fix ip packet forwarding to not stomp on headers when fragmented;

[unix-history] / usr / src / sys / netinet / ip_output.c

diff --git a/usr/src/sys/netinet/ip_output.c b/usr/src/sys/netinet/ip_output.c
index 034d856..10453c9 100644 (file)
--- a/usr/src/sys/netinet/ip_output.c
+++ b/usr/src/sys/netinet/ip_output.c
@@ -1,4 +1,4 @@
-/*     ip_output.c     1.46    83/02/10        */
+/*     ip_output.c     1.47    83/05/12        */

 
 #include "../h/param.h"
 #include "../h/mbuf.h"
 
 #include "../h/param.h"
 #include "../h/mbuf.h"


@@ -18,11 +18,11 @@
 
 int    ipnorouteprint = 0;
 
 
 int    ipnorouteprint = 0;
 

-ip_output(m, opt, ro, allowbroadcast)
+ip_output(m, opt, ro, flags)

        struct mbuf *m;
        struct mbuf *opt;
        struct route *ro;
        struct mbuf *m;
        struct mbuf *opt;
        struct route *ro;

-       int allowbroadcast;
+       int flags;

 {
        register struct ip *ip = mtod(m, struct ip *);
        register struct ifnet *ifp;
 {
        register struct ip *ip = mtod(m, struct ip *);
        register struct ifnet *ifp;


@@ -35,10 +35,12 @@ ip_output(m, opt, ro, allowbroadcast)
        /*
         * Fill in IP header.
         */
        /*
         * Fill in IP header.
         */

-       ip->ip_v = IPVERSION;

        ip->ip_hl = hlen >> 2;
        ip->ip_hl = hlen >> 2;

-       ip->ip_off &= IP_DF;
-       ip->ip_id = htons(ip_id++);
+       if ((flags & IP_FORWARDING) == 0) {
+               ip->ip_v = IPVERSION;
+               ip->ip_off &= IP_DF;
+               ip->ip_id = htons(ip_id++);
+       }

 
        /*
         * Route packet.
 
        /*
         * Route packet.


@@ -52,19 +54,23 @@ ip_output(m, opt, ro, allowbroadcast)
                ro->ro_dst.sa_family = AF_INET;
                ((struct sockaddr_in *)&ro->ro_dst)->sin_addr = ip->ip_dst;
                /*
                ro->ro_dst.sa_family = AF_INET;
                ((struct sockaddr_in *)&ro->ro_dst)->sin_addr = ip->ip_dst;
                /*

-                * If routing to interface only, short circuit routing lookup.
+                * If routing to interface only,
+                * short circuit routing lookup.

                 */
                 */

-               if (ro == &routetoif) {
-                       /* check ifp is AF_INET??? */
+               if (flags & IP_ROUTETOIF) {

                        ifp = if_ifonnetof(in_netof(ip->ip_dst));
                        ifp = if_ifonnetof(in_netof(ip->ip_dst));

-                       if (ifp == 0)
-                               goto unreachable;
+                       if (ifp == 0) {
+                               error = ENETUNREACH;
+                               goto bad;
+                       }

                        goto gotif;
                }
                rtalloc(ro);
        }
                        goto gotif;
                }
                rtalloc(ro);
        }

-       if (ro->ro_rt == 0 || (ifp = ro->ro_rt->rt_ifp) == 0)
-               goto unreachable;
+       if (ro->ro_rt == 0 || (ifp = ro->ro_rt->rt_ifp) == 0) {
+               error = ENETUNREACH;
+               goto bad;
+       }

        ro->ro_rt->rt_use++;
        if (ro->ro_rt->rt_flags & RTF_GATEWAY)
                dst = &ro->ro_rt->rt_gateway;
        ro->ro_rt->rt_use++;
        if (ro->ro_rt->rt_flags & RTF_GATEWAY)
                dst = &ro->ro_rt->rt_gateway;


@@ -89,7 +95,7 @@ gotif:
                        error = EADDRNOTAVAIL;
                        goto bad;
                }
                        error = EADDRNOTAVAIL;
                        goto bad;
                }

-               if (!allowbroadcast) {
+               if ((flags & IP_ALLOWBROADCAST) == 0) {

                        error = EACCES;
                        goto bad;
                }
                        error = EACCES;
                        goto bad;
                }


@@ -173,15 +179,10 @@ gotif:
        m_freem(m);
        goto done;
 
        m_freem(m);
        goto done;
 

-unreachable:
-       if (ipnorouteprint)
-               printf("no route to %x (from %x, len %d)\n",
-                   ip->ip_dst.s_addr, ip->ip_src.s_addr, ip->ip_len);
-       error = ENETUNREACH;

 bad:
        m_freem(m);
 done:
 bad:
        m_freem(m);
 done:

-       if (ro == &iproute && ro->ro_rt)
+       if (ro == &iproute && (flags & IP_ROUTETOIF) == 0 && ro->ro_rt)

                RTFREE(ro->ro_rt);
        return (error);
 }
                RTFREE(ro->ro_rt);
        return (error);
 }