[mirror_ubuntu-bionic-kernel.git] / scripts / sign-file.c

/* Sign a module file using the given key.
 *
 * Copyright (C) 2014 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public Licence
 * as published by the Free Software Foundation; either version
 * 2 of the Licence, or (at your option) any later version.
 */
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdbool.h>
#include <string.h>
#include <getopt.h>
#include <err.h>
#include <arpa/inet.h>
#include <openssl/bio.h>
#include <openssl/evp.h>
#include <openssl/pem.h>
#include <openssl/cms.h>
#include <openssl/err.h>
#include <openssl/engine.h>

struct module_signature {
	uint8_t		algo;		/* Public-key crypto algorithm [0] */
	uint8_t		hash;		/* Digest algorithm [0] */
	uint8_t		id_type;	/* Key identifier type [PKEY_ID_PKCS7] */
	uint8_t		signer_len;	/* Length of signer's name [0] */
	uint8_t		key_id_len;	/* Length of key identifier [0] */
	uint8_t		__pad[3];
	uint32_t	sig_len;	/* Length of signature data */
};

#define PKEY_ID_PKCS7 2

static char magic_number[] = "~Module signature appended~\n";

static __attribute__((noreturn))
void format(void)
{
	fprintf(stderr,
		"Usage: scripts/sign-file [-dp] <hash algo> <key> <x509> <module> [<dest>]\n");
	exit(2);
}

static void display_openssl_errors(int l)
{
	const char *file;
	char buf[120];
	int e, line;

	if (ERR_peek_error() == 0)
		return;
	fprintf(stderr, "At main.c:%d:\n", l);

	while ((e = ERR_get_error_line(&file, &line))) {
		ERR_error_string(e, buf);
		fprintf(stderr, "- SSL %s: %s:%d\n", buf, file, line);
	}
}

static void drain_openssl_errors(void)
{
	const char *file;
	int line;

	if (ERR_peek_error() == 0)
		return;
	while (ERR_get_error_line(&file, &line)) {}
}

#define ERR(cond, fmt, ...)				\
	do {						\
		bool __cond = (cond);			\
		display_openssl_errors(__LINE__);	\
		if (__cond) {				\
			err(1, fmt, ## __VA_ARGS__);	\
		}					\
	} while(0)

static const char *key_pass;

static int pem_pw_cb(char *buf, int len, int w, void *v)
{
	int pwlen;

	if (!key_pass)
		return -1;

	pwlen = strlen(key_pass);
	if (pwlen >= len)
		return -1;

	strcpy(buf, key_pass);

	/* If it's wrong, don't keep trying it. */
	key_pass = NULL;

	return pwlen;
}

int main(int argc, char **argv)
{
	struct module_signature sig_info = { .id_type = PKEY_ID_PKCS7 };
	char *hash_algo = NULL;
	char *private_key_name, *x509_name, *module_name, *dest_name;
	bool save_cms = false, replace_orig;
	bool sign_only = false;
	unsigned char buf[4096];
	unsigned long module_size, cms_size;
	unsigned int use_keyid = 0, use_signed_attrs = CMS_NOATTR;
	const EVP_MD *digest_algo;
	EVP_PKEY *private_key;
	CMS_ContentInfo *cms;
	X509 *x509;
	BIO *b, *bd = NULL, *bm;
	int opt, n;

	OpenSSL_add_all_algorithms();
	ERR_load_crypto_strings();
	ERR_clear_error();

	key_pass = getenv("KBUILD_SIGN_PIN");

	do {
		opt = getopt(argc, argv, "dpk");
		switch (opt) {
		case 'p': save_cms = true; break;
		case 'd': sign_only = true; save_cms = true; break;
		case 'k': use_keyid = CMS_USE_KEYID; break;
		case -1: break;
		default: format();
		}
	} while (opt != -1);

	argc -= optind;
	argv += optind;
	if (argc < 4 || argc > 5)
		format();

	hash_algo = argv[0];
	private_key_name = argv[1];
	x509_name = argv[2];
	module_name = argv[3];
	if (argc == 5) {
		dest_name = argv[4];
		replace_orig = false;
	} else {
		ERR(asprintf(&dest_name, "%s.~signed~", module_name) < 0,
		    "asprintf");
		replace_orig = true;
	}

	/* Read the private key and the X.509 cert the PKCS#7 message
	 * will point to.
	 */
	if (!strncmp(private_key_name, "pkcs11:", 7)) {
		ENGINE *e;

		ENGINE_load_builtin_engines();
		drain_openssl_errors();
		e = ENGINE_by_id("pkcs11");
		ERR(!e, "Load PKCS#11 ENGINE");
		if (ENGINE_init(e))
			drain_openssl_errors();
		else
			ERR(1, "ENGINE_init");
		if (key_pass)
			ERR(!ENGINE_ctrl_cmd_string(e, "PIN", key_pass, 0), "Set PKCS#11 PIN");
		private_key = ENGINE_load_private_key(e, private_key_name, NULL,
						      NULL);
		ERR(!private_key, "%s", private_key_name);
	} else {
		b = BIO_new_file(private_key_name, "rb");
		ERR(!b, "%s", private_key_name);
		private_key = PEM_read_bio_PrivateKey(b, NULL, pem_pw_cb, NULL);
		ERR(!private_key, "%s", private_key_name);
		BIO_free(b);
	}

	b = BIO_new_file(x509_name, "rb");
	ERR(!b, "%s", x509_name);
	x509 = d2i_X509_bio(b, NULL); /* Binary encoded X.509 */
	if (!x509) {
		ERR(BIO_reset(b) != 1, "%s", x509_name);
		x509 = PEM_read_bio_X509(b, NULL, NULL, NULL); /* PEM encoded X.509 */
		if (x509)
			drain_openssl_errors();
	}
	BIO_free(b);
	ERR(!x509, "%s", x509_name);

	/* Open the destination file now so that we can shovel the module data
	 * across as we read it.
	 */
	if (!sign_only) {
		bd = BIO_new_file(dest_name, "wb");
		ERR(!bd, "%s", dest_name);
	}

	/* Digest the module data. */
	OpenSSL_add_all_digests();
	display_openssl_errors(__LINE__);
	digest_algo = EVP_get_digestbyname(hash_algo);
	ERR(!digest_algo, "EVP_get_digestbyname");

	bm = BIO_new_file(module_name, "rb");
	ERR(!bm, "%s", module_name);

	/* Load the CMS message from the digest buffer. */
	cms = CMS_sign(NULL, NULL, NULL, NULL,
		       CMS_NOCERTS | CMS_PARTIAL | CMS_BINARY | CMS_DETACHED | CMS_STREAM);
	ERR(!cms, "CMS_sign");

	ERR(!CMS_add1_signer(cms, x509, private_key, digest_algo,
			     CMS_NOCERTS | CMS_BINARY | CMS_NOSMIMECAP |
			     use_keyid | use_signed_attrs),
	    "CMS_sign_add_signer");
	ERR(CMS_final(cms, bm, NULL, CMS_NOCERTS | CMS_BINARY) < 0,
	    "CMS_final");

	if (save_cms) {
		char *cms_name;

		ERR(asprintf(&cms_name, "%s.p7s", module_name) < 0, "asprintf");
		b = BIO_new_file(cms_name, "wb");
		ERR(!b, "%s", cms_name);
		ERR(i2d_CMS_bio_stream(b, cms, NULL, 0) < 0, "%s", cms_name);
		BIO_free(b);
	}

	if (sign_only)
		return 0;

	/* Append the marker and the PKCS#7 message to the destination file */
	ERR(BIO_reset(bm) < 0, "%s", module_name);
	while ((n = BIO_read(bm, buf, sizeof(buf))),
	       n > 0) {
		ERR(BIO_write(bd, buf, n) < 0, "%s", dest_name);
	}
	ERR(n < 0, "%s", module_name);
	module_size = BIO_number_written(bd);

	ERR(i2d_CMS_bio_stream(bd, cms, NULL, 0) < 0, "%s", dest_name);
	cms_size = BIO_number_written(bd) - module_size;
	sig_info.sig_len = htonl(cms_size);
	ERR(BIO_write(bd, &sig_info, sizeof(sig_info)) < 0, "%s", dest_name);
	ERR(BIO_write(bd, magic_number, sizeof(magic_number) - 1) < 0, "%s", dest_name);

	ERR(BIO_free(bd) < 0, "%s", dest_name);

	/* Finally, if we're signing in place, replace the original. */
	if (replace_orig)
		ERR(rename(dest_name, module_name) < 0, "%s", dest_name);

	return 0;
}
Commit	Line	Data
bc1c373d DH	1	/* Sign a module file using the given key.
	2	*
	3	* Copyright (C) 2014 Red Hat, Inc. All Rights Reserved.
	4	* Written by David Howells (dhowells@redhat.com)
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public Licence
	8	* as published by the Free Software Foundation; either version
	9	* 2 of the Licence, or (at your option) any later version.
	10	*/
	11	#define _GNU_SOURCE
	12	#include <stdio.h>
	13	#include <stdlib.h>
	14	#include <stdint.h>
	15	#include <stdbool.h>
	16	#include <string.h>
	17	#include <getopt.h>
	18	#include <err.h>
	19	#include <arpa/inet.h>
	20	#include <openssl/bio.h>
	21	#include <openssl/evp.h>
	22	#include <openssl/pem.h>
ed8c2076	23	#include <openssl/cms.h>
bc1c373d	24	#include <openssl/err.h>
6e3e281f	25	#include <openssl/engine.h>
bc1c373d DH	26
	27	struct module_signature {
	28	uint8_t algo; /* Public-key crypto algorithm [0] */
	29	uint8_t hash; /* Digest algorithm [0] */
	30	uint8_t id_type; /* Key identifier type [PKEY_ID_PKCS7] */
	31	uint8_t signer_len; /* Length of signer's name [0] */
	32	uint8_t key_id_len; /* Length of key identifier [0] */
	33	uint8_t __pad[3];
	34	uint32_t sig_len; /* Length of signature data */
	35	};
	36
	37	#define PKEY_ID_PKCS7 2
	38
	39	static char magic_number[] = "~Module signature appended~\n";
	40
	41	static __attribute__((noreturn))
	42	void format(void)
	43	{
	44	fprintf(stderr,
	45	"Usage: scripts/sign-file [-dp] <hash algo> <key> <x509> <module> [<dest>]\n");
	46	exit(2);
	47	}
	48
	49	static void display_openssl_errors(int l)
	50	{
	51	const char *file;
	52	char buf[120];
	53	int e, line;
	54
	55	if (ERR_peek_error() == 0)
	56	return;
	57	fprintf(stderr, "At main.c:%d:\n", l);
	58
	59	while ((e = ERR_get_error_line(&file, &line))) {
	60	ERR_error_string(e, buf);
	61	fprintf(stderr, "- SSL %s: %s:%d\n", buf, file, line);
	62	}
	63	}
	64
	65	static void drain_openssl_errors(void)
	66	{
	67	const char *file;
	68	int line;
	69
	70	if (ERR_peek_error() == 0)
	71	return;
	72	while (ERR_get_error_line(&file, &line)) {}
	73	}
	74
	75	#define ERR(cond, fmt, ...) \
	76	do { \
	77	bool __cond = (cond); \
	78	display_openssl_errors(__LINE__); \
	79	if (__cond) { \
	80	err(1, fmt, ## __VA_ARGS__); \
	81	} \
	82	} while(0)
	83
af1eb291 DW	84	static const char *key_pass;
	85
	86	static int pem_pw_cb(char buf, int len, int w, void v)
	87	{
	88	int pwlen;
	89
	90	if (!key_pass)
	91	return -1;
	92
	93	pwlen = strlen(key_pass);
	94	if (pwlen >= len)
	95	return -1;
	96
	97	strcpy(buf, key_pass);
	98
	99	/* If it's wrong, don't keep trying it. */
	100	key_pass = NULL;
	101
	102	return pwlen;
	103	}
	104
bc1c373d DH	105	int main(int argc, char **argv)
	106	{
	107	struct module_signature sig_info = { .id_type = PKEY_ID_PKCS7 };
	108	char *hash_algo = NULL;
	109	char private_key_name, x509_name, module_name, dest_name;
ed8c2076	110	bool save_cms = false, replace_orig;
23dfbbab	111	bool sign_only = false;
bc1c373d	112	unsigned char buf[4096];
ed8c2076	113	unsigned long module_size, cms_size;
99db4435	114	unsigned int use_keyid = 0, use_signed_attrs = CMS_NOATTR;
bc1c373d DH	115	const EVP_MD *digest_algo;
bc1c373d DH	116	EVP_PKEY *private_key;
ed8c2076	117	CMS_ContentInfo *cms;
bc1c373d	118	X509 *x509;
23dfbbab	119	BIO b, bd = NULL, *bm;
bc1c373d DH	120	int opt, n;
bc1c373d DH	121
af1eb291	122	OpenSSL_add_all_algorithms();
bc1c373d DH	123	ERR_load_crypto_strings();
	124	ERR_clear_error();
	125
af1eb291 DW	126	key_pass = getenv("KBUILD_SIGN_PIN");
af1eb291 DW	127
bc1c373d	128	do {
ed8c2076	129	opt = getopt(argc, argv, "dpk");
bc1c373d	130	switch (opt) {
ed8c2076 DH	131	case 'p': save_cms = true; break;
	132	case 'd': sign_only = true; save_cms = true; break;
	133	case 'k': use_keyid = CMS_USE_KEYID; break;
bc1c373d DH	134	case -1: break;
	135	default: format();
	136	}
	137	} while (opt != -1);
	138
	139	argc -= optind;
	140	argv += optind;
	141	if (argc < 4 \|\| argc > 5)
	142	format();
	143
	144	hash_algo = argv[0];
	145	private_key_name = argv[1];
	146	x509_name = argv[2];
	147	module_name = argv[3];
	148	if (argc == 5) {
	149	dest_name = argv[4];
	150	replace_orig = false;
	151	} else {
	152	ERR(asprintf(&dest_name, "%s.~signed~", module_name) < 0,
	153	"asprintf");
	154	replace_orig = true;
	155	}
	156
	157	/* Read the private key and the X.509 cert the PKCS#7 message
	158	* will point to.
	159	*/
6e3e281f DW	160	if (!strncmp(private_key_name, "pkcs11:", 7)) {
	161	ENGINE *e;
	162
	163	ENGINE_load_builtin_engines();
	164	drain_openssl_errors();
	165	e = ENGINE_by_id("pkcs11");
	166	ERR(!e, "Load PKCS#11 ENGINE");
	167	if (ENGINE_init(e))
	168	drain_openssl_errors();
	169	else
	170	ERR(1, "ENGINE_init");
	171	if (key_pass)
	172	ERR(!ENGINE_ctrl_cmd_string(e, "PIN", key_pass, 0), "Set PKCS#11 PIN");
	173	private_key = ENGINE_load_private_key(e, private_key_name, NULL,
	174	NULL);
	175	ERR(!private_key, "%s", private_key_name);
	176	} else {
	177	b = BIO_new_file(private_key_name, "rb");
	178	ERR(!b, "%s", private_key_name);
	179	private_key = PEM_read_bio_PrivateKey(b, NULL, pem_pw_cb, NULL);
	180	ERR(!private_key, "%s", private_key_name);
	181	BIO_free(b);
	182	}
bc1c373d DH	183
	184	b = BIO_new_file(x509_name, "rb");
	185	ERR(!b, "%s", x509_name);
	186	x509 = d2i_X509_bio(b, NULL); /* Binary encoded X.509 */
	187	if (!x509) {
e9a5e8cc	188	ERR(BIO_reset(b) != 1, "%s", x509_name);
bc1c373d DH	189	x509 = PEM_read_bio_X509(b, NULL, NULL, NULL); /* PEM encoded X.509 */
	190	if (x509)
	191	drain_openssl_errors();
	192	}
	193	BIO_free(b);
	194	ERR(!x509, "%s", x509_name);
	195
	196	/* Open the destination file now so that we can shovel the module data
	197	* across as we read it.
	198	*/
23dfbbab LR	199	if (!sign_only) {
	200	bd = BIO_new_file(dest_name, "wb");
	201	ERR(!bd, "%s", dest_name);
	202	}
bc1c373d DH	203
	204	/* Digest the module data. */
	205	OpenSSL_add_all_digests();
	206	display_openssl_errors(__LINE__);
	207	digest_algo = EVP_get_digestbyname(hash_algo);
	208	ERR(!digest_algo, "EVP_get_digestbyname");
	209
	210	bm = BIO_new_file(module_name, "rb");
	211	ERR(!bm, "%s", module_name);
	212
ed8c2076 DH	213	/* Load the CMS message from the digest buffer. */
	214	cms = CMS_sign(NULL, NULL, NULL, NULL,
	215	CMS_NOCERTS \| CMS_PARTIAL \| CMS_BINARY \| CMS_DETACHED \| CMS_STREAM);
	216	ERR(!cms, "CMS_sign");
bc1c373d	217
ed8c2076	218	ERR(!CMS_add1_signer(cms, x509, private_key, digest_algo,
99db4435 DH	219	CMS_NOCERTS \| CMS_BINARY \| CMS_NOSMIMECAP \|
99db4435 DH	220	use_keyid \| use_signed_attrs),
ed8c2076 DH	221	"CMS_sign_add_signer");
	222	ERR(CMS_final(cms, bm, NULL, CMS_NOCERTS \| CMS_BINARY) < 0,
	223	"CMS_final");
bc1c373d	224
ed8c2076 DH	225	if (save_cms) {
ed8c2076 DH	226	char *cms_name;
bc1c373d	227
ed8c2076 DH	228	ERR(asprintf(&cms_name, "%s.p7s", module_name) < 0, "asprintf");
	229	b = BIO_new_file(cms_name, "wb");
	230	ERR(!b, "%s", cms_name);
	231	ERR(i2d_CMS_bio_stream(b, cms, NULL, 0) < 0, "%s", cms_name);
bc1c373d DH	232	BIO_free(b);
	233	}
	234
23dfbbab LR	235	if (sign_only)
	236	return 0;
	237
bc1c373d DH	238	/* Append the marker and the PKCS#7 message to the destination file */
	239	ERR(BIO_reset(bm) < 0, "%s", module_name);
	240	while ((n = BIO_read(bm, buf, sizeof(buf))),
	241	n > 0) {
	242	ERR(BIO_write(bd, buf, n) < 0, "%s", dest_name);
	243	}
	244	ERR(n < 0, "%s", module_name);
	245	module_size = BIO_number_written(bd);
	246
ed8c2076 DH	247	ERR(i2d_CMS_bio_stream(bd, cms, NULL, 0) < 0, "%s", dest_name);
	248	cms_size = BIO_number_written(bd) - module_size;
	249	sig_info.sig_len = htonl(cms_size);
bc1c373d DH	250	ERR(BIO_write(bd, &sig_info, sizeof(sig_info)) < 0, "%s", dest_name);
	251	ERR(BIO_write(bd, magic_number, sizeof(magic_number) - 1) < 0, "%s", dest_name);
	252
	253	ERR(BIO_free(bd) < 0, "%s", dest_name);
	254
	255	/* Finally, if we're signing in place, replace the original. */
	256	if (replace_orig)
	257	ERR(rename(dest_name, module_name) < 0, "%s", dest_name);
	258
	259	return 0;
	260	}