Bounded, case-insensitive WAF-lite checks. More...

#include <cwist/sys/app/waf.h>
#include <cwist/net/http/http.h>
#include <cwist/core/mem/alloc.h>
#include <string.h>
#include <pthread.h>
#include <stdint.h>
#include <stdbool.h>

Include dependency graph for waf.c:

Go to the source code of this file.

Macros
#define	WAF_MAX_PATTERNS 64

#define	WAF_MAX_TEXT 4096

#define	WAF_ALPHABET 128

Functions
bool	cwist_waf_is_safe (const char *input, size_t length)
	Check whether a byte string is free of hostile signatures.

char *	cwist_sanitize_html (const char *input)
	Escape HTML-special characters in a NUL-terminated string.

cwist_middleware_func	cwist_mw_waf_lite (void)
	Construct the WAF-lite middleware.

Detailed Description

Bounded, case-insensitive WAF-lite checks.

Definition in file waf.c.

Macro Definition Documentation

◆ WAF_ALPHABET

#define WAF_ALPHABET 128

Definition at line 44 of file waf.c.

◆ WAF_MAX_PATTERNS

#define WAF_MAX_PATTERNS 64

Definition at line 42 of file waf.c.

◆ WAF_MAX_TEXT

#define WAF_MAX_TEXT 4096

Definition at line 43 of file waf.c.

Function Documentation

◆ cwist_mw_waf_lite()

cwist_middleware_func cwist_mw_waf_lite ( void )

Construct the WAF-lite middleware.

Returns: A middleware function that screens each request with the signature-based WAF checks before invoking the next handler.

Definition at line 218 of file waf.c.

◆ cwist_sanitize_html()

char * cwist_sanitize_html ( const char * input )

Escape HTML-special characters in a NUL-terminated string.

Replaces '&', '<', '>', '"', and '\'' with their HTML entity equivalents and returns a newly allocated buffer holding the escaped text.

Parameters

input Input string; may be NULL.

Returns: Newly allocated, NUL-terminated escaped string that the caller owns and must free with cwist_free, or NULL if input is NULL, on allocation failure, or on size overflow.

Definition at line 141 of file waf.c.

References cap, and cwist_alloc().

◆ cwist_waf_is_safe()

bool cwist_waf_is_safe	(	const char *	input,
		size_t	length
	)

Check whether a byte string is free of hostile signatures.

Scans input once (O(length)) through the case-insensitive Aho-Corasick automaton, which is built lazily on first call. Matching is ASCII-only: bytes at or above 0x80 reset the automaton state, and control bytes other than tab, newline, and carriage return are rejected outright.