ZeroTierOne/node/Utils.hpp
Léo El Amri 1aa31e0414 Fix how MAC addresses are handled by the rules parser
It wasn't ignoring separator characters such as the colon and hyphen.
The rules compiler automatically add a colon to separate bytes, which is
not compatible with how they are parsed.
2023-11-15 16:51:03 +01:00

870 lines
22 KiB
C++

/*
* Copyright (c)2019 ZeroTier, Inc.
*
* Use of this software is governed by the Business Source License included
* in the LICENSE.TXT file in the project's root directory.
*
* Change Date: 2025-01-01
*
* On the date above, in accordance with the Business Source License, use
* of this software will be governed by version 2.0 of the Apache License.
*/
/****/
#ifndef ZT_UTILS_HPP
#define ZT_UTILS_HPP
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <time.h>
#include <string>
#include <stdexcept>
#include <vector>
#include <map>
#include <algorithm>
#if defined(__FreeBSD__)
#include <sys/endian.h>
#endif
#include "Constants.hpp"
#if __BYTE_ORDER == __LITTLE_ENDIAN
#define ZT_CONST_TO_BE_UINT16(x) ((uint16_t)((uint16_t)((uint16_t)(x) << 8U) | (uint16_t)((uint16_t)(x) >> 8U)))
#define ZT_CONST_TO_BE_UINT64(x) ( \
(((uint64_t)(x) & 0x00000000000000ffULL) << 56U) | \
(((uint64_t)(x) & 0x000000000000ff00ULL) << 40U) | \
(((uint64_t)(x) & 0x0000000000ff0000ULL) << 24U) | \
(((uint64_t)(x) & 0x00000000ff000000ULL) << 8U) | \
(((uint64_t)(x) & 0x000000ff00000000ULL) >> 8U) | \
(((uint64_t)(x) & 0x0000ff0000000000ULL) >> 24U) | \
(((uint64_t)(x) & 0x00ff000000000000ULL) >> 40U) | \
(((uint64_t)(x) & 0xff00000000000000ULL) >> 56U))
#else
#define ZT_CONST_TO_BE_UINT16(x) ((uint16_t)(x))
#define ZT_CONST_TO_BE_UINT64(x) ((uint64_t)(x))
#endif
#define ZT_ROR64(x, r) (((x) >> (r)) | ((x) << (64 - (r))))
#define ZT_ROL64(x, r) (((x) << (r)) | ((x) >> (64 - (r))))
#define ZT_ROR32(x, r) (((x) >> (r)) | ((x) << (32 - (r))))
#define ZT_ROL32(x, r) (((x) << (r)) | ((x) >> (32 - (r))))
namespace ZeroTier {
/**
* Miscellaneous utility functions and global constants
*/
class Utils
{
public:
static const uint64_t ZERO256[4];
#ifdef ZT_ARCH_ARM_HAS_NEON
struct ARMCapabilities
{
ARMCapabilities() noexcept;
bool aes;
bool crc32;
bool pmull;
bool sha1;
bool sha2;
};
static const ARMCapabilities ARMCAP;
#endif
#ifdef ZT_ARCH_X64
struct CPUIDRegisters
{
CPUIDRegisters() noexcept;
bool rdrand;
bool aes;
bool avx;
bool vaes; // implies AVX
bool vpclmulqdq; // implies AVX
bool avx2;
bool avx512f;
bool sha;
bool fsrm;
};
static const CPUIDRegisters CPUID;
#endif
/**
* Compute the log2 (most significant bit set) of a 32-bit integer
*
* @param v Integer to compute
* @return log2 or 0 if v is 0
*/
static inline unsigned int log2(uint32_t v)
{
uint32_t r = (v > 0xffff) << 4;
v >>= r;
uint32_t shift = (v > 0xff) << 3;
v >>= shift;
r |= shift;
shift = (v > 0xf) << 2;
v >>= shift;
r |= shift;
shift = (v > 0x3) << 1;
v >>= shift;
r |= shift;
r |= (v >> 1);
return (unsigned int)r;
}
/**
* Perform a time-invariant binary comparison
*
* @param a First binary string
* @param b Second binary string
* @param len Length of strings
* @return True if strings are equal
*/
static inline bool secureEq(const void *a,const void *b,unsigned int len)
{
uint8_t diff = 0;
for(unsigned int i=0;i<len;++i) {
diff |= ( (reinterpret_cast<const uint8_t *>(a))[i] ^ (reinterpret_cast<const uint8_t *>(b))[i] );
}
return (diff == 0);
}
/**
* Securely zero memory, avoiding compiler optimizations and such
*/
static void burn(void *ptr,unsigned int len);
/**
* @param n Number to convert
* @param s Buffer, at least 24 bytes in size
* @return String containing 'n' in base 10 form
*/
static char *decimal(unsigned long n,char s[24]);
static inline char *hex(uint64_t i,char s[17])
{
s[0] = HEXCHARS[(i >> 60) & 0xf];
s[1] = HEXCHARS[(i >> 56) & 0xf];
s[2] = HEXCHARS[(i >> 52) & 0xf];
s[3] = HEXCHARS[(i >> 48) & 0xf];
s[4] = HEXCHARS[(i >> 44) & 0xf];
s[5] = HEXCHARS[(i >> 40) & 0xf];
s[6] = HEXCHARS[(i >> 36) & 0xf];
s[7] = HEXCHARS[(i >> 32) & 0xf];
s[8] = HEXCHARS[(i >> 28) & 0xf];
s[9] = HEXCHARS[(i >> 24) & 0xf];
s[10] = HEXCHARS[(i >> 20) & 0xf];
s[11] = HEXCHARS[(i >> 16) & 0xf];
s[12] = HEXCHARS[(i >> 12) & 0xf];
s[13] = HEXCHARS[(i >> 8) & 0xf];
s[14] = HEXCHARS[(i >> 4) & 0xf];
s[15] = HEXCHARS[i & 0xf];
s[16] = (char)0;
return s;
}
static inline char *hex10(uint64_t i,char s[11])
{
s[0] = HEXCHARS[(i >> 36) & 0xf];
s[1] = HEXCHARS[(i >> 32) & 0xf];
s[2] = HEXCHARS[(i >> 28) & 0xf];
s[3] = HEXCHARS[(i >> 24) & 0xf];
s[4] = HEXCHARS[(i >> 20) & 0xf];
s[5] = HEXCHARS[(i >> 16) & 0xf];
s[6] = HEXCHARS[(i >> 12) & 0xf];
s[7] = HEXCHARS[(i >> 8) & 0xf];
s[8] = HEXCHARS[(i >> 4) & 0xf];
s[9] = HEXCHARS[i & 0xf];
s[10] = (char)0;
return s;
}
static inline char *hex(uint32_t i,char s[9])
{
s[0] = HEXCHARS[(i >> 28) & 0xf];
s[1] = HEXCHARS[(i >> 24) & 0xf];
s[2] = HEXCHARS[(i >> 20) & 0xf];
s[3] = HEXCHARS[(i >> 16) & 0xf];
s[4] = HEXCHARS[(i >> 12) & 0xf];
s[5] = HEXCHARS[(i >> 8) & 0xf];
s[6] = HEXCHARS[(i >> 4) & 0xf];
s[7] = HEXCHARS[i & 0xf];
s[8] = (char)0;
return s;
}
static inline char *hex(uint16_t i,char s[5])
{
s[0] = HEXCHARS[(i >> 12) & 0xf];
s[1] = HEXCHARS[(i >> 8) & 0xf];
s[2] = HEXCHARS[(i >> 4) & 0xf];
s[3] = HEXCHARS[i & 0xf];
s[4] = (char)0;
return s;
}
static inline char *hex(uint8_t i,char s[3])
{
s[0] = HEXCHARS[(i >> 4) & 0xf];
s[1] = HEXCHARS[i & 0xf];
s[2] = (char)0;
return s;
}
static inline char *hex(const void *d,unsigned int l,char *s)
{
char *const save = s;
for(unsigned int i=0;i<l;++i) {
const unsigned int b = reinterpret_cast<const uint8_t *>(d)[i];
*(s++) = HEXCHARS[b >> 4];
*(s++) = HEXCHARS[b & 0xf];
}
*s = (char)0;
return save;
}
static inline unsigned int unhex(const char *h,void *buf,unsigned int buflen)
{
unsigned int l = 0;
while (l < buflen) {
uint8_t hc = *(reinterpret_cast<const uint8_t *>(h++));
if (!hc) {
break;
}
uint8_t c = 0;
if ((hc >= 48)&&(hc <= 57)) { // 0..9
c = hc - 48;
} else if ((hc >= 97)&&(hc <= 102)) { // a..f
c = hc - 87;
} else if ((hc >= 65)&&(hc <= 70)) { // A..F
c = hc - 55;
}
hc = *(reinterpret_cast<const uint8_t *>(h++));
if (!hc) {
break;
}
c <<= 4;
if ((hc >= 48)&&(hc <= 57)) {
c |= hc - 48;
} else if ((hc >= 97)&&(hc <= 102)) {
c |= hc - 87;
} else if ((hc >= 65)&&(hc <= 70)) {
c |= hc - 55;
}
reinterpret_cast<uint8_t *>(buf)[l++] = c;
}
return l;
}
static inline unsigned int unhex(const char *h,unsigned int hlen,void *buf,unsigned int buflen)
{
unsigned int l = 0;
const char *hend = h + hlen;
while (l < buflen) {
if (h == hend) {
break;
}
uint8_t hc = *(reinterpret_cast<const uint8_t *>(h++));
if (!hc) {
break;
}
uint8_t c = 0;
if ((hc >= 48)&&(hc <= 57)) {
c = hc - 48;
} else if ((hc >= 97)&&(hc <= 102)) {
c = hc - 87;
} else if ((hc >= 65)&&(hc <= 70)) {
c = hc - 55;
}
if (h == hend) {
break;
}
hc = *(reinterpret_cast<const uint8_t *>(h++));
if (!hc) {
break;
}
c <<= 4;
if ((hc >= 48)&&(hc <= 57)) {
c |= hc - 48;
} else if ((hc >= 97)&&(hc <= 102)) {
c |= hc - 87;
} else if ((hc >= 65)&&(hc <= 70)) {
c |= hc - 55;
}
reinterpret_cast<uint8_t *>(buf)[l++] = c;
}
return l;
}
static inline float normalize(float value, float bigMin, float bigMax, float targetMin, float targetMax)
{
float bigSpan = bigMax - bigMin;
float smallSpan = targetMax - targetMin;
float valueScaled = (value - bigMin) / bigSpan;
return targetMin + valueScaled * smallSpan;
}
/**
* Generate secure random bytes
*
* This will try to use whatever OS sources of entropy are available. It's
* guarded by an internal mutex so it's thread-safe.
*
* @param buf Buffer to fill
* @param bytes Number of random bytes to generate
*/
static void getSecureRandom(void *buf,unsigned int bytes);
/**
* Tokenize a string (alias for strtok_r or strtok_s depending on platform)
*
* @param str String to split
* @param delim Delimiters
* @param saveptr Pointer to a char * for temporary reentrant storage
*/
static inline char *stok(char *str,const char *delim,char **saveptr)
{
#ifdef __WINDOWS__
return strtok_s(str,delim,saveptr);
#else
return strtok_r(str,delim,saveptr);
#endif
}
static inline unsigned int strToUInt(const char *s) { return (unsigned int)strtoul(s,(char **)0,10); }
static inline int strToInt(const char *s) { return (int)strtol(s,(char **)0,10); }
static inline unsigned long strToULong(const char *s) { return strtoul(s,(char **)0,10); }
static inline long strToLong(const char *s) { return strtol(s,(char **)0,10); }
static inline double strToDouble(const char *s) { return strtod(s,NULL); }
static inline unsigned long long strToU64(const char *s)
{
#ifdef __WINDOWS__
return (unsigned long long)_strtoui64(s,(char **)0,10);
#else
return strtoull(s,(char **)0,10);
#endif
}
static inline long long strTo64(const char *s)
{
#ifdef __WINDOWS__
return (long long)_strtoi64(s,(char **)0,10);
#else
return strtoll(s,(char **)0,10);
#endif
}
static inline unsigned int hexStrToUInt(const char *s) { return (unsigned int)strtoul(s,(char **)0,16); }
static inline int hexStrToInt(const char *s) { return (int)strtol(s,(char **)0,16); }
static inline unsigned long hexStrToULong(const char *s) { return strtoul(s,(char **)0,16); }
static inline long hexStrToLong(const char *s) { return strtol(s,(char **)0,16); }
static inline unsigned long long hexStrToU64(const char *s)
{
#ifdef __WINDOWS__
return (unsigned long long)_strtoui64(s,(char **)0,16);
#else
return strtoull(s,(char **)0,16);
#endif
}
static inline long long hexStrTo64(const char *s)
{
#ifdef __WINDOWS__
return (long long)_strtoi64(s,(char **)0,16);
#else
return strtoll(s,(char **)0,16);
#endif
}
/**
* Perform a safe C string copy, ALWAYS null-terminating the result
*
* This will never ever EVER result in dest[] not being null-terminated
* regardless of any input parameter (other than len==0 which is invalid).
*
* @param dest Destination buffer (must not be NULL)
* @param len Length of dest[] (if zero, false is returned and nothing happens)
* @param src Source string (if NULL, dest will receive a zero-length string and true is returned)
* @return True on success, false on overflow (buffer will still be 0-terminated)
*/
static inline bool scopy(char *dest,unsigned int len,const char *src)
{
if (!len) {
return false; // sanity check
}
if (!src) {
*dest = (char)0;
return true;
}
char *end = dest + len;
while ((*dest++ = *src++)) {
if (dest == end) {
*(--dest) = (char)0;
return false;
}
}
return true;
}
/**
* Count the number of bits set in an integer
*
* @param v 32-bit integer
* @return Number of bits set in this integer (0-32)
*/
static inline uint32_t countBits(uint32_t v)
{
v = v - ((v >> 1) & (uint32_t)0x55555555);
v = (v & (uint32_t)0x33333333) + ((v >> 2) & (uint32_t)0x33333333);
return ((((v + (v >> 4)) & (uint32_t)0xF0F0F0F) * (uint32_t)0x1010101) >> 24);
}
/**
* Count the number of bits set in an integer
*
* @param v 64-bit integer
* @return Number of bits set in this integer (0-64)
*/
static inline uint64_t countBits(uint64_t v)
{
v = v - ((v >> 1) & (uint64_t)~(uint64_t)0/3);
v = (v & (uint64_t)~(uint64_t)0/15*3) + ((v >> 2) & (uint64_t)~(uint64_t)0/15*3);
v = (v + (v >> 4)) & (uint64_t)~(uint64_t)0/255*15;
return (uint64_t)(v * ((uint64_t)~(uint64_t)0/255)) >> 56;
}
/**
* Check if a memory buffer is all-zero
*
* @param p Memory to scan
* @param len Length of memory
* @return True if memory is all zero
*/
static inline bool isZero(const void *p,unsigned int len)
{
for(unsigned int i=0;i<len;++i) {
if (((const unsigned char *)p)[i]) {
return false;
}
}
return true;
}
/**
* Unconditionally swap bytes regardless of host byte order
*
* @param n Integer to swap
* @return Integer with bytes reversed
*/
static ZT_INLINE uint64_t swapBytes(const uint64_t n) noexcept
{
#ifdef __GNUC__
return __builtin_bswap64(n);
#else
#ifdef _MSC_VER
return (uint64_t)_byteswap_uint64((unsigned __int64)n);
#else
return (
((n & 0x00000000000000ffULL) << 56) |
((n & 0x000000000000ff00ULL) << 40) |
((n & 0x0000000000ff0000ULL) << 24) |
((n & 0x00000000ff000000ULL) << 8) |
((n & 0x000000ff00000000ULL) >> 8) |
((n & 0x0000ff0000000000ULL) >> 24) |
((n & 0x00ff000000000000ULL) >> 40) |
((n & 0xff00000000000000ULL) >> 56)
);
#endif
#endif
}
/**
* Unconditionally swap bytes regardless of host byte order
*
* @param n Integer to swap
* @return Integer with bytes reversed
*/
static ZT_INLINE uint32_t swapBytes(const uint32_t n) noexcept
{
#if defined(__GNUC__)
return __builtin_bswap32(n);
#else
#ifdef _MSC_VER
return (uint32_t)_byteswap_ulong((unsigned long)n);
#else
return htonl(n);
#endif
#endif
}
/**
* Unconditionally swap bytes regardless of host byte order
*
* @param n Integer to swap
* @return Integer with bytes reversed
*/
static ZT_INLINE uint16_t swapBytes(const uint16_t n) noexcept
{
#if defined(__GNUC__)
return __builtin_bswap16(n);
#else
#ifdef _MSC_VER
return (uint16_t)_byteswap_ushort((unsigned short)n);
#else
return htons(n);
#endif
#endif
}
// These are helper adapters to load and swap integer types special cased by size
// to work with all typedef'd variants, signed/unsigned, etc.
template< typename I, unsigned int S >
class _swap_bytes_bysize;
template< typename I >
class _swap_bytes_bysize< I, 1 >
{
public:
static ZT_INLINE I s(const I n) noexcept
{ return n; }
};
template< typename I >
class _swap_bytes_bysize< I, 2 >
{
public:
static ZT_INLINE I s(const I n) noexcept
{ return (I)swapBytes((uint16_t)n); }
};
template< typename I >
class _swap_bytes_bysize< I, 4 >
{
public:
static ZT_INLINE I s(const I n) noexcept
{ return (I)swapBytes((uint32_t)n); }
};
template< typename I >
class _swap_bytes_bysize< I, 8 >
{
public:
static ZT_INLINE I s(const I n) noexcept
{ return (I)swapBytes((uint64_t)n); }
};
template< typename I, unsigned int S >
class _load_be_bysize;
template< typename I >
class _load_be_bysize< I, 1 >
{
public:
static ZT_INLINE I l(const uint8_t *const p) noexcept
{ return p[0]; }
};
template< typename I >
class _load_be_bysize< I, 2 >
{
public:
static ZT_INLINE I l(const uint8_t *const p) noexcept
{ return (I)(((unsigned int)p[0] << 8U) | (unsigned int)p[1]); }
};
template< typename I >
class _load_be_bysize< I, 4 >
{
public:
static ZT_INLINE I l(const uint8_t *const p) noexcept
{ return (I)(((uint32_t)p[0] << 24U) | ((uint32_t)p[1] << 16U) | ((uint32_t)p[2] << 8U) | (uint32_t)p[3]); }
};
template< typename I >
class _load_be_bysize< I, 8 >
{
public:
static ZT_INLINE I l(const uint8_t *const p) noexcept
{ return (I)(((uint64_t)p[0] << 56U) | ((uint64_t)p[1] << 48U) | ((uint64_t)p[2] << 40U) | ((uint64_t)p[3] << 32U) | ((uint64_t)p[4] << 24U) | ((uint64_t)p[5] << 16U) | ((uint64_t)p[6] << 8U) | (uint64_t)p[7]); }
};
template< typename I, unsigned int S >
class _load_le_bysize;
template< typename I >
class _load_le_bysize< I, 1 >
{
public:
static ZT_INLINE I l(const uint8_t *const p) noexcept
{ return p[0]; }
};
template< typename I >
class _load_le_bysize< I, 2 >
{
public:
static ZT_INLINE I l(const uint8_t *const p) noexcept
{ return (I)((unsigned int)p[0] | ((unsigned int)p[1] << 8U)); }
};
template< typename I >
class _load_le_bysize< I, 4 >
{
public:
static ZT_INLINE I l(const uint8_t *const p) noexcept
{ return (I)((uint32_t)p[0] | ((uint32_t)p[1] << 8U) | ((uint32_t)p[2] << 16U) | ((uint32_t)p[3] << 24U)); }
};
template< typename I >
class _load_le_bysize< I, 8 >
{
public:
static ZT_INLINE I l(const uint8_t *const p) noexcept
{ return (I)((uint64_t)p[0] | ((uint64_t)p[1] << 8U) | ((uint64_t)p[2] << 16U) | ((uint64_t)p[3] << 24U) | ((uint64_t)p[4] << 32U) | ((uint64_t)p[5] << 40U) | ((uint64_t)p[6] << 48U) | ((uint64_t)p[7]) << 56U); }
};
/**
* Convert any signed or unsigned integer type to big-endian ("network") byte order
*
* @tparam I Integer type (usually inferred)
* @param n Value to convert
* @return Value in big-endian order
*/
template< typename I >
static ZT_INLINE I hton(const I n) noexcept
{
#if __BYTE_ORDER == __LITTLE_ENDIAN
return _swap_bytes_bysize< I, sizeof(I) >::s(n);
#else
return n;
#endif
}
/**
* Convert any signed or unsigned integer type to host byte order from big-endian ("network") byte order
*
* @tparam I Integer type (usually inferred)
* @param n Value to convert
* @return Value in host byte order
*/
template< typename I >
static ZT_INLINE I ntoh(const I n) noexcept
{
#if __BYTE_ORDER == __LITTLE_ENDIAN
return _swap_bytes_bysize< I, sizeof(I) >::s(n);
#else
return n;
#endif
}
/**
* Copy bits from memory into an integer type without modifying their order
*
* @tparam I Type to load
* @param p Byte stream, must be at least sizeof(I) in size
* @return Loaded raw integer
*/
template< typename I >
static ZT_INLINE I loadMachineEndian(const void *const p) noexcept
{
#ifdef ZT_NO_UNALIGNED_ACCESS
I tmp;
for(int i=0;i<(int)sizeof(I);++i) {
reinterpret_cast<uint8_t *>(&tmp)[i] = reinterpret_cast<const uint8_t *>(p)[i];
}
return tmp;
#else
return *reinterpret_cast<const I *>(p);
#endif
}
/**
* Copy bits from memory into an integer type without modifying their order
*
* @tparam I Type to store
* @param p Byte array (must be at least sizeof(I))
* @param i Integer to store
*/
template< typename I >
static ZT_INLINE void storeMachineEndian(void *const p, const I i) noexcept
{
#ifdef ZT_NO_UNALIGNED_ACCESS
for(unsigned int k=0;k<sizeof(I);++k) {
reinterpret_cast<uint8_t *>(p)[k] = reinterpret_cast<const uint8_t *>(&i)[k];
}
#else
*reinterpret_cast<I *>(p) = i;
#endif
}
/**
* Decode a big-endian value from a byte stream
*
* @tparam I Type to decode (should be unsigned e.g. uint32_t or uint64_t)
* @param p Byte stream, must be at least sizeof(I) in size
* @return Decoded integer
*/
template< typename I >
static ZT_INLINE I loadBigEndian(const void *const p) noexcept
{
#ifdef ZT_NO_UNALIGNED_ACCESS
return _load_be_bysize<I,sizeof(I)>::l(reinterpret_cast<const uint8_t *>(p));
#else
return ntoh(*reinterpret_cast<const I *>(p));
#endif
}
/**
* Save an integer in big-endian format
*
* @tparam I Integer type to store (usually inferred)
* @param p Byte stream to write (must be at least sizeof(I))
* #param i Integer to write
*/
template< typename I >
static ZT_INLINE void storeBigEndian(void *const p, I i) noexcept
{
#ifdef ZT_NO_UNALIGNED_ACCESS
storeMachineEndian(p,hton(i));
#else
*reinterpret_cast<I *>(p) = hton(i);
#endif
}
/**
* Decode a little-endian value from a byte stream
*
* @tparam I Type to decode
* @param p Byte stream, must be at least sizeof(I) in size
* @return Decoded integer
*/
template< typename I >
static ZT_INLINE I loadLittleEndian(const void *const p) noexcept
{
#if __BYTE_ORDER == __BIG_ENDIAN || defined(ZT_NO_UNALIGNED_ACCESS)
return _load_le_bysize<I,sizeof(I)>::l(reinterpret_cast<const uint8_t *>(p));
#else
return *reinterpret_cast<const I *>(p);
#endif
}
/**
* Save an integer in little-endian format
*
* @tparam I Integer type to store (usually inferred)
* @param p Byte stream to write (must be at least sizeof(I))
* #param i Integer to write
*/
template< typename I >
static ZT_INLINE void storeLittleEndian(void *const p, const I i) noexcept
{
#if __BYTE_ORDER == __BIG_ENDIAN
storeMachineEndian(p,_swap_bytes_bysize<I,sizeof(I)>::s(i));
#else
#ifdef ZT_NO_UNALIGNED_ACCESS
storeMachineEndian(p,i);
#else
*reinterpret_cast<I *>(p) = i;
#endif
#endif
}
/**
* Copy memory block whose size is known at compile time.
*
* @tparam L Size of memory
* @param dest Destination memory
* @param src Source memory
*/
template< unsigned long L >
static ZT_INLINE void copy(void *dest, const void *src) noexcept
{
#if defined(ZT_ARCH_X64) && defined(__GNUC__)
uintptr_t l = L;
__asm__ __volatile__ ("cld ; rep movsb" : "+c"(l), "+S"(src), "+D"(dest) :: "memory");
#else
memcpy(dest, src, L);
#endif
}
/**
* Copy memory block whose size is known at run time
*
* @param dest Destination memory
* @param src Source memory
* @param len Bytes to copy
*/
static ZT_INLINE void copy(void *dest, const void *src, unsigned long len) noexcept
{
#if defined(ZT_ARCH_X64) && defined(__GNUC__)
__asm__ __volatile__ ("cld ; rep movsb" : "+c"(len), "+S"(src), "+D"(dest) :: "memory");
#else
memcpy(dest, src, len);
#endif
}
/**
* Zero memory block whose size is known at compile time
*
* @tparam L Size in bytes
* @param dest Memory to zero
*/
template< unsigned long L >
static ZT_INLINE void zero(void *dest) noexcept
{
#if defined(ZT_ARCH_X64) && defined(__GNUC__)
uintptr_t l = L;
__asm__ __volatile__ ("cld ; rep stosb" :"+c" (l), "+D" (dest) : "a" (0) : "memory");
#else
memset(dest, 0, L);
#endif
}
/**
* Zero memory block whose size is known at run time
*
* @param dest Memory to zero
* @param len Size in bytes
*/
static ZT_INLINE void zero(void *dest, unsigned long len) noexcept
{
#if defined(ZT_ARCH_X64) && defined(__GNUC__)
__asm__ __volatile__ ("cld ; rep stosb" :"+c" (len), "+D" (dest) : "a" (0) : "memory");
#else
memset(dest, 0, len);
#endif
}
/**
* Hexadecimal characters 0-f
*/
static const char HEXCHARS[16];
/*
* Remove `-` and `:` from a MAC address (in-place).
*
* @param mac The MAC address
*/
static inline void cleanMac(std::string& mac)
{
auto start = mac.begin();
auto end = mac.end();
auto new_end = std::remove_if(start, end, [](char c) { return c == 45 || c == 58; });
mac.erase(new_end, end);
}
};
} // namespace ZeroTier
#endif