external/bsd/bind/dist/contrib/sdb/dir/dirdb.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (C) 2004, 2007  Internet Systems Consortium, Inc. ("ISC")
   5  * Copyright (C) 2000, 2001  Internet Software Consortium.
   6  *
   7  * Permission to use, copy, modify, and/or distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  12  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  13  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  14  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  15  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  16  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  17  * PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 /* Id: dirdb.c,v 1.12 2007/06/19 23:47:07 tbox Exp */
  21
  22 /*
  23  * A simple database driver that returns basic information about
  24  * files and directories in the Unix file system as DNS data.
  25  */
  26
  27 #include <config.h>
  28
  29 #include <stdio.h>
  30 #include <string.h>
  31 #include <unistd.h>
  32 #include <sys/stat.h>
  33 #include <sys/sysmacros.h>
  34
  35 #include <isc/mem.h>
  36 #include <isc/print.h>
  37 #include <isc/result.h>
  38 #include <isc/util.h>
  39
  40 #include <dns/sdb.h>
  41
  42 #include <named/globals.h>
  43
  44 #include "dirdb.h"
  45
  46 static dns_sdbimplementation_t *dirdb = NULL;
  47
  48 #define CHECK(op)                                               \
  49         do { result = (op);                                     \
  50                 if (result != ISC_R_SUCCESS) return (result);   \
  51         } while (0)
  52
  53 #define CHECKN(op)                                              \
  54         do { n = (op);                                          \
  55                 if (n < 0) return (ISC_R_FAILURE);              \
  56         } while (0)
  57
  58
  59 /*
  60  * This database operates on relative names.
  61  *
  62  * Any name will be interpreted as a pathname offset from the directory
  63  * specified in the configuration file.
  64  */
  65 static isc_result_t
  66 dirdb_lookup(const char *zone, const char *name, void *dbdata,
  67               dns_sdblookup_t *lookup)
  68 {
  69         char filename[255];
  70         char filename2[255];
  71         char buf[1024];
  72         struct stat statbuf;
  73         isc_result_t result;
  74         int n;
  75
  76         UNUSED(zone);
  77         UNUSED(dbdata);
  78
  79         if (strcmp(name, "@") == 0)
  80                 snprintf(filename, sizeof(filename), "%s", (char *)dbdata);
  81         else
  82                 snprintf(filename, sizeof(filename), "%s/%s",
  83                          (char *)dbdata, name);
  84         CHECKN(lstat(filename, &statbuf));
  85
  86         if (S_ISDIR(statbuf.st_mode))
  87                 CHECK(dns_sdb_putrr(lookup, "txt", 3600, "dir"));
  88         else if (S_ISCHR(statbuf.st_mode) || S_ISBLK(statbuf.st_mode)) {
  89                 CHECKN(snprintf(buf, sizeof(buf),
  90                                 "\"%sdev\" \"major %d\" \"minor %d\"",
  91                                 S_ISCHR(statbuf.st_mode) ? "chr" : "blk",
  92                                 major(statbuf.st_rdev),
  93                                 minor(statbuf.st_rdev)));
  94                 CHECK(dns_sdb_putrr(lookup, "txt", 3600, buf));
  95         } else if (S_ISFIFO(statbuf.st_mode))
  96                 CHECK(dns_sdb_putrr(lookup, "txt", 3600, "pipe"));
  97         else if (S_ISSOCK(statbuf.st_mode))
  98                 CHECK(dns_sdb_putrr(lookup, "txt", 3600, "socket"));
  99         else if (S_ISLNK(statbuf.st_mode)) {
 100                 CHECKN(readlink(filename, filename2, sizeof(filename2) - 1));
 101                 buf[n] = 0;
 102                 CHECKN(snprintf(buf, sizeof(buf), "\"symlink\" \"%s\"",
 103                                 filename2));
 104                 CHECK(dns_sdb_putrr(lookup, "txt", 3600, buf));
 105         } else if (!S_ISREG(statbuf.st_mode))
 106                 CHECK(dns_sdb_putrr(lookup, "txt", 3600, "unknown"));
 107         else {
 108                 CHECKN(snprintf(buf, sizeof(buf), "\"file\" \"size = %u\"",
 109                          (unsigned int)statbuf.st_size));
 110                 CHECK(dns_sdb_putrr(lookup, "txt", 3600, buf));
 111         }
 112
 113         return (ISC_R_SUCCESS);
 114 }
 115
 116 /*
 117  * lookup () does not return SOA or NS records, so authority() must be defined.
 118  */
 119 static isc_result_t
 120 dirdb_authority(const char *zone, void *dbdata, dns_sdblookup_t *lookup) {
 121         isc_result_t result;
 122
 123         UNUSED(zone);
 124         UNUSED(dbdata);
 125
 126         result = dns_sdb_putsoa(lookup, "ns", "hostmaster", 0);
 127         INSIST(result == ISC_R_SUCCESS);
 128         result = dns_sdb_putrr(lookup, "ns", 86400, "ns1");
 129         INSIST(result == ISC_R_SUCCESS);
 130         result = dns_sdb_putrr(lookup, "ns", 86400, "ns2");
 131         INSIST(result == ISC_R_SUCCESS);
 132         return (ISC_R_SUCCESS);
 133 }
 134
 135 /*
 136  * Each database stores the top-level directory as the dbdata opaque
 137  * object.  The create() function allocates it.  argv[0] holds the top
 138  * level directory.
 139  */
 140 static isc_result_t
 141 dirdb_create(const char *zone, int argc, char **argv,
 142              void *driverdata, void **dbdata)
 143 {
 144         UNUSED(zone);
 145         UNUSED(driverdata);
 146
 147         if (argc < 1)
 148                 return (ISC_R_FAILURE);
 149         *dbdata = isc_mem_strdup((isc_mem_t *)driverdata, argv[0]);
 150         if (*dbdata == NULL)
 151                 return (ISC_R_NOMEMORY);
 152         return (ISC_R_SUCCESS);
 153 }
 154
 155 /*
 156  * The destroy() function frees the memory allocated by create().
 157  */
 158 static void
 159 dirdb_destroy(const char *zone, void *driverdata, void **dbdata) {
 160         UNUSED(zone);
 161         UNUSED(driverdata);
 162         isc_mem_free((isc_mem_t *)driverdata, *dbdata);
 163 }
 164
 165 /*
 166  * This zone does not support zone transfer, so allnodes() is NULL.
 167  */
 168 static dns_sdbmethods_t dirdb_methods = {
 169         dirdb_lookup,
 170         dirdb_authority,
 171         NULL, /* allnodes */
 172         dirdb_create,
 173         dirdb_destroy
 174 };
 175
 176 /*
 177  * Wrapper around dns_sdb_register().  Note that the first ns_g_mctx is
 178  * being passed as the "driverdata" parameter, so that will it will be
 179  * passed to create() and destroy().
 180  */
 181 isc_result_t
 182 dirdb_init(void) {
 183         unsigned int flags;
 184         flags = DNS_SDBFLAG_RELATIVEOWNER | DNS_SDBFLAG_RELATIVERDATA |
 185                 DNS_SDBFLAG_THREADSAFE;
 186         return (dns_sdb_register("dir", &dirdb_methods, ns_g_mctx, flags,
 187                                  ns_g_mctx, &dirdb));
 188 }
 189
 190 /*
 191  * Wrapper around dns_sdb_unregister().
 192  */
 193 void
 194 dirdb_clear(void) {
 195         if (dirdb != NULL)
 196                 dns_sdb_unregister(&dirdb);
 197 }