GmSSL/tools/cmsdecrypt.c

/*
 * Copyright (c) 2021 - 2021 The GmSSL Project.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the GmSSL Project.
 *    (http://gmssl.org/)"
 *
 * 4. The name "GmSSL Project" must not be used to endorse or promote
 *    products derived from this software without prior written
 *    permission. For written permission, please contact
 *    guanzhi1980@gmail.com.
 *
 * 5. Products derived from this software may not be called "GmSSL"
 *    nor may "GmSSL" appear in their names without prior written
 *    permission of the GmSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the GmSSL Project
 *    (http://gmssl.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE GmSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE GmSSL PROJECT OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <gmssl/x509.h>
#include <gmssl/cms.h>



static const char *options = "-key file -pass str -cert file -in file [-out file]";

int cmsdecrypt_main(int argc, char **argv)
{
	int ret = 1;
	char *prog = argv[0];
	char *keyfile = NULL;
	char *pass = NULL;
	char *certfile = NULL;
	char *infile = NULL;
	char *outfile = NULL;
	FILE *keyfp = NULL;
	FILE *certfp = NULL;
	FILE *infp = NULL;
	FILE *outfp = stdout;
	uint8_t cert[1024];
	size_t certlen;
	struct stat st;
	uint8_t *cms = NULL;
	size_t cmslen, cms_maxlen;
	SM2_KEY key;
	int content_type;
	uint8_t *content = NULL;
	size_t content_len;
	const uint8_t *rcpt_infos;
	size_t rcpt_infos_len;
	const uint8_t *shared_info1;
	const uint8_t *shared_info2;
	size_t shared_info1_len, shared_info2_len;

	argc--;
	argv++;

	if (argc < 1) {
		fprintf(stderr, "usage: %s %s\n", prog, options);
		return 1;
	}

	while (argc > 1) {
		if (!strcmp(*argv, "-help")) {
			printf("usage: %s %s\n", prog, options);
			ret = 0;
			goto end;
		} else if (!strcmp(*argv, "-key")) {
			if (--argc < 1) goto bad;
			keyfile = *(++argv);
			if (!(keyfp = fopen(keyfile, "r"))) {
				fprintf(stderr, "%s: open '%s' failure : %s\n", prog, keyfile, strerror(errno));
				goto end;
			}
		} else if (!strcmp(*argv, "-pass")) {
			if (--argc < 1) goto bad;
			pass = *(++argv);
		} else if (!strcmp(*argv, "-cert")) {
			if (--argc < 1) goto bad;
			certfile = *(++argv);
			if (!(certfp = fopen(certfile, "r"))) {
				fprintf(stderr, "%s: open '%s' failure : %s\n", prog, certfile, strerror(errno));
				goto end;
			}
		} else if (!strcmp(*argv, "-in")) {
			if (--argc < 1) goto bad;
			infile = *(++argv);
			if (!(infp = fopen(infile, "r"))) {
				fprintf(stderr, "%s: open '%s' failure : %s\n", prog, infile, strerror(errno));
				goto end;
			}
		} else if (!strcmp(*argv, "-out")) {
			if (--argc < 1) goto bad;
			outfile = *(++argv);
			if (!(outfp = fopen(outfile, "w"))) {
				fprintf(stderr, "%s: open '%s' failure : %s\n", prog, outfile, strerror(errno));
				goto end;
			}
		} else {
			fprintf(stderr, "%s: illegal option '%s'\n", prog, *argv);
			goto end;
bad:
			fprintf(stderr, "%s: '%s' option value missing\n", prog, *argv);
			goto end;
		}

		argc--;
		argv++;
	}

	if (!keyfile) {
		fprintf(stderr, "%s: '-key' option required\n", prog);
		goto end;
	}
	if (!pass) {
		fprintf(stderr, "%s: '-pass' option required\n", prog);
		goto end;
	}
	if (!certfile) {
		fprintf(stderr, "%s: '-cert' option required\n", prog);
		goto end;
	}
	if (!infile) {
		fprintf(stderr, "%s: '-in' option required\n", prog);
		goto end;
	}

	if (sm2_private_key_info_decrypt_from_pem(&key, pass, keyfp) != 1) {
		fprintf(stderr, "%s: private key decryption failure\n", prog);
		goto end;
	}
	if (x509_cert_from_pem(cert, &certlen, sizeof(cert), certfp) != 1) {
		fprintf(stderr, "%s: load certificate failure\n", prog);
		goto end;
	}

	fstat(fileno(infp), &st);
	cms_maxlen = (st.st_size * 3)/4 + 1;
	if (!(cms = malloc(cms_maxlen))) {
		fprintf(stderr, "%s: malloc failure\n", prog);
		goto end;
	}
	if (cms_from_pem(cms, &cmslen, cms_maxlen, infp) != 1) {
		fprintf(stderr, "%s: read CMS failure\n", prog);
		goto end;
	}

	if (!(content = malloc(cmslen))) {
		fprintf(stderr, "%s: malloc failure\n", prog);
		goto end;
	}

	if (cms_deenvelop(cms, cmslen,
		&key, cert, certlen,
		&content_type, content, &content_len,
		&rcpt_infos, &rcpt_infos_len,
		&shared_info1, &shared_info1_len,
		&shared_info2, &shared_info2_len) != 1) {
		fprintf(stderr, "%s: decryption failure\n", prog);
		goto end;
	}
	if (content_type != OID_cms_data) {
		fprintf(stderr, "%s: invalid CMS content type: %s\n", prog, cms_content_type_name(content_type));
		goto end;
	}

	if (fwrite(content, 1, content_len, outfp) != content_len) {
		fprintf(stderr, "%s: output failure : %s\n", prog, strerror(errno));
		goto end;
	}

	ret = 0;

end:
	if (infile && infp) fclose(infp);
	if (outfile && outfp) fclose(outfp);
	if (keyfile && keyfp) fclose(keyfp);
	if (cms) free(cms);
	if (content) free(content);
	return ret;
}