source4/lib/socket/connect.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    implements a non-blocking connect operation that is aware of the samba4
   5    events system
   6
   7    Copyright (C) Andrew Tridgell 2005
   8    Copyright (C) Volker Lendecke 2005
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 2 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program; if not, write to the Free Software
  22    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23 */
  24
  25 #include "includes.h"
  26 #include "lib/socket/socket.h"
  27 #include "lib/events/events.h"
  28 #include "librpc/gen_ndr/nbt.h"
  29 #include "libcli/composite/composite.h"
  30
  31
  32 struct connect_state {
  33         struct socket_context *sock;
  34         const char *my_address;
  35         int my_port;
  36         const char *server_address;
  37         int server_port;
  38         uint32_t flags;
  39 };
  40
  41 static void socket_connect_handler(struct event_context *ev,
  42                                    struct fd_event *fde,
  43                                    uint16_t flags, void *private);
  44 static void continue_resolve_name(struct composite_context *ctx);
  45 static void continue_socket_connect(struct composite_context *creq);
  46
  47 /*
  48   call the real socket_connect() call, and setup event handler
  49 */
  50 static void socket_send_connect(struct composite_context *result)
  51 {
  52         struct composite_context *creq;
  53         struct fd_event *fde;
  54         struct connect_state *state = talloc_get_type(result->private_data,
  55                                                       struct connect_state);
  56
  57         creq = talloc_zero(state, struct composite_context);
  58         if (composite_nomem(creq, result)) return;
  59         creq->state = COMPOSITE_STATE_IN_PROGRESS;
  60         creq->event_ctx = result->event_ctx;
  61         creq->async.fn = continue_socket_connect;
  62         creq->async.private_data = result;
  63
  64         result->status = socket_connect(state->sock,
  65                                         state->my_address,
  66                                         state->my_port,
  67                                         state->server_address,
  68                                         state->server_port,
  69                                         state->flags);
  70         if (NT_STATUS_IS_ERR(result->status) &&
  71             !NT_STATUS_EQUAL(result->status,
  72                              NT_STATUS_MORE_PROCESSING_REQUIRED)) {
  73                 composite_error(result, result->status);
  74                 return;
  75         }
  76
  77         fde = event_add_fd(result->event_ctx, result,
  78                            socket_get_fd(state->sock),
  79                            EVENT_FD_WRITE,
  80                            socket_connect_handler, result);
  81         composite_nomem(fde, result);
  82 }
  83
  84
  85 /*
  86   send a socket connect, potentially doing some name resolution first
  87 */
  88 struct composite_context *socket_connect_send(struct socket_context *sock,
  89                                               const char *my_address,
  90                                               int my_port,
  91                                               const char *server_address,
  92                                               int server_port,
  93                                               uint32_t flags,
  94                                               struct event_context *event_ctx)
  95 {
  96         struct composite_context *result;
  97         struct connect_state *state;
  98
  99         result = talloc_zero(sock, struct composite_context);
 100         if (result == NULL) return NULL;
 101         result->state = COMPOSITE_STATE_IN_PROGRESS;
 102         result->event_ctx = event_ctx;
 103
 104         state = talloc_zero(result, struct connect_state);
 105         if (composite_nomem(state, result)) goto failed;
 106         result->private_data = state;
 107
 108         state->sock = talloc_reference(state, sock);
 109         if (composite_nomem(state->sock, result)) goto failed;
 110
 111         if (my_address) {
 112                 state->my_address = talloc_strdup(state, my_address);
 113                 if (composite_nomem(state->my_address, result)) goto failed;
 114         }
 115         state->my_port = my_port;
 116
 117         state->server_address = talloc_strdup(state, server_address);
 118         if (composite_nomem(state->server_address, result)) goto failed;
 119
 120         state->server_port = server_port;
 121         state->flags = flags;
 122
 123         set_blocking(socket_get_fd(sock), False);
 124
 125         if (strcmp(sock->backend_name, "ipv4") == 0) {
 126                 struct nbt_name name;
 127                 struct composite_context *creq;
 128                 make_nbt_name_client(&name, server_address);
 129                 creq = resolve_name_send(&name, result->event_ctx,
 130                                          lp_name_resolve_order());
 131                 if (composite_nomem(creq, result)) goto failed;
 132                 composite_continue(result, creq, continue_resolve_name, result);
 133                 return result;
 134         }
 135
 136         socket_send_connect(result);
 137
 138         return result;
 139
 140 failed:
 141         composite_trigger_error(result);
 142         return result;
 143 }
 144
 145 /*
 146   handle write events on connect completion
 147 */
 148 static void socket_connect_handler(struct event_context *ev,
 149                                    struct fd_event *fde,
 150                                    uint16_t flags, void *private)
 151 {
 152         struct composite_context *result =
 153                 talloc_get_type(private, struct composite_context);
 154         struct connect_state *state = talloc_get_type(result->private_data,
 155                                                       struct connect_state);
 156
 157         result->status = socket_connect_complete(state->sock, state->flags);
 158         if (!composite_is_ok(result)) return;
 159
 160         composite_done(result);
 161 }
 162
 163 /*
 164   recv name resolution reply then send the connect
 165 */
 166 static void continue_resolve_name(struct composite_context *creq)
 167 {
 168         struct composite_context *result = talloc_get_type(creq->async.private_data,
 169                                                            struct composite_context);
 170         struct connect_state *state = talloc_get_type(result->private_data, struct connect_state);
 171         const char *addr;
 172
 173         result->status = resolve_name_recv(creq, state, &addr);
 174         if (!composite_is_ok(result)) return;
 175
 176         state->server_address = addr;
 177
 178         socket_send_connect(result);
 179 }
 180
 181 /*
 182   called when a connect has finished. Complete the top level composite context
 183 */
 184 static void continue_socket_connect(struct composite_context *creq)
 185 {
 186         struct composite_context *result = talloc_get_type(creq->async.private_data,
 187                                                            struct composite_context);
 188         result->status = creq->status;
 189         if (!composite_is_ok(result)) return;
 190         composite_done(result);
 191 }
 192
 193
 194 /*
 195   wait for a socket_connect_send() to finish
 196 */
 197 NTSTATUS socket_connect_recv(struct composite_context *result)
 198 {
 199         NTSTATUS status = composite_wait(result);
 200         talloc_free(result);
 201         return status;
 202 }
 203
 204
 205 /*
 206   like socket_connect() but takes an event context, doing a semi-async connect
 207 */
 208 NTSTATUS socket_connect_ev(struct socket_context *sock,
 209                            const char *my_address, int my_port,
 210                            const char *server_address, int server_port,
 211                            uint32_t flags, struct event_context *ev)
 212 {
 213         struct composite_context *ctx;
 214         ctx = socket_connect_send(sock, my_address, my_port,
 215                                   server_address, server_port, flags, ev);
 216         return socket_connect_recv(ctx);
 217 }