Merge tag 'dm-pull-1aug21' of https://source.denx.de/u-boot/custodians/u-boot-dm

sandbox TPM-emulator improvements
rST documentation and fixes for moveconfig
handle empty 'ranges' property in dtoc
patman warning for invalid tag
clean-ups to 'fdt add' command

5 files changed, 486 insertions, 157 deletions

diff --git a/drivers/tpm/Makefile b/drivers/tpm/Makefile
index f64d20067f..c65be52670 100644
--- a/drivers/tpm/Makefile
+++ b/drivers/tpm/Makefile
@@ -6,11 +6,11 @@ obj-$(CONFIG_$(SPL_TPL_)TPM) += tpm-uclass.o
 obj-$(CONFIG_TPM_ATMEL_TWI) += tpm_atmel_twi.o
 obj-$(CONFIG_TPM_TIS_INFINEON) += tpm_tis_infineon.o
 obj-$(CONFIG_TPM_TIS_LPC) += tpm_tis_lpc.o
-obj-$(CONFIG_TPM_TIS_SANDBOX) += tpm_tis_sandbox.o
+obj-$(CONFIG_TPM_TIS_SANDBOX) += tpm_tis_sandbox.o sandbox_common.o
 obj-$(CONFIG_TPM_ST33ZP24_I2C) += tpm_tis_st33zp24_i2c.o
 obj-$(CONFIG_TPM_ST33ZP24_SPI) += tpm_tis_st33zp24_spi.o
 
 obj-$(CONFIG_$(SPL_TPL_)TPM2_CR50_I2C) += cr50_i2c.o
-obj-$(CONFIG_TPM2_TIS_SANDBOX) += tpm2_tis_sandbox.o
+obj-$(CONFIG_TPM2_TIS_SANDBOX) += tpm2_tis_sandbox.o sandbox_common.o
 obj-$(CONFIG_TPM2_TIS_SPI) += tpm2_tis_spi.o
 obj-$(CONFIG_TPM2_FTPM_TEE) += tpm2_ftpm_tee.o
diff --git a/drivers/tpm/sandbox_common.c b/drivers/tpm/sandbox_common.c
new file mode 100644
index 0000000000..7e0b2502e3
--- /dev/null
+++ b/drivers/tpm/sandbox_common.c
@@ -0,0 +1,77 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Common features for sandbox TPM1 and TPM2 implementations
+ *
+ * Copyright 2021 Google LLC
+ */
+
+#define LOG_CATEGORY	UCLASS_TPM
+
+#include <common.h>
+#include <tpm-v1.h>
+#include <tpm-v2.h>
+#include <asm/unaligned.h>
+#include "sandbox_common.h"
+
+#define TPM_ERR_CODE_OFS	(2 + 4)		/* after tag and size */
+
+int sb_tpm_index_to_seq(u32 index)
+{
+	index &= ~HR_NV_INDEX;
+	switch (index) {
+	case FIRMWARE_NV_INDEX:
+		return NV_SEQ_FIRMWARE;
+	case KERNEL_NV_INDEX:
+		return NV_SEQ_KERNEL;
+	case BACKUP_NV_INDEX:
+		return NV_SEQ_BACKUP;
+	case FWMP_NV_INDEX:
+		return NV_SEQ_FWMP;
+	case MRC_REC_HASH_NV_INDEX:
+		return NV_SEQ_REC_HASH;
+	case 0:
+		return NV_SEQ_GLOBAL_LOCK;
+	case TPM_NV_INDEX_LOCK:
+		return NV_SEQ_ENABLE_LOCKING;
+	}
+
+	printf("Invalid nv index %#x\n", index);
+	return -1;
+}
+
+void sb_tpm_read_data(const struct nvdata_state nvdata[NV_SEQ_COUNT],
+		      enum sandbox_nv_space seq, u8 *buf, int data_ofs,
+		      int length)
+{
+	const struct nvdata_state *nvd = &nvdata[seq];
+
+	if (!nvd->present)
+		put_unaligned_be32(TPM_BADINDEX, buf + TPM_ERR_CODE_OFS);
+	else if (length > nvd->length)
+		put_unaligned_be32(TPM_BAD_DATASIZE, buf + TPM_ERR_CODE_OFS);
+	else
+		memcpy(buf + data_ofs, &nvd->data, length);
+}
+
+void sb_tpm_write_data(struct nvdata_state nvdata[NV_SEQ_COUNT],
+		       enum sandbox_nv_space seq, const u8 *buf, int data_ofs,
+		       int length)
+{
+	struct nvdata_state *nvd = &nvdata[seq];
+
+	if (length > nvd->length)
+		log_err("Invalid length %x (max %x)\n", length, nvd->length);
+	else
+		memcpy(&nvdata[seq].data, buf + data_ofs, length);
+}
+
+void sb_tpm_define_data(struct nvdata_state nvdata[NV_SEQ_COUNT],
+			enum sandbox_nv_space seq, int length)
+{
+	struct nvdata_state *nvd = &nvdata[seq];
+
+	if (length > NV_DATA_SIZE)
+		log_err("Invalid length %x (max %x)\n", length, NV_DATA_SIZE);
+	nvd->length = length;
+	nvd->present = true;
+}
diff --git a/drivers/tpm/sandbox_common.h b/drivers/tpm/sandbox_common.h
new file mode 100644
index 0000000000..e822a200fd
--- /dev/null
+++ b/drivers/tpm/sandbox_common.h
@@ -0,0 +1,108 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Common features for sandbox TPM1 and TPM2 implementations
+ *
+ * Copyright 2021 Google LLC
+ */
+
+#ifndef __TPM_SANDBOX_COMMON_H
+#define __TPM_SANDBOX_COMMON_H
+
+/*
+ * These numbers derive from adding the sizes of command fields as shown in
+ * the TPM commands manual.
+ */
+#define TPM_HDR_LEN	10
+
+/* These are the different non-volatile spaces that we emulate */
+enum sandbox_nv_space {
+	NV_SEQ_ENABLE_LOCKING,
+	NV_SEQ_GLOBAL_LOCK,
+	NV_SEQ_FIRMWARE,
+	NV_SEQ_KERNEL,
+	NV_SEQ_BACKUP,
+	NV_SEQ_FWMP,
+	NV_SEQ_REC_HASH,
+
+	NV_SEQ_COUNT,
+};
+
+/* TPM NVRAM location indices */
+#define FIRMWARE_NV_INDEX		0x1007
+#define KERNEL_NV_INDEX			0x1008
+#define BACKUP_NV_INDEX			0x1009
+#define FWMP_NV_INDEX			0x100a
+#define MRC_REC_HASH_NV_INDEX		0x100b
+
+/* Size of each non-volatile space */
+#define NV_DATA_SIZE		0x28
+
+/**
+ * struct nvdata_state - state of a single non-volatile-data 'space'
+ *
+ * @present: true if present
+ * @length: length in bytes (max NV_DATA_SIZE)
+ * @data: contents of non-volatile space
+ */
+struct nvdata_state {
+	bool present;
+	int length;
+	u8 data[NV_DATA_SIZE];
+};
+
+/**
+ * sb_tpm_index_to_seq() - convert an index into a space sequence number
+ *
+ * This converts the index as used by the vboot code into an internal sequence
+ * number used by the sandbox emulation.
+ *
+ * @index: Index to use (FIRMWARE_NV_INDEX, etc.)
+ * @return associated space (enum sandbox_nv_space)
+ */
+int sb_tpm_index_to_seq(uint index);
+
+/**
+ * sb_tpm_read_data() - Read non-volatile data
+ *
+ * This handles a TPM read of nvdata. If the nvdata is not present, a
+ * TPM_BADINDEX error is put in the buffer. If @length is too large,
+ * TPM_BAD_DATASIZE is put in the buffer.
+ *
+ * @nvdata: Current nvdata state
+ * @seq: Sequence number to read
+ * @recvbuf: Buffer to update with the TPM response, assumed to contain zeroes
+ * @data_ofs: Offset of the 'data' portion of @recvbuf
+ * @length: Number of bytes to read
+ */
+void sb_tpm_read_data(const struct nvdata_state nvdata[NV_SEQ_COUNT],
+		      enum sandbox_nv_space seq, u8 *recvbuf, int data_ofs,
+		      int length);
+
+/**
+ * sb_tpm_write_data() - Write non-volatile data
+ *
+ * If @length is too large, an error is logged and nothing is written.
+ *
+ * @nvdata: Current nvdata state
+ * @seq: Sequence number to read
+ * @buf: Buffer containing the data to write
+ * @data_ofs: Offset of the 'data' portion of @buf
+ * @length: Number of bytes to write
+ */
+void sb_tpm_write_data(struct nvdata_state nvdata[NV_SEQ_COUNT],
+		       enum sandbox_nv_space seq, const u8 *buf, int data_ofs,
+		       int length);
+
+/**
+ * sb_tpm_define_data() - Set up non-volatile data
+ *
+ * If @length is too large, an error is logged and nothing is written.
+ *
+ * @nvdata: Current nvdata state
+ * @seq: Sequence number to set up
+ * @length: Length of space in bytes
+ */
+void sb_tpm_define_data(struct nvdata_state nvdata[NV_SEQ_COUNT],
+			enum sandbox_nv_space seq, int length);
+
+#endif
diff --git a/drivers/tpm/tpm2_tis_sandbox.c b/drivers/tpm/tpm2_tis_sandbox.c
index 24c804a564..ac6eb14353 100644
--- a/drivers/tpm/tpm2_tis_sandbox.c
+++ b/drivers/tpm/tpm2_tis_sandbox.c
@@ -11,6 +11,8 @@
 #include <asm/unaligned.h>
 #include <linux/bitops.h>
 #include <u-boot/crc.h>
+#include <u-boot/sha256.h>
+#include "sandbox_common.h"
 
 /* Hierarchies */
 enum tpm2_hierarchy {
@@ -38,29 +40,178 @@ enum tpm2_cap_tpm_property {
 
 #define SANDBOX_TPM_PCR_NB 1
 
-static const u8 sandbox_extended_once_pcr[] = {
-	0xf5, 0xa5, 0xfd, 0x42, 0xd1, 0x6a, 0x20, 0x30,
-	0x27, 0x98, 0xef, 0x6e, 0xd3, 0x09, 0x97, 0x9b,
-	0x43, 0x00, 0x3d, 0x23, 0x20, 0xd9, 0xf0, 0xe8,
-	0xea, 0x98, 0x31, 0xa9, 0x27, 0x59, 0xfb, 0x4b,
-};
-
+/*
+ * Information about our TPM emulation. This is preserved in the sandbox
+ * state file if enabled.
+ *
+ * @valid: true if this is valid (only used in s_state)
+ * @init_done: true if open() has been called
+ * @startup_done: true if TPM2_CC_STARTUP has been processed
+ * @tests_done: true if TPM2_CC_SELF_TEST has be processed
+ * @pw: TPM password per hierarchy
+ * @pw_sz: Size of each password in bytes
+ * @properties: TPM properties
+ * @pcr: TPM Platform Configuration Registers. Each of these holds a hash and
+ *	can be 'extended' a number of times, meaning another hash is added into
+ *	its value (initial value all zeroes)
+ * @pcr_extensions: Number of times each PCR has been extended (starts at 0)
+ * @nvdata: non-volatile data, used to store important things for the platform
+ */
 struct sandbox_tpm2 {
+	bool valid;
 	/* TPM internal states */
 	bool init_done;
 	bool startup_done;
 	bool tests_done;
-	/* TPM password per hierarchy */
 	char pw[TPM2_HIERARCHY_NB][TPM2_DIGEST_LEN + 1];
 	int pw_sz[TPM2_HIERARCHY_NB];
-	/* TPM properties */
 	u32 properties[TPM2_PROPERTY_NB];
-	/* TPM PCRs */
 	u8 pcr[SANDBOX_TPM_PCR_NB][TPM2_DIGEST_LEN];
-	/* TPM PCR extensions */
 	u32 pcr_extensions[SANDBOX_TPM_PCR_NB];
+	struct nvdata_state nvdata[NV_SEQ_COUNT];
 };
 
+static struct sandbox_tpm2 s_state, *g_state;
+
+/**
+ * sandbox_tpm2_read_state() - read the sandbox EC state from the state file
+ *
+ * If data is available, then blob and node will provide access to it. If
+ * not this function sets up an empty TPM.
+ *
+ * @blob: Pointer to device tree blob, or NULL if no data to read
+ * @node: Node offset to read from
+ */
+static int sandbox_tpm2_read_state(const void *blob, int node)
+{
+	struct sandbox_tpm2 *state = &s_state;
+	char prop_name[20];
+	const char *prop;
+	int len;
+	int i;
+
+	if (!blob)
+		return 0;
+	state->tests_done = fdtdec_get_int(blob, node, "tests-done", 0);
+
+	for (i = 0; i < TPM2_HIERARCHY_NB; i++) {
+		snprintf(prop_name, sizeof(prop_name), "pw%d", i);
+
+		prop = fdt_getprop(blob, node, prop_name, &len);
+		if (len > TPM2_DIGEST_LEN)
+			return log_msg_ret("pw", -E2BIG);
+		if (prop) {
+			memcpy(state->pw[i], prop, len);
+			state->pw_sz[i] = len;
+		}
+	}
+
+	for (i = 0; i < TPM2_PROPERTY_NB; i++) {
+		snprintf(prop_name, sizeof(prop_name), "properties%d", i);
+		state->properties[i] = fdtdec_get_uint(blob, node, prop_name,
+						       0);
+	}
+
+	for (i = 0; i < SANDBOX_TPM_PCR_NB; i++) {
+		int subnode;
+
+		snprintf(prop_name, sizeof(prop_name), "pcr%d", i);
+		subnode = fdt_subnode_offset(blob, node, prop_name);
+		if (subnode < 0)
+			continue;
+		prop = fdt_getprop(blob, subnode, "value", &len);
+		if (len != TPM2_DIGEST_LEN)
+			return log_msg_ret("pcr", -E2BIG);
+		memcpy(state->pcr[i], prop, TPM2_DIGEST_LEN);
+		state->pcr_extensions[i] = fdtdec_get_uint(blob, subnode,
+							   "extensions", 0);
+	}
+
+	for (i = 0; i < NV_SEQ_COUNT; i++) {
+		struct nvdata_state *nvd = &state->nvdata[i];
+
+		sprintf(prop_name, "nvdata%d", i);
+		prop = fdt_getprop(blob, node, prop_name, &len);
+		if (len > NV_DATA_SIZE)
+			return log_msg_ret("nvd", -E2BIG);
+		if (prop) {
+			memcpy(nvd->data, prop, len);
+			nvd->length = len;
+			nvd->present = true;
+		}
+	}
+	s_state.valid = true;
+
+	return 0;
+}
+
+/**
+ * sandbox_tpm2_write_state() - Write out our state to the state file
+ *
+ * The caller will ensure that there is a node ready for the state. The node
+ * may already contain the old state, in which case it is overridden.
+ *
+ * @blob: Device tree blob holding state
+ * @node: Node to write our state into
+ */
+static int sandbox_tpm2_write_state(void *blob, int node)
+{
+	const struct sandbox_tpm2 *state = g_state;
+	char prop_name[20];
+	int i;
+
+	if (!state)
+		return 0;
+
+	/*
+	 * We are guaranteed enough space to write basic properties. This is
+	 * SANDBOX_STATE_MIN_SPACE.
+	 *
+	 * We could use fdt_add_subnode() to put each set of data in its
+	 * own node - perhaps useful if we add access information to each.
+	 */
+	fdt_setprop_u32(blob, node, "tests-done", state->tests_done);
+
+	for (i = 0; i < TPM2_HIERARCHY_NB; i++) {
+		if (state->pw_sz[i]) {
+			snprintf(prop_name, sizeof(prop_name), "pw%d", i);
+			fdt_setprop(blob, node, prop_name, state->pw[i],
+				    state->pw_sz[i]);
+		}
+	}
+
+	for (i = 0; i < TPM2_PROPERTY_NB; i++) {
+		snprintf(prop_name, sizeof(prop_name), "properties%d", i);
+		fdt_setprop_u32(blob, node, prop_name, state->properties[i]);
+	}
+
+	for (i = 0; i < SANDBOX_TPM_PCR_NB; i++) {
+		int subnode;
+
+		snprintf(prop_name, sizeof(prop_name), "pcr%d", i);
+		subnode = fdt_add_subnode(blob, node, prop_name);
+		fdt_setprop(blob, subnode, "value", state->pcr[i],
+			    TPM2_DIGEST_LEN);
+		fdt_setprop_u32(blob, subnode, "extensions",
+				state->pcr_extensions[i]);
+	}
+
+	for (i = 0; i < NV_SEQ_COUNT; i++) {
+		const struct nvdata_state *nvd = &state->nvdata[i];
+
+		if (nvd->present) {
+			snprintf(prop_name, sizeof(prop_name), "nvdata%d", i);
+			fdt_setprop(blob, node, prop_name, nvd->data,
+				    nvd->length);
+		}
+	}
+
+	return 0;
+}
+
+SANDBOX_STATE_IO(sandbox_tpm2, "sandbox,tpm2", sandbox_tpm2_read_state,
+		 sandbox_tpm2_write_state);
+
 /*
  * Check the tag validity depending on the command (authentication required or
  * not). If authentication is required, check it is valid. Update the auth
@@ -93,6 +244,10 @@ static int sandbox_tpm2_check_session(struct udevice *dev, u32 command, u16 tag,
 	case TPM2_CC_DAM_RESET:
 	case TPM2_CC_DAM_PARAMETERS:
 	case TPM2_CC_PCR_EXTEND:
+	case TPM2_CC_NV_READ:
+	case TPM2_CC_NV_WRITE:
+	case TPM2_CC_NV_WRITELOCK:
+	case TPM2_CC_NV_DEFINE_SPACE:
 		if (tag != TPM2_ST_SESSIONS) {
 			printf("Session required for command 0x%x\n", command);
 			return TPM2_RC_AUTH_CONTEXT;
@@ -121,6 +276,10 @@ static int sandbox_tpm2_check_session(struct udevice *dev, u32 command, u16 tag,
 			break;
 		case TPM2_RH_PLATFORM:
 			*hierarchy = TPM2_HIERARCHY_PLATFORM;
+			if (command == TPM2_CC_NV_READ ||
+			    command == TPM2_CC_NV_WRITE ||
+			    command == TPM2_CC_NV_WRITELOCK)
+				*auth += sizeof(u32);
 			break;
 		default:
 			printf("Wrong handle 0x%x\n", handle);
@@ -242,15 +401,17 @@ static int sandbox_tpm2_extend(struct udevice *dev, int pcr_index,
 			       const u8 *extension)
 {
 	struct sandbox_tpm2 *tpm = dev_get_priv(dev);
-	int i;
+	sha256_context ctx;
 
-	/* Only simulate the first extensions from all '0' with only '0' */
-	for (i = 0; i < TPM2_DIGEST_LEN; i++)
-		if (tpm->pcr[pcr_index][i] || extension[i])
-			return TPM2_RC_FAILURE;
+	/* Zero the PCR if this is the first use */
+	if (!tpm->pcr_extensions[pcr_index])
+		memset(tpm->pcr[pcr_index], '\0', TPM2_DIGEST_LEN);
+
+	sha256_starts(&ctx);
+	sha256_update(&ctx, tpm->pcr[pcr_index], TPM2_DIGEST_LEN);
+	sha256_update(&ctx, extension, TPM2_DIGEST_LEN);
+	sha256_finish(&ctx, tpm->pcr[pcr_index]);
 
-	memcpy(tpm->pcr[pcr_index], sandbox_extended_once_pcr,
-	       TPM2_DIGEST_LEN);
 	tpm->pcr_extensions[pcr_index]++;
 
 	return 0;
@@ -477,15 +638,8 @@ static int sandbox_tpm2_xfer(struct udevice *dev, const u8 *sendbuf,
 		for (i = 0; i < pcr_array_sz; i++)
 			pcr_map += (u64)sent[i] << (i * 8);
 
-		if (pcr_map >> SANDBOX_TPM_PCR_NB) {
-			printf("Sandbox TPM handles up to %d PCR(s)\n",
-			       SANDBOX_TPM_PCR_NB);
-			rc = TPM2_RC_VALUE;
-			return sandbox_tpm2_fill_buf(recv, recv_len, tag, rc);
-		}
-
 		if (!pcr_map) {
-			printf("Empty PCR map.\n");
+			printf("Empty PCR map\n");
 			rc = TPM2_RC_VALUE;
 			return sandbox_tpm2_fill_buf(recv, recv_len, tag, rc);
 		}
@@ -494,6 +648,13 @@ static int sandbox_tpm2_xfer(struct udevice *dev, const u8 *sendbuf,
 			if (pcr_map & BIT(i))
 				pcr_index = i;
 
+		if (pcr_index >= SANDBOX_TPM_PCR_NB) {
+			printf("Invalid index %d, sandbox TPM handles up to %d PCR(s)\n",
+			       pcr_index, SANDBOX_TPM_PCR_NB);
+			rc = TPM2_RC_VALUE;
+			return sandbox_tpm2_fill_buf(recv, recv_len, tag, rc);
+		}
+
 		/* Write tag */
 		put_unaligned_be16(tag, recv);
 		recv += sizeof(tag);
@@ -527,9 +688,9 @@ static int sandbox_tpm2_xfer(struct udevice *dev, const u8 *sendbuf,
 		pcr_index = get_unaligned_be32(sendbuf + sizeof(tag) +
 					       sizeof(length) +
 					       sizeof(command));
-		if (pcr_index > SANDBOX_TPM_PCR_NB) {
-			printf("Sandbox TPM handles up to %d PCR(s)\n",
-			       SANDBOX_TPM_PCR_NB);
+		if (pcr_index >= SANDBOX_TPM_PCR_NB) {
+			printf("Invalid index %d, sandbox TPM handles up to %d PCR(s)\n",
+			       pcr_index, SANDBOX_TPM_PCR_NB);
 			rc = TPM2_RC_VALUE;
 		}
 
@@ -557,6 +718,64 @@ static int sandbox_tpm2_xfer(struct udevice *dev, const u8 *sendbuf,
 		sandbox_tpm2_fill_buf(recv, recv_len, tag, rc);
 		break;
 
+	case TPM2_CC_NV_READ: {
+		int index, seq;
+
+		index = get_unaligned_be32(sendbuf + TPM2_HDR_LEN + 4);
+		length = get_unaligned_be16(sent);
+		/* ignore offset */
+		seq = sb_tpm_index_to_seq(index);
+		if (seq < 0)
+			return log_msg_ret("index", -EINVAL);
+		printf("tpm: nvread index=%#02x, len=%#02x, seq=%#02x\n", index,
+		       length, seq);
+		*recv_len = TPM2_HDR_LEN + 6 + length;
+		memset(recvbuf, '\0', *recv_len);
+		put_unaligned_be32(length, recvbuf + 2);
+		sb_tpm_read_data(tpm->nvdata, seq, recvbuf,
+				 TPM2_HDR_LEN + 4 + 2, length);
+		break;
+	}
+	case TPM2_CC_NV_WRITE: {
+		int index, seq;
+
+		index = get_unaligned_be32(sendbuf + TPM2_HDR_LEN + 4);
+		length = get_unaligned_be16(sent);
+		sent += sizeof(u16);
+
+		/* ignore offset */
+		seq = sb_tpm_index_to_seq(index);
+		if (seq < 0)
+			return log_msg_ret("index", -EINVAL);
+		printf("tpm: nvwrite index=%#02x, len=%#02x, seq=%#02x\n", index,
+		       length, seq);
+		memcpy(&tpm->nvdata[seq].data, sent, length);
+		tpm->nvdata[seq].present = true;
+		*recv_len = TPM2_HDR_LEN + 2;
+		memset(recvbuf, '\0', *recv_len);
+		break;
+	}
+	case TPM2_CC_NV_DEFINE_SPACE: {
+		int policy_size, index, seq;
+
+		policy_size = get_unaligned_be16(sent + 12);
+		index = get_unaligned_be32(sent + 2);
+		sent += 14 + policy_size;
+		length = get_unaligned_be16(sent);
+		seq = sb_tpm_index_to_seq(index);
+		if (seq < 0)
+			return -EINVAL;
+		printf("tpm: define_space index=%x, len=%x, seq=%x, policy_size=%x\n",
+		       index, length, seq, policy_size);
+		sb_tpm_define_data(tpm->nvdata, seq, length);
+		*recv_len = 12;
+		memset(recvbuf, '\0', *recv_len);
+		break;
+	}
+	case TPM2_CC_NV_WRITELOCK:
+		*recv_len = 12;
+		memset(recvbuf, '\0', *recv_len);
+		break;
 	default:
 		printf("TPM2 command %02x unknown in Sandbox\n", command);
 		rc = TPM2_RC_COMMAND_CODE;
@@ -594,11 +813,13 @@ static int sandbox_tpm2_probe(struct udevice *dev)
 	/* Use the TPM v2 stack */
 	priv->version = TPM_V2;
 
-	memset(tpm, 0, sizeof(*tpm));
-
 	priv->pcr_count = 32;
 	priv->pcr_select_min = 2;
 
+	if (s_state.valid)
+		memcpy(tpm, &s_state, sizeof(*tpm));
+	g_state = tpm;
+
 	return 0;
 }
 
diff --git a/drivers/tpm/tpm_tis_sandbox.c b/drivers/tpm/tpm_tis_sandbox.c
index 67139cea3b..efbeb00ab6 100644
--- a/drivers/tpm/tpm_tis_sandbox.c
+++ b/drivers/tpm/tpm_tis_sandbox.c
@@ -9,61 +9,10 @@
 #include <asm/state.h>
 #include <asm/unaligned.h>
 #include <u-boot/crc.h>
-
-/* TPM NVRAM location indices. */
-#define FIRMWARE_NV_INDEX		0x1007
-#define KERNEL_NV_INDEX			0x1008
-#define BACKUP_NV_INDEX                 0x1009
-#define FWMP_NV_INDEX                   0x100a
-#define REC_HASH_NV_INDEX               0x100b
-#define REC_HASH_NV_SIZE                VB2_SHA256_DIGEST_SIZE
+#include "sandbox_common.h"
 
 #define NV_DATA_PUBLIC_PERMISSIONS_OFFSET	60
 
-/* Kernel TPM space - KERNEL_NV_INDEX, locked with physical presence */
-#define ROLLBACK_SPACE_KERNEL_VERSION	2
-#define ROLLBACK_SPACE_KERNEL_UID	0x4752574C  /* 'GRWL' */
-
-struct rollback_space_kernel {
-	/* Struct version, for backwards compatibility */
-	uint8_t struct_version;
-	/* Unique ID to detect space redefinition */
-	uint32_t uid;
-	/* Kernel versions */
-	uint32_t kernel_versions;
-	/* Reserved for future expansion */
-	uint8_t reserved[3];
-	/* Checksum (v2 and later only) */
-	uint8_t crc8;
-} __packed rollback_space_kernel;
-
-/*
- * These numbers derive from adding the sizes of command fields as shown in
- * the TPM commands manual.
- */
-#define TPM_REQUEST_HEADER_LENGTH	10
-#define TPM_RESPONSE_HEADER_LENGTH	10
-
-/* These are the different non-volatile spaces that we emulate */
-enum {
-	NV_GLOBAL_LOCK,
-	NV_SEQ_FIRMWARE,
-	NV_SEQ_KERNEL,
-	NV_SEQ_BACKUP,
-	NV_SEQ_FWMP,
-	NV_SEQ_REC_HASH,
-
-	NV_SEQ_COUNT,
-};
-
-/* Size of each non-volatile space */
-#define NV_DATA_SIZE		0x20
-
-struct nvdata_state {
-	bool present;
-	u8 data[NV_DATA_SIZE];
-};
-
 /*
  * Information about our TPM emulation. This is preserved in the sandbox
  * state file if enabled.
@@ -71,7 +20,7 @@ struct nvdata_state {
 static struct tpm_state {
 	bool valid;
 	struct nvdata_state nvdata[NV_SEQ_COUNT];
-} g_state;
+} s_state, *g_state;
 
 /**
  * sandbox_tpm_read_state() - read the sandbox EC state from the state file
@@ -84,6 +33,7 @@ static struct tpm_state {
  */
 static int sandbox_tpm_read_state(const void *blob, int node)
 {
+	struct tpm_state *state = &s_state;
 	const char *prop;
 	int len;
 	int i;
@@ -92,22 +42,27 @@ static int sandbox_tpm_read_state(const void *blob, int node)
 		return 0;
 
 	for (i = 0; i < NV_SEQ_COUNT; i++) {
+		struct nvdata_state *nvd = &state->nvdata[i];
 		char prop_name[20];
 
 		sprintf(prop_name, "nvdata%d", i);
 		prop = fdt_getprop(blob, node, prop_name, &len);
-		if (prop && len == NV_DATA_SIZE) {
-			memcpy(g_state.nvdata[i].data, prop, NV_DATA_SIZE);
-			g_state.nvdata[i].present = true;
+		if (len >= NV_DATA_SIZE)
+			return log_msg_ret("nvd", -E2BIG);
+		if (prop) {
+			memcpy(nvd->data, prop, len);
+			nvd->length = len;
+			nvd->present = true;
 		}
 	}
-	g_state.valid = true;
+
+	s_state.valid = true;
 
 	return 0;
 }
 
 /**
- * cros_ec_write_state() - Write out our state to the state file
+ * sandbox_tpm_write_state() - Write out our state to the state file
  *
  * The caller will ensure that there is a node ready for the state. The node
  * may already contain the old state, in which case it is overridden.
@@ -117,20 +72,25 @@ static int sandbox_tpm_read_state(const void *blob, int node)
  */
 static int sandbox_tpm_write_state(void *blob, int node)
 {
+	const struct tpm_state *state = g_state;
 	int i;
 
+	if (!state)
+		return 0;
+
 	/*
 	 * We are guaranteed enough space to write basic properties.
 	 * We could use fdt_add_subnode() to put each set of data in its
 	 * own node - perhaps useful if we add access informaiton to each.
 	 */
 	for (i = 0; i < NV_SEQ_COUNT; i++) {
+		const struct nvdata_state *nvd = &state->nvdata[i];
 		char prop_name[20];
 
-		if (g_state.nvdata[i].present) {
-			sprintf(prop_name, "nvdata%d", i);
-			fdt_setprop(blob, node, prop_name,
-				    g_state.nvdata[i].data, NV_DATA_SIZE);
+		if (nvd->present) {
+			snprintf(prop_name, sizeof(prop_name), "nvdata%d", i);
+			fdt_setprop(blob, node, prop_name, nvd->data,
+				    nvd->length);
 		}
 	}
 
@@ -140,27 +100,6 @@ static int sandbox_tpm_write_state(void *blob, int node)
 SANDBOX_STATE_IO(sandbox_tpm, "google,sandbox-tpm", sandbox_tpm_read_state,
 		 sandbox_tpm_write_state);
 
-static int index_to_seq(uint32_t index)
-{
-	switch (index) {
-	case FIRMWARE_NV_INDEX:
-		return NV_SEQ_FIRMWARE;
-	case KERNEL_NV_INDEX:
-		return NV_SEQ_KERNEL;
-	case BACKUP_NV_INDEX:
-		return NV_SEQ_BACKUP;
-	case FWMP_NV_INDEX:
-		return NV_SEQ_FWMP;
-	case REC_HASH_NV_INDEX:
-		return NV_SEQ_REC_HASH;
-	case 0:
-		return NV_GLOBAL_LOCK;
-	}
-
-	printf("Invalid nv index %#x\n", index);
-	return -1;
-}
-
 static void handle_cap_flag_space(u8 **datap, uint index)
 {
 	struct tpm_nv_data_public pub;
@@ -201,16 +140,13 @@ static int sandbox_tpm_xfer(struct udevice *dev, const uint8_t *sendbuf,
 			printf("Get flags index %#02x\n", index);
 			*recv_len = 22;
 			memset(recvbuf, '\0', *recv_len);
-			data = recvbuf + TPM_RESPONSE_HEADER_LENGTH +
-					sizeof(uint32_t);
+			data = recvbuf + TPM_HDR_LEN + sizeof(uint32_t);
 			switch (index) {
 			case FIRMWARE_NV_INDEX:
 				break;
 			case KERNEL_NV_INDEX:
 				handle_cap_flag_space(&data, index);
-				*recv_len = data - recvbuf -
-					TPM_RESPONSE_HEADER_LENGTH -
-					sizeof(uint32_t);
+				*recv_len = data - recvbuf;
 				break;
 			case TPM_CAP_FLAG_PERMANENT: {
 				struct tpm_permanent_flags *pflags;
@@ -227,15 +163,12 @@ static int sandbox_tpm_xfer(struct udevice *dev, const uint8_t *sendbuf,
 				printf("   ** Unknown flags index %x\n", index);
 				return -ENOSYS;
 			}
-			put_unaligned_be32(*recv_len,
-					   recvbuf +
-					   TPM_RESPONSE_HEADER_LENGTH);
+			put_unaligned_be32(*recv_len, recvbuf + TPM_HDR_LEN);
 			break;
 		case TPM_CAP_NV_INDEX:
 			index = get_unaligned_be32(sendbuf + 18);
 			printf("Get cap nv index %#02x\n", index);
-			put_unaligned_be32(22, recvbuf +
-					   TPM_RESPONSE_HEADER_LENGTH);
+			put_unaligned_be32(22, recvbuf + TPM_HDR_LEN);
 			break;
 		default:
 			printf("   ** Unknown 0x65 command type %#02x\n",
@@ -246,54 +179,42 @@ static int sandbox_tpm_xfer(struct udevice *dev, const uint8_t *sendbuf,
 	case TPM_CMD_NV_WRITE_VALUE:
 		index = get_unaligned_be32(sendbuf + 10);
 		length = get_unaligned_be32(sendbuf + 18);
-		seq = index_to_seq(index);
+		seq = sb_tpm_index_to_seq(index);
 		if (seq < 0)
 			return -EINVAL;
 		printf("tpm: nvwrite index=%#02x, len=%#02x\n", index, length);
-		memcpy(&tpm->nvdata[seq].data, sendbuf + 22, length);
-		tpm->nvdata[seq].present = true;
-		*recv_len = 12;
-		memset(recvbuf, '\0', *recv_len);
+		sb_tpm_write_data(tpm->nvdata, seq, sendbuf, 22, length);
 		break;
 	case TPM_CMD_NV_READ_VALUE: /* nvread */
 		index = get_unaligned_be32(sendbuf + 10);
 		length = get_unaligned_be32(sendbuf + 18);
-		seq = index_to_seq(index);
+		seq = sb_tpm_index_to_seq(index);
 		if (seq < 0)
 			return -EINVAL;
 		printf("tpm: nvread index=%#02x, len=%#02x, seq=%#02x\n", index,
 		       length, seq);
-		*recv_len = TPM_RESPONSE_HEADER_LENGTH + sizeof(uint32_t) +
-					length;
+		*recv_len = TPM_HDR_LEN + sizeof(uint32_t) + length;
 		memset(recvbuf, '\0', *recv_len);
-		put_unaligned_be32(length, recvbuf +
-				   TPM_RESPONSE_HEADER_LENGTH);
-		if (seq == NV_SEQ_KERNEL) {
-			struct rollback_space_kernel rsk;
-
-			data = recvbuf + TPM_RESPONSE_HEADER_LENGTH +
-					sizeof(uint32_t);
-			memset(&rsk, 0, sizeof(struct rollback_space_kernel));
-			rsk.struct_version = 2;
-			rsk.uid = ROLLBACK_SPACE_KERNEL_UID;
-			rsk.crc8 = crc8(0, (unsigned char *)&rsk,
-					offsetof(struct rollback_space_kernel,
-						 crc8));
-			memcpy(data, &rsk, sizeof(rsk));
-		} else if (!tpm->nvdata[seq].present) {
-			put_unaligned_be32(TPM_BADINDEX, recvbuf +
-					   sizeof(uint16_t) + sizeof(uint32_t));
-		} else {
-			memcpy(recvbuf + TPM_RESPONSE_HEADER_LENGTH +
-			       sizeof(uint32_t), &tpm->nvdata[seq].data,
-			       length);
-		}
+		put_unaligned_be32(length, recvbuf + TPM_HDR_LEN);
+		sb_tpm_read_data(tpm->nvdata, seq, recvbuf, TPM_HDR_LEN + 4,
+				 length);
 		break;
 	case TPM_CMD_EXTEND:
 		*recv_len = 30;
 		memset(recvbuf, '\0', *recv_len);
 		break;
 	case TPM_CMD_NV_DEFINE_SPACE:
+		index = get_unaligned_be32(sendbuf + 12);
+		length = get_unaligned_be32(sendbuf + 77);
+		seq = sb_tpm_index_to_seq(index);
+		if (seq < 0)
+			return -EINVAL;
+		printf("tpm: define_space index=%#02x, len=%#02x, seq=%#02x\n",
+		       index, length, seq);
+		sb_tpm_define_data(tpm->nvdata, seq, length);
+		*recv_len = 12;
+		memset(recvbuf, '\0', *recv_len);
+		break;
 	case 0x15: /* pcr read */
 	case 0x5d: /* force clear */
 	case 0x6f: /* physical enable */
@@ -328,7 +249,9 @@ static int sandbox_tpm_probe(struct udevice *dev)
 {
 	struct tpm_state *tpm = dev_get_priv(dev);
 
-	memcpy(tpm, &g_state, sizeof(*tpm));
+	if (s_state.valid)
+		memcpy(tpm, &s_state, sizeof(*tpm));
+	g_state = tpm;
 
 	return 0;
 }