/* 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 "apu.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 */