1 files changed, 134 insertions, 0 deletions
diff --git a/source3/libsmb/read_smb.c b/source3/libsmb/read_smb.c
new file mode 100644
index 00000000000..f530633c9f8
--- /dev/null
+++ b/source3/libsmb/read_smb.c
@@ -0,0 +1,134 @@
+/*
+   Unix SMB/CIFS implementation.
+   Infrastructure for async SMB client requests
+   Copyright (C) Volker Lendecke 2008
+
+   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/async_req/async_sock.h"
+#include "read_smb.h"
+#include "lib/util/tevent_unix.h"
+
+/*
+ * Read an smb packet asynchronously, discard keepalives
+ */
+
+struct read_smb_state {
+	struct tevent_context *ev;
+	int fd;
+	uint8_t *buf;
+};
+
+static ssize_t read_smb_more(uint8_t *buf, size_t buflen, void *private_data);
+static void read_smb_done(struct tevent_req *subreq);
+
+struct tevent_req *read_smb_send(TALLOC_CTX *mem_ctx,
+				 struct tevent_context *ev,
+				 int fd)
+{
+	struct tevent_req *result, *subreq;
+	struct read_smb_state *state;
+
+	result = tevent_req_create(mem_ctx, &state, struct read_smb_state);
+	if (result == NULL) {
+		return NULL;
+	}
+	state->ev = ev;
+	state->fd = fd;
+
+	subreq = read_packet_send(state, ev, fd, 4, read_smb_more, NULL);
+	if (subreq == NULL) {
+		goto fail;
+	}
+	tevent_req_set_callback(subreq, read_smb_done, result);
+	return result;
+ fail:
+	TALLOC_FREE(result);
+	return NULL;
+}
+
+static ssize_t read_smb_more(uint8_t *buf, size_t buflen, void *private_data)
+{
+	if (buflen > 4) {
+		return 0;	/* We've been here, we're done */
+	}
+	return smb_len_large(buf);
+}
+
+static void read_smb_done(struct tevent_req *subreq)
+{
+	struct tevent_req *req = tevent_req_callback_data(
+		subreq, struct tevent_req);
+	struct read_smb_state *state = tevent_req_data(
+		req, struct read_smb_state);
+	ssize_t len;
+	int err;
+
+	len = read_packet_recv(subreq, state, &state->buf, &err);
+	TALLOC_FREE(subreq);
+	if (len == -1) {
+		tevent_req_error(req, err);
+		return;
+	}
+
+	if (CVAL(state->buf, 0) == SMBkeepalive) {
+		subreq = read_packet_send(state, state->ev, state->fd, 4,
+					  read_smb_more, NULL);
+		if (tevent_req_nomem(subreq, req)) {
+			return;
+		}
+		tevent_req_set_callback(subreq, read_smb_done, req);
+		return;
+	}
+	tevent_req_done(req);
+}
+
+ssize_t read_smb_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
+		      uint8_t **pbuf, int *perrno)
+{
+	struct read_smb_state *state = tevent_req_data(
+		req, struct read_smb_state);
+
+	if (tevent_req_is_unix_error(req, perrno)) {
+		return -1;
+	}
+	*pbuf = talloc_move(mem_ctx, &state->buf);
+	return talloc_get_size(*pbuf);
+}
+
+ssize_t read_smb(int fd, TALLOC_CTX *mem_ctx, uint8_t **pbuf, int *perrno)
+{
+	TALLOC_CTX *frame = talloc_stackframe();
+	struct event_context *ev;
+	struct tevent_req *req;
+	ssize_t ret = -1;
+
+	ev = event_context_init(frame);
+	if (ev == NULL) {
+		goto fail;
+	}
+	req = read_smb_send(frame, ev, fd);
+	if (req == NULL) {
+		goto fail;
+	}
+	if (!tevent_req_poll(req, ev)) {
+		goto fail;
+	}
+	ret = read_smb_recv(req, mem_ctx, pbuf, perrno);
+ fail:
+	TALLOC_FREE(frame);
+	return ret;
+}