DNS package with bad CNAME

gistfile1.rkt

(;; random ID
 0 187
 ;; QR Opcode  AA TC RD RA Z     RCODE
 ;; 1  0 0 0 0 0  0  1  1  0 0 0 0 0 0 0
 129 128
 ;; QDCOUNT
 0 1
 ;; ANSCOUNT
 0 1
 ;; NSCOUNT
 0 1
 ;; ARCOUNT
 0 0
 ;; QNAME (stat.ethz.ch)
 4 115 116 97 116
 4 101 116 104 122
 2 99 104 0
 ;; QTYPE (MX)
 0 15
 ;; QCLASS (IN)
 0 1
 ;; NAME (pointer)
 ;; 1100000000001100
 192 12
 ;; TYPE: CNAME
 0 5
 ;; CLASS
 0 1
 ;; TTL
 0 0
 4 79
 ;; RDLENGTH
 0 19
 ;; RDATA
 11 109 97 103 101 108 108 97 110 45 48 54
 4 109 97 116 104
 192 17
 ;; NAME (pointer)
 192 17
 ;; TYPE: SOA
 0 6
 ;; CLASS
 0 1
 ;; TTL
 0 0 1 90
 ;; RDLENGTH & DATA
 0 44 8 100 117 109 109 121 45
 110 115 192 17 10 104 111 115 116 109
 97 115 116 101 114 192 17 119 168 176
 33 0 0 42 48 0 0 14 16 0 27 175 128 0 0 2 88)