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 "libcli/composite/composite.h"
  29
  30
  31 struct connect_state {
  32         struct socket_context *sock;
  33         const char *my_address;
  34         int my_port;
  35         const char *server_address;
  36         int server_port;
  37         uint32_t flags;
  38 };
  39
  40 static void socket_connect_handler(struct event_context *ev,
  41                                    struct fd_event *fde,
  42                                    uint16_t flags, void *private);
  43 static void continue_resolve_name(struct composite_context *ctx);
  44 static void continue_socket_connect(struct composite_context *creq);
  45
  46 /*
  47   call the real socket_connect() call, and setup event handler
  48 */
  49 static void socket_send_connect(struct composite_context *result)
  50 {
  51         struct composite_context *creq;
  52         struct fd_event *fde;
  53         struct connect_state *state = talloc_get_type(result->private_data,
  54                                                       struct connect_state);
  55
  56         creq = talloc_zero(state, struct composite_context);
  57         if (composite_nomem(creq, result)) return;
  58         creq->state = COMPOSITE_STATE_IN_PROGRESS;
  59         creq->event_ctx = result->event_ctx;
  60         creq->async.fn = continue_socket_connect;
  61         creq->async.private_data = result;
  62
  63         result->status = socket_connect(state->sock,
  64                                         state->my_address,
  65                                         state->my_port,
  66                                         state->server_address,
  67                                         state->server_port,
  68                                         state->flags);
  69         if (NT_STATUS_IS_ERR(result->status) &&
  70             !NT_STATUS_EQUAL(result->status,
  71                              NT_STATUS_MORE_PROCESSING_REQUIRED)) {
  72                 composite_error(result, result->status);
  73                 return;
  74         }
  75
  76         fde = event_add_fd(result->event_ctx, result,
  77                            socket_get_fd(state->sock),
  78                            EVENT_FD_READ|EVENT_FD_WRITE,
  79                            socket_connect_handler, result);
  80         composite_nomem(fde, result);
  81 }
  82
  83
  84 /*
  85   send a socket connect, potentially doing some name resolution first
  86 */
  87 struct composite_context *socket_connect_send(struct socket_context *sock,
  88                                               const char *my_address,
  89                                               int my_port,
  90                                               const char *server_address,
  91                                               int server_port,
  92                                               uint32_t flags,
  93                                               struct event_context *event_ctx)
  94 {
  95         struct composite_context *result;
  96         struct connect_state *state;
  97
  98         result = talloc_zero(sock, struct composite_context);
  99         if (result == NULL) return NULL;
 100         result->state = COMPOSITE_STATE_IN_PROGRESS;
 101         result->event_ctx = event_ctx;
 102
 103         state = talloc_zero(result, struct connect_state);
 104         if (composite_nomem(state, result)) goto failed;
 105         result->private_data = state;
 106
 107         state->sock = talloc_reference(state, sock);
 108         if (composite_nomem(state->sock, result)) goto failed;
 109
 110         if (my_address) {
 111                 state->my_address = talloc_strdup(state, my_address);
 112                 if (composite_nomem(state->my_address, result)) goto failed;
 113         }
 114         state->my_port = my_port;
 115
 116         state->server_address = talloc_strdup(state, server_address);
 117         if (composite_nomem(state->server_address, result)) goto failed;
 118
 119         state->server_port = server_port;
 120         state->flags = flags;
 121
 122         set_blocking(socket_get_fd(sock), False);
 123
 124         if (strcmp(sock->backend_name, "ipv4") == 0) {
 125                 struct nbt_name name;
 126                 struct composite_context *creq;
 127                 make_nbt_name_client(&name, server_address);
 128                 creq = resolve_name_send(&name, result->event_ctx,
 129                                          lp_name_resolve_order());
 130                 if (composite_nomem(creq, result)) goto failed;
 131                 composite_continue(result, creq, continue_resolve_name, result);
 132                 return result;
 133         }
 134
 135         socket_send_connect(result);
 136
 137         return result;
 138
 139 failed:
 140         composite_error(result, result->status);
 141         return result;
 142 }
 143
 144 /*
 145   handle write events on connect completion
 146 */
 147 static void socket_connect_handler(struct event_context *ev,
 148                                    struct fd_event *fde,
 149                                    uint16_t flags, void *private)
 150 {
 151         struct composite_context *result =
 152                 talloc_get_type(private, struct composite_context);
 153         struct connect_state *state = talloc_get_type(result->private_data,
 154                                                       struct connect_state);
 155
 156         result->status = socket_connect_complete(state->sock, state->flags);
 157         if (!composite_is_ok(result)) return;
 158
 159         composite_done(result);
 160 }
 161
 162 /*
 163   recv name resolution reply then send the connect
 164 */
 165 static void continue_resolve_name(struct composite_context *creq)
 166 {
 167         struct composite_context *result = talloc_get_type(creq->async.private_data,
 168                                                            struct composite_context);
 169         struct connect_state *state = talloc_get_type(result->private_data, struct connect_state);
 170         const char *addr;
 171
 172         result->status = resolve_name_recv(creq, state, &addr);
 173         if (!composite_is_ok(result)) return;
 174
 175         state->server_address = addr;
 176
 177         socket_send_connect(result);
 178 }
 179
 180 /*
 181   called when a connect has finished. Complete the top level composite context
 182 */
 183 static void continue_socket_connect(struct composite_context *creq)
 184 {
 185         struct composite_context *result = talloc_get_type(creq->async.private_data,
 186                                                            struct composite_context);
 187         result->status = creq->status;
 188         if (!composite_is_ok(result)) return;
 189         composite_done(result);
 190 }
 191
 192
 193 /*
 194   wait for a socket_connect_send() to finish
 195 */
 196 NTSTATUS socket_connect_recv(struct composite_context *result)
 197 {
 198         NTSTATUS status = composite_wait(result);
 199         talloc_free(result);
 200         return status;
 201 }
 202
 203
 204 /*
 205   like socket_connect() but takes an event context, doing a semi-async connect
 206 */
 207 NTSTATUS socket_connect_ev(struct socket_context *sock,
 208                            const char *my_address, int my_port,
 209                            const char *server_address, int server_port,
 210                            uint32_t flags, struct event_context *ev)
 211 {
 212         struct composite_context *ctx;
 213         ctx = socket_connect_send(sock, my_address, my_port,
 214                                   server_address, server_port, flags, ev);
 215         return socket_connect_recv(ctx);
 216 }