source3/lib/messages_ctdbd.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Samba internal messaging functions
   4    Copyright (C) 2007 by Volker Lendecke
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "includes.h"
  21 #include "messages.h"
  22 #include "util_tdb.h"
  23 #include "lib/util/iov_buf.h"
  24
  25 #include "ctdb.h"
  26 #include "ctdb_private.h"
  27 #include "ctdbd_conn.h"
  28
  29
  30 struct messaging_ctdbd_context {
  31         struct ctdbd_connection *conn;
  32 };
  33
  34 /*
  35  * This is a Samba3 hack/optimization. Routines like process_exists need to
  36  * talk to ctdbd, and they don't get handed a messaging context.
  37  */
  38 static struct ctdbd_connection *global_ctdbd_connection;
  39 static int global_ctdb_connection_pid;
  40
  41 struct ctdbd_connection *messaging_ctdbd_connection(void)
  42 {
  43         if (!lp_clustering()) {
  44                 return NULL;
  45         }
  46
  47         if (global_ctdb_connection_pid == 0 &&
  48             global_ctdbd_connection == NULL) {
  49                 struct tevent_context *ev;
  50                 struct messaging_context *msg;
  51
  52                 ev = samba_tevent_context_init(NULL);
  53                 if (!ev) {
  54                         DEBUG(0,("samba_tevent_context_init failed\n"));
  55                 }
  56
  57                 msg = messaging_init(NULL, ev);
  58                 if (!msg) {
  59                         DEBUG(0,("messaging_init failed\n"));
  60                         return NULL;
  61                 }
  62         }
  63
  64         if (global_ctdb_connection_pid != getpid()) {
  65                 DEBUG(0,("messaging_ctdbd_connection():"
  66                          "valid for pid[%jd] but it's [%jd]\n",
  67                          (intmax_t)global_ctdb_connection_pid,
  68                          (intmax_t)getpid()));
  69                 smb_panic("messaging_ctdbd_connection() invalid process\n");
  70         }
  71
  72         return global_ctdbd_connection;
  73 }
  74
  75 static int messaging_ctdb_send(struct server_id src,
  76                                struct server_id pid, int msg_type,
  77                                const struct iovec *iov, int iovlen,
  78                                const int *fds, size_t num_fds,
  79                                struct messaging_backend *backend)
  80 {
  81         struct messaging_ctdbd_context *ctx = talloc_get_type_abort(
  82                 backend->private_data, struct messaging_ctdbd_context);
  83         struct messaging_rec msg;
  84         uint8_t *buf;
  85         ssize_t buflen;
  86         NTSTATUS status;
  87
  88         if (num_fds > 0) {
  89                 return ENOSYS;
  90         }
  91
  92         buflen = iov_buflen(iov, iovlen);
  93         if (buflen == -1) {
  94                 return EMSGSIZE;
  95         }
  96
  97         buf = talloc_array(talloc_tos(), uint8_t, buflen);
  98         if (buf == NULL) {
  99                 return ENOMEM;
 100         }
 101         iov_buf(iov, iovlen, buf, buflen);
 102
 103         msg = (struct messaging_rec) {
 104                 .msg_version    = MESSAGE_VERSION,
 105                 .msg_type       = msg_type,
 106                 .dest           = pid,
 107                 .src            = src,
 108                 .buf            = data_blob_const(buf, talloc_get_size(buf)),
 109         };
 110
 111         status = ctdbd_messaging_send(ctx->conn, pid.vnn, pid.pid, &msg);
 112
 113         TALLOC_FREE(buf);
 114
 115         if (NT_STATUS_IS_OK(status)) {
 116                 return 0;
 117         }
 118         return map_errno_from_nt_status(status);
 119 }
 120
 121 static int messaging_ctdbd_destructor(struct messaging_ctdbd_context *ctx)
 122 {
 123         /*
 124          * The global connection just went away
 125          */
 126         global_ctdb_connection_pid = 0;
 127         global_ctdbd_connection = NULL;
 128         return 0;
 129 }
 130
 131 NTSTATUS messaging_ctdbd_init(struct messaging_context *msg_ctx,
 132                               TALLOC_CTX *mem_ctx,
 133                               struct messaging_backend **presult)
 134 {
 135         struct messaging_backend *result;
 136         struct messaging_ctdbd_context *ctx;
 137         NTSTATUS status;
 138
 139         if (!(result = talloc(mem_ctx, struct messaging_backend))) {
 140                 DEBUG(0, ("talloc failed\n"));
 141                 return NT_STATUS_NO_MEMORY;
 142         }
 143
 144         if (!(ctx = talloc(result, struct messaging_ctdbd_context))) {
 145                 DEBUG(0, ("talloc failed\n"));
 146                 TALLOC_FREE(result);
 147                 return NT_STATUS_NO_MEMORY;
 148         }
 149
 150         status = ctdbd_messaging_connection(ctx, &ctx->conn);
 151
 152         if (!NT_STATUS_IS_OK(status)) {
 153                 DEBUG(10, ("ctdbd_messaging_connection failed: %s\n",
 154                            nt_errstr(status)));
 155                 TALLOC_FREE(result);
 156                 return status;
 157         }
 158
 159         status = ctdbd_register_msg_ctx(ctx->conn, msg_ctx);
 160
 161         if (!NT_STATUS_IS_OK(status)) {
 162                 DEBUG(10, ("ctdbd_register_msg_ctx failed: %s\n",
 163                            nt_errstr(status)));
 164                 TALLOC_FREE(result);
 165                 return status;
 166         }
 167
 168         global_ctdb_connection_pid = getpid();
 169         global_ctdbd_connection = ctx->conn;
 170         talloc_set_destructor(ctx, messaging_ctdbd_destructor);
 171
 172         set_my_vnn(ctdbd_vnn(ctx->conn));
 173
 174         result->send_fn = messaging_ctdb_send;
 175         result->private_data = (void *)ctx;
 176
 177         *presult = result;
 178         return NT_STATUS_OK;
 179 }