1 /*- 2 * Copyright (c) 2009 The NetBSD Foundation, Inc. 3 * All rights reserved. 4 * 5 * This code is derived from software contributed to The NetBSD Foundation 6 * by Alistair Crooks (agc@NetBSD.org) 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 18 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 19 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 20 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 21 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 22 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 25 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 27 * POSSIBILITY OF SUCH DAMAGE. 28 */ 29 /* 30 * Copyright (c) 2005-2008 Nominet UK (www.nic.uk) 31 * All rights reserved. 32 * Contributors: Ben Laurie, Rachel Willmer. The Contributors have asserted 33 * their moral rights under the UK Copyright Design and Patents Act 1988 to 34 * be recorded as the authors of this copyright work. 35 * 36 * Licensed under the Apache License, Version 2.0 (the "License"); you may not 37 * use this file except in compliance with the License. 38 * 39 * You may obtain a copy of the License at 40 * http://www.apache.org/licenses/LICENSE-2.0 41 * 42 * Unless required by applicable law or agreed to in writing, software 43 * distributed under the License is distributed on an "AS IS" BASIS, 44 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 45 * 46 * See the License for the specific language governing permissions and 47 * limitations under the License. 48 */ 49 50 /** \file 51 */ 52 #include "config.h" 53 54 #ifdef HAVE_SYS_CDEFS_H 55 #include <sys/cdefs.h> 56 #endif 57 58 #if defined(__NetBSD__) 59 __COPYRIGHT("@(#) Copyright (c) 2009 The NetBSD Foundation, Inc. All rights reserved."); 60 __RCSID("$NetBSD: create.c,v 1.34 2010/09/01 17:25:57 agc Exp $"); 61 #endif 62 63 #include <sys/types.h> 64 #include <sys/param.h> 65 #include <sys/stat.h> 66 67 #ifdef HAVE_FCNTL_H 68 #include <fcntl.h> 69 #endif 70 71 #include <string.h> 72 73 #ifdef HAVE_UNISTD_H 74 #include <unistd.h> 75 #endif 76 77 #ifdef HAVE_OPENSSL_CAST_H 78 #include <openssl/cast.h> 79 #endif 80 81 #include "create.h" 82 #include "keyring.h" 83 #include "packet.h" 84 #include "signature.h" 85 #include "writer.h" 86 #include "readerwriter.h" 87 #include "memory.h" 88 #include "netpgpdefs.h" 89 #include "netpgpdigest.h" 90 91 /** 92 * \ingroup Core_Create 93 * \param length 94 * \param type 95 * \param output 96 * \return 1 if OK, otherwise 0 97 */ 98 99 unsigned 100 __ops_write_ss_header(__ops_output_t *output, 101 unsigned length, 102 __ops_content_enum type) 103 { 104 return __ops_write_length(output, length) && 105 __ops_write_scalar(output, (unsigned)(type - 106 (unsigned)OPS_PTAG_SIG_SUBPKT_BASE), 1); 107 } 108 109 /* 110 * XXX: the general idea of _fast_ is that it doesn't copy stuff the safe 111 * (i.e. non _fast_) version will, and so will also need to be freed. 112 */ 113 114 /** 115 * \ingroup Core_Create 116 * 117 * __ops_fast_create_userid() sets id->userid to the given userid. 118 * This is fast because it is only copying a char*. However, if userid 119 * is changed or freed in the future, this could have injurious results. 120 * \param id 121 * \param userid 122 */ 123 124 void 125 __ops_fast_create_userid(uint8_t **id, uint8_t *userid) 126 { 127 *id = userid; 128 } 129 130 /** 131 * \ingroup Core_WritePackets 132 * \brief Writes a User Id packet 133 * \param id 134 * \param output 135 * \return 1 if OK, otherwise 0 136 */ 137 unsigned 138 __ops_write_struct_userid(__ops_output_t *output, const uint8_t *id) 139 { 140 return __ops_write_ptag(output, OPS_PTAG_CT_USER_ID) && 141 __ops_write_length(output, (unsigned)strlen((const char *) id)) && 142 __ops_write(output, id, (unsigned)strlen((const char *) id)); 143 } 144 145 /** 146 * \ingroup Core_WritePackets 147 * \brief Write a User Id packet. 148 * \param userid 149 * \param output 150 * 151 * \return return value from __ops_write_struct_userid() 152 */ 153 unsigned 154 __ops_write_userid(const uint8_t *userid, __ops_output_t *output) 155 { 156 return __ops_write_struct_userid(output, userid); 157 } 158 159 /** 160 \ingroup Core_MPI 161 */ 162 static unsigned 163 mpi_length(const BIGNUM *bn) 164 { 165 return (unsigned)(2 + (BN_num_bits(bn) + 7) / 8); 166 } 167 168 static unsigned 169 pubkey_length(const __ops_pubkey_t *key) 170 { 171 switch (key->alg) { 172 case OPS_PKA_DSA: 173 return mpi_length(key->key.dsa.p) + mpi_length(key->key.dsa.q) + 174 mpi_length(key->key.dsa.g) + mpi_length(key->key.dsa.y); 175 176 case OPS_PKA_RSA: 177 return mpi_length(key->key.rsa.n) + mpi_length(key->key.rsa.e); 178 179 default: 180 (void) fprintf(stderr, 181 "pubkey_length: unknown key algorithm\n"); 182 } 183 return 0; 184 } 185 186 static unsigned 187 seckey_length(const __ops_seckey_t *key) 188 { 189 int len; 190 191 len = 0; 192 switch (key->pubkey.alg) { 193 case OPS_PKA_DSA: 194 return (unsigned)(mpi_length(key->key.dsa.x) + pubkey_length(&key->pubkey)); 195 case OPS_PKA_RSA: 196 len = mpi_length(key->key.rsa.d) + mpi_length(key->key.rsa.p) + 197 mpi_length(key->key.rsa.q) + mpi_length(key->key.rsa.u); 198 199 return (unsigned)(len + pubkey_length(&key->pubkey)); 200 default: 201 (void) fprintf(stderr, 202 "seckey_length: unknown key algorithm\n"); 203 } 204 return 0; 205 } 206 207 /** 208 * \ingroup Core_Create 209 * \param key 210 * \param t 211 * \param n 212 * \param e 213 */ 214 void 215 __ops_fast_create_rsa_pubkey(__ops_pubkey_t *key, time_t t, 216 BIGNUM *n, BIGNUM *e) 217 { 218 key->version = OPS_V4; 219 key->birthtime = t; 220 key->alg = OPS_PKA_RSA; 221 key->key.rsa.n = n; 222 key->key.rsa.e = e; 223 } 224 225 /* 226 * Note that we support v3 keys here because they're needed for for 227 * verification - the writer doesn't allow them, though 228 */ 229 static unsigned 230 write_pubkey_body(const __ops_pubkey_t *key, __ops_output_t *output) 231 { 232 if (!(__ops_write_scalar(output, (unsigned)key->version, 1) && 233 __ops_write_scalar(output, (unsigned)key->birthtime, 4))) { 234 return 0; 235 } 236 237 if (key->version != 4 && 238 !__ops_write_scalar(output, key->days_valid, 2)) { 239 return 0; 240 } 241 242 if (!__ops_write_scalar(output, (unsigned)key->alg, 1)) { 243 return 0; 244 } 245 246 switch (key->alg) { 247 case OPS_PKA_DSA: 248 return __ops_write_mpi(output, key->key.dsa.p) && 249 __ops_write_mpi(output, key->key.dsa.q) && 250 __ops_write_mpi(output, key->key.dsa.g) && 251 __ops_write_mpi(output, key->key.dsa.y); 252 253 case OPS_PKA_RSA: 254 case OPS_PKA_RSA_ENCRYPT_ONLY: 255 case OPS_PKA_RSA_SIGN_ONLY: 256 return __ops_write_mpi(output, key->key.rsa.n) && 257 __ops_write_mpi(output, key->key.rsa.e); 258 259 case OPS_PKA_ELGAMAL: 260 return __ops_write_mpi(output, key->key.elgamal.p) && 261 __ops_write_mpi(output, key->key.elgamal.g) && 262 __ops_write_mpi(output, key->key.elgamal.y); 263 264 default: 265 (void) fprintf(stderr, 266 "write_pubkey_body: bad algorithm\n"); 267 break; 268 } 269 return 0; 270 } 271 272 /* 273 * Note that we support v3 keys here because they're needed for 274 * verification. 275 */ 276 static unsigned 277 write_seckey_body(const __ops_seckey_t *key, 278 const uint8_t *passphrase, 279 const size_t pplen, 280 __ops_output_t *output) 281 { 282 /* RFC4880 Section 5.5.3 Secret-Key Packet Formats */ 283 284 __ops_crypt_t crypted; 285 __ops_hash_t hash; 286 unsigned done = 0; 287 unsigned i = 0; 288 uint8_t hashed[OPS_SHA1_HASH_SIZE]; 289 uint8_t sesskey[CAST_KEY_LENGTH]; 290 291 if (!write_pubkey_body(&key->pubkey, output)) { 292 return 0; 293 } 294 if (key->s2k_usage != OPS_S2KU_ENCRYPTED_AND_HASHED) { 295 (void) fprintf(stderr, "write_seckey_body: s2k usage\n"); 296 return 0; 297 } 298 if (!__ops_write_scalar(output, (unsigned)key->s2k_usage, 1)) { 299 return 0; 300 } 301 302 if (key->alg != OPS_SA_CAST5) { 303 (void) fprintf(stderr, "write_seckey_body: algorithm\n"); 304 return 0; 305 } 306 if (!__ops_write_scalar(output, (unsigned)key->alg, 1)) { 307 return 0; 308 } 309 310 if (key->s2k_specifier != OPS_S2KS_SIMPLE && 311 key->s2k_specifier != OPS_S2KS_SALTED) { 312 /* = 1 \todo could also be iterated-and-salted */ 313 (void) fprintf(stderr, "write_seckey_body: s2k spec\n"); 314 return 0; 315 } 316 if (!__ops_write_scalar(output, (unsigned)key->s2k_specifier, 1)) { 317 return 0; 318 } 319 if (!__ops_write_scalar(output, (unsigned)key->hash_alg, 1)) { 320 return 0; 321 } 322 323 switch (key->s2k_specifier) { 324 case OPS_S2KS_SIMPLE: 325 /* nothing more to do */ 326 break; 327 328 case OPS_S2KS_SALTED: 329 /* 8-octet salt value */ 330 __ops_random(__UNCONST(&key->salt[0]), OPS_SALT_SIZE); 331 if (!__ops_write(output, key->salt, OPS_SALT_SIZE)) { 332 return 0; 333 } 334 break; 335 336 /* 337 * \todo case OPS_S2KS_ITERATED_AND_SALTED: // 8-octet salt 338 * value // 1-octet count break; 339 */ 340 341 default: 342 (void) fprintf(stderr, 343 "invalid/unsupported s2k specifier %d\n", 344 key->s2k_specifier); 345 return 0; 346 } 347 348 if (!__ops_write(output, &key->iv[0], __ops_block_size(key->alg))) { 349 return 0; 350 } 351 352 /* 353 * create the session key for encrypting the algorithm-specific 354 * fields 355 */ 356 357 switch (key->s2k_specifier) { 358 case OPS_S2KS_SIMPLE: 359 case OPS_S2KS_SALTED: 360 /* RFC4880: section 3.7.1.1 and 3.7.1.2 */ 361 362 for (done = 0, i = 0; done < CAST_KEY_LENGTH; i++) { 363 unsigned j; 364 uint8_t zero = 0; 365 int needed; 366 int size; 367 368 needed = CAST_KEY_LENGTH - done; 369 size = MIN(needed, OPS_SHA1_HASH_SIZE); 370 371 __ops_hash_any(&hash, key->hash_alg); 372 if (!hash.init(&hash)) { 373 (void) fprintf(stderr, "write_seckey_body: bad alloc\n"); 374 return 0; 375 } 376 377 /* preload if iterating */ 378 for (j = 0; j < i; j++) { 379 /* 380 * Coverity shows a DEADCODE error on this 381 * line. This is expected since the hardcoded 382 * use of SHA1 and CAST5 means that it will 383 * not used. This will change however when 384 * other algorithms are supported. 385 */ 386 hash.add(&hash, &zero, 1); 387 } 388 389 if (key->s2k_specifier == OPS_S2KS_SALTED) { 390 hash.add(&hash, key->salt, OPS_SALT_SIZE); 391 } 392 hash.add(&hash, passphrase, (unsigned)pplen); 393 hash.finish(&hash, hashed); 394 395 /* 396 * if more in hash than is needed by session key, use 397 * the leftmost octets 398 */ 399 (void) memcpy(&sesskey[i * OPS_SHA1_HASH_SIZE], 400 hashed, (unsigned)size); 401 done += (unsigned)size; 402 if (done > CAST_KEY_LENGTH) { 403 (void) fprintf(stderr, 404 "write_seckey_body: short add\n"); 405 return 0; 406 } 407 } 408 409 break; 410 411 /* 412 * \todo case OPS_S2KS_ITERATED_AND_SALTED: * 8-octet salt 413 * value * 1-octet count break; 414 */ 415 416 default: 417 (void) fprintf(stderr, 418 "invalid/unsupported s2k specifier %d\n", 419 key->s2k_specifier); 420 return 0; 421 } 422 423 /* use this session key to encrypt */ 424 425 __ops_crypt_any(&crypted, key->alg); 426 crypted.set_iv(&crypted, key->iv); 427 crypted.set_crypt_key(&crypted, sesskey); 428 __ops_encrypt_init(&crypted); 429 430 if (__ops_get_debug_level(__FILE__)) { 431 hexdump(stderr, "writing: iv=", key->iv, __ops_block_size(key->alg)); 432 hexdump(stderr, "key= ", sesskey, CAST_KEY_LENGTH); 433 (void) fprintf(stderr, "\nturning encryption on...\n"); 434 } 435 __ops_push_enc_crypt(output, &crypted); 436 437 switch (key->pubkey.alg) { 438 /* case OPS_PKA_DSA: */ 439 /* return __ops_write_mpi(output, key->key.dsa.x); */ 440 441 case OPS_PKA_RSA: 442 case OPS_PKA_RSA_ENCRYPT_ONLY: 443 case OPS_PKA_RSA_SIGN_ONLY: 444 445 if (!__ops_write_mpi(output, key->key.rsa.d) || 446 !__ops_write_mpi(output, key->key.rsa.p) || 447 !__ops_write_mpi(output, key->key.rsa.q) || 448 !__ops_write_mpi(output, key->key.rsa.u)) { 449 if (__ops_get_debug_level(__FILE__)) { 450 (void) fprintf(stderr, 451 "4 x mpi not written - problem\n"); 452 } 453 return 0; 454 } 455 break; 456 case OPS_PKA_DSA: 457 return __ops_write_mpi(output, key->key.dsa.x); 458 case OPS_PKA_ELGAMAL: 459 return __ops_write_mpi(output, key->key.elgamal.x); 460 default: 461 return 0; 462 } 463 464 if (!__ops_write(output, key->checkhash, OPS_CHECKHASH_SIZE)) { 465 return 0; 466 } 467 468 __ops_writer_pop(output); 469 470 return 1; 471 } 472 473 /** 474 * \ingroup Core_WritePackets 475 * \brief Writes a Public Key packet 476 * \param key 477 * \param output 478 * \return 1 if OK, otherwise 0 479 */ 480 static unsigned 481 write_struct_pubkey(__ops_output_t *output, const __ops_pubkey_t *key) 482 { 483 return __ops_write_ptag(output, OPS_PTAG_CT_PUBLIC_KEY) && 484 __ops_write_length(output, 1 + 4 + 1 + pubkey_length(key)) && 485 write_pubkey_body(key, output); 486 } 487 488 489 /** 490 \ingroup HighLevel_KeyWrite 491 492 \brief Writes a transferable PGP public key to the given output stream. 493 494 \param keydata Key to be written 495 \param armoured Flag is set for armoured output 496 \param output Output stream 497 498 */ 499 500 unsigned 501 __ops_write_xfer_pubkey(__ops_output_t *output, 502 const __ops_key_t *key, 503 const unsigned armoured) 504 { 505 unsigned i, j; 506 507 if (armoured) { 508 __ops_writer_push_armoured(output, OPS_PGP_PUBLIC_KEY_BLOCK); 509 } 510 /* public key */ 511 if (!write_struct_pubkey(output, &key->key.pubkey)) { 512 return 0; 513 } 514 515 /* TODO: revocation signatures go here */ 516 517 /* user ids and corresponding signatures */ 518 for (i = 0; i < key->uidc; i++) { 519 if (!__ops_write_struct_userid(output, key->uids[i])) { 520 return 0; 521 } 522 for (j = 0; j < key->packetc; j++) { 523 if (!__ops_write(output, key->packets[j].raw, (unsigned)key->packets[j].length)) { 524 return 0; 525 } 526 } 527 } 528 529 /* TODO: user attributes and corresponding signatures */ 530 531 /* 532 * subkey packets and corresponding signatures and optional 533 * revocation 534 */ 535 536 if (armoured) { 537 __ops_writer_info_finalise(&output->errors, &output->writer); 538 __ops_writer_pop(output); 539 } 540 return 1; 541 } 542 543 /** 544 \ingroup HighLevel_KeyWrite 545 546 \brief Writes a transferable PGP secret key to the given output stream. 547 548 \param keydata Key to be written 549 \param passphrase 550 \param pplen 551 \param armoured Flag is set for armoured output 552 \param output Output stream 553 554 */ 555 556 unsigned 557 __ops_write_xfer_seckey(__ops_output_t *output, 558 const __ops_key_t *key, 559 const uint8_t *passphrase, 560 const size_t pplen, 561 unsigned armoured) 562 { 563 unsigned i, j; 564 565 if (armoured) { 566 __ops_writer_push_armoured(output, OPS_PGP_PRIVATE_KEY_BLOCK); 567 } 568 /* public key */ 569 if (!__ops_write_struct_seckey(&key->key.seckey, passphrase, 570 pplen, output)) { 571 return 0; 572 } 573 574 /* TODO: revocation signatures go here */ 575 576 /* user ids and corresponding signatures */ 577 for (i = 0; i < key->uidc; i++) { 578 if (!__ops_write_struct_userid(output, key->uids[i])) { 579 return 0; 580 } 581 for (j = 0; j < key->packetc; j++) { 582 if (!__ops_write(output, key->packets[j].raw, (unsigned)key->packets[j].length)) { 583 return 0; 584 } 585 } 586 } 587 588 /* TODO: user attributes and corresponding signatures */ 589 590 /* 591 * subkey packets and corresponding signatures and optional 592 * revocation 593 */ 594 595 if (armoured) { 596 __ops_writer_info_finalise(&output->errors, &output->writer); 597 __ops_writer_pop(output); 598 } 599 return 1; 600 } 601 602 /** 603 * \ingroup Core_WritePackets 604 * \brief Writes one RSA public key packet. 605 * \param t Creation time 606 * \param n RSA public modulus 607 * \param e RSA public encryption exponent 608 * \param output Writer settings 609 * 610 * \return 1 if OK, otherwise 0 611 */ 612 613 unsigned 614 __ops_write_rsa_pubkey(time_t t, const BIGNUM *n, 615 const BIGNUM *e, 616 __ops_output_t *output) 617 { 618 __ops_pubkey_t key; 619 620 __ops_fast_create_rsa_pubkey(&key, t, __UNCONST(n), __UNCONST(e)); 621 return write_struct_pubkey(output, &key); 622 } 623 624 /** 625 * \ingroup Core_Create 626 * \param out 627 * \param key 628 * \param make_packet 629 */ 630 631 void 632 __ops_build_pubkey(__ops_memory_t *out, const __ops_pubkey_t *key, 633 unsigned make_packet) 634 { 635 __ops_output_t *output; 636 637 output = __ops_output_new(); 638 __ops_memory_init(out, 128); 639 __ops_writer_set_memory(output, out); 640 write_pubkey_body(key, output); 641 if (make_packet) { 642 __ops_memory_make_packet(out, OPS_PTAG_CT_PUBLIC_KEY); 643 } 644 __ops_output_delete(output); 645 } 646 647 /** 648 * \ingroup Core_Create 649 * 650 * Create an RSA secret key structure. If a parameter is marked as 651 * [OPTIONAL], then it can be omitted and will be calculated from 652 * other params - or, in the case of e, will default to 0x10001. 653 * 654 * Parameters are _not_ copied, so will be freed if the structure is 655 * freed. 656 * 657 * \param key The key structure to be initialised. 658 * \param t 659 * \param d The RSA parameter d (=e^-1 mod (p-1)(q-1)) [OPTIONAL] 660 * \param p The RSA parameter p 661 * \param q The RSA parameter q (q > p) 662 * \param u The RSA parameter u (=p^-1 mod q) [OPTIONAL] 663 * \param n The RSA public parameter n (=p*q) [OPTIONAL] 664 * \param e The RSA public parameter e */ 665 666 void 667 __ops_fast_create_rsa_seckey(__ops_seckey_t *key, time_t t, 668 BIGNUM *d, BIGNUM *p, BIGNUM *q, BIGNUM *u, 669 BIGNUM *n, BIGNUM *e) 670 { 671 __ops_fast_create_rsa_pubkey(&key->pubkey, t, n, e); 672 673 /* XXX: calculate optionals */ 674 key->key.rsa.d = d; 675 key->key.rsa.p = p; 676 key->key.rsa.q = q; 677 key->key.rsa.u = u; 678 679 key->s2k_usage = OPS_S2KU_NONE; 680 681 /* XXX: sanity check and add errors... */ 682 } 683 684 /** 685 * \ingroup Core_WritePackets 686 * \brief Writes a Secret Key packet. 687 * \param key The secret key 688 * \param passphrase The passphrase 689 * \param pplen Length of passphrase 690 * \param output 691 * \return 1 if OK; else 0 692 */ 693 unsigned 694 __ops_write_struct_seckey(const __ops_seckey_t *key, 695 const uint8_t *passphrase, 696 const size_t pplen, 697 __ops_output_t *output) 698 { 699 int length = 0; 700 701 if (key->pubkey.version != 4) { 702 (void) fprintf(stderr, 703 "__ops_write_struct_seckey: public key version\n"); 704 return 0; 705 } 706 707 /* Ref: RFC4880 Section 5.5.3 */ 708 709 /* pubkey, excluding MPIs */ 710 length += 1 + 4 + 1 + 1; 711 712 /* s2k usage */ 713 length += 1; 714 715 switch (key->s2k_usage) { 716 case OPS_S2KU_NONE: 717 /* nothing to add */ 718 break; 719 720 case OPS_S2KU_ENCRYPTED_AND_HASHED: /* 254 */ 721 case OPS_S2KU_ENCRYPTED: /* 255 */ 722 723 /* Ref: RFC4880 Section 3.7 */ 724 length += 1; /* s2k_specifier */ 725 726 switch (key->s2k_specifier) { 727 case OPS_S2KS_SIMPLE: 728 length += 1; /* hash algorithm */ 729 break; 730 731 case OPS_S2KS_SALTED: 732 length += 1 + 8; /* hash algorithm + salt */ 733 break; 734 735 case OPS_S2KS_ITERATED_AND_SALTED: 736 length += 1 + 8 + 1; /* hash algorithm, salt + 737 * count */ 738 break; 739 740 default: 741 (void) fprintf(stderr, 742 "__ops_write_struct_seckey: s2k spec\n"); 743 return 0; 744 } 745 break; 746 747 default: 748 (void) fprintf(stderr, 749 "__ops_write_struct_seckey: s2k usage\n"); 750 return 0; 751 } 752 753 /* IV */ 754 if (key->s2k_usage) { 755 length += __ops_block_size(key->alg); 756 } 757 /* checksum or hash */ 758 switch (key->s2k_usage) { 759 case OPS_S2KU_NONE: 760 case OPS_S2KU_ENCRYPTED: 761 length += 2; 762 break; 763 764 case OPS_S2KU_ENCRYPTED_AND_HASHED: 765 length += OPS_CHECKHASH_SIZE; 766 break; 767 768 default: 769 (void) fprintf(stderr, 770 "__ops_write_struct_seckey: s2k cksum usage\n"); 771 return 0; 772 } 773 774 /* secret key and public key MPIs */ 775 length += (unsigned)seckey_length(key); 776 777 return __ops_write_ptag(output, OPS_PTAG_CT_SECRET_KEY) && 778 /* __ops_write_length(output,1+4+1+1+seckey_length(key)+2) && */ 779 __ops_write_length(output, (unsigned)length) && 780 write_seckey_body(key, passphrase, pplen, output); 781 } 782 783 /** 784 * \ingroup Core_Create 785 * 786 * \brief Create a new __ops_output_t structure. 787 * 788 * \return the new structure. 789 * \note It is the responsiblity of the caller to call __ops_output_delete(). 790 * \sa __ops_output_delete() 791 */ 792 __ops_output_t * 793 __ops_output_new(void) 794 { 795 return calloc(1, sizeof(__ops_output_t)); 796 } 797 798 /** 799 * \ingroup Core_Create 800 * \brief Delete an __ops_output_t strucut and associated resources. 801 * 802 * Delete an __ops_output_t structure. If a writer is active, then 803 * that is also deleted. 804 * 805 * \param info the structure to be deleted. 806 */ 807 void 808 __ops_output_delete(__ops_output_t *output) 809 { 810 __ops_writer_info_delete(&output->writer); 811 free(output); 812 } 813 814 /** 815 \ingroup Core_Create 816 \brief Calculate the checksum for a session key 817 \param sesskey Session Key to use 818 \param cs Checksum to be written 819 \return 1 if OK; else 0 820 */ 821 unsigned 822 __ops_calc_sesskey_checksum(__ops_pk_sesskey_t *sesskey, uint8_t cs[2]) 823 { 824 uint32_t checksum = 0; 825 unsigned i; 826 827 if (!__ops_is_sa_supported(sesskey->symm_alg)) { 828 return 0; 829 } 830 831 for (i = 0; i < __ops_key_size(sesskey->symm_alg); i++) { 832 checksum += sesskey->key[i]; 833 } 834 checksum = checksum % 65536; 835 836 cs[0] = (uint8_t)((checksum >> 8) & 0xff); 837 cs[1] = (uint8_t)(checksum & 0xff); 838 839 if (__ops_get_debug_level(__FILE__)) { 840 hexdump(stderr, "nm buf checksum:", cs, 2); 841 } 842 return 1; 843 } 844 845 static unsigned 846 create_unencoded_m_buf(__ops_pk_sesskey_t *sesskey, uint8_t *m_buf) 847 { 848 int i; 849 850 /* m_buf is the buffer which will be encoded in PKCS#1 block */ 851 /* encoding to form the "m" value used in the */ 852 /* Public Key Encrypted Session Key Packet */ 853 /* 854 * as defined in RFC Section 5.1 "Public-Key Encrypted Session Key 855 * Packet" 856 */ 857 858 m_buf[0] = sesskey->symm_alg; 859 860 if (sesskey->symm_alg != OPS_SA_CAST5) { 861 (void) fprintf(stderr, "create_unencoded_m_buf: symm alg\n"); 862 return 0; 863 } 864 for (i = 0; i < CAST_KEY_LENGTH; i++) { 865 /* XXX - Flexelint - Warning 679: Suspicious Truncation in arithmetic expression combining with pointer */ 866 m_buf[1 + i] = sesskey->key[i]; 867 } 868 869 return (__ops_calc_sesskey_checksum(sesskey, 870 m_buf + 1 + CAST_KEY_LENGTH)); 871 } 872 873 /** 874 \ingroup Core_Create 875 \brief implementation of EME-PKCS1-v1_5-ENCODE, as defined in OpenPGP RFC 876 \param M 877 \param mLen 878 \param pubkey 879 \param EM 880 \return 1 if OK; else 0 881 */ 882 unsigned 883 encode_m_buf(const uint8_t *M, size_t mLen, const __ops_pubkey_t * pubkey, 884 uint8_t *EM) 885 { 886 unsigned k; 887 unsigned i; 888 889 /* implementation of EME-PKCS1-v1_5-ENCODE, as defined in OpenPGP RFC */ 890 switch (pubkey->alg) { 891 case OPS_PKA_RSA: 892 break; 893 case OPS_PKA_DSA: 894 case OPS_PKA_ELGAMAL: 895 (void) fprintf(stderr, "encode_m_buf: DSA/Elgamal encryption not implemented yet\n"); 896 break; 897 default: 898 (void) fprintf(stderr, "encode_m_buf: pubkey algorithm\n"); 899 return 0; 900 } 901 902 k = (unsigned)BN_num_bytes(pubkey->key.rsa.n); 903 if (mLen > k - 11) { 904 (void) fprintf(stderr, "encode_m_buf: message too long\n"); 905 return 0; 906 } 907 /* these two bytes defined by RFC */ 908 EM[0] = 0x00; 909 EM[1] = 0x02; 910 911 /* add non-zero random bytes of length k - mLen -3 */ 912 for (i = 2; i < (k - mLen) - 1; ++i) { 913 do { 914 __ops_random(EM + i, 1); 915 } while (EM[i] == 0); 916 } 917 918 if (i < 8 + 2) { 919 (void) fprintf(stderr, "encode_m_buf: bad i len\n"); 920 return 0; 921 } 922 923 EM[i++] = 0; 924 925 (void) memcpy(EM + i, M, mLen); 926 927 if (__ops_get_debug_level(__FILE__)) { 928 hexdump(stderr, "Encoded Message:", EM, mLen); 929 } 930 return 1; 931 } 932 933 /** 934 \ingroup Core_Create 935 \brief Creates an __ops_pk_sesskey_t struct from keydata 936 \param key Keydata to use 937 \return __ops_pk_sesskey_t struct 938 \note It is the caller's responsiblity to free the returned pointer 939 \note Currently hard-coded to use CAST5 940 \note Currently hard-coded to use RSA 941 */ 942 __ops_pk_sesskey_t * 943 __ops_create_pk_sesskey(const __ops_key_t *key) 944 { 945 /* 946 * Creates a random session key and encrypts it for the given key 947 * 948 * Session Key is for use with a SK algo, 949 * can be any, we're hardcoding CAST5 for now 950 * 951 * Encryption used is PK, 952 * can be any, we're hardcoding RSA for now 953 */ 954 955 #define SZ_UNENCODED_M_BUF (CAST_KEY_LENGTH + 1 + 2) 956 957 const __ops_pubkey_t *pubkey; 958 __ops_pk_sesskey_t *sesskey; 959 const uint8_t *id; 960 uint8_t unencoded_m_buf[SZ_UNENCODED_M_BUF]; 961 uint8_t *encoded_m_buf; 962 size_t sz_encoded_m_buf; 963 964 if (memcmp(key->encid, "\0\0\0\0\0\0\0\0", 8) == 0) { 965 pubkey = __ops_get_pubkey(key); 966 id = key->sigid; 967 } else { 968 pubkey = &key->enckey; 969 id = key->encid; 970 } 971 sz_encoded_m_buf = BN_num_bytes(pubkey->key.rsa.n); 972 if ((encoded_m_buf = calloc(1, sz_encoded_m_buf)) == NULL) { 973 (void) fprintf(stderr, 974 "__ops_create_pk_sesskey: can't allocate\n"); 975 return NULL; 976 } 977 if ((sesskey = calloc(1, sizeof(*sesskey))) == NULL) { 978 (void) fprintf(stderr, 979 "__ops_create_pk_sesskey: can't allocate\n"); 980 free(encoded_m_buf); 981 return NULL; 982 } 983 if (key->type != OPS_PTAG_CT_PUBLIC_KEY) { 984 (void) fprintf(stderr, 985 "__ops_create_pk_sesskey: bad type\n"); 986 free(encoded_m_buf); 987 free(sesskey); 988 return NULL; 989 } 990 sesskey->version = OPS_PKSK_V3; 991 (void) memcpy(sesskey->key_id, id, sizeof(sesskey->key_id)); 992 993 if (__ops_get_debug_level(__FILE__)) { 994 hexdump(stderr, "Encrypting for RSA keyid", id, sizeof(sesskey->key_id)); 995 } 996 switch (pubkey->alg) { 997 case OPS_PKA_RSA: 998 case OPS_PKA_DSA: 999 case OPS_PKA_ELGAMAL: 1000 break; 1001 default: 1002 (void) fprintf(stderr, 1003 "__ops_create_pk_sesskey: bad pubkey algorithm\n"); 1004 free(encoded_m_buf); 1005 free(sesskey); 1006 return NULL; 1007 } 1008 sesskey->alg = pubkey->alg; 1009 1010 /* \todo allow user to specify other algorithm */ 1011 sesskey->symm_alg = OPS_SA_CAST5; 1012 __ops_random(sesskey->key, CAST_KEY_LENGTH); 1013 1014 if (__ops_get_debug_level(__FILE__)) { 1015 hexdump(stderr, "CAST5 sesskey created", sesskey->key, CAST_KEY_LENGTH); 1016 } 1017 if (create_unencoded_m_buf(sesskey, &unencoded_m_buf[0]) == 0) { 1018 free(encoded_m_buf); 1019 free(sesskey); 1020 return NULL; 1021 } 1022 if (__ops_get_debug_level(__FILE__)) { 1023 hexdump(stderr, "uuencoded m buf", unencoded_m_buf, SZ_UNENCODED_M_BUF); 1024 } 1025 encode_m_buf(unencoded_m_buf, SZ_UNENCODED_M_BUF, pubkey, encoded_m_buf); 1026 1027 /* and encrypt it */ 1028 switch (key->key.pubkey.alg) { 1029 case OPS_PKA_RSA: 1030 if (!__ops_rsa_encrypt_mpi(encoded_m_buf, sz_encoded_m_buf, pubkey, 1031 &sesskey->params)) { 1032 free(encoded_m_buf); 1033 free(sesskey); 1034 return NULL; 1035 } 1036 break; 1037 case OPS_PKA_DSA: 1038 case OPS_PKA_ELGAMAL: 1039 (void) fprintf(stderr, "DSA/Elgamal encryption not supported yet\n"); 1040 free(encoded_m_buf); 1041 free(sesskey); 1042 return NULL; 1043 default: 1044 /* will not get here - for lint only */ 1045 break; 1046 } 1047 free(encoded_m_buf); 1048 return sesskey; 1049 } 1050 1051 /** 1052 \ingroup Core_WritePackets 1053 \brief Writes Public Key Session Key packet 1054 \param info Write settings 1055 \param pksk Public Key Session Key to write out 1056 \return 1 if OK; else 0 1057 */ 1058 unsigned 1059 __ops_write_pk_sesskey(__ops_output_t *output, __ops_pk_sesskey_t *pksk) 1060 { 1061 /* XXX - Flexelint - Pointer parameter 'pksk' (line 1076) could be declared as pointing to const */ 1062 if (pksk == NULL) { 1063 (void) fprintf(stderr, 1064 "__ops_write_pk_sesskey: NULL pksk\n"); 1065 return 0; 1066 } 1067 switch (pksk->alg) { 1068 case OPS_PKA_RSA: 1069 return __ops_write_ptag(output, OPS_PTAG_CT_PK_SESSION_KEY) && 1070 __ops_write_length(output, (unsigned)(1 + 8 + 1 + 1071 BN_num_bytes(pksk->params.rsa.encrypted_m) + 2)) && 1072 __ops_write_scalar(output, (unsigned)pksk->version, 1) && 1073 __ops_write(output, pksk->key_id, 8) && 1074 __ops_write_scalar(output, (unsigned)pksk->alg, 1) && 1075 __ops_write_mpi(output, pksk->params.rsa.encrypted_m) 1076 /* ?? && __ops_write_scalar(output, 0, 2); */ 1077 ; 1078 case OPS_PKA_DSA: 1079 case OPS_PKA_ELGAMAL: 1080 (void) fprintf(stderr, "__ops_write_pk_sesskey: DSA/Elgamal encryption not implemented yet\n"); 1081 return 0; 1082 default: 1083 (void) fprintf(stderr, 1084 "__ops_write_pk_sesskey: bad algorithm\n"); 1085 return 0; 1086 } 1087 } 1088 1089 /** 1090 \ingroup Core_WritePackets 1091 \brief Writes MDC packet 1092 \param hashed Hash for MDC 1093 \param output Write settings 1094 \return 1 if OK; else 0 1095 */ 1096 1097 unsigned 1098 __ops_write_mdc(__ops_output_t *output, const uint8_t *hashed) 1099 { 1100 /* write it out */ 1101 return __ops_write_ptag(output, OPS_PTAG_CT_MDC) && 1102 __ops_write_length(output, OPS_SHA1_HASH_SIZE) && 1103 __ops_write(output, hashed, OPS_SHA1_HASH_SIZE); 1104 } 1105 1106 /** 1107 \ingroup Core_WritePackets 1108 \brief Writes Literal Data packet from buffer 1109 \param data Buffer to write out 1110 \param maxlen Max length of buffer 1111 \param type Literal Data Type 1112 \param output Write settings 1113 \return 1 if OK; else 0 1114 */ 1115 unsigned 1116 __ops_write_litdata(__ops_output_t *output, 1117 const uint8_t *data, 1118 const int maxlen, 1119 const __ops_litdata_enum type) 1120 { 1121 /* 1122 * RFC4880 does not specify a meaning for filename or date. 1123 * It is implementation-dependent. 1124 * We will not implement them. 1125 */ 1126 /* \todo do we need to check text data for <cr><lf> line endings ? */ 1127 return __ops_write_ptag(output, OPS_PTAG_CT_LITDATA) && 1128 __ops_write_length(output, (unsigned)(1 + 1 + 4 + maxlen)) && 1129 __ops_write_scalar(output, (unsigned)type, 1) && 1130 __ops_write_scalar(output, 0, 1) && 1131 __ops_write_scalar(output, 0, 4) && 1132 __ops_write(output, data, (unsigned)maxlen); 1133 } 1134 1135 /** 1136 \ingroup Core_WritePackets 1137 \brief Writes Literal Data packet from contents of file 1138 \param filename Name of file to read from 1139 \param type Literal Data Type 1140 \param output Write settings 1141 \return 1 if OK; else 0 1142 */ 1143 1144 unsigned 1145 __ops_fileread_litdata(const char *filename, 1146 const __ops_litdata_enum type, 1147 __ops_output_t *output) 1148 { 1149 __ops_memory_t *mem; 1150 unsigned ret; 1151 int len; 1152 1153 mem = __ops_memory_new(); 1154 if (!__ops_mem_readfile(mem, filename)) { 1155 (void) fprintf(stderr, "__ops_mem_readfile of '%s' failed\n", filename); 1156 return 0; 1157 } 1158 len = (int)__ops_mem_len(mem); 1159 ret = __ops_write_litdata(output, __ops_mem_data(mem), len, type); 1160 __ops_memory_free(mem); 1161 return ret; 1162 } 1163 1164 /** 1165 \ingroup HighLevel_General 1166 1167 \brief Writes contents of buffer into file 1168 1169 \param filename Filename to write to 1170 \param buf Buffer to write to file 1171 \param len Size of buffer 1172 \param overwrite Flag to set whether to overwrite an existing file 1173 \return 1 if OK; 0 if error 1174 */ 1175 1176 int 1177 __ops_filewrite(const char *filename, const char *buf, 1178 const size_t len, const unsigned overwrite) 1179 { 1180 int flags; 1181 int fd; 1182 1183 flags = O_WRONLY | O_CREAT; 1184 if (overwrite) { 1185 flags |= O_TRUNC; 1186 } else { 1187 flags |= O_EXCL; 1188 } 1189 #ifdef O_BINARY 1190 flags |= O_BINARY; 1191 #endif 1192 fd = open(filename, flags, 0600); 1193 if (fd < 0) { 1194 (void) fprintf(stderr, "can't open '%s'\n", filename); 1195 return 0; 1196 } 1197 if (write(fd, buf, len) != (int)len) { 1198 (void) close(fd); 1199 return 0; 1200 } 1201 1202 return (close(fd) == 0); 1203 } 1204 1205 /** 1206 \ingroup Core_WritePackets 1207 \brief Write Symmetrically Encrypted packet 1208 \param data Data to encrypt 1209 \param len Length of data 1210 \param output Write settings 1211 \return 1 if OK; else 0 1212 \note Hard-coded to use AES256 1213 */ 1214 unsigned 1215 __ops_write_symm_enc_data(const uint8_t *data, 1216 const int len, 1217 __ops_output_t * output) 1218 { 1219 __ops_crypt_t crypt_info; 1220 uint8_t *encrypted = (uint8_t *) NULL; 1221 size_t encrypted_sz; 1222 int done = 0; 1223 1224 /* \todo assume AES256 for now */ 1225 __ops_crypt_any(&crypt_info, OPS_SA_AES_256); 1226 __ops_encrypt_init(&crypt_info); 1227 1228 encrypted_sz = (size_t)(len + crypt_info.blocksize + 2); 1229 if ((encrypted = calloc(1, encrypted_sz)) == NULL) { 1230 (void) fprintf(stderr, "can't allocate %" PRIsize "d\n", 1231 encrypted_sz); 1232 return 0; 1233 } 1234 1235 done = (int)__ops_encrypt_se(&crypt_info, encrypted, data, (unsigned)len); 1236 if (done != len) { 1237 (void) fprintf(stderr, 1238 "__ops_write_symm_enc_data: done != len\n"); 1239 return 0; 1240 } 1241 1242 return __ops_write_ptag(output, OPS_PTAG_CT_SE_DATA) && 1243 __ops_write_length(output, (unsigned)(1 + encrypted_sz)) && 1244 __ops_write(output, data, (unsigned)len); 1245 } 1246 1247 /** 1248 \ingroup Core_WritePackets 1249 \brief Write a One Pass Signature packet 1250 \param seckey Secret Key to use 1251 \param hash_alg Hash Algorithm to use 1252 \param sig_type Signature type 1253 \param output Write settings 1254 \return 1 if OK; else 0 1255 */ 1256 unsigned 1257 __ops_write_one_pass_sig(__ops_output_t *output, 1258 const __ops_seckey_t *seckey, 1259 const __ops_hash_alg_t hash_alg, 1260 const __ops_sig_type_t sig_type) 1261 { 1262 uint8_t keyid[OPS_KEY_ID_SIZE]; 1263 1264 __ops_keyid(keyid, OPS_KEY_ID_SIZE, &seckey->pubkey, OPS_HASH_SHA1); /* XXX - hardcoded */ 1265 return __ops_write_ptag(output, OPS_PTAG_CT_1_PASS_SIG) && 1266 __ops_write_length(output, 1 + 1 + 1 + 1 + 8 + 1) && 1267 __ops_write_scalar(output, 3, 1) /* version */ && 1268 __ops_write_scalar(output, (unsigned)sig_type, 1) && 1269 __ops_write_scalar(output, (unsigned)hash_alg, 1) && 1270 __ops_write_scalar(output, (unsigned)seckey->pubkey.alg, 1) && 1271 __ops_write(output, keyid, 8) && 1272 __ops_write_scalar(output, 1, 1); 1273 } 1274