1 /* $NetBSD: authfile.c,v 1.3 2010/11/21 18:29:48 adam Exp $ */ 2 /* $OpenBSD: authfile.c,v 1.82 2010/08/04 05:49:22 djm Exp $ */ 3 /* 4 * Author: Tatu Ylonen <ylo@cs.hut.fi> 5 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 6 * All rights reserved 7 * This file contains functions for reading and writing identity files, and 8 * for reading the passphrase from the user. 9 * 10 * As far as I am concerned, the code I have written for this software 11 * can be used freely for any purpose. Any derived versions of this 12 * software must be clearly marked as such, and if the derived work is 13 * incompatible with the protocol description in the RFC file, it must be 14 * called by a name other than "ssh" or "Secure Shell". 15 * 16 * 17 * Copyright (c) 2000 Markus Friedl. All rights reserved. 18 * 19 * Redistribution and use in source and binary forms, with or without 20 * modification, are permitted provided that the following conditions 21 * are met: 22 * 1. Redistributions of source code must retain the above copyright 23 * notice, this list of conditions and the following disclaimer. 24 * 2. Redistributions in binary form must reproduce the above copyright 25 * notice, this list of conditions and the following disclaimer in the 26 * documentation and/or other materials provided with the distribution. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 29 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 30 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 31 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 32 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 33 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 37 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40 #include "includes.h" 41 __RCSID("$NetBSD: authfile.c,v 1.3 2010/11/21 18:29:48 adam Exp $"); 42 #include <sys/types.h> 43 #include <sys/stat.h> 44 #include <sys/param.h> 45 #include <sys/uio.h> 46 47 #include <openssl/err.h> 48 #include <openssl/evp.h> 49 #include <openssl/pem.h> 50 51 #include <errno.h> 52 #include <fcntl.h> 53 #include <stdio.h> 54 #include <stdlib.h> 55 #include <string.h> 56 #include <unistd.h> 57 58 #include "xmalloc.h" 59 #include "cipher.h" 60 #include "buffer.h" 61 #include "key.h" 62 #include "ssh.h" 63 #include "log.h" 64 #include "authfile.h" 65 #include "rsa.h" 66 #include "misc.h" 67 #include "atomicio.h" 68 69 /* Version identification string for SSH v1 identity files. */ 70 static const char authfile_id_string[] = 71 "SSH PRIVATE KEY FILE FORMAT 1.1\n"; 72 73 /* 74 * Saves the authentication (private) key in a file, encrypting it with 75 * passphrase. The identification of the file (lowest 64 bits of n) will 76 * precede the key to provide identification of the key without needing a 77 * passphrase. 78 */ 79 80 static int 81 key_save_private_rsa1(Key *key, const char *filename, const char *passphrase, 82 const char *comment) 83 { 84 Buffer buffer, encrypted; 85 u_char buf[100], *cp; 86 int fd, i, cipher_num; 87 CipherContext ciphercontext; 88 Cipher *cipher; 89 u_int32_t rnd; 90 91 /* 92 * If the passphrase is empty, use SSH_CIPHER_NONE to ease converting 93 * to another cipher; otherwise use SSH_AUTHFILE_CIPHER. 94 */ 95 cipher_num = (strcmp(passphrase, "") == 0) ? 96 SSH_CIPHER_NONE : SSH_AUTHFILE_CIPHER; 97 if ((cipher = cipher_by_number(cipher_num)) == NULL) 98 fatal("save_private_key_rsa: bad cipher"); 99 100 /* This buffer is used to built the secret part of the private key. */ 101 buffer_init(&buffer); 102 103 /* Put checkbytes for checking passphrase validity. */ 104 rnd = arc4random(); 105 buf[0] = rnd & 0xff; 106 buf[1] = (rnd >> 8) & 0xff; 107 buf[2] = buf[0]; 108 buf[3] = buf[1]; 109 buffer_append(&buffer, buf, 4); 110 111 /* 112 * Store the private key (n and e will not be stored because they 113 * will be stored in plain text, and storing them also in encrypted 114 * format would just give known plaintext). 115 */ 116 buffer_put_bignum(&buffer, key->rsa->d); 117 buffer_put_bignum(&buffer, key->rsa->iqmp); 118 buffer_put_bignum(&buffer, key->rsa->q); /* reverse from SSL p */ 119 buffer_put_bignum(&buffer, key->rsa->p); /* reverse from SSL q */ 120 121 /* Pad the part to be encrypted until its size is a multiple of 8. */ 122 while (buffer_len(&buffer) % 8 != 0) 123 buffer_put_char(&buffer, 0); 124 125 /* This buffer will be used to contain the data in the file. */ 126 buffer_init(&encrypted); 127 128 /* First store keyfile id string. */ 129 for (i = 0; authfile_id_string[i]; i++) 130 buffer_put_char(&encrypted, authfile_id_string[i]); 131 buffer_put_char(&encrypted, 0); 132 133 /* Store cipher type. */ 134 buffer_put_char(&encrypted, cipher_num); 135 buffer_put_int(&encrypted, 0); /* For future extension */ 136 137 /* Store public key. This will be in plain text. */ 138 buffer_put_int(&encrypted, BN_num_bits(key->rsa->n)); 139 buffer_put_bignum(&encrypted, key->rsa->n); 140 buffer_put_bignum(&encrypted, key->rsa->e); 141 buffer_put_cstring(&encrypted, comment); 142 143 /* Allocate space for the private part of the key in the buffer. */ 144 cp = buffer_append_space(&encrypted, buffer_len(&buffer)); 145 146 cipher_set_key_string(&ciphercontext, cipher, passphrase, 147 CIPHER_ENCRYPT); 148 cipher_crypt(&ciphercontext, cp, 149 buffer_ptr(&buffer), buffer_len(&buffer)); 150 cipher_cleanup(&ciphercontext); 151 memset(&ciphercontext, 0, sizeof(ciphercontext)); 152 153 /* Destroy temporary data. */ 154 memset(buf, 0, sizeof(buf)); 155 buffer_free(&buffer); 156 157 fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600); 158 if (fd < 0) { 159 error("open %s failed: %s.", filename, strerror(errno)); 160 buffer_free(&encrypted); 161 return 0; 162 } 163 if (atomicio(vwrite, fd, buffer_ptr(&encrypted), 164 buffer_len(&encrypted)) != buffer_len(&encrypted)) { 165 error("write to key file %s failed: %s", filename, 166 strerror(errno)); 167 buffer_free(&encrypted); 168 close(fd); 169 unlink(filename); 170 return 0; 171 } 172 close(fd); 173 buffer_free(&encrypted); 174 return 1; 175 } 176 177 /* save SSH v2 key in OpenSSL PEM format */ 178 static int 179 key_save_private_pem(Key *key, const char *filename, const char *_passphrase, 180 const char *comment) 181 { 182 FILE *fp; 183 int fd; 184 int success = 0; 185 int len = strlen(_passphrase); 186 u_char *passphrase = (len > 0) ? (u_char *)_passphrase : NULL; 187 const EVP_CIPHER *cipher = (len > 0) ? EVP_aes_128_cbc() : NULL; 188 189 if (len > 0 && len <= 4) { 190 error("passphrase too short: have %d bytes, need > 4", len); 191 return 0; 192 } 193 fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600); 194 if (fd < 0) { 195 error("open %s failed: %s.", filename, strerror(errno)); 196 return 0; 197 } 198 fp = fdopen(fd, "w"); 199 if (fp == NULL) { 200 error("fdopen %s failed: %s.", filename, strerror(errno)); 201 close(fd); 202 return 0; 203 } 204 switch (key->type) { 205 case KEY_DSA: 206 success = PEM_write_DSAPrivateKey(fp, key->dsa, 207 cipher, passphrase, len, NULL, NULL); 208 break; 209 case KEY_RSA: 210 success = PEM_write_RSAPrivateKey(fp, key->rsa, 211 cipher, passphrase, len, NULL, NULL); 212 break; 213 } 214 fclose(fp); 215 return success; 216 } 217 218 int 219 key_save_private(Key *key, const char *filename, const char *passphrase, 220 const char *comment) 221 { 222 switch (key->type) { 223 case KEY_RSA1: 224 return key_save_private_rsa1(key, filename, passphrase, 225 comment); 226 case KEY_DSA: 227 case KEY_RSA: 228 return key_save_private_pem(key, filename, passphrase, 229 comment); 230 default: 231 break; 232 } 233 error("key_save_private: cannot save key type %d", key->type); 234 return 0; 235 } 236 237 /* 238 * Loads the public part of the ssh v1 key file. Returns NULL if an error was 239 * encountered (the file does not exist or is not readable), and the key 240 * otherwise. 241 */ 242 243 static Key * 244 key_load_public_rsa1(int fd, const char *filename, char **commentp) 245 { 246 Buffer buffer; 247 Key *pub; 248 struct stat st; 249 char *cp; 250 u_int i; 251 size_t len; 252 253 if (fstat(fd, &st) < 0) { 254 error("fstat for key file %.200s failed: %.100s", 255 filename, strerror(errno)); 256 return NULL; 257 } 258 if (st.st_size > 1*1024*1024) { 259 error("key file %.200s too large", filename); 260 return NULL; 261 } 262 len = (size_t)st.st_size; /* truncated */ 263 264 buffer_init(&buffer); 265 cp = buffer_append_space(&buffer, len); 266 267 if (atomicio(read, fd, cp, len) != len) { 268 debug("Read from key file %.200s failed: %.100s", filename, 269 strerror(errno)); 270 buffer_free(&buffer); 271 return NULL; 272 } 273 274 /* Check that it is at least big enough to contain the ID string. */ 275 if (len < sizeof(authfile_id_string)) { 276 debug3("Not a RSA1 key file %.200s.", filename); 277 buffer_free(&buffer); 278 return NULL; 279 } 280 /* 281 * Make sure it begins with the id string. Consume the id string 282 * from the buffer. 283 */ 284 for (i = 0; i < sizeof(authfile_id_string); i++) 285 if (buffer_get_char(&buffer) != authfile_id_string[i]) { 286 debug3("Not a RSA1 key file %.200s.", filename); 287 buffer_free(&buffer); 288 return NULL; 289 } 290 /* Skip cipher type and reserved data. */ 291 (void) buffer_get_char(&buffer); /* cipher type */ 292 (void) buffer_get_int(&buffer); /* reserved */ 293 294 /* Read the public key from the buffer. */ 295 (void) buffer_get_int(&buffer); 296 pub = key_new(KEY_RSA1); 297 buffer_get_bignum(&buffer, pub->rsa->n); 298 buffer_get_bignum(&buffer, pub->rsa->e); 299 if (commentp) 300 *commentp = buffer_get_string(&buffer, NULL); 301 /* The encrypted private part is not parsed by this function. */ 302 303 buffer_free(&buffer); 304 return pub; 305 } 306 307 /* load public key from private-key file, works only for SSH v1 */ 308 Key * 309 key_load_public_type(int type, const char *filename, char **commentp) 310 { 311 Key *pub; 312 int fd; 313 314 if (type == KEY_RSA1) { 315 fd = open(filename, O_RDONLY); 316 if (fd < 0) 317 return NULL; 318 pub = key_load_public_rsa1(fd, filename, commentp); 319 close(fd); 320 return pub; 321 } 322 return NULL; 323 } 324 325 /* 326 * Loads the private key from the file. Returns 0 if an error is encountered 327 * (file does not exist or is not readable, or passphrase is bad). This 328 * initializes the private key. 329 * Assumes we are called under uid of the owner of the file. 330 */ 331 332 static Key * 333 key_load_private_rsa1(int fd, const char *filename, const char *passphrase, 334 char **commentp) 335 { 336 u_int i; 337 int check1, check2, cipher_type; 338 size_t len; 339 Buffer buffer, decrypted; 340 u_char *cp; 341 CipherContext ciphercontext; 342 Cipher *cipher; 343 Key *prv = NULL; 344 struct stat st; 345 346 if (fstat(fd, &st) < 0) { 347 error("fstat for key file %.200s failed: %.100s", 348 filename, strerror(errno)); 349 close(fd); 350 return NULL; 351 } 352 if (st.st_size > 1*1024*1024) { 353 error("key file %.200s too large", filename); 354 close(fd); 355 return (NULL); 356 } 357 len = (size_t)st.st_size; /* truncated */ 358 359 buffer_init(&buffer); 360 cp = buffer_append_space(&buffer, len); 361 362 if (atomicio(read, fd, cp, len) != len) { 363 debug("Read from key file %.200s failed: %.100s", filename, 364 strerror(errno)); 365 buffer_free(&buffer); 366 close(fd); 367 return NULL; 368 } 369 370 /* Check that it is at least big enough to contain the ID string. */ 371 if (len < sizeof(authfile_id_string)) { 372 debug3("Not a RSA1 key file %.200s.", filename); 373 buffer_free(&buffer); 374 close(fd); 375 return NULL; 376 } 377 /* 378 * Make sure it begins with the id string. Consume the id string 379 * from the buffer. 380 */ 381 for (i = 0; i < sizeof(authfile_id_string); i++) 382 if (buffer_get_char(&buffer) != authfile_id_string[i]) { 383 debug3("Not a RSA1 key file %.200s.", filename); 384 buffer_free(&buffer); 385 close(fd); 386 return NULL; 387 } 388 389 /* Read cipher type. */ 390 cipher_type = buffer_get_char(&buffer); 391 (void) buffer_get_int(&buffer); /* Reserved data. */ 392 393 /* Read the public key from the buffer. */ 394 (void) buffer_get_int(&buffer); 395 prv = key_new_private(KEY_RSA1); 396 397 buffer_get_bignum(&buffer, prv->rsa->n); 398 buffer_get_bignum(&buffer, prv->rsa->e); 399 if (commentp) 400 *commentp = buffer_get_string(&buffer, NULL); 401 else 402 xfree(buffer_get_string(&buffer, NULL)); 403 404 /* Check that it is a supported cipher. */ 405 cipher = cipher_by_number(cipher_type); 406 if (cipher == NULL) { 407 debug("Unsupported cipher %d used in key file %.200s.", 408 cipher_type, filename); 409 buffer_free(&buffer); 410 goto fail; 411 } 412 /* Initialize space for decrypted data. */ 413 buffer_init(&decrypted); 414 cp = buffer_append_space(&decrypted, buffer_len(&buffer)); 415 416 /* Rest of the buffer is encrypted. Decrypt it using the passphrase. */ 417 cipher_set_key_string(&ciphercontext, cipher, passphrase, 418 CIPHER_DECRYPT); 419 cipher_crypt(&ciphercontext, cp, 420 buffer_ptr(&buffer), buffer_len(&buffer)); 421 cipher_cleanup(&ciphercontext); 422 memset(&ciphercontext, 0, sizeof(ciphercontext)); 423 buffer_free(&buffer); 424 425 check1 = buffer_get_char(&decrypted); 426 check2 = buffer_get_char(&decrypted); 427 if (check1 != buffer_get_char(&decrypted) || 428 check2 != buffer_get_char(&decrypted)) { 429 if (strcmp(passphrase, "") != 0) 430 debug("Bad passphrase supplied for key file %.200s.", 431 filename); 432 /* Bad passphrase. */ 433 buffer_free(&decrypted); 434 goto fail; 435 } 436 /* Read the rest of the private key. */ 437 buffer_get_bignum(&decrypted, prv->rsa->d); 438 buffer_get_bignum(&decrypted, prv->rsa->iqmp); /* u */ 439 /* in SSL and SSH v1 p and q are exchanged */ 440 buffer_get_bignum(&decrypted, prv->rsa->q); /* p */ 441 buffer_get_bignum(&decrypted, prv->rsa->p); /* q */ 442 443 /* calculate p-1 and q-1 */ 444 rsa_generate_additional_parameters(prv->rsa); 445 446 buffer_free(&decrypted); 447 448 /* enable blinding */ 449 if (RSA_blinding_on(prv->rsa, NULL) != 1) { 450 error("key_load_private_rsa1: RSA_blinding_on failed"); 451 goto fail; 452 } 453 close(fd); 454 return prv; 455 456 fail: 457 if (commentp) 458 xfree(*commentp); 459 close(fd); 460 key_free(prv); 461 return NULL; 462 } 463 464 Key * 465 key_load_private_pem(int fd, int type, const char *passphrase, 466 char **commentp) 467 { 468 FILE *fp; 469 EVP_PKEY *pk = NULL; 470 Key *prv = NULL; 471 char *name = "<no key>"; 472 473 fp = fdopen(fd, "r"); 474 if (fp == NULL) { 475 error("fdopen failed: %s", strerror(errno)); 476 close(fd); 477 return NULL; 478 } 479 pk = PEM_read_PrivateKey(fp, NULL, NULL, (char *)passphrase); 480 if (pk == NULL) { 481 debug("PEM_read_PrivateKey failed"); 482 (void)ERR_get_error(); 483 } else if (pk->type == EVP_PKEY_RSA && 484 (type == KEY_UNSPEC||type==KEY_RSA)) { 485 prv = key_new(KEY_UNSPEC); 486 prv->rsa = EVP_PKEY_get1_RSA(pk); 487 prv->type = KEY_RSA; 488 name = "rsa w/o comment"; 489 #ifdef DEBUG_PK 490 RSA_print_fp(stderr, prv->rsa, 8); 491 #endif 492 if (RSA_blinding_on(prv->rsa, NULL) != 1) { 493 error("key_load_private_pem: RSA_blinding_on failed"); 494 key_free(prv); 495 prv = NULL; 496 } 497 } else if (pk->type == EVP_PKEY_DSA && 498 (type == KEY_UNSPEC||type==KEY_DSA)) { 499 prv = key_new(KEY_UNSPEC); 500 prv->dsa = EVP_PKEY_get1_DSA(pk); 501 prv->type = KEY_DSA; 502 name = "dsa w/o comment"; 503 #ifdef DEBUG_PK 504 DSA_print_fp(stderr, prv->dsa, 8); 505 #endif 506 } else { 507 error("PEM_read_PrivateKey: mismatch or " 508 "unknown EVP_PKEY save_type %d", pk->save_type); 509 } 510 fclose(fp); 511 if (pk != NULL) 512 EVP_PKEY_free(pk); 513 if (prv != NULL && commentp) 514 *commentp = xstrdup(name); 515 debug("read PEM private key done: type %s", 516 prv ? key_type(prv) : "<unknown>"); 517 return prv; 518 } 519 520 int 521 key_perm_ok(int fd, const char *filename) 522 { 523 struct stat st; 524 525 if (fstat(fd, &st) < 0) 526 return 0; 527 /* 528 * if a key owned by the user is accessed, then we check the 529 * permissions of the file. if the key owned by a different user, 530 * then we don't care. 531 */ 532 if ((st.st_uid == getuid()) && (st.st_mode & 077) != 0) { 533 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); 534 error("@ WARNING: UNPROTECTED PRIVATE KEY FILE! @"); 535 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); 536 error("Permissions 0%3.3o for '%s' are too open.", 537 (u_int)st.st_mode & 0777, filename); 538 error("It is recommended that your private key files are NOT accessible by others."); 539 error("This private key will be ignored."); 540 return 0; 541 } 542 return 1; 543 } 544 545 Key * 546 key_load_private_type(int type, const char *filename, const char *passphrase, 547 char **commentp, int *perm_ok) 548 { 549 int fd; 550 551 fd = open(filename, O_RDONLY); 552 if (fd < 0) { 553 debug("could not open key file '%s': %s", filename, 554 strerror(errno)); 555 if (perm_ok != NULL) 556 *perm_ok = 0; 557 return NULL; 558 } 559 if (!key_perm_ok(fd, filename)) { 560 if (perm_ok != NULL) 561 *perm_ok = 0; 562 error("bad permissions: ignore key: %s", filename); 563 close(fd); 564 return NULL; 565 } 566 if (perm_ok != NULL) 567 *perm_ok = 1; 568 switch (type) { 569 case KEY_RSA1: 570 return key_load_private_rsa1(fd, filename, passphrase, 571 commentp); 572 /* closes fd */ 573 case KEY_DSA: 574 case KEY_RSA: 575 case KEY_UNSPEC: 576 return key_load_private_pem(fd, type, passphrase, commentp); 577 /* closes fd */ 578 default: 579 close(fd); 580 break; 581 } 582 return NULL; 583 } 584 585 Key * 586 key_load_private(const char *filename, const char *passphrase, 587 char **commentp) 588 { 589 Key *pub, *prv; 590 int fd; 591 592 fd = open(filename, O_RDONLY); 593 if (fd < 0) { 594 debug("could not open key file '%s': %s", filename, 595 strerror(errno)); 596 return NULL; 597 } 598 if (!key_perm_ok(fd, filename)) { 599 error("bad permissions: ignore key: %s", filename); 600 close(fd); 601 return NULL; 602 } 603 pub = key_load_public_rsa1(fd, filename, commentp); 604 lseek(fd, (off_t) 0, SEEK_SET); /* rewind */ 605 if (pub == NULL) { 606 /* closes fd */ 607 prv = key_load_private_pem(fd, KEY_UNSPEC, passphrase, NULL); 608 /* use the filename as a comment for PEM */ 609 if (commentp && prv) 610 *commentp = xstrdup(filename); 611 } else { 612 /* it's a SSH v1 key if the public key part is readable */ 613 key_free(pub); 614 /* closes fd */ 615 prv = key_load_private_rsa1(fd, filename, passphrase, NULL); 616 } 617 return prv; 618 } 619 620 static int 621 key_try_load_public(Key *k, const char *filename, char **commentp) 622 { 623 FILE *f; 624 char line[SSH_MAX_PUBKEY_BYTES]; 625 char *cp; 626 u_long linenum = 0; 627 628 f = fopen(filename, "r"); 629 if (f != NULL) { 630 while (read_keyfile_line(f, filename, line, sizeof(line), 631 &linenum) != -1) { 632 cp = line; 633 switch (*cp) { 634 case '#': 635 case '\n': 636 case '\0': 637 continue; 638 } 639 /* Skip leading whitespace. */ 640 for (; *cp && (*cp == ' ' || *cp == '\t'); cp++) 641 ; 642 if (*cp) { 643 if (key_read(k, &cp) == 1) { 644 if (commentp) 645 *commentp=xstrdup(filename); 646 fclose(f); 647 return 1; 648 } 649 } 650 } 651 fclose(f); 652 } 653 return 0; 654 } 655 656 /* load public key from ssh v1 private or any pubkey file */ 657 Key * 658 key_load_public(const char *filename, char **commentp) 659 { 660 Key *pub; 661 char file[MAXPATHLEN]; 662 663 /* try rsa1 private key */ 664 pub = key_load_public_type(KEY_RSA1, filename, commentp); 665 if (pub != NULL) 666 return pub; 667 668 /* try rsa1 public key */ 669 pub = key_new(KEY_RSA1); 670 if (key_try_load_public(pub, filename, commentp) == 1) 671 return pub; 672 key_free(pub); 673 674 /* try ssh2 public key */ 675 pub = key_new(KEY_UNSPEC); 676 if (key_try_load_public(pub, filename, commentp) == 1) 677 return pub; 678 if ((strlcpy(file, filename, sizeof file) < sizeof(file)) && 679 (strlcat(file, ".pub", sizeof file) < sizeof(file)) && 680 (key_try_load_public(pub, file, commentp) == 1)) 681 return pub; 682 key_free(pub); 683 return NULL; 684 } 685 686 /* Load the certificate associated with the named private key */ 687 Key * 688 key_load_cert(const char *filename) 689 { 690 Key *pub; 691 char *file; 692 693 pub = key_new(KEY_UNSPEC); 694 xasprintf(&file, "%s-cert.pub", filename); 695 if (key_try_load_public(pub, file, NULL) == 1) { 696 xfree(file); 697 return pub; 698 } 699 xfree(file); 700 key_free(pub); 701 return NULL; 702 } 703 704 /* Load private key and certificate */ 705 Key * 706 key_load_private_cert(int type, const char *filename, const char *passphrase, 707 int *perm_ok) 708 { 709 Key *key, *pub; 710 711 switch (type) { 712 case KEY_RSA: 713 case KEY_DSA: 714 break; 715 default: 716 error("%s: unsupported key type", __func__); 717 return NULL; 718 } 719 720 if ((key = key_load_private_type(type, filename, 721 passphrase, NULL, perm_ok)) == NULL) 722 return NULL; 723 724 if ((pub = key_load_cert(filename)) == NULL) { 725 key_free(key); 726 return NULL; 727 } 728 729 /* Make sure the private key matches the certificate */ 730 if (key_equal_public(key, pub) == 0) { 731 error("%s: certificate does not match private key %s", 732 __func__, filename); 733 } else if (key_to_certified(key, key_cert_is_legacy(pub)) != 0) { 734 error("%s: key_to_certified failed", __func__); 735 } else { 736 key_cert_copy(pub, key); 737 key_free(pub); 738 return key; 739 } 740 741 key_free(key); 742 key_free(pub); 743 return NULL; 744 } 745 746 /* 747 * Returns 1 if the specified "key" is listed in the file "filename", 748 * 0 if the key is not listed or -1 on error. 749 * If strict_type is set then the key type must match exactly, 750 * otherwise a comparison that ignores certficiate data is performed. 751 */ 752 int 753 key_in_file(Key *key, const char *filename, int strict_type) 754 { 755 FILE *f; 756 char line[SSH_MAX_PUBKEY_BYTES]; 757 char *cp; 758 u_long linenum = 0; 759 int ret = 0; 760 Key *pub; 761 int (*key_compare)(const Key *, const Key *) = strict_type ? 762 key_equal : key_equal_public; 763 764 if ((f = fopen(filename, "r")) == NULL) { 765 if (errno == ENOENT) { 766 debug("%s: keyfile \"%s\" missing", __func__, filename); 767 return 0; 768 } else { 769 error("%s: could not open keyfile \"%s\": %s", __func__, 770 filename, strerror(errno)); 771 return -1; 772 } 773 } 774 775 while (read_keyfile_line(f, filename, line, sizeof(line), 776 &linenum) != -1) { 777 cp = line; 778 779 /* Skip leading whitespace. */ 780 for (; *cp && (*cp == ' ' || *cp == '\t'); cp++) 781 ; 782 783 /* Skip comments and empty lines */ 784 switch (*cp) { 785 case '#': 786 case '\n': 787 case '\0': 788 continue; 789 } 790 791 pub = key_new(KEY_UNSPEC); 792 if (key_read(pub, &cp) != 1) { 793 key_free(pub); 794 continue; 795 } 796 if (key_compare(key, pub)) { 797 ret = 1; 798 key_free(pub); 799 break; 800 } 801 key_free(pub); 802 } 803 fclose(f); 804 return ret; 805 } 806 807