Wieso stimmen die string überein, obwohl sie's doch net tuen?

[Takt]

Also egal welche port:pw kombi ich übergebe, die Daten stimmen angeblich immer :-/
Der Fehler muss in compairKey() liegen welches immer 0 zurück gibt, was es nicht soll...
kann mir da jemand helfen?

Hier der Code:


/***********************************************
*** This is the Port knocking Daemon by Takt ***
*** (C) 2004 by Oliver Herms ***
*** takt@excluded.org ***
***********************************************/

#include <stdio.h>
#include <iostream>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/signal.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <fstream>

using namespace std;

int compairKey(char *Key)
{
char buffer[4096];
ifstream fin("/etc/portknock.conf");
while(!fin.eof())
{
memset(buffer, 0x00, sizeof(buffer));
fin >> buffer;
cout << buffer << endl;
if(!strncmp(buffer, Key, sizeof(Key)))
{
return 0;
}
}
return -1;
}


int main()
{
int sockfd, connfd, port;
char buffer[2048];
char buffer2[2048];
char ipt[255];
socklen_t len;
pid_t pid;
struct sockaddr_in servaddr, cliaddr;

servaddr.sin_family = AF_INET;
servaddr.sin_port = htons(33333);
servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if(sockfd < 0)
{
cout << "Sorry, couldn't create socket, no describtors left?\n";
return -1;
}
if(bind(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr)) < 0)
{
cout << "Sorry, couldn't bind port, could be in use!?\n";
return -1;
}
listen(sockfd, 10);
len = sizeof(cliaddr);

while(1)
{
connfd = accept(sockfd, (struct sockaddr *)&cliaddr,&len);
if( (pid = fork()) == 0) /* ****EN */
{
close(sockfd);
memset(buffer, 0x00, sizeof(buffer));
snprintf(buffer, sizeof(buffer), "Welcome to port knock...\n");
write(connfd, buffer, strlen(buffer));
memset(buffer, 0x00, sizeof(buffer));
read(connfd, buffer, sizeof(buffer));
port = atoi(buffer);
if(port<1 || port>65535)
{
memset(buffer, 0x00, strlen(buffer));
snprintf(buffer, sizeof(buffer), "%d is not a valid port...\n", port);
write(connfd, buffer, sizeof(buffer));
}
else
{
snprintf(buffer, sizeof(buffer), "Please send your KEY now!\n");
write(connfd, buffer, sizeof(buffer));
memset(buffer, 0x00, sizeof(buffer));
read(connfd, buffer, sizeof(buffer));
snprintf(buffer2, sizeof(buffer2), "%d:%s\n", port, buffer);
cout << buffer2 << endl;
if(compairKey(buffer2) == 0)
{
cout << "compairKey returned 0\n";
snprintf(ipt, sizeof(ipt), "iptables -A INPUT -p tcp --dport %d -s %s -j ACCEPT", port, inet_ntoa(cliaddr.sin_addr));
system(ipt);
memset(buffer, 0x00, sizeof(buffer));
snprintf(buffer, sizeof(buffer), "Key OK, opening port...\n");
write(connfd, buffer, sizeof(buffer));
}
else
{
memset(buffer, 0x00, sizeof(buffer));
snprintf(buffer, sizeof(buffer), "Sorry, key doesnt match... bye...\n");
write(connfd, buffer, sizeof(buffer));
}
}
exit(0);
}
}
close(sockfd);
}

MfG. Takt

[anda_skoa]

sizeof(char*) dürfte bei dir 4 sein, d.h. wahrscheinlich waren die erszen 4 byte immer gleich.

Vermutlich wolltest du den übergebenen String mit dem Anfang einer gelesenen Zeile vergleichen.

Das hätte ich so gemacht



bool compairKey(const std::string& key)
{
std::string line;
ifstream fin("/etc/portknock.conf");
while(!fin.eof())
{
getline(fin, line);
cout << line << endl;
if(line.find(key) == 0))
{
return true;
}
}

return false;
}


Ciao,
_