Linux-Modules Archive on lore.kernel.org
 help / color / Atom feed
From: Petko Manolov <petkan@mip-labs.com>
To: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: linux-security-module@vger.kernel.org,
	"Luis R. Rodriguez" <mcgrof@suse.com>,
	kexec@lists.infradead.org, linux-modules@vger.kernel.org,
	fsdevel@vger.kernel.org, David Howells <dhowells@redhat.com>,
	David Woodhouse <dwmw2@infradead.org>,
	Kees Cook <keescook@chromium.org>,
	Dmitry Torokhov <dmitry.torokhov@gmail.com>,
	Dmitry Kasatkin <dmitry.kasatkin@gmail.com>,
	Eric Biederman <ebiederm@xmission.com>,
	Rusty Russell <rusty@rustcorp.com.au>,
	Dmitry Kasatkin <d.kasatkin@samsung.com>,
	Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Subject: Re: [PATCH v3 20/22] ima: load policy using path
Date: Sun, 7 Feb 2016 21:59:45 +0200
Message-ID: <20160207195945.GG17321@localhost> (raw)
In-Reply-To: <1454526390-19792-21-git-send-email-zohar@linux.vnet.ibm.com>

On 16-02-03 14:06:28, Mimi Zohar wrote:
> From: Dmitry Kasatkin <d.kasatkin@samsung.com>
> 
> We currently cannot do appraisal or signature vetting of IMA policies
> since we currently can only load IMA policies by writing the contents
> of the policy directly in, as follows:
> 
> cat policy-file > <securityfs>/ima/policy
> 
> If we provide the kernel the path to the IMA policy so it can load
> the policy itself it'd be able to later appraise or vet the file
> signature if it has one.  This patch adds support to load the IMA
> policy with a given path as follows:
> 
> echo /etc/ima/ima_policy > /sys/kernel/security/ima/policy
> 
> Changelog v3:
> - moved kernel_read_file_from_path() to a separate patch
> v2:
> - after re-ordering the patches, replace calling integrity_kernel_read()
>   to read the file with kernel_read_file_from_path() (Mimi)
> - Patch description re-written by Luis R. Rodriguez
> 
> Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
> ---
>  include/linux/fs.h              |  1 +
>  security/integrity/ima/ima_fs.c | 43 +++++++++++++++++++++++++++++++++++++++--
>  2 files changed, 42 insertions(+), 2 deletions(-)
> 
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index d4d556e..b648e6d 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -2531,6 +2531,7 @@ enum kernel_read_file_id {
>  	READING_MODULE,
>  	READING_KEXEC_IMAGE,
>  	READING_KEXEC_INITRAMFS,
> +	READING_POLICY,
>  	READING_MAX_ID
>  };
>  
> diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c
> index f355231..00ccd67 100644
> --- a/security/integrity/ima/ima_fs.c
> +++ b/security/integrity/ima/ima_fs.c
> @@ -22,6 +22,7 @@
>  #include <linux/rculist.h>
>  #include <linux/rcupdate.h>
>  #include <linux/parser.h>
> +#include <linux/vmalloc.h>
>  
>  #include "ima.h"
>  
> @@ -258,6 +259,41 @@ static const struct file_operations ima_ascii_measurements_ops = {
>  	.release = seq_release,
>  };
>  
> +static ssize_t ima_read_policy(char *path)
> +{
> +	void *data;
> +	char *datap;
> +	loff_t size;
> +	int rc, pathlen = strlen(path);
> +
> +	char *p;
> +
> +	/* remove \n */
> +	datap = path;
> +	strsep(&datap, "\n");
> +
> +	rc = kernel_read_file_from_path(path, &data, &size, 0, READING_POLICY);
> +	if (rc < 0)
> +		return rc;
> +
> +	datap = data;
> +	while (size > 0 && (p = strsep(&datap, "\n"))) {
> +		pr_debug("rule: %s\n", p);
> +		rc = ima_parse_add_rule(p);
> +		if (rc < 0)
> +			break;
> +		size -= rc;
> +	}
> +
> +	vfree(data);
> +	if (rc < 0)
> +		return rc;
> +	else if (size)
> +		return -EINVAL;
> +	else
> +		return pathlen;
> +}
> +
>  static ssize_t ima_write_policy(struct file *file, const char __user *buf,
>  				size_t datalen, loff_t *ppos)
>  {
> @@ -286,9 +322,12 @@ static ssize_t ima_write_policy(struct file *file, const char __user *buf,
>  	result = mutex_lock_interruptible(&ima_write_mutex);
>  	if (result < 0)
>  		goto out_free;
> -	result = ima_parse_add_rule(data);
> -	mutex_unlock(&ima_write_mutex);
>  
> +	if (data[0] == '/')

It seems that if we feed relative path to ima_policy the update will fail...

> +		result = ima_read_policy(data);
> +	else
> +		result = ima_parse_add_rule(data);
> +	mutex_unlock(&ima_write_mutex);
>  out_free:
>  	kfree(data);
>  out:
> -- 
> 2.1.0
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-security-module" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

  reply index

Thread overview: 77+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-02-03 19:06 [PATCH v3 00/22] vfs: support for a common kernel file loader Mimi Zohar
2016-02-03 19:06 ` [PATCH v3 01/22] ima: separate 'security.ima' reading functionality from collect Mimi Zohar
2016-02-03 19:06 ` [PATCH v3 02/22] ima: refactor ima_policy_show() to display "ima_hooks" rules Mimi Zohar
2016-02-07 19:45   ` Petko Manolov
2016-02-10 19:33   ` Dmitry Kasatkin
2016-02-03 19:06 ` [PATCH v3 03/22] ima: use "ima_hooks" enum as function argument Mimi Zohar
2016-02-07 19:46   ` Petko Manolov
2016-02-10 19:35   ` Dmitry Kasatkin
2016-02-03 19:06 ` [PATCH v3 04/22] firmware: simplify dev_*() print messages for generic helpers Mimi Zohar
2016-02-04 17:26   ` Kees Cook
2016-02-03 19:06 ` [PATCH v3 05/22] firmware: move completing fw into a helper Mimi Zohar
2016-02-04 17:27   ` Kees Cook
2016-02-03 19:06 ` [PATCH v3 06/22] firmware: fold successful fw read early Mimi Zohar
2016-02-04 17:36   ` Kees Cook
2016-02-04 20:26     ` Luis R. Rodriguez
2016-02-03 19:06 ` [PATCH v3 07/22] vfs: define a generic function to read a file from the kernel Mimi Zohar
2016-02-04 17:41   ` Kees Cook
2016-02-03 19:06 ` [PATCH v3 08/22] vfs: define kernel_read_file_id enumeration Mimi Zohar
2016-02-04 17:41   ` Kees Cook
2016-02-04 19:45   ` Luis R. Rodriguez
2016-02-03 19:06 ` [PATCH v3 09/22] ima: provide buffer hash calculation function Mimi Zohar
2016-02-03 19:06 ` [PATCH v3 10/22] ima: calculate the hash of a buffer using aynchronous hash(ahash) Mimi Zohar
2016-02-10 19:58   ` Dmitry Kasatkin
2016-02-03 19:06 ` [PATCH v3 11/22] ima: define a new hook to measure and appraise a file already in memory Mimi Zohar
2016-02-10 20:27   ` Dmitry Kasatkin
2016-02-03 19:06 ` [PATCH v3 12/22] vfs: define kernel_read_file_from_path Mimi Zohar
2016-02-04 17:46   ` Kees Cook
2016-02-04 19:47   ` Luis R. Rodriguez
2016-02-03 19:06 ` [PATCH v3 13/22] firmware: replace call to fw_read_file_contents() with kernel version Mimi Zohar
2016-02-04 17:56   ` Kees Cook
2016-02-04 19:51   ` Luis R. Rodriguez
2016-02-03 19:06 ` [PATCH v3 14/22] security: define kernel_read_file hook Mimi Zohar
2016-02-04 17:57   ` Kees Cook
2016-02-04 19:54   ` Luis R. Rodriguez
2016-02-11 16:54   ` Casey Schaufler
2016-02-11 19:35     ` Mimi Zohar
2016-02-03 19:06 ` [PATCH v3 15/22] vfs: define kernel_copy_file_from_fd() Mimi Zohar
2016-02-04 17:58   ` Kees Cook
2016-02-04 19:55   ` Luis R. Rodriguez
2016-02-03 19:06 ` [PATCH v3 16/22] module: replace copy_module_from_fd with kernel version Mimi Zohar
2016-02-04 18:04   ` Kees Cook
2016-02-04 19:56   ` Luis R. Rodriguez
2016-02-05  0:19     ` Mimi Zohar
2016-02-03 19:06 ` [PATCH v3 17/22] ima: remove firmware and module specific cached status info Mimi Zohar
2016-02-07 19:56   ` Petko Manolov
2016-02-10 20:18   ` Dmitry Kasatkin
2016-02-10 23:14     ` Mimi Zohar
2016-02-03 19:06 ` [PATCH v3 18/22] kexec: replace call to copy_file_from_fd() with kernel version Mimi Zohar
2016-02-04 18:05   ` Kees Cook
2016-02-04 19:57   ` Luis R. Rodriguez
2016-02-12 12:50   ` Dave Young
2016-02-03 19:06 ` [PATCH v3 19/22] ima: support for kexec image and initramfs Mimi Zohar
2016-02-07 20:10   ` Petko Manolov
2016-02-08 23:34     ` Mimi Zohar
2016-02-10 21:09   ` Dmitry Kasatkin
2016-02-10 23:21     ` Mimi Zohar
     [not found]       ` <CACE9dm8OJ1cgbKszUG-pCiEMVarUFLLWi_jewVV-JEMGAJsA-g@mail.gmail.com>
2016-02-11  2:08         ` Mimi Zohar
2016-02-11  8:47           ` Dmitry Kasatkin
2016-02-11 12:16             ` Mimi Zohar
2016-02-12 12:53   ` Dave Young
2016-02-12 13:09     ` Mimi Zohar
2016-02-03 19:06 ` [PATCH v3 20/22] ima: load policy using path Mimi Zohar
2016-02-07 19:59   ` Petko Manolov [this message]
2016-02-08  9:58     ` Dmitry Kasatkin
2016-02-08 10:35       ` Petko Manolov
2016-02-08 10:45         ` Dmitry Kasatkin
2016-02-08 21:12           ` Mimi Zohar
2016-02-09  7:47             ` Petko Manolov
2016-02-03 19:06 ` [PATCH v3 21/22] ima: measure and appraise the IMA policy itself Mimi Zohar
2016-02-07 20:01   ` Petko Manolov
2016-02-10 20:22   ` Dmitry Kasatkin
2016-02-10 23:15     ` Mimi Zohar
2016-02-03 19:06 ` [PATCH v3 22/22] ima: require signed IMA policy Mimi Zohar
2016-02-07 20:02   ` Petko Manolov
2016-02-10 20:24   ` Dmitry Kasatkin
2016-02-04 18:15 ` [PATCH v3 00/22] vfs: support for a common kernel file loader Kees Cook
2016-02-04 23:54   ` 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=20160207195945.GG17321@localhost \
    --to=petkan@mip-labs.com \
    --cc=d.kasatkin@samsung.com \
    --cc=dhowells@redhat.com \
    --cc=dmitry.kasatkin@gmail.com \
    --cc=dmitry.kasatkin@huawei.com \
    --cc=dmitry.torokhov@gmail.com \
    --cc=dwmw2@infradead.org \
    --cc=ebiederm@xmission.com \
    --cc=fsdevel@vger.kernel.org \
    --cc=keescook@chromium.org \
    --cc=kexec@lists.infradead.org \
    --cc=linux-modules@vger.kernel.org \
    --cc=linux-security-module@vger.kernel.org \
    --cc=mcgrof@suse.com \
    --cc=rusty@rustcorp.com.au \
    --cc=zohar@linux.vnet.ibm.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-Modules Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-modules/0 linux-modules/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-modules linux-modules/ https://lore.kernel.org/linux-modules \
		linux-modules@vger.kernel.org linux-modules@archiver.kernel.org
	public-inbox-index linux-modules


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


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