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 #include "lib/cluster_support.h"
  27
  28
  29 struct messaging_ctdbd_context {
  30         struct ctdbd_connection *conn;
  31 };
  32
  33 /*
  34  * This is a Samba3 hack/optimization. Routines like process_exists need to
  35  * talk to ctdbd, and they don't get handed a messaging context.
  36  */
  37 static struct ctdbd_connection *global_ctdbd_connection;
  38 static int global_ctdb_connection_pid;
  39
  40 struct ctdbd_connection *messaging_ctdbd_connection(void)
  41 {
  42         if (!lp_clustering()) {
  43                 return NULL;
  44         }
  45
  46         if (global_ctdb_connection_pid == 0 &&
  47             global_ctdbd_connection == NULL) {
  48                 struct tevent_context *ev;
  49                 struct messaging_context *msg;
  50
  51                 ev = samba_tevent_context_init(NULL);
  52                 if (!ev) {
  53                         DEBUG(0,("samba_tevent_context_init failed\n"));
  54                         return NULL;
  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         uint8_t hdr[MESSAGE_HDR_LENGTH];
  84         struct iovec iov2[iovlen+1];
  85         NTSTATUS status;
  86
  87         if (num_fds > 0) {
  88                 return ENOSYS;
  89         }
  90
  91         message_hdr_put(hdr, msg_type, src, pid);
  92         iov2[0] = (struct iovec){ .iov_base = hdr, .iov_len = sizeof(hdr) };
  93         memcpy(&iov2[1], iov, iovlen * sizeof(*iov));
  94
  95         status = ctdbd_messaging_send_iov(ctx->conn, pid.vnn, pid.pid,
  96                                           iov2, iovlen+1);
  97         if (NT_STATUS_IS_OK(status)) {
  98                 return 0;
  99         }
 100         return map_errno_from_nt_status(status);
 101 }
 102
 103 static int messaging_ctdbd_destructor(struct messaging_ctdbd_context *ctx)
 104 {
 105         /*
 106          * The global connection just went away
 107          */
 108         global_ctdb_connection_pid = 0;
 109         global_ctdbd_connection = NULL;
 110         return 0;
 111 }
 112
 113 static int messaging_ctdb_recv(
 114         uint32_t src_vnn, uint32_t dst_vnn, uint64_t dst_srvid,
 115         const uint8_t *msg, size_t msg_len, void *private_data)
 116 {
 117         struct messaging_context *msg_ctx = talloc_get_type_abort(
 118                 private_data, struct messaging_context);
 119         struct server_id me = messaging_server_id(msg_ctx);
 120         NTSTATUS status;
 121         struct iovec iov;
 122         struct server_id src, dst;
 123         enum messaging_type msg_type;
 124         struct server_id_buf idbuf;
 125
 126         if (msg_len < MESSAGE_HDR_LENGTH) {
 127                 DEBUG(1, ("%s: message too short: %u\n", __func__,
 128                           (unsigned)msg_len));
 129                 return 0;
 130         }
 131
 132         message_hdr_get(&msg_type, &src, &dst, msg);
 133
 134         iov = (struct iovec) {
 135                 .iov_base = discard_const_p(uint8_t, msg) + MESSAGE_HDR_LENGTH,
 136                 .iov_len = msg_len - MESSAGE_HDR_LENGTH
 137         };
 138
 139         DEBUG(10, ("%s: Received message 0x%x len %u from %s\n",
 140                    __func__, (unsigned)msg_type, (unsigned)msg_len,
 141                    server_id_str_buf(src, &idbuf)));
 142
 143         if (!server_id_same_process(&me, &dst)) {
 144                 struct server_id_buf id1, id2;
 145
 146                 DEBUG(10, ("%s: I'm %s, ignoring msg to %s\n", __func__,
 147                            server_id_str_buf(me, &id1),
 148                            server_id_str_buf(dst, &id2)));
 149                 return 0;
 150         }
 151
 152         /*
 153          * Go through the event loop
 154          */
 155
 156         status = messaging_send_iov_from(msg_ctx, src, dst, msg_type,
 157                                          &iov, 1, NULL, 0);
 158
 159         if (!NT_STATUS_IS_OK(status)) {
 160                 DEBUG(10, ("%s: messaging_send_iov_from failed: %s\n",
 161                            __func__, nt_errstr(status)));
 162         }
 163
 164         return 0;
 165 }
 166
 167 NTSTATUS messaging_ctdbd_init(struct messaging_context *msg_ctx,
 168                               TALLOC_CTX *mem_ctx,
 169                               struct messaging_backend **presult)
 170 {
 171         struct messaging_backend *result;
 172         struct messaging_ctdbd_context *ctx;
 173         NTSTATUS status;
 174         int ret;
 175
 176         if (!(result = talloc(mem_ctx, struct messaging_backend))) {
 177                 DEBUG(0, ("talloc failed\n"));
 178                 return NT_STATUS_NO_MEMORY;
 179         }
 180
 181         if (!(ctx = talloc(result, struct messaging_ctdbd_context))) {
 182                 DEBUG(0, ("talloc failed\n"));
 183                 TALLOC_FREE(result);
 184                 return NT_STATUS_NO_MEMORY;
 185         }
 186
 187         status = ctdbd_messaging_connection(ctx, lp_ctdbd_socket(),
 188                                             lp_ctdb_timeout(), &ctx->conn);
 189
 190         if (!NT_STATUS_IS_OK(status)) {
 191                 DEBUG(10, ("ctdbd_messaging_connection failed: %s\n",
 192                            nt_errstr(status)));
 193                 TALLOC_FREE(result);
 194                 return status;
 195         }
 196
 197         ret = ctdbd_register_msg_ctx(ctx->conn, msg_ctx);
 198
 199         if (ret != 0) {
 200                 DEBUG(10, ("ctdbd_register_msg_ctx failed: %s\n",
 201                            strerror(ret)));
 202                 TALLOC_FREE(result);
 203                 return map_nt_error_from_unix(ret);
 204         }
 205
 206         ret = register_with_ctdbd(ctx->conn, getpid(),
 207                                   messaging_ctdb_recv, msg_ctx);
 208         if (ret != 0) {
 209                 DEBUG(10, ("register_with_ctdbd failed: %s\n",
 210                            strerror(ret)));
 211                 TALLOC_FREE(result);
 212                 return map_nt_error_from_unix(ret);
 213         }
 214
 215         global_ctdb_connection_pid = getpid();
 216         global_ctdbd_connection = ctx->conn;
 217         talloc_set_destructor(ctx, messaging_ctdbd_destructor);
 218
 219         set_my_vnn(ctdbd_vnn(ctx->conn));
 220
 221         result->send_fn = messaging_ctdb_send;
 222         result->private_data = (void *)ctx;
 223
 224         *presult = result;
 225         return NT_STATUS_OK;
 226 }