move the conversation find and create into dissect_iscsi() from dissect_iscsi_pdu() so it will be easier to add a session wide state structure to iscsi.

later this soon to be implemented structure (and not the conversation) will 
hold the information we need to track  wether
digests etc are in use or not.

this also allows some minor indentation cleanups as well.



svn path=/trunk/; revision=11848

1 files changed, 58 insertions, 64 deletions

diff --git a/epan/dissectors/packet-iscsi.c b/epan/dissectors/packet-iscsi.c
index 1930e88ee2..cd0528c714 100644
--- a/epan/dissectors/packet-iscsi.c
+++ b/epan/dissectors/packet-iscsi.c
@@ -800,7 +800,7 @@ handleDataSegmentAsTextKeys(proto_item *ti, tvbuff_t *tvb, guint offset, guint d
 
 /* Code to actually dissect the packets */
 static void
-dissect_iscsi_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint offset, guint8 opcode, const char *opcode_str, guint32 data_segment_len) {
+dissect_iscsi_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint offset, guint8 opcode, const char *opcode_str, guint32 data_segment_len, conversation_t *conversation) {
 
     guint original_offset = offset;
     proto_tree *ti = NULL;
@@ -808,7 +808,6 @@ dissect_iscsi_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint off
     gboolean S_bit=FALSE;
     guint cdb_offset = offset + 32; /* offset of CDB from start of PDU */
     guint end_offset = offset + tvb_length_remaining(tvb, offset);
-    conversation_t *conversation = NULL;
     iscsi_conv_data_t *cdata = NULL;
     scsi_task_id_t task_key;
     int paddedDataSegmentLength = data_segment_len;
@@ -827,84 +826,67 @@ dissect_iscsi_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint off
     if ((opcode == ISCSI_OPCODE_SCSI_RESPONSE) ||
         (opcode == ISCSI_OPCODE_SCSI_DATA_IN) ||
         (opcode == ISCSI_OPCODE_SCSI_DATA_OUT)) {
-        conversation = find_conversation (&pinfo->src, &pinfo->dst,
-                                          pinfo->ptype, pinfo->srcport,
-                                          pinfo->destport, 0);
-        if (conversation) {
-            if (!pinfo->fd->flags.visited){
-                iscsi_conv_data_t ckey;
-                ckey.conv_idx = conversation->index;
-                ckey.itt = tvb_get_ntohl (tvb, offset+16);
+        if (!pinfo->fd->flags.visited){
+            iscsi_conv_data_t ckey;
+            ckey.conv_idx = conversation->index;
+            ckey.itt = tvb_get_ntohl (tvb, offset+16);
 
-                /* first time we see this packet. check if we can find the request */
-                cdata = (iscsi_conv_data_t *)g_hash_table_lookup (iscsi_req_unmatched, &ckey);
-                if (cdata){
-                    if (cdata->data_in_frame+cdata->data_out_frame+cdata->response_frame==0){
-                        /* this is the first response to the request, add it to the matched table */
-                        g_hash_table_insert (iscsi_req_matched, cdata, cdata);
-                    }
-                    switch(opcode){
-                    case ISCSI_OPCODE_SCSI_RESPONSE:
-                        cdata->response_frame=pinfo->fd->num;
-                        break;
-                    case ISCSI_OPCODE_SCSI_DATA_IN:
-                        /* a bit ugly but we need to check the S bit here */
-                        if(tvb_get_guint8(tvb, offset+1)&ISCSI_SCSI_DATA_FLAG_S){
-                            cdata->response_frame=pinfo->fd->num;
-                        }
-                        cdata->data_in_frame=pinfo->fd->num;
-                        break;
-                    case ISCSI_OPCODE_SCSI_DATA_OUT:
-                        cdata->data_out_frame=pinfo->fd->num;
-                        break;
-                    }
+            /* first time we see this packet. check if we can find the request */
+            cdata = (iscsi_conv_data_t *)g_hash_table_lookup (iscsi_req_unmatched, &ckey);
+            if (cdata){
+                if (cdata->data_in_frame+cdata->data_out_frame+cdata->response_frame==0){
+                    /* this is the first response to the request, add it to the matched table */
+                    g_hash_table_insert (iscsi_req_matched, cdata, cdata);
                 }
-            } else {
-                iscsi_conv_data_t ckey;
-                ckey.conv_idx = conversation->index;
-                ckey.itt = tvb_get_ntohl (tvb, offset+16);
-                ckey.request_frame=0;
-                ckey.data_in_frame=0;
-                ckey.data_out_frame=0;
-                ckey.response_frame=0;
                 switch(opcode){
                 case ISCSI_OPCODE_SCSI_RESPONSE:
-                    ckey.response_frame=pinfo->fd->num;
+                    cdata->response_frame=pinfo->fd->num;
                     break;
                 case ISCSI_OPCODE_SCSI_DATA_IN:
-                    ckey.data_in_frame=pinfo->fd->num;
+                    /* a bit ugly but we need to check the S bit here */
+                    if(tvb_get_guint8(tvb, offset+1)&ISCSI_SCSI_DATA_FLAG_S){
+                        cdata->response_frame=pinfo->fd->num;
+                    }
+                    cdata->data_in_frame=pinfo->fd->num;
                     break;
                 case ISCSI_OPCODE_SCSI_DATA_OUT:
-                    ckey.data_out_frame=pinfo->fd->num;
+                    cdata->data_out_frame=pinfo->fd->num;
                     break;
                 }
-
-                /* we have seen this one before,   pick it up from the matched table */
-                cdata = (iscsi_conv_data_t *)g_hash_table_lookup (iscsi_req_matched, &ckey);
             }
-
-            if (cdata){
-                task_key.conv_id = cdata->conv_idx;
-                task_key.task_id = cdata->itt;
-                pinfo->private_data = &task_key;
-            } else {
-                pinfo->private_data = NULL;
+        } else {
+            iscsi_conv_data_t ckey;
+            ckey.conv_idx = conversation->index;
+            ckey.itt = tvb_get_ntohl (tvb, offset+16);
+            ckey.request_frame=0;
+            ckey.data_in_frame=0;
+            ckey.data_out_frame=0;
+            ckey.response_frame=0;
+            switch(opcode){
+            case ISCSI_OPCODE_SCSI_RESPONSE:
+                ckey.response_frame=pinfo->fd->num;
+                break;
+            case ISCSI_OPCODE_SCSI_DATA_IN:
+                ckey.data_in_frame=pinfo->fd->num;
+                break;
+            case ISCSI_OPCODE_SCSI_DATA_OUT:
+                ckey.data_out_frame=pinfo->fd->num;
+                break;
             }
+
+            /* we have seen this one before,   pick it up from the matched table */
+            cdata = (iscsi_conv_data_t *)g_hash_table_lookup (iscsi_req_matched, &ckey);
+        }
+
+        if (cdata){
+            task_key.conv_id = cdata->conv_idx;
+            task_key.task_id = cdata->itt;
+            pinfo->private_data = &task_key;
         } else {
-            /* no conversation, meaning we didn't see the request */
             pinfo->private_data = NULL;
         }
 
     } else if (opcode == ISCSI_OPCODE_SCSI_COMMAND) {
-        conversation = find_conversation (&pinfo->src, &pinfo->dst,
-                                          pinfo->ptype, pinfo->srcport,
-                                          pinfo->destport, 0);
-        if (!conversation) {
-            conversation = conversation_new (&pinfo->src, &pinfo->dst,
-                                             pinfo->ptype, pinfo->srcport,
-                                             pinfo->destport, 0);
-        }
-
         if (!pinfo->fd->flags.visited){
             iscsi_conv_data_t ckey;
 
@@ -1652,6 +1634,7 @@ dissect_iscsi(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gboolean chec
     guint32 available_bytes = tvb_length_remaining(tvb, offset);
     guint32 pduLen = 48;
     int digestsActive = 1;
+    conversation_t *conversation = NULL;
 
     /* quick check to see if the packet is long enough to contain the
      * minimum amount of information we need */
@@ -1759,6 +1742,17 @@ dissect_iscsi(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gboolean chec
 		pduLen += dataDigestSize;
 	}
 
+	/* make sure we have a conversation for this session */
+        conversation = find_conversation (&pinfo->src, &pinfo->dst,
+                                          pinfo->ptype, pinfo->srcport,
+                                          pinfo->destport, 0);
+        if (!conversation) {
+            conversation = conversation_new (&pinfo->src, &pinfo->dst,
+                                             pinfo->ptype, pinfo->srcport,
+                                             pinfo->destport, 0);
+        }
+/*qqq  header digest autodetection should go in here */
+
 	/*
 	 * Desegmentation check.
 	 */
@@ -1800,7 +1794,7 @@ dissect_iscsi(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gboolean chec
 		col_append_str(pinfo->cinfo, COL_INFO, ", ");
 	}
 
-	dissect_iscsi_pdu(tvb, pinfo, tree, offset, opcode, opcode_str, data_segment_len);
+	dissect_iscsi_pdu(tvb, pinfo, tree, offset, opcode, opcode_str, data_segment_len, conversation);
 	if(pduLen > available_bytes)
 	    pduLen = available_bytes;
 	offset += pduLen;