diff --git a/libpldm/base.c b/libpldm/base.c
new file mode 100644
index 0000000..db32ca4
--- /dev/null
+++ b/libpldm/base.c
@@ -0,0 +1,104 @@
+#include <endian.h>
+#include <string.h>
+
+#include "base.h"
+
+int encode_get_types_req(uint8_t instance_id, struct pldm_msg *msg)
+{
+	if (msg == NULL) {
+		return PLDM_ERROR_INVALID_DATA;
+	}
+
+	return PLDM_SUCCESS;
+}
+
+int encode_get_commands_req(uint8_t instance_id, uint8_t type,
+			    struct pldm_version version, struct pldm_msg *msg)
+{
+	if (msg == NULL) {
+		return PLDM_ERROR_INVALID_DATA;
+	}
+
+	uint8_t *dst = msg->body.payload;
+	memcpy(dst, &type, sizeof(type));
+	dst += sizeof(type);
+	memcpy(dst, &version, sizeof(version));
+
+	return PLDM_SUCCESS;
+}
+
+int encode_get_types_resp(uint8_t instance_id, uint8_t completion_code,
+			  const uint8_t *types, struct pldm_msg *msg)
+{
+	if (msg == NULL) {
+		return PLDM_ERROR_INVALID_DATA;
+	}
+
+	msg->body.payload[0] = completion_code;
+	if (msg->body.payload[0] == PLDM_SUCCESS) {
+		if (types == NULL) {
+			return PLDM_ERROR_INVALID_DATA;
+		}
+		uint8_t *dst = msg->body.payload + sizeof(msg->body.payload[0]);
+		memcpy(dst, types, PLDM_MAX_TYPES / 8);
+	}
+
+	return PLDM_SUCCESS;
+}
+
+int decode_get_commands_req(const struct pldm_msg_payload *msg, uint8_t *type,
+			    struct pldm_version *version)
+{
+	if (msg == NULL || type == NULL || version == NULL) {
+		return PLDM_ERROR_INVALID_DATA;
+	}
+
+	const uint8_t *start = msg->payload;
+	*type = *start;
+	memcpy(version, (struct pldm_version *)(start + sizeof(*type)),
+	       sizeof(*version));
+
+	return PLDM_SUCCESS;
+}
+
+int encode_get_commands_resp(uint8_t instance_id, uint8_t completion_code,
+			     const uint8_t *commands, struct pldm_msg *msg)
+{
+	if (msg == NULL) {
+		return PLDM_ERROR_INVALID_DATA;
+	}
+
+	msg->body.payload[0] = completion_code;
+	if (msg->body.payload[0] == PLDM_SUCCESS) {
+		if (commands == NULL) {
+			return PLDM_ERROR_INVALID_DATA;
+		}
+		uint8_t *dst = msg->body.payload + sizeof(msg->body.payload[0]);
+		memcpy(dst, commands, PLDM_MAX_CMDS_PER_TYPE / 8);
+	}
+
+	return PLDM_SUCCESS;
+}
+
+int decode_get_types_resp(const struct pldm_msg_payload *msg, uint8_t *types)
+{
+	if (msg == NULL || types == NULL) {
+		return PLDM_ERROR_INVALID_DATA;
+	}
+	const uint8_t *src = msg->payload + sizeof(uint8_t);
+	memcpy(types, src, PLDM_MAX_TYPES / 8);
+
+	return PLDM_SUCCESS;
+}
+
+int decode_get_commands_resp(const struct pldm_msg_payload *msg,
+			     uint8_t *commands)
+{
+	if (msg == NULL || commands == NULL) {
+		return PLDM_ERROR_INVALID_DATA;
+	}
+	const uint8_t *src = msg->payload + sizeof(uint8_t);
+	memcpy(commands, src, PLDM_MAX_CMDS_PER_TYPE / 8);
+
+	return PLDM_SUCCESS;
+}