smime.c

来自「一个用于点对点传输加密的工具包源码」· C语言 代码 · 共 549 行 · 第 1/2 页

		BIO_printf (bio_err, "-noattr        don't include any signed attributes\n");
		BIO_printf (bio_err, "-binary        don't translate message to text\n");
		BIO_printf (bio_err, "-certfile file other certificates file\n");
		BIO_printf (bio_err, "-signer file   signer certificate file\n");
		BIO_printf (bio_err, "-recip  file   recipient certificate file for decryption\n");
		BIO_printf (bio_err, "-in file       input file\n");
		BIO_printf (bio_err, "-inform arg    input format SMIME (default), PEM or DER\n");
		BIO_printf (bio_err, "-inkey file    input private key (if not signer or recipient)\n");
		BIO_printf (bio_err, "-out file      output file\n");
		BIO_printf (bio_err, "-outform arg   output format SMIME (default), PEM or DER\n");
		BIO_printf (bio_err, "-content file  supply or override content for detached signature\n");
		BIO_printf (bio_err, "-to addr       to address\n");
		BIO_printf (bio_err, "-from ad       from address\n");
		BIO_printf (bio_err, "-subject s     subject\n");
		BIO_printf (bio_err, "-text          include or delete text MIME headers\n");
		BIO_printf (bio_err, "-CApath dir    trusted certificates directory\n");
		BIO_printf (bio_err, "-CAfile file   trusted certificates file\n");
		BIO_printf(bio_err,  "-rand file%cfile%c...\n", LIST_SEPARATOR_CHAR, LIST_SEPARATOR_CHAR);
		BIO_printf(bio_err,  "               load the file (or the files in the directory) into\n");
		BIO_printf(bio_err,  "               the random number generator\n");
		BIO_printf (bio_err, "cert.pem       recipient certificate(s) for encryption\n");
		goto end;
	}

	if(!app_passwd(bio_err, passargin, NULL, &passin, NULL)) {
		BIO_printf(bio_err, "Error getting password\n");
		goto end;
	}

	if (need_rand) {
		app_RAND_load_file(NULL, bio_err, (inrand != NULL));
		if (inrand != NULL)
			BIO_printf(bio_err,"%ld semi-random bytes loaded\n",
				app_RAND_load_files(inrand));
	}

	ret = 2;

	if(operation != SMIME_SIGN) flags &= ~PKCS7_DETACHED;

	if(operation & SMIME_OP) {
		if(flags & PKCS7_BINARY) inmode = "rb";
		if(outformat == FORMAT_ASN1) outmode = "wb";
	} else {
		if(flags & PKCS7_BINARY) outmode = "wb";
		if(informat == FORMAT_ASN1) inmode = "rb";
	}

	if(operation == SMIME_ENCRYPT) {
		if (!cipher) {
#ifndef NO_RC2			
			cipher = EVP_rc2_40_cbc();
#else
			BIO_printf(bio_err, "No cipher selected\n");
			goto end;
#endif
		}
		encerts = sk_X509_new_null();
		while (*args) {
			if(!(cert = load_cert(bio_err,*args,FORMAT_PEM))) {
				BIO_printf(bio_err, "Can't read recipient certificate file %s\n", *args);
				goto end;
			}
			sk_X509_push(encerts, cert);
			cert = NULL;
			args++;
		}
	}

	if(signerfile && (operation == SMIME_SIGN)) {
		if(!(signer = load_cert(bio_err,signerfile,FORMAT_PEM))) {
			BIO_printf(bio_err, "Can't read signer certificate file %s\n", signerfile);
			goto end;
		}
	}

	if(certfile) {
		if(!(other = load_certs(bio_err,certfile,FORMAT_PEM))) {
			BIO_printf(bio_err, "Can't read certificate file %s\n", certfile);
			ERR_print_errors(bio_err);
			goto end;
		}
	}

	if(recipfile && (operation == SMIME_DECRYPT)) {
		if(!(recip = load_cert(bio_err,recipfile,FORMAT_PEM))) {
			BIO_printf(bio_err, "Can't read recipient certificate file %s\n", recipfile);
			ERR_print_errors(bio_err);
			goto end;
		}
	}

	if(operation == SMIME_DECRYPT) {
		if(!keyfile) keyfile = recipfile;
	} else if(operation == SMIME_SIGN) {
		if(!keyfile) keyfile = signerfile;
	} else keyfile = NULL;

	if(keyfile) {
		if(!(key = load_key(bio_err,keyfile, FORMAT_PEM, passin))) {
			BIO_printf(bio_err, "Can't read recipient certificate file %s\n", keyfile);
			ERR_print_errors(bio_err);
			goto end;
		}
	}

	if (infile) {
		if (!(in = BIO_new_file(infile, inmode))) {
			BIO_printf (bio_err,
				 "Can't open input file %s\n", infile);
			goto end;
		}
	} else in = BIO_new_fp(stdin, BIO_NOCLOSE);

	if (outfile) {
		if (!(out = BIO_new_file(outfile, outmode))) {
			BIO_printf (bio_err,
				 "Can't open output file %s\n", outfile);
			goto end;
		}
	} else {
		out = BIO_new_fp(stdout, BIO_NOCLOSE);
#ifdef VMS
		{
		    BIO *tmpbio = BIO_new(BIO_f_linebuffer());
		    out = BIO_push(tmpbio, out);
		}
#endif
	}

	if(operation == SMIME_VERIFY) {
		if(!(store = setup_verify(CAfile, CApath))) goto end;
	}

	ret = 3;

	if(operation == SMIME_ENCRYPT) {
		p7 = PKCS7_encrypt(encerts, in, cipher, flags);
	} else if(operation == SMIME_SIGN) {
		p7 = PKCS7_sign(signer, key, other, in, flags);
		BIO_reset(in);
	} else {
		if(informat == FORMAT_SMIME) 
			p7 = SMIME_read_PKCS7(in, &indata);
		else if(informat == FORMAT_PEM) 
			p7 = PEM_read_bio_PKCS7(in, NULL, NULL, NULL);
		else if(informat == FORMAT_ASN1) 
			p7 = d2i_PKCS7_bio(in, NULL);
		else {
			BIO_printf(bio_err, "Bad input format for PKCS#7 file\n");
			goto end;
		}

		if(!p7) {
			BIO_printf(bio_err, "Error reading S/MIME message\n");
			goto end;
		}
		if(contfile) {
			BIO_free(indata);
			if(!(indata = BIO_new_file(contfile, "rb"))) {
				BIO_printf(bio_err, "Can't read content file %s\n", contfile);
				goto end;
			}
		}
	}

	if(!p7) {
		BIO_printf(bio_err, "Error creating PKCS#7 structure\n");
		goto end;
	}

	ret = 4;
	if(operation == SMIME_DECRYPT) {
		if(!PKCS7_decrypt(p7, key, recip, out, flags)) {
			BIO_printf(bio_err, "Error decrypting PKCS#7 structure\n");
			goto end;
		}
	} else if(operation == SMIME_VERIFY) {
		STACK_OF(X509) *signers;
		if(PKCS7_verify(p7, other, store, indata, out, flags)) {
			BIO_printf(bio_err, "Verification Successful\n");
		} else {
			BIO_printf(bio_err, "Verification Failure\n");
			goto end;
		}
		signers = PKCS7_get0_signers(p7, other, flags);
		if(!save_certs(signerfile, signers)) {
			BIO_printf(bio_err, "Error writing signers to %s\n",
								signerfile);
			ret = 5;
			goto end;
		}
		sk_X509_free(signers);
	} else if(operation == SMIME_PK7OUT) {
		PEM_write_bio_PKCS7(out, p7);
	} else {
		if(to) BIO_printf(out, "To: %s\n", to);
		if(from) BIO_printf(out, "From: %s\n", from);
		if(subject) BIO_printf(out, "Subject: %s\n", subject);
		if(outformat == FORMAT_SMIME) 
			SMIME_write_PKCS7(out, p7, in, flags);
		else if(outformat == FORMAT_PEM) 
			PEM_write_bio_PKCS7(out,p7);
		else if(outformat == FORMAT_ASN1) 
			i2d_PKCS7_bio(out,p7);
		else {
			BIO_printf(bio_err, "Bad output format for PKCS#7 file\n");
			goto end;
		}
	}
	ret = 0;
end:
	if (need_rand)
		app_RAND_write_file(NULL, bio_err);
	if(ret) ERR_print_errors(bio_err);
	sk_X509_pop_free(encerts, X509_free);
	sk_X509_pop_free(other, X509_free);
	X509_STORE_free(store);
	X509_free(cert);
	X509_free(recip);
	X509_free(signer);
	EVP_PKEY_free(key);
	PKCS7_free(p7);
	BIO_free(in);
	BIO_free(indata);
	BIO_free_all(out);
	if(passin) OPENSSL_free(passin);
	return (ret);
}

static X509_STORE *setup_verify(char *CAfile, char *CApath)
{
	X509_STORE *store;
	X509_LOOKUP *lookup;
	if(!(store = X509_STORE_new())) goto end;
	lookup=X509_STORE_add_lookup(store,X509_LOOKUP_file());
	if (lookup == NULL) goto end;
	if (CAfile) {
		if(!X509_LOOKUP_load_file(lookup,CAfile,X509_FILETYPE_PEM)) {
			BIO_printf(bio_err, "Error loading file %s\n", CAfile);
			goto end;
		}
	} else X509_LOOKUP_load_file(lookup,NULL,X509_FILETYPE_DEFAULT);
		
	lookup=X509_STORE_add_lookup(store,X509_LOOKUP_hash_dir());
	if (lookup == NULL) goto end;
	if (CApath) {
		if(!X509_LOOKUP_add_dir(lookup,CApath,X509_FILETYPE_PEM)) {
			BIO_printf(bio_err, "Error loading directory %s\n", CApath);
			goto end;
		}
	} else X509_LOOKUP_add_dir(lookup,NULL,X509_FILETYPE_DEFAULT);

	ERR_clear_error();
	return store;
	end:
	X509_STORE_free(store);
	return NULL;
}

static int save_certs(char *signerfile, STACK_OF(X509) *signers)
{
	int i;
	BIO *tmp;
	if(!signerfile) return 1;
	tmp = BIO_new_file(signerfile, "w");
	if(!tmp) return 0;
	for(i = 0; i < sk_X509_num(signers); i++)
		PEM_write_bio_X509(tmp, sk_X509_value(signers, i));
	BIO_free(tmp);
	return 1;
}