VFER: src/vsl_util.c File Reference

#include "vsl_api.h"
#include "vsl_util.h"
#include "vsl.h"
#include "../poly1305aes/aes.h"
#include "../poly1305aes/poly1305aes.h"
#include <openssl/md5.h>
#include <openssl/sha.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

Go to the source code of this file.


Functions
void	aes_ctr (unsigned char ctr, const unsigned char key, unsigned char *buf, const size_t len)
void	ctr_inc (unsigned char *ctr)
int	gen_key (unsigned char *key)
uint64_t	htonll (uint64_t val)
void	init_keys_c (vsl_sock sock, const unsigned char key)
void	init_keys_s (vsl_sock sock, const unsigned char key)
bool	is_blocking (vsl_sock *socket)
void	md5 (const unsigned char s1, int l1, const unsigned char s2, int l2, unsigned char *hash)
uint64_t	ntohll (uint64_t val)
unsigned char *	read_objs (unsigned char *src, size_t max,...)
void	set_blocking (vsl_sock *socket, bool mode)
void	sha256 (const unsigned char s1, int l1, const unsigned char s2, int l2, unsigned char *hash)
int	transfer (vsl_sock sock, transmit_fn fn, unsigned char buf, size_t min, size_t len)
unsigned char *	write_objs (size_t *total,...)
void	xor16 (unsigned char b1, unsigned char b2)

Detailed Description

Function Documentation

void aes_ctr	(	unsigned char *	ctr,
		const unsigned char *	key,
		unsigned char *	buf,
		const size_t	len
	)

Encrypts data in AES CTR mode. The counter is modified in place. The first 8 bytes of the counter must contain the nonce and the last 8 bytes should be initialised to zero.

Note that the function cannot be called multiple times without reinitalizing the counter before each invocation.

Parameters:

	ctr	counter
`[in]`	key	encryption key, length VSL_ENC_KEYLEN
	buf	buffer to encrypt
`[in]`	len	length of buffer

Definition at line 344 of file vsl_util.c.

void ctr_inc ( unsigned char * ctr ) [inline]

Increase the counter by one. Uses only the last 8 bytes, aborts in case of an overflow. Works in Little Endian.

Parameters:

ctr

counter to increase

Definition at line 377 of file vsl_util.c.

int gen_key ( unsigned char * key )

Generate a random shared secret of length VSL_KEYLEN

Parameters:

[out] key generated key

Returns:

0 on success

Definition at line 33 of file vsl_util.c.

uint64_t htonll ( uint64_t val ) [inline]

Convert uint64 from host byte order to network byte order.

Parameters:

[in] val value to convert

Returns:: val in network byte order

Definition at line 294 of file vsl_util.c.

void init_keys_c	(	vsl_sock *	sock,
		const unsigned char *	key
	)

Initialize session keys (client mode) from a shared secret.

Parameters:

`[in]`	sock	VSL socket
`[in]`	key	shared secret to generate keys from

Definition at line 63 of file vsl_util.c.

void init_keys_s	(	vsl_sock *	sock,
		const unsigned char *	key
	)

Initialize session keys (server mode) from a shared secret.

Parameters:

`[in]`	sock	VSL socket
`[in]`	key	shared secret to generate keys from

Definition at line 87 of file vsl_util.c.

bool is_blocking ( vsl_sock * socket )

Check whether the underlying vfer fd is blocking

Parameters:

[in] socket VSL socket

Definition at line 144 of file vsl_util.c.

void md5	(	const unsigned char *	s1,
		int	l1,
		const unsigned char *	s2,
		int	l2,
		unsigned char *	hash
	)

Generate a 16 byte MD5 hash of two char arrays

Parameters:

`[in]`	s1	first char array
`[in]`	l1	length of first array
`[in]`	s2	second char array
`[in]`	l2	length of second array
`[out]`	hash	resulting hash (length 16 bytes)

Definition at line 112 of file vsl_util.c.

uint64_t ntohll ( uint64_t val ) [inline]

Convert uint64 from host network order to host byte order.

Parameters:

[in] val value to convert

Returns:: val in network byte order

Definition at line 316 of file vsl_util.c.

unsigned char* read_objs	(	unsigned char *	src,
		size_t	max,
			...
	)

Decomposes a buffer into a number of separate variables.

The variables have to be given as pairs of a void pointer to the variable and an size_t value describing the length of the variable in bytes. The argument list has to be terminated with a NULL pointer. For each pair void* dat, size_t len, the next len bytes of src are copied into dat. After the last object was copied, a pointer to the remainder of src is returned.

Example:

 remainder = read_objs(src,
                       (void*) &data1, sizeof(data1),
                       (void*) &data2, sizeof(data2));

Parameters:

`[in]`	src	source buffer
`[in]`	max	length of source buffer
`[out]`	...	list of alternating `void*` and `size_t` arguments, terminated by `NULL`.

Returns:

pointer into to uncopied remainder of src
NULL the length of the varables was bigger than the source buffer

Definition at line 259 of file vsl_util.c.

void set_blocking	(	vsl_sock *	socket,
		bool	mode
	)

Sets the underlying vfer fd to blocking or nonblocking

Parameters:

`[in]`	socket	VSL socket
`[in]`	mode	whether to block or not

Definition at line 161 of file vsl_util.c.

void sha256	(	const unsigned char *	s1,
		int	l1,
		const unsigned char *	s2,
		int	l2,
		unsigned char *	hash
	)

Generate a 32 byte SHA256 hash of two char arrays

Parameters:

`[in]`	s1	first char array
`[in]`	l1	length of first array
`[in]`	s2	second char array
`[in]`	l2	length of second array
`[out]`	hash	resulting hash (length 32 bytes)

Definition at line 129 of file vsl_util.c.

int transfer	(	vsl_sock *	sock,
		transmit_fn	fn,
		unsigned char *	buf,
		size_t	min,
		size_t	len
	)

Transfer's exactly len (streaming socket) or between min and len (datagram socket) bytes using the specified function (either vfer_send() or vfer_recv()).

Parameters:

`[in]`	sock	socket to use
`[in]`	fn	function to use
	buf	buffer to transmit
`[in]`	min	minimum amount to process for datagram sockets
`[in]`	len	length of buf

Returns:

nr of bytes processed on success

VFER_UNCONN sock is not connected
VFER_INVAL invalid buf or len
VFER_WOULDBLOCK socket is non-blocking and requested operation would block

Definition at line 429 of file vsl_util.c.

unsigned char* write_objs	(	size_t *	total,
			...
	)

Allocates a buffer and writes a sequence of variables into it. The variables have to be given as pairs of a void pointer to the variable and an size_t value describing the length of the variable in bytes. The argument list has to be terminated with a NULL pointer. The total length of the allocated buffer is written into total.

Example:

 buf = write_objs(len,
                  (void*) &data1, sizeof(data1),
                  (void*) &data2, sizeof(data2));

This example allocates a buffer of length sizeof(data1) + sizeof(data2), and writes the objects data1 and data2 into it.

Parameters:

`[out]`	total	total allocated length
`[in]`	...	list of alternating `void*` and `size_t` arguments, terminated by `NULL`.

Returns:

pointer to the allocated buffer
NULL if allocation failed

Definition at line 198 of file vsl_util.c.

void xor16	(	unsigned char *	b1,
		unsigned char *	b2
	)			`[inline]`

XOR 2 16 byte blocks. Argument 1 is modified in place.

Parameters:

	b1	first block
`[in]`	b2	second block

Todo:: Make this 16 byte xor faster

Definition at line 398 of file vsl_util.c.

src/vsl_util.c File Reference

Functions

Detailed Description

Function Documentation