Linux-EFI Archive on lore.kernel.org
 help / color / Atom feed
From: Mimi Zohar <zohar@linux.ibm.com>
To: Nayna Jain <nayna@linux.ibm.com>,
	linuxppc-dev@ozlabs.org, linux-efi@vger.kernel.org,
	linux-integrity@vger.kernel.org
Cc: linux-kernel@vger.kernel.org,
	Michael Ellerman <mpe@ellerman.id.au>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Paul Mackerras <paulus@samba.org>,
	Ard Biesheuvel <ard.biesheuvel@linaro.org>,
	Jeremy Kerr <jk@ozlabs.org>,
	Matthew Garret <matthew.garret@nebula.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Claudio Carvalho <cclaudio@linux.ibm.com>,
	George Wilson <gcwilson@linux.ibm.com>,
	Elaine Palmer <erpalmer@us.ibm.com>,
	Eric Ricther <erichte@linux.ibm.com>,
	"Oliver O'Halloran" <oohall@gmail.com>,
	Prakhar Srivastava <prsriva02@gmail.com>
Subject: Re: [PATCH v7 5/8] ima: make process_buffer_measurement() generic
Date: Fri, 11 Oct 2019 09:14:01 -0400
Message-ID: <1570799641.5250.75.camel@linux.ibm.com> (raw)
In-Reply-To: <1570497267-13672-6-git-send-email-nayna@linux.ibm.com>

[Cc'ing Prakhar Srivastava]

On Mon, 2019-10-07 at 21:14 -0400, Nayna Jain wrote:
> An additional measurement record is needed to indicate the blacklisted
> binary. The record will measure the blacklisted binary hash.
> 
> This patch makes the function process_buffer_measurement() generic to be
> called by the blacklisting function. It modifies the function to handle
> more than just the KEXEC_CMDLINE.

The purpose of this patch is to make process_buffer_measurement() more
generic.  The patch description should simply say,
process_buffer_measurement() is limited to measuring the kexec boot
command line.  This patch makes process_buffer_measurement() more
generic, allowing it to measure other types of buffer data (eg.
blacklisted binary hashes).

Mimi

> 
> Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
> ---
>  security/integrity/ima/ima.h      |  3 +++
>  security/integrity/ima/ima_main.c | 29 ++++++++++++++---------------
>  2 files changed, 17 insertions(+), 15 deletions(-)
> 
> diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
> index 3689081aaf38..ed86c1f70d7f 100644
> --- a/security/integrity/ima/ima.h
> +++ b/security/integrity/ima/ima.h
> @@ -217,6 +217,9 @@ void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file,
>  			   struct evm_ima_xattr_data *xattr_value,
>  			   int xattr_len, const struct modsig *modsig, int pcr,
>  			   struct ima_template_desc *template_desc);
> +void process_buffer_measurement(const void *buf, int size,
> +				const char *eventname, int pcr,
> +				struct ima_template_desc *template_desc);
>  void ima_audit_measurement(struct integrity_iint_cache *iint,
>  			   const unsigned char *filename);
>  int ima_alloc_init_template(struct ima_event_data *event_data,
> diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
> index 60027c643ecd..77115e884496 100644
> --- a/security/integrity/ima/ima_main.c
> +++ b/security/integrity/ima/ima_main.c
> @@ -626,14 +626,14 @@ int ima_load_data(enum kernel_load_data_id id)
>   * @buf: pointer to the buffer that needs to be added to the log.
>   * @size: size of buffer(in bytes).
>   * @eventname: event name to be used for the buffer entry.
> - * @cred: a pointer to a credentials structure for user validation.
> - * @secid: the secid of the task to be validated.
> + * @pcr: pcr to extend the measurement
> + * @template_desc: template description
>   *
>   * Based on policy, the buffer is measured into the ima log.
>   */
> -static void process_buffer_measurement(const void *buf, int size,
> -				       const char *eventname,
> -				       const struct cred *cred, u32 secid)
> +void process_buffer_measurement(const void *buf, int size,
> +				const char *eventname, int pcr,
> +				struct ima_template_desc *template_desc)
>  {
>  	int ret = 0;
>  	struct ima_template_entry *entry = NULL;
> @@ -642,19 +642,11 @@ static void process_buffer_measurement(const void *buf, int size,
>  					    .filename = eventname,
>  					    .buf = buf,
>  					    .buf_len = size};
> -	struct ima_template_desc *template_desc = NULL;
>  	struct {
>  		struct ima_digest_data hdr;
>  		char digest[IMA_MAX_DIGEST_SIZE];
>  	} hash = {};
>  	int violation = 0;
> -	int pcr = CONFIG_IMA_MEASURE_PCR_IDX;
> -	int action = 0;
> -
> -	action = ima_get_action(NULL, cred, secid, 0, KEXEC_CMDLINE, &pcr,
> -				&template_desc);
> -	if (!(action & IMA_MEASURE))
> -		return;
>  
>  	iint.ima_hash = &hash.hdr;
>  	iint.ima_hash->algo = ima_hash_algo;
> @@ -686,12 +678,19 @@ static void process_buffer_measurement(const void *buf, int size,
>   */
>  void ima_kexec_cmdline(const void *buf, int size)
>  {
> +	int pcr = CONFIG_IMA_MEASURE_PCR_IDX;
> +	struct ima_template_desc *template_desc = NULL;
> +	int action;
>  	u32 secid;
>  
>  	if (buf && size != 0) {
>  		security_task_getsecid(current, &secid);
> -		process_buffer_measurement(buf, size, "kexec-cmdline",
> -					   current_cred(), secid);
> +		action = ima_get_action(NULL, current_cred(), secid, 0,
> +					KEXEC_CMDLINE, &pcr, &template_desc);
> +		if (!(action & IMA_MEASURE))
> +			return;
> +		process_buffer_measurement(buf, size, "kexec-cmdline", pcr,
> +					   template_desc);
>  	}
>  }
>  


  reply index

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-08  1:14 [PATCH v7 0/8] powerpc: Enabling IMA arch specific secure boot policies Nayna Jain
2019-10-08  1:14 ` [PATCH v7 1/8] powerpc: detect the secure boot mode of the system Nayna Jain
2019-10-15 11:30   ` Michael Ellerman
2019-10-08  1:14 ` [PATCH v7 2/8] powerpc: add support to initialize ima policy rules Nayna Jain
2019-10-11 13:12   ` Mimi Zohar
2019-10-15  9:59     ` Michael Ellerman
2019-10-15 11:29   ` Michael Ellerman
2019-10-17 12:58     ` Nayna
2019-10-08  1:14 ` [PATCH v7 3/8] powerpc: detect the trusted boot state of the system Nayna Jain
2019-10-15 10:23   ` Michael Ellerman
2019-10-08  1:14 ` [PATCH v7 4/8] powerpc/ima: add measurement rules to ima arch specific policy Nayna Jain
2019-10-15 11:29   ` Michael Ellerman
2019-10-19 18:27     ` Nayna
2019-10-08  1:14 ` [PATCH v7 5/8] ima: make process_buffer_measurement() generic Nayna Jain
2019-10-11 13:14   ` Mimi Zohar [this message]
2019-10-08  1:14 ` [PATCH v7 6/8] certs: add wrapper function to check blacklisted binary hash Nayna Jain
2019-10-11 13:18   ` Mimi Zohar
2019-10-08  1:14 ` [PATCH v7 7/8] ima: check against blacklisted hashes for files with modsig Nayna Jain
2019-10-11 13:19   ` Mimi Zohar
2019-10-19 18:30     ` Nayna
2019-10-08  1:14 ` [PATCH v7 8/8] powerpc/ima: update ima arch policy to check for blacklist Nayna Jain
2019-10-11 13:19   ` Mimi Zohar

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1570799641.5250.75.camel@linux.ibm.com \
    --to=zohar@linux.ibm.com \
    --cc=ard.biesheuvel@linaro.org \
    --cc=benh@kernel.crashing.org \
    --cc=cclaudio@linux.ibm.com \
    --cc=erichte@linux.ibm.com \
    --cc=erpalmer@us.ibm.com \
    --cc=gcwilson@linux.ibm.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=jk@ozlabs.org \
    --cc=linux-efi@vger.kernel.org \
    --cc=linux-integrity@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linuxppc-dev@ozlabs.org \
    --cc=matthew.garret@nebula.com \
    --cc=mpe@ellerman.id.au \
    --cc=nayna@linux.ibm.com \
    --cc=oohall@gmail.com \
    --cc=paulus@samba.org \
    --cc=prsriva02@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-EFI Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-efi/0 linux-efi/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-efi linux-efi/ https://lore.kernel.org/linux-efi \
		linux-efi@vger.kernel.org linux-efi@archiver.kernel.org
	public-inbox-index linux-efi

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-efi


AGPL code for this site: git clone https://public-inbox.org/ public-inbox