xref: /netbsd-src/usr.bin/nbsvtool/nbsvtool.c (revision f82d7874c259b2a6cc59b714f844919f32bf7b51)
1 /*	$NetBSD: nbsvtool.c,v 1.1 2008/05/11 17:58:09 joerg Exp $	*/
2 
3 /*-
4  * Copyright (c) 2004, 2008 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Love H�rnquist �strand <lha@it.su.se>
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
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  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <err.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include <unistd.h>
37 
38 #include <openssl/pkcs7.h>
39 #include <openssl/evp.h>
40 #include <openssl/x509.h>
41 #include <openssl/x509v3.h>
42 #include <openssl/pem.h>
43 #include <openssl/err.h>
44 #include <openssl/ui.h>
45 
46 static int verbose_flag;
47 static unsigned long key_usage = 0;
48 
49 /*
50  * openssl command line equivalents
51  *
52  *    openssl smime -verify \
53  *		-inform PEM -in nbsvtool.c.sig -content nbsvtool.c \
54  *		-CAfile /secure/lha/su/CA/swupki-pca.crt -out /dev/null
55  *    openssl smime -sign \
56  *		-noattr -binary -outform PEM -out nbsvtool.c.sig \
57  *		-in nbsvtool.c -signer /secure/lha/su/CA/lha.crt \
58  *		-certfile /secure/lha/su/CA/lha-chain \
59  *		-inkey /secure/lha/su/CA/lha.key
60  */
61 
62 /*
63  * Create a detach PEM signature of file `infile' and store it in
64  * `outfile'. The signer certificate `cert' and private key
65  * `private_key' must be given. An additional hint to the verifier how
66  * to find the path from the `cert' to the x509 anchor can be passed
67  * in `cert_chain'.
68  */
69 
70 static void
71 sign_file(X509 *cert, EVP_PKEY *private_key, STACK_OF(X509) *cert_chain,
72 	  const char *infile, const char *outfile)
73 {
74 	BIO *out, *in;
75 	PKCS7 *p7;
76 
77 	out = BIO_new_file(outfile, "w");
78 	if (out == NULL)
79 		err(EXIT_FAILURE, "Failed to open signature output file: %s",
80 		    outfile);
81 
82 	in = BIO_new_file(infile, "r");
83 	if (in == NULL)
84 		err(EXIT_FAILURE, "Failed to input file: %s", infile);
85 
86 	p7 = PKCS7_sign(cert, private_key, cert_chain, in,
87 	    PKCS7_DETACHED|PKCS7_NOATTR|PKCS7_BINARY);
88 	if (p7 == NULL)
89 		errx(EXIT_FAILURE, "Failed to create signature structure");
90 
91 	PEM_write_bio_PKCS7(out, p7);
92 
93 	PKCS7_free(p7);
94 	BIO_free(in);
95 	BIO_free_all(out);
96 }
97 
98 /*
99  * Verifies a detached PEM signature in the file `sigfile' of file
100  * `infile'. The trust anchor file `anchor' to the trust anchors must
101  * be given. If its suspended that the sender didn't inlude the whole
102  * path from the signing certificate to the given trust anchor, extra
103  * certificates can be passed in `cert_chain'.
104  */
105 
106 static void
107 verify_file(STACK_OF(X509) *cert_chain, const char *anchor,
108 	    const char *infile, const char *sigfile)
109 {
110 	STACK_OF(X509) *signers;
111 	X509_STORE *store;
112 	BIO *sig, *in;
113 	PKCS7 *p7;
114 	int ret, i;
115 
116 	store = X509_STORE_new();
117 	if (store == NULL)
118 		err(1, "Failed to create store");
119 
120 	X509_STORE_load_locations(store, anchor, NULL);
121 
122 	in = BIO_new_file(infile, "r");
123 	if (in == NULL)
124 		err(EXIT_FAILURE, "Failed to open input data file: %s", infile);
125 
126 	sig = BIO_new_file(sigfile, "r");
127 	if (sig == NULL)
128 		err(EXIT_FAILURE, "Failed to open signature input file: %s",
129 		    sigfile);
130 
131 	p7 = PEM_read_bio_PKCS7(sig, NULL, NULL, NULL);
132 	if (p7 == NULL)
133 		errx(EXIT_FAILURE, "Failed to parse the signature file %s",
134 		    sigfile);
135 
136 	ret = PKCS7_verify(p7, cert_chain, store, in, NULL, 0);
137 	if (ret != 1)
138 		errx(EXIT_FAILURE, "Failed to verify signature");
139 
140 	signers = PKCS7_get0_signers(p7, NULL, 0);
141 	if (signers == NULL)
142 		errx(EXIT_FAILURE, "Failed to get signers");
143 
144 	if (sk_X509_num(signers) == 0)
145 		errx(EXIT_FAILURE, "No signers ?");
146 
147 	if (verbose_flag)
148 		printf("Sigature ok, signed by:\n");
149 
150 	for (i = 0; i < sk_X509_num(signers); i++) {
151 		X509_NAME *name;
152 		char *subject;
153 		name = X509_get_subject_name(sk_X509_value(signers, i));
154 		subject = X509_NAME_oneline(name, NULL, 0);
155 
156 		if (key_usage != 0 &&
157 		    (sk_X509_value(signers, i)->ex_xkusage & key_usage) == 0)
158 			errx(EXIT_FAILURE,
159 			    "Key doesn't match required key usage: %s",
160 			    subject);
161 
162 		if (verbose_flag)
163 			printf("\t%s\n", subject);
164 
165 		OPENSSL_free(subject);
166 	}
167 
168 	PKCS7_free(p7);
169 	BIO_free(in);
170 	BIO_free(sig);
171 }
172 
173 /*
174  * Parse and return a list PEM encoded certificates in the file
175  * `file'. In case of error or an empty file, and error text will be
176  * printed and the function will exit(3).
177  */
178 
179 static STACK_OF(X509) *
180 file_to_certs(const char *file)
181 {
182 	STACK_OF(X509) *certs;
183 	FILE *f;
184 
185 	f = fopen(file, "r");
186 	if (f == NULL)
187 		err(EXIT_FAILURE, "Cannot open certificate file %s", file);
188 	certs = sk_X509_new_null();
189 	while (1) {
190 		X509 *cert;
191 
192 		cert = PEM_read_X509(f, NULL, NULL, NULL);
193 		if (cert == NULL) {
194 			unsigned long ret;
195 
196 			ret = ERR_GET_REASON(ERR_peek_error());
197 			if (ret == PEM_R_NO_START_LINE) {
198 				/* End of file reached. no error */
199 				ERR_clear_error();
200 				break;
201 			}
202 			errx(EXIT_FAILURE, "Can't read certificate file %s",
203 			    file);
204 		}
205 		sk_X509_insert(certs, cert, sk_X509_num(certs));
206 	}
207 	fclose(f);
208 	if (sk_X509_num(certs) == 0)
209 		errx(EXIT_FAILURE, "No certificate found file %s", file);
210 
211 	return certs;
212 }
213 
214 static int
215 ssl_pass_cb(char *buf, int size, int rwflag, void *u)
216 {
217 
218 	if (UI_UTIL_read_pw_string(buf, size, "Passphrase: ", 0))
219 		return 0;
220 	return strlen(buf);
221 }
222 
223 static struct {
224 	X509 *certificate;
225 	STACK_OF(X509) *cert_chain;
226 	EVP_PKEY *private_key;
227 } crypto_state;
228 
229 /*
230  * Load the certificate file `cert_file' with the associated private
231  * key file `key_file'. The private key is checked to make sure it
232  * matches the certificate. The optional hints for the path to the CA
233  * is stored in `chain_file'.
234  */
235 
236 static void
237 load_keys(const char *cert_file, const char *chain_file, const char *key_file)
238 {
239 	STACK_OF(X509) *c;
240 	FILE *f;
241 	int ret;
242 
243 	if (cert_file == NULL)
244 		errx(EXIT_FAILURE, "No certificate file given");
245 	if (key_file == NULL)
246 		errx(EXIT_FAILURE, "No private key file given");
247 
248 	c = file_to_certs(cert_file);
249 
250 	if (sk_X509_num(c) != 1)
251 		errx(EXIT_FAILURE,
252 		    "More then one certificate in the certificate file");
253 	crypto_state.certificate = sk_X509_value(c, 0);
254 
255 	if (chain_file)
256 		crypto_state.cert_chain = file_to_certs(chain_file);
257 
258 	/* load private key */
259 	f = fopen(key_file, "r");
260 	if (f == NULL)
261 		errx(1, "Failed to open private key file %s", key_file);
262 
263 	crypto_state.private_key =
264 		PEM_read_PrivateKey(f, NULL, ssl_pass_cb, NULL);
265 	fclose(f);
266 	if (crypto_state.private_key == NULL)
267 		errx(EXIT_FAILURE, "Can't read private key %s", key_file);
268 
269 	ret = X509_check_private_key(crypto_state.certificate,
270 	    crypto_state.private_key);
271 	if (ret != 1)
272 		errx(EXIT_FAILURE,
273 		    "The private key %s doesn't match the certificate %s",
274 		    key_file, cert_file);
275 }
276 
277 static void __dead
278 usage(int exit_code)
279 {
280 
281 	printf("%s usage\n", getprogname());
282 	printf("%s -k keyfile -c cert-chain [-f cert-chain] sign file\n",
283 	    getprogname());
284 	printf("%s [-u code|...] [-a x509-anchor-file] verify filename.sp7\n",
285 	    getprogname());
286 	printf("%s [-u code|...] [-a x509-anchor-file] verify filename otherfilename.sp7\n",
287 	    getprogname());
288 	printf("%s [-u code|...] [-a x509-anchor-file] verify-code file ...\n",
289 	    getprogname());
290 	exit(exit_code);
291 }
292 
293 int
294 main(int argc, char **argv)
295 {
296 	const char *anchors = NULL;
297 	const char *cert_file = NULL, *key_file = NULL, *chain_file = NULL;
298 	const char *file;
299 	char *sigfile;
300 	int ch;
301 
302 	setprogname(argv[0]);
303 
304 	OpenSSL_add_all_algorithms();
305 	ERR_load_crypto_strings();
306 
307 	while ((ch = getopt(argc, argv, "a:c:f:hk:u:v")) != -1) {
308 		switch (ch) {
309 		case 'a':
310 			anchors = optarg;
311 			break;
312 		case 'f':
313 			chain_file = optarg;
314 			break;
315 		case 'k':
316 			key_file = optarg;
317 			break;
318 		case 'c':
319 			cert_file = optarg;
320 			break;
321 		case 'u':
322 			if (strcmp("ssl-server", optarg) == 0)
323 				key_usage |= XKU_SSL_SERVER;
324 			else if (strcmp("ssl-client", optarg) == 0)
325 				key_usage |= XKU_SSL_CLIENT;
326 			else if (strcmp("code", optarg) == 0)
327 				key_usage |= XKU_CODE_SIGN;
328 			else if (strcmp("smime", optarg) == 0)
329 				key_usage |= XKU_SMIME;
330 			else
331 				errx(1, "Unknown keyusage: %s", optarg);
332 			break;
333 		case 'v':
334 			verbose_flag = 1;
335 			break;
336 		case 'h':
337 			usage(EXIT_SUCCESS);
338 		default:
339 			usage(EXIT_FAILURE);
340 		}
341 	}
342 
343 	argc -= optind;
344 	argv += optind;
345 
346 	if (argc < 1) {
347 		fprintf(stderr, "Command missing [sign|verify]\n");
348 		usage(EXIT_FAILURE);
349 	}
350 
351 	if (strcmp(argv[0], "sign") == 0) {
352 
353 		if (argc < 2)
354 			usage(1);
355 
356 		file = argv[1];
357 
358 		asprintf(&sigfile, "%s.sp7", file);
359 		if (sigfile == NULL)
360 			err(EXIT_FAILURE, "asprintf failed");
361 
362 		load_keys(cert_file, chain_file, key_file);
363 
364 		sign_file(crypto_state.certificate,
365 		    crypto_state.private_key,
366 		    crypto_state.cert_chain,
367 		    file,
368 		    sigfile);
369 
370 	} else if (strcmp(argv[0], "verify") == 0
371 	    || strcmp(argv[0], "verify-code") == 0) {
372 
373 		if (strcmp(argv[0], "verify-code") == 0)
374 			key_usage |= XKU_CODE_SIGN;
375 
376 		if (argc < 2)
377 			usage(1);
378 		else if (argc < 3) {
379 			char *dot;
380 
381 			sigfile = argv[1];
382 
383 			file = strdup(sigfile);
384 			if (file == NULL)
385 				err(1, "strdup failed");
386 
387 			dot = strrchr(file, '.');
388 			if (dot == NULL || strchr(dot, '/') != NULL)
389 				errx(EXIT_FAILURE,
390 				    "File name missing suffix");
391 			if (strcmp(".sp7", dot) != 0)
392 				errx(EXIT_FAILURE,
393 				    "File name bad suffix (%s)", dot);
394 			*dot = '\0';
395 		} else {
396 			file = argv[1];
397 			sigfile = argv[2];
398 		}
399 		verify_file(crypto_state.cert_chain, anchors, file, sigfile);
400 	} else {
401 		fprintf(stderr, "Unknown command: %s\n", argv[0]);
402 		usage(EXIT_FAILURE);
403 	}
404 
405 	return 0;
406 }
407