[PATCH v6 0/2] userspace: Implement new format of filename trans rules

[PATCH v6 0/2] userspace: Implement new format of filename trans rules

[Ondrej Mosnacek]

These patches are the userspace side of the following kernel commits:
c3a276111ea2 ("selinux: optimize storage of filename transitions") [1]
430059024389 ("selinux: implement new format of filename transitions") [2].

The first patch changes libsepol's internal representation of filename
transition rules in a way similar to the kernel commit.

The second patch then builds upon that and implements reading and
writing of the new binary policy format that uses this representation
also in the data layout.

See individual patches for more details.

NOTE: This series unfortunately breaks the build of setools. Moreover,
when an existing build of setools dynamically links against the new
libsepol, it segfaults. Sadly, there doesn't seem to be a nice way of
handling this, since setools relies on non-public libsepol policydb
API/ABI. There is a draft PR that adapts setools to these changes here:
https://github.com/SELinuxProject/setools/pull/50

See also this discussion about the setools impact:
https://lore.kernel.org/selinux/daeae1d9-de29-aae0-6bde-3ad3427a5d42@tycho.nsa.gov/

Changes in v6:
 - simplify the interface of policydb_filetrans_insert()
   - i.e. make it possible to pass NULL to name_alloc to simplify most
     callers

Changes in v5:
 - fix comment in filename_trans_read() to not change when being moved
 - fix filename_trans_check_datum()
   - destroy temporary ebitmaps at return
   - actually iterate through datums

Changes in v4:
 - rebased on top of latest master branch

Changes in v3:
 - fixed the change in dispol.c to match the rest of the code
 - renamed the helper functions to use the "_compat" suffix rather than
   "_old" and "_new"

Changes in v2:
 - fixed counting rules when reading the new policy format

[1] https://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux.git/commit/?id=c3a276111ea2572399281988b3129683e2a6b60b
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=4300590243895ac39e8c97a2f5acd004dad8a42f

Ondrej Mosnacek (2):
  libsepol,checkpolicy: optimize storage of filename transitions
  libsepol: implement POLICYDB_VERSION_COMP_FTRANS

 checkpolicy/policy_define.c                |  49 +---
 checkpolicy/test/dispol.c                  |  20 +-
 libsepol/cil/src/cil_binary.c              |  26 +-
 libsepol/include/sepol/policydb/policydb.h |  18 +-
 libsepol/src/expand.c                      |  56 +---
 libsepol/src/kernel_to_cil.c               |  24 +-
 libsepol/src/kernel_to_conf.c              |  24 +-
 libsepol/src/policydb.c                    | 314 +++++++++++++++++----
 libsepol/src/write.c                       | 101 +++++--
 9 files changed, 433 insertions(+), 199 deletions(-)

-- 
2.26.2

[PATCH v6 1/2] libsepol,checkpolicy: optimize storage of filename transitions

[Ondrej Mosnacek]

In preparation to support a new policy format with a more optimal
representation of filename transition rules, this patch applies an
equivalent change from kernel commit c3a276111ea2 ("selinux: optimize
storage of filename transitions").

See the kernel commit's description [1] for the rationale behind this
representation. This change doesn't bring any measurable difference of
policy build performance (semodule -B) on Fedora.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux.git/commit/?id=c3a276111ea2572399281988b3129683e2a6b60b

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
---
 checkpolicy/policy_define.c                |  49 +++-----
 checkpolicy/test/dispol.c                  |  20 +++-
 libsepol/cil/src/cil_binary.c              |  26 ++---
 libsepol/include/sepol/policydb/policydb.h |  15 ++-
 libsepol/src/expand.c                      |  56 ++-------
 libsepol/src/kernel_to_cil.c               |  24 +++-
 libsepol/src/kernel_to_conf.c              |  24 +++-
 libsepol/src/policydb.c                    | 125 +++++++++++++++------
 libsepol/src/write.c                       |  46 ++++----
 9 files changed, 210 insertions(+), 175 deletions(-)

diff --git a/checkpolicy/policy_define.c b/checkpolicy/policy_define.c
index c6733fa4..395f6228 100644
--- a/checkpolicy/policy_define.c
+++ b/checkpolicy/policy_define.c
@@ -3303,8 +3303,6 @@ int define_filename_trans(void)
 	ebitmap_t e_stypes, e_ttypes;
 	ebitmap_t e_tclasses;
 	ebitmap_node_t *snode, *tnode, *cnode;
-	filename_trans_t *ft;
-	filename_trans_datum_t *ftdatum;
 	filename_trans_rule_t *ftr;
 	type_datum_t *typdatum;
 	uint32_t otype;
@@ -3388,40 +3386,19 @@ int define_filename_trans(void)
 	ebitmap_for_each_positive_bit(&e_tclasses, cnode, c) {
 		ebitmap_for_each_positive_bit(&e_stypes, snode, s) {
 			ebitmap_for_each_positive_bit(&e_ttypes, tnode, t) {
-				ft = calloc(1, sizeof(*ft));
-				if (!ft) {
-					yyerror("out of memory");
-					goto bad;
-				}
-				ft->stype = s+1;
-				ft->ttype = t+1;
-				ft->tclass = c+1;
-				ft->name = strdup(name);
-				if (!ft->name) {
-					yyerror("out of memory");
-					goto bad;
-				}
-
-				ftdatum = hashtab_search(policydbp->filename_trans,
-							 (hashtab_key_t)ft);
-				if (ftdatum) {
-					yyerror2("duplicate filename transition for: filename_trans %s %s %s:%s",
-						 name,
-						 policydbp->p_type_val_to_name[s],
-						 policydbp->p_type_val_to_name[t],
-						 policydbp->p_class_val_to_name[c]);
-					goto bad;
-				}
-
-				ftdatum = calloc(1, sizeof(*ftdatum));
-				if (!ftdatum) {
-					yyerror("out of memory");
-					goto bad;
-				}
-				rc = hashtab_insert(policydbp->filename_trans,
-						    (hashtab_key_t)ft,
-						    ftdatum);
-				if (rc) {
+				rc = policydb_filetrans_insert(
+					policydbp, s+1, t+1, c+1, name,
+					NULL, otype, NULL
+				);
+				if (rc != SEPOL_OK) {
+					if (rc == SEPOL_EEXIST) {
+						yyerror2("duplicate filename transition for: filename_trans %s %s %s:%s",
+							name,
+							policydbp->p_type_val_to_name[s],
+							policydbp->p_type_val_to_name[t],
+							policydbp->p_class_val_to_name[c]);
+						goto bad;
+					}
 					yyerror("out of memory");
 					goto bad;
 				}
diff --git a/checkpolicy/test/dispol.c b/checkpolicy/test/dispol.c
index d72d9fb3..8785b725 100644
--- a/checkpolicy/test/dispol.c
+++ b/checkpolicy/test/dispol.c
@@ -335,17 +335,25 @@ static int filenametr_display(hashtab_key_t key,
 			      hashtab_datum_t datum,
 			      void *ptr)
 {
-	struct filename_trans *ft = (struct filename_trans *)key;
+	struct filename_trans_key *ft = (struct filename_trans_key *)key;
 	struct filename_trans_datum *ftdatum = datum;
 	struct filenametr_display_args *args = ptr;
 	policydb_t *p = args->p;
 	FILE *fp = args->fp;
+	ebitmap_node_t *node;
+	uint32_t bit;
+
+	do {
+		ebitmap_for_each_positive_bit(&ftdatum->stypes, node, bit) {
+			display_id(p, fp, SYM_TYPES, bit, "");
+			display_id(p, fp, SYM_TYPES, ft->ttype - 1, "");
+			display_id(p, fp, SYM_CLASSES, ft->tclass - 1, ":");
+			display_id(p, fp, SYM_TYPES, ftdatum->otype - 1, "");
+			fprintf(fp, " %s\n", ft->name);
+		}
+		ftdatum = ftdatum->next;
+	} while (ftdatum);
 
-	display_id(p, fp, SYM_TYPES, ft->stype - 1, "");
-	display_id(p, fp, SYM_TYPES, ft->ttype - 1, "");
-	display_id(p, fp, SYM_CLASSES, ft->tclass - 1, ":");
-	display_id(p, fp, SYM_TYPES, ftdatum->otype - 1, "");
-	fprintf(fp, " %s\n", ft->name);
 	return 0;
 }
 
diff --git a/libsepol/cil/src/cil_binary.c b/libsepol/cil/src/cil_binary.c
index 62178d99..77266858 100644
--- a/libsepol/cil/src/cil_binary.c
+++ b/libsepol/cil/src/cil_binary.c
@@ -1131,11 +1131,10 @@ int __cil_typetransition_to_avtab(policydb_t *pdb, const struct cil_db *db, stru
 	class_datum_t *sepol_obj = NULL;
 	struct cil_list *class_list;
 	type_datum_t *sepol_result = NULL;
-	filename_trans_t *newkey = NULL;
-	filename_trans_datum_t *newdatum = NULL, *otype = NULL;
 	ebitmap_t src_bitmap, tgt_bitmap;
 	ebitmap_node_t *node1, *node2;
 	unsigned int i, j;
+	uint32_t otype;
 	struct cil_list_item *c;
 	char *name = DATUM(typetrans->name)->name;
 
@@ -1176,22 +1175,14 @@ int __cil_typetransition_to_avtab(policydb_t *pdb, const struct cil_db *db, stru
 				rc = __cil_get_sepol_class_datum(pdb, DATUM(c->data), &sepol_obj);
 				if (rc != SEPOL_OK) goto exit;
 
-				newkey = cil_calloc(1, sizeof(*newkey));
-				newdatum = cil_calloc(1, sizeof(*newdatum));
-				newkey->stype = sepol_src->s.value;
-				newkey->ttype = sepol_tgt->s.value;
-				newkey->tclass = sepol_obj->s.value;
-				newkey->name = cil_strdup(name);
-				newdatum->otype = sepol_result->s.value;
-
-				rc = hashtab_insert(pdb->filename_trans,
-						    (hashtab_key_t)newkey,
-						    newdatum);
+				rc = policydb_filetrans_insert(
+					pdb, sepol_src->s.value, sepol_tgt->s.value,
+					sepol_obj->s.value, name, NULL,
+					sepol_result->s.value, &otype
+				);
 				if (rc != SEPOL_OK) {
 					if (rc == SEPOL_EEXIST) {
-						otype = hashtab_search(pdb->filename_trans,
-								(hashtab_key_t)newkey);
-						if (newdatum->otype != otype->otype) {
+						if (sepol_result->s.value!= otype) {
 							cil_log(CIL_ERR, "Conflicting name type transition rules\n");
 						} else {
 							rc = SEPOL_OK;
@@ -1199,9 +1190,6 @@ int __cil_typetransition_to_avtab(policydb_t *pdb, const struct cil_db *db, stru
 					} else {
 						cil_log(CIL_ERR, "Out of memory\n");
 					}
-					free(newkey->name);
-					free(newkey);
-					free(newdatum);
 					if (rc != SEPOL_OK) {
 						goto exit;
 					}
diff --git a/libsepol/include/sepol/policydb/policydb.h b/libsepol/include/sepol/policydb/policydb.h
index 81b63fef..c3180c61 100644
--- a/libsepol/include/sepol/policydb/policydb.h
+++ b/libsepol/include/sepol/policydb/policydb.h
@@ -162,15 +162,16 @@ typedef struct role_allow {
 } role_allow_t;
 
 /* filename_trans rules */
-typedef struct filename_trans {
-	uint32_t stype;
+typedef struct filename_trans_key {
 	uint32_t ttype;
 	uint32_t tclass;
 	char *name;
-} filename_trans_t;
+} filename_trans_key_t;
 
 typedef struct filename_trans_datum {
-	uint32_t otype;		/* expected of new object */
+	ebitmap_t stypes;
+	uint32_t otype;
+	struct filename_trans_datum *next;
 } filename_trans_datum_t;
 
 /* Type attributes */
@@ -591,6 +592,7 @@ typedef struct policydb {
 
 	/* file transitions with the last path component */
 	hashtab_t filename_trans;
+	uint32_t filename_trans_count;
 
 	ebitmap_t *type_attr_map;
 
@@ -650,6 +652,11 @@ extern int policydb_load_isids(policydb_t * p, sidtab_t * s);
 
 extern int policydb_sort_ocontexts(policydb_t *p);
 
+extern int policydb_filetrans_insert(policydb_t *p, uint32_t stype,
+				     uint32_t ttype, uint32_t tclass,
+				     const char *name, char **name_alloc,
+				     uint32_t otype, uint32_t *present_otype);
+
 /* Deprecated */
 extern int policydb_context_isvalid(const policydb_t * p,
 				    const context_struct_t * c);
diff --git a/libsepol/src/expand.c b/libsepol/src/expand.c
index 529e1d35..19e48c50 100644
--- a/libsepol/src/expand.c
+++ b/libsepol/src/expand.c
@@ -1371,8 +1371,6 @@ static int copy_role_trans(expand_state_t * state, role_trans_rule_t * rules)
 static int expand_filename_trans(expand_state_t *state, filename_trans_rule_t *rules)
 {
 	unsigned int i, j;
-	filename_trans_t key, *new_trans;
-	filename_trans_datum_t *otype;
 	filename_trans_rule_t *cur_rule;
 	ebitmap_t stypes, ttypes;
 	ebitmap_node_t *snode, *tnode;
@@ -1380,7 +1378,7 @@ static int expand_filename_trans(expand_state_t *state, filename_trans_rule_t *r
 
 	cur_rule = rules;
 	while (cur_rule) {
-		uint32_t mapped_otype;
+		uint32_t mapped_otype, present_otype;
 
 		ebitmap_init(&stypes);
 		ebitmap_init(&ttypes);
@@ -1401,15 +1399,14 @@ static int expand_filename_trans(expand_state_t *state, filename_trans_rule_t *r
 
 		ebitmap_for_each_positive_bit(&stypes, snode, i) {
 			ebitmap_for_each_positive_bit(&ttypes, tnode, j) {
-				key.stype = i + 1;
-				key.ttype = j + 1;
-				key.tclass = cur_rule->tclass;
-				key.name = cur_rule->name;
-				otype = hashtab_search(state->out->filename_trans,
-						       (hashtab_key_t) &key);
-				if (otype) {
+				rc = policydb_filetrans_insert(
+					state->out, i + 1, j + 1,
+					cur_rule->tclass, cur_rule->name,
+					NULL, mapped_otype, &present_otype
+				);
+				if (rc == SEPOL_EEXIST) {
 					/* duplicate rule, ignore */
-					if (otype->otype == mapped_otype)
+					if (present_otype == mapped_otype)
 						continue;
 
 					ERR(state->handle, "Conflicting name-based type_transition %s %s:%s \"%s\":  %s vs %s",
@@ -1417,44 +1414,11 @@ static int expand_filename_trans(expand_state_t *state, filename_trans_rule_t *r
 					    state->out->p_type_val_to_name[j],
 					    state->out->p_class_val_to_name[cur_rule->tclass - 1],
 					    cur_rule->name,
-					    state->out->p_type_val_to_name[otype->otype - 1],
+					    state->out->p_type_val_to_name[present_otype - 1],
 					    state->out->p_type_val_to_name[mapped_otype - 1]);
 					return -1;
-				}
-
-				new_trans = calloc(1, sizeof(*new_trans));
-				if (!new_trans) {
-					ERR(state->handle, "Out of memory!");
-					return -1;
-				}
-
-				new_trans->name = strdup(cur_rule->name);
-				if (!new_trans->name) {
-					ERR(state->handle, "Out of memory!");
-					free(new_trans);
-					return -1;
-				}
-				new_trans->stype = i + 1;
-				new_trans->ttype = j + 1;
-				new_trans->tclass = cur_rule->tclass;
-
-				otype = calloc(1, sizeof(*otype));
-				if (!otype) {
-					ERR(state->handle, "Out of memory!");
-					free(new_trans->name);
-					free(new_trans);
-					return -1;
-				}
-				otype->otype = mapped_otype;
-
-				rc = hashtab_insert(state->out->filename_trans,
-						    (hashtab_key_t)new_trans,
-						    otype);
-				if (rc) {
+				} else if (rc < 0) {
 					ERR(state->handle, "Out of memory!");
-					free(otype);
-					free(new_trans->name);
-					free(new_trans);
 					return -1;
 				}
 			}
diff --git a/libsepol/src/kernel_to_cil.c b/libsepol/src/kernel_to_cil.c
index 958adc4c..c247b32f 100644
--- a/libsepol/src/kernel_to_cil.c
+++ b/libsepol/src/kernel_to_cil.c
@@ -1841,21 +1841,35 @@ struct map_filename_trans_args {
 
 static int map_filename_trans_to_str(hashtab_key_t key, void *data, void *arg)
 {
-	filename_trans_t *ft = (filename_trans_t *)key;
+	filename_trans_key_t *ft = (filename_trans_key_t *)key;
 	filename_trans_datum_t *datum = data;
 	struct map_filename_trans_args *map_args = arg;
 	struct policydb *pdb = map_args->pdb;
 	struct strs *strs = map_args->strs;
 	char *src, *tgt, *class, *filename, *new;
+	struct ebitmap_node *node;
+	uint32_t bit;
+	int rc;
 
-	src = pdb->p_type_val_to_name[ft->stype - 1];
 	tgt = pdb->p_type_val_to_name[ft->ttype - 1];
 	class = pdb->p_class_val_to_name[ft->tclass - 1];
 	filename = ft->name;
-	new =  pdb->p_type_val_to_name[datum->otype - 1];
+	do {
+		new = pdb->p_type_val_to_name[datum->otype - 1];
+
+		ebitmap_for_each_positive_bit(&datum->stypes, node, bit) {
+			src = pdb->p_type_val_to_name[bit];
+			rc = strs_create_and_add(strs,
+						 "(typetransition %s %s %s %s %s)",
+						 5, src, tgt, class, filename, new);
+			if (rc)
+				return rc;
+		}
+
+		datum = datum->next;
+	} while (datum);
 
-	return strs_create_and_add(strs, "(typetransition %s %s %s %s %s)", 5,
-				   src, tgt, class, filename, new);
+	return 0;
 }
 
 static int write_filename_trans_rules_to_cil(FILE *out, struct policydb *pdb)
diff --git a/libsepol/src/kernel_to_conf.c b/libsepol/src/kernel_to_conf.c
index 7cc91eb3..62bf706c 100644
--- a/libsepol/src/kernel_to_conf.c
+++ b/libsepol/src/kernel_to_conf.c
@@ -1822,21 +1822,35 @@ struct map_filename_trans_args {
 
 static int map_filename_trans_to_str(hashtab_key_t key, void *data, void *arg)
 {
-	filename_trans_t *ft = (filename_trans_t *)key;
+	filename_trans_key_t *ft = (filename_trans_key_t *)key;
 	filename_trans_datum_t *datum = data;
 	struct map_filename_trans_args *map_args = arg;
 	struct policydb *pdb = map_args->pdb;
 	struct strs *strs = map_args->strs;
 	char *src, *tgt, *class, *filename, *new;
+	struct ebitmap_node *node;
+	uint32_t bit;
+	int rc;
 
-	src = pdb->p_type_val_to_name[ft->stype - 1];
 	tgt = pdb->p_type_val_to_name[ft->ttype - 1];
 	class = pdb->p_class_val_to_name[ft->tclass - 1];
 	filename = ft->name;
-	new =  pdb->p_type_val_to_name[datum->otype - 1];
+	do {
+		new = pdb->p_type_val_to_name[datum->otype - 1];
+
+		ebitmap_for_each_positive_bit(&datum->stypes, node, bit) {
+			src = pdb->p_type_val_to_name[bit];
+			rc = strs_create_and_add(strs,
+						 "type_transition %s %s:%s %s \"%s\";",
+						 5, src, tgt, class, new, filename);
+			if (rc)
+				return rc;
+		}
+
+		datum = datum->next;
+	} while (datum);
 
-	return strs_create_and_add(strs, "type_transition %s %s:%s %s \"%s\";", 5,
-				   src, tgt, class, new, filename);
+	return 0;
 }
 
 static int write_filename_trans_rules_to_conf(FILE *out, struct policydb *pdb)
diff --git a/libsepol/src/policydb.c b/libsepol/src/policydb.c
index 3992ea56..0b98d50b 100644
--- a/libsepol/src/policydb.c
+++ b/libsepol/src/policydb.c
@@ -789,12 +789,12 @@ partial_name_hash(unsigned long c, unsigned long prevhash)
 
 static unsigned int filenametr_hash(hashtab_t h, const_hashtab_key_t k)
 {
-	const struct filename_trans *ft = (const struct filename_trans *)k;
+	const filename_trans_key_t *ft = (const filename_trans_key_t *)k;
 	unsigned long hash;
 	unsigned int byte_num;
 	unsigned char focus;
 
-	hash = ft->stype ^ ft->ttype ^ ft->tclass;
+	hash = ft->ttype ^ ft->tclass;
 
 	byte_num = 0;
 	while ((focus = ft->name[byte_num++]))
@@ -805,14 +805,10 @@ static unsigned int filenametr_hash(hashtab_t h, const_hashtab_key_t k)
 static int filenametr_cmp(hashtab_t h __attribute__ ((unused)),
 			  const_hashtab_key_t k1, const_hashtab_key_t k2)
 {
-	const struct filename_trans *ft1 = (const struct filename_trans *)k1;
-	const struct filename_trans *ft2 = (const struct filename_trans *)k2;
+	const filename_trans_key_t *ft1 = (const filename_trans_key_t *)k1;
+	const filename_trans_key_t *ft2 = (const filename_trans_key_t *)k2;
 	int v;
 
-	v = ft1->stype - ft2->stype;
-	if (v)
-		return v;
-
 	v = ft1->ttype - ft2->ttype;
 	if (v)
 		return v;
@@ -1409,9 +1405,12 @@ common_destroy, class_destroy, role_destroy, type_destroy, user_destroy,
 static int filenametr_destroy(hashtab_key_t key, hashtab_datum_t datum,
 			      void *p __attribute__ ((unused)))
 {
-	struct filename_trans *ft = (struct filename_trans *)key;
+	filename_trans_key_t *ft = (filename_trans_key_t *)key;
+	filename_trans_datum_t *fd = datum;
+
 	free(ft->name);
 	free(key);
+	ebitmap_destroy(&fd->stypes);
 	free(datum);
 	return 0;
 }
@@ -2595,12 +2594,85 @@ int role_allow_read(role_allow_t ** r, struct policy_file *fp)
 	return 0;
 }
 
+int policydb_filetrans_insert(policydb_t *p, uint32_t stype, uint32_t ttype,
+			      uint32_t tclass, const char *name,
+			      char **name_alloc, uint32_t otype,
+			      uint32_t *present_otype)
+{
+	filename_trans_key_t *ft, key;
+	filename_trans_datum_t *datum, *last;
+
+	key.ttype = ttype;
+	key.tclass = tclass;
+	key.name = (char *)name;
+
+	last = NULL;
+	datum = hashtab_search(p->filename_trans, (hashtab_key_t)&key);
+	while (datum) {
+		if (ebitmap_get_bit(&datum->stypes, stype - 1)) {
+			if (present_otype)
+				*present_otype = datum->otype;
+			return SEPOL_EEXIST;
+		}
+		if (datum->otype == otype)
+			break;
+		last = datum;
+		datum = datum->next;
+	}
+	if (!datum) {
+		datum = malloc(sizeof(*datum));
+		if (!datum)
+			return SEPOL_ENOMEM;
+
+		ebitmap_init(&datum->stypes);
+		datum->otype = otype;
+		datum->next = NULL;
+
+		if (last) {
+			last->next = datum;
+		} else {
+			char *name_dup;
+
+			if (name_alloc) {
+				name_dup = *name_alloc;
+				*name_alloc = NULL;
+			} else {
+				name_dup = strdup(name);
+				if (!name_dup) {
+					free(datum);
+					return SEPOL_ENOMEM;
+				}
+			}
+
+			ft = malloc(sizeof(*ft));
+			if (!ft) {
+				free(name_dup);
+				free(datum);
+				return SEPOL_ENOMEM;
+			}
+
+			ft->ttype = ttype;
+			ft->tclass = tclass;
+			ft->name = name_dup;
+
+			if (hashtab_insert(p->filename_trans, (hashtab_key_t)ft,
+					   (hashtab_datum_t)datum)) {
+				free(name_dup);
+				free(datum);
+				free(ft);
+				return SEPOL_ENOMEM;
+			}
+		}
+	}
+
+	p->filename_trans_count++;
+	return ebitmap_set_bit(&datum->stypes, stype - 1, 1);
+}
+
 int filename_trans_read(policydb_t *p, struct policy_file *fp)
 {
 	unsigned int i;
-	uint32_t buf[4], nel, len;
-	filename_trans_t *ft;
-	filename_trans_datum_t *otype;
+	uint32_t buf[4], nel, len, stype, ttype, tclass, otype;
 	int rc;
 	char *name;
 
@@ -2610,16 +2682,8 @@ int filename_trans_read(policydb_t *p, struct policy_file *fp)
 	nel = le32_to_cpu(buf[0]);
 
 	for (i = 0; i < nel; i++) {
-		ft = NULL;
-		otype = NULL;
 		name = NULL;
 
-		ft = calloc(1, sizeof(*ft));
-		if (!ft)
-			goto err;
-		otype = calloc(1, sizeof(*otype));
-		if (!otype)
-			goto err;
 		rc = next_entry(buf, fp, sizeof(uint32_t));
 		if (rc < 0)
 			goto err;
@@ -2631,8 +2695,6 @@ int filename_trans_read(policydb_t *p, struct policy_file *fp)
 		if (!name)
 			goto err;
 
-		ft->name = name;
-
 		rc = next_entry(name, fp, len);
 		if (rc < 0)
 			goto err;
@@ -2641,13 +2703,13 @@ int filename_trans_read(policydb_t *p, struct policy_file *fp)
 		if (rc < 0)
 			goto err;
 
-		ft->stype = le32_to_cpu(buf[0]);
-		ft->ttype = le32_to_cpu(buf[1]);
-		ft->tclass = le32_to_cpu(buf[2]);
-		otype->otype = le32_to_cpu(buf[3]);
+		stype  = le32_to_cpu(buf[0]);
+		ttype  = le32_to_cpu(buf[1]);
+		tclass = le32_to_cpu(buf[2]);
+		otype  = le32_to_cpu(buf[3]);
 
-		rc = hashtab_insert(p->filename_trans, (hashtab_key_t) ft,
-				    otype);
+		rc = policydb_filetrans_insert(p, stype, ttype, tclass, name,
+					       &name, otype, NULL);
 		if (rc) {
 			if (rc != SEPOL_EEXIST)
 				goto err;
@@ -2657,16 +2719,11 @@ int filename_trans_read(policydb_t *p, struct policy_file *fp)
 			 * compatibility, do not reject such policies, just
 			 * ignore the duplicate.
 			 */
-			free(ft);
-			free(name);
-			free(otype);
-			/* continue, ignoring this one */
 		}
+		free(name);
 	}
 	return 0;
 err:
-	free(ft);
-	free(otype);
 	free(name);
 	return -1;
 }
diff --git a/libsepol/src/write.c b/libsepol/src/write.c
index 1fd6a16a..d3aee8d5 100644
--- a/libsepol/src/write.c
+++ b/libsepol/src/write.c
@@ -571,44 +571,50 @@ static int role_allow_write(role_allow_t * r, struct policy_file *fp)
 
 static int filename_write_helper(hashtab_key_t key, void *data, void *ptr)
 {
-	uint32_t buf[4];
+	uint32_t bit, buf[4];
 	size_t items, len;
-	struct filename_trans *ft = (struct filename_trans *)key;
-	struct filename_trans_datum *otype = data;
+	filename_trans_key_t *ft = (filename_trans_key_t *)key;
+	filename_trans_datum_t *datum = data;
+	ebitmap_node_t *node;
 	void *fp = ptr;
 
 	len = strlen(ft->name);
-	buf[0] = cpu_to_le32(len);
-	items = put_entry(buf, sizeof(uint32_t), 1, fp);
-	if (items != 1)
-		return POLICYDB_ERROR;
+	do {
+		ebitmap_for_each_positive_bit(&datum->stypes, node, bit) {
+			buf[0] = cpu_to_le32(len);
+			items = put_entry(buf, sizeof(uint32_t), 1, fp);
+			if (items != 1)
+				return POLICYDB_ERROR;
 
-	items = put_entry(ft->name, sizeof(char), len, fp);
-	if (items != len)
-		return POLICYDB_ERROR;
+			items = put_entry(ft->name, sizeof(char), len, fp);
+			if (items != len)
+				return POLICYDB_ERROR;
 
-	buf[0] = cpu_to_le32(ft->stype);
-	buf[1] = cpu_to_le32(ft->ttype);
-	buf[2] = cpu_to_le32(ft->tclass);
-	buf[3] = cpu_to_le32(otype->otype);
-	items = put_entry(buf, sizeof(uint32_t), 4, fp);
-	if (items != 4)
-		return POLICYDB_ERROR;
+			buf[0] = cpu_to_le32(bit + 1);
+			buf[1] = cpu_to_le32(ft->ttype);
+			buf[2] = cpu_to_le32(ft->tclass);
+			buf[3] = cpu_to_le32(datum->otype);
+			items = put_entry(buf, sizeof(uint32_t), 4, fp);
+			if (items != 4)
+				return POLICYDB_ERROR;
+		}
+
+		datum = datum->next;
+	} while (datum);
 
 	return 0;
 }
 
 static int filename_trans_write(struct policydb *p, void *fp)
 {
-	size_t nel, items;
+	size_t items;
 	uint32_t buf[1];
 	int rc;
 
 	if (p->policyvers < POLICYDB_VERSION_FILENAME_TRANS)
 		return 0;
 
-	nel =  p->filename_trans->nel;
-	buf[0] = cpu_to_le32(nel);
+	buf[0] = cpu_to_le32(p->filename_trans_count);
 	items = put_entry(buf, sizeof(uint32_t), 1, fp);
 	if (items != 1)
 		return POLICYDB_ERROR;
-- 
2.26.2

[PATCH v6 2/2] libsepol: implement POLICYDB_VERSION_COMP_FTRANS

[Ondrej Mosnacek]

Implement a new, more space-efficient form of storing filename
transitions in the binary policy. The internal structures have already
been converted to this new representation; this patch just implements
reading/writing an equivalent representation from/to the binary policy.

This new format reduces the size of Fedora policy from 7.6 MB to only
3.3 MB (with policy optimization enabled in both cases). With the
unconfined module disabled, the size is reduced from 3.3 MB to 2.4 MB.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
---
 libsepol/include/sepol/policydb/policydb.h |   3 +-
 libsepol/src/policydb.c                    | 209 +++++++++++++++++----
 libsepol/src/write.c                       |  73 ++++++-
 3 files changed, 242 insertions(+), 43 deletions(-)

diff --git a/libsepol/include/sepol/policydb/policydb.h b/libsepol/include/sepol/policydb/policydb.h
index c3180c61..9ef43abc 100644
--- a/libsepol/include/sepol/policydb/policydb.h
+++ b/libsepol/include/sepol/policydb/policydb.h
@@ -755,10 +755,11 @@ extern int policydb_set_target_platform(policydb_t *p, int platform);
 #define POLICYDB_VERSION_XPERMS_IOCTL	30 /* Linux-specific */
 #define POLICYDB_VERSION_INFINIBAND		31 /* Linux-specific */
 #define POLICYDB_VERSION_GLBLUB		32
+#define POLICYDB_VERSION_COMP_FTRANS	33 /* compressed filename transitions */
 
 /* Range of policy versions we understand*/
 #define POLICYDB_VERSION_MIN	POLICYDB_VERSION_BASE
-#define POLICYDB_VERSION_MAX	POLICYDB_VERSION_GLBLUB
+#define POLICYDB_VERSION_MAX	POLICYDB_VERSION_COMP_FTRANS
 
 /* Module versions and specific changes*/
 #define MOD_POLICYDB_VERSION_BASE		4
diff --git a/libsepol/src/policydb.c b/libsepol/src/policydb.c
index 0b98d50b..ce8f3ad7 100644
--- a/libsepol/src/policydb.c
+++ b/libsepol/src/policydb.c
@@ -200,6 +200,13 @@ static struct policydb_compat_info policydb_compat[] = {
 	 .ocon_num = OCON_IBENDPORT + 1,
 	 .target_platform = SEPOL_TARGET_SELINUX,
 	},
+	{
+	 .type = POLICY_KERN,
+	 .version = POLICYDB_VERSION_COMP_FTRANS,
+	 .sym_num = SYM_NUM,
+	 .ocon_num = OCON_IBENDPORT + 1,
+	 .target_platform = SEPOL_TARGET_SELINUX,
+	},
 	{
 	 .type = POLICY_BASE,
 	 .version = MOD_POLICYDB_VERSION_BASE,
@@ -2669,65 +2676,201 @@ int policydb_filetrans_insert(policydb_t *p, uint32_t stype, uint32_t ttype,
 	return ebitmap_set_bit(&datum->stypes, stype - 1, 1);
 }
 
-int filename_trans_read(policydb_t *p, struct policy_file *fp)
+static int filename_trans_read_one_compat(policydb_t *p, struct policy_file *fp)
 {
-	unsigned int i;
-	uint32_t buf[4], nel, len, stype, ttype, tclass, otype;
+	uint32_t buf[4], len, stype, ttype, tclass, otype;
+	char *name = NULL;
 	int rc;
-	char *name;
 
 	rc = next_entry(buf, fp, sizeof(uint32_t));
 	if (rc < 0)
 		return -1;
-	nel = le32_to_cpu(buf[0]);
+	len = le32_to_cpu(buf[0]);
+	if (zero_or_saturated(len))
+		return -1;
 
-	for (i = 0; i < nel; i++) {
-		name = NULL;
+	name = calloc(len + 1, sizeof(*name));
+	if (!name)
+		return -1;
 
-		rc = next_entry(buf, fp, sizeof(uint32_t));
-		if (rc < 0)
-			goto err;
-		len = le32_to_cpu(buf[0]);
-		if (zero_or_saturated(len))
+	rc = next_entry(name, fp, len);
+	if (rc < 0)
+		goto err;
+
+	rc = next_entry(buf, fp, sizeof(uint32_t) * 4);
+	if (rc < 0)
+		goto err;
+
+	stype  = le32_to_cpu(buf[0]);
+	ttype  = le32_to_cpu(buf[1]);
+	tclass = le32_to_cpu(buf[2]);
+	otype  = le32_to_cpu(buf[3]);
+
+	rc = policydb_filetrans_insert(p, stype, ttype, tclass, name, &name,
+				       otype, NULL);
+	if (rc) {
+		if (rc != SEPOL_EEXIST)
 			goto err;
+		/*
+		 * Some old policies were wrongly generated with
+		 * duplicate filename transition rules.  For backward
+		 * compatibility, do not reject such policies, just
+		 * ignore the duplicate.
+		 */
+	}
+	free(name);
+	return 0;
+err:
+	free(name);
+	return -1;
+}
+
+static int filename_trans_check_datum(filename_trans_datum_t *datum)
+{
+	ebitmap_t stypes, otypes;
+	int rc = -1;
+
+	ebitmap_init(&stypes);
+	ebitmap_init(&otypes);
+
+	while (datum) {
+		if (ebitmap_get_bit(&otypes, datum->otype))
+			goto out;
+
+		if (ebitmap_set_bit(&otypes, datum->otype, 1))
+			goto out;
+
+		if (ebitmap_match_any(&stypes, &datum->stypes))
+			goto out;
 
-		name = calloc(len + 1, sizeof(*name));
-		if (!name)
+		if (ebitmap_union(&stypes, &datum->stypes))
+			goto out;
+
+		datum = datum->next;
+	}
+	rc = 0;
+out:
+	ebitmap_destroy(&stypes);
+	ebitmap_destroy(&otypes);
+	return rc;
+}
+
+static int filename_trans_read_one(policydb_t *p, struct policy_file *fp)
+{
+	filename_trans_key_t *ft = NULL;
+	filename_trans_datum_t **dst, *datum, *first = NULL;
+	unsigned int i;
+	uint32_t buf[3], len, ttype, tclass, ndatum;
+	char *name = NULL;
+	int rc;
+
+	rc = next_entry(buf, fp, sizeof(uint32_t));
+	if (rc < 0)
+		return -1;
+	len = le32_to_cpu(buf[0]);
+	if (zero_or_saturated(len))
+		return -1;
+
+	name = calloc(len + 1, sizeof(*name));
+	if (!name)
+		return -1;
+
+	rc = next_entry(name, fp, len);
+	if (rc < 0)
+		goto err;
+
+	rc = next_entry(buf, fp, sizeof(uint32_t) * 3);
+	if (rc < 0)
+		goto err;
+
+	ttype = le32_to_cpu(buf[0]);
+	tclass = le32_to_cpu(buf[1]);
+	ndatum = le32_to_cpu(buf[2]);
+	if (ndatum == 0)
+		goto err;
+
+	dst = &first;
+	for (i = 0; i < ndatum; i++) {
+		datum = malloc(sizeof(*datum));
+		if (!datum)
 			goto err;
 
-		rc = next_entry(name, fp, len);
+		*dst = datum;
+
+		/* ebitmap_read() will at least init the bitmap */
+		rc = ebitmap_read(&datum->stypes, fp);
 		if (rc < 0)
 			goto err;
 
-		rc = next_entry(buf, fp, sizeof(uint32_t) * 4);
+		rc = next_entry(buf, fp, sizeof(uint32_t));
 		if (rc < 0)
 			goto err;
 
-		stype  = le32_to_cpu(buf[0]);
-		ttype  = le32_to_cpu(buf[1]);
-		tclass = le32_to_cpu(buf[2]);
-		otype  = le32_to_cpu(buf[3]);
+		datum->otype = le32_to_cpu(buf[0]);
 
-		rc = policydb_filetrans_insert(p, stype, ttype, tclass, name,
-					       &name, otype, NULL);
-		if (rc) {
-			if (rc != SEPOL_EEXIST)
-				goto err;
-			/*
-			 * Some old policies were wrongly generated with
-			 * duplicate filename transition rules.  For backward
-			 * compatibility, do not reject such policies, just
-			 * ignore the duplicate.
-			 */
-		}
-		free(name);
+		p->filename_trans_count += ebitmap_cardinality(&datum->stypes);
+
+		dst = &datum->next;
 	}
+	*dst = NULL;
+
+	if (ndatum > 1 && filename_trans_check_datum(first))
+		goto err;
+
+	ft = malloc(sizeof(*ft));
+	if (!ft)
+		goto err;
+
+	ft->ttype = ttype;
+	ft->tclass = tclass;
+	ft->name = name;
+
+	rc = hashtab_insert(p->filename_trans, (hashtab_key_t)ft,
+			    (hashtab_datum_t)first);
+	if (rc)
+		goto err;
+
 	return 0;
 err:
+	free(ft);
 	free(name);
+	while (first) {
+		datum = first;
+		first = first->next;
+
+		ebitmap_destroy(&datum->stypes);
+		free(datum);
+	}
 	return -1;
 }
 
+int filename_trans_read(policydb_t *p, struct policy_file *fp)
+{
+	unsigned int i;
+	uint32_t buf[1], nel;
+	int rc;
+
+	rc = next_entry(buf, fp, sizeof(uint32_t));
+	if (rc < 0)
+		return -1;
+	nel = le32_to_cpu(buf[0]);
+
+	if (p->policyvers < POLICYDB_VERSION_COMP_FTRANS) {
+		for (i = 0; i < nel; i++) {
+			rc = filename_trans_read_one_compat(p, fp);
+			if (rc < 0)
+				return -1;
+		}
+	} else {
+		for (i = 0; i < nel; i++) {
+			rc = filename_trans_read_one(p, fp);
+			if (rc < 0)
+				return -1;
+		}
+	}
+	return 0;
+}
+
 static int ocontext_read_xen(struct policydb_compat_info *info,
 	policydb_t *p, struct policy_file *fp)
 {
diff --git a/libsepol/src/write.c b/libsepol/src/write.c
index d3aee8d5..84bcaf3f 100644
--- a/libsepol/src/write.c
+++ b/libsepol/src/write.c
@@ -569,7 +569,7 @@ static int role_allow_write(role_allow_t * r, struct policy_file *fp)
 	return POLICYDB_SUCCESS;
 }
 
-static int filename_write_helper(hashtab_key_t key, void *data, void *ptr)
+static int filename_write_one_compat(hashtab_key_t key, void *data, void *ptr)
 {
 	uint32_t bit, buf[4];
 	size_t items, len;
@@ -605,6 +605,54 @@ static int filename_write_helper(hashtab_key_t key, void *data, void *ptr)
 	return 0;
 }
 
+static int filename_write_one(hashtab_key_t key, void *data, void *ptr)
+{
+	uint32_t buf[3];
+	size_t items, len, ndatum;
+	filename_trans_key_t *ft = (filename_trans_key_t *)key;
+	filename_trans_datum_t *datum;
+	void *fp = ptr;
+
+	len = strlen(ft->name);
+	buf[0] = cpu_to_le32(len);
+	items = put_entry(buf, sizeof(uint32_t), 1, fp);
+	if (items != 1)
+		return POLICYDB_ERROR;
+
+	items = put_entry(ft->name, sizeof(char), len, fp);
+	if (items != len)
+		return POLICYDB_ERROR;
+
+	ndatum = 0;
+	datum = data;
+	do {
+		ndatum++;
+		datum = datum->next;
+	} while (datum);
+
+	buf[0] = cpu_to_le32(ft->ttype);
+	buf[1] = cpu_to_le32(ft->tclass);
+	buf[2] = cpu_to_le32(ndatum);
+	items = put_entry(buf, sizeof(uint32_t), 3, fp);
+	if (items != 3)
+		return POLICYDB_ERROR;
+
+	datum = data;
+	do {
+		if (ebitmap_write(&datum->stypes, fp))
+			return POLICYDB_ERROR;
+
+		buf[0] = cpu_to_le32(datum->otype);
+		items = put_entry(buf, sizeof(uint32_t), 1, fp);
+		if (items != 1)
+			return POLICYDB_ERROR;
+
+		datum = datum->next;
+	} while (datum);
+
+	return 0;
+}
+
 static int filename_trans_write(struct policydb *p, void *fp)
 {
 	size_t items;
@@ -614,16 +662,23 @@ static int filename_trans_write(struct policydb *p, void *fp)
 	if (p->policyvers < POLICYDB_VERSION_FILENAME_TRANS)
 		return 0;
 
-	buf[0] = cpu_to_le32(p->filename_trans_count);
-	items = put_entry(buf, sizeof(uint32_t), 1, fp);
-	if (items != 1)
-		return POLICYDB_ERROR;
+	if (p->policyvers < POLICYDB_VERSION_COMP_FTRANS) {
+		buf[0] = cpu_to_le32(p->filename_trans_count);
+		items = put_entry(buf, sizeof(uint32_t), 1, fp);
+		if (items != 1)
+			return POLICYDB_ERROR;
 
-	rc = hashtab_map(p->filename_trans, filename_write_helper, fp);
-	if (rc)
-		return rc;
+		rc = hashtab_map(p->filename_trans, filename_write_one_compat,
+				 fp);
+	} else {
+		buf[0] = cpu_to_le32(p->filename_trans->nel);
+		items = put_entry(buf, sizeof(uint32_t), 1, fp);
+		if (items != 1)
+			return POLICYDB_ERROR;
 
-	return 0;
+		rc = hashtab_map(p->filename_trans, filename_write_one, fp);
+	}
+	return rc;
 }
 
 static int role_set_write(role_set_t * x, struct policy_file *fp)
-- 
2.26.2

Re: [PATCH v6 1/2] libsepol,checkpolicy: optimize storage of filename transitions

[Stephen Smalley]

On 7/31/20 7:10 AM, Ondrej Mosnacek wrote:

> In preparation to support a new policy format with a more optimal
> representation of filename transition rules, this patch applies an
> equivalent change from kernel commit c3a276111ea2 ("selinux: optimize
> storage of filename transitions").
>
> See the kernel commit's description [1] for the rationale behind this
> representation. This change doesn't bring any measurable difference of
> policy build performance (semodule -B) on Fedora.
>
> [1] https://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux.git/commit/?id=c3a276111ea2572399281988b3129683e2a6b60b
>
> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>

Re: [PATCH v6 2/2] libsepol: implement POLICYDB_VERSION_COMP_FTRANS

[Stephen Smalley]

On 7/31/20 7:10 AM, Ondrej Mosnacek wrote:

> Implement a new, more space-efficient form of storing filename
> transitions in the binary policy. The internal structures have already
> been converted to this new representation; this patch just implements
> reading/writing an equivalent representation from/to the binary policy.
>
> This new format reduces the size of Fedora policy from 7.6 MB to only
> 3.3 MB (with policy optimization enabled in both cases). With the
> unconfined module disabled, the size is reduced from 3.3 MB to 2.4 MB.
>
> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>

Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>

Re: [PATCH v6 1/2] libsepol,checkpolicy: optimize storage of filename transitions

[Stephen Smalley]

On 8/3/20 9:56 AM, Stephen Smalley wrote:

> On 7/31/20 7:10 AM, Ondrej Mosnacek wrote:
>
>> In preparation to support a new policy format with a more optimal
>> representation of filename transition rules, this patch applies an
>> equivalent change from kernel commit c3a276111ea2 ("selinux: optimize
>> storage of filename transitions").
>>
>> See the kernel commit's description [1] for the rationale behind this
>> representation. This change doesn't bring any measurable difference of
>> policy build performance (semodule -B) on Fedora.
>>
>> [1] 
>> https://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux.git/commit/?id=c3a276111ea2572399281988b3129683e2a6b60b
>>
>> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
> Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Thanks, applied.

Re: [PATCH v6 2/2] libsepol: implement POLICYDB_VERSION_COMP_FTRANS

[Stephen Smalley]

On 8/3/20 9:57 AM, Stephen Smalley wrote:

> On 7/31/20 7:10 AM, Ondrej Mosnacek wrote:
>
>> Implement a new, more space-efficient form of storing filename
>> transitions in the binary policy. The internal structures have already
>> been converted to this new representation; this patch just implements
>> reading/writing an equivalent representation from/to the binary policy.
>>
>> This new format reduces the size of Fedora policy from 7.6 MB to only
>> 3.3 MB (with policy optimization enabled in both cases). With the
>> unconfined module disabled, the size is reduced from 3.3 MB to 2.4 MB.
>>
>> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
>
> Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
>
Thanks, applied.