*scontext = NULL;
*scontext_len = 0;
+ if (context->len) {
+ *scontext_len = context->len;
+ *scontext = kstrdup(context->str, GFP_ATOMIC);
+ if (!(*scontext))
+ return -ENOMEM;
+ return 0;
+ }
+
/* Compute the size of the context. */
*scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1;
*scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1;
return initial_sid_to_string[sid];
}
-/**
- * security_sid_to_context - Obtain a context for a given SID.
- * @sid: security identifier, SID
- * @scontext: security context
- * @scontext_len: length in bytes
- *
- * Write the string representation of the context associated with @sid
- * into a dynamically allocated string of the correct size. Set @scontext
- * to point to this string and set @scontext_len to the length of the string.
- */
-int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
+static int security_sid_to_context_core(u32 sid, char **scontext,
+ u32 *scontext_len, int force)
{
struct context *context;
int rc = 0;
goto out;
}
POLICY_RDLOCK;
- context = sidtab_search(&sidtab, sid);
+ if (force)
+ context = sidtab_search_force(&sidtab, sid);
+ else
+ context = sidtab_search(&sidtab, sid);
if (!context) {
printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
__func__, sid);
}
-static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
- u32 *sid, u32 def_sid, gfp_t gfp_flags)
+/**
+ * security_sid_to_context - Obtain a context for a given SID.
+ * @sid: security identifier, SID
+ * @scontext: security context
+ * @scontext_len: length in bytes
+ *
+ * Write the string representation of the context associated with @sid
+ * into a dynamically allocated string of the correct size. Set @scontext
+ * to point to this string and set @scontext_len to the length of the string.
+ */
+int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
{
- char *scontext2;
- struct context context;
+ return security_sid_to_context_core(sid, scontext, scontext_len, 0);
+}
+
+int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len)
+{
+ return security_sid_to_context_core(sid, scontext, scontext_len, 1);
+}
+
+static int string_to_context_struct(struct policydb *pol,
+ struct sidtab *sidtabp,
+ const char *scontext,
+ u32 scontext_len,
+ struct context *ctx,
+ u32 def_sid,
+ gfp_t gfp_flags)
+{
+ char *scontext2 = NULL;
struct role_datum *role;
struct type_datum *typdatum;
struct user_datum *usrdatum;
char *scontextp, *p, oldc;
int rc = 0;
- if (!ss_initialized) {
- int i;
+ context_init(ctx);
- for (i = 1; i < SECINITSID_NUM; i++) {
- if (!strcmp(initial_sid_to_string[i], scontext)) {
- *sid = i;
- goto out;
- }
- }
- *sid = SECINITSID_KERNEL;
- goto out;
- }
- *sid = SECSID_NULL;
-
- /* Copy the string so that we can modify the copy as we parse it.
- The string should already by null terminated, but we append a
- null suffix to the copy to avoid problems with the existing
- attr package, which doesn't view the null terminator as part
- of the attribute value. */
+ /* Copy the string so that we can modify the copy as we parse it. */
scontext2 = kmalloc(scontext_len+1, gfp_flags);
if (!scontext2) {
rc = -ENOMEM;
memcpy(scontext2, scontext, scontext_len);
scontext2[scontext_len] = 0;
- context_init(&context);
- *sid = SECSID_NULL;
-
- POLICY_RDLOCK;
-
/* Parse the security context. */
rc = -EINVAL;
p++;
if (*p == 0)
- goto out_unlock;
+ goto out;
*p++ = 0;
- usrdatum = hashtab_search(policydb.p_users.table, scontextp);
+ usrdatum = hashtab_search(pol->p_users.table, scontextp);
if (!usrdatum)
- goto out_unlock;
+ goto out;
- context.user = usrdatum->value;
+ ctx->user = usrdatum->value;
/* Extract role. */
scontextp = p;
p++;
if (*p == 0)
- goto out_unlock;
+ goto out;
*p++ = 0;
- role = hashtab_search(policydb.p_roles.table, scontextp);
+ role = hashtab_search(pol->p_roles.table, scontextp);
if (!role)
- goto out_unlock;
- context.role = role->value;
+ goto out;
+ ctx->role = role->value;
/* Extract type. */
scontextp = p;
oldc = *p;
*p++ = 0;
- typdatum = hashtab_search(policydb.p_types.table, scontextp);
+ typdatum = hashtab_search(pol->p_types.table, scontextp);
if (!typdatum)
- goto out_unlock;
+ goto out;
- context.type = typdatum->value;
+ ctx->type = typdatum->value;
- rc = mls_context_to_sid(oldc, &p, &context, &sidtab, def_sid);
+ rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid);
if (rc)
- goto out_unlock;
+ goto out;
if ((p - scontext2) < scontext_len) {
rc = -EINVAL;
- goto out_unlock;
+ goto out;
}
/* Check the validity of the new context. */
- if (!policydb_context_isvalid(&policydb, &context)) {
+ if (!policydb_context_isvalid(pol, ctx)) {
rc = -EINVAL;
- goto out_unlock;
+ context_destroy(ctx);
+ goto out;
}
- /* Obtain the new sid. */
- rc = sidtab_context_to_sid(&sidtab, &context, sid);
-out_unlock:
- POLICY_RDUNLOCK;
- context_destroy(&context);
+ rc = 0;
+out:
kfree(scontext2);
+ return rc;
+}
+
+static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
+ u32 *sid, u32 def_sid, gfp_t gfp_flags,
+ int force)
+{
+ struct context context;
+ int rc = 0;
+
+ if (!ss_initialized) {
+ int i;
+
+ for (i = 1; i < SECINITSID_NUM; i++) {
+ if (!strcmp(initial_sid_to_string[i], scontext)) {
+ *sid = i;
+ goto out;
+ }
+ }
+ *sid = SECINITSID_KERNEL;
+ goto out;
+ }
+ *sid = SECSID_NULL;
+
+ POLICY_RDLOCK;
+ rc = string_to_context_struct(&policydb, &sidtab,
+ scontext, scontext_len,
+ &context, def_sid, gfp_flags);
+ if (rc == -EINVAL && force) {
+ context.str = kmalloc(scontext_len+1, gfp_flags);
+ if (!context.str) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ memcpy(context.str, scontext, scontext_len);
+ context.str[scontext_len] = 0;
+ context.len = scontext_len;
+ } else if (rc)
+ goto out;
+ rc = sidtab_context_to_sid(&sidtab, &context, sid);
+ if (rc)
+ context_destroy(&context);
out:
+ POLICY_RDUNLOCK;
return rc;
}
int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid)
{
return security_context_to_sid_core(scontext, scontext_len,
- sid, SECSID_NULL, GFP_KERNEL);
+ sid, SECSID_NULL, GFP_KERNEL, 0);
}
/**
* 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).
+ * Implicitly forces adding of the context even if it cannot be mapped yet.
* Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
* memory is available, or 0 on success.
*/
u32 *sid, u32 def_sid, gfp_t gfp_flags)
{
return security_context_to_sid_core(scontext, scontext_len,
- sid, def_sid, gfp_flags);
+ sid, def_sid, gfp_flags, 1);
+}
+
+int security_context_to_sid_force(const char *scontext, u32 scontext_len,
+ u32 *sid)
+{
+ return security_context_to_sid_core(scontext, scontext_len,
+ sid, SECSID_NULL, GFP_KERNEL, 1);
}
static int compute_sid_handle_invalid_context(
char *s;
u32 len;
- context_struct_to_string(context, &s, &len);
- printk(KERN_ERR "SELinux: context %s is invalid\n", s);
- kfree(s);
+ if (!context_struct_to_string(context, &s, &len)) {
+ printk(KERN_WARNING
+ "SELinux: Context %s would be invalid if enforcing\n",
+ s);
+ kfree(s);
+ }
}
return rc;
}
args = p;
+ if (c->str) {
+ struct context ctx;
+ rc = string_to_context_struct(args->newp, NULL, c->str,
+ c->len, &ctx, SECSID_NULL,
+ GFP_KERNEL);
+ if (!rc) {
+ printk(KERN_INFO
+ "SELinux: Context %s became valid (mapped).\n",
+ c->str);
+ /* Replace string with mapped representation. */
+ kfree(c->str);
+ memcpy(c, &ctx, sizeof(*c));
+ goto out;
+ } else if (rc == -EINVAL) {
+ /* Retain string representation for later mapping. */
+ rc = 0;
+ goto out;
+ } else {
+ /* Other error condition, e.g. ENOMEM. */
+ printk(KERN_ERR
+ "SELinux: Unable to map context %s, rc = %d.\n",
+ c->str, -rc);
+ goto out;
+ }
+ }
+
rc = context_cpy(&oldc, c);
if (rc)
goto out;
}
context_destroy(&oldc);
+ rc = 0;
out:
return rc;
bad:
- context_struct_to_string(&oldc, &s, &len);
+ /* Map old representation to string and save it. */
+ if (context_struct_to_string(&oldc, &s, &len))
+ return -ENOMEM;
context_destroy(&oldc);
- printk(KERN_ERR "SELinux: invalidating context %s\n", s);
- kfree(s);
+ context_destroy(c);
+ c->str = s;
+ c->len = len;
+ printk(KERN_INFO
+ "SELinux: Context %s became invalid (unmapped).\n",
+ c->str);
+ rc = 0;
goto out;
}
return -EINVAL;
}
- sidtab_init(&newsidtab);
+ if (sidtab_init(&newsidtab)) {
+ LOAD_UNLOCK;
+ policydb_destroy(&newpolicydb);
+ return -ENOMEM;
+ }
/* Verify that the kernel defined classes are correct. */
if (validate_classes(&newpolicydb)) {
goto err;
}
- /* Convert the internal representations of contexts
- in the new SID table and remove invalid SIDs. */
+ /*
+ * Convert the internal representations of contexts
+ * in the new SID table.
+ */
args.oldp = &policydb;
args.newp = &newpolicydb;
- sidtab_map_remove_on_error(&newsidtab, convert_context, &args);
+ rc = sidtab_map(&newsidtab, convert_context, &args);
+ if (rc)
+ goto err;
/* Save the old policydb and SID table to free later. */
memcpy(&oldpolicydb, &policydb, sizeof policydb);
POLICY_RDLOCK;
+ context_init(&usercon);
+
fromcon = sidtab_search(&sidtab, fromsid);
if (!fromcon) {
rc = -EINVAL;
projects / linux-2.6 / commitdiff