147 lines
4.2 KiB
C++

/*
* ModSecurity, http://www.modsecurity.org/
* Copyright (c) 2015 Trustwave Holdings, Inc. (http://www.trustwave.com/)
*
* You may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* If any of the files related to licensing are missing or if you have any
* other questions related to licensing please contact Trustwave Holdings, Inc.
* directly using the email address security@modsecurity.org.
*
*/
#include "src/request_body_processor/xml.h"
#include <list>
#include <iostream>
#include <string>
namespace modsecurity {
namespace RequestBodyProcessor {
#ifdef WITH_LIBXML2
XML::XML(Transaction *transaction)
: m_transaction(transaction) {
m_data.doc = NULL;
m_data.parsing_ctx = NULL;
m_data.sax_handler = NULL;
}
XML::~XML() {
if (m_data.parsing_ctx != NULL) {
xmlFreeParserCtxt(m_data.parsing_ctx);
m_data.parsing_ctx = NULL;
}
if (m_data.doc != NULL) {
xmlFreeDoc(m_data.doc);
m_data.doc = NULL;
}
}
bool XML::init() {
xmlParserInputBufferCreateFilenameFunc entity;
if (m_transaction->m_rules->m_secXMLExternalEntity
== RulesProperties::TrueConfigBoolean) {
entity = xmlParserInputBufferCreateFilenameDefault(
__xmlParserInputBufferCreateFilename);
} else {
entity = xmlParserInputBufferCreateFilenameDefault(
this->unloadExternalEntity);
}
return true;
}
xmlParserInputBufferPtr XML::unloadExternalEntity(const char *URI,
xmlCharEncoding enc) {
return NULL;
}
bool XML::processChunk(const char *buf, unsigned int size,
std::string *error) {
/* We want to initialise our parsing context here, to
* enable us to pass it the first chunk of data so that
* it can attempt to auto-detect the encoding.
*/
if (m_data.parsing_ctx == NULL) {
/* First invocation. */
ms_dbg_a(m_transaction, 4, "XML: Initialising parser.");
/* NOTE When Sax interface is used libxml will not
* create the document object, but we need it.
msr->xml->sax_handler = (xmlSAXHandler *)apr_pcalloc(msr->mp,
sizeof(xmlSAXHandler));
if (msr->xml->sax_handler == NULL) return -1;
msr->xml->sax_handler->error = xml_receive_sax_error;
msr->xml->sax_handler->warning = xml_receive_sax_error;
msr->xml->parsing_ctx = xmlCreatePushParserCtxt(msr->xml->sax_handler,
msr, buf, size, "body.xml");
*/
m_data.parsing_ctx = xmlCreatePushParserCtxt(NULL, NULL,
buf, size, "body.xml");
if (m_data.parsing_ctx == NULL) {
ms_dbg_a(m_transaction, 4,
"XML: Failed to create parsing context.");
error->assign("XML: Failed to create parsing context.");
return false;
}
return true;
}
/* Not a first invocation. */
xmlParseChunk(m_data.parsing_ctx, buf, size, 0);
if (m_data.parsing_ctx->wellFormed != 1) {
error->assign("XML: Failed to create parsing context.");
ms_dbg_a(m_transaction, 4, "XML: Failed parsing document.");
return false;
}
return true;
}
bool XML::complete(std::string *error) {
/* Only if we have a context, meaning we've done some work. */
if (m_data.parsing_ctx != NULL) {
/* This is how we signalise the end of parsing to libxml. */
xmlParseChunk(m_data.parsing_ctx, NULL, 0, 1);
/* Preserve the results for our reference. */
m_data.well_formed = m_data.parsing_ctx->wellFormed;
m_data.doc = m_data.parsing_ctx->myDoc;
/* Clean up everything else. */
xmlFreeParserCtxt(m_data.parsing_ctx);
m_data.parsing_ctx = NULL;
ms_dbg_a(m_transaction, 4, "XML: Parsing complete (well_formed " \
+ std::to_string(m_data.well_formed) + ").");
if (m_data.well_formed != 1) {
error->assign("XML: Failed parsing document.");
ms_dbg_a(m_transaction, 4, "XML: Failed parsing document.");
return false;
}
}
return true;
}
#endif
} // namespace RequestBodyProcessor
} // namespace modsecurity