Fix the decoding of SLP attributes. Open SLP has the ability to pass back multiple attribute types in each reply. Previously the dissector only would dissect address attributes. The change adds parsing of attributes and proper dissection of names and address attributes contained in the same reply payload.

svn path=/trunk/; revision=19060

1 files changed, 97 insertions, 60 deletions

diff --git a/epan/dissectors/packet-srvloc.c b/epan/dissectors/packet-srvloc.c
index ffb9c80ec3..e1021b4f61 100644
--- a/epan/dissectors/packet-srvloc.c
+++ b/epan/dissectors/packet-srvloc.c
@@ -152,6 +152,7 @@ static int hf_srvloc_url_urllen = -1;
 static int hf_srvloc_url_url = -1;
 static int hf_srvloc_url_numauths = -1;
 static int hf_srvloc_add_ref_ip = -1;
+static int hf_srvloc_srvrply_svcname = -1;
 
 
 static gint ett_srvloc = -1;
@@ -498,6 +499,11 @@ unicode_to_bytes(tvbuff_t *tvb, int offset, int length, gboolean endianness)
  * The second digit is the socket type: 1 for socket stream (TCP), 2 for datagram (UDP and IPX).
  * The third is the protocol: 6 for TCP, 17 for UDP, and 1000 for IPX.
  * Last is the IP address, in hex, of the interface that is registered (or, in the case of IPX, an IPX network number).
+ *
+ * OpenSLP supports multiple attribute replies so we need to parse the attribute name and then decode accourdingly.
+ * We currently only parse the (non-utf8) attributes:
+ * svcname
+ * svcaddr
 */
 static void
 attr_list(proto_tree *tree, int hf, tvbuff_t *tvb, int offset, int length,
@@ -533,70 +539,97 @@ attr_list(proto_tree *tree, int hf, tvbuff_t *tvb, int offset, int length,
     switch (encoding) {
 
     case CHARSET_ISO_10646_UCS_2:
-
-        tmp = tvb_get_ephemeral_faked_unicode(tvb, offset, length/2, FALSE);
-        type_len = strcspn(tmp, "=");
-        attr_type = tvb_get_ephemeral_faked_unicode(tvb, offset+2, type_len-1, FALSE);
-        proto_tree_add_string(tree, hf, tvb, offset, type_len*2, attr_type);
-        i=1;
-        for (foffset = offset + ((type_len*2)+2); foffset<length; foffset += 2) {
-
-            ti = proto_tree_add_text(tree, tvb, foffset, -1, "Item %d", i);
-            srvloc_tree = proto_item_add_subtree(ti, ett_srvloc);
-
-            svc = tvb_get_guint8(tvb, foffset+1);
-			proto_tree_add_text(srvloc_tree, tvb, foffset+1, 1,
-				    "Service Type: %s", val_to_str(svc, srvloc_svc, "Unknown"));
-            ss = tvb_get_guint8(tvb, foffset+5);
-			proto_tree_add_text(srvloc_tree, tvb, foffset+5, 1,
-				    "Communication Type: %s", val_to_str(ss, srvloc_ss, "Unknown"));
-            foffset += 9;
-            if (svc == 50) {
-                if (tvb_get_guint8(tvb, foffset)==54) { /* TCP */
-                    prot = tvb_get_guint8(tvb, foffset);
-                    proto_tree_add_text(srvloc_tree, tvb, foffset, 1,
-                            "Protocol: %s", val_to_str(prot, srvloc_prot, "Unknown"));
-                    foffset += 2;
-                }
-                else
-                {
-                    byte_value = unicode_to_bytes(tvb, foffset, 4, FALSE); /* UDP */
-                    prot = atol(byte_value);
-                    proto_tree_add_text(srvloc_tree, tvb, foffset, 4,
-                            "Protocol: %s", val_to_str(prot, srvloc_prot, "Unknown"));
-                    foffset += 4;
-                }
+        while (offset+2<length) {
+            offset += 2;
+            /* If the length passed is longer then the actual payload then this must be an incomplete packet. */
+            if (tvb_length_remaining(tvb, 4)<length) {
+                proto_tree_add_text(tree, tvb, offset, -1, "Status: Too much data to pass inside this protocol. Resubmit request using a streaming protocol like TCP.");
+                proto_tree_add_text(tree, tvb, offset, -1, "Note: Protocol dissection is aborted due to packet overflow. See overflow flag.");
+                break;
             }
-            else
-            {
-                byte_value = unicode_to_bytes(tvb, foffset, 8, FALSE); /* IPX */
-                prot = atol(byte_value);
-                proto_tree_add_text(srvloc_tree, tvb, foffset, 8,
-                            "Protocol: %s", val_to_str(prot, srvloc_prot, "Unknown"));
-                foffset += 8;
+            /* Parse the attribute name */
+            tmp = tvb_get_ephemeral_faked_unicode(tvb, offset, (length-offset)/2, FALSE);
+            type_len = strcspn(tmp, "=");
+            attr_type = tvb_get_ephemeral_faked_unicode(tvb, offset, type_len, FALSE);
+            proto_tree_add_string(tree, hf, tvb, offset, type_len*2, attr_type);
+            offset += (type_len*2)+2;
+            /* If this is the attribute svcname */
+            if (strcmp(attr_type, "svcname-ws")==0) {
+                tmp = tvb_get_ephemeral_faked_unicode(tvb, offset, (length-offset)/2, FALSE);
+                type_len = strcspn(tmp, ")");
+                add_v1_string(tree, hf_srvloc_srvrply_svcname, tvb, offset, type_len*2, encoding);
+                offset += (type_len*2)+4;
+                strcpy(attr_type, "\0");
             }
-            if (svc == 50) {
-                byte_value = unicode_to_bytes(tvb, foffset, 16, TRUE); /* IP Address */
-                sscanf(byte_value,"%x",&prot);
-                proto_tree_add_ipv4(srvloc_tree, hf_srvloc_add_ref_ip, tvb, foffset+2, 16, prot);
-                byte_value = unicode_to_bytes(tvb, foffset+18, 8, FALSE); /* Port */
-                sscanf(byte_value,"%x",&prot);
-                proto_tree_add_text(srvloc_tree, tvb, foffset+18, 8, "Port: %d", prot);
+            /* If this is the attribute svcaddr */
+            if (strcmp(attr_type, "svcaddr-ws")==0) {
+                i=1;
+                for (foffset = offset; foffset<length; foffset += 2) {
+        
+                    ti = proto_tree_add_text(tree, tvb, foffset, -1, "Item %d", i);
+                    srvloc_tree = proto_item_add_subtree(ti, ett_srvloc);
+        
+                    svc = tvb_get_guint8(tvb, foffset+1);
+        			proto_tree_add_text(srvloc_tree, tvb, foffset+1, 1,
+        				    "Service Type: %s", val_to_str(svc, srvloc_svc, "Unknown"));
+                    ss = tvb_get_guint8(tvb, foffset+5);
+        			proto_tree_add_text(srvloc_tree, tvb, foffset+5, 1,
+        				    "Communication Type: %s", val_to_str(ss, srvloc_ss, "Unknown"));
+                    foffset += 9;
+                    if (svc == 50) {
+                        if (tvb_get_guint8(tvb, foffset)==54) { /* TCP */
+                            prot = tvb_get_guint8(tvb, foffset);
+                            proto_tree_add_text(srvloc_tree, tvb, foffset, 1,
+                                    "Protocol: %s", val_to_str(prot, srvloc_prot, "Unknown"));
+                            foffset += 2;
+                        }
+                        else
+                        {
+                            byte_value = unicode_to_bytes(tvb, foffset, 4, FALSE); /* UDP */
+                            prot = atol(byte_value);
+                            proto_tree_add_text(srvloc_tree, tvb, foffset, 4,
+                                    "Protocol: %s", val_to_str(prot, srvloc_prot, "Unknown"));
+                            foffset += 4;
+                        }
+                    }
+                    else
+                    {
+                        byte_value = unicode_to_bytes(tvb, foffset, 8, FALSE); /* IPX */
+                        prot = atol(byte_value);
+                        proto_tree_add_text(srvloc_tree, tvb, foffset, 8,
+                                    "Protocol: %s", val_to_str(prot, srvloc_prot, "Unknown"));
+                        foffset += 8;
+                    }
+                    if (svc == 50) {
+                        byte_value = unicode_to_bytes(tvb, foffset, 16, TRUE); /* IP Address */
+                        sscanf(byte_value,"%x",&prot);
+                        proto_tree_add_ipv4(srvloc_tree, hf_srvloc_add_ref_ip, tvb, foffset+2, 16, prot);
+                        byte_value = unicode_to_bytes(tvb, foffset+18, 8, FALSE); /* Port */
+                        sscanf(byte_value,"%x",&prot);
+                        proto_tree_add_text(srvloc_tree, tvb, foffset+18, 8, "Port: %d", prot);
+                    }
+                    else
+                    {
+                        byte_value = unicode_to_bytes(tvb, foffset+2, 16, FALSE); /* IPX Network Address */
+                        sscanf(byte_value,"%x",&prot);
+                        proto_tree_add_text(srvloc_tree, tvb, foffset+2, 16, "Network: %s", byte_value);
+                        byte_value = unicode_to_bytes(tvb, foffset+18, 24, FALSE); /* IPX Node Address */
+                        sscanf(byte_value,"%x",&prot);
+                        proto_tree_add_text(srvloc_tree, tvb, foffset+18, 24, "Node: %s", byte_value);
+                        byte_value = unicode_to_bytes(tvb, foffset+42, 8, FALSE);  /* Socket */
+                        sscanf(byte_value,"%x",&prot);
+                        proto_tree_add_text(srvloc_tree, tvb, foffset+42, 8, "Socket: %s", byte_value);
+                    }
+                    i++;
+                    foffset += 57;
+                }
+                offset = foffset;
+                strcpy(attr_type, "\0");
             }
-            else
-            {
-                byte_value = unicode_to_bytes(tvb, foffset+2, 16, FALSE); /* IPX Network Address */
-                sscanf(byte_value,"%x",&prot);
-                proto_tree_add_text(srvloc_tree, tvb, foffset+2, 16, "Network: %s", byte_value);
-                byte_value = unicode_to_bytes(tvb, foffset+18, 24, FALSE); /* IPX Node Address */
-                sscanf(byte_value,"%x",&prot);
-                proto_tree_add_text(srvloc_tree, tvb, foffset+18, 24, "Node: %s", byte_value);
-                byte_value = unicode_to_bytes(tvb, foffset+42, 8, FALSE);  /* Socket */
-                sscanf(byte_value,"%x",&prot);
-                proto_tree_add_text(srvloc_tree, tvb, foffset+42, 8, "Socket: %s", byte_value);
+            /* If there are no more supported attributes available then abort dissection */
+            if (strcmp(attr_type, "svcaddr-ws")!=0 && strcmp(attr_type, "svcname-ws")!=0 && strcmp(attr_type, "\0")!=0) {
+                break;
             }
-            i++;
-            foffset += 57;
         }
         break;
 
@@ -1746,6 +1779,10 @@ proto_register_srvloc(void)
 	{ &hf_srvloc_add_ref_ip,
 	  { "IP Address", "srvloc.list.ipaddr", FT_IPv4, BASE_DEC, NULL, 0x0,
 	    "IP Address of SLP server", HFILL}
+	},
+	{ &hf_srvloc_srvrply_svcname,
+	  { "Service Name Value", "srvloc.srvrply.svcname", FT_STRING, BASE_NONE, NULL, 0x0,
+	    "", HFILL}
 	}
     };