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 1.89 2001/12/29 21:56:01 stevesk 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 #ifdef SMARTCARD
  32 #include <sectok.h>
  33 #include <openssl/engine.h>
  34 #include "scard.h"
  35 #endif
  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
  76 char *key_type_name = NULL;
  77
  78 /* argv0 */
  79 #ifdef HAVE___PROGNAME
  80 extern char *__progname;
  81 #else
  82 char *__progname;
  83 #endif
  84
  85 char hostname[MAXHOSTNAMELEN];
  86
  87 static void
  88 ask_filename(struct passwd *pw, const char *prompt)
  89 {
  90         char buf[1024];
  91         char *name = NULL;
  92
  93         switch (key_type_from_name(key_type_name)) {
  94         case KEY_RSA1:
  95                 name = _PATH_SSH_CLIENT_IDENTITY;
  96                 break;
  97         case KEY_DSA:
  98                 name = _PATH_SSH_CLIENT_ID_DSA;
  99                 break;
 100         case KEY_RSA:
 101                 name = _PATH_SSH_CLIENT_ID_RSA;
 102                 break;
 103         default:
 104                 fprintf(stderr, "bad key type");
 105                 exit(1);
 106                 break;
 107         }
 108         snprintf(identity_file, sizeof(identity_file), "%s/%s", pw->pw_dir, name);
 109         fprintf(stderr, "%s (%s): ", prompt, identity_file);
 110         fflush(stderr);
 111         if (fgets(buf, sizeof(buf), stdin) == NULL)
 112                 exit(1);
 113         if (strchr(buf, '\n'))
 114                 *strchr(buf, '\n') = 0;
 115         if (strcmp(buf, "") != 0)
 116                 strlcpy(identity_file, buf, sizeof(identity_file));
 117         have_identity = 1;
 118 }
 119
 120 static Key *
 121 load_identity(char *filename)
 122 {
 123         char *pass;
 124         Key *prv;
 125
 126         prv = key_load_private(filename, "", NULL);
 127         if (prv == NULL) {
 128                 if (identity_passphrase)
 129                         pass = xstrdup(identity_passphrase);
 130                 else
 131                         pass = read_passphrase("Enter passphrase: ",
 132                             RP_ALLOW_STDIN);
 133                 prv = key_load_private(filename, pass, NULL);
 134                 memset(pass, 0, strlen(pass));
 135                 xfree(pass);
 136         }
 137         return prv;
 138 }
 139
 140 #define SSH_COM_PUBLIC_BEGIN            "---- BEGIN SSH2 PUBLIC KEY ----"
 141 #define SSH_COM_PUBLIC_END              "---- END SSH2 PUBLIC KEY ----"
 142 #define SSH_COM_PRIVATE_BEGIN           "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----"
 143 #define SSH_COM_PRIVATE_KEY_MAGIC       0x3f6ff9eb
 144
 145 static void
 146 do_convert_to_ssh2(struct passwd *pw)
 147 {
 148         Key *k;
 149         int len;
 150         u_char *blob;
 151         struct stat st;
 152
 153         if (!have_identity)
 154                 ask_filename(pw, "Enter file in which the key is");
 155         if (stat(identity_file, &st) < 0) {
 156                 perror(identity_file);
 157                 exit(1);
 158         }
 159         if ((k = key_load_public(identity_file, NULL)) == NULL) {
 160                 if ((k = load_identity(identity_file)) == NULL) {
 161                         fprintf(stderr, "load failed\n");
 162                         exit(1);
 163                 }
 164         }
 165         if (key_to_blob(k, &blob, &len) <= 0) {
 166                 fprintf(stderr, "key_to_blob failed\n");
 167                 exit(1);
 168         }
 169         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_BEGIN);
 170         fprintf(stdout,
 171             "Comment: \"%d-bit %s, converted from OpenSSH by %s@%s\"\n",
 172             key_size(k), key_type(k),
 173             pw->pw_name, hostname);
 174         dump_base64(stdout, blob, len);
 175         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_END);
 176         key_free(k);
 177         xfree(blob);
 178         exit(0);
 179 }
 180
 181 static void
 182 buffer_get_bignum_bits(Buffer *b, BIGNUM *value)
 183 {
 184         int bits = buffer_get_int(b);
 185         int bytes = (bits + 7) / 8;
 186
 187         if (buffer_len(b) < bytes)
 188                 fatal("buffer_get_bignum_bits: input buffer too small: "
 189                     "need %d have %d", bytes, buffer_len(b));
 190         BN_bin2bn(buffer_ptr(b), bytes, value);
 191         buffer_consume(b, bytes);
 192 }
 193
 194 static Key *
 195 do_convert_private_ssh2_from_blob(u_char *blob, int blen)
 196 {
 197         Buffer b;
 198         Key *key = NULL;
 199         char *type, *cipher;
 200         u_char *sig, data[] = "abcde12345";
 201         int magic, rlen, ktype, i1, i2, i3, i4;
 202         u_int slen;
 203         u_long e;
 204
 205         buffer_init(&b);
 206         buffer_append(&b, blob, blen);
 207
 208         magic  = buffer_get_int(&b);
 209         if (magic != SSH_COM_PRIVATE_KEY_MAGIC) {
 210                 error("bad magic 0x%x != 0x%x", magic, SSH_COM_PRIVATE_KEY_MAGIC);
 211                 buffer_free(&b);
 212                 return NULL;
 213         }
 214         i1 = buffer_get_int(&b);
 215         type   = buffer_get_string(&b, NULL);
 216         cipher = buffer_get_string(&b, NULL);
 217         i2 = buffer_get_int(&b);
 218         i3 = buffer_get_int(&b);
 219         i4 = buffer_get_int(&b);
 220         debug("ignore (%d %d %d %d)", i1,i2,i3,i4);
 221         if (strcmp(cipher, "none") != 0) {
 222                 error("unsupported cipher %s", cipher);
 223                 xfree(cipher);
 224                 buffer_free(&b);
 225                 xfree(type);
 226                 return NULL;
 227         }
 228         xfree(cipher);
 229
 230         if (strstr(type, "dsa")) {
 231                 ktype = KEY_DSA;
 232         } else if (strstr(type, "rsa")) {
 233                 ktype = KEY_RSA;
 234         } else {
 235                 xfree(type);
 236                 return NULL;
 237         }
 238         key = key_new_private(ktype);
 239         xfree(type);
 240
 241         switch (key->type) {
 242         case KEY_DSA:
 243                 buffer_get_bignum_bits(&b, key->dsa->p);
 244                 buffer_get_bignum_bits(&b, key->dsa->g);
 245                 buffer_get_bignum_bits(&b, key->dsa->q);
 246                 buffer_get_bignum_bits(&b, key->dsa->pub_key);
 247                 buffer_get_bignum_bits(&b, key->dsa->priv_key);
 248                 break;
 249         case KEY_RSA:
 250                 e  = buffer_get_char(&b);
 251                 debug("e %lx", e);
 252                 if (e < 30) {
 253                         e <<= 8;
 254                         e += buffer_get_char(&b);
 255                         debug("e %lx", e);
 256                         e <<= 8;
 257                         e += buffer_get_char(&b);
 258                         debug("e %lx", e);
 259                 }
 260                 if (!BN_set_word(key->rsa->e, e)) {
 261                         buffer_free(&b);
 262                         key_free(key);
 263                         return NULL;
 264                 }
 265                 buffer_get_bignum_bits(&b, key->rsa->d);
 266                 buffer_get_bignum_bits(&b, key->rsa->n);
 267                 buffer_get_bignum_bits(&b, key->rsa->iqmp);
 268                 buffer_get_bignum_bits(&b, key->rsa->q);
 269                 buffer_get_bignum_bits(&b, key->rsa->p);
 270                 rsa_generate_additional_parameters(key->rsa);
 271                 break;
 272         }
 273         rlen = buffer_len(&b);
 274         if (rlen != 0)
 275                 error("do_convert_private_ssh2_from_blob: "
 276                     "remaining bytes in key blob %d", rlen);
 277         buffer_free(&b);
 278
 279         /* try the key */
 280         key_sign(key, &sig, &slen, data, sizeof(data));
 281         key_verify(key, sig, slen, data, sizeof(data));
 282         xfree(sig);
 283         return key;
 284 }
 285
 286 static void
 287 do_convert_from_ssh2(struct passwd *pw)
 288 {
 289         Key *k;
 290         int blen;
 291         char line[1024], *p;
 292         u_char blob[8096];
 293         char encoded[8096];
 294         struct stat st;
 295         int escaped = 0, private = 0, ok;
 296         FILE *fp;
 297
 298         if (!have_identity)
 299                 ask_filename(pw, "Enter file in which the key is");
 300         if (stat(identity_file, &st) < 0) {
 301                 perror(identity_file);
 302                 exit(1);
 303         }
 304         fp = fopen(identity_file, "r");
 305         if (fp == NULL) {
 306                 perror(identity_file);
 307                 exit(1);
 308         }
 309         encoded[0] = '\0';
 310         while (fgets(line, sizeof(line), fp)) {
 311                 if (!(p = strchr(line, '\n'))) {
 312                         fprintf(stderr, "input line too long.\n");
 313                         exit(1);
 314                 }
 315                 if (p > line && p[-1] == '\\')
 316                         escaped++;
 317                 if (strncmp(line, "----", 4) == 0 ||
 318                     strstr(line, ": ") != NULL) {
 319                         if (strstr(line, SSH_COM_PRIVATE_BEGIN) != NULL)
 320                                 private = 1;
 321                         if (strstr(line, " END ") != NULL) {
 322                                 break;
 323                         }
 324                         /* fprintf(stderr, "ignore: %s", line); */
 325                         continue;
 326                 }
 327                 if (escaped) {
 328                         escaped--;
 329                         /* fprintf(stderr, "escaped: %s", line); */
 330                         continue;
 331                 }
 332                 *p = '\0';
 333                 strlcat(encoded, line, sizeof(encoded));
 334         }
 335         blen = uudecode(encoded, (u_char *)blob, sizeof(blob));
 336         if (blen < 0) {
 337                 fprintf(stderr, "uudecode failed.\n");
 338                 exit(1);
 339         }
 340         k = private ?
 341             do_convert_private_ssh2_from_blob(blob, blen) :
 342             key_from_blob(blob, blen);
 343         if (k == NULL) {
 344                 fprintf(stderr, "decode blob failed.\n");
 345                 exit(1);
 346         }
 347         ok = private ?
 348             (k->type == KEY_DSA ?
 349                  PEM_write_DSAPrivateKey(stdout, k->dsa, NULL, NULL, 0, NULL, NULL) :
 350                  PEM_write_RSAPrivateKey(stdout, k->rsa, NULL, NULL, 0, NULL, NULL)) :
 351             key_write(k, stdout);
 352         if (!ok) {
 353                 fprintf(stderr, "key write failed");
 354                 exit(1);
 355         }
 356         key_free(k);
 357         fprintf(stdout, "\n");
 358         fclose(fp);
 359         exit(0);
 360 }
 361
 362 static void
 363 do_print_public(struct passwd *pw)
 364 {
 365         Key *prv;
 366         struct stat st;
 367
 368         if (!have_identity)
 369                 ask_filename(pw, "Enter file in which the key is");
 370         if (stat(identity_file, &st) < 0) {
 371                 perror(identity_file);
 372                 exit(1);
 373         }
 374         prv = load_identity(identity_file);
 375         if (prv == NULL) {
 376                 fprintf(stderr, "load failed\n");
 377                 exit(1);
 378         }
 379         if (!key_write(prv, stdout))
 380                 fprintf(stderr, "key_write failed");
 381         key_free(prv);
 382         fprintf(stdout, "\n");
 383         exit(0);
 384 }
 385
 386 #ifdef SMARTCARD
 387 #define NUM_RSA_KEY_ELEMENTS 5+1
 388 #define COPY_RSA_KEY(x, i) \
 389         do { \
 390                 len = BN_num_bytes(prv->rsa->x); \
 391                 elements[i] = xmalloc(len); \
 392                 debug("#bytes %d", len); \
 393                 if (BN_bn2bin(prv->rsa->x, elements[i]) < 0) \
 394                         goto done; \
 395         } while (0)
 396
 397 static int
 398 get_AUT0(char *aut0)
 399 {
 400         EVP_MD *evp_md = EVP_sha1();
 401         EVP_MD_CTX md;
 402         char *pass;
 403
 404         pass = read_passphrase("Enter passphrase for smartcard: ", RP_ALLOW_STDIN);
 405         if (pass == NULL)
 406                 return -1;
 407         EVP_DigestInit(&md, evp_md);
 408         EVP_DigestUpdate(&md, pass, strlen(pass));
 409         EVP_DigestFinal(&md, aut0, NULL);
 410         memset(pass, 0, strlen(pass));
 411         xfree(pass);
 412         return 0;
 413 }
 414
 415 static void
 416 do_upload(struct passwd *pw, const char *sc_reader_id)
 417 {
 418         Key *prv = NULL;
 419         struct stat st;
 420         u_char *elements[NUM_RSA_KEY_ELEMENTS];
 421         u_char key_fid[2];
 422         u_char DEFAUT0[] = {0xad, 0x9f, 0x61, 0xfe, 0xfa, 0x20, 0xce, 0x63};
 423         u_char AUT0[EVP_MAX_MD_SIZE];
 424         int len, status = 1, i, fd = -1, ret;
 425         int sw = 0, cla = 0x00;
 426
 427         for (i = 0; i < NUM_RSA_KEY_ELEMENTS; i++)
 428                 elements[i] = NULL;
 429         if (!have_identity)
 430                 ask_filename(pw, "Enter file in which the key is");
 431         if (stat(identity_file, &st) < 0) {
 432                 perror(identity_file);
 433                 goto done;
 434         }
 435         prv = load_identity(identity_file);
 436         if (prv == NULL) {
 437                 error("load failed");
 438                 goto done;
 439         }
 440         COPY_RSA_KEY(q, 0);
 441         COPY_RSA_KEY(p, 1);
 442         COPY_RSA_KEY(iqmp, 2);
 443         COPY_RSA_KEY(dmq1, 3);
 444         COPY_RSA_KEY(dmp1, 4);
 445         COPY_RSA_KEY(n, 5);
 446         len = BN_num_bytes(prv->rsa->n);
 447         fd = sectok_friendly_open(sc_reader_id, STONOWAIT, &sw);
 448         if (fd < 0) {
 449                 error("sectok_open failed: %s", sectok_get_sw(sw));
 450                 goto done;
 451         }
 452         if (! sectok_cardpresent(fd)) {
 453                 error("smartcard in reader %s not present",
 454                     sc_reader_id);
 455                 goto done;
 456         }
 457         ret = sectok_reset(fd, 0, NULL, &sw);
 458         if (ret <= 0) {
 459                 error("sectok_reset failed: %s", sectok_get_sw(sw));
 460                 goto done;
 461         }
 462         if ((cla = cyberflex_inq_class(fd)) < 0) {
 463                 error("cyberflex_inq_class failed");
 464                 goto done;
 465         }
 466         memcpy(AUT0, DEFAUT0, sizeof(DEFAUT0));
 467         if (cyberflex_verify_AUT0(fd, cla, AUT0, sizeof(DEFAUT0)) < 0) {
 468                 if (get_AUT0(AUT0) < 0 ||
 469                     cyberflex_verify_AUT0(fd, cla, AUT0, sizeof(DEFAUT0)) < 0) {
 470                         error("cyberflex_verify_AUT0 failed");
 471                         goto done;
 472                 }
 473         }
 474         key_fid[0] = 0x00;
 475         key_fid[1] = 0x12;
 476         if (cyberflex_load_rsa_priv(fd, cla, key_fid, 5, 8*len, elements,
 477             &sw) < 0) {
 478                 error("cyberflex_load_rsa_priv failed: %s", sectok_get_sw(sw));
 479                 goto done;
 480         }
 481         if (!sectok_swOK(sw))
 482                 goto done;
 483         log("cyberflex_load_rsa_priv done");
 484         key_fid[0] = 0x73;
 485         key_fid[1] = 0x68;
 486         if (cyberflex_load_rsa_pub(fd, cla, key_fid, len, elements[5],
 487             &sw) < 0) {
 488                 error("cyberflex_load_rsa_pub failed: %s", sectok_get_sw(sw));
 489                 goto done;
 490         }
 491         if (!sectok_swOK(sw))
 492                 goto done;
 493         log("cyberflex_load_rsa_pub done");
 494         status = 0;
 495         log("loading key done");
 496 done:
 497
 498         memset(elements[0], '\0', BN_num_bytes(prv->rsa->q));
 499         memset(elements[1], '\0', BN_num_bytes(prv->rsa->p));
 500         memset(elements[2], '\0', BN_num_bytes(prv->rsa->iqmp));
 501         memset(elements[3], '\0', BN_num_bytes(prv->rsa->dmq1));
 502         memset(elements[4], '\0', BN_num_bytes(prv->rsa->dmp1));
 503         memset(elements[5], '\0', BN_num_bytes(prv->rsa->n));
 504
 505         if (prv)
 506                 key_free(prv);
 507         for (i = 0; i < NUM_RSA_KEY_ELEMENTS; i++)
 508                 if (elements[i])
 509                         xfree(elements[i]);
 510         if (fd != -1)
 511                 sectok_close(fd);
 512         exit(status);
 513 }
 514
 515 static void
 516 do_download(struct passwd *pw, const char *sc_reader_id)
 517 {
 518         Key *pub = NULL;
 519
 520         pub = sc_get_key(sc_reader_id);
 521         if (pub == NULL)
 522                 fatal("cannot read public key from smartcard");
 523         key_write(pub, stdout);
 524         key_free(pub);
 525         fprintf(stdout, "\n");
 526         exit(0);
 527 }
 528 #endif /* SMARTCARD */
 529
 530 static void
 531 do_fingerprint(struct passwd *pw)
 532 {
 533         FILE *f;
 534         Key *public;
 535         char *comment = NULL, *cp, *ep, line[16*1024], *fp;
 536         int i, skip = 0, num = 1, invalid = 1;
 537         enum fp_rep rep;
 538         enum fp_type fptype;
 539         struct stat st;
 540
 541         fptype = print_bubblebabble ? SSH_FP_SHA1 : SSH_FP_MD5;
 542         rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_HEX;
 543
 544         if (!have_identity)
 545                 ask_filename(pw, "Enter file in which the key is");
 546         if (stat(identity_file, &st) < 0) {
 547                 perror(identity_file);
 548                 exit(1);
 549         }
 550         public = key_load_public(identity_file, &comment);
 551         if (public != NULL) {
 552                 fp = key_fingerprint(public, fptype, rep);
 553                 printf("%d %s %s\n", key_size(public), fp, comment);
 554                 key_free(public);
 555                 xfree(comment);
 556                 xfree(fp);
 557                 exit(0);
 558         }
 559         if (comment)
 560                 xfree(comment);
 561
 562         f = fopen(identity_file, "r");
 563         if (f != NULL) {
 564                 while (fgets(line, sizeof(line), f)) {
 565                         i = strlen(line) - 1;
 566                         if (line[i] != '\n') {
 567                                 error("line %d too long: %.40s...", num, line);
 568                                 skip = 1;
 569                                 continue;
 570                         }
 571                         num++;
 572                         if (skip) {
 573                                 skip = 0;
 574                                 continue;
 575                         }
 576                         line[i] = '\0';
 577
 578                         /* Skip leading whitespace, empty and comment lines. */
 579                         for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
 580                                 ;
 581                         if (!*cp || *cp == '\n' || *cp == '#')
 582                                 continue ;
 583                         i = strtol(cp, &ep, 10);
 584                         if (i == 0 || ep == NULL || (*ep != ' ' && *ep != '\t')) {
 585                                 int quoted = 0;
 586                                 comment = cp;
 587                                 for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
 588                                         if (*cp == '\\' && cp[1] == '"')
 589                                                 cp++;   /* Skip both */
 590                                         else if (*cp == '"')
 591                                                 quoted = !quoted;
 592                                 }
 593                                 if (!*cp)
 594                                         continue;
 595                                 *cp++ = '\0';
 596                         }
 597                         ep = cp;
 598                         public = key_new(KEY_RSA1);
 599                         if (key_read(public, &cp) != 1) {
 600                                 cp = ep;
 601                                 key_free(public);
 602                                 public = key_new(KEY_UNSPEC);
 603                                 if (key_read(public, &cp) != 1) {
 604                                         key_free(public);
 605                                         continue;
 606                                 }
 607                         }
 608                         comment = *cp ? cp : comment;
 609                         fp = key_fingerprint(public, fptype, rep);
 610                         printf("%d %s %s\n", key_size(public), fp,
 611                             comment ? comment : "no comment");
 612                         xfree(fp);
 613                         key_free(public);
 614                         invalid = 0;
 615                 }
 616                 fclose(f);
 617         }
 618         if (invalid) {
 619                 printf("%s is not a public key file.\n", identity_file);
 620                 exit(1);
 621         }
 622         exit(0);
 623 }
 624
 625 /*
 626  * Perform changing a passphrase.  The argument is the passwd structure
 627  * for the current user.
 628  */
 629 static void
 630 do_change_passphrase(struct passwd *pw)
 631 {
 632         char *comment;
 633         char *old_passphrase, *passphrase1, *passphrase2;
 634         struct stat st;
 635         Key *private;
 636
 637         if (!have_identity)
 638                 ask_filename(pw, "Enter file in which the key is");
 639         if (stat(identity_file, &st) < 0) {
 640                 perror(identity_file);
 641                 exit(1);
 642         }
 643         /* Try to load the file with empty passphrase. */
 644         private = key_load_private(identity_file, "", &comment);
 645         if (private == NULL) {
 646                 if (identity_passphrase)
 647                         old_passphrase = xstrdup(identity_passphrase);
 648                 else
 649                         old_passphrase =
 650                             read_passphrase("Enter old passphrase: ",
 651                             RP_ALLOW_STDIN);
 652                 private = key_load_private(identity_file, old_passphrase,
 653                     &comment);
 654                 memset(old_passphrase, 0, strlen(old_passphrase));
 655                 xfree(old_passphrase);
 656                 if (private == NULL) {
 657                         printf("Bad passphrase.\n");
 658                         exit(1);
 659                 }
 660         }
 661         printf("Key has comment '%s'\n", comment);
 662
 663         /* Ask the new passphrase (twice). */
 664         if (identity_new_passphrase) {
 665                 passphrase1 = xstrdup(identity_new_passphrase);
 666                 passphrase2 = NULL;
 667         } else {
 668                 passphrase1 =
 669                         read_passphrase("Enter new passphrase (empty for no "
 670                             "passphrase): ", RP_ALLOW_STDIN);
 671                 passphrase2 = read_passphrase("Enter same passphrase again: ",
 672                     RP_ALLOW_STDIN);
 673
 674                 /* Verify that they are the same. */
 675                 if (strcmp(passphrase1, passphrase2) != 0) {
 676                         memset(passphrase1, 0, strlen(passphrase1));
 677                         memset(passphrase2, 0, strlen(passphrase2));
 678                         xfree(passphrase1);
 679                         xfree(passphrase2);
 680                         printf("Pass phrases do not match.  Try again.\n");
 681                         exit(1);
 682                 }
 683                 /* Destroy the other copy. */
 684                 memset(passphrase2, 0, strlen(passphrase2));
 685                 xfree(passphrase2);
 686         }
 687
 688         /* Save the file using the new passphrase. */
 689         if (!key_save_private(private, identity_file, passphrase1, comment)) {
 690                 printf("Saving the key failed: %s.\n", identity_file);
 691                 memset(passphrase1, 0, strlen(passphrase1));
 692                 xfree(passphrase1);
 693                 key_free(private);
 694                 xfree(comment);
 695                 exit(1);
 696         }
 697         /* Destroy the passphrase and the copy of the key in memory. */
 698         memset(passphrase1, 0, strlen(passphrase1));
 699         xfree(passphrase1);
 700         key_free(private);               /* Destroys contents */
 701         xfree(comment);
 702
 703         printf("Your identification has been saved with the new passphrase.\n");
 704         exit(0);
 705 }
 706
 707 /*
 708  * Change the comment of a private key file.
 709  */
 710 static void
 711 do_change_comment(struct passwd *pw)
 712 {
 713         char new_comment[1024], *comment, *passphrase;
 714         Key *private;
 715         Key *public;
 716         struct stat st;
 717         FILE *f;
 718         int fd;
 719
 720         if (!have_identity)
 721                 ask_filename(pw, "Enter file in which the key is");
 722         if (stat(identity_file, &st) < 0) {
 723                 perror(identity_file);
 724                 exit(1);
 725         }
 726         private = key_load_private(identity_file, "", &comment);
 727         if (private == NULL) {
 728                 if (identity_passphrase)
 729                         passphrase = xstrdup(identity_passphrase);
 730                 else if (identity_new_passphrase)
 731                         passphrase = xstrdup(identity_new_passphrase);
 732                 else
 733                         passphrase = read_passphrase("Enter passphrase: ",
 734                             RP_ALLOW_STDIN);
 735                 /* Try to load using the passphrase. */
 736                 private = key_load_private(identity_file, passphrase, &comment);
 737                 if (private == NULL) {
 738                         memset(passphrase, 0, strlen(passphrase));
 739                         xfree(passphrase);
 740                         printf("Bad passphrase.\n");
 741                         exit(1);
 742                 }
 743         } else {
 744                 passphrase = xstrdup("");
 745         }
 746         if (private->type != KEY_RSA1) {
 747                 fprintf(stderr, "Comments are only supported for RSA1 keys.\n");
 748                 key_free(private);
 749                 exit(1);
 750         }
 751         printf("Key now has comment '%s'\n", comment);
 752
 753         if (identity_comment) {
 754                 strlcpy(new_comment, identity_comment, sizeof(new_comment));
 755         } else {
 756                 printf("Enter new comment: ");
 757                 fflush(stdout);
 758                 if (!fgets(new_comment, sizeof(new_comment), stdin)) {
 759                         memset(passphrase, 0, strlen(passphrase));
 760                         key_free(private);
 761                         exit(1);
 762                 }
 763                 if (strchr(new_comment, '\n'))
 764                         *strchr(new_comment, '\n') = 0;
 765         }
 766
 767         /* Save the file using the new passphrase. */
 768         if (!key_save_private(private, identity_file, passphrase, new_comment)) {
 769                 printf("Saving the key failed: %s.\n", identity_file);
 770                 memset(passphrase, 0, strlen(passphrase));
 771                 xfree(passphrase);
 772                 key_free(private);
 773                 xfree(comment);
 774                 exit(1);
 775         }
 776         memset(passphrase, 0, strlen(passphrase));
 777         xfree(passphrase);
 778         public = key_from_private(private);
 779         key_free(private);
 780
 781         strlcat(identity_file, ".pub", sizeof(identity_file));
 782         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 783         if (fd == -1) {
 784                 printf("Could not save your public key in %s\n", identity_file);
 785                 exit(1);
 786         }
 787         f = fdopen(fd, "w");
 788         if (f == NULL) {
 789                 printf("fdopen %s failed", identity_file);
 790                 exit(1);
 791         }
 792         if (!key_write(public, f))
 793                 fprintf(stderr, "write key failed");
 794         key_free(public);
 795         fprintf(f, " %s\n", new_comment);
 796         fclose(f);
 797
 798         xfree(comment);
 799
 800         printf("The comment in your key file has been changed.\n");
 801         exit(0);
 802 }
 803
 804 static void
 805 usage(void)
 806 {
 807         fprintf(stderr, "Usage: %s [options]\n", __progname);
 808         fprintf(stderr, "Options:\n");
 809         fprintf(stderr, "  -b bits     Number of bits in the key to create.\n");
 810         fprintf(stderr, "  -c          Change comment in private and public key files.\n");
 811         fprintf(stderr, "  -e          Convert OpenSSH to IETF SECSH key file.\n");
 812         fprintf(stderr, "  -f filename Filename of the key file.\n");
 813         fprintf(stderr, "  -i          Convert IETF SECSH to OpenSSH key file.\n");
 814         fprintf(stderr, "  -l          Show fingerprint of key file.\n");
 815         fprintf(stderr, "  -p          Change passphrase of private key file.\n");
 816         fprintf(stderr, "  -q          Quiet.\n");
 817         fprintf(stderr, "  -y          Read private key file and print public key.\n");
 818         fprintf(stderr, "  -t type     Specify type of key to create.\n");
 819         fprintf(stderr, "  -B          Show bubblebabble digest of key file.\n");
 820         fprintf(stderr, "  -C comment  Provide new comment.\n");
 821         fprintf(stderr, "  -N phrase   Provide new passphrase.\n");
 822         fprintf(stderr, "  -P phrase   Provide old passphrase.\n");
 823 #ifdef SMARTCARD
 824         fprintf(stderr, "  -D reader   Download public key from smartcard.\n");
 825         fprintf(stderr, "  -U reader   Upload private key to smartcard.\n");
 826 #endif /* SMARTCARD */
 827
 828         exit(1);
 829 }
 830
 831 /*
 832  * Main program for key management.
 833  */
 834 int
 835 main(int ac, char **av)
 836 {
 837         char dotsshdir[MAXPATHLEN], comment[1024], *passphrase1, *passphrase2;
 838         char *reader_id = NULL;
 839         Key *private, *public;
 840         struct passwd *pw;
 841         struct stat st;
 842         int opt, type, fd, download = 0;
 843         FILE *f;
 844
 845         extern int optind;
 846         extern char *optarg;
 847
 848         __progname = get_progname(av[0]);
 849         init_rng();
 850         seed_rng();
 851
 852         SSLeay_add_all_algorithms();
 853
 854         /* we need this for the home * directory.  */
 855         pw = getpwuid(getuid());
 856         if (!pw) {
 857                 printf("You don't exist, go away!\n");
 858                 exit(1);
 859         }
 860         if (gethostname(hostname, sizeof(hostname)) < 0) {
 861                 perror("gethostname");
 862                 exit(1);
 863         }
 864
 865         while ((opt = getopt(ac, av, "deiqpclBRxXyb:f:t:U:D:P:N:C:")) != -1) {
 866                 switch (opt) {
 867                 case 'b':
 868                         bits = atoi(optarg);
 869                         if (bits < 512 || bits > 32768) {
 870                                 printf("Bits has bad value.\n");
 871                                 exit(1);
 872                         }
 873                         break;
 874                 case 'l':
 875                         print_fingerprint = 1;
 876                         break;
 877                 case 'B':
 878                         print_bubblebabble = 1;
 879                         break;
 880                 case 'p':
 881                         change_passphrase = 1;
 882                         break;
 883                 case 'c':
 884                         change_comment = 1;
 885                         break;
 886                 case 'f':
 887                         strlcpy(identity_file, optarg, sizeof(identity_file));
 888                         have_identity = 1;
 889                         break;
 890                 case 'P':
 891                         identity_passphrase = optarg;
 892                         break;
 893                 case 'N':
 894                         identity_new_passphrase = optarg;
 895                         break;
 896                 case 'C':
 897                         identity_comment = optarg;
 898                         break;
 899                 case 'q':
 900                         quiet = 1;
 901                         break;
 902                 case 'R':
 903                         /* unused */
 904                         exit(0);
 905                         break;
 906                 case 'e':
 907                 case 'x':
 908                         /* export key */
 909                         convert_to_ssh2 = 1;
 910                         break;
 911                 case 'i':
 912                 case 'X':
 913                         /* import key */
 914                         convert_from_ssh2 = 1;
 915                         break;
 916                 case 'y':
 917                         print_public = 1;
 918                         break;
 919                 case 'd':
 920                         key_type_name = "dsa";
 921                         break;
 922                 case 't':
 923                         key_type_name = optarg;
 924                         break;
 925                 case 'D':
 926                         download = 1;
 927                 case 'U':
 928                         reader_id = optarg;
 929                         break;
 930                 case '?':
 931                 default:
 932                         usage();
 933                 }
 934         }
 935         if (optind < ac) {
 936                 printf("Too many arguments.\n");
 937                 usage();
 938         }
 939         if (change_passphrase && change_comment) {
 940                 printf("Can only have one of -p and -c.\n");
 941                 usage();
 942         }
 943         if (print_fingerprint || print_bubblebabble)
 944                 do_fingerprint(pw);
 945         if (change_passphrase)
 946                 do_change_passphrase(pw);
 947         if (change_comment)
 948                 do_change_comment(pw);
 949         if (convert_to_ssh2)
 950                 do_convert_to_ssh2(pw);
 951         if (convert_from_ssh2)
 952                 do_convert_from_ssh2(pw);
 953         if (print_public)
 954                 do_print_public(pw);
 955         if (reader_id != NULL) {
 956 #ifdef SMARTCARD
 957                 if (download)
 958                         do_download(pw, reader_id);
 959                 else
 960                         do_upload(pw, reader_id);
 961 #else /* SMARTCARD */
 962                 fatal("no support for smartcards.");
 963 #endif /* SMARTCARD */
 964         }
 965
 966         arc4random_stir();
 967
 968         if (key_type_name == NULL) {
 969                 printf("You must specify a key type (-t).\n");
 970                 usage();
 971         }
 972         type = key_type_from_name(key_type_name);
 973         if (type == KEY_UNSPEC) {
 974                 fprintf(stderr, "unknown key type %s\n", key_type_name);
 975                 exit(1);
 976         }
 977         if (!quiet)
 978                 printf("Generating public/private %s key pair.\n", key_type_name);
 979         private = key_generate(type, bits);
 980         if (private == NULL) {
 981                 fprintf(stderr, "key_generate failed");
 982                 exit(1);
 983         }
 984         public  = key_from_private(private);
 985
 986         if (!have_identity)
 987                 ask_filename(pw, "Enter file in which to save the key");
 988
 989         /* Create ~/.ssh directory if it doesn\'t already exist. */
 990         snprintf(dotsshdir, sizeof dotsshdir, "%s/%s", pw->pw_dir, _PATH_SSH_USER_DIR);
 991         if (strstr(identity_file, dotsshdir) != NULL &&
 992             stat(dotsshdir, &st) < 0) {
 993                 if (mkdir(dotsshdir, 0700) < 0)
 994                         error("Could not create directory '%s'.", dotsshdir);
 995                 else if (!quiet)
 996                         printf("Created directory '%s'.\n", dotsshdir);
 997         }
 998         /* If the file already exists, ask the user to confirm. */
 999         if (stat(identity_file, &st) >= 0) {
1000                 char yesno[3];
1001                 printf("%s already exists.\n", identity_file);
1002                 printf("Overwrite (y/n)? ");
1003                 fflush(stdout);
1004                 if (fgets(yesno, sizeof(yesno), stdin) == NULL)
1005                         exit(1);
1006                 if (yesno[0] != 'y' && yesno[0] != 'Y')
1007                         exit(1);
1008         }
1009         /* Ask for a passphrase (twice). */
1010         if (identity_passphrase)
1011                 passphrase1 = xstrdup(identity_passphrase);
1012         else if (identity_new_passphrase)
1013                 passphrase1 = xstrdup(identity_new_passphrase);
1014         else {
1015 passphrase_again:
1016                 passphrase1 =
1017                         read_passphrase("Enter passphrase (empty for no "
1018                             "passphrase): ", RP_ALLOW_STDIN);
1019                 passphrase2 = read_passphrase("Enter same passphrase again: ",
1020                     RP_ALLOW_STDIN);
1021                 if (strcmp(passphrase1, passphrase2) != 0) {
1022                         /*
1023                          * The passphrases do not match.  Clear them and
1024                          * retry.
1025                          */
1026                         memset(passphrase1, 0, strlen(passphrase1));
1027                         memset(passphrase2, 0, strlen(passphrase2));
1028                         xfree(passphrase1);
1029                         xfree(passphrase2);
1030                         printf("Passphrases do not match.  Try again.\n");
1031                         goto passphrase_again;
1032                 }
1033                 /* Clear the other copy of the passphrase. */
1034                 memset(passphrase2, 0, strlen(passphrase2));
1035                 xfree(passphrase2);
1036         }
1037
1038         if (identity_comment) {
1039                 strlcpy(comment, identity_comment, sizeof(comment));
1040         } else {
1041                 /* Create default commend field for the passphrase. */
1042                 snprintf(comment, sizeof comment, "%s@%s", pw->pw_name, hostname);
1043         }
1044
1045         /* Save the key with the given passphrase and comment. */
1046         if (!key_save_private(private, identity_file, passphrase1, comment)) {
1047                 printf("Saving the key failed: %s.\n", identity_file);
1048                 memset(passphrase1, 0, strlen(passphrase1));
1049                 xfree(passphrase1);
1050                 exit(1);
1051         }
1052         /* Clear the passphrase. */
1053         memset(passphrase1, 0, strlen(passphrase1));
1054         xfree(passphrase1);
1055
1056         /* Clear the private key and the random number generator. */
1057         key_free(private);
1058         arc4random_stir();
1059
1060         if (!quiet)
1061                 printf("Your identification has been saved in %s.\n", identity_file);
1062
1063         strlcat(identity_file, ".pub", sizeof(identity_file));
1064         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
1065         if (fd == -1) {
1066                 printf("Could not save your public key in %s\n", identity_file);
1067                 exit(1);
1068         }
1069         f = fdopen(fd, "w");
1070         if (f == NULL) {
1071                 printf("fdopen %s failed", identity_file);
1072                 exit(1);
1073         }
1074         if (!key_write(public, f))
1075                 fprintf(stderr, "write key failed");
1076         fprintf(f, " %s\n", comment);
1077         fclose(f);
1078
1079         if (!quiet) {
1080                 char *fp = key_fingerprint(public, SSH_FP_MD5, SSH_FP_HEX);
1081                 printf("Your public key has been saved in %s.\n",
1082                     identity_file);
1083                 printf("The key fingerprint is:\n");
1084                 printf("%s %s\n", fp, comment);
1085                 xfree(fp);
1086         }
1087
1088         key_free(public);
1089         exit(0);
1090 }