2 Unix SMB/CIFS implementation.
4 low level socket handling for nbt dgram requests (UDP138)
6 Copyright (C) Andrew Tridgell 2005
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>.
23 #include "lib/events/events.h"
24 #include "../lib/util/dlinklist.h"
25 #include "libcli/dgram/libdgram.h"
26 #include "lib/socket/socket.h"
27 #include "librpc/gen_ndr/ndr_nbt.h"
31 handle recv events on a nbt dgram socket
33 static void dgm_socket_recv(struct nbt_dgram_socket
*dgmsock
)
35 TALLOC_CTX
*tmp_ctx
= talloc_new(dgmsock
);
37 struct socket_address
*src
;
40 struct nbt_dgram_packet
*packet
;
41 const char *mailslot_name
;
42 enum ndr_err_code ndr_err
;
44 status
= socket_pending(dgmsock
->sock
, &dsize
);
45 if (!NT_STATUS_IS_OK(status
)) {
50 blob
= data_blob_talloc(tmp_ctx
, NULL
, dsize
);
51 if (blob
.data
== NULL
) {
56 status
= socket_recvfrom(dgmsock
->sock
, blob
.data
, blob
.length
, &nread
,
58 if (!NT_STATUS_IS_OK(status
)) {
64 DEBUG(2,("Received dgram packet of length %d from %s:%d\n",
65 (int)blob
.length
, src
->addr
, src
->port
));
67 packet
= talloc(tmp_ctx
, struct nbt_dgram_packet
);
73 /* parse the request */
74 ndr_err
= ndr_pull_struct_blob(&blob
, packet
, dgmsock
->iconv_convenience
, packet
,
75 (ndr_pull_flags_fn_t
)ndr_pull_nbt_dgram_packet
);
76 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err
)) {
77 status
= ndr_map_error2ntstatus(ndr_err
);
78 DEBUG(2,("Failed to parse incoming NBT DGRAM packet - %s\n",
84 /* if this is a mailslot message, then see if we can dispatch it to a handler */
85 mailslot_name
= dgram_mailslot_name(packet
);
87 struct dgram_mailslot_handler
*dgmslot
;
88 dgmslot
= dgram_mailslot_find(dgmsock
, mailslot_name
);
90 dgmslot
->handler(dgmslot
, packet
, src
);
92 DEBUG(2,("No mailslot handler for '%s'\n", mailslot_name
));
95 /* dispatch if there is a general handler */
96 if (dgmsock
->incoming
.handler
) {
97 dgmsock
->incoming
.handler(dgmsock
, packet
, src
);
101 talloc_free(tmp_ctx
);
106 handle send events on a nbt dgram socket
108 static void dgm_socket_send(struct nbt_dgram_socket
*dgmsock
)
110 struct nbt_dgram_request
*req
;
113 while ((req
= dgmsock
->send_queue
)) {
116 len
= req
->encoded
.length
;
117 status
= socket_sendto(dgmsock
->sock
, &req
->encoded
, &len
,
119 if (NT_STATUS_IS_ERR(status
)) {
120 DEBUG(3,("Failed to send datagram of length %u to %s:%d: %s\n",
121 (unsigned)req
->encoded
.length
, req
->dest
->addr
, req
->dest
->port
,
123 DLIST_REMOVE(dgmsock
->send_queue
, req
);
128 if (!NT_STATUS_IS_OK(status
)) return;
130 DLIST_REMOVE(dgmsock
->send_queue
, req
);
134 EVENT_FD_NOT_WRITEABLE(dgmsock
->fde
);
140 handle fd events on a nbt_dgram_socket
142 static void dgm_socket_handler(struct tevent_context
*ev
, struct tevent_fd
*fde
,
143 uint16_t flags
, void *private_data
)
145 struct nbt_dgram_socket
*dgmsock
= talloc_get_type(private_data
,
146 struct nbt_dgram_socket
);
147 if (flags
& EVENT_FD_WRITE
) {
148 dgm_socket_send(dgmsock
);
150 if (flags
& EVENT_FD_READ
) {
151 dgm_socket_recv(dgmsock
);
156 initialise a nbt_dgram_socket. The event_ctx is optional, if provided
157 then operations will use that event context
159 struct nbt_dgram_socket
*nbt_dgram_socket_init(TALLOC_CTX
*mem_ctx
,
160 struct tevent_context
*event_ctx
,
161 struct smb_iconv_convenience
*iconv_convenience
)
163 struct nbt_dgram_socket
*dgmsock
;
166 dgmsock
= talloc(mem_ctx
, struct nbt_dgram_socket
);
167 if (dgmsock
== NULL
) goto failed
;
169 dgmsock
->event_ctx
= event_ctx
;
170 if (dgmsock
->event_ctx
== NULL
) goto failed
;
172 status
= socket_create("ip", SOCKET_TYPE_DGRAM
, &dgmsock
->sock
, 0);
173 if (!NT_STATUS_IS_OK(status
)) goto failed
;
175 socket_set_option(dgmsock
->sock
, "SO_BROADCAST", "1");
177 talloc_steal(dgmsock
, dgmsock
->sock
);
179 dgmsock
->fde
= event_add_fd(dgmsock
->event_ctx
, dgmsock
,
180 socket_get_fd(dgmsock
->sock
), 0,
181 dgm_socket_handler
, dgmsock
);
183 dgmsock
->send_queue
= NULL
;
184 dgmsock
->incoming
.handler
= NULL
;
185 dgmsock
->mailslot_handlers
= NULL
;
186 dgmsock
->iconv_convenience
= iconv_convenience
;
191 talloc_free(dgmsock
);
197 setup a handler for generic incoming requests
199 NTSTATUS
dgram_set_incoming_handler(struct nbt_dgram_socket
*dgmsock
,
200 void (*handler
)(struct nbt_dgram_socket
*,
201 struct nbt_dgram_packet
*,
202 struct socket_address
*),
205 dgmsock
->incoming
.handler
= handler
;
206 dgmsock
->incoming
.private_data
= private_data
;
207 EVENT_FD_READABLE(dgmsock
->fde
);
213 queue a datagram for send
215 NTSTATUS
nbt_dgram_send(struct nbt_dgram_socket
*dgmsock
,
216 struct nbt_dgram_packet
*packet
,
217 struct socket_address
*dest
)
219 struct nbt_dgram_request
*req
;
220 NTSTATUS status
= NT_STATUS_NO_MEMORY
;
221 enum ndr_err_code ndr_err
;
223 req
= talloc(dgmsock
, struct nbt_dgram_request
);
224 if (req
== NULL
) goto failed
;
227 if (talloc_reference(req
, dest
) == NULL
) goto failed
;
229 ndr_err
= ndr_push_struct_blob(&req
->encoded
, req
, dgmsock
->iconv_convenience
, packet
,
230 (ndr_push_flags_fn_t
)ndr_push_nbt_dgram_packet
);
231 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err
)) {
232 status
= ndr_map_error2ntstatus(ndr_err
);
236 DLIST_ADD_END(dgmsock
->send_queue
, req
, struct nbt_dgram_request
*);
238 EVENT_FD_WRITEABLE(dgmsock
->fde
);