[PATCH v6 6/8] X.509: support OSCCA certificate parse

[Vitaly Chikunov]

On Thu, Sep 03, 2020 at 09:12:40PM +0800, Tianjia Zhang wrote:
> 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.
> 
> This patch adds the OID object identifier defined by OSCCA. The
> x509 certificate supports sm2-with-sm3 type certificate parsing.
> It uses the standard elliptic curve public key, and the sm2
> algorithm signs the hash generated by sm3.
> 
> Signed-off-by: Tianjia Zhang <tianjia.zhang at linux.alibaba.com>
> Tested-by: Xufeng Zhang <yunbo.xufeng at linux.alibaba.com>
> ---
>  crypto/asymmetric_keys/x509_cert_parser.c | 14 +++++++++++++-
>  include/linux/oid_registry.h              |  6 ++++++
>  2 files changed, 19 insertions(+), 1 deletion(-)
> 
> diff --git a/crypto/asymmetric_keys/x509_cert_parser.c b/crypto/asymmetric_keys/x509_cert_parser.c
> index 26ec20ef4899..6a8aee22bfd4 100644
> --- a/crypto/asymmetric_keys/x509_cert_parser.c
> +++ b/crypto/asymmetric_keys/x509_cert_parser.c
> @@ -234,6 +234,10 @@ int x509_note_pkey_algo(void *context, size_t hdrlen,
>  	case OID_gost2012Signature512:
>  		ctx->cert->sig->hash_algo = "streebog512";
>  		goto ecrdsa;
> +
> +	case OID_sm2_with_sm3:
> +		ctx->cert->sig->hash_algo = "sm3";
> +		goto sm2;
>  	}
>  
>  rsa_pkcs1:
> @@ -246,6 +250,11 @@ int x509_note_pkey_algo(void *context, size_t hdrlen,
>  	ctx->cert->sig->encoding = "raw";
>  	ctx->algo_oid = ctx->last_oid;
>  	return 0;
> +sm2:
> +	ctx->cert->sig->pkey_algo = "sm2";
> +	ctx->cert->sig->encoding = "raw";
> +	ctx->algo_oid = ctx->last_oid;
> +	return 0;
>  }
>  
>  /*
> @@ -266,7 +275,8 @@ int x509_note_signature(void *context, size_t hdrlen,
>  	}
>  
>  	if (strcmp(ctx->cert->sig->pkey_algo, "rsa") == 0 ||
> -	    strcmp(ctx->cert->sig->pkey_algo, "ecrdsa") == 0) {
> +	    strcmp(ctx->cert->sig->pkey_algo, "ecrdsa") == 0 ||
> +	    strcmp(ctx->cert->sig->pkey_algo, "sm2") == 0) {
>  		/* Discard the BIT STRING metadata */
>  		if (vlen < 1 || *(const u8 *)value != 0)
>  			return -EBADMSG;
> @@ -456,6 +466,8 @@ int x509_extract_key_data(void *context, size_t hdrlen,
>  	else if (ctx->last_oid == OID_gost2012PKey256 ||
>  		 ctx->last_oid == OID_gost2012PKey512)
>  		ctx->cert->pub->pkey_algo = "ecrdsa";
> +	else if (ctx->last_oid == OID_id_ecPublicKey)
> +		ctx->cert->pub->pkey_algo = "sm2";
>  	else
>  		return -ENOPKG;
>  
> diff --git a/include/linux/oid_registry.h b/include/linux/oid_registry.h
> index 657d6bf2c064..48fe3133ff39 100644
> --- a/include/linux/oid_registry.h
> +++ b/include/linux/oid_registry.h
> @@ -107,6 +107,12 @@ enum OID {
>  	OID_gostTC26Sign512B,		/* 1.2.643.7.1.2.1.2.2 */
>  	OID_gostTC26Sign512C,		/* 1.2.643.7.1.2.1.2.3 */
>  
> +	/* OSCCA */
> +	OID_sm2,			/* 1.2.156.10197.1.301 */
> +	OID_sm3,			/* 1.2.156.10197.1.401 */
> +	OID_sm2_with_sm3,		/* 1.2.156.10197.1.501 */
> +	OID_sm3WithRSAEncryption,	/* 1.2.156.10197.1.504 */

OID_sm3WithRSAEncryption identifier is unused and this mode looks not
implemented. But, this is probably ok for possible future extension.

Reviewed-by: Vitaly Chikunov <vt at altlinux.org>

Thanks,


> +
>  	OID__NR
>  };
>