From a90ac47d88d08dfd396e956f9e24d9fcc0de3c5d Mon Sep 17 00:00:00 2001
From: Stefan Metzmacher <metze@samba.org>
Date: Fri, 4 Oct 2019 12:11:00 +0200
Subject: [PATCH] smbXsrv_session: add a smbXsrv_session_disconnect_xconn()
 helper

This removes the connection references from the session channel
array for each session that's used on the connection.

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Guenther Deschner <gd@samba.org>
---
 source3/smbd/globals.h         |   1 +
 source3/smbd/smbXsrv_session.c | 122 +++++++++++++++++++++++++++++++++
 2 files changed, 123 insertions(+)

diff --git a/source3/smbd/globals.h b/source3/smbd/globals.h
index 2d40f080260..d3b6ac2ffe6 100644
--- a/source3/smbd/globals.h
+++ b/source3/smbd/globals.h
@@ -553,6 +553,7 @@ NTSTATUS smbXsrv_session_add_channel(struct smbXsrv_session *session,
 				     struct smbXsrv_connection *conn,
 				     NTTIME now,
 				     struct smbXsrv_channel_global0 **_c);
+NTSTATUS smbXsrv_session_disconnect_xconn(struct smbXsrv_connection *xconn);
 NTSTATUS smbXsrv_session_update(struct smbXsrv_session *session);
 struct smbXsrv_channel_global0;
 NTSTATUS smbXsrv_session_find_channel(const struct smbXsrv_session *session,
diff --git a/source3/smbd/smbXsrv_session.c b/source3/smbd/smbXsrv_session.c
index 1ebed144afd..8eaa9fdcbab 100644
--- a/source3/smbd/smbXsrv_session.c
+++ b/source3/smbd/smbXsrv_session.c
@@ -1909,6 +1909,128 @@ static int smbXsrv_session_local_traverse_cb(struct db_record *local_rec,
 	return state->caller_cb(session, state->caller_data);
 }
 
+struct smbXsrv_session_disconnect_xconn_state {
+	struct smbXsrv_connection *xconn;
+	NTSTATUS first_status;
+	int errors;
+};
+
+static int smbXsrv_session_disconnect_xconn_callback(struct db_record *local_rec,
+					       void *private_data);
+
+NTSTATUS smbXsrv_session_disconnect_xconn(struct smbXsrv_connection *xconn)
+{
+	struct smbXsrv_client *client = xconn->client;
+	struct smbXsrv_session_table *table = client->session_table;
+	struct smbXsrv_session_disconnect_xconn_state state;
+	NTSTATUS status;
+	int count = 0;
+
+	if (table == NULL) {
+		DBG_ERR("empty session_table, nothing to do.\n");
+		return NT_STATUS_OK;
+	}
+
+	ZERO_STRUCT(state);
+	state.xconn = xconn;
+
+	status = dbwrap_traverse(table->local.db_ctx,
+				 smbXsrv_session_disconnect_xconn_callback,
+				 &state, &count);
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_ERR("dbwrap_traverse() failed: %s\n",
+			nt_errstr(status));
+		return status;
+	}
+
+	if (!NT_STATUS_IS_OK(state.first_status)) {
+		DBG_ERR("count[%d] errors[%d] first[%s]\n",
+			count, state.errors,
+			nt_errstr(state.first_status));
+		return state.first_status;
+	}
+
+	return NT_STATUS_OK;
+}
+
+static int smbXsrv_session_disconnect_xconn_callback(struct db_record *local_rec,
+					       void *private_data)
+{
+	struct smbXsrv_session_disconnect_xconn_state *state =
+		(struct smbXsrv_session_disconnect_xconn_state *)private_data;
+	TDB_DATA val;
+	void *ptr = NULL;
+	struct smbXsrv_session *session = NULL;
+	struct smbXsrv_session_auth0 *a = NULL;
+	struct smbXsrv_channel_global0 *c = NULL;
+	NTSTATUS status;
+	bool need_update = false;
+
+	val = dbwrap_record_get_value(local_rec);
+	if (val.dsize != sizeof(ptr)) {
+		status = NT_STATUS_INTERNAL_ERROR;
+		if (NT_STATUS_IS_OK(state->first_status)) {
+			state->first_status = status;
+		}
+		state->errors++;
+		return 0;
+	}
+
+	memcpy(&ptr, val.dptr, val.dsize);
+	session = talloc_get_type_abort(ptr, struct smbXsrv_session);
+
+	session->db_rec = local_rec;
+
+	status = smbXsrv_session_find_auth(session, state->xconn, 0, &a);
+	if (!NT_STATUS_IS_OK(status)) {
+		a = NULL;
+	}
+	status = smbXsrv_session_find_channel(session, state->xconn, &c);
+	if (!NT_STATUS_IS_OK(status)) {
+		c = NULL;
+	}
+	if (session->global->num_channels <= 1) {
+		/*
+		 * The last channel is treated different
+		 */
+		c = NULL;
+	}
+
+	if (a != NULL) {
+		smbXsrv_session_auth0_destructor(a);
+		a->connection = NULL;
+		need_update = true;
+	}
+
+	if (c != NULL) {
+		struct smbXsrv_session_global0 *global = session->global;
+		ptrdiff_t n;
+
+		n = (c - global->channels);
+		if (n >= global->num_channels || n < 0) {
+			status = NT_STATUS_INTERNAL_ERROR;
+			if (NT_STATUS_IS_OK(state->first_status)) {
+				state->first_status = status;
+			}
+			state->errors++;
+			return 0;
+		}
+		ARRAY_DEL_ELEMENT(global->channels, n, global->num_channels);
+		global->num_channels--;
+		need_update = true;
+	}
+
+	if (need_update) {
+		status = smbXsrv_session_update(session);
+		if (NT_STATUS_IS_OK(state->first_status)) {
+			state->first_status = status;
+		}
+		state->errors++;
+	}
+
+	return 0;
+}
+
 NTSTATUS smb1srv_session_table_init(struct smbXsrv_connection *conn)
 {
 	/*
-- 
2.34.1