Re: [PATCH v5 4/8] ima: define a new template field 'd-type' and a new template 'ima-ngv2'

[Stefan Berger <stefanb@linux.ibm.com>]

On 2/11/22 16:43, Mimi Zohar wrote:
> In preparation to differentiate between regular IMA file hashes and
> fs-verity's file digests, define a new template field named 'd-type'.
> Define a new template named 'ima-ngv2', which includes the new 'd-type'
> field.
>
> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
> ---
>   security/integrity/ima/ima_template.c     |  3 +++
>   security/integrity/ima/ima_template_lib.c | 13 +++++++++++++
>   security/integrity/ima/ima_template_lib.h |  2 ++
>   3 files changed, 18 insertions(+)
>
> diff --git a/security/integrity/ima/ima_template.c b/security/integrity/ima/ima_template.c
> index db1ad6d7a57f..b321342e5bee 100644
> --- a/security/integrity/ima/ima_template.c
> +++ b/security/integrity/ima/ima_template.c
> @@ -19,6 +19,7 @@ enum header_fields { HDR_PCR, HDR_DIGEST, HDR_TEMPLATE_NAME,
>   static struct ima_template_desc builtin_templates[] = {
>   	{.name = IMA_TEMPLATE_IMA_NAME, .fmt = IMA_TEMPLATE_IMA_FMT},
>   	{.name = "ima-ng", .fmt = "d-ng|n-ng"},
> +	{.name = "ima-ngv2", .fmt = "d-ng|n-ng|d-type"},
>   	{.name = "ima-sig", .fmt = "d-ng|n-ng|sig"},
>   	{.name = "ima-buf", .fmt = "d-ng|n-ng|buf"},
>   	{.name = "ima-modsig", .fmt = "d-ng|n-ng|sig|d-modsig|modsig"},
> @@ -40,6 +41,8 @@ static const struct ima_template_field supported_fields[] = {
>   	 .field_show = ima_show_template_digest_ng},
>   	{.field_id = "n-ng", .field_init = ima_eventname_ng_init,
>   	 .field_show = ima_show_template_string},
> +	{.field_id = "d-type", .field_init = ima_eventdigest_type_init,
> +	 .field_show = ima_show_template_string},
>   	{.field_id = "sig", .field_init = ima_eventsig_init,
>   	 .field_show = ima_show_template_sig},
>   	{.field_id = "buf", .field_init = ima_eventbuf_init,
> diff --git a/security/integrity/ima/ima_template_lib.c b/security/integrity/ima/ima_template_lib.c
> index 7155d17a3b75..a213579e825e 100644
> --- a/security/integrity/ima/ima_template_lib.c
> +++ b/security/integrity/ima/ima_template_lib.c
> @@ -383,6 +383,19 @@ int ima_eventdigest_ng_init(struct ima_event_data *event_data,
>   					   hash_algo, field_data);
>   }
>   
> +/*
> + * This function writes the digest type of an event.
> + */
> +int ima_eventdigest_type_init(struct ima_event_data *event_data,
> +			      struct ima_field_data *field_data)
> +{
> +	static const char * const digest_type[] = {"ima"};

This array makes sense with 6/8.

Acked-by: Stefan Berger <stefanb@linux.ibm.com>


> +
> +	return ima_write_template_field_data(digest_type[0],
> +					     strlen(digest_type[0]),
> +					     DATA_FMT_STRING, field_data);
> +}
> +
>   /*
>    * This function writes the digest of the file which is expected to match the
>    * digest contained in the file's appended signature.
> diff --git a/security/integrity/ima/ima_template_lib.h b/security/integrity/ima/ima_template_lib.h
> index c71f1de95753..539a5e354925 100644
> --- a/security/integrity/ima/ima_template_lib.h
> +++ b/security/integrity/ima/ima_template_lib.h
> @@ -38,6 +38,8 @@ int ima_eventname_init(struct ima_event_data *event_data,
>   		       struct ima_field_data *field_data);
>   int ima_eventdigest_ng_init(struct ima_event_data *event_data,
>   			    struct ima_field_data *field_data);
> +int ima_eventdigest_type_init(struct ima_event_data *event_data,
> +			      struct ima_field_data *field_data);
>   int ima_eventdigest_modsig_init(struct ima_event_data *event_data,
>   				struct ima_field_data *field_data);
>   int ima_eventname_ng_init(struct ima_event_data *event_data,