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 1.93 2002/02/24 19:14:59 markus Exp $");
  16
  17 #include <openssl/evp.h>
  18 #include <openssl/pem.h>
  19
  20 #include "xmalloc.h"
  21 #include "key.h"
  22 #include "rsa.h"
  23 #include "authfile.h"
  24 #include "uuencode.h"
  25 #include "buffer.h"
  26 #include "bufaux.h"
  27 #include "pathnames.h"
  28 #include "log.h"
  29 #include "readpass.h"
  30
  31 #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         if (key_type_name == NULL)
  94                 name = _PATH_SSH_CLIENT_ID_RSA;
  95         else
  96                 switch (key_type_from_name(key_type_name)) {
  97                 case KEY_RSA1:
  98                         name = _PATH_SSH_CLIENT_IDENTITY;
  99                         break;
 100                 case KEY_DSA:
 101                         name = _PATH_SSH_CLIENT_ID_DSA;
 102                         break;
 103                 case KEY_RSA:
 104                         name = _PATH_SSH_CLIENT_ID_RSA;
 105                         break;
 106                 default:
 107                         fprintf(stderr, "bad key type");
 108                         exit(1);
 109                         break;
 110                 }
 111
 112         snprintf(identity_file, sizeof(identity_file), "%s/%s", pw->pw_dir, name);
 113         fprintf(stderr, "%s (%s): ", prompt, identity_file);
 114         fflush(stderr);
 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         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 (key_to_blob(k, &blob, &len) <= 0) {
 170                 fprintf(stderr, "key_to_blob failed\n");
 171                 exit(1);
 172         }
 173         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_BEGIN);
 174         fprintf(stdout,
 175             "Comment: \"%d-bit %s, converted from OpenSSH by %s@%s\"\n",
 176             key_size(k), key_type(k),
 177             pw->pw_name, hostname);
 178         dump_base64(stdout, blob, len);
 179         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_END);
 180         key_free(k);
 181         xfree(blob);
 182         exit(0);
 183 }
 184
 185 static void
 186 buffer_get_bignum_bits(Buffer *b, BIGNUM *value)
 187 {
 188         int bits = buffer_get_int(b);
 189         int bytes = (bits + 7) / 8;
 190
 191         if (buffer_len(b) < bytes)
 192                 fatal("buffer_get_bignum_bits: input buffer too small: "
 193                     "need %d have %d", bytes, buffer_len(b));
 194         BN_bin2bn(buffer_ptr(b), bytes, value);
 195         buffer_consume(b, bytes);
 196 }
 197
 198 static Key *
 199 do_convert_private_ssh2_from_blob(u_char *blob, u_int blen)
 200 {
 201         Buffer b;
 202         Key *key = NULL;
 203         char *type, *cipher;
 204         u_char *sig, data[] = "abcde12345";
 205         int magic, rlen, ktype, i1, i2, i3, i4;
 206         u_int slen;
 207         u_long e;
 208
 209         buffer_init(&b);
 210         buffer_append(&b, blob, blen);
 211
 212         magic  = buffer_get_int(&b);
 213         if (magic != SSH_COM_PRIVATE_KEY_MAGIC) {
 214                 error("bad magic 0x%x != 0x%x", magic, SSH_COM_PRIVATE_KEY_MAGIC);
 215                 buffer_free(&b);
 216                 return NULL;
 217         }
 218         i1 = buffer_get_int(&b);
 219         type   = buffer_get_string(&b, NULL);
 220         cipher = buffer_get_string(&b, NULL);
 221         i2 = buffer_get_int(&b);
 222         i3 = buffer_get_int(&b);
 223         i4 = buffer_get_int(&b);
 224         debug("ignore (%d %d %d %d)", i1,i2,i3,i4);
 225         if (strcmp(cipher, "none") != 0) {
 226                 error("unsupported cipher %s", cipher);
 227                 xfree(cipher);
 228                 buffer_free(&b);
 229                 xfree(type);
 230                 return NULL;
 231         }
 232         xfree(cipher);
 233
 234         if (strstr(type, "dsa")) {
 235                 ktype = KEY_DSA;
 236         } else if (strstr(type, "rsa")) {
 237                 ktype = KEY_RSA;
 238         } else {
 239                 xfree(type);
 240                 return NULL;
 241         }
 242         key = key_new_private(ktype);
 243         xfree(type);
 244
 245         switch (key->type) {
 246         case KEY_DSA:
 247                 buffer_get_bignum_bits(&b, key->dsa->p);
 248                 buffer_get_bignum_bits(&b, key->dsa->g);
 249                 buffer_get_bignum_bits(&b, key->dsa->q);
 250                 buffer_get_bignum_bits(&b, key->dsa->pub_key);
 251                 buffer_get_bignum_bits(&b, key->dsa->priv_key);
 252                 break;
 253         case KEY_RSA:
 254                 e  = buffer_get_char(&b);
 255                 debug("e %lx", e);
 256                 if (e < 30) {
 257                         e <<= 8;
 258                         e += buffer_get_char(&b);
 259                         debug("e %lx", e);
 260                         e <<= 8;
 261                         e += buffer_get_char(&b);
 262                         debug("e %lx", e);
 263                 }
 264                 if (!BN_set_word(key->rsa->e, e)) {
 265                         buffer_free(&b);
 266                         key_free(key);
 267                         return NULL;
 268                 }
 269                 buffer_get_bignum_bits(&b, key->rsa->d);
 270                 buffer_get_bignum_bits(&b, key->rsa->n);
 271                 buffer_get_bignum_bits(&b, key->rsa->iqmp);
 272                 buffer_get_bignum_bits(&b, key->rsa->q);
 273                 buffer_get_bignum_bits(&b, key->rsa->p);
 274                 rsa_generate_additional_parameters(key->rsa);
 275                 break;
 276         }
 277         rlen = buffer_len(&b);
 278         if (rlen != 0)
 279                 error("do_convert_private_ssh2_from_blob: "
 280                     "remaining bytes in key blob %d", rlen);
 281         buffer_free(&b);
 282
 283         /* try the key */
 284         key_sign(key, &sig, &slen, data, sizeof(data));
 285         key_verify(key, sig, slen, data, sizeof(data));
 286         xfree(sig);
 287         return key;
 288 }
 289
 290 static void
 291 do_convert_from_ssh2(struct passwd *pw)
 292 {
 293         Key *k;
 294         int blen;
 295         char line[1024], *p;
 296         u_char blob[8096];
 297         char encoded[8096];
 298         struct stat st;
 299         int escaped = 0, private = 0, ok;
 300         FILE *fp;
 301
 302         if (!have_identity)
 303                 ask_filename(pw, "Enter file in which the key is");
 304         if (stat(identity_file, &st) < 0) {
 305                 perror(identity_file);
 306                 exit(1);
 307         }
 308         fp = fopen(identity_file, "r");
 309         if (fp == NULL) {
 310                 perror(identity_file);
 311                 exit(1);
 312         }
 313         encoded[0] = '\0';
 314         while (fgets(line, sizeof(line), fp)) {
 315                 if (!(p = strchr(line, '\n'))) {
 316                         fprintf(stderr, "input line too long.\n");
 317                         exit(1);
 318                 }
 319                 if (p > line && p[-1] == '\\')
 320                         escaped++;
 321                 if (strncmp(line, "----", 4) == 0 ||
 322                     strstr(line, ": ") != NULL) {
 323                         if (strstr(line, SSH_COM_PRIVATE_BEGIN) != NULL)
 324                                 private = 1;
 325                         if (strstr(line, " END ") != NULL) {
 326                                 break;
 327                         }
 328                         /* fprintf(stderr, "ignore: %s", line); */
 329                         continue;
 330                 }
 331                 if (escaped) {
 332                         escaped--;
 333                         /* fprintf(stderr, "escaped: %s", line); */
 334                         continue;
 335                 }
 336                 *p = '\0';
 337                 strlcat(encoded, line, sizeof(encoded));
 338         }
 339         blen = uudecode(encoded, blob, sizeof(blob));
 340         if (blen < 0) {
 341                 fprintf(stderr, "uudecode failed.\n");
 342                 exit(1);
 343         }
 344         k = private ?
 345             do_convert_private_ssh2_from_blob(blob, blen) :
 346             key_from_blob(blob, blen);
 347         if (k == NULL) {
 348                 fprintf(stderr, "decode blob failed.\n");
 349                 exit(1);
 350         }
 351         ok = private ?
 352             (k->type == KEY_DSA ?
 353                  PEM_write_DSAPrivateKey(stdout, k->dsa, NULL, NULL, 0, NULL, NULL) :
 354                  PEM_write_RSAPrivateKey(stdout, k->rsa, NULL, NULL, 0, NULL, NULL)) :
 355             key_write(k, stdout);
 356         if (!ok) {
 357                 fprintf(stderr, "key write failed");
 358                 exit(1);
 359         }
 360         key_free(k);
 361         if (!private)
 362                 fprintf(stdout, "\n");
 363         fclose(fp);
 364         exit(0);
 365 }
 366
 367 static void
 368 do_print_public(struct passwd *pw)
 369 {
 370         Key *prv;
 371         struct stat st;
 372
 373         if (!have_identity)
 374                 ask_filename(pw, "Enter file in which the key is");
 375         if (stat(identity_file, &st) < 0) {
 376                 perror(identity_file);
 377                 exit(1);
 378         }
 379         prv = load_identity(identity_file);
 380         if (prv == NULL) {
 381                 fprintf(stderr, "load failed\n");
 382                 exit(1);
 383         }
 384         if (!key_write(prv, stdout))
 385                 fprintf(stderr, "key_write failed");
 386         key_free(prv);
 387         fprintf(stdout, "\n");
 388         exit(0);
 389 }
 390
 391 #ifdef SMARTCARD
 392 #define NUM_RSA_KEY_ELEMENTS 5+1
 393 #define COPY_RSA_KEY(x, i) \
 394         do { \
 395                 len = BN_num_bytes(prv->rsa->x); \
 396                 elements[i] = xmalloc(len); \
 397                 debug("#bytes %d", len); \
 398                 if (BN_bn2bin(prv->rsa->x, elements[i]) < 0) \
 399                         goto done; \
 400         } while (0)
 401
 402 static int
 403 get_AUT0(char *aut0)
 404 {
 405         EVP_MD *evp_md = EVP_sha1();
 406         EVP_MD_CTX md;
 407         char *pass;
 408
 409         pass = read_passphrase("Enter passphrase for smartcard: ", RP_ALLOW_STDIN);
 410         if (pass == NULL)
 411                 return -1;
 412         EVP_DigestInit(&md, evp_md);
 413         EVP_DigestUpdate(&md, pass, strlen(pass));
 414         EVP_DigestFinal(&md, aut0, NULL);
 415         memset(pass, 0, strlen(pass));
 416         xfree(pass);
 417         return 0;
 418 }
 419
 420 static void
 421 do_upload(struct passwd *pw, const char *sc_reader_id)
 422 {
 423         Key *prv = NULL;
 424         struct stat st;
 425         u_char *elements[NUM_RSA_KEY_ELEMENTS];
 426         u_char key_fid[2];
 427         u_char DEFAUT0[] = {0xad, 0x9f, 0x61, 0xfe, 0xfa, 0x20, 0xce, 0x63};
 428         u_char AUT0[EVP_MAX_MD_SIZE];
 429         int len, status = 1, i, fd = -1, ret;
 430         int sw = 0, cla = 0x00;
 431
 432         for (i = 0; i < NUM_RSA_KEY_ELEMENTS; i++)
 433                 elements[i] = NULL;
 434         if (!have_identity)
 435                 ask_filename(pw, "Enter file in which the key is");
 436         if (stat(identity_file, &st) < 0) {
 437                 perror(identity_file);
 438                 goto done;
 439         }
 440         prv = load_identity(identity_file);
 441         if (prv == NULL) {
 442                 error("load failed");
 443                 goto done;
 444         }
 445         COPY_RSA_KEY(q, 0);
 446         COPY_RSA_KEY(p, 1);
 447         COPY_RSA_KEY(iqmp, 2);
 448         COPY_RSA_KEY(dmq1, 3);
 449         COPY_RSA_KEY(dmp1, 4);
 450         COPY_RSA_KEY(n, 5);
 451         len = BN_num_bytes(prv->rsa->n);
 452         fd = sectok_friendly_open(sc_reader_id, STONOWAIT, &sw);
 453         if (fd < 0) {
 454                 error("sectok_open failed: %s", sectok_get_sw(sw));
 455                 goto done;
 456         }
 457         if (! sectok_cardpresent(fd)) {
 458                 error("smartcard in reader %s not present",
 459                     sc_reader_id);
 460                 goto done;
 461         }
 462         ret = sectok_reset(fd, 0, NULL, &sw);
 463         if (ret <= 0) {
 464                 error("sectok_reset failed: %s", sectok_get_sw(sw));
 465                 goto done;
 466         }
 467         if ((cla = cyberflex_inq_class(fd)) < 0) {
 468                 error("cyberflex_inq_class failed");
 469                 goto done;
 470         }
 471         memcpy(AUT0, DEFAUT0, sizeof(DEFAUT0));
 472         if (cyberflex_verify_AUT0(fd, cla, AUT0, sizeof(DEFAUT0)) < 0) {
 473                 if (get_AUT0(AUT0) < 0 ||
 474                     cyberflex_verify_AUT0(fd, cla, AUT0, sizeof(DEFAUT0)) < 0) {
 475                         error("cyberflex_verify_AUT0 failed");
 476                         goto done;
 477                 }
 478         }
 479         key_fid[0] = 0x00;
 480         key_fid[1] = 0x12;
 481         if (cyberflex_load_rsa_priv(fd, cla, key_fid, 5, 8*len, elements,
 482             &sw) < 0) {
 483                 error("cyberflex_load_rsa_priv failed: %s", sectok_get_sw(sw));
 484                 goto done;
 485         }
 486         if (!sectok_swOK(sw))
 487                 goto done;
 488         log("cyberflex_load_rsa_priv done");
 489         key_fid[0] = 0x73;
 490         key_fid[1] = 0x68;
 491         if (cyberflex_load_rsa_pub(fd, cla, key_fid, len, elements[5],
 492             &sw) < 0) {
 493                 error("cyberflex_load_rsa_pub failed: %s", sectok_get_sw(sw));
 494                 goto done;
 495         }
 496         if (!sectok_swOK(sw))
 497                 goto done;
 498         log("cyberflex_load_rsa_pub done");
 499         status = 0;
 500         log("loading key done");
 501 done:
 502
 503         memset(elements[0], '\0', BN_num_bytes(prv->rsa->q));
 504         memset(elements[1], '\0', BN_num_bytes(prv->rsa->p));
 505         memset(elements[2], '\0', BN_num_bytes(prv->rsa->iqmp));
 506         memset(elements[3], '\0', BN_num_bytes(prv->rsa->dmq1));
 507         memset(elements[4], '\0', BN_num_bytes(prv->rsa->dmp1));
 508         memset(elements[5], '\0', BN_num_bytes(prv->rsa->n));
 509
 510         if (prv)
 511                 key_free(prv);
 512         for (i = 0; i < NUM_RSA_KEY_ELEMENTS; i++)
 513                 if (elements[i])
 514                         xfree(elements[i]);
 515         if (fd != -1)
 516                 sectok_close(fd);
 517         exit(status);
 518 }
 519
 520 static void
 521 do_download(struct passwd *pw, const char *sc_reader_id)
 522 {
 523         Key *pub = NULL;
 524
 525         pub = sc_get_key(sc_reader_id);
 526         if (pub == NULL)
 527                 fatal("cannot read public key from smartcard");
 528         key_write(pub, stdout);
 529         key_free(pub);
 530         fprintf(stdout, "\n");
 531         exit(0);
 532 }
 533 #endif /* SMARTCARD */
 534
 535 static void
 536 do_fingerprint(struct passwd *pw)
 537 {
 538         FILE *f;
 539         Key *public;
 540         char *comment = NULL, *cp, *ep, line[16*1024], *fp;
 541         int i, skip = 0, num = 1, invalid = 1;
 542         enum fp_rep rep;
 543         enum fp_type fptype;
 544         struct stat st;
 545
 546         fptype = print_bubblebabble ? SSH_FP_SHA1 : SSH_FP_MD5;
 547         rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_HEX;
 548
 549         if (!have_identity)
 550                 ask_filename(pw, "Enter file in which the key is");
 551         if (stat(identity_file, &st) < 0) {
 552                 perror(identity_file);
 553                 exit(1);
 554         }
 555         public = key_load_public(identity_file, &comment);
 556         if (public != NULL) {
 557                 fp = key_fingerprint(public, fptype, rep);
 558                 printf("%d %s %s\n", key_size(public), fp, comment);
 559                 key_free(public);
 560                 xfree(comment);
 561                 xfree(fp);
 562                 exit(0);
 563         }
 564         if (comment)
 565                 xfree(comment);
 566
 567         f = fopen(identity_file, "r");
 568         if (f != NULL) {
 569                 while (fgets(line, sizeof(line), f)) {
 570                         i = strlen(line) - 1;
 571                         if (line[i] != '\n') {
 572                                 error("line %d too long: %.40s...", num, line);
 573                                 skip = 1;
 574                                 continue;
 575                         }
 576                         num++;
 577                         if (skip) {
 578                                 skip = 0;
 579                                 continue;
 580                         }
 581                         line[i] = '\0';
 582
 583                         /* Skip leading whitespace, empty and comment lines. */
 584                         for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
 585                                 ;
 586                         if (!*cp || *cp == '\n' || *cp == '#')
 587                                 continue ;
 588                         i = strtol(cp, &ep, 10);
 589                         if (i == 0 || ep == NULL || (*ep != ' ' && *ep != '\t')) {
 590                                 int quoted = 0;
 591                                 comment = cp;
 592                                 for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
 593                                         if (*cp == '\\' && cp[1] == '"')
 594                                                 cp++;   /* Skip both */
 595                                         else if (*cp == '"')
 596                                                 quoted = !quoted;
 597                                 }
 598                                 if (!*cp)
 599                                         continue;
 600                                 *cp++ = '\0';
 601                         }
 602                         ep = cp;
 603                         public = key_new(KEY_RSA1);
 604                         if (key_read(public, &cp) != 1) {
 605                                 cp = ep;
 606                                 key_free(public);
 607                                 public = key_new(KEY_UNSPEC);
 608                                 if (key_read(public, &cp) != 1) {
 609                                         key_free(public);
 610                                         continue;
 611                                 }
 612                         }
 613                         comment = *cp ? cp : comment;
 614                         fp = key_fingerprint(public, fptype, rep);
 615                         printf("%d %s %s\n", key_size(public), fp,
 616                             comment ? comment : "no comment");
 617                         xfree(fp);
 618                         key_free(public);
 619                         invalid = 0;
 620                 }
 621                 fclose(f);
 622         }
 623         if (invalid) {
 624                 printf("%s is not a public key file.\n", identity_file);
 625                 exit(1);
 626         }
 627         exit(0);
 628 }
 629
 630 /*
 631  * Perform changing a passphrase.  The argument is the passwd structure
 632  * for the current user.
 633  */
 634 static void
 635 do_change_passphrase(struct passwd *pw)
 636 {
 637         char *comment;
 638         char *old_passphrase, *passphrase1, *passphrase2;
 639         struct stat st;
 640         Key *private;
 641
 642         if (!have_identity)
 643                 ask_filename(pw, "Enter file in which the key is");
 644         if (stat(identity_file, &st) < 0) {
 645                 perror(identity_file);
 646                 exit(1);
 647         }
 648         /* Try to load the file with empty passphrase. */
 649         private = key_load_private(identity_file, "", &comment);
 650         if (private == NULL) {
 651                 if (identity_passphrase)
 652                         old_passphrase = xstrdup(identity_passphrase);
 653                 else
 654                         old_passphrase =
 655                             read_passphrase("Enter old passphrase: ",
 656                             RP_ALLOW_STDIN);
 657                 private = key_load_private(identity_file, old_passphrase,
 658                     &comment);
 659                 memset(old_passphrase, 0, strlen(old_passphrase));
 660                 xfree(old_passphrase);
 661                 if (private == NULL) {
 662                         printf("Bad passphrase.\n");
 663                         exit(1);
 664                 }
 665         }
 666         printf("Key has comment '%s'\n", comment);
 667
 668         /* Ask the new passphrase (twice). */
 669         if (identity_new_passphrase) {
 670                 passphrase1 = xstrdup(identity_new_passphrase);
 671                 passphrase2 = NULL;
 672         } else {
 673                 passphrase1 =
 674                         read_passphrase("Enter new passphrase (empty for no "
 675                             "passphrase): ", RP_ALLOW_STDIN);
 676                 passphrase2 = read_passphrase("Enter same passphrase again: ",
 677                     RP_ALLOW_STDIN);
 678
 679                 /* Verify that they are the same. */
 680                 if (strcmp(passphrase1, passphrase2) != 0) {
 681                         memset(passphrase1, 0, strlen(passphrase1));
 682                         memset(passphrase2, 0, strlen(passphrase2));
 683                         xfree(passphrase1);
 684                         xfree(passphrase2);
 685                         printf("Pass phrases do not match.  Try again.\n");
 686                         exit(1);
 687                 }
 688                 /* Destroy the other copy. */
 689                 memset(passphrase2, 0, strlen(passphrase2));
 690                 xfree(passphrase2);
 691         }
 692
 693         /* Save the file using the new passphrase. */
 694         if (!key_save_private(private, identity_file, passphrase1, comment)) {
 695                 printf("Saving the key failed: %s.\n", identity_file);
 696                 memset(passphrase1, 0, strlen(passphrase1));
 697                 xfree(passphrase1);
 698                 key_free(private);
 699                 xfree(comment);
 700                 exit(1);
 701         }
 702         /* Destroy the passphrase and the copy of the key in memory. */
 703         memset(passphrase1, 0, strlen(passphrase1));
 704         xfree(passphrase1);
 705         key_free(private);               /* Destroys contents */
 706         xfree(comment);
 707
 708         printf("Your identification has been saved with the new passphrase.\n");
 709         exit(0);
 710 }
 711
 712 /*
 713  * Change the comment of a private key file.
 714  */
 715 static void
 716 do_change_comment(struct passwd *pw)
 717 {
 718         char new_comment[1024], *comment, *passphrase;
 719         Key *private;
 720         Key *public;
 721         struct stat st;
 722         FILE *f;
 723         int fd;
 724
 725         if (!have_identity)
 726                 ask_filename(pw, "Enter file in which the key is");
 727         if (stat(identity_file, &st) < 0) {
 728                 perror(identity_file);
 729                 exit(1);
 730         }
 731         private = key_load_private(identity_file, "", &comment);
 732         if (private == NULL) {
 733                 if (identity_passphrase)
 734                         passphrase = xstrdup(identity_passphrase);
 735                 else if (identity_new_passphrase)
 736                         passphrase = xstrdup(identity_new_passphrase);
 737                 else
 738                         passphrase = read_passphrase("Enter passphrase: ",
 739                             RP_ALLOW_STDIN);
 740                 /* Try to load using the passphrase. */
 741                 private = key_load_private(identity_file, passphrase, &comment);
 742                 if (private == NULL) {
 743                         memset(passphrase, 0, strlen(passphrase));
 744                         xfree(passphrase);
 745                         printf("Bad passphrase.\n");
 746                         exit(1);
 747                 }
 748         } else {
 749                 passphrase = xstrdup("");
 750         }
 751         if (private->type != KEY_RSA1) {
 752                 fprintf(stderr, "Comments are only supported for RSA1 keys.\n");
 753                 key_free(private);
 754                 exit(1);
 755         }
 756         printf("Key now has comment '%s'\n", comment);
 757
 758         if (identity_comment) {
 759                 strlcpy(new_comment, identity_comment, sizeof(new_comment));
 760         } else {
 761                 printf("Enter new comment: ");
 762                 fflush(stdout);
 763                 if (!fgets(new_comment, sizeof(new_comment), stdin)) {
 764                         memset(passphrase, 0, strlen(passphrase));
 765                         key_free(private);
 766                         exit(1);
 767                 }
 768                 if (strchr(new_comment, '\n'))
 769                         *strchr(new_comment, '\n') = 0;
 770         }
 771
 772         /* Save the file using the new passphrase. */
 773         if (!key_save_private(private, identity_file, passphrase, new_comment)) {
 774                 printf("Saving the key failed: %s.\n", identity_file);
 775                 memset(passphrase, 0, strlen(passphrase));
 776                 xfree(passphrase);
 777                 key_free(private);
 778                 xfree(comment);
 779                 exit(1);
 780         }
 781         memset(passphrase, 0, strlen(passphrase));
 782         xfree(passphrase);
 783         public = key_from_private(private);
 784         key_free(private);
 785
 786         strlcat(identity_file, ".pub", sizeof(identity_file));
 787         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 788         if (fd == -1) {
 789                 printf("Could not save your public key in %s\n", identity_file);
 790                 exit(1);
 791         }
 792         f = fdopen(fd, "w");
 793         if (f == NULL) {
 794                 printf("fdopen %s failed", identity_file);
 795                 exit(1);
 796         }
 797         if (!key_write(public, f))
 798                 fprintf(stderr, "write key failed");
 799         key_free(public);
 800         fprintf(f, " %s\n", new_comment);
 801         fclose(f);
 802
 803         xfree(comment);
 804
 805         printf("The comment in your key file has been changed.\n");
 806         exit(0);
 807 }
 808
 809 static void
 810 usage(void)
 811 {
 812         fprintf(stderr, "Usage: %s [options]\n", __progname);
 813         fprintf(stderr, "Options:\n");
 814         fprintf(stderr, "  -b bits     Number of bits in the key to create.\n");
 815         fprintf(stderr, "  -c          Change comment in private and public key files.\n");
 816         fprintf(stderr, "  -e          Convert OpenSSH to IETF SECSH key file.\n");
 817         fprintf(stderr, "  -f filename Filename of the key file.\n");
 818         fprintf(stderr, "  -i          Convert IETF SECSH to OpenSSH key file.\n");
 819         fprintf(stderr, "  -l          Show fingerprint of key file.\n");
 820         fprintf(stderr, "  -p          Change passphrase of private key file.\n");
 821         fprintf(stderr, "  -q          Quiet.\n");
 822         fprintf(stderr, "  -y          Read private key file and print public key.\n");
 823         fprintf(stderr, "  -t type     Specify type of key to create.\n");
 824         fprintf(stderr, "  -B          Show bubblebabble digest of key file.\n");
 825         fprintf(stderr, "  -C comment  Provide new comment.\n");
 826         fprintf(stderr, "  -N phrase   Provide new passphrase.\n");
 827         fprintf(stderr, "  -P phrase   Provide old passphrase.\n");
 828 #ifdef SMARTCARD
 829         fprintf(stderr, "  -D reader   Download public key from smartcard.\n");
 830         fprintf(stderr, "  -U reader   Upload private key to smartcard.\n");
 831 #endif /* SMARTCARD */
 832
 833         exit(1);
 834 }
 835
 836 /*
 837  * Main program for key management.
 838  */
 839 int
 840 main(int ac, char **av)
 841 {
 842         char dotsshdir[MAXPATHLEN], comment[1024], *passphrase1, *passphrase2;
 843         char *reader_id = NULL;
 844         Key *private, *public;
 845         struct passwd *pw;
 846         struct stat st;
 847         int opt, type, fd, download = 0;
 848         FILE *f;
 849
 850         extern int optind;
 851         extern char *optarg;
 852
 853         __progname = get_progname(av[0]);
 854
 855         SSLeay_add_all_algorithms();
 856
 857         /* we need this for the home * directory.  */
 858         pw = getpwuid(getuid());
 859         if (!pw) {
 860                 printf("You don't exist, go away!\n");
 861                 exit(1);
 862         }
 863         if (gethostname(hostname, sizeof(hostname)) < 0) {
 864                 perror("gethostname");
 865                 exit(1);
 866         }
 867
 868         while ((opt = getopt(ac, av, "deiqpclBRxXyb:f:t:U:D:P:N:C:")) != -1) {
 869                 switch (opt) {
 870                 case 'b':
 871                         bits = atoi(optarg);
 872                         if (bits < 512 || bits > 32768) {
 873                                 printf("Bits has bad value.\n");
 874                                 exit(1);
 875                         }
 876                         break;
 877                 case 'l':
 878                         print_fingerprint = 1;
 879                         break;
 880                 case 'B':
 881                         print_bubblebabble = 1;
 882                         break;
 883                 case 'p':
 884                         change_passphrase = 1;
 885                         break;
 886                 case 'c':
 887                         change_comment = 1;
 888                         break;
 889                 case 'f':
 890                         strlcpy(identity_file, optarg, sizeof(identity_file));
 891                         have_identity = 1;
 892                         break;
 893                 case 'P':
 894                         identity_passphrase = optarg;
 895                         break;
 896                 case 'N':
 897                         identity_new_passphrase = optarg;
 898                         break;
 899                 case 'C':
 900                         identity_comment = optarg;
 901                         break;
 902                 case 'q':
 903                         quiet = 1;
 904                         break;
 905                 case 'R':
 906                         /* unused */
 907                         exit(0);
 908                         break;
 909                 case 'e':
 910                 case 'x':
 911                         /* export key */
 912                         convert_to_ssh2 = 1;
 913                         break;
 914                 case 'i':
 915                 case 'X':
 916                         /* import key */
 917                         convert_from_ssh2 = 1;
 918                         break;
 919                 case 'y':
 920                         print_public = 1;
 921                         break;
 922                 case 'd':
 923                         key_type_name = "dsa";
 924                         break;
 925                 case 't':
 926                         key_type_name = optarg;
 927                         break;
 928                 case 'D':
 929                         download = 1;
 930                 case 'U':
 931                         reader_id = optarg;
 932                         break;
 933                 case '?':
 934                 default:
 935                         usage();
 936                 }
 937         }
 938         if (optind < ac) {
 939                 printf("Too many arguments.\n");
 940                 usage();
 941         }
 942         if (change_passphrase && change_comment) {
 943                 printf("Can only have one of -p and -c.\n");
 944                 usage();
 945         }
 946         if (print_fingerprint || print_bubblebabble)
 947                 do_fingerprint(pw);
 948         if (change_passphrase)
 949                 do_change_passphrase(pw);
 950         if (change_comment)
 951                 do_change_comment(pw);
 952         if (convert_to_ssh2)
 953                 do_convert_to_ssh2(pw);
 954         if (convert_from_ssh2)
 955                 do_convert_from_ssh2(pw);
 956         if (print_public)
 957                 do_print_public(pw);
 958         if (reader_id != NULL) {
 959 #ifdef SMARTCARD
 960                 if (download)
 961                         do_download(pw, reader_id);
 962                 else
 963                         do_upload(pw, reader_id);
 964 #else /* SMARTCARD */
 965                 fatal("no support for smartcards.");
 966 #endif /* SMARTCARD */
 967         }
 968
 969         init_rng();
 970         seed_rng();
 971         arc4random_stir();
 972
 973         if (key_type_name == NULL) {
 974                 printf("You must specify a key type (-t).\n");
 975                 usage();
 976         }
 977         type = key_type_from_name(key_type_name);
 978         if (type == KEY_UNSPEC) {
 979                 fprintf(stderr, "unknown key type %s\n", key_type_name);
 980                 exit(1);
 981         }
 982         if (!quiet)
 983                 printf("Generating public/private %s key pair.\n", key_type_name);
 984         private = key_generate(type, bits);
 985         if (private == NULL) {
 986                 fprintf(stderr, "key_generate failed");
 987                 exit(1);
 988         }
 989         public  = key_from_private(private);
 990
 991         if (!have_identity)
 992                 ask_filename(pw, "Enter file in which to save the key");
 993
 994         /* Create ~/.ssh directory if it doesn\'t already exist. */
 995         snprintf(dotsshdir, sizeof dotsshdir, "%s/%s", pw->pw_dir, _PATH_SSH_USER_DIR);
 996         if (strstr(identity_file, dotsshdir) != NULL &&
 997             stat(dotsshdir, &st) < 0) {
 998                 if (mkdir(dotsshdir, 0700) < 0)
 999                         error("Could not create directory '%s'.", dotsshdir);
1000                 else if (!quiet)
1001                         printf("Created directory '%s'.\n", dotsshdir);
1002         }
1003         /* If the file already exists, ask the user to confirm. */
1004         if (stat(identity_file, &st) >= 0) {
1005                 char yesno[3];
1006                 printf("%s already exists.\n", identity_file);
1007                 printf("Overwrite (y/n)? ");
1008                 fflush(stdout);
1009                 if (fgets(yesno, sizeof(yesno), stdin) == NULL)
1010                         exit(1);
1011                 if (yesno[0] != 'y' && yesno[0] != 'Y')
1012                         exit(1);
1013         }
1014         /* Ask for a passphrase (twice). */
1015         if (identity_passphrase)
1016                 passphrase1 = xstrdup(identity_passphrase);
1017         else if (identity_new_passphrase)
1018                 passphrase1 = xstrdup(identity_new_passphrase);
1019         else {
1020 passphrase_again:
1021                 passphrase1 =
1022                         read_passphrase("Enter passphrase (empty for no "
1023                             "passphrase): ", RP_ALLOW_STDIN);
1024                 passphrase2 = read_passphrase("Enter same passphrase again: ",
1025                     RP_ALLOW_STDIN);
1026                 if (strcmp(passphrase1, passphrase2) != 0) {
1027                         /*
1028                          * The passphrases do not match.  Clear them and
1029                          * retry.
1030                          */
1031                         memset(passphrase1, 0, strlen(passphrase1));
1032                         memset(passphrase2, 0, strlen(passphrase2));
1033                         xfree(passphrase1);
1034                         xfree(passphrase2);
1035                         printf("Passphrases do not match.  Try again.\n");
1036                         goto passphrase_again;
1037                 }
1038                 /* Clear the other copy of the passphrase. */
1039                 memset(passphrase2, 0, strlen(passphrase2));
1040                 xfree(passphrase2);
1041         }
1042
1043         if (identity_comment) {
1044                 strlcpy(comment, identity_comment, sizeof(comment));
1045         } else {
1046                 /* Create default commend field for the passphrase. */
1047                 snprintf(comment, sizeof comment, "%s@%s", pw->pw_name, hostname);
1048         }
1049
1050         /* Save the key with the given passphrase and comment. */
1051         if (!key_save_private(private, identity_file, passphrase1, comment)) {
1052                 printf("Saving the key failed: %s.\n", identity_file);
1053                 memset(passphrase1, 0, strlen(passphrase1));
1054                 xfree(passphrase1);
1055                 exit(1);
1056         }
1057         /* Clear the passphrase. */
1058         memset(passphrase1, 0, strlen(passphrase1));
1059         xfree(passphrase1);
1060
1061         /* Clear the private key and the random number generator. */
1062         key_free(private);
1063         arc4random_stir();
1064
1065         if (!quiet)
1066                 printf("Your identification has been saved in %s.\n", identity_file);
1067
1068         strlcat(identity_file, ".pub", sizeof(identity_file));
1069         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
1070         if (fd == -1) {
1071                 printf("Could not save your public key in %s\n", identity_file);
1072                 exit(1);
1073         }
1074         f = fdopen(fd, "w");
1075         if (f == NULL) {
1076                 printf("fdopen %s failed", identity_file);
1077                 exit(1);
1078         }
1079         if (!key_write(public, f))
1080                 fprintf(stderr, "write key failed");
1081         fprintf(f, " %s\n", comment);
1082         fclose(f);
1083
1084         if (!quiet) {
1085                 char *fp = key_fingerprint(public, SSH_FP_MD5, SSH_FP_HEX);
1086                 printf("Your public key has been saved in %s.\n",
1087                     identity_file);
1088                 printf("The key fingerprint is:\n");
1089                 printf("%s %s\n", fp, comment);
1090                 xfree(fp);
1091         }
1092
1093         key_free(public);
1094         exit(0);
1095 }