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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-05 17:47:29 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-05 17:47:29 +0000
commit4f5791ebd03eaec1c7da0865a383175b05102712 (patch)
tree8ce7b00f7a76baa386372422adebbe64510812d4 /source3/libsmb/unexpected.c
parentInitial commit. (diff)
downloadsamba-4f5791ebd03eaec1c7da0865a383175b05102712.tar.xz
samba-4f5791ebd03eaec1c7da0865a383175b05102712.zip
Adding upstream version 2:4.17.12+dfsg.upstream/2%4.17.12+dfsgupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'source3/libsmb/unexpected.c')
-rw-r--r--source3/libsmb/unexpected.c749
1 files changed, 749 insertions, 0 deletions
diff --git a/source3/libsmb/unexpected.c b/source3/libsmb/unexpected.c
new file mode 100644
index 0000000..ced4696
--- /dev/null
+++ b/source3/libsmb/unexpected.c
@@ -0,0 +1,749 @@
+/*
+ Unix SMB/CIFS implementation.
+ handle unexpected packets
+ Copyright (C) Andrew Tridgell 2000
+
+ 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 "libsmb/unexpected.h"
+#include "../lib/util/tevent_ntstatus.h"
+#include "lib/util_tsock.h"
+#include "libsmb/nmblib.h"
+#include "lib/tsocket/tsocket.h"
+#include "lib/util/sys_rw.h"
+
+static const char *nmbd_socket_dir(void)
+{
+ return lp_parm_const_string(-1, "nmbd", "socket dir",
+ get_dyn_NMBDSOCKETDIR());
+}
+
+struct nb_packet_query {
+ enum packet_type type;
+ size_t mailslot_namelen;
+ int trn_id;
+};
+
+struct nb_packet_client;
+
+struct nb_packet_server {
+ struct tevent_context *ev;
+ int listen_sock;
+ struct tevent_fd *listen_fde;
+ int max_clients;
+ int num_clients;
+ struct nb_packet_client *clients;
+};
+
+struct nb_packet_client {
+ struct nb_packet_client *prev, *next;
+ struct nb_packet_server *server;
+
+ enum packet_type type;
+ int trn_id;
+ char *mailslot_name;
+
+ struct {
+ uint8_t byte;
+ struct iovec iov[1];
+ } ack;
+
+ struct tstream_context *sock;
+ struct tevent_queue *out_queue;
+};
+
+static int nb_packet_server_destructor(struct nb_packet_server *s);
+static void nb_packet_server_listener(struct tevent_context *ev,
+ struct tevent_fd *fde,
+ uint16_t flags,
+ void *private_data);
+
+NTSTATUS nb_packet_server_create(TALLOC_CTX *mem_ctx,
+ struct tevent_context *ev,
+ int max_clients,
+ struct nb_packet_server **presult)
+{
+ struct nb_packet_server *result;
+ NTSTATUS status;
+ int rc;
+
+ result = talloc_zero(mem_ctx, struct nb_packet_server);
+ if (result == NULL) {
+ status = NT_STATUS_NO_MEMORY;
+ goto fail;
+ }
+ result->ev = ev;
+ result->max_clients = max_clients;
+
+ result->listen_sock = create_pipe_sock(
+ nmbd_socket_dir(), "unexpected", 0755);
+ if (result->listen_sock == -1) {
+ status = map_nt_error_from_unix(errno);
+ goto fail;
+ }
+ rc = listen(result->listen_sock, 5);
+ if (rc < 0) {
+ status = map_nt_error_from_unix(errno);
+ goto fail;
+ }
+ talloc_set_destructor(result, nb_packet_server_destructor);
+
+ result->listen_fde = tevent_add_fd(ev, result,
+ result->listen_sock,
+ TEVENT_FD_READ,
+ nb_packet_server_listener,
+ result);
+ if (result->listen_fde == NULL) {
+ status = NT_STATUS_NO_MEMORY;
+ goto fail;
+ }
+
+ *presult = result;
+ return NT_STATUS_OK;
+fail:
+ TALLOC_FREE(result);
+ return status;
+}
+
+static int nb_packet_server_destructor(struct nb_packet_server *s)
+{
+ TALLOC_FREE(s->listen_fde);
+
+ if (s->listen_sock != -1) {
+ close(s->listen_sock);
+ s->listen_sock = -1;
+ }
+ return 0;
+}
+
+static int nb_packet_client_destructor(struct nb_packet_client *c);
+static ssize_t nb_packet_client_more(uint8_t *buf, size_t buflen,
+ void *private_data);
+static void nb_packet_got_query(struct tevent_req *req);
+static void nb_packet_client_ack_done(struct tevent_req *req);
+static void nb_packet_client_read_done(struct tevent_req *req);
+
+static void nb_packet_server_listener(struct tevent_context *ev,
+ struct tevent_fd *fde,
+ uint16_t flags,
+ void *private_data)
+{
+ struct nb_packet_server *server = talloc_get_type_abort(
+ private_data, struct nb_packet_server);
+ struct nb_packet_client *client;
+ struct tevent_req *req;
+ struct sockaddr_un sunaddr;
+ socklen_t len;
+ int sock;
+ int ret;
+
+ len = sizeof(sunaddr);
+
+ sock = accept(server->listen_sock, (struct sockaddr *)(void *)&sunaddr,
+ &len);
+ if (sock == -1) {
+ return;
+ }
+ smb_set_close_on_exec(sock);
+ DEBUG(6,("accepted socket %d\n", sock));
+
+ client = talloc_zero(server, struct nb_packet_client);
+ if (client == NULL) {
+ DEBUG(10, ("talloc failed\n"));
+ close(sock);
+ return;
+ }
+ ret = tstream_bsd_existing_socket(client, sock, &client->sock);
+ if (ret != 0) {
+ DEBUG(10, ("tstream_bsd_existing_socket failed\n"));
+ TALLOC_FREE(client);
+ close(sock);
+ return;
+ }
+
+ client->server = server;
+
+ client->out_queue = tevent_queue_create(
+ client, "unexpected packet output");
+ if (client->out_queue == NULL) {
+ DEBUG(10, ("tevent_queue_create failed\n"));
+ TALLOC_FREE(client);
+ return;
+ }
+
+ req = tstream_read_packet_send(client, ev, client->sock,
+ sizeof(struct nb_packet_query),
+ nb_packet_client_more, NULL);
+ if (req == NULL) {
+ DEBUG(10, ("tstream_read_packet_send failed\n"));
+ TALLOC_FREE(client);
+ return;
+ }
+ tevent_req_set_callback(req, nb_packet_got_query, client);
+
+ DLIST_ADD(server->clients, client);
+ server->num_clients += 1;
+
+ talloc_set_destructor(client, nb_packet_client_destructor);
+
+ if (server->num_clients > server->max_clients) {
+ DEBUG(10, ("Too many clients, dropping oldest\n"));
+
+ /*
+ * no TALLOC_FREE here, don't mess with the list structs
+ */
+ talloc_free(server->clients->prev);
+ }
+}
+
+static ssize_t nb_packet_client_more(uint8_t *buf, size_t buflen,
+ void *private_data)
+{
+ struct nb_packet_query q;
+ if (buflen > sizeof(struct nb_packet_query)) {
+ return 0;
+ }
+ /* Take care of alignment */
+ memcpy(&q, buf, sizeof(q));
+ if (q.mailslot_namelen > 1024) {
+ DEBUG(10, ("Got invalid mailslot namelen %d\n",
+ (int)q.mailslot_namelen));
+ return -1;
+ }
+ return q.mailslot_namelen;
+}
+
+static int nb_packet_client_destructor(struct nb_packet_client *c)
+{
+ tevent_queue_stop(c->out_queue);
+ TALLOC_FREE(c->sock);
+
+ DLIST_REMOVE(c->server->clients, c);
+ c->server->num_clients -= 1;
+ return 0;
+}
+
+static void nb_packet_got_query(struct tevent_req *req)
+{
+ struct nb_packet_client *client = tevent_req_callback_data(
+ req, struct nb_packet_client);
+ struct nb_packet_query q;
+ uint8_t *buf;
+ ssize_t nread;
+ int err;
+
+ nread = tstream_read_packet_recv(req, talloc_tos(), &buf, &err);
+ TALLOC_FREE(req);
+ if (nread < (ssize_t)sizeof(struct nb_packet_query)) {
+ DEBUG(10, ("read_packet_recv returned %d (%s)\n",
+ (int)nread,
+ (nread == -1) ? strerror(err) : "wrong length"));
+ TALLOC_FREE(client);
+ return;
+ }
+
+ /* Take care of alignment */
+ memcpy(&q, buf, sizeof(q));
+
+ if ((size_t)nread !=
+ sizeof(struct nb_packet_query) + q.mailslot_namelen) {
+ DEBUG(10, ("nb_packet_got_query: Invalid mailslot namelength\n"));
+ TALLOC_FREE(client);
+ return;
+ }
+
+ client->trn_id = q.trn_id;
+ client->type = q.type;
+ if (q.mailslot_namelen > 0) {
+ client->mailslot_name = talloc_strndup(
+ client, (char *)buf + sizeof(q),
+ q.mailslot_namelen);
+ if (client->mailslot_name == NULL) {
+ TALLOC_FREE(client);
+ return;
+ }
+ }
+
+ client->ack.byte = 0;
+ client->ack.iov[0].iov_base = &client->ack.byte;
+ client->ack.iov[0].iov_len = 1;
+ req = tstream_writev_queue_send(client, client->server->ev,
+ client->sock,
+ client->out_queue,
+ client->ack.iov, 1);
+ if (req == NULL) {
+ DEBUG(10, ("tstream_writev_queue_send failed\n"));
+ TALLOC_FREE(client);
+ return;
+ }
+ tevent_req_set_callback(req, nb_packet_client_ack_done, client);
+
+ req = tstream_read_packet_send(client, client->server->ev,
+ client->sock, 1, NULL, NULL);
+ if (req == NULL) {
+ DEBUG(10, ("Could not activate reader for client exit "
+ "detection\n"));
+ TALLOC_FREE(client);
+ return;
+ }
+ tevent_req_set_callback(req, nb_packet_client_read_done,
+ client);
+}
+
+static void nb_packet_client_ack_done(struct tevent_req *req)
+{
+ struct nb_packet_client *client = tevent_req_callback_data(
+ req, struct nb_packet_client);
+ ssize_t nwritten;
+ int err;
+
+ nwritten = tstream_writev_queue_recv(req, &err);
+
+ TALLOC_FREE(req);
+
+ if (nwritten == -1) {
+ DEBUG(10, ("tstream_writev_queue_recv failed: %s\n",
+ strerror(err)));
+ TALLOC_FREE(client);
+ return;
+ }
+}
+
+static void nb_packet_client_read_done(struct tevent_req *req)
+{
+ struct nb_packet_client *client = tevent_req_callback_data(
+ req, struct nb_packet_client);
+ ssize_t nread;
+ uint8_t *buf;
+ int err;
+
+ nread = tstream_read_packet_recv(req, talloc_tos(), &buf, &err);
+ TALLOC_FREE(req);
+ if (nread == 1) {
+ DEBUG(10, ("Protocol error, received data on write-only "
+ "unexpected socket: 0x%2.2x\n", (*buf)));
+ }
+ TALLOC_FREE(client);
+}
+
+static void nb_packet_client_send(struct nb_packet_client *client,
+ struct packet_struct *p);
+
+void nb_packet_dispatch(struct nb_packet_server *server,
+ struct packet_struct *p)
+{
+ struct nb_packet_client *c;
+ uint16_t trn_id;
+
+ switch (p->packet_type) {
+ case NMB_PACKET:
+ trn_id = p->packet.nmb.header.name_trn_id;
+ break;
+ case DGRAM_PACKET:
+ trn_id = p->packet.dgram.header.dgm_id;
+ break;
+ default:
+ DEBUG(10, ("Got invalid packet type %d\n",
+ (int)p->packet_type));
+ return;
+ }
+ for (c = server->clients; c != NULL; c = c->next) {
+
+ if (c->type != p->packet_type) {
+ DEBUG(10, ("client expects packet %d, got %d\n",
+ c->type, p->packet_type));
+ continue;
+ }
+
+ if (p->packet_type == NMB_PACKET) {
+ /*
+ * See if the client specified transaction
+ * ID. Filter if it did.
+ */
+ if ((c->trn_id != -1) &&
+ (c->trn_id != trn_id)) {
+ DEBUG(10, ("client expects trn %d, got %d\n",
+ c->trn_id, trn_id));
+ continue;
+ }
+ } else {
+ /*
+ * See if the client specified a mailslot
+ * name. Filter if it did.
+ */
+ if ((c->mailslot_name != NULL) &&
+ !match_mailslot_name(p, c->mailslot_name)) {
+ continue;
+ }
+ }
+ nb_packet_client_send(c, p);
+ }
+}
+
+struct nb_packet_client_header {
+ size_t len;
+ enum packet_type type;
+ time_t timestamp;
+ struct in_addr ip;
+ int port;
+};
+
+struct nb_packet_client_state {
+ struct nb_packet_client *client;
+ struct iovec iov[2];
+ struct nb_packet_client_header hdr;
+ char buf[1024];
+};
+
+static void nb_packet_client_send_done(struct tevent_req *req);
+
+static void nb_packet_client_send(struct nb_packet_client *client,
+ struct packet_struct *p)
+{
+ struct nb_packet_client_state *state;
+ struct tevent_req *req;
+
+ if (tevent_queue_length(client->out_queue) > 10) {
+ /*
+ * Skip clients that don't listen anyway, some form of DoS
+ * protection
+ */
+ return;
+ }
+
+ state = talloc_zero(client, struct nb_packet_client_state);
+ if (state == NULL) {
+ DEBUG(10, ("talloc failed\n"));
+ return;
+ }
+
+ state->client = client;
+
+ state->hdr.ip = p->ip;
+ state->hdr.port = p->port;
+ state->hdr.timestamp = p->timestamp;
+ state->hdr.type = p->packet_type;
+ state->hdr.len = build_packet(state->buf, sizeof(state->buf), p);
+
+ state->iov[0].iov_base = (char *)&state->hdr;
+ state->iov[0].iov_len = sizeof(state->hdr);
+ state->iov[1].iov_base = state->buf;
+ state->iov[1].iov_len = state->hdr.len;
+
+ req = tstream_writev_queue_send(state, client->server->ev,
+ client->sock,
+ client->out_queue,
+ state->iov, 2);
+ if (req == NULL) {
+ DEBUG(10, ("tstream_writev_queue_send failed\n"));
+ return;
+ }
+ tevent_req_set_callback(req, nb_packet_client_send_done, state);
+}
+
+static void nb_packet_client_send_done(struct tevent_req *req)
+{
+ struct nb_packet_client_state *state = tevent_req_callback_data(
+ req, struct nb_packet_client_state);
+ struct nb_packet_client *client = state->client;
+ ssize_t nwritten;
+ int err;
+
+ nwritten = tstream_writev_queue_recv(req, &err);
+
+ TALLOC_FREE(req);
+ TALLOC_FREE(state);
+
+ if (nwritten == -1) {
+ DEBUG(10, ("tstream_writev_queue failed: %s\n", strerror(err)));
+ TALLOC_FREE(client);
+ return;
+ }
+}
+
+struct nb_packet_reader {
+ struct tstream_context *sock;
+};
+
+struct nb_packet_reader_state {
+ struct tevent_context *ev;
+ struct nb_packet_query query;
+ const char *mailslot_name;
+ struct iovec iov[2];
+ struct nb_packet_reader *reader;
+};
+
+static void nb_packet_reader_connected(struct tevent_req *subreq);
+static void nb_packet_reader_sent_query(struct tevent_req *subreq);
+static void nb_packet_reader_got_ack(struct tevent_req *subreq);
+
+struct tevent_req *nb_packet_reader_send(TALLOC_CTX *mem_ctx,
+ struct tevent_context *ev,
+ enum packet_type type,
+ int trn_id,
+ const char *mailslot_name)
+{
+ struct tevent_req *req, *subreq;
+ struct nb_packet_reader_state *state;
+ struct tsocket_address *laddr;
+ char *rpath;
+ struct tsocket_address *raddr;
+ int ret;
+
+ req = tevent_req_create(mem_ctx, &state,
+ struct nb_packet_reader_state);
+ if (req == NULL) {
+ return NULL;
+ }
+ state->ev = ev;
+ state->query.trn_id = trn_id;
+ state->query.type = type;
+ state->mailslot_name = mailslot_name;
+
+ if (mailslot_name != NULL) {
+ state->query.mailslot_namelen = strlen(mailslot_name);
+ }
+
+ state->reader = talloc_zero(state, struct nb_packet_reader);
+ if (tevent_req_nomem(state->reader, req)) {
+ return tevent_req_post(req, ev);
+ }
+
+ ret = tsocket_address_unix_from_path(state, NULL, &laddr);
+ if (ret != 0) {
+ tevent_req_nterror(req, map_nt_error_from_unix(errno));
+ return tevent_req_post(req, ev);
+ }
+ rpath = talloc_asprintf(state, "%s/%s", nmbd_socket_dir(),
+ "unexpected");
+ if (tevent_req_nomem(rpath, req)) {
+ return tevent_req_post(req, ev);
+ }
+ ret = tsocket_address_unix_from_path(state, rpath, &raddr);
+ if (ret != 0) {
+ tevent_req_nterror(req, map_nt_error_from_unix(errno));
+ return tevent_req_post(req, ev);
+ }
+
+ subreq = tstream_unix_connect_send(state, ev, laddr, raddr);
+ if (tevent_req_nomem(subreq, req)) {
+ return tevent_req_post(req, ev);
+ }
+ tevent_req_set_callback(subreq, nb_packet_reader_connected, req);
+ return req;
+}
+
+static void nb_packet_reader_connected(struct tevent_req *subreq)
+{
+ struct tevent_req *req = tevent_req_callback_data(
+ subreq, struct tevent_req);
+ struct nb_packet_reader_state *state = tevent_req_data(
+ req, struct nb_packet_reader_state);
+ int res, err;
+ int num_iovecs = 1;
+
+ res = tstream_unix_connect_recv(subreq, &err, state->reader,
+ &state->reader->sock);
+ TALLOC_FREE(subreq);
+ if (res == -1) {
+ DEBUG(10, ("tstream_unix_connect failed: %s\n", strerror(err)));
+ tevent_req_nterror(req, map_nt_error_from_unix(err));
+ return;
+ }
+
+ state->iov[0].iov_base = (char *)&state->query;
+ state->iov[0].iov_len = sizeof(state->query);
+
+ if (state->mailslot_name != NULL) {
+ num_iovecs = 2;
+ state->iov[1].iov_base = discard_const_p(
+ char, state->mailslot_name);
+ state->iov[1].iov_len = state->query.mailslot_namelen;
+ }
+
+ subreq = tstream_writev_send(state, state->ev, state->reader->sock,
+ state->iov, num_iovecs);
+ if (tevent_req_nomem(subreq, req)) {
+ return;
+ }
+ tevent_req_set_callback(subreq, nb_packet_reader_sent_query, req);
+}
+
+static void nb_packet_reader_sent_query(struct tevent_req *subreq)
+{
+ struct tevent_req *req = tevent_req_callback_data(
+ subreq, struct tevent_req);
+ struct nb_packet_reader_state *state = tevent_req_data(
+ req, struct nb_packet_reader_state);
+ ssize_t written;
+ int err;
+
+ written = tstream_writev_recv(subreq, &err);
+ TALLOC_FREE(subreq);
+ if (written == -1) {
+ tevent_req_nterror(req, map_nt_error_from_unix(err));
+ return;
+ }
+ if ((size_t)written !=
+ sizeof(state->query) + state->query.mailslot_namelen) {
+ tevent_req_nterror(req, NT_STATUS_UNEXPECTED_IO_ERROR);
+ return;
+ }
+ subreq = tstream_read_packet_send(state, state->ev,
+ state->reader->sock,
+ 1, NULL, NULL);
+ if (tevent_req_nomem(subreq, req)) {
+ return;
+ }
+ tevent_req_set_callback(subreq, nb_packet_reader_got_ack, req);
+}
+
+static void nb_packet_reader_got_ack(struct tevent_req *subreq)
+{
+ struct tevent_req *req = tevent_req_callback_data(
+ subreq, struct tevent_req);
+ struct nb_packet_reader_state *state = tevent_req_data(
+ req, struct nb_packet_reader_state);
+ ssize_t nread;
+ int err;
+ uint8_t *buf;
+
+ nread = tstream_read_packet_recv(subreq, state, &buf, &err);
+ TALLOC_FREE(subreq);
+ if (nread == -1) {
+ DEBUG(10, ("read_packet_recv returned %s\n",
+ strerror(err)));
+ tevent_req_nterror(req, map_nt_error_from_unix(err));
+ return;
+ }
+ if (nread != 1) {
+ DBG_DEBUG("read = %zd, expected 1\n", nread);
+ tevent_req_nterror(req, NT_STATUS_UNEXPECTED_IO_ERROR);
+ return;
+ }
+ tevent_req_done(req);
+}
+
+NTSTATUS nb_packet_reader_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
+ struct nb_packet_reader **preader)
+{
+ struct nb_packet_reader_state *state = tevent_req_data(
+ req, struct nb_packet_reader_state);
+ NTSTATUS status;
+
+ if (tevent_req_is_nterror(req, &status)) {
+ tevent_req_received(req);
+ return status;
+ }
+ *preader = talloc_move(mem_ctx, &state->reader);
+ tevent_req_received(req);
+ return NT_STATUS_OK;
+}
+
+struct nb_packet_read_state {
+ struct nb_packet_client_header hdr;
+ uint8_t *buf;
+ size_t buflen;
+};
+
+static ssize_t nb_packet_read_more(uint8_t *buf, size_t buflen, void *p);
+static void nb_packet_read_done(struct tevent_req *subreq);
+
+struct tevent_req *nb_packet_read_send(TALLOC_CTX *mem_ctx,
+ struct tevent_context *ev,
+ struct nb_packet_reader *reader)
+{
+ struct tevent_req *req, *subreq;
+ struct nb_packet_read_state *state;
+
+ req = tevent_req_create(mem_ctx, &state, struct nb_packet_read_state);
+ if (req == NULL) {
+ return NULL;
+ }
+ subreq = tstream_read_packet_send(state, ev, reader->sock,
+ sizeof(struct nb_packet_client_header),
+ nb_packet_read_more, state);
+ if (tevent_req_nomem(subreq, req)) {
+ return tevent_req_post(req, ev);
+ }
+ tevent_req_set_callback(subreq, nb_packet_read_done, req);
+ return req;
+}
+
+static ssize_t nb_packet_read_more(uint8_t *buf, size_t buflen, void *p)
+{
+ struct nb_packet_read_state *state = talloc_get_type_abort(
+ p, struct nb_packet_read_state);
+
+ if (buflen > sizeof(struct nb_packet_client_header)) {
+ /*
+ * Been here, done
+ */
+ return 0;
+ }
+ memcpy(&state->hdr, buf, sizeof(struct nb_packet_client_header));
+ return state->hdr.len;
+}
+
+static void nb_packet_read_done(struct tevent_req *subreq)
+{
+ struct tevent_req *req = tevent_req_callback_data(
+ subreq, struct tevent_req);
+ struct nb_packet_read_state *state = tevent_req_data(
+ req, struct nb_packet_read_state);
+ ssize_t nread;
+ int err;
+
+ nread = tstream_read_packet_recv(subreq, state, &state->buf, &err);
+ if (nread == -1) {
+ tevent_req_nterror(req, map_nt_error_from_unix(err));
+ return;
+ }
+ state->buflen = nread;
+ tevent_req_done(req);
+}
+
+NTSTATUS nb_packet_read_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
+ struct packet_struct **ppacket)
+{
+ struct nb_packet_read_state *state = tevent_req_data(
+ req, struct nb_packet_read_state);
+ struct nb_packet_client_header hdr;
+ struct packet_struct *packet;
+ NTSTATUS status;
+
+ if (tevent_req_is_nterror(req, &status)) {
+ tevent_req_received(req);
+ return status;
+ }
+
+ memcpy(&hdr, state->buf, sizeof(hdr));
+
+ packet = parse_packet_talloc(
+ mem_ctx,
+ (char *)state->buf + sizeof(struct nb_packet_client_header),
+ state->buflen - sizeof(struct nb_packet_client_header),
+ state->hdr.type, state->hdr.ip, state->hdr.port);
+ if (packet == NULL) {
+ tevent_req_received(req);
+ return NT_STATUS_INVALID_NETWORK_RESPONSE;
+ }
+
+ *ppacket = packet;
+ tevent_req_received(req);
+ return NT_STATUS_OK;
+}