From: Ralph Boehme <slow@samba.org>
Date: Mon, 6 Jan 2020 07:19:18 +0000 (+0100)
Subject: smbd: add get_valid_smbXsrv_session()
X-Git-Tag: ldb-2.1.0~33
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dd9735b1da73b6c27feda32230e3fc843746fd2b;p=thirdparty%2Fsamba.git

smbd: add get_valid_smbXsrv_session()

In memory of get_valid_user_struct() and functionally equivalent it only returns
the session if session setup was successfully completed and
session->global->auth_session_info is valid.

This function is similar to smbXsrv_session_local_lookup() and it's wrappers,
but it doesn't implement the state checks of those. get_valid_smbXsrv_session()
is NOT meant to be called to validate the session wire-id of incoming SMB
requests, it MUST only be used in later internal processing where the session
wire-id has already been validated.

Signed-off-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
---

diff --git a/source3/smbd/globals.h b/source3/smbd/globals.h
index d91d174a776..57300dd02ae 100644
--- a/source3/smbd/globals.h
+++ b/source3/smbd/globals.h
@@ -583,6 +583,9 @@ NTSTATUS smb2srv_session_lookup_conn(struct smbXsrv_connection *conn,
 NTSTATUS smb2srv_session_lookup_client(struct smbXsrv_client *client,
 				       uint64_t session_id, NTTIME now,
 				       struct smbXsrv_session **session);
+NTSTATUS get_valid_smbXsrv_session(struct smbXsrv_client *client,
+				   uint64_t session_wire_id,
+				   struct smbXsrv_session **session);
 struct smbXsrv_session_global0;
 NTSTATUS smbXsrv_session_global_traverse(
 			int (*fn)(struct smbXsrv_session_global0 *, void *),
diff --git a/source3/smbd/smbXsrv_session.c b/source3/smbd/smbXsrv_session.c
index 14a2d6c8ca2..b2d36d380be 100644
--- a/source3/smbd/smbXsrv_session.c
+++ b/source3/smbd/smbXsrv_session.c
@@ -1895,6 +1895,60 @@ NTSTATUS smbXsrv_session_info_lookup(struct smbXsrv_client *client,
 	return NT_STATUS_OK;
 }
 
+/*
+ * In memory of get_valid_user_struct()
+ *
+ * This function is similar to smbXsrv_session_local_lookup() and it's wrappers,
+ * but it doesn't implement the state checks of
+ * those. get_valid_smbXsrv_session() is NOT meant to be called to validate the
+ * session wire-id of incoming SMB requests, it MUST only be used in later
+ * internal processing where the session wire-id has already been validated.
+ */
+NTSTATUS get_valid_smbXsrv_session(struct smbXsrv_client *client,
+				   uint64_t session_wire_id,
+				   struct smbXsrv_session **session)
+{
+	struct smbXsrv_session_table *table = client->session_table;
+	uint8_t key_buf[SMBXSRV_SESSION_LOCAL_TDB_KEY_SIZE];
+	struct smbXsrv_session_local_fetch_state state = {
+		.session = NULL,
+		.status = NT_STATUS_INTERNAL_ERROR,
+	};
+	TDB_DATA key;
+	NTSTATUS status;
+
+	if (session_wire_id == 0) {
+		return NT_STATUS_USER_SESSION_DELETED;
+	}
+
+	if (table == NULL) {
+		/* this might happen before the end of negprot */
+		return NT_STATUS_USER_SESSION_DELETED;
+	}
+
+	if (table->local.db_ctx == NULL) {
+		return NT_STATUS_INTERNAL_ERROR;
+	}
+
+	key = smbXsrv_session_local_id_to_key(session_wire_id, key_buf);
+
+	status = dbwrap_parse_record(table->local.db_ctx, key,
+				     smbXsrv_session_local_fetch_parser,
+				     &state);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+	if (!NT_STATUS_IS_OK(state.status)) {
+		return state.status;
+	}
+	if (state.session->global->auth_session_info == NULL) {
+		return NT_STATUS_USER_SESSION_DELETED;
+	}
+
+	*session = state.session;
+	return NT_STATUS_OK;
+}
+
 NTSTATUS smb2srv_session_table_init(struct smbXsrv_connection *conn)
 {
 	/*