* Authors : Stephen Smalley, <sds@epoch.ncsc.mil>
* James Morris <jmorris@redhat.com>
*
- * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
+ * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2,
- * as published by the Free Software Foundation.
+ * 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
+ * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
* 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 "mls.h"
extern void selnl_notify_policyload(u32 seqno);
-extern int policydb_loaded_version;
+unsigned int policydb_loaded_version;
-static rwlock_t policy_rwlock = RW_LOCK_UNLOCKED;
+static DEFINE_RWLOCK(policy_rwlock);
#define POLICY_RDLOCK read_lock(&policy_rwlock)
#define POLICY_WRLOCK write_lock_irq(&policy_rwlock)
#define POLICY_RDUNLOCK read_unlock(&policy_rwlock)
#define LOAD_LOCK down(&load_sem)
#define LOAD_UNLOCK up(&load_sem)
-struct sidtab sidtab;
+static struct sidtab sidtab;
struct policydb policydb;
int ss_initialized = 0;
*/
static u32 latest_granting = 0;
+/* Forward declaration. */
+static int context_struct_to_string(struct context *context, char **scontext,
+ u32 *scontext_len);
+
/*
* Return the boolean value of a constraint expression
* when it is applied to the specified source and target
* security contexts.
+ *
+ * xcontext is a special beast... It is used by the validatetrans rules
+ * only. For these rules, scontext is the context before the transition,
+ * tcontext is the context after the transition, and xcontext is the context
+ * of the process performing the transition. All other callers of
+ * constraint_expr_eval should pass in NULL for xcontext.
*/
static int constraint_expr_eval(struct context *scontext,
struct context *tcontext,
+ struct context *xcontext,
struct constraint_expr *cexpr)
{
u32 val1, val2;
struct context *c;
struct role_datum *r1, *r2;
+ struct mls_level *l1, *l2;
struct constraint_expr *e;
int s[CEXPR_MAXDEPTH];
int sp = -1;
break;
}
break;
+ case CEXPR_L1L2:
+ l1 = &(scontext->range.level[0]);
+ l2 = &(tcontext->range.level[0]);
+ goto mls_ops;
+ case CEXPR_L1H2:
+ l1 = &(scontext->range.level[0]);
+ l2 = &(tcontext->range.level[1]);
+ goto mls_ops;
+ case CEXPR_H1L2:
+ l1 = &(scontext->range.level[1]);
+ l2 = &(tcontext->range.level[0]);
+ goto mls_ops;
+ case CEXPR_H1H2:
+ l1 = &(scontext->range.level[1]);
+ l2 = &(tcontext->range.level[1]);
+ goto mls_ops;
+ case CEXPR_L1H1:
+ l1 = &(scontext->range.level[0]);
+ l2 = &(scontext->range.level[1]);
+ goto mls_ops;
+ case CEXPR_L2H2:
+ l1 = &(tcontext->range.level[0]);
+ l2 = &(tcontext->range.level[1]);
+ goto mls_ops;
+mls_ops:
+ switch (e->op) {
+ case CEXPR_EQ:
+ s[++sp] = mls_level_eq(l1, l2);
+ continue;
+ case CEXPR_NEQ:
+ s[++sp] = !mls_level_eq(l1, l2);
+ continue;
+ case CEXPR_DOM:
+ s[++sp] = mls_level_dom(l1, l2);
+ continue;
+ case CEXPR_DOMBY:
+ s[++sp] = mls_level_dom(l2, l1);
+ continue;
+ case CEXPR_INCOMP:
+ s[++sp] = mls_level_incomp(l2, l1);
+ continue;
+ default:
+ BUG();
+ return 0;
+ }
+ break;
default:
BUG();
return 0;
c = scontext;
if (e->attr & CEXPR_TARGET)
c = tcontext;
+ else if (e->attr & CEXPR_XTARGET) {
+ c = xcontext;
+ if (!c) {
+ BUG();
+ return 0;
+ }
+ }
if (e->attr & CEXPR_USER)
val1 = c->user;
else if (e->attr & CEXPR_ROLE)
struct constraint_node *constraint;
struct role_allow *ra;
struct avtab_key avkey;
- struct avtab_datum *avdatum;
+ struct avtab_node *node;
struct class_datum *tclass_datum;
+ struct ebitmap *sattr, *tattr;
+ struct ebitmap_node *snode, *tnode;
+ unsigned int i, j;
/*
* Remap extended Netlink classes for old policy versions.
* If a specific type enforcement rule was defined for
* this permission check, then use it.
*/
- avkey.source_type = scontext->type;
- avkey.target_type = tcontext->type;
avkey.target_class = tclass;
- avdatum = avtab_search(&policydb.te_avtab, &avkey, AVTAB_AV);
- if (avdatum) {
- if (avdatum->specified & AVTAB_ALLOWED)
- avd->allowed = avtab_allowed(avdatum);
- if (avdatum->specified & AVTAB_AUDITDENY)
- avd->auditdeny = avtab_auditdeny(avdatum);
- if (avdatum->specified & AVTAB_AUDITALLOW)
- avd->auditallow = avtab_auditallow(avdatum);
- }
+ avkey.specified = AVTAB_AV;
+ sattr = &policydb.type_attr_map[scontext->type - 1];
+ tattr = &policydb.type_attr_map[tcontext->type - 1];
+ 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;
+ for (node = avtab_search_node(&policydb.te_avtab, &avkey);
+ node != NULL;
+ node = avtab_search_node_next(node, avkey.specified)) {
+ if (node->key.specified == AVTAB_ALLOWED)
+ avd->allowed |= node->datum.data;
+ else if (node->key.specified == AVTAB_AUDITALLOW)
+ avd->auditallow |= node->datum.data;
+ else if (node->key.specified == AVTAB_AUDITDENY)
+ avd->auditdeny &= node->datum.data;
+ }
- /* Check conditional av table for additional permissions */
- cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);
+ /* Check conditional av table for additional permissions */
+ cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);
- /*
- * Remove any permissions prohibited by the MLS policy.
- */
- mls_compute_av(scontext, tcontext, tclass_datum, &avd->allowed);
+ }
+ }
/*
- * Remove any permissions prohibited by a constraint.
+ * Remove any permissions prohibited by a constraint (this includes
+ * the MLS policy).
*/
constraint = tclass_datum->constraints;
while (constraint) {
if ((constraint->permissions & (avd->allowed)) &&
- !constraint_expr_eval(scontext, tcontext,
+ !constraint_expr_eval(scontext, tcontext, NULL,
constraint->expr)) {
avd->allowed = (avd->allowed) & ~(constraint->permissions);
}
* pair.
*/
if (tclass == SECCLASS_PROCESS &&
- (avd->allowed & PROCESS__TRANSITION) &&
+ (avd->allowed & (PROCESS__TRANSITION | PROCESS__DYNTRANSITION)) &&
scontext->role != tcontext->role) {
for (ra = policydb.role_allow; ra; ra = ra->next) {
if (scontext->role == ra->role &&
break;
}
if (!ra)
- avd->allowed = (avd->allowed) & ~(PROCESS__TRANSITION);
+ avd->allowed = (avd->allowed) & ~(PROCESS__TRANSITION |
+ PROCESS__DYNTRANSITION);
}
return 0;
}
+static int security_validtrans_handle_fail(struct context *ocontext,
+ struct context *ncontext,
+ struct context *tcontext,
+ u16 tclass)
+{
+ char *o = NULL, *n = NULL, *t = NULL;
+ u32 olen, nlen, tlen;
+
+ if (context_struct_to_string(ocontext, &o, &olen) < 0)
+ goto out;
+ if (context_struct_to_string(ncontext, &n, &nlen) < 0)
+ goto out;
+ if (context_struct_to_string(tcontext, &t, &tlen) < 0)
+ goto out;
+ audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
+ "security_validate_transition: denied for"
+ " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
+ o, n, t, policydb.p_class_val_to_name[tclass-1]);
+out:
+ kfree(o);
+ kfree(n);
+ kfree(t);
+
+ if (!selinux_enforcing)
+ return 0;
+ return -EPERM;
+}
+
+int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
+ u16 tclass)
+{
+ struct context *ocontext;
+ struct context *ncontext;
+ struct context *tcontext;
+ struct class_datum *tclass_datum;
+ struct constraint_node *constraint;
+ int rc = 0;
+
+ if (!ss_initialized)
+ return 0;
+
+ POLICY_RDLOCK;
+
+ /*
+ * Remap extended Netlink classes for old policy versions.
+ * Do this here rather than socket_type_to_security_class()
+ * in case a newer policy version is loaded, allowing sockets
+ * to remain in the correct class.
+ */
+ if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
+ if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
+ tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
+ tclass = SECCLASS_NETLINK_SOCKET;
+
+ if (!tclass || tclass > policydb.p_classes.nprim) {
+ printk(KERN_ERR "security_validate_transition: "
+ "unrecognized class %d\n", tclass);
+ rc = -EINVAL;
+ goto out;
+ }
+ tclass_datum = policydb.class_val_to_struct[tclass - 1];
+
+ ocontext = sidtab_search(&sidtab, oldsid);
+ if (!ocontext) {
+ printk(KERN_ERR "security_validate_transition: "
+ " unrecognized SID %d\n", oldsid);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ ncontext = sidtab_search(&sidtab, newsid);
+ if (!ncontext) {
+ printk(KERN_ERR "security_validate_transition: "
+ " unrecognized SID %d\n", newsid);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ tcontext = sidtab_search(&sidtab, tasksid);
+ if (!tcontext) {
+ printk(KERN_ERR "security_validate_transition: "
+ " unrecognized SID %d\n", tasksid);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ constraint = tclass_datum->validatetrans;
+ while (constraint) {
+ if (!constraint_expr_eval(ocontext, ncontext, tcontext,
+ constraint->expr)) {
+ rc = security_validtrans_handle_fail(ocontext, ncontext,
+ tcontext, tclass);
+ goto out;
+ }
+ constraint = constraint->next;
+ }
+
+out:
+ POLICY_RDUNLOCK;
+ return rc;
+}
+
/**
* security_compute_av - Compute access vector decisions.
* @ssid: source security identifier
int rc = 0;
if (!ss_initialized) {
- avd->allowed = requested;
- avd->decided = requested;
+ avd->allowed = 0xffffffff;
+ avd->decided = 0xffffffff;
avd->auditallow = 0;
avd->auditdeny = 0xffffffff;
avd->seqno = latest_granting;
* to point to this string and set `*scontext_len' to
* the length of the string.
*/
-int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
+static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
{
char *scontextp;
*scontext_len += mls_compute_context_len(context);
/* Allocate space for the context; caller must free this space. */
- scontextp = kmalloc(*scontext_len+1,GFP_ATOMIC);
+ scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
if (!scontextp) {
return -ENOMEM;
}
/*
* Copy the user name, role name and type name into the context.
*/
- sprintf(scontextp, "%s:%s:%s:",
+ sprintf(scontextp, "%s:%s:%s",
policydb.p_user_val_to_name[context->user - 1],
policydb.p_role_val_to_name[context->role - 1],
policydb.p_type_val_to_name[context->type - 1]);
scontextp += strlen(policydb.p_user_val_to_name[context->user - 1]) +
1 + strlen(policydb.p_role_val_to_name[context->role - 1]) +
- 1 + strlen(policydb.p_type_val_to_name[context->type - 1]) + 1;
+ 1 + strlen(policydb.p_type_val_to_name[context->type - 1]);
mls_sid_to_context(context, &scontextp);
- scontextp--;
*scontextp = 0;
return 0;
*scontext_len = strlen(initial_sid_to_string[sid]) + 1;
scontextp = kmalloc(*scontext_len,GFP_ATOMIC);
+ if (!scontextp) {
+ rc = -ENOMEM;
+ goto out;
+ }
strcpy(scontextp, initial_sid_to_string[sid]);
*scontext = scontextp;
goto out;
}
-/**
- * security_context_to_sid - Obtain a SID for a given security context.
- * @scontext: security context
- * @scontext_len: length in bytes
- * @sid: security identifier, SID
- *
- * Obtains a SID associated with the security context that
- * has the string representation specified by @scontext.
- * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
- * memory is available, or 0 on success.
- */
-int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid)
+static int security_context_to_sid_core(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
{
char *scontext2;
struct context context;
context.type = typdatum->value;
- rc = mls_context_to_sid(oldc, &p, &context);
+ rc = mls_context_to_sid(oldc, &p, &context, &sidtab, def_sid);
if (rc)
goto out_unlock;
return rc;
}
+/**
+ * security_context_to_sid - Obtain a SID for a given security context.
+ * @scontext: security context
+ * @scontext_len: length in bytes
+ * @sid: security identifier, SID
+ *
+ * Obtains a SID associated with the security context that
+ * has the string representation specified by @scontext.
+ * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
+ * memory is available, or 0 on success.
+ */
+int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid)
+{
+ return security_context_to_sid_core(scontext, scontext_len,
+ sid, SECSID_NULL);
+}
+
+/**
+ * security_context_to_sid_default - Obtain a SID for a given security context,
+ * falling back to specified default if needed.
+ *
+ * @scontext: security context
+ * @scontext_len: length in bytes
+ * @sid: security identifier, SID
+ * @def_sid: default SID to assign on errror
+ *
+ * Obtains a SID associated with the security context that
+ * has the string representation specified by @scontext.
+ * The default SID is passed to the MLS layer to be used to allow
+ * kernel labeling of the MLS field if the MLS field is not present
+ * (for upgrading to MLS without full relabel).
+ * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
+ * memory is available, or 0 on success.
+ */
+int security_context_to_sid_default(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
+{
+ return security_context_to_sid_core(scontext, scontext_len,
+ sid, def_sid);
+}
+
static int compute_sid_handle_invalid_context(
struct context *scontext,
struct context *tcontext,
goto out;
if (context_struct_to_string(newcontext, &n, &nlen) < 0)
goto out;
- audit_log(current->audit_context,
+ audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
"security_compute_sid: invalid context %s"
" for scontext=%s"
" tcontext=%s"
struct avtab_key avkey;
struct avtab_datum *avdatum;
struct avtab_node *node;
- unsigned int type_change = 0;
int rc = 0;
if (!ss_initialized) {
avkey.source_type = scontext->type;
avkey.target_type = tcontext->type;
avkey.target_class = tclass;
- avdatum = avtab_search(&policydb.te_avtab, &avkey, AVTAB_TYPE);
+ avkey.specified = specified;
+ avdatum = avtab_search(&policydb.te_avtab, &avkey);
/* If no permanent rule, also check for enabled conditional rules */
if(!avdatum) {
- node = avtab_search_node(&policydb.te_cond_avtab, &avkey, specified);
+ node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
for (; node != NULL; node = avtab_search_node_next(node, specified)) {
- if (node->datum.specified & AVTAB_ENABLED) {
+ if (node->key.specified & AVTAB_ENABLED) {
avdatum = &node->datum;
break;
}
}
}
- type_change = (avdatum && (avdatum->specified & specified));
- if (type_change) {
+ if (avdatum) {
/* Use the type from the type transition/member/change rule. */
- switch (specified) {
- case AVTAB_TRANSITION:
- newcontext.type = avtab_transition(avdatum);
- break;
- case AVTAB_MEMBER:
- newcontext.type = avtab_member(avdatum);
- break;
- case AVTAB_CHANGE:
- newcontext.type = avtab_change(avdatum);
- break;
- }
+ newcontext.type = avdatum->data;
}
/* Check for class-specific changes. */
}
}
}
-
- if (!type_change && !roletr) {
- /* No change in process role or type. */
- *out_sid = ssid;
- goto out_unlock;
-
- }
break;
default:
- if (!type_change &&
- (newcontext.user == tcontext->user) &&
- mls_context_cmp(scontext, tcontext)) {
- /* No change in object type, owner,
- or MLS attributes. */
- *out_sid = tsid;
- goto out_unlock;
- }
break;
}
avtab_cache_destroy();
return -EINVAL;
}
+ policydb_loaded_version = policydb.policyvers;
ss_initialized = 1;
-
+ seqno = ++latest_granting;
LOAD_UNLOCK;
selinux_complete_init();
+ avc_ss_reset(seqno);
+ selnl_notify_policyload(seqno);
return 0;
}
memcpy(&policydb, &newpolicydb, sizeof policydb);
sidtab_set(&sidtab, &newsidtab);
seqno = ++latest_granting;
-
+ policydb_loaded_version = policydb.policyvers;
POLICY_WRUNLOCK;
LOAD_UNLOCK;
struct user_datum *user;
struct role_datum *role;
struct av_decision avd;
+ struct ebitmap_node *rnode, *tnode;
int rc = 0, i, j;
if (!ss_initialized) {
}
usercon.user = user->value;
- mysids = kmalloc(maxnel*sizeof(*mysids), GFP_ATOMIC);
+ mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
if (!mysids) {
rc = -ENOMEM;
goto out_unlock;
}
- memset(mysids, 0, maxnel*sizeof(*mysids));
- for (i = ebitmap_startbit(&user->roles); i < ebitmap_length(&user->roles); i++) {
- if (!ebitmap_get_bit(&user->roles, i))
+ ebitmap_for_each_bit(&user->roles, rnode, i) {
+ if (!ebitmap_node_get_bit(rnode, i))
continue;
role = policydb.role_val_to_struct[i];
usercon.role = i+1;
- for (j = ebitmap_startbit(&role->types); j < ebitmap_length(&role->types); j++) {
- if (!ebitmap_get_bit(&role->types, j))
+ ebitmap_for_each_bit(&role->types, tnode, j) {
+ if (!ebitmap_node_get_bit(tnode, j))
continue;
usercon.type = j+1;
- mls_for_user_ranges(user,usercon) {
- rc = context_struct_compute_av(fromcon, &usercon,
- SECCLASS_PROCESS,
- PROCESS__TRANSITION,
- &avd);
- if (rc || !(avd.allowed & PROCESS__TRANSITION))
- continue;
- rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
- if (rc) {
+
+ if (mls_setup_user_range(fromcon, user, &usercon))
+ continue;
+
+ rc = context_struct_compute_av(fromcon, &usercon,
+ SECCLASS_PROCESS,
+ PROCESS__TRANSITION,
+ &avd);
+ if (rc || !(avd.allowed & PROCESS__TRANSITION))
+ continue;
+ rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
+ if (rc) {
+ kfree(mysids);
+ goto out_unlock;
+ }
+ if (mynel < maxnel) {
+ mysids[mynel++] = sid;
+ } else {
+ maxnel += SIDS_NEL;
+ mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
+ if (!mysids2) {
+ rc = -ENOMEM;
kfree(mysids);
goto out_unlock;
}
- if (mynel < maxnel) {
- mysids[mynel++] = sid;
- } else {
- maxnel += SIDS_NEL;
- mysids2 = kmalloc(maxnel*sizeof(*mysids2), GFP_ATOMIC);
- if (!mysids2) {
- rc = -ENOMEM;
- kfree(mysids);
- goto out_unlock;
- }
- memset(mysids2, 0, maxnel*sizeof(*mysids2));
- memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
- kfree(mysids);
- mysids = mysids2;
- mysids[mynel++] = sid;
- }
+ memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
+ kfree(mysids);
+ mysids = mysids2;
+ mysids[mynel++] = sid;
}
- mls_end_user_ranges;
}
}
goto out;
}
- *names = (char**)kmalloc(sizeof(char*) * *len, GFP_ATOMIC);
+ *names = kcalloc(*len, sizeof(char*), GFP_ATOMIC);
if (!*names)
goto err;
- memset(*names, 0, sizeof(char*) * *len);
- *values = (int*)kmalloc(sizeof(int) * *len, GFP_ATOMIC);
+ *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
if (!*values)
goto err;
size_t name_len;
(*values)[i] = policydb.bool_val_to_struct[i]->state;
name_len = strlen(policydb.p_bool_val_to_name[i]) + 1;
- (*names)[i] = (char*)kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
+ (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
if (!(*names)[i])
goto err;
strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len);
err:
if (*names) {
for (i = 0; i < *len; i++)
- if ((*names)[i])
- kfree((*names)[i]);
+ kfree((*names)[i]);
}
- if (*values)
- kfree(*values);
+ kfree(*values);
goto out;
}