1 files changed, 311 insertions, 0 deletions
diff --git a/bin/confgen/ddns-confgen.c b/bin/confgen/ddns-confgen.c
new file mode 100644
index 0000000..0afe087
--- /dev/null
+++ b/bin/confgen/ddns-confgen.c
@@ -0,0 +1,311 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * 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 */
+
+/**
+ * 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 <stdarg.h>
+#include <stdbool.h>
+#include <stdlib.h>
+
+#include <isc/assertions.h>
+#include <isc/base64.h>
+#include <isc/buffer.h>
+#include <isc/commandline.h>
+#include <isc/file.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>
+
+#if USE_PKCS11
+#include <pk11/result.h>
+#endif /* if USE_PKCS11 */
+
+#include <dns/keyvalues.h>
+#include <dns/name.h>
+#include <dns/result.h>
+
+#include <dst/dst.h>
+
+#include <confgen/os.h>
+
+#include "keygen.h"
+#include "util.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;
+bool verbose = 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] [-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\
+  -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] [keyname]\n\
+  -a alg:        algorithm (default hmac-sha256)\n\n",
+			progname);
+	}
+
+	exit(status);
+}
+
+int
+main(int argc, char **argv) {
+	isc_result_t result = ISC_R_SUCCESS;
+	bool show_final_mem = false;
+	bool quiet = false;
+	isc_buffer_t key_txtbuffer;
+	char key_txtsecret[256];
+	isc_mem_t *mctx = 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;
+
+#if USE_PKCS11
+	pk11_result_register();
+#endif /* if USE_PKCS11 */
+	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 = true;
+	} else if (PROGCMP("ddns-confgen")) {
+		progmode = progmode_confgen;
+	} else {
+		UNREACHABLE();
+	}
+
+	isc_commandline_errprint = 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 = true;
+			break;
+		case 'q':
+			if (progmode == progmode_confgen) {
+				quiet = true;
+			} else {
+				usage(1);
+			}
+			break;
+		case 'r':
+			fatal("The -r option has been deprecated.");
+			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);
+
+	isc_mem_create(&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);
+			snprintf(keybuf, len, "%s.%s", keyname, suffix);
+			keyname = (const char *)keybuf;
+		}
+	}
+
+	isc_buffer_init(&key_txtbuffer, &key_txtsecret, sizeof(key_txtsecret));
+
+	generate_key(mctx, 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);
+}