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@chregu
Created October 3, 2011 16:28
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Index: ext/xsl/tests/bug54446.phpt
===================================================================
--- ext/xsl/tests/bug54446.phpt (revision 0)
+++ ext/xsl/tests/bug54446.phpt (revision 0)
@@ -0,0 +1,95 @@
+--TEST--
+Bug #54446 (Arbitrary file creation via libxslt 'output' extension)
+--SKIPIF--
+<?php
+if (!extension_loaded('xsl')) die("skip Extension XSL is required\n");
+?>
+--FILE--
+<?php
+include("prepare.inc");
+
+$outputfile = dirname(__FILE__)."/bug54446test.txt";
+if (file_exists($outputfile)) {
+ unlink($outputfile);
+}
+
+$sXsl = <<<EOT
+<xsl:stylesheet version="1.0"
+ xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+ xmlns:sax="http://icl.com/saxon"
+ extension-element-prefixes="sax">
+
+ <xsl:template match="/">
+ <sax:output href="$outputfile" method="text">
+ <xsl:value-of select="'0wn3d via PHP and libxslt ...'"/>
+ </sax:output>
+ </xsl:template>
+
+</xsl:stylesheet>
+EOT;
+
+$xsl->loadXML( $sXsl );
+
+# START XSLT
+$proc->importStylesheet( $xsl );
+
+# TRASNFORM & PRINT
+print $proc->transformToXML( $dom );
+
+
+if (file_exists($outputfile)) {
+ print "$outputfile exists, but shouldn't!\n";
+} else {
+ print "OK, no file created\n";
+}
+
+#SET NO SECURITY PREFS
+ini_set("xsl.security_prefs", XSL_SECPREF_NONE);
+
+# TRASNFORM & PRINT
+print $proc->transformToXML( $dom );
+
+
+if (file_exists($outputfile)) {
+ print "OK, file exists\n";
+} else {
+ print "$outputfile doesn't exist, but should!\n";
+}
+
+unlink($outputfile);
+
+#SET SECURITY PREFS AGAIN
+ini_set("xsl.security_prefs", XSL_SECPREF_WRITE_FILE | XSL_SECPREF_WRITE_NETWORK | XSL_SECPREF_CREATE_DIRECTORY);
+
+# TRASNFORM & PRINT
+print $proc->transformToXML( $dom );
+
+if (file_exists($outputfile)) {
+ print "$outputfile exists, but shouldn't!\n";
+} else {
+ print "OK, no file created\n";
+}
+
+
+--EXPECTF--
+Warning: XSLTProcessor::transformToXml(): runtime error: file %s line %s element output in %s on line %d
+
+Warning: XSLTProcessor::transformToXml(): File write for %s/bug54446test.txt refused in %s on line %s
+
+Warning: XSLTProcessor::transformToXml(): runtime error: file %s line %d element output in %s on line %d
+
+Warning: XSLTProcessor::transformToXml(): xsltDocumentElem: write rights for %s/bug54446test.txt denied in %s on line %d
+OK, no file created
+OK, file exists
+
+Warning: XSLTProcessor::transformToXml(): runtime error: file %s line %s element output in %s on line %d
+
+Warning: XSLTProcessor::transformToXml(): File write for %s/bug54446test.txt refused in %s on line %s
+
+Warning: XSLTProcessor::transformToXml(): runtime error: file %s line %d element output in %s on line %d
+
+Warning: XSLTProcessor::transformToXml(): xsltDocumentElem: write rights for %s/bug54446test.txt denied in %s on line %d
+OK, no file created
+--CREDITS--
+Christian Stocker, chregu@php.net
+
Index: ext/xsl/php_xsl.h
===================================================================
--- ext/xsl/php_xsl.h (revision 317654)
+++ ext/xsl/php_xsl.h (working copy)
@@ -32,6 +32,7 @@
#include <libxslt/xsltInternals.h>
#include <libxslt/xsltutils.h>
#include <libxslt/transform.h>
+#include <libxslt/security.h>
#if HAVE_XSL_EXSLT
#include <libexslt/exslt.h>
#include <libexslt/exsltconfig.h>
@@ -43,6 +44,13 @@
#include <libxslt/extensions.h>
#include <libxml/xpathInternals.h>
+#define XSL_SECPREF_NONE 0
+#define XSL_SECPREF_READ_FILE 2
+#define XSL_SECPREF_WRITE_FILE 4
+#define XSL_SECPREF_CREATE_DIRECTORY 8
+#define XSL_SECPREF_READ_NETWORK 16
+#define XSL_SECPREF_WRITE_NETWORK 32
+
typedef struct _xsl_object {
zend_object std;
void *ptr;
Index: ext/xsl/xsltprocessor.c
===================================================================
--- ext/xsl/xsltprocessor.c (revision 317654)
+++ ext/xsl/xsltprocessor.c (working copy)
@@ -475,6 +475,9 @@
zval *doXInclude, *member;
zend_object_handlers *std_hnd;
FILE *f;
+ int secPrefsError;
+ int secPrefsIni;
+ xsltSecurityPrefsPtr secPrefs = NULL;
node = php_libxml_import_node(docp TSRMLS_CC);
@@ -531,11 +534,56 @@
}
efree(member);
- newdocp = xsltApplyStylesheetUser(style, doc, (const char**) params, NULL, f, ctxt);
+
+ secPrefsIni = INI_INT("xsl.security_prefs");
+
+ //if securityPrefs is set to NONE, we don't have to do any checks, but otherwise...
+ if (secPrefsIni != XSL_SECPREF_NONE) {
+ secPrefs = xsltNewSecurityPrefs();
+ if (secPrefsIni & XSL_SECPREF_READ_FILE ) {
+ if (0 != xsltSetSecurityPrefs(secPrefs, XSLT_SECPREF_READ_FILE, xsltSecurityForbid)) {
+ secPrefsError = 1;
+ }
+ }
+ if (secPrefsIni & XSL_SECPREF_WRITE_FILE ) {
+ if (0 != xsltSetSecurityPrefs(secPrefs, XSLT_SECPREF_WRITE_FILE, xsltSecurityForbid)) {
+ secPrefsError = 1;
+ }
+ }
+ if (secPrefsIni & XSL_SECPREF_CREATE_DIRECTORY ) {
+ if (0 != xsltSetSecurityPrefs(secPrefs, XSLT_SECPREF_CREATE_DIRECTORY, xsltSecurityForbid)) {
+ secPrefsError = 1;
+ }
+ }
+ if (secPrefsIni & XSL_SECPREF_READ_NETWORK) {
+ if (0 != xsltSetSecurityPrefs(secPrefs, XSLT_SECPREF_READ_NETWORK, xsltSecurityForbid)) {
+ secPrefsError = 1;
+ }
+ }
+ if (secPrefsIni & XSL_SECPREF_WRITE_NETWORK) {
+ if (0 != xsltSetSecurityPrefs(secPrefs, XSLT_SECPREF_WRITE_NETWORK, xsltSecurityForbid)) {
+ secPrefsError = 1;
+ }
+ }
+
+ if (0 != xsltSetCtxtSecurityPrefs(secPrefs, ctxt)) {
+ secPrefsError = 1;
+ }
+ }
+
+ if (secPrefsError == 1) {
+ php_error_docref(NULL TSRMLS_CC, E_WARNING, "Can't set libxslt security properties, not doing transformation for security reasons");
+ } else {
+ newdocp = xsltApplyStylesheetUser(style, doc, (const char**) params, NULL, f, ctxt);
+ }
if (f) {
fclose(f);
}
+
xsltFreeTransformContext(ctxt);
+ if (secPrefs) {
+ xsltFreeSecurityPrefs(secPrefs);
+ }
if (intern->node_list != NULL) {
zend_hash_destroy(intern->node_list);
Index: ext/xsl/php_xsl.c
===================================================================
--- ext/xsl/php_xsl.c (revision 317654)
+++ ext/xsl/php_xsl.c (working copy)
@@ -141,6 +141,11 @@
}
/* }}} */
+PHP_INI_BEGIN()
+//XSL_SECPREF_CREATE_DIRECTORY | XSL_SECPREF_WRITE_NETWORK | XSL_SECPREF_WRITE_FILE == 44
+PHP_INI_ENTRY("xsl.security_prefs", "44", PHP_INI_ALL, NULL)
+PHP_INI_END()
+
/* {{{ PHP_MINIT_FUNCTION
*/
PHP_MINIT_FUNCTION(xsl)
@@ -167,6 +172,13 @@
REGISTER_LONG_CONSTANT("XSL_CLONE_NEVER", -1, CONST_CS | CONST_PERSISTENT);
REGISTER_LONG_CONSTANT("XSL_CLONE_ALWAYS", 1, CONST_CS | CONST_PERSISTENT);
+ REGISTER_LONG_CONSTANT("XSL_SECPREF_NONE", XSL_SECPREF_NONE, CONST_CS | CONST_PERSISTENT);
+ REGISTER_LONG_CONSTANT("XSL_SECPREF_READ_FILE", XSL_SECPREF_READ_FILE, CONST_CS | CONST_PERSISTENT);
+ REGISTER_LONG_CONSTANT("XSL_SECPREF_WRITE_FILE", XSL_SECPREF_WRITE_FILE, CONST_CS | CONST_PERSISTENT);
+ REGISTER_LONG_CONSTANT("XSL_SECPREF_CREATE_DIRECTORY", XSL_SECPREF_CREATE_DIRECTORY, CONST_CS | CONST_PERSISTENT);
+ REGISTER_LONG_CONSTANT("XSL_SECPREF_READ_NETWORK", XSL_SECPREF_READ_NETWORK, CONST_CS | CONST_PERSISTENT);
+ REGISTER_LONG_CONSTANT("XSL_SECPREF_WRITE_NETWORK", XSL_SECPREF_WRITE_NETWORK, CONST_CS | CONST_PERSISTENT);
+
REGISTER_LONG_CONSTANT("LIBXSLT_VERSION", LIBXSLT_VERSION, CONST_CS | CONST_PERSISTENT);
REGISTER_STRING_CONSTANT("LIBXSLT_DOTTED_VERSION", LIBXSLT_DOTTED_VERSION, CONST_CS | CONST_PERSISTENT);
@@ -175,6 +187,8 @@
REGISTER_STRING_CONSTANT("LIBEXSLT_DOTTED_VERSION", LIBEXSLT_DOTTED_VERSION, CONST_CS | CONST_PERSISTENT);
#endif
+ REGISTER_INI_ENTRIES();
+
return SUCCESS;
}
/* }}} */
@@ -258,6 +272,8 @@
xsltCleanupGlobals();
+ UNREGISTER_INI_ENTRIES();
+
return SUCCESS;
}
/* }}} */
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