diff --git a/include/sysemu/spdm-socket.h b/include/sysemu/spdm-socket.h
new file mode 100644
index 0000000000..5d8bd9aa4e
--- /dev/null
+++ b/include/sysemu/spdm-socket.h
@@ -0,0 +1,74 @@
+/*
+ * QEMU SPDM socket support
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef SPDM_REQUESTER_H
+#define SPDM_REQUESTER_H
+
+/**
+ * spdm_socket_connect: connect to an external SPDM socket
+ * @port: port to connect to
+ * @errp: error object handle
+ *
+ * This will connect to an external SPDM socket server. On error
+ * it will return -1 and errp will be set. On success this function
+ * will return the socket number.
+ */
+int spdm_socket_connect(uint16_t port, Error **errp);
+
+/**
+ * spdm_socket_rsp: send and receive a message to a SPDM server
+ * @socket: socket returned from spdm_socket_connect()
+ * @transport_type: SPDM_SOCKET_TRANSPORT_TYPE_* macro
+ * @req: request buffer
+ * @req_len: request buffer length
+ * @rsp: response buffer
+ * @rsp_len: response buffer length
+ *
+ * Send platform data to a SPDM server on socket and then receive
+ * a response.
+ */
+uint32_t spdm_socket_rsp(const int socket, uint32_t transport_type,
+                         void *req, uint32_t req_len,
+                         void *rsp, uint32_t rsp_len);
+
+/**
+ * spdm_socket_close: send a shutdown command to the server
+ * @socket: socket returned from spdm_socket_connect()
+ * @transport_type: SPDM_SOCKET_TRANSPORT_TYPE_* macro
+ *
+ * This will issue a shutdown command to the server.
+ */
+void spdm_socket_close(const int socket, uint32_t transport_type);
+
+#define SPDM_SOCKET_COMMAND_NORMAL                0x0001
+#define SPDM_SOCKET_COMMAND_OOB_ENCAP_KEY_UPDATE  0x8001
+#define SPDM_SOCKET_COMMAND_CONTINUE              0xFFFD
+#define SPDM_SOCKET_COMMAND_SHUTDOWN              0xFFFE
+#define SPDM_SOCKET_COMMAND_UNKOWN                0xFFFF
+#define SPDM_SOCKET_COMMAND_TEST                  0xDEAD
+
+#define SPDM_SOCKET_TRANSPORT_TYPE_MCTP           0x01
+#define SPDM_SOCKET_TRANSPORT_TYPE_PCI_DOE        0x02
+
+#define SPDM_SOCKET_MAX_MESSAGE_BUFFER_SIZE       0x1200
+
+#endif
diff --git a/backends/spdm-socket.c b/backends/spdm-socket.c
new file mode 100644
index 0000000000..d0663d696c
--- /dev/null
+++ b/backends/spdm-socket.c
@@ -0,0 +1,216 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+/*
+ * QEMU SPDM socket support
+ *
+ * This is based on:
+ * https://github.com/DMTF/spdm-emu/blob/07c0a838bcc1c6207c656ac75885c0603e344b6f/spdm_emu/spdm_emu_common/command.c
+ * but has been re-written to match QEMU style
+ *
+ * Copyright (c) 2021, DMTF. All rights reserved.
+ * Copyright (c) 2023. Western Digital Corporation or its affiliates.
+ */
+
+#include "qemu/osdep.h"
+#include "sysemu/spdm-socket.h"
+#include "qapi/error.h"
+
+static bool read_bytes(const int socket, uint8_t *buffer,
+                       size_t number_of_bytes)
+{
+    ssize_t number_received = 0;
+    ssize_t result;
+
+    while (number_received < number_of_bytes) {
+        result = recv(socket, buffer + number_received,
+                      number_of_bytes - number_received, 0);
+        if (result <= 0) {
+            return false;
+        }
+        number_received += result;
+    }
+    return true;
+}
+
+static bool read_data32(const int socket, uint32_t *data)
+{
+    bool result;
+
+    result = read_bytes(socket, (uint8_t *)data, sizeof(uint32_t));
+    if (!result) {
+        return result;
+    }
+    *data = ntohl(*data);
+    return true;
+}
+
+static bool read_multiple_bytes(const int socket, uint8_t *buffer,
+                                uint32_t *bytes_received,
+                                uint32_t max_buffer_length)
+{
+    uint32_t length;
+    bool result;
+
+    result = read_data32(socket, &length);
+    if (!result) {
+        return result;
+    }
+
+    if (length > max_buffer_length) {
+        return false;
+    }
+
+    if (bytes_received) {
+        *bytes_received = length;
+    }
+
+    if (length == 0) {
+        return true;
+    }
+
+    return read_bytes(socket, buffer, length);
+}
+
+static bool receive_platform_data(const int socket,
+                                  uint32_t transport_type,
+                                  uint32_t *command,
+                                  uint8_t *receive_buffer,
+                                  uint32_t *bytes_to_receive)
+{
+    bool result;
+    uint32_t response;
+    uint32_t bytes_received;
+
+    result = read_data32(socket, &response);
+    if (!result) {
+        return result;
+    }
+    *command = response;
+
+    result = read_data32(socket, &transport_type);
+    if (!result) {
+        return result;
+    }
+
+    bytes_received = 0;
+    result = read_multiple_bytes(socket, receive_buffer, &bytes_received,
+                                 *bytes_to_receive);
+    if (!result) {
+        return result;
+    }
+    *bytes_to_receive = bytes_received;
+
+    return result;
+}
+
+static bool write_bytes(const int socket, const uint8_t *buffer,
+                        uint32_t number_of_bytes)
+{
+    ssize_t number_sent = 0;
+    ssize_t result;
+
+    while (number_sent < number_of_bytes) {
+        result = send(socket, buffer + number_sent,
+                      number_of_bytes - number_sent, 0);
+        if (result == -1) {
+            return false;
+        }
+        number_sent += result;
+    }
+    return true;
+}
+
+static bool write_data32(const int socket, uint32_t data)
+{
+    data = htonl(data);
+    return write_bytes(socket, (uint8_t *)&data, sizeof(uint32_t));
+}
+
+static bool write_multiple_bytes(const int socket, const uint8_t *buffer,
+                                 uint32_t bytes_to_send)
+{
+    bool result;
+
+    result = write_data32(socket, bytes_to_send);
+    if (!result) {
+        return result;
+    }
+
+    return write_bytes(socket, buffer, bytes_to_send);
+}
+
+static bool send_platform_data(const int socket,
+                               uint32_t transport_type, uint32_t command,
+                               const uint8_t *send_buffer, size_t bytes_to_send)
+{
+    bool result;
+
+    result = write_data32(socket, command);
+    if (!result) {
+        return result;
+    }
+
+    result = write_data32(socket, transport_type);
+    if (!result) {
+        return result;
+    }
+
+    return write_multiple_bytes(socket, send_buffer, bytes_to_send);
+}
+
+int spdm_socket_connect(uint16_t port, Error **errp)
+{
+    int client_socket;
+    struct sockaddr_in server_addr;
+
+    client_socket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
+    if (client_socket < 0) {
+        error_setg(errp, "cannot create socket: %s", strerror(errno));
+        return -1;
+    }
+
+    memset((char *)&server_addr, 0, sizeof(server_addr));
+    server_addr.sin_family = AF_INET;
+    server_addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+    server_addr.sin_port = htons(port);
+
+
+    if (connect(client_socket, (struct sockaddr *)&server_addr,
+                sizeof(server_addr)) < 0) {
+        error_setg(errp, "cannot connect: %s", strerror(errno));
+        close(client_socket);
+        return -1;
+    }
+
+    return client_socket;
+}
+
+uint32_t spdm_socket_rsp(const int socket, uint32_t transport_type,
+                         void *req, uint32_t req_len,
+                         void *rsp, uint32_t rsp_len)
+{
+    uint32_t command;
+    bool result;
+
+    result = send_platform_data(socket, transport_type,
+                                SPDM_SOCKET_COMMAND_NORMAL,
+                                req, req_len);
+    if (!result) {
+        return 0;
+    }
+
+    result = receive_platform_data(socket, transport_type, &command,
+                                   (uint8_t *)rsp, &rsp_len);
+    if (!result) {
+        return 0;
+    }
+
+    assert(command != 0);
+
+    return rsp_len;
+}
+
+void spdm_socket_close(const int socket, uint32_t transport_type)
+{
+    send_platform_data(socket, transport_type,
+                       SPDM_SOCKET_COMMAND_SHUTDOWN, NULL, 0);
+}
diff --git a/MAINTAINERS b/MAINTAINERS
index 93546cfb14..d76b49a597 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3401,6 +3401,12 @@ F: tests/qtest/*tpm*
 F: docs/specs/tpm.rst
 T: git https://github.com/stefanberger/qemu-tpm.git tpm-next
 
+SPDM
+M: Alistair Francis <alistair.francis@wdc.com>
+S: Maintained
+F: backends/spdm-socket.c
+F: include/sysemu/spdm-socket.h
+
 Checkpatch
 S: Odd Fixes
 F: scripts/checkpatch.pl
diff --git a/backends/Kconfig b/backends/Kconfig
index 2cb23f62fa..d3dbe19868 100644
--- a/backends/Kconfig
+++ b/backends/Kconfig
@@ -3,3 +3,7 @@ source tpm/Kconfig
 config IOMMUFD
     bool
     depends on VFIO
+
+config SPDM_SOCKET
+    bool
+    default y
diff --git a/backends/meson.build b/backends/meson.build
index 749b491f12..da714b93d1 100644
--- a/backends/meson.build
+++ b/backends/meson.build
@@ -33,4 +33,6 @@ endif
 system_ss.add(when: gio, if_true: files('dbus-vmstate.c'))
 system_ss.add(when: 'CONFIG_SGX', if_true: files('hostmem-epc.c'))
 
+system_ss.add(when: 'CONFIG_SPDM_SOCKET', if_true: files('spdm-socket.c'))
+
 subdir('tpm')
