forked from sektioneins/suhosin
/
ufilter.c
375 lines (318 loc) · 11.2 KB
/
ufilter.c
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/*
+----------------------------------------------------------------------+
| Suhosin Version 1 |
+----------------------------------------------------------------------+
| Copyright (c) 2006-2007 The Hardened-PHP Project |
| Copyright (c) 2007-2014 SektionEins GmbH |
+----------------------------------------------------------------------+
| This source file is subject to version 3.01 of the PHP license, |
| that is bundled with this package in the file LICENSE, and is |
| available through the world-wide-web at the following url: |
| http://www.php.net/license/3_01.txt |
| If you did not receive a copy of the PHP license and are unable to |
| obtain it through the world-wide-web, please send a note to |
| license@php.net so we can mail you a copy immediately. |
+----------------------------------------------------------------------+
| Author: Stefan Esser <sesser@sektioneins.de> |
+----------------------------------------------------------------------+
*/
/*
$Id: ufilter.c,v 1.1.1.1 2007-11-28 01:15:35 sesser Exp $
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "php.h"
#include "php_ini.h"
#include "ext/standard/info.h"
#include "php_suhosin.h"
#include "php_variables.h"
#include "suhosin_rfc1867.h"
PHP_SUHOSIN_API int (*old_rfc1867_callback)(unsigned int event, void *event_data, void **extra TSRMLS_DC) = NULL;
#if !HAVE_RFC1867_CALLBACK
PHP_SUHOSIN_API int (*php_rfc1867_callback)(unsigned int event, void *event_data, void **extra TSRMLS_DC) = NULL;
#endif
static int is_protected_varname(char *var, int var_len)
{
switch (var_len) {
case 18:
if (memcmp(var, "HTTP_RAW_POST_DATA", 18)==0) goto protected_varname2;
break;
case 17:
if (memcmp(var, "HTTP_SESSION_VARS", 17)==0) goto protected_varname2;
break;
case 16:
if (memcmp(var, "HTTP_SERVER_VARS", 16)==0) goto protected_varname2;
if (memcmp(var, "HTTP_COOKIE_VARS", 16)==0) goto protected_varname2;
break;
case 15:
if (memcmp(var, "HTTP_POST_FILES", 15)==0) goto protected_varname2;
break;
case 14:
if (memcmp(var, "HTTP_POST_VARS", 14)==0) goto protected_varname2;
break;
case 13:
if (memcmp(var, "HTTP_GET_VARS", 13)==0) goto protected_varname2;
if (memcmp(var, "HTTP_ENV_VARS", 13)==0) goto protected_varname2;
break;
case 8:
if (memcmp(var, "_SESSION", 8)==0) goto protected_varname2;
if (memcmp(var, "_REQUEST", 8)==0) goto protected_varname2;
break;
case 7:
if (memcmp(var, "GLOBALS", 7)==0) goto protected_varname2;
if (memcmp(var, "_COOKIE", 7)==0) goto protected_varname2;
if (memcmp(var, "_SERVER", 7)==0) goto protected_varname2;
break;
case 6:
if (memcmp(var, "_FILES", 6)==0) goto protected_varname2;
break;
case 5:
if (memcmp(var, "_POST", 5)==0) goto protected_varname2;
break;
case 4:
if (memcmp(var, "_ENV", 4)==0) goto protected_varname2;
if (memcmp(var, "_GET", 4)==0) goto protected_varname2;
break;
}
return 0;
protected_varname2:
return 1;
}
/* {{{ SAPI_UPLOAD_VARNAME_FILTER_FUNC
*/
static int check_fileupload_varname(char *varname)
{
char *index, *prev_index = NULL, *var;
unsigned int var_len, total_len, depth = 0;
TSRMLS_FETCH();
var = estrdup(varname);
/* Normalize the variable name */
normalize_varname(var);
/* Find length of variable name */
index = strchr(var, '[');
total_len = strlen(var);
var_len = index ? index-var : total_len;
/* Drop this variable if it exceeds the varname/total length limit */
if (SUHOSIN_G(max_varname_length) && SUHOSIN_G(max_varname_length) < var_len) {
suhosin_log(S_FILES, "configured request variable name length limit exceeded - dropped variable '%s'", var);
if (!SUHOSIN_G(simulation)) {
goto return_failure;
}
}
if (SUHOSIN_G(max_totalname_length) && SUHOSIN_G(max_totalname_length) < total_len) {
suhosin_log(S_FILES, "configured request variable total name length limit exceeded - dropped variable '%s'", var);
if (!SUHOSIN_G(simulation)) {
goto return_failure;
}
}
if (SUHOSIN_G(max_post_name_length) && SUHOSIN_G(max_post_name_length) < var_len) {
suhosin_log(S_FILES, "configured POST variable name length limit exceeded - dropped variable '%s'", var);
if (!SUHOSIN_G(simulation)) {
goto return_failure;
}
}
if (SUHOSIN_G(max_post_totalname_length) && SUHOSIN_G(max_post_totalname_length) < var_len) {
suhosin_log(S_FILES, "configured POST variable total name length limit exceeded - dropped variable '%s'", var);
if (!SUHOSIN_G(simulation)) {
goto return_failure;
}
}
/* Find out array depth */
while (index) {
char *index_end;
unsigned int index_length;
/* overjump '[' */
index++;
/* increase array depth */
depth++;
index_end = strchr(index, ']');
if (index_end == NULL) {
index_end = index+strlen(index);
}
index_length = index_end - index;
if (SUHOSIN_G(max_array_index_length) && SUHOSIN_G(max_array_index_length) < index_length) {
suhosin_log(S_FILES, "configured request variable array index length limit exceeded - dropped variable '%s'", var);
if (!SUHOSIN_G(simulation)) {
goto return_failure;
}
}
if (SUHOSIN_G(max_post_array_index_length) && SUHOSIN_G(max_post_array_index_length) < index_length) {
suhosin_log(S_FILES, "configured POST variable array index length limit exceeded - dropped variable '%s'", var);
if (!SUHOSIN_G(simulation)) {
goto return_failure;
}
}
index = strchr(index, '[');
}
/* Drop this variable if it exceeds the array depth limit */
if (SUHOSIN_G(max_array_depth) && SUHOSIN_G(max_array_depth) < depth) {
suhosin_log(S_FILES, "configured request variable array depth limit exceeded - dropped variable '%s'", var);
if (!SUHOSIN_G(simulation)) {
goto return_failure;
}
}
if (SUHOSIN_G(max_post_array_depth) && SUHOSIN_G(max_post_array_depth) < depth) {
suhosin_log(S_FILES, "configured POST variable array depth limit exceeded - dropped variable '%s'", var);
if (!SUHOSIN_G(simulation)) {
goto return_failure;
}
}
/* Drop this variable if it is one of GLOBALS, _GET, _POST, ... */
/* This is to protect several silly scripts that do globalizing themself */
if (is_protected_varname(var, var_len)) {
suhosin_log(S_FILES, "tried to register forbidden variable '%s' through FILE variables", var);
if (!SUHOSIN_G(simulation)) {
goto return_failure;
}
}
efree(var);
return SUCCESS;
return_failure:
efree(var);
return FAILURE;
}
/* }}} */
int suhosin_rfc1867_filter(unsigned int event, void *event_data, void **extra TSRMLS_DC)
{
int retval = SUCCESS;
SDEBUG("rfc1867_filter %u", event);
switch (event) {
case MULTIPART_EVENT_START:
case MULTIPART_EVENT_FORMDATA:
/* nothing todo */
break;
case MULTIPART_EVENT_FILE_START:
{
multipart_event_file_start *mefs = (multipart_event_file_start *) event_data;
/* Drop if no more variables flag is set */
if (SUHOSIN_G(no_more_uploads)) {
goto continue_with_failure;
}
/* Drop this fileupload if the limit is reached */
if (SUHOSIN_G(upload_limit) && SUHOSIN_G(upload_limit) <= SUHOSIN_G(num_uploads)) {
suhosin_log(S_FILES, "configured fileupload limit exceeded - file dropped");
if (!SUHOSIN_G(simulation)) {
SUHOSIN_G(no_more_uploads) = 1;
goto continue_with_failure;
}
}
if (check_fileupload_varname(mefs->name) == FAILURE) {
goto continue_with_failure;
}
}
break;
case MULTIPART_EVENT_FILE_DATA:
if (SUHOSIN_G(upload_disallow_elf)) {
multipart_event_file_data *mefd = (multipart_event_file_data *) event_data;
if (mefd->offset == 0 && mefd->length > 10) {
if (mefd->data[0] == 0x7F && mefd->data[1] == 'E' && mefd->data[2] == 'L' && mefd->data[3] == 'F') {
suhosin_log(S_FILES, "uploaded file is an ELF executable - file dropped");
if (!SUHOSIN_G(simulation)) {
goto continue_with_failure;
}
}
}
}
if (SUHOSIN_G(upload_disallow_binary)) {
multipart_event_file_data *mefd = (multipart_event_file_data *) event_data;
size_t i;
for (i=0; i<mefd->length; i++) {
if (mefd->data[i] < 32 && !isspace(mefd->data[i])) {
suhosin_log(S_FILES, "uploaded file contains binary data - file dropped");
if (!SUHOSIN_G(simulation)) {
goto continue_with_failure;
}
}
}
}
if (SUHOSIN_G(upload_remove_binary)) {
multipart_event_file_data *mefd = (multipart_event_file_data *) event_data;
size_t i, j;
for (i=0, j=0; i<mefd->length; i++) {
if (mefd->data[i] >= 32 || isspace(mefd->data[i])) {
mefd->data[j++] = mefd->data[i];
}
}
SDEBUG("removing binary %u %u",i,j);
/* IMPORTANT FOR DAISY CHAINING */
mefd->length = j;
if (mefd->newlength) {
*mefd->newlength = j;
}
}
break;
case MULTIPART_EVENT_FILE_END:
if (SUHOSIN_G(upload_verification_script)) {
multipart_event_file_end *mefe = (multipart_event_file_end *) event_data;
char cmd[8192];
FILE *in;
int first=1;
char *sname = SUHOSIN_G(upload_verification_script);
/* ignore files that will get deleted anyway */
if (mefe->cancel_upload) {
break;
}
/* ignore empty scriptnames */
while (isspace(*sname)) ++sname;
if (*sname == 0) {
SUHOSIN_G(num_uploads)++;
break;
}
ap_php_snprintf(cmd, sizeof(cmd), "%s %s", sname, mefe->temp_filename);
if ((in=VCWD_POPEN(cmd, "r"))==NULL) {
suhosin_log(S_FILES, "unable to execute fileupload verification script %s - file dropped", sname);
if (!SUHOSIN_G(simulation)) {
goto continue_with_failure;
} else {
goto continue_with_next;
}
}
retval = FAILURE;
/* read and forget the result */
while (1) {
int readbytes = fread(cmd, 1, sizeof(cmd), in);
if (readbytes<=0) {
break;
}
if (first) {
retval = atoi(cmd) == 1 ? SUCCESS : FAILURE;
first = 0;
}
}
pclose(in);
}
if (retval != SUCCESS) {
suhosin_log(S_FILES, "fileupload verification script disallows file - file dropped");
if (!SUHOSIN_G(simulation)) {
goto continue_with_failure;
}
}
SUHOSIN_G(num_uploads)++;
break;
case MULTIPART_EVENT_END:
/* nothing todo */
break;
default:
/* unknown: return failure */
goto continue_with_failure;
}
continue_with_next:
#if HAVE_RFC1867_CALLBACK
if (php_rfc1867_callback != NULL) {
return php_rfc1867_callback(event, event_data, extra TSRMLS_CC);
}
#endif
return SUCCESS;
continue_with_failure:
SUHOSIN_G(abort_request) = 1;
return FAILURE;
}
/*
* Local variables:
* tab-width: 4
* c-basic-offset: 4
* End:
* vim600: sw=4 ts=4 fdm=marker
* vim<600: sw=4 ts=4
*/