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