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 1.77 2001/08/02 15:06:52 jakob 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 /* default to RSA for SSH-1 */
  77 char *key_type_name = "rsa1";
  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         switch (key_type_from_name(key_type_name)) {
  95         case KEY_RSA1:
  96                 name = _PATH_SSH_CLIENT_IDENTITY;
  97                 break;
  98         case KEY_DSA:
  99                 name = _PATH_SSH_CLIENT_ID_DSA;
 100                 break;
 101         case KEY_RSA:
 102                 name = _PATH_SSH_CLIENT_ID_RSA;
 103                 break;
 104         default:
 105                 fprintf(stderr, "bad key type");
 106                 exit(1);
 107                 break;
 108         }
 109         snprintf(identity_file, sizeof(identity_file), "%s/%s", pw->pw_dir, name);
 110         fprintf(stderr, "%s (%s): ", prompt, identity_file);
 111         fflush(stderr);
 112         if (fgets(buf, sizeof(buf), stdin) == NULL)
 113                 exit(1);
 114         if (strchr(buf, '\n'))
 115                 *strchr(buf, '\n') = 0;
 116         if (strcmp(buf, "") != 0)
 117                 strlcpy(identity_file, buf, sizeof(identity_file));
 118         have_identity = 1;
 119 }
 120
 121 static Key *
 122 load_identity(char *filename)
 123 {
 124         char *pass;
 125         Key *prv;
 126
 127         prv = key_load_private(filename, "", NULL);
 128         if (prv == NULL) {
 129                 if (identity_passphrase)
 130                         pass = xstrdup(identity_passphrase);
 131                 else
 132                         pass = read_passphrase("Enter passphrase: ",
 133                             RP_ALLOW_STDIN);
 134                 prv = key_load_private(filename, pass, NULL);
 135                 memset(pass, 0, strlen(pass));
 136                 xfree(pass);
 137         }
 138         return prv;
 139 }
 140
 141 #define SSH_COM_PUBLIC_BEGIN            "---- BEGIN SSH2 PUBLIC KEY ----"
 142 #define SSH_COM_PUBLIC_END              "---- END SSH2 PUBLIC KEY ----"
 143 #define SSH_COM_PRIVATE_BEGIN           "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----"
 144 #define SSH_COM_PRIVATE_KEY_MAGIC       0x3f6ff9eb
 145
 146 static void
 147 do_convert_to_ssh2(struct passwd *pw)
 148 {
 149         Key *k;
 150         int len;
 151         u_char *blob;
 152         struct stat st;
 153
 154         if (!have_identity)
 155                 ask_filename(pw, "Enter file in which the key is");
 156         if (stat(identity_file, &st) < 0) {
 157                 perror(identity_file);
 158                 exit(1);
 159         }
 160         if ((k = key_load_public(identity_file, NULL)) == NULL) {
 161                 if ((k = load_identity(identity_file)) == NULL) {
 162                         fprintf(stderr, "load failed\n");
 163                         exit(1);
 164                 }
 165         }
 166         key_to_blob(k, &blob, &len);
 167         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_BEGIN);
 168         fprintf(stdout,
 169             "Comment: \"%d-bit %s, converted from OpenSSH by %s@%s\"\n",
 170             key_size(k), key_type(k),
 171             pw->pw_name, hostname);
 172         dump_base64(stdout, blob, len);
 173         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_END);
 174         key_free(k);
 175         xfree(blob);
 176         exit(0);
 177 }
 178
 179 static void
 180 buffer_get_bignum_bits(Buffer *b, BIGNUM *value)
 181 {
 182         int bits = buffer_get_int(b);
 183         int bytes = (bits + 7) / 8;
 184
 185         if (buffer_len(b) < bytes)
 186                 fatal("buffer_get_bignum_bits: input buffer too small: "
 187                     "need %d have %d", bytes, buffer_len(b));
 188         BN_bin2bn((u_char *)buffer_ptr(b), bytes, value);
 189         buffer_consume(b, bytes);
 190 }
 191
 192 static Key *
 193 do_convert_private_ssh2_from_blob(char *blob, int blen)
 194 {
 195         Buffer b;
 196         Key *key = NULL;
 197         char *type, *cipher;
 198         u_char *sig, data[] = "abcde12345";
 199         int magic, rlen, ktype, i1, i2, i3, i4;
 200         u_int slen;
 201         u_long e;
 202
 203         buffer_init(&b);
 204         buffer_append(&b, blob, blen);
 205
 206         magic  = buffer_get_int(&b);
 207         if (magic != SSH_COM_PRIVATE_KEY_MAGIC) {
 208                 error("bad magic 0x%x != 0x%x", magic, SSH_COM_PRIVATE_KEY_MAGIC);
 209                 buffer_free(&b);
 210                 return NULL;
 211         }
 212         i1 = buffer_get_int(&b);
 213         type   = buffer_get_string(&b, NULL);
 214         cipher = buffer_get_string(&b, NULL);
 215         i2 = buffer_get_int(&b);
 216         i3 = buffer_get_int(&b);
 217         i4 = buffer_get_int(&b);
 218         debug("ignore (%d %d %d %d)", i1,i2,i3,i4);
 219         if (strcmp(cipher, "none") != 0) {
 220                 error("unsupported cipher %s", cipher);
 221                 xfree(cipher);
 222                 buffer_free(&b);
 223                 xfree(type);
 224                 return NULL;
 225         }
 226         xfree(cipher);
 227
 228         if (strstr(type, "dsa")) {
 229                 ktype = KEY_DSA;
 230         } else if (strstr(type, "rsa")) {
 231                 ktype = KEY_RSA;
 232         } else {
 233                 xfree(type);
 234                 return NULL;
 235         }
 236         key = key_new_private(ktype);
 237         xfree(type);
 238
 239         switch (key->type) {
 240         case KEY_DSA:
 241                 buffer_get_bignum_bits(&b, key->dsa->p);
 242                 buffer_get_bignum_bits(&b, key->dsa->g);
 243                 buffer_get_bignum_bits(&b, key->dsa->q);
 244                 buffer_get_bignum_bits(&b, key->dsa->pub_key);
 245                 buffer_get_bignum_bits(&b, key->dsa->priv_key);
 246                 break;
 247         case KEY_RSA:
 248                 e  = buffer_get_char(&b);
 249                 debug("e %lx", e);
 250                 if (e < 30) {
 251                         e <<= 8;
 252                         e += buffer_get_char(&b);
 253                         debug("e %lx", e);
 254                         e <<= 8;
 255                         e += buffer_get_char(&b);
 256                         debug("e %lx", e);
 257                 }
 258                 if (!BN_set_word(key->rsa->e, e)) {
 259                         buffer_free(&b);
 260                         key_free(key);
 261                         return NULL;
 262                 }
 263                 buffer_get_bignum_bits(&b, key->rsa->d);
 264                 buffer_get_bignum_bits(&b, key->rsa->n);
 265                 buffer_get_bignum_bits(&b, key->rsa->iqmp);
 266                 buffer_get_bignum_bits(&b, key->rsa->q);
 267                 buffer_get_bignum_bits(&b, key->rsa->p);
 268                 rsa_generate_additional_parameters(key->rsa);
 269                 break;
 270         }
 271         rlen = buffer_len(&b);
 272         if(rlen != 0)
 273                 error("do_convert_private_ssh2_from_blob: "
 274                     "remaining bytes in key blob %d", rlen);
 275         buffer_free(&b);
 276
 277         /* try the key */
 278         key_sign(key, &sig, &slen, data, sizeof(data));
 279         key_verify(key, sig, slen, data, sizeof(data));
 280         xfree(sig);
 281         return key;
 282 }
 283
 284 static void
 285 do_convert_from_ssh2(struct passwd *pw)
 286 {
 287         Key *k;
 288         int blen;
 289         char line[1024], *p;
 290         char blob[8096];
 291         char encoded[8096];
 292         struct stat st;
 293         int escaped = 0, private = 0, ok;
 294         FILE *fp;
 295
 296         if (!have_identity)
 297                 ask_filename(pw, "Enter file in which the key is");
 298         if (stat(identity_file, &st) < 0) {
 299                 perror(identity_file);
 300                 exit(1);
 301         }
 302         fp = fopen(identity_file, "r");
 303         if (fp == NULL) {
 304                 perror(identity_file);
 305                 exit(1);
 306         }
 307         encoded[0] = '\0';
 308         while (fgets(line, sizeof(line), fp)) {
 309                 if (!(p = strchr(line, '\n'))) {
 310                         fprintf(stderr, "input line too long.\n");
 311                         exit(1);
 312                 }
 313                 if (p > line && p[-1] == '\\')
 314                         escaped++;
 315                 if (strncmp(line, "----", 4) == 0 ||
 316                     strstr(line, ": ") != NULL) {
 317                         if (strstr(line, SSH_COM_PRIVATE_BEGIN) != NULL)
 318                                 private = 1;
 319                         if (strstr(line, " END ") != NULL) {
 320                                 break;
 321                         }
 322                         /* fprintf(stderr, "ignore: %s", line); */
 323                         continue;
 324                 }
 325                 if (escaped) {
 326                         escaped--;
 327                         /* fprintf(stderr, "escaped: %s", line); */
 328                         continue;
 329                 }
 330                 *p = '\0';
 331                 strlcat(encoded, line, sizeof(encoded));
 332         }
 333         blen = uudecode(encoded, (u_char *)blob, sizeof(blob));
 334         if (blen < 0) {
 335                 fprintf(stderr, "uudecode failed.\n");
 336                 exit(1);
 337         }
 338         k = private ?
 339             do_convert_private_ssh2_from_blob(blob, blen) :
 340             key_from_blob(blob, blen);
 341         if (k == NULL) {
 342                 fprintf(stderr, "decode blob failed.\n");
 343                 exit(1);
 344         }
 345         ok = private ?
 346             (k->type == KEY_DSA ?
 347                  PEM_write_DSAPrivateKey(stdout, k->dsa, NULL, NULL, 0, NULL, NULL) :
 348                  PEM_write_RSAPrivateKey(stdout, k->rsa, NULL, NULL, 0, NULL, NULL)) :
 349             key_write(k, stdout);
 350         if (!ok) {
 351                 fprintf(stderr, "key write failed");
 352                 exit(1);
 353         }
 354         key_free(k);
 355         fprintf(stdout, "\n");
 356         fclose(fp);
 357         exit(0);
 358 }
 359
 360 static void
 361 do_print_public(struct passwd *pw)
 362 {
 363         Key *prv;
 364         struct stat st;
 365
 366         if (!have_identity)
 367                 ask_filename(pw, "Enter file in which the key is");
 368         if (stat(identity_file, &st) < 0) {
 369                 perror(identity_file);
 370                 exit(1);
 371         }
 372         prv = load_identity(identity_file);
 373         if (prv == NULL) {
 374                 fprintf(stderr, "load failed\n");
 375                 exit(1);
 376         }
 377         if (!key_write(prv, stdout))
 378                 fprintf(stderr, "key_write failed");
 379         key_free(prv);
 380         fprintf(stdout, "\n");
 381         exit(0);
 382 }
 383
 384 #ifdef SMARTCARD
 385 #define NUM_RSA_KEY_ELEMENTS 5+1
 386 #define COPY_RSA_KEY(x, i) \
 387         do { \
 388                 len = BN_num_bytes(prv->rsa->x); \
 389                 elements[i] = xmalloc(len); \
 390                 debug("#bytes %d", len); \
 391                 if (BN_bn2bin(prv->rsa->x, elements[i]) < 0) \
 392                         goto done; \
 393         } while(0)
 394
 395 static int
 396 get_AUT0(char *aut0)
 397 {
 398         EVP_MD *evp_md = EVP_sha1();
 399         EVP_MD_CTX md;
 400         char *pass;
 401
 402         pass = read_passphrase("Enter passphrase for smartcard: ", RP_ALLOW_STDIN);
 403         if (pass == NULL)
 404                 return -1;
 405         EVP_DigestInit(&md, evp_md);
 406         EVP_DigestUpdate(&md, pass, strlen(pass));
 407         EVP_DigestFinal(&md, aut0, NULL);
 408         memset(pass, 0, strlen(pass));
 409         xfree(pass);
 410         return 0;
 411 }
 412
 413 static void
 414 do_upload(struct passwd *pw, const char *sc_reader_id)
 415 {
 416         Key *prv = NULL;
 417         struct stat st;
 418         u_char *elements[NUM_RSA_KEY_ELEMENTS];
 419         u_char key_fid[2];
 420         u_char DEFAUT0[] = {0xad, 0x9f, 0x61, 0xfe, 0xfa, 0x20, 0xce, 0x63};
 421         u_char AUT0[EVP_MAX_MD_SIZE];
 422         int len, status = 1, i, fd = -1, ret;
 423         int sw = 0, cla = 0x00;
 424
 425         for (i = 0; i < NUM_RSA_KEY_ELEMENTS; i++)
 426                 elements[i] = NULL;
 427         if (!have_identity)
 428                 ask_filename(pw, "Enter file in which the key is");
 429         if (stat(identity_file, &st) < 0) {
 430                 perror(identity_file);
 431                 goto done;
 432         }
 433         prv = load_identity(identity_file);
 434         if (prv == NULL) {
 435                 error("load failed");
 436                 goto done;
 437         }
 438         COPY_RSA_KEY(q, 0);
 439         COPY_RSA_KEY(p, 1);
 440         COPY_RSA_KEY(iqmp, 2);
 441         COPY_RSA_KEY(dmq1, 3);
 442         COPY_RSA_KEY(dmp1, 4);
 443         COPY_RSA_KEY(n, 5);
 444         len = BN_num_bytes(prv->rsa->n);
 445         fd = sectok_friendly_open(sc_reader_id, STONOWAIT, &sw);
 446         if (fd < 0) {
 447                 error("sectok_open failed: %s", sectok_get_sw(sw));
 448                 goto done;
 449         }
 450         if (! sectok_cardpresent(fd)) {
 451                 error("smartcard in reader %s not present",
 452                     sc_reader_id);
 453                 goto done;
 454         }
 455         ret = sectok_reset(fd, 0, NULL, &sw);
 456         if (ret <= 0) {
 457                 error("sectok_reset failed: %s", sectok_get_sw(sw));
 458                 goto done;
 459         }
 460         if ((cla = cyberflex_inq_class(fd)) < 0) {
 461                 error("cyberflex_inq_class failed");
 462                 goto done;
 463         }
 464         memcpy(AUT0, DEFAUT0, sizeof(DEFAUT0));
 465         if (cyberflex_verify_AUT0(fd, cla, AUT0, sizeof(DEFAUT0)) < 0) {
 466                 if (get_AUT0(AUT0) < 0 ||
 467                     cyberflex_verify_AUT0(fd, cla, AUT0, sizeof(DEFAUT0)) < 0) {
 468                         error("cyberflex_verify_AUT0 failed");
 469                         goto done;
 470                 }
 471         }
 472         key_fid[0] = 0x00;
 473         key_fid[1] = 0x12;
 474         if (cyberflex_load_rsa_priv(fd, cla, key_fid, 5, 8*len, elements,
 475             &sw) < 0) {
 476                 error("cyberflex_load_rsa_priv failed: %s", sectok_get_sw(sw));
 477                 goto done;
 478         }
 479         if (!sectok_swOK(sw))
 480                 goto done;
 481         log("cyberflex_load_rsa_priv done");
 482         key_fid[0] = 0x73;
 483         key_fid[1] = 0x68;
 484         if (cyberflex_load_rsa_pub(fd, cla, key_fid, len, elements[5],
 485             &sw) < 0) {
 486                 error("cyberflex_load_rsa_pub failed: %s", sectok_get_sw(sw));
 487                 goto done;
 488         }
 489         if (!sectok_swOK(sw))
 490                 goto done;
 491         log("cyberflex_load_rsa_pub done");
 492         status = 0;
 493         log("loading key done");
 494 done:
 495         if (prv)
 496                 key_free(prv);
 497         for (i = 0; i < NUM_RSA_KEY_ELEMENTS; i++)
 498                 if (elements[i])
 499                         xfree(elements[i]);
 500         if (fd != -1)
 501                 sectok_close(fd);
 502         exit(status);
 503 }
 504
 505 static void
 506 do_download(struct passwd *pw, const char *sc_reader_id)
 507 {
 508         Key *pub = NULL;
 509
 510         pub = sc_get_key(sc_reader_id);
 511         if (pub == NULL)
 512                 fatal("cannot read public key from smartcard");
 513         key_write(pub, stdout);
 514         key_free(pub);
 515         fprintf(stdout, "\n");
 516         exit(0);
 517 }
 518 #endif
 519
 520 static void
 521 do_fingerprint(struct passwd *pw)
 522 {
 523         FILE *f;
 524         Key *public;
 525         char *comment = NULL, *cp, *ep, line[16*1024], *fp;
 526         int i, skip = 0, num = 1, invalid = 1, rep, fptype;
 527         struct stat st;
 528
 529         fptype = print_bubblebabble ? SSH_FP_SHA1 : SSH_FP_MD5;
 530         rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_HEX;
 531
 532         if (!have_identity)
 533                 ask_filename(pw, "Enter file in which the key is");
 534         if (stat(identity_file, &st) < 0) {
 535                 perror(identity_file);
 536                 exit(1);
 537         }
 538         public = key_load_public(identity_file, &comment);
 539         if (public != NULL) {
 540                 fp = key_fingerprint(public, fptype, rep);
 541                 printf("%d %s %s\n", key_size(public), fp, comment);
 542                 key_free(public);
 543                 xfree(comment);
 544                 xfree(fp);
 545                 exit(0);
 546         }
 547         if (comment)
 548                 xfree(comment);
 549
 550         f = fopen(identity_file, "r");
 551         if (f != NULL) {
 552                 while (fgets(line, sizeof(line), f)) {
 553                         i = strlen(line) - 1;
 554                         if (line[i] != '\n') {
 555                                 error("line %d too long: %.40s...", num, line);
 556                                 skip = 1;
 557                                 continue;
 558                         }
 559                         num++;
 560                         if (skip) {
 561                                 skip = 0;
 562                                 continue;
 563                         }
 564                         line[i] = '\0';
 565
 566                         /* Skip leading whitespace, empty and comment lines. */
 567                         for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
 568                                 ;
 569                         if (!*cp || *cp == '\n' || *cp == '#')
 570                                 continue ;
 571                         i = strtol(cp, &ep, 10);
 572                         if (i == 0 || ep == NULL || (*ep != ' ' && *ep != '\t')) {
 573                                 int quoted = 0;
 574                                 comment = cp;
 575                                 for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
 576                                         if (*cp == '\\' && cp[1] == '"')
 577                                                 cp++;   /* Skip both */
 578                                         else if (*cp == '"')
 579                                                 quoted = !quoted;
 580                                 }
 581                                 if (!*cp)
 582                                         continue;
 583                                 *cp++ = '\0';
 584                         }
 585                         ep = cp;
 586                         public = key_new(KEY_RSA1);
 587                         if (key_read(public, &cp) != 1) {
 588                                 cp = ep;
 589                                 key_free(public);
 590                                 public = key_new(KEY_UNSPEC);
 591                                 if (key_read(public, &cp) != 1) {
 592                                         key_free(public);
 593                                         continue;
 594                                 }
 595                         }
 596                         comment = *cp ? cp : comment;
 597                         fp = key_fingerprint(public, fptype, rep);
 598                         printf("%d %s %s\n", key_size(public), fp,
 599                             comment ? comment : "no comment");
 600                         xfree(fp);
 601                         key_free(public);
 602                         invalid = 0;
 603                 }
 604                 fclose(f);
 605         }
 606         if (invalid) {
 607                 printf("%s is not a valid key file.\n", identity_file);
 608                 exit(1);
 609         }
 610         exit(0);
 611 }
 612
 613 /*
 614  * Perform changing a passphrase.  The argument is the passwd structure
 615  * for the current user.
 616  */
 617 static void
 618 do_change_passphrase(struct passwd *pw)
 619 {
 620         char *comment;
 621         char *old_passphrase, *passphrase1, *passphrase2;
 622         struct stat st;
 623         Key *private;
 624
 625         if (!have_identity)
 626                 ask_filename(pw, "Enter file in which the key is");
 627         if (stat(identity_file, &st) < 0) {
 628                 perror(identity_file);
 629                 exit(1);
 630         }
 631         /* Try to load the file with empty passphrase. */
 632         private = key_load_private(identity_file, "", &comment);
 633         if (private == NULL) {
 634                 if (identity_passphrase)
 635                         old_passphrase = xstrdup(identity_passphrase);
 636                 else
 637                         old_passphrase =
 638                             read_passphrase("Enter old passphrase: ",
 639                             RP_ALLOW_STDIN);
 640                 private = key_load_private(identity_file, old_passphrase,
 641                     &comment);
 642                 memset(old_passphrase, 0, strlen(old_passphrase));
 643                 xfree(old_passphrase);
 644                 if (private == NULL) {
 645                         printf("Bad passphrase.\n");
 646                         exit(1);
 647                 }
 648         }
 649         printf("Key has comment '%s'\n", comment);
 650
 651         /* Ask the new passphrase (twice). */
 652         if (identity_new_passphrase) {
 653                 passphrase1 = xstrdup(identity_new_passphrase);
 654                 passphrase2 = NULL;
 655         } else {
 656                 passphrase1 =
 657                         read_passphrase("Enter new passphrase (empty for no "
 658                             "passphrase): ", RP_ALLOW_STDIN);
 659                 passphrase2 = read_passphrase("Enter same passphrase again: ",
 660                      RP_ALLOW_STDIN);
 661
 662                 /* Verify that they are the same. */
 663                 if (strcmp(passphrase1, passphrase2) != 0) {
 664                         memset(passphrase1, 0, strlen(passphrase1));
 665                         memset(passphrase2, 0, strlen(passphrase2));
 666                         xfree(passphrase1);
 667                         xfree(passphrase2);
 668                         printf("Pass phrases do not match.  Try again.\n");
 669                         exit(1);
 670                 }
 671                 /* Destroy the other copy. */
 672                 memset(passphrase2, 0, strlen(passphrase2));
 673                 xfree(passphrase2);
 674         }
 675
 676         /* Save the file using the new passphrase. */
 677         if (!key_save_private(private, identity_file, passphrase1, comment)) {
 678                 printf("Saving the key failed: %s.\n", identity_file);
 679                 memset(passphrase1, 0, strlen(passphrase1));
 680                 xfree(passphrase1);
 681                 key_free(private);
 682                 xfree(comment);
 683                 exit(1);
 684         }
 685         /* Destroy the passphrase and the copy of the key in memory. */
 686         memset(passphrase1, 0, strlen(passphrase1));
 687         xfree(passphrase1);
 688         key_free(private);               /* Destroys contents */
 689         xfree(comment);
 690
 691         printf("Your identification has been saved with the new passphrase.\n");
 692         exit(0);
 693 }
 694
 695 /*
 696  * Change the comment of a private key file.
 697  */
 698 static void
 699 do_change_comment(struct passwd *pw)
 700 {
 701         char new_comment[1024], *comment, *passphrase;
 702         Key *private;
 703         Key *public;
 704         struct stat st;
 705         FILE *f;
 706         int fd;
 707
 708         if (!have_identity)
 709                 ask_filename(pw, "Enter file in which the key is");
 710         if (stat(identity_file, &st) < 0) {
 711                 perror(identity_file);
 712                 exit(1);
 713         }
 714         private = key_load_private(identity_file, "", &comment);
 715         if (private == NULL) {
 716                 if (identity_passphrase)
 717                         passphrase = xstrdup(identity_passphrase);
 718                 else if (identity_new_passphrase)
 719                         passphrase = xstrdup(identity_new_passphrase);
 720                 else
 721                         passphrase = read_passphrase("Enter passphrase: ",
 722                             RP_ALLOW_STDIN);
 723                 /* Try to load using the passphrase. */
 724                 private = key_load_private(identity_file, passphrase, &comment);
 725                 if (private == NULL) {
 726                         memset(passphrase, 0, strlen(passphrase));
 727                         xfree(passphrase);
 728                         printf("Bad passphrase.\n");
 729                         exit(1);
 730                 }
 731         } else {
 732                 passphrase = xstrdup("");
 733         }
 734         if (private->type != KEY_RSA1) {
 735                 fprintf(stderr, "Comments are only supported for RSA1 keys.\n");
 736                 key_free(private);
 737                 exit(1);
 738         }
 739         printf("Key now has comment '%s'\n", comment);
 740
 741         if (identity_comment) {
 742                 strlcpy(new_comment, identity_comment, sizeof(new_comment));
 743         } else {
 744                 printf("Enter new comment: ");
 745                 fflush(stdout);
 746                 if (!fgets(new_comment, sizeof(new_comment), stdin)) {
 747                         memset(passphrase, 0, strlen(passphrase));
 748                         key_free(private);
 749                         exit(1);
 750                 }
 751                 if (strchr(new_comment, '\n'))
 752                         *strchr(new_comment, '\n') = 0;
 753         }
 754
 755         /* Save the file using the new passphrase. */
 756         if (!key_save_private(private, identity_file, passphrase, new_comment)) {
 757                 printf("Saving the key failed: %s.\n", identity_file);
 758                 memset(passphrase, 0, strlen(passphrase));
 759                 xfree(passphrase);
 760                 key_free(private);
 761                 xfree(comment);
 762                 exit(1);
 763         }
 764         memset(passphrase, 0, strlen(passphrase));
 765         xfree(passphrase);
 766         public = key_from_private(private);
 767         key_free(private);
 768
 769         strlcat(identity_file, ".pub", sizeof(identity_file));
 770         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 771         if (fd == -1) {
 772                 printf("Could not save your public key in %s\n", identity_file);
 773                 exit(1);
 774         }
 775         f = fdopen(fd, "w");
 776         if (f == NULL) {
 777                 printf("fdopen %s failed", identity_file);
 778                 exit(1);
 779         }
 780         if (!key_write(public, f))
 781                 fprintf(stderr, "write key failed");
 782         key_free(public);
 783         fprintf(f, " %s\n", new_comment);
 784         fclose(f);
 785
 786         xfree(comment);
 787
 788         printf("The comment in your key file has been changed.\n");
 789         exit(0);
 790 }
 791
 792 static void
 793 usage(void)
 794 {
 795         fprintf(stderr, "Usage: %s [options]\n", __progname);
 796         fprintf(stderr, "Options:\n");
 797         fprintf(stderr, "  -b bits     Number of bits in the key to create.\n");
 798         fprintf(stderr, "  -c          Change comment in private and public key files.\n");
 799         fprintf(stderr, "  -e          Convert OpenSSH to IETF SECSH key file.\n");
 800         fprintf(stderr, "  -f filename Filename of the key file.\n");
 801         fprintf(stderr, "  -i          Convert IETF SECSH to OpenSSH key file.\n");
 802         fprintf(stderr, "  -l          Show fingerprint of key file.\n");
 803         fprintf(stderr, "  -p          Change passphrase of private key file.\n");
 804         fprintf(stderr, "  -q          Quiet.\n");
 805         fprintf(stderr, "  -y          Read private key file and print public key.\n");
 806         fprintf(stderr, "  -t type     Specify type of key to create.\n");
 807         fprintf(stderr, "  -B          Show bubblebabble digest of key file.\n");
 808         fprintf(stderr, "  -C comment  Provide new comment.\n");
 809         fprintf(stderr, "  -N phrase   Provide new passphrase.\n");
 810         fprintf(stderr, "  -P phrase   Provide old passphrase.\n");
 811 #ifdef SMARTCARD
 812         fprintf(stderr, "  -D reader   Download public key from smartcard.\n");
 813         fprintf(stderr, "  -U reader   Upload private key to smartcard.\n");
 814 #endif /* SMARTCARD */
 815
 816         exit(1);
 817 }
 818
 819 /*
 820  * Main program for key management.
 821  */
 822 int
 823 main(int ac, char **av)
 824 {
 825         char dotsshdir[16 * 1024], comment[1024], *passphrase1, *passphrase2;
 826         char *reader_id = NULL;
 827         Key *private, *public;
 828         struct passwd *pw;
 829         struct stat st;
 830         int opt, type, fd, download = 0;
 831         FILE *f;
 832
 833         extern int optind;
 834         extern char *optarg;
 835
 836         __progname = get_progname(av[0]);
 837         init_rng();
 838         seed_rng();
 839
 840         SSLeay_add_all_algorithms();
 841
 842         /* we need this for the home * directory.  */
 843         pw = getpwuid(getuid());
 844         if (!pw) {
 845                 printf("You don't exist, go away!\n");
 846                 exit(1);
 847         }
 848         if (gethostname(hostname, sizeof(hostname)) < 0) {
 849                 perror("gethostname");
 850                 exit(1);
 851         }
 852
 853         while ((opt = getopt(ac, av, "deiqpclBRxXyb:f:t:U:D:P:N:C:")) != -1) {
 854                 switch (opt) {
 855                 case 'b':
 856                         bits = atoi(optarg);
 857                         if (bits < 512 || bits > 32768) {
 858                                 printf("Bits has bad value.\n");
 859                                 exit(1);
 860                         }
 861                         break;
 862                 case 'l':
 863                         print_fingerprint = 1;
 864                         break;
 865                 case 'B':
 866                         print_bubblebabble = 1;
 867                         break;
 868                 case 'p':
 869                         change_passphrase = 1;
 870                         break;
 871                 case 'c':
 872                         change_comment = 1;
 873                         break;
 874                 case 'f':
 875                         strlcpy(identity_file, optarg, sizeof(identity_file));
 876                         have_identity = 1;
 877                         break;
 878                 case 'P':
 879                         identity_passphrase = optarg;
 880                         break;
 881                 case 'N':
 882                         identity_new_passphrase = optarg;
 883                         break;
 884                 case 'C':
 885                         identity_comment = optarg;
 886                         break;
 887                 case 'q':
 888                         quiet = 1;
 889                         break;
 890                 case 'R':
 891                         /* unused */
 892                         exit(0);
 893                         break;
 894                 case 'e':
 895                 case 'x':
 896                         /* export key */
 897                         convert_to_ssh2 = 1;
 898                         break;
 899                 case 'i':
 900                 case 'X':
 901                         /* import key */
 902                         convert_from_ssh2 = 1;
 903                         break;
 904                 case 'y':
 905                         print_public = 1;
 906                         break;
 907                 case 'd':
 908                         key_type_name = "dsa";
 909                         break;
 910                 case 't':
 911                         key_type_name = optarg;
 912                         break;
 913                 case 'D':
 914                         download = 1;
 915                 case 'U':
 916                         reader_id = optarg;
 917                         break;
 918                 case '?':
 919                 default:
 920                         usage();
 921                 }
 922         }
 923         if (optind < ac) {
 924                 printf("Too many arguments.\n");
 925                 usage();
 926         }
 927         if (change_passphrase && change_comment) {
 928                 printf("Can only have one of -p and -c.\n");
 929                 usage();
 930         }
 931         if (print_fingerprint || print_bubblebabble)
 932                 do_fingerprint(pw);
 933         if (change_passphrase)
 934                 do_change_passphrase(pw);
 935         if (change_comment)
 936                 do_change_comment(pw);
 937         if (convert_to_ssh2)
 938                 do_convert_to_ssh2(pw);
 939         if (convert_from_ssh2)
 940                 do_convert_from_ssh2(pw);
 941         if (print_public)
 942                 do_print_public(pw);
 943         if (reader_id != NULL) {
 944 #ifdef SMARTCARD
 945                 if (download)
 946                         do_download(pw, reader_id);
 947                 else
 948                         do_upload(pw, reader_id);
 949 #else
 950                 fatal("no support for smartcards.");
 951 #endif
 952         }
 953
 954         arc4random_stir();
 955
 956         type = key_type_from_name(key_type_name);
 957         if (type == KEY_UNSPEC) {
 958                 fprintf(stderr, "unknown key type %s\n", key_type_name);
 959                 exit(1);
 960         }
 961         if (!quiet)
 962                 printf("Generating public/private %s key pair.\n", key_type_name);
 963         private = key_generate(type, bits);
 964         if (private == NULL) {
 965                 fprintf(stderr, "key_generate failed");
 966                 exit(1);
 967         }
 968         public  = key_from_private(private);
 969
 970         if (!have_identity)
 971                 ask_filename(pw, "Enter file in which to save the key");
 972
 973         /* Create ~/.ssh directory if it doesn\'t already exist. */
 974         snprintf(dotsshdir, sizeof dotsshdir, "%s/%s", pw->pw_dir, _PATH_SSH_USER_DIR);
 975         if (strstr(identity_file, dotsshdir) != NULL &&
 976             stat(dotsshdir, &st) < 0) {
 977                 if (mkdir(dotsshdir, 0700) < 0)
 978                         error("Could not create directory '%s'.", dotsshdir);
 979                 else if (!quiet)
 980                         printf("Created directory '%s'.\n", dotsshdir);
 981         }
 982         /* If the file already exists, ask the user to confirm. */
 983         if (stat(identity_file, &st) >= 0) {
 984                 char yesno[3];
 985                 printf("%s already exists.\n", identity_file);
 986                 printf("Overwrite (y/n)? ");
 987                 fflush(stdout);
 988                 if (fgets(yesno, sizeof(yesno), stdin) == NULL)
 989                         exit(1);
 990                 if (yesno[0] != 'y' && yesno[0] != 'Y')
 991                         exit(1);
 992         }
 993         /* Ask for a passphrase (twice). */
 994         if (identity_passphrase)
 995                 passphrase1 = xstrdup(identity_passphrase);
 996         else if (identity_new_passphrase)
 997                 passphrase1 = xstrdup(identity_new_passphrase);
 998         else {
 999 passphrase_again:
1000                 passphrase1 =
1001                         read_passphrase("Enter passphrase (empty for no "
1002                             "passphrase): ", RP_ALLOW_STDIN);
1003                 passphrase2 = read_passphrase("Enter same passphrase again: ",
1004                     RP_ALLOW_STDIN);
1005                 if (strcmp(passphrase1, passphrase2) != 0) {
1006                         /*
1007                          * The passphrases do not match.  Clear them and
1008                          * retry.
1009                          */
1010                         memset(passphrase1, 0, strlen(passphrase1));
1011                         memset(passphrase2, 0, strlen(passphrase2));
1012                         xfree(passphrase1);
1013                         xfree(passphrase2);
1014                         printf("Passphrases do not match.  Try again.\n");
1015                         goto passphrase_again;
1016                 }
1017                 /* Clear the other copy of the passphrase. */
1018                 memset(passphrase2, 0, strlen(passphrase2));
1019                 xfree(passphrase2);
1020         }
1021
1022         if (identity_comment) {
1023                 strlcpy(comment, identity_comment, sizeof(comment));
1024         } else {
1025                 /* Create default commend field for the passphrase. */
1026                 snprintf(comment, sizeof comment, "%s@%s", pw->pw_name, hostname);
1027         }
1028
1029         /* Save the key with the given passphrase and comment. */
1030         if (!key_save_private(private, identity_file, passphrase1, comment)) {
1031                 printf("Saving the key failed: %s.\n", identity_file);
1032                 memset(passphrase1, 0, strlen(passphrase1));
1033                 xfree(passphrase1);
1034                 exit(1);
1035         }
1036         /* Clear the passphrase. */
1037         memset(passphrase1, 0, strlen(passphrase1));
1038         xfree(passphrase1);
1039
1040         /* Clear the private key and the random number generator. */
1041         key_free(private);
1042         arc4random_stir();
1043
1044         if (!quiet)
1045                 printf("Your identification has been saved in %s.\n", identity_file);
1046
1047         strlcat(identity_file, ".pub", sizeof(identity_file));
1048         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
1049         if (fd == -1) {
1050                 printf("Could not save your public key in %s\n", identity_file);
1051                 exit(1);
1052         }
1053         f = fdopen(fd, "w");
1054         if (f == NULL) {
1055                 printf("fdopen %s failed", identity_file);
1056                 exit(1);
1057         }
1058         if (!key_write(public, f))
1059                 fprintf(stderr, "write key failed");
1060         fprintf(f, " %s\n", comment);
1061         fclose(f);
1062
1063         if (!quiet) {
1064                 char *fp = key_fingerprint(public, SSH_FP_MD5, SSH_FP_HEX);
1065                 printf("Your public key has been saved in %s.\n",
1066                     identity_file);
1067                 printf("The key fingerprint is:\n");
1068                 printf("%s %s\n", fp, comment);
1069                 xfree(fp);
1070         }
1071
1072         key_free(public);
1073         exit(0);
1074 }