1 /* Sign a module file using the given key.
3 * Copyright © 2014-2016 Red Hat, Inc. All Rights Reserved.
4 * Copyright © 2015 Intel Corporation.
5 * Copyright © 2016 Hewlett Packard Enterprise Development LP
7 * Authors: David Howells <dhowells@redhat.com>
8 * David Woodhouse <dwmw2@infradead.org>
9 * Juerg Haefliger <juerg.haefliger@hpe.com>
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.
24 #include <arpa/inet.h>
25 #include <openssl/opensslv.h>
26 #include <openssl/bio.h>
27 #include <openssl/evp.h>
28 #include <openssl/pem.h>
29 #include <openssl/err.h>
30 #include <openssl/engine.h>
33 * OpenSSL 3.0 deprecates the OpenSSL's ENGINE API.
35 * Remove this if/when that API is no longer used
37 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
40 * Use CMS if we have openssl-1.0.0 or newer available - otherwise we have to
41 * assume that it's not available and its header file is missing and that we
42 * should use PKCS#7 instead. Switching to the older PKCS#7 format restricts
43 * the options we have on specifying the X.509 certificate we want.
45 * Further, older versions of OpenSSL don't support manually adding signers to
46 * the PKCS#7 message so have to accept that we get a certificate included in
47 * the signature message. Nor do such older versions of OpenSSL support
48 * signing with anything other than SHA1 - so we're stuck with that if such is
51 #if defined(LIBRESSL_VERSION_NUMBER) || \
52 OPENSSL_VERSION_NUMBER < 0x10000000L || \
53 defined(OPENSSL_NO_CMS)
57 #include <openssl/cms.h>
59 #include <openssl/pkcs7.h>
62 struct module_signature
{
63 uint8_t algo
; /* Public-key crypto algorithm [0] */
64 uint8_t hash
; /* Digest algorithm [0] */
65 uint8_t id_type
; /* Key identifier type [PKEY_ID_PKCS7] */
66 uint8_t signer_len
; /* Length of signer's name [0] */
67 uint8_t key_id_len
; /* Length of key identifier [0] */
69 uint32_t sig_len
; /* Length of signature data */
72 #define PKEY_ID_PKCS7 2
74 static char magic_number
[] = "~Module signature appended~\n";
76 static __attribute__((noreturn
))
80 "Usage: scripts/sign-file [-dp] <hash algo> <key> <x509> <module> [<dest>]\n");
82 " scripts/sign-file -s <raw sig> <hash algo> <x509> <module> [<dest>]\n");
86 static void display_openssl_errors(int l
)
92 if (ERR_peek_error() == 0)
94 fprintf(stderr
, "At main.c:%d:\n", l
);
96 while ((e
= ERR_get_error_line(&file
, &line
))) {
97 ERR_error_string(e
, buf
);
98 fprintf(stderr
, "- SSL %s: %s:%d\n", buf
, file
, line
);
102 static void drain_openssl_errors(void)
107 if (ERR_peek_error() == 0)
109 while (ERR_get_error_line(&file
, &line
)) {}
112 #define ERR(cond, fmt, ...) \
114 bool __cond = (cond); \
115 display_openssl_errors(__LINE__); \
117 err(1, fmt, ## __VA_ARGS__); \
121 static const char *key_pass
;
123 static int pem_pw_cb(char *buf
, int len
, int w
, void *v
)
130 pwlen
= strlen(key_pass
);
134 strcpy(buf
, key_pass
);
136 /* If it's wrong, don't keep trying it. */
142 static EVP_PKEY
*read_private_key(const char *private_key_name
)
144 EVP_PKEY
*private_key
;
146 if (!strncmp(private_key_name
, "pkcs11:", 7)) {
149 ENGINE_load_builtin_engines();
150 drain_openssl_errors();
151 e
= ENGINE_by_id("pkcs11");
152 ERR(!e
, "Load PKCS#11 ENGINE");
154 drain_openssl_errors();
156 ERR(1, "ENGINE_init");
158 ERR(!ENGINE_ctrl_cmd_string(e
, "PIN", key_pass
, 0),
160 private_key
= ENGINE_load_private_key(e
, private_key_name
,
162 ERR(!private_key
, "%s", private_key_name
);
166 b
= BIO_new_file(private_key_name
, "rb");
167 ERR(!b
, "%s", private_key_name
);
168 private_key
= PEM_read_bio_PrivateKey(b
, NULL
, pem_pw_cb
,
170 ERR(!private_key
, "%s", private_key_name
);
177 static X509
*read_x509(const char *x509_name
)
179 unsigned char buf
[2];
184 b
= BIO_new_file(x509_name
, "rb");
185 ERR(!b
, "%s", x509_name
);
187 /* Look at the first two bytes of the file to determine the encoding */
188 n
= BIO_read(b
, buf
, 2);
190 if (BIO_should_retry(b
)) {
191 fprintf(stderr
, "%s: Read wanted retry\n", x509_name
);
195 fprintf(stderr
, "%s: Short read\n", x509_name
);
198 ERR(1, "%s", x509_name
);
201 ERR(BIO_reset(b
) != 0, "%s", x509_name
);
203 if (buf
[0] == 0x30 && buf
[1] >= 0x81 && buf
[1] <= 0x84)
204 /* Assume raw DER encoded X.509 */
205 x509
= d2i_X509_bio(b
, NULL
);
207 /* Assume PEM encoded X.509 */
208 x509
= PEM_read_bio_X509(b
, NULL
, NULL
, NULL
);
211 ERR(!x509
, "%s", x509_name
);
216 int main(int argc
, char **argv
)
218 struct module_signature sig_info
= { .id_type
= PKEY_ID_PKCS7
};
219 char *hash_algo
= NULL
;
220 char *private_key_name
= NULL
, *raw_sig_name
= NULL
;
221 char *x509_name
, *module_name
, *dest_name
;
222 bool save_sig
= false, replace_orig
;
223 bool sign_only
= false;
224 bool raw_sig
= false;
225 unsigned char buf
[4096];
226 unsigned long module_size
, sig_size
;
227 unsigned int use_signed_attrs
;
228 const EVP_MD
*digest_algo
;
229 EVP_PKEY
*private_key
;
231 CMS_ContentInfo
*cms
= NULL
;
232 unsigned int use_keyid
= 0;
239 OpenSSL_add_all_algorithms();
240 ERR_load_crypto_strings();
243 key_pass
= getenv("KBUILD_SIGN_PIN");
246 use_signed_attrs
= CMS_NOATTR
;
248 use_signed_attrs
= PKCS7_NOATTR
;
252 opt
= getopt(argc
, argv
, "sdpk");
254 case 's': raw_sig
= true; break;
255 case 'p': save_sig
= true; break;
256 case 'd': sign_only
= true; save_sig
= true; break;
258 case 'k': use_keyid
= CMS_USE_KEYID
; break;
267 if (argc
< 4 || argc
> 5)
271 raw_sig_name
= argv
[0];
275 private_key_name
= argv
[1];
278 module_name
= argv
[3];
279 if (argc
== 5 && strcmp(argv
[3], argv
[4]) != 0) {
281 replace_orig
= false;
283 ERR(asprintf(&dest_name
, "%s.~signed~", module_name
) < 0,
289 if (strcmp(hash_algo
, "sha1") != 0) {
290 fprintf(stderr
, "sign-file: %s only supports SHA1 signing\n",
291 OPENSSL_VERSION_TEXT
);
296 /* Open the module file */
297 bm
= BIO_new_file(module_name
, "rb");
298 ERR(!bm
, "%s", module_name
);
301 /* Read the private key and the X.509 cert the PKCS#7 message
304 private_key
= read_private_key(private_key_name
);
305 x509
= read_x509(x509_name
);
307 /* Digest the module data. */
308 OpenSSL_add_all_digests();
309 display_openssl_errors(__LINE__
);
310 digest_algo
= EVP_get_digestbyname(hash_algo
);
311 ERR(!digest_algo
, "EVP_get_digestbyname");
314 /* Load the signature message from the digest buffer. */
315 cms
= CMS_sign(NULL
, NULL
, NULL
, NULL
,
316 CMS_NOCERTS
| CMS_PARTIAL
| CMS_BINARY
|
317 CMS_DETACHED
| CMS_STREAM
);
318 ERR(!cms
, "CMS_sign");
320 ERR(!CMS_add1_signer(cms
, x509
, private_key
, digest_algo
,
321 CMS_NOCERTS
| CMS_BINARY
|
322 CMS_NOSMIMECAP
| use_keyid
|
325 ERR(CMS_final(cms
, bm
, NULL
, CMS_NOCERTS
| CMS_BINARY
) < 0,
329 pkcs7
= PKCS7_sign(x509
, private_key
, NULL
, bm
,
330 PKCS7_NOCERTS
| PKCS7_BINARY
|
331 PKCS7_DETACHED
| use_signed_attrs
);
332 ERR(!pkcs7
, "PKCS7_sign");
339 ERR(asprintf(&sig_file_name
, "%s.p7s", module_name
) < 0,
341 b
= BIO_new_file(sig_file_name
, "wb");
342 ERR(!b
, "%s", sig_file_name
);
344 ERR(i2d_CMS_bio_stream(b
, cms
, NULL
, 0) < 0,
345 "%s", sig_file_name
);
347 ERR(i2d_PKCS7_bio(b
, pkcs7
) < 0,
348 "%s", sig_file_name
);
359 /* Open the destination file now so that we can shovel the module data
360 * across as we read it.
362 bd
= BIO_new_file(dest_name
, "wb");
363 ERR(!bd
, "%s", dest_name
);
365 /* Append the marker and the PKCS#7 message to the destination file */
366 ERR(BIO_reset(bm
) < 0, "%s", module_name
);
367 while ((n
= BIO_read(bm
, buf
, sizeof(buf
))),
369 ERR(BIO_write(bd
, buf
, n
) < 0, "%s", dest_name
);
372 ERR(n
< 0, "%s", module_name
);
373 module_size
= BIO_number_written(bd
);
377 ERR(i2d_CMS_bio_stream(bd
, cms
, NULL
, 0) < 0, "%s", dest_name
);
379 ERR(i2d_PKCS7_bio(bd
, pkcs7
) < 0, "%s", dest_name
);
384 /* Read the raw signature file and write the data to the
387 b
= BIO_new_file(raw_sig_name
, "rb");
388 ERR(!b
, "%s", raw_sig_name
);
389 while ((n
= BIO_read(b
, buf
, sizeof(buf
))), n
> 0)
390 ERR(BIO_write(bd
, buf
, n
) < 0, "%s", dest_name
);
394 sig_size
= BIO_number_written(bd
) - module_size
;
395 sig_info
.sig_len
= htonl(sig_size
);
396 ERR(BIO_write(bd
, &sig_info
, sizeof(sig_info
)) < 0, "%s", dest_name
);
397 ERR(BIO_write(bd
, magic_number
, sizeof(magic_number
) - 1) < 0, "%s", dest_name
);
399 ERR(BIO_free(bd
) < 0, "%s", dest_name
);
401 /* Finally, if we're signing in place, replace the original. */
403 ERR(rename(dest_name
, module_name
) < 0, "%s", dest_name
);