Accept ms-wins settings provided by server

The PPP servers of some UMTS/HSPA modems, including the Huawei E220
and E620, will send WINS server settings and insist that the client
accepts these. If the client does not do so, the modem will sometimes
provide bogus DNS server addresses like 10.11.12.13 and 10.11.12.14.

If we receive ms-wins settings from the server, save and include them
in our ConfReqs.

See also discussions at

  http://thread.gmane.org/gmane.linux.ppp/2721
  http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=445711

[paulus@samba.org: In fact what seems to happen is that the modem naks
IPCP conf-reqs with bogus values until it manages to communicate on the
network.  It's not clear that asking for the ms-wins stuff is essential
but it seems that sometimes it helps.]

Signed-off-by: Marcus Better <marcus@better.se>
Signed-off-by: Paul Mackerras <paulus@samba.org>

diff --git a/pppd/ipcp.c b/pppd/ipcp.c
index b7da1f780fb3592d5096b5a9ec6c46306d9860ed..cb873bbd3e836a8501a089fab1786cf8dc68b86f 100644 (file)
--- a/pppd/ipcp.c
+++ b/pppd/ipcp.c
@@ -723,7 +723,8 @@ ipcp_cilen(f)
 #define LENCIADDRS(neg)                (neg ? CILEN_ADDRS : 0)
 #define LENCIVJ(neg, old)      (neg ? (old? CILEN_COMPRESS : CILEN_VJ) : 0)
 #define LENCIADDR(neg)         (neg ? CILEN_ADDR : 0)
-#define LENCIDNS(neg)          (neg ? (CILEN_ADDR) : 0)
+#define LENCIDNS(neg)          LENCIADDR(neg)
+#define LENCIWINS(neg)         LENCIADDR(neg)
 
     /*
      * First see if we want to change our options to the old
@@ -745,7 +746,9 @@ ipcp_cilen(f)
            LENCIVJ(go->neg_vj, go->old_vj) +
            LENCIADDR(go->neg_addr) +
            LENCIDNS(go->req_dns1) +
-           LENCIDNS(go->req_dns2)) ;
+           LENCIDNS(go->req_dns2) +
+           LENCIWINS(go->winsaddr[0]) +
+           LENCIWINS(go->winsaddr[1])) ;
 }
 
 
@@ -819,6 +822,19 @@ ipcp_addci(f, ucp, lenp)
            neg = 0; \
     }
 
+#define ADDCIWINS(opt, addr) \
+    if (addr) { \
+       if (len >= CILEN_ADDR) { \
+           u_int32_t l; \
+           PUTCHAR(opt, ucp); \
+           PUTCHAR(CILEN_ADDR, ucp); \
+           l = ntohl(addr); \
+           PUTLONG(l, ucp); \
+           len -= CILEN_ADDR; \
+       } else \
+           addr = 0; \
+    }
+
     ADDCIADDRS(CI_ADDRS, !go->neg_addr && go->old_addrs, go->ouraddr,
               go->hisaddr);
 
@@ -831,6 +847,10 @@ ipcp_addci(f, ucp, lenp)
 
     ADDCIDNS(CI_MS_DNS2, go->req_dns2, go->dnsaddr[1]);
 
+    ADDCIWINS(CI_MS_WINS1, go->winsaddr[0]);
+
+    ADDCIWINS(CI_MS_WINS2, go->winsaddr[1]);
+    
     *lenp -= len;
 }
 
@@ -1185,6 +1205,15 @@ ipcp_nakci(f, p, len, treat_as_reject)
            try.req_dns2 = 1;
            no.req_dns2 = 1;
            break;
+       case CI_MS_WINS1:
+       case CI_MS_WINS2:
+           if (cilen != CILEN_ADDR)
+               goto bad;
+           GETLONG(l, p);
+           ciaddr1 = htonl(l);
+           if (ciaddr1)
+               try.winsaddr[citype == CI_MS_WINS2] = ciaddr1;
+           break;
        }
        p = next;
     }
@@ -1301,6 +1330,21 @@ ipcp_rejci(f, p, len)
        try.neg = 0; \
     }
 
+#define REJCIWINS(opt, addr) \
+    if (addr && \
+       ((cilen = p[1]) == CILEN_ADDR) && \
+       len >= cilen && \
+       p[0] == opt) { \
+       u_int32_t l; \
+       len -= cilen; \
+       INCPTR(2, p); \
+       GETLONG(l, p); \
+       cilong = htonl(l); \
+       /* Check rejected value. */ \
+       if (cilong != addr) \
+           goto bad; \
+       try.winsaddr[opt == CI_MS_WINS2] = 0; \
+    }
 
     REJCIADDRS(CI_ADDRS, !go->neg_addr && go->old_addrs,
               go->ouraddr, go->hisaddr);
@@ -1314,6 +1358,10 @@ ipcp_rejci(f, p, len)
 
     REJCIDNS(CI_MS_DNS2, req_dns2, go->dnsaddr[1]);
 
+    REJCIWINS(CI_MS_WINS1, go->winsaddr[0]);
+
+    REJCIWINS(CI_MS_WINS2, go->winsaddr[1]);
+
     /*
      * If there are any remaining CIs, then this packet is bad.
      */