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/* Copyright (C) 2005 Tresys Technology, LLC
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
/*
* Author: jmowery@tresys.com
*
*/
#include "sechecker.h"
#include "sechk_parse.h"
#include <apol/util.h>
#include <libxml/xmlreader.h>
#include <errno.h>
#include <string.h>
/* xml parser keywords */
#define SECHK_PARSE_SECHECKER_TAG "sechecker"
#define SECHK_PARSE_PROFILE_TAG "profile"
#define SECHK_PARSE_MODULE_TAG "module"
#define SECHK_PARSE_OPTION_TAG "option"
#define SECHK_PARSE_ITEM_TAG "item"
#define SECHK_PARSE_OUTPUT_TAG "output"
#define SECHK_PARSE_VALUE_ATTRIB "value"
#define SECHK_PARSE_NAME_ATTRIB "name"
#define SECHK_PARSE_VERSION_ATTRIB "version"
#define SECHK_PARSE_OUTPUT_NONE "none"
#define SECHK_PARSE_OUTPUT_QUIET "quiet"
#define SECHK_PARSE_OUTPUT_SHORT "short"
#define SECHK_PARSE_OUTPUT_VERBOSE "verbose"
static char *build_dtd_path(void)
{
char *path = NULL;
size_t path_sz = 0;
#ifdef PROFILE_INSTALL_DIR
if (apol_str_append(&path, &path_sz, "file://localhost/") == -1)
return NULL;
if (apol_str_append(&path, &path_sz, PROFILE_INSTALL_DIR) == -1)
return NULL;
if (apol_str_append(&path, &path_sz, "/sechecker.dtd") == -1)
return NULL;
return path;
#endif
return NULL;
}
/* Parsing functions */
/* Parse the configuration file. */
int sechk_lib_parse_xml_file(const char *filename, sechk_lib_t * lib)
{
xmlTextReaderPtr reader = NULL;
xmlDtdPtr dtd = NULL;
xmlDocPtr xml = NULL;
xmlValidCtxtPtr ctxt = NULL;
int tmp, ret = 0;
char *dtd_path = NULL;
/* this initializes the XML library and checks potential ABI mismatches
* between the version it was compiled for and the actual shared
* library used. */
LIBXML_TEST_VERSION;
reader = xmlReaderForFile(filename, NULL, 0);
if (!reader) {
ret = errno;
if (ret != ENOENT)
fprintf(stderr, "Error: Could not create xmlReader.\n");
goto exit_err;
}
dtd_path = build_dtd_path();
if (!dtd_path) {
fprintf(stderr, "Error: getting DTD path\n");
goto exit_err;
}
dtd = xmlParseDTD(NULL, (const xmlChar *)dtd_path);
free(dtd_path);
if (!dtd) {
fprintf(stderr, "Error: parsing DTD\n");
goto exit_err;
}
xml = xmlParseFile(filename);
if (!xml) {
fprintf(stderr, "Error: parsing sechecker profile\n");
goto exit_err;
}
ctxt = xmlNewValidCtxt();
if (!ctxt) {
fprintf(stderr, "Error: out of memory\n");
goto exit_err;
}
/* validate profile against the DTD */
if (xmlValidateDtd(ctxt, xml, dtd) == 0) {
fprintf(stderr, "Error: SEChecker profile contains invalid XML. Aborting.\n");
goto exit_err;
}
xmlFreeValidCtxt(ctxt);
xmlFreeDoc(xml);
xmlFreeDtd(dtd);
while (1) {
ret = xmlTextReaderRead(reader);
if (ret == -1) {
ret = errno;
fprintf(stderr, "Error: Error reading xml.\n");
goto exit_err;
}
if (ret == 0) /* no more nodes to read */
break;
tmp = sechk_lib_process_xml_node(reader, lib);
if (tmp == -1)
goto exit_err;
if (tmp == 1) {
ret = xmlTextReaderNext(reader);
if (ret == 0)
break;
if (ret == -1) {
ret = errno;
fprintf(stderr, "Error in xmlTextReaderNext()\n");
goto exit_err;
}
}
}
/* cleanup function for the XML library */
xmlCleanupParser();
xmlFreeTextReader(reader);
return 0;
exit_err:
xmlCleanupParser();
if (reader)
xmlFreeTextReader(reader);
if (ret)
errno = ret;
return -1;
}
/* process a single node in the xml file */
int sechk_lib_process_xml_node(xmlTextReaderPtr reader, sechk_lib_t * lib)
{
xmlChar *attrib = NULL;
int idx;
sechk_name_value_t *nv = NULL;
static xmlChar *option = NULL;
static xmlChar *value = NULL;
static sechk_module_t *current_module = NULL;
switch (xmlTextReaderNodeType(reader)) {
case XML_ELEMENT_DECL: /* closing tags */
if (xmlStrEqual(xmlTextReaderConstName(reader), (xmlChar *) SECHK_PARSE_MODULE_TAG) == 1) {
current_module = NULL;
} else if (xmlStrEqual(xmlTextReaderConstName(reader), (xmlChar *) SECHK_PARSE_OPTION_TAG) == 1) {
free(option);
option = NULL;
}
break;
case XML_ELEMENT_NODE: /* opening tags */
if (xmlStrEqual(xmlTextReaderConstName(reader), (xmlChar *) SECHK_PARSE_SECHECKER_TAG) == 1) {
/* parsing the <sechecker> tag */
attrib = xmlTextReaderGetAttribute(reader, (xmlChar *) SECHK_PARSE_VERSION_ATTRIB);
if (attrib) {
#ifdef SECHECKER_VERSION
if (atof((const char *)attrib) > atof(SECHECKER_VERSION)) {
fprintf(stderr,
"Error: sechecker version in profile is incorrect: expected %1.1f got %1.1f\n",
atof(SECHECKER_VERSION), atof((const char *)attrib));
goto exit_err;
}
#endif
free(attrib);
attrib = NULL;
} else {
fprintf(stderr, "Warning: sechecker version is not specified.\n");
}
} else if (xmlStrEqual(xmlTextReaderConstName(reader), (xmlChar *) SECHK_PARSE_MODULE_TAG) == 1) {
/* parsing the <module> tag */
attrib = xmlTextReaderGetAttribute(reader, (xmlChar *) SECHK_PARSE_NAME_ATTRIB);
if (attrib) {
if ((idx = sechk_lib_get_module_idx((const char *)attrib, lib)) == -1) {
fprintf(stderr, "Warning: module %s not found.\n", (const char *)attrib);
return 1; /* not a fatal error */
} else {
/* set the values on the existing module */
current_module = apol_vector_get_element(lib->modules, idx);
current_module->selected = true;
}
free(attrib);
attrib = NULL;
} else {
fprintf(stderr, "Error: module name is not specified.\n");
goto exit_err;
}
} else if (xmlStrEqual(xmlTextReaderConstName(reader), (xmlChar *) SECHK_PARSE_OPTION_TAG) == 1) {
/* parsing the <option> tag */
if (!current_module) {
fprintf(stderr, "Error: 'option' specified outside the scope of a module.\n");
goto exit_err;
}
/* read the name of the option */
option = xmlTextReaderGetAttribute(reader, (xmlChar *) SECHK_PARSE_NAME_ATTRIB);
if (!option) {
fprintf(stderr, "Error: option name is not specified.\n");
goto exit_err;
}
/* clear the options with this name that were set by defualt for this module */
sechk_lib_module_clear_option(current_module, (char *)option);
} else if (xmlStrEqual(xmlTextReaderConstName(reader), (xmlChar *) SECHK_PARSE_ITEM_TAG) == 1) {
/* parsing the <item> tag */
assert(current_module);
nv = sechk_name_value_new((char *)option, NULL);
/* read the value for this name value pair */
value = xmlTextReaderGetAttribute(reader, (xmlChar *) SECHK_PARSE_VALUE_ATTRIB);
if (!value) {
fprintf(stderr, "Error: item value is not specified.\n");
goto exit_err;
}
nv->value = strdup((char *)value);
free(value);
value = NULL;
/* add the nv pair to the module options */
apol_vector_append(current_module->options, (void *)nv);
nv = NULL;
} else if (xmlStrEqual(xmlTextReaderConstName(reader), (xmlChar *) SECHK_PARSE_OUTPUT_TAG) == 1) {
if (!current_module) {
fprintf(stderr, "Error: 'output' specified outside the scope of a module.\n");
goto exit_err;
}
attrib = xmlTextReaderGetAttribute(reader, (xmlChar *) SECHK_PARSE_VALUE_ATTRIB);
if (attrib) {
if (xmlStrEqual(attrib, (xmlChar *) SECHK_PARSE_OUTPUT_QUIET) == 1) {
current_module->outputformat = SECHK_OUT_QUIET;
} else if (xmlStrEqual(attrib, (xmlChar *) SECHK_PARSE_OUTPUT_VERBOSE) == 1) {
current_module->outputformat = SECHK_OUT_VERBOSE;
} else if (xmlStrEqual(attrib, (xmlChar *) SECHK_PARSE_OUTPUT_SHORT) == 1) {
current_module->outputformat = SECHK_OUT_SHORT;
} else if (xmlStrEqual(attrib, (xmlChar *) SECHK_PARSE_OUTPUT_NONE) == 1) {
current_module->outputformat = SECHK_OUT_NONE;
} else {
fprintf(stderr, "Error: invalid output value %s.\n", attrib);
goto exit_err;
}
free(attrib);
attrib = NULL;
} else {
fprintf(stderr, "Error: output value is not specified.\n");
goto exit_err;
}
}
break;
}
return 0;
exit_err:
sechk_name_value_free(nv);
errno = EIO;
return -1;
}
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