external/bsd/bind/dist/bin/confgen/keygen.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (C) 2009  Internet Systems Consortium, Inc. ("ISC")
   5  *
   6  * Permission to use, copy, modify, and/or distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  11  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  12  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  13  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  14  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  15  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  16  * PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 /* Id: keygen.c,v 1.4 2009/11/12 14:02:38 marka Exp */
  20
  21 /*! \file */
  22
  23 #include <config.h>
  24
  25 #include <stdlib.h>
  26 #include <stdarg.h>
  27
  28 #include <isc/base64.h>
  29 #include <isc/buffer.h>
  30 #include <isc/entropy.h>
  31 #include <isc/file.h>
  32 #include <isc/keyboard.h>
  33 #include <isc/mem.h>
  34 #include <isc/result.h>
  35 #include <isc/string.h>
  36
  37 #include <dns/keyvalues.h>
  38 #include <dns/name.h>
  39
  40 #include <dst/dst.h>
  41 #include <confgen/os.h>
  42
  43 #include "util.h"
  44 #include "keygen.h"
  45
  46 /*%
  47  * Convert algorithm type to string.
  48  */
  49 const char *
  50 alg_totext(dns_secalg_t alg) {
  51         switch (alg) {
  52             case DST_ALG_HMACMD5:
  53                 return "hmac-md5";
  54             case DST_ALG_HMACSHA1:
  55                 return "hmac-sha1";
  56             case DST_ALG_HMACSHA224:
  57                 return "hmac-sha224";
  58             case DST_ALG_HMACSHA256:
  59                 return "hmac-sha256";
  60             case DST_ALG_HMACSHA384:
  61                 return "hmac-sha384";
  62             case DST_ALG_HMACSHA512:
  63                 return "hmac-sha512";
  64             default:
  65                 return "(unknown)";
  66         }
  67 }
  68
  69 /*%
  70  * Convert string to algorithm type.
  71  */
  72 dns_secalg_t
  73 alg_fromtext(const char *name) {
  74         if (strcmp(name, "hmac-md5") == 0)
  75                 return DST_ALG_HMACMD5;
  76         if (strcmp(name, "hmac-sha1") == 0)
  77                 return DST_ALG_HMACSHA1;
  78         if (strcmp(name, "hmac-sha224") == 0)
  79                 return DST_ALG_HMACSHA224;
  80         if (strcmp(name, "hmac-sha256") == 0)
  81                 return DST_ALG_HMACSHA256;
  82         if (strcmp(name, "hmac-sha384") == 0)
  83                 return DST_ALG_HMACSHA384;
  84         if (strcmp(name, "hmac-sha512") == 0)
  85                 return DST_ALG_HMACSHA512;
  86         return DST_ALG_UNKNOWN;
  87 }
  88
  89 /*%
  90  * Return default keysize for a given algorithm type.
  91  */
  92 int
  93 alg_bits(dns_secalg_t alg) {
  94         switch (alg) {
  95             case DST_ALG_HMACMD5:
  96                 return 128;
  97             case DST_ALG_HMACSHA1:
  98                 return 160;
  99             case DST_ALG_HMACSHA224:
 100                 return 224;
 101             case DST_ALG_HMACSHA256:
 102                 return 256;
 103             case DST_ALG_HMACSHA384:
 104                 return 384;
 105             case DST_ALG_HMACSHA512:
 106                 return 512;
 107             default:
 108                 return 0;
 109         }
 110 }
 111
 112 /*%
 113  * Generate a key of size 'keysize' using entropy source 'randomfile',
 114  * and place it in 'key_txtbuffer'
 115  */
 116 void
 117 generate_key(isc_mem_t *mctx, const char *randomfile, dns_secalg_t alg,
 118              int keysize, isc_buffer_t *key_txtbuffer) {
 119         isc_result_t result = ISC_R_SUCCESS;
 120         isc_entropysource_t *entropy_source = NULL;
 121         int open_keyboard = ISC_ENTROPY_KEYBOARDMAYBE;
 122         int entropy_flags = 0;
 123         isc_entropy_t *ectx = NULL;
 124         isc_buffer_t key_rawbuffer;
 125         isc_region_t key_rawregion;
 126         char key_rawsecret[64];
 127         dst_key_t *key = NULL;
 128
 129         switch (alg) {
 130             case DST_ALG_HMACMD5:
 131                 if (keysize < 1 || keysize > 512)
 132                         fatal("keysize %d out of range (must be 1-512)\n",
 133                               keysize);
 134                 break;
 135             case DST_ALG_HMACSHA256:
 136                 if (keysize < 1 || keysize > 256)
 137                         fatal("keysize %d out of range (must be 1-256)\n",
 138                               keysize);
 139                 break;
 140             default:
 141                 fatal("unsupported algorithm %d\n", alg);
 142         }
 143
 144
 145         DO("create entropy context", isc_entropy_create(mctx, &ectx));
 146
 147         if (randomfile != NULL && strcmp(randomfile, "keyboard") == 0) {
 148                 randomfile = NULL;
 149                 open_keyboard = ISC_ENTROPY_KEYBOARDYES;
 150         }
 151         DO("start entropy source", isc_entropy_usebestsource(ectx,
 152                                                              &entropy_source,
 153                                                              randomfile,
 154                                                              open_keyboard));
 155
 156         entropy_flags = ISC_ENTROPY_BLOCKING | ISC_ENTROPY_GOODONLY;
 157
 158         DO("initialize dst library", dst_lib_init(mctx, ectx, entropy_flags));
 159
 160         DO("generate key", dst_key_generate(dns_rootname, alg,
 161                                             keysize, 0, 0,
 162                                             DNS_KEYPROTO_ANY,
 163                                             dns_rdataclass_in, mctx, &key));
 164
 165         isc_buffer_init(&key_rawbuffer, &key_rawsecret, sizeof(key_rawsecret));
 166
 167         DO("dump key to buffer", dst_key_tobuffer(key, &key_rawbuffer));
 168
 169         isc_buffer_usedregion(&key_rawbuffer, &key_rawregion);
 170
 171         DO("bsse64 encode secret", isc_base64_totext(&key_rawregion, -1, "",
 172                                                      key_txtbuffer));
 173
 174         /*
 175          * Shut down the entropy source now so the "stop typing" message
 176          * does not muck with the output.
 177          */
 178         if (entropy_source != NULL)
 179                 isc_entropy_destroysource(&entropy_source);
 180
 181         if (key != NULL)
 182                 dst_key_free(&key);
 183
 184         isc_entropy_detach(&ectx);
 185         dst_lib_destroy();
 186 }
 187
 188 /*%
 189  * Write a key file to 'keyfile'.  If 'user' is non-NULL,
 190  * make that user the owner of the file.  The key will have
 191  * the name 'keyname' and the secret in the buffer 'secret'.
 192  */
 193 void
 194 write_key_file(const char *keyfile, const char *user,
 195                const char *keyname, isc_buffer_t *secret,
 196                dns_secalg_t alg) {
 197         isc_result_t result;
 198         const char *algname = alg_totext(alg);
 199         FILE *fd = NULL;
 200
 201         DO("create keyfile", isc_file_safecreate(keyfile, &fd));
 202
 203         if (user != NULL) {
 204                 if (set_user(fd, user) == -1)
 205                         fatal("unable to set file owner\n");
 206         }
 207
 208         fprintf(fd, "key \"%s\" {\n\talgorithm %s;\n"
 209                 "\tsecret \"%.*s\";\n};\n",
 210                 keyname, algname,
 211                 (int)isc_buffer_usedlength(secret),
 212                 (char *)isc_buffer_base(secret));
 213         fflush(fd);
 214         if (ferror(fd))
 215                 fatal("write to %s failed\n", keyfile);
 216         if (fclose(fd))
 217                 fatal("fclose(%s) failed\n", keyfile);
 218         fprintf(stderr, "wrote key file \"%s\"\n", keyfile);
 219 }
 220