[PATCH 0/2] checkmodule: allow building modules of a specific version

[PATCH 0/2] checkmodule: allow building modules of a specific version

[Gary Tierney]

These changes come from a report by a user on the Freenode IRC channel that
they were unable to build policies for a machine that has an older version of
libsepol installed.

A new `-c` option that mirrors checkpolicy's own has been added to checkmodule,
and the output of a simple test is shown below:

$ cat > test.te <<EOF
module test 1.0;

require {
    type domain;
    type file_type;
    class file { read write };
}

allow domain file_type : file { read write };
EOF
$ obj/usr/bin/checkmodule -m -M -c 10 -o test.mod test.te
$ checkpolicy/test/dismod test.mod
Reading policy...
... snip ...
Binary policy module file loaded.
Module name: test
Module version: 1.0
Policy version: 10

Worthy of note, however, is that these policy version numbers differ from those
used by the kernel policy format.

Gary Tierney (2):
  checkmodule: add support for specifying module policy version
  dismod: print policy version of loaded modules

 checkpolicy/checkmodule.8 |  5 ++++-
 checkpolicy/checkmodule.c | 29 +++++++++++++++++++++++++++--
 checkpolicy/test/dismod.c |  4 ++--
 3 files changed, 33 insertions(+), 5 deletions(-)

-- 
2.17.2

[PATCH 1/2] checkmodule: add support for specifying module policy version

[Gary Tierney]

Currently checkpolicy can produce binary policies for earlier policy versions
to provide support for building policies on one machine and loading/analyzing
them on another machine with an earlier version of the kernel or libsepol,
respectively. However, checkmodule was lacking this capability.

This commit adds an identical `-c` flag that can be passed to checkmodule that
will build a modular policy file of the specified version.

Signed-off-by: Gary Tierney <gary.tierney@fastmail.com>
---
 checkpolicy/checkmodule.8 |  5 ++++-
 checkpolicy/checkmodule.c | 29 +++++++++++++++++++++++++++--
 2 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/checkpolicy/checkmodule.8 b/checkpolicy/checkmodule.8
index cf76591c24d0..e55582f30ec0 100644
--- a/checkpolicy/checkmodule.8
+++ b/checkpolicy/checkmodule.8
@@ -38,7 +38,7 @@ Generate a non-base policy module.
 Enable the MLS/MCS support when checking and compiling the policy module.
 .TP
 .B \-V,\-\-version
- Show policy versions created by this program.  Note that you cannot currently build older versions.
+Show policy versions created by this program.
 .TP
 .B \-o,\-\-output filename
 Write a binary policy module file to the specified filename.
@@ -47,6 +47,9 @@ and will not generate a binary module at all.
 .TP
 .B \-U,\-\-handle-unknown <action>
 Specify how the kernel should handle unknown classes or permissions (deny, allow or reject).
+.TP
+.B \-c policyvers
+Specify the policy version, defaults to the latest.
 
 .SH EXAMPLE
 .nf
diff --git a/checkpolicy/checkmodule.c b/checkpolicy/checkmodule.c
index 8edc1f8c7bbd..3bb9e5a4a6b3 100644
--- a/checkpolicy/checkmodule.c
+++ b/checkpolicy/checkmodule.c
@@ -142,6 +142,8 @@ static __attribute__((__noreturn__)) void usage(const char *progname)
 	printf("  -m         build a policy module instead of a base module\n");
 	printf("  -M         enable MLS policy\n");
 	printf("  -o FILE    write module to FILE (else just check syntax)\n");
+	printf("  -c VERSION build a policy module targeting a modular policy version (%d-%d)\n",
+	       MOD_POLICYDB_VERSION_MIN, MOD_POLICYDB_VERSION_MAX);
 	exit(1);
 }
 
@@ -163,7 +165,7 @@ int main(int argc, char **argv)
 		{NULL, 0, NULL, 0}
 	};
 
-	while ((ch = getopt_long(argc, argv, "ho:bVU:mMC", long_options, NULL)) != -1) {
+	while ((ch = getopt_long(argc, argv, "ho:bVU:mMCc:", long_options, NULL)) != -1) {
 		switch (ch) {
 		case 'h':
 			usage(argv[0]);
@@ -194,7 +196,6 @@ int main(int argc, char **argv)
 			usage(argv[0]);
 		case 'm':
 			policy_type = POLICY_MOD;
-			policyvers = MOD_POLICYDB_VERSION_MAX;
 			break;
 		case 'M':
 			mlspol = 1;
@@ -202,6 +203,30 @@ int main(int argc, char **argv)
 		case 'C':
 			cil = 1;
 			break;
+		case 'c': {
+			long int n;
+			errno = 0;
+			n = strtol(optarg, NULL, 10);
+
+			if (errno) {
+				fprintf(stderr,
+					"Invalid policyvers specified: %s\n",
+					optarg);
+				usage(argv[0]);
+			}
+
+			if (n < MOD_POLICYDB_VERSION_MIN
+			    || n > MOD_POLICYDB_VERSION_MAX) {
+				fprintf(stderr,
+					"policyvers value %ld not in range %d-%d\n",
+					n, MOD_POLICYDB_VERSION_MIN,
+					MOD_POLICYDB_VERSION_MAX);
+				usage(argv[0]);
+			}
+
+			policyvers = n;
+			break;
+		}
 		default:
 			usage(argv[0]);
 		}
-- 
2.17.2

Re: [PATCH 1/2] checkmodule: add support for specifying module policy version

[William Roberts]

On Wed, Apr 17, 2019 at 9:37 AM Gary Tierney <gary.tierney@fastmail.com> wrote:
>
> Currently checkpolicy can produce binary policies for earlier policy versions
> to provide support for building policies on one machine and loading/analyzing
> them on another machine with an earlier version of the kernel or libsepol,
> respectively. However, checkmodule was lacking this capability.
>
> This commit adds an identical `-c` flag that can be passed to checkmodule that
> will build a modular policy file of the specified version.
>
> Signed-off-by: Gary Tierney <gary.tierney@fastmail.com>
> ---
>  checkpolicy/checkmodule.8 |  5 ++++-
>  checkpolicy/checkmodule.c | 29 +++++++++++++++++++++++++++--
>  2 files changed, 31 insertions(+), 3 deletions(-)
>
> diff --git a/checkpolicy/checkmodule.8 b/checkpolicy/checkmodule.8
> index cf76591c24d0..e55582f30ec0 100644
> --- a/checkpolicy/checkmodule.8
> +++ b/checkpolicy/checkmodule.8
> @@ -38,7 +38,7 @@ Generate a non-base policy module.
>  Enable the MLS/MCS support when checking and compiling the policy module.
>  .TP
>  .B \-V,\-\-version
> - Show policy versions created by this program.  Note that you cannot currently build older versions.
> +Show policy versions created by this program.
>  .TP
>  .B \-o,\-\-output filename
>  Write a binary policy module file to the specified filename.
> @@ -47,6 +47,9 @@ and will not generate a binary module at all.
>  .TP
>  .B \-U,\-\-handle-unknown <action>
>  Specify how the kernel should handle unknown classes or permissions (deny, allow or reject).
> +.TP
> +.B \-c policyvers
> +Specify the policy version, defaults to the latest.
>
>  .SH EXAMPLE
>  .nf
> diff --git a/checkpolicy/checkmodule.c b/checkpolicy/checkmodule.c
> index 8edc1f8c7bbd..3bb9e5a4a6b3 100644
> --- a/checkpolicy/checkmodule.c
> +++ b/checkpolicy/checkmodule.c
> @@ -142,6 +142,8 @@ static __attribute__((__noreturn__)) void usage(const char *progname)
>         printf("  -m         build a policy module instead of a base module\n");
>         printf("  -M         enable MLS policy\n");
>         printf("  -o FILE    write module to FILE (else just check syntax)\n");
> +       printf("  -c VERSION build a policy module targeting a modular policy version (%d-%d)\n",
> +              MOD_POLICYDB_VERSION_MIN, MOD_POLICYDB_VERSION_MAX);
>         exit(1);
>  }
>
> @@ -163,7 +165,7 @@ int main(int argc, char **argv)
>                 {NULL, 0, NULL, 0}
>         };
>
> -       while ((ch = getopt_long(argc, argv, "ho:bVU:mMC", long_options, NULL)) != -1) {
> +       while ((ch = getopt_long(argc, argv, "ho:bVU:mMCc:", long_options, NULL)) != -1) {
>                 switch (ch) {
>                 case 'h':
>                         usage(argv[0]);
> @@ -194,7 +196,6 @@ int main(int argc, char **argv)
>                         usage(argv[0]);
>                 case 'm':
>                         policy_type = POLICY_MOD;
> -                       policyvers = MOD_POLICYDB_VERSION_MAX;
>                         break;
>                 case 'M':
>                         mlspol = 1;
> @@ -202,6 +203,30 @@ int main(int argc, char **argv)
>                 case 'C':
>                         cil = 1;
>                         break;
> +               case 'c': {
> +                       long int n;
> +                       errno = 0;
> +                       n = strtol(optarg, NULL, 10);
> +
> +                       if (errno) {

Get rid of this newline between the strtol() and errno.

> +                               fprintf(stderr,
> +                                       "Invalid policyvers specified: %s\n",
> +                                       optarg);
> +                               usage(argv[0]);
> +                       }
> +
> +                       if (n < MOD_POLICYDB_VERSION_MIN
> +                           || n > MOD_POLICYDB_VERSION_MAX) {
> +                               fprintf(stderr,
> +                                       "policyvers value %ld not in range %d-%d\n",
> +                                       n, MOD_POLICYDB_VERSION_MIN,
> +                                       MOD_POLICYDB_VERSION_MAX);
> +                               usage(argv[0]);
> +                       }
> +
> +                       policyvers = n;
> +                       break;
> +               }
>                 default:
>                         usage(argv[0]);
>                 }
> --
> 2.17.2
>

[PATCH 2/2] dismod: print policy version of loaded modules

[Gary Tierney]

Signed-off-by: Gary Tierney <gary.tierney@fastmail.com>
---
 checkpolicy/test/dismod.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/checkpolicy/test/dismod.c b/checkpolicy/test/dismod.c
index d5c7eeab093a..075bd85df4e6 100644
--- a/checkpolicy/test/dismod.c
+++ b/checkpolicy/test/dismod.c
@@ -903,14 +903,14 @@ int main(int argc, char **argv)
 	}
 
 	if (policydb.policy_type == POLICY_BASE) {
-		printf("Binary base policy file loaded.\n\n");
+		printf("Binary base policy file loaded.\n");
 	} else {
 		printf("Binary policy module file loaded.\n");
 		printf("Module name: %s\n", policydb.name);
 		printf("Module version: %s\n", policydb.version);
-		printf("\n");
 	}
 
+	printf("Policy version: %d\n\n", policydb.policyvers);
 	menu();
 	for (;;) {
 		printf("\nCommand (\'m\' for menu):  ");
-- 
2.17.2

Re: [PATCH 2/2] dismod: print policy version of loaded modules

[William Roberts]

On Wed, Apr 17, 2019 at 9:39 AM Gary Tierney <gary.tierney@fastmail.com> wrote:
>
> Signed-off-by: Gary Tierney <gary.tierney@fastmail.com>
> ---
>  checkpolicy/test/dismod.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/checkpolicy/test/dismod.c b/checkpolicy/test/dismod.c
> index d5c7eeab093a..075bd85df4e6 100644
> --- a/checkpolicy/test/dismod.c
> +++ b/checkpolicy/test/dismod.c
> @@ -903,14 +903,14 @@ int main(int argc, char **argv)
>         }
>
>         if (policydb.policy_type == POLICY_BASE) {
> -               printf("Binary base policy file loaded.\n\n");
> +               printf("Binary base policy file loaded.\n");
>         } else {
>                 printf("Binary policy module file loaded.\n");
>                 printf("Module name: %s\n", policydb.name);
>                 printf("Module version: %s\n", policydb.version);
> -               printf("\n");
>         }
>
> +       printf("Policy version: %d\n\n", policydb.policyvers);
>         menu();
>         for (;;) {
>                 printf("\nCommand (\'m\' for menu):  ");
> --
> 2.17.2
>

I don't have a problem with this, does anyone else?

Re: [Non-DoD Source] [PATCH 0/2] checkmodule: allow building modules of a specific version

[jwcart2]

On 4/17/19 12:37 PM, Gary Tierney wrote:
> These changes come from a report by a user on the Freenode IRC channel that
> they were unable to build policies for a machine that has an older version of
> libsepol installed.
> 
> A new `-c` option that mirrors checkpolicy's own has been added to checkmodule,
> and the output of a simple test is shown below:
> 
> $ cat > test.te <<EOF
> module test 1.0;
> 
> require {
>      type domain;
>      type file_type;
>      class file { read write };
> }
> 
> allow domain file_type : file { read write };
> EOF
> $ obj/usr/bin/checkmodule -m -M -c 10 -o test.mod test.te
> $ checkpolicy/test/dismod test.mod
> Reading policy...
> ... snip ...
> Binary policy module file loaded.
> Module name: test
> Module version: 1.0
> Policy version: 10
> 
> Worthy of note, however, is that these policy version numbers differ from those
> used by the kernel policy format.
> 
> Gary Tierney (2):
>    checkmodule: add support for specifying module policy version
>    dismod: print policy version of loaded modules
> 
>   checkpolicy/checkmodule.8 |  5 ++++-
>   checkpolicy/checkmodule.c | 29 +++++++++++++++++++++++++++--
>   checkpolicy/test/dismod.c |  4 ++--
>   3 files changed, 33 insertions(+), 5 deletions(-)
> 

Acked-by: James Carter <jwcart2@tycho.nsa.gov>

-- 
James Carter <jwcart2@tycho.nsa.gov>
National Security Agency

Re: [Non-DoD Source] [PATCH 0/2] checkmodule: allow building modules of a specific version

[William Roberts]

On Thu, Apr 18, 2019 at 6:27 AM jwcart2 <jwcart2@tycho.nsa.gov> wrote:
>
> On 4/17/19 12:37 PM, Gary Tierney wrote:
> > These changes come from a report by a user on the Freenode IRC channel that
> > they were unable to build policies for a machine that has an older version of
> > libsepol installed.
> >
> > A new `-c` option that mirrors checkpolicy's own has been added to checkmodule,
> > and the output of a simple test is shown below:
> >
> > $ cat > test.te <<EOF
> > module test 1.0;
> >
> > require {
> >      type domain;
> >      type file_type;
> >      class file { read write };
> > }
> >
> > allow domain file_type : file { read write };
> > EOF
> > $ obj/usr/bin/checkmodule -m -M -c 10 -o test.mod test.te
> > $ checkpolicy/test/dismod test.mod
> > Reading policy...
> > ... snip ...
> > Binary policy module file loaded.
> > Module name: test
> > Module version: 1.0
> > Policy version: 10
> >
> > Worthy of note, however, is that these policy version numbers differ from those
> > used by the kernel policy format.
> >
> > Gary Tierney (2):
> >    checkmodule: add support for specifying module policy version
> >    dismod: print policy version of loaded modules
> >
> >   checkpolicy/checkmodule.8 |  5 ++++-
> >   checkpolicy/checkmodule.c | 29 +++++++++++++++++++++++++++--
> >   checkpolicy/test/dismod.c |  4 ++--
> >   3 files changed, 33 insertions(+), 5 deletions(-)
> >
>
> Acked-by: James Carter <jwcart2@tycho.nsa.gov>

James there's a superfluous newline between strtol() and errno.

>
> --
> James Carter <jwcart2@tycho.nsa.gov>
> National Security Agency

Re: [Non-DoD Source] [PATCH 0/2] checkmodule: allow building modules of a specific version

[jwcart2]

On 4/18/19 11:18 AM, William Roberts wrote:
> On Thu, Apr 18, 2019 at 6:27 AM jwcart2 <jwcart2@tycho.nsa.gov> wrote:
>>
>> On 4/17/19 12:37 PM, Gary Tierney wrote:
>>> These changes come from a report by a user on the Freenode IRC channel that
>>> they were unable to build policies for a machine that has an older version of
>>> libsepol installed.
>>>
>>> A new `-c` option that mirrors checkpolicy's own has been added to checkmodule,
>>> and the output of a simple test is shown below:
>>>
>>> $ cat > test.te <<EOF
>>> module test 1.0;
>>>
>>> require {
>>>       type domain;
>>>       type file_type;
>>>       class file { read write };
>>> }
>>>
>>> allow domain file_type : file { read write };
>>> EOF
>>> $ obj/usr/bin/checkmodule -m -M -c 10 -o test.mod test.te
>>> $ checkpolicy/test/dismod test.mod
>>> Reading policy...
>>> ... snip ...
>>> Binary policy module file loaded.
>>> Module name: test
>>> Module version: 1.0
>>> Policy version: 10
>>>
>>> Worthy of note, however, is that these policy version numbers differ from those
>>> used by the kernel policy format.
>>>
>>> Gary Tierney (2):
>>>     checkmodule: add support for specifying module policy version
>>>     dismod: print policy version of loaded modules
>>>
>>>    checkpolicy/checkmodule.8 |  5 ++++-
>>>    checkpolicy/checkmodule.c | 29 +++++++++++++++++++++++++++--
>>>    checkpolicy/test/dismod.c |  4 ++--
>>>    3 files changed, 33 insertions(+), 5 deletions(-)
>>>
>>
>> Acked-by: James Carter <jwcart2@tycho.nsa.gov>
> 
> James there's a superfluous newline between strtol() and errno.
> 

Thanks, I missed that.

I don't see the need for another version of the patches. I can fix that minor 
issue when I merge the patches tomorrow.

>>
>> --
>> James Carter <jwcart2@tycho.nsa.gov>
>> National Security Agency
> 


-- 
James Carter <jwcart2@tycho.nsa.gov>
National Security Agency

Re: [Non-DoD Source] [PATCH 0/2] checkmodule: allow building modules of a specific version

[jwcart2]

On 4/18/19 1:49 PM, jwcart2 wrote:
> On 4/18/19 11:18 AM, William Roberts wrote:
>> On Thu, Apr 18, 2019 at 6:27 AM jwcart2 <jwcart2@tycho.nsa.gov> wrote:
>>>
>>> On 4/17/19 12:37 PM, Gary Tierney wrote:
>>>> These changes come from a report by a user on the Freenode IRC channel that
>>>> they were unable to build policies for a machine that has an older version of
>>>> libsepol installed.
>>>>
>>>> A new `-c` option that mirrors checkpolicy's own has been added to checkmodule,
>>>> and the output of a simple test is shown below:
>>>>
>>>> $ cat > test.te <<EOF
>>>> module test 1.0;
>>>>
>>>> require {
>>>>       type domain;
>>>>       type file_type;
>>>>       class file { read write };
>>>> }
>>>>
>>>> allow domain file_type : file { read write };
>>>> EOF
>>>> $ obj/usr/bin/checkmodule -m -M -c 10 -o test.mod test.te
>>>> $ checkpolicy/test/dismod test.mod
>>>> Reading policy...
>>>> ... snip ...
>>>> Binary policy module file loaded.
>>>> Module name: test
>>>> Module version: 1.0
>>>> Policy version: 10
>>>>
>>>> Worthy of note, however, is that these policy version numbers differ from those
>>>> used by the kernel policy format.
>>>>
>>>> Gary Tierney (2):
>>>>     checkmodule: add support for specifying module policy version
>>>>     dismod: print policy version of loaded modules
>>>>
>>>>    checkpolicy/checkmodule.8 |  5 ++++-
>>>>    checkpolicy/checkmodule.c | 29 +++++++++++++++++++++++++++--
>>>>    checkpolicy/test/dismod.c |  4 ++--
>>>>    3 files changed, 33 insertions(+), 5 deletions(-)
>>>>
>>>
>>> Acked-by: James Carter <jwcart2@tycho.nsa.gov>
>>
>> James there's a superfluous newline between strtol() and errno.
>>
> 
> Thanks, I missed that.
> 
> I don't see the need for another version of the patches. I can fix that minor 
> issue when I merge the patches tomorrow.
> 

Merged with the extra newline removed.

>>>
>>> -- 
>>> James Carter <jwcart2@tycho.nsa.gov>
>>> National Security Agency
>>
> 
> 


-- 
James Carter <jwcart2@tycho.nsa.gov>
National Security Agency