crypto/openssh/ssh-keygen.c

   1 /* $OpenBSD: ssh-keygen.c,v 1.216 2012/07/06 06:38:03 jmc Exp $ */
   2 /*
   3  * Author: Tatu Ylonen <ylo@cs.hut.fi>
   4  * Copyright (c) 1994 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
   5  *                    All rights reserved
   6  * Identity and host key generation and maintenance.
   7  *
   8  * As far as I am concerned, the code I have written for this software
   9  * can be used freely for any purpose.  Any derived versions of this
  10  * software must be clearly marked as such, and if the derived work is
  11  * incompatible with the protocol description in the RFC file, it must be
  12  * called by a name other than "ssh" or "Secure Shell".
  13  */
  14
  15 #include "includes.h"
  16
  17 #include <sys/types.h>
  18 #include <sys/socket.h>
  19 #include <sys/stat.h>
  20 #include <sys/param.h>
  21
  22 #include <openssl/evp.h>
  23 #include <openssl/pem.h>
  24 #include "openbsd-compat/openssl-compat.h"
  25
  26 #include <errno.h>
  27 #include <fcntl.h>
  28 #include <netdb.h>
  29 #ifdef HAVE_PATHS_H
  30 # include <paths.h>
  31 #endif
  32 #include <pwd.h>
  33 #include <stdarg.h>
  34 #include <stdio.h>
  35 #include <stdlib.h>
  36 #include <string.h>
  37 #include <unistd.h>
  38
  39 #include "xmalloc.h"
  40 #include "key.h"
  41 #include "rsa.h"
  42 #include "authfile.h"
  43 #include "uuencode.h"
  44 #include "buffer.h"
  45 #include "pathnames.h"
  46 #include "log.h"
  47 #include "misc.h"
  48 #include "match.h"
  49 #include "hostfile.h"
  50 #include "dns.h"
  51 #include "ssh2.h"
  52 #include "ssh-pkcs11.h"
  53
  54 /* Number of bits in the RSA/DSA key.  This value can be set on the command line. */
  55 #define DEFAULT_BITS            2048
  56 #define DEFAULT_BITS_DSA        1024
  57 #define DEFAULT_BITS_ECDSA      256
  58 u_int32_t bits = 0;
  59
  60 /*
  61  * Flag indicating that we just want to change the passphrase.  This can be
  62  * set on the command line.
  63  */
  64 int change_passphrase = 0;
  65
  66 /*
  67  * Flag indicating that we just want to change the comment.  This can be set
  68  * on the command line.
  69  */
  70 int change_comment = 0;
  71
  72 int quiet = 0;
  73
  74 int log_level = SYSLOG_LEVEL_INFO;
  75
  76 /* Flag indicating that we want to hash a known_hosts file */
  77 int hash_hosts = 0;
  78 /* Flag indicating that we want lookup a host in known_hosts file */
  79 int find_host = 0;
  80 /* Flag indicating that we want to delete a host from a known_hosts file */
  81 int delete_host = 0;
  82
  83 /* Flag indicating that we want to show the contents of a certificate */
  84 int show_cert = 0;
  85
  86 /* Flag indicating that we just want to see the key fingerprint */
  87 int print_fingerprint = 0;
  88 int print_bubblebabble = 0;
  89
  90 /* The identity file name, given on the command line or entered by the user. */
  91 char identity_file[1024];
  92 int have_identity = 0;
  93
  94 /* This is set to the passphrase if given on the command line. */
  95 char *identity_passphrase = NULL;
  96
  97 /* This is set to the new passphrase if given on the command line. */
  98 char *identity_new_passphrase = NULL;
  99
 100 /* This is set to the new comment if given on the command line. */
 101 char *identity_comment = NULL;
 102
 103 /* Path to CA key when certifying keys. */
 104 char *ca_key_path = NULL;
 105
 106 /* Certificate serial number */
 107 long long cert_serial = 0;
 108
 109 /* Key type when certifying */
 110 u_int cert_key_type = SSH2_CERT_TYPE_USER;
 111
 112 /* "key ID" of signed key */
 113 char *cert_key_id = NULL;
 114
 115 /* Comma-separated list of principal names for certifying keys */
 116 char *cert_principals = NULL;
 117
 118 /* Validity period for certificates */
 119 u_int64_t cert_valid_from = 0;
 120 u_int64_t cert_valid_to = ~0ULL;
 121
 122 /* Certificate options */
 123 #define CERTOPT_X_FWD   (1)
 124 #define CERTOPT_AGENT_FWD       (1<<1)
 125 #define CERTOPT_PORT_FWD        (1<<2)
 126 #define CERTOPT_PTY             (1<<3)
 127 #define CERTOPT_USER_RC (1<<4)
 128 #define CERTOPT_DEFAULT (CERTOPT_X_FWD|CERTOPT_AGENT_FWD| \
 129                          CERTOPT_PORT_FWD|CERTOPT_PTY|CERTOPT_USER_RC)
 130 u_int32_t certflags_flags = CERTOPT_DEFAULT;
 131 char *certflags_command = NULL;
 132 char *certflags_src_addr = NULL;
 133
 134 /* Conversion to/from various formats */
 135 int convert_to = 0;
 136 int convert_from = 0;
 137 enum {
 138         FMT_RFC4716,
 139         FMT_PKCS8,
 140         FMT_PEM
 141 } convert_format = FMT_RFC4716;
 142 int print_public = 0;
 143 int print_generic = 0;
 144
 145 char *key_type_name = NULL;
 146
 147 /* Load key from this PKCS#11 provider */
 148 char *pkcs11provider = NULL;
 149
 150 /* argv0 */
 151 extern char *__progname;
 152
 153 char hostname[MAXHOSTNAMELEN];
 154
 155 /* moduli.c */
 156 int gen_candidates(FILE *, u_int32_t, u_int32_t, BIGNUM *);
 157 int prime_test(FILE *, FILE *, u_int32_t, u_int32_t, char *, unsigned long,
 158     unsigned long);
 159
 160 static void
 161 type_bits_valid(int type, u_int32_t *bitsp)
 162 {
 163         u_int maxbits;
 164
 165         if (type == KEY_UNSPEC) {
 166                 fprintf(stderr, "unknown key type %s\n", key_type_name);
 167                 exit(1);
 168         }
 169         if (*bitsp == 0) {
 170                 if (type == KEY_DSA)
 171                         *bitsp = DEFAULT_BITS_DSA;
 172                 else if (type == KEY_ECDSA)
 173                         *bitsp = DEFAULT_BITS_ECDSA;
 174                 else
 175                         *bitsp = DEFAULT_BITS;
 176         }
 177         maxbits = (type == KEY_DSA) ?
 178             OPENSSL_DSA_MAX_MODULUS_BITS : OPENSSL_RSA_MAX_MODULUS_BITS;
 179         if (*bitsp > maxbits) {
 180                 fprintf(stderr, "key bits exceeds maximum %d\n", maxbits);
 181                 exit(1);
 182         }
 183         if (type == KEY_DSA && *bitsp != 1024)
 184                 fatal("DSA keys must be 1024 bits");
 185         else if (type != KEY_ECDSA && *bitsp < 768)
 186                 fatal("Key must at least be 768 bits");
 187         else if (type == KEY_ECDSA && key_ecdsa_bits_to_nid(*bitsp) == -1)
 188                 fatal("Invalid ECDSA key length - valid lengths are "
 189                     "256, 384 or 521 bits");
 190 }
 191
 192 static void
 193 ask_filename(struct passwd *pw, const char *prompt)
 194 {
 195         char buf[1024];
 196         char *name = NULL;
 197
 198         if (key_type_name == NULL)
 199                 name = _PATH_SSH_CLIENT_ID_RSA;
 200         else {
 201                 switch (key_type_from_name(key_type_name)) {
 202                 case KEY_RSA1:
 203                         name = _PATH_SSH_CLIENT_IDENTITY;
 204                         break;
 205                 case KEY_DSA_CERT:
 206                 case KEY_DSA_CERT_V00:
 207                 case KEY_DSA:
 208                         name = _PATH_SSH_CLIENT_ID_DSA;
 209                         break;
 210 #ifdef OPENSSL_HAS_ECC
 211                 case KEY_ECDSA_CERT:
 212                 case KEY_ECDSA:
 213                         name = _PATH_SSH_CLIENT_ID_ECDSA;
 214                         break;
 215 #endif
 216                 case KEY_RSA_CERT:
 217                 case KEY_RSA_CERT_V00:
 218                 case KEY_RSA:
 219                         name = _PATH_SSH_CLIENT_ID_RSA;
 220                         break;
 221                 default:
 222                         fprintf(stderr, "bad key type\n");
 223                         exit(1);
 224                         break;
 225                 }
 226         }
 227         snprintf(identity_file, sizeof(identity_file), "%s/%s", pw->pw_dir, name);
 228         fprintf(stderr, "%s (%s): ", prompt, identity_file);
 229         if (fgets(buf, sizeof(buf), stdin) == NULL)
 230                 exit(1);
 231         buf[strcspn(buf, "\n")] = '\0';
 232         if (strcmp(buf, "") != 0)
 233                 strlcpy(identity_file, buf, sizeof(identity_file));
 234         have_identity = 1;
 235 }
 236
 237 static Key *
 238 load_identity(char *filename)
 239 {
 240         char *pass;
 241         Key *prv;
 242
 243         prv = key_load_private(filename, "", NULL);
 244         if (prv == NULL) {
 245                 if (identity_passphrase)
 246                         pass = xstrdup(identity_passphrase);
 247                 else
 248                         pass = read_passphrase("Enter passphrase: ",
 249                             RP_ALLOW_STDIN);
 250                 prv = key_load_private(filename, pass, NULL);
 251                 memset(pass, 0, strlen(pass));
 252                 xfree(pass);
 253         }
 254         return prv;
 255 }
 256
 257 #define SSH_COM_PUBLIC_BEGIN            "---- BEGIN SSH2 PUBLIC KEY ----"
 258 #define SSH_COM_PUBLIC_END              "---- END SSH2 PUBLIC KEY ----"
 259 #define SSH_COM_PRIVATE_BEGIN           "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----"
 260 #define SSH_COM_PRIVATE_KEY_MAGIC       0x3f6ff9eb
 261
 262 static void
 263 do_convert_to_ssh2(struct passwd *pw, Key *k)
 264 {
 265         u_int len;
 266         u_char *blob;
 267         char comment[61];
 268
 269         if (k->type == KEY_RSA1) {
 270                 fprintf(stderr, "version 1 keys are not supported\n");
 271                 exit(1);
 272         }
 273         if (key_to_blob(k, &blob, &len) <= 0) {
 274                 fprintf(stderr, "key_to_blob failed\n");
 275                 exit(1);
 276         }
 277         /* Comment + surrounds must fit into 72 chars (RFC 4716 sec 3.3) */
 278         snprintf(comment, sizeof(comment),
 279             "%u-bit %s, converted by %s@%s from OpenSSH",
 280             key_size(k), key_type(k),
 281             pw->pw_name, hostname);
 282
 283         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_BEGIN);
 284         fprintf(stdout, "Comment: \"%s\"\n", comment);
 285         dump_base64(stdout, blob, len);
 286         fprintf(stdout, "%s\n", SSH_COM_PUBLIC_END);
 287         key_free(k);
 288         xfree(blob);
 289         exit(0);
 290 }
 291
 292 static void
 293 do_convert_to_pkcs8(Key *k)
 294 {
 295         switch (key_type_plain(k->type)) {
 296         case KEY_RSA1:
 297         case KEY_RSA:
 298                 if (!PEM_write_RSA_PUBKEY(stdout, k->rsa))
 299                         fatal("PEM_write_RSA_PUBKEY failed");
 300                 break;
 301         case KEY_DSA:
 302                 if (!PEM_write_DSA_PUBKEY(stdout, k->dsa))
 303                         fatal("PEM_write_DSA_PUBKEY failed");
 304                 break;
 305 #ifdef OPENSSL_HAS_ECC
 306         case KEY_ECDSA:
 307                 if (!PEM_write_EC_PUBKEY(stdout, k->ecdsa))
 308                         fatal("PEM_write_EC_PUBKEY failed");
 309                 break;
 310 #endif
 311         default:
 312                 fatal("%s: unsupported key type %s", __func__, key_type(k));
 313         }
 314         exit(0);
 315 }
 316
 317 static void
 318 do_convert_to_pem(Key *k)
 319 {
 320         switch (key_type_plain(k->type)) {
 321         case KEY_RSA1:
 322         case KEY_RSA:
 323                 if (!PEM_write_RSAPublicKey(stdout, k->rsa))
 324                         fatal("PEM_write_RSAPublicKey failed");
 325                 break;
 326 #if notyet /* OpenSSH 0.9.8 lacks this function */
 327         case KEY_DSA:
 328                 if (!PEM_write_DSAPublicKey(stdout, k->dsa))
 329                         fatal("PEM_write_DSAPublicKey failed");
 330                 break;
 331 #endif
 332         /* XXX ECDSA? */
 333         default:
 334                 fatal("%s: unsupported key type %s", __func__, key_type(k));
 335         }
 336         exit(0);
 337 }
 338
 339 static void
 340 do_convert_to(struct passwd *pw)
 341 {
 342         Key *k;
 343         struct stat st;
 344
 345         if (!have_identity)
 346                 ask_filename(pw, "Enter file in which the key is");
 347         if (stat(identity_file, &st) < 0)
 348                 fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
 349         if ((k = key_load_public(identity_file, NULL)) == NULL) {
 350                 if ((k = load_identity(identity_file)) == NULL) {
 351                         fprintf(stderr, "load failed\n");
 352                         exit(1);
 353                 }
 354         }
 355
 356         switch (convert_format) {
 357         case FMT_RFC4716:
 358                 do_convert_to_ssh2(pw, k);
 359                 break;
 360         case FMT_PKCS8:
 361                 do_convert_to_pkcs8(k);
 362                 break;
 363         case FMT_PEM:
 364                 do_convert_to_pem(k);
 365                 break;
 366         default:
 367                 fatal("%s: unknown key format %d", __func__, convert_format);
 368         }
 369         exit(0);
 370 }
 371
 372 static void
 373 buffer_get_bignum_bits(Buffer *b, BIGNUM *value)
 374 {
 375         u_int bignum_bits = buffer_get_int(b);
 376         u_int bytes = (bignum_bits + 7) / 8;
 377
 378         if (buffer_len(b) < bytes)
 379                 fatal("buffer_get_bignum_bits: input buffer too small: "
 380                     "need %d have %d", bytes, buffer_len(b));
 381         if (BN_bin2bn(buffer_ptr(b), bytes, value) == NULL)
 382                 fatal("buffer_get_bignum_bits: BN_bin2bn failed");
 383         buffer_consume(b, bytes);
 384 }
 385
 386 static Key *
 387 do_convert_private_ssh2_from_blob(u_char *blob, u_int blen)
 388 {
 389         Buffer b;
 390         Key *key = NULL;
 391         char *type, *cipher;
 392         u_char *sig, data[] = "abcde12345";
 393         int magic, rlen, ktype, i1, i2, i3, i4;
 394         u_int slen;
 395         u_long e;
 396
 397         buffer_init(&b);
 398         buffer_append(&b, blob, blen);
 399
 400         magic = buffer_get_int(&b);
 401         if (magic != SSH_COM_PRIVATE_KEY_MAGIC) {
 402                 error("bad magic 0x%x != 0x%x", magic, SSH_COM_PRIVATE_KEY_MAGIC);
 403                 buffer_free(&b);
 404                 return NULL;
 405         }
 406         i1 = buffer_get_int(&b);
 407         type   = buffer_get_string(&b, NULL);
 408         cipher = buffer_get_string(&b, NULL);
 409         i2 = buffer_get_int(&b);
 410         i3 = buffer_get_int(&b);
 411         i4 = buffer_get_int(&b);
 412         debug("ignore (%d %d %d %d)", i1, i2, i3, i4);
 413         if (strcmp(cipher, "none") != 0) {
 414                 error("unsupported cipher %s", cipher);
 415                 xfree(cipher);
 416                 buffer_free(&b);
 417                 xfree(type);
 418                 return NULL;
 419         }
 420         xfree(cipher);
 421
 422         if (strstr(type, "dsa")) {
 423                 ktype = KEY_DSA;
 424         } else if (strstr(type, "rsa")) {
 425                 ktype = KEY_RSA;
 426         } else {
 427                 buffer_free(&b);
 428                 xfree(type);
 429                 return NULL;
 430         }
 431         key = key_new_private(ktype);
 432         xfree(type);
 433
 434         switch (key->type) {
 435         case KEY_DSA:
 436                 buffer_get_bignum_bits(&b, key->dsa->p);
 437                 buffer_get_bignum_bits(&b, key->dsa->g);
 438                 buffer_get_bignum_bits(&b, key->dsa->q);
 439                 buffer_get_bignum_bits(&b, key->dsa->pub_key);
 440                 buffer_get_bignum_bits(&b, key->dsa->priv_key);
 441                 break;
 442         case KEY_RSA:
 443                 e = buffer_get_char(&b);
 444                 debug("e %lx", e);
 445                 if (e < 30) {
 446                         e <<= 8;
 447                         e += buffer_get_char(&b);
 448                         debug("e %lx", e);
 449                         e <<= 8;
 450                         e += buffer_get_char(&b);
 451                         debug("e %lx", e);
 452                 }
 453                 if (!BN_set_word(key->rsa->e, e)) {
 454                         buffer_free(&b);
 455                         key_free(key);
 456                         return NULL;
 457                 }
 458                 buffer_get_bignum_bits(&b, key->rsa->d);
 459                 buffer_get_bignum_bits(&b, key->rsa->n);
 460                 buffer_get_bignum_bits(&b, key->rsa->iqmp);
 461                 buffer_get_bignum_bits(&b, key->rsa->q);
 462                 buffer_get_bignum_bits(&b, key->rsa->p);
 463                 rsa_generate_additional_parameters(key->rsa);
 464                 break;
 465         }
 466         rlen = buffer_len(&b);
 467         if (rlen != 0)
 468                 error("do_convert_private_ssh2_from_blob: "
 469                     "remaining bytes in key blob %d", rlen);
 470         buffer_free(&b);
 471
 472         /* try the key */
 473         key_sign(key, &sig, &slen, data, sizeof(data));
 474         key_verify(key, sig, slen, data, sizeof(data));
 475         xfree(sig);
 476         return key;
 477 }
 478
 479 static int
 480 get_line(FILE *fp, char *line, size_t len)
 481 {
 482         int c;
 483         size_t pos = 0;
 484
 485         line[0] = '\0';
 486         while ((c = fgetc(fp)) != EOF) {
 487                 if (pos >= len - 1) {
 488                         fprintf(stderr, "input line too long.\n");
 489                         exit(1);
 490                 }
 491                 switch (c) {
 492                 case '\r':
 493                         c = fgetc(fp);
 494                         if (c != EOF && c != '\n' && ungetc(c, fp) == EOF) {
 495                                 fprintf(stderr, "unget: %s\n", strerror(errno));
 496                                 exit(1);
 497                         }
 498                         return pos;
 499                 case '\n':
 500                         return pos;
 501                 }
 502                 line[pos++] = c;
 503                 line[pos] = '\0';
 504         }
 505         /* We reached EOF */
 506         return -1;
 507 }
 508
 509 static void
 510 do_convert_from_ssh2(struct passwd *pw, Key **k, int *private)
 511 {
 512         int blen;
 513         u_int len;
 514         char line[1024];
 515         u_char blob[8096];
 516         char encoded[8096];
 517         int escaped = 0;
 518         FILE *fp;
 519
 520         if ((fp = fopen(identity_file, "r")) == NULL)
 521                 fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
 522         encoded[0] = '\0';
 523         while ((blen = get_line(fp, line, sizeof(line))) != -1) {
 524                 if (line[blen - 1] == '\\')
 525                         escaped++;
 526                 if (strncmp(line, "----", 4) == 0 ||
 527                     strstr(line, ": ") != NULL) {
 528                         if (strstr(line, SSH_COM_PRIVATE_BEGIN) != NULL)
 529                                 *private = 1;
 530                         if (strstr(line, " END ") != NULL) {
 531                                 break;
 532                         }
 533                         /* fprintf(stderr, "ignore: %s", line); */
 534                         continue;
 535                 }
 536                 if (escaped) {
 537                         escaped--;
 538                         /* fprintf(stderr, "escaped: %s", line); */
 539                         continue;
 540                 }
 541                 strlcat(encoded, line, sizeof(encoded));
 542         }
 543         len = strlen(encoded);
 544         if (((len % 4) == 3) &&
 545             (encoded[len-1] == '=') &&
 546             (encoded[len-2] == '=') &&
 547             (encoded[len-3] == '='))
 548                 encoded[len-3] = '\0';
 549         blen = uudecode(encoded, blob, sizeof(blob));
 550         if (blen < 0) {
 551                 fprintf(stderr, "uudecode failed.\n");
 552                 exit(1);
 553         }
 554         *k = *private ?
 555             do_convert_private_ssh2_from_blob(blob, blen) :
 556             key_from_blob(blob, blen);
 557         if (*k == NULL) {
 558                 fprintf(stderr, "decode blob failed.\n");
 559                 exit(1);
 560         }
 561         fclose(fp);
 562 }
 563
 564 static void
 565 do_convert_from_pkcs8(Key **k, int *private)
 566 {
 567         EVP_PKEY *pubkey;
 568         FILE *fp;
 569
 570         if ((fp = fopen(identity_file, "r")) == NULL)
 571                 fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
 572         if ((pubkey = PEM_read_PUBKEY(fp, NULL, NULL, NULL)) == NULL) {
 573                 fatal("%s: %s is not a recognised public key format", __func__,
 574                     identity_file);
 575         }
 576         fclose(fp);
 577         switch (EVP_PKEY_type(pubkey->type)) {
 578         case EVP_PKEY_RSA:
 579                 *k = key_new(KEY_UNSPEC);
 580                 (*k)->type = KEY_RSA;
 581                 (*k)->rsa = EVP_PKEY_get1_RSA(pubkey);
 582                 break;
 583         case EVP_PKEY_DSA:
 584                 *k = key_new(KEY_UNSPEC);
 585                 (*k)->type = KEY_DSA;
 586                 (*k)->dsa = EVP_PKEY_get1_DSA(pubkey);
 587                 break;
 588 #ifdef OPENSSL_HAS_ECC
 589         case EVP_PKEY_EC:
 590                 *k = key_new(KEY_UNSPEC);
 591                 (*k)->type = KEY_ECDSA;
 592                 (*k)->ecdsa = EVP_PKEY_get1_EC_KEY(pubkey);
 593                 (*k)->ecdsa_nid = key_ecdsa_key_to_nid((*k)->ecdsa);
 594                 break;
 595 #endif
 596         default:
 597                 fatal("%s: unsupported pubkey type %d", __func__,
 598                     EVP_PKEY_type(pubkey->type));
 599         }
 600         EVP_PKEY_free(pubkey);
 601         return;
 602 }
 603
 604 static void
 605 do_convert_from_pem(Key **k, int *private)
 606 {
 607         FILE *fp;
 608         RSA *rsa;
 609 #ifdef notyet
 610         DSA *dsa;
 611 #endif
 612
 613         if ((fp = fopen(identity_file, "r")) == NULL)
 614                 fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
 615         if ((rsa = PEM_read_RSAPublicKey(fp, NULL, NULL, NULL)) != NULL) {
 616                 *k = key_new(KEY_UNSPEC);
 617                 (*k)->type = KEY_RSA;
 618                 (*k)->rsa = rsa;
 619                 fclose(fp);
 620                 return;
 621         }
 622 #if notyet /* OpenSSH 0.9.8 lacks this function */
 623         rewind(fp);
 624         if ((dsa = PEM_read_DSAPublicKey(fp, NULL, NULL, NULL)) != NULL) {
 625                 *k = key_new(KEY_UNSPEC);
 626                 (*k)->type = KEY_DSA;
 627                 (*k)->dsa = dsa;
 628                 fclose(fp);
 629                 return;
 630         }
 631         /* XXX ECDSA */
 632 #endif
 633         fatal("%s: unrecognised raw private key format", __func__);
 634 }
 635
 636 static void
 637 do_convert_from(struct passwd *pw)
 638 {
 639         Key *k = NULL;
 640         int private = 0, ok = 0;
 641         struct stat st;
 642
 643         if (!have_identity)
 644                 ask_filename(pw, "Enter file in which the key is");
 645         if (stat(identity_file, &st) < 0)
 646                 fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
 647
 648         switch (convert_format) {
 649         case FMT_RFC4716:
 650                 do_convert_from_ssh2(pw, &k, &private);
 651                 break;
 652         case FMT_PKCS8:
 653                 do_convert_from_pkcs8(&k, &private);
 654                 break;
 655         case FMT_PEM:
 656                 do_convert_from_pem(&k, &private);
 657                 break;
 658         default:
 659                 fatal("%s: unknown key format %d", __func__, convert_format);
 660         }
 661
 662         if (!private)
 663                 ok = key_write(k, stdout);
 664                 if (ok)
 665                         fprintf(stdout, "\n");
 666         else {
 667                 switch (k->type) {
 668                 case KEY_DSA:
 669                         ok = PEM_write_DSAPrivateKey(stdout, k->dsa, NULL,
 670                             NULL, 0, NULL, NULL);
 671                         break;
 672 #ifdef OPENSSL_HAS_ECC
 673                 case KEY_ECDSA:
 674                         ok = PEM_write_ECPrivateKey(stdout, k->ecdsa, NULL,
 675                             NULL, 0, NULL, NULL);
 676                         break;
 677 #endif
 678                 case KEY_RSA:
 679                         ok = PEM_write_RSAPrivateKey(stdout, k->rsa, NULL,
 680                             NULL, 0, NULL, NULL);
 681                         break;
 682                 default:
 683                         fatal("%s: unsupported key type %s", __func__,
 684                             key_type(k));
 685                 }
 686         }
 687
 688         if (!ok) {
 689                 fprintf(stderr, "key write failed\n");
 690                 exit(1);
 691         }
 692         key_free(k);
 693         exit(0);
 694 }
 695
 696 static void
 697 do_print_public(struct passwd *pw)
 698 {
 699         Key *prv;
 700         struct stat st;
 701
 702         if (!have_identity)
 703                 ask_filename(pw, "Enter file in which the key is");
 704         if (stat(identity_file, &st) < 0) {
 705                 perror(identity_file);
 706                 exit(1);
 707         }
 708         prv = load_identity(identity_file);
 709         if (prv == NULL) {
 710                 fprintf(stderr, "load failed\n");
 711                 exit(1);
 712         }
 713         if (!key_write(prv, stdout))
 714                 fprintf(stderr, "key_write failed");
 715         key_free(prv);
 716         fprintf(stdout, "\n");
 717         exit(0);
 718 }
 719
 720 static void
 721 do_download(struct passwd *pw)
 722 {
 723 #ifdef ENABLE_PKCS11
 724         Key **keys = NULL;
 725         int i, nkeys;
 726
 727         pkcs11_init(0);
 728         nkeys = pkcs11_add_provider(pkcs11provider, NULL, &keys);
 729         if (nkeys <= 0)
 730                 fatal("cannot read public key from pkcs11");
 731         for (i = 0; i < nkeys; i++) {
 732                 key_write(keys[i], stdout);
 733                 key_free(keys[i]);
 734                 fprintf(stdout, "\n");
 735         }
 736         xfree(keys);
 737         pkcs11_terminate();
 738         exit(0);
 739 #else
 740         fatal("no pkcs11 support");
 741 #endif /* ENABLE_PKCS11 */
 742 }
 743
 744 static void
 745 do_fingerprint(struct passwd *pw)
 746 {
 747         FILE *f;
 748         Key *public;
 749         char *comment = NULL, *cp, *ep, line[16*1024], *fp, *ra;
 750         int i, skip = 0, num = 0, invalid = 1;
 751         enum fp_rep rep;
 752         enum fp_type fptype;
 753         struct stat st;
 754
 755         fptype = print_bubblebabble ? SSH_FP_SHA1 : SSH_FP_MD5;
 756         rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_HEX;
 757
 758         if (!have_identity)
 759                 ask_filename(pw, "Enter file in which the key is");
 760         if (stat(identity_file, &st) < 0) {
 761                 perror(identity_file);
 762                 exit(1);
 763         }
 764         public = key_load_public(identity_file, &comment);
 765         if (public != NULL) {
 766                 fp = key_fingerprint(public, fptype, rep);
 767                 ra = key_fingerprint(public, SSH_FP_MD5, SSH_FP_RANDOMART);
 768                 printf("%u %s %s (%s)\n", key_size(public), fp, comment,
 769                     key_type(public));
 770                 if (log_level >= SYSLOG_LEVEL_VERBOSE)
 771                         printf("%s\n", ra);
 772                 key_free(public);
 773                 xfree(comment);
 774                 xfree(ra);
 775                 xfree(fp);
 776                 exit(0);
 777         }
 778         if (comment) {
 779                 xfree(comment);
 780                 comment = NULL;
 781         }
 782
 783         if ((f = fopen(identity_file, "r")) == NULL)
 784                 fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
 785
 786         while (fgets(line, sizeof(line), f)) {
 787                 if ((cp = strchr(line, '\n')) == NULL) {
 788                         error("line %d too long: %.40s...",
 789                             num + 1, line);
 790                         skip = 1;
 791                         continue;
 792                 }
 793                 num++;
 794                 if (skip) {
 795                         skip = 0;
 796                         continue;
 797                 }
 798                 *cp = '\0';
 799
 800                 /* Skip leading whitespace, empty and comment lines. */
 801                 for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
 802                         ;
 803                 if (!*cp || *cp == '\n' || *cp == '#')
 804                         continue;
 805                 i = strtol(cp, &ep, 10);
 806                 if (i == 0 || ep == NULL || (*ep != ' ' && *ep != '\t')) {
 807                         int quoted = 0;
 808                         comment = cp;
 809                         for (; *cp && (quoted || (*cp != ' ' &&
 810                             *cp != '\t')); cp++) {
 811                                 if (*cp == '\\' && cp[1] == '"')
 812                                         cp++;   /* Skip both */
 813                                 else if (*cp == '"')
 814                                         quoted = !quoted;
 815                         }
 816                         if (!*cp)
 817                                 continue;
 818                         *cp++ = '\0';
 819                 }
 820                 ep = cp;
 821                 public = key_new(KEY_RSA1);
 822                 if (key_read(public, &cp) != 1) {
 823                         cp = ep;
 824                         key_free(public);
 825                         public = key_new(KEY_UNSPEC);
 826                         if (key_read(public, &cp) != 1) {
 827                                 key_free(public);
 828                                 continue;
 829                         }
 830                 }
 831                 comment = *cp ? cp : comment;
 832                 fp = key_fingerprint(public, fptype, rep);
 833                 ra = key_fingerprint(public, SSH_FP_MD5, SSH_FP_RANDOMART);
 834                 printf("%u %s %s (%s)\n", key_size(public), fp,
 835                     comment ? comment : "no comment", key_type(public));
 836                 if (log_level >= SYSLOG_LEVEL_VERBOSE)
 837                         printf("%s\n", ra);
 838                 xfree(ra);
 839                 xfree(fp);
 840                 key_free(public);
 841                 invalid = 0;
 842         }
 843         fclose(f);
 844
 845         if (invalid) {
 846                 printf("%s is not a public key file.\n", identity_file);
 847                 exit(1);
 848         }
 849         exit(0);
 850 }
 851
 852 static void
 853 do_gen_all_hostkeys(struct passwd *pw)
 854 {
 855         struct {
 856                 char *key_type;
 857                 char *key_type_display;
 858                 char *path;
 859         } key_types[] = {
 860                 { "rsa1", "RSA1", _PATH_HOST_KEY_FILE },
 861                 { "rsa", "RSA" ,_PATH_HOST_RSA_KEY_FILE },
 862                 { "dsa", "DSA", _PATH_HOST_DSA_KEY_FILE },
 863 #ifdef OPENSSL_HAS_ECC
 864                 { "ecdsa", "ECDSA",_PATH_HOST_ECDSA_KEY_FILE },
 865 #endif
 866                 { NULL, NULL, NULL }
 867         };
 868
 869         int first = 0;
 870         struct stat st;
 871         Key *private, *public;
 872         char comment[1024];
 873         int i, type, fd;
 874         FILE *f;
 875
 876         for (i = 0; key_types[i].key_type; i++) {
 877                 if (stat(key_types[i].path, &st) == 0)
 878                         continue;
 879                 if (errno != ENOENT) {
 880                         printf("Could not stat %s: %s", key_types[i].path,
 881                             strerror(errno));
 882                         first = 0;
 883                         continue;
 884                 }
 885
 886                 if (first == 0) {
 887                         first = 1;
 888                         printf("%s: generating new host keys: ", __progname);
 889                 }
 890                 printf("%s ", key_types[i].key_type_display);
 891                 fflush(stdout);
 892                 arc4random_stir();
 893                 type = key_type_from_name(key_types[i].key_type);
 894                 strlcpy(identity_file, key_types[i].path, sizeof(identity_file));
 895                 bits = 0;
 896                 type_bits_valid(type, &bits);
 897                 private = key_generate(type, bits);
 898                 if (private == NULL) {
 899                         fprintf(stderr, "key_generate failed\n");
 900                         first = 0;
 901                         continue;
 902                 }
 903                 public  = key_from_private(private);
 904                 snprintf(comment, sizeof comment, "%s@%s", pw->pw_name,
 905                     hostname);
 906                 if (!key_save_private(private, identity_file, "", comment)) {
 907                         printf("Saving the key failed: %s.\n", identity_file);
 908                         key_free(private);
 909                         key_free(public);
 910                         first = 0;
 911                         continue;
 912                 }
 913                 key_free(private);
 914                 arc4random_stir();
 915                 strlcat(identity_file, ".pub", sizeof(identity_file));
 916                 fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 917                 if (fd == -1) {
 918                         printf("Could not save your public key in %s\n",
 919                             identity_file);
 920                         key_free(public);
 921                         first = 0;
 922                         continue;
 923                 }
 924                 f = fdopen(fd, "w");
 925                 if (f == NULL) {
 926                         printf("fdopen %s failed\n", identity_file);
 927                         key_free(public);
 928                         first = 0;
 929                         continue;
 930                 }
 931                 if (!key_write(public, f)) {
 932                         fprintf(stderr, "write key failed\n");
 933                         key_free(public);
 934                         first = 0;
 935                         continue;
 936                 }
 937                 fprintf(f, " %s\n", comment);
 938                 fclose(f);
 939                 key_free(public);
 940
 941         }
 942         if (first != 0)
 943                 printf("\n");
 944 }
 945
 946 static void
 947 printhost(FILE *f, const char *name, Key *public, int ca, int hash)
 948 {
 949         if (print_fingerprint) {
 950                 enum fp_rep rep;
 951                 enum fp_type fptype;
 952                 char *fp, *ra;
 953
 954                 fptype = print_bubblebabble ? SSH_FP_SHA1 : SSH_FP_MD5;
 955                 rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_HEX;
 956                 fp = key_fingerprint(public, fptype, rep);
 957                 ra = key_fingerprint(public, SSH_FP_MD5, SSH_FP_RANDOMART);
 958                 printf("%u %s %s (%s)\n", key_size(public), fp, name,
 959                     key_type(public));
 960                 if (log_level >= SYSLOG_LEVEL_VERBOSE)
 961                         printf("%s\n", ra);
 962                 xfree(ra);
 963                 xfree(fp);
 964         } else {
 965                 if (hash && (name = host_hash(name, NULL, 0)) == NULL)
 966                         fatal("hash_host failed");
 967                 fprintf(f, "%s%s%s ", ca ? CA_MARKER : "", ca ? " " : "", name);
 968                 if (!key_write(public, f))
 969                         fatal("key_write failed");
 970                 fprintf(f, "\n");
 971         }
 972 }
 973
 974 static void
 975 do_known_hosts(struct passwd *pw, const char *name)
 976 {
 977         FILE *in, *out = stdout;
 978         Key *pub;
 979         char *cp, *cp2, *kp, *kp2;
 980         char line[16*1024], tmp[MAXPATHLEN], old[MAXPATHLEN];
 981         int c, skip = 0, inplace = 0, num = 0, invalid = 0, has_unhashed = 0;
 982         int ca;
 983
 984         if (!have_identity) {
 985                 cp = tilde_expand_filename(_PATH_SSH_USER_HOSTFILE, pw->pw_uid);
 986                 if (strlcpy(identity_file, cp, sizeof(identity_file)) >=
 987                     sizeof(identity_file))
 988                         fatal("Specified known hosts path too long");
 989                 xfree(cp);
 990                 have_identity = 1;
 991         }
 992         if ((in = fopen(identity_file, "r")) == NULL)
 993                 fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
 994
 995         /*
 996          * Find hosts goes to stdout, hash and deletions happen in-place
 997          * A corner case is ssh-keygen -HF foo, which should go to stdout
 998          */
 999         if (!find_host && (hash_hosts || delete_host)) {
1000                 if (strlcpy(tmp, identity_file, sizeof(tmp)) >= sizeof(tmp) ||
1001                     strlcat(tmp, ".XXXXXXXXXX", sizeof(tmp)) >= sizeof(tmp) ||
1002                     strlcpy(old, identity_file, sizeof(old)) >= sizeof(old) ||
1003                     strlcat(old, ".old", sizeof(old)) >= sizeof(old))
1004                         fatal("known_hosts path too long");
1005                 umask(077);
1006                 if ((c = mkstemp(tmp)) == -1)
1007                         fatal("mkstemp: %s", strerror(errno));
1008                 if ((out = fdopen(c, "w")) == NULL) {
1009                         c = errno;
1010                         unlink(tmp);
1011                         fatal("fdopen: %s", strerror(c));
1012                 }
1013                 inplace = 1;
1014         }
1015
1016         while (fgets(line, sizeof(line), in)) {
1017                 if ((cp = strchr(line, '\n')) == NULL) {
1018                         error("line %d too long: %.40s...", num + 1, line);
1019                         skip = 1;
1020                         invalid = 1;
1021                         continue;
1022                 }
1023                 num++;
1024                 if (skip) {
1025                         skip = 0;
1026                         continue;
1027                 }
1028                 *cp = '\0';
1029
1030                 /* Skip leading whitespace, empty and comment lines. */
1031                 for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
1032                         ;
1033                 if (!*cp || *cp == '\n' || *cp == '#') {
1034                         if (inplace)
1035                                 fprintf(out, "%s\n", cp);
1036                         continue;
1037                 }
1038                 /* Check whether this is a CA key */
1039                 if (strncasecmp(cp, CA_MARKER, sizeof(CA_MARKER) - 1) == 0 &&
1040                     (cp[sizeof(CA_MARKER) - 1] == ' ' ||
1041                     cp[sizeof(CA_MARKER) - 1] == '\t')) {
1042                         ca = 1;
1043                         cp += sizeof(CA_MARKER);
1044                 } else
1045                         ca = 0;
1046
1047                 /* Find the end of the host name portion. */
1048                 for (kp = cp; *kp && *kp != ' ' && *kp != '\t'; kp++)
1049                         ;
1050
1051                 if (*kp == '\0' || *(kp + 1) == '\0') {
1052                         error("line %d missing key: %.40s...",
1053                             num, line);
1054                         invalid = 1;
1055                         continue;
1056                 }
1057                 *kp++ = '\0';
1058                 kp2 = kp;
1059
1060                 pub = key_new(KEY_RSA1);
1061                 if (key_read(pub, &kp) != 1) {
1062                         kp = kp2;
1063                         key_free(pub);
1064                         pub = key_new(KEY_UNSPEC);
1065                         if (key_read(pub, &kp) != 1) {
1066                                 error("line %d invalid key: %.40s...",
1067                                     num, line);
1068                                 key_free(pub);
1069                                 invalid = 1;
1070                                 continue;
1071                         }
1072                 }
1073
1074                 if (*cp == HASH_DELIM) {
1075                         if (find_host || delete_host) {
1076                                 cp2 = host_hash(name, cp, strlen(cp));
1077                                 if (cp2 == NULL) {
1078                                         error("line %d: invalid hashed "
1079                                             "name: %.64s...", num, line);
1080                                         invalid = 1;
1081                                         continue;
1082                                 }
1083                                 c = (strcmp(cp2, cp) == 0);
1084                                 if (find_host && c) {
1085                                         printf("# Host %s found: "
1086                                             "line %d type %s%s\n", name,
1087                                             num, key_type(pub),
1088                                             ca ? " (CA key)" : "");
1089                                         printhost(out, cp, pub, ca, 0);
1090                                 }
1091                                 if (delete_host && !c && !ca)
1092                                         printhost(out, cp, pub, ca, 0);
1093                         } else if (hash_hosts)
1094                                 printhost(out, cp, pub, ca, 0);
1095                 } else {
1096                         if (find_host || delete_host) {
1097                                 c = (match_hostname(name, cp,
1098                                     strlen(cp)) == 1);
1099                                 if (find_host && c) {
1100                                         printf("# Host %s found: "
1101                                             "line %d type %s%s\n", name,
1102                                             num, key_type(pub),
1103                                             ca ? " (CA key)" : "");
1104                                         printhost(out, name, pub,
1105                                             ca, hash_hosts && !ca);
1106                                 }
1107                                 if (delete_host && !c && !ca)
1108                                         printhost(out, cp, pub, ca, 0);
1109                         } else if (hash_hosts) {
1110                                 for (cp2 = strsep(&cp, ",");
1111                                     cp2 != NULL && *cp2 != '\0';
1112                                     cp2 = strsep(&cp, ",")) {
1113                                         if (ca) {
1114                                                 fprintf(stderr, "Warning: "
1115                                                     "ignoring CA key for host: "
1116                                                     "%.64s\n", cp2);
1117                                                 printhost(out, cp2, pub, ca, 0);
1118                                         } else if (strcspn(cp2, "*?!") !=
1119                                             strlen(cp2)) {
1120                                                 fprintf(stderr, "Warning: "
1121                                                     "ignoring host name with "
1122                                                     "metacharacters: %.64s\n",
1123                                                     cp2);
1124                                                 printhost(out, cp2, pub, ca, 0);
1125                                         } else
1126                                                 printhost(out, cp2, pub, ca, 1);
1127                                 }
1128                                 has_unhashed = 1;
1129                         }
1130                 }
1131                 key_free(pub);
1132         }
1133         fclose(in);
1134
1135         if (invalid) {
1136                 fprintf(stderr, "%s is not a valid known_hosts file.\n",
1137                     identity_file);
1138                 if (inplace) {
1139                         fprintf(stderr, "Not replacing existing known_hosts "
1140                             "file because of errors\n");
1141                         fclose(out);
1142                         unlink(tmp);
1143                 }
1144                 exit(1);
1145         }
1146
1147         if (inplace) {
1148                 fclose(out);
1149
1150                 /* Backup existing file */
1151                 if (unlink(old) == -1 && errno != ENOENT)
1152                         fatal("unlink %.100s: %s", old, strerror(errno));
1153                 if (link(identity_file, old) == -1)
1154                         fatal("link %.100s to %.100s: %s", identity_file, old,
1155                             strerror(errno));
1156                 /* Move new one into place */
1157                 if (rename(tmp, identity_file) == -1) {
1158                         error("rename\"%s\" to \"%s\": %s", tmp, identity_file,
1159                             strerror(errno));
1160                         unlink(tmp);
1161                         unlink(old);
1162                         exit(1);
1163                 }
1164
1165                 fprintf(stderr, "%s updated.\n", identity_file);
1166                 fprintf(stderr, "Original contents retained as %s\n", old);
1167                 if (has_unhashed) {
1168                         fprintf(stderr, "WARNING: %s contains unhashed "
1169                             "entries\n", old);
1170                         fprintf(stderr, "Delete this file to ensure privacy "
1171                             "of hostnames\n");
1172                 }
1173         }
1174
1175         exit(0);
1176 }
1177
1178 /*
1179  * Perform changing a passphrase.  The argument is the passwd structure
1180  * for the current user.
1181  */
1182 static void
1183 do_change_passphrase(struct passwd *pw)
1184 {
1185         char *comment;
1186         char *old_passphrase, *passphrase1, *passphrase2;
1187         struct stat st;
1188         Key *private;
1189
1190         if (!have_identity)
1191                 ask_filename(pw, "Enter file in which the key is");
1192         if (stat(identity_file, &st) < 0) {
1193                 perror(identity_file);
1194                 exit(1);
1195         }
1196         /* Try to load the file with empty passphrase. */
1197         private = key_load_private(identity_file, "", &comment);
1198         if (private == NULL) {
1199                 if (identity_passphrase)
1200                         old_passphrase = xstrdup(identity_passphrase);
1201                 else
1202                         old_passphrase =
1203                             read_passphrase("Enter old passphrase: ",
1204                             RP_ALLOW_STDIN);
1205                 private = key_load_private(identity_file, old_passphrase,
1206                     &comment);
1207                 memset(old_passphrase, 0, strlen(old_passphrase));
1208                 xfree(old_passphrase);
1209                 if (private == NULL) {
1210                         printf("Bad passphrase.\n");
1211                         exit(1);
1212                 }
1213         }
1214         printf("Key has comment '%s'\n", comment);
1215
1216         /* Ask the new passphrase (twice). */
1217         if (identity_new_passphrase) {
1218                 passphrase1 = xstrdup(identity_new_passphrase);
1219                 passphrase2 = NULL;
1220         } else {
1221                 passphrase1 =
1222                         read_passphrase("Enter new passphrase (empty for no "
1223                             "passphrase): ", RP_ALLOW_STDIN);
1224                 passphrase2 = read_passphrase("Enter same passphrase again: ",
1225                     RP_ALLOW_STDIN);
1226
1227                 /* Verify that they are the same. */
1228                 if (strcmp(passphrase1, passphrase2) != 0) {
1229                         memset(passphrase1, 0, strlen(passphrase1));
1230                         memset(passphrase2, 0, strlen(passphrase2));
1231                         xfree(passphrase1);
1232                         xfree(passphrase2);
1233                         printf("Pass phrases do not match.  Try again.\n");
1234                         exit(1);
1235                 }
1236                 /* Destroy the other copy. */
1237                 memset(passphrase2, 0, strlen(passphrase2));
1238                 xfree(passphrase2);
1239         }
1240
1241         /* Save the file using the new passphrase. */
1242         if (!key_save_private(private, identity_file, passphrase1, comment)) {
1243                 printf("Saving the key failed: %s.\n", identity_file);
1244                 memset(passphrase1, 0, strlen(passphrase1));
1245                 xfree(passphrase1);
1246                 key_free(private);
1247                 xfree(comment);
1248                 exit(1);
1249         }
1250         /* Destroy the passphrase and the copy of the key in memory. */
1251         memset(passphrase1, 0, strlen(passphrase1));
1252         xfree(passphrase1);
1253         key_free(private);               /* Destroys contents */
1254         xfree(comment);
1255
1256         printf("Your identification has been saved with the new passphrase.\n");
1257         exit(0);
1258 }
1259
1260 /*
1261  * Print the SSHFP RR.
1262  */
1263 static int
1264 do_print_resource_record(struct passwd *pw, char *fname, char *hname)
1265 {
1266         Key *public;
1267         char *comment = NULL;
1268         struct stat st;
1269
1270         if (fname == NULL)
1271                 ask_filename(pw, "Enter file in which the key is");
1272         if (stat(fname, &st) < 0) {
1273                 if (errno == ENOENT)
1274                         return 0;
1275                 perror(fname);
1276                 exit(1);
1277         }
1278         public = key_load_public(fname, &comment);
1279         if (public != NULL) {
1280                 export_dns_rr(hname, public, stdout, print_generic);
1281                 key_free(public);
1282                 xfree(comment);
1283                 return 1;
1284         }
1285         if (comment)
1286                 xfree(comment);
1287
1288         printf("failed to read v2 public key from %s.\n", fname);
1289         exit(1);
1290 }
1291
1292 /*
1293  * Change the comment of a private key file.
1294  */
1295 static void
1296 do_change_comment(struct passwd *pw)
1297 {
1298         char new_comment[1024], *comment, *passphrase;
1299         Key *private;
1300         Key *public;
1301         struct stat st;
1302         FILE *f;
1303         int fd;
1304
1305         if (!have_identity)
1306                 ask_filename(pw, "Enter file in which the key is");
1307         if (stat(identity_file, &st) < 0) {
1308                 perror(identity_file);
1309                 exit(1);
1310         }
1311         private = key_load_private(identity_file, "", &comment);
1312         if (private == NULL) {
1313                 if (identity_passphrase)
1314                         passphrase = xstrdup(identity_passphrase);
1315                 else if (identity_new_passphrase)
1316                         passphrase = xstrdup(identity_new_passphrase);
1317                 else
1318                         passphrase = read_passphrase("Enter passphrase: ",
1319                             RP_ALLOW_STDIN);
1320                 /* Try to load using the passphrase. */
1321                 private = key_load_private(identity_file, passphrase, &comment);
1322                 if (private == NULL) {
1323                         memset(passphrase, 0, strlen(passphrase));
1324                         xfree(passphrase);
1325                         printf("Bad passphrase.\n");
1326                         exit(1);
1327                 }
1328         } else {
1329                 passphrase = xstrdup("");
1330         }
1331         if (private->type != KEY_RSA1) {
1332                 fprintf(stderr, "Comments are only supported for RSA1 keys.\n");
1333                 key_free(private);
1334                 exit(1);
1335         }
1336         printf("Key now has comment '%s'\n", comment);
1337
1338         if (identity_comment) {
1339                 strlcpy(new_comment, identity_comment, sizeof(new_comment));
1340         } else {
1341                 printf("Enter new comment: ");
1342                 fflush(stdout);
1343                 if (!fgets(new_comment, sizeof(new_comment), stdin)) {
1344                         memset(passphrase, 0, strlen(passphrase));
1345                         key_free(private);
1346                         exit(1);
1347                 }
1348                 new_comment[strcspn(new_comment, "\n")] = '\0';
1349         }
1350
1351         /* Save the file using the new passphrase. */
1352         if (!key_save_private(private, identity_file, passphrase, new_comment)) {
1353                 printf("Saving the key failed: %s.\n", identity_file);
1354                 memset(passphrase, 0, strlen(passphrase));
1355                 xfree(passphrase);
1356                 key_free(private);
1357                 xfree(comment);
1358                 exit(1);
1359         }
1360         memset(passphrase, 0, strlen(passphrase));
1361         xfree(passphrase);
1362         public = key_from_private(private);
1363         key_free(private);
1364
1365         strlcat(identity_file, ".pub", sizeof(identity_file));
1366         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
1367         if (fd == -1) {
1368                 printf("Could not save your public key in %s\n", identity_file);
1369                 exit(1);
1370         }
1371         f = fdopen(fd, "w");
1372         if (f == NULL) {
1373                 printf("fdopen %s failed\n", identity_file);
1374                 exit(1);
1375         }
1376         if (!key_write(public, f))
1377                 fprintf(stderr, "write key failed\n");
1378         key_free(public);
1379         fprintf(f, " %s\n", new_comment);
1380         fclose(f);
1381
1382         xfree(comment);
1383
1384         printf("The comment in your key file has been changed.\n");
1385         exit(0);
1386 }
1387
1388 static const char *
1389 fmt_validity(u_int64_t valid_from, u_int64_t valid_to)
1390 {
1391         char from[32], to[32];
1392         static char ret[64];
1393         time_t tt;
1394         struct tm *tm;
1395
1396         *from = *to = '\0';
1397         if (valid_from == 0 && valid_to == 0xffffffffffffffffULL)
1398                 return "forever";
1399
1400         if (valid_from != 0) {
1401                 /* XXX revisit INT_MAX in 2038 :) */
1402                 tt = valid_from > INT_MAX ? INT_MAX : valid_from;
1403                 tm = localtime(&tt);
1404                 strftime(from, sizeof(from), "%Y-%m-%dT%H:%M:%S", tm);
1405         }
1406         if (valid_to != 0xffffffffffffffffULL) {
1407                 /* XXX revisit INT_MAX in 2038 :) */
1408                 tt = valid_to > INT_MAX ? INT_MAX : valid_to;
1409                 tm = localtime(&tt);
1410                 strftime(to, sizeof(to), "%Y-%m-%dT%H:%M:%S", tm);
1411         }
1412
1413         if (valid_from == 0) {
1414                 snprintf(ret, sizeof(ret), "before %s", to);
1415                 return ret;
1416         }
1417         if (valid_to == 0xffffffffffffffffULL) {
1418                 snprintf(ret, sizeof(ret), "after %s", from);
1419                 return ret;
1420         }
1421
1422         snprintf(ret, sizeof(ret), "from %s to %s", from, to);
1423         return ret;
1424 }
1425
1426 static void
1427 add_flag_option(Buffer *c, const char *name)
1428 {
1429         debug3("%s: %s", __func__, name);
1430         buffer_put_cstring(c, name);
1431         buffer_put_string(c, NULL, 0);
1432 }
1433
1434 static void
1435 add_string_option(Buffer *c, const char *name, const char *value)
1436 {
1437         Buffer b;
1438
1439         debug3("%s: %s=%s", __func__, name, value);
1440         buffer_init(&b);
1441         buffer_put_cstring(&b, value);
1442
1443         buffer_put_cstring(c, name);
1444         buffer_put_string(c, buffer_ptr(&b), buffer_len(&b));
1445
1446         buffer_free(&b);
1447 }
1448
1449 #define OPTIONS_CRITICAL        1
1450 #define OPTIONS_EXTENSIONS      2
1451 static void
1452 prepare_options_buf(Buffer *c, int which)
1453 {
1454         buffer_clear(c);
1455         if ((which & OPTIONS_CRITICAL) != 0 &&
1456             certflags_command != NULL)
1457                 add_string_option(c, "force-command", certflags_command);
1458         if ((which & OPTIONS_EXTENSIONS) != 0 &&
1459             (certflags_flags & CERTOPT_X_FWD) != 0)
1460                 add_flag_option(c, "permit-X11-forwarding");
1461         if ((which & OPTIONS_EXTENSIONS) != 0 &&
1462             (certflags_flags & CERTOPT_AGENT_FWD) != 0)
1463                 add_flag_option(c, "permit-agent-forwarding");
1464         if ((which & OPTIONS_EXTENSIONS) != 0 &&
1465             (certflags_flags & CERTOPT_PORT_FWD) != 0)
1466                 add_flag_option(c, "permit-port-forwarding");
1467         if ((which & OPTIONS_EXTENSIONS) != 0 &&
1468             (certflags_flags & CERTOPT_PTY) != 0)
1469                 add_flag_option(c, "permit-pty");
1470         if ((which & OPTIONS_EXTENSIONS) != 0 &&
1471             (certflags_flags & CERTOPT_USER_RC) != 0)
1472                 add_flag_option(c, "permit-user-rc");
1473         if ((which & OPTIONS_CRITICAL) != 0 &&
1474             certflags_src_addr != NULL)
1475                 add_string_option(c, "source-address", certflags_src_addr);
1476 }
1477
1478 static Key *
1479 load_pkcs11_key(char *path)
1480 {
1481 #ifdef ENABLE_PKCS11
1482         Key **keys = NULL, *public, *private = NULL;
1483         int i, nkeys;
1484
1485         if ((public = key_load_public(path, NULL)) == NULL)
1486                 fatal("Couldn't load CA public key \"%s\"", path);
1487
1488         nkeys = pkcs11_add_provider(pkcs11provider, identity_passphrase, &keys);
1489         debug3("%s: %d keys", __func__, nkeys);
1490         if (nkeys <= 0)
1491                 fatal("cannot read public key from pkcs11");
1492         for (i = 0; i < nkeys; i++) {
1493                 if (key_equal_public(public, keys[i])) {
1494                         private = keys[i];
1495                         continue;
1496                 }
1497                 key_free(keys[i]);
1498         }
1499         xfree(keys);
1500         key_free(public);
1501         return private;
1502 #else
1503         fatal("no pkcs11 support");
1504 #endif /* ENABLE_PKCS11 */
1505 }
1506
1507 static void
1508 do_ca_sign(struct passwd *pw, int argc, char **argv)
1509 {
1510         int i, fd;
1511         u_int n;
1512         Key *ca, *public;
1513         char *otmp, *tmp, *cp, *out, *comment, **plist = NULL;
1514         FILE *f;
1515         int v00 = 0; /* legacy keys */
1516
1517         if (key_type_name != NULL) {
1518                 switch (key_type_from_name(key_type_name)) {
1519                 case KEY_RSA_CERT_V00:
1520                 case KEY_DSA_CERT_V00:
1521                         v00 = 1;
1522                         break;
1523                 case KEY_UNSPEC:
1524                         if (strcasecmp(key_type_name, "v00") == 0) {
1525                                 v00 = 1;
1526                                 break;
1527                         } else if (strcasecmp(key_type_name, "v01") == 0)
1528                                 break;
1529                         /* FALLTHROUGH */
1530                 default:
1531                         fprintf(stderr, "unknown key type %s\n", key_type_name);
1532                         exit(1);
1533                 }
1534         }
1535
1536         pkcs11_init(1);
1537         tmp = tilde_expand_filename(ca_key_path, pw->pw_uid);
1538         if (pkcs11provider != NULL) {
1539                 if ((ca = load_pkcs11_key(tmp)) == NULL)
1540                         fatal("No PKCS#11 key matching %s found", ca_key_path);
1541         } else if ((ca = load_identity(tmp)) == NULL)
1542                 fatal("Couldn't load CA key \"%s\"", tmp);
1543         xfree(tmp);
1544
1545         for (i = 0; i < argc; i++) {
1546                 /* Split list of principals */
1547                 n = 0;
1548                 if (cert_principals != NULL) {
1549                         otmp = tmp = xstrdup(cert_principals);
1550                         plist = NULL;
1551                         for (; (cp = strsep(&tmp, ",")) != NULL; n++) {
1552                                 plist = xrealloc(plist, n + 1, sizeof(*plist));
1553                                 if (*(plist[n] = xstrdup(cp)) == '\0')
1554                                         fatal("Empty principal name");
1555                         }
1556                         xfree(otmp);
1557                 }
1558
1559                 tmp = tilde_expand_filename(argv[i], pw->pw_uid);
1560                 if ((public = key_load_public(tmp, &comment)) == NULL)
1561                         fatal("%s: unable to open \"%s\"", __func__, tmp);
1562                 if (public->type != KEY_RSA && public->type != KEY_DSA &&
1563                     public->type != KEY_ECDSA)
1564                         fatal("%s: key \"%s\" type %s cannot be certified",
1565                             __func__, tmp, key_type(public));
1566
1567                 /* Prepare certificate to sign */
1568                 if (key_to_certified(public, v00) != 0)
1569                         fatal("Could not upgrade key %s to certificate", tmp);
1570                 public->cert->type = cert_key_type;
1571                 public->cert->serial = (u_int64_t)cert_serial;
1572                 public->cert->key_id = xstrdup(cert_key_id);
1573                 public->cert->nprincipals = n;
1574                 public->cert->principals = plist;
1575                 public->cert->valid_after = cert_valid_from;
1576                 public->cert->valid_before = cert_valid_to;
1577                 if (v00) {
1578                         prepare_options_buf(&public->cert->critical,
1579                             OPTIONS_CRITICAL|OPTIONS_EXTENSIONS);
1580                 } else {
1581                         prepare_options_buf(&public->cert->critical,
1582                             OPTIONS_CRITICAL);
1583                         prepare_options_buf(&public->cert->extensions,
1584                             OPTIONS_EXTENSIONS);
1585                 }
1586                 public->cert->signature_key = key_from_private(ca);
1587
1588                 if (key_certify(public, ca) != 0)
1589                         fatal("Couldn't not certify key %s", tmp);
1590
1591                 if ((cp = strrchr(tmp, '.')) != NULL && strcmp(cp, ".pub") == 0)
1592                         *cp = '\0';
1593                 xasprintf(&out, "%s-cert.pub", tmp);
1594                 xfree(tmp);
1595
1596                 if ((fd = open(out, O_WRONLY|O_CREAT|O_TRUNC, 0644)) == -1)
1597                         fatal("Could not open \"%s\" for writing: %s", out,
1598                             strerror(errno));
1599                 if ((f = fdopen(fd, "w")) == NULL)
1600                         fatal("%s: fdopen: %s", __func__, strerror(errno));
1601                 if (!key_write(public, f))
1602                         fatal("Could not write certified key to %s", out);
1603                 fprintf(f, " %s\n", comment);
1604                 fclose(f);
1605
1606                 if (!quiet) {
1607                         logit("Signed %s key %s: id \"%s\" serial %llu%s%s "
1608                             "valid %s", key_cert_type(public),
1609                             out, public->cert->key_id,
1610                             (unsigned long long)public->cert->serial,
1611                             cert_principals != NULL ? " for " : "",
1612                             cert_principals != NULL ? cert_principals : "",
1613                             fmt_validity(cert_valid_from, cert_valid_to));
1614                 }
1615
1616                 key_free(public);
1617                 xfree(out);
1618         }
1619         pkcs11_terminate();
1620         exit(0);
1621 }
1622
1623 static u_int64_t
1624 parse_relative_time(const char *s, time_t now)
1625 {
1626         int64_t mul, secs;
1627
1628         mul = *s == '-' ? -1 : 1;
1629
1630         if ((secs = convtime(s + 1)) == -1)
1631                 fatal("Invalid relative certificate time %s", s);
1632         if (mul == -1 && secs > now)
1633                 fatal("Certificate time %s cannot be represented", s);
1634         return now + (u_int64_t)(secs * mul);
1635 }
1636
1637 static u_int64_t
1638 parse_absolute_time(const char *s)
1639 {
1640         struct tm tm;
1641         time_t tt;
1642         char buf[32], *fmt;
1643
1644         /*
1645          * POSIX strptime says "The application shall ensure that there
1646          * is white-space or other non-alphanumeric characters between
1647          * any two conversion specifications" so arrange things this way.
1648          */
1649         switch (strlen(s)) {
1650         case 8:
1651                 fmt = "%Y-%m-%d";
1652                 snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2s", s, s + 4, s + 6);
1653                 break;
1654         case 14:
1655                 fmt = "%Y-%m-%dT%H:%M:%S";
1656                 snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2sT%.2s:%.2s:%.2s",
1657                     s, s + 4, s + 6, s + 8, s + 10, s + 12);
1658                 break;
1659         default:
1660                 fatal("Invalid certificate time format %s", s);
1661         }
1662
1663         bzero(&tm, sizeof(tm));
1664         if (strptime(buf, fmt, &tm) == NULL)
1665                 fatal("Invalid certificate time %s", s);
1666         if ((tt = mktime(&tm)) < 0)
1667                 fatal("Certificate time %s cannot be represented", s);
1668         return (u_int64_t)tt;
1669 }
1670
1671 static void
1672 parse_cert_times(char *timespec)
1673 {
1674         char *from, *to;
1675         time_t now = time(NULL);
1676         int64_t secs;
1677
1678         /* +timespec relative to now */
1679         if (*timespec == '+' && strchr(timespec, ':') == NULL) {
1680                 if ((secs = convtime(timespec + 1)) == -1)
1681                         fatal("Invalid relative certificate life %s", timespec);
1682                 cert_valid_to = now + secs;
1683                 /*
1684                  * Backdate certificate one minute to avoid problems on hosts
1685                  * with poorly-synchronised clocks.
1686                  */
1687                 cert_valid_from = ((now - 59)/ 60) * 60;
1688                 return;
1689         }
1690
1691         /*
1692          * from:to, where
1693          * from := [+-]timespec | YYYYMMDD | YYYYMMDDHHMMSS
1694          *   to := [+-]timespec | YYYYMMDD | YYYYMMDDHHMMSS
1695          */
1696         from = xstrdup(timespec);
1697         to = strchr(from, ':');
1698         if (to == NULL || from == to || *(to + 1) == '\0')
1699                 fatal("Invalid certificate life specification %s", timespec);
1700         *to++ = '\0';
1701
1702         if (*from == '-' || *from == '+')
1703                 cert_valid_from = parse_relative_time(from, now);
1704         else
1705                 cert_valid_from = parse_absolute_time(from);
1706
1707         if (*to == '-' || *to == '+')
1708                 cert_valid_to = parse_relative_time(to, cert_valid_from);
1709         else
1710                 cert_valid_to = parse_absolute_time(to);
1711
1712         if (cert_valid_to <= cert_valid_from)
1713                 fatal("Empty certificate validity interval");
1714         xfree(from);
1715 }
1716
1717 static void
1718 add_cert_option(char *opt)
1719 {
1720         char *val;
1721
1722         if (strcasecmp(opt, "clear") == 0)
1723                 certflags_flags = 0;
1724         else if (strcasecmp(opt, "no-x11-forwarding") == 0)
1725                 certflags_flags &= ~CERTOPT_X_FWD;
1726         else if (strcasecmp(opt, "permit-x11-forwarding") == 0)
1727                 certflags_flags |= CERTOPT_X_FWD;
1728         else if (strcasecmp(opt, "no-agent-forwarding") == 0)
1729                 certflags_flags &= ~CERTOPT_AGENT_FWD;
1730         else if (strcasecmp(opt, "permit-agent-forwarding") == 0)
1731                 certflags_flags |= CERTOPT_AGENT_FWD;
1732         else if (strcasecmp(opt, "no-port-forwarding") == 0)
1733                 certflags_flags &= ~CERTOPT_PORT_FWD;
1734         else if (strcasecmp(opt, "permit-port-forwarding") == 0)
1735                 certflags_flags |= CERTOPT_PORT_FWD;
1736         else if (strcasecmp(opt, "no-pty") == 0)
1737                 certflags_flags &= ~CERTOPT_PTY;
1738         else if (strcasecmp(opt, "permit-pty") == 0)
1739                 certflags_flags |= CERTOPT_PTY;
1740         else if (strcasecmp(opt, "no-user-rc") == 0)
1741                 certflags_flags &= ~CERTOPT_USER_RC;
1742         else if (strcasecmp(opt, "permit-user-rc") == 0)
1743                 certflags_flags |= CERTOPT_USER_RC;
1744         else if (strncasecmp(opt, "force-command=", 14) == 0) {
1745                 val = opt + 14;
1746                 if (*val == '\0')
1747                         fatal("Empty force-command option");
1748                 if (certflags_command != NULL)
1749                         fatal("force-command already specified");
1750                 certflags_command = xstrdup(val);
1751         } else if (strncasecmp(opt, "source-address=", 15) == 0) {
1752                 val = opt + 15;
1753                 if (*val == '\0')
1754                         fatal("Empty source-address option");
1755                 if (certflags_src_addr != NULL)
1756                         fatal("source-address already specified");
1757                 if (addr_match_cidr_list(NULL, val) != 0)
1758                         fatal("Invalid source-address list");
1759                 certflags_src_addr = xstrdup(val);
1760         } else
1761                 fatal("Unsupported certificate option \"%s\"", opt);
1762 }
1763
1764 static void
1765 show_options(const Buffer *optbuf, int v00, int in_critical)
1766 {
1767         u_char *name, *data;
1768         u_int dlen;
1769         Buffer options, option;
1770
1771         buffer_init(&options);
1772         buffer_append(&options, buffer_ptr(optbuf), buffer_len(optbuf));
1773
1774         buffer_init(&option);
1775         while (buffer_len(&options) != 0) {
1776                 name = buffer_get_string(&options, NULL);
1777                 data = buffer_get_string_ptr(&options, &dlen);
1778                 buffer_append(&option, data, dlen);
1779                 printf("                %s", name);
1780                 if ((v00 || !in_critical) &&
1781                     (strcmp(name, "permit-X11-forwarding") == 0 ||
1782                     strcmp(name, "permit-agent-forwarding") == 0 ||
1783                     strcmp(name, "permit-port-forwarding") == 0 ||
1784                     strcmp(name, "permit-pty") == 0 ||
1785                     strcmp(name, "permit-user-rc") == 0))
1786                         printf("\n");
1787                 else if ((v00 || in_critical) &&
1788                     (strcmp(name, "force-command") == 0 ||
1789                     strcmp(name, "source-address") == 0)) {
1790                         data = buffer_get_string(&option, NULL);
1791                         printf(" %s\n", data);
1792                         xfree(data);
1793                 } else {
1794                         printf(" UNKNOWN OPTION (len %u)\n",
1795                             buffer_len(&option));
1796                         buffer_clear(&option);
1797                 }
1798                 xfree(name);
1799                 if (buffer_len(&option) != 0)
1800                         fatal("Option corrupt: extra data at end");
1801         }
1802         buffer_free(&option);
1803         buffer_free(&options);
1804 }
1805
1806 static void
1807 do_show_cert(struct passwd *pw)
1808 {
1809         Key *key;
1810         struct stat st;
1811         char *key_fp, *ca_fp;
1812         u_int i, v00;
1813
1814         if (!have_identity)
1815                 ask_filename(pw, "Enter file in which the key is");
1816         if (stat(identity_file, &st) < 0)
1817                 fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
1818         if ((key = key_load_public(identity_file, NULL)) == NULL)
1819                 fatal("%s is not a public key", identity_file);
1820         if (!key_is_cert(key))
1821                 fatal("%s is not a certificate", identity_file);
1822         v00 = key->type == KEY_RSA_CERT_V00 || key->type == KEY_DSA_CERT_V00;
1823
1824         key_fp = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX);
1825         ca_fp = key_fingerprint(key->cert->signature_key,
1826             SSH_FP_MD5, SSH_FP_HEX);
1827
1828         printf("%s:\n", identity_file);
1829         printf("        Type: %s %s certificate\n", key_ssh_name(key),
1830             key_cert_type(key));
1831         printf("        Public key: %s %s\n", key_type(key), key_fp);
1832         printf("        Signing CA: %s %s\n",
1833             key_type(key->cert->signature_key), ca_fp);
1834         printf("        Key ID: \"%s\"\n", key->cert->key_id);
1835         if (!v00) {
1836                 printf("        Serial: %llu\n",
1837                     (unsigned long long)key->cert->serial);
1838         }
1839         printf("        Valid: %s\n",
1840             fmt_validity(key->cert->valid_after, key->cert->valid_before));
1841         printf("        Principals: ");
1842         if (key->cert->nprincipals == 0)
1843                 printf("(none)\n");
1844         else {
1845                 for (i = 0; i < key->cert->nprincipals; i++)
1846                         printf("\n                %s",
1847                             key->cert->principals[i]);
1848                 printf("\n");
1849         }
1850         printf("        Critical Options: ");
1851         if (buffer_len(&key->cert->critical) == 0)
1852                 printf("(none)\n");
1853         else {
1854                 printf("\n");
1855                 show_options(&key->cert->critical, v00, 1);
1856         }
1857         if (!v00) {
1858                 printf("        Extensions: ");
1859                 if (buffer_len(&key->cert->extensions) == 0)
1860                         printf("(none)\n");
1861                 else {
1862                         printf("\n");
1863                         show_options(&key->cert->extensions, v00, 0);
1864                 }
1865         }
1866         exit(0);
1867 }
1868
1869 static void
1870 usage(void)
1871 {
1872         fprintf(stderr, "usage: %s [options]\n", __progname);
1873         fprintf(stderr, "Options:\n");
1874         fprintf(stderr, "  -A          Generate non-existent host keys for all key types.\n");
1875         fprintf(stderr, "  -a trials   Number of trials for screening DH-GEX moduli.\n");
1876         fprintf(stderr, "  -B          Show bubblebabble digest of key file.\n");
1877         fprintf(stderr, "  -b bits     Number of bits in the key to create.\n");
1878         fprintf(stderr, "  -C comment  Provide new comment.\n");
1879         fprintf(stderr, "  -c          Change comment in private and public key files.\n");
1880 #ifdef ENABLE_PKCS11
1881         fprintf(stderr, "  -D pkcs11   Download public key from pkcs11 token.\n");
1882 #endif
1883         fprintf(stderr, "  -e          Export OpenSSH to foreign format key file.\n");
1884         fprintf(stderr, "  -F hostname Find hostname in known hosts file.\n");
1885         fprintf(stderr, "  -f filename Filename of the key file.\n");
1886         fprintf(stderr, "  -G file     Generate candidates for DH-GEX moduli.\n");
1887         fprintf(stderr, "  -g          Use generic DNS resource record format.\n");
1888         fprintf(stderr, "  -H          Hash names in known_hosts file.\n");
1889         fprintf(stderr, "  -h          Generate host certificate instead of a user certificate.\n");
1890         fprintf(stderr, "  -I key_id   Key identifier to include in certificate.\n");
1891         fprintf(stderr, "  -i          Import foreign format to OpenSSH key file.\n");
1892         fprintf(stderr, "  -J number   Screen this number of moduli lines.\n");
1893         fprintf(stderr, "  -j number   Start screening moduli at specified line.\n");
1894         fprintf(stderr, "  -K checkpt  Write checkpoints to this file.\n");
1895         fprintf(stderr, "  -L          Print the contents of a certificate.\n");
1896         fprintf(stderr, "  -l          Show fingerprint of key file.\n");
1897         fprintf(stderr, "  -M memory   Amount of memory (MB) to use for generating DH-GEX moduli.\n");
1898         fprintf(stderr, "  -m key_fmt  Conversion format for -e/-i (PEM|PKCS8|RFC4716).\n");
1899         fprintf(stderr, "  -N phrase   Provide new passphrase.\n");
1900         fprintf(stderr, "  -n name,... User/host principal names to include in certificate\n");
1901         fprintf(stderr, "  -O option   Specify a certificate option.\n");
1902         fprintf(stderr, "  -P phrase   Provide old passphrase.\n");
1903         fprintf(stderr, "  -p          Change passphrase of private key file.\n");
1904         fprintf(stderr, "  -q          Quiet.\n");
1905         fprintf(stderr, "  -R hostname Remove host from known_hosts file.\n");
1906         fprintf(stderr, "  -r hostname Print DNS resource record.\n");
1907         fprintf(stderr, "  -S start    Start point (hex) for generating DH-GEX moduli.\n");
1908         fprintf(stderr, "  -s ca_key   Certify keys with CA key.\n");
1909         fprintf(stderr, "  -T file     Screen candidates for DH-GEX moduli.\n");
1910         fprintf(stderr, "  -t type     Specify type of key to create.\n");
1911         fprintf(stderr, "  -V from:to  Specify certificate validity interval.\n");
1912         fprintf(stderr, "  -v          Verbose.\n");
1913         fprintf(stderr, "  -W gen      Generator to use for generating DH-GEX moduli.\n");
1914         fprintf(stderr, "  -y          Read private key file and print public key.\n");
1915         fprintf(stderr, "  -z serial   Specify a serial number.\n");
1916
1917         exit(1);
1918 }
1919
1920 /*
1921  * Main program for key management.
1922  */
1923 int
1924 main(int argc, char **argv)
1925 {
1926         char dotsshdir[MAXPATHLEN], comment[1024], *passphrase1, *passphrase2;
1927         char *checkpoint = NULL;
1928         char out_file[MAXPATHLEN], *rr_hostname = NULL;
1929         Key *private, *public;
1930         struct passwd *pw;
1931         struct stat st;
1932         int opt, type, fd;
1933         u_int32_t memory = 0, generator_wanted = 0, trials = 100;
1934         int do_gen_candidates = 0, do_screen_candidates = 0;
1935         int gen_all_hostkeys = 0;
1936         unsigned long start_lineno = 0, lines_to_process = 0;
1937         BIGNUM *start = NULL;
1938         FILE *f;
1939         const char *errstr;
1940
1941         extern int optind;
1942         extern char *optarg;
1943
1944         /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
1945         sanitise_stdfd();
1946
1947         __progname = ssh_get_progname(argv[0]);
1948
1949         OpenSSL_add_all_algorithms();
1950         log_init(argv[0], SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_USER, 1);
1951
1952         seed_rng();
1953
1954         /* we need this for the home * directory.  */
1955         pw = getpwuid(getuid());
1956         if (!pw) {
1957                 printf("You don't exist, go away!\n");
1958                 exit(1);
1959         }
1960         if (gethostname(hostname, sizeof(hostname)) < 0) {
1961                 perror("gethostname");
1962                 exit(1);
1963         }
1964
1965         while ((opt = getopt(argc, argv, "AegiqpclBHLhvxXyF:b:f:t:D:I:J:j:K:P:"
1966             "m:N:n:O:C:r:g:R:T:G:M:S:s:a:V:W:z")) != -1) {
1967                 switch (opt) {
1968                 case 'A':
1969                         gen_all_hostkeys = 1;
1970                         break;
1971                 case 'b':
1972                         bits = (u_int32_t)strtonum(optarg, 256, 32768, &errstr);
1973                         if (errstr)
1974                                 fatal("Bits has bad value %s (%s)",
1975                                         optarg, errstr);
1976                         break;
1977                 case 'F':
1978                         find_host = 1;
1979                         rr_hostname = optarg;
1980                         break;
1981                 case 'H':
1982                         hash_hosts = 1;
1983                         break;
1984                 case 'I':
1985                         cert_key_id = optarg;
1986                         break;
1987                 case 'J':
1988                         lines_to_process = strtoul(optarg, NULL, 10);
1989                         break;
1990                 case 'j':
1991                         start_lineno = strtoul(optarg, NULL, 10);
1992                         break;
1993                 case 'R':
1994                         delete_host = 1;
1995                         rr_hostname = optarg;
1996                         break;
1997                 case 'L':
1998                         show_cert = 1;
1999                         break;
2000                 case 'l':
2001                         print_fingerprint = 1;
2002                         break;
2003                 case 'B':
2004                         print_bubblebabble = 1;
2005                         break;
2006                 case 'm':
2007                         if (strcasecmp(optarg, "RFC4716") == 0 ||
2008                             strcasecmp(optarg, "ssh2") == 0) {
2009                                 convert_format = FMT_RFC4716;
2010                                 break;
2011                         }
2012                         if (strcasecmp(optarg, "PKCS8") == 0) {
2013                                 convert_format = FMT_PKCS8;
2014                                 break;
2015                         }
2016                         if (strcasecmp(optarg, "PEM") == 0) {
2017                                 convert_format = FMT_PEM;
2018                                 break;
2019                         }
2020                         fatal("Unsupported conversion format \"%s\"", optarg);
2021                 case 'n':
2022                         cert_principals = optarg;
2023                         break;
2024                 case 'p':
2025                         change_passphrase = 1;
2026                         break;
2027                 case 'c':
2028                         change_comment = 1;
2029                         break;
2030                 case 'f':
2031                         if (strlcpy(identity_file, optarg, sizeof(identity_file)) >=
2032                             sizeof(identity_file))
2033                                 fatal("Identity filename too long");
2034                         have_identity = 1;
2035                         break;
2036                 case 'g':
2037                         print_generic = 1;
2038                         break;
2039                 case 'P':
2040                         identity_passphrase = optarg;
2041                         break;
2042                 case 'N':
2043                         identity_new_passphrase = optarg;
2044                         break;
2045                 case 'O':
2046                         add_cert_option(optarg);
2047                         break;
2048                 case 'C':
2049                         identity_comment = optarg;
2050                         break;
2051                 case 'q':
2052                         quiet = 1;
2053                         break;
2054                 case 'e':
2055                 case 'x':
2056                         /* export key */
2057                         convert_to = 1;
2058                         break;
2059                 case 'h':
2060                         cert_key_type = SSH2_CERT_TYPE_HOST;
2061                         certflags_flags = 0;
2062                         break;
2063                 case 'i':
2064                 case 'X':
2065                         /* import key */
2066                         convert_from = 1;
2067                         break;
2068                 case 'y':
2069                         print_public = 1;
2070                         break;
2071                 case 's':
2072                         ca_key_path = optarg;
2073                         break;
2074                 case 't':
2075                         key_type_name = optarg;
2076                         break;
2077                 case 'D':
2078                         pkcs11provider = optarg;
2079                         break;
2080                 case 'v':
2081                         if (log_level == SYSLOG_LEVEL_INFO)
2082                                 log_level = SYSLOG_LEVEL_DEBUG1;
2083                         else {
2084                                 if (log_level >= SYSLOG_LEVEL_DEBUG1 &&
2085                                     log_level < SYSLOG_LEVEL_DEBUG3)
2086                                         log_level++;
2087                         }
2088                         break;
2089                 case 'r':
2090                         rr_hostname = optarg;
2091                         break;
2092                 case 'W':
2093                         generator_wanted = (u_int32_t)strtonum(optarg, 1,
2094                             UINT_MAX, &errstr);
2095                         if (errstr)
2096                                 fatal("Desired generator has bad value: %s (%s)",
2097                                         optarg, errstr);
2098                         break;
2099                 case 'a':
2100                         trials = (u_int32_t)strtonum(optarg, 1, UINT_MAX, &errstr);
2101                         if (errstr)
2102                                 fatal("Invalid number of trials: %s (%s)",
2103                                         optarg, errstr);
2104                         break;
2105                 case 'M':
2106                         memory = (u_int32_t)strtonum(optarg, 1, UINT_MAX, &errstr);
2107                         if (errstr)
2108                                 fatal("Memory limit is %s: %s", errstr, optarg);
2109                         break;
2110                 case 'G':
2111                         do_gen_candidates = 1;
2112                         if (strlcpy(out_file, optarg, sizeof(out_file)) >=
2113                             sizeof(out_file))
2114                                 fatal("Output filename too long");
2115                         break;
2116                 case 'T':
2117                         do_screen_candidates = 1;
2118                         if (strlcpy(out_file, optarg, sizeof(out_file)) >=
2119                             sizeof(out_file))
2120                                 fatal("Output filename too long");
2121                         break;
2122                 case 'K':
2123                         if (strlen(optarg) >= MAXPATHLEN)
2124                                 fatal("Checkpoint filename too long");
2125                         checkpoint = xstrdup(optarg);
2126                         break;
2127                 case 'S':
2128                         /* XXX - also compare length against bits */
2129                         if (BN_hex2bn(&start, optarg) == 0)
2130                                 fatal("Invalid start point.");
2131                         break;
2132                 case 'V':
2133                         parse_cert_times(optarg);
2134                         break;
2135                 case 'z':
2136                         cert_serial = strtonum(optarg, 0, LLONG_MAX, &errstr);
2137                         if (errstr)
2138                                 fatal("Invalid serial number: %s", errstr);
2139                         break;
2140                 case '?':
2141                 default:
2142                         usage();
2143                 }
2144         }
2145
2146         /* reinit */
2147         log_init(argv[0], log_level, SYSLOG_FACILITY_USER, 1);
2148
2149         argv += optind;
2150         argc -= optind;
2151
2152         if (ca_key_path != NULL) {
2153                 if (argc < 1) {
2154                         printf("Too few arguments.\n");
2155                         usage();
2156                 }
2157         } else if (argc > 0) {
2158                 printf("Too many arguments.\n");
2159                 usage();
2160         }
2161         if (change_passphrase && change_comment) {
2162                 printf("Can only have one of -p and -c.\n");
2163                 usage();
2164         }
2165         if (print_fingerprint && (delete_host || hash_hosts)) {
2166                 printf("Cannot use -l with -D or -R.\n");
2167                 usage();
2168         }
2169         if (ca_key_path != NULL) {
2170                 if (cert_key_id == NULL)
2171                         fatal("Must specify key id (-I) when certifying");
2172                 do_ca_sign(pw, argc, argv);
2173         }
2174         if (show_cert)
2175                 do_show_cert(pw);
2176         if (delete_host || hash_hosts || find_host)
2177                 do_known_hosts(pw, rr_hostname);
2178         if (print_fingerprint || print_bubblebabble)
2179                 do_fingerprint(pw);
2180         if (change_passphrase)
2181                 do_change_passphrase(pw);
2182         if (change_comment)
2183                 do_change_comment(pw);
2184         if (convert_to)
2185                 do_convert_to(pw);
2186         if (convert_from)
2187                 do_convert_from(pw);
2188         if (print_public)
2189                 do_print_public(pw);
2190         if (rr_hostname != NULL) {
2191                 unsigned int n = 0;
2192
2193                 if (have_identity) {
2194                         n = do_print_resource_record(pw,
2195                             identity_file, rr_hostname);
2196                         if (n == 0) {
2197                                 perror(identity_file);
2198                                 exit(1);
2199                         }
2200                         exit(0);
2201                 } else {
2202
2203                         n += do_print_resource_record(pw,
2204                             _PATH_HOST_RSA_KEY_FILE, rr_hostname);
2205                         n += do_print_resource_record(pw,
2206                             _PATH_HOST_DSA_KEY_FILE, rr_hostname);
2207                         n += do_print_resource_record(pw,
2208                             _PATH_HOST_ECDSA_KEY_FILE, rr_hostname);
2209
2210                         if (n == 0)
2211                                 fatal("no keys found.");
2212                         exit(0);
2213                 }
2214         }
2215         if (pkcs11provider != NULL)
2216                 do_download(pw);
2217
2218         if (do_gen_candidates) {
2219                 FILE *out = fopen(out_file, "w");
2220
2221                 if (out == NULL) {
2222                         error("Couldn't open modulus candidate file \"%s\": %s",
2223                             out_file, strerror(errno));
2224                         return (1);
2225                 }
2226                 if (bits == 0)
2227                         bits = DEFAULT_BITS;
2228                 if (gen_candidates(out, memory, bits, start) != 0)
2229                         fatal("modulus candidate generation failed");
2230
2231                 return (0);
2232         }
2233
2234         if (do_screen_candidates) {
2235                 FILE *in;
2236                 FILE *out = fopen(out_file, "w");
2237
2238                 if (have_identity && strcmp(identity_file, "-") != 0) {
2239                         if ((in = fopen(identity_file, "r")) == NULL) {
2240                                 fatal("Couldn't open modulus candidate "
2241                                     "file \"%s\": %s", identity_file,
2242                                     strerror(errno));
2243                         }
2244                 } else
2245                         in = stdin;
2246
2247                 if (out == NULL) {
2248                         fatal("Couldn't open moduli file \"%s\": %s",
2249                             out_file, strerror(errno));
2250                 }
2251                 if (prime_test(in, out, trials, generator_wanted, checkpoint,
2252                     start_lineno, lines_to_process) != 0)
2253                         fatal("modulus screening failed");
2254                 return (0);
2255         }
2256
2257         if (gen_all_hostkeys) {
2258                 do_gen_all_hostkeys(pw);
2259                 return (0);
2260         }
2261
2262         arc4random_stir();
2263
2264         if (key_type_name == NULL)
2265                 key_type_name = "rsa";
2266
2267         type = key_type_from_name(key_type_name);
2268         type_bits_valid(type, &bits);
2269
2270         if (!quiet)
2271                 printf("Generating public/private %s key pair.\n", key_type_name);
2272         private = key_generate(type, bits);
2273         if (private == NULL) {
2274                 fprintf(stderr, "key_generate failed\n");
2275                 exit(1);
2276         }
2277         public  = key_from_private(private);
2278
2279         if (!have_identity)
2280                 ask_filename(pw, "Enter file in which to save the key");
2281
2282         /* Create ~/.ssh directory if it doesn't already exist. */
2283         snprintf(dotsshdir, sizeof dotsshdir, "%s/%s",
2284             pw->pw_dir, _PATH_SSH_USER_DIR);
2285         if (strstr(identity_file, dotsshdir) != NULL) {
2286                 if (stat(dotsshdir, &st) < 0) {
2287                         if (errno != ENOENT) {
2288                                 error("Could not stat %s: %s", dotsshdir,
2289                                     strerror(errno));
2290                         } else if (mkdir(dotsshdir, 0700) < 0) {
2291                                 error("Could not create directory '%s': %s",
2292                                     dotsshdir, strerror(errno));
2293                         } else if (!quiet)
2294                                 printf("Created directory '%s'.\n", dotsshdir);
2295                 }
2296         }
2297         /* If the file already exists, ask the user to confirm. */
2298         if (stat(identity_file, &st) >= 0) {
2299                 char yesno[3];
2300                 printf("%s already exists.\n", identity_file);
2301                 printf("Overwrite (y/n)? ");
2302                 fflush(stdout);
2303                 if (fgets(yesno, sizeof(yesno), stdin) == NULL)
2304                         exit(1);
2305                 if (yesno[0] != 'y' && yesno[0] != 'Y')
2306                         exit(1);
2307         }
2308         /* Ask for a passphrase (twice). */
2309         if (identity_passphrase)
2310                 passphrase1 = xstrdup(identity_passphrase);
2311         else if (identity_new_passphrase)
2312                 passphrase1 = xstrdup(identity_new_passphrase);
2313         else {
2314 passphrase_again:
2315                 passphrase1 =
2316                         read_passphrase("Enter passphrase (empty for no "
2317                             "passphrase): ", RP_ALLOW_STDIN);
2318                 passphrase2 = read_passphrase("Enter same passphrase again: ",
2319                     RP_ALLOW_STDIN);
2320                 if (strcmp(passphrase1, passphrase2) != 0) {
2321                         /*
2322                          * The passphrases do not match.  Clear them and
2323                          * retry.
2324                          */
2325                         memset(passphrase1, 0, strlen(passphrase1));
2326                         memset(passphrase2, 0, strlen(passphrase2));
2327                         xfree(passphrase1);
2328                         xfree(passphrase2);
2329                         printf("Passphrases do not match.  Try again.\n");
2330                         goto passphrase_again;
2331                 }
2332                 /* Clear the other copy of the passphrase. */
2333                 memset(passphrase2, 0, strlen(passphrase2));
2334                 xfree(passphrase2);
2335         }
2336
2337         if (identity_comment) {
2338                 strlcpy(comment, identity_comment, sizeof(comment));
2339         } else {
2340                 /* Create default comment field for the passphrase. */
2341                 snprintf(comment, sizeof comment, "%s@%s", pw->pw_name, hostname);
2342         }
2343
2344         /* Save the key with the given passphrase and comment. */
2345         if (!key_save_private(private, identity_file, passphrase1, comment)) {
2346                 printf("Saving the key failed: %s.\n", identity_file);
2347                 memset(passphrase1, 0, strlen(passphrase1));
2348                 xfree(passphrase1);
2349                 exit(1);
2350         }
2351         /* Clear the passphrase. */
2352         memset(passphrase1, 0, strlen(passphrase1));
2353         xfree(passphrase1);
2354
2355         /* Clear the private key and the random number generator. */
2356         key_free(private);
2357         arc4random_stir();
2358
2359         if (!quiet)
2360                 printf("Your identification has been saved in %s.\n", identity_file);
2361
2362         strlcat(identity_file, ".pub", sizeof(identity_file));
2363         fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
2364         if (fd == -1) {
2365                 printf("Could not save your public key in %s\n", identity_file);
2366                 exit(1);
2367         }
2368         f = fdopen(fd, "w");
2369         if (f == NULL) {
2370                 printf("fdopen %s failed\n", identity_file);
2371                 exit(1);
2372         }
2373         if (!key_write(public, f))
2374                 fprintf(stderr, "write key failed\n");
2375         fprintf(f, " %s\n", comment);
2376         fclose(f);
2377
2378         if (!quiet) {
2379                 char *fp = key_fingerprint(public, SSH_FP_MD5, SSH_FP_HEX);
2380                 char *ra = key_fingerprint(public, SSH_FP_MD5,
2381                     SSH_FP_RANDOMART);
2382                 printf("Your public key has been saved in %s.\n",
2383                     identity_file);
2384                 printf("The key fingerprint is:\n");
2385                 printf("%s %s\n", fp, comment);
2386                 printf("The key's randomart image is:\n");
2387                 printf("%s\n", ra);
2388                 xfree(ra);
2389                 xfree(fp);
2390         }
2391
2392         key_free(public);
2393         exit(0);
2394 }