authfile.c

   1 /* $OpenBSD: authfile.c,v 1.71 2006/07/22 20:48:22 stevesk Exp $ */
   2 /*
   3  * Author: Tatu Ylonen <ylo@cs.hut.fi>
   4  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
   5  *                    All rights reserved
   6  * This file contains functions for reading and writing identity files, and
   7  * for reading the passphrase from the user.
   8  *
   9  * As far as I am concerned, the code I have written for this software
  10  * can be used freely for any purpose.  Any derived versions of this
  11  * software must be clearly marked as such, and if the derived work is
  12  * incompatible with the protocol description in the RFC file, it must be
  13  * called by a name other than "ssh" or "Secure Shell".
  14  *
  15  *
  16  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  17  *
  18  * Redistribution and use in source and binary forms, with or without
  19  * modification, are permitted provided that the following conditions
  20  * are met:
  21  * 1. Redistributions of source code must retain the above copyright
  22  *    notice, this list of conditions and the following disclaimer.
  23  * 2. Redistributions in binary form must reproduce the above copyright
  24  *    notice, this list of conditions and the following disclaimer in the
  25  *    documentation and/or other materials provided with the distribution.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  28  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  29  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  30  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  31  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  32  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  33  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  34  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  35  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  36  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  37  */
  38
  39 #include "includes.h"
  40
  41 #include <sys/types.h>
  42 #include <sys/stat.h>
  43
  44 #include <openssl/err.h>
  45 #include <openssl/evp.h>
  46 #include <openssl/pem.h>
  47
  48 #include <errno.h>
  49 #include <fcntl.h>
  50 #include <string.h>
  51 #include <unistd.h>
  52
  53 #include "cipher.h"
  54 #include "xmalloc.h"
  55 #include "buffer.h"
  56 #include "bufaux.h"
  57 #include "key.h"
  58 #include "ssh.h"
  59 #include "log.h"
  60 #include "authfile.h"
  61 #include "rsa.h"
  62 #include "misc.h"
  63 #include "atomicio.h"
  64
  65 /* Version identification string for SSH v1 identity files. */
  66 static const char authfile_id_string[] =
  67     "SSH PRIVATE KEY FILE FORMAT 1.1\n";
  68
  69 /*
  70  * Saves the authentication (private) key in a file, encrypting it with
  71  * passphrase.  The identification of the file (lowest 64 bits of n) will
  72  * precede the key to provide identification of the key without needing a
  73  * passphrase.
  74  */
  75
  76 static int
  77 key_save_private_rsa1(Key *key, const char *filename, const char *passphrase,
  78     const char *comment)
  79 {
  80         Buffer buffer, encrypted;
  81         u_char buf[100], *cp;
  82         int fd, i, cipher_num;
  83         CipherContext ciphercontext;
  84         Cipher *cipher;
  85         u_int32_t rnd;
  86
  87         /*
  88          * If the passphrase is empty, use SSH_CIPHER_NONE to ease converting
  89          * to another cipher; otherwise use SSH_AUTHFILE_CIPHER.
  90          */
  91         cipher_num = (strcmp(passphrase, "") == 0) ?
  92             SSH_CIPHER_NONE : SSH_AUTHFILE_CIPHER;
  93         if ((cipher = cipher_by_number(cipher_num)) == NULL)
  94                 fatal("save_private_key_rsa: bad cipher");
  95
  96         /* This buffer is used to built the secret part of the private key. */
  97         buffer_init(&buffer);
  98
  99         /* Put checkbytes for checking passphrase validity. */
 100         rnd = arc4random();
 101         buf[0] = rnd & 0xff;
 102         buf[1] = (rnd >> 8) & 0xff;
 103         buf[2] = buf[0];
 104         buf[3] = buf[1];
 105         buffer_append(&buffer, buf, 4);
 106
 107         /*
 108          * Store the private key (n and e will not be stored because they
 109          * will be stored in plain text, and storing them also in encrypted
 110          * format would just give known plaintext).
 111          */
 112         buffer_put_bignum(&buffer, key->rsa->d);
 113         buffer_put_bignum(&buffer, key->rsa->iqmp);
 114         buffer_put_bignum(&buffer, key->rsa->q);        /* reverse from SSL p */
 115         buffer_put_bignum(&buffer, key->rsa->p);        /* reverse from SSL q */
 116
 117         /* Pad the part to be encrypted until its size is a multiple of 8. */
 118         while (buffer_len(&buffer) % 8 != 0)
 119                 buffer_put_char(&buffer, 0);
 120
 121         /* This buffer will be used to contain the data in the file. */
 122         buffer_init(&encrypted);
 123
 124         /* First store keyfile id string. */
 125         for (i = 0; authfile_id_string[i]; i++)
 126                 buffer_put_char(&encrypted, authfile_id_string[i]);
 127         buffer_put_char(&encrypted, 0);
 128
 129         /* Store cipher type. */
 130         buffer_put_char(&encrypted, cipher_num);
 131         buffer_put_int(&encrypted, 0);  /* For future extension */
 132
 133         /* Store public key.  This will be in plain text. */
 134         buffer_put_int(&encrypted, BN_num_bits(key->rsa->n));
 135         buffer_put_bignum(&encrypted, key->rsa->n);
 136         buffer_put_bignum(&encrypted, key->rsa->e);
 137         buffer_put_cstring(&encrypted, comment);
 138
 139         /* Allocate space for the private part of the key in the buffer. */
 140         cp = buffer_append_space(&encrypted, buffer_len(&buffer));
 141
 142         cipher_set_key_string(&ciphercontext, cipher, passphrase,
 143             CIPHER_ENCRYPT);
 144         cipher_crypt(&ciphercontext, cp,
 145             buffer_ptr(&buffer), buffer_len(&buffer));
 146         cipher_cleanup(&ciphercontext);
 147         memset(&ciphercontext, 0, sizeof(ciphercontext));
 148
 149         /* Destroy temporary data. */
 150         memset(buf, 0, sizeof(buf));
 151         buffer_free(&buffer);
 152
 153         fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600);
 154         if (fd < 0) {
 155                 error("open %s failed: %s.", filename, strerror(errno));
 156                 buffer_free(&encrypted);
 157                 return 0;
 158         }
 159         if (atomicio(vwrite, fd, buffer_ptr(&encrypted),
 160             buffer_len(&encrypted)) != buffer_len(&encrypted)) {
 161                 error("write to key file %s failed: %s", filename,
 162                     strerror(errno));
 163                 buffer_free(&encrypted);
 164                 close(fd);
 165                 unlink(filename);
 166                 return 0;
 167         }
 168         close(fd);
 169         buffer_free(&encrypted);
 170         return 1;
 171 }
 172
 173 /* save SSH v2 key in OpenSSL PEM format */
 174 static int
 175 key_save_private_pem(Key *key, const char *filename, const char *_passphrase,
 176     const char *comment)
 177 {
 178         FILE *fp;
 179         int fd;
 180         int success = 0;
 181         int len = strlen(_passphrase);
 182         u_char *passphrase = (len > 0) ? (u_char *)_passphrase : NULL;
 183         const EVP_CIPHER *cipher = (len > 0) ? EVP_des_ede3_cbc() : NULL;
 184
 185         if (len > 0 && len <= 4) {
 186                 error("passphrase too short: have %d bytes, need > 4", len);
 187                 return 0;
 188         }
 189         fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600);
 190         if (fd < 0) {
 191                 error("open %s failed: %s.", filename, strerror(errno));
 192                 return 0;
 193         }
 194         fp = fdopen(fd, "w");
 195         if (fp == NULL ) {
 196                 error("fdopen %s failed: %s.", filename, strerror(errno));
 197                 close(fd);
 198                 return 0;
 199         }
 200         switch (key->type) {
 201         case KEY_DSA:
 202                 success = PEM_write_DSAPrivateKey(fp, key->dsa,
 203                     cipher, passphrase, len, NULL, NULL);
 204                 break;
 205         case KEY_RSA:
 206                 success = PEM_write_RSAPrivateKey(fp, key->rsa,
 207                     cipher, passphrase, len, NULL, NULL);
 208                 break;
 209         }
 210         fclose(fp);
 211         return success;
 212 }
 213
 214 int
 215 key_save_private(Key *key, const char *filename, const char *passphrase,
 216     const char *comment)
 217 {
 218         switch (key->type) {
 219         case KEY_RSA1:
 220                 return key_save_private_rsa1(key, filename, passphrase,
 221                     comment);
 222         case KEY_DSA:
 223         case KEY_RSA:
 224                 return key_save_private_pem(key, filename, passphrase,
 225                     comment);
 226         default:
 227                 break;
 228         }
 229         error("key_save_private: cannot save key type %d", key->type);
 230         return 0;
 231 }
 232
 233 /*
 234  * Loads the public part of the ssh v1 key file.  Returns NULL if an error was
 235  * encountered (the file does not exist or is not readable), and the key
 236  * otherwise.
 237  */
 238
 239 static Key *
 240 key_load_public_rsa1(int fd, const char *filename, char **commentp)
 241 {
 242         Buffer buffer;
 243         Key *pub;
 244         struct stat st;
 245         char *cp;
 246         u_int i;
 247         size_t len;
 248
 249         if (fstat(fd, &st) < 0) {
 250                 error("fstat for key file %.200s failed: %.100s",
 251                     filename, strerror(errno));
 252                 return NULL;
 253         }
 254         if (st.st_size > 1*1024*1024) {
 255                 error("key file %.200s too large", filename);
 256                 return NULL;
 257         }
 258         len = (size_t)st.st_size;               /* truncated */
 259
 260         buffer_init(&buffer);
 261         cp = buffer_append_space(&buffer, len);
 262
 263         if (atomicio(read, fd, cp, len) != len) {
 264                 debug("Read from key file %.200s failed: %.100s", filename,
 265                     strerror(errno));
 266                 buffer_free(&buffer);
 267                 return NULL;
 268         }
 269
 270         /* Check that it is at least big enough to contain the ID string. */
 271         if (len < sizeof(authfile_id_string)) {
 272                 debug3("Not a RSA1 key file %.200s.", filename);
 273                 buffer_free(&buffer);
 274                 return NULL;
 275         }
 276         /*
 277          * Make sure it begins with the id string.  Consume the id string
 278          * from the buffer.
 279          */
 280         for (i = 0; i < sizeof(authfile_id_string); i++)
 281                 if (buffer_get_char(&buffer) != authfile_id_string[i]) {
 282                         debug3("Not a RSA1 key file %.200s.", filename);
 283                         buffer_free(&buffer);
 284                         return NULL;
 285                 }
 286         /* Skip cipher type and reserved data. */
 287         (void) buffer_get_char(&buffer);        /* cipher type */
 288         (void) buffer_get_int(&buffer);         /* reserved */
 289
 290         /* Read the public key from the buffer. */
 291         (void) buffer_get_int(&buffer);
 292         pub = key_new(KEY_RSA1);
 293         buffer_get_bignum(&buffer, pub->rsa->n);
 294         buffer_get_bignum(&buffer, pub->rsa->e);
 295         if (commentp)
 296                 *commentp = buffer_get_string(&buffer, NULL);
 297         /* The encrypted private part is not parsed by this function. */
 298
 299         buffer_free(&buffer);
 300         return pub;
 301 }
 302
 303 /* load public key from private-key file, works only for SSH v1 */
 304 Key *
 305 key_load_public_type(int type, const char *filename, char **commentp)
 306 {
 307         Key *pub;
 308         int fd;
 309
 310         if (type == KEY_RSA1) {
 311                 fd = open(filename, O_RDONLY);
 312                 if (fd < 0)
 313                         return NULL;
 314                 pub = key_load_public_rsa1(fd, filename, commentp);
 315                 close(fd);
 316                 return pub;
 317         }
 318         return NULL;
 319 }
 320
 321 /*
 322  * Loads the private key from the file.  Returns 0 if an error is encountered
 323  * (file does not exist or is not readable, or passphrase is bad). This
 324  * initializes the private key.
 325  * Assumes we are called under uid of the owner of the file.
 326  */
 327
 328 static Key *
 329 key_load_private_rsa1(int fd, const char *filename, const char *passphrase,
 330     char **commentp)
 331 {
 332         u_int i;
 333         int check1, check2, cipher_type;
 334         size_t len;
 335         Buffer buffer, decrypted;
 336         u_char *cp;
 337         CipherContext ciphercontext;
 338         Cipher *cipher;
 339         Key *prv = NULL;
 340         struct stat st;
 341
 342         if (fstat(fd, &st) < 0) {
 343                 error("fstat for key file %.200s failed: %.100s",
 344                     filename, strerror(errno));
 345                 close(fd);
 346                 return NULL;
 347         }
 348         if (st.st_size > 1*1024*1024) {
 349                 error("key file %.200s too large", filename);
 350                 close(fd);
 351                 return (NULL);
 352         }
 353         len = (size_t)st.st_size;               /* truncated */
 354
 355         buffer_init(&buffer);
 356         cp = buffer_append_space(&buffer, len);
 357
 358         if (atomicio(read, fd, cp, len) != len) {
 359                 debug("Read from key file %.200s failed: %.100s", filename,
 360                     strerror(errno));
 361                 buffer_free(&buffer);
 362                 close(fd);
 363                 return NULL;
 364         }
 365
 366         /* Check that it is at least big enough to contain the ID string. */
 367         if (len < sizeof(authfile_id_string)) {
 368                 debug3("Not a RSA1 key file %.200s.", filename);
 369                 buffer_free(&buffer);
 370                 close(fd);
 371                 return NULL;
 372         }
 373         /*
 374          * Make sure it begins with the id string.  Consume the id string
 375          * from the buffer.
 376          */
 377         for (i = 0; i < sizeof(authfile_id_string); i++)
 378                 if (buffer_get_char(&buffer) != authfile_id_string[i]) {
 379                         debug3("Not a RSA1 key file %.200s.", filename);
 380                         buffer_free(&buffer);
 381                         close(fd);
 382                         return NULL;
 383                 }
 384
 385         /* Read cipher type. */
 386         cipher_type = buffer_get_char(&buffer);
 387         (void) buffer_get_int(&buffer); /* Reserved data. */
 388
 389         /* Read the public key from the buffer. */
 390         (void) buffer_get_int(&buffer);
 391         prv = key_new_private(KEY_RSA1);
 392
 393         buffer_get_bignum(&buffer, prv->rsa->n);
 394         buffer_get_bignum(&buffer, prv->rsa->e);
 395         if (commentp)
 396                 *commentp = buffer_get_string(&buffer, NULL);
 397         else
 398                 xfree(buffer_get_string(&buffer, NULL));
 399
 400         /* Check that it is a supported cipher. */
 401         cipher = cipher_by_number(cipher_type);
 402         if (cipher == NULL) {
 403                 debug("Unsupported cipher %d used in key file %.200s.",
 404                     cipher_type, filename);
 405                 buffer_free(&buffer);
 406                 goto fail;
 407         }
 408         /* Initialize space for decrypted data. */
 409         buffer_init(&decrypted);
 410         cp = buffer_append_space(&decrypted, buffer_len(&buffer));
 411
 412         /* Rest of the buffer is encrypted.  Decrypt it using the passphrase. */
 413         cipher_set_key_string(&ciphercontext, cipher, passphrase,
 414             CIPHER_DECRYPT);
 415         cipher_crypt(&ciphercontext, cp,
 416             buffer_ptr(&buffer), buffer_len(&buffer));
 417         cipher_cleanup(&ciphercontext);
 418         memset(&ciphercontext, 0, sizeof(ciphercontext));
 419         buffer_free(&buffer);
 420
 421         check1 = buffer_get_char(&decrypted);
 422         check2 = buffer_get_char(&decrypted);
 423         if (check1 != buffer_get_char(&decrypted) ||
 424             check2 != buffer_get_char(&decrypted)) {
 425                 if (strcmp(passphrase, "") != 0)
 426                         debug("Bad passphrase supplied for key file %.200s.",
 427                             filename);
 428                 /* Bad passphrase. */
 429                 buffer_free(&decrypted);
 430                 goto fail;
 431         }
 432         /* Read the rest of the private key. */
 433         buffer_get_bignum(&decrypted, prv->rsa->d);
 434         buffer_get_bignum(&decrypted, prv->rsa->iqmp);          /* u */
 435         /* in SSL and SSH v1 p and q are exchanged */
 436         buffer_get_bignum(&decrypted, prv->rsa->q);             /* p */
 437         buffer_get_bignum(&decrypted, prv->rsa->p);             /* q */
 438
 439         /* calculate p-1 and q-1 */
 440         rsa_generate_additional_parameters(prv->rsa);
 441
 442         buffer_free(&decrypted);
 443
 444         /* enable blinding */
 445         if (RSA_blinding_on(prv->rsa, NULL) != 1) {
 446                 error("key_load_private_rsa1: RSA_blinding_on failed");
 447                 goto fail;
 448         }
 449         close(fd);
 450         return prv;
 451
 452 fail:
 453         if (commentp)
 454                 xfree(*commentp);
 455         close(fd);
 456         key_free(prv);
 457         return NULL;
 458 }
 459
 460 Key *
 461 key_load_private_pem(int fd, int type, const char *passphrase,
 462     char **commentp)
 463 {
 464         FILE *fp;
 465         EVP_PKEY *pk = NULL;
 466         Key *prv = NULL;
 467         char *name = "<no key>";
 468
 469         fp = fdopen(fd, "r");
 470         if (fp == NULL) {
 471                 error("fdopen failed: %s", strerror(errno));
 472                 close(fd);
 473                 return NULL;
 474         }
 475         pk = PEM_read_PrivateKey(fp, NULL, NULL, (char *)passphrase);
 476         if (pk == NULL) {
 477                 debug("PEM_read_PrivateKey failed");
 478                 (void)ERR_get_error();
 479         } else if (pk->type == EVP_PKEY_RSA &&
 480             (type == KEY_UNSPEC||type==KEY_RSA)) {
 481                 prv = key_new(KEY_UNSPEC);
 482                 prv->rsa = EVP_PKEY_get1_RSA(pk);
 483                 prv->type = KEY_RSA;
 484                 name = "rsa w/o comment";
 485 #ifdef DEBUG_PK
 486                 RSA_print_fp(stderr, prv->rsa, 8);
 487 #endif
 488                 if (RSA_blinding_on(prv->rsa, NULL) != 1) {
 489                         error("key_load_private_pem: RSA_blinding_on failed");
 490                         key_free(prv);
 491                         prv = NULL;
 492                 }
 493         } else if (pk->type == EVP_PKEY_DSA &&
 494             (type == KEY_UNSPEC||type==KEY_DSA)) {
 495                 prv = key_new(KEY_UNSPEC);
 496                 prv->dsa = EVP_PKEY_get1_DSA(pk);
 497                 prv->type = KEY_DSA;
 498                 name = "dsa w/o comment";
 499 #ifdef DEBUG_PK
 500                 DSA_print_fp(stderr, prv->dsa, 8);
 501 #endif
 502         } else {
 503                 error("PEM_read_PrivateKey: mismatch or "
 504                     "unknown EVP_PKEY save_type %d", pk->save_type);
 505         }
 506         fclose(fp);
 507         if (pk != NULL)
 508                 EVP_PKEY_free(pk);
 509         if (prv != NULL && commentp)
 510                 *commentp = xstrdup(name);
 511         debug("read PEM private key done: type %s",
 512             prv ? key_type(prv) : "<unknown>");
 513         return prv;
 514 }
 515
 516 int
 517 key_perm_ok(int fd, const char *filename)
 518 {
 519         struct stat st;
 520
 521         if (fstat(fd, &st) < 0)
 522                 return 0;
 523         /*
 524          * if a key owned by the user is accessed, then we check the
 525          * permissions of the file. if the key owned by a different user,
 526          * then we don't care.
 527          */
 528 #ifdef HAVE_CYGWIN
 529         if (check_ntsec(filename))
 530 #endif
 531         if ((st.st_uid == getuid()) && (st.st_mode & 077) != 0) {
 532                 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
 533                 error("@         WARNING: UNPROTECTED PRIVATE KEY FILE!          @");
 534                 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
 535                 error("Permissions 0%3.3o for '%s' are too open.",
 536                     (u_int)st.st_mode & 0777, filename);
 537                 error("It is recommended that your private key files are NOT accessible by others.");
 538                 error("This private key will be ignored.");
 539                 return 0;
 540         }
 541         return 1;
 542 }
 543
 544 Key *
 545 key_load_private_type(int type, const char *filename, const char *passphrase,
 546     char **commentp, int *perm_ok)
 547 {
 548         int fd;
 549
 550         fd = open(filename, O_RDONLY);
 551         if (fd < 0)
 552                 return NULL;
 553         if (!key_perm_ok(fd, filename)) {
 554                 if (perm_ok != NULL)
 555                         *perm_ok = 0;
 556                 error("bad permissions: ignore key: %s", filename);
 557                 close(fd);
 558                 return NULL;
 559         }
 560         if (perm_ok != NULL)
 561                 *perm_ok = 1;
 562         switch (type) {
 563         case KEY_RSA1:
 564                 return key_load_private_rsa1(fd, filename, passphrase,
 565                     commentp);
 566                 /* closes fd */
 567         case KEY_DSA:
 568         case KEY_RSA:
 569         case KEY_UNSPEC:
 570                 return key_load_private_pem(fd, type, passphrase, commentp);
 571                 /* closes fd */
 572         default:
 573                 close(fd);
 574                 break;
 575         }
 576         return NULL;
 577 }
 578
 579 Key *
 580 key_load_private(const char *filename, const char *passphrase,
 581     char **commentp)
 582 {
 583         Key *pub, *prv;
 584         int fd;
 585
 586         fd = open(filename, O_RDONLY);
 587         if (fd < 0)
 588                 return NULL;
 589         if (!key_perm_ok(fd, filename)) {
 590                 error("bad permissions: ignore key: %s", filename);
 591                 close(fd);
 592                 return NULL;
 593         }
 594         pub = key_load_public_rsa1(fd, filename, commentp);
 595         lseek(fd, (off_t) 0, SEEK_SET);         /* rewind */
 596         if (pub == NULL) {
 597                 /* closes fd */
 598                 prv = key_load_private_pem(fd, KEY_UNSPEC, passphrase, NULL);
 599                 /* use the filename as a comment for PEM */
 600                 if (commentp && prv)
 601                         *commentp = xstrdup(filename);
 602         } else {
 603                 /* it's a SSH v1 key if the public key part is readable */
 604                 key_free(pub);
 605                 /* closes fd */
 606                 prv = key_load_private_rsa1(fd, filename, passphrase, NULL);
 607         }
 608         return prv;
 609 }
 610
 611 static int
 612 key_try_load_public(Key *k, const char *filename, char **commentp)
 613 {
 614         FILE *f;
 615         char line[SSH_MAX_PUBKEY_BYTES];
 616         char *cp;
 617         u_long linenum = 0;
 618
 619         f = fopen(filename, "r");
 620         if (f != NULL) {
 621                 while (read_keyfile_line(f, filename, line, sizeof(line),
 622                             &linenum) != -1) {
 623                         cp = line;
 624                         switch (*cp) {
 625                         case '#':
 626                         case '\n':
 627                         case '\0':
 628                                 continue;
 629                         }
 630                         /* Skip leading whitespace. */
 631                         for (; *cp && (*cp == ' ' || *cp == '\t'); cp++)
 632                                 ;
 633                         if (*cp) {
 634                                 if (key_read(k, &cp) == 1) {
 635                                         if (commentp)
 636                                                 *commentp=xstrdup(filename);
 637                                         fclose(f);
 638                                         return 1;
 639                                 }
 640                         }
 641                 }
 642                 fclose(f);
 643         }
 644         return 0;
 645 }
 646
 647 /* load public key from ssh v1 private or any pubkey file */
 648 Key *
 649 key_load_public(const char *filename, char **commentp)
 650 {
 651         Key *pub;
 652         char file[MAXPATHLEN];
 653
 654         /* try rsa1 private key */
 655         pub = key_load_public_type(KEY_RSA1, filename, commentp);
 656         if (pub != NULL)
 657                 return pub;
 658
 659         /* try rsa1 public key */
 660         pub = key_new(KEY_RSA1);
 661         if (key_try_load_public(pub, filename, commentp) == 1)
 662                 return pub;
 663         key_free(pub);
 664
 665         /* try ssh2 public key */
 666         pub = key_new(KEY_UNSPEC);
 667         if (key_try_load_public(pub, filename, commentp) == 1)
 668                 return pub;
 669         if ((strlcpy(file, filename, sizeof file) < sizeof(file)) &&
 670             (strlcat(file, ".pub", sizeof file) < sizeof(file)) &&
 671             (key_try_load_public(pub, file, commentp) == 1))
 672                 return pub;
 673         key_free(pub);
 674         return NULL;
 675 }