libsepol/libsepol-rhat.patch

diff --git a/libsepol/include/sepol/handle.h b/libsepol/include/sepol/handle.h
index 19be326..115bda1 100644
--- a/libsepol/include/sepol/handle.h
+++ b/libsepol/include/sepol/handle.h
@@ -24,4 +24,11 @@ void sepol_set_expand_consume_base(sepol_handle_t * sh, int consume_base);
 /* Destroy a sepol handle. */
 void sepol_handle_destroy(sepol_handle_t *);
 
+/* Get whether or not needless unused branch of tunables would be preserved */
+int sepol_get_preserve_tunables(sepol_handle_t * sh);
+
+/* Set whether or not to preserve the needless unused branch of tunables,
+ * 0 is default and discard such branch, 1 preserves them */
+void sepol_set_preserve_tunables(sepol_handle_t * sh, int preserve_tunables);
+
 #endif
diff --git a/libsepol/include/sepol/policydb/conditional.h b/libsepol/include/sepol/policydb/conditional.h
index a8ed694..48ec106 100644
--- a/libsepol/include/sepol/policydb/conditional.h
+++ b/libsepol/include/sepol/policydb/conditional.h
@@ -77,15 +77,17 @@ typedef struct cond_node {
 	/* these true/false lists point into te_avtab when that is used */
 	cond_av_list_t *true_list;
 	cond_av_list_t *false_list;
-	/* and these are using during parsing and for modules */
+	/* and these are used during parsing and for modules */
 	avrule_t *avtrue_list;
 	avrule_t *avfalse_list;
 	/* these fields are not written to binary policy */
 	unsigned int nbools;
 	uint32_t bool_ids[COND_MAX_BOOLS];
 	uint32_t expr_pre_comp;
-	/*                                               */
 	struct cond_node *next;
+	/* a tunable conditional, calculated and used at expansion */
+#define	COND_NODE_FLAGS_TUNABLE	0x01
+	uint32_t flags;
 } cond_node_t;
 
 extern int cond_evaluate_expr(policydb_t * p, cond_expr_t * expr);
diff --git a/libsepol/include/sepol/policydb/policydb.h b/libsepol/include/sepol/policydb/policydb.h
index 5320bc8..1848a7b 100644
--- a/libsepol/include/sepol/policydb/policydb.h
+++ b/libsepol/include/sepol/policydb/policydb.h
@@ -210,6 +210,8 @@ typedef struct range_trans {
 typedef struct cond_bool_datum {
 	symtab_datum_t s;
 	int state;
+#define COND_BOOL_FLAGS_TUNABLE	0x01	/* is this a tunable? */
+	uint32_t flags;
 } cond_bool_datum_t;
 
 struct cond_node;
@@ -683,9 +685,10 @@ extern int policydb_set_target_platform(policydb_t *p, int platform);
 #define MOD_POLICYDB_VERSION_FILENAME_TRANS	11
 #define MOD_POLICYDB_VERSION_ROLETRANS		12
 #define MOD_POLICYDB_VERSION_ROLEATTRIB		13
+#define MOD_POLICYDB_VERSION_TUNABLE_SEP	14
 
 #define MOD_POLICYDB_VERSION_MIN MOD_POLICYDB_VERSION_BASE
-#define MOD_POLICYDB_VERSION_MAX MOD_POLICYDB_VERSION_ROLEATTRIB
+#define MOD_POLICYDB_VERSION_MAX MOD_POLICYDB_VERSION_TUNABLE_SEP
 
 #define POLICYDB_CONFIG_MLS    1
 
diff --git a/libsepol/src/conditional.c b/libsepol/src/conditional.c
index 1482387..ea47cdd 100644
--- a/libsepol/src/conditional.c
+++ b/libsepol/src/conditional.c
@@ -160,6 +160,7 @@ cond_node_t *cond_node_create(policydb_t * p, cond_node_t * node)
 		for (i = 0; i < min(node->nbools, COND_MAX_BOOLS); i++)
 			new_node->bool_ids[i] = node->bool_ids[i];
 		new_node->expr_pre_comp = node->expr_pre_comp;
+		new_node->flags = node->flags;
 	}
 
 	return new_node;
@@ -563,8 +564,8 @@ static int bool_isvalid(cond_bool_datum_t * b)
 	return 1;
 }
 
-int cond_read_bool(policydb_t * p
-		   __attribute__ ((unused)), hashtab_t h,
+int cond_read_bool(policydb_t * p,
+		   hashtab_t h,
 		   struct policy_file *fp)
 {
 	char *key = 0;
@@ -596,6 +597,15 @@ int cond_read_bool(policydb_t * p
 	if (rc < 0)
 		goto err;
 	key[len] = 0;
+
+	if (p->policy_type != POLICY_KERN &&
+	    p->policyvers >= MOD_POLICYDB_VERSION_TUNABLE_SEP) {
+		rc = next_entry(buf, fp, sizeof(uint32_t));
+		if (rc < 0)
+			goto err;
+		booldatum->flags = le32_to_cpu(buf[0]);
+	}
+
 	if (hashtab_insert(h, key, booldatum))
 		goto err;
 
@@ -810,6 +820,14 @@ static int cond_read_node(policydb_t * p, cond_node_t * node, void *fp)
 			goto err;
 	}
 
+	if (p->policy_type != POLICY_KERN &&
+	    p->policyvers >= MOD_POLICYDB_VERSION_TUNABLE_SEP) {
+		rc = next_entry(buf, fp, sizeof(uint32_t));
+		if (rc < 0)
+			goto err;
+		node->flags = le32_to_cpu(buf[0]);
+	}
+
 	return 0;
       err:
 	cond_node_destroy(node);
diff --git a/libsepol/src/expand.c b/libsepol/src/expand.c
index 06f11f4..2861776 100644
--- a/libsepol/src/expand.c
+++ b/libsepol/src/expand.c
@@ -1014,6 +1014,11 @@ static int bool_copy_callback(hashtab_key_t key, hashtab_datum_t datum,
 		return 0;
 	}
 
+	if (bool->flags & COND_BOOL_FLAGS_TUNABLE) {
+		/* Skip tunables */
+		return 0;
+	}
+
 	if (state->verbose)
 		INFO(state->handle, "copying boolean %s", id);
 
@@ -1046,6 +1051,7 @@ static int bool_copy_callback(hashtab_key_t key, hashtab_datum_t datum,
 	state->boolmap[bool->s.value - 1] = new_bool->s.value;
 
 	new_bool->state = bool->state;
+	new_bool->flags = bool->flags;
 
 	return 0;
 }
@@ -1940,6 +1946,13 @@ static int cond_node_copy(expand_state_t * state, cond_node_t * cn)
 	if (cond_node_copy(state, cn->next)) {
 		return -1;
 	}
+
+	/* If current cond_node_t is of tunable, its effective branch
+	 * has been appended to its home decl->avrules list during link
+	 * and now we should just skip it. */
+	if (cn->flags & COND_NODE_FLAGS_TUNABLE)
+		return 0;
+
 	if (cond_normalize_expr(state->base, cn)) {
 		ERR(state->handle, "Error while normalizing conditional");
 		return -1;
@@ -2665,6 +2678,106 @@ int expand_module_avrules(sepol_handle_t * handle, policydb_t * base,
 	return copy_and_expand_avrule_block(&state);
 }
 
+static void discard_tunables(sepol_handle_t *sh, policydb_t *pol)
+{
+	avrule_block_t *block;
+	avrule_decl_t *decl;
+	cond_node_t *cur_node;
+	cond_expr_t *cur_expr;
+	int cur_state, preserve_tunables = 0;
+	avrule_t *tail, *to_be_appended;
+
+	if (sh && sh->preserve_tunables)
+		preserve_tunables = 1;
+
+	/* Iterate through all cond_node of all enabled decls, if a cond_node
+	 * is about tunable, calculate its state value and concatenate one of
+	 * its avrule list to the current decl->avrules list. On the other
+	 * hand, the disabled unused branch of a tunable would be discarded.
+	 *
+	 * Note, such tunable cond_node would be skipped over in expansion,
+	 * so we won't have to worry about removing it from decl->cond_list
+	 * here :-)
+	 *
+	 * If tunables are requested to be preserved then they would be
+	 * "transformed" as booleans by having their TUNABLE flag cleared.
+	 */
+	for (block = pol->global; block != NULL; block = block->next) {
+		decl = block->enabled;
+		if (decl == NULL || decl->enabled == 0)
+			continue;
+
+		tail = decl->avrules;
+		while (tail && tail->next)
+			tail = tail->next;
+
+		for (cur_node = decl->cond_list; cur_node != NULL;
+		     cur_node = cur_node->next) {
+			int booleans, tunables, i;
+			cond_bool_datum_t *booldatum;
+			cond_bool_datum_t *tmp[COND_EXPR_MAXDEPTH];
+
+			booleans = tunables = 0;
+			memset(tmp, 0, sizeof(cond_bool_datum_t *) * COND_EXPR_MAXDEPTH);
+
+			for (cur_expr = cur_node->expr; cur_expr != NULL;
+			     cur_expr = cur_expr->next) {
+				if (cur_expr->expr_type != COND_BOOL)
+					continue;
+				booldatum = pol->bool_val_to_struct[cur_expr->bool - 1];
+				if (booldatum->flags & COND_BOOL_FLAGS_TUNABLE)
+					tmp[tunables++] = booldatum;
+				else
+					booleans++;
+			}
+
+			/* bool_copy_callback() at link phase has ensured
+			 * that no mixture of tunables and booleans in one
+			 * expression. However, this would be broken by the
+			 * request to preserve tunables */
+			if (!preserve_tunables)
+				assert(!(booleans && tunables));
+
+			if (booleans || preserve_tunables) {
+				cur_node->flags &= ~COND_NODE_FLAGS_TUNABLE;
+				if (tunables) {
+					for (i = 0; i < tunables; i++)
+						tmp[i]->flags &= ~COND_BOOL_FLAGS_TUNABLE;
+				}
+			} else {
+				cur_node->flags |= COND_NODE_FLAGS_TUNABLE;
+				cur_state = cond_evaluate_expr(pol, cur_node->expr);
+				if (cur_state == -1) {
+					printf("Expression result was "
+					       "undefined, skipping all"
+					       "rules\n");
+					continue;
+				}
+
+				to_be_appended = (cur_state == 1) ?
+					cur_node->avtrue_list : cur_node->avfalse_list;
+
+				if (tail)
+					tail->next = to_be_appended;
+				else
+					tail = decl->avrules = to_be_appended;
+
+				/* Now that the effective branch has been
+				 * appended, neutralize its original pointer */
+				if (cur_state == 1)
+					cur_node->avtrue_list = NULL;
+				else
+					cur_node->avfalse_list = NULL;
+
+				/* Update the tail of decl->avrules for
+				 * further concatenation */
+				while (tail && tail->next)
+					tail = tail->next;
+			}
+		}
+	}
+}
+
 /* Linking should always be done before calling expand, even if
  * there is only a base since all optionals are dealt with at link time
  * the base passed in should be indexed and avrule blocks should be 
@@ -2678,6 +2791,16 @@ int expand_module(sepol_handle_t * handle,
 	expand_state_t state;
 	avrule_block_t *curblock;
 
+	/* Append tunable's avtrue_list or avfalse_list to the avrules list
+	 * of its home decl depending on its state value, so that the effect
+	 * rules of a tunable would be added to te_avtab permanently. Whereas
+	 * the disabled unused branch would be discarded.
+	 *
+	 * Originally this function is called at the very end of link phase,
+	 * however, we need to keep the linked policy intact for analysis
+	 * purpose. */
+	discard_tunables(handle, base);
+
 	expand_state_init(&state);
 
 	state.verbose = verbose;
diff --git a/libsepol/src/handle.c b/libsepol/src/handle.c
index 191ac57..2e9a4ad 100644
--- a/libsepol/src/handle.c
+++ b/libsepol/src/handle.c
@@ -18,9 +18,24 @@ sepol_handle_t *sepol_handle_create(void)
 	sh->disable_dontaudit = 0;
 	sh->expand_consume_base = 0;
 
+	/* by default needless unused branch of tunables would be discarded  */
+	sh->preserve_tunables = 0;
+
 	return sh;
 }
 
+int sepol_get_preserve_tunables(sepol_handle_t *sh)
+{
+	assert(sh != NULL);
+	return sh->preserve_tunables;
+}
+
+void sepol_set_preserve_tunables(sepol_handle_t * sh, int preserve_tunables)
+{
+	assert(sh !=NULL);
+	sh->preserve_tunables = preserve_tunables;
+}
+
 int sepol_get_disable_dontaudit(sepol_handle_t *sh)
 {
 	assert(sh !=NULL);
diff --git a/libsepol/src/handle.h b/libsepol/src/handle.h
index 254fbd8..7728d04 100644
--- a/libsepol/src/handle.h
+++ b/libsepol/src/handle.h
@@ -17,7 +17,7 @@ struct sepol_handle {
 
 	int disable_dontaudit;
 	int expand_consume_base;
-
+	int preserve_tunables;
 };
 
 #endif
diff --git a/libsepol/src/libsepol.map b/libsepol/src/libsepol.map
index 719e5b7..c6bb788 100644
--- a/libsepol/src/libsepol.map
+++ b/libsepol/src/libsepol.map
@@ -1,5 +1,6 @@
 {
   global: 
+	expand_module_avrules;
 	sepol_module_package_*; sepol_link_modules; sepol_expand_module; sepol_link_packages;
 	sepol_bool_*; sepol_genbools*; 
 	sepol_context_*; sepol_mls_*; sepol_check_context;
@@ -15,5 +16,6 @@
 	sepol_get_disable_dontaudit;
 	sepol_set_disable_dontaudit;
 	sepol_set_expand_consume_base;
+	sepol_get_preserve_tunables; sepol_set_preserve_tunables;
   local: *;
 };
diff --git a/libsepol/src/link.c b/libsepol/src/link.c
index 421c47b..ee9675b 100644
--- a/libsepol/src/link.c
+++ b/libsepol/src/link.c
@@ -587,7 +587,18 @@ static int bool_copy_callback(hashtab_key_t key, hashtab_datum_t datum,
 		}
 		state->base->p_bools.nprim++;
 		base_bool = new_bool;
-
+		base_bool->flags = booldatum->flags;
+	} else if ((booldatum->flags & COND_BOOL_FLAGS_TUNABLE) !=
+		   (base_bool->flags & COND_BOOL_FLAGS_TUNABLE)) {
+			/* A mismatch between boolean/tunable declaration
+			 * and usage(for example a boolean used in the
+			 * tunable_policy() or vice versa).
+			 *
+			 * This is not allowed and bail out with errors */
+			ERR(state->handle,
+			    "%s: Mismatch between boolean/tunable definition "
+			    "and usage for %s", state->cur_mod_name, id);
+			return -1;
 	}
 
 	/* Get the scope info for this boolean to see if this is the declaration, 
@@ -595,9 +606,12 @@ static int bool_copy_callback(hashtab_key_t key, hashtab_datum_t datum,
 	scope = hashtab_search(state->cur->policy->p_bools_scope.table, id);
 	if (!scope)
 		return SEPOL_ERR;
-	if (scope->scope == SCOPE_DECL)  
+	if (scope->scope == SCOPE_DECL) {
 		base_bool->state = booldatum->state;
-
+		/* Only the declaration rather than requirement
+		 * decides if it is a boolean or tunable. */
+		base_bool->flags = booldatum->flags;
+	}
 	state->cur->map[SYM_BOOLS][booldatum->s.value - 1] = base_bool->s.value;
 	return 0;
 
diff --git a/libsepol/src/policydb.c b/libsepol/src/policydb.c
index 017aeca..136b450 100644
--- a/libsepol/src/policydb.c
+++ b/libsepol/src/policydb.c
@@ -221,6 +221,13 @@ static struct policydb_compat_info policydb_compat[] = {
 	 .target_platform = SEPOL_TARGET_SELINUX,
 	},
 	{
+	 .type = POLICY_BASE,
+	 .version = MOD_POLICYDB_VERSION_TUNABLE_SEP,
+	 .sym_num = SYM_NUM,
+	 .ocon_num = OCON_NODE6 + 1,
+	 .target_platform = SEPOL_TARGET_SELINUX,
+	},
+	{
 	 .type = POLICY_MOD,
 	 .version = MOD_POLICYDB_VERSION_BASE,
 	 .sym_num = SYM_NUM,
@@ -290,6 +297,13 @@ static struct policydb_compat_info policydb_compat[] = {
 	 .ocon_num = 0,
 	 .target_platform = SEPOL_TARGET_SELINUX,
 	},
+	{
+	 .type = POLICY_MOD,
+	 .version = MOD_POLICYDB_VERSION_TUNABLE_SEP,
+	 .sym_num = SYM_NUM,
+	 .ocon_num = 0,
+	 .target_platform = SEPOL_TARGET_SELINUX,
+	},
 };
 
 #if 0
diff --git a/libsepol/src/write.c b/libsepol/src/write.c
index 290e036..e34ab52 100644
--- a/libsepol/src/write.c
+++ b/libsepol/src/write.c
@@ -607,6 +607,7 @@ static int cond_write_bool(hashtab_key_t key, hashtab_datum_t datum, void *ptr)
 	unsigned int items, items2;
 	struct policy_data *pd = ptr;
 	struct policy_file *fp = pd->fp;
+	struct policydb *p = pd->p;
 
 	booldatum = (cond_bool_datum_t *) datum;
 
@@ -621,6 +622,15 @@ static int cond_write_bool(hashtab_key_t key, hashtab_datum_t datum, void *ptr)
 	items = put_entry(key, 1, len, fp);
 	if (items != len)
 		return POLICYDB_ERROR;
+
+	if (p->policy_type != POLICY_KERN &&
+	    p->policyvers >= MOD_POLICYDB_VERSION_TUNABLE_SEP) {
+		buf[0] = cpu_to_le32(booldatum->flags);
+		items = put_entry(buf, sizeof(uint32_t), 1, fp);
+		if (items != 1)
+			return POLICYDB_ERROR;
+	}
+
 	return POLICYDB_SUCCESS;
 }
 
@@ -727,6 +737,14 @@ static int cond_write_node(policydb_t * p,
 			return POLICYDB_ERROR;
 	}
 
+	if (p->policy_type != POLICY_KERN &&
+	    p->policyvers >= MOD_POLICYDB_VERSION_TUNABLE_SEP) {
+		buf[0] = cpu_to_le32(node->flags);
+		items = put_entry(buf, sizeof(uint32_t), 1, fp);
+		if (items != 1)
+			return POLICYDB_ERROR;
+	}
+
 	return POLICYDB_SUCCESS;
 }
 
@@ -972,6 +990,19 @@ static int role_write(hashtab_key_t key, hashtab_datum_t datum, void *ptr)
 
 	role = (role_datum_t *) datum;
 
+	/*
+	 * Role attributes are redundant for policy.X, skip them
+	 * when writing the roles symbol table. They are also skipped
+	 * when pp is downgraded.
+	 *
+	 * Their numbers would be deducted in policydb_write().
+	 */
+	if ((role->flavor == ROLE_ATTRIB) &&
+	    ((p->policy_type == POLICY_KERN) ||
+	     (p->policy_type != POLICY_KERN &&
+	      p->policyvers < MOD_POLICYDB_VERSION_ROLEATTRIB)))
+		return POLICYDB_SUCCESS;
+
 	len = strlen(key);
 	items = 0;
 	buf[items++] = cpu_to_le32(len);
@@ -1795,6 +1826,19 @@ static int type_attr_uncount(hashtab_key_t key __attribute__ ((unused)),
 	return 0;
 }
 
+static int role_attr_uncount(hashtab_key_t key __attribute__ ((unused)),
+			     hashtab_datum_t datum, void *args)
+{
+	role_datum_t *role = datum;
+	uint32_t *p_nel = args;
+
+	if (role->flavor == ROLE_ATTRIB) {
+		/* uncount attribute from total number of roles */
+		(*p_nel)--;
+	}
+	return 0;
+}
+
 /*
  * Write the configuration data in a policy database
  * structure to a policy database binary representation
@@ -1926,7 +1970,7 @@ int policydb_write(policydb_t * p, struct policy_file *fp)
 	num_syms = info->sym_num;
 	for (i = 0; i < num_syms; i++) {
 		buf[0] = cpu_to_le32(p->symtab[i].nprim);
-		buf[1] = cpu_to_le32(p->symtab[i].table->nel);
+		buf[1] = p->symtab[i].table->nel;
 
 		/*
 		 * A special case when writing type/attribute symbol table.
@@ -1939,6 +1983,20 @@ int policydb_write(policydb_t * p, struct policy_file *fp)
 		    p->policy_type == POLICY_KERN) {
 			hashtab_map(p->symtab[i].table, type_attr_uncount, &buf[1]);
 		}
+
+		/*
+		 * Another special case when writing role/attribute symbol
+		 * table, role attributes are redundant for policy.X, or
+		 * when the pp's version is not big enough. So deduct
+		 * their numbers from p_roles.table->nel.
+		 */
+		if ((i == SYM_ROLES) &&
+		    ((p->policy_type == POLICY_KERN) ||
+		     (p->policy_type != POLICY_KERN &&
+		      p->policyvers < MOD_POLICYDB_VERSION_ROLEATTRIB)))
+			hashtab_map(p->symtab[i].table, role_attr_uncount, &buf[1]);
+
+		buf[1] = cpu_to_le32(buf[1]);
 		items = put_entry(buf, sizeof(uint32_t), 2, fp);
 		if (items != 2)
 			return POLICYDB_ERROR;