Fix is_ssh_blocked and is_http_blocked

This patch fixes JIRA SFC-79

Previously, those functions used regex matching against the command output.
Now, the return code from netcat is used. It should be easier and more
relieable.

Change-Id: I639c64b3fe0a0e3c0b59f73e5615b8737e676849
Signed-off-by: Juan Vidal <juan.vidal.allende@ericsson.com>

1 files changed, 17 insertions, 21 deletions

diff --git a/sfc/lib/utils.py b/sfc/lib/utils.py
index 8bd67e4f..5ca53077 100644
--- a/sfc/lib/utils.py
+++ b/sfc/lib/utils.py
@@ -238,32 +238,28 @@ def vxlan_tool_stop(sf):
     run_cmd_remote(sf, cmd)
 
 
-def netcat(s_ip, c_ip, port="80", timeout=5):
-    """Run netcat on a give machine, Can be VM"""
-    cmd = "nc -zv "
-    cmd = cmd + " -w %s %s %s" % (timeout, s_ip, port)
-    cmd = cmd + " 2>&1"
-    _, output, _ = run_cmd_remote(c_ip, cmd)
+def netcat(source_ip, destination_ip, port, timeout=5):
+    """
+    SSH into source_ip, and check the connectivity from there to destination_ip
+    on the specified port, using the netcat command.
+    Returns 0 on successful execution, != 0 on failure
+    """
+    cmd = "nc -zv -w %s %s %s 2>&1" % (timeout, destination_ip, port)
+    rc, output, _ = run_cmd_remote(source_ip, cmd)
+    logger.info("Running netcat from [%s] - connecting to [%s] on port [%s]" %
+                (source_ip, destination_ip, port))
     logger.info("%s" % output)
-    return output
+    return rc
 
 
-def is_ssh_blocked(srv_prv_ip, client_ip):
-    res = netcat(srv_prv_ip, client_ip, port="22")
-    match = re.search("nc:.*timed out:.*", res, re.M)
-    if match:
-        return True
-
-    return False
+def is_ssh_blocked(source_ip, destination_ip):
+    rc = netcat(source_ip, destination_ip, port="22")
+    return rc != 0
 
 
-def is_http_blocked(srv_prv_ip, client_ip):
-    res = netcat(srv_prv_ip, client_ip, port="80")
-    match = re.search(".* 80 port.* succeeded!", res, re.M)
-    if match:
-        return False
-
-    return True
+def is_http_blocked(source_ip, destination_ip):
+    rc = netcat(source_ip, destination_ip, port="80")
+    return rc != 0
 
 
 def capture_ovs_logs(ovs_logger, controller_clients, compute_clients, error):