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 1.48 2001/03/11 16:39:03 deraadt Exp $");
  16
  17 #include <openssl/evp.h>
  18 #include <openssl/pem.h>
  19
  20 #include "xmalloc.h"
  21 #include "key.h"
  22 #include "authfile.h"
  23 #include "uuencode.h"
  24 #include "buffer.h"
  25 #include "bufaux.h"
  26 #include "pathnames.h"
  27 #include "log.h"
  28 #include "readpass.h"
  29
  30 /* Number of bits in the RSA/DSA key.  This value can be changed on the command line. */
  31 int bits = 1024;
  32
  33 /*
  34  * Flag indicating that we just want to change the passphrase.  This can be
  35  * set on the command line.
  36  */
  37 int change_passphrase = 0;
  38
  39 /*
  40  * Flag indicating that we just want to change the comment.  This can be set
  41  * on the command line.
  42  */
  43 int change_comment = 0;
  44
  45 int quiet = 0;
  46
  47 /* Flag indicating that we just want to see the key fingerprint */
  48 int print_fingerprint = 0;
  49
  50 /* The identity file name, given on the command line or entered by the user. */
  51 char identity_file[1024];
  52 int have_identity = 0;
  53
  54 /* This is set to the passphrase if given on the command line. */
  55 char *identity_passphrase = NULL;
  56
  57 /* This is set to the new passphrase if given on the command line. */
  58 char *identity_new_passphrase = NULL;
  59
  60 /* This is set to the new comment if given on the command line. */
  61 char *identity_comment = NULL;
  62
  63 /* Dump public key file in format used by real and the original SSH 2 */
  64 int convert_to_ssh2 = 0;
  65 int convert_from_ssh2 = 0;
  66 int print_public = 0;
  67 int print_verbose = 0;
  68
  69 /* default to RSA for SSH-1 */
  70 char *key_type_name = "rsa1";
  71
  72 /* argv0 */
  73 #ifdef HAVE___PROGNAME
  74 extern char *__progname;
  75 #else
  76 char *__progname;
  77 #endif
  78
  79 char hostname[MAXHOSTNAMELEN];
  80
  81 void
  82 ask_filename(struct passwd *pw, const char *prompt)
  83 {
  84         char buf[1024];
  85         char *name = NULL;
  86
  87         switch (key_type_from_name(key_type_name)) {
  88         case KEY_RSA1:
  89                 name = _PATH_SSH_CLIENT_IDENTITY;
  90                 break;
  91         case KEY_DSA:
  92                 name = _PATH_SSH_CLIENT_ID_DSA;
  93                 break;
  94         case KEY_RSA:
  95                 name = _PATH_SSH_CLIENT_ID_RSA;
  96                 break;
  97         default:
  98                 fprintf(stderr, "bad key type");
  99                 exit(1);
 100                 break;
 101         }
 102         snprintf(identity_file, sizeof(identity_file), "%s/%s", pw->pw_dir, name);
 103         fprintf(stderr, "%s (%s): ", prompt, identity_file);
 104         fflush(stderr);
 105         if (fgets(buf, sizeof(buf), stdin) == NULL)
 106                 exit(1);
 107         if (strchr(buf, '\n'))
 108                 *strchr(buf, '\n') = 0;
 109         if (strcmp(buf, "") != 0)
 110                 strlcpy(identity_file, buf, sizeof(identity_file));
 111         have_identity = 1;
 112 }
 113
 114 int
 115 try_load_key(char *filename, Key *k)
 116 {
 117         int success = 1;
 118         if (!load_private_key(filename, "", k, NULL)) {
 119                 char *pass = read_passphrase("Enter passphrase: ", 1);
 120                 if (!load_private_key(filename, pass, k, NULL)) {
 121                         success = 0;
 122                 }
 123                 memset(pass, 0, strlen(pass));
 124                 xfree(pass);
 125         }
 126         return success;
 127 }
 128
 129 #define SSH_COM_PUBLIC_BEGIN            "---- BEGIN SSH2 PUBLIC KEY ----"
 130 #define SSH_COM_PUBLIC_END              "---- END SSH2 PUBLIC KEY ----"
 131 #define SSH_COM_PRIVATE_BEGIN           "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----"
 132 #define SSH_COM_PRIVATE_KEY_MAGIC       0x3f6ff9eb
 133
 134 void
 135 do_convert_to_ssh2(struct passwd *pw)
 136 {
 137         Key *k;
 138         int len;
 139         u_char *blob;
 140         struct stat st;
 141
 142         if (!have_identity)
 143                 ask_filename(pw, "Enter file in which the key is");
 144         if (stat(identity_file, &st) < 0) {
 145                 perror(identity_file);
 146                 exit(1);
 147         }
 148         k = key_new(KEY_UNSPEC);
 149         if (!try_load_key(identity_file, k)) {
 150                 fprintf(stderr, "load failed\n");
 151                 exit(1);
 152         }
 153         key_to_blob(k, &blob, &len);
 154         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_BEGIN);
 155         fprintf(stdout,
 156             "Comment: \"%d-bit %s, converted from OpenSSH by %s@%s\"\n",
 157             key_size(k), key_type(k),
 158             pw->pw_name, hostname);
 159         dump_base64(stdout, blob, len);
 160         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_END);
 161         key_free(k);
 162         xfree(blob);
 163         exit(0);
 164 }
 165
 166 void
 167 buffer_get_bignum_bits(Buffer *b, BIGNUM *value)
 168 {
 169         int bits = buffer_get_int(b);
 170         int bytes = (bits + 7) / 8;
 171         if (buffer_len(b) < bytes)
 172                 fatal("buffer_get_bignum_bits: input buffer too small");
 173         BN_bin2bn((u_char *)buffer_ptr(b), bytes, value);
 174         buffer_consume(b, bytes);
 175 }
 176
 177 Key *
 178 do_convert_private_ssh2_from_blob(char *blob, int blen)
 179 {
 180         Buffer b;
 181         DSA *dsa;
 182         Key *key = NULL;
 183         int ignore, magic, rlen;
 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         xfree(type);
 202
 203         if (strcmp(cipher, "none") != 0) {
 204                 error("unsupported cipher %s", cipher);
 205                 xfree(cipher);
 206                 buffer_free(&b);
 207                 return NULL;
 208         }
 209         xfree(cipher);
 210
 211         key = key_new(KEY_DSA);
 212         dsa = key->dsa;
 213         dsa->priv_key = BN_new();
 214         if (dsa->priv_key == NULL) {
 215                 error("alloc priv_key failed");
 216                 key_free(key);
 217                 return NULL;
 218         }
 219         buffer_get_bignum_bits(&b, dsa->p);
 220         buffer_get_bignum_bits(&b, dsa->g);
 221         buffer_get_bignum_bits(&b, dsa->q);
 222         buffer_get_bignum_bits(&b, dsa->pub_key);
 223         buffer_get_bignum_bits(&b, dsa->priv_key);
 224         rlen = buffer_len(&b);
 225         if(rlen != 0)
 226                 error("do_convert_private_ssh2_from_blob: remaining bytes in key blob %d", rlen);
 227         buffer_free(&b);
 228         return key;
 229 }
 230
 231 void
 232 do_convert_from_ssh2(struct passwd *pw)
 233 {
 234         Key *k;
 235         int blen;
 236         char line[1024], *p;
 237         char blob[8096];
 238         char encoded[8096];
 239         struct stat st;
 240         int escaped = 0, private = 0, ok;
 241         FILE *fp;
 242
 243         if (!have_identity)
 244                 ask_filename(pw, "Enter file in which the key is");
 245         if (stat(identity_file, &st) < 0) {
 246                 perror(identity_file);
 247                 exit(1);
 248         }
 249         fp = fopen(identity_file, "r");
 250         if (fp == NULL) {
 251                 perror(identity_file);
 252                 exit(1);
 253         }
 254         encoded[0] = '\0';
 255         while (fgets(line, sizeof(line), fp)) {
 256                 if (!(p = strchr(line, '\n'))) {
 257                         fprintf(stderr, "input line too long.\n");
 258                         exit(1);
 259                 }
 260                 if (p > line && p[-1] == '\\')
 261                         escaped++;
 262                 if (strncmp(line, "----", 4) == 0 ||
 263                     strstr(line, ": ") != NULL) {
 264                         if (strstr(line, SSH_COM_PRIVATE_BEGIN) != NULL)
 265                                 private = 1;
 266                         fprintf(stderr, "ignore: %s", line);
 267                         continue;
 268                 }
 269                 if (escaped) {
 270                         escaped--;
 271                         fprintf(stderr, "escaped: %s", line);
 272                         continue;
 273                 }
 274                 *p = '\0';
 275                 strlcat(encoded, line, sizeof(encoded));
 276         }
 277         blen = uudecode(encoded, (u_char *)blob, sizeof(blob));
 278         if (blen < 0) {
 279                 fprintf(stderr, "uudecode failed.\n");
 280                 exit(1);
 281         }
 282         k = private ?
 283             do_convert_private_ssh2_from_blob(blob, blen) :
 284             key_from_blob(blob, blen);
 285         if (k == NULL) {
 286                 fprintf(stderr, "decode blob failed.\n");
 287                 exit(1);
 288         }
 289         ok = private ?
 290             PEM_write_DSAPrivateKey(stdout, k->dsa, NULL, NULL, 0, NULL, NULL) :
 291             key_write(k, stdout);
 292         if (!ok) {
 293                 fprintf(stderr, "key write failed");
 294                 exit(1);
 295         }
 296         key_free(k);
 297         fprintf(stdout, "\n");
 298         fclose(fp);
 299         exit(0);
 300 }
 301
 302 void
 303 do_print_public(struct passwd *pw)
 304 {
 305         Key *k;
 306         struct stat st;
 307
 308         if (!have_identity)
 309                 ask_filename(pw, "Enter file in which the key is");
 310         if (stat(identity_file, &st) < 0) {
 311                 perror(identity_file);
 312                 exit(1);
 313         }
 314         k = key_new(KEY_UNSPEC);
 315         if (!try_load_key(identity_file, k)) {
 316                 fprintf(stderr, "load failed\n");
 317                 exit(1);
 318         }
 319         if (!key_write(k, stdout))
 320                 fprintf(stderr, "key_write failed");
 321         key_free(k);
 322         fprintf(stdout, "\n");
 323         exit(0);
 324 }
 325
 326 void
 327 do_fingerprint(struct passwd *pw)
 328 {
 329
 330         FILE *f;
 331         Key *public;
 332         char *comment = NULL, *cp, *ep, line[16*1024];
 333         int i, skip = 0, num = 1, invalid = 1, success = 0;
 334         struct stat st;
 335
 336         if (!have_identity)
 337                 ask_filename(pw, "Enter file in which the key is");
 338         if (stat(identity_file, &st) < 0) {
 339                 perror(identity_file);
 340                 exit(1);
 341         }
 342         public = key_new(KEY_RSA1);
 343         if (load_public_key(identity_file, public, &comment)) {
 344                 success = 1;
 345         } else {
 346                 key_free(public);
 347                 public = key_new(KEY_UNSPEC);
 348                 if (try_load_public_key(identity_file, public, &comment))
 349                         success = 1;
 350                 else
 351                         debug("try_load_public_key KEY_UNSPEC failed");
 352         }
 353         if (success) {
 354                 char *digest_md5, *digest_bubblebabble;
 355
 356                 digest_md5 = key_fingerprint_ex(public, SSH_FP_MD5, SSH_FP_HEX);
 357                 digest_bubblebabble = key_fingerprint_ex(public, SSH_FP_SHA1,
 358                     SSH_FP_BUBBLEBABBLE);
 359
 360                 if (print_verbose) {
 361                         printf("comment:      %s\n", comment);
 362                         printf("size:         %d\n", key_size(public));
 363                         printf("md5:          %s\n", digest_md5);
 364                         printf("bubblebabble: %s\n", digest_bubblebabble);
 365                 } else {
 366                         printf("%d %s %s\n", key_size(public), digest_md5, comment);
 367                 }
 368
 369                 key_free(public);
 370                 xfree(comment);
 371                 xfree(digest_md5);
 372                 xfree(digest_bubblebabble);
 373
 374                 exit(0);
 375         }
 376
 377         f = fopen(identity_file, "r");
 378         if (f != NULL) {
 379                 while (fgets(line, sizeof(line), f)) {
 380                         i = strlen(line) - 1;
 381                         if (line[i] != '\n') {
 382                                 error("line %d too long: %.40s...", num, line);
 383                                 skip = 1;
 384                                 continue;
 385                         }
 386                         num++;
 387                         if (skip) {
 388                                 skip = 0;
 389                                 continue;
 390                         }
 391                         line[i] = '\0';
 392
 393                         /* Skip leading whitespace, empty and comment lines. */
 394                         for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
 395                                 ;
 396                         if (!*cp || *cp == '\n' || *cp == '#')
 397                                 continue ;
 398                         i = strtol(cp, &ep, 10);
 399                         if (i == 0 || ep == NULL || (*ep != ' ' && *ep != '\t')) {
 400                                 int quoted = 0;
 401                                 comment = cp;
 402                                 for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
 403                                         if (*cp == '\\' && cp[1] == '"')
 404                                                 cp++;   /* Skip both */
 405                                         else if (*cp == '"')
 406                                                 quoted = !quoted;
 407                                 }
 408                                 if (!*cp)
 409                                         continue;
 410                                 *cp++ = '\0';
 411                         }
 412                         ep = cp;
 413                         public = key_new(KEY_RSA1);
 414                         if (key_read(public, &cp) != 1) {
 415                                 cp = ep;
 416                                 key_free(public);
 417                                 public = key_new(KEY_UNSPEC);
 418                                 if (key_read(public, &cp) != 1) {
 419                                         key_free(public);
 420                                         continue;
 421                                 }
 422                         }
 423                         comment = *cp ? cp : comment;
 424                         printf("%d %s %s\n", key_size(public),
 425                             key_fingerprint(public),
 426                             comment ? comment : "no comment");
 427                         invalid = 0;
 428                 }
 429                 fclose(f);
 430         }
 431         key_free(public);
 432         if (invalid) {
 433                 printf("%s is not a valid key file.\n", identity_file);
 434                 exit(1);
 435         }
 436         exit(0);
 437 }
 438
 439 /*
 440  * Perform changing a passphrase.  The argument is the passwd structure
 441  * for the current user.
 442  */
 443 void
 444 do_change_passphrase(struct passwd *pw)
 445 {
 446         char *comment;
 447         char *old_passphrase, *passphrase1, *passphrase2;
 448         struct stat st;
 449         Key *private;
 450         Key *public;
 451         int type = KEY_RSA1;
 452
 453         if (!have_identity)
 454                 ask_filename(pw, "Enter file in which the key is");
 455         if (stat(identity_file, &st) < 0) {
 456                 perror(identity_file);
 457                 exit(1);
 458         }
 459         public = key_new(type);
 460         if (!load_public_key(identity_file, public, NULL)) {
 461                 type = KEY_UNSPEC;
 462         } else {
 463                 /* Clear the public key since we are just about to load the whole file. */
 464                 key_free(public);
 465         }
 466         /* Try to load the file with empty passphrase. */
 467         private = key_new(type);
 468         if (!load_private_key(identity_file, "", private, &comment)) {
 469                 if (identity_passphrase)
 470                         old_passphrase = xstrdup(identity_passphrase);
 471                 else
 472                         old_passphrase = read_passphrase("Enter old passphrase: ", 1);
 473                 if (!load_private_key(identity_file, old_passphrase, private, &comment)) {
 474                         memset(old_passphrase, 0, strlen(old_passphrase));
 475                         xfree(old_passphrase);
 476                         printf("Bad passphrase.\n");
 477                         exit(1);
 478                 }
 479                 memset(old_passphrase, 0, strlen(old_passphrase));
 480                 xfree(old_passphrase);
 481         }
 482         printf("Key has comment '%s'\n", comment);
 483
 484         /* Ask the new passphrase (twice). */
 485         if (identity_new_passphrase) {
 486                 passphrase1 = xstrdup(identity_new_passphrase);
 487                 passphrase2 = NULL;
 488         } else {
 489                 passphrase1 =
 490                         read_passphrase("Enter new passphrase (empty for no passphrase): ", 1);
 491                 passphrase2 = read_passphrase("Enter same passphrase again: ", 1);
 492
 493                 /* Verify that they are the same. */
 494                 if (strcmp(passphrase1, passphrase2) != 0) {
 495                         memset(passphrase1, 0, strlen(passphrase1));
 496                         memset(passphrase2, 0, strlen(passphrase2));
 497                         xfree(passphrase1);
 498                         xfree(passphrase2);
 499                         printf("Pass phrases do not match.  Try again.\n");
 500                         exit(1);
 501                 }
 502                 /* Destroy the other copy. */
 503                 memset(passphrase2, 0, strlen(passphrase2));
 504                 xfree(passphrase2);
 505         }
 506
 507         /* Save the file using the new passphrase. */
 508         if (!save_private_key(identity_file, passphrase1, private, comment)) {
 509                 printf("Saving the key failed: %s: %s.\n",
 510                        identity_file, strerror(errno));
 511                 memset(passphrase1, 0, strlen(passphrase1));
 512                 xfree(passphrase1);
 513                 key_free(private);
 514                 xfree(comment);
 515                 exit(1);
 516         }
 517         /* Destroy the passphrase and the copy of the key in memory. */
 518         memset(passphrase1, 0, strlen(passphrase1));
 519         xfree(passphrase1);
 520         key_free(private);               /* Destroys contents */
 521         xfree(comment);
 522
 523         printf("Your identification has been saved with the new passphrase.\n");
 524         exit(0);
 525 }
 526
 527 /*
 528  * Change the comment of a private key file.
 529  */
 530 void
 531 do_change_comment(struct passwd *pw)
 532 {
 533         char new_comment[1024], *comment, *passphrase;
 534         Key *private, *public;
 535         struct stat st;
 536         FILE *f;
 537         int fd;
 538
 539         if (!have_identity)
 540                 ask_filename(pw, "Enter file in which the key is");
 541         if (stat(identity_file, &st) < 0) {
 542                 perror(identity_file);
 543                 exit(1);
 544         }
 545         /*
 546          * Try to load the public key from the file the verify that it is
 547          * readable and of the proper format.
 548          */
 549         public = key_new(KEY_RSA1);
 550         if (!load_public_key(identity_file, public, NULL)) {
 551                 printf("%s is not a valid key file.\n", identity_file);
 552                 printf("Comments are only supported in RSA1 keys\n");
 553                 exit(1);
 554         }
 555
 556         private = key_new(KEY_RSA1);
 557         if (load_private_key(identity_file, "", private, &comment))
 558                 passphrase = xstrdup("");
 559         else {
 560                 if (identity_passphrase)
 561                         passphrase = xstrdup(identity_passphrase);
 562                 else if (identity_new_passphrase)
 563                         passphrase = xstrdup(identity_new_passphrase);
 564                 else
 565                         passphrase = read_passphrase("Enter passphrase: ", 1);
 566                 /* Try to load using the passphrase. */
 567                 if (!load_private_key(identity_file, passphrase, private, &comment)) {
 568                         memset(passphrase, 0, strlen(passphrase));
 569                         xfree(passphrase);
 570                         printf("Bad passphrase.\n");
 571                         exit(1);
 572                 }
 573         }
 574         printf("Key now has comment '%s'\n", comment);
 575
 576         if (identity_comment) {
 577                 strlcpy(new_comment, identity_comment, sizeof(new_comment));
 578         } else {
 579                 printf("Enter new comment: ");
 580                 fflush(stdout);
 581                 if (!fgets(new_comment, sizeof(new_comment), stdin)) {
 582                         memset(passphrase, 0, strlen(passphrase));
 583                         key_free(private);
 584                         exit(1);
 585                 }
 586                 if (strchr(new_comment, '\n'))
 587                         *strchr(new_comment, '\n') = 0;
 588         }
 589
 590         /* Save the file using the new passphrase. */
 591         if (!save_private_key(identity_file, passphrase, private, new_comment)) {
 592                 printf("Saving the key failed: %s: %s.\n",
 593                        identity_file, strerror(errno));
 594                 memset(passphrase, 0, strlen(passphrase));
 595                 xfree(passphrase);
 596                 key_free(private);
 597                 xfree(comment);
 598                 exit(1);
 599         }
 600         memset(passphrase, 0, strlen(passphrase));
 601         xfree(passphrase);
 602         key_free(private);
 603
 604         strlcat(identity_file, ".pub", sizeof(identity_file));
 605         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 606         if (fd == -1) {
 607                 printf("Could not save your public key in %s\n", identity_file);
 608                 exit(1);
 609         }
 610         f = fdopen(fd, "w");
 611         if (f == NULL) {
 612                 printf("fdopen %s failed", identity_file);
 613                 exit(1);
 614         }
 615         if (!key_write(public, f))
 616                 fprintf(stderr, "write key failed");
 617         key_free(public);
 618         fprintf(f, " %s\n", new_comment);
 619         fclose(f);
 620
 621         xfree(comment);
 622
 623         printf("The comment in your key file has been changed.\n");
 624         exit(0);
 625 }
 626
 627 void
 628 usage(void)
 629 {
 630         printf("Usage: %s [-lpqxXyc] [-t type] [-b bits] [-f file] [-C comment] "
 631             "[-N new-pass] [-P pass]\n", __progname);
 632         exit(1);
 633 }
 634
 635 /*
 636  * Main program for key management.
 637  */
 638 int
 639 main(int ac, char **av)
 640 {
 641         char dotsshdir[16 * 1024], comment[1024], *passphrase1, *passphrase2;
 642         Key *private, *public;
 643         struct passwd *pw;
 644         int opt, type, fd;
 645         struct stat st;
 646         FILE *f;
 647
 648         extern int optind;
 649         extern char *optarg;
 650
 651         __progname = get_progname(av[0]);
 652         init_rng();
 653
 654         SSLeay_add_all_algorithms();
 655
 656         /* we need this for the home * directory.  */
 657         pw = getpwuid(getuid());
 658         if (!pw) {
 659                 printf("You don't exist, go away!\n");
 660                 exit(1);
 661         }
 662         if (gethostname(hostname, sizeof(hostname)) < 0) {
 663                 perror("gethostname");
 664                 exit(1);
 665         }
 666
 667         while ((opt = getopt(ac, av, "dqpclRxXyvb:f:t:P:N:C:")) != -1) {
 668                 switch (opt) {
 669                 case 'b':
 670                         bits = atoi(optarg);
 671                         if (bits < 512 || bits > 32768) {
 672                                 printf("Bits has bad value.\n");
 673                                 exit(1);
 674                         }
 675                         break;
 676
 677                 case 'l':
 678                         print_fingerprint = 1;
 679                         break;
 680
 681                 case 'p':
 682                         change_passphrase = 1;
 683                         break;
 684
 685                 case 'c':
 686                         change_comment = 1;
 687                         break;
 688
 689                 case 'f':
 690                         strlcpy(identity_file, optarg, sizeof(identity_file));
 691                         have_identity = 1;
 692                         break;
 693
 694                 case 'P':
 695                         identity_passphrase = optarg;
 696                         break;
 697
 698                 case 'N':
 699                         identity_new_passphrase = optarg;
 700                         break;
 701
 702                 case 'C':
 703                         identity_comment = optarg;
 704                         break;
 705
 706                 case 'q':
 707                         quiet = 1;
 708                         break;
 709
 710                 case 'R':
 711                         /* unused */
 712                         exit(0);
 713                         break;
 714
 715                 case 'x':
 716                         convert_to_ssh2 = 1;
 717                         break;
 718
 719                 case 'X':
 720                         convert_from_ssh2 = 1;
 721                         break;
 722
 723                 case 'y':
 724                         print_public = 1;
 725                         break;
 726
 727                 case 'v':
 728                         print_verbose = 1;
 729                         break;
 730
 731                 case 'd':
 732                         key_type_name = "dsa";
 733                         break;
 734
 735                 case 't':
 736                         key_type_name = optarg;
 737                         break;
 738
 739                 case '?':
 740                 default:
 741                         usage();
 742                 }
 743         }
 744         if (optind < ac) {
 745                 printf("Too many arguments.\n");
 746                 usage();
 747         }
 748         if (change_passphrase && change_comment) {
 749                 printf("Can only have one of -p and -c.\n");
 750                 usage();
 751         }
 752         if (print_fingerprint)
 753                 do_fingerprint(pw);
 754         if (change_passphrase)
 755                 do_change_passphrase(pw);
 756         if (change_comment)
 757                 do_change_comment(pw);
 758         if (convert_to_ssh2)
 759                 do_convert_to_ssh2(pw);
 760         if (convert_from_ssh2)
 761                 do_convert_from_ssh2(pw);
 762         if (print_public)
 763                 do_print_public(pw);
 764
 765         arc4random_stir();
 766
 767         type = key_type_from_name(key_type_name);
 768         if (type == KEY_UNSPEC) {
 769                 fprintf(stderr, "unknown key type %s\n", key_type_name);
 770                 exit(1);
 771         }
 772         if (!quiet)
 773                 printf("Generating public/private %s key pair.\n", key_type_name);
 774         private = key_generate(type, bits);
 775         if (private == NULL) {
 776                 fprintf(stderr, "key_generate failed");
 777                 exit(1);
 778         }
 779         public  = key_from_private(private);
 780
 781         if (!have_identity)
 782                 ask_filename(pw, "Enter file in which to save the key");
 783
 784         /* Create ~/.ssh directory if it doesn\'t already exist. */
 785         snprintf(dotsshdir, sizeof dotsshdir, "%s/%s", pw->pw_dir, _PATH_SSH_USER_DIR);
 786         if (strstr(identity_file, dotsshdir) != NULL &&
 787             stat(dotsshdir, &st) < 0) {
 788                 if (mkdir(dotsshdir, 0700) < 0)
 789                         error("Could not create directory '%s'.", dotsshdir);
 790                 else if (!quiet)
 791                         printf("Created directory '%s'.\n", dotsshdir);
 792         }
 793         /* If the file already exists, ask the user to confirm. */
 794         if (stat(identity_file, &st) >= 0) {
 795                 char yesno[3];
 796                 printf("%s already exists.\n", identity_file);
 797                 printf("Overwrite (y/n)? ");
 798                 fflush(stdout);
 799                 if (fgets(yesno, sizeof(yesno), stdin) == NULL)
 800                         exit(1);
 801                 if (yesno[0] != 'y' && yesno[0] != 'Y')
 802                         exit(1);
 803         }
 804         /* Ask for a passphrase (twice). */
 805         if (identity_passphrase)
 806                 passphrase1 = xstrdup(identity_passphrase);
 807         else if (identity_new_passphrase)
 808                 passphrase1 = xstrdup(identity_new_passphrase);
 809         else {
 810 passphrase_again:
 811                 passphrase1 =
 812                         read_passphrase("Enter passphrase (empty for no passphrase): ", 1);
 813                 passphrase2 = read_passphrase("Enter same passphrase again: ", 1);
 814                 if (strcmp(passphrase1, passphrase2) != 0) {
 815                         /* The passphrases do not match.  Clear them and retry. */
 816                         memset(passphrase1, 0, strlen(passphrase1));
 817                         memset(passphrase2, 0, strlen(passphrase2));
 818                         xfree(passphrase1);
 819                         xfree(passphrase2);
 820                         printf("Passphrases do not match.  Try again.\n");
 821                         goto passphrase_again;
 822                 }
 823                 /* Clear the other copy of the passphrase. */
 824                 memset(passphrase2, 0, strlen(passphrase2));
 825                 xfree(passphrase2);
 826         }
 827
 828         if (identity_comment) {
 829                 strlcpy(comment, identity_comment, sizeof(comment));
 830         } else {
 831                 /* Create default commend field for the passphrase. */
 832                 snprintf(comment, sizeof comment, "%s@%s", pw->pw_name, hostname);
 833         }
 834
 835         /* Save the key with the given passphrase and comment. */
 836         if (!save_private_key(identity_file, passphrase1, private, comment)) {
 837                 printf("Saving the key failed: %s: %s.\n",
 838                     identity_file, strerror(errno));
 839                 memset(passphrase1, 0, strlen(passphrase1));
 840                 xfree(passphrase1);
 841                 exit(1);
 842         }
 843         /* Clear the passphrase. */
 844         memset(passphrase1, 0, strlen(passphrase1));
 845         xfree(passphrase1);
 846
 847         /* Clear the private key and the random number generator. */
 848         key_free(private);
 849         arc4random_stir();
 850
 851         if (!quiet)
 852                 printf("Your identification has been saved in %s.\n", identity_file);
 853
 854         strlcat(identity_file, ".pub", sizeof(identity_file));
 855         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 856         if (fd == -1) {
 857                 printf("Could not save your public key in %s\n", identity_file);
 858                 exit(1);
 859         }
 860         f = fdopen(fd, "w");
 861         if (f == NULL) {
 862                 printf("fdopen %s failed", identity_file);
 863                 exit(1);
 864         }
 865         if (!key_write(public, f))
 866                 fprintf(stderr, "write key failed");
 867         fprintf(f, " %s\n", comment);
 868         fclose(f);
 869
 870         if (!quiet) {
 871                 printf("Your public key has been saved in %s.\n",
 872                     identity_file);
 873                 printf("The key fingerprint is:\n");
 874                 printf("%s %s\n", key_fingerprint(public), comment);
 875         }
 876
 877         key_free(public);
 878         exit(0);
 879 }