Re: DHCP support

[Marco Gerards]

"Neal H. Walfield" <neal@walfield.org> writes:

> The patch looks basically good, however, as Alfred already pointed
> out, even if this is a hack we should still support dhcp per-device
> and not just hardcode eth0.

[...]

> Also, a small typo: it should be `started *with* the'.

Both issues are fixed now.  And I have changed the way the patch works
a bit.  Now it should work for other devices too, perhaps even for
multiple devices, but I can't test this here.

Anyway, I am quite happy with the patch as it is.  Roland, can I
commit this patch?

Thanks,
Marco


2005-01-06  Marco Gerards  <metgerards@student.han.nl>

        * options.c (options): Add the option `dhcp'.
        (parse_hook_add_interface): Initialize the `dhcp' member for the
        parse hook.
        (parse_opt): In case pfinet is started with the argument `--dhcp',
        set the address to `0.0.0.0', the netmask to `255.0.0.0' and add
        the route for `0.0.0.0' so broadcasting works.

        * linux-src/net/ipv4/devinet.c (inet_insert_ifa) [_HURD_]: Don't
        fail when the address is `0.0.0.0'.


Index: pfinet/options.c
===================================================================
RCS file: /cvsroot/hurd/hurd/pfinet/options.c,v
retrieving revision 1.11
diff -u -p -r1.11 options.c
--- pfinet/options.c    18 Jul 2001 16:56:57 -0000      1.11
+++ pfinet/options.c    6 Jan 2005 18:52:30 -0000
@@ -1,6 +1,6 @@
 /* Pfinet option parsing
 
-   Copyright (C) 1996,97,2000,01 Free Software Foundation, Inc.
+   Copyright (C) 1996,97,2000,01,2005 Free Software Foundation, Inc.
 
    Written by Miles Bader <miles@gnu.org>
 
@@ -60,6 +60,7 @@ static const struct argp_option options[
   {"netmask",   'm', "MASK",    0, "Set the netmask"},
   {"peer",      'p', "ADDRESS", 0, "Set the peer address"},
   {"gateway",   'g', "ADDRESS", 0, "Set the default gateway"},
+  {"dhcp",     'd', 0        , 0, "Prepare pfinet for dhcp"},
   {"shutdown",  's', 0,         0, "Shut it down"},
   {0}
 };
@@ -76,6 +77,9 @@ struct parse_interface
 
   /* New values to apply to it.  */
   uint32_t address, netmask, peer, gateway;
+
+  /* Set to one if the interface is configured for DHCP.  */
+  int dhcp;
 };
 
 /* Used to hold data during argument parsing.  */
@@ -108,6 +112,7 @@ parse_hook_add_interface (struct parse_h
   h->curint->netmask = INADDR_NONE;
   h->curint->peer = INADDR_NONE;
   h->curint->gateway = INADDR_NONE;
+  h->curint->dhcp = 0;
   return 0;
 }
 
@@ -189,6 +194,11 @@ parse_opt (int opt, char *arg, struct ar
                  "%s: Illegal or undefined network address", arg);
        }
       break;
+    case 'd':
+      h->curint->dhcp = 1;
+      h->curint->address = ADDR ("0.0.0.0", "address");
+      h->curint->netmask = ADDR ("255.0.0.0", "netmask");
+      break;
     case 'm':
       h->curint->netmask = ADDR (arg, "netmask"); break;
     case 'p':
@@ -315,6 +325,55 @@ parse_opt (int opt, char *arg, struct ar
          }
       }
 
+      /*  Setup the routing required for DHCP. */
+      for (in = h->interfaces; in < h->interfaces + h->num_interfaces; in++)
+       if (in->dhcp)
+         {
+           struct kern_rta rta;
+           struct
+           {
+             struct nlmsghdr nlh;
+             struct rtmsg rtm;
+           } req;
+           struct fib_table *tb;
+           struct rtentry route;
+           struct sockaddr_in *dst;
+           struct device *dev;
+           
+           dst = (struct sockaddr_in *) &route.rt_dst;
+           
+           dev = dev_get (in->device->name);
+           if (!dev)
+             {
+               __mutex_unlock (&global_lock);
+               FAIL (ENODEV, 17, 0, "unknown device");
+             }
+           
+           /* Simulate the SIOCADDRT behavior.  */
+           bzero (&route, sizeof (struct rtentry));
+           bzero (&req.rtm, sizeof req.rtm);
+           bzero (&rta, sizeof rta);
+           req.nlh.nlmsg_type = RTM_NEWROUTE;
+           req.nlh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE;
+           req.rtm.rtm_protocol = RTPROT_BOOT;
+           req.rtm.rtm_scope = RT_SCOPE_LINK;
+           req.rtm.rtm_type = RTN_UNICAST;
+           rta.rta_dst = &dst->sin_addr.s_addr;
+           rta.rta_oif = &dev->ifindex;
+           
+           tb = fib_new_table (req.rtm.rtm_table);
+           if (tb)
+             err = tb->tb_insert (tb, &req.rtm, &rta, &req.nlh, NULL);
+           else
+             err = ENOBUFS;
+           
+           if (err)
+             {
+               __mutex_unlock (&global_lock);
+               FAIL (err, 17, 0, "cannot add route");
+             }
+         }
+      
       __mutex_unlock (&global_lock);
 
       /* Fall through to free hook.  */
Index: pfinet/linux-src/net/ipv4/devinet.c
===================================================================
RCS file: /cvsroot/hurd/hurd/pfinet/linux-src/net/ipv4/devinet.c,v
retrieving revision 1.8
diff -u -p -r1.8 devinet.c
--- pfinet/linux-src/net/ipv4/devinet.c 18 Jul 2001 17:37:13 -0000      1.8
+++ pfinet/linux-src/net/ipv4/devinet.c 6 Jan 2005 18:52:32 -0000
@@ -214,10 +214,12 @@ inet_insert_ifa(struct in_device *in_dev
 {
        struct in_ifaddr *ifa1, **ifap, **last_primary;
 
+#ifndef _HURD_
        if (ifa->ifa_local == 0) {
                inet_free_ifa(ifa);
                return 0;
        }
+#endif
 
        ifa->ifa_flags &= ~IFA_F_SECONDARY;
        last_primary = &in_dev->ifa_list;