pluto and scepclient use private and public key plugins of libstrongswan
[strongswan.git] / src / libstrongswan / plugins / gmp / gmp_rsa_public_key.c
1 /*
2 * Copyright (C) 2005-2008 Martin Willi
3 * Copyright (C) 2005 Jan Hutter
4 * Hochschule fuer Technik Rapperswil
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; either version 2 of the License, or (at your
9 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
10 *
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
13 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * for more details.
15 */
16
17 #include <gmp.h>
18 #include <sys/stat.h>
19 #include <unistd.h>
20 #include <stdio.h>
21 #include <string.h>
22
23 #include "gmp_rsa_public_key.h"
24
25 #include <debug.h>
26 #include <asn1/oid.h>
27 #include <asn1/asn1.h>
28 #include <asn1/asn1_parser.h>
29 #include <asn1/pem.h>
30 #include <crypto/hashers/hasher.h>
31 #include <pgp/pgp.h>
32
33 typedef struct private_gmp_rsa_public_key_t private_gmp_rsa_public_key_t;
34
35 /**
36 * Private data structure with signing context.
37 */
38 struct private_gmp_rsa_public_key_t {
39 /**
40 * Public interface for this signer.
41 */
42 gmp_rsa_public_key_t public;
43
44 /**
45 * Public modulus.
46 */
47 mpz_t n;
48
49 /**
50 * Public exponent.
51 */
52 mpz_t e;
53
54 /**
55 * Keysize in bytes.
56 */
57 size_t k;
58
59 /**
60 * Keyid formed as a SHA-1 hash of a publicKeyInfo object
61 */
62 identification_t *keyid_info;
63
64 /**
65 * Keyid formed as a SHA-1 hash of a publicKey object
66 */
67 identification_t *keyid;
68
69 /**
70 * reference counter
71 */
72 refcount_t ref;
73 };
74
75 /**
76 * Shared functions defined in gmp_rsa_private_key.c
77 */
78 extern chunk_t gmp_mpz_to_chunk(const mpz_t value);
79 extern chunk_t gmp_mpz_to_asn1(const mpz_t value);
80
81 /**
82 * RSAEP algorithm specified in PKCS#1.
83 */
84 static chunk_t rsaep(private_gmp_rsa_public_key_t *this, chunk_t data)
85 {
86 mpz_t m, c;
87 chunk_t encrypted;
88
89 mpz_init(c);
90 mpz_init(m);
91
92 mpz_import(m, data.len, 1, 1, 1, 0, data.ptr);
93
94 mpz_powm(c, m, this->e, this->n);
95
96 encrypted.len = this->k;
97 encrypted.ptr = mpz_export(NULL, NULL, 1, encrypted.len, 1, 0, c);
98 if (encrypted.ptr == NULL)
99 {
100 encrypted.len = 0;
101 }
102
103 mpz_clear(c);
104 mpz_clear(m);
105
106 return encrypted;
107 }
108
109 /**
110 * RSAVP1 algorithm specified in PKCS#1.
111 */
112 static chunk_t rsavp1(private_gmp_rsa_public_key_t *this, chunk_t data)
113 {
114 return rsaep(this, data);
115 }
116
117 /**
118 * ASN.1 definition of digestInfo
119 */
120 static const asn1Object_t digestInfoObjects[] = {
121 { 0, "digestInfo", ASN1_SEQUENCE, ASN1_OBJ }, /* 0 */
122 { 1, "digestAlgorithm", ASN1_EOC, ASN1_RAW }, /* 1 */
123 { 1, "digest", ASN1_OCTET_STRING, ASN1_BODY }, /* 2 */
124 { 0, "exit", ASN1_EOC, ASN1_EXIT }
125 };
126 #define DIGEST_INFO 0
127 #define DIGEST_INFO_ALGORITHM 1
128 #define DIGEST_INFO_DIGEST 2
129
130 /**
131 * Verification of an EMPSA PKCS1 signature described in PKCS#1
132 */
133 static bool verify_emsa_pkcs1_signature(private_gmp_rsa_public_key_t *this,
134 hash_algorithm_t algorithm,
135 chunk_t data, chunk_t signature)
136 {
137 chunk_t em_ori, em;
138 bool success = FALSE;
139
140 /* remove any preceding 0-bytes from signature */
141 while (signature.len && *(signature.ptr) == 0x00)
142 {
143 signature.len -= 1;
144 signature.ptr++;
145 }
146
147 if (signature.len > this->k)
148 {
149 return INVALID_ARG;
150 }
151
152 /* unpack signature */
153 em_ori = em = rsavp1(this, signature);
154
155 /* result should look like this:
156 * EM = 0x00 || 0x01 || PS || 0x00 || T.
157 * PS = 0xFF padding, with length to fill em
158 * T = oid || hash
159 */
160
161 /* check magic bytes */
162 if (*(em.ptr) != 0x00 || *(em.ptr+1) != 0x01)
163 {
164 goto end;
165 }
166 em.ptr += 2;
167 em.len -= 2;
168
169 /* find magic 0x00 */
170 while (em.len > 0)
171 {
172 if (*em.ptr == 0x00)
173 {
174 /* found magic byte, stop */
175 em.ptr++;
176 em.len--;
177 break;
178 }
179 else if (*em.ptr != 0xFF)
180 {
181 /* bad padding, decryption failed ?!*/
182 goto end;
183 }
184 em.ptr++;
185 em.len--;
186 }
187
188 if (em.len == 0)
189 {
190 /* no digestInfo found */
191 goto end;
192 }
193
194 if (algorithm == HASH_UNKNOWN)
195 { /* IKEv1 signatures without digestInfo */
196 if (em.len != data.len)
197 {
198 DBG1("hash size in signature is %u bytes instead of %u bytes",
199 em.len, data.len);
200 goto end;
201 }
202 success = memeq(em.ptr, data.ptr, data.len);
203 }
204 else
205 { /* IKEv2 and X.509 certificate signatures */
206 asn1_parser_t *parser;
207 chunk_t object;
208 int objectID;
209 hash_algorithm_t hash_algorithm = HASH_UNKNOWN;
210
211 DBG2("signature verification:");
212 parser = asn1_parser_create(digestInfoObjects, em);
213
214 while (parser->iterate(parser, &objectID, &object))
215 {
216 switch (objectID)
217 {
218 case DIGEST_INFO:
219 {
220 if (em.len > object.len)
221 {
222 DBG1("digestInfo field in signature is followed by %u surplus bytes",
223 em.len - object.len);
224 goto end_parser;
225 }
226 break;
227 }
228 case DIGEST_INFO_ALGORITHM:
229 {
230 int hash_oid = asn1_parse_algorithmIdentifier(object,
231 parser->get_level(parser)+1, NULL);
232
233 hash_algorithm = hasher_algorithm_from_oid(hash_oid);
234 if (hash_algorithm == HASH_UNKNOWN || hash_algorithm != algorithm)
235 {
236 DBG1("expected hash algorithm %N, but found %N (OID: %#B)",
237 hash_algorithm_names, algorithm,
238 hash_algorithm_names, hash_algorithm, &object);
239 goto end_parser;
240 }
241 break;
242 }
243 case DIGEST_INFO_DIGEST:
244 {
245 chunk_t hash;
246 hasher_t *hasher;
247
248 hasher = lib->crypto->create_hasher(lib->crypto, hash_algorithm);
249 if (hasher == NULL)
250 {
251 DBG1("hash algorithm %N not supported",
252 hash_algorithm_names, hash_algorithm);
253 goto end_parser;
254 }
255
256 if (object.len != hasher->get_hash_size(hasher))
257 {
258 DBG1("hash size in signature is %u bytes instead of %u "
259 "bytes", object.len, hasher->get_hash_size(hasher));
260 hasher->destroy(hasher);
261 goto end_parser;
262 }
263
264 /* build our own hash and compare */
265 hasher->allocate_hash(hasher, data, &hash);
266 hasher->destroy(hasher);
267 success = memeq(object.ptr, hash.ptr, hash.len);
268 free(hash.ptr);
269 break;
270 }
271 default:
272 break;
273 }
274 }
275
276 end_parser:
277 success &= parser->success(parser);
278 parser->destroy(parser);
279 }
280
281 end:
282 free(em_ori.ptr);
283 return success;
284 }
285
286 /**
287 * Implementation of public_key_t.get_type.
288 */
289 static key_type_t get_type(private_gmp_rsa_public_key_t *this)
290 {
291 return KEY_RSA;
292 }
293
294 /**
295 * Implementation of public_key_t.verify.
296 */
297 static bool verify(private_gmp_rsa_public_key_t *this, signature_scheme_t scheme,
298 chunk_t data, chunk_t signature)
299 {
300 switch (scheme)
301 {
302 case SIGN_DEFAULT:
303 case SIGN_RSA_EMSA_PKCS1_NULL:
304 return verify_emsa_pkcs1_signature(this, HASH_UNKNOWN, data, signature);
305 case SIGN_RSA_EMSA_PKCS1_MD5:
306 return verify_emsa_pkcs1_signature(this, HASH_MD5, data, signature);
307 case SIGN_RSA_EMSA_PKCS1_SHA1:
308 return verify_emsa_pkcs1_signature(this, HASH_SHA1, data, signature);
309 case SIGN_RSA_EMSA_PKCS1_SHA256:
310 return verify_emsa_pkcs1_signature(this, HASH_SHA256, data, signature);
311 case SIGN_RSA_EMSA_PKCS1_SHA384:
312 return verify_emsa_pkcs1_signature(this, HASH_SHA384, data, signature);
313 case SIGN_RSA_EMSA_PKCS1_SHA512:
314 return verify_emsa_pkcs1_signature(this, HASH_SHA512, data, signature);
315 default:
316 DBG1("signature scheme %N not supported in RSA",
317 signature_scheme_names, scheme);
318 return FALSE;
319 }
320 }
321
322 /**
323 * Implementation of public_key_t.get_keysize.
324 */
325 static bool encrypt_(private_gmp_rsa_public_key_t *this, chunk_t crypto, chunk_t *plain)
326 {
327 DBG1("RSA public key encryption not implemented");
328 return FALSE;
329 }
330
331 /**
332 * Implementation of gmp_rsa_public_key.equals.
333 */
334 static bool equals(private_gmp_rsa_public_key_t *this, public_key_t *other)
335 {
336 identification_t *keyid;
337
338 if (&this->public.interface == other)
339 {
340 return TRUE;
341 }
342 if (other->get_type(other) != KEY_RSA)
343 {
344 return FALSE;
345 }
346 keyid = other->get_id(other, ID_PUBKEY_SHA1);
347 if (keyid && keyid->equals(keyid, this->keyid))
348 {
349 return TRUE;
350 }
351 keyid = other->get_id(other, ID_PUBKEY_INFO_SHA1);
352 if (keyid && keyid->equals(keyid, this->keyid_info))
353 {
354 return TRUE;
355 }
356 return FALSE;
357 }
358
359 /**
360 * Implementation of public_key_t.get_keysize.
361 */
362 static size_t get_keysize(private_gmp_rsa_public_key_t *this)
363 {
364 return this->k;
365 }
366
367 /**
368 * Build the PGP version 3 RSA key identifier from n and e using
369 * MD5 hashed modulus and exponent. Also used in rsa_private_key.c.
370 */
371 static identification_t* gmp_rsa_build_pgp_v3_keyid(mpz_t n, mpz_t e)
372 {
373 identification_t *keyid;
374 chunk_t modulus, exponent, hash;
375 hasher_t *hasher;
376
377 hasher= lib->crypto->create_hasher(lib->crypto, HASH_MD5);
378 if (hasher == NULL)
379 {
380 DBG1("computation of PGP V3 key ID failed, no MD5 hasher is available");
381 return NULL;
382 }
383 modulus = gmp_mpz_to_chunk(n);
384 exponent = gmp_mpz_to_chunk(e);
385 hasher->allocate_hash(hasher, modulus, NULL);
386 hasher->allocate_hash(hasher, exponent, &hash);
387 hasher->destroy(hasher);
388 keyid = identification_create_from_encoding(ID_PUBKEY_SHA1, hash);
389 free(hash.ptr);
390 free(modulus.ptr);
391 free(exponent.ptr);
392 return keyid;
393 }
394
395 /**
396 * Implementation of public_key_t.get_id.
397 */
398 static identification_t *get_id(private_gmp_rsa_public_key_t *this,
399 id_type_t type)
400 {
401 switch (type)
402 {
403 case ID_PUBKEY_INFO_SHA1:
404 return this->keyid_info;
405 case ID_PUBKEY_SHA1:
406 return this->keyid;
407 case ID_KEY_ID:
408 return gmp_rsa_build_pgp_v3_keyid(this->n, this->e);
409 default:
410 return NULL;
411 }
412 }
413
414 /*
415 * Implementation of public_key_t.get_encoding.
416 */
417 static chunk_t get_encoding(private_gmp_rsa_public_key_t *this)
418 {
419 return asn1_wrap(ASN1_SEQUENCE, "mm",
420 gmp_mpz_to_asn1(this->n),
421 gmp_mpz_to_asn1(this->e));
422 }
423
424 /**
425 * Implementation of public_key_t.get_ref.
426 */
427 static private_gmp_rsa_public_key_t* get_ref(private_gmp_rsa_public_key_t *this)
428 {
429 ref_get(&this->ref);
430 return this;
431 }
432
433 /**
434 * Implementation of gmp_rsa_public_key.destroy.
435 */
436 static void destroy(private_gmp_rsa_public_key_t *this)
437 {
438 if (ref_put(&this->ref))
439 {
440 mpz_clear(this->n);
441 mpz_clear(this->e);
442 DESTROY_IF(this->keyid);
443 DESTROY_IF(this->keyid_info);
444 free(this);
445 }
446 }
447
448 /**
449 * Generic private constructor
450 */
451 static private_gmp_rsa_public_key_t *gmp_rsa_public_key_create_empty()
452 {
453 private_gmp_rsa_public_key_t *this = malloc_thing(private_gmp_rsa_public_key_t);
454
455 this->public.interface.get_type = (key_type_t (*) (public_key_t*))get_type;
456 this->public.interface.verify = (bool (*) (public_key_t*, signature_scheme_t, chunk_t, chunk_t))verify;
457 this->public.interface.encrypt = (bool (*) (public_key_t*, chunk_t, chunk_t*))encrypt_;
458 this->public.interface.equals = (bool (*) (public_key_t*, public_key_t*))equals;
459 this->public.interface.get_keysize = (size_t (*) (public_key_t*))get_keysize;
460 this->public.interface.get_id = (identification_t* (*) (public_key_t*, id_type_t))get_id;
461 this->public.interface.get_encoding = (chunk_t(*) (public_key_t*))get_encoding;
462 this->public.interface.get_ref = (public_key_t* (*) (public_key_t *this))get_ref;
463 this->public.interface.destroy = (void (*) (public_key_t *this))destroy;
464
465 this->keyid = NULL;
466 this->keyid_info = NULL;
467 this->ref = 1;
468
469 return this;
470 }
471
472 /**
473 * Build the RSA key identifier from n and e using SHA1 hashed publicKey(Info).
474 * Also used in rsa_private_key.c.
475 */
476 bool gmp_rsa_public_key_build_id(mpz_t n, mpz_t e, identification_t **keyid,
477 identification_t **keyid_info)
478 {
479 chunk_t publicKeyInfo, publicKey, hash;
480 hasher_t *hasher;
481
482 hasher = lib->crypto->create_hasher(lib->crypto, HASH_SHA1);
483 if (hasher == NULL)
484 {
485 DBG1("SHA1 hash algorithm not supported, unable to use RSA");
486 return FALSE;
487 }
488 publicKey = asn1_wrap(ASN1_SEQUENCE, "mm",
489 gmp_mpz_to_asn1(n),
490 gmp_mpz_to_asn1(e));
491 hasher->allocate_hash(hasher, publicKey, &hash);
492 *keyid = identification_create_from_encoding(ID_PUBKEY_SHA1, hash);
493 chunk_free(&hash);
494
495 publicKeyInfo = asn1_wrap(ASN1_SEQUENCE, "cm",
496 asn1_algorithmIdentifier(OID_RSA_ENCRYPTION),
497 asn1_bitstring("m", publicKey));
498 hasher->allocate_hash(hasher, publicKeyInfo, &hash);
499 *keyid_info = identification_create_from_encoding(ID_PUBKEY_INFO_SHA1, hash);
500 chunk_free(&hash);
501
502 hasher->destroy(hasher);
503 chunk_free(&publicKeyInfo);
504
505 return TRUE;
506 }
507
508 /**
509 * Create a public key from mpz values, used in gmp_rsa_private_key
510 */
511 gmp_rsa_public_key_t *gmp_rsa_public_key_create_from_n_e(mpz_t n, mpz_t e)
512 {
513 private_gmp_rsa_public_key_t *this = gmp_rsa_public_key_create_empty();
514
515 mpz_init_set(this->n, n);
516 mpz_init_set(this->e, e);
517
518 this->k = (mpz_sizeinbase(this->n, 2) + 7) / BITS_PER_BYTE;
519 if (!gmp_rsa_public_key_build_id(this->n, this->e,
520 &this->keyid, &this->keyid_info))
521 {
522 destroy(this);
523 return NULL;
524 }
525 return &this->public;
526 }
527
528 /**
529 * ASN.1 definition of RSApublicKey
530 */
531 static const asn1Object_t pubkeyObjects[] = {
532 { 0, "RSAPublicKey", ASN1_SEQUENCE, ASN1_OBJ }, /* 0 */
533 { 1, "modulus", ASN1_INTEGER, ASN1_BODY }, /* 1 */
534 { 1, "publicExponent", ASN1_INTEGER, ASN1_BODY }, /* 2 */
535 { 0, "exit", ASN1_EOC, ASN1_EXIT }
536 };
537 #define PUB_KEY_RSA_PUBLIC_KEY 0
538 #define PUB_KEY_MODULUS 1
539 #define PUB_KEY_EXPONENT 2
540
541 /**
542 * Load a public key from an ASN.1 encoded blob
543 */
544 static gmp_rsa_public_key_t *load_asn1_der(chunk_t blob)
545 {
546 asn1_parser_t *parser;
547 chunk_t object;
548 int objectID;
549 bool success = FALSE;
550
551 private_gmp_rsa_public_key_t *this = gmp_rsa_public_key_create_empty();
552
553 mpz_init(this->n);
554 mpz_init(this->e);
555
556 parser = asn1_parser_create(pubkeyObjects, blob);
557
558 while (parser->iterate(parser, &objectID, &object))
559 {
560 switch (objectID)
561 {
562 case PUB_KEY_MODULUS:
563 mpz_import(this->n, object.len, 1, 1, 1, 0, object.ptr);
564 break;
565 case PUB_KEY_EXPONENT:
566 mpz_import(this->e, object.len, 1, 1, 1, 0, object.ptr);
567 break;
568 }
569 }
570 success = parser->success(parser);
571 free(blob.ptr);
572 parser->destroy(parser);
573
574 if (!success)
575 {
576 destroy(this);
577 return NULL;
578 }
579
580 this->k = (mpz_sizeinbase(this->n, 2) + 7) / BITS_PER_BYTE;
581
582 if (!gmp_rsa_public_key_build_id(this->n, this->e,
583 &this->keyid, &this->keyid_info))
584 {
585 destroy(this);
586 return NULL;
587 }
588 return &this->public;
589 }
590
591 /**
592 * Load a public key from an OpenPGP blob
593 */
594 static gmp_rsa_public_key_t* load_pgp(chunk_t blob)
595 {
596 chunk_t exponent, modulus;
597 chunk_t packet = blob;
598 private_gmp_rsa_public_key_t *this = gmp_rsa_public_key_create_empty();
599
600 mpz_init(this->n);
601 mpz_init(this->e);
602
603 /* modulus n */
604 modulus.len = (pgp_length(&packet, 2) + 7) / BITS_PER_BYTE;
605 modulus.ptr = packet.ptr;
606 if (modulus.len > packet.len)
607 {
608 DBG1("OpenPGP public key blob too short for modulus");
609 goto end;
610 }
611 packet.ptr += modulus.len;
612 packet.len -= modulus.len;
613 DBG2("L3 - modulus:");
614 DBG3("%B", &modulus);
615
616 /* public exponent e */
617 exponent.len = (pgp_length(&packet, 2) + 7) / BITS_PER_BYTE;
618 exponent.ptr = packet.ptr;
619 if (exponent.len > packet.len)
620 {
621 DBG1("OpenPGP public key blob too short for exponent");
622 goto end;
623 }
624 DBG2("L3 - public exponent:");
625 DBG3("%B", &exponent);
626
627 mpz_import(this->n, modulus.len, 1, 1, 1, 0, modulus.ptr);
628 mpz_import(this->e, exponent.len, 1, 1, 1, 0, exponent.ptr);
629 this->k = (mpz_sizeinbase(this->n, 2) + 7) / BITS_PER_BYTE;
630 free(blob.ptr);
631
632 if (!gmp_rsa_public_key_build_id(this->n, this->e,
633 &this->keyid, &this->keyid_info))
634 {
635 destroy(this);
636 return NULL;
637 }
638 return &this->public;
639
640 end:
641 free(blob.ptr);
642 destroy(this);
643 return NULL;
644 }
645
646 /**
647 * Load a public key from an RFC 3110 encoded blob
648 */
649 static gmp_rsa_public_key_t *load_rfc_3110(chunk_t blob)
650 {
651 chunk_t exponent, modulus;
652 u_char *pos = blob.ptr;
653 size_t len = blob.len;
654 private_gmp_rsa_public_key_t *this = gmp_rsa_public_key_create_empty();
655
656 mpz_init(this->n);
657 mpz_init(this->e);
658
659 if (blob.len < 3)
660 {
661 DBG1("RFC 3110 public key blob too short for exponent length");
662 goto end;
663 }
664 if (pos[0] != 0x00)
665 {
666 exponent = chunk_create(pos + 1, pos[0]);
667 pos++;
668 len--;
669 }
670 else
671 {
672 exponent = chunk_create(pos + 3, 256*pos[1] + pos[2]);
673 pos += 3;
674 len -= 3;
675 }
676 if (exponent.len > len)
677 {
678 DBG1("RFC 3110 public key blob too short for exponent");
679 goto end;
680 }
681 pos += exponent.len;
682 len -= exponent.len;
683
684 if (len == 0)
685 {
686 DBG1("RFC 3110 public key blob has zero length modulus");
687 goto end;
688 }
689 modulus = chunk_create(pos, len);
690
691 mpz_import(this->n, modulus.len, 1, 1, 1, 0, modulus.ptr);
692 mpz_import(this->e, exponent.len, 1, 1, 1, 0, exponent.ptr);
693 this->k = (mpz_sizeinbase(this->n, 2) + 7) / BITS_PER_BYTE;
694 free(blob.ptr);
695
696 if (!gmp_rsa_public_key_build_id(this->n, this->e,
697 &this->keyid, &this->keyid_info))
698 {
699 destroy(this);
700 return NULL;
701 }
702 return &this->public;
703
704 end:
705 free(blob.ptr);
706 destroy(this);
707 return NULL;
708 }
709
710 typedef struct private_builder_t private_builder_t;
711 /**
712 * Builder implementation for key loading
713 */
714 struct private_builder_t {
715 /** implements the builder interface */
716 builder_t public;
717 /** loaded public key */
718 gmp_rsa_public_key_t *key;
719 };
720
721 /**
722 * Implementation of builder_t.build
723 */
724 static gmp_rsa_public_key_t *build(private_builder_t *this)
725 {
726 gmp_rsa_public_key_t *key = this->key;
727
728 free(this);
729 return key;
730 }
731
732 /**
733 * Implementation of builder_t.add
734 */
735 static void add(private_builder_t *this, builder_part_t part, ...)
736 {
737 if (!this->key)
738 {
739 va_list args;
740 chunk_t chunk;
741
742 switch (part)
743 {
744 case BUILD_BLOB_ASN1_DER:
745 {
746 va_start(args, part);
747 chunk = va_arg(args, chunk_t);
748 this->key = load_asn1_der(chunk_clone(chunk));
749 va_end(args);
750 return;
751 }
752 case BUILD_BLOB_PGP:
753 {
754 va_start(args, part);
755 chunk = va_arg(args, chunk_t);
756 this->key = load_pgp(chunk_clone(chunk));
757 va_end(args);
758 return;
759 }
760 case BUILD_BLOB_RFC_3110:
761 {
762 va_start(args, part);
763 chunk = va_arg(args, chunk_t);
764 this->key = load_rfc_3110(chunk_clone(chunk));
765 va_end(args);
766 return;
767 }
768 default:
769 break;
770 }
771 }
772 if (this->key)
773 {
774 destroy((private_gmp_rsa_public_key_t*)this->key);
775 }
776 builder_cancel(&this->public);
777 }
778
779 /**
780 * Builder construction function
781 */
782 builder_t *gmp_rsa_public_key_builder(key_type_t type)
783 {
784 private_builder_t *this;
785
786 if (type != KEY_RSA)
787 {
788 return NULL;
789 }
790
791 this = malloc_thing(private_builder_t);
792
793 this->key = NULL;
794 this->public.add = (void(*)(builder_t *this, builder_part_t part, ...))add;
795 this->public.build = (void*(*)(builder_t *this))build;
796
797 return &this->public;
798 }
799