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/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); 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
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifdef CROSS_COMPILE
#include <ctype.h>
#define apr_isalnum(c) (isalnum(((unsigned char)(c))))
#define apr_isalpha(c) (isalpha(((unsigned char)(c))))
#define apr_iscntrl(c) (iscntrl(((unsigned char)(c))))
#define apr_isprint(c) (isprint(((unsigned char)(c))))
#define APR_HAVE_STDIO_H 1
#define APR_HAVE_STRING_H 1
#else
#include "apr.h"
#include "apr_lib.h"
#endif
#if defined(WIN32) || defined(OS2)
#define NEED_ENHANCED_ESCAPES
#endif
#if APR_HAVE_STDIO_H
#include <stdio.h>
#endif
#if APR_HAVE_STRING_H
#include <string.h>
#endif
/* A bunch of functions in util.c scan strings looking for certain characters.
* To make that more efficient we encode a lookup table.
*/
#define T_ESCAPE_SHELL_CMD (0x01)
#define T_ESCAPE_PATH_SEGMENT (0x02)
#define T_OS_ESCAPE_PATH (0x04)
#define T_HTTP_TOKEN_STOP (0x08)
#define T_ESCAPE_LOGITEM (0x10)
#define T_ESCAPE_FORENSIC (0x20)
#define T_ESCAPE_URLENCODED (0x40)
#define T_HTTP_CTRLS (0x80)
#define T_VCHAR_OBSTEXT (0x100)
#define T_URI_UNRESERVED (0x200)
int main(int argc, char *argv[])
{
unsigned c;
unsigned short flags;
printf("/* this file is automatically generated by gen_test_char, "
"do not edit */\n"
"#define T_ESCAPE_SHELL_CMD (%u)\n"
"#define T_ESCAPE_PATH_SEGMENT (%u)\n"
"#define T_OS_ESCAPE_PATH (%u)\n"
"#define T_HTTP_TOKEN_STOP (%u)\n"
"#define T_ESCAPE_LOGITEM (%u)\n"
"#define T_ESCAPE_FORENSIC (%u)\n"
"#define T_ESCAPE_URLENCODED (%u)\n"
"#define T_HTTP_CTRLS (%u)\n"
"#define T_VCHAR_OBSTEXT (%u)\n"
"#define T_URI_UNRESERVED (%u)\n"
"\n"
"static const unsigned short test_char_table[256] = {",
T_ESCAPE_SHELL_CMD,
T_ESCAPE_PATH_SEGMENT,
T_OS_ESCAPE_PATH,
T_HTTP_TOKEN_STOP,
T_ESCAPE_LOGITEM,
T_ESCAPE_FORENSIC,
T_ESCAPE_URLENCODED,
T_HTTP_CTRLS,
T_VCHAR_OBSTEXT,
T_URI_UNRESERVED
);
for (c = 0; c < 256; ++c) {
flags = 0;
if (c % 8 == 0)
printf("\n ");
/* escape_shell_cmd */
#ifdef NEED_ENHANCED_ESCAPES
/* Win32/OS2 have many of the same vulnerable characters
* as Unix sh, plus the carriage return and percent char.
* The proper escaping of these characters varies from unix
* since Win32/OS2 use carets or doubled-double quotes,
* and neither lf nor cr can be escaped. We escape unix
* specific as well, to assure that cross-compiled unix
* applications behave similarly when invoked on win32/os2.
*
* Rem please keep in-sync with apr's list in win32/filesys.c
*/
if (c && strchr("&;`'\"|*?~<>^()[]{}$\\\n\r%", c)) {
flags |= T_ESCAPE_SHELL_CMD;
}
#else
if (c && strchr("&;`'\"|*?~<>^()[]{}$\\\n", c)) {
flags |= T_ESCAPE_SHELL_CMD;
}
#endif
if (!apr_isalnum(c) && !strchr("$-_.+!*'(),:@&=~", c)) {
flags |= T_ESCAPE_PATH_SEGMENT;
}
if (!apr_isalnum(c) && !strchr("$-_.+!*'(),:;@&=/~", c)) {
flags |= T_OS_ESCAPE_PATH;
}
if (!apr_isalnum(c) && !strchr(".-*_ ", c)) {
flags |= T_ESCAPE_URLENCODED;
}
/* Stop for any non-'token' character, including ctrls, obs-text,
* and "tspecials" (RFC2068) a.k.a. "separators" (RFC2616), which
* is easier to express as characters remaining in the ASCII token set
*/
if (!c || !(apr_isalnum(c) || strchr("!#$%&'*+-.^_`|~", c))) {
flags |= T_HTTP_TOKEN_STOP;
}
/* Catch CTRLs other than VCHAR, HT and SP, and obs-text (RFC7230 3.2)
* This includes only the C0 plane, not C1 (which is obs-text itself.)
* XXX: We should verify that all ASCII C0 ctrls/DEL corresponding to
* the current EBCDIC translation are captured, and ASCII C1 ctrls
* corresponding are all permitted (as they fall under obs-text rule)
*/
if (!c || (apr_iscntrl(c) && c != '\t')) {
flags |= T_HTTP_CTRLS;
}
/* From RFC3986, the specific sets of gen-delims, sub-delims (2.2),
* and unreserved (2.3) that are possible somewhere within a URI.
* Spec requires all others to be %XX encoded, including obs-text.
*/
if (c && !apr_iscntrl(c) && c != ' ') {
flags |= T_VCHAR_OBSTEXT;
}
/* For logging, escape all control characters,
* double quotes (because they delimit the request in the log file)
* backslashes (because we use backslash for escaping)
* and 8-bit chars with the high bit set
*/
if (c && (!apr_isprint(c) || c == '"' || c == '\\' || apr_iscntrl(c))) {
flags |= T_ESCAPE_LOGITEM;
}
/* For forensic logging, escape all control characters, top bit set,
* :, | (used as delimiters) and % (used for escaping).
*/
if (!apr_isprint(c) || c == ':' || c == '|' || c == '%'
|| apr_iscntrl(c) || !c) {
flags |= T_ESCAPE_FORENSIC;
}
/* Characters in the RFC 3986 "unreserved" set.
* https://datatracker.ietf.org/doc/html/rfc3986#section-2.3 */
if (c && (apr_isalnum(c) || strchr("-._~", c))) {
flags |= T_URI_UNRESERVED;
}
printf("0x%03x%c", flags, (c < 255) ? ',' : ' ');
}
printf("\n};\n\n");
printf(
"/* we assume the folks using this ensure 0 <= c < 256... which means\n"
" * you need a cast to (unsigned char) first, you can't just plug a\n"
" * char in here and get it to work, because if char is signed then it\n"
" * will first be sign extended.\n"
" */\n"
"#define TEST_CHAR(c, f) (test_char_table[(unsigned char)(c)] & (f))\n"
);
return 0;
}
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