Should handle IPv6.

git-svn-id: svn+ssh://svn.dolda2000.com/srv/svn/repos/src/icmp-dn@225 959494ce-11ee-0310-bf91-de5d638817bd

diff --git a/icmpdnd.c b/icmpdnd.c
index 3cd6f5f..dd99326 100644 (file)
--- a/icmpdnd.c
+++ b/icmpdnd.c
@@ -24,6 +24,7 @@
 #include <syslog.h>
 #include <time.h>
 #include <sys/socket.h>
+#include <sys/poll.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <netinet/ip.h>
@@ -130,14 +131,16 @@ void cksum(void *hdr, size_t len)
 
 int main(int argc, char **argv)
 {
-    int ret;
-    int c, s, namelen, datalen;
+    int i, n, ret;
+    int c, cs, s4, s6, namelen, datalen;
     int daemonize, ttl;
     unsigned char buf[65536];
-    struct sockaddr_in name;
+    struct sockaddr_storage name;
     struct reqhdr req;
     struct rephdr rep;
     struct iphdr iphdr;
+    size_t hdrlen;
+    struct pollfd pfd[2];
     time_t curtime, lasterr;
     
     daemonize = 1;
@@ -159,27 +162,39 @@ int main(int argc, char **argv)
        }
     }
     
-    if((s = socket(PF_INET, SOCK_RAW, IPPROTO_ICMP)) < 0) {
-       perror("could not create raw socket");
+    s4 = socket(PF_INET, SOCK_RAW, IPPROTO_ICMP);
+    s6 = socket(PF_INET6, SOCK_RAW, IPPROTO_ICMP);
+    if((s4 < 0) && (s6 < 0)) {
+       perror("could not open raw socket");
        exit(1);
     }
     
     if(daemonize)
        daemon(0, 0);
     
-    openlog("icmpdnd", LOG_PID, LOG_DAEMON);
+    openlog("icmpdnd", LOG_PID | LOG_NDELAY, LOG_DAEMON);
     
     alive = 1;
     lasterr = 0;
     while(alive) {
-       namelen = sizeof(name);
-       ret = recvfrom(s, buf, sizeof(buf), 0, (struct sockaddr *)&name, &namelen);
-       
+       n = 0;
+       if(s4 >= 0) {
+           pfd[n].fd = s4;
+           pfd[n].events = POLLIN;
+           n++;
+       }
+       if(s6 >= 0) {
+           pfd[n].fd = s6;
+           pfd[n].events = POLLIN;
+           n++;
+       }
+       ret = poll(pfd, n, -1);
+
        curtime = time(NULL);
        if(ret < 0) {
            if(errno == EINTR)
                continue;
-           syslog(LOG_ERR, "error in receiving datagram: %m");
+           syslog(LOG_ERR, "error while polling sockets: %m");
            if(lasterr == curtime) {
                syslog(LOG_CRIT, "exiting due to repeated errors");
                exit(1);
@@ -187,31 +202,56 @@ int main(int argc, char **argv)
            lasterr = curtime;
        }
        
-       if(ret < sizeof(iphdr) + sizeof(req))
-           continue;
-       memcpy(&iphdr, buf, sizeof(iphdr));
-       memcpy(&req, buf + sizeof(iphdr), sizeof(req));
-       if(iphdr.protocol != IPPROTO_ICMP)
-           continue;
-       if(req.type != ICMP_NAMEREQ)
-           continue;
-       rep.type = ICMP_NAMEREP;
-       rep.code = 0;
-       rep.id = req.id;
-       rep.seq = req.seq;
-       rep.ttl = htonl(ttl);
-       memcpy(buf, &rep, sizeof(rep));
-       datalen = filldn(buf + sizeof(rep));
+       for(i = 0; i < n; i++) {
+           if((pfd[i].revents & POLLIN) == 0)
+               continue;
+           cs = pfd[i].fd;
+           namelen = sizeof(name);
+           memset(&name, 0, sizeof(name));
+           ret = recvfrom(cs, buf, sizeof(buf), 0, (struct sockaddr *)&name, &namelen);
+           if(ret < 0) {
+               syslog(LOG_WARNING, "error while receiving datagram: %m");
+               continue;
+           }
+           
+           if(cs == s4) {
+               if(ret < sizeof(iphdr) + sizeof(req))
+                   continue;
+               hdrlen = sizeof(iphdr);
+               memcpy(&iphdr, buf, sizeof(iphdr));
+               if(iphdr.protocol != IPPROTO_ICMP)
+                   continue;
+           } else if(cs == s6) {
+               if(ret < sizeof(req))
+                   continue;
+               ((struct sockaddr_in6 *)&name)->sin6_port = 0;
+               hdrlen = 0;
+           } else {
+               syslog(LOG_CRIT, "strangeness!");
+               abort();
+           }
+           memcpy(&req, buf + hdrlen, sizeof(req));
+           if(req.type != ICMP_NAMEREQ)
+               continue;
+           rep.type = ICMP_NAMEREP;
+           rep.code = 0;
+           rep.id = req.id;
+           rep.seq = req.seq;
+           rep.ttl = htonl(ttl);
+           memcpy(buf, &rep, sizeof(rep));
+           datalen = filldn(buf + sizeof(rep));
        
-       cksum(buf, datalen + sizeof(rep));
+           cksum(buf, datalen + sizeof(rep));
        
-       /* XXX: The correct source address needs to be filled in from
-        * the request's destination address. */
-       ret = sendto(s, buf, datalen + sizeof(rep), 0, (struct sockaddr *)&name, namelen);
-       if(ret < 0)
-           syslog(LOG_WARNING, "error in sending reply: %m");
+           /* XXX: The correct source address needs to be filled in from
+            * the request's destination address. */
+           ret = sendto(cs, buf, datalen + sizeof(rep), 0, (struct sockaddr *)&name, namelen);
+           if(ret < 0)
+               syslog(LOG_WARNING, "error in sending reply: %m");
+       }
     }
     
-    close(s);
+    close(s4);
+    close(s6);
     return(0);
 }