Broken run

[adrianosela]

01:18 $ sudo go run main.go -h 151.156.31.34 -p 80
# command-line-arguments
./main.go:92:8: undefined: ipv4Header
./main.go:100:2: not enough arguments to return
./main.go:134:8: undefined: tcpHeader
./main.go:170:2: not enough arguments to return