ddns-confgen.c revision 0c27b3fe77ac1d5094ba3521e8142d9e7973133f
/*
* Copyright (C) 2009, 2011, 2014, 2016 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 http://mozilla.org/MPL/2.0/.
*/
/*! \file */
/**
* ddns-confgen generates configuration files for dynamic DNS. It can
* be used as a convenient alternative to writing the ddns.key file
* and the corresponding key and update-policy statements in named.conf.
*/
#include <config.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>
#ifdef PKCS11CRYPTO
#include <pk11/result.h>
#endif
#include <dns/keyvalues.h>
#include <dns/name.h>
#include <dns/result.h>
#include <dst/dst.h>
#include <confgen/os.h>
#include "util.h"
#include "keygen.h"
#define KEYGEN_DEFAULT "tsig-key"
#define CONFGEN_DEFAULT "ddns-key"
static char program[256];
const char *progname;
static enum { progmode_keygen, progmode_confgen} progmode;
isc_boolean_t verbose = ISC_FALSE; /* needed by util.c but not used here */
ISC_PLATFORM_NORETURN_PRE static void
usage(int status) ISC_PLATFORM_NORETURN_POST;
static void
usage(int status) {
if (progmode == progmode_confgen) {
fprintf(stderr, "\
Usage:\n\
%s [-a alg] [-k keyname] [-r randomfile] [-q] [-s name | -z zone]\n\
-a alg: algorithm (default hmac-sha256)\n\
-k keyname: name of the key as it will be used in named.conf\n\
-r randomfile: source of random data (use \"keyboard\" for key timing)\n\
-s name: domain name to be updated using the created key\n\
-z zone: name of the zone as it will be used in named.conf\n\
-q: quiet mode: print the key, with no explanatory text\n",
progname);
} else {
fprintf(stderr, "\
Usage:\n\
%s [-a alg] [-r randomfile] [keyname]\n\
-a alg: algorithm (default hmac-sha256)\n\
-r randomfile: source of random data (use \"keyboard\" for key timing)\n",
progname);
}
exit (status);
}
int
main(int argc, char **argv) {
isc_result_t result = ISC_R_SUCCESS;
isc_boolean_t show_final_mem = ISC_FALSE;
isc_boolean_t quiet = ISC_FALSE;
isc_buffer_t key_txtbuffer;
char key_txtsecret[256];
isc_mem_t *mctx = NULL;
const char *randomfile = NULL;
const char *keyname = NULL;
const char *zone = NULL;
const char *self_domain = NULL;
char *keybuf = NULL;
dns_secalg_t alg = DST_ALG_HMACSHA256;
const char *algname;
int keysize = 256;
int len = 0;
int ch;
#ifdef PKCS11CRYPTO
pk11_result_register();
#endif
dns_result_register();
result = isc_file_progname(*argv, program, sizeof(program));
if (result != ISC_R_SUCCESS)
memmove(program, "tsig-keygen", 11);
progname = program;
/*
* Libtool doesn't preserve the program name prior to final
* installation. Remove the libtool prefix ("lt-").
*/
if (strncmp(progname, "lt-", 3) == 0)
progname += 3;
#define PROGCMP(X) \
(strcasecmp(progname, X) == 0 || strcasecmp(progname, X ".exe") == 0)
if (PROGCMP("tsig-keygen")) {
progmode = progmode_keygen;
quiet = ISC_TRUE;
} else if (PROGCMP("ddns-confgen"))
progmode = progmode_confgen;
else
INSIST(0);
isc_commandline_errprint = ISC_FALSE;
while ((ch = isc_commandline_parse(argc, argv,
"a:hk:Mmr:qs:y:z:")) != -1) {
switch (ch) {
case 'a':
algname = isc_commandline_argument;
alg = alg_fromtext(algname);
if (alg == DST_ALG_UNKNOWN)
fatal("Unsupported algorithm '%s'", algname);
keysize = alg_bits(alg);
break;
case 'h':
usage(0);
case 'k':
case 'y':
if (progmode == progmode_confgen)
keyname = isc_commandline_argument;
else
usage(1);
break;
case 'M':
isc_mem_debugging = ISC_MEM_DEBUGTRACE;
break;
case 'm':
show_final_mem = ISC_TRUE;
break;
case 'q':
if (progmode == progmode_confgen)
quiet = ISC_TRUE;
else
usage(1);
break;
case 'r':
randomfile = isc_commandline_argument;
break;
case 's':
if (progmode == progmode_confgen)
self_domain = isc_commandline_argument;
else
usage(1);
break;
case 'z':
if (progmode == progmode_confgen)
zone = isc_commandline_argument;
else
usage(1);
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);
}
}
if (progmode == progmode_keygen)
keyname = argv[isc_commandline_index++];
POST(argv);
if (self_domain != NULL && zone != NULL)
usage(1); /* -s and -z cannot coexist */
if (argc > isc_commandline_index)
usage(1);
/* Use canonical algorithm name */
algname = alg_totext(alg);
DO("create memory context", isc_mem_create(0, 0, &mctx));
if (keyname == NULL) {
const char *suffix = NULL;
keyname = ((progmode == progmode_keygen)
? KEYGEN_DEFAULT
: CONFGEN_DEFAULT);
if (self_domain != NULL)
suffix = self_domain;
else if (zone != NULL)
suffix = zone;
if (suffix != NULL) {
len = strlen(keyname) + strlen(suffix) + 2;
keybuf = isc_mem_get(mctx, len);
if (keybuf == NULL)
fatal("failed to allocate memory for keyname");
snprintf(keybuf, len, "%s.%s", keyname, suffix);
keyname = (const char *) keybuf;
}
}
isc_buffer_init(&key_txtbuffer, &key_txtsecret, sizeof(key_txtsecret));
generate_key(mctx, randomfile, alg, keysize, &key_txtbuffer);
if (!quiet)
printf("\
# To activate this key, place the following in named.conf, and\n\
# in a separate keyfile on the system or systems from which nsupdate\n\
# will be run:\n");
printf("\
key \"%s\" {\n\
algorithm %s;\n\
secret \"%.*s\";\n\
};\n",
keyname, algname,
(int)isc_buffer_usedlength(&key_txtbuffer),
(char *)isc_buffer_base(&key_txtbuffer));
if (!quiet) {
if (self_domain != NULL) {
printf("\n\
# Then, in the \"zone\" statement for the zone containing the\n\
# name \"%s\", place an \"update-policy\" statement\n\
# like this one, adjusted as needed for your preferred permissions:\n\
update-policy {\n\
grant %s name %s ANY;\n\
};\n",
self_domain, keyname, self_domain);
} else if (zone != NULL) {
printf("\n\
# Then, in the \"zone\" definition statement for \"%s\",\n\
# place an \"update-policy\" statement like this one, adjusted as \n\
# needed for your preferred permissions:\n\
update-policy {\n\
grant %s zonesub ANY;\n\
};\n",
zone, keyname);
} else {
printf("\n\
# Then, in the \"zone\" statement for each zone you wish to dynamically\n\
# update, place an \"update-policy\" statement granting update permission\n\
# to this key. For example, the following statement grants this key\n\
# permission to update any name within the zone:\n\
update-policy {\n\
grant %s zonesub ANY;\n\
};\n",
keyname);
}
printf("\n\
# After the keyfile has been placed, the following command will\n\
# execute nsupdate using this key:\n\
nsupdate -k <keyfile>\n");
}
if (keybuf != NULL)
isc_mem_put(mctx, keybuf, len);
if (show_final_mem)
isc_mem_stats(mctx, stderr);
isc_mem_destroy(&mctx);
return (0);
}