osmo-sgsn/contrib/a-link/sccp-split-by-con.lua

171 lines
4.4 KiB
Lua

-- Split trace based on SCCP Source
-- There are still bugs to find... bugs bugs bugs... hmm
do
local function init_listener()
print("CREATED LISTENER")
local tap = Listener.new("ip", "sccp && (ip.src == 172.16.1.81 || ip.dst == 172.16.1.81)")
local sccp_type_field = Field.new("sccp.message_type")
local sccp_src_field = Field.new("sccp.slr")
local sccp_dst_field = Field.new("sccp.dlr")
local msg_type_field = Field.new("gsm_a.dtap_msg_mm_type")
local lu_rej_field = Field.new("gsm_a.dtap.rej_cause")
local ip_src_field = Field.new("ip.src")
local ip_dst_field = Field.new("ip.dst")
--
local bssmap_msgtype_field = Field.new("gsm_a.bssmap_msgtype")
-- assignment failure 0x03
--
--
local dtap_cause_field = Field.new("gsm_a_dtap.cause")
local dtap_cc_field = Field.new("gsm_a.dtap_msg_cc_type")
local connections = {}
function check_failure(con)
check_lu_reject(con)
check_disconnect(con)
check_failures(con)
end
-- cipher mode reject
function check_failures(con)
local msgtype = bssmap_msgtype_field()
if not msgtype then
return
end
msgtype = tonumber(msgtype)
if msgtype == 89 then
print("Cipher mode reject")
con[4] = true
elseif msgtype == 0x03 then
print("Assignment failure")
con[4] = true
elseif msgtype == 0x22 then
print("Clear Request... RF failure?")
con[4] = true
end
end
-- check if a DISCONNECT is normal
function check_disconnect(con)
local msg_type = dtap_cc_field()
if not msg_type then
return
end
if tonumber(msg_type) ~= 0x25 then
return
end
local cause = dtap_cause_field()
if not cause then
return
end
cause = tonumber(cause)
if cause ~= 0x10 then
print("DISCONNECT != Normal")
con[4] = true
end
end
-- check if we have a LU Reject
function check_lu_reject(con)
local msg_type = msg_type_field()
if not msg_type then
return
end
msg_type = tonumber(tostring(msg_type))
if msg_type == 0x04 then
print("LU REJECT with " .. tostring(lu_rej_field()))
con[4] = true
end
end
function tap.packet(pinfo,tvb,ip)
local ip_src = tostring(ip_src_field())
local ip_dst = tostring(ip_dst_field())
local sccp_type = tonumber(tostring(sccp_type_field()))
local sccp_src = sccp_src_field()
local sccp_dst = sccp_dst_field()
local con
if sccp_type == 0x01 then
elseif sccp_type == 0x2 then
local src = string.format("%s-%s", ip_src, tostring(sccp_src))
local dst = string.format("%s-%s", ip_dst, tostring(sccp_dst))
local datestring = os.date("%Y%m%d%H%M%S")
local pcap_name = string.format("alink_trace_%s-%s_%s.pcap", src, dst, datestring)
local dumper = Dumper.new_for_current(pcap_name)
local con = { ip_src, tostring(sccp_src), tostring(sccp_dst), false, dumper, pcap_name }
dumper:dump_current()
connections[src] = con
connections[dst] = con
elseif sccp_type == 0x4 then
-- close a connection... remove it from the list
local src = string.format("%s-%s", ip_src, tostring(sccp_src))
local dst = string.format("%s-%s", ip_dst, tostring(sccp_dst))
local con = connections[src]
if not con then
return
end
con[5]:dump_current()
con[5]:flush()
-- this causes a crash on unpacted wireshark
con[5]:close()
-- the connection had a failure
if con[4] == true then
local datestring = os.date("%Y%m%d%H%M%S")
local new_name = string.format("alink_failure_%s_%s-%s.pcap", datestring, con[2], con[3])
os.rename(con[6], new_name)
else
os.remove(con[6])
end
-- clear the old connection
connections[src] = nil
connections[dst] = nil
elseif sccp_type == 0x5 then
-- not handled yet... we should verify stuff here...
local dst = string.format("%s-%s", ip_dst, tostring(sccp_dst))
local con = connections[dst]
if not con then
return
end
con[5]:dump_current()
elseif sccp_type == 0x6 then
local dst = string.format("%s-%s", ip_dst, tostring(sccp_dst))
local con = connections[dst]
if not con then
print("DON'T KNOW THIS CONNECTION for " .. ip_dst)
return
end
con[5]:dump_current()
check_failure(con)
end
end
function tap.draw()
print("DRAW")
end
function tap.reset()
print("RESET")
end
end
init_listener()
end