source/utils/net_dns.c

   1
   2 /*
   3    Samba Unix/Linux Dynamic DNS Update
   4    net ads commands
   5
   6    Copyright (C) Krishna Ganugapati (krishnag@centeris.com)         2006
   7    Copyright (C) Gerald Carter                                      2006
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 #include "includes.h"
  24 #include "utils/net.h"
  25 #include "dns.h"
  26
  27 #if defined(WITH_DNS_UPDATES)
  28
  29 /*
  30  * Silly prototype to get rid of a warning
  31  */
  32
  33 DNS_ERROR DoDNSUpdate(char *pszServerName,
  34                       const char *pszDomainName, const char *pszHostName,
  35                       const struct sockaddr_storage *sslist,
  36                       size_t num_addrs );
  37
  38 /*********************************************************************
  39 *********************************************************************/
  40
  41 DNS_ERROR DoDNSUpdate(char *pszServerName,
  42                       const char *pszDomainName, const char *pszHostName,
  43                       const struct sockaddr_storage *sslist, size_t num_addrs )
  44 {
  45         DNS_ERROR err;
  46         struct dns_connection *conn;
  47         TALLOC_CTX *mem_ctx;
  48         OM_uint32 minor;
  49         struct dns_update_request *req, *resp;
  50
  51         if ( (num_addrs <= 0) || !sslist ) {
  52                 return ERROR_DNS_INVALID_PARAMETER;
  53         }
  54
  55         if (!(mem_ctx = talloc_init("DoDNSUpdate"))) {
  56                 return ERROR_DNS_NO_MEMORY;
  57         }
  58
  59         err = dns_open_connection( pszServerName, DNS_TCP, mem_ctx, &conn );
  60         if (!ERR_DNS_IS_OK(err)) {
  61                 goto error;
  62         }
  63
  64         /*
  65          * Probe if everything's fine
  66          */
  67
  68         err = dns_create_probe(mem_ctx, pszDomainName, pszHostName,
  69                                num_addrs, sslist, &req);
  70         if (!ERR_DNS_IS_OK(err)) goto error;
  71
  72         err = dns_update_transaction(mem_ctx, conn, req, &resp);
  73         if (!ERR_DNS_IS_OK(err)) goto error;
  74
  75         if (dns_response_code(resp->flags) == DNS_NO_ERROR) {
  76                 TALLOC_FREE(mem_ctx);
  77                 return ERROR_DNS_SUCCESS;
  78         }
  79
  80         /*
  81          * First try without signing
  82          */
  83
  84         err = dns_create_update_request(mem_ctx, pszDomainName, pszHostName,
  85                                         sslist, num_addrs, &req);
  86         if (!ERR_DNS_IS_OK(err)) goto error;
  87
  88         err = dns_update_transaction(mem_ctx, conn, req, &resp);
  89         if (!ERR_DNS_IS_OK(err)) goto error;
  90
  91         if (dns_response_code(resp->flags) == DNS_NO_ERROR) {
  92                 TALLOC_FREE(mem_ctx);
  93                 return ERROR_DNS_SUCCESS;
  94         }
  95
  96         /*
  97          * Okay, we have to try with signing
  98          */
  99         {
 100                 gss_ctx_id_t gss_context;
 101                 char *keyname;
 102
 103                 if (!(keyname = dns_generate_keyname( mem_ctx ))) {
 104                         err = ERROR_DNS_NO_MEMORY;
 105                         goto error;
 106                 }
 107
 108                 err = dns_negotiate_sec_ctx( pszDomainName, pszServerName,
 109                                              keyname, &gss_context, DNS_SRV_ANY );
 110
 111                 /* retry using the Windows 2000 DNS hack */
 112                 if (!ERR_DNS_IS_OK(err)) {
 113                         err = dns_negotiate_sec_ctx( pszDomainName, pszServerName,
 114                                                      keyname, &gss_context,
 115                                                      DNS_SRV_WIN2000 );
 116                 }
 117
 118                 if (!ERR_DNS_IS_OK(err))
 119                         goto error;
 120
 121
 122                 err = dns_sign_update(req, gss_context, keyname,
 123                                       "gss.microsoft.com", time(NULL), 3600);
 124
 125                 gss_delete_sec_context(&minor, &gss_context, GSS_C_NO_BUFFER);
 126
 127                 if (!ERR_DNS_IS_OK(err)) goto error;
 128
 129                 err = dns_update_transaction(mem_ctx, conn, req, &resp);
 130                 if (!ERR_DNS_IS_OK(err)) goto error;
 131
 132                 err = (dns_response_code(resp->flags) == DNS_NO_ERROR) ?
 133                         ERROR_DNS_SUCCESS : ERROR_DNS_UPDATE_FAILED;
 134         }
 135
 136
 137 error:
 138         TALLOC_FREE(mem_ctx);
 139         return err;
 140 }
 141
 142 /*********************************************************************
 143 *********************************************************************/
 144
 145 int get_my_ip_address( struct sockaddr_storage **pp_ss )
 146
 147 {
 148         int i, n;
 149         struct sockaddr_storage *list = NULL;
 150         int count = 0;
 151
 152         /* Honor the configured list of interfaces to register */
 153
 154         load_interfaces();
 155         n = iface_count();
 156
 157         if (n <= 0) {
 158                 return -1;
 159         }
 160
 161         if ( (list = SMB_MALLOC_ARRAY( struct sockaddr_storage, n )) == NULL ) {
 162                 return -1;
 163         }
 164
 165         for ( i=0; i<n; i++ ) {
 166                 const struct sockaddr_storage *nic_sa_storage = NULL;
 167
 168                 if ((nic_sa_storage = iface_n_sockaddr_storage(i)) == NULL)
 169                         continue;
 170
 171                 /* Don't register loopback addresses */
 172                 if (is_loopback_addr(nic_sa_storage)) {
 173                         continue;
 174                 }
 175
 176                 memcpy(&list[count++], nic_sa_storage, sizeof(struct sockaddr_storage));
 177         }
 178         *pp_ss = list;
 179
 180         return count;
 181 }
 182
 183 /*
 184  * Silly prototype to get rid of a warning
 185  */
 186
 187 DNS_ERROR do_gethostbyname(const char *server, const char *host);
 188
 189 DNS_ERROR do_gethostbyname(const char *server, const char *host)
 190 {
 191         struct dns_connection *conn;
 192         struct dns_request *req, *resp;
 193         DNS_ERROR err;
 194
 195         err = dns_open_connection(server, DNS_UDP, NULL, &conn);
 196         if (!ERR_DNS_IS_OK(err)) goto error;
 197
 198         err = dns_create_query(conn, host, QTYPE_A, DNS_CLASS_IN, &req);
 199         if (!ERR_DNS_IS_OK(err)) goto error;
 200
 201         err = dns_transaction(conn, conn, req, &resp);
 202
 203  error:
 204         TALLOC_FREE(conn);
 205         return err;
 206 }
 207
 208 #endif  /* defined(WITH_DNS_UPDATES) */