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authorTimos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>2023-10-10 11:40:56 +0000
committerTimos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>2023-10-10 11:40:56 +0000
commite02cda008591317b1625707ff8e115a4841aa889 (patch)
treeaee302e3cf8b59ec2d32ec481be3d1afddfc8968 /backends/tpm/tpm_util.c
parentcc668e6b7e0ffd8c9d130513d12053cf5eda1d3b (diff)
Introduce Virtio-loopback epsilon release:
Epsilon release introduces a new compatibility layer which make virtio-loopback design to work with QEMU and rust-vmm vhost-user backend without require any changes. Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com> Change-Id: I52e57563e08a7d0bdc002f8e928ee61ba0c53dd9
Diffstat (limited to 'backends/tpm/tpm_util.c')
-rw-r--r--backends/tpm/tpm_util.c369
1 files changed, 369 insertions, 0 deletions
diff --git a/backends/tpm/tpm_util.c b/backends/tpm/tpm_util.c
new file mode 100644
index 000000000..a6e6d3e72
--- /dev/null
+++ b/backends/tpm/tpm_util.c
@@ -0,0 +1,369 @@
+/*
+ * TPM utility functions
+ *
+ * Copyright (c) 2010 - 2015 IBM Corporation
+ * Authors:
+ * Stefan Berger <stefanb@us.ibm.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/error-report.h"
+#include "qapi/error.h"
+#include "qapi/visitor.h"
+#include "tpm_int.h"
+#include "exec/memory.h"
+#include "hw/qdev-properties.h"
+#include "sysemu/tpm_backend.h"
+#include "sysemu/tpm_util.h"
+#include "trace.h"
+
+/* tpm backend property */
+
+static void get_tpm(Object *obj, Visitor *v, const char *name, void *opaque,
+ Error **errp)
+{
+ TPMBackend **be = object_field_prop_ptr(obj, opaque);
+ char *p;
+
+ p = g_strdup(*be ? (*be)->id : "");
+ visit_type_str(v, name, &p, errp);
+ g_free(p);
+}
+
+static void set_tpm(Object *obj, Visitor *v, const char *name, void *opaque,
+ Error **errp)
+{
+ Property *prop = opaque;
+ TPMBackend *s, **be = object_field_prop_ptr(obj, prop);
+ char *str;
+
+ if (!visit_type_str(v, name, &str, errp)) {
+ return;
+ }
+
+ s = qemu_find_tpm_be(str);
+ if (s == NULL) {
+ error_setg(errp, "Property '%s.%s' can't find value '%s'",
+ object_get_typename(obj), name, str);
+ } else if (tpm_backend_init(s, TPM_IF(obj), errp) == 0) {
+ *be = s; /* weak reference, avoid cyclic ref */
+ }
+ g_free(str);
+}
+
+static void release_tpm(Object *obj, const char *name, void *opaque)
+{
+ Property *prop = opaque;
+ TPMBackend **be = object_field_prop_ptr(obj, prop);
+
+ if (*be) {
+ tpm_backend_reset(*be);
+ }
+}
+
+const PropertyInfo qdev_prop_tpm = {
+ .name = "str",
+ .description = "ID of a tpm to use as a backend",
+ .get = get_tpm,
+ .set = set_tpm,
+ .release = release_tpm,
+};
+
+/*
+ * Write an error message in the given output buffer.
+ */
+void tpm_util_write_fatal_error_response(uint8_t *out, uint32_t out_len)
+{
+ if (out_len >= sizeof(struct tpm_resp_hdr)) {
+ tpm_cmd_set_tag(out, TPM_TAG_RSP_COMMAND);
+ tpm_cmd_set_size(out, sizeof(struct tpm_resp_hdr));
+ tpm_cmd_set_error(out, TPM_FAIL);
+ }
+}
+
+bool tpm_util_is_selftest(const uint8_t *in, uint32_t in_len)
+{
+ if (in_len >= sizeof(struct tpm_req_hdr)) {
+ return tpm_cmd_get_ordinal(in) == TPM_ORD_ContinueSelfTest;
+ }
+
+ return false;
+}
+
+/*
+ * Send request to a TPM device. We expect a response within one second.
+ */
+static int tpm_util_request(int fd,
+ const void *request,
+ size_t requestlen,
+ void *response,
+ size_t responselen)
+{
+ fd_set readfds;
+ int n;
+ struct timeval tv = {
+ .tv_sec = 1,
+ .tv_usec = 0,
+ };
+
+ n = write(fd, request, requestlen);
+ if (n < 0) {
+ return -errno;
+ }
+ if (n != requestlen) {
+ return -EFAULT;
+ }
+
+ FD_ZERO(&readfds);
+ FD_SET(fd, &readfds);
+
+ /* wait for a second */
+ n = select(fd + 1, &readfds, NULL, NULL, &tv);
+ if (n != 1) {
+ return -errno;
+ }
+
+ n = read(fd, response, responselen);
+ if (n < sizeof(struct tpm_resp_hdr)) {
+ return -EFAULT;
+ }
+
+ /* check the header */
+ if (tpm_cmd_get_size(response) != n) {
+ return -EMSGSIZE;
+ }
+
+ return 0;
+}
+
+/*
+ * A basic test of a TPM device. We expect a well formatted response header
+ * (error response is fine).
+ */
+static int tpm_util_test(int fd,
+ const void *request,
+ size_t requestlen,
+ uint16_t *return_tag)
+{
+ char buf[1024];
+ ssize_t ret;
+
+ ret = tpm_util_request(fd, request, requestlen,
+ buf, sizeof(buf));
+ if (ret < 0) {
+ return ret;
+ }
+
+ *return_tag = tpm_cmd_get_tag(buf);
+
+ return 0;
+}
+
+/*
+ * Probe for the TPM device in the back
+ * Returns 0 on success with the version of the probed TPM set, 1 on failure.
+ */
+int tpm_util_test_tpmdev(int tpm_fd, TPMVersion *tpm_version)
+{
+ /*
+ * Sending a TPM1.2 command to a TPM2 should return a TPM1.2
+ * header (tag = 0xc4) and error code (TPM_BADTAG = 0x1e)
+ *
+ * Sending a TPM2 command to a TPM 2 will give a TPM 2 tag in the
+ * header.
+ * Sending a TPM2 command to a TPM 1.2 will give a TPM 1.2 tag
+ * in the header and an error code.
+ */
+ const struct tpm_req_hdr test_req = {
+ .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
+ .len = cpu_to_be32(sizeof(test_req)),
+ .ordinal = cpu_to_be32(TPM_ORD_GetTicks),
+ };
+
+ const struct tpm_req_hdr test_req_tpm2 = {
+ .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
+ .len = cpu_to_be32(sizeof(test_req_tpm2)),
+ .ordinal = cpu_to_be32(TPM2_CC_ReadClock),
+ };
+ uint16_t return_tag;
+ int ret;
+
+ /* Send TPM 2 command */
+ ret = tpm_util_test(tpm_fd, &test_req_tpm2,
+ sizeof(test_req_tpm2), &return_tag);
+ /* TPM 2 would respond with a tag of TPM2_ST_NO_SESSIONS */
+ if (!ret && return_tag == TPM2_ST_NO_SESSIONS) {
+ *tpm_version = TPM_VERSION_2_0;
+ return 0;
+ }
+
+ /* Send TPM 1.2 command */
+ ret = tpm_util_test(tpm_fd, &test_req,
+ sizeof(test_req), &return_tag);
+ if (!ret && return_tag == TPM_TAG_RSP_COMMAND) {
+ *tpm_version = TPM_VERSION_1_2;
+ /* this is a TPM 1.2 */
+ return 0;
+ }
+
+ *tpm_version = TPM_VERSION_UNSPEC;
+
+ return 1;
+}
+
+int tpm_util_get_buffer_size(int tpm_fd, TPMVersion tpm_version,
+ size_t *buffersize)
+{
+ int ret;
+
+ switch (tpm_version) {
+ case TPM_VERSION_1_2: {
+ const struct tpm_req_get_buffer_size {
+ struct tpm_req_hdr hdr;
+ uint32_t capability;
+ uint32_t len;
+ uint32_t subcap;
+ } QEMU_PACKED tpm_get_buffer_size = {
+ .hdr = {
+ .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
+ .len = cpu_to_be32(sizeof(tpm_get_buffer_size)),
+ .ordinal = cpu_to_be32(TPM_ORD_GetCapability),
+ },
+ .capability = cpu_to_be32(TPM_CAP_PROPERTY),
+ .len = cpu_to_be32(sizeof(uint32_t)),
+ .subcap = cpu_to_be32(TPM_CAP_PROP_INPUT_BUFFER),
+ };
+ struct tpm_resp_get_buffer_size {
+ struct tpm_resp_hdr hdr;
+ uint32_t len;
+ uint32_t buffersize;
+ } QEMU_PACKED tpm_resp;
+
+ ret = tpm_util_request(tpm_fd, &tpm_get_buffer_size,
+ sizeof(tpm_get_buffer_size),
+ &tpm_resp, sizeof(tpm_resp));
+ if (ret < 0) {
+ return ret;
+ }
+
+ if (be32_to_cpu(tpm_resp.hdr.len) != sizeof(tpm_resp) ||
+ be32_to_cpu(tpm_resp.len) != sizeof(uint32_t)) {
+ trace_tpm_util_get_buffer_size_hdr_len(
+ be32_to_cpu(tpm_resp.hdr.len),
+ sizeof(tpm_resp));
+ trace_tpm_util_get_buffer_size_len(be32_to_cpu(tpm_resp.len),
+ sizeof(uint32_t));
+ error_report("tpm_util: Got unexpected response to "
+ "TPM_GetCapability; errcode: 0x%x",
+ be32_to_cpu(tpm_resp.hdr.errcode));
+ return -EFAULT;
+ }
+ *buffersize = be32_to_cpu(tpm_resp.buffersize);
+ break;
+ }
+ case TPM_VERSION_2_0: {
+ const struct tpm2_req_get_buffer_size {
+ struct tpm_req_hdr hdr;
+ uint32_t capability;
+ uint32_t property;
+ uint32_t count;
+ } QEMU_PACKED tpm2_get_buffer_size = {
+ .hdr = {
+ .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
+ .len = cpu_to_be32(sizeof(tpm2_get_buffer_size)),
+ .ordinal = cpu_to_be32(TPM2_CC_GetCapability),
+ },
+ .capability = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES),
+ .property = cpu_to_be32(TPM2_PT_MAX_COMMAND_SIZE),
+ .count = cpu_to_be32(2), /* also get TPM2_PT_MAX_RESPONSE_SIZE */
+ };
+ struct tpm2_resp_get_buffer_size {
+ struct tpm_resp_hdr hdr;
+ uint8_t more;
+ uint32_t capability;
+ uint32_t count;
+ uint32_t property1;
+ uint32_t value1;
+ uint32_t property2;
+ uint32_t value2;
+ } QEMU_PACKED tpm2_resp;
+
+ ret = tpm_util_request(tpm_fd, &tpm2_get_buffer_size,
+ sizeof(tpm2_get_buffer_size),
+ &tpm2_resp, sizeof(tpm2_resp));
+ if (ret < 0) {
+ return ret;
+ }
+
+ if (be32_to_cpu(tpm2_resp.hdr.len) != sizeof(tpm2_resp) ||
+ be32_to_cpu(tpm2_resp.count) != 2) {
+ trace_tpm_util_get_buffer_size_hdr_len2(
+ be32_to_cpu(tpm2_resp.hdr.len),
+ sizeof(tpm2_resp));
+ trace_tpm_util_get_buffer_size_len2(
+ be32_to_cpu(tpm2_resp.count), 2);
+ error_report("tpm_util: Got unexpected response to "
+ "TPM2_GetCapability; errcode: 0x%x",
+ be32_to_cpu(tpm2_resp.hdr.errcode));
+ return -EFAULT;
+ }
+ *buffersize = MAX(be32_to_cpu(tpm2_resp.value1),
+ be32_to_cpu(tpm2_resp.value2));
+ break;
+ }
+ case TPM_VERSION_UNSPEC:
+ return -EFAULT;
+ }
+
+ trace_tpm_util_get_buffer_size(*buffersize);
+
+ return 0;
+}
+
+void tpm_sized_buffer_reset(TPMSizedBuffer *tsb)
+{
+ g_free(tsb->buffer);
+ tsb->buffer = NULL;
+ tsb->size = 0;
+}
+
+void tpm_util_show_buffer(const unsigned char *buffer,
+ size_t buffer_size, const char *string)
+{
+ size_t len, i;
+ char *line_buffer, *p;
+
+ if (!trace_event_get_state_backends(TRACE_TPM_UTIL_SHOW_BUFFER)) {
+ return;
+ }
+ len = MIN(tpm_cmd_get_size(buffer), buffer_size);
+
+ /*
+ * allocate enough room for 3 chars per buffer entry plus a
+ * newline after every 16 chars and a final null terminator.
+ */
+ line_buffer = g_malloc(len * 3 + (len / 16) + 1);
+
+ for (i = 0, p = line_buffer; i < len; i++) {
+ if (i && !(i % 16)) {
+ p += sprintf(p, "\n");
+ }
+ p += sprintf(p, "%.2X ", buffer[i]);
+ }
+ trace_tpm_util_show_buffer(string, len, line_buffer);
+
+ g_free(line_buffer);
+}