mirror of
https://github.com/owasp-modsecurity/ModSecurity.git
synced 2025-08-13 13:26:01 +03:00
147 lines
4.3 KiB
C
147 lines
4.3 KiB
C
/*
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* ModSecurity for Apache 2.x, http://www.modsecurity.org/
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* Copyright (c) 2004-2013 Trustwave Holdings, Inc. (http://www.trustwave.com/)
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*
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* You may not use this file except in compliance with
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* the License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* If any of the files related to licensing are missing or if you have any
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* other questions related to licensing please contact Trustwave Holdings, Inc.
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* directly using the email address security@modsecurity.org.
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*/
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#include "msc_xml.h"
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static xmlParserInputBufferPtr
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xml_unload_external_entity(const char *URI, xmlCharEncoding enc) {
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return NULL;
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}
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/**
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* Initialise XML parser.
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*/
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int xml_init(modsec_rec *msr, char **error_msg) {
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xmlParserInputBufferCreateFilenameFunc entity;
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if (error_msg == NULL) return -1;
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*error_msg = NULL;
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msr->xml = apr_pcalloc(msr->mp, sizeof(xml_data));
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if (msr->xml == NULL) return -1;
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if(msr->txcfg->xml_external_entity == 0) {
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entity = xmlParserInputBufferCreateFilenameDefault(xml_unload_external_entity);
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}
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return 1;
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}
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#if 0
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static void xml_receive_sax_error(void *data, const char *msg, ...) {
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modsec_rec *msr = (modsec_rec *)data;
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char message[256];
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if (msr == NULL) return;
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apr_snprintf(message, sizeof(message), "%s (line %d offset %d)",
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log_escape_nq(msr->mp, msr->xml->parsing_ctx->lastError.message),
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msr->xml->parsing_ctx->lastError.line,
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msr->xml->parsing_ctx->lastError.int2);
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msr_log(msr, 5, "XML: Parsing error: %s", message);
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}
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#endif
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/**
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* Feed one chunk of data to the XML parser.
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*/
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int xml_process_chunk(modsec_rec *msr, const char *buf, unsigned int size, char **error_msg) {
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if (error_msg == NULL) return -1;
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*error_msg = NULL;
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/* We want to initialise our parsing context here, to
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* enable us to pass it the first chunk of data so that
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* it can attempt to auto-detect the encoding.
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*/
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if (msr->xml->parsing_ctx == NULL) {
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/* First invocation. */
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msr_log(msr, 4, "XML: Initialising parser.");
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/* NOTE When Sax interface is used libxml will not
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* create the document object, but we need it.
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msr->xml->sax_handler = (xmlSAXHandler *)apr_pcalloc(msr->mp, sizeof(xmlSAXHandler));
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if (msr->xml->sax_handler == NULL) return -1;
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msr->xml->sax_handler->error = xml_receive_sax_error;
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msr->xml->sax_handler->warning = xml_receive_sax_error;
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msr->xml->parsing_ctx = xmlCreatePushParserCtxt(msr->xml->sax_handler, msr,
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buf, size, "body.xml");
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*/
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msr->xml->parsing_ctx = xmlCreatePushParserCtxt(NULL, NULL, buf, size, "body.xml");
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if (msr->xml->parsing_ctx == NULL) {
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*error_msg = apr_psprintf(msr->mp, "XML: Failed to create parsing context.");
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return -1;
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}
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} else {
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/* Not a first invocation. */
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xmlParseChunk(msr->xml->parsing_ctx, buf, size, 0);
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if (msr->xml->parsing_ctx->wellFormed != 1) {
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*error_msg = apr_psprintf(msr->mp, "XML: Failed parsing document.");
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return -1;
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}
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}
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return 1;
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}
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/**
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* Finalise XML parsing.
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*/
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int xml_complete(modsec_rec *msr, char **error_msg) {
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if (error_msg == NULL) return -1;
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*error_msg = NULL;
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/* Only if we have a context, meaning we've done some work. */
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if (msr->xml->parsing_ctx != NULL) {
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/* This is how we signalise the end of parsing to libxml. */
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xmlParseChunk(msr->xml->parsing_ctx, NULL, 0, 1);
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/* Preserve the results for our reference. */
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msr->xml->well_formed = msr->xml->parsing_ctx->wellFormed;
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msr->xml->doc = msr->xml->parsing_ctx->myDoc;
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/* Clean up everything else. */
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xmlFreeParserCtxt(msr->xml->parsing_ctx);
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msr->xml->parsing_ctx = NULL;
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msr_log(msr, 4, "XML: Parsing complete (well_formed %u).", msr->xml->well_formed);
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if (msr->xml->well_formed != 1) {
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*error_msg = apr_psprintf(msr->mp, "XML: Failed parsing document.");
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return -1;
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}
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}
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return 1;
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}
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/**
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* Frees the resources used for XML parsing.
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*/
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apr_status_t xml_cleanup(modsec_rec *msr) {
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if (msr->xml->doc != NULL) {
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xmlFreeDoc(msr->xml->doc);
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msr->xml->doc = NULL;
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}
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return 1;
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}
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