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 2 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, write to the Free Software
20 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 #include "lib/events/events.h"
25 #include "dlinklist.h"
26 #include "libcli/nbt/libnbt.h"
27 #include "libcli/dgram/libdgram.h"
28 #include "lib/socket/socket.h"
32 handle recv events on a nbt dgram socket
34 static void dgm_socket_recv(struct nbt_dgram_socket *dgmsock)
36 TALLOC_CTX *tmp_ctx = talloc_new(dgmsock);
38 struct nbt_peer_socket src;
41 struct nbt_dgram_packet *packet;
42 const char *mailslot_name;
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, 0,
57 &src.addr, &src.port);
58 if (!NT_STATUS_IS_OK(status)) {
62 talloc_steal(tmp_ctx, src.addr);
65 DEBUG(2,("Received dgram packet of length %d from %s:%d\n",
66 (int)blob.length, src.addr, src.port));
68 packet = talloc(tmp_ctx, struct nbt_dgram_packet);
74 /* parse the request */
75 status = ndr_pull_struct_blob(&blob, packet, packet,
76 (ndr_pull_flags_fn_t)ndr_pull_nbt_dgram_packet);
77 if (!NT_STATUS_IS_OK(status)) {
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, 0,
118 req->dest.addr, req->dest.port);
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 event_context *ev, struct fd_event *fde,
143 uint16_t flags, void *private)
145 struct nbt_dgram_socket *dgmsock = talloc_get_type(private,
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 event_context *event_ctx)
162 struct nbt_dgram_socket *dgmsock;
165 dgmsock = talloc(mem_ctx, struct nbt_dgram_socket);
166 if (dgmsock == NULL) goto failed;
168 if (event_ctx == NULL) {
169 dgmsock->event_ctx = event_context_init(dgmsock);
171 dgmsock->event_ctx = talloc_reference(dgmsock, event_ctx);
173 if (dgmsock->event_ctx == NULL) goto failed;
175 status = socket_create("ip", SOCKET_TYPE_DGRAM, &dgmsock->sock, 0);
176 if (!NT_STATUS_IS_OK(status)) goto failed;
178 socket_set_option(dgmsock->sock, "SO_BROADCAST", "1");
180 talloc_steal(dgmsock, dgmsock->sock);
182 dgmsock->fde = event_add_fd(dgmsock->event_ctx, dgmsock,
183 socket_get_fd(dgmsock->sock), 0,
184 dgm_socket_handler, dgmsock);
186 dgmsock->send_queue = NULL;
187 dgmsock->incoming.handler = NULL;
188 dgmsock->mailslot_handlers = NULL;
193 talloc_free(dgmsock);
199 setup a handler for generic incoming requests
201 NTSTATUS dgram_set_incoming_handler(struct nbt_dgram_socket *dgmsock,
202 void (*handler)(struct nbt_dgram_socket *,
203 struct nbt_dgram_packet *,
204 const struct nbt_peer_socket *),
207 dgmsock->incoming.handler = handler;
208 dgmsock->incoming.private = private;
209 EVENT_FD_READABLE(dgmsock->fde);
215 queue a datagram for send
217 NTSTATUS nbt_dgram_send(struct nbt_dgram_socket *dgmsock,
218 struct nbt_dgram_packet *packet,
219 const struct nbt_peer_socket *dest)
221 struct nbt_dgram_request *req;
222 NTSTATUS status = NT_STATUS_NO_MEMORY;
224 req = talloc(dgmsock, struct nbt_dgram_request);
225 if (req == NULL) goto failed;
227 req->dest.port = dest->port;
228 req->dest.addr = talloc_strdup(req, dest->addr);
229 if (req->dest.addr == NULL) goto failed;
231 status = ndr_push_struct_blob(&req->encoded, req, packet,
232 (ndr_push_flags_fn_t)ndr_push_nbt_dgram_packet);
233 if (!NT_STATUS_IS_OK(status)) goto failed;
235 DLIST_ADD_END(dgmsock->send_queue, req, struct nbt_dgram_request *);
237 EVENT_FD_WRITEABLE(dgmsock->fde);