Ez ê bê navber dest pê bikim, gava ku min eşkere kir (baş, ne pir bi hêz, bi rastî) û fikir derket ku ez bernameyek çap bikim ku wêneyek ji xerîdar vediguheze serverek. bes sade rast? Welê, ji bo bernamenûsek bi ezmûn, ew ê wusa be. Şert hêsan in - pirtûkxaneyên sêyemîn bikar neynin. Di prensîbê de, ew hinekî tevlihevtir e, lê ji ber ku hûn neçar in ku wê fêhm bikin û li mînakan bigerin, baş e, karekî weha. Min biryar da ku ev kar li ser min e. Zêdeyî, tê xwestin ku kod têra xwe hebe da ku heke hewcedariya we bi alîkariyê hebe ew li ser forumê were şandin. Berî her tiştî, çavên min li FTP-ê ket, bi awayê, OS-ya ku Windows tê de tête pêşve xistin. Feydeya FTP ev e ku hûn ne tenê wêneyek, lê her pelek bi wê veguhezînin. Piştî dakêşana Servera Filezilla, parvekirina yek pelrêça ji bo xwendin / nivîsandin û afirandina bikarhênerek bi şîfreyek, min hewl da ku Filezilla Client ve girêbide, her tişt xebitî. Min di C/C++ de mînakek kodek hêsan çêkir:
#include <iostream>
void main()
{
FILE* fs;
fopen_s(&fs, "1.txt", "w");
if (fs)
{
fwrite("userrnpasswordrnsend D:\share\1.txtrnbye", 1, sizeof("userrnpasswordrnsend D:\share\1.txtrnbye"), fs);
fwrite(" 00", 1, sizeof(" 00"), fs);
fclose(fs);
}
system("ftp -s:1.txt 127.0.0.1");
}Ger bîranîna min ji min re xizmet dike, wê hingê her tişt li ser hosteya herêmî xebitî, û dema ku li ser torê veguhezîne, di rêza şandinê de xeletiyek derket. Ya ku li vir hêsan e a) bi kurtî b) hûn ne hewce ne ku xerîdarek saz bikin, lê ji bo ftp-ê ji Microsoft-ê amûra ku berê hatî çêkirin bikar bînin. Her çend li gorî min divê bi bername û pêkhateyan were aktîfkirin. Ger hûn fêm bikin ka pirsgirêka vê rêbazê çi ye û di şîroveyan de binivîsin, ew ê pir baş be.
Ji ber ku min di gelek foruman de bersivek nedît, min ev kod terikand û biryar da ku navrûyek tora soketan bikar bînim. Min berê ezmûna veguheztina rêzek karakteran bo bernameyek din hebû. Bi awayê, hûn dikarin beşa "Tora Komputerê" ya Tanenbaum li ser qata veguhastinê bixwînin. Nimûneyek xerîdar û serverek heye, her çend ne ji bo girêdana "gelek xerîdar bi yek serverê re", lê tenê ji bo "yek xerîdar bi yek serverê re". Ji ber ku veguhastin li ser înternetê ye, pêdivî ye ku daneyên bi rengekî werin şîfrekirin. Şîfreyek blok - toreke Feistel - ji bo vê yekê tê bikar anîn. Avantajek ji bo server Pêdivî ye ku em gelek xerîdaran (ji yekê zêdetir) biafirînin. Ji bo vê yekê, em ê Threads bikar bînin. Wêneya ku were veguheztin dê dîmenek ji xerîdar be, şîfrekirî be, û ji serverê re were şandin, li wir ew ê were şîfrekirin û tavilê bi karanîna bernameya xwerû ji bo vekirina wêneyên *.tga were nîşandan.
Koda serverê:
#include <iostream>
#include <WinSock.h>
#pragma comment (lib,"WS2_32.lib")
#include <fstream>
#include <algorithm>
#include <string>
#include <iterator>
#include <vector>
void error(const char* msg)
{
//perror(msg);
std::cout<<'n'<<WSAGetLastError();
WSACleanup();
std::cin.ignore();
exit(1);
}
void bzero(char*buf, int l)
{
for (int i = 0; i < l; i++)
buf[i] = ' ';
}
struct arg_s
{
unsigned char* buffer2;
bool exit;
};
char** buffer;
struct arg_sa
{
struct arg_s* lalk;
int current;
};
#define type struct arg_sa
int sockfd, * newsockfd;//слушающий и массив клиентских сокетов
int buflen2 = 10292000;//максимальный размер изображения в байтах для RGBA*Width*Height
struct sockaddr_in *cli_addr;
int* clilen;
int currentclient,cc;//сс-клиент по счету(для записи инкремента имени файла клиента изображения)
typedef unsigned long long uint64_t;
typedef unsigned int uint32_t;
#define N 8//размер блока
#define F32 0xFFFFFFFF
uint32_t RK[N];//раундовые ключи
#define size64 sizeof(uint64_t)
#define ROR(x,n,xsize)((x>>n)|(x<<(xsize-n)))
#define ROL(x,n,xsize)((x<<n)|(x>>(xsize-n)))
#define RKEY(r)((ROR(K,r*3,size64*8))&F32)
const uint64_t K = 0x96EA704CFB1CF671;//ключ шифрования
struct hostent* server;
uint32_t F(uint32_t subblk, uint32_t key)
{
return subblk + key;//функция шифрования
}
void createRoundKeys()
{
for (int i = 0; i < N; i++)
RK[i] = (ROR(K, i * 8, size64 * 8)) & F32;
}
uint64_t decrypt(uint64_t c_block)//расшифровка блоков сетью фейстеля
{
//select subblocks
uint32_t left = (c_block >> 32) & F32;
uint32_t right = c_block & F32;
uint32_t left_, right_;//subblock in the end of round
for (int r = N - 1; r >= 0; r--)
{
uint32_t fk = F(left, RK[r]);
left_ = left;
right_ = right ^ fk;
if (r > 0)//swap places to next round
{
left = right_;
right = left_;
}
else //last round not swap
{
left = left_;
right = right_;
}
}
//collect subblock in block
uint64_t block = left;
block = (block << 32) | (right & F32);
return block;
}
void session_(LPVOID args)//функция потока ля каждого клиента
{
int current = currentclient++;
bzero((char*)&(cli_addr[current]), sizeof(&(cli_addr[current])));
newsockfd[current] = accept(sockfd, (struct sockaddr*)&(cli_addr[current]), &(clilen[current]));
if (newsockfd[current] < 0)
{
error("Error on acceptn");
}
char* s = new char[100];
int n = recv(newsockfd[current], s, 100, 0);
int buflen2 = atoi(s);//получаем число байтов изображения
FILE* f;
std::string name = "Screen";
cc++;
_itoa_s(cc, s, 100, 10);
name += s;
name += ".tga";
fopen_s(&f,name.c_str(), "wb");//создаем файл изображения с увеличиваещимся на 1 именем, чтобы не перезаписать
if (f != NULL)
{
unsigned char tgaHeader[12] = { 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
unsigned char header[6];
n = recv(newsockfd[current], buffer[current], sizeof(tgaHeader), 0);
fwrite((unsigned char*)buffer[current], 1, sizeof(tgaHeader), f);
bzero(buffer[current], buflen2);
n = recv(newsockfd[current], buffer[current],sizeof(header), 0);
fwrite((unsigned char*)buffer[current], 1, sizeof(header), f);//записали хидеры
bzero(buffer[current], buflen2);
n = recv(newsockfd[current], buffer[current], buflen2, 0);//получили байты самого изображения
//
//расшифровка байтов
createRoundKeys();
unsigned long long id;
std::vector<uint64_t>* plaintext = new std::vector<uint64_t>();
int i = 0;
while (i<buflen2)
{
memcpy(&id, (buffer[current]) + i, N);
plaintext->push_back(decrypt(id));
i += 8;
}
std::cout << "i=" << i << std::endl;
i = 0;
char str_[N + 1];
memset(str_, 0, N);
str_[N] = ' ';
for (std::vector<uint64_t>::iterator it = plaintext->begin(); it != plaintext->end(); ++it)
{
memcpy(str_, &*it, N);
fwrite((unsigned char*)str_, sizeof(unsigned char), N/*strlen(str_)*/, f);
i += 8;
}
std::cout << "i=" << i << std::endl;
//конец рашифровки байтов
//fwrite((unsigned char*)buffer[current], sizeof(char), buflen2, f);
fclose(f);
}
system(name.c_str());//открываем изображение *.tga встроенным редактором
}
int main()
{
cc = 0;
WSADATA ws = { 0 };
if (WSAStartup(MAKEWORD(2, 2), &ws) == 0)
{
currentclient = 0;
int maxclients = 2;//максимальное число клиентов
cli_addr = new struct sockaddr_in[maxclients];
clilen = new int[maxclients];
buffer = new char* [maxclients];
for (int i = 0; i < maxclients; i++)
{
clilen[i] = sizeof(cli_addr[i]);
}
sockfd = socket(AF_INET, SOCK_STREAM, 0);//tcp сокет
if (sockfd < 0)
error("ERROR opening socket");
struct sockaddr_in serv_addr;
bzero((char*)&serv_addr, sizeof(serv_addr));
serv_addr.sin_family = AF_INET;
serv_addr.sin_addr.s_addr = INADDR_ANY;
int port = 30000;//порт
serv_addr.sin_port = htons(port);
if (bind(sockfd, (struct sockaddr*)&serv_addr, sizeof(serv_addr)) < 0)
error("ERROR on binding");
if (listen(sockfd, 10) < 0)
error("ERROR listen");
HANDLE* thread;//массив потоков для каждого клиента отдельный
struct arg_sa* args;
while (true)
{
newsockfd = new int[maxclients];
thread = (HANDLE*)malloc(sizeof(HANDLE) * maxclients);
args = new struct arg_sa[maxclients];
for (int i = 0; i < maxclients; i++)
{
args[i].lalk = new struct arg_s();
buffer[i] = new char[buflen2];
}
int i = -1;
while (++i < maxclients)
{
Sleep(1);
args[i].current = i;
args[i].lalk->exit = false;
thread[i] = CreateThread(0, 0, (LPTHREAD_START_ROUTINE)(session_), args, 0, 0);
}
for (int i = 0; i < maxclients; i++)
WaitForSingleObject(thread[i], INFINITE);//ждем завершения всех потоков
i = -1;
while (++i < maxclients)
{
shutdown(newsockfd[i], 0);
TerminateThread(thread[i], 0);
}
//delete[] newsockfd;
//free(thread);
currentclient = 0;
for (int i = 0; i < maxclients; i++)
{
//delete args[i].lalk;
//delete[] args[i].lalk->buffer;
}
//delete[] args;
}
shutdown(sockfd, 0);
WSACleanup();
return 0;
}
std::cin.ignore();
}Bi kurtasî, di çerxeke bêdawî de, têl ji bo her xerîdar têne afirandin û li benda girêdana xerîdaran in. Piştre, WaitForSingleObject li benda wan e ku her tiştî veguhezînin. Her xerîdarek soket û bafera xwe ya veguheztinê heye. Ango, server Soketa M+1, ku M hejmara xerîdaran e. Piştî ku hemû veguhastin qediyan, her tişt dubare dibe.
Niha xerîdar bifikirin:
#include <iostream>
#include <WinSock.h>
#include <vector>
#pragma comment (lib,"WS2_32.lib")
void error(const char* msg)
{
//perror(msg);
std::cout << 'n' << WSAGetLastError();
WSACleanup();
std::cin.ignore();
exit(1);
}
void bzero(char* buf, int l)
{
for (int i = 0; i < l; i++)
buf[i] = ' ';
}
typedef unsigned long long uint64_t;
typedef unsigned int uint32_t;
#define N 8
#define F32 0xFFFFFFFF
uint32_t RK[N];//раундовые ключи
#define size64 sizeof(uint64_t)
#define ROR(x,n,xsize)((x>>n)|(x<<(xsize-n)))
#define ROL(x,n,xsize)((x<<n)|(x>>(xsize-n)))
#define RKEY(r)((ROR(K,r*3,size64*8))&F32)
const uint64_t K = 0x96EA704CFB1CF671;//ключ шифрования
void createRoundKeys()
{
for (int i = 0; i < N; i++)
RK[i] = (ROR(K, i * 8, size64 * 8)) & F32;
}
uint32_t F(uint32_t subblk, uint32_t key)
{
return subblk + key;//функция шифрования
}
uint64_t encrypt(uint64_t block)//зашифровка блоков сетью Фейстеля
{
//select subblocks
uint32_t left = (block >> 32) & F32;
uint32_t right = block & F32;
uint32_t left_, right_;//subblock in the end of round
for (int r = 0; r < N; r++)
{
uint32_t fk = F(left, RK[r]);
left_ = left;
right_ = right ^ fk;
if (r < N - 1)//swap places to next round
{
left = right_;
right = left_;
}
else//last round not swap
{
left = left_;
right = right_;
}
}
//collect subblock in block
uint64_t c_block = left;
c_block = (c_block << 32) | (right & F32);
return c_block;
}
int main()
{
keybd_event(VK_LWIN, 0, 0, 0);
keybd_event('M', 0, 0, 0);
keybd_event('M', 0, KEYEVENTF_KEYUP, 0);
keybd_event(VK_LWIN, 0, KEYEVENTF_KEYUP, 0);//эти строки сворачивают все приложения
Sleep(1000);//чтобы сделать скриншот рабочего стола
WSADATA ws = { 0 };
if (WSAStartup(MAKEWORD(2, 2), &ws) == 0)
{
int sockfd;
sockfd = socket(AF_INET, SOCK_STREAM, 0);
struct sockaddr_in serv_addr, cli_addr;
bzero((char*)&serv_addr, sizeof(serv_addr));
bzero((char*)&cli_addr, sizeof(cli_addr));
serv_addr.sin_family = AF_INET;
const char* add = "127.0.0.1";//адрес сервера
serv_addr.sin_addr.s_addr = inet_addr(add);
int port = 30000;//порт
serv_addr.sin_port = htons(port);
int servlen = sizeof(serv_addr);
int n = connect(sockfd, (struct sockaddr*)&serv_addr, servlen);
//ниже код делает скриншот
HDC ScreenDC = GetDC(0);
HDC MemoryDC = CreateCompatibleDC(ScreenDC);
int ScreenHeight = GetSystemMetrics(SM_CYSCREEN);
int ScreenWidth = GetSystemMetrics(SM_CXSCREEN);
ScreenWidth = ((ScreenWidth - 1) / 4 + 1) * 4;
BITMAPINFO BMI;
BMI.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
BMI.bmiHeader.biWidth = ScreenWidth;
BMI.bmiHeader.biHeight = ScreenHeight;
BMI.bmiHeader.biSizeImage = ScreenWidth * ScreenHeight * 3;
BMI.bmiHeader.biCompression = BI_RGB;
BMI.bmiHeader.biBitCount = 24;
BMI.bmiHeader.biPlanes = 1;
DWORD ScreenshotSize;
ScreenshotSize = BMI.bmiHeader.biSizeImage;
unsigned char* ImageBuffer;
HBITMAP hBitmap = CreateDIBSection(ScreenDC, &BMI, DIB_RGB_COLORS, (void**)&ImageBuffer, 0, 0);
SelectObject(MemoryDC, hBitmap);
BitBlt(MemoryDC, 0, 0, ScreenWidth, ScreenHeight, ScreenDC, 0, 0, SRCCOPY);
DeleteDC(MemoryDC);
ReleaseDC(NULL, ScreenDC);
FILE* sFile = 0;
unsigned char tgaHeader[12] = { 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
unsigned char header[6];
unsigned char tempColors = 0;
fopen_s(&sFile, "S.tga", "wb");
if (!sFile) {
exit(1);
}
header[0] = ScreenWidth % 256;
header[1] = ScreenWidth / 256;
header[2] = ScreenHeight % 256;
header[3] = ScreenHeight / 256;
header[4] = BMI.bmiHeader.biBitCount;
header[5] = 0;
fwrite(tgaHeader, 1, sizeof(tgaHeader), sFile);
fwrite(header, sizeof(header), 1, sFile);
//конец записали изображение в файл
//шифруем блоками полезную нагрузку изображения кроме хидеров
createRoundKeys();
std::vector<uint64_t>* msg = new std::vector<uint64_t>(),*crpt = new std::vector<uint64_t>();
unsigned long long id;
int i = 0;
while (i < BMI.bmiHeader.biSizeImage)
{
memcpy(&id, (ImageBuffer + i), N);
msg->push_back(id);
i += 8;
}
std::cout << "i=" << i << std::endl;
uint64_t cipher;
i = 0;
char str_[N + 1];
memset(str_, 0, N);
str_[N] = ' ';
for (std::vector<uint64_t>::iterator it = msg->begin(); it != msg->end(); ++it)
{
cipher = encrypt(*it);
memcpy(str_, &cipher, N);
fwrite((unsigned char*)str_, sizeof(unsigned char), N, sFile);
i += 8;
}
std::cout << "i=" << i << std::endl;
//
//fwrite(ImageBuffer, BMI.bmiHeader.biSizeImage, 1, sFile);
std::cout << BMI.bmiHeader.biSizeImage << std::endl;
fclose(sFile);
DeleteObject(hBitmap);
FILE* f;
fopen_s(&f, "S.tga", "rb");
int count = 0;
if (f != NULL)
{
while (getc(f) != EOF)
count++;//считаем байты изображения в счетчик чтобы потом передать
fclose(f);
}
count -= 18;
std::cout << count<< std::endl;
char* s = new char[100];
_itoa_s(count, s, 100, 10);
n = send(sockfd, s, 100, 0);//передаем счетчик
char* buffer = new char[count];
fopen_s(&f, "S.tga", "rb");
size_t bytes;
if (f != NULL)
{
memcpy(buffer, tgaHeader, sizeof(tgaHeader));
n = send(sockfd, buffer, sizeof(tgaHeader), 0);
bzero(buffer, count);
memcpy(buffer, header, sizeof(header));
n = send(sockfd, buffer, sizeof(header), 0);
bzero(buffer, count);//передаем хидеры
for(int i=0;i<18;i++)
fgetc(f);
bzero(buffer, count);
bytes = fread(buffer, sizeof(unsigned char), count, f);
n = send(sockfd,buffer, count, 0);//передаем шифрованные байты изображения
fclose(f);
}
Sleep(1000);
shutdown(sockfd, 0);
WSACleanup();
//system("del S.tga");
delete[] buffer,s;
return 0;
}
//std::cin.ignore();
}Li vir encama xebata xerîdar, pelê dîmendera S.tga, şîfrekirî ye
Wusa dixuye ku ew sermaseyek e.
Û li vir encamek e ku ji hêla Screen.tga ve ji serverê re hate veguheztin û deşîfre kirin
Wekî ku hûn dibînin, tora Feistel-a normal ji bo şîfrekirinê ne maqûl e, lê hûn dikarin rêbazên CBC û CFB bikar bînin, dibe ku ew ê çêtir were şîfrekirin, bi rastî, min ew kontrol nekir.
Ji bo baldariya te spas!
Source: www.habr.com
