crypto/openssh/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 1.60 2001/04/23 22:14:13 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 extern char *__progname;
  75
  76 char hostname[MAXHOSTNAMELEN];
  77
  78 void
  79 ask_filename(struct passwd *pw, const char *prompt)
  80 {
  81         char buf[1024];
  82         char *name = NULL;
  83
  84         switch (key_type_from_name(key_type_name)) {
  85         case KEY_RSA1:
  86                 name = _PATH_SSH_CLIENT_IDENTITY;
  87                 break;
  88         case KEY_DSA:
  89                 name = _PATH_SSH_CLIENT_ID_DSA;
  90                 break;
  91         case KEY_RSA:
  92                 name = _PATH_SSH_CLIENT_ID_RSA;
  93                 break;
  94         default:
  95                 fprintf(stderr, "bad key type");
  96                 exit(1);
  97                 break;
  98         }
  99         snprintf(identity_file, sizeof(identity_file), "%s/%s", pw->pw_dir, name);
 100         fprintf(stderr, "%s (%s): ", prompt, identity_file);
 101         fflush(stderr);
 102         if (fgets(buf, sizeof(buf), stdin) == NULL)
 103                 exit(1);
 104         if (strchr(buf, '\n'))
 105                 *strchr(buf, '\n') = 0;
 106         if (strcmp(buf, "") != 0)
 107                 strlcpy(identity_file, buf, sizeof(identity_file));
 108         have_identity = 1;
 109 }
 110
 111 Key *
 112 try_load_pem_key(char *filename)
 113 {
 114         char *pass;
 115         Key *prv;
 116
 117         prv = key_load_private(filename, "", NULL);
 118         if (prv == NULL) {
 119                 pass = read_passphrase("Enter passphrase: ", 1);
 120                 prv = key_load_private(filename, pass, NULL);
 121                 memset(pass, 0, strlen(pass));
 122                 xfree(pass);
 123         }
 124         return prv;
 125 }
 126
 127 #define SSH_COM_PUBLIC_BEGIN            "---- BEGIN SSH2 PUBLIC KEY ----"
 128 #define SSH_COM_PUBLIC_END              "---- END SSH2 PUBLIC KEY ----"
 129 #define SSH_COM_PRIVATE_BEGIN           "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----"
 130 #define SSH_COM_PRIVATE_KEY_MAGIC       0x3f6ff9eb
 131
 132 void
 133 do_convert_to_ssh2(struct passwd *pw)
 134 {
 135         Key *k;
 136         int len;
 137         u_char *blob;
 138         struct stat st;
 139
 140         if (!have_identity)
 141                 ask_filename(pw, "Enter file in which the key is");
 142         if (stat(identity_file, &st) < 0) {
 143                 perror(identity_file);
 144                 exit(1);
 145         }
 146         if ((k = key_load_public(identity_file, NULL)) == NULL) {
 147                 if ((k = try_load_pem_key(identity_file)) == NULL) {
 148                         fprintf(stderr, "load failed\n");
 149                         exit(1);
 150                 }
 151         }
 152         key_to_blob(k, &blob, &len);
 153         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_BEGIN);
 154         fprintf(stdout,
 155             "Comment: \"%d-bit %s, converted from OpenSSH by %s@%s\"\n",
 156             key_size(k), key_type(k),
 157             pw->pw_name, hostname);
 158         dump_base64(stdout, blob, len);
 159         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_END);
 160         key_free(k);
 161         xfree(blob);
 162         exit(0);
 163 }
 164
 165 void
 166 buffer_get_bignum_bits(Buffer *b, BIGNUM *value)
 167 {
 168         int bits = buffer_get_int(b);
 169         int bytes = (bits + 7) / 8;
 170
 171         if (buffer_len(b) < bytes)
 172                 fatal("buffer_get_bignum_bits: input buffer too small: "
 173                     "need %d have %d", bytes, buffer_len(b));
 174         BN_bin2bn((u_char *)buffer_ptr(b), bytes, value);
 175         buffer_consume(b, bytes);
 176 }
 177
 178 Key *
 179 do_convert_private_ssh2_from_blob(char *blob, int blen)
 180 {
 181         Buffer b;
 182         Key *key = NULL;
 183         int ignore, magic, rlen, ktype;
 184         char *type, *cipher;
 185
 186         buffer_init(&b);
 187         buffer_append(&b, blob, blen);
 188
 189         magic  = buffer_get_int(&b);
 190         if (magic != SSH_COM_PRIVATE_KEY_MAGIC) {
 191                 error("bad magic 0x%x != 0x%x", magic, SSH_COM_PRIVATE_KEY_MAGIC);
 192                 buffer_free(&b);
 193                 return NULL;
 194         }
 195         ignore = buffer_get_int(&b);
 196         type   = buffer_get_string(&b, NULL);
 197         cipher = buffer_get_string(&b, NULL);
 198         ignore = buffer_get_int(&b);
 199         ignore = buffer_get_int(&b);
 200         ignore = buffer_get_int(&b);
 201
 202         if (strcmp(cipher, "none") != 0) {
 203                 error("unsupported cipher %s", cipher);
 204                 xfree(cipher);
 205                 buffer_free(&b);
 206                 xfree(type);
 207                 return NULL;
 208         }
 209         xfree(cipher);
 210
 211         if (strstr(type, "dsa")) {
 212                 ktype = KEY_DSA;
 213         } else if (strstr(type, "rsa")) {
 214                 ktype = KEY_RSA;
 215         } else {
 216                 xfree(type);
 217                 return NULL;
 218         }
 219         key = key_new_private(ktype);
 220         xfree(type);
 221
 222         switch (key->type) {
 223         case KEY_DSA:
 224                 buffer_get_bignum_bits(&b, key->dsa->p);
 225                 buffer_get_bignum_bits(&b, key->dsa->g);
 226                 buffer_get_bignum_bits(&b, key->dsa->q);
 227                 buffer_get_bignum_bits(&b, key->dsa->pub_key);
 228                 buffer_get_bignum_bits(&b, key->dsa->priv_key);
 229                 break;
 230         case KEY_RSA:
 231                 if (!BN_set_word(key->rsa->e, (u_long) buffer_get_char(&b))) {
 232                         buffer_free(&b);
 233                         key_free(key);
 234                         return NULL;
 235                 }
 236                 buffer_get_bignum_bits(&b, key->rsa->d);
 237                 buffer_get_bignum_bits(&b, key->rsa->n);
 238                 buffer_get_bignum_bits(&b, key->rsa->iqmp);
 239                 buffer_get_bignum_bits(&b, key->rsa->q);
 240                 buffer_get_bignum_bits(&b, key->rsa->p);
 241                 generate_additional_parameters(key->rsa);
 242                 break;
 243         }
 244         rlen = buffer_len(&b);
 245         if(rlen != 0)
 246                 error("do_convert_private_ssh2_from_blob: "
 247                     "remaining bytes in key blob %d", rlen);
 248         buffer_free(&b);
 249 #ifdef DEBUG_PK
 250         {
 251                 u_int slen;
 252                 u_char *sig, data[10] = "abcde12345";
 253
 254                 key_sign(key, &sig, &slen, data, sizeof data);
 255                 key_verify(key, sig, slen, data, sizeof data);
 256                 xfree(sig);
 257         }
 258 #endif
 259         return key;
 260 }
 261
 262 void
 263 do_convert_from_ssh2(struct passwd *pw)
 264 {
 265         Key *k;
 266         int blen;
 267         char line[1024], *p;
 268         char blob[8096];
 269         char encoded[8096];
 270         struct stat st;
 271         int escaped = 0, private = 0, ok;
 272         FILE *fp;
 273
 274         if (!have_identity)
 275                 ask_filename(pw, "Enter file in which the key is");
 276         if (stat(identity_file, &st) < 0) {
 277                 perror(identity_file);
 278                 exit(1);
 279         }
 280         fp = fopen(identity_file, "r");
 281         if (fp == NULL) {
 282                 perror(identity_file);
 283                 exit(1);
 284         }
 285         encoded[0] = '\0';
 286         while (fgets(line, sizeof(line), fp)) {
 287                 if (!(p = strchr(line, '\n'))) {
 288                         fprintf(stderr, "input line too long.\n");
 289                         exit(1);
 290                 }
 291                 if (p > line && p[-1] == '\\')
 292                         escaped++;
 293                 if (strncmp(line, "----", 4) == 0 ||
 294                     strstr(line, ": ") != NULL) {
 295                         if (strstr(line, SSH_COM_PRIVATE_BEGIN) != NULL)
 296                                 private = 1;
 297                         /* fprintf(stderr, "ignore: %s", line); */
 298                         continue;
 299                 }
 300                 if (escaped) {
 301                         escaped--;
 302                         /* fprintf(stderr, "escaped: %s", line); */
 303                         continue;
 304                 }
 305                 *p = '\0';
 306                 strlcat(encoded, line, sizeof(encoded));
 307         }
 308         blen = uudecode(encoded, (u_char *)blob, sizeof(blob));
 309         if (blen < 0) {
 310                 fprintf(stderr, "uudecode failed.\n");
 311                 exit(1);
 312         }
 313         k = private ?
 314             do_convert_private_ssh2_from_blob(blob, blen) :
 315             key_from_blob(blob, blen);
 316         if (k == NULL) {
 317                 fprintf(stderr, "decode blob failed.\n");
 318                 exit(1);
 319         }
 320         ok = private ?
 321             (k->type == KEY_DSA ?
 322                  PEM_write_DSAPrivateKey(stdout, k->dsa, NULL, NULL, 0, NULL, NULL) :
 323                  PEM_write_RSAPrivateKey(stdout, k->rsa, NULL, NULL, 0, NULL, NULL)) :
 324             key_write(k, stdout);
 325         if (!ok) {
 326                 fprintf(stderr, "key write failed");
 327                 exit(1);
 328         }
 329         key_free(k);
 330         fprintf(stdout, "\n");
 331         fclose(fp);
 332         exit(0);
 333 }
 334
 335 void
 336 do_print_public(struct passwd *pw)
 337 {
 338         Key *prv;
 339         struct stat st;
 340
 341         if (!have_identity)
 342                 ask_filename(pw, "Enter file in which the key is");
 343         if (stat(identity_file, &st) < 0) {
 344                 perror(identity_file);
 345                 exit(1);
 346         }
 347         prv = try_load_pem_key(identity_file);
 348         if (prv == NULL) {
 349                 fprintf(stderr, "load failed\n");
 350                 exit(1);
 351         }
 352         if (!key_write(prv, stdout))
 353                 fprintf(stderr, "key_write failed");
 354         key_free(prv);
 355         fprintf(stdout, "\n");
 356         exit(0);
 357 }
 358
 359 void
 360 do_fingerprint(struct passwd *pw)
 361 {
 362         FILE *f;
 363         Key *public;
 364         char *comment = NULL, *cp, *ep, line[16*1024], *fp;
 365         int i, skip = 0, num = 1, invalid = 1, rep, fptype;
 366         struct stat st;
 367
 368         fptype = print_bubblebabble ? SSH_FP_SHA1 : SSH_FP_MD5;
 369         rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_HEX;
 370
 371         if (!have_identity)
 372                 ask_filename(pw, "Enter file in which the key is");
 373         if (stat(identity_file, &st) < 0) {
 374                 perror(identity_file);
 375                 exit(1);
 376         }
 377         public = key_load_public(identity_file, &comment);
 378         if (public != NULL) {
 379                 fp = key_fingerprint(public, fptype, rep);
 380                 printf("%d %s %s\n", key_size(public), fp, comment);
 381                 key_free(public);
 382                 xfree(comment);
 383                 xfree(fp);
 384                 exit(0);
 385         }
 386         if (comment)
 387                 xfree(comment);
 388
 389         f = fopen(identity_file, "r");
 390         if (f != NULL) {
 391                 while (fgets(line, sizeof(line), f)) {
 392                         i = strlen(line) - 1;
 393                         if (line[i] != '\n') {
 394                                 error("line %d too long: %.40s...", num, line);
 395                                 skip = 1;
 396                                 continue;
 397                         }
 398                         num++;
 399                         if (skip) {
 400                                 skip = 0;
 401                                 continue;
 402                         }
 403                         line[i] = '\0';
 404
 405                         /* Skip leading whitespace, empty and comment lines. */
 406                         for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
 407                                 ;
 408                         if (!*cp || *cp == '\n' || *cp == '#')
 409                                 continue ;
 410                         i = strtol(cp, &ep, 10);
 411                         if (i == 0 || ep == NULL || (*ep != ' ' && *ep != '\t')) {
 412                                 int quoted = 0;
 413                                 comment = cp;
 414                                 for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
 415                                         if (*cp == '\\' && cp[1] == '"')
 416                                                 cp++;   /* Skip both */
 417                                         else if (*cp == '"')
 418                                                 quoted = !quoted;
 419                                 }
 420                                 if (!*cp)
 421                                         continue;
 422                                 *cp++ = '\0';
 423                         }
 424                         ep = cp;
 425                         public = key_new(KEY_RSA1);
 426                         if (key_read(public, &cp) != 1) {
 427                                 cp = ep;
 428                                 key_free(public);
 429                                 public = key_new(KEY_UNSPEC);
 430                                 if (key_read(public, &cp) != 1) {
 431                                         key_free(public);
 432                                         continue;
 433                                 }
 434                         }
 435                         comment = *cp ? cp : comment;
 436                         fp = key_fingerprint(public, fptype, rep);
 437                         printf("%d %s %s\n", key_size(public), fp,
 438                             comment ? comment : "no comment");
 439                         xfree(fp);
 440                         key_free(public);
 441                         invalid = 0;
 442                 }
 443                 fclose(f);
 444         }
 445         if (invalid) {
 446                 printf("%s is not a valid key file.\n", identity_file);
 447                 exit(1);
 448         }
 449         exit(0);
 450 }
 451
 452 /*
 453  * Perform changing a passphrase.  The argument is the passwd structure
 454  * for the current user.
 455  */
 456 void
 457 do_change_passphrase(struct passwd *pw)
 458 {
 459         char *comment;
 460         char *old_passphrase, *passphrase1, *passphrase2;
 461         struct stat st;
 462         Key *private;
 463
 464         if (!have_identity)
 465                 ask_filename(pw, "Enter file in which the key is");
 466         if (stat(identity_file, &st) < 0) {
 467                 perror(identity_file);
 468                 exit(1);
 469         }
 470         /* Try to load the file with empty passphrase. */
 471         private = key_load_private(identity_file, "", &comment);
 472         if (private == NULL) {
 473                 if (identity_passphrase)
 474                         old_passphrase = xstrdup(identity_passphrase);
 475                 else
 476                         old_passphrase = read_passphrase("Enter old passphrase: ", 1);
 477                 private = key_load_private(identity_file, old_passphrase , &comment);
 478                 memset(old_passphrase, 0, strlen(old_passphrase));
 479                 xfree(old_passphrase);
 480                 if (private == NULL) {
 481                         printf("Bad passphrase.\n");
 482                         exit(1);
 483                 }
 484         }
 485         printf("Key has comment '%s'\n", comment);
 486
 487         /* Ask the new passphrase (twice). */
 488         if (identity_new_passphrase) {
 489                 passphrase1 = xstrdup(identity_new_passphrase);
 490                 passphrase2 = NULL;
 491         } else {
 492                 passphrase1 =
 493                         read_passphrase("Enter new passphrase (empty for no passphrase): ", 1);
 494                 passphrase2 = read_passphrase("Enter same passphrase again: ", 1);
 495
 496                 /* Verify that they are the same. */
 497                 if (strcmp(passphrase1, passphrase2) != 0) {
 498                         memset(passphrase1, 0, strlen(passphrase1));
 499                         memset(passphrase2, 0, strlen(passphrase2));
 500                         xfree(passphrase1);
 501                         xfree(passphrase2);
 502                         printf("Pass phrases do not match.  Try again.\n");
 503                         exit(1);
 504                 }
 505                 /* Destroy the other copy. */
 506                 memset(passphrase2, 0, strlen(passphrase2));
 507                 xfree(passphrase2);
 508         }
 509
 510         /* Save the file using the new passphrase. */
 511         if (!key_save_private(private, identity_file, passphrase1, comment)) {
 512                 printf("Saving the key failed: %s.\n", identity_file);
 513                 memset(passphrase1, 0, strlen(passphrase1));
 514                 xfree(passphrase1);
 515                 key_free(private);
 516                 xfree(comment);
 517                 exit(1);
 518         }
 519         /* Destroy the passphrase and the copy of the key in memory. */
 520         memset(passphrase1, 0, strlen(passphrase1));
 521         xfree(passphrase1);
 522         key_free(private);               /* Destroys contents */
 523         xfree(comment);
 524
 525         printf("Your identification has been saved with the new passphrase.\n");
 526         exit(0);
 527 }
 528
 529 /*
 530  * Change the comment of a private key file.
 531  */
 532 void
 533 do_change_comment(struct passwd *pw)
 534 {
 535         char new_comment[1024], *comment, *passphrase;
 536         Key *private;
 537         Key *public;
 538         struct stat st;
 539         FILE *f;
 540         int fd;
 541
 542         if (!have_identity)
 543                 ask_filename(pw, "Enter file in which the key is");
 544         if (stat(identity_file, &st) < 0) {
 545                 perror(identity_file);
 546                 exit(1);
 547         }
 548         private = key_load_private(identity_file, "", &comment);
 549         if (private == NULL) {
 550                 if (identity_passphrase)
 551                         passphrase = xstrdup(identity_passphrase);
 552                 else if (identity_new_passphrase)
 553                         passphrase = xstrdup(identity_new_passphrase);
 554                 else
 555                         passphrase = read_passphrase("Enter passphrase: ", 1);
 556                 /* Try to load using the passphrase. */
 557                 private = key_load_private(identity_file, passphrase, &comment);
 558                 if (private == NULL) {
 559                         memset(passphrase, 0, strlen(passphrase));
 560                         xfree(passphrase);
 561                         printf("Bad passphrase.\n");
 562                         exit(1);
 563                 }
 564         } else {
 565                 passphrase = xstrdup("");
 566         }
 567         if (private->type != KEY_RSA1) {
 568                 fprintf(stderr, "Comments are only supported for RSA1 keys.\n");
 569                 key_free(private);
 570                 exit(1);
 571         }
 572         printf("Key now has comment '%s'\n", comment);
 573
 574         if (identity_comment) {
 575                 strlcpy(new_comment, identity_comment, sizeof(new_comment));
 576         } else {
 577                 printf("Enter new comment: ");
 578                 fflush(stdout);
 579                 if (!fgets(new_comment, sizeof(new_comment), stdin)) {
 580                         memset(passphrase, 0, strlen(passphrase));
 581                         key_free(private);
 582                         exit(1);
 583                 }
 584                 if (strchr(new_comment, '\n'))
 585                         *strchr(new_comment, '\n') = 0;
 586         }
 587
 588         /* Save the file using the new passphrase. */
 589         if (!key_save_private(private, identity_file, passphrase, new_comment)) {
 590                 printf("Saving the key failed: %s.\n", identity_file);
 591                 memset(passphrase, 0, strlen(passphrase));
 592                 xfree(passphrase);
 593                 key_free(private);
 594                 xfree(comment);
 595                 exit(1);
 596         }
 597         memset(passphrase, 0, strlen(passphrase));
 598         xfree(passphrase);
 599         public = key_from_private(private);
 600         key_free(private);
 601
 602         strlcat(identity_file, ".pub", sizeof(identity_file));
 603         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 604         if (fd == -1) {
 605                 printf("Could not save your public key in %s\n", identity_file);
 606                 exit(1);
 607         }
 608         f = fdopen(fd, "w");
 609         if (f == NULL) {
 610                 printf("fdopen %s failed", identity_file);
 611                 exit(1);
 612         }
 613         if (!key_write(public, f))
 614                 fprintf(stderr, "write key failed");
 615         key_free(public);
 616         fprintf(f, " %s\n", new_comment);
 617         fclose(f);
 618
 619         xfree(comment);
 620
 621         printf("The comment in your key file has been changed.\n");
 622         exit(0);
 623 }
 624
 625 void
 626 usage(void)
 627 {
 628         printf("Usage: %s [-ceilpqyB] [-t type] [-b bits] [-f file] [-C comment] "
 629             "[-N new-pass] [-P pass]\n", __progname);
 630         exit(1);
 631 }
 632
 633 /*
 634  * Main program for key management.
 635  */
 636 int
 637 main(int ac, char **av)
 638 {
 639         char dotsshdir[16 * 1024], comment[1024], *passphrase1, *passphrase2;
 640         Key *private, *public;
 641         struct passwd *pw;
 642         int opt, type, fd;
 643         struct stat st;
 644         FILE *f;
 645
 646         extern int optind;
 647         extern char *optarg;
 648
 649         SSLeay_add_all_algorithms();
 650
 651         /* we need this for the home * directory.  */
 652         pw = getpwuid(getuid());
 653         if (!pw) {
 654                 printf("You don't exist, go away!\n");
 655                 exit(1);
 656         }
 657         if (gethostname(hostname, sizeof(hostname)) < 0) {
 658                 perror("gethostname");
 659                 exit(1);
 660         }
 661
 662         while ((opt = getopt(ac, av, "deiqpclBRxXyb:f:t:P:N:C:")) != -1) {
 663                 switch (opt) {
 664                 case 'b':
 665                         bits = atoi(optarg);
 666                         if (bits < 512 || bits > 32768) {
 667                                 printf("Bits has bad value.\n");
 668                                 exit(1);
 669                         }
 670                         break;
 671
 672                 case 'l':
 673                         print_fingerprint = 1;
 674                         break;
 675
 676                 case 'B':
 677                         print_bubblebabble = 1;
 678                         break;
 679
 680                 case 'p':
 681                         change_passphrase = 1;
 682                         break;
 683
 684                 case 'c':
 685                         change_comment = 1;
 686                         break;
 687
 688                 case 'f':
 689                         strlcpy(identity_file, optarg, sizeof(identity_file));
 690                         have_identity = 1;
 691                         break;
 692
 693                 case 'P':
 694                         identity_passphrase = optarg;
 695                         break;
 696
 697                 case 'N':
 698                         identity_new_passphrase = optarg;
 699                         break;
 700
 701                 case 'C':
 702                         identity_comment = optarg;
 703                         break;
 704
 705                 case 'q':
 706                         quiet = 1;
 707                         break;
 708
 709                 case 'R':
 710                         /* unused */
 711                         exit(0);
 712                         break;
 713
 714                 case 'e':
 715                 case 'x':
 716                         /* export key */
 717                         convert_to_ssh2 = 1;
 718                         break;
 719
 720                 case 'i':
 721                 case 'X':
 722                         /* import key */
 723                         convert_from_ssh2 = 1;
 724                         break;
 725
 726                 case 'y':
 727                         print_public = 1;
 728                         break;
 729
 730                 case 'd':
 731                         key_type_name = "dsa";
 732                         break;
 733
 734                 case 't':
 735                         key_type_name = optarg;
 736                         break;
 737
 738                 case '?':
 739                 default:
 740                         usage();
 741                 }
 742         }
 743         if (optind < ac) {
 744                 printf("Too many arguments.\n");
 745                 usage();
 746         }
 747         if (change_passphrase && change_comment) {
 748                 printf("Can only have one of -p and -c.\n");
 749                 usage();
 750         }
 751         if (print_fingerprint || print_bubblebabble)
 752                 do_fingerprint(pw);
 753         if (change_passphrase)
 754                 do_change_passphrase(pw);
 755         if (change_comment)
 756                 do_change_comment(pw);
 757         if (convert_to_ssh2)
 758                 do_convert_to_ssh2(pw);
 759         if (convert_from_ssh2)
 760                 do_convert_from_ssh2(pw);
 761         if (print_public)
 762                 do_print_public(pw);
 763
 764         arc4random_stir();
 765
 766         type = key_type_from_name(key_type_name);
 767         if (type == KEY_UNSPEC) {
 768                 fprintf(stderr, "unknown key type %s\n", key_type_name);
 769                 exit(1);
 770         }
 771         if (!quiet)
 772                 printf("Generating public/private %s key pair.\n", key_type_name);
 773         private = key_generate(type, bits);
 774         if (private == NULL) {
 775                 fprintf(stderr, "key_generate failed");
 776                 exit(1);
 777         }
 778         public  = key_from_private(private);
 779
 780         if (!have_identity)
 781                 ask_filename(pw, "Enter file in which to save the key");
 782
 783         /* Create ~/.ssh directory if it doesn\'t already exist. */
 784         snprintf(dotsshdir, sizeof dotsshdir, "%s/%s", pw->pw_dir, _PATH_SSH_USER_DIR);
 785         if (strstr(identity_file, dotsshdir) != NULL &&
 786             stat(dotsshdir, &st) < 0) {
 787                 if (mkdir(dotsshdir, 0700) < 0)
 788                         error("Could not create directory '%s'.", dotsshdir);
 789                 else if (!quiet)
 790                         printf("Created directory '%s'.\n", dotsshdir);
 791         }
 792         /* If the file already exists, ask the user to confirm. */
 793         if (stat(identity_file, &st) >= 0) {
 794                 char yesno[3];
 795                 printf("%s already exists.\n", identity_file);
 796                 printf("Overwrite (y/n)? ");
 797                 fflush(stdout);
 798                 if (fgets(yesno, sizeof(yesno), stdin) == NULL)
 799                         exit(1);
 800                 if (yesno[0] != 'y' && yesno[0] != 'Y')
 801                         exit(1);
 802         }
 803         /* Ask for a passphrase (twice). */
 804         if (identity_passphrase)
 805                 passphrase1 = xstrdup(identity_passphrase);
 806         else if (identity_new_passphrase)
 807                 passphrase1 = xstrdup(identity_new_passphrase);
 808         else {
 809 passphrase_again:
 810                 passphrase1 =
 811                         read_passphrase("Enter passphrase (empty for no passphrase): ", 1);
 812                 passphrase2 = read_passphrase("Enter same passphrase again: ", 1);
 813                 if (strcmp(passphrase1, passphrase2) != 0) {
 814                         /* The passphrases do not match.  Clear them and retry. */
 815                         memset(passphrase1, 0, strlen(passphrase1));
 816                         memset(passphrase2, 0, strlen(passphrase2));
 817                         xfree(passphrase1);
 818                         xfree(passphrase2);
 819                         printf("Passphrases do not match.  Try again.\n");
 820                         goto passphrase_again;
 821                 }
 822                 /* Clear the other copy of the passphrase. */
 823                 memset(passphrase2, 0, strlen(passphrase2));
 824                 xfree(passphrase2);
 825         }
 826
 827         if (identity_comment) {
 828                 strlcpy(comment, identity_comment, sizeof(comment));
 829         } else {
 830                 /* Create default commend field for the passphrase. */
 831                 snprintf(comment, sizeof comment, "%s@%s", pw->pw_name, hostname);
 832         }
 833
 834         /* Save the key with the given passphrase and comment. */
 835         if (!key_save_private(private, identity_file, passphrase1, comment)) {
 836                 printf("Saving the key failed: %s.\n", identity_file);
 837                 memset(passphrase1, 0, strlen(passphrase1));
 838                 xfree(passphrase1);
 839                 exit(1);
 840         }
 841         /* Clear the passphrase. */
 842         memset(passphrase1, 0, strlen(passphrase1));
 843         xfree(passphrase1);
 844
 845         /* Clear the private key and the random number generator. */
 846         key_free(private);
 847         arc4random_stir();
 848
 849         if (!quiet)
 850                 printf("Your identification has been saved in %s.\n", identity_file);
 851
 852         strlcat(identity_file, ".pub", sizeof(identity_file));
 853         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 854         if (fd == -1) {
 855                 printf("Could not save your public key in %s\n", identity_file);
 856                 exit(1);
 857         }
 858         f = fdopen(fd, "w");
 859         if (f == NULL) {
 860                 printf("fdopen %s failed", identity_file);
 861                 exit(1);
 862         }
 863         if (!key_write(public, f))
 864                 fprintf(stderr, "write key failed");
 865         fprintf(f, " %s\n", comment);
 866         fclose(f);
 867
 868         if (!quiet) {
 869                 char *fp = key_fingerprint(public, SSH_FP_MD5, SSH_FP_HEX);
 870                 printf("Your public key has been saved in %s.\n",
 871                     identity_file);
 872                 printf("The key fingerprint is:\n");
 873                 printf("%s %s\n", fp, comment);
 874                 xfree(fp);
 875         }
 876
 877         key_free(public);
 878         exit(0);
 879 }