contrib/bind9/bin/rndc/rndc-confgen.c

   1 /*
   2  * Copyright (C) 2004, 2005  Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (C) 2001, 2003  Internet Software Consortium.
   4  *
   5  * Permission to use, copy, modify, and distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  15  * PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 /* $Id: rndc-confgen.c,v 1.18.18.3 2005/04/29 00:15:40 marka Exp $ */
  19
  20 /*! \file */
  21
  22 /**
  23  * rndc-confgen generates configuration files for rndc. It can be used
  24  * as a convenient alternative to writing the rndc.conf file and the
  25  * corresponding controls and key statements in named.conf by hand.
  26  * Alternatively, it can be run with the -a option to set up a
  27  * rndc.key file and avoid the need for a rndc.conf file and a
  28  * controls statement altogether.
  29  */
  30
  31 #include <config.h>
  32
  33 #include <stdlib.h>
  34 #include <stdarg.h>
  35
  36 #include <isc/assertions.h>
  37 #include <isc/base64.h>
  38 #include <isc/buffer.h>
  39 #include <isc/commandline.h>
  40 #include <isc/entropy.h>
  41 #include <isc/file.h>
  42 #include <isc/keyboard.h>
  43 #include <isc/mem.h>
  44 #include <isc/net.h>
  45 #include <isc/print.h>
  46 #include <isc/result.h>
  47 #include <isc/string.h>
  48 #include <isc/time.h>
  49 #include <isc/util.h>
  50
  51 #include <dns/keyvalues.h>
  52 #include <dns/name.h>
  53
  54 #include <dst/dst.h>
  55 #include <rndc/os.h>
  56
  57 #include "util.h"
  58
  59 #define DEFAULT_KEYLENGTH       128             /*% Bits. */
  60 #define DEFAULT_KEYNAME         "rndc-key"
  61 #define DEFAULT_SERVER          "127.0.0.1"
  62 #define DEFAULT_PORT            953
  63
  64 static char program[256];
  65 char *progname;
  66
  67 isc_boolean_t verbose = ISC_FALSE;
  68
  69 const char *keyfile, *keydef;
  70
  71 static void
  72 usage(int status) {
  73
  74         fprintf(stderr, "\
  75 Usage:\n\
  76  %s [-a] [-b bits] [-c keyfile] [-k keyname] [-p port] [-r randomfile] \
  77 [-s addr] [-t chrootdir] [-u user]\n\
  78   -a:           generate just the key clause and write it to keyfile (%s)\n\
  79   -b bits:      from 1 through 512, default %d; total length of the secret\n\
  80   -c keyfile:   specify an alternate key file (requires -a)\n\
  81   -k keyname:   the name as it will be used  in named.conf and rndc.conf\n\
  82   -p port:      the port named will listen on and rndc will connect to\n\
  83   -r randomfile: a file containing random data\n\
  84   -s addr:      the address to which rndc should connect\n\
  85   -t chrootdir: write a keyfile in chrootdir as well (requires -a)\n\
  86   -u user:      set the keyfile owner to \"user\" (requires -a)\n",
  87                 progname, keydef, DEFAULT_KEYLENGTH);
  88
  89         exit (status);
  90 }
  91
  92 /*%
  93  * Write an rndc.key file to 'keyfile'.  If 'user' is non-NULL,
  94  * make that user the owner of the file.  The key will have
  95  * the name 'keyname' and the secret in the buffer 'secret'.
  96  */
  97 static void
  98 write_key_file(const char *keyfile, const char *user,
  99                const char *keyname, isc_buffer_t *secret )
 100 {
 101         FILE *fd;
 102
 103         fd = safe_create(keyfile);
 104         if (fd == NULL)
 105                 fatal( "unable to create \"%s\"\n", keyfile);
 106         if (user != NULL) {
 107                 if (set_user(fd, user) == -1)
 108                         fatal("unable to set file owner\n");
 109         }
 110         fprintf(fd, "key \"%s\" {\n\talgorithm hmac-md5;\n"
 111                 "\tsecret \"%.*s\";\n};\n", keyname,
 112                 (int)isc_buffer_usedlength(secret),
 113                 (char *)isc_buffer_base(secret));
 114         fflush(fd);
 115         if (ferror(fd))
 116                 fatal("write to %s failed\n", keyfile);
 117         if (fclose(fd))
 118                 fatal("fclose(%s) failed\n", keyfile);
 119         fprintf(stderr, "wrote key file \"%s\"\n", keyfile);
 120 }
 121
 122 int
 123 main(int argc, char **argv) {
 124         isc_boolean_t show_final_mem = ISC_FALSE;
 125         isc_buffer_t key_rawbuffer;
 126         isc_buffer_t key_txtbuffer;
 127         isc_region_t key_rawregion;
 128         isc_mem_t *mctx = NULL;
 129         isc_entropy_t *ectx = NULL;
 130         isc_entropysource_t *entropy_source = NULL;
 131         isc_result_t result = ISC_R_SUCCESS;
 132         dst_key_t *key = NULL;
 133         const char *keyname = NULL;
 134         const char *randomfile = NULL;
 135         const char *serveraddr = NULL;
 136         char key_rawsecret[64];
 137         char key_txtsecret[256];
 138         char *p;
 139         int ch;
 140         int port;
 141         int keysize;
 142         int entropy_flags = 0;
 143         int open_keyboard = ISC_ENTROPY_KEYBOARDMAYBE;
 144         struct in_addr addr4_dummy;
 145         struct in6_addr addr6_dummy;
 146         char *chrootdir = NULL;
 147         char *user = NULL;
 148         isc_boolean_t keyonly = ISC_FALSE;
 149         int len;
 150
 151         keydef = keyfile = RNDC_KEYFILE;
 152
 153         result = isc_file_progname(*argv, program, sizeof(program));
 154         if (result != ISC_R_SUCCESS)
 155                 memcpy(program, "rndc-confgen", 13);
 156         progname = program;
 157
 158         keyname = DEFAULT_KEYNAME;
 159         keysize = DEFAULT_KEYLENGTH;
 160         serveraddr = DEFAULT_SERVER;
 161         port = DEFAULT_PORT;
 162
 163         while ((ch = isc_commandline_parse(argc, argv,
 164                                            "ab:c:hk:Mmp:r:s:t:u:Vy")) != -1) {
 165                 switch (ch) {
 166                 case 'a':
 167                         keyonly = ISC_TRUE;
 168                         break;
 169                 case 'b':
 170                         keysize = strtol(isc_commandline_argument, &p, 10);
 171                         if (*p != '\0' || keysize < 0)
 172                                 fatal("-b requires a non-negative number");
 173                         if (keysize < 1 || keysize > 512)
 174                                 fatal("-b must be in the range 1 through 512");
 175                         break;
 176                 case 'c':
 177                         keyfile = isc_commandline_argument;
 178                         break;
 179                 case 'h':
 180                         usage(0);
 181                 case 'k':
 182                 case 'y':       /* Compatible with rndc -y. */
 183                         keyname = isc_commandline_argument;
 184                         break;
 185                 case 'M':
 186                         isc_mem_debugging = ISC_MEM_DEBUGTRACE;
 187                         break;
 188
 189                 case 'm':
 190                         show_final_mem = ISC_TRUE;
 191                         break;
 192                 case 'p':
 193                         port = strtol(isc_commandline_argument, &p, 10);
 194                         if (*p != '\0' || port < 0 || port > 65535)
 195                                 fatal("port '%s' out of range",
 196                                       isc_commandline_argument);
 197                         break;
 198                 case 'r':
 199                         randomfile = isc_commandline_argument;
 200                         break;
 201                 case 's':
 202                         serveraddr = isc_commandline_argument;
 203                         if (inet_pton(AF_INET, serveraddr, &addr4_dummy) != 1 &&
 204                             inet_pton(AF_INET6, serveraddr, &addr6_dummy) != 1)
 205                                 fatal("-s should be an IPv4 or IPv6 address");
 206                         break;
 207                 case 't':
 208                         chrootdir = isc_commandline_argument;
 209                         break;
 210                 case 'u':
 211                         user = isc_commandline_argument;
 212                         break;
 213                 case 'V':
 214                         verbose = ISC_TRUE;
 215                         break;
 216                 case '?':
 217                         usage(1);
 218                         break;
 219                 default:
 220                         fatal("unexpected error parsing command arguments: "
 221                               "got %c\n", ch);
 222                         break;
 223                 }
 224         }
 225
 226         argc -= isc_commandline_index;
 227         argv += isc_commandline_index;
 228
 229         if (argc > 0)
 230                 usage(1);
 231
 232         DO("create memory context", isc_mem_create(0, 0, &mctx));
 233
 234         DO("create entropy context", isc_entropy_create(mctx, &ectx));
 235
 236         if (randomfile != NULL && strcmp(randomfile, "keyboard") == 0) {
 237                 randomfile = NULL;
 238                 open_keyboard = ISC_ENTROPY_KEYBOARDYES;
 239         }
 240         DO("start entropy source", isc_entropy_usebestsource(ectx,
 241                                                              &entropy_source,
 242                                                              randomfile,
 243                                                              open_keyboard));
 244
 245         entropy_flags = ISC_ENTROPY_BLOCKING | ISC_ENTROPY_GOODONLY;
 246
 247         DO("initialize dst library", dst_lib_init(mctx, ectx, entropy_flags));
 248
 249         DO("generate key", dst_key_generate(dns_rootname, DST_ALG_HMACMD5,
 250                                             keysize, 0, 0,
 251                                             DNS_KEYPROTO_ANY,
 252                                             dns_rdataclass_in, mctx, &key));
 253
 254         isc_buffer_init(&key_rawbuffer, &key_rawsecret, sizeof(key_rawsecret));
 255
 256         DO("dump key to buffer", dst_key_tobuffer(key, &key_rawbuffer));
 257
 258         isc_buffer_init(&key_txtbuffer, &key_txtsecret, sizeof(key_txtsecret));
 259         isc_buffer_usedregion(&key_rawbuffer, &key_rawregion);
 260
 261         DO("bsse64 encode secret", isc_base64_totext(&key_rawregion, -1, "",
 262                                                      &key_txtbuffer));
 263
 264         /*
 265          * Shut down the entropy source now so the "stop typing" message
 266          * does not muck with the output.
 267          */
 268         if (entropy_source != NULL)
 269                 isc_entropy_destroysource(&entropy_source);
 270
 271         if (key != NULL)
 272                 dst_key_free(&key);
 273
 274         isc_entropy_detach(&ectx);
 275         dst_lib_destroy();
 276
 277         if (keyonly) {
 278                 write_key_file(keyfile, chrootdir == NULL ? user : NULL,
 279                                keyname, &key_txtbuffer);
 280
 281                 if (chrootdir != NULL) {
 282                         char *buf;
 283                         len = strlen(chrootdir) + strlen(keyfile) + 2;
 284                         buf = isc_mem_get(mctx, len);
 285                         if (buf == NULL)
 286                                 fatal("isc_mem_get(%d) failed\n", len);
 287                         snprintf(buf, len, "%s%s%s", chrootdir,
 288                                  (*keyfile != '/') ? "/" : "", keyfile);
 289
 290                         write_key_file(buf, user, keyname, &key_txtbuffer);
 291                         isc_mem_put(mctx, buf, len);
 292                 }
 293         } else {
 294                 printf("\
 295 # Start of rndc.conf\n\
 296 key \"%s\" {\n\
 297         algorithm hmac-md5;\n\
 298         secret \"%.*s\";\n\
 299 };\n\
 300 \n\
 301 options {\n\
 302         default-key \"%s\";\n\
 303         default-server %s;\n\
 304         default-port %d;\n\
 305 };\n\
 306 # End of rndc.conf\n\
 307 \n\
 308 # Use with the following in named.conf, adjusting the allow list as needed:\n\
 309 # key \"%s\" {\n\
 310 #       algorithm hmac-md5;\n\
 311 #       secret \"%.*s\";\n\
 312 # };\n\
 313 # \n\
 314 # controls {\n\
 315 #       inet %s port %d\n\
 316 #               allow { %s; } keys { \"%s\"; };\n\
 317 # };\n\
 318 # End of named.conf\n",
 319                        keyname,
 320                        (int)isc_buffer_usedlength(&key_txtbuffer),
 321                        (char *)isc_buffer_base(&key_txtbuffer),
 322                        keyname, serveraddr, port,
 323                        keyname,
 324                        (int)isc_buffer_usedlength(&key_txtbuffer),
 325                        (char *)isc_buffer_base(&key_txtbuffer),
 326                        serveraddr, port, serveraddr, keyname);
 327         }
 328
 329         if (show_final_mem)
 330                 isc_mem_stats(mctx, stderr);
 331
 332         isc_mem_destroy(&mctx);
 333
 334         return (0);
 335 }