kernel_optimize_test/security/selinux/ss/policydb.c
Eric Paris 9dc9978084 selinux: introduce schedule points in policydb_destroy()
During the LSPP testing we found that it was possible for
policydb_destroy() to take 10+ seconds of kernel time to complete.
Basically all policydb_destroy() does is walk some (possibly long) lists
and free the memory it finds.  Turning off slab debugging config options
made the problem go away since the actual functions which took most of
the time were (as seen by oprofile)

> 121202   23.9879  .check_poison_obj
> 78247    15.4864  .check_slabp

were caused by that.  So I decided to also add some voluntary schedule
points in that code so config voluntary preempt would be enough to solve
the problem.  Something similar was done in places like
shmem_free_pages() when we have to walk a list of memory and free it.
This was tested by the LSPP group on the hardware which could reproduce
the problem just loading a new policy and was found to not trigger the
softlock detector.  It takes just as much processing time, but the
kernel doesn't spend all that time stuck doing one thing and never
scheduling.

Someday a better way to handle memory might make the time needed in this
function a lot less, but this fixes the current issue as it stands
today.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2007-07-11 22:52:23 -04:00

1907 lines
38 KiB
C

/*
* Implementation of the policy database.
*
* Author : Stephen Smalley, <sds@epoch.ncsc.mil>
*/
/*
* Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
*
* Support for enhanced MLS infrastructure.
*
* Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
*
* Added conditional policy language extensions
*
* Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
* Copyright (C) 2003 - 2004 Tresys Technology, LLC
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 2.
*/
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/errno.h>
#include "security.h"
#include "policydb.h"
#include "conditional.h"
#include "mls.h"
#define _DEBUG_HASHES
#ifdef DEBUG_HASHES
static char *symtab_name[SYM_NUM] = {
"common prefixes",
"classes",
"roles",
"types",
"users",
"bools",
"levels",
"categories",
};
#endif
int selinux_mls_enabled = 0;
static unsigned int symtab_sizes[SYM_NUM] = {
2,
32,
16,
512,
128,
16,
16,
16,
};
struct policydb_compat_info {
int version;
int sym_num;
int ocon_num;
};
/* These need to be updated if SYM_NUM or OCON_NUM changes */
static struct policydb_compat_info policydb_compat[] = {
{
.version = POLICYDB_VERSION_BASE,
.sym_num = SYM_NUM - 3,
.ocon_num = OCON_NUM - 1,
},
{
.version = POLICYDB_VERSION_BOOL,
.sym_num = SYM_NUM - 2,
.ocon_num = OCON_NUM - 1,
},
{
.version = POLICYDB_VERSION_IPV6,
.sym_num = SYM_NUM - 2,
.ocon_num = OCON_NUM,
},
{
.version = POLICYDB_VERSION_NLCLASS,
.sym_num = SYM_NUM - 2,
.ocon_num = OCON_NUM,
},
{
.version = POLICYDB_VERSION_MLS,
.sym_num = SYM_NUM,
.ocon_num = OCON_NUM,
},
{
.version = POLICYDB_VERSION_AVTAB,
.sym_num = SYM_NUM,
.ocon_num = OCON_NUM,
},
{
.version = POLICYDB_VERSION_RANGETRANS,
.sym_num = SYM_NUM,
.ocon_num = OCON_NUM,
},
};
static struct policydb_compat_info *policydb_lookup_compat(int version)
{
int i;
struct policydb_compat_info *info = NULL;
for (i = 0; i < ARRAY_SIZE(policydb_compat); i++) {
if (policydb_compat[i].version == version) {
info = &policydb_compat[i];
break;
}
}
return info;
}
/*
* Initialize the role table.
*/
static int roles_init(struct policydb *p)
{
char *key = NULL;
int rc;
struct role_datum *role;
role = kzalloc(sizeof(*role), GFP_KERNEL);
if (!role) {
rc = -ENOMEM;
goto out;
}
role->value = ++p->p_roles.nprim;
if (role->value != OBJECT_R_VAL) {
rc = -EINVAL;
goto out_free_role;
}
key = kmalloc(strlen(OBJECT_R)+1,GFP_KERNEL);
if (!key) {
rc = -ENOMEM;
goto out_free_role;
}
strcpy(key, OBJECT_R);
rc = hashtab_insert(p->p_roles.table, key, role);
if (rc)
goto out_free_key;
out:
return rc;
out_free_key:
kfree(key);
out_free_role:
kfree(role);
goto out;
}
/*
* Initialize a policy database structure.
*/
static int policydb_init(struct policydb *p)
{
int i, rc;
memset(p, 0, sizeof(*p));
for (i = 0; i < SYM_NUM; i++) {
rc = symtab_init(&p->symtab[i], symtab_sizes[i]);
if (rc)
goto out_free_symtab;
}
rc = avtab_init(&p->te_avtab);
if (rc)
goto out_free_symtab;
rc = roles_init(p);
if (rc)
goto out_free_avtab;
rc = cond_policydb_init(p);
if (rc)
goto out_free_avtab;
out:
return rc;
out_free_avtab:
avtab_destroy(&p->te_avtab);
out_free_symtab:
for (i = 0; i < SYM_NUM; i++)
hashtab_destroy(p->symtab[i].table);
goto out;
}
/*
* The following *_index functions are used to
* define the val_to_name and val_to_struct arrays
* in a policy database structure. The val_to_name
* arrays are used when converting security context
* structures into string representations. The
* val_to_struct arrays are used when the attributes
* of a class, role, or user are needed.
*/
static int common_index(void *key, void *datum, void *datap)
{
struct policydb *p;
struct common_datum *comdatum;
comdatum = datum;
p = datap;
if (!comdatum->value || comdatum->value > p->p_commons.nprim)
return -EINVAL;
p->p_common_val_to_name[comdatum->value - 1] = key;
return 0;
}
static int class_index(void *key, void *datum, void *datap)
{
struct policydb *p;
struct class_datum *cladatum;
cladatum = datum;
p = datap;
if (!cladatum->value || cladatum->value > p->p_classes.nprim)
return -EINVAL;
p->p_class_val_to_name[cladatum->value - 1] = key;
p->class_val_to_struct[cladatum->value - 1] = cladatum;
return 0;
}
static int role_index(void *key, void *datum, void *datap)
{
struct policydb *p;
struct role_datum *role;
role = datum;
p = datap;
if (!role->value || role->value > p->p_roles.nprim)
return -EINVAL;
p->p_role_val_to_name[role->value - 1] = key;
p->role_val_to_struct[role->value - 1] = role;
return 0;
}
static int type_index(void *key, void *datum, void *datap)
{
struct policydb *p;
struct type_datum *typdatum;
typdatum = datum;
p = datap;
if (typdatum->primary) {
if (!typdatum->value || typdatum->value > p->p_types.nprim)
return -EINVAL;
p->p_type_val_to_name[typdatum->value - 1] = key;
}
return 0;
}
static int user_index(void *key, void *datum, void *datap)
{
struct policydb *p;
struct user_datum *usrdatum;
usrdatum = datum;
p = datap;
if (!usrdatum->value || usrdatum->value > p->p_users.nprim)
return -EINVAL;
p->p_user_val_to_name[usrdatum->value - 1] = key;
p->user_val_to_struct[usrdatum->value - 1] = usrdatum;
return 0;
}
static int sens_index(void *key, void *datum, void *datap)
{
struct policydb *p;
struct level_datum *levdatum;
levdatum = datum;
p = datap;
if (!levdatum->isalias) {
if (!levdatum->level->sens ||
levdatum->level->sens > p->p_levels.nprim)
return -EINVAL;
p->p_sens_val_to_name[levdatum->level->sens - 1] = key;
}
return 0;
}
static int cat_index(void *key, void *datum, void *datap)
{
struct policydb *p;
struct cat_datum *catdatum;
catdatum = datum;
p = datap;
if (!catdatum->isalias) {
if (!catdatum->value || catdatum->value > p->p_cats.nprim)
return -EINVAL;
p->p_cat_val_to_name[catdatum->value - 1] = key;
}
return 0;
}
static int (*index_f[SYM_NUM]) (void *key, void *datum, void *datap) =
{
common_index,
class_index,
role_index,
type_index,
user_index,
cond_index_bool,
sens_index,
cat_index,
};
/*
* Define the common val_to_name array and the class
* val_to_name and val_to_struct arrays in a policy
* database structure.
*
* Caller must clean up upon failure.
*/
static int policydb_index_classes(struct policydb *p)
{
int rc;
p->p_common_val_to_name =
kmalloc(p->p_commons.nprim * sizeof(char *), GFP_KERNEL);
if (!p->p_common_val_to_name) {
rc = -ENOMEM;
goto out;
}
rc = hashtab_map(p->p_commons.table, common_index, p);
if (rc)
goto out;
p->class_val_to_struct =
kmalloc(p->p_classes.nprim * sizeof(*(p->class_val_to_struct)), GFP_KERNEL);
if (!p->class_val_to_struct) {
rc = -ENOMEM;
goto out;
}
p->p_class_val_to_name =
kmalloc(p->p_classes.nprim * sizeof(char *), GFP_KERNEL);
if (!p->p_class_val_to_name) {
rc = -ENOMEM;
goto out;
}
rc = hashtab_map(p->p_classes.table, class_index, p);
out:
return rc;
}
#ifdef DEBUG_HASHES
static void symtab_hash_eval(struct symtab *s)
{
int i;
for (i = 0; i < SYM_NUM; i++) {
struct hashtab *h = s[i].table;
struct hashtab_info info;
hashtab_stat(h, &info);
printk(KERN_DEBUG "%s: %d entries and %d/%d buckets used, "
"longest chain length %d\n", symtab_name[i], h->nel,
info.slots_used, h->size, info.max_chain_len);
}
}
#endif
/*
* Define the other val_to_name and val_to_struct arrays
* in a policy database structure.
*
* Caller must clean up on failure.
*/
static int policydb_index_others(struct policydb *p)
{
int i, rc = 0;
printk(KERN_DEBUG "security: %d users, %d roles, %d types, %d bools",
p->p_users.nprim, p->p_roles.nprim, p->p_types.nprim, p->p_bools.nprim);
if (selinux_mls_enabled)
printk(", %d sens, %d cats", p->p_levels.nprim,
p->p_cats.nprim);
printk("\n");
printk(KERN_DEBUG "security: %d classes, %d rules\n",
p->p_classes.nprim, p->te_avtab.nel);
#ifdef DEBUG_HASHES
avtab_hash_eval(&p->te_avtab, "rules");
symtab_hash_eval(p->symtab);
#endif
p->role_val_to_struct =
kmalloc(p->p_roles.nprim * sizeof(*(p->role_val_to_struct)),
GFP_KERNEL);
if (!p->role_val_to_struct) {
rc = -ENOMEM;
goto out;
}
p->user_val_to_struct =
kmalloc(p->p_users.nprim * sizeof(*(p->user_val_to_struct)),
GFP_KERNEL);
if (!p->user_val_to_struct) {
rc = -ENOMEM;
goto out;
}
if (cond_init_bool_indexes(p)) {
rc = -ENOMEM;
goto out;
}
for (i = SYM_ROLES; i < SYM_NUM; i++) {
p->sym_val_to_name[i] =
kmalloc(p->symtab[i].nprim * sizeof(char *), GFP_KERNEL);
if (!p->sym_val_to_name[i]) {
rc = -ENOMEM;
goto out;
}
rc = hashtab_map(p->symtab[i].table, index_f[i], p);
if (rc)
goto out;
}
out:
return rc;
}
/*
* The following *_destroy functions are used to
* free any memory allocated for each kind of
* symbol data in the policy database.
*/
static int perm_destroy(void *key, void *datum, void *p)
{
kfree(key);
kfree(datum);
return 0;
}
static int common_destroy(void *key, void *datum, void *p)
{
struct common_datum *comdatum;
kfree(key);
comdatum = datum;
hashtab_map(comdatum->permissions.table, perm_destroy, NULL);
hashtab_destroy(comdatum->permissions.table);
kfree(datum);
return 0;
}
static int cls_destroy(void *key, void *datum, void *p)
{
struct class_datum *cladatum;
struct constraint_node *constraint, *ctemp;
struct constraint_expr *e, *etmp;
kfree(key);
cladatum = datum;
hashtab_map(cladatum->permissions.table, perm_destroy, NULL);
hashtab_destroy(cladatum->permissions.table);
constraint = cladatum->constraints;
while (constraint) {
e = constraint->expr;
while (e) {
ebitmap_destroy(&e->names);
etmp = e;
e = e->next;
kfree(etmp);
}
ctemp = constraint;
constraint = constraint->next;
kfree(ctemp);
}
constraint = cladatum->validatetrans;
while (constraint) {
e = constraint->expr;
while (e) {
ebitmap_destroy(&e->names);
etmp = e;
e = e->next;
kfree(etmp);
}
ctemp = constraint;
constraint = constraint->next;
kfree(ctemp);
}
kfree(cladatum->comkey);
kfree(datum);
return 0;
}
static int role_destroy(void *key, void *datum, void *p)
{
struct role_datum *role;
kfree(key);
role = datum;
ebitmap_destroy(&role->dominates);
ebitmap_destroy(&role->types);
kfree(datum);
return 0;
}
static int type_destroy(void *key, void *datum, void *p)
{
kfree(key);
kfree(datum);
return 0;
}
static int user_destroy(void *key, void *datum, void *p)
{
struct user_datum *usrdatum;
kfree(key);
usrdatum = datum;
ebitmap_destroy(&usrdatum->roles);
ebitmap_destroy(&usrdatum->range.level[0].cat);
ebitmap_destroy(&usrdatum->range.level[1].cat);
ebitmap_destroy(&usrdatum->dfltlevel.cat);
kfree(datum);
return 0;
}
static int sens_destroy(void *key, void *datum, void *p)
{
struct level_datum *levdatum;
kfree(key);
levdatum = datum;
ebitmap_destroy(&levdatum->level->cat);
kfree(levdatum->level);
kfree(datum);
return 0;
}
static int cat_destroy(void *key, void *datum, void *p)
{
kfree(key);
kfree(datum);
return 0;
}
static int (*destroy_f[SYM_NUM]) (void *key, void *datum, void *datap) =
{
common_destroy,
cls_destroy,
role_destroy,
type_destroy,
user_destroy,
cond_destroy_bool,
sens_destroy,
cat_destroy,
};
static void ocontext_destroy(struct ocontext *c, int i)
{
context_destroy(&c->context[0]);
context_destroy(&c->context[1]);
if (i == OCON_ISID || i == OCON_FS ||
i == OCON_NETIF || i == OCON_FSUSE)
kfree(c->u.name);
kfree(c);
}
/*
* Free any memory allocated by a policy database structure.
*/
void policydb_destroy(struct policydb *p)
{
struct ocontext *c, *ctmp;
struct genfs *g, *gtmp;
int i;
struct role_allow *ra, *lra = NULL;
struct role_trans *tr, *ltr = NULL;
struct range_trans *rt, *lrt = NULL;
for (i = 0; i < SYM_NUM; i++) {
cond_resched();
hashtab_map(p->symtab[i].table, destroy_f[i], NULL);
hashtab_destroy(p->symtab[i].table);
}
for (i = 0; i < SYM_NUM; i++)
kfree(p->sym_val_to_name[i]);
kfree(p->class_val_to_struct);
kfree(p->role_val_to_struct);
kfree(p->user_val_to_struct);
avtab_destroy(&p->te_avtab);
for (i = 0; i < OCON_NUM; i++) {
cond_resched();
c = p->ocontexts[i];
while (c) {
ctmp = c;
c = c->next;
ocontext_destroy(ctmp,i);
}
p->ocontexts[i] = NULL;
}
g = p->genfs;
while (g) {
cond_resched();
kfree(g->fstype);
c = g->head;
while (c) {
ctmp = c;
c = c->next;
ocontext_destroy(ctmp,OCON_FSUSE);
}
gtmp = g;
g = g->next;
kfree(gtmp);
}
p->genfs = NULL;
cond_policydb_destroy(p);
for (tr = p->role_tr; tr; tr = tr->next) {
cond_resched();
kfree(ltr);
ltr = tr;
}
kfree(ltr);
for (ra = p->role_allow; ra; ra = ra -> next) {
cond_resched();
kfree(lra);
lra = ra;
}
kfree(lra);
for (rt = p->range_tr; rt; rt = rt -> next) {
cond_resched();
if (lrt) {
ebitmap_destroy(&lrt->target_range.level[0].cat);
ebitmap_destroy(&lrt->target_range.level[1].cat);
kfree(lrt);
}
lrt = rt;
}
if (lrt) {
ebitmap_destroy(&lrt->target_range.level[0].cat);
ebitmap_destroy(&lrt->target_range.level[1].cat);
kfree(lrt);
}
if (p->type_attr_map) {
for (i = 0; i < p->p_types.nprim; i++)
ebitmap_destroy(&p->type_attr_map[i]);
}
kfree(p->type_attr_map);
return;
}
/*
* Load the initial SIDs specified in a policy database
* structure into a SID table.
*/
int policydb_load_isids(struct policydb *p, struct sidtab *s)
{
struct ocontext *head, *c;
int rc;
rc = sidtab_init(s);
if (rc) {
printk(KERN_ERR "security: out of memory on SID table init\n");
goto out;
}
head = p->ocontexts[OCON_ISID];
for (c = head; c; c = c->next) {
if (!c->context[0].user) {
printk(KERN_ERR "security: SID %s was never "
"defined.\n", c->u.name);
rc = -EINVAL;
goto out;
}
if (sidtab_insert(s, c->sid[0], &c->context[0])) {
printk(KERN_ERR "security: unable to load initial "
"SID %s.\n", c->u.name);
rc = -EINVAL;
goto out;
}
}
out:
return rc;
}
/*
* Return 1 if the fields in the security context
* structure `c' are valid. Return 0 otherwise.
*/
int policydb_context_isvalid(struct policydb *p, struct context *c)
{
struct role_datum *role;
struct user_datum *usrdatum;
if (!c->role || c->role > p->p_roles.nprim)
return 0;
if (!c->user || c->user > p->p_users.nprim)
return 0;
if (!c->type || c->type > p->p_types.nprim)
return 0;
if (c->role != OBJECT_R_VAL) {
/*
* Role must be authorized for the type.
*/
role = p->role_val_to_struct[c->role - 1];
if (!ebitmap_get_bit(&role->types,
c->type - 1))
/* role may not be associated with type */
return 0;
/*
* User must be authorized for the role.
*/
usrdatum = p->user_val_to_struct[c->user - 1];
if (!usrdatum)
return 0;
if (!ebitmap_get_bit(&usrdatum->roles,
c->role - 1))
/* user may not be associated with role */
return 0;
}
if (!mls_context_isvalid(p, c))
return 0;
return 1;
}
/*
* Read a MLS range structure from a policydb binary
* representation file.
*/
static int mls_read_range_helper(struct mls_range *r, void *fp)
{
__le32 buf[2];
u32 items;
int rc;
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto out;
items = le32_to_cpu(buf[0]);
if (items > ARRAY_SIZE(buf)) {
printk(KERN_ERR "security: mls: range overflow\n");
rc = -EINVAL;
goto out;
}
rc = next_entry(buf, fp, sizeof(u32) * items);
if (rc < 0) {
printk(KERN_ERR "security: mls: truncated range\n");
goto out;
}
r->level[0].sens = le32_to_cpu(buf[0]);
if (items > 1)
r->level[1].sens = le32_to_cpu(buf[1]);
else
r->level[1].sens = r->level[0].sens;
rc = ebitmap_read(&r->level[0].cat, fp);
if (rc) {
printk(KERN_ERR "security: mls: error reading low "
"categories\n");
goto out;
}
if (items > 1) {
rc = ebitmap_read(&r->level[1].cat, fp);
if (rc) {
printk(KERN_ERR "security: mls: error reading high "
"categories\n");
goto bad_high;
}
} else {
rc = ebitmap_cpy(&r->level[1].cat, &r->level[0].cat);
if (rc) {
printk(KERN_ERR "security: mls: out of memory\n");
goto bad_high;
}
}
rc = 0;
out:
return rc;
bad_high:
ebitmap_destroy(&r->level[0].cat);
goto out;
}
/*
* Read and validate a security context structure
* from a policydb binary representation file.
*/
static int context_read_and_validate(struct context *c,
struct policydb *p,
void *fp)
{
__le32 buf[3];
int rc;
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0) {
printk(KERN_ERR "security: context truncated\n");
goto out;
}
c->user = le32_to_cpu(buf[0]);
c->role = le32_to_cpu(buf[1]);
c->type = le32_to_cpu(buf[2]);
if (p->policyvers >= POLICYDB_VERSION_MLS) {
if (mls_read_range_helper(&c->range, fp)) {
printk(KERN_ERR "security: error reading MLS range of "
"context\n");
rc = -EINVAL;
goto out;
}
}
if (!policydb_context_isvalid(p, c)) {
printk(KERN_ERR "security: invalid security context\n");
context_destroy(c);
rc = -EINVAL;
}
out:
return rc;
}
/*
* The following *_read functions are used to
* read the symbol data from a policy database
* binary representation file.
*/
static int perm_read(struct policydb *p, struct hashtab *h, void *fp)
{
char *key = NULL;
struct perm_datum *perdatum;
int rc;
__le32 buf[2];
u32 len;
perdatum = kzalloc(sizeof(*perdatum), GFP_KERNEL);
if (!perdatum) {
rc = -ENOMEM;
goto out;
}
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
perdatum->value = le32_to_cpu(buf[1]);
key = kmalloc(len + 1,GFP_KERNEL);
if (!key) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(key, fp, len);
if (rc < 0)
goto bad;
key[len] = 0;
rc = hashtab_insert(h, key, perdatum);
if (rc)
goto bad;
out:
return rc;
bad:
perm_destroy(key, perdatum, NULL);
goto out;
}
static int common_read(struct policydb *p, struct hashtab *h, void *fp)
{
char *key = NULL;
struct common_datum *comdatum;
__le32 buf[4];
u32 len, nel;
int i, rc;
comdatum = kzalloc(sizeof(*comdatum), GFP_KERNEL);
if (!comdatum) {
rc = -ENOMEM;
goto out;
}
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
comdatum->value = le32_to_cpu(buf[1]);
rc = symtab_init(&comdatum->permissions, PERM_SYMTAB_SIZE);
if (rc)
goto bad;
comdatum->permissions.nprim = le32_to_cpu(buf[2]);
nel = le32_to_cpu(buf[3]);
key = kmalloc(len + 1,GFP_KERNEL);
if (!key) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(key, fp, len);
if (rc < 0)
goto bad;
key[len] = 0;
for (i = 0; i < nel; i++) {
rc = perm_read(p, comdatum->permissions.table, fp);
if (rc)
goto bad;
}
rc = hashtab_insert(h, key, comdatum);
if (rc)
goto bad;
out:
return rc;
bad:
common_destroy(key, comdatum, NULL);
goto out;
}
static int read_cons_helper(struct constraint_node **nodep, int ncons,
int allowxtarget, void *fp)
{
struct constraint_node *c, *lc;
struct constraint_expr *e, *le;
__le32 buf[3];
u32 nexpr;
int rc, i, j, depth;
lc = NULL;
for (i = 0; i < ncons; i++) {
c = kzalloc(sizeof(*c), GFP_KERNEL);
if (!c)
return -ENOMEM;
if (lc) {
lc->next = c;
} else {
*nodep = c;
}
rc = next_entry(buf, fp, (sizeof(u32) * 2));
if (rc < 0)
return rc;
c->permissions = le32_to_cpu(buf[0]);
nexpr = le32_to_cpu(buf[1]);
le = NULL;
depth = -1;
for (j = 0; j < nexpr; j++) {
e = kzalloc(sizeof(*e), GFP_KERNEL);
if (!e)
return -ENOMEM;
if (le) {
le->next = e;
} else {
c->expr = e;
}
rc = next_entry(buf, fp, (sizeof(u32) * 3));
if (rc < 0)
return rc;
e->expr_type = le32_to_cpu(buf[0]);
e->attr = le32_to_cpu(buf[1]);
e->op = le32_to_cpu(buf[2]);
switch (e->expr_type) {
case CEXPR_NOT:
if (depth < 0)
return -EINVAL;
break;
case CEXPR_AND:
case CEXPR_OR:
if (depth < 1)
return -EINVAL;
depth--;
break;
case CEXPR_ATTR:
if (depth == (CEXPR_MAXDEPTH - 1))
return -EINVAL;
depth++;
break;
case CEXPR_NAMES:
if (!allowxtarget && (e->attr & CEXPR_XTARGET))
return -EINVAL;
if (depth == (CEXPR_MAXDEPTH - 1))
return -EINVAL;
depth++;
if (ebitmap_read(&e->names, fp))
return -EINVAL;
break;
default:
return -EINVAL;
}
le = e;
}
if (depth != 0)
return -EINVAL;
lc = c;
}
return 0;
}
static int class_read(struct policydb *p, struct hashtab *h, void *fp)
{
char *key = NULL;
struct class_datum *cladatum;
__le32 buf[6];
u32 len, len2, ncons, nel;
int i, rc;
cladatum = kzalloc(sizeof(*cladatum), GFP_KERNEL);
if (!cladatum) {
rc = -ENOMEM;
goto out;
}
rc = next_entry(buf, fp, sizeof(u32)*6);
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
len2 = le32_to_cpu(buf[1]);
cladatum->value = le32_to_cpu(buf[2]);
rc = symtab_init(&cladatum->permissions, PERM_SYMTAB_SIZE);
if (rc)
goto bad;
cladatum->permissions.nprim = le32_to_cpu(buf[3]);
nel = le32_to_cpu(buf[4]);
ncons = le32_to_cpu(buf[5]);
key = kmalloc(len + 1,GFP_KERNEL);
if (!key) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(key, fp, len);
if (rc < 0)
goto bad;
key[len] = 0;
if (len2) {
cladatum->comkey = kmalloc(len2 + 1,GFP_KERNEL);
if (!cladatum->comkey) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(cladatum->comkey, fp, len2);
if (rc < 0)
goto bad;
cladatum->comkey[len2] = 0;
cladatum->comdatum = hashtab_search(p->p_commons.table,
cladatum->comkey);
if (!cladatum->comdatum) {
printk(KERN_ERR "security: unknown common %s\n",
cladatum->comkey);
rc = -EINVAL;
goto bad;
}
}
for (i = 0; i < nel; i++) {
rc = perm_read(p, cladatum->permissions.table, fp);
if (rc)
goto bad;
}
rc = read_cons_helper(&cladatum->constraints, ncons, 0, fp);
if (rc)
goto bad;
if (p->policyvers >= POLICYDB_VERSION_VALIDATETRANS) {
/* grab the validatetrans rules */
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
ncons = le32_to_cpu(buf[0]);
rc = read_cons_helper(&cladatum->validatetrans, ncons, 1, fp);
if (rc)
goto bad;
}
rc = hashtab_insert(h, key, cladatum);
if (rc)
goto bad;
rc = 0;
out:
return rc;
bad:
cls_destroy(key, cladatum, NULL);
goto out;
}
static int role_read(struct policydb *p, struct hashtab *h, void *fp)
{
char *key = NULL;
struct role_datum *role;
int rc;
__le32 buf[2];
u32 len;
role = kzalloc(sizeof(*role), GFP_KERNEL);
if (!role) {
rc = -ENOMEM;
goto out;
}
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
role->value = le32_to_cpu(buf[1]);
key = kmalloc(len + 1,GFP_KERNEL);
if (!key) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(key, fp, len);
if (rc < 0)
goto bad;
key[len] = 0;
rc = ebitmap_read(&role->dominates, fp);
if (rc)
goto bad;
rc = ebitmap_read(&role->types, fp);
if (rc)
goto bad;
if (strcmp(key, OBJECT_R) == 0) {
if (role->value != OBJECT_R_VAL) {
printk(KERN_ERR "Role %s has wrong value %d\n",
OBJECT_R, role->value);
rc = -EINVAL;
goto bad;
}
rc = 0;
goto bad;
}
rc = hashtab_insert(h, key, role);
if (rc)
goto bad;
out:
return rc;
bad:
role_destroy(key, role, NULL);
goto out;
}
static int type_read(struct policydb *p, struct hashtab *h, void *fp)
{
char *key = NULL;
struct type_datum *typdatum;
int rc;
__le32 buf[3];
u32 len;
typdatum = kzalloc(sizeof(*typdatum),GFP_KERNEL);
if (!typdatum) {
rc = -ENOMEM;
return rc;
}
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
typdatum->value = le32_to_cpu(buf[1]);
typdatum->primary = le32_to_cpu(buf[2]);
key = kmalloc(len + 1,GFP_KERNEL);
if (!key) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(key, fp, len);
if (rc < 0)
goto bad;
key[len] = 0;
rc = hashtab_insert(h, key, typdatum);
if (rc)
goto bad;
out:
return rc;
bad:
type_destroy(key, typdatum, NULL);
goto out;
}
/*
* Read a MLS level structure from a policydb binary
* representation file.
*/
static int mls_read_level(struct mls_level *lp, void *fp)
{
__le32 buf[1];
int rc;
memset(lp, 0, sizeof(*lp));
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0) {
printk(KERN_ERR "security: mls: truncated level\n");
goto bad;
}
lp->sens = le32_to_cpu(buf[0]);
if (ebitmap_read(&lp->cat, fp)) {
printk(KERN_ERR "security: mls: error reading level "
"categories\n");
goto bad;
}
return 0;
bad:
return -EINVAL;
}
static int user_read(struct policydb *p, struct hashtab *h, void *fp)
{
char *key = NULL;
struct user_datum *usrdatum;
int rc;
__le32 buf[2];
u32 len;
usrdatum = kzalloc(sizeof(*usrdatum), GFP_KERNEL);
if (!usrdatum) {
rc = -ENOMEM;
goto out;
}
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
usrdatum->value = le32_to_cpu(buf[1]);
key = kmalloc(len + 1,GFP_KERNEL);
if (!key) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(key, fp, len);
if (rc < 0)
goto bad;
key[len] = 0;
rc = ebitmap_read(&usrdatum->roles, fp);
if (rc)
goto bad;
if (p->policyvers >= POLICYDB_VERSION_MLS) {
rc = mls_read_range_helper(&usrdatum->range, fp);
if (rc)
goto bad;
rc = mls_read_level(&usrdatum->dfltlevel, fp);
if (rc)
goto bad;
}
rc = hashtab_insert(h, key, usrdatum);
if (rc)
goto bad;
out:
return rc;
bad:
user_destroy(key, usrdatum, NULL);
goto out;
}
static int sens_read(struct policydb *p, struct hashtab *h, void *fp)
{
char *key = NULL;
struct level_datum *levdatum;
int rc;
__le32 buf[2];
u32 len;
levdatum = kzalloc(sizeof(*levdatum), GFP_ATOMIC);
if (!levdatum) {
rc = -ENOMEM;
goto out;
}
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
levdatum->isalias = le32_to_cpu(buf[1]);
key = kmalloc(len + 1,GFP_ATOMIC);
if (!key) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(key, fp, len);
if (rc < 0)
goto bad;
key[len] = 0;
levdatum->level = kmalloc(sizeof(struct mls_level), GFP_ATOMIC);
if (!levdatum->level) {
rc = -ENOMEM;
goto bad;
}
if (mls_read_level(levdatum->level, fp)) {
rc = -EINVAL;
goto bad;
}
rc = hashtab_insert(h, key, levdatum);
if (rc)
goto bad;
out:
return rc;
bad:
sens_destroy(key, levdatum, NULL);
goto out;
}
static int cat_read(struct policydb *p, struct hashtab *h, void *fp)
{
char *key = NULL;
struct cat_datum *catdatum;
int rc;
__le32 buf[3];
u32 len;
catdatum = kzalloc(sizeof(*catdatum), GFP_ATOMIC);
if (!catdatum) {
rc = -ENOMEM;
goto out;
}
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
catdatum->value = le32_to_cpu(buf[1]);
catdatum->isalias = le32_to_cpu(buf[2]);
key = kmalloc(len + 1,GFP_ATOMIC);
if (!key) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(key, fp, len);
if (rc < 0)
goto bad;
key[len] = 0;
rc = hashtab_insert(h, key, catdatum);
if (rc)
goto bad;
out:
return rc;
bad:
cat_destroy(key, catdatum, NULL);
goto out;
}
static int (*read_f[SYM_NUM]) (struct policydb *p, struct hashtab *h, void *fp) =
{
common_read,
class_read,
role_read,
type_read,
user_read,
cond_read_bool,
sens_read,
cat_read,
};
extern int ss_initialized;
/*
* Read the configuration data from a policy database binary
* representation file into a policy database structure.
*/
int policydb_read(struct policydb *p, void *fp)
{
struct role_allow *ra, *lra;
struct role_trans *tr, *ltr;
struct ocontext *l, *c, *newc;
struct genfs *genfs_p, *genfs, *newgenfs;
int i, j, rc;
__le32 buf[8];
u32 len, len2, config, nprim, nel, nel2;
char *policydb_str;
struct policydb_compat_info *info;
struct range_trans *rt, *lrt;
config = 0;
rc = policydb_init(p);
if (rc)
goto out;
/* Read the magic number and string length. */
rc = next_entry(buf, fp, sizeof(u32)* 2);
if (rc < 0)
goto bad;
if (le32_to_cpu(buf[0]) != POLICYDB_MAGIC) {
printk(KERN_ERR "security: policydb magic number 0x%x does "
"not match expected magic number 0x%x\n",
le32_to_cpu(buf[0]), POLICYDB_MAGIC);
goto bad;
}
len = le32_to_cpu(buf[1]);
if (len != strlen(POLICYDB_STRING)) {
printk(KERN_ERR "security: policydb string length %d does not "
"match expected length %Zu\n",
len, strlen(POLICYDB_STRING));
goto bad;
}
policydb_str = kmalloc(len + 1,GFP_KERNEL);
if (!policydb_str) {
printk(KERN_ERR "security: unable to allocate memory for policydb "
"string of length %d\n", len);
rc = -ENOMEM;
goto bad;
}
rc = next_entry(policydb_str, fp, len);
if (rc < 0) {
printk(KERN_ERR "security: truncated policydb string identifier\n");
kfree(policydb_str);
goto bad;
}
policydb_str[len] = 0;
if (strcmp(policydb_str, POLICYDB_STRING)) {
printk(KERN_ERR "security: policydb string %s does not match "
"my string %s\n", policydb_str, POLICYDB_STRING);
kfree(policydb_str);
goto bad;
}
/* Done with policydb_str. */
kfree(policydb_str);
policydb_str = NULL;
/* Read the version, config, and table sizes. */
rc = next_entry(buf, fp, sizeof(u32)*4);
if (rc < 0)
goto bad;
p->policyvers = le32_to_cpu(buf[0]);
if (p->policyvers < POLICYDB_VERSION_MIN ||
p->policyvers > POLICYDB_VERSION_MAX) {
printk(KERN_ERR "security: policydb version %d does not match "
"my version range %d-%d\n",
le32_to_cpu(buf[0]), POLICYDB_VERSION_MIN, POLICYDB_VERSION_MAX);
goto bad;
}
if ((le32_to_cpu(buf[1]) & POLICYDB_CONFIG_MLS)) {
if (ss_initialized && !selinux_mls_enabled) {
printk(KERN_ERR "Cannot switch between non-MLS and MLS "
"policies\n");
goto bad;
}
selinux_mls_enabled = 1;
config |= POLICYDB_CONFIG_MLS;
if (p->policyvers < POLICYDB_VERSION_MLS) {
printk(KERN_ERR "security policydb version %d (MLS) "
"not backwards compatible\n", p->policyvers);
goto bad;
}
} else {
if (ss_initialized && selinux_mls_enabled) {
printk(KERN_ERR "Cannot switch between MLS and non-MLS "
"policies\n");
goto bad;
}
}
info = policydb_lookup_compat(p->policyvers);
if (!info) {
printk(KERN_ERR "security: unable to find policy compat info "
"for version %d\n", p->policyvers);
goto bad;
}
if (le32_to_cpu(buf[2]) != info->sym_num ||
le32_to_cpu(buf[3]) != info->ocon_num) {
printk(KERN_ERR "security: policydb table sizes (%d,%d) do "
"not match mine (%d,%d)\n", le32_to_cpu(buf[2]),
le32_to_cpu(buf[3]),
info->sym_num, info->ocon_num);
goto bad;
}
for (i = 0; i < info->sym_num; i++) {
rc = next_entry(buf, fp, sizeof(u32)*2);
if (rc < 0)
goto bad;
nprim = le32_to_cpu(buf[0]);
nel = le32_to_cpu(buf[1]);
for (j = 0; j < nel; j++) {
rc = read_f[i](p, p->symtab[i].table, fp);
if (rc)
goto bad;
}
p->symtab[i].nprim = nprim;
}
rc = avtab_read(&p->te_avtab, fp, p->policyvers);
if (rc)
goto bad;
if (p->policyvers >= POLICYDB_VERSION_BOOL) {
rc = cond_read_list(p, fp);
if (rc)
goto bad;
}
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
nel = le32_to_cpu(buf[0]);
ltr = NULL;
for (i = 0; i < nel; i++) {
tr = kzalloc(sizeof(*tr), GFP_KERNEL);
if (!tr) {
rc = -ENOMEM;
goto bad;
}
if (ltr) {
ltr->next = tr;
} else {
p->role_tr = tr;
}
rc = next_entry(buf, fp, sizeof(u32)*3);
if (rc < 0)
goto bad;
tr->role = le32_to_cpu(buf[0]);
tr->type = le32_to_cpu(buf[1]);
tr->new_role = le32_to_cpu(buf[2]);
ltr = tr;
}
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
nel = le32_to_cpu(buf[0]);
lra = NULL;
for (i = 0; i < nel; i++) {
ra = kzalloc(sizeof(*ra), GFP_KERNEL);
if (!ra) {
rc = -ENOMEM;
goto bad;
}
if (lra) {
lra->next = ra;
} else {
p->role_allow = ra;
}
rc = next_entry(buf, fp, sizeof(u32)*2);
if (rc < 0)
goto bad;
ra->role = le32_to_cpu(buf[0]);
ra->new_role = le32_to_cpu(buf[1]);
lra = ra;
}
rc = policydb_index_classes(p);
if (rc)
goto bad;
rc = policydb_index_others(p);
if (rc)
goto bad;
for (i = 0; i < info->ocon_num; i++) {
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
nel = le32_to_cpu(buf[0]);
l = NULL;
for (j = 0; j < nel; j++) {
c = kzalloc(sizeof(*c), GFP_KERNEL);
if (!c) {
rc = -ENOMEM;
goto bad;
}
if (l) {
l->next = c;
} else {
p->ocontexts[i] = c;
}
l = c;
rc = -EINVAL;
switch (i) {
case OCON_ISID:
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
c->sid[0] = le32_to_cpu(buf[0]);
rc = context_read_and_validate(&c->context[0], p, fp);
if (rc)
goto bad;
break;
case OCON_FS:
case OCON_NETIF:
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
c->u.name = kmalloc(len + 1,GFP_KERNEL);
if (!c->u.name) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(c->u.name, fp, len);
if (rc < 0)
goto bad;
c->u.name[len] = 0;
rc = context_read_and_validate(&c->context[0], p, fp);
if (rc)
goto bad;
rc = context_read_and_validate(&c->context[1], p, fp);
if (rc)
goto bad;
break;
case OCON_PORT:
rc = next_entry(buf, fp, sizeof(u32)*3);
if (rc < 0)
goto bad;
c->u.port.protocol = le32_to_cpu(buf[0]);
c->u.port.low_port = le32_to_cpu(buf[1]);
c->u.port.high_port = le32_to_cpu(buf[2]);
rc = context_read_and_validate(&c->context[0], p, fp);
if (rc)
goto bad;
break;
case OCON_NODE:
rc = next_entry(buf, fp, sizeof(u32)* 2);
if (rc < 0)
goto bad;
c->u.node.addr = le32_to_cpu(buf[0]);
c->u.node.mask = le32_to_cpu(buf[1]);
rc = context_read_and_validate(&c->context[0], p, fp);
if (rc)
goto bad;
break;
case OCON_FSUSE:
rc = next_entry(buf, fp, sizeof(u32)*2);
if (rc < 0)
goto bad;
c->v.behavior = le32_to_cpu(buf[0]);
if (c->v.behavior > SECURITY_FS_USE_NONE)
goto bad;
len = le32_to_cpu(buf[1]);
c->u.name = kmalloc(len + 1,GFP_KERNEL);
if (!c->u.name) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(c->u.name, fp, len);
if (rc < 0)
goto bad;
c->u.name[len] = 0;
rc = context_read_and_validate(&c->context[0], p, fp);
if (rc)
goto bad;
break;
case OCON_NODE6: {
int k;
rc = next_entry(buf, fp, sizeof(u32) * 8);
if (rc < 0)
goto bad;
for (k = 0; k < 4; k++)
c->u.node6.addr[k] = le32_to_cpu(buf[k]);
for (k = 0; k < 4; k++)
c->u.node6.mask[k] = le32_to_cpu(buf[k+4]);
if (context_read_and_validate(&c->context[0], p, fp))
goto bad;
break;
}
}
}
}
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
nel = le32_to_cpu(buf[0]);
genfs_p = NULL;
rc = -EINVAL;
for (i = 0; i < nel; i++) {
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
newgenfs = kzalloc(sizeof(*newgenfs), GFP_KERNEL);
if (!newgenfs) {
rc = -ENOMEM;
goto bad;
}
newgenfs->fstype = kmalloc(len + 1,GFP_KERNEL);
if (!newgenfs->fstype) {
rc = -ENOMEM;
kfree(newgenfs);
goto bad;
}
rc = next_entry(newgenfs->fstype, fp, len);
if (rc < 0) {
kfree(newgenfs->fstype);
kfree(newgenfs);
goto bad;
}
newgenfs->fstype[len] = 0;
for (genfs_p = NULL, genfs = p->genfs; genfs;
genfs_p = genfs, genfs = genfs->next) {
if (strcmp(newgenfs->fstype, genfs->fstype) == 0) {
printk(KERN_ERR "security: dup genfs "
"fstype %s\n", newgenfs->fstype);
kfree(newgenfs->fstype);
kfree(newgenfs);
goto bad;
}
if (strcmp(newgenfs->fstype, genfs->fstype) < 0)
break;
}
newgenfs->next = genfs;
if (genfs_p)
genfs_p->next = newgenfs;
else
p->genfs = newgenfs;
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
nel2 = le32_to_cpu(buf[0]);
for (j = 0; j < nel2; j++) {
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
newc = kzalloc(sizeof(*newc), GFP_KERNEL);
if (!newc) {
rc = -ENOMEM;
goto bad;
}
newc->u.name = kmalloc(len + 1,GFP_KERNEL);
if (!newc->u.name) {
rc = -ENOMEM;
goto bad_newc;
}
rc = next_entry(newc->u.name, fp, len);
if (rc < 0)
goto bad_newc;
newc->u.name[len] = 0;
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad_newc;
newc->v.sclass = le32_to_cpu(buf[0]);
if (context_read_and_validate(&newc->context[0], p, fp))
goto bad_newc;
for (l = NULL, c = newgenfs->head; c;
l = c, c = c->next) {
if (!strcmp(newc->u.name, c->u.name) &&
(!c->v.sclass || !newc->v.sclass ||
newc->v.sclass == c->v.sclass)) {
printk(KERN_ERR "security: dup genfs "
"entry (%s,%s)\n",
newgenfs->fstype, c->u.name);
goto bad_newc;
}
len = strlen(newc->u.name);
len2 = strlen(c->u.name);
if (len > len2)
break;
}
newc->next = c;
if (l)
l->next = newc;
else
newgenfs->head = newc;
}
}
if (p->policyvers >= POLICYDB_VERSION_MLS) {
int new_rangetr = p->policyvers >= POLICYDB_VERSION_RANGETRANS;
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
nel = le32_to_cpu(buf[0]);
lrt = NULL;
for (i = 0; i < nel; i++) {
rt = kzalloc(sizeof(*rt), GFP_KERNEL);
if (!rt) {
rc = -ENOMEM;
goto bad;
}
if (lrt)
lrt->next = rt;
else
p->range_tr = rt;
rc = next_entry(buf, fp, (sizeof(u32) * 2));
if (rc < 0)
goto bad;
rt->source_type = le32_to_cpu(buf[0]);
rt->target_type = le32_to_cpu(buf[1]);
if (new_rangetr) {
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
rt->target_class = le32_to_cpu(buf[0]);
} else
rt->target_class = SECCLASS_PROCESS;
rc = mls_read_range_helper(&rt->target_range, fp);
if (rc)
goto bad;
lrt = rt;
}
}
p->type_attr_map = kmalloc(p->p_types.nprim*sizeof(struct ebitmap), GFP_KERNEL);
if (!p->type_attr_map)
goto bad;
for (i = 0; i < p->p_types.nprim; i++) {
ebitmap_init(&p->type_attr_map[i]);
if (p->policyvers >= POLICYDB_VERSION_AVTAB) {
if (ebitmap_read(&p->type_attr_map[i], fp))
goto bad;
}
/* add the type itself as the degenerate case */
if (ebitmap_set_bit(&p->type_attr_map[i], i, 1))
goto bad;
}
rc = 0;
out:
return rc;
bad_newc:
ocontext_destroy(newc,OCON_FSUSE);
bad:
if (!rc)
rc = -EINVAL;
policydb_destroy(p);
goto out;
}