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Accept command-line input for neverallow-check.

Browse source 
Also, divide each sepolicy-analyze function into its own component for simplified
command-line parsing and potentially eventual modularization.
Bug: 18005561

Cherry-pick from: https://android-review.googlesource.com/#/c/111626/

Change-Id: I751a99feffe820308ec58514fdba4cdef184d964
This commit is contained in:
dcashman 2014-10-20 09:52:55 -07:00
parent db4582a996
commit 3fa92beda7
16 changed files with 1217 additions and 1031 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

12
tools/Android.mk
View file

@ -46,14 +46,4 @@ LOCAL_STATIC_LIBRARIES := libsepol
include $(BUILD_HOST_EXECUTABLE) include $(BUILD_HOST_EXECUTABLE)
################################### include $(call all-makefiles-under,$(LOCAL_PATH))
include $(CLEAR_VARS)
LOCAL_MODULE := sepolicy-analyze
LOCAL_MODULE_TAGS := optional
LOCAL_C_INCLUDES := external/libsepol/include
LOCAL_CFLAGS := -Wall -Werror
LOCAL_SRC_FILES := sepolicy-analyze.c
LOCAL_STATIC_LIBRARIES := libsepol
include $(BUILD_HOST_EXECUTABLE)

79
tools/README
View file

@ -50,81 +50,4 @@ sepolicy-check
sepolicy-analyze sepolicy-analyze
A tool for performing various kinds of analysis on a sepolicy A tool for performing various kinds of analysis on a sepolicy
file. The current kinds of analysis that are currently supported file.
include:
TYPE EQUIVALENCE
sepolicy-analyze -e -P out/target/product/<board>/root/sepolicy
Display all type pairs that are "equivalent", i.e. they are
identical with respect to allow rules, including indirect allow
rules via attributes and default-enabled conditional rules
(i.e. default boolean values yield a true conditional expression).
Equivalent types are candidates for being coalesced into a single
type. However, there may be legitimate reasons for them to remain
separate, for example: - the types may differ in a respect not
included in the current analysis, such as default-disabled
conditional rules, audit-related rules (auditallow or dontaudit),
default type transitions, or constraints (e.g. mls), or - the
current policy may be overly permissive with respect to one or the
other of the types and thus the correct action may be to tighten
access to one or the other rather than coalescing them together,
or - the domains that would in fact have different accesses to the
types may not yet be defined or may be unconfined in the policy
you are analyzing.
TYPE DIFFERENCE
sepolicy-analyze -d -P out/target/product/<board>/root/sepolicy
Display type pairs that differ and the first difference found
between the two types. This may be used in looking for similar
types that are not equivalent but may be candidates for coalescing.
DUPLICATE ALLOW RULES
sepolicy-analyze -D -P out/target/product/<board>/root/sepolicy
Displays duplicate allow rules, i.e. pairs of allow rules that
grant the same permissions where one allow rule is written
directly in terms of individual types and the other is written in
terms of attributes associated with those same types. The rule
with individual types is a candidate for removal. The rule with
individual types may be directly represented in the source policy
or may be a result of expansion of a type negation (e.g. domain
-foo -bar is expanded to individual allow rules by the policy
compiler). Domains with unconfineddomain will typically have such
duplicate rules as a natural side effect and can be ignored.
PERMISSIVE DOMAINS
sepolicy-analyze -p -P out/target/product/<board>/root/sepolicy
Displays domains in the policy that are permissive, i.e. avc
denials are logged but not enforced for these domains. While
permissive domains can be helpful during development, they
should not be present in a final -user build.
NEVERALLOW CHECKING
sepolicy-analyze [-w] [-z] -n neverallows.conf -P out/target/product/<board>/root/sepolicy
Check whether the sepolicy file violates any of the neverallow rules
from neverallows.conf. neverallows.conf is a file containing neverallow
statements in the same format as the SELinux policy.conf file, i.e. after
m4 macro expansion of the rules from a .te file. You can use an entire
policy.conf file as the neverallows.conf file and sepolicy-analyze will
ignore everything except for the neverallows within it. If there are
no violations, sepolicy-analyze will exit successfully with no output.
Otherwise, sepolicy-analyze will report all violations and exit
with a non-zero exit status.
The -w or --warn option may be used to warn on any types, attributes,
classes, or permissions from a neverallow rule that could not be resolved
within the sepolicy file. This can be normal due to differences between
the policy from which the neverallow rules were taken and the policy
being checked. Such values are ignored for the purposes of neverallow
checking.
The -z (-d was already taken!) or --debug option may be used to cause
sepolicy-analyze to emit the neverallow rules as it parses them from
the neverallows.conf file. This is principally a debugging facility
for the parser but could also be used to extract neverallow rules from
a full policy.conf file and output them in a more easily parsed format.

942
tools/sepolicy-analyze.c
View file

@ -1,942 +0,0 @@
#include <getopt.h>
#include <unistd.h>
#include <stddef.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
#include <sepol/policydb/policydb.h>
#include <sepol/policydb/services.h>
#include <sepol/policydb/expand.h>
#include <sepol/policydb/util.h>
#include <stdbool.h>
static int debug;
static int warn;
void usage(char *arg0)
{
fprintf(stderr, "%s [-w|--warn] [-z|--debug] [-e|--equiv] [-d|--diff] [-D|--dups] [-p|--permissive] [-n|--neverallow <neverallow file>] -P <policy file>\n", arg0);
exit(1);
}
int load_policy(char *filename, policydb_t * policydb, struct policy_file *pf)
{
int fd;
struct stat sb;
void *map;
int ret;
fd = open(filename, O_RDONLY);
if (fd < 0) {
fprintf(stderr, "Can't open '%s': %s\n", filename, strerror(errno));
return 1;
}
if (fstat(fd, &sb) < 0) {
fprintf(stderr, "Can't stat '%s': %s\n", filename, strerror(errno));
close(fd);
return 1;
}
map = mmap(NULL, sb.st_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
if (map == MAP_FAILED) {
fprintf(stderr, "Can't mmap '%s': %s\n", filename, strerror(errno));
close(fd);
return 1;
}
policy_file_init(pf);
pf->type = PF_USE_MEMORY;
pf->data = map;
pf->len = sb.st_size;
if (policydb_init(policydb)) {
fprintf(stderr, "Could not initialize policydb!\n");
close(fd);
munmap(map, sb.st_size);
return 1;
}
ret = policydb_read(policydb, pf, 0);
if (ret) {
fprintf(stderr, "error(s) encountered while parsing configuration\n");
close(fd);
munmap(map, sb.st_size);
return 1;
}
return 0;
}
static int insert_type_rule(avtab_key_t * k, avtab_datum_t * d,
struct avtab_node *type_rules)
{
struct avtab_node *p, *c, *n;
for (p = type_rules, c = type_rules->next; c; p = c, c = c->next) {
/*
* Find the insertion point, keeping the list
* ordered by source type, then target type, then
* target class.
*/
if (k->source_type < c->key.source_type)
break;
if (k->source_type == c->key.source_type &&
k->target_type < c->key.target_type)
break;
if (k->source_type == c->key.source_type &&
k->target_type == c->key.target_type &&
k->target_class <= c->key.target_class)
break;
}
if (c &&
k->source_type == c->key.source_type &&
k->target_type == c->key.target_type &&
k->target_class == c->key.target_class) {
c->datum.data |= d->data;
return 0;
}
/* Insert the rule */
n = malloc(sizeof(struct avtab_node));
if (!n) {
fprintf(stderr, "out of memory\n");
exit(1);
}
n->key = *k;
n->datum = *d;
n->next = p->next;
p->next = n;
return 0;
}
static int create_type_rules_helper(avtab_key_t * k, avtab_datum_t * d,
void *args)
{
struct avtab_node *type_rules = args;
avtab_key_t key;
/*
* Insert the rule into the list for
* the source type. The source type value
* is cleared as we want to compare against other type
* rules with different source types.
*/
key = *k;
key.source_type = 0;
if (k->source_type == k->target_type) {
/* Clear target type as well; this is a self rule. */
key.target_type = 0;
}
if (insert_type_rule(&key, d, &type_rules[k->source_type - 1]))
return -1;
if (k->source_type == k->target_type)
return 0;
/*
* If the target type differs, then we also
* insert the rule into the list for the target
* type. We clear the target type value so that
* we can compare against other type rules with
* different target types.
*/
key = *k;
key.target_type = 0;
if (insert_type_rule(&key, d, &type_rules[k->target_type - 1]))
return -1;
return 0;
}
static int create_type_rules(avtab_key_t * k, avtab_datum_t * d, void *args)
{
if (k->specified & AVTAB_ALLOWED)
return create_type_rules_helper(k, d, args);
return 0;
}
static int create_type_rules_cond(avtab_key_t * k, avtab_datum_t * d,
void *args)
{
if ((k->specified & (AVTAB_ALLOWED|AVTAB_ENABLED)) ==
(AVTAB_ALLOWED|AVTAB_ENABLED))
return create_type_rules_helper(k, d, args);
return 0;
}
static void free_type_rules(struct avtab_node *l)
{
struct avtab_node *tmp;
while (l) {
tmp = l;
l = l->next;
free(tmp);
}
}
static void display_allow(policydb_t *policydb, avtab_key_t *key, int idx,
uint32_t perms)
{
printf(" allow %s %s:%s { %s };\n",
policydb->p_type_val_to_name[key->source_type
? key->source_type - 1 : idx],
key->target_type == key->source_type ? "self" :
policydb->p_type_val_to_name[key->target_type
? key->target_type - 1 : idx],
policydb->p_class_val_to_name[key->target_class - 1],
sepol_av_to_string
(policydb, key->target_class, perms));
}
static int find_match(policydb_t *policydb, struct avtab_node *l1,
int idx1, struct avtab_node *l2, int idx2)
{
struct avtab_node *c;
uint32_t perms1, perms2;
for (c = l2; c; c = c->next) {
if (l1->key.source_type < c->key.source_type)
break;
if (l1->key.source_type == c->key.source_type &&
l1->key.target_type < c->key.target_type)
break;
if (l1->key.source_type == c->key.source_type &&
l1->key.target_type == c->key.target_type &&
l1->key.target_class <= c->key.target_class)
break;
}
if (c &&
l1->key.source_type == c->key.source_type &&
l1->key.target_type == c->key.target_type &&
l1->key.target_class == c->key.target_class) {
perms1 = l1->datum.data & ~c->datum.data;
perms2 = c->datum.data & ~l1->datum.data;
if (perms1 || perms2) {
if (perms1)
display_allow(policydb, &l1->key, idx1, perms1);
if (perms2)
display_allow(policydb, &c->key, idx2, perms2);
printf("\n");
return 1;
}
}
return 0;
}
static int analyze_types(policydb_t * policydb, char equiv, char diff)
{
avtab_t exp_avtab, exp_cond_avtab;
struct avtab_node *type_rules, *l1, *l2;
struct type_datum *type;
size_t i, j;
/*
* Create a list of access vector rules for each type
* from the access vector table.
*/
type_rules = malloc(sizeof(struct avtab_node) * policydb->p_types.nprim);
if (!type_rules) {
fprintf(stderr, "out of memory\n");
exit(1);
}
memset(type_rules, 0, sizeof(struct avtab_node) * policydb->p_types.nprim);
if (avtab_init(&exp_avtab) || avtab_init(&exp_cond_avtab)) {
fputs("out of memory\n", stderr);
return -1;
}
if (expand_avtab(policydb, &policydb->te_avtab, &exp_avtab)) {
fputs("out of memory\n", stderr);
avtab_destroy(&exp_avtab);
return -1;
}
if (expand_avtab(policydb, &policydb->te_cond_avtab, &exp_cond_avtab)) {
fputs("out of memory\n", stderr);
avtab_destroy(&exp_avtab);
return -1;
}
if (avtab_map(&exp_avtab, create_type_rules, type_rules))
exit(1);
if (avtab_map(&exp_cond_avtab, create_type_rules_cond, type_rules))
exit(1);
avtab_destroy(&exp_avtab);
avtab_destroy(&exp_cond_avtab);
/*
* Compare the type lists and identify similar types.
*/
for (i = 0; i < policydb->p_types.nprim - 1; i++) {
if (!type_rules[i].next)
continue;
type = policydb->type_val_to_struct[i];
if (type->flavor) {
free_type_rules(type_rules[i].next);
type_rules[i].next = NULL;
continue;
}
for (j = i + 1; j < policydb->p_types.nprim; j++) {
type = policydb->type_val_to_struct[j];
if (type->flavor) {
free_type_rules(type_rules[j].next);
type_rules[j].next = NULL;
continue;
}
for (l1 = type_rules[i].next, l2 = type_rules[j].next;
l1 && l2; l1 = l1->next, l2 = l2->next) {
if (l1->key.source_type != l2->key.source_type)
break;
if (l1->key.target_type != l2->key.target_type)
break;
if (l1->key.target_class != l2->key.target_class
|| l1->datum.data != l2->datum.data)
break;
}
if (l1 || l2) {
if (diff) {
printf
("Types %s and %s differ, starting with:\n",
policydb->p_type_val_to_name[i],
policydb->p_type_val_to_name[j]);
if (l1 && l2) {
if (find_match(policydb, l1, i, l2, j))
continue;
if (find_match(policydb, l2, j, l1, i))
continue;
}
if (l1)
display_allow(policydb, &l1->key, i, l1->datum.data);
if (l2)
display_allow(policydb, &l2->key, j, l2->datum.data);
printf("\n");
}
continue;
}
free_type_rules(type_rules[j].next);
type_rules[j].next = NULL;
if (equiv) {
printf("Types %s and %s are equivalent.\n",
policydb->p_type_val_to_name[i],
policydb->p_type_val_to_name[j]);
}
}
free_type_rules(type_rules[i].next);
type_rules[i].next = NULL;
}
free(type_rules);
return 0;
}
static int find_dups_helper(avtab_key_t * k, avtab_datum_t * d,
void *args)
{
policydb_t *policydb = args;
ebitmap_t *sattr, *tattr;
ebitmap_node_t *snode, *tnode;
unsigned int i, j;
avtab_key_t avkey;
avtab_ptr_t node;
struct type_datum *stype, *ttype, *stype2, *ttype2;
bool attrib1, attrib2;
if (!(k->specified & AVTAB_ALLOWED))
return 0;
if (k->source_type == k->target_type)
return 0; /* self rule */
avkey.target_class = k->target_class;
avkey.specified = k->specified;
sattr = &policydb->type_attr_map[k->source_type - 1];
tattr = &policydb->type_attr_map[k->target_type - 1];
stype = policydb->type_val_to_struct[k->source_type - 1];
ttype = policydb->type_val_to_struct[k->target_type - 1];
attrib1 = stype->flavor || ttype->flavor;
ebitmap_for_each_bit(sattr, snode, i) {
if (!ebitmap_node_get_bit(snode, i))
continue;
ebitmap_for_each_bit(tattr, tnode, j) {
if (!ebitmap_node_get_bit(tnode, j))
continue;
avkey.source_type = i + 1;
avkey.target_type = j + 1;
if (avkey.source_type == k->source_type &&
avkey.target_type == k->target_type)
continue;
if (avkey.source_type == avkey.target_type)
continue; /* self rule */
stype2 = policydb->type_val_to_struct[avkey.source_type - 1];
ttype2 = policydb->type_val_to_struct[avkey.target_type - 1];
attrib2 = stype2->flavor || ttype2->flavor;
if (attrib1 && attrib2)
continue; /* overlapping attribute-based rules */
for (node = avtab_search_node(&policydb->te_avtab, &avkey);
node != NULL;
node = avtab_search_node_next(node, avkey.specified)) {
uint32_t perms = node->datum.data & d->data;
if ((attrib1 && perms == node->datum.data) ||
(attrib2 && perms == d->data)) {
/*
* The attribute-based rule is a superset of the
* non-attribute-based rule. This is a dup.
*/
printf("Duplicate allow rule found:\n");
display_allow(policydb, k, i, d->data);
display_allow(policydb, &node->key, i, node->datum.data);
printf("\n");
}
}
}
}
return 0;
}
static int find_dups(policydb_t * policydb)
{
if (avtab_map(&policydb->te_avtab, find_dups_helper, policydb))
return -1;
return 0;
}
static int list_permissive(policydb_t * policydb)
{
struct ebitmap_node *n;
unsigned int bit;
/*
* iterate over all domains and check if domain is in permissive
*/
ebitmap_for_each_bit(&policydb->permissive_map, n, bit)
{
if (ebitmap_node_get_bit(n, bit)) {
printf("%s\n", policydb->p_type_val_to_name[bit -1]);
}
}
return 0;
}
static int read_typeset(policydb_t *policydb, char **ptr, char *end,
type_set_t *typeset, uint32_t *flags)
{
const char *keyword = "self";
size_t keyword_size = strlen(keyword), len;
char *p = *ptr;
unsigned openparens = 0;
char *start, *id;
type_datum_t *type;
struct ebitmap_node *n;
unsigned int bit;
bool negate = false;
int rc;
do {
while (p < end && isspace(*p))
p++;
if (p == end)
goto err;
if (*p == '~') {
if (debug)
printf(" ~");
typeset->flags = TYPE_COMP;
p++;
while (p < end && isspace(*p))
p++;
if (p == end)
goto err;
}
if (*p == '{') {
if (debug && !openparens)
printf(" {");
openparens++;
p++;
continue;
}
if (*p == '}') {
if (debug && openparens == 1)
printf(" }");
if (openparens == 0)
goto err;
openparens--;
p++;
continue;
}
if (*p == '*') {
if (debug)
printf(" *");
typeset->flags = TYPE_STAR;
p++;
continue;
}
if (*p == '-') {
if (debug)
printf(" -");
negate = true;
p++;
continue;
}
if (*p == '#') {
while (p < end && *p != '\n')
p++;
continue;
}
start = p;
while (p < end && !isspace(*p) && *p != ':' && *p != ';' && *p != '{' && *p != '}' && *p != '#')
p++;
if (p == start)
goto err;
len = p - start;
if (len == keyword_size && !strncmp(start, keyword, keyword_size)) {
if (debug)
printf(" self");
*flags |= RULE_SELF;
continue;
}
id = calloc(1, len + 1);
if (!id)
goto err;
memcpy(id, start, len);
if (debug)
printf(" %s", id);
type = hashtab_search(policydb->p_types.table, id);
if (!type) {
if (warn)
fprintf(stderr, "Warning! Type or attribute %s used in neverallow undefined in policy being checked.\n", id);
negate = false;
continue;
}
free(id);
if (type->flavor == TYPE_ATTRIB) {
if (negate)
rc = ebitmap_union(&typeset->negset, &policydb->attr_type_map[type->s.value - 1]);
else
rc = ebitmap_union(&typeset->types, &policydb->attr_type_map[type->s.value - 1]);
} else if (negate) {
rc = ebitmap_set_bit(&typeset->negset, type->s.value - 1, 1);
} else {
rc = ebitmap_set_bit(&typeset->types, type->s.value - 1, 1);
}
negate = false;
if (rc)
goto err;
} while (p < end && openparens);
if (p == end)
goto err;
if (typeset->flags & TYPE_STAR) {
for (bit = 0; bit < policydb->p_types.nprim; bit++) {
if (ebitmap_get_bit(&typeset->negset, bit))
continue;
if (policydb->type_val_to_struct[bit] &&
policydb->type_val_to_struct[bit]->flavor == TYPE_ATTRIB)
continue;
if (ebitmap_set_bit(&typeset->types, bit, 1))
goto err;
}
}
ebitmap_for_each_bit(&typeset->negset, n, bit) {
if (!ebitmap_node_get_bit(n, bit))
continue;
if (ebitmap_set_bit(&typeset->types, bit, 0))
goto err;
}
if (typeset->flags & TYPE_COMP) {
for (bit = 0; bit < policydb->p_types.nprim; bit++) {
if (policydb->type_val_to_struct[bit] &&
policydb->type_val_to_struct[bit]->flavor == TYPE_ATTRIB)
continue;
if (ebitmap_get_bit(&typeset->types, bit))
ebitmap_set_bit(&typeset->types, bit, 0);
else {
if (ebitmap_set_bit(&typeset->types, bit, 1))
goto err;
}
}
}
if (warn && ebitmap_length(&typeset->types) == 0 && !(*flags))
fprintf(stderr, "Warning! Empty type set\n");
*ptr = p;
return 0;
err:
return -1;
}
static int read_classperms(policydb_t *policydb, char **ptr, char *end,
class_perm_node_t **perms)
{
char *p = *ptr;
unsigned openparens = 0;
char *id, *start;
class_datum_t *cls = NULL;
perm_datum_t *perm = NULL;
class_perm_node_t *classperms = NULL, *node = NULL;
bool complement = false;
while (p < end && isspace(*p))
p++;
if (p == end || *p != ':')
goto err;
p++;
if (debug)
printf(" :");
do {
while (p < end && isspace(*p))
p++;
if (p == end)
goto err;
if (*p == '{') {
if (debug && !openparens)
printf(" {");
openparens++;
p++;
continue;
}
if (*p == '}') {
if (debug && openparens == 1)
printf(" }");
if (openparens == 0)
goto err;
openparens--;
p++;
continue;
}
if (*p == '#') {
while (p < end && *p != '\n')
p++;
continue;
}
start = p;
while (p < end && !isspace(*p) && *p != '{' && *p != '}' && *p != ';' && *p != '#')
p++;
if (p == start)
goto err;
id = calloc(1, p - start + 1);
if (!id)
goto err;
memcpy(id, start, p - start);
if (debug)
printf(" %s", id);
cls = hashtab_search(policydb->p_classes.table, id);
if (!cls) {
if (warn)
fprintf(stderr, "Warning! Class %s used in neverallow undefined in policy being checked.\n", id);
continue;
}
node = calloc(1, sizeof *node);
if (!node)
goto err;
node->class = cls->s.value;
node->next = classperms;
classperms = node;
free(id);
} while (p < end && openparens);
if (p == end)
goto err;
if (warn && !classperms)
fprintf(stderr, "Warning! Empty class set\n");
do {
while (p < end && isspace(*p))
p++;
if (p == end)
goto err;
if (*p == '~') {
if (debug)
printf(" ~");
complement = true;
p++;
while (p < end && isspace(*p))
p++;
if (p == end)
goto err;
}
if (*p == '{') {
if (debug && !openparens)
printf(" {");
openparens++;
p++;
continue;
}
if (*p == '}') {
if (debug && openparens == 1)
printf(" }");
if (openparens == 0)
goto err;
openparens--;
p++;
continue;
}
if (*p == '#') {
while (p < end && *p != '\n')
p++;
continue;
}
start = p;
while (p < end && !isspace(*p) && *p != '{' && *p != '}' && *p != ';' && *p != '#')
p++;
if (p == start)
goto err;
id = calloc(1, p - start + 1);
if (!id)
goto err;
memcpy(id, start, p - start);
if (debug)
printf(" %s", id);
if (!strcmp(id, "*")) {
for (node = classperms; node; node = node->next)
node->data = ~0;
continue;
}
for (node = classperms; node; node = node->next) {
cls = policydb->class_val_to_struct[node->class-1];
perm = hashtab_search(cls->permissions.table, id);
if (cls->comdatum && !perm)
perm = hashtab_search(cls->comdatum->permissions.table, id);
if (!perm) {
if (warn)
fprintf(stderr, "Warning! Permission %s used in neverallow undefined in class %s in policy being checked.\n", id, policydb->p_class_val_to_name[node->class-1]);
continue;
}
node->data |= 1U << (perm->s.value - 1);
}
free(id);
} while (p < end && openparens);
if (p == end)
goto err;
if (complement) {
for (node = classperms; node; node = node->next)
node->data = ~node->data;
}
if (warn) {
for (node = classperms; node; node = node->next)
if (!node->data)
fprintf(stderr, "Warning! Empty permission set\n");
}
*perms = classperms;
*ptr = p;
return 0;
err:
return -1;
}
static int check_neverallows(policydb_t *policydb, const char *filename)
{
const char *keyword = "neverallow";
size_t keyword_size = strlen(keyword), len;
struct avrule *neverallows = NULL, *avrule;
int fd;
struct stat sb;
char *text, *end, *start;
char *p;
fd = open(filename, O_RDONLY);
if (fd < 0) {
fprintf(stderr, "Could not open %s: %s\n", filename, strerror(errno));
return -1;
}
if (fstat(fd, &sb) < 0) {
fprintf(stderr, "Can't stat '%s': %s\n", filename, strerror(errno));
close(fd);
return -1;
}
text = mmap(NULL, sb.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
end = text + sb.st_size;
if (text == MAP_FAILED) {
fprintf(stderr, "Can't mmap '%s': %s\n", filename, strerror(errno));
close(fd);
return -1;
}
close(fd);
p = text;
while (p < end) {
while (p < end && isspace(*p))
p++;
if (*p == '#') {
while (p < end && *p != '\n')
p++;
continue;
}
start = p;
while (p < end && !isspace(*p))
p++;
len = p - start;
if (len != keyword_size || strncmp(start, keyword, keyword_size))
continue;
if (debug)
printf("neverallow");
avrule = calloc(1, sizeof *avrule);
if (!avrule)
goto err;
avrule->specified = AVRULE_NEVERALLOW;
if (read_typeset(policydb, &p, end, &avrule->stypes, &avrule->flags))
goto err;
if (read_typeset(policydb, &p, end, &avrule->ttypes, &avrule->flags))
goto err;
if (read_classperms(policydb, &p, end, &avrule->perms))
goto err;
while (p < end && *p != ';')
p++;
if (p == end || *p != ';')
goto err;
if (debug)
printf(";\n");
avrule->next = neverallows;
neverallows = avrule;
}
return check_assertions(NULL, policydb, neverallows);
err:
if (errno == ENOMEM) {
fprintf(stderr, "Out of memory while parsing %s\n", filename);
} else
fprintf(stderr, "Error while parsing %s\n", filename);
return -1;
}
int main(int argc, char **argv)
{
char *policy = NULL, *neverallows = NULL;
struct policy_file pf;
policydb_t policydb;
char ch;
char equiv = 0, diff = 0, dups = 0, permissive = 0;
int rc = 0;
struct option long_options[] = {
{"equiv", no_argument, NULL, 'e'},
{"debug", no_argument, NULL, 'z'},
{"diff", no_argument, NULL, 'd'},
{"dups", no_argument, NULL, 'D'},
{"neverallow", required_argument, NULL, 'n'},
{"permissive", no_argument, NULL, 'p'},
{"policy", required_argument, NULL, 'P'},
{"warn", no_argument, NULL, 'w'},
{NULL, 0, NULL, 0}
};
while ((ch = getopt_long(argc, argv, "edDpn:P:wz", long_options, NULL)) != -1) {
switch (ch) {
case 'e':
equiv = 1;
break;
case 'd':
diff = 1;
break;
case 'D':
dups = 1;
break;
case 'n':
neverallows = optarg;
break;
case 'p':
permissive = 1;
break;
case 'P':
policy = optarg;
break;
case 'w':
warn = 1;
break;
case 'z':
debug = 1;
break;
default:
usage(argv[0]);
}
}
if (!policy || (!equiv && !diff && !dups && !permissive && !neverallows))
usage(argv[0]);
if (load_policy(policy, &policydb, &pf))
exit(1);
if (equiv || diff)
analyze_types(&policydb, equiv, diff);
if (dups)
find_dups(&policydb);
if (permissive)
list_permissive(&policydb);
if (neverallows)
rc |= check_neverallows(&policydb, neverallows);
policydb_destroy(&policydb);
return rc;
}

13
tools/sepolicy-analyze/Android.mk Normal file
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@ -0,0 +1,13 @@
LOCAL_PATH:= $(call my-dir)
###################################
include $(CLEAR_VARS)
LOCAL_MODULE := sepolicy-analyze
LOCAL_MODULE_TAGS := optional
LOCAL_C_INCLUDES := external/libsepol/include
LOCAL_CFLAGS := -Wall -Werror
LOCAL_SRC_FILES := sepolicy-analyze.c dups.c neverallow.c perm.c typecmp.c utils.c
LOCAL_STATIC_LIBRARIES := libsepol
include $(BUILD_HOST_EXECUTABLE)

82
tools/sepolicy-analyze/README Normal file
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@ -0,0 +1,82 @@
sepolicy-analyze
A component-ized tool for performing various kinds of analysis on a
sepolicy file. The current kinds of analysis that are currently
supported include:
TYPE EQUIVALENCE (typecmp)
sepolicy-analyze out/target/product/<board>/root/sepolicy typecmp -e
Display all type pairs that are "equivalent", i.e. they are
identical with respect to allow rules, including indirect allow
rules via attributes and default-enabled conditional rules
(i.e. default boolean values yield a true conditional expression).
Equivalent types are candidates for being coalesced into a single
type. However, there may be legitimate reasons for them to remain
separate, for example: - the types may differ in a respect not
included in the current analysis, such as default-disabled
conditional rules, audit-related rules (auditallow or dontaudit),
default type transitions, or constraints (e.g. mls), or - the
current policy may be overly permissive with respect to one or the
other of the types and thus the correct action may be to tighten
access to one or the other rather than coalescing them together,
or - the domains that would in fact have different accesses to the
types may not yet be defined or may be unconfined in the policy
you are analyzing.
TYPE DIFFERENCE (typecmp)
sepolicy-analyze out/target/product/<board>/root/sepolicy typecmp -d
Display type pairs that differ and the first difference found
between the two types. This may be used in looking for similar
types that are not equivalent but may be candidates for coalescing.
DUPLICATE ALLOW RULES (dups)
sepolicy-analyze out/target/product/<board>/root/sepolicy dups
Displays duplicate allow rules, i.e. pairs of allow rules that
grant the same permissions where one allow rule is written
directly in terms of individual types and the other is written in
terms of attributes associated with those same types. The rule
with individual types is a candidate for removal. The rule with
individual types may be directly represented in the source policy
or may be a result of expansion of a type negation (e.g. domain
-foo -bar is expanded to individual allow rules by the policy
compiler). Domains with unconfineddomain will typically have such
duplicate rules as a natural side effect and can be ignored.
PERMISSIVE DOMAINS (permissive)
sepolicy-analyze out/target/product/<board>/root/sepolicy permissive
Displays domains in the policy that are permissive, i.e. avc
denials are logged but not enforced for these domains. While
permissive domains can be helpful during development, they
should not be present in a final -user build.
NEVERALLOW CHECKING (neverallow)
sepolicy-analyze out/target/product/<board>/root/sepolicy neverallow \
[-w] [-d] [-f neverallows.conf] | [-n "neverallow string"]
Check whether the sepolicy file violates any of the neverallow rules
from the neverallows.conf file or a given string, which contain neverallow
statements in the same format as the SELinux policy.conf file, i.e. after
m4 macro expansion of the rules from a .te file. You can use an entire
policy.conf file as the neverallows.conf file and sepolicy-analyze will
ignore everything except for the neverallows within it. You can also
specify this as a command-line string argument, which could be useful for
quickly checking an individual expanded rule or group of rules. If there are
no violations, sepolicy-analyze will exit successfully with no output.
Otherwise, sepolicy-analyze will report all violations and exit
with a non-zero exit status.
The -w or --warn option may be used to warn on any types, attributes,
classes, or permissions from a neverallow rule that could not be resolved
within the sepolicy file. This can be normal due to differences between
the policy from which the neverallow rules were taken and the policy
being checked. Such values are ignored for the purposes of neverallow
checking.
The -d or --debug option may be used to cause sepolicy-analyze to emit the
neverallow rules as it parses them. This is principally a debugging facility
for the parser but could also be used to extract neverallow rules from
a full policy.conf file and output them in a more easily parsed format.

91
tools/sepolicy-analyze/dups.c Normal file
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@ -0,0 +1,91 @@
#include <stdbool.h>
#include <stdio.h>
#include <sys/stat.h>
#include <sys/types.h>
#include "dups.h"
void dups_usage() {
fprintf(stderr, "\tdups\n");
}
static int find_dups_helper(avtab_key_t * k, avtab_datum_t * d,
void *args)
{
policydb_t *policydb = args;
ebitmap_t *sattr, *tattr;
ebitmap_node_t *snode, *tnode;
unsigned int i, j;
avtab_key_t avkey;
avtab_ptr_t node;
struct type_datum *stype, *ttype, *stype2, *ttype2;
bool attrib1, attrib2;
if (!(k->specified & AVTAB_ALLOWED))
return 0;
if (k->source_type == k->target_type)
return 0; /* self rule */
avkey.target_class = k->target_class;
avkey.specified = k->specified;
sattr = &policydb->type_attr_map[k->source_type - 1];
tattr = &policydb->type_attr_map[k->target_type - 1];
stype = policydb->type_val_to_struct[k->source_type - 1];
ttype = policydb->type_val_to_struct[k->target_type - 1];
attrib1 = stype->flavor || ttype->flavor;
ebitmap_for_each_bit(sattr, snode, i) {
if (!ebitmap_node_get_bit(snode, i))
continue;
ebitmap_for_each_bit(tattr, tnode, j) {
if (!ebitmap_node_get_bit(tnode, j))
continue;
avkey.source_type = i + 1;
avkey.target_type = j + 1;
if (avkey.source_type == k->source_type &&
avkey.target_type == k->target_type)
continue;
if (avkey.source_type == avkey.target_type)
continue; /* self rule */
stype2 = policydb->type_val_to_struct[avkey.source_type - 1];
ttype2 = policydb->type_val_to_struct[avkey.target_type - 1];
attrib2 = stype2->flavor || ttype2->flavor;
if (attrib1 && attrib2)
continue; /* overlapping attribute-based rules */
for (node = avtab_search_node(&policydb->te_avtab, &avkey);
node != NULL;
node = avtab_search_node_next(node, avkey.specified)) {
uint32_t perms = node->datum.data & d->data;
if ((attrib1 && perms == node->datum.data) ||
(attrib2 && perms == d->data)) {
/*
* The attribute-based rule is a superset of the
* non-attribute-based rule. This is a dup.
*/
printf("Duplicate allow rule found:\n");
display_allow(policydb, k, i, d->data);
display_allow(policydb, &node->key, i, node->datum.data);
printf("\n");
}
}
}
}
return 0;
}
static int find_dups(policydb_t * policydb)
{
if (avtab_map(&policydb->te_avtab, find_dups_helper, policydb))
return -1;
return 0;
}
int dups_func (int argc, __attribute__ ((unused)) char **argv, policydb_t *policydb) {
if (argc != 1) {
USAGE_ERROR = true;
return -1;
}
return find_dups(policydb);
}

11
tools/sepolicy-analyze/dups.h Normal file
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@ -0,0 +1,11 @@
#ifndef DUPS_H
#define DUPS_H
#include <sepol/policydb/policydb.h>
#include "utils.h"
void dups_usage(void);
int dups_func(int argc, char **argv, policydb_t *policydb);
#endif /* DUPS_H */

515
tools/sepolicy-analyze/neverallow.c Normal file
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@ -0,0 +1,515 @@
#include <ctype.h>
#include <fcntl.h>
#include <getopt.h>
#include <stdbool.h>
#include <stdio.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include "neverallow.h"
static int debug;
static int warn;
void neverallow_usage() {
fprintf(stderr, "\tneverallow [-w|--warn] [-d|--debug] [-n|--neverallows <neverallow-rules>] | [-f|--file <neverallow-file>]\n");
}
static int read_typeset(policydb_t *policydb, char **ptr, char *end,
type_set_t *typeset, uint32_t *flags)
{
const char *keyword = "self";
size_t keyword_size = strlen(keyword), len;
char *p = *ptr;
unsigned openparens = 0;
char *start, *id;
type_datum_t *type;
struct ebitmap_node *n;
unsigned int bit;
bool negate = false;
int rc;
do {
while (p < end && isspace(*p))
p++;
if (p == end)
goto err;
if (*p == '~') {
if (debug)
printf(" ~");
typeset->flags = TYPE_COMP;
p++;
while (p < end && isspace(*p))
p++;
if (p == end)
goto err;
}
if (*p == '{') {
if (debug && !openparens)
printf(" {");
openparens++;
p++;
continue;
}
if (*p == '}') {
if (debug && openparens == 1)
printf(" }");
if (openparens == 0)
goto err;
openparens--;
p++;
continue;
}
if (*p == '*') {
if (debug)
printf(" *");
typeset->flags = TYPE_STAR;
p++;
continue;
}
if (*p == '-') {
if (debug)
printf(" -");
negate = true;
p++;
continue;
}
if (*p == '#') {
while (p < end && *p != '\n')
p++;
continue;
}
start = p;
while (p < end && !isspace(*p) && *p != ':' && *p != ';' && *p != '{' && *p != '}' && *p != '#')
p++;
if (p == start)
goto err;
len = p - start;
if (len == keyword_size && !strncmp(start, keyword, keyword_size)) {
if (debug)
printf(" self");
*flags |= RULE_SELF;
continue;
}
id = calloc(1, len + 1);
if (!id)
goto err;
memcpy(id, start, len);
if (debug)
printf(" %s", id);
type = hashtab_search(policydb->p_types.table, id);
if (!type) {
if (warn)
fprintf(stderr, "Warning! Type or attribute %s used in neverallow undefined in policy being checked.\n", id);
negate = false;
continue;
}
free(id);
if (type->flavor == TYPE_ATTRIB) {
if (negate)
rc = ebitmap_union(&typeset->negset, &policydb->attr_type_map[type->s.value - 1]);
else
rc = ebitmap_union(&typeset->types, &policydb->attr_type_map[type->s.value - 1]);
} else if (negate) {
rc = ebitmap_set_bit(&typeset->negset, type->s.value - 1, 1);
} else {
rc = ebitmap_set_bit(&typeset->types, type->s.value - 1, 1);
}
negate = false;
if (rc)
goto err;
} while (p < end && openparens);
if (p == end)
goto err;
if (typeset->flags & TYPE_STAR) {
for (bit = 0; bit < policydb->p_types.nprim; bit++) {
if (ebitmap_get_bit(&typeset->negset, bit))
continue;
if (policydb->type_val_to_struct[bit] &&
policydb->type_val_to_struct[bit]->flavor == TYPE_ATTRIB)
continue;
if (ebitmap_set_bit(&typeset->types, bit, 1))
goto err;
}
}
ebitmap_for_each_bit(&typeset->negset, n, bit) {
if (!ebitmap_node_get_bit(n, bit))
continue;
if (ebitmap_set_bit(&typeset->types, bit, 0))
goto err;
}
if (typeset->flags & TYPE_COMP) {
for (bit = 0; bit < policydb->p_types.nprim; bit++) {
if (policydb->type_val_to_struct[bit] &&
policydb->type_val_to_struct[bit]->flavor == TYPE_ATTRIB)
continue;
if (ebitmap_get_bit(&typeset->types, bit))
ebitmap_set_bit(&typeset->types, bit, 0);
else {
if (ebitmap_set_bit(&typeset->types, bit, 1))
goto err;
}
}
}
if (warn && ebitmap_length(&typeset->types) == 0 && !(*flags))
fprintf(stderr, "Warning! Empty type set\n");
*ptr = p;
return 0;
err:
return -1;
}
static int read_classperms(policydb_t *policydb, char **ptr, char *end,
class_perm_node_t **perms)
{
char *p = *ptr;
unsigned openparens = 0;
char *id, *start;
class_datum_t *cls = NULL;
perm_datum_t *perm = NULL;
class_perm_node_t *classperms = NULL, *node = NULL;
bool complement = false;
while (p < end && isspace(*p))
p++;
if (p == end || *p != ':')
goto err;
p++;
if (debug)
printf(" :");
do {
while (p < end && isspace(*p))
p++;
if (p == end)
goto err;
if (*p == '{') {
if (debug && !openparens)
printf(" {");
openparens++;
p++;
continue;
}
if (*p == '}') {
if (debug && openparens == 1)
printf(" }");
if (openparens == 0)
goto err;
openparens--;
p++;
continue;
}
if (*p == '#') {
while (p < end && *p != '\n')
p++;
continue;
}
start = p;
while (p < end && !isspace(*p) && *p != '{' && *p != '}' && *p != ';' && *p != '#')
p++;
if (p == start)
goto err;
id = calloc(1, p - start + 1);
if (!id)
goto err;
memcpy(id, start, p - start);
if (debug)
printf(" %s", id);
cls = hashtab_search(policydb->p_classes.table, id);
if (!cls) {
if (warn)
fprintf(stderr, "Warning! Class %s used in neverallow undefined in policy being checked.\n", id);
continue;
}
node = calloc(1, sizeof *node);
if (!node)
goto err;
node->class = cls->s.value;
node->next = classperms;
classperms = node;
free(id);
} while (p < end && openparens);
if (p == end)
goto err;
if (warn && !classperms)
fprintf(stderr, "Warning! Empty class set\n");
do {
while (p < end && isspace(*p))
p++;
if (p == end)
goto err;
if (*p == '~') {
if (debug)
printf(" ~");
complement = true;
p++;
while (p < end && isspace(*p))
p++;
if (p == end)
goto err;
}
if (*p == '{') {
if (debug && !openparens)
printf(" {");
openparens++;
p++;
continue;
}
if (*p == '}') {
if (debug && openparens == 1)
printf(" }");
if (openparens == 0)
goto err;
openparens--;
p++;
continue;
}
if (*p == '#') {
while (p < end && *p != '\n')
p++;
continue;
}
start = p;
while (p < end && !isspace(*p) && *p != '{' && *p != '}' && *p != ';' && *p != '#')
p++;
if (p == start)
goto err;
id = calloc(1, p - start + 1);
if (!id)
goto err;
memcpy(id, start, p - start);
if (debug)
printf(" %s", id);
if (!strcmp(id, "*")) {
for (node = classperms; node; node = node->next)
node->data = ~0;
continue;
}
for (node = classperms; node; node = node->next) {
cls = policydb->class_val_to_struct[node->class-1];
perm = hashtab_search(cls->permissions.table, id);
if (cls->comdatum && !perm)
perm = hashtab_search(cls->comdatum->permissions.table, id);
if (!perm) {
if (warn)
fprintf(stderr, "Warning! Permission %s used in neverallow undefined in class %s in policy being checked.\n", id, policydb->p_class_val_to_name[node->class-1]);
continue;
}
node->data |= 1U << (perm->s.value - 1);
}
free(id);
} while (p < end && openparens);
if (p == end)
goto err;
if (complement) {
for (node = classperms; node; node = node->next)
node->data = ~node->data;
}
if (warn) {
for (node = classperms; node; node = node->next)
if (!node->data)
fprintf(stderr, "Warning! Empty permission set\n");
}
*perms = classperms;
*ptr = p;
return 0;
err:
return -1;
}
static int check_neverallows(policydb_t *policydb, char *text, char *end)
{
const char *keyword = "neverallow";
size_t keyword_size = strlen(keyword), len;
struct avrule *neverallows = NULL, *avrule;
char *p, *start;
p = text;
while (p < end) {
while (p < end && isspace(*p))
p++;
if (*p == '#') {
while (p < end && *p != '\n')
p++;
continue;
}
start = p;
while (p < end && !isspace(*p))
p++;
len = p - start;
if (len != keyword_size || strncmp(start, keyword, keyword_size))
continue;
if (debug)
printf("neverallow");
avrule = calloc(1, sizeof *avrule);
if (!avrule)
goto err;
avrule->specified = AVRULE_NEVERALLOW;
if (read_typeset(policydb, &p, end, &avrule->stypes, &avrule->flags))
goto err;
if (read_typeset(policydb, &p, end, &avrule->ttypes, &avrule->flags))
goto err;
if (read_classperms(policydb, &p, end, &avrule->perms))
goto err;
while (p < end && *p != ';')
p++;
if (p == end || *p != ';')
goto err;
if (debug)
printf(";\n");
avrule->next = neverallows;
neverallows = avrule;
}
if (!neverallows)
goto err;
return check_assertions(NULL, policydb, neverallows);
err:
if (errno == ENOMEM) {
fprintf(stderr, "Out of memory while parsing neverallow rules\n");
} else
fprintf(stderr, "Error while parsing neverallow rules\n");
return -1;
}
static int check_neverallows_file(policydb_t *policydb, const char *filename)
{
int fd;
struct stat sb;
char *text, *end;
fd = open(filename, O_RDONLY);
if (fd < 0) {
fprintf(stderr, "Could not open %s: %s\n", filename, strerror(errno));
return -1;
}
if (fstat(fd, &sb) < 0) {
fprintf(stderr, "Can't stat '%s': %s\n", filename, strerror(errno));
close(fd);
return -1;
}
text = mmap(NULL, sb.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
end = text + sb.st_size;
if (text == MAP_FAILED) {
fprintf(stderr, "Can't mmap '%s': %s\n", filename, strerror(errno));
close(fd);
return -1;
}
close(fd);
return check_neverallows(policydb, text, end);
}
static int check_neverallows_string(policydb_t *policydb, char *string, size_t len)
{
char *text, *end;
text = string;
end = text + len;
return check_neverallows(policydb, text, end);
}
int neverallow_func (int argc, char **argv, policydb_t *policydb) {
char *rules = 0, *file = 0;
char ch;
struct option neverallow_options[] = {
{"debug", no_argument, NULL, 'd'},
{"file_input", required_argument, NULL, 'f'},
{"neverallow", required_argument, NULL, 'n'},
{"warn", no_argument, NULL, 'w'},
{NULL, 0, NULL, 0}
};
while ((ch = getopt_long(argc, argv, "df:n:w", neverallow_options, NULL)) != -1) {
switch (ch) {
case 'd':
debug = 1;
break;
case 'f':
file = optarg;
break;
case 'n':
rules = optarg;
break;
case 'w':
warn = 1;
break;
default:
USAGE_ERROR = true;
return -1;
}
}
if (!(rules || file) || (rules && file)){
USAGE_ERROR = true;
return -1;
}
if (file) {
return check_neverallows_file(policydb, file);
} else {
return check_neverallows_string(policydb, rules, strlen(rules));
}
}

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#ifndef NEVERALLOW_H
#define NEVERALLOW_H
#include <sepol/policydb/policydb.h>
#include "utils.h"
void neverallow_usage(void);
int neverallow_func(int argc, char **argv, policydb_t *policydb);
#endif /* NEVERALLOW_H */

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#include "perm.h"
void permissive_usage() {
fprintf(stderr, "\tpermissive\n");
}
static int list_permissive(policydb_t * policydb)
{
struct ebitmap_node *n;
unsigned int bit;
/*
* iterate over all domains and check if domain is in permissive
*/
ebitmap_for_each_bit(&policydb->permissive_map, n, bit)
{
if (ebitmap_node_get_bit(n, bit)) {
printf("%s\n", policydb->p_type_val_to_name[bit -1]);
}
}
return 0;
}
int permissive_func (int argc, __attribute__ ((unused)) char **argv, policydb_t *policydb) {
if (argc != 1) {
USAGE_ERROR = true;
return -1;
}
return list_permissive(policydb);
}

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#ifndef PERM_H
#define PERM_H
#include <sepol/policydb/policydb.h>
#include "utils.h"
void permissive_usage(void);
int permissive_func(int argc, char **argv, policydb_t *policydb);
#endif /* PERM_H */

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#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include "dups.h"
#include "neverallow.h"
#include "perm.h"
#include "typecmp.h"
#include "utils.h"
#define NUM_COMPONENTS (int) (sizeof(analyze_components)/sizeof(analyze_components[0]))
#define COMP(x) { #x, sizeof(#x) - 1, x ##_usage, x ##_func }
static struct {
const char *key;
size_t keylen;
void (*usage) (void);
int (*func) (int argc, char **argv, policydb_t *policydb);
} analyze_components[] = {
COMP(dups),
COMP(neverallow),
COMP(permissive),
COMP(typecmp)
};
void usage(char *arg0)
{
int i;
fprintf(stderr, "%s must be called on a policy file with a component and the appropriate arguments specified\n", arg0);
fprintf(stderr, "%s <policy-file>:\n", arg0);
for(i = 0; i < NUM_COMPONENTS; i++) {
analyze_components[i].usage();
}
exit(1);
}
int main(int argc, char **argv)
{
char *policy;
struct policy_file pf;
policydb_t policydb;
int rc, i;
if (argc < 3)
usage(argv[0]);
policy = argv[1];
if(load_policy(policy, &policydb, &pf))
exit(1);
for(i = 0; i < NUM_COMPONENTS; i++) {
if (!strcmp(analyze_components[i].key, argv[2])) {
rc = analyze_components[i].func(argc - 2, argv + 2, &policydb);
if (rc && USAGE_ERROR) {
usage(argv[0]); }
return rc;
}
}
usage(argv[0]);
// will never be called due to exit() call in usage
exit(1);
}

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#include <getopt.h>
#include <sepol/policydb/expand.h>
#include "typecmp.h"
void typecmp_usage() {
fprintf(stderr, "\ttypecmp [-d|--diff] [-e|--equiv]\n");
}
static int insert_type_rule(avtab_key_t * k, avtab_datum_t * d,
struct avtab_node *type_rules)
{
struct avtab_node *p, *c, *n;
for (p = type_rules, c = type_rules->next; c; p = c, c = c->next) {
/*
* Find the insertion point, keeping the list
* ordered by source type, then target type, then
* target class.
*/
if (k->source_type < c->key.source_type)
break;
if (k->source_type == c->key.source_type &&
k->target_type < c->key.target_type)
break;
if (k->source_type == c->key.source_type &&
k->target_type == c->key.target_type &&
k->target_class <= c->key.target_class)
break;
}
if (c &&
k->source_type == c->key.source_type &&
k->target_type == c->key.target_type &&
k->target_class == c->key.target_class) {
c->datum.data |= d->data;
return 0;
}
/* Insert the rule */
n = malloc(sizeof(struct avtab_node));
if (!n) {
fprintf(stderr, "out of memory\n");
exit(1);
}
n->key = *k;
n->datum = *d;
n->next = p->next;
p->next = n;
return 0;
}
static int create_type_rules_helper(avtab_key_t * k, avtab_datum_t * d,
void *args)
{
struct avtab_node *type_rules = args;
avtab_key_t key;
/*
* Insert the rule into the list for
* the source type. The source type value
* is cleared as we want to compare against other type
* rules with different source types.
*/
key = *k;
key.source_type = 0;
if (k->source_type == k->target_type) {
/* Clear target type as well; this is a self rule. */
key.target_type = 0;
}
if (insert_type_rule(&key, d, &type_rules[k->source_type - 1]))
return -1;
if (k->source_type == k->target_type)
return 0;
/*
* If the target type differs, then we also
* insert the rule into the list for the target
* type. We clear the target type value so that
* we can compare against other type rules with
* different target types.
*/
key = *k;
key.target_type = 0;
if (insert_type_rule(&key, d, &type_rules[k->target_type - 1]))
return -1;
return 0;
}
static int create_type_rules(avtab_key_t * k, avtab_datum_t * d, void *args)
{
if (k->specified & AVTAB_ALLOWED)
return create_type_rules_helper(k, d, args);
return 0;
}
static int create_type_rules_cond(avtab_key_t * k, avtab_datum_t * d,
void *args)
{
if ((k->specified & (AVTAB_ALLOWED|AVTAB_ENABLED)) ==
(AVTAB_ALLOWED|AVTAB_ENABLED))
return create_type_rules_helper(k, d, args);
return 0;
}
static void free_type_rules(struct avtab_node *l)
{
struct avtab_node *tmp;
while (l) {
tmp = l;
l = l->next;
free(tmp);
}
}
static int find_match(policydb_t *policydb, struct avtab_node *l1,
int idx1, struct avtab_node *l2, int idx2)
{
struct avtab_node *c;
uint32_t perms1, perms2;
for (c = l2; c; c = c->next) {
if (l1->key.source_type < c->key.source_type)
break;
if (l1->key.source_type == c->key.source_type &&
l1->key.target_type < c->key.target_type)
break;
if (l1->key.source_type == c->key.source_type &&
l1->key.target_type == c->key.target_type &&
l1->key.target_class <= c->key.target_class)
break;
}
if (c &&
l1->key.source_type == c->key.source_type &&
l1->key.target_type == c->key.target_type &&
l1->key.target_class == c->key.target_class) {
perms1 = l1->datum.data & ~c->datum.data;
perms2 = c->datum.data & ~l1->datum.data;
if (perms1 || perms2) {
if (perms1)
display_allow(policydb, &l1->key, idx1, perms1);
if (perms2)
display_allow(policydb, &c->key, idx2, perms2);
printf("\n");
return 1;
}
}
return 0;
}
static int analyze_types(policydb_t * policydb, char diff, char equiv)
{
avtab_t exp_avtab, exp_cond_avtab;
struct avtab_node *type_rules, *l1, *l2;
struct type_datum *type;
size_t i, j;
/*
* Create a list of access vector rules for each type
* from the access vector table.
*/
type_rules = malloc(sizeof(struct avtab_node) * policydb->p_types.nprim);
if (!type_rules) {
fprintf(stderr, "out of memory\n");
exit(1);
}
memset(type_rules, 0, sizeof(struct avtab_node) * policydb->p_types.nprim);
if (avtab_init(&exp_avtab) || avtab_init(&exp_cond_avtab)) {
fputs("out of memory\n", stderr);
return -1;
}
if (expand_avtab(policydb, &policydb->te_avtab, &exp_avtab)) {
fputs("out of memory\n", stderr);
avtab_destroy(&exp_avtab);
return -1;
}
if (expand_avtab(policydb, &policydb->te_cond_avtab, &exp_cond_avtab)) {
fputs("out of memory\n", stderr);
avtab_destroy(&exp_avtab); /* */
return -1;
}
if (avtab_map(&exp_avtab, create_type_rules, type_rules))
exit(1);
if (avtab_map(&exp_cond_avtab, create_type_rules_cond, type_rules))
exit(1);
avtab_destroy(&exp_avtab);
avtab_destroy(&exp_cond_avtab);
/*
* Compare the type lists and identify similar types.
*/
for (i = 0; i < policydb->p_types.nprim - 1; i++) {
if (!type_rules[i].next)
continue;
type = policydb->type_val_to_struct[i];
if (type->flavor) {
free_type_rules(type_rules[i].next);
type_rules[i].next = NULL;
continue;
}
for (j = i + 1; j < policydb->p_types.nprim; j++) {
type = policydb->type_val_to_struct[j];
if (type->flavor) {
free_type_rules(type_rules[j].next);
type_rules[j].next = NULL;
continue;
}
for (l1 = type_rules[i].next, l2 = type_rules[j].next;
l1 && l2; l1 = l1->next, l2 = l2->next) {
if (l1->key.source_type != l2->key.source_type)
break;
if (l1->key.target_type != l2->key.target_type)
break;
if (l1->key.target_class != l2->key.target_class
|| l1->datum.data != l2->datum.data)
break;
}
if (l1 || l2) {
if (diff) {
printf
("Types %s and %s differ, starting with:\n",
policydb->p_type_val_to_name[i],
policydb->p_type_val_to_name[j]);
if (l1 && l2) {
if (find_match(policydb, l1, i, l2, j))
continue;
if (find_match(policydb, l2, j, l1, i))
continue;
}
if (l1)
display_allow(policydb, &l1->key, i, l1->datum.data);
if (l2)
display_allow(policydb, &l2->key, j, l2->datum.data);
printf("\n");
}
continue;
}
free_type_rules(type_rules[j].next);
type_rules[j].next = NULL;
if (equiv) {
printf("Types %s and %s are equivalent.\n",
policydb->p_type_val_to_name[i],
policydb->p_type_val_to_name[j]);
}
}
free_type_rules(type_rules[i].next);
type_rules[i].next = NULL;
}
free(type_rules);
return 0;
}
int typecmp_func (int argc, char **argv, policydb_t *policydb) {
char ch, diff = 0, equiv = 0;
struct option typecmp_options[] = {
{"diff", no_argument, NULL, 'd'},
{"equiv", no_argument, NULL, 'e'},
{NULL, 0, NULL, 0}
};
while ((ch = getopt_long(argc, argv, "de", typecmp_options, NULL)) != -1) {
switch (ch) {
case 'd':
diff = 1;
break;
case 'e':
equiv = 1;
break;
default:
USAGE_ERROR = true;
return -1;
}
}
if (!(diff || equiv)) {
USAGE_ERROR = true;
return -1;
}
return analyze_types(policydb, diff, equiv);
}

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#ifndef TYPECMP_H
#define TYPECMP_H
#include <sepol/policydb/policydb.h>
#include "utils.h"
void typecmp_usage(void);
int typecmp_func(int argc, char **argv, policydb_t *policydb);
#endif /* TYPECMP_H */

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#include <fcntl.h>
#include <sepol/policydb/policydb.h>
#include <sepol/policydb/util.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <unistd.h>
#include "utils.h"
bool USAGE_ERROR = false;
void display_allow(policydb_t *policydb, avtab_key_t *key, int idx, uint32_t perms)
{
printf(" allow %s %s:%s { %s };\n",
policydb->p_type_val_to_name[key->source_type
? key->source_type - 1 : idx],
key->target_type == key->source_type ? "self" :
policydb->p_type_val_to_name[key->target_type
? key->target_type - 1 : idx],
policydb->p_class_val_to_name[key->target_class - 1],
sepol_av_to_string
(policydb, key->target_class, perms));
}
int load_policy(char *filename, policydb_t * policydb, struct policy_file *pf)
{
int fd;
struct stat sb;
void *map;
int ret;
fd = open(filename, O_RDONLY);
if (fd < 0) {
fprintf(stderr, "Can't open '%s': %s\n", filename, strerror(errno));
return 1;
}
if (fstat(fd, &sb) < 0) {
fprintf(stderr, "Can't stat '%s': %s\n", filename, strerror(errno));
close(fd);
return 1;
}
map = mmap(NULL, sb.st_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
if (map == MAP_FAILED) {
fprintf(stderr, "Can't mmap '%s': %s\n", filename, strerror(errno));
close(fd);
return 1;
}
policy_file_init(pf);
pf->type = PF_USE_MEMORY;
pf->data = map;
pf->len = sb.st_size;
if (policydb_init(policydb)) {
fprintf(stderr, "Could not initialize policydb!\n");
close(fd);
munmap(map, sb.st_size);
return 1;
}
ret = policydb_read(policydb, pf, 0);
if (ret) {
fprintf(stderr, "error(s) encountered while parsing configuration\n");
close(fd);
munmap(map, sb.st_size);
return 1;
}
return 0;
}

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#ifndef UTILS_H
#define UTILS_H
#include <stdbool.h>
#include <stdint.h>
#include <sepol/policydb/avtab.h>
#include <sepol/policydb/policydb.h>
extern bool USAGE_ERROR;
void display_allow(policydb_t *policydb, avtab_key_t *key, int idx, uint32_t perms);
int load_policy(char *filename, policydb_t * policydb, struct policy_file *pf);
#endif /* UTILS_H */