zephyr/net/ip/tinydtls/global.h

148 lines
4.3 KiB
C

/* dtls -- a very basic DTLS implementation
*
* Copyright (C) 2011--2014 Olaf Bergmann <bergmann@tzi.org>
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy,
* modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#ifndef _DTLS_GLOBAL_H_
#define _DTLS_GLOBAL_H_
#include <stdlib.h>
#include <sys/types.h>
#include "tinydtls.h"
#ifndef DTLSv12
/* The current version of tinyDTLS supports DTLSv1.2 only. */
#define DTLSv12 1
#endif
#ifndef WITH_SHA256
/* The current version of tinyDTLS supports DTLSv1.2 with SHA256 PRF
only. */
#define WITH_SHA256 1
#endif
/* Define our own types as at least uint32_t does not work on my amd64. */
typedef unsigned char uint8;
typedef unsigned char uint16[2];
typedef unsigned char uint24[3];
typedef unsigned char uint32[4];
typedef unsigned char uint48[6];
#ifndef DTLS_MAX_BUF
/** Maximum size of DTLS message.
When Peers are sending bigger messages this causes problems. Californium
with ECDSA needs at least 220 */
#ifdef WITH_CONTIKI
#ifdef DTLS_ECC
#define DTLS_MAX_BUF 200
#else /* DTLS_ECC */
#define DTLS_MAX_BUF 100
#endif /* DTLS_ECC */
#else /* WITH_CONTIKI */
#define DTLS_MAX_BUF 1400
#endif /* WITH_CONTIKI */
#endif
#ifndef DTLS_DEFAULT_MAX_RETRANSMIT
/** Number of message retransmissions. */
#define DTLS_DEFAULT_MAX_RETRANSMIT 7
#endif
/** Known cipher suites.*/
typedef enum {
TLS_NULL_WITH_NULL_NULL = 0x0000, /**< NULL cipher */
TLS_PSK_WITH_AES_128_CCM_8 = 0xC0A8, /**< see RFC 6655 */
TLS_ECDHE_ECDSA_WITH_AES_128_CCM_8 = 0xC0AE /**< see RFC 7251 */
} dtls_cipher_t;
/** Known compression suites.*/
typedef enum {
TLS_COMPRESSION_NULL = 0x0000 /* NULL compression */
} dtls_compression_t;
#define TLS_EXT_ELLIPTIC_CURVES 10 /* see RFC 4492 */
#define TLS_EXT_EC_POINT_FORMATS 11 /* see RFC 4492 */
#define TLS_EXT_SIG_HASH_ALGO 13 /* see RFC 5246 */
#define TLS_EXT_CLIENT_CERTIFICATE_TYPE 19 /* see RFC 7250 */
#define TLS_EXT_SERVER_CERTIFICATE_TYPE 20 /* see RFC 7250 */
#define TLS_EXT_ENCRYPT_THEN_MAC 22 /* see RFC 7366 */
#define TLS_CERT_TYPE_RAW_PUBLIC_KEY 2 /* see RFC 7250 */
#define TLS_EXT_ELLIPTIC_CURVES_SECP256R1 23 /* see RFC 4492 */
#define TLS_EXT_EC_POINT_FORMATS_UNCOMPRESSED 0 /* see RFC 4492 */
#define TLS_EC_CURVE_TYPE_NAMED_CURVE 3 /* see RFC 4492 */
#define TLS_CLIENT_CERTIFICATE_TYPE_ECDSA_SIGN 64 /* see RFC 4492 */
#define TLS_EXT_SIG_HASH_ALGO_SHA256 4 /* see RFC 5246 */
#define TLS_EXT_SIG_HASH_ALGO_ECDSA 3 /* see RFC 5246 */
/**
* XORs \p n bytes byte-by-byte starting at \p y to the memory area
* starting at \p x. */
static inline void
memxor(unsigned char *x, const unsigned char *y, size_t n) {
while(n--) {
*x ^= *y;
x++; y++;
}
}
/**
* Compares \p len bytes from @p a with @p b in constant time. This
* functions always traverses the entire length to prevent timing
* attacks.
*
* \param a Byte sequence to compare
* \param b Byte sequence to compare
* \param len Number of bytes to compare.
* \return \c 1 if \p a and \p b are equal, \c 0 otherwise.
*/
static inline int
equals(unsigned char *a, unsigned char *b, size_t len) {
int result = 1;
while (len--) {
result &= (*a++ == *b++);
}
return result;
}
#ifdef HAVE_FLS
#define dtls_fls(i) fls(i)
#else
static inline int
dtls_fls(unsigned int i) {
int n;
for (n = 0; i; n++)
i >>= 1;
return n;
}
#endif /* HAVE_FLS */
#endif /* _DTLS_GLOBAL_H_ */