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 #include "lib/messages_util.h"
  25 #include "ctdbd_conn.h"
  26
  27
  28 struct messaging_ctdbd_context {
  29         struct ctdbd_connection *conn;
  30 };
  31
  32 /*
  33  * This is a Samba3 hack/optimization. Routines like process_exists need to
  34  * talk to ctdbd, and they don't get handed a messaging context.
  35  */
  36 static struct ctdbd_connection *global_ctdbd_connection;
  37 static int global_ctdb_connection_pid;
  38
  39 struct ctdbd_connection *messaging_ctdbd_connection(void)
  40 {
  41         if (!lp_clustering()) {
  42                 return NULL;
  43         }
  44
  45         if (global_ctdb_connection_pid == 0 &&
  46             global_ctdbd_connection == NULL) {
  47                 struct tevent_context *ev;
  48                 struct messaging_context *msg;
  49
  50                 ev = samba_tevent_context_init(NULL);
  51                 if (!ev) {
  52                         DEBUG(0,("samba_tevent_context_init failed\n"));
  53                 }
  54
  55                 msg = messaging_init(NULL, ev);
  56                 if (!msg) {
  57                         DEBUG(0,("messaging_init failed\n"));
  58                         return NULL;
  59                 }
  60         }
  61
  62         if (global_ctdb_connection_pid != getpid()) {
  63                 DEBUG(0,("messaging_ctdbd_connection():"
  64                          "valid for pid[%jd] but it's [%jd]\n",
  65                          (intmax_t)global_ctdb_connection_pid,
  66                          (intmax_t)getpid()));
  67                 smb_panic("messaging_ctdbd_connection() invalid process\n");
  68         }
  69
  70         return global_ctdbd_connection;
  71 }
  72
  73 static int messaging_ctdb_send(struct server_id src,
  74                                struct server_id pid, int msg_type,
  75                                const struct iovec *iov, int iovlen,
  76                                const int *fds, size_t num_fds,
  77                                struct messaging_backend *backend)
  78 {
  79         struct messaging_ctdbd_context *ctx = talloc_get_type_abort(
  80                 backend->private_data, struct messaging_ctdbd_context);
  81         uint8_t hdr[MESSAGE_HDR_LENGTH];
  82         struct iovec iov2[iovlen+1];
  83         NTSTATUS status;
  84
  85         if (num_fds > 0) {
  86                 return ENOSYS;
  87         }
  88
  89         message_hdr_put(hdr, msg_type, src, pid);
  90         iov2[0] = (struct iovec){ .iov_base = hdr, .iov_len = sizeof(hdr) };
  91         memcpy(&iov2[1], iov, iovlen * sizeof(*iov));
  92
  93         status = ctdbd_messaging_send_iov(ctx->conn, pid.vnn, pid.pid,
  94                                           iov2, iovlen+1);
  95         if (NT_STATUS_IS_OK(status)) {
  96                 return 0;
  97         }
  98         return map_errno_from_nt_status(status);
  99 }
 100
 101 static int messaging_ctdbd_destructor(struct messaging_ctdbd_context *ctx)
 102 {
 103         /*
 104          * The global connection just went away
 105          */
 106         global_ctdb_connection_pid = 0;
 107         global_ctdbd_connection = NULL;
 108         return 0;
 109 }
 110
 111 static void messaging_ctdb_recv(
 112         uint32_t src_vnn, uint32_t dst_vnn, uint64_t dst_srvid,
 113         const uint8_t *msg, size_t msg_len, void *private_data)
 114 {
 115         struct messaging_context *msg_ctx = talloc_get_type_abort(
 116                 private_data, struct messaging_context);
 117         struct server_id me = messaging_server_id(msg_ctx);
 118         NTSTATUS status;
 119         struct iovec iov;
 120         struct server_id src, dst;
 121         enum messaging_type msg_type;
 122         struct server_id_buf idbuf;
 123
 124         if (msg_len < MESSAGE_HDR_LENGTH) {
 125                 DEBUG(1, ("%s: message too short: %u\n", __func__,
 126                           (unsigned)msg_len));
 127                 return;
 128         }
 129
 130         message_hdr_get(&msg_type, &src, &dst, msg);
 131
 132         iov = (struct iovec) {
 133                 .iov_base = discard_const_p(uint8_t, msg) + MESSAGE_HDR_LENGTH,
 134                 .iov_len = msg_len - MESSAGE_HDR_LENGTH
 135         };
 136
 137         DEBUG(10, ("%s: Received message 0x%x len %u from %s\n",
 138                    __func__, (unsigned)msg_type, (unsigned)msg_len,
 139                    server_id_str_buf(src, &idbuf)));
 140
 141         if (!server_id_same_process(&me, &dst)) {
 142                 struct server_id_buf id1, id2;
 143
 144                 DEBUG(10, ("%s: I'm %s, ignoring msg to %s\n", __func__,
 145                            server_id_str_buf(me, &id1),
 146                            server_id_str_buf(dst, &id2)));
 147                 return;
 148         }
 149
 150         /*
 151          * Go through the event loop
 152          */
 153
 154         status = messaging_send_iov_from(msg_ctx, src, dst, msg_type,
 155                                          &iov, 1, NULL, 0);
 156
 157         if (!NT_STATUS_IS_OK(status)) {
 158                 DEBUG(10, ("%s: messaging_send_iov_from failed: %s\n",
 159                            __func__, nt_errstr(status)));
 160         }
 161 }
 162
 163 NTSTATUS messaging_ctdbd_init(struct messaging_context *msg_ctx,
 164                               TALLOC_CTX *mem_ctx,
 165                               struct messaging_backend **presult)
 166 {
 167         struct messaging_backend *result;
 168         struct messaging_ctdbd_context *ctx;
 169         NTSTATUS status;
 170
 171         if (!(result = talloc(mem_ctx, struct messaging_backend))) {
 172                 DEBUG(0, ("talloc failed\n"));
 173                 return NT_STATUS_NO_MEMORY;
 174         }
 175
 176         if (!(ctx = talloc(result, struct messaging_ctdbd_context))) {
 177                 DEBUG(0, ("talloc failed\n"));
 178                 TALLOC_FREE(result);
 179                 return NT_STATUS_NO_MEMORY;
 180         }
 181
 182         status = ctdbd_messaging_connection(ctx, &ctx->conn);
 183
 184         if (!NT_STATUS_IS_OK(status)) {
 185                 DEBUG(10, ("ctdbd_messaging_connection failed: %s\n",
 186                            nt_errstr(status)));
 187                 TALLOC_FREE(result);
 188                 return status;
 189         }
 190
 191         status = ctdbd_register_msg_ctx(ctx->conn, msg_ctx);
 192
 193         if (!NT_STATUS_IS_OK(status)) {
 194                 DEBUG(10, ("ctdbd_register_msg_ctx failed: %s\n",
 195                            nt_errstr(status)));
 196                 TALLOC_FREE(result);
 197                 return status;
 198         }
 199
 200         status = register_with_ctdbd(ctx->conn, getpid(),
 201                                      messaging_ctdb_recv, msg_ctx);
 202
 203         global_ctdb_connection_pid = getpid();
 204         global_ctdbd_connection = ctx->conn;
 205         talloc_set_destructor(ctx, messaging_ctdbd_destructor);
 206
 207         set_my_vnn(ctdbd_vnn(ctx->conn));
 208
 209         result->send_fn = messaging_ctdb_send;
 210         result->private_data = (void *)ctx;
 211
 212         *presult = result;
 213         return NT_STATUS_OK;
 214 }