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)
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 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 = talloc_reference(dgmsock, 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 = 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;
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);