1 /*
2  * Copyright (C) 1996-2021 The Squid Software Foundation and contributors
3  *
4  * Squid software is distributed under GPLv2+ license and includes
5  * contributions from numerous individuals and organizations.
6  * Please see the COPYING and CONTRIBUTORS files for details.
7  */
8 
9 #ifndef _SQUID_INCLUDE_RFC1738_H
10 #define _SQUID_INCLUDE_RFC1738_H
11 
12 #ifdef __cplusplus
13 extern "C" {
14 #endif
15 
16 /* Encoder rfc1738_do_escape flag values. */
17 #define RFC1738_ESCAPE_CTRLS       1
18 #define RFC1738_ESCAPE_UNSAFE      2
19 #define RFC1738_ESCAPE_RESERVED    4
20 #define RFC1738_ESCAPE_ALL         (RFC1738_ESCAPE_UNSAFE|RFC1738_ESCAPE_RESERVED|RFC1738_ESCAPE_CTRLS)
21 // exclusions
22 #define RFC1738_ESCAPE_NOSPACE     128
23 #define RFC1738_ESCAPE_NOPERCENT   256
24 // Backward compatibility
25 #define RFC1738_ESCAPE_UNESCAPED   (RFC1738_ESCAPE_UNSAFE|RFC1738_ESCAPE_CTRLS|RFC1738_ESCAPE_NOPERCENT)
26 
27 /**
28  * \group rfc1738 RFC 1738 URL-escaping library
29  *
30  * Public API is formed of a triplet of encode functions mapping to the rfc1738_do_encode() engine.
31  *
32  * ASCII characters are split into four groups:
33  * \item SAFE     Characters which are safe to occur in any URL. For example A,B,C
34  * \item CTRLS    Binary control codes. Dangerous to include in URLs.
35  * \item UNSAFE   Characters which are completely usafe to occur in any URL. For example; backspace, tab, space, newline.
36  * \item RESERVED Characters which are reserved for special meaning and may only occur in certain parts of a URL.
37  *
38  * Returns a static buffer containing the RFC 1738 compliant, escaped version of the given url.
39  *
40  * \param flags  RFC1738_ESCAPE_CTRLS     Encode the blatantly dangerous binary codes.
41  * \param flags  RFC1738_ESCAPE_UNSAFE    Encode printable unsafe characters (excluding CTRLs).
42  * \param flags  RFC1738_ESCAPE_RESERVED  Encode reserved characters.
43  * \param flags  RFC1738_ESCAPE_ALL       Encode all binary CTRL, unsafe and reserved characters.
44  * \param flags  RFC1738_ESCAPE_NOSPACE   Ignore the space whitespace character.
45  * \param flags  RFC1738_ESCAPE_NOPERCENT Ignore the escaping delimiter '%'.
46  */
47 extern char *rfc1738_do_escape(const char *url, int flags);
48 
49 /* Old API functions */
50 
51 /* Default RFC 1738 escaping. Escape all UNSAFE characters and binary CTRL codes */
52 #define rfc1738_escape(x)  rfc1738_do_escape(x, RFC1738_ESCAPE_UNSAFE|RFC1738_ESCAPE_CTRLS)
53 
54 /* Escape a partial URL. Encoding every binary code, unsafe or reserved character. */
55 #define rfc1738_escape_part(x)  rfc1738_do_escape(x, RFC1738_ESCAPE_ALL)
56 
57 /* Escape a URL. Encoding every unsafe characters but skipping reserved and already-encoded bytes.
58  * Suitable for safely encoding an absolute URL which may be encoded but is not trusted. */
59 #define rfc1738_escape_unescaped(x)  rfc1738_do_escape(x, RFC1738_ESCAPE_UNSAFE|RFC1738_ESCAPE_CTRLS|RFC1738_ESCAPE_NOPERCENT)
60 
61 /**
62  * Unescape a URL string according to RFC 1738 specification.
63  * String is unescaped in-place
64  */
65 extern void rfc1738_unescape(char *url);
66 
67 #ifdef __cplusplus
68 }
69 #endif
70 #endif /* _SQUID_INCLUDE_RFC1738_H */
71 
72