crypto/openssh-3.8.1p1/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 1.113 2003/12/22 09:16:58 djm 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 #include "moduli.h"
  31
  32 #ifdef SMARTCARD
  33 #include "scard.h"
  34 #endif
  35 #include "dns.h"
  36
  37 /* Number of bits in the RSA/DSA key.  This value can be changed on the command line. */
  38 int bits = 1024;
  39
  40 /*
  41  * Flag indicating that we just want to change the passphrase.  This can be
  42  * set on the command line.
  43  */
  44 int change_passphrase = 0;
  45
  46 /*
  47  * Flag indicating that we just want to change the comment.  This can be set
  48  * on the command line.
  49  */
  50 int change_comment = 0;
  51
  52 int quiet = 0;
  53
  54 /* Flag indicating that we just want to see the key fingerprint */
  55 int print_fingerprint = 0;
  56 int print_bubblebabble = 0;
  57
  58 /* The identity file name, given on the command line or entered by the user. */
  59 char identity_file[1024];
  60 int have_identity = 0;
  61
  62 /* This is set to the passphrase if given on the command line. */
  63 char *identity_passphrase = NULL;
  64
  65 /* This is set to the new passphrase if given on the command line. */
  66 char *identity_new_passphrase = NULL;
  67
  68 /* This is set to the new comment if given on the command line. */
  69 char *identity_comment = NULL;
  70
  71 /* Dump public key file in format used by real and the original SSH 2 */
  72 int convert_to_ssh2 = 0;
  73 int convert_from_ssh2 = 0;
  74 int print_public = 0;
  75 int print_generic = 0;
  76
  77 char *key_type_name = NULL;
  78
  79 /* argv0 */
  80 #ifdef HAVE___PROGNAME
  81 extern char *__progname;
  82 #else
  83 char *__progname;
  84 #endif
  85
  86 char hostname[MAXHOSTNAMELEN];
  87
  88 static void
  89 ask_filename(struct passwd *pw, const char *prompt)
  90 {
  91         char buf[1024];
  92         char *name = NULL;
  93
  94         if (key_type_name == NULL)
  95                 name = _PATH_SSH_CLIENT_ID_RSA;
  96         else
  97                 switch (key_type_from_name(key_type_name)) {
  98                 case KEY_RSA1:
  99                         name = _PATH_SSH_CLIENT_IDENTITY;
 100                         break;
 101                 case KEY_DSA:
 102                         name = _PATH_SSH_CLIENT_ID_DSA;
 103                         break;
 104                 case KEY_RSA:
 105                         name = _PATH_SSH_CLIENT_ID_RSA;
 106                         break;
 107                 default:
 108                         fprintf(stderr, "bad key type");
 109                         exit(1);
 110                         break;
 111                 }
 112
 113         snprintf(identity_file, sizeof(identity_file), "%s/%s", pw->pw_dir, name);
 114         fprintf(stderr, "%s (%s): ", prompt, identity_file);
 115         if (fgets(buf, sizeof(buf), stdin) == NULL)
 116                 exit(1);
 117         if (strchr(buf, '\n'))
 118                 *strchr(buf, '\n') = 0;
 119         if (strcmp(buf, "") != 0)
 120                 strlcpy(identity_file, buf, sizeof(identity_file));
 121         have_identity = 1;
 122 }
 123
 124 static Key *
 125 load_identity(char *filename)
 126 {
 127         char *pass;
 128         Key *prv;
 129
 130         prv = key_load_private(filename, "", NULL);
 131         if (prv == NULL) {
 132                 if (identity_passphrase)
 133                         pass = xstrdup(identity_passphrase);
 134                 else
 135                         pass = read_passphrase("Enter passphrase: ",
 136                             RP_ALLOW_STDIN);
 137                 prv = key_load_private(filename, pass, NULL);
 138                 memset(pass, 0, strlen(pass));
 139                 xfree(pass);
 140         }
 141         return prv;
 142 }
 143
 144 #define SSH_COM_PUBLIC_BEGIN            "---- BEGIN SSH2 PUBLIC KEY ----"
 145 #define SSH_COM_PUBLIC_END              "---- END SSH2 PUBLIC KEY ----"
 146 #define SSH_COM_PRIVATE_BEGIN           "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----"
 147 #define SSH_COM_PRIVATE_KEY_MAGIC       0x3f6ff9eb
 148
 149 static void
 150 do_convert_to_ssh2(struct passwd *pw)
 151 {
 152         Key *k;
 153         u_int len;
 154         u_char *blob;
 155         struct stat st;
 156
 157         if (!have_identity)
 158                 ask_filename(pw, "Enter file in which the key is");
 159         if (stat(identity_file, &st) < 0) {
 160                 perror(identity_file);
 161                 exit(1);
 162         }
 163         if ((k = key_load_public(identity_file, NULL)) == NULL) {
 164                 if ((k = load_identity(identity_file)) == NULL) {
 165                         fprintf(stderr, "load failed\n");
 166                         exit(1);
 167                 }
 168         }
 169         if (k->type == KEY_RSA1) {
 170                 fprintf(stderr, "version 1 keys are not supported\n");
 171                 exit(1);
 172         }
 173         if (key_to_blob(k, &blob, &len) <= 0) {
 174                 fprintf(stderr, "key_to_blob failed\n");
 175                 exit(1);
 176         }
 177         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_BEGIN);
 178         fprintf(stdout,
 179             "Comment: \"%u-bit %s, converted from OpenSSH by %s@%s\"\n",
 180             key_size(k), key_type(k),
 181             pw->pw_name, hostname);
 182         dump_base64(stdout, blob, len);
 183         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_END);
 184         key_free(k);
 185         xfree(blob);
 186         exit(0);
 187 }
 188
 189 static void
 190 buffer_get_bignum_bits(Buffer *b, BIGNUM *value)
 191 {
 192         u_int bits = buffer_get_int(b);
 193         u_int bytes = (bits + 7) / 8;
 194
 195         if (buffer_len(b) < bytes)
 196                 fatal("buffer_get_bignum_bits: input buffer too small: "
 197                     "need %d have %d", bytes, buffer_len(b));
 198         BN_bin2bn(buffer_ptr(b), bytes, value);
 199         buffer_consume(b, bytes);
 200 }
 201
 202 static Key *
 203 do_convert_private_ssh2_from_blob(u_char *blob, u_int blen)
 204 {
 205         Buffer b;
 206         Key *key = NULL;
 207         char *type, *cipher;
 208         u_char *sig, data[] = "abcde12345";
 209         int magic, rlen, ktype, i1, i2, i3, i4;
 210         u_int slen;
 211         u_long e;
 212
 213         buffer_init(&b);
 214         buffer_append(&b, blob, blen);
 215
 216         magic  = buffer_get_int(&b);
 217         if (magic != SSH_COM_PRIVATE_KEY_MAGIC) {
 218                 error("bad magic 0x%x != 0x%x", magic, SSH_COM_PRIVATE_KEY_MAGIC);
 219                 buffer_free(&b);
 220                 return NULL;
 221         }
 222         i1 = buffer_get_int(&b);
 223         type   = buffer_get_string(&b, NULL);
 224         cipher = buffer_get_string(&b, NULL);
 225         i2 = buffer_get_int(&b);
 226         i3 = buffer_get_int(&b);
 227         i4 = buffer_get_int(&b);
 228         debug("ignore (%d %d %d %d)", i1,i2,i3,i4);
 229         if (strcmp(cipher, "none") != 0) {
 230                 error("unsupported cipher %s", cipher);
 231                 xfree(cipher);
 232                 buffer_free(&b);
 233                 xfree(type);
 234                 return NULL;
 235         }
 236         xfree(cipher);
 237
 238         if (strstr(type, "dsa")) {
 239                 ktype = KEY_DSA;
 240         } else if (strstr(type, "rsa")) {
 241                 ktype = KEY_RSA;
 242         } else {
 243                 xfree(type);
 244                 return NULL;
 245         }
 246         key = key_new_private(ktype);
 247         xfree(type);
 248
 249         switch (key->type) {
 250         case KEY_DSA:
 251                 buffer_get_bignum_bits(&b, key->dsa->p);
 252                 buffer_get_bignum_bits(&b, key->dsa->g);
 253                 buffer_get_bignum_bits(&b, key->dsa->q);
 254                 buffer_get_bignum_bits(&b, key->dsa->pub_key);
 255                 buffer_get_bignum_bits(&b, key->dsa->priv_key);
 256                 break;
 257         case KEY_RSA:
 258                 e  = buffer_get_char(&b);
 259                 debug("e %lx", e);
 260                 if (e < 30) {
 261                         e <<= 8;
 262                         e += buffer_get_char(&b);
 263                         debug("e %lx", e);
 264                         e <<= 8;
 265                         e += buffer_get_char(&b);
 266                         debug("e %lx", e);
 267                 }
 268                 if (!BN_set_word(key->rsa->e, e)) {
 269                         buffer_free(&b);
 270                         key_free(key);
 271                         return NULL;
 272                 }
 273                 buffer_get_bignum_bits(&b, key->rsa->d);
 274                 buffer_get_bignum_bits(&b, key->rsa->n);
 275                 buffer_get_bignum_bits(&b, key->rsa->iqmp);
 276                 buffer_get_bignum_bits(&b, key->rsa->q);
 277                 buffer_get_bignum_bits(&b, key->rsa->p);
 278                 rsa_generate_additional_parameters(key->rsa);
 279                 break;
 280         }
 281         rlen = buffer_len(&b);
 282         if (rlen != 0)
 283                 error("do_convert_private_ssh2_from_blob: "
 284                     "remaining bytes in key blob %d", rlen);
 285         buffer_free(&b);
 286
 287         /* try the key */
 288         key_sign(key, &sig, &slen, data, sizeof(data));
 289         key_verify(key, sig, slen, data, sizeof(data));
 290         xfree(sig);
 291         return key;
 292 }
 293
 294 static void
 295 do_convert_from_ssh2(struct passwd *pw)
 296 {
 297         Key *k;
 298         int blen;
 299         u_int len;
 300         char line[1024], *p;
 301         u_char blob[8096];
 302         char encoded[8096];
 303         struct stat st;
 304         int escaped = 0, private = 0, ok;
 305         FILE *fp;
 306
 307         if (!have_identity)
 308                 ask_filename(pw, "Enter file in which the key is");
 309         if (stat(identity_file, &st) < 0) {
 310                 perror(identity_file);
 311                 exit(1);
 312         }
 313         fp = fopen(identity_file, "r");
 314         if (fp == NULL) {
 315                 perror(identity_file);
 316                 exit(1);
 317         }
 318         encoded[0] = '\0';
 319         while (fgets(line, sizeof(line), fp)) {
 320                 if (!(p = strchr(line, '\n'))) {
 321                         fprintf(stderr, "input line too long.\n");
 322                         exit(1);
 323                 }
 324                 if (p > line && p[-1] == '\\')
 325                         escaped++;
 326                 if (strncmp(line, "----", 4) == 0 ||
 327                     strstr(line, ": ") != NULL) {
 328                         if (strstr(line, SSH_COM_PRIVATE_BEGIN) != NULL)
 329                                 private = 1;
 330                         if (strstr(line, " END ") != NULL) {
 331                                 break;
 332                         }
 333                         /* fprintf(stderr, "ignore: %s", line); */
 334                         continue;
 335                 }
 336                 if (escaped) {
 337                         escaped--;
 338                         /* fprintf(stderr, "escaped: %s", line); */
 339                         continue;
 340                 }
 341                 *p = '\0';
 342                 strlcat(encoded, line, sizeof(encoded));
 343         }
 344         len = strlen(encoded);
 345         if (((len % 4) == 3) &&
 346             (encoded[len-1] == '=') &&
 347             (encoded[len-2] == '=') &&
 348             (encoded[len-3] == '='))
 349                 encoded[len-3] = '\0';
 350         blen = uudecode(encoded, blob, sizeof(blob));
 351         if (blen < 0) {
 352                 fprintf(stderr, "uudecode failed.\n");
 353                 exit(1);
 354         }
 355         k = private ?
 356             do_convert_private_ssh2_from_blob(blob, blen) :
 357             key_from_blob(blob, blen);
 358         if (k == NULL) {
 359                 fprintf(stderr, "decode blob failed.\n");
 360                 exit(1);
 361         }
 362         ok = private ?
 363             (k->type == KEY_DSA ?
 364                  PEM_write_DSAPrivateKey(stdout, k->dsa, NULL, NULL, 0, NULL, NULL) :
 365                  PEM_write_RSAPrivateKey(stdout, k->rsa, NULL, NULL, 0, NULL, NULL)) :
 366             key_write(k, stdout);
 367         if (!ok) {
 368                 fprintf(stderr, "key write failed");
 369                 exit(1);
 370         }
 371         key_free(k);
 372         if (!private)
 373                 fprintf(stdout, "\n");
 374         fclose(fp);
 375         exit(0);
 376 }
 377
 378 static void
 379 do_print_public(struct passwd *pw)
 380 {
 381         Key *prv;
 382         struct stat st;
 383
 384         if (!have_identity)
 385                 ask_filename(pw, "Enter file in which the key is");
 386         if (stat(identity_file, &st) < 0) {
 387                 perror(identity_file);
 388                 exit(1);
 389         }
 390         prv = load_identity(identity_file);
 391         if (prv == NULL) {
 392                 fprintf(stderr, "load failed\n");
 393                 exit(1);
 394         }
 395         if (!key_write(prv, stdout))
 396                 fprintf(stderr, "key_write failed");
 397         key_free(prv);
 398         fprintf(stdout, "\n");
 399         exit(0);
 400 }
 401
 402 #ifdef SMARTCARD
 403 static void
 404 do_upload(struct passwd *pw, const char *sc_reader_id)
 405 {
 406         Key *prv = NULL;
 407         struct stat st;
 408         int ret;
 409
 410         if (!have_identity)
 411                 ask_filename(pw, "Enter file in which the key is");
 412         if (stat(identity_file, &st) < 0) {
 413                 perror(identity_file);
 414                 exit(1);
 415         }
 416         prv = load_identity(identity_file);
 417         if (prv == NULL) {
 418                 error("load failed");
 419                 exit(1);
 420         }
 421         ret = sc_put_key(prv, sc_reader_id);
 422         key_free(prv);
 423         if (ret < 0)
 424                 exit(1);
 425         logit("loading key done");
 426         exit(0);
 427 }
 428
 429 static void
 430 do_download(struct passwd *pw, const char *sc_reader_id)
 431 {
 432         Key **keys = NULL;
 433         int i;
 434
 435         keys = sc_get_keys(sc_reader_id, NULL);
 436         if (keys == NULL)
 437                 fatal("cannot read public key from smartcard");
 438         for (i = 0; keys[i]; i++) {
 439                 key_write(keys[i], stdout);
 440                 key_free(keys[i]);
 441                 fprintf(stdout, "\n");
 442         }
 443         xfree(keys);
 444         exit(0);
 445 }
 446 #endif /* SMARTCARD */
 447
 448 static void
 449 do_fingerprint(struct passwd *pw)
 450 {
 451         FILE *f;
 452         Key *public;
 453         char *comment = NULL, *cp, *ep, line[16*1024], *fp;
 454         int i, skip = 0, num = 1, invalid = 1;
 455         enum fp_rep rep;
 456         enum fp_type fptype;
 457         struct stat st;
 458
 459         fptype = print_bubblebabble ? SSH_FP_SHA1 : SSH_FP_MD5;
 460         rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_HEX;
 461
 462         if (!have_identity)
 463                 ask_filename(pw, "Enter file in which the key is");
 464         if (stat(identity_file, &st) < 0) {
 465                 perror(identity_file);
 466                 exit(1);
 467         }
 468         public = key_load_public(identity_file, &comment);
 469         if (public != NULL) {
 470                 fp = key_fingerprint(public, fptype, rep);
 471                 printf("%u %s %s\n", key_size(public), fp, comment);
 472                 key_free(public);
 473                 xfree(comment);
 474                 xfree(fp);
 475                 exit(0);
 476         }
 477         if (comment)
 478                 xfree(comment);
 479
 480         f = fopen(identity_file, "r");
 481         if (f != NULL) {
 482                 while (fgets(line, sizeof(line), f)) {
 483                         i = strlen(line) - 1;
 484                         if (line[i] != '\n') {
 485                                 error("line %d too long: %.40s...", num, line);
 486                                 skip = 1;
 487                                 continue;
 488                         }
 489                         num++;
 490                         if (skip) {
 491                                 skip = 0;
 492                                 continue;
 493                         }
 494                         line[i] = '\0';
 495
 496                         /* Skip leading whitespace, empty and comment lines. */
 497                         for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
 498                                 ;
 499                         if (!*cp || *cp == '\n' || *cp == '#')
 500                                 continue ;
 501                         i = strtol(cp, &ep, 10);
 502                         if (i == 0 || ep == NULL || (*ep != ' ' && *ep != '\t')) {
 503                                 int quoted = 0;
 504                                 comment = cp;
 505                                 for (; *cp && (quoted || (*cp != ' ' &&
 506                                     *cp != '\t')); cp++) {
 507                                         if (*cp == '\\' && cp[1] == '"')
 508                                                 cp++;   /* Skip both */
 509                                         else if (*cp == '"')
 510                                                 quoted = !quoted;
 511                                 }
 512                                 if (!*cp)
 513                                         continue;
 514                                 *cp++ = '\0';
 515                         }
 516                         ep = cp;
 517                         public = key_new(KEY_RSA1);
 518                         if (key_read(public, &cp) != 1) {
 519                                 cp = ep;
 520                                 key_free(public);
 521                                 public = key_new(KEY_UNSPEC);
 522                                 if (key_read(public, &cp) != 1) {
 523                                         key_free(public);
 524                                         continue;
 525                                 }
 526                         }
 527                         comment = *cp ? cp : comment;
 528                         fp = key_fingerprint(public, fptype, rep);
 529                         printf("%u %s %s\n", key_size(public), fp,
 530                             comment ? comment : "no comment");
 531                         xfree(fp);
 532                         key_free(public);
 533                         invalid = 0;
 534                 }
 535                 fclose(f);
 536         }
 537         if (invalid) {
 538                 printf("%s is not a public key file.\n", identity_file);
 539                 exit(1);
 540         }
 541         exit(0);
 542 }
 543
 544 /*
 545  * Perform changing a passphrase.  The argument is the passwd structure
 546  * for the current user.
 547  */
 548 static void
 549 do_change_passphrase(struct passwd *pw)
 550 {
 551         char *comment;
 552         char *old_passphrase, *passphrase1, *passphrase2;
 553         struct stat st;
 554         Key *private;
 555
 556         if (!have_identity)
 557                 ask_filename(pw, "Enter file in which the key is");
 558         if (stat(identity_file, &st) < 0) {
 559                 perror(identity_file);
 560                 exit(1);
 561         }
 562         /* Try to load the file with empty passphrase. */
 563         private = key_load_private(identity_file, "", &comment);
 564         if (private == NULL) {
 565                 if (identity_passphrase)
 566                         old_passphrase = xstrdup(identity_passphrase);
 567                 else
 568                         old_passphrase =
 569                             read_passphrase("Enter old passphrase: ",
 570                             RP_ALLOW_STDIN);
 571                 private = key_load_private(identity_file, old_passphrase,
 572                     &comment);
 573                 memset(old_passphrase, 0, strlen(old_passphrase));
 574                 xfree(old_passphrase);
 575                 if (private == NULL) {
 576                         printf("Bad passphrase.\n");
 577                         exit(1);
 578                 }
 579         }
 580         printf("Key has comment '%s'\n", comment);
 581
 582         /* Ask the new passphrase (twice). */
 583         if (identity_new_passphrase) {
 584                 passphrase1 = xstrdup(identity_new_passphrase);
 585                 passphrase2 = NULL;
 586         } else {
 587                 passphrase1 =
 588                         read_passphrase("Enter new passphrase (empty for no "
 589                             "passphrase): ", RP_ALLOW_STDIN);
 590                 passphrase2 = read_passphrase("Enter same passphrase again: ",
 591                     RP_ALLOW_STDIN);
 592
 593                 /* Verify that they are the same. */
 594                 if (strcmp(passphrase1, passphrase2) != 0) {
 595                         memset(passphrase1, 0, strlen(passphrase1));
 596                         memset(passphrase2, 0, strlen(passphrase2));
 597                         xfree(passphrase1);
 598                         xfree(passphrase2);
 599                         printf("Pass phrases do not match.  Try again.\n");
 600                         exit(1);
 601                 }
 602                 /* Destroy the other copy. */
 603                 memset(passphrase2, 0, strlen(passphrase2));
 604                 xfree(passphrase2);
 605         }
 606
 607         /* Save the file using the new passphrase. */
 608         if (!key_save_private(private, identity_file, passphrase1, comment)) {
 609                 printf("Saving the key failed: %s.\n", identity_file);
 610                 memset(passphrase1, 0, strlen(passphrase1));
 611                 xfree(passphrase1);
 612                 key_free(private);
 613                 xfree(comment);
 614                 exit(1);
 615         }
 616         /* Destroy the passphrase and the copy of the key in memory. */
 617         memset(passphrase1, 0, strlen(passphrase1));
 618         xfree(passphrase1);
 619         key_free(private);               /* Destroys contents */
 620         xfree(comment);
 621
 622         printf("Your identification has been saved with the new passphrase.\n");
 623         exit(0);
 624 }
 625
 626 /*
 627  * Print the SSHFP RR.
 628  */
 629 static void
 630 do_print_resource_record(struct passwd *pw, char *hostname)
 631 {
 632         Key *public;
 633         char *comment = NULL;
 634         struct stat st;
 635
 636         if (!have_identity)
 637                 ask_filename(pw, "Enter file in which the key is");
 638         if (stat(identity_file, &st) < 0) {
 639                 perror(identity_file);
 640                 exit(1);
 641         }
 642         public = key_load_public(identity_file, &comment);
 643         if (public != NULL) {
 644                 export_dns_rr(hostname, public, stdout, print_generic);
 645                 key_free(public);
 646                 xfree(comment);
 647                 exit(0);
 648         }
 649         if (comment)
 650                 xfree(comment);
 651
 652         printf("failed to read v2 public key from %s.\n", identity_file);
 653         exit(1);
 654 }
 655
 656 /*
 657  * Change the comment of a private key file.
 658  */
 659 static void
 660 do_change_comment(struct passwd *pw)
 661 {
 662         char new_comment[1024], *comment, *passphrase;
 663         Key *private;
 664         Key *public;
 665         struct stat st;
 666         FILE *f;
 667         int fd;
 668
 669         if (!have_identity)
 670                 ask_filename(pw, "Enter file in which the key is");
 671         if (stat(identity_file, &st) < 0) {
 672                 perror(identity_file);
 673                 exit(1);
 674         }
 675         private = key_load_private(identity_file, "", &comment);
 676         if (private == NULL) {
 677                 if (identity_passphrase)
 678                         passphrase = xstrdup(identity_passphrase);
 679                 else if (identity_new_passphrase)
 680                         passphrase = xstrdup(identity_new_passphrase);
 681                 else
 682                         passphrase = read_passphrase("Enter passphrase: ",
 683                             RP_ALLOW_STDIN);
 684                 /* Try to load using the passphrase. */
 685                 private = key_load_private(identity_file, passphrase, &comment);
 686                 if (private == NULL) {
 687                         memset(passphrase, 0, strlen(passphrase));
 688                         xfree(passphrase);
 689                         printf("Bad passphrase.\n");
 690                         exit(1);
 691                 }
 692         } else {
 693                 passphrase = xstrdup("");
 694         }
 695         if (private->type != KEY_RSA1) {
 696                 fprintf(stderr, "Comments are only supported for RSA1 keys.\n");
 697                 key_free(private);
 698                 exit(1);
 699         }
 700         printf("Key now has comment '%s'\n", comment);
 701
 702         if (identity_comment) {
 703                 strlcpy(new_comment, identity_comment, sizeof(new_comment));
 704         } else {
 705                 printf("Enter new comment: ");
 706                 fflush(stdout);
 707                 if (!fgets(new_comment, sizeof(new_comment), stdin)) {
 708                         memset(passphrase, 0, strlen(passphrase));
 709                         key_free(private);
 710                         exit(1);
 711                 }
 712                 if (strchr(new_comment, '\n'))
 713                         *strchr(new_comment, '\n') = 0;
 714         }
 715
 716         /* Save the file using the new passphrase. */
 717         if (!key_save_private(private, identity_file, passphrase, new_comment)) {
 718                 printf("Saving the key failed: %s.\n", identity_file);
 719                 memset(passphrase, 0, strlen(passphrase));
 720                 xfree(passphrase);
 721                 key_free(private);
 722                 xfree(comment);
 723                 exit(1);
 724         }
 725         memset(passphrase, 0, strlen(passphrase));
 726         xfree(passphrase);
 727         public = key_from_private(private);
 728         key_free(private);
 729
 730         strlcat(identity_file, ".pub", sizeof(identity_file));
 731         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 732         if (fd == -1) {
 733                 printf("Could not save your public key in %s\n", identity_file);
 734                 exit(1);
 735         }
 736         f = fdopen(fd, "w");
 737         if (f == NULL) {
 738                 printf("fdopen %s failed", identity_file);
 739                 exit(1);
 740         }
 741         if (!key_write(public, f))
 742                 fprintf(stderr, "write key failed");
 743         key_free(public);
 744         fprintf(f, " %s\n", new_comment);
 745         fclose(f);
 746
 747         xfree(comment);
 748
 749         printf("The comment in your key file has been changed.\n");
 750         exit(0);
 751 }
 752
 753 static void
 754 usage(void)
 755 {
 756         fprintf(stderr, "Usage: %s [options]\n", __progname);
 757         fprintf(stderr, "Options:\n");
 758         fprintf(stderr, "  -b bits     Number of bits in the key to create.\n");
 759         fprintf(stderr, "  -c          Change comment in private and public key files.\n");
 760         fprintf(stderr, "  -e          Convert OpenSSH to IETF SECSH key file.\n");
 761         fprintf(stderr, "  -f filename Filename of the key file.\n");
 762         fprintf(stderr, "  -g          Use generic DNS resource record format.\n");
 763         fprintf(stderr, "  -i          Convert IETF SECSH to OpenSSH key file.\n");
 764         fprintf(stderr, "  -l          Show fingerprint of key file.\n");
 765         fprintf(stderr, "  -p          Change passphrase of private key file.\n");
 766         fprintf(stderr, "  -q          Quiet.\n");
 767         fprintf(stderr, "  -y          Read private key file and print public key.\n");
 768         fprintf(stderr, "  -t type     Specify type of key to create.\n");
 769         fprintf(stderr, "  -B          Show bubblebabble digest of key file.\n");
 770         fprintf(stderr, "  -C comment  Provide new comment.\n");
 771         fprintf(stderr, "  -N phrase   Provide new passphrase.\n");
 772         fprintf(stderr, "  -P phrase   Provide old passphrase.\n");
 773         fprintf(stderr, "  -r hostname Print DNS resource record.\n");
 774 #ifdef SMARTCARD
 775         fprintf(stderr, "  -D reader   Download public key from smartcard.\n");
 776         fprintf(stderr, "  -U reader   Upload private key to smartcard.\n");
 777 #endif /* SMARTCARD */
 778
 779         fprintf(stderr, "  -G file     Generate candidates for DH-GEX moduli\n");
 780         fprintf(stderr, "  -T file     Screen candidates for DH-GEX moduli\n");
 781
 782         exit(1);
 783 }
 784
 785 /*
 786  * Main program for key management.
 787  */
 788 int
 789 main(int ac, char **av)
 790 {
 791         char dotsshdir[MAXPATHLEN], comment[1024], *passphrase1, *passphrase2;
 792         char out_file[MAXPATHLEN], *reader_id = NULL;
 793         char *resource_record_hostname = NULL;
 794         Key *private, *public;
 795         struct passwd *pw;
 796         struct stat st;
 797         int opt, type, fd, download = 0, memory = 0;
 798         int generator_wanted = 0, trials = 100;
 799         int do_gen_candidates = 0, do_screen_candidates = 0;
 800         int log_level = SYSLOG_LEVEL_INFO;
 801         BIGNUM *start = NULL;
 802         FILE *f;
 803
 804         extern int optind;
 805         extern char *optarg;
 806
 807         __progname = ssh_get_progname(av[0]);
 808
 809         SSLeay_add_all_algorithms();
 810         log_init(av[0], SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_USER, 1);
 811
 812         init_rng();
 813         seed_rng();
 814
 815         /* we need this for the home * directory.  */
 816         pw = getpwuid(getuid());
 817         if (!pw) {
 818                 printf("You don't exist, go away!\n");
 819                 exit(1);
 820         }
 821         if (gethostname(hostname, sizeof(hostname)) < 0) {
 822                 perror("gethostname");
 823                 exit(1);
 824         }
 825
 826         while ((opt = getopt(ac, av,
 827             "degiqpclBRvxXyb:f:t:U:D:P:N:C:r:g:T:G:M:S:a:W:")) != -1) {
 828                 switch (opt) {
 829                 case 'b':
 830                         bits = atoi(optarg);
 831                         if (bits < 512 || bits > 32768) {
 832                                 printf("Bits has bad value.\n");
 833                                 exit(1);
 834                         }
 835                         break;
 836                 case 'l':
 837                         print_fingerprint = 1;
 838                         break;
 839                 case 'B':
 840                         print_bubblebabble = 1;
 841                         break;
 842                 case 'p':
 843                         change_passphrase = 1;
 844                         break;
 845                 case 'c':
 846                         change_comment = 1;
 847                         break;
 848                 case 'f':
 849                         strlcpy(identity_file, optarg, sizeof(identity_file));
 850                         have_identity = 1;
 851                         break;
 852                 case 'g':
 853                         print_generic = 1;
 854                         break;
 855                 case 'P':
 856                         identity_passphrase = optarg;
 857                         break;
 858                 case 'N':
 859                         identity_new_passphrase = optarg;
 860                         break;
 861                 case 'C':
 862                         identity_comment = optarg;
 863                         break;
 864                 case 'q':
 865                         quiet = 1;
 866                         break;
 867                 case 'R':
 868                         /* unused */
 869                         exit(0);
 870                         break;
 871                 case 'e':
 872                 case 'x':
 873                         /* export key */
 874                         convert_to_ssh2 = 1;
 875                         break;
 876                 case 'i':
 877                 case 'X':
 878                         /* import key */
 879                         convert_from_ssh2 = 1;
 880                         break;
 881                 case 'y':
 882                         print_public = 1;
 883                         break;
 884                 case 'd':
 885                         key_type_name = "dsa";
 886                         break;
 887                 case 't':
 888                         key_type_name = optarg;
 889                         break;
 890                 case 'D':
 891                         download = 1;
 892                 case 'U':
 893                         reader_id = optarg;
 894                         break;
 895                 case 'v':
 896                         if (log_level == SYSLOG_LEVEL_INFO)
 897                                 log_level = SYSLOG_LEVEL_DEBUG1;
 898                         else {
 899                                 if (log_level >= SYSLOG_LEVEL_DEBUG1 &&
 900                                     log_level < SYSLOG_LEVEL_DEBUG3)
 901                                         log_level++;
 902                         }
 903                         break;
 904                 case 'r':
 905                         resource_record_hostname = optarg;
 906                         break;
 907                 case 'W':
 908                         generator_wanted = atoi(optarg);
 909                         if (generator_wanted < 1)
 910                                 fatal("Desired generator has bad value.");
 911                         break;
 912                 case 'a':
 913                         trials = atoi(optarg);
 914                         if (trials < TRIAL_MINIMUM) {
 915                                 fatal("Minimum primality trials is %d",
 916                                     TRIAL_MINIMUM);
 917                         }
 918                         break;
 919                 case 'M':
 920                         memory = atoi(optarg);
 921                         if (memory != 0 &&
 922                            (memory < LARGE_MINIMUM || memory > LARGE_MAXIMUM)) {
 923                                 fatal("Invalid memory amount (min %ld, max %ld)",
 924                                     LARGE_MINIMUM, LARGE_MAXIMUM);
 925                         }
 926                         break;
 927                 case 'G':
 928                         do_gen_candidates = 1;
 929                         strlcpy(out_file, optarg, sizeof(out_file));
 930                         break;
 931                 case 'T':
 932                         do_screen_candidates = 1;
 933                         strlcpy(out_file, optarg, sizeof(out_file));
 934                         break;
 935                 case 'S':
 936                         /* XXX - also compare length against bits */
 937                         if (BN_hex2bn(&start, optarg) == 0)
 938                                 fatal("Invalid start point.");
 939                         break;
 940                 case '?':
 941                 default:
 942                         usage();
 943                 }
 944         }
 945
 946         /* reinit */
 947         log_init(av[0], log_level, SYSLOG_FACILITY_USER, 1);
 948
 949         if (optind < ac) {
 950                 printf("Too many arguments.\n");
 951                 usage();
 952         }
 953         if (change_passphrase && change_comment) {
 954                 printf("Can only have one of -p and -c.\n");
 955                 usage();
 956         }
 957         if (print_fingerprint || print_bubblebabble)
 958                 do_fingerprint(pw);
 959         if (change_passphrase)
 960                 do_change_passphrase(pw);
 961         if (change_comment)
 962                 do_change_comment(pw);
 963         if (convert_to_ssh2)
 964                 do_convert_to_ssh2(pw);
 965         if (convert_from_ssh2)
 966                 do_convert_from_ssh2(pw);
 967         if (print_public)
 968                 do_print_public(pw);
 969         if (resource_record_hostname != NULL) {
 970                 do_print_resource_record(pw, resource_record_hostname);
 971         }
 972         if (reader_id != NULL) {
 973 #ifdef SMARTCARD
 974                 if (download)
 975                         do_download(pw, reader_id);
 976                 else
 977                         do_upload(pw, reader_id);
 978 #else /* SMARTCARD */
 979                 fatal("no support for smartcards.");
 980 #endif /* SMARTCARD */
 981         }
 982
 983         if (do_gen_candidates) {
 984                 FILE *out = fopen(out_file, "w");
 985
 986                 if (out == NULL) {
 987                         error("Couldn't open modulus candidate file \"%s\": %s",
 988                             out_file, strerror(errno));
 989                         return (1);
 990                 }
 991                 if (gen_candidates(out, memory, bits, start) != 0)
 992                         fatal("modulus candidate generation failed\n");
 993
 994                 return (0);
 995         }
 996
 997         if (do_screen_candidates) {
 998                 FILE *in;
 999                 FILE *out = fopen(out_file, "w");
1000
1001                 if (have_identity && strcmp(identity_file, "-") != 0) {
1002                         if ((in = fopen(identity_file, "r")) == NULL) {
1003                                 fatal("Couldn't open modulus candidate "
1004                                     "file \"%s\": %s", identity_file,
1005                                     strerror(errno));
1006                         }
1007                 } else
1008                         in = stdin;
1009
1010                 if (out == NULL) {
1011                         fatal("Couldn't open moduli file \"%s\": %s",
1012                             out_file, strerror(errno));
1013                 }
1014                 if (prime_test(in, out, trials, generator_wanted) != 0)
1015                         fatal("modulus screening failed\n");
1016                 return (0);
1017         }
1018
1019         arc4random_stir();
1020
1021         if (key_type_name == NULL) {
1022                 printf("You must specify a key type (-t).\n");
1023                 usage();
1024         }
1025         type = key_type_from_name(key_type_name);
1026         if (type == KEY_UNSPEC) {
1027                 fprintf(stderr, "unknown key type %s\n", key_type_name);
1028                 exit(1);
1029         }
1030         if (!quiet)
1031                 printf("Generating public/private %s key pair.\n", key_type_name);
1032         private = key_generate(type, bits);
1033         if (private == NULL) {
1034                 fprintf(stderr, "key_generate failed");
1035                 exit(1);
1036         }
1037         public  = key_from_private(private);
1038
1039         if (!have_identity)
1040                 ask_filename(pw, "Enter file in which to save the key");
1041
1042         /* Create ~/.ssh directory if it doesn\'t already exist. */
1043         snprintf(dotsshdir, sizeof dotsshdir, "%s/%s", pw->pw_dir, _PATH_SSH_USER_DIR);
1044         if (strstr(identity_file, dotsshdir) != NULL &&
1045             stat(dotsshdir, &st) < 0) {
1046                 if (mkdir(dotsshdir, 0700) < 0)
1047                         error("Could not create directory '%s'.", dotsshdir);
1048                 else if (!quiet)
1049                         printf("Created directory '%s'.\n", dotsshdir);
1050         }
1051         /* If the file already exists, ask the user to confirm. */
1052         if (stat(identity_file, &st) >= 0) {
1053                 char yesno[3];
1054                 printf("%s already exists.\n", identity_file);
1055                 printf("Overwrite (y/n)? ");
1056                 fflush(stdout);
1057                 if (fgets(yesno, sizeof(yesno), stdin) == NULL)
1058                         exit(1);
1059                 if (yesno[0] != 'y' && yesno[0] != 'Y')
1060                         exit(1);
1061         }
1062         /* Ask for a passphrase (twice). */
1063         if (identity_passphrase)
1064                 passphrase1 = xstrdup(identity_passphrase);
1065         else if (identity_new_passphrase)
1066                 passphrase1 = xstrdup(identity_new_passphrase);
1067         else {
1068 passphrase_again:
1069                 passphrase1 =
1070                         read_passphrase("Enter passphrase (empty for no "
1071                             "passphrase): ", RP_ALLOW_STDIN);
1072                 passphrase2 = read_passphrase("Enter same passphrase again: ",
1073                     RP_ALLOW_STDIN);
1074                 if (strcmp(passphrase1, passphrase2) != 0) {
1075                         /*
1076                          * The passphrases do not match.  Clear them and
1077                          * retry.
1078                          */
1079                         memset(passphrase1, 0, strlen(passphrase1));
1080                         memset(passphrase2, 0, strlen(passphrase2));
1081                         xfree(passphrase1);
1082                         xfree(passphrase2);
1083                         printf("Passphrases do not match.  Try again.\n");
1084                         goto passphrase_again;
1085                 }
1086                 /* Clear the other copy of the passphrase. */
1087                 memset(passphrase2, 0, strlen(passphrase2));
1088                 xfree(passphrase2);
1089         }
1090
1091         if (identity_comment) {
1092                 strlcpy(comment, identity_comment, sizeof(comment));
1093         } else {
1094                 /* Create default commend field for the passphrase. */
1095                 snprintf(comment, sizeof comment, "%s@%s", pw->pw_name, hostname);
1096         }
1097
1098         /* Save the key with the given passphrase and comment. */
1099         if (!key_save_private(private, identity_file, passphrase1, comment)) {
1100                 printf("Saving the key failed: %s.\n", identity_file);
1101                 memset(passphrase1, 0, strlen(passphrase1));
1102                 xfree(passphrase1);
1103                 exit(1);
1104         }
1105         /* Clear the passphrase. */
1106         memset(passphrase1, 0, strlen(passphrase1));
1107         xfree(passphrase1);
1108
1109         /* Clear the private key and the random number generator. */
1110         key_free(private);
1111         arc4random_stir();
1112
1113         if (!quiet)
1114                 printf("Your identification has been saved in %s.\n", identity_file);
1115
1116         strlcat(identity_file, ".pub", sizeof(identity_file));
1117         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
1118         if (fd == -1) {
1119                 printf("Could not save your public key in %s\n", identity_file);
1120                 exit(1);
1121         }
1122         f = fdopen(fd, "w");
1123         if (f == NULL) {
1124                 printf("fdopen %s failed", identity_file);
1125                 exit(1);
1126         }
1127         if (!key_write(public, f))
1128                 fprintf(stderr, "write key failed");
1129         fprintf(f, " %s\n", comment);
1130         fclose(f);
1131
1132         if (!quiet) {
1133                 char *fp = key_fingerprint(public, SSH_FP_MD5, SSH_FP_HEX);
1134                 printf("Your public key has been saved in %s.\n",
1135                     identity_file);
1136                 printf("The key fingerprint is:\n");
1137                 printf("%s %s\n", fp, comment);
1138                 xfree(fp);
1139         }
1140
1141         key_free(public);
1142         exit(0);
1143 }