diff options
Diffstat (limited to 'source4/libcli/dgram/dgramsocket.c')
| -rw-r--r-- | source4/libcli/dgram/dgramsocket.c | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/source4/libcli/dgram/dgramsocket.c b/source4/libcli/dgram/dgramsocket.c new file mode 100644 index 0000000..154a667 --- /dev/null +++ b/source4/libcli/dgram/dgramsocket.c @@ -0,0 +1,242 @@ +/* + Unix SMB/CIFS implementation. + + low level socket handling for nbt dgram requests (UDP138) + + Copyright (C) Andrew Tridgell 2005 + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +#include "includes.h" +#include "lib/events/events.h" +#include "../lib/util/dlinklist.h" +#include "libcli/dgram/libdgram.h" +#include "lib/socket/socket.h" +#include "librpc/gen_ndr/ndr_nbt.h" + + +/* + handle recv events on a nbt dgram socket +*/ +static void dgm_socket_recv(struct nbt_dgram_socket *dgmsock) +{ + TALLOC_CTX *tmp_ctx = talloc_new(dgmsock); + NTSTATUS status; + struct socket_address *src; + DATA_BLOB blob; + size_t nread, dsize; + struct nbt_dgram_packet *packet; + const char *mailslot_name; + enum ndr_err_code ndr_err; + + status = socket_pending(dgmsock->sock, &dsize); + if (!NT_STATUS_IS_OK(status)) { + talloc_free(tmp_ctx); + return; + } + + blob = data_blob_talloc(tmp_ctx, NULL, dsize); + if ((dsize != 0) && (blob.data == NULL)) { + talloc_free(tmp_ctx); + return; + } + + status = socket_recvfrom(dgmsock->sock, blob.data, blob.length, &nread, + tmp_ctx, &src); + if (!NT_STATUS_IS_OK(status)) { + talloc_free(tmp_ctx); + return; + } + blob.length = nread; + + DEBUG(5,("Received dgram packet of length %d from %s:%d\n", + (int)blob.length, src->addr, src->port)); + + packet = talloc(tmp_ctx, struct nbt_dgram_packet); + if (packet == NULL) { + talloc_free(tmp_ctx); + return; + } + + /* parse the request */ + ndr_err = ndr_pull_struct_blob(&blob, packet, packet, + (ndr_pull_flags_fn_t)ndr_pull_nbt_dgram_packet); + if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) { + status = ndr_map_error2ntstatus(ndr_err); + DEBUG(2,("Failed to parse incoming NBT DGRAM packet - %s\n", + nt_errstr(status))); + talloc_free(tmp_ctx); + return; + } + + /* if this is a mailslot message, then see if we can dispatch it to a handler */ + mailslot_name = dgram_mailslot_name(packet); + if (mailslot_name) { + struct dgram_mailslot_handler *dgmslot; + dgmslot = dgram_mailslot_find(dgmsock, mailslot_name); + if (dgmslot) { + dgmslot->handler(dgmslot, packet, src); + } else { + DEBUG(2,("No mailslot handler for '%s'\n", mailslot_name)); + } + } else { + /* dispatch if there is a general handler */ + if (dgmsock->incoming.handler) { + dgmsock->incoming.handler(dgmsock, packet, src); + } + } + + talloc_free(tmp_ctx); +} + + +/* + handle send events on a nbt dgram socket +*/ +static void dgm_socket_send(struct nbt_dgram_socket *dgmsock) +{ + struct nbt_dgram_request *req; + NTSTATUS status; + + while ((req = dgmsock->send_queue)) { + size_t len; + + len = req->encoded.length; + status = socket_sendto(dgmsock->sock, &req->encoded, &len, + req->dest); + if (NT_STATUS_IS_ERR(status)) { + DEBUG(3,("Failed to send datagram of length %u to %s:%d: %s\n", + (unsigned)req->encoded.length, req->dest->addr, req->dest->port, + nt_errstr(status))); + DLIST_REMOVE(dgmsock->send_queue, req); + talloc_free(req); + continue; + } + + if (!NT_STATUS_IS_OK(status)) return; + + DLIST_REMOVE(dgmsock->send_queue, req); + talloc_free(req); + } + + TEVENT_FD_NOT_WRITEABLE(dgmsock->fde); + return; +} + + +/* + handle fd events on a nbt_dgram_socket +*/ +static void dgm_socket_handler(struct tevent_context *ev, struct tevent_fd *fde, + uint16_t flags, void *private_data) +{ + struct nbt_dgram_socket *dgmsock = talloc_get_type(private_data, + struct nbt_dgram_socket); + if (flags & TEVENT_FD_WRITE) { + dgm_socket_send(dgmsock); + } + if (flags & TEVENT_FD_READ) { + dgm_socket_recv(dgmsock); + } +} + +/* + initialise a nbt_dgram_socket. The event_ctx is optional, if provided + then operations will use that event context +*/ +struct nbt_dgram_socket *nbt_dgram_socket_init(TALLOC_CTX *mem_ctx, + struct tevent_context *event_ctx) +{ + struct nbt_dgram_socket *dgmsock; + NTSTATUS status; + + dgmsock = talloc(mem_ctx, struct nbt_dgram_socket); + if (dgmsock == NULL) goto failed; + + dgmsock->event_ctx = event_ctx; + if (dgmsock->event_ctx == NULL) goto failed; + + status = socket_create(dgmsock, "ip", SOCKET_TYPE_DGRAM, + &dgmsock->sock, 0); + if (!NT_STATUS_IS_OK(status)) goto failed; + + socket_set_option(dgmsock->sock, "SO_BROADCAST", "1"); + + dgmsock->fde = tevent_add_fd(dgmsock->event_ctx, dgmsock, + socket_get_fd(dgmsock->sock), 0, + dgm_socket_handler, dgmsock); + + dgmsock->send_queue = NULL; + dgmsock->incoming.handler = NULL; + dgmsock->mailslot_handlers = NULL; + + return dgmsock; + +failed: + talloc_free(dgmsock); + return NULL; +} + + +/* + setup a handler for generic incoming requests +*/ +NTSTATUS dgram_set_incoming_handler(struct nbt_dgram_socket *dgmsock, + void (*handler)(struct nbt_dgram_socket *, + struct nbt_dgram_packet *, + struct socket_address *), + void *private_data) +{ + dgmsock->incoming.handler = handler; + dgmsock->incoming.private_data = private_data; + TEVENT_FD_READABLE(dgmsock->fde); + return NT_STATUS_OK; +} + + +/* + queue a datagram for send +*/ +NTSTATUS nbt_dgram_send(struct nbt_dgram_socket *dgmsock, + struct nbt_dgram_packet *packet, + struct socket_address *dest) +{ + struct nbt_dgram_request *req; + NTSTATUS status = NT_STATUS_NO_MEMORY; + enum ndr_err_code ndr_err; + + req = talloc(dgmsock, struct nbt_dgram_request); + if (req == NULL) goto failed; + + req->dest = dest; + if (talloc_reference(req, dest) == NULL) goto failed; + + ndr_err = ndr_push_struct_blob(&req->encoded, req, packet, + (ndr_push_flags_fn_t)ndr_push_nbt_dgram_packet); + if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) { + status = ndr_map_error2ntstatus(ndr_err); + goto failed; + } + + DLIST_ADD_END(dgmsock->send_queue, req); + + TEVENT_FD_WRITEABLE(dgmsock->fde); + + return NT_STATUS_OK; + +failed: + talloc_free(req); + return status; +} |