main.c

来自「bbs server linux平台下软件源码」· C语言 代码 · 共 179 行

#include "bbs.h"

#include <sys/ipc.h>
#include <sys/msg.h>
#include <signal.h>

#ifdef HAVE_PERSONAL_DNS
extern int update_dns(const char *server, const char *zone, const char *keyname, const char *key, const char *host, const char *ip, int ttl);

#define MAX_COUNT 100
#define MAX_REQUEST 100000      //after MAX_REQUEST times,fork a new nsupdate
char update_key[100];
char update_keyname[20];
char dns_server[50];
char dns_zone[50];

unsigned int dns_ttl;
FILE *nsupdate_pipe = NULL;

int reread;
bool doflush;
int getconf(char *key, char *value, int len)
{
    char *data;

    data = sysconf_str(key);
    if (data == NULL) {
        return -1;
    }
    strncpy(value, data, len - 1);
    value[len - 1] = 0;
    return 0;
}

int readconfig()
{
    if (nsupdate_pipe != NULL) {
        fprintf(nsupdate_pipe, "quit\n");
        pclose(nsupdate_pipe);
    }
    if (getconf("DNS_UPDATE_ZONE", dns_zone, 50) != 0) {
        bbslog("3error", "please configure dns_update_key!\n");
        return -1;
    }

    if (getconf("DNS_UPDATE_KEYNAME", update_keyname, 20) != 0) {
        bbslog("3error", "please configure dns_update_key!\n");
        return -1;
    }

    if (getconf("DNS_UPDATE_KEY", update_key, 99) != 0) {
        bbslog("3error", "please configure dns updat_key!\n");
        return -1;
    }
    if (getconf("DNS_UPDATE_SERVER", dns_server, 50) != 0) {
        bbslog("3error", "please configure dns update server!\n");
        return -1;
    }
    dns_ttl = sysconf_eval("DNS_TTL", 60);

    nsupdate_pipe = popen("nsupdate 2>&1 > reclog/nsupdate.log", "w");
    if (nsupdate_pipe == NULL) {
        bbslog("3error", "can't open nsupdate:%s", strerror(errno));
        return -1;
    }
    fprintf(nsupdate_pipe, "server %s\n", dns_server);
    fprintf(nsupdate_pipe, "zone %s\n", dns_zone);
    fprintf(nsupdate_pipe, "key %s %s\n", update_keyname, update_key);
    fflush(nsupdate_pipe);
    return 0;
}

static void reconfig(int signo)
{
    doflush = 1;
    reread = 1;
}

static void flush_buffer(int signo)
{
    doflush = 1;
    alarm(60);                  // 1 minutes flush
}

static void reaper()
{
    while (waitpid(-1, NULL, WNOHANG | WUNTRACED) > 0);
}

#endif

int main()
{
#ifdef HAVE_PERSONAL_DNS
    int msqid, dnscount, requestcount;

    struct sigaction act;
    struct msqid_ds msqds;
    struct dns_msgbuf msg;

    umask(027);

    chdir(BBSHOME);
    reread = 0;

    dnscount = 0;
    act.sa_handler = reconfig;
    sigaction(SIGHUP, &act, NULL);

    act.sa_handler = reconfig;
    sigaction(SIGPIPE, &act, NULL);

    act.sa_handler = flush_buffer;
    sigaction(SIGALRM, &act, NULL);
#ifdef AIX
    act.sa_handler = NULL;
    act.sa_flags = SA_RESTART | SA_NOCLDWAIT;
    sigaction(SIGCHLD, &act, NULL);
#else
    act.sa_handler = reaper;
    act.sa_flags = SA_RESTART;
    sigaction(SIGCHLD, &act, NULL);
#endif

    setuid(BBSUID);
    setreuid(BBSUID, BBSUID);
    setgid(BBSGID);
    setregid(BBSGID, BBSGID);
    dodaemon("bbsnsupdated", true, false);
    if (readconfig() != 0)
        return -1;

    msqid = msgget(sysconf_eval("BBSDNS_MSG", 0x999), IPC_CREAT | 0664);
    if (msqid < 0)
        return -1;
    msgctl(msqid, IPC_STAT, &msqds);
    msqds.msg_qbytes = 50 * 1024;
    msgctl(msqid, IPC_SET, &msqds);
    alarm(60);                  // 1 minutes flush
    while (1) {
        int retv;

        retv = msgrcv(msqid, &msg, sizeof(msg) - sizeof(msg.mtype), 0, MSG_NOERROR);
        if (retv < 0) {
            if (errno != EINTR) {
                bbslog("3error", "bbsupdated(rcvlog):%s", strerror(errno));
                exit(0);
            }
        } else {
            fprintf(nsupdate_pipe, "update delete %s A\n", msg.userid);
            fprintf(nsupdate_pipe, "update add %s %d A %s\n", msg.userid, dns_ttl, msg.ip);
            dnscount++;
            requestcount++;
            if (dnscount >= MAX_COUNT)
                doflush = true;
            bbslog("3error", "update dns %s %s", msg.userid, msg.ip);
        }

        if (doflush && dnscount) {
            dnscount = 0;
            fprintf(nsupdate_pipe, "send\n");
            fflush(nsupdate_pipe);
        }
        if (requestcount > MAX_REQUEST) {
            reread = true;
            requestcount = 0;
        }
        if (reread)
            if (readconfig() != 0) {
                bbslog("3error", "bbsupdated config error");
            }
    }
    fprintf(nsupdate_pipe, "quit\n");
    pclose(nsupdate_pipe);
#else
    return 0;
#endif
}