/* 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.
*/
/**
* @file apr_escape.h
* @brief APR-UTIL Escaping
*/
#ifndef APR_ESCAPE_H
#define APR_ESCAPE_H
#include "apr.h"
#include "apr_general.h"
#ifdef __cplusplus
extern "C" {
#endif
/**
* @defgroup APR_Util_Escaping Escape functions
* @ingroup APR
* @{
*/
/* Simple escape/unescape functions.
*
* The design goal of these functions are:
*
* - Avoid unnecessary work.
*
* In most cases the strings passed in do not need to be escaped at all. In
* these cases the original string will be returned.
*
* - Lowest possible memory footprint.
*
* The amount of memory allocated for a given encoding is calculated based
* on the exact amount of memory needed, and not the theoretical worst case
* scenario.
*
*/
/**
* When passing a string to one of the escape functions, this value can be
* passed to indicate a string-valued key, and have the length computed
* automatically.
*/
#define APR_ESCAPE_STRING (-1)
/**
* Apply LDAP distinguished name escaping as per RFC4514.
*/
#define APR_ESCAPE_LDAP_DN (0x01)
/**
* Apply LDAP filter escaping as per RFC4515.
*/
#define APR_ESCAPE_LDAP_FILTER (0x02)
/**
* Apply both RFC4514 and RFC4515 LDAP escaping.
*/
#define APR_ESCAPE_LDAP_ALL (0x03)
/**
* Perform shell escaping on the provided string.
*
* Shell escaping causes characters to be prefixed with a '\' character.
* @param escaped Optional buffer to write the encoded string, can be
* NULL
* @param str The original string
* @param slen The length of the original string, or APR_ESCAPE_STRING
* @param len If present, returns the length of the string
* @return APR_SUCCESS, or APR_NOTFOUND if no changes to the string were
* detected or the string was NULL
*/
APR_DECLARE(apr_status_t) apr_escape_shell(char *escaped, const char *str,
apr_ssize_t slen, apr_size_t *len);
/**
* Perform shell escaping on the provided string, returning the result
* from the pool.
*
* Shell escaping causes characters to be prefixed with a '\' character.
*
* If no characters were escaped, the original string is returned.
* @param p Pool to allocate from
* @param str The original string
* @return the encoded string, allocated from the pool, or the original
* string if no escaping took place or the string was NULL.
*/
APR_DECLARE(const char *) apr_pescape_shell(apr_pool_t *p, const char *str)
__attribute__((nonnull(1)));
/**
* Unescapes a URL, leaving reserved characters intact.
* @param escaped Optional buffer to write the encoded string, can be
* NULL
* @param url String to be unescaped
* @param slen The length of the original url, or APR_ESCAPE_STRING
* @param forbid Optional list of forbidden characters, in addition to
* 0x00
* @param reserved Optional list of reserved characters that will be
* left unescaped
* @param plus If non zero, '+' is converted to ' ' as per
* application/x-www-form-urlencoded encoding
* @param len If set, the length of the escaped string will be returned
* @return APR_SUCCESS on success, APR_NOTFOUND if no characters are
* decoded or the string is NULL, APR_EINVAL if a bad escape sequence is
* found, APR_BADCH if a character on the forbid list is found.
*/
APR_DECLARE(apr_status_t) apr_unescape_url(char *escaped, const char *url,
apr_ssize_t slen, const char *forbid, const char *reserved, int plus,
apr_size_t *len);
/**
* Unescapes a URL, leaving reserved characters intact, returning the
* result from a pool.
* @param p Pool to allocate from
* @param url String to be unescaped in place
* @param forbid Optional list of forbidden characters, in addition to
* 0x00
* @param reserved Optional list of reserved characters that will be
* left unescaped
* @param plus If non zero, '+' is converted to ' ' as per
* application/x-www-form-urlencoded encoding
* @return A string allocated from the pool on success, the original string
* if no characters are decoded, or NULL if a bad escape sequence is found
* or if a character on the forbid list is found, or if the original string
* was NULL.
*/
APR_DECLARE(const char *) apr_punescape_url(apr_pool_t *p, const char *url,
const char *forbid, const char *reserved, int plus)
__attribute__((nonnull(1)));
/**
* Escape a path segment, as defined in RFC1808.
* @param escaped Optional buffer to write the encoded string, can be
* NULL
* @param str The original string
* @param slen The length of the original string, or APR_ESCAPE_STRING
* @param len If present, returns the length of the string
* @return APR_SUCCESS, or APR_NOTFOUND if no changes to the string were
* detected or the string was NULL
*/
APR_DECLARE(apr_status_t) apr_escape_path_segment(char *escaped,
const char *str, apr_ssize_t slen, apr_size_t *len);
/**
* Escape a path segment, as defined in RFC1808, returning the result from a
* pool.
* @param p Pool to allocate from
* @param str String to be escaped
* @return A string allocated from the pool on success, the original string
* if no characters are encoded or the string is NULL.
*/
APR_DECLARE(const char *) apr_pescape_path_segment(apr_pool_t *p,
const char *str) __attribute__((nonnull(1)));
/**
* Converts an OS path to a URL, in an OS dependent way, as defined in RFC1808.
* In all cases if a ':' occurs before the first '/' in the URL, the URL should
* be prefixed with "./" (or the ':' escaped). In the case of Unix, this means
* leaving '/' alone, but otherwise doing what escape_path_segment() does. For
* efficiency reasons, we don't use escape_path_segment(), which is provided for
* reference. Again, RFC 1808 is where this stuff is defined.
*
* If partial is set, os_escape_path() assumes that the path will be appended to
* something with a '/' in it (and thus does not prefix "./").
* @param escaped Optional buffer to write the encoded string, can be
* NULL
* @param path The original string
* @param slen The length of the original string, or APR_ESCAPE_STRING
* @param partial If non zero, suppresses the prepending of "./"
* @param len If present, returns the length of the string
* @return APR_SUCCESS, or APR_NOTFOUND if no changes to the string were
* detected or if the string was NULL
*/
APR_DECLARE(apr_status_t) apr_escape_path(char *escaped, const char *path,
apr_ssize_t slen, int partial, apr_size_t *len);
/**
* Converts an OS path to a URL, in an OS dependent way, as defined in RFC1808,
* returning the result from a pool.
*
* In all cases if a ':' occurs before the first '/' in the URL, the URL should
* be prefixed with "./" (or the ':' escaped). In the case of Unix, this means
* leaving '/' alone, but otherwise doing what escape_path_segment() does. For
* efficiency reasons, we don't use escape_path_segment(), which is provided for
* reference. Again, RFC 1808 is where this stuff is defined.
*
* If partial is set, os_escape_path() assumes that the path will be appended to
* something with a '/' in it (and thus does not prefix "./").
* @param p Pool to allocate from
* @param str The original string
* @param partial If non zero, suppresses the prepending of "./"
* @return A string allocated from the pool on success, the original string
* if no characters are encoded or if the string was NULL.
*/
APR_DECLARE(const char *) apr_pescape_path(apr_pool_t *p, const char *str,
int partial) __attribute__((nonnull(1)));
/**
* Urlencode a string, as defined in
* http://www.w3.org/TR/html401/interact/forms.html#h-17.13.4.1.
* @param escaped Optional buffer to write the encoded string, can be
* NULL
* @param str The original string
* @param slen The length of the original string, or APR_ESCAPE_STRING
* @param len If present, returns the length of the string
* @return APR_SUCCESS, or APR_NOTFOUND if no changes to the string were
* detected or if the stirng was NULL
*/
APR_DECLARE(apr_status_t) apr_escape_urlencoded(char *escaped, const char *str,
apr_ssize_t slen, apr_size_t *len);
/**
* Urlencode a string, as defined in
* http://www.w3.org/TR/html401/interact/forms.html#h-17.13.4.1, returning
* the result from a pool.
* @param p Pool to allocate from
* @param str String to be escaped
* @return A string allocated from the pool on success, the original string
* if no characters are encoded or if the string was NULL.
*/
APR_DECLARE(const char *) apr_pescape_urlencoded(apr_pool_t *p,
const char *str) __attribute__((nonnull(1)));
/**
* Apply entity encoding to a string. Characters are replaced as follows:
* '<' becomes '\<', '>' becomes '\>', '&' becomes '\&', the
* double quote becomes '\"" and the single quote becomes '\''.
*
* If toasc is not zero, any non ascii character will be encoded as
* '%\#ddd;', where ddd is the decimal code of the character.
* @param escaped Optional buffer to write the encoded string, can be
* NULL
* @param str The original string
* @param slen The length of the original string, or APR_ESCAPE_STRING
* @param toasc If non zero, encode non ascii characters
* @param len If present, returns the length of the string
* @return APR_SUCCESS, or APR_NOTFOUND if no changes to the string were
* detected or the string was NULL
*/
APR_DECLARE(apr_status_t) apr_escape_entity(char *escaped, const char *str,
apr_ssize_t slen, int toasc, apr_size_t *len);
/**
* Apply entity encoding to a string, returning the result from a pool.
* Characters are replaced as follows: '<' becomes '\<', '>' becomes
* '\>', '&' becomes '\&', the double quote becomes '\"" and the
* single quote becomes '\''.
* @param p Pool to allocate from
* @param str The original string
* @param toasc If non zero, encode non ascii characters
* @return A string allocated from the pool on success, the original string
* if no characters are encoded or the string is NULL.
*/
APR_DECLARE(const char *) apr_pescape_entity(apr_pool_t *p, const char *str,
int toasc) __attribute__((nonnull(1)));
/**
* Decodes html entities or numeric character references in a string. If
* the string to be unescaped is syntactically incorrect, then the
* following fixups will be made:
* unknown entities will be left undecoded;
* references to unused numeric characters will be deleted.
* In particular, � will not be decoded, but will be deleted.
* @param unescaped Optional buffer to write the encoded string, can be
* NULL
* @param str The original string
* @param slen The length of the original string, or APR_ESCAPE_STRING
* @param len If present, returns the length of the string
* @return APR_SUCCESS, or APR_NOTFOUND if no changes to the string were
* detected or the string was NULL
*/
APR_DECLARE(apr_status_t) apr_unescape_entity(char *unescaped, const char *str,
apr_ssize_t slen, apr_size_t *len);
/**
* Decodes html entities or numeric character references in a string. If
* the string to be unescaped is syntactically incorrect, then the
* following fixups will be made:
* unknown entities will be left undecoded;
* references to unused numeric characters will be deleted.
* In particular, � will not be decoded, but will be deleted.
* @param p Pool to allocate from
* @param str The original string
* @return A string allocated from the pool on success, the original string
* if no characters are encoded or the string is NULL.
*/
APR_DECLARE(const char *) apr_punescape_entity(apr_pool_t *p, const char *str)
__attribute__((nonnull(1)));
/**
* Escape control characters in a string, as performed by the shell's
* 'echo' command. Characters are replaced as follows:
* \\a alert (bell), \\b backspace, \\f form feed, \\n new line, \\r carriage
* return, \\t horizontal tab, \\v vertical tab, \\ backslash.
*
* Any non ascii character will be encoded as '\\xHH', where HH is the hex
* code of the character.
*
* If quote is not zero, the double quote character will also be escaped.
* @param escaped Optional buffer to write the encoded string, can be
* NULL
* @param str The original string
* @param slen The length of the original string, or APR_ESCAPE_STRING
* @param quote If non zero, encode double quotes
* @param len If present, returns the length of the string
* @return APR_SUCCESS, or APR_NOTFOUND if no changes to the string were
* detected or the string was NULL
*/
APR_DECLARE(apr_status_t) apr_escape_echo(char *escaped, const char *str,
apr_ssize_t slen, int quote, apr_size_t *len);
/**
* Escape control characters in a string, as performed by the shell's
* 'echo' command, and return the results from a pool. Characters are
* replaced as follows: \\a alert (bell), \\b backspace, \\f form feed,
* \\n new line, \\r carriage return, \\t horizontal tab, \\v vertical tab,
* \\ backslash.
*
* Any non ascii character will be encoded as '\\xHH', where HH is the hex
* code of the character.
*
* If quote is not zero, the double quote character will also be escaped.
* @param p Pool to allocate from
* @param str The original string
* @param quote If non zero, encode double quotes
* @return A string allocated from the pool on success, the original string
* if no characters are encoded or the string is NULL.
*/
APR_DECLARE(const char *) apr_pescape_echo(apr_pool_t *p, const char *str,
int quote);
/**
* Convert binary data to a hex encoding.
* @param dest The destination buffer, can be NULL
* @param src The original buffer
* @param srclen The length of the original buffer
* @param colon If not zero, insert colon characters between hex digits.
* @param len If present, returns the length of the string
* @return APR_SUCCESS, or APR_NOTFOUND if the string was NULL
*/
APR_DECLARE(apr_status_t) apr_escape_hex(char *dest, const void *src,
apr_size_t srclen, int colon, apr_size_t *len);
/**
* Convert binary data to a hex encoding, and return the results from a
* pool.
* @param p Pool to allocate from
* @param src The original buffer
* @param slen The length of the original buffer
* @param colon If not zero, insert colon characters between hex digits.
* @return A zero padded buffer allocated from the pool on success, or
* NULL if src was NULL.
*/
APR_DECLARE(const char *) apr_pescape_hex(apr_pool_t *p, const void *src,
apr_size_t slen, int colon) __attribute__((nonnull(1)));
/**
* Convert hex encoded string to binary data.
* @param dest The destination buffer, can be NULL
* @param str The original buffer
* @param slen The length of the original buffer
* @param colon If not zero, ignore colon characters between hex digits.
* @param len If present, returns the length of the string
* @return APR_SUCCESS, or APR_NOTFOUND if the string was NULL, or APR_BADCH
* if a non hex character is present.
*/
APR_DECLARE(apr_status_t) apr_unescape_hex(void *dest, const char *str,
apr_ssize_t slen, int colon, apr_size_t *len);
/**
* Convert hex encoding to binary data, and return the results from a pool.
* If the colon character appears between pairs of hex digits, it will be
* ignored.
* @param p Pool to allocate from
* @param str The original string
* @param colon If not zero, ignore colon characters between hex digits.
* @param len If present, returns the length of the final buffer
* @return A buffer allocated from the pool on success, or NULL if src was
* NULL, or a bad character was present.
*/
APR_DECLARE(const void *) apr_punescape_hex(apr_pool_t *p, const char *str,
int colon, apr_size_t *len);
/**
* Apply LDAP escaping to binary data. Characters from RFC4514 and RFC4515
* are escaped with their hex equivalents.
* @param dest The destination buffer, can be NULL
* @param src The original buffer
* @param srclen The length of the original buffer
* @param flags APR_ESCAPE_LDAP_DN for RFC4514, APR_ESCAPE_LDAP_FILTER for
* RFC4515, APR_ESCAPE_LDAP_ALL for both
* @param len If present, returns the length of the string
* @return APR_SUCCESS, or APR_NOTFOUND if the string was NULL
*/
APR_DECLARE(apr_status_t) apr_escape_ldap(char *dest, const void *src,
apr_ssize_t srclen, int flags, apr_size_t *len);
/**
* Apply LDAP escaping to binary data, and return the results from a
* pool. Characters from RFC4514 and RFC4515 are escaped with their hex
* equivalents.
* @param p Pool to allocate from
* @param src The original buffer
* @param slen The length of the original buffer
* @param flags APR_ESCAPE_LDAP_DN for RFC4514, APR_ESCAPE_LDAP_FILTER for
* RFC4515, APR_ESCAPE_LDAP_ALL for both
* @return A zero padded buffer allocated from the pool on success, or
* NULL if src was NULL.
*/
APR_DECLARE(const char *) apr_pescape_ldap(apr_pool_t *p, const void *src,
apr_ssize_t slen, int flags) __attribute__((nonnull(1)));
/** @} */
#ifdef __cplusplus
}
#endif
#endif /* !APR_ESCAPE_H */