diff --git a/src/dsp/file.c b/src/dsp/file.c
new file mode 100644
index 0000000..d9c2a21
--- /dev/null
+++ b/src/dsp/file.c
@@ -0,0 +1,79 @@
+/* SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later */
+#include "dsp/base.h"
+#include "msgbuf.h"
+
+#include <libpldm/base.h>
+#include <libpldm/file.h>
+#include <libpldm/utils.h>
+
+#include <assert.h>
+#include <errno.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <string.h>
+#include <stdlib.h>
+
+LIBPLDM_ABI_TESTING
+int encode_pldm_file_df_open_req(uint8_t instance_id,
+				 const struct pldm_file_df_open_req *req,
+				 struct pldm_msg *msg, size_t payload_length)
+{
+	PLDM_MSGBUF_DEFINE_P(buf);
+	int rc;
+
+	if (req == NULL || msg == NULL) {
+		return -EINVAL;
+	}
+
+	struct pldm_header_info header = { 0 };
+	header.instance = instance_id;
+	header.msg_type = PLDM_REQUEST;
+	header.pldm_type = PLDM_FILE;
+	header.command = PLDM_FILE_CMD_DF_OPEN;
+
+	rc = pack_pldm_header_errno(&header, &(msg->hdr));
+	if (rc) {
+		return rc;
+	}
+
+	rc = pldm_msgbuf_init_errno(buf, PLDM_DF_OPEN_REQ_BYTES, msg->payload,
+				    payload_length);
+	if (rc) {
+		return rc;
+	}
+
+	pldm_msgbuf_insert(buf, req->file_identifier);
+	pldm_msgbuf_insert(buf, req->file_attribute.value);
+
+	return pldm_msgbuf_complete(buf);
+}
+
+LIBPLDM_ABI_TESTING
+int decode_pldm_file_df_open_resp(const struct pldm_msg *msg,
+				  size_t payload_length,
+				  struct pldm_file_df_open_resp *resp)
+{
+	PLDM_MSGBUF_DEFINE_P(buf);
+	int rc;
+
+	if (!msg || !resp) {
+		return -EINVAL;
+	}
+
+	rc = pldm_msg_has_error(msg, payload_length);
+	if (rc) {
+		resp->completion_code = rc;
+		return 0;
+	}
+
+	rc = pldm_msgbuf_init_errno(buf, PLDM_DF_OPEN_RESP_BYTES, msg->payload,
+				    payload_length);
+	if (rc) {
+		return rc;
+	}
+
+	pldm_msgbuf_extract(buf, resp->completion_code);
+	pldm_msgbuf_extract(buf, resp->file_descriptor);
+
+	return pldm_msgbuf_complete_consumed(buf);
+}