xref: /freebsd/crypto/heimdal/lib/hx509/ks_file.c (revision 884a2a699669ec61e2366e3e358342dbc94be24a)
1 /*
2  * Copyright (c) 2005 - 2007 Kungliga Tekniska H�gskolan
3  * (Royal Institute of Technology, Stockholm, Sweden).
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
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  * 3. Neither the name of the Institute nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include "hx_locl.h"
35 RCSID("$Id: ks_file.c 22465 2008-01-16 14:25:24Z lha $");
36 
37 typedef enum { USE_PEM, USE_DER } outformat;
38 
39 struct ks_file {
40     hx509_certs certs;
41     char *fn;
42     outformat format;
43 };
44 
45 /*
46  *
47  */
48 
49 static int
50 parse_certificate(hx509_context context, const char *fn,
51 		  struct hx509_collector *c,
52 		  const hx509_pem_header *headers,
53 		  const void *data, size_t len)
54 {
55     hx509_cert cert;
56     int ret;
57 
58     ret = hx509_cert_init_data(context, data, len, &cert);
59     if (ret)
60 	return ret;
61 
62     ret = _hx509_collector_certs_add(context, c, cert);
63     hx509_cert_free(cert);
64     return ret;
65 }
66 
67 static int
68 try_decrypt(hx509_context context,
69 	    struct hx509_collector *collector,
70 	    const AlgorithmIdentifier *alg,
71 	    const EVP_CIPHER *c,
72 	    const void *ivdata,
73 	    const void *password,
74 	    size_t passwordlen,
75 	    const void *cipher,
76 	    size_t len)
77 {
78     heim_octet_string clear;
79     size_t keylen;
80     void *key;
81     int ret;
82 
83     keylen = EVP_CIPHER_key_length(c);
84 
85     key = malloc(keylen);
86     if (key == NULL) {
87 	hx509_clear_error_string(context);
88 	return ENOMEM;
89     }
90 
91     ret = EVP_BytesToKey(c, EVP_md5(), ivdata,
92 			 password, passwordlen,
93 			 1, key, NULL);
94     if (ret <= 0) {
95 	hx509_set_error_string(context, 0, HX509_CRYPTO_INTERNAL_ERROR,
96 			       "Failed to do string2key for private key");
97 	return HX509_CRYPTO_INTERNAL_ERROR;
98     }
99 
100     clear.data = malloc(len);
101     if (clear.data == NULL) {
102 	hx509_set_error_string(context, 0, ENOMEM,
103 			       "Out of memory to decrypt for private key");
104 	ret = ENOMEM;
105 	goto out;
106     }
107     clear.length = len;
108 
109     {
110 	EVP_CIPHER_CTX ctx;
111 	EVP_CIPHER_CTX_init(&ctx);
112 	EVP_CipherInit_ex(&ctx, c, NULL, key, ivdata, 0);
113 	EVP_Cipher(&ctx, clear.data, cipher, len);
114 	EVP_CIPHER_CTX_cleanup(&ctx);
115     }
116 
117     ret = _hx509_collector_private_key_add(context,
118 					   collector,
119 					   alg,
120 					   NULL,
121 					   &clear,
122 					   NULL);
123 
124     memset(clear.data, 0, clear.length);
125     free(clear.data);
126 out:
127     memset(key, 0, keylen);
128     free(key);
129     return ret;
130 }
131 
132 static int
133 parse_rsa_private_key(hx509_context context, const char *fn,
134 		      struct hx509_collector *c,
135 		      const hx509_pem_header *headers,
136 		      const void *data, size_t len)
137 {
138     int ret = 0;
139     const char *enc;
140 
141     enc = hx509_pem_find_header(headers, "Proc-Type");
142     if (enc) {
143 	const char *dek;
144 	char *type, *iv;
145 	ssize_t ssize, size;
146 	void *ivdata;
147 	const EVP_CIPHER *cipher;
148 	const struct _hx509_password *pw;
149 	hx509_lock lock;
150 	int i, decrypted = 0;
151 
152 	lock = _hx509_collector_get_lock(c);
153 	if (lock == NULL) {
154 	    hx509_set_error_string(context, 0, HX509_ALG_NOT_SUPP,
155 				   "Failed to get password for "
156 				   "password protected file %s", fn);
157 	    return HX509_ALG_NOT_SUPP;
158 	}
159 
160 	if (strcmp(enc, "4,ENCRYPTED") != 0) {
161 	    hx509_set_error_string(context, 0, HX509_PARSING_KEY_FAILED,
162 				   "RSA key encrypted in unknown method %s "
163 				   "in file",
164 				   enc, fn);
165 	    hx509_clear_error_string(context);
166 	    return HX509_PARSING_KEY_FAILED;
167 	}
168 
169 	dek = hx509_pem_find_header(headers, "DEK-Info");
170 	if (dek == NULL) {
171 	    hx509_set_error_string(context, 0, HX509_PARSING_KEY_FAILED,
172 				   "Encrypted RSA missing DEK-Info");
173 	    return HX509_PARSING_KEY_FAILED;
174 	}
175 
176 	type = strdup(dek);
177 	if (type == NULL) {
178 	    hx509_clear_error_string(context);
179 	    return ENOMEM;
180 	}
181 
182 	iv = strchr(type, ',');
183 	if (iv == NULL) {
184 	    free(type);
185 	    hx509_set_error_string(context, 0, HX509_PARSING_KEY_FAILED,
186 				   "IV missing");
187 	    return HX509_PARSING_KEY_FAILED;
188 	}
189 
190 	*iv++ = '\0';
191 
192 	size = strlen(iv);
193 	ivdata = malloc(size);
194 	if (ivdata == NULL) {
195 	    hx509_clear_error_string(context);
196 	    free(type);
197 	    return ENOMEM;
198 	}
199 
200 	cipher = EVP_get_cipherbyname(type);
201 	if (cipher == NULL) {
202 	    free(ivdata);
203 	    hx509_set_error_string(context, 0, HX509_ALG_NOT_SUPP,
204 				   "RSA key encrypted with "
205 				   "unsupported cipher: %s",
206 				   type);
207 	    free(type);
208 	    return HX509_ALG_NOT_SUPP;
209 	}
210 
211 #define PKCS5_SALT_LEN 8
212 
213 	ssize = hex_decode(iv, ivdata, size);
214 	free(type);
215 	type = NULL;
216 	iv = NULL;
217 
218 	if (ssize < 0 || ssize < PKCS5_SALT_LEN || ssize < EVP_CIPHER_iv_length(cipher)) {
219 	    free(ivdata);
220 	    hx509_set_error_string(context, 0, HX509_PARSING_KEY_FAILED,
221 				   "Salt have wrong length in RSA key file");
222 	    return HX509_PARSING_KEY_FAILED;
223 	}
224 
225 	pw = _hx509_lock_get_passwords(lock);
226 	if (pw != NULL) {
227 	    const void *password;
228 	    size_t passwordlen;
229 
230 	    for (i = 0; i < pw->len; i++) {
231 		password = pw->val[i];
232 		passwordlen = strlen(password);
233 
234 		ret = try_decrypt(context, c, hx509_signature_rsa(),
235 				  cipher, ivdata, password, passwordlen,
236 				  data, len);
237 		if (ret == 0) {
238 		    decrypted = 1;
239 		    break;
240 		}
241 	    }
242 	}
243 	if (!decrypted) {
244 	    hx509_prompt prompt;
245 	    char password[128];
246 
247 	    memset(&prompt, 0, sizeof(prompt));
248 
249 	    prompt.prompt = "Password for keyfile: ";
250 	    prompt.type = HX509_PROMPT_TYPE_PASSWORD;
251 	    prompt.reply.data = password;
252 	    prompt.reply.length = sizeof(password);
253 
254 	    ret = hx509_lock_prompt(lock, &prompt);
255 	    if (ret == 0)
256 		ret = try_decrypt(context, c, hx509_signature_rsa(),
257 				  cipher, ivdata, password, strlen(password),
258 				  data, len);
259 	    /* XXX add password to lock password collection ? */
260 	    memset(password, 0, sizeof(password));
261 	}
262 	free(ivdata);
263 
264     } else {
265 	heim_octet_string keydata;
266 
267 	keydata.data = rk_UNCONST(data);
268 	keydata.length = len;
269 
270 	ret = _hx509_collector_private_key_add(context,
271 					       c,
272 					       hx509_signature_rsa(),
273 					       NULL,
274 					       &keydata,
275 					       NULL);
276     }
277 
278     return ret;
279 }
280 
281 
282 struct pem_formats {
283     const char *name;
284     int (*func)(hx509_context, const char *, struct hx509_collector *,
285 		const hx509_pem_header *, const void *, size_t);
286 } formats[] = {
287     { "CERTIFICATE", parse_certificate },
288     { "RSA PRIVATE KEY", parse_rsa_private_key }
289 };
290 
291 
292 struct pem_ctx {
293     int flags;
294     struct hx509_collector *c;
295 };
296 
297 static int
298 pem_func(hx509_context context, const char *type,
299 	 const hx509_pem_header *header,
300 	 const void *data, size_t len, void *ctx)
301 {
302     struct pem_ctx *pem_ctx = (struct pem_ctx*)ctx;
303     int ret = 0, j;
304 
305     for (j = 0; j < sizeof(formats)/sizeof(formats[0]); j++) {
306 	const char *q = formats[j].name;
307 	if (strcasecmp(type, q) == 0) {
308 	    ret = (*formats[j].func)(context, NULL, pem_ctx->c,  header, data, len);
309 	    if (ret == 0)
310 		break;
311 	}
312     }
313     if (j == sizeof(formats)/sizeof(formats[0])) {
314 	ret = HX509_UNSUPPORTED_OPERATION;
315 	hx509_set_error_string(context, 0, ret,
316 			       "Found no matching PEM format for %s", type);
317 	return ret;
318     }
319     if (ret && (pem_ctx->flags & HX509_CERTS_UNPROTECT_ALL))
320 	return ret;
321     return 0;
322 }
323 
324 /*
325  *
326  */
327 
328 static int
329 file_init_common(hx509_context context,
330 		 hx509_certs certs, void **data, int flags,
331 		 const char *residue, hx509_lock lock, outformat format)
332 {
333     char *p, *pnext;
334     struct ks_file *f = NULL;
335     hx509_private_key *keys = NULL;
336     int ret;
337     struct pem_ctx pem_ctx;
338 
339     pem_ctx.flags = flags;
340     pem_ctx.c = NULL;
341 
342     *data = NULL;
343 
344     if (lock == NULL)
345 	lock = _hx509_empty_lock;
346 
347     f = calloc(1, sizeof(*f));
348     if (f == NULL) {
349 	hx509_clear_error_string(context);
350 	return ENOMEM;
351     }
352     f->format = format;
353 
354     f->fn = strdup(residue);
355     if (f->fn == NULL) {
356 	hx509_clear_error_string(context);
357 	ret = ENOMEM;
358 	goto out;
359     }
360 
361     /*
362      * XXX this is broken, the function should parse the file before
363      * overwriting it
364      */
365 
366     if (flags & HX509_CERTS_CREATE) {
367 	ret = hx509_certs_init(context, "MEMORY:ks-file-create",
368 			       0, lock, &f->certs);
369 	if (ret)
370 	    goto out;
371 	*data = f;
372 	return 0;
373     }
374 
375     ret = _hx509_collector_alloc(context, lock, &pem_ctx.c);
376     if (ret)
377 	goto out;
378 
379     for (p = f->fn; p != NULL; p = pnext) {
380 	FILE *f;
381 
382 	pnext = strchr(p, ',');
383 	if (pnext)
384 	    *pnext++ = '\0';
385 
386 
387 	if ((f = fopen(p, "r")) == NULL) {
388 	    ret = ENOENT;
389 	    hx509_set_error_string(context, 0, ret,
390 				   "Failed to open PEM file \"%s\": %s",
391 				   p, strerror(errno));
392 	    goto out;
393 	}
394 
395 	ret = hx509_pem_read(context, f, pem_func, &pem_ctx);
396 	fclose(f);
397 	if (ret != 0 && ret != HX509_PARSING_KEY_FAILED)
398 	    goto out;
399 	else if (ret == HX509_PARSING_KEY_FAILED) {
400 	    size_t length;
401 	    void *ptr;
402 	    int i;
403 
404 	    ret = _hx509_map_file(p, &ptr, &length, NULL);
405 	    if (ret) {
406 		hx509_clear_error_string(context);
407 		goto out;
408 	    }
409 
410 	    for (i = 0; i < sizeof(formats)/sizeof(formats[0]); i++) {
411 		ret = (*formats[i].func)(context, p, pem_ctx.c, NULL, ptr, length);
412 		if (ret == 0)
413 		    break;
414 	    }
415 	    _hx509_unmap_file(ptr, length);
416 	    if (ret)
417 		goto out;
418 	}
419     }
420 
421     ret = _hx509_collector_collect_certs(context, pem_ctx.c, &f->certs);
422     if (ret)
423 	goto out;
424 
425     ret = _hx509_collector_collect_private_keys(context, pem_ctx.c, &keys);
426     if (ret == 0) {
427 	int i;
428 
429 	for (i = 0; keys[i]; i++)
430 	    _hx509_certs_keys_add(context, f->certs, keys[i]);
431 	_hx509_certs_keys_free(context, keys);
432     }
433 
434 out:
435     if (ret == 0)
436 	*data = f;
437     else {
438 	if (f->fn)
439 	    free(f->fn);
440 	free(f);
441     }
442     if (pem_ctx.c)
443 	_hx509_collector_free(pem_ctx.c);
444 
445     return ret;
446 }
447 
448 static int
449 file_init_pem(hx509_context context,
450 	      hx509_certs certs, void **data, int flags,
451 	      const char *residue, hx509_lock lock)
452 {
453     return file_init_common(context, certs, data, flags, residue, lock, USE_PEM);
454 }
455 
456 static int
457 file_init_der(hx509_context context,
458 	      hx509_certs certs, void **data, int flags,
459 	      const char *residue, hx509_lock lock)
460 {
461     return file_init_common(context, certs, data, flags, residue, lock, USE_DER);
462 }
463 
464 static int
465 file_free(hx509_certs certs, void *data)
466 {
467     struct ks_file *f = data;
468     hx509_certs_free(&f->certs);
469     free(f->fn);
470     free(f);
471     return 0;
472 }
473 
474 struct store_ctx {
475     FILE *f;
476     outformat format;
477 };
478 
479 static int
480 store_func(hx509_context context, void *ctx, hx509_cert c)
481 {
482     struct store_ctx *sc = ctx;
483     heim_octet_string data;
484     int ret;
485 
486     ret = hx509_cert_binary(context, c, &data);
487     if (ret)
488 	return ret;
489 
490     switch (sc->format) {
491     case USE_DER:
492 	fwrite(data.data, data.length, 1, sc->f);
493 	free(data.data);
494 	break;
495     case USE_PEM:
496 	hx509_pem_write(context, "CERTIFICATE", NULL, sc->f,
497 			data.data, data.length);
498 	free(data.data);
499 	if (_hx509_cert_private_key_exportable(c)) {
500 	    hx509_private_key key = _hx509_cert_private_key(c);
501 	    ret = _hx509_private_key_export(context, key, &data);
502 	    if (ret)
503 		break;
504 	    hx509_pem_write(context, _hx509_private_pem_name(key), NULL, sc->f,
505 			    data.data, data.length);
506 	    free(data.data);
507 	}
508 	break;
509     }
510 
511     return 0;
512 }
513 
514 static int
515 file_store(hx509_context context,
516 	   hx509_certs certs, void *data, int flags, hx509_lock lock)
517 {
518     struct ks_file *f = data;
519     struct store_ctx sc;
520     int ret;
521 
522     sc.f = fopen(f->fn, "w");
523     if (sc.f == NULL) {
524 	hx509_set_error_string(context, 0, ENOENT,
525 			       "Failed to open file %s for writing");
526 	return ENOENT;
527     }
528     sc.format = f->format;
529 
530     ret = hx509_certs_iter(context, f->certs, store_func, &sc);
531     fclose(sc.f);
532     return ret;
533 }
534 
535 static int
536 file_add(hx509_context context, hx509_certs certs, void *data, hx509_cert c)
537 {
538     struct ks_file *f = data;
539     return hx509_certs_add(context, f->certs, c);
540 }
541 
542 static int
543 file_iter_start(hx509_context context,
544 		hx509_certs certs, void *data, void **cursor)
545 {
546     struct ks_file *f = data;
547     return hx509_certs_start_seq(context, f->certs, cursor);
548 }
549 
550 static int
551 file_iter(hx509_context context,
552 	  hx509_certs certs, void *data, void *iter, hx509_cert *cert)
553 {
554     struct ks_file *f = data;
555     return hx509_certs_next_cert(context, f->certs, iter, cert);
556 }
557 
558 static int
559 file_iter_end(hx509_context context,
560 	      hx509_certs certs,
561 	      void *data,
562 	      void *cursor)
563 {
564     struct ks_file *f = data;
565     return hx509_certs_end_seq(context, f->certs, cursor);
566 }
567 
568 static int
569 file_getkeys(hx509_context context,
570 	     hx509_certs certs,
571 	     void *data,
572 	     hx509_private_key **keys)
573 {
574     struct ks_file *f = data;
575     return _hx509_certs_keys_get(context, f->certs, keys);
576 }
577 
578 static int
579 file_addkey(hx509_context context,
580 	     hx509_certs certs,
581 	     void *data,
582 	     hx509_private_key key)
583 {
584     struct ks_file *f = data;
585     return _hx509_certs_keys_add(context, f->certs, key);
586 }
587 
588 static struct hx509_keyset_ops keyset_file = {
589     "FILE",
590     0,
591     file_init_pem,
592     file_store,
593     file_free,
594     file_add,
595     NULL,
596     file_iter_start,
597     file_iter,
598     file_iter_end,
599     NULL,
600     file_getkeys,
601     file_addkey
602 };
603 
604 static struct hx509_keyset_ops keyset_pemfile = {
605     "PEM-FILE",
606     0,
607     file_init_pem,
608     file_store,
609     file_free,
610     file_add,
611     NULL,
612     file_iter_start,
613     file_iter,
614     file_iter_end,
615     NULL,
616     file_getkeys,
617     file_addkey
618 };
619 
620 static struct hx509_keyset_ops keyset_derfile = {
621     "DER-FILE",
622     0,
623     file_init_der,
624     file_store,
625     file_free,
626     file_add,
627     NULL,
628     file_iter_start,
629     file_iter,
630     file_iter_end,
631     NULL,
632     file_getkeys,
633     file_addkey
634 };
635 
636 
637 void
638 _hx509_ks_file_register(hx509_context context)
639 {
640     _hx509_ks_register(context, &keyset_file);
641     _hx509_ks_register(context, &keyset_pemfile);
642     _hx509_ks_register(context, &keyset_derfile);
643 }
644