On Thu, 28 Sep 2023 19:32:32 +0200
Lukas Wunner <lukas@xxxxxxxxx> wrote:
> The upcoming support for PCI device authentication with CMA-SPDM
> (PCIe r6.1 sec 6.31) requires validating the Subject Alternative Name
> in X.509 certificates.
>
> Store a pointer to the Subject Alternative Name upon parsing for
> consumption by CMA-SPDM.
>
> Signed-off-by: Lukas Wunner <lukas@xxxxxxxxx>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
> ---
> crypto/asymmetric_keys/x509_cert_parser.c | 15 +++++++++++++++
> include/keys/x509-parser.h | 2 ++
> 2 files changed, 17 insertions(+)
>
> diff --git a/crypto/asymmetric_keys/x509_cert_parser.c b/crypto/asymmetric_keys/x509_cert_parser.c
> index 0a7049b470c1..18dfd564740b 100644
> --- a/crypto/asymmetric_keys/x509_cert_parser.c
> +++ b/crypto/asymmetric_keys/x509_cert_parser.c
> @@ -579,6 +579,21 @@ int x509_process_extension(void *context, size_t hdrlen,
> return 0;
> }
>
> + if (ctx->last_oid == OID_subjectAltName) {
> + /*
> + * A certificate MUST NOT include more than one instance
> + * of a particular extension (RFC 5280 sec 4.2).
> + */
> + if (ctx->cert->raw_san) {
> + pr_err("Duplicate Subject Alternative Name\n");
> + return -EINVAL;
> + }
> +
> + ctx->cert->raw_san = v;
> + ctx->cert->raw_san_size = vlen;
> + return 0;
> + }
> +
> if (ctx->last_oid == OID_keyUsage) {
> /*
> * Get hold of the keyUsage bit string
> diff --git a/include/keys/x509-parser.h b/include/keys/x509-parser.h
> index 7c2ebc84791f..9c6e7cdf4870 100644
> --- a/include/keys/x509-parser.h
> +++ b/include/keys/x509-parser.h
> @@ -32,6 +32,8 @@ struct x509_certificate {
> unsigned raw_subject_size;
> unsigned raw_skid_size;
> const void *raw_skid; /* Raw subjectKeyId in ASN.1 */
> + const void *raw_san; /* Raw subjectAltName in ASN.1 */
> + unsigned raw_san_size;
> unsigned index;
> bool seen; /* Infinite recursion prevention */
> bool verified;
