/*

 * Copyright (C) Internet Systems Consortium, Inc. ("ISC")

 *

 * This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, you can obtain one at https://mozilla.org/MPL/2.0/.

 *

 * See the COPYRIGHT file distributed with this work for additional

 * information regarding copyright ownership.

 */

/*! \file */

/**

 * rndc-confgen generates configuration files for rndc. It can be used

 * as a convenient alternative to writing the rndc.conf file and the

 * corresponding controls and key statements in named.conf by hand.

 * Alternatively, it can be run with the -a option to set up a

 * rndc.key file and avoid the need for a rndc.conf file and a

 * controls statement altogether.

 */

#include <config.h>

#include <stdbool.h>

#include <stdlib.h>

#include <stdarg.h>

#include <isc/assertions.h>

#include <isc/base64.h>

#include <isc/buffer.h>

#include <isc/commandline.h>

#include <isc/entropy.h>

#include <isc/file.h>

#include <isc/keyboard.h>

#include <isc/mem.h>

#include <isc/net.h>

#include <isc/print.h>

#include <isc/result.h>

#include <isc/string.h>

#include <isc/time.h>

#include <isc/util.h>

#include <pk11/site.h>

#include <dns/keyvalues.h>

#include <dns/name.h>

#include <dst/dst.h>

#include <confgen/os.h>

#include "util.h"

#include "keygen.h"

#define DEFAULT_KEYNAME		"rndc-key"

#define DEFAULT_SERVER		"127.0.0.1"

#define DEFAULT_PORT		953

static char program[256];

const char *progname;

bool verbose = false;

const char *keyfile, *keydef;

ISC_PLATFORM_NORETURN_PRE static void

usage(int status) ISC_PLATFORM_NORETURN_POST;

static void

usage(int status) {

#ifndef PK11_MD5_DISABLE

	fprintf(stderr, "\

Usage:\n\

 %s [-a] [-b bits] [-c keyfile] [-k keyname] [-p port] [-r randomfile] \

[-s addr] [-t chrootdir] [-u user]\n\

  -a:		 generate just the key clause and write it to keyfile (%s)\n\

  -A alg:	 algorithm (default hmac-md5)\n\

  -b bits:	 from 1 through 512, default 256; total length of the secret\n\

  -c keyfile:	 specify an alternate key file (requires -a)\n\

  -k keyname:	 the name as it will be used  in named.conf and rndc.conf\n\

  -p port:	 the port named will listen on and rndc will connect to\n\

  -r randomfile: source of random data (use \"keyboard\" for key timing)\n\

  -s addr:	 the address to which rndc should connect\n\

  -t chrootdir:	 write a keyfile in chrootdir as well (requires -a)\n\

  -u user:	 set the keyfile owner to \"user\" (requires -a)\n",

		 progname, keydef);

#else

	fprintf(stderr, "\

Usage:\n\

 %s [-a] [-b bits] [-c keyfile] [-k keyname] [-p port] [-r randomfile] \

[-s addr] [-t chrootdir] [-u user]\n\

  -a:		 generate just the key clause and write it to keyfile (%s)\n\

  -A alg:	 algorithm (default hmac-sha256)\n\

  -b bits:	 from 1 through 512, default 256; total length of the secret\n\

  -c keyfile:	 specify an alternate key file (requires -a)\n\

  -k keyname:	 the name as it will be used  in named.conf and rndc.conf\n\

  -p port:	 the port named will listen on and rndc will connect to\n\

  -r randomfile: source of random data (use \"keyboard\" for key timing)\n\

  -s addr:	 the address to which rndc should connect\n\

  -t chrootdir:	 write a keyfile in chrootdir as well (requires -a)\n\

  -u user:	 set the keyfile owner to \"user\" (requires -a)\n",

		 progname, keydef);

#endif

	exit (status);

}

int

main(int argc, char **argv) {

	bool show_final_mem = false;

	isc_buffer_t key_txtbuffer;

	char key_txtsecret[256];

	isc_mem_t *mctx = NULL;

	isc_result_t result = ISC_R_SUCCESS;

	const char *keyname = NULL;

	const char *randomfile = NULL;

	const char *serveraddr = NULL;

	dns_secalg_t alg;

	const char *algname;

	char *p;

	int ch;

	int port;

	int keysize = -1;

	struct in_addr addr4_dummy;

	struct in6_addr addr6_dummy;

	char *chrootdir = NULL;

	char *user = NULL;

	bool keyonly = false;

	int len;

	keydef = keyfile = RNDC_KEYFILE;

	result = isc_file_progname(*argv, program, sizeof(program));

	if (result != ISC_R_SUCCESS)

		memmove(program, "rndc-confgen", 13);

	progname = program;

	keyname = DEFAULT_KEYNAME;

#ifndef PK11_MD5_DISABLE

	alg = DST_ALG_HMACMD5;

#else

	alg = DST_ALG_HMACSHA256;

#endif

	serveraddr = DEFAULT_SERVER;

	port = DEFAULT_PORT;

	isc_commandline_errprint = false;

	while ((ch = isc_commandline_parse(argc, argv,

					   "aA:b:c:hk:Mmp:r:s:t:u:Vy")) != -1)

	{

		switch (ch) {

		case 'a':

			keyonly = true;

			break;

		case 'A':

			algname = isc_commandline_argument;

			alg = alg_fromtext(algname);

			if (alg == DST_ALG_UNKNOWN)

				fatal("Unsupported algorithm '%s'", algname);

			break;

		case 'b':

			keysize = strtol(isc_commandline_argument, &p, 10);

			if (*p != '\0' || keysize < 0)

				fatal("-b requires a non-negative number");

			break;

		case 'c':

			keyfile = isc_commandline_argument;

			break;

		case 'h':

			usage(0);

		case 'k':

		case 'y':	/* Compatible with rndc -y. */

			keyname = isc_commandline_argument;

			break;

		case 'M':

			isc_mem_debugging = ISC_MEM_DEBUGTRACE;

			break;

		case 'm':

			show_final_mem = true;

			break;

		case 'p':

			port = strtol(isc_commandline_argument, &p, 10);

			if (*p != '\0' || port < 0 || port > 65535)

				fatal("port '%s' out of range",

				      isc_commandline_argument);

			break;

		case 'r':

			randomfile = isc_commandline_argument;

			break;

		case 's':

			serveraddr = isc_commandline_argument;

			if (inet_pton(AF_INET, serveraddr, &addr4_dummy) != 1 &&

			    inet_pton(AF_INET6, serveraddr, &addr6_dummy) != 1)

				fatal("-s should be an IPv4 or IPv6 address");

			break;

		case 't':

			chrootdir = isc_commandline_argument;

			break;

		case 'u':

			user = isc_commandline_argument;

			break;

		case 'V':

			verbose = true;

			break;

		case '?':

			if (isc_commandline_option != '?') {

				fprintf(stderr, "%s: invalid argument -%c\n",

					program, isc_commandline_option);

				usage(1);

			} else

				usage(0);

			break;

		default:

			fprintf(stderr, "%s: unhandled option -%c\n",

				program, isc_commandline_option);

			exit(1);

		}

	}

	argc -= isc_commandline_index;

	argv += isc_commandline_index;

	POST(argv);

	if (argc > 0)

		usage(1);

	if (keysize < 0)

		keysize = alg_bits(alg);

	algname = alg_totext(alg);

	DO("create memory context", isc_mem_create(0, 0, &mctx));

	isc_buffer_init(&key_txtbuffer, &key_txtsecret, sizeof(key_txtsecret));

	generate_key(mctx, randomfile, alg, keysize, &key_txtbuffer);

	if (keyonly) {

		write_key_file(keyfile, chrootdir == NULL ? user : NULL,

			       keyname, &key_txtbuffer, alg);

		if (chrootdir != NULL) {

			char *buf;

			len = strlen(chrootdir) + strlen(keyfile) + 2;

			buf = isc_mem_get(mctx, len);

			if (buf == NULL)

				fatal("isc_mem_get(%d) failed\n", len);

			snprintf(buf, len, "%s%s%s", chrootdir,

				 (*keyfile != '/') ? "/" : "", keyfile);

			write_key_file(buf, user, keyname, &key_txtbuffer, alg);

			isc_mem_put(mctx, buf, len);

		}

	} else {

		printf("\

# Start of rndc.conf\n\

key \"%s\" {\n\

	algorithm %s;\n\

	secret \"%.*s\";\n\

};\n\

\n\

options {\n\

	default-key \"%s\";\n\

	default-server %s;\n\

	default-port %d;\n\

};\n\

# End of rndc.conf\n\

\n\

# Use with the following in named.conf, adjusting the allow list as needed:\n\

# key \"%s\" {\n\

# 	algorithm %s;\n\

# 	secret \"%.*s\";\n\

# };\n\

# \n\

# controls {\n\

# 	inet %s port %d\n\

# 		allow { %s; } keys { \"%s\"; };\n\

# };\n\

# End of named.conf\n",

		       keyname, algname,

		       (int)isc_buffer_usedlength(&key_txtbuffer),

		       (char *)isc_buffer_base(&key_txtbuffer),

		       keyname, serveraddr, port,

		       keyname, algname,

		       (int)isc_buffer_usedlength(&key_txtbuffer),

		       (char *)isc_buffer_base(&key_txtbuffer),

		       serveraddr, port, serveraddr, keyname);

	}

	if (show_final_mem)

		isc_mem_stats(mctx, stderr);

	isc_mem_destroy(&mctx);

	return (0);

}