[U-Boot,16/18] tpm: add dictionary attack mitigation commands support

diff --git a/cmd/tpm.c b/cmd/tpm.c
index 7fcfbf8550..533da2d2ac 100644
--- a/cmd/tpm.c
+++ b/cmd/tpm.c
@@ -480,6 +480,58 @@  static int do_tpm_init(cmd_tbl_t *cmdtp, int flag,
 	return report_return_code(tpm_init());
 }
 
+static int do_tpm_dam_reset_counter(cmd_tbl_t *cmdtp, int flag,
+				    int argc, char *const argv[])
+{
+	const char *pw = (argc < 2) ? NULL : argv[1];
+	const ssize_t pw_sz = pw ? strlen(pw) : 0;
+
+	if (argc > 2)
+		return CMD_RET_USAGE;
+
+	if (pw_sz > TPM2_DIGEST_LENGTH)
+		return -EINVAL;
+
+	return report_return_code(tpm2_dam_reset_counter(pw, pw_sz));
+}
+
+static int do_tpm_dam_set_parameters(cmd_tbl_t *cmdtp, int flag,
+				     int argc, char *const argv[])
+{
+	const char *pw = (argc < 5) ? NULL : argv[4];
+	const ssize_t pw_sz = pw ? strlen(pw) : 0;
+	/*
+	 * No Dictionary Attack Mitigation (DAM) means:
+	 * maxtries = 0xFFFFFFFF, recovery_time = 0, lockout_recovery = 1
+	 */
+	unsigned long int max_tries;
+	unsigned long int recovery_time;
+	unsigned long int lockout_recovery;
+
+	if (argc < 4 || argc > 5)
+		return CMD_RET_USAGE;
+
+	if (pw_sz > TPM2_DIGEST_LENGTH)
+		return -EINVAL;
+
+	if (strict_strtoul(argv[1], 0, &max_tries))
+		return CMD_RET_USAGE;
+
+	if (strict_strtoul(argv[2], 0, &recovery_time))
+		return CMD_RET_USAGE;
+
+	if (strict_strtoul(argv[3], 0, &lockout_recovery))
+		return CMD_RET_USAGE;
+
+	debug("Changing dictionary attack parameters:\n");
+	debug("- maxTries: %lu\n- recoveryTime: %lu\n- lockoutRecovery: %lu\n",
+	      max_tries, recovery_time, lockout_recovery);
+
+	return report_return_code(tpm2_dam_set_parameters(pw, pw_sz, max_tries,
+							 recovery_time,
+							 lockout_recovery));
+}
+
 static int do_tpm_force_clear(cmd_tbl_t *cmdtp, int flag,
 			      int argc, char * const argv[])
 {
@@ -901,6 +953,10 @@  static cmd_tbl_t tpm_commands[] = {
 			 do_tpm_self_test_full, "", ""),
 	U_BOOT_CMD_MKENT(continue_self_test, 0, 1,
 			 do_tpm_continue_self_test, "", ""),
+	U_BOOT_CMD_MKENT(dam_reset_counter, 0, 1,
+			 do_tpm_dam_reset_counter, "", ""),
+	U_BOOT_CMD_MKENT(dam_set_parameters, 0, 1,
+			 do_tpm_dam_set_parameters, "", ""),
 	U_BOOT_CMD_MKENT(force_clear, 0, 1,
 			 do_tpm_force_clear, "", ""),
 	U_BOOT_CMD_MKENT(physical_enable, 0, 1,
@@ -1010,6 +1066,19 @@  U_BOOT_CMD(tpm, CONFIG_SYS_MAXARGS, 1, do_tpm,
 "  get_capability <cap_area|capability> <sub_cap|property> <addr> <count>\n"
 "    - Read <count> bytes of TPM capability indexed by <cap_area|capability>\n"
 "      and <sub_cap|property> to memory address <addr>.\n"
+"Lockout/Dictionary attack Commands:\n"
+"  dam_reset_counter [<password>]\n"
+"    - If the TPM is not in a LOCKOUT state, reset the internal error\n"
+"      counter (TPMv2 only)\n"
+"  dam_set_parameters <maxTries> <recoveryTime> <lockoutRecovery> [<password>]\n"
+"    - If the TPM is not in a LOCKOUT state, set the dictionary attack\n"
+"      parameters:\n"
+"          * maxTries: maximum number of failures before lockout.\n"
+"                          0 means always locking.\n"
+"          * recoveryTime: time before decrementation of the error counter,\n"
+"                          0 means no lockout.\n"
+"          * lockoutRecovery: time of a lockout (before the next try)\n"
+"                          0 means a reboot is needed.\n"
 #if defined(CONFIG_TPM_FLUSH_RESOURCES) || defined(CONFIG_TPM_LIST_RESOURCES)
 "Resource management functions\n"
 #endif
diff --git a/include/tpm.h b/include/tpm.h
index 369119fc1b..4d062584f9 100644
--- a/include/tpm.h
+++ b/include/tpm.h
@@ -60,6 +60,8 @@  enum tpm2_command_codes {
 	TPM2_CC_SELF_TEST	= 0x0143,
 	TPM2_CC_CLEAR		= 0x0126,
 	TPM2_CC_CLEARCONTROL	= 0x0127,
+	TPM2_CC_DAM_RESET	= 0x0139,
+	TPM2_CC_DAM_PARAMETERS	= 0x013A,
 	TPM2_CC_GET_CAPABILITY	= 0x017A,
 	TPM2_CC_PCR_READ	= 0x017E,
 	TPM2_CC_PCR_EXTEND	= 0x0182,
@@ -594,6 +596,30 @@  uint32_t tpm_tsc_physical_presence(uint16_t presence);
  */
 uint32_t tpm_read_pubek(void *data, size_t count);
 
+/**
+ * Issue a TPM2_DictionaryAttackLockReset command.
+ *
+ * @param pw		Password
+ * @param pw_sz		Length of the password
+ * @return return code of the operation
+ */
+int tpm2_dam_reset_counter(const char *pw, const ssize_t pw_sz);
+
+/**
+ * Issue a TPM2_DictionaryAttackLockParameters command.
+ *
+ * @param pw		Password
+ * @param pw_sz		Length of the password
+ * @param max_tries	Count of authorizations before lockout
+ * @param recovery_time Time before decrementation of the failure count
+ * @param lockout_recovery Time to wait after a lockout
+ * @return return code of the operation
+ */
+int tpm2_dam_set_parameters(const char *pw, const ssize_t pw_sz,
+			    unsigned int max_tries,
+			    unsigned int recovery_time,
+			    unsigned int lockout_recovery);
+
 /**
  * Issue a TPM_ForceClear or a TPM2_Clear command.
  *
diff --git a/lib/tpm.c b/lib/tpm.c
index 59f6cd6dba..1e064e6ff1 100644
--- a/lib/tpm.c
+++ b/lib/tpm.c
@@ -703,6 +703,95 @@  uint32_t tpm_read_pubek(void *data, size_t count)
 	return 0;
 }
 
+int tpm2_dam_reset_counter(const char *pw, const ssize_t pw_sz)
+{
+	u8 command_v2[COMMAND_BUFFER_SIZE] = {
+		STRINGIFY16(TPM2_ST_SESSIONS),	/* TAG */
+		STRINGIFY32(27 + pw_sz),	/* Command size */
+		STRINGIFY32(TPM2_CC_DAM_RESET),	/* Command code */
+
+		/* HANDLE */
+		STRINGIFY32(TPM2_RH_LOCKOUT),	/* TPM resource handle */
+
+		/* AUTH_SESSION */
+		STRINGIFY32(9 + pw_sz),		/* Authorization size */
+		STRINGIFY32(TPM2_RS_PW),	/* Session handle */
+		STRINGIFY16(0),			/* Size of <nonce> */
+						/* <nonce> (if any) */
+		0,				/* Attributes: Cont/Excl/Rst */
+		STRINGIFY16(pw_sz),		/* Size of <hmac/password> */
+		/* STRING(pw)			   <hmac/password> (if any) */
+	};
+	unsigned int offset = 27;
+	int ret;
+
+	if (!is_tpmv2)
+		return TPM_LIB_ERROR;
+
+	/*
+	 * Fill the command structure starting from the first buffer:
+	 *     - the password (if any)
+	 */
+	ret = pack_byte_string(command_v2, sizeof(command_v2), "s",
+			       offset, pw, pw_sz);
+	offset += pw_sz;
+	if (ret)
+		return TPM_LIB_ERROR;
+
+	return tpm_sendrecv_command(command_v2, NULL, NULL);
+}
+
+int tpm2_dam_set_parameters(const char *pw, const ssize_t pw_sz,
+			    unsigned int max_tries, unsigned int recovery_time,
+			    unsigned int lockout_recovery)
+{
+	u8 command_v2[COMMAND_BUFFER_SIZE] = {
+		STRINGIFY16(TPM2_ST_SESSIONS),	/* TAG */
+		STRINGIFY32(27 + pw_sz + 12),	/* Command size */
+		STRINGIFY32(TPM2_CC_DAM_PARAMETERS), /* Command code */
+
+		/* HANDLE */
+		STRINGIFY32(TPM2_RH_LOCKOUT),	/* TPM resource handle */
+
+		/* AUTH_SESSION */
+		STRINGIFY32(9 + pw_sz),		/* Authorization size */
+		STRINGIFY32(TPM2_RS_PW),	/* Session handle */
+		STRINGIFY16(0),			/* Size of <nonce> */
+						/* <nonce> (if any) */
+		0,				/* Attributes: Cont/Excl/Rst */
+		STRINGIFY16(pw_sz),		/* Size of <hmac/password> */
+		/* STRING(pw)			   <hmac/password> (if any) */
+
+		/* LOCKOUT PARAMETERS */
+		/* STRIGIFY32(max_tries)	   Max tries (0, always lock) */
+		/* STRIGIFY32(recovery_time)	   Recovery time (0, no lock) */
+		/* STRIGIFY32(lockout_recovery)	   Lockout recovery */
+	};
+	unsigned int offset = 27;
+	int ret;
+
+	if (!is_tpmv2)
+		return TPM_LIB_ERROR;
+
+	/*
+	 * Fill the command structure starting from the first buffer:
+	 *     - the password (if any)
+	 *     - max tries
+	 *     - recovery time
+	 *     - lockout recovery
+	 */
+	ret = pack_byte_string(command_v2, sizeof(command_v2), "sddd",
+			       offset, pw, pw_sz,
+			       offset + pw_sz, max_tries,
+			       offset + pw_sz + 4, recovery_time,
+			       offset + pw_sz + 8, lockout_recovery);
+	offset += pw_sz + 12;
+	if (ret)
+		return TPM_LIB_ERROR;
+
+	return tpm_sendrecv_command(command_v2, NULL, NULL);
+}
+
 int tpm_force_clear(u32 handle, const char *pw, const ssize_t pw_sz)
 {
 	const u8 command_v1[10] = {