From patchwork Tue May 28 03:51:21 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jarkko Sakkinen X-Patchwork-Id: 13676076 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8140D481A3; Tue, 28 May 2024 03:52:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716868344; cv=none; b=l59n6fYe8CzYmye3AavbTAiCe0Kzw8kohU/g1/SliTTSW1NHKc122PgfJtPHufsQJLZcSH1DBvzSYzpXN/Khn2wW/cg6QqNWQmPMkLdEX92fFWeeCFksGQSUzmdM4lNYu8o/ZDNYkPsqwBBIqfDWVFPv4cRiWRv9AoeK8+tT/D8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716868344; c=relaxed/simple; bh=v9MeUiUS8Q/VuRxCC2YKx8zhemgKA48t6o1IF1bDbl0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bOSsW6s4t/p/i0JsRQKJrJAY5JIKOC7JtwsXPfUy4RtRxiEZfbtCbEopDEGUNdT3hI5HETXZArp8CmEaBQxfb9Kkdg/MFbZTUEk2LWHK/L+yJxttHFbU/H8w5pjld6Icrgaq529uQmnJiOyM+IarxYsCrRy/4rCkKN0ndWfOvVU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=kB20Hgfq; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="kB20Hgfq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A42D4C3277B; Tue, 28 May 2024 03:52:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1716868344; bh=v9MeUiUS8Q/VuRxCC2YKx8zhemgKA48t6o1IF1bDbl0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kB20HgfqIdxr8FnPHpdOq7kp5ptxOQks+jQLKLVV4HQuLseViQGgK+5uI0XP2l1DC uPkWS1AEzhNcQ6cCbeRMICjk1Jtxv6W5jhsoZSC9FZv2UILW0KscsyJ9avpVovWhJN 4Hiki8Qb8jyo8B+bY8FsdNfSKe3xMDejnpWyRhJ30wS4M49bpfTms5Kh3ZrvFT0iss LQgMQZH9jxA255/p+svA8VxjMndHlk6Usf0r48dRJYkRFyuwoJf+6LvNjD9bYjNQ2w pr4Arjdd4dz4roiVu+311c/eaogmfMkx+7h6o+N1N9tBr1IZDF1WCHPo7RCT553aF1 yxfyQ1pAhRljQ== From: Jarkko Sakkinen To: Herbert Xu Cc: linux-integrity@vger.kernel.org, keyrings@vger.kernel.org, Andreas.Fuchs@infineon.com, James Prestwood , David Woodhouse , Eric Biggers , James Bottomley , linux-crypto@vger.kernel.org, Stefan Berger , Jarkko Sakkinen , "David S. Miller" , linux-kernel@vger.kernel.org (open list), David Howells , James Bottomley , Ard Biesheuvel , Mario Limonciello Subject: [PATCH v6 6/6] keys: asymmetric: Add tpm2_key_ecdsa Date: Tue, 28 May 2024 06:51:21 +0300 Message-ID: <20240528035136.11464-7-jarkko@kernel.org> X-Mailer: git-send-email 2.45.1 In-Reply-To: <20240528035136.11464-1-jarkko@kernel.org> References: <20240528035136.11464-1-jarkko@kernel.org> Precedence: bulk X-Mailing-List: keyrings@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 * Asymmetric TPM2 ECDSA key with signing and verification. * Enabled with CONFIG_ASYMMETRIC_TPM2_KEY_ECDSA_SUBTYPE. Cc: Stefan Berger Signed-off-by: Jarkko Sakkinen --- v6: * Very first version. * Stefan: any idea why the signature give -EKEYREJECTED? --- crypto/asymmetric_keys/Kconfig | 15 + crypto/asymmetric_keys/Makefile | 1 + crypto/asymmetric_keys/tpm2_key_ecdsa.c | 441 ++++++++++++++++++++++++ crypto/ecdsa.c | 1 - include/linux/tpm.h | 6 + 5 files changed, 463 insertions(+), 1 deletion(-) create mode 100644 crypto/asymmetric_keys/tpm2_key_ecdsa.c diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig index 9d88c1190621..c97f11e0340c 100644 --- a/crypto/asymmetric_keys/Kconfig +++ b/crypto/asymmetric_keys/Kconfig @@ -24,6 +24,21 @@ config ASYMMETRIC_PUBLIC_KEY_SUBTYPE appropriate hash algorithms (such as SHA-1) must be available. ENOPKG will be reported if the requisite algorithm is unavailable. +config ASYMMETRIC_TPM2_KEY_ECDSA_SUBTYPE + tristate "Asymmetric TPM2 ECDSA crypto algorithm subtype" + depends on TCG_TPM + select CRYPTO_ECDSA + select CRYPTO_SHA256 + select CRYPTO_HASH_INFO + select CRYPTO_TPM2_KEY + select ASN1 + select ASN1_ENCODER + help + This option provides support for asymmetric TPM2 key type handling. + If signature generation and/or verification are to be used, + appropriate hash algorithms (such as SHA-256) must be available. + ENOPKG will be reported if the requisite algorithm is unavailable. + config ASYMMETRIC_TPM2_KEY_RSA_SUBTYPE tristate "Asymmetric TPM2 RSA crypto algorithm subtype" depends on TCG_TPM diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile index c6da84607824..0843d2268a69 100644 --- a/crypto/asymmetric_keys/Makefile +++ b/crypto/asymmetric_keys/Makefile @@ -11,6 +11,7 @@ asymmetric_keys-y := \ signature.o obj-$(CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE) += public_key.o +obj-$(CONFIG_ASYMMETRIC_TPM2_KEY_ECDSA_SUBTYPE) += tpm2_key_ecdsa.o obj-$(CONFIG_ASYMMETRIC_TPM2_KEY_RSA_SUBTYPE) += tpm2_key_rsa.o # diff --git a/crypto/asymmetric_keys/tpm2_key_ecdsa.c b/crypto/asymmetric_keys/tpm2_key_ecdsa.c new file mode 100644 index 000000000000..ad99984440fd --- /dev/null +++ b/crypto/asymmetric_keys/tpm2_key_ecdsa.c @@ -0,0 +1,441 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Asymmetric TPM2 ECDSA key subtype. + * + * See Documentation/crypto/asymmetric-keys.rst + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#undef pr_fmt +#define pr_fmt(fmt) "tpm2_key_ecdsa: "fmt + +struct tpm2_ecc_parms { + __be16 symmetric; + __be16 scheme; + __be16 ecc; + __be16 kdf; +}; + +static const u8 *tpm2_key_ecdsa_ecc_x(const struct tpm2_key *key) +{ + const off_t o = key->priv_len + 2 + sizeof(*key->desc); + + return &key->data[o + sizeof(struct tpm2_ecc_parms)]; +} + +static const u8 *tpm2_key_ecdsa_ecc_y(const struct tpm2_key *key) +{ + const u8 *x = tpm2_key_ecdsa_ecc_x(key); + u16 x_size = get_unaligned_be16(&x[0]); + + /* +2 from the size field: */ + return &x[2 + x_size]; +} + +static void tpm2_key_ecdsa_describe(const struct key *asymmetric_key, + struct seq_file *m) +{ + struct tpm2_key *key = asymmetric_key->payload.data[asym_crypto]; + + if (!key) { + pr_err("key missing"); + return; + } + + seq_puts(m, "TPM2/ECDSA"); +} + +static void tpm2_key_ecdsa_destroy(void *payload0, void *payload3) +{ + struct tpm2_key *key = payload0; + + if (!key) + return; + + kfree(key); +} + +static const char *tpm2_ecc_name(u16 ecc) +{ + const char *name; + + switch (ecc) { + case TPM2_ECC_NIST_P521: + name = "ecdsa-nist-p521"; + break; + case TPM2_ECC_NIST_P384: + name = "ecdsa-nist-p384"; + break; + default: + name = "ecdsa-nist-p256"; + break; + } + + return name; +} + +static int tpm2_key_ecdsa_query(const struct kernel_pkey_params *params, + struct kernel_pkey_query *info) +{ + const struct tpm2_key *key = params->key->payload.data[asym_crypto]; + const off_t o = key->priv_len + 2 + sizeof(*key->desc); + const struct tpm2_ecc_parms *p = + (const struct tpm2_ecc_parms *)&key->data[o]; + u16 ecc = be16_to_cpu(p->ecc); + const char *ecc_name = tpm2_ecc_name(ecc); + const u8 *x = tpm2_key_ecdsa_ecc_x(key); + u16 x_size = get_unaligned_be16(&x[0]); + struct crypto_akcipher *tfm; + char data[256]; + u8 *ptr; + int ret; + + memset(data, 0, sizeof(data)); + + tfm = crypto_alloc_akcipher(ecc_name, 0, 0); + if (IS_ERR(tfm)) + return PTR_ERR(tfm); + + /* Probe for ecdsa_set_pub_key(): */ + ptr = &data[0]; + *ptr++ = 0x04; /* uncompressed */ + memcpy(&ptr[0], &x[2], x_size); + memcpy(&ptr[x_size], &x[2 + x_size + 2], x_size); + ret = crypto_akcipher_set_pub_key(tfm, data, 2 * x_size + 1); + crypto_free_akcipher(tfm); + if (ret < 0) + return ret; + + info->max_sig_size = 256; + info->key_size = 256; + info->max_data_size = 256; + info->supported_ops = KEYCTL_SUPPORTS_SIGN | KEYCTL_SUPPORTS_VERIFY; + return ret; +} + +static int tpm2_key_ecdsa_sign(struct tpm_chip *chip, struct tpm2_key *key, + struct kernel_pkey_params *params, + const void *in, void *out) +{ + off_t offset = sizeof(struct tpm_header) + 4; + u16 hash_algo = TPM_ALG_SHA256; + u8 digest[SHA256_DIGEST_SIZE]; + u32 in_len = params->in_len; + struct tpm_buf buf; + u16 digest_size; + u32 key_handle; + u8 *ptr = out; + u16 sig_algo; + int ret; + + /* Require explicit hash algorithm: */ + if (!params->hash_algo) + return -EINVAL; + + /* Currently only support SHA256: */ + if (!!strcmp(params->hash_algo, "sha256")) + return -EINVAL; + + ret = tpm_try_get_ops(chip); + if (ret) + return ret; + + ret = tpm2_start_auth_session(chip); + if (ret) + goto err_ops; + + ret = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD); + if (ret < 0) { + tpm2_end_auth_session(chip); + goto err_ops; + } + + tpm_buf_append_name(chip, &buf, key->parent, NULL); + tpm_buf_append_hmac_session(chip, &buf, TPM2_SA_CONTINUE_SESSION | + TPM2_SA_ENCRYPT, NULL, 0); + tpm_buf_append(&buf, &key->data[0], key->priv_len + key->pub_len); + if (buf.flags & TPM_BUF_OVERFLOW) { + tpm2_end_auth_session(chip); + ret = -E2BIG; + goto err_buf; + } + tpm_buf_fill_hmac_session(chip, &buf); + ret = tpm_transmit_cmd(chip, &buf, 4, "ECDSA loading"); + ret = tpm_buf_check_hmac_response(chip, &buf, ret); + if (ret) { + tpm2_end_auth_session(chip); + ret = -EIO; + goto err_buf; + } + + key_handle = be32_to_cpup((__be32 *)&buf.data[TPM_HEADER_SIZE]); + + tpm_buf_reset(&buf, TPM2_ST_SESSIONS, TPM2_CC_SIGN); + tpm_buf_append_name(chip, &buf, key_handle, NULL); + tpm_buf_append_hmac_session(chip, &buf, TPM2_SA_DECRYPT, NULL, 0); + + sha256(in, in_len, digest); + tpm_buf_append_u16(&buf, SHA256_DIGEST_SIZE); + tpm_buf_append(&buf, digest, SHA256_DIGEST_SIZE); + tpm_buf_append_u16(&buf, TPM_ALG_ECDSA); + tpm_buf_append_u16(&buf, TPM_ALG_SHA256); + + /* 10.7.2 A NULL Ticket */ + tpm_buf_append_u16(&buf, TPM2_ST_HASHCHECK); + tpm_buf_append_u32(&buf, TPM2_RH_NULL); + tpm_buf_append_u16(&buf, 0); + + tpm_buf_fill_hmac_session(chip, &buf); + ret = tpm_transmit_cmd(chip, &buf, 4, "ECDSA signing"); + ret = tpm_buf_check_hmac_response(chip, &buf, ret); + if (ret) { + tpm2_end_auth_session(chip); + ret = -EIO; + goto err_blob; + } + + ret = -EIO; + sig_algo = tpm_buf_read_u16(&buf, &offset); + if (sig_algo != TPM_ALG_ECDSA) + goto err_blob; + + hash_algo = tpm_buf_read_u16(&buf, &offset); + if (hash_algo != TPM_ALG_SHA256) + goto err_blob; + + digest_size = tpm_buf_read_u16(&buf, &offset); + if (digest_size != SHA256_DIGEST_SIZE) + goto err_blob; + + /* SEQUENCE */ + *ptr++ = 0x30; + *ptr++ = 2 * (2 + SHA256_DIGEST_SIZE); + /* INTEGER */ + *ptr++ = 0x02; + *ptr++ = SHA256_DIGEST_SIZE; + memcpy(ptr, &buf.data[offset], SHA256_DIGEST_SIZE); + offset += SHA256_DIGEST_SIZE; + ptr += SHA256_DIGEST_SIZE; + + digest_size = tpm_buf_read_u16(&buf, &offset); + if (digest_size != SHA256_DIGEST_SIZE) + goto err_blob; + + /* INTEGER */ + *ptr++ = 0x02; + *ptr++ = SHA256_DIGEST_SIZE; + memcpy(ptr, &buf.data[offset], SHA256_DIGEST_SIZE); + offset += SHA256_DIGEST_SIZE; + ptr += SHA256_DIGEST_SIZE; + + ret = (void *)ptr - out; + pr_info("ret=%d\n", ret); + +err_blob: + tpm2_flush_context(chip, key_handle); + +err_buf: + tpm_buf_destroy(&buf); + +err_ops: + tpm_put_ops(chip); + return ret; +} + +static int tpm2_key_ecdsa_eds_op(struct kernel_pkey_params *params, + const void *in, void *out) +{ + struct tpm2_key *key = params->key->payload.data[asym_crypto]; + struct tpm_chip *chip = tpm_default_chip(); + + if (!chip) + return -ENODEV; + + switch (params->op) { + case kernel_pkey_sign: + return tpm2_key_ecdsa_sign(chip, key, params, in, out); + default: + return -EOPNOTSUPP; + } +} + +static int tpm2_key_ecdsa_verify_signature(const struct key *key, + const struct public_key_signature *sig) +{ + const struct tpm2_key *tpm2_key = key->payload.data[asym_crypto]; + const off_t o = tpm2_key->priv_len + 2 + sizeof(*tpm2_key->desc); + const struct tpm2_ecc_parms *p = + (const struct tpm2_ecc_parms *)&tpm2_key->data[o]; + u16 ecc = be16_to_cpu(p->ecc); + const char *ecc_name = tpm2_ecc_name(ecc); + const u8 *x = tpm2_key_ecdsa_ecc_x(tpm2_key); + u16 x_size = get_unaligned_be16(&x[0]); + struct akcipher_request *req; + struct scatterlist src_sg[2]; + struct crypto_akcipher *tfm; + struct crypto_wait cwait; + char data[256]; + u8 *ptr; + int ret; + + memset(data, 0, sizeof(data)); + + tfm = crypto_alloc_akcipher(ecc_name, 0, 0); + if (IS_ERR(tfm)) + return PTR_ERR(tfm); + + /* Probe for ecdsa_set_pub_key(): */ + ptr = &data[0]; + *ptr++ = 0x04; /* uncompressed */ + memcpy(&ptr[0], &x[2], x_size); + memcpy(&ptr[x_size], &x[2 + x_size + 2], x_size); + ret = crypto_akcipher_set_pub_key(tfm, data, 2 * x_size + 1); + if (ret) + goto err_tfm; + + ret = -ENOMEM; + req = akcipher_request_alloc(tfm, GFP_KERNEL); + if (!req) + goto err_tfm; + + sg_init_table(src_sg, 2); + sg_set_buf(&src_sg[0], sig->s, sig->s_size); + sg_set_buf(&src_sg[1], sig->digest, sig->digest_size); + akcipher_request_set_crypt(req, src_sg, NULL, sig->s_size, + sig->digest_size); + crypto_init_wait(&cwait); + akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG | + CRYPTO_TFM_REQ_MAY_SLEEP, + crypto_req_done, &cwait); + ret = crypto_wait_req(crypto_akcipher_verify(req), &cwait); + akcipher_request_free(req); + +err_tfm: + crypto_free_akcipher(tfm); + return ret; +} + +/* + * Asymmetric TPM2 ECDSA key. Signs and decrypts with TPM. + */ +struct asymmetric_key_subtype tpm2_key_ecdsa_subtype = { + .owner = THIS_MODULE, + .name = "tpm2_key_ecdsa", + .name_len = sizeof("tpm2_key_ecdsa") - 1, + .describe = tpm2_key_ecdsa_describe, + .destroy = tpm2_key_ecdsa_destroy, + .query = tpm2_key_ecdsa_query, + .eds_op = tpm2_key_ecdsa_eds_op, + .verify_signature = tpm2_key_ecdsa_verify_signature, +}; +EXPORT_SYMBOL_GPL(tpm2_key_ecdsa_subtype); + +static int __tpm2_key_ecdsa_preparse(struct tpm2_key *key) +{ + const off_t o = key->priv_len + 2 + sizeof(*key->desc); + const struct tpm2_ecc_parms *p = + (const struct tpm2_ecc_parms *)&key->data[o]; + u16 x_size, y_size; + const u8 *x, *y; + + if (tpm2_key_type(key) != TPM_ALG_ECC) + return -EBADMSG; + + if (tpm2_key_policy_size(key) != 0) + return -EBADMSG; + + if (be16_to_cpu(p->symmetric) != TPM_ALG_NULL) + return -EBADMSG; + + if (be16_to_cpu(p->scheme) != TPM_ALG_NULL) + return -EBADMSG; + + if (be16_to_cpu(p->ecc) != TPM2_ECC_NIST_P256 && + be16_to_cpu(p->ecc) != TPM2_ECC_NIST_P384 && + be16_to_cpu(p->ecc) != TPM2_ECC_NIST_P521) + return -EBADMSG; + + if (be16_to_cpu(p->kdf) != TPM_ALG_NULL) + return -EBADMSG; + + x = tpm2_key_ecdsa_ecc_x(key); + x_size = get_unaligned_be16(&x[0]); + if (x_size > ECC_MAX_BYTES) + return -EBADMSG; + + y = tpm2_key_ecdsa_ecc_y(key); + y_size = get_unaligned_be16(&y[0]); + if (y_size > ECC_MAX_BYTES) + return -EBADMSG; + + if (x_size != y_size) + return -EBADMSG; + + return 0; +} + +/* + * Attempt to parse a data blob for a key as a TPM private key blob. + */ +static int tpm2_key_ecdsa_preparse(struct key_preparsed_payload *prep) +{ + struct tpm2_key *key; + int ret; + + key = tpm2_key_decode(prep->data, prep->datalen); + if (IS_ERR(key)) + return ret; + + if (key->oid != OID_TPMLoadableKey) { + kfree(key); + return -EBADMSG; + } + + ret = __tpm2_key_ecdsa_preparse(key); + if (ret < 0) { + kfree(key); + return ret; + } + + prep->payload.data[asym_subtype] = &tpm2_key_ecdsa_subtype; + prep->payload.data[asym_key_ids] = NULL; + prep->payload.data[asym_crypto] = key; + prep->payload.data[asym_auth] = NULL; + prep->quotalen = 100; + return 0; +} + +static struct asymmetric_key_parser tpm2_key_ecdsa_parser = { + .owner = THIS_MODULE, + .name = "tpm2_key_ecdsa_parser", + .parse = tpm2_key_ecdsa_preparse, +}; + +static int __init tpm2_key_ecdsa_init(void) +{ + return register_asymmetric_key_parser(&tpm2_key_ecdsa_parser); +} + +static void __exit tpm2_key_ecdsa_exit(void) +{ + unregister_asymmetric_key_parser(&tpm2_key_ecdsa_parser); +} + +module_init(tpm2_key_ecdsa_init); +module_exit(tpm2_key_ecdsa_exit); + +MODULE_DESCRIPTION("Asymmetric TPM2 ECDSA key"); +MODULE_LICENSE("GPL"); diff --git a/crypto/ecdsa.c b/crypto/ecdsa.c index 258fffbf623d..cf7d630c6593 100644 --- a/crypto/ecdsa.c +++ b/crypto/ecdsa.c @@ -236,7 +236,6 @@ static int ecdsa_set_pub_key(struct crypto_akcipher *tfm, const void *key, unsig if (d[0] != 4) return -EINVAL; - keylen--; digitlen = keylen >> 1; ndigits = DIV_ROUND_UP(digitlen, sizeof(u64)); diff --git a/include/linux/tpm.h b/include/linux/tpm.h index a4be7a852bde..b70ba5962102 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -45,6 +45,7 @@ enum tpm_algorithms { TPM_ALG_ERROR = 0x0000, TPM_ALG_RSA = 0x0001, TPM_ALG_SHA1 = 0x0004, + TPM_ALG_HMAC = 0x0004, TPM_ALG_AES = 0x0006, TPM_ALG_KEYEDHASH = 0x0008, TPM_ALG_SHA256 = 0x000B, @@ -52,6 +53,7 @@ enum tpm_algorithms { TPM_ALG_SHA512 = 0x000D, TPM_ALG_NULL = 0x0010, TPM_ALG_SM3_256 = 0x0012, + TPM_ALG_ECDSA = 0x0018, TPM_ALG_ECC = 0x0023, TPM_ALG_CFB = 0x0043, }; @@ -65,6 +67,8 @@ enum tpm_algorithms { enum tpm2_curves { TPM2_ECC_NONE = 0x0000, TPM2_ECC_NIST_P256 = 0x0003, + TPM2_ECC_NIST_P384 = 0x0004, + TPM2_ECC_NIST_P521 = 0x0005, }; struct tpm_digest { @@ -239,6 +243,7 @@ enum tpm2_structures { TPM2_ST_NO_SESSIONS = 0x8001, TPM2_ST_SESSIONS = 0x8002, TPM2_ST_CREATION = 0x8021, + TPM2_ST_HASHCHECK = 0x8024, }; /* Indicates from what layer of the software stack the error comes from */ @@ -274,6 +279,7 @@ enum tpm2_command_codes { TPM2_CC_LOAD = 0x0157, TPM2_CC_RSA_DECRYPT = 0x0159, TPM2_CC_SEQUENCE_UPDATE = 0x015C, + TPM2_CC_SIGN = 0x015D, TPM2_CC_UNSEAL = 0x015E, TPM2_CC_CONTEXT_LOAD = 0x0161, TPM2_CC_CONTEXT_SAVE = 0x0162,