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* [PATCH userspace v2 0/6] Optionally rebuild policy store only if there were external changes to modules
@ 2022-02-03 16:53 Ondrej Mosnacek
  2022-02-03 16:53 ` [PATCH userspace v2 1/6] libsemanage: add missing include to boolean_record.c Ondrej Mosnacek
                   ` (5 more replies)
  0 siblings, 6 replies; 9+ messages in thread
From: Ondrej Mosnacek @ 2022-02-03 16:53 UTC (permalink / raw)
  To: selinux

This series extends libsemanage and semodule with optional capability to
detect external changes to modules and perform a rebuild if there are
any. See patch 5 for motivation and more details.

The first four patches are preparatory cleanup/refactoring, patch 5
implements the libsemanage side of the feature described above, and
patch 6 adds a command-line option to semodule that allows to turn on
the feature.

Default behavior of libsemanage and semodule is not changed (apart from
added checksum calculation on each transaction, which however seems to
add no noticeable overhead based on benchmarks - see patch 5 for
details).

Another minor difference is a slightly different format of the checksum
string printed by `semodule --checksum ...` (see patch 2).

v2:
- fix a spelling mistake found by James Carter
- eliminate 'rebuild' goto label from semanage_direct_commit()
- extract some of the semanage_direct_commit() cleanups into a separate
  patch
- unify checksum string format (semodule --checksum and the internal
  store checksum now use the same format and a common formatting helper)
  - also the semanage_module_compute_checksum() is updated to do the
    formatting rather than leaving it up to semodule
- add missing space for null terminator to the checksum string buffers
- make the semantics of check_ext_changes more natural (and make them
  actually match the documentation)
  - before: had to be used along with the rebuild flag to have an effect
    if no other changes are being done in the transaction
  - now: check_ext_changes == 1 simply forces a rebuild any time module
    content changes are detected (i.e. it's kind of a conditional
    version of -B)
  - also now: rebuild + check_ext_changes == rebuild
- rename --smart to --rebuild-if-modules-changed (it's long, but it's
  the least ambiguous I could come up with)
- also update semodule.8 man page
- update commit messages to reflect new naming and behavior

Ondrej Mosnacek (6):
  libsemanage: add missing include to boolean_record.c
  semodule,libsemanage: move module hashing into libsemanage
  libsemanage: move compressed file handling into a separate object
  libsemanage: clean up semanage_direct_commit() a bit
  libsemanage: optionally rebuild policy when modules are changed
    externally
  semodule: add command-line option to detect module changes

 libsemanage/include/semanage/handle.h         |   5 +
 libsemanage/include/semanage/modules.h        |  26 +
 libsemanage/src/boolean_record.c              |   4 +-
 libsemanage/src/compressed_file.c             | 224 ++++++++
 libsemanage/src/compressed_file.h             |  78 +++
 libsemanage/src/direct_api.c                  | 541 ++++++++----------
 libsemanage/src/direct_api.h                  |   4 -
 libsemanage/src/handle.c                      |  11 +-
 libsemanage/src/handle.h                      |   1 +
 libsemanage/src/libsemanage.map               |   5 +
 libsemanage/src/modules.c                     |  59 ++
 libsemanage/src/modules.h                     |   3 +
 libsemanage/src/semanage_store.c              |  53 +-
 libsemanage/src/semanage_store.h              |   1 +
 .../src/semanageswig_python_exception.i       |   8 +
 .../semodule => libsemanage/src}/sha256.c     |   0
 .../semodule => libsemanage/src}/sha256.h     |   0
 policycoreutils/semodule/Makefile             |   2 +-
 policycoreutils/semodule/semodule.8           |   7 +
 policycoreutils/semodule/semodule.c           |  85 ++-
 20 files changed, 721 insertions(+), 396 deletions(-)
 create mode 100644 libsemanage/src/compressed_file.c
 create mode 100644 libsemanage/src/compressed_file.h
 rename {policycoreutils/semodule => libsemanage/src}/sha256.c (100%)
 rename {policycoreutils/semodule => libsemanage/src}/sha256.h (100%)

-- 
2.34.1


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH userspace v2 1/6] libsemanage: add missing include to boolean_record.c
  2022-02-03 16:53 [PATCH userspace v2 0/6] Optionally rebuild policy store only if there were external changes to modules Ondrej Mosnacek
@ 2022-02-03 16:53 ` Ondrej Mosnacek
  2022-02-11 21:51   ` James Carter
  2022-02-03 16:53 ` [PATCH userspace v2 2/6] semodule,libsemanage: move module hashing into libsemanage Ondrej Mosnacek
                   ` (4 subsequent siblings)
  5 siblings, 1 reply; 9+ messages in thread
From: Ondrej Mosnacek @ 2022-02-03 16:53 UTC (permalink / raw)
  To: selinux

It uses asprintf(3), but doesn't directly include <stdio.h> - fix it.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
---
 libsemanage/src/boolean_record.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/libsemanage/src/boolean_record.c b/libsemanage/src/boolean_record.c
index 95f3a862..40dc6545 100644
--- a/libsemanage/src/boolean_record.c
+++ b/libsemanage/src/boolean_record.c
@@ -7,6 +7,9 @@
  */
 
 #include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+
 #include <sepol/boolean_record.h>
 
 typedef sepol_bool_t semanage_bool_t;
@@ -20,7 +23,6 @@ typedef semanage_bool_key_t record_key_t;
 #include "boolean_internal.h"
 #include "handle.h"
 #include "database.h"
-#include <stdlib.h>
 #include <selinux/selinux.h>
 
 /* Key */
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH userspace v2 2/6] semodule,libsemanage: move module hashing into libsemanage
  2022-02-03 16:53 [PATCH userspace v2 0/6] Optionally rebuild policy store only if there were external changes to modules Ondrej Mosnacek
  2022-02-03 16:53 ` [PATCH userspace v2 1/6] libsemanage: add missing include to boolean_record.c Ondrej Mosnacek
@ 2022-02-03 16:53 ` Ondrej Mosnacek
  2022-02-03 16:53 ` [PATCH userspace v2 3/6] libsemanage: move compressed file handling into a separate object Ondrej Mosnacek
                   ` (3 subsequent siblings)
  5 siblings, 0 replies; 9+ messages in thread
From: Ondrej Mosnacek @ 2022-02-03 16:53 UTC (permalink / raw)
  To: selinux

The main goal of this move is to have the SHA-256 implementation under
libsemanage, since upcoming patches will make use of SHA-256 for a
different (but similar) purpose in libsemanage. Having the hashing code
in libsemanage will reduce code duplication and allow for easier hash
algorithm upgrade in the future.

Note that libselinux currently also contains a hash function
implementation (for yet another different purpose). This patch doesn't
make any effort to address that duplicity yet.

This patch also changes the format of the hash string printed by
semodule to include the name of the hash. The intent is to avoid
ambiguity and potential collisions when the algorithm is potentially
changed in the future.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
---
 libsemanage/include/semanage/modules.h        | 26 ++++++++
 libsemanage/src/libsemanage.map               |  4 ++
 libsemanage/src/modules.c                     | 59 +++++++++++++++++++
 .../src/semanageswig_python_exception.i       |  8 +++
 .../semodule => libsemanage/src}/sha256.c     |  0
 .../semodule => libsemanage/src}/sha256.h     |  0
 policycoreutils/semodule/Makefile             |  2 +-
 policycoreutils/semodule/semodule.c           | 53 +++++------------
 8 files changed, 114 insertions(+), 38 deletions(-)
 rename {policycoreutils/semodule => libsemanage/src}/sha256.c (100%)
 rename {policycoreutils/semodule => libsemanage/src}/sha256.h (100%)

diff --git a/libsemanage/include/semanage/modules.h b/libsemanage/include/semanage/modules.h
index b51f61f0..14666f6d 100644
--- a/libsemanage/include/semanage/modules.h
+++ b/libsemanage/include/semanage/modules.h
@@ -282,4 +282,30 @@ extern int semanage_module_get_enabled(semanage_handle_t *sh,
 				       const semanage_module_key_t *modkey,
 				       int *enabled);
 
+/* Compute checksum for @modkey module contents.
+ *
+ * If @checksum is NULL, the function will just return the length of the
+ * checksum string in @checksum_len (checksum strings are guaranteed to
+ * have a fixed length for a given libsemanage binary). @modkey and @cil
+ * are ignored in this case and should be set to NULL and 0 (respectively).
+ *
+ * If @checksum is non-NULL, on success, @checksum will point to a buffer
+ * containing the checksum string and @checksum_len will point to the
+ * length of the string (without the null terminator). The semantics of
+ * @cil are the same as for @extract_cil in semanage_module_extract().
+ *
+ * The caller is responsible to free the buffer returned in @checksum (using
+ * free(3)).
+ *
+ * Callers may assume that if the checksum strings for two modules match,
+ * the module content is the same (collisions are theoretically possible,
+ * yet extremely unlikely).
+ *
+ * Returns 0 on success and -1 on error.
+ */
+extern int semanage_module_compute_checksum(semanage_handle_t *sh,
+					    semanage_module_key_t *modkey,
+					    int cil, char **checksum,
+					    size_t *checksum_len);
+
 #endif
diff --git a/libsemanage/src/libsemanage.map b/libsemanage/src/libsemanage.map
index 3ea7b60f..00259fc8 100644
--- a/libsemanage/src/libsemanage.map
+++ b/libsemanage/src/libsemanage.map
@@ -345,3 +345,7 @@ LIBSEMANAGE_1.1 {
     semanage_module_remove_key;
     semanage_set_store_root;
 } LIBSEMANAGE_1.0;
+
+LIBSEMANAGE_3.4 {
+    semanage_module_compute_checksum;
+} LIBSEMANAGE_1.1;
diff --git a/libsemanage/src/modules.c b/libsemanage/src/modules.c
index c98df4dd..fe937519 100644
--- a/libsemanage/src/modules.c
+++ b/libsemanage/src/modules.c
@@ -35,11 +35,13 @@
 #include <fcntl.h>
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <sys/mman.h>
 #include <errno.h>
 #include <ctype.h>
 
 #include "handle.h"
 #include "modules.h"
+#include "sha256.h"
 #include "debug.h"
 
 int semanage_module_install(semanage_handle_t * sh,
@@ -976,3 +978,60 @@ int semanage_module_remove_key(semanage_handle_t *sh,
 	return sh->funcs->remove_key(sh, modkey);
 }
 
+static const char CHECKSUM_TYPE[] = "sha256";
+static const size_t CHECKSUM_CONTENT_SIZE = sizeof(CHECKSUM_TYPE) + 1 + 2 * SHA256_HASH_SIZE;
+
+static void semanage_hash_to_checksum_string(const uint8_t *hash, char *checksum)
+{
+	size_t i;
+
+	checksum += sprintf(checksum, "%s:", CHECKSUM_TYPE);
+	for (i = 0; i < SHA256_HASH_SIZE; i++) {
+		checksum += sprintf(checksum, "%02x", (unsigned)hash[i]);
+	}
+}
+
+int semanage_module_compute_checksum(semanage_handle_t *sh,
+				     semanage_module_key_t *modkey,
+				     int cil, char **checksum,
+				     size_t *checksum_len)
+{
+	semanage_module_info_t *extract_info = NULL;
+	Sha256Context context;
+	SHA256_HASH sha256_hash;
+	char *checksum_str;
+	void *data;
+	size_t data_len = 0;
+	int result;
+
+	if (!checksum_len)
+		return -1;
+
+	if (!checksum) {
+		*checksum_len = CHECKSUM_CONTENT_SIZE;
+		return 0;
+	}
+
+	result = semanage_module_extract(sh, modkey, cil, &data, &data_len, &extract_info);
+	if (result != 0)
+		return -1;
+
+	semanage_module_info_destroy(sh, extract_info);
+	free(extract_info);
+
+	Sha256Initialise(&context);
+	Sha256Update(&context, data, data_len);
+	Sha256Finalise(&context, &sha256_hash);
+
+	munmap(data, data_len);
+
+	checksum_str = malloc(CHECKSUM_CONTENT_SIZE + 1 /* '\0' */);
+	if (!checksum_str)
+		return -1;
+
+	semanage_hash_to_checksum_string(sha256_hash.bytes, checksum_str);
+
+	*checksum = checksum_str;
+	*checksum_len = CHECKSUM_CONTENT_SIZE;
+	return 0;
+}
diff --git a/libsemanage/src/semanageswig_python_exception.i b/libsemanage/src/semanageswig_python_exception.i
index 372ec948..0df8bbc3 100644
--- a/libsemanage/src/semanageswig_python_exception.i
+++ b/libsemanage/src/semanageswig_python_exception.i
@@ -351,6 +351,14 @@
   }
 }
 
+%exception semanage_module_compute_checksum {
+  $action
+  if (result < 0) {
+     PyErr_SetFromErrno(PyExc_OSError);
+     SWIG_fail;
+  }
+}
+
 %exception semanage_msg_get_level {
   $action
   if (result < 0) {
diff --git a/policycoreutils/semodule/sha256.c b/libsemanage/src/sha256.c
similarity index 100%
rename from policycoreutils/semodule/sha256.c
rename to libsemanage/src/sha256.c
diff --git a/policycoreutils/semodule/sha256.h b/libsemanage/src/sha256.h
similarity index 100%
rename from policycoreutils/semodule/sha256.h
rename to libsemanage/src/sha256.h
diff --git a/policycoreutils/semodule/Makefile b/policycoreutils/semodule/Makefile
index 9875ac38..73801e48 100644
--- a/policycoreutils/semodule/Makefile
+++ b/policycoreutils/semodule/Makefile
@@ -6,7 +6,7 @@ MANDIR = $(PREFIX)/share/man
 
 CFLAGS ?= -Werror -Wall -W
 override LDLIBS += -lsepol -lselinux -lsemanage
-SEMODULE_OBJS = semodule.o sha256.o
+SEMODULE_OBJS = semodule.o
 
 all: semodule genhomedircon
 
diff --git a/policycoreutils/semodule/semodule.c b/policycoreutils/semodule/semodule.c
index 94a9d131..f4a76289 100644
--- a/policycoreutils/semodule/semodule.c
+++ b/policycoreutils/semodule/semodule.c
@@ -25,8 +25,6 @@
 #include <sepol/cil/cil.h>
 #include <semanage/modules.h>
 
-#include "sha256.h"
-
 enum client_modes {
 	NO_MODE, INSTALL_M, REMOVE_M, EXTRACT_M, CIL_M, HLL_M,
 	LIST_M, RELOAD, PRIORITY_M, ENABLE_M, DISABLE_M
@@ -348,60 +346,38 @@ static void parse_command_line(int argc, char **argv)
 
 /* Get module checksum */
 static char *hash_module_data(const char *module_name, const int prio) {
-	semanage_module_info_t *extract_info = NULL;
 	semanage_module_key_t *modkey = NULL;
-	Sha256Context context;
-	uint8_t sha256_hash[SHA256_HASH_SIZE];
-	char *sha256_buf = NULL;
-	void *data;
-	size_t data_len = 0, i;
+	char *hash_str = NULL;
+	void *hash = NULL;
+	size_t hash_len = 0;
 	int result;
 
 	result = semanage_module_key_create(sh, &modkey);
 	if (result != 0) {
-		goto cleanup_extract;
+		goto cleanup;
 	}
 
 	result = semanage_module_key_set_name(sh, modkey, module_name);
 	if (result != 0) {
-		goto cleanup_extract;
+		goto cleanup;
 	}
 
 	result = semanage_module_key_set_priority(sh, modkey, prio);
 	if (result != 0) {
-		goto cleanup_extract;
+		goto cleanup;
 	}
 
-	result = semanage_module_extract(sh, modkey, 1, &data, &data_len,
-									 &extract_info);
+	result = semanage_module_compute_checksum(sh, modkey, 1, &hash_str,
+						  &hash_len);
 	if (result != 0) {
-		goto cleanup_extract;
-	}
-
-	Sha256Initialise(&context);
-	Sha256Update(&context, data, data_len);
-
-	Sha256Finalise(&context, (SHA256_HASH *)sha256_hash);
-
-	sha256_buf = calloc(1, SHA256_HASH_SIZE * 2 + 1);
-
-	if (sha256_buf == NULL)
-		goto cleanup_extract;
-
-	for (i = 0; i < SHA256_HASH_SIZE; i++) {
-		sprintf((&sha256_buf[i * 2]), "%02x", sha256_hash[i]);
+		goto cleanup;
 	}
-	sha256_buf[i * 2] = 0;
 
-cleanup_extract:
-	if (data_len > 0) {
-		munmap(data, data_len);
-	}
-	semanage_module_info_destroy(sh, extract_info);
-	free(extract_info);
+cleanup:
+	free(hash);
 	semanage_module_key_destroy(sh, modkey);
 	free(modkey);
-	return sha256_buf;
+	return hash_str;
 }
 
 int main(int argc, char *argv[])
@@ -669,7 +645,10 @@ cleanup_extract:
 					/* fixed width columns */
 					column[0] = sizeof("000") - 1;
 					column[3] = sizeof("disabled") - 1;
-					column[4] = 64; /* SHA256_HASH_SIZE * 2 */
+
+					result = semanage_module_compute_checksum(sh, NULL, 0, NULL,
+										  &column[4]);
+					if (result != 0) goto cleanup_list;
 
 					/* variable width columns */
 					const char *tmp = NULL;
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH userspace v2 3/6] libsemanage: move compressed file handling into a separate object
  2022-02-03 16:53 [PATCH userspace v2 0/6] Optionally rebuild policy store only if there were external changes to modules Ondrej Mosnacek
  2022-02-03 16:53 ` [PATCH userspace v2 1/6] libsemanage: add missing include to boolean_record.c Ondrej Mosnacek
  2022-02-03 16:53 ` [PATCH userspace v2 2/6] semodule,libsemanage: move module hashing into libsemanage Ondrej Mosnacek
@ 2022-02-03 16:53 ` Ondrej Mosnacek
  2022-02-03 16:53 ` [PATCH userspace v2 4/6] libsemanage: clean up semanage_direct_commit() a bit Ondrej Mosnacek
                   ` (2 subsequent siblings)
  5 siblings, 0 replies; 9+ messages in thread
From: Ondrej Mosnacek @ 2022-02-03 16:53 UTC (permalink / raw)
  To: selinux

In order to reduce exisiting and future code duplication and to avoid
some unnecessary allocations and copying, factor the compressed file
utility functions out into a separate C/header file and refactor their
interface.

Note that this change effectively removes the __fsetlocking(3) call from
semanage_load_files() - I haven't been able to figure out what purpose
it serves, but it seems pointless...

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
---
 libsemanage/src/compressed_file.c | 224 +++++++++++++++++++++++++
 libsemanage/src/compressed_file.h |  78 +++++++++
 libsemanage/src/direct_api.c      | 263 +++++-------------------------
 libsemanage/src/direct_api.h      |   4 -
 libsemanage/src/semanage_store.c  |  52 ++----
 5 files changed, 354 insertions(+), 267 deletions(-)
 create mode 100644 libsemanage/src/compressed_file.c
 create mode 100644 libsemanage/src/compressed_file.h

diff --git a/libsemanage/src/compressed_file.c b/libsemanage/src/compressed_file.c
new file mode 100644
index 00000000..5546b830
--- /dev/null
+++ b/libsemanage/src/compressed_file.c
@@ -0,0 +1,224 @@
+/* Author: Jason Tang	  <jtang@tresys.com>
+ *         Christopher Ashworth <cashworth@tresys.com>
+ *         Ondrej Mosnacek <omosnacek@gmail.com>
+ *
+ * Copyright (C) 2004-2006 Tresys Technology, LLC
+ * Copyright (C) 2005-2021 Red Hat, Inc.
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2.1 of the License, or (at your option) any later version.
+ *
+ *  This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public
+ *  License along with this library; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+
+#include <unistd.h>
+#include <fcntl.h>
+
+#include <bzlib.h>
+
+#include "compressed_file.h"
+
+#include "debug.h"
+
+#define BZ2_MAGICSTR "BZh"
+#define BZ2_MAGICLEN (sizeof(BZ2_MAGICSTR)-1)
+
+/* bzip() a data to a file, returning the total number of compressed bytes
+ * in the file.  Returns -1 if file could not be compressed. */
+static int bzip(semanage_handle_t *sh, const char *filename, void *data,
+		size_t num_bytes)
+{
+	BZFILE* b;
+	size_t  size = 1<<16;
+	int     bzerror;
+	size_t  total = 0;
+	size_t len = 0;
+	FILE *f;
+
+	if ((f = fopen(filename, "wb")) == NULL) {
+		return -1;
+	}
+
+	if (!sh->conf->bzip_blocksize) {
+		if (fwrite(data, 1, num_bytes, f) < num_bytes) {
+			fclose(f);
+			return -1;
+		}
+		fclose(f);
+		return 0;
+	}
+
+	b = BZ2_bzWriteOpen( &bzerror, f, sh->conf->bzip_blocksize, 0, 0);
+	if (bzerror != BZ_OK) {
+		BZ2_bzWriteClose ( &bzerror, b, 1, 0, 0 );
+		fclose(f);
+		return -1;
+	}
+
+	while ( num_bytes > total ) {
+		if (num_bytes - total > size) {
+			len = size;
+		} else {
+			len = num_bytes - total;
+		}
+		BZ2_bzWrite ( &bzerror, b, (uint8_t *)data + total, len );
+		if (bzerror == BZ_IO_ERROR) {
+			BZ2_bzWriteClose ( &bzerror, b, 1, 0, 0 );
+			fclose(f);
+			return -1;
+		}
+		total += len;
+	}
+
+	BZ2_bzWriteClose ( &bzerror, b, 0, 0, 0 );
+	fclose(f);
+	if (bzerror == BZ_IO_ERROR) {
+		return -1;
+	}
+	return 0;
+}
+
+/* bunzip() a file to '*data', returning the total number of uncompressed bytes
+ * in the file.  Returns -1 if file could not be decompressed. */
+static ssize_t bunzip(semanage_handle_t *sh, FILE *f, void **data)
+{
+	BZFILE*  b = NULL;
+	size_t   nBuf;
+	uint8_t* buf = NULL;
+	size_t   size = 1<<18;
+	size_t   bufsize = size;
+	int      bzerror;
+	size_t   total = 0;
+	uint8_t* uncompress = NULL;
+	uint8_t* tmpalloc = NULL;
+	int      ret = -1;
+
+	buf = malloc(bufsize);
+	if (buf == NULL) {
+		ERR(sh, "Failure allocating memory.");
+		goto exit;
+	}
+
+	/* Check if the file is bzipped */
+	bzerror = fread(buf, 1, BZ2_MAGICLEN, f);
+	rewind(f);
+	if ((bzerror != BZ2_MAGICLEN) || memcmp(buf, BZ2_MAGICSTR, BZ2_MAGICLEN)) {
+		goto exit;
+	}
+
+	b = BZ2_bzReadOpen ( &bzerror, f, 0, sh->conf->bzip_small, NULL, 0 );
+	if ( bzerror != BZ_OK ) {
+		ERR(sh, "Failure opening bz2 archive.");
+		goto exit;
+	}
+
+	uncompress = malloc(size);
+	if (uncompress == NULL) {
+		ERR(sh, "Failure allocating memory.");
+		goto exit;
+	}
+
+	while ( bzerror == BZ_OK) {
+		nBuf = BZ2_bzRead ( &bzerror, b, buf, bufsize);
+		if (( bzerror == BZ_OK ) || ( bzerror == BZ_STREAM_END )) {
+			if (total + nBuf > size) {
+				size *= 2;
+				tmpalloc = realloc(uncompress, size);
+				if (tmpalloc == NULL) {
+					ERR(sh, "Failure allocating memory.");
+					goto exit;
+				}
+				uncompress = tmpalloc;
+			}
+			memcpy(&uncompress[total], buf, nBuf);
+			total += nBuf;
+		}
+	}
+	if ( bzerror != BZ_STREAM_END ) {
+		ERR(sh, "Failure reading bz2 archive.");
+		goto exit;
+	}
+
+	ret = total;
+	*data = uncompress;
+
+exit:
+	BZ2_bzReadClose ( &bzerror, b );
+	free(buf);
+	if ( ret < 0 ) {
+		free(uncompress);
+	}
+	return ret;
+}
+
+int map_compressed_file(semanage_handle_t *sh, const char *path,
+			struct file_contents *contents)
+{
+	ssize_t size = -1;
+	void *uncompress;
+	int ret = 0, fd = -1;
+	FILE *file = NULL;
+
+	fd = open(path, O_RDONLY);
+	if (fd == -1) {
+		ERR(sh, "Unable to open %s\n", path);
+		return -1;
+	}
+
+	file = fdopen(fd, "r");
+	if (file == NULL) {
+		ERR(sh, "Unable to open %s\n", path);
+		close(fd);
+		return -1;
+	}
+
+	if ((size = bunzip(sh, file, &uncompress)) >= 0) {
+		contents->data = uncompress;
+		contents->len = size;
+		contents->compressed = 1;
+	} else {
+		struct stat sb;
+		if (fstat(fd, &sb) == -1 ||
+		    (uncompress = mmap(NULL, sb.st_size, PROT_READ, MAP_PRIVATE, fd, 0)) ==
+		    MAP_FAILED) {
+			ret = -1;
+		} else {
+			contents->data = uncompress;
+			contents->len = sb.st_size;
+			contents->compressed = 0;
+		}
+	}
+	fclose(file);
+	return ret;
+}
+
+void unmap_compressed_file(struct file_contents *contents)
+{
+	if (!contents->data)
+		return;
+
+	if (contents->compressed) {
+		free(contents->data);
+	} else {
+		munmap(contents->data, contents->len);
+	}
+}
+
+int write_compressed_file(semanage_handle_t *sh, const char *path,
+			  void *data, size_t len)
+{
+	return bzip(sh, path, data, len);
+}
diff --git a/libsemanage/src/compressed_file.h b/libsemanage/src/compressed_file.h
new file mode 100644
index 00000000..96cfb4b6
--- /dev/null
+++ b/libsemanage/src/compressed_file.h
@@ -0,0 +1,78 @@
+/* Author: Jason Tang	  <jtang@tresys.com>
+ *         Christopher Ashworth <cashworth@tresys.com>
+ *         Ondrej Mosnacek <omosnacek@gmail.com>
+ *
+ * Copyright (C) 2004-2006 Tresys Technology, LLC
+ * Copyright (C) 2005-2021 Red Hat, Inc.
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2.1 of the License, or (at your option) any later version.
+ *
+ *  This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public
+ *  License along with this library; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#ifndef _SEMANAGE_CIL_FILE_H_
+#define _SEMANAGE_CIL_FILE_H_
+
+#include <sys/mman.h>
+#include <sys/types.h>
+
+#include "handle.h"
+
+struct file_contents {
+	void *data; /** file contents (uncompressed) */
+	size_t len; /** length of contents */
+	int compressed; /** whether file was compressed */
+};
+
+/**
+ * Map/read a possibly-compressed file into memory.
+ *
+ * If the file is bzip compressed map_file will uncompress the file into
+ * @p contents. The caller is responsible for calling
+ * @ref unmap_compressed_file on @p contents on success.
+ *
+ * @param sh        semanage handle
+ * @param path      path to the file
+ * @param contents  pointer to struct file_contents, which will be
+ *   populated with data pointer, size, and an indication whether
+ *   the file was compressed or not
+ *
+ * @return 0 on success, -1 otherwise.
+ */
+int map_compressed_file(semanage_handle_t *sh, const char *path,
+			struct file_contents *contents);
+
+/**
+ * Destroy a previously mapped possibly-compressed file.
+ *
+ * If all fields of @p contents are zero/NULL, the function is
+ * guaranteed to do nothing.
+ *
+ * @param contents  pointer to struct file_contents to destroy
+ */
+void unmap_compressed_file(struct file_contents *contents);
+
+/**
+ * Write bytes into a file, using compression if configured.
+ *
+ * @param sh    semanage handle
+ * @param path  path to the file
+ * @param data  pointer to the data
+ * @param len   length of the data
+ *
+ * @return 0 on success, -1 otherwise.
+ */
+int write_compressed_file(semanage_handle_t *sh, const char *path,
+			  void *data, size_t len);
+
+#endif
diff --git a/libsemanage/src/direct_api.c b/libsemanage/src/direct_api.c
index f0e2300a..7eb6938b 100644
--- a/libsemanage/src/direct_api.c
+++ b/libsemanage/src/direct_api.c
@@ -50,6 +50,7 @@
 
 #include "debug.h"
 #include "handle.h"
+#include "compressed_file.h"
 #include "modules.h"
 #include "direct_api.h"
 #include "semanage_store.h"
@@ -446,194 +447,6 @@ static int parse_module_headers(semanage_handle_t * sh, char *module_data,
        return 0;
 }
 
-#include <stdlib.h>
-#include <bzlib.h>
-#include <string.h>
-#include <sys/sendfile.h>
-
-/* bzip() a data to a file, returning the total number of compressed bytes
- * in the file.  Returns -1 if file could not be compressed. */
-static ssize_t bzip(semanage_handle_t *sh, const char *filename, char *data,
-			size_t num_bytes)
-{
-	BZFILE* b;
-	size_t  size = 1<<16;
-	int     bzerror;
-	size_t  total = 0;
-	size_t len = 0;
-	FILE *f;
-
-	if ((f = fopen(filename, "wb")) == NULL) {
-		return -1;
-	}
-
-	if (!sh->conf->bzip_blocksize) {
-		if (fwrite(data, 1, num_bytes, f) < num_bytes) {
-			fclose(f);
-			return -1;
-		}
-		fclose(f);
-		return num_bytes;
-	}
-
-	b = BZ2_bzWriteOpen( &bzerror, f, sh->conf->bzip_blocksize, 0, 0);
-	if (bzerror != BZ_OK) {
-		BZ2_bzWriteClose ( &bzerror, b, 1, 0, 0 );
-		return -1;
-	}
-	
-	while ( num_bytes > total ) {
-		if (num_bytes - total > size) {
-			len = size;
-		} else {
-			len = num_bytes - total;
-		}
-		BZ2_bzWrite ( &bzerror, b, &data[total], len );
-		if (bzerror == BZ_IO_ERROR) { 
-			BZ2_bzWriteClose ( &bzerror, b, 1, 0, 0 );
-			return -1;
-		}
-		total += len;
-	}
-
-	BZ2_bzWriteClose ( &bzerror, b, 0, 0, 0 );
-	fclose(f);
-	if (bzerror == BZ_IO_ERROR) {
-		return -1;
-	}
-	return total;
-}
-
-#define BZ2_MAGICSTR "BZh"
-#define BZ2_MAGICLEN (sizeof(BZ2_MAGICSTR)-1)
-
-/* bunzip() a file to '*data', returning the total number of uncompressed bytes
- * in the file.  Returns -1 if file could not be decompressed. */
-ssize_t bunzip(semanage_handle_t *sh, FILE *f, char **data)
-{
-	BZFILE* b = NULL;
-	size_t  nBuf;
-	char*   buf = NULL;
-	size_t  size = 1<<18;
-	size_t  bufsize = size;
-	int     bzerror;
-	size_t  total = 0;
-	char*   uncompress = NULL;
-	char*   tmpalloc = NULL;
-	int     ret = -1;
-
-	buf = malloc(bufsize);
-	if (buf == NULL) {
-		ERR(sh, "Failure allocating memory.");
-		goto exit;
-	}
-
-	/* Check if the file is bzipped */
-	bzerror = fread(buf, 1, BZ2_MAGICLEN, f);
-	rewind(f);
-	if ((bzerror != BZ2_MAGICLEN) || memcmp(buf, BZ2_MAGICSTR, BZ2_MAGICLEN)) {
-		goto exit;
-	}
-
-	b = BZ2_bzReadOpen ( &bzerror, f, 0, sh->conf->bzip_small, NULL, 0 );
-	if ( bzerror != BZ_OK ) {
-		ERR(sh, "Failure opening bz2 archive.");
-		goto exit;
-	}
-
-	uncompress = malloc(size);
-	if (uncompress == NULL) {
-		ERR(sh, "Failure allocating memory.");
-		goto exit;
-	}
-
-	while ( bzerror == BZ_OK) {
-		nBuf = BZ2_bzRead ( &bzerror, b, buf, bufsize);
-		if (( bzerror == BZ_OK ) || ( bzerror == BZ_STREAM_END )) {
-			if (total + nBuf > size) {
-				size *= 2;
-				tmpalloc = realloc(uncompress, size);
-				if (tmpalloc == NULL) {
-					ERR(sh, "Failure allocating memory.");
-					goto exit;
-				}
-				uncompress = tmpalloc;
-			}
-			memcpy(&uncompress[total], buf, nBuf);
-			total += nBuf;
-		}
-	}
-	if ( bzerror != BZ_STREAM_END ) {
-		ERR(sh, "Failure reading bz2 archive.");
-		goto exit;
-	}
-
-	ret = total;
-	*data = uncompress;
-
-exit:
-	BZ2_bzReadClose ( &bzerror, b );
-	free(buf);
-	if ( ret < 0 ) {
-		free(uncompress);
-	}
-	return ret;
-}
-
-/* mmap() a file to '*data',
- *  If the file is bzip compressed map_file will uncompress 
- * the file into '*data'.
- * Returns the total number of bytes in memory .
- * Returns -1 if file could not be opened or mapped. */
-static ssize_t map_file(semanage_handle_t *sh, const char *path, char **data,
-			int *compressed)
-{
-	ssize_t size = -1;
-	char *uncompress;
-	int fd = -1;
-	FILE *file = NULL;
-
-	fd = open(path, O_RDONLY);
-	if (fd == -1) {
-		ERR(sh, "Unable to open %s\n", path);
-		return -1;
-	}
-
-	file = fdopen(fd, "r");
-	if (file == NULL) {
-		ERR(sh, "Unable to open %s\n", path);
-		close(fd);
-		return -1;
-	}
-
-	if ((size = bunzip(sh, file, &uncompress)) > 0) {
-		*data = mmap(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
-		if (*data == MAP_FAILED) {
-			free(uncompress);
-			fclose(file);
-			return -1;
-		} else {
-			memcpy(*data, uncompress, size);
-		}
-		free(uncompress);
-		*compressed = 1;
-	} else {
-		struct stat sb;
-		if (fstat(fd, &sb) == -1 ||
-		    (*data = mmap(NULL, sb.st_size, PROT_READ, MAP_PRIVATE, fd, 0)) ==
-		    MAP_FAILED) {
-			size = -1;
-		} else {
-			size = sb.st_size;
-		}
-		*compressed = 0;
-	} 
-
-	fclose(file);
-
-	return size;
-}
-
 /* Writes a block of data to a file.  Returns 0 on success, -1 on
  * error. */
 static int write_file(semanage_handle_t * sh,
@@ -1045,15 +858,12 @@ static int semanage_compile_module(semanage_handle_t *sh,
 	char *compiler_path = NULL;
 	char *cil_data = NULL;
 	char *err_data = NULL;
-	char *hll_data = NULL;
 	char *start = NULL;
 	char *end = NULL;
-	ssize_t hll_data_len = 0;
-	ssize_t bzip_status;
 	int status = 0;
-	int compressed;
 	size_t cil_data_len = 0;
 	size_t err_data_len = 0;
+	struct file_contents hll_contents = {};
 
 	if (!strcasecmp(modinfo->lang_ext, "cil")) {
 		goto cleanup;
@@ -1084,13 +894,15 @@ static int semanage_compile_module(semanage_handle_t *sh,
 		goto cleanup;
 	}
 
-	if ((hll_data_len = map_file(sh, hll_path, &hll_data, &compressed)) <= 0) {
+	status = map_compressed_file(sh, hll_path, &hll_contents);
+	if (status < 0) {
 		ERR(sh, "Unable to read file %s\n", hll_path);
-		status = -1;
 		goto cleanup;
 	}
 
-	status = semanage_pipe_data(sh, compiler_path, hll_data, (size_t)hll_data_len, &cil_data, &cil_data_len, &err_data, &err_data_len);
+	status = semanage_pipe_data(sh, compiler_path, hll_contents.data,
+				    hll_contents.len, &cil_data, &cil_data_len,
+				    &err_data, &err_data_len);
 	if (err_data_len > 0) {
 		for (start = end = err_data; end < err_data + err_data_len; end++) {
 			if (*end == '\n') {
@@ -1110,10 +922,9 @@ static int semanage_compile_module(semanage_handle_t *sh,
 		goto cleanup;
 	}
 
-	bzip_status = bzip(sh, cil_path, cil_data, cil_data_len);
-	if (bzip_status == -1) {
-		ERR(sh, "Failed to bzip %s\n", cil_path);
-		status = -1;
+	status = write_compressed_file(sh, cil_path, cil_data, cil_data_len);
+	if (status == -1) {
+		ERR(sh, "Failed to write %s\n", cil_path);
 		goto cleanup;
 	}
 
@@ -1131,9 +942,7 @@ static int semanage_compile_module(semanage_handle_t *sh,
 	}
 
 cleanup:
-	if (hll_data_len > 0) {
-		munmap(hll_data, hll_data_len);
-	}
+	unmap_compressed_file(&hll_contents);
 	free(cil_data);
 	free(err_data);
 	free(compiler_path);
@@ -1756,19 +1565,17 @@ static int semanage_direct_install_file(semanage_handle_t * sh,
 {
 
 	int retval = -1;
-	char *data = NULL;
-	ssize_t data_len = 0;
-	int compressed = 0;
 	char *path = NULL;
 	char *filename;
 	char *lang_ext = NULL;
 	char *module_name = NULL;
 	char *separator;
 	char *version = NULL;
+	struct file_contents contents = {};
 
-	if ((data_len = map_file(sh, install_filename, &data, &compressed)) <= 0) {
+	retval = map_compressed_file(sh, install_filename, &contents);
+	if (retval < 0) {
 		ERR(sh, "Unable to read file %s\n", install_filename);
-		retval = -1;
 		goto cleanup;
 	}
 
@@ -1781,7 +1588,7 @@ static int semanage_direct_install_file(semanage_handle_t * sh,
 
 	filename = basename(path);
 
-	if (compressed) {
+	if (contents.compressed) {
 		separator = strrchr(filename, '.');
 		if (separator == NULL) {
 			ERR(sh, "Compressed module does not have a valid extension.");
@@ -1805,7 +1612,8 @@ static int semanage_direct_install_file(semanage_handle_t * sh,
 	}
 
 	if (strcmp(lang_ext, "pp") == 0) {
-		retval = parse_module_headers(sh, data, data_len, &module_name, &version);
+		retval = parse_module_headers(sh, contents.data, contents.len,
+					      &module_name, &version);
 		free(version);
 		if (retval != 0)
 			goto cleanup;
@@ -1822,10 +1630,11 @@ static int semanage_direct_install_file(semanage_handle_t * sh,
 		fprintf(stderr, "Warning: SELinux userspace will refer to the module from %s as %s rather than %s\n", install_filename, module_name, filename);
 	}
 
-	retval = semanage_direct_install(sh, data, data_len, module_name, lang_ext);
+	retval = semanage_direct_install(sh, contents.data, contents.len,
+					 module_name, lang_ext);
 
 cleanup:
-	if (data_len > 0) munmap(data, data_len);
+	unmap_compressed_file(&contents);
 	free(module_name);
 	free(path);
 
@@ -1844,10 +1653,8 @@ static int semanage_direct_extract(semanage_handle_t * sh,
 	enum semanage_module_path_type file_type;
 	int rc = -1;
 	semanage_module_info_t *_modinfo = NULL;
-	ssize_t _data_len;
-	char *_data;
-	int compressed;
 	struct stat sb;
+	struct file_contents contents = {};
 
 	/* get path of module */
 	rc = semanage_module_get_path(
@@ -1903,19 +1710,33 @@ static int semanage_direct_extract(semanage_handle_t * sh,
 		}
 	}
 
-	_data_len = map_file(sh, input_file, &_data, &compressed);
-	if (_data_len <= 0) {
+	rc = map_compressed_file(sh, input_file, &contents);
+	if (rc < 0) {
 		ERR(sh, "Error mapping file: %s", input_file);
-		rc = -1;
 		goto cleanup;
 	}
 
+	/* The API promises an mmap'ed pointer */
+	if (contents.compressed) {
+		*mapped_data = mmap(NULL, contents.len, PROT_READ|PROT_WRITE,
+				    MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
+		if (*mapped_data == MAP_FAILED) {
+			ERR(sh, "Unable to map memory");
+			rc = -1;
+			goto cleanup;
+		}
+		memcpy(*mapped_data, contents.data, contents.len);
+		free(contents.data);
+	} else {
+		*mapped_data = contents.data;
+	}
+
 	*modinfo = _modinfo;
-	*data_len = (size_t)_data_len;
-	*mapped_data = _data;
+	*data_len = contents.len;
 
 cleanup:
 	if (rc != 0) {
+		unmap_compressed_file(&contents);
 		semanage_module_info_destroy(sh, _modinfo);
 		free(_modinfo);
 	}
@@ -2869,8 +2690,8 @@ static int semanage_direct_install_info(semanage_handle_t *sh,
 		goto cleanup;
 	}
 
-	ret = bzip(sh, path, data, data_len);
-	if (ret <= 0) {
+	ret = write_compressed_file(sh, path, data, data_len);
+	if (ret < 0) {
 		ERR(sh, "Error while writing to %s.", path);
 		status = -3;
 		goto cleanup;
diff --git a/libsemanage/src/direct_api.h b/libsemanage/src/direct_api.h
index e56107b2..ffd428eb 100644
--- a/libsemanage/src/direct_api.h
+++ b/libsemanage/src/direct_api.h
@@ -39,8 +39,4 @@ int semanage_direct_access_check(struct semanage_handle *sh);
 
 int semanage_direct_mls_enabled(struct semanage_handle *sh);
 
-#include <stdio.h>
-#include <unistd.h>
-ssize_t bunzip(struct semanage_handle *sh, FILE *f, char **data);
-
 #endif
diff --git a/libsemanage/src/semanage_store.c b/libsemanage/src/semanage_store.c
index c6a736fe..633ee731 100644
--- a/libsemanage/src/semanage_store.c
+++ b/libsemanage/src/semanage_store.c
@@ -59,6 +59,7 @@ typedef struct dbase_policydb dbase_t;
 
 #include "debug.h"
 #include "utilities.h"
+#include "compressed_file.h"
 
 #define SEMANAGE_CONF_FILE "semanage.conf"
 /* relative path names to enum semanage_paths to special files and
@@ -2054,60 +2055,27 @@ int semanage_direct_get_serial(semanage_handle_t * sh)
 
 int semanage_load_files(semanage_handle_t * sh, cil_db_t *cildb, char **filenames, int numfiles)
 {
-	int retval = 0;
-	FILE *fp;
-	ssize_t size;
-	char *data = NULL;
+	int i, retval = 0;
 	char *filename;
-	int i;
+	struct file_contents contents = {};
 
 	for (i = 0; i < numfiles; i++) {
 		filename = filenames[i];
 
-		if ((fp = fopen(filename, "rb")) == NULL) {
-			ERR(sh, "Could not open module file %s for reading.", filename);
-			goto cleanup;
-		}
-
-		if ((size = bunzip(sh, fp, &data)) <= 0) {
-			rewind(fp);
-			__fsetlocking(fp, FSETLOCKING_BYCALLER);
-
-			if (fseek(fp, 0, SEEK_END) != 0) {
-				ERR(sh, "Failed to determine size of file %s.", filename);
-				goto cleanup;
-			}
-			size = ftell(fp);
-			rewind(fp);
-
-			data = malloc(size);
-			if (fread(data, size, 1, fp) != 1) {
-				ERR(sh, "Failed to read file %s.", filename);
-				goto cleanup;
-			}
-		}
+		retval = map_compressed_file(sh, filename, &contents);
+		if (retval < 0)
+			return -1;
 
-		fclose(fp);
-		fp = NULL;
+		retval = cil_add_file(cildb, filename, contents.data, contents.len);
+		unmap_compressed_file(&contents);
 
-		retval = cil_add_file(cildb, filename, data, size);
 		if (retval != SEPOL_OK) {
 			ERR(sh, "Error while reading from file %s.", filename);
-			goto cleanup;
+			return -1;
 		}
-	
-		free(data);
-		data = NULL;
 	}
 
-	return retval;
-
-      cleanup:
-	if (fp != NULL) {
-		fclose(fp);
-	}
-	free(data);
-	return -1;
+	return 0;
 }
 
 /* 
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH userspace v2 4/6] libsemanage: clean up semanage_direct_commit() a bit
  2022-02-03 16:53 [PATCH userspace v2 0/6] Optionally rebuild policy store only if there were external changes to modules Ondrej Mosnacek
                   ` (2 preceding siblings ...)
  2022-02-03 16:53 ` [PATCH userspace v2 3/6] libsemanage: move compressed file handling into a separate object Ondrej Mosnacek
@ 2022-02-03 16:53 ` Ondrej Mosnacek
  2022-02-03 16:53 ` [PATCH userspace v2 5/6] libsemanage: optionally rebuild policy when modules are changed externally Ondrej Mosnacek
  2022-02-03 16:53 ` [PATCH userspace v2 6/6] semodule: add command-line option to detect module changes Ondrej Mosnacek
  5 siblings, 0 replies; 9+ messages in thread
From: Ondrej Mosnacek @ 2022-02-03 16:53 UTC (permalink / raw)
  To: selinux

Do some minor cosmetic cleanup, mainly to eliminate the 'rebuilt' goto
label.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
---
 libsemanage/src/direct_api.c | 91 ++++++++++++++++++------------------
 1 file changed, 45 insertions(+), 46 deletions(-)

diff --git a/libsemanage/src/direct_api.c b/libsemanage/src/direct_api.c
index 7eb6938b..f0bd7716 100644
--- a/libsemanage/src/direct_api.c
+++ b/libsemanage/src/direct_api.c
@@ -994,6 +994,16 @@ cleanup:
 	return status;
 }
 
+/* Files that must exist in order to skip policy rebuild. */
+static const int semanage_computed_files[] = {
+	SEMANAGE_STORE_KERNEL,
+	SEMANAGE_STORE_FC,
+	SEMANAGE_STORE_SEUSERS,
+	SEMANAGE_LINKED,
+	SEMANAGE_SEUSERS_LINKED,
+	SEMANAGE_USERS_EXTRA_LINKED
+};
+
 /* Copies a file from src to dst. If dst already exists then
  * overwrite it. If source doesn't exist then return success.
  * Returns 0 on success, -1 on error. */
@@ -1053,6 +1063,14 @@ static int semanage_direct_commit(semanage_handle_t * sh)
 	seusers_modified = seusers->dtable->is_modified(seusers->dbase);
 	fcontexts_modified = fcontexts->dtable->is_modified(fcontexts->dbase);
 
+	/* Before we do anything else, flush the join to its component parts.
+	 * This *does not* flush to disk automatically */
+	if (users->dtable->is_modified(users->dbase)) {
+		retval = users->dtable->flush(sh, users->dbase);
+		if (retval < 0)
+			goto cleanup;
+	}
+
 	/* Rebuild if explicitly requested or any module changes occurred. */
 	do_rebuild = sh->do_rebuild | sh->modules_modified;
 
@@ -1119,14 +1137,6 @@ static int semanage_direct_commit(semanage_handle_t * sh)
 		}
 	}
 
-	/* Before we do anything else, flush the join to its component parts.
-	 * This *does not* flush to disk automatically */
-	if (users->dtable->is_modified(users->dbase)) {
-		retval = users->dtable->flush(sh, users->dbase);
-		if (retval < 0)
-			goto cleanup;
-	}
-
 	/*
 	 * This is for systems that have already migrated with an older version
 	 * of semanage_migrate_store. The older version did not copy
@@ -1135,48 +1145,20 @@ static int semanage_direct_commit(semanage_handle_t * sh)
 	 * in order to skip re-linking are present; otherwise, we force
 	 * a rebuild.
 	 */
-	if (!do_rebuild) {
-		int files[] = {SEMANAGE_STORE_KERNEL,
-					   SEMANAGE_STORE_FC,
-					   SEMANAGE_STORE_SEUSERS,
-					   SEMANAGE_LINKED,
-					   SEMANAGE_SEUSERS_LINKED,
-					   SEMANAGE_USERS_EXTRA_LINKED};
-
-		for (i = 0; i < (int) ARRAY_SIZE(files); i++) {
-			path = semanage_path(SEMANAGE_TMP, files[i]);
-			if (stat(path, &sb) != 0) {
-				if (errno != ENOENT) {
-					ERR(sh, "Unable to access %s: %s\n", path, strerror(errno));
-					retval = -1;
-					goto cleanup;
-				}
-
-				do_rebuild = 1;
-				goto rebuild;
+	for (i = 0; !do_rebuild && i < (int)ARRAY_SIZE(semanage_computed_files); i++) {
+		path = semanage_path(SEMANAGE_TMP, semanage_computed_files[i]);
+		if (stat(path, &sb) != 0) {
+			if (errno != ENOENT) {
+				ERR(sh, "Unable to access %s: %s\n", path, strerror(errno));
+				retval = -1;
+				goto cleanup;
 			}
+
+			do_rebuild = 1;
+			break;
 		}
 	}
 
-rebuild:
-	/*
-	 * Now that we know whether or not a rebuild is required,
-	 * we can determine what else needs to be done.
-	 * We need to write the kernel policy if we are rebuilding
-	 * or if any other policy component that lives in the kernel
-	 * policy has been modified.
-	 * We need to install the policy files if any of the managed files
-	 * that live under /etc/selinux (kernel policy, seusers, file contexts)
-	 * will be modified.
-	 */
-	do_write_kernel = do_rebuild | ports_modified | ibpkeys_modified |
-		ibendports_modified |
-		bools->dtable->is_modified(bools->dbase) |
-		ifaces->dtable->is_modified(ifaces->dbase) |
-		nodes->dtable->is_modified(nodes->dbase) |
-		users->dtable->is_modified(users_base->dbase);
-	do_install = do_write_kernel | seusers_modified | fcontexts_modified;
-
 	/*
 	 * If there were policy changes, or explicitly requested, or
 	 * any required files are missing, rebuild the policy.
@@ -1330,6 +1312,23 @@ rebuild:
 		}
 	}
 
+	/*
+	 * Determine what else needs to be done.
+	 * We need to write the kernel policy if we are rebuilding
+	 * or if any other policy component that lives in the kernel
+	 * policy has been modified.
+	 * We need to install the policy files if any of the managed files
+	 * that live under /etc/selinux (kernel policy, seusers, file contexts)
+	 * will be modified.
+	 */
+	do_write_kernel = do_rebuild | ports_modified | ibpkeys_modified |
+		ibendports_modified |
+		bools->dtable->is_modified(bools->dbase) |
+		ifaces->dtable->is_modified(ifaces->dbase) |
+		nodes->dtable->is_modified(nodes->dbase) |
+		users->dtable->is_modified(users_base->dbase);
+	do_install = do_write_kernel | seusers_modified | fcontexts_modified;
+
 	/* Attach our databases to the policydb we just created or loaded. */
 	dbase_policydb_attach((dbase_policydb_t *) pusers_base->dbase, out);
 	dbase_policydb_attach((dbase_policydb_t *) pports->dbase, out);
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH userspace v2 5/6] libsemanage: optionally rebuild policy when modules are changed externally
  2022-02-03 16:53 [PATCH userspace v2 0/6] Optionally rebuild policy store only if there were external changes to modules Ondrej Mosnacek
                   ` (3 preceding siblings ...)
  2022-02-03 16:53 ` [PATCH userspace v2 4/6] libsemanage: clean up semanage_direct_commit() a bit Ondrej Mosnacek
@ 2022-02-03 16:53 ` Ondrej Mosnacek
  2022-02-03 16:53 ` [PATCH userspace v2 6/6] semodule: add command-line option to detect module changes Ondrej Mosnacek
  5 siblings, 0 replies; 9+ messages in thread
From: Ondrej Mosnacek @ 2022-02-03 16:53 UTC (permalink / raw)
  To: selinux

In Fedora/RHEL's selinux-policy package we ship a pre-built SELinux
policy store in the RPMs. When updating the main policy RPM, care must
be taken to rebuild the policy using `semodule -B` if there are any
other SELinux modules installed (whether shipped via another RPM or
manually installed locally).

However, this way of shipping/managing the policy creates complications
on systems, where system files are managed by rpm-ostree (such as Fedora
CoreOS or Red Hat CoreOS), where the "package update" process is more
sophisticated.

(Disclaimer: The following is written according to my current limited
understanding of rpm-ostree and may not be entirely accurate, but the
gist of it should match the reality.)

Basically, one can think of rpm-ostree as a kind of Git for system
files. The package content is provided on a "branch", where each
"commit" represents a set of package updates layered on top of the
previous commit (i.e. it is a rolling release with some defined
package content snapshots). The user can then maintain their own branch
with additional package updates/installations/... and "rebase" it on top
of the main branch as needed. On top of that, the user can also have
additional configuration files (or modifications to existing files) in
/etc, which represent an additional layer on top of the package content.

When updating the system (i.e. rebasing on a new "commit" of the "main
branch"), the files on the running system are not touched and the new
system state is prepared under a new root directory, which is chrooted
into on the next reboot.

When an rpm-ostree system is updated, there are three moments when the
SELinux module store needs to be rebuilt to ensure that all modules are
included in the binary policy:
1. When the local RPM installations are applied on top of the base
   system snapshot.
2. When local user configuartion is applied on top of that.
3. On system shutdown, to ensure that any changes in local configuration
   performed since (2.) are reflected in the final new system image.

Forcing a full rebuild at each step is not optimal and in many cases is
not necessary, as the user may not have any custom modules installed.

Thus, this patch extends libsemanage to compute a checksum of the
content of all enabled modules, which is stored in the store, and adds a
flag to the libsemanage handle that instructs it to check the module
content checksum against the one from the last successful transaction
and force a full policy rebuild if they don't match.

This will allow rpm-ostree systems to potentially reduce delays when
reconciling the module store when applying updates.

I wasn't able to measure any noticeable overhead of the hash
computation, which is now added for every transaction (both before and
after this change a full policy rebuild took about 7 seconds on my test
x86 VM). With the new option check_ext_changes enabled, rebuilding a
policy store with unchanged modules took only about 0.96 seconds.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
---
 libsemanage/include/semanage/handle.h |   5 +
 libsemanage/src/direct_api.c          | 187 +++++++++++++++++++++-----
 libsemanage/src/handle.c              |  11 +-
 libsemanage/src/handle.h              |   1 +
 libsemanage/src/libsemanage.map       |   1 +
 libsemanage/src/modules.c             |   4 +-
 libsemanage/src/modules.h             |   3 +
 libsemanage/src/semanage_store.c      |   1 +
 libsemanage/src/semanage_store.h      |   1 +
 9 files changed, 175 insertions(+), 39 deletions(-)

diff --git a/libsemanage/include/semanage/handle.h b/libsemanage/include/semanage/handle.h
index 946d69bc..0157be4f 100644
--- a/libsemanage/include/semanage/handle.h
+++ b/libsemanage/include/semanage/handle.h
@@ -66,6 +66,11 @@ extern void semanage_set_reload(semanage_handle_t * handle, int do_reload);
  * 1 for yes, 0 for no (default) */
 extern void semanage_set_rebuild(semanage_handle_t * handle, int do_rebuild);
 
+/* set whether to rebuild the policy on commit when potential changes
+ * to module files since last rebuild are detected,
+ * 1 for yes (default), 0 for no */
+extern void semanage_set_check_ext_changes(semanage_handle_t * handle, int do_check);
+
 /* Fills *compiler_path with the location of the hll compiler sh->conf->compiler_directory_path
  * corresponding to lang_ext.
  * Upon success returns 0, -1 on error. */
diff --git a/libsemanage/src/direct_api.c b/libsemanage/src/direct_api.c
index f0bd7716..d83941b0 100644
--- a/libsemanage/src/direct_api.c
+++ b/libsemanage/src/direct_api.c
@@ -33,6 +33,8 @@
 #include <unistd.h>
 #include <sys/stat.h>
 #include <sys/types.h>
+#include <sys/mman.h>
+#include <sys/wait.h>
 #include <limits.h>
 #include <errno.h>
 #include <dirent.h>
@@ -56,8 +58,7 @@
 #include "semanage_store.h"
 #include "database_policydb.h"
 #include "policy.h"
-#include <sys/mman.h>
-#include <sys/wait.h>
+#include "sha256.h"
 
 #define PIPE_READ 0
 #define PIPE_WRITE 1
@@ -450,7 +451,7 @@ static int parse_module_headers(semanage_handle_t * sh, char *module_data,
 /* Writes a block of data to a file.  Returns 0 on success, -1 on
  * error. */
 static int write_file(semanage_handle_t * sh,
-		      const char *filename, char *data, size_t num_bytes)
+		      const char *filename, const char *data, size_t num_bytes)
 {
 	int out;
 
@@ -850,8 +851,21 @@ cleanup:
 	return ret;
 }
 
+static void update_checksum_with_len(Sha256Context *context, size_t s)
+{
+	int i;
+	uint8_t buffer[8];
+
+	for (i = 0; i < 8; i++) {
+		buffer[i] = s & 0xff;
+		s >>= 8;
+	}
+	Sha256Update(context, buffer, 8);
+}
+
 static int semanage_compile_module(semanage_handle_t *sh,
-				semanage_module_info_t *modinfo)
+				   semanage_module_info_t *modinfo,
+				   Sha256Context *context)
 {
 	char cil_path[PATH_MAX];
 	char hll_path[PATH_MAX];
@@ -922,6 +936,11 @@ static int semanage_compile_module(semanage_handle_t *sh,
 		goto cleanup;
 	}
 
+	if (context) {
+		update_checksum_with_len(context, cil_data_len);
+		Sha256Update(context, cil_data, cil_data_len);
+	}
+
 	status = write_compressed_file(sh, cil_path, cil_data, cil_data_len);
 	if (status == -1) {
 		ERR(sh, "Failed to write %s\n", cil_path);
@@ -950,18 +969,40 @@ cleanup:
 	return status;
 }
 
+static int modinfo_cmp(const void *a, const void *b)
+{
+	const semanage_module_info_t *ma = a;
+	const semanage_module_info_t *mb = b;
+
+	return strcmp(ma->name, mb->name);
+}
+
 static int semanage_compile_hll_modules(semanage_handle_t *sh,
-				semanage_module_info_t *modinfos,
-				int num_modinfos)
+					semanage_module_info_t *modinfos,
+					int num_modinfos,
+					char *cil_checksum)
 {
-	int status = 0;
-	int i;
+	/* to be incremented when checksum input data format changes */
+	static const size_t CHECKSUM_EPOCH = 1;
+
+	int i, status = 0;
 	char cil_path[PATH_MAX];
 	struct stat sb;
+	Sha256Context context;
+	SHA256_HASH hash;
+	struct file_contents contents = {};
 
 	assert(sh);
 	assert(modinfos);
 
+	/* Sort modules by name to get consistent ordering. */
+	qsort(modinfos, num_modinfos, sizeof(*modinfos), &modinfo_cmp);
+
+	Sha256Initialise(&context);
+	update_checksum_with_len(&context, CHECKSUM_EPOCH);
+
+	/* prefix with module count to avoid collisions */
+	update_checksum_with_len(&context, num_modinfos);
 	for (i = 0; i < num_modinfos; i++) {
 		status = semanage_module_get_path(
 				sh,
@@ -969,29 +1010,91 @@ static int semanage_compile_hll_modules(semanage_handle_t *sh,
 				SEMANAGE_MODULE_PATH_CIL,
 				cil_path,
 				sizeof(cil_path));
-		if (status != 0) {
-			goto cleanup;
-		}
+		if (status != 0)
+			return -1;
 
-		if (semanage_get_ignore_module_cache(sh) == 0 &&
-				(status = stat(cil_path, &sb)) == 0) {
-			continue;
-		}
-		if (status != 0 && errno != ENOENT) {
-			ERR(sh, "Unable to access %s: %s\n", cil_path, strerror(errno));
-			goto cleanup; //an error in the "stat" call
+		if (!semanage_get_ignore_module_cache(sh)) {
+			status = stat(cil_path, &sb);
+			if (status == 0) {
+				status = map_compressed_file(sh, cil_path, &contents);
+				if (status < 0) {
+					ERR(sh, "Error mapping file: %s", cil_path);
+					return -1;
+				}
+
+				/* prefix with length to avoid collisions */
+				update_checksum_with_len(&context, contents.len);
+				Sha256Update(&context, contents.data, contents.len);
+
+				unmap_compressed_file(&contents);
+				continue;
+			} else if (errno != ENOENT) {
+				ERR(sh, "Unable to access %s: %s\n", cil_path,
+				    strerror(errno));
+				return -1; //an error in the "stat" call
+			}
 		}
 
-		status = semanage_compile_module(sh, &modinfos[i]);
-		if (status < 0) {
-			goto cleanup;
+		status = semanage_compile_module(sh, &modinfos[i], &context);
+		if (status < 0)
+			return -1;
+	}
+	Sha256Finalise(&context, &hash);
+
+	semanage_hash_to_checksum_string(hash.bytes, cil_checksum);
+	return 0;
+}
+
+static int semanage_compare_checksum(semanage_handle_t *sh, const char *reference)
+{
+	const char *path = semanage_path(SEMANAGE_TMP, SEMANAGE_MODULES_CHECKSUM);
+	struct stat sb;
+	int fd, retval;
+	char *data;
+
+	fd = open(path, O_RDONLY);
+	if (fd == -1) {
+		if (errno != ENOENT) {
+			ERR(sh, "Unable to open %s: %s\n", path, strerror(errno));
+			return -1;
 		}
+		/* Checksum file not present - force a rebuild. */
+		return 1;
+	}
+
+	if (fstat(fd, &sb) == -1) {
+		ERR(sh, "Unable to stat %s\n", path);
+		retval = -1;
+		goto out_close;
 	}
 
-	status = 0;
+	if (sb.st_size != (off_t)CHECKSUM_CONTENT_SIZE) {
+		/* Incompatible/invalid hash type - just force a rebuild. */
+		WARN(sh, "Module checksum invalid - forcing a rebuild\n");
+		retval = 1;
+		goto out_close;
+	}
 
-cleanup:
-	return status;
+	data = mmap(NULL, CHECKSUM_CONTENT_SIZE, PROT_READ, MAP_PRIVATE, fd, 0);
+	if (data == MAP_FAILED) {
+		ERR(sh, "Unable to mmap %s\n", path);
+		retval = -1;
+		goto out_close;
+	}
+
+	retval = memcmp(data, reference, CHECKSUM_CONTENT_SIZE) != 0;
+	munmap(data, sb.st_size);
+out_close:
+	close(fd);
+	return retval;
+}
+
+static int semanage_write_modules_checksum(semanage_handle_t *sh,
+					   const char *checksum)
+{
+	const char *path = semanage_path(SEMANAGE_TMP, SEMANAGE_MODULES_CHECKSUM);
+
+	return write_file(sh, path, checksum, CHECKSUM_CONTENT_SIZE);
 }
 
 /* Files that must exist in order to skip policy rebuild. */
@@ -1030,6 +1133,7 @@ static int semanage_direct_commit(semanage_handle_t * sh)
 	semanage_module_info_t *modinfos = NULL;
 	mode_t mask = umask(0077);
 	struct stat sb;
+	char modules_checksum[CHECKSUM_CONTENT_SIZE + 1 /* '\0' */];
 
 	int do_rebuild, do_write_kernel, do_install;
 	int fcontexts_modified, ports_modified, seusers_modified,
@@ -1159,28 +1263,45 @@ static int semanage_direct_commit(semanage_handle_t * sh)
 		}
 	}
 
-	/*
-	 * If there were policy changes, or explicitly requested, or
-	 * any required files are missing, rebuild the policy.
-	 */
-	if (do_rebuild) {
-		/* =================== Module expansion =============== */
-
+	if (do_rebuild || sh->check_ext_changes) {
 		retval = semanage_get_active_modules(sh, &modinfos, &num_modinfos);
 		if (retval < 0) {
 			goto cleanup;
 		}
 
+		/* No modules - nothing to rebuild. */
 		if (num_modinfos == 0) {
 			goto cleanup;
 		}
 
-		retval = semanage_compile_hll_modules(sh, modinfos, num_modinfos);
+		retval = semanage_compile_hll_modules(sh, modinfos, num_modinfos,
+						      modules_checksum);
 		if (retval < 0) {
 			ERR(sh, "Failed to compile hll files into cil files.\n");
 			goto cleanup;
 		}
 
+		if (!do_rebuild && sh->check_ext_changes) {
+			retval = semanage_compare_checksum(sh, modules_checksum);
+			if (retval < 0)
+				goto cleanup;
+			do_rebuild = retval;
+		}
+
+		retval = semanage_write_modules_checksum(sh, modules_checksum);
+		if (retval < 0) {
+			ERR(sh, "Failed to write module checksum file.\n");
+			goto cleanup;
+		}
+	}
+
+	/*
+	 * If there were policy changes, or explicitly requested, or
+	 * any required files are missing, rebuild the policy.
+	 */
+	if (do_rebuild) {
+		/* =================== Module expansion =============== */
+
 		retval = semanage_get_cil_paths(sh, modinfos, num_modinfos, &mod_filenames);
 		if (retval < 0)
 			goto cleanup;
@@ -1703,7 +1824,7 @@ static int semanage_direct_extract(semanage_handle_t * sh,
 			goto cleanup;
 		}
 
-		rc = semanage_compile_module(sh, _modinfo);
+		rc = semanage_compile_module(sh, _modinfo, NULL);
 		if (rc < 0) {
 			goto cleanup;
 		}
diff --git a/libsemanage/src/handle.c b/libsemanage/src/handle.c
index bb1e6140..b2201ee3 100644
--- a/libsemanage/src/handle.c
+++ b/libsemanage/src/handle.c
@@ -116,20 +116,23 @@ semanage_handle_t *semanage_handle_create(void)
 
 void semanage_set_rebuild(semanage_handle_t * sh, int do_rebuild)
 {
-
 	assert(sh != NULL);
 
 	sh->do_rebuild = do_rebuild;
-	return;
 }
 
 void semanage_set_reload(semanage_handle_t * sh, int do_reload)
 {
-
 	assert(sh != NULL);
 
 	sh->do_reload = do_reload;
-	return;
+}
+
+void semanage_set_check_ext_changes(semanage_handle_t * sh, int do_check)
+{
+	assert(sh != NULL);
+
+	sh->check_ext_changes = do_check;
 }
 
 int semanage_get_hll_compiler_path(semanage_handle_t *sh,
diff --git a/libsemanage/src/handle.h b/libsemanage/src/handle.h
index e1ce83ba..4d2aae8f 100644
--- a/libsemanage/src/handle.h
+++ b/libsemanage/src/handle.h
@@ -61,6 +61,7 @@ struct semanage_handle {
 	int is_in_transaction;
 	int do_reload;		/* whether to reload policy after commit */
 	int do_rebuild;		/* whether to rebuild policy if there were no changes */
+	int check_ext_changes;	/* whether to rebuild if external changes are detected via checksum */
 	int commit_err;		/* set by semanage_direct_commit() if there are
 				 * any errors when building or committing the
 				 * sandbox to kernel policy at /etc/selinux
diff --git a/libsemanage/src/libsemanage.map b/libsemanage/src/libsemanage.map
index 00259fc8..c8214b26 100644
--- a/libsemanage/src/libsemanage.map
+++ b/libsemanage/src/libsemanage.map
@@ -348,4 +348,5 @@ LIBSEMANAGE_1.1 {
 
 LIBSEMANAGE_3.4 {
     semanage_module_compute_checksum;
+    semanage_set_check_ext_changes;
 } LIBSEMANAGE_1.1;
diff --git a/libsemanage/src/modules.c b/libsemanage/src/modules.c
index fe937519..c3bd90ac 100644
--- a/libsemanage/src/modules.c
+++ b/libsemanage/src/modules.c
@@ -979,9 +979,9 @@ int semanage_module_remove_key(semanage_handle_t *sh,
 }
 
 static const char CHECKSUM_TYPE[] = "sha256";
-static const size_t CHECKSUM_CONTENT_SIZE = sizeof(CHECKSUM_TYPE) + 1 + 2 * SHA256_HASH_SIZE;
+const size_t CHECKSUM_CONTENT_SIZE = sizeof(CHECKSUM_TYPE) + 1 + 2 * SHA256_HASH_SIZE;
 
-static void semanage_hash_to_checksum_string(const uint8_t *hash, char *checksum)
+void semanage_hash_to_checksum_string(const uint8_t *hash, char *checksum)
 {
 	size_t i;
 
diff --git a/libsemanage/src/modules.h b/libsemanage/src/modules.h
index 64d4a157..cf2432c5 100644
--- a/libsemanage/src/modules.h
+++ b/libsemanage/src/modules.h
@@ -102,4 +102,7 @@ int semanage_module_get_path(semanage_handle_t *sh,
 			     char *path,
 			     size_t len);
 
+extern const size_t CHECKSUM_CONTENT_SIZE;
+void semanage_hash_to_checksum_string(const uint8_t *hash, char *checksum);
+
 #endif
diff --git a/libsemanage/src/semanage_store.c b/libsemanage/src/semanage_store.c
index 633ee731..767f05cb 100644
--- a/libsemanage/src/semanage_store.c
+++ b/libsemanage/src/semanage_store.c
@@ -115,6 +115,7 @@ static const char *semanage_sandbox_paths[SEMANAGE_STORE_NUM_PATHS] = {
 	"/disable_dontaudit",
 	"/preserve_tunables",
 	"/modules/disabled",
+	"/modules_checksum",
 	"/policy.kern",
 	"/file_contexts.local",
 	"/file_contexts.homedirs",
diff --git a/libsemanage/src/semanage_store.h b/libsemanage/src/semanage_store.h
index b9ec5664..1fc77da8 100644
--- a/libsemanage/src/semanage_store.h
+++ b/libsemanage/src/semanage_store.h
@@ -60,6 +60,7 @@ enum semanage_sandbox_defs {
 	SEMANAGE_DISABLE_DONTAUDIT,
 	SEMANAGE_PRESERVE_TUNABLES,
 	SEMANAGE_MODULES_DISABLED,
+	SEMANAGE_MODULES_CHECKSUM,
 	SEMANAGE_STORE_KERNEL,
 	SEMANAGE_STORE_FC_LOCAL,
 	SEMANAGE_STORE_FC_HOMEDIRS,
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH userspace v2 6/6] semodule: add command-line option to detect module changes
  2022-02-03 16:53 [PATCH userspace v2 0/6] Optionally rebuild policy store only if there were external changes to modules Ondrej Mosnacek
                   ` (4 preceding siblings ...)
  2022-02-03 16:53 ` [PATCH userspace v2 5/6] libsemanage: optionally rebuild policy when modules are changed externally Ondrej Mosnacek
@ 2022-02-03 16:53 ` Ondrej Mosnacek
  5 siblings, 0 replies; 9+ messages in thread
From: Ondrej Mosnacek @ 2022-02-03 16:53 UTC (permalink / raw)
  To: selinux

Add a new command-line option "--rebuild-if-modules-changed" to control
the newly introduced check_ext_changes libsemanage flag.

For example, running `semodule --rebuild-if-modules-changed` will ensure
that any externally added/removed modules (e.g. by an RPM transaction)
are reflected in the compiled policy, while skipping the most expensive
part of the rebuild if no module change was deteceted since the last
libsemanage transaction.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
---
 policycoreutils/semodule/semodule.8 |  7 +++++++
 policycoreutils/semodule/semodule.c | 32 ++++++++++++++++++++++-------
 2 files changed, 32 insertions(+), 7 deletions(-)

diff --git a/policycoreutils/semodule/semodule.8 b/policycoreutils/semodule/semodule.8
index 3a2fb21c..d1735d21 100644
--- a/policycoreutils/semodule/semodule.8
+++ b/policycoreutils/semodule/semodule.8
@@ -23,6 +23,13 @@ force a reload of policy
 .B \-B, \-\-build
 force a rebuild of policy (also reloads unless \-n is used)
 .TP
+.B \-\-rebuild-if-modules-changed
+Force a rebuild of the policy if any changes to module content are detected
+(by comparing with checksum from the last transaction).  One can use this
+instead of \-B to ensure that any changes to the module store done by an
+external tool (e.g. a package manager) are applied, while automatically
+skipping the rebuild if there are no new changes.
+.TP
 .B \-D, \-\-disable_dontaudit
 Temporarily remove dontaudits from policy.  Reverts whenever policy is rebuilt
 .TP
diff --git a/policycoreutils/semodule/semodule.c b/policycoreutils/semodule/semodule.c
index f4a76289..1ed8e690 100644
--- a/policycoreutils/semodule/semodule.c
+++ b/policycoreutils/semodule/semodule.c
@@ -47,6 +47,7 @@ static int verbose;
 static int reload;
 static int no_reload;
 static int build;
+static int check_ext_changes;
 static int disable_dontaudit;
 static int preserve_tunables;
 static int ignore_module_cache;
@@ -149,6 +150,9 @@ static void usage(char *progname)
 	printf("  -c, --cil extract module as cil. This only affects module extraction.\n");
 	printf("  -H, --hll extract module as hll. This only affects module extraction.\n");
 	printf("  -m, --checksum   print module checksum (SHA256).\n");
+	printf("      --rebuild-if-modules-changed\n"
+	       "                   force policy rebuild if module content changed since\n"
+	       "                   last rebuild (based on checksum)\n");
 }
 
 /* Sets the global mode variable to new_mode, but only if no other
@@ -180,6 +184,7 @@ static void set_mode(enum client_modes new_mode, char *arg)
 static void parse_command_line(int argc, char **argv)
 {
 	static struct option opts[] = {
+		{"rebuild-if-modules-changed", 0, NULL, '\0'},
 		{"store", required_argument, NULL, 's'},
 		{"base", required_argument, NULL, 'b'},
 		{"help", 0, NULL, 'h'},
@@ -207,15 +212,26 @@ static void parse_command_line(int argc, char **argv)
 	};
 	int extract_selected = 0;
 	int cil_hll_set = 0;
-	int i;
+	int i, longind;
 	verbose = 0;
 	reload = 0;
 	no_reload = 0;
+	check_ext_changes = 0;
 	priority = 400;
 	while ((i =
-		getopt_long(argc, argv, "s:b:hi:l::vr:u:RnNBDCPX:e:d:p:S:E:cHm", opts,
-			    NULL)) != -1) {
+		getopt_long(argc, argv, "s:b:hi:l::vr:u:RnNBDCPX:e:d:p:S:E:cHm",
+			    opts, &longind)) != -1) {
 		switch (i) {
+		case '\0':
+			switch(longind) {
+			case 0: /* --rebuild-if-modules-changed */
+				check_ext_changes = 1;
+				break;
+			default:
+				usage(argv[0]);
+				exit(1);
+			}
+			break;
 		case 'b':
 			fprintf(stderr, "The --base option is deprecated. Use --install instead.\n");
 			set_mode(INSTALL_M, optarg);
@@ -300,13 +316,13 @@ static void parse_command_line(int argc, char **argv)
 			}
 		}
 	}
-	if ((build || reload) && num_commands) {
+	if ((build || reload || check_ext_changes) && num_commands) {
 		fprintf(stderr,
 			"build or reload should not be used with other commands\n");
 		usage(argv[0]);
 		exit(1);
 	}
-	if (num_commands == 0 && reload == 0 && build == 0) {
+	if (num_commands == 0 && reload == 0 && build == 0 && check_ext_changes == 0) {
 		fprintf(stderr, "At least one mode must be specified.\n");
 		usage(argv[0]);
 		exit(1);
@@ -395,7 +411,7 @@ int main(int argc, char *argv[])
 
 	cil_set_log_level(CIL_ERR + verbose);
 
-	if (build)
+	if (build || check_ext_changes)
 		commit = 1;
 
 	sh = semanage_handle_create();
@@ -434,7 +450,7 @@ int main(int argc, char *argv[])
 		}
 	}
 
-	if (build) {
+	if (build || check_ext_changes) {
 		if ((result = semanage_begin_transaction(sh)) < 0) {
 			fprintf(stderr, "%s:  Could not begin transaction:  %s\n",
 				argv[0], errno ? strerror(errno) : "");
@@ -807,6 +823,8 @@ cleanup_disable:
 			semanage_set_reload(sh, 0);
 		if (build)
 			semanage_set_rebuild(sh, 1);
+		if (check_ext_changes)
+			semanage_set_check_ext_changes(sh, 1);
 		if (disable_dontaudit)
 			semanage_set_disable_dontaudit(sh, 1);
 		else if (build)
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* Re: [PATCH userspace v2 1/6] libsemanage: add missing include to boolean_record.c
  2022-02-03 16:53 ` [PATCH userspace v2 1/6] libsemanage: add missing include to boolean_record.c Ondrej Mosnacek
@ 2022-02-11 21:51   ` James Carter
  2022-02-18 18:42     ` James Carter
  0 siblings, 1 reply; 9+ messages in thread
From: James Carter @ 2022-02-11 21:51 UTC (permalink / raw)
  To: Ondrej Mosnacek; +Cc: SElinux list

On Fri, Feb 4, 2022 at 3:46 AM Ondrej Mosnacek <omosnace@redhat.com> wrote:
>
> It uses asprintf(3), but doesn't directly include <stdio.h> - fix it.
>
> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>

For this series:
Acked-by: James Carter <jwcart2@gmail.com>

> ---
>  libsemanage/src/boolean_record.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/libsemanage/src/boolean_record.c b/libsemanage/src/boolean_record.c
> index 95f3a862..40dc6545 100644
> --- a/libsemanage/src/boolean_record.c
> +++ b/libsemanage/src/boolean_record.c
> @@ -7,6 +7,9 @@
>   */
>
>  #include <string.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +
>  #include <sepol/boolean_record.h>
>
>  typedef sepol_bool_t semanage_bool_t;
> @@ -20,7 +23,6 @@ typedef semanage_bool_key_t record_key_t;
>  #include "boolean_internal.h"
>  #include "handle.h"
>  #include "database.h"
> -#include <stdlib.h>
>  #include <selinux/selinux.h>
>
>  /* Key */
> --
> 2.34.1
>

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH userspace v2 1/6] libsemanage: add missing include to boolean_record.c
  2022-02-11 21:51   ` James Carter
@ 2022-02-18 18:42     ` James Carter
  0 siblings, 0 replies; 9+ messages in thread
From: James Carter @ 2022-02-18 18:42 UTC (permalink / raw)
  To: Ondrej Mosnacek; +Cc: SElinux list

On Fri, Feb 11, 2022 at 4:51 PM James Carter <jwcart2@gmail.com> wrote:
>
> On Fri, Feb 4, 2022 at 3:46 AM Ondrej Mosnacek <omosnace@redhat.com> wrote:
> >
> > It uses asprintf(3), but doesn't directly include <stdio.h> - fix it.
> >
> > Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
>
> For this series:
> Acked-by: James Carter <jwcart2@gmail.com>
>
This series has been merged.
Thanks,
Jim

> > ---
> >  libsemanage/src/boolean_record.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/libsemanage/src/boolean_record.c b/libsemanage/src/boolean_record.c
> > index 95f3a862..40dc6545 100644
> > --- a/libsemanage/src/boolean_record.c
> > +++ b/libsemanage/src/boolean_record.c
> > @@ -7,6 +7,9 @@
> >   */
> >
> >  #include <string.h>
> > +#include <stdio.h>
> > +#include <stdlib.h>
> > +
> >  #include <sepol/boolean_record.h>
> >
> >  typedef sepol_bool_t semanage_bool_t;
> > @@ -20,7 +23,6 @@ typedef semanage_bool_key_t record_key_t;
> >  #include "boolean_internal.h"
> >  #include "handle.h"
> >  #include "database.h"
> > -#include <stdlib.h>
> >  #include <selinux/selinux.h>
> >
> >  /* Key */
> > --
> > 2.34.1
> >

^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2022-02-18 18:42 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-02-03 16:53 [PATCH userspace v2 0/6] Optionally rebuild policy store only if there were external changes to modules Ondrej Mosnacek
2022-02-03 16:53 ` [PATCH userspace v2 1/6] libsemanage: add missing include to boolean_record.c Ondrej Mosnacek
2022-02-11 21:51   ` James Carter
2022-02-18 18:42     ` James Carter
2022-02-03 16:53 ` [PATCH userspace v2 2/6] semodule,libsemanage: move module hashing into libsemanage Ondrej Mosnacek
2022-02-03 16:53 ` [PATCH userspace v2 3/6] libsemanage: move compressed file handling into a separate object Ondrej Mosnacek
2022-02-03 16:53 ` [PATCH userspace v2 4/6] libsemanage: clean up semanage_direct_commit() a bit Ondrej Mosnacek
2022-02-03 16:53 ` [PATCH userspace v2 5/6] libsemanage: optionally rebuild policy when modules are changed externally Ondrej Mosnacek
2022-02-03 16:53 ` [PATCH userspace v2 6/6] semodule: add command-line option to detect module changes Ondrej Mosnacek

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