util.h File Reference

Useful utility functions. More...

#include <stdlib.h>
#include <stddef.h>
#include "version.h"

Include dependency graph for util.h:

Go to the source code of this file.

Macros
#define	L8W8JWT_PLATFORM_MALLOC_ALT   0
#define	L8W8JWT_PLATFORM_CALLOC_ALT   0
#define	L8W8JWT_PLATFORM_REALLOC_ALT   0
#define	l8w8jwt_malloc   malloc
#define	l8w8jwt_calloc   calloc
#define	l8w8jwt_realloc   realloc

Functions
L8W8JWT_API int	l8w8jwt_hexstr2bin (const char *hexstr, size_t hexstr_length, unsigned char *output, size_t output_size, size_t *output_length)
L8W8JWT_API int	l8w8jwt_strncmpic (const char *str1, const char *str2, size_t n)
L8W8JWT_API int	l8w8jwt_memcmp (const void *mem1, const void *mem2, size_t n)

Detailed Description

Useful utility functions.

Author

Raphael Beck

Macro Definition Documentation

L8W8JWT_PLATFORM_CALLOC_ALT

#define L8W8JWT_PLATFORM_CALLOC_ALT   0

Set this pre-processor definition to 1 if you need to provide custom implementation of calloc

L8W8JWT_PLATFORM_MALLOC_ALT

#define L8W8JWT_PLATFORM_MALLOC_ALT   0

Set this pre-processor definition to 1 if you need to provide custom implementation of malloc

L8W8JWT_PLATFORM_REALLOC_ALT

#define L8W8JWT_PLATFORM_REALLOC_ALT   0

Set this pre-processor definition to 1 if you need to provide custom implementation of realloc

Function Documentation

l8w8jwt_hexstr2bin()

L8W8JWT_API int l8w8jwt_hexstr2bin	(	const char *	hexstr,
		size_t	hexstr_length,
		unsigned char *	output,
		size_t	output_size,
		size_t *	output_length
	)

Converts a hex-encoded string to a binary array.

A NUL-terminator is appended at the end of the output buffer, so make sure to allocate at least (hexstr_length / 2) + 1 bytes!

Parameters

hexstr	The hex string to convert.
hexstr_length	Length of the hexstr
output	Where to write the converted binary data into.
output_size	Size of the output buffer (make sure to allocate at least (hexstr_length / 2) + 1 bytes!).
output_length	[OPTIONAL] Where to write the output array length into. This is always gonna be hexstr_length / 2, but you can still choose to write it out just to be sure. If you want to omit this: no problem.. just pass NULL!

Returns

0 if conversion succeeded. 1 if one or more required arguments were NULL or invalid. 2 if the hexadecimal string is in an invalid format (e.g. not divisible by 2). 3 if output buffer size was insufficient (needs to be at least (hexstr_length / 2) + 1 bytes).

l8w8jwt_memcmp()

L8W8JWT_API int l8w8jwt_memcmp	(	const void *	mem1,
		const void *	mem2,
		size_t	n
	)

Compares two blocks of memory against equality in a cryptographically safe manner (time-safe impl./constant-time comparison).

Parameters

mem1	Memory block 1 to compare.
mem2	Memory block 2 to compare.
n	How many bytes to compare.

Returns

Returns 0 if the two memory blocks are equal for the passed amount of bytes.

l8w8jwt_strncmpic()

L8W8JWT_API int l8w8jwt_strncmpic	(	const char *	str1,
		const char *	str2,
		size_t	n
	)

Compares two strings ignoring UPPER vs. lowercase.

Parameters

str1	String to compare.
str2	String to compare to.
n	How many characters of the string should be compared (starting from index 0)?

Returns

If the strings are equal, 0 is returned. Otherwise, something else.