1 /* Sign a module file using the given key.
2 *
3 * Copyright © 2014-2016 Red Hat, Inc. All Rights Reserved.
4 * Copyright © 2015 Intel Corporation.
5 * Copyright © 2016 Hewlett Packard Enterprise Development LP
6 *
7 * Authors: David Howells <dhowells@redhat.com>
8 * David Woodhouse <dwmw2@infradead.org>
9 * Juerg Haefliger <juerg.haefliger@hpe.com>
10 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU Lesser General Public License
13 * as published by the Free Software Foundation; either version 2.1
14 * of the licence, or (at your option) any later version.
15 */
16 #define _GNU_SOURCE
17 #include <stdio.h>
18 #include <stdlib.h>
19 #include <stdint.h>
20 #include <stdbool.h>
21 #include <string.h>
22 #include <getopt.h>
23 #include <err.h>
24 #include <arpa/inet.h>
25 #include <openssl/opensslv.h>
26 #include <openssl/bio.h>
27 #include <openssl/cms.h>
28 #include <openssl/evp.h>
29 #include <openssl/pem.h>
30 #include <openssl/err.h>
31 #if OPENSSL_VERSION_NUMBER >= 0x30000000L
32 # define USE_PKCS11_PROVIDER
33 # include <openssl/provider.h>
34 # include <openssl/store.h>
35 #else
36 # if !defined(OPENSSL_NO_ENGINE) && !defined(OPENSSL_NO_DEPRECATED_3_0)
37 # define USE_PKCS11_ENGINE
38 # include <openssl/engine.h>
39 # endif
40 #endif
41 #include "ssl-common.h"
42
43 struct module_signature {
44 uint8_t algo; /* Public-key crypto algorithm [0] */
45 uint8_t hash; /* Digest algorithm [0] */
46 uint8_t id_type; /* Key identifier type [PKEY_ID_PKCS7] */
47 uint8_t signer_len; /* Length of signer's name [0] */
48 uint8_t key_id_len; /* Length of key identifier [0] */
49 uint8_t __pad[3];
50 uint32_t sig_len; /* Length of signature data */
51 };
52
53 #define PKEY_ID_PKCS7 2
54
55 static char magic_number[] = "~Module signature appended~\n";
56
57 static __attribute__((noreturn))
format(void)58 void format(void)
59 {
60 fprintf(stderr,
61 "Usage: scripts/sign-file [-dp] <hash algo> <key> <x509> <module> [<dest>]\n");
62 fprintf(stderr,
63 " scripts/sign-file -s <raw sig> <hash algo> <x509> <module> [<dest>]\n");
64 exit(2);
65 }
66
67 static const char *key_pass;
68
pem_pw_cb(char * buf,int len,int w,void * v)69 static int pem_pw_cb(char *buf, int len, int w, void *v)
70 {
71 int pwlen;
72
73 if (!key_pass)
74 return -1;
75
76 pwlen = strlen(key_pass);
77 if (pwlen >= len)
78 return -1;
79
80 strcpy(buf, key_pass);
81
82 /* If it's wrong, don't keep trying it. */
83 key_pass = NULL;
84
85 return pwlen;
86 }
87
read_private_key_pkcs11(const char * private_key_name)88 static EVP_PKEY *read_private_key_pkcs11(const char *private_key_name)
89 {
90 EVP_PKEY *private_key = NULL;
91 #ifdef USE_PKCS11_PROVIDER
92 OSSL_STORE_CTX *store;
93
94 if (!OSSL_PROVIDER_try_load(NULL, "pkcs11", true))
95 ERR(1, "OSSL_PROVIDER_try_load(pkcs11)");
96 if (!OSSL_PROVIDER_try_load(NULL, "default", true))
97 ERR(1, "OSSL_PROVIDER_try_load(default)");
98
99 store = OSSL_STORE_open(private_key_name, NULL, NULL, NULL, NULL);
100 ERR(!store, "OSSL_STORE_open");
101
102 while (!OSSL_STORE_eof(store)) {
103 OSSL_STORE_INFO *info = OSSL_STORE_load(store);
104
105 if (!info) {
106 drain_openssl_errors(__LINE__, 0);
107 continue;
108 }
109 if (OSSL_STORE_INFO_get_type(info) == OSSL_STORE_INFO_PKEY) {
110 private_key = OSSL_STORE_INFO_get1_PKEY(info);
111 ERR(!private_key, "OSSL_STORE_INFO_get1_PKEY");
112 }
113 OSSL_STORE_INFO_free(info);
114 if (private_key)
115 break;
116 }
117 OSSL_STORE_close(store);
118 #elif defined(USE_PKCS11_ENGINE)
119 ENGINE *e;
120
121 ENGINE_load_builtin_engines();
122 drain_openssl_errors(__LINE__, 1);
123 e = ENGINE_by_id("pkcs11");
124 ERR(!e, "Load PKCS#11 ENGINE");
125 if (ENGINE_init(e))
126 drain_openssl_errors(__LINE__, 1);
127 else
128 ERR(1, "ENGINE_init");
129 if (key_pass)
130 ERR(!ENGINE_ctrl_cmd_string(e, "PIN", key_pass, 0), "Set PKCS#11 PIN");
131 private_key = ENGINE_load_private_key(e, private_key_name, NULL, NULL);
132 ERR(!private_key, "%s", private_key_name);
133 #else
134 fprintf(stderr, "no pkcs11 engine/provider available\n");
135 exit(1);
136 #endif
137 return private_key;
138 }
139
read_private_key(const char * private_key_name)140 static EVP_PKEY *read_private_key(const char *private_key_name)
141 {
142 if (!strncmp(private_key_name, "pkcs11:", 7)) {
143 return read_private_key_pkcs11(private_key_name);
144 } else {
145 EVP_PKEY *private_key;
146 BIO *b;
147
148 b = BIO_new_file(private_key_name, "rb");
149 ERR(!b, "%s", private_key_name);
150 private_key = PEM_read_bio_PrivateKey(b, NULL, pem_pw_cb,
151 NULL);
152 ERR(!private_key, "%s", private_key_name);
153 BIO_free(b);
154
155 return private_key;
156 }
157 }
158
read_x509(const char * x509_name)159 static X509 *read_x509(const char *x509_name)
160 {
161 unsigned char buf[2];
162 X509 *x509;
163 BIO *b;
164 int n;
165
166 b = BIO_new_file(x509_name, "rb");
167 ERR(!b, "%s", x509_name);
168
169 /* Look at the first two bytes of the file to determine the encoding */
170 n = BIO_read(b, buf, 2);
171 if (n != 2) {
172 if (BIO_should_retry(b)) {
173 fprintf(stderr, "%s: Read wanted retry\n", x509_name);
174 exit(1);
175 }
176 if (n >= 0) {
177 fprintf(stderr, "%s: Short read\n", x509_name);
178 exit(1);
179 }
180 ERR(1, "%s", x509_name);
181 }
182
183 ERR(BIO_reset(b) != 0, "%s", x509_name);
184
185 if (buf[0] == 0x30 && buf[1] >= 0x81 && buf[1] <= 0x84)
186 /* Assume raw DER encoded X.509 */
187 x509 = d2i_X509_bio(b, NULL);
188 else
189 /* Assume PEM encoded X.509 */
190 x509 = PEM_read_bio_X509(b, NULL, NULL, NULL);
191
192 BIO_free(b);
193 ERR(!x509, "%s", x509_name);
194
195 return x509;
196 }
197
main(int argc,char ** argv)198 int main(int argc, char **argv)
199 {
200 struct module_signature sig_info = { .id_type = PKEY_ID_PKCS7 };
201 char *hash_algo = NULL;
202 char *private_key_name = NULL, *raw_sig_name = NULL;
203 char *x509_name, *module_name, *dest_name;
204 bool save_sig = false, replace_orig;
205 bool sign_only = false;
206 bool raw_sig = false;
207 unsigned char buf[4096];
208 unsigned long module_size, sig_size;
209 const EVP_MD *digest_algo;
210 EVP_PKEY *private_key;
211 CMS_ContentInfo *cms = NULL;
212 unsigned int use_keyid = 0;
213 X509 *x509;
214 BIO *bd, *bm;
215 int opt, n;
216 OpenSSL_add_all_algorithms();
217 ERR_load_crypto_strings();
218 ERR_clear_error();
219
220 key_pass = getenv("KBUILD_SIGN_PIN");
221
222 do {
223 opt = getopt(argc, argv, "sdpk");
224 switch (opt) {
225 case 's': raw_sig = true; break;
226 case 'p': save_sig = true; break;
227 case 'd': sign_only = true; save_sig = true; break;
228 case 'k': use_keyid = CMS_USE_KEYID; break;
229 case -1: break;
230 default: format();
231 }
232 } while (opt != -1);
233
234 argc -= optind;
235 argv += optind;
236 if (argc < 4 || argc > 5)
237 format();
238
239 if (raw_sig) {
240 raw_sig_name = argv[0];
241 hash_algo = argv[1];
242 } else {
243 hash_algo = argv[0];
244 private_key_name = argv[1];
245 }
246 x509_name = argv[2];
247 module_name = argv[3];
248 if (argc == 5 && strcmp(argv[3], argv[4]) != 0) {
249 dest_name = argv[4];
250 replace_orig = false;
251 } else {
252 ERR(asprintf(&dest_name, "%s.~signed~", module_name) < 0,
253 "asprintf");
254 replace_orig = true;
255 }
256
257 /* Open the module file */
258 bm = BIO_new_file(module_name, "rb");
259 ERR(!bm, "%s", module_name);
260
261 if (!raw_sig) {
262 /* Read the private key and the X.509 cert the PKCS#7 message
263 * will point to.
264 */
265 private_key = read_private_key(private_key_name);
266 x509 = read_x509(x509_name);
267
268 /* Digest the module data. */
269 OpenSSL_add_all_digests();
270 drain_openssl_errors(__LINE__, 0);
271 digest_algo = EVP_get_digestbyname(hash_algo);
272 ERR(!digest_algo, "EVP_get_digestbyname");
273
274 unsigned int flags =
275 CMS_NOCERTS |
276 CMS_NOATTR |
277 CMS_PARTIAL |
278 CMS_BINARY |
279 CMS_DETACHED |
280 CMS_STREAM |
281 CMS_NOSMIMECAP |
282 #ifdef CMS_NO_SIGNING_TIME
283 CMS_NO_SIGNING_TIME |
284 #endif
285 use_keyid;
286
287 #if OPENSSL_VERSION_NUMBER >= 0x30000000L && OPENSSL_VERSION_NUMBER < 0x40000000L
288 if (EVP_PKEY_is_a(private_key, "ML-DSA-44") ||
289 EVP_PKEY_is_a(private_key, "ML-DSA-65") ||
290 EVP_PKEY_is_a(private_key, "ML-DSA-87")) {
291 /* ML-DSA + CMS_NOATTR is not supported in openssl-3.5
292 * and before.
293 */
294 flags &= ~CMS_NOATTR;
295 }
296 #endif
297
298 /* Load the signature message from the digest buffer. */
299 cms = CMS_sign(NULL, NULL, NULL, NULL, flags);
300 ERR(!cms, "CMS_sign");
301
302 ERR(!CMS_add1_signer(cms, x509, private_key, digest_algo, flags),
303 "CMS_add1_signer");
304 ERR(CMS_final(cms, bm, NULL, flags) != 1,
305 "CMS_final");
306
307 if (save_sig) {
308 char *sig_file_name;
309 BIO *b;
310
311 ERR(asprintf(&sig_file_name, "%s.p7s", module_name) < 0,
312 "asprintf");
313 b = BIO_new_file(sig_file_name, "wb");
314 ERR(!b, "%s", sig_file_name);
315 ERR(i2d_CMS_bio_stream(b, cms, NULL, 0) != 1,
316 "%s", sig_file_name);
317 BIO_free(b);
318 }
319
320 if (sign_only) {
321 BIO_free(bm);
322 return 0;
323 }
324 }
325
326 /* Open the destination file now so that we can shovel the module data
327 * across as we read it.
328 */
329 bd = BIO_new_file(dest_name, "wb");
330 ERR(!bd, "%s", dest_name);
331
332 /* Append the marker and the PKCS#7 message to the destination file */
333 ERR(BIO_reset(bm) < 0, "%s", module_name);
334 while ((n = BIO_read(bm, buf, sizeof(buf))),
335 n > 0) {
336 ERR(BIO_write(bd, buf, n) < 0, "%s", dest_name);
337 }
338 BIO_free(bm);
339 ERR(n < 0, "%s", module_name);
340 module_size = BIO_number_written(bd);
341
342 if (!raw_sig) {
343 ERR(i2d_CMS_bio_stream(bd, cms, NULL, 0) != 1, "%s", dest_name);
344 } else {
345 BIO *b;
346
347 /* Read the raw signature file and write the data to the
348 * destination file
349 */
350 b = BIO_new_file(raw_sig_name, "rb");
351 ERR(!b, "%s", raw_sig_name);
352 while ((n = BIO_read(b, buf, sizeof(buf))), n > 0)
353 ERR(BIO_write(bd, buf, n) < 0, "%s", dest_name);
354 BIO_free(b);
355 }
356
357 sig_size = BIO_number_written(bd) - module_size;
358 sig_info.sig_len = htonl(sig_size);
359 ERR(BIO_write(bd, &sig_info, sizeof(sig_info)) < 0, "%s", dest_name);
360 ERR(BIO_write(bd, magic_number, sizeof(magic_number) - 1) < 0, "%s", dest_name);
361
362 ERR(BIO_free(bd) != 1, "%s", dest_name);
363
364 /* Finally, if we're signing in place, replace the original. */
365 if (replace_orig)
366 ERR(rename(dest_name, module_name) < 0, "%s", dest_name);
367
368 return 0;
369 }
370