From ad47f44f134fff952e20cd6e930c30210279023f Mon Sep 17 00:00:00 2001 From: Tianjia Zhang Date: Mon, 21 Sep 2020 00:21:02 +0800 Subject: [PATCH 2132/2944] X.509: support OSCCA SM2-with-SM3 certificate verification to #31026859 commit 215525639631ade1d67e879fe2c3d7195daa9f59 upstream The digital certificate format based on SM2 crypto algorithm as specified in GM/T 0015-2012. It was published by State Encryption Management Bureau, China. The method of generating Other User Information is defined as ZA=H256(ENTLA || IDA || a || b || xG || yG || xA || yA), it also specified in https://tools.ietf.org/html/draft-shen-sm2-ecdsa-02. The x509 certificate supports SM2-with-SM3 type certificate verification. Because certificate verification requires ZA in addition to tbs data, ZA also depends on elliptic curve parameters and public key data, so you need to access tbs in sig and calculate ZA. Finally calculate the digest of the signature and complete the verification work. The calculation process of ZA is declared in specifications GM/T 0009-2012 and GM/T 0003.2-2012. Signed-off-by: Tianjia Zhang Tested-by: Xufeng Zhang Reviewed-by: Gilad Ben-Yossef Signed-off-by: Herbert Xu Signed-off-by: Tianjia Zhang Reviewed-by: Jia Zhang --- crypto/asymmetric_keys/Makefile | 1 + crypto/asymmetric_keys/public_key.c | 6 ++++ crypto/asymmetric_keys/public_key_sm2.c | 61 ++++++++++++++++++++++++++++++++ crypto/asymmetric_keys/x509_public_key.c | 3 ++ include/crypto/public_key.h | 16 +++++++++ 5 files changed, 87 insertions(+) create mode 100644 crypto/asymmetric_keys/public_key_sm2.c diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile index d4b2e1b..9617e5f 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_PUBLIC_KEY_SUBTYPE) += public_key_sm2.o # # X.509 Certificate handling diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c index 355b4b0..af97f9e 100644 --- a/crypto/asymmetric_keys/public_key.c +++ b/crypto/asymmetric_keys/public_key.c @@ -109,6 +109,12 @@ int public_key_verify_signature(const struct public_key *pkey, if (ret) goto error_free_req; + if (strcmp(sig->pkey_algo, "sm2") == 0 && sig->data_size) { + ret = cert_sig_digest_update(sig, tfm); + if (ret) + goto error_free_req; + } + ret = -ENOMEM; digest = kmemdup(sig->digest, sig->digest_size, GFP_KERNEL); if (!digest) diff --git a/crypto/asymmetric_keys/public_key_sm2.c b/crypto/asymmetric_keys/public_key_sm2.c new file mode 100644 index 0000000..7325cf2 --- /dev/null +++ b/crypto/asymmetric_keys/public_key_sm2.c @@ -0,0 +1,61 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * asymmetric public-key algorithm for SM2-with-SM3 certificate + * as specified by OSCCA GM/T 0003.1-2012 -- 0003.5-2012 SM2 and + * described at https://tools.ietf.org/html/draft-shen-sm2-ecdsa-02 + * + * Copyright (c) 2020, Alibaba Group. + * Authors: Tianjia Zhang + */ + +#include +#include +#include + +#if IS_REACHABLE(CONFIG_CRYPTO_SM2) + +int cert_sig_digest_update(const struct public_key_signature *sig, + struct crypto_akcipher *tfm_pkey) +{ + struct crypto_shash *tfm; + struct shash_desc *desc; + size_t desc_size; + unsigned char dgst[SM3_DIGEST_SIZE]; + int ret; + + BUG_ON(!sig->data); + + ret = sm2_compute_z_digest(tfm_pkey, SM2_DEFAULT_USERID, + SM2_DEFAULT_USERID_LEN, dgst); + if (ret) + return ret; + + tfm = crypto_alloc_shash(sig->hash_algo, 0, 0); + if (IS_ERR(tfm)) + return PTR_ERR(tfm); + + desc_size = crypto_shash_descsize(tfm) + sizeof(*desc); + desc = kzalloc(desc_size, GFP_KERNEL); + if (!desc) + goto error_free_tfm; + + desc->tfm = tfm; + + ret = crypto_shash_init(desc); + if (ret < 0) + goto error_free_desc; + + ret = crypto_shash_update(desc, dgst, SM3_DIGEST_SIZE); + if (ret < 0) + goto error_free_desc; + + ret = crypto_shash_finup(desc, sig->data, sig->data_size, sig->digest); + +error_free_desc: + kfree(desc); +error_free_tfm: + crypto_free_shash(tfm); + return ret; +} + +#endif /* ! IS_REACHABLE(CONFIG_CRYPTO_SM2) */ diff --git a/crypto/asymmetric_keys/x509_public_key.c b/crypto/asymmetric_keys/x509_public_key.c index 9338b45..f76c455 100644 --- a/crypto/asymmetric_keys/x509_public_key.c +++ b/crypto/asymmetric_keys/x509_public_key.c @@ -34,6 +34,9 @@ int x509_get_sig_params(struct x509_certificate *cert) pr_devel("==>%s()\n", __func__); + sig->data = cert->tbs; + sig->data_size = cert->tbs_size; + if (!cert->pub->pkey_algo) cert->unsupported_key = true; diff --git a/include/crypto/public_key.h b/include/crypto/public_key.h index e0b681a..d19ff6c 100644 --- a/include/crypto/public_key.h +++ b/include/crypto/public_key.h @@ -14,6 +14,8 @@ #ifndef _LINUX_PUBLIC_KEY_H #define _LINUX_PUBLIC_KEY_H +#include + /* * Cryptographic data for the public-key subtype of the asymmetric key type. * @@ -40,6 +42,8 @@ struct public_key_signature { u8 digest_size; /* Number of bytes in digest */ const char *pkey_algo; const char *hash_algo; + const void *data; + unsigned int data_size; }; extern void public_key_signature_free(struct public_key_signature *sig); @@ -71,4 +75,16 @@ extern int verify_signature(const struct key *key, int public_key_verify_signature(const struct public_key *pkey, const struct public_key_signature *sig); +#if IS_REACHABLE(CONFIG_CRYPTO_SM2) +int cert_sig_digest_update(const struct public_key_signature *sig, + struct crypto_akcipher *tfm_pkey); +#else +static inline +int cert_sig_digest_update(const struct public_key_signature *sig, + struct crypto_akcipher *tfm_pkey) +{ + return -ENOTSUPP; +} +#endif + #endif /* _LINUX_PUBLIC_KEY_H */ -- 1.8.3.1