source3/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 2 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, write to the Free Software
  21    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22 */
  23
  24 #include "includes.h"
  25 #include "utils/net.h"
  26 #include "dns.h"
  27
  28 #if defined(WITH_DNS_UPDATES)
  29
  30 /*********************************************************************
  31 *********************************************************************/
  32
  33 DNS_ERROR DoDNSUpdate(ADS_STRUCT *ads, char *pszServerName,
  34                       const char *pszDomainName, const char *pszHostName,
  35                       const struct in_addr *iplist, int num_addrs )
  36 {
  37         DNS_ERROR err;
  38         struct dns_connection *conn;
  39         TALLOC_CTX *mem_ctx;
  40         OM_uint32 minor;
  41         struct dns_update_request *req, *resp;
  42
  43         if ( (num_addrs <= 0) || !iplist ) {
  44                 return ERROR_DNS_INVALID_PARAMETER;
  45         }
  46
  47         if (!(mem_ctx = talloc_init("DoDNSUpdate"))) {
  48                 return ERROR_DNS_NO_MEMORY;
  49         }
  50
  51         err = dns_open( pszServerName, DNS_TCP, mem_ctx, &conn );
  52         if (!ERR_DNS_IS_OK(err)) {
  53                 goto error;
  54         }
  55
  56         /*
  57          * Probe if everything's fine
  58          */
  59
  60         err = dns_create_probe(mem_ctx, pszDomainName, pszHostName,
  61                                num_addrs, iplist, &req);
  62         if (!ERR_DNS_IS_OK(err)) goto error;
  63
  64         err = dns_update_transaction(mem_ctx, conn, req, &resp);
  65         if (!ERR_DNS_IS_OK(err)) goto error;
  66
  67         if (dns_response_code(resp->flags) == DNS_NO_ERROR) {
  68                 TALLOC_FREE(mem_ctx);
  69                 return ERROR_DNS_SUCCESS;
  70         }
  71
  72         /*
  73          * First try without signing
  74          */
  75
  76         err = dns_create_update_request(mem_ctx, pszDomainName, pszHostName,
  77                                         iplist[0].s_addr, &req);
  78         if (!ERR_DNS_IS_OK(err)) goto error;
  79
  80         err = dns_update_transaction(mem_ctx, conn, req, &resp);
  81         if (!ERR_DNS_IS_OK(err)) goto error;
  82
  83         if (dns_response_code(resp->flags) == DNS_NO_ERROR) {
  84                 TALLOC_FREE(mem_ctx);
  85                 return ERROR_DNS_SUCCESS;
  86         }
  87
  88         /*
  89          * Okay, we have to try with signing
  90          */
  91         {
  92                 ADS_STRUCT *ads_s;
  93                 gss_ctx_id_t gss_context;
  94                 int res;
  95                 char *keyname;
  96
  97                 if (!(keyname = dns_generate_keyname( mem_ctx ))) {
  98                         err = ERROR_DNS_NO_MEMORY;
  99                         goto error;
 100                 }
 101
 102                 if (!(ads_s = ads_init(ads->server.realm, ads->server.workgroup,
 103                                        ads->server.ldap_server))) {
 104                         return ERROR_DNS_NO_MEMORY;
 105                 }
 106
 107                 /* kinit with the machine password */
 108                 setenv(KRB5_ENV_CCNAME, "MEMORY:net_ads", 1);
 109                 asprintf( &ads_s->auth.user_name, "%s$", global_myname() );
 110                 ads_s->auth.password = secrets_fetch_machine_password(
 111                         lp_workgroup(), NULL, NULL );
 112                 ads_s->auth.realm = SMB_STRDUP( lp_realm() );
 113                 res = ads_kinit_password( ads_s );
 114                 ads_destroy(&ads_s);
 115                 if (res) {
 116                         err = ERROR_DNS_GSS_ERROR;
 117                         goto error;
 118                 }
 119
 120                 err = dns_negotiate_sec_ctx( pszDomainName, pszServerName,
 121                                              keyname, &gss_context );
 122                 if (!ERR_DNS_IS_OK(err)) goto error;
 123
 124                 err = dns_sign_update(req, gss_context, keyname,
 125                                       "gss.microsoft.com", time(NULL), 3600);
 126
 127                 gss_delete_sec_context(&minor, &gss_context, GSS_C_NO_BUFFER);
 128
 129                 if (!ERR_DNS_IS_OK(err)) goto error;
 130
 131                 err = dns_update_transaction(mem_ctx, conn, req, &resp);
 132                 if (!ERR_DNS_IS_OK(err)) goto error;
 133
 134                 err = (dns_response_code(resp->flags) == DNS_NO_ERROR) ?
 135                         ERROR_DNS_SUCCESS : ERROR_DNS_UPDATE_FAILED;
 136         }
 137
 138
 139 error:
 140         TALLOC_FREE(mem_ctx);
 141         return err;
 142 }
 143
 144 /*********************************************************************
 145 *********************************************************************/
 146
 147 int get_my_ip_address( struct in_addr **ips )
 148 {
 149         struct iface_struct nics[MAX_INTERFACES];
 150         int i, n;
 151         struct in_addr loopback_ip = *interpret_addr2("127.0.0.1");
 152         struct in_addr *list;
 153         int count = 0;
 154
 155         /* find the first non-loopback address from our list of interfaces */
 156
 157         n = get_interfaces(nics, MAX_INTERFACES);
 158
 159         if ( (list = SMB_MALLOC_ARRAY( struct in_addr, n )) == NULL ) {
 160                 return -1;
 161         }
 162
 163         for ( i=0; i<n; i++ ) {
 164                 if ( nics[i].ip.s_addr != loopback_ip.s_addr ) {
 165                         memcpy( &list[count++], &nics[i].ip, sizeof( struct in_addr ) );
 166                 }
 167         }
 168         *ips = list;
 169
 170         return count;
 171 }
 172
 173 DNS_ERROR do_gethostbyname(const char *server, const char *host)
 174 {
 175         struct dns_connection *conn;
 176         struct dns_request *req, *resp;
 177         DNS_ERROR err;
 178
 179         err = dns_open(server, DNS_UDP, NULL, &conn);
 180         if (!ERR_DNS_IS_OK(err)) goto error;
 181
 182         err = dns_create_query(conn, host, QTYPE_A, DNS_CLASS_IN, &req);
 183         if (!ERR_DNS_IS_OK(err)) goto error;
 184
 185         err = dns_transaction(conn, conn, req, &resp);
 186
 187  error:
 188         TALLOC_FREE(conn);
 189         return err;
 190 }
 191
 192 #endif  /* defined(WITH_DNS_UPDATES) */