git: 0daf5f02cfaf - main - bhyve/tpm: create crb thread for sending tpm commands
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Date: Tue, 20 Jun 2023 09:01:01 UTC
The branch main has been updated by corvink:
URL: https://cgit.FreeBSD.org/src/commit/?id=0daf5f02cfaf08a7fad75d934bbea50242c98ab3
commit 0daf5f02cfaf08a7fad75d934bbea50242c98ab3
Author: Corvin Köhne <corvink@FreeBSD.org>
AuthorDate: 2022-08-29 10:10:44 +0000
Commit: Corvin Köhne <corvink@FreeBSD.org>
CommitDate: 2023-06-20 08:59:00 +0000
bhyve/tpm: create crb thread for sending tpm commands
Commands send to a tpm are very slow. They can take up to several
seconds for completion. For that reason, create a thread which issues
the commands to the tpm device.
Reviewed by: markj
MFC after: 1 week
Sponsored by: Beckhoff Automation GmbH & Co. KG
Differential Revision: https://reviews.freebsd.org/D40458
---
usr.sbin/bhyve/tpm_device.c | 2 +-
usr.sbin/bhyve/tpm_emul.h | 2 +
usr.sbin/bhyve/tpm_intf.h | 3 +-
usr.sbin/bhyve/tpm_intf_crb.c | 102 +++++++++++++++++++++++++++++++++++++++++-
4 files changed, 105 insertions(+), 4 deletions(-)
diff --git a/usr.sbin/bhyve/tpm_device.c b/usr.sbin/bhyve/tpm_device.c
index 94e9f1ffdc27..3ff480d5e6bb 100644
--- a/usr.sbin/bhyve/tpm_device.c
+++ b/usr.sbin/bhyve/tpm_device.c
@@ -141,7 +141,7 @@ tpm_device_create(struct tpm_device **const new_dev, struct vmctx *const vm_ctx,
}
if (dev->intf->init) {
- error = dev->intf->init(&dev->intf_sc);
+ error = dev->intf->init(&dev->intf_sc, dev->emul, dev->emul_sc);
if (error)
goto err_out;
}
diff --git a/usr.sbin/bhyve/tpm_emul.h b/usr.sbin/bhyve/tpm_emul.h
index f75c0318d37e..24452c92d3b8 100644
--- a/usr.sbin/bhyve/tpm_emul.h
+++ b/usr.sbin/bhyve/tpm_emul.h
@@ -18,5 +18,7 @@ struct tpm_emul {
int (*init)(void **sc, nvlist_t *nvl);
void (*deinit)(void *sc);
+ int (*execute_cmd)(void *sc, void *cmd, uint32_t cmd_size, void *rsp,
+ uint32_t rsp_size);
};
#define TPM_EMUL_SET(x) DATA_SET(tpm_emul_set, x)
diff --git a/usr.sbin/bhyve/tpm_intf.h b/usr.sbin/bhyve/tpm_intf.h
index 3003d8fbd754..020743c0c3f1 100644
--- a/usr.sbin/bhyve/tpm_intf.h
+++ b/usr.sbin/bhyve/tpm_intf.h
@@ -11,6 +11,7 @@
#include "config.h"
#include "tpm_device.h"
+#include "tpm_emul.h"
#define TPM_INTF_TYPE_FIFO_PTP 0x0
#define TPM_INTF_TYPE_CRB 0x1
@@ -30,7 +31,7 @@
struct tpm_intf {
const char *name;
- int (*init)(void **sc);
+ int (*init)(void **sc, struct tpm_emul *emul, void *emul_sc);
void (*deinit)(void *sc);
int (*build_acpi_table)(void *sc, struct vmctx *vm_ctx);
};
diff --git a/usr.sbin/bhyve/tpm_intf_crb.c b/usr.sbin/bhyve/tpm_intf_crb.c
index b8ae33c5ec0a..a920eb5a67e6 100644
--- a/usr.sbin/bhyve/tpm_intf_crb.c
+++ b/usr.sbin/bhyve/tpm_intf_crb.c
@@ -26,6 +26,7 @@
#include "config.h"
#include "mem.h"
#include "qemu_fwcfg.h"
+#include "tpm_device.h"
#include "tpm_intf.h"
#define TPM_CRB_ADDRESS 0xFED40000
@@ -45,6 +46,8 @@
#define TPM_CRB_LOG_AREA_FWCFG_NAME "etc/tpm/log"
+#define TPM_CRB_INTF_NAME "crb"
+
struct tpm_crb_regs {
union tpm_crb_reg_loc_state {
struct {
@@ -164,17 +167,82 @@ static_assert(sizeof(struct tpm_crb_regs) == TPM_CRB_REGS_SIZE,
} while (0)
struct tpm_crb {
+ struct tpm_emul *emul;
+ void *emul_sc;
uint8_t tpm_log_area[TPM_CRB_LOG_AREA_MINIMUM_SIZE];
struct tpm_crb_regs regs;
+ pthread_t thread;
+ pthread_mutex_t mutex;
+ pthread_cond_t cond;
+ bool closing;
};
+static void *
+tpm_crb_thread(void *const arg)
+{
+ struct tpm_crb *const crb = arg;
+
+ pthread_mutex_lock(&crb->mutex);
+ for (;;) {
+ pthread_cond_wait(&crb->cond, &crb->mutex);
+
+ if (crb->closing)
+ break;
+
+ const uint64_t cmd_addr = CRB_CMD_ADDR_READ(crb->regs);
+ const uint64_t rsp_addr = CRB_RSP_ADDR_READ(crb->regs);
+ const uint32_t cmd_size = CRB_CMD_SIZE_READ(crb->regs);
+ const uint32_t rsp_size = CRB_RSP_SIZE_READ(crb->regs);
+
+ const uint64_t cmd_off = cmd_addr - TPM_CRB_DATA_BUFFER_ADDRESS;
+ const uint64_t rsp_off = rsp_addr - TPM_CRB_DATA_BUFFER_ADDRESS;
+
+ if (cmd_off > TPM_CRB_DATA_BUFFER_SIZE ||
+ cmd_off + cmd_size > TPM_CRB_DATA_BUFFER_SIZE ||
+ rsp_off > TPM_CRB_DATA_BUFFER_SIZE ||
+ rsp_off + rsp_size > TPM_CRB_DATA_BUFFER_SIZE) {
+ warnx(
+ "%s: invalid cmd [%16lx, %16lx] --> [%16lx, %16lx]\n\r",
+ __func__, cmd_addr, cmd_addr + cmd_size, rsp_addr,
+ rsp_addr + rsp_size);
+ break;
+ }
+
+ /*
+ * The command response buffer interface uses a single buffer
+ * for sending a command to and receiving a response from the
+ * tpm. To avoid reading old data from the command buffer which
+ * might be a security issue, we zero out the command buffer
+ * before writing the response into it. The rsp_size parameter
+ * is controlled by the guest and it's not guaranteed that the
+ * response has a size of rsp_size (e.g. if the tpm returned an
+ * error, the response would have a different size than
+ * expected). For that reason, use a second buffer for the
+ * response.
+ */
+ uint8_t rsp[TPM_CRB_DATA_BUFFER_SIZE] = { 0 };
+ crb->emul->execute_cmd(crb->emul_sc,
+ &crb->regs.data_buffer[cmd_off], cmd_size, &rsp[rsp_off],
+ rsp_size);
+
+ memset(crb->regs.data_buffer, 0, TPM_CRB_DATA_BUFFER_SIZE);
+ memcpy(&crb->regs.data_buffer[rsp_off], &rsp[rsp_off], rsp_size);
+
+ crb->regs.ctrl_start.start = false;
+ }
+ pthread_mutex_unlock(&crb->mutex);
+
+ return (NULL);
+}
+
static int
-tpm_crb_init(void **sc)
+tpm_crb_init(void **sc, struct tpm_emul *emul, void *emul_sc)
{
struct tpm_crb *crb = NULL;
int error;
assert(sc != NULL);
+ assert(emul != NULL);
crb = calloc(1, sizeof(struct tpm_crb));
if (crb == NULL) {
@@ -185,6 +253,9 @@ tpm_crb_init(void **sc)
memset(crb, 0, sizeof(*crb));
+ crb->emul = emul;
+ crb->emul_sc = emul_sc;
+
crb->regs.loc_state.tpm_req_valid_sts = true;
crb->regs.loc_state.tpm_established = true;
@@ -216,6 +287,26 @@ tpm_crb_init(void **sc)
goto err_out;
}
+ error = pthread_mutex_init(&crb->mutex, NULL);
+ if (error) {
+ warnc(error, "%s: failed to init mutex", __func__);
+ goto err_out;
+ }
+
+ error = pthread_cond_init(&crb->cond, NULL);
+ if (error) {
+ warnc(error, "%s: failed to init cond", __func__);
+ goto err_out;
+ }
+
+ error = pthread_create(&crb->thread, NULL, tpm_crb_thread, crb);
+ if (error) {
+ warnx("%s: failed to create thread\n", __func__);
+ goto err_out;
+ }
+
+ pthread_set_name_np(crb->thread, "tpm_intf_crb");
+
*sc = crb;
return (0);
@@ -237,6 +328,13 @@ tpm_crb_deinit(void *sc)
crb = sc;
+ crb->closing = true;
+ pthread_cond_signal(&crb->cond);
+ pthread_join(crb->thread, NULL);
+
+ pthread_cond_destroy(&crb->cond);
+ pthread_mutex_destroy(&crb->mutex);
+
free(crb);
}
@@ -275,7 +373,7 @@ tpm_crb_build_acpi_table(void *sc __unused, struct vmctx *vm_ctx)
}
static struct tpm_intf tpm_intf_crb = {
- .name = "crb",
+ .name = TPM_CRB_INTF_NAME,
.init = tpm_crb_init,
.deinit = tpm_crb_deinit,
.build_acpi_table = tpm_crb_build_acpi_table,