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/* $Id$ */
#include "bbs.h"
#include <err.h>
struct {
int uid;
int nFriends, nRejects;
int friend[MAX_FRIEND];
int reject[MAX_REJECT];
} utmp[USHM_SIZE];
#ifdef NOFLOODING
#define MAXWAIT 1024
#define FLUSHTIME (3600*6)
struct {
time_t lasttime;
int count;
} flooding[MAX_USERS];
int nWaits, lastflushtime;
struct {
int uid;
int fd;
int index;
} waitqueue[MAXWAIT];
#endif /* NOFLOODING */
inline int countarray(int *s, int max)
{
int i;
for( i = 0 ; i < max && s[i] ; ++i )
;
return i;
}
int
reverse_friend_stat(int stat)
{
int stat1 = 0;
if (stat & IFH)
stat1 |= HFM;
if (stat & IRH)
stat1 |= HRM;
if (stat & HFM)
stat1 |= IFH;
if (stat & HRM)
stat1 |= IRH;
if (stat & IBH)
stat1 |= IBH;
return stat1;
}
int set_friend_bit(int me, int ui)
{
int hit = 0;
/* 判斷對方是否為我的朋友 ? */
if( intbsearch(utmp[ui].uid, utmp[me].friend, utmp[me].nFriends) )
hit = IFH;
/* 判斷我是否為對方的朋友 ? */
if( intbsearch(utmp[me].uid, utmp[ui].friend, utmp[ui].nFriends) )
hit |= HFM;
/* 判斷對方是否為我的仇人 ? */
if( intbsearch(utmp[ui].uid, utmp[me].reject, utmp[me].nRejects) )
hit |= IRH;
/* 判斷我是否為對方的仇人 ? */
if( intbsearch(utmp[me].uid, utmp[ui].reject, utmp[ui].nRejects) )
hit |= HRM;
return hit;
}
void initdata(int index)
{
utmp[index].nFriends = countarray(utmp[index].friend, MAX_FRIEND);
utmp[index].nRejects = countarray(utmp[index].reject, MAX_REJECT);
if( utmp[index].nFriends > 0 )
qsort(utmp[index].friend, utmp[index].nFriends,
sizeof(int), qsort_intcompar);
if( utmp[index].nRejects > 0 )
qsort(utmp[index].reject, utmp[index].nRejects,
sizeof(int), qsort_intcompar);
}
inline void syncutmp(int cfd)
{
int nSynced = 0, i;
for( i = 0 ; i < USHM_SIZE ; ++i, ++nSynced )
if( toread(cfd, &utmp[i].uid, sizeof(utmp[i].uid)) > 0 &&
toread(cfd, utmp[i].friend, sizeof(utmp[i].friend)) > 0 &&
toread(cfd, utmp[i].reject, sizeof(utmp[i].reject)) > 0 ){
if( utmp[i].uid )
initdata(i);
}
else
for( ; i < USHM_SIZE ; ++i )
utmp[i].uid = 0;
close(cfd);
fprintf(stderr, "%d users synced\n", nSynced);
}
void processlogin(int cfd, int uid, int index)
{
if( toread(cfd, utmp[index].friend, sizeof(utmp[index].friend)) > 0 &&
toread(cfd, utmp[index].reject, sizeof(utmp[index].reject)) > 0 ){
/* 因為 logout 的時候並不會通知 utmpserver , 可能會查到一些
已經 logout 的帳號。所以不能只取 MAX_FRIEND 而要多取一些 */
#define MAX_FS (2 * MAX_FRIEND)
int iu, nFrs, stat, rstat;
ocfs_t fs[MAX_FS];
utmp[index].uid = uid;
initdata(index);
for( nFrs = iu = 0 ; iu < USHM_SIZE && nFrs < MAX_FS ; ++iu )
if( iu != index && utmp[iu].uid ){
if( (stat = set_friend_bit(index, iu)) ){
rstat = reverse_friend_stat(stat);
fs[nFrs].index = iu;
fs[nFrs].uid = utmp[iu].uid;
fs[nFrs].friendstat = (stat << 24) + iu;
fs[nFrs].rfriendstat = (rstat << 24) + index;
++nFrs;
}
}
towrite(cfd, &fs, sizeof(ocfs_t) * nFrs);
}
close(cfd);
}
#ifdef NOFLOODING
void flushwaitqueue(void)
{
int i;
for( i = 0 ; i < nWaits ; ++i )
processlogin(waitqueue[i].fd, waitqueue[i].uid, waitqueue[i].index);
lastflushtime = time(NULL);
nWaits = 0;
memset(flooding, 0, sizeof(flooding));
}
#endif
/* XXX 具有被 DoS 的可能, 請用 firewall 之類擋起來 */
int main(int argc, char **argv)
{
struct sockaddr_in clientaddr;
int ch, port = 5120, sfd, cfd, len, index, uid;
char *iface_ip = NULL;
while( (ch = getopt(argc, argv, "p:i:h")) != -1 )
switch( ch ){
case 'p':
port = atoi(optarg);
break;
case 'i':
iface_ip = optarg;
break;
case 'h':
default:
fprintf(stderr, "usage: utmpserver [-i interface_ip] [-p port]\n");
return 1;
}
if( (sfd = tobind(iface_ip, port)) < 0 )
return 1;
#ifdef NOFLOODING
lastflushtime = time(NULL);
#endif
while( 1 ){
#ifdef NOFLOODING
if( lastflushtime < (time(NULL) - 1800) )
flushwaitqueue();
#endif
len = sizeof(clientaddr);
if( (cfd = accept(sfd, (struct sockaddr *)&clientaddr, &len)) < 0 ){
if( errno != EINTR )
sleep(1);
continue;
}
toread(cfd, &index, sizeof(index));
if( index == -1 ){
syncutmp(cfd);
continue;
}
if( toread(cfd, &uid, sizeof(uid)) > 0 ){
if( !(0 < uid || uid > MAX_USERS) ){ /* for safety */
close(cfd);
continue;
}
#ifdef NOFLOODING
if( (time(NULL) - flooding[uid].lasttime) < 20 )
++flooding[uid].count;
if( flooding[uid].count > 10 ){
if( nWaits == MAXWAIT )
flushwaitqueue();
waitqueue[nWaits].uid = uid;
waitqueue[nWaits].index = index;
waitqueue[nWaits].fd = cfd;
++nWaits;
continue;
}
flooding[uid].lasttime = time(NULL);
#endif
/* cfd will be closed in processlogin() */
processlogin(cfd, uid, index);
}
}
return 0;
}
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