xref: /netbsd-src/crypto/external/bsd/heimdal/dist/lib/hx509/ks_file.c (revision 413d532bcc3f62d122e56d92e13ac64825a40baf)
1 /*	$NetBSD: ks_file.c,v 1.1.1.2 2014/04/24 12:45:41 pettai Exp $	*/
2 
3 /*
4  * Copyright (c) 2005 - 2007 Kungliga Tekniska Högskolan
5  * (Royal Institute of Technology, Stockholm, Sweden).
6  * All rights reserved.
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  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * 3. Neither the name of the Institute nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include "hx_locl.h"
37 
38 typedef enum { USE_PEM, USE_DER } outformat;
39 
40 struct ks_file {
41     hx509_certs certs;
42     char *fn;
43     outformat format;
44 };
45 
46 /*
47  *
48  */
49 
50 static int
51 parse_certificate(hx509_context context, const char *fn,
52 		  struct hx509_collector *c,
53 		  const hx509_pem_header *headers,
54 		  const void *data, size_t len,
55 		  const AlgorithmIdentifier *ai)
56 {
57     hx509_cert cert;
58     int ret;
59 
60     ret = hx509_cert_init_data(context, data, len, &cert);
61     if (ret)
62 	return ret;
63 
64     ret = _hx509_collector_certs_add(context, c, cert);
65     hx509_cert_free(cert);
66     return ret;
67 }
68 
69 static int
70 try_decrypt(hx509_context context,
71 	    struct hx509_collector *collector,
72 	    const AlgorithmIdentifier *alg,
73 	    const EVP_CIPHER *c,
74 	    const void *ivdata,
75 	    const void *password,
76 	    size_t passwordlen,
77 	    const void *cipher,
78 	    size_t len)
79 {
80     heim_octet_string clear;
81     size_t keylen;
82     void *key;
83     int ret;
84 
85     keylen = EVP_CIPHER_key_length(c);
86 
87     key = malloc(keylen);
88     if (key == NULL) {
89 	hx509_clear_error_string(context);
90 	return ENOMEM;
91     }
92 
93     ret = EVP_BytesToKey(c, EVP_md5(), ivdata,
94 			 password, passwordlen,
95 			 1, key, NULL);
96     if (ret <= 0) {
97 	hx509_set_error_string(context, 0, HX509_CRYPTO_INTERNAL_ERROR,
98 			       "Failed to do string2key for private key");
99 	return HX509_CRYPTO_INTERNAL_ERROR;
100     }
101 
102     clear.data = malloc(len);
103     if (clear.data == NULL) {
104 	hx509_set_error_string(context, 0, ENOMEM,
105 			       "Out of memory to decrypt for private key");
106 	ret = ENOMEM;
107 	goto out;
108     }
109     clear.length = len;
110 
111     {
112 	EVP_CIPHER_CTX ctx;
113 	EVP_CIPHER_CTX_init(&ctx);
114 	EVP_CipherInit_ex(&ctx, c, NULL, key, ivdata, 0);
115 	EVP_Cipher(&ctx, clear.data, cipher, len);
116 	EVP_CIPHER_CTX_cleanup(&ctx);
117     }
118 
119     ret = _hx509_collector_private_key_add(context,
120 					   collector,
121 					   alg,
122 					   NULL,
123 					   &clear,
124 					   NULL);
125 
126     memset(clear.data, 0, clear.length);
127     free(clear.data);
128 out:
129     memset(key, 0, keylen);
130     free(key);
131     return ret;
132 }
133 
134 static int
135 parse_pkcs8_private_key(hx509_context context, const char *fn,
136 			struct hx509_collector *c,
137 			const hx509_pem_header *headers,
138 			const void *data, size_t length,
139 			const AlgorithmIdentifier *ai)
140 {
141     PKCS8PrivateKeyInfo ki;
142     heim_octet_string keydata;
143 
144     int ret;
145 
146     ret = decode_PKCS8PrivateKeyInfo(data, length, &ki, NULL);
147     if (ret)
148 	return ret;
149 
150     keydata.data = rk_UNCONST(data);
151     keydata.length = length;
152 
153     ret = _hx509_collector_private_key_add(context,
154 					   c,
155 					   &ki.privateKeyAlgorithm,
156 					   NULL,
157 					   &ki.privateKey,
158 					   &keydata);
159     free_PKCS8PrivateKeyInfo(&ki);
160     return ret;
161 }
162 
163 static int
164 parse_pem_private_key(hx509_context context, const char *fn,
165 		      struct hx509_collector *c,
166 		      const hx509_pem_header *headers,
167 		      const void *data, size_t len,
168 		      const AlgorithmIdentifier *ai)
169 {
170     int ret = 0;
171     const char *enc;
172 
173     enc = hx509_pem_find_header(headers, "Proc-Type");
174     if (enc) {
175 	const char *dek;
176 	char *type, *iv;
177 	ssize_t ssize, size;
178 	void *ivdata;
179 	const EVP_CIPHER *cipher;
180 	const struct _hx509_password *pw;
181 	hx509_lock lock;
182 	int decrypted = 0;
183 	size_t i;
184 
185 	lock = _hx509_collector_get_lock(c);
186 	if (lock == NULL) {
187 	    hx509_set_error_string(context, 0, HX509_ALG_NOT_SUPP,
188 				   "Failed to get password for "
189 				   "password protected file %s", fn);
190 	    return HX509_ALG_NOT_SUPP;
191 	}
192 
193 	if (strcmp(enc, "4,ENCRYPTED") != 0) {
194 	    hx509_set_error_string(context, 0, HX509_PARSING_KEY_FAILED,
195 				   "Private key encrypted in unknown method %s "
196 				   "in file",
197 				   enc, fn);
198 	    hx509_clear_error_string(context);
199 	    return HX509_PARSING_KEY_FAILED;
200 	}
201 
202 	dek = hx509_pem_find_header(headers, "DEK-Info");
203 	if (dek == NULL) {
204 	    hx509_set_error_string(context, 0, HX509_PARSING_KEY_FAILED,
205 				   "Encrypted private key missing DEK-Info");
206 	    return HX509_PARSING_KEY_FAILED;
207 	}
208 
209 	type = strdup(dek);
210 	if (type == NULL) {
211 	    hx509_clear_error_string(context);
212 	    return ENOMEM;
213 	}
214 
215 	iv = strchr(type, ',');
216 	if (iv == NULL) {
217 	    free(type);
218 	    hx509_set_error_string(context, 0, HX509_PARSING_KEY_FAILED,
219 				   "IV missing");
220 	    return HX509_PARSING_KEY_FAILED;
221 	}
222 
223 	*iv++ = '\0';
224 
225 	size = strlen(iv);
226 	ivdata = malloc(size);
227 	if (ivdata == NULL) {
228 	    hx509_clear_error_string(context);
229 	    free(type);
230 	    return ENOMEM;
231 	}
232 
233 	cipher = EVP_get_cipherbyname(type);
234 	if (cipher == NULL) {
235 	    free(ivdata);
236 	    hx509_set_error_string(context, 0, HX509_ALG_NOT_SUPP,
237 				   "Private key encrypted with "
238 				   "unsupported cipher: %s",
239 				   type);
240 	    free(type);
241 	    return HX509_ALG_NOT_SUPP;
242 	}
243 
244 #define PKCS5_SALT_LEN 8
245 
246 	ssize = hex_decode(iv, ivdata, size);
247 	free(type);
248 	type = NULL;
249 	iv = NULL;
250 
251 	if (ssize < 0 || ssize < PKCS5_SALT_LEN || ssize < EVP_CIPHER_iv_length(cipher)) {
252 	    free(ivdata);
253 	    hx509_set_error_string(context, 0, HX509_PARSING_KEY_FAILED,
254 				   "Salt have wrong length in "
255 				   "private key file");
256 	    return HX509_PARSING_KEY_FAILED;
257 	}
258 
259 	pw = _hx509_lock_get_passwords(lock);
260 	if (pw != NULL) {
261 	    const void *password;
262 	    size_t passwordlen;
263 
264 	    for (i = 0; i < pw->len; i++) {
265 		password = pw->val[i];
266 		passwordlen = strlen(password);
267 
268 		ret = try_decrypt(context, c, ai, cipher, ivdata,
269 				  password, passwordlen, data, len);
270 		if (ret == 0) {
271 		    decrypted = 1;
272 		    break;
273 		}
274 	    }
275 	}
276 	if (!decrypted) {
277 	    hx509_prompt prompt;
278 	    char password[128];
279 
280 	    memset(&prompt, 0, sizeof(prompt));
281 
282 	    prompt.prompt = "Password for keyfile: ";
283 	    prompt.type = HX509_PROMPT_TYPE_PASSWORD;
284 	    prompt.reply.data = password;
285 	    prompt.reply.length = sizeof(password);
286 
287 	    ret = hx509_lock_prompt(lock, &prompt);
288 	    if (ret == 0)
289 		ret = try_decrypt(context, c, ai, cipher, ivdata, password,
290 				  strlen(password), data, len);
291 	    /* XXX add password to lock password collection ? */
292 	    memset(password, 0, sizeof(password));
293 	}
294 	free(ivdata);
295 
296     } else {
297 	heim_octet_string keydata;
298 
299 	keydata.data = rk_UNCONST(data);
300 	keydata.length = len;
301 
302 	ret = _hx509_collector_private_key_add(context, c, ai, NULL,
303 					       &keydata, NULL);
304     }
305 
306     return ret;
307 }
308 
309 
310 struct pem_formats {
311     const char *name;
312     int (*func)(hx509_context, const char *, struct hx509_collector *,
313 		const hx509_pem_header *, const void *, size_t,
314 		const AlgorithmIdentifier *);
315     const AlgorithmIdentifier *(*ai)(void);
316 } formats[] = {
317     { "CERTIFICATE", parse_certificate, NULL },
318     { "PRIVATE KEY", parse_pkcs8_private_key, NULL },
319     { "RSA PRIVATE KEY", parse_pem_private_key, hx509_signature_rsa },
320     { "EC PRIVATE KEY", parse_pem_private_key, hx509_signature_ecPublicKey }
321 };
322 
323 
324 struct pem_ctx {
325     int flags;
326     struct hx509_collector *c;
327 };
328 
329 static int
330 pem_func(hx509_context context, const char *type,
331 	 const hx509_pem_header *header,
332 	 const void *data, size_t len, void *ctx)
333 {
334     struct pem_ctx *pem_ctx = (struct pem_ctx*)ctx;
335     int ret = 0;
336     size_t j;
337 
338     for (j = 0; j < sizeof(formats)/sizeof(formats[0]); j++) {
339 	const char *q = formats[j].name;
340 	if (strcasecmp(type, q) == 0) {
341 	    const AlgorithmIdentifier *ai = NULL;
342 	    if (formats[j].ai != NULL)
343 		ai = (*formats[j].ai)();
344 
345 	    ret = (*formats[j].func)(context, NULL, pem_ctx->c,
346 				     header, data, len, ai);
347 	    if (ret && (pem_ctx->flags & HX509_CERTS_UNPROTECT_ALL)) {
348 		hx509_set_error_string(context, HX509_ERROR_APPEND, ret,
349 				       "Failed parseing PEM format %s", type);
350 		return ret;
351 	    }
352 	    break;
353 	}
354     }
355     if (j == sizeof(formats)/sizeof(formats[0])) {
356 	ret = HX509_UNSUPPORTED_OPERATION;
357 	hx509_set_error_string(context, 0, ret,
358 			       "Found no matching PEM format for %s", type);
359 	return ret;
360     }
361     return 0;
362 }
363 
364 /*
365  *
366  */
367 
368 static int
369 file_init_common(hx509_context context,
370 		 hx509_certs certs, void **data, int flags,
371 		 const char *residue, hx509_lock lock, outformat format)
372 {
373     char *p, *pnext;
374     struct ks_file *ksf = NULL;
375     hx509_private_key *keys = NULL;
376     int ret;
377     struct pem_ctx pem_ctx;
378 
379     pem_ctx.flags = flags;
380     pem_ctx.c = NULL;
381 
382     *data = NULL;
383 
384     if (lock == NULL)
385 	lock = _hx509_empty_lock;
386 
387     ksf = calloc(1, sizeof(*ksf));
388     if (ksf == NULL) {
389 	hx509_clear_error_string(context);
390 	return ENOMEM;
391     }
392     ksf->format = format;
393 
394     ksf->fn = strdup(residue);
395     if (ksf->fn == NULL) {
396 	hx509_clear_error_string(context);
397 	ret = ENOMEM;
398 	goto out;
399     }
400 
401     /*
402      * XXX this is broken, the function should parse the file before
403      * overwriting it
404      */
405 
406     if (flags & HX509_CERTS_CREATE) {
407 	ret = hx509_certs_init(context, "MEMORY:ks-file-create",
408 			       0, lock, &ksf->certs);
409 	if (ret)
410 	    goto out;
411 	*data = ksf;
412 	return 0;
413     }
414 
415     ret = _hx509_collector_alloc(context, lock, &pem_ctx.c);
416     if (ret)
417 	goto out;
418 
419     for (p = ksf->fn; p != NULL; p = pnext) {
420 	FILE *f;
421 
422 	pnext = strchr(p, ',');
423 	if (pnext)
424 	    *pnext++ = '\0';
425 
426 
427 	if ((f = fopen(p, "r")) == NULL) {
428 	    ret = ENOENT;
429 	    hx509_set_error_string(context, 0, ret,
430 				   "Failed to open PEM file \"%s\": %s",
431 				   p, strerror(errno));
432 	    goto out;
433 	}
434 	rk_cloexec_file(f);
435 
436 	ret = hx509_pem_read(context, f, pem_func, &pem_ctx);
437 	fclose(f);
438 	if (ret != 0 && ret != HX509_PARSING_KEY_FAILED)
439 	    goto out;
440 	else if (ret == HX509_PARSING_KEY_FAILED) {
441 	    size_t length;
442 	    void *ptr;
443 	    size_t i;
444 
445 	    ret = rk_undumpdata(p, &ptr, &length);
446 	    if (ret) {
447 		hx509_clear_error_string(context);
448 		goto out;
449 	    }
450 
451 	    for (i = 0; i < sizeof(formats)/sizeof(formats[0]); i++) {
452 		const AlgorithmIdentifier *ai = NULL;
453 		if (formats[i].ai != NULL)
454 		    ai = (*formats[i].ai)();
455 
456 		ret = (*formats[i].func)(context, p, pem_ctx.c, NULL, ptr, length, ai);
457 		if (ret == 0)
458 		    break;
459 	    }
460 	    rk_xfree(ptr);
461 	    if (ret) {
462 		hx509_clear_error_string(context);
463 		goto out;
464 	    }
465 	}
466     }
467 
468     ret = _hx509_collector_collect_certs(context, pem_ctx.c, &ksf->certs);
469     if (ret)
470 	goto out;
471 
472     ret = _hx509_collector_collect_private_keys(context, pem_ctx.c, &keys);
473     if (ret == 0) {
474 	int i;
475 
476 	for (i = 0; keys[i]; i++)
477 	    _hx509_certs_keys_add(context, ksf->certs, keys[i]);
478 	_hx509_certs_keys_free(context, keys);
479     }
480 
481 out:
482     if (ret == 0)
483 	*data = ksf;
484     else {
485 	if (ksf->fn)
486 	    free(ksf->fn);
487 	free(ksf);
488     }
489     if (pem_ctx.c)
490 	_hx509_collector_free(pem_ctx.c);
491 
492     return ret;
493 }
494 
495 static int
496 file_init_pem(hx509_context context,
497 	      hx509_certs certs, void **data, int flags,
498 	      const char *residue, hx509_lock lock)
499 {
500     return file_init_common(context, certs, data, flags, residue, lock, USE_PEM);
501 }
502 
503 static int
504 file_init_der(hx509_context context,
505 	      hx509_certs certs, void **data, int flags,
506 	      const char *residue, hx509_lock lock)
507 {
508     return file_init_common(context, certs, data, flags, residue, lock, USE_DER);
509 }
510 
511 static int
512 file_free(hx509_certs certs, void *data)
513 {
514     struct ks_file *ksf = data;
515     hx509_certs_free(&ksf->certs);
516     free(ksf->fn);
517     free(ksf);
518     return 0;
519 }
520 
521 struct store_ctx {
522     FILE *f;
523     outformat format;
524 };
525 
526 static int
527 store_func(hx509_context context, void *ctx, hx509_cert c)
528 {
529     struct store_ctx *sc = ctx;
530     heim_octet_string data;
531     int ret;
532 
533     ret = hx509_cert_binary(context, c, &data);
534     if (ret)
535 	return ret;
536 
537     switch (sc->format) {
538     case USE_DER:
539 	fwrite(data.data, data.length, 1, sc->f);
540 	free(data.data);
541 	break;
542     case USE_PEM:
543 	hx509_pem_write(context, "CERTIFICATE", NULL, sc->f,
544 			data.data, data.length);
545 	free(data.data);
546 	if (_hx509_cert_private_key_exportable(c)) {
547 	    hx509_private_key key = _hx509_cert_private_key(c);
548 	    ret = _hx509_private_key_export(context, key,
549 					    HX509_KEY_FORMAT_DER, &data);
550 	    if (ret)
551 		break;
552 	    hx509_pem_write(context, _hx509_private_pem_name(key), NULL, sc->f,
553 			    data.data, data.length);
554 	    free(data.data);
555 	}
556 	break;
557     }
558 
559     return 0;
560 }
561 
562 static int
563 file_store(hx509_context context,
564 	   hx509_certs certs, void *data, int flags, hx509_lock lock)
565 {
566     struct ks_file *ksf = data;
567     struct store_ctx sc;
568     int ret;
569 
570     sc.f = fopen(ksf->fn, "w");
571     if (sc.f == NULL) {
572 	hx509_set_error_string(context, 0, ENOENT,
573 			       "Failed to open file %s for writing");
574 	return ENOENT;
575     }
576     rk_cloexec_file(sc.f);
577     sc.format = ksf->format;
578 
579     ret = hx509_certs_iter_f(context, ksf->certs, store_func, &sc);
580     fclose(sc.f);
581     return ret;
582 }
583 
584 static int
585 file_add(hx509_context context, hx509_certs certs, void *data, hx509_cert c)
586 {
587     struct ks_file *ksf = data;
588     return hx509_certs_add(context, ksf->certs, c);
589 }
590 
591 static int
592 file_iter_start(hx509_context context,
593 		hx509_certs certs, void *data, void **cursor)
594 {
595     struct ks_file *ksf = data;
596     return hx509_certs_start_seq(context, ksf->certs, cursor);
597 }
598 
599 static int
600 file_iter(hx509_context context,
601 	  hx509_certs certs, void *data, void *iter, hx509_cert *cert)
602 {
603     struct ks_file *ksf = data;
604     return hx509_certs_next_cert(context, ksf->certs, iter, cert);
605 }
606 
607 static int
608 file_iter_end(hx509_context context,
609 	      hx509_certs certs,
610 	      void *data,
611 	      void *cursor)
612 {
613     struct ks_file *ksf = data;
614     return hx509_certs_end_seq(context, ksf->certs, cursor);
615 }
616 
617 static int
618 file_getkeys(hx509_context context,
619 	     hx509_certs certs,
620 	     void *data,
621 	     hx509_private_key **keys)
622 {
623     struct ks_file *ksf = data;
624     return _hx509_certs_keys_get(context, ksf->certs, keys);
625 }
626 
627 static int
628 file_addkey(hx509_context context,
629 	     hx509_certs certs,
630 	     void *data,
631 	     hx509_private_key key)
632 {
633     struct ks_file *ksf = data;
634     return _hx509_certs_keys_add(context, ksf->certs, key);
635 }
636 
637 static struct hx509_keyset_ops keyset_file = {
638     "FILE",
639     0,
640     file_init_pem,
641     file_store,
642     file_free,
643     file_add,
644     NULL,
645     file_iter_start,
646     file_iter,
647     file_iter_end,
648     NULL,
649     file_getkeys,
650     file_addkey
651 };
652 
653 static struct hx509_keyset_ops keyset_pemfile = {
654     "PEM-FILE",
655     0,
656     file_init_pem,
657     file_store,
658     file_free,
659     file_add,
660     NULL,
661     file_iter_start,
662     file_iter,
663     file_iter_end,
664     NULL,
665     file_getkeys,
666     file_addkey
667 };
668 
669 static struct hx509_keyset_ops keyset_derfile = {
670     "DER-FILE",
671     0,
672     file_init_der,
673     file_store,
674     file_free,
675     file_add,
676     NULL,
677     file_iter_start,
678     file_iter,
679     file_iter_end,
680     NULL,
681     file_getkeys,
682     file_addkey
683 };
684 
685 
686 void
687 _hx509_ks_file_register(hx509_context context)
688 {
689     _hx509_ks_register(context, &keyset_file);
690     _hx509_ks_register(context, &keyset_pemfile);
691     _hx509_ks_register(context, &keyset_derfile);
692 }
693