[thirdparty/kernel/linux.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/pkcs7.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_pkcs7 = false, replace_orig;
	bool sign_only = false;
	unsigned char buf[4096];
	unsigned long module_size, pkcs7_size;
	const EVP_MD *digest_algo;
	EVP_PKEY *private_key;
	PKCS7 *pkcs7;
	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, "dp");
		switch (opt) {
		case 'p': save_pkcs7 = true; break;
		case 'd': sign_only = true; save_pkcs7 = true; 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) {
		BIO_reset(b);
		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 PKCS#7 message from the digest buffer. */
	pkcs7 = PKCS7_sign(NULL, NULL, NULL, NULL,
			   PKCS7_NOCERTS | PKCS7_PARTIAL | PKCS7_BINARY | PKCS7_DETACHED | PKCS7_STREAM);
	ERR(!pkcs7, "PKCS7_sign");

	ERR(!PKCS7_sign_add_signer(pkcs7, x509, private_key, digest_algo, PKCS7_NOCERTS | PKCS7_BINARY),
	    "PKCS7_sign_add_signer");
	ERR(PKCS7_final(pkcs7, bm, PKCS7_NOCERTS | PKCS7_BINARY) < 0,
	    "PKCS7_final");

	if (save_pkcs7) {
		char *pkcs7_name;

		ERR(asprintf(&pkcs7_name, "%s.pkcs7", module_name) < 0, "asprintf");
		b = BIO_new_file(pkcs7_name, "wb");
		ERR(!b, "%s", pkcs7_name);
		ERR(i2d_PKCS7_bio_stream(b, pkcs7, NULL, 0) < 0, "%s", pkcs7_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_PKCS7_bio_stream(bd, pkcs7, NULL, 0) < 0, "%s", dest_name);
	pkcs7_size = BIO_number_written(bd) - module_size;
	sig_info.sig_len = htonl(pkcs7_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>
	23	#include <openssl/pkcs7.h>
	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;
	110	bool save_pkcs7 = false, replace_orig;
23dfbbab	111	bool sign_only = false;
bc1c373d DH	112	unsigned char buf[4096];
	113	unsigned long module_size, pkcs7_size;
	114	const EVP_MD *digest_algo;
	115	EVP_PKEY *private_key;
	116	PKCS7 *pkcs7;
	117	X509 *x509;
23dfbbab	118	BIO b, bd = NULL, *bm;
bc1c373d DH	119	int opt, n;
bc1c373d DH	120
af1eb291	121	OpenSSL_add_all_algorithms();
bc1c373d DH	122	ERR_load_crypto_strings();
	123	ERR_clear_error();
	124
af1eb291 DW	125	key_pass = getenv("KBUILD_SIGN_PIN");
af1eb291 DW	126
bc1c373d DH	127	do {
	128	opt = getopt(argc, argv, "dp");
	129	switch (opt) {
	130	case 'p': save_pkcs7 = true; break;
23dfbbab	131	case 'd': sign_only = true; save_pkcs7 = true; break;
bc1c373d DH	132	case -1: break;
	133	default: format();
	134	}
	135	} while (opt != -1);
	136
	137	argc -= optind;
	138	argv += optind;
	139	if (argc < 4 \|\| argc > 5)
	140	format();
	141
	142	hash_algo = argv[0];
	143	private_key_name = argv[1];
	144	x509_name = argv[2];
	145	module_name = argv[3];
	146	if (argc == 5) {
	147	dest_name = argv[4];
	148	replace_orig = false;
	149	} else {
	150	ERR(asprintf(&dest_name, "%s.~signed~", module_name) < 0,
	151	"asprintf");
	152	replace_orig = true;
	153	}
	154
	155	/* Read the private key and the X.509 cert the PKCS#7 message
	156	* will point to.
	157	*/
6e3e281f DW	158	if (!strncmp(private_key_name, "pkcs11:", 7)) {
	159	ENGINE *e;
	160
	161	ENGINE_load_builtin_engines();
	162	drain_openssl_errors();
	163	e = ENGINE_by_id("pkcs11");
	164	ERR(!e, "Load PKCS#11 ENGINE");
	165	if (ENGINE_init(e))
	166	drain_openssl_errors();
	167	else
	168	ERR(1, "ENGINE_init");
	169	if (key_pass)
	170	ERR(!ENGINE_ctrl_cmd_string(e, "PIN", key_pass, 0), "Set PKCS#11 PIN");
	171	private_key = ENGINE_load_private_key(e, private_key_name, NULL,
	172	NULL);
	173	ERR(!private_key, "%s", private_key_name);
	174	} else {
	175	b = BIO_new_file(private_key_name, "rb");
	176	ERR(!b, "%s", private_key_name);
	177	private_key = PEM_read_bio_PrivateKey(b, NULL, pem_pw_cb, NULL);
	178	ERR(!private_key, "%s", private_key_name);
	179	BIO_free(b);
	180	}
bc1c373d DH	181
	182	b = BIO_new_file(x509_name, "rb");
	183	ERR(!b, "%s", x509_name);
	184	x509 = d2i_X509_bio(b, NULL); /* Binary encoded X.509 */
	185	if (!x509) {
	186	BIO_reset(b);
	187	x509 = PEM_read_bio_X509(b, NULL, NULL, NULL); /* PEM encoded X.509 */
	188	if (x509)
	189	drain_openssl_errors();
	190	}
	191	BIO_free(b);
	192	ERR(!x509, "%s", x509_name);
	193
	194	/* Open the destination file now so that we can shovel the module data
	195	* across as we read it.
	196	*/
23dfbbab LR	197	if (!sign_only) {
	198	bd = BIO_new_file(dest_name, "wb");
	199	ERR(!bd, "%s", dest_name);
	200	}
bc1c373d DH	201
	202	/* Digest the module data. */
	203	OpenSSL_add_all_digests();
	204	display_openssl_errors(__LINE__);
	205	digest_algo = EVP_get_digestbyname(hash_algo);
	206	ERR(!digest_algo, "EVP_get_digestbyname");
	207
	208	bm = BIO_new_file(module_name, "rb");
	209	ERR(!bm, "%s", module_name);
	210
	211	/* Load the PKCS#7 message from the digest buffer. */
	212	pkcs7 = PKCS7_sign(NULL, NULL, NULL, NULL,
	213	PKCS7_NOCERTS \| PKCS7_PARTIAL \| PKCS7_BINARY \| PKCS7_DETACHED \| PKCS7_STREAM);
	214	ERR(!pkcs7, "PKCS7_sign");
	215
	216	ERR(!PKCS7_sign_add_signer(pkcs7, x509, private_key, digest_algo, PKCS7_NOCERTS \| PKCS7_BINARY),
	217	"PKCS7_sign_add_signer");
	218	ERR(PKCS7_final(pkcs7, bm, PKCS7_NOCERTS \| PKCS7_BINARY) < 0,
	219	"PKCS7_final");
	220
	221	if (save_pkcs7) {
	222	char *pkcs7_name;
	223
	224	ERR(asprintf(&pkcs7_name, "%s.pkcs7", module_name) < 0, "asprintf");
	225	b = BIO_new_file(pkcs7_name, "wb");
	226	ERR(!b, "%s", pkcs7_name);
	227	ERR(i2d_PKCS7_bio_stream(b, pkcs7, NULL, 0) < 0, "%s", pkcs7_name);
	228	BIO_free(b);
	229	}
	230
23dfbbab LR	231	if (sign_only)
	232	return 0;
	233
bc1c373d DH	234	/* Append the marker and the PKCS#7 message to the destination file */
	235	ERR(BIO_reset(bm) < 0, "%s", module_name);
	236	while ((n = BIO_read(bm, buf, sizeof(buf))),
	237	n > 0) {
	238	ERR(BIO_write(bd, buf, n) < 0, "%s", dest_name);
	239	}
	240	ERR(n < 0, "%s", module_name);
	241	module_size = BIO_number_written(bd);
	242
	243	ERR(i2d_PKCS7_bio_stream(bd, pkcs7, NULL, 0) < 0, "%s", dest_name);
	244	pkcs7_size = BIO_number_written(bd) - module_size;
	245	sig_info.sig_len = htonl(pkcs7_size);
	246	ERR(BIO_write(bd, &sig_info, sizeof(sig_info)) < 0, "%s", dest_name);
	247	ERR(BIO_write(bd, magic_number, sizeof(magic_number) - 1) < 0, "%s", dest_name);
	248
	249	ERR(BIO_free(bd) < 0, "%s", dest_name);
	250
	251	/* Finally, if we're signing in place, replace the original. */
	252	if (replace_orig)
	253	ERR(rename(dest_name, module_name) < 0, "%s", dest_name);
	254
	255	return 0;
	256	}