1 /* $OpenBSD: sshkey.c,v 1.112 2020/10/19 22:49:23 dtucker Exp $ */ 2 /* 3 * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved. 4 * Copyright (c) 2008 Alexander von Gernler. All rights reserved. 5 * Copyright (c) 2010,2011 Damien Miller. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #include <sys/types.h> 29 #include <netinet/in.h> 30 31 #ifdef WITH_OPENSSL 32 #include <openssl/evp.h> 33 #include <openssl/err.h> 34 #include <openssl/pem.h> 35 #endif 36 37 #include "crypto_api.h" 38 39 #include <errno.h> 40 #include <stdio.h> 41 #include <string.h> 42 #include <util.h> 43 #include <limits.h> 44 #include <resolv.h> 45 46 #include "ssh2.h" 47 #include "ssherr.h" 48 #include "misc.h" 49 #include "sshbuf.h" 50 #include "cipher.h" 51 #include "digest.h" 52 #define SSHKEY_INTERNAL 53 #include "sshkey.h" 54 #include "match.h" 55 #include "ssh-sk.h" 56 57 #ifdef WITH_XMSS 58 #include "sshkey-xmss.h" 59 #include "xmss_fast.h" 60 #endif 61 62 /* openssh private key file format */ 63 #define MARK_BEGIN "-----BEGIN OPENSSH PRIVATE KEY-----\n" 64 #define MARK_END "-----END OPENSSH PRIVATE KEY-----\n" 65 #define MARK_BEGIN_LEN (sizeof(MARK_BEGIN) - 1) 66 #define MARK_END_LEN (sizeof(MARK_END) - 1) 67 #define KDFNAME "bcrypt" 68 #define AUTH_MAGIC "openssh-key-v1" 69 #define SALT_LEN 16 70 #define DEFAULT_CIPHERNAME "aes256-ctr" 71 #define DEFAULT_ROUNDS 16 72 73 /* Version identification string for SSH v1 identity files. */ 74 #define LEGACY_BEGIN "SSH PRIVATE KEY FILE FORMAT 1.1\n" 75 76 /* 77 * Constants relating to "shielding" support; protection of keys expected 78 * to remain in memory for long durations 79 */ 80 #define SSHKEY_SHIELD_PREKEY_LEN (16 * 1024) 81 #define SSHKEY_SHIELD_CIPHER "aes256-ctr" /* XXX want AES-EME* */ 82 #define SSHKEY_SHIELD_PREKEY_HASH SSH_DIGEST_SHA512 83 84 int sshkey_private_serialize_opt(struct sshkey *key, 85 struct sshbuf *buf, enum sshkey_serialize_rep); 86 static int sshkey_from_blob_internal(struct sshbuf *buf, 87 struct sshkey **keyp, int allow_cert); 88 89 /* Supported key types */ 90 struct keytype { 91 const char *name; 92 const char *shortname; 93 const char *sigalg; 94 int type; 95 int nid; 96 int cert; 97 int sigonly; 98 }; 99 static const struct keytype keytypes[] = { 100 { "ssh-ed25519", "ED25519", NULL, KEY_ED25519, 0, 0, 0 }, 101 { "ssh-ed25519-cert-v01@openssh.com", "ED25519-CERT", NULL, 102 KEY_ED25519_CERT, 0, 1, 0 }, 103 { "sk-ssh-ed25519@openssh.com", "ED25519-SK", NULL, 104 KEY_ED25519_SK, 0, 0, 0 }, 105 { "sk-ssh-ed25519-cert-v01@openssh.com", "ED25519-SK-CERT", NULL, 106 KEY_ED25519_SK_CERT, 0, 1, 0 }, 107 #ifdef WITH_XMSS 108 { "ssh-xmss@openssh.com", "XMSS", NULL, KEY_XMSS, 0, 0, 0 }, 109 { "ssh-xmss-cert-v01@openssh.com", "XMSS-CERT", NULL, 110 KEY_XMSS_CERT, 0, 1, 0 }, 111 #endif /* WITH_XMSS */ 112 #ifdef WITH_OPENSSL 113 { "ssh-rsa", "RSA", NULL, KEY_RSA, 0, 0, 0 }, 114 { "rsa-sha2-256", "RSA", NULL, KEY_RSA, 0, 0, 1 }, 115 { "rsa-sha2-512", "RSA", NULL, KEY_RSA, 0, 0, 1 }, 116 { "ssh-dss", "DSA", NULL, KEY_DSA, 0, 0, 0 }, 117 { "ecdsa-sha2-nistp256", "ECDSA", NULL, 118 KEY_ECDSA, NID_X9_62_prime256v1, 0, 0 }, 119 { "ecdsa-sha2-nistp384", "ECDSA", NULL, 120 KEY_ECDSA, NID_secp384r1, 0, 0 }, 121 { "ecdsa-sha2-nistp521", "ECDSA", NULL, 122 KEY_ECDSA, NID_secp521r1, 0, 0 }, 123 { "sk-ecdsa-sha2-nistp256@openssh.com", "ECDSA-SK", NULL, 124 KEY_ECDSA_SK, NID_X9_62_prime256v1, 0, 0 }, 125 { "webauthn-sk-ecdsa-sha2-nistp256@openssh.com", "ECDSA-SK", NULL, 126 KEY_ECDSA_SK, NID_X9_62_prime256v1, 0, 1 }, 127 { "ssh-rsa-cert-v01@openssh.com", "RSA-CERT", NULL, 128 KEY_RSA_CERT, 0, 1, 0 }, 129 { "rsa-sha2-256-cert-v01@openssh.com", "RSA-CERT", 130 "rsa-sha2-256", KEY_RSA_CERT, 0, 1, 1 }, 131 { "rsa-sha2-512-cert-v01@openssh.com", "RSA-CERT", 132 "rsa-sha2-512", KEY_RSA_CERT, 0, 1, 1 }, 133 { "ssh-dss-cert-v01@openssh.com", "DSA-CERT", NULL, 134 KEY_DSA_CERT, 0, 1, 0 }, 135 { "ecdsa-sha2-nistp256-cert-v01@openssh.com", "ECDSA-CERT", NULL, 136 KEY_ECDSA_CERT, NID_X9_62_prime256v1, 1, 0 }, 137 { "ecdsa-sha2-nistp384-cert-v01@openssh.com", "ECDSA-CERT", NULL, 138 KEY_ECDSA_CERT, NID_secp384r1, 1, 0 }, 139 { "ecdsa-sha2-nistp521-cert-v01@openssh.com", "ECDSA-CERT", NULL, 140 KEY_ECDSA_CERT, NID_secp521r1, 1, 0 }, 141 { "sk-ecdsa-sha2-nistp256-cert-v01@openssh.com", "ECDSA-SK-CERT", NULL, 142 KEY_ECDSA_SK_CERT, NID_X9_62_prime256v1, 1, 0 }, 143 #endif /* WITH_OPENSSL */ 144 { NULL, NULL, NULL, -1, -1, 0, 0 } 145 }; 146 147 const char * 148 sshkey_type(const struct sshkey *k) 149 { 150 const struct keytype *kt; 151 152 for (kt = keytypes; kt->type != -1; kt++) { 153 if (kt->type == k->type) 154 return kt->shortname; 155 } 156 return "unknown"; 157 } 158 159 static const char * 160 sshkey_ssh_name_from_type_nid(int type, int nid) 161 { 162 const struct keytype *kt; 163 164 for (kt = keytypes; kt->type != -1; kt++) { 165 if (kt->type == type && (kt->nid == 0 || kt->nid == nid)) 166 return kt->name; 167 } 168 return "ssh-unknown"; 169 } 170 171 int 172 sshkey_type_is_cert(int type) 173 { 174 const struct keytype *kt; 175 176 for (kt = keytypes; kt->type != -1; kt++) { 177 if (kt->type == type) 178 return kt->cert; 179 } 180 return 0; 181 } 182 183 const char * 184 sshkey_ssh_name(const struct sshkey *k) 185 { 186 return sshkey_ssh_name_from_type_nid(k->type, k->ecdsa_nid); 187 } 188 189 const char * 190 sshkey_ssh_name_plain(const struct sshkey *k) 191 { 192 return sshkey_ssh_name_from_type_nid(sshkey_type_plain(k->type), 193 k->ecdsa_nid); 194 } 195 196 int 197 sshkey_type_from_name(const char *name) 198 { 199 const struct keytype *kt; 200 201 for (kt = keytypes; kt->type != -1; kt++) { 202 /* Only allow shortname matches for plain key types */ 203 if ((kt->name != NULL && strcmp(name, kt->name) == 0) || 204 (!kt->cert && strcasecmp(kt->shortname, name) == 0)) 205 return kt->type; 206 } 207 return KEY_UNSPEC; 208 } 209 210 static int 211 key_type_is_ecdsa_variant(int type) 212 { 213 switch (type) { 214 case KEY_ECDSA: 215 case KEY_ECDSA_CERT: 216 case KEY_ECDSA_SK: 217 case KEY_ECDSA_SK_CERT: 218 return 1; 219 } 220 return 0; 221 } 222 223 int 224 sshkey_ecdsa_nid_from_name(const char *name) 225 { 226 const struct keytype *kt; 227 228 for (kt = keytypes; kt->type != -1; kt++) { 229 if (!key_type_is_ecdsa_variant(kt->type)) 230 continue; 231 if (kt->name != NULL && strcmp(name, kt->name) == 0) 232 return kt->nid; 233 } 234 return -1; 235 } 236 237 char * 238 sshkey_alg_list(int certs_only, int plain_only, int include_sigonly, char sep) 239 { 240 char *tmp, *ret = NULL; 241 size_t nlen, rlen = 0; 242 const struct keytype *kt; 243 244 for (kt = keytypes; kt->type != -1; kt++) { 245 if (kt->name == NULL) 246 continue; 247 if (!include_sigonly && kt->sigonly) 248 continue; 249 if ((certs_only && !kt->cert) || (plain_only && kt->cert)) 250 continue; 251 if (ret != NULL) 252 ret[rlen++] = sep; 253 nlen = strlen(kt->name); 254 if ((tmp = realloc(ret, rlen + nlen + 2)) == NULL) { 255 free(ret); 256 return NULL; 257 } 258 ret = tmp; 259 memcpy(ret + rlen, kt->name, nlen + 1); 260 rlen += nlen; 261 } 262 return ret; 263 } 264 265 int 266 sshkey_names_valid2(const char *names, int allow_wildcard) 267 { 268 char *s, *cp, *p; 269 const struct keytype *kt; 270 int type; 271 272 if (names == NULL || strcmp(names, "") == 0) 273 return 0; 274 if ((s = cp = strdup(names)) == NULL) 275 return 0; 276 for ((p = strsep(&cp, ",")); p && *p != '\0'; 277 (p = strsep(&cp, ","))) { 278 type = sshkey_type_from_name(p); 279 if (type == KEY_UNSPEC) { 280 if (allow_wildcard) { 281 /* 282 * Try matching key types against the string. 283 * If any has a positive or negative match then 284 * the component is accepted. 285 */ 286 for (kt = keytypes; kt->type != -1; kt++) { 287 if (match_pattern_list(kt->name, 288 p, 0) != 0) 289 break; 290 } 291 if (kt->type != -1) 292 continue; 293 } 294 free(s); 295 return 0; 296 } 297 } 298 free(s); 299 return 1; 300 } 301 302 u_int 303 sshkey_size(const struct sshkey *k) 304 { 305 #ifdef WITH_OPENSSL 306 const BIGNUM *rsa_n, *dsa_p; 307 #endif /* WITH_OPENSSL */ 308 309 switch (k->type) { 310 #ifdef WITH_OPENSSL 311 case KEY_RSA: 312 case KEY_RSA_CERT: 313 if (k->rsa == NULL) 314 return 0; 315 RSA_get0_key(k->rsa, &rsa_n, NULL, NULL); 316 return BN_num_bits(rsa_n); 317 case KEY_DSA: 318 case KEY_DSA_CERT: 319 if (k->dsa == NULL) 320 return 0; 321 DSA_get0_pqg(k->dsa, &dsa_p, NULL, NULL); 322 return BN_num_bits(dsa_p); 323 case KEY_ECDSA: 324 case KEY_ECDSA_CERT: 325 case KEY_ECDSA_SK: 326 case KEY_ECDSA_SK_CERT: 327 return sshkey_curve_nid_to_bits(k->ecdsa_nid); 328 #endif /* WITH_OPENSSL */ 329 case KEY_ED25519: 330 case KEY_ED25519_CERT: 331 case KEY_ED25519_SK: 332 case KEY_ED25519_SK_CERT: 333 case KEY_XMSS: 334 case KEY_XMSS_CERT: 335 return 256; /* XXX */ 336 } 337 return 0; 338 } 339 340 static int 341 sshkey_type_is_valid_ca(int type) 342 { 343 switch (type) { 344 case KEY_RSA: 345 case KEY_DSA: 346 case KEY_ECDSA: 347 case KEY_ECDSA_SK: 348 case KEY_ED25519: 349 case KEY_ED25519_SK: 350 case KEY_XMSS: 351 return 1; 352 default: 353 return 0; 354 } 355 } 356 357 int 358 sshkey_is_cert(const struct sshkey *k) 359 { 360 if (k == NULL) 361 return 0; 362 return sshkey_type_is_cert(k->type); 363 } 364 365 int 366 sshkey_is_sk(const struct sshkey *k) 367 { 368 if (k == NULL) 369 return 0; 370 switch (sshkey_type_plain(k->type)) { 371 case KEY_ECDSA_SK: 372 case KEY_ED25519_SK: 373 return 1; 374 default: 375 return 0; 376 } 377 } 378 379 /* Return the cert-less equivalent to a certified key type */ 380 int 381 sshkey_type_plain(int type) 382 { 383 switch (type) { 384 case KEY_RSA_CERT: 385 return KEY_RSA; 386 case KEY_DSA_CERT: 387 return KEY_DSA; 388 case KEY_ECDSA_CERT: 389 return KEY_ECDSA; 390 case KEY_ECDSA_SK_CERT: 391 return KEY_ECDSA_SK; 392 case KEY_ED25519_CERT: 393 return KEY_ED25519; 394 case KEY_ED25519_SK_CERT: 395 return KEY_ED25519_SK; 396 case KEY_XMSS_CERT: 397 return KEY_XMSS; 398 default: 399 return type; 400 } 401 } 402 403 #ifdef WITH_OPENSSL 404 /* XXX: these are really begging for a table-driven approach */ 405 int 406 sshkey_curve_name_to_nid(const char *name) 407 { 408 if (strcmp(name, "nistp256") == 0) 409 return NID_X9_62_prime256v1; 410 else if (strcmp(name, "nistp384") == 0) 411 return NID_secp384r1; 412 else if (strcmp(name, "nistp521") == 0) 413 return NID_secp521r1; 414 else 415 return -1; 416 } 417 418 u_int 419 sshkey_curve_nid_to_bits(int nid) 420 { 421 switch (nid) { 422 case NID_X9_62_prime256v1: 423 return 256; 424 case NID_secp384r1: 425 return 384; 426 case NID_secp521r1: 427 return 521; 428 default: 429 return 0; 430 } 431 } 432 433 int 434 sshkey_ecdsa_bits_to_nid(int bits) 435 { 436 switch (bits) { 437 case 256: 438 return NID_X9_62_prime256v1; 439 case 384: 440 return NID_secp384r1; 441 case 521: 442 return NID_secp521r1; 443 default: 444 return -1; 445 } 446 } 447 448 const char * 449 sshkey_curve_nid_to_name(int nid) 450 { 451 switch (nid) { 452 case NID_X9_62_prime256v1: 453 return "nistp256"; 454 case NID_secp384r1: 455 return "nistp384"; 456 case NID_secp521r1: 457 return "nistp521"; 458 default: 459 return NULL; 460 } 461 } 462 463 int 464 sshkey_ec_nid_to_hash_alg(int nid) 465 { 466 int kbits = sshkey_curve_nid_to_bits(nid); 467 468 if (kbits <= 0) 469 return -1; 470 471 /* RFC5656 section 6.2.1 */ 472 if (kbits <= 256) 473 return SSH_DIGEST_SHA256; 474 else if (kbits <= 384) 475 return SSH_DIGEST_SHA384; 476 else 477 return SSH_DIGEST_SHA512; 478 } 479 #endif /* WITH_OPENSSL */ 480 481 static void 482 cert_free(struct sshkey_cert *cert) 483 { 484 u_int i; 485 486 if (cert == NULL) 487 return; 488 sshbuf_free(cert->certblob); 489 sshbuf_free(cert->critical); 490 sshbuf_free(cert->extensions); 491 free(cert->key_id); 492 for (i = 0; i < cert->nprincipals; i++) 493 free(cert->principals[i]); 494 free(cert->principals); 495 sshkey_free(cert->signature_key); 496 free(cert->signature_type); 497 freezero(cert, sizeof(*cert)); 498 } 499 500 static struct sshkey_cert * 501 cert_new(void) 502 { 503 struct sshkey_cert *cert; 504 505 if ((cert = calloc(1, sizeof(*cert))) == NULL) 506 return NULL; 507 if ((cert->certblob = sshbuf_new()) == NULL || 508 (cert->critical = sshbuf_new()) == NULL || 509 (cert->extensions = sshbuf_new()) == NULL) { 510 cert_free(cert); 511 return NULL; 512 } 513 cert->key_id = NULL; 514 cert->principals = NULL; 515 cert->signature_key = NULL; 516 cert->signature_type = NULL; 517 return cert; 518 } 519 520 struct sshkey * 521 sshkey_new(int type) 522 { 523 struct sshkey *k; 524 #ifdef WITH_OPENSSL 525 RSA *rsa; 526 DSA *dsa; 527 #endif /* WITH_OPENSSL */ 528 529 if ((k = calloc(1, sizeof(*k))) == NULL) 530 return NULL; 531 k->type = type; 532 k->ecdsa = NULL; 533 k->ecdsa_nid = -1; 534 k->dsa = NULL; 535 k->rsa = NULL; 536 k->cert = NULL; 537 k->ed25519_sk = NULL; 538 k->ed25519_pk = NULL; 539 k->xmss_sk = NULL; 540 k->xmss_pk = NULL; 541 switch (k->type) { 542 #ifdef WITH_OPENSSL 543 case KEY_RSA: 544 case KEY_RSA_CERT: 545 if ((rsa = RSA_new()) == NULL) { 546 free(k); 547 return NULL; 548 } 549 k->rsa = rsa; 550 break; 551 case KEY_DSA: 552 case KEY_DSA_CERT: 553 if ((dsa = DSA_new()) == NULL) { 554 free(k); 555 return NULL; 556 } 557 k->dsa = dsa; 558 break; 559 case KEY_ECDSA: 560 case KEY_ECDSA_CERT: 561 case KEY_ECDSA_SK: 562 case KEY_ECDSA_SK_CERT: 563 /* Cannot do anything until we know the group */ 564 break; 565 #endif /* WITH_OPENSSL */ 566 case KEY_ED25519: 567 case KEY_ED25519_CERT: 568 case KEY_ED25519_SK: 569 case KEY_ED25519_SK_CERT: 570 case KEY_XMSS: 571 case KEY_XMSS_CERT: 572 /* no need to prealloc */ 573 break; 574 case KEY_UNSPEC: 575 break; 576 default: 577 free(k); 578 return NULL; 579 } 580 581 if (sshkey_is_cert(k)) { 582 if ((k->cert = cert_new()) == NULL) { 583 sshkey_free(k); 584 return NULL; 585 } 586 } 587 588 return k; 589 } 590 591 void 592 sshkey_free(struct sshkey *k) 593 { 594 if (k == NULL) 595 return; 596 switch (k->type) { 597 #ifdef WITH_OPENSSL 598 case KEY_RSA: 599 case KEY_RSA_CERT: 600 RSA_free(k->rsa); 601 k->rsa = NULL; 602 break; 603 case KEY_DSA: 604 case KEY_DSA_CERT: 605 DSA_free(k->dsa); 606 k->dsa = NULL; 607 break; 608 case KEY_ECDSA_SK: 609 case KEY_ECDSA_SK_CERT: 610 free(k->sk_application); 611 sshbuf_free(k->sk_key_handle); 612 sshbuf_free(k->sk_reserved); 613 /* FALLTHROUGH */ 614 case KEY_ECDSA: 615 case KEY_ECDSA_CERT: 616 EC_KEY_free(k->ecdsa); 617 k->ecdsa = NULL; 618 break; 619 #endif /* WITH_OPENSSL */ 620 case KEY_ED25519_SK: 621 case KEY_ED25519_SK_CERT: 622 free(k->sk_application); 623 sshbuf_free(k->sk_key_handle); 624 sshbuf_free(k->sk_reserved); 625 /* FALLTHROUGH */ 626 case KEY_ED25519: 627 case KEY_ED25519_CERT: 628 freezero(k->ed25519_pk, ED25519_PK_SZ); 629 k->ed25519_pk = NULL; 630 freezero(k->ed25519_sk, ED25519_SK_SZ); 631 k->ed25519_sk = NULL; 632 break; 633 #ifdef WITH_XMSS 634 case KEY_XMSS: 635 case KEY_XMSS_CERT: 636 freezero(k->xmss_pk, sshkey_xmss_pklen(k)); 637 k->xmss_pk = NULL; 638 freezero(k->xmss_sk, sshkey_xmss_sklen(k)); 639 k->xmss_sk = NULL; 640 sshkey_xmss_free_state(k); 641 free(k->xmss_name); 642 k->xmss_name = NULL; 643 free(k->xmss_filename); 644 k->xmss_filename = NULL; 645 break; 646 #endif /* WITH_XMSS */ 647 case KEY_UNSPEC: 648 break; 649 default: 650 break; 651 } 652 if (sshkey_is_cert(k)) 653 cert_free(k->cert); 654 freezero(k->shielded_private, k->shielded_len); 655 freezero(k->shield_prekey, k->shield_prekey_len); 656 freezero(k, sizeof(*k)); 657 } 658 659 static int 660 cert_compare(struct sshkey_cert *a, struct sshkey_cert *b) 661 { 662 if (a == NULL && b == NULL) 663 return 1; 664 if (a == NULL || b == NULL) 665 return 0; 666 if (sshbuf_len(a->certblob) != sshbuf_len(b->certblob)) 667 return 0; 668 if (timingsafe_bcmp(sshbuf_ptr(a->certblob), sshbuf_ptr(b->certblob), 669 sshbuf_len(a->certblob)) != 0) 670 return 0; 671 return 1; 672 } 673 674 /* 675 * Compare public portions of key only, allowing comparisons between 676 * certificates and plain keys too. 677 */ 678 int 679 sshkey_equal_public(const struct sshkey *a, const struct sshkey *b) 680 { 681 #ifdef WITH_OPENSSL 682 const BIGNUM *rsa_e_a, *rsa_n_a; 683 const BIGNUM *rsa_e_b, *rsa_n_b; 684 const BIGNUM *dsa_p_a, *dsa_q_a, *dsa_g_a, *dsa_pub_key_a; 685 const BIGNUM *dsa_p_b, *dsa_q_b, *dsa_g_b, *dsa_pub_key_b; 686 #endif /* WITH_OPENSSL */ 687 688 if (a == NULL || b == NULL || 689 sshkey_type_plain(a->type) != sshkey_type_plain(b->type)) 690 return 0; 691 692 switch (a->type) { 693 #ifdef WITH_OPENSSL 694 case KEY_RSA_CERT: 695 case KEY_RSA: 696 if (a->rsa == NULL || b->rsa == NULL) 697 return 0; 698 RSA_get0_key(a->rsa, &rsa_n_a, &rsa_e_a, NULL); 699 RSA_get0_key(b->rsa, &rsa_n_b, &rsa_e_b, NULL); 700 return BN_cmp(rsa_e_a, rsa_e_b) == 0 && 701 BN_cmp(rsa_n_a, rsa_n_b) == 0; 702 case KEY_DSA_CERT: 703 case KEY_DSA: 704 if (a->dsa == NULL || b->dsa == NULL) 705 return 0; 706 DSA_get0_pqg(a->dsa, &dsa_p_a, &dsa_q_a, &dsa_g_a); 707 DSA_get0_pqg(b->dsa, &dsa_p_b, &dsa_q_b, &dsa_g_b); 708 DSA_get0_key(a->dsa, &dsa_pub_key_a, NULL); 709 DSA_get0_key(b->dsa, &dsa_pub_key_b, NULL); 710 return BN_cmp(dsa_p_a, dsa_p_b) == 0 && 711 BN_cmp(dsa_q_a, dsa_q_b) == 0 && 712 BN_cmp(dsa_g_a, dsa_g_b) == 0 && 713 BN_cmp(dsa_pub_key_a, dsa_pub_key_b) == 0; 714 case KEY_ECDSA_SK: 715 case KEY_ECDSA_SK_CERT: 716 if (a->sk_application == NULL || b->sk_application == NULL) 717 return 0; 718 if (strcmp(a->sk_application, b->sk_application) != 0) 719 return 0; 720 /* FALLTHROUGH */ 721 case KEY_ECDSA_CERT: 722 case KEY_ECDSA: 723 if (a->ecdsa == NULL || b->ecdsa == NULL || 724 EC_KEY_get0_public_key(a->ecdsa) == NULL || 725 EC_KEY_get0_public_key(b->ecdsa) == NULL) 726 return 0; 727 if (EC_GROUP_cmp(EC_KEY_get0_group(a->ecdsa), 728 EC_KEY_get0_group(b->ecdsa), NULL) != 0 || 729 EC_POINT_cmp(EC_KEY_get0_group(a->ecdsa), 730 EC_KEY_get0_public_key(a->ecdsa), 731 EC_KEY_get0_public_key(b->ecdsa), NULL) != 0) 732 return 0; 733 return 1; 734 #endif /* WITH_OPENSSL */ 735 case KEY_ED25519_SK: 736 case KEY_ED25519_SK_CERT: 737 if (a->sk_application == NULL || b->sk_application == NULL) 738 return 0; 739 if (strcmp(a->sk_application, b->sk_application) != 0) 740 return 0; 741 /* FALLTHROUGH */ 742 case KEY_ED25519: 743 case KEY_ED25519_CERT: 744 return a->ed25519_pk != NULL && b->ed25519_pk != NULL && 745 memcmp(a->ed25519_pk, b->ed25519_pk, ED25519_PK_SZ) == 0; 746 #ifdef WITH_XMSS 747 case KEY_XMSS: 748 case KEY_XMSS_CERT: 749 return a->xmss_pk != NULL && b->xmss_pk != NULL && 750 sshkey_xmss_pklen(a) == sshkey_xmss_pklen(b) && 751 memcmp(a->xmss_pk, b->xmss_pk, sshkey_xmss_pklen(a)) == 0; 752 #endif /* WITH_XMSS */ 753 default: 754 return 0; 755 } 756 /* NOTREACHED */ 757 } 758 759 int 760 sshkey_equal(const struct sshkey *a, const struct sshkey *b) 761 { 762 if (a == NULL || b == NULL || a->type != b->type) 763 return 0; 764 if (sshkey_is_cert(a)) { 765 if (!cert_compare(a->cert, b->cert)) 766 return 0; 767 } 768 return sshkey_equal_public(a, b); 769 } 770 771 static int 772 to_blob_buf(const struct sshkey *key, struct sshbuf *b, int force_plain, 773 enum sshkey_serialize_rep opts) 774 { 775 int type, ret = SSH_ERR_INTERNAL_ERROR; 776 const char *typename; 777 #ifdef WITH_OPENSSL 778 const BIGNUM *rsa_n, *rsa_e, *dsa_p, *dsa_q, *dsa_g, *dsa_pub_key; 779 #endif /* WITH_OPENSSL */ 780 781 if (key == NULL) 782 return SSH_ERR_INVALID_ARGUMENT; 783 784 if (sshkey_is_cert(key)) { 785 if (key->cert == NULL) 786 return SSH_ERR_EXPECTED_CERT; 787 if (sshbuf_len(key->cert->certblob) == 0) 788 return SSH_ERR_KEY_LACKS_CERTBLOB; 789 } 790 type = force_plain ? sshkey_type_plain(key->type) : key->type; 791 typename = sshkey_ssh_name_from_type_nid(type, key->ecdsa_nid); 792 793 switch (type) { 794 #ifdef WITH_OPENSSL 795 case KEY_DSA_CERT: 796 case KEY_ECDSA_CERT: 797 case KEY_ECDSA_SK_CERT: 798 case KEY_RSA_CERT: 799 #endif /* WITH_OPENSSL */ 800 case KEY_ED25519_CERT: 801 case KEY_ED25519_SK_CERT: 802 #ifdef WITH_XMSS 803 case KEY_XMSS_CERT: 804 #endif /* WITH_XMSS */ 805 /* Use the existing blob */ 806 /* XXX modified flag? */ 807 if ((ret = sshbuf_putb(b, key->cert->certblob)) != 0) 808 return ret; 809 break; 810 #ifdef WITH_OPENSSL 811 case KEY_DSA: 812 if (key->dsa == NULL) 813 return SSH_ERR_INVALID_ARGUMENT; 814 DSA_get0_pqg(key->dsa, &dsa_p, &dsa_q, &dsa_g); 815 DSA_get0_key(key->dsa, &dsa_pub_key, NULL); 816 if ((ret = sshbuf_put_cstring(b, typename)) != 0 || 817 (ret = sshbuf_put_bignum2(b, dsa_p)) != 0 || 818 (ret = sshbuf_put_bignum2(b, dsa_q)) != 0 || 819 (ret = sshbuf_put_bignum2(b, dsa_g)) != 0 || 820 (ret = sshbuf_put_bignum2(b, dsa_pub_key)) != 0) 821 return ret; 822 break; 823 case KEY_ECDSA: 824 case KEY_ECDSA_SK: 825 if (key->ecdsa == NULL) 826 return SSH_ERR_INVALID_ARGUMENT; 827 if ((ret = sshbuf_put_cstring(b, typename)) != 0 || 828 (ret = sshbuf_put_cstring(b, 829 sshkey_curve_nid_to_name(key->ecdsa_nid))) != 0 || 830 (ret = sshbuf_put_eckey(b, key->ecdsa)) != 0) 831 return ret; 832 if (type == KEY_ECDSA_SK) { 833 if ((ret = sshbuf_put_cstring(b, 834 key->sk_application)) != 0) 835 return ret; 836 } 837 break; 838 case KEY_RSA: 839 if (key->rsa == NULL) 840 return SSH_ERR_INVALID_ARGUMENT; 841 RSA_get0_key(key->rsa, &rsa_n, &rsa_e, NULL); 842 if ((ret = sshbuf_put_cstring(b, typename)) != 0 || 843 (ret = sshbuf_put_bignum2(b, rsa_e)) != 0 || 844 (ret = sshbuf_put_bignum2(b, rsa_n)) != 0) 845 return ret; 846 break; 847 #endif /* WITH_OPENSSL */ 848 case KEY_ED25519: 849 case KEY_ED25519_SK: 850 if (key->ed25519_pk == NULL) 851 return SSH_ERR_INVALID_ARGUMENT; 852 if ((ret = sshbuf_put_cstring(b, typename)) != 0 || 853 (ret = sshbuf_put_string(b, 854 key->ed25519_pk, ED25519_PK_SZ)) != 0) 855 return ret; 856 if (type == KEY_ED25519_SK) { 857 if ((ret = sshbuf_put_cstring(b, 858 key->sk_application)) != 0) 859 return ret; 860 } 861 break; 862 #ifdef WITH_XMSS 863 case KEY_XMSS: 864 if (key->xmss_name == NULL || key->xmss_pk == NULL || 865 sshkey_xmss_pklen(key) == 0) 866 return SSH_ERR_INVALID_ARGUMENT; 867 if ((ret = sshbuf_put_cstring(b, typename)) != 0 || 868 (ret = sshbuf_put_cstring(b, key->xmss_name)) != 0 || 869 (ret = sshbuf_put_string(b, 870 key->xmss_pk, sshkey_xmss_pklen(key))) != 0 || 871 (ret = sshkey_xmss_serialize_pk_info(key, b, opts)) != 0) 872 return ret; 873 break; 874 #endif /* WITH_XMSS */ 875 default: 876 return SSH_ERR_KEY_TYPE_UNKNOWN; 877 } 878 return 0; 879 } 880 881 int 882 sshkey_putb(const struct sshkey *key, struct sshbuf *b) 883 { 884 return to_blob_buf(key, b, 0, SSHKEY_SERIALIZE_DEFAULT); 885 } 886 887 int 888 sshkey_puts_opts(const struct sshkey *key, struct sshbuf *b, 889 enum sshkey_serialize_rep opts) 890 { 891 struct sshbuf *tmp; 892 int r; 893 894 if ((tmp = sshbuf_new()) == NULL) 895 return SSH_ERR_ALLOC_FAIL; 896 r = to_blob_buf(key, tmp, 0, opts); 897 if (r == 0) 898 r = sshbuf_put_stringb(b, tmp); 899 sshbuf_free(tmp); 900 return r; 901 } 902 903 int 904 sshkey_puts(const struct sshkey *key, struct sshbuf *b) 905 { 906 return sshkey_puts_opts(key, b, SSHKEY_SERIALIZE_DEFAULT); 907 } 908 909 int 910 sshkey_putb_plain(const struct sshkey *key, struct sshbuf *b) 911 { 912 return to_blob_buf(key, b, 1, SSHKEY_SERIALIZE_DEFAULT); 913 } 914 915 static int 916 to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp, int force_plain, 917 enum sshkey_serialize_rep opts) 918 { 919 int ret = SSH_ERR_INTERNAL_ERROR; 920 size_t len; 921 struct sshbuf *b = NULL; 922 923 if (lenp != NULL) 924 *lenp = 0; 925 if (blobp != NULL) 926 *blobp = NULL; 927 if ((b = sshbuf_new()) == NULL) 928 return SSH_ERR_ALLOC_FAIL; 929 if ((ret = to_blob_buf(key, b, force_plain, opts)) != 0) 930 goto out; 931 len = sshbuf_len(b); 932 if (lenp != NULL) 933 *lenp = len; 934 if (blobp != NULL) { 935 if ((*blobp = malloc(len)) == NULL) { 936 ret = SSH_ERR_ALLOC_FAIL; 937 goto out; 938 } 939 memcpy(*blobp, sshbuf_ptr(b), len); 940 } 941 ret = 0; 942 out: 943 sshbuf_free(b); 944 return ret; 945 } 946 947 int 948 sshkey_to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp) 949 { 950 return to_blob(key, blobp, lenp, 0, SSHKEY_SERIALIZE_DEFAULT); 951 } 952 953 int 954 sshkey_plain_to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp) 955 { 956 return to_blob(key, blobp, lenp, 1, SSHKEY_SERIALIZE_DEFAULT); 957 } 958 959 int 960 sshkey_fingerprint_raw(const struct sshkey *k, int dgst_alg, 961 u_char **retp, size_t *lenp) 962 { 963 u_char *blob = NULL, *ret = NULL; 964 size_t blob_len = 0; 965 int r = SSH_ERR_INTERNAL_ERROR; 966 967 if (retp != NULL) 968 *retp = NULL; 969 if (lenp != NULL) 970 *lenp = 0; 971 if (ssh_digest_bytes(dgst_alg) == 0) { 972 r = SSH_ERR_INVALID_ARGUMENT; 973 goto out; 974 } 975 if ((r = to_blob(k, &blob, &blob_len, 1, SSHKEY_SERIALIZE_DEFAULT)) 976 != 0) 977 goto out; 978 if ((ret = calloc(1, SSH_DIGEST_MAX_LENGTH)) == NULL) { 979 r = SSH_ERR_ALLOC_FAIL; 980 goto out; 981 } 982 if ((r = ssh_digest_memory(dgst_alg, blob, blob_len, 983 ret, SSH_DIGEST_MAX_LENGTH)) != 0) 984 goto out; 985 /* success */ 986 if (retp != NULL) { 987 *retp = ret; 988 ret = NULL; 989 } 990 if (lenp != NULL) 991 *lenp = ssh_digest_bytes(dgst_alg); 992 r = 0; 993 out: 994 free(ret); 995 if (blob != NULL) 996 freezero(blob, blob_len); 997 return r; 998 } 999 1000 static char * 1001 fingerprint_b64(const char *alg, u_char *dgst_raw, size_t dgst_raw_len) 1002 { 1003 char *ret; 1004 size_t plen = strlen(alg) + 1; 1005 size_t rlen = ((dgst_raw_len + 2) / 3) * 4 + plen + 1; 1006 1007 if (dgst_raw_len > 65536 || (ret = calloc(1, rlen)) == NULL) 1008 return NULL; 1009 strlcpy(ret, alg, rlen); 1010 strlcat(ret, ":", rlen); 1011 if (dgst_raw_len == 0) 1012 return ret; 1013 if (b64_ntop(dgst_raw, dgst_raw_len, ret + plen, rlen - plen) == -1) { 1014 freezero(ret, rlen); 1015 return NULL; 1016 } 1017 /* Trim padding characters from end */ 1018 ret[strcspn(ret, "=")] = '\0'; 1019 return ret; 1020 } 1021 1022 static char * 1023 fingerprint_hex(const char *alg, u_char *dgst_raw, size_t dgst_raw_len) 1024 { 1025 char *retval, hex[5]; 1026 size_t i, rlen = dgst_raw_len * 3 + strlen(alg) + 2; 1027 1028 if (dgst_raw_len > 65536 || (retval = calloc(1, rlen)) == NULL) 1029 return NULL; 1030 strlcpy(retval, alg, rlen); 1031 strlcat(retval, ":", rlen); 1032 for (i = 0; i < dgst_raw_len; i++) { 1033 snprintf(hex, sizeof(hex), "%s%02x", 1034 i > 0 ? ":" : "", dgst_raw[i]); 1035 strlcat(retval, hex, rlen); 1036 } 1037 return retval; 1038 } 1039 1040 static char * 1041 fingerprint_bubblebabble(u_char *dgst_raw, size_t dgst_raw_len) 1042 { 1043 char vowels[] = { 'a', 'e', 'i', 'o', 'u', 'y' }; 1044 char consonants[] = { 'b', 'c', 'd', 'f', 'g', 'h', 'k', 'l', 'm', 1045 'n', 'p', 'r', 's', 't', 'v', 'z', 'x' }; 1046 u_int i, j = 0, rounds, seed = 1; 1047 char *retval; 1048 1049 rounds = (dgst_raw_len / 2) + 1; 1050 if ((retval = calloc(rounds, 6)) == NULL) 1051 return NULL; 1052 retval[j++] = 'x'; 1053 for (i = 0; i < rounds; i++) { 1054 u_int idx0, idx1, idx2, idx3, idx4; 1055 if ((i + 1 < rounds) || (dgst_raw_len % 2 != 0)) { 1056 idx0 = (((((u_int)(dgst_raw[2 * i])) >> 6) & 3) + 1057 seed) % 6; 1058 idx1 = (((u_int)(dgst_raw[2 * i])) >> 2) & 15; 1059 idx2 = ((((u_int)(dgst_raw[2 * i])) & 3) + 1060 (seed / 6)) % 6; 1061 retval[j++] = vowels[idx0]; 1062 retval[j++] = consonants[idx1]; 1063 retval[j++] = vowels[idx2]; 1064 if ((i + 1) < rounds) { 1065 idx3 = (((u_int)(dgst_raw[(2 * i) + 1])) >> 4) & 15; 1066 idx4 = (((u_int)(dgst_raw[(2 * i) + 1]))) & 15; 1067 retval[j++] = consonants[idx3]; 1068 retval[j++] = '-'; 1069 retval[j++] = consonants[idx4]; 1070 seed = ((seed * 5) + 1071 ((((u_int)(dgst_raw[2 * i])) * 7) + 1072 ((u_int)(dgst_raw[(2 * i) + 1])))) % 36; 1073 } 1074 } else { 1075 idx0 = seed % 6; 1076 idx1 = 16; 1077 idx2 = seed / 6; 1078 retval[j++] = vowels[idx0]; 1079 retval[j++] = consonants[idx1]; 1080 retval[j++] = vowels[idx2]; 1081 } 1082 } 1083 retval[j++] = 'x'; 1084 retval[j++] = '\0'; 1085 return retval; 1086 } 1087 1088 /* 1089 * Draw an ASCII-Art representing the fingerprint so human brain can 1090 * profit from its built-in pattern recognition ability. 1091 * This technique is called "random art" and can be found in some 1092 * scientific publications like this original paper: 1093 * 1094 * "Hash Visualization: a New Technique to improve Real-World Security", 1095 * Perrig A. and Song D., 1999, International Workshop on Cryptographic 1096 * Techniques and E-Commerce (CrypTEC '99) 1097 * sparrow.ece.cmu.edu/~adrian/projects/validation/validation.pdf 1098 * 1099 * The subject came up in a talk by Dan Kaminsky, too. 1100 * 1101 * If you see the picture is different, the key is different. 1102 * If the picture looks the same, you still know nothing. 1103 * 1104 * The algorithm used here is a worm crawling over a discrete plane, 1105 * leaving a trace (augmenting the field) everywhere it goes. 1106 * Movement is taken from dgst_raw 2bit-wise. Bumping into walls 1107 * makes the respective movement vector be ignored for this turn. 1108 * Graphs are not unambiguous, because circles in graphs can be 1109 * walked in either direction. 1110 */ 1111 1112 /* 1113 * Field sizes for the random art. Have to be odd, so the starting point 1114 * can be in the exact middle of the picture, and FLDBASE should be >=8 . 1115 * Else pictures would be too dense, and drawing the frame would 1116 * fail, too, because the key type would not fit in anymore. 1117 */ 1118 #define FLDBASE 8 1119 #define FLDSIZE_Y (FLDBASE + 1) 1120 #define FLDSIZE_X (FLDBASE * 2 + 1) 1121 static char * 1122 fingerprint_randomart(const char *alg, u_char *dgst_raw, size_t dgst_raw_len, 1123 const struct sshkey *k) 1124 { 1125 /* 1126 * Chars to be used after each other every time the worm 1127 * intersects with itself. Matter of taste. 1128 */ 1129 char *augmentation_string = " .o+=*BOX@%&#/^SE"; 1130 char *retval, *p, title[FLDSIZE_X], hash[FLDSIZE_X]; 1131 u_char field[FLDSIZE_X][FLDSIZE_Y]; 1132 size_t i, tlen, hlen; 1133 u_int b; 1134 int x, y, r; 1135 size_t len = strlen(augmentation_string) - 1; 1136 1137 if ((retval = calloc((FLDSIZE_X + 3), (FLDSIZE_Y + 2))) == NULL) 1138 return NULL; 1139 1140 /* initialize field */ 1141 memset(field, 0, FLDSIZE_X * FLDSIZE_Y * sizeof(char)); 1142 x = FLDSIZE_X / 2; 1143 y = FLDSIZE_Y / 2; 1144 1145 /* process raw key */ 1146 for (i = 0; i < dgst_raw_len; i++) { 1147 int input; 1148 /* each byte conveys four 2-bit move commands */ 1149 input = dgst_raw[i]; 1150 for (b = 0; b < 4; b++) { 1151 /* evaluate 2 bit, rest is shifted later */ 1152 x += (input & 0x1) ? 1 : -1; 1153 y += (input & 0x2) ? 1 : -1; 1154 1155 /* assure we are still in bounds */ 1156 x = MAXIMUM(x, 0); 1157 y = MAXIMUM(y, 0); 1158 x = MINIMUM(x, FLDSIZE_X - 1); 1159 y = MINIMUM(y, FLDSIZE_Y - 1); 1160 1161 /* augment the field */ 1162 if (field[x][y] < len - 2) 1163 field[x][y]++; 1164 input = input >> 2; 1165 } 1166 } 1167 1168 /* mark starting point and end point*/ 1169 field[FLDSIZE_X / 2][FLDSIZE_Y / 2] = len - 1; 1170 field[x][y] = len; 1171 1172 /* assemble title */ 1173 r = snprintf(title, sizeof(title), "[%s %u]", 1174 sshkey_type(k), sshkey_size(k)); 1175 /* If [type size] won't fit, then try [type]; fits "[ED25519-CERT]" */ 1176 if (r < 0 || r > (int)sizeof(title)) 1177 r = snprintf(title, sizeof(title), "[%s]", sshkey_type(k)); 1178 tlen = (r <= 0) ? 0 : strlen(title); 1179 1180 /* assemble hash ID. */ 1181 r = snprintf(hash, sizeof(hash), "[%s]", alg); 1182 hlen = (r <= 0) ? 0 : strlen(hash); 1183 1184 /* output upper border */ 1185 p = retval; 1186 *p++ = '+'; 1187 for (i = 0; i < (FLDSIZE_X - tlen) / 2; i++) 1188 *p++ = '-'; 1189 memcpy(p, title, tlen); 1190 p += tlen; 1191 for (i += tlen; i < FLDSIZE_X; i++) 1192 *p++ = '-'; 1193 *p++ = '+'; 1194 *p++ = '\n'; 1195 1196 /* output content */ 1197 for (y = 0; y < FLDSIZE_Y; y++) { 1198 *p++ = '|'; 1199 for (x = 0; x < FLDSIZE_X; x++) 1200 *p++ = augmentation_string[MINIMUM(field[x][y], len)]; 1201 *p++ = '|'; 1202 *p++ = '\n'; 1203 } 1204 1205 /* output lower border */ 1206 *p++ = '+'; 1207 for (i = 0; i < (FLDSIZE_X - hlen) / 2; i++) 1208 *p++ = '-'; 1209 memcpy(p, hash, hlen); 1210 p += hlen; 1211 for (i += hlen; i < FLDSIZE_X; i++) 1212 *p++ = '-'; 1213 *p++ = '+'; 1214 1215 return retval; 1216 } 1217 1218 char * 1219 sshkey_fingerprint(const struct sshkey *k, int dgst_alg, 1220 enum sshkey_fp_rep dgst_rep) 1221 { 1222 char *retval = NULL; 1223 u_char *dgst_raw; 1224 size_t dgst_raw_len; 1225 1226 if (sshkey_fingerprint_raw(k, dgst_alg, &dgst_raw, &dgst_raw_len) != 0) 1227 return NULL; 1228 switch (dgst_rep) { 1229 case SSH_FP_DEFAULT: 1230 if (dgst_alg == SSH_DIGEST_MD5) { 1231 retval = fingerprint_hex(ssh_digest_alg_name(dgst_alg), 1232 dgst_raw, dgst_raw_len); 1233 } else { 1234 retval = fingerprint_b64(ssh_digest_alg_name(dgst_alg), 1235 dgst_raw, dgst_raw_len); 1236 } 1237 break; 1238 case SSH_FP_HEX: 1239 retval = fingerprint_hex(ssh_digest_alg_name(dgst_alg), 1240 dgst_raw, dgst_raw_len); 1241 break; 1242 case SSH_FP_BASE64: 1243 retval = fingerprint_b64(ssh_digest_alg_name(dgst_alg), 1244 dgst_raw, dgst_raw_len); 1245 break; 1246 case SSH_FP_BUBBLEBABBLE: 1247 retval = fingerprint_bubblebabble(dgst_raw, dgst_raw_len); 1248 break; 1249 case SSH_FP_RANDOMART: 1250 retval = fingerprint_randomart(ssh_digest_alg_name(dgst_alg), 1251 dgst_raw, dgst_raw_len, k); 1252 break; 1253 default: 1254 freezero(dgst_raw, dgst_raw_len); 1255 return NULL; 1256 } 1257 freezero(dgst_raw, dgst_raw_len); 1258 return retval; 1259 } 1260 1261 static int 1262 peek_type_nid(const char *s, size_t l, int *nid) 1263 { 1264 const struct keytype *kt; 1265 1266 for (kt = keytypes; kt->type != -1; kt++) { 1267 if (kt->name == NULL || strlen(kt->name) != l) 1268 continue; 1269 if (memcmp(s, kt->name, l) == 0) { 1270 *nid = -1; 1271 if (key_type_is_ecdsa_variant(kt->type)) 1272 *nid = kt->nid; 1273 return kt->type; 1274 } 1275 } 1276 return KEY_UNSPEC; 1277 } 1278 1279 1280 /* XXX this can now be made const char * */ 1281 int 1282 sshkey_read(struct sshkey *ret, char **cpp) 1283 { 1284 struct sshkey *k; 1285 char *cp, *blobcopy; 1286 size_t space; 1287 int r, type, curve_nid = -1; 1288 struct sshbuf *blob; 1289 1290 if (ret == NULL) 1291 return SSH_ERR_INVALID_ARGUMENT; 1292 1293 switch (ret->type) { 1294 case KEY_UNSPEC: 1295 case KEY_RSA: 1296 case KEY_DSA: 1297 case KEY_ECDSA: 1298 case KEY_ECDSA_SK: 1299 case KEY_ED25519: 1300 case KEY_ED25519_SK: 1301 case KEY_DSA_CERT: 1302 case KEY_ECDSA_CERT: 1303 case KEY_ECDSA_SK_CERT: 1304 case KEY_RSA_CERT: 1305 case KEY_ED25519_CERT: 1306 case KEY_ED25519_SK_CERT: 1307 #ifdef WITH_XMSS 1308 case KEY_XMSS: 1309 case KEY_XMSS_CERT: 1310 #endif /* WITH_XMSS */ 1311 break; /* ok */ 1312 default: 1313 return SSH_ERR_INVALID_ARGUMENT; 1314 } 1315 1316 /* Decode type */ 1317 cp = *cpp; 1318 space = strcspn(cp, " \t"); 1319 if (space == strlen(cp)) 1320 return SSH_ERR_INVALID_FORMAT; 1321 if ((type = peek_type_nid(cp, space, &curve_nid)) == KEY_UNSPEC) 1322 return SSH_ERR_INVALID_FORMAT; 1323 1324 /* skip whitespace */ 1325 for (cp += space; *cp == ' ' || *cp == '\t'; cp++) 1326 ; 1327 if (*cp == '\0') 1328 return SSH_ERR_INVALID_FORMAT; 1329 if (ret->type != KEY_UNSPEC && ret->type != type) 1330 return SSH_ERR_KEY_TYPE_MISMATCH; 1331 if ((blob = sshbuf_new()) == NULL) 1332 return SSH_ERR_ALLOC_FAIL; 1333 1334 /* find end of keyblob and decode */ 1335 space = strcspn(cp, " \t"); 1336 if ((blobcopy = strndup(cp, space)) == NULL) { 1337 sshbuf_free(blob); 1338 return SSH_ERR_ALLOC_FAIL; 1339 } 1340 if ((r = sshbuf_b64tod(blob, blobcopy)) != 0) { 1341 free(blobcopy); 1342 sshbuf_free(blob); 1343 return r; 1344 } 1345 free(blobcopy); 1346 if ((r = sshkey_fromb(blob, &k)) != 0) { 1347 sshbuf_free(blob); 1348 return r; 1349 } 1350 sshbuf_free(blob); 1351 1352 /* skip whitespace and leave cp at start of comment */ 1353 for (cp += space; *cp == ' ' || *cp == '\t'; cp++) 1354 ; 1355 1356 /* ensure type of blob matches type at start of line */ 1357 if (k->type != type) { 1358 sshkey_free(k); 1359 return SSH_ERR_KEY_TYPE_MISMATCH; 1360 } 1361 if (key_type_is_ecdsa_variant(type) && curve_nid != k->ecdsa_nid) { 1362 sshkey_free(k); 1363 return SSH_ERR_EC_CURVE_MISMATCH; 1364 } 1365 1366 /* Fill in ret from parsed key */ 1367 ret->type = type; 1368 if (sshkey_is_cert(ret)) { 1369 if (!sshkey_is_cert(k)) { 1370 sshkey_free(k); 1371 return SSH_ERR_EXPECTED_CERT; 1372 } 1373 if (ret->cert != NULL) 1374 cert_free(ret->cert); 1375 ret->cert = k->cert; 1376 k->cert = NULL; 1377 } 1378 switch (sshkey_type_plain(ret->type)) { 1379 #ifdef WITH_OPENSSL 1380 case KEY_RSA: 1381 RSA_free(ret->rsa); 1382 ret->rsa = k->rsa; 1383 k->rsa = NULL; 1384 #ifdef DEBUG_PK 1385 RSA_print_fp(stderr, ret->rsa, 8); 1386 #endif 1387 break; 1388 case KEY_DSA: 1389 DSA_free(ret->dsa); 1390 ret->dsa = k->dsa; 1391 k->dsa = NULL; 1392 #ifdef DEBUG_PK 1393 DSA_print_fp(stderr, ret->dsa, 8); 1394 #endif 1395 break; 1396 case KEY_ECDSA: 1397 EC_KEY_free(ret->ecdsa); 1398 ret->ecdsa = k->ecdsa; 1399 ret->ecdsa_nid = k->ecdsa_nid; 1400 k->ecdsa = NULL; 1401 k->ecdsa_nid = -1; 1402 #ifdef DEBUG_PK 1403 sshkey_dump_ec_key(ret->ecdsa); 1404 #endif 1405 break; 1406 case KEY_ECDSA_SK: 1407 EC_KEY_free(ret->ecdsa); 1408 ret->ecdsa = k->ecdsa; 1409 ret->ecdsa_nid = k->ecdsa_nid; 1410 ret->sk_application = k->sk_application; 1411 k->ecdsa = NULL; 1412 k->ecdsa_nid = -1; 1413 k->sk_application = NULL; 1414 #ifdef DEBUG_PK 1415 sshkey_dump_ec_key(ret->ecdsa); 1416 fprintf(stderr, "App: %s\n", ret->sk_application); 1417 #endif 1418 break; 1419 #endif /* WITH_OPENSSL */ 1420 case KEY_ED25519: 1421 freezero(ret->ed25519_pk, ED25519_PK_SZ); 1422 ret->ed25519_pk = k->ed25519_pk; 1423 k->ed25519_pk = NULL; 1424 #ifdef DEBUG_PK 1425 /* XXX */ 1426 #endif 1427 break; 1428 case KEY_ED25519_SK: 1429 freezero(ret->ed25519_pk, ED25519_PK_SZ); 1430 ret->ed25519_pk = k->ed25519_pk; 1431 ret->sk_application = k->sk_application; 1432 k->ed25519_pk = NULL; 1433 k->sk_application = NULL; 1434 break; 1435 #ifdef WITH_XMSS 1436 case KEY_XMSS: 1437 free(ret->xmss_pk); 1438 ret->xmss_pk = k->xmss_pk; 1439 k->xmss_pk = NULL; 1440 free(ret->xmss_state); 1441 ret->xmss_state = k->xmss_state; 1442 k->xmss_state = NULL; 1443 free(ret->xmss_name); 1444 ret->xmss_name = k->xmss_name; 1445 k->xmss_name = NULL; 1446 free(ret->xmss_filename); 1447 ret->xmss_filename = k->xmss_filename; 1448 k->xmss_filename = NULL; 1449 #ifdef DEBUG_PK 1450 /* XXX */ 1451 #endif 1452 break; 1453 #endif /* WITH_XMSS */ 1454 default: 1455 sshkey_free(k); 1456 return SSH_ERR_INTERNAL_ERROR; 1457 } 1458 sshkey_free(k); 1459 1460 /* success */ 1461 *cpp = cp; 1462 return 0; 1463 } 1464 1465 int 1466 sshkey_to_base64(const struct sshkey *key, char **b64p) 1467 { 1468 int r = SSH_ERR_INTERNAL_ERROR; 1469 struct sshbuf *b = NULL; 1470 char *uu = NULL; 1471 1472 if (b64p != NULL) 1473 *b64p = NULL; 1474 if ((b = sshbuf_new()) == NULL) 1475 return SSH_ERR_ALLOC_FAIL; 1476 if ((r = sshkey_putb(key, b)) != 0) 1477 goto out; 1478 if ((uu = sshbuf_dtob64_string(b, 0)) == NULL) { 1479 r = SSH_ERR_ALLOC_FAIL; 1480 goto out; 1481 } 1482 /* Success */ 1483 if (b64p != NULL) { 1484 *b64p = uu; 1485 uu = NULL; 1486 } 1487 r = 0; 1488 out: 1489 sshbuf_free(b); 1490 free(uu); 1491 return r; 1492 } 1493 1494 int 1495 sshkey_format_text(const struct sshkey *key, struct sshbuf *b) 1496 { 1497 int r = SSH_ERR_INTERNAL_ERROR; 1498 char *uu = NULL; 1499 1500 if ((r = sshkey_to_base64(key, &uu)) != 0) 1501 goto out; 1502 if ((r = sshbuf_putf(b, "%s %s", 1503 sshkey_ssh_name(key), uu)) != 0) 1504 goto out; 1505 r = 0; 1506 out: 1507 free(uu); 1508 return r; 1509 } 1510 1511 int 1512 sshkey_write(const struct sshkey *key, FILE *f) 1513 { 1514 struct sshbuf *b = NULL; 1515 int r = SSH_ERR_INTERNAL_ERROR; 1516 1517 if ((b = sshbuf_new()) == NULL) 1518 return SSH_ERR_ALLOC_FAIL; 1519 if ((r = sshkey_format_text(key, b)) != 0) 1520 goto out; 1521 if (fwrite(sshbuf_ptr(b), sshbuf_len(b), 1, f) != 1) { 1522 if (feof(f)) 1523 errno = EPIPE; 1524 r = SSH_ERR_SYSTEM_ERROR; 1525 goto out; 1526 } 1527 /* Success */ 1528 r = 0; 1529 out: 1530 sshbuf_free(b); 1531 return r; 1532 } 1533 1534 const char * 1535 sshkey_cert_type(const struct sshkey *k) 1536 { 1537 switch (k->cert->type) { 1538 case SSH2_CERT_TYPE_USER: 1539 return "user"; 1540 case SSH2_CERT_TYPE_HOST: 1541 return "host"; 1542 default: 1543 return "unknown"; 1544 } 1545 } 1546 1547 #ifdef WITH_OPENSSL 1548 static int 1549 rsa_generate_private_key(u_int bits, RSA **rsap) 1550 { 1551 RSA *private = NULL; 1552 BIGNUM *f4 = NULL; 1553 int ret = SSH_ERR_INTERNAL_ERROR; 1554 1555 if (rsap == NULL) 1556 return SSH_ERR_INVALID_ARGUMENT; 1557 if (bits < SSH_RSA_MINIMUM_MODULUS_SIZE || 1558 bits > SSHBUF_MAX_BIGNUM * 8) 1559 return SSH_ERR_KEY_LENGTH; 1560 *rsap = NULL; 1561 if ((private = RSA_new()) == NULL || (f4 = BN_new()) == NULL) { 1562 ret = SSH_ERR_ALLOC_FAIL; 1563 goto out; 1564 } 1565 if (!BN_set_word(f4, RSA_F4) || 1566 !RSA_generate_key_ex(private, bits, f4, NULL)) { 1567 ret = SSH_ERR_LIBCRYPTO_ERROR; 1568 goto out; 1569 } 1570 *rsap = private; 1571 private = NULL; 1572 ret = 0; 1573 out: 1574 RSA_free(private); 1575 BN_free(f4); 1576 return ret; 1577 } 1578 1579 static int 1580 dsa_generate_private_key(u_int bits, DSA **dsap) 1581 { 1582 DSA *private; 1583 int ret = SSH_ERR_INTERNAL_ERROR; 1584 1585 if (dsap == NULL) 1586 return SSH_ERR_INVALID_ARGUMENT; 1587 if (bits != 1024) 1588 return SSH_ERR_KEY_LENGTH; 1589 if ((private = DSA_new()) == NULL) { 1590 ret = SSH_ERR_ALLOC_FAIL; 1591 goto out; 1592 } 1593 *dsap = NULL; 1594 if (!DSA_generate_parameters_ex(private, bits, NULL, 0, NULL, 1595 NULL, NULL) || !DSA_generate_key(private)) { 1596 ret = SSH_ERR_LIBCRYPTO_ERROR; 1597 goto out; 1598 } 1599 *dsap = private; 1600 private = NULL; 1601 ret = 0; 1602 out: 1603 DSA_free(private); 1604 return ret; 1605 } 1606 1607 int 1608 sshkey_ecdsa_key_to_nid(EC_KEY *k) 1609 { 1610 EC_GROUP *eg; 1611 int nids[] = { 1612 NID_X9_62_prime256v1, 1613 NID_secp384r1, 1614 NID_secp521r1, 1615 -1 1616 }; 1617 int nid; 1618 u_int i; 1619 const EC_GROUP *g = EC_KEY_get0_group(k); 1620 1621 /* 1622 * The group may be stored in a ASN.1 encoded private key in one of two 1623 * ways: as a "named group", which is reconstituted by ASN.1 object ID 1624 * or explicit group parameters encoded into the key blob. Only the 1625 * "named group" case sets the group NID for us, but we can figure 1626 * it out for the other case by comparing against all the groups that 1627 * are supported. 1628 */ 1629 if ((nid = EC_GROUP_get_curve_name(g)) > 0) 1630 return nid; 1631 for (i = 0; nids[i] != -1; i++) { 1632 if ((eg = EC_GROUP_new_by_curve_name(nids[i])) == NULL) 1633 return -1; 1634 if (EC_GROUP_cmp(g, eg, NULL) == 0) 1635 break; 1636 EC_GROUP_free(eg); 1637 } 1638 if (nids[i] != -1) { 1639 /* Use the group with the NID attached */ 1640 EC_GROUP_set_asn1_flag(eg, OPENSSL_EC_NAMED_CURVE); 1641 if (EC_KEY_set_group(k, eg) != 1) { 1642 EC_GROUP_free(eg); 1643 return -1; 1644 } 1645 } 1646 return nids[i]; 1647 } 1648 1649 static int 1650 ecdsa_generate_private_key(u_int bits, int *nid, EC_KEY **ecdsap) 1651 { 1652 EC_KEY *private; 1653 int ret = SSH_ERR_INTERNAL_ERROR; 1654 1655 if (nid == NULL || ecdsap == NULL) 1656 return SSH_ERR_INVALID_ARGUMENT; 1657 if ((*nid = sshkey_ecdsa_bits_to_nid(bits)) == -1) 1658 return SSH_ERR_KEY_LENGTH; 1659 *ecdsap = NULL; 1660 if ((private = EC_KEY_new_by_curve_name(*nid)) == NULL) { 1661 ret = SSH_ERR_ALLOC_FAIL; 1662 goto out; 1663 } 1664 if (EC_KEY_generate_key(private) != 1) { 1665 ret = SSH_ERR_LIBCRYPTO_ERROR; 1666 goto out; 1667 } 1668 EC_KEY_set_asn1_flag(private, OPENSSL_EC_NAMED_CURVE); 1669 *ecdsap = private; 1670 private = NULL; 1671 ret = 0; 1672 out: 1673 EC_KEY_free(private); 1674 return ret; 1675 } 1676 #endif /* WITH_OPENSSL */ 1677 1678 int 1679 sshkey_generate(int type, u_int bits, struct sshkey **keyp) 1680 { 1681 struct sshkey *k; 1682 int ret = SSH_ERR_INTERNAL_ERROR; 1683 1684 if (keyp == NULL) 1685 return SSH_ERR_INVALID_ARGUMENT; 1686 *keyp = NULL; 1687 if ((k = sshkey_new(KEY_UNSPEC)) == NULL) 1688 return SSH_ERR_ALLOC_FAIL; 1689 switch (type) { 1690 case KEY_ED25519: 1691 if ((k->ed25519_pk = malloc(ED25519_PK_SZ)) == NULL || 1692 (k->ed25519_sk = malloc(ED25519_SK_SZ)) == NULL) { 1693 ret = SSH_ERR_ALLOC_FAIL; 1694 break; 1695 } 1696 crypto_sign_ed25519_keypair(k->ed25519_pk, k->ed25519_sk); 1697 ret = 0; 1698 break; 1699 #ifdef WITH_XMSS 1700 case KEY_XMSS: 1701 ret = sshkey_xmss_generate_private_key(k, bits); 1702 break; 1703 #endif /* WITH_XMSS */ 1704 #ifdef WITH_OPENSSL 1705 case KEY_DSA: 1706 ret = dsa_generate_private_key(bits, &k->dsa); 1707 break; 1708 case KEY_ECDSA: 1709 ret = ecdsa_generate_private_key(bits, &k->ecdsa_nid, 1710 &k->ecdsa); 1711 break; 1712 case KEY_RSA: 1713 ret = rsa_generate_private_key(bits, &k->rsa); 1714 break; 1715 #endif /* WITH_OPENSSL */ 1716 default: 1717 ret = SSH_ERR_INVALID_ARGUMENT; 1718 } 1719 if (ret == 0) { 1720 k->type = type; 1721 *keyp = k; 1722 } else 1723 sshkey_free(k); 1724 return ret; 1725 } 1726 1727 int 1728 sshkey_cert_copy(const struct sshkey *from_key, struct sshkey *to_key) 1729 { 1730 u_int i; 1731 const struct sshkey_cert *from; 1732 struct sshkey_cert *to; 1733 int r = SSH_ERR_INTERNAL_ERROR; 1734 1735 if (to_key == NULL || (from = from_key->cert) == NULL) 1736 return SSH_ERR_INVALID_ARGUMENT; 1737 1738 if ((to = cert_new()) == NULL) 1739 return SSH_ERR_ALLOC_FAIL; 1740 1741 if ((r = sshbuf_putb(to->certblob, from->certblob)) != 0 || 1742 (r = sshbuf_putb(to->critical, from->critical)) != 0 || 1743 (r = sshbuf_putb(to->extensions, from->extensions)) != 0) 1744 goto out; 1745 1746 to->serial = from->serial; 1747 to->type = from->type; 1748 if (from->key_id == NULL) 1749 to->key_id = NULL; 1750 else if ((to->key_id = strdup(from->key_id)) == NULL) { 1751 r = SSH_ERR_ALLOC_FAIL; 1752 goto out; 1753 } 1754 to->valid_after = from->valid_after; 1755 to->valid_before = from->valid_before; 1756 if (from->signature_key == NULL) 1757 to->signature_key = NULL; 1758 else if ((r = sshkey_from_private(from->signature_key, 1759 &to->signature_key)) != 0) 1760 goto out; 1761 if (from->signature_type != NULL && 1762 (to->signature_type = strdup(from->signature_type)) == NULL) { 1763 r = SSH_ERR_ALLOC_FAIL; 1764 goto out; 1765 } 1766 if (from->nprincipals > SSHKEY_CERT_MAX_PRINCIPALS) { 1767 r = SSH_ERR_INVALID_ARGUMENT; 1768 goto out; 1769 } 1770 if (from->nprincipals > 0) { 1771 if ((to->principals = calloc(from->nprincipals, 1772 sizeof(*to->principals))) == NULL) { 1773 r = SSH_ERR_ALLOC_FAIL; 1774 goto out; 1775 } 1776 for (i = 0; i < from->nprincipals; i++) { 1777 to->principals[i] = strdup(from->principals[i]); 1778 if (to->principals[i] == NULL) { 1779 to->nprincipals = i; 1780 r = SSH_ERR_ALLOC_FAIL; 1781 goto out; 1782 } 1783 } 1784 } 1785 to->nprincipals = from->nprincipals; 1786 1787 /* success */ 1788 cert_free(to_key->cert); 1789 to_key->cert = to; 1790 to = NULL; 1791 r = 0; 1792 out: 1793 cert_free(to); 1794 return r; 1795 } 1796 1797 int 1798 sshkey_from_private(const struct sshkey *k, struct sshkey **pkp) 1799 { 1800 struct sshkey *n = NULL; 1801 int r = SSH_ERR_INTERNAL_ERROR; 1802 #ifdef WITH_OPENSSL 1803 const BIGNUM *rsa_n, *rsa_e; 1804 BIGNUM *rsa_n_dup = NULL, *rsa_e_dup = NULL; 1805 const BIGNUM *dsa_p, *dsa_q, *dsa_g, *dsa_pub_key; 1806 BIGNUM *dsa_p_dup = NULL, *dsa_q_dup = NULL, *dsa_g_dup = NULL; 1807 BIGNUM *dsa_pub_key_dup = NULL; 1808 #endif /* WITH_OPENSSL */ 1809 1810 *pkp = NULL; 1811 if ((n = sshkey_new(k->type)) == NULL) { 1812 r = SSH_ERR_ALLOC_FAIL; 1813 goto out; 1814 } 1815 switch (k->type) { 1816 #ifdef WITH_OPENSSL 1817 case KEY_DSA: 1818 case KEY_DSA_CERT: 1819 DSA_get0_pqg(k->dsa, &dsa_p, &dsa_q, &dsa_g); 1820 DSA_get0_key(k->dsa, &dsa_pub_key, NULL); 1821 if ((dsa_p_dup = BN_dup(dsa_p)) == NULL || 1822 (dsa_q_dup = BN_dup(dsa_q)) == NULL || 1823 (dsa_g_dup = BN_dup(dsa_g)) == NULL || 1824 (dsa_pub_key_dup = BN_dup(dsa_pub_key)) == NULL) { 1825 r = SSH_ERR_ALLOC_FAIL; 1826 goto out; 1827 } 1828 if (!DSA_set0_pqg(n->dsa, dsa_p_dup, dsa_q_dup, dsa_g_dup)) { 1829 r = SSH_ERR_LIBCRYPTO_ERROR; 1830 goto out; 1831 } 1832 dsa_p_dup = dsa_q_dup = dsa_g_dup = NULL; /* transferred */ 1833 if (!DSA_set0_key(n->dsa, dsa_pub_key_dup, NULL)) { 1834 r = SSH_ERR_LIBCRYPTO_ERROR; 1835 goto out; 1836 } 1837 dsa_pub_key_dup = NULL; /* transferred */ 1838 1839 break; 1840 case KEY_ECDSA: 1841 case KEY_ECDSA_CERT: 1842 case KEY_ECDSA_SK: 1843 case KEY_ECDSA_SK_CERT: 1844 n->ecdsa_nid = k->ecdsa_nid; 1845 n->ecdsa = EC_KEY_new_by_curve_name(k->ecdsa_nid); 1846 if (n->ecdsa == NULL) { 1847 r = SSH_ERR_ALLOC_FAIL; 1848 goto out; 1849 } 1850 if (EC_KEY_set_public_key(n->ecdsa, 1851 EC_KEY_get0_public_key(k->ecdsa)) != 1) { 1852 r = SSH_ERR_LIBCRYPTO_ERROR; 1853 goto out; 1854 } 1855 if (k->type != KEY_ECDSA_SK && k->type != KEY_ECDSA_SK_CERT) 1856 break; 1857 /* Append security-key application string */ 1858 if ((n->sk_application = strdup(k->sk_application)) == NULL) 1859 goto out; 1860 break; 1861 case KEY_RSA: 1862 case KEY_RSA_CERT: 1863 RSA_get0_key(k->rsa, &rsa_n, &rsa_e, NULL); 1864 if ((rsa_n_dup = BN_dup(rsa_n)) == NULL || 1865 (rsa_e_dup = BN_dup(rsa_e)) == NULL) { 1866 r = SSH_ERR_ALLOC_FAIL; 1867 goto out; 1868 } 1869 if (!RSA_set0_key(n->rsa, rsa_n_dup, rsa_e_dup, NULL)) { 1870 r = SSH_ERR_LIBCRYPTO_ERROR; 1871 goto out; 1872 } 1873 rsa_n_dup = rsa_e_dup = NULL; /* transferred */ 1874 break; 1875 #endif /* WITH_OPENSSL */ 1876 case KEY_ED25519: 1877 case KEY_ED25519_CERT: 1878 case KEY_ED25519_SK: 1879 case KEY_ED25519_SK_CERT: 1880 if (k->ed25519_pk != NULL) { 1881 if ((n->ed25519_pk = malloc(ED25519_PK_SZ)) == NULL) { 1882 r = SSH_ERR_ALLOC_FAIL; 1883 goto out; 1884 } 1885 memcpy(n->ed25519_pk, k->ed25519_pk, ED25519_PK_SZ); 1886 } 1887 if (k->type != KEY_ED25519_SK && 1888 k->type != KEY_ED25519_SK_CERT) 1889 break; 1890 /* Append security-key application string */ 1891 if ((n->sk_application = strdup(k->sk_application)) == NULL) 1892 goto out; 1893 break; 1894 #ifdef WITH_XMSS 1895 case KEY_XMSS: 1896 case KEY_XMSS_CERT: 1897 if ((r = sshkey_xmss_init(n, k->xmss_name)) != 0) 1898 goto out; 1899 if (k->xmss_pk != NULL) { 1900 u_int32_t left; 1901 size_t pklen = sshkey_xmss_pklen(k); 1902 if (pklen == 0 || sshkey_xmss_pklen(n) != pklen) { 1903 r = SSH_ERR_INTERNAL_ERROR; 1904 goto out; 1905 } 1906 if ((n->xmss_pk = malloc(pklen)) == NULL) { 1907 r = SSH_ERR_ALLOC_FAIL; 1908 goto out; 1909 } 1910 memcpy(n->xmss_pk, k->xmss_pk, pklen); 1911 /* simulate number of signatures left on pubkey */ 1912 left = sshkey_xmss_signatures_left(k); 1913 if (left) 1914 sshkey_xmss_enable_maxsign(n, left); 1915 } 1916 break; 1917 #endif /* WITH_XMSS */ 1918 default: 1919 r = SSH_ERR_KEY_TYPE_UNKNOWN; 1920 goto out; 1921 } 1922 if (sshkey_is_cert(k) && (r = sshkey_cert_copy(k, n)) != 0) 1923 goto out; 1924 /* success */ 1925 *pkp = n; 1926 n = NULL; 1927 r = 0; 1928 out: 1929 sshkey_free(n); 1930 #ifdef WITH_OPENSSL 1931 BN_clear_free(rsa_n_dup); 1932 BN_clear_free(rsa_e_dup); 1933 BN_clear_free(dsa_p_dup); 1934 BN_clear_free(dsa_q_dup); 1935 BN_clear_free(dsa_g_dup); 1936 BN_clear_free(dsa_pub_key_dup); 1937 #endif /* WITH_OPENSSL */ 1938 1939 return r; 1940 } 1941 1942 int 1943 sshkey_is_shielded(struct sshkey *k) 1944 { 1945 return k != NULL && k->shielded_private != NULL; 1946 } 1947 1948 int 1949 sshkey_shield_private(struct sshkey *k) 1950 { 1951 struct sshbuf *prvbuf = NULL; 1952 u_char *prekey = NULL, *enc = NULL, keyiv[SSH_DIGEST_MAX_LENGTH]; 1953 struct sshcipher_ctx *cctx = NULL; 1954 const struct sshcipher *cipher; 1955 size_t i, enclen = 0; 1956 struct sshkey *kswap = NULL, tmp; 1957 int r = SSH_ERR_INTERNAL_ERROR; 1958 1959 #ifdef DEBUG_PK 1960 fprintf(stderr, "%s: entering for %s\n", __func__, sshkey_ssh_name(k)); 1961 #endif 1962 if ((cipher = cipher_by_name(SSHKEY_SHIELD_CIPHER)) == NULL) { 1963 r = SSH_ERR_INVALID_ARGUMENT; 1964 goto out; 1965 } 1966 if (cipher_keylen(cipher) + cipher_ivlen(cipher) > 1967 ssh_digest_bytes(SSHKEY_SHIELD_PREKEY_HASH)) { 1968 r = SSH_ERR_INTERNAL_ERROR; 1969 goto out; 1970 } 1971 1972 /* Prepare a random pre-key, and from it an ephemeral key */ 1973 if ((prekey = malloc(SSHKEY_SHIELD_PREKEY_LEN)) == NULL) { 1974 r = SSH_ERR_ALLOC_FAIL; 1975 goto out; 1976 } 1977 arc4random_buf(prekey, SSHKEY_SHIELD_PREKEY_LEN); 1978 if ((r = ssh_digest_memory(SSHKEY_SHIELD_PREKEY_HASH, 1979 prekey, SSHKEY_SHIELD_PREKEY_LEN, 1980 keyiv, SSH_DIGEST_MAX_LENGTH)) != 0) 1981 goto out; 1982 #ifdef DEBUG_PK 1983 fprintf(stderr, "%s: key+iv\n", __func__); 1984 sshbuf_dump_data(keyiv, ssh_digest_bytes(SSHKEY_SHIELD_PREKEY_HASH), 1985 stderr); 1986 #endif 1987 if ((r = cipher_init(&cctx, cipher, keyiv, cipher_keylen(cipher), 1988 keyiv + cipher_keylen(cipher), cipher_ivlen(cipher), 1)) != 0) 1989 goto out; 1990 1991 /* Serialise and encrypt the private key using the ephemeral key */ 1992 if ((prvbuf = sshbuf_new()) == NULL) { 1993 r = SSH_ERR_ALLOC_FAIL; 1994 goto out; 1995 } 1996 if (sshkey_is_shielded(k) && (r = sshkey_unshield_private(k)) != 0) 1997 goto out; 1998 if ((r = sshkey_private_serialize_opt(k, prvbuf, 1999 SSHKEY_SERIALIZE_SHIELD)) != 0) 2000 goto out; 2001 /* pad to cipher blocksize */ 2002 i = 0; 2003 while (sshbuf_len(prvbuf) % cipher_blocksize(cipher)) { 2004 if ((r = sshbuf_put_u8(prvbuf, ++i & 0xff)) != 0) 2005 goto out; 2006 } 2007 #ifdef DEBUG_PK 2008 fprintf(stderr, "%s: serialised\n", __func__); 2009 sshbuf_dump(prvbuf, stderr); 2010 #endif 2011 /* encrypt */ 2012 enclen = sshbuf_len(prvbuf); 2013 if ((enc = malloc(enclen)) == NULL) { 2014 r = SSH_ERR_ALLOC_FAIL; 2015 goto out; 2016 } 2017 if ((r = cipher_crypt(cctx, 0, enc, 2018 sshbuf_ptr(prvbuf), sshbuf_len(prvbuf), 0, 0)) != 0) 2019 goto out; 2020 #ifdef DEBUG_PK 2021 fprintf(stderr, "%s: encrypted\n", __func__); 2022 sshbuf_dump_data(enc, enclen, stderr); 2023 #endif 2024 2025 /* Make a scrubbed, public-only copy of our private key argument */ 2026 if ((r = sshkey_from_private(k, &kswap)) != 0) 2027 goto out; 2028 2029 /* Swap the private key out (it will be destroyed below) */ 2030 tmp = *kswap; 2031 *kswap = *k; 2032 *k = tmp; 2033 2034 /* Insert the shielded key into our argument */ 2035 k->shielded_private = enc; 2036 k->shielded_len = enclen; 2037 k->shield_prekey = prekey; 2038 k->shield_prekey_len = SSHKEY_SHIELD_PREKEY_LEN; 2039 enc = prekey = NULL; /* transferred */ 2040 enclen = 0; 2041 2042 /* preserve key fields that are required for correct operation */ 2043 k->sk_flags = kswap->sk_flags; 2044 2045 /* success */ 2046 r = 0; 2047 2048 out: 2049 /* XXX behaviour on error - invalidate original private key? */ 2050 cipher_free(cctx); 2051 explicit_bzero(keyiv, sizeof(keyiv)); 2052 explicit_bzero(&tmp, sizeof(tmp)); 2053 freezero(enc, enclen); 2054 freezero(prekey, SSHKEY_SHIELD_PREKEY_LEN); 2055 sshkey_free(kswap); 2056 sshbuf_free(prvbuf); 2057 return r; 2058 } 2059 2060 int 2061 sshkey_unshield_private(struct sshkey *k) 2062 { 2063 struct sshbuf *prvbuf = NULL; 2064 u_char pad, *cp, keyiv[SSH_DIGEST_MAX_LENGTH]; 2065 struct sshcipher_ctx *cctx = NULL; 2066 const struct sshcipher *cipher; 2067 size_t i; 2068 struct sshkey *kswap = NULL, tmp; 2069 int r = SSH_ERR_INTERNAL_ERROR; 2070 2071 #ifdef DEBUG_PK 2072 fprintf(stderr, "%s: entering for %s\n", __func__, sshkey_ssh_name(k)); 2073 #endif 2074 if (!sshkey_is_shielded(k)) 2075 return 0; /* nothing to do */ 2076 2077 if ((cipher = cipher_by_name(SSHKEY_SHIELD_CIPHER)) == NULL) { 2078 r = SSH_ERR_INVALID_ARGUMENT; 2079 goto out; 2080 } 2081 if (cipher_keylen(cipher) + cipher_ivlen(cipher) > 2082 ssh_digest_bytes(SSHKEY_SHIELD_PREKEY_HASH)) { 2083 r = SSH_ERR_INTERNAL_ERROR; 2084 goto out; 2085 } 2086 /* check size of shielded key blob */ 2087 if (k->shielded_len < cipher_blocksize(cipher) || 2088 (k->shielded_len % cipher_blocksize(cipher)) != 0) { 2089 r = SSH_ERR_INVALID_FORMAT; 2090 goto out; 2091 } 2092 2093 /* Calculate the ephemeral key from the prekey */ 2094 if ((r = ssh_digest_memory(SSHKEY_SHIELD_PREKEY_HASH, 2095 k->shield_prekey, k->shield_prekey_len, 2096 keyiv, SSH_DIGEST_MAX_LENGTH)) != 0) 2097 goto out; 2098 if ((r = cipher_init(&cctx, cipher, keyiv, cipher_keylen(cipher), 2099 keyiv + cipher_keylen(cipher), cipher_ivlen(cipher), 0)) != 0) 2100 goto out; 2101 #ifdef DEBUG_PK 2102 fprintf(stderr, "%s: key+iv\n", __func__); 2103 sshbuf_dump_data(keyiv, ssh_digest_bytes(SSHKEY_SHIELD_PREKEY_HASH), 2104 stderr); 2105 #endif 2106 2107 /* Decrypt and parse the shielded private key using the ephemeral key */ 2108 if ((prvbuf = sshbuf_new()) == NULL) { 2109 r = SSH_ERR_ALLOC_FAIL; 2110 goto out; 2111 } 2112 if ((r = sshbuf_reserve(prvbuf, k->shielded_len, &cp)) != 0) 2113 goto out; 2114 /* decrypt */ 2115 #ifdef DEBUG_PK 2116 fprintf(stderr, "%s: encrypted\n", __func__); 2117 sshbuf_dump_data(k->shielded_private, k->shielded_len, stderr); 2118 #endif 2119 if ((r = cipher_crypt(cctx, 0, cp, 2120 k->shielded_private, k->shielded_len, 0, 0)) != 0) 2121 goto out; 2122 #ifdef DEBUG_PK 2123 fprintf(stderr, "%s: serialised\n", __func__); 2124 sshbuf_dump(prvbuf, stderr); 2125 #endif 2126 /* Parse private key */ 2127 if ((r = sshkey_private_deserialize(prvbuf, &kswap)) != 0) 2128 goto out; 2129 /* Check deterministic padding */ 2130 i = 0; 2131 while (sshbuf_len(prvbuf)) { 2132 if ((r = sshbuf_get_u8(prvbuf, &pad)) != 0) 2133 goto out; 2134 if (pad != (++i & 0xff)) { 2135 r = SSH_ERR_INVALID_FORMAT; 2136 goto out; 2137 } 2138 } 2139 2140 /* Swap the parsed key back into place */ 2141 tmp = *kswap; 2142 *kswap = *k; 2143 *k = tmp; 2144 2145 /* success */ 2146 r = 0; 2147 2148 out: 2149 cipher_free(cctx); 2150 explicit_bzero(keyiv, sizeof(keyiv)); 2151 explicit_bzero(&tmp, sizeof(tmp)); 2152 sshkey_free(kswap); 2153 sshbuf_free(prvbuf); 2154 return r; 2155 } 2156 2157 static int 2158 cert_parse(struct sshbuf *b, struct sshkey *key, struct sshbuf *certbuf) 2159 { 2160 struct sshbuf *principals = NULL, *crit = NULL; 2161 struct sshbuf *exts = NULL, *ca = NULL; 2162 u_char *sig = NULL; 2163 size_t signed_len = 0, slen = 0, kidlen = 0; 2164 int ret = SSH_ERR_INTERNAL_ERROR; 2165 2166 /* Copy the entire key blob for verification and later serialisation */ 2167 if ((ret = sshbuf_putb(key->cert->certblob, certbuf)) != 0) 2168 return ret; 2169 2170 /* Parse body of certificate up to signature */ 2171 if ((ret = sshbuf_get_u64(b, &key->cert->serial)) != 0 || 2172 (ret = sshbuf_get_u32(b, &key->cert->type)) != 0 || 2173 (ret = sshbuf_get_cstring(b, &key->cert->key_id, &kidlen)) != 0 || 2174 (ret = sshbuf_froms(b, &principals)) != 0 || 2175 (ret = sshbuf_get_u64(b, &key->cert->valid_after)) != 0 || 2176 (ret = sshbuf_get_u64(b, &key->cert->valid_before)) != 0 || 2177 (ret = sshbuf_froms(b, &crit)) != 0 || 2178 (ret = sshbuf_froms(b, &exts)) != 0 || 2179 (ret = sshbuf_get_string_direct(b, NULL, NULL)) != 0 || 2180 (ret = sshbuf_froms(b, &ca)) != 0) { 2181 /* XXX debug print error for ret */ 2182 ret = SSH_ERR_INVALID_FORMAT; 2183 goto out; 2184 } 2185 2186 /* Signature is left in the buffer so we can calculate this length */ 2187 signed_len = sshbuf_len(key->cert->certblob) - sshbuf_len(b); 2188 2189 if ((ret = sshbuf_get_string(b, &sig, &slen)) != 0) { 2190 ret = SSH_ERR_INVALID_FORMAT; 2191 goto out; 2192 } 2193 2194 if (key->cert->type != SSH2_CERT_TYPE_USER && 2195 key->cert->type != SSH2_CERT_TYPE_HOST) { 2196 ret = SSH_ERR_KEY_CERT_UNKNOWN_TYPE; 2197 goto out; 2198 } 2199 2200 /* Parse principals section */ 2201 while (sshbuf_len(principals) > 0) { 2202 char *principal = NULL; 2203 char **oprincipals = NULL; 2204 2205 if (key->cert->nprincipals >= SSHKEY_CERT_MAX_PRINCIPALS) { 2206 ret = SSH_ERR_INVALID_FORMAT; 2207 goto out; 2208 } 2209 if ((ret = sshbuf_get_cstring(principals, &principal, 2210 NULL)) != 0) { 2211 ret = SSH_ERR_INVALID_FORMAT; 2212 goto out; 2213 } 2214 oprincipals = key->cert->principals; 2215 key->cert->principals = recallocarray(key->cert->principals, 2216 key->cert->nprincipals, key->cert->nprincipals + 1, 2217 sizeof(*key->cert->principals)); 2218 if (key->cert->principals == NULL) { 2219 free(principal); 2220 key->cert->principals = oprincipals; 2221 ret = SSH_ERR_ALLOC_FAIL; 2222 goto out; 2223 } 2224 key->cert->principals[key->cert->nprincipals++] = principal; 2225 } 2226 2227 /* 2228 * Stash a copies of the critical options and extensions sections 2229 * for later use. 2230 */ 2231 if ((ret = sshbuf_putb(key->cert->critical, crit)) != 0 || 2232 (exts != NULL && 2233 (ret = sshbuf_putb(key->cert->extensions, exts)) != 0)) 2234 goto out; 2235 2236 /* 2237 * Validate critical options and extensions sections format. 2238 */ 2239 while (sshbuf_len(crit) != 0) { 2240 if ((ret = sshbuf_get_string_direct(crit, NULL, NULL)) != 0 || 2241 (ret = sshbuf_get_string_direct(crit, NULL, NULL)) != 0) { 2242 sshbuf_reset(key->cert->critical); 2243 ret = SSH_ERR_INVALID_FORMAT; 2244 goto out; 2245 } 2246 } 2247 while (exts != NULL && sshbuf_len(exts) != 0) { 2248 if ((ret = sshbuf_get_string_direct(exts, NULL, NULL)) != 0 || 2249 (ret = sshbuf_get_string_direct(exts, NULL, NULL)) != 0) { 2250 sshbuf_reset(key->cert->extensions); 2251 ret = SSH_ERR_INVALID_FORMAT; 2252 goto out; 2253 } 2254 } 2255 2256 /* Parse CA key and check signature */ 2257 if (sshkey_from_blob_internal(ca, &key->cert->signature_key, 0) != 0) { 2258 ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY; 2259 goto out; 2260 } 2261 if (!sshkey_type_is_valid_ca(key->cert->signature_key->type)) { 2262 ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY; 2263 goto out; 2264 } 2265 if ((ret = sshkey_verify(key->cert->signature_key, sig, slen, 2266 sshbuf_ptr(key->cert->certblob), signed_len, NULL, 0, NULL)) != 0) 2267 goto out; 2268 if ((ret = sshkey_get_sigtype(sig, slen, 2269 &key->cert->signature_type)) != 0) 2270 goto out; 2271 2272 /* Success */ 2273 ret = 0; 2274 out: 2275 sshbuf_free(ca); 2276 sshbuf_free(crit); 2277 sshbuf_free(exts); 2278 sshbuf_free(principals); 2279 free(sig); 2280 return ret; 2281 } 2282 2283 #ifdef WITH_OPENSSL 2284 static int 2285 check_rsa_length(const RSA *rsa) 2286 { 2287 const BIGNUM *rsa_n; 2288 2289 RSA_get0_key(rsa, &rsa_n, NULL, NULL); 2290 if (BN_num_bits(rsa_n) < SSH_RSA_MINIMUM_MODULUS_SIZE) 2291 return SSH_ERR_KEY_LENGTH; 2292 return 0; 2293 } 2294 #endif /* WITH_OPENSSL */ 2295 2296 static int 2297 sshkey_from_blob_internal(struct sshbuf *b, struct sshkey **keyp, 2298 int allow_cert) 2299 { 2300 int type, ret = SSH_ERR_INTERNAL_ERROR; 2301 char *ktype = NULL, *curve = NULL, *xmss_name = NULL; 2302 struct sshkey *key = NULL; 2303 size_t len; 2304 u_char *pk = NULL; 2305 struct sshbuf *copy; 2306 #ifdef WITH_OPENSSL 2307 EC_POINT *q = NULL; 2308 BIGNUM *rsa_n = NULL, *rsa_e = NULL; 2309 BIGNUM *dsa_p = NULL, *dsa_q = NULL, *dsa_g = NULL, *dsa_pub_key = NULL; 2310 #endif /* WITH_OPENSSL */ 2311 2312 #ifdef DEBUG_PK /* XXX */ 2313 sshbuf_dump(b, stderr); 2314 #endif 2315 if (keyp != NULL) 2316 *keyp = NULL; 2317 if ((copy = sshbuf_fromb(b)) == NULL) { 2318 ret = SSH_ERR_ALLOC_FAIL; 2319 goto out; 2320 } 2321 if (sshbuf_get_cstring(b, &ktype, NULL) != 0) { 2322 ret = SSH_ERR_INVALID_FORMAT; 2323 goto out; 2324 } 2325 2326 type = sshkey_type_from_name(ktype); 2327 if (!allow_cert && sshkey_type_is_cert(type)) { 2328 ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY; 2329 goto out; 2330 } 2331 switch (type) { 2332 #ifdef WITH_OPENSSL 2333 case KEY_RSA_CERT: 2334 /* Skip nonce */ 2335 if (sshbuf_get_string_direct(b, NULL, NULL) != 0) { 2336 ret = SSH_ERR_INVALID_FORMAT; 2337 goto out; 2338 } 2339 /* FALLTHROUGH */ 2340 case KEY_RSA: 2341 if ((key = sshkey_new(type)) == NULL) { 2342 ret = SSH_ERR_ALLOC_FAIL; 2343 goto out; 2344 } 2345 if (sshbuf_get_bignum2(b, &rsa_e) != 0 || 2346 sshbuf_get_bignum2(b, &rsa_n) != 0) { 2347 ret = SSH_ERR_INVALID_FORMAT; 2348 goto out; 2349 } 2350 if (!RSA_set0_key(key->rsa, rsa_n, rsa_e, NULL)) { 2351 ret = SSH_ERR_LIBCRYPTO_ERROR; 2352 goto out; 2353 } 2354 rsa_n = rsa_e = NULL; /* transferred */ 2355 if ((ret = check_rsa_length(key->rsa)) != 0) 2356 goto out; 2357 #ifdef DEBUG_PK 2358 RSA_print_fp(stderr, key->rsa, 8); 2359 #endif 2360 break; 2361 case KEY_DSA_CERT: 2362 /* Skip nonce */ 2363 if (sshbuf_get_string_direct(b, NULL, NULL) != 0) { 2364 ret = SSH_ERR_INVALID_FORMAT; 2365 goto out; 2366 } 2367 /* FALLTHROUGH */ 2368 case KEY_DSA: 2369 if ((key = sshkey_new(type)) == NULL) { 2370 ret = SSH_ERR_ALLOC_FAIL; 2371 goto out; 2372 } 2373 if (sshbuf_get_bignum2(b, &dsa_p) != 0 || 2374 sshbuf_get_bignum2(b, &dsa_q) != 0 || 2375 sshbuf_get_bignum2(b, &dsa_g) != 0 || 2376 sshbuf_get_bignum2(b, &dsa_pub_key) != 0) { 2377 ret = SSH_ERR_INVALID_FORMAT; 2378 goto out; 2379 } 2380 if (!DSA_set0_pqg(key->dsa, dsa_p, dsa_q, dsa_g)) { 2381 ret = SSH_ERR_LIBCRYPTO_ERROR; 2382 goto out; 2383 } 2384 dsa_p = dsa_q = dsa_g = NULL; /* transferred */ 2385 if (!DSA_set0_key(key->dsa, dsa_pub_key, NULL)) { 2386 ret = SSH_ERR_LIBCRYPTO_ERROR; 2387 goto out; 2388 } 2389 dsa_pub_key = NULL; /* transferred */ 2390 #ifdef DEBUG_PK 2391 DSA_print_fp(stderr, key->dsa, 8); 2392 #endif 2393 break; 2394 case KEY_ECDSA_CERT: 2395 case KEY_ECDSA_SK_CERT: 2396 /* Skip nonce */ 2397 if (sshbuf_get_string_direct(b, NULL, NULL) != 0) { 2398 ret = SSH_ERR_INVALID_FORMAT; 2399 goto out; 2400 } 2401 /* FALLTHROUGH */ 2402 case KEY_ECDSA: 2403 case KEY_ECDSA_SK: 2404 if ((key = sshkey_new(type)) == NULL) { 2405 ret = SSH_ERR_ALLOC_FAIL; 2406 goto out; 2407 } 2408 key->ecdsa_nid = sshkey_ecdsa_nid_from_name(ktype); 2409 if (sshbuf_get_cstring(b, &curve, NULL) != 0) { 2410 ret = SSH_ERR_INVALID_FORMAT; 2411 goto out; 2412 } 2413 if (key->ecdsa_nid != sshkey_curve_name_to_nid(curve)) { 2414 ret = SSH_ERR_EC_CURVE_MISMATCH; 2415 goto out; 2416 } 2417 EC_KEY_free(key->ecdsa); 2418 if ((key->ecdsa = EC_KEY_new_by_curve_name(key->ecdsa_nid)) 2419 == NULL) { 2420 ret = SSH_ERR_EC_CURVE_INVALID; 2421 goto out; 2422 } 2423 if ((q = EC_POINT_new(EC_KEY_get0_group(key->ecdsa))) == NULL) { 2424 ret = SSH_ERR_ALLOC_FAIL; 2425 goto out; 2426 } 2427 if (sshbuf_get_ec(b, q, EC_KEY_get0_group(key->ecdsa)) != 0) { 2428 ret = SSH_ERR_INVALID_FORMAT; 2429 goto out; 2430 } 2431 if (sshkey_ec_validate_public(EC_KEY_get0_group(key->ecdsa), 2432 q) != 0) { 2433 ret = SSH_ERR_KEY_INVALID_EC_VALUE; 2434 goto out; 2435 } 2436 if (EC_KEY_set_public_key(key->ecdsa, q) != 1) { 2437 /* XXX assume it is a allocation error */ 2438 ret = SSH_ERR_ALLOC_FAIL; 2439 goto out; 2440 } 2441 #ifdef DEBUG_PK 2442 sshkey_dump_ec_point(EC_KEY_get0_group(key->ecdsa), q); 2443 #endif 2444 if (type == KEY_ECDSA_SK || type == KEY_ECDSA_SK_CERT) { 2445 /* Parse additional security-key application string */ 2446 if (sshbuf_get_cstring(b, &key->sk_application, 2447 NULL) != 0) { 2448 ret = SSH_ERR_INVALID_FORMAT; 2449 goto out; 2450 } 2451 #ifdef DEBUG_PK 2452 fprintf(stderr, "App: %s\n", key->sk_application); 2453 #endif 2454 } 2455 break; 2456 #endif /* WITH_OPENSSL */ 2457 case KEY_ED25519_CERT: 2458 case KEY_ED25519_SK_CERT: 2459 /* Skip nonce */ 2460 if (sshbuf_get_string_direct(b, NULL, NULL) != 0) { 2461 ret = SSH_ERR_INVALID_FORMAT; 2462 goto out; 2463 } 2464 /* FALLTHROUGH */ 2465 case KEY_ED25519: 2466 case KEY_ED25519_SK: 2467 if ((ret = sshbuf_get_string(b, &pk, &len)) != 0) 2468 goto out; 2469 if (len != ED25519_PK_SZ) { 2470 ret = SSH_ERR_INVALID_FORMAT; 2471 goto out; 2472 } 2473 if ((key = sshkey_new(type)) == NULL) { 2474 ret = SSH_ERR_ALLOC_FAIL; 2475 goto out; 2476 } 2477 if (type == KEY_ED25519_SK || type == KEY_ED25519_SK_CERT) { 2478 /* Parse additional security-key application string */ 2479 if (sshbuf_get_cstring(b, &key->sk_application, 2480 NULL) != 0) { 2481 ret = SSH_ERR_INVALID_FORMAT; 2482 goto out; 2483 } 2484 #ifdef DEBUG_PK 2485 fprintf(stderr, "App: %s\n", key->sk_application); 2486 #endif 2487 } 2488 key->ed25519_pk = pk; 2489 pk = NULL; 2490 break; 2491 #ifdef WITH_XMSS 2492 case KEY_XMSS_CERT: 2493 /* Skip nonce */ 2494 if (sshbuf_get_string_direct(b, NULL, NULL) != 0) { 2495 ret = SSH_ERR_INVALID_FORMAT; 2496 goto out; 2497 } 2498 /* FALLTHROUGH */ 2499 case KEY_XMSS: 2500 if ((ret = sshbuf_get_cstring(b, &xmss_name, NULL)) != 0) 2501 goto out; 2502 if ((key = sshkey_new(type)) == NULL) { 2503 ret = SSH_ERR_ALLOC_FAIL; 2504 goto out; 2505 } 2506 if ((ret = sshkey_xmss_init(key, xmss_name)) != 0) 2507 goto out; 2508 if ((ret = sshbuf_get_string(b, &pk, &len)) != 0) 2509 goto out; 2510 if (len == 0 || len != sshkey_xmss_pklen(key)) { 2511 ret = SSH_ERR_INVALID_FORMAT; 2512 goto out; 2513 } 2514 key->xmss_pk = pk; 2515 pk = NULL; 2516 if (type != KEY_XMSS_CERT && 2517 (ret = sshkey_xmss_deserialize_pk_info(key, b)) != 0) 2518 goto out; 2519 break; 2520 #endif /* WITH_XMSS */ 2521 case KEY_UNSPEC: 2522 default: 2523 ret = SSH_ERR_KEY_TYPE_UNKNOWN; 2524 goto out; 2525 } 2526 2527 /* Parse certificate potion */ 2528 if (sshkey_is_cert(key) && (ret = cert_parse(b, key, copy)) != 0) 2529 goto out; 2530 2531 if (key != NULL && sshbuf_len(b) != 0) { 2532 ret = SSH_ERR_INVALID_FORMAT; 2533 goto out; 2534 } 2535 ret = 0; 2536 if (keyp != NULL) { 2537 *keyp = key; 2538 key = NULL; 2539 } 2540 out: 2541 sshbuf_free(copy); 2542 sshkey_free(key); 2543 free(xmss_name); 2544 free(ktype); 2545 free(curve); 2546 free(pk); 2547 #ifdef WITH_OPENSSL 2548 EC_POINT_free(q); 2549 BN_clear_free(rsa_n); 2550 BN_clear_free(rsa_e); 2551 BN_clear_free(dsa_p); 2552 BN_clear_free(dsa_q); 2553 BN_clear_free(dsa_g); 2554 BN_clear_free(dsa_pub_key); 2555 #endif /* WITH_OPENSSL */ 2556 return ret; 2557 } 2558 2559 int 2560 sshkey_from_blob(const u_char *blob, size_t blen, struct sshkey **keyp) 2561 { 2562 struct sshbuf *b; 2563 int r; 2564 2565 if ((b = sshbuf_from(blob, blen)) == NULL) 2566 return SSH_ERR_ALLOC_FAIL; 2567 r = sshkey_from_blob_internal(b, keyp, 1); 2568 sshbuf_free(b); 2569 return r; 2570 } 2571 2572 int 2573 sshkey_fromb(struct sshbuf *b, struct sshkey **keyp) 2574 { 2575 return sshkey_from_blob_internal(b, keyp, 1); 2576 } 2577 2578 int 2579 sshkey_froms(struct sshbuf *buf, struct sshkey **keyp) 2580 { 2581 struct sshbuf *b; 2582 int r; 2583 2584 if ((r = sshbuf_froms(buf, &b)) != 0) 2585 return r; 2586 r = sshkey_from_blob_internal(b, keyp, 1); 2587 sshbuf_free(b); 2588 return r; 2589 } 2590 2591 int 2592 sshkey_get_sigtype(const u_char *sig, size_t siglen, char **sigtypep) 2593 { 2594 int r; 2595 struct sshbuf *b = NULL; 2596 char *sigtype = NULL; 2597 2598 if (sigtypep != NULL) 2599 *sigtypep = NULL; 2600 if ((b = sshbuf_from(sig, siglen)) == NULL) 2601 return SSH_ERR_ALLOC_FAIL; 2602 if ((r = sshbuf_get_cstring(b, &sigtype, NULL)) != 0) 2603 goto out; 2604 /* success */ 2605 if (sigtypep != NULL) { 2606 *sigtypep = sigtype; 2607 sigtype = NULL; 2608 } 2609 r = 0; 2610 out: 2611 free(sigtype); 2612 sshbuf_free(b); 2613 return r; 2614 } 2615 2616 /* 2617 * 2618 * Checks whether a certificate's signature type is allowed. 2619 * Returns 0 (success) if the certificate signature type appears in the 2620 * "allowed" pattern-list, or the key is not a certificate to begin with. 2621 * Otherwise returns a ssherr.h code. 2622 */ 2623 int 2624 sshkey_check_cert_sigtype(const struct sshkey *key, const char *allowed) 2625 { 2626 if (key == NULL || allowed == NULL) 2627 return SSH_ERR_INVALID_ARGUMENT; 2628 if (!sshkey_type_is_cert(key->type)) 2629 return 0; 2630 if (key->cert == NULL || key->cert->signature_type == NULL) 2631 return SSH_ERR_INVALID_ARGUMENT; 2632 if (match_pattern_list(key->cert->signature_type, allowed, 0) != 1) 2633 return SSH_ERR_SIGN_ALG_UNSUPPORTED; 2634 return 0; 2635 } 2636 2637 /* 2638 * Returns the expected signature algorithm for a given public key algorithm. 2639 */ 2640 const char * 2641 sshkey_sigalg_by_name(const char *name) 2642 { 2643 const struct keytype *kt; 2644 2645 for (kt = keytypes; kt->type != -1; kt++) { 2646 if (strcmp(kt->name, name) != 0) 2647 continue; 2648 if (kt->sigalg != NULL) 2649 return kt->sigalg; 2650 if (!kt->cert) 2651 return kt->name; 2652 return sshkey_ssh_name_from_type_nid( 2653 sshkey_type_plain(kt->type), kt->nid); 2654 } 2655 return NULL; 2656 } 2657 2658 /* 2659 * Verifies that the signature algorithm appearing inside the signature blob 2660 * matches that which was requested. 2661 */ 2662 int 2663 sshkey_check_sigtype(const u_char *sig, size_t siglen, 2664 const char *requested_alg) 2665 { 2666 const char *expected_alg; 2667 char *sigtype = NULL; 2668 int r; 2669 2670 if (requested_alg == NULL) 2671 return 0; 2672 if ((expected_alg = sshkey_sigalg_by_name(requested_alg)) == NULL) 2673 return SSH_ERR_INVALID_ARGUMENT; 2674 if ((r = sshkey_get_sigtype(sig, siglen, &sigtype)) != 0) 2675 return r; 2676 r = strcmp(expected_alg, sigtype) == 0; 2677 free(sigtype); 2678 return r ? 0 : SSH_ERR_SIGN_ALG_UNSUPPORTED; 2679 } 2680 2681 int 2682 sshkey_sign(struct sshkey *key, 2683 u_char **sigp, size_t *lenp, 2684 const u_char *data, size_t datalen, 2685 const char *alg, const char *sk_provider, const char *sk_pin, u_int compat) 2686 { 2687 int was_shielded = sshkey_is_shielded(key); 2688 int r2, r = SSH_ERR_INTERNAL_ERROR; 2689 2690 if (sigp != NULL) 2691 *sigp = NULL; 2692 if (lenp != NULL) 2693 *lenp = 0; 2694 if (datalen > SSH_KEY_MAX_SIGN_DATA_SIZE) 2695 return SSH_ERR_INVALID_ARGUMENT; 2696 if ((r = sshkey_unshield_private(key)) != 0) 2697 return r; 2698 switch (key->type) { 2699 #ifdef WITH_OPENSSL 2700 case KEY_DSA_CERT: 2701 case KEY_DSA: 2702 r = ssh_dss_sign(key, sigp, lenp, data, datalen, compat); 2703 break; 2704 case KEY_ECDSA_CERT: 2705 case KEY_ECDSA: 2706 r = ssh_ecdsa_sign(key, sigp, lenp, data, datalen, compat); 2707 break; 2708 case KEY_RSA_CERT: 2709 case KEY_RSA: 2710 r = ssh_rsa_sign(key, sigp, lenp, data, datalen, alg); 2711 break; 2712 #endif /* WITH_OPENSSL */ 2713 case KEY_ED25519: 2714 case KEY_ED25519_CERT: 2715 r = ssh_ed25519_sign(key, sigp, lenp, data, datalen, compat); 2716 break; 2717 case KEY_ED25519_SK: 2718 case KEY_ED25519_SK_CERT: 2719 case KEY_ECDSA_SK_CERT: 2720 case KEY_ECDSA_SK: 2721 r = sshsk_sign(sk_provider, key, sigp, lenp, data, 2722 datalen, compat, sk_pin); 2723 break; 2724 #ifdef WITH_XMSS 2725 case KEY_XMSS: 2726 case KEY_XMSS_CERT: 2727 r = ssh_xmss_sign(key, sigp, lenp, data, datalen, compat); 2728 break; 2729 #endif /* WITH_XMSS */ 2730 default: 2731 r = SSH_ERR_KEY_TYPE_UNKNOWN; 2732 break; 2733 } 2734 if (was_shielded && (r2 = sshkey_shield_private(key)) != 0) 2735 return r2; 2736 return r; 2737 } 2738 2739 /* 2740 * ssh_key_verify returns 0 for a correct signature and < 0 on error. 2741 * If "alg" specified, then the signature must use that algorithm. 2742 */ 2743 int 2744 sshkey_verify(const struct sshkey *key, 2745 const u_char *sig, size_t siglen, 2746 const u_char *data, size_t dlen, const char *alg, u_int compat, 2747 struct sshkey_sig_details **detailsp) 2748 { 2749 if (detailsp != NULL) 2750 *detailsp = NULL; 2751 if (siglen == 0 || dlen > SSH_KEY_MAX_SIGN_DATA_SIZE) 2752 return SSH_ERR_INVALID_ARGUMENT; 2753 switch (key->type) { 2754 #ifdef WITH_OPENSSL 2755 case KEY_DSA_CERT: 2756 case KEY_DSA: 2757 return ssh_dss_verify(key, sig, siglen, data, dlen, compat); 2758 case KEY_ECDSA_CERT: 2759 case KEY_ECDSA: 2760 return ssh_ecdsa_verify(key, sig, siglen, data, dlen, compat); 2761 case KEY_ECDSA_SK_CERT: 2762 case KEY_ECDSA_SK: 2763 return ssh_ecdsa_sk_verify(key, sig, siglen, data, dlen, 2764 compat, detailsp); 2765 case KEY_RSA_CERT: 2766 case KEY_RSA: 2767 return ssh_rsa_verify(key, sig, siglen, data, dlen, alg); 2768 #endif /* WITH_OPENSSL */ 2769 case KEY_ED25519: 2770 case KEY_ED25519_CERT: 2771 return ssh_ed25519_verify(key, sig, siglen, data, dlen, compat); 2772 case KEY_ED25519_SK: 2773 case KEY_ED25519_SK_CERT: 2774 return ssh_ed25519_sk_verify(key, sig, siglen, data, dlen, 2775 compat, detailsp); 2776 #ifdef WITH_XMSS 2777 case KEY_XMSS: 2778 case KEY_XMSS_CERT: 2779 return ssh_xmss_verify(key, sig, siglen, data, dlen, compat); 2780 #endif /* WITH_XMSS */ 2781 default: 2782 return SSH_ERR_KEY_TYPE_UNKNOWN; 2783 } 2784 } 2785 2786 /* Convert a plain key to their _CERT equivalent */ 2787 int 2788 sshkey_to_certified(struct sshkey *k) 2789 { 2790 int newtype; 2791 2792 switch (k->type) { 2793 #ifdef WITH_OPENSSL 2794 case KEY_RSA: 2795 newtype = KEY_RSA_CERT; 2796 break; 2797 case KEY_DSA: 2798 newtype = KEY_DSA_CERT; 2799 break; 2800 case KEY_ECDSA: 2801 newtype = KEY_ECDSA_CERT; 2802 break; 2803 case KEY_ECDSA_SK: 2804 newtype = KEY_ECDSA_SK_CERT; 2805 break; 2806 #endif /* WITH_OPENSSL */ 2807 case KEY_ED25519_SK: 2808 newtype = KEY_ED25519_SK_CERT; 2809 break; 2810 case KEY_ED25519: 2811 newtype = KEY_ED25519_CERT; 2812 break; 2813 #ifdef WITH_XMSS 2814 case KEY_XMSS: 2815 newtype = KEY_XMSS_CERT; 2816 break; 2817 #endif /* WITH_XMSS */ 2818 default: 2819 return SSH_ERR_INVALID_ARGUMENT; 2820 } 2821 if ((k->cert = cert_new()) == NULL) 2822 return SSH_ERR_ALLOC_FAIL; 2823 k->type = newtype; 2824 return 0; 2825 } 2826 2827 /* Convert a certificate to its raw key equivalent */ 2828 int 2829 sshkey_drop_cert(struct sshkey *k) 2830 { 2831 if (!sshkey_type_is_cert(k->type)) 2832 return SSH_ERR_KEY_TYPE_UNKNOWN; 2833 cert_free(k->cert); 2834 k->cert = NULL; 2835 k->type = sshkey_type_plain(k->type); 2836 return 0; 2837 } 2838 2839 /* Sign a certified key, (re-)generating the signed certblob. */ 2840 int 2841 sshkey_certify_custom(struct sshkey *k, struct sshkey *ca, const char *alg, 2842 const char *sk_provider, const char *sk_pin, 2843 sshkey_certify_signer *signer, void *signer_ctx) 2844 { 2845 struct sshbuf *principals = NULL; 2846 u_char *ca_blob = NULL, *sig_blob = NULL, nonce[32]; 2847 size_t i, ca_len, sig_len; 2848 int ret = SSH_ERR_INTERNAL_ERROR; 2849 struct sshbuf *cert = NULL; 2850 char *sigtype = NULL; 2851 #ifdef WITH_OPENSSL 2852 const BIGNUM *rsa_n, *rsa_e, *dsa_p, *dsa_q, *dsa_g, *dsa_pub_key; 2853 #endif /* WITH_OPENSSL */ 2854 2855 if (k == NULL || k->cert == NULL || 2856 k->cert->certblob == NULL || ca == NULL) 2857 return SSH_ERR_INVALID_ARGUMENT; 2858 if (!sshkey_is_cert(k)) 2859 return SSH_ERR_KEY_TYPE_UNKNOWN; 2860 if (!sshkey_type_is_valid_ca(ca->type)) 2861 return SSH_ERR_KEY_CERT_INVALID_SIGN_KEY; 2862 2863 /* 2864 * If no alg specified as argument but a signature_type was set, 2865 * then prefer that. If both were specified, then they must match. 2866 */ 2867 if (alg == NULL) 2868 alg = k->cert->signature_type; 2869 else if (k->cert->signature_type != NULL && 2870 strcmp(alg, k->cert->signature_type) != 0) 2871 return SSH_ERR_INVALID_ARGUMENT; 2872 2873 /* 2874 * If no signing algorithm or signature_type was specified and we're 2875 * using a RSA key, then default to a good signature algorithm. 2876 */ 2877 if (alg == NULL && ca->type == KEY_RSA) 2878 alg = "rsa-sha2-512"; 2879 2880 if ((ret = sshkey_to_blob(ca, &ca_blob, &ca_len)) != 0) 2881 return SSH_ERR_KEY_CERT_INVALID_SIGN_KEY; 2882 2883 cert = k->cert->certblob; /* for readability */ 2884 sshbuf_reset(cert); 2885 if ((ret = sshbuf_put_cstring(cert, sshkey_ssh_name(k))) != 0) 2886 goto out; 2887 2888 /* -v01 certs put nonce first */ 2889 arc4random_buf(&nonce, sizeof(nonce)); 2890 if ((ret = sshbuf_put_string(cert, nonce, sizeof(nonce))) != 0) 2891 goto out; 2892 2893 /* XXX this substantially duplicates to_blob(); refactor */ 2894 switch (k->type) { 2895 #ifdef WITH_OPENSSL 2896 case KEY_DSA_CERT: 2897 DSA_get0_pqg(k->dsa, &dsa_p, &dsa_q, &dsa_g); 2898 DSA_get0_key(k->dsa, &dsa_pub_key, NULL); 2899 if ((ret = sshbuf_put_bignum2(cert, dsa_p)) != 0 || 2900 (ret = sshbuf_put_bignum2(cert, dsa_q)) != 0 || 2901 (ret = sshbuf_put_bignum2(cert, dsa_g)) != 0 || 2902 (ret = sshbuf_put_bignum2(cert, dsa_pub_key)) != 0) 2903 goto out; 2904 break; 2905 case KEY_ECDSA_CERT: 2906 case KEY_ECDSA_SK_CERT: 2907 if ((ret = sshbuf_put_cstring(cert, 2908 sshkey_curve_nid_to_name(k->ecdsa_nid))) != 0 || 2909 (ret = sshbuf_put_ec(cert, 2910 EC_KEY_get0_public_key(k->ecdsa), 2911 EC_KEY_get0_group(k->ecdsa))) != 0) 2912 goto out; 2913 if (k->type == KEY_ECDSA_SK_CERT) { 2914 if ((ret = sshbuf_put_cstring(cert, 2915 k->sk_application)) != 0) 2916 goto out; 2917 } 2918 break; 2919 case KEY_RSA_CERT: 2920 RSA_get0_key(k->rsa, &rsa_n, &rsa_e, NULL); 2921 if ((ret = sshbuf_put_bignum2(cert, rsa_e)) != 0 || 2922 (ret = sshbuf_put_bignum2(cert, rsa_n)) != 0) 2923 goto out; 2924 break; 2925 #endif /* WITH_OPENSSL */ 2926 case KEY_ED25519_CERT: 2927 case KEY_ED25519_SK_CERT: 2928 if ((ret = sshbuf_put_string(cert, 2929 k->ed25519_pk, ED25519_PK_SZ)) != 0) 2930 goto out; 2931 if (k->type == KEY_ED25519_SK_CERT) { 2932 if ((ret = sshbuf_put_cstring(cert, 2933 k->sk_application)) != 0) 2934 goto out; 2935 } 2936 break; 2937 #ifdef WITH_XMSS 2938 case KEY_XMSS_CERT: 2939 if (k->xmss_name == NULL) { 2940 ret = SSH_ERR_INVALID_ARGUMENT; 2941 goto out; 2942 } 2943 if ((ret = sshbuf_put_cstring(cert, k->xmss_name)) || 2944 (ret = sshbuf_put_string(cert, 2945 k->xmss_pk, sshkey_xmss_pklen(k))) != 0) 2946 goto out; 2947 break; 2948 #endif /* WITH_XMSS */ 2949 default: 2950 ret = SSH_ERR_INVALID_ARGUMENT; 2951 goto out; 2952 } 2953 2954 if ((ret = sshbuf_put_u64(cert, k->cert->serial)) != 0 || 2955 (ret = sshbuf_put_u32(cert, k->cert->type)) != 0 || 2956 (ret = sshbuf_put_cstring(cert, k->cert->key_id)) != 0) 2957 goto out; 2958 2959 if ((principals = sshbuf_new()) == NULL) { 2960 ret = SSH_ERR_ALLOC_FAIL; 2961 goto out; 2962 } 2963 for (i = 0; i < k->cert->nprincipals; i++) { 2964 if ((ret = sshbuf_put_cstring(principals, 2965 k->cert->principals[i])) != 0) 2966 goto out; 2967 } 2968 if ((ret = sshbuf_put_stringb(cert, principals)) != 0 || 2969 (ret = sshbuf_put_u64(cert, k->cert->valid_after)) != 0 || 2970 (ret = sshbuf_put_u64(cert, k->cert->valid_before)) != 0 || 2971 (ret = sshbuf_put_stringb(cert, k->cert->critical)) != 0 || 2972 (ret = sshbuf_put_stringb(cert, k->cert->extensions)) != 0 || 2973 (ret = sshbuf_put_string(cert, NULL, 0)) != 0 || /* Reserved */ 2974 (ret = sshbuf_put_string(cert, ca_blob, ca_len)) != 0) 2975 goto out; 2976 2977 /* Sign the whole mess */ 2978 if ((ret = signer(ca, &sig_blob, &sig_len, sshbuf_ptr(cert), 2979 sshbuf_len(cert), alg, sk_provider, sk_pin, 0, signer_ctx)) != 0) 2980 goto out; 2981 /* Check and update signature_type against what was actually used */ 2982 if ((ret = sshkey_get_sigtype(sig_blob, sig_len, &sigtype)) != 0) 2983 goto out; 2984 if (alg != NULL && strcmp(alg, sigtype) != 0) { 2985 ret = SSH_ERR_SIGN_ALG_UNSUPPORTED; 2986 goto out; 2987 } 2988 if (k->cert->signature_type == NULL) { 2989 k->cert->signature_type = sigtype; 2990 sigtype = NULL; 2991 } 2992 /* Append signature and we are done */ 2993 if ((ret = sshbuf_put_string(cert, sig_blob, sig_len)) != 0) 2994 goto out; 2995 ret = 0; 2996 out: 2997 if (ret != 0) 2998 sshbuf_reset(cert); 2999 free(sig_blob); 3000 free(ca_blob); 3001 free(sigtype); 3002 sshbuf_free(principals); 3003 return ret; 3004 } 3005 3006 static int 3007 default_key_sign(struct sshkey *key, u_char **sigp, size_t *lenp, 3008 const u_char *data, size_t datalen, 3009 const char *alg, const char *sk_provider, const char *sk_pin, 3010 u_int compat, void *ctx) 3011 { 3012 if (ctx != NULL) 3013 return SSH_ERR_INVALID_ARGUMENT; 3014 return sshkey_sign(key, sigp, lenp, data, datalen, alg, 3015 sk_provider, sk_pin, compat); 3016 } 3017 3018 int 3019 sshkey_certify(struct sshkey *k, struct sshkey *ca, const char *alg, 3020 const char *sk_provider, const char *sk_pin) 3021 { 3022 return sshkey_certify_custom(k, ca, alg, sk_provider, sk_pin, 3023 default_key_sign, NULL); 3024 } 3025 3026 int 3027 sshkey_cert_check_authority(const struct sshkey *k, 3028 int want_host, int require_principal, 3029 const char *name, const char **reason) 3030 { 3031 u_int i, principal_matches; 3032 time_t now = time(NULL); 3033 3034 if (reason == NULL) 3035 return SSH_ERR_INVALID_ARGUMENT; 3036 3037 if (want_host) { 3038 if (k->cert->type != SSH2_CERT_TYPE_HOST) { 3039 *reason = "Certificate invalid: not a host certificate"; 3040 return SSH_ERR_KEY_CERT_INVALID; 3041 } 3042 } else { 3043 if (k->cert->type != SSH2_CERT_TYPE_USER) { 3044 *reason = "Certificate invalid: not a user certificate"; 3045 return SSH_ERR_KEY_CERT_INVALID; 3046 } 3047 } 3048 if (now < 0) { 3049 /* yikes - system clock before epoch! */ 3050 *reason = "Certificate invalid: not yet valid"; 3051 return SSH_ERR_KEY_CERT_INVALID; 3052 } 3053 if ((u_int64_t)now < k->cert->valid_after) { 3054 *reason = "Certificate invalid: not yet valid"; 3055 return SSH_ERR_KEY_CERT_INVALID; 3056 } 3057 if ((u_int64_t)now >= k->cert->valid_before) { 3058 *reason = "Certificate invalid: expired"; 3059 return SSH_ERR_KEY_CERT_INVALID; 3060 } 3061 if (k->cert->nprincipals == 0) { 3062 if (require_principal) { 3063 *reason = "Certificate lacks principal list"; 3064 return SSH_ERR_KEY_CERT_INVALID; 3065 } 3066 } else if (name != NULL) { 3067 principal_matches = 0; 3068 for (i = 0; i < k->cert->nprincipals; i++) { 3069 if (strcmp(name, k->cert->principals[i]) == 0) { 3070 principal_matches = 1; 3071 break; 3072 } 3073 } 3074 if (!principal_matches) { 3075 *reason = "Certificate invalid: name is not a listed " 3076 "principal"; 3077 return SSH_ERR_KEY_CERT_INVALID; 3078 } 3079 } 3080 return 0; 3081 } 3082 3083 size_t 3084 sshkey_format_cert_validity(const struct sshkey_cert *cert, char *s, size_t l) 3085 { 3086 char from[32], to[32], ret[64]; 3087 time_t tt; 3088 struct tm *tm; 3089 3090 *from = *to = '\0'; 3091 if (cert->valid_after == 0 && 3092 cert->valid_before == 0xffffffffffffffffULL) 3093 return strlcpy(s, "forever", l); 3094 3095 if (cert->valid_after != 0) { 3096 /* XXX revisit INT_MAX in 2038 :) */ 3097 tt = cert->valid_after > INT_MAX ? 3098 INT_MAX : cert->valid_after; 3099 tm = localtime(&tt); 3100 strftime(from, sizeof(from), "%Y-%m-%dT%H:%M:%S", tm); 3101 } 3102 if (cert->valid_before != 0xffffffffffffffffULL) { 3103 /* XXX revisit INT_MAX in 2038 :) */ 3104 tt = cert->valid_before > INT_MAX ? 3105 INT_MAX : cert->valid_before; 3106 tm = localtime(&tt); 3107 strftime(to, sizeof(to), "%Y-%m-%dT%H:%M:%S", tm); 3108 } 3109 3110 if (cert->valid_after == 0) 3111 snprintf(ret, sizeof(ret), "before %s", to); 3112 else if (cert->valid_before == 0xffffffffffffffffULL) 3113 snprintf(ret, sizeof(ret), "after %s", from); 3114 else 3115 snprintf(ret, sizeof(ret), "from %s to %s", from, to); 3116 3117 return strlcpy(s, ret, l); 3118 } 3119 3120 int 3121 sshkey_private_serialize_opt(struct sshkey *key, struct sshbuf *buf, 3122 enum sshkey_serialize_rep opts) 3123 { 3124 int r = SSH_ERR_INTERNAL_ERROR; 3125 int was_shielded = sshkey_is_shielded(key); 3126 struct sshbuf *b = NULL; 3127 #ifdef WITH_OPENSSL 3128 const BIGNUM *rsa_n, *rsa_e, *rsa_d, *rsa_iqmp, *rsa_p, *rsa_q; 3129 const BIGNUM *dsa_p, *dsa_q, *dsa_g, *dsa_pub_key, *dsa_priv_key; 3130 #endif /* WITH_OPENSSL */ 3131 3132 if ((r = sshkey_unshield_private(key)) != 0) 3133 return r; 3134 if ((b = sshbuf_new()) == NULL) 3135 return SSH_ERR_ALLOC_FAIL; 3136 if ((r = sshbuf_put_cstring(b, sshkey_ssh_name(key))) != 0) 3137 goto out; 3138 switch (key->type) { 3139 #ifdef WITH_OPENSSL 3140 case KEY_RSA: 3141 RSA_get0_key(key->rsa, &rsa_n, &rsa_e, &rsa_d); 3142 RSA_get0_factors(key->rsa, &rsa_p, &rsa_q); 3143 RSA_get0_crt_params(key->rsa, NULL, NULL, &rsa_iqmp); 3144 if ((r = sshbuf_put_bignum2(b, rsa_n)) != 0 || 3145 (r = sshbuf_put_bignum2(b, rsa_e)) != 0 || 3146 (r = sshbuf_put_bignum2(b, rsa_d)) != 0 || 3147 (r = sshbuf_put_bignum2(b, rsa_iqmp)) != 0 || 3148 (r = sshbuf_put_bignum2(b, rsa_p)) != 0 || 3149 (r = sshbuf_put_bignum2(b, rsa_q)) != 0) 3150 goto out; 3151 break; 3152 case KEY_RSA_CERT: 3153 if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) { 3154 r = SSH_ERR_INVALID_ARGUMENT; 3155 goto out; 3156 } 3157 RSA_get0_key(key->rsa, NULL, NULL, &rsa_d); 3158 RSA_get0_factors(key->rsa, &rsa_p, &rsa_q); 3159 RSA_get0_crt_params(key->rsa, NULL, NULL, &rsa_iqmp); 3160 if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 || 3161 (r = sshbuf_put_bignum2(b, rsa_d)) != 0 || 3162 (r = sshbuf_put_bignum2(b, rsa_iqmp)) != 0 || 3163 (r = sshbuf_put_bignum2(b, rsa_p)) != 0 || 3164 (r = sshbuf_put_bignum2(b, rsa_q)) != 0) 3165 goto out; 3166 break; 3167 case KEY_DSA: 3168 DSA_get0_pqg(key->dsa, &dsa_p, &dsa_q, &dsa_g); 3169 DSA_get0_key(key->dsa, &dsa_pub_key, &dsa_priv_key); 3170 if ((r = sshbuf_put_bignum2(b, dsa_p)) != 0 || 3171 (r = sshbuf_put_bignum2(b, dsa_q)) != 0 || 3172 (r = sshbuf_put_bignum2(b, dsa_g)) != 0 || 3173 (r = sshbuf_put_bignum2(b, dsa_pub_key)) != 0 || 3174 (r = sshbuf_put_bignum2(b, dsa_priv_key)) != 0) 3175 goto out; 3176 break; 3177 case KEY_DSA_CERT: 3178 if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) { 3179 r = SSH_ERR_INVALID_ARGUMENT; 3180 goto out; 3181 } 3182 DSA_get0_key(key->dsa, NULL, &dsa_priv_key); 3183 if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 || 3184 (r = sshbuf_put_bignum2(b, dsa_priv_key)) != 0) 3185 goto out; 3186 break; 3187 case KEY_ECDSA: 3188 if ((r = sshbuf_put_cstring(b, 3189 sshkey_curve_nid_to_name(key->ecdsa_nid))) != 0 || 3190 (r = sshbuf_put_eckey(b, key->ecdsa)) != 0 || 3191 (r = sshbuf_put_bignum2(b, 3192 EC_KEY_get0_private_key(key->ecdsa))) != 0) 3193 goto out; 3194 break; 3195 case KEY_ECDSA_CERT: 3196 if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) { 3197 r = SSH_ERR_INVALID_ARGUMENT; 3198 goto out; 3199 } 3200 if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 || 3201 (r = sshbuf_put_bignum2(b, 3202 EC_KEY_get0_private_key(key->ecdsa))) != 0) 3203 goto out; 3204 break; 3205 case KEY_ECDSA_SK: 3206 if ((r = sshbuf_put_cstring(b, 3207 sshkey_curve_nid_to_name(key->ecdsa_nid))) != 0 || 3208 (r = sshbuf_put_eckey(b, key->ecdsa)) != 0 || 3209 (r = sshbuf_put_cstring(b, key->sk_application)) != 0 || 3210 (r = sshbuf_put_u8(b, key->sk_flags)) != 0 || 3211 (r = sshbuf_put_stringb(b, key->sk_key_handle)) != 0 || 3212 (r = sshbuf_put_stringb(b, key->sk_reserved)) != 0) 3213 goto out; 3214 break; 3215 case KEY_ECDSA_SK_CERT: 3216 if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) { 3217 r = SSH_ERR_INVALID_ARGUMENT; 3218 goto out; 3219 } 3220 if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 || 3221 (r = sshbuf_put_cstring(b, key->sk_application)) != 0 || 3222 (r = sshbuf_put_u8(b, key->sk_flags)) != 0 || 3223 (r = sshbuf_put_stringb(b, key->sk_key_handle)) != 0 || 3224 (r = sshbuf_put_stringb(b, key->sk_reserved)) != 0) 3225 goto out; 3226 break; 3227 #endif /* WITH_OPENSSL */ 3228 case KEY_ED25519: 3229 if ((r = sshbuf_put_string(b, key->ed25519_pk, 3230 ED25519_PK_SZ)) != 0 || 3231 (r = sshbuf_put_string(b, key->ed25519_sk, 3232 ED25519_SK_SZ)) != 0) 3233 goto out; 3234 break; 3235 case KEY_ED25519_CERT: 3236 if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) { 3237 r = SSH_ERR_INVALID_ARGUMENT; 3238 goto out; 3239 } 3240 if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 || 3241 (r = sshbuf_put_string(b, key->ed25519_pk, 3242 ED25519_PK_SZ)) != 0 || 3243 (r = sshbuf_put_string(b, key->ed25519_sk, 3244 ED25519_SK_SZ)) != 0) 3245 goto out; 3246 break; 3247 case KEY_ED25519_SK: 3248 if ((r = sshbuf_put_string(b, key->ed25519_pk, 3249 ED25519_PK_SZ)) != 0 || 3250 (r = sshbuf_put_cstring(b, key->sk_application)) != 0 || 3251 (r = sshbuf_put_u8(b, key->sk_flags)) != 0 || 3252 (r = sshbuf_put_stringb(b, key->sk_key_handle)) != 0 || 3253 (r = sshbuf_put_stringb(b, key->sk_reserved)) != 0) 3254 goto out; 3255 break; 3256 case KEY_ED25519_SK_CERT: 3257 if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) { 3258 r = SSH_ERR_INVALID_ARGUMENT; 3259 goto out; 3260 } 3261 if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 || 3262 (r = sshbuf_put_string(b, key->ed25519_pk, 3263 ED25519_PK_SZ)) != 0 || 3264 (r = sshbuf_put_cstring(b, key->sk_application)) != 0 || 3265 (r = sshbuf_put_u8(b, key->sk_flags)) != 0 || 3266 (r = sshbuf_put_stringb(b, key->sk_key_handle)) != 0 || 3267 (r = sshbuf_put_stringb(b, key->sk_reserved)) != 0) 3268 goto out; 3269 break; 3270 #ifdef WITH_XMSS 3271 case KEY_XMSS: 3272 if (key->xmss_name == NULL) { 3273 r = SSH_ERR_INVALID_ARGUMENT; 3274 goto out; 3275 } 3276 if ((r = sshbuf_put_cstring(b, key->xmss_name)) != 0 || 3277 (r = sshbuf_put_string(b, key->xmss_pk, 3278 sshkey_xmss_pklen(key))) != 0 || 3279 (r = sshbuf_put_string(b, key->xmss_sk, 3280 sshkey_xmss_sklen(key))) != 0 || 3281 (r = sshkey_xmss_serialize_state_opt(key, b, opts)) != 0) 3282 goto out; 3283 break; 3284 case KEY_XMSS_CERT: 3285 if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0 || 3286 key->xmss_name == NULL) { 3287 r = SSH_ERR_INVALID_ARGUMENT; 3288 goto out; 3289 } 3290 if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 || 3291 (r = sshbuf_put_cstring(b, key->xmss_name)) != 0 || 3292 (r = sshbuf_put_string(b, key->xmss_pk, 3293 sshkey_xmss_pklen(key))) != 0 || 3294 (r = sshbuf_put_string(b, key->xmss_sk, 3295 sshkey_xmss_sklen(key))) != 0 || 3296 (r = sshkey_xmss_serialize_state_opt(key, b, opts)) != 0) 3297 goto out; 3298 break; 3299 #endif /* WITH_XMSS */ 3300 default: 3301 r = SSH_ERR_INVALID_ARGUMENT; 3302 goto out; 3303 } 3304 /* 3305 * success (but we still need to append the output to buf after 3306 * possibly re-shielding the private key) 3307 */ 3308 r = 0; 3309 out: 3310 if (was_shielded) 3311 r = sshkey_shield_private(key); 3312 if (r == 0) 3313 r = sshbuf_putb(buf, b); 3314 sshbuf_free(b); 3315 3316 return r; 3317 } 3318 3319 int 3320 sshkey_private_serialize(struct sshkey *key, struct sshbuf *b) 3321 { 3322 return sshkey_private_serialize_opt(key, b, 3323 SSHKEY_SERIALIZE_DEFAULT); 3324 } 3325 3326 int 3327 sshkey_private_deserialize(struct sshbuf *buf, struct sshkey **kp) 3328 { 3329 char *tname = NULL, *curve = NULL, *xmss_name = NULL; 3330 struct sshkey *k = NULL; 3331 size_t pklen = 0, sklen = 0; 3332 int type, r = SSH_ERR_INTERNAL_ERROR; 3333 u_char *ed25519_pk = NULL, *ed25519_sk = NULL; 3334 u_char *xmss_pk = NULL, *xmss_sk = NULL; 3335 #ifdef WITH_OPENSSL 3336 BIGNUM *exponent = NULL; 3337 BIGNUM *rsa_n = NULL, *rsa_e = NULL, *rsa_d = NULL; 3338 BIGNUM *rsa_iqmp = NULL, *rsa_p = NULL, *rsa_q = NULL; 3339 BIGNUM *dsa_p = NULL, *dsa_q = NULL, *dsa_g = NULL; 3340 BIGNUM *dsa_pub_key = NULL, *dsa_priv_key = NULL; 3341 #endif /* WITH_OPENSSL */ 3342 3343 if (kp != NULL) 3344 *kp = NULL; 3345 if ((r = sshbuf_get_cstring(buf, &tname, NULL)) != 0) 3346 goto out; 3347 type = sshkey_type_from_name(tname); 3348 if (sshkey_type_is_cert(type)) { 3349 /* 3350 * Certificate key private keys begin with the certificate 3351 * itself. Make sure this matches the type of the enclosing 3352 * private key. 3353 */ 3354 if ((r = sshkey_froms(buf, &k)) != 0) 3355 goto out; 3356 if (k->type != type) { 3357 r = SSH_ERR_KEY_CERT_MISMATCH; 3358 goto out; 3359 } 3360 /* For ECDSA keys, the group must match too */ 3361 if (k->type == KEY_ECDSA && 3362 k->ecdsa_nid != sshkey_ecdsa_nid_from_name(tname)) { 3363 r = SSH_ERR_KEY_CERT_MISMATCH; 3364 goto out; 3365 } 3366 } else { 3367 if ((k = sshkey_new(type)) == NULL) { 3368 r = SSH_ERR_ALLOC_FAIL; 3369 goto out; 3370 } 3371 } 3372 switch (type) { 3373 #ifdef WITH_OPENSSL 3374 case KEY_DSA: 3375 if ((r = sshbuf_get_bignum2(buf, &dsa_p)) != 0 || 3376 (r = sshbuf_get_bignum2(buf, &dsa_q)) != 0 || 3377 (r = sshbuf_get_bignum2(buf, &dsa_g)) != 0 || 3378 (r = sshbuf_get_bignum2(buf, &dsa_pub_key)) != 0) 3379 goto out; 3380 if (!DSA_set0_pqg(k->dsa, dsa_p, dsa_q, dsa_g)) { 3381 r = SSH_ERR_LIBCRYPTO_ERROR; 3382 goto out; 3383 } 3384 dsa_p = dsa_q = dsa_g = NULL; /* transferred */ 3385 if (!DSA_set0_key(k->dsa, dsa_pub_key, NULL)) { 3386 r = SSH_ERR_LIBCRYPTO_ERROR; 3387 goto out; 3388 } 3389 dsa_pub_key = NULL; /* transferred */ 3390 /* FALLTHROUGH */ 3391 case KEY_DSA_CERT: 3392 if ((r = sshbuf_get_bignum2(buf, &dsa_priv_key)) != 0) 3393 goto out; 3394 if (!DSA_set0_key(k->dsa, NULL, dsa_priv_key)) { 3395 r = SSH_ERR_LIBCRYPTO_ERROR; 3396 goto out; 3397 } 3398 dsa_priv_key = NULL; /* transferred */ 3399 break; 3400 case KEY_ECDSA: 3401 if ((k->ecdsa_nid = sshkey_ecdsa_nid_from_name(tname)) == -1) { 3402 r = SSH_ERR_INVALID_ARGUMENT; 3403 goto out; 3404 } 3405 if ((r = sshbuf_get_cstring(buf, &curve, NULL)) != 0) 3406 goto out; 3407 if (k->ecdsa_nid != sshkey_curve_name_to_nid(curve)) { 3408 r = SSH_ERR_EC_CURVE_MISMATCH; 3409 goto out; 3410 } 3411 k->ecdsa = EC_KEY_new_by_curve_name(k->ecdsa_nid); 3412 if (k->ecdsa == NULL) { 3413 r = SSH_ERR_LIBCRYPTO_ERROR; 3414 goto out; 3415 } 3416 if ((r = sshbuf_get_eckey(buf, k->ecdsa)) != 0) 3417 goto out; 3418 /* FALLTHROUGH */ 3419 case KEY_ECDSA_CERT: 3420 if ((r = sshbuf_get_bignum2(buf, &exponent)) != 0) 3421 goto out; 3422 if (EC_KEY_set_private_key(k->ecdsa, exponent) != 1) { 3423 r = SSH_ERR_LIBCRYPTO_ERROR; 3424 goto out; 3425 } 3426 if ((r = sshkey_ec_validate_public(EC_KEY_get0_group(k->ecdsa), 3427 EC_KEY_get0_public_key(k->ecdsa))) != 0 || 3428 (r = sshkey_ec_validate_private(k->ecdsa)) != 0) 3429 goto out; 3430 break; 3431 case KEY_ECDSA_SK: 3432 if ((k->ecdsa_nid = sshkey_ecdsa_nid_from_name(tname)) == -1) { 3433 r = SSH_ERR_INVALID_ARGUMENT; 3434 goto out; 3435 } 3436 if ((r = sshbuf_get_cstring(buf, &curve, NULL)) != 0) 3437 goto out; 3438 if (k->ecdsa_nid != sshkey_curve_name_to_nid(curve)) { 3439 r = SSH_ERR_EC_CURVE_MISMATCH; 3440 goto out; 3441 } 3442 if ((k->sk_key_handle = sshbuf_new()) == NULL || 3443 (k->sk_reserved = sshbuf_new()) == NULL) { 3444 r = SSH_ERR_ALLOC_FAIL; 3445 goto out; 3446 } 3447 k->ecdsa = EC_KEY_new_by_curve_name(k->ecdsa_nid); 3448 if (k->ecdsa == NULL) { 3449 r = SSH_ERR_LIBCRYPTO_ERROR; 3450 goto out; 3451 } 3452 if ((r = sshbuf_get_eckey(buf, k->ecdsa)) != 0 || 3453 (r = sshbuf_get_cstring(buf, &k->sk_application, 3454 NULL)) != 0 || 3455 (r = sshbuf_get_u8(buf, &k->sk_flags)) != 0 || 3456 (r = sshbuf_get_stringb(buf, k->sk_key_handle)) != 0 || 3457 (r = sshbuf_get_stringb(buf, k->sk_reserved)) != 0) 3458 goto out; 3459 if ((r = sshkey_ec_validate_public(EC_KEY_get0_group(k->ecdsa), 3460 EC_KEY_get0_public_key(k->ecdsa))) != 0) 3461 goto out; 3462 break; 3463 case KEY_ECDSA_SK_CERT: 3464 if ((k->sk_key_handle = sshbuf_new()) == NULL || 3465 (k->sk_reserved = sshbuf_new()) == NULL) { 3466 r = SSH_ERR_ALLOC_FAIL; 3467 goto out; 3468 } 3469 if ((r = sshbuf_get_cstring(buf, &k->sk_application, 3470 NULL)) != 0 || 3471 (r = sshbuf_get_u8(buf, &k->sk_flags)) != 0 || 3472 (r = sshbuf_get_stringb(buf, k->sk_key_handle)) != 0 || 3473 (r = sshbuf_get_stringb(buf, k->sk_reserved)) != 0) 3474 goto out; 3475 if ((r = sshkey_ec_validate_public(EC_KEY_get0_group(k->ecdsa), 3476 EC_KEY_get0_public_key(k->ecdsa))) != 0) 3477 goto out; 3478 break; 3479 case KEY_RSA: 3480 if ((r = sshbuf_get_bignum2(buf, &rsa_n)) != 0 || 3481 (r = sshbuf_get_bignum2(buf, &rsa_e)) != 0) 3482 goto out; 3483 if (!RSA_set0_key(k->rsa, rsa_n, rsa_e, NULL)) { 3484 r = SSH_ERR_LIBCRYPTO_ERROR; 3485 goto out; 3486 } 3487 rsa_n = rsa_e = NULL; /* transferred */ 3488 /* FALLTHROUGH */ 3489 case KEY_RSA_CERT: 3490 if ((r = sshbuf_get_bignum2(buf, &rsa_d)) != 0 || 3491 (r = sshbuf_get_bignum2(buf, &rsa_iqmp)) != 0 || 3492 (r = sshbuf_get_bignum2(buf, &rsa_p)) != 0 || 3493 (r = sshbuf_get_bignum2(buf, &rsa_q)) != 0) 3494 goto out; 3495 if (!RSA_set0_key(k->rsa, NULL, NULL, rsa_d)) { 3496 r = SSH_ERR_LIBCRYPTO_ERROR; 3497 goto out; 3498 } 3499 rsa_d = NULL; /* transferred */ 3500 if (!RSA_set0_factors(k->rsa, rsa_p, rsa_q)) { 3501 r = SSH_ERR_LIBCRYPTO_ERROR; 3502 goto out; 3503 } 3504 rsa_p = rsa_q = NULL; /* transferred */ 3505 if ((r = check_rsa_length(k->rsa)) != 0) 3506 goto out; 3507 if ((r = ssh_rsa_complete_crt_parameters(k, rsa_iqmp)) != 0) 3508 goto out; 3509 break; 3510 #endif /* WITH_OPENSSL */ 3511 case KEY_ED25519: 3512 case KEY_ED25519_CERT: 3513 if ((r = sshbuf_get_string(buf, &ed25519_pk, &pklen)) != 0 || 3514 (r = sshbuf_get_string(buf, &ed25519_sk, &sklen)) != 0) 3515 goto out; 3516 if (pklen != ED25519_PK_SZ || sklen != ED25519_SK_SZ) { 3517 r = SSH_ERR_INVALID_FORMAT; 3518 goto out; 3519 } 3520 k->ed25519_pk = ed25519_pk; 3521 k->ed25519_sk = ed25519_sk; 3522 ed25519_pk = ed25519_sk = NULL; /* transferred */ 3523 break; 3524 case KEY_ED25519_SK: 3525 case KEY_ED25519_SK_CERT: 3526 if ((r = sshbuf_get_string(buf, &ed25519_pk, &pklen)) != 0) 3527 goto out; 3528 if (pklen != ED25519_PK_SZ) { 3529 r = SSH_ERR_INVALID_FORMAT; 3530 goto out; 3531 } 3532 if ((k->sk_key_handle = sshbuf_new()) == NULL || 3533 (k->sk_reserved = sshbuf_new()) == NULL) { 3534 r = SSH_ERR_ALLOC_FAIL; 3535 goto out; 3536 } 3537 if ((r = sshbuf_get_cstring(buf, &k->sk_application, 3538 NULL)) != 0 || 3539 (r = sshbuf_get_u8(buf, &k->sk_flags)) != 0 || 3540 (r = sshbuf_get_stringb(buf, k->sk_key_handle)) != 0 || 3541 (r = sshbuf_get_stringb(buf, k->sk_reserved)) != 0) 3542 goto out; 3543 k->ed25519_pk = ed25519_pk; 3544 ed25519_pk = NULL; /* transferred */ 3545 break; 3546 #ifdef WITH_XMSS 3547 case KEY_XMSS: 3548 case KEY_XMSS_CERT: 3549 if ((r = sshbuf_get_cstring(buf, &xmss_name, NULL)) != 0 || 3550 (r = sshbuf_get_string(buf, &xmss_pk, &pklen)) != 0 || 3551 (r = sshbuf_get_string(buf, &xmss_sk, &sklen)) != 0) 3552 goto out; 3553 if (type == KEY_XMSS && 3554 (r = sshkey_xmss_init(k, xmss_name)) != 0) 3555 goto out; 3556 if (pklen != sshkey_xmss_pklen(k) || 3557 sklen != sshkey_xmss_sklen(k)) { 3558 r = SSH_ERR_INVALID_FORMAT; 3559 goto out; 3560 } 3561 k->xmss_pk = xmss_pk; 3562 k->xmss_sk = xmss_sk; 3563 xmss_pk = xmss_sk = NULL; 3564 /* optional internal state */ 3565 if ((r = sshkey_xmss_deserialize_state_opt(k, buf)) != 0) 3566 goto out; 3567 break; 3568 #endif /* WITH_XMSS */ 3569 default: 3570 r = SSH_ERR_KEY_TYPE_UNKNOWN; 3571 goto out; 3572 } 3573 #ifdef WITH_OPENSSL 3574 /* enable blinding */ 3575 switch (k->type) { 3576 case KEY_RSA: 3577 case KEY_RSA_CERT: 3578 if (RSA_blinding_on(k->rsa, NULL) != 1) { 3579 r = SSH_ERR_LIBCRYPTO_ERROR; 3580 goto out; 3581 } 3582 break; 3583 } 3584 #endif /* WITH_OPENSSL */ 3585 /* success */ 3586 r = 0; 3587 if (kp != NULL) { 3588 *kp = k; 3589 k = NULL; 3590 } 3591 out: 3592 free(tname); 3593 free(curve); 3594 #ifdef WITH_OPENSSL 3595 BN_clear_free(exponent); 3596 BN_clear_free(dsa_p); 3597 BN_clear_free(dsa_q); 3598 BN_clear_free(dsa_g); 3599 BN_clear_free(dsa_pub_key); 3600 BN_clear_free(dsa_priv_key); 3601 BN_clear_free(rsa_n); 3602 BN_clear_free(rsa_e); 3603 BN_clear_free(rsa_d); 3604 BN_clear_free(rsa_p); 3605 BN_clear_free(rsa_q); 3606 BN_clear_free(rsa_iqmp); 3607 #endif /* WITH_OPENSSL */ 3608 sshkey_free(k); 3609 freezero(ed25519_pk, pklen); 3610 freezero(ed25519_sk, sklen); 3611 free(xmss_name); 3612 freezero(xmss_pk, pklen); 3613 freezero(xmss_sk, sklen); 3614 return r; 3615 } 3616 3617 #ifdef WITH_OPENSSL 3618 int 3619 sshkey_ec_validate_public(const EC_GROUP *group, const EC_POINT *public) 3620 { 3621 EC_POINT *nq = NULL; 3622 BIGNUM *order = NULL, *x = NULL, *y = NULL, *tmp = NULL; 3623 int ret = SSH_ERR_KEY_INVALID_EC_VALUE; 3624 3625 /* 3626 * NB. This assumes OpenSSL has already verified that the public 3627 * point lies on the curve. This is done by EC_POINT_oct2point() 3628 * implicitly calling EC_POINT_is_on_curve(). If this code is ever 3629 * reachable with public points not unmarshalled using 3630 * EC_POINT_oct2point then the caller will need to explicitly check. 3631 */ 3632 3633 /* 3634 * We shouldn't ever hit this case because bignum_get_ecpoint() 3635 * refuses to load GF2m points. 3636 */ 3637 if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) != 3638 NID_X9_62_prime_field) 3639 goto out; 3640 3641 /* Q != infinity */ 3642 if (EC_POINT_is_at_infinity(group, public)) 3643 goto out; 3644 3645 if ((x = BN_new()) == NULL || 3646 (y = BN_new()) == NULL || 3647 (order = BN_new()) == NULL || 3648 (tmp = BN_new()) == NULL) { 3649 ret = SSH_ERR_ALLOC_FAIL; 3650 goto out; 3651 } 3652 3653 /* log2(x) > log2(order)/2, log2(y) > log2(order)/2 */ 3654 if (EC_GROUP_get_order(group, order, NULL) != 1 || 3655 EC_POINT_get_affine_coordinates_GFp(group, public, 3656 x, y, NULL) != 1) { 3657 ret = SSH_ERR_LIBCRYPTO_ERROR; 3658 goto out; 3659 } 3660 if (BN_num_bits(x) <= BN_num_bits(order) / 2 || 3661 BN_num_bits(y) <= BN_num_bits(order) / 2) 3662 goto out; 3663 3664 /* nQ == infinity (n == order of subgroup) */ 3665 if ((nq = EC_POINT_new(group)) == NULL) { 3666 ret = SSH_ERR_ALLOC_FAIL; 3667 goto out; 3668 } 3669 if (EC_POINT_mul(group, nq, NULL, public, order, NULL) != 1) { 3670 ret = SSH_ERR_LIBCRYPTO_ERROR; 3671 goto out; 3672 } 3673 if (EC_POINT_is_at_infinity(group, nq) != 1) 3674 goto out; 3675 3676 /* x < order - 1, y < order - 1 */ 3677 if (!BN_sub(tmp, order, BN_value_one())) { 3678 ret = SSH_ERR_LIBCRYPTO_ERROR; 3679 goto out; 3680 } 3681 if (BN_cmp(x, tmp) >= 0 || BN_cmp(y, tmp) >= 0) 3682 goto out; 3683 ret = 0; 3684 out: 3685 BN_clear_free(x); 3686 BN_clear_free(y); 3687 BN_clear_free(order); 3688 BN_clear_free(tmp); 3689 EC_POINT_free(nq); 3690 return ret; 3691 } 3692 3693 int 3694 sshkey_ec_validate_private(const EC_KEY *key) 3695 { 3696 BIGNUM *order = NULL, *tmp = NULL; 3697 int ret = SSH_ERR_KEY_INVALID_EC_VALUE; 3698 3699 if ((order = BN_new()) == NULL || (tmp = BN_new()) == NULL) { 3700 ret = SSH_ERR_ALLOC_FAIL; 3701 goto out; 3702 } 3703 3704 /* log2(private) > log2(order)/2 */ 3705 if (EC_GROUP_get_order(EC_KEY_get0_group(key), order, NULL) != 1) { 3706 ret = SSH_ERR_LIBCRYPTO_ERROR; 3707 goto out; 3708 } 3709 if (BN_num_bits(EC_KEY_get0_private_key(key)) <= 3710 BN_num_bits(order) / 2) 3711 goto out; 3712 3713 /* private < order - 1 */ 3714 if (!BN_sub(tmp, order, BN_value_one())) { 3715 ret = SSH_ERR_LIBCRYPTO_ERROR; 3716 goto out; 3717 } 3718 if (BN_cmp(EC_KEY_get0_private_key(key), tmp) >= 0) 3719 goto out; 3720 ret = 0; 3721 out: 3722 BN_clear_free(order); 3723 BN_clear_free(tmp); 3724 return ret; 3725 } 3726 3727 void 3728 sshkey_dump_ec_point(const EC_GROUP *group, const EC_POINT *point) 3729 { 3730 BIGNUM *x = NULL, *y = NULL; 3731 3732 if (point == NULL) { 3733 fputs("point=(NULL)\n", stderr); 3734 return; 3735 } 3736 if ((x = BN_new()) == NULL || (y = BN_new()) == NULL) { 3737 fprintf(stderr, "%s: BN_new failed\n", __func__); 3738 goto out; 3739 } 3740 if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) != 3741 NID_X9_62_prime_field) { 3742 fprintf(stderr, "%s: group is not a prime field\n", __func__); 3743 goto out; 3744 } 3745 if (EC_POINT_get_affine_coordinates_GFp(group, point, 3746 x, y, NULL) != 1) { 3747 fprintf(stderr, "%s: EC_POINT_get_affine_coordinates_GFp\n", 3748 __func__); 3749 goto out; 3750 } 3751 fputs("x=", stderr); 3752 BN_print_fp(stderr, x); 3753 fputs("\ny=", stderr); 3754 BN_print_fp(stderr, y); 3755 fputs("\n", stderr); 3756 out: 3757 BN_clear_free(x); 3758 BN_clear_free(y); 3759 } 3760 3761 void 3762 sshkey_dump_ec_key(const EC_KEY *key) 3763 { 3764 const BIGNUM *exponent; 3765 3766 sshkey_dump_ec_point(EC_KEY_get0_group(key), 3767 EC_KEY_get0_public_key(key)); 3768 fputs("exponent=", stderr); 3769 if ((exponent = EC_KEY_get0_private_key(key)) == NULL) 3770 fputs("(NULL)", stderr); 3771 else 3772 BN_print_fp(stderr, EC_KEY_get0_private_key(key)); 3773 fputs("\n", stderr); 3774 } 3775 #endif /* WITH_OPENSSL */ 3776 3777 static int 3778 sshkey_private_to_blob2(struct sshkey *prv, struct sshbuf *blob, 3779 const char *passphrase, const char *comment, const char *ciphername, 3780 int rounds) 3781 { 3782 u_char *cp, *key = NULL, *pubkeyblob = NULL; 3783 u_char salt[SALT_LEN]; 3784 char *b64 = NULL; 3785 size_t i, pubkeylen, keylen, ivlen, blocksize, authlen; 3786 u_int check; 3787 int r = SSH_ERR_INTERNAL_ERROR; 3788 struct sshcipher_ctx *ciphercontext = NULL; 3789 const struct sshcipher *cipher; 3790 const char *kdfname = KDFNAME; 3791 struct sshbuf *encoded = NULL, *encrypted = NULL, *kdf = NULL; 3792 3793 if (rounds <= 0) 3794 rounds = DEFAULT_ROUNDS; 3795 if (passphrase == NULL || !strlen(passphrase)) { 3796 ciphername = "none"; 3797 kdfname = "none"; 3798 } else if (ciphername == NULL) 3799 ciphername = DEFAULT_CIPHERNAME; 3800 if ((cipher = cipher_by_name(ciphername)) == NULL) { 3801 r = SSH_ERR_INVALID_ARGUMENT; 3802 goto out; 3803 } 3804 3805 if ((kdf = sshbuf_new()) == NULL || 3806 (encoded = sshbuf_new()) == NULL || 3807 (encrypted = sshbuf_new()) == NULL) { 3808 r = SSH_ERR_ALLOC_FAIL; 3809 goto out; 3810 } 3811 blocksize = cipher_blocksize(cipher); 3812 keylen = cipher_keylen(cipher); 3813 ivlen = cipher_ivlen(cipher); 3814 authlen = cipher_authlen(cipher); 3815 if ((key = calloc(1, keylen + ivlen)) == NULL) { 3816 r = SSH_ERR_ALLOC_FAIL; 3817 goto out; 3818 } 3819 if (strcmp(kdfname, "bcrypt") == 0) { 3820 arc4random_buf(salt, SALT_LEN); 3821 if (bcrypt_pbkdf(passphrase, strlen(passphrase), 3822 salt, SALT_LEN, key, keylen + ivlen, rounds) < 0) { 3823 r = SSH_ERR_INVALID_ARGUMENT; 3824 goto out; 3825 } 3826 if ((r = sshbuf_put_string(kdf, salt, SALT_LEN)) != 0 || 3827 (r = sshbuf_put_u32(kdf, rounds)) != 0) 3828 goto out; 3829 } else if (strcmp(kdfname, "none") != 0) { 3830 /* Unsupported KDF type */ 3831 r = SSH_ERR_KEY_UNKNOWN_CIPHER; 3832 goto out; 3833 } 3834 if ((r = cipher_init(&ciphercontext, cipher, key, keylen, 3835 key + keylen, ivlen, 1)) != 0) 3836 goto out; 3837 3838 if ((r = sshbuf_put(encoded, AUTH_MAGIC, sizeof(AUTH_MAGIC))) != 0 || 3839 (r = sshbuf_put_cstring(encoded, ciphername)) != 0 || 3840 (r = sshbuf_put_cstring(encoded, kdfname)) != 0 || 3841 (r = sshbuf_put_stringb(encoded, kdf)) != 0 || 3842 (r = sshbuf_put_u32(encoded, 1)) != 0 || /* number of keys */ 3843 (r = sshkey_to_blob(prv, &pubkeyblob, &pubkeylen)) != 0 || 3844 (r = sshbuf_put_string(encoded, pubkeyblob, pubkeylen)) != 0) 3845 goto out; 3846 3847 /* set up the buffer that will be encrypted */ 3848 3849 /* Random check bytes */ 3850 check = arc4random(); 3851 if ((r = sshbuf_put_u32(encrypted, check)) != 0 || 3852 (r = sshbuf_put_u32(encrypted, check)) != 0) 3853 goto out; 3854 3855 /* append private key and comment*/ 3856 if ((r = sshkey_private_serialize_opt(prv, encrypted, 3857 SSHKEY_SERIALIZE_FULL)) != 0 || 3858 (r = sshbuf_put_cstring(encrypted, comment)) != 0) 3859 goto out; 3860 3861 /* padding */ 3862 i = 0; 3863 while (sshbuf_len(encrypted) % blocksize) { 3864 if ((r = sshbuf_put_u8(encrypted, ++i & 0xff)) != 0) 3865 goto out; 3866 } 3867 3868 /* length in destination buffer */ 3869 if ((r = sshbuf_put_u32(encoded, sshbuf_len(encrypted))) != 0) 3870 goto out; 3871 3872 /* encrypt */ 3873 if ((r = sshbuf_reserve(encoded, 3874 sshbuf_len(encrypted) + authlen, &cp)) != 0) 3875 goto out; 3876 if ((r = cipher_crypt(ciphercontext, 0, cp, 3877 sshbuf_ptr(encrypted), sshbuf_len(encrypted), 0, authlen)) != 0) 3878 goto out; 3879 3880 sshbuf_reset(blob); 3881 3882 /* assemble uuencoded key */ 3883 if ((r = sshbuf_put(blob, MARK_BEGIN, MARK_BEGIN_LEN)) != 0 || 3884 (r = sshbuf_dtob64(encoded, blob, 1)) != 0 || 3885 (r = sshbuf_put(blob, MARK_END, MARK_END_LEN)) != 0) 3886 goto out; 3887 3888 /* success */ 3889 r = 0; 3890 3891 out: 3892 sshbuf_free(kdf); 3893 sshbuf_free(encoded); 3894 sshbuf_free(encrypted); 3895 cipher_free(ciphercontext); 3896 explicit_bzero(salt, sizeof(salt)); 3897 if (key != NULL) 3898 freezero(key, keylen + ivlen); 3899 if (pubkeyblob != NULL) 3900 freezero(pubkeyblob, pubkeylen); 3901 if (b64 != NULL) 3902 freezero(b64, strlen(b64)); 3903 return r; 3904 } 3905 3906 static int 3907 private2_uudecode(struct sshbuf *blob, struct sshbuf **decodedp) 3908 { 3909 const u_char *cp; 3910 size_t encoded_len; 3911 int r; 3912 u_char last; 3913 struct sshbuf *encoded = NULL, *decoded = NULL; 3914 3915 if (blob == NULL || decodedp == NULL) 3916 return SSH_ERR_INVALID_ARGUMENT; 3917 3918 *decodedp = NULL; 3919 3920 if ((encoded = sshbuf_new()) == NULL || 3921 (decoded = sshbuf_new()) == NULL) { 3922 r = SSH_ERR_ALLOC_FAIL; 3923 goto out; 3924 } 3925 3926 /* check preamble */ 3927 cp = sshbuf_ptr(blob); 3928 encoded_len = sshbuf_len(blob); 3929 if (encoded_len < (MARK_BEGIN_LEN + MARK_END_LEN) || 3930 memcmp(cp, MARK_BEGIN, MARK_BEGIN_LEN) != 0) { 3931 r = SSH_ERR_INVALID_FORMAT; 3932 goto out; 3933 } 3934 cp += MARK_BEGIN_LEN; 3935 encoded_len -= MARK_BEGIN_LEN; 3936 3937 /* Look for end marker, removing whitespace as we go */ 3938 while (encoded_len > 0) { 3939 if (*cp != '\n' && *cp != '\r') { 3940 if ((r = sshbuf_put_u8(encoded, *cp)) != 0) 3941 goto out; 3942 } 3943 last = *cp; 3944 encoded_len--; 3945 cp++; 3946 if (last == '\n') { 3947 if (encoded_len >= MARK_END_LEN && 3948 memcmp(cp, MARK_END, MARK_END_LEN) == 0) { 3949 /* \0 terminate */ 3950 if ((r = sshbuf_put_u8(encoded, 0)) != 0) 3951 goto out; 3952 break; 3953 } 3954 } 3955 } 3956 if (encoded_len == 0) { 3957 r = SSH_ERR_INVALID_FORMAT; 3958 goto out; 3959 } 3960 3961 /* decode base64 */ 3962 if ((r = sshbuf_b64tod(decoded, (char *)sshbuf_ptr(encoded))) != 0) 3963 goto out; 3964 3965 /* check magic */ 3966 if (sshbuf_len(decoded) < sizeof(AUTH_MAGIC) || 3967 memcmp(sshbuf_ptr(decoded), AUTH_MAGIC, sizeof(AUTH_MAGIC))) { 3968 r = SSH_ERR_INVALID_FORMAT; 3969 goto out; 3970 } 3971 /* success */ 3972 *decodedp = decoded; 3973 decoded = NULL; 3974 r = 0; 3975 out: 3976 sshbuf_free(encoded); 3977 sshbuf_free(decoded); 3978 return r; 3979 } 3980 3981 static int 3982 private2_decrypt(struct sshbuf *decoded, const char *passphrase, 3983 struct sshbuf **decryptedp, struct sshkey **pubkeyp) 3984 { 3985 char *ciphername = NULL, *kdfname = NULL; 3986 const struct sshcipher *cipher = NULL; 3987 int r = SSH_ERR_INTERNAL_ERROR; 3988 size_t keylen = 0, ivlen = 0, authlen = 0, slen = 0; 3989 struct sshbuf *kdf = NULL, *decrypted = NULL; 3990 struct sshcipher_ctx *ciphercontext = NULL; 3991 struct sshkey *pubkey = NULL; 3992 u_char *key = NULL, *salt = NULL, *dp; 3993 u_int blocksize, rounds, nkeys, encrypted_len, check1, check2; 3994 3995 if (decoded == NULL || decryptedp == NULL || pubkeyp == NULL) 3996 return SSH_ERR_INVALID_ARGUMENT; 3997 3998 *decryptedp = NULL; 3999 *pubkeyp = NULL; 4000 4001 if ((decrypted = sshbuf_new()) == NULL) { 4002 r = SSH_ERR_ALLOC_FAIL; 4003 goto out; 4004 } 4005 4006 /* parse public portion of key */ 4007 if ((r = sshbuf_consume(decoded, sizeof(AUTH_MAGIC))) != 0 || 4008 (r = sshbuf_get_cstring(decoded, &ciphername, NULL)) != 0 || 4009 (r = sshbuf_get_cstring(decoded, &kdfname, NULL)) != 0 || 4010 (r = sshbuf_froms(decoded, &kdf)) != 0 || 4011 (r = sshbuf_get_u32(decoded, &nkeys)) != 0) 4012 goto out; 4013 4014 if (nkeys != 1) { 4015 /* XXX only one key supported at present */ 4016 r = SSH_ERR_INVALID_FORMAT; 4017 goto out; 4018 } 4019 4020 if ((r = sshkey_froms(decoded, &pubkey)) != 0 || 4021 (r = sshbuf_get_u32(decoded, &encrypted_len)) != 0) 4022 goto out; 4023 4024 if ((cipher = cipher_by_name(ciphername)) == NULL) { 4025 r = SSH_ERR_KEY_UNKNOWN_CIPHER; 4026 goto out; 4027 } 4028 if (strcmp(kdfname, "none") != 0 && strcmp(kdfname, "bcrypt") != 0) { 4029 r = SSH_ERR_KEY_UNKNOWN_CIPHER; 4030 goto out; 4031 } 4032 if (strcmp(kdfname, "none") == 0 && strcmp(ciphername, "none") != 0) { 4033 r = SSH_ERR_INVALID_FORMAT; 4034 goto out; 4035 } 4036 if ((passphrase == NULL || strlen(passphrase) == 0) && 4037 strcmp(kdfname, "none") != 0) { 4038 /* passphrase required */ 4039 r = SSH_ERR_KEY_WRONG_PASSPHRASE; 4040 goto out; 4041 } 4042 4043 /* check size of encrypted key blob */ 4044 blocksize = cipher_blocksize(cipher); 4045 if (encrypted_len < blocksize || (encrypted_len % blocksize) != 0) { 4046 r = SSH_ERR_INVALID_FORMAT; 4047 goto out; 4048 } 4049 4050 /* setup key */ 4051 keylen = cipher_keylen(cipher); 4052 ivlen = cipher_ivlen(cipher); 4053 authlen = cipher_authlen(cipher); 4054 if ((key = calloc(1, keylen + ivlen)) == NULL) { 4055 r = SSH_ERR_ALLOC_FAIL; 4056 goto out; 4057 } 4058 if (strcmp(kdfname, "bcrypt") == 0) { 4059 if ((r = sshbuf_get_string(kdf, &salt, &slen)) != 0 || 4060 (r = sshbuf_get_u32(kdf, &rounds)) != 0) 4061 goto out; 4062 if (bcrypt_pbkdf(passphrase, strlen(passphrase), salt, slen, 4063 key, keylen + ivlen, rounds) < 0) { 4064 r = SSH_ERR_INVALID_FORMAT; 4065 goto out; 4066 } 4067 } 4068 4069 /* check that an appropriate amount of auth data is present */ 4070 if (sshbuf_len(decoded) < authlen || 4071 sshbuf_len(decoded) - authlen < encrypted_len) { 4072 r = SSH_ERR_INVALID_FORMAT; 4073 goto out; 4074 } 4075 4076 /* decrypt private portion of key */ 4077 if ((r = sshbuf_reserve(decrypted, encrypted_len, &dp)) != 0 || 4078 (r = cipher_init(&ciphercontext, cipher, key, keylen, 4079 key + keylen, ivlen, 0)) != 0) 4080 goto out; 4081 if ((r = cipher_crypt(ciphercontext, 0, dp, sshbuf_ptr(decoded), 4082 encrypted_len, 0, authlen)) != 0) { 4083 /* an integrity error here indicates an incorrect passphrase */ 4084 if (r == SSH_ERR_MAC_INVALID) 4085 r = SSH_ERR_KEY_WRONG_PASSPHRASE; 4086 goto out; 4087 } 4088 if ((r = sshbuf_consume(decoded, encrypted_len + authlen)) != 0) 4089 goto out; 4090 /* there should be no trailing data */ 4091 if (sshbuf_len(decoded) != 0) { 4092 r = SSH_ERR_INVALID_FORMAT; 4093 goto out; 4094 } 4095 4096 /* check check bytes */ 4097 if ((r = sshbuf_get_u32(decrypted, &check1)) != 0 || 4098 (r = sshbuf_get_u32(decrypted, &check2)) != 0) 4099 goto out; 4100 if (check1 != check2) { 4101 r = SSH_ERR_KEY_WRONG_PASSPHRASE; 4102 goto out; 4103 } 4104 /* success */ 4105 *decryptedp = decrypted; 4106 decrypted = NULL; 4107 *pubkeyp = pubkey; 4108 pubkey = NULL; 4109 r = 0; 4110 out: 4111 cipher_free(ciphercontext); 4112 free(ciphername); 4113 free(kdfname); 4114 sshkey_free(pubkey); 4115 if (salt != NULL) { 4116 explicit_bzero(salt, slen); 4117 free(salt); 4118 } 4119 if (key != NULL) { 4120 explicit_bzero(key, keylen + ivlen); 4121 free(key); 4122 } 4123 sshbuf_free(kdf); 4124 sshbuf_free(decrypted); 4125 return r; 4126 } 4127 4128 /* Check deterministic padding after private key */ 4129 static int 4130 private2_check_padding(struct sshbuf *decrypted) 4131 { 4132 u_char pad; 4133 size_t i; 4134 int r = SSH_ERR_INTERNAL_ERROR; 4135 4136 i = 0; 4137 while (sshbuf_len(decrypted)) { 4138 if ((r = sshbuf_get_u8(decrypted, &pad)) != 0) 4139 goto out; 4140 if (pad != (++i & 0xff)) { 4141 r = SSH_ERR_INVALID_FORMAT; 4142 goto out; 4143 } 4144 } 4145 /* success */ 4146 r = 0; 4147 out: 4148 explicit_bzero(&pad, sizeof(pad)); 4149 explicit_bzero(&i, sizeof(i)); 4150 return r; 4151 } 4152 4153 static int 4154 sshkey_parse_private2(struct sshbuf *blob, int type, const char *passphrase, 4155 struct sshkey **keyp, char **commentp) 4156 { 4157 char *comment = NULL; 4158 int r = SSH_ERR_INTERNAL_ERROR; 4159 struct sshbuf *decoded = NULL, *decrypted = NULL; 4160 struct sshkey *k = NULL, *pubkey = NULL; 4161 4162 if (keyp != NULL) 4163 *keyp = NULL; 4164 if (commentp != NULL) 4165 *commentp = NULL; 4166 4167 /* Undo base64 encoding and decrypt the private section */ 4168 if ((r = private2_uudecode(blob, &decoded)) != 0 || 4169 (r = private2_decrypt(decoded, passphrase, 4170 &decrypted, &pubkey)) != 0) 4171 goto out; 4172 4173 if (type != KEY_UNSPEC && 4174 sshkey_type_plain(type) != sshkey_type_plain(pubkey->type)) { 4175 r = SSH_ERR_KEY_TYPE_MISMATCH; 4176 goto out; 4177 } 4178 4179 /* Load the private key and comment */ 4180 if ((r = sshkey_private_deserialize(decrypted, &k)) != 0 || 4181 (r = sshbuf_get_cstring(decrypted, &comment, NULL)) != 0) 4182 goto out; 4183 4184 /* Check deterministic padding after private section */ 4185 if ((r = private2_check_padding(decrypted)) != 0) 4186 goto out; 4187 4188 /* Check that the public key in the envelope matches the private key */ 4189 if (!sshkey_equal(pubkey, k)) { 4190 r = SSH_ERR_INVALID_FORMAT; 4191 goto out; 4192 } 4193 4194 /* success */ 4195 r = 0; 4196 if (keyp != NULL) { 4197 *keyp = k; 4198 k = NULL; 4199 } 4200 if (commentp != NULL) { 4201 *commentp = comment; 4202 comment = NULL; 4203 } 4204 out: 4205 free(comment); 4206 sshbuf_free(decoded); 4207 sshbuf_free(decrypted); 4208 sshkey_free(k); 4209 sshkey_free(pubkey); 4210 return r; 4211 } 4212 4213 static int 4214 sshkey_parse_private2_pubkey(struct sshbuf *blob, int type, 4215 struct sshkey **keyp) 4216 { 4217 int r = SSH_ERR_INTERNAL_ERROR; 4218 struct sshbuf *decoded = NULL; 4219 struct sshkey *pubkey = NULL; 4220 u_int nkeys = 0; 4221 4222 if (keyp != NULL) 4223 *keyp = NULL; 4224 4225 if ((r = private2_uudecode(blob, &decoded)) != 0) 4226 goto out; 4227 /* parse public key from unencrypted envelope */ 4228 if ((r = sshbuf_consume(decoded, sizeof(AUTH_MAGIC))) != 0 || 4229 (r = sshbuf_skip_string(decoded)) != 0 || /* cipher */ 4230 (r = sshbuf_skip_string(decoded)) != 0 || /* KDF alg */ 4231 (r = sshbuf_skip_string(decoded)) != 0 || /* KDF hint */ 4232 (r = sshbuf_get_u32(decoded, &nkeys)) != 0) 4233 goto out; 4234 4235 if (nkeys != 1) { 4236 /* XXX only one key supported at present */ 4237 r = SSH_ERR_INVALID_FORMAT; 4238 goto out; 4239 } 4240 4241 /* Parse the public key */ 4242 if ((r = sshkey_froms(decoded, &pubkey)) != 0) 4243 goto out; 4244 4245 if (type != KEY_UNSPEC && 4246 sshkey_type_plain(type) != sshkey_type_plain(pubkey->type)) { 4247 r = SSH_ERR_KEY_TYPE_MISMATCH; 4248 goto out; 4249 } 4250 4251 /* success */ 4252 r = 0; 4253 if (keyp != NULL) { 4254 *keyp = pubkey; 4255 pubkey = NULL; 4256 } 4257 out: 4258 sshbuf_free(decoded); 4259 sshkey_free(pubkey); 4260 return r; 4261 } 4262 4263 #ifdef WITH_OPENSSL 4264 /* convert SSH v2 key to PEM or PKCS#8 format */ 4265 static int 4266 sshkey_private_to_blob_pem_pkcs8(struct sshkey *key, struct sshbuf *buf, 4267 int format, const char *_passphrase, const char *comment) 4268 { 4269 int was_shielded = sshkey_is_shielded(key); 4270 int success, r; 4271 int blen, len = strlen(_passphrase); 4272 u_char *passphrase = (len > 0) ? (u_char *)_passphrase : NULL; 4273 const EVP_CIPHER *cipher = (len > 0) ? EVP_aes_128_cbc() : NULL; 4274 char *bptr; 4275 BIO *bio = NULL; 4276 struct sshbuf *blob; 4277 EVP_PKEY *pkey = NULL; 4278 4279 if (len > 0 && len <= 4) 4280 return SSH_ERR_PASSPHRASE_TOO_SHORT; 4281 if ((blob = sshbuf_new()) == NULL) 4282 return SSH_ERR_ALLOC_FAIL; 4283 if ((bio = BIO_new(BIO_s_mem())) == NULL) { 4284 r = SSH_ERR_ALLOC_FAIL; 4285 goto out; 4286 } 4287 if (format == SSHKEY_PRIVATE_PKCS8 && (pkey = EVP_PKEY_new()) == NULL) { 4288 r = SSH_ERR_ALLOC_FAIL; 4289 goto out; 4290 } 4291 if ((r = sshkey_unshield_private(key)) != 0) 4292 goto out; 4293 4294 switch (key->type) { 4295 case KEY_DSA: 4296 if (format == SSHKEY_PRIVATE_PEM) { 4297 success = PEM_write_bio_DSAPrivateKey(bio, key->dsa, 4298 cipher, passphrase, len, NULL, NULL); 4299 } else { 4300 success = EVP_PKEY_set1_DSA(pkey, key->dsa); 4301 } 4302 break; 4303 case KEY_ECDSA: 4304 if (format == SSHKEY_PRIVATE_PEM) { 4305 success = PEM_write_bio_ECPrivateKey(bio, key->ecdsa, 4306 cipher, passphrase, len, NULL, NULL); 4307 } else { 4308 success = EVP_PKEY_set1_EC_KEY(pkey, key->ecdsa); 4309 } 4310 break; 4311 case KEY_RSA: 4312 if (format == SSHKEY_PRIVATE_PEM) { 4313 success = PEM_write_bio_RSAPrivateKey(bio, key->rsa, 4314 cipher, passphrase, len, NULL, NULL); 4315 } else { 4316 success = EVP_PKEY_set1_RSA(pkey, key->rsa); 4317 } 4318 break; 4319 default: 4320 success = 0; 4321 break; 4322 } 4323 if (success == 0) { 4324 r = SSH_ERR_LIBCRYPTO_ERROR; 4325 goto out; 4326 } 4327 if (format == SSHKEY_PRIVATE_PKCS8) { 4328 if ((success = PEM_write_bio_PrivateKey(bio, pkey, cipher, 4329 passphrase, len, NULL, NULL)) == 0) { 4330 r = SSH_ERR_LIBCRYPTO_ERROR; 4331 goto out; 4332 } 4333 } 4334 if ((blen = BIO_get_mem_data(bio, &bptr)) <= 0) { 4335 r = SSH_ERR_INTERNAL_ERROR; 4336 goto out; 4337 } 4338 if ((r = sshbuf_put(blob, bptr, blen)) != 0) 4339 goto out; 4340 r = 0; 4341 out: 4342 if (was_shielded) 4343 r = sshkey_shield_private(key); 4344 if (r == 0) 4345 r = sshbuf_putb(buf, blob); 4346 4347 EVP_PKEY_free(pkey); 4348 sshbuf_free(blob); 4349 BIO_free(bio); 4350 return r; 4351 } 4352 #endif /* WITH_OPENSSL */ 4353 4354 /* Serialise "key" to buffer "blob" */ 4355 int 4356 sshkey_private_to_fileblob(struct sshkey *key, struct sshbuf *blob, 4357 const char *passphrase, const char *comment, 4358 int format, const char *openssh_format_cipher, int openssh_format_rounds) 4359 { 4360 switch (key->type) { 4361 #ifdef WITH_OPENSSL 4362 case KEY_DSA: 4363 case KEY_ECDSA: 4364 case KEY_RSA: 4365 break; /* see below */ 4366 #endif /* WITH_OPENSSL */ 4367 case KEY_ED25519: 4368 case KEY_ED25519_SK: 4369 #ifdef WITH_XMSS 4370 case KEY_XMSS: 4371 #endif /* WITH_XMSS */ 4372 #ifdef WITH_OPENSSL 4373 case KEY_ECDSA_SK: 4374 #endif /* WITH_OPENSSL */ 4375 return sshkey_private_to_blob2(key, blob, passphrase, 4376 comment, openssh_format_cipher, openssh_format_rounds); 4377 default: 4378 return SSH_ERR_KEY_TYPE_UNKNOWN; 4379 } 4380 4381 #ifdef WITH_OPENSSL 4382 switch (format) { 4383 case SSHKEY_PRIVATE_OPENSSH: 4384 return sshkey_private_to_blob2(key, blob, passphrase, 4385 comment, openssh_format_cipher, openssh_format_rounds); 4386 case SSHKEY_PRIVATE_PEM: 4387 case SSHKEY_PRIVATE_PKCS8: 4388 return sshkey_private_to_blob_pem_pkcs8(key, blob, 4389 format, passphrase, comment); 4390 default: 4391 return SSH_ERR_INVALID_ARGUMENT; 4392 } 4393 #endif /* WITH_OPENSSL */ 4394 } 4395 4396 #ifdef WITH_OPENSSL 4397 static int 4398 translate_libcrypto_error(unsigned long pem_err) 4399 { 4400 int pem_reason = ERR_GET_REASON(pem_err); 4401 4402 switch (ERR_GET_LIB(pem_err)) { 4403 case ERR_LIB_PEM: 4404 switch (pem_reason) { 4405 case PEM_R_BAD_PASSWORD_READ: 4406 case PEM_R_PROBLEMS_GETTING_PASSWORD: 4407 case PEM_R_BAD_DECRYPT: 4408 return SSH_ERR_KEY_WRONG_PASSPHRASE; 4409 default: 4410 return SSH_ERR_INVALID_FORMAT; 4411 } 4412 case ERR_LIB_EVP: 4413 switch (pem_reason) { 4414 case EVP_R_BAD_DECRYPT: 4415 return SSH_ERR_KEY_WRONG_PASSPHRASE; 4416 #ifdef EVP_R_BN_DECODE_ERROR 4417 case EVP_R_BN_DECODE_ERROR: 4418 #endif 4419 case EVP_R_DECODE_ERROR: 4420 #ifdef EVP_R_PRIVATE_KEY_DECODE_ERROR 4421 case EVP_R_PRIVATE_KEY_DECODE_ERROR: 4422 #endif 4423 return SSH_ERR_INVALID_FORMAT; 4424 default: 4425 return SSH_ERR_LIBCRYPTO_ERROR; 4426 } 4427 case ERR_LIB_ASN1: 4428 return SSH_ERR_INVALID_FORMAT; 4429 } 4430 return SSH_ERR_LIBCRYPTO_ERROR; 4431 } 4432 4433 static void 4434 clear_libcrypto_errors(void) 4435 { 4436 while (ERR_get_error() != 0) 4437 ; 4438 } 4439 4440 /* 4441 * Translate OpenSSL error codes to determine whether 4442 * passphrase is required/incorrect. 4443 */ 4444 static int 4445 convert_libcrypto_error(void) 4446 { 4447 /* 4448 * Some password errors are reported at the beginning 4449 * of the error queue. 4450 */ 4451 if (translate_libcrypto_error(ERR_peek_error()) == 4452 SSH_ERR_KEY_WRONG_PASSPHRASE) 4453 return SSH_ERR_KEY_WRONG_PASSPHRASE; 4454 return translate_libcrypto_error(ERR_peek_last_error()); 4455 } 4456 4457 static int 4458 sshkey_parse_private_pem_fileblob(struct sshbuf *blob, int type, 4459 const char *passphrase, struct sshkey **keyp) 4460 { 4461 EVP_PKEY *pk = NULL; 4462 struct sshkey *prv = NULL; 4463 BIO *bio = NULL; 4464 int r; 4465 4466 if (keyp != NULL) 4467 *keyp = NULL; 4468 4469 if ((bio = BIO_new(BIO_s_mem())) == NULL || sshbuf_len(blob) > INT_MAX) 4470 return SSH_ERR_ALLOC_FAIL; 4471 if (BIO_write(bio, sshbuf_ptr(blob), sshbuf_len(blob)) != 4472 (int)sshbuf_len(blob)) { 4473 r = SSH_ERR_ALLOC_FAIL; 4474 goto out; 4475 } 4476 4477 clear_libcrypto_errors(); 4478 if ((pk = PEM_read_bio_PrivateKey(bio, NULL, NULL, 4479 (char *)passphrase)) == NULL) { 4480 /* 4481 * libcrypto may return various ASN.1 errors when attempting 4482 * to parse a key with an incorrect passphrase. 4483 * Treat all format errors as "incorrect passphrase" if a 4484 * passphrase was supplied. 4485 */ 4486 if (passphrase != NULL && *passphrase != '\0') 4487 r = SSH_ERR_KEY_WRONG_PASSPHRASE; 4488 else 4489 r = convert_libcrypto_error(); 4490 goto out; 4491 } 4492 if (EVP_PKEY_base_id(pk) == EVP_PKEY_RSA && 4493 (type == KEY_UNSPEC || type == KEY_RSA)) { 4494 if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) { 4495 r = SSH_ERR_ALLOC_FAIL; 4496 goto out; 4497 } 4498 prv->rsa = EVP_PKEY_get1_RSA(pk); 4499 prv->type = KEY_RSA; 4500 #ifdef DEBUG_PK 4501 RSA_print_fp(stderr, prv->rsa, 8); 4502 #endif 4503 if (RSA_blinding_on(prv->rsa, NULL) != 1) { 4504 r = SSH_ERR_LIBCRYPTO_ERROR; 4505 goto out; 4506 } 4507 if ((r = check_rsa_length(prv->rsa)) != 0) 4508 goto out; 4509 } else if (EVP_PKEY_base_id(pk) == EVP_PKEY_DSA && 4510 (type == KEY_UNSPEC || type == KEY_DSA)) { 4511 if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) { 4512 r = SSH_ERR_ALLOC_FAIL; 4513 goto out; 4514 } 4515 prv->dsa = EVP_PKEY_get1_DSA(pk); 4516 prv->type = KEY_DSA; 4517 #ifdef DEBUG_PK 4518 DSA_print_fp(stderr, prv->dsa, 8); 4519 #endif 4520 } else if (EVP_PKEY_base_id(pk) == EVP_PKEY_EC && 4521 (type == KEY_UNSPEC || type == KEY_ECDSA)) { 4522 if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) { 4523 r = SSH_ERR_ALLOC_FAIL; 4524 goto out; 4525 } 4526 prv->ecdsa = EVP_PKEY_get1_EC_KEY(pk); 4527 prv->type = KEY_ECDSA; 4528 prv->ecdsa_nid = sshkey_ecdsa_key_to_nid(prv->ecdsa); 4529 if (prv->ecdsa_nid == -1 || 4530 sshkey_curve_nid_to_name(prv->ecdsa_nid) == NULL || 4531 sshkey_ec_validate_public(EC_KEY_get0_group(prv->ecdsa), 4532 EC_KEY_get0_public_key(prv->ecdsa)) != 0 || 4533 sshkey_ec_validate_private(prv->ecdsa) != 0) { 4534 r = SSH_ERR_INVALID_FORMAT; 4535 goto out; 4536 } 4537 #ifdef DEBUG_PK 4538 if (prv != NULL && prv->ecdsa != NULL) 4539 sshkey_dump_ec_key(prv->ecdsa); 4540 #endif 4541 } else { 4542 r = SSH_ERR_INVALID_FORMAT; 4543 goto out; 4544 } 4545 r = 0; 4546 if (keyp != NULL) { 4547 *keyp = prv; 4548 prv = NULL; 4549 } 4550 out: 4551 BIO_free(bio); 4552 EVP_PKEY_free(pk); 4553 sshkey_free(prv); 4554 return r; 4555 } 4556 #endif /* WITH_OPENSSL */ 4557 4558 int 4559 sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type, 4560 const char *passphrase, struct sshkey **keyp, char **commentp) 4561 { 4562 int r = SSH_ERR_INTERNAL_ERROR; 4563 4564 if (keyp != NULL) 4565 *keyp = NULL; 4566 if (commentp != NULL) 4567 *commentp = NULL; 4568 4569 switch (type) { 4570 case KEY_ED25519: 4571 case KEY_XMSS: 4572 /* No fallback for new-format-only keys */ 4573 return sshkey_parse_private2(blob, type, passphrase, 4574 keyp, commentp); 4575 default: 4576 r = sshkey_parse_private2(blob, type, passphrase, keyp, 4577 commentp); 4578 /* Only fallback to PEM parser if a format error occurred. */ 4579 if (r != SSH_ERR_INVALID_FORMAT) 4580 return r; 4581 #ifdef WITH_OPENSSL 4582 return sshkey_parse_private_pem_fileblob(blob, type, 4583 passphrase, keyp); 4584 #else 4585 return SSH_ERR_INVALID_FORMAT; 4586 #endif /* WITH_OPENSSL */ 4587 } 4588 } 4589 4590 int 4591 sshkey_parse_private_fileblob(struct sshbuf *buffer, const char *passphrase, 4592 struct sshkey **keyp, char **commentp) 4593 { 4594 if (keyp != NULL) 4595 *keyp = NULL; 4596 if (commentp != NULL) 4597 *commentp = NULL; 4598 4599 return sshkey_parse_private_fileblob_type(buffer, KEY_UNSPEC, 4600 passphrase, keyp, commentp); 4601 } 4602 4603 void 4604 sshkey_sig_details_free(struct sshkey_sig_details *details) 4605 { 4606 freezero(details, sizeof(*details)); 4607 } 4608 4609 int 4610 sshkey_parse_pubkey_from_private_fileblob_type(struct sshbuf *blob, int type, 4611 struct sshkey **pubkeyp) 4612 { 4613 int r = SSH_ERR_INTERNAL_ERROR; 4614 4615 if (pubkeyp != NULL) 4616 *pubkeyp = NULL; 4617 /* only new-format private keys bundle a public key inside */ 4618 if ((r = sshkey_parse_private2_pubkey(blob, type, pubkeyp)) != 0) 4619 return r; 4620 return 0; 4621 } 4622 4623 #ifdef WITH_XMSS 4624 /* 4625 * serialize the key with the current state and forward the state 4626 * maxsign times. 4627 */ 4628 int 4629 sshkey_private_serialize_maxsign(struct sshkey *k, struct sshbuf *b, 4630 u_int32_t maxsign, int printerror) 4631 { 4632 int r, rupdate; 4633 4634 if (maxsign == 0 || 4635 sshkey_type_plain(k->type) != KEY_XMSS) 4636 return sshkey_private_serialize_opt(k, b, 4637 SSHKEY_SERIALIZE_DEFAULT); 4638 if ((r = sshkey_xmss_get_state(k, printerror)) != 0 || 4639 (r = sshkey_private_serialize_opt(k, b, 4640 SSHKEY_SERIALIZE_STATE)) != 0 || 4641 (r = sshkey_xmss_forward_state(k, maxsign)) != 0) 4642 goto out; 4643 r = 0; 4644 out: 4645 if ((rupdate = sshkey_xmss_update_state(k, printerror)) != 0) { 4646 if (r == 0) 4647 r = rupdate; 4648 } 4649 return r; 4650 } 4651 4652 u_int32_t 4653 sshkey_signatures_left(const struct sshkey *k) 4654 { 4655 if (sshkey_type_plain(k->type) == KEY_XMSS) 4656 return sshkey_xmss_signatures_left(k); 4657 return 0; 4658 } 4659 4660 int 4661 sshkey_enable_maxsign(struct sshkey *k, u_int32_t maxsign) 4662 { 4663 if (sshkey_type_plain(k->type) != KEY_XMSS) 4664 return SSH_ERR_INVALID_ARGUMENT; 4665 return sshkey_xmss_enable_maxsign(k, maxsign); 4666 } 4667 4668 int 4669 sshkey_set_filename(struct sshkey *k, const char *filename) 4670 { 4671 if (k == NULL) 4672 return SSH_ERR_INVALID_ARGUMENT; 4673 if (sshkey_type_plain(k->type) != KEY_XMSS) 4674 return 0; 4675 if (filename == NULL) 4676 return SSH_ERR_INVALID_ARGUMENT; 4677 if ((k->xmss_filename = strdup(filename)) == NULL) 4678 return SSH_ERR_ALLOC_FAIL; 4679 return 0; 4680 } 4681 #else 4682 int 4683 sshkey_private_serialize_maxsign(struct sshkey *k, struct sshbuf *b, 4684 u_int32_t maxsign, int printerror) 4685 { 4686 return sshkey_private_serialize_opt(k, b, SSHKEY_SERIALIZE_DEFAULT); 4687 } 4688 4689 u_int32_t 4690 sshkey_signatures_left(const struct sshkey *k) 4691 { 4692 return 0; 4693 } 4694 4695 int 4696 sshkey_enable_maxsign(struct sshkey *k, u_int32_t maxsign) 4697 { 4698 return SSH_ERR_INVALID_ARGUMENT; 4699 } 4700 4701 int 4702 sshkey_set_filename(struct sshkey *k, const char *filename) 4703 { 4704 if (k == NULL) 4705 return SSH_ERR_INVALID_ARGUMENT; 4706 return 0; 4707 } 4708 #endif /* WITH_XMSS */ 4709