ZeroTierOne/node/Utils.hpp

555 lines
16 KiB
C++

/*
* ZeroTier One - Global Peer to Peer Ethernet
* Copyright (C) 2012-2013 ZeroTier Networks LLC
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* --
*
* ZeroTier may be used and distributed under the terms of the GPLv3, which
* are available at: http://www.gnu.org/licenses/gpl-3.0.html
*
* If you would like to embed ZeroTier into a commercial application or
* redistribute it in a modified binary form, please contact ZeroTier Networks
* LLC. Start here: http://www.zerotier.com/
*/
#ifndef _ZT_UTILS_HPP
#define _ZT_UTILS_HPP
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <time.h>
#include <sys/time.h>
#include <arpa/inet.h>
#include <string>
#include <stdexcept>
#include <vector>
#include "../ext/lz4/lz4.h"
#include "../ext/lz4/lz4hc.h"
#include "../ext/huffandpuff/huffman.h"
#include "Constants.hpp"
/**
* Maximum compression/decompression block size (do not change)
*/
#define ZT_COMPRESSION_BLOCK_SIZE 16777216
namespace ZeroTier {
/**
* Miscellaneous utility functions and global constants
*/
class Utils
{
public:
/**
* @param data Data to convert to hex
* @param len Length of data
* @return Hexadecimal string
*/
static std::string hex(const void *data,unsigned int len);
static inline std::string hex(const std::string &data) { return hex(data.data(),data.length()); }
/**
* @param hex Hexadecimal ASCII code (non-hex chars are ignored)
* @return Binary data
*/
static std::string unhex(const char *hex);
static inline std::string unhex(const std::string &hex) { return unhex(hex.c_str()); }
/**
* @param hex Hexadecimal ASCII
* @param buf Buffer to fill
* @param len Length of buffer
* @return Number of characters actually written
*/
static unsigned int unhex(const char *hex,void *buf,unsigned int len);
/**
* @param buf Buffer to fill
* @param bytes Number of random bytes to generate
*/
static void getSecureRandom(void *buf,unsigned int bytes);
/**
* Set modes on a file to something secure
*
* This locks a file so that only the owner can access it. What it actually
* does varies by platform.
*
* @param path Path to lock
* @param isDir True if this is a directory
*/
static void lockDownFile(const char *path,bool isDir);
/**
* Get file last modification time
*
* Resolution is often only second, not millisecond, but the return is
* always in ms for comparison against now().
*
* @param path Path to file to get time
* @return Last modification time in ms since epoch or 0 if not found
*/
static uint64_t getLastModified(const char *path);
/**
* @param t64 Time in ms since epoch
* @return RFC1123 date string
*/
static std::string toRfc1123(uint64_t t64);
/**
* @param tstr Time in RFC1123 string format
* @return Time in ms since epoch
*/
static uint64_t fromRfc1123(const char *tstr);
static inline uint64_t fromRfc1123(const std::string &tstr) { return fromRfc1123(tstr.c_str()); }
/**
* String append output function object for use with compress/decompress
*/
class StringAppendOutput
{
public:
StringAppendOutput(std::string &s) : _s(s) {}
inline void operator()(const void *data,unsigned int len) { _s.append((const char *)data,len); }
private:
std::string &_s;
};
/**
* STDIO FILE append output function object for compress/decompress
*
* Throws std::runtime_error on write error.
*/
class FILEAppendOutput
{
public:
FILEAppendOutput(FILE *f) : _f(f) {}
inline void operator()(const void *data,unsigned int len)
throw(std::runtime_error)
{
if ((int)fwrite(data,1,len,_f) != (int)len)
throw std::runtime_error("write failed");
}
private:
FILE *_f;
};
/**
* Compress data
*
* O must be a function or function object that takes the following
* arguments: (const void *data,unsigned int len)
*
* @param in Input iterator that reads bytes (char, uint8_t, etc.)
* @param out Output iterator that writes bytes
*/
template<typename I,typename O>
static inline void compress(I begin,I end,O out)
{
char huffheap[HUFFHEAP_SIZE];
unsigned int bufLen = LZ4_compressBound(ZT_COMPRESSION_BLOCK_SIZE);
char *buf = new char[bufLen * 2];
char *buf2 = buf + bufLen;
try {
I inp(begin);
for(;;) {
unsigned int readLen = 0;
while ((readLen < ZT_COMPRESSION_BLOCK_SIZE)&&(inp != end)) {
buf[readLen++] = (char)*inp;
++inp;
}
if (!readLen)
break;
uint32_t l = hton((uint32_t)readLen);
out((const void *)&l,4); // original size
if (readLen < 32) { // don't bother compressing itty bitty blocks
l = 0; // stored
out((const void *)&l,4);
out((const void *)buf,readLen);
continue;
}
int lz4CompressedLen = LZ4_compressHC(buf,buf2,(int)readLen);
if ((lz4CompressedLen <= 0)||(lz4CompressedLen >= (int)readLen)) {
l = 0; // stored
out((const void *)&l,4);
out((const void *)buf,readLen);
continue;
}
unsigned long huffCompressedLen = huffman_compress((const unsigned char *)buf2,lz4CompressedLen,(unsigned char *)buf,bufLen,huffheap);
if ((!huffCompressedLen)||((int)huffCompressedLen >= lz4CompressedLen)) {
l = hton((uint32_t)lz4CompressedLen); // lz4 only
out((const void *)&l,4);
out((const void *)buf2,(unsigned int)lz4CompressedLen);
} else {
l = hton((uint32_t)0x80000000 | (uint32_t)huffCompressedLen); // lz4 with huffman
out((const void *)&l,4);
out((const void *)buf,(unsigned int)huffCompressedLen);
}
}
delete [] buf;
} catch ( ... ) {
delete [] buf;
throw;
}
}
/**
* Decompress data
*
* O must be a function or function object that takes the following
* arguments: (const void *data,unsigned int len)
*
* @param in Input iterator that reads bytes (char, uint8_t, etc.)
* @param out Output iterator that writes bytes
* @return False on decompression error
*/
template<typename I,typename O>
static inline bool decompress(I begin,I end,O out)
{
char huffheap[HUFFHEAP_SIZE];
volatile char i32c[4];
void *const i32cp = (void *)i32c;
unsigned int bufLen = LZ4_compressBound(ZT_COMPRESSION_BLOCK_SIZE);
char *buf = new char[bufLen * 2];
char *buf2 = buf + bufLen;
try {
I inp(begin);
while (inp != end) {
i32c[0] = (char)*inp; if (++inp == end) { delete [] buf; return false; }
i32c[1] = (char)*inp; if (++inp == end) { delete [] buf; return false; }
i32c[2] = (char)*inp; if (++inp == end) { delete [] buf; return false; }
i32c[3] = (char)*inp; if (++inp == end) { delete [] buf; return false; }
unsigned int originalSize = ntoh(*((const uint32_t *)i32cp));
i32c[0] = (char)*inp; if (++inp == end) { delete [] buf; return false; }
i32c[1] = (char)*inp; if (++inp == end) { delete [] buf; return false; }
i32c[2] = (char)*inp; if (++inp == end) { delete [] buf; return false; }
i32c[3] = (char)*inp; if (++inp == end) { delete [] buf; return false; }
uint32_t _compressedSize = ntoh(*((const uint32_t *)i32cp));
unsigned int compressedSize = _compressedSize & 0x7fffffff;
if (compressedSize) {
if (compressedSize > bufLen) {
delete [] buf;
return false;
}
unsigned int readLen = 0;
while ((readLen < compressedSize)&&(inp != end)) {
buf[readLen++] = (char)*inp;
++inp;
}
if (readLen != compressedSize) {
delete [] buf;
return false;
}
if ((_compressedSize & 0x80000000)) { // lz4 and huffman
unsigned long lz4CompressedSize = huffman_decompress((const unsigned char *)buf,compressedSize,(unsigned char *)buf2,bufLen,huffheap);
if (lz4CompressedSize) {
if (LZ4_uncompress_unknownOutputSize(buf2,buf,lz4CompressedSize,bufLen) != (int)originalSize) {
delete [] buf;
return false;
} else out((const void *)buf,(unsigned int)originalSize);
} else {
delete [] buf;
return false;
}
} else { // lz4 only
if (LZ4_uncompress_unknownOutputSize(buf,buf2,compressedSize,bufLen) != (int)originalSize) {
delete [] buf;
return false;
} else out((const void *)buf2,(unsigned int)originalSize);
}
} else { // stored
if (originalSize > bufLen) {
delete [] buf;
return false;
}
unsigned int readLen = 0;
while ((readLen < originalSize)&&(inp != end)) {
buf[readLen++] = (char)*inp;
++inp;
}
if (readLen != originalSize) {
delete [] buf;
return false;
}
out((const void *)buf,(unsigned int)originalSize);
}
}
delete [] buf;
return true;
} catch ( ... ) {
delete [] buf;
throw;
}
}
/**
* @return Current time in milliseconds since epoch
*/
static inline uint64_t now()
throw()
{
struct timeval tv;
gettimeofday(&tv,(struct timezone *)0);
return ( (1000ULL * (uint64_t)tv.tv_sec) + (uint64_t)(tv.tv_usec / 1000) );
};
/**
* Read the full contents of a file into a string buffer
*
* The buffer isn't cleared, so if it already contains data the file's data will
* be appended.
*
* @param path Path of file to read
* @param buf Buffer to fill
* @return True if open and read successful
*/
static bool readFile(const char *path,std::string &buf);
/**
* Write a block of data to disk, replacing any current file contents
*
* @param path Path to write
* @param buf Buffer containing data
* @param len Length of buffer
* @return True if entire file was successfully written
*/
static bool writeFile(const char *path,const void *buf,unsigned int len);
/**
* Write a block of data to disk, replacing any current file contents
*
* @param path Path to write
* @param s Data to write
* @return True if entire file was successfully written
*/
static inline bool writeFile(const char *path,const std::string &s)
{
return writeFile(path,s.data(),s.length());
}
/**
* @param data Binary data to encode
* @param len Length of data
* @return Base64-encoded string
*/
static std::string base64Encode(const void *data,unsigned int len);
inline static std::string base64Encode(const std::string &data) { return base64Encode(data.data(),data.length()); }
/**
* @param data Base64-encoded string
* @param len Length of encoded string
* @return Decoded binary date
*/
static std::string base64Decode(const char *data,unsigned int len);
inline static std::string base64Decode(const std::string &data) { return base64Decode(data.data(),data.length()); }
/**
* Split a string by delimiter, with optional escape and quote characters
*
* @param s String to split
* @param sep One or more separators
* @param esc Zero or more escape characters
* @param quot Zero or more quote characters
* @return Vector of tokens
*/
static std::vector<std::string> split(const char *s,const char *const sep,const char *esc,const char *quot);
/**
* Trim whitespace from the start and end of a string
*
* @param s String to trim
* @return Trimmed string
*/
static std::string trim(const std::string &s);
/**
* Like sprintf, but appends to std::string
*
* @param s String to append to
* @param fmt Printf format string
* @param ... Format arguments
* @throws std::bad_alloc Memory allocation failure
* @throws std::length_error Format + args exceeds internal buffer maximum
*/
static void stdsprintf(std::string &s,const char *fmt,...)
throw(std::bad_alloc,std::length_error);
/**
* 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)
throw()
{
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);
}
/**
* 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)
throw()
{
for(unsigned int i=0;i<len;++i) {
if (((const unsigned char *)p)[i])
return false;
}
return true;
}
/**
* Match two strings with bits masked netmask-style
*
* @param a First string
* @param abits Number of bits in first string
* @param b Second string
* @param bbits Number of bits in second string
* @return True if min(abits,bbits) match between a and b
*/
static inline bool matchNetmask(const void *a,unsigned int abits,const void *b,unsigned int bbits)
throw()
{
const unsigned char *aptr = (const unsigned char *)a;
const unsigned char *bptr = (const unsigned char *)b;
while ((abits >= 8)&&(bbits >= 8)) {
if (*aptr++ != *bptr++)
return false;
abits -= 8;
bbits -= 8;
}
unsigned char mask = 0xff << (8 - ((abits > bbits) ? bbits : abits));
return ((*aptr & mask) == (*aptr & mask));
}
/**
* Compute CRC64
*
* @param crc Previous CRC (0 to start)
* @param s String to add to crc
* @param l Length of string in bytes
* @return New CRC
*/
static inline uint64_t crc64(uint64_t crc,const void *s,unsigned int l)
throw()
{
for(unsigned int i=0;i<l;++i)
crc = crc64Table[(uint8_t)crc ^ ((const uint8_t *)s)[i]] ^ (crc >> 8);
return crc;
}
static inline uint8_t hton(uint8_t n) throw() { return n; }
static inline int8_t hton(int8_t n) throw() { return n; }
static inline uint16_t hton(uint16_t n) throw() { return htons(n); }
static inline int16_t hton(int16_t n) throw() { return (int16_t)htons((uint16_t)n); }
static inline uint32_t hton(uint32_t n) throw() { return htonl(n); }
static inline int32_t hton(int32_t n) throw() { return (int32_t)htonl((uint32_t)n); }
static inline uint64_t hton(uint64_t n)
throw()
{
#if __BYTE_ORDER == __LITTLE_ENDIAN
#ifdef __GNUC__
return __builtin_bswap64(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
#else
return n;
#endif
}
static inline int64_t hton(int64_t n) throw() { return (int64_t)hton((uint64_t)n); }
static inline uint8_t ntoh(uint8_t n) throw() { return n; }
static inline int8_t ntoh(int8_t n) throw() { return n; }
static inline uint16_t ntoh(uint16_t n) throw() { return ntohs(n); }
static inline int16_t ntoh(int16_t n) throw() { return (int16_t)ntohs((uint16_t)n); }
static inline uint32_t ntoh(uint32_t n) throw() { return ntohl(n); }
static inline int32_t ntoh(int32_t n) throw() { return (int32_t)ntohl((uint32_t)n); }
static inline uint64_t ntoh(uint64_t n)
throw()
{
#if __BYTE_ORDER == __LITTLE_ENDIAN
#ifdef __GNUC__
return __builtin_bswap64(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
#else
return n;
#endif
}
static inline int64_t ntoh(int64_t n) throw() { return (int64_t)ntoh((uint64_t)n); }
/**
* Hexadecimal characters 0-f
*/
static const char HEXCHARS[16];
private:
static const uint64_t crc64Table[256];
static const char base64EncMap[64];
static const char base64DecMap[128];
};
} // namespace ZeroTier
#endif