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#include <stdlib.h> /* for exit(), getenv() */
#include <iostream>
#include <string>
#include <sys/types.h> /* for stat() */
#include <sys/stat.h> /* for stat() */
#include <unistd.h> /* for stat() */
#include <stdio.h> /* for perror */
#include <errno.h> /* for ENOENT */
#include <fstream> /* for ofstream() */
#include <fcntl.h> /* for creat() */
#include <sys/time.h> /* for gettimeofday() */
using namespace std;
const int sa_good = 0;
const int bug_bait_grey = 1;
// qmail_queue and spamc have similar interpretations here:
const int sa_syserr = 71;
pid_t mypid;
string progname;
void dump(const string var){
char* str = getenv(var.c_str());
cerr << progname
<< "[" << mypid << "] "
<< var;
if (str) cerr << " is set to '" << str << "'" << endl;
else cerr << " is not set." << endl;
}
const string dirname("/var/qmail/greylist");
// int stat(const char *path, struct stat *buf);
// int fstat(int fd, struct stat *buf);
// int lstat(const char *path, struct stat *buf);
const int minute(60);
const int hour(60*minute);
const int day(24*hour);
class whatsit{
public:
string progname;
pid_t mypid;
timeval now;
string ipname;
int mod_age;
int ac_age;
whatsit(const string name)
: progname(name), mypid(getpid())
{
gettimeofday(&now, NULL);
}
int doit();
// access comes after modification:
void update(const string msg, const timeval new_mod, const timeval new_ac);
};
void whatsit::update(const string msg, const timeval new_mod, const timeval new_ac){
cerr << progname << ": "
<< msg << ": " << ipname
<< " mod_age: " << mod_age
<< " ac_age: " << ac_age
<< endl;
timeval upd[2] = {
// beware: access illogically comes *before* modification here:
new_ac,
new_mod
};
utimes(ipname.c_str(), upd);
}
int main(int argc, char** argv){
// dump("TCPREMOTEIP");
// dump("TCPREMOTEHOST");
whatsit foo(argv[0]);
return foo.doit();
}
int whatsit::doit(){
char* ipvar = getenv("TCPREMOTEIP");
if (!ipvar) {
cerr << progname << ": TCPREMOTEIP not set???" << endl;
exit(sa_syserr);
}
string ipbase = ipvar;
// see if our directory exists:
struct stat dirstat;
int rslt = stat(dirname.c_str(), &dirstat);
if (rslt != 0){
if (errno != ENOENT) {
cerr << progname << ": stat failed for '"
<< dirname << "' : ";
perror(0);
}
rslt = mkdir(dirname.c_str(), 0755);
if (rslt != 0) {
cerr << progname
<< "uid " << getuid()
<< ": mkdir failed for '"
<< dirname << "' : ";
perror(0);
exit(sa_syserr);
}
}
ipname = dirname + "/" + ipbase;
struct stat ipstat;
rslt = stat(ipname.c_str(), &ipstat);
if (rslt != 0){
if (errno != ENOENT) {
cerr << progname << ": stat failed for '"
<< ipname << "' : ";
perror(0);
}
ofstream foo;
int fd = creat(ipname.c_str(), 0644);
if (fd < 0){
cerr << progname << ": create failed for '"
<< ipname << "' : ";
perror(0);
}
close(fd);
update("new customer", now, now);
return(bug_bait_grey);
}
// here if stat succeeded
mod_age = now.tv_sec - ipstat.st_mtime;
ac_age = now.tv_sec - ipstat.st_atime;
timeval mod_orig = {ipstat.st_mtime, 0};
if (mod_age < 5*minute) {
update("early bird", mod_orig, now);
return(bug_bait_grey);
}
if (ac_age < 32*day) {
update("returning customer", mod_orig, now);
return 0;
}
// here if it is too old:
update("too old, starting over", now, now);
return(bug_bait_grey);
}
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