r5405: try to use NBT name pointers when a netbios name is repeated in a NBT

packet. This allows much longer names to fit within the limits of NBT
name packets (rfc1002.txt also says this should be done, although
Samba3 never generates them).

The main reason for doing this is it means that our NBT name pointer
decoding code is tested with the smbtorture tests
(This used to be commit 6e2feef125daceb143c44c0c4ab73b010b311792)

diff --git a/source4/libcli/nbt/nbtname.c b/source4/libcli/nbt/nbtname.c
index bf545a63743d2ae1d6590c02bb3362ce37644b9d..12b8884e2d5c98bcaf0262a032cb528ccf99d783 100644 (file)
--- a/source4/libcli/nbt/nbtname.c
+++ b/source4/libcli/nbt/nbtname.c
@@ -214,8 +214,9 @@ NTSTATUS ndr_push_nbt_name(struct ndr_push *ndr, int ndr_flags, struct nbt_name
        uint_t num_components;
        uint8_t *components[MAX_COMPONENTS];
        char *dscope=NULL, *p;
-       uint8_t *cname;
+       uint8_t *cname, *fullname;
        int i;
+       int fulllen;
 
        if (!(ndr_flags & NDR_SCALARS)) {
                return NT_STATUS_OK;
@@ -246,14 +247,31 @@ NTSTATUS ndr_push_nbt_name(struct ndr_push *ndr, int ndr_flags, struct nbt_name
        if (num_components == MAX_COMPONENTS) {
                return NT_STATUS_BAD_NETWORK_NAME;
        }
+
+       fullname = talloc_asprintf(ndr, "%c%s", (unsigned char)strlen(cname), cname);
+       NT_STATUS_HAVE_NO_MEMORY(fullname);
                
-       /* push the components */
-       for (i=0;i<num_components;i++) {
-               uint8_t len = strlen(components[i]);
-               NDR_CHECK(ndr_push_uint8(ndr, NDR_SCALARS, len));
-               NDR_CHECK(ndr_push_bytes(ndr, components[i], len));
+       for (i=1;i<num_components;i++) {
+               fullname = talloc_asprintf_append(fullname, "%c%s", 
+                                                 (unsigned char)strlen(components[i]), components[i]);
+               NT_STATUS_HAVE_NO_MEMORY(fullname);
        }
-       NDR_CHECK(ndr_push_uint8(ndr, NDR_SCALARS, 0));
+
+       /* see if we can find the fullname in the existing packet - if
+          so, we can use a NBT name pointer. This allows us to fit
+          longer names into the packet */
+       fulllen = strlen(fullname)+1;
+       for (i=0;i + fulllen < ndr->offset;i++) {
+               if (ndr->data[i] == fullname[0] &&
+                   memcmp(fullname, &ndr->data[i], fulllen) == 0) {
+                       talloc_free(fullname);
+                       return ndr_push_uint16(ndr, NDR_SCALARS, 0xC000 | i);
+               }
+       }
+
+       NDR_CHECK(ndr_push_bytes(ndr, fullname, fulllen));
+
+       talloc_free(fullname);
 
        return NT_STATUS_OK;
 }