/*
* Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
#include <assert.h>
#include <limits.h>
#include <setjmp.h>
#include <stdlib.h>
#include <string.h>
#include "jni.h"
#include "jvm.h"
#include "check_classname.h"
typedef unsigned short unicode;
static char *
skip_over_fieldname(
char *name, jboolean slash_okay,
unsigned int len);
static char *
skip_over_field_signature(
char *name, jboolean void_okay,
unsigned int len);
/*
* Return non-zero if the character is a valid in JVM class name, zero
* otherwise. The only characters currently disallowed from JVM class
* names are given in the table below:
*
* Character Hex Decimal
* '.' 0x2e 46
* '/' 0x2f 47
* ';' 0x3b 59
* '[' 0x5b 91
*
* (Method names have further restrictions dealing with the '<' and
* '>' characters.)
*/
static int isJvmIdentifier(unicode ch) {
if( ch >
91 || ch <
46 )
return 1;
/* Lowercase ASCII letters are > 91 */
else {
/* 46 <= ch <= 91 */
if (ch <=
90 && ch >=
60) {
return 1;
/* Uppercase ASCII recognized here */
}
else {
/* ch == 91 || 46 <= ch <= 59 */
if (ch ==
91 || ch ==
59 || ch <=
47)
return 0;
else
return 1;
}
}
}
static unicode
next_utf2unicode(
char **utfstring_ptr,
int * valid)
{
unsigned char *ptr = (
unsigned char *)(*utfstring_ptr);
unsigned char ch, ch2, ch3;
int length =
1;
/* default length */
unicode result =
0x80;
/* default bad result; */
*valid =
1;
switch ((ch = ptr[
0]) >>
4) {
default:
result = ch;
break;
case 0x8:
case 0x9:
case 0xA:
case 0xB:
case 0xF:
/* Shouldn't happen. */
*valid =
0;
break;
case 0xC:
case 0xD:
/* 110xxxxx 10xxxxxx */
if (((ch2 = ptr[
1]) &
0xC0) ==
0x80) {
unsigned char high_five = ch &
0x1F;
unsigned char low_six = ch2 &
0x3F;
result = (high_five <<
6) + low_six;
length =
2;
}
break;
case 0xE:
/* 1110xxxx 10xxxxxx 10xxxxxx */
if (((ch2 = ptr[
1]) &
0xC0) ==
0x80) {
if (((ch3 = ptr[
2]) &
0xC0) ==
0x80) {
unsigned char high_four = ch &
0x0f;
unsigned char mid_six = ch2 &
0x3f;
unsigned char low_six = ch3 &
0x3f;
result = (((high_four <<
6) + mid_six) <<
6) + low_six;
length =
3;
}
else {
length =
2;
}
}
break;
}
/* end of switch */
*utfstring_ptr = (
char *)(ptr + length);
return result;
}
/* Take pointer to a string. Skip over the longest part of the string that
* could be taken as a fieldname. Allow '/' if slash_okay is JNI_TRUE.
*
* Return a pointer to just past the fieldname. Return NULL if no fieldname
* at all was found, or in the case of slash_okay being true, we saw
* consecutive slashes (meaning we were looking for a qualified path but
* found something that was badly-formed).
*/
static char *
skip_over_fieldname(
char *name, jboolean slash_okay,
unsigned int length)
{
char *p;
unicode ch;
unicode last_ch =
0;
int valid =
1;
/* last_ch == 0 implies we are looking at the first char. */
for (p = name; p != name + length; last_ch = ch) {
char *old_p = p;
ch = *p;
if (ch <
128) {
p++;
if (isJvmIdentifier(ch)) {
continue;
}
}
else {
char *tmp_p = p;
ch = next_utf2unicode(&tmp_p, &valid);
if (valid ==
0)
return 0;
p = tmp_p;
if (isJvmIdentifier(ch)) {
continue;
}
}
if (slash_okay && ch ==
'/' && last_ch) {
if (last_ch ==
'/') {
return 0;
/* Don't permit consecutive slashes */
}
}
else if (ch ==
'_' || ch ==
'$') {
}
else {
return last_ch ? old_p :
0;
}
}
return last_ch ? p :
0;
}
/* Take pointer to a string. Skip over the longest part of the string that
* could be taken as a field signature. Allow "void" if void_okay.
*
* Return a pointer to just past the signature. Return NULL if no legal
* signature is found.
*/
static char *
skip_over_field_signature(
char *name, jboolean void_okay,
unsigned int length)
{
unsigned int array_dim =
0;
for (;length >
0;) {
switch (name[
0]) {
case JVM_SIGNATURE_VOID:
if (!void_okay)
return 0;
/* FALL THROUGH */
case JVM_SIGNATURE_BOOLEAN:
case JVM_SIGNATURE_BYTE:
case JVM_SIGNATURE_CHAR:
case JVM_SIGNATURE_SHORT:
case JVM_SIGNATURE_INT:
case JVM_SIGNATURE_FLOAT:
case JVM_SIGNATURE_LONG:
case JVM_SIGNATURE_DOUBLE:
return name +
1;
case JVM_SIGNATURE_CLASS: {
/* Skip over the classname, if one is there. */
char *p =
skip_over_fieldname(name +
1, JNI_TRUE, --length);
/* The next character better be a semicolon. */
if (p && p - name -
1 >
0 && p[
0] ==
';')
return p +
1;
return 0;
}
case JVM_SIGNATURE_ARRAY:
array_dim++;
/* JVMS 2nd ed. 4.10 */
/* The number of dimensions in an array is limited to 255 ... */
if (array_dim >
255) {
return 0;
}
/* The rest of what's there better be a legal signature. */
name++;
length--;
void_okay = JNI_FALSE;
break;
default:
return 0;
}
}
return 0;
}
/* Determine if the specified name is legal
* UTF name for a classname.
*
* Note that this routine expects the internal form of qualified classes:
* the dots should have been replaced by slashes.
*/
jboolean verifyClassname(
char *name, jboolean allowArrayClass)
{
size_t s = strlen(name);
assert(s <= UINT_MAX);
unsigned int length = (
unsigned int)s;
char *p;
if (length >
0 && name[
0] == JVM_SIGNATURE_ARRAY) {
if (!allowArrayClass) {
return JNI_FALSE;
}
else {
/* Everything that's left better be a field signature */
p = skip_over_field_signature(name, JNI_FALSE, length);
}
}
else {
/* skip over the fieldname. Slashes are okay */
p = skip_over_fieldname(name, JNI_TRUE, length);
}
return (p !=
0 && p - name == (ptrdiff_t)length);
}
/*
* Translates '.' to '/'. Returns JNI_TRUE if any / were present.
*/
jboolean verifyFixClassname(
char *name)
{
char *p = name;
jboolean slashesFound = JNI_FALSE;
int valid =
1;
while (valid !=
0 && *p !=
'\0') {
if (*p ==
'/') {
slashesFound = JNI_TRUE;
p++;
}
else if (*p ==
'.') {
*p++ =
'/';
}
else {
next_utf2unicode(&p, &valid);
}
}
return slashesFound && valid !=
0;
}
/*
* Translates '.' to '/'.
*/
void fixClassname(
char *name)
{
char *p = name;
int valid =
1;
while (valid !=
0 && *p !=
'\0') {
if (*p ==
'.') {
*p++ =
'/';
}
else {
next_utf2unicode(&p, &valid);
}
}
}
