#!/usr/bin/expect
#
# Pedit Main Test 5
#
# Purpose:  
# To test the pedit/munge/set capabilities.
#
# What it does:
# -Run tcpdump beforehand, and capture a hex dump of a packet.
# -Install a rule stating that any packet that arrives on loopback
# (ingress) and is destined for 127.0.0.1 will be edited.  Offset 0
# will be rewritten to 0x12345678
# -Run tcpdump afterwards, and check the differences between packets
#
# Expected result:
# -The ping will fail, and offset 0 of the packet will contain 0x12345678
#


# Set description for use with libtest
set libtest_description "Pedit action: setting a u32 range at offset 0."
 
# Source common test procedures and run set-up commands
source ./libtest.tcl

# Delete any ingress qdiscs associated with loopback in order to clear state
send "tc qdisc del dev lo ingress\r"

# Send initial pings to establish a base case
send "sleep 1;  ping 127.0.0.1 -c 3 &\r "

# Get a tcpdump hex output for a packet
send "tcpdump -i lo -s 96 -vvv -x host 127.0.0.1 and icmp\[icmptype\]=icmp-echo -c 1\r"
if [expect_tcpdump_results before_list] {
	output_test_failure "Error while expecting tcpdump results"
	return -1
} 

# Add an ingress qdisc
send "tc qdisc add dev lo ingress\r"
 
# Match IP destination 127.0.0.1, and edit these packets to set the 4 octets
# at offset 0 to be 0x12345678
send "tc filter add dev lo parent ffff: protocol ip prio 10 u32 match ip dst 127.0.0.1/32 flowid 1:1 action pedit munge offset 0 u32 set 0x12345678 pipe action mirred egress redirect dev dummy0\r"

# Send a few pings to 127.0.0.1 while tcpdump is running on dummy0 and capture
# the data.
expect -re ".*"
send "sleep 1;  ping 127.0.0.1 -c 2 &\r"

# Get a tcpdump hex output for a packet
send "tcpdump -i dummy0 -s 96 -vvv -x -c 1\r"
if [expect_tcpdump_results after_list] {
        output_test_failure "Error while expecting tcpdump results"
        return -1
} 

# Extra logging
output_test_message "Before: $before_list"
output_test_message "After:  $after_list"

# Check the results.  In this case, data at offsets 0-3 was changed.

# Offsets 0-1 should be 0x1234
if {[lindex $before_list 0] == [lindex $after_list 0]} {
	output_test_failure "Test failed at offsets 0-1"
	return -1
} else {
	if {[lindex $after_list 0] != "1234"} {
		output_test_failure "Test failed at offsets 0-1."
		return -1
	} else {
		output_test_message "Offsets 0-1 changed to 0x1234 (success)"
	}
}

# Offsets 2-3 should be 0x5678
if {[lindex $before_list 1] == [lindex $after_list 1]} {
	output_test_failure "Test failed at offsets 2-3"
	return -1
} else {
	if {[lindex $after_list 1] != "5678"} {
		output_test_failure "Test failed at offsets 2-3"
		return -1
	} else {
		output_test_message "Offsets 2-3 changed to 0x5678 (success)"
	}
}

# Ensure that all expected matching portions of the packet are identical
set exemptions [concat $DEFAULT_TCPDUMP_ICMP_EXEMPTION 0 1]
if [compare_lists $before_list $after_list $exemptions $DEFAULT_TCPDUMP_LENGTH mismatch_index] {
	output_test_failure "Test failed at $mismatch_index"
	return -1
} 

expect -re ".*"
output_test_success
return 0