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