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;
43 status = socket_pending(dgmsock->sock, &dsize);
44 if (!NT_STATUS_IS_OK(status)) {
49 blob = data_blob_talloc(tmp_ctx, NULL, dsize);
50 if (blob.data == NULL) {
55 status = socket_recvfrom(dgmsock->sock, blob.data, blob.length, &nread,
57 if (!NT_STATUS_IS_OK(status)) {
63 DEBUG(2,("Received dgram packet of length %d from %s:%d\n",
64 (int)blob.length, src->addr, src->port));
66 packet = talloc(tmp_ctx, struct nbt_dgram_packet);
72 /* parse the request */
73 status = ndr_pull_struct_blob(&blob, packet, packet,
74 (ndr_pull_flags_fn_t)ndr_pull_nbt_dgram_packet);
75 if (!NT_STATUS_IS_OK(status)) {
76 DEBUG(2,("Failed to parse incoming NBT DGRAM packet - %s\n",
82 /* if this is a mailslot message, then see if we can dispatch it to a handler */
83 mailslot_name = dgram_mailslot_name(packet);
85 struct dgram_mailslot_handler *dgmslot;
86 dgmslot = dgram_mailslot_find(dgmsock, mailslot_name);
88 dgmslot->handler(dgmslot, packet, src);
90 DEBUG(2,("No mailslot handler for '%s'\n", mailslot_name));
93 /* dispatch if there is a general handler */
94 if (dgmsock->incoming.handler) {
95 dgmsock->incoming.handler(dgmsock, packet, src);
104 handle send events on a nbt dgram socket
106 static void dgm_socket_send(struct nbt_dgram_socket *dgmsock)
108 struct nbt_dgram_request *req;
111 while ((req = dgmsock->send_queue)) {
114 len = req->encoded.length;
115 status = socket_sendto(dgmsock->sock, &req->encoded, &len,
117 if (NT_STATUS_IS_ERR(status)) {
118 DEBUG(3,("Failed to send datagram of length %u to %s:%d: %s\n",
119 (unsigned)req->encoded.length, req->dest->addr, req->dest->port,
121 DLIST_REMOVE(dgmsock->send_queue, req);
126 if (!NT_STATUS_IS_OK(status)) return;
128 DLIST_REMOVE(dgmsock->send_queue, req);
132 EVENT_FD_NOT_WRITEABLE(dgmsock->fde);
138 handle fd events on a nbt_dgram_socket
140 static void dgm_socket_handler(struct event_context *ev, struct fd_event *fde,
141 uint16_t flags, void *private)
143 struct nbt_dgram_socket *dgmsock = talloc_get_type(private,
144 struct nbt_dgram_socket);
145 if (flags & EVENT_FD_WRITE) {
146 dgm_socket_send(dgmsock);
148 if (flags & EVENT_FD_READ) {
149 dgm_socket_recv(dgmsock);
154 initialise a nbt_dgram_socket. The event_ctx is optional, if provided
155 then operations will use that event context
157 struct nbt_dgram_socket *nbt_dgram_socket_init(TALLOC_CTX *mem_ctx,
158 struct event_context *event_ctx)
160 struct nbt_dgram_socket *dgmsock;
163 dgmsock = talloc(mem_ctx, struct nbt_dgram_socket);
164 if (dgmsock == NULL) goto failed;
166 if (event_ctx == NULL) {
167 dgmsock->event_ctx = event_context_init(dgmsock);
169 dgmsock->event_ctx = talloc_reference(dgmsock, event_ctx);
171 if (dgmsock->event_ctx == NULL) goto failed;
173 status = socket_create("ip", SOCKET_TYPE_DGRAM, &dgmsock->sock, 0);
174 if (!NT_STATUS_IS_OK(status)) goto failed;
176 socket_set_option(dgmsock->sock, "SO_BROADCAST", "1");
178 talloc_steal(dgmsock, dgmsock->sock);
180 dgmsock->fde = event_add_fd(dgmsock->event_ctx, dgmsock,
181 socket_get_fd(dgmsock->sock), 0,
182 dgm_socket_handler, dgmsock);
184 dgmsock->send_queue = NULL;
185 dgmsock->incoming.handler = NULL;
186 dgmsock->mailslot_handlers = NULL;
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 = private;
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;
222 req = talloc(dgmsock, struct nbt_dgram_request);
223 if (req == NULL) goto failed;
226 if (talloc_reference(req, dest) == NULL) goto failed;
228 status = ndr_push_struct_blob(&req->encoded, req, packet,
229 (ndr_push_flags_fn_t)ndr_push_nbt_dgram_packet);
230 if (!NT_STATUS_IS_OK(status)) goto failed;
232 DLIST_ADD_END(dgmsock->send_queue, req, struct nbt_dgram_request *);
234 EVENT_FD_WRITEABLE(dgmsock->fde);