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 "param/param.h"
28 #include "librpc/gen_ndr/ndr_nbt.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 socket_address *src;
41 struct nbt_dgram_packet *packet;
42 const char *mailslot_name;
43 enum ndr_err_code ndr_err;
45 status = socket_pending(dgmsock->sock, &dsize);
46 if (!NT_STATUS_IS_OK(status)) {
51 blob = data_blob_talloc(tmp_ctx, NULL, dsize);
52 if (blob.data == NULL) {
57 status = socket_recvfrom(dgmsock->sock, blob.data, blob.length, &nread,
59 if (!NT_STATUS_IS_OK(status)) {
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 ndr_err = ndr_pull_struct_blob(&blob, packet, dgmsock->iconv_convenience, packet,
76 (ndr_pull_flags_fn_t)ndr_pull_nbt_dgram_packet);
77 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
78 status = ndr_map_error2ntstatus(ndr_err);
79 DEBUG(2,("Failed to parse incoming NBT DGRAM packet - %s\n",
85 /* if this is a mailslot message, then see if we can dispatch it to a handler */
86 mailslot_name = dgram_mailslot_name(packet);
88 struct dgram_mailslot_handler *dgmslot;
89 dgmslot = dgram_mailslot_find(dgmsock, mailslot_name);
91 dgmslot->handler(dgmslot, packet, src);
93 DEBUG(2,("No mailslot handler for '%s'\n", mailslot_name));
96 /* dispatch if there is a general handler */
97 if (dgmsock->incoming.handler) {
98 dgmsock->incoming.handler(dgmsock, packet, src);
102 talloc_free(tmp_ctx);
107 handle send events on a nbt dgram socket
109 static void dgm_socket_send(struct nbt_dgram_socket *dgmsock)
111 struct nbt_dgram_request *req;
114 while ((req = dgmsock->send_queue)) {
117 len = req->encoded.length;
118 status = socket_sendto(dgmsock->sock, &req->encoded, &len,
120 if (NT_STATUS_IS_ERR(status)) {
121 DEBUG(3,("Failed to send datagram of length %u to %s:%d: %s\n",
122 (unsigned)req->encoded.length, req->dest->addr, req->dest->port,
124 DLIST_REMOVE(dgmsock->send_queue, req);
129 if (!NT_STATUS_IS_OK(status)) return;
131 DLIST_REMOVE(dgmsock->send_queue, req);
135 EVENT_FD_NOT_WRITEABLE(dgmsock->fde);
141 handle fd events on a nbt_dgram_socket
143 static void dgm_socket_handler(struct event_context *ev, struct fd_event *fde,
144 uint16_t flags, void *private)
146 struct nbt_dgram_socket *dgmsock = talloc_get_type(private,
147 struct nbt_dgram_socket);
148 if (flags & EVENT_FD_WRITE) {
149 dgm_socket_send(dgmsock);
151 if (flags & EVENT_FD_READ) {
152 dgm_socket_recv(dgmsock);
157 initialise a nbt_dgram_socket. The event_ctx is optional, if provided
158 then operations will use that event context
160 struct nbt_dgram_socket *nbt_dgram_socket_init(TALLOC_CTX *mem_ctx,
161 struct event_context *event_ctx,
162 struct smb_iconv_convenience *iconv_convenience)
164 struct nbt_dgram_socket *dgmsock;
167 dgmsock = talloc(mem_ctx, struct nbt_dgram_socket);
168 if (dgmsock == NULL) goto failed;
170 if (event_ctx == NULL) {
171 dgmsock->event_ctx = event_context_init(dgmsock);
173 dgmsock->event_ctx = talloc_reference(dgmsock, event_ctx);
175 if (dgmsock->event_ctx == NULL) goto failed;
177 status = socket_create("ip", SOCKET_TYPE_DGRAM, &dgmsock->sock, 0);
178 if (!NT_STATUS_IS_OK(status)) goto failed;
180 socket_set_option(dgmsock->sock, "SO_BROADCAST", "1");
182 talloc_steal(dgmsock, dgmsock->sock);
184 dgmsock->fde = event_add_fd(dgmsock->event_ctx, dgmsock,
185 socket_get_fd(dgmsock->sock), 0,
186 dgm_socket_handler, dgmsock);
188 dgmsock->send_queue = NULL;
189 dgmsock->incoming.handler = NULL;
190 dgmsock->mailslot_handlers = NULL;
191 dgmsock->iconv_convenience = iconv_convenience;
196 talloc_free(dgmsock);
202 setup a handler for generic incoming requests
204 NTSTATUS dgram_set_incoming_handler(struct nbt_dgram_socket *dgmsock,
205 void (*handler)(struct nbt_dgram_socket *,
206 struct nbt_dgram_packet *,
207 struct socket_address *),
210 dgmsock->incoming.handler = handler;
211 dgmsock->incoming.private = private;
212 EVENT_FD_READABLE(dgmsock->fde);
218 queue a datagram for send
220 NTSTATUS nbt_dgram_send(struct nbt_dgram_socket *dgmsock,
221 struct nbt_dgram_packet *packet,
222 struct socket_address *dest)
224 struct nbt_dgram_request *req;
225 NTSTATUS status = NT_STATUS_NO_MEMORY;
226 enum ndr_err_code ndr_err;
228 req = talloc(dgmsock, struct nbt_dgram_request);
229 if (req == NULL) goto failed;
232 if (talloc_reference(req, dest) == NULL) goto failed;
234 ndr_err = ndr_push_struct_blob(&req->encoded, req, dgmsock->iconv_convenience, packet,
235 (ndr_push_flags_fn_t)ndr_push_nbt_dgram_packet);
236 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
237 status = ndr_map_error2ntstatus(ndr_err);
241 DLIST_ADD_END(dgmsock->send_queue, req, struct nbt_dgram_request *);
243 EVENT_FD_WRITEABLE(dgmsock->fde);