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 3 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, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 #include "includes.h"
  25 #include "lib/socket/socket.h"
  26 #include "lib/events/events.h"
  27 #include "libcli/composite/composite.h"
  28 #include "libcli/resolve/resolve.h"
  29 #include "param/param.h"
  30
  31
  32 struct connect_state {
  33         struct socket_context *sock;
  34         const struct socket_address *my_address;
  35         const struct socket_address *server_address;
  36         uint32_t flags;
  37 };
  38
  39 static void socket_connect_handler(struct event_context *ev,
  40                                    struct fd_event *fde,
  41                                    uint16_t flags, void *private);
  42 static void continue_resolve_name(struct composite_context *ctx);
  43 static void continue_socket_connect(struct composite_context *creq);
  44
  45 /*
  46   call the real socket_connect() call, and setup event handler
  47 */
  48 static void socket_send_connect(struct composite_context *result)
  49 {
  50         struct composite_context *creq;
  51         struct fd_event *fde;
  52         struct connect_state *state = talloc_get_type(result->private_data,
  53                                                       struct connect_state);
  54
  55         creq = talloc_zero(state, struct composite_context);
  56         if (composite_nomem(creq, result)) return;
  57         creq->state = COMPOSITE_STATE_IN_PROGRESS;
  58         creq->event_ctx = result->event_ctx;
  59         creq->async.fn = continue_socket_connect;
  60         creq->async.private_data = result;
  61
  62         result->status = socket_connect(state->sock,
  63                                         state->my_address,
  64                                         state->server_address,
  65                                         state->flags);
  66         if (NT_STATUS_IS_ERR(result->status) &&
  67             !NT_STATUS_EQUAL(result->status,
  68                              NT_STATUS_MORE_PROCESSING_REQUIRED)) {
  69                 composite_error(result, result->status);
  70                 return;
  71         }
  72
  73         fde = event_add_fd(result->event_ctx, result,
  74                            socket_get_fd(state->sock),
  75                            EVENT_FD_READ|EVENT_FD_WRITE,
  76                            socket_connect_handler, result);
  77         composite_nomem(fde, result);
  78 }
  79
  80
  81 /*
  82   send a socket connect, potentially doing some name resolution first
  83 */
  84 struct composite_context *socket_connect_send(struct socket_context *sock,
  85                                               struct socket_address *my_address,
  86                                               struct socket_address *server_address,
  87                                               uint32_t flags,
  88                                               const char **name_resolve_order,
  89                                               struct event_context *event_ctx)
  90 {
  91         struct composite_context *result;
  92         struct connect_state *state;
  93
  94         result = talloc_zero(sock, struct composite_context);
  95         if (result == NULL) return NULL;
  96         result->state = COMPOSITE_STATE_IN_PROGRESS;
  97         result->event_ctx = event_ctx;
  98
  99         state = talloc_zero(result, struct connect_state);
 100         if (composite_nomem(state, result)) return result;
 101         result->private_data = state;
 102
 103         state->sock = talloc_reference(state, sock);
 104         if (composite_nomem(state->sock, result)) return result;
 105
 106         if (my_address) {
 107                 void *ref = talloc_reference(state, my_address);
 108                 if (composite_nomem(ref, result)) {
 109                         return result;
 110                 }
 111                 state->my_address = my_address;
 112         }
 113
 114         {
 115                 void *ref = talloc_reference(state, server_address);
 116                 if (composite_nomem(ref, result)) {
 117                         return result;
 118                 }
 119                 state->server_address = server_address;
 120         }
 121
 122         state->flags = flags;
 123
 124         set_blocking(socket_get_fd(sock), false);
 125
 126         if (server_address->addr && strcmp(sock->backend_name, "ipv4") == 0) {
 127                 struct nbt_name name;
 128                 struct composite_context *creq;
 129                 make_nbt_name_client(&name, server_address->addr);
 130                 creq = resolve_name_send(&name, result->event_ctx,
 131                                          lp_name_resolve_order(global_loadparm));
 132                 if (composite_nomem(creq, result)) return result;
 133                 composite_continue(result, creq, continue_resolve_name, result);
 134                 return result;
 135         }
 136
 137         socket_send_connect(result);
 138
 139         return result;
 140 }
 141
 142 /*
 143   handle write events on connect completion
 144 */
 145 static void socket_connect_handler(struct event_context *ev,
 146                                    struct fd_event *fde,
 147                                    uint16_t flags, void *private)
 148 {
 149         struct composite_context *result =
 150                 talloc_get_type(private, struct composite_context);
 151         struct connect_state *state = talloc_get_type(result->private_data,
 152                                                       struct connect_state);
 153
 154         result->status = socket_connect_complete(state->sock, state->flags);
 155         if (!composite_is_ok(result)) return;
 156
 157         composite_done(result);
 158 }
 159
 160 /*
 161   recv name resolution reply then send the connect
 162 */
 163 static void continue_resolve_name(struct composite_context *creq)
 164 {
 165         struct composite_context *result = talloc_get_type(creq->async.private_data,
 166                                                            struct composite_context);
 167         struct connect_state *state = talloc_get_type(result->private_data, struct connect_state);
 168         const char *addr;
 169
 170         result->status = resolve_name_recv(creq, state, &addr);
 171         if (!composite_is_ok(result)) return;
 172
 173         state->server_address = socket_address_from_strings(state, state->sock->backend_name,
 174                                                             addr, state->server_address->port);
 175         if (composite_nomem(state->server_address, result)) return;
 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                            struct socket_address *my_address,
 209                            struct socket_address *server_address,
 210                            uint32_t flags, const char **name_resolve_order,
 211                            struct event_context *ev)
 212 {
 213         struct composite_context *ctx;
 214         ctx = socket_connect_send(sock, my_address,
 215                                   server_address, flags, name_resolve_order, ev);
 216         return socket_connect_recv(ctx);
 217 }