/DSA key.  This value can be changed on the command line. */
  32 int bits = 1024;
  33
  34 /*
  35  * Flag indicating that we just want to change the passphrase.  This can be
  36  * set on the command line.
  37  */
  38 int change_passphrase = 0;
  39
  40 /*
  41  * Flag indicating that we just want to change the comment.  This can be set
  42  * on the command line.
  43  */
  44 int change_comment = 0;
  45
  46 int quiet = 0;
  47
  48 /* Flag indicating that we just want to see the key fingerprint */
  49 int print_fingerprint = 0;
  50 int print_bubblebabble = 0;
  51
  52 /* The identity file name, given on the command line or entered by the user. */
  53 char identity_file[1024];
  54 int have_identity = 0;
  55
  56 /* This is set to the passphrase if given on the command line. */
  57 char *identity_passphrase = NULL;
  58
  59 /* This is set to the new passphrase if given on the command line. */
  60 char *identity_new_passphrase = NULL;
  61
  62 /* This is set to the new comment if given on the command line. */
  63 char *identity_comment = NULL;
  64
  65 /* Dump public key file in format used by real and the original SSH 2 */
  66 int convert_to_ssh2 = 0;
  67 int convert_from_ssh2 = 0;
  68 int print_public = 0;
  69
  70 /* default to RSA for SSH-1 */
  71 char *key_type_name = "rsa1";
  72
  73 /* argv0 */
  74 #ifdef HAVE___PROGNAME
  75 extern char *__progname;
  76 #else
  77 char *__progname;
  78 #endif
  79
  80 char hostname[MAXHOSTNAMELEN];
  81
  82 void
  83 ask_filename(struct passwd *pw, const char *prompt)
  84 {
  85         char buf[1024];
  86         char *name = NULL;
  87
  88         switch (key_type_from_name(key_type_name)) {
  89         case KEY_RSA1:
  90                 name = _PATH_SSH_CLIENT_IDENTITY;
  91                 break;
  92         case KEY_DSA:
  93                 name = _PATH_SSH_CLIENT_ID_DSA;
  94                 break;
  95         case KEY_RSA:
  96                 name = _PATH_SSH_CLIENT_ID_RSA;
  97                 break;
  98         default:
  99                 fprintf(stderr, "bad key type");
 100                 exit(1);
 101                 break;
 102         }
 103         snprintf(identity_file, sizeof(identity_file), "%s/%s", pw->pw_dir, name);
 104         fprintf(stderr, "%s (%s): ", prompt, identity_file);
 105         fflush(stderr);
 106         if (fgets(buf, sizeof(buf), stdin) == NULL)
 107                 exit(1);
 108         if (strchr(buf, '\n'))
 109                 *strchr(buf, '\n') = 0;
 110         if (strcmp(buf, "") != 0)
 111                 strlcpy(identity_file, buf, sizeof(identity_file));
 112         have_identity = 1;
 113 }
 114
 115 Key *
 116 load_identity(char *filename)
 117 {
 118         char *pass;
 119         Key *prv;
 120
 121         prv = key_load_private(filename, "", NULL);
 122         if (prv == NULL) {
 123                 if (identity_passphrase)
 124                         pass = xstrdup(identity_passphrase);
 125                 else
 126                         pass = read_passphrase("Enter passphrase: ", 1);
 127                 prv = key_load_private(filename, pass, NULL);
 128                 memset(pass, 0, strlen(pass));
 129                 xfree(pass);
 130         }
 131         return prv;
 132 }
 133
 134 #define SSH_COM_PUBLIC_BEGIN            "---- BEGIN SSH2 PUBLIC KEY ----"
 135 #define SSH_COM_PUBLIC_END              "---- END SSH2 PUBLIC KEY ----"
 136 #define SSH_COM_PRIVATE_BEGIN           "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----"
 137 #define SSH_COM_PRIVATE_KEY_MAGIC       0x3f6ff9eb
 138
 139 void
 140 do_convert_to_ssh2(struct passwd *pw)
 141 {
 142         Key *k;
 143         int len;
 144         u_char *blob;
 145         struct stat st;
 146
 147         if (!have_identity)
 148                 ask_filename(pw, "Enter file in which the key is");
 149         if (stat(identity_file, &st) < 0) {
 150                 perror(identity_file);
 151                 exit(1);
 152         }
 153         if ((k = key_load_public(identity_file, NULL)) == NULL) {
 154                 if ((k = load_identity(identity_file)) == NULL) {
 155                         fprintf(stderr, "load failed\n");
 156                         exit(1);
 157                 }
 158         }
 159         key_to_blob(k, &blob, &len);
 160         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_BEGIN);
 161         fprintf(stdout,
 162             "Comment: \"%d-bit %s, converted from OpenSSH by %s@%s\"\n",
 163             key_size(k), key_type(k),
 164             pw->pw_name, hostname);
 165         dump_base64(stdout, blob, len);
 166         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_END);
 167         key_free(k);
 168         xfree(blob);
 169         exit(0);
 170 }
 171
 172 void
 173 buffer_get_bignum_bits(Buffer *b, BIGNUM *value)
 174 {
 175         int bits = buffer_get_int(b);
 176         int bytes = (bits + 7) / 8;
 177
 178         if (buffer_len(b) < bytes)
 179                 fatal("buffer_get_bignum_bits: input buffer too small: "
 180                     "need %d have %d", bytes, buffer_len(b));
 181         BN_bin2bn((u_char *)buffer_ptr(b), bytes, value);
 182         buffer_consume(b, bytes);
 183 }
 184
 185 Key *
 186 do_convert_private_ssh2_from_blob(char *blob, int blen)
 187 {
 188         Buffer b;
 189         Key *key = NULL;
 190         int ignore, magic, rlen, ktype;
 191         char *type, *cipher;
 192
 193         buffer_init(&b);
 194         buffer_append(&b, blob, blen);
 195
 196         magic  = buffer_get_int(&b);
 197         if (magic != SSH_COM_PRIVATE_KEY_MAGIC) {
 198                 error("bad magic 0x%x != 0x%x", magic, SSH_COM_PRIVATE_KEY_MAGIC);
 199                 buffer_free(&b);
 200                 return NULL;
 201         }
 202         ignore = buffer_get_int(&b);
 203         type   = buffer_get_string(&b, NULL);
 204         cipher = buffer_get_string(&b, NULL);
 205         ignore = buffer_get_int(&b);
 206         ignore = buffer_get_int(&b);
 207         ignore = buffer_get_int(&b);
 208
 209         if (strcmp(cipher, "none") != 0) {
 210                 error("unsupported cipher %s", cipher);
 211                 xfree(cipher);
 212                 buffer_free(&b);
 213                 xfree(type);
 214                 return NULL;
 215         }
 216         xfree(cipher);
 217
 218         if (strstr(type, "dsa")) {
 219                 ktype = KEY_DSA;
 220         } else if (strstr(type, "rsa")) {
 221                 ktype = KEY_RSA;
 222         } else {
 223                 xfree(type);
 224                 return NULL;
 225         }
 226         key = key_new_private(ktype);
 227         xfree(type);
 228
 229         switch (key->type) {
 230         case KEY_DSA:
 231                 buffer_get_bignum_bits(&b, key->dsa->p);
 232                 buffer_get_bignum_bits(&b, key->dsa->g);
 233                 buffer_get_bignum_bits(&b, key->dsa->q);
 234                 buffer_get_bignum_bits(&b, key->dsa->pub_key);
 235                 buffer_get_bignum_bits(&b, key->dsa->priv_key);
 236                 break;
 237         case KEY_RSA:
 238                 if (!BN_set_word(key->rsa->e, (u_long) buffer_get_char(&b))) {
 239                         buffer_free(&b);
 240                         key_free(key);
 241                         return NULL;
 242                 }
 243                 buffer_get_bignum_bits(&b, key->rsa->d);
 244                 buffer_get_bignum_bits(&b, key->rsa->n);
 245                 buffer_get_bignum_bits(&b, key->rsa->iqmp);
 246                 buffer_get_bignum_bits(&b, key->rsa->q);
 247                 buffer_get_bignum_bits(&b, key->rsa->p);
 248                 generate_additional_parameters(key->rsa);
 249                 break;
 250         }
 251         rlen = buffer_len(&b);
 252         if(rlen != 0)
 253                 error("do_convert_private_ssh2_from_blob: "
 254                     "remaining bytes in key blob %d", rlen);
 255         buffer_free(&b);
 256 #ifdef DEBUG_PK
 257         {
 258                 u_int slen;
 259                 u_char *sig, data[10] = "abcde12345";
 260
 261                 key_sign(key, &sig, &slen, data, sizeof data);
 262                 key_verify(key, sig, slen, data, sizeof data);
 263                 xfree(sig);
 264         }
 265 #endif
 266         return key;
 267 }
 268
 269 void
 270 do_convert_from_ssh2(struct passwd *pw)
 271 {
 272         Key *k;
 273         int blen;
 274         char line[1024], *p;
 275         char blob[8096];
 276         char encoded[8096];
 277         struct stat st;
 278         int escaped = 0, private = 0, ok;
 279         FILE *fp;
 280
 281         if (!have_identity)
 282                 ask_filename(pw, "Enter file in which the key is");
 283         if (stat(identity_file, &st) < 0) {
 284                 perror(identity_file);
 285                 exit(1);
 286         }
 287         fp = fopen(identity_file, "r");
 288         if (fp == NULL) {
 289                 perror(identity_file);
 290                 exit(1);
 291         }
 292         encoded[0] = '\0';
 293         while (fgets(line, sizeof(line), fp)) {
 294                 if (!(p = strchr(line, '\n'))) {
 295                         fprintf(stderr, "input line too long.\n");
 296                         exit(1);
 297                 }
 298                 if (p > line && p[-1] == '\\')
 299                         escaped++;
 300                 if (strncmp(line, "----", 4) == 0 ||
 301                     strstr(line, ": ") != NULL) {
 302                         if (strstr(line, SSH_COM_PRIVATE_BEGIN) != NULL)
 303                                 private = 1;
 304                         /* fprintf(stderr, "ignore: %s", line); */
 305                         continue;
 306                 }
 307                 if (escaped) {
 308                         escaped--;
 309                         /* fprintf(stderr, "escaped: %s", line); */
 310                         continue;
 311                 }
 312                 *p = '\0';
 313                 strlcat(encoded, line, sizeof(encoded));
 314         }
 315         blen = uudecode(encoded, (u_char *)blob, sizeof(blob));
 316         if (blen < 0) {
 317                 fprintf(stderr, "uudecode failed.\n");
 318                 exit(1);
 319         }
 320         k = private ?
 321             do_convert_private_ssh2_from_blob(blob, blen) :
 322             key_from_blob(blob, blen);
 323         if (k == NULL) {
 324                 fprintf(stderr, "decode blob failed.\n");
 325                 exit(1);
 326         }
 327         ok = private ?
 328             (k->type == KEY_DSA ?
 329                  PEM_write_DSAPrivateKey(stdout, k->dsa, NULL, NULL, 0, NULL, NULL) :
 330                  PEM_write_RSAPrivateKey(stdout, k->rsa, NULL, NULL, 0, NULL, NULL)) :
 331             key_write(k, stdout);
 332         if (!ok) {
 333                 fprintf(stderr, "key write failed");
 334                 exit(1);
 335         }
 336         key_free(k);
 337         fprintf(stdout, "\n");
 338         fclose(fp);
 339         exit(0);
 340 }
 341
 342 void
 343 do_print_public(struct passwd *pw)
 344 {
 345         Key *prv;
 346         struct stat st;
 347
 348         if (!have_identity)
 349                 ask_filename(pw, "Enter file in which the key is");
 350         if (stat(identity_file, &st) < 0) {
 351                 perror(identity_file);
 352                 exit(1);
 353         }
 354         prv = load_identity(identity_file);
 355         if (prv == NULL) {
 356                 fprintf(stderr, "load failed\n");
 357                 exit(1);
 358         }
 359         if (!key_write(prv, stdout))
 360                 fprintf(stderr, "key_write failed");
 361         key_free(prv);
 362         fprintf(stdout, "\n");
 363         exit(0);
 364 }
 365
 366 void
 367 do_fingerprint(struct passwd *pw)
 368 {
 369         FILE *f;
 370         Key *public;
 371         char *comment = NULL, *cp, *ep, line[16*1024], *fp;
 372         int i, skip = 0, num = 1, invalid = 1, rep, fptype;
 373         struct stat st;
 374
 375         fptype = print_bubblebabble ? SSH_FP_SHA1 : SSH_FP_MD5;
 376         rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_HEX;
 377
 378         if (!have_identity)
 379                 ask_filename(pw, "Enter file in which the key is");
 380         if (stat(identity_file, &st) < 0) {
 381                 perror(identity_file);
 382                 exit(1);
 383         }
 384         public = key_load_public(identity_file, &comment);
 385         if (public != NULL) {
 386                 fp = key_fingerprint(public, fptype, rep);
 387                 printf("%d %s %s\n", key_size(public), fp, comment);
 388                 key_free(public);
 389                 xfree(comment);
 390                 xfree(fp);
 391                 exit(0);
 392         }
 393         if (comment)
 394                 xfree(comment);
 395
 396         f = fopen(identity_file, "r");
 397         if (f != NULL) {
 398                 while (fgets(line, sizeof(line), f)) {
 399                         i = strlen(line) - 1;
 400                         if (line[i] != '\n') {
 401                                 error("line %d too long: %.40s...", num, line);
 402                                 skip = 1;
 403                                 continue;
 404                         }
 405                         num++;
 406                         if (skip) {
 407                                 skip = 0;
 408                                 continue;
 409                         }
 410                         line[i] = '\0';
 411
 412                         /* Skip leading whitespace, empty and comment lines. */
 413                         for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
 414                                 ;
 415                         if (!*cp || *cp == '\n' || *cp == '#')
 416                                 continue ;
 417                         i = strtol(cp, &ep, 10);
 418                         if (i == 0 || ep == NULL || (*ep != ' ' && *ep != '\t')) {
 419                                 int quoted = 0;
 420                                 comment = cp;
 421                                 for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
 422                                         if (*cp == '\\' && cp[1] == '"')
 423                                                 cp++;   /* Skip both */
 424                                         else if (*cp == '"')
 425                                                 quoted = !quoted;
 426                                 }
 427                                 if (!*cp)
 428                                         continue;
 429                                 *cp++ = '\0';
 430                         }
 431                         ep = cp;
 432                         public = key_new(KEY_RSA1);
 433                         if (key_read(public, &cp) != 1) {
 434                                 cp = ep;
 435                                 key_free(public);
 436                                 public = key_new(KEY_UNSPEC);
 437                                 if (key_read(public, &cp) != 1) {
 438                                         key_free(public);
 439                                         continue;
 440                                 }
 441                         }
 442                         comment = *cp ? cp : comment;
 443                         fp = key_fingerprint(public, fptype, rep);
 444                         printf("%d %s %s\n", key_size(public), fp,
 445                             comment ? comment : "no comment");
 446                         xfree(fp);
 447                         key_free(public);
 448                         invalid = 0;
 449                 }
 450                 fclose(f);
 451         }
 452         if (invalid) {
 453                 printf("%s is not a valid key file.\n", identity_file);
 454                 exit(1);
 455         }
 456         exit(0);
 457 }
 458
 459 /*
 460  * Perform changing a passphrase.  The argument is the passwd structure
 461  * for the current user.
 462  */
 463 void
 464 do_change_passphrase(struct passwd *pw)
 465 {
 466         char *comment;
 467         char *old_passphrase, *passphrase1, *passphrase2;
 468         struct stat st;
 469         Key *private;
 470
 471         if (!have_identity)
 472                 ask_filename(pw, "Enter file in which the key is");
 473         if (stat(identity_file, &st) < 0) {
 474                 perror(identity_file);
 475                 exit(1);
 476         }
 477         /* Try to load the file with empty passphrase. */
 478         private = key_load_private(identity_file, "", &comment);
 479         if (private == NULL) {
 480                 if (identity_passphrase)
 481                         old_passphrase = xstrdup(identity_passphrase);
 482                 else
 483                         old_passphrase = read_passphrase("Enter old passphrase: ", 1);
 484                 private = key_load_private(identity_file, old_passphrase , &comment);
 485                 memset(old_passphrase, 0, strlen(old_passphrase));
 486                 xfree(old_passphrase);
 487                 if (private == NULL) {
 488                         printf("Bad passphrase.\n");
 489                         exit(1);
 490                 }
 491         }
 492         printf("Key has comment '%s'\n", comment);
 493
 494         /* Ask the new passphrase (twice). */
 495         if (identity_new_passphrase) {
 496                 passphrase1 = xstrdup(identity_new_passphrase);
 497                 passphrase2 = NULL;
 498         } else {
 499                 passphrase1 =
 500                         read_passphrase("Enter new passphrase (empty for no passphrase): ", 1);
 501                 passphrase2 = read_passphrase("Enter same passphrase again: ", 1);
 502
 503                 /* Verify that they are the same. */
 504                 if (strcmp(passphrase1, passphrase2) != 0) {
 505                         memset(passphrase1, 0, strlen(passphrase1));
 506                         memset(passphrase2, 0, strlen(passphrase2));
 507                         xfree(passphrase1);
 508                         xfree(passphrase2);
 509                         printf("Pass phrases do not match.  Try again.\n");
 510                         exit(1);
 511                 }
 512                 /* Destroy the other copy. */
 513                 memset(passphrase2, 0, strlen(passphrase2));
 514                 xfree(passphrase2);
 515         }
 516
 517         /* Save the file using the new passphrase. */
 518         if (!key_save_private(private, identity_file, passphrase1, comment)) {
 519                 printf("Saving the key failed: %s.\n", identity_file);
 520                 memset(passphrase1, 0, strlen(passphrase1));
 521                 xfree(passphrase1);
 522                 key_free(private);
 523                 xfree(comment);
 524                 exit(1);
 525         }
 526         /* Destroy the passphrase and the copy of the key in memory. */
 527         memset(passphrase1, 0, strlen(passphrase1));
 528         xfree(passphrase1);
 529         key_free(private);               /* Destroys contents */
 530         xfree(comment);
 531
 532         printf("Your identification has been saved with the new passphrase.\n");
 533         exit(0);
 534 }
 535
 536 /*
 537  * Change the comment of a private key file.
 538  */
 539 void
 540 do_change_comment(struct passwd *pw)
 541 {
 542         char new_comment[1024], *comment, *passphrase;
 543         Key *private;
 544         Key *public;
 545         struct stat st;
 546         FILE *f;
 547         int fd;
 548
 549         if (!have_identity)
 550                 ask_filename(pw, "Enter file in which the key is");
 551         if (stat(identity_file, &st) < 0) {
 552                 perror(identity_file);
 553                 exit(1);
 554         }
 555         private = key_load_private(identity_file, "", &comment);
 556         if (private == NULL) {
 557                 if (identity_passphrase)
 558                         passphrase = xstrdup(identity_passphrase);
 559                 else if (identity_new_passphrase)
 560                         passphrase = xstrdup(identity_new_passphrase);
 561                 else
 562                         passphrase = read_passphrase("Enter passphrase: ", 1);
 563                 /* Try to load using the passphrase. */
 564                 private = key_load_private(identity_file, passphrase, &comment);
 565                 if (private == NULL) {
 566                         memset(passphrase, 0, strlen(passphrase));
 567                         xfree(passphrase);
 568                         printf("Bad passphrase.\n");
 569                         exit(1);
 570                 }
 571         } else {
 572                 passphrase = xstrdup("");
 573         }
 574         if (private->type != KEY_RSA1) {
 575                 fprintf(stderr, "Comments are only supported for RSA1 keys.\n");
 576                 key_free(private);
 577                 exit(1);
 578         }
 579         printf("Key now has comment '%s'\n", comment);
 580
 581         if (identity_comment) {
 582                 strlcpy(new_comment, identity_comment, sizeof(new_comment));
 583         } else {
 584                 printf("Enter new comment: ");
 585                 fflush(stdout);
 586                 if (!fgets(new_comment, sizeof(new_comment), stdin)) {
 587                         memset(passphrase, 0, strlen(passphrase));
 588                         key_free(private);
 589                         exit(1);
 590                 }
 591                 if (strchr(new_comment, '\n'))
 592                         *strchr(new_comment, '\n') = 0;
 593         }
 594
 595         /* Save the file using the new passphrase. */
 596         if (!key_save_private(private, identity_file, passphrase, new_comment)) {
 597                 printf("Saving the key failed: %s.\n", identity_file);
 598                 memset(passphrase, 0, strlen(passphrase));
 599                 xfree(passphrase);
 600                 key_free(private);
 601                 xfree(comment);
 602                 exit(1);
 603         }
 604         memset(passphrase, 0, strlen(passphrase));
 605         xfree(passphrase);
 606         public = key_from_private(private);
 607         key_free(private);
 608
 609         strlcat(identity_file, ".pub", sizeof(identity_file));
 610         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 611         if (fd == -1) {
 612                 printf("Could not save your public key in %s\n", identity_file);
 613                 exit(1);
 614         }
 615         f = fdopen(fd, "w");
 616         if (f == NULL) {
 617                 printf("fdopen %s failed", identity_file);
 618                 exit(1);
 619         }
 620         if (!key_write(public, f))
 621                 fprintf(stderr, "write key failed");
 622         key_free(public);
 623         fprintf(f, " %s\n", new_comment);
 624         fclose(f);
 625
 626         xfree(comment);
 627
 628         printf("The comment in your key file has been changed.\n");
 629         exit(0);
 630 }
 631
 632 void
 633 usage(void)
 634 {
 635         printf("Usage: %s [-ceilpqyB] [-t type] [-b bits] [-f file] [-C comment] "
 636             "[-N new-pass] [-P pass]\n", __progname);
 637         exit(1);
 638 }
 639
 640 /*
 641  * Main program for key management.
 642  */
 643 int
 644 main(int ac, char **av)
 645 {
 646         char dotsshdir[16 * 1024], comment[1024], *passphrase1, *passphrase2;
 647         Key *private, *public;
 648         struct passwd *pw;
 649         int opt, type, fd;
 650         struct stat st;
 651         FILE *f;
 652
 653         extern int optind;
 654         extern char *optarg;
 655
 656         __progname = get_progname(av[0]);
 657         init_rng();
 658         seed_rng();
 659
 660         SSLeay_add_all_algorithms();
 661
 662         /* we need this for the home * directory.  */
 663         pw = getpwuid(getuid());
 664         if (!pw) {
 665                 printf("You don't exist, go away!\n");
 666                 exit(1);
 667         }
 668         if (gethostname(hostname, sizeof(hostname)) < 0) {
 669                 perror("gethostname");
 670                 exit(1);
 671         }
 672
 673         while ((opt = getopt(ac, av, "deiqpclBRxXyb:f:t:P:N:C:")) != -1) {
 674                 switch (opt) {
 675                 case 'b':
 676                         bits = atoi(optarg);
 677                         if (bits < 512 || bits > 32768) {
 678                                 printf("Bits has bad value.\n");
 679                                 exit(1);
 680                         }
 681                         break;
 682
 683                 case 'l':
 684                         print_fingerprint = 1;
 685                         break;
 686
 687                 case 'B':
 688                         print_bubblebabble = 1;
 689                         break;
 690
 691                 case 'p':
 692                         change_passphrase = 1;
 693                         break;
 694
 695                 case 'c':
 696                         change_comment = 1;
 697                         break;
 698
 699                 case 'f':
 700                         strlcpy(identity_file, optarg, sizeof(identity_file));
 701                         have_identity = 1;
 702                         break;
 703
 704                 case 'P':
 705                         identity_passphrase = optarg;
 706                         break;
 707
 708                 case 'N':
 709                         identity_new_passphrase = optarg;
 710                         break;
 711
 712                 case 'C':
 713                         identity_comment = optarg;
 714                         break;
 715
 716                 case 'q':
 717                         quiet = 1;
 718                         break;
 719
 720                 case 'R':
 721                         /* unused */
 722                         exit(0);
 723                         break;
 724
 725                 case 'e':
 726                 case 'x':
 727                         /* export key */
 728                         convert_to_ssh2 = 1;
 729                         break;
 730
 731                 case 'i':
 732                 case 'X':
 733                         /* import key */
 734                         convert_from_ssh2 = 1;
 735                         break;
 736
 737                 case 'y':
 738                         print_public = 1;
 739                         break;
 740
 741                 case 'd':
 742                         key_type_name = "dsa";
 743                         break;
 744
 745                 case 't':
 746                         key_type_name = optarg;
 747                         break;
 748
 749                 case '?':
 750                 default:
 751                         usage();
 752                 }
 753         }
 754         if (optind < ac) {
 755                 printf("Too many arguments.\n");
 756                 usage();
 757         }
 758         if (change_passphrase && change_comment) {
 759                 printf("Can only have one of -p and -c.\n");
 760                 usage();
 761         }
 762         if (print_fingerprint || print_bubblebabble)
 763                 do_fingerprint(pw);
 764         if (change_passphrase)
 765                 do_change_passphrase(pw);
 766         if (change_comment)
 767                 do_change_comment(pw);
 768         if (convert_to_ssh2)
 769                 do_convert_to_ssh2(pw);
 770         if (convert_from_ssh2)
 771                 do_convert_from_ssh2(pw);
 772         if (print_public)
 773                 do_print_public(pw);
 774
 775         arc4random_stir();
 776
 777         type = key_type_from_name(key_type_name);
 778         if (type == KEY_UNSPEC) {
 779                 fprintf(stderr, "unknown key type %s\n", key_type_name);
 780                 exit(1);
 781         }
 782         if (!quiet)
 783                 printf("Generating public/private %s key pair.\n", key_type_name);
 784         private = key_generate(type, bits);
 785         if (private == NULL) {
 786                 fprintf(stderr, "key_generate failed");
 787                 exit(1);
 788         }
 789         public  = key_from_private(private);
 790
 791         if (!have_identity)
 792                 ask_filename(pw, "Enter file in which to save the key");
 793
 794         /* Create ~/.ssh directory if it doesn\'t already exist. */
 795         snprintf(dotsshdir, sizeof dotsshdir, "%s/%s", pw->pw_dir, _PATH_SSH_USER_DIR);
 796         if (strstr(identity_file, dotsshdir) != NULL &&
 797             stat(dotsshdir, &st) < 0) {
 798                 if (mkdir(dotsshdir, 0700) < 0)
 799                         error("Could not create directory '%s'.", dotsshdir);
 800                 else if (!quiet)
 801                         printf("Created directory '%s'.\n", dotsshdir);
 802         }
 803         /* If the file already exists, ask the user to confirm. */
 804         if (stat(identity_file, &st) >= 0) {
 805                 char yesno[3];
 806                 printf("%s already exists.\n", identity_file);
 807                 printf("Overwrite (y/n)? ");
 808                 fflush(stdout);
 809                 if (fgets(yesno, sizeof(yesno), stdin) == NULL)
 810                         exit(1);
 811                 if (yesno[0] != 'y' && yesno[0] != 'Y')
 812                         exit(1);
 813         }
 814         /* Ask for a passphrase (twice). */
 815         if (identity_passphrase)
 816                 passphrase1 = xstrdup(identity_passphrase);
 817         else if (identity_new_passphrase)
 818                 passphrase1 = xstrdup(identity_new_passphrase);
 819         else {
 820 passphrase_again:
 821                 passphrase1 =
 822                         read_passphrase("Enter passphrase (empty for no passphrase): ", 1);
 823                 passphrase2 = read_passphrase("Enter same passphrase again: ", 1);
 824                 if (strcmp(passphrase1, passphrase2) != 0) {
 825                         /* The passphrases do not match.  Clear them and retry. */
 826                         memset(passphrase1, 0, strlen(passphrase1));
 827                         memset(passphrase2, 0, strlen(passphrase2));
 828                         xfree(passphrase1);
 829                         xfree(passphrase2);
 830                         printf("Passphrases do not match.  Try again.\n");
 831                         goto passphrase_again;
 832                 }
 833                 /* Clear the other copy of the passphrase. */
 834                 memset(passphrase2, 0, strlen(passphrase2));
 835                 xfree(passphrase2);
 836         }
 837
 838         if (identity_comment) {
 839                 strlcpy(comment, identity_comment, sizeof(comment));
 840         } else {
 841                 /* Create default commend field for the passphrase. */
 842                 snprintf(comment, sizeof comment, "%s@%s", pw->pw_name, hostname);
 843         }
 844
 845         /* Save the key with the given passphrase and comment. */
 846         if (!key_save_private(private, identity_file, passphrase1, comment)) {
 847                 printf("Saving the key failed: %s.\n", identity_file);
 848                 memset(passphrase1, 0, strlen(passphrase1));
 849                 xfree(passphrase1);
 850                 exit(1);
 851         }
 852         /* Clear the passphrase. */
 853         memset(passphrase1, 0, strlen(passphrase1));
 854         xfree(passphrase1);
 855
 856         /* Clear the private key and the random number generator. */
 857         key_free(private);
 858         arc4random_stir();
 859
 860         if (!quiet)
 861                 printf("Your identification has been saved in %s.\n", identity_file);
 862
 863         strlcat(identity_file, ".pub", sizeof(identity_file));
 864         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 865         if (fd == -1) {
 866                 printf("Could not save your public key in %s\n", identity_file);
 867                 exit(1);
 868         }
 869         f = fdopen(fd, "w");
 870         if (f == NULL) {
 871                 printf("fdopen %s failed", identity_file);
 872                 exit(1);
 873         }
 874         if (!key_write(public, f))
 875                 fprintf(stderr, "write key failed");
 876         fprintf(f, " %s\n", comment);
 877         fclose(f);
 878
 879         if (!quiet) {
 880                 char *fp = key_fingerprint(public, SSH_FP_MD5, SSH_FP_HEX);
 881                 printf("Your public key has been saved in %s.\n",
 882                     identity_file);
 883                 printf("The key fingerprint is:\n");
 884                 printf("%s %s\n", fp, comment);
 885                 xfree(fp);
 886         }
 887
 888         key_free(public);
 889         exit(0);
 890 }